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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * IPv6 output functions
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +09003 * Linux INET6 implementation
Linus Torvalds1da177e2005-04-16 15:20:36 -07004 *
5 * Authors:
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +09006 * Pedro Roque <roque@di.fc.ul.pt>
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 * Based on linux/net/ipv4/ip_output.c
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * as published by the Free Software Foundation; either version
13 * 2 of the License, or (at your option) any later version.
14 *
15 * Changes:
16 * A.N.Kuznetsov : airthmetics in fragmentation.
17 * extension headers are implemented.
18 * route changes now work.
19 * ip6_forward does not confuse sniffers.
20 * etc.
21 *
22 * H. von Brand : Added missing #include <linux/string.h>
Ian Morris67ba4152014-08-24 21:53:10 +010023 * Imran Patel : frag id should be in NBO
Linus Torvalds1da177e2005-04-16 15:20:36 -070024 * Kazunori MIYAZAWA @USAGI
25 * : add ip6_append_data and related functions
26 * for datagram xmit
27 */
28
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#include <linux/errno.h>
Herbert Xuef76bc22008-01-11 19:15:08 -080030#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031#include <linux/string.h>
32#include <linux/socket.h>
33#include <linux/net.h>
34#include <linux/netdevice.h>
35#include <linux/if_arp.h>
36#include <linux/in6.h>
37#include <linux/tcp.h>
38#include <linux/route.h>
Herbert Xub59f45d2006-05-27 23:05:54 -070039#include <linux/module.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090040#include <linux/slab.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070041
Daniel Mack9290d742016-11-23 16:52:29 +010042#include <linux/bpf-cgroup.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070043#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>
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +090058#include <linux/mroute6.h>
David Ahernca254492015-10-12 11:47:10 -070059#include <net/l3mdev.h>
Roopa Prabhu14972cb2016-08-24 20:10:43 -070060#include <net/lwtunnel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070061
Eric W. Biederman7d8c6e32015-06-12 22:12:04 -050062static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -070063{
Eric Dumazetadf30902009-06-02 05:19:30 +000064 struct dst_entry *dst = skb_dst(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -070065 struct net_device *dev = dst->dev;
David S. Millerf6b72b62011-07-14 07:53:20 -070066 struct neighbour *neigh;
YOSHIFUJI Hideaki / 吉藤英明6fd6ce22013-01-17 12:54:00 +000067 struct in6_addr *nexthop;
68 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -070069
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -070070 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) {
Eric Dumazetadf30902009-06-02 05:19:30 +000071 struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
Linus Torvalds1da177e2005-04-16 15:20:36 -070072
David Miller7026b1d2015-04-05 22:19:04 -040073 if (!(dev->flags & IFF_LOOPBACK) && sk_mc_loop(sk) &&
Eric W. Biederman78126c42015-09-15 20:04:09 -050074 ((mroute6_socket(net, skb) &&
Benjamin Therybd91b8b2008-12-10 16:07:08 -080075 !(IP6CB(skb)->flags & IP6SKB_FORWARDED)) ||
YOSHIFUJI Hideaki7bc570c2008-04-03 09:22:53 +090076 ipv6_chk_mcast_addr(dev, &ipv6_hdr(skb)->daddr,
77 &ipv6_hdr(skb)->saddr))) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070078 struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
79
80 /* Do not check for IFF_ALLMULTI; multicast routing
81 is not supported in any case.
82 */
83 if (newskb)
Jan Engelhardtb2e0b382010-03-23 04:09:07 +010084 NF_HOOK(NFPROTO_IPV6, NF_INET_POST_ROUTING,
Eric W. Biederman29a26a52015-09-15 20:04:16 -050085 net, sk, newskb, NULL, newskb->dev,
Michel Machado95603e22012-06-12 10:16:35 +000086 dev_loopback_xmit);
Linus Torvalds1da177e2005-04-16 15:20:36 -070087
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -070088 if (ipv6_hdr(skb)->hop_limit == 0) {
Eric W. Biederman78126c42015-09-15 20:04:09 -050089 IP6_INC_STATS(net, idev,
Denis V. Lunev3bd653c2008-10-08 10:54:51 -070090 IPSTATS_MIB_OUTDISCARDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 kfree_skb(skb);
92 return 0;
93 }
94 }
95
Eric W. Biederman78126c42015-09-15 20:04:09 -050096 IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUTMCAST, skb->len);
Hannes Frederic Sowadd408512013-02-10 02:33:35 +000097
98 if (IPV6_ADDR_MC_SCOPE(&ipv6_hdr(skb)->daddr) <=
99 IPV6_ADDR_SCOPE_NODELOCAL &&
100 !(dev->flags & IFF_LOOPBACK)) {
101 kfree_skb(skb);
102 return 0;
103 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104 }
105
Roopa Prabhu14972cb2016-08-24 20:10:43 -0700106 if (lwtunnel_xmit_redirect(dst->lwtstate)) {
107 int res = lwtunnel_xmit(skb);
108
109 if (res < 0 || res == LWTUNNEL_XMIT_DONE)
110 return res;
111 }
112
YOSHIFUJI Hideaki / 吉藤英明6fd6ce22013-01-17 12:54:00 +0000113 rcu_read_lock_bh();
Martin KaFai Lau2647a9b2015-05-22 20:55:58 -0700114 nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
YOSHIFUJI Hideaki / 吉藤英明6fd6ce22013-01-17 12:54:00 +0000115 neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
116 if (unlikely(!neigh))
117 neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
118 if (!IS_ERR(neigh)) {
119 ret = dst_neigh_output(dst, neigh, skb);
120 rcu_read_unlock_bh();
121 return ret;
122 }
123 rcu_read_unlock_bh();
David S. Miller05e3aa02011-07-16 17:26:00 -0700124
Eric W. Biederman78126c42015-09-15 20:04:09 -0500125 IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES);
Jan Engelhardt9e508492010-04-13 15:28:11 +0200126 kfree_skb(skb);
127 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128}
129
Eric W. Biederman0c4b51f2015-09-15 20:04:18 -0500130static int ip6_finish_output(struct net *net, struct sock *sk, struct sk_buff *skb)
Jan Engelhardt9e508492010-04-13 15:28:11 +0200131{
Daniel Mack9290d742016-11-23 16:52:29 +0100132 int ret;
133
134 ret = BPF_CGROUP_RUN_PROG_INET_EGRESS(sk, skb);
135 if (ret) {
136 kfree_skb(skb);
137 return ret;
138 }
139
Jan Engelhardt9e508492010-04-13 15:28:11 +0200140 if ((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) ||
Jiri Pirko9037c352013-11-06 17:52:19 +0100141 dst_allfrag(skb_dst(skb)) ||
142 (IP6CB(skb)->frag_max_size && skb->len > IP6CB(skb)->frag_max_size))
Eric W. Biederman7d8c6e32015-06-12 22:12:04 -0500143 return ip6_fragment(net, sk, skb, ip6_finish_output2);
Jan Engelhardt9e508492010-04-13 15:28:11 +0200144 else
Eric W. Biederman7d8c6e32015-06-12 22:12:04 -0500145 return ip6_finish_output2(net, sk, skb);
Jan Engelhardt9e508492010-04-13 15:28:11 +0200146}
147
Eric W. Biedermanede20592015-10-07 16:48:47 -0500148int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149{
Jan Engelhardt9e508492010-04-13 15:28:11 +0200150 struct net_device *dev = skb_dst(skb)->dev;
Eric Dumazetadf30902009-06-02 05:19:30 +0000151 struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
Eric W. Biedermanbe10de02015-09-17 17:21:31 -0500152
Chenbo Feng2c4f58a2017-06-09 12:06:07 -0700153 skb->protocol = htons(ETH_P_IPV6);
154 skb->dev = dev;
155
YOSHIFUJI Hideaki778d80b2008-06-28 14:17:11 +0900156 if (unlikely(idev->cnf.disable_ipv6)) {
Eric W. Biederman19a06442015-09-15 20:04:10 -0500157 IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
YOSHIFUJI Hideaki778d80b2008-06-28 14:17:11 +0900158 kfree_skb(skb);
159 return 0;
160 }
161
Eric W. Biederman29a26a52015-09-15 20:04:16 -0500162 return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
163 net, sk, skb, NULL, dev,
Jan Engelhardt9c6eb282010-04-13 15:32:16 +0200164 ip6_finish_output,
165 !(IP6CB(skb)->flags & IP6SKB_REROUTED));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700166}
167
Ben Hutchings8b0d3e82018-01-22 20:06:42 +0000168bool ip6_autoflowlabel(struct net *net, const struct ipv6_pinfo *np)
Shaohua Lib3b56032017-12-20 12:10:21 -0800169{
170 if (!np->autoflowlabel_set)
171 return ip6_default_np_autolabel(net);
172 else
173 return np->autoflowlabel;
174}
175
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176/*
Eric Dumazet1c1e9d22015-09-25 07:39:20 -0700177 * xmit an sk_buff (used by TCP, SCTP and DCCP)
178 * Note : socket lock is not held for SYNACK packets, but might be modified
179 * by calls to skb_set_owner_w() and ipv6_local_error(),
180 * which are using proper atomic operations or spinlocks.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700181 */
Eric Dumazet1c1e9d22015-09-25 07:39:20 -0700182int ip6_xmit(const struct sock *sk, struct sk_buff *skb, struct flowi6 *fl6,
Pablo Neira0d4c19e2017-01-26 22:56:21 +0100183 __u32 mark, struct ipv6_txoptions *opt, int tclass)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700184{
Denis V. Lunev3bd653c2008-10-08 10:54:51 -0700185 struct net *net = sock_net(sk);
Eric Dumazet1c1e9d22015-09-25 07:39:20 -0700186 const struct ipv6_pinfo *np = inet6_sk(sk);
David S. Miller4c9483b2011-03-12 16:22:43 -0500187 struct in6_addr *first_hop = &fl6->daddr;
Eric Dumazetadf30902009-06-02 05:19:30 +0000188 struct dst_entry *dst = skb_dst(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189 struct ipv6hdr *hdr;
David S. Miller4c9483b2011-03-12 16:22:43 -0500190 u8 proto = fl6->flowi6_proto;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191 int seg_len = skb->len;
Gerrit Renkere651f032009-08-09 08:12:48 +0000192 int hlimit = -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193 u32 mtu;
194
195 if (opt) {
Chuck Leverc2636b42007-10-23 21:07:32 -0700196 unsigned int head_room;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197
198 /* First: exthdrs may take lots of space (~8K for now)
199 MAX_HEADER is not enough.
200 */
201 head_room = opt->opt_nflen + opt->opt_flen;
202 seg_len += head_room;
203 head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev);
204
205 if (skb_headroom(skb) < head_room) {
206 struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room);
Ian Morris63159f22015-03-29 14:00:04 +0100207 if (!skb2) {
Eric Dumazetadf30902009-06-02 05:19:30 +0000208 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900209 IPSTATS_MIB_OUTDISCARDS);
210 kfree_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700211 return -ENOBUFS;
212 }
Eric Dumazet808db802012-04-24 10:17:59 +0000213 consume_skb(skb);
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900214 skb = skb2;
Eric Dumazet1c1e9d22015-09-25 07:39:20 -0700215 /* skb_set_owner_w() changes sk->sk_wmem_alloc atomically,
216 * it is safe to call in our context (socket lock not held)
217 */
218 skb_set_owner_w(skb, (struct sock *)sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219 }
220 if (opt->opt_flen)
221 ipv6_push_frag_opts(skb, opt, &proto);
222 if (opt->opt_nflen)
223 ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop);
224 }
225
Arnaldo Carvalho de Meloe2d1bca2007-04-10 20:46:21 -0700226 skb_push(skb, sizeof(struct ipv6hdr));
227 skb_reset_network_header(skb);
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700228 hdr = ipv6_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700229
230 /*
231 * Fill in the IPv6 header
232 */
Eric Dumazetb903d322011-10-27 00:44:35 -0400233 if (np)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234 hlimit = np->hop_limit;
235 if (hlimit < 0)
YOSHIFUJI Hideaki6b75d092008-03-10 06:00:30 -0400236 hlimit = ip6_dst_hoplimit(dst);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700237
Tom Herbertcb1ce2e2014-07-01 21:33:10 -0700238 ip6_flow_hdr(hdr, tclass, ip6_make_flowlabel(net, skb, fl6->flowlabel,
Shaohua Lib3b56032017-12-20 12:10:21 -0800239 ip6_autoflowlabel(net, np), fl6));
YOSHIFUJI Hideaki41a1f8e2005-09-08 10:19:03 +0900240
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 hdr->payload_len = htons(seg_len);
242 hdr->nexthdr = proto;
243 hdr->hop_limit = hlimit;
244
Alexey Dobriyan4e3fd7a2011-11-21 03:39:03 +0000245 hdr->saddr = fl6->saddr;
246 hdr->daddr = *first_hop;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700247
Hannes Frederic Sowa9c9c9ad2013-08-26 12:31:23 +0200248 skb->protocol = htons(ETH_P_IPV6);
Patrick McHardya2c20642006-01-08 22:37:26 -0800249 skb->priority = sk->sk_priority;
Pablo Neira0d4c19e2017-01-26 22:56:21 +0100250 skb->mark = mark;
Patrick McHardya2c20642006-01-08 22:37:26 -0800251
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252 mtu = dst_mtu(dst);
WANG Cong60ff7462014-05-04 16:39:18 -0700253 if ((skb->len <= mtu) || skb->ignore_df || skb_is_gso(skb)) {
Eric Dumazetadf30902009-06-02 05:19:30 +0000254 IP6_UPD_PO_STATS(net, ip6_dst_idev(skb_dst(skb)),
Neil Hormanedf391f2009-04-27 02:45:02 -0700255 IPSTATS_MIB_OUT, skb->len);
David Aherna8e3e1a2016-09-10 12:09:53 -0700256
257 /* if egress device is enslaved to an L3 master device pass the
258 * skb to its handler for processing
259 */
260 skb = l3mdev_ip6_out((struct sock *)sk, skb);
261 if (unlikely(!skb))
262 return 0;
263
Eric Dumazet1c1e9d22015-09-25 07:39:20 -0700264 /* hooks should never assume socket lock is held.
