1 /* 2 * IPv6 output functions 3 * Linux INET6 implementation 4 * 5 * Authors: 6 * Pedro Roque <roque@di.fc.ul.pt> 7 * 8 * $Id: ip6_output.c,v 1.34 2002/02/01 22:01:04 davem Exp $ 9 * 10 * Based on linux/net/ipv4/ip_output.c 11 * 12 * This program is free software; you can redistribute it and/or 13 * modify it under the terms of the GNU General Public License 14 * as published by the Free Software Foundation; either version 15 * 2 of the License, or (at your option) any later version. 16 * 17 * Changes: 18 * A.N.Kuznetsov : airthmetics in fragmentation. 19 * extension headers are implemented. 20 * route changes now work. 21 * ip6_forward does not confuse sniffers. 22 * etc. 23 * 24 * H. von Brand : Added missing #include <linux/string.h> 25 * Imran Patel : frag id should be in NBO 26 * Kazunori MIYAZAWA @USAGI 27 * : add ip6_append_data and related functions 28 * for datagram xmit 29 */ 30 31 #include <linux/errno.h> 32 #include <linux/types.h> 33 #include <linux/string.h> 34 #include <linux/socket.h> 35 #include <linux/net.h> 36 #include <linux/netdevice.h> 37 #include <linux/if_arp.h> 38 #include <linux/in6.h> 39 #include <linux/tcp.h> 40 #include <linux/route.h> 41 #include <linux/module.h> 42 43 #include <linux/netfilter.h> 44 #include <linux/netfilter_ipv6.h> 45 46 #include <net/sock.h> 47 #include <net/snmp.h> 48 49 #include <net/ipv6.h> 50 #include <net/ndisc.h> 51 #include <net/protocol.h> 52 #include <net/ip6_route.h> 53 #include <net/addrconf.h> 54 #include <net/rawv6.h> 55 #include <net/icmp.h> 56 #include <net/xfrm.h> 57 #include <net/checksum.h> 58 59 static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)); 60 61 static __inline__ void ipv6_select_ident(struct sk_buff *skb, struct frag_hdr *fhdr) 62 { 63 static u32 ipv6_fragmentation_id = 1; 64 static DEFINE_SPINLOCK(ip6_id_lock); 65 66 spin_lock_bh(&ip6_id_lock); 67 fhdr->identification = htonl(ipv6_fragmentation_id); 68 if (++ipv6_fragmentation_id == 0) 69 ipv6_fragmentation_id = 1; 70 spin_unlock_bh(&ip6_id_lock); 71 } 72 73 static inline int ip6_output_finish(struct sk_buff *skb) 74 { 75 76 struct dst_entry *dst = skb->dst; 77 struct hh_cache *hh = dst->hh; 78 79 if (hh) { 80 int hh_alen; 81 82 read_lock_bh(&hh->hh_lock); 83 hh_alen = HH_DATA_ALIGN(hh->hh_len); 84 memcpy(skb->data - hh_alen, hh->hh_data, hh_alen); 85 read_unlock_bh(&hh->hh_lock); 86 skb_push(skb, hh->hh_len); 87 return hh->hh_output(skb); 88 } else if (dst->neighbour) 89 return dst->neighbour->output(skb); 90 91 IP6_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES); 92 kfree_skb(skb); 93 return -EINVAL; 94 95 } 96 97 /* dev_loopback_xmit for use with netfilter. */ 98 static int ip6_dev_loopback_xmit(struct sk_buff *newskb) 99 { 100 newskb->mac.raw = newskb->data; 101 __skb_pull(newskb, newskb->nh.raw - newskb->data); 102 newskb->pkt_type = PACKET_LOOPBACK; 103 newskb->ip_summed = CHECKSUM_UNNECESSARY; 104 BUG_TRAP(newskb->dst); 105 106 netif_rx(newskb); 107 return 0; 108 } 109 110 111 static int ip6_output2(struct sk_buff *skb) 112 { 113 struct dst_entry *dst = skb->dst; 114 struct net_device *dev = dst->dev; 115 116 skb->protocol = htons(ETH_P_IPV6); 117 skb->dev = dev; 118 119 if (ipv6_addr_is_multicast(&skb->nh.ipv6h->daddr)) { 120 struct ipv6_pinfo* np = skb->sk ? inet6_sk(skb->sk) : NULL; 121 122 if (!(dev->flags & IFF_LOOPBACK) && (!np || np->mc_loop) && 123 ipv6_chk_mcast_addr(dev, &skb->nh.ipv6h->daddr, 124 &skb->nh.ipv6h->saddr)) { 125 struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); 126 127 /* Do not check for IFF_ALLMULTI; multicast routing 128 is not supported in any case. 129 */ 130 if (newskb) 131 NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, newskb, NULL, 132 newskb->dev, 133 ip6_dev_loopback_xmit); 134 135 if (skb->nh.ipv6h->hop_limit == 0) { 136 IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS); 137 kfree_skb(skb); 138 return 0; 139 } 140 } 141 142 IP6_INC_STATS(IPSTATS_MIB_OUTMCASTPKTS); 143 } 144 145 return NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, skb,NULL, skb->dev,ip6_output_finish); 146 } 147 148 int ip6_output(struct sk_buff *skb) 149 { 150 if ((skb->len > dst_mtu(skb->dst) && !skb_is_gso(skb)) || 151 dst_allfrag(skb->dst)) 152 return ip6_fragment(skb, ip6_output2); 153 else 154 return ip6_output2(skb); 155 } 156 157 /* 158 * xmit an sk_buff (used by TCP) 159 */ 160 161 int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl, 162 struct ipv6_txoptions *opt, int ipfragok) 163 { 164 struct ipv6_pinfo *np = inet6_sk(sk); 165 struct in6_addr *first_hop = &fl->fl6_dst; 166 struct dst_entry *dst = skb->dst; 167 struct ipv6hdr *hdr; 168 u8 proto = fl->proto; 169 int seg_len = skb->len; 170 int hlimit, tclass; 171 u32 mtu; 172 173 if (opt) { 174 int head_room; 175 176 /* First: exthdrs may take lots of space (~8K for now) 177 MAX_HEADER is not enough. 