blob: 139ceb68bd3705b5bc4cedb0c5a1e39fa59fc6b8 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Extension Header handling for IPv6
3 * Linux INET6 implementation
4 *
5 * Authors:
6 * Pedro Roque <roque@di.fc.ul.pt>
7 * Andi Kleen <ak@muc.de>
8 * Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
9 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 * 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
16/* Changes:
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +090017 * yoshfuji : ensure not to overrun while parsing
Linus Torvalds1da177e2005-04-16 15:20:36 -070018 * tlv options.
19 * Mitsuru KANDA @USAGI and: Remove ipv6_parse_exthdrs().
20 * YOSHIFUJI Hideaki @USAGI Register inbound extension header
21 * handlers as inet6_protocol{}.
22 */
23
24#include <linux/errno.h>
25#include <linux/types.h>
26#include <linux/socket.h>
27#include <linux/sockios.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070028#include <linux/net.h>
29#include <linux/netdevice.h>
30#include <linux/in6.h>
31#include <linux/icmpv6.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090032#include <linux/slab.h>
Paul Gortmakerbc3b2d72011-07-15 11:47:34 -040033#include <linux/export.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034
Herbert Xu352e5122007-11-13 21:34:06 -080035#include <net/dst.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070036#include <net/sock.h>
37#include <net/snmp.h>
38
39#include <net/ipv6.h>
40#include <net/protocol.h>
41#include <net/transp_v6.h>
42#include <net/rawv6.h>
43#include <net/ndisc.h>
44#include <net/ip6_route.h>
45#include <net/addrconf.h>
Huw Davies2e532b72016-06-27 15:06:17 -040046#include <net/calipso.h>
Amerigo Wang07a93622012-10-29 16:23:10 +000047#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -070048#include <net/xfrm.h>
49#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070050
Fabian Frederickce256982014-10-27 19:12:58 +010051#include <linux/uaccess.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070052
53/*
54 * Parsing tlv encoded headers.
55 *
Eric Dumazeta50feda2012-05-18 18:57:34 +000056 * Parsing function "func" returns true, if parsing succeed
57 * and false, if it failed.
Linus Torvalds1da177e2005-04-16 15:20:36 -070058 * It MUST NOT touch skb->h.
59 */
60
61struct tlvtype_proc {
62 int type;
Eric Dumazeta50feda2012-05-18 18:57:34 +000063 bool (*func)(struct sk_buff *skb, int offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -070064};
65
66/*********************
67 Generic functions
68 *********************/
69
70/* An unknown option is detected, decide what to do */
71
Eric Dumazeta50feda2012-05-18 18:57:34 +000072static bool ip6_tlvopt_unknown(struct sk_buff *skb, int optoff)
Linus Torvalds1da177e2005-04-16 15:20:36 -070073{
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -070074 switch ((skb_network_header(skb)[optoff] & 0xC0) >> 6) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070075 case 0: /* ignore */
Eric Dumazeta50feda2012-05-18 18:57:34 +000076 return true;
Linus Torvalds1da177e2005-04-16 15:20:36 -070077
78 case 1: /* drop packet */
79 break;
80
81 case 3: /* Send ICMP if not a multicast address and drop packet */
82 /* Actually, it is redundant check. icmp_send
83 will recheck in any case.
84 */
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -070085 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr))
Linus Torvalds1da177e2005-04-16 15:20:36 -070086 break;
87 case 2: /* send ICMP PARM PROB regardless and drop packet */
88 icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff);
Eric Dumazeta50feda2012-05-18 18:57:34 +000089 return false;
Stephen Hemminger3ff50b72007-04-20 17:09:22 -070090 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070091
92 kfree_skb(skb);
Eric Dumazeta50feda2012-05-18 18:57:34 +000093 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -070094}
95
96/* Parse tlv encoded option header (hop-by-hop or destination) */
97
Eric Dumazeta50feda2012-05-18 18:57:34 +000098static bool ip6_parse_tlv(const struct tlvtype_proc *procs, struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -070099{
Eric Dumazeta50feda2012-05-18 18:57:34 +0000100 const struct tlvtype_proc *curr;
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700101 const unsigned char *nh = skb_network_header(skb);
Arnaldo Carvalho de Melocfe1fc72007-03-16 17:26:39 -0300102 int off = skb_network_header_len(skb);
Arnaldo Carvalho de Melo9c702202007-04-25 18:04:18 -0700103 int len = (skb_transport_header(skb)[1] + 1) << 3;
Eldad Zack9b905fe2012-05-20 01:59:33 +0000104 int padlen = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105
Arnaldo Carvalho de Meloea2ae172007-04-25 17:55:53 -0700106 if (skb_transport_offset(skb) + len > skb_headlen(skb))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 goto bad;
108
109 off += 2;
110 len -= 2;
111
112 while (len > 0) {
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700113 int optlen = nh[off + 1] + 2;
Eldad Zackc1412fc2012-04-12 17:36:17 -0400114 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700116 switch (nh[off]) {
Eldad Zack1de5a712012-05-17 06:00:25 +0000117 case IPV6_TLV_PAD1:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 optlen = 1;
Eldad Zack9b905fe2012-05-20 01:59:33 +0000119 padlen++;
120 if (padlen > 7)
121 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122 break;
123
124 case IPV6_TLV_PADN:
Eldad Zackc1412fc2012-04-12 17:36:17 -0400125 /* RFC 2460 states that the purpose of PadN is
126 * to align the containing header to multiples
127 * of 8. 7 is therefore the highest valid value.