265 * we promote our socket to non const
266 */
Eric W. Biederman29a26a52015-09-15 20:04:16 -0500267 return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_OUT,
Eric Dumazet1c1e9d22015-09-25 07:39:20 -0700268 net, (struct sock *)sk, skb, NULL, dst->dev,
Eric W. Biederman13206b62015-10-07 16:48:35 -0500269 dst_output);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270 }
271
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 skb->dev = dst->dev;
Eric Dumazet1c1e9d22015-09-25 07:39:20 -0700273 /* ipv6_local_error() does not require socket lock,
274 * we promote our socket to non const
275 */
276 ipv6_local_error((struct sock *)sk, EMSGSIZE, fl6, mtu);
277
Eric Dumazetadf30902009-06-02 05:19:30 +0000278 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_FRAGFAILS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279 kfree_skb(skb);
280 return -EMSGSIZE;
281}
YOSHIFUJI Hideaki71590392007-02-22 22:05:40 +0900282EXPORT_SYMBOL(ip6_xmit);
283
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284static int ip6_call_ra_chain(struct sk_buff *skb, int sel)
285{
286 struct ip6_ra_chain *ra;
287 struct sock *last = NULL;
288
289 read_lock(&ip6_ra_lock);
290 for (ra = ip6_ra_chain; ra; ra = ra->next) {
291 struct sock *sk = ra->sk;
Andrew McDonald0bd1b592005-08-09 19:44:42 -0700292 if (sk && ra->sel == sel &&
293 (!sk->sk_bound_dev_if ||
294 sk->sk_bound_dev_if == skb->dev->ifindex)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295 if (last) {
296 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
297 if (skb2)
298 rawv6_rcv(last, skb2);
299 }
300 last = sk;
301 }
302 }
303
304 if (last) {
305 rawv6_rcv(last, skb);
306 read_unlock(&ip6_ra_lock);
307 return 1;
308 }
309 read_unlock(&ip6_ra_lock);
310 return 0;
311}
312
Ville Nuorvalae21e0b52006-09-22 14:41:44 -0700313static int ip6_forward_proxy_check(struct sk_buff *skb)
314{
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700315 struct ipv6hdr *hdr = ipv6_hdr(skb);
Ville Nuorvalae21e0b52006-09-22 14:41:44 -0700316 u8 nexthdr = hdr->nexthdr;
Jesse Gross75f28112011-11-30 17:05:51 -0800317 __be16 frag_off;
Ville Nuorvalae21e0b52006-09-22 14:41:44 -0700318 int offset;
319
320 if (ipv6_ext_hdr(nexthdr)) {
Jesse Gross75f28112011-11-30 17:05:51 -0800321 offset = ipv6_skip_exthdr(skb, sizeof(*hdr), &nexthdr, &frag_off);
Ville Nuorvalae21e0b52006-09-22 14:41:44 -0700322 if (offset < 0)
323 return 0;
324 } else
325 offset = sizeof(struct ipv6hdr);
326
327 if (nexthdr == IPPROTO_ICMPV6) {
328 struct icmp6hdr *icmp6;
329
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700330 if (!pskb_may_pull(skb, (skb_network_header(skb) +
331 offset + 1 - skb->data)))
Ville Nuorvalae21e0b52006-09-22 14:41:44 -0700332 return 0;
333
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700334 icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset);
Ville Nuorvalae21e0b52006-09-22 14:41:44 -0700335
336 switch (icmp6->icmp6_type) {
337 case NDISC_ROUTER_SOLICITATION:
338 case NDISC_ROUTER_ADVERTISEMENT:
339 case NDISC_NEIGHBOUR_SOLICITATION:
340 case NDISC_NEIGHBOUR_ADVERTISEMENT:
341 case NDISC_REDIRECT:
342 /* For reaction involving unicast neighbor discovery
343 * message destined to the proxied address, pass it to
344 * input function.
345 */
346 return 1;
347 default:
348 break;
349 }
350 }
351
Ville Nuorvala74553b02006-09-22 14:42:18 -0700352 /*
353 * The proxying router can't forward traffic sent to a link-local
354 * address, so signal the sender and discard the packet. This
355 * behavior is clarified by the MIPv6 specification.
356 */
357 if (ipv6_addr_type(&hdr->daddr) & IPV6_ADDR_LINKLOCAL) {
358 dst_link_failure(skb);
359 return -1;
360 }
361
Ville Nuorvalae21e0b52006-09-22 14:41:44 -0700362 return 0;
363}
364
Eric W. Biederman0c4b51f2015-09-15 20:04:18 -0500365static inline int ip6_forward_finish(struct net *net, struct sock *sk,
366 struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367{
Jeff Barnhill584d5412018-04-05 21:29:47 +0000368 struct dst_entry *dst = skb_dst(skb);
369
370 __IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTFORWDATAGRAMS);
371 __IP6_ADD_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTOCTETS, skb->len);
372
Eric W. Biederman13206b62015-10-07 16:48:35 -0500373 return dst_output(net, sk, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374}
375
Hannes Frederic Sowa0954cf92014-01-09 10:01:16 +0100376static unsigned int ip6_dst_mtu_forward(const struct dst_entry *dst)
377{
378 unsigned int mtu;
379 struct inet6_dev *idev;
380
381 if (dst_metric_locked(dst, RTAX_MTU)) {
382 mtu = dst_metric_raw(dst, RTAX_MTU);
383 if (mtu)
384 return mtu;
385 }
386
387 mtu = IPV6_MIN_MTU;
388 rcu_read_lock();
389 idev = __in6_dev_get(dst->dev);
390 if (idev)
391 mtu = idev->cnf.mtu6;
392 rcu_read_unlock();
393
394 return mtu;
395}
396
Florian Westphalfe6cc552014-02-13 23:09:12 +0100397static bool ip6_pkt_too_big(const struct sk_buff *skb, unsigned int mtu)
398{
Florian Westphal418a3152014-05-05 00:03:34 +0200399 if (skb->len <= mtu)
Florian Westphalfe6cc552014-02-13 23:09:12 +0100400 return false;
401
WANG Cong60ff7462014-05-04 16:39:18 -0700402 /* ipv6 conntrack defrag sets max_frag_size + ignore_df */
Florian Westphalfe6cc552014-02-13 23:09:12 +0100403 if (IP6CB(skb)->frag_max_size && IP6CB(skb)->frag_max_size > mtu)
404 return true;
405
WANG Cong60ff7462014-05-04 16:39:18 -0700406 if (skb->ignore_df)
Florian Westphal418a3152014-05-05 00:03:34 +0200407 return false;
408
Marcelo Ricardo Leitnerae7ef812016-06-02 15:05:41 -0300409 if (skb_is_gso(skb) && skb_gso_validate_mtu(skb, mtu))
Florian Westphalfe6cc552014-02-13 23:09:12 +0100410 return false;
411
412 return true;
413}
414
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415int ip6_forward(struct sk_buff *skb)
416{
Eric Dumazetadf30902009-06-02 05:19:30 +0000417 struct dst_entry *dst = skb_dst(skb);
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700418 struct ipv6hdr *hdr = ipv6_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700419 struct inet6_skb_parm *opt = IP6CB(skb);
YOSHIFUJI Hideakic346dca2008-03-25 21:47:49 +0900420 struct net *net = dev_net(dst->dev);
Ulrich Weber14f3ad62010-02-26 04:34:49 -0800421 u32 mtu;
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900422
YOSHIFUJI Hideaki53b79972008-07-19 22:35:03 -0700423 if (net->ipv6.devconf_all->forwarding == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424 goto error;
425
Li RongQing090f1162014-03-11 10:40:08 +0800426 if (skb->pkt_type != PACKET_HOST)
427 goto drop;
428
Hannes Frederic Sowa9ef2e962015-10-08 18:19:53 +0200429 if (unlikely(skb->sk))
430 goto drop;
431
Ben Hutchings4497b072008-06-19 16:22:28 -0700432 if (skb_warn_if_lro(skb))
433 goto drop;
434
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435 if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700436 __IP6_INC_STATS(net, ip6_dst_idev(dst),
437 IPSTATS_MIB_INDISCARDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438 goto drop;
439 }
440
Herbert Xu35fc92a2007-03-26 23:22:20 -0700441 skb_forward_csum(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442
443 /*
444 * We DO NOT make any processing on
445 * RA packets, pushing them to user level AS IS
446 * without ane WARRANTY that application will be able
447 * to interpret them. The reason is that we
448 * cannot make anything clever here.
449 *
450 * We are not end-node, so that if packet contains
451 * AH/ESP, we cannot make anything.
452 * Defragmentation also would be mistake, RA packets
453 * cannot be fragmented, because there is no warranty
454 * that different fragments will go along one path. --ANK
455 */
YOSHIFUJI Hideaki / 吉藤英明ab4eb352013-06-22 11:13:13 +0900456 if (unlikely(opt->flags & IP6SKB_ROUTERALERT)) {
457 if (ip6_call_ra_chain(skb, ntohs(opt->ra)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700458 return 0;
459 }
460
461 /*
462 * check and decrement ttl
463 */
464 if (hdr->hop_limit <= 1) {
465 /* Force OUTPUT device used as source address */
466 skb->dev = dst->dev;
Alexey Dobriyan3ffe5332010-02-18 08:25:24 +0000467 icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT, 0);
Eric Dumazet1d015502016-04-27 16:44:40 -0700468 __IP6_INC_STATS(net, ip6_dst_idev(dst),
469 IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470
471 kfree_skb(skb);
472 return -ETIMEDOUT;
473 }
474
YOSHIFUJI Hideakifbea49e2006-09-22 14:43:49 -0700475 /* XXX: idev->cnf.proxy_ndp? */
YOSHIFUJI Hideaki53b79972008-07-19 22:35:03 -0700476 if (net->ipv6.devconf_all->proxy_ndp &&
Daniel Lezcano8a3edd82008-03-07 11:14:16 -0800477 pneigh_lookup(&nd_tbl, net, &hdr->daddr, skb->dev, 0)) {
Ville Nuorvala74553b02006-09-22 14:42:18 -0700478 int proxied = ip6_forward_proxy_check(skb);
479 if (proxied > 0)
Ville Nuorvalae21e0b52006-09-22 14:41:44 -0700480 return ip6_input(skb);
Ville Nuorvala74553b02006-09-22 14:42:18 -0700481 else if (proxied < 0) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700482 __IP6_INC_STATS(net, ip6_dst_idev(dst),
483 IPSTATS_MIB_INDISCARDS);
Ville Nuorvala74553b02006-09-22 14:42:18 -0700484 goto drop;
485 }
Ville Nuorvalae21e0b52006-09-22 14:41:44 -0700486 }
487
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488 if (!xfrm6_route_forward(skb)) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700489 __IP6_INC_STATS(net, ip6_dst_idev(dst),
490 IPSTATS_MIB_INDISCARDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491 goto drop;
492 }
Eric Dumazetadf30902009-06-02 05:19:30 +0000493 dst = skb_dst(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494
495 /* IPv6 specs say nothing about it, but it is clear that we cannot
496 send redirects to source routed frames.
Masahide NAKAMURA1e5dc142007-08-24 19:08:55 +0900497 We don't send redirects to frames decapsulated from IPsec.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498 */
David S. Millerc45a3df2012-01-27 15:32:19 -0800499 if (skb->dev == dst->dev && opt->srcrt == 0 && !skb_sec_path(skb)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700500 struct in6_addr *target = NULL;
David S. Millerfbfe95a2012-06-08 23:24:18 -0700501 struct inet_peer *peer;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700502 struct rt6_info *rt;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700503
504 /*
505 * incoming and outgoing devices are the same
506 * send a redirect.
