X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/39236c6e673c41db228275375ab7fdb0f837b292..cb3231590a3c94ab4375e2228bd5e86b0cf1ad7e:/bsd/netinet/tcp_input.c diff --git a/bsd/netinet/tcp_input.c b/bsd/netinet/tcp_input.c index 005d449c2..d7d04516a 100644 --- a/bsd/netinet/tcp_input.c +++ b/bsd/netinet/tcp_input.c @@ -1,8 +1,8 @@ /* - * Copyright (c) 2000-2013 Apple Inc. All rights reserved. + * Copyright (c) 2000-2019 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ - * + * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in @@ -11,10 +11,10 @@ * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. - * + * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. - * + * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, @@ -22,7 +22,7 @@ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. - * + * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /* @@ -73,14 +73,17 @@ #include #include #include -#include /* for proc0 declaration */ +#include /* for proc0 declaration */ #include #include #include #include #include +#if !CONFIG_EMBEDDED #include -#include /* before tcp_seq.h, for tcp_random18() */ +#endif +#include +#include /* before tcp_seq.h, for tcp_random18() */ #include @@ -88,14 +91,16 @@ #include #include #include +#include #include +#include #include #include #include -#include /* for ICMP_BANDLIM */ +#include /* for ICMP_BANDLIM */ #include -#include /* for ICMP_BANDLIM */ +#include /* for ICMP_BANDLIM */ #include #include #include @@ -107,6 +112,7 @@ #include #endif #include +#include #include #include #include @@ -123,6 +129,7 @@ u_char tcp_saveipgen[40]; /* the size must be of max ip header, now IPv6 */ struct tcphdr tcp_savetcp; #endif /* TCPDEBUG */ +#include #if IPSEC #include @@ -141,185 +148,178 @@ struct tcphdr tcp_savetcp; #if MPTCP #include #include -#include +#include #endif /* MPTCP */ -#define DBG_LAYER_BEG NETDBG_CODE(DBG_NETTCP, 0) -#define DBG_LAYER_END NETDBG_CODE(DBG_NETTCP, 2) +#include + +#define DBG_LAYER_BEG NETDBG_CODE(DBG_NETTCP, 0) +#define DBG_LAYER_END NETDBG_CODE(DBG_NETTCP, 2) #define DBG_FNC_TCP_INPUT NETDBG_CODE(DBG_NETTCP, (3 << 8)) #define DBG_FNC_TCP_NEWCONN NETDBG_CODE(DBG_NETTCP, (7 << 8)) -tcp_cc tcp_ccgen; - -#if IPSEC -extern int ipsec_bypass; -#endif - -extern int32_t total_sbmb_cnt; +#define TCP_RTT_HISTORY_EXPIRE_TIME (60 * TCP_RETRANSHZ) +#define TCP_RECV_THROTTLE_WIN (5 * TCP_RETRANSHZ) +#define TCP_STRETCHACK_ENABLE_PKTCNT 2000 -struct tcpstat tcpstat; +struct tcpstat tcpstat; static int log_in_vain = 0; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_in_vain, CTLFLAG_RW | CTLFLAG_LOCKED, - &log_in_vain, 0, "Log all incoming TCP connections"); +SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_in_vain, + CTLFLAG_RW | CTLFLAG_LOCKED, &log_in_vain, 0, + "Log all incoming TCP connections"); static int blackhole = 0; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, blackhole, CTLFLAG_RW | CTLFLAG_LOCKED, - &blackhole, 0, "Do not send RST when dropping refused connections"); +SYSCTL_INT(_net_inet_tcp, OID_AUTO, blackhole, + CTLFLAG_RW | CTLFLAG_LOCKED, &blackhole, 0, + "Do not send RST when dropping refused connections"); -int tcp_delack_enabled = 3; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, delayed_ack, CTLFLAG_RW | CTLFLAG_LOCKED, - &tcp_delack_enabled, 0, +SYSCTL_SKMEM_TCP_INT(OID_AUTO, delayed_ack, + CTLFLAG_RW | CTLFLAG_LOCKED, int, tcp_delack_enabled, 3, "Delay ACK to try and piggyback it onto a data packet"); -int tcp_lq_overflow = 1; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcp_lq_overflow, CTLFLAG_RW | CTLFLAG_LOCKED, - &tcp_lq_overflow, 0, +SYSCTL_SKMEM_TCP_INT(OID_AUTO, tcp_lq_overflow, + CTLFLAG_RW | CTLFLAG_LOCKED, int, tcp_lq_overflow, 1, "Listen Queue Overflow"); -int tcp_recv_bg = 0; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, recvbg, CTLFLAG_RW | CTLFLAG_LOCKED, - &tcp_recv_bg, 0, - "Receive background"); +SYSCTL_SKMEM_TCP_INT(OID_AUTO, recvbg, CTLFLAG_RW | CTLFLAG_LOCKED, + int, tcp_recv_bg, 0, "Receive background"); #if TCP_DROP_SYNFIN -static int drop_synfin = 1; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, drop_synfin, CTLFLAG_RW | CTLFLAG_LOCKED, - &drop_synfin, 0, "Drop TCP packets with SYN+FIN set"); +SYSCTL_SKMEM_TCP_INT(OID_AUTO, drop_synfin, + CTLFLAG_RW | CTLFLAG_LOCKED, static int, drop_synfin, 1, + "Drop TCP packets with SYN+FIN set"); #endif -SYSCTL_NODE(_net_inet_tcp, OID_AUTO, reass, CTLFLAG_RW|CTLFLAG_LOCKED, 0, +SYSCTL_NODE(_net_inet_tcp, OID_AUTO, reass, CTLFLAG_RW | CTLFLAG_LOCKED, 0, "TCP Segment Reassembly Queue"); -__private_extern__ int tcp_reass_maxseg = 0; -SYSCTL_INT(_net_inet_tcp_reass, OID_AUTO, maxsegments, CTLFLAG_RW | CTLFLAG_LOCKED, - &tcp_reass_maxseg, 0, - "Global maximum number of TCP Segments in Reassembly Queue"); - -__private_extern__ int tcp_reass_qsize = 0; -SYSCTL_INT(_net_inet_tcp_reass, OID_AUTO, cursegments, CTLFLAG_RD | CTLFLAG_LOCKED, - &tcp_reass_qsize, 0, - "Global number of TCP Segments currently in Reassembly Queue"); - static int tcp_reass_overflows = 0; -SYSCTL_INT(_net_inet_tcp_reass, OID_AUTO, overflows, CTLFLAG_RD | CTLFLAG_LOCKED, - &tcp_reass_overflows, 0, +SYSCTL_INT(_net_inet_tcp_reass, OID_AUTO, overflows, + CTLFLAG_RD | CTLFLAG_LOCKED, &tcp_reass_overflows, 0, "Global number of TCP Segment Reassembly Queue Overflows"); -__private_extern__ int slowlink_wsize = 8192; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, slowlink_wsize, CTLFLAG_RW | CTLFLAG_LOCKED, - &slowlink_wsize, 0, "Maximum advertised window size for slowlink"); +SYSCTL_SKMEM_TCP_INT(OID_AUTO, slowlink_wsize, CTLFLAG_RW | CTLFLAG_LOCKED, + __private_extern__ int, slowlink_wsize, 8192, + "Maximum advertised window size for slowlink"); -int maxseg_unacked = 8; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, maxseg_unacked, CTLFLAG_RW | CTLFLAG_LOCKED, - &maxseg_unacked, 0, "Maximum number of outstanding segments left unacked"); +SYSCTL_SKMEM_TCP_INT(OID_AUTO, maxseg_unacked, + CTLFLAG_RW | CTLFLAG_LOCKED, int, maxseg_unacked, 8, + "Maximum number of outstanding segments left unacked"); -int tcp_do_rfc3465 = 1; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, rfc3465, CTLFLAG_RW | CTLFLAG_LOCKED, - &tcp_do_rfc3465, 0, ""); +SYSCTL_SKMEM_TCP_INT(OID_AUTO, rfc3465, CTLFLAG_RW | CTLFLAG_LOCKED, + int, tcp_do_rfc3465, 1, ""); -int tcp_do_rfc3465_lim2 = 1; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, rfc3465_lim2, CTLFLAG_RW | CTLFLAG_LOCKED, - &tcp_do_rfc3465_lim2, 0, "Appropriate bytes counting w/ L=2*SMSS"); +SYSCTL_SKMEM_TCP_INT(OID_AUTO, rfc3465_lim2, + CTLFLAG_RW | CTLFLAG_LOCKED, int, tcp_do_rfc3465_lim2, 1, + "Appropriate bytes counting w/ L=2*SMSS"); -int rtt_samples_per_slot = 20; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, rtt_samples_per_slot, CTLFLAG_RW | CTLFLAG_LOCKED, - &rtt_samples_per_slot, 0, "Number of RTT samples stored for rtt history"); - -int tcp_allowed_iaj = ALLOWED_IAJ; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, recv_allowed_iaj, CTLFLAG_RW | CTLFLAG_LOCKED, - &tcp_allowed_iaj, 0, "Allowed inter-packet arrival jiter"); - -int tcp_acc_iaj_high_thresh = ACC_IAJ_HIGH_THRESH; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, acc_iaj_high_thresh, CTLFLAG_RW | CTLFLAG_LOCKED, - &tcp_acc_iaj_high_thresh, 0, "Used in calculating maximum accumulated IAJ"); - -u_int32_t tcp_do_autorcvbuf = 1; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, doautorcvbuf, CTLFLAG_RW | CTLFLAG_LOCKED, - &tcp_do_autorcvbuf, 0, "Enable automatic socket buffer tuning"); +int rtt_samples_per_slot = 20; +int tcp_acc_iaj_high_thresh = ACC_IAJ_HIGH_THRESH; u_int32_t tcp_autorcvbuf_inc_shift = 3; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, autorcvbufincshift, CTLFLAG_RW | CTLFLAG_LOCKED, - &tcp_autorcvbuf_inc_shift, 0, "Shift for increment in receive socket buffer size"); - -u_int32_t tcp_autorcvbuf_max = 512 * 1024; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, autorcvbufmax, CTLFLAG_RW | CTLFLAG_LOCKED, - &tcp_autorcvbuf_max, 0, "Maximum receive socket buffer size"); - +SYSCTL_SKMEM_TCP_INT(OID_AUTO, recv_allowed_iaj, + CTLFLAG_RW | CTLFLAG_LOCKED, int, tcp_allowed_iaj, ALLOWED_IAJ, + "Allowed inter-packet arrival jiter"); +#if (DEVELOPMENT || DEBUG) +SYSCTL_INT(_net_inet_tcp, OID_AUTO, acc_iaj_high_thresh, + CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_acc_iaj_high_thresh, 0, + "Used in calculating maximum accumulated IAJ"); + +SYSCTL_INT(_net_inet_tcp, OID_AUTO, autorcvbufincshift, + CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_autorcvbuf_inc_shift, 0, + "Shift for increment in receive socket buffer size"); +#endif /* (DEVELOPMENT || DEBUG) */ + +SYSCTL_SKMEM_TCP_INT(OID_AUTO, doautorcvbuf, + CTLFLAG_RW | CTLFLAG_LOCKED, u_int32_t, tcp_do_autorcvbuf, 1, + "Enable automatic socket buffer tuning"); + +SYSCTL_SKMEM_TCP_INT(OID_AUTO, autorcvbufmax, + CTLFLAG_RW | CTLFLAG_LOCKED, u_int32_t, tcp_autorcvbuf_max, 512 * 1024, + "Maximum receive socket buffer size"); + +#if CONFIG_EMBEDDED +int sw_lro = 1; +#else int sw_lro = 0; +#endif /* !CONFIG_EMBEDDED */ SYSCTL_INT(_net_inet_tcp, OID_AUTO, lro, CTLFLAG_RW | CTLFLAG_LOCKED, - &sw_lro, 0, "Used to coalesce TCP packets"); + &sw_lro, 0, "Used to coalesce TCP packets"); int lrodebug = 0; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, lrodbg, CTLFLAG_RW | CTLFLAG_LOCKED, - &lrodebug, 0, "Used to debug SW LRO"); +SYSCTL_INT(_net_inet_tcp, OID_AUTO, lrodbg, + CTLFLAG_RW | CTLFLAG_LOCKED, &lrodebug, 0, + "Used to debug SW LRO"); int lro_start = 4; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, lro_startcnt, CTLFLAG_RW | CTLFLAG_LOCKED, - &lro_start, 0, "Segments for starting LRO computed as power of 2"); - -extern int tcp_do_autosendbuf; +SYSCTL_INT(_net_inet_tcp, OID_AUTO, lro_startcnt, + CTLFLAG_RW | CTLFLAG_LOCKED, &lro_start, 0, + "Segments for starting LRO computed as power of 2"); int limited_txmt = 1; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, limited_transmit, CTLFLAG_RW | CTLFLAG_LOCKED, - &limited_txmt, 0, "Enable limited transmit"); - int early_rexmt = 1; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, early_rexmt, CTLFLAG_RW | CTLFLAG_LOCKED, - &early_rexmt, 0, "Enable Early Retransmit"); - int sack_ackadv = 1; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, sack_ackadv, CTLFLAG_RW | CTLFLAG_LOCKED, - &sack_ackadv, 0, "Use SACK with cumulative ack advancement as a dupack"); +int tcp_dsack_enable = 1; -#if CONFIG_IFEF_NOWINDOWSCALE -int tcp_obey_ifef_nowindowscale = 0; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, obey_ifef_nowindowscale, CTLFLAG_RW | CTLFLAG_LOCKED, - &tcp_obey_ifef_nowindowscale, 0, ""); -#endif +#if (DEVELOPMENT || DEBUG) +SYSCTL_INT(_net_inet_tcp, OID_AUTO, limited_transmit, + CTLFLAG_RW | CTLFLAG_LOCKED, &limited_txmt, 0, + "Enable limited transmit"); -/* This limit will determine when the receive socket buffer tuning will - * kick in. Currently it will start when the bw*delay measured in - * last RTT is more than half of the current hiwat on the buffer. - */ -uint32_t tcp_rbuf_hiwat_shift = 1; +SYSCTL_INT(_net_inet_tcp, OID_AUTO, early_rexmt, + CTLFLAG_RW | CTLFLAG_LOCKED, &early_rexmt, 0, + "Enable Early Retransmit"); -/* This limit will determine when the socket buffer will be increased - * to accommodate an application reading slowly. When the amount of - * space left in the buffer is less than one forth of the bw*delay - * measured in last RTT. - */ -uint32_t tcp_rbuf_win_shift = 2; +SYSCTL_INT(_net_inet_tcp, OID_AUTO, sack_ackadv, + CTLFLAG_RW | CTLFLAG_LOCKED, &sack_ackadv, 0, + "Use SACK with cumulative ack advancement as a dupack"); + +SYSCTL_INT(_net_inet_tcp, OID_AUTO, dsack_enable, + CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_dsack_enable, 0, + "use DSACK TCP option to report duplicate segments"); + +#endif /* (DEVELOPMENT || DEBUG) */ +int tcp_disable_access_to_stats = 1; +SYSCTL_INT(_net_inet_tcp, OID_AUTO, disable_access_to_stats, + CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_disable_access_to_stats, 0, + "Disable access to tcpstat"); + +SYSCTL_SKMEM_TCP_INT(OID_AUTO, challengeack_limit, + CTLFLAG_RW | CTLFLAG_LOCKED, uint32_t, tcp_challengeack_limit, 10, + "Maximum number of challenge ACKs per connection per second"); + +SYSCTL_SKMEM_TCP_INT(OID_AUTO, do_rfc5961, + CTLFLAG_RW | CTLFLAG_LOCKED, static int, tcp_do_rfc5961, 1, + "Enable/Disable full RFC 5961 compliance"); -extern int tcp_TCPTV_MIN; extern int tcp_acc_iaj_high; extern int tcp_acc_iaj_react_limit; -extern struct zone *tcp_reass_zone; int tcprexmtthresh = 3; u_int32_t tcp_now; -struct timeval tcp_uptime; /* uptime when tcp_now was last updated */ -lck_spin_t *tcp_uptime_lock; /* Used to sychronize updates to tcp_now */ +struct timeval tcp_uptime; /* uptime when tcp_now was last updated */ +lck_spin_t *tcp_uptime_lock; /* Used to sychronize updates to tcp_now */ struct inpcbhead tcb; -#define tcb6 tcb /* for KAME src sync over BSD*'s */ +#define tcb6 tcb /* for KAME src sync over BSD*'s */ struct inpcbinfo tcbinfo; static void tcp_dooptions(struct tcpcb *, u_char *, int, struct tcphdr *, - struct tcpopt *, unsigned int); -static void tcp_pulloutofband(struct socket *, - struct tcphdr *, struct mbuf *, int); -static int tcp_reass(struct tcpcb *, struct tcphdr *, int *, struct mbuf *, - struct ifnet *); -static void tcp_xmit_timer(struct tcpcb *, int, u_int32_t, tcp_seq); + struct tcpopt *); +static void tcp_finalize_options(struct tcpcb *, struct tcpopt *, unsigned int); +static void tcp_pulloutofband(struct socket *, + struct tcphdr *, struct mbuf *, int); +static void tcp_xmit_timer(struct tcpcb *, int, u_int32_t, tcp_seq); static inline unsigned int tcp_maxmtu(struct rtentry *); -static inline int tcp_stretch_ack_enable(struct tcpcb *tp); +static inline int tcp_stretch_ack_enable(struct tcpcb *tp, int thflags); static inline void tcp_adaptive_rwtimo_check(struct tcpcb *, int); #if TRAFFIC_MGT -static inline void update_iaj_state(struct tcpcb *tp, uint32_t tlen, int reset_size); +static inline void update_iaj_state(struct tcpcb *tp, uint32_t tlen, + int reset_size); void compute_iaj(struct tcpcb *tp, int nlropkts, int lro_delay_factor); static void compute_iaj_meat(struct tcpcb *tp, uint32_t cur_iaj); #endif /* TRAFFIC_MGT */ @@ -328,49 +328,48 @@ static void compute_iaj_meat(struct tcpcb *tp, uint32_t cur_iaj); static inline unsigned int tcp_maxmtu6(struct rtentry *); #endif -static void tcp_sbrcv_grow(struct tcpcb *tp, struct sockbuf *sb, - struct tcpopt *to, u_int32_t tlen); +unsigned int get_maxmtu(struct rtentry *); +static void tcp_sbrcv_grow(struct tcpcb *tp, struct sockbuf *sb, + struct tcpopt *to, u_int32_t tlen, u_int32_t rcvbuf_max); void tcp_sbrcv_trim(struct tcpcb *tp, struct sockbuf *sb); static void tcp_sbsnd_trim(struct sockbuf *sbsnd); static inline void tcp_sbrcv_tstmp_check(struct tcpcb *tp); static inline void tcp_sbrcv_reserve(struct tcpcb *tp, struct sockbuf *sb, - u_int32_t newsize, u_int32_t idealsize); + u_int32_t newsize, u_int32_t idealsize, u_int32_t rcvbuf_max); static void tcp_bad_rexmt_restore_state(struct tcpcb *tp, struct tcphdr *th); -static int tcp_detect_bad_rexmt(struct tcpcb *tp, struct tcpopt *to); -static void tcp_compute_rtt(struct tcpcb *tp, struct tcpopt *to, - struct tcphdr *th); - +static void tcp_compute_rtt(struct tcpcb *tp, struct tcpopt *to, + struct tcphdr *th); +static void tcp_early_rexmt_check(struct tcpcb *tp, struct tcphdr *th); +static void tcp_bad_rexmt_check(struct tcpcb *tp, struct tcphdr *th, + struct tcpopt *to); /* - * Constants used for resizing receive socket buffer - * when timestamps are not supported + * Constants used for resizing receive socket buffer + * when timestamps are not supported */ #define TCPTV_RCVNOTS_QUANTUM 100 #define TCP_RCVNOTS_BYTELEVEL 204800 -/* - * Constants used for limiting early retransmits +/* + * Constants used for limiting early retransmits * to 10 per minute. */ #define TCP_EARLY_REXMT_WIN (60 * TCP_RETRANSHZ) /* 60 seconds */ #define TCP_EARLY_REXMT_LIMIT 10 -extern void add_to_time_wait(struct tcpcb *, uint32_t delay); -extern void postevent(struct socket *, struct sockbuf *, int); - -extern void ipfwsyslog( int level, const char *format,...); +extern void ipfwsyslog( int level, const char *format, ...); extern int fw_verbose; #if IPFIREWALL extern void ipfw_stealth_stats_incr_tcp(void); #define log_in_vain_log( a ) { \ - if ( (log_in_vain == 3 ) && (fw_verbose == 2)) { /* Apple logging, log to ipfw.log */ \ - ipfwsyslog a ; \ - } else if ( (log_in_vain == 4 ) && (fw_verbose == 2)) { \ - ipfw_stealth_stats_incr_tcp(); \ - } \ - else log a ; \ + if ( (log_in_vain == 3 ) && (fw_verbose == 2)) { /* Apple logging, log to ipfw.log */ \ + ipfwsyslog a ; \ + } else if ( (log_in_vain == 4 ) && (fw_verbose == 2)) { \ + ipfw_stealth_stats_incr_tcp(); \ + } \ + else log a ; \ } #else #define log_in_vain_log( a ) { log a; } @@ -378,18 +377,15 @@ extern void ipfw_stealth_stats_incr_tcp(void); int tcp_rcvunackwin = TCPTV_UNACKWIN; int tcp_maxrcvidle = TCPTV_MAXRCVIDLE; -int tcp_rcvsspktcnt = TCP_RCV_SS_PKTCOUNT; -SYSCTL_INT(_net_inet_tcp, OID_AUTO, rcvsspktcnt, CTLFLAG_RW | CTLFLAG_LOCKED, - &tcp_rcvsspktcnt, 0, "packets to be seen before receiver stretches acks"); +SYSCTL_SKMEM_TCP_INT(OID_AUTO, rcvsspktcnt, CTLFLAG_RW | CTLFLAG_LOCKED, + int, tcp_rcvsspktcnt, TCP_RCV_SS_PKTCOUNT, "packets to be seen before receiver stretches acks"); #define DELAY_ACK(tp, th) \ (CC_ALGO(tp)->delay_ack != NULL && CC_ALGO(tp)->delay_ack(tp, th)) static int tcp_dropdropablreq(struct socket *head); static void tcp_newreno_partial_ack(struct tcpcb *tp, struct tcphdr *th); - static void update_base_rtt(struct tcpcb *tp, uint32_t rtt); -uint32_t get_base_rtt(struct tcpcb *tp); void tcp_set_background_cc(struct socket *so); void tcp_set_foreground_cc(struct socket *so); static void tcp_set_new_cc(struct socket *so, uint16_t cc_index); @@ -400,15 +396,15 @@ void reset_acc_iaj(struct tcpcb *tp) { tp->acc_iaj = 0; - tp->iaj_rwintop = 0; CLEAR_IAJ_STATE(tp); } static inline void update_iaj_state(struct tcpcb *tp, uint32_t size, int rst_size) { - if (rst_size > 0) + if (rst_size > 0) { tp->iaj_size = 0; + } if (tp->iaj_size == 0 || size >= tp->iaj_size) { tp->iaj_size = size; tp->iaj_rcv_ts = tcp_now; @@ -416,15 +412,16 @@ update_iaj_state(struct tcpcb *tp, uint32_t size, int rst_size) } } -/* For every 32 bit unsigned integer(v), this function will find the - * largest integer n such that (n*n <= v). This takes at most 16 iterations - * irrespective of the value of v and does not involve multiplications. +/* For every 32 bit unsigned integer(v), this function will find the + * largest integer n such that (n*n <= v). This takes at most 16 iterations + * irrespective of the value of v and does not involve multiplications. */ static inline int -isqrt(unsigned int val) { +isqrt(unsigned int val) +{ unsigned int sqrt_cache[11] = {0, 1, 4, 9, 16, 25, 36, 49, 64, 81, 100}; - unsigned int temp, g=0, b=0x8000, bshft=15; - if ( val <= 100) { + unsigned int temp, g = 0, b = 0x8000, bshft = 15; + if (val <= 100) { for (g = 0; g <= 10; ++g) { if (sqrt_cache[g] > val) { g--; @@ -441,20 +438,20 @@ isqrt(unsigned int val) { val -= temp; } b >>= 1; - } while ( b > 0 && val > 0); - } - return(g); -} - -/* -* With LRO, roughly estimate the inter arrival time between -* each sub coalesced packet as an average. Count the delay -* cur_iaj to be the delay between the last packet received -* and the first packet of the LRO stream. Due to round off errors -* cur_iaj may be the same as lro_delay_factor. Averaging has -* round off errors too. lro_delay_factor may be close to 0 -* in steady state leading to lower values fed to compute_iaj_meat. -*/ + } while (b > 0 && val > 0); + } + return g; +} + +/* + * With LRO, roughly estimate the inter arrival time between + * each sub coalesced packet as an average. Count the delay + * cur_iaj to be the delay between the last packet received + * and the first packet of the LRO stream. Due to round off errors + * cur_iaj may be the same as lro_delay_factor. Averaging has + * round off errors too. lro_delay_factor may be close to 0 + * in steady state leading to lower values fed to compute_iaj_meat. + */ void compute_iaj(struct tcpcb *tp, int nlropkts, int lro_delay_factor) { @@ -466,25 +463,26 @@ compute_iaj(struct tcpcb *tp, int nlropkts, int lro_delay_factor) } compute_iaj_meat(tp, cur_iaj); - - if (nlropkts <= 1) + + if (nlropkts <= 1) { return; + } nlropkts--; - - timediff = lro_delay_factor/nlropkts; - while (nlropkts > 0) - { - compute_iaj_meat(tp, timediff); + timediff = lro_delay_factor / nlropkts; + + while (nlropkts > 0) { + compute_iaj_meat(tp, timediff); nlropkts--; } } static -void compute_iaj_meat(struct tcpcb *tp, uint32_t cur_iaj) +void +compute_iaj_meat(struct tcpcb *tp, uint32_t cur_iaj) { - /* When accumulated IAJ reaches MAX_ACC_IAJ in milliseconds, + /* When accumulated IAJ reaches MAX_ACC_IAJ in milliseconds, * throttle the receive window to a minimum of MIN_IAJ_WIN packets */ #define MAX_ACC_IAJ (tcp_acc_iaj_high_thresh + tcp_acc_iaj_react_limit) @@ -496,66 +494,103 @@ void compute_iaj_meat(struct tcpcb *tp, uint32_t cur_iaj) uint32_t mean, temp; int32_t cur_iaj_dev; - cur_iaj_dev = (cur_iaj - tp->avg_iaj); - - /* Allow a jitter of "allowed_iaj" milliseconds. Some connections - * may have a constant jitter more than that. We detect this by + cur_iaj_dev = (cur_iaj - tp->avg_iaj); + + /* Allow a jitter of "allowed_iaj" milliseconds. Some connections + * may have a constant jitter more than that. We detect this by * using standard deviation. */ allowed_iaj = tp->avg_iaj + tp->std_dev_iaj; - if (allowed_iaj < tcp_allowed_iaj) + if (allowed_iaj < tcp_allowed_iaj) { allowed_iaj = tcp_allowed_iaj; + } - /* Initially when the connection starts, the senders congestion - * window is small. During this period we avoid throttling a - * connection because we do not have a good starting point for - * allowed_iaj. IAJ_IGNORE_PKTCNT is used to quietly gloss over + /* Initially when the connection starts, the senders congestion + * window is small. During this period we avoid throttling a + * connection because we do not have a good starting point for + * allowed_iaj. IAJ_IGNORE_PKTCNT is used to quietly gloss over * the first few packets. */ if (tp->iaj_pktcnt > IAJ_IGNORE_PKTCNT) { - if ( cur_iaj <= allowed_iaj ) { - if (tp->acc_iaj >= 2) + if (cur_iaj <= allowed_iaj) { + if (tp->acc_iaj >= 2) { acc_iaj = tp->acc_iaj - 2; - else + } else { acc_iaj = 0; - + } } else { acc_iaj = tp->acc_iaj + (cur_iaj - allowed_iaj); } - if (acc_iaj > MAX_ACC_IAJ) + if (acc_iaj > MAX_ACC_IAJ) { acc_iaj = MAX_ACC_IAJ; + } tp->acc_iaj = acc_iaj; } /* Compute weighted average where the history has a weight of - * 15 out of 16 and the current value has a weight of 1 out of 16. + * 15 out of 16 and the current value has a weight of 1 out of 16. * This will make the short-term measurements have more weight. * - * The addition of 8 will help to round-up the value + * The addition of 8 will help to round-up the value * instead of round-down */ - tp->avg_iaj = (((tp->avg_iaj << IAJ_DIV_SHIFT) - tp->avg_iaj) - + cur_iaj + IAJ_ROUNDUP_CONST) >> IAJ_DIV_SHIFT; + tp->avg_iaj = (((tp->avg_iaj << IAJ_DIV_SHIFT) - tp->avg_iaj) + + cur_iaj + IAJ_ROUNDUP_CONST) >> IAJ_DIV_SHIFT; /* Compute Root-mean-square of deviation where mean is a weighted - * average as described above. + * average as described above. */ temp = tp->std_dev_iaj * tp->std_dev_iaj; - mean = (((temp << IAJ_DIV_SHIFT) - temp) - + (cur_iaj_dev * cur_iaj_dev) - + IAJ_ROUNDUP_CONST) >> IAJ_DIV_SHIFT; - + mean = (((temp << IAJ_DIV_SHIFT) - temp) + + (cur_iaj_dev * cur_iaj_dev) + + IAJ_ROUNDUP_CONST) >> IAJ_DIV_SHIFT; + tp->std_dev_iaj = isqrt(mean); - DTRACE_TCP3(iaj, struct tcpcb *, tp, uint32_t, cur_iaj, - uint32_t, allowed_iaj); + DTRACE_TCP3(iaj, struct tcpcb *, tp, uint32_t, cur_iaj, + uint32_t, allowed_iaj); return; } #endif /* TRAFFIC_MGT */ -/* Check if enough amount of data has been acknowledged since +/* + * Perform rate limit check per connection per second + * tp->t_challengeack_last is the last_time diff was greater than 1sec + * tp->t_challengeack_count is the number of ACKs sent (within 1sec) + * Return TRUE if we shouldn't send the ACK due to rate limitation + * Return FALSE if it is still ok to send challenge ACK + */ +static boolean_t +tcp_is_ack_ratelimited(struct tcpcb *tp) +{ + boolean_t ret = TRUE; + uint32_t now = tcp_now; + int32_t diff = 0; + + diff = timer_diff(now, 0, tp->t_challengeack_last, 0); + /* If it is first time or diff > 1000ms, + * update the challengeack_last and reset the + * current count of ACKs + */ + if (tp->t_challengeack_last == 0 || diff >= 1000) { + tp->t_challengeack_last = now; + tp->t_challengeack_count = 0; + ret = FALSE; + } else if (tp->t_challengeack_count < tcp_challengeack_limit) { + ret = FALSE; + } + + /* Careful about wrap-around */ + if (ret == FALSE && (tp->t_challengeack_count + 1 > 0)) { + tp->t_challengeack_count++; + } + + return ret; +} + +/* Check if enough amount of data has been acknowledged since * bw measurement was started */ static void @@ -563,20 +598,37 @@ tcp_bwmeas_check(struct tcpcb *tp) { int32_t bw_meas_bytes; uint32_t bw, bytes, elapsed_time; + + if (SEQ_LEQ(tp->snd_una, tp->t_bwmeas->bw_start)) { + return; + } + bw_meas_bytes = tp->snd_una - tp->t_bwmeas->bw_start; - if ((tp->t_flagsext & TF_BWMEAS_INPROGRESS) != 0 && + if ((tp->t_flagsext & TF_BWMEAS_INPROGRESS) && bw_meas_bytes >= (int32_t)(tp->t_bwmeas->bw_size)) { bytes = bw_meas_bytes; elapsed_time = tcp_now - tp->t_bwmeas->bw_ts; if (elapsed_time > 0) { bw = bytes / elapsed_time; - if ( bw > 0) { + if (bw > 0) { if (tp->t_bwmeas->bw_sndbw > 0) { - tp->t_bwmeas->bw_sndbw = - (((tp->t_bwmeas->bw_sndbw << 3) - tp->t_bwmeas->bw_sndbw) + bw) >> 3; + tp->t_bwmeas->bw_sndbw = + (((tp->t_bwmeas->bw_sndbw << 3) + - tp->t_bwmeas->bw_sndbw) + + bw) >> 3; } else { tp->t_bwmeas->bw_sndbw = bw; } + + /* Store the maximum value */ + if (tp->t_bwmeas->bw_sndbw_max == 0) { + tp->t_bwmeas->bw_sndbw_max = + tp->t_bwmeas->bw_sndbw; + } else { + tp->t_bwmeas->bw_sndbw_max = + max(tp->t_bwmeas->bw_sndbw, + tp->t_bwmeas->bw_sndbw_max); + } } } tp->t_flagsext &= ~(TF_BWMEAS_INPROGRESS); @@ -585,7 +637,7 @@ tcp_bwmeas_check(struct tcpcb *tp) static int tcp_reass(struct tcpcb *tp, struct tcphdr *th, int *tlenp, struct mbuf *m, - struct ifnet *ifp) + struct ifnet *ifp, int *dowakeup) { struct tseg_qent *q; struct tseg_qent *p = NULL; @@ -594,39 +646,34 @@ tcp_reass(struct tcpcb *tp, struct tcphdr *th, int *tlenp, struct mbuf *m, struct inpcb *inp = tp->t_inpcb; struct socket *so = inp->inp_socket; int flags = 0; - int dowakeup = 0; struct mbuf *oodata = NULL; int copy_oodata = 0; + u_int16_t qlimit; boolean_t cell = IFNET_IS_CELLULAR(ifp); boolean_t wifi = (!cell && IFNET_IS_WIFI(ifp)); + boolean_t wired = (!wifi && IFNET_IS_WIRED(ifp)); + boolean_t dsack_set = FALSE; /* * Call with th==0 after become established to * force pre-ESTABLISHED data up to user socket. */ - if (th == NULL) + if (th == NULL) { goto present; - - /* If the reassembly queue already has entries or if we are going to add - * a new one, then the connection has reached a loss state. - * Reset the stretch-ack algorithm at this point. - */ - if ((tp->t_flags & TF_STRETCHACK) != 0) - tcp_reset_stretch_ack(tp); + } - /* When the connection reaches a loss state, we need to send more acks - * for a period of time so that the sender's congestion window will - * open. Wait until we see some packets on the connection before - * stretching acks again. + /* + * If the reassembly queue already has entries or if we are going + * to add a new one, then the connection has reached a loss state. + * Reset the stretch-ack algorithm at this point. */ - tp->t_flagsext |= TF_RCVUNACK_WAITSS; - tp->rcv_waitforss = 0; - + tcp_reset_stretch_ack(tp); #if TRAFFIC_MGT - if (tp->acc_iaj > 0) + if (tp->acc_iaj > 0) { reset_acc_iaj(tp); -#endif /* TRAFFIC_MGT */ + } +#endif /* TRAFFIC_MGT */ /* * Limit the number of segments in the reassembly queue to prevent @@ -635,30 +682,33 @@ tcp_reass(struct tcpcb *tp, struct tcphdr *th, int *tlenp, struct mbuf *m, * queue. Always keep one global queue entry spare to be able to * process the missing segment. */ + qlimit = min(max(100, so->so_rcv.sb_hiwat >> 10), + (TCP_AUTORCVBUF_MAX(ifp) >> 10)); if (th->th_seq != tp->rcv_nxt && - tcp_reass_qsize + 1 >= tcp_reass_maxseg) { + (tp->t_reassqlen + 1) >= qlimit) { tcp_reass_overflows++; tcpstat.tcps_rcvmemdrop++; m_freem(m); *tlenp = 0; - return (0); + return 0; } /* Allocate a new queue entry. If we can't, just drop the pkt. XXX */ - te = (struct tseg_qent *) zalloc_noblock(tcp_reass_zone); + te = (struct tseg_qent *) zalloc(tcp_reass_zone); if (te == NULL) { tcpstat.tcps_rcvmemdrop++; m_freem(m); - return (0); + return 0; } - tcp_reass_qsize++; + tp->t_reassqlen++; /* * Find a segment which begins after this one does. */ LIST_FOREACH(q, &tp->t_segq, tqe_q) { - if (SEQ_GT(q->tqe_th->th_seq, th->th_seq)) + if (SEQ_GT(q->tqe_th->th_seq, th->th_seq)) { break; + } p = q; } @@ -668,23 +718,43 @@ tcp_reass(struct tcpcb *tp, struct tcphdr *th, int *tlenp, struct mbuf *m, * segment. If it provides all of our data, drop us. */ if (p != NULL) { - register int i; + int i; /* conversion to int (in i) handles seq wraparound */ i = p->tqe_th->th_seq + p->tqe_len - th->th_seq; if (i > 0) { + if (TCP_DSACK_ENABLED(tp) && i > 1) { + /* + * Note duplicate data sequnce numbers + * to report in DSACK option + */ + tp->t_dsack_lseq = th->th_seq; + tp->t_dsack_rseq = th->th_seq + + min(i, *tlenp); + + /* + * Report only the first part of partial/ + * non-contiguous duplicate sequence space + */ + dsack_set = TRUE; + } if (i >= *tlenp) { tcpstat.tcps_rcvduppack++; tcpstat.tcps_rcvdupbyte += *tlenp; if (nstat_collect) { - nstat_route_rx(inp->inp_route.ro_rt, 1, *tlenp, NSTAT_RX_FLAG_DUPLICATE); - INP_ADD_STAT(inp, cell, wifi, rxpackets, 1); - INP_ADD_STAT(inp, cell, wifi, rxbytes, *tlenp); + nstat_route_rx(inp->inp_route.ro_rt, + 1, *tlenp, + NSTAT_RX_FLAG_DUPLICATE); + INP_ADD_STAT(inp, cell, wifi, wired, + rxpackets, 1); + INP_ADD_STAT(inp, cell, wifi, wired, + rxbytes, *tlenp); tp->t_stat.rxduplicatebytes += *tlenp; + inp_set_activity_bitmap(inp); } m_freem(m); zfree(tcp_reass_zone, te); te = NULL; - tcp_reass_qsize--; + tp->t_reassqlen--; /* * Try to present any queued data * at the left window edge to the user. @@ -698,13 +768,16 @@ tcp_reass(struct tcpcb *tp, struct tcphdr *th, int *tlenp, struct mbuf *m, th->th_seq += i; } } + tp->t_rcvoopack++; tcpstat.tcps_rcvoopack++; tcpstat.tcps_rcvoobyte += *tlenp; if (nstat_collect) { - nstat_route_rx(inp->inp_route.ro_rt, 1, *tlenp, NSTAT_RX_FLAG_OUT_OF_ORDER); - INP_ADD_STAT(inp, cell, wifi, rxpackets, 1); - INP_ADD_STAT(inp, cell, wifi, rxbytes, *tlenp); + nstat_route_rx(inp->inp_route.ro_rt, 1, *tlenp, + NSTAT_RX_FLAG_OUT_OF_ORDER); + INP_ADD_STAT(inp, cell, wifi, wired, rxpackets, 1); + INP_ADD_STAT(inp, cell, wifi, wired, rxbytes, *tlenp); tp->t_stat.rxoutoforderbytes += *tlenp; + inp_set_activity_bitmap(inp); } /* @@ -712,9 +785,32 @@ tcp_reass(struct tcpcb *tp, struct tcphdr *th, int *tlenp, struct mbuf *m, * if they are completely covered, dequeue them. */ while (q) { - register int i = (th->th_seq + *tlenp) - q->tqe_th->th_seq; - if (i <= 0) + int i = (th->th_seq + *tlenp) - q->tqe_th->th_seq; + if (i <= 0) { break; + } + + /* + * Report only the first part of partial/non-contiguous + * duplicate segment in dsack option. The variable + * dsack_set will be true if a previous entry has some of + * the duplicate sequence space. + */ + if (TCP_DSACK_ENABLED(tp) && i > 1 && !dsack_set) { + if (tp->t_dsack_lseq == 0) { + tp->t_dsack_lseq = q->tqe_th->th_seq; + tp->t_dsack_rseq = + tp->t_dsack_lseq + min(i, q->tqe_len); + } else { + /* + * this segment overlaps data in multple + * entries in the reassembly queue, move + * the right sequence number further. + */ + tp->t_dsack_rseq = + tp->t_dsack_rseq + min(i, q->tqe_len); + } + } if (i < q->tqe_len) { q->tqe_th->th_seq += i; q->tqe_len -= i; @@ -726,7 +822,7 @@ tcp_reass(struct tcpcb *tp, struct tcphdr *th, int *tlenp, struct mbuf *m, LIST_REMOVE(q, tqe_q); m_freem(q->tqe_m); zfree(tcp_reass_zone, q); - tcp_reass_qsize--; + tp->t_reassqlen--; q = nq; } @@ -741,107 +837,134 @@ tcp_reass(struct tcpcb *tp, struct tcphdr *th, int *tlenp, struct mbuf *m, LIST_INSERT_AFTER(p, te, tqe_q); } - /* + /* * New out-of-order data exists, and is pointed to by - * queue entry te. Set copy_oodata to 1 so out-of-order data - * can be copied off to sockbuf after in-order data + * queue entry te. Set copy_oodata to 1 so out-of-order data + * can be copied off to sockbuf after in-order data * is copied off. */ - if (!