Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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/config.h> |
| 32 | #include <linux/errno.h> |
| 33 | #include <linux/types.h> |
| 34 | #include <linux/string.h> |
| 35 | #include <linux/socket.h> |
| 36 | #include <linux/net.h> |
| 37 | #include <linux/netdevice.h> |
| 38 | #include <linux/if_arp.h> |
| 39 | #include <linux/in6.h> |
| 40 | #include <linux/tcp.h> |
| 41 | #include <linux/route.h> |
Herbert Xu | b59f45d | 2006-05-27 23:05:54 -0700 | [diff] [blame] | 42 | #include <linux/module.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | |
| 44 | #include <linux/netfilter.h> |
| 45 | #include <linux/netfilter_ipv6.h> |
| 46 | |
| 47 | #include <net/sock.h> |
| 48 | #include <net/snmp.h> |
| 49 | |
| 50 | #include <net/ipv6.h> |
| 51 | #include <net/ndisc.h> |
| 52 | #include <net/protocol.h> |
| 53 | #include <net/ip6_route.h> |
| 54 | #include <net/addrconf.h> |
| 55 | #include <net/rawv6.h> |
| 56 | #include <net/icmp.h> |
| 57 | #include <net/xfrm.h> |
| 58 | #include <net/checksum.h> |
| 59 | |
| 60 | static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)); |
| 61 | |
| 62 | static __inline__ void ipv6_select_ident(struct sk_buff *skb, struct frag_hdr *fhdr) |
| 63 | { |
| 64 | static u32 ipv6_fragmentation_id = 1; |
| 65 | static DEFINE_SPINLOCK(ip6_id_lock); |
| 66 | |
| 67 | spin_lock_bh(&ip6_id_lock); |
| 68 | fhdr->identification = htonl(ipv6_fragmentation_id); |
| 69 | if (++ipv6_fragmentation_id == 0) |
| 70 | ipv6_fragmentation_id = 1; |
| 71 | spin_unlock_bh(&ip6_id_lock); |
| 72 | } |
| 73 | |
| 74 | static inline int ip6_output_finish(struct sk_buff *skb) |
| 75 | { |
| 76 | |
| 77 | struct dst_entry *dst = skb->dst; |
| 78 | struct hh_cache *hh = dst->hh; |
| 79 | |
| 80 | if (hh) { |
| 81 | int hh_alen; |
| 82 | |
| 83 | read_lock_bh(&hh->hh_lock); |
| 84 | hh_alen = HH_DATA_ALIGN(hh->hh_len); |
| 85 | memcpy(skb->data - hh_alen, hh->hh_data, hh_alen); |
| 86 | read_unlock_bh(&hh->hh_lock); |
| 87 | skb_push(skb, hh->hh_len); |
| 88 | return hh->hh_output(skb); |
| 89 | } else if (dst->neighbour) |
| 90 | return dst->neighbour->output(skb); |
| 91 | |
| 92 | IP6_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES); |
| 93 | kfree_skb(skb); |
| 94 | return -EINVAL; |
| 95 | |
| 96 | } |
| 97 | |
| 98 | /* dev_loopback_xmit for use with netfilter. */ |
| 99 | static int ip6_dev_loopback_xmit(struct sk_buff *newskb) |
| 100 | { |
| 101 | newskb->mac.raw = newskb->data; |
| 102 | __skb_pull(newskb, newskb->nh.raw - newskb->data); |
| 103 | newskb->pkt_type = PACKET_LOOPBACK; |
| 104 | newskb->ip_summed = CHECKSUM_UNNECESSARY; |
| 105 | BUG_TRAP(newskb->dst); |
| 106 | |
| 107 | netif_rx(newskb); |
| 108 | return 0; |
| 109 | } |
| 110 | |
| 111 | |
| 112 | static int ip6_output2(struct sk_buff *skb) |
| 113 | { |
| 114 | struct dst_entry *dst = skb->dst; |
| 115 | struct net_device *dev = dst->dev; |
| 116 | |
| 117 | skb->protocol = htons(ETH_P_IPV6); |
| 118 | skb->dev = dev; |
| 119 | |
| 120 | if (ipv6_addr_is_multicast(&skb->nh.ipv6h->daddr)) { |
| 121 | struct ipv6_pinfo* np = skb->sk ? inet6_sk(skb->sk) : NULL; |
| 122 | |
| 123 | if (!(dev->flags & IFF_LOOPBACK) && (!np || np->mc_loop) && |
| 124 | ipv6_chk_mcast_addr(dev, &skb->nh.ipv6h->daddr, |
| 125 | &skb->nh.ipv6h->saddr)) { |
| 126 | struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); |
| 127 | |
| 128 | /* Do not check for IFF_ALLMULTI; multicast routing |
| 129 | is not supported in any case. |
| 130 | */ |
| 131 | if (newskb) |
| 132 | NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, newskb, NULL, |
| 133 | newskb->dev, |
| 134 | ip6_dev_loopback_xmit); |
| 135 | |
| 136 | if (skb->nh.ipv6h->hop_limit == 0) { |
| 137 | IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS); |
| 138 | kfree_skb(skb); |
| 139 | return 0; |
| 140 | } |
| 141 | } |
| 142 | |
| 143 | IP6_INC_STATS(IPSTATS_MIB_OUTMCASTPKTS); |
| 144 | } |
| 145 | |
| 146 | return NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, skb,NULL, skb->dev,ip6_output_finish); |
| 147 | } |
| 148 | |
| 149 | int ip6_output(struct sk_buff *skb) |
| 150 | { |
Herbert Xu | 7967168 | 2006-06-22 02:40:14 -0700 | [diff] [blame] | 151 | if ((skb->len > dst_mtu(skb->dst) && !skb_shinfo(skb)->gso_size) || |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 152 | dst_allfrag(skb->dst)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 153 | return ip6_fragment(skb, ip6_output2); |
| 154 | else |
| 155 | return ip6_output2(skb); |
| 156 | } |
| 157 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | /* |
| 159 | * xmit an sk_buff (used by TCP) |
| 160 | */ |
| 161 | |
| 162 | int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl, |
| 163 | struct ipv6_txoptions *opt, int ipfragok) |
| 164 | { |
Patrick McHardy | b30bd28 | 2006-03-23 01:17:25 -0800 | [diff] [blame] | 165 | struct ipv6_pinfo *np = inet6_sk(sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 166 | struct in6_addr *first_hop = &fl->fl6_dst; |
| 167 | struct dst_entry *dst = skb->dst; |
| 168 | struct ipv6hdr *hdr; |
| 169 | u8 proto = fl->proto; |
| 170 | int seg_len = skb->len; |
YOSHIFUJI Hideaki | 41a1f8e | 2005-09-08 10:19:03 +0900 | [diff] [blame] | 171 | int hlimit, tclass; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 172 | u32 mtu; |
| 173 | |
| 174 | if (opt) { |
| 175 | int head_room; |
| 176 | |
| 177 | /* First: exthdrs may take lots of space (~8K for now) |
| 178 | MAX_HEADER is not enough. |
| 179 | */ |
| 180 | head_room = opt->opt_nflen + opt->opt_flen; |
| 181 | seg_len += head_room; |
| 182 | head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev); |
