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sys/netinet/tcp_lro.c
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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 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/sysctl.h> 48 49 #include <net/if.h> 50 #include <net/if_var.h> 51 #include <net/ethernet.h> 52 #include <net/vnet.h> 53 54 #include <netinet/in_systm.h> 55 #include <netinet/in.h> 56 #include <netinet/ip6.h> 57 #include <netinet/ip.h> 58 #include <netinet/ip_var.h> 59 #include <netinet/tcp.h> 60 #include <netinet/tcp_seq.h> 61 #include <netinet/tcp_lro.h> 62 #include <netinet/tcp_var.h> 63 64 #include <netinet6/ip6_var.h> 65 66 #include <machine/in_cksum.h> 67 68 static MALLOC_DEFINE(M_LRO, "LRO", "LRO control structures"); 69 70 #define TCP_LRO_UPDATE_CSUM 1 71 #ifndef TCP_LRO_UPDATE_CSUM 72 #define TCP_LRO_INVALID_CSUM 0x0000 73 #endif 74 75 static void tcp_lro_rx_done(struct lro_ctrl *lc); 76 static int tcp_lro_rx2(struct lro_ctrl *lc, struct mbuf *m, 77 uint32_t csum, int use_hash); 78 79 SYSCTL_NODE(_net_inet_tcp, OID_AUTO, lro, CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 80 "TCP LRO"); 81 82 static unsigned tcp_lro_entries = TCP_LRO_ENTRIES; 83 SYSCTL_UINT(_net_inet_tcp_lro, OID_AUTO, entries, 84 CTLFLAG_RDTUN | CTLFLAG_MPSAFE, &tcp_lro_entries, 0, 85 "default number of LRO entries"); 86 87 static __inline void 88 tcp_lro_active_insert(struct lro_ctrl *lc, struct lro_head *bucket, 89 struct lro_entry *le) 90 { 91 92 LIST_INSERT_HEAD(&lc->lro_active, le, next); 93 LIST_INSERT_HEAD(bucket, le, hash_next); 94 } 95 96 static __inline void 97 tcp_lro_active_remove(struct lro_entry *le) 98 { 99 100 LIST_REMOVE(le, next); /* active list */ 101 LIST_REMOVE(le, hash_next); /* hash bucket */ 102 } 103 104 int 105 tcp_lro_init(struct lro_ctrl *lc) 106 { 107 return (tcp_lro_init_args(lc, NULL, tcp_lro_entries, 0)); 108 } 109 110 int 111 tcp_lro_init_args(struct lro_ctrl *lc, struct ifnet *ifp, 112 unsigned lro_entries, unsigned lro_mbufs) 113 { 114 struct lro_entry *le; 115 size_t size; 116 unsigned i, elements; 117 118 lc->lro_bad_csum = 0; 119 lc->lro_queued = 0; 120 lc->lro_flushed = 0; 121 lc->lro_mbuf_count = 0; 122 lc->lro_mbuf_max = lro_mbufs; 123 lc->lro_cnt = lro_entries; 124 lc->lro_ackcnt_lim = TCP_LRO_ACKCNT_MAX; 125 lc->lro_length_lim = TCP_LRO_LENGTH_MAX; 126 lc->ifp = ifp; 127 LIST_INIT(&lc->lro_free); 128 LIST_INIT(&lc->lro_active); 129 130 /* create hash table to accelerate entry lookup */ 131 if (lro_entries > lro_mbufs) 132 elements = lro_entries; 133 else 134 elements = lro_mbufs; 135 lc->lro_hash = phashinit_flags(elements, M_LRO, &lc->lro_hashsz, 136 HASH_NOWAIT); 137 if (lc->lro_hash == NULL) { 138 memset(lc, 0, sizeof(*lc)); 139 return (ENOMEM); 140 } 141 142 /* compute size to allocate */ 143 size = (lro_mbufs * sizeof(struct lro_mbuf_sort)) + 144 (lro_entries * sizeof(*le)); 145 lc->lro_mbuf_data = (struct lro_mbuf_sort *) 146 malloc(size, M_LRO, M_NOWAIT | M_ZERO); 147 148 /* check