128 * See also RFC 4942, Section 2.1.9.5.
129 */
Eldad Zack9b905fe2012-05-20 01:59:33 +0000130 padlen += optlen;
131 if (padlen > 7)
Eldad Zackc1412fc2012-04-12 17:36:17 -0400132 goto bad;
133 /* RFC 4942 recommends receiving hosts to
134 * actively check PadN payload to contain
135 * only zeroes.
136 */
137 for (i = 2; i < optlen; i++) {
138 if (nh[off + i] != 0)
139 goto bad;
140 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141 break;
142
143 default: /* Other TLV code so scan list */
144 if (optlen > len)
145 goto bad;
Ian Morris67ba4152014-08-24 21:53:10 +0100146 for (curr = procs; curr->type >= 0; curr++) {
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700147 if (curr->type == nh[off]) {
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900148 /* type specific length/alignment
149 checks will be performed in the
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150 func(). */
Eric Dumazeta50feda2012-05-18 18:57:34 +0000151 if (curr->func(skb, off) == false)
152 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 break;
154 }
155 }
156 if (curr->type < 0) {
Herbert Xue5bbef22007-10-15 12:50:28 -0700157 if (ip6_tlvopt_unknown(skb, off) == 0)
Eric Dumazeta50feda2012-05-18 18:57:34 +0000158 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159 }
Eldad Zack9b905fe2012-05-20 01:59:33 +0000160 padlen = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161 break;
162 }
163 off += optlen;
164 len -= optlen;
165 }
Eldad Zack9b905fe2012-05-20 01:59:33 +0000166
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167 if (len == 0)
Eric Dumazeta50feda2012-05-18 18:57:34 +0000168 return true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169bad:
170 kfree_skb(skb);
Eric Dumazeta50feda2012-05-18 18:57:34 +0000171 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172}
173
174/*****************************
175 Destination options header.
176 *****************************/
177
Amerigo Wang07a93622012-10-29 16:23:10 +0000178#if IS_ENABLED(CONFIG_IPV6_MIP6)
Eric Dumazeta50feda2012-05-18 18:57:34 +0000179static bool ipv6_dest_hao(struct sk_buff *skb, int optoff)
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700180{
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700181 struct ipv6_destopt_hao *hao;
182 struct inet6_skb_parm *opt = IP6CB(skb);
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700183 struct ipv6hdr *ipv6h = ipv6_hdr(skb);
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700184 struct in6_addr tmp_addr;
185 int ret;
186
187 if (opt->dsthao) {
Joe Perchesba7a46f2014-11-11 10:59:17 -0800188 net_dbg_ratelimited("hao duplicated\n");
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700189 goto discard;
190 }
191 opt->dsthao = opt->dst1;
192 opt->dst1 = 0;
193
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700194 hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff);
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700195
196 if (hao->length != 16) {
Joe Perchesba7a46f2014-11-11 10:59:17 -0800197 net_dbg_ratelimited("hao invalid option length = %d\n",
198 hao->length);
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700199 goto discard;
200 }
201
202 if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) {
Joe Perchesba7a46f2014-11-11 10:59:17 -0800203 net_dbg_ratelimited("hao is not an unicast addr: %pI6\n",
204 &hao->addr);
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700205 goto discard;
206 }
207
208 ret = xfrm6_input_addr(skb, (xfrm_address_t *)&ipv6h->daddr,
209 (xfrm_address_t *)&hao->addr, IPPROTO_DSTOPTS);
210 if (unlikely(ret < 0))
211 goto discard;
212
213 if (skb_cloned(skb)) {
Herbert Xu65c88462007-10-15 01:29:10 -0700214 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700215 goto discard;
216
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700217 /* update all variable using below by copied skbuff */
Herbert Xu65c88462007-10-15 01:29:10 -0700218 hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) +
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700219 optoff);
Herbert Xu65c88462007-10-15 01:29:10 -0700220 ipv6h = ipv6_hdr(skb);
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700221 }
222
223 if (skb->ip_summed == CHECKSUM_COMPLETE)
224 skb->ip_summed = CHECKSUM_NONE;
225
Alexey Dobriyan4e3fd7a2011-11-21 03:39:03 +0000226 tmp_addr = ipv6h->saddr;
227 ipv6h->saddr = hao->addr;
228 hao->addr = tmp_addr;
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700229
Eric Dumazetb7aa0bf2007-04-19 16:16:32 -0700230 if (skb->tstamp.tv64 == 0)
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700231 __net_timestamp(skb);
232
Eric Dumazeta50feda2012-05-18 18:57:34 +0000233 return true;
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700234
235 discard:
236 kfree_skb(skb);
Eric Dumazeta50feda2012-05-18 18:57:34 +0000237 return false;
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700238}
239#endif
240
Eric Dumazeta50feda2012-05-18 18:57:34 +0000241static const struct tlvtype_proc tlvprocdestopt_lst[] = {
Amerigo Wang07a93622012-10-29 16:23:10 +0000242#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700243 {
244 .type = IPV6_TLV_HAO,
245 .func = ipv6_dest_hao,
246 },
247#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248 {-1, NULL}
249};
250
Herbert Xue5bbef22007-10-15 12:50:28 -0700251static int ipv6_destopt_rcv(struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 struct inet6_skb_parm *opt = IP6CB(skb);
Amerigo Wang07a93622012-10-29 16:23:10 +0000254#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700255 __u16 dstbuf;
256#endif
Eric Dumazet897dc802011-07-28 04:00:35 +0000257 struct dst_entry *dst = skb_dst(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258
Arnaldo Carvalho de Meloea2ae172007-04-25 17:55:53 -0700259 if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) ||