(so->so_state & SS_CANTRCVMORE)) + if (!(so->so_state & SS_CANTRCVMORE)) { copy_oodata = 1; + } present: /* * Present data to user, advancing rcv_nxt through * completed sequence space. */ - if (!TCPS_HAVEESTABLISHED(tp->t_state)) - return (0); + if (!TCPS_HAVEESTABLISHED(tp->t_state)) { + return 0; + } q = LIST_FIRST(&tp->t_segq); if (!q || q->tqe_th->th_seq != tp->rcv_nxt) { /* Stop using LRO once out of order packets arrive */ if (tp->t_flagsext & TF_LRO_OFFLOADED) { tcp_lro_remove_state(inp->inp_laddr, inp->inp_faddr, - th->th_dport, th->th_sport); - tp->t_flagsext &= ~TF_LRO_OFFLOADED; + th->th_dport, th->th_sport); + tp->t_flagsext &= ~TF_LRO_OFFLOADED; } /* - * continue processing if out-of-order data + * continue processing if out-of-order data * can be delivered */ - if (q && (so->so_flags & SOF_ENABLE_MSGS)) + if (q && (so->so_flags & SOF_ENABLE_MSGS)) { goto msg_unordered_delivery; + } + + return 0; + } + + /* + * If there is already another thread doing reassembly for this + * connection, it is better to let it finish the job -- + * (radar 16316196) + */ + if (tp->t_flagsext & TF_REASS_INPROG) { + return 0; + } + + tp->t_flagsext |= TF_REASS_INPROG; + /* lost packet was recovered, so ooo data can be returned */ + tcpstat.tcps_recovered_pkts++; - return (0); - } do { tp->rcv_nxt += q->tqe_len; flags = q->tqe_th->th_flags & TH_FIN; - nq = LIST_NEXT(q, tqe_q); LIST_REMOVE(q, tqe_q); if (so->so_state & SS_CANTRCVMORE) { m_freem(q->tqe_m); } else { + /* + * The mbuf may be freed after it has been added to the + * receive socket buffer so we reinitialize th to point + * to a safe copy of the TCP header + */ + struct tcphdr saved_tcphdr = {}; + so_recv_data_stat(so, q->tqe_m, 0); /* XXXX */ if (so->so_flags & SOF_ENABLE_MSGS) { - /* - * Append the inorder data as a message to the - * receive socket buffer. Also check to see if - * the data we are about to deliver is the same - * data that we wanted to pass up to the user - * out of order. If so, reset copy_oodata -- + /* + * Append the inorder data as a message to the + * receive socket buffer. Also check to see if + * the data we are about to deliver is the same + * data that we wanted to pass up to the user + * out of order. If so, reset copy_oodata -- * the received data filled a gap, and * is now in order! */ - if (q == te) + if (q == te) { copy_oodata = 0; + } + } + memcpy(&saved_tcphdr, th, sizeof(struct tcphdr)); + if (sbappendstream_rcvdemux(so, q->tqe_m, + q->tqe_th->th_seq - (tp->irs + 1), 0)) { + *dowakeup = 1; } - if (sbappendstream_rcvdemux(so, q->tqe_m, - q->tqe_th->th_seq - (tp->irs + 1), 0)) - dowakeup = 1; - if (tp->t_flagsext & TF_LRO_OFFLOADED) { - tcp_update_lro_seq(tp->rcv_nxt, - inp->inp_laddr, inp->inp_faddr, - th->th_dport, th->th_sport); + th = &saved_tcphdr; + + if (tp->t_flagsext & TF_LRO_OFFLOADED) { + tcp_update_lro_seq(tp->rcv_nxt, + inp->inp_laddr, inp->inp_faddr, + th->th_dport, th->th_sport); } } zfree(tcp_reass_zone, q); - tcp_reass_qsize--; - q = nq; + tp->t_reassqlen--; + q = LIST_FIRST(&tp->t_segq); } while (q && q->tqe_th->th_seq == tp->rcv_nxt); + tp->t_flagsext &= ~TF_REASS_INPROG; #if INET6 if ((inp->inp_vflag & INP_IPV6) != 0) { - KERNEL_DEBUG(DBG_LAYER_BEG, - ((inp->inp_fport << 16) | inp->inp_lport), - (((inp->in6p_laddr.s6_addr16[0] & 0xffff) << 16) | - (inp->in6p_faddr.s6_addr16[0] & 0xffff)), - 0,0,0); - } - else + ((inp->inp_fport << 16) | inp->inp_lport), + (((inp->in6p_laddr.s6_addr16[0] & 0xffff) << 16) | + (inp->in6p_faddr.s6_addr16[0] & 0xffff)), + 0, 0, 0); + } else #endif { KERNEL_DEBUG(DBG_LAYER_BEG, - ((inp->inp_fport << 16) | inp->inp_lport), - (((inp->inp_laddr.s_addr & 0xffff) << 16) | - (inp->inp_faddr.s_addr & 0xffff)), - 0,0,0); + ((inp->inp_fport << 16) | inp->inp_lport), + (((inp->inp_laddr.s_addr & 0xffff) << 16) | + (inp->inp_faddr.s_addr & 0xffff)), + 0, 0, 0); } msg_unordered_delivery: /* Deliver out-of-order data as a message */ if (te && (so->so_flags & SOF_ENABLE_MSGS) && copy_oodata && te->tqe_len) { - /* - * make a copy of the mbuf to be delivered up to + /* + * make a copy of the mbuf to be delivered up to * the user, and add it to the sockbuf */ oodata = m_copym(te->tqe_m, 0, M_COPYALL, M_DONTWAIT); if (oodata != NULL) { - if (sbappendmsgstream_rcv(&so->so_rcv, oodata, - te->tqe_th->th_seq - (tp->irs + 1), 1)) { - dowakeup = 1; + if (sbappendmsgstream_rcv(&so->so_rcv, oodata, + te->tqe_th->th_seq - (tp->irs + 1), 1)) { + *dowakeup = 1; tcpstat.tcps_msg_unopkts++; } else { tcpstat.tcps_msg_unoappendfail++; @@ -849,46 +972,65 @@ msg_unordered_delivery: } } - if (dowakeup) - sorwakeup(so); /* done with socket lock held */ - return (flags); + return flags; } /* - * Reduce congestion window. + * Reduce congestion window -- used when ECN is seen or when a tail loss + * probe recovers the last packet. */ static void tcp_reduce_congestion_window( - struct tcpcb *tp) + struct tcpcb *tp) { /* * If the current tcp cc module has * defined a hook for tasks to run * before entering FR, call it */ - if (CC_ALGO(tp)->pre_fr != NULL) + if (CC_ALGO(tp)->pre_fr != NULL) { CC_ALGO(tp)->pre_fr(tp); + } ENTER_FASTRECOVERY(tp); - tp->snd_recover = tp->snd_max; + if (tp->t_flags & TF_SENTFIN) { + tp->snd_recover = tp->snd_max - 1; + } else { + tp->snd_recover = tp->snd_max; + } tp->t_timer[TCPT_REXMT] = 0; + tp->t_timer[TCPT_PTO] = 0; tp->t_rtttime = 0; - tp->ecn_flags |= TE_SENDCWR; - tp->snd_cwnd = tp->snd_ssthresh + - tp->t_maxseg * tcprexmtthresh; + if (tp->t_flagsext & TF_CWND_NONVALIDATED) { + tcp_cc_adjust_nonvalidated_cwnd(tp); + } else { + tp->snd_cwnd = tp->snd_ssthresh + + tp->t_maxseg * tcprexmtthresh; + } } /* - * The application wants to get an event if there - * is a stall during read. Set the initial keepalive - * timeout to be equal to twice RTO. + * This function is called upon reception of data on a socket. It's purpose is + * to handle the adaptive keepalive timers that monitor whether the connection + * is making progress. First the adaptive read-timer, second the TFO probe-timer. + * + * The application wants to get an event if there is a stall during read. + * Set the initial keepalive timeout to be equal to twice RTO. + * + * If the outgoing interface is in marginal conditions, we need to + * enable read probes for that too. */ static inline void -tcp_adaptive_rwtimo_check(struct tcpcb *tp, int tlen) +tcp_adaptive_rwtimo_check(struct tcpcb *tp, int tlen) { - if (tp->t_adaptive_rtimo > 0 && tlen > 0 && - tp->t_state == TCPS_ESTABLISHED) { - tp->t_timer[TCPT_KEEP] = OFFSET_FROM_START(tp, - (TCP_REXMTVAL(tp) << 1)); + struct ifnet *outifp = tp->t_inpcb->inp_last_outifp; + + if ((tp->t_adaptive_rtimo > 0 || + (outifp != NULL && + (outifp->if_eflags & IFEF_PROBE_CONNECTIVITY))) + && tlen > 0 && + tp->t_state == TCPS_ESTABLISHED) { + tp->t_timer[TCPT_KEEP] = OFFSET_FROM_START(tp, + (TCP_REXMTVAL(tp) << 1)); tp->t_flagsext |= TF_DETECT_READSTALL; tp->t_rtimo_probes = 0; } @@ -897,8 +1039,8 @@ tcp_adaptive_rwtimo_check(struct tcpcb *tp, int tlen) inline void tcp_keepalive_reset(struct tcpcb *tp) { - tp->t_timer[TCPT_KEEP] = OFFSET_FROM_START(tp, - TCP_CONN_KEEPIDLE(tp)); + tp->t_timer[TCPT_KEEP] = OFFSET_FROM_START(tp, + TCP_CONN_KEEPIDLE(tp)); tp->t_flagsext &= ~(TF_DETECT_READSTALL); tp->t_rtimo_probes = 0; } @@ -912,7 +1054,7 @@ int tcp6_input(struct mbuf **mp, int *offp, int proto) { #pragma unused(proto) - register struct mbuf *m = *mp; + struct mbuf *m = *mp; uint32_t ia6_flags; struct ifnet *ifp = m->m_pkthdr.rcvif; @@ -936,17 +1078,17 @@ tcp6_input(struct mbuf **mp, int *offp, int proto) IF_TCP_STATINC(ifp, icmp6unreach); - return (IPPROTO_DONE); + return IPPROTO_DONE; } } tcp_input(m, *offp); - return (IPPROTO_DONE); + return IPPROTO_DONE; } #endif /* Depending on the usage of mbuf space in the system, this function - * will return true or false. This is used to determine if a socket + * will return true or false. This is used to determine if a socket * buffer can take more memory from the system for auto-tuning or not. */ u_int8_t @@ -954,7 +1096,7 @@ tcp_cansbgrow(struct sockbuf *sb) { /* Calculate the host level space limit in terms of MSIZE buffers. * We can use a maximum of half of the available mbuf space for - * socket buffers. + * socket buffers. */ u_int32_t mblim = ((nmbclusters >> 1) << (MCLSHIFT - MSIZESHIFT)); @@ -965,72 +1107,76 @@ tcp_cansbgrow(struct sockbuf *sb) u_int32_t sbspacelim = ((nmbclusters >> 4) << MCLSHIFT); if ((total_sbmb_cnt < mblim) && - (sb->sb_hiwat < sbspacelim)) { - return(1); + (sb->sb_hiwat < sbspacelim)) { + return 1; + } else { + OSIncrementAtomic64(&sbmb_limreached); } - return(0); + return 0; } static void tcp_sbrcv_reserve(struct tcpcb *tp, struct sockbuf *sbrcv, - u_int32_t newsize, u_int32_t idealsize) + u_int32_t newsize, u_int32_t idealsize, u_int32_t rcvbuf_max) { - /* newsize should not exceed max */ - newsize = min(newsize, tcp_autorcvbuf_max); + newsize = min(newsize, rcvbuf_max); - /* The receive window scale negotiated at the - * beginning of the connection will also set a + /* The receive window scale negotiated at the + * beginning of the connection will also set a * limit on the socket buffer size */ newsize = min(newsize, TCP_MAXWIN << tp->rcv_scale); /* Set new socket buffer size */ if (newsize > sbrcv->sb_hiwat && - (sbreserve(sbrcv, newsize) == 1)) { - sbrcv->sb_idealsize = min(max(sbrcv->sb_idealsize, - (idealsize != 0) ? idealsize : newsize), - tcp_autorcvbuf_max); + (sbreserve(sbrcv, newsize) == 1)) { + sbrcv->sb_idealsize = min(max(sbrcv->sb_idealsize, + (idealsize != 0) ? idealsize : newsize), rcvbuf_max); - /* Again check the limit set by the advertised - * window scale + /* Again check the limit set by the advertised + * window scale */ - sbrcv->sb_idealsize = min(sbrcv->sb_idealsize, - TCP_MAXWIN << tp->rcv_scale); + sbrcv->sb_idealsize = min(sbrcv->sb_idealsize, + TCP_MAXWIN << tp->rcv_scale); } } -/* +/* * This function is used to grow a receive socket buffer. It * will take into account system-level memory usage and the * bandwidth available on the link to make a decision. */ static void -tcp_sbrcv_grow(struct tcpcb *tp, struct sockbuf *sbrcv, - struct tcpopt *to, u_int32_t pktlen) { - +tcp_sbrcv_grow(struct tcpcb *tp, struct sockbuf *sbrcv, + struct tcpopt *to, u_int32_t pktlen, u_int32_t rcvbuf_max) +{ + struct socket *so = sbrcv->sb_so; + /* * Do not grow the receive socket buffer if * - auto resizing is disabled, globally or on this socket - * - the high water mark has already reached the maximum - * - the stream is in background and receive side is being + * - the high water mark already reached the maximum + * - the stream is in background and receive side is being * throttled * - if there are segments in reassembly queue indicating loss, - * do not need to increase recv window during recovery as more - * data is not going to be sent. + * do not need to increase recv window during recovery as more + * data is not going to be sent. A duplicate ack sent during + * recovery should not change the receive window */ if (tcp_do_autorcvbuf == 0 || - (sbrcv->sb_flags & SB_AUTOSIZE) == 0 || - tcp_cansbgrow(sbrcv) == 0 || - sbrcv->sb_hiwat >= tcp_autorcvbuf_max || - (tp->t_flagsext & TF_RECV_THROTTLE) || - !LIST_EMPTY(&tp->t_segq)) { + (sbrcv->sb_flags & SB_AUTOSIZE) == 0 || + tcp_cansbgrow(sbrcv) == 0 || + sbrcv->sb_hiwat >= rcvbuf_max || + (tp->t_flagsext & TF_RECV_THROTTLE) || + (so->so_flags1 & SOF1_EXTEND_BK_IDLE_WANTED) || + !LIST_EMPTY(&tp->t_segq)) { /* Can not resize the socket buffer, just return */ goto out; } if (TSTMP_GT(tcp_now, - tp->rfbuf_ts + TCPTV_RCVBUFIDLE)) { + tp->rfbuf_ts + TCPTV_RCVBUFIDLE)) { /* If there has been an idle period in the * connection, just restart the measurement */ @@ -1042,53 +1188,77 @@ tcp_sbrcv_grow(struct tcpcb *tp, struct sockbuf *sbrcv, * Timestamp option is not supported on this connection. * If the connection reached a state to indicate that * the receive socket buffer needs to grow, increase - * the high water mark. - */ - if (TSTMP_GEQ(tcp_now, - tp->rfbuf_ts + TCPTV_RCVNOTS_QUANTUM)) { - if (tp->rfbuf_cnt >= TCP_RCVNOTS_BYTELEVEL) { + * the high water mark. + */ + if (TSTMP_GEQ(tcp_now, + tp->rfbuf_ts + TCPTV_RCVNOTS_QUANTUM)) { + if (tp->rfbuf_cnt + pktlen >= TCP_RCVNOTS_BYTELEVEL) { tcp_sbrcv_reserve(tp, sbrcv, - tcp_autorcvbuf_max, 0); + tcp_autorcvbuf_max, 0, + tcp_autorcvbuf_max); } goto out; } else { tp->rfbuf_cnt += pktlen; return; - } + } } else if (to->to_tsecr != 0) { - /* If the timestamp shows that one RTT has + /* + * If the timestamp shows that one RTT has * completed, we can stop counting the * bytes. Here we consider increasing - * the socket buffer if it fits the following - * criteria: - * 1. the bandwidth measured in last rtt, is more - * than half of sb_hiwat, this will help to scale the - * buffer according to the bandwidth on the link. - * 2. the space left in sbrcv is less than - * one forth of the bandwidth measured in last rtt, this - * will help to accommodate an application reading slowly. + * the socket buffer if the bandwidth measured in + * last rtt, is more than half of sb_hiwat, this will + * help to scale the buffer according to the bandwidth + * on the link. */ if (TSTMP_GEQ(to->to_tsecr, tp->rfbuf_ts)) { - if ((tp->rfbuf_cnt > (sbrcv->sb_hiwat - - (sbrcv->sb_hiwat >> tcp_rbuf_hiwat_shift)) || - (sbrcv->sb_hiwat - sbrcv->sb_cc) < - (tp->rfbuf_cnt >> tcp_rbuf_win_shift))) { - u_int32_t rcvbuf_inc; + if (tp->rfbuf_cnt + pktlen > (sbrcv->sb_hiwat - + (sbrcv->sb_hiwat >> 1))) { + tp->rfbuf_cnt += pktlen; + int32_t rcvbuf_inc, min_incr; /* - * Increment the receive window by a multiple of - * maximum sized segments. This will prevent a - * connection from sending smaller segments on - * wire if it is limited by the receive window. + * Increment the receive window by a + * multiple of maximum sized segments. + * This will prevent a connection from + * sending smaller segments on wire if it + * is limited by the receive window. * - * Set the ideal size based on current bandwidth - * measurements. We set the ideal size on receive - * socket buffer to be twice the bandwidth delay - * product. + * Set the ideal size based on current + * bandwidth measurements. We set the + * ideal size on receive socket buffer to + * be twice the bandwidth delay product. */ - rcvbuf_inc = tp->t_maxseg << tcp_autorcvbuf_inc_shift; + rcvbuf_inc = (tp->rfbuf_cnt << 1) + - sbrcv->sb_hiwat; + + /* + * Make the increment equal to 8 segments + * at least + */ + min_incr = tp->t_maxseg << tcp_autorcvbuf_inc_shift; + if (rcvbuf_inc < min_incr) { + rcvbuf_inc = min_incr; + } + + rcvbuf_inc = + (rcvbuf_inc / tp->t_maxseg) * tp->t_maxseg; tcp_sbrcv_reserve(tp, sbrcv, - sbrcv->sb_hiwat + rcvbuf_inc, - (tp->rfbuf_cnt * 2)); + sbrcv->sb_hiwat + rcvbuf_inc, + (tp->rfbuf_cnt << 1), rcvbuf_max); + } + /* Measure instantaneous receive bandwidth */ + if (tp->t_bwmeas != NULL && tp->rfbuf_cnt > 0 && + TSTMP_GT(tcp_now, tp->rfbuf_ts)) { + u_int32_t rcv_bw; + rcv_bw = tp->rfbuf_cnt / + (int)(tcp_now - tp->rfbuf_ts); + if (tp->t_bwmeas->bw_rcvbw_max == 0) { + tp->t_bwmeas->bw_rcvbw_max = rcv_bw; + } else { + tp->t_bwmeas->bw_rcvbw_max = max( + tp->t_bwmeas->bw_rcvbw_max, rcv_bw); + } } goto out; } else { @@ -1105,13 +1275,14 @@ out: /* This function will trim the excess space added to the socket buffer * to help a slow-reading app. The ideal-size of a socket buffer depends - * on the link bandwidth or it is set by an application and we aim to + * on the link bandwidth or it is set by an application and we aim to * reach that size. */ void -tcp_sbrcv_trim(struct tcpcb *tp, struct sockbuf *sbrcv) { +tcp_sbrcv_trim(struct tcpcb *tp, struct sockbuf *sbrcv) +{ if (tcp_do_autorcvbuf == 1 && sbrcv->sb_idealsize > 0 && - sbrcv->sb_hiwat > sbrcv->sb_idealsize) { + sbrcv->sb_hiwat > sbrcv->sb_idealsize) { int32_t trim; /* compute the difference between ideal and current sizes */ u_int32_t diff = sbrcv->sb_hiwat - sbrcv->sb_idealsize; @@ -1120,25 +1291,27 @@ tcp_sbrcv_trim(struct tcpcb *tp, struct sockbuf *sbrcv) { * this connection. */ u_int32_t advwin = tp->rcv_adv - tp->rcv_nxt; - + /* How much can we trim the receive socket buffer? * 1. it can not be trimmed beyond the max rcv win advertised - * 2. if possible, leave 1/16 of bandwidth*delay to + * 2. if possible, leave 1/16 of bandwidth*delay to * avoid closing the win completely */ u_int32_t leave = max(advwin, (sbrcv->sb_idealsize >> 4)); /* Sometimes leave can be zero, in that case leave at least - * a few segments worth of space. + * a few segments worth of space. */ - if (leave == 0) + if (leave == 0) { leave = tp->t_maxseg << tcp_autorcvbuf_inc_shift; - + } + trim = sbrcv->sb_hiwat - (sbrcv->sb_cc + leave); trim = imin(trim, (int32_t)diff); - if (trim > 0) + if (trim > 0) { sbreserve(sbrcv, (sbrcv->sb_hiwat - trim)); + } } } @@ -1149,12 +1322,13 @@ tcp_sbrcv_trim(struct tcpcb *tp, struct sockbuf *sbrcv) { * to hold more mbufs for that connection than what the cwnd will allow. */ void -tcp_sbsnd_trim(struct sockbuf *sbsnd) { - if (tcp_do_autosendbuf == 1 && - ((sbsnd->sb_flags & (SB_AUTOSIZE | SB_TRIM)) == - (SB_AUTOSIZE | SB_TRIM)) && - (sbsnd->sb_idealsize > 0) && - (sbsnd->sb_hiwat > sbsnd->sb_idealsize)) { +tcp_sbsnd_trim(struct sockbuf *sbsnd) +{ + if (tcp_do_autosendbuf == 1 && + ((sbsnd->sb_flags & (SB_AUTOSIZE | SB_TRIM)) == + (SB_AUTOSIZE | SB_TRIM)) && + (sbsnd->sb_idealsize > 0) && + (sbsnd->sb_hiwat > sbsnd->sb_idealsize)) { u_int32_t trim = 0; if (sbsnd->sb_cc <= sbsnd->sb_idealsize) { trim = sbsnd->sb_hiwat - sbsnd->sb_idealsize; @@ -1163,105 +1337,158 @@ tcp_sbsnd_trim(struct sockbuf *sbsnd) { } sbreserve(sbsnd, (sbsnd->sb_hiwat - trim)); } - if (sbsnd->sb_hiwat <= sbsnd->sb_idealsize) + if (sbsnd->sb_hiwat <= sbsnd->sb_idealsize) { sbsnd->sb_flags &= ~(SB_TRIM); + } } -/* +/* * If timestamp option was not negotiated on this connection * and this connection is on the receiving side of a stream * then we can not measure the delay on the link accurately. * Instead of enabling automatic receive socket buffer * resizing, just give more space to the receive socket buffer. */ -static inline void -tcp_sbrcv_tstmp_check(struct tcpcb *tp) { +static inline void +tcp_sbrcv_tstmp_check(struct tcpcb *tp) +{ struct socket *so = tp->t_inpcb->inp_socket; u_int32_t newsize = 2 * tcp_recvspace; struct sockbuf *sbrcv = &so->so_rcv; if ((tp->t_flags & (TF_REQ_TSTMP | TF_RCVD_TSTMP)) != - (TF_REQ_TSTMP | TF_RCVD_TSTMP) && - (sbrcv->sb_flags & SB_AUTOSIZE) != 0) { - tcp_sbrcv_reserve(tp, sbrcv, newsize, 0); + (TF_REQ_TSTMP | TF_RCVD_TSTMP) && + (sbrcv->sb_flags & SB_AUTOSIZE) != 0) { + tcp_sbrcv_reserve(tp, sbrcv, newsize, 0, newsize); } } -/* A receiver will evaluate the flow of packets on a connection - * to see if it can reduce ack traffic. The receiver will start +/* A receiver will evaluate the flow of packets on a connection + * to see if it can reduce ack traffic. The receiver will start * stretching acks if all of the following conditions are met: * 1. tcp_delack_enabled is set to 3 * 2. If the bytes received in the last 100ms is greater than a threshold * defined by maxseg_unacked * 3. If the connection has not been idle for tcp_maxrcvidle period. - * 4. If the connection has seen enough packets to let the slow-start + * 4. If the connection has seen enough packets to let the slow-start * finish after connection establishment or after some packet loss. * * The receiver will stop stretching acks if there is congestion/reordering - * as indicated by packets on reassembly queue or an ECN. If the delayed-ack - * timer fires while stretching acks, it means that the packet flow has gone + * as indicated by packets on reassembly queue or an ECN. If the delayed-ack + * timer fires while stretching acks, it means that the packet flow has gone * below the threshold defined by maxseg_unacked and the receiver will stop - * stretching acks. The receiver gets no indication when slow-start is completed - * or when the connection reaches an idle state. That is why we use - * tcp_rcvsspktcnt to cover slow-start and tcp_maxrcvidle to identify idle + * stretching acks. The receiver gets no indication when slow-start is completed + * or when the connection reaches an idle state. That is why we use + * tcp_rcvsspktcnt to cover slow-start and tcp_maxrcvidle to identify idle * state. */ static inline int -tcp_stretch_ack_enable(struct tcpcb *tp) +tcp_stretch_ack_enable(struct tcpcb *tp, int thflags) { - if (!(tp->t_flagsext & TF_NOSTRETCHACK) && - tp->rcv_by_unackwin >= (maxseg_unacked * tp->t_maxseg) && - TSTMP_GT(tp->rcv_unackwin + tcp_maxrcvidle, tcp_now) && - (!(tp->t_flagsext & TF_RCVUNACK_WAITSS) || - (tp->rcv_waitforss >= tcp_rcvsspktcnt))) { - return(1); - } - - return(0); + if (tp->rcv_by_unackwin >= (maxseg_unacked * tp->t_maxseg) && + TSTMP_GEQ(tp->rcv_unackwin, tcp_now)) { + tp->t_flags |= TF_STREAMING_ON; + } else { + tp->t_flags &= ~TF_STREAMING_ON; + } + + /* If there has been an idle time, reset streaming detection */ + if (TSTMP_GT(tcp_now, tp->rcv_unackwin + tcp_maxrcvidle)) { + tp->t_flags &= ~TF_STREAMING_ON; + } + + /* + * If there are flags other than TH_ACK set, reset streaming + * detection + */ + if (thflags & ~TH_ACK) { + tp->t_flags &= ~TF_STREAMING_ON; + } + + if (tp->t_flagsext & TF_DISABLE_STRETCHACK) { + if (tp->rcv_nostrack_pkts >= TCP_STRETCHACK_ENABLE_PKTCNT) { + tp->t_flagsext &= ~TF_DISABLE_STRETCHACK; + tp->rcv_nostrack_pkts = 0; + tp->rcv_nostrack_ts = 0; + } else { + tp->rcv_nostrack_pkts++; + } + } + + if (!(tp->t_flagsext & (TF_NOSTRETCHACK | TF_DISABLE_STRETCHACK)) && + (tp->t_flags & TF_STREAMING_ON) && + (!(tp->t_flagsext & TF_RCVUNACK_WAITSS) || + (tp->rcv_waitforss >= tcp_rcvsspktcnt))) { + return 1; + } + + return 0; } -/* Reset the state related to stretch-ack algorithm. This will make +/* + * Reset the state related to stretch-ack algorithm. This will make * the receiver generate an ack every other packet. The receiver - * will start re-evaluating the rate at which packets come to decide + * will start re-evaluating the rate at which packets come to decide * if it can benefit by lowering the ack traffic. */ void tcp_reset_stretch_ack(struct tcpcb *tp) { - tp->t_flags &= ~(TF_STRETCHACK); + tp->t_flags &= ~(TF_STRETCHACK | TF_STREAMING_ON); tp->rcv_by_unackwin = 0; + tp->rcv_by_unackhalfwin = 0; tp->rcv_unackwin = tcp_now + tcp_rcvunackwin; + + /* + * When there is packet loss or packet re-ordering or CWR due to + * ECN, the sender's congestion window is reduced. In these states, + * generate an ack for every other packet for some time to allow + * the sender's congestion window to grow. + */ + tp->t_flagsext |= TF_RCVUNACK_WAITSS; + tp->rcv_waitforss = 0; } /* - * The last packet was a retransmission, check if this ack + * The last packet was a retransmission, check if this ack * indicates that the retransmission was spurious. - * + * * If the connection supports timestamps, we could use it to * detect if the last retransmit was not needed. Otherwise, - * we check if the ACK arrived within RTT/2 window, then it + * we check if the ACK arrived within RTT/2 window, then it * was a mistake to do the retransmit in the first place. * - * This function will return 1 if it is a spurious retransmit, - * 0 otherwise. + * This function will return 1 if it is a spurious retransmit, + * 0 otherwise. */ -static int -tcp_detect_bad_rexmt(struct tcpcb *tp, struct tcpopt *to) +int +tcp_detect_bad_rexmt(struct tcpcb *tp, struct tcphdr *th, + struct tcpopt *to, u_int32_t rxtime) { int32_t tdiff, bad_rexmt_win; - tdiff = (int32_t)(tcp_now - tp->t_rxtstart); bad_rexmt_win = (tp->t_srtt >> (TCP_RTT_SHIFT + 1)); - if (TSTMP_SUPPORTED(tp) && tp->t_rxtstart > 0 && - (to->to_flags & TOF_TS) != 0 && - to->to_tsecr != 0 && - TSTMP_LT(to->to_tsecr, tp->t_rxtstart)) { - return (1); - } else if (tp->t_rxtshift == 1 && - tdiff < bad_rexmt_win) { - return(1); + /* If the ack has ECN CE bit, then cwnd has to be adjusted */ + if (TCP_ECN_ENABLED(tp) && (th->th_flags & TH_ECE)) { + return 0; + } + if (TSTMP_SUPPORTED(tp)) { + if (rxtime > 0 && (to->to_flags & TOF_TS) + && to->to_tsecr != 0 + && TSTMP_LT(to->to_tsecr, rxtime)) { + return 1; + } + } else { + if ((tp->t_rxtshift == 1 + || (tp->t_flagsext & TF_SENT_TLPROBE)) + && rxtime > 0) { + tdiff = (int32_t)(tcp_now - rxtime); + if (tdiff < bad_rexmt_win) { + return 1; + } + } } - return(0); + return 0; } @@ -1284,27 +1511,30 @@ tcp_bad_rexmt_restore_state(struct tcpcb *tp, struct tcphdr *th) tp->snd_ssthresh = tp->snd_ssthresh_prev; /* Initialize cwnd to the initial window */ - if (CC_ALGO(tp)->cwnd_init != NULL) + if (CC_ALGO(tp)->cwnd_init != NULL) { CC_ALGO(tp)->cwnd_init(tp); + } tp->snd_cwnd = fsize + min(acked, tp->snd_cwnd); - } else { tp->snd_cwnd = tp->snd_cwnd_prev; tp->snd_ssthresh = tp->snd_ssthresh_prev; - if (tp->t_flags & TF_WASFRECOVERY) + if (tp->t_flags & TF_WASFRECOVERY) { ENTER_FASTRECOVERY(tp); + } + + /* Do not use the loss flight size in this case */ + tp->t_lossflightsize = 0; } + tp->snd_cwnd = max(tp->snd_cwnd, TCP_CC_CWND_INIT_BYTES); tp->snd_recover = tp->snd_recover_prev; tp->snd_nxt = tp->snd_max; - tp->t_rxtshift = 0; - tp->t_rxtstart = 0; /* Fix send socket buffer to reflect the change in cwnd */ tcp_bad_rexmt_fix_sndbuf(tp); /* - * This RTT might reflect the extra delay induced + * This RTT might reflect the extra delay induced * by the network. Skip using this sample for RTO * calculation and mark the connection so we can * recompute RTT when the next eligible sample is @@ -1315,89 +1545,477 @@ tcp_bad_rexmt_restore_state(struct tcpcb *tp, struct tcphdr *th) tp->t_rtttime = 0; } -void -tcp_input(m, off0) - struct mbuf *m; - int off0; +/* + * If the previous packet was sent in retransmission timer, and it was + * not needed, then restore the congestion window to the state before that + * transmission. + * + * If the last packet was sent in tail loss probe timeout, check if that + * recovered the last packet. If so, that will indicate a real loss and + * the congestion window needs to be lowered. + */ +static void +tcp_bad_rexmt_check(struct tcpcb *tp, struct tcphdr *th, struct tcpopt *to) { - register struct tcphdr *th; - register struct ip *ip = NULL; - register struct inpcb *inp; - u_char *optp = NULL; - int optlen = 0; - int tlen, off; - int drop_hdrlen; - register struct tcpcb *tp = 0; - register int thflags; - struct socket *so = 0; - int todrop, acked, ourfinisacked, needoutput = 0; - struct in_addr laddr; -#if INET6 - struct in6_addr laddr6; -#endif - int dropsocket = 0; - int iss = 0, nosock = 0; - u_int32_t tiwin, sack_bytes_acked = 0; - struct tcpopt to; /* options in this segment */ - struct sockaddr_in *next_hop = NULL; -#if TCPDEBUG - short ostate = 0; -#endif - struct m_tag *fwd_tag; - u_char ip_ecn = IPTOS_ECN_NOTECT; - unsigned int ifscope, nocell = 0; - uint8_t isconnected, isdisconnected; - struct ifnet *ifp = m->m_pkthdr.rcvif; - int pktf_sw_lro_pkt = (m->m_pkthdr.pkt_flags & PKTF_SW_LRO_PKT) ? 