blob: 473f628f9f203d2e0c58466f32603ce50a330402 [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>
Amerigo Wang07a93622012-10-29 16:23:10 +000046#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -070047#include <net/xfrm.h>
48#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070049
50#include <asm/uaccess.h>
51
52/*
53 * Parsing tlv encoded headers.
54 *
Eric Dumazeta50feda2012-05-18 18:57:34 +000055 * Parsing function "func" returns true, if parsing succeed
56 * and false, if it failed.
Linus Torvalds1da177e2005-04-16 15:20:36 -070057 * It MUST NOT touch skb->h.
58 */
59
60struct tlvtype_proc {
61 int type;
Eric Dumazeta50feda2012-05-18 18:57:34 +000062 bool (*func)(struct sk_buff *skb, int offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -070063};
64
65/*********************
66 Generic functions
67 *********************/
68
69/* An unknown option is detected, decide what to do */
70
Eric Dumazeta50feda2012-05-18 18:57:34 +000071static bool ip6_tlvopt_unknown(struct sk_buff *skb, int optoff)
Linus Torvalds1da177e2005-04-16 15:20:36 -070072{
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -070073 switch ((skb_network_header(skb)[optoff] & 0xC0) >> 6) {
Linus Torvalds1da177e2005-04-16 15:20:36 -070074 case 0: /* ignore */
Eric Dumazeta50feda2012-05-18 18:57:34 +000075 return true;
Linus Torvalds1da177e2005-04-16 15:20:36 -070076
77 case 1: /* drop packet */
78 break;
79
80 case 3: /* Send ICMP if not a multicast address and drop packet */
81 /* Actually, it is redundant check. icmp_send
82 will recheck in any case.
83 */
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -070084 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr))
Linus Torvalds1da177e2005-04-16 15:20:36 -070085 break;
86 case 2: /* send ICMP PARM PROB regardless and drop packet */
87 icmpv6_param_prob(skb, ICMPV6_UNK_OPTION, optoff);
Eric Dumazeta50feda2012-05-18 18:57:34 +000088 return false;
Stephen Hemminger3ff50b72007-04-20 17:09:22 -070089 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070090
91 kfree_skb(skb);
Eric Dumazeta50feda2012-05-18 18:57:34 +000092 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -070093}
94
95/* Parse tlv encoded option header (hop-by-hop or destination) */
96
Eric Dumazeta50feda2012-05-18 18:57:34 +000097static bool ip6_parse_tlv(const struct tlvtype_proc *procs, struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -070098{
Eric Dumazeta50feda2012-05-18 18:57:34 +000099 const struct tlvtype_proc *curr;
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700100 const unsigned char *nh = skb_network_header(skb);
Arnaldo Carvalho de Melocfe1fc72007-03-16 17:26:39 -0300101 int off = skb_network_header_len(skb);
Arnaldo Carvalho de Melo9c702202007-04-25 18:04:18 -0700102 int len = (skb_transport_header(skb)[1] + 1) << 3;
Eldad Zack9b905fe2012-05-20 01:59:33 +0000103 int padlen = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104
Arnaldo Carvalho de Meloea2ae172007-04-25 17:55:53 -0700105 if (skb_transport_offset(skb) + len > skb_headlen(skb))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106 goto bad;
107
108 off += 2;
109 len -= 2;
110
111 while (len > 0) {
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700112 int optlen = nh[off + 1] + 2;
Eldad Zackc1412fc2012-04-12 17:36:17 -0400113 int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700115 switch (nh[off]) {
Eldad Zack1de5a712012-05-17 06:00:25 +0000116 case IPV6_TLV_PAD1:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117 optlen = 1;
Eldad Zack9b905fe2012-05-20 01:59:33 +0000118 padlen++;
119 if (padlen > 7)
120 goto bad;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121 break;
122
123 case IPV6_TLV_PADN:
Eldad Zackc1412fc2012-04-12 17:36:17 -0400124 /* RFC 2460 states that the purpose of PadN is
125 * to align the containing header to multiples
126 * of 8. 7 is therefore the highest valid value.
127 * See also RFC 4942, Section 2.1.9.5.
128 */
Eldad Zack9b905fe2012-05-20 01:59:33 +0000129 padlen += optlen;
130 if (padlen > 7)
Eldad Zackc1412fc2012-04-12 17:36:17 -0400131 goto bad;
132 /* RFC 4942 recommends receiving hosts to
133 * actively check PadN payload to contain
134 * only zeroes.
