blob: 5636a912074acb8ecf445d9d6df753ff8e3eba95 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173
3 *
4 * Copyright (C)2003 USAGI/WIDE Project
5 *
6 * Author Mitsuru KANDA <mk@linux-ipv6.org>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +090012 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +090017 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070018 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21 */
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +090022/*
Linus Torvalds1da177e2005-04-16 15:20:36 -070023 * [Memo]
24 *
25 * Outbound:
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +090026 * The compression of IP datagram MUST be done before AH/ESP processing,
27 * fragmentation, and the addition of Hop-by-Hop/Routing header.
Linus Torvalds1da177e2005-04-16 15:20:36 -070028 *
29 * Inbound:
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +090030 * The decompression of IP datagram MUST be done after the reassembly,
Linus Torvalds1da177e2005-04-16 15:20:36 -070031 * AH/ESP processing.
32 */
Joe Perchesf3213832012-05-15 14:11:53 +000033
34#define pr_fmt(fmt) "IPv6: " fmt
35
Linus Torvalds1da177e2005-04-16 15:20:36 -070036#include <linux/module.h>
37#include <net/ip.h>
38#include <net/xfrm.h>
39#include <net/ipcomp.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070040#include <linux/crypto.h>
Herbert Xu4999f362007-11-07 02:21:47 -080041#include <linux/err.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070042#include <linux/pfkeyv2.h>
43#include <linux/random.h>
44#include <linux/percpu.h>
45#include <linux/smp.h>
46#include <linux/list.h>
47#include <linux/vmalloc.h>
48#include <linux/rtnetlink.h>
David S. Miller81aded22012-06-15 14:54:11 -070049#include <net/ip6_route.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070050#include <net/icmp.h>
51#include <net/ipv6.h>
Arnaldo Carvalho de Melo14c85022005-12-27 02:43:12 -020052#include <net/protocol.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070053#include <linux/ipv6.h>
54#include <linux/icmpv6.h>
Arjan van de Ven4a3e2f72006-03-20 22:33:17 -080055#include <linux/mutex.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070056
Linus Torvalds1da177e2005-04-16 15:20:36 -070057static void ipcomp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
Brian Haleyd5fdd6b2009-06-23 04:31:07 -070058 u8 type, u8 code, int offset, __be32 info)
Linus Torvalds1da177e2005-04-16 15:20:36 -070059{
Alexey Dobriyand74340d2010-01-25 10:39:09 +000060 struct net *net = dev_net(skb->dev);
Al Viroa94cfd12006-09-27 18:47:24 -070061 __be32 spi;
Eric Dumazetb71d1d42011-04-22 04:53:02 +000062 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
Herbert Xu87bdc482007-10-10 15:45:25 -070063 struct ip_comp_hdr *ipcomph =
64 (struct ip_comp_hdr *)(skb->data + offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -070065 struct xfrm_state *x;
66
David S. Millerec18d9a2012-07-12 00:25:15 -070067 if (type != ICMPV6_DEST_UNREACH &&
68 type != ICMPV6_PKT_TOOBIG &&
69 type != NDISC_REDIRECT)
Linus Torvalds1da177e2005-04-16 15:20:36 -070070 return;
71
Alexey Dobriyan4195f812006-05-22 16:53:22 -070072 spi = htonl(ntohs(ipcomph->cpi));
Eric Dumazetb71d1d42011-04-22 04:53:02 +000073 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
74 spi, IPPROTO_COMP, AF_INET6);
Linus Torvalds1da177e2005-04-16 15:20:36 -070075 if (!x)
76 return;
77
David S. Millerec18d9a2012-07-12 00:25:15 -070078 if (type == NDISC_REDIRECT)
Duan Jiongb55b76b2013-09-04 19:44:21 +080079 ip6_redirect(skb, net, skb->dev->ifindex, 0);
David S. Millerec18d9a2012-07-12 00:25:15 -070080 else
81 ip6_update_pmtu(skb, net, info, 0, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -070082 xfrm_state_put(x);
83}
84
85static struct xfrm_state *ipcomp6_tunnel_create(struct xfrm_state *x)
86{
Alexey Dobriyand74340d2010-01-25 10:39:09 +000087 struct net *net = xs_net(x);
Linus Torvalds1da177e2005-04-16 15:20:36 -070088 struct xfrm_state *t = NULL;
89
Alexey Dobriyand74340d2010-01-25 10:39:09 +000090 t = xfrm_state_alloc(net);
Linus Torvalds1da177e2005-04-16 15:20:36 -070091 if (!t)
92 goto out;
93
94 t->id.proto = IPPROTO_IPV6;
Alexey Dobriyand74340d2010-01-25 10:39:09 +000095 t->id.spi = xfrm6_tunnel_alloc_spi(net, (xfrm_address_t *)&x->props.saddr);
Herbert Xu6abaaaa2006-03-26 17:37:54 -080096 if (!t->id.spi)
97 goto error;
98
Linus Torvalds1da177e2005-04-16 15:20:36 -070099 memcpy(t->id.daddr.a6, x->id.daddr.a6, sizeof(struct in6_addr));
100 memcpy(&t->sel, &x->sel, sizeof(t->sel));
101 t->props.family = AF_INET6;
Herbert Xue40b3282007-11-13 21:39:08 -0800102 t->props.mode = x->props.mode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700103 memcpy(t->props.saddr.a6, x->props.saddr.a6, sizeof(struct in6_addr));
Jamal Hadi Salimbd557752010-02-22 16:20:22 -0800104 memcpy(&t->mark, &x->mark, sizeof(t->mark));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105
Herbert Xu72cb6962005-06-20 13:18:08 -0700106 if (xfrm_init_state(t))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700107 goto error;
108
Linus Torvalds1da177e2005-04-16 15:20:36 -0700109 atomic_set(&t->tunnel_users, 1);
