sys/netinet/tcp_lro.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause
   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_private.h>
  59 #include <net/if_types.h>
  60 #include <net/infiniband.h>
  61 #include <net/if_lagg.h>
  62
  63 #include <netinet/in_systm.h>
  64 #include <netinet/in.h>
  65 #include <netinet/ip6.h>
  66 #include <netinet/ip.h>
  67 #include <netinet/ip_var.h>
  68 #include <netinet/in_pcb.h>
  69 #include <netinet6/in6_pcb.h>
  70 #include <netinet/tcp.h>
  71 #include <netinet/tcp_seq.h>
  72 #include <netinet/tcp_lro.h>
  73 #include <netinet/tcp_var.h>
  74 #include <netinet/tcpip.h>
  75 #include <netinet/tcp_hpts.h>
  76 #include <netinet/tcp_log_buf.h>
  77 #include <netinet/tcp_fsm.h>
  78 #include <netinet/udp.h>
  79 #include <netinet6/ip6_var.h>
  80
  81 #include <machine/in_cksum.h>
  82
  83 static MALLOC_DEFINE(M_LRO, "LRO", "LRO control structures");
  84
  85 #define TCP_LRO_TS_OPTION \
  86     ntohl((TCPOPT_NOP << 24) | (TCPOPT_NOP << 16) | \
  87           (TCPOPT_TIMESTAMP << 8) | TCPOLEN_TIMESTAMP)
  88
  89 static void     tcp_lro_rx_done(struct lro_ctrl *lc);
  90 static int      tcp_lro_rx_common(struct lro_ctrl *lc, struct mbuf *m,
  91                     uint32_t csum, bool use_hash);
  92
  93 #ifdef TCPHPTS
  94 static bool     do_bpf_strip_and_compress(struct tcpcb *, struct lro_ctrl *,
  95                 struct lro_entry *, struct mbuf **, struct mbuf **, struct mbuf **,
  96                 bool *, bool, bool, struct ifnet *, bool);
  97
  98 #endif
  99
 100 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, lro,  CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
 101     "TCP LRO");
 102
 103 static long tcplro_stacks_wanting_mbufq;
 104 counter_u64_t tcp_inp_lro_direct_queue;
 105 counter_u64_t tcp_inp_lro_wokeup_queue;
 106 counter_u64_t tcp_inp_lro_compressed;
 107 counter_u64_t tcp_inp_lro_locks_taken;
 108 counter_u64_t tcp_extra_mbuf;
 109 counter_u64_t tcp_would_have_but;
 110 counter_u64_t tcp_comp_total;
 111 counter_u64_t tcp_uncomp_total;
 112 counter_u64_t tcp_bad_csums;
 113
 114 static unsigned tcp_lro_entries = TCP_LRO_ENTRIES;
 115 SYSCTL_UINT(_net_inet_tcp_lro, OID_AUTO, entries,
 116     CTLFLAG_RDTUN | CTLFLAG_MPSAFE, &tcp_lro_entries, 0,
 117     "default number of LRO entries");
 118
 119 static uint32_t tcp_lro_cpu_set_thresh = TCP_LRO_CPU_DECLARATION_THRESH;
 120 SYSCTL_UINT(_net_inet_tcp_lro, OID_AUTO, lro_cpu_threshold,
 121     CTLFLAG_RDTUN | CTLFLAG_MPSAFE, &tcp_lro_cpu_set_thresh, 0,
 122     "Number of interrupts in a row on the same CPU that will make us declare an 'affinity' cpu?");
 123
 124 static uint32_t tcp_less_accurate_lro_ts = 0;
 125 SYSCTL_UINT(_net_inet_tcp_lro, OID_AUTO, lro_less_accurate,
 126     CTLFLAG_MPSAFE, &tcp_less_accurate_lro_ts, 0,
 127     "Do we trade off efficency by doing less timestamp operations for time accuracy?");
 128
 129 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, fullqueue, CTLFLAG_RD,
 130     &tcp_inp_lro_direct_queue, "Number of lro's fully queued to transport");
 131 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, wokeup, CTLFLAG_RD,
 132     &tcp_inp_lro_wokeup_queue, "Number of lro's where we woke up transport via hpts");
 133 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, compressed, CTLFLAG_RD,
 134     &tcp_inp_lro_compressed, "Number of lro's compressed and sent to transport");
 135 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, lockcnt, CTLFLAG_RD,
 136     &tcp_inp_lro_locks_taken, "Number of lro's inp_wlocks taken");
 137 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, extra_mbuf, CTLFLAG_RD,
 138     &tcp_extra_mbuf, "Number of times we had an extra compressed ack dropped into the tp");
 139 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, would_have_but, CTLFLAG_RD,
 140     &tcp_would_have_but, "Number of times we would have had an extra compressed, but mget failed");
 141 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, with_m_ackcmp, CTLFLAG_RD,
 142     &tcp_comp_total, "Number of mbufs queued with M_ACKCMP flags set");
 143 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, without_m_ackcmp, CTLFLAG_RD,
 144     &tcp_uncomp_total, "Number of mbufs queued without M_ACKCMP");
 145 SYSCTL_COUNTER_U64(_net_inet_tcp_lro, OID_AUTO, lro_badcsum, CTLFLAG_RD,
 146     &tcp_bad_csums, "Number of packets that the common code saw with bad csums");
 147
 148 void
 149 tcp_lro_reg_mbufq(void)
 150 {
 151         atomic_fetchadd_long(&tcplro_stacks_wanting_mbufq, 1);
 152 }
 153
 154 void
 155 tcp_lro_dereg_mbufq(void)
 156 {
 157         atomic_fetchadd_long(&tcplro_stacks_wanting_mbufq, -1);
 158 }
 159
 160 static __inline void
 161 tcp_lro_active_insert(struct lro_ctrl *lc, struct lro_head *bucket,
 162     struct lro_entry *le)
 163 {
 164
 165         LIST_INSERT_HEAD(&lc->lro_active, le, next);
 166         LIST_INSERT_HEAD(bucket, le, hash_next);
 167 }
 168
 169 static __inline void
 170 tcp_lro_active_remove(struct lro_entry *le)
 171 {
 172
 173         LIST_REMOVE(le, next);          /* active list */
 174         LIST_REMOVE(le, hash_next);     /* hash bucket */
 175 }
 176
 177 int
 178 tcp_lro_init(struct lro_ctrl *lc)
 179 {
 180         return (tcp_lro_init_args(lc, NULL, tcp_lro_entries, 0));
 181 }
 182
 183 int
 184 tcp_lro_init_args(struct lro_ctrl *lc, struct ifnet *ifp,
 185     unsigned lro_entries, unsigned lro_mbufs)
 186 {
 187         struct lro_entry *le;
 188         size_t size;
 189         unsigned i, elements;
 190
 191         lc->lro_bad_csum = 0;
 192         lc->lro_queued = 0;
 193         lc->lro_flushed = 0;
 194         lc->lro_mbuf_count = 0;
 195         lc->lro_mbuf_max = lro_mbufs;
 196         lc->lro_cnt = lro_entries;
 197         lc->lro_ackcnt_lim = TCP_LRO_ACKCNT_MAX;
 198         lc->lro_length_lim = TCP_LRO_LENGTH_MAX;
 199         lc->ifp = ifp;
 200         LIST_INIT(&lc->lro_free);
 201         LIST_INIT(&lc->lro_active);
 202
 203         /* create hash table to accelerate entry lookup */
 204         if (lro_entries > lro_mbufs)
 205                 elements = lro_entries;
 206         else
 207                 elements = lro_mbufs;
 208         lc->lro_hash = phashinit_flags(elements, M_LRO, &lc->lro_hashsz,
 209             HASH_NOWAIT);
 210         if (lc->lro_hash == NULL) {
 211                 memset(lc, 0, sizeof(*lc));
 212                 return (ENOMEM);
 213         }
 214
 215         /* compute size to allocate */
 216         size = (lro_mbufs * sizeof(struct lro_mbuf_sort)) +
 217             (lro_entries * sizeof(*le));
 218         lc->lro_mbuf_data = (struct lro_mbuf_sort *)
 219             malloc(size, M_LRO, M_NOWAIT | M_ZERO);
 220
 221         /* check for out of memory */
 222         if (lc->lro_mbuf_data == NULL) {
 223                 free(lc->lro_hash, M_LRO);
 224                 memset(lc, 0, sizeof(*lc));
 225                 return (ENOMEM);
 226         }
 227         /* compute offset for LRO entries */
 228         le = (struct lro_entry *)
 229             (lc->lro_mbuf_data + lro_mbufs);
 230
 231         /* setup linked list */
 232         for (i = 0; i != lro_entries; i++)
 233                 LIST_INSERT_HEAD(&lc->lro_free, le + i, next);
 234
 235         return (0);
 236 }
 237
 238 struct vxlan_header {
 239         uint32_t        vxlh_flags;
 240         uint32_t        vxlh_vni;
 241 };
 242
 243 static inline void *
 244 tcp_lro_low_level_parser(void *ptr, struct lro_parser *parser, bool update_data, bool is_vxlan, int mlen)
 245 {
 246         const struct ether_vlan_header *eh;
 247         void *old;
 248         uint16_t eth_type;
 249
 250         if (update_data)
 251                 memset(parser, 0, sizeof(*parser));
 252
 253         old = ptr;
 254
 255         if (is_vxlan) {
 256                 const struct vxlan_header *vxh;
 257                 vxh = ptr;
 258                 ptr = (uint8_t *)ptr + sizeof(*vxh);
 259                 if (update_data) {
 260                         parser->data.vxlan_vni =
 261                             vxh->vxlh_vni & htonl(0xffffff00);
 262                 }
 263         }
 264
 265         eh = ptr;
 266         if (__predict_false(eh->evl_encap_proto == htons(ETHERTYPE_VLAN))) {
 267                 eth_type = eh->evl_proto;
 268                 if (update_data) {
 269                         /* strip priority and keep VLAN ID only */
 270                         parser->data.vlan_id = eh->evl_tag & htons(EVL_VLID_MASK);
 271                 }
 272                 /* advance to next header */
 273                 ptr = (uint8_t *)ptr + ETHER_HDR_LEN + ETHER_VLAN_ENCAP_LEN;
 274                 mlen -= (ETHER_HDR_LEN  + ETHER_VLAN_ENCAP_LEN);
 275         } else {
 276                 eth_type = eh->evl_encap_proto;
 277                 /* advance to next header */
 278                 mlen -= ETHER_HDR_LEN;
 279                 ptr = (uint8_t *)ptr + ETHER_HDR_LEN;
 280         }
 281         if (__predict_false(mlen <= 0))
 282                 return (NULL);
 283         switch (eth_type) {
 284 #ifdef INET
 285         case htons(ETHERTYPE_IP):
 286                 parser->ip4 = ptr;
 287                 if (__predict_false(mlen < sizeof(struct ip)))
 288                         return (NULL);
 289                 /* Ensure there are no IPv4 options. */
 290                 if ((parser->ip4->ip_hl << 2) != sizeof (*parser->ip4))
 291                         break;
 292                 /* .. and the packet is not fragmented. */
 293                 if (parser->ip4->ip_off & htons(IP_MF|IP_OFFMASK))
 294                         break;
 295                 /* .. and the packet has valid src/dst addrs */
 296                 if (__predict_false(parser->ip4->ip_src.s_addr == INADDR_ANY ||
 297                         parser->ip4->ip_dst.s_addr == INADDR_ANY))
 298                         break;
 299                 ptr = (uint8_t *)ptr + (parser->ip4->ip_hl << 2);
 300                 mlen -= sizeof(struct ip);
 301                 if (update_data) {
 302                         parser->data.s_addr.v4 = parser->ip4->ip_src;
 303                         parser->data.d_addr.v4 = parser->ip4->ip_dst;
 304                 }
 305                 switch (parser->ip4->ip_p) {
 306                 case IPPROTO_UDP:
 307                         if (__predict_false(mlen < sizeof(struct udphdr)))
 308                                 return (NULL);
 309                         parser->udp = ptr;
 310                         if (update_data) {
 311                                 parser->data.lro_type = LRO_TYPE_IPV4_UDP;
 312                                 parser->data.s_port = parser->udp->uh_sport;
 313                                 parser->data.d_port = parser->udp->uh_dport;
 314                         } else {
 315                                 MPASS(parser->data.lro_type == LRO_TYPE_IPV4_UDP);
 316                         }
 317                         ptr = ((uint8_t *)ptr + sizeof(*parser->udp));
 318                         parser->total_hdr_len = (uint8_t *)ptr - (uint8_t *)old;
 319                         return (ptr);
 320                 case IPPROTO_TCP:
 321                         parser->tcp = ptr;
 322                         if (__predict_false(mlen < sizeof(struct tcphdr)))
 323                                 return (NULL);
 324                         if (update_data) {
 325                                 parser->data.lro_type = LRO_TYPE_IPV4_TCP;
 326                                 parser->data.s_port = parser->tcp->th_sport;
