sys/netinet/tcp_lro.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2007, Myricom Inc.
   5  * Copyright (c) 2008, Intel Corporation.
   6  * Copyright (c) 2012 The FreeBSD Foundation
   7  * Copyright (c) 2016-2021 Mellanox Technologies.
   8  * All rights reserved.
   9  *
  10  * Portions of this software were developed by Bjoern Zeeb
  11  * under sponsorship from the FreeBSD Foundation.
  12  *
  13  * Redistribution and use in source and binary forms, with or without
  14  * modification, are permitted provided that the following conditions
  15  * are met:
  16  * 1. Redistributions of source code must retain the above copyright
  17  *    notice, this list of conditions and the following disclaimer.
  18  * 2. Redistributions in binary form must reproduce the above copyright
  19  *    notice, this list of conditions and the following disclaimer in the
  20  *    documentation and/or other materials provided with the distribution.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #include <sys/cdefs.h>
  36 __FBSDID("$FreeBSD$");
  37
  38 #include "opt_inet.h"
  39 #include "opt_inet6.h"
  40
  41 #include <sys/param.h>
  42 #include <sys/systm.h>
  43 #include <sys/kernel.h>
  44 #include <sys/malloc.h>
  45 #include <sys/mbuf.h>
  46 #include <sys/socket.h>
  47 #include <sys/socketvar.h>
  48 #include <sys/sockbuf.h>
  49 #include <sys/sysctl.h>
  50
  51 #include <net/if.h>
  52 #include <net/if_var.h>
  53 #include <net/ethernet.h>
  54 #include <net/bpf.h>
  55 #include <net/vnet.h>
  56 #include <net/if_dl.h>
  57 #include <net/if_media.h>
  58 #include <net/if_types.h>
  59 #include <net/infiniband.h>
  60 #include <net/if_lagg.h>
  61
  62 #include <netinet/in_systm.h>
  63 #include <netinet/in.h>
  64 #include <netinet/ip6.h>
  65 #include <netinet/ip.h>
  66 #include <netinet/ip_var.h>
  67 #include <netinet/in_pcb.h>
  68 #include <netinet6/in6_pcb.h>
  69 #include <netinet/tcp.h>
  70 #include <netinet/tcp_seq.h>
  71 #include <netinet/tcp_lro.h>
  72 #include <netinet/tcp_var.h>
  73 #include <netinet/tcpip.h>
  74 #include <netinet/tcp_hpts.h>
  75 #include <netinet/tcp_log_buf.h>
  76 #include <netinet/tcp_fsm.h>
  77 #include <netinet/udp.h>
  78 #include <netinet6/ip6_var.h>
  79
  80 #include <machine/in_cksum.h>
  81
  82 static MALLOC_DEFINE(M_LRO, "LRO", "LRO control structures");
  83
  84 #define TCP_LRO_TS_OPTION \
  85     ntohl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | \
  86           (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP)
  87
  88 static void     tcp_lro_rx_done(struct lro_ctrl *lc);
  89 static int      tcp_lro_rx_common(struct lro_ctrl *lc, struct mbuf *m,
  90                     uint32_t csum, bool use_hash);
  91
  92 #ifdef TCPHPTS
  93 static bool     do_bpf_strip_and_compress(struct inpcb *, struct lro_ctrl *,
  94                 struct lro_entry *, struct mbuf **, struct mbuf **, struct mbuf **,
  95                 bool *, bool, bool, struct ifnet *, bool);
  96
  97 #endif
  98
  99 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, lro,  CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
 100     "TCP LRO");
 101
 102 static long tcplro_stacks_wanting_mbufq;
 103 counter_u64_t tcp_inp_lro_direct_queue;
 104 counter_u64_t tcp_inp_lro_wokeup_queue;
 105 counter_u64_t tcp_inp_lro_compressed;
 106 counter_u64_t tcp_inp_lro_locks_taken;
 107 counter_u64_t tcp_extra_mbuf;
 108 counter_u64_t tcp_would_have_but;
 109 counter_u64_t tcp_comp_total;
 110 counter_u64_t tcp_uncomp_total;
 111 counter_u64_t tcp_bad_csums;
 112
 113 static unsigned tcp_lro_entries = TCP_LRO_ENTRIES;
 114 SYSCTL_UINT(_net_inet_tcp_lro, OID_AUTO, entries,
 115     CTLFLAG_RDTUN | CTLFLAG_MPSAFE, &tcp_lro_entries, 0,
 116     "default number of LRO entries");
 117
 118 static uint32_t tcp_lro_cpu_set_thresh = TCP_LRO_CPU_DECLARATION_THRESH;
 119 SYSCTL_UINT(_net_inet_tcp_lro, OID_AUTO, lro_cpu_threshold,
 120     CTLFLAG_RDTUN | CTLFLAG_MPSAFE, &tcp_lro_cpu_set_thresh, 0,
 121     "Number of interrupts in a row on the same CPU that will make us declare an 'affinity' cpu?");
 122
 123 static uint32_t tcp_less_accurate_lro_ts = 0;
 124 SYSCTL_UINT(_net_inet_tcp_lro, OID_AUTO, lro_less_accurate,
 125     CTLFLAG_MPSAFE, &tcp_less_accurate_lro_ts, 0,
 126     "Do we trade off efficency by doing less timestamp operations for time accuracy?");
 127
 128 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, fullqueue, CTLFLAG_RD,
 129     &tcp_inp_lro_direct_queue, "Number of lro's fully queued to transport");
 130 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, wokeup, CTLFLAG_RD,
 131     &tcp_inp_lro_wokeup_queue, "Number of lro's where we woke up transport via hpts");
 132 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, compressed, CTLFLAG_RD,
 133     &tcp_inp_lro_compressed, "Number of lro's compressed and sent to transport");
 134 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, lockcnt, CTLFLAG_RD,
 135     &tcp_inp_lro_locks_taken, "Number of lro's inp_wlocks taken");
 136 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, extra_mbuf, CTLFLAG_RD,
 137     &tcp_extra_mbuf, "Number of times we had an extra compressed ack dropped into the tp");
 138 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, would_have_but, CTLFLAG_RD,
 139     &tcp_would_have_but, "Number of times we would have had an extra compressed, but mget failed");
 140 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, with_m_ackcmp, CTLFLAG_RD,
 141     &tcp_comp_total, "Number of mbufs queued with M_ACKCMP flags set");
 142 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, without_m_ackcmp, CTLFLAG_RD,
 143     &tcp_uncomp_total, "Number of mbufs queued without M_ACKCMP");
 144 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, lro_badcsum, CTLFLAG_RD,
 145     &tcp_bad_csums, "Number of packets that the common code saw with bad csums");
 146
 147 void
 148 tcp_lro_reg_mbufq(void)
 149 {
 150         atomic_fetchadd_long(&tcplro_stacks_wanting_mbufq, 1);
 151 }
 152
 153 void
 154 tcp_lro_dereg_mbufq(void)
 155 {
 156         atomic_fetchadd_long(&tcplro_stacks_wanting_mbufq, -1);
 157 }
 158
 159 static __inline void
 160 tcp_lro_active_insert(struct lro_ctrl *lc, struct lro_head *bucket,
 161     struct lro_entry *le)
 162 {
 163
 164         LIST_INSERT_HEAD(&lc->lro_active, le, next);
 165         LIST_INSERT_HEAD(bucket, le, hash_next);
 166 }
 167
 168 static __inline void
 169 tcp_lro_active_remove(struct lro_entry *le)
 170 {
 171
 172         LIST_REMOVE(le, next);          /* active list */
 173         LIST_REMOVE(le, hash_next);     /* hash bucket */
 174 }
 175
 176 int
 177 tcp_lro_init(struct lro_ctrl *lc)
 178 {
 179         return (tcp_lro_init_args(lc, NULL, tcp_lro_entries, 0));
 180 }
 181
 182 int
 183 tcp_lro_init_args(struct lro_ctrl *lc, struct ifnet *ifp,
 184     unsigned lro_entries, unsigned lro_mbufs)
 185 {
 186         struct lro_entry *le;
 187         size_t size;
 188         unsigned i, elements;
 189
 190         lc->lro_bad_csum = 0;
 191         lc->lro_queued = 0;
 192         lc->lro_flushed = 0;
 193         lc->lro_mbuf_count = 0;
 194         lc->lro_mbuf_max = lro_mbufs;
 195         lc->lro_cnt = lro_entries;
 196         lc->lro_ackcnt_lim = TCP_LRO_ACKCNT_MAX;
 197         lc->lro_length_lim = TCP_LRO_LENGTH_MAX;
 198         lc->ifp = ifp;
 199         LIST_INIT(&lc->lro_free);
 200         LIST_INIT(&lc->lro_active);
 201
 202         /* create hash table to accelerate entry lookup */
 203         if (lro_entries > lro_mbufs)
 204                 elements = lro_entries;
 205         else
 206                 elements = lro_mbufs;
 207         lc->lro_hash = phashinit_flags(elements, M_LRO, &lc->lro_hashsz,
 208             HASH_NOWAIT);
 209         if (lc->lro_hash == NULL) {
 210                 memset(lc, 0, sizeof(*lc));
 211                 return (ENOMEM);
 212         }
 213
 214         /* compute size to allocate */
 215         size = (lro_mbufs * sizeof(struct lro_mbuf_sort)) +
 216             (lro_entries * sizeof(*le));
 217         lc->lro_mbuf_data = (struct lro_mbuf_sort *)
 218             malloc(size, M_LRO, M_NOWAIT | M_ZERO);
 219
 220         /* check for out of memory */
 221         if (lc->lro_mbuf_data == NULL) {
 222                 free(lc->lro_hash, M_LRO);
 223                 memset(lc, 0, sizeof(*lc));
 224                 return (ENOMEM);
 225         }
 226         /* compute offset for LRO entries */
 227         le = (struct lro_entry *)
 228             (lc->lro_mbuf_data + lro_mbufs);
 229
 230         /* setup linked list */
 231         for (i = 0; i != lro_entries; i++)
 232                 LIST_INSERT_HEAD(&lc->lro_free, le + i, next);
 233
 234         return (0);
 235 }
 236
 237 struct vxlan_header {
 238         uint32_t        vxlh_flags;
 239         uint32_t        vxlh_vni;
 240 };
 241
 242 static inline void *
 243 tcp_lro_low_level_parser(void *ptr, struct lro_parser *parser, bool update_data, bool is_vxlan, int mlen)
 244 {
 245         const struct ether_vlan_header *eh;
 246         void *old;
 247         uint16_t eth_type;
 248
 249         if (update_data)
 250                 memset(parser, 0, sizeof(*parser));
 251
 252         old = ptr;
 253
 254         if (is_vxlan) {
 255                 const struct vxlan_header *vxh;
 256                 vxh = ptr;
 257                 ptr = (uint8_t *)ptr + sizeof(*vxh);
 258                 if (update_data) {
 259                         parser->data.vxlan_vni =
 260                             vxh->vxlh_vni & htonl(0xffffff00);
 261                 }
 262         }
 263
 264         eh = ptr;
 265         if (__predict_false(eh->evl_encap_proto == htons(ETHERTYPE_VLAN))) {
 266                 eth_type = eh->evl_proto;
 267                 if (update_data) {
 268                         /* strip priority and keep VLAN ID only */
 269                         parser->data.vlan_id = eh->evl_tag & htons(EVL_VLID_MASK);
 270                 }
 271                 /* advance to next header */
 272                 ptr = (uint8_t *)ptr + ETHER_HDR_LEN + ETHER_VLAN_ENCAP_LEN;