178 */ 179 head_room = opt->opt_nflen + opt->opt_flen; 180 seg_len += head_room; 181 head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev); 182 183 if (skb_headroom(skb) < head_room) { 184 struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room); 185 kfree_skb(skb); 186 skb = skb2; 187 if (skb == NULL) { 188 IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS); 189 return -ENOBUFS; 190 } 191 if (sk) 192 skb_set_owner_w(skb, sk); 193 } 194 if (opt->opt_flen) 195 ipv6_push_frag_opts(skb, opt, &proto); 196 if (opt->opt_nflen) 197 ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop); 198 } 199 200 hdr = skb->nh.ipv6h = (struct ipv6hdr*)skb_push(skb, sizeof(struct ipv6hdr)); 201 202 /* 203 * Fill in the IPv6 header 204 */ 205 206 hlimit = -1; 207 if (np) 208 hlimit = np->hop_limit; 209 if (hlimit < 0) 210 hlimit = dst_metric(dst, RTAX_HOPLIMIT); 211 if (hlimit < 0) 212 hlimit = ipv6_get_hoplimit(dst->dev); 213 214 tclass = -1; 215 if (np) 216 tclass = np->tclass; 217 if (tclass < 0) 218 tclass = 0; 219 220 *(u32 *)hdr = htonl(0x60000000 | (tclass << 20)) | fl->fl6_flowlabel; 221 222 hdr->payload_len = htons(seg_len); 223 hdr->nexthdr = proto; 224 hdr->hop_limit = hlimit; 225 226 ipv6_addr_copy(&hdr->saddr, &fl->fl6_src); 227 ipv6_addr_copy(&hdr->daddr, first_hop); 228 229 skb->priority = sk->sk_priority; 230 231 mtu = dst_mtu(dst); 232 if ((skb->len <= mtu) || ipfragok || skb_is_gso(skb)) { 233 IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS); 234 return NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, 235 dst_output); 236 } 237 238 if (net_ratelimit()) 239 printk(KERN_DEBUG "IPv6: sending pkt_too_big to self\n"); 240 skb->dev = dst->dev; 241 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev); 242 IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS); 243 kfree_skb(skb); 244 return -EMSGSIZE; 245 } 246 247 /* 248 * To avoid extra problems ND packets are send through this 249 * routine. It's code duplication but I really want to avoid 250 * extra checks since ipv6_build_header is used by TCP (which 251 * is for us performance critical) 252 */ 253 254 int ip6_nd_hdr(struct sock *sk, struct sk_buff *skb, struct net_device *dev, 255 struct in6_addr *saddr, struct in6_addr *daddr, 256 int proto, int len) 257 { 258 struct ipv6_pinfo *np = inet6_sk(sk); 259 struct ipv6hdr *hdr; 260 int totlen; 261 262 skb->protocol = htons(ETH_P_IPV6); 263 skb->dev = dev; 264 265 totlen = len + sizeof(struct ipv6hdr); 266 267 hdr = (struct ipv6hdr *) skb_put(skb, sizeof(struct ipv6hdr)); 268 skb->nh.ipv6h = hdr; 269 270 *(u32*)hdr = htonl(0x60000000); 271 272 hdr->payload_len = htons(len); 273 hdr->nexthdr = proto; 274 hdr->hop_limit = np->hop_limit; 275 276 ipv6_addr_copy(&hdr->saddr, saddr); 277 ipv6_addr_copy(&hdr->daddr, daddr); 278 279 return 0; 280 } 281 282 static int ip6_call_ra_chain(struct sk_buff *skb, int sel) 283 { 284 struct ip6_ra_chain *ra; 285 struct sock *last = NULL; 286 287 read_lock(&ip6_ra_lock); 288 for (ra = ip6_ra_chain; ra; ra = ra->next) { 289 struct sock *sk = ra->sk; 290 if (sk && ra->sel == sel && 291 (!sk->sk_bound_dev_if || 292 sk->sk_bound_dev_if == skb->dev->ifindex)) { 293 if (last) { 294 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 295 if (skb2) 296 rawv6_rcv(last, skb2); 297 } 298 last = sk; 299 } 300 } 301 302 if (last) { 303 rawv6_rcv(last, skb); 304 read_unlock(&ip6_ra_lock); 305 return 1; 306 } 307 read_unlock(&ip6_ra_lock); 308 return 0; 309 } 310 311 static int ip6_forward_proxy_check(struct sk_buff *skb) 312 { 313 struct ipv6hdr *hdr = skb->nh.ipv6h; 314 u8 nexthdr = hdr->nexthdr; 315 int offset; 316 317 if (ipv6_ext_hdr(nexthdr)) { 318 offset = ipv6_skip_exthdr(skb, sizeof(*hdr), &nexthdr); 319 if (offset < 0) 320 return 0; 321 } else 322 offset = sizeof(struct ipv6hdr); 323 324 if (nexthdr == IPPROTO_ICMPV6) { 325 struct icmp6hdr *icmp6; 326 327 if (!pskb_may_pull(skb, skb->nh.raw + offset + 1 - skb->data)) 328 return 0; 329 330 icmp6 = (struct icmp6hdr *)(skb->nh.raw + offset); 331 332 switch (icmp6->icmp6_type) { 333 case NDISC_ROUTER_SOLICITATION: 334 case NDISC_ROUTER_ADVERTISEMENT: 335 case NDISC_NEIGHBOUR_SOLICITATION: 336 case NDISC_NEIGHBOUR_ADVERTISEMENT: 337 case NDISC_REDIRECT: 338 /* For reaction involving unicast neighbor discovery 339 * message destined to the proxied address, pass it to 340 * input function. 341 */ 342 return 1; 343 default: 344 break; 345 } 346 } 347 348 /* 349 * The proxying router can't forward traffic sent to a link-local 350 * address, so signal the sender and discard the packet. This 351 * behavior is clarified by the MIPv6 specification. 