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