 273                 mlen -= (ETHER_HDR_LEN  + ETHER_VLAN_ENCAP_LEN);
 274         } else {
 275                 eth_type = eh->evl_encap_proto;
 276                 /* advance to next header */
 277                 mlen -= ETHER_HDR_LEN;
 278                 ptr = (uint8_t *)ptr + ETHER_HDR_LEN;
 279         }
 280         if (__predict_false(mlen <= 0))
 281                 return (NULL);
 282         switch (eth_type) {
 283 #ifdef INET
 284         case htons(ETHERTYPE_IP):
 285                 parser->ip4 = ptr;
 286                 if (__predict_false(mlen < sizeof(struct ip)))
 287                         return (NULL);
 288                 /* Ensure there are no IPv4 options. */
 289                 if ((parser->ip4->ip_hl << 2) != sizeof (*parser->ip4))
 290                         break;
 291                 /* .. and the packet is not fragmented. */
 292                 if (parser->ip4->ip_off & htons(IP_MF|IP_OFFMASK))
 293                         break;
 294                 ptr = (uint8_t *)ptr + (parser->ip4->ip_hl << 2);
 295                 mlen -= sizeof(struct ip);
 296                 if (update_data) {
 297                         parser->data.s_addr.v4 = parser->ip4->ip_src;
 298                         parser->data.d_addr.v4 = parser->ip4->ip_dst;
 299                 }
 300                 switch (parser->ip4->ip_p) {
 301                 case IPPROTO_UDP:
 302                         if (__predict_false(mlen < sizeof(struct udphdr)))
 303                                 return (NULL);
 304                         parser->udp = ptr;
 305                         if (update_data) {
 306                                 parser->data.lro_type = LRO_TYPE_IPV4_UDP;
 307                                 parser->data.s_port = parser->udp->uh_sport;
 308                                 parser->data.d_port = parser->udp->uh_dport;
 309                         } else {
 310                                 MPASS(parser->data.lro_type == LRO_TYPE_IPV4_UDP);
 311                         }
 312                         ptr = ((uint8_t *)ptr + sizeof(*parser->udp));
 313                         parser->total_hdr_len = (uint8_t *)ptr - (uint8_t *)old;
 314                         return (ptr);
 315                 case IPPROTO_TCP:
 316                         parser->tcp = ptr;
 317                         if (__predict_false(mlen < sizeof(struct tcphdr)))
 318                                 return (NULL);
 319                         if (update_data) {
 320                                 parser->data.lro_type = LRO_TYPE_IPV4_TCP;
 321                                 parser->data.s_port = parser->tcp->th_sport;
 322                                 parser->data.d_port = parser->tcp->th_dport;
 323                         } else {
 324                                 MPASS(parser->data.lro_type == LRO_TYPE_IPV4_TCP);
 325                         }
 326                         if (__predict_false(mlen < (parser->tcp->th_off << 2)))
 327                                 return (NULL);
 328                         ptr = (uint8_t *)ptr + (parser->tcp->th_off << 2);
 329                         parser->total_hdr_len = (uint8_t *)ptr - (uint8_t *)old;
 330                         return (ptr);
 331                 default:
 332                         break;
 333                 }
 334                 break;
 335 #endif
 336 #ifdef INET6
 337         case htons(ETHERTYPE_IPV6):
 338                 parser->ip6 = ptr;
 339                 if (__predict_false(mlen < sizeof(struct ip6_hdr)))
 340                         return (NULL);
 341                 ptr = (uint8_t *)ptr + sizeof(*parser->ip6);
 342                 if (update_data) {
 343                         parser->data.s_addr.v6 = parser->ip6->ip6_src;
 344                         parser->data.d_addr.v6 = parser->ip6->ip6_dst;
 345                 }
 346                 mlen -= sizeof(struct ip6_hdr);
 347                 switch (parser->ip6->ip6_nxt) {
 348                 case IPPROTO_UDP:
 349                         if (__predict_false(mlen < sizeof(struct udphdr)))
 350                                 return (NULL);
 351                         parser->udp = ptr;
 352                         if (update_data) {
 353                                 parser->data.lro_type = LRO_TYPE_IPV6_UDP;
 354                                 parser->data.s_port = parser->udp->uh_sport;
 355                                 parser->data.d_port = parser->udp->uh_dport;
 356                         } else {
 357                                 MPASS(parser->data.lro_type == LRO_TYPE_IPV6_UDP);
 358                         }
 359                         ptr = (uint8_t *)ptr + sizeof(*parser->udp);
 360                         parser->total_hdr_len = (uint8_t *)ptr - (uint8_t *)old;
 361                         return (ptr);
 362                 case IPPROTO_TCP:
 363                         if (__predict_false(mlen < sizeof(struct tcphdr)))
 364                                 return (NULL);
 365                         parser->tcp = ptr;
 366                         if (update_data) {
 367                                 parser->data.lro_type = LRO_TYPE_IPV6_TCP;
 368                                 parser->data.s_port = parser->tcp->th_sport;
 369                                 parser->data.d_port = parser->tcp->th_dport;
 370                         } else {
 371                                 MPASS(parser->data.lro_type == LRO_TYPE_IPV6_TCP);
 372                         }
 373                         if (__predict_false(mlen < (parser->tcp->th_off << 2)))
 374                                 return (NULL);
 375                         ptr = (uint8_t *)ptr + (parser->tcp->th_off << 2);
 376                         parser->total_hdr_len = (uint8_t *)ptr - (uint8_t *)old;
 377                         return (ptr);
 378                 default:
 379                         break;
 380                 }
 381                 break;
 382 #endif
 383         default:
 384                 break;
 385         }
 386         /* Invalid packet - cannot parse */
 387         return (NULL);
 388 }
 389
 390 static const int vxlan_csum = CSUM_INNER_L3_CALC | CSUM_INNER_L3_VALID |
 391     CSUM_INNER_L4_CALC | CSUM_INNER_L4_VALID;
 392
 393 static inline struct lro_parser *
 394 tcp_lro_parser(struct mbuf *m, struct lro_parser *po, struct lro_parser *pi, bool update_data)
 395 {
 396         void *data_ptr;
 397
 398         /* Try to parse outer headers first. */
 399         data_ptr = tcp_lro_low_level_parser(m->m_data, po, update_data, false, m->m_len);
 400         if (data_ptr == NULL || po->total_hdr_len > m->m_len)
 401                 return (NULL);
 402
 403         if (update_data) {
 404                 /* Store VLAN ID, if any. */
 405                 if (__predict_false(m->m_flags & M_VLANTAG)) {
 406                         po->data.vlan_id =
 407                             htons(m->m_pkthdr.ether_vtag) & htons(EVL_VLID_MASK);
 408                 }
 409                 /* Store decrypted flag, if any. */
 410                 if (__predict_false((m->m_pkthdr.csum_flags &
 411                     CSUM_TLS_MASK) == CSUM_TLS_DECRYPTED))
 412                         po->data.lro_flags |= LRO_FLAG_DECRYPTED;
 413         }
 414
 415         switch (po->data.lro_type) {
 416         case LRO_TYPE_IPV4_UDP:
 417         case LRO_TYPE_IPV6_UDP:
 418                 /* Check for VXLAN headers. */
 419                 if ((m->m_pkthdr.csum_flags & vxlan_csum) != vxlan_csum)
 420                         break;
 421
 422                 /* Try to parse inner headers. */
 423                 data_ptr = tcp_lro_low_level_parser(data_ptr, pi, update_data, true,
 424                                                     (m->m_len - ((caddr_t)data_ptr - m->m_data)));
 425                 if (data_ptr == NULL || (pi->total_hdr_len + po->total_hdr_len) > m->m_len)
 426                         break;
 427
 428                 /* Verify supported header types. */
 429                 switch (pi->data.lro_type) {
 430                 case LRO_TYPE_IPV4_TCP:
 431                 case LRO_TYPE_IPV6_TCP:
 432                         return (pi);
 433                 default:
 434                         break;
 435                 }
 436                 break;
 437         case LRO_TYPE_IPV4_TCP:
 438         case LRO_TYPE_IPV6_TCP:
 439                 if (update_data)
 440                         memset(pi, 0, sizeof(*pi));
 441                 return (po);
 442         default:
 443                 break;
 444         }
 445         return (NULL);
 446 }
 447
 448 static inline int
 449 tcp_lro_trim_mbuf_chain(struct mbuf *m, const struct lro_parser *po)
 450 {
 451         int len;
 452
 453         switch (po->data.lro_type) {
 454 #ifdef INET
 455         case LRO_TYPE_IPV4_TCP:
 456                 len = ((uint8_t *)po->ip4 - (uint8_t *)m->m_data) +
 457                     ntohs(po->ip4->ip_len);
 458                 break;
 459 #endif
 460 #ifdef INET6
 461         case LRO_TYPE_IPV6_TCP:
 462                 len = ((uint8_t *)po->ip6 - (uint8_t *)m->m_data) +
 463                     ntohs(po->ip6->ip6_plen) + sizeof(*po->ip6);
 464                 break;
 465 #endif
 466         default:
 467                 return (TCP_LRO_CANNOT);
 468         }
 469
 470         /*
 471          * If the frame is padded beyond the end of the IP packet,
 472          * then trim the extra bytes off:
 473          */
 474         if (__predict_true(m->m_pkthdr.len == len)) {
 475                 return (0);
 476         } else if (m->m_pkthdr.len > len) {
 477                 m_adj(m, len - m->m_pkthdr.len);
 478                 return (0);
 479         }
 480         return (TCP_LRO_CANNOT);
 481 }
 482
 483 static struct tcphdr *
 484 tcp_lro_get_th(struct mbuf *m)
 485 {
 486         return ((struct tcphdr *)((uint8_t *)m->m_data + m->m_pkthdr.lro_tcp_h_off));
 487 }
 488
 489 static void
 490 lro_free_mbuf_chain(struct mbuf *m)
 491 {
 492         struct mbuf *save;
 493
 494         while (m) {
 495                 save = m->m_nextpkt;
 496                 m->m_nextpkt = NULL;