352 */ 353 if (ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) { 354 dst_link_failure(skb); 355 return -1; 356 } 357 358 return 0; 359 } 360 361 static inline int ip6_forward_finish(struct sk_buff *skb) 362 { 363 return dst_output(skb); 364 } 365 366 int ip6_forward(struct sk_buff *skb) 367 { 368 struct dst_entry *dst = skb->dst; 369 struct ipv6hdr *hdr = skb->nh.ipv6h; 370 struct inet6_skb_parm *opt = IP6CB(skb); 371 372 if (ipv6_devconf.forwarding == 0) 373 goto error; 374 375 if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) { 376 IP6_INC_STATS(IPSTATS_MIB_INDISCARDS); 377 goto drop; 378 } 379 380 skb->ip_summed = CHECKSUM_NONE; 381 382 /* 383 * We DO NOT make any processing on 384 * RA packets, pushing them to user level AS IS 385 * without ane WARRANTY that application will be able 386 * to interpret them. The reason is that we 387 * cannot make anything clever here. 388 * 389 * We are not end-node, so that if packet contains 390 * AH/ESP, we cannot make anything. 391 * Defragmentation also would be mistake, RA packets 392 * cannot be fragmented, because there is no warranty 393 * that different fragments will go along one path. --ANK 394 */ 395 if (opt->ra) { 396 u8 *ptr = skb->nh.raw + opt->ra; 397 if (ip6_call_ra_chain(skb, (ptr[2]<<8) + ptr[3])) 398 return 0; 399 } 400 401 /* 402 * check and decrement ttl 403 */ 404 if (hdr->hop_limit <= 1) { 405 /* Force OUTPUT device used as source address */ 406 skb->dev = dst->dev; 407 icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, 408 0, skb->dev); 409 IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS); 410 411 kfree_skb(skb); 412 return -ETIMEDOUT; 413 } 414 415 /* XXX: idev->cnf.proxy_ndp? */ 416 if (ipv6_devconf.proxy_ndp && 417 pneigh_lookup(&nd_tbl, &hdr->daddr, skb->dev, 0)) { 418 int proxied = ip6_forward_proxy_check(skb); 419 if (proxied > 0) 420 return ip6_input(skb); 421 else if (proxied < 0) { 422 IP6_INC_STATS(IPSTATS_MIB_INDISCARDS); 423 goto drop; 424 } 425 } 426 427 if (!xfrm6_route_forward(skb)) { 428 IP6_INC_STATS(IPSTATS_MIB_INDISCARDS); 429 goto drop; 430 } 431 dst = skb->dst; 432 433 /* IPv6 specs say nothing about it, but it is clear that we cannot 434 send redirects to source routed frames. 435 */ 436 if (skb->dev == dst->dev && dst->neighbour && opt->srcrt == 0) { 437 struct in6_addr *target = NULL; 438 struct rt6_info *rt; 439 struct neighbour *n = dst->neighbour; 440 441 /* 442 * incoming and outgoing devices are the same 443 * send a redirect. 444 */ 445 446 rt = (struct rt6_info *) dst; 447 if ((rt->rt6i_flags & RTF_GATEWAY)) 448 target = (struct in6_addr*)&n->primary_key; 449 else 450 target = &hdr->daddr; 451 452 /* Limit redirects both by destination (here) 453 and by source (inside ndisc_send_redirect) 454 */ 455 if (xrlim_allow(dst, 1*HZ)) 456 ndisc_send_redirect(skb, n, target); 457 } else if (ipv6_addr_type(&hdr->saddr)&(IPV6_ADDR_MULTICAST|IPV6_ADDR_LOOPBACK 458 |IPV6_ADDR_LINKLOCAL)) { 459 /* This check is security critical. */ 460 goto error; 461 } 462 463 if (skb->len > dst_mtu(dst)) { 464 /* Again, force OUTPUT device used as source address */ 465 skb->dev = dst->dev; 466 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, dst_mtu(dst), skb->dev); 467 IP6_INC_STATS_BH(IPSTATS_MIB_INTOOBIGERRORS); 468 IP6_INC_STATS_BH(IPSTATS_MIB_FRAGFAILS); 469 kfree_skb(skb); 470 return -EMSGSIZE; 471 } 472 473 if (skb_cow(skb, dst->dev->hard_header_len)) { 474 IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS); 475 goto drop; 476 } 477 478 hdr = skb->nh.ipv6h; 479 480 /* Mangling hops number delayed to point after skb COW */ 481 482 hdr->hop_limit--; 483 484 IP6_INC_STATS_BH(IPSTATS_MIB_OUTFORWDATAGRAMS); 485 return NF_HOOK(PF_INET6,NF_IP6_FORWARD, skb, skb->dev, dst->dev, ip6_forward_finish); 486 487 error: 488 IP6_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS); 489 drop: 490 kfree_skb(skb); 491 return -EINVAL; 492 } 493 494 static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from) 495 { 496 to->pkt_type = from->pkt_type; 497 to->priority = from->priority; 498 to->protocol = from->protocol; 499 dst_release(to->dst); 500 to->dst = dst_clone(from->dst); 501 to->dev = from->dev; 502 503 #ifdef CONFIG_NET_SCHED 504 to->tc_index = from->tc_index; 505 #endif 506 #ifdef CONFIG_NETFILTER 507 to->nfmark = from->nfmark; 508 /* Connection association is same as pre-frag packet */ 509 nf_conntrack_put(to->nfct); 510 to->nfct = from->nfct; 511 nf_conntrack_get(to->nfct); 512 to->nfctinfo = from->nfctinfo; 513 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) 514 nf_conntrack_put_reasm(to->nfct_reasm); 515 to->nfct_reasm = from->nfct_reasm; 516 nf_conntrack_get_reasm(to->nfct_reasm); 517 #endif 518 #ifdef CONFIG_BRIDGE_NETFILTER 519 