1 : 0; - int nlropkts = (pktf_sw_lro_pkt == 1) ? m->m_pkthdr.lro_npkts : 1; - int turnoff_lro = 0, win; -#if MPTCP - struct mptcb *mp_tp = NULL; - uint16_t mptcp_csum = 0; -#endif /* MPTCP */ - boolean_t cell = IFNET_IS_CELLULAR(ifp); - boolean_t wifi = (!cell && IFNET_IS_WIFI(ifp)); - -#define TCP_INC_VAR(stat, npkts) do { \ - stat += npkts; \ -} while (0) - - TCP_INC_VAR(tcpstat.tcps_rcvtotal, nlropkts); + if (tp->t_rxtshift > 0 && + tcp_detect_bad_rexmt(tp, th, to, tp->t_rxtstart)) { + ++tcpstat.tcps_sndrexmitbad; + tcp_bad_rexmt_restore_state(tp, th); + tcp_ccdbg_trace(tp, th, TCP_CC_BAD_REXMT_RECOVERY); + } else if ((tp->t_flagsext & TF_SENT_TLPROBE) + && tp->t_tlphighrxt > 0 + && SEQ_GEQ(th->th_ack, tp->t_tlphighrxt) + && !tcp_detect_bad_rexmt(tp, th, to, tp->t_tlpstart)) { + /* + * check DSACK information also to make sure that + * the TLP was indeed needed + */ + if (tcp_rxtseg_dsack_for_tlp(tp)) { + /* + * received a DSACK to indicate that TLP was + * not needed + */ + tcp_rxtseg_clean(tp); + goto out; + } - /* Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. */ - if (!SLIST_EMPTY(&m->m_pkthdr.tags)) { - fwd_tag = m_tag_locate(m, KERNEL_MODULE_TAG_ID, - KERNEL_TAG_TYPE_IPFORWARD, NULL); - } else { - fwd_tag = NULL; + /* + * The tail loss probe recovered the last packet and + * we need to adjust the congestion window to take + * this loss into account. + */ + ++tcpstat.tcps_tlp_recoverlastpkt; + if (!IN_FASTRECOVERY(tp)) { + tcp_reduce_congestion_window(tp); + EXIT_FASTRECOVERY(tp); + } + tcp_ccdbg_trace(tp, th, TCP_CC_TLP_RECOVER_LASTPACKET); + } else if (tcp_rxtseg_detect_bad_rexmt(tp, th->th_ack)) { + /* + * All of the retransmitted segments were duplicated, this + * can be an indication of bad fast retransmit. + */ + tcpstat.tcps_dsack_badrexmt++; + tcp_bad_rexmt_restore_state(tp, th); + tcp_ccdbg_trace(tp, th, TCP_CC_DSACK_BAD_REXMT); + tcp_rxtseg_clean(tp); } - if (fwd_tag != NULL) { - struct ip_fwd_tag *ipfwd_tag = - (struct ip_fwd_tag *)(fwd_tag+1); +out: + tp->t_flagsext &= ~(TF_SENT_TLPROBE); + tp->t_tlphighrxt = 0; + tp->t_tlpstart = 0; - next_hop = ipfwd_tag->next_hop; - m_tag_delete(m, fwd_tag); + /* + * check if the latest ack was for a segment sent during PMTU + * blackhole detection. If the timestamp on the ack is before + * PMTU blackhole detection, then revert the size of the max + * segment to previous size. + */ + if (tp->t_rxtshift > 0 && (tp->t_flags & TF_BLACKHOLE) && + tp->t_pmtud_start_ts > 0 && TSTMP_SUPPORTED(tp)) { + if ((to->to_flags & TOF_TS) && to->to_tsecr != 0 + && TSTMP_LT(to->to_tsecr, tp->t_pmtud_start_ts)) { + tcp_pmtud_revert_segment_size(tp); + } } + if (tp->t_pmtud_start_ts > 0) { + tp->t_pmtud_start_ts = 0; + } +} -#if INET6 - struct ip6_hdr *ip6 = NULL; - int isipv6; -#endif /* INET6 */ - int rstreason; /* For badport_bandlim accounting purposes */ - struct proc *proc0=current_proc(); - - KERNEL_DEBUG(DBG_FNC_TCP_INPUT | DBG_FUNC_START,0,0,0,0,0); - -#if INET6 +/* + * Check if early retransmit can be attempted according to RFC 5827. + * + * If packet reordering is detected on a connection, fast recovery will + * be delayed until it is clear that the packet was lost and not reordered. + * But reordering detection is done only when SACK is enabled. + * + * On connections that do not support SACK, there is a limit on the number + * of early retransmits that can be done per minute. This limit is needed + * to make sure that too many packets are not retransmitted when there is + * packet reordering. + */ +static void +tcp_early_rexmt_check(struct tcpcb *tp, struct tcphdr *th) +{ + u_int32_t obytes, snd_off; + int32_t snd_len; + struct socket *so = tp->t_inpcb->inp_socket; + + if (early_rexmt && (SACK_ENABLED(tp) || + tp->t_early_rexmt_count < TCP_EARLY_REXMT_LIMIT) && + SEQ_GT(tp->snd_max, tp->snd_una) && + (tp->t_dupacks == 1 || + (SACK_ENABLED(tp) && + !TAILQ_EMPTY(&tp->snd_holes)))) { + /* + * If there are only a few outstanding + * segments on the connection, we might need + * to lower the retransmit threshold. This + * will allow us to do Early Retransmit as + * described in RFC 5827. + */ + if (SACK_ENABLED(tp) && + !TAILQ_EMPTY(&tp->snd_holes)) { + obytes = (tp->snd_max - tp->snd_fack) + + tp->sackhint.sack_bytes_rexmit; + } else { + obytes = (tp->snd_max - tp->snd_una); + } + + /* + * In order to lower retransmit threshold the + * following two conditions must be met. + * 1. the amount of outstanding data is less + * than 4*SMSS bytes + * 2. there is no unsent data ready for + * transmission or the advertised window + * will limit sending new segments. + */ + snd_off = tp->snd_max - tp->snd_una; + snd_len = min(so->so_snd.sb_cc, tp->snd_wnd) - snd_off; + if (obytes < (tp->t_maxseg << 2) && + snd_len <= 0) { + u_int32_t osegs; + + osegs = obytes / tp->t_maxseg; + if ((osegs * tp->t_maxseg) < obytes) { + osegs++; + } + + /* + * Since the connection might have already + * received some dupacks, we add them to + * to the outstanding segments count to get + * the correct retransmit threshold. + * + * By checking for early retransmit after + * receiving some duplicate acks when SACK + * is supported, the connection will + * enter fast recovery even if multiple + * segments are lost in the same window. + */ + osegs += tp->t_dupacks; + if (osegs < 4) { + tp->t_rexmtthresh = + ((osegs - 1) > 1) ? (osegs - 1) : 1; + tp->t_rexmtthresh = + min(tp->t_rexmtthresh, tcprexmtthresh); + tp->t_rexmtthresh = + max(tp->t_rexmtthresh, tp->t_dupacks); + + if (tp->t_early_rexmt_count == 0) { + tp->t_early_rexmt_win = tcp_now; + } + + if (tp->t_flagsext & TF_SENT_TLPROBE) { + tcpstat.tcps_tlp_recovery++; + tcp_ccdbg_trace(tp, th, + TCP_CC_TLP_RECOVERY); + } else { + tcpstat.tcps_early_rexmt++; + tp->t_early_rexmt_count++; + tcp_ccdbg_trace(tp, th, + TCP_CC_EARLY_RETRANSMIT); + } + } + } + } + + /* + * If we ever sent a TLP probe, the acknowledgement will trigger + * early retransmit because the value of snd_fack will be close + * to snd_max. This will take care of adjustments to the + * congestion window. So we can reset TF_SENT_PROBE flag. + */ + tp->t_flagsext &= ~(TF_SENT_TLPROBE); + tp->t_tlphighrxt = 0; + tp->t_tlpstart = 0; +} + +static boolean_t +tcp_tfo_syn(struct tcpcb *tp, struct tcpopt *to) +{ + u_char out[CCAES_BLOCK_SIZE]; + unsigned char len; + + if (!(to->to_flags & (TOF_TFO | TOF_TFOREQ)) || + !(tcp_fastopen & TCP_FASTOPEN_SERVER)) { + return FALSE; + } + + if ((to->to_flags & TOF_TFOREQ)) { + tp->t_tfo_flags |= TFO_F_OFFER_COOKIE; + + tp->t_tfo_stats |= TFO_S_COOKIEREQ_RECV; + tcpstat.tcps_tfo_cookie_req_rcv++; + return FALSE; + } + + /* Ok, then it must be an offered cookie. We need to check that ... */ + tcp_tfo_gen_cookie(tp->t_inpcb, out, sizeof(out)); + + len = *to->to_tfo - TCPOLEN_FASTOPEN_REQ; + to->to_tfo++; + if (memcmp(out, to->to_tfo, len)) { + /* Cookies are different! Let's return and offer a new cookie */ + tp->t_tfo_flags |= TFO_F_OFFER_COOKIE; + + tp->t_tfo_stats |= TFO_S_COOKIE_INVALID; + tcpstat.tcps_tfo_cookie_invalid++; + return FALSE; + } + + if (OSIncrementAtomic(&tcp_tfo_halfcnt) >= tcp_tfo_backlog) { + /* Need to decrement again as we just increased it... */ + OSDecrementAtomic(&tcp_tfo_halfcnt); + return FALSE; + } + + tp->t_tfo_flags |= TFO_F_COOKIE_VALID; + + tp->t_tfo_stats |= TFO_S_SYNDATA_RCV; + tcpstat.tcps_tfo_syn_data_rcv++; + + return TRUE; +} + +static void +tcp_tfo_synack(struct tcpcb *tp, struct tcpopt *to) +{ + if (to->to_flags & TOF_TFO) { + unsigned char len = *to->to_tfo - TCPOLEN_FASTOPEN_REQ; + + /* + * If this happens, things have gone terribly wrong. len should + * have been checked in tcp_dooptions. + */ + VERIFY(len <= TFO_COOKIE_LEN_MAX); + + to->to_tfo++; + + tcp_cache_set_cookie(tp, to->to_tfo, len); + tcp_heuristic_tfo_success(tp); + + tp->t_tfo_stats |= TFO_S_COOKIE_RCV; + tcpstat.tcps_tfo_cookie_rcv++; + if (tp->t_tfo_flags & TFO_F_COOKIE_SENT) { + tcpstat.tcps_tfo_cookie_wrong++; + tp->t_tfo_stats |= TFO_S_COOKIE_WRONG; + } + } else { + /* + * Thus, no cookie in the response, but we either asked for one + * or sent SYN+DATA. Now, we need to check whether we had to + * rexmit the SYN. If that's the case, it's better to start + * backing of TFO-cookie requests. + */ + if (!(tp->t_flagsext & TF_FASTOPEN_FORCE_ENABLE) && + tp->t_tfo_flags & TFO_F_SYN_LOSS) { + tp->t_tfo_stats |= TFO_S_SYN_LOSS; + tcpstat.tcps_tfo_syn_loss++; + + tcp_heuristic_tfo_loss(tp); + } else { + if (tp->t_tfo_flags & TFO_F_COOKIE_REQ) { + tp->t_tfo_stats |= TFO_S_NO_COOKIE_RCV; + tcpstat.tcps_tfo_no_cookie_rcv++; + } + + tcp_heuristic_tfo_success(tp); + } + } +} + +static void +tcp_tfo_rcv_probe(struct tcpcb *tp, int tlen) +{ + if (tlen != 0) { + return; + } + + tp->t_tfo_probe_state = TFO_PROBE_PROBING; + + /* + * We send the probe out rather quickly (after one RTO). It does not + * really hurt that much, it's only one additional segment on the wire. + */ + tp->t_timer[TCPT_KEEP] = OFFSET_FROM_START(tp, (TCP_REXMTVAL(tp))); +} + +static void +tcp_tfo_rcv_data(struct tcpcb *tp) +{ + /* Transition from PROBING to NONE as data has been received */ + if (tp->t_tfo_probe_state >= TFO_PROBE_PROBING) { + tp->t_tfo_probe_state = TFO_PROBE_NONE; + } +} + +static void +tcp_tfo_rcv_ack(struct tcpcb *tp, struct tcphdr *th) +{ + if (tp->t_tfo_probe_state == TFO_PROBE_PROBING && + tp->t_tfo_probes > 0) { + if (th->th_seq == tp->rcv_nxt) { + /* No hole, so stop probing */ + tp->t_tfo_probe_state = TFO_PROBE_NONE; + } else if (SEQ_GT(th->th_seq, tp->rcv_nxt)) { + /* There is a hole! Wait a bit for data... */ + tp->t_tfo_probe_state = TFO_PROBE_WAIT_DATA; + tp->t_timer[TCPT_KEEP] = OFFSET_FROM_START(tp, + TCP_REXMTVAL(tp)); + } + } +} + +/* + * Update snd_wnd information. + */ +static inline bool +tcp_update_window(struct tcpcb *tp, int thflags, struct tcphdr * th, + u_int32_t tiwin, int tlen) +{ + /* Don't look at the window if there is no ACK flag */ + if ((thflags & TH_ACK) && + (SEQ_LT(tp->snd_wl1, th->th_seq) || + (tp->snd_wl1 == th->th_seq && (SEQ_LT(tp->snd_wl2, th->th_ack) || + (tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd))))) { + /* keep track of pure window updates */ + if (tlen == 0 && + tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd) { + tcpstat.tcps_rcvwinupd++; + } + tp->snd_wnd = tiwin; + tp->snd_wl1 = th->th_seq; + tp->snd_wl2 = th->th_ack; + if (tp->snd_wnd > tp->max_sndwnd) { + tp->max_sndwnd = tp->snd_wnd; + } + + if (tp->t_inpcb->inp_socket->so_flags & SOF_MP_SUBFLOW) { + mptcp_update_window_wakeup(tp); + } + return true; + } + return false; +} + +static void +tcp_handle_wakeup(struct socket *so, int read_wakeup, int write_wakeup) +{ + if (read_wakeup != 0) { + sorwakeup(so); + } + if (write_wakeup != 0) { + sowwakeup(so); + } +} + +void +tcp_input(struct mbuf *m, int off0) +{ + struct tcphdr *th; + struct ip *ip = NULL; + struct inpcb *inp; + u_char *optp = NULL; + int optlen = 0; + int tlen, off; + int drop_hdrlen; + struct tcpcb *tp = 0; + int thflags; + struct socket *so = 0; + int todrop, acked, ourfinisacked, needoutput = 0; + int read_wakeup = 0; + int write_wakeup = 0; + struct in_addr laddr; +#if INET6 + struct in6_addr laddr6; +#endif + int dropsocket = 0; + int iss = 0, nosock = 0; + u_int32_t tiwin, sack_bytes_acked = 0; + struct tcpopt to; /* options in this segment */ +#if TCPDEBUG + short ostate = 0; +#endif +#if IPFIREWALL + struct sockaddr_in *next_hop = NULL; + struct m_tag *fwd_tag; +#endif /* IPFIREWALL */ + u_char ip_ecn = IPTOS_ECN_NOTECT; + unsigned int ifscope; + uint8_t isconnected, isdisconnected; + struct ifnet *ifp = m->m_pkthdr.rcvif; + int pktf_sw_lro_pkt = (m->m_pkthdr.pkt_flags & PKTF_SW_LRO_PKT) ? 1 : 0; + int nlropkts = (pktf_sw_lro_pkt == 1) ? m->m_pkthdr.lro_npkts : 1; + int turnoff_lro = 0, win; +#if MPTCP + struct mptcb *mp_tp = NULL; +#endif /* MPTCP */ + boolean_t cell = IFNET_IS_CELLULAR(ifp); + boolean_t wifi = (!cell && IFNET_IS_WIFI(ifp)); + boolean_t wired = (!wifi && IFNET_IS_WIRED(ifp)); + boolean_t recvd_dsack = FALSE; + struct tcp_respond_args tra; + int prev_t_state; + boolean_t check_cfil = cfil_filter_present(); + bool findpcb_iterated = false; + /* + * The mbuf may be freed after it has been added to the receive socket + * buffer or the reassembly queue, so we reinitialize th to point to a + * safe copy of the TCP header + */ + struct tcphdr saved_tcphdr = {}; + /* + * Save copy of the IPv4/IPv6 header. + * Note: use array of uint32_t to silence compiler warning when casting + * to a struct ip6_hdr pointer. + */ +#define MAX_IPWORDS ((sizeof(struct ip) + MAX_IPOPTLEN) / sizeof(uint32_t)) + uint32_t saved_hdr[MAX_IPWORDS]; + +#define TCP_INC_VAR(stat, npkts) do { \ + stat += npkts; \ +} while (0) + + TCP_INC_VAR(tcpstat.tcps_rcvtotal, nlropkts); +#if IPFIREWALL + /* Grab info from PACKET_TAG_IPFORWARD tag prepended to the chain. */ + if (!SLIST_EMPTY(&m->m_pkthdr.tags)) { + fwd_tag = m_tag_locate(m, KERNEL_MODULE_TAG_ID, + KERNEL_TAG_TYPE_IPFORWARD, NULL); + } else { + fwd_tag = NULL; + } + if (fwd_tag != NULL) { + struct ip_fwd_tag *ipfwd_tag = + (struct ip_fwd_tag *)(fwd_tag + 1); + + next_hop = ipfwd_tag->next_hop; + m_tag_delete(m, fwd_tag); + } +#endif /* IPFIREWALL */ + +#if INET6 + struct ip6_hdr *ip6 = NULL; + int isipv6; +#endif /* INET6 */ + int rstreason; /* For badport_bandlim accounting purposes */ + struct proc *proc0 = current_proc(); + + KERNEL_DEBUG(DBG_FNC_TCP_INPUT | DBG_FUNC_START, 0, 0, 0, 0, 0); + +#if INET6 isipv6 = (mtod(m, struct ip *)->ip_v == 6) ? 1 : 0; #endif bzero((char *)&to, sizeof(to)); #if INET6 if (isipv6) { - /* - * Expect 32-bit aligned data pointer on - * strict-align platforms + /* + * Expect 32-bit aligned data pointer on + * strict-align platforms */ MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m); @@ -1406,12 +2024,14 @@ tcp_input(m, off0) tlen = sizeof(*ip6) + ntohs(ip6->ip6_plen) - off0; th = (struct tcphdr *)(void *)((caddr_t)ip6 + off0); - if (tcp_input_checksum(AF_INET6, m, th, off0, tlen)) + if (tcp_input_checksum(AF_INET6, m, th, off0, tlen)) { + TCP_LOG_DROP_PKT(ip6, th, ifp, "IPv6 bad tcp checksum"); goto dropnosock; + } KERNEL_DEBUG(DBG_LAYER_BEG, ((th->th_dport << 16) | th->th_sport), - (((ip6->ip6_src.s6_addr16[0]) << 16) | (ip6->ip6_dst.s6_addr16[0])), - th->th_seq, th->th_ack, th->th_win); + (((ip6->ip6_src.s6_addr16[0]) << 16) | (ip6->ip6_dst.s6_addr16[0])), + th->th_seq, th->th_ack, th->th_win); /* * Be proactive about unspecified IPv6 address in source. * As we use all-zero to indicate unbounded/unconnected pcb, @@ -1423,78 +2043,83 @@ tcp_input(m, off0) if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)) { /* XXX stat */ IF_TCP_STATINC(ifp, unspecv6); + TCP_LOG_DROP_PKT(ip6, th, ifp, "src IPv6 address unspecified"); goto dropnosock; } DTRACE_TCP5(receive, struct mbuf *, m, struct inpcb *, NULL, - struct ip6_hdr *, ip6, struct tcpcb *, NULL, - struct tcphdr *, th); + struct ip6_hdr *, ip6, struct tcpcb *, NULL, + struct tcphdr *, th); ip_ecn = (ntohl(ip6->ip6_flow) >> 20) & IPTOS_ECN_MASK; } else #endif /* INET6 */ { - /* - * Get IP and TCP header together in first mbuf. - * Note: IP leaves IP header in first mbuf. - */ - if (off0 > sizeof (struct ip)) { - ip_stripoptions(m, (struct mbuf *)0); - off0 = sizeof(struct ip); - } - if (m->m_len < sizeof (struct tcpiphdr)) { - if ((m = m_pullup(m, sizeof (struct tcpiphdr))) == 0) { - tcpstat.tcps_rcvshort++; - return; + /* + * Get IP and TCP header together in first mbuf. + * Note: IP leaves IP header in first mbuf. + */ + if (off0 > sizeof(struct ip)) { + ip_stripoptions(m); + off0 = sizeof(struct ip); + } + if (m->m_len < sizeof(struct tcpiphdr)) { + if ((m = m_pullup(m, sizeof(struct tcpiphdr))) == 0) { + tcpstat.tcps_rcvshort++; + return; + } } - } - /* Expect 32-bit aligned data pointer on strict-align platforms */ - MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m); + /* Expect 32-bit aligned data pointer on strict-align platforms */ + MBUF_STRICT_DATA_ALIGNMENT_CHECK_32(m); - ip = mtod(m, struct ip *); - th = (struct tcphdr *)(void *)((caddr_t)ip + off0); - tlen = ip->ip_len; + ip = mtod(m, struct ip *); + th = (struct tcphdr *)(void *)((caddr_t)ip + off0); + tlen = ip->ip_len; - if (tcp_input_checksum(AF_INET, m, th, off0, tlen)) - goto dropnosock; + if (tcp_input_checksum(AF_INET, m, th, off0, tlen)) { + TCP_LOG_DROP_PKT(ip, th, ifp, "IPv4 bad tcp checksum"); + goto dropnosock; + } #if INET6 - /* Re-initialization for later version check */ - ip->ip_v = IPVERSION; + /* Re-initialization for later version check */ + ip->ip_v = IPVERSION; #endif - ip_ecn = (ip->ip_tos & IPTOS_ECN_MASK); - - DTRACE_TCP5(receive, struct mbuf *, m, struct inpcb *, NULL, - struct ip *, ip, struct tcpcb *, NULL, struct tcphdr *, th); + ip_ecn = (ip->ip_tos & IPTOS_ECN_MASK); - KERNEL_DEBUG(DBG_LAYER_BEG, ((th->th_dport << 16) | th->th_sport), - (((ip->ip_src.s_addr & 0xffff) << 16) | (ip->ip_dst.s_addr & 0xffff)), - th->th_seq, th->th_ack, th->th_win); + DTRACE_TCP5(receive, struct mbuf *, m, struct inpcb *, NULL, + struct ip *, ip, struct tcpcb *, NULL, struct tcphdr *, th); + KERNEL_DEBUG(DBG_LAYER_BEG, ((th->th_dport << 16) | th->th_sport), + (((ip->ip_src.s_addr & 0xffff) << 16) | (ip->ip_dst.s_addr & 0xffff)), + th->th_seq, th->th_ack, th->th_win); } +#define TCP_LOG_HDR (isipv6 ? (void *)ip6 : (void *)ip) + /* * Check that TCP offset makes sense, - * pull out TCP options and adjust length. XXX + * pull out TCP options and adjust length. */ off = th->th_off << 2; - if (off < sizeof (struct tcphdr) || off > tlen) { + if (off < sizeof(struct tcphdr) || off > tlen) { tcpstat.tcps_rcvbadoff++; IF_TCP_STATINC(ifp, badformat); + TCP_LOG_DROP_PKT(TCP_LOG_HDR, th, ifp, "bad tcp offset"); goto dropnosock; } - tlen -= off; /* tlen is used instead of ti->ti_len */ - if (off > sizeof (struct tcphdr)) { + tlen -= off; /* tlen is used instead of ti->ti_len */ + if (off > sizeof(struct tcphdr)) { #if INET6 if (isipv6) { - IP6_EXTHDR_CHECK(m, off0, off, return); + IP6_EXTHDR_CHECK(m, off0, off, return ); ip6 = mtod(m, struct ip6_hdr *); th = (struct tcphdr *)(void *)((caddr_t)ip6 + off0); } else #endif /* INET6 */ { if (m->m_len < sizeof(struct ip) + off) { - if ((m = m_pullup(m, sizeof (struct ip) + off)) == 0) { + if ((m = m_pullup(m, sizeof(struct ip) + off)) == 0) { tcpstat.tcps_rcvshort++; return; } @@ -1502,9 +2127,9 @@ tcp_input(m, off0) th = (struct tcphdr *)(void *)((caddr_t)ip + off0); } } - optlen = off - sizeof (struct tcphdr); + optlen = off - sizeof(struct tcphdr); optp = (u_char *)(th + 1); - /* + /* * Do quick retrieval of timestamp options ("options * prediction?"). If timestamp is the only option and it's * formatted as recommended in RFC 1323 appendix A, we @@ -1512,14 +2137,14 @@ tcp_input(m, off0) * tcp_dooptions(), etc. */ if ((optlen == TCPOLEN_TSTAMP_APPA || - (optlen > TCPOLEN_TSTAMP_APPA && - optp[TCPOLEN_TSTAMP_APPA] == TCPOPT_EOL)) && - *(u_int32_t *)(void *)optp == htonl(TCPOPT_TSTAMP_HDR) && - (th->th_flags & TH_SYN) == 0) { + (optlen > TCPOLEN_TSTAMP_APPA && + optp[TCPOLEN_TSTAMP_APPA] == TCPOPT_EOL)) && + *(u_int32_t *)(void *)optp == htonl(TCPOPT_TSTAMP_HDR) && + (th->th_flags & TH_SYN) == 0) { to.to_flags |= TOF_TS; to.to_tsval = ntohl(*(u_int32_t *)(void *)(optp + 4)); to.to_tsecr = ntohl(*(u_int32_t *)(void *)(optp + 8)); - optp = NULL; /* we've parsed the options */ + optp = NULL; /* we've parsed the options */ } } thflags = th->th_flags; @@ -1532,8 +2157,9 @@ tcp_input(m, off0) * * This is a violation of the TCP specification. */ - if (drop_synfin && (thflags & (TH_SYN|TH_FIN)) == (TH_SYN|TH_FIN)) { + if (drop_synfin && (thflags & (TH_SYN | TH_FIN)) == (TH_SYN | TH_FIN)) { IF_TCP_STATINC(ifp, synfin); + TCP_LOG_DROP_PKT(TCP_LOG_HDR, th, ifp, "drop SYN FIN"); goto dropnosock; } #endif @@ -1547,7 +2173,7 @@ tcp_input(m, off0) * parameters to be unchanged. */ drop_hdrlen = off0 + off; - + /* Since this is an entry point for input processing of tcp packets, we * can update the tcp clock here. */ @@ -1560,20 +2186,21 @@ tcp_input(m, off0) * absence of a PCB, when scoped routing (and thus source interface * selection) are enabled. */ - if ((m->m_pkthdr.pkt_flags & PKTF_LOOP) || m->m_pkthdr.rcvif == NULL) + if ((m->m_pkthdr.pkt_flags & PKTF_LOOP) || m->m_pkthdr.rcvif == NULL) { ifscope = IFSCOPE_NONE; - else + } else { ifscope = m->m_pkthdr.rcvif->if_index; + } - /* - * Convert TCP protocol specific fields to host format. - */ + /* + * Convert TCP protocol specific fields to host format. + */ #if BYTE_ORDER != BIG_ENDIAN - NTOHL(th->th_seq); - NTOHL(th->th_ack); - NTOHS(th->th_win); - NTOHS(th->th_urp); + NTOHL(th->th_seq); + NTOHL(th->th_ack); + NTOHS(th->th_win); + NTOHS(th->th_urp); #endif /* @@ -1592,12 +2219,12 @@ findpcb: ) { /* * Diverted. Pretend to be the destination. - * already got one like this? + * already got one like this? */ inp = in_pcblookup_hash(&tcbinfo, ip->ip_src, th->th_sport, - ip->ip_dst, th->th_dport, 0, m->m_pkthdr.rcvif); + ip->ip_dst, th->th_dport, 0, m->m_pkthdr.rcvif); if (!inp) { - /* + /* * No, then it's new. Try find the ambushing socket */ if (!next_hop->sin_port) { @@ -1607,24 +2234,24 @@ findpcb: } else { inp = in_pcblookup_hash(&tcbinfo, ip->ip_src, th->th_sport, - next_hop->sin_addr, + next_hop->sin_addr, ntohs(next_hop->sin_port), 1, m->m_pkthdr.rcvif); } } } else -#endif /* IPFIREWALL_FORWARD */ - { +#endif /* IPFIREWALL_FORWARD */ + { #if INET6 - if (isipv6) - inp = in6_pcblookup_hash(&tcbinfo, &ip6->ip6_src, th->th_sport, - &ip6->ip6_dst, th->th_dport, 1, - m->m_pkthdr.rcvif); - else + if (isipv6) { + inp = in6_pcblookup_hash(&tcbinfo, &ip6->ip6_src, th->th_sport, + &ip6->ip6_dst, th->th_dport, 1, + m->m_pkthdr.rcvif); + } else #endif /* INET6 */ - inp = in_pcblookup_hash(&tcbinfo, ip->ip_src, th->th_sport, - ip->ip_dst, th->th_dport, 1, m->m_pkthdr.rcvif); - } + inp = in_pcblookup_hash(&tcbinfo, ip->ip_src, th->th_sport, + ip->ip_dst, th->th_dport, 1, m->m_pkthdr.rcvif); + } /* * Use the interface scope information from the PCB for outbound @@ -1632,42 +2259,9 @@ findpcb: * enabled, tcp_respond will use the scope of the interface where * the segment arrived on. */ - if (inp != NULL && (inp->inp_flags & INP_BOUND_IF)) + if (inp != NULL && (inp->inp_flags & INP_BOUND_IF)) { ifscope = inp->inp_boundifp->if_index; - - /* - * If the PCB is present and the socket isn't allowed to use - * the cellular interface, indicate it as such for tcp_respond. - */ - if (inp != NULL && (inp->inp_flags & INP_NO_IFT_CELLULAR)) - nocell = 1; - -#if IPSEC - if (ipsec_bypass == 0) { -#if INET6 - if (isipv6) { - if (inp != NULL && ipsec6_in_reject_so(m, inp->inp_socket)) { - IPSEC_STAT_INCREMENT(ipsec6stat.in_polvio); - if (in_pcb_checkstate(inp, WNT_RELEASE, 0) == WNT_STOPUSING) - inp = NULL; // pretend we didn't find it - - IF_TCP_STATINC(ifp, badformatipsec); - - goto dropnosock; - } - } else -#endif /* INET6 */ - if (inp != NULL && ipsec4_in_reject_so(m, inp->inp_socket)) { - IPSEC_STAT_INCREMENT(ipsecstat.in_polvio); - if (in_pcb_checkstate(inp, WNT_RELEASE, 0) == WNT_STOPUSING) - inp = NULL; // pretend we didn't find it - - IF_TCP_STATINC(ifp, badformatipsec); - - goto dropnosock; - } } -#endif /*IPSEC*/ /* * If the state is CLOSED (i.e., TCB does not exist) then @@ -1695,56 +2289,63 @@ findpcb: } switch (log_in_vain) { case 1: - if(thflags & TH_SYN) + if (thflags & TH_SYN) { log(LOG_INFO, - "Connection attempt to TCP %s:%d from %s:%d\n", - dbuf, ntohs(th->th_dport), - sbuf, - ntohs(th->th_sport)); + "Connection attempt to TCP %s:%d from %s:%d\n", + dbuf, ntohs(th->th_dport), + sbuf, + ntohs(th->th_sport)); + } break; case 2: log(LOG_INFO, - "Connection attempt to TCP %s:%d from %s:%d flags:0x%x\n", - dbuf, ntohs(th->th_dport), sbuf, - ntohs(th->th_sport), thflags); + "Connection attempt to TCP %s:%d from %s:%d flags:0x%x\n", + dbuf, ntohs(th->th_dport), sbuf, + ntohs(th->th_sport), thflags); break; case 3: case 4: if ((thflags & TH_SYN) && !(thflags & TH_ACK) && - !(m->m_flags & (M_BCAST | M_MCAST)) && + !