/*
- * Copyright (c) 2000-2013 Apple Inc. All rights reserved.
+ * Copyright (c) 2000-2015 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
#endif
#include <netinet/tcp.h>
#define TCPOUTFLAGS
+#include <netinet/tcp_cache.h>
#include <netinet/tcp_fsm.h>
#include <netinet/tcp_seq.h>
#include <netinet/tcp_timer.h>
#include <netinet/mptcp_opt.h>
#endif
+#include <corecrypto/ccaes.h>
+
#define DBG_LAYER_BEG NETDBG_CODE(DBG_NETTCP, 1)
#define DBG_LAYER_END NETDBG_CODE(DBG_NETTCP, 3)
#define DBG_FNC_TCP_OUTPUT NETDBG_CODE(DBG_NETTCP, (4 << 8) | 1)
int path_mtu_discovery = 1;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, path_mtu_discovery, CTLFLAG_RW | CTLFLAG_LOCKED,
- &path_mtu_discovery, 1, "Enable Path MTU Discovery");
+SYSCTL_INT(_net_inet_tcp, OID_AUTO, path_mtu_discovery,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &path_mtu_discovery, 1,
+ "Enable Path MTU Discovery");
int ss_fltsz = 1;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, slowstart_flightsize, CTLFLAG_RW | CTLFLAG_LOCKED,
- &ss_fltsz, 1, "Slow start flight size");
+SYSCTL_INT(_net_inet_tcp, OID_AUTO, slowstart_flightsize,
+ CTLFLAG_RW | CTLFLAG_LOCKED,&ss_fltsz, 1,
+ "Slow start flight size");
int ss_fltsz_local = 8; /* starts with eight segments max */
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, local_slowstart_flightsize, CTLFLAG_RW | CTLFLAG_LOCKED,
- &ss_fltsz_local, 1, "Slow start flight size for local networks");
+SYSCTL_INT(_net_inet_tcp, OID_AUTO, local_slowstart_flightsize,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &ss_fltsz_local, 1,
+ "Slow start flight size for local networks");
int tcp_do_tso = 1;
SYSCTL_INT(_net_inet_tcp, OID_AUTO, tso, CTLFLAG_RW | CTLFLAG_LOCKED,
&tcp_do_tso, 0, "Enable TCP Segmentation Offload");
+static int
+sysctl_change_ecn_setting SYSCTL_HANDLER_ARGS
+{
+#pragma unused(oidp, arg1, arg2)
+ int i, err = 0, changed = 0;
+ struct ifnet *ifp;
+
+ err = sysctl_io_number(req, tcp_ecn_outbound, sizeof(int32_t),
+ &i, &changed);
+ if (err != 0 || req->newptr == USER_ADDR_NULL)
+ return(err);
+
+ if (changed) {
+ if ((tcp_ecn_outbound == 0 || tcp_ecn_outbound == 1) &&
+ (i == 0 || i == 1)) {
+ tcp_ecn_outbound = i;
+ return(err);
+ }
+ if (tcp_ecn_outbound == 2 && (i == 0 || i == 1)) {
+ /*
+ * Reset ECN enable flags on non-cellular
+ * interfaces so that the system default will take
+ * over
+ */
+ ifnet_head_lock_shared();
+ TAILQ_FOREACH(ifp, &ifnet_head, if_link) {
+ if (!IFNET_IS_CELLULAR(ifp)) {
+ ifnet_lock_exclusive(ifp);
+ ifp->if_eflags &= ~IFEF_ECN_DISABLE;
+ ifp->if_eflags &= ~IFEF_ECN_ENABLE;
+ ifnet_lock_done(ifp);
+ }
+ }
+ ifnet_head_done();
+ } else {
+ /*
+ * Set ECN enable flags on non-cellular
+ * interfaces
+ */
+ ifnet_head_lock_shared();
+ TAILQ_FOREACH(ifp, &ifnet_head, if_link) {
+ if (!IFNET_IS_CELLULAR(ifp)) {
+ ifnet_lock_exclusive(ifp);
+ ifp->if_eflags |= IFEF_ECN_ENABLE;
+ ifp->if_eflags &= ~IFEF_ECN_DISABLE;
+ ifnet_lock_done(ifp);
+ }
+ }
+ ifnet_head_done();
+ }
+ tcp_ecn_outbound = i;
+ }
+ /* Change the other one too as the work is done */
+ if (i == 2 || tcp_ecn_inbound == 2)
+ tcp_ecn_inbound = i;
+ return (err);
+}
-int tcp_ecn_outbound = 0;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, ecn_initiate_out, CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_ecn_outbound,
- 0, "Initiate ECN for outbound connections");
+int tcp_ecn_outbound = 2;
+SYSCTL_PROC(_net_inet_tcp, OID_AUTO, ecn_initiate_out,
+ CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_ecn_outbound, 0,
+ sysctl_change_ecn_setting, "IU",
+ "Initiate ECN for outbound connections");
-int tcp_ecn_inbound = 0;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, ecn_negotiate_in, CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_ecn_inbound,
- 0, "Allow ECN negotiation for inbound connections");
+int tcp_ecn_inbound = 2;
+SYSCTL_PROC(_net_inet_tcp, OID_AUTO, ecn_negotiate_in,
+ CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_ecn_inbound, 0,
+ sysctl_change_ecn_setting, "IU",
+ "Initiate ECN for inbound connections");
int tcp_packet_chaining = 50;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, packetchain, CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_packet_chaining,
- 0, "Enable TCP output packet chaining");
+SYSCTL_INT(_net_inet_tcp, OID_AUTO, packetchain,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_packet_chaining, 0,
+ "Enable TCP output packet chaining");
int tcp_output_unlocked = 1;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, socket_unlocked_on_output, CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_output_unlocked,
- 0, "Unlock TCP when sending packets down to IP");
+SYSCTL_INT(_net_inet_tcp, OID_AUTO, socket_unlocked_on_output,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_output_unlocked, 0,
+ "Unlock TCP when sending packets down to IP");
int tcp_do_rfc3390 = 1;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, rfc3390, CTLFLAG_RW | CTLFLAG_LOCKED,
- &tcp_do_rfc3390, 1, "Calculate intial slowstart cwnd depending on MSS");
+SYSCTL_INT(_net_inet_tcp, OID_AUTO, rfc3390,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_do_rfc3390, 1,
+ "Calculate intial slowstart cwnd depending on MSS");
int tcp_min_iaj_win = MIN_IAJ_WIN;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, min_iaj_win, CTLFLAG_RW | CTLFLAG_LOCKED,
- &tcp_min_iaj_win, 1, "Minimum recv win based on inter-packet arrival jitter");
+SYSCTL_INT(_net_inet_tcp, OID_AUTO, min_iaj_win,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_min_iaj_win, 1,
+ "Minimum recv win based on inter-packet arrival jitter");
int tcp_acc_iaj_react_limit = ACC_IAJ_REACT_LIMIT;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, acc_iaj_react_limit, CTLFLAG_RW | CTLFLAG_LOCKED,
- &tcp_acc_iaj_react_limit, 1, "Accumulated IAJ when receiver starts to react");
+SYSCTL_INT(_net_inet_tcp, OID_AUTO, acc_iaj_react_limit,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_acc_iaj_react_limit, 1,
+ "Accumulated IAJ when receiver starts to react");
uint32_t tcp_do_autosendbuf = 1;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, doautosndbuf, CTLFLAG_RW | CTLFLAG_LOCKED,
- &tcp_do_autosendbuf, 1, "Enable send socket buffer auto-tuning");
+SYSCTL_INT(_net_inet_tcp, OID_AUTO, doautosndbuf,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_do_autosendbuf, 1,
+ "Enable send socket buffer auto-tuning");
uint32_t tcp_autosndbuf_inc = 8 * 1024;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, autosndbufinc, CTLFLAG_RW | CTLFLAG_LOCKED,
- &tcp_autosndbuf_inc, 1, "Increment in send socket bufffer size");
+SYSCTL_INT(_net_inet_tcp, OID_AUTO, autosndbufinc,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_autosndbuf_inc, 1,
+ "Increment in send socket bufffer size");