 327                                 parser->data.d_port = parser->tcp->th_dport;
 328                         } else {
 329                                 MPASS(parser->data.lro_type == LRO_TYPE_IPV4_TCP);
 330                         }
 331                         if (__predict_false(mlen < (parser->tcp->th_off << 2)))
 332                                 return (NULL);
 333                         ptr = (uint8_t *)ptr + (parser->tcp->th_off << 2);
 334                         parser->total_hdr_len = (uint8_t *)ptr - (uint8_t *)old;
 335                         return (ptr);
 336                 default:
 337                         break;
 338                 }
 339                 break;
 340 #endif
 341 #ifdef INET6
 342         case htons(ETHERTYPE_IPV6):
 343                 parser->ip6 = ptr;
 344                 if (__predict_false(mlen < sizeof(struct ip6_hdr)))
 345                         return (NULL);
 346                 /* Ensure the packet has valid src/dst addrs */
 347                 if (__predict_false(IN6_IS_ADDR_UNSPECIFIED(&parser->ip6->ip6_src) ||
 348                         IN6_IS_ADDR_UNSPECIFIED(&parser->ip6->ip6_dst)))
 349                         return (NULL);
 350                 ptr = (uint8_t *)ptr + sizeof(*parser->ip6);
 351                 if (update_data) {
 352                         parser->data.s_addr.v6 = parser->ip6->ip6_src;
 353                         parser->data.d_addr.v6 = parser->ip6->ip6_dst;
 354                 }
 355                 mlen -= sizeof(struct ip6_hdr);
 356                 switch (parser->ip6->ip6_nxt) {
 357                 case IPPROTO_UDP:
 358                         if (__predict_false(mlen < sizeof(struct udphdr)))
 359                                 return (NULL);
 360                         parser->udp = ptr;
 361                         if (update_data) {
 362                                 parser->data.lro_type = LRO_TYPE_IPV6_UDP;
 363                                 parser->data.s_port = parser->udp->uh_sport;
 364                                 parser->data.d_port = parser->udp->uh_dport;
 365                         } else {
 366                                 MPASS(parser->data.lro_type == LRO_TYPE_IPV6_UDP);
 367                         }
 368                         ptr = (uint8_t *)ptr + sizeof(*parser->udp);
 369                         parser->total_hdr_len = (uint8_t *)ptr - (uint8_t *)old;
 370                         return (ptr);
 371                 case IPPROTO_TCP:
 372                         if (__predict_false(mlen < sizeof(struct tcphdr)))
 373                                 return (NULL);
 374                         parser->tcp = ptr;
 375                         if (update_data) {
 376                                 parser->data.lro_type = LRO_TYPE_IPV6_TCP;
 377                                 parser->data.s_port = parser->tcp->th_sport;
 378                                 parser->data.d_port = parser->tcp->th_dport;
 379                         } else {
 380                                 MPASS(parser->data.lro_type == LRO_TYPE_IPV6_TCP);
 381                         }
 382                         if (__predict_false(mlen < (parser->tcp->th_off << 2)))
 383                                 return (NULL);
 384                         ptr = (uint8_t *)ptr + (parser->tcp->th_off << 2);
 385                         parser->total_hdr_len = (uint8_t *)ptr - (uint8_t *)old;
 386                         return (ptr);
 387                 default:
 388                         break;
 389                 }
 390                 break;
 391 #endif
 392         default:
 393                 break;
 394         }
 395         /* Invalid packet - cannot parse */
 396         return (NULL);
 397 }
 398
 399 static const int vxlan_csum = CSUM_INNER_L3_CALC | CSUM_INNER_L3_VALID |
 400     CSUM_INNER_L4_CALC | CSUM_INNER_L4_VALID;
 401
 402 static inline struct lro_parser *
 403 tcp_lro_parser(struct mbuf *m, struct lro_parser *po, struct lro_parser *pi, bool update_data)
 404 {
 405         void *data_ptr;
 406
 407         /* Try to parse outer headers first. */
 408         data_ptr = tcp_lro_low_level_parser(m->m_data, po, update_data, false, m->m_len);
 409         if (data_ptr == NULL || po->total_hdr_len > m->m_len)
 410                 return (NULL);
 411
 412         if (update_data) {
 413                 /* Store VLAN ID, if any. */
 414                 if (__predict_false(m->m_flags & M_VLANTAG)) {
 415                         po->data.vlan_id =
 416                             htons(m->m_pkthdr.ether_vtag) & htons(EVL_VLID_MASK);
 417                 }
 418                 /* Store decrypted flag, if any. */
 419                 if (__predict_false((m->m_pkthdr.csum_flags &
 420                     CSUM_TLS_MASK) == CSUM_TLS_DECRYPTED))
 421                         po->data.lro_flags |= LRO_FLAG_DECRYPTED;
 422         }
 423
 424         switch (po->data.lro_type) {
 425         case LRO_TYPE_IPV4_UDP:
 426         case LRO_TYPE_IPV6_UDP:
 427                 /* Check for VXLAN headers. */
 428                 if ((m->m_pkthdr.csum_flags & vxlan_csum) != vxlan_csum)
 429                         break;
 430
 431                 /* Try to parse inner headers. */
 432                 data_ptr = tcp_lro_low_level_parser(data_ptr, pi, update_data, true,
 433                                                     (m->m_len - ((caddr_t)data_ptr - m->m_data)));
 434                 if (data_ptr == NULL || (pi->total_hdr_len + po->total_hdr_len) > m->m_len)
 435                         break;
 436
 437                 /* Verify supported header types. */
 438                 switch (pi->data.lro_type) {
 439                 case LRO_TYPE_IPV4_TCP:
 440                 case LRO_TYPE_IPV6_TCP:
 441                         return (pi);
 442                 default:
 443                         break;
 444                 }
 445                 break;
 446         case LRO_TYPE_IPV4_TCP:
 447         case LRO_TYPE_IPV6_TCP:
 448                 if (update_data)
 449                         memset(pi, 0, sizeof(*pi));
 450                 return (po);
 451         default:
 452                 break;
 453         }
 454         return (NULL);
 455 }
 456
 457 static inline int
 458 tcp_lro_trim_mbuf_chain(struct mbuf *m, const struct lro_parser *po)
 459 {
 460         int len;
 461
 462         switch (po->data.lro_type) {
 463 #ifdef INET
 464         case LRO_TYPE_IPV4_TCP:
 465                 len = ((uint8_t *)po->ip4 - (uint8_t *)m->m_data) +
 466                     ntohs(po->ip4->ip_len);
 467                 break;
 468 #endif
 469 #ifdef INET6
 470         case LRO_TYPE_IPV6_TCP:
 471                 len = ((uint8_t *)po->ip6 - (uint8_t *)m->m_data) +
 472                     ntohs(po->ip6->ip6_plen) + sizeof(*po->ip6);
 473                 break;
 474 #endif
 475         default:
 476                 return (TCP_LRO_CANNOT);
 477         }
 478
 479         /*
 480          * If the frame is padded beyond the end of the IP packet,
 481          * then trim the extra bytes off:
 482          */
 483         if (__predict_true(m->m_pkthdr.len == len)) {
 484                 return (0);
 485         } else if (m->m_pkthdr.len > len) {
 486                 m_adj(m, len - m->m_pkthdr.len);
 487                 return (0);
 488         }
 489         return (TCP_LRO_CANNOT);
 490 }
 491
 492 static struct tcphdr *
 493 tcp_lro_get_th(struct mbuf *m)
 494 {
 495         return ((struct tcphdr *)((uint8_t *)m->m_data + m->m_pkthdr.lro_tcp_h_off));
 496 }
 497
 498 static void
 499 lro_free_mbuf_chain(struct mbuf *m)
 500 {
 501         struct mbuf *save;
 502
 503         while (m) {
 504                 save = m->m_nextpkt;
 505                 m->m_nextpkt = NULL;
 506                 m_freem(m);
 507                 m = save;
 508         }
 509 }
 510
 511 void
 512 tcp_lro_free(struct lro_ctrl *lc)
 513 {
 514         struct lro_entry *le;
 515         unsigned x;
 516
 517         /* reset LRO free list */
 518         LIST_INIT(&lc->lro_free);
 519
 520         /* free active mbufs, if any */
 521         while ((le = LIST_FIRST(&lc->lro_active)) != NULL) {
 522                 tcp_lro_active_remove(le);
 523                 lro_free_mbuf_chain(le->m_head);
 524         }
 525
 526         /* free hash table */
 527         free(lc->lro_hash, M_LRO);
 528         lc->lro_hash = NULL;
 529         lc->lro_hashsz = 0;
 530
 531         /* free mbuf array, if any */
 532         for (x = 0; x != lc->lro_mbuf_count; x++)
 533                 m_freem(lc->lro_mbuf_data[x].mb);
 534         lc->lro_mbuf_count = 0;
 535
 536         /* free allocated memory, if any */
 537         free(lc->lro_mbuf_data, M_LRO);
 538         lc->lro_mbuf_data = NULL;
 539 }
 540
 541 static uint16_t
 542 tcp_lro_rx_csum_tcphdr(const struct tcphdr *th)
 543 {
 544         const uint16_t *ptr;
 545         uint32_t csum;
 546         uint16_t len;
 547
 548         csum = -th->th_sum;     /* exclude checksum field */
 549         len = th->th_off;
 550         ptr = (const uint16_t *)th;
 551         while (len--) {
 552                 csum += *ptr;
 553                 ptr++;
 554                 csum += *ptr;
 555                 ptr++;
 556         }
 557         while (csum > 0xffff)
 558                 csum = (csum >> 16) + (csum & 0xffff);
 559
 560         return (csum);
 561 }
 562
 563 static uint16_t
 564 tcp_lro_rx_csum_data(const struct lro_parser *pa, uint16_t tcp_csum)
 565 {
 566         uint32_t c;
 567         uint16_t cs;
 568
 569         c = tcp_csum;
 570
 571         switch (pa->data.lro_type) {
 572 #ifdef INET6
 573         case LRO_TYPE_IPV6_TCP:
 574                 /* Compute full pseudo IPv6 header checksum. */
 575                 cs = in6_cksum_pseudo(pa->ip6, ntohs(pa->ip6->ip6_plen), pa->ip6->ip6_nxt, 0);
 576                 break;
 577 #endif
 578 #ifdef INET
 579         case LRO_TYPE_IPV4_TCP:
 580                 /* Compute full pseudo IPv4 header checsum. */
 581                 cs = in_addword(ntohs(pa->ip4->ip_len) - sizeof(*pa->ip4), IPPROTO_TCP);
 582                 cs = in_pseudo(pa->ip4->ip_src.s_addr, pa->ip4->ip_dst.s_addr, htons(cs));
 583                 break;
 584 #endif
 585         default:
 586                 cs = 0;         /* Keep compiler happy. */
 587                 break;
 588         }
 589
 590         /* Complement checksum. */
 591         cs = ~cs;
 592         c += cs;
 593
 594         /* Remove TCP header checksum. */
 595         cs = ~tcp_lro_rx_csum_tcphdr(pa->tcp);
 596         c += cs;
 597
 598         /* Compute checksum remainder. */
 599         while (c > 0xffff)
 600                 c = (c >> 16) + (c & 0xffff);
 601
 602         return (c);
 603 }
 604
 605 static void
 606 tcp_lro_rx_done(struct lro_ctrl *lc)
 607 {
 608         struct lro_entry *le;
 609
 610         while ((le = LIST_FIRST(&lc->lro_active)) != NULL) {
 611                 tcp_lro_active_remove(le);
 612                 tcp_lro_flush(lc, le);
 613         }
 614 }
 615
 616 static void
 617 tcp_lro_flush_active(struct lro_ctrl *lc)
 618 {
 619         struct lro_entry *le;
 620
 621         /*
 622          * Walk through the list of le entries, and
 623          * any one that does have packets flush. This
 624          * is called because we have an inbound packet
 625          * (e.g. SYN) that has to have all others flushed
 626          * in front of it. Note we have to do the remove
 627          * because tcp_lro_flush() assumes that the entry
 628          * is being freed. This is ok it will just get
 629          * reallocated again like it was new.
