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 struct dst_entry *dst = skb->dst; 76 77 if (dst->hh) 78 return neigh_hh_output(dst->hh, skb); 79 else if (dst->neighbour) 80 return dst->neighbour->output(skb); 81 82 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES); 83 kfree_skb(skb); 84 return -EINVAL; 85 86 } 87 88 /* dev_loopback_xmit for use with netfilter. */ 89 static int ip6_dev_loopback_xmit(struct sk_buff *newskb) 90 { 91 newskb->mac.raw = newskb->data; 92 __skb_pull(newskb, newskb->nh.raw - newskb->data); 93 newskb->pkt_type = PACKET_LOOPBACK; 94 newskb->ip_summed = CHECKSUM_UNNECESSARY; 95 BUG_TRAP(newskb->dst); 96 97 netif_rx(newskb); 98 return 0; 99 } 100 101 102 static int ip6_output2(struct sk_buff *skb) 103 { 104 struct dst_entry *dst = skb->dst; 105 struct net_device *dev = dst->dev; 106 107 skb->protocol = htons(ETH_P_IPV6); 108 skb->dev = dev; 109 110 if (ipv6_addr_is_multicast(&skb->nh.ipv6h->daddr)) { 111 struct ipv6_pinfo* np = skb->sk ? inet6_sk(skb->sk) : NULL; 112 struct inet6_dev *idev = ip6_dst_idev(skb->dst); 113 114 if (!(dev->flags & IFF_LOOPBACK) && (!np || np->mc_loop) && 115 ipv6_chk_mcast_addr(dev, &skb->nh.ipv6h->daddr, 116 &skb->nh.ipv6h->saddr)) { 117 struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); 118 119 /* Do not check for IFF_ALLMULTI; multicast routing 120 is not supported in any case. 121 */ 122 if (newskb) 123 NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, newskb, NULL, 124 newskb->dev, 125 ip6_dev_loopback_xmit); 126 127 if (skb->nh.ipv6h->hop_limit == 0) { 128 IP6_INC_STATS(idev, IPSTATS_MIB_OUTDISCARDS); 129 kfree_skb(skb); 130 return 0; 131 } 132 } 133 134 IP6_INC_STATS(idev, IPSTATS_MIB_OUTMCASTPKTS); 135 } 136 137 return NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, skb,NULL, skb->dev,ip6_output_finish); 138 } 139 140 int ip6_output(struct sk_buff *skb) 141 { 142 if ((skb->len > dst_mtu(skb->dst) && !skb_is_gso(skb)) || 143 dst_allfrag(skb->dst)) 144 return ip6_fragment(skb, ip6_output2); 145 else 146 return ip6_output2(skb); 147 } 148 149 /* 150 * xmit an sk_buff (used by TCP) 151 */ 152 153 int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl, 154 struct ipv6_txoptions *opt, int ipfragok) 155 { 156 struct ipv6_pinfo *np = inet6_sk(sk); 157 struct in6_addr *first_hop = &fl->fl6_dst; 158 struct dst_entry *dst = skb->dst; 159 struct ipv6hdr *hdr; 160 u8 proto = fl->proto; 161 int seg_len = skb->len; 162 int hlimit, tclass; 163 u32 mtu; 164 165 if (opt) { 166 int head_room; 167 168 /* First: exthdrs may take lots of space (~8K for now) 169 MAX_HEADER is not enough. 170 */ 171 head_room = opt->opt_nflen + opt->opt_flen; 172 seg_len += head_room; 173 head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev); 174 175 if (skb_headroom(skb) < head_room) { 176 struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room); 177 if (skb2 == NULL) { 178 IP6_INC_STATS(ip6_dst_idev(skb->dst), 179 IPSTATS_MIB_OUTDISCARDS); 180 kfree_skb(skb); 181 return -ENOBUFS; 182 } 183 kfree_skb(skb); 184 skb = skb2; 185 if (sk) 186 skb_set_owner_w(skb, sk); 187 } 188 if (opt->opt_flen) 189 ipv6_push_frag_opts(skb, opt, &proto); 190 if (opt->opt_nflen) 191 ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop); 192 } 193 194 hdr = skb->nh.ipv6h = (struct ipv6hdr*)skb_push(skb, sizeof(struct