X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/0b4e3aa066abc0728aacb4bbeb86f53f9737156e..c0fea4742e91338fffdcf79f86a7c1d5e2b97eb1:/bsd/netinet/tcp_subr.c diff --git a/bsd/netinet/tcp_subr.c b/bsd/netinet/tcp_subr.c index 7cd45d421..f14ece337 100644 --- a/bsd/netinet/tcp_subr.c +++ b/bsd/netinet/tcp_subr.c @@ -52,29 +52,30 @@ * SUCH DAMAGE. * * @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95 + * $FreeBSD: src/sys/netinet/tcp_subr.c,v 1.73.2.22 2001/08/22 00:59:12 silby Exp $ */ -#if ISFB31 -#include "opt_compat.h" -#include "opt_tcpdebug.h" -#endif #include #include +#include #include #include #include #include +#if INET6 #include +#endif +#include +#include #include #include #include +#include #include +#include -#if ISFB31 -#include -#endif #include #include @@ -83,19 +84,26 @@ #include #include #include +#if INET6 +#include +#endif #include +#if INET6 +#include +#endif #include #include #if INET6 -#include #include -#include #endif #include #include #include #include #include +#if INET6 +#include +#endif #include #if TCPDEBUG #include @@ -104,45 +112,97 @@ #if IPSEC #include +#if INET6 +#include +#endif #endif /*IPSEC*/ +#include #include #define DBG_FNC_TCP_CLOSE NETDBG_CODE(DBG_NETTCP, ((5 << 8) | 2)) -#ifndef offsetof /* XXX */ -#define offsetof(type, member) ((size_t)(&((type *)0)->member)) -#endif +extern int tcp_lq_overflow; + +/* temporary: for testing */ +#if IPSEC +extern int ipsec_bypass; +extern lck_mtx_t *sadb_mutex; +#endif int tcp_mssdflt = TCP_MSS; -SYSCTL_INT(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, - CTLFLAG_RW, &tcp_mssdflt , 0, ""); +SYSCTL_INT(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, CTLFLAG_RW, + &tcp_mssdflt , 0, "Default TCP Maximum Segment Size"); -int tcp_v6mssdflt = TCP6_MSS; +#if INET6 +int tcp_v6mssdflt = TCP6_MSS; SYSCTL_INT(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt, - CTLFLAG_RW, &tcp_v6mssdflt , 0, ""); + CTLFLAG_RW, &tcp_v6mssdflt , 0, + "Default TCP Maximum Segment Size for IPv6"); +#endif -static int tcp_rttdflt = TCPTV_SRTTDFLT / PR_SLOWHZ; -SYSCTL_INT(_net_inet_tcp, TCPCTL_RTTDFLT, rttdflt, - CTLFLAG_RW, &tcp_rttdflt , 0, ""); +/* + * Minimum MSS we accept and use. This prevents DoS attacks where + * we are forced to a ridiculous low MSS like 20 and send hundreds + * of packets instead of one. The effect scales with the available + * bandwidth and quickly saturates the CPU and network interface + * with packet generation and sending. Set to zero to disable MINMSS + * checking. This setting prevents us from sending too small packets. + */ +int tcp_minmss = TCP_MINMSS; +SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_RW, + &tcp_minmss , 0, "Minmum TCP Maximum Segment Size"); + +/* + * Number of TCP segments per second we accept from remote host + * before we start to calculate average segment size. If average + * segment size drops below the minimum TCP MSS we assume a DoS + * attack and reset+drop the connection. Care has to be taken not to + * set this value too small to not kill interactive type connections + * (telnet, SSH) which send many small packets. + */ +#ifdef FIX_WORKAROUND_FOR_3894301 +__private_extern__ int tcp_minmssoverload = TCP_MINMSSOVERLOAD; +#else +__private_extern__ int tcp_minmssoverload = 0; +#endif +SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmssoverload, CTLFLAG_RW, + &tcp_minmssoverload , 0, "Number of TCP Segments per Second allowed to" + "be under the MINMSS Size"); static int tcp_do_rfc1323 = 1; -SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, - CTLFLAG_RW, &tcp_do_rfc1323 , 0, ""); +SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_RW, + &tcp_do_rfc1323 , 0, "Enable rfc1323 (high performance TCP) extensions"); static int tcp_do_rfc1644 = 0; -SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1644, rfc1644, - CTLFLAG_RW, &tcp_do_rfc1644 , 0, ""); +SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1644, rfc1644, CTLFLAG_RW, + &tcp_do_rfc1644 , 0, "Enable rfc1644 (TTCP) extensions"); + +static int tcp_tcbhashsize = 0; +SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RD, + &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable"); + +static int do_tcpdrain = 0; +SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0, + "Enable tcp_drain routine for extra help when low on mbufs"); -SYSCTL_INT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_RD, &tcbinfo.ipi_count, - 0, "Number of active PCBs"); +SYSCTL_INT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_RD, + &tcbinfo.ipi_count, 0, "Number of active PCBs"); -static void tcp_cleartaocache __P((void)); -static void tcp_notify __P((struct inpcb *, int)); -extern u_long current_active_connections; +static int icmp_may_rst = 1; +SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_RW, &icmp_may_rst, 0, + "Certain ICMP unreachable messages may abort connections in SYN_SENT"); +static int tcp_strict_rfc1948 = 0; +SYSCTL_INT(_net_inet_tcp, OID_AUTO, strict_rfc1948, CTLFLAG_RW, + &tcp_strict_rfc1948, 0, "Determines if RFC1948 is followed exactly"); +static int tcp_isn_reseed_interval = 0; +SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_RW, + &tcp_isn_reseed_interval, 0, "Seconds between reseeding of ISN secret"); +static void tcp_cleartaocache(void); +static void tcp_notify(struct inpcb *, int); /* * Target size of TCP PCB hash tables. Must be a power of two. @@ -170,6 +230,10 @@ struct inp_tp { char align[(sizeof(struct inpcb) + ALIGNM1) & ~ALIGNM1]; } inp_tp_u; struct tcpcb tcb; +#ifndef __APPLE__ + struct callout inp_tp_rexmt, inp_tp_persist, inp_tp_keep, inp_tp_2msl; + struct callout inp_tp_delack; +#endif }; #undef ALIGNMENT #undef ALIGNM1 @@ -180,6 +244,7 @@ static struct tcpcb dummy_tcb; extern struct inpcbhead time_wait_slots[]; extern int cur_tw_slot; extern u_long *delack_bitmask; +extern u_long route_generation; int get_inpcb_str_size() @@ -193,7 +258,7 @@ int get_tcp_str_size() return sizeof(struct tcpcb); } -int tcp_freeq __P((struct tcpcb *tp)); +int tcp_freeq(struct tcpcb *tp); /* @@ -202,48 +267,84 @@ int tcp_freeq __P((struct tcpcb *tp)); void tcp_init() { - int hashsize; - vm_size_t str_size; - int i; - -#ifdef TCP_COMPAT_42 - tcp_iss = 1; -#endif /* TCP_COMPAT_42 */ + int hashsize = TCBHASHSIZE; + vm_size_t str_size; + int i; + struct inpcbinfo *pcbinfo; + tcp_ccgen = 1; tcp_cleartaocache(); + + tcp_delacktime = TCPTV_DELACK; + tcp_keepinit = TCPTV_KEEP_INIT; + tcp_keepidle = TCPTV_KEEP_IDLE; + tcp_keepintvl = TCPTV_KEEPINTVL; + tcp_maxpersistidle = TCPTV_KEEP_IDLE; + tcp_msl = TCPTV_MSL; + read_random(&tcp_now, sizeof(tcp_now)); + tcp_now = tcp_now & 0x7fffffff; /* Starts tcp internal 500ms clock at a random value */ + + LIST_INIT(&tcb); tcbinfo.listhead = &tcb; - if (!