1 /* 2 * INET An implementation of the TCP/IP protocol suite for the LINUX 3 * operating system. INET is implemented using the BSD Socket 4 * interface as the means of communication with the user level. 5 * 6 * The Internet Protocol (IP) output module. 7 * 8 * Version: $Id: ip_output.c,v 1.100 2002/02/01 22:01:03 davem Exp $ 9 * 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * Donald Becker, <becker@super.org> 13 * Alan Cox, <Alan.Cox@linux.org> 14 * Richard Underwood 15 * Stefan Becker, <stefanb@yello.ping.de> 16 * Jorge Cwik, <jorge@laser.satlink.net> 17 * Arnt Gulbrandsen, <agulbra@nvg.unit.no> 18 * Hirokazu Takahashi, <taka@valinux.co.jp> 19 * 20 * See ip_input.c for original log 21 * 22 * Fixes: 23 * Alan Cox : Missing nonblock feature in ip_build_xmit. 24 * Mike Kilburn : htons() missing in ip_build_xmit. 25 * Bradford Johnson: Fix faulty handling of some frames when 26 * no route is found. 27 * Alexander Demenshin: Missing sk/skb free in ip_queue_xmit 28 * (in case if packet not accepted by 29 * output firewall rules) 30 * Mike McLagan : Routing by source 31 * Alexey Kuznetsov: use new route cache 32 * Andi Kleen: Fix broken PMTU recovery and remove 33 * some redundant tests. 34 * Vitaly E. Lavrov : Transparent proxy revived after year coma. 35 * Andi Kleen : Replace ip_reply with ip_send_reply. 36 * Andi Kleen : Split fast and slow ip_build_xmit path 37 * for decreased register pressure on x86 38 * and more readibility. 39 * Marc Boucher : When call_out_firewall returns FW_QUEUE, 40 * silently drop skb instead of failing with -EPERM. 41 * Detlev Wengorz : Copy protocol for fragments. 42 * Hirokazu Takahashi: HW checksumming for outgoing UDP 43 * datagrams. 44 * Hirokazu Takahashi: sendfile() on UDP works now. 45 */ 46 47 #include <asm/uaccess.h> 48 #include <asm/system.h> 49 #include <linux/module.h> 50 #include <linux/types.h> 51 #include <linux/kernel.h> 52 #include <linux/sched.h> 53 #include <linux/mm.h> 54 #include <linux/string.h> 55 #include <linux/errno.h> 56 #include <linux/config.h> 57 58 #include <linux/socket.h> 59 #include <linux/sockios.h> 60 #include <linux/in.h> 61 #include <linux/inet.h> 62 #include <linux/netdevice.h> 63 #include <linux/etherdevice.h> 64 #include <linux/proc_fs.h> 65 #include <linux/stat.h> 66 #include <linux/init.h> 67 68 #include <net/snmp.h> 69 #include <net/ip.h> 70 #include <net/protocol.h> 71 #include <net/route.h> 72 #include <net/xfrm.h> 73 #include <linux/skbuff.h> 74 #include <net/sock.h> 75 #include <net/arp.h> 76 #include <net/icmp.h> 77 #include <net/checksum.h> 78 #include <net/inetpeer.h> 79 #include <net/checksum.h> 80 #include <linux/igmp.h> 81 #include <linux/netfilter_ipv4.h> 82 #include <linux/netfilter_bridge.h> 83 #include <linux/mroute.h> 84 #include <linux/netlink.h> 85 #include <linux/tcp.h> 86 87 int sysctl_ip_default_ttl = IPDEFTTL; 88 89 static int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff*)); 90 91 /* Generate a checksum for an outgoing IP datagram. */ 92 __inline__ void ip_send_check(struct iphdr *iph) 93 { 94 iph->check = 0; 95 iph->check = ip_fast_csum((unsigned char *)iph, iph->ihl); 96 } 97 98 /* dev_loopback_xmit for use with netfilter. */ 99 static int ip_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 netif_rx(newskb); 107 return 0; 108 } 109 110 static inline int ip_select_ttl(struct inet_sock *inet, struct dst_entry *dst) 111 { 112 int ttl = inet->uc_ttl; 113 114 if (ttl < 0) 115 ttl = dst_metric(dst, RTAX_HOPLIMIT); 116 return ttl; 117 } 118 119 /* 120 * Add an ip header to a skbuff and send it out. 121 * 122 */ 123 int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk, 124 u32 saddr, u32 daddr, struct ip_options *opt) 125 { 126 struct inet_sock *inet = inet_sk(sk); 127 struct rtable *rt = (struct rtable *)skb->dst; 128 struct iphdr *iph; 129 130 /* Build the IP header. */ 131 if (opt) 132 iph=(struct iphdr *)skb_push(skb,sizeof(struct iphdr) + opt->optlen); 133 else 134 iph=(struct iphdr *)skb_push(skb,sizeof(struct iphdr)); 135 136 iph->version = 4; 137 iph->ihl = 5; 138 iph->tos = inet->tos; 139 if (ip_dont_fragment(sk, &rt->u.dst)) 140 iph->frag_off = htons(IP_DF); 141 else 142 iph->frag_off = 0; 143 iph->ttl = ip_select_ttl(inet, &rt->u.dst); 144 iph->daddr = rt->rt_dst; 145 iph->saddr = rt->rt_src; 146 iph->protocol = sk->sk_protocol; 147 iph->tot_len = htons(skb->len); 148 ip_select_ident(iph, &rt->u.dst, sk); 149 skb->nh.iph = iph; 150 151 if (opt && opt->optlen) { 152 iph->ihl += opt->optlen>>2; 153 ip_options_build(skb, opt, daddr, rt, 0); 154 } 155 ip_send_check(iph); 156 157 skb->priority = sk->sk_priority; 158 159 /* Send it out. */ 160 return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, rt->u.dst.dev, 161 dst_output); 