nf_bridge_put(to->nf_bridge); 520 to->nf_bridge = from->nf_bridge; 521 nf_bridge_get(to->nf_bridge); 522 #endif 523 #endif 524 skb_copy_secmark(to, from); 525 } 526 527 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) 528 { 529 u16 offset = sizeof(struct ipv6hdr); 530 struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr*)(skb->nh.ipv6h + 1); 531 unsigned int packet_len = skb->tail - skb->nh.raw; 532 int found_rhdr = 0; 533 *nexthdr = &skb->nh.ipv6h->nexthdr; 534 535 while (offset + 1 <= packet_len) { 536 537 switch (**nexthdr) { 538 539 case NEXTHDR_HOP: 540 break; 541 case NEXTHDR_ROUTING: 542 found_rhdr = 1; 543 break; 544 case NEXTHDR_DEST: 545 #ifdef CONFIG_IPV6_MIP6 546 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) 547 break; 548 #endif 549 if (found_rhdr) 550 return offset; 551 break; 552 default : 553 return offset; 554 } 555 556 offset += ipv6_optlen(exthdr); 557 *nexthdr = &exthdr->nexthdr; 558 exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset); 559 } 560 561 return offset; 562 } 563 EXPORT_SYMBOL_GPL(ip6_find_1stfragopt); 564 565 static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)) 566 { 567 struct net_device *dev; 568 struct sk_buff *frag; 569 struct rt6_info *rt = (struct rt6_info*)skb->dst; 570 struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL; 571 struct ipv6hdr *tmp_hdr; 572 struct frag_hdr *fh; 573 unsigned int mtu, hlen, left, len; 574 u32 frag_id = 0; 575 int ptr, offset = 0, err=0; 576 u8 *prevhdr, nexthdr = 0; 577 578 dev = rt->u.dst.dev; 579 hlen = ip6_find_1stfragopt(skb, &prevhdr); 580 nexthdr = *prevhdr; 581 582 mtu = dst_mtu(&rt->u.dst); 583 if (np && np->frag_size < mtu) { 584 if (np->frag_size) 585 mtu = np->frag_size; 586 } 587 mtu -= hlen + sizeof(struct frag_hdr); 588 589 if (skb_shinfo(skb)->frag_list) { 590 int first_len = skb_pagelen(skb); 591 592 if (first_len - hlen > mtu || 593 ((first_len - hlen) & 7) || 594 skb_cloned(skb)) 595 goto slow_path; 596 597 for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next) { 598 /* Correct geometry. */ 599 if (frag->len > mtu || 600 ((frag->len & 7) && frag->next) || 601 skb_headroom(frag) < hlen) 602 goto slow_path; 603 604 /* Partially cloned skb? */ 605 if (skb_shared(frag)) 606 goto slow_path; 607 608 BUG_ON(frag->sk); 609 if (skb->sk) { 610 sock_hold(skb->sk); 611 frag->sk = skb->sk; 612 frag->destructor = sock_wfree; 613 skb->truesize -= frag->truesize; 614 } 615 } 616 617 err = 0; 618 offset = 0; 619 frag = skb_shinfo(skb)->frag_list; 620 skb_shinfo(skb)->frag_list = NULL; 621 /* BUILD HEADER */ 622 623 tmp_hdr = kmalloc(hlen, GFP_ATOMIC); 624 if (!tmp_hdr) { 625 IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS); 626 return -ENOMEM; 627 } 628 629 *prevhdr = NEXTHDR_FRAGMENT; 630 memcpy(tmp_hdr, skb->nh.raw, hlen); 631 __skb_pull(skb, hlen); 632 fh = (struct frag_hdr*)__skb_push(skb, sizeof(struct frag_hdr)); 633 skb->nh.raw = __skb_push(skb, hlen); 634 memcpy(skb->nh.raw, tmp_hdr, hlen); 635 636 ipv6_select_ident(skb, fh); 637 fh->nexthdr = nexthdr; 638 fh->reserved = 0; 639 fh->frag_off = htons(IP6_MF); 640 frag_id = fh->identification; 641 642 first_len = skb_pagelen(skb); 643 skb->data_len = first_len - skb_headlen(skb); 644 skb->len = first_len; 645 skb->nh.ipv6h->payload_len = htons(first_len - sizeof(struct ipv6hdr)); 646 647 648 for (;;) { 649 /* Prepare header of the next frame, 650 * before previous one went down. */ 651 if (frag) { 652 frag->ip_summed = CHECKSUM_NONE; 653 frag->h.raw = frag->data; 654 fh = (struct frag_hdr*)__skb_push(frag, sizeof(struct frag_hdr)); 655 frag->nh.raw = __skb_push(frag, hlen); 656 memcpy(frag->nh.raw, tmp_hdr, hlen); 657 offset += skb->len - hlen - sizeof(struct frag_hdr); 658 fh->nexthdr = nexthdr; 659 fh->reserved = 0; 660 fh->frag_off = htons(offset); 661 if (frag->next != NULL) 662 fh->frag_off |= htons(IP6_MF); 663 fh->identification = frag_id; 664 frag->nh.ipv6h->payload_len = htons(frag->len - sizeof(struct ipv6hdr)); 665 ip6_copy_metadata(frag, skb); 666 } 667 668 err = output(skb); 669 if(!err) 670 IP6_INC_STATS(IPSTATS_MIB_FRAGCREATES); 671 672 if (err || !frag) 673 break; 674 675 skb = frag; 676 frag = skb->next; 677 skb->next = NULL; 678 } 679 680 kfree(tmp_hdr); 681 682 if (err == 0) { 683 IP6_INC_STATS(IPSTATS_MIB_FRAGOKS); 684 return 0; 685 } 686 687 while (frag) { 688 skb = frag->next; 689 kfree_skb(frag); 690 frag = skb; 691 } 692 693 IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS); 694 return err; 695 } 696 697 slow_path: 698 left = skb->len - hlen; /* Space per frame */ 699 ptr = hlen; /* Where to start from */ 700 701 /* 702 * Fragment the datagram. 