uint32_t tcp_autosndbuf_max = 512 * 1024;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, autosndbufmax, CTLFLAG_RW | CTLFLAG_LOCKED,
- &tcp_autosndbuf_max, 1, "Maximum send socket buffer size");
+SYSCTL_INT(_net_inet_tcp, OID_AUTO, autosndbufmax,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_autosndbuf_max, 1,
+ "Maximum send socket buffer size");
uint32_t tcp_prioritize_acks = 1;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, ack_prioritize, CTLFLAG_RW | CTLFLAG_LOCKED,
- &tcp_prioritize_acks, 1, "Prioritize pure acks");
+SYSCTL_INT(_net_inet_tcp, OID_AUTO, ack_prioritize,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_prioritize_acks, 1,
+ "Prioritize pure acks");
uint32_t tcp_use_rtt_recvbg = 1;
-SYSCTL_INT(_net_inet_tcp, OID_AUTO, rtt_recvbg,
- CTLFLAG_RW | CTLFLAG_LOCKED,
- &tcp_use_rtt_recvbg, 1, "Use RTT for bg recv algorithm");
+SYSCTL_INT(_net_inet_tcp, OID_AUTO, rtt_recvbg,
+ CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_use_rtt_recvbg, 1,
+ "Use RTT for bg recv algorithm");
uint32_t tcp_recv_throttle_minwin = 16 * 1024;
SYSCTL_INT(_net_inet_tcp, OID_AUTO, recv_throttle_minwin,
- CTLFLAG_RW | CTLFLAG_LOCKED,
- &tcp_recv_throttle_minwin, 1, "Minimum recv win for throttling");
+ CTLFLAG_RW | CTLFLAG_LOCKED, &tcp_recv_throttle_minwin, 1,
+ "Minimum recv win for throttling");
+int32_t tcp_enable_tlp = 1;
+SYSCTL_INT(_net_inet_tcp, OID_AUTO, enable_tlp,
+ CTLFLAG_RW | CTLFLAG_LOCKED,
+ &tcp_enable_tlp, 1, "Enable Tail loss probe");
static int32_t packchain_newlist = 0;
static int32_t packchain_looped = 0;
extern u_int32_t dlil_filter_disable_tso_count;
extern u_int32_t kipf_count;
extern int tcp_recv_bg;
-extern int maxseg_unacked;
static int tcp_ip_output(struct socket *, struct tcpcb *, struct mbuf *, int,
struct mbuf *, int, int, int32_t, boolean_t);
-
-extern uint32_t get_base_rtt(struct tcpcb *tp);
static struct mbuf* tcp_send_lroacks(struct tcpcb *tp, struct mbuf *m, struct tcphdr *th);
static int tcp_recv_throttle(struct tcpcb *tp);
+static int32_t tcp_tfo_check(struct tcpcb *tp, int32_t len)
+{
+ struct socket *so = tp->t_inpcb->inp_socket;
+ unsigned int optlen = 0;
+ unsigned int cookie_len;
+
+ if (tp->t_flags & TF_NOOPT)
+ goto fallback;
+
+ if (!tcp_heuristic_do_tfo(tp))
+ goto fallback;
+
+ optlen += TCPOLEN_MAXSEG;
+
+ if (tp->t_flags & TF_REQ_SCALE)
+ optlen += 4;
+
+#if MPTCP
+ if ((so->so_flags & SOF_MP_SUBFLOW) && mptcp_enable &&
+ tp->t_rxtshift <= mptcp_mpcap_retries)
+ optlen += sizeof(struct mptcp_mpcapable_opt_common) + sizeof(mptcp_key_t);
+#endif /* MPTCP */
+
+ if (tp->t_flags & TF_REQ_TSTMP)
+ optlen += TCPOLEN_TSTAMP_APPA;
+
+ if (SACK_ENABLED(tp))
+ optlen += TCPOLEN_SACK_PERMITTED;
+
+ /* Now, decide whether to use TFO or not */
+
+ /* Don't even bother trying if there is no space at all... */
+ if (MAX_TCPOPTLEN - optlen < TCPOLEN_FASTOPEN_REQ)
+ goto fallback;
+
+ cookie_len = tcp_cache_get_cookie_len(tp);
+ if (cookie_len == 0)
+ /* No cookie, so we request one */
+ return (0);
+
+ /* Do not send SYN+data if there is more in the queue than MSS */
+ if (so->so_snd.sb_cc > (tp->t_maxopd - MAX_TCPOPTLEN))
+ goto fallback;
+
+ /* Ok, everything looks good. We can go on and do TFO */
+ return (len);
+
+fallback:
+ tp->t_flagsext &= ~TF_FASTOPEN;
+ return (0);
+}
+
+/* Returns the number of bytes written to the TCP option-space */
+static unsigned
+tcp_tfo_write_cookie_rep(struct tcpcb *tp, unsigned optlen, u_char *opt)
+{
+ u_char out[CCAES_BLOCK_SIZE];
+ unsigned ret = 0;
+ u_char *bp;
+
+ if ((MAX_TCPOPTLEN - optlen) <
+ (TCPOLEN_FASTOPEN_REQ + TFO_COOKIE_LEN_DEFAULT))
+ return (ret);
+
+ tcp_tfo_gen_cookie(tp->t_inpcb, out, sizeof(out));
+
+ bp = opt + optlen;
+
+ *bp++ = TCPOPT_FASTOPEN;
+ *bp++ = 2 + TFO_COOKIE_LEN_DEFAULT;
+ memcpy(bp, out, TFO_COOKIE_LEN_DEFAULT);
+ ret += 2 + TFO_COOKIE_LEN_DEFAULT;
+
+ tp->t_tfo_stats |= TFO_S_COOKIE_SENT;
+ tcpstat.tcps_tfo_cookie_sent++;
+
+ return (ret);
+}
+
+static unsigned
+tcp_tfo_write_cookie(struct tcpcb *tp, unsigned optlen, int32_t *len,
+ u_char *opt)
+{
+ u_int8_t tfo_len = MAX_TCPOPTLEN - optlen - TCPOLEN_FASTOPEN_REQ;
+ unsigned ret = 0;
+ int res;
+ u_char *bp;
+
+ bp = opt + optlen;
+
+ /*
+ * The cookie will be copied in the appropriate place within the
+ * TCP-option space. That way we avoid the need for an intermediate
+ * variable.
+ */
+ res = tcp_cache_get_cookie(tp, bp + TCPOLEN_FASTOPEN_REQ, &tfo_len);
+ if (res == 0) {
+ *bp++ = TCPOPT_FASTOPEN;
+ *bp++ = TCPOLEN_FASTOPEN_REQ;
+ ret += TCPOLEN_FASTOPEN_REQ;
+
+ tp->t_tfo_flags |= TFO_F_COOKIE_REQ;
+
+ tp->t_tfo_stats |= TFO_S_COOKIE_REQ;
+ tcpstat.tcps_tfo_cookie_req++;
+ } else {
+ *bp++ = TCPOPT_FASTOPEN;
+ *bp++ = TCPOLEN_FASTOPEN_REQ + tfo_len;
+
+ ret += TCPOLEN_FASTOPEN_REQ + tfo_len;
+
+ tp->t_tfo_flags |= TFO_F_COOKIE_SENT;
+
+ /* If there is some data, let's track it */
+ if (*len) {
+ tp->t_tfo_stats |= TFO_S_SYN_DATA_SENT;
+ tcpstat.tcps_tfo_syn_data_sent++;
+ }
+ }
+
+ return (ret);
+}
+
+static inline bool
+tcp_send_ecn_flags_on_syn(struct tcpcb *tp, struct socket *so)
+{
+ return(!((tp->ecn_flags & TE_SETUPSENT) ||
+ (so->so_flags & SOF_MP_SUBFLOW) ||
+ (tp->t_flagsext & TF_FASTOPEN)));
+}
+
+#define TCP_ECN_SETUP_PERCENTAGE_MAX 5
+void
+tcp_set_ecn(struct tcpcb *tp, struct ifnet *ifp)
+{
+ boolean_t inbound;
+
+ /*
+ * Socket option has precedence
+ */
+ if (tp->ecn_flags & TE_ECN_MODE_ENABLE) {
+ tp->ecn_flags |= TE_ENABLE_ECN;
+ goto check_heuristic;
+ }
+
+ if (tp->ecn_flags & TE_ECN_MODE_DISABLE) {
+ tp->ecn_flags &= ~TE_ENABLE_ECN;
+ return;
+ }
+ /*
+ * Per interface setting comes next
+ */
+ if (ifp != NULL) {
+ if (ifp->if_eflags & IFEF_ECN_ENABLE) {
+ tp->ecn_flags |= TE_ENABLE_ECN;
+ goto check_heuristic;
+ }
+
+ if (ifp->if_eflags & IFEF_ECN_DISABLE) {
+ tp->ecn_flags &= ~TE_ENABLE_ECN;
+ return;
+ }
+ }
+ /*
+ * System wide settings come last
+ */
+ inbound = (tp->t_inpcb->inp_socket->so_head != NULL);
+ if ((inbound && tcp_ecn_inbound == 1) ||
+ (!inbound && tcp_ecn_outbound == 1)) {
+ tp->ecn_flags |= TE_ENABLE_ECN;
+ goto check_heuristic;
+ } else {
+ tp->ecn_flags &= ~TE_ENABLE_ECN;
+ }
+
+ return;
+
+check_heuristic:
+ if (!tcp_heuristic_do_ecn(tp))
+ tp->ecn_flags &= ~TE_ENABLE_ECN;
+
+ /*
+ * If the interface setting, system-level setting and heuristics
+ * allow to enable ECN, randomly select 5% of connections to
+ * enable it
+ */
+ if ((tp->ecn_flags & (TE_ECN_MODE_ENABLE | TE_ECN_MODE_DISABLE
+ | TE_ENABLE_ECN)) == TE_ENABLE_ECN) {
+ /*
+ * Use the random value in iss for randomizing
+ * this selection
+ */
+ if ((tp->iss % 100) >= TCP_ECN_SETUP_PERCENTAGE_MAX)
+ tp->ecn_flags &= ~TE_ENABLE_ECN;
+ }
+}
+
/*
* Tcp output routine: figure out what should be sent and send it.
