| File: | netinet/tcp_input.c |
| Warning: | line 3611, column 3 Value stored to 'tp' is never read |
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| 1 | /* $OpenBSD: tcp_input.c,v 1.397 2023/12/01 15:30:47 bluhm Exp $ */ |
| 2 | /* $NetBSD: tcp_input.c,v 1.23 1996/02/13 23:43:44 christos Exp $ */ |
| 3 | |
| 4 | /* |
| 5 | * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1994 |
| 6 | * The Regents of the University of California. All rights reserved. |
| 7 | * |
| 8 | * Redistribution and use in source and binary forms, with or without |
| 9 | * modification, are permitted provided that the following conditions |
| 10 | * are met: |
| 11 | * 1. Redistributions of source code must retain the above copyright |
| 12 | * notice, this list of conditions and the following disclaimer. |
| 13 | * 2. Redistributions in binary form must reproduce the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer in the |
| 15 | * documentation and/or other materials provided with the distribution. |
| 16 | * 3. Neither the name of the University nor the names of its contributors |
| 17 | * may be used to endorse or promote products derived from this software |
| 18 | * without specific prior written permission. |
| 19 | * |
| 20 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 21 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 22 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 23 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 24 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 25 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 26 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 27 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 28 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 29 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 30 | * SUCH DAMAGE. |
| 31 | * |
| 32 | * @(#)COPYRIGHT 1.1 (NRL) 17 January 1995 |
| 33 | * |
| 34 | * NRL grants permission for redistribution and use in source and binary |
| 35 | * forms, with or without modification, of the software and documentation |
| 36 | * created at NRL provided that the following conditions are met: |
| 37 | * |
| 38 | * 1. Redistributions of source code must retain the above copyright |
| 39 | * notice, this list of conditions and the following disclaimer. |
| 40 | * 2. Redistributions in binary form must reproduce the above copyright |
| 41 | * notice, this list of conditions and the following disclaimer in the |
| 42 | * documentation and/or other materials provided with the distribution. |
| 43 | * 3. All advertising materials mentioning features or use of this software |
| 44 | * must display the following acknowledgements: |
| 45 | * This product includes software developed by the University of |
| 46 | * California, Berkeley and its contributors. |
| 47 | * This product includes software developed at the Information |
| 48 | * Technology Division, US Naval Research Laboratory. |
| 49 | * 4. Neither the name of the NRL nor the names of its contributors |
| 50 | * may be used to endorse or promote products derived from this software |
| 51 | * without specific prior written permission. |
| 52 | * |
| 53 | * THE SOFTWARE PROVIDED BY NRL IS PROVIDED BY NRL AND CONTRIBUTORS ``AS |
| 54 | * IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
| 55 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A |
| 56 | * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL NRL OR |
| 57 | * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| 58 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| 59 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| 60 | * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
| 61 | * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
| 62 | * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
| 63 | * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 64 | * |
| 65 | * The views and conclusions contained in the software and documentation |
| 66 | * are those of the authors and should not be interpreted as representing |
| 67 | * official policies, either expressed or implied, of the US Naval |
| 68 | * Research Laboratory (NRL). |
| 69 | */ |
| 70 | |
| 71 | #include "pf.h" |
| 72 | |
| 73 | #include <sys/param.h> |
| 74 | #include <sys/systm.h> |
| 75 | #include <sys/mbuf.h> |
| 76 | #include <sys/protosw.h> |
| 77 | #include <sys/socket.h> |
| 78 | #include <sys/socketvar.h> |
| 79 | #include <sys/timeout.h> |
| 80 | #include <sys/kernel.h> |
| 81 | #include <sys/pool.h> |
| 82 | |
| 83 | #include <net/if.h> |
| 84 | #include <net/if_var.h> |
| 85 | #include <net/route.h> |
| 86 | |
| 87 | #include <netinet/in.h> |
| 88 | #include <netinet/ip.h> |
| 89 | #include <netinet/in_pcb.h> |
| 90 | #include <netinet/ip_var.h> |
| 91 | #include <netinet/tcp.h> |
| 92 | #include <netinet/tcp_fsm.h> |
| 93 | #include <netinet/tcp_seq.h> |
| 94 | #include <netinet/tcp_timer.h> |
| 95 | #include <netinet/tcp_var.h> |
| 96 | #include <netinet/tcp_debug.h> |
| 97 | |
| 98 | #if NPF1 > 0 |
| 99 | #include <net/pfvar.h> |
| 100 | #endif |
| 101 | |
| 102 | struct tcpiphdr tcp_saveti; |
| 103 | |
| 104 | int tcp_mss_adv(struct mbuf *, int); |
| 105 | int tcp_flush_queue(struct tcpcb *); |
| 106 | |
| 107 | #ifdef INET61 |
| 108 | #include <netinet6/in6_var.h> |
| 109 | #include <netinet6/nd6.h> |
| 110 | |
| 111 | struct tcpipv6hdr tcp_saveti6; |
| 112 | |
| 113 | /* for the packet header length in the mbuf */ |
| 114 | #define M_PH_LEN(m)(((struct mbuf *)(m))->M_dat.MH.MH_pkthdr.len) (((struct mbuf *)(m))->m_pkthdrM_dat.MH.MH_pkthdr.len) |
| 115 | #define M_V6_LEN(m)((((struct mbuf *)(m))->M_dat.MH.MH_pkthdr.len) - sizeof(struct ip6_hdr)) (M_PH_LEN(m)(((struct mbuf *)(m))->M_dat.MH.MH_pkthdr.len) - sizeof(struct ip6_hdr)) |
| 116 | #define M_V4_LEN(m)((((struct mbuf *)(m))->M_dat.MH.MH_pkthdr.len) - sizeof(struct ip)) (M_PH_LEN(m)(((struct mbuf *)(m))->M_dat.MH.MH_pkthdr.len) - sizeof(struct ip)) |
| 117 | #endif /* INET6 */ |
| 118 | |
| 119 | int tcprexmtthresh = 3; |
| 120 | int tcptv_keep_init = TCPTV_KEEP_INIT((75) * 1000); |
| 121 | |
| 122 | int tcp_rst_ppslim = 100; /* 100pps */ |
| 123 | int tcp_rst_ppslim_count = 0; |
| 124 | struct timeval tcp_rst_ppslim_last; |
| 125 | |
| 126 | int tcp_ackdrop_ppslim = 100; /* 100pps */ |
| 127 | int tcp_ackdrop_ppslim_count = 0; |
| 128 | struct timeval tcp_ackdrop_ppslim_last; |
| 129 | |
| 130 | #define TCP_PAWS_IDLE((24 * 24 * 60 * 60) * 1000) TCP_TIME(24 * 24 * 60 * 60)((24 * 24 * 60 * 60) * 1000) |
| 131 | |
| 132 | /* for modulo comparisons of timestamps */ |
| 133 | #define TSTMP_LT(a,b)((int32_t)((a)-(b)) < 0) ((int32_t)((a)-(b)) < 0) |
| 134 | #define TSTMP_GEQ(a,b)((int32_t)((a)-(b)) >= 0) ((int32_t)((a)-(b)) >= 0) |
| 135 | |
| 136 | /* for TCP SACK comparisons */ |
| 137 | #define SEQ_MIN(a,b)(((int)((a)-(b)) < 0) ? (a) : (b)) (SEQ_LT(a,b)((int)((a)-(b)) < 0) ? (a) : (b)) |
| 138 | #define SEQ_MAX(a,b)(((int)((a)-(b)) > 0) ? (a) : (b)) (SEQ_GT(a,b)((int)((a)-(b)) > 0) ? (a) : (b)) |
| 139 | |
| 140 | /* |
| 141 | * Neighbor Discovery, Neighbor Unreachability Detection Upper layer hint. |
| 142 | */ |
| 143 | #ifdef INET61 |
| 144 | #define ND6_HINT(tp)do { if (tp && tp->t_inpcb && (tp->t_inpcb ->inp_flags & 0x100) && rtisvalid(tp->t_inpcb ->inp_ru.ru_route6.ro_rt)) { nd6_nud_hint(tp->t_inpcb-> inp_ru.ru_route6.ro_rt); } } while (0) \ |
| 145 | do { \ |
| 146 | if (tp && tp->t_inpcb && (tp->t_inpcb->inp_flags & INP_IPV60x100) && \ |
| 147 | rtisvalid(tp->t_inpcb->inp_route6inp_ru.ru_route6.ro_rt)) { \ |
| 148 | nd6_nud_hint(tp->t_inpcb->inp_route6inp_ru.ru_route6.ro_rt); \ |
| 149 | } \ |
| 150 | } while (0) |
| 151 | #else |
| 152 | #define ND6_HINT(tp)do { if (tp && tp->t_inpcb && (tp->t_inpcb ->inp_flags & 0x100) && rtisvalid(tp->t_inpcb ->inp_ru.ru_route6.ro_rt)) { nd6_nud_hint(tp->t_inpcb-> inp_ru.ru_route6.ro_rt); } } while (0) |
| 153 | #endif |
| 154 | |
| 155 | #ifdef TCP_ECN1 |
| 156 | /* |
| 157 | * ECN (Explicit Congestion Notification) support based on RFC3168 |
| 158 | * implementation note: |
| 159 | * snd_last is used to track a recovery phase. |
| 160 | * when cwnd is reduced, snd_last is set to snd_max. |
| 161 | * while snd_last > snd_una, the sender is in a recovery phase and |
| 162 | * its cwnd should not be reduced again. |
| 163 | * snd_last follows snd_una when not in a recovery phase. |
| 164 | */ |
| 165 | #endif |
| 166 | |
| 167 | /* |
| 168 | * Macro to compute ACK transmission behavior. Delay the ACK unless |
| 169 | * we have already delayed an ACK (must send an ACK every two segments). |
| 170 | * We also ACK immediately if we received a PUSH and the ACK-on-PUSH |
| 171 | * option is enabled or when the packet is coming from a loopback |
| 172 | * interface. |
| 173 | */ |
| 174 | #define TCP_SETUP_ACK(tp, tiflags, m)do { struct ifnet *ifp = ((void *)0); if (m && (m-> m_hdr.mh_flags & 0x0002)) ifp = if_get(m->M_dat.MH.MH_pkthdr .ph_ifidx); if ((((tp)->t_flags) & (0x04000000U << (5))) || (tcp_ack_on_push && (tiflags) & 0x08) || (ifp && (ifp->if_flags & 0x8))) tp->t_flags |= 0x0001U; else do { (((tp)->t_flags) |= (0x04000000U << (5))); timeout_add_msec(&(tp)->t_timer[(5)], (tcp_delack_msecs )); } while (0); if_put(ifp); } while (0) \ |
| 175 | do { \ |
| 176 | struct ifnet *ifp = NULL((void *)0); \ |
| 177 | if (m && (m->m_flagsm_hdr.mh_flags & M_PKTHDR0x0002)) \ |
| 178 | ifp = if_get(m->m_pkthdrM_dat.MH.MH_pkthdr.ph_ifidx); \ |
| 179 | if (TCP_TIMER_ISARMED(tp, TCPT_DELACK)(((tp)->t_flags) & (0x04000000U << (5))) || \ |
| 180 | (tcp_ack_on_push && (tiflags) & TH_PUSH0x08) || \ |
| 181 | (ifp && (ifp->if_flags & IFF_LOOPBACK0x8))) \ |
| 182 | tp->t_flags |= TF_ACKNOW0x0001U; \ |
| 183 | else \ |
| 184 | TCP_TIMER_ARM(tp, TCPT_DELACK, tcp_delack_msecs)do { (((tp)->t_flags) |= (0x04000000U << (5))); timeout_add_msec (&(tp)->t_timer[(5)], (tcp_delack_msecs)); } while (0); \ |
| 185 | if_put(ifp); \ |
| 186 | } while (0) |
| 187 | |
| 188 | void tcp_sack_partialack(struct tcpcb *, struct tcphdr *); |
| 189 | void tcp_newreno_partialack(struct tcpcb *, struct tcphdr *); |
| 190 | |
| 191 | void syn_cache_put(struct syn_cache *); |
| 192 | void syn_cache_rm(struct syn_cache *); |
| 193 | int syn_cache_respond(struct syn_cache *, struct mbuf *, uint64_t); |
| 194 | void syn_cache_timer(void *); |
| 195 | void syn_cache_insert(struct syn_cache *, struct tcpcb *); |
| 196 | void syn_cache_reset(struct sockaddr *, struct sockaddr *, |
| 197 | struct tcphdr *, u_int); |
| 198 | int syn_cache_add(struct sockaddr *, struct sockaddr *, struct tcphdr *, |
| 199 | unsigned int, struct socket *, struct mbuf *, u_char *, int, |
| 200 | struct tcp_opt_info *, tcp_seq *, uint64_t); |
| 201 | struct socket *syn_cache_get(struct sockaddr *, struct sockaddr *, |
| 202 | struct tcphdr *, unsigned int, unsigned int, struct socket *, |
| 203 | struct mbuf *, uint64_t); |
| 204 | struct syn_cache *syn_cache_lookup(struct sockaddr *, struct sockaddr *, |
| 205 | struct syn_cache_head **, u_int); |
| 206 | |
| 207 | /* |
| 208 | * Insert segment ti into reassembly queue of tcp with |
| 209 | * control block tp. Return TH_FIN if reassembly now includes |
| 210 | * a segment with FIN. The macro form does the common case inline |
| 211 | * (segment is the next to be received on an established connection, |
| 212 | * and the queue is empty), avoiding linkage into and removal |
| 213 | * from the queue and repetition of various conversions. |
| 214 | * Set DELACK for segments received in order, but ack immediately |
| 215 | * when segments are out of order (so fast retransmit can work). |
| 216 | */ |
| 217 | |
| 218 | int |
| 219 | tcp_reass(struct tcpcb *tp, struct tcphdr *th, struct mbuf *m, int *tlen) |
| 220 | { |
| 221 | struct tcpqent *p, *q, *nq, *tiqe; |
| 222 | |
| 223 | /* |
| 224 | * Allocate a new queue entry, before we throw away any data. |
| 225 | * If we can't, just drop the packet. XXX |
| 226 | */ |
| 227 | tiqe = pool_get(&tcpqe_pool, PR_NOWAIT0x0002); |
| 228 | if (tiqe == NULL((void *)0)) { |
| 229 | tiqe = TAILQ_LAST(&tp->t_segq, tcpqehead)(*(((struct tcpqehead *)((&tp->t_segq)->tqh_last))-> tqh_last)); |
| 230 | if (tiqe != NULL((void *)0) && th->th_seq == tp->rcv_nxt) { |
| 231 | /* Reuse last entry since new segment fills a hole */ |
| 232 | m_freem(tiqe->tcpqe_m); |
| 233 | TAILQ_REMOVE(&tp->t_segq, tiqe, tcpqe_q)do { if (((tiqe)->tcpqe_q.tqe_next) != ((void *)0)) (tiqe) ->tcpqe_q.tqe_next->tcpqe_q.tqe_prev = (tiqe)->tcpqe_q .tqe_prev; else (&tp->t_segq)->tqh_last = (tiqe)-> tcpqe_q.tqe_prev; *(tiqe)->tcpqe_q.tqe_prev = (tiqe)->tcpqe_q .tqe_next; ((tiqe)->tcpqe_q.tqe_prev) = ((void *)-1); ((tiqe )->tcpqe_q.tqe_next) = ((void *)-1); } while (0); |
| 234 | } |
| 235 | if (tiqe == NULL((void *)0) || th->th_seq != tp->rcv_nxt) { |
| 236 | /* Flush segment queue for this connection */ |
| 237 | tcp_freeq(tp); |
| 238 | tcpstat_inc(tcps_rcvmemdrop); |
| 239 | m_freem(m); |
| 240 | return (0); |
| 241 | } |
| 242 | } |
| 243 | |
| 244 | /* |
| 245 | * Find a segment which begins after this one does. |
| 246 | */ |
| 247 | for (p = NULL((void *)0), q = TAILQ_FIRST(&tp->t_segq)((&tp->t_segq)->tqh_first); q != NULL((void *)0); |
| 248 | p = q, q = TAILQ_NEXT(q, tcpqe_q)((q)->tcpqe_q.tqe_next)) |
| 249 | if (SEQ_GT(q->tcpqe_tcp->th_seq, th->th_seq)((int)((q->tcpqe_tcp->th_seq)-(th->th_seq)) > 0)) |
| 250 | break; |
| 251 | |
| 252 | /* |
| 253 | * If there is a preceding segment, it may provide some of |
| 254 | * our data already. If so, drop the data from the incoming |
| 255 | * segment. If it provides all of our data, drop us. |
| 256 | */ |
| 257 | if (p != NULL((void *)0)) { |
| 258 | struct tcphdr *phdr = p->tcpqe_tcp; |
| 259 | int i; |
| 260 | |
| 261 | /* conversion to int (in i) handles seq wraparound */ |
| 262 | i = phdr->th_seq + phdr->th_reseqlenth_urp - th->th_seq; |
| 263 | if (i > 0) { |
| 264 | if (i >= *tlen) { |
| 265 | tcpstat_pkt(tcps_rcvduppack, tcps_rcvdupbyte, |
| 266 | *tlen); |
| 267 | m_freem(m); |
| 268 | pool_put(&tcpqe_pool, tiqe); |
| 269 | return (0); |
| 270 | } |
| 271 | m_adj(m, i); |
| 272 | *tlen -= i; |
| 273 | th->th_seq += i; |
| 274 | } |
| 275 | } |
| 276 | tcpstat_pkt(tcps_rcvoopack, tcps_rcvoobyte, *tlen); |
| 277 | tp->t_rcvoopack++; |
| 278 | |
| 279 | /* |
| 280 | * While we overlap succeeding segments trim them or, |
| 281 | * if they are completely covered, dequeue them. |
| 282 | */ |
| 283 | for (; q != NULL((void *)0); q = nq) { |
| 284 | struct tcphdr *qhdr = q->tcpqe_tcp; |
| 285 | int i = (th->th_seq + *tlen) - qhdr->th_seq; |
| 286 | |
| 287 | if (i <= 0) |
| 288 | break; |
| 289 | if (i < qhdr->th_reseqlenth_urp) { |
| 290 | qhdr->th_seq += i; |
| 291 | qhdr->th_reseqlenth_urp -= i; |
| 292 | m_adj(q->tcpqe_m, i); |
| 293 | break; |
| 294 | } |
| 295 | nq = TAILQ_NEXT(q, tcpqe_q)((q)->tcpqe_q.tqe_next); |
| 296 | m_freem(q->tcpqe_m); |
| 297 | TAILQ_REMOVE(&tp->t_segq, q, tcpqe_q)do { if (((q)->tcpqe_q.tqe_next) != ((void *)0)) (q)->tcpqe_q .tqe_next->tcpqe_q.tqe_prev = (q)->tcpqe_q.tqe_prev; else (&tp->t_segq)->tqh_last = (q)->tcpqe_q.tqe_prev ; *(q)->tcpqe_q.tqe_prev = (q)->tcpqe_q.tqe_next; ((q)-> tcpqe_q.tqe_prev) = ((void *)-1); ((q)->tcpqe_q.tqe_next) = ((void *)-1); } while (0); |
| 298 | pool_put(&tcpqe_pool, q); |
| 299 | } |
| 300 | |
| 301 | /* Insert the new segment queue entry into place. */ |
| 302 | tiqe->tcpqe_m = m; |
| 303 | th->th_reseqlenth_urp = *tlen; |
| 304 | tiqe->tcpqe_tcp = th; |
| 305 | if (p == NULL((void *)0)) { |
| 306 | TAILQ_INSERT_HEAD(&tp->t_segq, tiqe, tcpqe_q)do { if (((tiqe)->tcpqe_q.tqe_next = (&tp->t_segq)-> tqh_first) != ((void *)0)) (&tp->t_segq)->tqh_first ->tcpqe_q.tqe_prev = &(tiqe)->tcpqe_q.tqe_next; else (&tp->t_segq)->tqh_last = &(tiqe)->tcpqe_q. tqe_next; (&tp->t_segq)->tqh_first = (tiqe); (tiqe) ->tcpqe_q.tqe_prev = &(&tp->t_segq)->tqh_first ; } while (0); |
| 307 | } else { |
| 308 | TAILQ_INSERT_AFTER(&tp->t_segq, p, tiqe, tcpqe_q)do { if (((tiqe)->tcpqe_q.tqe_next = (p)->tcpqe_q.tqe_next ) != ((void *)0)) (tiqe)->tcpqe_q.tqe_next->tcpqe_q.tqe_prev = &(tiqe)->tcpqe_q.tqe_next; else (&tp->t_segq )->tqh_last = &(tiqe)->tcpqe_q.tqe_next; (p)->tcpqe_q .tqe_next = (tiqe); (tiqe)->tcpqe_q.tqe_prev = &(p)-> tcpqe_q.tqe_next; } while (0); |
| 309 | } |
| 310 | |
| 311 | if (th->th_seq != tp->rcv_nxt) |
| 312 | return (0); |
| 313 | |
| 314 | return (tcp_flush_queue(tp)); |
| 315 | } |
| 316 | |
| 317 | int |
| 318 | tcp_flush_queue(struct tcpcb *tp) |
| 319 | { |
| 320 | struct socket *so = tp->t_inpcb->inp_socket; |
| 321 | struct tcpqent *q, *nq; |
| 322 | int flags; |
| 323 | |
| 324 | /* |
| 325 | * Present data to user, advancing rcv_nxt through |
| 326 | * completed sequence space. |
| 327 | */ |
| 328 | if (TCPS_HAVEESTABLISHED(tp->t_state)((tp->t_state) >= 4) == 0) |
| 329 | return (0); |
| 330 | q = TAILQ_FIRST(&tp->t_segq)((&tp->t_segq)->tqh_first); |
| 331 | if (q == NULL((void *)0) || q->tcpqe_tcp->th_seq != tp->rcv_nxt) |
| 332 | return (0); |
| 333 | if (tp->t_state == TCPS_SYN_RECEIVED3 && q->tcpqe_tcp->th_reseqlenth_urp) |
| 334 | return (0); |
| 335 | do { |
| 336 | tp->rcv_nxt += q->tcpqe_tcp->th_reseqlenth_urp; |
| 337 | flags = q->tcpqe_tcp->th_flags & TH_FIN0x01; |
| 338 | |
| 339 | nq = TAILQ_NEXT(q, tcpqe_q)((q)->tcpqe_q.tqe_next); |
| 340 | TAILQ_REMOVE(&tp->t_segq, q, tcpqe_q)do { if (((q)->tcpqe_q.tqe_next) != ((void *)0)) (q)->tcpqe_q .tqe_next->tcpqe_q.tqe_prev = (q)->tcpqe_q.tqe_prev; else (&tp->t_segq)->tqh_last = (q)->tcpqe_q.tqe_prev ; *(q)->tcpqe_q.tqe_prev = (q)->tcpqe_q.tqe_next; ((q)-> tcpqe_q.tqe_prev) = ((void *)-1); ((q)->tcpqe_q.tqe_next) = ((void *)-1); } while (0); |
| 341 | ND6_HINT(tp)do { if (tp && tp->t_inpcb && (tp->t_inpcb ->inp_flags & 0x100) && rtisvalid(tp->t_inpcb ->inp_ru.ru_route6.ro_rt)) { nd6_nud_hint(tp->t_inpcb-> inp_ru.ru_route6.ro_rt); } } while (0); |
| 342 | if (so->so_rcv.sb_state & SS_CANTRCVMORE0x020) |
| 343 | m_freem(q->tcpqe_m); |
| 344 | else |
| 345 | sbappendstream(so, &so->so_rcv, q->tcpqe_m); |
| 346 | pool_put(&tcpqe_pool, q); |
| 347 | q = nq; |
| 348 | } while (q != NULL((void *)0) && q->tcpqe_tcp->th_seq == tp->rcv_nxt); |
| 349 | tp->t_flags |= TF_BLOCKOUTPUT0x01000000U; |
| 350 | sorwakeup(so); |
| 351 | tp->t_flags &= ~TF_BLOCKOUTPUT0x01000000U; |
| 352 | return (flags); |
| 353 | } |
| 354 | |
| 355 | /* |
| 356 | * TCP input routine, follows pages 65-76 of the |
| 357 | * protocol specification dated September, 1981 very closely. |
| 358 | */ |
| 359 | int |
| 360 | tcp_input(struct mbuf **mp, int *offp, int proto, int af) |
| 361 | { |
| 362 | struct mbuf *m = *mp; |
| 363 | int iphlen = *offp; |
| 364 | struct ip *ip = NULL((void *)0); |
| 365 | struct inpcb *inp = NULL((void *)0); |
| 366 | u_int8_t *optp = NULL((void *)0); |
| 367 | int optlen = 0; |
| 368 | int tlen, off; |
| 369 | struct tcpcb *otp = NULL((void *)0), *tp = NULL((void *)0); |
| 370 | int tiflags; |
| 371 | struct socket *so = NULL((void *)0); |
| 372 | int todrop, acked, ourfinisacked; |
| 373 | int hdroptlen = 0; |
| 374 | short ostate; |
| 375 | caddr_t saveti; |
| 376 | tcp_seq iss, *reuse = NULL((void *)0); |
| 377 | uint64_t now; |
| 378 | u_long tiwin; |
| 379 | struct tcp_opt_info opti; |
| 380 | struct tcphdr *th; |
| 381 | #ifdef INET61 |
| 382 | struct ip6_hdr *ip6 = NULL((void *)0); |
| 383 | #endif /* INET6 */ |
| 384 | #ifdef TCP_ECN1 |
| 385 | u_char iptos; |
| 386 | #endif |
| 387 | |
| 388 | tcpstat_inc(tcps_rcvtotal); |
| 389 | |
| 390 | opti.ts_present = 0; |
| 391 | opti.maxseg = 0; |
| 392 | now = tcp_now(); |
| 393 | |
| 394 | /* |
| 395 | * RFC1122 4.2.3.10, p. 104: discard bcast/mcast SYN |
| 396 | */ |
| 397 | if (m->m_flagsm_hdr.mh_flags & (M_BCAST0x0100|M_MCAST0x0200)) |
| 398 | goto drop; |
| 399 | |
| 400 | /* |
| 401 | * Get IP and TCP header together in first mbuf. |
| 402 | * Note: IP leaves IP header in first mbuf. |
| 403 | */ |
| 404 | IP6_EXTHDR_GET(th, struct tcphdr *, m, iphlen, sizeof(*th))do { struct mbuf *t; int tmp; if ((m)->m_hdr.mh_len >= ( iphlen) + (sizeof(*th))) (th) = (struct tcphdr *)(((caddr_t)( ((m))->m_hdr.mh_data)) + (iphlen)); else { t = m_pulldown( (m), (iphlen), (sizeof(*th)), &tmp); if (t) { if (t->m_hdr .mh_len < tmp + (sizeof(*th))) panic("m_pulldown malfunction" ); (th) = (struct tcphdr *)(((caddr_t)((t)->m_hdr.mh_data) ) + tmp); } else { (th) = (struct tcphdr *)((void *)0); (m) = ((void *)0); } } } while ( 0); |
| 405 | if (!th) { |
| 406 | tcpstat_inc(tcps_rcvshort); |
| 407 | return IPPROTO_DONE257; |
| 408 | } |
| 409 | |
| 410 | tlen = m->m_pkthdrM_dat.MH.MH_pkthdr.len - iphlen; |
| 411 | switch (af) { |
| 412 | case AF_INET2: |
| 413 | ip = mtod(m, struct ip *)((struct ip *)((m)->m_hdr.mh_data)); |
| 414 | #ifdef TCP_ECN1 |
| 415 | /* save ip_tos before clearing it for checksum */ |
| 416 | iptos = ip->ip_tos; |
| 417 | #endif |
| 418 | break; |
| 419 | #ifdef INET61 |
| 420 | case AF_INET624: |
| 421 | ip6 = mtod(m, struct ip6_hdr *)((struct ip6_hdr *)((m)->m_hdr.mh_data)); |
| 422 | #ifdef TCP_ECN1 |
| 423 | iptos = (ntohl(ip6->ip6_flow)(__uint32_t)(__builtin_constant_p(ip6->ip6_ctlun.ip6_un1.ip6_un1_flow ) ? (__uint32_t)(((__uint32_t)(ip6->ip6_ctlun.ip6_un1.ip6_un1_flow ) & 0xff) << 24 | ((__uint32_t)(ip6->ip6_ctlun.ip6_un1 .ip6_un1_flow) & 0xff00) << 8 | ((__uint32_t)(ip6-> ip6_ctlun.ip6_un1.ip6_un1_flow) & 0xff0000) >> 8 | ( (__uint32_t)(ip6->ip6_ctlun.ip6_un1.ip6_un1_flow) & 0xff000000 ) >> 24) : __swap32md(ip6->ip6_ctlun.ip6_un1.ip6_un1_flow )) >> 20) & 0xff; |
| 424 | #endif |
| 425 | |
| 426 | /* |
| 427 | * Be proactive about unspecified IPv6 address in source. |
| 428 | * As we use all-zero to indicate unbounded/unconnected pcb, |
| 429 | * unspecified IPv6 address can be used to confuse us. |
| 430 | * |
| 431 | * Note that packets with unspecified IPv6 destination is |
| 432 | * already dropped in ip6_input. |
| 433 | */ |
| 434 | if (IN6_IS_ADDR_UNSPECIFIED(&ip6->ip6_src)((*(const u_int32_t *)(const void *)(&(&ip6->ip6_src )->__u6_addr.__u6_addr8[0]) == 0) && (*(const u_int32_t *)(const void *)(&(&ip6->ip6_src)->__u6_addr.__u6_addr8 [4]) == 0) && (*(const u_int32_t *)(const void *)(& (&ip6->ip6_src)->__u6_addr.__u6_addr8[8]) == 0) && (*(const u_int32_t *)(const void *)(&(&ip6->ip6_src )->__u6_addr.__u6_addr8[12]) == 0))) { |
| 435 | /* XXX stat */ |
| 436 | goto drop; |
| 437 | } |
| 438 | |
| 439 | /* Discard packets to multicast */ |
| 440 | if (IN6_IS_ADDR_MULTICAST(&ip6->ip6_dst)((&ip6->ip6_dst)->__u6_addr.__u6_addr8[0] == 0xff)) { |
| 441 | /* XXX stat */ |
| 442 | goto drop; |
| 443 | } |
| 444 | break; |
| 445 | #endif |
| 446 | default: |
| 447 | unhandled_af(af); |
| 448 | } |
| 449 | |
| 450 | /* |
| 451 | * Checksum extended TCP header and data. |
| 452 | */ |
| 453 | if ((m->m_pkthdrM_dat.MH.MH_pkthdr.csum_flags & M_TCP_CSUM_IN_OK0x0020) == 0) { |
| 454 | int sum; |
| 455 | |
| 456 | if (m->m_pkthdrM_dat.MH.MH_pkthdr.csum_flags & M_TCP_CSUM_IN_BAD0x0040) { |
| 457 | tcpstat_inc(tcps_rcvbadsum); |
| 458 | goto drop; |
| 459 | } |
| 460 | tcpstat_inc(tcps_inswcsum); |
| 461 | switch (af) { |
| 462 | case AF_INET2: |
| 463 | sum = in4_cksum(m, IPPROTO_TCP6, iphlen, tlen); |
| 464 | break; |
| 465 | #ifdef INET61 |
| 466 | case AF_INET624: |
| 467 | sum = in6_cksum(m, IPPROTO_TCP6, sizeof(struct ip6_hdr), |
| 468 | tlen); |
| 469 | break; |
| 470 | #endif |
| 471 | } |
| 472 | if (sum != 0) { |
| 473 | tcpstat_inc(tcps_rcvbadsum); |
| 474 | goto drop; |
| 475 | } |
| 476 | } |
| 477 | |
| 478 | /* |
| 479 | * Check that TCP offset makes sense, |
| 480 | * pull out TCP options and adjust length. XXX |
| 481 | */ |
| 482 | off = th->th_off << 2; |
| 483 | if (off < sizeof(struct tcphdr) || off > tlen) { |
| 484 | tcpstat_inc(tcps_rcvbadoff); |
| 485 | goto drop; |
| 486 | } |
| 487 | tlen -= off; |
| 488 | if (off > sizeof(struct tcphdr)) { |