ipv6hdr)); 195 196 /* 197 * Fill in the IPv6 header 198 */ 199 200 hlimit = -1; 201 if (np) 202 hlimit = np->hop_limit; 203 if (hlimit < 0) 204 hlimit = dst_metric(dst, RTAX_HOPLIMIT); 205 if (hlimit < 0) 206 hlimit = ipv6_get_hoplimit(dst->dev); 207 208 tclass = -1; 209 if (np) 210 tclass = np->tclass; 211 if (tclass < 0) 212 tclass = 0; 213 214 *(__be32 *)hdr = htonl(0x60000000 | (tclass << 20)) | fl->fl6_flowlabel; 215 216 hdr->payload_len = htons(seg_len); 217 hdr->nexthdr = proto; 218 hdr->hop_limit = hlimit; 219 220 ipv6_addr_copy(&hdr->saddr, &fl->fl6_src); 221 ipv6_addr_copy(&hdr->daddr, first_hop); 222 223 skb->priority = sk->sk_priority; 224 225 mtu = dst_mtu(dst); 226 if ((skb->len <= mtu) || ipfragok || skb_is_gso(skb)) { 227 IP6_INC_STATS(ip6_dst_idev(skb->dst), 228 IPSTATS_MIB_OUTREQUESTS); 229 return NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, 230 dst_output); 231 } 232 233 if (net_ratelimit()) 234 printk(KERN_DEBUG "IPv6: sending pkt_too_big to self\n"); 235 skb->dev = dst->dev; 236 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev); 237 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS); 238 kfree_skb(skb); 239 return -EMSGSIZE; 240 } 241 242 /* 243 * To avoid extra problems ND packets are send through this 244 * routine. It's code duplication but I really want to avoid 245 * extra checks since ipv6_build_header is used by TCP (which 246 * is for us performance critical) 247 */ 248 249 int ip6_nd_hdr(struct sock *sk, struct sk_buff *skb, struct net_device *dev, 250 struct in6_addr *saddr, struct in6_addr *daddr, 251 int proto, int len) 252 { 253 struct ipv6_pinfo *np = inet6_sk(sk); 254 struct ipv6hdr *hdr; 255 int totlen; 256 257 skb->protocol = htons(ETH_P_IPV6); 258 skb->dev = dev; 259 260 totlen = len + sizeof(struct ipv6hdr); 261 262 hdr = (struct ipv6hdr *) skb_put(skb, sizeof(struct ipv6hdr)); 263 skb->nh.ipv6h = hdr; 264 265 *(__be32*)hdr = htonl(0x60000000); 266 267 hdr->payload_len = htons(len); 268 hdr->nexthdr = proto; 269 hdr->hop_limit = np->hop_limit; 270 271 ipv6_addr_copy(&hdr->saddr, saddr); 272 ipv6_addr_copy(&hdr->daddr, daddr); 273 274 return 0; 275 } 276 277 static int ip6_call_ra_chain(struct sk_buff *skb, int sel) 278 { 279 struct ip6_ra_chain *ra; 280 struct sock *last = NULL; 281 282 read_lock(&ip6_ra_lock); 283 for (ra = ip6_ra_chain; ra; ra = ra->next) { 284 struct sock *sk = ra->sk; 285 if (sk && ra->sel == sel && 286 (!sk->sk_bound_dev_if || 287 sk->sk_bound_dev_if == skb->dev->ifindex)) { 288 if (last) { 289 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); 290 if (skb2) 291 rawv6_rcv(last, skb2); 292 } 293 last = sk; 294 } 295 } 296 297 if (last) { 298 rawv6_rcv(last, skb); 299 read_unlock(&ip6_ra_lock); 300 return 1; 301 } 302 read_unlock(&ip6_ra_lock); 303 return 0; 304 } 305 306 static int ip6_forward_proxy_check(struct sk_buff *skb) 307 { 308 struct ipv6hdr *hdr = skb->nh.ipv6h; 309 u8 nexthdr = hdr->nexthdr; 310 int offset; 311 312 if (ipv6_ext_hdr(nexthdr)) { 313 offset = ipv6_skip_exthdr(skb, sizeof(*hdr), &nexthdr); 314 if (offset < 0) 315 return 0; 316 } else 317 offset = sizeof(struct ipv6hdr); 318 319 if (nexthdr == IPPROTO_ICMPV6) { 320 struct icmp6hdr *icmp6; 321 322 if (!pskb_may_pull(skb, skb->nh.raw + offset + 1 - skb->data)) 323 return 0; 324 325 icmp6 = (struct icmp6hdr *)(skb->nh.raw + offset); 326 327 switch (icmp6->icmp6_type) { 328 case NDISC_ROUTER_SOLICITATION: 329 case NDISC_ROUTER_ADVERTISEMENT: 330 case NDISC_NEIGHBOUR_SOLICITATION: 331 case NDISC_NEIGHBOUR_ADVERTISEMENT: 332 case NDISC_REDIRECT: 333 /* For reaction involving unicast neighbor discovery 334 * message destined to the proxied address, pass it to 335 * input function. 