110
111out:
112 return t;
113
114error:
Herbert Xu6abaaaa2006-03-26 17:37:54 -0800115 t->km.state = XFRM_STATE_DEAD;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 xfrm_state_put(t);
Herbert Xu6abaaaa2006-03-26 17:37:54 -0800117 t = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 goto out;
119}
120
121static int ipcomp6_tunnel_attach(struct xfrm_state *x)
122{
Alexey Dobriyand74340d2010-01-25 10:39:09 +0000123 struct net *net = xs_net(x);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124 int err = 0;
125 struct xfrm_state *t = NULL;
Al Viroa94cfd12006-09-27 18:47:24 -0700126 __be32 spi;
Jamal Hadi Salimbd557752010-02-22 16:20:22 -0800127 u32 mark = x->mark.m & x->mark.v;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700128
Alexey Dobriyand74340d2010-01-25 10:39:09 +0000129 spi = xfrm6_tunnel_spi_lookup(net, (xfrm_address_t *)&x->props.saddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130 if (spi)
Jamal Hadi Salimbd557752010-02-22 16:20:22 -0800131 t = xfrm_state_lookup(net, mark, (xfrm_address_t *)&x->id.daddr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132 spi, IPPROTO_IPV6, AF_INET6);
133 if (!t) {
134 t = ipcomp6_tunnel_create(x);
135 if (!t) {
136 err = -EINVAL;
137 goto out;
138 }
139 xfrm_state_insert(t);
140 xfrm_state_hold(t);
141 }
142 x->tunnel = t;
143 atomic_inc(&t->tunnel_users);
144
145out:
146 return err;
147}
148
Herbert Xu72cb6962005-06-20 13:18:08 -0700149static int ipcomp6_init_state(struct xfrm_state *x)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150{
David S. Miller2c3abab2008-07-27 03:59:24 -0700151 int err = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 x->props.header_len = 0;
Herbert Xuca681452007-10-17 21:35:15 -0700154 switch (x->props.mode) {
Herbert Xuca681452007-10-17 21:35:15 -0700155 case XFRM_MODE_TRANSPORT:
156 break;
157 case XFRM_MODE_TUNNEL:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158 x->props.header_len += sizeof(struct ipv6hdr);
Herbert Xue40b3282007-11-13 21:39:08 -0800159 break;
Herbert Xuca681452007-10-17 21:35:15 -0700160 default:
Herbert Xue40b3282007-11-13 21:39:08 -0800161 goto out;
Herbert Xuca681452007-10-17 21:35:15 -0700162 }
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900163
Herbert Xu6fccab62008-07-25 02:54:40 -0700164 err = ipcomp_init_state(x);
165 if (err)
Herbert Xue40b3282007-11-13 21:39:08 -0800166 goto out;
167
Masahide NAKAMURA7e49e6d2006-09-22 15:05:15 -0700168 if (x->props.mode == XFRM_MODE_TUNNEL) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700169 err = ipcomp6_tunnel_attach(x);
170 if (err)
Herbert Xu10e74542010-02-15 19:24:30 +0000171 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 }
173
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174 err = 0;
175out:
176 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177}
178
Eric Dumazet533cb5b2008-01-30 19:11:50 -0800179static const struct xfrm_type ipcomp6_type =
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180{
181 .description = "IPCOMP6",
182 .owner = THIS_MODULE,
183 .proto = IPPROTO_COMP,
184 .init_state = ipcomp6_init_state,
Herbert Xu6fccab62008-07-25 02:54:40 -0700185 .destructor = ipcomp_destroy,
186 .input = ipcomp_input,
187 .output = ipcomp_output,
Masahide NAKAMURAaee5adb2006-08-23 17:57:28 -0700188 .hdr_offset = xfrm6_find_1stfragopt,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189};
190
Alexey Dobriyan41135cc2009-09-14 12:22:28 +0000191static const struct inet6_protocol ipcomp6_protocol =
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192{
193 .handler = xfrm6_rcv,
194 .err_handler = ipcomp6_err,
195 .flags = INET6_PROTO_NOPOLICY,
196};
197
198static int __init ipcomp6_init(void)
199{
200 if (xfrm_register_type(&ipcomp6_type, AF_INET6) < 0) {
Joe Perchesf3213832012-05-15 14:11:53 +0000201 pr_info("%s: can't add xfrm type\n", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202 return -EAGAIN;
203 }
204 if (inet6_add_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0) {
Joe Perchesf3213832012-05-15 14:11:53 +0000205 pr_info("%s: can't add protocol\n", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206 xfrm_unregister_type(&ipcomp6_type, AF_INET6);
207 return -EAGAIN;
208 }
209 return 0;
210}
211
212static void __exit ipcomp6_fini(void)
213{
YOSHIFUJI Hideaki1ab14572007-02-09 23:24:49 +0900214 if (inet6_del_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0)
Joe Perchesf3213832012-05-15 14:11:53 +0000215 pr_info("%s: can't remove protocol\n", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216 if (xfrm_unregister_type(&ipcomp6_type, AF_INET6) < 0)
Joe Perchesf3213832012-05-15 14:11:53 +0000217 pr_info("%s: can't remove xfrm type\n", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218}
219
220module_init(ipcomp6_init);
221module_exit(ipcomp6_fini);
222MODULE_LICENSE("GPL");
223MODULE_DESCRIPTION("IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173");
224MODULE_AUTHOR("Mitsuru KANDA <mk@linux-ipv6.org>");
225
Masahide NAKAMURAd3d6dd32007-06-26 23:57:49 -0700226MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_COMP);