 497                 m_freem(m);
 498                 m = save;
 499         }
 500 }
 501
 502 void
 503 tcp_lro_free(struct lro_ctrl *lc)
 504 {
 505         struct lro_entry *le;
 506         unsigned x;
 507
 508         /* reset LRO free list */
 509         LIST_INIT(&lc->lro_free);
 510
 511         /* free active mbufs, if any */
 512         while ((le = LIST_FIRST(&lc->lro_active)) != NULL) {
 513                 tcp_lro_active_remove(le);
 514                 lro_free_mbuf_chain(le->m_head);
 515         }
 516
 517         /* free hash table */
 518         free(lc->lro_hash, M_LRO);
 519         lc->lro_hash = NULL;
 520         lc->lro_hashsz = 0;
 521
 522         /* free mbuf array, if any */
 523         for (x = 0; x != lc->lro_mbuf_count; x++)
 524                 m_freem(lc->lro_mbuf_data[x].mb);
 525         lc->lro_mbuf_count = 0;
 526
 527         /* free allocated memory, if any */
 528         free(lc->lro_mbuf_data, M_LRO);
 529         lc->lro_mbuf_data = NULL;
 530 }
 531
 532 static uint16_t
 533 tcp_lro_rx_csum_tcphdr(const struct tcphdr *th)
 534 {
 535         const uint16_t *ptr;
 536         uint32_t csum;
 537         uint16_t len;
 538
 539         csum = -th->th_sum;     /* exclude checksum field */
 540         len = th->th_off;
 541         ptr = (const uint16_t *)th;
 542         while (len--) {
 543                 csum += *ptr;
 544                 ptr++;
 545                 csum += *ptr;
 546                 ptr++;
 547         }
 548         while (csum > 0xffff)
 549                 csum = (csum >> 16) + (csum & 0xffff);
 550
 551         return (csum);
 552 }
 553
 554 static uint16_t
 555 tcp_lro_rx_csum_data(const struct lro_parser *pa, uint16_t tcp_csum)
 556 {
 557         uint32_t c;
 558         uint16_t cs;
 559
 560         c = tcp_csum;
 561
 562         switch (pa->data.lro_type) {
 563 #ifdef INET6
 564         case LRO_TYPE_IPV6_TCP:
 565                 /* Compute full pseudo IPv6 header checksum. */
 566                 cs = in6_cksum_pseudo(pa->ip6, ntohs(pa->ip6->ip6_plen), pa->ip6->ip6_nxt, 0);
 567                 break;
 568 #endif
 569 #ifdef INET
 570         case LRO_TYPE_IPV4_TCP:
 571                 /* Compute full pseudo IPv4 header checsum. */
 572                 cs = in_addword(ntohs(pa->ip4->ip_len) - sizeof(*pa->ip4), IPPROTO_TCP);
 573                 cs = in_pseudo(pa->ip4->ip_src.s_addr, pa->ip4->ip_dst.s_addr, htons(cs));
 574                 break;
 575 #endif
 576         default:
 577                 cs = 0;         /* Keep compiler happy. */
 578                 break;
 579         }
 580
 581         /* Complement checksum. */
 582         cs = ~cs;
 583         c += cs;
 584
 585         /* Remove TCP header checksum. */
 586         cs = ~tcp_lro_rx_csum_tcphdr(pa->tcp);
 587         c += cs;
 588
 589         /* Compute checksum remainder. */
 590         while (c > 0xffff)
 591                 c = (c >> 16) + (c & 0xffff);
 592
 593         return (c);
 594 }
 595
 596 static void
 597 tcp_lro_rx_done(struct lro_ctrl *lc)
 598 {
 599         struct lro_entry *le;
 600
 601         while ((le = LIST_FIRST(&lc->lro_active)) != NULL) {
 602                 tcp_lro_active_remove(le);
 603                 tcp_lro_flush(lc, le);
 604         }
 605 }
 606
 607 static void
 608 tcp_lro_flush_active(struct lro_ctrl *lc)
 609 {
 610         struct lro_entry *le;
 611
 612         /*
 613          * Walk through the list of le entries, and
 614          * any one that does have packets flush. This
 615          * is called because we have an inbound packet
 616          * (e.g. SYN) that has to have all others flushed
 617          * in front of it. Note we have to do the remove
 618          * because tcp_lro_flush() assumes that the entry
 619          * is being freed. This is ok it will just get
 620          * reallocated again like it was new.
 621          */
 622         LIST_FOREACH(le, &lc->lro_active, next) {
 623                 if (le->m_head != NULL) {
 624                         tcp_lro_active_remove(le);
 625                         tcp_lro_flush(lc, le);
 626                 }
 627         }
 628 }
 629
 630 void
 631 tcp_lro_flush_inactive(struct lro_ctrl *lc, const struct timeval *timeout)
 632 {
 633         struct lro_entry *le, *le_tmp;
 634         uint64_t now, tov;
 635         struct bintime bt;
 636
 637         NET_EPOCH_ASSERT();
 638         if (LIST_EMPTY(&lc->lro_active))
 639                 return;
 640
 641         /* get timeout time and current time in ns */
 642         binuptime(&bt);
 643         now = bintime2ns(&bt);
 644         tov = ((timeout->tv_sec * 1000000000) + (timeout->tv_usec * 1000));
 645         LIST_FOREACH_SAFE(le, &lc->lro_active, next, le_tmp) {
 646                 if (now >= (bintime2ns(&le->alloc_time) + tov)) {
 647                         tcp_lro_active_remove(le);
 648                         tcp_lro_flush(lc, le);
 649                 }
 650         }
 651 }
 652
 653 #ifdef INET
 654 static int
 655 tcp_lro_rx_ipv4(struct lro_ctrl *lc, struct mbuf *m, struct ip *ip4)
 656 {
 657         uint16_t csum;
 658
 659         /* Legacy IP has a header checksum that needs to be correct. */
 660         if (m->m_pkthdr.csum_flags & CSUM_IP_CHECKED) {
 661                 if (__predict_false((m->m_pkthdr.csum_flags & CSUM_IP_VALID) == 0)) {
 662                         lc->lro_bad_csum++;
 663                         return (TCP_LRO_CANNOT);
 664                 }
 665         } else {
 666                 csum = in_cksum_hdr(ip4);
 667                 if (__predict_false(csum != 0)) {
 668                         lc->lro_bad_csum++;
 669                         return (TCP_LRO_CANNOT);
 670                 }
 671         }
 672         return (0);
 673 }
 674 #endif
 675
 676 #ifdef TCPHPTS
 677 static void
 678 tcp_lro_log(struct tcpcb *tp, const struct lro_ctrl *lc,
 679     const struct lro_entry *le, const struct mbuf *m,
 680     int frm, int32_t tcp_data_len, uint32_t th_seq,
 681     uint32_t th_ack, uint16_t th_win)
 682 {
 683         if (tp->t_logstate != TCP_LOG_STATE_OFF) {
 684                 union tcp_log_stackspecific log;
 685                 struct timeval tv, btv;
 686                 uint32_t cts;
 687
 688                 cts = tcp_get_usecs(&tv);
 689                 memset(&log, 0, sizeof(union tcp_log_stackspecific));
 690                 log.u_bbr.flex8 = frm;
 691                 log.u_bbr.flex1 = tcp_data_len;
 692                 if (m)
 693                         log.u_bbr.flex2 = m->m_pkthdr.len;
 694                 else
 695                         log.u_bbr.flex2 = 0;
 696                 if (le->m_head) {
 697                         log.u_bbr.flex3 = le->m_head->m_pkthdr.lro_nsegs;
 698                         log.u_bbr.flex4 = le->m_head->m_pkthdr.lro_tcp_d_len;
 699                         log.u_bbr.flex5 = le->m_head->m_pkthdr.len;
 700                         log.u_bbr.delRate = le->m_head->m_flags;
 701                         log.u_bbr.rttProp = le->m_head->m_pkthdr.rcv_tstmp;
 702                 }
 703                 log.u_bbr.inflight = th_seq;
 704                 log.u_bbr.delivered = th_ack;
 705                 log.u_bbr.timeStamp = cts;
 706                 log.u_bbr.epoch = le->next_seq;
 707                 log.u_bbr.lt_epoch = le->ack_seq;
 708                 log.u_bbr.pacing_gain = th_win;
 709                 log.u_bbr.cwnd_gain = le->window;
 710                 log.u_bbr.lost = curcpu;
 711                 log.u_bbr.cur_del_rate = (uintptr_t)m;
 712                 log.u_bbr.bw_inuse = (uintptr_t)le->m_head;
 713                 bintime2timeval(&lc->lro_last_queue_time, &btv);
 714                 log.u_bbr.flex6 = tcp_tv_to_usectick(&btv);
 715                 log.u_bbr.flex7 = le->compressed;
 716                 log.u_bbr.pacing_gain = le->uncompressed;
 717                 if (in_epoch(net_epoch_preempt))
 718                         log.u_bbr.inhpts = 1;
 719                 else
 720                         log.u_bbr.inhpts = 0;
 721                 TCP_LOG_EVENTP(tp, NULL, &tptosocket(tp)->so_rcv,
 722                     &tptosocket(tp)->so_snd,
 723                     TCP_LOG_LRO, 0, 0, &log, false, &tv);
 724         }
 725 }
 726 #endif
 727
 728 static inline void
 729 tcp_lro_assign_and_checksum_16(uint16_t *ptr, uint16_t value, uint16_t *psum)
 730 {
 731         uint32_t csum;
 732
 733         csum = 0xffff - *ptr + value;
 734         while (csum > 0xffff)
 735                 csum = (csum >> 16) + (csum & 0xffff);
 736         *ptr = value;
 737         *psum = csum;
 738 }
 739
 740 static uint16_t
 741 tcp_lro_update_checksum(const struct lro_parser *pa, const struct lro_entry *le,
 742     uint16_t payload_len, uint16_t delta_sum)
 743 {
 744         uint32_t csum;
 745         uint16_t tlen;
 746         uint16_t temp[5] = {};
 747
 748         switch (pa->data.lro_type) {
 749         case LRO_TYPE_IPV4_TCP:
 750                 /* Compute new IPv4 length. */
 751                 tlen = (pa->ip4->ip_hl << 2) + (pa->tcp->th_off << 2) + payload_len;
 752                 tcp_lro_assign_and_checksum_16(&pa->ip4->ip_len, htons(tlen), &temp[0]);
 753
 754                 /* Subtract delta from current IPv4 checksum. */
 755                 csum = pa->ip4->ip_sum + 0xffff - temp[0];
 756                 while (csum > 0xffff)
 757                         csum = (csum >> 16) + (csum & 0xffff);
 758                 tcp_lro_assign_and_checksum_16(&pa->ip4->ip_sum, csum, &temp[1]);
 759                 goto update_tcp_header;
 760
 761         case LRO_TYPE_IPV6_TCP:
 762                 /* Compute new IPv6 length. */
 763                 tlen = (pa->tcp->th_off << 2) + payload_len;
 764                 tcp_lro_assign_and_checksum_16(&pa->ip6->ip6_plen, htons(tlen), &temp[0]);
 765                 goto update_tcp_header;
 766
 767         case LRO_TYPE_IPV4_UDP:
 768                 /* Compute new IPv4 length. */
 769                 tlen = (pa->ip4->ip_hl << 2) + sizeof(*pa->udp) + payload_len;
 770                 tcp_lro_assign_and_checksum_16(&pa->ip4->ip_len, htons(tlen), &temp[0]);