336 */ 337 return 1; 338 default: 339 break; 340 } 341 } 342 343 /* 344 * The proxying router can't forward traffic sent to a link-local 345 * address, so signal the sender and discard the packet. This 346 * behavior is clarified by the MIPv6 specification. 347 */ 348 if (ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) { 349 dst_link_failure(skb); 350 return -1; 351 } 352 353 return 0; 354 } 355 356 static inline int ip6_forward_finish(struct sk_buff *skb) 357 { 358 return dst_output(skb); 359 } 360 361 int ip6_forward(struct sk_buff *skb) 362 { 363 struct dst_entry *dst = skb->dst; 364 struct ipv6hdr *hdr = skb->nh.ipv6h; 365 struct inet6_skb_parm *opt = IP6CB(skb); 366 367 if (ipv6_devconf.forwarding == 0) 368 goto error; 369 370 if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) { 371 IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS); 372 goto drop; 373 } 374 375 skb->ip_summed = CHECKSUM_NONE; 376 377 /* 378 * We DO NOT make any processing on 379 * RA packets, pushing them to user level AS IS 380 * without ane WARRANTY that application will be able 381 * to interpret them. The reason is that we 382 * cannot make anything clever here. 383 * 384 * We are not end-node, so that if packet contains 385 * AH/ESP, we cannot make anything. 386 * Defragmentation also would be mistake, RA packets 387 * cannot be fragmented, because there is no warranty 388 * that different fragments will go along one path. --ANK 389 */ 390 if (opt->ra) { 391 u8 *ptr = skb->nh.raw + opt->ra; 392 if (ip6_call_ra_chain(skb, (ptr[2]<<8) + ptr[3])) 393 return 0; 394 } 395 396 /* 397 * check and decrement ttl 398 */ 399 if (hdr->hop_limit <= 1) { 400 /* Force OUTPUT device used as source address */ 401 skb->dev = dst->dev; 402 icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, 403 0, skb->dev); 404 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS); 405 406 kfree_skb(skb); 407 return -ETIMEDOUT; 408 } 409 410 /* XXX: idev->cnf.proxy_ndp? */ 411 if (ipv6_devconf.proxy_ndp && 412 pneigh_lookup(&nd_tbl, &hdr->daddr, skb->dev, 0)) { 413 int proxied = ip6_forward_proxy_check(skb); 414 if (proxied > 0) 415 return ip6_input(skb); 416 else if (proxied < 0) { 417 IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS); 418 goto drop; 419 } 420 } 421 422 if (!xfrm6_route_forward(skb)) { 423 IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS); 424 goto drop; 425 } 426 dst = skb->dst; 427 428 /* IPv6 specs say nothing about it, but it is clear that we cannot 429 send redirects to source routed frames. 430 */ 431 if (skb->dev == dst->dev && dst->neighbour && opt->srcrt == 0) { 432 struct in6_addr *target = NULL; 433 struct rt6_info *rt; 434 struct neighbour *n = dst->neighbour; 435 436 /* 437 * incoming and outgoing devices are the same 438 * send a redirect. 