(getenv_int("net.inet.tcp.tcbhashsize", &hashsize))) - hashsize = TCBHASHSIZE; + pcbinfo = &tcbinfo; +#ifndef __APPLE__ + TUNABLE_INT_FETCH("net.inet.tcp.tcbhashsize", &hashsize); +#endif if (!powerof2(hashsize)) { printf("WARNING: TCB hash size not a power of 2\n"); hashsize = 512; /* safe default */ } + tcp_tcbhashsize = hashsize; tcbinfo.hashsize = hashsize; tcbinfo.hashbase = hashinit(hashsize, M_PCB, &tcbinfo.hashmask); tcbinfo.porthashbase = hashinit(hashsize, M_PCB, &tcbinfo.porthashmask); -#if ISFB31 - tcbinfo.ipi_zone = (void *) zinit("tcpcb", sizeof(struct inp_tp), maxsockets, - ZONE_INTERRUPT, 0); -#else +#ifdef __APPLE__ str_size = (vm_size_t) sizeof(struct inp_tp); - tcbinfo.ipi_zone = (void *) zinit(str_size, 120000*str_size, 8192, "inpcb_zone"); + tcbinfo.ipi_zone = (void *) zinit(str_size, 120000*str_size, 8192, "tcpcb"); +#else + tcbinfo.ipi_zone = zinit("tcpcb", sizeof(struct inp_tp), maxsockets, + ZONE_INTERRUPT, 0); +#endif + + tcp_reass_maxseg = nmbclusters / 16; +#ifndef __APPLE__ + TUNABLE_INT_FETCH("net.inet.tcp.reass.maxsegments", + &tcp_reass_maxseg); #endif + #if INET6 -#define TCP_LGHDR (sizeof(struct tcpip6hdr)) +#define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr)) #else /* INET6 */ -#define TCP_LGHDR (sizeof(struct tcpiphdr)) +#define TCP_MINPROTOHDR (sizeof(struct tcpiphdr)) #endif /* INET6 */ - if (max_protohdr < TCP_LGHDR) - max_protohdr = TCP_LGHDR; - if ((max_linkhdr + TCP_LGHDR) > MHLEN) + if (max_protohdr < TCP_MINPROTOHDR) + max_protohdr = TCP_MINPROTOHDR; + if (max_linkhdr + TCP_MINPROTOHDR > MHLEN) panic("tcp_init"); - - tcbinfo.last_pcb = 0; +#undef TCP_MINPROTOHDR dummy_tcb.t_state = TCP_NSTATES; dummy_tcb.t_flags = 0; tcbinfo.dummy_cb = (caddr_t) &dummy_tcb; + + /* + * allocate lock group attribute and group for tcp pcb mutexes + */ + pcbinfo->mtx_grp_attr = lck_grp_attr_alloc_init(); + pcbinfo->mtx_grp = lck_grp_alloc_init("tcppcb", pcbinfo->mtx_grp_attr); + + /* + * allocate the lock attribute for tcp pcb mutexes + */ + pcbinfo->mtx_attr = lck_attr_alloc_init(); + + if ((pcbinfo->mtx = lck_rw_alloc_init(pcbinfo->mtx_grp, pcbinfo->mtx_attr)) == NULL) { + printf("tcp_init: mutex not alloced!\n"); + return; /* pretty much dead if this fails... */ + } + + in_pcb_nat_init(&tcbinfo, AF_INET, IPPROTO_TCP, SOCK_STREAM); delack_bitmask = _MALLOC((4 * hashsize)/32, M_PCB, M_WAITOK); @@ -256,61 +357,85 @@ tcp_init() for (i=0; i < N_TIME_WAIT_SLOTS; i++) { LIST_INIT(&time_wait_slots[i]); } -#undef TCP_LGHDR +} + +/* + * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb. + * tcp_template used to store this data in mbufs, but we now recopy it out + * of the tcpcb each time to conserve mbufs. + */ +void +tcp_fillheaders(tp, ip_ptr, tcp_ptr) + struct tcpcb *tp; + void *ip_ptr; + void *tcp_ptr; +{ + struct inpcb *inp = tp->t_inpcb; + struct tcphdr *tcp_hdr = (struct tcphdr *)tcp_ptr; + +#if INET6 + if ((inp->inp_vflag & INP_IPV6) != 0) { + struct ip6_hdr *ip6; + + ip6 = (struct ip6_hdr *)ip_ptr; + ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) | + (inp->in6p_flowinfo & IPV6_FLOWINFO_MASK); + ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) | + (IPV6_VERSION & IPV6_VERSION_MASK); + ip6->ip6_nxt = IPPROTO_TCP; + ip6->ip6_plen = sizeof(struct tcphdr); + ip6->ip6_src = inp->in6p_laddr; + ip6->ip6_dst = inp->in6p_faddr; + tcp_hdr->th_sum = 0; + } else +#endif + { + struct ip *ip = (struct ip *) ip_ptr; + + ip->ip_vhl = IP_VHL_BORING; + ip->ip_tos = 0; + ip->ip_len = 0; + ip->ip_id = 0; + ip->ip_off = 0; + ip->ip_ttl = 0; + ip->ip_sum = 0; + ip->ip_p = IPPROTO_TCP; + ip->ip_src = inp->inp_laddr; + ip->ip_dst = inp->inp_faddr; + tcp_hdr->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, + htons(sizeof(struct tcphdr) + IPPROTO_TCP)); + } + + tcp_hdr->th_sport = inp->inp_lport; + tcp_hdr->th_dport = inp->inp_fport; + tcp_hdr->th_seq = 0; + tcp_hdr->th_ack = 0; + tcp_hdr->th_x2 = 0; + tcp_hdr->th_off = 5; + tcp_hdr->th_flags = 0; + tcp_hdr->th_win = 0; + tcp_hdr->th_urp = 0; } /* * Create template to be used to send tcp packets on a connection. - * Call after host entry created, allocates an mbuf and fills - * in a skeletal tcp/ip header, minimizing the amount of work - * necessary when the connection is used. + * Allocates an mbuf and fills in a skeletal tcp/ip header. The only + * use for this function is in keepalives, which use tcp_respond. */ struct tcptemp * -tcp_template(tp) +tcp_maketemplate(tp) struct tcpcb *tp; { - register struct inpcb *inp = tp->t_inpcb; - register struct mbuf *m; - register struct tcptemp *n; + struct mbuf *m; + struct tcptemp *n; - if ((n = tp->t_template) == 0) { - m = m_get(M_DONTWAIT, MT_HEADER); - if (m == NULL) - return (0); - m->m_len = sizeof (struct tcptemp); - n = mtod(m, struct tcptemp *); - } - bzero(n->tt_x1, sizeof(n->tt_x1)); - n->tt_pr = IPPROTO_TCP; - n->tt_len = htons(sizeof (struct tcpiphdr) - sizeof (struct ip)); - n->tt_src = inp->inp_laddr; - n->tt_dst = inp->inp_faddr; - n->tt_sport = inp->inp_lport; - n->tt_dport = inp->inp_fport; - n->tt_seq = 0; - n->tt_ack = 0; - n->tt_x2 = 0; - n->tt_off = 5; - n->tt_flags = 0; - n->tt_win = 0; - n->tt_sum = 0; - n->tt_urp = 0; - - n->tt_t.th_sum = in_pseudo(n->tt_src.s_addr, n->tt_dst.s_addr, - htons(sizeof(struct tcphdr) + IPPROTO_TCP)); + m = m_get(M_DONTWAIT, MT_HEADER); + if (m == NULL) + return (0); + m->m_len = sizeof(struct tcptemp); + n = mtod(m, struct tcptemp *); -#if INET6 - n->tt_flow = inp->inp_flow & IPV6_FLOWINFO_MASK; - if (ip6_auto_flowlabel) { - n->tt_flow &= ~IPV6_FLOWLABEL_MASK; - n->tt_flow |= (htonl(ip6_flow_seq++) & IPV6_FLOWLABEL_MASK); - } - n->tt_vfc |= IPV6_VERSION; - n->tt_pr6 = IPPROTO_TCP; - n->tt_len6 = n->tt_len; - n->tt_src6 = inp->in6p_laddr; - n->tt_dst6 = inp->in6p_faddr; -#endif /* INET6 */ + tcp_fillheaders(tp, (void *)&n->tt_ipgen, (void *)&n->tt_t); return (n); } @@ -319,10 +444,9 @@ tcp_template(tp) * the given TCP/IP header. If m == 0, then we make a copy * of the tcpiphdr at ti and send directly to the addressed host. * This is used to force keep alive messages out using the TCP - * template for a connection tp->t_template. If flags are given - * then we send a message back to the TCP which originated the - * segment ti, and discard the mbuf containing it and any other - * attached mbufs. + * template for a connection. If flags are given then we send + * a message back to the TCP which originated the * segment ti, + * and discard the mbuf containing it and any other attached mbufs. * * In any case the ack and sequence number of the transmitted * segment are as specified by the parameters. @@ -330,34 +454,40 @@ tcp_template(tp) * NOTE: If m != NULL, then ti must point to *inside* the mbuf. */ void -tcp_respond(tp, iph, th, m, ack, seq, flags, isipv6) +tcp_respond(tp, ipgen, th, m, ack, seq, flags) struct tcpcb *tp; - void *iph; + void *ipgen; register struct tcphdr *th; register struct mbuf *m; tcp_seq ack, seq; int flags; -#if INET6 - int isipv6; -#endif { register int tlen; int win = 0; struct route *ro = 0; struct route sro; - struct ip *ip = iph; - struct tcpiphdr *ti = iph; + struct ip *ip; struct tcphdr *nth; #if INET6 struct route_in6 *ro6 = 0; struct route_in6 sro6; - struct ip6_hdr *ip6 = iph; - struct tcpip6hdr *ti6 = iph; + struct ip6_hdr *ip6; + int isipv6; +#endif /* INET6 */ + int ipflags = 0; + +#if INET6 + isipv6 = IP_VHL_V(((struct ip *)ipgen)->ip_vhl) == 6; + ip6 = ipgen; #endif /* INET6 */ + ip = ipgen; if (tp) { - if (!(flags & TH_RST)) + if (!(flags & TH_RST)) { win = sbspace(&tp->t_inpcb->inp_socket->so_rcv); + if (win > (long)TCP_MAXWIN << tp->rcv_scale) + win = (long)TCP_MAXWIN << tp->rcv_scale; + } #if INET6 if (isipv6) ro6 = &tp->t_inpcb->in6p_route; @@ -369,76 +499,78 @@ tcp_respond(tp, iph, th, m, ack, seq, flags, isipv6) if (isipv6) { ro6 = &sro6; bzero(ro6, sizeof *ro6); - } else { + } else #endif /* INET6 */ - ro = &sro; - bzero(ro, sizeof *ro); -#if INET6 + { + ro = &sro; + bzero(ro, sizeof *ro); } -#endif /* INET6 */ } if (m == 0) { m = m_gethdr(M_DONTWAIT, MT_HEADER); if (m == NULL) return; -#if TCP_COMPAT_42 - tlen = 1; -#else tlen = 0; -#endif m->m_data += max_linkhdr; #if INET6 if (isipv6) { - ti6 = mtod(m, struct tcpip6hdr *); - bcopy((caddr_t)ip6, (caddr_t)&ti6->ti6_i, + bcopy((caddr_t)ip6, mtod(m, caddr_t), sizeof(struct ip6_hdr)); - ip6 = &ti6->ti6_i; - nth = &ti6->ti6_t; - } else { + ip6 = mtod(m, struct ip6_hdr *); + nth = (struct tcphdr *)(ip6 + 1); + } else #endif /* INET6 */ - ti = mtod(m, struct tcpiphdr *); - bcopy((caddr_t)ip, (caddr_t)&ti->ti_i, sizeof(struct ip)); - ip = (struct ip *)&ti->ti_i; - nth = &ti->ti_t; -#if INET6 + { + bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip)); + ip = mtod(m, struct ip *); + nth = (struct tcphdr *)(ip + 1); } -#endif /* INET6 */ bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr)); flags = TH_ACK; } else { m_freem(m->m_next); m->m_next = 0; - m->m_data = (caddr_t)ti; + m->m_data = (caddr_t)ipgen; /* m_len is set later */ tlen = 0; #define xchg(a,b,type) { type t; t=a; a=b; b=t; } #if INET6 if (isipv6) { - struct in6_addr t; - - t = ip6->ip6_dst; - ip6->ip6_dst = ip6->ip6_src; - ip6->ip6_src = t; + xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr); nth = (struct tcphdr *)(ip6 + 1); - if (th != nth) { - /* - * this is the case if an extension header - * exists between the IPv6 header and the - * TCP header. - */ - nth->th_sport = th->th_sport; - nth->th_dport = th->th_dport; - } - } else { + } else #endif /* INET6 */ - xchg(ti->ti_dst.s_addr, ti->ti_src.s_addr, n_long); - nth = th; -#if INET6 + { + xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, n_long); + nth = (struct tcphdr *)(ip + 1); + } + if (th != nth) { + /* + * this is usually a case when an extension header + * exists between the IPv6 header and the + * TCP header. + */ + nth->th_sport = th->th_sport; + nth->th_dport = th->th_dport; } -#endif /* INET6 */ xchg(nth->th_dport, nth->th_sport, n_short); #undef xchg } +#if INET6 + if (isipv6) { + ip6->ip6_plen = htons((u_short)(sizeof (struct tcphdr) + + tlen)); + tlen += sizeof (struct ip6_hdr) + sizeof (struct tcphdr); + } else +#endif + { + tlen += sizeof (struct tcpiphdr); + ip->ip_len = tlen; + ip->ip_ttl = ip_defttl; + } + m->m_len = tlen; + m->m_pkthdr.len = tlen; + m->m_pkthdr.rcvif = 0; nth->th_seq = htonl(seq); nth->th_ack = htonl(ack); nth->th_x2 = 0; @@ -449,67 +581,50 @@ tcp_respond(tp, iph, th, m, ack, seq, flags, isipv6) else nth->th_win = htons((u_short)win); nth->th_urp = 0; - tlen += sizeof (struct tcphdr); #if INET6 if (isipv6) { - m->m_len = tlen + sizeof(struct ip6_hdr); - m->m_pkthdr.len = tlen + sizeof(struct ip6_hdr); - m->m_pkthdr.rcvif = (struct ifnet *) 0; - ip6->ip6_plen = htons((u_short)tlen); - ip6->ip6_nxt = IPPROTO_TCP; + nth->th_sum = 0; + nth->th_sum = in6_cksum(m, IPPROTO_TCP, + sizeof(struct ip6_hdr), + tlen - sizeof(struct ip6_hdr)); ip6->ip6_hlim = in6_selecthlim(tp ? tp->t_inpcb : NULL, ro6 && ro6->ro_rt ? ro6->ro_rt->rt_ifp : NULL); - nth->th_sum = in6_cksum(m, IPPROTO_TCP, - sizeof(struct ip6_hdr), tlen); - ip6->ip6_flow &= ~IPV6_FLOWLABEL_MASK; - if (ip6_auto_flowlabel) { - ip6->ip6_flow |= - (htonl(ip6_flow_seq++) & IPV6_FLOWLABEL_MASK); - } - } else { + } else #endif /* INET6 */ - ti->ti_len = htons((u_short)(tlen)); - m->m_len = tlen + sizeof(struct ip); - m->m_pkthdr.len = tlen + sizeof(struct ip); - m->m_pkthdr.rcvif = (struct ifnet *) 0; - nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, - htons((u_short)(tlen + IPPROTO_TCP))); - m->m_pkthdr.csum_flags = CSUM_TCP; - m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); - - ip->ip_len = tlen + sizeof (struct ip); - ip->ip_ttl = ip_defttl; -#if INET6 + { + nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr, + htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p))); + m->m_pkthdr.csum_flags = CSUM_TCP; + m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum); } -#endif /* INET6 */ #if TCPDEBUG if (tp == NULL || (tp->t_inpcb->inp_socket->so_options & SO_DEBUG)) - tcp_trace(TA_OUTPUT, 0, tp, -#if INET6 - isipv6 ? (void *)ip6 : -#endif /* INET6 */ - ip, - nth, 0); + tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0); #endif #if IPSEC - ipsec_setsocket(m, tp ? tp->t_inpcb->inp_socket : NULL); -#endif /*IPSEC*/ + if (ipsec_bypass == 0 && ipsec_setsocket(m, tp ? tp->t_inpcb->inp_socket : NULL) != 0) { + m_freem(m); + return; + } +#endif #if INET6 if (isipv6) { - (void)ip6_output(m, NULL, ro6, 0, NULL, NULL); - if (ro6 == &sro6 && ro6->ro_rt) - RTFREE(ro6->ro_rt); - } else { + (void)ip6_output(m, NULL, ro6, ipflags, NULL, NULL, 0); + if (ro6 == &sro6 && ro6->ro_rt) { + rtfree(ro6->ro_rt); + ro6->ro_rt = NULL; + } + } else #endif /* INET6 */ - (void)ip_output(m, NULL, ro, 0, NULL); - if (ro == &sro && ro->ro_rt) { - RTFREE(ro->ro_rt); - } -#if INET6 + { + (void) ip_output_list(m, 0, NULL, ro, ipflags, NULL); + if (ro == &sro && ro->ro_rt) { + rtfree(ro->ro_rt); + ro->ro_rt = NULL; + } } -#endif /* INET6 */ } /* @@ -526,10 +641,9 @@ tcp_newtcpcb(inp) register struct tcpcb *tp; register struct socket *so = inp->inp_socket; #if INET6 - int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; + int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; #endif /* INET6 */ - if (so->cached_in_sock_layer == 0) { it = (struct inp_tp *)inp; tp = &it->tcb; @@ -538,13 +652,21 @@ tcp_newtcpcb(inp) tp = (struct tcpcb *) inp->inp_saved_ppcb; bzero((char *) tp, sizeof(struct tcpcb)); - tp->segq.lh_first = NULL; - tp->t_maxseg = tp->t_maxopd = + LIST_INIT(&tp->t_segq); + tp->t_maxseg = tp->t_maxopd = #if INET6 - isipv6 ? tcp_v6mssdflt : + isipv6 ? tcp_v6mssdflt : #endif /* INET6 */ - tcp_mssdflt; - + tcp_mssdflt; + +#ifndef __APPLE__ + /* Set up our timeouts. */ + callout_init(tp->tt_rexmt = &it->inp_tp_rexmt); + callout_init(tp->tt_persist = &it->inp_tp_persist); + callout_init(tp->tt_keep = &it->inp_tp_keep); + callout_init(tp->tt_2msl = &it->inp_tp_2msl); + callout_init(tp->tt_delack = &it->inp_tp_delack); +#endif if (tcp_do_rfc1323) tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP); @@ -562,11 +684,10 @@ tcp_newtcpcb(inp) tp->t_rxtcur = TCPTV_RTOBASE; tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT; tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT; - /* + /* * IPv4 TTL initialization is necessary for an IPv6 socket as well, * because the socket may be bound to an IPv6 wildcard address, * which may match an IPv4-mapped IPv6 address. - * XXX: is there a better approach? */ inp->inp_ip_ttl = ip_defttl; inp->inp_ppcb = (caddr_t)tp; @@ -585,6 +706,7 @@ tcp_drop(tp, errno) { struct socket *so = tp->t_inpcb->inp_socket; +#ifdef __APPLE__ switch (tp->t_state) { case TCPS_ESTABLISHED: @@ -592,10 +714,10 @@ tcp_drop(tp, errno) case TCPS_CLOSING: case TCPS_CLOSE_WAIT: case TCPS_LAST_ACK: - current_active_connections--; break; } - +#endif + if (TCPS_HAVERCVDSYN(tp->t_state)) { tp->t_state = TCPS_CLOSED; (void) tcp_output(tp); @@ -618,16 +740,37 @@ struct tcpcb * tcp_close(tp) register struct tcpcb *tp; { - register struct mbuf *q; - register struct mbuf *nq; + register struct tseg_qent *q; struct inpcb *inp = tp->t_inpcb; struct socket *so = inp->inp_socket; #if INET6 - int isipv6 = INP_CHECK_SOCKAF(so, AF_INET6); + int isipv6 = (inp->inp_vflag & INP_IPV6) != 0; #endif /* INET6 */ register struct rtentry *rt; int dosavessthresh; + if ( inp->inp_ppcb == NULL) /* tcp_close was called previously, bail */ + return; + +#ifndef __APPLE__ + /* + * Make sure that all of our timers are stopped before we + * delete the PCB. + */ + callout_stop(tp->tt_rexmt); + callout_stop(tp->tt_persist); + callout_stop(tp->tt_keep); + callout_stop(tp->tt_2msl); + callout_stop(tp->tt_delack); +#else + /* Clear the timers before we delete the PCB. */ + { + int i; + for (i = 0; i < TCPT_NTIMERS; i++) { + tp->t_timer[i] = 0; + } + } +#endif KERNEL_DEBUG(DBG_FNC_TCP_CLOSE | DBG_FUNC_START, tp,0,0,0,0); switch (tp->t_state) @@ -637,7 +780,6 @@ tcp_close(tp) case TCPS_CLOSING: case TCPS_CLOSE_WAIT: case TCPS_LAST_ACK: - current_active_connections--; break; } @@ -666,11 +808,16 @@ tcp_close(tp) goto no_valid_rt; } else -#endif /* INET6 */ - if ((rt = inp->inp_route.ro_rt) == NULL || +#endif /* INET6 */ + rt = inp->inp_route.ro_rt; + if (rt == NULL || ((struct sockaddr_in *)rt_key(rt))->sin_addr.s_addr - == INADDR_ANY) + == INADDR_ANY || rt->generation_id != route_generation) { + if (tp->t_state >= TCPS_CLOSE_WAIT) + tp->t_state = TCPS_CLOSING; + goto no_valid_rt; + } if ((rt->rt_rmx.rmx_locks & RTV_RTT) == 0) { i = tp->t_srtt * @@ -729,9 +876,14 @@ tcp_close(tp) i = 2; i *= (u_long)(tp->t_maxseg + #if INET6 - isipv6 ? sizeof (struct tcpip6hdr) : -#endif /* INET6 */ - sizeof (struct tcpiphdr)); + (isipv6 ? sizeof (struct ip6_hdr) + + sizeof (struct tcphdr) : +#endif + sizeof (struct tcpiphdr) +#if