security: remove the security_netlink_recv hook as it is equivalent to capable()
[linux-2.6.git] / net / ipv6 / inet6_connection_sock.c
1 /*
2  * INET        An implementation of the TCP/IP protocol suite for the LINUX
3  *             operating system.  INET is implemented using the  BSD Socket
4  *             interface as the means of communication with the user level.
5  *
6  *             Support for INET6 connection oriented protocols.
7  *
8  * Authors:    See the TCPv6 sources
9  *
10  *             This program is free software; you can redistribute it and/or
11  *             modify it under the terms of the GNU General Public License
12  *             as published by the Free Software Foundation; either version
13  *             2 of the License, or(at your option) any later version.
14  */
15
16 #include <linux/module.h>
17 #include <linux/in6.h>
18 #include <linux/ipv6.h>
19 #include <linux/jhash.h>
20 #include <linux/slab.h>
21
22 #include <net/addrconf.h>
23 #include <net/inet_connection_sock.h>
24 #include <net/inet_ecn.h>
25 #include <net/inet_hashtables.h>
26 #include <net/ip6_route.h>
27 #include <net/sock.h>
28 #include <net/inet6_connection_sock.h>
29
30 int inet6_csk_bind_conflict(const struct sock *sk,
31                             const struct inet_bind_bucket *tb)
32 {
33         const struct sock *sk2;
34         const struct hlist_node *node;
35
36         /* We must walk the whole port owner list in this case. -DaveM */
37         /*
38          * See comment in inet_csk_bind_conflict about sock lookup
39          * vs net namespaces issues.
40          */
41         sk_for_each_bound(sk2, node, &tb->owners) {
42                 if (sk != sk2 &&
43                     (!sk->sk_bound_dev_if ||
44                      !sk2->sk_bound_dev_if ||
45                      sk->sk_bound_dev_if == sk2->sk_bound_dev_if) &&
46                     (!sk->sk_reuse || !sk2->sk_reuse ||
47                      sk2->sk_state == TCP_LISTEN) &&
48                      ipv6_rcv_saddr_equal(sk, sk2))
49                         break;
50         }
51
52         return node != NULL;
53 }
54
55 EXPORT_SYMBOL_GPL(inet6_csk_bind_conflict);
56
57 struct dst_entry *inet6_csk_route_req(struct sock *sk,
58                                       const struct request_sock *req)
59 {
60         struct inet6_request_sock *treq = inet6_rsk(req);
61         struct ipv6_pinfo *np = inet6_sk(sk);
62         struct in6_addr *final_p, final;
63         struct dst_entry *dst;
64         struct flowi6 fl6;
65
66         memset(&fl6, 0, sizeof(fl6));
67         fl6.flowi6_proto = IPPROTO_TCP;
68         ipv6_addr_copy(&fl6.daddr, &treq->rmt_addr);
69         final_p = fl6_update_dst(&fl6, np->opt, &final);
70         ipv6_addr_copy(&fl6.saddr, &treq->loc_addr);
71         fl6.flowi6_oif = sk->sk_bound_dev_if;
72         fl6.flowi6_mark = sk->sk_mark;
73         fl6.fl6_dport = inet_rsk(req)->rmt_port;
74         fl6.fl6_sport = inet_rsk(req)->loc_port;
75         security_req_classify_flow(req, flowi6_to_flowi(&fl6));
76
77         dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
78         if (IS_ERR(dst))
79                 return NULL;
80
81         return dst;
82 }
83
84 /*
85  * request_sock (formerly open request) hash tables.
86  */
87 static u32 inet6_synq_hash(const struct in6_addr *raddr, const __be16 rport,
88                            const u32 rnd, const u16 synq_hsize)
89 {
90         u32 c;
91
92         c = jhash_3words((__force u32)raddr->s6_addr32[0],
93                          (__force u32)raddr->s6_addr32[1],
94                          (__force u32)raddr->s6_addr32[2],
95                          rnd);
96
97         c = jhash_2words((__force u32)raddr->s6_addr32[3],
98                          (__force u32)rport,
99                          c);
100
101         return c & (synq_hsize - 1);
102 }
103
104 struct request_sock *inet6_csk_search_req(const struct sock *sk,
105                                           struct request_sock ***prevp,
106                                           const __be16 rport,
107                                           const struct in6_addr *raddr,
108                                           const struct in6_addr *laddr,
109                                           const int iif)
110 {
111         const struct inet_connection_sock *icsk = inet_csk(sk);
112         struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
113         struct request_sock *req, **prev;
114
115         for (prev = &lopt->syn_table[inet6_synq_hash(raddr, rport,
116                                                      lopt->hash_rnd,
117                                                      lopt->nr_table_entries)];
118              (req = *prev) != NULL;
119              prev = &req->dl_next) {