*
struct socket *so = inp->inp_socket;
int32_t len, recwin, sendwin, off;
int flags, error;
- register struct mbuf *m;
+ struct mbuf *m;
struct ip *ip = NULL;
- register struct ipovly *ipov = NULL;
+ struct ipovly *ipov = NULL;
#if INET6
struct ip6_hdr *ip6 = NULL;
#endif /* INET6 */
- register struct tcphdr *th;
+ struct tcphdr *th;
u_char opt[TCP_MAXOLEN];
unsigned ipoptlen, optlen, hdrlen;
int idle, sendalot, lost = 0;
int i, sack_rxmit;
int tso = 0;
int sack_bytes_rxmt;
+ tcp_seq old_snd_nxt = 0;
struct sackhole *p;
#if IPSEC
unsigned ipsec_optlen = 0;
#endif /* IPSEC */
- int last_off = 0;
- int m_off = 0;
int idle_time = 0;
- struct mbuf *m_lastm = NULL;
- struct mbuf *m_head = NULL;
struct mbuf *packetlist = NULL;
struct mbuf *tp_inp_options = inp->inp_depend4.inp4_options;
#if INET6
u_int8_t *finp = NULL;
u_int32_t *sseqp = NULL;
u_int64_t dss_val = 0;
- int mptcp_acknow = 0;
+ boolean_t mptcp_acknow = FALSE;
+ boolean_t early_data_sent = FALSE;
#endif /* MPTCP */
boolean_t cell = FALSE;
boolean_t wifi = FALSE;
+ boolean_t wired = FALSE;
+ boolean_t sack_rescue_rxt = FALSE;
/*
* Determine length of data that should be transmitted,
*/
idle_time = tcp_now - tp->t_rcvtime;
if (idle && idle_time >= TCP_IDLETIMEOUT(tp)) {
- if (CC_ALGO(tp)->after_idle != NULL)
+ if (CC_ALGO(tp)->after_idle != NULL &&
+ (tp->tcp_cc_index != TCP_CC_ALGO_CUBIC_INDEX ||
+ idle_time >= TCP_CC_CWND_NONVALIDATED_PERIOD)) {
CC_ALGO(tp)->after_idle(tp);
- DTRACE_TCP5(cc, void, NULL, struct inpcb *, inp,
- struct tcpcb *, tp, struct tcphdr *, NULL,
- int32_t, TCP_CC_IDLE_TIMEOUT);
+ tcp_ccdbg_trace(tp, NULL, TCP_CC_IDLE_TIMEOUT);
+ }
+
+ /*
+ * Do some other tasks that need to be done after
+ * idle time
+ */
+ if (!SLIST_EMPTY(&tp->t_rxt_segments))
+ tcp_rxtseg_clean(tp);
+
+ /* If stretch ack was auto-disabled, re-evaluate it */
+ tcp_cc_after_idle_stretchack(tp);
}
tp->t_flags &= ~TF_LASTIDLE;
if (idle) {
/* Disable TSO for the socket until we know more */
tp->t_flags &= ~TF_TSO;
+ soif2kcl(so, FALSE);
+
if (isipv6) {
ia6 = ifa_foraddr6(&inp->in6p_laddr);
if (ia6 != NULL)
return(EADDRNOTAVAIL);
}
- /* set Retransmit timer if it wasn't set
+ /* Set retransmit timer if it wasn't set,
* reset Persist timer and shift register as the
* advertised peer window may not be valid anymore
*/
if (!tp->t_timer[TCPT_REXMT]) {
- tp->t_timer[TCPT_REXMT] = OFFSET_FROM_START(tp, tp->t_rxtcur);
+ tp->t_timer[TCPT_REXMT] =
+ OFFSET_FROM_START(tp, tp->t_rxtcur);
if (tp->t_timer[TCPT_PERSIST]) {
tp->t_timer[TCPT_PERSIST] = 0;
tp->t_rxtshift = 0;
if (so->so_flags & SOF_NOADDRAVAIL) {
tcp_drop(tp, EADDRNOTAVAIL);
return(EADDRNOTAVAIL);
- }
- else {
+ } else {
tcp_check_timer_state(tp);
return(0); /* silently ignore, keep data in socket: address may be back */
}
if ((ifp = rt->rt_ifp) != NULL) {
somultipages(so, (ifp->if_hwassist & IFNET_MULTIPAGES));
tcp_set_tso(tp, ifp);
+ soif2kcl(so, (ifp->if_eflags & IFEF_2KCL));
+ tcp_set_ecn(tp, ifp);
}
if (rt->rt_flags & RTF_UP)
RT_GENID_SYNC(rt);
* See if we should do MTU discovery. Don't do it if:
* 1) it is disabled via the sysctl
* 2) the route isn't up
- * 3) the MTU is locked (if it is, then discovery has been
- * disabled)
+ * 3) the MTU is locked (if it is, then discovery
+ * has been disabled)
*/
if (!path_mtu_discovery || ((rt != NULL) &&
- (!(rt->rt_flags & RTF_UP) || (rt->rt_rmx.rmx_locks & RTV_MTU))))
+ (!(rt->rt_flags & RTF_UP) ||
+ (rt->rt_rmx.rmx_locks & RTV_MTU))))
tp->t_flags &= ~TF_PMTUD;
else
tp->t_flags |= TF_PMTUD;
if (rt != NULL) {
cell = IFNET_IS_CELLULAR(rt->rt_ifp);
wifi = (!cell && IFNET_IS_WIFI(rt->rt_ifp));
+ wired = (!wifi && IFNET_IS_WIRED(rt->rt_ifp));
}
/*
flags = tcp_outflags[tp->t_state];
/*
- * Send any SACK-generated retransmissions. If we're explicitly trying
- * to send out new data (when sendalot is 1), bypass this function.
- * If we retransmit in fast recovery mode, decrement snd_cwnd, since
- * we're replacing a (future) new transmission with a retransmission
- * now, and we previously incremented snd_cwnd in tcp_input().
+ * Send any SACK-generated retransmissions. If we're explicitly
+ * trying to send out new data (when sendalot is 1), bypass this
+ * function. If we retransmit in fast recovery mode, decrement
+ * snd_cwnd, since we're replacing a (future) new transmission
+ * with a retransmission now, and we previously incremented
+ * snd_cwnd in tcp_input().
*/
/*
* Still in sack recovery , reset rxmit flag to zero.
len = ((int32_t)min(cwin, p->end - p->rxmit));
}
if (len > 0) {
- off = p->rxmit - tp->snd_una; /* update off only if we really transmit SACK data */
+ off = p->rxmit - tp->snd_una;
sack_rxmit = 1;
sendalot = 1;
tcpstat.tcps_sack_rexmits++;
tcpstat.tcps_sack_rexmit_bytes +=
min(len, tp->t_maxseg);
- if (nstat_collect) {
- nstat_route_tx(inp->inp_route.ro_rt, 1,
- min(len, tp->t_maxseg),
- NSTAT_TX_FLAG_RETRANSMIT);
- INP_ADD_STAT(inp, cell, wifi, txpackets, 1);
- INP_ADD_STAT(inp, cell, wifi, txbytes,
- min(len, tp->t_maxseg));
- tp->t_stat.txretransmitbytes += min(len, tp->t_maxseg);
- }
} else {
len = 0;
}
* and timer expired, we will send what we can
* and go to transmit state.
*/
- if (tp->t_force) {
+ if (tp->t_flagsext & TF_FORCE) {
if (sendwin == 0) {
/*
* If we still have some data to send, then
* in which case len is already set.
*/
if (sack_rxmit == 0) {
- if (sack_bytes_rxmt == 0)
+ if (sack_bytes_rxmt == 0) {
len = min(so->so_snd.sb_cc, sendwin) - off;
- else {
+ } else {
int32_t cwin;
+ cwin = tp->snd_cwnd -
+ (tp->snd_nxt - tp->sack_newdata) -
+ sack_bytes_rxmt;
+ if (cwin < 0)
+ cwin = 0;
/*
* We are inside of a SACK recovery episode and are
* sending new data, having retransmitted all the
* of len is bungled by the optimizer.
*/
if (len > 0) {
- cwin = tp->snd_cwnd -
- (tp->snd_nxt - tp->sack_newdata) -
- sack_bytes_rxmt;
- if (cwin < 0)
- cwin = 0;
len = imin(len, cwin);
- }
- else
+ } else {
len = 0;
+ }
+ /*
+ * At this point SACK recovery can not send any
+ * data from scoreboard or any new data. Check
+ * if we can do a rescue retransmit towards the
+ * tail end of recovery window.