439 */ 440 441 rt = (struct rt6_info *) dst; 442 if ((rt->rt6i_flags & RTF_GATEWAY)) 443 target = (struct in6_addr*)&n->primary_key; 444 else 445 target = &hdr->daddr; 446 447 /* Limit redirects both by destination (here) 448 and by source (inside ndisc_send_redirect) 449 */ 450 if (xrlim_allow(dst, 1*HZ)) 451 ndisc_send_redirect(skb, n, target); 452 } else if (ipv6_addr_type(&hdr->saddr)&(IPV6_ADDR_MULTICAST|IPV6_ADDR_LOOPBACK 453 |IPV6_ADDR_LINKLOCAL)) { 454 /* This check is security critical. */ 455 goto error; 456 } 457 458 if (skb->len > dst_mtu(dst)) { 459 /* Again, force OUTPUT device used as source address */ 460 skb->dev = dst->dev; 461 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, dst_mtu(dst), skb->dev); 462 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INTOOBIGERRORS); 463 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_FRAGFAILS); 464 kfree_skb(skb); 465 return -EMSGSIZE; 466 } 467 468 if (skb_cow(skb, dst->dev->hard_header_len)) { 469 IP6_INC_STATS(ip6_dst_idev(dst), IPSTATS_MIB_OUTDISCARDS); 470 goto drop; 471 } 472 473 hdr = skb->nh.ipv6h; 474 475 /* Mangling hops number delayed to point after skb COW */ 476 477 hdr->hop_limit--; 478 479 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS); 480 return NF_HOOK(PF_INET6,NF_IP6_FORWARD, skb, skb->dev, dst->dev, ip6_forward_finish); 481 482 error: 483 IP6_INC_STATS_BH(ip6_dst_idev(dst), IPSTATS_MIB_INADDRERRORS); 484 drop: 485 kfree_skb(skb); 486 return -EINVAL; 487 } 488 489 static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from) 490 { 491 to->pkt_type = from->pkt_type; 492 to->priority = from->priority; 493 to->protocol = from->protocol; 494 dst_release(to->dst); 495 to->dst = dst_clone(from->dst); 496 to->dev = from->dev; 497 to->mark = from->mark; 498 499 #ifdef CONFIG_NET_SCHED 500 to->tc_index = from->tc_index; 501 #endif 502 #ifdef CONFIG_NETFILTER 503 /* Connection association is same as pre-frag packet */ 504 nf_conntrack_put(to->nfct); 505 to->nfct = from->nfct; 506 nf_conntrack_get(to->nfct); 507 to->nfctinfo = from->nfctinfo; 508 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) 509 nf_conntrack_put_reasm(to->nfct_reasm); 510 to->nfct_reasm = from->nfct_reasm; 511 nf_conntrack_get_reasm(to->nfct_reasm); 512 #endif 513 #ifdef CONFIG_BRIDGE_NETFILTER 514 nf_bridge_put(to->nf_bridge); 515 to->nf_bridge = from->nf_bridge; 516 nf_bridge_get(to->nf_bridge); 517 #endif 518 #endif 519 skb_copy_secmark(to, from); 520 } 521 522 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) 523 { 524 u16 offset = sizeof(struct ipv6hdr); 525 struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr*)(skb->nh.ipv6h + 1); 526 unsigned int packet_len = skb->tail - skb->nh.raw; 527 int found_rhdr = 0; 528 *nexthdr = &skb->nh.ipv6h->nexthdr; 529 530 while (offset + 1 <= packet_len) { 531 532 switch (**nexthdr) { 533 534 case NEXTHDR_HOP: 535 break; 536 case NEXTHDR_ROUTING: 537 found_rhdr = 1; 538 break; 539 case NEXTHDR_DEST: 540 #ifdef CONFIG_IPV6_MIP6 541 if (ipv6_find_tlv(skb, offset, IPV6_TLV_HAO) >= 0) 542 break; 543 #endif 544 if (found_rhdr) 545 return offset; 546 break; 547 default : 548 return offset; 549 } 550 551 offset += ipv6_optlen(exthdr); 552 *nexthdr = &exthdr->nexthdr; 553 exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset); 554 } 555 556 return offset; 557 } 558 EXPORT_SYMBOL_GPL(ip6_find_1stfragopt); 559 560 