507 */
508
509 rt = (struct rt6_info *) dst;
David S. Millerc45a3df2012-01-27 15:32:19 -0800510 if (rt->rt6i_flags & RTF_GATEWAY)
511 target = &rt->rt6i_gateway;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512 else
513 target = &hdr->daddr;
514
Martin KaFai Laufd0273d2015-05-22 20:55:57 -0700515 peer = inet_getpeer_v6(net->ipv6.peers, &hdr->daddr, 1);
David S. Miller92d86822011-02-04 15:55:25 -0800516
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517 /* Limit redirects both by destination (here)
518 and by source (inside ndisc_send_redirect)
519 */
David S. Millerfbfe95a2012-06-08 23:24:18 -0700520 if (inet_peer_xrlim_allow(peer, 1*HZ))
David S. Miller49919692012-01-27 15:30:48 -0800521 ndisc_send_redirect(skb, target);
David S. Miller1d861aa2012-07-10 03:58:16 -0700522 if (peer)
523 inet_putpeer(peer);
David L Stevens5bb1ab02007-05-09 13:53:44 -0700524 } else {
525 int addrtype = ipv6_addr_type(&hdr->saddr);
526
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527 /* This check is security critical. */
YOSHIFUJI Hideakif81b2e72008-06-25 16:55:26 +0900528 if (addrtype == IPV6_ADDR_ANY ||
529 addrtype & (IPV6_ADDR_MULTICAST | IPV6_ADDR_LOOPBACK))
David L Stevens5bb1ab02007-05-09 13:53:44 -0700530 goto error;
531 if (addrtype & IPV6_ADDR_LINKLOCAL) {
532 icmpv6_send(skb, ICMPV6_DEST_UNREACH,
Alexey Dobriyan3ffe5332010-02-18 08:25:24 +0000533 ICMPV6_NOT_NEIGHBOUR, 0);
David L Stevens5bb1ab02007-05-09 13:53:44 -0700534 goto error;
535 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 }
537
Hannes Frederic Sowa0954cf92014-01-09 10:01:16 +0100538 mtu = ip6_dst_mtu_forward(dst);
Ulrich Weber14f3ad62010-02-26 04:34:49 -0800539 if (mtu < IPV6_MIN_MTU)
540 mtu = IPV6_MIN_MTU;
541
Florian Westphalfe6cc552014-02-13 23:09:12 +0100542 if (ip6_pkt_too_big(skb, mtu)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543 /* Again, force OUTPUT device used as source address */
544 skb->dev = dst->dev;
Ulrich Weber14f3ad62010-02-26 04:34:49 -0800545 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
Eric Dumazet1d015502016-04-27 16:44:40 -0700546 __IP6_INC_STATS(net, ip6_dst_idev(dst),
547 IPSTATS_MIB_INTOOBIGERRORS);
548 __IP6_INC_STATS(net, ip6_dst_idev(dst),
549 IPSTATS_MIB_FRAGFAILS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550 kfree_skb(skb);
551 return -EMSGSIZE;
552 }
553
554 if (skb_cow(skb, dst->dev->hard_header_len)) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700555 __IP6_INC_STATS(net, ip6_dst_idev(dst),
556 IPSTATS_MIB_OUTDISCARDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557 goto drop;
558 }
559
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700560 hdr = ipv6_hdr(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700561
562 /* Mangling hops number delayed to point after skb COW */
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900563
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564 hdr->hop_limit--;
565
Eric W. Biederman29a26a52015-09-15 20:04:16 -0500566 return NF_HOOK(NFPROTO_IPV6, NF_INET_FORWARD,
567 net, NULL, skb, skb->dev, dst->dev,
Patrick McHardy6e23ae22007-11-19 18:53:30 -0800568 ip6_forward_finish);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700569
570error:
Eric Dumazet1d015502016-04-27 16:44:40 -0700571 __IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_INADDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572drop:
573 kfree_skb(skb);
574 return -EINVAL;
575}
576
577static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from)
578{
579 to->pkt_type = from->pkt_type;
580 to->priority = from->priority;
581 to->protocol = from->protocol;
Eric Dumazetadf30902009-06-02 05:19:30 +0000582 skb_dst_drop(to);
583 skb_dst_set(to, dst_clone(skb_dst(from)));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584 to->dev = from->dev;
Thomas Graf82e91ff2006-11-09 15:19:14 -0800585 to->mark = from->mark;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586
587#ifdef CONFIG_NET_SCHED
588 to->tc_index = from->tc_index;
589#endif
Yasuyuki Kozakaie7ac05f2007-03-14 16:44:01 -0700590 nf_copy(to, from);
James Morris984bc162006-06-09 00:29:17 -0700591 skb_copy_secmark(to, from);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592}
593
Eric W. Biederman7d8c6e32015-06-12 22:12:04 -0500594int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
595 int (*output)(struct net *, struct sock *, struct sk_buff *))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 struct sk_buff *frag;
Ian Morris67ba4152014-08-24 21:53:10 +0100598 struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
hannes@stressinduktion.orgf60e5992015-04-01 17:07:44 +0200599 struct ipv6_pinfo *np = skb->sk && !dev_recursion_level() ?
600 inet6_sk(skb->sk) : NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 struct ipv6hdr *tmp_hdr;
602 struct frag_hdr *fh;
603 unsigned int mtu, hlen, left, len;
Herbert Xua7ae1992011-11-18 02:20:04 +0000604 int hroom, troom;
Martin KaFai Lau286c2342015-05-22 20:55:56 -0700605 __be32 frag_id;
Ian Morris67ba4152014-08-24 21:53:10 +0100606 int ptr, offset = 0, err = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607 u8 *prevhdr, nexthdr = 0;
608
David S. Miller3fa202e2017-05-17 22:54:11 -0400609 err = ip6_find_1stfragopt(skb, &prevhdr);
610 if (err < 0)
Craig Galleka2c845e2017-05-16 14:36:23 -0400611 goto fail;
David S. Miller3fa202e2017-05-17 22:54:11 -0400612 hlen = err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 nexthdr = *prevhdr;
614
John Heffner628a5c52007-04-20 15:53:27 -0700615 mtu = ip6_skb_dst_mtu(skb);
John Heffnerb881ef72007-04-20 15:52:39 -0700616
617 /* We must not fragment if the socket is set to force MTU discovery
Ulrich Weber14f3ad62010-02-26 04:34:49 -0800618 * or if the skb it not generated by a local socket.
John Heffnerb881ef72007-04-20 15:52:39 -0700619 */
Florian Westphal485fca62015-05-22 00:44:16 +0200620 if (unlikely(!skb->ignore_df && skb->len > mtu))
621 goto fail_toobig;
Eric Dumazeta34a1012012-05-18 21:51:44 +0000622
Florian Westphal485fca62015-05-22 00:44:16 +0200623 if (IP6CB(skb)->frag_max_size) {
624 if (IP6CB(skb)->frag_max_size > mtu)
625 goto fail_toobig;
626
627 /* don't send fragments larger than what we received */
628 mtu = IP6CB(skb)->frag_max_size;
629 if (mtu < IPV6_MIN_MTU)
630 mtu = IPV6_MIN_MTU;
John Heffnerb881ef72007-04-20 15:52:39 -0700631 }
632
YOSHIFUJI Hideakid91675f2006-02-24 13:18:33 -0800633 if (np && np->frag_size < mtu) {
634 if (np->frag_size)
635 mtu = np->frag_size;
636 }
Hannes Frederic Sowa89bc7842015-10-28 13:21:04 +0100637 if (mtu < hlen + sizeof(struct frag_hdr) + 8)
Hannes Frederic Sowab72a2b02015-10-16 11:32:43 +0200638 goto fail_toobig;
Hannes Frederic Sowa1e0d69a2015-10-28 13:21:03 +0100639 mtu -= hlen + sizeof(struct frag_hdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640
Martin KaFai Laufd0273d2015-05-22 20:55:57 -0700641 frag_id = ipv6_select_ident(net, &ipv6_hdr(skb)->daddr,
642 &ipv6_hdr(skb)->saddr);
Martin KaFai Lau286c2342015-05-22 20:55:56 -0700643
Hannes Frederic Sowa405c92f2015-10-27 22:40:42 +0100644 if (skb->ip_summed == CHECKSUM_PARTIAL &&
645 (err = skb_checksum_help(skb)))
646 goto fail;
647
Florian Westphal1d325d22015-09-16 17:26:14 +0200648 hroom = LL_RESERVED_SPACE(rt->dst.dev);
David S. Miller21dc3302010-08-23 00:13:46 -0700649 if (skb_has_frag_list(skb)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650 int first_len = skb_pagelen(skb);
Eric Dumazet3d130082010-09-21 08:47:45 +0000651 struct sk_buff *frag2;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652
653 if (first_len - hlen > mtu ||
654 ((first_len - hlen) & 7) ||
Florian Westphal1d325d22015-09-16 17:26:14 +0200655 skb_cloned(skb) ||
656 skb_headroom(skb) < (hroom + sizeof(struct frag_hdr)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 goto slow_path;
658
David S. Miller4d9092b2009-06-09 00:20:05 -0700659 skb_walk_frags(skb, frag) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660 /* Correct geometry. */
661 if (frag->len > mtu ||
662 ((frag->len & 7) && frag->next) ||
Florian Westphal1d325d22015-09-16 17:26:14 +0200663 skb_headroom(frag) < (hlen + hroom + sizeof(struct frag_hdr)))
Eric Dumazet3d130082010-09-21 08:47:45 +0000664 goto slow_path_clean;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666 /* Partially cloned skb? */
667 if (skb_shared(frag))
Eric Dumazet3d130082010-09-21 08:47:45 +0000668 goto slow_path_clean;
Herbert Xu2fdba6b2005-05-18 22:52:33 -0700669
670 BUG_ON(frag->sk);
671 if (skb->sk) {
Herbert Xu2fdba6b2005-05-18 22:52:33 -0700672 frag->sk = skb->sk;
673 frag->destructor = sock_wfree;
Herbert Xu2fdba6b2005-05-18 22:52:33 -0700674 }
Eric Dumazet3d130082010-09-21 08:47:45 +0000675 skb->truesize -= frag->truesize;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700676 }
677
678 err = 0;
679 offset = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700680 /* BUILD HEADER */
681
YOSHIFUJI Hideaki9a217a12006-12-05 13:47:21 -0800682 *prevhdr = NEXTHDR_FRAGMENT;
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700683 tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684 if (!tmp_hdr) {
Florian Westphal1d325d22015-09-16 17:26:14 +0200685 err = -ENOMEM;
686 goto fail;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687 }
Florian Westphal1d325d22015-09-16 17:26:14 +0200688 frag = skb_shinfo(skb)->frag_list;
689 skb_frag_list_init(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700690
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691 __skb_pull(skb, hlen);
Ian Morris67ba4152014-08-24 21:53:10 +0100692 fh = (struct frag_hdr *)__skb_push(skb, sizeof(struct frag_hdr));
Arnaldo Carvalho de Meloe2d1bca2007-04-10 20:46:21 -0700693 __skb_push(skb, hlen);
694 skb_reset_network_header(skb);
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700695 memcpy(skb_network_header(skb), tmp_hdr, hlen);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697 fh->nexthdr = nexthdr;
698 fh->reserved = 0;
699 fh->frag_off = htons(IP6_MF);
Martin KaFai Lau286c2342015-05-22 20:55:56 -0700700 fh->identification = frag_id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701
702 first_len = skb_pagelen(skb);
703 skb->data_len = first_len - skb_headlen(skb);
704 skb->len = first_len;
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700705 ipv6_hdr(skb)->payload_len = htons(first_len -
706 sizeof(struct ipv6hdr));
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900707
Changli Gaod8d1f302010-06-10 23:31:35 -0700708 dst_hold(&rt->dst);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709
710 for (;;) {
711 /* Prepare header of the next frame,
712 * before previous one went down. */
713 if (frag) {
714 frag->ip_summed = CHECKSUM_NONE;
Arnaldo Carvalho de Melobadff6d2007-03-13 13:06:52 -0300715 skb_reset_transport_header(frag);
Ian Morris67ba4152014-08-24 21:53:10 +0100716 fh = (struct frag_hdr *)__skb_push(frag, sizeof(struct frag_hdr));
Arnaldo Carvalho de Meloe2d1bca2007-04-10 20:46:21 -0700717 __skb_push(frag, hlen);
718 skb_reset_network_header(frag);
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700719 memcpy(skb_network_header(frag), tmp_hdr,
720 hlen);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721 offset += skb->len - hlen - sizeof(struct frag_hdr);
722 fh->nexthdr = nexthdr;
723 fh->reserved = 0;
724 fh->frag_off = htons(offset);
Ian Morris53b24b82015-03-29 14:00:05 +0100725 if (frag->next)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726 fh->frag_off |= htons(IP6_MF);
727 fh->identification = frag_id;
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700728 ipv6_hdr(frag)->payload_len =
729 htons(frag->len -
730 sizeof(struct ipv6hdr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731 ip6_copy_metadata(frag, skb);
732 }
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900733
Eric W. Biederman7d8c6e32015-06-12 22:12:04 -0500734 err = output(net, sk, skb);
Ian Morris67ba4152014-08-24 21:53:10 +0100735 if (!err)
Changli Gaod8d1f302010-06-10 23:31:35 -0700736 IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
Denis V. Lunev3bd653c2008-10-08 10:54:51 -0700737 IPSTATS_MIB_FRAGCREATES);
Wei Dongdafee492006-08-02 13:41:21 -0700738
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739 if (err || !frag)
740 break;
741
742 skb = frag;
743 frag = skb->next;
744 skb->next = NULL;
745 }
746
Jesper Juhla51482b2005-11-08 09:41:34 -0800747 kfree(tmp_hdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748
749 if (err == 0) {
Changli Gaod8d1f302010-06-10 23:31:35 -0700750 IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
Denis V. Lunev3bd653c2008-10-08 10:54:51 -0700751 IPSTATS_MIB_FRAGOKS);
Amerigo Wang94e187c2012-10-29 00:13:19 +0000752 ip6_rt_put(rt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753 return 0;
754 }
755
Florian Westphal46cfd722014-09-10 01:08:46 +0200756 kfree_skb_list(frag);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757
Changli Gaod8d1f302010-06-10 23:31:35 -0700758 IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
Denis V. Lunev3bd653c2008-10-08 10:54:51 -0700759 IPSTATS_MIB_FRAGFAILS);
Amerigo Wang94e187c2012-10-29 00:13:19 +0000760 ip6_rt_put(rt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761 return err;
Eric Dumazet3d130082010-09-21 08:47:45 +0000762
763slow_path_clean:
764 skb_walk_frags(skb, frag2) {
765 if (frag2 == frag)
766 break;
767 frag2->sk = NULL;
768 frag2->destructor = NULL;
769 skb->truesize += frag2->truesize;
770 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700771 }
772
773slow_path:
774 left = skb->len - hlen; /* Space per frame */
775 ptr = hlen; /* Where to start from */
776
777 /*
778 * Fragment the datagram.