| 183 | |
| 184 | if (skb_headroom(skb) < head_room) { |
| 185 | struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room); |
| 186 | kfree_skb(skb); |
| 187 | skb = skb2; |
| 188 | if (skb == NULL) { |
| 189 | IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS); |
| 190 | return -ENOBUFS; |
| 191 | } |
| 192 | if (sk) |
| 193 | skb_set_owner_w(skb, sk); |
| 194 | } |
| 195 | if (opt->opt_flen) |
| 196 | ipv6_push_frag_opts(skb, opt, &proto); |
| 197 | if (opt->opt_nflen) |
| 198 | ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop); |
| 199 | } |
| 200 | |
| 201 | hdr = skb->nh.ipv6h = (struct ipv6hdr*)skb_push(skb, sizeof(struct ipv6hdr)); |
| 202 | |
| 203 | /* |
| 204 | * Fill in the IPv6 header |
| 205 | */ |
| 206 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 207 | hlimit = -1; |
| 208 | if (np) |
| 209 | hlimit = np->hop_limit; |
| 210 | if (hlimit < 0) |
| 211 | hlimit = dst_metric(dst, RTAX_HOPLIMIT); |
| 212 | if (hlimit < 0) |
| 213 | hlimit = ipv6_get_hoplimit(dst->dev); |
| 214 | |
YOSHIFUJI Hideaki | 41a1f8e | 2005-09-08 10:19:03 +0900 | [diff] [blame] | 215 | tclass = -1; |
| 216 | if (np) |
| 217 | tclass = np->tclass; |
| 218 | if (tclass < 0) |
| 219 | tclass = 0; |
| 220 | |
| 221 | *(u32 *)hdr = htonl(0x60000000 | (tclass << 20)) | fl->fl6_flowlabel; |
| 222 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 223 | hdr->payload_len = htons(seg_len); |
| 224 | hdr->nexthdr = proto; |
| 225 | hdr->hop_limit = hlimit; |
| 226 | |
| 227 | ipv6_addr_copy(&hdr->saddr, &fl->fl6_src); |
| 228 | ipv6_addr_copy(&hdr->daddr, first_hop); |
| 229 | |
Patrick McHardy | a2c2064 | 2006-01-08 22:37:26 -0800 | [diff] [blame] | 230 | skb->priority = sk->sk_priority; |
| 231 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 232 | mtu = dst_mtu(dst); |
| 233 | if ((skb->len <= mtu) || ipfragok) { |
| 234 | IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS); |
Harald Welte | 6869c4d | 2005-08-09 19:24:19 -0700 | [diff] [blame] | 235 | return NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev, |
| 236 | dst_output); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 237 | } |
| 238 | |
| 239 | if (net_ratelimit()) |
| 240 | printk(KERN_DEBUG "IPv6: sending pkt_too_big to self\n"); |
| 241 | skb->dev = dst->dev; |
| 242 | icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev); |
| 243 | IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS); |
| 244 | kfree_skb(skb); |
| 245 | return -EMSGSIZE; |
| 246 | } |
| 247 | |
| 248 | /* |
| 249 | * To avoid extra problems ND packets are send through this |
| 250 | * routine. It's code duplication but I really want to avoid |
| 251 | * extra checks since ipv6_build_header is used by TCP (which |
| 252 | * is for us performance critical) |
| 253 | */ |
| 254 | |
| 255 | int ip6_nd_hdr(struct sock *sk, struct sk_buff *skb, struct net_device *dev, |
| 256 | struct in6_addr *saddr, struct in6_addr *daddr, |
| 257 | int proto, int len) |
| 258 | { |
| 259 | struct ipv6_pinfo *np = inet6_sk(sk); |
| 260 | struct ipv6hdr *hdr; |
| 261 | int totlen; |
| 262 | |
| 263 | skb->protocol = htons(ETH_P_IPV6); |
| 264 | skb->dev = dev; |
| 265 | |
| 266 | totlen = len + sizeof(struct ipv6hdr); |
| 267 | |
| 268 | hdr = (struct ipv6hdr *) skb_put(skb, sizeof(struct ipv6hdr)); |
| 269 | skb->nh.ipv6h = hdr; |
| 270 | |
| 271 | *(u32*)hdr = htonl(0x60000000); |
| 272 | |
| 273 | hdr->payload_len = htons(len); |
| 274 | hdr->nexthdr = proto; |
| 275 | hdr->hop_limit = np->hop_limit; |
| 276 | |
| 277 | ipv6_addr_copy(&hdr->saddr, saddr); |
| 278 | ipv6_addr_copy(&hdr->daddr, daddr); |
| 279 | |
| 280 | return 0; |
| 281 | } |
| 282 | |
| 283 | static int ip6_call_ra_chain(struct sk_buff *skb, int sel) |
| 284 | { |
| 285 | struct ip6_ra_chain *ra; |
| 286 | struct sock *last = NULL; |
| 287 | |
| 288 | read_lock(&ip6_ra_lock); |
| 289 | for (ra = ip6_ra_chain; ra; ra = ra->next) { |
| 290 | struct sock *sk = ra->sk; |
Andrew McDonald | 0bd1b59 | 2005-08-09 19:44:42 -0700 | [diff] [blame] | 291 | if (sk && ra->sel == sel && |
| 292 | (!sk->sk_bound_dev_if || |
| 293 | sk->sk_bound_dev_if == skb->dev->ifindex)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 294 | if (last) { |
| 295 | struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); |
| 296 | if (skb2) |
| 297 | rawv6_rcv(last, skb2); |
| 298 | } |
| 299 | last = sk; |
| 300 | } |
| 301 | } |
| 302 | |
| 303 | if (last) { |
| 304 | rawv6_rcv(last, skb); |
| 305 | read_unlock(&ip6_ra_lock); |
| 306 | return 1; |
| 307 | } |
| 308 | read_unlock(&ip6_ra_lock); |
| 309 | return 0; |
| 310 | } |
| 311 | |
| 312 | static inline int ip6_forward_finish(struct sk_buff *skb) |
| 313 | { |
| 314 | return dst_output(skb); |
| 315 | } |
| 316 | |
| 317 | int ip6_forward(struct sk_buff *skb) |
| 318 | { |
| 319 | struct dst_entry *dst = skb->dst; |
| 320 | struct ipv6hdr *hdr = skb->nh.ipv6h; |
| 321 | struct inet6_skb_parm *opt = IP6CB(skb); |
| 322 | |
| 323 | if (ipv6_devconf.forwarding == 0) |
| 324 | goto error; |
| 325 | |
| 326 | if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) { |
| 327 | IP6_INC_STATS(IPSTATS_MIB_INDISCARDS); |
| 328 | goto drop; |
| 329 | } |
| 330 | |
| 331 | skb->ip_summed = CHECKSUM_NONE; |
| 332 | |
| 333 | /* |
| 334 | * We DO NOT make any processing on |
| 335 | * RA packets, pushing them to user level AS IS |
| 336 | * without ane WARRANTY that application will be able |
| 337 | * to interpret them. The reason is that we |
| 338 | * cannot make anything clever here. |
| 339 | * |
| 340 | * We are not end-node, so that if packet contains |
| 341 | * AH/ESP, we cannot make anything. |
