2 * IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173
4 * Copyright (C)2003 USAGI/WIDE Project
6 * Author Mitsuru KANDA <mk@linux-ipv6.org>
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.
13 * 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.
18 * 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
26 * The compression of IP datagram MUST be done before AH/ESP processing,
27 * fragmentation, and the addition of Hop-by-Hop/Routing header.
30 * The decompression of IP datagram MUST be done after the reassembly,
34 #define pr_fmt(fmt) "IPv6: " fmt
36 #include <linux/module.h>
39 #include <net/ipcomp.h>
40 #include <linux/crypto.h>
41 #include <linux/err.h>
42 #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>
49 #include <net/ip6_route.h>
52 #include <net/protocol.h>
53 #include <linux/ipv6.h>
54 #include <linux/icmpv6.h>
55 #include <linux/mutex.h>
57 static void ipcomp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
58 u8 type, u8 code, int offset, __be32 info)
60 struct net *net = dev_net(skb->dev);
62 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
63 struct ip_comp_hdr *ipcomph =
64 (struct ip_comp_hdr *)(skb->data + offset);
67 if (type != ICMPV6_DEST_UNREACH && type != ICMPV6_PKT_TOOBIG)
70 spi = htonl(ntohs(ipcomph->cpi));
71 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
72 spi, IPPROTO_COMP, AF_INET6);
76 pr_debug("pmtu discovery on SA IPCOMP/%08x/%pI6\n",
78 ip6_update_pmtu(skb, net, info, 0, 0);
82 static struct xfrm_state *ipcomp6_tunnel_create(struct xfrm_state *x)
84 struct net *net = xs_net(x);
85 struct xfrm_state *t = NULL;
87 t = xfrm_state_alloc(net);
91 t->id.proto = IPPROTO_IPV6;
92 t->id.spi = xfrm6_tunnel_alloc_spi(net, (xfrm_address_t *)&x->props.saddr);
96 memcpy(t->id.daddr.a6, x->id.daddr.a6, sizeof(struct in6_addr));
97 memcpy(&t->sel, &x->sel, sizeof(t->sel));
98 t->props.family = AF_INET6;
99 t->props.mode = x->props.mode;
100 memcpy(t->props.saddr.a6, x->props.saddr.a6, sizeof(struct in6_addr));
101 memcpy(&t->mark, &x->mark, sizeof(t->mark));
103 if (xfrm_init_state(t))
106 atomic_set(&t->tunnel_users, 1);
112 t->km.state = XFRM_STATE_DEAD;
118 static int ipcomp6_tunnel_attach(struct xfrm_state *x)
120 struct net *net = xs_net(x);
122 struct xfrm_state *t = NULL;
124 u32 mark = x->mark.m & x->mark.v;
126 spi = xfrm6_tunnel_spi_lookup(net, (xfrm_address_t *)&x->props.saddr);
128 t = xfrm_state_lookup(net, mark, (xfrm_address_t *)&x->id.daddr,
129 spi, IPPROTO_IPV6, AF_INET6);
131 t = ipcomp6_tunnel_create(x);
136 xfrm_state_insert(t);
140 atomic_inc(&t->tunnel_users);
146 static int ipcomp6_init_state(struct xfrm_state *x)
150 x->props.header_len = 0;
151 switch (x->props.mode) {
152 case XFRM_MODE_TRANSPORT:
154 case XFRM_MODE_TUNNEL:
155 x->props.header_len += sizeof(struct ipv6hdr);
161 err = ipcomp_init_state(x);
165 if (x->props.mode == XFRM_MODE_TUNNEL) {
166 err = ipcomp6_tunnel_attach(x);
176 static const struct xfrm_type ipcomp6_type =
178 .description = "IPCOMP6",
179 .owner = THIS_MODULE,
180 .proto = IPPROTO_COMP,
181 .init_state = ipcomp6_init_state,
182 .destructor = ipcomp_destroy,
183 .input = ipcomp_input,
184 .output = ipcomp_output,
185 .hdr_offset = xfrm6_find_1stfragopt,
188 static const struct inet6_protocol ipcomp6_protocol =
190 .handler = xfrm6_rcv,
191 .err_handler = ipcomp6_err,
192 .flags = INET6_PROTO_NOPOLICY,
195 static int __init ipcomp6_init(void)
197 if (xfrm_register_type(&ipcomp6_type, AF_INET6) < 0) {
198 pr_info("%s: can't add xfrm type\n", __func__);
201 if (inet6_add_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0) {
202 pr_info("%s: can't add protocol\n", __func__);
203 xfrm_unregister_type(&ipcomp6_type, AF_INET6);
209 static void __exit ipcomp6_fini(void)
211 if (inet6_del_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0)
212 pr_info("%s: can't remove protocol\n", __func__);
213 if (xfrm_unregister_type(&ipcomp6_type, AF_INET6) < 0)
214 pr_info("%s: can't remove xfrm type\n", __func__);
217 module_init(ipcomp6_init);
218 module_exit(ipcomp6_fini);
219 MODULE_LICENSE("GPL");
220 MODULE_DESCRIPTION("IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173");
221 MODULE_AUTHOR("Mitsuru KANDA <mk@linux-ipv6.org>");
223 MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_COMP);