135 */
136 for (i = 2; i < optlen; i++) {
137 if (nh[off + i] != 0)
138 goto bad;
139 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 break;
141
142 default: /* Other TLV code so scan list */
143 if (optlen > len)
144 goto bad;
145 for (curr=procs; curr->type >= 0; curr++) {
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700146 if (curr->type == nh[off]) {
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900147 /* type specific length/alignment
148 checks will be performed in the
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149 func(). */
Eric Dumazeta50feda2012-05-18 18:57:34 +0000150 if (curr->func(skb, off) == false)
151 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152 break;
153 }
154 }
155 if (curr->type < 0) {
Herbert Xue5bbef22007-10-15 12:50:28 -0700156 if (ip6_tlvopt_unknown(skb, off) == 0)
Eric Dumazeta50feda2012-05-18 18:57:34 +0000157 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158 }
Eldad Zack9b905fe2012-05-20 01:59:33 +0000159 padlen = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 break;
161 }
162 off += optlen;
163 len -= optlen;
164 }
Eldad Zack9b905fe2012-05-20 01:59:33 +0000165 /* This case will not be caught by above check since its padding
166 * length is smaller than 7:
167 * 1 byte NH + 1 byte Length + 6 bytes Padding
168 */
169 if ((padlen == 6) && ((off - skb_network_header_len(skb)) == 8))
170 goto bad;
171
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 if (len == 0)
Eric Dumazeta50feda2012-05-18 18:57:34 +0000173 return true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174bad:
175 kfree_skb(skb);
Eric Dumazeta50feda2012-05-18 18:57:34 +0000176 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177}
178
179/*****************************
180 Destination options header.
181 *****************************/
182
Amerigo Wang07a93622012-10-29 16:23:10 +0000183#if IS_ENABLED(CONFIG_IPV6_MIP6)
Eric Dumazeta50feda2012-05-18 18:57:34 +0000184static bool ipv6_dest_hao(struct sk_buff *skb, int optoff)
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700185{
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700186 struct ipv6_destopt_hao *hao;
187 struct inet6_skb_parm *opt = IP6CB(skb);
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700188 struct ipv6hdr *ipv6h = ipv6_hdr(skb);
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700189 struct in6_addr tmp_addr;
190 int ret;
191
192 if (opt->dsthao) {
193 LIMIT_NETDEBUG(KERN_DEBUG "hao duplicated\n");
194 goto discard;
195 }
196 opt->dsthao = opt->dst1;
197 opt->dst1 = 0;
198
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700199 hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff);
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700200
201 if (hao->length != 16) {
202 LIMIT_NETDEBUG(
203 KERN_DEBUG "hao invalid option length = %d\n", hao->length);
204 goto discard;
205 }
206
207 if (!(ipv6_addr_type(&hao->addr) & IPV6_ADDR_UNICAST)) {
208 LIMIT_NETDEBUG(
Harvey Harrison5b095d9892008-10-29 12:52:50 -0700209 KERN_DEBUG "hao is not an unicast addr: %pI6\n", &hao->addr);
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700210 goto discard;
211 }
212
213 ret = xfrm6_input_addr(skb, (xfrm_address_t *)&ipv6h->daddr,
214 (xfrm_address_t *)&hao->addr, IPPROTO_DSTOPTS);
215 if (unlikely(ret < 0))
216 goto discard;
217
218 if (skb_cloned(skb)) {
Herbert Xu65c88462007-10-15 01:29:10 -0700219 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700220 goto discard;
221
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700222 /* update all variable using below by copied skbuff */
Herbert Xu65c88462007-10-15 01:29:10 -0700223 hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) +
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700224 optoff);
Herbert Xu65c88462007-10-15 01:29:10 -0700225 ipv6h = ipv6_hdr(skb);
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700226 }
227
228 if (skb->ip_summed == CHECKSUM_COMPLETE)
229 skb->ip_summed = CHECKSUM_NONE;
230
Alexey Dobriyan4e3fd7a2011-11-21 03:39:03 +0000231 tmp_addr = ipv6h->saddr;
232 ipv6h->saddr = hao->addr;
233 hao->addr = tmp_addr;
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700234
Eric Dumazetb7aa0bf2007-04-19 16:16:32 -0700235 if (skb->tstamp.tv64 == 0)
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700236 __net_timestamp(skb);
237
Eric Dumazeta50feda2012-05-18 18:57:34 +0000238 return true;
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700239
240 discard:
241 kfree_skb(skb);
Eric Dumazeta50feda2012-05-18 18:57:34 +0000242 return false;
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700243}
244#endif
245
Eric Dumazeta50feda2012-05-18 18:57:34 +0000246static const struct tlvtype_proc tlvprocdestopt_lst[] = {
Amerigo Wang07a93622012-10-29 16:23:10 +0000247#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700248 {
249 .type = IPV6_TLV_HAO,
250 .func = ipv6_dest_hao,
251 },
252#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253 {-1, NULL}
254};
255
Herbert Xue5bbef22007-10-15 12:50:28 -0700256static int ipv6_destopt_rcv(struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700257{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 struct inet6_skb_parm *opt = IP6CB(skb);
Amerigo Wang07a93622012-10-29 16:23:10 +0000259#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700260 __u16 dstbuf;
261#endif
Eric Dumazet897dc802011-07-28 04:00:35 +0000262 struct dst_entry *dst = skb_dst(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263
Arnaldo Carvalho de Meloea2ae172007-04-25 17:55:53 -0700264 if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) ||
265 !pskb_may_pull(skb, (skb_transport_offset(skb) +
Arnaldo Carvalho de Melo9c702202007-04-25 18:04:18 -0700266 ((skb_transport_header(skb)[1] + 1) << 3)))) {
Eric Dumazet897dc802011-07-28 04:00:35 +0000267 IP6_INC_STATS_BH(dev_net(dst->dev), ip6_dst_idev(dst),
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900268 IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 kfree_skb(skb);
270 return -1;
271 }
272
Arnaldo Carvalho de Melocfe1fc72007-03-16 17:26:39 -0300273 opt->lastopt = opt->dst1 = skb_network_header_len(skb);
Amerigo Wang07a93622012-10-29 16:23:10 +0000274#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700275 dstbuf = opt->dst1;
276#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277
Herbert Xue5bbef22007-10-15 12:50:28 -0700278 if (ip6_parse_tlv(tlvprocdestopt_lst, skb)) {
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700279 skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3;
Masahide NAKAMURAdc435e62006-08-31 15:18:49 -0700280 opt = IP6CB(skb);
Amerigo Wang07a93622012-10-29 16:23:10 +0000281#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700282 opt->nhoff = dstbuf;
283#else
Patrick McHardy951dbc82006-01-06 23:02:34 -0800284 opt->nhoff = opt->dst1;
Masahide NAKAMURAa831f5b2006-08-23 19:24:48 -0700285#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700286 return 1;
287 }
288
Denis V. Lunev483a47d2008-10-08 11:09:27 -0700289 IP6_INC_STATS_BH(dev_net(dst->dev),
290 ip6_dst_idev(dst), IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 return -1;
292}
293
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294/********************************