| 342 | * Defragmentation also would be mistake, RA packets |
| 343 | * cannot be fragmented, because there is no warranty |
| 344 | * that different fragments will go along one path. --ANK |
| 345 | */ |
| 346 | if (opt->ra) { |
| 347 | u8 *ptr = skb->nh.raw + opt->ra; |
| 348 | if (ip6_call_ra_chain(skb, (ptr[2]<<8) + ptr[3])) |
| 349 | return 0; |
| 350 | } |
| 351 | |
| 352 | /* |
| 353 | * check and decrement ttl |
| 354 | */ |
| 355 | if (hdr->hop_limit <= 1) { |
| 356 | /* Force OUTPUT device used as source address */ |
| 357 | skb->dev = dst->dev; |
| 358 | icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, |
| 359 | 0, skb->dev); |
| 360 | |
| 361 | kfree_skb(skb); |
| 362 | return -ETIMEDOUT; |
| 363 | } |
| 364 | |
| 365 | if (!xfrm6_route_forward(skb)) { |
| 366 | IP6_INC_STATS(IPSTATS_MIB_INDISCARDS); |
| 367 | goto drop; |
| 368 | } |
| 369 | dst = skb->dst; |
| 370 | |
| 371 | /* IPv6 specs say nothing about it, but it is clear that we cannot |
| 372 | send redirects to source routed frames. |
| 373 | */ |
| 374 | if (skb->dev == dst->dev && dst->neighbour && opt->srcrt == 0) { |
| 375 | struct in6_addr *target = NULL; |
| 376 | struct rt6_info *rt; |
| 377 | struct neighbour *n = dst->neighbour; |
| 378 | |
| 379 | /* |
| 380 | * incoming and outgoing devices are the same |
| 381 | * send a redirect. |
| 382 | */ |
| 383 | |
| 384 | rt = (struct rt6_info *) dst; |
| 385 | if ((rt->rt6i_flags & RTF_GATEWAY)) |
| 386 | target = (struct in6_addr*)&n->primary_key; |
| 387 | else |
| 388 | target = &hdr->daddr; |
| 389 | |
| 390 | /* Limit redirects both by destination (here) |
| 391 | and by source (inside ndisc_send_redirect) |
| 392 | */ |
| 393 | if (xrlim_allow(dst, 1*HZ)) |
| 394 | ndisc_send_redirect(skb, n, target); |
| 395 | } else if (ipv6_addr_type(&hdr->saddr)&(IPV6_ADDR_MULTICAST|IPV6_ADDR_LOOPBACK |
| 396 | |IPV6_ADDR_LINKLOCAL)) { |
| 397 | /* This check is security critical. */ |
| 398 | goto error; |
| 399 | } |
| 400 | |
| 401 | if (skb->len > dst_mtu(dst)) { |
| 402 | /* Again, force OUTPUT device used as source address */ |
| 403 | skb->dev = dst->dev; |
| 404 | icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, dst_mtu(dst), skb->dev); |
| 405 | IP6_INC_STATS_BH(IPSTATS_MIB_INTOOBIGERRORS); |
| 406 | IP6_INC_STATS_BH(IPSTATS_MIB_FRAGFAILS); |
| 407 | kfree_skb(skb); |
| 408 | return -EMSGSIZE; |
| 409 | } |
| 410 | |
| 411 | if (skb_cow(skb, dst->dev->hard_header_len)) { |
| 412 | IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS); |
| 413 | goto drop; |
| 414 | } |
| 415 | |
| 416 | hdr = skb->nh.ipv6h; |
| 417 | |
| 418 | /* Mangling hops number delayed to point after skb COW */ |
| 419 | |
| 420 | hdr->hop_limit--; |
| 421 | |
| 422 | IP6_INC_STATS_BH(IPSTATS_MIB_OUTFORWDATAGRAMS); |
| 423 | return NF_HOOK(PF_INET6,NF_IP6_FORWARD, skb, skb->dev, dst->dev, ip6_forward_finish); |
| 424 | |
| 425 | error: |
| 426 | IP6_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS); |
| 427 | drop: |
| 428 | kfree_skb(skb); |
| 429 | return -EINVAL; |
| 430 | } |
| 431 | |
| 432 | static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from) |
| 433 | { |
| 434 | to->pkt_type = from->pkt_type; |
| 435 | to->priority = from->priority; |
| 436 | to->protocol = from->protocol; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 437 | dst_release(to->dst); |
| 438 | to->dst = dst_clone(from->dst); |
| 439 | to->dev = from->dev; |
| 440 | |
| 441 | #ifdef CONFIG_NET_SCHED |
| 442 | to->tc_index = from->tc_index; |
| 443 | #endif |
| 444 | #ifdef CONFIG_NETFILTER |
| 445 | to->nfmark = from->nfmark; |
| 446 | /* Connection association is same as pre-frag packet */ |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 447 | nf_conntrack_put(to->nfct); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 448 | to->nfct = from->nfct; |
| 449 | nf_conntrack_get(to->nfct); |
| 450 | to->nfctinfo = from->nfctinfo; |
Yasuyuki Kozakai | 9fb9cbb | 2005-11-09 16:38:16 -0800 | [diff] [blame] | 451 | #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) |
| 452 | nf_conntrack_put_reasm(to->nfct_reasm); |
| 453 | to->nfct_reasm = from->nfct_reasm; |
| 454 | nf_conntrack_get_reasm(to->nfct_reasm); |
| 455 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 456 | #ifdef CONFIG_BRIDGE_NETFILTER |
| 457 | nf_bridge_put(to->nf_bridge); |
| 458 | to->nf_bridge = from->nf_bridge; |
| 459 | nf_bridge_get(to->nf_bridge); |
| 460 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 461 | #endif |
James Morris | 984bc16 | 2006-06-09 00:29:17 -0700 | [diff] [blame] | 462 | skb_copy_secmark(to, from); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 463 | } |
| 464 | |
| 465 | int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr) |
| 466 | { |
| 467 | u16 offset = sizeof(struct ipv6hdr); |
| 468 | struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr*)(skb->nh.ipv6h + 1); |
| 469 | unsigned int packet_len = skb->tail - skb->nh.raw; |
| 470 | int found_rhdr = 0; |
| 471 | *nexthdr = &skb->nh.ipv6h->nexthdr; |
| 472 | |
| 473 | while (offset + 1 <= packet_len) { |
| 474 | |
| 475 | switch (**nexthdr) { |
| 476 | |
| 477 | case NEXTHDR_HOP: |
| 478 | case NEXTHDR_ROUTING: |
| 479 | case NEXTHDR_DEST: |
| 480 | if (**nexthdr == NEXTHDR_ROUTING) found_rhdr = 1; |
| 481 | if (**nexthdr == NEXTHDR_DEST && found_rhdr) return offset; |
| 482 | offset += ipv6_optlen(exthdr); |
| 483 | *nexthdr = &exthdr->nexthdr; |
| 484 | exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset); |
| 485 | break; |
| 486 | default : |
| 487 | return offset; |
| 488 | } |
| 489 | } |
| 490 | |
| 491 | return offset; |
| 492 | } |