+ */
+ if (len == 0 && cwin > 0 &&
+ SEQ_LT(tp->snd_fack, tp->snd_recover) &&
+ !(tp->t_flagsext & TF_RESCUE_RXT)) {
+ len = min((tp->snd_recover - tp->snd_fack),
+ tp->t_maxseg);
+ len = imin(len, cwin);
+ old_snd_nxt = tp->snd_nxt;
+ sack_rescue_rxt = TRUE;
+ tp->snd_nxt = tp->snd_recover - len;
+ /*
+ * If FIN has been sent, snd_max
+ * must have been advanced to cover it.
+ */
+ if ((tp->t_flags & TF_SENTFIN) &&
+ tp->snd_max == tp->snd_recover)
+ tp->snd_nxt--;
+
+ off = tp->snd_nxt - tp->snd_una;
+ sendalot = 0;
+ tp->t_flagsext |= TF_RESCUE_RXT;
+ }
}
}
+#if MPTCP
+ if ((tp->t_mpflags & TMPF_FASTJOIN_SEND) &&
+ (tp->t_state == TCPS_SYN_SENT) &&
+ (!(tp->t_flags & TF_CLOSING)) &&
+ (so->so_snd.sb_cc != 0) &&
+ (tp->t_rxtshift == 0)) {
+ flags &= ~TH_SYN;
+ flags |= TH_ACK;
+ off = 0;
+ len = min(so->so_snd.sb_cc, tp->t_maxseg);
+ early_data_sent = TRUE;
+ } else if (early_data_sent) {
+ /* for now, we allow only one data segment to be sent */
+ return (0);
+ }
+#endif /* MPTCP */
/*
* Lop off SYN bit if it has already been sent. However, if this
* is SYN-SENT state and if segment contains data and if we don't
* know that foreign host supports TAO, suppress sending segment.
*/
if ((flags & TH_SYN) && SEQ_GT(tp->snd_nxt, tp->snd_una)) {
- if (tp->t_state != TCPS_SYN_RECEIVED)
+ if (tp->t_state != TCPS_SYN_RECEIVED || tfo_enabled(tp))
flags &= ~TH_SYN;
off--, len++;
if (len > 0 && tp->t_state == TCPS_SYN_SENT) {
}
+
/*
* tcp was closed while we were in ip,
* resume close
* Be careful not to send data and/or FIN on SYN segments.
* This measure is needed to prevent interoperability problems
* with not fully conformant TCP implementations.
+ *
+ * In case of TFO, we handle the setting of the len in
+ * tcp_tfo_check. In case TFO is not enabled, never ever send
+ * SYN+data.
*/
- if ((flags & TH_SYN) && (tp->t_flags & TF_NOOPT)) {
+ if ((flags & TH_SYN) && !tfo_enabled(tp)) {
len = 0;
flags &= ~TH_FIN;
}
- /* The check here used to be (len < 0). Some times len is zero when
- * the congestion window is closed and we need to check if persist timer
- * has to be set in that case. But don't set persist until connection
- * is established.
+ if ((flags & TH_SYN) && tp->t_state <= TCPS_SYN_SENT && tfo_enabled(tp))
+ len = tcp_tfo_check(tp, len);
+
+ /*
+ * The check here used to be (len < 0). Some times len is zero
+ * when the congestion window is closed and we need to check
+ * if persist timer has to be set in that case. But don't set
+ * persist until connection is established.
*/
if (len <= 0 && !(flags & TH_SYN)) {
/*
len = 0;
if (sendwin == 0) {
tp->t_timer[TCPT_REXMT] = 0;
+ tp->t_timer[TCPT_PTO] = 0;
tp->t_rxtshift = 0;
tp->t_rxtstart = 0;
tp->snd_nxt = tp->snd_una;
+ off = 0;
if (tp->t_timer[TCPT_PERSIST] == 0)
tcp_setpersist(tp);
}
}
- /* Automatic sizing of send socket buffer. Increase the send socket buffer
- * size if all of the following criteria are met
+ /*
+ * Automatic sizing of send socket buffer. Increase the send
+ * socket buffer size if all of the following criteria are met
* 1. the receiver has enough buffer space for this data
* 2. send buffer is filled to 7/8th with data (so we actually
* have data to make use of it);
(so->so_snd.sb_flags & (SB_AUTOSIZE | SB_TRIM)) == SB_AUTOSIZE &&
tcp_cansbgrow(&so->so_snd)) {
if ((tp->snd_wnd / 4 * 5) >= so->so_snd.sb_hiwat &&
- so->so_snd.sb_cc >= (so->so_snd.sb_hiwat / 8 * 7) &&
- sendwin >= (so->so_snd.sb_cc -
- (tp->snd_nxt - tp->snd_una))) {
+ so->so_snd.sb_cc >= (so->so_snd.sb_hiwat / 8 * 7) &&
+ sendwin >= (so->so_snd.sb_cc -
+ (tp->snd_nxt - tp->snd_una))) {
/* Also increase the send buffer only if the
* round-trip time is not increasing because we do
- * not want to contribute to latency by filling buffers.
+ * not want to contribute to latency by filling
+ * buffers.
* We also do not want to hold onto application's
- * old data for too long. Interactive applications would
- * rather discard old data.
+ * old data for too long. Interactive applications
+ * would rather discard old data.
*/
- if (tp->t_rttcur <=
- (basertt + 25)) {
- if (sbreserve(&so->so_snd,
- min(so->so_snd.sb_hiwat + tcp_autosndbuf_inc,
+ if (tp->t_rttcur <= (basertt + 25)) {
+ if (sbreserve(&so->so_snd,
+ min(so->so_snd.sb_hiwat + tcp_autosndbuf_inc,
tcp_autosndbuf_max)) == 1) {
so->so_snd.sb_idealsize = so->so_snd.sb_hiwat;
}
} else {
- so->so_snd.sb_idealsize =
+ so->so_snd.sb_idealsize =
max(tcp_sendspace, so->so_snd.sb_hiwat -
(2 * tcp_autosndbuf_inc));
so->so_snd.sb_flags |= SB_TRIM;
if (ipsec_bypass == 0)
ipsec_optlen = ipsec_hdrsiz_tcp(tp);
#endif
-
if (len > tp->t_maxseg) {
if ((tp->t_flags & TF_TSO) && tcp_do_tso && hwcksum_tx &&
- ip_use_randomid && kipf_count == 0 && dlil_filter_disable_tso_count == 0 &&
- tp->rcv_numsacks == 0 && sack_rxmit == 0 && sack_bytes_rxmt == 0 &&
+ ip_use_randomid && kipf_count == 0 &&
+ dlil_filter_disable_tso_count == 0 &&
+ tp->rcv_numsacks == 0 && sack_rxmit == 0 &&
+ sack_bytes_rxmt == 0 &&
inp->inp_options == NULL &&
inp->in6p_options == NULL
#if IPSEC
tso = 0;
}
}
+
+ /* Send one segment or less as a tail loss probe */
+ if (tp->t_flagsext & TF_SENT_TLPROBE) {
+ len = min(len, tp->t_maxseg);
+ sendalot = 0;
+ tso = 0;
+ }
+
#if MPTCP
- if (so->so_flags & SOF_MP_SUBFLOW) {
+ if ((so->so_flags & SOF_MP_SUBFLOW) &&
+ !(tp->t_mpflags & TMPF_TCP_FALLBACK)) {
int newlen = len;
- if ((tp->t_mpflags & TMPF_SND_MPPRIO) ||
+ if ((tp->t_state >= TCPS_ESTABLISHED) &&
+ ((tp->t_mpflags & TMPF_SND_MPPRIO) ||
(tp->t_mpflags & TMPF_SND_REM_ADDR) ||
- (tp->t_mpflags & TMPF_SND_MPFAIL)) {
+ (tp->t_mpflags & TMPF_SND_MPFAIL) ||
+ (tp->t_mpflags & TMPF_MPCAP_RETRANSMIT))) {
if (len > 0) {
len = 0;
}
sendalot = 1;
- mptcp_acknow = 1;
+ mptcp_acknow = TRUE;
} else {
- mptcp_acknow = 0;
+ mptcp_acknow = FALSE;
}
/*
* The contiguous bytes in the subflow socket buffer can be
}
}
#endif /* MPTCP */
- if (sack_rxmit) {
- if (SEQ_LT(p->rxmit + len, tp->snd_una + so->so_snd.sb_cc))
- flags &= ~TH_FIN;
- } else {
- if (SEQ_LT(tp->snd_nxt + len, tp->snd_una + so->so_snd.sb_cc))
- flags &= ~TH_FIN;
- }
-
- recwin = tcp_sbspace(tp);
/*
* If the socket is capable of doing unordered send,
}
}
+ if (sack_rxmit) {
+ if (SEQ_LT(p->rxmit + len, tp->snd_una + so->so_snd.sb_cc))
+ flags &= ~TH_FIN;
+ } else {
+ if (SEQ_LT(tp->snd_nxt + len, tp->snd_una + so->so_snd.sb_cc))
+ flags &= ~TH_FIN;
+ }
+
+ recwin = tcp_sbspace(tp);
+
/*
* Sender silly window avoidance. We transmit under the following
* conditions when len is non-zero:
* data (receiver may be limited the window size)
*/
if (len) {
- if (tp->t_force)
+ if (tp->t_flagsext & TF_FORCE)
goto send;
if (SEQ_LT(tp->snd_nxt, tp->snd_max))
goto send;
oldwin = tp->rcv_adv - tp->rcv_nxt;
if (adv >= (int32_t) (2 * tp->t_maxseg)) {
- /* Update only if the resulting scaled value of the window changed, or
- * if there is a change in the sequence since the last ack.