703 */ 704 705 *prevhdr = NEXTHDR_FRAGMENT; 706 707 /* 708 * Keep copying data until we run out. 709 */ 710 while(left > 0) { 711 len = left; 712 /* IF: it doesn't fit, use 'mtu' - the data space left */ 713 if (len > mtu) 714 len = mtu; 715 /* IF: we are not sending upto and including the packet end 716 then align the next start on an eight byte boundary */ 717 if (len < left) { 718 len &= ~7; 719 } 720 /* 721 * Allocate buffer. 722 */ 723 724 if ((frag = alloc_skb(len+hlen+sizeof(struct frag_hdr)+LL_RESERVED_SPACE(rt->u.dst.dev), GFP_ATOMIC)) == NULL) { 725 NETDEBUG(KERN_INFO "IPv6: frag: no memory for new fragment!\n"); 726 IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS); 727 err = -ENOMEM; 728 goto fail; 729 } 730 731 /* 732 * Set up data on packet 733 */ 734 735 ip6_copy_metadata(frag, skb); 736 skb_reserve(frag, LL_RESERVED_SPACE(rt->u.dst.dev)); 737 skb_put(frag, len + hlen + sizeof(struct frag_hdr)); 738 frag->nh.raw = frag->data; 739 fh = (struct frag_hdr*)(frag->data + hlen); 740 frag->h.raw = frag->data + hlen + sizeof(struct frag_hdr); 741 742 /* 743 * Charge the memory for the fragment to any owner 744 * it might possess 745 */ 746 if (skb->sk) 747 skb_set_owner_w(frag, skb->sk); 748 749 /* 750 * Copy the packet header into the new buffer. 751 */ 752 memcpy(frag->nh.raw, skb->data, hlen); 753 754 /* 755 * Build fragment header. 756 */ 757 fh->nexthdr = nexthdr; 758 fh->reserved = 0; 759 if (!frag_id) { 760 ipv6_select_ident(skb, fh); 761 frag_id = fh->identification; 762 } else 763 fh->identification = frag_id; 764 765 /* 766 * Copy a block of the IP datagram. 767 */ 768 if (skb_copy_bits(skb, ptr, frag->h.raw, len)) 769 BUG(); 770 left -= len; 771 772 fh->frag_off = htons(offset); 773 if (left > 0) 774 fh->frag_off |= htons(IP6_MF); 775 frag->nh.ipv6h->payload_len = htons(frag->len - sizeof(struct ipv6hdr)); 776 777 ptr += len; 778 offset += len; 779 780 /* 781 * Put this fragment into the sending queue. 782 */ 783 err = output(frag); 784 if (err) 785 goto fail; 786 787 IP6_INC_STATS(IPSTATS_MIB_FRAGCREATES); 788 } 789 kfree_skb(skb); 790 IP6_INC_STATS(IPSTATS_MIB_FRAGOKS); 791 return err; 792 793 fail: 794 kfree_skb(skb); 795 IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS); 796 return err; 797 } 798 799 static inline int ip6_rt_check(struct rt6key *rt_key, 800 struct in6_addr *fl_addr, 801 struct in6_addr *addr_cache) 802 { 803 return ((rt_key->plen != 128 || !ipv6_addr_equal(fl_addr, &rt_key->addr)) && 804 (addr_cache == NULL || !ipv6_addr_equal(fl_addr, addr_cache))); 805 } 806 807 static struct dst_entry *ip6_sk_dst_check(struct sock *sk, 808 struct dst_entry *dst, 809 struct flowi *fl) 810 { 811 struct ipv6_pinfo *np = inet6_sk(sk); 812 struct rt6_info *rt = (struct rt6_info *)dst; 813 814 if (!dst) 815 goto out; 816 817 /* Yes, checking route validity in not connected 818 * case is not very simple. Take into account, 819 * that we do not support routing by source, TOS, 820 * and MSG_DONTROUTE --ANK (980726) 821 * 822 * 1. ip6_rt_check(): If route was host route, 823 * check that cached destination is current. 824 * If it is network route, we still may 825 * check its validity using saved pointer 826 * to the last used address: daddr_cache. 827 * We do not want to save whole address now, 828 * (because main consumer of this service 829 * is tcp, which has not this problem), 830 * so that the last trick works only on connected 831 * sockets. 832 * 2. oif also should be the same. 833 */ 834 if (ip6_rt_check(&rt->rt6i_dst, &fl->fl6_dst, np->daddr_cache) || 835 #ifdef CONFIG_IPV6_SUBTREES 836 ip6_rt_check(&rt->rt6i_src, &fl->fl6_src, np->saddr_cache) || 837 #endif 838 (fl->oif && fl->oif != dst->dev->ifindex)) { 839 dst_release(dst); 840 dst = NULL; 841 } 842 843 out: 844 return dst; 845 } 846 847 static int ip6_dst_lookup_tail(struct sock *sk, 848 struct dst_entry **dst, struct flowi *fl) 849 { 850 int err; 851 852 if (*dst == NULL) 853 *dst = ip6_route_output(sk, fl); 854 855 if ((err = (*dst)->error)) 856 goto out_err_release; 857 858 if (ipv6_addr_any(&fl->fl6_src)) { 859 err = ipv6_get_saddr(*dst, &fl->fl6_dst, &fl->fl6_src); 860 if (err) 861 goto out_err_release; 862 } 863 864 return 0; 865 866 out_err_release: 867 dst_release(*dst); 868 *dst = NULL; 869 return err; 870 } 871 872 /** 873 * ip6_dst_lookup - perform route lookup on flow 874 * @sk: socket which provides route info 875 * @dst: pointer to dst_entry * for result 876 * @fl: flow to lookup 877 * 878 * This function performs a route lookup on the given flow. 879 * 880 * It returns zero on success, or a standard errno code on error. 