Herbert Xu | b59f45d | 2006-05-27 23:05:54 -0700 | [diff] [blame] | 493 | EXPORT_SYMBOL_GPL(ip6_find_1stfragopt); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 494 | |
| 495 | static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)) |
| 496 | { |
| 497 | struct net_device *dev; |
| 498 | struct sk_buff *frag; |
| 499 | struct rt6_info *rt = (struct rt6_info*)skb->dst; |
YOSHIFUJI Hideaki | d91675f | 2006-02-24 13:18:33 -0800 | [diff] [blame] | 500 | struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 501 | struct ipv6hdr *tmp_hdr; |
| 502 | struct frag_hdr *fh; |
| 503 | unsigned int mtu, hlen, left, len; |
| 504 | u32 frag_id = 0; |
| 505 | int ptr, offset = 0, err=0; |
| 506 | u8 *prevhdr, nexthdr = 0; |
| 507 | |
| 508 | dev = rt->u.dst.dev; |
| 509 | hlen = ip6_find_1stfragopt(skb, &prevhdr); |
| 510 | nexthdr = *prevhdr; |
| 511 | |
YOSHIFUJI Hideaki | d91675f | 2006-02-24 13:18:33 -0800 | [diff] [blame] | 512 | mtu = dst_mtu(&rt->u.dst); |
| 513 | if (np && np->frag_size < mtu) { |
| 514 | if (np->frag_size) |
| 515 | mtu = np->frag_size; |
| 516 | } |
| 517 | mtu -= hlen + sizeof(struct frag_hdr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 518 | |
| 519 | if (skb_shinfo(skb)->frag_list) { |
| 520 | int first_len = skb_pagelen(skb); |
| 521 | |
| 522 | if (first_len - hlen > mtu || |
| 523 | ((first_len - hlen) & 7) || |
| 524 | skb_cloned(skb)) |
| 525 | goto slow_path; |
| 526 | |
| 527 | for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next) { |
| 528 | /* Correct geometry. */ |
| 529 | if (frag->len > mtu || |
| 530 | ((frag->len & 7) && frag->next) || |
| 531 | skb_headroom(frag) < hlen) |
| 532 | goto slow_path; |
| 533 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 534 | /* Partially cloned skb? */ |
| 535 | if (skb_shared(frag)) |
| 536 | goto slow_path; |
Herbert Xu | 2fdba6b | 2005-05-18 22:52:33 -0700 | [diff] [blame] | 537 | |
| 538 | BUG_ON(frag->sk); |
| 539 | if (skb->sk) { |
| 540 | sock_hold(skb->sk); |
| 541 | frag->sk = skb->sk; |
| 542 | frag->destructor = sock_wfree; |
| 543 | skb->truesize -= frag->truesize; |
| 544 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 545 | } |
| 546 | |
| 547 | err = 0; |
| 548 | offset = 0; |
| 549 | frag = skb_shinfo(skb)->frag_list; |
| 550 | skb_shinfo(skb)->frag_list = NULL; |
| 551 | /* BUILD HEADER */ |
| 552 | |
| 553 | tmp_hdr = kmalloc(hlen, GFP_ATOMIC); |
| 554 | if (!tmp_hdr) { |
| 555 | IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS); |
| 556 | return -ENOMEM; |
| 557 | } |
| 558 | |
| 559 | *prevhdr = NEXTHDR_FRAGMENT; |
| 560 | memcpy(tmp_hdr, skb->nh.raw, hlen); |
| 561 | __skb_pull(skb, hlen); |
| 562 | fh = (struct frag_hdr*)__skb_push(skb, sizeof(struct frag_hdr)); |
| 563 | skb->nh.raw = __skb_push(skb, hlen); |
| 564 | memcpy(skb->nh.raw, tmp_hdr, hlen); |
| 565 | |
| 566 | ipv6_select_ident(skb, fh); |
| 567 | fh->nexthdr = nexthdr; |
| 568 | fh->reserved = 0; |
| 569 | fh->frag_off = htons(IP6_MF); |
| 570 | frag_id = fh->identification; |
| 571 | |
| 572 | first_len = skb_pagelen(skb); |
| 573 | skb->data_len = first_len - skb_headlen(skb); |
| 574 | skb->len = first_len; |
| 575 | skb->nh.ipv6h->payload_len = htons(first_len - sizeof(struct ipv6hdr)); |
| 576 | |
| 577 | |
| 578 | for (;;) { |
| 579 | /* Prepare header of the next frame, |
| 580 | * before previous one went down. */ |
| 581 | if (frag) { |
| 582 | frag->ip_summed = CHECKSUM_NONE; |
| 583 | frag->h.raw = frag->data; |
| 584 | fh = (struct frag_hdr*)__skb_push(frag, sizeof(struct frag_hdr)); |
| 585 | frag->nh.raw = __skb_push(frag, hlen); |
| 586 | memcpy(frag->nh.raw, tmp_hdr, hlen); |
| 587 | offset += skb->len - hlen - sizeof(struct frag_hdr); |
| 588 | fh->nexthdr = nexthdr; |
| 589 | fh->reserved = 0; |
| 590 | fh->frag_off = htons(offset); |
| 591 | if (frag->next != NULL) |
| 592 | fh->frag_off |= htons(IP6_MF); |
| 593 | fh->identification = frag_id; |
| 594 | frag->nh.ipv6h->payload_len = htons(frag->len - sizeof(struct ipv6hdr)); |
| 595 | ip6_copy_metadata(frag, skb); |
| 596 | } |
| 597 | |
| 598 | err = output(skb); |
| 599 | if (err || !frag) |
| 600 | break; |
| 601 | |
| 602 | skb = frag; |
| 603 | frag = skb->next; |
| 604 | skb->next = NULL; |
| 605 | } |
| 606 | |
Jesper Juhl | a51482b | 2005-11-08 09:41:34 -0800 | [diff] [blame] | 607 | kfree(tmp_hdr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 608 | |
| 609 | if (err == 0) { |
| 610 | IP6_INC_STATS(IPSTATS_MIB_FRAGOKS); |
| 611 | return 0; |
| 612 | } |
| 613 | |
| 614 | while (frag) { |
| 615 | skb = frag->next; |
| 616 | kfree_skb(frag); |
| 617 | frag = skb; |
| 618 | } |
| 619 | |
| 620 | IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS); |
| 621 | return err; |
| 622 | } |
| 623 | |
| 624 | slow_path: |
| 625 | left = skb->len - hlen; /* Space per frame */ |
| 626 | ptr = hlen; /* Where to start from */ |
| 627 | |
| 628 | /* |
| 629 | * Fragment the datagram. |
| 630 | */ |
| 631 | |
| 632 | *prevhdr = NEXTHDR_FRAGMENT; |
| 633 | |
| 634 | /* |
| 635 | * Keep copying data until we run out. |
| 636 | */ |
| 637 | while(left > 0) { |
| 638 | len = left; |
| 639 | /* IF: it doesn't fit, use 'mtu' - the data space left */ |
| 640 | if (len > mtu) |
| 641 | len = mtu; |
| 642 | /* IF: we are not sending upto and including the packet end |
| 643 | then align the next start on an eight byte boundary */ |
| 644 | if (len < left) { |
| 645 | len &= ~7; |
| 646 | } |
| 647 | /* |
| 648 | * Allocate buffer. |
| 649 | */ |
| 650 | |
| 651 | if ((frag = alloc_skb(len+hlen+sizeof(struct frag_hdr)+LL_RESERVED_SPACE(rt->u.dst.dev), GFP_ATOMIC)) == NULL) { |
