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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 struct net *net = dev_net(skb->dev);
57 __be32 spi;
58 const struct ipv6hdr *iph = (const struct ipv6hdr *)skb->data;
59 struct ip_comp_hdr *ipcomph =
60 (struct ip_comp_hdr *)(skb->data + offset);
61 struct xfrm_state *x;
62
63 if (type != ICMPV6_DEST_UNREACH && type != ICMPV6_PKT_TOOBIG)
64 return;
65
66 spi = htonl(ntohs(ipcomph->cpi));
67 x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr,
68 spi, IPPROTO_COMP, AF_INET6);
69 if (!x)
70 return;
71
72 printk(KERN_DEBUG "pmtu discovery on SA IPCOMP/%08x/%pI6\n",
73 spi, &iph->daddr);
74 xfrm_state_put(x);
75}
76
77static struct xfrm_state *ipcomp6_tunnel_create(struct xfrm_state *x)
78{
79 struct net *net = xs_net(x);
80 struct xfrm_state *t = NULL;
81
82 t = xfrm_state_alloc(net);
83 if (!t)
84 goto out;
85
86 t->id.proto = IPPROTO_IPV6;
87 t->id.spi = xfrm6_tunnel_alloc_spi(net, (xfrm_address_t *)&x->props.saddr);
88 if (!t->id.spi)
89 goto error;
90
91 memcpy(t->id.daddr.a6, x->id.daddr.a6, sizeof(struct in6_addr));
92 memcpy(&t->sel, &x->sel, sizeof(t->sel));
93 t->props.family = AF_INET6;
94 t->props.mode = x->props.mode;
95 memcpy(t->props.saddr.a6, x->props.saddr.a6, sizeof(struct in6_addr));
96 memcpy(&t->mark, &x->mark, sizeof(t->mark));
97
98 if (xfrm_init_state(t))
99 goto error;
100
101 atomic_set(&t->tunnel_users, 1);
102
103out:
104 return t;
105
106error:
107 t->km.state = XFRM_STATE_DEAD;
108 xfrm_state_put(t);
109 t = NULL;
110 goto out;
111}
112
113static int ipcomp6_tunnel_attach(struct xfrm_state *x)
114{
115 struct net *net = xs_net(x);
116 int err = 0;
117 struct xfrm_state *t = NULL;
118 __be32 spi;
119 u32 mark = x->mark.m & x->mark.v;
120
121 spi = xfrm6_tunnel_spi_lookup(net, (xfrm_address_t *)&x->props.saddr);
122 if (spi)
123 t = xfrm_state_lookup(net, mark, (xfrm_address_t *)&x->id.daddr,
124 spi, IPPROTO_IPV6, AF_INET6);
125 if (!t) {
126 t = ipcomp6_tunnel_create(x);
127 if (!t) {
128 err = -EINVAL;
129 goto out;
130 }
131 xfrm_state_insert(t);
132 xfrm_state_hold(t);
133 }
134 x->tunnel = t;
135 atomic_inc(&t->tunnel_users);
136
137out:
138 return err;
139}
140
141static int ipcomp6_init_state(struct xfrm_state *x)
142{
143 int err = -EINVAL;
144
145 x->props.header_len = 0;
146 switch (x->props.mode) {
147 case XFRM_MODE_TRANSPORT:
148 break;
149 case XFRM_MODE_TUNNEL:
150 x->props.header_len += sizeof(struct ipv6hdr);
151 break;
152 default:
153 goto out;
154 }
155
156 err = ipcomp_init_state(x);
157 if (err)
158 goto out;
159
160 if (x->props.mode == XFRM_MODE_TUNNEL) {
161 err = ipcomp6_tunnel_attach(x);
162 if (err)
163 goto out;
164 }
165
166 err = 0;
167out:
168 return err;
169}
170
171static const struct xfrm_type ipcomp6_type =
172{
173 .description = "IPCOMP6",
174 .owner = THIS_MODULE,
175 .proto = IPPROTO_COMP,
176 .init_state = ipcomp6_init_state,
177 .destructor = ipcomp_destroy,
178 .input = ipcomp_input,
179 .output = ipcomp_output,
180 .hdr_offset = xfrm6_find_1stfragopt,
181};
182
183static const struct inet6_protocol ipcomp6_protocol =
184{
185 .handler = xfrm6_rcv,
186 .err_handler = ipcomp6_err,
187 .flags = INET6_PROTO_NOPOLICY,
188};
189
190static int __init ipcomp6_init(void)
191{
192 if (xfrm_register_type(&ipcomp6_type, AF_INET6) < 0) {
193 printk(KERN_INFO "ipcomp6 init: can't add xfrm type\n");
194 return -EAGAIN;
195 }
196 if (inet6_add_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0) {
197 printk(KERN_INFO "ipcomp6 init: can't add protocol\n");
198 xfrm_unregister_type(&ipcomp6_type, AF_INET6);
199 return -EAGAIN;
200 }
201 return 0;
202}
203
204static void __exit ipcomp6_fini(void)
205{
206 if (inet6_del_protocol(&ipcomp6_protocol, IPPROTO_COMP) < 0)
207 printk(KERN_INFO "ipv6 ipcomp close: can't remove protocol\n");
208 if (xfrm_unregister_type(&ipcomp6_type, AF_INET6) < 0)
209 printk(KERN_INFO "ipv6 ipcomp close: can't remove xfrm type\n");
210}
211
212module_init(ipcomp6_init);
213module_exit(ipcomp6_fini);
214MODULE_LICENSE("GPL");
215MODULE_DESCRIPTION("IP Payload Compression Protocol (IPComp) for IPv6 - RFC3173");
216MODULE_AUTHOR("Mitsuru KANDA <mk@linux-ipv6.org>");
217
218MODULE_ALIAS_XFRM_TYPE(AF_INET6, XFRM_PROTO_COMP);
219