static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)) 561 { 562 struct net_device *dev; 563 struct sk_buff *frag; 564 struct rt6_info *rt = (struct rt6_info*)skb->dst; 565 struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL; 566 struct ipv6hdr *tmp_hdr; 567 struct frag_hdr *fh; 568 unsigned int mtu, hlen, left, len; 569 __be32 frag_id = 0; 570 int ptr, offset = 0, err=0; 571 u8 *prevhdr, nexthdr = 0; 572 573 dev = rt->u.dst.dev; 574 hlen = ip6_find_1stfragopt(skb, &prevhdr); 575 nexthdr = *prevhdr; 576 577 mtu = dst_mtu(&rt->u.dst); 578 if (np && np->frag_size < mtu) { 579 if (np->frag_size) 580 mtu = np->frag_size; 581 } 582 mtu -= hlen + sizeof(struct frag_hdr); 583 584 if (skb_shinfo(skb)->frag_list) { 585 int first_len = skb_pagelen(skb); 586 587 if (first_len - hlen > mtu || 588 ((first_len - hlen) & 7) || 589 skb_cloned(skb)) 590 goto slow_path; 591 592 for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next) { 593 /* Correct geometry. */ 594 if (frag->len > mtu || 595 ((frag->len & 7) && frag->next) || 596 skb_headroom(frag) < hlen) 597 goto slow_path; 598 599 /* Partially cloned skb? */ 600 if (skb_shared(frag)) 601 goto slow_path; 602 603 BUG_ON(frag->sk); 604 if (skb->sk) { 605 sock_hold(skb->sk); 606 frag->sk = skb->sk; 607 frag->destructor = sock_wfree; 608 skb->truesize -= frag->truesize; 609 } 610 } 611 612 err = 0; 613 offset = 0; 614 frag = skb_shinfo(skb)->frag_list; 615 skb_shinfo(skb)->frag_list = NULL; 616 /* BUILD HEADER */ 617 618 *prevhdr = NEXTHDR_FRAGMENT; 619 tmp_hdr = kmemdup(skb->nh.raw, hlen, GFP_ATOMIC); 620 if (!tmp_hdr) { 621 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS); 622 return -ENOMEM; 623 } 624 625 __skb_pull(skb, hlen); 626 fh = (struct frag_hdr*)__skb_push(skb, sizeof(struct frag_hdr)); 627 skb->nh.raw = __skb_push(skb, hlen); 628 memcpy(skb->nh.raw, tmp_hdr, hlen); 629 630 ipv6_select_ident(skb, fh); 631 fh->nexthdr = nexthdr; 632 fh->reserved = 0; 633 fh->frag_off = htons(IP6_MF); 634 frag_id = fh->identification; 635 636 first_len = skb_pagelen(skb); 637 skb->data_len = first_len - skb_headlen(skb); 638 skb->len = first_len; 639 skb->nh.ipv6h->payload_len = htons(first_len - sizeof(struct ipv6hdr)); 640 641 dst_hold(&rt->u.dst); 642 643 for (;;) { 644 /* Prepare header of the next frame, 645 * before previous one went down. */ 646 if (frag) { 647 frag->ip_summed = CHECKSUM_NONE; 648 frag->h.raw = frag->data; 649 fh = (struct frag_hdr*)__skb_push(frag, sizeof(struct frag_hdr)); 650 frag->nh.raw = __skb_push(frag, hlen); 651 memcpy(frag->nh.raw, tmp_hdr, hlen); 652 offset += skb->len - hlen - sizeof(struct frag_hdr); 653 fh->nexthdr = nexthdr; 654 fh->reserved = 0; 655 fh->frag_off = htons(offset); 656 if (frag->next != NULL) 657 fh->frag_off |= htons(IP6_MF); 658 fh->identification = frag_id; 659 frag->nh.ipv6h->payload_len = htons(frag->len - sizeof(struct ipv6hdr)); 660 ip6_copy_metadata(frag, skb); 661 } 662 663 err = output(skb); 664 if(!err) 665 IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGCREATES); 666 667 if (err || !frag) 668 break; 669 670 skb = frag; 671 frag = skb->next; 672 skb->next = NULL; 673 } 674 675 kfree(tmp_hdr); 676 677 if (err == 0) { 678 IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGOKS); 679 dst_release(&rt->u.dst); 680 return 0; 681 } 682 683 while (frag) { 684 skb = frag->next; 685 kfree_skb(frag); 686 frag = skb; 687 } 688 689 IP6_INC_STATS(ip6_dst_idev(&rt->u.dst), IPSTATS_MIB_FRAGFAILS); 690 dst_release(&rt->u.dst); 691 return err; 692 } 693 694 slow_path: 695 left = skb->len - hlen; /* Space per frame */ 696 ptr = hlen; /* Where to start from */ 697 698 /* 699 * Fragment the datagram. 