162 } 163 164 EXPORT_SYMBOL_GPL(ip_build_and_send_pkt); 165 166 static inline int ip_finish_output2(struct sk_buff *skb) 167 { 168 struct dst_entry *dst = skb->dst; 169 struct hh_cache *hh = dst->hh; 170 struct net_device *dev = dst->dev; 171 int hh_len = LL_RESERVED_SPACE(dev); 172 173 /* Be paranoid, rather than too clever. */ 174 if (unlikely(skb_headroom(skb) < hh_len && dev->hard_header)) { 175 struct sk_buff *skb2; 176 177 skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev)); 178 if (skb2 == NULL) { 179 kfree_skb(skb); 180 return -ENOMEM; 181 } 182 if (skb->sk) 183 skb_set_owner_w(skb2, skb->sk); 184 kfree_skb(skb); 185 skb = skb2; 186 } 187 188 if (hh) { 189 int hh_alen; 190 191 read_lock_bh(&hh->hh_lock); 192 hh_alen = HH_DATA_ALIGN(hh->hh_len); 193 memcpy(skb->data - hh_alen, hh->hh_data, hh_alen); 194 read_unlock_bh(&hh->hh_lock); 195 skb_push(skb, hh->hh_len); 196 return hh->hh_output(skb); 197 } else if (dst->neighbour) 198 return dst->neighbour->output(skb); 199 200 if (net_ratelimit()) 201 printk(KERN_DEBUG "ip_finish_output2: No header cache and no neighbour!\n"); 202 kfree_skb(skb); 203 return -EINVAL; 204 } 205 206 static inline int ip_finish_output(struct sk_buff *skb) 207 { 208 #if defined(CONFIG_NETFILTER) && defined(CONFIG_XFRM) 209 /* Policy lookup after SNAT yielded a new policy */ 210 if (skb->dst->xfrm != NULL) 211 return xfrm4_output_finish(skb); 212 #endif 213 if (skb->len > dst_mtu(skb->dst) && 214 !(skb_shinfo(skb)->ufo_size || skb_shinfo(skb)->tso_size)) 215 return ip_fragment(skb, ip_finish_output2); 216 else 217 return ip_finish_output2(skb); 218 } 219 220 int ip_mc_output(struct sk_buff *skb) 221 { 222 struct sock *sk = skb->sk; 223 struct rtable *rt = (struct rtable*)skb->dst; 224 struct net_device *dev = rt->u.dst.dev; 225 226 /* 227 * If the indicated interface is up and running, send the packet. 228 */ 229 IP_INC_STATS(IPSTATS_MIB_OUTREQUESTS); 230 231 skb->dev = dev; 232 skb->protocol = htons(ETH_P_IP); 233 234 /* 235 * Multicasts are looped back for other local users 236 */ 237 238 if (rt->rt_flags&RTCF_MULTICAST) { 239 if ((!sk || inet_sk(sk)->mc_loop) 240 #ifdef CONFIG_IP_MROUTE 241 /* Small optimization: do not loopback not local frames, 242 which returned after forwarding; they will be dropped 243 by ip_mr_input in any case. 244 Note, that local frames are looped back to be delivered 245 to local recipients. 246 247 This check is duplicated in ip_mr_input at the moment. 248 */ 249 && ((rt->rt_flags&RTCF_LOCAL) || !(IPCB(skb)->flags&IPSKB_FORWARDED)) 250 #endif 251 ) { 252 struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); 253 if (newskb) 254 NF_HOOK(PF_INET, NF_IP_POST_ROUTING, newskb, NULL, 255 newskb->dev, 256 ip_dev_loopback_xmit); 257 } 258 259 /* Multicasts with ttl 0 must not go beyond the host */ 260 261 if (skb->nh.iph->ttl == 0) { 262 kfree_skb(skb); 263 return 0; 264 } 265 } 266 267 if (rt->rt_flags&RTCF_BROADCAST) { 268 struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC); 269 if (newskb) 270 NF_HOOK(PF_INET, NF_IP_POST_ROUTING, newskb, NULL, 271 newskb->dev, ip_dev_loopback_xmit); 272 } 273 274 return NF_HOOK(PF_INET, NF_IP_POST_ROUTING, skb, NULL, skb->dev, 275 ip_finish_output); 276 } 277 278 int ip_output(struct sk_buff *skb) 279 { 280 struct net_device *dev = skb->dst->dev; 281 282 IP_INC_STATS(IPSTATS_MIB_OUTREQUESTS); 283 284 skb->dev = dev; 285 skb->protocol = htons(ETH_P_IP); 286 287 return NF_HOOK(PF_INET, NF_IP_POST_ROUTING, skb, NULL, dev, 288 ip_finish_output); 289 } 290 291 int ip_queue_xmit(struct sk_buff *skb, int ipfragok) 292 { 293 struct sock *sk = skb->sk; 294 struct inet_sock *inet = inet_sk(sk); 295 struct ip_options *opt = inet->opt; 296 struct rtable *rt; 297 struct iphdr *iph; 298 299 /* Skip all of this if the packet is already routed, 300 * f.e. by something like SCTP. 301 */ 302 rt = (struct rtable *) skb->dst; 303 if (rt != NULL) 304 goto packet_routed; 305 306 /* Make sure we can route this packet. */ 307 rt = (struct rtable *)__sk_dst_check(sk, 0); 308 if (rt == NULL) { 309 u32 daddr; 310 311 /* Use correct destination address if we have options. */ 312 daddr = inet->daddr; 313 if(opt && opt->srr) 314 daddr = opt->faddr; 315 316 { 317 struct flowi fl = { .oif = sk->sk_bound_dev_if, 318 .nl_u = { .ip4_u = 319 { .daddr = daddr, 320 .saddr = inet->saddr, 321 .tos = RT_CONN_FLAGS(sk) } }, 322 .proto = sk->sk_protocol, 323 .uli_u = { .ports = 324 { .sport = inet->sport, 325 .dport = inet->dport } } }; 326 327 /* If this fails, retransmit mechanism of transport layer will 328 * keep trying until route appears or the connection times 329 * itself out. 330 */ 331 if (ip_route_output_flow(&rt, &fl, sk, 0)) 332 goto no_route; 333 } 334 sk_setup_caps(sk, &rt->u.dst); 