Patrick McHardy | 64ce207 | 2005-08-09 20:50:53 -0700 | [diff] [blame] | 652 | NETDEBUG(KERN_INFO "IPv6: frag: no memory for new fragment!\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 653 | IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS); |
| 654 | err = -ENOMEM; |
| 655 | goto fail; |
| 656 | } |
| 657 | |
| 658 | /* |
| 659 | * Set up data on packet |
| 660 | */ |
| 661 | |
| 662 | ip6_copy_metadata(frag, skb); |
| 663 | skb_reserve(frag, LL_RESERVED_SPACE(rt->u.dst.dev)); |
| 664 | skb_put(frag, len + hlen + sizeof(struct frag_hdr)); |
| 665 | frag->nh.raw = frag->data; |
| 666 | fh = (struct frag_hdr*)(frag->data + hlen); |
| 667 | frag->h.raw = frag->data + hlen + sizeof(struct frag_hdr); |
| 668 | |
| 669 | /* |
| 670 | * Charge the memory for the fragment to any owner |
| 671 | * it might possess |
| 672 | */ |
| 673 | if (skb->sk) |
| 674 | skb_set_owner_w(frag, skb->sk); |
| 675 | |
| 676 | /* |
| 677 | * Copy the packet header into the new buffer. |
| 678 | */ |
| 679 | memcpy(frag->nh.raw, skb->data, hlen); |
| 680 | |
| 681 | /* |
| 682 | * Build fragment header. |
| 683 | */ |
| 684 | fh->nexthdr = nexthdr; |
| 685 | fh->reserved = 0; |
Yan Zheng | f36d6ab | 2005-10-03 14:19:15 -0700 | [diff] [blame] | 686 | if (!frag_id) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 687 | ipv6_select_ident(skb, fh); |
| 688 | frag_id = fh->identification; |
| 689 | } else |
| 690 | fh->identification = frag_id; |
| 691 | |
| 692 | /* |
| 693 | * Copy a block of the IP datagram. |
| 694 | */ |
| 695 | if (skb_copy_bits(skb, ptr, frag->h.raw, len)) |
| 696 | BUG(); |
| 697 | left -= len; |
| 698 | |
| 699 | fh->frag_off = htons(offset); |
| 700 | if (left > 0) |
| 701 | fh->frag_off |= htons(IP6_MF); |
| 702 | frag->nh.ipv6h->payload_len = htons(frag->len - sizeof(struct ipv6hdr)); |
| 703 | |
| 704 | ptr += len; |
| 705 | offset += len; |
| 706 | |
| 707 | /* |
| 708 | * Put this fragment into the sending queue. |
| 709 | */ |
| 710 | |
| 711 | IP6_INC_STATS(IPSTATS_MIB_FRAGCREATES); |
| 712 | |
| 713 | err = output(frag); |
| 714 | if (err) |
| 715 | goto fail; |
| 716 | } |
| 717 | kfree_skb(skb); |
| 718 | IP6_INC_STATS(IPSTATS_MIB_FRAGOKS); |
| 719 | return err; |
| 720 | |
| 721 | fail: |
| 722 | kfree_skb(skb); |
| 723 | IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS); |
| 724 | return err; |
| 725 | } |
| 726 | |
| 727 | int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl) |
| 728 | { |
| 729 | int err = 0; |
| 730 | |
| 731 | *dst = NULL; |
| 732 | if (sk) { |
| 733 | struct ipv6_pinfo *np = inet6_sk(sk); |
| 734 | |
| 735 | *dst = sk_dst_check(sk, np->dst_cookie); |
| 736 | if (*dst) { |
| 737 | struct rt6_info *rt = (struct rt6_info*)*dst; |
| 738 | |
David S. Miller | d76e60a | 2006-03-20 21:35:50 -0800 | [diff] [blame] | 739 | /* Yes, checking route validity in not connected |
| 740 | * case is not very simple. Take into account, |
| 741 | * that we do not support routing by source, TOS, |
| 742 | * and MSG_DONTROUTE --ANK (980726) |
| 743 | * |
| 744 | * 1. If route was host route, check that |
| 745 | * cached destination is current. |
| 746 | * If it is network route, we still may |
| 747 | * check its validity using saved pointer |
| 748 | * to the last used address: daddr_cache. |
| 749 | * We do not want to save whole address now, |
| 750 | * (because main consumer of this service |
| 751 | * is tcp, which has not this problem), |
| 752 | * so that the last trick works only on connected |
| 753 | * sockets. |
| 754 | * 2. oif also should be the same. |
| 755 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 756 | if (((rt->rt6i_dst.plen != 128 || |
David S. Miller | d76e60a | 2006-03-20 21:35:50 -0800 | [diff] [blame] | 757 | !ipv6_addr_equal(&fl->fl6_dst, |
| 758 | &rt->rt6i_dst.addr)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 759 | && (np->daddr_cache == NULL || |
David S. Miller | d76e60a | 2006-03-20 21:35:50 -0800 | [diff] [blame] | 760 | !ipv6_addr_equal(&fl->fl6_dst, |
| 761 | np->daddr_cache))) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 762 | || (fl->oif && fl->oif != (*dst)->dev->ifindex)) { |
| 763 | dst_release(*dst); |
| 764 | *dst = NULL; |
| 765 | } |
| 766 | } |
| 767 | } |
| 768 | |
| 769 | if (*dst == NULL) |
| 770 | *dst = ip6_route_output(sk, fl); |
| 771 | |
| 772 | if ((err = (*dst)->error)) |
| 773 | goto out_err_release; |
| 774 | |
| 775 | if (ipv6_addr_any(&fl->fl6_src)) { |
| 776 | err = ipv6_get_saddr(*dst, &fl->fl6_dst, &fl->fl6_src); |
| 777 | |
Olaf Hering | 44456d3 | 2005-07-27 11:45:17 -0700 | [diff] [blame] | 778 | if (err) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 779 | goto out_err_release; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 780 | } |
| 781 | |
| 782 | return 0; |
| 783 | |
| 784 | out_err_release: |
| 785 | dst_release(*dst); |
| 786 | *dst = NULL; |
| 787 | return err; |
| 788 | } |
Adrian Bunk | 34a0b3c | 2005-11-29 16:28:56 -0800 | [diff] [blame] | 789 | |
Arnaldo Carvalho de Melo | 3cf3dc6 | 2005-12-13 23:23:20 -0800 | [diff] [blame] | 790 | EXPORT_SYMBOL_GPL(ip6_dst_lookup); |
| 791 | |
Adrian Bunk | 34a0b3c | 2005-11-29 16:28:56 -0800 | [diff] [blame] | 792 | static inline int ip6_ufo_append_data(struct sock *sk, |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 793 | int getfrag(void *from, char *to, int offset, int len, |
| 794 | int odd, struct sk_buff *skb), |
| 795 | void *from, int length, int hh_len, int fragheaderlen, |
| 796 | int transhdrlen, int mtu,unsigned int flags) |
| 797 | |
| 798 | { |
| 799 | struct sk_buff *skb; |
| 800 | int err; |
| 801 | |
| 802 | /* There is support for UDP large send offload by network |
| 803 | * device, so create one single skb packet containing complete |