| 489 | IP6_EXTHDR_GET(th, struct tcphdr *, m, iphlen, off)do { struct mbuf *t; int tmp; if ((m)->m_hdr.mh_len >= ( iphlen) + (off)) (th) = (struct tcphdr *)(((caddr_t)(((m))-> m_hdr.mh_data)) + (iphlen)); else { t = m_pulldown((m), (iphlen ), (off), &tmp); if (t) { if (t->m_hdr.mh_len < tmp + (off)) panic("m_pulldown malfunction"); (th) = (struct tcphdr *)(((caddr_t)((t)->m_hdr.mh_data)) + tmp); } else { (th) = (struct tcphdr *)((void *)0); (m) = ((void *)0); } } } while ( 0); |
| 490 | if (!th) { |
| 491 | tcpstat_inc(tcps_rcvshort); |
| 492 | return IPPROTO_DONE257; |
| 493 | } |
| 494 | optlen = off - sizeof(struct tcphdr); |
| 495 | optp = (u_int8_t *)(th + 1); |
| 496 | /* |
| 497 | * Do quick retrieval of timestamp options ("options |
| 498 | * prediction?"). If timestamp is the only option and it's |
| 499 | * formatted as recommended in RFC 1323 appendix A, we |
| 500 | * quickly get the values now and not bother calling |
| 501 | * tcp_dooptions(), etc. |
| 502 | */ |
| 503 | if ((optlen == TCPOLEN_TSTAMP_APPA(10 +2) || |
| 504 | (optlen > TCPOLEN_TSTAMP_APPA(10 +2) && |
| 505 | optp[TCPOLEN_TSTAMP_APPA(10 +2)] == TCPOPT_EOL0)) && |
| 506 | *(u_int32_t *)optp == htonl(TCPOPT_TSTAMP_HDR)(__uint32_t)(__builtin_constant_p((1<<24|1<<16|8<< 8|10)) ? (__uint32_t)(((__uint32_t)((1<<24|1<<16| 8<<8|10)) & 0xff) << 24 | ((__uint32_t)((1<< 24|1<<16|8<<8|10)) & 0xff00) << 8 | ((__uint32_t )((1<<24|1<<16|8<<8|10)) & 0xff0000) >> 8 | ((__uint32_t)((1<<24|1<<16|8<<8|10)) & 0xff000000) >> 24) : __swap32md((1<<24|1<< 16|8<<8|10))) && |
| 507 | (th->th_flags & TH_SYN0x02) == 0) { |
| 508 | opti.ts_present = 1; |
| 509 | opti.ts_val = ntohl(*(u_int32_t *)(optp + 4))(__uint32_t)(__builtin_constant_p(*(u_int32_t *)(optp + 4)) ? (__uint32_t)(((__uint32_t)(*(u_int32_t *)(optp + 4)) & 0xff ) << 24 | ((__uint32_t)(*(u_int32_t *)(optp + 4)) & 0xff00) << 8 | ((__uint32_t)(*(u_int32_t *)(optp + 4)) & 0xff0000) >> 8 | ((__uint32_t)(*(u_int32_t *)(optp + 4)) & 0xff000000) >> 24) : __swap32md(*(u_int32_t *)(optp + 4))); |
| 510 | opti.ts_ecr = ntohl(*(u_int32_t *)(optp + 8))(__uint32_t)(__builtin_constant_p(*(u_int32_t *)(optp + 8)) ? (__uint32_t)(((__uint32_t)(*(u_int32_t *)(optp + 8)) & 0xff ) << 24 | ((__uint32_t)(*(u_int32_t *)(optp + 8)) & 0xff00) << 8 | ((__uint32_t)(*(u_int32_t *)(optp + 8)) & 0xff0000) >> 8 | ((__uint32_t)(*(u_int32_t *)(optp + 8)) & 0xff000000) >> 24) : __swap32md(*(u_int32_t *)(optp + 8))); |
| 511 | optp = NULL((void *)0); /* we've parsed the options */ |
| 512 | } |
| 513 | } |
| 514 | tiflags = th->th_flags; |
| 515 | |
| 516 | /* |
| 517 | * Convert TCP protocol specific fields to host format. |
| 518 | */ |
| 519 | th->th_seq = ntohl(th->th_seq)(__uint32_t)(__builtin_constant_p(th->th_seq) ? (__uint32_t )(((__uint32_t)(th->th_seq) & 0xff) << 24 | ((__uint32_t )(th->th_seq) & 0xff00) << 8 | ((__uint32_t)(th-> th_seq) & 0xff0000) >> 8 | ((__uint32_t)(th->th_seq ) & 0xff000000) >> 24) : __swap32md(th->th_seq)); |
| 520 | th->th_ack = ntohl(th->th_ack)(__uint32_t)(__builtin_constant_p(th->th_ack) ? (__uint32_t )(((__uint32_t)(th->th_ack) & 0xff) << 24 | ((__uint32_t )(th->th_ack) & 0xff00) << 8 | ((__uint32_t)(th-> th_ack) & 0xff0000) >> 8 | ((__uint32_t)(th->th_ack ) & 0xff000000) >> 24) : __swap32md(th->th_ack)); |
| 521 | th->th_win = ntohs(th->th_win)(__uint16_t)(__builtin_constant_p(th->th_win) ? (__uint16_t )(((__uint16_t)(th->th_win) & 0xffU) << 8 | ((__uint16_t )(th->th_win) & 0xff00U) >> 8) : __swap16md(th-> th_win)); |
| 522 | th->th_urp = ntohs(th->th_urp)(__uint16_t)(__builtin_constant_p(th->th_urp) ? (__uint16_t )(((__uint16_t)(th->th_urp) & 0xffU) << 8 | ((__uint16_t )(th->th_urp) & 0xff00U) >> 8) : __swap16md(th-> th_urp)); |
| 523 | |
| 524 | if (th->th_dport == 0) { |
| 525 | tcpstat_inc(tcps_noport); |
| 526 | goto dropwithreset_ratelim; |
| 527 | } |
| 528 | |
| 529 | /* |
| 530 | * Locate pcb for segment. |
| 531 | */ |
| 532 | #if NPF1 > 0 |
| 533 | inp = pf_inp_lookup(m); |
| 534 | #endif |
| 535 | findpcb: |
| 536 | if (inp == NULL((void *)0)) { |
| 537 | switch (af) { |
| 538 | #ifdef INET61 |
| 539 | case AF_INET624: |
| 540 | inp = in6_pcblookup(&tcbtable, &ip6->ip6_src, |
| 541 | th->th_sport, &ip6->ip6_dst, th->th_dport, |
| 542 | m->m_pkthdrM_dat.MH.MH_pkthdr.ph_rtableid); |
| 543 | break; |
| 544 | #endif |
| 545 | case AF_INET2: |
| 546 | inp = in_pcblookup(&tcbtable, ip->ip_src, |
| 547 | th->th_sport, ip->ip_dst, th->th_dport, |
| 548 | m->m_pkthdrM_dat.MH.MH_pkthdr.ph_rtableid); |
| 549 | break; |
| 550 | } |
| 551 | } |
| 552 | if (inp == NULL((void *)0)) { |
| 553 | tcpstat_inc(tcps_pcbhashmiss); |
| 554 | switch (af) { |
| 555 | #ifdef INET61 |
| 556 | case AF_INET624: |
| 557 | inp = in6_pcblookup_listen(&tcbtable, &ip6->ip6_dst, |
| 558 | th->th_dport, m, m->m_pkthdrM_dat.MH.MH_pkthdr.ph_rtableid); |
| 559 | break; |
| 560 | #endif /* INET6 */ |
| 561 | case AF_INET2: |
| 562 | inp = in_pcblookup_listen(&tcbtable, ip->ip_dst, |
| 563 | th->th_dport, m, m->m_pkthdrM_dat.MH.MH_pkthdr.ph_rtableid); |
| 564 | break; |
| 565 | } |
| 566 | /* |
| 567 | * If the state is CLOSED (i.e., TCB does not exist) then |
| 568 | * all data in the incoming segment is discarded. |
| 569 | * If the TCB exists but is in CLOSED state, it is embryonic, |
| 570 | * but should either do a listen or a connect soon. |
| 571 | */ |
| 572 | } |
| 573 | #ifdef IPSEC1 |
| 574 | if (ipsec_in_use) { |
| 575 | struct m_tag *mtag; |
| 576 | struct tdb *tdb = NULL((void *)0); |
| 577 | int error; |
| 578 | |
| 579 | /* Find most recent IPsec tag */ |
| 580 | mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE0x0001, NULL((void *)0)); |
| 581 | if (mtag != NULL((void *)0)) { |
| 582 | struct tdb_ident *tdbi; |
| 583 | |
| 584 | tdbi = (struct tdb_ident *)(mtag + 1); |
| 585 | tdb = gettdb(tdbi->rdomain, tdbi->spi,gettdb_dir((tdbi->rdomain),(tdbi->spi),(&tdbi->dst ),(tdbi->proto),0) |
| 586 | &tdbi->dst, tdbi->proto)gettdb_dir((tdbi->rdomain),(tdbi->spi),(&tdbi->dst ),(tdbi->proto),0); |
| 587 | } |
| 588 | error = ipsp_spd_lookup(m, af, iphlen, IPSP_DIRECTION_IN0x1, |
| 589 | tdb, inp ? inp->inp_seclevel : NULL((void *)0), NULL((void *)0), NULL((void *)0)); |
| 590 | tdb_unref(tdb); |
| 591 | if (error) { |
| 592 | tcpstat_inc(tcps_rcvnosec); |
| 593 | goto drop; |
| 594 | } |
| 595 | } |
| 596 | #endif /* IPSEC */ |
| 597 | |
| 598 | if (inp == NULL((void *)0)) { |
| 599 | tcpstat_inc(tcps_noport); |
| 600 | goto dropwithreset_ratelim; |
| 601 | } |
| 602 | |
| 603 | KASSERT(sotoinpcb(inp->inp_socket) == inp)((((struct inpcb *)(inp->inp_socket)->so_pcb) == inp) ? (void)0 : __assert("diagnostic ", "/usr/src/sys/netinet/tcp_input.c" , 603, "sotoinpcb(inp->inp_socket) == inp")); |
| 604 | KASSERT(intotcpcb(inp) == NULL || intotcpcb(inp)->t_inpcb == inp)((((struct tcpcb *)(inp)->inp_ppcb) == ((void *)0) || ((struct tcpcb *)(inp)->inp_ppcb)->t_inpcb == inp) ? (void)0 : __assert ("diagnostic ", "/usr/src/sys/netinet/tcp_input.c", 604, "intotcpcb(inp) == NULL || intotcpcb(inp)->t_inpcb == inp" )); |
| 605 | soassertlocked(inp->inp_socket); |
| 606 | |
| 607 | /* Check the minimum TTL for socket. */ |
| 608 | switch (af) { |
| 609 | case AF_INET2: |
| 610 | if (inp->inp_ip_minttl && inp->inp_ip_minttl > ip->ip_ttl) |
| 611 | goto drop; |
| 612 | break; |
| 613 | #ifdef INET61 |
| 614 | case AF_INET624: |
| 615 | if (inp->inp_ip6_minhliminp_ip_minttl && |
| 616 | inp->inp_ip6_minhliminp_ip_minttl > ip6->ip6_hlimip6_ctlun.ip6_un1.ip6_un1_hlim) |
| 617 | goto drop; |
| 618 | break; |
| 619 | #endif |
| 620 | } |
| 621 | |
| 622 | tp = intotcpcb(inp)((struct tcpcb *)(inp)->inp_ppcb); |
| 623 | if (tp == NULL((void *)0)) |
| 624 | goto dropwithreset_ratelim; |
| 625 | if (tp->t_state == TCPS_CLOSED0) |
| 626 | goto drop; |
| 627 | |
| 628 | /* Unscale the window into a 32-bit value. */ |
| 629 | if ((tiflags & TH_SYN0x02) == 0) |
| 630 | tiwin = th->th_win << tp->snd_scale; |
| 631 | else |
| 632 | tiwin = th->th_win; |
| 633 | |
| 634 | so = inp->inp_socket; |
| 635 | if (so->so_options & (SO_DEBUG0x0001|SO_ACCEPTCONN0x0002)) { |
| 636 | union syn_cache_sa src; |
| 637 | union syn_cache_sa dst; |
| 638 | |
| 639 | bzero(&src, sizeof(src))__builtin_bzero((&src), (sizeof(src))); |
| 640 | bzero(&dst, sizeof(dst))__builtin_bzero((&dst), (sizeof(dst))); |
| 641 | switch (af) { |
| 642 | case AF_INET2: |
| 643 | src.sin.sin_len = sizeof(struct sockaddr_in); |
| 644 | src.sin.sin_family = AF_INET2; |
| 645 | src.sin.sin_addr = ip->ip_src; |
| 646 | src.sin.sin_port = th->th_sport; |
| 647 | |
| 648 | dst.sin.sin_len = sizeof(struct sockaddr_in); |
| 649 | dst.sin.sin_family = AF_INET2; |
| 650 | dst.sin.sin_addr = ip->ip_dst; |
| 651 | dst.sin.sin_port = th->th_dport; |
| 652 | break; |
| 653 | #ifdef INET61 |
| 654 | case AF_INET624: |
| 655 | src.sin6.sin6_len = sizeof(struct sockaddr_in6); |
| 656 | src.sin6.sin6_family = AF_INET624; |
| 657 | src.sin6.sin6_addr = ip6->ip6_src; |
| 658 | src.sin6.sin6_port = th->th_sport; |
| 659 | |
| 660 | dst.sin6.sin6_len = sizeof(struct sockaddr_in6); |
| 661 | dst.sin6.sin6_family = AF_INET624; |
| 662 | dst.sin6.sin6_addr = ip6->ip6_dst; |
| 663 | dst.sin6.sin6_port = th->th_dport; |
| 664 | break; |
| 665 | #endif /* INET6 */ |
| 666 | } |
| 667 | |
| 668 | if (so->so_options & SO_DEBUG0x0001) { |
| 669 | otp = tp; |
| 670 | ostate = tp->t_state; |
| 671 | switch (af) { |
| 672 | #ifdef INET61 |
| 673 | case AF_INET624: |
| 674 | saveti = (caddr_t) &tcp_saveti6; |
| 675 | memcpy(&tcp_saveti6.ti6_i, ip6, sizeof(*ip6))__builtin_memcpy((&tcp_saveti6.ti6_i), (ip6), (sizeof(*ip6 ))); |
| 676 | memcpy(&tcp_saveti6.ti6_t, th, sizeof(*th))__builtin_memcpy((&tcp_saveti6.ti6_t), (th), (sizeof(*th) )); |
| 677 | break; |
| 678 | #endif |
| 679 | case AF_INET2: |
| 680 | saveti = (caddr_t) &tcp_saveti; |
| 681 | memcpy(&tcp_saveti.ti_i, ip, sizeof(*ip))__builtin_memcpy((&tcp_saveti.ti_i), (ip), (sizeof(*ip))); |
| 682 | memcpy(&tcp_saveti.ti_t, th, sizeof(*th))__builtin_memcpy((&tcp_saveti.ti_t), (th), (sizeof(*th))); |
| 683 | break; |
| 684 | } |
| 685 | } |
| 686 | if (so->so_options & SO_ACCEPTCONN0x0002) { |
| 687 | switch (tiflags & (TH_RST0x04|TH_SYN0x02|TH_ACK0x10)) { |
| 688 | |
| 689 | case TH_SYN0x02|TH_ACK0x10|TH_RST0x04: |
| 690 | case TH_SYN0x02|TH_RST0x04: |
| 691 | case TH_ACK0x10|TH_RST0x04: |
| 692 | case TH_RST0x04: |
| 693 | syn_cache_reset(&src.sa, &dst.sa, th, |
| 694 | inp->inp_rtableid); |
| 695 | goto drop; |
| 696 | |
| 697 | case TH_SYN0x02|TH_ACK0x10: |
| 698 | /* |
| 699 | * Received a SYN,ACK. This should |
| 700 | * never happen while we are in |
| 701 | * LISTEN. Send an RST. |
| 702 | */ |
| 703 | goto badsyn; |
| 704 | |
| 705 | case TH_ACK0x10: |
| 706 | so = syn_cache_get(&src.sa, &dst.sa, |
| 707 | th, iphlen, tlen, so, m, now); |
| 708 | if (so == NULL((void *)0)) { |
| 709 | /* |
| 710 | * We don't have a SYN for |
| 711 | * this ACK; send an RST. |
| 712 | */ |
| 713 | goto badsyn; |
| 714 | } else if (so == (struct socket *)(-1)) { |
| 715 | /* |
| 716 | * We were unable to create |
| 717 | * the connection. If the |
| 718 | * 3-way handshake was |
| 719 | * completed, and RST has |
| 720 | * been sent to the peer. |
| 721 | * Since the mbuf might be |
| 722 | * in use for the reply, |
| 723 | * do not free it. |
| 724 | */ |
| 725 | m = *mp = NULL((void *)0); |
| 726 | goto drop; |
| 727 | } else { |
| 728 | /* |
| 729 | * We have created a |
| 730 | * full-blown connection. |
| 731 | */ |
| 732 | tp = NULL((void *)0); |
| 733 | in_pcbunref(inp); |
| 734 | inp = in_pcbref(sotoinpcb(so)((struct inpcb *)(so)->so_pcb)); |
| 735 | tp = intotcpcb(inp)((struct tcpcb *)(inp)->inp_ppcb); |
| 736 | if (tp == NULL((void *)0)) |
| 737 | goto badsyn; /*XXX*/ |
| 738 | |
| 739 | } |
| 740 | break; |
| 741 | |
| 742 | default: |
| 743 | /* |
| 744 | * None of RST, SYN or ACK was set. |
| 745 | * This is an invalid packet for a |
| 746 | * TCB in LISTEN state. Send a RST. |
| 747 | */ |
| 748 | goto badsyn; |
| 749 | |
| 750 | case TH_SYN0x02: |
| 751 | /* |
| 752 | * Received a SYN. |
| 753 | */ |
| 754 | #ifdef INET61 |
| 755 | /* |
| 756 | * If deprecated address is forbidden, we do |
| 757 | * not accept SYN to deprecated interface |
| 758 | * address to prevent any new inbound |
| 759 | * connection from getting established. |
| 760 | * When we do not accept SYN, we send a TCP |
| 761 | * RST, with deprecated source address (instead |
| 762 | * of dropping it). We compromise it as it is |
| 763 | * much better for peer to send a RST, and |
| 764 | * RST will be the final packet for the |
| 765 | * exchange. |
| 766 | * |
| 767 | * If we do not forbid deprecated addresses, we |
| 768 | * accept the SYN packet. RFC2462 does not |
| 769 | * suggest dropping SYN in this case. |
| 770 | * If we decipher RFC2462 5.5.4, it says like |
| 771 | * this: |
| 772 | * 1. use of deprecated addr with existing |
| 773 | * communication is okay - "SHOULD continue |
| 774 | * to be used" |
| 775 | * 2. use of it with new communication: |
| 776 | * (2a) "SHOULD NOT be used if alternate |
| 777 | * address with sufficient scope is |
| 778 | * available" |
| 779 | * (2b) nothing mentioned otherwise. |
| 780 | * Here we fall into (2b) case as we have no |
| 781 | * choice in our source address selection - we |
| 782 | * must obey the peer. |
| 783 | * |
| 784 | * The wording in RFC2462 is confusing, and |
| 785 | * there are multiple description text for |
| 786 | * deprecated address handling - worse, they |
| 787 | * are not exactly the same. I believe 5.5.4 |
| 788 | * is the best one, so we follow 5.5.4. |
| 789 | */ |
| 790 | if (ip6 && !ip6_use_deprecated) { |
| 791 | struct in6_ifaddr *ia6; |
| 792 | struct ifnet *ifp = |
| 793 | if_get(m->m_pkthdrM_dat.MH.MH_pkthdr.ph_ifidx); |
| 794 | |
| 795 | if (ifp && |
| 796 | (ia6 = in6ifa_ifpwithaddr(ifp, |
| 797 | &ip6->ip6_dst)) && |
| 798 | (ia6->ia6_flags & |
| 799 | IN6_IFF_DEPRECATED0x10)) { |
| 800 | tp = NULL((void *)0); |
| 801 | if_put(ifp); |
| 802 | goto dropwithreset; |
| 803 | } |
| 804 | if_put(ifp); |
| 805 | } |
| 806 | #endif |
| 807 | |
| 808 | /* |
| 809 | * LISTEN socket received a SYN |
| 810 | * from itself? This can't possibly |
| 811 | * be valid; drop the packet. |
| 812 | */ |
| 813 | if (th->th_dport == th->th_sport) { |
| 814 | switch (af) { |
| 815 | #ifdef INET61 |
| 816 | case AF_INET624: |
| 817 | if (IN6_ARE_ADDR_EQUAL(&ip6->ip6_src,(__builtin_memcmp((&(&ip6->ip6_src)->__u6_addr. __u6_addr8[0]), (&(&ip6->ip6_dst)->__u6_addr.__u6_addr8 [0]), (sizeof(struct in6_addr))) == 0) |
| 818 | &ip6->ip6_dst)(__builtin_memcmp((&(&ip6->ip6_src)->__u6_addr. __u6_addr8[0]), (&(&ip6->ip6_dst)->__u6_addr.__u6_addr8 [0]), (sizeof(struct in6_addr))) == 0)) { |
| 819 | tcpstat_inc(tcps_badsyn); |
| 820 | goto drop; |
| 821 | } |
| 822 | break; |
| 823 | #endif /* INET6 */ |
| 824 | case AF_INET2: |
| 825 | if (ip->ip_dst.s_addr == ip->ip_src.s_addr) { |
| 826 | tcpstat_inc(tcps_badsyn); |
| 827 | goto drop; |
| 828 | } |
| 829 | break; |
| 830 | } |
| 831 | } |
| 832 | |
| 833 | /* |
| 834 | * SYN looks ok; create compressed TCP |
| 835 | * state for it. |
| 836 | */ |
| 837 | if (so->so_qlen > so->so_qlimit || |
| 838 | syn_cache_add(&src.sa, &dst.sa, th, iphlen, |
| 839 | so, m, optp, optlen, &opti, reuse, now) |
| 840 | == -1) { |
| 841 | tcpstat_inc(tcps_dropsyn); |
| 842 | goto drop; |
| 843 | } |
| 844 | in_pcbunref(inp); |
| 845 | return IPPROTO_DONE257; |
| 846 | } |
| 847 | } |
| 848 | } |
| 849 | |
| 850 | #ifdef DIAGNOSTIC1 |
| 851 | /* |
| 852 | * Should not happen now that all embryonic connections |
| 853 | * are handled with compressed state. |
| 854 | */ |
| 855 | if (tp->t_state == TCPS_LISTEN1) |
| 856 | panic("tcp_input: TCPS_LISTEN"); |
| 857 | #endif |
| 858 | |
| 859 | #if NPF1 > 0 |
| 860 | pf_inp_link(m, inp); |
| 861 | #endif |
| 862 | |
| 863 | /* |
| 864 | * Segment received on connection. |
| 865 | * Reset idle time and keep-alive timer. |
| 866 | */ |
| 867 | tp->t_rcvtime = now; |
| 868 | if (TCPS_HAVEESTABLISHED(tp->t_state)((tp->t_state) >= 4)) |
| 869 | TCP_TIMER_ARM(tp, TCPT_KEEP, tcp_keepidle)do { (((tp)->t_flags) |= (0x04000000U << (2))); timeout_add_msec (&(tp)->t_timer[(2)], (tcp_keepidle)); } while (0); |
| 870 | |
| 871 | if (tp->sack_enable) |
| 872 | tcp_del_sackholes(tp, th); /* Delete stale SACK holes */ |
| 873 | |
| 874 | /* |
| 875 | * Process options. |
| 876 | */ |
| 877 | #ifdef TCP_SIGNATURE1 |
| 878 | if (optp || (tp->t_flags & TF_SIGNATURE0x0400U)) |
| 879 | #else |
| 880 | if (optp) |
| 881 | #endif |
| 882 | if (tcp_dooptions(tp, optp, optlen, th, m, iphlen, &opti, |
| 883 | m->m_pkthdrM_dat.MH.MH_pkthdr.ph_rtableid, now)) |
| 884 | goto drop; |
| 885 | |
| 886 | if (opti.ts_present && opti.ts_ecr) { |
| 887 | int32_t rtt_test; |
| 888 | |
| 889 | /* subtract out the tcp timestamp modulator */ |
| 890 | opti.ts_ecr -= tp->ts_modulate; |
| 891 | |
| 892 | /* make sure ts_ecr is sensible */ |
| 893 | rtt_test = now - opti.ts_ecr; |
| 894 | if (rtt_test < 0 || rtt_test > TCP_RTT_MAX(1<<18)) |
| 895 | opti.ts_ecr = 0; |
| 896 | } |
| 897 | |
| 898 | #ifdef TCP_ECN1 |
| 899 | /* if congestion experienced, set ECE bit in subsequent packets. */ |
| 900 | if ((iptos & IPTOS_ECN_MASK0x03) == IPTOS_ECN_CE0x03) { |
| 901 | tp->t_flags |= TF_RCVD_CE0x00010000U; |
| 902 | tcpstat_inc(tcps_ecn_rcvce); |
| 903 | } |
| 904 | #endif |
| 905 | /* |
| 906 | * Header prediction: check for the two common cases |
| 907 | * of a uni-directional data xfer. If the packet has |
| 908 | * no control flags, is in-sequence, the window didn't |
| 909 | * change and we're not retransmitting, it's a |
| 910 | * candidate. If the length is zero and the ack moved |
| 911 | * forward, we're the sender side of the xfer. Just |
| 912 | * free the data acked & wake any higher level process |
| 913 | * that was blocked waiting for space. If the length |
| 914 | * is non-zero and the ack didn't move, we're the |
| 915 | * receiver side. If we're getting packets in-order |
| 916 | * (the reassembly queue is empty), add the data to |
| 917 | * the socket buffer and note that we need a delayed ack. |
| 918 | */ |
| 919 | if (tp->t_state == TCPS_ESTABLISHED4 && |
| 920 | #ifdef TCP_ECN1 |
| 921 | (tiflags & (TH_SYN0x02|TH_FIN0x01|TH_RST0x04|TH_URG0x20|TH_ECE0x40|TH_CWR0x80|TH_ACK0x10)) == TH_ACK0x10 && |
| 922 | #else |
| 923 | (tiflags & (TH_SYN0x02|TH_FIN0x01|TH_RST0x04|TH_URG0x20|TH_ACK0x10)) == TH_ACK0x10 && |
| 924 | #endif |
| 925 | (!opti.ts_present || TSTMP_GEQ(opti.ts_val, tp->ts_recent)((int32_t)((opti.ts_val)-(tp->ts_recent)) >= 0)) && |
| 926 | th->th_seq == tp->rcv_nxt && |
| 927 | tiwin && tiwin == tp->snd_wnd && |
| 928 | tp->snd_nxt == tp->snd_max) { |
| 929 | |
| 930 | /* |
| 931 | * If last ACK falls within this segment's sequence numbers, |
| 932 | * record the timestamp. |
| 933 | * Fix from Braden, see Stevens p. 870 |
| 934 | */ |
| 935 | if (opti.ts_present && SEQ_LEQ(th->th_seq, tp->last_ack_sent)((int)((th->th_seq)-(tp->last_ack_sent)) <= 0)) { |
| 936 | tp->ts_recent_age = now; |
| 937 | tp->ts_recent = opti.ts_val; |
| 938 | } |
| 939 | |
| 940 | if (tlen == 0) { |
| 941 | if (SEQ_GT(th->th_ack, tp->snd_una)((int)((th->th_ack)-(tp->snd_una)) > 0) && |
| 942 | SEQ_LEQ(th->th_ack, tp->snd_max)((int)((th->th_ack)-(tp->snd_max)) <= 0) && |
| 943 | tp->snd_cwnd >= tp->snd_wnd && |
| 944 | tp->t_dupacks == 0) { |
| 945 | /* |
| 946 | * this is a pure ack for outstanding data. |
| 947 | */ |
| 948 | tcpstat_inc(tcps_predack); |
| 949 | if (opti.ts_present && opti.ts_ecr) |
| 950 | tcp_xmit_timer(tp, now - opti.ts_ecr); |
| 951 | else if (tp->t_rtttime && |
| 952 | SEQ_GT(th->th_ack, tp->t_rtseq)((int)((th->th_ack)-(tp->t_rtseq)) > 0)) |
| 953 | tcp_xmit_timer(tp, now - tp->t_rtttime); |
| 954 | acked = th->th_ack - tp->snd_una; |
| 955 | tcpstat_pkt(tcps_rcvackpack, tcps_rcvackbyte, |
| 956 | acked); |
| 957 | tp->t_rcvacktime = now; |
| 958 | ND6_HINT(tp)do { if (tp && tp->t_inpcb && (tp->t_inpcb ->inp_flags & 0x100) && rtisvalid(tp->t_inpcb ->inp_ru.ru_route6.ro_rt)) { nd6_nud_hint(tp->t_inpcb-> inp_ru.ru_route6.ro_rt); } } while (0); |
| 959 | sbdrop(so, &so->so_snd, acked); |
| 960 | |
| 961 | /* |
| 962 | * If we had a pending ICMP message that |
| 963 | * refers to data that have just been |
| 964 | * acknowledged, disregard the recorded ICMP |
| 965 | * message. |
| 966 | */ |
| 967 | if ((tp->t_flags & TF_PMTUD_PEND0x00400000U) && |
| 968 | SEQ_GT(th->th_ack, tp->t_pmtud_th_seq)((int)((th->th_ack)-(tp->t_pmtud_th_seq)) > 0)) |
| 969 | tp->t_flags &= ~TF_PMTUD_PEND0x00400000U; |
| 970 | |
| 971 | /* |
| 972 | * Keep track of the largest chunk of data |
| 973 | * acknowledged since last PMTU update |
| 974 | */ |
| 975 | if (tp->t_pmtud_mss_acked < acked) |
| 976 | tp->t_pmtud_mss_acked = acked; |
| 977 | |
| 978 | tp->snd_una = th->th_ack; |
| 979 | /* Pull snd_wl2 up to prevent seq wrap. */ |
| 980 | tp->snd_wl2 = th->th_ack; |
| 981 | /* |
| 982 | * We want snd_last to track snd_una so |
| 983 | * as to avoid sequence wraparound problems |
| 984 | * for very large transfers. |
| 985 | */ |
| 986 | #ifdef TCP_ECN1 |
| 987 | if (SEQ_GT(tp->snd_una, tp->snd_last)((int)((tp->snd_una)-(tp->snd_last)) > 0)) |
| 988 | #endif |
| 989 | tp->snd_last = tp->snd_una; |
| 990 | m_freem(m); |
| 991 | |
| 992 | /* |
| 993 | * If all outstanding data are acked, stop |
| 994 | * retransmit timer, otherwise restart timer |
| 995 | * using current (possibly backed-off) value. |
| 996 | * If process is waiting for space, |
| 997 | * wakeup/selwakeup/signal. If data |
| 998 | * are ready to send, let tcp_output |
| 999 | * decide between more output or persist. |
| 1000 | */ |
| 1001 | if (tp->snd_una == tp->snd_max) |
| 1002 | TCP_TIMER_DISARM(tp, TCPT_REXMT)do { (((tp)->t_flags) &= ~(0x04000000U << (0))); timeout_del(&(tp)->t_timer[(0)]); } while (0); |
| 1003 | else if (TCP_TIMER_ISARMED(tp, TCPT_PERSIST)(((tp)->t_flags) & (0x04000000U << (1))) == 0) |
| 1004 | TCP_TIMER_ARM(tp, TCPT_REXMT, tp->t_rxtcur)do { (((tp)->t_flags) |= (0x04000000U << (0))); timeout_add_msec (&(tp)->t_timer[(0)], (tp->t_rxtcur)); } while (0); |
| 1005 | |
| 1006 | tcp_update_sndspace(tp); |
| 1007 | if (sb_notify(so, &so->so_snd)) { |
| 1008 | tp->t_flags |= TF_BLOCKOUTPUT0x01000000U; |
| 1009 | sowwakeup(so); |
| 1010 | tp->t_flags &= ~TF_BLOCKOUTPUT0x01000000U; |
| 1011 | } |
| 1012 | if (so->so_snd.sb_cc || |
| 1013 | tp->t_flags & TF_NEEDOUTPUT0x00800000U) |
| 1014 | (void) tcp_output(tp); |
| 1015 | in_pcbunref(inp); |
| 1016 | return IPPROTO_DONE257; |
| 1017 | } |
| 1018 | } else if (th->th_ack == tp->snd_una && |
| 1019 | TAILQ_EMPTY(&tp->t_segq)(((&tp->t_segq)->tqh_first) == ((void *)0)) && |
| 1020 | tlen <= sbspace(so, &so->so_rcv)) { |
| 1021 | /* |
| 1022 | * This is a pure, in-sequence data packet |
| 1023 | * with nothing on the reassembly queue and |
| 1024 | * we have enough buffer space to take it. |
| 1025 | */ |
| 1026 | /* Clean receiver SACK report if present */ |
| 1027 | if (tp->sack_enable && tp->rcv_numsacks) |
| 1028 | tcp_clean_sackreport(tp); |
| 1029 | tcpstat_inc(tcps_preddat); |
| 1030 | tp->rcv_nxt += tlen; |
| 1031 | /* Pull snd_wl1 and rcv_up up to prevent seq wrap. */ |
| 1032 | tp->snd_wl1 = th->th_seq; |
| 1033 | /* Packet has most recent segment, no urgent exists. */ |
| 1034 | tp->rcv_up = tp->rcv_nxt; |
| 1035 | tcpstat_pkt(tcps_rcvpack, tcps_rcvbyte, tlen); |
| 1036 | ND6_HINT(tp)do { if (tp && tp->t_inpcb && (tp->t_inpcb ->inp_flags & 0x100) && rtisvalid(tp->t_inpcb ->inp_ru.ru_route6.ro_rt)) { nd6_nud_hint(tp->t_inpcb-> inp_ru.ru_route6.ro_rt); } } while (0); |
| 1037 | |