295 Routing header.
296 ********************************/
297
Eric Dumazetf6bc7d92010-06-14 04:39:27 +0000298/* called with rcu_read_lock() */
Herbert Xue5bbef22007-10-15 12:50:28 -0700299static int ipv6_rthdr_rcv(struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301 struct inet6_skb_parm *opt = IP6CB(skb);
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700302 struct in6_addr *addr = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700303 struct in6_addr daddr;
YOSHIFUJI Hideaki0bcbc922007-04-24 14:58:30 -0700304 struct inet6_dev *idev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305 int n, i;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306 struct ipv6_rt_hdr *hdr;
307 struct rt0_hdr *rthdr;
Denis V. Lunev483a47d2008-10-08 11:09:27 -0700308 struct net *net = dev_net(skb->dev);
309 int accept_source_route = net->ipv6.devconf_all->accept_source_route;
YOSHIFUJI Hideaki0bcbc922007-04-24 14:58:30 -0700310
Eric Dumazetf6bc7d92010-06-14 04:39:27 +0000311 idev = __in6_dev_get(skb->dev);
312 if (idev && accept_source_route > idev->cnf.accept_source_route)
313 accept_source_route = idev->cnf.accept_source_route;
YOSHIFUJI Hideaki0bcbc922007-04-24 14:58:30 -0700314
Arnaldo Carvalho de Meloea2ae172007-04-25 17:55:53 -0700315 if (!pskb_may_pull(skb, skb_transport_offset(skb) + 8) ||
316 !pskb_may_pull(skb, (skb_transport_offset(skb) +
Arnaldo Carvalho de Melo9c702202007-04-25 18:04:18 -0700317 ((skb_transport_header(skb)[1] + 1) << 3)))) {
Eric Dumazetadf30902009-06-02 05:19:30 +0000318 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900319 IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320 kfree_skb(skb);
321 return -1;
322 }
323
Arnaldo Carvalho de Melo9c702202007-04-25 18:04:18 -0700324 hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700326 if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr) ||
Linus Torvalds1da177e2005-04-16 15:20:36 -0700327 skb->pkt_type != PACKET_HOST) {
Eric Dumazetadf30902009-06-02 05:19:30 +0000328 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900329 IPSTATS_MIB_INADDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330 kfree_skb(skb);
331 return -1;
332 }
333
334looped_back:
335 if (hdr->segments_left == 0) {
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700336 switch (hdr->type) {
Amerigo Wang07a93622012-10-29 16:23:10 +0000337#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700338 case IPV6_SRCRT_TYPE_2:
339 /* Silently discard type 2 header unless it was
340 * processed by own
341 */
342 if (!addr) {
Eric Dumazetadf30902009-06-02 05:19:30 +0000343 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900344 IPSTATS_MIB_INADDRERRORS);
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700345 kfree_skb(skb);
346 return -1;
347 }
348 break;
349#endif
350 default:
351 break;
352 }
353
Arnaldo Carvalho de Melocfe1fc72007-03-16 17:26:39 -0300354 opt->lastopt = opt->srcrt = skb_network_header_len(skb);
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700355 skb->transport_header += (hdr->hdrlen + 1) << 3;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356 opt->dst0 = opt->dst1;
357 opt->dst1 = 0;
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700358 opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 return 1;
360 }
361
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700362 switch (hdr->type) {
Amerigo Wang07a93622012-10-29 16:23:10 +0000363#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700364 case IPV6_SRCRT_TYPE_2:
YOSHIFUJI Hideakic382bb92007-07-10 22:47:58 -0700365 if (accept_source_route < 0)
366 goto unknown_rh;
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700367 /* Silently discard invalid RTH type 2 */
368 if (hdr->hdrlen != 2 || hdr->segments_left != 1) {
Eric Dumazetadf30902009-06-02 05:19:30 +0000369 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900370 IPSTATS_MIB_INHDRERRORS);
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700371 kfree_skb(skb);
372 return -1;
373 }
374 break;
375#endif
YOSHIFUJI Hideakic382bb92007-07-10 22:47:58 -0700376 default:
377 goto unknown_rh;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379
380 /*
381 * This is the routing header forwarding algorithm from
382 * RFC 2460, page 16.