- * This avoids what appears as dupe ACKS (see rdar://5640997)
+ /*
+ * Update only if the resulting scaled value of
+ * the window changed, or if there is a change in
+ * the sequence since the last ack. This avoids
+ * what appears as dupe ACKS (see rdar://5640997)
*
- * If streaming is detected avoid sending too many window updates.
- * We will depend on the delack timer to send a window update
- * when needed.
+ * If streaming is detected avoid sending too many
+ * window updates. We will depend on the delack
+ * timer to send a window update when needed.
*/
if (!(tp->t_flags & TF_STRETCHACK) &&
(tp->last_ack_sent != tp->rcv_nxt ||
goto send;
}
- /* Make sure that the delayed ack timer is set if we
- * delayed sending a window update because of streaming
- * detection.
+ /*
+ * Make sure that the delayed ack timer is set if
+ * we delayed sending a window update because of
+ * streaming detection.
*/
if ((tp->t_flags & TF_STRETCHACK) &&
!(tp->t_flags & TF_DELACK)) {
}
/*
- * Send if we owe the peer an ACK, RST, SYN, or urgent data. ACKNOW
+ * Send if we owe the peer an ACK, RST, SYN, or urgent data. ACKNOW
* is also a catch-all for the retransmit timer timeout case.
*/
if (tp->t_flags & TF_ACKNOW)
* If our state indicates that FIN should be sent
* and we have not yet done so, then we need to send.
*/
- if (flags & TH_FIN &&
- ((tp->t_flags & TF_SENTFIN) == 0 || tp->snd_nxt == tp->snd_una))
+ if ((flags & TH_FIN) &&
+ (!(tp->t_flags & TF_SENTFIN) || tp->snd_nxt == tp->snd_una))
goto send;
/*
* In SACK, it is possible for tcp_output to fail to send a segment
SEQ_GT(tp->snd_max, tp->snd_una) &&
tp->t_timer[TCPT_REXMT] == 0 &&
tp->t_timer[TCPT_PERSIST] == 0) {
- tp->t_timer[TCPT_REXMT] = OFFSET_FROM_START(tp, tp->t_rxtcur);
+ tp->t_timer[TCPT_REXMT] = OFFSET_FROM_START(tp,
+ tp->t_rxtcur);
goto just_return;
}
/*
packchain_sent++;
TCP_PKTLIST_CLEAR(tp);
- error = tcp_ip_output(so, tp, packetlist, packchain_listadd,
+ error = tcp_ip_output(so, tp, packetlist,
+ packchain_listadd,
tp_inp_options, (so_options & SO_DONTROUTE),
(sack_rxmit | (sack_bytes_rxmt != 0)), recwin,
#if INET6
return (0);
send:
- /*
+ /*
* Set TF_MAXSEGSNT flag if the segment size is greater than
* the max segment size.
*/
}
#endif /* MPTCP */
}
- }
-
- /*
- RFC 3168 states that:
- - If you ever sent an ECN-setup SYN/SYN-ACK you must be prepared
- to handle the TCP ECE flag, even if you also later send a
- non-ECN-setup SYN/SYN-ACK.
- - If you ever send a non-ECN-setup SYN/SYN-ACK, you must not set
- the ip ECT flag.
-
- It is not clear how the ECE flag would ever be set if you never
- set the IP ECT flag on outbound packets. All the same, we use
- the TE_SETUPSENT to indicate that we have committed to handling
- the TCP ECE flag correctly. We use the TE_SENDIPECT to indicate
- whether or not we should set the IP ECT flag on outbound packets.
- */
- /*
- * For a SYN-ACK, send an ECN setup SYN-ACK
- */
- if (tcp_ecn_inbound && (flags & (TH_SYN | TH_ACK)) == (TH_SYN | TH_ACK)) {
- if ((tp->ecn_flags & TE_SETUPRECEIVED) != 0) {
- if ((tp->ecn_flags & TE_SETUPSENT) == 0) {
- /* Setting TH_ECE makes this an ECN-setup SYN-ACK */
- flags |= TH_ECE;
-
- /*
- * Record that we sent the ECN-setup and default to
- * setting IP ECT.
- */
- tp->ecn_flags |= (TE_SETUPSENT | TE_SENDIPECT);
- }
- else {
- /*
- * We sent an ECN-setup SYN-ACK but it was dropped.
- * Fallback to non-ECN-setup SYN-ACK and clear flag
- * that to indicate we should not send data with IP ECT set.
- *
- * Pretend we didn't receive an ECN-setup SYN.
- */
- tp->ecn_flags &= ~TE_SETUPRECEIVED;
- }
- }
- }
- else if (tcp_ecn_outbound && (flags & (TH_SYN | TH_ACK)) == TH_SYN) {
- if ((tp->ecn_flags & TE_SETUPSENT) == 0) {
- /* Setting TH_ECE and TH_CWR makes this an ECN-setup SYN */
- flags |= (TH_ECE | TH_CWR);
-
- /*
- * Record that we sent the ECN-setup and default to
- * setting IP ECT.
- */
- tp->ecn_flags |= (TE_SETUPSENT | TE_SENDIPECT);
- }
- else {
- /*
- * We sent an ECN-setup SYN but it was dropped.
- * Fall back to no ECN and clear flag indicating
- * we should send data with IP ECT set.
- */
- tp->ecn_flags &= ~TE_SENDIPECT;
- }
- }
-
- /*
- * Check if we should set the TCP CWR flag.
- * CWR flag is sent when we reduced the congestion window because
- * we received a TCP ECE or we performed a fast retransmit. We
- * never set the CWR flag on retransmitted packets. We only set
- * the CWR flag on data packets. Pure acks don't have this set.
- */
- if ((tp->ecn_flags & TE_SENDCWR) != 0 && len != 0 &&
- !SEQ_LT(tp->snd_nxt, tp->snd_max) && !sack_rxmit) {
- flags |= TH_CWR;
- tp->ecn_flags &= ~TE_SENDCWR;
- }
-
- /*
- * Check if we should set the TCP ECE flag.
- */
- if ((tp->ecn_flags & TE_SENDECE) != 0 && len == 0) {
- flags |= TH_ECE;
}
- /*
+ /*
* Send a timestamp and echo-reply if this is a SYN and our side
* wants to use timestamps (TF_REQ_TSTMP is set) or both our side
* and our peer have sent timestamps in our SYN's.
* still advance the subflow level ACK and therefore make it
* hard for the remote end to recover in low cwnd situations.
*/
- if (len != 0)
+ if (len != 0) {
tp->t_mpflags |= (TMPF_SEND_DSN |
TMPF_MPTCP_ACKNOW);
- else
+ } else {
tp->t_mpflags |= TMPF_MPTCP_ACKNOW;
+ }
optlen = mptcp_setup_opts(tp, off, &opt[0], optlen, flags,
- len, &dlenp, &finp, &dss_val, &sseqp);
+ len, &dlenp, &finp, &dss_val, &sseqp, &mptcp_acknow);
tp->t_mpflags &= ~TMPF_SEND_DSN;
}
#endif /* MPTCP */
+ if (tfo_enabled(tp) && !(tp->t_flags & TF_NOOPT) &&
+ (flags & (TH_SYN | TH_ACK)) == TH_SYN)
+ optlen += tcp_tfo_write_cookie(tp, optlen, &len, opt);
+
+ if (tfo_enabled(tp) &&
+ (flags & (TH_SYN | TH_ACK)) == (TH_SYN | TH_ACK) &&
+ (tp->t_tfo_flags & TFO_F_OFFER_COOKIE))
+ optlen += tcp_tfo_write_cookie_rep(tp, optlen, opt);
+
if (SACK_ENABLED(tp) && ((tp->t_flags & TF_NOOPT) == 0)) {
/*
* Send SACKs if necessary. This should be the last
* 10 bytes for SACK options 40 - (12 + 18).
*/
if (TCPS_HAVEESTABLISHED(tp->t_state) &&
- (tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0 &&
+ (tp->t_flags & TF_SACK_PERMIT) &&
+ (tp->rcv_numsacks > 0 || TCP_SEND_DSACK_OPT(tp)) &&
MAX_TCPOPTLEN - optlen - 2 >= TCPOLEN_SACK) {
int nsack, padlen;
u_char *bp = (u_char *)opt + optlen;
u_int32_t *lp;
nsack = (MAX_TCPOPTLEN - optlen - 2) / TCPOLEN_SACK;
- nsack = min(nsack, tp->rcv_numsacks);
+ nsack = min(nsack, (tp->rcv_numsacks +
+ (TCP_SEND_DSACK_OPT(tp) ? 1 : 0)));
sackoptlen = (2 + nsack * TCPOLEN_SACK);
/*
*bp++ = TCPOPT_SACK;
*bp++ = sackoptlen;
lp = (u_int32_t *)(void *)bp;
+
+ /*
+ * First block of SACK option should represent
+ * DSACK. Prefer to send SACK information if there
+ * is space for only one SACK block. This will
+ * allow for faster recovery.