 630          */
 631         LIST_FOREACH(le, &lc->lro_active, next) {
 632                 if (le->m_head != NULL) {
 633                         tcp_lro_active_remove(le);
 634                         tcp_lro_flush(lc, le);
 635                 }
 636         }
 637 }
 638
 639 void
 640 tcp_lro_flush_inactive(struct lro_ctrl *lc, const struct timeval *timeout)
 641 {
 642         struct lro_entry *le, *le_tmp;
 643         uint64_t now, tov;
 644         struct bintime bt;
 645
 646         NET_EPOCH_ASSERT();
 647         if (LIST_EMPTY(&lc->lro_active))
 648                 return;
 649
 650         /* get timeout time and current time in ns */
 651         binuptime(&bt);
 652         now = bintime2ns(&bt);
 653         tov = ((timeout->tv_sec * 1000000000) + (timeout->tv_usec * 1000));
 654         LIST_FOREACH_SAFE(le, &lc->lro_active, next, le_tmp) {
 655                 if (now >= (bintime2ns(&le->alloc_time) + tov)) {
 656                         tcp_lro_active_remove(le);
 657                         tcp_lro_flush(lc, le);
 658                 }
 659         }
 660 }
 661
 662 #ifdef INET
 663 static int
 664 tcp_lro_rx_ipv4(struct lro_ctrl *lc, struct mbuf *m, struct ip *ip4)
 665 {
 666         uint16_t csum;
 667
 668         /* Legacy IP has a header checksum that needs to be correct. */
 669         if (m->m_pkthdr.csum_flags & CSUM_IP_CHECKED) {
 670                 if (__predict_false((m->m_pkthdr.csum_flags & CSUM_IP_VALID) == 0)) {
 671                         lc->lro_bad_csum++;
 672                         return (TCP_LRO_CANNOT);
 673                 }
 674         } else {
 675                 csum = in_cksum_hdr(ip4);
 676                 if (__predict_false(csum != 0)) {
 677                         lc->lro_bad_csum++;
 678                         return (TCP_LRO_CANNOT);
 679                 }
 680         }
 681         return (0);
 682 }
 683 #endif
 684
 685 #ifdef TCPHPTS
 686 static void
 687 tcp_lro_log(struct tcpcb *tp, const struct lro_ctrl *lc,
 688     const struct lro_entry *le, const struct mbuf *m,
 689     int frm, int32_t tcp_data_len, uint32_t th_seq,
 690     uint32_t th_ack, uint16_t th_win)
 691 {
 692         if (tcp_bblogging_on(tp)) {
 693                 union tcp_log_stackspecific log;
 694                 struct timeval tv, btv;
 695                 uint32_t cts;
 696
 697                 cts = tcp_get_usecs(&tv);
 698                 memset(&log, 0, sizeof(union tcp_log_stackspecific));
 699                 log.u_bbr.flex8 = frm;
 700                 log.u_bbr.flex1 = tcp_data_len;
 701                 if (m)
 702                         log.u_bbr.flex2 = m->m_pkthdr.len;
 703                 else
 704                         log.u_bbr.flex2 = 0;
 705                 if (le->m_head) {
 706                         log.u_bbr.flex3 = le->m_head->m_pkthdr.lro_nsegs;
 707                         log.u_bbr.flex4 = le->m_head->m_pkthdr.lro_tcp_d_len;
 708                         log.u_bbr.flex5 = le->m_head->m_pkthdr.len;
 709                         log.u_bbr.delRate = le->m_head->m_flags;
 710                         log.u_bbr.rttProp = le->m_head->m_pkthdr.rcv_tstmp;
 711                 }
 712                 log.u_bbr.inflight = th_seq;
 713                 log.u_bbr.delivered = th_ack;
 714                 log.u_bbr.timeStamp = cts;
 715                 log.u_bbr.epoch = le->next_seq;
 716                 log.u_bbr.lt_epoch = le->ack_seq;
 717                 log.u_bbr.pacing_gain = th_win;
 718                 log.u_bbr.cwnd_gain = le->window;
 719                 log.u_bbr.lost = curcpu;
 720                 log.u_bbr.cur_del_rate = (uintptr_t)m;
 721                 log.u_bbr.bw_inuse = (uintptr_t)le->m_head;
 722                 bintime2timeval(&lc->lro_last_queue_time, &btv);
 723                 log.u_bbr.flex6 = tcp_tv_to_usectick(&btv);
 724                 log.u_bbr.flex7 = le->compressed;
 725                 log.u_bbr.pacing_gain = le->uncompressed;
 726                 if (in_epoch(net_epoch_preempt))
 727                         log.u_bbr.inhpts = 1;
 728                 else
 729                         log.u_bbr.inhpts = 0;
 730                 TCP_LOG_EVENTP(tp, NULL, &tptosocket(tp)->so_rcv,
 731                     &tptosocket(tp)->so_snd,
 732                     TCP_LOG_LRO, 0, 0, &log, false, &tv);
 733         }
 734 }
 735 #endif
 736
 737 static inline void
 738 tcp_lro_assign_and_checksum_16(uint16_t *ptr, uint16_t value, uint16_t *psum)
 739 {
 740         uint32_t csum;
 741
 742         csum = 0xffff - *ptr + value;
 743         while (csum > 0xffff)
 744                 csum = (csum >> 16) + (csum & 0xffff);
 745         *ptr = value;
 746         *psum = csum;
 747 }
 748
 749 static uint16_t
 750 tcp_lro_update_checksum(const struct lro_parser *pa, const struct lro_entry *le,
 751     uint16_t payload_len, uint16_t delta_sum)
 752 {
 753         uint32_t csum;
 754         uint16_t tlen;
 755         uint16_t temp[5] = {};
 756
 757         switch (pa->data.lro_type) {
 758         case LRO_TYPE_IPV4_TCP:
 759                 /* Compute new IPv4 length. */
 760                 tlen = (pa->ip4->ip_hl << 2) + (pa->tcp->th_off << 2) + payload_len;
 761                 tcp_lro_assign_and_checksum_16(&pa->ip4->ip_len, htons(tlen), &temp[0]);
 762
 763                 /* Subtract delta from current IPv4 checksum. */
 764                 csum = pa->ip4->ip_sum + 0xffff - temp[0];
 765                 while (csum > 0xffff)
 766                         csum = (csum >> 16) + (csum & 0xffff);
 767                 tcp_lro_assign_and_checksum_16(&pa->ip4->ip_sum, csum, &temp[1]);
 768                 goto update_tcp_header;
 769
 770         case LRO_TYPE_IPV6_TCP:
 771                 /* Compute new IPv6 length. */
 772                 tlen = (pa->tcp->th_off << 2) + payload_len;
 773                 tcp_lro_assign_and_checksum_16(&pa->ip6->ip6_plen, htons(tlen), &temp[0]);
 774                 goto update_tcp_header;
 775
 776         case LRO_TYPE_IPV4_UDP:
 777                 /* Compute new IPv4 length. */
 778                 tlen = (pa->ip4->ip_hl << 2) + sizeof(*pa->udp) + payload_len;
 779                 tcp_lro_assign_and_checksum_16(&pa->ip4->ip_len, htons(tlen), &temp[0]);
 780
 781                 /* Subtract delta from current IPv4 checksum. */
 782                 csum = pa->ip4->ip_sum + 0xffff - temp[0];
 783                 while (csum > 0xffff)
 784                         csum = (csum >> 16) + (csum & 0xffff);
 785                 tcp_lro_assign_and_checksum_16(&pa->ip4->ip_sum, csum, &temp[1]);
 786                 goto update_udp_header;
 787
 788         case LRO_TYPE_IPV6_UDP:
 789                 /* Compute new IPv6 length. */
 790                 tlen = sizeof(*pa->udp) + payload_len;
 791                 tcp_lro_assign_and_checksum_16(&pa->ip6->ip6_plen, htons(tlen), &temp[0]);
 792                 goto update_udp_header;
 793
 794         default:
 795                 return (0);
 796         }
 797
 798 update_tcp_header:
 799         /* Compute current TCP header checksum. */
 800         temp[2] = tcp_lro_rx_csum_tcphdr(pa->tcp);
 801
 802         /* Incorporate the latest ACK into the TCP header. */
 803         pa->tcp->th_ack = le->ack_seq;
 804         pa->tcp->th_win = le->window;
 805
 806         /* Incorporate latest timestamp into the TCP header. */
 807         if (le->timestamp != 0) {
 808                 uint32_t *ts_ptr;
 809
 810                 ts_ptr = (uint32_t *)(pa->tcp + 1);
 811                 ts_ptr[1] = htonl(le->tsval);
 812                 ts_ptr[2] = le->tsecr;
 813         }
 814
 815         /* Compute new TCP header checksum. */
 816         temp[3] = tcp_lro_rx_csum_tcphdr(pa->tcp);
 817
 818         /* Compute new TCP checksum. */
 819         csum = pa->tcp->th_sum + 0xffff - delta_sum +
 820             0xffff - temp[0] + 0xffff - temp[3] + temp[2];
 821         while (csum > 0xffff)
 822                 csum = (csum >> 16) + (csum & 0xffff);
 823
 824         /* Assign new TCP checksum. */
 825         tcp_lro_assign_and_checksum_16(&pa->tcp->th_sum, csum, &temp[4]);
 826
 827         /* Compute all modififications affecting next checksum. */