383 */
384
385 n = hdr->hdrlen >> 1;
386
387 if (hdr->segments_left > n) {
Eric Dumazetadf30902009-06-02 05:19:30 +0000388 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900389 IPSTATS_MIB_INHDRERRORS);
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700390 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
391 ((&hdr->segments_left) -
392 skb_network_header(skb)));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393 return -1;
394 }
395
396 /* We are about to mangle packet header. Be careful!
397 Do not damage packets queued somewhere.
398 */
399 if (skb_cloned(skb)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 /* the copy is a forwarded packet */
Herbert Xu65c88462007-10-15 01:29:10 -0700401 if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
Eric Dumazetadf30902009-06-02 05:19:30 +0000402 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900403 IPSTATS_MIB_OUTDISCARDS);
404 kfree_skb(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405 return -1;
406 }
Herbert Xu65c88462007-10-15 01:29:10 -0700407 hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700408 }
409
Patrick McHardy84fa7932006-08-29 16:44:56 -0700410 if (skb->ip_summed == CHECKSUM_COMPLETE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411 skb->ip_summed = CHECKSUM_NONE;
412
413 i = n - --hdr->segments_left;
414
415 rthdr = (struct rt0_hdr *) hdr;
416 addr = rthdr->addr;
417 addr += i - 1;
418
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700419 switch (hdr->type) {
Amerigo Wang07a93622012-10-29 16:23:10 +0000420#if IS_ENABLED(CONFIG_IPV6_MIP6)
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700421 case IPV6_SRCRT_TYPE_2:
422 if (xfrm6_input_addr(skb, (xfrm_address_t *)addr,
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700423 (xfrm_address_t *)&ipv6_hdr(skb)->saddr,
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700424 IPPROTO_ROUTING) < 0) {
Eric Dumazetadf30902009-06-02 05:19:30 +0000425 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900426 IPSTATS_MIB_INADDRERRORS);
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700427 kfree_skb(skb);
428 return -1;
429 }
Eric Dumazetadf30902009-06-02 05:19:30 +0000430 if (!ipv6_chk_home_addr(dev_net(skb_dst(skb)->dev), addr)) {
431 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900432 IPSTATS_MIB_INADDRERRORS);
Masahide NAKAMURA65d4ed92006-08-23 19:16:22 -0700433 kfree_skb(skb);
434 return -1;
435 }
436 break;
437#endif
438 default:
439 break;
440 }
441
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442 if (ipv6_addr_is_multicast(addr)) {
Eric Dumazetadf30902009-06-02 05:19:30 +0000443 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900444 IPSTATS_MIB_INADDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445 kfree_skb(skb);
446 return -1;
447 }
448
Alexey Dobriyan4e3fd7a2011-11-21 03:39:03 +0000449 daddr = *addr;
450 *addr = ipv6_hdr(skb)->daddr;
451 ipv6_hdr(skb)->daddr = daddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452
Eric Dumazetadf30902009-06-02 05:19:30 +0000453 skb_dst_drop(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454 ip6_route_input(skb);
Eric Dumazetadf30902009-06-02 05:19:30 +0000455 if (skb_dst(skb)->error) {
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700456 skb_push(skb, skb->data - skb_network_header(skb));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457 dst_input(skb);
458 return -1;
459 }
460
Eric Dumazetadf30902009-06-02 05:19:30 +0000461 if (skb_dst(skb)->dev->flags&IFF_LOOPBACK) {
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700462 if (ipv6_hdr(skb)->hop_limit <= 1) {
Eric Dumazetadf30902009-06-02 05:19:30 +0000463 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900464 IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465 icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT,
Alexey Dobriyan3ffe5332010-02-18 08:25:24 +0000466 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467 kfree_skb(skb);
468 return -1;
469 }
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700470 ipv6_hdr(skb)->hop_limit--;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700471 goto looped_back;
472 }
473
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700474 skb_push(skb, skb->data - skb_network_header(skb));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 dst_input(skb);
476 return -1;
YOSHIFUJI Hideakic382bb92007-07-10 22:47:58 -0700477
478unknown_rh:
Eric Dumazetadf30902009-06-02 05:19:30 +0000479 IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS);
YOSHIFUJI Hideakic382bb92007-07-10 22:47:58 -0700480 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
481 (&hdr->type) - skb_network_header(skb));
482 return -1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483}
484
Alexey Dobriyan41135cc2009-09-14 12:22:28 +0000485static const struct inet6_protocol rthdr_protocol = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700486 .handler = ipv6_rthdr_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 destopt_protocol = {