| 1038 | TCP_SETUP_ACK(tp, tiflags, m)do { struct ifnet *ifp = ((void *)0); if (m && (m-> m_hdr.mh_flags & 0x0002)) ifp = if_get(m->M_dat.MH.MH_pkthdr .ph_ifidx); if ((((tp)->t_flags) & (0x04000000U << (5))) || (tcp_ack_on_push && (tiflags) & 0x08) || (ifp && (ifp->if_flags & 0x8))) tp->t_flags |= 0x0001U; else do { (((tp)->t_flags) |= (0x04000000U << (5))); timeout_add_msec(&(tp)->t_timer[(5)], (tcp_delack_msecs )); } while (0); if_put(ifp); } while (0); |
| 1039 | /* |
| 1040 | * Drop TCP, IP headers and TCP options then add data |
| 1041 | * to socket buffer. |
| 1042 | */ |
| 1043 | if (so->so_rcv.sb_state & SS_CANTRCVMORE0x020) |
| 1044 | m_freem(m); |
| 1045 | else { |
| 1046 | if (tp->t_srtt != 0 && tp->rfbuf_ts != 0 && |
| 1047 | now - tp->rfbuf_ts > (tp->t_srtt >> |
| 1048 | (TCP_RTT_SHIFT3 + TCP_RTT_BASE_SHIFT2))) { |
| 1049 | tcp_update_rcvspace(tp); |
| 1050 | /* Start over with next RTT. */ |
| 1051 | tp->rfbuf_cnt = 0; |
| 1052 | tp->rfbuf_ts = 0; |
| 1053 | } else |
| 1054 | tp->rfbuf_cnt += tlen; |
| 1055 | m_adj(m, iphlen + off); |
| 1056 | sbappendstream(so, &so->so_rcv, m); |
| 1057 | } |
| 1058 | tp->t_flags |= TF_BLOCKOUTPUT0x01000000U; |
| 1059 | sorwakeup(so); |
| 1060 | tp->t_flags &= ~TF_BLOCKOUTPUT0x01000000U; |
| 1061 | if (tp->t_flags & (TF_ACKNOW0x0001U|TF_NEEDOUTPUT0x00800000U)) |
| 1062 | (void) tcp_output(tp); |
| 1063 | in_pcbunref(inp); |
| 1064 | return IPPROTO_DONE257; |
| 1065 | } |
| 1066 | } |
| 1067 | |
| 1068 | /* |
| 1069 | * Compute mbuf offset to TCP data segment. |
| 1070 | */ |
| 1071 | hdroptlen = iphlen + off; |
| 1072 | |
| 1073 | /* |
| 1074 | * Calculate amount of space in receive window, |
| 1075 | * and then do TCP input processing. |
| 1076 | * Receive window is amount of space in rcv queue, |
| 1077 | * but not less than advertised window. |
| 1078 | */ |
| 1079 | { int win; |
| 1080 | |
| 1081 | win = sbspace(so, &so->so_rcv); |
| 1082 | if (win < 0) |
| 1083 | win = 0; |
| 1084 | tp->rcv_wnd = imax(win, (int)(tp->rcv_adv - tp->rcv_nxt)); |
| 1085 | } |
| 1086 | |
| 1087 | switch (tp->t_state) { |
| 1088 | |
| 1089 | /* |
| 1090 | * If the state is SYN_RECEIVED: |
| 1091 | * if seg contains SYN/ACK, send an RST. |
| 1092 | * if seg contains an ACK, but not for our SYN/ACK, send an RST |
| 1093 | */ |
| 1094 | |
| 1095 | case TCPS_SYN_RECEIVED3: |
| 1096 | if (tiflags & TH_ACK0x10) { |
| 1097 | if (tiflags & TH_SYN0x02) { |
| 1098 | tcpstat_inc(tcps_badsyn); |
| 1099 | goto dropwithreset; |
| 1100 | } |
| 1101 | if (SEQ_LEQ(th->th_ack, tp->snd_una)((int)((th->th_ack)-(tp->snd_una)) <= 0) || |
| 1102 | SEQ_GT(th->th_ack, tp->snd_max)((int)((th->th_ack)-(tp->snd_max)) > 0)) |
| 1103 | goto dropwithreset; |
| 1104 | } |
| 1105 | break; |
| 1106 | |
| 1107 | /* |
| 1108 | * If the state is SYN_SENT: |
| 1109 | * if seg contains an ACK, but not for our SYN, drop the input. |
| 1110 | * if seg contains a RST, then drop the connection. |
| 1111 | * if seg does not contain SYN, then drop it. |
| 1112 | * Otherwise this is an acceptable SYN segment |
| 1113 | * initialize tp->rcv_nxt and tp->irs |
| 1114 | * if seg contains ack then advance tp->snd_una |
| 1115 | * if SYN has been acked change to ESTABLISHED else SYN_RCVD state |
| 1116 | * arrange for segment to be acked (eventually) |
| 1117 | * continue processing rest of data/controls, beginning with URG |
| 1118 | */ |
| 1119 | case TCPS_SYN_SENT2: |
| 1120 | if ((tiflags & TH_ACK0x10) && |
| 1121 | (SEQ_LEQ(th->th_ack, tp->iss)((int)((th->th_ack)-(tp->iss)) <= 0) || |
| 1122 | SEQ_GT(th->th_ack, tp->snd_max)((int)((th->th_ack)-(tp->snd_max)) > 0))) |
| 1123 | goto dropwithreset; |
| 1124 | if (tiflags & TH_RST0x04) { |
| 1125 | #ifdef TCP_ECN1 |
| 1126 | /* if ECN is enabled, fall back to non-ecn at rexmit */ |
| 1127 | if (tcp_do_ecn && !(tp->t_flags & TF_DISABLE_ECN0x00040000U)) |
| 1128 | goto drop; |
| 1129 | #endif |
| 1130 | if (tiflags & TH_ACK0x10) |
| 1131 | tp = tcp_drop(tp, ECONNREFUSED61); |
| 1132 | goto drop; |
| 1133 | } |
| 1134 | if ((tiflags & TH_SYN0x02) == 0) |
| 1135 | goto drop; |
| 1136 | if (tiflags & TH_ACK0x10) { |
| 1137 | tp->snd_una = th->th_ack; |
| 1138 | if (SEQ_LT(tp->snd_nxt, tp->snd_una)((int)((tp->snd_nxt)-(tp->snd_una)) < 0)) |
| 1139 | tp->snd_nxt = tp->snd_una; |
| 1140 | } |
| 1141 | TCP_TIMER_DISARM(tp, TCPT_REXMT)do { (((tp)->t_flags) &= ~(0x04000000U << (0))); timeout_del(&(tp)->t_timer[(0)]); } while (0); |
| 1142 | tp->irs = th->th_seq; |
| 1143 | tcp_mss(tp, opti.maxseg); |
| 1144 | /* Reset initial window to 1 segment for retransmit */ |
| 1145 | if (tp->t_rxtshift > 0) |
| 1146 | tp->snd_cwnd = tp->t_maxseg; |
| 1147 | tcp_rcvseqinit(tp)(tp)->rcv_adv = (tp)->rcv_nxt = (tp)->irs + 1; |
| 1148 | tp->t_flags |= TF_ACKNOW0x0001U; |
| 1149 | /* |
| 1150 | * If we've sent a SACK_PERMITTED option, and the peer |
| 1151 | * also replied with one, then TF_SACK_PERMIT should have |
| 1152 | * been set in tcp_dooptions(). If it was not, disable SACKs. |
| 1153 | */ |
| 1154 | if (tp->sack_enable) |
| 1155 | tp->sack_enable = tp->t_flags & TF_SACK_PERMIT0x0200U; |
| 1156 | #ifdef TCP_ECN1 |
| 1157 | /* |
| 1158 | * if ECE is set but CWR is not set for SYN-ACK, or |
| 1159 | * both ECE and CWR are set for simultaneous open, |
| 1160 | * peer is ECN capable. |
| 1161 | */ |
| 1162 | if (tcp_do_ecn) { |
| 1163 | switch (tiflags & (TH_ACK0x10|TH_ECE0x40|TH_CWR0x80)) { |
| 1164 | case TH_ACK0x10|TH_ECE0x40: |
| 1165 | case TH_ECE0x40|TH_CWR0x80: |
| 1166 | tp->t_flags |= TF_ECN_PERMIT0x00008000U; |
| 1167 | tiflags &= ~(TH_ECE0x40|TH_CWR0x80); |
| 1168 | tcpstat_inc(tcps_ecn_accepts); |
| 1169 | } |
| 1170 | } |
| 1171 | #endif |
| 1172 | |
| 1173 | if (tiflags & TH_ACK0x10 && SEQ_GT(tp->snd_una, tp->iss)((int)((tp->snd_una)-(tp->iss)) > 0)) { |
| 1174 | tcpstat_inc(tcps_connects); |
| 1175 | tp->t_flags |= TF_BLOCKOUTPUT0x01000000U; |
| 1176 | soisconnected(so); |
| 1177 | tp->t_flags &= ~TF_BLOCKOUTPUT0x01000000U; |
| 1178 | tp->t_state = TCPS_ESTABLISHED4; |
| 1179 | TCP_TIMER_ARM(tp, TCPT_KEEP, tcp_keepidle)do { (((tp)->t_flags) |= (0x04000000U << (2))); timeout_add_msec (&(tp)->t_timer[(2)], (tcp_keepidle)); } while (0); |
| 1180 | /* Do window scaling on this connection? */ |
| 1181 | if ((tp->t_flags & (TF_RCVD_SCALE0x0040U|TF_REQ_SCALE0x0020U)) == |
| 1182 | (TF_RCVD_SCALE0x0040U|TF_REQ_SCALE0x0020U)) { |
| 1183 | tp->snd_scale = tp->requested_s_scale; |
| 1184 | tp->rcv_scale = tp->request_r_scale; |
| 1185 | } |
| 1186 | tcp_flush_queue(tp); |
| 1187 | |
| 1188 | /* |
| 1189 | * if we didn't have to retransmit the SYN, |
| 1190 | * use its rtt as our initial srtt & rtt var. |
| 1191 | */ |
| 1192 | if (tp->t_rtttime) |
| 1193 | tcp_xmit_timer(tp, now - tp->t_rtttime); |
| 1194 | /* |
| 1195 | * Since new data was acked (the SYN), open the |
| 1196 | * congestion window by one MSS. We do this |
| 1197 | * here, because we won't go through the normal |
| 1198 | * ACK processing below. And since this is the |
| 1199 | * start of the connection, we know we are in |
| 1200 | * the exponential phase of slow-start. |
| 1201 | */ |
| 1202 | tp->snd_cwnd += tp->t_maxseg; |
| 1203 | } else |
| 1204 | tp->t_state = TCPS_SYN_RECEIVED3; |
| 1205 | |
| 1206 | #if 0 |
| 1207 | trimthenstep6: |
| 1208 | #endif |
| 1209 | /* |
| 1210 | * Advance th->th_seq to correspond to first data byte. |
| 1211 | * If data, trim to stay within window, |
| 1212 | * dropping FIN if necessary. |
| 1213 | */ |
| 1214 | th->th_seq++; |
| 1215 | if (tlen > tp->rcv_wnd) { |
| 1216 | todrop = tlen - tp->rcv_wnd; |
| 1217 | m_adj(m, -todrop); |
| 1218 | tlen = tp->rcv_wnd; |
| 1219 | tiflags &= ~TH_FIN0x01; |
| 1220 | tcpstat_pkt(tcps_rcvpackafterwin, tcps_rcvbyteafterwin, |
| 1221 | todrop); |
| 1222 | } |
| 1223 | tp->snd_wl1 = th->th_seq - 1; |
| 1224 | tp->rcv_up = th->th_seq; |
| 1225 | goto step6; |
| 1226 | /* |
| 1227 | * If a new connection request is received while in TIME_WAIT, |
| 1228 | * drop the old connection and start over if the if the |
| 1229 | * timestamp or the sequence numbers are above the previous |
| 1230 | * ones. |
| 1231 | */ |
| 1232 | case TCPS_TIME_WAIT10: |
| 1233 | if (((tiflags & (TH_SYN0x02|TH_ACK0x10)) == TH_SYN0x02) && |
| 1234 | ((opti.ts_present && |
| 1235 | TSTMP_LT(tp->ts_recent, opti.ts_val)((int32_t)((tp->ts_recent)-(opti.ts_val)) < 0)) || |
| 1236 | SEQ_GT(th->th_seq, tp->rcv_nxt)((int)((th->th_seq)-(tp->rcv_nxt)) > 0))) { |
| 1237 | #if NPF1 > 0 |
| 1238 | /* |
| 1239 | * The socket will be recreated but the new state |
| 1240 | * has already been linked to the socket. Remove the |
| 1241 | * link between old socket and new state. |
| 1242 | */ |
| 1243 | pf_inp_unlink(inp); |
| 1244 | #endif |
| 1245 | /* |
| 1246 | * Advance the iss by at least 32768, but |
| 1247 | * clear the msb in order to make sure |
| 1248 | * that SEG_LT(snd_nxt, iss). |
| 1249 | */ |
| 1250 | iss = tp->snd_nxt + |
| 1251 | ((arc4random() & 0x7fffffff) | 0x8000); |
| 1252 | reuse = &iss; |
| 1253 | tp = tcp_close(tp); |
| 1254 | in_pcbunref(inp); |
| 1255 | inp = NULL((void *)0); |
| 1256 | goto findpcb; |
| 1257 | } |
| 1258 | } |
| 1259 | |
| 1260 | /* |
| 1261 | * States other than LISTEN or SYN_SENT. |
| 1262 | * First check timestamp, if present. |
| 1263 | * Then check that at least some bytes of segment are within |
| 1264 | * receive window. If segment begins before rcv_nxt, |
| 1265 | * drop leading data (and SYN); if nothing left, just ack. |
| 1266 | * |
| 1267 | * RFC 1323 PAWS: If we have a timestamp reply on this segment |
| 1268 | * and it's less than opti.ts_recent, drop it. |
| 1269 | */ |
| 1270 | if (opti.ts_present && (tiflags & TH_RST0x04) == 0 && tp->ts_recent && |
| 1271 | TSTMP_LT(opti.ts_val, tp->ts_recent)((int32_t)((opti.ts_val)-(tp->ts_recent)) < 0)) { |
| 1272 | |
| 1273 | /* Check to see if ts_recent is over 24 days old. */ |
| 1274 | if (now - tp->ts_recent_age > TCP_PAWS_IDLE((24 * 24 * 60 * 60) * 1000)) { |
| 1275 | /* |
| 1276 | * Invalidate ts_recent. If this segment updates |
| 1277 | * ts_recent, the age will be reset later and ts_recent |
| 1278 | * will get a valid value. If it does not, setting |
| 1279 | * ts_recent to zero will at least satisfy the |
| 1280 | * requirement that zero be placed in the timestamp |
| 1281 | * echo reply when ts_recent isn't valid. The |
| 1282 | * age isn't reset until we get a valid ts_recent |
| 1283 | * because we don't want out-of-order segments to be |
| 1284 | * dropped when ts_recent is old. |
| 1285 | */ |
| 1286 | tp->ts_recent = 0; |
| 1287 | } else { |
| 1288 | tcpstat_pkt(tcps_rcvduppack, tcps_rcvdupbyte, tlen); |
| 1289 | tcpstat_inc(tcps_pawsdrop); |
| 1290 | if (tlen) |
| 1291 | goto dropafterack; |
| 1292 | goto drop; |
| 1293 | } |
| 1294 | } |
| 1295 | |
| 1296 | todrop = tp->rcv_nxt - th->th_seq; |
| 1297 | if (todrop > 0) { |
| 1298 | if (tiflags & TH_SYN0x02) { |
| 1299 | tiflags &= ~TH_SYN0x02; |
| 1300 | th->th_seq++; |
| 1301 | if (th->th_urp > 1) |
| 1302 | th->th_urp--; |
| 1303 | else |
| 1304 | tiflags &= ~TH_URG0x20; |
| 1305 | todrop--; |
| 1306 | } |
| 1307 | if (todrop > tlen || |
| 1308 | (todrop == tlen && (tiflags & TH_FIN0x01) == 0)) { |
| 1309 | /* |
| 1310 | * Any valid FIN must be to the left of the |
| 1311 | * window. At this point, FIN must be a |
| 1312 | * duplicate or out-of-sequence, so drop it. |
| 1313 | */ |
| 1314 | tiflags &= ~TH_FIN0x01; |
| 1315 | /* |
| 1316 | * Send ACK to resynchronize, and drop any data, |
| 1317 | * but keep on processing for RST or ACK. |
| 1318 | */ |
| 1319 | tp->t_flags |= TF_ACKNOW0x0001U; |
| 1320 | todrop = tlen; |
| 1321 | tcpstat_pkt(tcps_rcvduppack, tcps_rcvdupbyte, todrop); |
| 1322 | } else { |
| 1323 | tcpstat_pkt(tcps_rcvpartduppack, tcps_rcvpartdupbyte, |
| 1324 | todrop); |
| 1325 | } |
| 1326 | hdroptlen += todrop; /* drop from head afterwards */ |
| 1327 | th->th_seq += todrop; |
| 1328 | tlen -= todrop; |
| 1329 | if (th->th_urp > todrop) |
| 1330 | th->th_urp -= todrop; |
| 1331 | else { |
| 1332 | tiflags &= ~TH_URG0x20; |
| 1333 | th->th_urp = 0; |
| 1334 | } |
| 1335 | } |
| 1336 | |
| 1337 | /* |
| 1338 | * If new data are received on a connection after the |
| 1339 | * user processes are gone, then RST the other end. |
| 1340 | */ |
| 1341 | if ((so->so_state & SS_NOFDREF0x001) && |
| 1342 | tp->t_state > TCPS_CLOSE_WAIT5 && tlen) { |
| 1343 | tp = tcp_close(tp); |
| 1344 | tcpstat_inc(tcps_rcvafterclose); |
| 1345 | goto dropwithreset; |
| 1346 | } |
| 1347 | |
| 1348 | /* |
| 1349 | * If segment ends after window, drop trailing data |
| 1350 | * (and PUSH and FIN); if nothing left, just ACK. |
| 1351 | */ |
| 1352 | todrop = (th->th_seq + tlen) - (tp->rcv_nxt+tp->rcv_wnd); |
| 1353 | if (todrop > 0) { |
| 1354 | tcpstat_inc(tcps_rcvpackafterwin); |
| 1355 | if (todrop >= tlen) { |
| 1356 | tcpstat_add(tcps_rcvbyteafterwin, tlen); |
| 1357 | /* |
| 1358 | * If window is closed can only take segments at |
| 1359 | * window edge, and have to drop data and PUSH from |
| 1360 | * incoming segments. Continue processing, but |
| 1361 | * remember to ack. Otherwise, drop segment |
| 1362 | * and ack. |
| 1363 | */ |
| 1364 | if (tp->rcv_wnd == 0 && th->th_seq == tp->rcv_nxt) { |
| 1365 | tp->t_flags |= TF_ACKNOW0x0001U; |
| 1366 | tcpstat_inc(tcps_rcvwinprobe); |
| 1367 | } else |
| 1368 | goto dropafterack; |
| 1369 | } else |
| 1370 | tcpstat_add(tcps_rcvbyteafterwin, todrop); |
| 1371 | m_adj(m, -todrop); |
| 1372 | tlen -= todrop; |
| 1373 | tiflags &= ~(TH_PUSH0x08|TH_FIN0x01); |
| 1374 | } |
| 1375 | |
| 1376 | /* |
| 1377 | * If last ACK falls within this segment's sequence numbers, |
| 1378 | * record its timestamp if it's more recent. |
| 1379 | * NOTE that the test is modified according to the latest |
| 1380 | * proposal of the tcplw@cray.com list (Braden 1993/04/26). |
| 1381 | */ |
| 1382 | if (opti.ts_present && TSTMP_GEQ(opti.ts_val, tp->ts_recent)((int32_t)((opti.ts_val)-(tp->ts_recent)) >= 0) && |
| 1383 | SEQ_LEQ(th->th_seq, tp->last_ack_sent)((int)((th->th_seq)-(tp->last_ack_sent)) <= 0)) { |
| 1384 | tp->ts_recent_age = now; |
| 1385 | tp->ts_recent = opti.ts_val; |
| 1386 | } |
| 1387 | |
| 1388 | /* |
| 1389 | * If the RST bit is set examine the state: |
| 1390 | * SYN_RECEIVED STATE: |
| 1391 | * If passive open, return to LISTEN state. |
| 1392 | * If active open, inform user that connection was refused. |
| 1393 | * ESTABLISHED, FIN_WAIT_1, FIN_WAIT2, CLOSE_WAIT STATES: |
| 1394 | * Inform user that connection was reset, and close tcb. |
| 1395 | * CLOSING, LAST_ACK, TIME_WAIT STATES |
| 1396 | * Close the tcb. |
| 1397 | */ |
| 1398 | if (tiflags & TH_RST0x04) { |
| 1399 | if (th->th_seq != tp->last_ack_sent && |
| 1400 | th->th_seq != tp->rcv_nxt && |
| 1401 | th->th_seq != (tp->rcv_nxt + 1)) |
| 1402 | goto drop; |
| 1403 | |
| 1404 | switch (tp->t_state) { |
| 1405 | case TCPS_SYN_RECEIVED3: |
| 1406 | #ifdef TCP_ECN1 |
| 1407 | /* if ECN is enabled, fall back to non-ecn at rexmit */ |
| 1408 | if (tcp_do_ecn && !(tp->t_flags & TF_DISABLE_ECN0x00040000U)) |
| 1409 | goto drop; |
| 1410 | #endif |
| 1411 | so->so_error = ECONNREFUSED61; |
| 1412 | goto close; |
| 1413 | |
| 1414 | case TCPS_ESTABLISHED4: |
| 1415 | case TCPS_FIN_WAIT_16: |
| 1416 | case TCPS_FIN_WAIT_29: |
| 1417 | case TCPS_CLOSE_WAIT5: |
| 1418 | so->so_error = ECONNRESET54; |
| 1419 | close: |
| 1420 | tp->t_state = TCPS_CLOSED0; |
| 1421 | tcpstat_inc(tcps_drops); |
| 1422 | tp = tcp_close(tp); |
| 1423 | goto drop; |
| 1424 | case TCPS_CLOSING7: |
| 1425 | case TCPS_LAST_ACK8: |
| 1426 | case TCPS_TIME_WAIT10: |
| 1427 | tp = tcp_close(tp); |
| 1428 | goto drop; |
| 1429 | } |
| 1430 | } |
| 1431 | |
| 1432 | /* |
| 1433 | * If a SYN is in the window, then this is an |
| 1434 | * error and we ACK and drop the packet. |
| 1435 | */ |
| 1436 | if (tiflags & TH_SYN0x02) |
| 1437 | goto dropafterack_ratelim; |
| 1438 | |
| 1439 | /* |
| 1440 | * If the ACK bit is off we drop the segment and return. |
| 1441 | */ |
| 1442 | if ((tiflags & TH_ACK0x10) == 0) { |
| 1443 | if (tp->t_flags & TF_ACKNOW0x0001U) |
| 1444 | goto dropafterack; |
| 1445 | else |
| 1446 | goto drop; |
| 1447 | } |
| 1448 | |
| 1449 | /* |
| 1450 | * Ack processing. |
| 1451 | */ |
| 1452 | switch (tp->t_state) { |
| 1453 | |
| 1454 | /* |
| 1455 | * In SYN_RECEIVED state, the ack ACKs our SYN, so enter |
| 1456 | * ESTABLISHED state and continue processing. |
| 1457 | * The ACK was checked above. |
| 1458 | */ |
| 1459 | case TCPS_SYN_RECEIVED3: |
| 1460 | tcpstat_inc(tcps_connects); |
| 1461 | tp->t_flags |= TF_BLOCKOUTPUT0x01000000U; |
| 1462 | soisconnected(so); |
| 1463 | tp->t_flags &= ~TF_BLOCKOUTPUT0x01000000U; |
| 1464 | tp->t_state = TCPS_ESTABLISHED4; |
| 1465 | TCP_TIMER_ARM(tp, TCPT_KEEP, tcp_keepidle)do { (((tp)->t_flags) |= (0x04000000U << (2))); timeout_add_msec (&(tp)->t_timer[(2)], (tcp_keepidle)); } while (0); |
| 1466 | /* Do window scaling? */ |
| 1467 | if ((tp->t_flags & (TF_RCVD_SCALE0x0040U|TF_REQ_SCALE0x0020U)) == |
| 1468 | (TF_RCVD_SCALE0x0040U|TF_REQ_SCALE0x0020U)) { |
| 1469 | tp->snd_scale = tp->requested_s_scale; |
| 1470 | tp->rcv_scale = tp->request_r_scale; |
| 1471 | tiwin = th->th_win << tp->snd_scale; |
| 1472 | } |
| 1473 | tcp_flush_queue(tp); |
| 1474 | tp->snd_wl1 = th->th_seq - 1; |
| 1475 | /* fall into ... */ |
| 1476 | |
| 1477 | /* |
| 1478 | * In ESTABLISHED state: drop duplicate ACKs; ACK out of range |
| 1479 | * ACKs. If the ack is in the range |
| 1480 | * tp->snd_una < th->th_ack <= tp->snd_max |
| 1481 | * then advance tp->snd_una to th->th_ack and drop |
| 1482 | * data from the retransmission queue. If this ACK reflects |
| 1483 | * more up to date window information we update our window information. |
| 1484 | */ |
| 1485 | case TCPS_ESTABLISHED4: |
| 1486 | case TCPS_FIN_WAIT_16: |
| 1487 | case TCPS_FIN_WAIT_29: |
| 1488 | case TCPS_CLOSE_WAIT5: |
| 1489 | case TCPS_CLOSING7: |
| 1490 | case TCPS_LAST_ACK8: |
| 1491 | case TCPS_TIME_WAIT10: |
| 1492 | #ifdef TCP_ECN1 |
| 1493 | /* |
| 1494 | * if we receive ECE and are not already in recovery phase, |
| 1495 | * reduce cwnd by half but don't slow-start. |
| 1496 | * advance snd_last to snd_max not to reduce cwnd again |
| 1497 | * until all outstanding packets are acked. |
| 1498 | */ |
| 1499 | if (tcp_do_ecn && (tiflags & TH_ECE0x40)) { |
| 1500 | if ((tp->t_flags & TF_ECN_PERMIT0x00008000U) && |
| 1501 | SEQ_GEQ(tp->snd_una, tp->snd_last)((int)((tp->snd_una)-(tp->snd_last)) >= 0)) { |
| 1502 | u_int win; |
| 1503 | |
| 1504 | win = min(tp->snd_wnd, tp->snd_cwnd) / tp->t_maxseg; |
| 1505 | if (win > 1) { |
| 1506 | tp->snd_ssthresh = win / 2 * tp->t_maxseg; |
| 1507 | tp->snd_cwnd = tp->snd_ssthresh; |
| 1508 | tp->snd_last = tp->snd_max; |
| 1509 | tp->t_flags |= TF_SEND_CWR0x00020000U; |
| 1510 | tcpstat_inc(tcps_cwr_ecn); |
| 1511 | } |
| 1512 | } |
| 1513 | tcpstat_inc(tcps_ecn_rcvece); |
| 1514 | } |
| 1515 | /* |
| 1516 | * if we receive CWR, we know that the peer has reduced |
| 1517 | * its congestion window. stop sending ecn-echo. |
| 1518 | */ |
| 1519 | if ((tiflags & TH_CWR0x80)) { |
| 1520 | tp->t_flags &= ~TF_RCVD_CE0x00010000U; |
| 1521 | tcpstat_inc(tcps_ecn_rcvcwr); |
| 1522 | } |
| 1523 | #endif /* TCP_ECN */ |
| 1524 | |
| 1525 | if (SEQ_LEQ(th->th_ack, tp->snd_una)((int)((th->th_ack)-(tp->snd_una)) <= 0)) { |
| 1526 | /* |
| 1527 | * Duplicate/old ACK processing. |
| 1528 | * Increments t_dupacks: |
| 1529 | * Pure duplicate (same seq/ack/window, no data) |
| 1530 | * Doesn't affect t_dupacks: |
| 1531 | * Data packets. |
| 1532 | * Normal window updates (window opens) |
| 1533 | * Resets t_dupacks: |
| 1534 | * New data ACKed. |
| 1535 | * Window shrinks |
| 1536 | * Old ACK |
| 1537 | */ |
| 1538 | if (tlen) { |
| 1539 | /* Drop very old ACKs unless th_seq matches */ |
| 1540 | if (th->th_seq != tp->rcv_nxt && |
| 1541 | SEQ_LT(th->th_ack,((int)((th->th_ack)-(tp->snd_una - tp->max_sndwnd)) < 0) |
| 1542 | tp->snd_una - tp->max_sndwnd)((int)((th->th_ack)-(tp->snd_una - tp->max_sndwnd)) < 0)) { |
| 1543 | tcpstat_inc(tcps_rcvacktooold); |
| 1544 | goto drop; |
| 1545 | } |
| 1546 | break; |
| 1547 | } |
| 1548 | /* |
| 1549 | * If we get an old ACK, there is probably packet |
| 1550 | * reordering going on. Be conservative and reset |
| 1551 | * t_dupacks so that we are less aggressive in |
| 1552 | * doing a fast retransmit. |
| 1553 | */ |
| 1554 | if (th->th_ack != tp->snd_una) { |
| 1555 | tp->t_dupacks = 0; |
| 1556 | break; |
| 1557 | } |
| 1558 | if (tiwin == tp->snd_wnd) { |
| 1559 | tcpstat_inc(tcps_rcvdupack); |
| 1560 | /* |
| 1561 | * If we have outstanding data (other than |
| 1562 | * a window probe), this is a completely |
| 1563 | * duplicate ack (ie, window info didn't |
| 1564 | * change), the ack is the biggest we've |
| 1565 | * seen and we've seen exactly our rexmt |
| 1566 | * threshold of them, assume a packet |
| 1567 | * has been dropped and retransmit it. |
| 1568 | * Kludge snd_nxt & the congestion |
| 1569 | * window so we send only this one |
| 1570 | * packet. |
| 1571 | * |
| 1572 | * We know we're losing at the current |
| 1573 | * window size so do congestion avoidance |
| 1574 | * (set ssthresh to half the current window |
| 1575 | * and pull our congestion window back to |
| 1576 | * the new ssthresh). |
| 1577 | * |
| 1578 | * Dup acks mean that packets have left the |
| 1579 | * network (they're now cached at the receiver) |
| 1580 | * so bump cwnd by the amount in the receiver |
| 1581 | * to keep a constant cwnd packets in the |
| 1582 | * network. |
| 1583 | */ |
| 1584 | if (TCP_TIMER_ISARMED(tp, TCPT_REXMT)(((tp)->t_flags) & (0x04000000U << (0))) == 0) |
| 1585 | tp->t_dupacks = 0; |
| 1586 | else if (++tp->t_dupacks == tcprexmtthresh) { |
| 1587 | tcp_seq onxt = tp->snd_nxt; |
| 1588 | u_long win = |
| 1589 | ulmin(tp->snd_wnd, tp->snd_cwnd) / |
| 1590 | 2 / tp->t_maxseg; |
| 1591 | |
| 1592 | if (SEQ_LT(th->th_ack, tp->snd_last)((int)((th->th_ack)-(tp->snd_last)) < 0)){ |
| 1593 | /* |
| 1594 | * False fast retx after |
| 1595 | * timeout. Do not cut window. |
| 1596 | */ |
| 1597 | tp->t_dupacks = 0; |
| 1598 | goto drop; |
| 1599 | } |
| 1600 | if (win < 2) |
| 1601 | win = 2; |
| 1602 | tp->snd_ssthresh = win * tp->t_maxseg; |
| 1603 | tp->snd_last = tp->snd_max; |
| 1604 | if (tp->sack_enable) { |
| 1605 | TCP_TIMER_DISARM(tp, TCPT_REXMT)do { (((tp)->t_flags) &= ~(0x04000000U << (0))); timeout_del(&(tp)->t_timer[(0)]); } while (0); |
| 1606 | tp->t_rtttime = 0; |
| 1607 | #ifdef TCP_ECN1 |
| 1608 | tp->t_flags |= TF_SEND_CWR0x00020000U; |
| 1609 | #endif |
| 1610 | tcpstat_inc(tcps_cwr_frecovery); |
| 1611 | tcpstat_inc(tcps_sack_recovery_episode); |
| 1612 | /* |
| 1613 | * tcp_output() will send |
| 1614 | * oldest SACK-eligible rtx. |
| 1615 | */ |
| 1616 | (void) tcp_output(tp); |
| 1617 | tp->snd_cwnd = tp->snd_ssthresh+ |
| 1618 | tp->t_maxseg * tp->t_dupacks; |
| 1619 | goto drop; |
| 1620 | } |
| 1621 | TCP_TIMER_DISARM(tp, TCPT_REXMT)do { (((tp)->t_flags) &= ~(0x04000000U << (0))); timeout_del(&(tp)->t_timer[(0)]); } while (0); |
| 1622 | tp->t_rtttime = 0; |
| 1623 | tp->snd_nxt = th->th_ack; |
| 1624 | tp->snd_cwnd = tp->t_maxseg; |
| 1625 | #ifdef TCP_ECN1 |
| 1626 | tp->t_flags |= TF_SEND_CWR0x00020000U; |
| 1627 | #endif |
| 1628 | tcpstat_inc(tcps_cwr_frecovery); |
| 1629 | tcpstat_inc(tcps_sndrexmitfast); |
| 1630 | (void) tcp_output(tp); |
| 1631 | |
| 1632 | tp->snd_cwnd = tp->snd_ssthresh + |
| 1633 | tp->t_maxseg * tp->t_dupacks; |
| 1634 | if (SEQ_GT(onxt, tp->snd_nxt)((int)((onxt)-(tp->snd_nxt)) > 0)) |
| 1635 | tp->snd_nxt = onxt; |
| 1636 | goto drop; |
| 1637 | } else if (tp->t_dupacks > tcprexmtthresh) { |
| 1638 | tp->snd_cwnd += tp->t_maxseg; |
| 1639 | (void) tcp_output(tp); |
| 1640 | goto drop; |
| 1641 | } |
| 1642 | } else if (tiwin < tp->snd_wnd) { |
| 1643 | /* |
| 1644 | * The window was retracted! Previous dup |
| 1645 | * ACKs may have been due to packets arriving |
| 1646 | * after the shrunken window, not a missing |