335 } 336 skb->dst = dst_clone(&rt->u.dst); 337 338 packet_routed: 339 if (opt && opt->is_strictroute && rt->rt_dst != rt->rt_gateway) 340 goto no_route; 341 342 /* OK, we know where to send it, allocate and build IP header. */ 343 iph = (struct iphdr *) skb_push(skb, sizeof(struct iphdr) + (opt ? opt->optlen : 0)); 344 *((__u16 *)iph) = htons((4 << 12) | (5 << 8) | (inet->tos & 0xff)); 345 iph->tot_len = htons(skb->len); 346 if (ip_dont_fragment(sk, &rt->u.dst) && !ipfragok) 347 iph->frag_off = htons(IP_DF); 348 else 349 iph->frag_off = 0; 350 iph->ttl = ip_select_ttl(inet, &rt->u.dst); 351 iph->protocol = sk->sk_protocol; 352 iph->saddr = rt->rt_src; 353 iph->daddr = rt->rt_dst; 354 skb->nh.iph = iph; 355 /* Transport layer set skb->h.foo itself. */ 356 357 if (opt && opt->optlen) { 358 iph->ihl += opt->optlen >> 2; 359 ip_options_build(skb, opt, inet->daddr, rt, 0); 360 } 361 362 ip_select_ident_more(iph, &rt->u.dst, sk, 363 (skb_shinfo(skb)->tso_segs ?: 1) - 1); 364 365 /* Add an IP checksum. */ 366 ip_send_check(iph); 367 368 skb->priority = sk->sk_priority; 369 370 return NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, rt->u.dst.dev, 371 dst_output); 372 373 no_route: 374 IP_INC_STATS(IPSTATS_MIB_OUTNOROUTES); 375 kfree_skb(skb); 376 return -EHOSTUNREACH; 377 } 378 379 380 static void ip_copy_metadata(struct sk_buff *to, struct sk_buff *from) 381 { 382 to->pkt_type = from->pkt_type; 383 to->priority = from->priority; 384 to->protocol = from->protocol; 385 dst_release(to->dst); 386 to->dst = dst_clone(from->dst); 387 to->dev = from->dev; 388 389 /* Copy the flags to each fragment. */ 390 IPCB(to)->flags = IPCB(from)->flags; 391 392 #ifdef CONFIG_NET_SCHED 393 to->tc_index = from->tc_index; 394 #endif 395 #ifdef CONFIG_NETFILTER 396 to->nfmark = from->nfmark; 397 /* Connection association is same as pre-frag packet */ 398 nf_conntrack_put(to->nfct); 399 to->nfct = from->nfct; 400 nf_conntrack_get(to->nfct); 401 to->nfctinfo = from->nfctinfo; 402 #if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE) 403 to->ipvs_property = from->ipvs_property; 404 #endif 405 #ifdef CONFIG_BRIDGE_NETFILTER 406 nf_bridge_put(to->nf_bridge); 407 to->nf_bridge = from->nf_bridge; 408 nf_bridge_get(to->nf_bridge); 409 #endif 410 #endif 411 } 412 413 /* 414 * This IP datagram is too large to be sent in one piece. Break it up into 415 * smaller pieces (each of size equal to IP header plus 416 * a block of the data of the original IP data part) that will yet fit in a 417 * single device frame, and queue such a frame for sending. 418 */ 419 420 static int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff*)) 421 { 422 struct iphdr *iph; 423 int raw = 0; 424 int ptr; 425 struct net_device *dev; 426 struct sk_buff *skb2; 427 unsigned int mtu, hlen, left, len, ll_rs; 428 int offset; 429 __be16 not_last_frag; 430 struct rtable *rt = (struct rtable*)skb->dst; 431 int err = 0; 432 433 dev = rt->u.dst.dev; 434 435 /* 436 * Point into the IP datagram header. 437 */ 438 439 iph = skb->nh.iph; 440 441 if (unlikely((iph->frag_off & htons(IP_DF)) && !skb->local_df)) { 442 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, 443 htonl(dst_mtu(&rt->u.dst))); 444 kfree_skb(skb); 445 return -EMSGSIZE; 446 } 447 448 /* 449 * Setup starting values. 450 */ 451 452 hlen = iph->ihl * 4; 453 mtu = dst_mtu(&rt->u.dst) - hlen; /* Size of data space */ 454 IPCB(skb)->flags |= IPSKB_FRAG_COMPLETE; 455 456 /* When frag_list is given, use it. First, check its validity: 457 * some transformers could create wrong frag_list or break existing 458 * one, it is not prohibited. In this case fall back to copying. 459 * 460 * LATER: this step can be merged to real generation of fragments, 461 * we can switch to copy when see the first bad fragment. 462 */ 463 if (skb_shinfo(skb)->frag_list) { 464 struct sk_buff *frag; 465 int first_len = skb_pagelen(skb); 466 467 if (first_len - hlen > mtu || 468 ((first_len - hlen) & 7) || 469 (iph->frag_off & htons(IP_MF|IP_OFFSET)) || 470 skb_cloned(skb)) 471 goto slow_path; 472 473 for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next) { 474 /* Correct geometry. */ 475 if (frag->len > mtu || 476 ((frag->len & 7) && frag->next) || 477 skb_headroom(frag) < hlen) 478 goto slow_path; 479 480 /* Partially cloned skb? */ 481 if (skb_shared(frag)) 482 goto slow_path; 483 484 BUG_ON(frag->sk); 485 if (skb->sk) { 486 sock_hold(skb->sk); 487 frag->sk = skb->sk; 488 frag->destructor = sock_wfree; 489 skb->truesize -= frag->truesize; 490 } 491 } 492 493 /* Everything is OK. Generate! */ 494 495 err = 0; 496 offset = 0; 497 frag = skb_shinfo(skb)->frag_list; 498 skb_shinfo(skb)->frag_list = NULL; 499 skb->data_len = first_len - skb_headlen(skb); 500 