+ */
+ if (TCP_SEND_DSACK_OPT(tp) && nsack > 0 &&
+ (tp->rcv_numsacks == 0 || nsack > 1)) {
+ *lp++ = htonl(tp->t_dsack_lseq);
+ *lp++ = htonl(tp->t_dsack_rseq);
+ tcpstat.tcps_dsack_sent++;
+ tp->t_dsack_sent++;
+ nsack--;
+ }
+ VERIFY(nsack == 0 || tp->rcv_numsacks >= nsack);
for (i = 0; i < nsack; i++) {
struct sackblk sack = tp->sackblks[i];
*lp++ = htonl(sack.start);
}
}
+ /*
+ * RFC 3168 states that:
+ * - If you ever sent an ECN-setup SYN/SYN-ACK you must be prepared
+ * to handle the TCP ECE flag, even if you also later send a
+ * non-ECN-setup SYN/SYN-ACK.
+ * - If you ever send a non-ECN-setup SYN/SYN-ACK, you must not set
+ * the ip ECT flag.
+ *
+ * It is not clear how the ECE flag would ever be set if you never
+ * set the IP ECT flag on outbound packets. All the same, we use
+ * the TE_SETUPSENT to indicate that we have committed to handling
+ * the TCP ECE flag correctly. We use the TE_SENDIPECT to indicate
+ * whether or not we should set the IP ECT flag on outbound packet
+ *
+ * For a SYN-ACK, send an ECN setup SYN-ACK
+ */
+ if ((flags & (TH_SYN | TH_ACK)) == (TH_SYN | TH_ACK) &&
+ (tp->ecn_flags & TE_ENABLE_ECN)) {
+ if (tp->ecn_flags & TE_SETUPRECEIVED) {
+ if (tcp_send_ecn_flags_on_syn(tp, so)) {
+ /*
+ * Setting TH_ECE makes this an ECN-setup
+ * SYN-ACK
+ */
+ flags |= TH_ECE;
+
+ /*
+ * Record that we sent the ECN-setup and
+ * default to setting IP ECT.
+ */
+ tp->ecn_flags |= (TE_SETUPSENT|TE_SENDIPECT);
+ tcpstat.tcps_ecn_server_setup++;
+ tcpstat.tcps_ecn_server_success++;
+ } else {
+ /*
+ * We sent an ECN-setup SYN-ACK but it was
+ * dropped. Fallback to non-ECN-setup
+ * SYN-ACK and clear flag to indicate that
+ * we should not send data with IP ECT set
+ *
+ * Pretend we didn't receive an
+ * ECN-setup SYN.
+ *
+ * We already incremented the counter
+ * assuming that the ECN setup will
+ * succeed. Decrementing here
+ * tcps_ecn_server_success to correct it.
+ */
+ if (tp->ecn_flags & TE_SETUPSENT) {
+ tcpstat.tcps_ecn_lost_synack++;
+ tcpstat.tcps_ecn_server_success--;
+ tp->ecn_flags |= TE_LOST_SYNACK;
+ }
+
+ tp->ecn_flags &=
+ ~(TE_SETUPRECEIVED | TE_SENDIPECT |
+ TE_SENDCWR);
+ }
+ }
+ } else if ((flags & (TH_SYN | TH_ACK)) == TH_SYN &&
+ (tp->ecn_flags & TE_ENABLE_ECN)) {
+ if (tcp_send_ecn_flags_on_syn(tp, so)) {
+ /*
+ * Setting TH_ECE and TH_CWR makes this an
+ * ECN-setup SYN
+ */
+ flags |= (TH_ECE | TH_CWR);
+ tcpstat.tcps_ecn_client_setup++;
+ tp->ecn_flags |= TE_CLIENT_SETUP;
+
+ /*
+ * Record that we sent the ECN-setup and default to
+ * setting IP ECT.
+ */
+ tp->ecn_flags |= (TE_SETUPSENT | TE_SENDIPECT);
+ } else {
+ /*
+ * We sent an ECN-setup SYN but it was dropped.
+ * Fall back to non-ECN and clear flag indicating
+ * we should send data with IP ECT set.
+ */
+ if (tp->ecn_flags & TE_SETUPSENT) {
+ tcpstat.tcps_ecn_lost_syn++;
+ tp->ecn_flags |= TE_LOST_SYN;
+ }
+ tp->ecn_flags &= ~TE_SENDIPECT;
+ }
+ }
+
+ /*
+ * Check if we should set the TCP CWR flag.
+ * CWR flag is sent when we reduced the congestion window because
+ * we received a TCP ECE or we performed a fast retransmit. We
+ * never set the CWR flag on retransmitted packets. We only set
+ * the CWR flag on data packets. Pure acks don't have this set.
+ */
+ if ((tp->ecn_flags & TE_SENDCWR) != 0 && len != 0 &&
+ !SEQ_LT(tp->snd_nxt, tp->snd_max) && !sack_rxmit) {
+ flags |= TH_CWR;
+ tp->ecn_flags &= ~TE_SENDCWR;
+ }
+
+ /*
+ * Check if we should set the TCP ECE flag.
+ */
+ if ((tp->ecn_flags & TE_SENDECE) != 0 && len == 0) {
+ flags |= TH_ECE;
+ tcpstat.tcps_ecn_sent_ece++;
+ }
+
+
hdrlen += optlen;
+ /* Reset DSACK sequence numbers */
+ tp->t_dsack_lseq = 0;
+ tp->t_dsack_rseq = 0;
+
#if INET6
if (isipv6)
ipoptlen = ip6_optlen(inp);
if (tp_inp_options) {
ipoptlen = tp_inp_options->m_len -
offsetof(struct ipoption, ipopt_list);
- } else
+ } else {
ipoptlen = 0;
+ }
}
#if IPSEC
ipoptlen += ipsec_optlen;
*/
if (len + optlen + ipoptlen > tp->t_maxopd) {
/*
- * If there is still more to send, don't close the connection.
+ * If there is still more to send,
+ * don't close the connection.
*/
flags &= ~TH_FIN;
if (tso) {
int32_t tso_maxlen;
- tso_maxlen = tp->tso_max_segment_size ? tp->tso_max_segment_size : TCP_MAXWIN;
+ tso_maxlen = tp->tso_max_segment_size ?
+ tp->tso_max_segment_size : TCP_MAXWIN;
if (len > tso_maxlen - hdrlen - optlen) {
len = tso_maxlen - hdrlen - optlen;
len = len - (len % (tp->t_maxopd - optlen));
sendalot = 1;
- } else if (tp->t_flags & TF_NEEDFIN)
+ } else if (tp->t_flags & TF_NEEDFIN) {
sendalot = 1;
+ }
} else {
len = tp->t_maxopd - optlen - ipoptlen;
sendalot = 1;
(tp->t_flagsext & TF_BWMEAS_INPROGRESS) == 0 &&
(so->so_snd.sb_cc - (tp->snd_max - tp->snd_una)) >=
tp->t_bwmeas->bw_minsize) {
- tp->t_bwmeas->bw_size = min((so->so_snd.sb_cc - (tp->snd_max - tp->snd_una)),
+ tp->t_bwmeas->bw_size = min(
+ (so->so_snd.sb_cc - (tp->snd_max - tp->snd_una)),
tp->t_bwmeas->bw_maxsize);
tp->t_flagsext |= TF_BWMEAS_INPROGRESS;
tp->t_bwmeas->bw_start = tp->snd_max;
* the template for sends on this connection.