| 804 | * udp datagram |
| 805 | */ |
| 806 | if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) { |
| 807 | skb = sock_alloc_send_skb(sk, |
| 808 | hh_len + fragheaderlen + transhdrlen + 20, |
| 809 | (flags & MSG_DONTWAIT), &err); |
| 810 | if (skb == NULL) |
| 811 | return -ENOMEM; |
| 812 | |
| 813 | /* reserve space for Hardware header */ |
| 814 | skb_reserve(skb, hh_len); |
| 815 | |
| 816 | /* create space for UDP/IP header */ |
| 817 | skb_put(skb,fragheaderlen + transhdrlen); |
| 818 | |
| 819 | /* initialize network header pointer */ |
| 820 | skb->nh.raw = skb->data; |
| 821 | |
| 822 | /* initialize protocol header pointer */ |
| 823 | skb->h.raw = skb->data + fragheaderlen; |
| 824 | |
| 825 | skb->ip_summed = CHECKSUM_HW; |
| 826 | skb->csum = 0; |
| 827 | sk->sk_sndmsg_off = 0; |
| 828 | } |
| 829 | |
| 830 | err = skb_append_datato_frags(sk,skb, getfrag, from, |
| 831 | (length - transhdrlen)); |
| 832 | if (!err) { |
| 833 | struct frag_hdr fhdr; |
| 834 | |
| 835 | /* specify the length of each IP datagram fragment*/ |
Herbert Xu | 7967168 | 2006-06-22 02:40:14 -0700 | [diff] [blame] | 836 | skb_shinfo(skb)->gso_size = mtu - fragheaderlen - |
| 837 | sizeof(struct frag_hdr); |
| 838 | skb_shinfo(skb)->gso_type = SKB_GSO_UDPV4; |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 839 | ipv6_select_ident(skb, &fhdr); |
| 840 | skb_shinfo(skb)->ip6_frag_id = fhdr.identification; |
| 841 | __skb_queue_tail(&sk->sk_write_queue, skb); |
| 842 | |
| 843 | return 0; |
| 844 | } |
| 845 | /* There is not enough support do UPD LSO, |
| 846 | * so follow normal path |
| 847 | */ |
| 848 | kfree_skb(skb); |
| 849 | |
| 850 | return err; |
| 851 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 852 | |
YOSHIFUJI Hideaki | 41a1f8e | 2005-09-08 10:19:03 +0900 | [diff] [blame] | 853 | int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to, |
| 854 | int offset, int len, int odd, struct sk_buff *skb), |
| 855 | void *from, int length, int transhdrlen, |
| 856 | int hlimit, int tclass, struct ipv6_txoptions *opt, struct flowi *fl, |
| 857 | struct rt6_info *rt, unsigned int flags) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 858 | { |
| 859 | struct inet_sock *inet = inet_sk(sk); |
| 860 | struct ipv6_pinfo *np = inet6_sk(sk); |
| 861 | struct sk_buff *skb; |
| 862 | unsigned int maxfraglen, fragheaderlen; |
| 863 | int exthdrlen; |
| 864 | int hh_len; |
| 865 | int mtu; |
| 866 | int copy; |
| 867 | int err; |
| 868 | int offset = 0; |
| 869 | int csummode = CHECKSUM_NONE; |
| 870 | |
| 871 | if (flags&MSG_PROBE) |
| 872 | return 0; |
| 873 | if (skb_queue_empty(&sk->sk_write_queue)) { |
| 874 | /* |
| 875 | * setup for corking |
| 876 | */ |
| 877 | if (opt) { |
| 878 | if (np->cork.opt == NULL) { |
| 879 | np->cork.opt = kmalloc(opt->tot_len, |
| 880 | sk->sk_allocation); |
| 881 | if (unlikely(np->cork.opt == NULL)) |
| 882 | return -ENOBUFS; |
| 883 | } else if (np->cork.opt->tot_len < opt->tot_len) { |
| 884 | printk(KERN_DEBUG "ip6_append_data: invalid option length\n"); |
| 885 | return -EINVAL; |
| 886 | } |
| 887 | memcpy(np->cork.opt, opt, opt->tot_len); |
| 888 | inet->cork.flags |= IPCORK_OPT; |
| 889 | /* need source address above miyazawa*/ |
| 890 | } |
| 891 | dst_hold(&rt->u.dst); |
| 892 | np->cork.rt = rt; |
| 893 | inet->cork.fl = *fl; |
| 894 | np->cork.hop_limit = hlimit; |
YOSHIFUJI Hideaki | 41a1f8e | 2005-09-08 10:19:03 +0900 | [diff] [blame] | 895 | np->cork.tclass = tclass; |
YOSHIFUJI Hideaki | d91675f | 2006-02-24 13:18:33 -0800 | [diff] [blame] | 896 | mtu = dst_mtu(rt->u.dst.path); |
Dave Jones | c750360 | 2006-03-20 22:44:52 -0800 | [diff] [blame] | 897 | if (np->frag_size < mtu) { |
YOSHIFUJI Hideaki | d91675f | 2006-02-24 13:18:33 -0800 | [diff] [blame] | 898 | if (np->frag_size) |
| 899 | mtu = np->frag_size; |
| 900 | } |
| 901 | inet->cork.fragsize = mtu; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 902 | if (dst_allfrag(rt->u.dst.path)) |
| 903 | inet->cork.flags |= IPCORK_ALLFRAG; |
| 904 | inet->cork.length = 0; |
| 905 | sk->sk_sndmsg_page = NULL; |
| 906 | sk->sk_sndmsg_off = 0; |
| 907 | exthdrlen = rt->u.dst.header_len + (opt ? opt->opt_flen : 0); |
| 908 | length += exthdrlen; |
| 909 | transhdrlen += exthdrlen; |
| 910 | } else { |
| 911 | rt = np->cork.rt; |
| 912 | fl = &inet->cork.fl; |
| 913 | if (inet->cork.flags & IPCORK_OPT) |
| 914 | opt = np->cork.opt; |
| 915 | transhdrlen = 0; |
| 916 | exthdrlen = 0; |
| 917 | mtu = inet->cork.fragsize; |
| 918 | } |
| 919 | |
| 920 | hh_len = LL_RESERVED_SPACE(rt->u.dst.dev); |
| 921 | |
| 922 | fragheaderlen = sizeof(struct ipv6hdr) + (opt ? opt->opt_nflen : 0); |
| 923 | maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr); |
| 924 | |
| 925 | if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) { |
| 926 | if (inet->cork.length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) { |
| 927 | ipv6_local_error(sk, EMSGSIZE, fl, mtu-exthdrlen); |
| 928 | return -EMSGSIZE; |
| 929 | } |
| 930 | } |
| 931 | |
| 932 | /* |
| 933 | * Let's try using as much space as possible. |
| 934 | * Use MTU if total length of the message fits into the MTU. |
| 935 | * Otherwise, we need to reserve fragment header and |
| 936 | * fragment alignment (= 8-15 octects, in total). |
| 937 | * |
| 938 | * Note that we may need to "move" the data from the tail of |
| 939 | * of the buffer to the new fragment when we split |
| 940 | * the message. |
| 941 | * |
| 942 | * FIXME: It may be fragmented into multiple chunks |
| 943 | * at once if non-fragmentable extension headers |
| 944 | * are too large. |
| 945 | * --yoshfuji |
| 946 | */ |
| 947 | |