INET6 + ) +#endif + ); if (rt->rt_rmx.rmx_ssthresh) rt->rt_rmx.rmx_ssthresh = (rt->rt_rmx.rmx_ssthresh + i) / 2; @@ -740,20 +892,30 @@ tcp_close(tp) tcpstat.tcps_cachedssthresh++; } } + rt = inp->inp_route.ro_rt; + if (rt) { + /* + * mark route for deletion if no information is + * cached. + */ + if ((tp->t_flags & TF_LQ_OVERFLOW) && tcp_lq_overflow && + ((rt->rt_rmx.rmx_locks & RTV_RTT) == 0)){ + if (rt->rt_rmx.rmx_rtt == 0) + rt->rt_flags |= RTF_DELCLONE; + } + } no_valid_rt: /* free the reassembly queue, if any */ (void) tcp_freeq(tp); - if (tp->t_template) - (void) m_free(dtom(tp->t_template)); - +#ifdef __APPLE__ if (so->cached_in_sock_layer) inp->inp_saved_ppcb = (caddr_t) tp; +#endif - inp->inp_ppcb = NULL; soisdisconnected(so); #if INET6 - if (isipv6) + if (INP_CHECK_SOCKAF(so, AF_INET6)) in6_pcbdetach(inp); else #endif /* INET6 */ @@ -767,13 +929,15 @@ int tcp_freeq(tp) struct tcpcb *tp; { - register struct ipqent *qe; + + register struct tseg_qent *q; int rv = 0; - while ((qe = tp->segq.lh_first) != NULL) { - LIST_REMOVE(qe, ipqe_q); - m_freem(qe->ipqe_m); - FREE(qe, M_SONAME); + while((q = LIST_FIRST(&tp->t_segq)) != NULL) { + LIST_REMOVE(q, tqe_q); + m_freem(q->tqe_m); + FREE(q, M_TSEGQ); + tcp_reass_qsize--; rv = 1; } return (rv); @@ -782,21 +946,60 @@ tcp_freeq(tp) void tcp_drain() { +/* + * ###LD 05/19/04 locking issue, tcpdrain is disabled, deadlock situation with tcbinfo.mtx + */ + if (do_tcpdrain) + { + struct inpcb *inpb; + struct tcpcb *tcpb; + struct tseg_qent *te; + /* + * Walk the tcpbs, if existing, and flush the reassembly queue, + * if there is one... + * XXX: The "Net/3" implementation doesn't imply that the TCP + * reassembly queue should be flushed, but in a situation + * where we're really low on mbufs, this is potentially + * usefull. + */ + lck_rw_lock_exclusive(tcbinfo.mtx); + for (inpb = LIST_FIRST(tcbinfo.listhead); inpb; + inpb = LIST_NEXT(inpb, inp_list)) { + if ((tcpb = intotcpcb(inpb))) { + while ((te = LIST_FIRST(&tcpb->t_segq)) + != NULL) { + LIST_REMOVE(te, tqe_q); + m_freem(te->tqe_m); + FREE(te, M_TSEGQ); + tcp_reass_qsize--; + } + } + } + lck_rw_done(tcbinfo.mtx); + + } } /* * Notify a tcp user of an asynchronous error; * store error as soft error, but wake up user * (for now, won't do anything until can select for soft error). + * + * Do not wake up user since there currently is no mechanism for + * reporting soft errors (yet - a kqueue filter may be added). */ static void tcp_notify(inp, error) struct inpcb *inp; int error; { - register struct tcpcb *tp = (struct tcpcb *)inp->inp_ppcb; - register struct socket *so = inp->inp_socket; + struct tcpcb *tp; + + if (inp == NULL || (inp->inp_state == INPCB_STATE_DEAD)) + return; /* pcb is gone already */ + + tp = (struct tcpcb *)inp->inp_ppcb; /* * Ignore some errors if we are hooked up. @@ -811,15 +1014,16 @@ tcp_notify(inp, error) return; } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 && tp->t_softerror) - so->so_error = error; + tcp_drop(tp, error); else tp->t_softerror = error; +#if 0 wakeup((caddr_t) &so->so_timeo); sorwakeup(so); sowwakeup(so); +#endif } - static int tcp_pcblist SYSCTL_HANDLER_ARGS { @@ -832,59 +1036,78 @@ tcp_pcblist SYSCTL_HANDLER_ARGS * The process of preparing the TCB list is too time-consuming and * resource-intensive to repeat twice on every request. */ - if (req->oldptr == 0) { + lck_rw_lock_shared(tcbinfo.mtx); + if (req->oldptr == USER_ADDR_NULL) { n = tcbinfo.ipi_count; req->oldidx = 2 * (sizeof xig) + (n + n/8) * sizeof(struct xtcpcb); + lck_rw_done(tcbinfo.mtx); return 0; } - if (req->newptr != 0) + if (req->newptr != USER_ADDR_NULL) { + lck_rw_done(tcbinfo.mtx); return EPERM; + } /* * OK, now we're committed to doing something. */ - s = splnet(); gencnt = tcbinfo.ipi_gencnt; n = tcbinfo.ipi_count; - splx(s); + bzero(&xig, sizeof(xig)); xig.xig_len = sizeof xig; xig.xig_count = n; xig.xig_gen = gencnt; xig.xig_sogen = so_gencnt; error = SYSCTL_OUT(req, &xig, sizeof xig); - if (error) + if (error) { + lck_rw_done(tcbinfo.mtx); return error; + } /* * We are done if there is no pcb */ - if (n == 0) + if (n == 0) { + lck_rw_done(tcbinfo.mtx); return 0; + } inp_list = _MALLOC(n * sizeof *inp_list, M_TEMP, M_WAITOK); - if (inp_list == 0) + if (inp_list == 0) { + lck_rw_done(tcbinfo.mtx); return ENOMEM; + } - s = splnet(); - for (inp = tcbinfo.listhead->lh_first, i = 0; inp && i < n; - inp = inp->inp_list.le_next) { - if (inp->inp_gencnt <= gencnt) + for (inp = LIST_FIRST(tcbinfo.listhead), i = 0; inp && i < n; + inp = LIST_NEXT(inp, inp_list)) { +#ifdef __APPLE__ + if (inp->inp_gencnt <= gencnt && inp->inp_state != INPCB_STATE_DEAD) +#else + if (inp->inp_gencnt <= gencnt && !prison_xinpcb(req->p, inp)) +#endif inp_list[i++] = inp; } - splx(s); n = i; error = 0; for (i = 0; i < n; i++) { inp = inp_list[i]; - if (inp->inp_gencnt <= gencnt) { + if (inp->inp_gencnt <= gencnt && inp->inp_state != INPCB_STATE_DEAD) { struct xtcpcb xt; + caddr_t inp_ppcb; + + bzero(&xt, sizeof(xt)); xt.xt_len = sizeof xt; /* XXX should avoid extra copy */ - bcopy(inp, &xt.xt_inp, sizeof *inp); - bcopy(inp->inp_ppcb, &xt.xt_tp, sizeof xt.xt_tp); + inpcb_to_compat(inp, &xt.xt_inp); + inp_ppcb = inp->inp_ppcb; + if (inp_ppcb != NULL) { + bcopy(inp_ppcb, &xt.xt_tp, sizeof xt.xt_tp); + } + else + bzero((char *) &xt.xt_tp, sizeof xt.xt_tp); if (inp->inp_socket) sotoxsocket(inp->inp_socket, &xt.xt_socket); error = SYSCTL_OUT(req, &xt, sizeof xt); @@ -898,45 +1121,154 @@ tcp_pcblist SYSCTL_HANDLER_ARGS * while we were processing this request, and it * might be necessary to retry. */ - s = splnet(); + bzero(&xig, sizeof(xig)); + xig.xig_len = sizeof xig; xig.xig_gen = tcbinfo.ipi_gencnt; xig.xig_sogen = so_gencnt; xig.xig_count = tcbinfo.ipi_count; - splx(s); error = SYSCTL_OUT(req, &xig, sizeof xig); } FREE(inp_list, M_TEMP); + lck_rw_done(tcbinfo.mtx); return error; } - SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0, tcp_pcblist, "S,xtcpcb", "List of active TCP connections"); +#ifndef __APPLE__ +static int +tcp_getcred(SYSCTL_HANDLER_ARGS) +{ + struct sockaddr_in addrs[2]; + struct inpcb *inp; + int error, s; + + error = suser(req->p); + if (error) + return (error); + error = SYSCTL_IN(req, addrs, sizeof(addrs)); + if (error) + return (error); + s = splnet(); + inp = in_pcblookup_hash(&tcbinfo, addrs[1].sin_addr, addrs[1].sin_port, + addrs[0].sin_addr, addrs[0].sin_port, 0, NULL); + if (inp == NULL || inp->inp_socket == NULL) { + error = ENOENT; + goto out; + } + error = SYSCTL_OUT(req, inp->inp_socket->so_cred, sizeof(*(kauth_cred_t)0); +out: + splx(s); + return (error); +} + +SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, CTLTYPE_OPAQUE|CTLFLAG_RW, + 0, 0, tcp_getcred, "S,ucred", "Get the ucred of a TCP connection"); + +#if INET6 +static int +tcp6_getcred(SYSCTL_HANDLER_ARGS) +{ + struct sockaddr_in6 addrs[2]; + struct inpcb *inp; + int error, s, mapped = 0; + + error = suser(req->p); + if (error) + return (error); + error = SYSCTL_IN(req, addrs, sizeof(addrs)); + if (error) + return (error); + if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) { + if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr)) + mapped = 1; + else + return (EINVAL); + } + s = splnet(); + if (mapped == 1) + inp = in_pcblookup_hash(&tcbinfo, + *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12], + addrs[1].sin6_port, + *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12], + addrs[0].sin6_port, + 0, NULL); + else + inp = in6_pcblookup_hash(&tcbinfo, &addrs[1].sin6_addr, + addrs[1].sin6_port, + &addrs[0].sin6_addr, addrs[0].sin6_port, + 0, NULL); + if (inp == NULL || inp->inp_socket == NULL) { + error = ENOENT; + goto out; + } + error = SYSCTL_OUT(req, inp->inp_socket->so_cred, + sizeof(*(kauth_cred_t)0); +out: + splx(s); + return (error); +} + +SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, CTLTYPE_OPAQUE|CTLFLAG_RW, + 0, 0, + tcp6_getcred, "S,ucred", "Get the ucred of a TCP6 connection"); +#endif +#endif /* __APPLE__*/ + void tcp_ctlinput(cmd, sa, vip) int cmd; struct sockaddr *sa; void *vip; { - register struct ip *ip = vip; - register struct tcphdr *th; - void (*notify) __P((struct inpcb *, int)) = tcp_notify; + struct ip *ip = vip; + struct tcphdr *th; + struct in_addr faddr; + struct inpcb *inp; + struct tcpcb *tp; + void (*notify)(struct inpcb *, int) = tcp_notify; + tcp_seq icmp_seq; + int s; + + faddr = ((struct sockaddr_in *)sa)->sin_addr; + if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY) + return; if (cmd == PRC_QUENCH) notify = tcp_quench; + else if (icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB || + cmd == PRC_UNREACH_PORT) && ip) + notify = tcp_drop_syn_sent; else if (cmd == PRC_MSGSIZE) notify = tcp_mtudisc; - else if (!PRC_IS_REDIRECT(cmd) && - ((unsigned)cmd > PRC_NCMDS || inetctlerrmap[cmd] == 0)) + else if (PRC_IS_REDIRECT(cmd)) { + ip = 0; + notify = in_rtchange; + } else if (cmd == PRC_HOSTDEAD) + ip = 0; + else if ((unsigned)cmd > PRC_NCMDS || inetctlerrmap[cmd] == 0) return; if (ip) { th = (struct tcphdr *)((caddr_t)ip + (IP_VHL_HL(ip->ip_vhl) << 2)); - in_pcbnotify(&tcb, sa, th->th_dport, ip->ip_src, th->th_sport, - cmd, notify); + inp = in_pcblookup_hash(&tcbinfo, faddr, th->th_dport, + ip->ip_src, th->th_sport, 0, NULL); + if (inp != NULL && inp->inp_socket != NULL) { + tcp_lock(inp->inp_socket, 1, 0); + if (in_pcb_checkstate(inp, WNT_RELEASE, 1) == WNT_STOPUSING) { + tcp_unlock(inp->inp_socket, 1, 0); + return; + } + icmp_seq = htonl(th->th_seq); + tp = intotcpcb(inp); + if (SEQ_GEQ(icmp_seq, tp->snd_una) && + SEQ_LT(icmp_seq, tp->snd_max)) + (*notify)(inp, inetctlerrmap[cmd]); + tcp_unlock(inp->inp_socket, 1, 0); + } } else - in_pcbnotify(&tcb, sa, 0, zeroin_addr, 0, cmd, notify); + in_pcbnotifyall(&tcbinfo, faddr, inetctlerrmap[cmd], notify); } #if INET6 @@ -946,13 +1278,17 @@ tcp6_ctlinput(cmd, sa, d) struct sockaddr *sa; void *d; { - register struct tcphdr *thp; struct tcphdr th; - void (*notify) __P((struct inpcb *, int)) = tcp_notify; - struct sockaddr_in6 sa6; + void (*notify)(struct inpcb *, int) = tcp_notify; struct ip6_hdr *ip6; struct mbuf *m; - int off = 0 ; + struct ip6ctlparam *ip6cp = NULL; + const struct sockaddr_in6 *sa6_src = NULL; + int off; + struct tcp_portonly { + u_int16_t th_sport; + u_int16_t th_dport; + } *thp; if (sa->sa_family != AF_INET6 || sa->sa_len != sizeof(struct sockaddr_in6)) @@ -968,107 +1304,145 @@ tcp6_ctlinput(cmd, sa, d) /* if the parameter is from icmp6, decode it. */ if (d != NULL) { - struct ip6ctlparam *ip6cp = (struct ip6ctlparam *)d; + ip6cp = (struct ip6ctlparam *)d; m = ip6cp->ip6c_m; ip6 = ip6cp->ip6c_ip6; off = ip6cp->ip6c_off; + sa6_src = ip6cp->ip6c_src; } else { m = NULL; ip6 = NULL; + off = 0; /* fool gcc */ + sa6_src = &sa6_any; } - /* translate addresses into internal form */ - sa6 = *(struct sockaddr_in6 *)sa; - if (IN6_IS_ADDR_LINKLOCAL(&sa6.sin6_addr) && m && m->m_pkthdr.rcvif) - sa6.sin6_addr.s6_addr16[1] = htons(m->m_pkthdr.rcvif->if_index); - if (ip6) { /* * XXX: We assume that when IPV6 is non NULL, * M and OFF are valid. */ - struct in6_addr s; - /* translate addresses into internal form */ - memcpy(&s, &ip6->ip6_src, sizeof(s)); - if (IN6_IS_ADDR_LINKLOCAL(&s)) - s.s6_addr16[1] = htons(m->m_pkthdr.rcvif->if_index); + /* check if we can safely examine src and dst ports */ + if (m->m_pkthdr.len < off + sizeof(*thp)) + return; + bzero(&th, sizeof(th)); + m_copydata(m, off, sizeof(*thp), (caddr_t)&th); - if (m->m_len < off + sizeof(*thp)) { - /* - * this should be rare case, - * so we compromise on this copy... - */ - m_copydata(m, off, sizeof(th), (caddr_t)&th); - thp = &th; - } else - thp = (struct tcphdr *)(mtod(m, caddr_t) + off); - in6_pcbnotify(&tcb, (struct sockaddr *)&sa6, thp->th_dport, - &s, thp->th_sport, cmd, notify); + in6_pcbnotify(&tcbinfo, sa, th.th_dport, + (struct sockaddr *)ip6cp->ip6c_src, + th.th_sport, cmd, notify); } else - in6_pcbnotify(&tcb, (struct sockaddr *)&sa6, 0, &zeroin6_addr, + in6_pcbnotify(&tcbinfo, sa, 0, (struct sockaddr *)sa6_src, 0, cmd, notify); } #endif /* INET6 */ -#define TCP_RNDISS_ROUNDS 16 -#define TCP_RNDISS_OUT 7200 -#define TCP_RNDISS_MAX 30000 - -u_int8_t tcp_rndiss_sbox[128]; -u_int16_t tcp_rndiss_msb; -u_int16_t tcp_rndiss_cnt; -long tcp_rndiss_reseed; - -u_int16_t -tcp_rndiss_encrypt(val) - u_int16_t val; -{ - u_int16_t sum = 0, i; - - for (i = 0; i < TCP_RNDISS_ROUNDS; i++) { - sum += 0x79b9; - val ^= ((u_int16_t)tcp_rndiss_sbox[(val^sum) & 0x7f]) << 7; - val = ((val & 0xff) << 7) | (val >> 8); - } - - return val; -} -void -tcp_rndiss_init() -{ - struct timeval time; +/* + * Following is where TCP initial sequence number generation occurs. + * + * There are two places where we must use initial sequence numbers: + * 1. In SYN-ACK packets. + * 2. In SYN packets. + * + * The ISNs in SYN-ACK packets have no monotonicity requirement, + * and should be as unpredictable as possible to avoid the possibility + * of spoofing and/or connection hijacking. To satisfy this + * requirement, SYN-ACK ISNs are generated via the arc4random() + * function. If exact RFC 1948 compliance is requested via sysctl, + * these ISNs will be generated just like those in SYN packets. + * + * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling + * depends on this property. In addition, these ISNs should be + * unguessable so as to prevent connection hijacking. To satisfy + * the requirements of this situation, the algorithm outlined in + * RFC 1948 is used to generate sequence numbers. + * + * For more information on the theory of operation, please see + * RFC 1948. + * + * Implementation details: + * + * Time is based off the system timer, and is corrected so that it + * increases by one megabyte per second. This allows for proper + * recycling on high speed LANs while still leaving over an hour + * before rollover. + * + * Two sysctls control the generation of ISNs: + * + * net.inet.tcp.isn_reseed_interval controls the number of seconds + * between seeding of isn_secret. This is normally set to zero, + * as reseeding should not be necessary. + * + * net.inet.tcp.strict_rfc1948 controls whether RFC 1948 is followed + * strictly. When strict compliance is requested, reseeding is + * disabled and SYN-ACKs will be generated in the same manner as + * SYNs. Strict mode is disabled by default. + * + */ - getmicrotime(&time); - read_random(tcp_rndiss_sbox, sizeof(tcp_rndiss_sbox)); +#define ISN_BYTES_PER_SECOND 1048576 - tcp_rndiss_reseed = time.tv_sec + TCP_RNDISS_OUT; - tcp_rndiss_msb = tcp_rndiss_msb == 0x8000 ? 0 : 0x8000; - tcp_rndiss_cnt = 0; -} +u_char isn_secret[32]; +int isn_last_reseed; +MD5_CTX isn_ctx; tcp_seq -tcp_rndiss_next() +tcp_new_isn(tp) + struct tcpcb *tp; { - u_int32_t tmp; - struct timeval time; - - getmicrotime(&time); - - if (tcp_rndiss_cnt >= TCP_RNDISS_MAX || - time.tv_sec > tcp_rndiss_reseed) - tcp_rndiss_init(); - - tmp = random(); + u_int32_t md5_buffer[4]; + tcp_seq new_isn; + struct timeval time; + + /* Use arc4random for SYN-ACKs when not in exact RFC1948 mode. */ + if (((tp->t_state == TCPS_LISTEN) || (tp->t_state == TCPS_TIME_WAIT)) + && tcp_strict_rfc1948 == 0) +#ifdef __APPLE__ + return random(); +#else + return arc4random(); +#endif - /* (tmp & 0x7fff) ensures a 32768 byte gap between ISS */ - return ((tcp_rndiss_encrypt(tcp_rndiss_cnt++) | tcp_rndiss_msb) <<16) | - (tmp & 0x7fff); + /* Seed if this is the first use, reseed if requested. */ + if ((isn_last_reseed == 0) || + ((tcp_strict_rfc1948 == 0) && (tcp_isn_reseed_interval > 0) && + (((u_int)isn_last_reseed + (u_int)tcp_isn_reseed_interval*hz) + < (u_int)time.tv_sec))) { +#ifdef __APPLE__ + read_random(&isn_secret, sizeof(isn_secret)); +#else + read_random_unlimited(&isn_secret, sizeof(isn_secret)); +#endif + isn_last_reseed = time.tv_sec; + } + + /* Compute the md5 hash and return the ISN. */ + MD5Init(&isn_ctx); + MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_fport, sizeof(u_short)); + MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_lport, sizeof(u_short)); +#if INET6 + if ((tp->t_inpcb->inp_vflag & INP_IPV6) != 0) { + MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_faddr, + sizeof(struct in6_addr)); + MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_laddr, + sizeof(struct in6_addr)); + } else +#endif + { + MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_faddr, + sizeof(struct in_addr)); + MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_laddr, + sizeof(struct in_addr)); + } + MD5Update(&isn_ctx, (u_char *) &isn_secret, sizeof(isn_secret)); + MD5Final((u_char *) &md5_buffer, &isn_ctx); + new_isn = (tcp_seq) md5_buffer[0]; + new_isn += time.tv_sec * (ISN_BYTES_PER_SECOND / hz); + return new_isn; } - /* * When a source quench is received, close congestion window * to one segment. We will gradually open it again as we proceed. @@ -1084,6 +1458,22 @@ tcp_quench(inp, errno) tp->snd_cwnd = tp->t_maxseg; } +/* + * When a specific ICMP unreachable message is received and the + * connection state is SYN-SENT, drop the connection. This behavior + * is controlled by the icmp_may_rst sysctl. + */ +void +tcp_drop_syn_sent(inp, errno) + struct inpcb *inp; + int errno; +{ + struct tcpcb *tp = intotcpcb(inp); + + if (tp && tp->t_state == TCPS_SYN_SENT) + tcp_drop(tp, errno); +} + /* * When `need fragmentation' ICMP is received, update our idea of the MSS * based on the new value in the route. Also nudge TCP to send something, @@ -1102,7 +1492,7 @@ tcp_mtudisc(inp, errno) int offered; int mss; #if INET6 - int isipv6 = (tp->t_inpcb->inp_vflag & INP_IPV4) == 0; + int isipv6 = (tp->t_inpcb->inp_vflag & INP_IPV6) != 0; #endif /* INET6 */ if (tp) { @@ -1125,7 +1515,7 @@ tcp_mtudisc(inp, errno) mss = rt->rt_rmx.rmx_mtu - #if INET6 (isipv6 ? - sizeof(struct tcpip6hdr) : + sizeof(struct ip6_hdr) + sizeof(struct tcphdr) : #endif /* INET6 */ sizeof(struct tcpiphdr) #if INET6 @@ -1162,20 +1552,14 @@ tcp_mtudisc(inp, errno) if ((tp->t_flags & (TF_REQ_CC|TF_NOOPT)) == TF_REQ_CC && (tp->t_flags & TF_RCVD_CC) == TF_RCVD_CC) mss -= TCPOLEN_CC_APPA; -#if (MCLBYTES & (MCLBYTES - 1)) == 0 - if (mss > MCLBYTES) - mss &= ~(MCLBYTES-1); -#else - if (mss > MCLBYTES) - mss = mss / MCLBYTES * MCLBYTES; -#endif + if (so->so_snd.sb_hiwat < mss) mss = so->so_snd.sb_hiwat; tp->t_maxseg = mss; tcpstat.tcps_mturesent++; - tp->t_rtt = 0; + tp->t_rtttime = 0; tp->snd_nxt = tp->snd_una; tcp_output(tp); } @@ -1198,11 +1582,11 @@ tcp_rtlookup(inp) if (ro == NULL) return (NULL); rt = ro->ro_rt; - if (rt == NULL || !