260 !pskb_may_pull(skb, (skb_transport_offset(skb) +
Arnaldo Carvalho de Melo9c702202007-04-25 18:04:18 -0700261 ((skb_transport_header(skb)[1] + 1) << 3)))) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700262 __IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
263 IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264 kfree_skb(skb);
265 return -1;
266 }
267
Arnaldo Carvalho de Melocfe1fc72007-03-16 17:26:39 -0300268 opt->lastopt = opt->dst1 = skb_network_header_len(skb);
Amerigo Wang07a93622012-10-29 16:23:10 +0000269#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700270 dstbuf = opt->dst1;
271#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272
Herbert Xue5bbef22007-10-15 12:50:28 -0700273 if (ip6_parse_tlv(tlvprocdestopt_lst, skb)) {
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700274 skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3;
Masahide NAKAMURAdc435e62006-08-31 15:18:49 -0700275 opt = IP6CB(skb);
Amerigo Wang07a93622012-10-29 16:23:10 +0000276#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700277 opt->nhoff = dstbuf;
278#else
Patrick McHardy951dbc82006-01-06 23:02:34 -0800279 opt->nhoff = opt->dst1;
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700280#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281 return 1;
282 }
283
Eric Dumazet1d015502016-04-27 16:44:40 -0700284 __IP6_INC_STATS(dev_net(dst->dev),
285 ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286 return -1;
287}
288
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289/********************************
290 Routing header.
291 ********************************/
292
Eric Dumazetf6bc7d92010-06-14 04:39:27 +0000293/* called with rcu_read_lock() */
Herbert Xue5bbef22007-10-15 12:50:28 -0700294static int ipv6_rthdr_rcv(struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700296 struct inet6_skb_parm *opt = IP6CB(skb);
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700297 struct in6_addr *addr = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298 struct in6_addr daddr;
YOSHIFUJI Hideaki0bcbc922007-04-24 14:58:30 -0700299 struct inet6_dev *idev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300 int n, i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 struct ipv6_rt_hdr *hdr;
302 struct rt0_hdr *rthdr;
Denis V. Lunev483a47d2008-10-08 11:09:27 -0700303 struct net *net = dev_net(skb->dev);
304 int accept_source_route = net->ipv6.devconf_all->accept_source_route;
YOSHIFUJI Hideaki0bcbc922007-04-24 14:58:30 -0700305
Eric Dumazetf6bc7d92010-06-14 04:39:27 +0000306 idev = __in6_dev_get(skb->dev);
307 if (idev && accept_source_route > idev->cnf.accept_source_route)
308 accept_source_route = idev->cnf.accept_source_route;
YOSHIFUJI Hideaki0bcbc922007-04-24 14:58:30 -0700309
Arnaldo Carvalho de Meloea2ae172007-04-25 17:55:53 -0700310 if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) ||
311 !pskb_may_pull(skb, (skb_transport_offset(skb) +
Arnaldo Carvalho de Melo9c702202007-04-25 18:04:18 -0700312 ((skb_transport_header(skb)[1] + 1) << 3)))) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700313 __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
314 IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315 kfree_skb(skb);
316 return -1;
317 }
318
Arnaldo Carvalho de Melo9c702202007-04-25 18:04:18 -0700319 hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700321 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) ||
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322 skb->pkt_type != PACKET_HOST) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700323 __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
324 IPSTATS_MIB_INADDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 kfree_skb(skb);
326 return -1;
327 }
328
329looped_back:
330 if (hdr->segments_left == 0) {
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700331 switch (hdr->type) {
Amerigo Wang07a93622012-10-29 16:23:10 +0000332#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700333 case IPV6_SRCRT_TYPE_2:
334 /* Silently discard type 2 header unless it was
335 * processed by own
336 */
337 if (!addr) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700338 __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
339 IPSTATS_MIB_INADDRERRORS);
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700340 kfree_skb(skb);
341 return -1;
342 }
343 break;
344#endif
345 default:
346 break;
347 }
348
Arnaldo Carvalho de Melocfe1fc72007-03-16 17:26:39 -0300349 opt->lastopt = opt->srcrt = skb_network_header_len(skb);
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700350 skb->transport_header += (hdr->hdrlen + 1) << 3;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700351 opt->dst0 = opt->dst1;
352 opt->dst1 = 0;
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700353 opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 return 1;
355 }
356
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700357 switch (hdr->type) {
Amerigo Wang07a93622012-10-29 16:23:10 +0000358#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700359 case IPV6_SRCRT_TYPE_2:
YOSHIFUJI Hideakic382bb92007-07-10 22:47:58 -0700360 if (accept_source_route < 0)
361 goto unknown_rh;
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700362 /* Silently discard invalid RTH type 2 */
363 if (hdr->hdrlen != 2 || hdr->segments_left != 1) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700364 __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
365 IPSTATS_MIB_INHDRERRORS);
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700366 kfree_skb(skb);
367 return -1;
368 }
369 break;
370#endif
YOSHIFUJI Hideakic382bb92007-07-10 22:47:58 -0700371 default:
372 goto unknown_rh;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374
375 /*
376 * This is the routing header forwarding algorithm from
377 * RFC 2460, page 16.