779 */
780
Herbert Xua7ae1992011-11-18 02:20:04 +0000781 troom = rt->dst.dev->needed_tailroom;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700782
783 /*
784 * Keep copying data until we run out.
785 */
Ian Morris67ba4152014-08-24 21:53:10 +0100786 while (left > 0) {
Florian Westphal683100e2017-03-13 16:24:28 +0100787 u8 *fragnexthdr_offset;
788
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789 len = left;
790 /* IF: it doesn't fit, use 'mtu' - the data space left */
791 if (len > mtu)
792 len = mtu;
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300793 /* IF: we are not sending up to and including the packet end
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794 then align the next start on an eight byte boundary */
795 if (len < left) {
796 len &= ~7;
797 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700798
Joe Perchescbffccc2014-11-05 14:39:21 -0800799 /* Allocate buffer */
800 frag = alloc_skb(len + hlen + sizeof(struct frag_hdr) +
801 hroom + troom, GFP_ATOMIC);
802 if (!frag) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700803 err = -ENOMEM;
804 goto fail;
805 }
806
807 /*
808 * Set up data on packet
809 */
810
811 ip6_copy_metadata(frag, skb);
Herbert Xua7ae1992011-11-18 02:20:04 +0000812 skb_reserve(frag, hroom);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700813 skb_put(frag, len + hlen + sizeof(struct frag_hdr));
Arnaldo Carvalho de Meloc1d2bbe2007-04-10 20:45:18 -0700814 skb_reset_network_header(frag);
Arnaldo Carvalho de Melobadff6d2007-03-13 13:06:52 -0300815 fh = (struct frag_hdr *)(skb_network_header(frag) + hlen);
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700816 frag->transport_header = (frag->network_header + hlen +
817 sizeof(struct frag_hdr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818
819 /*
820 * Charge the memory for the fragment to any owner
821 * it might possess
822 */
823 if (skb->sk)
824 skb_set_owner_w(frag, skb->sk);
825
826 /*
827 * Copy the packet header into the new buffer.
828 */
Arnaldo Carvalho de Melod626f622007-03-27 18:55:52 -0300829 skb_copy_from_linear_data(skb, skb_network_header(frag), hlen);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830
Florian Westphal683100e2017-03-13 16:24:28 +0100831 fragnexthdr_offset = skb_network_header(frag);
832 fragnexthdr_offset += prevhdr - skb_network_header(skb);
833 *fragnexthdr_offset = NEXTHDR_FRAGMENT;
834
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835 /*
836 * Build fragment header.
837 */
838 fh->nexthdr = nexthdr;
839 fh->reserved = 0;
Martin KaFai Lau286c2342015-05-22 20:55:56 -0700840 fh->identification = frag_id;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700841
842 /*
843 * Copy a block of the IP datagram.
844 */
Himangi Saraogie3f0b862014-07-12 01:57:17 +0530845 BUG_ON(skb_copy_bits(skb, ptr, skb_transport_header(frag),
846 len));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700847 left -= len;
848
849 fh->frag_off = htons(offset);
850 if (left > 0)
851 fh->frag_off |= htons(IP6_MF);
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700852 ipv6_hdr(frag)->payload_len = htons(frag->len -
853 sizeof(struct ipv6hdr));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700854
855 ptr += len;
856 offset += len;
857
858 /*
859 * Put this fragment into the sending queue.
860 */
Eric W. Biederman7d8c6e32015-06-12 22:12:04 -0500861 err = output(net, sk, frag);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862 if (err)
863 goto fail;
Wei Dongdafee492006-08-02 13:41:21 -0700864
Eric Dumazetadf30902009-06-02 05:19:30 +0000865 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
Denis V. Lunev3bd653c2008-10-08 10:54:51 -0700866 IPSTATS_MIB_FRAGCREATES);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867 }
Eric Dumazetadf30902009-06-02 05:19:30 +0000868 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900869 IPSTATS_MIB_FRAGOKS);
Eric Dumazet808db802012-04-24 10:17:59 +0000870 consume_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700871 return err;
872
Florian Westphal485fca62015-05-22 00:44:16 +0200873fail_toobig:
874 if (skb->sk && dst_allfrag(skb_dst(skb)))
875 sk_nocaps_add(skb->sk, NETIF_F_GSO_MASK);
876
Florian Westphal485fca62015-05-22 00:44:16 +0200877 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
878 err = -EMSGSIZE;
879
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880fail:
Eric Dumazetadf30902009-06-02 05:19:30 +0000881 IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900882 IPSTATS_MIB_FRAGFAILS);
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900883 kfree_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884 return err;
885}
886
Eric Dumazetb71d1d42011-04-22 04:53:02 +0000887static inline int ip6_rt_check(const struct rt6key *rt_key,
888 const struct in6_addr *fl_addr,
889 const struct in6_addr *addr_cache)
YOSHIFUJI Hideakicf6b1982006-08-23 17:19:18 -0700890{
Eric Dumazeta02cec22010-09-22 20:43:57 +0000891 return (rt_key->plen != 128 || !ipv6_addr_equal(fl_addr, &rt_key->addr)) &&
Ian Morris63159f22015-03-29 14:00:04 +0100892 (!addr_cache || !ipv6_addr_equal(fl_addr, addr_cache));
YOSHIFUJI Hideakicf6b1982006-08-23 17:19:18 -0700893}
894
Herbert Xu497c6152006-07-30 20:19:33 -0700895static struct dst_entry *ip6_sk_dst_check(struct sock *sk,
896 struct dst_entry *dst,
Eric Dumazetb71d1d42011-04-22 04:53:02 +0000897 const struct flowi6 *fl6)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700898{
Herbert Xu497c6152006-07-30 20:19:33 -0700899 struct ipv6_pinfo *np = inet6_sk(sk);
Eric Dumazeta963a372013-06-26 04:15:07 -0700900 struct rt6_info *rt;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901
Herbert Xu497c6152006-07-30 20:19:33 -0700902 if (!dst)
903 goto out;
904
Eric Dumazeta963a372013-06-26 04:15:07 -0700905 if (dst->ops->family != AF_INET6) {
906 dst_release(dst);
907 return NULL;
908 }
909
910 rt = (struct rt6_info *)dst;
Herbert Xu497c6152006-07-30 20:19:33 -0700911 /* Yes, checking route validity in not connected
912 * case is not very simple. Take into account,
913 * that we do not support routing by source, TOS,
Ian Morris67ba4152014-08-24 21:53:10 +0100914 * and MSG_DONTROUTE --ANK (980726)
Herbert Xu497c6152006-07-30 20:19:33 -0700915 *
YOSHIFUJI Hideakicf6b1982006-08-23 17:19:18 -0700916 * 1. ip6_rt_check(): If route was host route,
917 * check that cached destination is current.
Herbert Xu497c6152006-07-30 20:19:33 -0700918 * If it is network route, we still may
919 * check its validity using saved pointer
920 * to the last used address: daddr_cache.
921 * We do not want to save whole address now,
922 * (because main consumer of this service
923 * is tcp, which has not this problem),
924 * so that the last trick works only on connected
925 * sockets.
926 * 2. oif also should be the same.
927 */
David S. Miller4c9483b2011-03-12 16:22:43 -0500928 if (ip6_rt_check(&rt->rt6i_dst, &fl6->daddr, np->daddr_cache) ||
YOSHIFUJI Hideaki8e1ef0a2006-08-29 17:15:09 -0700929#ifdef CONFIG_IPV6_SUBTREES
David S. Miller4c9483b2011-03-12 16:22:43 -0500930 ip6_rt_check(&rt->rt6i_src, &fl6->saddr, np->saddr_cache) ||
YOSHIFUJI Hideaki8e1ef0a2006-08-29 17:15:09 -0700931#endif
David Ahernca254492015-10-12 11:47:10 -0700932 (!(fl6->flowi6_flags & FLOWI_FLAG_SKIP_NH_OIF) &&
933 (fl6->flowi6_oif && fl6->flowi6_oif != dst->dev->ifindex))) {
Herbert Xu497c6152006-07-30 20:19:33 -0700934 dst_release(dst);
935 dst = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700936 }
937
Herbert Xu497c6152006-07-30 20:19:33 -0700938out:
939 return dst;
940}
941
Eric Dumazet3aef9342015-09-25 07:39:12 -0700942static int ip6_dst_lookup_tail(struct net *net, const struct sock *sk,
David S. Miller4c9483b2011-03-12 16:22:43 -0500943 struct dst_entry **dst, struct flowi6 *fl6)
Herbert Xu497c6152006-07-30 20:19:33 -0700944{
David S. Miller69cce1d2011-07-17 23:09:49 -0700945#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
946 struct neighbour *n;
David S. Miller97cac082012-07-02 22:43:47 -0700947 struct rt6_info *rt;
David S. Miller69cce1d2011-07-17 23:09:49 -0700948#endif
949 int err;
Paolo Abeni6f21c962016-01-29 12:30:19 +0100950 int flags = 0;
Herbert Xu497c6152006-07-30 20:19:33 -0700951
Markus Stenberge16e8882015-05-05 13:36:59 +0300952 /* The correct way to handle this would be to do
953 * ip6_route_get_saddr, and then ip6_route_output; however,
954 * the route-specific preferred source forces the
955 * ip6_route_output call _before_ ip6_route_get_saddr.
956 *
957 * In source specific routing (no src=any default route),
958 * ip6_route_output will fail given src=any saddr, though, so
959 * that's why we try it again later.
960 */
961 if (ipv6_addr_any(&fl6->saddr) && (!*dst || !(*dst)->error)) {
962 struct rt6_info *rt;
963 bool had_dst = *dst != NULL;
964
965 if (!had_dst)
966 *dst = ip6_route_output(net, sk, fl6);
967 rt = (*dst)->error ? NULL : (struct rt6_info *)*dst;
968 err = ip6_route_get_saddr(net, rt, &fl6->daddr,
969 sk ? inet6_sk(sk)->srcprefs : 0,
970 &fl6->saddr);
971 if (err)
972 goto out_err_release;
973
974 /* If we had an erroneous initial result, pretend it
975 * never existed and let the SA-enabled version take
976 * over.