 771
 772                 /* Subtract delta from current IPv4 checksum. */
 773                 csum = pa->ip4->ip_sum + 0xffff - temp[0];
 774                 while (csum > 0xffff)
 775                         csum = (csum >> 16) + (csum & 0xffff);
 776                 tcp_lro_assign_and_checksum_16(&pa->ip4->ip_sum, csum, &temp[1]);
 777                 goto update_udp_header;
 778
 779         case LRO_TYPE_IPV6_UDP:
 780                 /* Compute new IPv6 length. */
 781                 tlen = sizeof(*pa->udp) + payload_len;
 782                 tcp_lro_assign_and_checksum_16(&pa->ip6->ip6_plen, htons(tlen), &temp[0]);
 783                 goto update_udp_header;
 784
 785         default:
 786                 return (0);
 787         }
 788
 789 update_tcp_header:
 790         /* Compute current TCP header checksum. */
 791         temp[2] = tcp_lro_rx_csum_tcphdr(pa->tcp);
 792
 793         /* Incorporate the latest ACK into the TCP header. */
 794         pa->tcp->th_ack = le->ack_seq;
 795         pa->tcp->th_win = le->window;
 796
 797         /* Incorporate latest timestamp into the TCP header. */
 798         if (le->timestamp != 0) {
 799                 uint32_t *ts_ptr;
 800
 801                 ts_ptr = (uint32_t *)(pa->tcp + 1);
 802                 ts_ptr[1] = htonl(le->tsval);
 803                 ts_ptr[2] = le->tsecr;
 804         }
 805
 806         /* Compute new TCP header checksum. */
 807         temp[3] = tcp_lro_rx_csum_tcphdr(pa->tcp);
 808
 809         /* Compute new TCP checksum. */
 810         csum = pa->tcp->th_sum + 0xffff - delta_sum +
 811             0xffff - temp[0] + 0xffff - temp[3] + temp[2];
 812         while (csum > 0xffff)
 813                 csum = (csum >> 16) + (csum & 0xffff);
 814
 815         /* Assign new TCP checksum. */
 816         tcp_lro_assign_and_checksum_16(&pa->tcp->th_sum, csum, &temp[4]);
 817
 818         /* Compute all modififications affecting next checksum. */
 819         csum = temp[0] + temp[1] + 0xffff - temp[2] +
 820             temp[3] + temp[4] + delta_sum;
 821         while (csum > 0xffff)
 822                 csum = (csum >> 16) + (csum & 0xffff);
 823
 824         /* Return delta checksum to next stage, if any. */
 825         return (csum);
 826
 827 update_udp_header:
 828         tlen = sizeof(*pa->udp) + payload_len;
 829         /* Assign new UDP length and compute checksum delta. */
 830         tcp_lro_assign_and_checksum_16(&pa->udp->uh_ulen, htons(tlen), &temp[2]);
 831
 832         /* Check if there is a UDP checksum. */
 833         if (__predict_false(pa->udp->uh_sum != 0)) {
 834                 /* Compute new UDP checksum. */
 835                 csum = pa->udp->uh_sum + 0xffff - delta_sum +
 836                     0xffff - temp[0] + 0xffff - temp[2];
 837                 while (csum > 0xffff)
 838                         csum = (csum >> 16) + (csum & 0xffff);
 839                 /* Assign new UDP checksum. */
 840                 tcp_lro_assign_and_checksum_16(&pa->udp->uh_sum, csum, &temp[3]);
 841         }
 842
 843         /* Compute all modififications affecting next checksum. */
 844         csum = temp[0] + temp[1] + temp[2] + temp[3] + delta_sum;
 845         while (csum > 0xffff)
 846                 csum = (csum >> 16) + (csum & 0xffff);
 847
 848         /* Return delta checksum to next stage, if any. */
 849         return (csum);
 850 }
 851
 852 static void
 853 tcp_flush_out_entry(struct lro_ctrl *lc, struct lro_entry *le)
 854 {
 855         /* Check if we need to recompute any checksums. */
 856         if (le->needs_merge) {
 857                 uint16_t csum;
 858
 859                 switch (le->inner.data.lro_type) {
 860                 case LRO_TYPE_IPV4_TCP:
 861                         csum = tcp_lro_update_checksum(&le->inner, le,
 862                             le->m_head->m_pkthdr.lro_tcp_d_len,
 863                             le->m_head->m_pkthdr.lro_tcp_d_csum);
 864                         csum = tcp_lro_update_checksum(&le->outer, NULL,
 865                             le->m_head->m_pkthdr.lro_tcp_d_len +
 866                             le->inner.total_hdr_len, csum);
 867                         le->m_head->m_pkthdr.csum_flags = CSUM_DATA_VALID |
 868                             CSUM_PSEUDO_HDR | CSUM_IP_CHECKED | CSUM_IP_VALID;
 869                         le->m_head->m_pkthdr.csum_data = 0xffff;
 870                         if (__predict_false(le->outer.data.lro_flags & LRO_FLAG_DECRYPTED))
 871                                 le->m_head->m_pkthdr.csum_flags |= CSUM_TLS_DECRYPTED;
 872                         break;
 873                 case LRO_TYPE_IPV6_TCP:
 874                         csum = tcp_lro_update_checksum(&le->inner, le,
 875                             le->m_head->m_pkthdr.lro_tcp_d_len,
 876                             le->m_head->m_pkthdr.lro_tcp_d_csum);
 877                         csum = tcp_lro_update_checksum(&le->outer, NULL,
 878                             le->m_head->m_pkthdr.lro_tcp_d_len +
 879                             le->inner.total_hdr_len, csum);
 880                         le->m_head->m_pkthdr.csum_flags = CSUM_DATA_VALID |
 881                             CSUM_PSEUDO_HDR;
 882                         le->m_head->m_pkthdr.csum_data = 0xffff;
 883                         if (__predict_false(le->outer.data.lro_flags & LRO_FLAG_DECRYPTED))
 884                                 le->m_head->m_pkthdr.csum_flags |= CSUM_TLS_DECRYPTED;
 885                         break;
 886                 case LRO_TYPE_NONE:
 887                         switch (le->outer.data.lro_type) {
 888                         case LRO_TYPE_IPV4_TCP:
 889                                 csum = tcp_lro_update_checksum(&le->outer, le,
 890                                     le->m_head->m_pkthdr.lro_tcp_d_len,
 891                                     le->m_head->m_pkthdr.lro_tcp_d_csum);
 892                                 le->m_head->m_pkthdr.csum_flags = CSUM_DATA_VALID |
 893                                     CSUM_PSEUDO_HDR | CSUM_IP_CHECKED | CSUM_IP_VALID;
 894                                 le->m_head->m_pkthdr.csum_data = 0xffff;
 895                                 if (__predict_false(le->outer.data.lro_flags & LRO_FLAG_DECRYPTED))
 896                                         le->m_head->m_pkthdr.csum_flags |= CSUM_TLS_DECRYPTED;
 897                                 break;
 898                         case LRO_TYPE_IPV6_TCP:
 899                                 csum = tcp_lro_update_checksum(&le->outer, le,
 900                                     le->m_head->m_pkthdr.lro_tcp_d_len,
 901                                     le->m_head->m_pkthdr.lro_tcp_d_csum);
 902                                 le->m_head->m_pkthdr.csum_flags = CSUM_DATA_VALID |
 903                                     CSUM_PSEUDO_HDR;
 904                                 le->m_head->m_pkthdr.csum_data = 0xffff;
 905                                 if (__predict_false(le->outer.data.lro_flags & LRO_FLAG_DECRYPTED))
 906                                         le->m_head->m_pkthdr.csum_flags |= CSUM_TLS_DECRYPTED;
 907                                 break;
 908                         default:
 909                                 break;
 910                         }
 911                         break;
 912                 default:
 913                         break;
 914                 }
 915         }
 916
 917         /*
 918          * Break any chain, this is not set to NULL on the singleton
 919          * case m_nextpkt points to m_head. Other case set them
 920          * m_nextpkt to NULL in push_and_replace.
 921          */
 922         le->m_head->m_nextpkt = NULL;
 923         lc->lro_queued += le->m_head->m_pkthdr.lro_nsegs;
 924         (*lc->ifp->if_input)(lc->ifp, le->m_head);
 925 }
 926
 927 static void
 928 tcp_set_entry_to_mbuf(struct lro_ctrl *lc, struct lro_entry *le,
 929     struct mbuf *m, struct tcphdr *th)
 930 {
 931         uint32_t *ts_ptr;
 932         uint16_t tcp_data_len;
 933         uint16_t tcp_opt_len;
 934
 935         ts_ptr = (uint32_t *)(th + 1);
 936         tcp_opt_len = (th->th_off << 2);
 937         tcp_opt_len -= sizeof(*th);
 938
 939         /* Check if there is a timestamp option. */
 940         if (tcp_opt_len == 0 ||
 941             __predict_false(tcp_opt_len != TCPOLEN_TSTAMP_APPA ||
 942             *ts_ptr != TCP_LRO_TS_OPTION)) {
 943                 /* We failed to find the timestamp option. */
 944                 le->timestamp = 0;
 945         } else {
 946                 le->timestamp = 1;
 947                 le->tsval = ntohl(*(ts_ptr + 1));
 948                 le->tsecr = *(ts_ptr + 2);
 949         }
 950
 951         tcp_data_len = m->m_pkthdr.lro_tcp_d_len;
 952
 953         /* Pull out TCP sequence numbers and window size. */
 954         le->next_seq = ntohl(th->th_seq) + tcp_data_len;
 955         le->ack_seq = th->th_ack;
 956         le->window = th->th_win;
 957         le->flags = tcp_get_flags(th);
 958         le->needs_merge = 0;
 959
 960         /* Setup new data pointers. */
 961         le->m_head = m;
 962         le->m_tail = m_last(m);
 963 }
 964
 965 static void
 966 tcp_push_and_replace(struct lro_ctrl *lc, struct lro_entry *le, struct mbuf *m)
 967 {
 968         struct lro_parser *pa;
 969
 970         /*
 971          * Push up the stack of the current entry
 972          * and replace it with "m".
 973          */
 974         struct mbuf *msave;
 975
 976         /* Grab off the next and save it */
 977         msave = le->m_head->m_nextpkt;
 978         le->m_head->m_nextpkt = NULL;
 979
 980         /* Now push out the old entry */
 981         tcp_flush_out_entry(lc, le);
 982
 983         /* Re-parse new header, should not fail. */
 984         pa = tcp_lro_parser(m, &le->outer, &le->inner, false);
 985         KASSERT(pa != NULL,
 986             ("tcp_push_and_replace: LRO parser failed on m=%p\n", m));
 987
 988         /*
 989          * Now to replace the data properly in the entry
 990          * we have to reset the TCP header and
 991          * other fields.