skb->len = first_len; 501 iph->tot_len = htons(first_len); 502 iph->frag_off = htons(IP_MF); 503 ip_send_check(iph); 504 505 for (;;) { 506 /* Prepare header of the next frame, 507 * before previous one went down. */ 508 if (frag) { 509 frag->ip_summed = CHECKSUM_NONE; 510 frag->h.raw = frag->data; 511 frag->nh.raw = __skb_push(frag, hlen); 512 memcpy(frag->nh.raw, iph, hlen); 513 iph = frag->nh.iph; 514 iph->tot_len = htons(frag->len); 515 ip_copy_metadata(frag, skb); 516 if (offset == 0) 517 ip_options_fragment(frag); 518 offset += skb->len - hlen; 519 iph->frag_off = htons(offset>>3); 520 if (frag->next != NULL) 521 iph->frag_off |= htons(IP_MF); 522 /* Ready, complete checksum */ 523 ip_send_check(iph); 524 } 525 526 err = output(skb); 527 528 if (err || !frag) 529 break; 530 531 skb = frag; 532 frag = skb->next; 533 skb->next = NULL; 534 } 535 536 if (err == 0) { 537 IP_INC_STATS(IPSTATS_MIB_FRAGOKS); 538 return 0; 539 } 540 541 while (frag) { 542 skb = frag->next; 543 kfree_skb(frag); 544 frag = skb; 545 } 546 IP_INC_STATS(IPSTATS_MIB_FRAGFAILS); 547 return err; 548 } 549 550 slow_path: 551 left = skb->len - hlen; /* Space per frame */ 552 ptr = raw + hlen; /* Where to start from */ 553 554 #ifdef CONFIG_BRIDGE_NETFILTER 555 /* for bridged IP traffic encapsulated inside f.e. a vlan header, 556 * we need to make room for the encapsulating header */ 557 ll_rs = LL_RESERVED_SPACE_EXTRA(rt->u.dst.dev, nf_bridge_pad(skb)); 558 mtu -= nf_bridge_pad(skb); 559 #else 560 ll_rs = LL_RESERVED_SPACE(rt->u.dst.dev); 561 #endif 562 /* 563 * Fragment the datagram. 564 */ 565 566 offset = (ntohs(iph->frag_off) & IP_OFFSET) << 3; 567 not_last_frag = iph->frag_off & htons(IP_MF); 568 569 /* 570 * Keep copying data until we run out. 571 */ 572 573 while(left > 0) { 574 len = left; 575 /* IF: it doesn't fit, use 'mtu' - the data space left */ 576 if (len > mtu) 577 len = mtu; 578 /* IF: we are not sending upto and including the packet end 579 then align the next start on an eight byte boundary */ 580 if (len < left) { 581 len &= ~7; 582 } 583 /* 584 * Allocate buffer. 585 */ 586 587 if ((skb2 = alloc_skb(len+hlen+ll_rs, GFP_ATOMIC)) == NULL) { 588 NETDEBUG(KERN_INFO "IP: frag: no memory for new fragment!\n"); 589 err = -ENOMEM; 590 goto fail; 591 } 592 593 /* 594 * Set up data on packet 595 */ 596 597 ip_copy_metadata(skb2, skb); 598 skb_reserve(skb2, ll_rs); 599 skb_put(skb2, len + hlen); 600 skb2->nh.raw = skb2->data; 601 skb2->h.raw = skb2->data + hlen; 602 603 /* 604 * Charge the memory for the fragment to any owner 605 * it might possess 606 */ 607 608 if (skb->sk) 609 skb_set_owner_w(skb2, skb->sk); 610 611 /* 612 * Copy the packet header into the new buffer. 613 */ 614 615 memcpy(skb2->nh.raw, skb->data, hlen); 616 617 /* 618 * Copy a block of the IP datagram. 619 */ 620 if (skb_copy_bits(skb, ptr, skb2->h.raw, len)) 621 BUG(); 622 left -= len; 623 624 /* 625 * Fill in the new header fields. 626 */ 627 iph = skb2->nh.iph; 628 iph->frag_off = htons((offset >> 3)); 629 630 /* ANK: dirty, but effective trick. Upgrade options only if 631 * the segment to be fragmented was THE FIRST (otherwise, 632 * options are already fixed) and make it ONCE 633 * on the initial skb, so that all the following fragments 634 * will inherit fixed options. 635 */ 636 if (offset == 0) 637 ip_options_fragment(skb); 638 639 /* 640 * Added AC : If we are fragmenting a fragment that's not the 641 * last fragment then keep MF on each bit 642 */ 643 if (left > 0 || not_last_frag) 644 iph->frag_off |= htons(IP_MF); 645 ptr += len; 646 offset += len; 647 648 /* 649 * Put this fragment into the sending queue. 650 */ 651 652 IP_INC_STATS(IPSTATS_MIB_FRAGCREATES); 653 654 iph->tot_len = htons(len + hlen); 655 656 ip_send_check(iph); 657 658 err = output(skb2); 659 if (err) 660 goto fail; 661 } 662 kfree_skb(skb); 663 IP_INC_STATS(IPSTATS_MIB_FRAGOKS); 664 return err; 665 666 fail: 667 kfree_skb(skb); 668 IP_INC_STATS(IPSTATS_MIB_FRAGFAILS); 669 return err; 670 } 671 672 int 673 ip_generic_getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb) 674 { 675 struct iovec *iov = from; 676 677 if (skb->ip_summed == CHECKSUM_HW) { 678 if (memcpy_fromiovecend(to, iov, offset, len) < 0) 679 return -EFAULT; 680 } else { 681 unsigned int csum = 0; 682 if (csum_partial_copy_fromiovecend(to, iov, offset, len, &csum) < 0) 683 return -EFAULT; 684 skb->csum = csum_block_add(skb->csum, csum, odd); 685 } 686 return 0; 687 } 688 689 static inline unsigned int 690 csum_page(struct page *page, int offset, int copy) 691 { 692 char *kaddr; 693 unsigned int csum; 694 kaddr = kmap(page); 695 csum = csum_partial(kaddr + offset, copy, 0); 696 kunmap(page); 697 return csum; 698 } 699 700 static inline int ip_ufo_append_data(struct