for out of memory */ 149 if (lc->lro_mbuf_data == NULL) { 150 free(lc->lro_hash, M_LRO); 151 memset(lc, 0, sizeof(*lc)); 152 return (ENOMEM); 153 } 154 /* compute offset for LRO entries */ 155 le = (struct lro_entry *) 156 (lc->lro_mbuf_data + lro_mbufs); 157 158 /* setup linked list */ 159 for (i = 0; i != lro_entries; i++) 160 LIST_INSERT_HEAD(&lc->lro_free, le + i, next); 161 162 return (0); 163 } 164 165 void 166 tcp_lro_free(struct lro_ctrl *lc) 167 { 168 struct lro_entry *le; 169 unsigned x; 170 171 /* reset LRO free list */ 172 LIST_INIT(&lc->lro_free); 173 174 /* free active mbufs, if any */ 175 while ((le = LIST_FIRST(&lc->lro_active)) != NULL) { 176 tcp_lro_active_remove(le); 177 m_freem(le->m_head); 178 } 179 180 /* free hash table */ 181 free(lc->lro_hash, M_LRO); 182 lc->lro_hash = NULL; 183 lc->lro_hashsz = 0; 184 185 /* free mbuf array, if any */ 186 for (x = 0; x != lc->lro_mbuf_count; x++) 187 m_freem(lc->lro_mbuf_data[x].mb); 188 lc->lro_mbuf_count = 0; 189 190 /* free allocated memory, if any */ 191 free(lc->lro_mbuf_data, M_LRO); 192 lc->lro_mbuf_data = NULL; 193 } 194 195 #ifdef TCP_LRO_UPDATE_CSUM 196 static uint16_t 197 tcp_lro_csum_th(struct tcphdr *th) 198 { 199 uint32_t ch; 200 uint16_t *p, l; 201 202 ch = th->th_sum = 0x0000; 203 l = th->th_off; 204 p = (uint16_t *)th; 205 while (l > 0) { 206 ch += *p; 207 p++; 208 ch += *p; 209 p++; 210 l--; 211 } 212 while (ch > 0xffff) 213 ch = (ch >> 16) + (ch & 0xffff); 214 215 return (ch & 0xffff); 216 } 217 218 static uint16_t 219 tcp_lro_rx_csum_fixup(struct lro_entry *le, void *l3hdr, struct tcphdr *th, 220 uint16_t tcp_data_len, uint16_t csum) 221 { 222 uint32_t c; 223 uint16_t cs; 224 225 c = csum; 226 227 /* Remove length from checksum. */ 228 switch (le->eh_type) { 229 #ifdef INET6 230 case ETHERTYPE_IPV6: 231 { 232 struct ip6_hdr *ip6; 233 234 ip6 = (struct ip6_hdr *)l3hdr; 235 if (le->append_cnt == 0) 236 cs = ip6->ip6_plen; 237 else { 238 uint32_t cx; 239 240 cx = ntohs(ip6->ip6_plen); 241 cs = in6_cksum_pseudo(ip6, cx, ip6->ip6_nxt, 0); 242 } 243 break; 244 } 245 #endif 246 #ifdef INET 247 case ETHERTYPE_IP: 248 { 249 struct ip *ip4; 250 251 ip4 = (struct ip *)l3hdr; 252 if (le->append_cnt == 0) 253 cs = ip4->ip_len; 254 else { 255 cs = in_addword(ntohs(ip4->ip_len) - sizeof(*ip4), 256 IPPROTO_TCP); 257 cs = in_pseudo(ip4->ip_src.s_addr, ip4->ip_dst.s_addr, 258 htons(cs)); 259 } 260 break; 261 } 262 #endif 263 default: 264 cs = 0; /* Keep compiler happy. */ 265 } 266 267 cs = ~cs; 268 c += cs; 269 270 /* Remove TCP header csum. */ 271 cs = ~tcp_lro_csum_th(th); 272 c += cs; 273 while (c > 0xffff) 274 c = (c >> 16) + (c & 0xffff); 275 276 return (c & 0xffff); 277 } 278 #endif 279 280 static void 281 tcp_lro_rx_done(struct lro_ctrl *lc) 282 { 283 struct lro_entry *le; 284 285 while ((le = LIST_FIRST(&lc->lro_active)) != NULL) { 286 tcp_lro_active_remove(le); 287 tcp_lro_flush(lc, le); 288 } 289 } 290 291 void 292 tcp_lro_flush_inactive(struct lro_ctrl *lc, const