| 1647 | * packet, so play it safe and reset t_dupacks |
| 1648 | */ |
| 1649 | tp->t_dupacks = 0; |
| 1650 | } |
| 1651 | break; |
| 1652 | } |
| 1653 | /* |
| 1654 | * If the congestion window was inflated to account |
| 1655 | * for the other side's cached packets, retract it. |
| 1656 | */ |
| 1657 | if (tp->t_dupacks >= tcprexmtthresh) { |
| 1658 | /* Check for a partial ACK */ |
| 1659 | if (SEQ_LT(th->th_ack, tp->snd_last)((int)((th->th_ack)-(tp->snd_last)) < 0)) { |
| 1660 | if (tp->sack_enable) |
| 1661 | tcp_sack_partialack(tp, th); |
| 1662 | else |
| 1663 | tcp_newreno_partialack(tp, th); |
| 1664 | } else { |
| 1665 | /* Out of fast recovery */ |
| 1666 | tp->snd_cwnd = tp->snd_ssthresh; |
| 1667 | if (tcp_seq_subtract(tp->snd_max, th->th_ack) < |
| 1668 | tp->snd_ssthresh) |
| 1669 | tp->snd_cwnd = |
| 1670 | tcp_seq_subtract(tp->snd_max, |
| 1671 | th->th_ack); |
| 1672 | tp->t_dupacks = 0; |
| 1673 | } |
| 1674 | } else { |
| 1675 | /* |
| 1676 | * Reset the duplicate ACK counter if we |
| 1677 | * were not in fast recovery. |
| 1678 | */ |
| 1679 | tp->t_dupacks = 0; |
| 1680 | } |
| 1681 | if (SEQ_GT(th->th_ack, tp->snd_max)((int)((th->th_ack)-(tp->snd_max)) > 0)) { |
| 1682 | tcpstat_inc(tcps_rcvacktoomuch); |
| 1683 | goto dropafterack_ratelim; |
| 1684 | } |
| 1685 | acked = th->th_ack - tp->snd_una; |
| 1686 | tcpstat_pkt(tcps_rcvackpack, tcps_rcvackbyte, acked); |
| 1687 | tp->t_rcvacktime = now; |
| 1688 | |
| 1689 | /* |
| 1690 | * If we have a timestamp reply, update smoothed |
| 1691 | * round trip time. If no timestamp is present but |
| 1692 | * transmit timer is running and timed sequence |
| 1693 | * number was acked, update smoothed round trip time. |
| 1694 | * Since we now have an rtt measurement, cancel the |
| 1695 | * timer backoff (cf., Phil Karn's retransmit alg.). |
| 1696 | * Recompute the initial retransmit timer. |
| 1697 | */ |
| 1698 | if (opti.ts_present && opti.ts_ecr) |
| 1699 | tcp_xmit_timer(tp, now - opti.ts_ecr); |
| 1700 | else if (tp->t_rtttime && SEQ_GT(th->th_ack, tp->t_rtseq)((int)((th->th_ack)-(tp->t_rtseq)) > 0)) |
| 1701 | tcp_xmit_timer(tp, now - tp->t_rtttime); |
| 1702 | |
| 1703 | /* |
| 1704 | * If all outstanding data is acked, stop retransmit |
| 1705 | * timer and remember to restart (more output or persist). |
| 1706 | * If there is more data to be acked, restart retransmit |
| 1707 | * timer, using current (possibly backed-off) value. |
| 1708 | */ |
| 1709 | if (th->th_ack == tp->snd_max) { |
| 1710 | TCP_TIMER_DISARM(tp, TCPT_REXMT)do { (((tp)->t_flags) &= ~(0x04000000U << (0))); timeout_del(&(tp)->t_timer[(0)]); } while (0); |
| 1711 | tp->t_flags |= TF_NEEDOUTPUT0x00800000U; |
| 1712 | } else if (TCP_TIMER_ISARMED(tp, TCPT_PERSIST)(((tp)->t_flags) & (0x04000000U << (1))) == 0) |
| 1713 | TCP_TIMER_ARM(tp, TCPT_REXMT, tp->t_rxtcur)do { (((tp)->t_flags) |= (0x04000000U << (0))); timeout_add_msec (&(tp)->t_timer[(0)], (tp->t_rxtcur)); } while (0); |
| 1714 | /* |
| 1715 | * When new data is acked, open the congestion window. |
| 1716 | * If the window gives us less than ssthresh packets |
| 1717 | * in flight, open exponentially (maxseg per packet). |
| 1718 | * Otherwise open linearly: maxseg per window |
| 1719 | * (maxseg^2 / cwnd per packet). |
| 1720 | */ |
| 1721 | { |
| 1722 | u_int cw = tp->snd_cwnd; |
| 1723 | u_int incr = tp->t_maxseg; |
| 1724 | |
| 1725 | if (cw > tp->snd_ssthresh) |
| 1726 | incr = max(incr * incr / cw, 1); |
| 1727 | if (tp->t_dupacks < tcprexmtthresh) |
| 1728 | tp->snd_cwnd = ulmin(cw + incr, |
| 1729 | TCP_MAXWIN65535 << tp->snd_scale); |
| 1730 | } |
| 1731 | ND6_HINT(tp)do { if (tp && tp->t_inpcb && (tp->t_inpcb ->inp_flags & 0x100) && rtisvalid(tp->t_inpcb ->inp_ru.ru_route6.ro_rt)) { nd6_nud_hint(tp->t_inpcb-> inp_ru.ru_route6.ro_rt); } } while (0); |
| 1732 | if (acked > so->so_snd.sb_cc) { |
| 1733 | if (tp->snd_wnd > so->so_snd.sb_cc) |
| 1734 | tp->snd_wnd -= so->so_snd.sb_cc; |
| 1735 | else |
| 1736 | tp->snd_wnd = 0; |
| 1737 | sbdrop(so, &so->so_snd, (int)so->so_snd.sb_cc); |
| 1738 | ourfinisacked = 1; |
| 1739 | } else { |
| 1740 | sbdrop(so, &so->so_snd, acked); |
| 1741 | if (tp->snd_wnd > acked) |
| 1742 | tp->snd_wnd -= acked; |
| 1743 | else |
| 1744 | tp->snd_wnd = 0; |
| 1745 | ourfinisacked = 0; |
| 1746 | } |
| 1747 | |
| 1748 | tcp_update_sndspace(tp); |
| 1749 | if (sb_notify(so, &so->so_snd)) { |
| 1750 | tp->t_flags |= TF_BLOCKOUTPUT0x01000000U; |
| 1751 | sowwakeup(so); |
| 1752 | tp->t_flags &= ~TF_BLOCKOUTPUT0x01000000U; |
| 1753 | } |
| 1754 | |
| 1755 | /* |
| 1756 | * If we had a pending ICMP message that referred to data |
| 1757 | * that have just been acknowledged, disregard the recorded |
| 1758 | * ICMP message. |
| 1759 | */ |
| 1760 | if ((tp->t_flags & TF_PMTUD_PEND0x00400000U) && |
| 1761 | SEQ_GT(th->th_ack, tp->t_pmtud_th_seq)((int)((th->th_ack)-(tp->t_pmtud_th_seq)) > 0)) |
| 1762 | tp->t_flags &= ~TF_PMTUD_PEND0x00400000U; |
| 1763 | |
| 1764 | /* |
| 1765 | * Keep track of the largest chunk of data acknowledged |
| 1766 | * since last PMTU update |
| 1767 | */ |
| 1768 | if (tp->t_pmtud_mss_acked < acked) |
| 1769 | tp->t_pmtud_mss_acked = acked; |
| 1770 | |
| 1771 | tp->snd_una = th->th_ack; |
| 1772 | #ifdef TCP_ECN1 |
| 1773 | /* sync snd_last with snd_una */ |
| 1774 | if (SEQ_GT(tp->snd_una, tp->snd_last)((int)((tp->snd_una)-(tp->snd_last)) > 0)) |
| 1775 | tp->snd_last = tp->snd_una; |
| 1776 | #endif |
| 1777 | if (SEQ_LT(tp->snd_nxt, tp->snd_una)((int)((tp->snd_nxt)-(tp->snd_una)) < 0)) |
| 1778 | tp->snd_nxt = tp->snd_una; |
| 1779 | |
| 1780 | switch (tp->t_state) { |
| 1781 | |
| 1782 | /* |
| 1783 | * In FIN_WAIT_1 STATE in addition to the processing |
| 1784 | * for the ESTABLISHED state if our FIN is now acknowledged |
| 1785 | * then enter FIN_WAIT_2. |
| 1786 | */ |
| 1787 | case TCPS_FIN_WAIT_16: |
| 1788 | if (ourfinisacked) { |
| 1789 | /* |
| 1790 | * If we can't receive any more |
| 1791 | * data, then closing user can proceed. |
| 1792 | * Starting the timer is contrary to the |
| 1793 | * specification, but if we don't get a FIN |
| 1794 | * we'll hang forever. |
| 1795 | */ |
| 1796 | if (so->so_rcv.sb_state & SS_CANTRCVMORE0x020) { |
| 1797 | tp->t_flags |= TF_BLOCKOUTPUT0x01000000U; |
| 1798 | soisdisconnected(so); |
| 1799 | tp->t_flags &= ~TF_BLOCKOUTPUT0x01000000U; |
| 1800 | TCP_TIMER_ARM(tp, TCPT_2MSL, tcp_maxidle)do { (((tp)->t_flags) |= (0x04000000U << (3))); timeout_add_msec (&(tp)->t_timer[(3)], (tcp_maxidle)); } while (0); |
| 1801 | } |
| 1802 | tp->t_state = TCPS_FIN_WAIT_29; |
| 1803 | } |
| 1804 | break; |
| 1805 | |
| 1806 | /* |
| 1807 | * In CLOSING STATE in addition to the processing for |
| 1808 | * the ESTABLISHED state if the ACK acknowledges our FIN |
| 1809 | * then enter the TIME-WAIT state, otherwise ignore |
| 1810 | * the segment. |
| 1811 | */ |
| 1812 | case TCPS_CLOSING7: |
| 1813 | if (ourfinisacked) { |
| 1814 | tp->t_state = TCPS_TIME_WAIT10; |
| 1815 | tcp_canceltimers(tp); |
| 1816 | TCP_TIMER_ARM(tp, TCPT_2MSL, 2 * TCPTV_MSL)do { (((tp)->t_flags) |= (0x04000000U << (3))); timeout_add_msec (&(tp)->t_timer[(3)], (2 * ((30) * 1000))); } while (0 ); |
| 1817 | tp->t_flags |= TF_BLOCKOUTPUT0x01000000U; |
| 1818 | soisdisconnected(so); |
| 1819 | tp->t_flags &= ~TF_BLOCKOUTPUT0x01000000U; |
| 1820 | } |
| 1821 | break; |
| 1822 | |
| 1823 | /* |
| 1824 | * In LAST_ACK, we may still be waiting for data to drain |
| 1825 | * and/or to be acked, as well as for the ack of our FIN. |
| 1826 | * If our FIN is now acknowledged, delete the TCB, |
| 1827 | * enter the closed state and return. |
| 1828 | */ |
| 1829 | case TCPS_LAST_ACK8: |
| 1830 | if (ourfinisacked) { |
| 1831 | tp = tcp_close(tp); |
| 1832 | goto drop; |
| 1833 | } |
| 1834 | break; |
| 1835 | |
| 1836 | /* |
| 1837 | * In TIME_WAIT state the only thing that should arrive |
| 1838 | * is a retransmission of the remote FIN. Acknowledge |
| 1839 | * it and restart the finack timer. |
| 1840 | */ |
| 1841 | case TCPS_TIME_WAIT10: |
| 1842 | TCP_TIMER_ARM(tp, TCPT_2MSL, 2 * TCPTV_MSL)do { (((tp)->t_flags) |= (0x04000000U << (3))); timeout_add_msec (&(tp)->t_timer[(3)], (2 * ((30) * 1000))); } while (0 ); |
| 1843 | goto dropafterack; |
| 1844 | } |
| 1845 | } |
| 1846 | |
| 1847 | step6: |
| 1848 | /* |
| 1849 | * Update window information. |
| 1850 | * Don't look at window if no ACK: TAC's send garbage on first SYN. |
| 1851 | */ |
| 1852 | if ((tiflags & TH_ACK0x10) && |
| 1853 | (SEQ_LT(tp->snd_wl1, th->th_seq)((int)((tp->snd_wl1)-(th->th_seq)) < 0) || (tp->snd_wl1 == th->th_seq && |
| 1854 | (SEQ_LT(tp->snd_wl2, th->th_ack)((int)((tp->snd_wl2)-(th->th_ack)) < 0) || |
| 1855 | (tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd))))) { |
| 1856 | /* keep track of pure window updates */ |
| 1857 | if (tlen == 0 && |
| 1858 | tp->snd_wl2 == th->th_ack && tiwin > tp->snd_wnd) |
| 1859 | tcpstat_inc(tcps_rcvwinupd); |
| 1860 | tp->snd_wnd = tiwin; |
| 1861 | tp->snd_wl1 = th->th_seq; |
| 1862 | tp->snd_wl2 = th->th_ack; |
| 1863 | if (tp->snd_wnd > tp->max_sndwnd) |
| 1864 | tp->max_sndwnd = tp->snd_wnd; |
| 1865 | tp->t_flags |= TF_NEEDOUTPUT0x00800000U; |
| 1866 | } |
| 1867 | |
| 1868 | /* |
| 1869 | * Process segments with URG. |
| 1870 | */ |
| 1871 | if ((tiflags & TH_URG0x20) && th->th_urp && |
| 1872 | TCPS_HAVERCVDFIN(tp->t_state)((tp->t_state) >= 10) == 0) { |
| 1873 | /* |
| 1874 | * This is a kludge, but if we receive and accept |
| 1875 | * random urgent pointers, we'll crash in |
| 1876 | * soreceive. It's hard to imagine someone |
| 1877 | * actually wanting to send this much urgent data. |
| 1878 | */ |
| 1879 | if (th->th_urp + so->so_rcv.sb_cc > sb_max) { |
| 1880 | th->th_urp = 0; /* XXX */ |
| 1881 | tiflags &= ~TH_URG0x20; /* XXX */ |
| 1882 | goto dodata; /* XXX */ |
| 1883 | } |
| 1884 | /* |
| 1885 | * If this segment advances the known urgent pointer, |
| 1886 | * then mark the data stream. This should not happen |
| 1887 | * in CLOSE_WAIT, CLOSING, LAST_ACK or TIME_WAIT STATES since |
| 1888 | * a FIN has been received from the remote side. |
| 1889 | * In these states we ignore the URG. |
| 1890 | * |
| 1891 | * According to RFC961 (Assigned Protocols), |
| 1892 | * the urgent pointer points to the last octet |
| 1893 | * of urgent data. We continue, however, |
| 1894 | * to consider it to indicate the first octet |
| 1895 | * of data past the urgent section as the original |
| 1896 | * spec states (in one of two places). |
| 1897 | */ |
| 1898 | if (SEQ_GT(th->th_seq+th->th_urp, tp->rcv_up)((int)((th->th_seq+th->th_urp)-(tp->rcv_up)) > 0)) { |
| 1899 | tp->rcv_up = th->th_seq + th->th_urp; |
| 1900 | so->so_oobmark = so->so_rcv.sb_cc + |
| 1901 | (tp->rcv_up - tp->rcv_nxt) - 1; |
| 1902 | if (so->so_oobmark == 0) |
| 1903 | so->so_rcv.sb_state |= SS_RCVATMARK0x040; |
| 1904 | sohasoutofband(so); |
| 1905 | tp->t_oobflags &= ~(TCPOOB_HAVEDATA0x01 | TCPOOB_HADDATA0x02); |
| 1906 | } |
| 1907 | /* |
| 1908 | * Remove out of band data so doesn't get presented to user. |
| 1909 | * This can happen independent of advancing the URG pointer, |
| 1910 | * but if two URG's are pending at once, some out-of-band |
| 1911 | * data may creep in... ick. |
| 1912 | */ |
| 1913 | if (th->th_urp <= (u_int16_t) tlen && |
| 1914 | (so->so_options & SO_OOBINLINE0x0100) == 0) |
| 1915 | tcp_pulloutofband(so, th->th_urp, m, hdroptlen); |
| 1916 | } else |
| 1917 | /* |
| 1918 | * If no out of band data is expected, |
| 1919 | * pull receive urgent pointer along |
| 1920 | * with the receive window. |
| 1921 | */ |
| 1922 | if (SEQ_GT(tp->rcv_nxt, tp->rcv_up)((int)((tp->rcv_nxt)-(tp->rcv_up)) > 0)) |
| 1923 | tp->rcv_up = tp->rcv_nxt; |
| 1924 | dodata: /* XXX */ |
| 1925 | |
| 1926 | /* |
| 1927 | * Process the segment text, merging it into the TCP sequencing queue, |
| 1928 | * and arranging for acknowledgment of receipt if necessary. |
| 1929 | * This process logically involves adjusting tp->rcv_wnd as data |
| 1930 | * is presented to the user (this happens in tcp_usrreq.c, |
| 1931 | * case PRU_RCVD). If a FIN has already been received on this |
| 1932 | * connection then we just ignore the text. |
| 1933 | */ |
| 1934 | if ((tlen || (tiflags & TH_FIN0x01)) && |
| 1935 | TCPS_HAVERCVDFIN(tp->t_state)((tp->t_state) >= 10) == 0) { |
| 1936 | tcp_seq laststart = th->th_seq; |
| 1937 | tcp_seq lastend = th->th_seq + tlen; |
| 1938 | |
| 1939 | if (th->th_seq == tp->rcv_nxt && TAILQ_EMPTY(&tp->t_segq)(((&tp->t_segq)->tqh_first) == ((void *)0)) && |
| 1940 | tp->t_state == TCPS_ESTABLISHED4) { |
| 1941 | TCP_SETUP_ACK(tp, tiflags, m)do { struct ifnet *ifp = ((void *)0); if (m && (m-> m_hdr.mh_flags & 0x0002)) ifp = if_get(m->M_dat.MH.MH_pkthdr .ph_ifidx); if ((((tp)->t_flags) & (0x04000000U << (5))) || (tcp_ack_on_push && (tiflags) & 0x08) || (ifp && (ifp->if_flags & 0x8))) tp->t_flags |= 0x0001U; else do { (((tp)->t_flags) |= (0x04000000U << (5))); timeout_add_msec(&(tp)->t_timer[(5)], (tcp_delack_msecs )); } while (0); if_put(ifp); } while (0); |
| 1942 | tp->rcv_nxt += tlen; |
| 1943 | tiflags = th->th_flags & TH_FIN0x01; |
| 1944 | tcpstat_pkt(tcps_rcvpack, tcps_rcvbyte, tlen); |
| 1945 | ND6_HINT(tp)do { if (tp && tp->t_inpcb && (tp->t_inpcb ->inp_flags & 0x100) && rtisvalid(tp->t_inpcb ->inp_ru.ru_route6.ro_rt)) { nd6_nud_hint(tp->t_inpcb-> inp_ru.ru_route6.ro_rt); } } while (0); |
| 1946 | if (so->so_rcv.sb_state & SS_CANTRCVMORE0x020) |
| 1947 | m_freem(m); |
| 1948 | else { |
| 1949 | m_adj(m, hdroptlen); |
| 1950 | sbappendstream(so, &so->so_rcv, m); |
| 1951 | } |
| 1952 | tp->t_flags |= TF_BLOCKOUTPUT0x01000000U; |
| 1953 | sorwakeup(so); |
| 1954 | tp->t_flags &= ~TF_BLOCKOUTPUT0x01000000U; |
| 1955 | } else { |
| 1956 | m_adj(m, hdroptlen); |
| 1957 | tiflags = tcp_reass(tp, th, m, &tlen); |
| 1958 | tp->t_flags |= TF_ACKNOW0x0001U; |
| 1959 | } |
| 1960 | if (tp->sack_enable) |
| 1961 | tcp_update_sack_list(tp, laststart, lastend); |
| 1962 | |
| 1963 | /* |
| 1964 | * variable len never referenced again in modern BSD, |
| 1965 | * so why bother computing it ?? |
| 1966 | */ |
| 1967 | #if 0 |
| 1968 | /* |
| 1969 | * Note the amount of data that peer has sent into |
| 1970 | * our window, in order to estimate the sender's |
| 1971 | * buffer size. |
| 1972 | */ |
| 1973 | len = so->so_rcv.sb_hiwat - (tp->rcv_adv - tp->rcv_nxt); |
| 1974 | #endif /* 0 */ |
| 1975 | } else { |
| 1976 | m_freem(m); |
| 1977 | tiflags &= ~TH_FIN0x01; |
| 1978 | } |
| 1979 | |
| 1980 | /* |
| 1981 | * If FIN is received ACK the FIN and let the user know |
| 1982 | * that the connection is closing. Ignore a FIN received before |
| 1983 | * the connection is fully established. |
| 1984 | */ |
| 1985 | if ((tiflags & TH_FIN0x01) && TCPS_HAVEESTABLISHED(tp->t_state)((tp->t_state) >= 4)) { |
| 1986 | if (TCPS_HAVERCVDFIN(tp->t_state)((tp->t_state) >= 10) == 0) { |
| 1987 | tp->t_flags |= TF_BLOCKOUTPUT0x01000000U; |
| 1988 | socantrcvmore(so); |
| 1989 | tp->t_flags &= ~TF_BLOCKOUTPUT0x01000000U; |
| 1990 | tp->t_flags |= TF_ACKNOW0x0001U; |
| 1991 | tp->rcv_nxt++; |
| 1992 | } |
| 1993 | switch (tp->t_state) { |
| 1994 | |
| 1995 | /* |
| 1996 | * In ESTABLISHED STATE enter the CLOSE_WAIT state. |
| 1997 | */ |
| 1998 | case TCPS_ESTABLISHED4: |
| 1999 | tp->t_state = TCPS_CLOSE_WAIT5; |
| 2000 | break; |
| 2001 | |
| 2002 | /* |
| 2003 | * If still in FIN_WAIT_1 STATE FIN has not been acked so |
| 2004 | * enter the CLOSING state. |
| 2005 | */ |
| 2006 | case TCPS_FIN_WAIT_16: |
| 2007 | tp->t_state = TCPS_CLOSING7; |
| 2008 | break; |
| 2009 | |
| 2010 | /* |
| 2011 | * In FIN_WAIT_2 state enter the TIME_WAIT state, |
| 2012 | * starting the time-wait timer, turning off the other |
| 2013 | * standard timers. |
| 2014 | */ |
| 2015 | case TCPS_FIN_WAIT_29: |
| 2016 | tp->t_state = TCPS_TIME_WAIT10; |
| 2017 | tcp_canceltimers(tp); |
| 2018 | TCP_TIMER_ARM(tp, TCPT_2MSL, 2 * TCPTV_MSL)do { (((tp)->t_flags) |= (0x04000000U << (3))); timeout_add_msec (&(tp)->t_timer[(3)], (2 * ((30) * 1000))); } while (0 ); |
| 2019 | tp->t_flags |= TF_BLOCKOUTPUT0x01000000U; |
| 2020 | soisdisconnected(so); |
| 2021 | tp->t_flags &= ~TF_BLOCKOUTPUT0x01000000U; |
| 2022 | break; |
| 2023 | |
| 2024 | /* |
| 2025 | * In TIME_WAIT state restart the 2 MSL time_wait timer. |
| 2026 | */ |
| 2027 | case TCPS_TIME_WAIT10: |
| 2028 | TCP_TIMER_ARM(tp, TCPT_2MSL, 2 * TCPTV_MSL)do { (((tp)->t_flags) |= (0x04000000U << (3))); timeout_add_msec (&(tp)->t_timer[(3)], (2 * ((30) * 1000))); } while (0 ); |
| 2029 | break; |
| 2030 | } |
| 2031 | } |
| 2032 | if (otp) |
| 2033 | tcp_trace(TA_INPUT0, ostate, tp, otp, saveti, 0, tlen); |
| 2034 | |
| 2035 | /* |
| 2036 | * Return any desired output. |
| 2037 | */ |
| 2038 | if (tp->t_flags & (TF_ACKNOW0x0001U|TF_NEEDOUTPUT0x00800000U)) |
| 2039 | (void) tcp_output(tp); |
| 2040 | in_pcbunref(inp); |
| 2041 | return IPPROTO_DONE257; |
| 2042 | |
| 2043 | badsyn: |
| 2044 | /* |
| 2045 | * Received a bad SYN. Increment counters and dropwithreset. |
| 2046 | */ |
| 2047 | tcpstat_inc(tcps_badsyn); |
| 2048 | tp = NULL((void *)0); |
| 2049 | goto dropwithreset; |
| 2050 | |
| 2051 | dropafterack_ratelim: |
| 2052 | if (ppsratecheck(&tcp_ackdrop_ppslim_last, &tcp_ackdrop_ppslim_count, |
| 2053 | tcp_ackdrop_ppslim) == 0) { |
| 2054 | /* XXX stat */ |
| 2055 | goto drop; |
| 2056 | } |
| 2057 | /* ...fall into dropafterack... */ |
| 2058 | |
| 2059 | dropafterack: |
| 2060 | /* |
| 2061 | * Generate an ACK dropping incoming segment if it occupies |
| 2062 | * sequence space, where the ACK reflects our state. |
| 2063 | */ |
| 2064 | if (tiflags & TH_RST0x04) |
| 2065 | goto drop; |
| 2066 | m_freem(m); |
| 2067 | tp->t_flags |= TF_ACKNOW0x0001U; |
| 2068 | (void) tcp_output(tp); |
| 2069 | in_pcbunref(inp); |
| 2070 | return IPPROTO_DONE257; |
| 2071 | |
| 2072 | dropwithreset_ratelim: |
| 2073 | /* |
| 2074 | * We may want to rate-limit RSTs in certain situations, |
| 2075 | * particularly if we are sending an RST in response to |
| 2076 | * an attempt to connect to or otherwise communicate with |
| 2077 | * a port for which we have no socket. |
| 2078 | */ |
| 2079 | if (ppsratecheck(&tcp_rst_ppslim_last, &tcp_rst_ppslim_count, |
| 2080 | tcp_rst_ppslim) == 0) { |
| 2081 | /* XXX stat */ |
| 2082 | goto drop; |
| 2083 | } |
| 2084 | /* ...fall into dropwithreset... */ |
| 2085 | |
| 2086 | dropwithreset: |
| 2087 | /* |
| 2088 | * Generate a RST, dropping incoming segment. |
| 2089 | * Make ACK acceptable to originator of segment. |
| 2090 | * Don't bother to respond to RST. |
| 2091 | */ |
| 2092 | if (tiflags & TH_RST0x04) |
| 2093 | goto drop; |
| 2094 | if (tiflags & TH_ACK0x10) { |
| 2095 | tcp_respond(tp, mtod(m, caddr_t)((caddr_t)((m)->m_hdr.mh_data)), th, (tcp_seq)0, th->th_ack, |
| 2096 | TH_RST0x04, m->m_pkthdrM_dat.MH.MH_pkthdr.ph_rtableid, now); |
| 2097 | } else { |
| 2098 | if (tiflags & TH_SYN0x02) |
| 2099 | tlen++; |
| 2100 | tcp_respond(tp, mtod(m, caddr_t)((caddr_t)((m)->m_hdr.mh_data)), th, th->th_seq + tlen, |
| 2101 | (tcp_seq)0, TH_RST0x04|TH_ACK0x10, m->m_pkthdrM_dat.MH.MH_pkthdr.ph_rtableid, now); |
| 2102 | } |
| 2103 | m_freem(m); |
| 2104 | in_pcbunref(inp); |
| 2105 | return IPPROTO_DONE257; |
| 2106 | |
| 2107 | drop: |
| 2108 | /* |
| 2109 | * Drop space held by incoming segment and return. |
| 2110 | */ |
| 2111 | if (otp) |
| 2112 | tcp_trace(TA_DROP4, ostate, tp, otp, saveti, 0, tlen); |
| 2113 | |
| 2114 | m_freem(m); |
| 2115 | in_pcbunref(inp); |
| 2116 | return IPPROTO_DONE257; |
| 2117 | } |
| 2118 | |
| 2119 | int |
| 2120 | tcp_dooptions(struct tcpcb *tp, u_char *cp, int cnt, struct tcphdr *th, |
| 2121 | struct mbuf *m, int iphlen, struct tcp_opt_info *oi, |
| 2122 | u_int rtableid, uint64_t now) |
| 2123 | { |
| 2124 | u_int16_t mss = 0; |
| 2125 | int opt, optlen; |
| 2126 | #ifdef TCP_SIGNATURE1 |
| 2127 | caddr_t sigp = NULL((void *)0); |
| 2128 | struct tdb *tdb = NULL((void *)0); |
| 2129 | #endif /* TCP_SIGNATURE */ |
| 2130 | |
| 2131 | for (; cp && cnt > 0; cnt -= optlen, cp += optlen) { |
| 2132 | opt = cp[0]; |
| 2133 | if (opt == TCPOPT_EOL0) |
| 2134 | break; |
| 2135 | if (opt == TCPOPT_NOP1) |
| 2136 | optlen = 1; |
| 2137 | else { |
| 2138 | if (cnt < 2) |
| 2139 | break; |
| 2140 | optlen = cp[1]; |
| 2141 | if (optlen < 2 || optlen > cnt) |
| 2142 | break; |
| 2143 | } |
| 2144 | switch (opt) { |
| 2145 | |
| 2146 | default: |
| 2147 | continue; |
| 2148 | |
| 2149 | case TCPOPT_MAXSEG2: |
| 2150 | if (optlen != TCPOLEN_MAXSEG4) |
| 2151 | continue; |
| 2152 | if (!(th->th_flags & TH_SYN0x02)) |
| 2153 | continue; |
| 2154 | if (TCPS_HAVERCVDSYN(tp->t_state)((tp->t_state) >= 3)) |
| 2155 | continue; |
| 2156 | memcpy(&mss, cp + 2, sizeof(mss))__builtin_memcpy((&mss), (cp + 2), (sizeof(mss))); |
| 2157 | mss = ntohs(mss)(__uint16_t)(__builtin_constant_p(mss) ? (__uint16_t)(((__uint16_t )(mss) & 0xffU) << 8 | ((__uint16_t)(mss) & 0xff00U ) >> 8) : __swap16md(mss)); |
| 2158 | oi->maxseg = mss; |
| 2159 | break; |
| 2160 | |
| 2161 | case TCPOPT_WINDOW3: |
| 2162 | if (optlen != TCPOLEN_WINDOW3) |
| 2163 | continue; |
| 2164 | if (!(th->th_flags & TH_SYN0x02)) |
| 2165 | continue; |
| 2166 | if (TCPS_HAVERCVDSYN(tp->t_state)((tp->t_state) >= 3)) |
| 2167 | continue; |
| 2168 | tp->t_flags |= TF_RCVD_SCALE0x0040U; |
| 2169 | tp->requested_s_scale = min(cp[2], TCP_MAX_WINSHIFT14); |
| 2170 | break; |
| 2171 | |
| 2172 | case TCPOPT_TIMESTAMP8: |
| 2173 | if (optlen != TCPOLEN_TIMESTAMP10) |
| 2174 | continue; |
| 2175 | oi->ts_present = 1; |
| 2176 | memcpy(&oi->ts_val, cp + 2, sizeof(oi->ts_val))__builtin_memcpy((&oi->ts_val), (cp + 2), (sizeof(oi-> ts_val))); |
| 2177 | oi->ts_val = ntohl(oi->ts_val)(__uint32_t)(__builtin_constant_p(oi->ts_val) ? (__uint32_t )(((__uint32_t)(oi->ts_val) & 0xff) << 24 | ((__uint32_t )(oi->ts_val) & 0xff00) << 8 | ((__uint32_t)(oi-> ts_val) & 0xff0000) >> 8 | ((__uint32_t)(oi->ts_val ) & 0xff000000) >> 24) : __swap32md(oi->ts_val)); |
| 2178 | memcpy(&oi->ts_ecr, cp + 6, sizeof(oi->ts_ecr))__builtin_memcpy((&oi->ts_ecr), (cp + 6), (sizeof(oi-> ts_ecr))); |
| 2179 | oi->ts_ecr = ntohl(oi->ts_ecr)(__uint32_t)(__builtin_constant_p(oi->ts_ecr) ? (__uint32_t )(((__uint32_t)(oi->ts_ecr) & 0xff) << 24 | ((__uint32_t )(oi->ts_ecr) & 0xff00) << 8 | ((__uint32_t)(oi-> ts_ecr) & 0xff0000) >> 8 | ((__uint32_t)(oi->ts_ecr ) & 0xff000000) >> 24) : __swap32md(oi->ts_ecr)); |
| 2180 | |
| 2181 | if (!(th->th_flags & TH_SYN0x02)) |
| 2182 | continue; |
| 2183 | if (TCPS_HAVERCVDSYN(tp->t_state)((tp->t_state) >= 3)) |
| 2184 | continue; |
| 2185 | /* |
| 2186 | * A timestamp received in a SYN makes |
| 2187 | * it ok to send timestamp requests and replies. |
| 2188 | */ |
| 2189 | tp->t_flags |= TF_RCVD_TSTMP0x0100U; |
| 2190 | tp->ts_recent = oi->ts_val; |
| 2191 | tp->ts_recent_age = now; |
| 2192 | break; |
| 2193 | |
| 2194 | case TCPOPT_SACK_PERMITTED4: |
| 2195 | if (!tp->sack_enable || optlen!=TCPOLEN_SACK_PERMITTED2) |
| 2196 | continue; |
| 2197 | if (!(th->th_flags & TH_SYN0x02)) |
| 2198 | continue; |
| 2199 | if (TCPS_HAVERCVDSYN(tp->t_state)((tp->t_state) >= 3)) |
| 2200 | continue; |
| 2201 | /* MUST only be set on SYN */ |
| 2202 | tp->t_flags |= TF_SACK_PERMIT0x0200U; |
| 2203 | break; |
| 2204 | case TCPOPT_SACK5: |
| 2205 | tcp_sack_option(tp, th, cp, optlen); |
| 2206 | break; |
| 2207 | #ifdef TCP_SIGNATURE1 |
| 2208 | case TCPOPT_SIGNATURE19: |
| 2209 | if (optlen != TCPOLEN_SIGNATURE18) |
| 2210 | continue; |
| 2211 | |
| 2212 | if (sigp && timingsafe_bcmp(sigp, cp + 2, 16)) |
| 2213 | goto bad; |
| 2214 | |
| 2215 | sigp = cp + 2; |
| 2216 | break; |
| 2217 | #endif /* TCP_SIGNATURE */ |
| 2218 | } |
| 2219 | } |
| 2220 | |
| 2221 | #ifdef TCP_SIGNATURE1 |
| 2222 | if (tp->t_flags & TF_SIGNATURE0x0400U) { |
| 2223 | union sockaddr_union src, dst; |