Daniel Lezcano248b2382007-12-11 02:23:54 -0800491 .handler = ipv6_destopt_rcv,
Vlad Yasevich2207afc2012-11-15 08:49:19 +0000492 .flags = INET6_PROTO_NOPOLICY,
Vlad Yasevich8ca896c2012-11-15 08:49:13 +0000493};
494
Alexey Dobriyan41135cc2009-09-14 12:22:28 +0000495static const struct inet6_protocol nodata_protocol = {
Daniel Lezcano248b2382007-12-11 02:23:54 -0800496 .handler = dst_discard,
497 .flags = INET6_PROTO_NOPOLICY,
498};
499
500int __init ipv6_exthdrs_init(void)
501{
502 int ret;
503
Vlad Yasevich33362882012-11-15 08:49:15 +0000504 ret = inet6_add_protocol(&rthdr_protocol, IPPROTO_ROUTING);
505 if (ret)
Vlad Yasevichc6b641a2012-11-15 08:49:22 +0000506 goto out;
Vlad Yasevich33362882012-11-15 08:49:15 +0000507
Daniel Lezcano248b2382007-12-11 02:23:54 -0800508 ret = inet6_add_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
509 if (ret)
510 goto out_rthdr;
511
512 ret = inet6_add_protocol(&nodata_protocol, IPPROTO_NONE);
513 if (ret)
514 goto out_destopt;
515
516out:
517 return ret;
Daniel Lezcano248b2382007-12-11 02:23:54 -0800518out_destopt:
519 inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
Vlad Yasevich33362882012-11-15 08:49:15 +0000520out_rthdr:
521 inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING);
Daniel Lezcano248b2382007-12-11 02:23:54 -0800522 goto out;
523};
524
525void ipv6_exthdrs_exit(void)
526{
527 inet6_del_protocol(&nodata_protocol, IPPROTO_NONE);
528 inet6_del_protocol(&destopt_protocol, IPPROTO_DSTOPTS);
529 inet6_del_protocol(&rthdr_protocol, IPPROTO_ROUTING);
530}
531
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532/**********************************
533 Hop-by-hop options.
534 **********************************/
535
YOSHIFUJI Hideakie76b2b22007-05-09 14:01:59 -0700536/*
Eric Dumazetadf30902009-06-02 05:19:30 +0000537 * Note: we cannot rely on skb_dst(skb) before we assign it in ip6_route_input().
YOSHIFUJI Hideakie76b2b22007-05-09 14:01:59 -0700538 */
539static inline struct inet6_dev *ipv6_skb_idev(struct sk_buff *skb)
540{
Eric Dumazetadf30902009-06-02 05:19:30 +0000541 return skb_dst(skb) ? ip6_dst_idev(skb_dst(skb)) : __in6_dev_get(skb->dev);
YOSHIFUJI Hideakie76b2b22007-05-09 14:01:59 -0700542}
543
David S. Miller2570a4f2010-01-13 17:27:37 -0800544static inline struct net *ipv6_skb_net(struct sk_buff *skb)
545{
546 return skb_dst(skb) ? dev_net(skb_dst(skb)->dev) : dev_net(skb->dev);
547}
548
Linus Torvalds1da177e2005-04-16 15:20:36 -0700549/* Router Alert as of RFC 2711 */
550
Eric Dumazeta50feda2012-05-18 18:57:34 +0000551static bool ipv6_hop_ra(struct sk_buff *skb, int optoff)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552{
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700553 const unsigned char *nh = skb_network_header(skb);
Masahide NAKAMURAa80ff032006-08-23 19:19:50 -0700554
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700555 if (nh[optoff + 1] == 2) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 IP6CB(skb)->ra = optoff;
Eric Dumazeta50feda2012-05-18 18:57:34 +0000557 return true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700558 }
Patrick McHardy64ce2072005-08-09 20:50:53 -0700559 LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_ra: wrong RA length %d\n",
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700560 nh[optoff + 1]);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700561 kfree_skb(skb);
Eric Dumazeta50feda2012-05-18 18:57:34 +0000562 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700563}
564
565/* Jumbo payload */
566
Eric Dumazeta50feda2012-05-18 18:57:34 +0000567static bool ipv6_hop_jumbo(struct sk_buff *skb, int optoff)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568{
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700569 const unsigned char *nh = skb_network_header(skb);
David S. Miller2570a4f2010-01-13 17:27:37 -0800570 struct net *net = ipv6_skb_net(skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571 u32 pkt_len;
572
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700573 if (nh[optoff + 1] != 4 || (optoff & 3) != 2) {
Patrick McHardy64ce2072005-08-09 20:50:53 -0700574 LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n",
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700575 nh[optoff+1]);
Denis V. Lunev483a47d2008-10-08 11:09:27 -0700576 IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
YOSHIFUJI Hideakia11d2062006-11-04 20:11:37 +0900577 IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700578 goto drop;
579 }
580
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700581 pkt_len = ntohl(*(__be32 *)(nh + optoff + 2));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700582 if (pkt_len <= IPV6_MAXPLEN) {
Denis V. Lunev483a47d2008-10-08 11:09:27 -0700583 IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
584 IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2);
Eric Dumazeta50feda2012-05-18 18:57:34 +0000586 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587 }