(rt->rt_flags & RTF_UP)) { + if (rt == NULL || !(rt->rt_flags & RTF_UP) || rt->generation_id != route_generation) { /* No route yet, so try to acquire one */ if (inp->inp_faddr.s_addr != INADDR_ANY) { ro->ro_dst.sa_family = AF_INET; - ro->ro_dst.sa_len = sizeof(ro->ro_dst); + ro->ro_dst.sa_len = sizeof(struct sockaddr_in); ((struct sockaddr_in *) &ro->ro_dst)->sin_addr = inp->inp_faddr; rtalloc(ro); @@ -1225,9 +1609,12 @@ tcp_rtlookup6(inp) if (rt == NULL || !(rt->rt_flags & RTF_UP)) { /* No route yet, so try to acquire one */ if (!IN6_IS_ADDR_UNSPECIFIED(&inp->in6p_faddr)) { - ro6->ro_dst.sin6_family = AF_INET6; - ro6->ro_dst.sin6_len = sizeof(ro6->ro_dst); - ro6->ro_dst.sin6_addr = inp->in6p_faddr; + struct sockaddr_in6 *dst6; + + dst6 = (struct sockaddr_in6 *)&ro6->ro_dst; + dst6->sin6_family = AF_INET6; + dst6->sin6_len = sizeof(*dst6); + dst6->sin6_addr = inp->in6p_faddr; rtalloc((struct route *)ro6); rt = ro6->ro_rt; } @@ -1239,11 +1626,8 @@ tcp_rtlookup6(inp) #if IPSEC /* compute ESP/AH header size for TCP, including outer IP header. */ size_t -ipsec_hdrsiz_tcp(tp, isipv6) +ipsec_hdrsiz_tcp(tp) struct tcpcb *tp; -#if INET6 - int isipv6; -#endif /* INET6 */ { struct inpcb *inp; struct mbuf *m; @@ -1254,40 +1638,31 @@ ipsec_hdrsiz_tcp(tp, isipv6) #endif /* INET6 */ struct tcphdr *th; - if (!tp || !tp->t_template || !(inp = tp->t_inpcb)) + if ((tp == NULL) || ((inp = tp->t_inpcb) == NULL)) return 0; MGETHDR(m, M_DONTWAIT, MT_DATA); if (!m) return 0; - + + lck_mtx_lock(sadb_mutex); #if INET6 - if (isipv6) { + if ((inp->inp_vflag & INP_IPV6) != 0) { ip6 = mtod(m, struct ip6_hdr *); th = (struct tcphdr *)(ip6 + 1); - m->m_pkthdr.len = m->m_len = sizeof(struct tcpip6hdr); - bcopy((caddr_t)&tp->t_template->tt_i6, (caddr_t)ip6, - sizeof(struct ip6_hdr)); - bcopy((caddr_t)&tp->t_template->tt_t, (caddr_t)th, - sizeof(struct tcphdr)); - } else { + m->m_pkthdr.len = m->m_len = + sizeof(struct ip6_hdr) + sizeof(struct tcphdr); + tcp_fillheaders(tp, ip6, th); + hdrsiz = ipsec6_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp); + } else #endif /* INET6 */ + { ip = mtod(m, struct ip *); th = (struct tcphdr *)(ip + 1); m->m_pkthdr.len = m->m_len = sizeof(struct tcpiphdr); - bcopy((caddr_t)&tp->t_template->tt_i, (caddr_t)ip, sizeof(struct ip)); - bcopy((caddr_t)&tp->t_template->tt_t, (caddr_t)th, - sizeof(struct tcphdr)); -#if INET6 - } -#endif /* INET6 */ - -#if INET6 - if (isipv6) - hdrsiz = ipsec6_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp); - else -#endif /* INET6 */ + tcp_fillheaders(tp, ip, th); hdrsiz = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp); - + } + lck_mtx_unlock(sadb_mutex); m_free(m); return hdrsiz; } @@ -1302,13 +1677,10 @@ struct rmxp_tao * tcp_gettaocache(inp) struct inpcb *inp; { -#if INET6 - int isipv6 = (inp->inp_vflag & INP_IPV4) == 0; -#endif /* INET6 */ struct rtentry *rt; #if INET6 - if (isipv6) + if ((inp->inp_vflag & INP_IPV6) != 0) rt = tcp_rtlookup6(inp); else #endif /* INET6 */ @@ -1334,3 +1706,82 @@ static void tcp_cleartaocache() { } + +int +tcp_lock(so, refcount, lr) + struct socket *so; + int refcount; + int lr; +{ + int lr_saved; + if (lr == 0) + lr_saved = (unsigned int) __builtin_return_address(0); + else lr_saved = lr; + + if (so->so_pcb) { + lck_mtx_lock(((struct inpcb *)so->so_pcb)->inpcb_mtx); + } + else { + panic("tcp_lock: so=%x NO PCB! lr=%x\n", so, lr_saved); + lck_mtx_lock(so->so_proto->pr_domain->dom_mtx); + } + + if (so->so_usecount < 0) + panic("tcp_lock: so=%x so_pcb=%x lr=%x ref=%x\n", + so, so->so_pcb, lr_saved, so->so_usecount); + + if (refcount) + so->so_usecount++; + so->lock_lr[so->next_lock_lr] = (u_int32_t *)lr_saved; + so->next_lock_lr = (so->next_lock_lr+1) % SO_LCKDBG_MAX; + return (0); +} + +int +tcp_unlock(so, refcount, lr) + struct socket *so; + int refcount; + int lr; +{ + int lr_saved; + if (lr == 0) + lr_saved = (unsigned int) __builtin_return_address(0); + else lr_saved = lr; + +#ifdef MORE_TCPLOCK_DEBUG + printf("tcp_unlock: so=%x sopcb=%x lock=%x ref=%x lr=%x\n", + so, so->so_pcb, ((struct inpcb *)so->so_pcb)->inpcb_mtx, so->so_usecount, lr_saved); +#endif + if (refcount) + so->so_usecount--; + + if (so->so_usecount < 0) + panic("tcp_unlock: so=%x usecount=%x\n", so, so->so_usecount); + if (so->so_pcb == NULL) + panic("tcp_unlock: so=%x NO PCB usecount=%x lr=%x\n", so, so->so_usecount, lr_saved); + else { + lck_mtx_assert(((struct inpcb *)so->so_pcb)->inpcb_mtx, LCK_MTX_ASSERT_OWNED); + so->unlock_lr[so->next_unlock_lr] = (u_int *)lr_saved; + so->next_unlock_lr = (so->next_unlock_lr+1) % SO_LCKDBG_MAX; + lck_mtx_unlock(((struct inpcb *)so->so_pcb)->inpcb_mtx); + } + return (0); +} + +lck_mtx_t * +tcp_getlock(so, locktype) + struct socket *so; + int locktype; +{ + struct inpcb *inp = sotoinpcb(so); + + if (so->so_pcb) { + if (so->so_usecount < 0) + panic("tcp_getlock: so=%x usecount=%x\n", so, so->so_usecount); + return(inp->inpcb_mtx); + } + else { + panic("tcp_getlock: so=%x NULL so_pcb\n", so); + return (so->so_proto->pr_domain->dom_mtx); + } +}