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33#define pr_fmt(fmt) "IPv6: " fmt
34
35#include <linux/module.h>
36#include <net/ip.h>
37#include <net/xfrm.h>
38#include <net/ipcomp.h>
39#include <linux/crypto.h>
40#include <linux/err.h>
41#include <linux/pfkeyv2.h>
42#include <linux/random.h>
43#include <linux/percpu.h>
44#include <linux/smp.h>
45#include <linux/list.h>
46#include <linux/vmalloc.h>
47#include <linux/rtnetlink.h>
48#include <net/ip6_route.h>
49#include <net/icmp.h>
50#include <net/ipv6.h>
51#include <net/protocol.h>
52#include <linux/ipv6.h>
53#include <linux/icmpv6.h>
54#include <linux/mutex.h>
55
56static int ipcomp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
57 u8 type, u8 code, int offset, __be32 info)
58{
59 struct net *net = dev_net(skb->dev);
60 __be32 spi;
61 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
62 struct ip_comp_hdr *ipcomph =
63 (struct ip_comp_hdr *)(skb->data + offset);
64 struct xfrm_state *x;
65
66 if (type != ICMPV6_PKT_TOOBIG &&
67 type != NDISC_REDIRECT)
68 return 0;
69
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);
73 if (!x)
74 return 0;
75
76 if (type == NDISC_REDIRECT)
77 ip6_redirect(skb, net, skb->dev->ifindex, 0,
78 sock_net_uid(net, NULL));
79 else
80 ip6_update_pmtu(skb, net, info, 0, 0, sock_net_uid(net, NULL));
81 xfrm_state_put(x);
82
83 return 0;
84}
85
86static struct xfrm_state *ipcomp6_tunnel_create(struct xfrm_state *x)
87{
88 struct net *net = xs_net(x);
89 struct xfrm_state *t = NULL;
90
91 t = xfrm_state_alloc(net);
92 if (!t)
93 goto out;
94
95 t->id.proto = IPPROTO_IPV6;
96 t->id.spi = xfrm6_tunnel_alloc_spi(net, (xfrm_address_t *)&x->props.saddr);
97 if (!t->id.spi)
98 goto error;
99
100 memcpy(t->id.daddr.a6, x->id.daddr.a6, sizeof(struct in6_addr));
101 memcpy(&t->sel, &x->sel, sizeof(t->sel));
102 t->props.family = AF_INET6;
103 t->props.mode = x->props.mode;
104 memcpy(t->props.saddr.a6, x->props.saddr.a6, sizeof(struct in6_addr));
105 memcpy(&t->mark, &x->mark, sizeof(t->mark));
106
107 if (xfrm_init_state(t))
108 goto error;
109
110 atomic_set(&t->tunnel_users, 1);
111
112out:
113 return t;
114
115error:
116 t->km.state = XFRM_STATE_DEAD;
117 xfrm_state_put(t);
118 t = NULL;
119 goto out;
120}
121
122static int ipcomp6_tunnel_attach(struct xfrm_state *x)
123{
124 struct net *net = xs_net(x);
125 int err = 0;
126 struct xfrm_state *t = NULL;
127 __be32 spi;
128 u32 mark = x->mark.m & x->mark.v;
129
130 spi = xfrm6_tunnel_spi_lookup(net, (xfrm_address_t *)&x->props.saddr);
131 if (spi)
132 t = xfrm_state_lookup(net, mark, (xfrm_address_t *)&x->id.daddr,
133 spi, IPPROTO_IPV6, AF_INET6);
134 if (!t) {
135 t = ipcomp6_tunnel_create(x);
136 if (!t) {
137 err = -EINVAL;
138 goto out;
139 }
140 xfrm_state_insert(t);
141 xfrm_state_hold(t);
142 }
143 x->tunnel = t;
144 atomic_inc(&t->tunnel_users);
145
146out:
147 return err;
148}
149
150static int ipcomp6_init_state(struct xfrm_state *x)
151{
152 int err = -EINVAL;
153
154 x->props.header_len = 0;
155 switch (x->props.mode) {
156 case XFRM_MODE_TRANSPORT:
157 break;
158 case XFRM_MODE_TUNNEL:
159 x->props.header_len += sizeof(struct ipv6hdr);
160 break;
161 default:
162 goto out;
163 }
164
165 err = ipcomp_init_state(x);
166 if (err)
167 goto out;
168
169 if (x->props.mode == XFRM_MODE_TUNNEL) {
170 err = ipcomp6_tunnel_attach(x);
171 if (err)
172 goto out;
173 }
174
175 err = 0;
176out:
177 return err;
178}
179
180static int ipcomp6_rcv_cb(struct sk_buff *skb, int err)
181{
182 return 0;
183}
184
185static const struct xfrm_type ipcomp6_type = {
186 .description = "IPCOMP6",
187 .owner = THIS_MODULE,
188 .proto = IPPROTO_COMP,
189 .init_state = ipcomp6_init_state,
190 .destructor = ipcomp_destroy,
191 .input = ipcomp_input,
192 .output = ipcomp_output,
193 .hdr_offset = xfrm6_find_1stfragopt,
194};
195
196static struct xfrm6_protocol ipcomp6_protocol = {
197 .handler = xfrm6_rcv,
198 .cb_handler = ipcomp6_rcv_cb,
199 .err_handler = ipcomp6_err,
200 .priority = 0,
201};
202
203static int __init ipcomp6_init(void)
204{
205 if (xfrm_register_type(&ipcomp6_type, AF_INET6) < 0) {
206 pr_info("%s: can't add xfrm type\n", __func__);
207 return -EAGAIN;
208 }
209 if (xfrm6_protocol_register(&ipcomp6_protocol, IPPROTO_COMP) < 0) {
210 pr_info("%s: can't add protocol\n", __func__);
211 xfrm_unregister_type(&ipcomp6_type, AF_INET6);
212 return -EAGAIN;
213 }
214 return 0;
215}
216
217static void __exit ipcomp6_fini(void)
218{
219 if (xfrm6_protocol_deregister(&ipcomp6_protocol, IPPROTO_COMP) < 0)
220 pr_info("%s: can't remove protocol\n", __func__);
221 if (xfrm_unregister_type(&ipcomp6_type, AF_INET6) < 0)
222 pr_info("%s: can't remove xfrm type\n", __func__);
223}
224
225module_init(ipcomp6_init);
226module_exit(ipcomp6_fini);
227MODULE_LICENSE("GPL");
228MODULE_DESCRIPTION("IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173");
229MODULE_AUTHOR("Mitsuru KANDA <mk@linux-ipv6.org>");
230
231MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_COMP);
232