Arnaldo Carvalho de Melo0660e032007-04-25 17:54:47 -0700588 if (ipv6_hdr(skb)->payload_len) {
Denis V. Lunev483a47d2008-10-08 11:09:27 -0700589 IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
590 IPSTATS_MIB_INHDRERRORS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591 icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff);
Eric Dumazeta50feda2012-05-18 18:57:34 +0000592 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 }
594
595 if (pkt_len > skb->len - sizeof(struct ipv6hdr)) {
Denis V. Lunev483a47d2008-10-08 11:09:27 -0700596 IP6_INC_STATS_BH(net, ipv6_skb_idev(skb),
597 IPSTATS_MIB_INTRUNCATEDPKTS);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700598 goto drop;
599 }
Stephen Hemminger42ca89c2005-09-08 12:57:43 -0700600
601 if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr)))
602 goto drop;
603
Eric Dumazeta50feda2012-05-18 18:57:34 +0000604 return true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605
606drop:
607 kfree_skb(skb);
Eric Dumazeta50feda2012-05-18 18:57:34 +0000608 return false;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609}
610
Eric Dumazeta50feda2012-05-18 18:57:34 +0000611static const struct tlvtype_proc tlvprochopopt_lst[] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700612 {
613 .type = IPV6_TLV_ROUTERALERT,
614 .func = ipv6_hop_ra,
615 },
616 {
617 .type = IPV6_TLV_JUMBO,
618 .func = ipv6_hop_jumbo,
619 },
620 { -1, }
621};
622
Herbert Xue5bbef22007-10-15 12:50:28 -0700623int ipv6_parse_hopopts(struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624{
Patrick McHardy951dbc82006-01-06 23:02:34 -0800625 struct inet6_skb_parm *opt = IP6CB(skb);
626
YOSHIFUJI Hideakiec670092006-04-18 14:46:26 -0700627 /*
Arnaldo Carvalho de Melod56f90a2007-04-10 20:50:43 -0700628 * skb_network_header(skb) is equal to skb->data, and
Arnaldo Carvalho de Melocfe1fc72007-03-16 17:26:39 -0300629 * skb_network_header_len(skb) is always equal to
YOSHIFUJI Hideakiec670092006-04-18 14:46:26 -0700630 * sizeof(struct ipv6hdr) by definition of
631 * hop-by-hop options.
632 */
633 if (!pskb_may_pull(skb, sizeof(struct ipv6hdr) + 8) ||
Arnaldo Carvalho de Melo9c702202007-04-25 18:04:18 -0700634 !pskb_may_pull(skb, (sizeof(struct ipv6hdr) +
635 ((skb_transport_header(skb)[1] + 1) << 3)))) {
YOSHIFUJI Hideakiec670092006-04-18 14:46:26 -0700636 kfree_skb(skb);
637 return -1;
638 }
639
Patrick McHardy951dbc82006-01-06 23:02:34 -0800640 opt->hop = sizeof(struct ipv6hdr);
Herbert Xue5bbef22007-10-15 12:50:28 -0700641 if (ip6_parse_tlv(tlvprochopopt_lst, skb)) {
Arnaldo Carvalho de Melob0e380b2007-04-10 21:21:55 -0700642 skb->transport_header += (skb_transport_header(skb)[1] + 1) << 3;
Masahide NAKAMURAdc435e62006-08-31 15:18:49 -0700643 opt = IP6CB(skb);
Patrick McHardy951dbc82006-01-06 23:02:34 -0800644 opt->nhoff = sizeof(struct ipv6hdr);
YOSHIFUJI Hideakib8097392006-04-18 14:48:45 -0700645 return 1;
Patrick McHardy951dbc82006-01-06 23:02:34 -0800646 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700647 return -1;
648}
649
650/*
651 * Creating outbound headers.
652 *
653 * "build" functions work when skb is filled from head to tail (datagram)
654 * "push" functions work when headers are added from tail to head (tcp)
655 *
656 * In both cases we assume, that caller reserved enough room
657 * for headers.
658 */
659
660static void ipv6_push_rthdr(struct sk_buff *skb, u8 *proto,
661 struct ipv6_rt_hdr *opt,
662 struct in6_addr **addr_p)
663{
664 struct rt0_hdr *phdr, *ihdr;
665 int hops;
666
667 ihdr = (struct rt0_hdr *) opt;
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900668
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669 phdr = (struct rt0_hdr *) skb_push(skb, (ihdr->rt_hdr.hdrlen + 1) << 3);
670 memcpy(phdr, ihdr, sizeof(struct rt0_hdr));
671
672 hops = ihdr->rt_hdr.hdrlen >> 1;
673
674 if (hops > 1)
675 memcpy(phdr->addr, ihdr->addr + 1,
676 (hops - 1) * sizeof(struct in6_addr));
677
Alexey Dobriyan4e3fd7a2011-11-21 03:39:03 +0000678 phdr->addr[hops - 1] = **addr_p;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700679 *addr_p = ihdr->addr;
680
681 phdr->rt_hdr.nexthdr = *proto;
682 *proto = NEXTHDR_ROUTING;
683}
684
685static void ipv6_push_exthdr(struct sk_buff *skb, u8 *proto, u8 type, struct ipv6_opt_hdr *opt)
686{
687 struct ipv6_opt_hdr *h = (struct ipv6_opt_hdr *)skb_push(skb, ipv6_optlen(opt));
688
689 memcpy(h, opt, ipv6_optlen(opt));
690 h->nexthdr = *proto;
691 *proto = type;
692}
693
694void ipv6_push_nfrag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt,
695 u8 *proto,
696 struct in6_addr **daddr)
697{
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900698 if (opt->srcrt) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699 ipv6_push_rthdr(skb, proto, opt->srcrt, daddr);
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900700 /*
701 * IPV6_RTHDRDSTOPTS is ignored
702 * unless IPV6_RTHDR is set (RFC3542).