struct timeval *timeout) 293 { 294 struct lro_entry *le, *le_tmp; 295 struct timeval tv; 296 297 if (LIST_EMPTY(&lc->lro_active)) 298 return; 299 300 getmicrotime(&tv); 301 timevalsub(&tv, timeout); 302 LIST_FOREACH_SAFE(le, &lc->lro_active, next, le_tmp) { 303 if (timevalcmp(&tv, &le->mtime, >=)) { 304 tcp_lro_active_remove(le); 305 tcp_lro_flush(lc, le); 306 } 307 } 308 } 309 310 void 311 tcp_lro_flush(struct lro_ctrl *lc, struct lro_entry *le) 312 { 313 314 if (le->append_cnt > 0) { 315 struct tcphdr *th; 316 uint16_t p_len; 317 318 p_len = htons(le->p_len); 319 switch (le->eh_type) { 320 #ifdef INET6 321 case ETHERTYPE_IPV6: 322 { 323 struct ip6_hdr *ip6; 324 325 ip6 = le->le_ip6; 326 ip6->ip6_plen = p_len; 327 th = (struct tcphdr *)(ip6 + 1); 328 le->m_head->m_pkthdr.csum_flags = CSUM_DATA_VALID | 329 CSUM_PSEUDO_HDR; 330 le->p_len += ETHER_HDR_LEN + sizeof(*ip6); 331 break; 332 } 333 #endif 334 #ifdef INET 335 case ETHERTYPE_IP: 336 { 337 struct ip *ip4; 338 #ifdef TCP_LRO_UPDATE_CSUM 339 uint32_t cl; 340 uint16_t c; 341 #endif 342 343 ip4 = le->le_ip4; 344 #ifdef TCP_LRO_UPDATE_CSUM 345 /* Fix IP header checksum for new length. */ 346 c = ~ip4->ip_sum; 347 cl = c; 348 c = ~ip4->ip_len; 349 cl += c + p_len; 350 while (cl > 0xffff) 351 cl = (cl >> 16) + (cl & 0xffff); 352 c = cl; 353 ip4->ip_sum = ~c; 354 #else 355 ip4->ip_sum = TCP_LRO_INVALID_CSUM; 356 #endif 357 ip4->ip_len = p_len; 358 th = (struct tcphdr *)(ip4 + 1); 359 le->m_head->m_pkthdr.csum_flags = CSUM_DATA_VALID | 360 CSUM_PSEUDO_HDR | CSUM_IP_CHECKED | CSUM_IP_VALID; 361 le->p_len += ETHER_HDR_LEN; 362 break; 363 } 364 #endif 365 default: 366 th = NULL; /* Keep compiler happy. */ 367 } 368 le->m_head->m_pkthdr.csum_data = 0xffff; 369 le->m_head->m_pkthdr.len = le->p_len; 370 371 /* Incorporate the latest ACK into the TCP header. */ 372 th->th_ack = le->ack_seq; 373 th->th_win = le->window; 374 /* Incorporate latest timestamp into the TCP header. */ 375 if (le->timestamp != 0) { 376 uint32_t *ts_ptr; 377 378 ts_ptr = (uint32_t *)(th + 1); 379 ts_ptr[1] = htonl(le->tsval); 380 ts_ptr[2] = le->tsecr; 381 } 382 #ifdef TCP_LRO_UPDATE_CSUM 383 /* Update the TCP header checksum. */ 384 le->ulp_csum += p_len; 385 le->ulp_csum += tcp_lro_csum_th(th); 386 while (le->ulp_csum > 0xffff) 387 le->ulp_csum = (le->ulp_csum >> 16) + 388 (le->ulp_csum & 0xffff); 389 th->th_sum = (le->ulp_csum & 0xffff); 390 th->th_sum = ~th->th_sum; 391 #else 392 th->th_sum = TCP_LRO_INVALID_CSUM; 393 #endif 394 } 395 396 le->m_head->m_pkthdr.lro_nsegs = le->append_cnt + 1; 397 (*lc->ifp->if_input)(lc->ifp, le->m_head); 398 lc->lro_queued += le->append_cnt + 1; 399 lc->lro_flushed++; 400 bzero(le, sizeof(*le)); 401 LIST_INSERT_HEAD(&lc->lro_free, le, next); 402 } 403 404 #ifdef HAVE_INLINE_FLSLL 405 #define tcp_lro_msb_64(x) (1ULL << (flsll(x) - 1)) 406 #else 407 static inline uint64_t 408 tcp_lro_msb_64(uint64_t x) 409 { 410 x |= (x >> 1); 411 x |= (x >> 2); 412 x |= (x >> 4); 413 x |= (x >> 8); 414 x |= (x >> 16); 415 x |= (x >> 32); 416 return (x & ~(x >> 1)); 417 } 418 #endif 419 420 /* 421 * The tcp_lro_sort() routine is comparable to qsort(), except it has 422 * a worst case complexity limit of O(MIN(N,64)*N), where N is the 423 * number of elements to sort and 64 is the number of sequence bits 424 * available. The algorithm is bit-slicing the 64-bit sequence number, 425 * sorting one bit at a time from the most significant bit until the 426 * least significant one, skipping the constant bits. This is 427 * typically called a radix sort. 428 */ 429 static void 430 tcp_lro_sort(struct lro_mbuf_sort *parray, uint32_t size) 431 { 432 struct lro_mbuf_sort temp; 433 uint64_t ones; 434 uint64_t zeros; 435 uint32_t x; 436 uint32_t y; 437 438 repeat: 439 /* for small arrays insertion sort is faster */ 440 if (size <= 12) { 441 for (x = 1; x < size; x++) { 442 temp = parray[x]; 443 for (y = x; y > 0 && temp.seq < parray[y - 1].seq; y--) 444 parray[y] = parray[y - 1]; 445 parray[y] = temp; 446 } 447 return; 448 } 449 450 /* compute sequence bits which are constant */ 451 ones = 0; 452 zeros = 0; 453 for (x = 0; x != size; x++) { 454 ones |= parray[x].seq; 455 zeros |= ~parray[x].seq; 456 } 457 458 /* compute bits which are not constant into "ones" */ 459 ones &= zeros; 460 if (ones == 0) 461 return; 462 463 /* pick the most significant bit which is not constant */ 464 ones = tcp_lro_msb_64(ones); 465 466 /* 467 * Move entries having cleared sequence bits to the beginning 468 * of the array: 469 */ 470 for (x = y = 0; y != size; y++) { 471 /* skip set bits */ 472 if (parray[y].seq & ones) 473 continue; 474 /* swap entries */ 475 temp = parray[x]; 476 parray[x] = parray[y]; 477 parray[y] = temp; 478 x++; 479 } 480 481 KASSERT(x != 0 && x != size, ("Memory is corrupted\n")); 482 483 /* sort zeros */ 484 tcp_lro_sort(parray, x); 485 486 /* sort ones */ 487 parray += x; 488 size -= x; 489 goto repeat; 490 } 491 492 void 493 tcp_lro_flush_all(struct lro_ctrl *lc) 494 { 495 uint64_t seq; 496 uint64_t nseq; 497 unsigned x; 498 499 /* check if no mbufs to flush */ 500 if (lc->lro_mbuf_count == 0) 501 goto done; 502 503 /* sort all mbufs according to stream */ 504 tcp_lro_sort(lc->lro_mbuf_data, lc->lro_mbuf_count); 505 506 /* input data into LRO engine, stream by stream */ 507 seq = 0; 508 for (x = 0; x != lc->lro_mbuf_count; x++) { 509 struct mbuf *mb; 510 511 /* get mbuf */ 512 mb = lc->lro_mbuf_data[x].mb; 513 514 /* get sequence number, masking away the packet index */ 515 nseq = lc->lro_mbuf_data[x].seq & (-1ULL << 24); 516 517 /* check for new stream */ 518 if (seq != nseq) { 519 seq = nseq; 520 521 /* flush active streams */ 522 tcp_lro_rx_done(lc); 523 } 524 525 /* add packet to LRO engine */ 526 if (tcp_lro_rx2(lc, mb, 0, 0) != 0) { 527 /* input packet to network layer */ 528 (*lc->ifp->if_input)(lc->ifp, mb); 529 lc->lro_queued++; 530 lc->lro_flushed++; 531 } 532 } 533 done: 534 /* flush active streams */ 535 tcp_lro_rx_done(lc); 536 537 