sock *sk, 701 int getfrag(void *from, char *to, int offset, int len, 702 int odd, struct sk_buff *skb), 703 void *from, int length, int hh_len, int fragheaderlen, 704 int transhdrlen, int mtu,unsigned int flags) 705 { 706 struct sk_buff *skb; 707 int err; 708 709 /* There is support for UDP fragmentation offload by network 710 * device, so create one single skb packet containing complete 711 * udp datagram 712 */ 713 if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) { 714 skb = sock_alloc_send_skb(sk, 715 hh_len + fragheaderlen + transhdrlen + 20, 716 (flags & MSG_DONTWAIT), &err); 717 718 if (skb == NULL) 719 return err; 720 721 /* reserve space for Hardware header */ 722 skb_reserve(skb, hh_len); 723 724 /* create space for UDP/IP header */ 725 skb_put(skb,fragheaderlen + transhdrlen); 726 727 /* initialize network header pointer */ 728 skb->nh.raw = skb->data; 729 730 /* initialize protocol header pointer */ 731 skb->h.raw = skb->data + fragheaderlen; 732 733 skb->ip_summed = CHECKSUM_HW; 734 skb->csum = 0; 735 sk->sk_sndmsg_off = 0; 736 } 737 738 err = skb_append_datato_frags(sk,skb, getfrag, from, 739 (length - transhdrlen)); 740 if (!err) { 741 /* specify the length of each IP datagram fragment*/ 742 skb_shinfo(skb)->ufo_size = (mtu - fragheaderlen); 743 __skb_queue_tail(&sk->sk_write_queue, skb); 744 745 return 0; 746 } 747 /* There is not enough support do UFO , 748 * so follow normal path 749 */ 750 kfree_skb(skb); 751 return err; 752 } 753 754 /* 755 * ip_append_data() and ip_append_page() can make one large IP datagram 756 * from many pieces of data. Each pieces will be holded on the socket 757 * until ip_push_pending_frames() is called. Each piece can be a page 758 * or non-page data. 759 * 760 * Not only UDP, other transport protocols - e.g. raw sockets - can use 761 * this interface potentially. 762 * 763 * LATER: length must be adjusted by pad at tail, when it is required. 764 */ 765 int ip_append_data(struct sock *sk, 766 int getfrag(void *from, char *to, int offset, int len, 767 int odd, struct sk_buff *skb), 768 void *from, int length, int transhdrlen, 769 struct ipcm_cookie *ipc, struct rtable *rt, 770 unsigned int flags) 771 { 772 struct inet_sock *inet = inet_sk(sk); 773 struct sk_buff *skb; 774 775 struct ip_options *opt = NULL; 776 int hh_len; 777 int exthdrlen; 778 int mtu; 779 int copy; 780 int err; 781 int offset = 0; 782 unsigned int maxfraglen, fragheaderlen; 783 int csummode = CHECKSUM_NONE; 784 785 if (flags&MSG_PROBE) 786 return 0; 787 788 if (skb_queue_empty(&sk->sk_write_queue)) { 789 /* 790 * setup for corking. 791 */ 792 opt = ipc->opt; 793 if (opt) { 794 if (inet->cork.opt == NULL) { 795 inet->cork.opt = kmalloc(sizeof(struct ip_options) + 40, sk->sk_allocation); 796 if (unlikely(inet->cork.opt == NULL)) 797 return -ENOBUFS; 798 } 799 memcpy(inet->cork.opt, opt, sizeof(struct ip_options)+opt->optlen); 800 inet->cork.flags |= IPCORK_OPT; 801 inet->cork.addr = ipc->addr; 802 } 803 dst_hold(&rt->u.dst); 804 inet->cork.fragsize = mtu = dst_mtu(rt->u.dst.path); 805 inet->cork.rt = rt; 806 inet->cork.length = 0; 807 sk->sk_sndmsg_page = NULL; 808 sk->sk_sndmsg_off = 0; 809 if ((exthdrlen = rt->u.dst.header_len) != 0) { 810 length += exthdrlen; 811 transhdrlen += exthdrlen; 812 } 813 } else { 814 rt = inet->cork.rt; 815 if (inet->cork.flags & IPCORK_OPT) 816 opt = inet->cork.opt; 817 818 transhdrlen = 0; 819 exthdrlen = 0; 820 mtu = inet->cork.fragsize; 821 } 822 hh_len = LL_RESERVED_SPACE(rt->u.dst.dev); 823 824 fragheaderlen = sizeof(struct iphdr) + (opt ? opt->optlen : 0); 825 maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen; 826 827 if (inet->cork.length + length > 0xFFFF - fragheaderlen) { 828 ip_local_error(sk, EMSGSIZE, rt->rt_dst, inet->dport, mtu-exthdrlen); 829 return -EMSGSIZE; 830 } 831 832 /* 833 * transhdrlen > 0 means that this is the first fragment and we wish 834 * it won't be fragmented in the future. 835 */ 836 if (transhdrlen && 837 length + fragheaderlen <= mtu && 838 rt->u.dst.dev->features&(NETIF_F_IP_CSUM|NETIF_F_NO_CSUM|NETIF_F_HW_CSUM) && 839 !exthdrlen) 840 csummode = CHECKSUM_HW; 841 842 inet->cork.length += length; 843 if (((length > mtu) && (sk->sk_protocol == IPPROTO_UDP)) && 844 (rt->u.dst.dev->features & NETIF_F_UFO)) { 845 846 if(ip_ufo_append_data(sk, getfrag, from, length, hh_len, 847 fragheaderlen, transhdrlen, mtu, flags)) 848 goto error; 849 850 return 0; 851 } 852 853 /* So, what's going on in the loop below? 854 * 855 * We use calculated fragment length to generate chained skb, 856 * each of segments is IP fragment ready for sending to network after 857 * adding appropriate IP header. 