378 */
379
380 n = hdr->hdrlen >> 1;
381
382 if (hdr->segments_left > n) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700383 __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
384 IPSTATS_MIB_INHDRERRORS);
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700385 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
386 ((&hdr->segments_left) -
387 skb_network_header(skb)));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 return -1;
389 }
390
391 /* We are about to mangle packet header. Be careful!
392 Do not damage packets queued somewhere.
393 */
394 if (skb_cloned(skb)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395 /* the copy is a forwarded packet */
Herbert Xu65c88462007-10-15 01:29:10 -0700396 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700397 __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
398 IPSTATS_MIB_OUTDISCARDS);
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900399 kfree_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 return -1;
401 }
Herbert Xu65c88462007-10-15 01:29:10 -0700402 hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700403 }
404
Patrick McHardy84fa7932006-08-29 16:44:56 -0700405 if (skb->ip_summed == CHECKSUM_COMPLETE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700406 skb->ip_summed = CHECKSUM_NONE;
407
408 i = n - --hdr->segments_left;
409
410 rthdr = (struct rt0_hdr *) hdr;
411 addr = rthdr->addr;
412 addr += i - 1;
413
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700414 switch (hdr->type) {
Amerigo Wang07a93622012-10-29 16:23:10 +0000415#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700416 case IPV6_SRCRT_TYPE_2:
417 if (xfrm6_input_addr(skb, (xfrm_address_t *)addr,
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700418 (xfrm_address_t *)&ipv6_hdr(skb)->saddr,
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700419 IPPROTO_ROUTING) < 0) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700420 __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
421 IPSTATS_MIB_INADDRERRORS);
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700422 kfree_skb(skb);
423 return -1;
424 }
Eric Dumazetadf30902009-06-02 05:19:30 +0000425 if (!ipv6_chk_home_addr(dev_net(skb_dst(skb)->dev), addr)) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700426 __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
427 IPSTATS_MIB_INADDRERRORS);
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700428 kfree_skb(skb);
429 return -1;
430 }
431 break;
432#endif
433 default:
434 break;
435 }
436
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437 if (ipv6_addr_is_multicast(addr)) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700438 __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
439 IPSTATS_MIB_INADDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440 kfree_skb(skb);
441 return -1;
442 }
443
Alexey Dobriyan4e3fd7a2011-11-21 03:39:03 +0000444 daddr = *addr;
445 *addr = ipv6_hdr(skb)->daddr;
446 ipv6_hdr(skb)->daddr = daddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447
Eric Dumazetadf30902009-06-02 05:19:30 +0000448 skb_dst_drop(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449 ip6_route_input(skb);
Eric Dumazetadf30902009-06-02 05:19:30 +0000450 if (skb_dst(skb)->error) {
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700451 skb_push(skb, skb->data - skb_network_header(skb));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452 dst_input(skb);
453 return -1;
454 }
455
Eric Dumazetadf30902009-06-02 05:19:30 +0000456 if (skb_dst(skb)->dev->flags&IFF_LOOPBACK) {
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700457 if (ipv6_hdr(skb)->hop_limit <= 1) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700458 __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
459 IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460 icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT,
Alexey Dobriyan3ffe5332010-02-18 08:25:24 +0000461 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700462 kfree_skb(skb);
463 return -1;
464 }
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700465 ipv6_hdr(skb)->hop_limit--;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 goto looped_back;
467 }
468
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700469 skb_push(skb, skb->data - skb_network_header(skb));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700470 dst_input(skb);
471 return -1;
YOSHIFUJI Hideakic382bb92007-07-10 22:47:58 -0700472
473unknown_rh:
Eric Dumazet1d015502016-04-27 16:44:40 -0700474 __IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS);
YOSHIFUJI Hideakic382bb92007-07-10 22:47:58 -0700475 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
476 (&hdr->type) - skb_network_header(skb));
477 return -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478}
479
Alexey Dobriyan41135cc2009-09-14 12:22:28 +0000480static const struct inet6_protocol rthdr_protocol = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 .handler = ipv6_rthdr_rcv,
Vlad Yasevich2207afc2012-11-15 08:49:19 +0000482 .flags = INET6_PROTO_NOPOLICY,
Vlad Yasevich8ca896c2012-11-15 08:49:13 +0000483};
484
Alexey Dobriyan41135cc2009-09-14 12:22:28 +0000485static const struct inet6_protocol destopt_protocol = {
Daniel Lezcano248b2382007-12-11 02:23:54 -0800486 .handler = ipv6_destopt_rcv,
Vlad Yasevich2207afc2012-11-15 08:49:19 +0000487 .flags = INET6_PROTO_NOPOLICY,
Vlad Yasevich8ca896c2012-11-15 08:49:13 +0000488};
489
Alexey Dobriyan41135cc2009-09-14 12:22:28 +0000490static const struct inet6_protocol nodata_protocol = {
Daniel Lezcano248b2382007-12-11 02:23:54 -0800491 .handler = dst_discard,
492 .flags = INET6_PROTO_NOPOLICY,
493};
494
495int __init ipv6_exthdrs_init(void)
496{
497 int ret;
498
Vlad Yasevich33362882012-11-15 08:49:15 +0000499 ret = inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING);
500 if (ret)
Vlad Yasevichc6b641a2012-11-15 08:49:22 +0000501 goto out;
Vlad Yasevich33362882012-11-15 08:49:15 +0000502
Daniel Lezcano248b2382007-12-11 02:23:54 -0800503 ret = inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
504 if (ret)
505 goto out_rthdr;
506
507 ret = inet6_add_protocol(&nodata_protocol, IPPROTO_NONE);
508 if (ret)
509 goto out_destopt;
510
511out:
512 return ret;
Daniel Lezcano248b2382007-12-11 02:23:54 -0800513out_destopt:
514 inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
Vlad Yasevich33362882012-11-15 08:49:15 +0000515out_rthdr:
516 inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING);
Daniel Lezcano248b2382007-12-11 02:23:54 -0800517 goto out;
518};
519
520void ipv6_exthdrs_exit(void)
521{
522 inet6_del_protocol(&nodata_protocol, IPPROTO_NONE);
523 inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
524 inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING);
525}
526
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527/**********************************