977 */
978 if (!had_dst && (*dst)->error) {
979 dst_release(*dst);
980 *dst = NULL;
981 }
Paolo Abeni6f21c962016-01-29 12:30:19 +0100982
983 if (fl6->flowi6_oif)
984 flags |= RT6_LOOKUP_F_IFACE;
Markus Stenberge16e8882015-05-05 13:36:59 +0300985 }
986
Ian Morris63159f22015-03-29 14:00:04 +0100987 if (!*dst)
Paolo Abeni6f21c962016-01-29 12:30:19 +0100988 *dst = ip6_route_output_flags(net, sk, fl6, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700989
Ian Morrise5d08d72014-11-23 21:28:43 +0000990 err = (*dst)->error;
991 if (err)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700992 goto out_err_release;
993
Neil Horman95c385b2007-04-25 17:08:10 -0700994#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
Neil Hormane550dfb2008-09-09 13:51:35 -0700995 /*
996 * Here if the dst entry we've looked up
997 * has a neighbour entry that is in the INCOMPLETE
998 * state and the src address from the flow is
999 * marked as OPTIMISTIC, we release the found
1000 * dst entry and replace it instead with the
1001 * dst entry of the nexthop router
1002 */
Eric Dumazetc56bf6f2012-07-06 09:19:05 +02001003 rt = (struct rt6_info *) *dst;
YOSHIFUJI Hideaki / 吉藤英明707be1f2013-01-17 12:53:55 +00001004 rcu_read_lock_bh();
Martin KaFai Lau2647a9b2015-05-22 20:55:58 -07001005 n = __ipv6_neigh_lookup_noref(rt->dst.dev,
1006 rt6_nexthop(rt, &fl6->daddr));
YOSHIFUJI Hideaki / 吉藤英明707be1f2013-01-17 12:53:55 +00001007 err = n && !(n->nud_state & NUD_VALID) ? -EINVAL : 0;
1008 rcu_read_unlock_bh();
1009
1010 if (err) {
Neil Hormane550dfb2008-09-09 13:51:35 -07001011 struct inet6_ifaddr *ifp;
David S. Miller4c9483b2011-03-12 16:22:43 -05001012 struct flowi6 fl_gw6;
Neil Hormane550dfb2008-09-09 13:51:35 -07001013 int redirect;
Neil Horman95c385b2007-04-25 17:08:10 -07001014
David S. Miller4c9483b2011-03-12 16:22:43 -05001015 ifp = ipv6_get_ifaddr(net, &fl6->saddr,
Neil Hormane550dfb2008-09-09 13:51:35 -07001016 (*dst)->dev, 1);
Neil Horman95c385b2007-04-25 17:08:10 -07001017
Neil Hormane550dfb2008-09-09 13:51:35 -07001018 redirect = (ifp && ifp->flags & IFA_F_OPTIMISTIC);
1019 if (ifp)
1020 in6_ifa_put(ifp);
Neil Horman95c385b2007-04-25 17:08:10 -07001021
Neil Hormane550dfb2008-09-09 13:51:35 -07001022 if (redirect) {
1023 /*
1024 * We need to get the dst entry for the
1025 * default router instead
1026 */
1027 dst_release(*dst);
David S. Miller4c9483b2011-03-12 16:22:43 -05001028 memcpy(&fl_gw6, fl6, sizeof(struct flowi6));
1029 memset(&fl_gw6.daddr, 0, sizeof(struct in6_addr));
1030 *dst = ip6_route_output(net, sk, &fl_gw6);
Ian Morrise5d08d72014-11-23 21:28:43 +00001031 err = (*dst)->error;
1032 if (err)
Neil Hormane550dfb2008-09-09 13:51:35 -07001033 goto out_err_release;
Neil Horman95c385b2007-04-25 17:08:10 -07001034 }
Neil Hormane550dfb2008-09-09 13:51:35 -07001035 }
Neil Horman95c385b2007-04-25 17:08:10 -07001036#endif
Jonathan T. Leightoncb351da2017-05-23 21:53:34 -04001037 if (ipv6_addr_v4mapped(&fl6->saddr) &&
Willem de Bruijn98184bb2017-02-18 19:00:45 -05001038 !(ipv6_addr_v4mapped(&fl6->daddr) || ipv6_addr_any(&fl6->daddr))) {
1039 err = -EAFNOSUPPORT;
1040 goto out_err_release;
1041 }
Neil Horman95c385b2007-04-25 17:08:10 -07001042
Linus Torvalds1da177e2005-04-16 15:20:36 -07001043 return 0;
1044
1045out_err_release:
1046 dst_release(*dst);
1047 *dst = NULL;
David Ahern8a966fc2016-09-10 12:09:59 -07001048
David Ahern0d240e72016-06-16 16:24:25 -07001049 if (err == -ENETUNREACH)
1050 IP6_INC_STATS(net, NULL, IPSTATS_MIB_OUTNOROUTES);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001051 return err;
1052}
Adrian Bunk34a0b3c2005-11-29 16:28:56 -08001053
Herbert Xu497c6152006-07-30 20:19:33 -07001054/**
1055 * ip6_dst_lookup - perform route lookup on flow
1056 * @sk: socket which provides route info
1057 * @dst: pointer to dst_entry * for result
David S. Miller4c9483b2011-03-12 16:22:43 -05001058 * @fl6: flow to lookup
Herbert Xu497c6152006-07-30 20:19:33 -07001059 *
1060 * This function performs a route lookup on the given flow.
1061 *
1062 * It returns zero on success, or a standard errno code on error.
1063 */
Roopa Prabhu343d60a2015-07-30 13:34:53 -07001064int ip6_dst_lookup(struct net *net, struct sock *sk, struct dst_entry **dst,
1065 struct flowi6 *fl6)
Herbert Xu497c6152006-07-30 20:19:33 -07001066{
1067 *dst = NULL;
Roopa Prabhu343d60a2015-07-30 13:34:53 -07001068 return ip6_dst_lookup_tail(net, sk, dst, fl6);
Herbert Xu497c6152006-07-30 20:19:33 -07001069}
Arnaldo Carvalho de Melo3cf3dc62005-12-13 23:23:20 -08001070EXPORT_SYMBOL_GPL(ip6_dst_lookup);
1071
Herbert Xu497c6152006-07-30 20:19:33 -07001072/**
David S. Miller68d0c6d2011-03-01 13:19:07 -08001073 * ip6_dst_lookup_flow - perform route lookup on flow with ipsec
1074 * @sk: socket which provides route info
David S. Miller4c9483b2011-03-12 16:22:43 -05001075 * @fl6: flow to lookup
David S. Miller68d0c6d2011-03-01 13:19:07 -08001076 * @final_dst: final destination address for ipsec lookup
David S. Miller68d0c6d2011-03-01 13:19:07 -08001077 *
1078 * This function performs a route lookup on the given flow.
1079 *
1080 * It returns a valid dst pointer on success, or a pointer encoded
1081 * error code.
1082 */
Eric Dumazet3aef9342015-09-25 07:39:12 -07001083struct dst_entry *ip6_dst_lookup_flow(const struct sock *sk, struct flowi6 *fl6,
Steffen Klassert0e0d44a2013-08-28 08:04:14 +02001084 const struct in6_addr *final_dst)
David S. Miller68d0c6d2011-03-01 13:19:07 -08001085{
1086 struct dst_entry *dst = NULL;
1087 int err;
1088
Roopa Prabhu343d60a2015-07-30 13:34:53 -07001089 err = ip6_dst_lookup_tail(sock_net(sk), sk, &dst, fl6);
David S. Miller68d0c6d2011-03-01 13:19:07 -08001090 if (err)
1091 return ERR_PTR(err);
1092 if (final_dst)
Alexey Dobriyan4e3fd7a2011-11-21 03:39:03 +00001093 fl6->daddr = *final_dst;
David S. Miller2774c132011-03-01 14:59:04 -08001094
Steffen Klassertf92ee612014-09-16 10:08:40 +02001095 return xfrm_lookup_route(sock_net(sk), dst, flowi6_to_flowi(fl6), sk, 0);
David S. Miller68d0c6d2011-03-01 13:19:07 -08001096}
1097EXPORT_SYMBOL_GPL(ip6_dst_lookup_flow);
1098
1099/**
1100 * ip6_sk_dst_lookup_flow - perform socket cached route lookup on flow
1101 * @sk: socket which provides the dst cache and route info
David S. Miller4c9483b2011-03-12 16:22:43 -05001102 * @fl6: flow to lookup
David S. Miller68d0c6d2011-03-01 13:19:07 -08001103 * @final_dst: final destination address for ipsec lookup
Herbert Xu497c6152006-07-30 20:19:33 -07001104 *
1105 * This function performs a route lookup on the given flow with the
1106 * possibility of using the cached route in the socket if it is valid.
1107 * It will take the socket dst lock when operating on the dst cache.
1108 * As a result, this function can only be used in process context.
1109 *
David S. Miller68d0c6d2011-03-01 13:19:07 -08001110 * It returns a valid dst pointer on success, or a pointer encoded
1111 * error code.
Herbert Xu497c6152006-07-30 20:19:33 -07001112 */
David S. Miller4c9483b2011-03-12 16:22:43 -05001113struct dst_entry *ip6_sk_dst_lookup_flow(struct sock *sk, struct flowi6 *fl6,
Steffen Klassert0e0d44a2013-08-28 08:04:14 +02001114 const struct in6_addr *final_dst)
Herbert Xu497c6152006-07-30 20:19:33 -07001115{
David S. Miller68d0c6d2011-03-01 13:19:07 -08001116 struct dst_entry *dst = sk_dst_check(sk, inet6_sk(sk)->dst_cookie);
Herbert Xu497c6152006-07-30 20:19:33 -07001117
David S. Miller4c9483b2011-03-12 16:22:43 -05001118 dst = ip6_sk_dst_check(sk, dst, fl6);
Jakub Sitnicki00bc0ef2016-06-08 15:13:34 +02001119 if (!dst)
1120 dst = ip6_dst_lookup_flow(sk, fl6, final_dst);
David S. Miller68d0c6d2011-03-01 13:19:07 -08001121
Jakub Sitnicki00bc0ef2016-06-08 15:13:34 +02001122 return dst;
Herbert Xu497c6152006-07-30 20:19:33 -07001123}
David S. Miller68d0c6d2011-03-01 13:19:07 -08001124EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup_flow);
Herbert Xu497c6152006-07-30 20:19:33 -07001125
Adrian Bunk34a0b3c2005-11-29 16:28:56 -08001126static inline int ip6_ufo_append_data(struct sock *sk,
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001127 struct sk_buff_head *queue,
Ananda Rajue89e9cf2005-10-18 15:46:41 -07001128 int getfrag(void *from, char *to, int offset, int len,
1129 int odd, struct sk_buff *skb),
1130 void *from, int length, int hh_len, int fragheaderlen,
Jakub Sitnicki3ba34582016-04-05 18:41:08 +02001131 int exthdrlen, int transhdrlen, int mtu,
1132 unsigned int flags, const struct flowi6 *fl6)
Ananda Rajue89e9cf2005-10-18 15:46:41 -07001133
1134{
1135 struct sk_buff *skb;
1136 int err;
1137
1138 /* There is support for UDP large send offload by network
1139 * device, so create one single skb packet containing complete
1140 * udp datagram
1141 */
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001142 skb = skb_peek_tail(queue);
Ian Morris63159f22015-03-29 14:00:04 +01001143 if (!skb) {
Ananda Rajue89e9cf2005-10-18 15:46:41 -07001144 skb = sock_alloc_send_skb(sk,
1145 hh_len + fragheaderlen + transhdrlen + 20,
1146 (flags & MSG_DONTWAIT), &err);
Ian Morris63159f22015-03-29 14:00:04 +01001147 if (!skb)
Zheng Yan504744e2011-10-28 00:26:00 -04001148 return err;
Ananda Rajue89e9cf2005-10-18 15:46:41 -07001149
1150 /* reserve space for Hardware header */
1151 skb_reserve(skb, hh_len);
1152
1153 /* create space for UDP/IP header */
Ian Morris67ba4152014-08-24 21:53:10 +01001154 skb_put(skb, fragheaderlen + transhdrlen);
Ananda Rajue89e9cf2005-10-18 15:46:41 -07001155
1156 /* initialize network header pointer */
Jakub Sitnicki3ba34582016-04-05 18:41:08 +02001157 skb_set_network_header(skb, exthdrlen);
Ananda Rajue89e9cf2005-10-18 15:46:41 -07001158
1159 /* initialize protocol header pointer */
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -07001160 skb->transport_header = skb->network_header + fragheaderlen;
Ananda Rajue89e9cf2005-10-18 15:46:41 -07001161
Hannes Frederic Sowa9c9c9ad2013-08-26 12:31:23 +02001162 skb->protocol = htons(ETH_P_IPV6);
Ananda Rajue89e9cf2005-10-18 15:46:41 -07001163 skb->csum = 0;
Ananda Rajue89e9cf2005-10-18 15:46:41 -07001164
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001165 __skb_queue_tail(queue, skb);
Jiri Pirkoc547dbf2013-10-19 12:29:16 +02001166 } else if (skb_is_gso(skb)) {
1167 goto append;
Ananda Rajue89e9cf2005-10-18 15:46:41 -07001168 }
Ananda Rajue89e9cf2005-10-18 15:46:41 -07001169
Jiri Pirkoc547dbf2013-10-19 12:29:16 +02001170 skb->ip_summed = CHECKSUM_PARTIAL;
1171 /* Specify the length of each IPv6 datagram fragment.
1172 * It has to be a multiple of 8.