881 */ 882 int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl) 883 { 884 *dst = NULL; 885 return ip6_dst_lookup_tail(sk, dst, fl); 886 } 887 EXPORT_SYMBOL_GPL(ip6_dst_lookup); 888 889 /** 890 * ip6_sk_dst_lookup - perform socket cached route lookup on flow 891 * @sk: socket which provides the dst cache and route info 892 * @dst: pointer to dst_entry * for result 893 * @fl: flow to lookup 894 * 895 * This function performs a route lookup on the given flow with the 896 * possibility of using the cached route in the socket if it is valid. 897 * It will take the socket dst lock when operating on the dst cache. 898 * As a result, this function can only be used in process context. 899 * 900 * It returns zero on success, or a standard errno code on error. 901 */ 902 int ip6_sk_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl) 903 { 904 *dst = NULL; 905 if (sk) { 906 *dst = sk_dst_check(sk, inet6_sk(sk)->dst_cookie); 907 *dst = ip6_sk_dst_check(sk, *dst, fl); 908 } 909 910 return ip6_dst_lookup_tail(sk, dst, fl); 911 } 912 EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup); 913 914 static inline int ip6_ufo_append_data(struct sock *sk, 915 int getfrag(void *from, char *to, int offset, int len, 916 int odd, struct sk_buff *skb), 917 void *from, int length, int hh_len, int fragheaderlen, 918 int transhdrlen, int mtu,unsigned int flags) 919 920 { 921 struct sk_buff *skb; 922 int err; 923 924 /* There is support for UDP large send offload by network 925 * device, so create one single skb packet containing complete 926 * udp datagram 927 */ 928 if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) { 929 skb = sock_alloc_send_skb(sk, 930 hh_len + fragheaderlen + transhdrlen + 20, 931 (flags & MSG_DONTWAIT), &err); 932 if (skb == NULL) 933 return -ENOMEM; 934 935 /* reserve space for Hardware header */ 936 skb_reserve(skb, hh_len); 937 938 /* create space for UDP/IP header */ 939 skb_put(skb,fragheaderlen + transhdrlen); 940 941 /* initialize network header pointer */ 942 skb->nh.raw = skb->data; 943 944 /* initialize protocol header pointer */ 945 skb->h.raw = skb->data + fragheaderlen; 946 947 skb->ip_summed = CHECKSUM_PARTIAL; 948 skb->csum = 0; 949 sk->sk_sndmsg_off = 0; 950 } 951 952 err = skb_append_datato_frags(sk,skb, getfrag, from, 953 (length - transhdrlen)); 954 if (!err) { 955 struct frag_hdr fhdr; 956 957 /* specify the length of each IP datagram fragment*/ 958 skb_shinfo(skb)->gso_size = mtu - fragheaderlen - 959 sizeof(struct frag_hdr); 960 skb_shinfo(skb)->gso_type = SKB_GSO_UDP; 961 ipv6_select_ident(skb, &fhdr); 962 skb_shinfo(skb)->ip6_frag_id = fhdr.identification; 963 __skb_queue_tail(&sk->sk_write_queue, skb); 964 965 return 0; 966 } 967 /* There is not enough support do UPD LSO, 968 * so follow normal path 969 */ 970 kfree_skb(skb); 971 972 return err; 973 } 974 975 int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to, 976 int offset, int len, int odd, struct sk_buff *skb), 977 void *from, int length, int transhdrlen, 978 int hlimit, int tclass, struct ipv6_txoptions *opt, struct flowi *fl, 979 struct rt6_info *rt, unsigned int flags) 980 { 981 struct inet_sock *inet = inet_sk(sk); 982 struct ipv6_pinfo *np = inet6_sk(sk); 983 struct sk_buff *skb; 984 unsigned int maxfraglen, fragheaderlen; 985 int exthdrlen; 986 int hh_len; 987 int mtu; 988 int copy; 989 int err; 990 int offset = 0; 991 int csummode = CHECKSUM_NONE; 992 993 if (flags&MSG_PROBE) 994 return 0; 995 if (skb_queue_empty(&sk->sk_write_queue)) { 996 /* 997 * setup for corking 998 */ 999 if (opt) { 1000 if (np->cork.opt == NULL) { 1001 np->cork.opt = kmalloc(opt->tot_len, 1002 sk->sk_allocation); 1003 if (unlikely(np->cork.opt == NULL)) 1004 return -ENOBUFS; 1005 } else if (np->cork.opt->tot_len < opt->tot_len) { 1006 printk(KERN_DEBUG "ip6_append_data: invalid option length\n"); 1007 return -EINVAL; 1008 } 1009 memcpy(np->cork.opt, opt, opt->tot_len); 1010 inet->cork.flags |= IPCORK_OPT; 1011 /* need source address above miyazawa*/ 1012 } 1013 dst_hold(&rt->u.dst); 1014 np->cork.rt = rt; 1015 inet->cork.fl = *fl; 1016 np->cork.hop_limit = hlimit; 1017 np->cork.tclass = tclass; 1018 mtu = dst_mtu(rt->u.dst.path); 1019 if (np->frag_size < mtu) { 1020 if (np->frag_size) 1021 mtu = np->frag_size; 1022 } 1023 inet->cork.fragsize = mtu; 1024 if (dst_allfrag(rt->u.dst.path)) 1025 inet->cork.flags |= IPCORK_ALLFRAG; 1026 inet->cork.length = 0; 1027 sk->sk_sndmsg_page = NULL; 1028 sk->sk_sndmsg_off = 0; 1029 exthdrlen = rt->u.dst.header_len + (opt ? opt->opt_flen : 0); 1030 length += exthdrlen; 1031 transhdrlen += exthdrlen; 1032 } else { 1033 rt = np->cork.rt; 1034 fl = &inet->cork.fl; 1035 if (inet->cork.flags & IPCORK_OPT) 1036 opt = np->cork.opt; 1037 transhdrlen = 0; 1038 exthdrlen = 0; 1039 mtu = inet->cork.fragsize; 1040 } 1041 1042 hh_len = LL_RESERVED_SPACE(rt->u.dst.dev); 1043 1044 fragheaderlen = sizeof(struct ipv6hdr) + rt->u.dst.nfheader_len + (opt ? opt->opt_nflen : 0); 1045 maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr); 1046 1047 if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) { 1048 if (inet->cork.length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) { 1049 ipv6_local_error(sk, EMSGSIZE, fl, mtu-exthdrlen); 1050 return -EMSGSIZE; 1051 } 1052 } 1053 1054 /* 1055 * Let's try using as much space as possible. 