(m->m_flags & (M_BCAST | M_MCAST)) && #if INET6 - ((isipv6 && !IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &ip6->ip6_src)) || - (!isipv6 && ip->ip_dst.s_addr != ip->ip_src.s_addr)) + ((isipv6 && !IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, &ip6->ip6_src)) || + (!isipv6 && ip->ip_dst.s_addr != ip->ip_src.s_addr)) #else - ip->ip_dst.s_addr != ip->ip_src.s_addr + ip->ip_dst.s_addr != ip->ip_src.s_addr #endif - ) + ) { log_in_vain_log((LOG_INFO, - "Stealth Mode connection attempt to TCP %s:%d from %s:%d\n", - dbuf, ntohs(th->th_dport), - sbuf, - ntohs(th->th_sport))); + "Stealth Mode connection attempt to TCP %s:%d from %s:%d\n", + dbuf, ntohs(th->th_dport), + sbuf, + ntohs(th->th_sport))); + } break; default: break; } } - if (blackhole) { - if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_type != IFT_LOOP) - + if (blackhole) { + if (m->m_pkthdr.rcvif && m->m_pkthdr.rcvif->if_type != IFT_LOOP) { switch (blackhole) { case 1: - if (thflags & TH_SYN) + if (thflags & TH_SYN) { + TCP_LOG_DROP_PKT(TCP_LOG_HDR, th, ifp, "blackhole 1 syn for closed port"); goto dropnosock; + } break; case 2: + TCP_LOG_DROP_PKT(TCP_LOG_HDR, th, ifp, "blackhole 2 closed port"); goto dropnosock; default: + TCP_LOG_DROP_PKT(TCP_LOG_HDR, th, ifp, "blackhole closed port"); goto dropnosock; } + } } rstreason = BANDLIM_RST_CLOSEDPORT; IF_TCP_STATINC(ifp, noconnnolist); + TCP_LOG_DROP_PKT(TCP_LOG_HDR, th, ifp, "closed port"); goto dropwithresetnosock; } so = inp->inp_socket; @@ -1758,73 +2359,186 @@ findpcb: #if TEMPDEBUG printf("tcp_input: no more socket for inp=%x. This shouldn't happen\n", inp); #endif + TCP_LOG_DROP_PKT(TCP_LOG_HDR, th, ifp, "inp_socket NULL"); goto dropnosock; } - tcp_lock(so, 1, 0); + socket_lock(so, 1); if (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING) { - tcp_unlock(so, 1, (void *)2); - inp = NULL; // pretend we didn't find it + socket_unlock(so, 1); + inp = NULL; // pretend we didn't find it + TCP_LOG_DROP_PKT(TCP_LOG_HDR, th, ifp, "inp state WNT_STOPUSING"); goto dropnosock; } + if (!isipv6 && inp->inp_faddr.s_addr != INADDR_ANY) { + if (inp->inp_faddr.s_addr != ip->ip_src.s_addr || + inp->inp_laddr.s_addr != ip->ip_dst.s_addr || + inp->inp_fport != th->th_sport || + inp->inp_lport != th->th_dport) { + os_log_error(OS_LOG_DEFAULT, "%s 5-tuple does not match: %u:%u %u:%u\n", + __func__, + ntohs(inp->inp_fport), ntohs(th->th_sport), + ntohs(inp->inp_lport), ntohs(th->th_dport)); + if (findpcb_iterated) { + goto drop; + } + findpcb_iterated = true; + socket_unlock(so, 1); + inp = NULL; + goto findpcb; + } + } else if (isipv6 && !IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) { + if (!IN6_ARE_ADDR_EQUAL(&inp->in6p_faddr, &ip6->ip6_src) || + !IN6_ARE_ADDR_EQUAL(&inp->in6p_laddr, &ip6->ip6_dst) || + inp->inp_fport != th->th_sport || + inp->inp_lport != th->th_dport) { + os_log_error(OS_LOG_DEFAULT, "%s 5-tuple does not match: %u:%u %u:%u\n", + __func__, + ntohs(inp->inp_fport), ntohs(th->th_sport), + ntohs(inp->inp_lport), ntohs(th->th_dport)); + if (findpcb_iterated) { + goto drop; + } + findpcb_iterated = true; + socket_unlock(so, 1); + inp = NULL; + goto findpcb; + } + } + tp = intotcpcb(inp); - if (tp == 0) { + if (tp == NULL) { rstreason = BANDLIM_RST_CLOSEDPORT; IF_TCP_STATINC(ifp, noconnlist); + TCP_LOG_DROP_PKT(TCP_LOG_HDR, th, ifp, "tp is NULL"); goto dropwithreset; } - if (tp->t_state == TCPS_CLOSED) + + TCP_LOG_TH_FLAGS(TCP_LOG_HDR, th, tp, false, ifp); + + if (tp->t_state == TCPS_CLOSED) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "tp state TCPS_CLOSED"); + goto drop; + } + +#if NECP + if (so->so_state & SS_ISCONNECTED) { + // Connected TCP sockets have a fully-bound local and remote, + // so the policy check doesn't need to override addresses + if (!necp_socket_is_allowed_to_send_recv(inp, ifp, NULL, NULL, NULL)) { + TCP_LOG_DROP_NECP(TCP_LOG_HDR, th, intotcpcb(inp), false); + IF_TCP_STATINC(ifp, badformat); + goto drop; + } + } else { + /* + * If the proc_uuid_policy table has been updated since the last use + * of the listening socket (i.e., the proc_uuid_policy_table_gencount + * has been updated), the flags in the socket may be out of date. + * If INP2_WANT_APP_POLICY is stale, inbound packets may + * be dropped by NECP if the socket should now match a per-app + * exception policy. + * In order to avoid this refresh the proc_uuid_policy state to + * potentially recalculate the socket's flags before checking + * with NECP. + */ + (void) inp_update_policy(inp); +#if INET6 + if (isipv6) { + if (!necp_socket_is_allowed_to_send_recv_v6(inp, + th->th_dport, th->th_sport, &ip6->ip6_dst, + &ip6->ip6_src, ifp, NULL, NULL, NULL)) { + TCP_LOG_DROP_NECP(TCP_LOG_HDR, th, intotcpcb(inp), false); + IF_TCP_STATINC(ifp, badformat); + goto drop; + } + } else +#endif + { + if (!necp_socket_is_allowed_to_send_recv_v4(inp, + th->th_dport, th->th_sport, &ip->ip_dst, &ip->ip_src, + ifp, NULL, NULL, NULL)) { + TCP_LOG_DROP_NECP(TCP_LOG_HDR, th, intotcpcb(inp), false); + IF_TCP_STATINC(ifp, badformat); + goto drop; + } + } + } +#endif /* NECP */ + + prev_t_state = tp->t_state; + + /* If none of the FIN|SYN|RST|ACK flag is set, drop */ + if (tcp_do_rfc5961 && (thflags & TH_ACCEPT) == 0) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "rfc5961 TH_ACCEPT == 0"); goto drop; + } /* Unscale the window into a 32-bit value. */ - if ((thflags & TH_SYN) == 0) + if ((thflags & TH_SYN) == 0) { tiwin = th->th_win << tp->snd_scale; - else + } else { tiwin = th->th_win; + } + #if CONFIG_MACF_NET - if (mac_inpcb_check_deliver(inp, m, AF_INET, SOCK_STREAM)) + if (mac_inpcb_check_deliver(inp, m, AF_INET, SOCK_STREAM)) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "mac_inpcb_check_deliver failed"); goto drop; + } #endif /* Avoid processing packets while closing a listen socket */ - if (tp->t_state == TCPS_LISTEN && - (so->so_options & SO_ACCEPTCONN) == 0) + if (tp->t_state == TCPS_LISTEN && + (so->so_options & SO_ACCEPTCONN) == 0) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "closing a listening socket"); goto drop; + } - if (so->so_options & (SO_DEBUG|SO_ACCEPTCONN)) { + if (so->so_options & (SO_DEBUG | SO_ACCEPTCONN)) { #if TCPDEBUG if (so->so_options & SO_DEBUG) { ostate = tp->t_state; #if INET6 - if (isipv6) + if (isipv6) { bcopy((char *)ip6, (char *)tcp_saveipgen, - sizeof(*ip6)); - else + sizeof(*ip6)); + } else #endif /* INET6 */ bcopy((char *)ip, (char *)tcp_saveipgen, sizeof(*ip)); tcp_savetcp = *th; } #endif if (so->so_options & SO_ACCEPTCONN) { - register struct tcpcb *tp0 = tp; + struct tcpcb *tp0 = tp; struct socket *so2; struct socket *oso; struct sockaddr_storage from; + struct sockaddr_storage to2; #if INET6 struct inpcb *oinp = sotoinpcb(so); #endif /* INET6 */ struct ifnet *head_ifscope; - unsigned int head_nocell, head_recvanyif; + unsigned int head_nocell, head_recvanyif, + head_noexpensive, head_awdl_unrestricted, + head_intcoproc_allowed, head_external_port, + head_noconstrained; /* Get listener's bound-to-interface, if any */ head_ifscope = (inp->inp_flags & INP_BOUND_IF) ? inp->inp_boundifp : NULL; /* Get listener's no-cellular information, if any */ - head_nocell = (inp->inp_flags & INP_NO_IFT_CELLULAR) ? 1 : 0; + head_nocell = INP_NO_CELLULAR(inp); /* Get listener's recv-any-interface, if any */ head_recvanyif = (inp->inp_flags & INP_RECV_ANYIF); + /* Get listener's no-expensive information, if any */ + head_noexpensive = INP_NO_EXPENSIVE(inp); + head_noconstrained = INP_NO_CONSTRAINED(inp); + head_awdl_unrestricted = INP_AWDL_UNRESTRICTED(inp); + head_intcoproc_allowed = INP_INTCOPROC_ALLOWED(inp); + head_external_port = (inp->inp_flags2 & INP2_EXTERNAL_PORT); /* * If the state is LISTEN then ignore segment if it contains an RST. @@ -1832,13 +2546,15 @@ findpcb: * If it does not contain a SYN then it is not interesting; drop it. * If it is from this socket, drop it, it must be forged. */ - if ((thflags & (TH_RST|TH_ACK|TH_SYN)) != TH_SYN) { + if ((thflags & (TH_RST | TH_ACK | TH_SYN)) != TH_SYN) { IF_TCP_STATINC(ifp, listbadsyn); if (thflags & TH_RST) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "SYN with RST"); goto drop; } if (thflags & TH_ACK) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "SYN with ACK"); tp = NULL; tcpstat.tcps_badsyn++; rstreason = BANDLIM_RST_OPENPORT; @@ -1847,19 +2563,24 @@ findpcb: /* We come here if there is no SYN set */ tcpstat.tcps_badsyn++; + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "bad SYN"); goto drop; } - KERNEL_DEBUG(DBG_FNC_TCP_NEWCONN | DBG_FUNC_START,0,0,0,0,0); - if (th->th_dport == th->th_sport) { + KERNEL_DEBUG(DBG_FNC_TCP_NEWCONN | DBG_FUNC_START, 0, 0, 0, 0, 0); + if (th->th_dport == th->th_sport) { #if INET6 if (isipv6) { if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_dst, - &ip6->ip6_src)) + &ip6->ip6_src)) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "bad tuple same port"); goto drop; + } } else #endif /* INET6 */ - if (ip->ip_dst.s_addr == ip->ip_src.s_addr) - goto drop; + if (ip->ip_dst.s_addr == ip->ip_src.s_addr) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "bad tuple same IPv4 address"); + goto drop; + } } /* * RFC1122 4.2.3.10, p. 104: discard bcast/mcast SYN @@ -1869,20 +2590,26 @@ findpcb: * Packets with a multicast source address should also * be discarded. */ - if (m->m_flags & (M_BCAST|M_MCAST)) + if (m->m_flags & (M_BCAST | M_MCAST)) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "mbuf M_BCAST | M_MCAST"); goto drop; + } #if INET6 if (isipv6) { if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || - IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) + IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "IN6_IS_ADDR_MULTICAST"); goto drop; + } } else #endif if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || - IN_MULTICAST(ntohl(ip->ip_src.s_addr)) || - ip->ip_src.s_addr == htonl(INADDR_BROADCAST) || - in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) + IN_MULTICAST(ntohl(ip->ip_src.s_addr)) || + ip->ip_src.s_addr == htonl(INADDR_BROADCAST) || + in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "multicast or broadcast address"); goto drop; + } #if INET6 @@ -1910,33 +2637,52 @@ findpcb: tp = NULL; rstreason = BANDLIM_RST_OPENPORT; IF_TCP_STATINC(ifp, deprecate6); + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "deprecated IPv6 address"); goto dropwithreset; } } } #endif - if (so->so_filt) { + if (so->so_filt || check_cfil) { #if INET6 if (isipv6) { - struct sockaddr_in6 *sin6 = (struct sockaddr_in6*)&from; - + struct sockaddr_in6 *sin6 = (struct sockaddr_in6*)&from; + sin6->sin6_len = sizeof(*sin6); sin6->sin6_family = AF_INET6; sin6->sin6_port = th->th_sport; sin6->sin6_flowinfo = 0; sin6->sin6_addr = ip6->ip6_src; sin6->sin6_scope_id = 0; - } - else + + sin6 = (struct sockaddr_in6*)&to2; + + sin6->sin6_len = sizeof(struct sockaddr_in6); + sin6->sin6_family = AF_INET6; + sin6->sin6_port = th->th_dport; + sin6->sin6_flowinfo = 0; + sin6->sin6_addr = ip6->ip6_dst; + sin6->sin6_scope_id = 0; + } else #endif { struct sockaddr_in *sin = (struct sockaddr_in*)&from; - + sin->sin_len = sizeof(*sin); sin->sin_family = AF_INET; sin->sin_port = th->th_sport; sin->sin_addr = ip->ip_src; + + sin = (struct sockaddr_in*)&to2; + + sin->sin_len = sizeof(struct sockaddr_in); + sin->sin_family = AF_INET; + sin->sin_port = th->th_dport; + sin->sin_addr = ip->ip_dst; } + } + + if (so->so_filt) { so2 = sonewconn(so, 0, (struct sockaddr*)&from); } else { so2 = sonewconn(so, 0, NULL); @@ -1944,13 +2690,16 @@ findpcb: if (so2 == 0) { tcpstat.tcps_listendrop++; if (tcp_dropdropablreq(so)) { - if (so->so_filt) + if (so->so_filt) { so2 = sonewconn(so, 0, (struct sockaddr*)&from); - else + } else { so2 = sonewconn(so, 0, NULL); + } } - if (!so2) + if (!so2) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, " listen drop"); goto drop; + } } /* Point "inp" and "tp" in tandem to new socket */ @@ -1958,10 +2707,10 @@ findpcb: tp = intotcpcb(inp); oso = so; - tcp_unlock(so, 0, 0); /* Unlock but keep a reference on listener for now */ + socket_unlock(so, 0); /* Unlock but keep a reference on listener for now */ so = so2; - tcp_lock(so, 1, 0); + socket_lock(so, 1); /* * Mark socket as temporary until we're * committed to keeping it. The code at @@ -1987,28 +2736,45 @@ findpcb: inp->inp_flags &= ~INP_BOUND_IF; } /* - * Inherit INP_NO_IFT_CELLULAR from listener. + * Inherit restrictions from listener. */ if (head_nocell) { - inp->inp_flags |= INP_NO_IFT_CELLULAR; + inp_set_nocellular(inp); + } + if (head_noexpensive) { + inp_set_noexpensive(inp); + } + if (head_noconstrained) { + inp_set_noconstrained(inp); + } + if (head_awdl_unrestricted) { + inp_set_awdl_unrestricted(inp); + } + if (head_intcoproc_allowed) { + inp_set_intcoproc_allowed(inp); } /* * Inherit {IN,IN6}_RECV_ANYIF from listener. */ - if (head_recvanyif) + if (head_recvanyif) { inp->inp_flags |= INP_RECV_ANYIF; - else + } else { inp->inp_flags &= ~INP_RECV_ANYIF; + } + + if (head_external_port) { + inp->inp_flags2 |= INP2_EXTERNAL_PORT; + } #if INET6 - if (isipv6) + if (isipv6) { inp->in6p_laddr = ip6->ip6_dst; - else { + } else { inp->inp_vflag &= ~INP_IPV6; inp->inp_vflag |= INP_IPV4; #endif /* INET6 */ - inp->inp_laddr = ip->ip_dst; + inp->inp_laddr = ip->ip_dst; #if INET6 - } + } #endif /* INET6 */ inp->inp_lport = th->th_dport; if (in_pcbinshash(inp, 0) != 0) { @@ -2017,155 +2783,217 @@ findpcb: * put the PCB on the hash lists. */ #if INET6 - if (isipv6) + if (isipv6) { inp->in6p_laddr = in6addr_any; - else + } else #endif /* INET6 */ - inp->inp_laddr.s_addr = INADDR_ANY; + inp->inp_laddr.s_addr = INADDR_ANY; inp->inp_lport = 0; - tcp_lock(oso, 0, 0); /* release ref on parent */ - tcp_unlock(oso, 1, 0); + socket_lock(oso, 0); /* release ref on parent */ + socket_unlock(oso, 1); + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, " in_pcbinshash failed"); goto drop; } #if INET6 if (isipv6) { - /* - * Inherit socket options from the listening - * socket. - * Note that in6p_inputopts are not (even - * should not be) copied, since it stores + /* + * Inherit socket options from the listening + * socket. + * Note that in6p_inputopts are not (even + * should not be) copied, since it stores * previously received options and is used to - * detect if each new option is different than - * the previous one and hence should be passed - * to a user. - * If we copied in6p_inputopts, a user would - * not be able to receive options just after - * calling the accept system call. - */ + * detect if each new option is different than + * the previous one and hence should be passed + * to a user. + * If we copied in6p_inputopts, a user would + * not be able to receive options just after + * calling the accept system call. + */ inp->inp_flags |= - oinp->inp_flags & INP_CONTROLOPTS; - if (oinp->in6p_outputopts) - inp->in6p_outputopts = - ip6_copypktopts(oinp->in6p_outputopts, - M_NOWAIT); + oinp->inp_flags & INP_CONTROLOPTS; + if (oinp->in6p_outputopts) { + inp->in6p_outputopts = + ip6_copypktopts(oinp->in6p_outputopts, + M_NOWAIT); + } } else #endif /* INET6 */ + { inp->inp_options = ip_srcroute(); - tcp_lock(oso, 0, 0); + inp->inp_ip_tos = oinp->inp_ip_tos; + } + socket_lock(oso, 0); #if IPSEC /* copy old policy into new socket's */ - if (sotoinpcb(oso)->inp_sp) - { + if (sotoinpcb(oso)->inp_sp) { int error = 0; /* Is it a security hole here to silently fail to copy the policy? */ - if (inp->inp_sp != NULL) + if (inp->inp_sp != NULL) { error = ipsec_init_policy(so, &inp->inp_sp); - if (error != 0 || ipsec_copy_policy(sotoinpcb(oso)->inp_sp, inp->inp_sp)) + } + if (error != 0 || ipsec_copy_policy(sotoinpcb(oso)->inp_sp, inp->inp_sp)) { printf("tcp_input: could not copy policy\n"); + } } #endif /* inherit states from the listener */ DTRACE_TCP4(state__change, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, int32_t, TCPS_LISTEN); + struct tcpcb *, tp, int32_t, TCPS_LISTEN); tp->t_state = TCPS_LISTEN; - tp->t_flags |= tp0->t_flags & (TF_NOPUSH|TF_NOOPT|TF_NODELAY); - tp->t_flagsext |= (tp0->t_flagsext & TF_RXTFINDROP); + tp->t_flags |= tp0->t_flags & (TF_NOPUSH | TF_NOOPT | TF_NODELAY); + tp->t_flagsext |= (tp0->t_flagsext & (TF_RXTFINDROP | TF_NOTIMEWAIT | TF_FASTOPEN)); tp->t_keepinit = tp0->t_keepinit; tp->t_keepcnt = tp0->t_keepcnt; tp->t_keepintvl = tp0->t_keepintvl; tp->t_adaptive_wtimo = tp0->t_adaptive_wtimo; tp->t_adaptive_rtimo = tp0->t_adaptive_rtimo; tp->t_inpcb->inp_ip_ttl = tp0->t_inpcb->inp_ip_ttl; - if ((so->so_flags & SOF_NOTSENT_LOWAT) != 0) + if ((so->so_flags & SOF_NOTSENT_LOWAT) != 0) { tp->t_notsent_lowat = tp0->t_notsent_lowat; + } + tp->t_inpcb->inp_flags2 |= + tp0->t_inpcb->inp_flags2 & INP2_KEEPALIVE_OFFLOAD; /* now drop the reference on the listener */ - tcp_unlock(oso, 1, 0); + socket_unlock(oso, 1); + + tcp_set_max_rwinscale(tp, so, ifp); - tcp_set_max_rwinscale(tp, so); +#if CONTENT_FILTER + if (check_cfil) { + int error = cfil_sock_attach(so2, (struct sockaddr*)&to2, (struct sockaddr*)&from, + CFS_CONNECTION_DIR_IN); + if (error != 0) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, " cfil_sock_attach failed"); + goto drop; + } + } +#endif /* CONTENT_FILTER */ - KERNEL_DEBUG(DBG_FNC_TCP_NEWCONN | DBG_FUNC_END,0,0,0,0,0); + KERNEL_DEBUG(DBG_FNC_TCP_NEWCONN | DBG_FUNC_END, 0, 0, 0, 0, 0); } } - lck_mtx_assert(&((struct inpcb *)so->so_pcb)->inpcb_mtx, LCK_MTX_ASSERT_OWNED); + socket_lock_assert_owned(so); + + if (net_mpklog_enabled && (m->m_pkthdr.rcvif->if_xflags & IFXF_MPK_LOG)) { + MPKL_TCP_INPUT(tcp_mpkl_log_object, + ntohs(tp->t_inpcb->inp_lport), ntohs(tp->t_inpcb->inp_fport), + th->th_seq, th->th_ack, tlen, thflags, + so->last_pid, so->so_log_seqn++); + } if (tp->t_state == TCPS_ESTABLISHED && tlen > 0) { - /* - * Evaluate the rate of arrival of packets to see if the - * receiver can reduce the ack traffic. The algorithm to - * stretch acks will be enabled if the connection meets + /* + * Evaluate the rate of arrival of packets to see if the + * receiver can reduce the ack traffic. The algorithm to + * stretch acks will be enabled if the connection meets * certain criteria defined in tcp_stretch_ack_enable function. */ if ((tp->t_flagsext & TF_RCVUNACK_WAITSS) != 0) { TCP_INC_VAR(tp->rcv_waitforss, nlropkts); } - if (tcp_stretch_ack_enable(tp)) { + if (tcp_stretch_ack_enable(tp, thflags)) { tp->t_flags |= TF_STRETCHACK; tp->t_flagsext &= ~(TF_RCVUNACK_WAITSS); tp->rcv_waitforss = 0; } else { tp->t_flags &= ~(TF_STRETCHACK); } - if (TSTMP_GT(tp->rcv_unackwin, tcp_now)) { + if (TSTMP_GT(tp->rcv_unackwin - (tcp_rcvunackwin >> 1), tcp_now)) { + tp->rcv_by_unackhalfwin += (tlen + off); tp->rcv_by_unackwin += (tlen + off); } else { tp->rcv_unackwin = tcp_now + tcp_rcvunackwin; - tp->rcv_by_unackwin = tlen + off; + tp->rcv_by_unackwin = tp->rcv_by_unackhalfwin + tlen + off; + tp->rcv_by_unackhalfwin = tlen + off; } } - /* + /* * Keep track of how many bytes were received in the LRO packet */ - if ((pktf_sw_lro_pkt) && (nlropkts > 2)) { + if ((pktf_sw_lro_pkt) && (nlropkts > 2)) { tp->t_lropktlen += tlen; } /* * Explicit Congestion Notification - Flag that we need to send ECT if - * + The IP Congestion experienced flag was set. - * + Socket is in established state - * + We negotiated ECN in the TCP setup - * + This isn't a pure ack (tlen > 0) - * + The data is in the valid window + * + The IP Congestion experienced flag was set. + * + Socket is in established state + * + We negotiated ECN in the TCP setup + * + This isn't a pure ack (tlen > 0) + * + The data is in the valid window * - * TE_SENDECE will be cleared when we receive a packet with TH_CWR set. + * TE_SENDECE will be cleared when we receive a packet with TH_CWR set. */ if (ip_ecn == IPTOS_ECN_CE && tp->t_state == TCPS_ESTABLISHED && - ((tp->ecn_flags & (TE_ECN_ON)) == (TE_ECN_ON)) && tlen > 0 && - SEQ_GEQ(th->th_seq, tp->last_ack_sent) && - SEQ_LT(th->th_seq, tp->last_ack_sent + tp->rcv_wnd)) { + TCP_ECN_ENABLED(tp) && tlen > 0 && + SEQ_GEQ(th->th_seq, tp->last_ack_sent) && + SEQ_LT(th->th_seq, tp->last_ack_sent + tp->rcv_wnd)) { + tp->t_ecn_recv_ce++; + tcpstat.tcps_ecn_recv_ce++; + INP_INC_IFNET_STAT(inp, ecn_recv_ce); + /* Mark this connection as it received CE from network */ + tp->ecn_flags |= TE_RECV_ECN_CE; tp->ecn_flags |= TE_SENDECE; } - + /* * Clear TE_SENDECE if TH_CWR is set. This is harmless, so we don't * bother doing extensive checks for state and whatnot. */ - if ((thflags & TH_CWR) == TH_CWR) { + if (thflags & TH_CWR) { tp->ecn_flags &= ~TE_SENDECE; + tp->t_ecn_recv_cwr++; } - /* - * If we received an explicit notification of congestion in + /* + * If we received an explicit notification of congestion in * ip tos ecn bits or by the CWR bit in TCP header flags, reset - * the ack-strteching state. + * the ack-strteching state. We need to handle ECN notification if + * an ECN setup SYN was sent even once. */ - if (tp->t_state == TCPS_ESTABLISHED && - (ip_ecn == IPTOS_ECN_CE || - (thflags & TH_CWR))) + if (tp->t_state == TCPS_ESTABLISHED + && (tp->ecn_flags & TE_SETUPSENT) + && (ip_ecn == IPTOS_ECN_CE || (thflags & TH_CWR))) { tcp_reset_stretch_ack(tp); + CLEAR_IAJ_STATE(tp); + } + + if (ip_ecn == IPTOS_ECN_CE && tp->t_state == TCPS_ESTABLISHED && + !TCP_ECN_ENABLED(tp) && !(tp->ecn_flags & TE_CEHEURI_SET)) { + tcpstat.tcps_ecn_fallback_ce++; + tcp_heuristic_ecn_aggressive(tp); + tp->ecn_flags |= TE_CEHEURI_SET; + } + + if (tp->t_state == TCPS_ESTABLISHED && TCP_ECN_ENABLED(tp) && + ip_ecn == IPTOS_ECN_CE && !(tp->ecn_flags & TE_CEHEURI_SET)) { + if (inp->inp_stat->rxpackets < ECN_MIN_CE_PROBES) { + tp->t_ecn_recv_ce_pkt++; + } else if (tp->t_ecn_recv_ce_pkt > ECN_MAX_CE_RATIO) { + tcpstat.tcps_ecn_fallback_ce++; + tcp_heuristic_ecn_aggressive(tp); + tp->ecn_flags |= TE_CEHEURI_SET; + INP_INC_IFNET_STAT(inp, ecn_fallback_ce); + } else { + /* We tracked the first ECN_MIN_CE_PROBES segments, we + * now know that the path is good. + */ + tp->ecn_flags |= TE_CEHEURI_SET; + } + } - /* + /* * Try to determine if we are receiving a packet after a long time. - * Use our own approximation of idletime to roughly measure remote + * Use our own approximation of idletime to roughly measure remote * end's idle time. Since slowstart is used after an idle period * we want to avoid doing LRO if the remote end is not up to date * on initial window support and starts with 1 or 2 packets as its IW. */ - if (sw_lro && (tp->t_flagsext & TF_LRO_OFFLOADED) && - ((tcp_now - tp->t_rcvtime) >= (TCP_IDLETIMEOUT(tp)))) { + if (sw_lro && (tp->t_flagsext & TF_LRO_OFFLOADED) && + ((tcp_now - tp->t_rcvtime) >= (TCP_IDLETIMEOUT(tp)))) { turnoff_lro = 1; - } + } /* Update rcvtime as a new segment was received on the connection */ tp->t_rcvtime = tcp_now; @@ -2174,65 +3002,59 @@ findpcb: * Segment received on connection. * Reset idle time and keep-alive timer. */ - if (TCPS_HAVEESTABLISHED(tp->t_state)) + if (TCPS_HAVEESTABLISHED(tp->t_state)) { tcp_keepalive_reset(tp); + if (tp->t_mpsub) { + mptcp_reset_keepalive(tp); + } + } + /* * Process options if not in LISTEN state, * else do it below (after getting remote address). */ if (tp->t_state != TCPS_LISTEN && optp) { - tcp_dooptions(tp, optp, optlen, th, &to, ifscope); + tcp_dooptions(tp, optp, optlen, th, &to); + } #if MPTCP - mptcp_csum = mptcp_input_csum(tp, m, drop_hdrlen); - if (mptcp_csum) { - tp->t_mpflags |= TMPF_SND_MPFAIL; - tp->t_mpflags &= ~TMPF_EMBED_DSN; - mptcp_notify_mpfail(so); - m_freem(m); - tcpstat.tcps_mp_badcsum++; - tcp_check_timer_state(tp); - tcp_unlock(so, 1, 0); - KERNEL_DEBUG(DBG_FNC_TCP_INPUT | - DBG_FUNC_END,0,0,0,0,0); - return; - } - mptcp_insert_rmap(tp, m); -#endif /* MPTCP */ + if (tp->t_state != TCPS_LISTEN && (so->so_flags & SOF_MP_SUBFLOW) && + mptcp_input_preproc(tp, m, th, drop_hdrlen) != 0) { + tp->t_flags |= TF_ACKNOW; + (void) tcp_output(tp); + tcp_check_timer_state(tp); + socket_unlock(so, 1); + KERNEL_DEBUG(DBG_FNC_TCP_INPUT | + DBG_FUNC_END, 0, 0, 0, 0, 0); + return; } +#endif /* MPTCP */ if (tp->t_state == TCPS_SYN_SENT && (thflags & TH_SYN)) { - if (to.to_flags & TOF_TS) { - tp->t_flags |= TF_RCVD_TSTMP; - tp->ts_recent = to.to_tsval; - tp->ts_recent_age = tcp_now; - } - if (to.to_flags & TOF_MSS) - tcp_mss(tp, to.to_mss, ifscope); - if (SACK_ENABLED(tp)) { - if (!(to.to_flags & TOF_SACK)) - tp->t_flagsext &= ~(TF_SACK_ENABLE); - else - tp->t_flags |= TF_SACK_PERMIT; + if (!(thflags & TH_ACK) || + (SEQ_GT(th->th_ack, tp->iss) && + SEQ_LEQ(th->th_ack, tp->snd_max))) { + tcp_finalize_options(tp, &to, ifscope); } } #if TRAFFIC_MGT - /* Compute inter-packet arrival jitter. According to RFC 3550, inter-packet - * arrival jitter is defined as the difference in packet spacing at the - * receiver compared to the sender for a pair of packets. When two packets - * of maximum segment size come one after the other with consecutive - * sequence numbers, we consider them as packets sent together at the - * sender and use them as a pair to compute inter-packet arrival jitter. - * This metric indicates the delay induced by the network components due + /* + * Compute inter-packet arrival jitter. According to RFC 3550, + * inter-packet arrival jitter is defined as the difference in + * packet spacing at the receiver compared to the sender for a + * pair of packets. When two packets of maximum segment size come + * one after the other with consecutive sequence numbers, we + * consider them as packets sent together at the sender and use + * them as a pair to compute inter-packet arrival jitter. This + * metric indicates the delay induced by the network components due * to queuing in edge/access routers. */ if (tp->t_state == TCPS_ESTABLISHED && - (thflags & (TH_SYN|TH_FIN|TH_RST|TH_URG|TH_ACK|TH_ECE|TH_PUSH)) == TH_ACK && - ((tp->t_flags & (TF_NEEDSYN|TF_NEEDFIN)) == 0) && + (thflags & (TH_SYN | TH_FIN | TH_RST | TH_URG | TH_ACK | TH_ECE | TH_PUSH)) == TH_ACK && + ((tp->t_flags & (TF_NEEDSYN | TF_NEEDFIN)) == 0) && ((to.to_flags & TOF_TS) == 0 || - TSTMP_GEQ(to.to_tsval, tp->ts_recent)) && - th->th_seq == tp->rcv_nxt && - LIST_EMPTY(&tp->t_segq)) { + TSTMP_GEQ(to.to_tsval, tp->ts_recent)) && + th->th_seq == tp->rcv_nxt && LIST_EMPTY(&tp->t_segq)) { int seg_size = tlen; if (tp->iaj_pktcnt <= IAJ_IGNORE_PKTCNT) { TCP_INC_VAR(tp->iaj_pktcnt, nlropkts); @@ -2241,33 +3063,39 @@ findpcb: if (m->m_pkthdr.pkt_flags & PKTF_SW_LRO_PKT) { seg_size = m->m_pkthdr.lro_pktlen; } - if ( tp->iaj_size == 0 || seg_size > tp->iaj_size || - (seg_size == tp->iaj_size && tp->iaj_rcv_ts == 0)) { - /* State related to inter-arrival jitter is uninitialized - * or we are trying to find a good first packet to start - * computing the metric + if (tp->iaj_size == 0 || seg_size > tp->iaj_size || + (seg_size == tp->iaj_size && tp->iaj_rcv_ts == 0)) { + /* + * State related to inter-arrival jitter is + * uninitialized or we are trying to find a good + * first packet to start computing the metric */ update_iaj_state(tp, seg_size, 0); } else { if (seg_size == tp->iaj_size) { - /* Compute inter-arrival jitter taking this packet - * as the second packet + /* + * Compute inter-arrival jitter taking + * this packet as the second packet */ - if (pktf_sw_lro_pkt) + if (pktf_sw_lro_pkt) { compute_iaj(tp, nlropkts, m->m_pkthdr.lro_elapsed); - else + } else { compute_iaj(tp, 1, 0); - } - if (seg_size < tp->iaj_size) { - /* There is a smaller packet in the stream. - * Some times the maximum size supported on a path can - * change if there is a new link with smaller MTU. - * The receiver will not know about this change. - * If there are too many packets smaller than iaj_size, - * we try to learn the iaj_size again. + } + } + if (seg_size < tp->iaj_size) { + /* + * There is a smaller packet in the stream. + * Some times the maximum size supported + * on a path can change if there is a new + * link with smaller MTU. The receiver will + * not know about this change. If there + * are too many packets smaller than + * iaj_size, we try to learn the iaj_size + * again. */ - TCP_INC_VAR(tp->iaj_small_pkt, nlropkts); + TCP_INC_VAR(tp->iaj_small_pkt, nlropkts); if (tp->iaj_small_pkt > RESET_IAJ_SIZE_THRESH) { update_iaj_state(tp, seg_size, 1); } else { @@ -2300,14 +3128,13 @@ findpcb: * be TH_NEEDSYN. */ if (tp->t_state == TCPS_ESTABLISHED && - (thflags & (TH_SYN|TH_FIN|TH_RST|TH_URG|TH_ACK|TH_ECE)) == TH_ACK && - ((tp->t_flags & (TF_NEEDSYN|TF_NEEDFIN)) == 0) && + (thflags & (TH_SYN | TH_FIN | TH_RST | TH_URG | TH_ACK | TH_ECE | TH_CWR)) == TH_ACK && + ((tp->t_flags & (TF_NEEDSYN | TF_NEEDFIN)) == 0) && ((to.to_flags & TOF_TS) == 0 || - TSTMP_GEQ(to.to_tsval, tp->ts_recent)) && + TSTMP_GEQ(to.to_tsval, tp->ts_recent)) && th->th_seq == tp->rcv_nxt && tiwin && tiwin == tp->snd_wnd && tp->snd_nxt == tp->snd_max) { - /* * If last ACK falls within this segment's sequence numbers, * record the timestamp. @@ -2315,61 +3142,45 @@ findpcb: * proposal of the tcplw@cray.com list (Braden 1993/04/26). */ if ((to.to_flags & TOF_TS) != 0 && - SEQ_LEQ(th->th_seq, tp->last_ack_sent)) { + SEQ_LEQ(th->th_seq, tp->last_ack_sent)) { tp->ts_recent_age = tcp_now; tp->ts_recent = to.to_tsval; } - /* Force acknowledgment if we received a FIN */ - - if (thflags & TH_FIN) - tp->t_flags |= TF_ACKNOW; - if (tlen == 0) { if (SEQ_GT(th->th_ack, tp->snd_una) && SEQ_LEQ(th->th_ack, tp->snd_max) && tp->snd_cwnd >= tp->snd_ssthresh && - (!IN_FASTRECOVERY(tp) && - ((!(SACK_ENABLED(tp)) && tp->t_dupacks < tp->t_rexmtthresh) || - (SACK_ENABLED(tp) && to.to_nsacks == 0 && - TAILQ_EMPTY(&tp->snd_holes))))) { + (!IN_FASTRECOVERY(tp) && + ((!