| 2224 | |
| 2225 | memset(&src, 0, sizeof(union sockaddr_union))__builtin_memset((&src), (0), (sizeof(union sockaddr_union ))); |
| 2226 | memset(&dst, 0, sizeof(union sockaddr_union))__builtin_memset((&dst), (0), (sizeof(union sockaddr_union ))); |
| 2227 | |
| 2228 | switch (tp->pf) { |
| 2229 | case 0: |
| 2230 | case AF_INET2: |
| 2231 | src.sa.sa_len = sizeof(struct sockaddr_in); |
| 2232 | src.sa.sa_family = AF_INET2; |
| 2233 | src.sin.sin_addr = mtod(m, struct ip *)((struct ip *)((m)->m_hdr.mh_data))->ip_src; |
| 2234 | dst.sa.sa_len = sizeof(struct sockaddr_in); |
| 2235 | dst.sa.sa_family = AF_INET2; |
| 2236 | dst.sin.sin_addr = mtod(m, struct ip *)((struct ip *)((m)->m_hdr.mh_data))->ip_dst; |
| 2237 | break; |
| 2238 | #ifdef INET61 |
| 2239 | case AF_INET624: |
| 2240 | src.sa.sa_len = sizeof(struct sockaddr_in6); |
| 2241 | src.sa.sa_family = AF_INET624; |
| 2242 | src.sin6.sin6_addr = mtod(m, struct ip6_hdr *)((struct ip6_hdr *)((m)->m_hdr.mh_data))->ip6_src; |
| 2243 | dst.sa.sa_len = sizeof(struct sockaddr_in6); |
| 2244 | dst.sa.sa_family = AF_INET624; |
| 2245 | dst.sin6.sin6_addr = mtod(m, struct ip6_hdr *)((struct ip6_hdr *)((m)->m_hdr.mh_data))->ip6_dst; |
| 2246 | break; |
| 2247 | #endif /* INET6 */ |
| 2248 | } |
| 2249 | |
| 2250 | tdb = gettdbbysrcdst(rtable_l2(rtableid),gettdbbysrcdst_dir((rtable_l2(rtableid)),(0),(&src),(& dst),(6),0) |
| 2251 | 0, &src, &dst, IPPROTO_TCP)gettdbbysrcdst_dir((rtable_l2(rtableid)),(0),(&src),(& dst),(6),0); |
| 2252 | |
| 2253 | /* |
| 2254 | * We don't have an SA for this peer, so we turn off |
| 2255 | * TF_SIGNATURE on the listen socket |
| 2256 | */ |
| 2257 | if (tdb == NULL((void *)0) && tp->t_state == TCPS_LISTEN1) |
| 2258 | tp->t_flags &= ~TF_SIGNATURE0x0400U; |
| 2259 | |
| 2260 | } |
| 2261 | |
| 2262 | if ((sigp ? TF_SIGNATURE0x0400U : 0) ^ (tp->t_flags & TF_SIGNATURE0x0400U)) { |
| 2263 | tcpstat_inc(tcps_rcvbadsig); |
| 2264 | goto bad; |
| 2265 | } |
| 2266 | |
| 2267 | if (sigp) { |
| 2268 | char sig[16]; |
| 2269 | |
| 2270 | if (tdb == NULL((void *)0)) { |
| 2271 | tcpstat_inc(tcps_rcvbadsig); |
| 2272 | goto bad; |
| 2273 | } |
| 2274 | |
| 2275 | if (tcp_signature(tdb, tp->pf, m, th, iphlen, 1, sig) < 0) |
| 2276 | goto bad; |
| 2277 | |
| 2278 | if (timingsafe_bcmp(sig, sigp, 16)) { |
| 2279 | tcpstat_inc(tcps_rcvbadsig); |
| 2280 | goto bad; |
| 2281 | } |
| 2282 | |
| 2283 | tcpstat_inc(tcps_rcvgoodsig); |
| 2284 | } |
| 2285 | |
| 2286 | tdb_unref(tdb); |
| 2287 | #endif /* TCP_SIGNATURE */ |
| 2288 | |
| 2289 | return (0); |
| 2290 | |
| 2291 | #ifdef TCP_SIGNATURE1 |
| 2292 | bad: |
| 2293 | tdb_unref(tdb); |
| 2294 | #endif /* TCP_SIGNATURE */ |
| 2295 | return (-1); |
| 2296 | } |
| 2297 | |
| 2298 | u_long |
| 2299 | tcp_seq_subtract(u_long a, u_long b) |
| 2300 | { |
| 2301 | return ((long)(a - b)); |
| 2302 | } |
| 2303 | |
| 2304 | /* |
| 2305 | * This function is called upon receipt of new valid data (while not in header |
| 2306 | * prediction mode), and it updates the ordered list of sacks. |
| 2307 | */ |
| 2308 | void |
| 2309 | tcp_update_sack_list(struct tcpcb *tp, tcp_seq rcv_laststart, |
| 2310 | tcp_seq rcv_lastend) |
| 2311 | { |
| 2312 | /* |
| 2313 | * First reported block MUST be the most recent one. Subsequent |
| 2314 | * blocks SHOULD be in the order in which they arrived at the |
| 2315 | * receiver. These two conditions make the implementation fully |
| 2316 | * compliant with RFC 2018. |
| 2317 | */ |
| 2318 | int i, j = 0, count = 0, lastpos = -1; |
| 2319 | struct sackblk sack, firstsack, temp[MAX_SACK_BLKS6]; |
| 2320 | |
| 2321 | /* First clean up current list of sacks */ |
| 2322 | for (i = 0; i < tp->rcv_numsacks; i++) { |
| 2323 | sack = tp->sackblks[i]; |
| 2324 | if (sack.start == 0 && sack.end == 0) { |
| 2325 | count++; /* count = number of blocks to be discarded */ |
| 2326 | continue; |
| 2327 | } |
| 2328 | if (SEQ_LEQ(sack.end, tp->rcv_nxt)((int)((sack.end)-(tp->rcv_nxt)) <= 0)) { |
| 2329 | tp->sackblks[i].start = tp->sackblks[i].end = 0; |
| 2330 | count++; |
| 2331 | } else { |
| 2332 | temp[j].start = tp->sackblks[i].start; |
| 2333 | temp[j++].end = tp->sackblks[i].end; |
| 2334 | } |
| 2335 | } |
| 2336 | tp->rcv_numsacks -= count; |
| 2337 | if (tp->rcv_numsacks == 0) { /* no sack blocks currently (fast path) */ |
| 2338 | tcp_clean_sackreport(tp); |
| 2339 | if (SEQ_LT(tp->rcv_nxt, rcv_laststart)((int)((tp->rcv_nxt)-(rcv_laststart)) < 0)) { |
| 2340 | /* ==> need first sack block */ |
| 2341 | tp->sackblks[0].start = rcv_laststart; |
| 2342 | tp->sackblks[0].end = rcv_lastend; |
| 2343 | tp->rcv_numsacks = 1; |
| 2344 | } |
| 2345 | return; |
| 2346 | } |
| 2347 | /* Otherwise, sack blocks are already present. */ |
| 2348 | for (i = 0; i < tp->rcv_numsacks; i++) |
| 2349 | tp->sackblks[i] = temp[i]; /* first copy back sack list */ |
| 2350 | if (SEQ_GEQ(tp->rcv_nxt, rcv_lastend)((int)((tp->rcv_nxt)-(rcv_lastend)) >= 0)) |
| 2351 | return; /* sack list remains unchanged */ |
| 2352 | /* |
| 2353 | * From here, segment just received should be (part of) the 1st sack. |
| 2354 | * Go through list, possibly coalescing sack block entries. |
| 2355 | */ |
| 2356 | firstsack.start = rcv_laststart; |
| 2357 | firstsack.end = rcv_lastend; |
| 2358 | for (i = 0; i < tp->rcv_numsacks; i++) { |
| 2359 | sack = tp->sackblks[i]; |
| 2360 | if (SEQ_LT(sack.end, firstsack.start)((int)((sack.end)-(firstsack.start)) < 0) || |
| 2361 | SEQ_GT(sack.start, firstsack.end)((int)((sack.start)-(firstsack.end)) > 0)) |
| 2362 | continue; /* no overlap */ |
| 2363 | if (sack.start == firstsack.start && sack.end == firstsack.end){ |
| 2364 | /* |
| 2365 | * identical block; delete it here since we will |
| 2366 | * move it to the front of the list. |
| 2367 | */ |
| 2368 | tp->sackblks[i].start = tp->sackblks[i].end = 0; |
| 2369 | lastpos = i; /* last posn with a zero entry */ |
| 2370 | continue; |
| 2371 | } |
| 2372 | if (SEQ_LEQ(sack.start, firstsack.start)((int)((sack.start)-(firstsack.start)) <= 0)) |
| 2373 | firstsack.start = sack.start; /* merge blocks */ |
| 2374 | if (SEQ_GEQ(sack.end, firstsack.end)((int)((sack.end)-(firstsack.end)) >= 0)) |
| 2375 | firstsack.end = sack.end; /* merge blocks */ |
| 2376 | tp->sackblks[i].start = tp->sackblks[i].end = 0; |
| 2377 | lastpos = i; /* last posn with a zero entry */ |
| 2378 | } |
| 2379 | if (lastpos != -1) { /* at least one merge */ |
| 2380 | for (i = 0, j = 1; i < tp->rcv_numsacks; i++) { |
| 2381 | sack = tp->sackblks[i]; |
| 2382 | if (sack.start == 0 && sack.end == 0) |
| 2383 | continue; |
| 2384 | temp[j++] = sack; |
| 2385 | } |
| 2386 | tp->rcv_numsacks = j; /* including first blk (added later) */ |
| 2387 | for (i = 1; i < tp->rcv_numsacks; i++) /* now copy back */ |
| 2388 | tp->sackblks[i] = temp[i]; |
| 2389 | } else { /* no merges -- shift sacks by 1 */ |
| 2390 | if (tp->rcv_numsacks < MAX_SACK_BLKS6) |
| 2391 | tp->rcv_numsacks++; |
| 2392 | for (i = tp->rcv_numsacks-1; i > 0; i--) |
| 2393 | tp->sackblks[i] = tp->sackblks[i-1]; |
| 2394 | } |
| 2395 | tp->sackblks[0] = firstsack; |
| 2396 | return; |
| 2397 | } |
| 2398 | |
| 2399 | /* |
| 2400 | * Process the TCP SACK option. tp->snd_holes is an ordered list |
| 2401 | * of holes (oldest to newest, in terms of the sequence space). |
| 2402 | */ |
| 2403 | void |
| 2404 | tcp_sack_option(struct tcpcb *tp, struct tcphdr *th, u_char *cp, int optlen) |
| 2405 | { |
| 2406 | int tmp_olen; |
| 2407 | u_char *tmp_cp; |
| 2408 | struct sackhole *cur, *p, *temp; |
| 2409 | |
| 2410 | if (!tp->sack_enable) |
| 2411 | return; |
| 2412 | /* SACK without ACK doesn't make sense. */ |
| 2413 | if ((th->th_flags & TH_ACK0x10) == 0) |
| 2414 | return; |
| 2415 | /* Make sure the ACK on this segment is in [snd_una, snd_max]. */ |
| 2416 | if (SEQ_LT(th->th_ack, tp->snd_una)((int)((th->th_ack)-(tp->snd_una)) < 0) || |
| 2417 | SEQ_GT(th->th_ack, tp->snd_max)((int)((th->th_ack)-(tp->snd_max)) > 0)) |
| 2418 | return; |
| 2419 | /* Note: TCPOLEN_SACK must be 2*sizeof(tcp_seq) */ |
| 2420 | if (optlen <= 2 || (optlen - 2) % TCPOLEN_SACK8 != 0) |
| 2421 | return; |
| 2422 | /* Note: TCPOLEN_SACK must be 2*sizeof(tcp_seq) */ |
| 2423 | tmp_cp = cp + 2; |
| 2424 | tmp_olen = optlen - 2; |
| 2425 | tcpstat_inc(tcps_sack_rcv_opts); |
| 2426 | if (tp->snd_numholes < 0) |
| 2427 | tp->snd_numholes = 0; |
| 2428 | if (tp->t_maxseg == 0) |
| 2429 | panic("tcp_sack_option"); /* Should never happen */ |
| 2430 | while (tmp_olen > 0) { |
| 2431 | struct sackblk sack; |
| 2432 | |
| 2433 | memcpy(&sack.start, tmp_cp, sizeof(tcp_seq))__builtin_memcpy((&sack.start), (tmp_cp), (sizeof(tcp_seq ))); |
| 2434 | sack.start = ntohl(sack.start)(__uint32_t)(__builtin_constant_p(sack.start) ? (__uint32_t)( ((__uint32_t)(sack.start) & 0xff) << 24 | ((__uint32_t )(sack.start) & 0xff00) << 8 | ((__uint32_t)(sack.start ) & 0xff0000) >> 8 | ((__uint32_t)(sack.start) & 0xff000000) >> 24) : __swap32md(sack.start)); |
| 2435 | memcpy(&sack.end, tmp_cp + sizeof(tcp_seq), sizeof(tcp_seq))__builtin_memcpy((&sack.end), (tmp_cp + sizeof(tcp_seq)), (sizeof(tcp_seq))); |
| 2436 | sack.end = ntohl(sack.end)(__uint32_t)(__builtin_constant_p(sack.end) ? (__uint32_t)((( __uint32_t)(sack.end) & 0xff) << 24 | ((__uint32_t) (sack.end) & 0xff00) << 8 | ((__uint32_t)(sack.end) & 0xff0000) >> 8 | ((__uint32_t)(sack.end) & 0xff000000 ) >> 24) : __swap32md(sack.end)); |
| 2437 | tmp_olen -= TCPOLEN_SACK8; |
| 2438 | tmp_cp += TCPOLEN_SACK8; |
| 2439 | if (SEQ_LEQ(sack.end, sack.start)((int)((sack.end)-(sack.start)) <= 0)) |
| 2440 | continue; /* bad SACK fields */ |
| 2441 | if (SEQ_LEQ(sack.end, tp->snd_una)((int)((sack.end)-(tp->snd_una)) <= 0)) |
| 2442 | continue; /* old block */ |
| 2443 | if (SEQ_GT(th->th_ack, tp->snd_una)((int)((th->th_ack)-(tp->snd_una)) > 0)) { |
| 2444 | if (SEQ_LT(sack.start, th->th_ack)((int)((sack.start)-(th->th_ack)) < 0)) |
| 2445 | continue; |
| 2446 | } |
| 2447 | if (SEQ_GT(sack.end, tp->snd_max)((int)((sack.end)-(tp->snd_max)) > 0)) |
| 2448 | continue; |
| 2449 | if (tp->snd_holes == NULL((void *)0)) { /* first hole */ |
| 2450 | tp->snd_holes = (struct sackhole *) |
| 2451 | pool_get(&sackhl_pool, PR_NOWAIT0x0002); |
| 2452 | if (tp->snd_holes == NULL((void *)0)) { |
| 2453 | /* ENOBUFS, so ignore SACKed block for now */ |
| 2454 | goto dropped; |
| 2455 | } |
| 2456 | cur = tp->snd_holes; |
| 2457 | cur->start = th->th_ack; |
| 2458 | cur->end = sack.start; |
| 2459 | cur->rxmit = cur->start; |
| 2460 | cur->next = NULL((void *)0); |
| 2461 | tp->snd_numholes = 1; |
| 2462 | tp->rcv_lastsack = sack.end; |
| 2463 | /* |
| 2464 | * dups is at least one. If more data has been |
| 2465 | * SACKed, it can be greater than one. |
| 2466 | */ |
| 2467 | cur->dups = min(tcprexmtthresh, |
| 2468 | ((sack.end - cur->end)/tp->t_maxseg)); |
| 2469 | if (cur->dups < 1) |
| 2470 | cur->dups = 1; |
| 2471 | continue; /* with next sack block */ |
| 2472 | } |
| 2473 | /* Go thru list of holes: p = previous, cur = current */ |
| 2474 | p = cur = tp->snd_holes; |
| 2475 | while (cur) { |
| 2476 | if (SEQ_LEQ(sack.end, cur->start)((int)((sack.end)-(cur->start)) <= 0)) |
| 2477 | /* SACKs data before the current hole */ |
| 2478 | break; /* no use going through more holes */ |
| 2479 | if (SEQ_GEQ(sack.start, cur->end)((int)((sack.start)-(cur->end)) >= 0)) { |
| 2480 | /* SACKs data beyond the current hole */ |
| 2481 | cur->dups++; |
| 2482 | if (((sack.end - cur->end)/tp->t_maxseg) >= |
| 2483 | tcprexmtthresh) |
| 2484 | cur->dups = tcprexmtthresh; |
| 2485 | p = cur; |
| 2486 | cur = cur->next; |
| 2487 | continue; |
| 2488 | } |
| 2489 | if (SEQ_LEQ(sack.start, cur->start)((int)((sack.start)-(cur->start)) <= 0)) { |
| 2490 | /* Data acks at least the beginning of hole */ |
| 2491 | if (SEQ_GEQ(sack.end, cur->end)((int)((sack.end)-(cur->end)) >= 0)) { |
| 2492 | /* Acks entire hole, so delete hole */ |
| 2493 | if (p != cur) { |
| 2494 | p->next = cur->next; |
| 2495 | pool_put(&sackhl_pool, cur); |
| 2496 | cur = p->next; |
| 2497 | } else { |
| 2498 | cur = cur->next; |
| 2499 | pool_put(&sackhl_pool, p); |
| 2500 | p = cur; |
| 2501 | tp->snd_holes = p; |
| 2502 | } |
| 2503 | tp->snd_numholes--; |
| 2504 | continue; |
| 2505 | } |
| 2506 | /* otherwise, move start of hole forward */ |
| 2507 | cur->start = sack.end; |
| 2508 | cur->rxmit = SEQ_MAX(cur->rxmit, cur->start)(((int)((cur->rxmit)-(cur->start)) > 0) ? (cur->rxmit ) : (cur->start)); |
| 2509 | p = cur; |
| 2510 | cur = cur->next; |
| 2511 | continue; |
| 2512 | } |
| 2513 | /* move end of hole backward */ |
| 2514 | if (SEQ_GEQ(sack.end, cur->end)((int)((sack.end)-(cur->end)) >= 0)) { |
| 2515 | cur->end = sack.start; |
| 2516 | cur->rxmit = SEQ_MIN(cur->rxmit, cur->end)(((int)((cur->rxmit)-(cur->end)) < 0) ? (cur->rxmit ) : (cur->end)); |
| 2517 | cur->dups++; |
| 2518 | if (((sack.end - cur->end)/tp->t_maxseg) >= |
| 2519 | tcprexmtthresh) |
| 2520 | cur->dups = tcprexmtthresh; |
| 2521 | p = cur; |
| 2522 | cur = cur->next; |
| 2523 | continue; |
| 2524 | } |
| 2525 | if (SEQ_LT(cur->start, sack.start)((int)((cur->start)-(sack.start)) < 0) && |
| 2526 | SEQ_GT(cur->end, sack.end)((int)((cur->end)-(sack.end)) > 0)) { |
| 2527 | /* |
| 2528 | * ACKs some data in middle of a hole; need to |
| 2529 | * split current hole |
| 2530 | */ |
| 2531 | if (tp->snd_numholes >= TCP_SACKHOLE_LIMIT128) |
| 2532 | goto dropped; |
| 2533 | temp = (struct sackhole *) |
| 2534 | pool_get(&sackhl_pool, PR_NOWAIT0x0002); |
| 2535 | if (temp == NULL((void *)0)) |
| 2536 | goto dropped; /* ENOBUFS */ |
| 2537 | temp->next = cur->next; |
| 2538 | temp->start = sack.end; |
| 2539 | temp->end = cur->end; |
| 2540 | temp->dups = cur->dups; |
| 2541 | temp->rxmit = SEQ_MAX(cur->rxmit, temp->start)(((int)((cur->rxmit)-(temp->start)) > 0) ? (cur-> rxmit) : (temp->start)); |
| 2542 | cur->end = sack.start; |
| 2543 | cur->rxmit = SEQ_MIN(cur->rxmit, cur->end)(((int)((cur->rxmit)-(cur->end)) < 0) ? (cur->rxmit ) : (cur->end)); |
| 2544 | cur->dups++; |
| 2545 | if (((sack.end - cur->end)/tp->t_maxseg) >= |
| 2546 | tcprexmtthresh) |
| 2547 | cur->dups = tcprexmtthresh; |
| 2548 | cur->next = temp; |
| 2549 | p = temp; |
| 2550 | cur = p->next; |
| 2551 | tp->snd_numholes++; |
| 2552 | } |
| 2553 | } |
| 2554 | /* At this point, p points to the last hole on the list */ |
| 2555 | if (SEQ_LT(tp->rcv_lastsack, sack.start)((int)((tp->rcv_lastsack)-(sack.start)) < 0)) { |
| 2556 | /* |
| 2557 | * Need to append new hole at end. |
| 2558 | * Last hole is p (and it's not NULL). |
| 2559 | */ |
| 2560 | if (tp->snd_numholes >= TCP_SACKHOLE_LIMIT128) |
| 2561 | goto dropped; |
| 2562 | temp = (struct sackhole *) |
| 2563 | pool_get(&sackhl_pool, PR_NOWAIT0x0002); |
| 2564 | if (temp == NULL((void *)0)) |
| 2565 | goto dropped; /* ENOBUFS */ |
| 2566 | temp->start = tp->rcv_lastsack; |
| 2567 | temp->end = sack.start; |
| 2568 | temp->dups = min(tcprexmtthresh, |
| 2569 | ((sack.end - sack.start)/tp->t_maxseg)); |
| 2570 | if (temp->dups < 1) |
| 2571 | temp->dups = 1; |
| 2572 | temp->rxmit = temp->start; |
| 2573 | temp->next = 0; |
| 2574 | p->next = temp; |
| 2575 | tp->rcv_lastsack = sack.end; |
| 2576 | tp->snd_numholes++; |
| 2577 | } |
| 2578 | } |
| 2579 | return; |
| 2580 | dropped: |
| 2581 | tcpstat_inc(tcps_sack_drop_opts); |
| 2582 | } |
| 2583 | |
| 2584 | /* |
| 2585 | * Delete stale (i.e, cumulatively ack'd) holes. Hole is deleted only if |
| 2586 | * it is completely acked; otherwise, tcp_sack_option(), called from |
| 2587 | * tcp_dooptions(), will fix up the hole. |
| 2588 | */ |
| 2589 | void |
| 2590 | tcp_del_sackholes(struct tcpcb *tp, struct tcphdr *th) |
| 2591 | { |
| 2592 | if (tp->sack_enable && tp->t_state != TCPS_LISTEN1) { |
| 2593 | /* max because this could be an older ack just arrived */ |
| 2594 | tcp_seq lastack = SEQ_GT(th->th_ack, tp->snd_una)((int)((th->th_ack)-(tp->snd_una)) > 0) ? |
| 2595 | th->th_ack : tp->snd_una; |
| 2596 | struct sackhole *cur = tp->snd_holes; |
| 2597 | struct sackhole *prev; |
| 2598 | while (cur) |
| 2599 | if (SEQ_LEQ(cur->end, lastack)((int)((cur->end)-(lastack)) <= 0)) { |
| 2600 | prev = cur; |
| 2601 | cur = cur->next; |
| 2602 | pool_put(&sackhl_pool, prev); |
| 2603 | tp->snd_numholes--; |
| 2604 | } else if (SEQ_LT(cur->start, lastack)((int)((cur->start)-(lastack)) < 0)) { |
| 2605 | cur->start = lastack; |
| 2606 | if (SEQ_LT(cur->rxmit, cur->start)((int)((cur->rxmit)-(cur->start)) < 0)) |
| 2607 | cur->rxmit = cur->start; |
| 2608 | break; |
| 2609 | } else |
| 2610 | break; |
| 2611 | tp->snd_holes = cur; |
| 2612 | } |
| 2613 | } |
| 2614 | |
| 2615 | /* |
| 2616 | * Delete all receiver-side SACK information. |
| 2617 | */ |
| 2618 | void |
| 2619 | tcp_clean_sackreport(struct tcpcb *tp) |
| 2620 | { |
| 2621 | int i; |
| 2622 | |
| 2623 | tp->rcv_numsacks = 0; |
| 2624 | for (i = 0; i < MAX_SACK_BLKS6; i++) |
| 2625 | tp->sackblks[i].start = tp->sackblks[i].end=0; |
| 2626 | |
| 2627 | } |
| 2628 | |
| 2629 | /* |
| 2630 | * Partial ack handling within a sack recovery episode. When a partial ack |
| 2631 | * arrives, turn off retransmission timer, deflate the window, do not clear |
| 2632 | * tp->t_dupacks. |
| 2633 | */ |
| 2634 | void |
| 2635 | tcp_sack_partialack(struct tcpcb *tp, struct tcphdr *th) |
| 2636 | { |
| 2637 | /* Turn off retx. timer (will start again next segment) */ |
| 2638 | TCP_TIMER_DISARM(tp, TCPT_REXMT)do { (((tp)->t_flags) &= ~(0x04000000U << (0))); timeout_del(&(tp)->t_timer[(0)]); } while (0); |
| 2639 | tp->t_rtttime = 0; |
| 2640 | /* |
| 2641 | * Partial window deflation. This statement relies on the |
| 2642 | * fact that tp->snd_una has not been updated yet. |
| 2643 | */ |
| 2644 | if (tp->snd_cwnd > (th->th_ack - tp->snd_una)) { |
| 2645 | tp->snd_cwnd -= th->th_ack - tp->snd_una; |
| 2646 | tp->snd_cwnd += tp->t_maxseg; |
| 2647 | } else |
| 2648 | tp->snd_cwnd = tp->t_maxseg; |
| 2649 | tp->snd_cwnd += tp->t_maxseg; |
| 2650 | tp->t_flags |= TF_NEEDOUTPUT0x00800000U; |
| 2651 | } |
| 2652 | |
| 2653 | /* |
| 2654 | * Pull out of band byte out of a segment so |
| 2655 | * it doesn't appear in the user's data queue. |
| 2656 | * It is still reflected in the segment length for |
| 2657 | * sequencing purposes. |
| 2658 | */ |
| 2659 | void |
| 2660 | tcp_pulloutofband(struct socket *so, u_int urgent, struct mbuf *m, int off) |
| 2661 | { |
| 2662 | int cnt = off + urgent - 1; |
| 2663 | |
| 2664 | while (cnt >= 0) { |
| 2665 | if (m->m_lenm_hdr.mh_len > cnt) { |
| 2666 | char *cp = mtod(m, caddr_t)((caddr_t)((m)->m_hdr.mh_data)) + cnt; |
| 2667 | struct tcpcb *tp = sototcpcb(so)(((struct tcpcb *)(((struct inpcb *)(so)->so_pcb))->inp_ppcb )); |
| 2668 | |
| 2669 | tp->t_iobc = *cp; |
| 2670 | tp->t_oobflags |= TCPOOB_HAVEDATA0x01; |
| 2671 | memmove(cp, cp + 1, m->m_len - cnt - 1)__builtin_memmove((cp), (cp + 1), (m->m_hdr.mh_len - cnt - 1)); |
| 2672 | m->m_lenm_hdr.mh_len--; |
| 2673 | return; |
| 2674 | } |
| 2675 | cnt -= m->m_lenm_hdr.mh_len; |
| 2676 | m = m->m_nextm_hdr.mh_next; |
| 2677 | if (m == NULL((void *)0)) |
| 2678 | break; |
| 2679 | } |
| 2680 | panic("tcp_pulloutofband"); |
| 2681 | } |
| 2682 | |
| 2683 | /* |
| 2684 | * Collect new round-trip time estimate |
| 2685 | * and update averages and current timeout. |
| 2686 | */ |
| 2687 | void |
| 2688 | tcp_xmit_timer(struct tcpcb *tp, int32_t rtt) |
| 2689 | { |
| 2690 | int delta, rttmin; |
| 2691 | |
| 2692 | if (rtt < 0) |
| 2693 | rtt = 0; |
| 2694 | else if (rtt > TCP_RTT_MAX(1<<18)) |
| 2695 | rtt = TCP_RTT_MAX(1<<18); |
| 2696 | |
| 2697 | tcpstat_inc(tcps_rttupdated); |
| 2698 | if (tp->t_srtt != 0) { |
| 2699 | /* |
| 2700 | * delta is fixed point with 2 (TCP_RTT_BASE_SHIFT) bits |
| 2701 | * after the binary point (scaled by 4), whereas |
| 2702 | * srtt is stored as fixed point with 5 bits after the |
| 2703 | * binary point (i.e., scaled by 32). The following magic |
| 2704 | * is equivalent to the smoothing algorithm in rfc793 with |
| 2705 | * an alpha of .875 (srtt = rtt/8 + srtt*7/8 in fixed |
| 2706 | * point). |
| 2707 | */ |
| 2708 | delta = (rtt << TCP_RTT_BASE_SHIFT2) - |
| 2709 | (tp->t_srtt >> TCP_RTT_SHIFT3); |
| 2710 | if ((tp->t_srtt += delta) <= 0) |
| 2711 | tp->t_srtt = 1 << TCP_RTT_BASE_SHIFT2; |
| 2712 | /* |
| 2713 | * We accumulate a smoothed rtt variance (actually, a |
| 2714 | * smoothed mean difference), then set the retransmit |
| 2715 | * timer to smoothed rtt + 4 times the smoothed variance. |
| 2716 | * rttvar is stored as fixed point with 4 bits after the |
| 2717 | * binary point (scaled by 16). The following is |
| 2718 | * equivalent to rfc793 smoothing with an alpha of .75 |
| 2719 | * (rttvar = rttvar*3/4 + |delta| / 4). This replaces |
| 2720 | * rfc793's wired-in beta. |
| 2721 | */ |
| 2722 | if (delta < 0) |
| 2723 | delta = -delta; |
| 2724 | delta -= (tp->t_rttvar >> TCP_RTTVAR_SHIFT2); |
| 2725 | if ((tp->t_rttvar += delta) <= 0) |
| 2726 | tp->t_rttvar = 1 << TCP_RTT_BASE_SHIFT2; |
| 2727 | } else { |
| 2728 | /* |
| 2729 | * No rtt measurement yet - use the unsmoothed rtt. |
| 2730 | * Set the variance to half the rtt (so our first |
| 2731 | * retransmit happens at 3*rtt). |
| 2732 | */ |
| 2733 | tp->t_srtt = (rtt + 1) << (TCP_RTT_SHIFT3 + TCP_RTT_BASE_SHIFT2); |
| 2734 | tp->t_rttvar = (rtt + 1) << |
| 2735 | (TCP_RTTVAR_SHIFT2 + TCP_RTT_BASE_SHIFT2 - 1); |
| 2736 | } |
| 2737 | tp->t_rtttime = 0; |
| 2738 | tp->t_rxtshift = 0; |
| 2739 | |
| 2740 | /* |
| 2741 | * the retransmit should happen at rtt + 4 * rttvar. |
| 2742 | * Because of the way we do the smoothing, srtt and rttvar |
| 2743 | * will each average +1/2 tick of bias. When we compute |
| 2744 | * the retransmit timer, we want 1/2 tick of rounding and |
| 2745 | * 1 extra tick because of +-1/2 tick uncertainty in the |
| 2746 | * firing of the timer. The bias will give us exactly the |
| 2747 | * 1.5 tick we need. But, because the bias is |
| 2748 | * statistical, we have to test that we don't drop below |
| 2749 | * the minimum feasible timer (which is 2 ticks). |
| 2750 | */ |
| 2751 | rttmin = min(max(tp->t_rttmin, rtt + 2 * (TCP_TIME(1)((1) * 1000) / hz)), |
| 2752 | TCPTV_REXMTMAX((64) * 1000)); |
| 2753 | TCPT_RANGESET(tp->t_rxtcur, TCP_REXMTVAL(tp), rttmin, TCPTV_REXMTMAX)do { (tp->t_rxtcur) = (((((tp)->t_srtt >> 3) + (tp )->t_rttvar) >> 2)); if ((tp->t_rxtcur) < (rttmin )) (tp->t_rxtcur) = (rttmin); else if ((tp->t_rxtcur) > (((64) * 1000))) (tp->t_rxtcur) = (((64) * 1000)); } while ( 0); |
| 2754 | |
| 2755 | /* |
| 2756 | * We received an ack for a packet that wasn't retransmitted; |
| 2757 | * it is probably safe to discard any error indications we've |
| 2758 | * received recently. This isn't quite right, but close enough |
| 2759 | * for now (a route might have failed after we sent a segment, |
| 2760 | * and the return path might not be symmetrical). |
| 2761 | */ |
| 2762 | tp->t_softerror = 0; |
| 2763 | } |
| 2764 | |
| 2765 | /* |
| 2766 | * Determine a reasonable value for maxseg size. |
| 2767 | * If the route is known, check route for mtu. |
| 2768 | * If none, use an mss that can be handled on the outgoing |
| 2769 | * interface without forcing IP to fragment; if bigger than |
| 2770 | * an mbuf cluster (MCLBYTES), round down to nearest multiple of MCLBYTES |
| 2771 | * to utilize large mbufs. If no route is found, route has no mtu, |
| 2772 | * or the destination isn't local, use a default, hopefully conservative |
| 2773 | * size (usually 512 or the default IP max size, but no more than the mtu |
| 2774 | * of the interface), as we can't discover anything about intervening |
| 2775 | * gateways or networks. We also initialize the congestion/slow start |
| 2776 | * window to be a single segment if the destination isn't local. |