1173 */
1174 skb_shinfo(skb)->gso_size = (mtu - fragheaderlen -
1175 sizeof(struct frag_hdr)) & ~7;
1176 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
Martin KaFai Laufd0273d2015-05-22 20:55:57 -07001177 skb_shinfo(skb)->ip6_frag_id = ipv6_select_ident(sock_net(sk),
1178 &fl6->daddr,
1179 &fl6->saddr);
Jiri Pirkoc547dbf2013-10-19 12:29:16 +02001180
1181append:
Hannes Frederic Sowa2811eba2013-09-21 06:27:00 +02001182 return skb_append_datato_frags(sk, skb, getfrag, from,
1183 (length - transhdrlen));
Ananda Rajue89e9cf2005-10-18 15:46:41 -07001184}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001185
Herbert Xu0178b692009-02-05 15:15:50 -08001186static inline struct ipv6_opt_hdr *ip6_opt_dup(struct ipv6_opt_hdr *src,
1187 gfp_t gfp)
1188{
1189 return src ? kmemdup(src, (src->hdrlen + 1) * 8, gfp) : NULL;
1190}
1191
1192static inline struct ipv6_rt_hdr *ip6_rthdr_dup(struct ipv6_rt_hdr *src,
1193 gfp_t gfp)
1194{
1195 return src ? kmemdup(src, (src->hdrlen + 1) * 8, gfp) : NULL;
1196}
1197
Hannes Frederic Sowa75a493e2013-07-02 08:04:05 +02001198static void ip6_append_data_mtu(unsigned int *mtu,
Gao feng0c183372012-05-26 01:30:53 +00001199 int *maxfraglen,
1200 unsigned int fragheaderlen,
1201 struct sk_buff *skb,
Hannes Frederic Sowa75a493e2013-07-02 08:04:05 +02001202 struct rt6_info *rt,
luciene367c2d2014-03-17 12:51:01 +08001203 unsigned int orig_mtu)
Gao feng0c183372012-05-26 01:30:53 +00001204{
1205 if (!(rt->dst.flags & DST_XFRM_TUNNEL)) {
Ian Morris63159f22015-03-29 14:00:04 +01001206 if (!skb) {
Gao feng0c183372012-05-26 01:30:53 +00001207 /* first fragment, reserve header_len */
luciene367c2d2014-03-17 12:51:01 +08001208 *mtu = orig_mtu - rt->dst.header_len;
Gao feng0c183372012-05-26 01:30:53 +00001209
1210 } else {
1211 /*
1212 * this fragment is not first, the headers
1213 * space is regarded as data space.
1214 */
luciene367c2d2014-03-17 12:51:01 +08001215 *mtu = orig_mtu;
Gao feng0c183372012-05-26 01:30:53 +00001216 }
1217 *maxfraglen = ((*mtu - fragheaderlen) & ~7)
1218 + fragheaderlen - sizeof(struct frag_hdr);
1219 }
1220}
1221
Vlad Yasevich366e41d2015-01-31 10:40:13 -05001222static int ip6_setup_cork(struct sock *sk, struct inet_cork_full *cork,
Wei Wang26879da2016-05-02 21:40:07 -07001223 struct inet6_cork *v6_cork, struct ipcm6_cookie *ipc6,
Vlad Yasevich366e41d2015-01-31 10:40:13 -05001224 struct rt6_info *rt, struct flowi6 *fl6)
1225{
1226 struct ipv6_pinfo *np = inet6_sk(sk);
1227 unsigned int mtu;
Wei Wang26879da2016-05-02 21:40:07 -07001228 struct ipv6_txoptions *opt = ipc6->opt;
Vlad Yasevich366e41d2015-01-31 10:40:13 -05001229
1230 /*
1231 * setup for corking
1232 */
1233 if (opt) {
1234 if (WARN_ON(v6_cork->opt))
1235 return -EINVAL;
1236
Eric Dumazet28fa5832017-10-21 12:26:23 -07001237 v6_cork->opt = kzalloc(sizeof(*opt), sk->sk_allocation);
Ian Morris63159f22015-03-29 14:00:04 +01001238 if (unlikely(!v6_cork->opt))
Vlad Yasevich366e41d2015-01-31 10:40:13 -05001239 return -ENOBUFS;
1240
Eric Dumazet28fa5832017-10-21 12:26:23 -07001241 v6_cork->opt->tot_len = sizeof(*opt);
Vlad Yasevich366e41d2015-01-31 10:40:13 -05001242 v6_cork->opt->opt_flen = opt->opt_flen;
1243 v6_cork->opt->opt_nflen = opt->opt_nflen;
1244
1245 v6_cork->opt->dst0opt = ip6_opt_dup(opt->dst0opt,
1246 sk->sk_allocation);
1247 if (opt->dst0opt && !v6_cork->opt->dst0opt)
1248 return -ENOBUFS;
1249
1250 v6_cork->opt->dst1opt = ip6_opt_dup(opt->dst1opt,
1251 sk->sk_allocation);
1252 if (opt->dst1opt && !v6_cork->opt->dst1opt)
1253 return -ENOBUFS;
1254
1255 v6_cork->opt->hopopt = ip6_opt_dup(opt->hopopt,
1256 sk->sk_allocation);
1257 if (opt->hopopt && !v6_cork->opt->hopopt)
1258 return -ENOBUFS;
1259
1260 v6_cork->opt->srcrt = ip6_rthdr_dup(opt->srcrt,
1261 sk->sk_allocation);
1262 if (opt->srcrt && !v6_cork->opt->srcrt)
1263 return -ENOBUFS;
1264
1265 /* need source address above miyazawa*/
1266 }
1267 dst_hold(&rt->dst);
1268 cork->base.dst = &rt->dst;
1269 cork->fl.u.ip6 = *fl6;
Wei Wang26879da2016-05-02 21:40:07 -07001270 v6_cork->hop_limit = ipc6->hlimit;
1271 v6_cork->tclass = ipc6->tclass;
Vlad Yasevich366e41d2015-01-31 10:40:13 -05001272 if (rt->dst.flags & DST_XFRM_TUNNEL)
1273 mtu = np->pmtudisc >= IPV6_PMTUDISC_PROBE ?
Mike Maloneyfb50d8c2018-01-10 12:45:10 -05001274 READ_ONCE(rt->dst.dev->mtu) : dst_mtu(&rt->dst);
Vlad Yasevich366e41d2015-01-31 10:40:13 -05001275 else
1276 mtu = np->pmtudisc >= IPV6_PMTUDISC_PROBE ?
Mike Maloneyfb50d8c2018-01-10 12:45:10 -05001277 READ_ONCE(rt->dst.dev->mtu) : dst_mtu(rt->dst.path);
Vlad Yasevich366e41d2015-01-31 10:40:13 -05001278 if (np->frag_size < mtu) {
1279 if (np->frag_size)
1280 mtu = np->frag_size;
1281 }
Ashwanth Goli1d738572018-05-09 19:57:01 +05301282 if (!(rt->dst.flags & DST_XFRM_TUNNEL) && mtu < IPV6_MIN_MTU)
Mike Maloneyfb50d8c2018-01-10 12:45:10 -05001283 return -EINVAL;
Vlad Yasevich366e41d2015-01-31 10:40:13 -05001284 cork->base.fragsize = mtu;
1285 if (dst_allfrag(rt->dst.path))
1286 cork->base.flags |= IPCORK_ALLFRAG;
1287 cork->base.length = 0;
1288
1289 return 0;
1290}
1291
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001292static int __ip6_append_data(struct sock *sk,
1293 struct flowi6 *fl6,
1294 struct sk_buff_head *queue,
1295 struct inet_cork *cork,
1296 struct inet6_cork *v6_cork,
1297 struct page_frag *pfrag,
1298 int getfrag(void *from, char *to, int offset,
1299 int len, int odd, struct sk_buff *skb),
1300 void *from, int length, int transhdrlen,
Wei Wang26879da2016-05-02 21:40:07 -07001301 unsigned int flags, struct ipcm6_cookie *ipc6,
Soheil Hassas Yeganehc14ac942016-04-02 23:08:12 -04001302 const struct sockcm_cookie *sockc)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001303{
Gao feng0c183372012-05-26 01:30:53 +00001304 struct sk_buff *skb, *skb_prev = NULL;
Paolo Abeni81eb03e2018-03-23 14:47:30 +01001305 unsigned int maxfraglen, fragheaderlen, mtu, orig_mtu, pmtu;
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001306 int exthdrlen = 0;
1307 int dst_exthdrlen = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001308 int hh_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001309 int copy;
1310 int err;
1311 int offset = 0;
Anders Berggrena693e692011-02-28 12:32:11 -08001312 __u8 tx_flags = 0;
Willem de Bruijn09c2d252014-08-04 22:11:47 -04001313 u32 tskey = 0;
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001314 struct rt6_info *rt = (struct rt6_info *)cork->dst;
1315 struct ipv6_txoptions *opt = v6_cork->opt;
Vlad Yasevich32dce962015-01-31 10:40:18 -05001316 int csummode = CHECKSUM_NONE;
Hannes Frederic Sowa682b1a92015-10-27 22:40:41 +01001317 unsigned int maxnonfragsize, headersize;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001318
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001319 skb = skb_peek_tail(queue);
1320 if (!skb) {
1321 exthdrlen = opt ? opt->opt_flen : 0;
Romain KUNTZ7efdba52013-01-16 12:47:40 +00001322 dst_exthdrlen = rt->dst.header_len - rt->rt6i_nfheader_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001323 }
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001324
Vlad Yasevich366e41d2015-01-31 10:40:13 -05001325 mtu = cork->fragsize;
luciene367c2d2014-03-17 12:51:01 +08001326 orig_mtu = mtu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001327
Changli Gaod8d1f302010-06-10 23:31:35 -07001328 hh_len = LL_RESERVED_SPACE(rt->dst.dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001329
Masahide NAKAMURAa1b05142007-12-20 20:41:12 -08001330 fragheaderlen = sizeof(struct ipv6hdr) + rt->rt6i_nfheader_len +
Herbert Xub4ce9272007-11-13 21:33:32 -08001331 (opt ? opt->opt_nflen : 0);
Hannes Frederic Sowa4df98e72013-12-16 12:36:44 +01001332 maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen -
1333 sizeof(struct frag_hdr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001334
Hannes Frederic Sowa682b1a92015-10-27 22:40:41 +01001335 headersize = sizeof(struct ipv6hdr) +
1336 (opt ? opt->opt_flen + opt->opt_nflen : 0) +
1337 (dst_allfrag(&rt->dst) ?
1338 sizeof(struct frag_hdr) : 0) +
1339 rt->rt6i_nfheader_len;
Hannes Frederic Sowa4df98e72013-12-16 12:36:44 +01001340
Paolo Abeni81eb03e2018-03-23 14:47:30 +01001341 /* as per RFC 7112 section 5, the entire IPv6 Header Chain must fit
1342 * the first fragment
1343 */
1344 if (headersize + transhdrlen > mtu)
1345 goto emsgsize;
1346
Wei Wang26879da2016-05-02 21:40:07 -07001347 if (cork->length + length > mtu - headersize && ipc6->dontfrag &&
Hannes Frederic Sowa682b1a92015-10-27 22:40:41 +01001348 (sk->sk_protocol == IPPROTO_UDP ||
1349 sk->sk_protocol == IPPROTO_RAW)) {
1350 ipv6_local_rxpmtu(sk, fl6, mtu - headersize +
1351 sizeof(struct ipv6hdr));
1352 goto emsgsize;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001353 }
1354
Hannes Frederic Sowa682b1a92015-10-27 22:40:41 +01001355 if (ip6_sk_ignore_df(sk))
1356 maxnonfragsize = sizeof(struct ipv6hdr) + IPV6_MAXPLEN;
1357 else
1358 maxnonfragsize = mtu;
1359
1360 if (cork->length + length > maxnonfragsize - headersize) {
1361emsgsize:
Paolo Abeni81eb03e2018-03-23 14:47:30 +01001362 pmtu = max_t(int, mtu - headersize + sizeof(struct ipv6hdr), 0);
1363 ipv6_local_error(sk, EMSGSIZE, fl6, pmtu);
Hannes Frederic Sowa682b1a92015-10-27 22:40:41 +01001364 return -EMSGSIZE;
1365 }
1366
1367 /* CHECKSUM_PARTIAL only with no extension headers and when
1368 * we are not going to fragment
1369 */
1370 if (transhdrlen && sk->sk_protocol == IPPROTO_UDP &&
1371 headersize == sizeof(struct ipv6hdr) &&
1372 length < mtu - headersize &&
1373 !(flags & MSG_MORE) &&
Tom Herbertc8cd0982015-12-14 11:19:44 -08001374 rt->dst.dev->features & (NETIF_F_IPV6_CSUM | NETIF_F_HW_CSUM))
Hannes Frederic Sowa682b1a92015-10-27 22:40:41 +01001375 csummode = CHECKSUM_PARTIAL;
1376
Willem de Bruijn09c2d252014-08-04 22:11:47 -04001377 if (sk->sk_type == SOCK_DGRAM || sk->sk_type == SOCK_RAW) {
Soheil Hassas Yeganehc14ac942016-04-02 23:08:12 -04001378 sock_tx_timestamp(sk, sockc->tsflags, &tx_flags);
Willem de Bruijn09c2d252014-08-04 22:11:47 -04001379 if (tx_flags & SKBTX_ANY_SW_TSTAMP &&
1380 sk->sk_tsflags & SOF_TIMESTAMPING_OPT_ID)
1381 tskey = sk->sk_tskey++;
1382 }
Anders Berggrena693e692011-02-28 12:32:11 -08001383
Linus Torvalds1da177e2005-04-16 15:20:36 -07001384 /*
1385 * Let's try using as much space as possible.