(SACK_ENABLED(tp)) && + tp->t_dupacks < tp->t_rexmtthresh) || + (SACK_ENABLED(tp) && to.to_nsacks == 0 && + TAILQ_EMPTY(&tp->snd_holes))))) { /* * this is a pure ack for outstanding data. */ ++tcpstat.tcps_predack; - /* - * "bad retransmit" recovery - */ - if (tp->t_rxtshift > 0 && - tcp_detect_bad_rexmt(tp, &to)) { - ++tcpstat.tcps_sndrexmitbad; - tcp_bad_rexmt_restore_state(tp, th); - - DTRACE_TCP5(cc, void, NULL, - struct inpcb *, tp->t_inpcb, - struct tcpcb *, tp, struct tcphdr *, th, - int32_t, TCP_CC_BAD_REXMT_RECOVERY); - } + tcp_bad_rexmt_check(tp, th, &to); /* Recalculate the RTT */ tcp_compute_rtt(tp, &to, th); + VERIFY(SEQ_GEQ(th->th_ack, tp->snd_una)); acked = BYTES_ACKED(th, tp); tcpstat.tcps_rcvackpack++; tcpstat.tcps_rcvackbyte += acked; - - /* Handle an ack that is in sequence during congestion - * avoidance phase. The calculations in this function - * assume that snd_una is not updated yet. - */ - if (CC_ALGO(tp)->inseq_ack_rcvd != NULL) - CC_ALGO(tp)->inseq_ack_rcvd(tp, th); - - DTRACE_TCP5(cc, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, struct tcphdr *, th, - int32_t, TCP_CC_INSEQ_ACK_RCVD); + /* + * Handle an ack that is in sequence during + * congestion avoidance phase. The + * calculations in this function + * assume that snd_una is not updated yet. + */ + if (CC_ALGO(tp)->congestion_avd != NULL) { + CC_ALGO(tp)->congestion_avd(tp, th); + } + tcp_ccdbg_trace(tp, th, TCP_CC_INSEQ_ACK_RCVD); sbdrop(&so->so_snd, acked); if (so->so_flags & SOF_ENABLE_MSGS) { VERIFY(acked <= so->so_msg_state->msg_serial_bytes); @@ -2378,10 +3189,13 @@ findpcb: tcp_sbsnd_trim(&so->so_snd); if (SEQ_GT(tp->snd_una, tp->snd_recover) && - SEQ_LEQ(th->th_ack, tp->snd_recover)) + SEQ_LEQ(th->th_ack, tp->snd_recover)) { tp->snd_recover = th->th_ack - 1; + } tp->snd_una = th->th_ack; + TCP_RESET_REXMT_STATE(tp); + /* * pull snd_wl2 up to prevent seq wrap relative * to th_ack. @@ -2404,22 +3218,42 @@ findpcb: * are ready to send, let tcp_output * decide between more output or persist. */ - if (tp->snd_una == tp->snd_max) + if (tp->snd_una == tp->snd_max) { tp->t_timer[TCPT_REXMT] = 0; - else if (tp->t_timer[TCPT_PERSIST] == 0) - tp->t_timer[TCPT_REXMT] = OFFSET_FROM_START(tp, tp->t_rxtcur); + tp->t_timer[TCPT_PTO] = 0; + } else if (tp->t_timer[TCPT_PERSIST] == 0) { + tp->t_timer[TCPT_REXMT] = + OFFSET_FROM_START(tp, + tp->t_rxtcur); + } + if (!SLIST_EMPTY(&tp->t_rxt_segments) && + !TCP_DSACK_SEQ_IN_WINDOW(tp, + tp->t_dsack_lastuna, tp->snd_una)) { + tcp_rxtseg_clean(tp); + } if ((tp->t_flagsext & TF_MEASURESNDBW) != 0 && - tp->t_bwmeas != NULL) + tp->t_bwmeas != NULL) { tcp_bwmeas_check(tp); - sowwakeup(so); /* has to be done with socket lock held */ + } + + write_wakeup = 1; + if (!SLIST_EMPTY(&tp->t_notify_ack)) { + tcp_notify_acknowledgement(tp, so); + } + if ((so->so_snd.sb_cc) || (tp->t_flags & TF_ACKNOW)) { (void) tcp_output(tp); } + tcp_tfo_rcv_ack(tp, th); + tcp_check_timer_state(tp); - tcp_unlock(so, 1, 0); - KERNEL_DEBUG(DBG_FNC_TCP_INPUT | DBG_FUNC_END,0,0,0,0,0); + + tcp_handle_wakeup(so, read_wakeup, write_wakeup); + + socket_unlock(so, 1); + KERNEL_DEBUG(DBG_FNC_TCP_INPUT | DBG_FUNC_END, 0, 0, 0, 0, 0); return; } } else if (th->th_ack == tp->snd_una && @@ -2432,32 +3266,33 @@ findpcb: */ /* - * If this is a connection in steady state, start + * If this is a connection in steady state, start * coalescing packets belonging to this flow. */ if (turnoff_lro) { tcp_lro_remove_state(tp->t_inpcb->inp_laddr, - tp->t_inpcb->inp_faddr, - tp->t_inpcb->inp_lport, - tp->t_inpcb->inp_fport); + tp->t_inpcb->inp_faddr, + tp->t_inpcb->inp_lport, + tp->t_inpcb->inp_fport); tp->t_flagsext &= ~TF_LRO_OFFLOADED; tp->t_idleat = tp->rcv_nxt; } else if (sw_lro && !pktf_sw_lro_pkt && !isipv6 && - (so->so_flags & SOF_USELRO) && + (so->so_flags & SOF_USELRO) && !IFNET_IS_CELLULAR(m->m_pkthdr.rcvif) && - (m->m_pkthdr.rcvif->if_type != IFT_LOOP) && - ((th->th_seq - tp->irs) > + (m->m_pkthdr.rcvif->if_type != IFT_LOOP) && + ((th->th_seq - tp->irs) > (tp->t_maxseg << lro_start)) && - ((tp->t_idleat == 0) || ((th->th_seq - - tp->t_idleat) > (tp->t_maxseg << lro_start)))) { + ((tp->t_idleat == 0) || ((th->th_seq - + tp->t_idleat) > (tp->t_maxseg << lro_start)))) { tp->t_flagsext |= TF_LRO_OFFLOADED; tcp_start_coalescing(ip, th, tlen); tp->t_idleat = 0; } /* Clean receiver SACK report if present */ - if (SACK_ENABLED(tp) && tp->rcv_numsacks) + if (SACK_ENABLED(tp) && tp->rcv_numsacks) { tcp_clean_sackreport(tp); + } ++tcpstat.tcps_preddat; tp->rcv_nxt += tlen; /* @@ -2474,57 +3309,71 @@ findpcb: tcpstat.tcps_rcvbyte += tlen; if (nstat_collect) { if (m->m_pkthdr.pkt_flags & PKTF_SW_LRO_PKT) { - INP_ADD_STAT(inp, cell, wifi, rxpackets, - m->m_pkthdr.lro_npkts); + INP_ADD_STAT(inp, cell, wifi, wired, + rxpackets, m->m_pkthdr.lro_npkts); } else { - INP_ADD_STAT(inp, cell, wifi, rxpackets, 1); + INP_ADD_STAT(inp, cell, wifi, wired, + rxpackets, 1); } - INP_ADD_STAT(inp, cell, wifi, rxbytes, tlen); + INP_ADD_STAT(inp, cell, wifi, wired, rxbytes, + tlen); + inp_set_activity_bitmap(inp); } /* - * Calculate the RTT on the receiver only if the - * connection is in streaming mode and the last + * Calculate the RTT on the receiver only if the + * connection is in streaming mode and the last * packet was not an end-of-write */ - if ((tp->t_flags & TF_STRETCHACK) && - !(tp->t_flagsext & TF_STREAMEOW)) + if (tp->t_flags & TF_STREAMING_ON) { tcp_compute_rtt(tp, &to, th); + } + + tcp_sbrcv_grow(tp, &so->so_rcv, &to, tlen, + TCP_AUTORCVBUF_MAX(ifp)); - tcp_sbrcv_grow(tp, &so->so_rcv, &to, tlen); - /* * Add data to socket buffer. */ so_recv_data_stat(so, m, 0); - m_adj(m, drop_hdrlen); /* delayed header drop */ - + m_adj(m, drop_hdrlen); /* delayed header drop */ + /* - * If message delivery (SOF_ENABLE_MSGS) is enabled on + * If message delivery (SOF_ENABLE_MSGS) is enabled on * this socket, deliver the packet received as an * in-order message with sequence number attached to it. */ - if (sbappendstream_rcvdemux(so, m, + if (isipv6) { + memcpy(&saved_hdr, ip6, sizeof(struct ip6_hdr)); + ip6 = (struct ip6_hdr *)&saved_hdr[0]; + } else { + memcpy(&saved_hdr, ip, ip->ip_hl << 2); + ip = (struct ip *)&saved_hdr[0]; + } + memcpy(&saved_tcphdr, th, sizeof(struct tcphdr)); + if (sbappendstream_rcvdemux(so, m, th->th_seq - (tp->irs + 1), 0)) { - sorwakeup(so); - } + mptcp_handle_input(so); + read_wakeup = 1; + } + th = &saved_tcphdr; + #if INET6 if (isipv6) { KERNEL_DEBUG(DBG_LAYER_END, ((th->th_dport << 16) | th->th_sport), - (((ip6->ip6_src.s6_addr16[0]) << 16) | (ip6->ip6_dst.s6_addr16[0])), - th->th_seq, th->th_ack, th->th_win); - } - else -#endif + (((ip6->ip6_src.s6_addr16[0]) << 16) | (ip6->ip6_dst.s6_addr16[0])), + th->th_seq, th->th_ack, th->th_win); + } else +#endif { KERNEL_DEBUG(DBG_LAYER_END, ((th->th_dport << 16) | th->th_sport), - (((ip->ip_src.s_addr & 0xffff) << 16) | (ip->ip_dst.s_addr & 0xffff)), - th->th_seq, th->th_ack, th->th_win); + (((ip->ip_src.s_addr & 0xffff) << 16) | (ip->ip_dst.s_addr & 0xffff)), + th->th_seq, th->th_ack, th->th_win); } TCP_INC_VAR(tp->t_unacksegs, nlropkts); - if (DELAY_ACK(tp, th)) { + if (DELAY_ACK(tp, th)) { if ((tp->t_flags & TF_DELACK) == 0) { - tp->t_flags |= TF_DELACK; + tp->t_flags |= TF_DELACK; tp->t_timer[TCPT_DELACK] = OFFSET_FROM_START(tp, tcp_delack); } } else { @@ -2534,9 +3383,16 @@ findpcb: tcp_adaptive_rwtimo_check(tp, tlen); + if (tlen > 0) { + tcp_tfo_rcv_data(tp); + } + tcp_check_timer_state(tp); - tcp_unlock(so, 1, 0); - KERNEL_DEBUG(DBG_FNC_TCP_INPUT | DBG_FUNC_END,0,0,0,0,0); + + tcp_handle_wakeup(so, read_wakeup, write_wakeup); + + socket_unlock(so, 1); + KERNEL_DEBUG(DBG_FNC_TCP_INPUT | DBG_FUNC_END, 0, 0, 0, 0, 0); return; } } @@ -2547,13 +3403,14 @@ findpcb: * Receive window is amount of space in rcv queue, * but not less than advertised window. */ - lck_mtx_assert(&((struct inpcb *)so->so_pcb)->inpcb_mtx, LCK_MTX_ASSERT_OWNED); + socket_lock_assert_owned(so); win = tcp_sbspace(tp); - if (win < 0) + if (win < 0) { win = 0; - else { /* clip rcv window to 4K for modems */ - if (tp->t_flags & TF_SLOWLINK && slowlink_wsize > 0) + } else { /* clip rcv window to 4K for modems */ + if (tp->t_flags & TF_SLOWLINK && slowlink_wsize > 0) { win = min(win, slowlink_wsize); + } } tp->rcv_wnd = imax(win, (int)(tp->rcv_adv - tp->rcv_nxt)); #if MPTCP @@ -2563,17 +3420,16 @@ findpcb: */ if ((tp->t_mpflags & TMPF_MPTCP_TRUE) && (mp_tp = tptomptp(tp))) { - MPT_LOCK(mp_tp); - if (tp->rcv_wnd > mp_tp->mpt_rcvwnd) { - tp->rcv_wnd = mp_tp->mpt_rcvwnd; + socket_lock_assert_owned(mptetoso(mp_tp->mpt_mpte)); + + if (tp->rcv_wnd > (int)(mp_tp->mpt_rcvadv - (uint32_t)mp_tp->mpt_rcvnxt)) { + tp->rcv_wnd = mp_tp->mpt_rcvadv - (uint32_t)mp_tp->mpt_rcvnxt; tcpstat.tcps_mp_reducedwin++; } - MPT_UNLOCK(mp_tp); } #endif /* MPTCP */ switch (tp->t_state) { - /* * Initialize tp->rcv_nxt, and tp->irs, select an initial * tp->iss, and send a segment: @@ -2584,72 +3440,83 @@ findpcb: * segment in this state. */ case TCPS_LISTEN: { - register struct sockaddr_in *sin; + struct sockaddr_in *sin; #if INET6 - register struct sockaddr_in6 *sin6; + struct sockaddr_in6 *sin6; #endif - lck_mtx_assert(&((struct inpcb *)so->so_pcb)->inpcb_mtx, LCK_MTX_ASSERT_OWNED); + socket_lock_assert_owned(so); + + /* Clear the logging flags inherited from the listening socket */ + tp->t_log_flags = 0; + tp->t_flagsext &= ~TF_LOGGED_CONN_SUMMARY; + #if INET6 if (isipv6) { MALLOC(sin6, struct sockaddr_in6 *, sizeof *sin6, - M_SONAME, M_NOWAIT); - if (sin6 == NULL) + M_SONAME, M_NOWAIT); + if (sin6 == NULL) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "LISTEN malloc M_SONAME failed"); goto drop; + } bzero(sin6, sizeof(*sin6)); sin6->sin6_family = AF_INET6; sin6->sin6_len = sizeof(*sin6); sin6->sin6_addr = ip6->ip6_src; sin6->sin6_port = th->th_sport; laddr6 = inp->in6p_laddr; - if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) + if (IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_laddr)) { inp->in6p_laddr = ip6->ip6_dst; + } if (in6_pcbconnect(inp, (struct sockaddr *)sin6, - proc0)) { + proc0)) { inp->in6p_laddr = laddr6; FREE(sin6, M_SONAME); + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, " LISTEN in6_pcbconnect failed"); goto drop; } FREE(sin6, M_SONAME); } else #endif - { - lck_mtx_assert(&((struct inpcb *)so->so_pcb)->inpcb_mtx, LCK_MTX_ASSERT_OWNED); + { + socket_lock_assert_owned(so); MALLOC(sin, struct sockaddr_in *, sizeof *sin, M_SONAME, - M_NOWAIT); - if (sin == NULL) + M_NOWAIT); + if (sin == NULL) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "LISTEN malloc M_SONAME failed"); goto drop; + } sin->sin_family = AF_INET; sin->sin_len = sizeof(*sin); sin->sin_addr = ip->ip_src; sin->sin_port = th->th_sport; bzero((caddr_t)sin->sin_zero, sizeof(sin->sin_zero)); laddr = inp->inp_laddr; - if (inp->inp_laddr.s_addr == INADDR_ANY) + if (inp->inp_laddr.s_addr == INADDR_ANY) { inp->inp_laddr = ip->ip_dst; + } if (in_pcbconnect(inp, (struct sockaddr *)sin, proc0, IFSCOPE_NONE, NULL)) { inp->inp_laddr = laddr; FREE(sin, M_SONAME); + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, " LISTEN in_pcbconnect failed"); goto drop; } FREE(sin, M_SONAME); } - tcp_dooptions(tp, optp, optlen, th, &to, ifscope); + tcp_dooptions(tp, optp, optlen, th, &to); + tcp_finalize_options(tp, &to, ifscope); - if (SACK_ENABLED(tp)) { - if (!(to.to_flags & TOF_SACK)) - tp->t_flagsext &= ~(TF_SACK_ENABLE); - else - tp->t_flags |= TF_SACK_PERMIT; + if (tfo_enabled(tp) && tcp_tfo_syn(tp, &to)) { + isconnected = TRUE; } - - if (iss) + + if (iss) { tp->iss = iss; - else { + } else { tp->iss = tcp_new_isn(tp); - } + } tp->irs = th->th_seq; tcp_sendseqinit(tp); tcp_rcvseqinit(tp); @@ -2659,18 +3526,21 @@ findpcb: * set SND.WND = SEG.WND, * initialize CCsend and CCrecv. */ - tp->snd_wnd = tiwin; /* initial send-window */ + tp->snd_wnd = tiwin; /* initial send-window */ + tp->max_sndwnd = tp->snd_wnd; tp->t_flags |= TF_ACKNOW; tp->t_unacksegs = 0; DTRACE_TCP4(state__change, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, int32_t, TCPS_SYN_RECEIVED); + struct tcpcb *, tp, int32_t, TCPS_SYN_RECEIVED); tp->t_state = TCPS_SYN_RECEIVED; - tp->t_timer[TCPT_KEEP] = OFFSET_FROM_START(tp, - TCP_CONN_KEEPINIT(tp)); - dropsocket = 0; /* committed to socket */ + tp->t_timer[TCPT_KEEP] = OFFSET_FROM_START(tp, + TCP_CONN_KEEPINIT(tp)); + tp->t_connect_time = tcp_now; + dropsocket = 0; /* committed to socket */ - if (inp->inp_flowhash == 0) + if (inp->inp_flowhash == 0) { inp->inp_flowhash = inp_calc_flowhash(inp); + } #if INET6 /* update flowinfo - RFC 6437 */ if (inp->inp_flow == 0 && @@ -2689,27 +3559,26 @@ findpcb: tp->ecn_flags |= (TE_SETUPRECEIVED | TE_SENDIPECT); } -#if CONFIG_IFEF_NOWINDOWSCALE - if (tcp_obey_ifef_nowindowscale && m->m_pkthdr.rcvif != NULL && - (m->m_pkthdr.rcvif->if_eflags & IFEF_NOWINDOWSCALE)) { - /* Window scaling is not enabled on this interface */ - tp->t_flags &= ~TF_REQ_SCALE; - } -#endif + /* + * The address and connection state are finalized + */ + TCP_LOG_CONNECT(tp, false, 0); + goto trimthenstep6; - } + } /* - * If the state is SYN_RECEIVED: - * if seg contains an ACK, but not for our SYN/ACK, send a RST. + * If the state is SYN_RECEIVED and the seg contains an ACK, + * but not for our SYN/ACK, send a RST. */ case TCPS_SYN_RECEIVED: if ((thflags & TH_ACK) && (SEQ_LEQ(th->th_ack, tp->snd_una) || - SEQ_GT(th->th_ack, tp->snd_max))) { - rstreason = BANDLIM_RST_OPENPORT; - IF_TCP_STATINC(ifp, ooopacket); - goto dropwithreset; + SEQ_GT(th->th_ack, tp->snd_max))) { + rstreason = BANDLIM_RST_OPENPORT; + IF_TCP_STATINC(ifp, ooopacket); + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "SYN_RECEIVED bad ACK"); + goto dropwithreset; } /* @@ -2719,8 +3588,10 @@ findpcb: * lower if we assume scaling and the other end does not. */ if ((thflags & TH_SYN) && - !(to.to_flags & TOF_SCALE)) + (tp->irs == th->th_seq) && + !(to.to_flags & TOF_SCALE)) { tp->t_flags &= ~TF_RCVD_SCALE; + } break; /* @@ -2738,64 +3609,130 @@ findpcb: case TCPS_SYN_SENT: if ((thflags & TH_ACK) && (SEQ_LEQ(th->th_ack, tp->iss) || - SEQ_GT(th->th_ack, tp->snd_max))) { + SEQ_GT(th->th_ack, tp->snd_max))) { rstreason = BANDLIM_UNLIMITED; IF_TCP_STATINC(ifp, ooopacket); + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "SYN_SENT bad ACK"); goto dropwithreset; } if (thflags & TH_RST) { if ((thflags & TH_ACK) != 0) { - soevent(so, + if (tfo_enabled(tp) && + !(tp->t_flagsext & TF_FASTOPEN_FORCE_ENABLE)) { + tcp_heuristic_tfo_rst(tp); + } + if ((tp->ecn_flags & (TE_SETUPSENT | TE_RCVD_SYN_RST)) == TE_SETUPSENT) { + /* + * On local connections, send + * non-ECN syn one time before + * dropping the connection + */ + if (tp->t_flags & TF_LOCAL) { + tp->ecn_flags |= TE_RCVD_SYN_RST; + goto drop; + } else { + tcp_heuristic_ecn_synrst(tp); + } + } + soevent(so, (SO_FILT_HINT_LOCKED | SO_FILT_HINT_CONNRESET)); tp = tcp_drop(tp, ECONNREFUSED); postevent(so, 0, EV_RESET); } + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "SYN_SENT got RST"); goto drop; } - if ((thflags & TH_SYN) == 0) + if ((thflags & TH_SYN) == 0) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "SYN_SENT no SYN"); goto drop; - tp->snd_wnd = th->th_win; /* initial send window */ + } + tp->snd_wnd = th->th_win; /* initial send window */ + tp->max_sndwnd = tp->snd_wnd; tp->irs = th->th_seq; tcp_rcvseqinit(tp); if (thflags & TH_ACK) { tcpstat.tcps_connects++; - + if ((thflags & (TH_ECE | TH_CWR)) == (TH_ECE)) { /* ECN-setup SYN-ACK */ tp->ecn_flags |= TE_SETUPRECEIVED; - } - else { + if (TCP_ECN_ENABLED(tp)) { + tcp_heuristic_ecn_success(tp); + tcpstat.tcps_ecn_client_success++; + } + } else { + if (tp->ecn_flags & TE_SETUPSENT && + tp->t_rxtshift == 0) { + tcp_heuristic_ecn_success(tp); + tcpstat.tcps_ecn_not_supported++; + } + if (tp->ecn_flags & TE_SETUPSENT && + tp->t_rxtshift > 0) { + tcp_heuristic_ecn_loss(tp); + } + /* non-ECN-setup SYN-ACK */ tp->ecn_flags &= ~TE_SENDIPECT; } - + #if CONFIG_MACF_NET && CONFIG_MACF_SOCKET /* XXXMAC: recursive lock: SOCK_LOCK(so); */ mac_socketpeer_label_associate_mbuf(m, so); /* XXXMAC: SOCK_UNLOCK(so); */ #endif /* Do window scaling on this connection? */ - if ((tp->t_flags & (TF_RCVD_SCALE|TF_REQ_SCALE)) == - (TF_RCVD_SCALE|TF_REQ_SCALE)) { + if (TCP_WINDOW_SCALE_ENABLED(tp)) { tp->snd_scale = tp->requested_s_scale; tp->rcv_scale = tp->request_r_scale; } + tp->rcv_adv += min(tp->rcv_wnd, TCP_MAXWIN << tp->rcv_scale); - tp->snd_una++; /* SYN is acked */ + tp->snd_una++; /* SYN is acked */ + if (SEQ_LT(tp->snd_nxt, tp->snd_una)) { + tp->snd_nxt = tp->snd_una; + } + + /* + * We have sent more in the SYN than what is being + * acked. (e.g., TFO) + * We should restart the sending from what the receiver + * has acknowledged immediately. + */ + if (SEQ_GT(tp->snd_nxt, th->th_ack)) { + /* + * rdar://problem/33214601 + * There is a middlebox that acks all but one + * byte and still drops the data. + */ + if (!(tp->t_flagsext & TF_FASTOPEN_FORCE_ENABLE) && + (tp->t_tfo_stats & TFO_S_SYN_DATA_SENT) && + tp->snd_max == th->th_ack + 1 && + tp->snd_max > tp->snd_una + 1) { + tcp_heuristic_tfo_middlebox(tp); + + so->so_error = ENODATA; + soevent(so, + (SO_FILT_HINT_LOCKED | SO_FILT_HINT_MP_SUB_ERROR)); + + tp->t_tfo_stats |= TFO_S_ONE_BYTE_PROXY; + } + + tp->snd_max = tp->snd_nxt = th->th_ack; + } + /* * If there's data, delay ACK; if there's also a FIN * ACKNOW will be turned on later. */ TCP_INC_VAR(tp->t_unacksegs, nlropkts); - if (DELAY_ACK(tp, th) && tlen != 0 ) { + if (DELAY_ACK(tp, th) && tlen != 0) { if ((tp->t_flags & TF_DELACK) == 0) { tp->t_flags |= TF_DELACK; tp->t_timer[TCPT_DELACK] = OFFSET_FROM_START(tp, tcp_delack); } - } - else { + } else { tp->t_flags |= TF_ACKNOW; } /* @@ -2807,19 +3744,33 @@ findpcb: tp->t_starttime = tcp_now; tcp_sbrcv_tstmp_check(tp); if (tp->t_flags & TF_NEEDFIN) { - DTRACE_TCP4(state__change, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, int32_t, TCPS_FIN_WAIT_1); + DTRACE_TCP4(state__change, void, NULL, + struct inpcb *, inp, + struct tcpcb *, tp, int32_t, + TCPS_FIN_WAIT_1); tp->t_state = TCPS_FIN_WAIT_1; tp->t_flags &= ~TF_NEEDFIN; thflags &= ~TH_SYN; + + TCP_LOG_CONNECTION_SUMMARY(tp); } else { - DTRACE_TCP4(state__change, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, int32_t, TCPS_ESTABLISHED); + DTRACE_TCP4(state__change, void, NULL, + struct inpcb *, inp, struct tcpcb *, + tp, int32_t, TCPS_ESTABLISHED); tp->t_state = TCPS_ESTABLISHED; - tp->t_timer[TCPT_KEEP] = OFFSET_FROM_START(tp, - TCP_CONN_KEEPIDLE(tp)); - if (nstat_collect) - nstat_route_connect_success(tp->t_inpcb->inp_route.ro_rt); + tp->t_timer[TCPT_KEEP] = + OFFSET_FROM_START(tp, + TCP_CONN_KEEPIDLE(tp)); + if (nstat_collect) { + nstat_route_connect_success( + inp->inp_route.ro_rt); + } + /* + * The SYN is acknowledged but una is not + * updated yet. So pass the value of + * ack to compute sndbytes correctly + */ + inp_count_sndbytes(inp, th->th_ack); } #if MPTCP /* @@ -2831,11 +3782,28 @@ findpcb: isconnected = FALSE; } else #endif /* MPTCP */ - isconnected = TRUE; + isconnected = TRUE; + + if ((tp->t_tfo_flags & (TFO_F_COOKIE_REQ | TFO_F_COOKIE_SENT)) || + (tp->t_tfo_stats & TFO_S_SYN_DATA_SENT)) { + tcp_tfo_synack(tp, &to); + + if ((tp->t_tfo_stats & TFO_S_SYN_DATA_SENT) && + SEQ_LT(tp->snd_una, th->th_ack)) { + tp->t_tfo_stats |= TFO_S_SYN_DATA_ACKED; + tcpstat.tcps_tfo_syn_data_acked++; +#if MPTCP + if (so->so_flags & SOF_MP_SUBFLOW) { + so->so_flags1 |= SOF1_TFO_REWIND; + } +#endif + tcp_tfo_rcv_probe(tp, tlen); + } + } } else { /* * Received initial SYN in SYN-SENT[*] state => simul- - * taneous open. If segment contains CC option and there is + * taneous open. If segment contains CC option and there is * a cached CC, apply TAO test; if it succeeds, connection is * half-synchronized. Otherwise, do 3-way handshake: * SYN-SENT -> SYN-RECEIVED @@ -2844,9 +3812,15 @@ findpcb: tp->t_flags |= TF_ACKNOW; tp->t_timer[TCPT_REXMT] = 0; DTRACE_TCP4(state__change, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, int32_t, TCPS_SYN_RECEIVED); + struct tcpcb *, tp, int32_t, TCPS_SYN_RECEIVED); tp->t_state = TCPS_SYN_RECEIVED; + /* + * During simultaneous open, TFO should not be used. + * So, we disable it here, to prevent that data gets + * sent on the SYN/ACK. + */ + tcp_disable_tfo(tp); } trimthenstep6: @@ -2873,8 +3847,9 @@ trimthenstep6: * processing in the middle of step 5, ack processing. * Otherwise, goto step 6. */ - if (thflags & TH_ACK) + if (thflags & TH_ACK) { goto process_ACK; + } goto step6; /* * If the state is LAST_ACK or CLOSING or TIME_WAIT: @@ -2885,16 +3860,27 @@ trimthenstep6: case TCPS_LAST_ACK: case TCPS_CLOSING: case TCPS_TIME_WAIT: - break; /* continue normal processing */ + break; /* continue normal processing */ /* Received a SYN while connection is already established. * This is a "half open connection and other anomalies" described * in RFC793 page 34, send an ACK so the remote reset the connection - * or recovers by adjusting its sequence numberering + * or recovers by adjusting its sequence numbering. Sending an ACK is + * in accordance with RFC 5961 Section 4.2 */ case TCPS_ESTABLISHED: - if (thflags & TH_SYN) - goto dropafterack; + if (thflags & TH_SYN) { + /* Drop the packet silently if we have reached the limit */ + if (tcp_do_rfc5961 && tcp_is_ack_ratelimited(tp)) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "ESTABLISHED rfc5961 rate limited"); + goto drop; + } else { + /* Send challenge ACK */ + tcpstat.tcps_synchallenge++; + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "ESTABLISHED rfc5961 challenge ACK"); + goto dropafterack; + } + } break; } @@ -2932,6 +3918,11 @@ trimthenstep6: * only accepting RSTs where the sequence number is equal to * last_ack_sent. In all other states (the states in which a * RST is more likely), the more permissive check is used. + * RFC 5961 Section 3.2: if the RST bit is set, sequence # is + * within the receive window and last_ack_sent == seq, + * then reset the connection. Otherwise if the seq doesn't + * match last_ack_sent, TCP must send challenge ACK. Perform + * rate limitation when sending the challenge ACK. * If we have multiple segments in flight, the intial reset * segment sequence numbers will be to the left of last_ack_sent, * but they will eventually catch up. @@ -2964,50 +3955,74 @@ trimthenstep6: * there is already a RST in flight from the peer. * In that case, accept the RST for non-established * state if it's one off from last_ack_sent. - + * */ if (thflags & TH_RST) { if ((SEQ_GEQ(th->th_seq, tp->last_ack_sent) && SEQ_LT(th->th_seq, tp->last_ack_sent + tp->rcv_wnd)) || - (tp->rcv_wnd == 0 && - ((tp->last_ack_sent == th->th_seq) || - ((tp->last_ack_sent -1) == th->th_seq)))) { - switch (tp->t_state) { - - case TCPS_SYN_RECEIVED: - IF_TCP_STATINC(ifp, rstinsynrcv); - so->so_error = ECONNREFUSED; - goto close; - - case TCPS_ESTABLISHED: - if (tp->last_ack_sent != th->th_seq) { - tcpstat.tcps_badrst++; - goto drop; - } - case TCPS_FIN_WAIT_1: - case TCPS_CLOSE_WAIT: + (tp->rcv_wnd == 0 && + ((tp->last_ack_sent == th->th_seq) || + ((tp->last_ack_sent - 1) == th->th_seq)))) { + if (tcp_do_rfc5961 == 0 || tp->last_ack_sent == th->th_seq) { + switch (tp->t_state) { + case TCPS_SYN_RECEIVED: + IF_TCP_STATINC(ifp, rstinsynrcv); + so->so_error = ECONNREFUSED; + goto close; + + case TCPS_ESTABLISHED: + if (tcp_do_rfc5961 == 0 && tp->last_ack_sent != th->th_seq) { + tcpstat.tcps_badrst++; + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "ESTABLISHED rfc5961 bad RST"); + goto drop; + } + if (TCP_ECN_ENABLED(tp) && + tp->snd_una == tp->iss + 1 && + SEQ_GT(tp->snd_max, tp->snd_una)) { + /* + * If the first data packet on an + * ECN connection, receives a RST + * increment the heuristic + */ + tcp_heuristic_ecn_droprst(tp); + } + case TCPS_FIN_WAIT_1: + case TCPS_CLOSE_WAIT: /* - Drop through ... - */ - case TCPS_FIN_WAIT_2: - so->so_error = ECONNRESET; - close: - postevent(so, 0, EV_RESET); - soevent(so, - (SO_FILT_HINT_LOCKED | - SO_FILT_HINT_CONNRESET)); - - tcpstat.tcps_drops++; - tp = tcp_close(tp); - break; + * Drop through ... + */ + case TCPS_FIN_WAIT_2: + so->so_error = ECONNRESET; +close: + postevent(so, 0, EV_RESET); + soevent(so, + (SO_FILT_HINT_LOCKED | + SO_FILT_HINT_CONNRESET)); + + tcpstat.tcps_drops++; + tp = tcp_close(tp); + break; - case TCPS_CLOSING: - case TCPS_LAST_ACK: - tp = tcp_close(tp); - break; + case TCPS_CLOSING: + case TCPS_LAST_ACK: + tp = tcp_close(tp); + break; - case TCPS_TIME_WAIT: - break; + case TCPS_TIME_WAIT: + break; + } + } else if (tcp_do_rfc5961) { + tcpstat.tcps_badrst++; + /* Drop if we have reached the ACK limit */ + if (tcp_is_ack_ratelimited(tp)) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "ESTABLISHED rfc5961 rate limited"); + goto drop; + } else { + /* Send challenge ACK */ + tcpstat.tcps_rstchallenge++; + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "ESTABLISHED rfc5961 challenge ACK"); + goto dropafterack; + } } } goto drop; @@ -3019,7 +4034,6 @@ trimthenstep6: */ if ((to.to_flags & TOF_TS) != 0 && tp->ts_recent && TSTMP_LT(to.to_tsval, tp->ts_recent)) { - /* Check to see if ts_recent is over 24 days old. */ if ((int)(tcp_now - tp->ts_recent_age) > TCP_PAWS_IDLE) { /* @@ -3037,16 +4051,37 @@ trimthenstep6: } else { tcpstat.tcps_rcvduppack++; tcpstat.tcps_rcvdupbyte += tlen; + tp->t_pawsdrop++; tcpstat.tcps_pawsdrop++; + + /* + * PAWS-drop when ECN is being used? That indicates + * that ECT-marked packets take a different path, with + * different congestion-characteristics. + * + * Only fallback when we did send less than 2GB as PAWS + * really has no reason to kick in earlier. + */ + if (TCP_ECN_ENABLED(tp) && + inp->inp_stat->rxbytes < 2147483648) { + INP_INC_IFNET_STAT(inp, ecn_fallback_reorder); + tcpstat.tcps_ecn_fallback_reorder++; + tcp_heuristic_ecn_aggressive(tp); + } + if (nstat_collect) { - nstat_route_rx(tp->t_inpcb->inp_route.ro_rt, - 1, tlen, NSTAT_RX_FLAG_DUPLICATE); - INP_ADD_STAT(inp, cell, wifi, rxpackets, 1); - INP_ADD_STAT(inp, cell, wifi, rxbytes, tlen); + nstat_route_rx(tp->t_inpcb->inp_route.ro_rt, + 1, tlen, NSTAT_RX_FLAG_DUPLICATE); + INP_ADD_STAT(inp, cell, wifi, wired, + rxpackets, 1); + INP_ADD_STAT(inp, cell, wifi, wired, + rxbytes, tlen); tp->t_stat.rxduplicatebytes += tlen; + inp_set_activity_bitmap(inp); } - if (tlen) + if (tlen > 0) { goto dropafterack; + } goto drop; } } @@ -3061,22 +4096,33 @@ trimthenstep6: if (tp->t_state == TCPS_SYN_RECEIVED && SEQ_LT(th->th_seq, tp->irs)) { rstreason = BANDLIM_RST_OPENPORT; IF_TCP_STATINC(ifp, dospacket); + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "SYN_RECEIVED bad SEQ"); goto dropwithreset; } + /* + * Check if there is old data at the beginning of the window + * i.e. the sequence number is before rcv_nxt + */ todrop = tp->rcv_nxt - th->th_seq; if (todrop > 0) { + boolean_t is_syn_set = FALSE; + if (thflags & TH_SYN) { + is_syn_set = TRUE; thflags &= ~TH_SYN; th->th_seq++; - if (th->th_urp > 1) + if (th->th_urp > 1) { th->th_urp--; - else + } else { thflags &= ~TH_URG; + } todrop--; } /* * Following if statement from Stevens, vol. 2, p. 960. + * The amount of duplicate data is greater than or equal + * to the size of the segment - entire segment is duplicate */ if (todrop > tlen || (todrop == tlen && (thflags & TH_FIN) == 0)) { @@ -3090,60 +4136,103 @@ trimthenstep6: /* * Send an ACK to resynchronize and drop any data. * But keep on processing for RST or ACK. + * + * If the SYN bit was originally set, then only send + * an ACK if we are not rate-limiting this connection. */ - tp->t_flags |= TF_ACKNOW; + if (tcp_do_rfc5961 && is_syn_set) { + if (!tcp_is_ack_ratelimited(tp)) { + tcpstat.tcps_synchallenge++; + tp->t_flags |= TF_ACKNOW; + } + } else { + tp->t_flags |= TF_ACKNOW; + } + if (todrop == 1) { /* This could be a keepalive */ soevent(so, SO_FILT_HINT_LOCKED | - SO_FILT_HINT_KEEPALIVE); + SO_FILT_HINT_KEEPALIVE); } todrop = tlen; tcpstat.tcps_rcvduppack++; - tcpstat.tcps_rcvdupbyte += todrop; + tcpstat.tcps_rcvdupbyte += todrop; } else { tcpstat.tcps_rcvpartduppack++; tcpstat.tcps_rcvpartdupbyte += todrop; } + + if (TCP_DSACK_ENABLED(tp) && todrop > 1) { + /* + * Note the duplicate data sequence space so that + * it can be reported in DSACK option. + */ + tp->t_dsack_lseq = th->th_seq; + tp->t_dsack_rseq = th->th_seq + todrop; + tp->t_flags |= TF_ACKNOW; + } if (nstat_collect) { - nstat_route_rx(tp->t_inpcb->inp_route.ro_rt, 1, - todrop, NSTAT_RX_FLAG_DUPLICATE); - INP_ADD_STAT(inp, cell, wifi, rxpackets, 1); - INP_ADD_STAT(inp, cell, wifi, rxbytes, todrop); + nstat_route_rx(tp->t_inpcb->inp_route.ro_rt, 1, + todrop, NSTAT_RX_FLAG_DUPLICATE); + INP_ADD_STAT(inp, cell, wifi, wired, rxpackets, 1); + INP_ADD_STAT(inp, cell, wifi, wired, rxbytes, todrop); tp->t_stat.rxduplicatebytes += todrop; + inp_set_activity_bitmap(inp); } - drop_hdrlen += todrop; /* drop from the top afterwards */ + drop_hdrlen += todrop; /* drop from the top afterwards */ th->th_seq += todrop; tlen -= todrop; - if (th->th_urp > todrop) + if (th->th_urp > todrop) { th->th_urp -= todrop; - else { + } else { thflags &= ~TH_URG; th->th_urp = 0; } } /* - * If new data are received on a connection after the user processes - * are gone, then RST the other end. Note that an MPTCP subflow socket - * would have SS_NOFDREF set by default, so check to make sure that - * we test for SOF_MP_SUBFLOW socket flag (which would be cleared when - * the socket is closed.) + * If new data are received on a connection after the user + * processes are gone, then RST the other end. + * Send also a RST when we received a data segment after we've + * sent our FIN when the socket is defunct. + * Note that an MPTCP subflow socket would have SS_NOFDREF set + * by default. So, if it's an MPTCP-subflow we rather check the + * MPTCP-level's socket state for SS_NOFDREF. */ - if (!(so->so_flags & SOF_MP_SUBFLOW) && - (so->so_state & SS_NOFDREF) && - tp->t_state > TCPS_CLOSE_WAIT && tlen) { - tp = tcp_close(tp); - tcpstat.tcps_rcvafterclose++; - rstreason = BANDLIM_UNLIMITED; - IF_TCP_STATINC(ifp, cleanup); - goto dropwithreset; + if (tlen) { + boolean_t close_it = FALSE; + + if (!