 992          */
 993         tcp_set_entry_to_mbuf(lc, le, m, pa->tcp);
 994
 995         /* Restore the next list */
 996         m->m_nextpkt = msave;
 997 }
 998
 999 static void
1000 tcp_lro_mbuf_append_pkthdr(struct lro_entry *le, const struct mbuf *p)
1001 {
1002         struct mbuf *m;
1003         uint32_t csum;
1004
1005         m = le->m_head;
1006         if (m->m_pkthdr.lro_nsegs == 1) {
1007                 /* Compute relative checksum. */
1008                 csum = p->m_pkthdr.lro_tcp_d_csum;
1009         } else {
1010                 /* Merge TCP data checksums. */
1011                 csum = (uint32_t)m->m_pkthdr.lro_tcp_d_csum +
1012                     (uint32_t)p->m_pkthdr.lro_tcp_d_csum;
1013                 while (csum > 0xffff)
1014                         csum = (csum >> 16) + (csum & 0xffff);
1015         }
1016
1017         /* Update various counters. */
1018         m->m_pkthdr.len += p->m_pkthdr.lro_tcp_d_len;
1019         m->m_pkthdr.lro_tcp_d_csum = csum;
1020         m->m_pkthdr.lro_tcp_d_len += p->m_pkthdr.lro_tcp_d_len;
1021         m->m_pkthdr.lro_nsegs += p->m_pkthdr.lro_nsegs;
1022         le->needs_merge = 1;
1023 }
1024
1025 static void
1026 tcp_lro_condense(struct lro_ctrl *lc, struct lro_entry *le)
1027 {
1028         /*
1029          * Walk through the mbuf chain we
1030          * have on tap and compress/condense
1031          * as required.
1032          */
1033         uint32_t *ts_ptr;
1034         struct mbuf *m;
1035         struct tcphdr *th;
1036         uint32_t tcp_data_len_total;
1037         uint32_t tcp_data_seg_total;
1038         uint16_t tcp_data_len;
1039         uint16_t tcp_opt_len;
1040
1041         /*
1042          * First we must check the lead (m_head)
1043          * we must make sure that it is *not*
1044          * something that should be sent up
1045          * right away (sack etc).
1046          */
1047 again:
1048         m = le->m_head->m_nextpkt;
1049         if (m == NULL) {
1050                 /* Just one left. */
1051                 return;
1052         }
1053
1054         th = tcp_lro_get_th(m);
1055         tcp_opt_len = (th->th_off << 2);
1056         tcp_opt_len -= sizeof(*th);
1057         ts_ptr = (uint32_t *)(th + 1);
1058
1059         if (tcp_opt_len != 0 && __predict_false(tcp_opt_len != TCPOLEN_TSTAMP_APPA ||
1060             *ts_ptr != TCP_LRO_TS_OPTION)) {
1061                 /*
1062                  * Its not the timestamp. We can't
1063                  * use this guy as the head.
1064                  */
1065                 le->m_head->m_nextpkt = m->m_nextpkt;
1066                 tcp_push_and_replace(lc, le, m);
1067                 goto again;
1068         }
1069         if ((tcp_get_flags(th) & ~(TH_ACK | TH_PUSH)) != 0) {
1070                 /*
1071                  * Make sure that previously seen segments/ACKs are delivered
1072                  * before this segment, e.g. FIN.
1073                  */
1074                 le->m_head->m_nextpkt = m->m_nextpkt;
1075                 tcp_push_and_replace(lc, le, m);
1076                 goto again;
1077         }
1078         while((m = le->m_head->m_nextpkt) != NULL) {
1079                 /*
1080                  * condense m into le, first
1081                  * pull m out of the list.
1082                  */
1083                 le->m_head->m_nextpkt = m->m_nextpkt;
1084                 m->m_nextpkt = NULL;
1085                 /* Setup my data */
1086                 tcp_data_len = m->m_pkthdr.lro_tcp_d_len;
1087                 th = tcp_lro_get_th(m);
1088                 ts_ptr = (uint32_t *)(th + 1);
1089                 tcp_opt_len = (th->th_off << 2);
1090                 tcp_opt_len -= sizeof(*th);
1091                 tcp_data_len_total = le->m_head->m_pkthdr.lro_tcp_d_len + tcp_data_len;
1092                 tcp_data_seg_total = le->m_head->m_pkthdr.lro_nsegs + m->m_pkthdr.lro_nsegs;
1093
1094                 if (tcp_data_seg_total >= lc->lro_ackcnt_lim ||
1095                     tcp_data_len_total >= lc->lro_length_lim) {
1096                         /* Flush now if appending will result in overflow. */
1097                         tcp_push_and_replace(lc, le, m);
1098                         goto again;
1099                 }
1100                 if (tcp_opt_len != 0 &&
1101                     __predict_false(tcp_opt_len != TCPOLEN_TSTAMP_APPA ||
1102                     *ts_ptr != TCP_LRO_TS_OPTION)) {
1103                         /*
1104                          * Maybe a sack in the new one? We need to
1105                          * start all over after flushing the
1106                          * current le. We will go up to the beginning
1107                          * and flush it (calling the replace again possibly
1108                          * or just returning).
1109                          */
1110                         tcp_push_and_replace(lc, le, m);
1111                         goto again;
1112                 }
1113                 if ((tcp_get_flags(th) & ~(TH_ACK | TH_PUSH)) != 0) {
1114                         tcp_push_and_replace(lc, le, m);
1115                         goto again;
1116                 }
1117                 if (tcp_opt_len != 0) {
1118                         uint32_t tsval = ntohl(*(ts_ptr + 1));
1119                         /* Make sure timestamp values are increasing. */
1120                         if (TSTMP_GT(le->tsval, tsval))  {
1121                                 tcp_push_and_replace(lc, le, m);
1122                                 goto again;
1123                         }
1124                         le->tsval = tsval;
1125                         le->tsecr = *(ts_ptr + 2);
1126                 }
1127                 /* Try to append the new segment. */
1128                 if (__predict_false(ntohl(th->th_seq) != le->next_seq ||
1129                                     ((tcp_get_flags(th) & TH_ACK) !=
1130                                       (le->flags & TH_ACK)) ||
1131                                     (tcp_data_len == 0 &&
1132                                      le->ack_seq == th->th_ack &&
1133                                      le->window == th->th_win))) {
1134                         /* Out of order packet, non-ACK + ACK or dup ACK. */
1135                         tcp_push_and_replace(lc, le, m);
1136                         goto again;
1137                 }
1138                 if (tcp_data_len != 0 ||
1139                     SEQ_GT(ntohl(th->th_ack), ntohl(le->ack_seq))) {
1140                         le->next_seq += tcp_data_len;
1141                         le->ack_seq = th->th_ack;
1142                         le->window = th->th_win;
1143                         le->needs_merge = 1;
1144                 } else if (th->th_ack == le->ack_seq) {
1145                         if (WIN_GT(th->th_win, le->window)) {
1146                                 le->window = th->th_win;
1147                                 le->needs_merge = 1;
1148                         }
1149                 }
1150
1151                 if (tcp_data_len == 0) {
1152                         m_freem(m);
1153                         continue;
1154                 }
1155
1156                 /* Merge TCP data checksum and length to head mbuf. */
1157                 tcp_lro_mbuf_append_pkthdr(le, m);
1158
1159                 /*
1160                  * Adjust the mbuf so that m_data points to the first byte of
1161                  * the ULP payload.  Adjust the mbuf to avoid complications and
1162                  * append new segment to existing mbuf chain.
1163                  */
1164                 m_adj(m, m->m_pkthdr.len - tcp_data_len);
1165                 m_demote_pkthdr(m);
1166                 le->m_tail->m_next = m;
1167                 le->m_tail = m_last(m);
1168         }
1169 }
1170
1171 #ifdef TCPHPTS
1172 static void
1173 tcp_queue_pkts(struct inpcb *inp, struct tcpcb *tp, struct lro_entry *le)
1174 {
1175         INP_WLOCK_ASSERT(inp);
1176         if (tp->t_in_pkt == NULL) {
1177                 /* Nothing yet there */
1178                 tp->t_in_pkt = le->m_head;
1179                 tp->t_tail_pkt = le->m_last_mbuf;
1180         } else {
1181                 /* Already some there */
1182                 tp->t_tail_pkt->m_nextpkt = le->m_head;
1183                 tp->t_tail_pkt = le->m_last_mbuf;
1184         }
1185         le->m_head = NULL;
1186         le->m_last_mbuf = NULL;
1187 }
1188
1189 static struct mbuf *
1190 tcp_lro_get_last_if_ackcmp(struct lro_ctrl *lc, struct lro_entry *le,
1191     struct inpcb *inp, int32_t *new_m, bool can_append_old_cmp)
1192 {
1193         struct tcpcb *tp;
1194         struct mbuf *m;
1195
1196         tp = intotcpcb(inp);
1197         if (__predict_false(tp == NULL))
1198                 return (NULL);
1199
1200         /* Look at the last mbuf if any in queue */
1201         if (can_append_old_cmp) {
1202                 m = tp->t_tail_pkt;
1203                 if (m != NULL && (m->m_flags & M_ACKCMP) != 0) {
1204                         if (M_TRAILINGSPACE(m) >= sizeof(struct tcp_ackent)) {
1205                                 tcp_lro_log(tp, lc, le, NULL, 23, 0, 0, 0, 0);
1206                                 *new_m = 0;
1207                                 counter_u64_add(tcp_extra_mbuf, 1);
1208                                 return (m);
1209                         } else {
1210                                 /* Mark we ran out of space */
1211                                 inp->inp_flags2 |= INP_MBUF_L_ACKS;
1212                         }
1213                 }
1214         }
1215         /* Decide mbuf size. */
1216         tcp_lro_log(tp, lc, le, NULL, 21, 0, 0, 0, 0);
1217         if (inp->inp_flags2 & INP_MBUF_L_ACKS)
1218                 m = m_getcl(M_NOWAIT, MT_DATA, M_ACKCMP | M_PKTHDR);
1219         else
1220                 m = m_gethdr(M_NOWAIT, MT_DATA);
1221
1222         if (__predict_false(m == NULL)) {
1223                 counter_u64_add(tcp_would_have_but, 1);
1224                 return (NULL);
1225         }
1226         counter_u64_add(tcp_comp_total, 1);
1227         m->m_pkthdr.rcvif = lc->ifp;
1228         m->m_flags |= M_ACKCMP;
1229         *new_m = 1;
1230         return (m);
1231 }
1232
1233 static struct inpcb *
1234 tcp_lro_lookup(struct ifnet *ifp, struct lro_parser *pa)
1235 {
1236         struct inpcb *inp;
1237
1238         switch (pa->data.lro_type) {
1239 #ifdef INET6
1240         case LRO_TYPE_IPV6_TCP:
1241                 inp = in6_pcblookup(&V_tcbinfo,
1242                     &pa->data.s_addr.v6,
1243                     pa->data.s_port,
1244                     &pa->data.d_addr.v6,
1245                     pa->data.d_port,
1246                     INPLOOKUP_WLOCKPCB,
1247                     ifp);
1248                 break;
1249 #endif
1250 #ifdef INET
1251         case LRO_TYPE_IPV4_TCP:
1252                 inp = in_pcblookup(&V_tcbinfo,
1253                     pa->data.s_addr.v4,
1254                     pa->data.s_port,
1255                     pa->data.d_addr.v4,
1256                     pa->data.d_port,
1257                     INPLOOKUP_WLOCKPCB,
1258                     ifp);
1259                 break;
1260 #endif
1261         default:
1262                 inp = NULL;
1263                 break;
1264         }
1265         return (inp);
1266 }
1267
1268 static inline bool
1269 tcp_lro_ack_valid(struct mbuf *m, struct tcphdr *th, uint32_t **ppts, bool *other_opts)
1270 {
1271         /*
1272          * This function returns two bits of valuable information.