lc->lro_mbuf_count = 0; 538 } 539 540 #ifdef INET6 541 static int 542 tcp_lro_rx_ipv6(struct lro_ctrl *lc, struct mbuf *m, struct ip6_hdr *ip6, 543 struct tcphdr **th) 544 { 545 546 /* XXX-BZ we should check the flow-label. */ 547 548 /* XXX-BZ We do not yet support ext. hdrs. */ 549 if (ip6->ip6_nxt != IPPROTO_TCP) 550 return (TCP_LRO_NOT_SUPPORTED); 551 552 /* Find the TCP header. */ 553 *th = (struct tcphdr *)(ip6 + 1); 554 555 return (0); 556 } 557 #endif 558 559 #ifdef INET 560 static int 561 tcp_lro_rx_ipv4(struct lro_ctrl *lc, struct mbuf *m, struct ip *ip4, 562 struct tcphdr **th) 563 { 564 int csum_flags; 565 uint16_t csum; 566 567 if (ip4->ip_p != IPPROTO_TCP) 568 return (TCP_LRO_NOT_SUPPORTED); 569 570 /* Ensure there are no options. */ 571 if ((ip4->ip_hl << 2) != sizeof (*ip4)) 572 return (TCP_LRO_CANNOT); 573 574 /* .. and the packet is not fragmented. */ 575 if (ip4->ip_off & htons(IP_MF|IP_OFFMASK)) 576 return (TCP_LRO_CANNOT); 577 578 /* Legacy IP has a header checksum that needs to be correct. */ 579 csum_flags = m->m_pkthdr.csum_flags; 580 if (csum_flags & CSUM_IP_CHECKED) { 581 if (__predict_false((csum_flags & CSUM_IP_VALID) == 0)) { 582 lc->lro_bad_csum++; 583 return (TCP_LRO_CANNOT); 584 } 585 } else { 586 csum = in_cksum_hdr(ip4); 587 if (__predict_false((csum) != 0)) { 588 lc->lro_bad_csum++; 589 return (TCP_LRO_CANNOT); 590 } 591 } 592 593 /* Find the TCP header (we assured there are no IP options). */ 594 *th = (struct tcphdr *)(ip4 + 1); 595 596 return (0); 597 } 598 #endif 599 600 static int 601 tcp_lro_rx2(struct lro_ctrl *lc, struct mbuf *m, uint32_t csum, int use_hash) 602 { 603 struct lro_entry *le; 604 struct ether_header *eh; 605 #ifdef INET6 606 struct ip6_hdr *ip6 = NULL; /* Keep compiler happy. */ 607 #endif 608 #ifdef INET 609 struct ip *ip4 = NULL; /* Keep compiler happy. */ 610 #endif 611 struct tcphdr *th; 612 void *l3hdr = NULL; /* Keep compiler happy. */ 613 uint32_t *ts_ptr; 614 tcp_seq seq; 615 int error, ip_len, l; 616 uint16_t eh_type, tcp_data_len; 617 struct lro_head *bucket; 618 int force_flush = 0; 619 620 /* We expect a contiguous header [eh, ip, tcp]. */ 621 622 eh = mtod(m, struct ether_header *); 623 eh_type = ntohs(eh->ether_type); 624 switch (eh_type) { 625 #ifdef INET6 626 case ETHERTYPE_IPV6: 627 { 628 CURVNET_SET(lc->ifp->if_vnet); 629 if (V_ip6_forwarding != 0) { 630 /* XXX-BZ stats but changing lro_ctrl is a problem. */ 631 CURVNET_RESTORE(); 632 return (TCP_LRO_CANNOT); 633 } 634 CURVNET_RESTORE(); 635 l3hdr = ip6 = (struct ip6_hdr *)(eh + 1); 636 error = tcp_lro_rx_ipv6(lc, m, ip6, &th); 637 if (error != 0) 638 return (error); 639 tcp_data_len = ntohs(ip6->ip6_plen); 640 ip_len = sizeof(*ip6) + tcp_data_len; 641 break; 642 } 643 #endif 644 #ifdef INET 645 case ETHERTYPE_IP: 646 { 647 CURVNET_SET(lc->ifp->if_vnet); 648 if (V_ipforwarding != 0) { 649 /* XXX-BZ stats but changing lro_ctrl is a problem. */ 650 CURVNET_RESTORE(); 651 return (TCP_LRO_CANNOT); 652 } 653 CURVNET_RESTORE(); 