1056 * Use MTU if total length of the message fits into the MTU. 1057 * Otherwise, we need to reserve fragment header and 1058 * fragment alignment (= 8-15 octects, in total). 1059 * 1060 * Note that we may need to "move" the data from the tail of 1061 * of the buffer to the new fragment when we split 1062 * the message. 1063 * 1064 * FIXME: It may be fragmented into multiple chunks 1065 * at once if non-fragmentable extension headers 1066 * are too large. 1067 * --yoshfuji 1068 */ 1069 1070 inet->cork.length += length; 1071 if (((length > mtu) && (sk->sk_protocol == IPPROTO_UDP)) && 1072 (rt->u.dst.dev->features & NETIF_F_UFO)) { 1073 1074 err = ip6_ufo_append_data(sk, getfrag, from, length, hh_len, 1075 fragheaderlen, transhdrlen, mtu, 1076 flags); 1077 if (err) 1078 goto error; 1079 return 0; 1080 } 1081 1082 if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) 1083 goto alloc_new_skb; 1084 1085 while (length > 0) { 1086 /* Check if the remaining data fits into current packet. */ 1087 copy = (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len; 1088 if (copy < length) 1089 copy = maxfraglen - skb->len; 1090 1091 if (copy <= 0) { 1092 char *data; 1093 unsigned int datalen; 1094 unsigned int fraglen; 1095 unsigned int fraggap; 1096 unsigned int alloclen; 1097 struct sk_buff *skb_prev; 1098 alloc_new_skb: 1099 skb_prev = skb; 1100 1101 /* There's no room in the current skb */ 1102 if (skb_prev) 1103 fraggap = skb_prev->len - maxfraglen; 1104 else 1105 fraggap = 0; 1106 1107 /* 1108 * If remaining data exceeds the mtu, 1109 * we know we need more fragment(s). 1110 */ 1111 datalen = length + fraggap; 1112 if (datalen > (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen) 1113 datalen = maxfraglen - fragheaderlen; 1114 1115 fraglen = datalen + fragheaderlen; 1116 if ((flags & MSG_MORE) && 1117 !(rt->u.dst.dev->features&NETIF_F_SG)) 1118 alloclen = mtu; 1119 else 1120 alloclen = datalen + fragheaderlen; 1121 1122 /* 1123 * The last fragment gets additional space at tail. 1124 * Note: we overallocate on fragments with MSG_MODE 1125 * because we have no idea if we're the last one. 1126 */ 1127 if (datalen == length + fraggap) 1128 alloclen += rt->u.dst.trailer_len; 1129 1130 /* 1131 * We just reserve space for fragment header. 1132 * Note: this may be overallocation if the message 1133 * (without MSG_MORE) fits into the MTU. 1134 */ 1135 alloclen += sizeof(struct frag_hdr); 1136 1137 if (transhdrlen) { 1138 skb = sock_alloc_send_skb(sk, 1139 alloclen + hh_len, 1140 (flags & MSG_DONTWAIT), &err); 1141 } else { 1142 skb = NULL; 1143 if (atomic_read(&sk->sk_wmem_alloc) <= 1144 2 * sk->sk_sndbuf) 1145 skb = sock_wmalloc(sk, 1146 alloclen + hh_len, 1, 1147 sk->sk_allocation); 1148 if (unlikely(skb == NULL)) 1149 err = -ENOBUFS; 1150 } 1151 if (skb == NULL) 1152 goto error; 1153 /* 1154 * Fill in the control structures 1155 */ 1156 skb->ip_summed = csummode; 1157 skb->csum = 0; 1158 /* reserve for fragmentation */ 1159 skb_reserve(skb, hh_len+sizeof(struct frag_hdr)); 1160 1161 /* 1162 * Find where to start putting bytes 1163 */ 1164 data = skb_put(skb, fraglen); 1165 skb->nh.raw = data + exthdrlen; 1166 data += fragheaderlen; 1167 skb->h.raw = data + exthdrlen; 1168 1169 if (fraggap) { 1170 skb->csum = skb_copy_and_csum_bits( 1171 skb_prev, maxfraglen, 1172 data + transhdrlen, fraggap, 0); 1173 skb_prev->csum = csum_sub(skb_prev->csum, 1174 skb->csum); 1175 data += fraggap; 1176 pskb_trim_unique(skb_prev, maxfraglen); 1177 } 1178 copy = datalen - transhdrlen - fraggap; 1179 if (copy < 0) { 1180 err = -EINVAL; 1181 kfree_skb(skb); 1182 goto error; 1183 } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) { 1184 err = -EFAULT; 1185 kfree_skb(skb); 1186 goto error; 1187 } 1188 1189 offset += copy; 1190 length -= datalen - fraggap; 1191 transhdrlen = 0; 1192 exthdrlen = 0; 1193 csummode = CHECKSUM_NONE; 1194 1195 /* 1196 * Put the packet on the pending queue 1197 */ 1198 __skb_queue_tail(&sk->sk_write_queue, skb); 1199 continue; 1200 } 1201 1202 if (copy > length) 1203 copy = length; 1204 1205 if (!