1273          * a) Is what is present capable of being ack-compressed,
1274          *    we can ack-compress if there is no options or just
1275          *    a timestamp option, and of course the th_flags must
1276          *    be correct as well.
1277          * b) Our other options present such as SACK. This is
1278          *    used to determine if we want to wakeup or not.
1279          */
1280         bool ret = true;
1281
1282         switch (th->th_off << 2) {
1283         case (sizeof(*th) + TCPOLEN_TSTAMP_APPA):
1284                 *ppts = (uint32_t *)(th + 1);
1285                 /* Check if we have only one timestamp option. */
1286                 if (**ppts == TCP_LRO_TS_OPTION)
1287                         *other_opts = false;
1288                 else {
1289                         *other_opts = true;
1290                         ret = false;
1291                 }
1292                 break;
1293         case (sizeof(*th)):
1294                 /* No options. */
1295                 *ppts = NULL;
1296                 *other_opts = false;
1297                 break;
1298         default:
1299                 *ppts = NULL;
1300                 *other_opts = true;
1301                 ret = false;
1302                 break;
1303         }
1304         /* For ACKCMP we only accept ACK, PUSH, ECE and CWR. */
1305         if ((tcp_get_flags(th) & ~(TH_ACK | TH_PUSH | TH_ECE | TH_CWR)) != 0)
1306                 ret = false;
1307         /* If it has data on it we cannot compress it */
1308         if (m->m_pkthdr.lro_tcp_d_len)
1309                 ret = false;
1310
1311         /* ACK flag must be set. */
1312         if (!(tcp_get_flags(th) & TH_ACK))
1313                 ret = false;
1314         return (ret);
1315 }
1316
1317 static int
1318 tcp_lro_flush_tcphpts(struct lro_ctrl *lc, struct lro_entry *le)
1319 {
1320         struct inpcb *inp;
1321         struct tcpcb *tp;
1322         struct mbuf **pp, *cmp, *mv_to;
1323         struct ifnet *lagg_ifp;
1324         bool bpf_req, lagg_bpf_req, should_wake, can_append_old_cmp;
1325
1326         /* Check if packet doesn't belongs to our network interface. */
1327         if ((tcplro_stacks_wanting_mbufq == 0) ||
1328             (le->outer.data.vlan_id != 0) ||
1329             (le->inner.data.lro_type != LRO_TYPE_NONE))
1330                 return (TCP_LRO_CANNOT);
1331
1332 #ifdef INET6
1333         /*
1334          * Be proactive about unspecified IPv6 address in source. As
1335          * we use all-zero to indicate unbounded/unconnected pcb,
1336          * unspecified IPv6 address can be used to confuse us.
1337          *
1338          * Note that packets with unspecified IPv6 destination is
1339          * already dropped in ip6_input.
1340          */
1341         if (__predict_false(le->outer.data.lro_type == LRO_TYPE_IPV6_TCP &&
1342             IN6_IS_ADDR_UNSPECIFIED(&le->outer.data.s_addr.v6)))
1343                 return (TCP_LRO_CANNOT);
1344
1345         if (__predict_false(le->inner.data.lro_type == LRO_TYPE_IPV6_TCP &&
1346             IN6_IS_ADDR_UNSPECIFIED(&le->inner.data.s_addr.v6)))
1347                 return (TCP_LRO_CANNOT);
1348 #endif
1349         /* Lookup inp, if any. */
1350         inp = tcp_lro_lookup(lc->ifp,
1351             (le->inner.data.lro_type == LRO_TYPE_NONE) ? &le->outer : &le->inner);
1352         if (inp == NULL)
1353                 return (TCP_LRO_CANNOT);
1354
1355         counter_u64_add(tcp_inp_lro_locks_taken, 1);
1356
1357         /* Get TCP control structure. */
1358         tp = intotcpcb(inp);
1359
1360         /* Check if the inp is dead, Jim. */
1361         if (tp->t_state == TCPS_TIME_WAIT) {
1362                 INP_WUNLOCK(inp);
1363                 return (TCP_LRO_CANNOT);
1364         }
1365         if ((inp->inp_irq_cpu_set == 0)  && (lc->lro_cpu_is_set == 1)) {
1366                 inp->inp_irq_cpu = lc->lro_last_cpu;
1367                 inp->inp_irq_cpu_set = 1;
1368         }
1369         /* Check if the transport doesn't support the needed optimizations. */
1370         if ((inp->inp_flags2 & (INP_SUPPORTS_MBUFQ | INP_MBUF_ACKCMP)) == 0) {
1371                 INP_WUNLOCK(inp);
1372                 return (TCP_LRO_CANNOT);
1373         }
1374
1375         if (inp->inp_flags2 & INP_MBUF_QUEUE_READY)
1376                 should_wake = false;
1377         else
1378                 should_wake = true;
1379         /* Check if packets should be tapped to BPF. */
1380         bpf_req = bpf_peers_present(lc->ifp->if_bpf);
1381         lagg_bpf_req = false;
1382         lagg_ifp = NULL;
1383         if (lc->ifp->if_type == IFT_IEEE8023ADLAG ||
1384             lc->ifp->if_type == IFT_INFINIBANDLAG) {
1385                 struct lagg_port *lp = lc->ifp->if_lagg;
1386                 struct lagg_softc *sc = lp->lp_softc;
1387
1388                 lagg_ifp = sc->sc_ifp;
1389                 if (lagg_ifp != NULL)
1390                         lagg_bpf_req = bpf_peers_present(lagg_ifp->if_bpf);
1391         }
1392
1393         /* Strip and compress all the incoming packets. */
1394         can_append_old_cmp = true;
1395         cmp = NULL;
1396         for (pp = &le->m_head; *pp != NULL; ) {
1397                 mv_to = NULL;
1398                 if (do_bpf_strip_and_compress(inp, lc, le, pp,
1399                         &cmp, &mv_to, &should_wake, bpf_req,
1400                         lagg_bpf_req, lagg_ifp, can_append_old_cmp) == false) {
1401                         /* Advance to next mbuf. */
1402                         pp = &(*pp)->m_nextpkt;
1403                         /*
1404                          * Once we have appended we can't look in the pending
1405                          * inbound packets for a compressed ack to append to.
1406                          */
1407                         can_append_old_cmp = false;
1408                         /*
1409                          * Once we append we also need to stop adding to any
1410                          * compressed ack we were remembering. A new cmp
1411                          * ack will be required.
1412                          */
1413                         cmp = NULL;
1414                         tcp_lro_log(tp, lc, le, NULL, 25, 0, 0, 0, 0);
1415                 } else if (mv_to != NULL) {
1416                         /* We are asked to move pp up */
1417                         pp = &mv_to->m_nextpkt;
1418                         tcp_lro_log(tp, lc, le, NULL, 24, 0, 0, 0, 0);
1419                 } else
1420                         tcp_lro_log(tp, lc, le, NULL, 26, 0, 0, 0, 0);
1421         }
1422         /* Update "m_last_mbuf", if any. */
1423         if (pp == &le->m_head)
1424                 le->m_last_mbuf = *pp;
1425         else
1426                 le->m_last_mbuf = __containerof(pp, struct mbuf, m_nextpkt);
1427
1428         /* Check if any data mbufs left. */
1429         if (le->m_head != NULL) {
1430                 counter_u64_add(tcp_inp_lro_direct_queue, 1);
1431                 tcp_lro_log(tp, lc, le, NULL, 22, 1, inp->inp_flags2, 0, 1);
1432                 tcp_queue_pkts(inp, tp, le);
1433         }
1434         if (should_wake) {
1435                 /* Wakeup */
1436                 counter_u64_add(tcp_inp_lro_wokeup_queue, 1);
1437                 if ((*tp->t_fb->tfb_do_queued_segments)(inp->inp_socket, tp, 0))
1438                         inp = NULL;
1439         }
1440         if (inp != NULL)
1441                 INP_WUNLOCK(inp);
1442         return (0);     /* Success. */
1443 }
1444 #endif
1445
1446 void
1447 tcp_lro_flush(struct lro_ctrl *lc, struct lro_entry *le)
1448 {
1449         /* Only optimise if there are multiple packets waiting. */
1450 #ifdef TCPHPTS
1451         int error;
1452 #endif
1453
1454         NET_EPOCH_ASSERT();
1455 #ifdef TCPHPTS
1456         CURVNET_SET(lc->ifp->if_vnet);
1457         error = tcp_lro_flush_tcphpts(lc, le);
1458         CURVNET_RESTORE();
1459         if (error != 0) {
1460 #endif
1461                 tcp_lro_condense(lc, le);
1462                 tcp_flush_out_entry(lc, le);
1463 #ifdef TCPHPTS
1464         }
1465 #endif
1466         lc->lro_flushed++;
1467         bzero(le, sizeof(*le));
1468         LIST_INSERT_HEAD(&lc->lro_free, le, next);
1469 }
1470
1471 #ifdef HAVE_INLINE_FLSLL
1472 #define tcp_lro_msb_64(x) (1ULL << (flsll(x) - 1))
1473 #else
1474 static inline uint64_t
1475 tcp_lro_msb_64(uint64_t x)
1476 {
1477         x |= (x >> 1);
1478         x |= (x >> 2);
1479         x |= (x >> 4);
1480         x |= (x >> 8);
1481         x |= (x >> 16);
1482         x |= (x >> 32);
1483         return (x & ~(x >> 1));
1484 }
1485 #endif
1486
1487 /*
1488  * The tcp_lro_sort() routine is comparable to qsort(), except it has
1489  * a worst case complexity limit of O(MIN(N,64)*N), where N is the
1490  * number of elements to sort and 64 is the number of sequence bits
1491  * available. The algorithm is bit-slicing the 64-bit sequence number,
1492  * sorting one bit at a time from the most significant bit until the
1493  * least significant one, skipping the constant bits. This is
1494  * typically called a radix sort.