654 l3hdr = ip4 = (struct ip *)(eh + 1); 655 error = tcp_lro_rx_ipv4(lc, m, ip4, &th); 656 if (error != 0) 657 return (error); 658 ip_len = ntohs(ip4->ip_len); 659 tcp_data_len = ip_len - sizeof(*ip4); 660 break; 661 } 662 #endif 663 /* XXX-BZ what happens in case of VLAN(s)? */ 664 default: 665 return (TCP_LRO_NOT_SUPPORTED); 666 } 667 668 /* 669 * If the frame is padded beyond the end of the IP packet, then we must 670 * trim the extra bytes off. 671 */ 672 l = m->m_pkthdr.len - (ETHER_HDR_LEN + ip_len); 673 if (l != 0) { 674 if (l < 0) 675 /* Truncated packet. */ 676 return (TCP_LRO_CANNOT); 677 678 m_adj(m, -l); 679 } 680 681 /* 682 * Check TCP header constraints. 683 */ 684 /* Ensure no bits set besides ACK or PSH. */ 685 if ((th->th_flags & ~(TH_ACK | TH_PUSH)) != 0) { 686 if (th->th_flags & TH_SYN) 687 return (TCP_LRO_CANNOT); 688 /* 689 * Make sure that previously seen segements/ACKs are delivered 690 * before this segement, e.g. FIN. 691 */ 692 force_flush = 1; 693 } 694 695 /* XXX-BZ We lose a ACK|PUSH flag concatenating multiple segments. */ 696 /* XXX-BZ Ideally we'd flush on PUSH? */ 697 698 /* 699 * Check for timestamps. 700 * Since the only option we handle are timestamps, we only have to 701 * handle the simple case of aligned timestamps. 702 */ 703 l = (th->th_off << 2); 704 tcp_data_len -= l; 705 l -= sizeof(*th); 706 ts_ptr = (uint32_t *)(th + 1); 707 if (l != 0 && (__predict_false(l != TCPOLEN_TSTAMP_APPA) || 708 (*ts_ptr != ntohl(TCPOPT_NOP<<24|TCPOPT_NOP<<16| 709 TCPOPT_TIMESTAMP<<8|TCPOLEN_TIMESTAMP)))) { 710 /* 711 * Make sure that previously seen segements/ACKs are delivered 712 * before this segement. 713 */ 714 force_flush = 1; 715 } 716 717 /* If the driver did not pass in the checksum, set it now. */ 718 if (csum == 0x0000) 719 csum = th->th_sum; 720 721 seq = ntohl(th->th_seq); 722 723 if (!use_hash) { 724 bucket = &lc->lro_hash[0]; 725 } else if (M_HASHTYPE_ISHASH(m)) { 726 bucket = &lc->lro_hash[m->m_pkthdr.flowid % lc->lro_hashsz]; 727 } else { 728 uint32_t hash; 729 730 switch (eh_type) { 731 #ifdef INET 732 case ETHERTYPE_IP: 733 hash = ip4->ip_src.s_addr + ip4->ip_dst.s_addr; 734 break; 735 #endif 736 #ifdef INET6 737 case ETHERTYPE_IPV6: 738 hash = ip6->ip6_src.s6_addr32[0] + 739 ip6->ip6_dst.s6_addr32[0]; 740 hash += ip6->ip6_src.s6_addr32[1] + 741 ip6->ip6_dst.s6_addr32[1]; 742 hash += ip6->ip6_src.s6_addr32[2] + 743 ip6->ip6_dst.s6_addr32[2]; 744 hash += ip6->ip6_src.s6_addr32[3] + 745 ip6->ip6_dst.s6_addr32[3]; 746 break; 747 #endif 748 default: 749 hash = 0; 750 break; 751 } 752 hash += th->th_sport + th->th_dport; 753 bucket = &lc->lro_hash[hash % lc->lro_hashsz]; 754 } 755 756 /* Try to find a matching previous segment. */ 757 LIST_FOREACH(le, bucket, hash_next) { 758 if (le->eh_type != eh_type) 759 continue; 760 if (le->source_port != th->th_sport || 761 le->dest_port != th->th_dport) 762 continue; 763 switch (eh_type) { 764 #ifdef INET6 765 case ETHERTYPE_IPV6: 766 if (bcmp(&le->source_ip6, &ip6->ip6_src, 