528 Hop-by-hop options.
529 **********************************/
530
YOSHIFUJI Hideakie76b2b22007-05-09 14:01:59 -0700531/*
Eric Dumazetadf30902009-06-02 05:19:30 +0000532 * Note: we cannot rely on skb_dst(skb) before we assign it in ip6_route_input().
YOSHIFUJI Hideakie76b2b22007-05-09 14:01:59 -0700533 */
534static inline struct inet6_dev *ipv6_skb_idev(struct sk_buff *skb)
535{
Eric Dumazetadf30902009-06-02 05:19:30 +0000536 return skb_dst(skb) ? ip6_dst_idev(skb_dst(skb)) : __in6_dev_get(skb->dev);
YOSHIFUJI Hideakie76b2b22007-05-09 14:01:59 -0700537}
538
David S. Miller2570a4f2010-01-13 17:27:37 -0800539static inline struct net *ipv6_skb_net(struct sk_buff *skb)
540{
541 return skb_dst(skb) ? dev_net(skb_dst(skb)->dev) : dev_net(skb->dev);
542}
543
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544/* Router Alert as of RFC 2711 */
545
Eric Dumazeta50feda2012-05-18 18:57:34 +0000546static bool ipv6_hop_ra(struct sk_buff *skb, int optoff)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547{
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700548 const unsigned char *nh = skb_network_header(skb);
Masahide NAKAMURAa80ff032006-08-23 19:19:50 -0700549
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700550 if (nh[optoff + 1] == 2) {
YOSHIFUJI Hideaki / 吉藤英明dd3332b2013-01-13 05:02:45 +0000551 IP6CB(skb)->flags |= IP6SKB_ROUTERALERT;
552 memcpy(&IP6CB(skb)->ra, nh + optoff + 2, sizeof(IP6CB(skb)->ra));
Eric Dumazeta50feda2012-05-18 18:57:34 +0000553 return true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554 }
Joe Perchesba7a46f2014-11-11 10:59:17 -0800555 net_dbg_ratelimited("ipv6_hop_ra: wrong RA length %d\n",
556 nh[optoff + 1]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557 kfree_skb(skb);
Eric Dumazeta50feda2012-05-18 18:57:34 +0000558 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559}
560
561/* Jumbo payload */
562
Eric Dumazeta50feda2012-05-18 18:57:34 +0000563static bool ipv6_hop_jumbo(struct sk_buff *skb, int optoff)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564{
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700565 const unsigned char *nh = skb_network_header(skb);
David S. Miller2570a4f2010-01-13 17:27:37 -0800566 struct net *net = ipv6_skb_net(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567 u32 pkt_len;
568
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700569 if (nh[optoff + 1] != 4 || (optoff & 3) != 2) {
Joe Perchesba7a46f2014-11-11 10:59:17 -0800570 net_dbg_ratelimited("ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n",
571 nh[optoff+1]);
Eric Dumazet1d015502016-04-27 16:44:40 -0700572 __IP6_INC_STATS(net, ipv6_skb_idev(skb),
573 IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574 goto drop;
575 }
576
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700577 pkt_len = ntohl(*(__be32 *)(nh + optoff + 2));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700578 if (pkt_len <= IPV6_MAXPLEN) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700579 __IP6_INC_STATS(net, ipv6_skb_idev(skb),
580 IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2);
Eric Dumazeta50feda2012-05-18 18:57:34 +0000582 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583 }
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700584 if (ipv6_hdr(skb)->payload_len) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700585 __IP6_INC_STATS(net, ipv6_skb_idev(skb),
586 IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff);
Eric Dumazeta50feda2012-05-18 18:57:34 +0000588 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589 }
590
591 if (pkt_len > skb->len - sizeof(struct ipv6hdr)) {
Eric Dumazet1d015502016-04-27 16:44:40 -0700592 __IP6_INC_STATS(net, ipv6_skb_idev(skb),
593 IPSTATS_MIB_INTRUNCATEDPKTS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700594 goto drop;
595 }
Stephen Hemminger42ca89c2005-09-08 12:57:43 -0700596
597 if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr)))
598 goto drop;
599
Eric Dumazeta50feda2012-05-18 18:57:34 +0000600 return true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601
602drop:
603 kfree_skb(skb);
Eric Dumazeta50feda2012-05-18 18:57:34 +0000604 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605}
606
Huw Davies2e532b72016-06-27 15:06:17 -0400607/* CALIPSO RFC 5570 */
608