| 2777 | * While looking at the routing entry, we also initialize other path-dependent |
| 2778 | * parameters from pre-set or cached values in the routing entry. |
| 2779 | * |
| 2780 | * Also take into account the space needed for options that we |
| 2781 | * send regularly. Make maxseg shorter by that amount to assure |
| 2782 | * that we can send maxseg amount of data even when the options |
| 2783 | * are present. Store the upper limit of the length of options plus |
| 2784 | * data in maxopd. |
| 2785 | * |
| 2786 | * NOTE: offer == -1 indicates that the maxseg size changed due to |
| 2787 | * Path MTU discovery. |
| 2788 | */ |
| 2789 | int |
| 2790 | tcp_mss(struct tcpcb *tp, int offer) |
| 2791 | { |
| 2792 | struct rtentry *rt; |
| 2793 | struct ifnet *ifp = NULL((void *)0); |
| 2794 | int mss, mssopt; |
| 2795 | int iphlen; |
| 2796 | struct inpcb *inp; |
| 2797 | |
| 2798 | inp = tp->t_inpcb; |
| 2799 | |
| 2800 | mssopt = mss = tcp_mssdflt; |
| 2801 | |
| 2802 | rt = in_pcbrtentry(inp); |
| 2803 | |
| 2804 | if (rt == NULL((void *)0)) |
| 2805 | goto out; |
| 2806 | |
| 2807 | ifp = if_get(rt->rt_ifidx); |
| 2808 | if (ifp == NULL((void *)0)) |
| 2809 | goto out; |
| 2810 | |
| 2811 | switch (tp->pf) { |
| 2812 | #ifdef INET61 |
| 2813 | case AF_INET624: |
| 2814 | iphlen = sizeof(struct ip6_hdr); |
| 2815 | break; |
| 2816 | #endif |
| 2817 | case AF_INET2: |
| 2818 | iphlen = sizeof(struct ip); |
| 2819 | break; |
| 2820 | default: |
| 2821 | /* the family does not support path MTU discovery */ |
| 2822 | goto out; |
| 2823 | } |
| 2824 | |
| 2825 | /* |
| 2826 | * if there's an mtu associated with the route and we support |
| 2827 | * path MTU discovery for the underlying protocol family, use it. |
| 2828 | */ |
| 2829 | if (rt->rt_mturt_rmx.rmx_mtu) { |
| 2830 | /* |
| 2831 | * One may wish to lower MSS to take into account options, |
| 2832 | * especially security-related options. |
| 2833 | */ |
| 2834 | if (tp->pf == AF_INET624 && rt->rt_mturt_rmx.rmx_mtu < IPV6_MMTU1280) { |
| 2835 | /* |
| 2836 | * RFC2460 section 5, last paragraph: if path MTU is |
| 2837 | * smaller than 1280, use 1280 as packet size and |
| 2838 | * attach fragment header. |
| 2839 | */ |
| 2840 | mss = IPV6_MMTU1280 - iphlen - sizeof(struct ip6_frag) - |
| 2841 | sizeof(struct tcphdr); |
| 2842 | } else { |
| 2843 | mss = rt->rt_mturt_rmx.rmx_mtu - iphlen - |
| 2844 | sizeof(struct tcphdr); |
| 2845 | } |
| 2846 | } else if (ifp->if_flags & IFF_LOOPBACK0x8) { |
| 2847 | mss = ifp->if_mtuif_data.ifi_mtu - iphlen - sizeof(struct tcphdr); |
| 2848 | } else if (tp->pf == AF_INET2) { |
| 2849 | if (ip_mtudisc) |
| 2850 | mss = ifp->if_mtuif_data.ifi_mtu - iphlen - sizeof(struct tcphdr); |
| 2851 | } |
| 2852 | #ifdef INET61 |
| 2853 | else if (tp->pf == AF_INET624) { |
| 2854 | /* |
| 2855 | * for IPv6, path MTU discovery is always turned on, |
| 2856 | * or the node must use packet size <= 1280. |
| 2857 | */ |
| 2858 | mss = ifp->if_mtuif_data.ifi_mtu - iphlen - sizeof(struct tcphdr); |
| 2859 | } |
| 2860 | #endif /* INET6 */ |
| 2861 | |
| 2862 | /* Calculate the value that we offer in TCPOPT_MAXSEG */ |
| 2863 | if (offer != -1) { |
| 2864 | mssopt = ifp->if_mtuif_data.ifi_mtu - iphlen - sizeof(struct tcphdr); |
| 2865 | mssopt = max(tcp_mssdflt, mssopt); |
| 2866 | } |
| 2867 | out: |
| 2868 | if_put(ifp); |
| 2869 | /* |
| 2870 | * The current mss, t_maxseg, is initialized to the default value. |
| 2871 | * If we compute a smaller value, reduce the current mss. |
| 2872 | * If we compute a larger value, return it for use in sending |
| 2873 | * a max seg size option, but don't store it for use |
| 2874 | * unless we received an offer at least that large from peer. |
| 2875 | * |
| 2876 | * However, do not accept offers lower than the minimum of |
| 2877 | * the interface MTU and 216. |
| 2878 | */ |
| 2879 | if (offer > 0) |
| 2880 | tp->t_peermss = offer; |
| 2881 | if (tp->t_peermss) |
| 2882 | mss = min(mss, max(tp->t_peermss, 216)); |
| 2883 | |
| 2884 | /* sanity - at least max opt. space */ |
| 2885 | mss = max(mss, 64); |
| 2886 | |
| 2887 | /* |
| 2888 | * maxopd stores the maximum length of data AND options |
| 2889 | * in a segment; maxseg is the amount of data in a normal |
| 2890 | * segment. We need to store this value (maxopd) apart |
| 2891 | * from maxseg, because now every segment carries options |
| 2892 | * and thus we normally have somewhat less data in segments. |
| 2893 | */ |
| 2894 | tp->t_maxopd = mss; |
| 2895 | |
| 2896 | if ((tp->t_flags & (TF_REQ_TSTMP0x0080U|TF_NOOPT0x0008U)) == TF_REQ_TSTMP0x0080U && |
| 2897 | (tp->t_flags & TF_RCVD_TSTMP0x0100U) == TF_RCVD_TSTMP0x0100U) |
| 2898 | mss -= TCPOLEN_TSTAMP_APPA(10 +2); |
| 2899 | #ifdef TCP_SIGNATURE1 |
| 2900 | if (tp->t_flags & TF_SIGNATURE0x0400U) |
| 2901 | mss -= TCPOLEN_SIGLEN(18 +2); |
| 2902 | #endif |
| 2903 | |
| 2904 | if (offer == -1) { |
| 2905 | /* mss changed due to Path MTU discovery */ |
| 2906 | tp->t_flags &= ~TF_PMTUD_PEND0x00400000U; |
| 2907 | tp->t_pmtud_mtu_sent = 0; |
| 2908 | tp->t_pmtud_mss_acked = 0; |
| 2909 | if (mss < tp->t_maxseg) { |
| 2910 | /* |
| 2911 | * Follow suggestion in RFC 2414 to reduce the |
| 2912 | * congestion window by the ratio of the old |
| 2913 | * segment size to the new segment size. |
| 2914 | */ |
| 2915 | tp->snd_cwnd = ulmax((tp->snd_cwnd / tp->t_maxseg) * |
| 2916 | mss, mss); |
| 2917 | } |
| 2918 | } else if (tcp_do_rfc3390 == 2) { |
| 2919 | /* increase initial window */ |
| 2920 | tp->snd_cwnd = ulmin(10 * mss, ulmax(2 * mss, 14600)); |
| 2921 | } else if (tcp_do_rfc3390) { |
| 2922 | /* increase initial window */ |
| 2923 | tp->snd_cwnd = ulmin(4 * mss, ulmax(2 * mss, 4380)); |
| 2924 | } else |
| 2925 | tp->snd_cwnd = mss; |
| 2926 | |
| 2927 | tp->t_maxseg = mss; |
| 2928 | |
| 2929 | return (offer != -1 ? mssopt : mss); |
| 2930 | } |
| 2931 | |
| 2932 | u_int |
| 2933 | tcp_hdrsz(struct tcpcb *tp) |
| 2934 | { |
| 2935 | u_int hlen; |
| 2936 | |
| 2937 | switch (tp->pf) { |
| 2938 | #ifdef INET61 |
| 2939 | case AF_INET624: |
| 2940 | hlen = sizeof(struct ip6_hdr); |
| 2941 | break; |
| 2942 | #endif |
| 2943 | case AF_INET2: |
| 2944 | hlen = sizeof(struct ip); |
| 2945 | break; |
| 2946 | default: |
| 2947 | hlen = 0; |
| 2948 | break; |
| 2949 | } |
| 2950 | hlen += sizeof(struct tcphdr); |
| 2951 | |
| 2952 | if ((tp->t_flags & (TF_REQ_TSTMP0x0080U|TF_NOOPT0x0008U)) == TF_REQ_TSTMP0x0080U && |
| 2953 | (tp->t_flags & TF_RCVD_TSTMP0x0100U) == TF_RCVD_TSTMP0x0100U) |
| 2954 | hlen += TCPOLEN_TSTAMP_APPA(10 +2); |
| 2955 | #ifdef TCP_SIGNATURE1 |
| 2956 | if (tp->t_flags & TF_SIGNATURE0x0400U) |
| 2957 | hlen += TCPOLEN_SIGLEN(18 +2); |
| 2958 | #endif |
| 2959 | return (hlen); |
| 2960 | } |
| 2961 | |
| 2962 | /* |
| 2963 | * Set connection variables based on the effective MSS. |
| 2964 | * We are passed the TCPCB for the actual connection. If we |
| 2965 | * are the server, we are called by the compressed state engine |
| 2966 | * when the 3-way handshake is complete. If we are the client, |
| 2967 | * we are called when we receive the SYN,ACK from the server. |
| 2968 | * |
| 2969 | * NOTE: The t_maxseg value must be initialized in the TCPCB |
| 2970 | * before this routine is called! |
| 2971 | */ |
| 2972 | void |
| 2973 | tcp_mss_update(struct tcpcb *tp) |
| 2974 | { |
| 2975 | int mss; |
| 2976 | u_long bufsize; |
| 2977 | struct rtentry *rt; |
| 2978 | struct socket *so; |
| 2979 | |
| 2980 | so = tp->t_inpcb->inp_socket; |
| 2981 | mss = tp->t_maxseg; |
| 2982 | |
| 2983 | rt = in_pcbrtentry(tp->t_inpcb); |
| 2984 | |
| 2985 | if (rt == NULL((void *)0)) |
| 2986 | return; |
| 2987 | |
| 2988 | bufsize = so->so_snd.sb_hiwat; |
| 2989 | if (bufsize < mss) { |
| 2990 | mss = bufsize; |
| 2991 | /* Update t_maxseg and t_maxopd */ |
| 2992 | tcp_mss(tp, mss); |
| 2993 | } else { |
| 2994 | bufsize = roundup(bufsize, mss)((((bufsize)+((mss)-1))/(mss))*(mss)); |
| 2995 | if (bufsize > sb_max) |
| 2996 | bufsize = sb_max; |
| 2997 | (void)sbreserve(so, &so->so_snd, bufsize); |
| 2998 | } |
| 2999 | |
| 3000 | bufsize = so->so_rcv.sb_hiwat; |
| 3001 | if (bufsize > mss) { |
| 3002 | bufsize = roundup(bufsize, mss)((((bufsize)+((mss)-1))/(mss))*(mss)); |
| 3003 | if (bufsize > sb_max) |
| 3004 | bufsize = sb_max; |
| 3005 | (void)sbreserve(so, &so->so_rcv, bufsize); |
| 3006 | } |
| 3007 | |
| 3008 | } |
| 3009 | |
| 3010 | /* |
| 3011 | * When a partial ack arrives, force the retransmission of the |
| 3012 | * next unacknowledged segment. Do not clear tp->t_dupacks. |
| 3013 | * By setting snd_nxt to ti_ack, this forces retransmission timer |
| 3014 | * to be started again. |
| 3015 | */ |
| 3016 | void |
| 3017 | tcp_newreno_partialack(struct tcpcb *tp, struct tcphdr *th) |
| 3018 | { |
| 3019 | /* |
| 3020 | * snd_una has not been updated and the socket send buffer |
| 3021 | * not yet drained of the acked data, so we have to leave |
| 3022 | * snd_una as it was to get the correct data offset in |
| 3023 | * tcp_output(). |
| 3024 | */ |
| 3025 | tcp_seq onxt = tp->snd_nxt; |
| 3026 | u_long ocwnd = tp->snd_cwnd; |
| 3027 | |
| 3028 | TCP_TIMER_DISARM(tp, TCPT_REXMT)do { (((tp)->t_flags) &= ~(0x04000000U << (0))); timeout_del(&(tp)->t_timer[(0)]); } while (0); |
| 3029 | tp->t_rtttime = 0; |
| 3030 | tp->snd_nxt = th->th_ack; |
| 3031 | /* |
| 3032 | * Set snd_cwnd to one segment beyond acknowledged offset |
| 3033 | * (tp->snd_una not yet updated when this function is called) |
| 3034 | */ |
| 3035 | tp->snd_cwnd = tp->t_maxseg + (th->th_ack - tp->snd_una); |
| 3036 | (void)tcp_output(tp); |
| 3037 | tp->snd_cwnd = ocwnd; |
| 3038 | if (SEQ_GT(onxt, tp->snd_nxt)((int)((onxt)-(tp->snd_nxt)) > 0)) |
| 3039 | tp->snd_nxt = onxt; |
| 3040 | /* |
| 3041 | * Partial window deflation. Relies on fact that tp->snd_una |
| 3042 | * not updated yet. |
| 3043 | */ |
| 3044 | if (tp->snd_cwnd > th->th_ack - tp->snd_una) |
| 3045 | tp->snd_cwnd -= th->th_ack - tp->snd_una; |
| 3046 | else |
| 3047 | tp->snd_cwnd = 0; |
| 3048 | tp->snd_cwnd += tp->t_maxseg; |
| 3049 | } |
| 3050 | |
| 3051 | int |
| 3052 | tcp_mss_adv(struct mbuf *m, int af) |
| 3053 | { |
| 3054 | int mss = 0; |
| 3055 | int iphlen; |
| 3056 | struct ifnet *ifp = NULL((void *)0); |
| 3057 | |
| 3058 | if (m && (m->m_flagsm_hdr.mh_flags & M_PKTHDR0x0002)) |
| 3059 | ifp = if_get(m->m_pkthdrM_dat.MH.MH_pkthdr.ph_ifidx); |
| 3060 | |
| 3061 | switch (af) { |
| 3062 | case AF_INET2: |
| 3063 | if (ifp != NULL((void *)0)) |
| 3064 | mss = ifp->if_mtuif_data.ifi_mtu; |
| 3065 | iphlen = sizeof(struct ip); |
| 3066 | break; |
| 3067 | #ifdef INET61 |
| 3068 | case AF_INET624: |
| 3069 | if (ifp != NULL((void *)0)) |
| 3070 | mss = ifp->if_mtuif_data.ifi_mtu; |
| 3071 | iphlen = sizeof(struct ip6_hdr); |
| 3072 | break; |
| 3073 | #endif |
| 3074 | default: |
| 3075 | unhandled_af(af); |
| 3076 | } |
| 3077 | if_put(ifp); |
| 3078 | mss = mss - iphlen - sizeof(struct tcphdr); |
| 3079 | return (max(mss, tcp_mssdflt)); |
| 3080 | } |
| 3081 | |
| 3082 | /* |
| 3083 | * TCP compressed state engine. Currently used to hold compressed |
| 3084 | * state for SYN_RECEIVED. |
| 3085 | */ |
| 3086 | |
| 3087 | /* |
| 3088 | * Locks used to protect global data and struct members: |
| 3089 | * N net lock |
| 3090 | * S syn_cache_mtx tcp syn cache global mutex |
| 3091 | */ |
| 3092 | |
| 3093 | /* syn hash parameters */ |
| 3094 | int tcp_syn_hash_size = TCP_SYN_HASH_SIZE293; /* [N] size of hash table */ |
| 3095 | int tcp_syn_cache_limit = /* [N] global entry limit */ |
| 3096 | TCP_SYN_HASH_SIZE293 * TCP_SYN_BUCKET_SIZE35; |
| 3097 | int tcp_syn_bucket_limit = /* [N] per bucket limit */ |
| 3098 | 3 * TCP_SYN_BUCKET_SIZE35; |
| 3099 | int tcp_syn_use_limit = 100000; /* [N] reseed after uses */ |
| 3100 | |
| 3101 | struct pool syn_cache_pool; |
| 3102 | struct syn_cache_set tcp_syn_cache[2]; |
| 3103 | int tcp_syn_cache_active; |
| 3104 | struct mutex syn_cache_mtx = MUTEX_INITIALIZER(IPL_SOFTNET){ ((void *)0), ((((0x2)) > 0x0 && ((0x2)) < 0x9 ) ? 0x9 : ((0x2))), 0x0 }; |
| 3105 | |
| 3106 | #define SYN_HASH(sa, sp, dp, rand)(((sa)->s_addr ^ (rand)[0]) * (((((u_int32_t)(dp))<< 16) + ((u_int32_t)(sp))) ^ (rand)[4])) \ |
| 3107 | (((sa)->s_addr ^ (rand)[0]) * \ |
| 3108 | (((((u_int32_t)(dp))<<16) + ((u_int32_t)(sp))) ^ (rand)[4])) |
| 3109 | #ifndef INET61 |
| 3110 | #define SYN_HASHALL(hash, src, dst, rand)do { switch ((src)->sa_family) { case 2: hash = (((&satosin (src)->sin_addr)->s_addr ^ ((rand))[0]) * (((((u_int32_t )(satosin(dst)->sin_port))<<16) + ((u_int32_t)(satosin (src)->sin_port))) ^ ((rand))[4])); break; case 24: hash = (((&satosin6(src)->sin6_addr)->__u6_addr.__u6_addr32 [0] ^ ((rand))[0]) * ((&satosin6(src)->sin6_addr)-> __u6_addr.__u6_addr32[1] ^ ((rand))[1]) * ((&satosin6(src )->sin6_addr)->__u6_addr.__u6_addr32[2] ^ ((rand))[2]) * ((&satosin6(src)->sin6_addr)->__u6_addr.__u6_addr32 [3] ^ ((rand))[3]) * (((((u_int32_t)(satosin6(dst)->sin6_port ))<<16) + ((u_int32_t)(satosin6(src)->sin6_port))) ^ ((rand))[4])); break; default: hash = 0; } } while ( 0) \ |
| 3111 | do { \ |
| 3112 | hash = SYN_HASH(&satosin(src)->sin_addr, \(((&satosin(src)->sin_addr)->s_addr ^ ((rand))[0]) * (((((u_int32_t)(satosin(dst)->sin_port))<<16) + ((u_int32_t )(satosin(src)->sin_port))) ^ ((rand))[4])) |
| 3113 | satosin(src)->sin_port, \(((&satosin(src)->sin_addr)->s_addr ^ ((rand))[0]) * (((((u_int32_t)(satosin(dst)->sin_port))<<16) + ((u_int32_t )(satosin(src)->sin_port))) ^ ((rand))[4])) |
| 3114 | satosin(dst)->sin_port, (rand))(((&satosin(src)->sin_addr)->s_addr ^ ((rand))[0]) * (((((u_int32_t)(satosin(dst)->sin_port))<<16) + ((u_int32_t )(satosin(src)->sin_port))) ^ ((rand))[4])); \ |
| 3115 | } while (/*CONSTCOND*/ 0) |
| 3116 | #else |
| 3117 | #define SYN_HASH6(sa, sp, dp, rand)(((sa)->__u6_addr.__u6_addr32[0] ^ (rand)[0]) * ((sa)-> __u6_addr.__u6_addr32[1] ^ (rand)[1]) * ((sa)->__u6_addr.__u6_addr32 [2] ^ (rand)[2]) * ((sa)->__u6_addr.__u6_addr32[3] ^ (rand )[3]) * (((((u_int32_t)(dp))<<16) + ((u_int32_t)(sp))) ^ (rand)[4])) \ |
| 3118 | (((sa)->s6_addr32__u6_addr.__u6_addr32[0] ^ (rand)[0]) * \ |
| 3119 | ((sa)->s6_addr32__u6_addr.__u6_addr32[1] ^ (rand)[1]) * \ |
| 3120 | ((sa)->s6_addr32__u6_addr.__u6_addr32[2] ^ (rand)[2]) * \ |
| 3121 | ((sa)->s6_addr32__u6_addr.__u6_addr32[3] ^ (rand)[3]) * \ |
| 3122 | (((((u_int32_t)(dp))<<16) + ((u_int32_t)(sp))) ^ (rand)[4])) |
| 3123 | |
| 3124 | #define SYN_HASHALL(hash, src, dst, rand)do { switch ((src)->sa_family) { case 2: hash = (((&satosin (src)->sin_addr)->s_addr ^ ((rand))[0]) * (((((u_int32_t )(satosin(dst)->sin_port))<<16) + ((u_int32_t)(satosin (src)->sin_port))) ^ ((rand))[4])); break; case 24: hash = (((&satosin6(src)->sin6_addr)->__u6_addr.__u6_addr32 [0] ^ ((rand))[0]) * ((&satosin6(src)->sin6_addr)-> __u6_addr.__u6_addr32[1] ^ ((rand))[1]) * ((&satosin6(src )->sin6_addr)->__u6_addr.__u6_addr32[2] ^ ((rand))[2]) * ((&satosin6(src)->sin6_addr)->__u6_addr.__u6_addr32 [3] ^ ((rand))[3]) * (((((u_int32_t)(satosin6(dst)->sin6_port ))<<16) + ((u_int32_t)(satosin6(src)->sin6_port))) ^ ((rand))[4])); break; default: hash = 0; } } while ( 0) \ |
| 3125 | do { \ |
| 3126 | switch ((src)->sa_family) { \ |
| 3127 | case AF_INET2: \ |
| 3128 | hash = SYN_HASH(&satosin(src)->sin_addr, \(((&satosin(src)->sin_addr)->s_addr ^ ((rand))[0]) * (((((u_int32_t)(satosin(dst)->sin_port))<<16) + ((u_int32_t )(satosin(src)->sin_port))) ^ ((rand))[4])) |
| 3129 | satosin(src)->sin_port, \(((&satosin(src)->sin_addr)->s_addr ^ ((rand))[0]) * (((((u_int32_t)(satosin(dst)->sin_port))<<16) + ((u_int32_t )(satosin(src)->sin_port))) ^ ((rand))[4])) |
| 3130 | satosin(dst)->sin_port, (rand))(((&satosin(src)->sin_addr)->s_addr ^ ((rand))[0]) * (((((u_int32_t)(satosin(dst)->sin_port))<<16) + ((u_int32_t )(satosin(src)->sin_port))) ^ ((rand))[4])); \ |
| 3131 | break; \ |
| 3132 | case AF_INET624: \ |
| 3133 | hash = SYN_HASH6(&satosin6(src)->sin6_addr, \(((&satosin6(src)->sin6_addr)->__u6_addr.__u6_addr32 [0] ^ ((rand))[0]) * ((&satosin6(src)->sin6_addr)-> __u6_addr.__u6_addr32[1] ^ ((rand))[1]) * ((&satosin6(src )->sin6_addr)->__u6_addr.__u6_addr32[2] ^ ((rand))[2]) * ((&satosin6(src)->sin6_addr)->__u6_addr.__u6_addr32 [3] ^ ((rand))[3]) * (((((u_int32_t)(satosin6(dst)->sin6_port ))<<16) + ((u_int32_t)(satosin6(src)->sin6_port))) ^ ((rand))[4])) |
| 3134 | satosin6(src)->sin6_port, \(((&satosin6(src)->sin6_addr)->__u6_addr.__u6_addr32 [0] ^ ((rand))[0]) * ((&satosin6(src)->sin6_addr)-> __u6_addr.__u6_addr32[1] ^ ((rand))[1]) * ((&satosin6(src )->sin6_addr)->__u6_addr.__u6_addr32[2] ^ ((rand))[2]) * ((&satosin6(src)->sin6_addr)->__u6_addr.__u6_addr32 [3] ^ ((rand))[3]) * (((((u_int32_t)(satosin6(dst)->sin6_port ))<<16) + ((u_int32_t)(satosin6(src)->sin6_port))) ^ ((rand))[4])) |
| 3135 | satosin6(dst)->sin6_port, (rand))(((&satosin6(src)->sin6_addr)->__u6_addr.__u6_addr32 [0] ^ ((rand))[0]) * ((&satosin6(src)->sin6_addr)-> __u6_addr.__u6_addr32[1] ^ ((rand))[1]) * ((&satosin6(src )->sin6_addr)->__u6_addr.__u6_addr32[2] ^ ((rand))[2]) * ((&satosin6(src)->sin6_addr)->__u6_addr.__u6_addr32 [3] ^ ((rand))[3]) * (((((u_int32_t)(satosin6(dst)->sin6_port ))<<16) + ((u_int32_t)(satosin6(src)->sin6_port))) ^ ((rand))[4])); \ |
| 3136 | break; \ |
| 3137 | default: \ |
| 3138 | hash = 0; \ |
| 3139 | } \ |
| 3140 | } while (/*CONSTCOND*/0) |
| 3141 | #endif /* INET6 */ |
| 3142 | |
| 3143 | void |
| 3144 | syn_cache_rm(struct syn_cache *sc) |
| 3145 | { |
| 3146 | MUTEX_ASSERT_LOCKED(&syn_cache_mtx)do { if (((&syn_cache_mtx)->mtx_owner != ({struct cpu_info *__ci; asm volatile("movq %%gs:%P1,%0" : "=r" (__ci) :"n" (__builtin_offsetof (struct cpu_info, ci_self))); __ci;})) && !(panicstr || db_active)) panic("mutex %p not held in %s", (&syn_cache_mtx ), __func__); } while (0); |
| 3147 | |
| 3148 | KASSERT(!ISSET(sc->sc_dynflags, SCF_DEAD))((!((sc->sc_dynflags) & (0x0002U))) ? (void)0 : __assert ("diagnostic ", "/usr/src/sys/netinet/tcp_input.c", 3148, "!ISSET(sc->sc_dynflags, SCF_DEAD)" )); |
| 3149 | SET(sc->sc_dynflags, SCF_DEAD)((sc->sc_dynflags) |= (0x0002U)); |
| 3150 | TAILQ_REMOVE(&sc->sc_buckethead->sch_bucket, sc, sc_bucketq)do { if (((sc)->sc_bucketq.tqe_next) != ((void *)0)) (sc)-> sc_bucketq.tqe_next->sc_bucketq.tqe_prev = (sc)->sc_bucketq .tqe_prev; else (&sc->sc_buckethead->sch_bucket)-> tqh_last = (sc)->sc_bucketq.tqe_prev; *(sc)->sc_bucketq .tqe_prev = (sc)->sc_bucketq.tqe_next; ((sc)->sc_bucketq .tqe_prev) = ((void *)-1); ((sc)->sc_bucketq.tqe_next) = ( (void *)-1); } while (0); |
| 3151 | sc->sc_tp = NULL((void *)0); |
| 3152 | LIST_REMOVE(sc, sc_tpq)do { if ((sc)->sc_tpq.le_next != ((void *)0)) (sc)->sc_tpq .le_next->sc_tpq.le_prev = (sc)->sc_tpq.le_prev; *(sc)-> sc_tpq.le_prev = (sc)->sc_tpq.le_next; ((sc)->sc_tpq.le_prev ) = ((void *)-1); ((sc)->sc_tpq.le_next) = ((void *)-1); } while (0); |
| 3153 | refcnt_rele(&sc->sc_refcnt); |
| 3154 | sc->sc_buckethead->sch_length--; |
| 3155 | if (timeout_del(&sc->sc_timer)) |
| 3156 | refcnt_rele(&sc->sc_refcnt); |
| 3157 | sc->sc_set->scs_count--; |
| 3158 | } |
| 3159 | |
| 3160 | void |
| 3161 | syn_cache_put(struct syn_cache *sc) |
| 3162 | { |
| 3163 | if (refcnt_rele(&sc->sc_refcnt) == 0) |
| 3164 | return; |
| 3165 | |
| 3166 | /* Dealing with last reference, no lock needed. */ |
| 3167 | m_free(sc->sc_ipopts); |
| 3168 | rtfree(sc->sc_route4sc_route_u.route4.ro_rt); |
| 3169 | |
| 3170 | pool_put(&syn_cache_pool, sc); |
| 3171 | } |
| 3172 | |
| 3173 | void |
| 3174 | syn_cache_init(void) |
| 3175 | { |
| 3176 | int i; |
| 3177 | |
| 3178 | /* Initialize the hash buckets. */ |
| 3179 | tcp_syn_cache[0].scs_buckethead = mallocarray(tcp_syn_hash_size, |
| 3180 | sizeof(struct syn_cache_head), M_SYNCACHE139, M_WAITOK0x0001|M_ZERO0x0008); |
| 3181 | tcp_syn_cache[1].scs_buckethead = mallocarray(tcp_syn_hash_size, |
| 3182 | sizeof(struct syn_cache_head), M_SYNCACHE139, M_WAITOK0x0001|M_ZERO0x0008); |
| 3183 | tcp_syn_cache[0].scs_size = tcp_syn_hash_size; |
| 3184 | tcp_syn_cache[1].scs_size = tcp_syn_hash_size; |
| 3185 | for (i = 0; i < tcp_syn_hash_size; i++) { |
| 3186 | TAILQ_INIT(&tcp_syn_cache[0].scs_buckethead[i].sch_bucket)do { (&tcp_syn_cache[0].scs_buckethead[i].sch_bucket)-> tqh_first = ((void *)0); (&tcp_syn_cache[0].scs_buckethead [i].sch_bucket)->tqh_last = &(&tcp_syn_cache[0].scs_buckethead [i].sch_bucket)->tqh_first; } while (0); |
| 3187 | TAILQ_INIT(&tcp_syn_cache[1].scs_buckethead[i].sch_bucket)do { (&tcp_syn_cache[1].scs_buckethead[i].sch_bucket)-> tqh_first = ((void *)0); (&tcp_syn_cache[1].scs_buckethead [i].sch_bucket)->tqh_last = &(&tcp_syn_cache[1].scs_buckethead [i].sch_bucket)->tqh_first; } while (0); |
| 3188 | } |
| 3189 | |
| 3190 | /* Initialize the syn cache pool. */ |
| 3191 | pool_init(&syn_cache_pool, sizeof(struct syn_cache), 0, IPL_SOFTNET0x2, |
| 3192 | 0, "syncache", NULL((void *)0)); |
| 3193 | } |
| 3194 | |
| 3195 | void |
| 3196 | syn_cache_insert(struct syn_cache *sc, struct tcpcb *tp) |
| 3197 | { |
| 3198 | struct syn_cache_set *set = &tcp_syn_cache[tcp_syn_cache_active]; |
| 3199 | struct syn_cache_head *scp; |
| 3200 | struct syn_cache *sc2; |
| 3201 | int i; |
| 3202 | |
| 3203 | NET_ASSERT_LOCKED()do { int _s = rw_status(&netlock); if ((splassert_ctl > 0) && (_s != 0x0001UL && _s != 0x0002UL)) splassert_fail (0x0002UL, _s, __func__); } while (0); |
| 3204 | MUTEX_ASSERT_LOCKED(&syn_cache_mtx)do { if (((&syn_cache_mtx)->mtx_owner != ({struct cpu_info *__ci; asm volatile("movq %%gs:%P1,%0" : "=r" (__ci) :"n" (__builtin_offsetof (struct cpu_info, ci_self))); __ci;})) && !(panicstr || db_active)) panic("mutex %p not held in %s", (&syn_cache_mtx ), __func__); } while (0); |
| 3205 | |
| 3206 | /* |
| 3207 | * If there are no entries in the hash table, reinitialize |
| 3208 | * the hash secrets. To avoid useless cache swaps and |
| 3209 | * reinitialization, use it until the limit is reached. |
| 3210 | * An empty cache is also the opportunity to resize the hash. |
| 3211 | */ |
| 3212 | if (set->scs_count == 0 && set->scs_use <= 0) { |
| 3213 | set->scs_use = tcp_syn_use_limit; |
| 3214 | if (set->scs_size != tcp_syn_hash_size) { |
| 3215 | scp = mallocarray(tcp_syn_hash_size, sizeof(struct |
| 3216 | syn_cache_head), M_SYNCACHE139, M_NOWAIT0x0002|M_ZERO0x0008); |
| 3217 | if (scp == NULL((void *)0)) { |
| 3218 | /* Try again next time. */ |
| 3219 | set->scs_use = 0; |
| 3220 | } else { |
| 3221 | free(set->scs_buckethead, M_SYNCACHE139, |
| 3222 | set->scs_size * |
| 3223 | sizeof(struct syn_cache_head)); |
| 3224 | set->scs_buckethead = scp; |
| 3225 | set->scs_size = tcp_syn_hash_size; |
| 3226 | for (i = 0; i < tcp_syn_hash_size; i++) |
| 3227 | TAILQ_INIT(&scp[i].sch_bucket)do { (&scp[i].sch_bucket)->tqh_first = ((void *)0); (& scp[i].sch_bucket)->tqh_last = &(&scp[i].sch_bucket )->tqh_first; } while (0); |
| 3228 | } |
| 3229 | } |
| 3230 | arc4random_buf(set->scs_random, sizeof(set->scs_random)); |
| 3231 | tcpstat_inc(tcps_sc_seedrandom); |
| 3232 | } |
| 3233 | |
| 3234 | SYN_HASHALL(sc->sc_hash, &sc->sc_src.sa, &sc->sc_dst.sa,do { switch ((&sc->sc_src.sa)->sa_family) { case 2: sc->sc_hash = (((&satosin(&sc->sc_src.sa)-> sin_addr)->s_addr ^ ((set->scs_random))[0]) * (((((u_int32_t )(satosin(&sc->sc_dst.sa)->sin_port))<<16) + ( (u_int32_t)(satosin(&sc->sc_src.sa)->sin_port))) ^ ( (set->scs_random))[4])); break; case 24: sc->sc_hash = ( ((&satosin6(&sc->sc_src.sa)->sin6_addr)->__u6_addr .__u6_addr32[0] ^ ((set->scs_random))[0]) * ((&satosin6 (&sc->sc_src.sa)->sin6_addr)->__u6_addr.__u6_addr32 [1] ^ ((set->scs_random))[1]) * ((&satosin6(&sc-> sc_src.sa)->sin6_addr)->__u6_addr.__u6_addr32[2] ^ ((set ->scs_random))[2]) * ((&satosin6(&sc->sc_src.sa )->sin6_addr)->__u6_addr.__u6_addr32[3] ^ ((set->scs_random ))[3]) * (((((u_int32_t)(satosin6(&sc->sc_dst.sa)-> sin6_port))<<16) + ((u_int32_t)(satosin6(&sc->sc_src .sa)->sin6_port))) ^ ((set->scs_random))[4])); break; default : sc->sc_hash = 0; } } while ( 0) |