1386 * Use MTU if total length of the message fits into the MTU.
1387 * Otherwise, we need to reserve fragment header and
1388 * fragment alignment (= 8-15 octects, in total).
1389 *
1390 * Note that we may need to "move" the data from the tail of
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +09001391 * of the buffer to the new fragment when we split
Linus Torvalds1da177e2005-04-16 15:20:36 -07001392 * the message.
1393 *
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +09001394 * FIXME: It may be fragmented into multiple chunks
Linus Torvalds1da177e2005-04-16 15:20:36 -07001395 * at once if non-fragmentable extension headers
1396 * are too large.
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +09001397 * --yoshfuji
Linus Torvalds1da177e2005-04-16 15:20:36 -07001398 */
1399
Hannes Frederic Sowa2811eba2013-09-21 06:27:00 +02001400 cork->length += length;
Willem de Bruijn33dc6a62017-08-10 12:29:19 -04001401 if ((skb && skb_is_gso(skb)) ||
1402 (((length + fragheaderlen) > mtu) &&
1403 (skb_queue_len(queue) <= 1) &&
Hannes Frederic Sowa2811eba2013-09-21 06:27:00 +02001404 (sk->sk_protocol == IPPROTO_UDP) &&
Jakub Sitnickif89c56c2016-10-26 11:21:14 +02001405 (rt->dst.dev->features & NETIF_F_UFO) && !rt->dst.header_len &&
Willem de Bruijn33dc6a62017-08-10 12:29:19 -04001406 (sk->sk_type == SOCK_DGRAM) && !udp_get_no_check6_tx(sk))) {
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001407 err = ip6_ufo_append_data(sk, queue, getfrag, from, length,
Jakub Sitnicki3ba34582016-04-05 18:41:08 +02001408 hh_len, fragheaderlen, exthdrlen,
Martin KaFai Laufd0273d2015-05-22 20:55:57 -07001409 transhdrlen, mtu, flags, fl6);
Hannes Frederic Sowa2811eba2013-09-21 06:27:00 +02001410 if (err)
1411 goto error;
1412 return 0;
1413 }
1414
1415 if (!skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001416 goto alloc_new_skb;
1417
1418 while (length > 0) {
1419 /* Check if the remaining data fits into current packet. */
David S. Millerbdc712b2011-05-06 15:02:07 -07001420 copy = (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001421 if (copy < length)
1422 copy = maxfraglen - skb->len;
1423
1424 if (copy <= 0) {
1425 char *data;
1426 unsigned int datalen;
1427 unsigned int fraglen;
1428 unsigned int fraggap;
1429 unsigned int alloclen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001430alloc_new_skb:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001431 /* There's no room in the current skb */
Gao feng0c183372012-05-26 01:30:53 +00001432 if (skb)
1433 fraggap = skb->len - maxfraglen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001434 else
1435 fraggap = 0;
Gao feng0c183372012-05-26 01:30:53 +00001436 /* update mtu and maxfraglen if necessary */
Ian Morris63159f22015-03-29 14:00:04 +01001437 if (!skb || !skb_prev)
Gao feng0c183372012-05-26 01:30:53 +00001438 ip6_append_data_mtu(&mtu, &maxfraglen,
Hannes Frederic Sowa75a493e2013-07-02 08:04:05 +02001439 fragheaderlen, skb, rt,
luciene367c2d2014-03-17 12:51:01 +08001440 orig_mtu);
Gao feng0c183372012-05-26 01:30:53 +00001441
1442 skb_prev = skb;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001443
1444 /*
1445 * If remaining data exceeds the mtu,
1446 * we know we need more fragment(s).
1447 */
1448 datalen = length + fraggap;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001449
Gao feng0c183372012-05-26 01:30:53 +00001450 if (datalen > (cork->length <= mtu && !(cork->flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen)
1451 datalen = maxfraglen - fragheaderlen - rt->dst.trailer_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001452 if ((flags & MSG_MORE) &&
Changli Gaod8d1f302010-06-10 23:31:35 -07001453 !(rt->dst.dev->features&NETIF_F_SG))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001454 alloclen = mtu;
1455 else
1456 alloclen = datalen + fragheaderlen;
1457
Steffen Klassert299b0762011-10-11 01:43:33 +00001458 alloclen += dst_exthdrlen;
1459
Gao feng0c183372012-05-26 01:30:53 +00001460 if (datalen != length + fraggap) {
1461 /*
1462 * this is not the last fragment, the trailer
1463 * space is regarded as data space.
1464 */
1465 datalen += rt->dst.trailer_len;
1466 }
1467
1468 alloclen += rt->dst.trailer_len;
1469 fraglen = datalen + fragheaderlen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001470
1471 /*
1472 * We just reserve space for fragment header.
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +09001473 * Note: this may be overallocation if the message
Linus Torvalds1da177e2005-04-16 15:20:36 -07001474 * (without MSG_MORE) fits into the MTU.
1475 */
1476 alloclen += sizeof(struct frag_hdr);
1477
Eric Dumazet304b4102017-05-19 14:17:48 -07001478 copy = datalen - transhdrlen - fraggap;
1479 if (copy < 0) {
1480 err = -EINVAL;
1481 goto error;
1482 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001483 if (transhdrlen) {
1484 skb = sock_alloc_send_skb(sk,
1485 alloclen + hh_len,
1486 (flags & MSG_DONTWAIT), &err);
1487 } else {
1488 skb = NULL;
1489 if (atomic_read(&sk->sk_wmem_alloc) <=
1490 2 * sk->sk_sndbuf)
1491 skb = sock_wmalloc(sk,
1492 alloclen + hh_len, 1,
1493 sk->sk_allocation);
Ian Morris63159f22015-03-29 14:00:04 +01001494 if (unlikely(!skb))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001495 err = -ENOBUFS;
1496 }
Ian Morris63159f22015-03-29 14:00:04 +01001497 if (!skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001498 goto error;
1499 /*
1500 * Fill in the control structures
1501 */
Hannes Frederic Sowa9c9c9ad2013-08-26 12:31:23 +02001502 skb->protocol = htons(ETH_P_IPV6);
Vlad Yasevich32dce962015-01-31 10:40:18 -05001503 skb->ip_summed = csummode;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001504 skb->csum = 0;
Gao feng1f858512012-03-19 22:36:10 +00001505 /* reserve for fragmentation and ipsec header */
1506 skb_reserve(skb, hh_len + sizeof(struct frag_hdr) +
1507 dst_exthdrlen);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001508
Willem de Bruijn11878b42014-07-14 17:55:06 -04001509 /* Only the initial fragment is time stamped */
1510 skb_shinfo(skb)->tx_flags = tx_flags;
1511 tx_flags = 0;
Willem de Bruijn09c2d252014-08-04 22:11:47 -04001512 skb_shinfo(skb)->tskey = tskey;
1513 tskey = 0;
Anders Berggrena693e692011-02-28 12:32:11 -08001514
Linus Torvalds1da177e2005-04-16 15:20:36 -07001515 /*
1516 * Find where to start putting bytes
1517 */
Gao feng1f858512012-03-19 22:36:10 +00001518 data = skb_put(skb, fraglen);
1519 skb_set_network_header(skb, exthdrlen);
1520 data += fragheaderlen;
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -07001521 skb->transport_header = (skb->network_header +
1522 fragheaderlen);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001523 if (fraggap) {
1524 skb->csum = skb_copy_and_csum_bits(
1525 skb_prev, maxfraglen,
1526 data + transhdrlen, fraggap, 0);
1527 skb_prev->csum = csum_sub(skb_prev->csum,
1528 skb->csum);
1529 data += fraggap;
Herbert Xue9fa4f72006-08-13 20:12:58 -07001530 pskb_trim_unique(skb_prev, maxfraglen);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001531 }
Eric Dumazet304b4102017-05-19 14:17:48 -07001532 if (copy > 0 &&
1533 getfrag(from, data + transhdrlen, offset,
1534 copy, fraggap, skb) < 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001535 err = -EFAULT;
1536 kfree_skb(skb);
1537 goto error;
1538 }
1539
1540 offset += copy;
1541 length -= datalen - fraggap;
1542 transhdrlen = 0;
1543 exthdrlen = 0;
Steffen Klassert299b0762011-10-11 01:43:33 +00001544 dst_exthdrlen = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001545
1546 /*
1547 * Put the packet on the pending queue
1548 */
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001549 __skb_queue_tail(queue, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001550 continue;
1551 }
1552
1553 if (copy > length)
1554 copy = length;
1555
Willem de Bruijn2ef22bd2018-05-17 13:13:29 -04001556 if (!(rt->dst.dev->features&NETIF_F_SG) &&
1557 skb_tailroom(skb) >= copy) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001558 unsigned int off;
1559
1560 off = skb->len;
1561 if (getfrag(from, skb_put(skb, copy),
1562 offset, copy, off, skb) < 0) {
1563 __skb_trim(skb, off);
1564 err = -EFAULT;
1565 goto error;
1566 }
1567 } else {
1568 int i = skb_shinfo(skb)->nr_frags;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001569
Eric Dumazet5640f762012-09-23 23:04:42 +00001570 err = -ENOMEM;
1571 if (!sk_page_frag_refill(sk, pfrag))
1572 goto error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001573
Eric Dumazet5640f762012-09-23 23:04:42 +00001574 if (!skb_can_coalesce(skb, i, pfrag->page,
1575 pfrag->offset)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001576 err = -EMSGSIZE;
Eric Dumazet5640f762012-09-23 23:04:42 +00001577 if (i == MAX_SKB_FRAGS)
1578 goto error;
1579
1580 __skb_fill_page_desc(skb, i, pfrag->page,
1581 pfrag->offset, 0);
1582 skb_shinfo(skb)->nr_frags = ++i;
1583 get_page(pfrag->page);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001584 }
Eric Dumazet5640f762012-09-23 23:04:42 +00001585 copy = min_t(int, copy, pfrag->size - pfrag->offset);
Eric Dumazet9e903e02011-10-18 21:00:24 +00001586 if (getfrag(from,
Eric Dumazet5640f762012-09-23 23:04:42 +00001587 page_address(pfrag->page) + pfrag->offset,
1588 offset, copy, skb->len, skb) < 0)
1589 goto error_efault;
1590
1591 pfrag->offset += copy;
1592 skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001593 skb->len += copy;
1594 skb->data_len += copy;
Herbert Xuf945fa72008-01-22 22:39:26 -08001595 skb->truesize += copy;
1596 atomic_add(copy, &sk->sk_wmem_alloc);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001597 }
1598 offset += copy;
1599 length -= copy;
1600 }
Eric Dumazet5640f762012-09-23 23:04:42 +00001601
Linus Torvalds1da177e2005-04-16 15:20:36 -07001602 return 0;
Eric Dumazet5640f762012-09-23 23:04:42 +00001603
1604error_efault:
1605 err = -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001606error:
David S. Millerbdc712b2011-05-06 15:02:07 -07001607 cork->length -= length;
Denis V. Lunev3bd653c2008-10-08 10:54:51 -07001608 IP6_INC_STATS(sock_net(sk), rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001609 return err;
1610}
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001611
1612int ip6_append_data(struct sock *sk,
1613 int getfrag(void *from, char *to, int offset, int len,
1614 int odd, struct sk_buff *skb),
Wei Wang26879da2016-05-02 21:40:07 -07001615 void *from, int length, int transhdrlen,
1616 struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
1617 struct rt6_info *rt, unsigned int flags,
Soheil Hassas Yeganehc14ac942016-04-02 23:08:12 -04001618 const struct sockcm_cookie *sockc)
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001619{
1620 struct inet_sock *inet = inet_sk(sk);
1621 struct ipv6_pinfo *np = inet6_sk(sk);
1622 int exthdrlen;
1623 int err;
1624
1625 if (flags&MSG_PROBE)
1626 return 0;
1627 if (skb_queue_empty(&sk->sk_write_queue)) {
1628 /*
1629 * setup for corking
1630 */
Wei Wang26879da2016-05-02 21:40:07 -07001631 err = ip6_setup_cork(sk, &inet->cork, &np->cork,
