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33#include <linux/module.h>
34#include <net/ip.h>
35#include <net/xfrm.h>
36#include <net/ipcomp.h>
37#include <linux/crypto.h>
38#include <linux/err.h>
39#include <linux/pfkeyv2.h>
40#include <linux/random.h>
41#include <linux/percpu.h>
42#include <linux/smp.h>
43#include <linux/list.h>
44#include <linux/vmalloc.h>
45#include <linux/rtnetlink.h>
46#include <net/icmp.h>
47#include <net/ipv6.h>
48#include <net/protocol.h>
49#include <linux/ipv6.h>
50#include <linux/icmpv6.h>
51#include <linux/mutex.h>
52
53static void ipcomp6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
54 u8 type, u8 code, int offset, __be32 info)
55{
56 __be32 spi;
57 struct ipv6hdr *iph = (struct ipv6hdr*)skb->data;
58 struct ip_comp_hdr *ipcomph =
59 (struct ip_comp_hdr *)(skb->data + offset);
60 struct xfrm_state *x;
61
62 if (type != ICMPV6_DEST_UNREACH && type != ICMPV6_PKT_TOOBIG)
63 return;
64
65 spi = htonl(ntohs(ipcomph->cpi));
66 x = xfrm_state_lookup(&init_net, (xfrm_address_t *)&iph->daddr, spi, IPPROTO_COMP, AF_INET6);
67 if (!x)
68 return;
69
70 printk(KERN_DEBUG "pmtu discovery on SA IPCOMP/%08x/%pI6\n",
71 spi, &iph->daddr);
72 xfrm_state_put(x);
73}
74
75static struct xfrm_state *ipcomp6_tunnel_create(struct xfrm_state *x)
76{
77 struct xfrm_state *t = NULL;
78
79 t = xfrm_state_alloc(&init_net);
80 if (!t)
81 goto out;
82
83 t->id.proto = IPPROTO_IPV6;
84 t->id.spi = xfrm6_tunnel_alloc_spi((xfrm_address_t *)&x->props.saddr);
85 if (!t->id.spi)
86 goto error;
87
88 memcpy(t->id.daddr.a6, x->id.daddr.a6, sizeof(struct in6_addr));
89 memcpy(&t->sel, &x->sel, sizeof(t->sel));
90 t->props.family = AF_INET6;
91 t->props.mode = x->props.mode;
92 memcpy(t->props.saddr.a6, x->props.saddr.a6, sizeof(struct in6_addr));
93
94 if (xfrm_init_state(t))
95 goto error;
96
97 atomic_set(&t->tunnel_users, 1);
98
99out:
100 return t;
101
102error:
103 t->km.state = XFRM_STATE_DEAD;
104 xfrm_state_put(t);
105 t = NULL;
106 goto out;
107}
108
109static int ipcomp6_tunnel_attach(struct xfrm_state *x)
110{
111 int err = 0;
112 struct xfrm_state *t = NULL;
113 __be32 spi;
114
115 spi = xfrm6_tunnel_spi_lookup((xfrm_address_t *)&x->props.saddr);
116 if (spi)
117 t = xfrm_state_lookup(&init_net, (xfrm_address_t *)&x->id.daddr,
118 spi, IPPROTO_IPV6, AF_INET6);
119 if (!t) {
120 t = ipcomp6_tunnel_create(x);
121 if (!t) {
122 err = -EINVAL;
123 goto out;
124 }
125 xfrm_state_insert(t);
126 xfrm_state_hold(t);
127 }
128 x->tunnel = t;
129 atomic_inc(&t->tunnel_users);
130
131out:
132 return err;
133}
134
135static int ipcomp6_init_state(struct xfrm_state *x)
136{
137 int err = -EINVAL;
138
139 x->props.header_len = 0;
140 switch (x->props.mode) {
141 case XFRM_MODE_TRANSPORT:
142 break;
143 case XFRM_MODE_TUNNEL:
144 x->props.header_len += sizeof(struct ipv6hdr);
145 break;
146 default:
147 goto out;
148 }
149
150 err = ipcomp_init_state(x);
151 if (err)
152 goto out;
153
154 if (x->props.mode == XFRM_MODE_TUNNEL) {
155 err = ipcomp6_tunnel_attach(x);
156 if (err)
157 goto error_tunnel;
158 }
159
160 err = 0;
161out:
162 return err;
163error_tunnel:
164 ipcomp_destroy(x);
165
166 goto out;
167}
168
169static const struct xfrm_type ipcomp6_type =
170{
171 .description = "IPCOMP6",
172 .owner = THIS_MODULE,
173 .proto = IPPROTO_COMP,
174 .init_state = ipcomp6_init_state,
175 .destructor = ipcomp_destroy,
176 .input = ipcomp_input,
177 .output = ipcomp_output,
178 .hdr_offset = xfrm6_find_1stfragopt,
179};
180
181static const struct inet6_protocol ipcomp6_protocol =
182{
183 .handler = xfrm6_rcv,
184 .err_handler = ipcomp6_err,
185 .flags = INET6_PROTO_NOPOLICY,
186};
187
188static int __init ipcomp6_init(void)
189{
190 if (xfrm_register_type(&ipcomp6_type, AF_INET6) < 0) {
191 printk(KERN_INFO "ipcomp6 init: can't add xfrm type\n");
192 return -EAGAIN;
193 }
194 if (inet6_add_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0) {
195 printk(KERN_INFO "ipcomp6 init: can't add protocol\n");
196 xfrm_unregister_type(&ipcomp6_type, AF_INET6);
197 return -EAGAIN;
198 }
199 return 0;
200}
201
202static void __exit ipcomp6_fini(void)
203{
204 if (inet6_del_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0)
205 printk(KERN_INFO "ipv6 ipcomp close: can't remove protocol\n");
206 if (xfrm_unregister_type(&ipcomp6_type, AF_INET6) < 0)
207 printk(KERN_INFO "ipv6 ipcomp close: can't remove xfrm type\n");
208}
209
210module_init(ipcomp6_init);
211module_exit(ipcomp6_fini);
212MODULE_LICENSE("GPL");
213MODULE_DESCRIPTION("IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173");
214MODULE_AUTHOR("Mitsuru KANDA <mk@linux-ipv6.org>");
215
216MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_COMP);
217