609static bool ipv6_hop_calipso(struct sk_buff *skb, int optoff)
610{
611 const unsigned char *nh = skb_network_header(skb);
612
613 if (nh[optoff + 1] < 8)
614 goto drop;
615
616 if (nh[optoff + 6] * 4 + 8 > nh[optoff + 1])
617 goto drop;
618
619 if (!calipso_validate(skb, nh + optoff))
620 goto drop;
621
622 return true;
623
624drop:
625 kfree_skb(skb);
626 return false;
627}
628
Eric Dumazeta50feda2012-05-18 18:57:34 +0000629static const struct tlvtype_proc tlvprochopopt_lst[] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630 {
631 .type = IPV6_TLV_ROUTERALERT,
632 .func = ipv6_hop_ra,
633 },
634 {
635 .type = IPV6_TLV_JUMBO,
636 .func = ipv6_hop_jumbo,
637 },
Huw Davies2e532b72016-06-27 15:06:17 -0400638 {
639 .type = IPV6_TLV_CALIPSO,
640 .func = ipv6_hop_calipso,
641 },
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642 { -1, }
643};
644
Herbert Xue5bbef22007-10-15 12:50:28 -0700645int ipv6_parse_hopopts(struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700646{
Patrick McHardy951dbc82006-01-06 23:02:34 -0800647 struct inet6_skb_parm *opt = IP6CB(skb);
648
YOSHIFUJI Hideakiec670092006-04-18 14:46:26 -0700649 /*
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700650 * skb_network_header(skb) is equal to skb->data, and
Arnaldo Carvalho de Melocfe1fc72007-03-16 17:26:39 -0300651 * skb_network_header_len(skb) is always equal to
YOSHIFUJI Hideakiec670092006-04-18 14:46:26 -0700652 * sizeof(struct ipv6hdr) by definition of
653 * hop-by-hop options.
654 */
655 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + 8) ||
Arnaldo Carvalho de Melo9c702202007-04-25 18:04:18 -0700656 !pskb_may_pull(skb, (sizeof(struct ipv6hdr) +
657 ((skb_transport_header(skb)[1] + 1) << 3)))) {
YOSHIFUJI Hideakiec670092006-04-18 14:46:26 -0700658 kfree_skb(skb);
659 return -1;
660 }
661
Florian Westphal8b58a392015-07-08 23:32:12 +0200662 opt->flags |= IP6SKB_HOPBYHOP;
Herbert Xue5bbef22007-10-15 12:50:28 -0700663 if (ip6_parse_tlv(tlvprochopopt_lst, skb)) {
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700664 skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3;
Masahide NAKAMURAdc435e62006-08-31 15:18:49 -0700665 opt = IP6CB(skb);
Patrick McHardy951dbc82006-01-06 23:02:34 -0800666 opt->nhoff = sizeof(struct ipv6hdr);
YOSHIFUJI Hideakib8097392006-04-18 14:48:45 -0700667 return 1;
Patrick McHardy951dbc82006-01-06 23:02:34 -0800668 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669 return -1;
670}
671
672/*
673 * Creating outbound headers.
674 *
675 * "build" functions work when skb is filled from head to tail (datagram)
676 * "push" functions work when headers are added from tail to head (tcp)
677 *
678 * In both cases we assume, that caller reserved enough room
679 * for headers.
680 */
681
682static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto,
683 struct ipv6_rt_hdr *opt,
684 struct in6_addr **addr_p)
685{
686 struct rt0_hdr *phdr, *ihdr;
687 int hops;
688
689 ihdr = (struct rt0_hdr *) opt;
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900690
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691 phdr = (struct rt0_hdr *) skb_push(skb, (ihdr->rt_hdr.hdrlen + 1) << 3);
692 memcpy(phdr, ihdr, sizeof(struct rt0_hdr));
693
694 hops = ihdr->rt_hdr.hdrlen >> 1;
695
696 if (hops > 1)
697 memcpy(phdr->addr, ihdr->addr + 1,
698 (hops - 1) * sizeof(struct in6_addr));
699
Alexey Dobriyan4e3fd7a2011-11-21 03:39:03 +0000700 phdr->addr[hops - 1] = **addr_p;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701 *addr_p = ihdr->addr;
702
703 phdr->rt_hdr.nexthdr = *proto;
704 *proto = NEXTHDR_ROUTING;
705}
706
707static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt)
708{
709 struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)skb_push(skb, ipv6_optlen(opt));
710
711 memcpy(h, opt, ipv6_optlen(opt));
712 h->nexthdr = *proto;
713 *proto = type;
714}
715
716void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
717 u8 *proto,
718 struct in6_addr **daddr)
719{
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900720 if (opt->srcrt) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700721 ipv6_push_rthdr(skb, proto, opt->srcrt, daddr);
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900722 /*
723 * IPV6_RTHDRDSTOPTS is ignored
724 * unless IPV6_RTHDR is set (RFC3542).