120                 const struct inet6_request_sock *treq = inet6_rsk(req);
121
122                 if (inet_rsk(req)->rmt_port == rport &&
123                     req->rsk_ops->family == AF_INET6 &&
124                     ipv6_addr_equal(&treq->rmt_addr, raddr) &&
125                     ipv6_addr_equal(&treq->loc_addr, laddr) &&
126                     (!treq->iif || treq->iif == iif)) {
127                         WARN_ON(req->sk != NULL);
128                         *prevp = prev;
129                         return req;
130                 }
131         }
132
133         return NULL;
134 }
135
136 EXPORT_SYMBOL_GPL(inet6_csk_search_req);
137
138 void inet6_csk_reqsk_queue_hash_add(struct sock *sk,
139                                     struct request_sock *req,
140                                     const unsigned long timeout)
141 {
142         struct inet_connection_sock *icsk = inet_csk(sk);
143         struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
144         const u32 h = inet6_synq_hash(&inet6_rsk(req)->rmt_addr,
145                                       inet_rsk(req)->rmt_port,
146                                       lopt->hash_rnd, lopt->nr_table_entries);
147
148         reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout);
149         inet_csk_reqsk_queue_added(sk, timeout);
150 }
151
152 EXPORT_SYMBOL_GPL(inet6_csk_reqsk_queue_hash_add);
153
154 void inet6_csk_addr2sockaddr(struct sock *sk, struct sockaddr * uaddr)
155 {
156         struct ipv6_pinfo *np = inet6_sk(sk);
157         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) uaddr;
158
159         sin6->sin6_family = AF_INET6;
160         ipv6_addr_copy(&sin6->sin6_addr, &np->daddr);
161         sin6->sin6_port = inet_sk(sk)->inet_dport;
162         /* We do not store received flowlabel for TCP */
163         sin6->sin6_flowinfo = 0;
164         sin6->sin6_scope_id = 0;
165         if (sk->sk_bound_dev_if &&
166             ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
167                 sin6->sin6_scope_id = sk->sk_bound_dev_if;
168 }
169
170 EXPORT_SYMBOL_GPL(inet6_csk_addr2sockaddr);
171
172 static inline
173 void __inet6_csk_dst_store(struct sock *sk, struct dst_entry *dst,
174                            struct in6_addr *daddr, struct in6_addr *saddr)
175 {
176         __ip6_dst_store(sk, dst, daddr, saddr);
177
178 #ifdef CONFIG_XFRM
179         {
180                 struct rt6_info *rt = (struct rt6_info  *)dst;
181                 rt->rt6i_flow_cache_genid = atomic_read(&flow_cache_genid);
182         }
183 #endif
184 }
185
186 static inline
187 struct dst_entry *__inet6_csk_dst_check(struct sock *sk, u32 cookie)
188 {
189         struct dst_entry *dst;
190
191         dst = __sk_dst_check(sk, cookie);
192
193 #ifdef CONFIG_XFRM
194         if (dst) {
195                 struct rt6_info *rt = (struct rt6_info *)dst;
196                 if (rt->rt6i_flow_cache_genid != atomic_read(&flow_cache_genid)) {
197                         __sk_dst_reset(sk);
198                         dst = NULL;
199                 }
200         }
201 #endif
202
203         return dst;
204 }
205
206 int inet6_csk_xmit(struct sk_buff *skb, struct flowi *fl_unused)
207 {
208         struct sock *sk = skb->sk;
209         struct inet_sock *inet = inet_sk(sk);
210         struct ipv6_pinfo *np = inet6_sk(sk);
211         struct flowi6 fl6;
212         struct dst_entry *dst;
213         struct in6_addr *final_p, final;
214
215         memset(&fl6, 0, sizeof(fl6));
216         fl6.flowi6_proto = sk->sk_protocol;
217         ipv6_addr_copy(&fl6.daddr, &np->daddr);
218         ipv6_addr_copy(&fl6.saddr, &np->saddr);
219         fl6.flowlabel = np->flow_label;
220         IP6_ECN_flow_xmit(sk, fl6.flowlabel);
221         fl6.flowi6_oif = sk->sk_bound_dev_if;
222         fl6.flowi6_mark = sk->sk_mark;
223         fl6.fl6_sport = inet->inet_sport;
224         fl6.fl6_dport = inet->inet_dport;
225         security_sk_classify_flow(sk, flowi6_to_flowi(&fl6));
226
227         final_p = fl6_update_dst(&fl6, np->opt, &final);
228
229         dst = __inet6_csk_dst_check(sk, np->dst_cookie);
230
231         if (dst == NULL) {
232                 dst = ip6_dst_lookup_flow(sk, &fl6, final_p, false);
233
234                 if (IS_ERR(dst)) {
235                         sk->sk_err_soft = -PTR_ERR(dst);
236                         sk->sk_route_caps = 0;
237                         kfree_skb(skb);
238                         return PTR_ERR(dst);
239                 }
240
241                 __inet6_csk_dst_store(sk, dst, NULL, NULL);
242         }
243
244         skb_dst_set(skb, dst_clone(dst));
245
246         /* Restore final destination back after routing done */
247         ipv6_addr_copy(&fl6.daddr, &np->daddr);
248
249         return ip6_xmit(sk, skb, &fl6, np->opt);
250 }
251
252 EXPORT_SYMBOL_GPL(inet6_csk_xmit);