*/
if (len) {
- if (tp->t_force && len == 1)
+ tp->t_pmtud_lastseg_size = len + optlen + ipoptlen;
+ if ((tp->t_flagsext & TF_FORCE) && len == 1)
tcpstat.tcps_sndprobe++;
else if (SEQ_LT(tp->snd_nxt, tp->snd_max) || sack_rxmit) {
tcpstat.tcps_sndrexmitpack++;
if (nstat_collect) {
nstat_route_tx(inp->inp_route.ro_rt, 1,
len, NSTAT_TX_FLAG_RETRANSMIT);
- INP_ADD_STAT(inp, cell, wifi, txpackets, 1);
- INP_ADD_STAT(inp, cell, wifi, txbytes, len);
+ INP_ADD_STAT(inp, cell, wifi, wired,
+ txpackets, 1);
+ INP_ADD_STAT(inp, cell, wifi, wired,
+ txbytes, len);
tp->t_stat.txretransmitbytes += len;
+ tp->t_stat.rxmitpkts++;
}
} else {
tcpstat.tcps_sndpack++;
tcpstat.tcps_sndbyte += len;
if (nstat_collect) {
- INP_ADD_STAT(inp, cell, wifi, txpackets, 1);
- INP_ADD_STAT(inp, cell, wifi, txbytes, len);
+ INP_ADD_STAT(inp, cell, wifi, wired,
+ txpackets, 1);
+ INP_ADD_STAT(inp, cell, wifi, wired,
+ txbytes, len);
}
}
#if MPTCP
*/
copymode = M_COPYM_MOVE_HDR;
#if MPTCP
- if ((tp->t_mpflags & TMPF_MPTCP_TRUE) ||
- (tp->t_mpflags & TMPF_TCP_FALLBACK)) {
+ if (so->so_flags & SOF_MP_SUBFLOW) {
copymode = M_COPYM_NOOP_HDR;
}
#endif /* MPTCP */
if (m != NULL) {
- m->m_next = m_copym_mode(so->so_snd.sb_mb, off,
- (int) len, M_DONTWAIT, copymode);
+ m->m_next = m_copym_mode(so->so_snd.sb_mb,
+ off, (int)len, M_DONTWAIT, copymode);
if (m->m_next == NULL) {
(void) m_free(m);
error = ENOBUFS;
goto out;
}
} else {
- /*
- * determine whether the mbuf pointer and
- * offset passed back by the 'last' call to
- * m_copym_with_hdrs are still valid... if the
- * head of the socket chain has changed (due
- * to an incoming ACK for instance), or the
- * offset into the chain we just computed is
- * different from the one last returned by
- * m_copym_with_hdrs (perhaps we're re-
- * transmitting a packet sent earlier), then
- * we can't pass the mbuf pointer and offset
- * into it as valid hints for m_copym_with_hdrs
- * to use (if valid, these hints allow
- * m_copym_with_hdrs to avoid rescanning from
- * the beginning of the socket buffer mbuf list.
- *
- * Setting the mbuf pointer to NULL is
- * sufficient to disable the hint mechanism.
- */
- if (m_head != so->so_snd.sb_mb || sack_rxmit ||
- last_off != off)
- m_lastm = NULL;
- last_off = off + len;
- m_head = so->so_snd.sb_mb;
-
/*
* make sure we still have data left
* to be sent at this point
*/
- if (m_head == NULL) {
+ if (so->so_snd.sb_mb == NULL) {
error = 0; /* should we return an error? */
goto out;
}
-
+
/*
* m_copym_with_hdrs will always return the
* last mbuf pointer and the offset into it that
* whether a valid 'hint' was passed in or not.
*/
if ((m = m_copym_with_hdrs(so->so_snd.sb_mb,
- off, len, M_DONTWAIT, &m_lastm, &m_off,
+ off, len, M_DONTWAIT, NULL, NULL,
copymode)) == NULL) {
error = ENOBUFS;
goto out;
* (This will keep happy those implementations which only
* give data to the user when a buffer fills or
* a PUSH comes in.)
+ *
+ * On SYN-segments we should not add the PUSH-flag.
*/
- if (off + len == so->so_snd.sb_cc)
+ if (off + len == so->so_snd.sb_cc && !(flags & TH_SYN))
flags |= TH_PUSH;
} else {
if (tp->t_flags & TF_ACKNOW)
ip6->ip6_flow |= htonl(IPTOS_ECN_ECT0 << 20);
}
svc_flags |= PKT_SCF_IPV6;
+#if PF_ECN
+ m->m_pkthdr.pf_mtag.pftag_hdr = (void *)ip6;
+ m->m_pkthdr.pf_mtag.pftag_flags |= PF_TAG_HDR_INET6;
+#endif /* PF_ECN */
} else
#endif /* INET6 */
{
/* this picks up the pseudo header (w/o the length) */
tcp_fillheaders(tp, ip, th);
if ((tp->ecn_flags & TE_SENDIPECT) != 0 && len &&
- !SEQ_LT(tp->snd_nxt, tp->snd_max) && !sack_rxmit) {
- ip->ip_tos = IPTOS_ECN_ECT0;
+ !SEQ_LT(tp->snd_nxt, tp->snd_max) &&
+ !sack_rxmit && !(flags & TH_SYN)) {
+ ip->ip_tos |= IPTOS_ECN_ECT0;
}
+#if PF_ECN
+ m->m_pkthdr.pf_mtag.pftag_hdr = (void *)ip;
+ m->m_pkthdr.pf_mtag.pftag_flags |= PF_TAG_HDR_INET;
+#endif /* PF_ECN */
}
/*
* window for use in delaying messages about window sizes.
* If resending a FIN, be sure not to use a new sequence number.
*/
- if (flags & TH_FIN && (tp->t_flags & TF_SENTFIN) &&
+ if ((flags & TH_FIN) && (tp->t_flags & TF_SENTFIN) &&
tp->snd_nxt == tp->snd_max)
tp->snd_nxt--;
/*
* right edge of the window, so use snd_nxt in that
* case, since we know we aren't doing a retransmission.
* (retransmit and persist are mutually exclusive...)
+ *
+ * Note the state of this retransmit segment to detect spurious
+ * retransmissions.
*/
if (sack_rxmit == 0) {
- if (len || (flags & (TH_SYN|TH_FIN)) || tp->t_timer[TCPT_PERSIST])
+ if (len || (flags & (TH_SYN|TH_FIN)) ||
+ tp->t_timer[TCPT_PERSIST]) {
th->th_seq = htonl(tp->snd_nxt);
- else
+ if (SEQ_LT(tp->snd_nxt, tp->snd_max)) {
+ if (SACK_ENABLED(tp) && len > 1) {
+ tcp_rxtseg_insert(tp, tp->snd_nxt,
+ (tp->snd_nxt + len - 1));
+ }
+ if (len > 0)
+ m->m_pkthdr.pkt_flags |=
+ PKTF_TCP_REXMT;
+ }
+ } else {
th->th_seq = htonl(tp->snd_max);
+ }
} else {
th->th_seq = htonl(p->rxmit);
+ tcp_rxtseg_insert(tp, p->rxmit, (p->rxmit + len - 1));
p->rxmit += len;
tp->sackhint.sack_bytes_rexmit += len;
+ if (len > 0)
+ m->m_pkthdr.pkt_flags |= PKTF_TCP_REXMT;
}
th->th_ack = htonl(tp->rcv_nxt);
tp->last_ack_sent = tp->rcv_nxt;
-
+#if MPTCP
+ /* Initialize the ACK field to a value as 0 ack fields are dropped */
+ if (early_data_sent) {
+ th->th_ack = th->th_seq + 1;
+ }
+#endif /* MPTCP */
if (optlen) {
bcopy(opt, th + 1, optlen);
th->th_off = (sizeof (struct tcphdr) + optlen) >> 2;
* In transmit state, time the transmission and arrange for
* the retransmit. In persist state, just set snd_max.
*/
- if (tp->t_force == 0 || tp->t_timer[TCPT_PERSIST] == 0) {
+ if (!(tp->t_flagsext & TF_FORCE)
+ || tp->t_timer[TCPT_PERSIST] == 0) {
tcp_seq startseq = tp->snd_nxt;
/*
if (flags & (TH_SYN|TH_FIN)) {
if (flags & TH_SYN)
tp->snd_nxt++;
- if (flags & TH_FIN) {
+ if ((flags & TH_FIN) &&
+ !(tp->t_flags & TF_SENTFIN)) {
tp->snd_nxt++;
tp->t_flags |= TF_SENTFIN;
}
}
if (sack_rxmit)
goto timer;
- tp->snd_nxt += len;
+ if (sack_rescue_rxt == TRUE) {
+ tp->snd_nxt = old_snd_nxt;
+ sack_rescue_rxt = FALSE;
+ tcpstat.tcps_pto_in_recovery++;
+ } else {
+ tp->snd_nxt += len;
+ }
if (SEQ_GT(tp->snd_nxt, tp->snd_max)) {
tp->snd_max = tp->snd_nxt;
/*
tp->t_rtttime = tcp_now;
tp->t_rtseq = startseq;
tcpstat.tcps_segstimed++;
+
+ /* update variables related to pipe ack */
+ tp->t_pipeack_lastuna = tp->snd_una;
}
}
/*
* Set retransmit timer if not currently set,
* and not doing an ack or a keep-alive probe.
- * Initial value for retransmit timer is smoothed
- * round-trip time + 2 * round-trip time variance.
- * Initialize shift counter which is used for backoff
- * of retransmit time.
*/
timer:
if (tp->t_timer[TCPT_REXMT] == 0 &&
((sack_rxmit && tp->snd_nxt != tp->snd_max) ||
- tp->snd_nxt != tp->snd_una)) {
+ tp->snd_nxt != tp->snd_una || (flags & TH_FIN))) {
if (tp->t_timer[TCPT_PERSIST]) {
tp->t_timer[TCPT_PERSIST] = 0;
tp->t_rxtshift = 0;
tp->t_rxtstart = 0;
tp->t_persist_stop = 0;
}
- tp->t_timer[TCPT_REXMT] = OFFSET_FROM_START(tp, tp->t_rxtcur);
+ tp->t_timer[TCPT_REXMT] =
+ OFFSET_FROM_START(tp, tp->t_rxtcur);
+ }
+
+ /*
+ * Set tail loss probe timeout if new data is being
+ * transmitted. This will be supported only when
+ * SACK option is enabled on a connection.