725 */
726 if (opt->dst0opt)
727 ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst0opt);
728 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729 if (opt->hopopt)
730 ipv6_push_exthdr(skb, proto, NEXTHDR_HOP, opt->hopopt);
731}
YOSHIFUJI Hideaki71590392007-02-22 22:05:40 +0900732EXPORT_SYMBOL(ipv6_push_nfrag_opts);
733
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, u8 *proto)
735{
736 if (opt->dst1opt)
737 ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst1opt);
738}
739
740struct ipv6_txoptions *
741ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt)
742{
743 struct ipv6_txoptions *opt2;
744
745 opt2 = sock_kmalloc(sk, opt->tot_len, GFP_ATOMIC);
746 if (opt2) {
Eldad Zackac3c8172012-04-01 07:49:04 +0000747 long dif = (char *)opt2 - (char *)opt;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748 memcpy(opt2, opt, opt->tot_len);
749 if (opt2->hopopt)
Eldad Zackac3c8172012-04-01 07:49:04 +0000750 *((char **)&opt2->hopopt) += dif;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700751 if (opt2->dst0opt)
Eldad Zackac3c8172012-04-01 07:49:04 +0000752 *((char **)&opt2->dst0opt) += dif;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753 if (opt2->dst1opt)
Eldad Zackac3c8172012-04-01 07:49:04 +0000754 *((char **)&opt2->dst1opt) += dif;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755 if (opt2->srcrt)
Eldad Zackac3c8172012-04-01 07:49:04 +0000756 *((char **)&opt2->srcrt) += dif;
Eric Dumazet45f6fad2015-11-29 19:37:57 -0800757 atomic_set(&opt2->refcnt, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700758 }
759 return opt2;
760}
Arnaldo Carvalho de Melo3cf3dc62005-12-13 23:23:20 -0800761EXPORT_SYMBOL_GPL(ipv6_dup_options);
762
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900763static int ipv6_renew_option(void *ohdr,
764 struct ipv6_opt_hdr __user *newopt, int newoptlen,
765 int inherit,
766 struct ipv6_opt_hdr **hdr,
767 char **p)
768{
769 if (inherit) {
770 if (ohdr) {
771 memcpy(*p, ohdr, ipv6_optlen((struct ipv6_opt_hdr *)ohdr));
772 *hdr = (struct ipv6_opt_hdr *)*p;
Joe Perchese3192692012-06-03 17:41:40 +0000773 *p += CMSG_ALIGN(ipv6_optlen(*hdr));
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900774 }
775 } else {
776 if (newopt) {
777 if (copy_from_user(*p, newopt, newoptlen))
778 return -EFAULT;
779 *hdr = (struct ipv6_opt_hdr *)*p;
Joe Perchese3192692012-06-03 17:41:40 +0000780 if (ipv6_optlen(*hdr) > newoptlen)
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900781 return -EINVAL;
782 *p += CMSG_ALIGN(newoptlen);
783 }
784 }
785 return 0;
786}
787
Huw Daviese67ae212016-06-27 15:02:50 -0400788/**
789 * ipv6_renew_options - replace a specific ext hdr with a new one.
790 *
791 * @sk: sock from which to allocate memory
792 * @opt: original options
793 * @newtype: option type to replace in @opt
794 * @newopt: new option of type @newtype to replace (user-mem)
795 * @newoptlen: length of @newopt
796 *
797 * Returns a new set of options which is a copy of @opt with the
798 * option type @newtype replaced with @newopt.
799 *
800 * @opt may be NULL, in which case a new set of options is returned
801 * containing just @newopt.
802 *
803 * @newopt may be NULL, in which case the specified option type is
804 * not copied into the new set of options.
805 *
806 * The new set of options is allocated from the socket option memory
807 * buffer of @sk.
808 */
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900809struct ipv6_txoptions *
810ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt,
811 int newtype,
812 struct ipv6_opt_hdr __user *newopt, int newoptlen)
813{
814 int tot_len = 0;
815 char *p;
816 struct ipv6_txoptions *opt2;
817 int err;
818
YOSHIFUJI Hideaki99c7bc02006-08-31 14:52:17 -0700819 if (opt) {
820 if (newtype != IPV6_HOPOPTS && opt->hopopt)
821 tot_len += CMSG_ALIGN(ipv6_optlen(opt->hopopt));
822 if (newtype != IPV6_RTHDRDSTOPTS && opt->dst0opt)
823 tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst0opt));
824 if (newtype != IPV6_RTHDR && opt->srcrt)
825 tot_len += CMSG_ALIGN(ipv6_optlen(opt->srcrt));
826 if (newtype != IPV6_DSTOPTS && opt->dst1opt)
827 tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst1opt));
828 }
829
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900830 if (newopt && newoptlen)
831 tot_len += CMSG_ALIGN(newoptlen);
832
833 if (!tot_len)
834 return NULL;
835
YOSHIFUJI Hideaki8b8aa4b2005-11-20 12:18:17 +0900836 tot_len += sizeof(*opt2);
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900837 opt2 = sock_kmalloc(sk, tot_len, GFP_ATOMIC);
838 if (!opt2)
839 return ERR_PTR(-ENOBUFS);
840
841 memset(opt2, 0, tot_len);