(so->so_flags & SOF_MP_SUBFLOW) && (so->so_state & SS_NOFDREF) && + tp->t_state > TCPS_CLOSE_WAIT) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "SS_NOFDREF"); + close_it = TRUE; + } + + if ((so->so_flags & SOF_MP_SUBFLOW) && (mptetoso(tptomptp(tp)->mpt_mpte)->so_state & SS_NOFDREF) && + tp->t_state > TCPS_CLOSE_WAIT) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "SOF_MP_SUBFLOW SS_NOFDREF"); + close_it = TRUE; + } + + if ((so->so_flags & SOF_DEFUNCT) && tp->t_state > TCPS_FIN_WAIT_1) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "SOF_DEFUNCT"); + close_it = TRUE; + } + + if (close_it) { + tp = tcp_close(tp); + tcpstat.tcps_rcvafterclose++; + rstreason = BANDLIM_UNLIMITED; + IF_TCP_STATINC(ifp, cleanup); + goto dropwithreset; + } } /* * If segment ends after window, drop trailing data * (and PUSH and FIN); if nothing left, just ACK. */ - todrop = (th->th_seq+tlen) - (tp->rcv_nxt+tp->rcv_wnd); + todrop = (th->th_seq + tlen) - (tp->rcv_nxt + tp->rcv_wnd); if (todrop > 0) { tcpstat.tcps_rcvpackafterwin++; if (todrop >= tlen) { @@ -3159,7 +4248,7 @@ trimthenstep6: SEQ_GT(th->th_seq, tp->rcv_nxt)) { iss = tcp_new_isn(tp); tp = tcp_close(tp); - tcp_unlock(so, 1, 0); + socket_unlock(so, 1); goto findpcb; } /* @@ -3172,26 +4261,28 @@ trimthenstep6: if (tp->rcv_wnd == 0 && th->th_seq == tp->rcv_nxt) { tp->t_flags |= TF_ACKNOW; tcpstat.tcps_rcvwinprobe++; - } else + } else { goto dropafterack; - } else + } + } else { tcpstat.tcps_rcvbyteafterwin += todrop; + } m_adj(m, -todrop); tlen -= todrop; - thflags &= ~(TH_PUSH|TH_FIN); + thflags &= ~(TH_PUSH | TH_FIN); } /* * If last ACK falls within this segment's sequence numbers, * record its timestamp. - * NOTE: + * NOTE: * 1) That the test incorporates suggestions from the latest * proposal of the tcplw@cray.com list (Braden 1993/04/26). * 2) That updating only on newer timestamps interferes with * our earlier PAWS tests, so this check should be solely * predicated on the sequence space of this segment. - * 3) That we modify the segment boundary check to be - * Last.ACK.Sent <= SEG.SEQ + SEG.Len + * 3) That we modify the segment boundary check to be + * Last.ACK.Sent <= SEG.SEQ + SEG.Len * instead of RFC1323's * Last.ACK.Sent < SEG.SEQ + SEG.Len, * This modified check allows us to overcome RFC1323's @@ -3202,21 +4293,40 @@ trimthenstep6: if ((to.to_flags & TOF_TS) != 0 && SEQ_LEQ(th->th_seq, tp->last_ack_sent) && SEQ_LEQ(tp->last_ack_sent, th->th_seq + tlen + - ((thflags & (TH_SYN|TH_FIN)) != 0))) { + ((thflags & (TH_SYN | TH_FIN)) != 0))) { tp->ts_recent_age = tcp_now; tp->ts_recent = to.to_tsval; } /* - * If a SYN is in the window, then this is an + * Stevens: If a SYN is in the window, then this is an * error and we send an RST and drop the connection. + * + * RFC 5961 Section 4.2 + * Send challenge ACK for any SYN in synchronized state + * Perform rate limitation in doing so. */ if (thflags & TH_SYN) { - tp = tcp_drop(tp, ECONNRESET); - rstreason = BANDLIM_UNLIMITED; - postevent(so, 0, EV_RESET); - IF_TCP_STATINC(ifp, synwindow); - goto dropwithreset; + if (tcp_do_rfc5961) { + tcpstat.tcps_badsyn++; + /* Drop if we have reached ACK limit */ + if (tcp_is_ack_ratelimited(tp)) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "rfc5961 bad SYN rate limited"); + goto drop; + } else { + /* Send challenge ACK */ + tcpstat.tcps_synchallenge++; + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "rfc5961 bad SYN challenge ack"); + goto dropafterack; + } + } else { + tp = tcp_drop(tp, ECONNRESET); + rstreason = BANDLIM_UNLIMITED; + postevent(so, 0, EV_RESET); + IF_TCP_STATINC(ifp, synwindow); + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "bad SYN"); + goto dropwithreset; + } } /* @@ -3226,12 +4336,41 @@ trimthenstep6: */ if ((thflags & TH_ACK) == 0) { if (tp->t_state == TCPS_SYN_RECEIVED || - (tp->t_flags & TF_NEEDSYN)) + (tp->t_flags & TF_NEEDSYN)) { + if ((tfo_enabled(tp))) { + /* + * So, we received a valid segment while in + * SYN-RECEIVED (TF_NEEDSYN is actually never + * set, so this is dead code). + * As this cannot be an RST (see that if a bit + * higher), and it does not have the ACK-flag + * set, we want to retransmit the SYN/ACK. + * Thus, we have to reset snd_nxt to snd_una to + * trigger the going back to sending of the + * SYN/ACK. This is more consistent with the + * behavior of tcp_output(), which expects + * to send the segment that is pointed to by + * snd_nxt. + */ + tp->snd_nxt = tp->snd_una; + + /* + * We need to make absolutely sure that we are + * going to reply upon a duplicate SYN-segment. + */ + if (th->th_flags & TH_SYN) { + needoutput = 1; + } + } + goto step6; - else if (tp->t_flags & TF_ACKNOW) + } else if (tp->t_flags & TF_ACKNOW) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "bad ACK"); goto dropafterack; - else + } else { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "bad ACK"); goto drop; + } } /* @@ -3239,7 +4378,6 @@ trimthenstep6: */ switch (tp->t_state) { - /* * In SYN_RECEIVED state, the ack ACKs our SYN, so enter * ESTABLISHED state and continue processing. @@ -3250,11 +4388,11 @@ trimthenstep6: tcpstat.tcps_connects++; /* Do window scaling? */ - if ((tp->t_flags & (TF_RCVD_SCALE|TF_REQ_SCALE)) == - (TF_RCVD_SCALE|TF_REQ_SCALE)) { + if (TCP_WINDOW_SCALE_ENABLED(tp)) { tp->snd_scale = tp->requested_s_scale; tp->rcv_scale = tp->request_r_scale; tp->snd_wnd = th->th_win << tp->snd_scale; + tp->max_sndwnd = tp->snd_wnd; tiwin = tp->snd_wnd; } /* @@ -3265,29 +4403,50 @@ trimthenstep6: tp->t_starttime = tcp_now; tcp_sbrcv_tstmp_check(tp); if (tp->t_flags & TF_NEEDFIN) { - DTRACE_TCP4(state__change, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, int32_t, TCPS_FIN_WAIT_1); + DTRACE_TCP4(state__change, void, NULL, + struct inpcb *, inp, + struct tcpcb *, tp, int32_t, TCPS_FIN_WAIT_1); tp->t_state = TCPS_FIN_WAIT_1; tp->t_flags &= ~TF_NEEDFIN; + + TCP_LOG_CONNECTION_SUMMARY(tp); } else { - DTRACE_TCP4(state__change, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, int32_t, TCPS_ESTABLISHED); + DTRACE_TCP4(state__change, void, NULL, + struct inpcb *, inp, + struct tcpcb *, tp, int32_t, TCPS_ESTABLISHED); tp->t_state = TCPS_ESTABLISHED; tp->t_timer[TCPT_KEEP] = OFFSET_FROM_START(tp, - TCP_CONN_KEEPIDLE(tp)); - if (nstat_collect) - nstat_route_connect_success(tp->t_inpcb->inp_route.ro_rt); + TCP_CONN_KEEPIDLE(tp)); + if (nstat_collect) { + nstat_route_connect_success( + tp->t_inpcb->inp_route.ro_rt); + } + /* + * The SYN is acknowledged but una is not updated + * yet. So pass the value of ack to compute + * sndbytes correctly + */ + inp_count_sndbytes(inp, th->th_ack); } /* * If segment contains data or ACK, will call tcp_reass() * later; if not, do so now to pass queued data to user. */ - if (tlen == 0 && (thflags & TH_FIN) == 0) + if (tlen == 0 && (thflags & TH_FIN) == 0) { + if (isipv6) { + memcpy(&saved_hdr, ip6, sizeof(struct ip6_hdr)); + ip6 = (struct ip6_hdr *)&saved_hdr[0]; + } else { + memcpy(&saved_hdr, ip, ip->ip_hl << 2); + ip = (struct ip *)&saved_hdr[0]; + } + memcpy(&saved_tcphdr, th, sizeof(struct tcphdr)); (void) tcp_reass(tp, (struct tcphdr *)0, &tlen, - NULL, ifp); + NULL, ifp, &read_wakeup); + th = &saved_tcphdr; + } tp->snd_wl1 = th->th_seq - 1; - /* FALLTHROUGH */ #if MPTCP /* * Do not send the connect notification for additional subflows @@ -3298,7 +4457,58 @@ trimthenstep6: isconnected = FALSE; } else #endif /* MPTCP */ - isconnected = TRUE; + isconnected = TRUE; + if ((tp->t_tfo_flags & TFO_F_COOKIE_VALID)) { + /* Done this when receiving the SYN */ + isconnected = FALSE; + + OSDecrementAtomic(&tcp_tfo_halfcnt); + + /* Panic if something has gone terribly wrong. */ + VERIFY(tcp_tfo_halfcnt >= 0); + + tp->t_tfo_flags &= ~TFO_F_COOKIE_VALID; + } + + /* + * In case there is data in the send-queue (e.g., TFO is being + * used, or connectx+data has been done), then if we would + * "FALLTHROUGH", we would handle this ACK as if data has been + * acknowledged. But, we have to prevent this. And this + * can be prevented by increasing snd_una by 1, so that the + * SYN is not considered as data (snd_una++ is actually also + * done in SYN_SENT-state as part of the regular TCP stack). + * + * In case there is data on this ack as well, the data will be + * handled by the label "dodata" right after step6. + */ + if (so->so_snd.sb_cc) { + tp->snd_una++; /* SYN is acked */ + if (SEQ_LT(tp->snd_nxt, tp->snd_una)) { + tp->snd_nxt = tp->snd_una; + } + + /* + * No duplicate-ACK handling is needed. So, we + * directly advance to processing the ACK (aka, + * updating the RTT estimation,...) + * + * But, we first need to handle eventual SACKs, + * because TFO will start sending data with the + * SYN/ACK, so it might be that the client + * includes a SACK with its ACK. + */ + if (SACK_ENABLED(tp) && + (to.to_nsacks > 0 || + !TAILQ_EMPTY(&tp->snd_holes))) { + tcp_sack_doack(tp, &to, th, + &sack_bytes_acked); + } + + goto process_ACK; + } + + /* FALLTHROUGH */ /* * In ESTABLISHED state: drop duplicate ACKs; ACK out of range @@ -3317,21 +4527,43 @@ trimthenstep6: case TCPS_TIME_WAIT: if (SEQ_GT(th->th_ack, tp->snd_max)) { tcpstat.tcps_rcvacktoomuch++; - goto dropafterack; + if (tcp_do_rfc5961 && tcp_is_ack_ratelimited(tp)) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "rfc5961 rcvacktoomuch"); + goto drop; + } else { + goto dropafterack; + } + } + if (tcp_do_rfc5961 && SEQ_LT(th->th_ack, tp->snd_una - tp->max_sndwnd)) { + if (tcp_is_ack_ratelimited(tp)) { + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "rfc5961 bad ACK"); + goto drop; + } else { + goto dropafterack; + } } + if (SACK_ENABLED(tp) && to.to_nsacks > 0) { + recvd_dsack = tcp_sack_process_dsack(tp, &to, th); + /* + * If DSACK is received and this packet has no + * other SACK information, it can be dropped. + * We do not want to treat it as a duplicate ack. + */ + if (recvd_dsack && + SEQ_LEQ(th->th_ack, tp->snd_una) && + to.to_nsacks == 0) { + tcp_bad_rexmt_check(tp, th, &to); + goto drop; + } + } + if (SACK_ENABLED(tp) && - (to.to_nsacks > 0 || !TAILQ_EMPTY(&tp->snd_holes))) - tcp_sack_doack(tp, &to, th->th_ack, &sack_bytes_acked); + (to.to_nsacks > 0 || !TAILQ_EMPTY(&tp->snd_holes))) { + tcp_sack_doack(tp, &to, th, &sack_bytes_acked); + } + #if MPTCP - if ((tp->t_mpuna) && (SEQ_GEQ(th->th_ack, tp->t_mpuna))) { -#if 0 - if ((tp->t_mpflags & TMPF_MPTCP_TRUE) && - !(tp->t_mpflags & TMPF_MPTCP_READY)) { - printf("%s: fallback? %x %x \n", __func__, - th->th_ack, tp->t_mpuna); - tp->t_mpuna = 0; - } -#endif + if (tp->t_mpuna && SEQ_GEQ(th->th_ack, tp->t_mpuna)) { if (tp->t_mpflags & TMPF_PREESTABLISHED) { /* MP TCP establishment succeeded */ tp->t_mpuna = 0; @@ -3341,10 +4573,7 @@ trimthenstep6: ~TMPF_PREESTABLISHED; tp->t_mpflags |= TMPF_MPTCP_TRUE; - so->so_flags |= SOF_MPTCP_TRUE; - if (mptcp_dbg >= MP_ERR_DEBUG) - printf("MPTCP SUCCESS" - "%s \n",__func__); + tp->t_timer[TCPT_JACK_RXMT] = 0; tp->t_mprxtshift = 0; isconnected = TRUE; @@ -3353,20 +4582,36 @@ trimthenstep6: } } else { isconnected = TRUE; - tp->t_mpflags &= ~TMPF_SENT_KEYS; - } } } #endif /* MPTCP */ + + tcp_tfo_rcv_ack(tp, th); + /* * If we have outstanding data (other than * a window probe), this is a completely - * duplicate ack (ie, window info didn't - * change) and the ack is the biggest we've seen. - */ + * duplicate ack and the ack is the biggest we've seen. + * + * Need to accommodate a change in window on duplicate acks + * to allow operating systems that update window during + * recovery with SACK + */ if (SEQ_LEQ(th->th_ack, tp->snd_una)) { - if (tlen == 0 && tiwin == tp->snd_wnd) { + if (tlen == 0 && (tiwin == tp->snd_wnd || + (to.to_nsacks > 0 && sack_bytes_acked > 0))) { + /* + * If both ends send FIN at the same time, + * then the ack will be a duplicate ack + * but we have to process the FIN. Check + * for this condition and process the FIN + * instead of the dupack + */ + if ((thflags & TH_FIN) && + !TCPS_HAVERCVDFIN(tp->t_state)) { + break; + } process_dupack: #if MPTCP /* @@ -3376,97 +4621,51 @@ process_dupack: if (to.to_flags & TOF_MPTCP) { goto drop; } + + if ((isconnected) && (tp->t_mpflags & TMPF_JOINED_FLOW)) { + mptcplog((LOG_DEBUG, "MPTCP " + "Sockets: bypass ack recovery\n"), + MPTCP_SOCKET_DBG, + MPTCP_LOGLVL_VERBOSE); + break; + } #endif /* MPTCP */ + /* + * If a duplicate acknowledgement was seen + * after ECN, it indicates packet loss in + * addition to ECN. Reset INRECOVERY flag + * so that we can process partial acks + * correctly + */ + if (tp->ecn_flags & TE_INRECOVERY) { + tp->ecn_flags &= ~TE_INRECOVERY; + } + tcpstat.tcps_rcvdupack++; ++tp->t_dupacks; - /* - * Check if we need to reset the limit on early - * retransmit + + /* + * Check if we need to reset the limit on + * early retransmit */ - if (TSTMP_GEQ(tcp_now, - (tp->t_early_rexmt_win + TCP_EARLY_REXMT_WIN))) + if (tp->t_early_rexmt_count > 0 && + TSTMP_GEQ(tcp_now, + (tp->t_early_rexmt_win + + TCP_EARLY_REXMT_WIN))) { tp->t_early_rexmt_count = 0; + } - /* + /* * Is early retransmit needed? We check for * this when the connection is waiting for - * more duplicate acks to enter fast recovery. + * duplicate acks to enter fast recovery. */ - if (early_rexmt && - tp->t_early_rexmt_count < TCP_EARLY_REXMT_LIMIT && - !IN_FASTRECOVERY(tp) && - SEQ_GT(tp->snd_max, tp->snd_una) && - (tp->t_dupacks == 1 || - (SACK_ENABLED(tp) && - !TAILQ_EMPTY(&tp->snd_holes)))) { - /* - * If there are only a few outstanding - * segments on the connection, we might need - * to lower the retransmit threshold. This - * will allow us to do Early Retransmit as - * described in RFC 5827. - */ - u_int32_t obytes, snd_off; - int32_t snd_len; - if (SACK_ENABLED(tp) && - !TAILQ_EMPTY(&tp->snd_holes)) { - obytes = (tp->snd_max - tp->snd_fack) + - tp->sackhint.sack_bytes_rexmit; - } else { - obytes = (tp->snd_max - tp->snd_una); - } - - /* In order to lower retransmit threshold the - * following two conditions must be met. - * 1. the amount of outstanding data is less - * than 4*SMSS bytes - * 2. there is no unsent data ready for - * transmission or the advertised window - * will limit sending new segments. - */ - snd_off = tp->snd_max - tp->snd_una; - snd_len = min(so->so_snd.sb_cc, tp->snd_wnd) - snd_off; - if (obytes < (tp->t_maxseg << 2) && - snd_len <= 0) { - u_int32_t osegs; - - - osegs = obytes / tp->t_maxseg; - if ((osegs * tp->t_maxseg) < obytes) - osegs++; - - /* - * Since the connection might have already - * received some dupacks, we add them to - * to the outstanding segments count to get - * the correct retransmit threshold. - * - * By checking for early retransmit after - * receiving some duplicate acks when SACK - * is supported, the connection will be able - * to enter fast recovery even if multiple - * segments are lost in the same window. - */ - osegs += tp->t_dupacks; - if (osegs < 4) { - tcpstat.tcps_early_rexmt++; - tp->t_rexmtthresh = ((osegs - 1) > 1) ? - (osegs - 1) : 1; - tp->t_rexmtthresh = min(tp->t_rexmtthresh, - tcprexmtthresh); - tp->t_rexmtthresh = max(tp->t_rexmtthresh, - tp->t_dupacks); - DTRACE_TCP5(cc, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, struct tcphdr *, th, - int32_t, TCP_CC_EARLY_RETRANSMIT); - if (tp->t_early_rexmt_count == 0) - tp->t_early_rexmt_win = tcp_now; - tp->t_early_rexmt_count++; - } - } + if (!IN_FASTRECOVERY(tp)) { + tcp_early_rexmt_check(tp, th); } + /* - * If we've seen exactly our rexmt threshold + * If we've seen exactly rexmt threshold * of duplicate acks, assume a packet * has been dropped and retransmit it. * Kludge snd_nxt & the congestion @@ -3486,35 +4685,61 @@ process_dupack: * network. */ if (tp->t_timer[TCPT_REXMT] == 0 || - (th->th_ack != tp->snd_una && sack_bytes_acked == 0)) { + (th->th_ack != tp->snd_una + && sack_bytes_acked == 0)) { tp->t_dupacks = 0; tp->t_rexmtthresh = tcprexmtthresh; } else if (tp->t_dupacks > tp->t_rexmtthresh || - IN_FASTRECOVERY(tp)) { - if (SACK_ENABLED(tp) && IN_FASTRECOVERY(tp)) { + IN_FASTRECOVERY(tp)) { + /* + * If this connection was seeing packet + * reordering, then recovery might be + * delayed to disambiguate between + * reordering and loss + */ + if (SACK_ENABLED(tp) && !IN_FASTRECOVERY(tp) && + (tp->t_flagsext & + (TF_PKTS_REORDERED | TF_DELAY_RECOVERY)) == + (TF_PKTS_REORDERED | TF_DELAY_RECOVERY)) { + /* + * Since the SACK information is already + * updated, this ACK will be dropped + */ + break; + } + + if (SACK_ENABLED(tp) + && IN_FASTRECOVERY(tp)) { int awnd; - + /* * Compute the amount of data in flight first. - * We can inject new data into the pipe iff - * we have less than 1/2 the original window's + * We can inject new data into the pipe iff + * we have less than 1/2 the original window's * worth of data in flight. */ awnd = (tp->snd_nxt - tp->snd_fack) + - tp->sackhint.sack_bytes_rexmit; + tp->sackhint.sack_bytes_rexmit; if (awnd < tp->snd_ssthresh) { tp->snd_cwnd += tp->t_maxseg; - if (tp->snd_cwnd > tp->snd_ssthresh) + if (tp->snd_cwnd > tp->snd_ssthresh) { tp->snd_cwnd = tp->snd_ssthresh; + } } - } else + } else { tp->snd_cwnd += tp->t_maxseg; + } - DTRACE_TCP5(cc, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, struct tcphdr *, th, - int32_t, TCP_CC_IN_FASTRECOVERY); + /* Process any window updates */ + if (tiwin > tp->snd_wnd) { + tcp_update_window(tp, thflags, + th, tiwin, tlen); + } + tcp_ccdbg_trace(tp, th, + TCP_CC_IN_FASTRECOVERY); (void) tcp_output(tp); + goto drop; } else if (tp->t_dupacks == tp->t_rexmtthresh) { tcp_seq onxt = tp->snd_nxt; @@ -3530,6 +4755,8 @@ process_dupack: if (IN_FASTRECOVERY(tp)) { tp->t_dupacks = 0; break; + } else if (tp->t_flagsext & TF_DELAY_RECOVERY) { + break; } } else { if (SEQ_LEQ(th->th_ack, @@ -3538,48 +4765,101 @@ process_dupack: break; } } - + if (tp->t_flags & TF_SENTFIN) { + tp->snd_recover = tp->snd_max - 1; + } else { + tp->snd_recover = tp->snd_max; + } + tp->t_timer[TCPT_PTO] = 0; + tp->t_rtttime = 0; + + /* + * If the connection has seen pkt + * reordering, delay recovery until + * it is clear that the packet + * was lost. + */ + if (SACK_ENABLED(tp) && + (tp->t_flagsext & + (TF_PKTS_REORDERED | TF_DELAY_RECOVERY)) + == TF_PKTS_REORDERED && + !IN_FASTRECOVERY(tp) && + tp->t_reorderwin > 0 && + (tp->t_state == TCPS_ESTABLISHED || + tp->t_state == TCPS_FIN_WAIT_1)) { + tp->t_timer[TCPT_DELAYFR] = + OFFSET_FROM_START(tp, + tp->t_reorderwin); + tp->t_flagsext |= TF_DELAY_RECOVERY; + tcpstat.tcps_delay_recovery++; + tcp_ccdbg_trace(tp, th, + TCP_CC_DELAY_FASTRECOVERY); + break; + } + + tcp_rexmt_save_state(tp); /* - * If the current tcp cc module has + * If the current tcp cc module has * defined a hook for tasks to run * before entering FR, call it */ - if (CC_ALGO(tp)->pre_fr != NULL) + if (CC_ALGO(tp)->pre_fr != NULL) { CC_ALGO(tp)->pre_fr(tp); + } ENTER_FASTRECOVERY(tp); - tp->snd_recover = tp->snd_max; tp->t_timer[TCPT_REXMT] = 0; - tp->t_rtttime = 0; - if ((tp->ecn_flags & TE_ECN_ON) == TE_ECN_ON) { + if (TCP_ECN_ENABLED(tp)) { tp->ecn_flags |= TE_SENDCWR; } + if (SACK_ENABLED(tp)) { tcpstat.tcps_sack_recovery_episode++; + tp->t_sack_recovery_episode++; tp->sack_newdata = tp->snd_nxt; tp->snd_cwnd = tp->t_maxseg; + tp->t_flagsext &= + ~TF_CWND_NONVALIDATED; + + /* Process any window updates */ + if (tiwin > tp->snd_wnd) { + tcp_update_window( + tp, thflags, + th, tiwin, tlen); + } - DTRACE_TCP5(cc, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, struct tcphdr *, th, - int32_t, TCP_CC_ENTER_FASTRECOVERY); - + tcp_ccdbg_trace(tp, th, + TCP_CC_ENTER_FASTRECOVERY); (void) tcp_output(tp); goto drop; } tp->snd_nxt = th->th_ack; tp->snd_cwnd = tp->t_maxseg; + + /* Process any window updates */ + if (tiwin > tp->snd_wnd) { + tcp_update_window(tp, + thflags, + th, tiwin, tlen); + } + (void) tcp_output(tp); - tp->snd_cwnd = tp->snd_ssthresh + - tp->t_maxseg * tp->t_dupacks; - if (SEQ_GT(onxt, tp->snd_nxt)) + if (tp->t_flagsext & TF_CWND_NONVALIDATED) { + tcp_cc_adjust_nonvalidated_cwnd(tp); + } else { + tp->snd_cwnd = tp->snd_ssthresh + + tp->t_maxseg * tp->t_dupacks; + } + if (SEQ_GT(onxt, tp->snd_nxt)) { tp->snd_nxt = onxt; - DTRACE_TCP5(cc, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, struct tcphdr *, th, - int32_t, TCP_CC_ENTER_FASTRECOVERY); + } + + tcp_ccdbg_trace(tp, th, + TCP_CC_ENTER_FASTRECOVERY); goto drop; - } else if (limited_txmt && - ALLOW_LIMITED_TRANSMIT(tp) && - (!(SACK_ENABLED(tp)) || sack_bytes_acked > 0) && - (so->so_snd.sb_cc - (tp->snd_max - tp->snd_una)) > 0) { + } else if (limited_txmt && + ALLOW_LIMITED_TRANSMIT(tp) && + (!(SACK_ENABLED(tp)) || sack_bytes_acked > 0) && + (so->so_snd.sb_cc - (tp->snd_max - tp->snd_una)) > 0) { u_int32_t incr = (tp->t_maxseg * tp->t_dupacks); /* Use Limited Transmit algorithm on the first two @@ -3589,16 +4869,11 @@ process_dupack: tcpstat.tcps_limited_txt++; (void) tcp_output(tp); - DTRACE_TCP5(cc, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, struct tcphdr *, th, - int32_t, TCP_CC_LIMITED_TRANSMIT); - + tcp_ccdbg_trace(tp, th, TCP_CC_LIMITED_TRANSMIT); + /* Reset snd_cwnd back to normal */ tp->snd_cwnd -= incr; } - } else { - tp->t_dupacks = 0; - tp->t_rexmtthresh = tcprexmtthresh; } break; } @@ -3608,26 +4883,54 @@ process_dupack: */ if (IN_FASTRECOVERY(tp)) { if (SEQ_LT(th->th_ack, tp->snd_recover)) { - if (SACK_ENABLED(tp)) + /* + * If we received an ECE and entered + * recovery, the subsequent ACKs should + * not be treated as partial acks. + */ + if (tp->ecn_flags & TE_INRECOVERY) { + goto process_ACK; + } + + if (SACK_ENABLED(tp)) { tcp_sack_partialack(tp, th); - else - tcp_newreno_partial_ack(tp, th); - - DTRACE_TCP5(cc, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, struct tcphdr *, th, - int32_t, TCP_CC_PARTIAL_ACK); + } else { + tcp_newreno_partial_ack(tp, th); + } + tcp_ccdbg_trace(tp, th, TCP_CC_PARTIAL_ACK); } else { EXIT_FASTRECOVERY(tp); - if (CC_ALGO(tp)->post_fr != NULL) + if (CC_ALGO(tp)->post_fr != NULL) { CC_ALGO(tp)->post_fr(tp, th); - DTRACE_TCP5(cc, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, struct tcphdr *, th, - int32_t, TCP_CC_EXIT_FASTRECOVERY); + } + tp->t_pipeack = 0; + tcp_clear_pipeack_state(tp); + tcp_ccdbg_trace(tp, th, + TCP_CC_EXIT_FASTRECOVERY); + } + } else if ((tp->t_flagsext & + (TF_PKTS_REORDERED | TF_DELAY_RECOVERY)) + == (TF_PKTS_REORDERED | TF_DELAY_RECOVERY)) { + /* + * If the ack acknowledges upto snd_recover or if + * it acknowledges all the snd holes, exit + * recovery and cancel the timer. Otherwise, + * this is a partial ack. Wait for recovery timer + * to enter recovery. The snd_holes have already + * been updated. + */ + if (SEQ_GEQ(th->th_ack, tp->snd_recover) || + TAILQ_EMPTY(&tp->snd_holes)) { + tp->t_timer[TCPT_DELAYFR] = 0; + tp->t_flagsext &= ~TF_DELAY_RECOVERY; + EXIT_FASTRECOVERY(tp); + tcp_ccdbg_trace(tp, th, + TCP_CC_EXIT_FASTRECOVERY); } } else { /* - * We were not in fast recovery. Reset the duplicate ack - * counter. + * We were not in fast recovery. Reset the + * duplicate ack counter. */ tp->t_dupacks = 0; tp->t_rexmtthresh = tcprexmtthresh; @@ -3649,14 +4952,14 @@ process_dupack: tp->t_flags &= ~TF_NEEDSYN; tp->snd_una++; /* Do window scaling? */ - if ((tp->t_flags & (TF_RCVD_SCALE|TF_REQ_SCALE)) == - (TF_RCVD_SCALE|TF_REQ_SCALE)) { + if (TCP_WINDOW_SCALE_ENABLED(tp)) { tp->snd_scale = tp->requested_s_scale; tp->rcv_scale = tp->request_r_scale; } } process_ACK: + VERIFY(SEQ_GEQ(th->th_ack, tp->snd_una)); acked = BYTES_ACKED(th, tp); tcpstat.tcps_rcvackpack++; tcpstat.tcps_rcvackbyte += acked; @@ -3665,19 +4968,11 @@ process_ACK: * If the last packet was a retransmit, make sure * it was not spurious. * - * If the ack has ECE bit set, skip bad - * retransmit recovery. + * This will also take care of congestion window + * adjustment if a last packet was recovered due to a + * tail loss probe. */ - if (tp->t_rxtshift > 0 && - (thflags & TH_ECE) == 0 && - tcp_detect_bad_rexmt(tp, &to)) { - ++tcpstat.tcps_sndrexmitbad; - tcp_bad_rexmt_restore_state(tp, th); - - DTRACE_TCP5(cc, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, struct tcphdr *, th, - int32_t, TCP_CC_BAD_REXMT_RECOVERY); - } + tcp_bad_rexmt_check(tp, th, &to); /* Recalculate the RTT */ tcp_compute_rtt(tp, &to, th); @@ -3688,30 +4983,64 @@ process_ACK: * If there is more data to be acked, restart retransmit * timer, using current (possibly backed-off) value. */ + TCP_RESET_REXMT_STATE(tp); + TCPT_RANGESET(tp->t_rxtcur, TCP_REXMTVAL(tp), + tp->t_rttmin, TCPTV_REXMTMAX, + TCP_ADD_REXMTSLOP(tp)); if (th->th_ack == tp->snd_max) { tp->t_timer[TCPT_REXMT] = 0; + tp->t_timer[TCPT_PTO] = 0; needoutput = 1; - } else if (tp->t_timer[TCPT_PERSIST] == 0) - tp->t_timer[TCPT_REXMT] = OFFSET_FROM_START(tp, tp->t_rxtcur); + } else if (tp->t_timer[TCPT_PERSIST] == 0) { + tp->t_timer[TCPT_REXMT] = OFFSET_FROM_START(tp, + tp->t_rxtcur); + } + + if ((prev_t_state == TCPS_SYN_SENT || + prev_t_state == TCPS_SYN_RECEIVED) && + tp->t_state == TCPS_ESTABLISHED) { + TCP_LOG_RTT_INFO(tp); + } /* - * If no data (only SYN) was ACK'd, - * skip rest of ACK processing. + * If no data (only SYN) was ACK'd, skip rest of ACK + * processing. */ - if (acked == 0) + if (acked == 0) { goto step6; + } + + /* + * When outgoing data has been acked (except the SYN+data), we + * mark this connection as "sending good" for TFO. + */ + if ((tp->t_tfo_stats & TFO_S_SYN_DATA_SENT) && + !(tp->t_tfo_flags & TFO_F_NO_SNDPROBING) && + !(th->th_flags & TH_SYN)) { + tp->t_tfo_flags |= TFO_F_NO_SNDPROBING; + } - if ((thflags & TH_ECE) != 0 && - ((tp->ecn_flags & TE_ECN_ON) == TE_ECN_ON)) { + /* + * If TH_ECE is received, make sure that ECN is enabled + * on that connection and we have sent ECT on data packets. + */ + if ((thflags & TH_ECE) != 0 && TCP_ECN_ENABLED(tp) && + (tp->ecn_flags & TE_SENDIPECT)) { /* - * Reduce the congestion window if we haven't done so. + * Reduce the congestion window if we haven't + * done so. */ - if (!SACK_ENABLED(tp) && !IN_FASTRECOVERY(tp) && - SEQ_GEQ(th->th_ack, tp->snd_recover)) { + if (!IN_FASTRECOVERY(tp)) { tcp_reduce_congestion_window(tp); - DTRACE_TCP5(cc, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, struct tcphdr *, th, - int32_t, TCP_CC_ECN_RCVD); + tp->ecn_flags |= (TE_INRECOVERY | TE_SENDCWR); + /* + * Also note that the connection received + * ECE atleast once + */ + tp->ecn_flags |= TE_RECV_ECN_ECE; + INP_INC_IFNET_STAT(inp, ecn_recv_ece); + tcpstat.tcps_ecn_recv_ece++; + tcp_ccdbg_trace(tp, th, TCP_CC_ECN_RCVD); } } @@ -3724,60 +5053,68 @@ process_ACK: * not updated yet. */ if (!IN_FASTRECOVERY(tp)) { - if (CC_ALGO(tp)->ack_rcvd != NULL) + if (CC_ALGO(tp)->ack_rcvd != NULL) { CC_ALGO(tp)->ack_rcvd(tp, th); - - DTRACE_TCP5(cc, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, struct tcphdr *, th, - int32_t, TCP_CC_ACK_RCVD); + } + tcp_ccdbg_trace(tp, th, TCP_CC_ACK_RCVD); } if (acked > so->so_snd.sb_cc) { tp->snd_wnd -= so->so_snd.sb_cc; sbdrop(&so->so_snd, (int)so->so_snd.sb_cc); if (so->so_flags & SOF_ENABLE_MSGS) { - so->so_msg_state->msg_serial_bytes -= - (int)so->so_snd.sb_cc; + so->so_msg_state->msg_serial_bytes -= + (int)so->so_snd.sb_cc; } ourfinisacked = 1; } else { sbdrop(&so->so_snd, acked); if (so->so_flags & SOF_ENABLE_MSGS) { - so->so_msg_state->msg_serial_bytes -= - acked; + so->so_msg_state->msg_serial_bytes -= + acked; } tcp_sbsnd_trim(&so->so_snd); tp->snd_wnd -= acked; ourfinisacked = 0; } /* detect una wraparound */ - if ( !IN_FASTRECOVERY(tp) && + if (!IN_FASTRECOVERY(tp) && SEQ_GT(tp->snd_una, tp->snd_recover) && - SEQ_LEQ(th->th_ack, tp->snd_recover)) + SEQ_LEQ(th->th_ack, tp->snd_recover)) { tp->snd_recover = th->th_ack - 1; + } if (IN_FASTRECOVERY(tp) && - SEQ_GEQ(th->th_ack, tp->snd_recover)) + SEQ_GEQ(th->th_ack, tp->snd_recover)) { EXIT_FASTRECOVERY(tp); + } tp->snd_una = th->th_ack; + if (SACK_ENABLED(tp)) { - if (SEQ_GT(tp->snd_una, tp->snd_recover)) + if (SEQ_GT(tp->snd_una, tp->snd_recover)) { tp->snd_recover = tp->snd_una; + } } - if (SEQ_LT(tp->snd_nxt, tp->snd_una)) + if (SEQ_LT(tp->snd_nxt, tp->snd_una)) { tp->snd_nxt = tp->snd_una; + } + if (!SLIST_EMPTY(&tp->t_rxt_segments) && + !TCP_DSACK_SEQ_IN_WINDOW(tp, tp->t_dsack_lastuna, + tp->snd_una)) { + tcp_rxtseg_clean(tp); + } if ((tp->t_flagsext & TF_MEASURESNDBW) != 0 && - tp->t_bwmeas != NULL) + tp->t_bwmeas != NULL) { tcp_bwmeas_check(tp); + } - /* - * sowwakeup must happen after snd_una, et al. are updated so that - * the sequence numbers are in sync with so_snd - */ - sowwakeup(so); + write_wakeup = 1; - switch (tp->t_state) { + if (!SLIST_EMPTY(&tp->t_notify_ack)) { + tcp_notify_acknowledgement(tp, so); + } + switch (tp->t_state) { /* * In FIN_WAIT_1 STATE in addition to the processing * for the ESTABLISHED state if our FIN is now acknowledged @@ -3794,23 +5131,22 @@ process_ACK: */ if (so->so_state & SS_CANTRCVMORE) { tp->t_timer[TCPT_2MSL] = OFFSET_FROM_START(tp, - TCP_CONN_MAXIDLE(tp)); + TCP_CONN_MAXIDLE(tp)); isconnected = FALSE; isdisconnected = TRUE; } - DTRACE_TCP4(state__change, void, NULL, - struct inpcb *, inp, - struct tcpcb *, tp, - int32_t, TCPS_FIN_WAIT_2); + DTRACE_TCP4(state__change, void, NULL, + struct inpcb *, inp, + struct tcpcb *, tp, + int32_t, TCPS_FIN_WAIT_2); tp->t_state = TCPS_FIN_WAIT_2; - /* fall through and make sure we also recognize - * data ACKed with the FIN + /* fall through and make sure we also recognize + * data ACKed with the FIN */ } - tp->t_flags |= TF_ACKNOW; break; - /* + /* * In CLOSING STATE in addition to the processing for * the ESTABLISHED state if the ACK acknowledges our FIN * then enter the TIME-WAIT state, otherwise ignore @@ -3818,17 +5154,20 @@ process_ACK: */ case TCPS_CLOSING: if (ourfinisacked) { - DTRACE_TCP4(state__change, void, NULL, - struct inpcb *, inp, - struct tcpcb *, tp, - int32_t, TCPS_TIME_WAIT); + DTRACE_TCP4(state__change, void, NULL, + struct inpcb *, inp, + struct tcpcb *, tp, + int32_t, TCPS_TIME_WAIT); tp->t_state = TCPS_TIME_WAIT; tcp_canceltimers(tp); - add_to_time_wait(tp, 2 * tcp_msl); + if (tp->t_flagsext & TF_NOTIMEWAIT) { + tp->t_flags |= TF_CLOSING; + } else { + add_to_time_wait(tp, 2 * tcp_msl); + } isconnected = FALSE; isdisconnected = TRUE; } - tp->t_flags |= TF_ACKNOW; break; /* @@ -3855,21 +5194,21 @@ process_ACK: } /* - * If there is a SACK option on the ACK and we + * If there is a SACK option on the ACK and we * haven't seen any duplicate acks before, count * it as a duplicate ack even if the cumulative * ack is advanced. If the receiver delayed an * ack and detected loss afterwards, then the ack - * will advance cumulative ack and will also have + * will advance cumulative ack and will also have * a SACK option. So counting it as one duplicate * ack is ok. - */ + */ if (sack_ackadv == 1 && - tp->t_state == TCPS_ESTABLISHED && - SACK_ENABLED(tp) && - sack_bytes_acked > 0 && - tp->t_dupacks == 0 && - SEQ_LEQ(th->th_ack, tp->snd_una) && tlen == 0) { + tp->t_state == TCPS_ESTABLISHED && + SACK_ENABLED(tp) && sack_bytes_acked > 0 && + to.to_nsacks > 0 && tp->t_dupacks == 0 && + SEQ_LEQ(th->th_ack, tp->snd_una) && tlen == 0 && + !