1495  */
1496 static void
1497 tcp_lro_sort(struct lro_mbuf_sort *parray, uint32_t size)
1498 {
1499         struct lro_mbuf_sort temp;
1500         uint64_t ones;
1501         uint64_t zeros;
1502         uint32_t x;
1503         uint32_t y;
1504
1505 repeat:
1506         /* for small arrays insertion sort is faster */
1507         if (size <= 12) {
1508                 for (x = 1; x < size; x++) {
1509                         temp = parray[x];
1510                         for (y = x; y > 0 && temp.seq < parray[y - 1].seq; y--)
1511                                 parray[y] = parray[y - 1];
1512                         parray[y] = temp;
1513                 }
1514                 return;
1515         }
1516
1517         /* compute sequence bits which are constant */
1518         ones = 0;
1519         zeros = 0;
1520         for (x = 0; x != size; x++) {
1521                 ones |= parray[x].seq;
1522                 zeros |= ~parray[x].seq;
1523         }
1524
1525         /* compute bits which are not constant into "ones" */
1526         ones &= zeros;
1527         if (ones == 0)
1528                 return;
1529
1530         /* pick the most significant bit which is not constant */
1531         ones = tcp_lro_msb_64(ones);
1532
1533         /*
1534          * Move entries having cleared sequence bits to the beginning
1535          * of the array:
1536          */
1537         for (x = y = 0; y != size; y++) {
1538                 /* skip set bits */
1539                 if (parray[y].seq & ones)
1540                         continue;
1541                 /* swap entries */
1542                 temp = parray[x];
1543                 parray[x] = parray[y];
1544                 parray[y] = temp;
1545                 x++;
1546         }
1547
1548         KASSERT(x != 0 && x != size, ("Memory is corrupted\n"));
1549
1550         /* sort zeros */
1551         tcp_lro_sort(parray, x);
1552
1553         /* sort ones */
1554         parray += x;
1555         size -= x;
1556         goto repeat;
1557 }
1558
1559 void
1560 tcp_lro_flush_all(struct lro_ctrl *lc)
1561 {
1562         uint64_t seq;
1563         uint64_t nseq;
1564         unsigned x;
1565
1566         NET_EPOCH_ASSERT();
1567         /* check if no mbufs to flush */
1568         if (lc->lro_mbuf_count == 0)
1569                 goto done;
1570         if (lc->lro_cpu_is_set == 0) {
1571                 if (lc->lro_last_cpu == curcpu) {
1572                         lc->lro_cnt_of_same_cpu++;
1573                         /* Have we reached the threshold to declare a cpu? */
1574                         if (lc->lro_cnt_of_same_cpu > tcp_lro_cpu_set_thresh)
1575                                 lc->lro_cpu_is_set = 1;
1576                 } else {
1577                         lc->lro_last_cpu = curcpu;
1578                         lc->lro_cnt_of_same_cpu = 0;
1579                 }
1580         }
1581         CURVNET_SET(lc->ifp->if_vnet);
1582
1583         /* get current time */
1584         binuptime(&lc->lro_last_queue_time);
1585
1586         /* sort all mbufs according to stream */
1587         tcp_lro_sort(lc->lro_mbuf_data, lc->lro_mbuf_count);
1588
1589         /* input data into LRO engine, stream by stream */
1590         seq = 0;
1591         for (x = 0; x != lc->lro_mbuf_count; x++) {
1592                 struct mbuf *mb;
1593
1594                 /* get mbuf */
1595                 mb = lc->lro_mbuf_data[x].mb;
1596
1597                 /* get sequence number, masking away the packet index */
1598                 nseq = lc->lro_mbuf_data[x].seq & (-1ULL << 24);
1599
1600                 /* check for new stream */
1601                 if (seq != nseq) {
1602                         seq = nseq;
1603
1604                         /* flush active streams */
1605                         tcp_lro_rx_done(lc);
1606                 }
1607
1608                 /* add packet to LRO engine */
1609                 if (tcp_lro_rx_common(lc, mb, 0, false) != 0) {
1610                         /* Flush anything we have acummulated */
1611                         tcp_lro_flush_active(lc);
1612                         /* input packet to network layer */
1613                         (*lc->ifp->if_input)(lc->ifp, mb);
1614                         lc->lro_queued++;
1615                         lc->lro_flushed++;
1616                 }
1617         }
1618         CURVNET_RESTORE();
1619 done:
1620         /* flush active streams */
1621         tcp_lro_rx_done(lc);
1622
1623 #ifdef TCPHPTS
1624         tcp_run_hpts();
1625 #endif
1626         lc->lro_mbuf_count = 0;
1627 }
1628
1629 #ifdef TCPHPTS
1630 static void
1631 build_ack_entry(struct tcp_ackent *ae, struct tcphdr *th, struct mbuf *m,
1632     uint32_t *ts_ptr, uint16_t iptos)
1633 {
1634         /*
1635          * Given a TCP ACK, summarize it down into the small TCP ACK
1636          * entry.
1637          */
1638         ae->timestamp = m->m_pkthdr.rcv_tstmp;
1639         ae->flags = 0;
1640         if (m->m_flags & M_TSTMP_LRO)
1641                 ae->flags |= TSTMP_LRO;
1642         else if (m->m_flags & M_TSTMP)
1643                 ae->flags |= TSTMP_HDWR;
1644         ae->seq = ntohl(th->th_seq);
1645         ae->ack = ntohl(th->th_ack);
1646         ae->flags |= tcp_get_flags(th);
1647         if (ts_ptr != NULL) {
1648                 ae->ts_value = ntohl(ts_ptr[1]);
1649                 ae->ts_echo = ntohl(ts_ptr[2]);
1650                 ae->flags |= HAS_TSTMP;
1651         }
1652         ae->win = ntohs(th->th_win);
1653         ae->codepoint = iptos;
1654 }
1655
1656 /*
1657  * Do BPF tap for either ACK_CMP packets or MBUF QUEUE type packets
1658  * and strip all, but the IPv4/IPv6 header.
1659  */
1660 static bool
1661 do_bpf_strip_and_compress(struct inpcb *inp, struct lro_ctrl *lc,
1662     struct lro_entry *le, struct mbuf **pp, struct mbuf **cmp, struct mbuf **mv_to,
1663     bool *should_wake, bool bpf_req, bool lagg_bpf_req, struct ifnet *lagg_ifp, bool can_append_old_cmp)
1664 {
1665         union {
1666                 void *ptr;
1667                 struct ip *ip4;
1668                 struct ip6_hdr *ip6;
1669         } l3;
1670         struct mbuf *m;
1671         struct mbuf *nm;
1672         struct tcphdr *th;
1673         struct tcp_ackent *ack_ent;
1674         uint32_t *ts_ptr;
1675         int32_t n_mbuf;
1676         bool other_opts, can_compress;
1677         uint8_t lro_type;
1678         uint16_t iptos;
1679         int tcp_hdr_offset;
1680         int idx;
1681
1682         /* Get current mbuf. */
1683         m = *pp;
1684
1685         /* Let the BPF see the packet */
1686         if (__predict_false(bpf_req))
1687                 ETHER_BPF_MTAP(lc->ifp, m);
1688
1689         if (__predict_false(lagg_bpf_req))
1690                 ETHER_BPF_MTAP(lagg_ifp, m);
1691
1692         tcp_hdr_offset = m->m_pkthdr.lro_tcp_h_off;
1693         lro_type = le->inner.data.lro_type;
1694         switch (lro_type) {
1695         case LRO_TYPE_NONE:
1696                 lro_type = le->outer.data.lro_type;
1697                 switch (lro_type) {
1698                 case LRO_TYPE_IPV4_TCP:
1699                         tcp_hdr_offset -= sizeof(*le->outer.ip4);
1700                         m->m_pkthdr.lro_etype = ETHERTYPE_IP;
1701                         break;
1702                 case LRO_TYPE_IPV6_TCP:
1703                         tcp_hdr_offset -= sizeof(*le->outer.ip6);
1704                         m->m_pkthdr.lro_etype = ETHERTYPE_IPV6;
1705                         break;
1706                 default:
1707                         goto compressed;
1708                 }
1709                 break;
1710         case LRO_TYPE_IPV4_TCP:
1711                 tcp_hdr_offset -= sizeof(*le->outer.ip4);
1712                 m->m_pkthdr.lro_etype = ETHERTYPE_IP;
1713                 break;
1714         case LRO_TYPE_IPV6_TCP:
1715                 tcp_hdr_offset -= sizeof(*le->outer.ip6);
1716                 m->m_pkthdr.lro_etype = ETHERTYPE_IPV6;
1717                 break;
1718         default:
1719                 goto compressed;
1720         }
1721
1722         MPASS(tcp_hdr_offset >= 0);
1723
1724         m_adj(m, tcp_hdr_offset);
1725         m->m_flags |= M_LRO_EHDRSTRP;
1726         m->m_flags &= ~M_ACKCMP;
1727         m->m_pkthdr.lro_tcp_h_off -= tcp_hdr_offset;
1728
1729         th = tcp_lro_get_th(m);
1730
1731         th->th_sum = 0;         /* TCP checksum is valid. */
1732
1733         /* Check if ACK can be compressed */
1734         can_compress = tcp_lro_ack_valid(m, th, &ts_ptr, &other_opts);
1735
1736         /* Now lets look at the should wake states */
1737         if ((other_opts == true) &&
1738             ((inp->inp_flags2 & INP_DONT_SACK_QUEUE) == 0)) {
1739                 /*
1740                  * If there are other options (SACK?) and the
1741                  * tcp endpoint has not expressly told us it does
1742                  * not care about SACKS, then we should wake up.
1743                  */
1744                 *should_wake = true;
1745         }
1746         /* Is the ack compressable? */
1747         if (can_compress == false)
1748                 goto done;
1749         /* Does the TCP endpoint support ACK compression? */
1750         if ((inp->inp_flags2 & INP_MBUF_ACKCMP) == 0)
1751                 goto done;
1752
1753         /* Lets get the TOS/traffic class field */
1754         l3.ptr = mtod(m, void *);
1755         switch (lro_type) {
1756         case LRO_TYPE_IPV4_TCP:
1757                 iptos = l3.ip4->ip_tos;
1758                 break;
1759         case LRO_TYPE_IPV6_TCP:
1760                 iptos = IPV6_TRAFFIC_CLASS(l3.ip6);
1761                 break;
1762         default:
1763                 iptos = 0;      /* Keep compiler happy. */
1764                 break;
1765         }
1766         /* Now lets get space if we don't have some already */
1767         if (*cmp == NULL) {
1768 new_one:
1769                 nm = tcp_lro_get_last_if_ackcmp(lc, le, inp, &n_mbuf, can_append_old_cmp);
1770                 if (__predict_false(nm == NULL))
1771                         goto done;
1772                 *cmp = nm;
1773                 if (n_mbuf) {
1774                         /*
1775                          *  Link in the new cmp ack to our in-order place,
1776                          * first set our cmp ack's next to where we are.
1777                          */
1778                         nm->m_nextpkt = m;
1779                         (*pp) = nm;
1780                         /*
1781                          * Set it up so mv_to is advanced to our
1782                          * compressed ack. This way the caller can
1783                          * advance pp to the right place.
1784                          */
1785                         *mv_to = nm;
1786                         /*
1787                          * Advance it here locally as well.