 828         csum = temp[0] + temp[1] + 0xffff - temp[2] +
 829             temp[3] + temp[4] + delta_sum;
 830         while (csum > 0xffff)
 831                 csum = (csum >> 16) + (csum & 0xffff);
 832
 833         /* Return delta checksum to next stage, if any. */
 834         return (csum);
 835
 836 update_udp_header:
 837         tlen = sizeof(*pa->udp) + payload_len;
 838         /* Assign new UDP length and compute checksum delta. */
 839         tcp_lro_assign_and_checksum_16(&pa->udp->uh_ulen, htons(tlen), &temp[2]);
 840
 841         /* Check if there is a UDP checksum. */
 842         if (__predict_false(pa->udp->uh_sum != 0)) {
 843                 /* Compute new UDP checksum. */
 844                 csum = pa->udp->uh_sum + 0xffff - delta_sum +
 845                     0xffff - temp[0] + 0xffff - temp[2];
 846                 while (csum > 0xffff)
 847                         csum = (csum >> 16) + (csum & 0xffff);
 848                 /* Assign new UDP checksum. */
 849                 tcp_lro_assign_and_checksum_16(&pa->udp->uh_sum, csum, &temp[3]);
 850         }
 851
 852         /* Compute all modififications affecting next checksum. */
 853         csum = temp[0] + temp[1] + temp[2] + temp[3] + delta_sum;
 854         while (csum > 0xffff)
 855                 csum = (csum >> 16) + (csum & 0xffff);
 856
 857         /* Return delta checksum to next stage, if any. */
 858         return (csum);
 859 }
 860
 861 static void
 862 tcp_flush_out_entry(struct lro_ctrl *lc, struct lro_entry *le)
 863 {
 864         /* Check if we need to recompute any checksums. */
 865         if (le->needs_merge) {
 866                 uint16_t csum;
 867
 868                 switch (le->inner.data.lro_type) {
 869                 case LRO_TYPE_IPV4_TCP:
 870                         csum = tcp_lro_update_checksum(&le->inner, le,
 871                             le->m_head->m_pkthdr.lro_tcp_d_len,
 872                             le->m_head->m_pkthdr.lro_tcp_d_csum);
 873                         csum = tcp_lro_update_checksum(&le->outer, NULL,
 874                             le->m_head->m_pkthdr.lro_tcp_d_len +
 875                             le->inner.total_hdr_len, csum);
 876                         le->m_head->m_pkthdr.csum_flags = CSUM_DATA_VALID |
 877                             CSUM_PSEUDO_HDR | CSUM_IP_CHECKED | CSUM_IP_VALID;
 878                         le->m_head->m_pkthdr.csum_data = 0xffff;
 879                         if (__predict_false(le->outer.data.lro_flags & LRO_FLAG_DECRYPTED))
 880                                 le->m_head->m_pkthdr.csum_flags |= CSUM_TLS_DECRYPTED;
 881                         break;
 882                 case LRO_TYPE_IPV6_TCP:
 883                         csum = tcp_lro_update_checksum(&le->inner, le,
 884                             le->m_head->m_pkthdr.lro_tcp_d_len,
 885                             le->m_head->m_pkthdr.lro_tcp_d_csum);
 886                         csum = tcp_lro_update_checksum(&le->outer, NULL,
 887                             le->m_head->m_pkthdr.lro_tcp_d_len +
 888                             le->inner.total_hdr_len, csum);
 889                         le->m_head->m_pkthdr.csum_flags = CSUM_DATA_VALID |
 890                             CSUM_PSEUDO_HDR;
 891                         le->m_head->m_pkthdr.csum_data = 0xffff;
 892                         if (__predict_false(le->outer.data.lro_flags & LRO_FLAG_DECRYPTED))
 893                                 le->m_head->m_pkthdr.csum_flags |= CSUM_TLS_DECRYPTED;
 894                         break;
 895                 case LRO_TYPE_NONE:
 896                         switch (le->outer.data.lro_type) {
 897                         case LRO_TYPE_IPV4_TCP:
 898                                 csum = tcp_lro_update_checksum(&le->outer, le,
 899                                     le->m_head->m_pkthdr.lro_tcp_d_len,
 900                                     le->m_head->m_pkthdr.lro_tcp_d_csum);
 901                                 le->m_head->m_pkthdr.csum_flags = CSUM_DATA_VALID |
 902                                     CSUM_PSEUDO_HDR | CSUM_IP_CHECKED | CSUM_IP_VALID;
 903                                 le->m_head->m_pkthdr.csum_data = 0xffff;
 904                                 if (__predict_false(le->outer.data.lro_flags & LRO_FLAG_DECRYPTED))
 905                                         le->m_head->m_pkthdr.csum_flags |= CSUM_TLS_DECRYPTED;
 906                                 break;
 907                         case LRO_TYPE_IPV6_TCP:
 908                                 csum = tcp_lro_update_checksum(&le->outer, le,
 909                                     le->m_head->m_pkthdr.lro_tcp_d_len,
 910                                     le->m_head->m_pkthdr.lro_tcp_d_csum);
 911                                 le->m_head->m_pkthdr.csum_flags = CSUM_DATA_VALID |
 912                                     CSUM_PSEUDO_HDR;
 913                                 le->m_head->m_pkthdr.csum_data = 0xffff;
 914                                 if (__predict_false(le->outer.data.lro_flags & LRO_FLAG_DECRYPTED))
 915                                         le->m_head->m_pkthdr.csum_flags |= CSUM_TLS_DECRYPTED;
 916                                 break;
 917                         default:
 918                                 break;
 919                         }
 920                         break;
 921                 default:
 922                         break;
 923                 }
 924         }
 925
 926         /*
 927          * Break any chain, this is not set to NULL on the singleton
 928          * case m_nextpkt points to m_head. Other case set them
 929          * m_nextpkt to NULL in push_and_replace.
 930          */
 931         le->m_head->m_nextpkt = NULL;
 932         lc->lro_queued += le->m_head->m_pkthdr.lro_nsegs;
 933         (*lc->ifp->if_input)(lc->ifp, le->m_head);
 934 }
 935
 936 static void
 937 tcp_set_entry_to_mbuf(struct lro_ctrl *lc, struct lro_entry *le,
 938     struct mbuf *m, struct tcphdr *th)
 939 {
 940         uint32_t *ts_ptr;
 941         uint16_t tcp_data_len;
 942         uint16_t tcp_opt_len;
 943
 944         ts_ptr = (uint32_t *)(th + 1);
 945         tcp_opt_len = (th->th_off << 2);
 946         tcp_opt_len -= sizeof(*th);
 947
 948         /* Check if there is a timestamp option. */
 949         if (tcp_opt_len == 0 ||
 950             __predict_false(tcp_opt_len != TCPOLEN_TSTAMP_APPA ||
 951             *ts_ptr != TCP_LRO_TS_OPTION)) {
 952                 /* We failed to find the timestamp option. */
 953                 le->timestamp = 0;
 954         } else {
 955                 le->timestamp = 1;
 956                 le->tsval = ntohl(*(ts_ptr + 1));
 957                 le->tsecr = *(ts_ptr + 2);
 958         }
 959
 960         tcp_data_len = m->m_pkthdr.lro_tcp_d_len;
 961
 962         /* Pull out TCP sequence numbers and window size. */
 963         le->next_seq = ntohl(th->th_seq) + tcp_data_len;
 964         le->ack_seq = th->th_ack;
 965         le->window = th->th_win;
 966         le->flags = tcp_get_flags(th);
 967         le->needs_merge = 0;
 968
 969         /* Setup new data pointers. */
 970         le->m_head = m;
 971         le->m_tail = m_last(m);
 972 }
 973
 974 static void
 975 tcp_push_and_replace(struct lro_ctrl *lc, struct lro_entry *le, struct mbuf *m)
 976 {
 977         struct lro_parser *pa;
 978
 979         /*
 980          * Push up the stack of the current entry
 981          * and replace it with "m".
 982          */
 983         struct mbuf *msave;
 984
 985         /* Grab off the next and save it */
 986         msave = le->m_head->m_nextpkt;
 987         le->m_head->m_nextpkt = NULL;
 988
 989         /* Now push out the old entry */
 990         tcp_flush_out_entry(lc, le);
 991
 992         /* Re-parse new header, should not fail. */
 993         pa = tcp_lro_parser(m, &le->outer, &le->inner, false);
 994         KASSERT(pa != NULL,
 995             ("tcp_push_and_replace: LRO parser failed on m=%p\n", m));
 996
 997         /*
 998          * Now to replace the data properly in the entry
 999          * we have to reset the TCP header and
1000          * other fields.