(tp->t_flagsext & TF_PKTS_REORDERED)) { tcpstat.tcps_sack_ackadv++; goto process_dupack; } @@ -3878,21 +5217,8 @@ process_ACK: step6: /* * Update window information. - * Don't look at window if no ACK: TAC's send garbage on first SYN. */ - if ((thflags & TH_ACK) && - (SEQ_LT(tp->snd_wl1, th->th_seq) || - (tp->snd_wl1 == th->th_seq && (SEQ_LT(tp->snd_wl2, th->th_ack) || - (tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd))))) { - /* keep track of pure window updates */ - if (tlen == 0 && - tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd) - tcpstat.tcps_rcvwinupd++; - tp->snd_wnd = tiwin; - tp->snd_wl1 = th->th_seq; - tp->snd_wl2 = th->th_ack; - if (tp->snd_wnd > tp->max_sndwnd) - tp->max_sndwnd = tp->snd_wnd; + if (tcp_update_window(tp, thflags, th, tiwin, tlen)) { needoutput = 1; } @@ -3908,9 +5234,9 @@ step6: * actually wanting to send this much urgent data. */ if (th->th_urp + so->so_rcv.sb_cc > sb_max) { - th->th_urp = 0; /* XXX */ - thflags &= ~TH_URG; /* XXX */ - goto dodata; /* XXX */ + th->th_urp = 0; /* XXX */ + thflags &= ~TH_URG; /* XXX */ + goto dodata; /* XXX */ } /* * If this segment advances the known urgent pointer, @@ -3926,7 +5252,7 @@ step6: * of data past the urgent section as the original * spec states (in one of two places). */ - if (SEQ_GT(th->th_seq+th->th_urp, tp->rcv_up)) { + if (SEQ_GT(th->th_seq + th->th_urp, tp->rcv_up)) { tp->rcv_up = th->th_seq + th->th_urp; so->so_oobmark = so->so_rcv.sb_cc + (tp->rcv_up - tp->rcv_nxt) - 1; @@ -3945,19 +5271,21 @@ step6: */ if (th->th_urp <= (u_int32_t)tlen #if SO_OOBINLINE - && (so->so_options & SO_OOBINLINE) == 0 + && (so->so_options & SO_OOBINLINE) == 0 #endif - ) + ) { tcp_pulloutofband(so, th, m, - drop_hdrlen); /* hdr drop is delayed */ + drop_hdrlen); /* hdr drop is delayed */ + } } else { /* * If no out of band data is expected, * pull receive urgent pointer along * with the receive window. */ - if (SEQ_GT(tp->rcv_nxt, tp->rcv_up)) + if (SEQ_GT(tp->rcv_nxt, tp->rcv_up)) { tp->rcv_up = tp->rcv_nxt; + } } dodata: @@ -3971,14 +5299,15 @@ dodata: soisdisconnected(so); } - /* Let's check the state of pcb just to make sure that it did not get closed + /* Let's check the state of pcb just to make sure that it did not get closed * when we unlocked above */ if (inp->inp_state == INPCB_STATE_DEAD) { /* Just drop the packet that we are processing and return */ + TCP_LOG_DROP_PCB(TCP_LOG_HDR, th, tp, false, "INPCB_STATE_DEAD"); goto drop; } - + /* * Process the segment text, merging it into the TCP sequencing queue, * and arranging for acknowledgment of receipt if necessary. @@ -3986,12 +5315,18 @@ dodata: * is presented to the user (this happens in tcp_usrreq.c, * case PRU_RCVD). If a FIN has already been received on this * connection then we just ignore the text. + * + * If we are in SYN-received state and got a valid TFO cookie, we want + * to process the data. */ if ((tlen || (thflags & TH_FIN)) && - TCPS_HAVERCVDFIN(tp->t_state) == 0) { + TCPS_HAVERCVDFIN(tp->t_state) == 0 && + (TCPS_HAVEESTABLISHED(tp->t_state) || + (tp->t_state == TCPS_SYN_RECEIVED && + (tp->t_tfo_flags & TFO_F_COOKIE_VALID)))) { tcp_seq save_start = th->th_seq; tcp_seq save_end = th->th_seq + tlen; - m_adj(m, drop_hdrlen); /* delayed header drop */ + m_adj(m, drop_hdrlen); /* delayed header drop */ /* * Insert segment which includes th into TCP reassembly queue * with control block tp. Set thflags to whether reassembly now @@ -4004,28 +5339,25 @@ dodata: * immediately when segments are out of order (so * fast retransmit can work). */ - if (th->th_seq == tp->rcv_nxt && - LIST_EMPTY(&tp->t_segq) && - TCPS_HAVEESTABLISHED(tp->t_state)) { + if (th->th_seq == tp->rcv_nxt && LIST_EMPTY(&tp->t_segq)) { TCP_INC_VAR(tp->t_unacksegs, nlropkts); /* - * Calculate the RTT on the receiver only if the - * connection is in streaming mode and the last + * Calculate the RTT on the receiver only if the + * connection is in streaming mode and the last * packet was not an end-of-write */ - if ((tp->t_flags & TF_STRETCHACK) && - !(tp->t_flagsext & TF_STREAMEOW)) + if (tp->t_flags & TF_STREAMING_ON) { tcp_compute_rtt(tp, &to, th); - - if (DELAY_ACK(tp, th) && - ((tp->t_flags & TF_ACKNOW) == 0) ) { + } + + if (DELAY_ACK(tp, th) && + ((tp->t_flags & TF_ACKNOW) == 0)) { if ((tp->t_flags & TF_DELACK) == 0) { tp->t_flags |= TF_DELACK; - tp->t_timer[TCPT_DELACK] = - OFFSET_FROM_START(tp, tcp_delack); + tp->t_timer[TCPT_DELACK] = + OFFSET_FROM_START(tp, tcp_delack); } - } - else { + } else { tp->t_flags |= TF_ACKNOW; } tp->rcv_nxt += tlen; @@ -4034,49 +5366,84 @@ dodata: tcpstat.tcps_rcvbyte += tlen; if (nstat_collect) { if (m->m_pkthdr.pkt_flags & PKTF_SW_LRO_PKT) { - INP_ADD_STAT(inp, cell, wifi, rxpackets, - m->m_pkthdr.lro_npkts); + INP_ADD_STAT(inp, cell, wifi, wired, + rxpackets, m->m_pkthdr.lro_npkts); } else { - INP_ADD_STAT(inp, cell, wifi, rxpackets, 1); + INP_ADD_STAT(inp, cell, wifi, wired, + rxpackets, 1); } - INP_ADD_STAT(inp, cell, wifi, rxbytes, tlen); + INP_ADD_STAT(inp, cell, wifi, wired, + rxbytes, tlen); + inp_set_activity_bitmap(inp); } - tcp_sbrcv_grow(tp, &so->so_rcv, &to, tlen); + tcp_sbrcv_grow(tp, &so->so_rcv, &to, tlen, + TCP_AUTORCVBUF_MAX(ifp)); so_recv_data_stat(so, m, drop_hdrlen); - + + if (isipv6) { + memcpy(&saved_hdr, ip6, sizeof(struct ip6_hdr)); + ip6 = (struct ip6_hdr *)&saved_hdr[0]; + } else { + memcpy(&saved_hdr, ip, ip->ip_hl << 2); + ip = (struct ip *)&saved_hdr[0]; + } + memcpy(&saved_tcphdr, th, sizeof(struct tcphdr)); if (sbappendstream_rcvdemux(so, m, th->th_seq - (tp->irs + 1), 0)) { - sorwakeup(so); + read_wakeup = 1; } + th = &saved_tcphdr; } else { - thflags = tcp_reass(tp, th, &tlen, m, ifp); + if (isipv6) { + memcpy(&saved_hdr, ip6, sizeof(struct ip6_hdr)); + ip6 = (struct ip6_hdr *)&saved_hdr[0]; + } else { + memcpy(&saved_hdr, ip, ip->ip_hl << 2); + ip = (struct ip *)&saved_hdr[0]; + } + memcpy(&saved_tcphdr, th, sizeof(struct tcphdr)); + thflags = tcp_reass(tp, th, &tlen, m, ifp, &read_wakeup); + th = &saved_tcphdr; tp->t_flags |= TF_ACKNOW; } - if (tlen > 0 && SACK_ENABLED(tp)) + if ((tlen > 0 || (th->th_flags & TH_FIN)) && SACK_ENABLED(tp)) { + if (th->th_flags & TH_FIN) { + save_end++; + } tcp_update_sack_list(tp, save_start, save_end); + } tcp_adaptive_rwtimo_check(tp, tlen); - if (tp->t_flags & TF_DELACK) - { + if (tlen > 0) { + tcp_tfo_rcv_data(tp); + } + + if (tp->t_flags & TF_DELACK) { #if INET6 if (isipv6) { KERNEL_DEBUG(DBG_LAYER_END, ((th->th_dport << 16) | th->th_sport), - (((ip6->ip6_src.s6_addr16[0]) << 16) | (ip6->ip6_dst.s6_addr16[0])), - th->th_seq, th->th_ack, th->th_win); - } - else + (((ip6->ip6_src.s6_addr16[0]) << 16) | (ip6->ip6_dst.s6_addr16[0])), + th->th_seq, th->th_ack, th->th_win); + } else #endif { KERNEL_DEBUG(DBG_LAYER_END, ((th->th_dport << 16) | th->th_sport), - (((ip->ip_src.s_addr & 0xffff) << 16) | (ip->ip_dst.s_addr & 0xffff)), - th->th_seq, th->th_ack, th->th_win); + (((ip->ip_src.s_addr & 0xffff) << 16) | (ip->ip_dst.s_addr & 0xffff)), + th->th_seq, th->th_ack, th->th_win); } - } } else { - m_freem(m); + if ((so->so_flags & SOF_MP_SUBFLOW) && tlen == 0 && + (m->m_pkthdr.pkt_flags & PKTF_MPTCP_DFIN) && + (m->m_pkthdr.pkt_flags & PKTF_MPTCP)) { + m_adj(m, drop_hdrlen); /* delayed header drop */ + mptcp_input(tptomptp(tp)->mpt_mpte, m); + tp->t_flags |= TF_ACKNOW; + } else { + m_freem(m); + } thflags &= ~TH_FIN; } @@ -4101,15 +5468,13 @@ dodata: tp->t_flags |= TF_DELACK; tp->t_timer[TCPT_DELACK] = OFFSET_FROM_START(tp, tcp_delack); } - } - else { + } else { tp->t_flags |= TF_ACKNOW; } tp->rcv_nxt++; } switch (tp->t_state) { - - /* + /* * In SYN_RECEIVED and ESTABLISHED STATES * enter the CLOSE_WAIT state. */ @@ -4117,39 +5482,38 @@ dodata: tp->t_starttime = tcp_now; case TCPS_ESTABLISHED: DTRACE_TCP4(state__change, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, int32_t, TCPS_CLOSE_WAIT); + struct tcpcb *, tp, int32_t, TCPS_CLOSE_WAIT); tp->t_state = TCPS_CLOSE_WAIT; break; - /* + /* * If still in FIN_WAIT_1 STATE FIN has not been acked so * enter the CLOSING state. */ case TCPS_FIN_WAIT_1: DTRACE_TCP4(state__change, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, int32_t, TCPS_CLOSING); + struct tcpcb *, tp, int32_t, TCPS_CLOSING); tp->t_state = TCPS_CLOSING; break; - /* + /* * In FIN_WAIT_2 state enter the TIME_WAIT state, * starting the time-wait timer, turning off the other * standard timers. */ case TCPS_FIN_WAIT_2: - DTRACE_TCP4(state__change, void, NULL, - struct inpcb *, inp, - struct tcpcb *, tp, - int32_t, TCPS_TIME_WAIT); + DTRACE_TCP4(state__change, void, NULL, + struct inpcb *, inp, + struct tcpcb *, tp, + int32_t, TCPS_TIME_WAIT); tp->t_state = TCPS_TIME_WAIT; tcp_canceltimers(tp); - if (tp->cc_recv != 0 && - ((int)(tcp_now - tp->t_starttime)) < tcp_msl) { - /* For transaction client, force ACK now. */ - tp->t_flags |= TF_ACKNOW; - tp->t_unacksegs = 0; + tp->t_flags |= TF_ACKNOW; + if (tp->t_flagsext & TF_NOTIMEWAIT) { + tp->t_flags |= TF_CLOSING; + } else { + add_to_time_wait(tp, 2 * tcp_msl); } - add_to_time_wait(tp, 2 * tcp_msl); soisdisconnected(so); break; @@ -4162,11 +5526,16 @@ dodata: } } #if TCPDEBUG - if (so->so_options & SO_DEBUG) + if (so->so_options & SO_DEBUG) { tcp_trace(TA_INPUT, ostate, tp, (void *)tcp_saveipgen, - &tcp_savetcp, 0); + &tcp_savetcp, 0); + } #endif + if (read_wakeup) { + mptcp_handle_input(so); + } + /* * Return any desired output. */ @@ -4176,9 +5545,10 @@ dodata: tcp_check_timer_state(tp); - - tcp_unlock(so, 1, 0); - KERNEL_DEBUG(DBG_FNC_TCP_INPUT | DBG_FUNC_END,0,0,0,0,0); + tcp_handle_wakeup(so, read_wakeup, write_wakeup); + + socket_unlock(so, 1); + KERNEL_DEBUG(DBG_FNC_TCP_INPUT | DBG_FUNC_END, 0, 0, 0, 0, 0); return; dropafterack: @@ -4199,23 +5569,27 @@ dropafterack: */ if (tp->t_state == TCPS_SYN_RECEIVED && (thflags & TH_ACK) && (SEQ_GT(tp->snd_una, th->th_ack) || - SEQ_GT(th->th_ack, tp->snd_max)) ) { + SEQ_GT(th->th_ack, tp->snd_max))) { rstreason = BANDLIM_RST_OPENPORT; IF_TCP_STATINC(ifp, dospacket); goto dropwithreset; } #if TCPDEBUG - if (so->so_options & SO_DEBUG) + if (so->so_options & SO_DEBUG) { tcp_trace(TA_DROP, ostate, tp, (void *)tcp_saveipgen, - &tcp_savetcp, 0); + &tcp_savetcp, 0); + } #endif m_freem(m); tp->t_flags |= TF_ACKNOW; + (void) tcp_output(tp); + tcp_handle_wakeup(so, read_wakeup, write_wakeup); + /* Don't need to check timer state as we should have done it during tcp_output */ - tcp_unlock(so, 1, 0); - KERNEL_DEBUG(DBG_FNC_TCP_INPUT | DBG_FUNC_END,0,0,0,0,0); + socket_unlock(so, 1); + KERNEL_DEBUG(DBG_FNC_TCP_INPUT | DBG_FUNC_END, 0, 0, 0, 0, 0); return; dropwithresetnosock: nosock = 1; @@ -4225,54 +5599,66 @@ dropwithreset: * Make ACK acceptable to originator of segment. * Don't bother to respond if destination was broadcast/multicast. */ - if ((thflags & TH_RST) || m->m_flags & (M_BCAST|M_MCAST)) + if ((thflags & TH_RST) || m->m_flags & (M_BCAST | M_MCAST)) { goto drop; + } #if INET6 if (isipv6) { if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst) || - IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) + IN6_IS_ADDR_MULTICAST(&ip6->ip6_src)) { goto drop; + } } else #endif /* INET6 */ if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr)) || IN_MULTICAST(ntohl(ip->ip_src.s_addr)) || ip->ip_src.s_addr == htonl(INADDR_BROADCAST) || - in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) + in_broadcast(ip->ip_dst, m->m_pkthdr.rcvif)) { goto drop; + } /* IPv6 anycast check is done at tcp6_input() */ - /* + /* * Perform bandwidth limiting. */ #if ICMP_BANDLIM - if (badport_bandlim(rstreason) < 0) + if (badport_bandlim(rstreason) < 0) { goto drop; + } #endif #if TCPDEBUG - if (tp == 0 || (tp->t_inpcb->inp_socket->so_options & SO_DEBUG)) + if (tp == 0 || (tp->t_inpcb->inp_socket->so_options & SO_DEBUG)) { tcp_trace(TA_DROP, ostate, tp, (void *)tcp_saveipgen, - &tcp_savetcp, 0); + &tcp_savetcp, 0); + } #endif - if (thflags & TH_ACK) + bzero(&tra, sizeof(tra)); + tra.ifscope = ifscope; + tra.awdl_unrestricted = 1; + tra.intcoproc_allowed = 1; + if (thflags & TH_ACK) { /* mtod() below is safe as long as hdr dropping is delayed */ tcp_respond(tp, mtod(m, void *), th, m, (tcp_seq)0, th->th_ack, - TH_RST, ifscope, nocell); - else { - if (thflags & TH_SYN) + TH_RST, &tra); + } else { + if (thflags & TH_SYN) { tlen++; + } /* mtod() below is safe as long as hdr dropping is delayed */ - tcp_respond(tp, mtod(m, void *), th, m, th->th_seq+tlen, - (tcp_seq)0, TH_RST|TH_ACK, ifscope, nocell); + tcp_respond(tp, mtod(m, void *), th, m, th->th_seq + tlen, + (tcp_seq)0, TH_RST | TH_ACK, &tra); } /* destroy temporarily created socket */ if (dropsocket) { - (void) soabort(so); - tcp_unlock(so, 1, 0); + (void) soabort(so); + socket_unlock(so, 1); } else if ((inp != NULL) && (nosock == 0)) { - tcp_unlock(so, 1, 0); + tcp_handle_wakeup(so, read_wakeup, write_wakeup); + + socket_unlock(so, 1); } - KERNEL_DEBUG(DBG_FNC_TCP_INPUT | DBG_FUNC_END,0,0,0,0,0); + KERNEL_DEBUG(DBG_FNC_TCP_INPUT | DBG_FUNC_END, 0, 0, 0, 0, 0); return; dropnosock: nosock = 1; @@ -4281,78 +5667,83 @@ drop: * Drop space held by incoming segment and return. */ #if TCPDEBUG - if (tp == 0 || (tp->t_inpcb->inp_socket->so_options & SO_DEBUG)) + if (tp == 0 || (tp->t_inpcb->inp_socket->so_options & SO_DEBUG)) { tcp_trace(TA_DROP, ostate, tp, (void *)tcp_saveipgen, - &tcp_savetcp, 0); + &tcp_savetcp, 0); + } #endif m_freem(m); /* destroy temporarily created socket */ if (dropsocket) { - (void) soabort(so); - tcp_unlock(so, 1, 0); - } - else if (nosock == 0) { - tcp_unlock(so, 1, 0); + (void) soabort(so); + socket_unlock(so, 1); + } else if (nosock == 0) { + tcp_handle_wakeup(so, read_wakeup, write_wakeup); + + socket_unlock(so, 1); } - KERNEL_DEBUG(DBG_FNC_TCP_INPUT | DBG_FUNC_END,0,0,0,0,0); + KERNEL_DEBUG(DBG_FNC_TCP_INPUT | DBG_FUNC_END, 0, 0, 0, 0, 0); return; } -static void -tcp_dooptions(tp, cp, cnt, th, to, input_ifscope) /* * Parse TCP options and place in tcpopt. */ - struct tcpcb *tp; - u_char *cp; - int cnt; - struct tcphdr *th; - struct tcpopt *to; - unsigned int input_ifscope; +static void +tcp_dooptions(struct tcpcb *tp, u_char *cp, int cnt, struct tcphdr *th, + struct tcpopt *to) { u_short mss = 0; int opt, optlen; for (; cnt > 0; cnt -= optlen, cp += optlen) { opt = cp[0]; - if (opt == TCPOPT_EOL) + if (opt == TCPOPT_EOL) { break; - if (opt == TCPOPT_NOP) + } + if (opt == TCPOPT_NOP) { optlen = 1; - else { - if (cnt < 2) + } else { + if (cnt < 2) { break; + } optlen = cp[1]; - if (optlen < 2 || optlen > cnt) + if (optlen < 2 || optlen > cnt) { break; + } } switch (opt) { - default: continue; case TCPOPT_MAXSEG: - if (optlen != TCPOLEN_MAXSEG) + if (optlen != TCPOLEN_MAXSEG) { continue; - if (!(th->th_flags & TH_SYN)) + } + if (!(th->th_flags & TH_SYN)) { continue; + } bcopy((char *) cp + 2, (char *) &mss, sizeof(mss)); NTOHS(mss); + to->to_mss = mss; + to->to_flags |= TOF_MSS; break; case TCPOPT_WINDOW: - if (optlen != TCPOLEN_WINDOW) + if (optlen != TCPOLEN_WINDOW) { continue; - if (!(th->th_flags & TH_SYN)) + } + if (!(th->th_flags & TH_SYN)) { continue; + } to->to_flags |= TOF_SCALE; - tp->t_flags |= TF_RCVD_SCALE; - tp->requested_s_scale = min(cp[2], TCP_MAX_WINSHIFT); + to->to_requested_s_scale = min(cp[2], TCP_MAX_WINSHIFT); break; case TCPOPT_TIMESTAMP: - if (optlen != TCPOLEN_TIMESTAMP) + if (optlen != TCPOLEN_TIMESTAMP) { continue; + } to->to_flags |= TOF_TS; bcopy((char *)cp + 2, (char *)&to->to_tsval, sizeof(to->to_tsval)); @@ -4360,32 +5751,53 @@ tcp_dooptions(tp, cp, cnt, th, to, input_ifscope) bcopy((char *)cp + 6, (char *)&to->to_tsecr, sizeof(to->to_tsecr)); NTOHL(to->to_tsecr); - /* - * A timestamp received in a SYN makes - * it ok to send timestamp requests and replies. - */ - if (th->th_flags & TH_SYN) { - tp->t_flags |= TF_RCVD_TSTMP; - tp->ts_recent = to->to_tsval; - tp->ts_recent_age = tcp_now; + /* Re-enable sending Timestamps if we received them */ + if (!(tp->t_flags & TF_REQ_TSTMP) && + tcp_do_rfc1323 == 1) { + tp->t_flags |= TF_REQ_TSTMP; } break; case TCPOPT_SACK_PERMITTED: if (!tcp_do_sack || - optlen != TCPOLEN_SACK_PERMITTED) + optlen != TCPOLEN_SACK_PERMITTED) { continue; - if (th->th_flags & TH_SYN) + } + if (th->th_flags & TH_SYN) { to->to_flags |= TOF_SACK; + } break; case TCPOPT_SACK: - if (optlen <= 2 || (optlen - 2) % TCPOLEN_SACK != 0) + if (optlen <= 2 || (optlen - 2) % TCPOLEN_SACK != 0) { continue; + } to->to_nsacks = (optlen - 2) / TCPOLEN_SACK; to->to_sacks = cp + 2; tcpstat.tcps_sack_rcv_blocks++; break; - + case TCPOPT_FASTOPEN: + if (optlen == TCPOLEN_FASTOPEN_REQ) { + if (tp->t_state != TCPS_LISTEN) { + continue; + } + + to->to_flags |= TOF_TFOREQ; + } else { + if (optlen < TCPOLEN_FASTOPEN_REQ || + (optlen - TCPOLEN_FASTOPEN_REQ) > TFO_COOKIE_LEN_MAX || + (optlen - TCPOLEN_FASTOPEN_REQ) < TFO_COOKIE_LEN_MIN) { + continue; + } + if (tp->t_state != TCPS_LISTEN && + tp->t_state != TCPS_SYN_SENT) { + continue; + } + + to->to_flags |= TOF_TFO; + to->to_tfo = cp + 1; + } + + break; #if MPTCP case TCPOPT_MULTIPATH: tcp_do_mptcp_options(tp, cp, th, to, optlen); @@ -4393,8 +5805,35 @@ tcp_dooptions(tp, cp, cnt, th, to, input_ifscope) #endif /* MPTCP */ } } - if (th->th_flags & TH_SYN) - tcp_mss(tp, mss, input_ifscope); /* sets t_maxseg */ +} + +static void +tcp_finalize_options(struct tcpcb *tp, struct tcpopt *to, unsigned int ifscope) +{ + if (to->to_flags & TOF_TS) { + tp->t_flags |= TF_RCVD_TSTMP; + tp->ts_recent = to->to_tsval; + tp->ts_recent_age = tcp_now; + } + if (to->to_flags & TOF_MSS) { + tcp_mss(tp, to->to_mss, ifscope); + } + if (SACK_ENABLED(tp)) { + if (!(to->to_flags & TOF_SACK)) { + tp->t_flagsext &= ~(TF_SACK_ENABLE); + } else { + tp->t_flags |= TF_SACK_PERMIT; + } + } + if (to->to_flags & TOF_SCALE) { + tp->t_flags |= TF_RCVD_SCALE; + tp->requested_s_scale = to->to_requested_s_scale; + + /* Re-enable window scaling, if the option is received */ + if (tp->request_r_scale > 0) { + tp->t_flags |= TF_REQ_SCALE; + } + } } /* @@ -4402,13 +5841,11 @@ tcp_dooptions(tp, cp, cnt, th, to, input_ifscope) * it doesn't appear in the user's data queue. * It is still reflected in the segment length for * sequencing purposes. + * + * @param off delayed to be droped hdrlen */ static void -tcp_pulloutofband(so, th, m, off) - struct socket *so; - struct tcphdr *th; - register struct mbuf *m; - int off; /* delayed to be droped hdrlen */ +tcp_pulloutofband(struct socket *so, struct tcphdr *th, struct mbuf *m, int off) { int cnt = off + th->th_urp - 1; @@ -4419,30 +5856,27 @@ tcp_pulloutofband(so, th, m, off) tp->t_iobc = *cp; tp->t_oobflags |= TCPOOB_HAVEDATA; - bcopy(cp+1, cp, (unsigned)(m->m_len - cnt - 1)); + bcopy(cp + 1, cp, (unsigned)(m->m_len - cnt - 1)); m->m_len--; - if (m->m_flags & M_PKTHDR) + if (m->m_flags & M_PKTHDR) { m->m_pkthdr.len--; + } return; } cnt -= m->m_len; m = m->m_next; - if (m == 0) + if (m == 0) { break; + } } panic("tcp_pulloutofband"); } uint32_t -get_base_rtt(struct tcpcb *tp) +get_base_rtt(struct tcpcb *tp) { - uint32_t base_rtt = 0, i; - for (i = 0; i < N_RTT_BASE; ++i) { - if (tp->rtt_hist[i] != 0 && - (base_rtt == 0 || tp->rtt_hist[i] < base_rtt)) - base_rtt = tp->rtt_hist[i]; - } - return base_rtt; + struct rtentry *rt = tp->t_inpcb->inp_route.ro_rt; + return (rt == NULL) ? 0 : rt->rtt_min; } /* Each value of RTT base represents the minimum RTT seen in a minute. @@ -4451,70 +5885,152 @@ get_base_rtt(struct tcpcb *tp) void update_base_rtt(struct tcpcb *tp, uint32_t rtt) { - int32_t i, qdelay; - u_int32_t base_rtt; + u_int32_t base_rtt, i; + struct rtentry *rt; - if (++tp->rtt_count >= rtt_samples_per_slot) { + if ((rt = tp->t_inpcb->inp_route.ro_rt) == NULL) { + return; + } + if (rt->rtt_expire_ts == 0) { + RT_LOCK_SPIN(rt); + if (rt->rtt_expire_ts != 0) { + RT_UNLOCK(rt); + goto update; + } + rt->rtt_expire_ts = tcp_now; + rt->rtt_index = 0; + rt->rtt_hist[0] = rtt; + rt->rtt_min = rtt; + RT_UNLOCK(rt); + return; + } +update: #if TRAFFIC_MGT - /* - * If the recv side is being throttled, check if the - * current RTT is closer to the base RTT seen in - * first (recent) two slots. If so, unthrottle the stream. - */ - if (tp->t_flagsext & TF_RECV_THROTTLE) { - base_rtt = min(tp->rtt_hist[0], tp->rtt_hist[1]); - qdelay = tp->t_rttcur - base_rtt; - if (qdelay < target_qdelay) - tp->t_flagsext &= ~(TF_RECV_THROTTLE); + /* + * If the recv side is being throttled, check if the + * current RTT is closer to the base RTT seen in + * first (recent) two slots. If so, unthrottle the stream. + */ + if ((tp->t_flagsext & TF_RECV_THROTTLE) && + (int)(tcp_now - tp->t_recv_throttle_ts) >= TCP_RECV_THROTTLE_WIN) { + base_rtt = rt->rtt_min; + if (tp->t_rttcur <= (base_rtt + target_qdelay)) { + tp->t_flagsext &= ~TF_RECV_THROTTLE; + tp->t_recv_throttle_ts = 0; } + } #endif /* TRAFFIC_MGT */ - - for (i = (N_RTT_BASE-1); i > 0; --i) { - tp->rtt_hist[i] = tp->rtt_hist[i-1]; + if ((int)(tcp_now - rt->rtt_expire_ts) >= + TCP_RTT_HISTORY_EXPIRE_TIME) { + RT_LOCK_SPIN(rt); + /* check the condition again to avoid race */ + if ((int)(tcp_now - rt->rtt_expire_ts) >= + TCP_RTT_HISTORY_EXPIRE_TIME) { + rt->rtt_index++; + if (rt->rtt_index >= NRTT_HIST) { + rt->rtt_index = 0; + } + rt->rtt_hist[rt->rtt_index] = rtt; + rt->rtt_expire_ts = tcp_now; + } else { + rt->rtt_hist[rt->rtt_index] = + min(rt->rtt_hist[rt->rtt_index], rtt); + } + /* forget the old value and update minimum */ + rt->rtt_min = 0; + for (i = 0; i < NRTT_HIST; ++i) { + if (rt->rtt_hist[i] != 0 && + (rt->rtt_min == 0 || + rt->rtt_hist[i] < rt->rtt_min)) { + rt->rtt_min = rt->rtt_hist[i]; + } } - tp->rtt_hist[0] = rtt; - tp->rtt_count = 0; + RT_UNLOCK(rt); } else { - tp->rtt_hist[0] = min(tp->rtt_hist[0], rtt); + rt->rtt_hist[rt->rtt_index] = + min(rt->rtt_hist[rt->rtt_index], rtt); + if (rt->rtt_min == 0) { + rt->rtt_min = rtt; + } else { + rt->rtt_min = min(rt->rtt_min, rtt); + } } } /* * If we have a timestamp reply, update smoothed RTT. If no timestamp is - * present but transmit timer is running and timed sequence number was - * acked, update smoothed RTT. + * present but transmit timer is running and timed sequence number was + * acked, update smoothed RTT. * * If timestamps are supported, a receiver can update RTT even if * there is no outstanding data. * * Some boxes send broken timestamp replies during the SYN+ACK phase, - * ignore timestamps of 0or we could calculate a huge RTT and blow up + * ignore timestamps of 0or we could calculate a huge RTT and blow up * the retransmit timer. */ static void tcp_compute_rtt(struct tcpcb *tp, struct tcpopt *to, struct tcphdr *th) { + int rtt = 0; VERIFY(to != NULL && th != NULL); - if (((to->to_flags & TOF_TS) != 0) && - (to->to_tsecr != 0) && - TSTMP_GEQ(tcp_now, to->to_tsecr)) { - tcp_xmit_timer(tp, tcp_now - to->to_tsecr, - to->to_tsecr, th->th_ack); - } else if (tp->t_rtttime && SEQ_GT(th->th_ack, tp->t_rtseq)) { - tcp_xmit_timer(tp, tcp_now - tp->t_rtttime, 0, - th->th_ack); + if (tp->t_rtttime != 0 && SEQ_GT(th->th_ack, tp->t_rtseq)) { + u_int32_t pipe_ack_val; + rtt = tcp_now - tp->t_rtttime; + /* + * Compute pipe ack -- the amount of data acknowledged + * in the last RTT + */ + if (SEQ_GT(th->th_ack, tp->t_pipeack_lastuna)) { + pipe_ack_val = th->th_ack - tp->t_pipeack_lastuna; + /* Update the sample */ + tp->t_pipeack_sample[tp->t_pipeack_ind++] = + pipe_ack_val; + tp->t_pipeack_ind %= TCP_PIPEACK_SAMPLE_COUNT; + + /* Compute the max of the pipeack samples */ + pipe_ack_val = tcp_get_max_pipeack(tp); + tp->t_pipeack = (pipe_ack_val > + TCP_CC_CWND_INIT_BYTES) ? + pipe_ack_val : 0; + } + /* start another measurement */ + tp->t_rtttime = 0; + } + if (((to->to_flags & TOF_TS) != 0) && + (to->to_tsecr != 0) && + TSTMP_GEQ(tcp_now, to->to_tsecr)) { + tcp_xmit_timer(tp, (tcp_now - to->to_tsecr), + to->to_tsecr, th->th_ack); + } else if (rtt > 0) { + tcp_xmit_timer(tp, rtt, 0, th->th_ack); } } /* - * Collect new round-trip time estimate - * and update averages and current timeout. + * Collect new round-trip time estimate and update averages and + * current timeout. */ static void -tcp_xmit_timer(register struct tcpcb *tp, int rtt, - u_int32_t tsecr, tcp_seq th_ack) +tcp_xmit_timer(struct tcpcb *tp, int rtt, + u_int32_t tsecr, tcp_seq th_ack) { - register int delta; + int delta; + int old_srtt = tp->t_srtt; + int old_rttvar = tp->t_rttvar; + bool log_rtt = false; + + /* + * On AWDL interface, the initial RTT measurement on SYN + * can be wrong due to peer caching. Avoid the first RTT + * measurement as it might skew up the RTO. + * + */ + if (tp->t_inpcb->inp_last_outifp != NULL && + (tp->t_inpcb->inp_last_outifp->if_eflags & IFEF_AWDL) && + th_ack == tp->iss + 1) { + return; + } if (tp->t_flagsext & TF_RECOMPUTE_RTT) { if (SEQ_GT(th_ack, tp->snd_una) && @@ -4523,7 +6039,7 @@ tcp_xmit_timer(register struct tcpcb *tp, int rtt, TSTMP_GEQ(tsecr, tp->t_badrexmt_time))) { /* * We received a new ACk after a - * spurious timeout. Adapt retransmission + * spurious timeout. Adapt retransmission * timer as described in rfc 4015. */ tp->t_flagsext &= ~(TF_RECOMPUTE_RTT); @@ -4533,8 +6049,9 @@ tcp_xmit_timer(register struct tcpcb *tp, int rtt, tp->t_rttvar = max(tp->t_rttvar_prev, (rtt >> 1)); tp->t_rttvar = tp->t_rttvar << TCP_RTTVAR_SHIFT; - if (tp->t_rttbest > (tp->t_srtt + tp->t_rttvar)) + if (tp->t_rttbest > (tp->t_srtt + tp->t_rttvar)) { tp->t_rttbest = tp->t_srtt + tp->t_rttvar; + } goto compute_rto; } else { @@ -4558,17 +6075,18 @@ tcp_xmit_timer(register struct tcpcb *tp, int rtt, * an alpha of .875 (srtt = rtt/8 + srtt*7/8 in fixed * point). * - * Freebsd adjusts rtt to origin 0 by subtracting 1 - * from the provided rtt value. This was required because - * of the way t_rtttime was initiailised to 1 before. + * Freebsd adjusts rtt to origin 0 by subtracting 1 + * from the provided rtt value. This was required because + * of the way t_rtttime was initiailised to 1 before. * Since we changed t_rtttime to be based on * tcp_now, this extra adjustment is not needed. */ delta = (rtt << TCP_DELTA_SHIFT) - - (tp->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT)); + - (tp->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT)); - if ((tp->t_srtt += delta) <= 0) + if ((tp->t_srtt += delta) <= 0) { tp->t_srtt = 1; + } /* * We accumulate a smoothed rtt variance (actually, a @@ -4580,14 +6098,17 @@ tcp_xmit_timer(register struct tcpcb *tp, int rtt, * (rttvar = rttvar*3/4 + |delta| / 4). This replaces * rfc793's wired-in beta. */ - if (delta < 0) + if (delta < 0) { delta = -delta; + } delta -= tp->t_rttvar >> (TCP_RTTVAR_SHIFT - TCP_DELTA_SHIFT); - if ((tp->t_rttvar += delta) <= 0) + if ((tp->t_rttvar += delta) <= 0) { tp->t_rttvar = 1; - if (tp->t_rttbest == 0 || - tp->t_rttbest > (tp->t_srtt + tp->t_rttvar)) + } + if (tp->t_rttbest == 0 || + tp->t_rttbest > (tp->t_srtt + tp->t_rttvar)) { tp->t_rttbest = tp->t_srtt + tp->t_rttvar; + } } else { /* * No rtt measurement yet - use the unsmoothed rtt. @@ -4599,11 +6120,8 @@ tcp_xmit_timer(register struct tcpcb *tp, int rtt, } compute_rto: - nstat_route_rtt(tp->t_inpcb->inp_route.ro_rt, tp->t_srtt, - tp->t_rttvar); - tp->t_rtttime = 0; - tp->t_rxtshift = 0; - tp->t_rxtstart = 0; + nstat_route_rtt(tp->t_inpcb->inp_route.ro_rt, tp->t_srtt, + tp->t_rttvar); /* * the retransmit should happen at rtt + 4 * rttvar. @@ -4617,8 +6135,8 @@ compute_rto: * the minimum feasible timer (which is 2 ticks). */ TCPT_RANGESET(tp->t_rxtcur, TCP_REXMTVAL(tp), - max(tp->t_rttmin, rtt + 2), TCPTV_REXMTMAX, - TCP_ADD_REXMTSLOP(tp)); + max(tp->t_rttmin, rtt + 2), TCPTV_REXMTMAX, + TCP_ADD_REXMTSLOP(tp)); /* * We received an ack for a packet that wasn't retransmitted; @@ -4628,20 +6146,37 @@ compute_rto: * and the return path might not be symmetrical). */ tp->t_softerror = 0; + + if (log_rtt) { + TCP_LOG_RTT_INFO(tp); + } + + TCP_LOG_RTT_CHANGE(tp, old_srtt, old_rttvar); } static inline unsigned int tcp_maxmtu(struct rtentry *rt) { unsigned int maxmtu; + int interface_mtu = 0; RT_LOCK_ASSERT_HELD(rt); - if (rt->rt_rmx.rmx_mtu == 0) - maxmtu = rt->rt_ifp->if_mtu; - else - maxmtu = MIN(rt->rt_rmx.rmx_mtu, rt->rt_ifp->if_mtu); + interface_mtu = rt->rt_ifp->if_mtu; + + if (rt_key(rt)->sa_family == AF_INET && + INTF_ADJUST_MTU_FOR_CLAT46(rt->rt_ifp)) { + interface_mtu = IN6_LINKMTU(rt->rt_ifp); + /* Further adjust the size for CLAT46 expansion */ + interface_mtu -= CLAT46_HDR_EXPANSION_OVERHD; + } + + if (rt->rt_rmx.rmx_mtu == 0) { + maxmtu = interface_mtu; + } else { + maxmtu = MIN(rt->rt_rmx.rmx_mtu, interface_mtu); + } - return (maxmtu); + return maxmtu; } #if INET6 @@ -4649,26 +6184,48 @@ static inline unsigned int tcp_maxmtu6(struct rtentry *rt) { unsigned int maxmtu; - struct nd_ifinfo *ndi; + struct nd_ifinfo *ndi = NULL; RT_LOCK_ASSERT_HELD(rt); - lck_rw_lock_shared(nd_if_rwlock); - if ((ndi = ND_IFINFO(rt->rt_ifp)) != NULL && !ndi->initialized) + if ((ndi = ND_IFINFO(rt->rt_ifp)) != NULL && !ndi->initialized) { ndi = NULL; - if (ndi != NULL) + } + if (ndi != NULL) { lck_mtx_lock(&ndi->lock); - if (rt->rt_rmx.rmx_mtu == 0) + } + if (rt->rt_rmx.rmx_mtu == 0) { maxmtu = IN6_LINKMTU(rt->rt_ifp); - else + } else { maxmtu = MIN(rt->rt_rmx.rmx_mtu, IN6_LINKMTU(rt->rt_ifp)); - if (ndi != NULL) + } + if (ndi != NULL) { lck_mtx_unlock(&ndi->lock); - lck_rw_done(nd_if_rwlock); + } - return (maxmtu); + return maxmtu; } #endif +unsigned int +get_maxmtu(struct rtentry *rt) +{ + unsigned int maxmtu = 0; + + RT_LOCK_ASSERT_NOTHELD(rt); + + RT_LOCK(rt); + + if (rt_key(rt)->sa_family == AF_INET6) { + maxmtu = tcp_maxmtu6(rt); + } else { + maxmtu = tcp_maxmtu(rt); + } + + RT_UNLOCK(rt); + + return maxmtu; +} + /* * Determine a reasonable value for maxseg size. * If the route is known, check route for mtu. @@ -4680,9 +6237,9 @@ tcp_maxmtu6(struct rtentry *rt) * size (usually 512 or the default IP max size, but no more than the mtu * of the interface), as we can't discover anything about intervening * gateways or networks. We also initialize the congestion/slow start - * window to be a single segment if the destination isn't local. - * While looking at the routing entry, we also initialize other path-dependent - * parameters from pre-set or cached values in the routing entry. + * window. While looking at the routing entry, we also initialize + * other path-dependent parameters from pre-set or cached values + * in the routing entry. * * Also take into account the space needed for options that we * send regularly. Make maxseg shorter by that amount to assure @@ -4695,14 +6252,11 @@ tcp_maxmtu6(struct rtentry *rt) * */ void -tcp_mss(tp, offer, input_ifscope) - struct tcpcb *tp; - int offer; - unsigned int input_ifscope; +tcp_mss(struct tcpcb *tp, int offer, unsigned int input_ifscope) { - register struct rtentry *rt; + struct rtentry *rt; struct ifnet *ifp; - register int rtt, mss; + int rtt, mss; u_int32_t bufsize; struct inpcb *inp; struct socket *so; @@ -4716,10 +6270,19 @@ tcp_mss(tp, offer, input_ifscope) #endif inp = tp->t_inpcb; + + so = inp->inp_socket; + /* + * Nothing left to send after the socket is defunct or TCP is in the closed state + */ + if ((so->so_state & SS_DEFUNCT) || tp->t_state == TCPS_CLOSED) { + return; + } + #if INET6 isipv6 = ((inp->inp_vflag & INP_IPV6) != 0) ? 