858 */ 859 860 if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) 861 goto alloc_new_skb; 862 863 while (length > 0) { 864 /* Check if the remaining data fits into current packet. */ 865 copy = mtu - skb->len; 866 if (copy < length) 867 copy = maxfraglen - skb->len; 868 if (copy <= 0) { 869 char *data; 870 unsigned int datalen; 871 unsigned int fraglen; 872 unsigned int fraggap; 873 unsigned int alloclen; 874 struct sk_buff *skb_prev; 875 alloc_new_skb: 876 skb_prev = skb; 877 if (skb_prev) 878 fraggap = skb_prev->len - maxfraglen; 879 else 880 fraggap = 0; 881 882 /* 883 * If remaining data exceeds the mtu, 884 * we know we need more fragment(s). 885 */ 886 datalen = length + fraggap; 887 if (datalen > mtu - fragheaderlen) 888 datalen = maxfraglen - fragheaderlen; 889 fraglen = datalen + fragheaderlen; 890 891 if ((flags & MSG_MORE) && 892 !(rt->u.dst.dev->features&NETIF_F_SG)) 893 alloclen = mtu; 894 else 895 alloclen = datalen + fragheaderlen; 896 897 /* The last fragment gets additional space at tail. 898 * Note, with MSG_MORE we overallocate on fragments, 899 * because we have no idea what fragment will be 900 * the last. 901 */ 902 if (datalen == length) 903 alloclen += rt->u.dst.trailer_len; 904 905 if (transhdrlen) { 906 skb = sock_alloc_send_skb(sk, 907 alloclen + hh_len + 15, 908 (flags & MSG_DONTWAIT), &err); 909 } else { 910 skb = NULL; 911 if (atomic_read(&sk->sk_wmem_alloc) <= 912 2 * sk->sk_sndbuf) 913 skb = sock_wmalloc(sk, 914 alloclen + hh_len + 15, 1, 915 sk->sk_allocation); 916 if (unlikely(skb == NULL)) 917 err = -ENOBUFS; 918 } 919 if (skb == NULL) 920 goto error; 921 922 /* 923 * Fill in the control structures 924 */ 925 skb->ip_summed = csummode; 926 skb->csum = 0; 927 skb_reserve(skb, hh_len); 928 929 /* 930 * Find where to start putting bytes. 931 */ 932 data = skb_put(skb, fraglen); 933 skb->nh.raw = data + exthdrlen; 934 data += fragheaderlen; 935 skb->h.raw = data + exthdrlen; 936 937 if (fraggap) { 938 skb->csum = skb_copy_and_csum_bits( 939 skb_prev, maxfraglen, 940 data + transhdrlen, fraggap, 0); 941 skb_prev->csum = csum_sub(skb_prev->csum, 942 skb->csum); 943 data += fraggap; 944 skb_trim(skb_prev, maxfraglen); 945 } 946 947 copy = datalen - transhdrlen - fraggap; 948 if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) { 949 err = -EFAULT; 950 kfree_skb(skb); 951 goto error; 952 } 953 954 offset += copy; 955 length -= datalen - fraggap; 956 transhdrlen = 0; 957 exthdrlen = 0; 958 csummode = CHECKSUM_NONE; 959 960 /* 961 * Put the packet on the pending queue. 962 */ 963 __skb_queue_tail(&sk->sk_write_queue, skb); 964 continue; 965 } 966 967 if (copy > length) 968 copy = length; 969 970 if (!(rt->u.dst.dev->features&NETIF_F_SG)) { 971 unsigned int off; 972 973 off = skb->len; 974 if (getfrag(from, skb_put(skb, copy), 975 offset, copy, off, skb) < 0) { 976 __skb_trim(skb, off); 977 err = -EFAULT; 978 goto error; 979 } 980 } else { 981 int i = skb_shinfo(skb)->nr_frags; 982 skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1]; 983 struct page *page = sk->sk_sndmsg_page; 984 int off = sk->sk_sndmsg_off; 985 unsigned int left; 986 987 if (page && (left = PAGE_SIZE - off) > 0) { 988 if (copy >= left) 989 copy = left; 990 if (page != frag->page) { 991 if (i == MAX_SKB_FRAGS) { 992 err = -EMSGSIZE; 993 goto error; 994 } 995 get_page(page); 996 skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0); 997 frag = &skb_shinfo(skb)->frags[i]; 998 } 999 } else if (i < MAX_SKB_FRAGS) { 1000 if (copy > PAGE_SIZE) 1001 copy = PAGE_SIZE; 1002 page = alloc_pages(sk->sk_allocation, 0); 1003 if (page == NULL) { 1004 err = -ENOMEM; 1005 goto error; 1006 } 1007 sk->sk_sndmsg_page = page; 1008 sk->sk_sndmsg_off = 0; 1009 1010 skb_fill_page_desc(skb, i, page, 0, 0); 1011 frag = &skb_shinfo(skb)->frags[i]; 1012 skb->truesize += PAGE_SIZE; 1013 atomic_add(PAGE_SIZE, &sk->sk_wmem_alloc); 1014 } else { 1015 err = -EMSGSIZE; 1016 goto error; 1017 } 1018 if (getfrag(from, page_address(frag->page)+frag->page_offset+frag->size, offset, copy, skb->len, skb) < 0) { 1019 err = -EFAULT; 1020 goto error; 1021 } 1022 sk->sk_sndmsg_off += copy; 1023 frag->size += copy; 1024 skb->len += copy; 1025 skb->data_len += copy; 1026 } 1027 offset += copy; 1028 length -= copy; 1029 } 1030 1031 return 0; 1032 1033 error: 1034 inet->cork.length -= length; 1035 IP_INC_STATS(IPSTATS_MIB_OUTDISCARDS); 1036 return err; 1037 } 1038 1039 ssize_t ip_append_page(struct sock *sk, struct page *page, 1040 int offset, size_t size, int flags) 1041 { 1042 struct inet_sock *inet = inet_sk(sk); 1043 struct sk_buff *skb; 1044 struct rtable *rt; 1045 struct ip_options *opt = NULL; 1046 int hh_len; 1047 int mtu; 1048 int len; 1049 int err; 1050 unsigned int maxfraglen, fragheaderlen, fraggap; 1051 1052 if (inet->hdrincl) 1053 return -EPERM; 1054 1055 if (flags&MSG_PROBE) 1056 return 0; 1057 1058 if (skb_queue_empty(&sk->sk_write_queue)) 1059 return -EINVAL; 1060 1061 rt = inet->cork.rt; 1062 if (inet->cork.flags & IPCORK_OPT) 1063 opt = inet->cork.opt; 1064 1065 if (!