1001          */
1002         tcp_set_entry_to_mbuf(lc, le, m, pa->tcp);
1003
1004         /* Restore the next list */
1005         m->m_nextpkt = msave;
1006 }
1007
1008 static void
1009 tcp_lro_mbuf_append_pkthdr(struct lro_entry *le, const struct mbuf *p)
1010 {
1011         struct mbuf *m;
1012         uint32_t csum;
1013
1014         m = le->m_head;
1015         if (m->m_pkthdr.lro_nsegs == 1) {
1016                 /* Compute relative checksum. */
1017                 csum = p->m_pkthdr.lro_tcp_d_csum;
1018         } else {
1019                 /* Merge TCP data checksums. */
1020                 csum = (uint32_t)m->m_pkthdr.lro_tcp_d_csum +
1021                     (uint32_t)p->m_pkthdr.lro_tcp_d_csum;
1022                 while (csum > 0xffff)
1023                         csum = (csum >> 16) + (csum & 0xffff);
1024         }
1025
1026         /* Update various counters. */
1027         m->m_pkthdr.len += p->m_pkthdr.lro_tcp_d_len;
1028         m->m_pkthdr.lro_tcp_d_csum = csum;
1029         m->m_pkthdr.lro_tcp_d_len += p->m_pkthdr.lro_tcp_d_len;
1030         m->m_pkthdr.lro_nsegs += p->m_pkthdr.lro_nsegs;
1031         le->needs_merge = 1;
1032 }
1033
1034 static void
1035 tcp_lro_condense(struct lro_ctrl *lc, struct lro_entry *le)
1036 {
1037         /*
1038          * Walk through the mbuf chain we
1039          * have on tap and compress/condense
1040          * as required.
1041          */
1042         uint32_t *ts_ptr;
1043         struct mbuf *m;
1044         struct tcphdr *th;
1045         uint32_t tcp_data_len_total;
1046         uint32_t tcp_data_seg_total;
1047         uint16_t tcp_data_len;
1048         uint16_t tcp_opt_len;
1049
1050         /*
1051          * First we must check the lead (m_head)
1052          * we must make sure that it is *not*
1053          * something that should be sent up
1054          * right away (sack etc).
1055          */
1056 again:
1057         m = le->m_head->m_nextpkt;
1058         if (m == NULL) {
1059                 /* Just one left. */
1060                 return;
1061         }
1062
1063         th = tcp_lro_get_th(m);
1064         tcp_opt_len = (th->th_off << 2);
1065         tcp_opt_len -= sizeof(*th);
1066         ts_ptr = (uint32_t *)(th + 1);
1067
1068         if (tcp_opt_len != 0 && __predict_false(tcp_opt_len != TCPOLEN_TSTAMP_APPA ||
1069             *ts_ptr != TCP_LRO_TS_OPTION)) {
1070                 /*
1071                  * Its not the timestamp. We can't
1072                  * use this guy as the head.
1073                  */
1074                 le->m_head->m_nextpkt = m->m_nextpkt;
1075                 tcp_push_and_replace(lc, le, m);
1076                 goto again;
1077         }
1078         if ((tcp_get_flags(th) & ~(TH_ACK | TH_PUSH)) != 0) {
1079                 /*
1080                  * Make sure that previously seen segments/ACKs are delivered
1081                  * before this segment, e.g. FIN.
1082                  */
1083                 le->m_head->m_nextpkt = m->m_nextpkt;
1084                 tcp_push_and_replace(lc, le, m);
1085                 goto again;
1086         }
1087         while((m = le->m_head->m_nextpkt) != NULL) {
1088                 /*
1089                  * condense m into le, first
1090                  * pull m out of the list.
1091                  */
1092                 le->m_head->m_nextpkt = m->m_nextpkt;
1093                 m->m_nextpkt = NULL;
1094                 /* Setup my data */
1095                 tcp_data_len = m->m_pkthdr.lro_tcp_d_len;
1096                 th = tcp_lro_get_th(m);
1097                 ts_ptr = (uint32_t *)(th + 1);
1098                 tcp_opt_len = (th->th_off << 2);
1099                 tcp_opt_len -= sizeof(*th);
1100                 tcp_data_len_total = le->m_head->m_pkthdr.lro_tcp_d_len + tcp_data_len;
1101                 tcp_data_seg_total = le->m_head->m_pkthdr.lro_nsegs + m->m_pkthdr.lro_nsegs;
1102
1103                 if (tcp_data_seg_total >= lc->lro_ackcnt_lim ||
1104                     tcp_data_len_total >= lc->lro_length_lim) {
1105                         /* Flush now if appending will result in overflow. */
1106                         tcp_push_and_replace(lc, le, m);
1107                         goto again;
1108                 }
1109                 if (tcp_opt_len != 0 &&
1110                     __predict_false(tcp_opt_len != TCPOLEN_TSTAMP_APPA ||
1111                     *ts_ptr != TCP_LRO_TS_OPTION)) {
1112                         /*
1113                          * Maybe a sack in the new one? We need to
1114                          * start all over after flushing the
1115                          * current le. We will go up to the beginning
1116                          * and flush it (calling the replace again possibly
1117                          * or just returning).
1118                          */
1119                         tcp_push_and_replace(lc, le, m);
1120                         goto again;
1121                 }
1122                 if ((tcp_get_flags(th) & ~(TH_ACK | TH_PUSH)) != 0) {
1123                         tcp_push_and_replace(lc, le, m);
1124                         goto again;
1125                 }
1126                 if (tcp_opt_len != 0) {
1127                         uint32_t tsval = ntohl(*(ts_ptr + 1));
1128                         /* Make sure timestamp values are increasing. */
1129                         if (TSTMP_GT(le->tsval, tsval))  {
1130                                 tcp_push_and_replace(lc, le, m);
1131                                 goto again;
1132                         }
1133                         le->tsval = tsval;
1134                         le->tsecr = *(ts_ptr + 2);
1135                 }
1136                 /* Try to append the new segment. */
1137                 if (__predict_false(ntohl(th->th_seq) != le->next_seq ||
1138                                     ((tcp_get_flags(th) & TH_ACK) !=
1139                                       (le->flags & TH_ACK)) ||
1140                                     (tcp_data_len == 0 &&
1141                                      le->ack_seq == th->th_ack &&
1142                                      le->window == th->th_win))) {
1143                         /* Out of order packet, non-ACK + ACK or dup ACK. */
1144                         tcp_push_and_replace(lc, le, m);
1145                         goto again;
1146                 }
1147                 if (tcp_data_len != 0 ||
1148                     SEQ_GT(ntohl(th->th_ack), ntohl(le->ack_seq))) {
1149                         le->next_seq += tcp_data_len;
1150                         le->ack_seq = th->th_ack;
1151                         le->window = th->th_win;
1152                         le->needs_merge = 1;
1153                 } else if (th->th_ack == le->ack_seq) {
1154                         if (WIN_GT(th->th_win, le->window)) {
1155                                 le->window = th->th_win;
1156                                 le->needs_merge = 1;
1157                         }
1158                 }
1159
1160                 if (tcp_data_len == 0) {
1161                         m_freem(m);
1162                         continue;
1163                 }
1164
1165                 /* Merge TCP data checksum and length to head mbuf. */
1166                 tcp_lro_mbuf_append_pkthdr(le, m);
1167
1168                 /*
1169                  * Adjust the mbuf so that m_data points to the first byte of
1170                  * the ULP payload.  Adjust the mbuf to avoid complications and
1171                  * append new segment to existing mbuf chain.
1172                  */
1173                 m_adj(m, m->m_pkthdr.len - tcp_data_len);
1174                 m_demote_pkthdr(m);
1175                 le->m_tail->m_next = m;
1176                 le->m_tail = m_last(m);
1177         }
1178 }
1179
1180 #ifdef TCPHPTS
1181 static void
1182 tcp_queue_pkts(struct tcpcb *tp, struct lro_entry *le)
1183 {
1184
1185         INP_WLOCK_ASSERT(tptoinpcb(tp));
1186
1187         STAILQ_HEAD(, mbuf) q = { le->m_head,
1188             &STAILQ_NEXT(le->m_last_mbuf, m_stailqpkt) };
1189         STAILQ_CONCAT(&tp->t_inqueue, &q);
1190         le->m_head = NULL;
1191         le->m_last_mbuf = NULL;
1192 }
1193
1194 static bool
1195 tcp_lro_check_wake_status(struct tcpcb *tp)
1196 {
1197
1198         if (tp->t_fb->tfb_early_wake_check != NULL)
1199                 return ((tp->t_fb->tfb_early_wake_check)(tp));
1200         return (false);
1201 }
1202
1203 static struct mbuf *
1204 tcp_lro_get_last_if_ackcmp(struct lro_ctrl *lc, struct lro_entry *le,
1205     struct tcpcb *tp, int32_t *new_m, bool can_append_old_cmp)
1206 {
1207         struct mbuf *m;
1208
1209         /* Look at the last mbuf if any in queue */
1210         if (can_append_old_cmp) {
1211                 m = STAILQ_LAST(&tp->t_inqueue, mbuf, m_stailqpkt);
1212                 if (m != NULL && (m->m_flags & M_ACKCMP) != 0) {
1213                         if (M_TRAILINGSPACE(m) >= sizeof(struct tcp_ackent)) {
1214                                 tcp_lro_log(tp, lc, le, NULL, 23, 0, 0, 0, 0);
1215                                 *new_m = 0;
1216                                 counter_u64_add(tcp_extra_mbuf, 1);
1217                                 return (m);
1218                         } else {
1219                                 /* Mark we ran out of space */
1220                                 tp->t_flags2 |= TF2_MBUF_L_ACKS;
1221                         }
1222                 }
1223         }
1224         /* Decide mbuf size. */
1225         tcp_lro_log(tp, lc, le, NULL, 21, 0, 0, 0, 0);
1226         if (tp->t_flags2 & TF2_MBUF_L_ACKS)
1227                 m = m_getcl(M_NOWAIT, MT_DATA, M_ACKCMP | M_PKTHDR);
1228         else
1229                 m = m_gethdr(M_NOWAIT, MT_DATA);
1230
1231         if (__predict_false(m == NULL)) {
1232                 counter_u64_add(tcp_would_have_but, 1);
1233                 return (NULL);
1234         }
1235         counter_u64_add(tcp_comp_total, 1);
1236         m->m_pkthdr.rcvif = lc->ifp;
1237         m->m_flags |= M_ACKCMP;
1238         *new_m = 1;
1239         return (m);
1240 }
1241
1242 static struct tcpcb *
1243 tcp_lro_lookup(struct ifnet *ifp, struct lro_parser *pa)
1244 {
1245         struct inpcb *inp;
1246
1247         switch (pa->data.lro_type) {
1248 #ifdef INET6
1249         case LRO_TYPE_IPV6_TCP:
1250                 inp = in6_pcblookup(&V_tcbinfo,
1251                     &pa->data.s_addr.v6,
1252                     pa->data.s_port,
1253                     &pa->data.d_addr.v6,
1254                     pa->data.d_port,
1255                     INPLOOKUP_WLOCKPCB,
1256                     ifp);
1257                 break;
1258 #endif
1259 #ifdef INET
1260         case LRO_TYPE_IPV4_TCP:
1261                 inp = in_pcblookup(&V_tcbinfo,
1262                     pa->data.s_addr.v4,
1263                     pa->data.s_port,
1264                     pa->data.d_addr.v4,
1265                     pa->data.d_port,
1266                     INPLOOKUP_WLOCKPCB,
1267                     ifp);
1268                 break;
1269 #endif
1270         default:
1271                 return (NULL);
1272         }
1273
1274         return (intotcpcb(inp));
1275 }
1276
1277 static inline bool
1278 tcp_lro_ack_valid(struct mbuf *m, struct tcphdr *th, uint32_t **ppts, bool *other_opts)
1279 {
1280         /*
1281          * This function returns two bits of valuable information.