767 sizeof(struct in6_addr)) != 0 || 768 bcmp(&le->dest_ip6, &ip6->ip6_dst, 769 sizeof(struct in6_addr)) != 0) 770 continue; 771 break; 772 #endif 773 #ifdef INET 774 case ETHERTYPE_IP: 775 if (le->source_ip4 != ip4->ip_src.s_addr || 776 le->dest_ip4 != ip4->ip_dst.s_addr) 777 continue; 778 break; 779 #endif 780 } 781 782 if (force_flush) { 783 /* Timestamps mismatch; this is a FIN, etc */ 784 tcp_lro_active_remove(le); 785 tcp_lro_flush(lc, le); 786 return (TCP_LRO_CANNOT); 787 } 788 789 /* Flush now if appending will result in overflow. */ 790 if (le->p_len > (lc->lro_length_lim - tcp_data_len)) { 791 tcp_lro_active_remove(le); 792 tcp_lro_flush(lc, le); 793 break; 794 } 795 796 /* Try to append the new segment. */ 797 if (__predict_false(seq != le->next_seq || 798 (tcp_data_len == 0 && 799 le->ack_seq == th->th_ack && 800 le->window == th->th_win))) { 801 /* Out of order packet or duplicate ACK. */ 802 tcp_lro_active_remove(le); 803 tcp_lro_flush(lc, le); 804 return (TCP_LRO_CANNOT); 805 } 806 807 if (l != 0) { 808 uint32_t tsval = ntohl(*(ts_ptr + 1)); 809 /* Make sure timestamp values are increasing. */ 810 /* XXX-BZ flip and use TSTMP_GEQ macro for this? */ 811 if (__predict_false(le->tsval > tsval || 812 *(ts_ptr + 2) == 0)) 813 return (TCP_LRO_CANNOT); 814 le->tsval = tsval; 815 le->tsecr = *(ts_ptr + 2); 816 } 817 if (tcp_data_len || SEQ_GT(ntohl(th->th_ack), ntohl(le->ack_seq))) { 818 le->next_seq += tcp_data_len; 819 le->ack_seq = th->th_ack; 820 le->window = th->th_win; 821 le->append_cnt++; 822 } else if (th->th_ack == le->ack_seq) { 823 le->window = WIN_MAX(le->window, th->th_win); 824 le->append_cnt++; 825 } else { 826 /* no data and old ack */ 827 le->append_cnt++; 828 m_freem(m); 829 return (0); 830 } 831 #ifdef TCP_LRO_UPDATE_CSUM 832 le->ulp_csum += tcp_lro_rx_csum_fixup(le, l3hdr, th, 833 tcp_data_len, ~csum); 834 #endif 835 836 if (tcp_data_len == 0) { 837 m_freem(m); 838 /* 839 * Flush this LRO entry, if this ACK should not 840 * be further delayed. 841 */ 842 if (le->append_cnt >= lc->lro_ackcnt_lim) { 843 tcp_lro_active_remove(le); 844 tcp_lro_flush(lc, le); 845 } 846 return (0); 847 } 848 849 le->p_len += tcp_data_len; 850 851 /* 852 * Adjust the mbuf so that m_data points to the first byte of 853 * the ULP payload. Adjust the mbuf to avoid complications and 854 * append new segment to existing mbuf chain. 855 */ 856 m_adj(m, m->m_pkthdr.len - tcp_data_len); 857 m_demote_pkthdr(m); 858 859 le->m_tail->m_next = m; 860 le->m_tail = m_last(m); 861 862 /* 863 * If a possible next full length packet would cause an 864 * overflow, pro-actively flush now. 865 */ 866 if (le->p_len > (lc->lro_length_lim - lc->ifp->if_mtu)) { 867 tcp_lro_active_remove(le); 868 tcp_lro_flush(lc, le); 869 } else 870 getmicrotime(&le->mtime); 871 872 return (0); 873 } 874 875 if (force_flush) { 876 /* 877 * Nothing to flush, but this segment can not be further 878 * aggregated/delayed. 