(rt->u.dst.dev->features&NETIF_F_SG)) 1066 return -EOPNOTSUPP; 1067 1068 hh_len = LL_RESERVED_SPACE(rt->u.dst.dev); 1069 mtu = inet->cork.fragsize; 1070 1071 fragheaderlen = sizeof(struct iphdr) + (opt ? opt->optlen : 0); 1072 maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen; 1073 1074 if (inet->cork.length + size > 0xFFFF - fragheaderlen) { 1075 ip_local_error(sk, EMSGSIZE, rt->rt_dst, inet->dport, mtu); 1076 return -EMSGSIZE; 1077 } 1078 1079 if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) 1080 return -EINVAL; 1081 1082 inet->cork.length += size; 1083 if ((sk->sk_protocol == IPPROTO_UDP) && 1084 (rt->u.dst.dev->features & NETIF_F_UFO)) 1085 skb_shinfo(skb)->ufo_size = (mtu - fragheaderlen); 1086 1087 1088 while (size > 0) { 1089 int i; 1090 1091 if (skb_shinfo(skb)->ufo_size) 1092 len = size; 1093 else { 1094 1095 /* Check if the remaining data fits into current packet. */ 1096 len = mtu - skb->len; 1097 if (len < size) 1098 len = maxfraglen - skb->len; 1099 } 1100 if (len <= 0) { 1101 struct sk_buff *skb_prev; 1102 char *data; 1103 struct iphdr *iph; 1104 int alloclen; 1105 1106 skb_prev = skb; 1107 fraggap = skb_prev->len - maxfraglen; 1108 1109 alloclen = fragheaderlen + hh_len + fraggap + 15; 1110 skb = sock_wmalloc(sk, alloclen, 1, sk->sk_allocation); 1111 if (unlikely(!skb)) { 1112 err = -ENOBUFS; 1113 goto error; 1114 } 1115 1116 /* 1117 * Fill in the control structures 1118 */ 1119 skb->ip_summed = CHECKSUM_NONE; 1120 skb->csum = 0; 1121 skb_reserve(skb, hh_len); 1122 1123 /* 1124 * Find where to start putting bytes. 1125 */ 1126 data = skb_put(skb, fragheaderlen + fraggap); 1127 skb->nh.iph = iph = (struct iphdr *)data; 1128 data += fragheaderlen; 1129 skb->h.raw = data; 1130 1131 if (fraggap) { 1132 skb->csum = skb_copy_and_csum_bits( 1133 skb_prev, maxfraglen, 1134 data, fraggap, 0); 1135 skb_prev->csum = csum_sub(skb_prev->csum, 1136 skb->csum); 1137 skb_trim(skb_prev, maxfraglen); 1138 } 1139 1140 /* 1141 * Put the packet on the pending queue. 1142 */ 1143 __skb_queue_tail(&sk->sk_write_queue, skb); 1144 continue; 1145 } 1146 1147 i = skb_shinfo(skb)->nr_frags; 1148 if (len > size) 1149 len = size; 1150 if (skb_can_coalesce(skb, i, page, offset)) { 1151 skb_shinfo(skb)->frags[i-1].size += len; 1152 } else if (i < MAX_SKB_FRAGS) { 1153 get_page(page); 1154 skb_fill_page_desc(skb, i, page, offset, len); 1155 } else { 1156 err = -EMSGSIZE; 1157 goto error; 1158 } 1159 1160 if (skb->ip_summed == CHECKSUM_NONE) { 1161 unsigned int csum; 1162 csum = csum_page(page, offset, len); 1163 skb->csum = csum_block_add(skb->csum, csum, skb->len); 1164 } 1165 1166 skb->len += len; 1167 skb->data_len += len; 1168 offset += len; 1169 size -= len; 1170 } 1171 return 0; 1172 1173 error: 1174 inet->cork.length -= size; 1175 IP_INC_STATS(IPSTATS_MIB_OUTDISCARDS); 1176 return err; 1177 } 1178 1179 /* 1180 * Combined all pending IP fragments on the socket as one IP datagram 1181 * and push them out. 1182 */ 1183 int ip_push_pending_frames(struct sock *sk) 1184 { 1185 struct sk_buff *skb, *tmp_skb; 1186 struct sk_buff **tail_skb; 1187 struct inet_sock *inet = inet_sk(sk); 1188 struct ip_options *opt = NULL; 1189 struct rtable *rt = inet->cork.rt; 1190 struct iphdr *iph; 1191 __be16 df = 0; 1192 __u8 ttl; 1193 int err = 0; 1194 1195 if ((skb = __skb_dequeue(&sk->sk_write_queue)) == NULL) 1196 goto out; 1197 tail_skb = &(skb_shinfo(skb)->frag_list); 1198 1199 /* move skb->data to ip header from ext header */ 1200 if (skb->data < skb->nh.raw) 1201 __skb_pull(skb, skb->nh.raw - skb->data); 1202 while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) { 1203 __skb_pull(tmp_skb, skb->h.raw - skb->nh.raw); 1204 *tail_skb = tmp_skb; 1205 tail_skb = &(tmp_skb->next); 1206 skb->len += tmp_skb->len; 1207 skb->data_len += tmp_skb->len; 1208 skb->truesize += tmp_skb->truesize; 1209 __sock_put(tmp_skb->sk); 1210 tmp_skb->destructor = NULL; 1211 tmp_skb->sk = NULL; 1212 } 1213 1214 /* Unless user demanded real pmtu discovery (IP_PMTUDISC_DO), we allow 1215 * to fragment the frame generated here. No matter, what transforms 1216 * how transforms change size of the packet, it will come out. 1217 */ 1218 if (inet->pmtudisc != IP_PMTUDISC_DO) 1219 skb->local_df = 1; 1220 1221 /* DF bit is set when we want to see DF on outgoing frames. 