| 3235 | set->scs_random)do { switch ((&sc->sc_src.sa)->sa_family) { case 2: sc->sc_hash = (((&satosin(&sc->sc_src.sa)-> sin_addr)->s_addr ^ ((set->scs_random))[0]) * (((((u_int32_t )(satosin(&sc->sc_dst.sa)->sin_port))<<16) + ( (u_int32_t)(satosin(&sc->sc_src.sa)->sin_port))) ^ ( (set->scs_random))[4])); break; case 24: sc->sc_hash = ( ((&satosin6(&sc->sc_src.sa)->sin6_addr)->__u6_addr .__u6_addr32[0] ^ ((set->scs_random))[0]) * ((&satosin6 (&sc->sc_src.sa)->sin6_addr)->__u6_addr.__u6_addr32 [1] ^ ((set->scs_random))[1]) * ((&satosin6(&sc-> sc_src.sa)->sin6_addr)->__u6_addr.__u6_addr32[2] ^ ((set ->scs_random))[2]) * ((&satosin6(&sc->sc_src.sa )->sin6_addr)->__u6_addr.__u6_addr32[3] ^ ((set->scs_random ))[3]) * (((((u_int32_t)(satosin6(&sc->sc_dst.sa)-> sin6_port))<<16) + ((u_int32_t)(satosin6(&sc->sc_src .sa)->sin6_port))) ^ ((set->scs_random))[4])); break; default : sc->sc_hash = 0; } } while ( 0); |
| 3236 | scp = &set->scs_buckethead[sc->sc_hash % set->scs_size]; |
| 3237 | sc->sc_buckethead = scp; |
| 3238 | |
| 3239 | /* |
| 3240 | * Make sure that we don't overflow the per-bucket |
| 3241 | * limit or the total cache size limit. |
| 3242 | */ |
| 3243 | if (scp->sch_length >= tcp_syn_bucket_limit) { |
| 3244 | tcpstat_inc(tcps_sc_bucketoverflow); |
| 3245 | /* |
| 3246 | * Someone might attack our bucket hash function. Reseed |
| 3247 | * with random as soon as the passive syn cache gets empty. |
| 3248 | */ |
| 3249 | set->scs_use = 0; |
| 3250 | /* |
| 3251 | * The bucket is full. Toss the oldest element in the |
| 3252 | * bucket. This will be the first entry in the bucket. |
| 3253 | */ |
| 3254 | sc2 = TAILQ_FIRST(&scp->sch_bucket)((&scp->sch_bucket)->tqh_first); |
| 3255 | #ifdef DIAGNOSTIC1 |
| 3256 | /* |
| 3257 | * This should never happen; we should always find an |
| 3258 | * entry in our bucket. |
| 3259 | */ |
| 3260 | if (sc2 == NULL((void *)0)) |
| 3261 | panic("%s: bucketoverflow: impossible", __func__); |
| 3262 | #endif |
| 3263 | syn_cache_rm(sc2); |
| 3264 | syn_cache_put(sc2); |
| 3265 | } else if (set->scs_count >= tcp_syn_cache_limit) { |
| 3266 | struct syn_cache_head *scp2, *sce; |
| 3267 | |
| 3268 | tcpstat_inc(tcps_sc_overflowed); |
| 3269 | /* |
| 3270 | * The cache is full. Toss the oldest entry in the |
| 3271 | * first non-empty bucket we can find. |
| 3272 | * |
| 3273 | * XXX We would really like to toss the oldest |
| 3274 | * entry in the cache, but we hope that this |
| 3275 | * condition doesn't happen very often. |
| 3276 | */ |
| 3277 | scp2 = scp; |
| 3278 | if (TAILQ_EMPTY(&scp2->sch_bucket)(((&scp2->sch_bucket)->tqh_first) == ((void *)0))) { |
| 3279 | sce = &set->scs_buckethead[set->scs_size]; |
| 3280 | for (++scp2; scp2 != scp; scp2++) { |
| 3281 | if (scp2 >= sce) |
| 3282 | scp2 = &set->scs_buckethead[0]; |
| 3283 | if (! TAILQ_EMPTY(&scp2->sch_bucket)(((&scp2->sch_bucket)->tqh_first) == ((void *)0))) |
| 3284 | break; |
| 3285 | } |
| 3286 | #ifdef DIAGNOSTIC1 |
| 3287 | /* |
| 3288 | * This should never happen; we should always find a |
| 3289 | * non-empty bucket. |
| 3290 | */ |
| 3291 | if (scp2 == scp) |
| 3292 | panic("%s: cacheoverflow: impossible", |
| 3293 | __func__); |
| 3294 | #endif |
| 3295 | } |
| 3296 | sc2 = TAILQ_FIRST(&scp2->sch_bucket)((&scp2->sch_bucket)->tqh_first); |
| 3297 | syn_cache_rm(sc2); |
| 3298 | syn_cache_put(sc2); |
| 3299 | } |
| 3300 | |
| 3301 | /* |
| 3302 | * Initialize the entry's timer. We don't estimate RTT |
| 3303 | * with SYNs, so each packet starts with the default RTT |
| 3304 | * and each timer step has a fixed timeout value. |
| 3305 | */ |
| 3306 | sc->sc_rxttot = 0; |
| 3307 | sc->sc_rxtshift = 0; |
| 3308 | TCPT_RANGESET(sc->sc_rxtcur,do { (sc->sc_rxtcur) = (((3) * 1000) * tcp_backoff[sc-> sc_rxtshift]); if ((sc->sc_rxtcur) < (((1) * 1000))) (sc ->sc_rxtcur) = (((1) * 1000)); else if ((sc->sc_rxtcur) > (((64) * 1000))) (sc->sc_rxtcur) = (((64) * 1000)); } while ( 0) |
| 3309 | TCPTV_SRTTDFLT * tcp_backoff[sc->sc_rxtshift], TCPTV_MIN,do { (sc->sc_rxtcur) = (((3) * 1000) * tcp_backoff[sc-> sc_rxtshift]); if ((sc->sc_rxtcur) < (((1) * 1000))) (sc ->sc_rxtcur) = (((1) * 1000)); else if ((sc->sc_rxtcur) > (((64) * 1000))) (sc->sc_rxtcur) = (((64) * 1000)); } while ( 0) |
| 3310 | TCPTV_REXMTMAX)do { (sc->sc_rxtcur) = (((3) * 1000) * tcp_backoff[sc-> sc_rxtshift]); if ((sc->sc_rxtcur) < (((1) * 1000))) (sc ->sc_rxtcur) = (((1) * 1000)); else if ((sc->sc_rxtcur) > (((64) * 1000))) (sc->sc_rxtcur) = (((64) * 1000)); } while ( 0); |
| 3311 | if (timeout_add_msec(&sc->sc_timer, sc->sc_rxtcur)) |
| 3312 | refcnt_take(&sc->sc_refcnt); |
| 3313 | |
| 3314 | /* Link it from tcpcb entry */ |
| 3315 | refcnt_take(&sc->sc_refcnt); |
| 3316 | LIST_INSERT_HEAD(&tp->t_sc, sc, sc_tpq)do { if (((sc)->sc_tpq.le_next = (&tp->t_sc)->lh_first ) != ((void *)0)) (&tp->t_sc)->lh_first->sc_tpq. le_prev = &(sc)->sc_tpq.le_next; (&tp->t_sc)-> lh_first = (sc); (sc)->sc_tpq.le_prev = &(&tp-> t_sc)->lh_first; } while (0); |
| 3317 | |
| 3318 | /* Put it into the bucket. */ |
| 3319 | TAILQ_INSERT_TAIL(&scp->sch_bucket, sc, sc_bucketq)do { (sc)->sc_bucketq.tqe_next = ((void *)0); (sc)->sc_bucketq .tqe_prev = (&scp->sch_bucket)->tqh_last; *(&scp ->sch_bucket)->tqh_last = (sc); (&scp->sch_bucket )->tqh_last = &(sc)->sc_bucketq.tqe_next; } while ( 0); |
| 3320 | scp->sch_length++; |
| 3321 | sc->sc_set = set; |
| 3322 | set->scs_count++; |
| 3323 | set->scs_use--; |
| 3324 | |
| 3325 | tcpstat_inc(tcps_sc_added); |
| 3326 | |
| 3327 | /* |
| 3328 | * If the active cache has exceeded its use limit and |
| 3329 | * the passive syn cache is empty, exchange their roles. |
| 3330 | */ |
| 3331 | if (set->scs_use <= 0 && |
| 3332 | tcp_syn_cache[!tcp_syn_cache_active].scs_count == 0) |
| 3333 | tcp_syn_cache_active = !tcp_syn_cache_active; |
| 3334 | } |
| 3335 | |
| 3336 | /* |
| 3337 | * Walk the timer queues, looking for SYN,ACKs that need to be retransmitted. |
| 3338 | * If we have retransmitted an entry the maximum number of times, expire |
| 3339 | * that entry. |
| 3340 | */ |
| 3341 | void |
| 3342 | syn_cache_timer(void *arg) |
| 3343 | { |
| 3344 | struct syn_cache *sc = arg; |
| 3345 | uint64_t now; |
| 3346 | int lastref; |
| 3347 | |
| 3348 | mtx_enter(&syn_cache_mtx); |
| 3349 | if (ISSET(sc->sc_dynflags, SCF_DEAD)((sc->sc_dynflags) & (0x0002U))) |
| 3350 | goto freeit; |
| 3351 | |
| 3352 | if (__predict_false(sc->sc_rxtshift == TCP_MAXRXTSHIFT)__builtin_expect(((sc->sc_rxtshift == 12) != 0), 0)) { |
| 3353 | /* Drop it -- too many retransmissions. */ |
| 3354 | goto dropit; |
| 3355 | } |
| 3356 | |
| 3357 | /* |
| 3358 | * Compute the total amount of time this entry has |
| 3359 | * been on a queue. If this entry has been on longer |
| 3360 | * than the keep alive timer would allow, expire it. |
| 3361 | */ |
| 3362 | sc->sc_rxttot += sc->sc_rxtcur; |
| 3363 | if (sc->sc_rxttot >= READ_ONCE(tcptv_keep_init)({ typeof(tcptv_keep_init) __tmp = *(volatile typeof(tcptv_keep_init ) *)&(tcptv_keep_init); membar_datadep_consumer(); __tmp; })) |
| 3364 | goto dropit; |
| 3365 | |
| 3366 | /* Advance the timer back-off. */ |
| 3367 | sc->sc_rxtshift++; |
| 3368 | TCPT_RANGESET(sc->sc_rxtcur,do { (sc->sc_rxtcur) = (((3) * 1000) * tcp_backoff[sc-> sc_rxtshift]); if ((sc->sc_rxtcur) < (((1) * 1000))) (sc ->sc_rxtcur) = (((1) * 1000)); else if ((sc->sc_rxtcur) > (((64) * 1000))) (sc->sc_rxtcur) = (((64) * 1000)); } while ( 0) |
| 3369 | TCPTV_SRTTDFLT * tcp_backoff[sc->sc_rxtshift], TCPTV_MIN,do { (sc->sc_rxtcur) = (((3) * 1000) * tcp_backoff[sc-> sc_rxtshift]); if ((sc->sc_rxtcur) < (((1) * 1000))) (sc ->sc_rxtcur) = (((1) * 1000)); else if ((sc->sc_rxtcur) > (((64) * 1000))) (sc->sc_rxtcur) = (((64) * 1000)); } while ( 0) |
| 3370 | TCPTV_REXMTMAX)do { (sc->sc_rxtcur) = (((3) * 1000) * tcp_backoff[sc-> sc_rxtshift]); if ((sc->sc_rxtcur) < (((1) * 1000))) (sc ->sc_rxtcur) = (((1) * 1000)); else if ((sc->sc_rxtcur) > (((64) * 1000))) (sc->sc_rxtcur) = (((64) * 1000)); } while ( 0); |
| 3371 | if (timeout_add_msec(&sc->sc_timer, sc->sc_rxtcur)) |
| 3372 | refcnt_take(&sc->sc_refcnt); |
| 3373 | mtx_leave(&syn_cache_mtx); |
| 3374 | |
| 3375 | NET_LOCK()do { rw_enter_write(&netlock); } while (0); |
| 3376 | now = tcp_now(); |
| 3377 | (void) syn_cache_respond(sc, NULL((void *)0), now); |
| 3378 | tcpstat_inc(tcps_sc_retransmitted); |
| 3379 | NET_UNLOCK()do { rw_exit_write(&netlock); } while (0); |
| 3380 | |
| 3381 | syn_cache_put(sc); |
| 3382 | return; |
| 3383 | |
| 3384 | dropit: |
| 3385 | tcpstat_inc(tcps_sc_timed_out); |
| 3386 | syn_cache_rm(sc); |
| 3387 | /* Decrement reference of the timer and free object after remove. */ |
| 3388 | lastref = refcnt_rele(&sc->sc_refcnt); |
| 3389 | KASSERT(lastref == 0)((lastref == 0) ? (void)0 : __assert("diagnostic ", "/usr/src/sys/netinet/tcp_input.c" , 3389, "lastref == 0")); |
| 3390 | (void)lastref; |
| 3391 | freeit: |
| 3392 | mtx_leave(&syn_cache_mtx); |
| 3393 | syn_cache_put(sc); |
| 3394 | } |
| 3395 | |
| 3396 | /* |
| 3397 | * Remove syn cache created by the specified tcb entry, |
| 3398 | * because this does not make sense to keep them |
| 3399 | * (if there's no tcb entry, syn cache entry will never be used) |
| 3400 | */ |
| 3401 | void |
| 3402 | syn_cache_cleanup(struct tcpcb *tp) |
| 3403 | { |
| 3404 | struct syn_cache *sc, *nsc; |
| 3405 | |
| 3406 | NET_ASSERT_LOCKED()do { int _s = rw_status(&netlock); if ((splassert_ctl > 0) && (_s != 0x0001UL && _s != 0x0002UL)) splassert_fail (0x0002UL, _s, __func__); } while (0); |
| 3407 | |
| 3408 | mtx_enter(&syn_cache_mtx); |
| 3409 | LIST_FOREACH_SAFE(sc, &tp->t_sc, sc_tpq, nsc)for ((sc) = ((&tp->t_sc)->lh_first); (sc) && ((nsc) = ((sc)->sc_tpq.le_next), 1); (sc) = (nsc)) { |
| 3410 | #ifdef DIAGNOSTIC1 |
| 3411 | if (sc->sc_tp != tp) |
| 3412 | panic("invalid sc_tp in syn_cache_cleanup"); |
| 3413 | #endif |
| 3414 | syn_cache_rm(sc); |
| 3415 | syn_cache_put(sc); |
| 3416 | } |
| 3417 | mtx_leave(&syn_cache_mtx); |
| 3418 | |
| 3419 | KASSERT(LIST_EMPTY(&tp->t_sc))(((((&tp->t_sc)->lh_first) == ((void *)0))) ? (void )0 : __assert("diagnostic ", "/usr/src/sys/netinet/tcp_input.c" , 3419, "LIST_EMPTY(&tp->t_sc)")); |
| 3420 | } |
| 3421 | |
| 3422 | /* |
| 3423 | * Find an entry in the syn cache. |
| 3424 | */ |
| 3425 | struct syn_cache * |
| 3426 | syn_cache_lookup(struct sockaddr *src, struct sockaddr *dst, |
| 3427 | struct syn_cache_head **headp, u_int rtableid) |
| 3428 | { |
| 3429 | struct syn_cache_set *sets[2]; |
| 3430 | struct syn_cache *sc; |
| 3431 | struct syn_cache_head *scp; |
| 3432 | u_int32_t hash; |
| 3433 | int i; |
| 3434 | |
| 3435 | NET_ASSERT_LOCKED()do { int _s = rw_status(&netlock); if ((splassert_ctl > 0) && (_s != 0x0001UL && _s != 0x0002UL)) splassert_fail (0x0002UL, _s, __func__); } while (0); |
| 3436 | MUTEX_ASSERT_LOCKED(&syn_cache_mtx)do { if (((&syn_cache_mtx)->mtx_owner != ({struct cpu_info *__ci; asm volatile("movq %%gs:%P1,%0" : "=r" (__ci) :"n" (__builtin_offsetof (struct cpu_info, ci_self))); __ci;})) && !(panicstr || db_active)) panic("mutex %p not held in %s", (&syn_cache_mtx ), __func__); } while (0); |
| 3437 | |
| 3438 | /* Check the active cache first, the passive cache is likely empty. */ |
| 3439 | sets[0] = &tcp_syn_cache[tcp_syn_cache_active]; |
| 3440 | sets[1] = &tcp_syn_cache[!tcp_syn_cache_active]; |
| 3441 | for (i = 0; i < 2; i++) { |
| 3442 | if (sets[i]->scs_count == 0) |
| 3443 | continue; |
| 3444 | SYN_HASHALL(hash, src, dst, sets[i]->scs_random)do { switch ((src)->sa_family) { case 2: hash = (((&satosin (src)->sin_addr)->s_addr ^ ((sets[i]->scs_random))[0 ]) * (((((u_int32_t)(satosin(dst)->sin_port))<<16) + ((u_int32_t)(satosin(src)->sin_port))) ^ ((sets[i]->scs_random ))[4])); break; case 24: hash = (((&satosin6(src)->sin6_addr )->__u6_addr.__u6_addr32[0] ^ ((sets[i]->scs_random))[0 ]) * ((&satosin6(src)->sin6_addr)->__u6_addr.__u6_addr32 [1] ^ ((sets[i]->scs_random))[1]) * ((&satosin6(src)-> sin6_addr)->__u6_addr.__u6_addr32[2] ^ ((sets[i]->scs_random ))[2]) * ((&satosin6(src)->sin6_addr)->__u6_addr.__u6_addr32 [3] ^ ((sets[i]->scs_random))[3]) * (((((u_int32_t)(satosin6 (dst)->sin6_port))<<16) + ((u_int32_t)(satosin6(src) ->sin6_port))) ^ ((sets[i]->scs_random))[4])); break; default : hash = 0; } } while ( 0); |
| 3445 | scp = &sets[i]->scs_buckethead[hash % sets[i]->scs_size]; |
| 3446 | *headp = scp; |
| 3447 | TAILQ_FOREACH(sc, &scp->sch_bucket, sc_bucketq)for((sc) = ((&scp->sch_bucket)->tqh_first); (sc) != ((void *)0); (sc) = ((sc)->sc_bucketq.tqe_next)) { |
| 3448 | if (sc->sc_hash != hash) |
| 3449 | continue; |
| 3450 | if (!bcmp(&sc->sc_src, src, src->sa_len) && |
| 3451 | !bcmp(&sc->sc_dst, dst, dst->sa_len) && |
| 3452 | rtable_l2(rtableid) == rtable_l2(sc->sc_rtableid)) |
| 3453 | return (sc); |
| 3454 | } |
| 3455 | } |
| 3456 | return (NULL((void *)0)); |
| 3457 | } |
| 3458 | |
| 3459 | /* |
| 3460 | * This function gets called when we receive an ACK for a |
| 3461 | * socket in the LISTEN state. We look up the connection |
| 3462 | * in the syn cache, and if its there, we pull it out of |
| 3463 | * the cache and turn it into a full-blown connection in |
| 3464 | * the SYN-RECEIVED state. |
| 3465 | * |
| 3466 | * The return values may not be immediately obvious, and their effects |
| 3467 | * can be subtle, so here they are: |
| 3468 | * |
| 3469 | * NULL SYN was not found in cache; caller should drop the |
| 3470 | * packet and send an RST. |
| 3471 | * |
| 3472 | * -1 We were unable to create the new connection, and are |
| 3473 | * aborting it. An ACK,RST is being sent to the peer |
| 3474 | * (unless we got screwy sequence numbers; see below), |
| 3475 | * because the 3-way handshake has been completed. Caller |
| 3476 | * should not free the mbuf, since we may be using it. If |
| 3477 | * we are not, we will free it. |
| 3478 | * |
| 3479 | * Otherwise, the return value is a pointer to the new socket |
| 3480 | * associated with the connection. |
| 3481 | */ |
| 3482 | struct socket * |
| 3483 | syn_cache_get(struct sockaddr *src, struct sockaddr *dst, struct tcphdr *th, |
| 3484 | u_int hlen, u_int tlen, struct socket *so, struct mbuf *m, uint64_t now) |
| 3485 | { |
| 3486 | struct syn_cache *sc; |
| 3487 | struct syn_cache_head *scp; |
| 3488 | struct inpcb *inp, *oldinp; |
| 3489 | struct tcpcb *tp = NULL((void *)0); |
| 3490 | struct mbuf *am; |
| 3491 | struct socket *oso; |
| 3492 | u_int rtableid; |
| 3493 | |
| 3494 | NET_ASSERT_LOCKED()do { int _s = rw_status(&netlock); if ((splassert_ctl > 0) && (_s != 0x0001UL && _s != 0x0002UL)) splassert_fail (0x0002UL, _s, __func__); } while (0); |
| 3495 | |
| 3496 | mtx_enter(&syn_cache_mtx); |
| 3497 | sc = syn_cache_lookup(src, dst, &scp, sotoinpcb(so)((struct inpcb *)(so)->so_pcb)->inp_rtableid); |
| 3498 | if (sc == NULL((void *)0)) { |
| 3499 | mtx_leave(&syn_cache_mtx); |
| 3500 | return (NULL((void *)0)); |
| 3501 | } |
| 3502 | |
| 3503 | /* |
| 3504 | * Verify the sequence and ack numbers. Try getting the correct |
| 3505 | * response again. |
| 3506 | */ |
| 3507 | if ((th->th_ack != sc->sc_iss + 1) || |
| 3508 | SEQ_LEQ(th->th_seq, sc->sc_irs)((int)((th->th_seq)-(sc->sc_irs)) <= 0) || |
| 3509 | SEQ_GT(th->th_seq, sc->sc_irs + 1 + sc->sc_win)((int)((th->th_seq)-(sc->sc_irs + 1 + sc->sc_win)) > 0)) { |
| 3510 | refcnt_take(&sc->sc_refcnt); |
| 3511 | mtx_leave(&syn_cache_mtx); |
| 3512 | (void) syn_cache_respond(sc, m, now); |
| 3513 | syn_cache_put(sc); |
| 3514 | return ((struct socket *)(-1)); |
| 3515 | } |
| 3516 | |
| 3517 | /* Remove this cache entry */ |
| 3518 | syn_cache_rm(sc); |
| 3519 | mtx_leave(&syn_cache_mtx); |
| 3520 | |
| 3521 | /* |
| 3522 | * Ok, create the full blown connection, and set things up |
| 3523 | * as they would have been set up if we had created the |
| 3524 | * connection when the SYN arrived. If we can't create |
| 3525 | * the connection, abort it. |
| 3526 | */ |
| 3527 | oso = so; |
| 3528 | so = sonewconn(so, SS_ISCONNECTED0x002, M_DONTWAIT0x0002); |
| 3529 | if (so == NULL((void *)0)) |
| 3530 | goto resetandabort; |
| 3531 | |
| 3532 | oldinp = sotoinpcb(oso)((struct inpcb *)(oso)->so_pcb); |
| 3533 | inp = sotoinpcb(so)((struct inpcb *)(so)->so_pcb); |
| 3534 | |
| 3535 | #ifdef IPSEC1 |
| 3536 | /* |
| 3537 | * We need to copy the required security levels |
| 3538 | * from the old pcb. Ditto for any other |
| 3539 | * IPsec-related information. |
| 3540 | */ |
| 3541 | memcpy(inp->inp_seclevel, oldinp->inp_seclevel,__builtin_memcpy((inp->inp_seclevel), (oldinp->inp_seclevel ), (sizeof(oldinp->inp_seclevel))) |
| 3542 | sizeof(oldinp->inp_seclevel))__builtin_memcpy((inp->inp_seclevel), (oldinp->inp_seclevel ), (sizeof(oldinp->inp_seclevel))); |
| 3543 | #endif /* IPSEC */ |
| 3544 | #ifdef INET61 |
| 3545 | /* |
| 3546 | * inp still has the OLD in_pcb stuff, set the |
| 3547 | * v6-related flags on the new guy, too. |
| 3548 | */ |
| 3549 | inp->inp_flags |= (oldinp->inp_flags & INP_IPV60x100); |
| 3550 | if (inp->inp_flags & INP_IPV60x100) { |
| 3551 | inp->inp_ipv6inp_hu.hu_ipv6.ip6_hlimip6_ctlun.ip6_un1.ip6_un1_hlim = oldinp->inp_ipv6inp_hu.hu_ipv6.ip6_hlimip6_ctlun.ip6_un1.ip6_un1_hlim; |
| 3552 | inp->inp_hops = oldinp->inp_hops; |
| 3553 | } else |
| 3554 | #endif /* INET6 */ |
| 3555 | { |
| 3556 | inp->inp_ipinp_hu.hu_ip.ip_ttl = oldinp->inp_ipinp_hu.hu_ip.ip_ttl; |
| 3557 | inp->inp_options = ip_srcroute(m); |
| 3558 | if (inp->inp_options == NULL((void *)0)) { |
| 3559 | inp->inp_options = sc->sc_ipopts; |
| 3560 | sc->sc_ipopts = NULL((void *)0); |
| 3561 | } |
| 3562 | } |
| 3563 | |
| 3564 | /* inherit rtable from listening socket */ |
| 3565 | rtableid = sc->sc_rtableid; |
| 3566 | #if NPF1 > 0 |
| 3567 | if (m->m_pkthdrM_dat.MH.MH_pkthdr.pf.flags & PF_TAG_DIVERTED0x08) { |
| 3568 | struct pf_divert *divert; |
| 3569 | |
| 3570 | divert = pf_find_divert(m); |
| 3571 | KASSERT(divert != NULL)((divert != ((void *)0)) ? (void)0 : __assert("diagnostic ", "/usr/src/sys/netinet/tcp_input.c" , 3571, "divert != NULL")); |
| 3572 | rtableid = divert->rdomain; |
| 3573 | } |
| 3574 | #endif |
| 3575 | in_pcbset_laddr(inp, dst, rtableid); |
| 3576 | |
| 3577 | /* |
| 3578 | * Give the new socket our cached route reference. |
| 3579 | */ |
| 3580 | if (src->sa_family == AF_INET2) |
| 3581 | inp->inp_routeinp_ru.ru_route = sc->sc_route4sc_route_u.route4; /* struct assignment */ |
| 3582 | #ifdef INET61 |
| 3583 | else |
| 3584 | inp->inp_route6inp_ru.ru_route6 = sc->sc_route6sc_route_u.route6; |
| 3585 | #endif |
| 3586 | sc->sc_route4sc_route_u.route4.ro_rt = NULL((void *)0); |
| 3587 | |
| 3588 | am = m_get(M_DONTWAIT0x0002, MT_SONAME3); /* XXX */ |
| 3589 | if (am == NULL((void *)0)) |
| 3590 | goto resetandabort; |
| 3591 | am->m_lenm_hdr.mh_len = src->sa_len; |
| 3592 | memcpy(mtod(am, caddr_t), src, src->sa_len)__builtin_memcpy((((caddr_t)((am)->m_hdr.mh_data))), (src) , (src->sa_len)); |
| 3593 | if (in_pcbconnect(inp, am)) { |
| 3594 | (void) m_free(am); |
| 3595 | goto resetandabort; |
| 3596 | } |
| 3597 | (void) m_free(am); |
| 3598 | |
| 3599 | tp = intotcpcb(inp)((struct tcpcb *)(inp)->inp_ppcb); |
| 3600 | tp->t_flags = sototcpcb(oso)(((struct tcpcb *)(((struct inpcb *)(oso)->so_pcb))->inp_ppcb ))->t_flags & (TF_NOPUSH0x02000000U|TF_NODELAY0x0004U); |
| 3601 | if (sc->sc_request_r_scale != 15) { |
| 3602 | tp->requested_s_scale = sc->sc_requested_s_scale; |
| 3603 | tp->request_r_scale = sc->sc_request_r_scale; |
| 3604 | tp->t_flags |= TF_REQ_SCALE0x0020U|TF_RCVD_SCALE0x0040U; |
| 3605 | } |
| 3606 | if (ISSET(sc->sc_fixflags, SCF_TIMESTAMP)((sc->sc_fixflags) & (0x0010U))) |
| 3607 | tp->t_flags |= TF_REQ_TSTMP0x0080U|TF_RCVD_TSTMP0x0100U; |
| 3608 | |
| 3609 | tp->t_template = tcp_template(tp); |
| 3610 | if (tp->t_template == 0) { |
| 3611 | tp = tcp_drop(tp, ENOBUFS55); /* destroys socket */ |
Value stored to 'tp' is never read | |
| 3612 | so = NULL((void *)0); |
| 3613 | goto abort; |
| 3614 | } |
| 3615 | tp->sack_enable = ISSET(sc->sc_fixflags, SCF_SACK_PERMIT)((sc->sc_fixflags) & (0x0020U)); |
| 3616 | tp->ts_modulate = sc->sc_modulate; |
| 3617 | tp->ts_recent = sc->sc_timestamp; |
| 3618 | tp->iss = sc->sc_iss; |
| 3619 | tp->irs = sc->sc_irs; |
| 3620 | tcp_sendseqinit(tp)(tp)->snd_una = (tp)->snd_nxt = (tp)->snd_max = (tp) ->snd_up = (tp)->iss; |
| 3621 | tp->snd_last = tp->snd_una; |
| 3622 | #ifdef TCP_ECN1 |
| 3623 | if (ISSET(sc->sc_fixflags, SCF_ECN_PERMIT)((sc->sc_fixflags) & (0x0040U))) { |
| 3624 | tp->t_flags |= TF_ECN_PERMIT0x00008000U; |
| 3625 | tcpstat_inc(tcps_ecn_accepts); |
| 3626 | } |
| 3627 | #endif |
| 3628 | if (ISSET(sc->sc_fixflags, SCF_SACK_PERMIT)((sc->sc_fixflags) & (0x0020U))) |
| 3629 | tp->t_flags |= TF_SACK_PERMIT0x0200U; |
| 3630 | #ifdef TCP_SIGNATURE1 |
| 3631 | if (ISSET(sc->sc_fixflags, SCF_SIGNATURE)((sc->sc_fixflags) & (0x0080U))) |
| 3632 | tp->t_flags |= TF_SIGNATURE0x0400U; |
| 3633 | #endif |
| 3634 | tcp_rcvseqinit(tp)(tp)->rcv_adv = (tp)->rcv_nxt = (tp)->irs + 1; |
| 3635 | tp->t_state = TCPS_SYN_RECEIVED3; |
| 3636 | tp->t_rcvtime = now; |
| 3637 | tp->t_sndtime = now; |
| 3638 | tp->t_rcvacktime = now; |
| 3639 | tp->t_sndacktime = now; |
| 3640 | TCP_TIMER_ARM(tp, TCPT_KEEP, tcptv_keep_init)do { (((tp)->t_flags) |= (0x04000000U << (2))); timeout_add_msec (&(tp)->t_timer[(2)], (tcptv_keep_init)); } while (0); |
| 3641 | tcpstat_inc(tcps_accepts); |
| 3642 | |
| 3643 | tcp_mss(tp, sc->sc_peermaxseg); /* sets t_maxseg */ |
| 3644 | if (sc->sc_peermaxseg) |
| 3645 | tcp_mss_update(tp); |
| 3646 | /* Reset initial window to 1 segment for retransmit */ |
| 3647 | if (READ_ONCE(sc->sc_rxtshift)({ typeof(sc->sc_rxtshift) __tmp = *(volatile typeof(sc-> sc_rxtshift) *)&(sc->sc_rxtshift); membar_datadep_consumer (); __tmp; }) > 0) |
| 3648 | tp->snd_cwnd = tp->t_maxseg; |
| 3649 | tp->snd_wl1 = sc->sc_irs; |
| 3650 | tp->rcv_up = sc->sc_irs + 1; |
| 3651 | |
| 3652 | /* |
| 3653 | * This is what would have happened in tcp_output() when |
| 3654 | * the SYN,ACK was sent. |
| 3655 | */ |
| 3656 | tp->snd_up = tp->snd_una; |
| 3657 | tp->snd_max = tp->snd_nxt = tp->iss+1; |
| 3658 | TCP_TIMER_ARM(tp, TCPT_REXMT, tp->t_rxtcur)do { (((tp)->t_flags) |= (0x04000000U << (0))); timeout_add_msec (&(tp)->t_timer[(0)], (tp->t_rxtcur)); } while (0); |
| 3659 | if (sc->sc_win > 0 && SEQ_GT(tp->rcv_nxt + sc->sc_win, tp->rcv_adv)((int)((tp->rcv_nxt + sc->sc_win)-(tp->rcv_adv)) > 0)) |
| 3660 | tp->rcv_adv = tp->rcv_nxt + sc->sc_win; |
| 3661 | tp->last_ack_sent = tp->rcv_nxt; |
| 3662 | |
| 3663 | tcpstat_inc(tcps_sc_completed); |
| 3664 | syn_cache_put(sc); |
| 3665 | return (so); |
| 3666 | |
| 3667 | resetandabort: |
| 3668 | tcp_respond(NULL((void *)0), mtod(m, caddr_t)((caddr_t)((m)->m_hdr.mh_data)), th, (tcp_seq)0, th->th_ack, TH_RST0x04, |
| 3669 | m->m_pkthdrM_dat.MH.MH_pkthdr.ph_rtableid, now); |
| 3670 | abort: |
| 3671 | m_freem(m); |
| 3672 | if (so != NULL((void *)0)) |
| 3673 | soabort(so); |
| 3674 | syn_cache_put(sc); |
| 3675 | tcpstat_inc(tcps_sc_aborted); |
| 3676 | return ((struct socket *)(-1)); |
| 3677 | } |
| 3678 | |
| 3679 | /* |
| 3680 | * This function is called when we get a RST for a |
| 3681 | * non-existent connection, so that we can see if the |
| 3682 | * connection is in the syn cache. If it is, zap it. |
| 3683 | */ |
| 3684 | |
| 3685 | void |
| 3686 | syn_cache_reset(struct sockaddr *src, struct sockaddr *dst, struct tcphdr *th, |
| 3687 | u_int rtableid) |
| 3688 | { |
| 3689 | struct syn_cache *sc; |
| 3690 | struct syn_cache_head *scp; |
| 3691 | |
| 3692 | NET_ASSERT_LOCKED()do { int _s = rw_status(&netlock); if ((splassert_ctl > 0) && (_s != 0x0001UL && _s != 0x0002UL)) splassert_fail (0x0002UL, _s, __func__); } while (0); |
| 3693 | |