| 948 | inet->cork.length += length; |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 949 | if (((length > mtu) && (sk->sk_protocol == IPPROTO_UDP)) && |
| 950 | (rt->u.dst.dev->features & NETIF_F_UFO)) { |
| 951 | |
Patrick McHardy | baa829d | 2006-03-12 20:35:12 -0800 | [diff] [blame] | 952 | err = ip6_ufo_append_data(sk, getfrag, from, length, hh_len, |
| 953 | fragheaderlen, transhdrlen, mtu, |
| 954 | flags); |
| 955 | if (err) |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 956 | goto error; |
Ananda Raju | e89e9cf | 2005-10-18 15:46:41 -0700 | [diff] [blame] | 957 | return 0; |
| 958 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 959 | |
| 960 | if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) |
| 961 | goto alloc_new_skb; |
| 962 | |
| 963 | while (length > 0) { |
| 964 | /* Check if the remaining data fits into current packet. */ |
| 965 | copy = (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len; |
| 966 | if (copy < length) |
| 967 | copy = maxfraglen - skb->len; |
| 968 | |
| 969 | if (copy <= 0) { |
| 970 | char *data; |
| 971 | unsigned int datalen; |
| 972 | unsigned int fraglen; |
| 973 | unsigned int fraggap; |
| 974 | unsigned int alloclen; |
| 975 | struct sk_buff *skb_prev; |
| 976 | alloc_new_skb: |
| 977 | skb_prev = skb; |
| 978 | |
| 979 | /* There's no room in the current skb */ |
| 980 | if (skb_prev) |
| 981 | fraggap = skb_prev->len - maxfraglen; |
| 982 | else |
| 983 | fraggap = 0; |
| 984 | |
| 985 | /* |
| 986 | * If remaining data exceeds the mtu, |
| 987 | * we know we need more fragment(s). |
| 988 | */ |
| 989 | datalen = length + fraggap; |
| 990 | if (datalen > (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen) |
| 991 | datalen = maxfraglen - fragheaderlen; |
| 992 | |
| 993 | fraglen = datalen + fragheaderlen; |
| 994 | if ((flags & MSG_MORE) && |
| 995 | !(rt->u.dst.dev->features&NETIF_F_SG)) |
| 996 | alloclen = mtu; |
| 997 | else |
| 998 | alloclen = datalen + fragheaderlen; |
| 999 | |
| 1000 | /* |
| 1001 | * The last fragment gets additional space at tail. |
| 1002 | * Note: we overallocate on fragments with MSG_MODE |
| 1003 | * because we have no idea if we're the last one. |
| 1004 | */ |
| 1005 | if (datalen == length + fraggap) |
| 1006 | alloclen += rt->u.dst.trailer_len; |
| 1007 | |
| 1008 | /* |
| 1009 | * We just reserve space for fragment header. |
| 1010 | * Note: this may be overallocation if the message |
| 1011 | * (without MSG_MORE) fits into the MTU. |
| 1012 | */ |
| 1013 | alloclen += sizeof(struct frag_hdr); |
| 1014 | |
| 1015 | if (transhdrlen) { |
| 1016 | skb = sock_alloc_send_skb(sk, |
| 1017 | alloclen + hh_len, |
| 1018 | (flags & MSG_DONTWAIT), &err); |
| 1019 | } else { |
| 1020 | skb = NULL; |
| 1021 | if (atomic_read(&sk->sk_wmem_alloc) <= |
| 1022 | 2 * sk->sk_sndbuf) |
| 1023 | skb = sock_wmalloc(sk, |
| 1024 | alloclen + hh_len, 1, |
| 1025 | sk->sk_allocation); |
| 1026 | if (unlikely(skb == NULL)) |
| 1027 | err = -ENOBUFS; |
| 1028 | } |
| 1029 | if (skb == NULL) |
| 1030 | goto error; |
| 1031 | /* |
| 1032 | * Fill in the control structures |
| 1033 | */ |
| 1034 | skb->ip_summed = csummode; |
| 1035 | skb->csum = 0; |
| 1036 | /* reserve for fragmentation */ |
| 1037 | skb_reserve(skb, hh_len+sizeof(struct frag_hdr)); |
| 1038 | |
| 1039 | /* |
| 1040 | * Find where to start putting bytes |
| 1041 | */ |
| 1042 | data = skb_put(skb, fraglen); |
| 1043 | skb->nh.raw = data + exthdrlen; |
| 1044 | data += fragheaderlen; |
| 1045 | skb->h.raw = data + exthdrlen; |
| 1046 | |
| 1047 | if (fraggap) { |
| 1048 | skb->csum = skb_copy_and_csum_bits( |
| 1049 | skb_prev, maxfraglen, |
| 1050 | data + transhdrlen, fraggap, 0); |
| 1051 | skb_prev->csum = csum_sub(skb_prev->csum, |
| 1052 | skb->csum); |
| 1053 | data += fraggap; |
| 1054 | skb_trim(skb_prev, maxfraglen); |
| 1055 | } |
| 1056 | copy = datalen - transhdrlen - fraggap; |
| 1057 | if (copy < 0) { |
| 1058 | err = -EINVAL; |
| 1059 | kfree_skb(skb); |
| 1060 | goto error; |
| 1061 | } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) { |
| 1062 | err = -EFAULT; |
| 1063 | kfree_skb(skb); |
| 1064 | goto error; |
| 1065 | } |
| 1066 | |
| 1067 | offset += copy; |
| 1068 | length -= datalen - fraggap; |
| 1069 | transhdrlen = 0; |
| 1070 | exthdrlen = 0; |
| 1071 | csummode = CHECKSUM_NONE; |
| 1072 | |
| 1073 | /* |
| 1074 | * Put the packet on the pending queue |
| 1075 | */ |
| 1076 | __skb_queue_tail(&sk->sk_write_queue, skb); |
| 1077 | continue; |
| 1078 | } |
| 1079 | |
| 1080 | if (copy > length) |
| 1081 | copy = length; |
| 1082 | |
| 1083 | if (!(rt->u.dst.dev->features&NETIF_F_SG)) { |
| 1084 | unsigned int off; |
| 1085 | |
| 1086 | off = skb->len; |
| 1087 | if (getfrag(from, skb_put(skb, copy), |
| 1088 | offset, copy, off, skb) < 0) { |
| 1089 | __skb_trim(skb, off); |
| 1090 | err = -EFAULT; |
| 1091 | goto error; |
| 1092 | } |
| 1093 | } else { |
| 1094 | int i = skb_shinfo(skb)->nr_frags; |
| 1095 | skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1]; |
| 1096 | struct page *page = sk->sk_sndmsg_page; |
| 1097 | int off = sk->sk_sndmsg_off; |
| 1098 | unsigned int left; |
| 1099 | |
| 1100 | if (page && (left = PAGE_SIZE - off) > 0) { |
| 1101 | if (copy >= left) |
| 1102 | copy = left; |
| 1103 | if (page != frag->page) { |
| 1104 | if (i == MAX_SKB_FRAGS) { |
| 1105 | err = -EMSGSIZE; |
| 1106 | goto error; |
| 1107 | } |
| 1108 | get_page(page); |
| 1109 | skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0); |
| 1110 | frag = &skb_shinfo(skb)->frags[i]; |
| 1111 | } |
| 1112 | } else if(i < MAX_SKB_FRAGS) { |
| 1113 | if (copy > PAGE_SIZE) |