1222 * If local_df is set too, we still allow to fragment this frame 1223 * locally. */ 1224 if (inet->pmtudisc == IP_PMTUDISC_DO || 1225 (skb->len <= dst_mtu(&rt->u.dst) && 1226 ip_dont_fragment(sk, &rt->u.dst))) 1227 df = htons(IP_DF); 1228 1229 if (inet->cork.flags & IPCORK_OPT) 1230 opt = inet->cork.opt; 1231 1232 if (rt->rt_type == RTN_MULTICAST) 1233 ttl = inet->mc_ttl; 1234 else 1235 ttl = ip_select_ttl(inet, &rt->u.dst); 1236 1237 iph = (struct iphdr *)skb->data; 1238 iph->version = 4; 1239 iph->ihl = 5; 1240 if (opt) { 1241 iph->ihl += opt->optlen>>2; 1242 ip_options_build(skb, opt, inet->cork.addr, rt, 0); 1243 } 1244 iph->tos = inet->tos; 1245 iph->tot_len = htons(skb->len); 1246 iph->frag_off = df; 1247 if (!df) { 1248 __ip_select_ident(iph, &rt->u.dst, 0); 1249 } else { 1250 iph->id = htons(inet->id++); 1251 } 1252 iph->ttl = ttl; 1253 iph->protocol = sk->sk_protocol; 1254 iph->saddr = rt->rt_src; 1255 iph->daddr = rt->rt_dst; 1256 ip_send_check(iph); 1257 1258 skb->priority = sk->sk_priority; 1259 skb->dst = dst_clone(&rt->u.dst); 1260 1261 /* Netfilter gets whole the not fragmented skb. */ 1262 err = NF_HOOK(PF_INET, NF_IP_LOCAL_OUT, skb, NULL, 1263 skb->dst->dev, dst_output); 1264 if (err) { 1265 if (err > 0) 1266 err = inet->recverr ? net_xmit_errno(err) : 0; 1267 if (err) 1268 goto error; 1269 } 1270 1271 out: 1272 inet->cork.flags &= ~IPCORK_OPT; 1273 kfree(inet->cork.opt); 1274 inet->cork.opt = NULL; 1275 if (inet->cork.rt) { 1276 ip_rt_put(inet->cork.rt); 1277 inet->cork.rt = NULL; 1278 } 1279 return err; 1280 1281 error: 1282 IP_INC_STATS(IPSTATS_MIB_OUTDISCARDS); 1283 goto out; 1284 } 1285 1286 /* 1287 * Throw away all pending data on the socket. 1288 */ 1289 void ip_flush_pending_frames(struct sock *sk) 1290 { 1291 struct inet_sock *inet = inet_sk(sk); 1292 struct sk_buff *skb; 1293 1294 while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) 1295 kfree_skb(skb); 1296 1297 inet->cork.flags &= ~IPCORK_OPT; 1298 kfree(inet->cork.opt); 1299 inet->cork.opt = NULL; 1300 if (inet->cork.rt) { 1301 ip_rt_put(inet->cork.rt); 1302 inet->cork.rt = NULL; 1303 } 1304 } 1305 1306 1307 /* 1308 * Fetch data from kernel space and fill in checksum if needed. 1309 */ 1310 static int ip_reply_glue_bits(void *dptr, char *to, int offset, 1311 int len, int odd, struct sk_buff *skb) 1312 { 1313 unsigned int csum; 1314 1315 csum = csum_partial_copy_nocheck(dptr+offset, to, len, 0); 1316 skb->csum = csum_block_add(skb->csum, csum, odd); 1317 return 0; 1318 } 1319 1320 /* 1321 * Generic function to send a packet as reply to another packet. 1322 * Used to send TCP resets so far. ICMP should use this function too. 1323 * 1324 * Should run single threaded per socket because it uses the sock 1325 * structure to pass arguments. 1326 * 1327 * LATER: switch from ip_build_xmit to ip_append_* 1328 */ 1329 void ip_send_reply(struct sock *sk, struct sk_buff *skb, struct ip_reply_arg *arg, 1330 unsigned int len) 1331 { 1332 struct inet_sock *inet = inet_sk(sk); 1333 struct { 1334 struct ip_options opt; 1335 char data[40]; 1336 } replyopts; 1337 struct ipcm_cookie ipc; 1338 u32 daddr; 1339 struct rtable *rt = (struct rtable*)skb->dst; 1340 1341 if (ip_options_echo(&replyopts.opt, skb)) 1342 return; 1343 1344 daddr = ipc.addr = rt->rt_src; 1345 ipc.opt = NULL; 1346 1347 if (replyopts.opt.optlen) { 1348 ipc.opt = &replyopts.opt; 1349 1350 if (ipc.opt->srr) 1351 daddr = replyopts.opt.faddr; 1352 } 1353 1354 { 1355 struct flowi fl = { .nl_u = { .ip4_u = 1356 { .daddr = daddr, 1357 .saddr = rt->rt_spec_dst, 1358 .tos = RT_TOS(skb->nh.iph->tos) } }, 1359 /* Not quite clean, but right. */ 1360 .uli_u = { .ports = 1361 { .sport = skb->h.th->dest, 1362 .dport = skb->h.th->source } }, 1363 .proto = sk->sk_protocol }; 1364 if (ip_route_output_key(&rt, &fl)) 1365 return; 1366 } 1367 1368 /* And let IP do all the hard work. 1369 1370 This chunk is not reenterable, hence spinlock. 1371 Note that it uses the fact, that this function is called 1372 with locally disabled BH and that sk cannot be already spinlocked. 1373 */ 1374 bh_lock_sock(sk); 1375 inet->tos = skb->nh.iph->tos; 1376 sk->sk_priority = skb->priority; 1377 sk->sk_protocol = skb->nh.iph->protocol; 1378 ip_append_data(sk, ip_reply_glue_bits, arg->iov->iov_base, len, 0, 1379 &ipc, rt, MSG_DONTWAIT); 1380 if ((skb = skb_peek(&sk->sk_write_queue)) != NULL) { 1381 if (arg->csumoffset >= 0) 1382 *((u16 *)skb->h.raw + arg->csumoffset) = csum_fold(csum_add(skb->csum, arg->csum)); 1383 skb->ip_summed = CHECKSUM_NONE; 1384 ip_push_pending_frames(sk); 1385 } 1386 1387 bh_unlock_sock(sk); 1388 1389 ip_rt_put(rt); 1390 } 1391 1392 void __init ip_init(void) 1393 { 1394 ip_rt_init(); 1395 inet_initpeers(); 1396 1397 #if defined(CONFIG_IP_MULTICAST) && defined(CONFIG_PROC_FS) 1398 igmp_mc_proc_init(); 1399 #endif 1400 } 1401 1402 EXPORT_SYMBOL(ip_generic_getfrag); 1403 EXPORT_SYMBOL(ip_queue_xmit); 1404 EXPORT_SYMBOL(ip_send_check); 1405