1788                          */
1789                         pp = &nm->m_nextpkt;
1790                 }
1791         } else {
1792                 /* We have one already we are working on */
1793                 nm = *cmp;
1794                 if (M_TRAILINGSPACE(nm) < sizeof(struct tcp_ackent)) {
1795                         /* We ran out of space */
1796                         inp->inp_flags2 |= INP_MBUF_L_ACKS;
1797                         goto new_one;
1798                 }
1799         }
1800         MPASS(M_TRAILINGSPACE(nm) >= sizeof(struct tcp_ackent));
1801         counter_u64_add(tcp_inp_lro_compressed, 1);
1802         le->compressed++;
1803         /* We can add in to the one on the tail */
1804         ack_ent = mtod(nm, struct tcp_ackent *);
1805         idx = (nm->m_len / sizeof(struct tcp_ackent));
1806         build_ack_entry(&ack_ent[idx], th, m, ts_ptr, iptos);
1807
1808         /* Bump the size of both pkt-hdr and len */
1809         nm->m_len += sizeof(struct tcp_ackent);
1810         nm->m_pkthdr.len += sizeof(struct tcp_ackent);
1811 compressed:
1812         /* Advance to next mbuf before freeing. */
1813         *pp = m->m_nextpkt;
1814         m->m_nextpkt = NULL;
1815         m_freem(m);
1816         return (true);
1817 done:
1818         counter_u64_add(tcp_uncomp_total, 1);
1819         le->uncompressed++;
1820         return (false);
1821 }
1822 #endif
1823
1824 static struct lro_head *
1825 tcp_lro_rx_get_bucket(struct lro_ctrl *lc, struct mbuf *m, struct lro_parser *parser)
1826 {
1827         u_long hash;
1828
1829         if (M_HASHTYPE_ISHASH(m)) {
1830                 hash = m->m_pkthdr.flowid;
1831         } else {
1832                 for (unsigned i = hash = 0; i != LRO_RAW_ADDRESS_MAX; i++)
1833                         hash += parser->data.raw[i];
1834         }
1835         return (&lc->lro_hash[hash % lc->lro_hashsz]);
1836 }
1837
1838 static int
1839 tcp_lro_rx_common(struct lro_ctrl *lc, struct mbuf *m, uint32_t csum, bool use_hash)
1840 {
1841         struct lro_parser pi;   /* inner address data */
1842         struct lro_parser po;   /* outer address data */
1843         struct lro_parser *pa;  /* current parser for TCP stream */
1844         struct lro_entry *le;
1845         struct lro_head *bucket;
1846         struct tcphdr *th;
1847         int tcp_data_len;
1848         int tcp_opt_len;
1849         int error;
1850         uint16_t tcp_data_sum;
1851
1852 #ifdef INET
1853         /* Quickly decide if packet cannot be LRO'ed */
1854         if (__predict_false(V_ipforwarding != 0))
1855                 return (TCP_LRO_CANNOT);
1856 #endif
1857 #ifdef INET6
1858         /* Quickly decide if packet cannot be LRO'ed */
1859         if (__predict_false(V_ip6_forwarding != 0))
1860                 return (TCP_LRO_CANNOT);
1861 #endif
1862         if (((m->m_pkthdr.csum_flags & (CSUM_DATA_VALID | CSUM_PSEUDO_HDR)) !=
1863              ((CSUM_DATA_VALID | CSUM_PSEUDO_HDR))) ||
1864             (m->m_pkthdr.csum_data != 0xffff)) {
1865                 /*
1866                  * The checksum either did not have hardware offload
1867                  * or it was a bad checksum. We can't LRO such
1868                  * a packet.
1869                  */
1870                 counter_u64_add(tcp_bad_csums, 1);
1871                 return (TCP_LRO_CANNOT);
1872         }
1873         /* We expect a contiguous header [eh, ip, tcp]. */
1874         pa = tcp_lro_parser(m, &po, &pi, true);
1875         if (__predict_false(pa == NULL))
1876                 return (TCP_LRO_NOT_SUPPORTED);
1877
1878         /* We don't expect any padding. */
1879         error = tcp_lro_trim_mbuf_chain(m, pa);
1880         if (__predict_false(error != 0))
1881                 return (error);
1882
1883 #ifdef INET
1884         switch (pa->data.lro_type) {
1885         case LRO_TYPE_IPV4_TCP:
1886                 error = tcp_lro_rx_ipv4(lc, m, pa->ip4);
1887                 if (__predict_false(error != 0))
1888                         return (error);
1889                 break;
1890         default:
1891                 break;
1892         }
1893 #endif
1894         /* If no hardware or arrival stamp on the packet add timestamp */
1895         if ((m->m_flags & (M_TSTMP_LRO | M_TSTMP)) == 0) {
1896                 m->m_pkthdr.rcv_tstmp = bintime2ns(&lc->lro_last_queue_time);
1897                 m->m_flags |= M_TSTMP_LRO;
1898         }
1899
1900         /* Get pointer to TCP header. */
1901         th = pa->tcp;
1902
1903         /* Don't process SYN packets. */
1904         if (__predict_false(tcp_get_flags(th) & TH_SYN))
1905                 return (TCP_LRO_CANNOT);
1906
1907         /* Get total TCP header length and compute payload length. */
1908         tcp_opt_len = (th->th_off << 2);
1909         tcp_data_len = m->m_pkthdr.len - ((uint8_t *)th -
1910             (uint8_t *)m->m_data) - tcp_opt_len;
1911         tcp_opt_len -= sizeof(*th);
1912
1913         /* Don't process invalid TCP headers. */
1914         if (__predict_false(tcp_opt_len < 0 || tcp_data_len < 0))
1915                 return (TCP_LRO_CANNOT);
1916
1917         /* Compute TCP data only checksum. */
1918         if (tcp_data_len == 0)
1919                 tcp_data_sum = 0;       /* no data, no checksum */
1920         else if (__predict_false(csum != 0))
1921                 tcp_data_sum = tcp_lro_rx_csum_data(pa, ~csum);
1922         else
1923                 tcp_data_sum = tcp_lro_rx_csum_data(pa, ~th->th_sum);
1924
1925         /* Save TCP info in mbuf. */
1926         m->m_nextpkt = NULL;
1927         m->m_pkthdr.rcvif = lc->ifp;
1928         m->m_pkthdr.lro_tcp_d_csum = tcp_data_sum;
1929         m->m_pkthdr.lro_tcp_d_len = tcp_data_len;
1930         m->m_pkthdr.lro_tcp_h_off = ((uint8_t *)th - (uint8_t *)m->m_data);
1931         m->m_pkthdr.lro_nsegs = 1;
1932
1933         /* Get hash bucket. */
1934         if (!use_hash) {
1935                 bucket = &lc->lro_hash[0];
1936         } else {
1937                 bucket = tcp_lro_rx_get_bucket(lc, m, pa);
1938         }
1939
1940         /* Try to find a matching previous segment. */
1941         LIST_FOREACH(le, bucket, hash_next) {
1942                 /* Compare addresses and ports. */
1943                 if (lro_address_compare(&po.data, &le->outer.data) == false ||
1944                     lro_address_compare(&pi.data, &le->inner.data) == false)
1945                         continue;
1946
1947                 /* Check if no data and old ACK. */
1948                 if (tcp_data_len == 0 &&
1949                     SEQ_LT(ntohl(th->th_ack), ntohl(le->ack_seq))) {
1950                         m_freem(m);
1951                         return (0);
1952                 }
1953
1954                 /* Mark "m" in the last spot. */
1955                 le->m_last_mbuf->m_nextpkt = m;
1956                 /* Now set the tail to "m". */
1957                 le->m_last_mbuf = m;
1958                 return (0);
1959         }
1960
1961         /* Try to find an empty slot. */
1962         if (LIST_EMPTY(&lc->lro_free))
1963                 return (TCP_LRO_NO_ENTRIES);
1964
1965         /* Start a new segment chain. */
1966         le = LIST_FIRST(&lc->lro_free);
1967         LIST_REMOVE(le, next);
1968         tcp_lro_active_insert(lc, bucket, le);
1969
1970         /* Make sure the headers are set. */
1971         le->inner = pi;
1972         le->outer = po;
1973
1974         /* Store time this entry was allocated. */
1975         le->alloc_time = lc->lro_last_queue_time;
1976
1977         tcp_set_entry_to_mbuf(lc, le, m, th);
1978
1979         /* Now set the tail to "m". */
1980         le->m_last_mbuf = m;
1981
1982         return (0);
1983 }
1984
1985 int
1986 tcp_lro_rx(struct lro_ctrl *lc, struct mbuf *m, uint32_t csum)
1987 {
1988         int error;
1989
1990         if (((m->m_pkthdr.csum_flags & (CSUM_DATA_VALID | CSUM_PSEUDO_HDR)) !=
1991              ((CSUM_DATA_VALID | CSUM_PSEUDO_HDR))) ||
1992             (m->m_pkthdr.csum_data != 0xffff)) {
1993                 /*
1994                  * The checksum either did not have hardware offload
1995                  * or it was a bad checksum. We can't LRO such
1996                  * a packet.
1997                  */
1998                 counter_u64_add(tcp_bad_csums, 1);
1999                 return (TCP_LRO_CANNOT);
2000         }
2001         /* get current time */
2002         binuptime(&lc->lro_last_queue_time);
2003         CURVNET_SET(lc->ifp->if_vnet);
2004         error = tcp_lro_rx_common(lc, m, csum, true);
2005         if (__predict_false(error != 0)) {
2006                 /*
2007                  * Flush anything we have acummulated
2008                  * ahead of this packet that can't
2009                  * be LRO'd. This preserves order.
2010                  */
2011                 tcp_lro_flush_active(lc);
2012         }
2013         CURVNET_RESTORE();
2014
2015         return (error);
2016 }
2017
2018 void
2019 tcp_lro_queue_mbuf(struct lro_ctrl *lc, struct mbuf *mb)
2020 {
2021         NET_EPOCH_ASSERT();
2022         /* sanity checks */
2023         if (__predict_false(lc->ifp == NULL || lc->lro_mbuf_data == NULL ||
2024             lc->lro_mbuf_max == 0)) {
2025                 /* packet drop */
2026                 m_freem(mb);
2027                 return;
2028         }
2029
2030         /* check if packet is not LRO capable */
2031         if (__predict_false((lc->ifp->if_capenable & IFCAP_LRO) == 0)) {
2032                 /* input packet to network layer */
2033                 (*lc->ifp->if_input) (lc->ifp, mb);
2034                 return;
2035         }
2036
2037         /* If no hardware or arrival stamp on the packet add timestamp */
2038         if ((tcplro_stacks_wanting_mbufq > 0) &&
2039             (tcp_less_accurate_lro_ts == 0) &&
2040             ((mb->m_flags & M_TSTMP) == 0)) {
2041                 /* Add in an LRO time since no hardware */
2042                 binuptime(&lc->lro_last_queue_time);
2043                 mb->m_pkthdr.rcv_tstmp = bintime2ns(&lc->lro_last_queue_time);
2044                 mb->m_flags |= M_TSTMP_LRO;
2045         }
2046
2047         /* create sequence number */
2048         lc->lro_mbuf_data[lc->lro_mbuf_count].seq =
2049             (((uint64_t)M_HASHTYPE_GET(mb)) << 56) |
2050             (((uint64_t)mb->m_pkthdr.flowid) << 24) |
2051             ((uint64_t)lc->lro_mbuf_count);
2052
2053         /* enter mbuf */
2054         lc->lro_mbuf_data[lc->lro_mbuf_count].mb = mb;
2055
2056         /* flush if array is full */
2057         if (__predict_false(++lc->lro_mbuf_count == lc->lro_mbuf_max))
2058                 tcp_lro_flush_all(lc);
2059 }
2060
2061 /* end */