(rt->u.dst.dev->features&NETIF_F_SG)) { 1206 unsigned int off; 1207 1208 off = skb->len; 1209 if (getfrag(from, skb_put(skb, copy), 1210 offset, copy, off, skb) < 0) { 1211 __skb_trim(skb, off); 1212 err = -EFAULT; 1213 goto error; 1214 } 1215 } else { 1216 int i = skb_shinfo(skb)->nr_frags; 1217 skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1]; 1218 struct page *page = sk->sk_sndmsg_page; 1219 int off = sk->sk_sndmsg_off; 1220 unsigned int left; 1221 1222 if (page && (left = PAGE_SIZE - off) > 0) { 1223 if (copy >= left) 1224 copy = left; 1225 if (page != frag->page) { 1226 if (i == MAX_SKB_FRAGS) { 1227 err = -EMSGSIZE; 1228 goto error; 1229 } 1230 get_page(page); 1231 skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0); 1232 frag = &skb_shinfo(skb)->frags[i]; 1233 } 1234 } else if(i < MAX_SKB_FRAGS) { 1235 if (copy > PAGE_SIZE) 1236 copy = PAGE_SIZE; 1237 page = alloc_pages(sk->sk_allocation, 0); 1238 if (page == NULL) { 1239 err = -ENOMEM; 1240 goto error; 1241 } 1242 sk->sk_sndmsg_page = page; 1243 sk->sk_sndmsg_off = 0; 1244 1245 skb_fill_page_desc(skb, i, page, 0, 0); 1246 frag = &skb_shinfo(skb)->frags[i]; 1247 skb->truesize += PAGE_SIZE; 1248 atomic_add(PAGE_SIZE, &sk->sk_wmem_alloc); 1249 } else { 1250 err = -EMSGSIZE; 1251 goto error; 1252 } 1253 if (getfrag(from, page_address(frag->page)+frag->page_offset+frag->size, offset, copy, skb->len, skb) < 0) { 1254 err = -EFAULT; 1255 goto error; 1256 } 1257 sk->sk_sndmsg_off += copy; 1258 frag->size += copy; 1259 skb->len += copy; 1260 skb->data_len += copy; 1261 } 1262 offset += copy; 1263 length -= copy; 1264 } 1265 return 0; 1266 error: 1267 inet->cork.length -= length; 1268 IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS); 1269 return err; 1270 } 1271 1272 int ip6_push_pending_frames(struct sock *sk) 1273 { 1274 struct sk_buff *skb, *tmp_skb; 1275 struct sk_buff **tail_skb; 1276 struct in6_addr final_dst_buf, *final_dst = &final_dst_buf; 1277 struct inet_sock *inet = inet_sk(sk); 1278 struct ipv6_pinfo *np = inet6_sk(sk); 1279 struct ipv6hdr *hdr; 1280 struct ipv6_txoptions *opt = np->cork.opt; 1281 struct rt6_info *rt = np->cork.rt; 1282 struct flowi *fl = &inet->cork.fl; 1283 unsigned char proto = fl->proto; 1284 int err = 0; 1285 1286 if ((skb = __skb_dequeue(&sk->sk_write_queue)) == NULL) 1287 goto out; 1288 tail_skb = &(skb_shinfo(skb)->frag_list); 1289 1290 /* move skb->data to ip header from ext header */ 1291 if (skb->data < skb->nh.raw) 1292 __skb_pull(skb, skb->nh.raw - skb->data); 1293 while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) { 1294 __skb_pull(tmp_skb, skb->h.raw - skb->nh.raw); 1295 *tail_skb = tmp_skb; 1296 tail_skb = &(tmp_skb->next); 1297 skb->len += tmp_skb->len; 1298 skb->data_len += tmp_skb->len; 1299 skb->truesize += tmp_skb->truesize; 1300 __sock_put(tmp_skb->sk); 1301 tmp_skb->destructor = NULL; 1302 tmp_skb->sk = NULL; 1303 } 1304 1305 ipv6_addr_copy(final_dst, &fl->fl6_dst); 1306 __skb_pull(skb, skb->h.raw - skb->nh.raw); 1307 if (opt && opt->opt_flen) 1308 ipv6_push_frag_opts(skb, opt, &proto); 1309 if (opt && opt->opt_nflen) 1310 ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst); 1311 1312 skb->nh.ipv6h = hdr = (struct ipv6hdr*) skb_push(skb, sizeof(struct ipv6hdr)); 1313 1314 *(u32*)hdr = fl->fl6_flowlabel | 1315 htonl(0x60000000 | ((int)np->cork.tclass << 20)); 1316 1317 if (skb->len <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) 1318 hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); 1319 else 1320 hdr->payload_len = 0; 1321 hdr->hop_limit = np->cork.hop_limit; 1322 hdr->nexthdr = proto; 1323 ipv6_addr_copy(&hdr->saddr, &fl->fl6_src); 1324 ipv6_addr_copy(&hdr->daddr, final_dst); 1325 1326 skb->priority = sk->sk_priority; 1327 1328 skb->dst = dst_clone(&rt->u.dst); 1329 IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS); 1330 err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, skb->dst->dev, dst_output); 1331 if (err) { 1332 if (err > 0) 1333 err = np->recverr ? net_xmit_errno(err) : 0; 1334 if (err) 1335 goto error; 1336 } 1337 1338 out: 1339 inet->cork.flags &= ~IPCORK_OPT; 1340 kfree(np->cork.opt); 1341 np->cork.opt = NULL; 1342 if (np->cork.rt) { 1343 dst_release(&np->cork.rt->u.dst); 1344 np->cork.rt = NULL; 1345 inet->cork.flags &= ~IPCORK_ALLFRAG; 1346 } 1347 memset(&inet->cork.fl, 0, sizeof(inet->cork.fl)); 1348 return err; 1349 error: 1350 goto out; 1351 } 1352 1353 void ip6_flush_pending_frames(struct sock *sk) 1354 { 1355 struct inet_sock *inet = inet_sk(sk); 1356 struct ipv6_pinfo *np = inet6_sk(sk); 1357 struct sk_buff *skb; 1358 1359 while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) { 1360 IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS); 1361 kfree_skb(skb); 1362 } 1363 1364 inet->cork.flags &= ~IPCORK_OPT; 1365 1366 kfree(np->cork.opt); 1367 np->cork.opt = NULL; 1368 if (np->cork.rt) { 1369 dst_release(&np->cork.rt->u.dst); 1370 np->cork.rt = NULL; 1371 inet->cork.flags &= ~IPCORK_ALLFRAG; 1372 } 1373 memset(&inet->cork.fl, 0, sizeof(inet->cork.fl)); 1374 } 1375