1 : 0; - min_protoh = isipv6 ? sizeof (struct ip6_hdr) + sizeof (struct tcphdr) - : sizeof (struct tcpiphdr); + min_protoh = isipv6 ? sizeof(struct ip6_hdr) + sizeof(struct tcphdr) + : sizeof(struct tcpiphdr); #else #define min_protoh (sizeof (struct tcpiphdr)) #endif @@ -4727,8 +6290,7 @@ tcp_mss(tp, offer, input_ifscope) #if INET6 if (isipv6) { rt = tcp_rtlookup6(inp, input_ifscope); - } - else + } else #endif /* INET6 */ { rt = tcp_rtlookup(inp, input_ifscope); @@ -4738,42 +6300,43 @@ tcp_mss(tp, offer, input_ifscope) if (rt == NULL) { tp->t_maxopd = tp->t_maxseg = #if INET6 - isipv6 ? tcp_v6mssdflt : + isipv6 ? tcp_v6mssdflt : #endif /* INET6 */ - tcp_mssdflt; + tcp_mssdflt; return; } ifp = rt->rt_ifp; /* * Slower link window correction: - * If a value is specificied for slowlink_wsize use it for PPP links - * believed to be on a serial modem (speed <128Kbps). Excludes 9600bps as - * it is the default value adversized by pseudo-devices over ppp. + * If a value is specificied for slowlink_wsize use it for + * PPP links believed to be on a serial modem (speed <128Kbps). + * Excludes 9600bps as it is the default value adversized + * by pseudo-devices over ppp. */ - if (ifp->if_type == IFT_PPP && slowlink_wsize > 0 && + if (ifp->if_type == IFT_PPP && slowlink_wsize > 0 && ifp->if_baudrate > 9600 && ifp->if_baudrate <= 128000) { tp->t_flags |= TF_SLOWLINK; } - so = inp->inp_socket; taop = rmx_taop(rt->rt_rmx); /* * Offer == -1 means that we didn't receive SYN yet, * use cached value in that case; */ - if (offer == -1) + if (offer == -1) { offer = taop->tao_mssopt; + } /* * Offer == 0 means that there was no MSS on the SYN segment, * in this case we use tcp_mssdflt. */ - if (offer == 0) + if (offer == 0) { offer = #if INET6 - isipv6 ? tcp_v6mssdflt : + isipv6 ? tcp_v6mssdflt : #endif /* INET6 */ - tcp_mssdflt; - else { + tcp_mssdflt; + } else { /* * Prevent DoS attack with too small MSS. Round up * to at least minmss. @@ -4805,17 +6368,25 @@ tcp_mss(tp, offer, input_ifscope) #else mss = tcp_maxmtu(rt); #endif + +#if NECP + // At this point, the mss is just the MTU. Adjust if necessary. + mss = necp_socket_get_effective_mtu(inp, mss); +#endif /* NECP */ + mss -= min_protoh; if (rt->rt_rmx.rmx_mtu == 0) { #if INET6 if (isipv6) { - if (!isnetlocal) + if (!isnetlocal) { mss = min(mss, tcp_v6mssdflt); + } } else #endif /* INET6 */ - if (!isnetlocal) + if (!isnetlocal) { mss = min(mss, tcp_mssdflt); + } } mss = min(mss, offer); @@ -4832,16 +6403,17 @@ tcp_mss(tp, offer, input_ifscope) * origoffer==-1 indicates, that no segments were received yet. * In this case we just guess. */ - if ((tp->t_flags & (TF_REQ_TSTMP|TF_NOOPT)) == TF_REQ_TSTMP && + if ((tp->t_flags & (TF_REQ_TSTMP | TF_NOOPT)) == TF_REQ_TSTMP && (origoffer == -1 || - (tp->t_flags & TF_RCVD_TSTMP) == TF_RCVD_TSTMP)) + (tp->t_flags & TF_RCVD_TSTMP) == TF_RCVD_TSTMP)) { mss -= TCPOLEN_TSTAMP_APPA; + } #if MPTCP mss -= mptcp_adj_mss(tp, FALSE); #endif /* MPTCP */ tp->t_maxseg = mss; - + /* * Calculate corrected value for sb_max; ensure to upgrade the * numerator for large sb_max values else it will overflow. @@ -4859,26 +6431,36 @@ tcp_mss(tp, offer, input_ifscope) bufsize = rt->rt_rmx.rmx_sendpipe; if (bufsize < so->so_snd.sb_hiwat) #endif - bufsize = so->so_snd.sb_hiwat; - if (bufsize < mss) + bufsize = so->so_snd.sb_hiwat; + if (bufsize < mss) { mss = bufsize; - else { + } else { bufsize = (((bufsize + (u_int64_t)mss - 1) / (u_int64_t)mss) * (u_int64_t)mss); - if (bufsize > sb_max_corrected) + if (bufsize > sb_max_corrected) { bufsize = sb_max_corrected; + } (void)sbreserve(&so->so_snd, bufsize); } tp->t_maxseg = mss; + ASSERT(tp->t_maxseg); + + /* + * Update MSS using recommendation from link status report. This is + * temporary + */ + tcp_update_mss_locked(so, ifp); + #if RTV_RPIPE bufsize = rt->rt_rmx.rmx_recvpipe; if (bufsize < so->so_rcv.sb_hiwat) #endif - bufsize = so->so_rcv.sb_hiwat; + bufsize = so->so_rcv.sb_hiwat; if (bufsize > mss) { bufsize = (((bufsize + (u_int64_t)mss - 1) / (u_int64_t)mss) * (u_int64_t)mss); - if (bufsize > sb_max_corrected) + if (bufsize > sb_max_corrected) { bufsize = sb_max_corrected; + } (void)sbreserve(&so->so_rcv, bufsize); } @@ -4888,8 +6470,8 @@ tcp_mss(tp, offer, input_ifscope) /* * There's some sort of gateway or interface * buffer limit on the path. Use this to set - * the slow start threshhold, but set the - * threshold to no less than 2*mss. + * slow-start threshold, but set the threshold to + * no less than 2*mss. */ tp->snd_ssthresh = max(2 * mss, rt->rt_rmx.rmx_ssthresh); tcpstat.tcps_usedssthresh++; @@ -4897,16 +6479,15 @@ tcp_mss(tp, offer, input_ifscope) tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; } - /* * Set the slow-start flight size depending on whether this * is a local network or not. */ - if (CC_ALGO(tp)->cwnd_init != NULL) + if (CC_ALGO(tp)->cwnd_init != NULL) { CC_ALGO(tp)->cwnd_init(tp); + } - DTRACE_TCP5(cc, void, NULL, struct inpcb *, tp->t_inpcb, struct tcpcb *, tp, - struct tcphdr *, NULL, int32_t, TCP_CC_CWND_INIT); + tcp_ccdbg_trace(tp, NULL, TCP_CC_CWND_INIT); /* Route locked during lookup above */ RT_UNLOCK(rt); @@ -4916,8 +6497,7 @@ tcp_mss(tp, offer, input_ifscope) * Determine the MSS option to send on an outgoing SYN. */ int -tcp_mssopt(tp) - struct tcpcb *tp; +tcp_mssopt(struct tcpcb *tp) { struct rtentry *rt; int mss; @@ -4928,24 +6508,24 @@ tcp_mssopt(tp) #if INET6 isipv6 = ((tp->t_inpcb->inp_vflag & INP_IPV6) != 0) ? 1 : 0; - min_protoh = isipv6 ? sizeof (struct ip6_hdr) + sizeof (struct tcphdr) - : sizeof (struct tcpiphdr); + min_protoh = isipv6 ? sizeof(struct ip6_hdr) + sizeof(struct tcphdr) + : sizeof(struct tcpiphdr); #else #define min_protoh (sizeof (struct tcpiphdr)) #endif #if INET6 - if (isipv6) + if (isipv6) { rt = tcp_rtlookup6(tp->t_inpcb, IFSCOPE_NONE); - else + } else #endif /* INET6 */ rt = tcp_rtlookup(tp->t_inpcb, IFSCOPE_NONE); if (rt == NULL) { - return ( + return #if INET6 - isipv6 ? tcp_v6mssdflt : + isipv6 ? tcp_v6mssdflt : #endif /* INET6 */ - tcp_mssdflt); + tcp_mssdflt; } /* * Slower link window correction: @@ -4953,7 +6533,7 @@ tcp_mssopt(tp) * believed to be on a serial modem (speed <128Kbps). Excludes 9600bps as * it is the default value adversized by pseudo-devices over ppp. */ - if (rt->rt_ifp->if_type == IFT_PPP && slowlink_wsize > 0 && + if (rt->rt_ifp->if_type == IFT_PPP && slowlink_wsize > 0 && rt->rt_ifp->if_baudrate > 9600 && rt->rt_ifp->if_baudrate <= 128000) { tp->t_flags |= TF_SLOWLINK; } @@ -4965,7 +6545,13 @@ tcp_mssopt(tp) #endif /* Route locked during lookup above */ RT_UNLOCK(rt); - return (mss - min_protoh); + +#if NECP + // At this point, the mss is just the MTU. Adjust if necessary. + mss = necp_socket_get_effective_mtu(tp->t_inpcb, mss); +#endif /* NECP */ + + return mss - min_protoh; } /* @@ -4975,36 +6561,36 @@ tcp_mssopt(tp) * be started again. */ static void -tcp_newreno_partial_ack(tp, th) - struct tcpcb *tp; - struct tcphdr *th; +tcp_newreno_partial_ack(struct tcpcb *tp, struct tcphdr *th) { - tcp_seq onxt = tp->snd_nxt; - u_int32_t ocwnd = tp->snd_cwnd; - tp->t_timer[TCPT_REXMT] = 0; - tp->t_rtttime = 0; - tp->snd_nxt = th->th_ack; - /* - * Set snd_cwnd to one segment beyond acknowledged offset - * (tp->snd_una has not yet been updated when this function - * is called) - */ - tp->snd_cwnd = tp->t_maxseg + BYTES_ACKED(th, tp); - tp->t_flags |= TF_ACKNOW; - (void) tcp_output(tp); - tp->snd_cwnd = ocwnd; - if (SEQ_GT(onxt, tp->snd_nxt)) - tp->snd_nxt = onxt; - /* - * Partial window deflation. Relies on fact that tp->snd_una - * not updated yet. - */ - if (tp->snd_cwnd > BYTES_ACKED(th, tp)) - tp->snd_cwnd -= BYTES_ACKED(th, tp); - else - tp->snd_cwnd = 0; - tp->snd_cwnd += tp->t_maxseg; - + tcp_seq onxt = tp->snd_nxt; + u_int32_t ocwnd = tp->snd_cwnd; + tp->t_timer[TCPT_REXMT] = 0; + tp->t_timer[TCPT_PTO] = 0; + tp->t_rtttime = 0; + tp->snd_nxt = th->th_ack; + /* + * Set snd_cwnd to one segment beyond acknowledged offset + * (tp->snd_una has not yet been updated when this function + * is called) + */ + tp->snd_cwnd = tp->t_maxseg + BYTES_ACKED(th, tp); + tp->t_flags |= TF_ACKNOW; + (void) tcp_output(tp); + tp->snd_cwnd = ocwnd; + if (SEQ_GT(onxt, tp->snd_nxt)) { + tp->snd_nxt = onxt; + } + /* + * Partial window deflation. Relies on fact that tp->snd_una + * not updated yet. + */ + if (tp->snd_cwnd > BYTES_ACKED(th, tp)) { + tp->snd_cwnd -= BYTES_ACKED(th, tp); + } else { + tp->snd_cwnd = 0; + } + tp->snd_cwnd += tp->t_maxseg; } /* @@ -5028,13 +6614,18 @@ tcp_dropdropablreq(struct socket *head) struct inpcb *inp = NULL; struct tcpcb *tp; - if ((head->so_options & SO_ACCEPTCONN) == 0) - return (0); + if ((head->so_options & SO_ACCEPTCONN) == 0) { + return 0; + } + + if (TAILQ_EMPTY(&head->so_incomp)) { + return 0; + } - if (TAILQ_EMPTY(&head->so_incomp)) - return (0); + so_acquire_accept_list(head, NULL); + socket_unlock(head, 0); - /* + /* * Check if there is any socket in the incomp queue * that is closed because of a reset from the peer and is * waiting to be garbage collected. If so, pick that as @@ -5045,15 +6636,15 @@ tcp_dropdropablreq(struct socket *head) tp = intotcpcb(inp); if (tp != NULL && tp->t_state == TCPS_CLOSED && so->so_head != NULL && - (so->so_state & (SS_INCOMP|SS_CANTSENDMORE|SS_CANTRCVMORE)) == - (SS_INCOMP|SS_CANTSENDMORE|SS_CANTRCVMORE)) { - /* - * The listen socket is already locked but we + (so->so_state & (SS_INCOMP | SS_CANTSENDMORE | SS_CANTRCVMORE)) == + (SS_INCOMP | SS_CANTSENDMORE | SS_CANTRCVMORE)) { + /* + * The listen socket is already locked but we * can lock this socket here without lock ordering * issues because it is in the incomp queue and * is not visible to others. */ - if (lck_mtx_try_lock(&inp->inpcb_mtx)) { + if (socket_try_lock(so)) { so->so_usecount++; goto found_victim; } else { @@ -5070,52 +6661,52 @@ tcp_dropdropablreq(struct socket *head) old_cnt = cur_cnt / i; cur_cnt = 0; } - - + qlen = head->so_incqlen; - if (rnd == 0) + if (rnd == 0) { rnd = RandomULong(); + } if (++cur_cnt > qlen || old_cnt > qlen) { rnd = (314159 * rnd + 66329) & 0xffff; j = ((qlen + 1) * rnd) >> 16; - while (j-- && so) + while (j-- && so) { so = TAILQ_NEXT(so, so_list); + } } /* Find a connection that is not already closing (or being served) */ while (so) { inp = (struct inpcb *)so->so_pcb; - + sonext = TAILQ_NEXT(so, so_list); - if (in_pcb_checkstate(inp, WNT_ACQUIRE, 0) - != WNT_STOPUSING) { - /* + if (in_pcb_checkstate(inp, WNT_ACQUIRE, 0) != WNT_STOPUSING) { + /* * Avoid the issue of a socket being accepted - * by one input thread and being dropped by - * another input thread. If we can't get a hold - * on this mutex, then grab the next socket in + * by one input thread and being dropped by + * another input thread. If we can't get a hold + * on this mutex, then grab the next socket in * line. */ - if (lck_mtx_try_lock(&inp->inpcb_mtx)) { + if (socket_try_lock(so)) { so->so_usecount++; - if ((so->so_usecount == 2) && + if ((so->so_usecount == 2) && (so->so_state & SS_INCOMP) && - !(so->so_flags & SOF_INCOMP_INPROGRESS)) { + !(so->so_flags & SOF_INCOMP_INPROGRESS)) { break; } else { - /* - * don't use if being accepted or + /* + * don't use if being accepted or * used in any other way */ in_pcb_checkstate(inp, WNT_RELEASE, 1); - tcp_unlock(so, 1, 0); + socket_unlock(so, 1); } } else { - /* - * do not try to lock the inp in - * in_pcb_checkstate because the lock + /* + * do not try to lock the inp in + * in_pcb_checkstate because the lock * is already held in some other thread. * Only drop the inp_wntcnt reference. */ @@ -5123,72 +6714,84 @@ tcp_dropdropablreq(struct socket *head) } } so = sonext; - } if (so == NULL) { - return (0); + socket_lock(head, 0); + so_release_accept_list(head); + return 0; } /* Makes sure socket is still in the right state to be discarded */ if (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING) { - tcp_unlock(so, 1, 0); - return (0); + socket_unlock(so, 1); + socket_lock(head, 0); + so_release_accept_list(head); + return 0; } found_victim: if (so->so_usecount != 2 || !(so->so_state & SS_INCOMP)) { /* do not discard: that socket is being accepted */ - tcp_unlock(so, 1, 0); - return (0); + socket_unlock(so, 1); + socket_lock(head, 0); + so_release_accept_list(head); + return 0; } + socket_lock(head, 0); TAILQ_REMOVE(&head->so_incomp, so, so_list); - tcp_unlock(head, 0, 0); - - lck_mtx_assert(&inp->inpcb_mtx, LCK_MTX_ASSERT_OWNED); - tp = sototcpcb(so); + head->so_incqlen--; + head->so_qlen--; + so->so_state &= ~SS_INCOMP; so->so_flags |= SOF_OVERFLOW; so->so_head = NULL; + so_release_accept_list(head); + socket_unlock(head, 0); + + socket_lock_assert_owned(so); + tp = sototcpcb(so); tcp_close(tp); if (inp->inp_wantcnt > 0 && inp->inp_wantcnt != WNT_STOPUSING) { - /* + /* * Some one has a wantcnt on this pcb. Since WNT_ACQUIRE * doesn't require a lock, it could have happened while * we are holding the lock. This pcb will have to * be garbage collected later. * Release the reference held for so_incomp queue */ + VERIFY(so->so_usecount > 0); so->so_usecount--; - tcp_unlock(so, 1, 0); + socket_unlock(so, 1); } else { - /* - * Unlock this socket and leave the reference on. - * We need to acquire the pcbinfo lock in order to - * fully dispose it off + /* + * Unlock this socket and leave the reference on. + * We need to acquire the pcbinfo lock in order to + * fully dispose it off */ - tcp_unlock(so, 0, 0); + socket_unlock(so, 0); lck_rw_lock_exclusive(tcbinfo.ipi_lock); - tcp_lock(so, 0, 0); + socket_lock(so, 0); /* Release the reference held for so_incomp queue */ + VERIFY(so->so_usecount > 0); so->so_usecount--; - if (so->so_usecount != 1 || - (inp->inp_wantcnt > 0 && + if (so->so_usecount != 1 || + (inp->inp_wantcnt > 0 && inp->inp_wantcnt != WNT_STOPUSING)) { - /* - * There is an extra wantcount or usecount - * that must have been added when the socket - * was unlocked. This socket will have to be + /* + * There is an extra wantcount or usecount + * that must have been added when the socket + * was unlocked. This socket will have to be * garbage collected later */ - tcp_unlock(so, 1, 0); + socket_unlock(so, 1); } else { - /* Drop the reference held for this function */ + VERIFY(so->so_usecount > 0); so->so_usecount--; in_pcbdispose(inp); @@ -5197,10 +6800,8 @@ found_victim: } tcpstat.tcps_drops++; - tcp_lock(head, 0, 0); - head->so_incqlen--; - head->so_qlen--; - return(1); + socket_lock(head, 0); + return 1; } /* Set background congestion control on a socket */ @@ -5214,7 +6815,11 @@ tcp_set_background_cc(struct socket *so) void tcp_set_foreground_cc(struct socket *so) { - tcp_set_new_cc(so, TCP_CC_ALGO_NEWRENO_INDEX); + if (tcp_use_newreno) { + tcp_set_new_cc(so, TCP_CC_ALGO_NEWRENO_INDEX); + } else { + tcp_set_new_cc(so, TCP_CC_ALGO_CUBIC_INDEX); + } } static void @@ -5224,35 +6829,29 @@ tcp_set_new_cc(struct socket *so, uint16_t cc_index) struct tcpcb *tp = intotcpcb(inp); u_char old_cc_index = 0; if (tp->tcp_cc_index != cc_index) { - old_cc_index = tp->tcp_cc_index; - if (CC_ALGO(tp)->cleanup != NULL) + if (CC_ALGO(tp)->cleanup != NULL) { CC_ALGO(tp)->cleanup(tp); + } tp->tcp_cc_index = cc_index; - /* Decide if the connection is just starting or if - * we have sent some packets on it. - */ - if (tp->snd_nxt > tp->iss) { - /* Already sent some packets */ - if (CC_ALGO(tp)->switch_to != NULL) - CC_ALGO(tp)->switch_to(tp, old_cc_index); - } else { - if (CC_ALGO(tp)->init != NULL) - CC_ALGO(tp)->init(tp); - } - DTRACE_TCP5(cc, void, NULL, struct inpcb *, inp, - struct tcpcb *, tp, struct tcphdr *, NULL, - int32_t, TCP_CC_CHANGE_ALGO); + tcp_cc_allocate_state(tp); + + if (CC_ALGO(tp)->switch_to != NULL) { + CC_ALGO(tp)->switch_to(tp, old_cc_index); + } + + tcp_ccdbg_trace(tp, NULL, TCP_CC_CHANGE_ALGO); } } void tcp_set_recv_bg(struct socket *so) { - if (!IS_TCP_RECV_BG(so)) - so->so_traffic_mgt_flags |= TRAFFIC_MGT_TCP_RECVBG; + if (!IS_TCP_RECV_BG(so)) { + so->so_flags1 |= SOF1_TRAFFIC_MGT_TCP_RECVBG; + } /* Unset Large Receive Offload on background sockets */ so_set_lro(so, SO_TC_BK); @@ -5261,11 +6860,12 @@ tcp_set_recv_bg(struct socket *so) void tcp_clear_recv_bg(struct socket *so) { - if (IS_TCP_RECV_BG(so)) - so->so_traffic_mgt_flags &= ~(TRAFFIC_MGT_TCP_RECVBG); + if (IS_TCP_RECV_BG(so)) { + so->so_flags1 &= ~(SOF1_TRAFFIC_MGT_TCP_RECVBG); + } - /* - * Set/unset use of Large Receive Offload depending on + /* + * Set/unset use of Large Receive Offload depending on * the traffic class */ so_set_lro(so, so->so_traffic_class); @@ -5279,11 +6879,12 @@ inp_fc_unthrottle_tcp(struct inpcb *inp) * Back off the slow-start threshold and enter * congestion avoidance phase */ - if (CC_ALGO(tp)->pre_fr != NULL) + if (CC_ALGO(tp)->pre_fr != NULL) { CC_ALGO(tp)->pre_fr(tp); + } tp->snd_cwnd = tp->snd_ssthresh; - + tp->t_flagsext &= ~TF_CWND_NONVALIDATED; /* * Restart counting for ABC as we changed the * congestion window just now. @@ -5291,11 +6892,11 @@ inp_fc_unthrottle_tcp(struct inpcb *inp) tp->t_bytes_acked = 0; /* Reset retransmit shift as we know that the reason - * for delay in sending a packet is due to flow + * for delay in sending a packet is due to flow * control on the outgoing interface. There is no need * to backoff retransmit timer. */ - tp->t_rxtshift = 0; + TCP_RESET_REXMT_STATE(tp); /* * Start the output stream again. Since we are @@ -5304,57 +6905,33 @@ inp_fc_unthrottle_tcp(struct inpcb *inp) */ tcp_output(tp); } - + static int tcp_getstat SYSCTL_HANDLER_ARGS { #pragma unused(oidp, arg1, arg2) int error; + struct tcpstat *stat; + stat = &tcpstat; +#if !CONFIG_EMBEDDED + struct tcpstat zero_stat; + + if (tcp_disable_access_to_stats && + !kauth_cred_issuser(kauth_cred_get())) { + bzero(&zero_stat, sizeof(zero_stat)); + stat = &zero_stat; + } - proc_t caller = PROC_NULL; - proc_t caller_parent = PROC_NULL; - char command_name[MAXCOMLEN + 1] = ""; - char parent_name[MAXCOMLEN + 1] = ""; - - if ((caller = proc_self()) != PROC_NULL) { - /* get process name */ - strlcpy(command_name, caller->p_comm, sizeof(command_name)); - - /* get parent process name if possible */ - if ((caller_parent = proc_find(caller->p_ppid)) != PROC_NULL) { - strlcpy(parent_name, caller_parent->p_comm, - sizeof(parent_name)); - proc_rele(caller_parent); - } - - if ((escape_str(command_name, strlen(command_name), - sizeof(command_name)) == 0) && - (escape_str(parent_name, strlen(parent_name), - sizeof(parent_name)) == 0)) { - kern_asl_msg(LOG_DEBUG, "messagetracer", - 5, - "com.apple.message.domain", - "com.apple.kernel.tcpstat", /* 1 */ - "com.apple.message.signature", - "tcpstat", /* 2 */ - "com.apple.message.signature2", command_name, /* 3 */ - "com.apple.message.signature3", parent_name, /* 4 */ - "com.apple.message.summarize", "YES", /* 5 */ - NULL); - } - } - if (caller != PROC_NULL) - proc_rele(caller); +#endif /* !CONFIG_EMBEDDED */ if (req->oldptr == 0) { - req->oldlen= (size_t)sizeof(struct tcpstat); + req->oldlen = (size_t)sizeof(struct tcpstat); } - error = SYSCTL_OUT(req, &tcpstat, MIN(sizeof (tcpstat), req->oldlen)); - - return (error); + error = SYSCTL_OUT(req, stat, MIN(sizeof(tcpstat), req->oldlen)); + return error; } /* @@ -5370,8 +6947,12 @@ tcp_input_checksum(int af, struct mbuf *m, struct tcphdr *th, int off, int tlen) struct ip *ip = mtod(m, struct ip *); struct ipovly *ipov = (struct ipovly *)ip; - if (m->m_pkthdr.pkt_flags & PKTF_SW_LRO_DID_CSUM) - return (0); + if (m->m_pkthdr.pkt_flags & PKTF_SW_LRO_DID_CSUM) { + return 0; + } + + /* ip_stripoptions() must have been called before we get here */ + ASSERT((ip->ip_hl << 2) == sizeof(*ip)); if ((hwcksum_rx || (ifp->if_flags & IFF_LOOPBACK) || (m->m_pkthdr.pkt_flags & PKTF_LOOP)) && @@ -5379,33 +6960,59 @@ tcp_input_checksum(int af, struct mbuf *m, struct tcphdr *th, int off, int tlen) if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) { th->th_sum = m->m_pkthdr.csum_rx_val; } else { - uint16_t sum = m->m_pkthdr.csum_rx_val; - uint16_t start = m->m_pkthdr.csum_rx_start; + uint32_t sum = m->m_pkthdr.csum_rx_val; + uint32_t start = m->m_pkthdr.csum_rx_start; + int32_t trailer = (m_pktlen(m) - (off + tlen)); /* * Perform 1's complement adjustment of octets * that got included/excluded in the hardware- * calculated checksum value. Ignore cases - * where the value includes or excludes the IP - * header span, as the sum for those octets - * would already be 0xffff and thus no-op. + * where the value already includes the entire + * IP header span, as the sum for those octets + * would already be 0 by the time we get here; + * IP has already performed its header checksum + * checks. If we do need to adjust, restore + * the original fields in the IP header when + * computing the adjustment value. Also take + * care of any trailing bytes and subtract out + * their partial sum. */ + ASSERT(trailer >= 0); if ((m->m_pkthdr.csum_flags & CSUM_PARTIAL) && - start != 0 && (off - start) != off) { -#if BYTE_ORDER != BIG_ENDIAN + ((start != 0 && start != off) || trailer)) { + uint32_t swbytes = (uint32_t)trailer; + if (start < off) { + ip->ip_len += sizeof(*ip); +#if BYTE_ORDER != BIG_ENDIAN HTONS(ip->ip_len); HTONS(ip->ip_off); +#endif /* BYTE_ORDER != BIG_ENDIAN */ } -#endif /* callee folds in sum */ - sum = m_adj_sum16(m, start, off, sum); -#if BYTE_ORDER != BIG_ENDIAN + sum = m_adj_sum16(m, start, off, + tlen, sum); + if (off > start) { + swbytes += (off - start); + } else { + swbytes += (start - off); + } + if (start < off) { +#if BYTE_ORDER != BIG_ENDIAN NTOHS(ip->ip_off); NTOHS(ip->ip_len); +#endif /* BYTE_ORDER != BIG_ENDIAN */ + ip->ip_len -= sizeof(*ip); + } + + if (swbytes != 0) { + tcp_in_cksum_stats(swbytes); + } + if (trailer != 0) { + m_adj(m, -trailer); } -#endif } /* callee folds in sum */ @@ -5419,16 +7026,16 @@ tcp_input_checksum(int af, struct mbuf *m, struct tcphdr *th, int off, int tlen) int len; char b[9]; - bcopy(ipov->ih_x1, b, sizeof (ipov->ih_x1)); - bzero(ipov->ih_x1, sizeof (ipov->ih_x1)); + bcopy(ipov->ih_x1, b, sizeof(ipov->ih_x1)); + bzero(ipov->ih_x1, sizeof(ipov->ih_x1)); ip_sum = ipov->ih_len; ipov->ih_len = (u_short)tlen; #if BYTE_ORDER != BIG_ENDIAN HTONS(ipov->ih_len); #endif - len = sizeof (struct ip) + tlen; + len = sizeof(struct ip) + tlen; th->th_sum = in_cksum(m, len); - bcopy(b, ipov->ih_x1, sizeof (ipov->ih_x1)); + bcopy(b, ipov->ih_x1, sizeof(ipov->ih_x1)); ipov->ih_len = ip_sum; tcp_in_cksum_stats(len); @@ -5439,8 +7046,9 @@ tcp_input_checksum(int af, struct mbuf *m, struct tcphdr *th, int off, int tlen) case AF_INET6: { struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *); - if (m->m_pkthdr.pkt_flags & PKTF_SW_LRO_DID_CSUM) - return (0); + if (m->m_pkthdr.pkt_flags & PKTF_SW_LRO_DID_CSUM) { + return 0; + } if ((hwcksum_rx || (ifp->if_flags & IFF_LOOPBACK) || (m->m_pkthdr.pkt_flags & PKTF_LOOP)) && @@ -5448,21 +7056,26 @@ tcp_input_checksum(int af, struct mbuf *m, struct tcphdr *th, int off, int tlen) if (m->m_pkthdr.csum_flags & CSUM_PSEUDO_HDR) { th->th_sum = m->m_pkthdr.csum_rx_val; } else { - uint16_t sum = m->m_pkthdr.csum_rx_val; - uint16_t start = m->m_pkthdr.csum_rx_start; + uint32_t sum = m->m_pkthdr.csum_rx_val; + uint32_t start = m->m_pkthdr.csum_rx_start; + int32_t trailer = (m_pktlen(m) - (off + tlen)); /* * Perform 1's complement adjustment of octets * that got included/excluded in the hardware- - * calculated checksum value. + * calculated checksum value. Also take care + * of any trailing bytes and subtract out their + * partial sum. */ + ASSERT(trailer >= 0); if ((m->m_pkthdr.csum_flags & CSUM_PARTIAL) && - start != off) { - uint16_t s, d; + (start != off || trailer != 0)) { + uint16_t s = 0, d = 0; + uint32_t swbytes = (uint32_t)trailer; if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) { s = ip6->ip6_src.s6_addr16[1]; - ip6->ip6_src.s6_addr16[1] = 0 ; + ip6->ip6_src.s6_addr16[1] = 0; } if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) { d = ip6->ip6_dst.s6_addr16[1]; @@ -5470,17 +7083,32 @@ tcp_input_checksum(int af, struct mbuf *m, struct tcphdr *th, int off, int tlen) } /* callee folds in sum */ - sum = m_adj_sum16(m, start, off, sum); + sum = m_adj_sum16(m, start, off, + tlen, sum); + if (off > start) { + swbytes += (off - start); + } else { + swbytes += (start - off); + } - if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) + if (IN6_IS_SCOPE_EMBED(&ip6->ip6_src)) { ip6->ip6_src.s6_addr16[1] = s; - if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) + } + if (IN6_IS_SCOPE_EMBED(&ip6->ip6_dst)) { ip6->ip6_dst.s6_addr16[1] = d; + } + + if (swbytes != 0) { + tcp_in6_cksum_stats(swbytes); + } + if (trailer != 0) { + m_adj(m, -trailer); + } } th->th_sum = in6_pseudo( - &ip6->ip6_src, &ip6->ip6_dst, - sum + htonl(tlen + IPPROTO_TCP)); + &ip6->ip6_src, &ip6->ip6_dst, + sum + htonl(tlen + IPPROTO_TCP)); } th->th_sum ^= 0xffff; } else { @@ -5498,14 +7126,16 @@ tcp_input_checksum(int af, struct mbuf *m, struct tcphdr *th, int off, int tlen) if (th->th_sum != 0) { tcpstat.tcps_rcvbadsum++; IF_TCP_STATINC(ifp, badformat); - return (-1); + return -1; } - return (0); + return 0; } -SYSCTL_PROC(_net_inet_tcp, TCPCTL_STATS, stats, CTLFLAG_RD | CTLFLAG_LOCKED, 0, 0, - tcp_getstat, "S,tcpstat", "TCP statistics (struct tcpstat, netinet/tcp_var.h)"); + +SYSCTL_PROC(_net_inet_tcp, TCPCTL_STATS, stats, + CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED, 0, 0, tcp_getstat, + "S,tcpstat", "TCP statistics (struct tcpstat, netinet/tcp_var.h)"); static int sysctl_rexmtthresh SYSCTL_HANDLER_ARGS @@ -5515,22 +7145,25 @@ sysctl_rexmtthresh SYSCTL_HANDLER_ARGS int error, val = tcprexmtthresh; error = sysctl_handle_int(oidp, &val, 0, req); - if (error || !req->newptr) - return (error); + if (error || !req->newptr) { + return error; + } /* * Constrain the number of duplicate ACKs - * to consider for TCP fast retransmit + * to consider for TCP fast retransmit * to either 2 or 3 */ - if (val < 2 || val > 3) - return (EINVAL); + if (val < 2 || val > 3) { + return EINVAL; + } - tcprexmtthresh = val; + tcprexmtthresh = val; - return (0); + return 0; } -SYSCTL_PROC(_net_inet_tcp, OID_AUTO, rexmt_thresh, CTLTYPE_INT|CTLFLAG_RW | CTLFLAG_LOCKED, - &tcprexmtthresh, 0, &sysctl_rexmtthresh, "I", "Duplicate ACK Threshold for Fast Retransmit"); +SYSCTL_PROC(_net_inet_tcp, OID_AUTO, rexmt_thresh, CTLTYPE_INT | CTLFLAG_RW | + CTLFLAG_LOCKED, &tcprexmtthresh, 0, &sysctl_rexmtthresh, "I", + "Duplicate ACK Threshold for Fast Retransmit");