1282          * a) Is what is present capable of being ack-compressed,
1283          *    we can ack-compress if there is no options or just
1284          *    a timestamp option, and of course the th_flags must
1285          *    be correct as well.
1286          * b) Our other options present such as SACK. This is
1287          *    used to determine if we want to wakeup or not.
1288          */
1289         bool ret = true;
1290
1291         switch (th->th_off << 2) {
1292         case (sizeof(*th) + TCPOLEN_TSTAMP_APPA):
1293                 *ppts = (uint32_t *)(th + 1);
1294                 /* Check if we have only one timestamp option. */
1295                 if (**ppts == TCP_LRO_TS_OPTION)
1296                         *other_opts = false;
1297                 else {
1298                         *other_opts = true;
1299                         ret = false;
1300                 }
1301                 break;
1302         case (sizeof(*th)):
1303                 /* No options. */
1304                 *ppts = NULL;
1305                 *other_opts = false;
1306                 break;
1307         default:
1308                 *ppts = NULL;
1309                 *other_opts = true;
1310                 ret = false;
1311                 break;
1312         }
1313         /* For ACKCMP we only accept ACK, PUSH, ECE and CWR. */
1314         if ((tcp_get_flags(th) & ~(TH_ACK | TH_PUSH | TH_ECE | TH_CWR)) != 0)
1315                 ret = false;
1316         /* If it has data on it we cannot compress it */
1317         if (m->m_pkthdr.lro_tcp_d_len)
1318                 ret = false;
1319
1320         /* ACK flag must be set. */
1321         if (!(tcp_get_flags(th) & TH_ACK))
1322                 ret = false;
1323         return (ret);
1324 }
1325
1326 static int
1327 tcp_lro_flush_tcphpts(struct lro_ctrl *lc, struct lro_entry *le)
1328 {
1329         struct tcpcb *tp;
1330         struct mbuf **pp, *cmp, *mv_to;
1331         struct ifnet *lagg_ifp;
1332         bool bpf_req, lagg_bpf_req, should_wake, can_append_old_cmp;
1333
1334         /* Check if packet doesn't belongs to our network interface. */
1335         if ((tcplro_stacks_wanting_mbufq == 0) ||
1336             (le->outer.data.vlan_id != 0) ||
1337             (le->inner.data.lro_type != LRO_TYPE_NONE))
1338                 return (TCP_LRO_CANNOT);
1339
1340 #ifdef INET6
1341         /*
1342          * Be proactive about unspecified IPv6 address in source. As
1343          * we use all-zero to indicate unbounded/unconnected pcb,
1344          * unspecified IPv6 address can be used to confuse us.
1345          *
1346          * Note that packets with unspecified IPv6 destination is
1347          * already dropped in ip6_input.
1348          */
1349         if (__predict_false(le->outer.data.lro_type == LRO_TYPE_IPV6_TCP &&
1350             IN6_IS_ADDR_UNSPECIFIED(&le->outer.data.s_addr.v6)))
1351                 return (TCP_LRO_CANNOT);
1352
1353         if (__predict_false(le->inner.data.lro_type == LRO_TYPE_IPV6_TCP &&
1354             IN6_IS_ADDR_UNSPECIFIED(&le->inner.data.s_addr.v6)))
1355                 return (TCP_LRO_CANNOT);
1356 #endif
1357         /* Lookup inp, if any.  Returns locked TCP inpcb. */
1358         tp = tcp_lro_lookup(lc->ifp,
1359             (le->inner.data.lro_type == LRO_TYPE_NONE) ? &le->outer : &le->inner);
1360         if (tp == NULL)
1361                 return (TCP_LRO_CANNOT);
1362
1363         counter_u64_add(tcp_inp_lro_locks_taken, 1);
1364
1365         /* Check if the inp is dead, Jim. */
1366         if (tp->t_state == TCPS_TIME_WAIT) {
1367                 INP_WUNLOCK(tptoinpcb(tp));
1368                 return (TCP_LRO_CANNOT);
1369         }
1370         if (tp->t_lro_cpu == HPTS_CPU_NONE && lc->lro_cpu_is_set == 1)
1371                 tp->t_lro_cpu = lc->lro_last_cpu;
1372         /* Check if the transport doesn't support the needed optimizations. */
1373         if ((tp->t_flags2 & (TF2_SUPPORTS_MBUFQ | TF2_MBUF_ACKCMP)) == 0) {
1374                 INP_WUNLOCK(tptoinpcb(tp));
1375                 return (TCP_LRO_CANNOT);
1376         }
1377
1378         if (tp->t_flags2 & TF2_MBUF_QUEUE_READY)
1379                 should_wake = false;
1380         else
1381                 should_wake = true;
1382         /* Check if packets should be tapped to BPF. */
1383         bpf_req = bpf_peers_present(lc->ifp->if_bpf);
1384         lagg_bpf_req = false;
1385         lagg_ifp = NULL;
1386         if (lc->ifp->if_type == IFT_IEEE8023ADLAG ||
1387             lc->ifp->if_type == IFT_INFINIBANDLAG) {
1388                 struct lagg_port *lp = lc->ifp->if_lagg;
1389                 struct lagg_softc *sc = lp->lp_softc;
1390
1391                 lagg_ifp = sc->sc_ifp;
1392                 if (lagg_ifp != NULL)
1393                         lagg_bpf_req = bpf_peers_present(lagg_ifp->if_bpf);
1394         }
1395
1396         /* Strip and compress all the incoming packets. */
1397         can_append_old_cmp = true;
1398         cmp = NULL;
1399         for (pp = &le->m_head; *pp != NULL; ) {
1400                 mv_to = NULL;
1401                 if (do_bpf_strip_and_compress(tp, lc, le, pp,
1402                         &cmp, &mv_to, &should_wake, bpf_req,
1403                         lagg_bpf_req, lagg_ifp, can_append_old_cmp) == false) {
1404                         /* Advance to next mbuf. */
1405                         pp = &(*pp)->m_nextpkt;
1406                         /*
1407                          * Once we have appended we can't look in the pending
1408                          * inbound packets for a compressed ack to append to.
1409                          */
1410                         can_append_old_cmp = false;
1411                         /*
1412                          * Once we append we also need to stop adding to any
1413                          * compressed ack we were remembering. A new cmp
1414                          * ack will be required.
1415                          */
1416                         cmp = NULL;
1417                         tcp_lro_log(tp, lc, le, NULL, 25, 0, 0, 0, 0);
1418                 } else if (mv_to != NULL) {
1419                         /* We are asked to move pp up */
1420                         pp = &mv_to->m_nextpkt;
1421                         tcp_lro_log(tp, lc, le, NULL, 24, 0, 0, 0, 0);
1422                 } else
1423                         tcp_lro_log(tp, lc, le, NULL, 26, 0, 0, 0, 0);
1424         }
1425         /* Update "m_last_mbuf", if any. */
1426         if (pp == &le->m_head)
1427                 le->m_last_mbuf = *pp;
1428         else
1429                 le->m_last_mbuf = __containerof(pp, struct mbuf, m_nextpkt);
1430
1431         /* Check if any data mbufs left. */
1432         if (le->m_head != NULL) {
1433                 counter_u64_add(tcp_inp_lro_direct_queue, 1);
1434                 tcp_lro_log(tp, lc, le, NULL, 22, 1, tp->t_flags2, 0, 1);
1435                 tcp_queue_pkts(tp, le);
1436         }
1437         if (should_wake) {
1438                 /* Wakeup */
1439                 counter_u64_add(tcp_inp_lro_wokeup_queue, 1);
1440                 if ((*tp->t_fb->tfb_do_queued_segments)(tp, 0))
1441                         /* TCP cb gone and unlocked. */
1442                         return (0);
1443         }
1444         INP_WUNLOCK(tptoinpcb(tp));
1445
1446         return (0);     /* Success. */
1447 }
1448 #endif
1449
1450 void
1451 tcp_lro_flush(struct lro_ctrl *lc, struct lro_entry *le)
1452 {
1453         /* Only optimise if there are multiple packets waiting. */
1454 #ifdef TCPHPTS
1455         int error;
1456 #endif
1457
1458         NET_EPOCH_ASSERT();
1459 #ifdef TCPHPTS
1460         CURVNET_SET(lc->ifp->if_vnet);
1461         error = tcp_lro_flush_tcphpts(lc, le);
1462         CURVNET_RESTORE();
1463         if (error != 0) {
1464 #endif
1465                 tcp_lro_condense(lc, le);
1466                 tcp_flush_out_entry(lc, le);
1467 #ifdef TCPHPTS
1468         }
1469 #endif
1470         lc->lro_flushed++;
1471         bzero(le, sizeof(*le));
1472         LIST_INSERT_HEAD(&lc->lro_free, le, next);
1473 }
1474
1475 #define tcp_lro_msb_64(x) (1ULL << (flsll(x) - 1))
1476
1477 /*
1478  * The tcp_lro_sort() routine is comparable to qsort(), except it has
1479  * a worst case complexity limit of O(MIN(N,64)*N), where N is the
1480  * number of elements to sort and 64 is the number of sequence bits
1481  * available. The algorithm is bit-slicing the 64-bit sequence number,
1482  * sorting one bit at a time from the most significant bit until the
1483  * least significant one, skipping the constant bits. This is
1484  * typically called a radix sort.