703 */
704 if (opt->dst0opt)
705 ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst0opt);
706 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700707 if (opt->hopopt)
708 ipv6_push_exthdr(skb, proto, NEXTHDR_HOP, opt->hopopt);
709}
YOSHIFUJI Hideaki71590392007-02-22 22:05:40 +0900710EXPORT_SYMBOL(ipv6_push_nfrag_opts);
711
Linus Torvalds1da177e2005-04-16 15:20:36 -0700712void ipv6_push_frag_opts(struct sk_buff *skb, struct ipv6_txoptions *opt, u8 *proto)
713{
714 if (opt->dst1opt)
715 ipv6_push_exthdr(skb, proto, NEXTHDR_DEST, opt->dst1opt);
716}
717
718struct ipv6_txoptions *
719ipv6_dup_options(struct sock *sk, struct ipv6_txoptions *opt)
720{
721 struct ipv6_txoptions *opt2;
722
723 opt2 = sock_kmalloc(sk, opt->tot_len, GFP_ATOMIC);
724 if (opt2) {
Eldad Zackac3c8172012-04-01 07:49:04 +0000725 long dif = (char *)opt2 - (char *)opt;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726 memcpy(opt2, opt, opt->tot_len);
727 if (opt2->hopopt)
Eldad Zackac3c8172012-04-01 07:49:04 +0000728 *((char **)&opt2->hopopt) += dif;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729 if (opt2->dst0opt)
Eldad Zackac3c8172012-04-01 07:49:04 +0000730 *((char **)&opt2->dst0opt) += dif;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731 if (opt2->dst1opt)
Eldad Zackac3c8172012-04-01 07:49:04 +0000732 *((char **)&opt2->dst1opt) += dif;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733 if (opt2->srcrt)
Eldad Zackac3c8172012-04-01 07:49:04 +0000734 *((char **)&opt2->srcrt) += dif;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700735 }
736 return opt2;
737}
Arnaldo Carvalho de Melo3cf3dc62005-12-13 23:23:20 -0800738EXPORT_SYMBOL_GPL(ipv6_dup_options);
739
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900740static int ipv6_renew_option(void *ohdr,
741 struct ipv6_opt_hdr __user *newopt, int newoptlen,
742 int inherit,
743 struct ipv6_opt_hdr **hdr,
744 char **p)
745{
746 if (inherit) {
747 if (ohdr) {
748 memcpy(*p, ohdr, ipv6_optlen((struct ipv6_opt_hdr *)ohdr));
749 *hdr = (struct ipv6_opt_hdr *)*p;
Joe Perchese3192692012-06-03 17:41:40 +0000750 *p += CMSG_ALIGN(ipv6_optlen(*hdr));
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900751 }
752 } else {
753 if (newopt) {
754 if (copy_from_user(*p, newopt, newoptlen))
755 return -EFAULT;
756 *hdr = (struct ipv6_opt_hdr *)*p;
Joe Perchese3192692012-06-03 17:41:40 +0000757 if (ipv6_optlen(*hdr) > newoptlen)
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900758 return -EINVAL;
759 *p += CMSG_ALIGN(newoptlen);
760 }
761 }
762 return 0;
763}
764
765struct ipv6_txoptions *
766ipv6_renew_options(struct sock *sk, struct ipv6_txoptions *opt,
767 int newtype,
768 struct ipv6_opt_hdr __user *newopt, int newoptlen)
769{
770 int tot_len = 0;
771 char *p;
772 struct ipv6_txoptions *opt2;
773 int err;
774
YOSHIFUJI Hideaki99c7bc02006-08-31 14:52:17 -0700775 if (opt) {
776 if (newtype != IPV6_HOPOPTS && opt->hopopt)
777 tot_len += CMSG_ALIGN(ipv6_optlen(opt->hopopt));
778 if (newtype != IPV6_RTHDRDSTOPTS && opt->dst0opt)
779 tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst0opt));
780 if (newtype != IPV6_RTHDR && opt->srcrt)
781 tot_len += CMSG_ALIGN(ipv6_optlen(opt->srcrt));
782 if (newtype != IPV6_DSTOPTS && opt->dst1opt)
783 tot_len += CMSG_ALIGN(ipv6_optlen(opt->dst1opt));
784 }
785
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900786 if (newopt && newoptlen)
787 tot_len += CMSG_ALIGN(newoptlen);
788
789 if (!tot_len)
790 return NULL;
791
YOSHIFUJI Hideaki8b8aa4b2005-11-20 12:18:17 +0900792 tot_len += sizeof(*opt2);
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900793 opt2 = sock_kmalloc(sk, tot_len, GFP_ATOMIC);
794 if (!opt2)
795 return ERR_PTR(-ENOBUFS);