1632 ipc6, rt, fl6);
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001633 if (err)
1634 return err;
1635
Wei Wang26879da2016-05-02 21:40:07 -07001636 exthdrlen = (ipc6->opt ? ipc6->opt->opt_flen : 0);
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001637 length += exthdrlen;
1638 transhdrlen += exthdrlen;
1639 } else {
1640 fl6 = &inet->cork.fl.u.ip6;
1641 transhdrlen = 0;
1642 }
1643
1644 return __ip6_append_data(sk, fl6, &sk->sk_write_queue, &inet->cork.base,
1645 &np->cork, sk_page_frag(sk), getfrag,
Wei Wang26879da2016-05-02 21:40:07 -07001646 from, length, transhdrlen, flags, ipc6, sockc);
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001647}
Chris Elstona495f832012-04-29 21:48:53 +00001648EXPORT_SYMBOL_GPL(ip6_append_data);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001649
Vlad Yasevich366e41d2015-01-31 10:40:13 -05001650static void ip6_cork_release(struct inet_cork_full *cork,
1651 struct inet6_cork *v6_cork)
Pavel Emelyanovbf138862007-11-05 21:04:31 -08001652{
Vlad Yasevich366e41d2015-01-31 10:40:13 -05001653 if (v6_cork->opt) {
1654 kfree(v6_cork->opt->dst0opt);
1655 kfree(v6_cork->opt->dst1opt);
1656 kfree(v6_cork->opt->hopopt);
1657 kfree(v6_cork->opt->srcrt);
1658 kfree(v6_cork->opt);
1659 v6_cork->opt = NULL;
Herbert Xu0178b692009-02-05 15:15:50 -08001660 }
1661
Vlad Yasevich366e41d2015-01-31 10:40:13 -05001662 if (cork->base.dst) {
1663 dst_release(cork->base.dst);
1664 cork->base.dst = NULL;
1665 cork->base.flags &= ~IPCORK_ALLFRAG;
Pavel Emelyanovbf138862007-11-05 21:04:31 -08001666 }
Vlad Yasevich366e41d2015-01-31 10:40:13 -05001667 memset(&cork->fl, 0, sizeof(cork->fl));
Pavel Emelyanovbf138862007-11-05 21:04:31 -08001668}
1669
Vlad Yasevich64223982015-01-31 10:40:15 -05001670struct sk_buff *__ip6_make_skb(struct sock *sk,
1671 struct sk_buff_head *queue,
1672 struct inet_cork_full *cork,
1673 struct inet6_cork *v6_cork)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001674{
1675 struct sk_buff *skb, *tmp_skb;
1676 struct sk_buff **tail_skb;
1677 struct in6_addr final_dst_buf, *final_dst = &final_dst_buf;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001678 struct ipv6_pinfo *np = inet6_sk(sk);
Denis V. Lunev3bd653c2008-10-08 10:54:51 -07001679 struct net *net = sock_net(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001680 struct ipv6hdr *hdr;
Vlad Yasevich64223982015-01-31 10:40:15 -05001681 struct ipv6_txoptions *opt = v6_cork->opt;
1682 struct rt6_info *rt = (struct rt6_info *)cork->base.dst;
1683 struct flowi6 *fl6 = &cork->fl.u.ip6;
David S. Miller4c9483b2011-03-12 16:22:43 -05001684 unsigned char proto = fl6->flowi6_proto;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001685
Vlad Yasevich64223982015-01-31 10:40:15 -05001686 skb = __skb_dequeue(queue);
Ian Morris63159f22015-03-29 14:00:04 +01001687 if (!skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001688 goto out;
1689 tail_skb = &(skb_shinfo(skb)->frag_list);
1690
1691 /* move skb->data to ip header from ext header */
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -07001692 if (skb->data < skb_network_header(skb))
Arnaldo Carvalho de Melobbe735e2007-03-10 22:16:10 -03001693 __skb_pull(skb, skb_network_offset(skb));
Vlad Yasevich64223982015-01-31 10:40:15 -05001694 while ((tmp_skb = __skb_dequeue(queue)) != NULL) {
Arnaldo Carvalho de Melocfe1fc72007-03-16 17:26:39 -03001695 __skb_pull(tmp_skb, skb_network_header_len(skb));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001696 *tail_skb = tmp_skb;
1697 tail_skb = &(tmp_skb->next);
1698 skb->len += tmp_skb->len;
1699 skb->data_len += tmp_skb->len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001700 skb->truesize += tmp_skb->truesize;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001701 tmp_skb->destructor = NULL;
1702 tmp_skb->sk = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001703 }
1704
Herbert Xu28a894532008-02-12 18:07:27 -08001705 /* Allow local fragmentation. */
WANG Cong60ff7462014-05-04 16:39:18 -07001706 skb->ignore_df = ip6_sk_ignore_df(sk);
Herbert Xu28a894532008-02-12 18:07:27 -08001707
Alexey Dobriyan4e3fd7a2011-11-21 03:39:03 +00001708 *final_dst = fl6->daddr;
Arnaldo Carvalho de Melocfe1fc72007-03-16 17:26:39 -03001709 __skb_pull(skb, skb_network_header_len(skb));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001710 if (opt && opt->opt_flen)
1711 ipv6_push_frag_opts(skb, opt, &proto);
1712 if (opt && opt->opt_nflen)
1713 ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst);
1714
Arnaldo Carvalho de Meloe2d1bca2007-04-10 20:46:21 -07001715 skb_push(skb, sizeof(struct ipv6hdr));
1716 skb_reset_network_header(skb);
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -07001717 hdr = ipv6_hdr(skb);
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +09001718
Vlad Yasevich64223982015-01-31 10:40:15 -05001719 ip6_flow_hdr(hdr, v6_cork->tclass,
Tom Herbertcb1ce2e2014-07-01 21:33:10 -07001720 ip6_make_flowlabel(net, skb, fl6->flowlabel,
Shaohua Lib3b56032017-12-20 12:10:21 -08001721 ip6_autoflowlabel(net, np), fl6));
Vlad Yasevich64223982015-01-31 10:40:15 -05001722 hdr->hop_limit = v6_cork->hop_limit;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001723 hdr->nexthdr = proto;
Alexey Dobriyan4e3fd7a2011-11-21 03:39:03 +00001724 hdr->saddr = fl6->saddr;
1725 hdr->daddr = *final_dst;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001726
Patrick McHardya2c20642006-01-08 22:37:26 -08001727 skb->priority = sk->sk_priority;
Laszlo Attila Toth4a19ec52008-01-30 19:08:16 -08001728 skb->mark = sk->sk_mark;
Patrick McHardya2c20642006-01-08 22:37:26 -08001729
Changli Gaod8d1f302010-06-10 23:31:35 -07001730 skb_dst_set(skb, dst_clone(&rt->dst));
Neil Hormanedf391f2009-04-27 02:45:02 -07001731 IP6_UPD_PO_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUT, skb->len);
David L Stevens14878f72007-09-16 16:52:35 -07001732 if (proto == IPPROTO_ICMPV6) {
Eric Dumazetadf30902009-06-02 05:19:30 +00001733 struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
David L Stevens14878f72007-09-16 16:52:35 -07001734
Hannes Frederic Sowa43a43b62014-03-31 20:14:10 +02001735 ICMP6MSGOUT_INC_STATS(net, idev, icmp6_hdr(skb)->icmp6_type);
1736 ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
David L Stevens14878f72007-09-16 16:52:35 -07001737 }
1738
Vlad Yasevich64223982015-01-31 10:40:15 -05001739 ip6_cork_release(cork, v6_cork);
1740out:
1741 return skb;
1742}
1743
1744int ip6_send_skb(struct sk_buff *skb)
1745{
1746 struct net *net = sock_net(skb->sk);
1747 struct rt6_info *rt = (struct rt6_info *)skb_dst(skb);
1748 int err;
1749
Eric W. Biederman33224b12015-10-07 16:48:46 -05001750 err = ip6_local_out(net, skb->sk, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001751 if (err) {
1752 if (err > 0)
Eric Dumazet6ce9e7b2009-09-02 18:05:33 -07001753 err = net_xmit_errno(err);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001754 if (err)
Vlad Yasevich64223982015-01-31 10:40:15 -05001755 IP6_INC_STATS(net, rt->rt6i_idev,
1756 IPSTATS_MIB_OUTDISCARDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001757 }
1758
Linus Torvalds1da177e2005-04-16 15:20:36 -07001759 return err;
Vlad Yasevich64223982015-01-31 10:40:15 -05001760}
1761
1762int ip6_push_pending_frames(struct sock *sk)
1763{
1764 struct sk_buff *skb;
1765
1766 skb = ip6_finish_skb(sk);
1767 if (!skb)
1768 return 0;
1769
1770 return ip6_send_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001771}
Chris Elstona495f832012-04-29 21:48:53 +00001772EXPORT_SYMBOL_GPL(ip6_push_pending_frames);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001773
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001774static void __ip6_flush_pending_frames(struct sock *sk,
Vlad Yasevich64223982015-01-31 10:40:15 -05001775 struct sk_buff_head *queue,
1776 struct inet_cork_full *cork,
1777 struct inet6_cork *v6_cork)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001778{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001779 struct sk_buff *skb;
1780
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001781 while ((skb = __skb_dequeue_tail(queue)) != NULL) {
Eric Dumazetadf30902009-06-02 05:19:30 +00001782 if (skb_dst(skb))
1783 IP6_INC_STATS(sock_net(sk), ip6_dst_idev(skb_dst(skb)),
YOSHIFUJI Hideakie1f522082007-09-11 11:31:43 +02001784 IPSTATS_MIB_OUTDISCARDS);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001785 kfree_skb(skb);
1786 }
1787
Vlad Yasevich64223982015-01-31 10:40:15 -05001788 ip6_cork_release(cork, v6_cork);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001789}
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001790
1791void ip6_flush_pending_frames(struct sock *sk)
1792{
Vlad Yasevich64223982015-01-31 10:40:15 -05001793 __ip6_flush_pending_frames(sk, &sk->sk_write_queue,
1794 &inet_sk(sk)->cork, &inet6_sk(sk)->cork);
Vlad Yasevich0bbe84a2015-01-31 10:40:14 -05001795}
Chris Elstona495f832012-04-29 21:48:53 +00001796EXPORT_SYMBOL_GPL(ip6_flush_pending_frames);
Vlad Yasevich64223982015-01-31 10:40:15 -05001797
1798struct sk_buff *ip6_make_skb(struct sock *sk,
1799 int getfrag(void *from, char *to, int offset,
1800 int len, int odd, struct sk_buff *skb),
1801 void *from, int length, int transhdrlen,
Wei Wang26879da2016-05-02 21:40:07 -07001802 struct ipcm6_cookie *ipc6, struct flowi6 *fl6,
Vlad Yasevich64223982015-01-31 10:40:15 -05001803 struct rt6_info *rt, unsigned int flags,
Wei Wang26879da2016-05-02 21:40:07 -07001804 const struct sockcm_cookie *sockc)
Vlad Yasevich64223982015-01-31 10:40:15 -05001805{
1806 struct inet_cork_full cork;
1807 struct inet6_cork v6_cork;
1808 struct sk_buff_head queue;
Wei Wang26879da2016-05-02 21:40:07 -07001809 int exthdrlen = (ipc6->opt ? ipc6->opt->opt_flen : 0);
Vlad Yasevich64223982015-01-31 10:40:15 -05001810 int err;
1811
1812 if (flags & MSG_PROBE)
1813 return NULL;
1814
1815 __skb_queue_head_init(&queue);
1816
1817 cork.base.flags = 0;
1818 cork.base.addr = 0;
1819 cork.base.opt = NULL;
Eric Dumazetc2ceff12018-01-11 22:31:18 -08001820 cork.base.dst = NULL;
Vlad Yasevich64223982015-01-31 10:40:15 -05001821 v6_cork.opt = NULL;
Wei Wang26879da2016-05-02 21:40:07 -07001822 err = ip6_setup_cork(sk, &cork, &v6_cork, ipc6, rt, fl6);
Eric Dumazetdde00c92018-01-10 03:45:49 -08001823 if (err) {
1824 ip6_cork_release(&cork, &v6_cork);
Vlad Yasevich64223982015-01-31 10:40:15 -05001825 return ERR_PTR(err);
Eric Dumazetdde00c92018-01-10 03:45:49 -08001826 }
Wei Wang26879da2016-05-02 21:40:07 -07001827 if (ipc6->dontfrag < 0)
1828 ipc6->dontfrag = inet6_sk(sk)->dontfrag;
Vlad Yasevich64223982015-01-31 10:40:15 -05001829
1830 err = __ip6_append_data(sk, fl6, &queue, &cork.base, &v6_cork,
1831 &current->task_frag, getfrag, from,
1832 length + exthdrlen, transhdrlen + exthdrlen,
Wei Wang26879da2016-05-02 21:40:07 -07001833 flags, ipc6, sockc);
Vlad Yasevich64223982015-01-31 10:40:15 -05001834 if (err) {
1835 __ip6_flush_pending_frames(sk, &queue, &cork, &v6_cork);
1836 return ERR_PTR(err);
1837 }
1838
1839 return __ip6_make_skb(sk, &queue, &cork, &v6_cork);
1840}