1485  */
1486 static void
1487 tcp_lro_sort(struct lro_mbuf_sort *parray, uint32_t size)
1488 {
1489         struct lro_mbuf_sort temp;
1490         uint64_t ones;
1491         uint64_t zeros;
1492         uint32_t x;
1493         uint32_t y;
1494
1495 repeat:
1496         /* for small arrays insertion sort is faster */
1497         if (size <= 12) {
1498                 for (x = 1; x < size; x++) {
1499                         temp = parray[x];
1500                         for (y = x; y > 0 && temp.seq < parray[y - 1].seq; y--)
1501                                 parray[y] = parray[y - 1];
1502                         parray[y] = temp;
1503                 }
1504                 return;
1505         }
1506
1507         /* compute sequence bits which are constant */
1508         ones = 0;
1509         zeros = 0;
1510         for (x = 0; x != size; x++) {
1511                 ones |= parray[x].seq;
1512                 zeros |= ~parray[x].seq;
1513         }
1514
1515         /* compute bits which are not constant into "ones" */
1516         ones &= zeros;
1517         if (ones == 0)
1518                 return;
1519
1520         /* pick the most significant bit which is not constant */
1521         ones = tcp_lro_msb_64(ones);
1522
1523         /*
1524          * Move entries having cleared sequence bits to the beginning
1525          * of the array:
1526          */
1527         for (x = y = 0; y != size; y++) {
1528                 /* skip set bits */
1529                 if (parray[y].seq & ones)
1530                         continue;
1531                 /* swap entries */
1532                 temp = parray[x];
1533                 parray[x] = parray[y];
1534                 parray[y] = temp;
1535                 x++;
1536         }
1537
1538         KASSERT(x != 0 && x != size, ("Memory is corrupted\n"));
1539
1540         /* sort zeros */
1541         tcp_lro_sort(parray, x);
1542
1543         /* sort ones */
1544         parray += x;
1545         size -= x;
1546         goto repeat;
1547 }
1548
1549 void
1550 tcp_lro_flush_all(struct lro_ctrl *lc)
1551 {
1552         uint64_t seq;
1553         uint64_t nseq;
1554         unsigned x;
1555
1556         NET_EPOCH_ASSERT();
1557         /* check if no mbufs to flush */
1558         if (lc->lro_mbuf_count == 0)
1559                 goto done;
1560         if (lc->lro_cpu_is_set == 0) {
1561                 if (lc->lro_last_cpu == curcpu) {
1562                         lc->lro_cnt_of_same_cpu++;
1563                         /* Have we reached the threshold to declare a cpu? */
1564                         if (lc->lro_cnt_of_same_cpu > tcp_lro_cpu_set_thresh)
1565                                 lc->lro_cpu_is_set = 1;
1566                 } else {
1567                         lc->lro_last_cpu = curcpu;
1568                         lc->lro_cnt_of_same_cpu = 0;
1569                 }
1570         }
1571         CURVNET_SET(lc->ifp->if_vnet);
1572
1573         /* get current time */
1574         binuptime(&lc->lro_last_queue_time);
1575
1576         /* sort all mbufs according to stream */
1577         tcp_lro_sort(lc->lro_mbuf_data, lc->lro_mbuf_count);
1578
1579         /* input data into LRO engine, stream by stream */
1580         seq = 0;
1581         for (x = 0; x != lc->lro_mbuf_count; x++) {
1582                 struct mbuf *mb;
1583
1584                 /* get mbuf */
1585                 mb = lc->lro_mbuf_data[x].mb;
1586
1587                 /* get sequence number, masking away the packet index */
1588                 nseq = lc->lro_mbuf_data[x].seq & (-1ULL << 24);
1589
1590                 /* check for new stream */
1591                 if (seq != nseq) {
1592                         seq = nseq;
1593
1594                         /* flush active streams */
1595                         tcp_lro_rx_done(lc);
1596                 }
1597
1598                 /* add packet to LRO engine */
1599                 if (tcp_lro_rx_common(lc, mb, 0, false) != 0) {
1600                         /* Flush anything we have acummulated */
1601                         tcp_lro_flush_active(lc);
1602                         /* input packet to network layer */
1603                         (*lc->ifp->if_input)(lc->ifp, mb);
1604                         lc->lro_queued++;
1605                         lc->lro_flushed++;
1606                 }
1607         }
1608         CURVNET_RESTORE();
1609 done:
1610         /* flush active streams */
1611         tcp_lro_rx_done(lc);
1612
1613 #ifdef TCPHPTS
1614         tcp_run_hpts();
1615 #endif
1616         lc->lro_mbuf_count = 0;
1617 }
1618
1619 #ifdef TCPHPTS
1620 static void
1621 build_ack_entry(struct tcp_ackent *ae, struct tcphdr *th, struct mbuf *m,
1622     uint32_t *ts_ptr, uint16_t iptos)
1623 {
1624         /*
1625          * Given a TCP ACK, summarize it down into the small TCP ACK
1626          * entry.
1627          */
1628         ae->timestamp = m->m_pkthdr.rcv_tstmp;
1629         ae->flags = 0;
1630         if (m->m_flags & M_TSTMP_LRO)
1631                 ae->flags |= TSTMP_LRO;
1632         else if (m->m_flags & M_TSTMP)
1633                 ae->flags |= TSTMP_HDWR;
1634         ae->seq = ntohl(th->th_seq);
1635         ae->ack = ntohl(th->th_ack);
1636         ae->flags |= tcp_get_flags(th);
1637         if (ts_ptr != NULL) {
1638                 ae->ts_value = ntohl(ts_ptr[1]);
1639                 ae->ts_echo = ntohl(ts_ptr[2]);
1640                 ae->flags |= HAS_TSTMP;
1641         }
1642         ae->win = ntohs(th->th_win);
1643         ae->codepoint = iptos;
1644 }
1645
1646 /*
1647  * Do BPF tap for either ACK_CMP packets or MBUF QUEUE type packets
1648  * and strip all, but the IPv4/IPv6 header.
1649  */
1650 static bool
1651 do_bpf_strip_and_compress(struct tcpcb *tp, struct lro_ctrl *lc,
1652     struct lro_entry *le, struct mbuf **pp, struct mbuf **cmp, struct mbuf **mv_to,
1653     bool *should_wake, bool bpf_req, bool lagg_bpf_req, struct ifnet *lagg_ifp, bool can_append_old_cmp)
1654 {
1655         union {
1656                 void *ptr;
1657                 struct ip *ip4;
1658                 struct ip6_hdr *ip6;
1659         } l3;
1660         struct mbuf *m;
1661         struct mbuf *nm;
1662         struct tcphdr *th;
1663         struct tcp_ackent *ack_ent;
1664         uint32_t *ts_ptr;
1665         int32_t n_mbuf;
1666         bool other_opts, can_compress;
1667         uint8_t lro_type;
1668         uint16_t iptos;
1669         int tcp_hdr_offset;
1670         int idx;
1671
1672         /* Get current mbuf. */
1673         m = *pp;
1674
1675         /* Let the BPF see the packet */
1676         if (__predict_false(bpf_req))
1677                 ETHER_BPF_MTAP(lc->ifp, m);
1678
1679         if (__predict_false(lagg_bpf_req))
1680                 ETHER_BPF_MTAP(lagg_ifp, m);
1681
1682         tcp_hdr_offset = m->m_pkthdr.lro_tcp_h_off;
1683         lro_type = le->inner.data.lro_type;
1684         switch (lro_type) {
1685         case LRO_TYPE_NONE:
1686                 lro_type = le->outer.data.lro_type;
1687                 switch (lro_type) {
1688                 case LRO_TYPE_IPV4_TCP:
1689                         tcp_hdr_offset -= sizeof(*le->outer.ip4);
1690                         m->m_pkthdr.lro_etype = ETHERTYPE_IP;
1691                         break;
1692                 case LRO_TYPE_IPV6_TCP:
1693                         tcp_hdr_offset -= sizeof(*le->outer.ip6);
1694                         m->m_pkthdr.lro_etype = ETHERTYPE_IPV6;
1695                         break;
1696                 default:
1697                         goto compressed;
1698                 }
1699                 break;
1700         case LRO_TYPE_IPV4_TCP:
1701                 tcp_hdr_offset -= sizeof(*le->outer.ip4);
1702                 m->m_pkthdr.lro_etype = ETHERTYPE_IP;
1703                 break;
1704         case LRO_TYPE_IPV6_TCP:
1705                 tcp_hdr_offset -= sizeof(*le->outer.ip6);
1706                 m->m_pkthdr.lro_etype = ETHERTYPE_IPV6;
1707                 break;
1708         default:
1709                 goto compressed;
1710         }
1711
1712         MPASS(tcp_hdr_offset >= 0);
1713
1714         m_adj(m, tcp_hdr_offset);
1715         m->m_flags |= M_LRO_EHDRSTRP;
1716         m->m_flags &= ~M_ACKCMP;
1717         m->m_pkthdr.lro_tcp_h_off -= tcp_hdr_offset;
1718
1719         th = tcp_lro_get_th(m);
1720
1721         th->th_sum = 0;         /* TCP checksum is valid. */
1722
1723         /* Check if ACK can be compressed */
1724         can_compress = tcp_lro_ack_valid(m, th, &ts_ptr, &other_opts);
1725
1726         /* Now lets look at the should wake states */
1727         if ((other_opts == true) &&
1728             ((tp->t_flags2 & TF2_DONT_SACK_QUEUE) == 0)) {
1729                 /*
1730                  * If there are other options (SACK?) and the
1731                  * tcp endpoint has not expressly told us it does
1732                  * not care about SACKS, then we should wake up.
1733                  */
1734                 *should_wake = true;
1735         } else if (*should_wake == false) {
1736                 /* Wakeup override check if we are false here  */
1737                 *should_wake = tcp_lro_check_wake_status(tp);
1738         }
1739         /* Is the ack compressable? */
1740         if (can_compress == false)
1741                 goto done;
1742         /* Does the TCP endpoint support ACK compression? */
1743         if ((tp->t_flags2 & TF2_MBUF_ACKCMP) == 0)
1744                 goto done;
1745
1746         /* Lets get the TOS/traffic class field */
1747         l3.ptr = mtod(m, void *);
1748         switch (lro_type) {
1749         case LRO_TYPE_IPV4_TCP:
1750                 iptos = l3.ip4->ip_tos;
1751                 break;
1752         case LRO_TYPE_IPV6_TCP:
1753                 iptos = IPV6_TRAFFIC_CLASS(l3.ip6);
1754                 break;
1755         default:
1756                 iptos = 0;      /* Keep compiler happy. */
1757                 break;
1758         }
1759         /* Now lets get space if we don't have some already */
1760         if (*cmp == NULL) {
1761 new_one:
1762                 nm = tcp_lro_get_last_if_ackcmp(lc, le, tp, &n_mbuf,
1763                     can_append_old_cmp);
1764                 if (__predict_false(nm == NULL))
1765                         goto done;
1766                 *cmp = nm;
1767                 if (n_mbuf) {
1768                         /*
1769                          *  Link in the new cmp ack to our in-order place,
1770                          * first set our cmp ack's next to where we are.
1771                          */
1772                         nm->m_nextpkt = m;
1773                         (*pp) = nm;
1774                         /*
1775                          * Set it up so mv_to is advanced to our
1776                          * compressed ack. This way the caller can
1777                          * advance pp to the right place.
1778                          */
1779                         *mv_to = nm;
1780                         /*
1781                          * Advance it here locally as well.