| 1114 | copy = PAGE_SIZE; |
| 1115 | page = alloc_pages(sk->sk_allocation, 0); |
| 1116 | if (page == NULL) { |
| 1117 | err = -ENOMEM; |
| 1118 | goto error; |
| 1119 | } |
| 1120 | sk->sk_sndmsg_page = page; |
| 1121 | sk->sk_sndmsg_off = 0; |
| 1122 | |
| 1123 | skb_fill_page_desc(skb, i, page, 0, 0); |
| 1124 | frag = &skb_shinfo(skb)->frags[i]; |
| 1125 | skb->truesize += PAGE_SIZE; |
| 1126 | atomic_add(PAGE_SIZE, &sk->sk_wmem_alloc); |
| 1127 | } else { |
| 1128 | err = -EMSGSIZE; |
| 1129 | goto error; |
| 1130 | } |
| 1131 | if (getfrag(from, page_address(frag->page)+frag->page_offset+frag->size, offset, copy, skb->len, skb) < 0) { |
| 1132 | err = -EFAULT; |
| 1133 | goto error; |
| 1134 | } |
| 1135 | sk->sk_sndmsg_off += copy; |
| 1136 | frag->size += copy; |
| 1137 | skb->len += copy; |
| 1138 | skb->data_len += copy; |
| 1139 | } |
| 1140 | offset += copy; |
| 1141 | length -= copy; |
| 1142 | } |
| 1143 | return 0; |
| 1144 | error: |
| 1145 | inet->cork.length -= length; |
| 1146 | IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS); |
| 1147 | return err; |
| 1148 | } |
| 1149 | |
| 1150 | int ip6_push_pending_frames(struct sock *sk) |
| 1151 | { |
| 1152 | struct sk_buff *skb, *tmp_skb; |
| 1153 | struct sk_buff **tail_skb; |
| 1154 | struct in6_addr final_dst_buf, *final_dst = &final_dst_buf; |
| 1155 | struct inet_sock *inet = inet_sk(sk); |
| 1156 | struct ipv6_pinfo *np = inet6_sk(sk); |
| 1157 | struct ipv6hdr *hdr; |
| 1158 | struct ipv6_txoptions *opt = np->cork.opt; |
| 1159 | struct rt6_info *rt = np->cork.rt; |
| 1160 | struct flowi *fl = &inet->cork.fl; |
| 1161 | unsigned char proto = fl->proto; |
| 1162 | int err = 0; |
| 1163 | |
| 1164 | if ((skb = __skb_dequeue(&sk->sk_write_queue)) == NULL) |
| 1165 | goto out; |
| 1166 | tail_skb = &(skb_shinfo(skb)->frag_list); |
| 1167 | |
| 1168 | /* move skb->data to ip header from ext header */ |
| 1169 | if (skb->data < skb->nh.raw) |
| 1170 | __skb_pull(skb, skb->nh.raw - skb->data); |
| 1171 | while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) { |
| 1172 | __skb_pull(tmp_skb, skb->h.raw - skb->nh.raw); |
| 1173 | *tail_skb = tmp_skb; |
| 1174 | tail_skb = &(tmp_skb->next); |
| 1175 | skb->len += tmp_skb->len; |
| 1176 | skb->data_len += tmp_skb->len; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1177 | skb->truesize += tmp_skb->truesize; |
| 1178 | __sock_put(tmp_skb->sk); |
| 1179 | tmp_skb->destructor = NULL; |
| 1180 | tmp_skb->sk = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1181 | } |
| 1182 | |
| 1183 | ipv6_addr_copy(final_dst, &fl->fl6_dst); |
| 1184 | __skb_pull(skb, skb->h.raw - skb->nh.raw); |
| 1185 | if (opt && opt->opt_flen) |
| 1186 | ipv6_push_frag_opts(skb, opt, &proto); |
| 1187 | if (opt && opt->opt_nflen) |
| 1188 | ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst); |
| 1189 | |
| 1190 | skb->nh.ipv6h = hdr = (struct ipv6hdr*) skb_push(skb, sizeof(struct ipv6hdr)); |
| 1191 | |
YOSHIFUJI Hideaki | 41a1f8e | 2005-09-08 10:19:03 +0900 | [diff] [blame] | 1192 | *(u32*)hdr = fl->fl6_flowlabel | |
| 1193 | htonl(0x60000000 | ((int)np->cork.tclass << 20)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1194 | |
| 1195 | if (skb->len <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) |
| 1196 | hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); |
| 1197 | else |
| 1198 | hdr->payload_len = 0; |
| 1199 | hdr->hop_limit = np->cork.hop_limit; |
| 1200 | hdr->nexthdr = proto; |
| 1201 | ipv6_addr_copy(&hdr->saddr, &fl->fl6_src); |
| 1202 | ipv6_addr_copy(&hdr->daddr, final_dst); |
| 1203 | |
Patrick McHardy | a2c2064 | 2006-01-08 22:37:26 -0800 | [diff] [blame] | 1204 | skb->priority = sk->sk_priority; |
| 1205 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1206 | skb->dst = dst_clone(&rt->u.dst); |
| 1207 | IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS); |
| 1208 | err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, skb->dst->dev, dst_output); |
| 1209 | if (err) { |
| 1210 | if (err > 0) |
Herbert Xu | 3320da8 | 2005-04-19 22:32:22 -0700 | [diff] [blame] | 1211 | err = np->recverr ? net_xmit_errno(err) : 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1212 | if (err) |
| 1213 | goto error; |
| 1214 | } |
| 1215 | |
| 1216 | out: |
| 1217 | inet->cork.flags &= ~IPCORK_OPT; |
Jesper Juhl | a51482b | 2005-11-08 09:41:34 -0800 | [diff] [blame] | 1218 | kfree(np->cork.opt); |
| 1219 | np->cork.opt = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1220 | if (np->cork.rt) { |
| 1221 | dst_release(&np->cork.rt->u.dst); |
| 1222 | np->cork.rt = NULL; |
| 1223 | inet->cork.flags &= ~IPCORK_ALLFRAG; |
| 1224 | } |
| 1225 | memset(&inet->cork.fl, 0, sizeof(inet->cork.fl)); |
| 1226 | return err; |
| 1227 | error: |
| 1228 | goto out; |
| 1229 | } |
| 1230 | |
| 1231 | void ip6_flush_pending_frames(struct sock *sk) |
| 1232 | { |
| 1233 | struct inet_sock *inet = inet_sk(sk); |
| 1234 | struct ipv6_pinfo *np = inet6_sk(sk); |
| 1235 | struct sk_buff *skb; |
| 1236 | |
| 1237 | while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) { |
| 1238 | IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS); |
| 1239 | kfree_skb(skb); |
| 1240 | } |
| 1241 | |
| 1242 | inet->cork.flags &= ~IPCORK_OPT; |
| 1243 | |
Jesper Juhl | a51482b | 2005-11-08 09:41:34 -0800 | [diff] [blame] | 1244 | kfree(np->cork.opt); |
| 1245 | np->cork.opt = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1246 | if (np->cork.rt) { |
| 1247 | dst_release(&np->cork.rt->u.dst); |
| 1248 | np->cork.rt = NULL; |
| 1249 | inet->cork.flags &= ~IPCORK_ALLFRAG; |
| 1250 | } |
| 1251 | memset(&inet->cork.fl, 0, sizeof(inet->cork.fl)); |
| 1252 | } |