879 */ 880 return (TCP_LRO_CANNOT); 881 } 882 883 /* Try to find an empty slot. */ 884 if (LIST_EMPTY(&lc->lro_free)) 885 return (TCP_LRO_NO_ENTRIES); 886 887 /* Start a new segment chain. */ 888 le = LIST_FIRST(&lc->lro_free); 889 LIST_REMOVE(le, next); 890 tcp_lro_active_insert(lc, bucket, le); 891 getmicrotime(&le->mtime); 892 893 /* Start filling in details. */ 894 switch (eh_type) { 895 #ifdef INET6 896 case ETHERTYPE_IPV6: 897 le->le_ip6 = ip6; 898 le->source_ip6 = ip6->ip6_src; 899 le->dest_ip6 = ip6->ip6_dst; 900 le->eh_type = eh_type; 901 le->p_len = m->m_pkthdr.len - ETHER_HDR_LEN - sizeof(*ip6); 902 break; 903 #endif 904 #ifdef INET 905 case ETHERTYPE_IP: 906 le->le_ip4 = ip4; 907 le->source_ip4 = ip4->ip_src.s_addr; 908 le->dest_ip4 = ip4->ip_dst.s_addr; 909 le->eh_type = eh_type; 910 le->p_len = m->m_pkthdr.len - ETHER_HDR_LEN; 911 break; 912 #endif 913 } 914 le->source_port = th->th_sport; 915 le->dest_port = th->th_dport; 916 917 le->next_seq = seq + tcp_data_len; 918 le->ack_seq = th->th_ack; 919 le->window = th->th_win; 920 if (l != 0) { 921 le->timestamp = 1; 922 le->tsval = ntohl(*(ts_ptr + 1)); 923 le->tsecr = *(ts_ptr + 2); 924 } 925 926 #ifdef TCP_LRO_UPDATE_CSUM 927 /* 928 * Do not touch the csum of the first packet. However save the 929 * "adjusted" checksum of just the source and destination addresses, 930 * the next header and the TCP payload. The length and TCP header 931 * parts may change, so we remove those from the saved checksum and 932 * re-add with final values on tcp_lro_flush() if needed. 933 */ 934 KASSERT(le->ulp_csum == 0, ("%s: le=%p le->ulp_csum=0x%04x\n", 935 __func__, le, le->ulp_csum)); 936 937 le->ulp_csum = tcp_lro_rx_csum_fixup(le, l3hdr, th, tcp_data_len, 938 ~csum); 939 th->th_sum = csum; /* Restore checksum on first packet. */ 940 #endif 941 942 le->m_head = m; 943 le->m_tail = m_last(m); 944 945 return (0); 946 } 947 948 int 949 tcp_lro_rx(struct lro_ctrl *lc, struct mbuf *m, uint32_t csum) 950 { 951 952 return tcp_lro_rx2(lc, m, csum, 1); 953 } 954 955 void 956 tcp_lro_queue_mbuf(struct lro_ctrl *lc, struct mbuf *mb) 957 { 958 /* sanity checks */ 959 if (__predict_false(lc->ifp == NULL || lc->lro_mbuf_data == NULL || 960 lc->lro_mbuf_max == 0)) { 961 /* packet drop */ 962 m_freem(mb); 963 return; 964 } 965 966 /* check if packet is not LRO capable */ 967 if (__predict_false(mb->m_pkthdr.csum_flags == 0 || 968 (lc->ifp->if_capenable & IFCAP_LRO) == 0)) { 969 970 /* input packet to network layer */ 971 (*lc->ifp->if_input) (lc->ifp, mb); 972 return; 973 } 974 975 /* create sequence number */ 976 lc->lro_mbuf_data[lc->lro_mbuf_count].seq = 977 (((uint64_t)M_HASHTYPE_GET(mb)) << 56) | 978 (((uint64_t)mb->m_pkthdr.flowid) << 24) | 979 ((uint64_t)lc->lro_mbuf_count); 980 981 /* enter mbuf */ 982 lc->lro_mbuf_data[lc->lro_mbuf_count].mb = mb; 983 984 /* flush if array is full */ 985 if (__predict_false(++lc->lro_mbuf_count == lc->lro_mbuf_max)) 986 tcp_lro_flush_all(lc); 987 } 988 989 /* end */
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