Eric Dumazet45f6fad2015-11-29 19:37:57 -0800842 atomic_set(&opt2->refcnt, 1);
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900843 opt2->tot_len = tot_len;
844 p = (char *)(opt2 + 1);
845
YOSHIFUJI Hideaki99c7bc02006-08-31 14:52:17 -0700846 err = ipv6_renew_option(opt ? opt->hopopt : NULL, newopt, newoptlen,
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900847 newtype != IPV6_HOPOPTS,
848 &opt2->hopopt, &p);
849 if (err)
850 goto out;
851
YOSHIFUJI Hideaki99c7bc02006-08-31 14:52:17 -0700852 err = ipv6_renew_option(opt ? opt->dst0opt : NULL, newopt, newoptlen,
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900853 newtype != IPV6_RTHDRDSTOPTS,
854 &opt2->dst0opt, &p);
855 if (err)
856 goto out;
857
YOSHIFUJI Hideaki99c7bc02006-08-31 14:52:17 -0700858 err = ipv6_renew_option(opt ? opt->srcrt : NULL, newopt, newoptlen,
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900859 newtype != IPV6_RTHDR,
YOSHIFUJI Hideaki99c7bc02006-08-31 14:52:17 -0700860 (struct ipv6_opt_hdr **)&opt2->srcrt, &p);
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900861 if (err)
862 goto out;
863
YOSHIFUJI Hideaki99c7bc02006-08-31 14:52:17 -0700864 err = ipv6_renew_option(opt ? opt->dst1opt : NULL, newopt, newoptlen,
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900865 newtype != IPV6_DSTOPTS,
866 &opt2->dst1opt, &p);
867 if (err)
868 goto out;
869
870 opt2->opt_nflen = (opt2->hopopt ? ipv6_optlen(opt2->hopopt) : 0) +
871 (opt2->dst0opt ? ipv6_optlen(opt2->dst0opt) : 0) +
872 (opt2->srcrt ? ipv6_optlen(opt2->srcrt) : 0);
873 opt2->opt_flen = (opt2->dst1opt ? ipv6_optlen(opt2->dst1opt) : 0);
874
875 return opt2;
876out:
YOSHIFUJI Hideaki8b8aa4b2005-11-20 12:18:17 +0900877 sock_kfree_s(sk, opt2, opt2->tot_len);
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900878 return ERR_PTR(err);
879}
880
Huw Daviese67ae212016-06-27 15:02:50 -0400881/**
882 * ipv6_renew_options_kern - replace a specific ext hdr with a new one.
883 *
884 * @sk: sock from which to allocate memory
885 * @opt: original options
886 * @newtype: option type to replace in @opt
887 * @newopt: new option of type @newtype to replace (kernel-mem)
888 * @newoptlen: length of @newopt
889 *
890 * See ipv6_renew_options(). The difference is that @newopt is
891 * kernel memory, rather than user memory.
892 */
893struct ipv6_txoptions *
894ipv6_renew_options_kern(struct sock *sk, struct ipv6_txoptions *opt,
895 int newtype, struct ipv6_opt_hdr *newopt,
896 int newoptlen)
897{
898 struct ipv6_txoptions *ret_val;
899 const mm_segment_t old_fs = get_fs();
900
901 set_fs(KERNEL_DS);
902 ret_val = ipv6_renew_options(sk, opt, newtype,
903 (struct ipv6_opt_hdr __user *)newopt,
904 newoptlen);
905 set_fs(old_fs);
906 return ret_val;
907}
908
YOSHIFUJI Hideakidf9890c2005-11-20 12:23:18 +0900909struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
910 struct ipv6_txoptions *opt)
911{
912 /*
913 * ignore the dest before srcrt unless srcrt is being included.
914 * --yoshfuji
915 */
916 if (opt && opt->dst0opt && !opt->srcrt) {
917 if (opt_space != opt) {
918 memcpy(opt_space, opt, sizeof(*opt_space));
919 opt = opt_space;
920 }
921 opt->opt_nflen -= ipv6_optlen(opt->dst0opt);
922 opt->dst0opt = NULL;
923 }
924
925 return opt;
926}
Chris Elstona495f832012-04-29 21:48:53 +0000927EXPORT_SYMBOL_GPL(ipv6_fixup_options);
YOSHIFUJI Hideakidf9890c2005-11-20 12:23:18 +0900928
Arnaud Ebalard20c59de2010-06-01 21:35:01 +0000929/**
930 * fl6_update_dst - update flowi destination address with info given
931 * by srcrt option, if any.
932 *
David S. Miller4c9483b2011-03-12 16:22:43 -0500933 * @fl6: flowi6 for which daddr is to be updated
Arnaud Ebalard20c59de2010-06-01 21:35:01 +0000934 * @opt: struct ipv6_txoptions in which to look for srcrt opt
David S. Miller4c9483b2011-03-12 16:22:43 -0500935 * @orig: copy of original daddr address if modified
Arnaud Ebalard20c59de2010-06-01 21:35:01 +0000936 *
937 * Returns NULL if no txoptions or no srcrt, otherwise returns orig
David S. Miller4c9483b2011-03-12 16:22:43 -0500938 * and initial value of fl6->daddr set in orig
Arnaud Ebalard20c59de2010-06-01 21:35:01 +0000939 */
David S. Miller4c9483b2011-03-12 16:22:43 -0500940struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
Arnaud Ebalard20c59de2010-06-01 21:35:01 +0000941 const struct ipv6_txoptions *opt,
942 struct in6_addr *orig)
943{
944 if (!opt || !opt->srcrt)
945 return NULL;
946
Alexey Dobriyan4e3fd7a2011-11-21 03:39:03 +0000947 *orig = fl6->daddr;
948 fl6->daddr = *((struct rt0_hdr *)opt->srcrt)->addr;
Arnaud Ebalard20c59de2010-06-01 21:35:01 +0000949 return orig;
950}
Arnaud Ebalard20c59de2010-06-01 21:35:01 +0000951EXPORT_SYMBOL_GPL(fl6_update_dst);