1782                          */
1783                         pp = &nm->m_nextpkt;
1784                 }
1785         } else {
1786                 /* We have one already we are working on */
1787                 nm = *cmp;
1788                 if (M_TRAILINGSPACE(nm) < sizeof(struct tcp_ackent)) {
1789                         /* We ran out of space */
1790                         tp->t_flags2 |= TF2_MBUF_L_ACKS;
1791                         goto new_one;
1792                 }
1793         }
1794         MPASS(M_TRAILINGSPACE(nm) >= sizeof(struct tcp_ackent));
1795         counter_u64_add(tcp_inp_lro_compressed, 1);
1796         le->compressed++;
1797         /* We can add in to the one on the tail */
1798         ack_ent = mtod(nm, struct tcp_ackent *);
1799         idx = (nm->m_len / sizeof(struct tcp_ackent));
1800         build_ack_entry(&ack_ent[idx], th, m, ts_ptr, iptos);
1801
1802         /* Bump the size of both pkt-hdr and len */
1803         nm->m_len += sizeof(struct tcp_ackent);
1804         nm->m_pkthdr.len += sizeof(struct tcp_ackent);
1805 compressed:
1806         /* Advance to next mbuf before freeing. */
1807         *pp = m->m_nextpkt;
1808         m->m_nextpkt = NULL;
1809         m_freem(m);
1810         return (true);
1811 done:
1812         counter_u64_add(tcp_uncomp_total, 1);
1813         le->uncompressed++;
1814         return (false);
1815 }
1816 #endif
1817
1818 static struct lro_head *
1819 tcp_lro_rx_get_bucket(struct lro_ctrl *lc, struct mbuf *m, struct lro_parser *parser)
1820 {
1821         u_long hash;
1822
1823         if (M_HASHTYPE_ISHASH(m)) {
1824                 hash = m->m_pkthdr.flowid;
1825         } else {
1826                 for (unsigned i = hash = 0; i != LRO_RAW_ADDRESS_MAX; i++)
1827                         hash += parser->data.raw[i];
1828         }
1829         return (&lc->lro_hash[hash % lc->lro_hashsz]);
1830 }
1831
1832 static int
1833 tcp_lro_rx_common(struct lro_ctrl *lc, struct mbuf *m, uint32_t csum, bool use_hash)
1834 {
1835         struct lro_parser pi;   /* inner address data */
1836         struct lro_parser po;   /* outer address data */
1837         struct lro_parser *pa;  /* current parser for TCP stream */
1838         struct lro_entry *le;
1839         struct lro_head *bucket;
1840         struct tcphdr *th;
1841         int tcp_data_len;
1842         int tcp_opt_len;
1843         int error;
1844         uint16_t tcp_data_sum;
1845
1846 #ifdef INET
1847         /* Quickly decide if packet cannot be LRO'ed */
1848         if (__predict_false(V_ipforwarding != 0))
1849                 return (TCP_LRO_CANNOT);
1850 #endif
1851 #ifdef INET6
1852         /* Quickly decide if packet cannot be LRO'ed */
1853         if (__predict_false(V_ip6_forwarding != 0))
1854                 return (TCP_LRO_CANNOT);
1855 #endif
1856         if (((m->m_pkthdr.csum_flags & (CSUM_DATA_VALID | CSUM_PSEUDO_HDR)) !=
1857              ((CSUM_DATA_VALID | CSUM_PSEUDO_HDR))) ||
1858             (m->m_pkthdr.csum_data != 0xffff)) {
1859                 /*
1860                  * The checksum either did not have hardware offload
1861                  * or it was a bad checksum. We can't LRO such
1862                  * a packet.
1863                  */
1864                 counter_u64_add(tcp_bad_csums, 1);
1865                 return (TCP_LRO_CANNOT);
1866         }
1867         /* We expect a contiguous header [eh, ip, tcp]. */
1868         pa = tcp_lro_parser(m, &po, &pi, true);
1869         if (__predict_false(pa == NULL))
1870                 return (TCP_LRO_NOT_SUPPORTED);
1871
1872         /* We don't expect any padding. */
1873         error = tcp_lro_trim_mbuf_chain(m, pa);
1874         if (__predict_false(error != 0))
1875                 return (error);
1876
1877 #ifdef INET
1878         switch (pa->data.lro_type) {
1879         case LRO_TYPE_IPV4_TCP:
1880                 error = tcp_lro_rx_ipv4(lc, m, pa->ip4);
1881                 if (__predict_false(error != 0))
1882                         return (error);
1883                 break;
1884         default:
1885                 break;
1886         }
1887 #endif
1888         /* If no hardware or arrival stamp on the packet add timestamp */
1889         if ((m->m_flags & (M_TSTMP_LRO | M_TSTMP)) == 0) {
1890                 m->m_pkthdr.rcv_tstmp = bintime2ns(&lc->lro_last_queue_time);
1891                 m->m_flags |= M_TSTMP_LRO;
1892         }
1893
1894         /* Get pointer to TCP header. */
1895         th = pa->tcp;
1896
1897         /* Don't process SYN packets. */
1898         if (__predict_false(tcp_get_flags(th) & TH_SYN))
1899                 return (TCP_LRO_CANNOT);
1900
1901         /* Get total TCP header length and compute payload length. */
1902         tcp_opt_len = (th->th_off << 2);
1903         tcp_data_len = m->m_pkthdr.len - ((uint8_t *)th -
1904             (uint8_t *)m->m_data) - tcp_opt_len;
1905         tcp_opt_len -= sizeof(*th);
1906
1907         /* Don't process invalid TCP headers. */
1908         if (__predict_false(tcp_opt_len < 0 || tcp_data_len < 0))
1909                 return (TCP_LRO_CANNOT);
1910
1911         /* Compute TCP data only checksum. */
1912         if (tcp_data_len == 0)
1913                 tcp_data_sum = 0;       /* no data, no checksum */
1914         else if (__predict_false(csum != 0))
1915                 tcp_data_sum = tcp_lro_rx_csum_data(pa, ~csum);
1916         else
1917                 tcp_data_sum = tcp_lro_rx_csum_data(pa, ~th->th_sum);
1918
1919         /* Save TCP info in mbuf. */
1920         m->m_nextpkt = NULL;
1921         m->m_pkthdr.rcvif = lc->ifp;
1922         m->m_pkthdr.lro_tcp_d_csum = tcp_data_sum;
1923         m->m_pkthdr.lro_tcp_d_len = tcp_data_len;
1924         m->m_pkthdr.lro_tcp_h_off = ((uint8_t *)th - (uint8_t *)m->m_data);
1925         m->m_pkthdr.lro_nsegs = 1;
1926
1927         /* Get hash bucket. */
1928         if (!use_hash) {
1929                 bucket = &lc->lro_hash[0];
1930         } else {
1931                 bucket = tcp_lro_rx_get_bucket(lc, m, pa);
1932         }
1933
1934         /* Try to find a matching previous segment. */
1935         LIST_FOREACH(le, bucket, hash_next) {
1936                 /* Compare addresses and ports. */
1937                 if (lro_address_compare(&po.data, &le->outer.data) == false ||
1938                     lro_address_compare(&pi.data, &le->inner.data) == false)
1939                         continue;
1940
1941                 /* Check if no data and old ACK. */
1942                 if (tcp_data_len == 0 &&
1943                     SEQ_LT(ntohl(th->th_ack), ntohl(le->ack_seq))) {
1944                         m_freem(m);
1945                         return (0);
1946                 }
1947
1948                 /* Mark "m" in the last spot. */
1949                 le->m_last_mbuf->m_nextpkt = m;
1950                 /* Now set the tail to "m". */
1951                 le->m_last_mbuf = m;
1952                 return (0);
1953         }
1954
1955         /* Try to find an empty slot. */
1956         if (LIST_EMPTY(&lc->lro_free))
1957                 return (TCP_LRO_NO_ENTRIES);
1958
1959         /* Start a new segment chain. */
1960         le = LIST_FIRST(&lc->lro_free);
1961         LIST_REMOVE(le, next);
1962         tcp_lro_active_insert(lc, bucket, le);
1963
1964         /* Make sure the headers are set. */
1965         le->inner = pi;
1966         le->outer = po;
1967
1968         /* Store time this entry was allocated. */
1969         le->alloc_time = lc->lro_last_queue_time;
1970
1971         tcp_set_entry_to_mbuf(lc, le, m, th);
1972
1973         /* Now set the tail to "m". */
1974         le->m_last_mbuf = m;
1975
1976         return (0);
1977 }
1978
1979 int
1980 tcp_lro_rx(struct lro_ctrl *lc, struct mbuf *m, uint32_t csum)
1981 {
1982         int error;
1983
1984         if (((m->m_pkthdr.csum_flags & (CSUM_DATA_VALID | CSUM_PSEUDO_HDR)) !=
1985              ((CSUM_DATA_VALID | CSUM_PSEUDO_HDR))) ||
1986             (m->m_pkthdr.csum_data != 0xffff)) {
1987                 /*
1988                  * The checksum either did not have hardware offload
1989                  * or it was a bad checksum. We can't LRO such
1990                  * a packet.
1991                  */
1992                 counter_u64_add(tcp_bad_csums, 1);
1993                 return (TCP_LRO_CANNOT);
1994         }
1995         /* get current time */
1996         binuptime(&lc->lro_last_queue_time);
1997         CURVNET_SET(lc->ifp->if_vnet);
1998         error = tcp_lro_rx_common(lc, m, csum, true);
1999         if (__predict_false(error != 0)) {
2000                 /*
2001                  * Flush anything we have acummulated
2002                  * ahead of this packet that can't
2003                  * be LRO'd. This preserves order.
2004                  */
2005                 tcp_lro_flush_active(lc);
2006         }
2007         CURVNET_RESTORE();
2008
2009         return (error);
2010 }
2011
2012 void
2013 tcp_lro_queue_mbuf(struct lro_ctrl *lc, struct mbuf *mb)
2014 {
2015         NET_EPOCH_ASSERT();
2016         /* sanity checks */
2017         if (__predict_false(lc->ifp == NULL || lc->lro_mbuf_data == NULL ||
2018             lc->lro_mbuf_max == 0)) {
2019                 /* packet drop */
2020                 m_freem(mb);
2021                 return;
2022         }
2023
2024         /* check if packet is not LRO capable */
2025         if (__predict_false((lc->ifp->if_capenable & IFCAP_LRO) == 0)) {
2026                 /* input packet to network layer */
2027                 (*lc->ifp->if_input) (lc->ifp, mb);
2028                 return;
2029         }
2030
2031         /* If no hardware or arrival stamp on the packet add timestamp */
2032         if ((tcplro_stacks_wanting_mbufq > 0) &&
2033             (tcp_less_accurate_lro_ts == 0) &&
2034             ((mb->m_flags & M_TSTMP) == 0)) {
2035                 /* Add in an LRO time since no hardware */
2036                 binuptime(&lc->lro_last_queue_time);
2037                 mb->m_pkthdr.rcv_tstmp = bintime2ns(&lc->lro_last_queue_time);
2038                 mb->m_flags |= M_TSTMP_LRO;
2039         }
2040
2041         /* create sequence number */
2042         lc->lro_mbuf_data[lc->lro_mbuf_count].seq =
2043             (((uint64_t)M_HASHTYPE_GET(mb)) << 56) |
2044             (((uint64_t)mb->m_pkthdr.flowid) << 24) |
2045             ((uint64_t)lc->lro_mbuf_count);
2046
2047         /* enter mbuf */
2048         lc->lro_mbuf_data[lc->lro_mbuf_count].mb = mb;
2049
2050         /* flush if array is full */
2051         if (__predict_false(++lc->lro_mbuf_count == lc->lro_mbuf_max))
2052                 tcp_lro_flush_all(lc);
2053 }
2054
2055 /* end */