+ *
+ * Every time new data is sent PTO will get reset.
+ */
+ if (tcp_enable_tlp && tp->t_state == TCPS_ESTABLISHED &&
+ SACK_ENABLED(tp) && !IN_FASTRECOVERY(tp)
+ && tp->snd_nxt == tp->snd_max
+ && SEQ_GT(tp->snd_nxt, tp->snd_una)
+ && tp->t_rxtshift == 0
+ && (tp->t_flagsext & (TF_SENT_TLPROBE|TF_PKTS_REORDERED)) == 0) {
+ u_int32_t pto, srtt, new_rto = 0;
+
+ /*
+ * Using SRTT alone to set PTO can cause spurious
+ * retransmissions on wireless networks where there
+ * is a lot of variance in RTT. Taking variance
+ * into account will avoid this.
+ */
+ srtt = tp->t_srtt >> TCP_RTT_SHIFT;
+ pto = ((TCP_REXMTVAL(tp)) * 3) >> 1;
+ pto = max (2 * srtt, pto);
+ if ((tp->snd_max - tp->snd_una) == tp->t_maxseg)
+ pto = max(pto,
+ (((3 * pto) >> 2) + tcp_delack * 2));
+ else
+ pto = max(10, pto);
+
+ /* if RTO is less than PTO, choose RTO instead */
+ if (tp->t_rxtcur < pto) {
+ /*
+ * Schedule PTO instead of RTO in favor of
+ * fast recovery.
+ */
+ pto = tp->t_rxtcur;
+
+ /* Reset the next RTO to be after PTO. */
+ TCPT_RANGESET(new_rto,
+ (pto + TCP_REXMTVAL(tp)),
+ max(tp->t_rttmin, tp->t_rttcur + 2),
+ TCPTV_REXMTMAX, 0);
+ tp->t_timer[TCPT_REXMT] =
+ OFFSET_FROM_START(tp, new_rto);
+ }
+ tp->t_timer[TCPT_PTO] = OFFSET_FROM_START(tp, pto);
}
} else {
/*
int xlen = len;
if (flags & TH_SYN)
++xlen;
- if (flags & TH_FIN) {
+ if ((flags & TH_FIN) &&
+ !(tp->t_flags & TF_SENTFIN)) {
++xlen;
tp->t_flags |= TF_SENTFIN;
}
if (path_mtu_discovery && (tp->t_flags & TF_PMTUD))
ip->ip_off |= IP_DF;
+#if NECP
+ {
+ necp_kernel_policy_id policy_id;
+ u_int32_t route_rule_id;
+ if (!necp_socket_is_allowed_to_send_recv(inp, &policy_id, &route_rule_id)) {
+ m_freem(m);
+ error = EHOSTUNREACH;
+ goto out;
+ }
+
+ necp_mark_packet_from_socket(m, inp, policy_id, route_rule_id);
+ }
+#endif /* NECP */
+
#if IPSEC
- if (ipsec_bypass == 0)
- ipsec_setsocket(m, so);
+ if (inp->inp_sp != NULL)
+ ipsec_setsocket(m, so);
#endif /*IPSEC*/
/*
}
if (sendalot == 0 || (tp->t_state != TCPS_ESTABLISHED) ||
- (tp->snd_cwnd <= (tp->snd_wnd / 8)) ||
- (tp->t_flags & (TH_PUSH | TF_ACKNOW)) || tp->t_force != 0 ||
- tp->t_lastchain >= tcp_packet_chaining) {
+ (tp->snd_cwnd <= (tp->snd_wnd / 8)) ||
+ (tp->t_flags & (TH_PUSH | TF_ACKNOW)) ||
+ (tp->t_flagsext & TF_FORCE) ||
+ tp->t_lastchain >= tcp_packet_chaining) {
error = 0;
-
- /*
- * Reset the stack memory of offset as the socket
- * may get unlocked
- */
- m_lastm = NULL;
while (inp->inp_sndinprog_cnt == 0 &&
tp->t_pktlist_head != NULL) {
packetlist = tp->t_pktlist_head;
#else /* INET6 */
0);
#endif /* !INET6 */
-
if (error) {
/*
* Take into account the rest of unsent
* the recent call to ip_output_list() plus the amount of
* user data in the packet list for this tcp at the moment.
*/
- if (tp->t_force == 0 || tp->t_timer[TCPT_PERSIST] == 0) {
+ if (!(tp->t_flagsext & TF_FORCE)
+ || tp->t_timer[TCPT_PERSIST] == 0) {
/*
* No need to check for TH_FIN here because
* the TF_SENTFIN flag handles that case.
!tp->t_timer[TCPT_PERSIST])
tp->t_timer[TCPT_REXMT] =
OFFSET_FROM_START(tp, tp->t_rxtcur);
-
tp->snd_cwnd = tp->t_maxseg;
tp->t_bytes_acked = 0;
-
tcp_check_timer_state(tp);
KERNEL_DEBUG(DBG_FNC_TCP_OUTPUT | DBG_FUNC_END, 0,0,0,0,0);
- DTRACE_TCP5(cc, void, NULL, struct inpcb *, inp,
- struct tcpcb *, tp, struct tcphdr *, NULL,
- int32_t, TCP_CC_OUTPUT_ERROR);
+ tcp_ccdbg_trace(tp, NULL, TCP_CC_OUTPUT_ERROR);
return (0);
}
if (error == EMSGSIZE) {
* treat EHOSTUNREACH/ENETDOWN as a soft error.
*/
if ((error == EHOSTUNREACH || error == ENETDOWN) &&
- TCPS_HAVERCVDSYN(tp->t_state) &&
- !((inp->inp_flags & INP_NO_IFT_CELLULAR) &&
- inp->inp_last_outifp != NULL &&
- IFNET_IS_CELLULAR(inp->inp_last_outifp))) {
- tp->t_softerror = error;
- tcp_check_timer_state(tp);
- KERNEL_DEBUG(DBG_FNC_TCP_OUTPUT | DBG_FUNC_END,
- 0, 0, 0, 0, 0);
- return (0);
+ TCPS_HAVERCVDSYN(tp->t_state) &&
+ !inp_restricted_send(inp, inp->inp_last_outifp)) {
+ tp->t_softerror = error;
+ error = 0;
}
tcp_check_timer_state(tp);
KERNEL_DEBUG(DBG_FNC_TCP_OUTPUT | DBG_FUNC_END, 0,0,0,0,0);
}
}
- if (inp->inp_flags & INP_NO_IFT_CELLULAR) {
+ if (INP_NO_CELLULAR(inp)) {
#if INET6
if (isipv6)
ip6oa.ip6oa_flags |= IP6OAF_NO_CELLULAR;
else
#endif /* INET6 */
ipoa.ipoa_flags |= IPOAF_NO_CELLULAR;
+ }
+ if (INP_NO_EXPENSIVE(inp)) {
+#if INET6
+ if (isipv6)
+ ip6oa.ip6oa_flags |= IP6OAF_NO_EXPENSIVE;
+ else
+#endif /* INET6 */
+ ipoa.ipoa_flags |= IPOAF_NO_EXPENSIVE;
+
+ }
+ if (INP_AWDL_UNRESTRICTED(inp)) {
+#if INET6
+ if (isipv6)
+ ip6oa.ip6oa_flags |= IP6OAF_AWDL_UNRESTRICTED;
+ else
+#endif /* INET6 */
+ ipoa.ipoa_flags |= IPOAF_AWDL_UNRESTRICTED;
+
}
#if INET6
if (isipv6)
*/
if (tcp_output_unlocked && !so->so_upcallusecount &&
(tp->t_state == TCPS_ESTABLISHED) && (sack_in_progress == 0) &&
- ((tp->t_flags & TF_FASTRECOVERY) == 0)) {
+ !IN_FASTRECOVERY(tp)) {
unlocked = TRUE;
socket_unlock(so, 0);
rc = inp_set_fc_state(inp, adv->code);
if (rc == 1)
- DTRACE_TCP5(cc, void, NULL, struct inpcb *, inp,
- struct tcpcb *, tp, struct tcphdr *, NULL,
- int32_t, ((adv->code == FADV_FLOW_CONTROLLED) ?
+ tcp_ccdbg_trace(tp, NULL,
+ ((adv->code == FADV_FLOW_CONTROLLED) ?
TCP_CC_FLOW_CONTROL : TCP_CC_SUSPEND));
}
inp->inp_last_outifp)
inp->inp_last_outifp = outif;
- if (error != 0 && ifdenied && (inp->inp_flags & INP_NO_IFT_CELLULAR))
+ if (error != 0 && ifdenied &&
+ (INP_NO_CELLULAR(inp) || INP_NO_EXPENSIVE(inp)))
soevent(inp->inp_socket,
(SO_FILT_HINT_LOCKED|SO_FILT_HINT_IFDENIED));
projects / apple / xnu.git / blobdiff