796
797 memset(opt2, 0, tot_len);
798
799 opt2->tot_len = tot_len;
800 p = (char *)(opt2 + 1);
801
YOSHIFUJI Hideaki99c7bc02006-08-31 14:52:17 -0700802 err = ipv6_renew_option(opt ? opt->hopopt : NULL, newopt, newoptlen,
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900803 newtype != IPV6_HOPOPTS,
804 &opt2->hopopt, &p);
805 if (err)
806 goto out;
807
YOSHIFUJI Hideaki99c7bc02006-08-31 14:52:17 -0700808 err = ipv6_renew_option(opt ? opt->dst0opt : NULL, newopt, newoptlen,
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900809 newtype != IPV6_RTHDRDSTOPTS,
810 &opt2->dst0opt, &p);
811 if (err)
812 goto out;
813
YOSHIFUJI Hideaki99c7bc02006-08-31 14:52:17 -0700814 err = ipv6_renew_option(opt ? opt->srcrt : NULL, newopt, newoptlen,
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900815 newtype != IPV6_RTHDR,
YOSHIFUJI Hideaki99c7bc02006-08-31 14:52:17 -0700816 (struct ipv6_opt_hdr **)&opt2->srcrt, &p);
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900817 if (err)
818 goto out;
819
YOSHIFUJI Hideaki99c7bc02006-08-31 14:52:17 -0700820 err = ipv6_renew_option(opt ? opt->dst1opt : NULL, newopt, newoptlen,
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900821 newtype != IPV6_DSTOPTS,
822 &opt2->dst1opt, &p);
823 if (err)
824 goto out;
825
826 opt2->opt_nflen = (opt2->hopopt ? ipv6_optlen(opt2->hopopt) : 0) +
827 (opt2->dst0opt ? ipv6_optlen(opt2->dst0opt) : 0) +
828 (opt2->srcrt ? ipv6_optlen(opt2->srcrt) : 0);
829 opt2->opt_flen = (opt2->dst1opt ? ipv6_optlen(opt2->dst1opt) : 0);
830
831 return opt2;
832out:
YOSHIFUJI Hideaki8b8aa4b2005-11-20 12:18:17 +0900833 sock_kfree_s(sk, opt2, opt2->tot_len);
YOSHIFUJI Hideaki333fad52005-09-08 09:59:17 +0900834 return ERR_PTR(err);
835}
836
YOSHIFUJI Hideakidf9890c2005-11-20 12:23:18 +0900837struct ipv6_txoptions *ipv6_fixup_options(struct ipv6_txoptions *opt_space,
838 struct ipv6_txoptions *opt)
839{
840 /*
841 * ignore the dest before srcrt unless srcrt is being included.
842 * --yoshfuji
843 */
844 if (opt && opt->dst0opt && !opt->srcrt) {
845 if (opt_space != opt) {
846 memcpy(opt_space, opt, sizeof(*opt_space));
847 opt = opt_space;
848 }
849 opt->opt_nflen -= ipv6_optlen(opt->dst0opt);
850 opt->dst0opt = NULL;
851 }
852
853 return opt;
854}
Chris Elstona495f832012-04-29 21:48:53 +0000855EXPORT_SYMBOL_GPL(ipv6_fixup_options);
YOSHIFUJI Hideakidf9890c2005-11-20 12:23:18 +0900856
Arnaud Ebalard20c59de2010-06-01 21:35:01 +0000857/**
858 * fl6_update_dst - update flowi destination address with info given
859 * by srcrt option, if any.
860 *
David S. Miller4c9483b2011-03-12 16:22:43 -0500861 * @fl6: flowi6 for which daddr is to be updated
Arnaud Ebalard20c59de2010-06-01 21:35:01 +0000862 * @opt: struct ipv6_txoptions in which to look for srcrt opt
David S. Miller4c9483b2011-03-12 16:22:43 -0500863 * @orig: copy of original daddr address if modified
Arnaud Ebalard20c59de2010-06-01 21:35:01 +0000864 *
865 * Returns NULL if no txoptions or no srcrt, otherwise returns orig
David S. Miller4c9483b2011-03-12 16:22:43 -0500866 * and initial value of fl6->daddr set in orig
Arnaud Ebalard20c59de2010-06-01 21:35:01 +0000867 */
David S. Miller4c9483b2011-03-12 16:22:43 -0500868struct in6_addr *fl6_update_dst(struct flowi6 *fl6,
Arnaud Ebalard20c59de2010-06-01 21:35:01 +0000869 const struct ipv6_txoptions *opt,
870 struct in6_addr *orig)
871{
872 if (!opt || !opt->srcrt)
873 return NULL;
874
Alexey Dobriyan4e3fd7a2011-11-21 03:39:03 +0000875 *orig = fl6->daddr;
876 fl6->daddr = *((struct rt0_hdr *)opt->srcrt)->addr;
Arnaud Ebalard20c59de2010-06-01 21:35:01 +0000877 return orig;
878}
Arnaud Ebalard20c59de2010-06-01 21:35:01 +0000879EXPORT_SYMBOL_GPL(fl6_update_dst);