700 */ 701 702 *prevhdr = NEXTHDR_FRAGMENT; 703 704 /* 705 * Keep copying data until we run out. 706 */ 707 while(left > 0) { 708 len = left; 709 /* IF: it doesn't fit, use 'mtu' - the data space left */ 710 if (len > mtu) 711 len = mtu; 712 /* IF: we are not sending upto and including the packet end 713 then align the next start on an eight byte boundary */ 714 if (len < left) { 715 len &= ~7; 716 } 717 /* 718 * Allocate buffer. 719 */ 720 721 if ((frag = alloc_skb(len+hlen+sizeof(struct frag_hdr)+LL_RESERVED_SPACE(rt->u.dst.dev), GFP_ATOMIC)) == NULL) { 722 NETDEBUG(KERN_INFO "IPv6: frag: no memory for new fragment!\n"); 723 IP6_INC_STATS(ip6_dst_idev(skb->dst), 724 IPSTATS_MIB_FRAGFAILS); 725 err = -ENOMEM; 726 goto fail; 727 } 728 729 /* 730 * Set up data on packet 731 */ 732 733 ip6_copy_metadata(frag, skb); 734 skb_reserve(frag, LL_RESERVED_SPACE(rt->u.dst.dev)); 735 skb_put(frag, len + hlen + sizeof(struct frag_hdr)); 736 frag->nh.raw = frag->data; 737 fh = (struct frag_hdr*)(frag->data + hlen); 738 frag->h.raw = frag->data + hlen + sizeof(struct frag_hdr); 739 740 /* 741 * Charge the memory for the fragment to any owner 742 * it might possess 743 */ 744 if (skb->sk) 745 skb_set_owner_w(frag, skb->sk); 746 747 /* 748 * Copy the packet header into the new buffer. 749 */ 750 memcpy(frag->nh.raw, skb->data, hlen); 751 752 /* 753 * Build fragment header. 754 */ 755 fh->nexthdr = nexthdr; 756 fh->reserved = 0; 757 if (!frag_id) { 758 ipv6_select_ident(skb, fh); 759 frag_id = fh->identification; 760 } else 761 fh->identification = frag_id; 762 763 /* 764 * Copy a block of the IP datagram. 765 */ 766 if (skb_copy_bits(skb, ptr, frag->h.raw, len)) 767 BUG(); 768 left -= len; 769 770 fh->frag_off = htons(offset); 771 if (left > 0) 772 fh->frag_off |= htons(IP6_MF); 773 frag->nh.ipv6h->payload_len = htons(frag->len - sizeof(struct ipv6hdr)); 774 775 ptr += len; 776 offset += len; 777 778 /* 779 * Put this fragment into the sending queue. 780 */ 781 err = output(frag); 782 if (err) 783 goto fail; 784 785 IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGCREATES); 786 } 787 IP6_INC_STATS(ip6_dst_idev(skb->dst), 788 IPSTATS_MIB_FRAGOKS); 789 kfree_skb(skb); 790 return err; 791 792 fail: 793 IP6_INC_STATS(ip6_dst_idev(skb->dst), 794 IPSTATS_MIB_FRAGFAILS); 795 kfree_skb(skb); 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(rt->rt6i_idev, 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 *(__be32*)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(rt->rt6i_idev, 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(ip6_dst_idev(skb->dst), 1361 IPSTATS_MIB_OUTDISCARDS); 1362 kfree_skb(skb); 1363 } 1364 1365 inet->cork.flags &= ~IPCORK_OPT; 1366 1367 kfree(np->cork.opt); 1368 np->cork.opt = NULL; 1369 if (np->cork.rt) { 1370 dst_release(&np->cork.rt->u.dst); 1371 np->cork.rt = NULL; 1372 inet->cork.flags &= ~IPCORK_ALLFRAG; 1373 } 1374 memset(&inet->cork.fl, 0, sizeof(inet->cork.fl)); 1375 } 1376