| 3694 | mtx_enter(&syn_cache_mtx); |
| 3695 | sc = syn_cache_lookup(src, dst, &scp, rtableid); |
| 3696 | if (sc == NULL((void *)0)) { |
| 3697 | mtx_leave(&syn_cache_mtx); |
| 3698 | return; |
| 3699 | } |
| 3700 | if (SEQ_LT(th->th_seq, sc->sc_irs)((int)((th->th_seq)-(sc->sc_irs)) < 0) || |
| 3701 | SEQ_GT(th->th_seq, sc->sc_irs + 1)((int)((th->th_seq)-(sc->sc_irs + 1)) > 0)) { |
| 3702 | mtx_leave(&syn_cache_mtx); |
| 3703 | return; |
| 3704 | } |
| 3705 | syn_cache_rm(sc); |
| 3706 | mtx_leave(&syn_cache_mtx); |
| 3707 | tcpstat_inc(tcps_sc_reset); |
| 3708 | syn_cache_put(sc); |
| 3709 | } |
| 3710 | |
| 3711 | void |
| 3712 | syn_cache_unreach(struct sockaddr *src, struct sockaddr *dst, struct tcphdr *th, |
| 3713 | u_int rtableid) |
| 3714 | { |
| 3715 | struct syn_cache *sc; |
| 3716 | struct syn_cache_head *scp; |
| 3717 | |
| 3718 | NET_ASSERT_LOCKED()do { int _s = rw_status(&netlock); if ((splassert_ctl > 0) && (_s != 0x0001UL && _s != 0x0002UL)) splassert_fail (0x0002UL, _s, __func__); } while (0); |
| 3719 | |
| 3720 | mtx_enter(&syn_cache_mtx); |
| 3721 | sc = syn_cache_lookup(src, dst, &scp, rtableid); |
| 3722 | if (sc == NULL((void *)0)) { |
| 3723 | mtx_leave(&syn_cache_mtx); |
| 3724 | return; |
| 3725 | } |
| 3726 | /* If the sequence number != sc_iss, then it's a bogus ICMP msg */ |
| 3727 | if (ntohl (th->th_seq)(__uint32_t)(__builtin_constant_p(th->th_seq) ? (__uint32_t )(((__uint32_t)(th->th_seq) & 0xff) << 24 | ((__uint32_t )(th->th_seq) & 0xff00) << 8 | ((__uint32_t)(th-> th_seq) & 0xff0000) >> 8 | ((__uint32_t)(th->th_seq ) & 0xff000000) >> 24) : __swap32md(th->th_seq)) != sc->sc_iss) { |
| 3728 | mtx_leave(&syn_cache_mtx); |
| 3729 | return; |
| 3730 | } |
| 3731 | |
| 3732 | /* |
| 3733 | * If we've retransmitted 3 times and this is our second error, |
| 3734 | * we remove the entry. Otherwise, we allow it to continue on. |
| 3735 | * This prevents us from incorrectly nuking an entry during a |
| 3736 | * spurious network outage. |
| 3737 | * |
| 3738 | * See tcp_notify(). |
| 3739 | */ |
| 3740 | if (!ISSET(sc->sc_dynflags, SCF_UNREACH)((sc->sc_dynflags) & (0x0001U)) || sc->sc_rxtshift < 3) { |
| 3741 | SET(sc->sc_dynflags, SCF_UNREACH)((sc->sc_dynflags) |= (0x0001U)); |
| 3742 | mtx_leave(&syn_cache_mtx); |
| 3743 | return; |
| 3744 | } |
| 3745 | |
| 3746 | syn_cache_rm(sc); |
| 3747 | mtx_leave(&syn_cache_mtx); |
| 3748 | tcpstat_inc(tcps_sc_unreach); |
| 3749 | syn_cache_put(sc); |
| 3750 | } |
| 3751 | |
| 3752 | /* |
| 3753 | * Given a LISTEN socket and an inbound SYN request, add |
| 3754 | * this to the syn cache, and send back a segment: |
| 3755 | * <SEQ=ISS><ACK=RCV_NXT><CTL=SYN,ACK> |
| 3756 | * to the source. |
| 3757 | * |
| 3758 | * IMPORTANT NOTE: We do _NOT_ ACK data that might accompany the SYN. |
| 3759 | * Doing so would require that we hold onto the data and deliver it |
| 3760 | * to the application. However, if we are the target of a SYN-flood |
| 3761 | * DoS attack, an attacker could send data which would eventually |
| 3762 | * consume all available buffer space if it were ACKed. By not ACKing |
| 3763 | * the data, we avoid this DoS scenario. |
| 3764 | */ |
| 3765 | |
| 3766 | int |
| 3767 | syn_cache_add(struct sockaddr *src, struct sockaddr *dst, struct tcphdr *th, |
| 3768 | u_int iphlen, struct socket *so, struct mbuf *m, u_char *optp, int optlen, |
| 3769 | struct tcp_opt_info *oi, tcp_seq *issp, uint64_t now) |
| 3770 | { |
| 3771 | struct tcpcb tb, *tp; |
| 3772 | long win; |
| 3773 | struct syn_cache *sc; |
| 3774 | struct syn_cache_head *scp; |
| 3775 | struct mbuf *ipopts; |
| 3776 | |
| 3777 | NET_ASSERT_LOCKED()do { int _s = rw_status(&netlock); if ((splassert_ctl > 0) && (_s != 0x0001UL && _s != 0x0002UL)) splassert_fail (0x0002UL, _s, __func__); } while (0); |
| 3778 | |
| 3779 | tp = sototcpcb(so)(((struct tcpcb *)(((struct inpcb *)(so)->so_pcb))->inp_ppcb )); |
| 3780 | |
| 3781 | /* |
| 3782 | * RFC1122 4.2.3.10, p. 104: discard bcast/mcast SYN |
| 3783 | * |
| 3784 | * Note this check is performed in tcp_input() very early on. |
| 3785 | */ |
| 3786 | |
| 3787 | /* |
| 3788 | * Initialize some local state. |
| 3789 | */ |
| 3790 | win = sbspace(so, &so->so_rcv); |
| 3791 | if (win > TCP_MAXWIN65535) |
| 3792 | win = TCP_MAXWIN65535; |
| 3793 | |
| 3794 | bzero(&tb, sizeof(tb))__builtin_bzero((&tb), (sizeof(tb))); |
| 3795 | #ifdef TCP_SIGNATURE1 |
| 3796 | if (optp || (tp->t_flags & TF_SIGNATURE0x0400U)) { |
| 3797 | #else |
| 3798 | if (optp) { |
| 3799 | #endif |
| 3800 | tb.pf = tp->pf; |
| 3801 | tb.sack_enable = tp->sack_enable; |
| 3802 | tb.t_flags = tcp_do_rfc1323 ? (TF_REQ_SCALE0x0020U|TF_REQ_TSTMP0x0080U) : 0; |
| 3803 | #ifdef TCP_SIGNATURE1 |
| 3804 | if (tp->t_flags & TF_SIGNATURE0x0400U) |
| 3805 | tb.t_flags |= TF_SIGNATURE0x0400U; |
| 3806 | #endif |
| 3807 | tb.t_state = TCPS_LISTEN1; |
| 3808 | if (tcp_dooptions(&tb, optp, optlen, th, m, iphlen, oi, |
| 3809 | sotoinpcb(so)((struct inpcb *)(so)->so_pcb)->inp_rtableid, now)) |
| 3810 | return (-1); |
| 3811 | } |
| 3812 | |
| 3813 | switch (src->sa_family) { |
| 3814 | case AF_INET2: |
| 3815 | /* |
| 3816 | * Remember the IP options, if any. |
| 3817 | */ |
| 3818 | ipopts = ip_srcroute(m); |
| 3819 | break; |
| 3820 | default: |
| 3821 | ipopts = NULL((void *)0); |
| 3822 | } |
| 3823 | |
| 3824 | /* |
| 3825 | * See if we already have an entry for this connection. |
| 3826 | * If we do, resend the SYN,ACK. We do not count this |
| 3827 | * as a retransmission (XXX though maybe we should). |
| 3828 | */ |
| 3829 | mtx_enter(&syn_cache_mtx); |
| 3830 | sc = syn_cache_lookup(src, dst, &scp, sotoinpcb(so)((struct inpcb *)(so)->so_pcb)->inp_rtableid); |
| 3831 | if (sc != NULL((void *)0)) { |
| 3832 | refcnt_take(&sc->sc_refcnt); |
| 3833 | mtx_leave(&syn_cache_mtx); |
| 3834 | tcpstat_inc(tcps_sc_dupesyn); |
| 3835 | if (ipopts) { |
| 3836 | /* |
| 3837 | * If we were remembering a previous source route, |
| 3838 | * forget it and use the new one we've been given. |
| 3839 | */ |
| 3840 | m_free(sc->sc_ipopts); |
| 3841 | sc->sc_ipopts = ipopts; |
| 3842 | } |
| 3843 | sc->sc_timestamp = tb.ts_recent; |
| 3844 | if (syn_cache_respond(sc, m, now) == 0) { |
| 3845 | tcpstat_inc(tcps_sndacks); |
| 3846 | tcpstat_inc(tcps_sndtotal); |
| 3847 | } |
| 3848 | syn_cache_put(sc); |
| 3849 | return (0); |
| 3850 | } |
| 3851 | mtx_leave(&syn_cache_mtx); |
| 3852 | |
| 3853 | sc = pool_get(&syn_cache_pool, PR_NOWAIT0x0002|PR_ZERO0x0008); |
| 3854 | if (sc == NULL((void *)0)) { |
| 3855 | m_free(ipopts); |
| 3856 | return (-1); |
| 3857 | } |
| 3858 | refcnt_init_trace(&sc->sc_refcnt, DT_REFCNT_IDX_SYNCACHE6); |
| 3859 | timeout_set_flags(&sc->sc_timer, syn_cache_timer, sc, |
| 3860 | KCLOCK_NONE(-1), TIMEOUT_PROC0x01 | TIMEOUT_MPSAFE0x10); |
| 3861 | |
| 3862 | /* |
| 3863 | * Fill in the cache, and put the necessary IP and TCP |
| 3864 | * options into the reply. |
| 3865 | */ |
| 3866 | memcpy(&sc->sc_src, src, src->sa_len)__builtin_memcpy((&sc->sc_src), (src), (src->sa_len )); |
| 3867 | memcpy(&sc->sc_dst, dst, dst->sa_len)__builtin_memcpy((&sc->sc_dst), (dst), (dst->sa_len )); |
| 3868 | sc->sc_rtableid = sotoinpcb(so)((struct inpcb *)(so)->so_pcb)->inp_rtableid; |
| 3869 | sc->sc_ipopts = ipopts; |
| 3870 | sc->sc_irs = th->th_seq; |
| 3871 | |
| 3872 | sc->sc_iss = issp ? *issp : arc4random(); |
| 3873 | sc->sc_peermaxseg = oi->maxseg; |
| 3874 | sc->sc_ourmaxseg = tcp_mss_adv(m, sc->sc_src.sa.sa_family); |
| 3875 | sc->sc_win = win; |
| 3876 | sc->sc_timestamp = tb.ts_recent; |
| 3877 | if ((tb.t_flags & (TF_REQ_TSTMP0x0080U|TF_RCVD_TSTMP0x0100U)) == |
| 3878 | (TF_REQ_TSTMP0x0080U|TF_RCVD_TSTMP0x0100U)) { |
| 3879 | SET(sc->sc_fixflags, SCF_TIMESTAMP)((sc->sc_fixflags) |= (0x0010U)); |
| 3880 | sc->sc_modulate = arc4random(); |
| 3881 | } |
| 3882 | if ((tb.t_flags & (TF_RCVD_SCALE0x0040U|TF_REQ_SCALE0x0020U)) == |
| 3883 | (TF_RCVD_SCALE0x0040U|TF_REQ_SCALE0x0020U)) { |
| 3884 | sc->sc_requested_s_scale = tb.requested_s_scale; |
| 3885 | sc->sc_request_r_scale = 0; |
| 3886 | /* |
| 3887 | * Pick the smallest possible scaling factor that |
| 3888 | * will still allow us to scale up to sb_max. |
| 3889 | * |
| 3890 | * We do this because there are broken firewalls that |
| 3891 | * will corrupt the window scale option, leading to |
| 3892 | * the other endpoint believing that our advertised |
| 3893 | * window is unscaled. At scale factors larger than |
| 3894 | * 5 the unscaled window will drop below 1500 bytes, |
| 3895 | * leading to serious problems when traversing these |
| 3896 | * broken firewalls. |
| 3897 | * |
| 3898 | * With the default sbmax of 256K, a scale factor |
| 3899 | * of 3 will be chosen by this algorithm. Those who |
| 3900 | * choose a larger sbmax should watch out |
| 3901 | * for the compatibility problems mentioned above. |
| 3902 | * |
| 3903 | * RFC1323: The Window field in a SYN (i.e., a <SYN> |
| 3904 | * or <SYN,ACK>) segment itself is never scaled. |
| 3905 | */ |
| 3906 | while (sc->sc_request_r_scale < TCP_MAX_WINSHIFT14 && |
| 3907 | (TCP_MAXWIN65535 << sc->sc_request_r_scale) < sb_max) |
| 3908 | sc->sc_request_r_scale++; |
| 3909 | } else { |
| 3910 | sc->sc_requested_s_scale = 15; |
| 3911 | sc->sc_request_r_scale = 15; |
| 3912 | } |
| 3913 | #ifdef TCP_ECN1 |
| 3914 | /* |
| 3915 | * if both ECE and CWR flag bits are set, peer is ECN capable. |
| 3916 | */ |
| 3917 | if (tcp_do_ecn && |
| 3918 | (th->th_flags & (TH_ECE0x40|TH_CWR0x80)) == (TH_ECE0x40|TH_CWR0x80)) |
| 3919 | SET(sc->sc_fixflags, SCF_ECN_PERMIT)((sc->sc_fixflags) |= (0x0040U)); |
| 3920 | #endif |
| 3921 | /* |
| 3922 | * Set SCF_SACK_PERMIT if peer did send a SACK_PERMITTED option |
| 3923 | * (i.e., if tcp_dooptions() did set TF_SACK_PERMIT). |
| 3924 | */ |
| 3925 | if (tb.sack_enable && (tb.t_flags & TF_SACK_PERMIT0x0200U)) |
| 3926 | SET(sc->sc_fixflags, SCF_SACK_PERMIT)((sc->sc_fixflags) |= (0x0020U)); |
| 3927 | #ifdef TCP_SIGNATURE1 |
| 3928 | if (tb.t_flags & TF_SIGNATURE0x0400U) |
| 3929 | SET(sc->sc_fixflags, SCF_SIGNATURE)((sc->sc_fixflags) |= (0x0080U)); |
| 3930 | #endif |
| 3931 | sc->sc_tp = tp; |
| 3932 | if (syn_cache_respond(sc, m, now) == 0) { |
| 3933 | mtx_enter(&syn_cache_mtx); |
| 3934 | /* |
| 3935 | * XXXSMP Currently exclusive netlock prevents another insert |
| 3936 | * after our syn_cache_lookup() and before syn_cache_insert(). |
| 3937 | * Double insert should be handled and not rely on netlock. |
| 3938 | */ |
| 3939 | syn_cache_insert(sc, tp); |
| 3940 | mtx_leave(&syn_cache_mtx); |
| 3941 | tcpstat_inc(tcps_sndacks); |
| 3942 | tcpstat_inc(tcps_sndtotal); |
| 3943 | } else { |
| 3944 | syn_cache_put(sc); |
| 3945 | tcpstat_inc(tcps_sc_dropped); |
| 3946 | } |
| 3947 | |
| 3948 | return (0); |
| 3949 | } |
| 3950 | |
| 3951 | int |
| 3952 | syn_cache_respond(struct syn_cache *sc, struct mbuf *m, uint64_t now) |
| 3953 | { |
| 3954 | u_int8_t *optp; |
| 3955 | int optlen, error; |
| 3956 | u_int16_t tlen; |
| 3957 | struct ip *ip = NULL((void *)0); |
| 3958 | #ifdef INET61 |
| 3959 | struct ip6_hdr *ip6 = NULL((void *)0); |
| 3960 | #endif |
| 3961 | struct tcphdr *th; |
| 3962 | u_int hlen; |
| 3963 | struct inpcb *inp; |
| 3964 | |
| 3965 | NET_ASSERT_LOCKED()do { int _s = rw_status(&netlock); if ((splassert_ctl > 0) && (_s != 0x0001UL && _s != 0x0002UL)) splassert_fail (0x0002UL, _s, __func__); } while (0); |
| 3966 | |
| 3967 | switch (sc->sc_src.sa.sa_family) { |
| 3968 | case AF_INET2: |
| 3969 | hlen = sizeof(struct ip); |
| 3970 | break; |
| 3971 | #ifdef INET61 |
| 3972 | case AF_INET624: |
| 3973 | hlen = sizeof(struct ip6_hdr); |
| 3974 | break; |
| 3975 | #endif |
| 3976 | default: |
| 3977 | m_freem(m); |
| 3978 | return (EAFNOSUPPORT47); |
| 3979 | } |
| 3980 | |
| 3981 | /* Compute the size of the TCP options. */ |
| 3982 | optlen = 4 + (sc->sc_request_r_scale != 15 ? 4 : 0) + |
| 3983 | (ISSET(sc->sc_fixflags, SCF_SACK_PERMIT)((sc->sc_fixflags) & (0x0020U)) ? 4 : 0) + |
| 3984 | #ifdef TCP_SIGNATURE1 |
| 3985 | (ISSET(sc->sc_fixflags, SCF_SIGNATURE)((sc->sc_fixflags) & (0x0080U)) ? TCPOLEN_SIGLEN(18 +2) : 0) + |
| 3986 | #endif |
| 3987 | (ISSET(sc->sc_fixflags, SCF_TIMESTAMP)((sc->sc_fixflags) & (0x0010U)) ? TCPOLEN_TSTAMP_APPA(10 +2) : 0); |
| 3988 | |
| 3989 | tlen = hlen + sizeof(struct tcphdr) + optlen; |
| 3990 | |
| 3991 | /* |
| 3992 | * Create the IP+TCP header from scratch. |
| 3993 | */ |
| 3994 | m_freem(m); |
| 3995 | #ifdef DIAGNOSTIC1 |
| 3996 | if (max_linkhdr + tlen > MCLBYTES(1 << 11)) |
| 3997 | return (ENOBUFS55); |
| 3998 | #endif |
| 3999 | MGETHDR(m, M_DONTWAIT, MT_DATA)m = m_gethdr((0x0002), (1)); |
| 4000 | if (m && max_linkhdr + tlen > MHLEN((256 - sizeof(struct m_hdr)) - sizeof(struct pkthdr))) { |
| 4001 | MCLGET(m, M_DONTWAIT)(void) m_clget((m), (0x0002), (1 << 11)); |
| 4002 | if ((m->m_flagsm_hdr.mh_flags & M_EXT0x0001) == 0) { |
| 4003 | m_freem(m); |
| 4004 | m = NULL((void *)0); |
| 4005 | } |
| 4006 | } |
| 4007 | if (m == NULL((void *)0)) |
| 4008 | return (ENOBUFS55); |
| 4009 | |
| 4010 | /* Fixup the mbuf. */ |
| 4011 | m->m_datam_hdr.mh_data += max_linkhdr; |
| 4012 | m->m_lenm_hdr.mh_len = m->m_pkthdrM_dat.MH.MH_pkthdr.len = tlen; |
| 4013 | m->m_pkthdrM_dat.MH.MH_pkthdr.ph_ifidx = 0; |
| 4014 | m->m_pkthdrM_dat.MH.MH_pkthdr.ph_rtableid = sc->sc_rtableid; |
| 4015 | memset(mtod(m, u_char *), 0, tlen)__builtin_memset((((u_char *)((m)->m_hdr.mh_data))), (0), ( tlen)); |
| 4016 | |
| 4017 | switch (sc->sc_src.sa.sa_family) { |
| 4018 | case AF_INET2: |
| 4019 | ip = mtod(m, struct ip *)((struct ip *)((m)->m_hdr.mh_data)); |
| 4020 | ip->ip_dst = sc->sc_src.sin.sin_addr; |
| 4021 | ip->ip_src = sc->sc_dst.sin.sin_addr; |
| 4022 | ip->ip_p = IPPROTO_TCP6; |
| 4023 | th = (struct tcphdr *)(ip + 1); |
| 4024 | th->th_dport = sc->sc_src.sin.sin_port; |
| 4025 | th->th_sport = sc->sc_dst.sin.sin_port; |
| 4026 | break; |
| 4027 | #ifdef INET61 |
| 4028 | case AF_INET624: |
| 4029 | ip6 = mtod(m, struct ip6_hdr *)((struct ip6_hdr *)((m)->m_hdr.mh_data)); |
| 4030 | ip6->ip6_dst = sc->sc_src.sin6.sin6_addr; |
| 4031 | ip6->ip6_src = sc->sc_dst.sin6.sin6_addr; |
| 4032 | ip6->ip6_nxtip6_ctlun.ip6_un1.ip6_un1_nxt = IPPROTO_TCP6; |
| 4033 | th = (struct tcphdr *)(ip6 + 1); |
| 4034 | th->th_dport = sc->sc_src.sin6.sin6_port; |
| 4035 | th->th_sport = sc->sc_dst.sin6.sin6_port; |
| 4036 | break; |
| 4037 | #endif |
| 4038 | } |
| 4039 | |
| 4040 | th->th_seq = htonl(sc->sc_iss)(__uint32_t)(__builtin_constant_p(sc->sc_iss) ? (__uint32_t )(((__uint32_t)(sc->sc_iss) & 0xff) << 24 | ((__uint32_t )(sc->sc_iss) & 0xff00) << 8 | ((__uint32_t)(sc-> sc_iss) & 0xff0000) >> 8 | ((__uint32_t)(sc->sc_iss ) & 0xff000000) >> 24) : __swap32md(sc->sc_iss)); |
| 4041 | th->th_ack = htonl(sc->sc_irs + 1)(__uint32_t)(__builtin_constant_p(sc->sc_irs + 1) ? (__uint32_t )(((__uint32_t)(sc->sc_irs + 1) & 0xff) << 24 | ( (__uint32_t)(sc->sc_irs + 1) & 0xff00) << 8 | (( __uint32_t)(sc->sc_irs + 1) & 0xff0000) >> 8 | ( (__uint32_t)(sc->sc_irs + 1) & 0xff000000) >> 24 ) : __swap32md(sc->sc_irs + 1)); |
| 4042 | th->th_off = (sizeof(struct tcphdr) + optlen) >> 2; |
| 4043 | th->th_flags = TH_SYN0x02|TH_ACK0x10; |
| 4044 | #ifdef TCP_ECN1 |
| 4045 | /* Set ECE for SYN-ACK if peer supports ECN. */ |
| 4046 | if (tcp_do_ecn && ISSET(sc->sc_fixflags, SCF_ECN_PERMIT)((sc->sc_fixflags) & (0x0040U))) |
| 4047 | th->th_flags |= TH_ECE0x40; |
| 4048 | #endif |
| 4049 | th->th_win = htons(sc->sc_win)(__uint16_t)(__builtin_constant_p(sc->sc_win) ? (__uint16_t )(((__uint16_t)(sc->sc_win) & 0xffU) << 8 | ((__uint16_t )(sc->sc_win) & 0xff00U) >> 8) : __swap16md(sc-> sc_win)); |
| 4050 | /* th_sum already 0 */ |
| 4051 | /* th_urp already 0 */ |
| 4052 | |
| 4053 | /* Tack on the TCP options. */ |
| 4054 | optp = (u_int8_t *)(th + 1); |
| 4055 | *optp++ = TCPOPT_MAXSEG2; |
| 4056 | *optp++ = 4; |
| 4057 | *optp++ = (sc->sc_ourmaxseg >> 8) & 0xff; |
| 4058 | *optp++ = sc->sc_ourmaxseg & 0xff; |
| 4059 | |
| 4060 | /* Include SACK_PERMIT_HDR option if peer has already done so. */ |
| 4061 | if (ISSET(sc->sc_fixflags, SCF_SACK_PERMIT)((sc->sc_fixflags) & (0x0020U))) { |
| 4062 | *((u_int32_t *)optp) = htonl(TCPOPT_SACK_PERMIT_HDR)(__uint32_t)(__builtin_constant_p((1<<24|1<<16|4<< 8|2)) ? (__uint32_t)(((__uint32_t)((1<<24|1<<16|4 <<8|2)) & 0xff) << 24 | ((__uint32_t)((1<< 24|1<<16|4<<8|2)) & 0xff00) << 8 | ((__uint32_t )((1<<24|1<<16|4<<8|2)) & 0xff0000) >> 8 | ((__uint32_t)((1<<24|1<<16|4<<8|2)) & 0xff000000) >> 24) : __swap32md((1<<24|1<< 16|4<<8|2))); |
| 4063 | optp += 4; |
| 4064 | } |
| 4065 | |
| 4066 | if (sc->sc_request_r_scale != 15) { |
| 4067 | *((u_int32_t *)optp) = htonl(TCPOPT_NOP << 24 |(__uint32_t)(__builtin_constant_p(1 << 24 | 3 << 16 | 3 << 8 | sc->sc_request_r_scale) ? (__uint32_t)(( (__uint32_t)(1 << 24 | 3 << 16 | 3 << 8 | sc ->sc_request_r_scale) & 0xff) << 24 | ((__uint32_t )(1 << 24 | 3 << 16 | 3 << 8 | sc->sc_request_r_scale ) & 0xff00) << 8 | ((__uint32_t)(1 << 24 | 3 << 16 | 3 << 8 | sc->sc_request_r_scale) & 0xff0000 ) >> 8 | ((__uint32_t)(1 << 24 | 3 << 16 | 3 << 8 | sc->sc_request_r_scale) & 0xff000000) >> 24) : __swap32md(1 << 24 | 3 << 16 | 3 << 8 | sc->sc_request_r_scale)) |
| 4068 | TCPOPT_WINDOW << 16 | TCPOLEN_WINDOW << 8 |(__uint32_t)(__builtin_constant_p(1 << 24 | 3 << 16 | 3 << 8 | sc->sc_request_r_scale) ? (__uint32_t)(( (__uint32_t)(1 << 24 | 3 << 16 | 3 << 8 | sc ->sc_request_r_scale) & 0xff) << 24 | ((__uint32_t )(1 << 24 | 3 << 16 | 3 << 8 | sc->sc_request_r_scale ) & 0xff00) << 8 | ((__uint32_t)(1 << 24 | 3 << 16 | 3 << 8 | sc->sc_request_r_scale) & 0xff0000 ) >> 8 | ((__uint32_t)(1 << 24 | 3 << 16 | 3 << 8 | sc->sc_request_r_scale) & 0xff000000) >> 24) : __swap32md(1 << 24 | 3 << 16 | 3 << 8 | sc->sc_request_r_scale)) |
| 4069 | sc->sc_request_r_scale)(__uint32_t)(__builtin_constant_p(1 << 24 | 3 << 16 | 3 << 8 | sc->sc_request_r_scale) ? (__uint32_t)(( (__uint32_t)(1 << 24 | 3 << 16 | 3 << 8 | sc ->sc_request_r_scale) & 0xff) << 24 | ((__uint32_t )(1 << 24 | 3 << 16 | 3 << 8 | sc->sc_request_r_scale ) & 0xff00) << 8 | ((__uint32_t)(1 << 24 | 3 << 16 | 3 << 8 | sc->sc_request_r_scale) & 0xff0000 ) >> 8 | ((__uint32_t)(1 << 24 | 3 << 16 | 3 << 8 | sc->sc_request_r_scale) & 0xff000000) >> 24) : __swap32md(1 << 24 | 3 << 16 | 3 << 8 | sc->sc_request_r_scale)); |
| 4070 | optp += 4; |
| 4071 | } |
| 4072 | |
| 4073 | if (ISSET(sc->sc_fixflags, SCF_TIMESTAMP)((sc->sc_fixflags) & (0x0010U))) { |
| 4074 | u_int32_t *lp = (u_int32_t *)(optp); |
| 4075 | /* Form timestamp option as shown in appendix A of RFC 1323. */ |
| 4076 | *lp++ = htonl(TCPOPT_TSTAMP_HDR)(__uint32_t)(__builtin_constant_p((1<<24|1<<16|8<< 8|10)) ? (__uint32_t)(((__uint32_t)((1<<24|1<<16| 8<<8|10)) & 0xff) << 24 | ((__uint32_t)((1<< 24|1<<16|8<<8|10)) & 0xff00) << 8 | ((__uint32_t )((1<<24|1<<16|8<<8|10)) & 0xff0000) >> 8 | ((__uint32_t)((1<<24|1<<16|8<<8|10)) & 0xff000000) >> 24) : __swap32md((1<<24|1<< 16|8<<8|10))); |
| 4077 | *lp++ = htonl(now + sc->sc_modulate)(__uint32_t)(__builtin_constant_p(now + sc->sc_modulate) ? (__uint32_t)(((__uint32_t)(now + sc->sc_modulate) & 0xff ) << 24 | ((__uint32_t)(now + sc->sc_modulate) & 0xff00) << 8 | ((__uint32_t)(now + sc->sc_modulate) & 0xff0000) >> 8 | ((__uint32_t)(now + sc->sc_modulate ) & 0xff000000) >> 24) : __swap32md(now + sc->sc_modulate )); |
| 4078 | *lp = htonl(sc->sc_timestamp)(__uint32_t)(__builtin_constant_p(sc->sc_timestamp) ? (__uint32_t )(((__uint32_t)(sc->sc_timestamp) & 0xff) << 24 | ((__uint32_t)(sc->sc_timestamp) & 0xff00) << 8 | ((__uint32_t)(sc->sc_timestamp) & 0xff0000) >> 8 | ((__uint32_t)(sc->sc_timestamp) & 0xff000000) >> 24) : __swap32md(sc->sc_timestamp)); |
| 4079 | optp += TCPOLEN_TSTAMP_APPA(10 +2); |
| 4080 | } |
| 4081 | |
| 4082 | #ifdef TCP_SIGNATURE1 |
| 4083 | if (ISSET(sc->sc_fixflags, SCF_SIGNATURE)((sc->sc_fixflags) & (0x0080U))) { |
| 4084 | union sockaddr_union src, dst; |
| 4085 | struct tdb *tdb; |
| 4086 | |
| 4087 | bzero(&src, sizeof(union sockaddr_union))__builtin_bzero((&src), (sizeof(union sockaddr_union))); |
| 4088 | bzero(&dst, sizeof(union sockaddr_union))__builtin_bzero((&dst), (sizeof(union sockaddr_union))); |
| 4089 | src.sa.sa_len = sc->sc_src.sa.sa_len; |
| 4090 | src.sa.sa_family = sc->sc_src.sa.sa_family; |
| 4091 | dst.sa.sa_len = sc->sc_dst.sa.sa_len; |
| 4092 | dst.sa.sa_family = sc->sc_dst.sa.sa_family; |
| 4093 | |
| 4094 | switch (sc->sc_src.sa.sa_family) { |
| 4095 | case 0: /*default to PF_INET*/ |
| 4096 | case AF_INET2: |
| 4097 | src.sin.sin_addr = mtod(m, struct ip *)((struct ip *)((m)->m_hdr.mh_data))->ip_src; |
| 4098 | dst.sin.sin_addr = mtod(m, struct ip *)((struct ip *)((m)->m_hdr.mh_data))->ip_dst; |
| 4099 | break; |
| 4100 | #ifdef INET61 |
| 4101 | case AF_INET624: |
| 4102 | src.sin6.sin6_addr = mtod(m, struct ip6_hdr *)((struct ip6_hdr *)((m)->m_hdr.mh_data))->ip6_src; |
| 4103 | dst.sin6.sin6_addr = mtod(m, struct ip6_hdr *)((struct ip6_hdr *)((m)->m_hdr.mh_data))->ip6_dst; |
| 4104 | break; |
| 4105 | #endif /* INET6 */ |
| 4106 | } |
| 4107 | |
| 4108 | tdb = gettdbbysrcdst(rtable_l2(sc->sc_rtableid),gettdbbysrcdst_dir((rtable_l2(sc->sc_rtableid)),(0),(& src),(&dst),(6),0) |
| 4109 | 0, &src, &dst, IPPROTO_TCP)gettdbbysrcdst_dir((rtable_l2(sc->sc_rtableid)),(0),(& src),(&dst),(6),0); |
| 4110 | if (tdb == NULL((void *)0)) { |
| 4111 | m_freem(m); |
| 4112 | return (EPERM1); |
| 4113 | } |
| 4114 | |
| 4115 | /* Send signature option */ |
| 4116 | *(optp++) = TCPOPT_SIGNATURE19; |
| 4117 | *(optp++) = TCPOLEN_SIGNATURE18; |
| 4118 | |
| 4119 | if (tcp_signature(tdb, sc->sc_src.sa.sa_family, m, th, |
| 4120 | hlen, 0, optp) < 0) { |
| 4121 | m_freem(m); |
| 4122 | tdb_unref(tdb); |
| 4123 | return (EINVAL22); |
| 4124 | } |
| 4125 | tdb_unref(tdb); |
| 4126 | optp += 16; |
| 4127 | |
| 4128 | /* Pad options list to the next 32 bit boundary and |
| 4129 | * terminate it. |
| 4130 | */ |
| 4131 | *optp++ = TCPOPT_NOP1; |
| 4132 | *optp++ = TCPOPT_EOL0; |
| 4133 | } |
| 4134 | #endif /* TCP_SIGNATURE */ |
| 4135 | |
| 4136 | SET(m->m_pkthdr.csum_flags, M_TCP_CSUM_OUT)((m->M_dat.MH.MH_pkthdr.csum_flags) |= (0x0002)); |
| 4137 | |
| 4138 | /* use IPsec policy and ttl from listening socket, on SYN ACK */ |
| 4139 | mtx_enter(&syn_cache_mtx); |
| 4140 | inp = sc->sc_tp ? sc->sc_tp->t_inpcb : NULL((void *)0); |
| 4141 | mtx_leave(&syn_cache_mtx); |
| 4142 | |
| 4143 | /* |
| 4144 | * Fill in some straggling IP bits. Note the stack expects |
| 4145 | * ip_len to be in host order, for convenience. |
| 4146 | */ |
| 4147 | switch (sc->sc_src.sa.sa_family) { |
| 4148 | case AF_INET2: |
| 4149 | ip->ip_len = htons(tlen)(__uint16_t)(__builtin_constant_p(tlen) ? (__uint16_t)(((__uint16_t )(tlen) & 0xffU) << 8 | ((__uint16_t)(tlen) & 0xff00U ) >> 8) : __swap16md(tlen)); |
| 4150 | ip->ip_ttl = inp ? inp->inp_ipinp_hu.hu_ip.ip_ttl : ip_defttl; |
| 4151 | if (inp != NULL((void *)0)) |
| 4152 | ip->ip_tos = inp->inp_ipinp_hu.hu_ip.ip_tos; |
| 4153 | |
| 4154 | error = ip_output(m, sc->sc_ipopts, &sc->sc_route4sc_route_u.route4, |
| 4155 | (ip_mtudisc ? IP_MTUDISC0x0800 : 0), NULL((void *)0), |
| 4156 | inp ? inp->inp_seclevel : NULL((void *)0), 0); |
| 4157 | break; |
| 4158 | #ifdef INET61 |
| 4159 | case AF_INET624: |
| 4160 | ip6->ip6_vfcip6_ctlun.ip6_un2_vfc &= ~IPV6_VERSION_MASK0xf0; |
| 4161 | ip6->ip6_vfcip6_ctlun.ip6_un2_vfc |= IPV6_VERSION0x60; |
| 4162 | /* ip6_plen will be updated in ip6_output() */ |
| 4163 | ip6->ip6_hlimip6_ctlun.ip6_un1.ip6_un1_hlim = in6_selecthlim(inp); |
| 4164 | /* leave flowlabel = 0, it is legal and require no state mgmt */ |
| 4165 | |
| 4166 | error = ip6_output(m, NULL((void *)0) /*XXX*/, &sc->sc_route6sc_route_u.route6, 0, |
| 4167 | NULL((void *)0), inp ? inp->inp_seclevel : NULL((void *)0)); |
| 4168 | break; |
| 4169 | #endif |
| 4170 | } |
| 4171 | return (error); |
| 4172 | } |