628db24bcf22bceff783384ea7779a87c4cb0ab7
[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 /*
58  * request_sock (formerly open request) hash tables.
59  */
60 static u32 inet6_synq_hash(const struct in6_addr *raddr, const __be16 rport,
61                            const u32 rnd, const u16 synq_hsize)
62 {
63         u32 a = (__force u32)raddr->s6_addr32[0];
64         u32 b = (__force u32)raddr->s6_addr32[1];
65         u32 c = (__force u32)raddr->s6_addr32[2];
66
67         a += JHASH_GOLDEN_RATIO;
68         b += JHASH_GOLDEN_RATIO;
69         c += rnd;
70         __jhash_mix(a, b, c);
71
72         a += (__force u32)raddr->s6_addr32[3];
73         b += (__force u32)rport;
74         __jhash_mix(a, b, c);
75
76         return c & (synq_hsize - 1);
77 }
78
79 struct request_sock *inet6_csk_search_req(const struct sock *sk,
80                                           struct request_sock ***prevp,
81                                           const __be16 rport,
82                                           const struct in6_addr *raddr,
83                                           const struct in6_addr *laddr,
84                                           const int iif)
85 {
86         const struct inet_connection_sock *icsk = inet_csk(sk);
87         struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
88         struct request_sock *req, **prev;
89
90         for (prev = &lopt->syn_table[inet6_synq_hash(raddr, rport,
91                                                      lopt->hash_rnd,
92                                                      lopt->nr_table_entries)];
93              (req = *prev) != NULL;
94              prev = &req->dl_next) {
95                 const struct inet6_request_sock *treq = inet6_rsk(req);
96
97                 if (inet_rsk(req)->rmt_port == rport &&
98                     req->rsk_ops->family == AF_INET6 &&
99                     ipv6_addr_equal(&treq->rmt_addr, raddr) &&
100                     ipv6_addr_equal(&treq->loc_addr, laddr) &&
101                     (!treq->iif || treq->iif == iif)) {
102                         WARN_ON(req->sk != NULL);
103                         *prevp = prev;
104                         return req;
105                 }
106         }
107
108         return NULL;
109 }
110
111 EXPORT_SYMBOL_GPL(inet6_csk_search_req);
112
113 void inet6_csk_reqsk_queue_hash_add(struct sock *sk,
114                                     struct request_sock *req,
115                                     const unsigned long timeout)
116 {
117         struct inet_connection_sock *icsk = inet_csk(sk);
118         struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
119         const u32 h = inet6_synq_hash(&inet6_rsk(req)->rmt_addr,
120                                       inet_rsk(req)->rmt_port,
121                                       lopt->hash_rnd, lopt->nr_table_entries);
122
123         reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout);
124         inet_csk_reqsk_queue_added(sk, timeout);
125 }
126
127 EXPORT_SYMBOL_GPL(inet6_csk_reqsk_queue_hash_add);
128
129 void inet6_csk_addr2sockaddr(struct sock *sk, struct sockaddr * uaddr)
130 {
131         struct ipv6_pinfo *np = inet6_sk(sk);
132         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) uaddr;
133
134         sin6->sin6_family = AF_INET6;
135         ipv6_addr_copy(&sin6->sin6_addr, &np->daddr);
136         sin6->sin6_port = inet_sk(sk)->inet_dport;
137         /* We do not store received flowlabel for TCP */
138         sin6->sin6_flowinfo = 0;
139         sin6->sin6_scope_id = 0;
140         if (sk->sk_bound_dev_if &&
141             ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
142                 sin6->sin6_scope_id = sk->sk_bound_dev_if;
143 }
144
145 EXPORT_SYMBOL_GPL(inet6_csk_addr2sockaddr);
146
147 static inline
148 void __inet6_csk_dst_store(struct sock *sk, struct dst_entry *dst,
149                            struct in6_addr *daddr, struct in6_addr *saddr)
150 {
151         __ip6_dst_store(sk, dst, daddr, saddr);
152
153 #ifdef CONFIG_XFRM
154         {
155                 struct rt6_info *rt = (struct rt6_info  *)dst;
156                 rt->rt6i_flow_cache_genid = atomic_read(&flow_cache_genid);
157         }
158 #endif
159 }
160
161 static inline
162 struct dst_entry *__inet6_csk_dst_check(struct sock *sk, u32 cookie)
163 {
164         struct dst_entry *dst;
165
166         dst = __sk_dst_check(sk, cookie);
167
168 #ifdef CONFIG_XFRM
169         if (dst) {
170                 struct rt6_info *rt = (struct rt6_info *)dst;
171                 if (rt->rt6i_flow_cache_genid != atomic_read(&flow_cache_genid)) {
172                         __sk_dst_reset(sk);
173                         dst = NULL;
174                 }
175         }
176 #endif
177
178         return dst;
179 }
180
181 int inet6_csk_xmit(struct sk_buff *skb, int ipfragok)
182 {
183         struct sock *sk = skb->sk;
184         struct inet_sock *inet = inet_sk(sk);
185         struct ipv6_pinfo *np = inet6_sk(sk);
186         struct flowi fl;
187         struct dst_entry *dst;
188         struct in6_addr *final_p = NULL, final;
189
190         memset(&fl, 0, sizeof(fl));
191         fl.proto = sk->sk_protocol;
192         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
193         ipv6_addr_copy(&fl.fl6_src, &np->saddr);
194         fl.fl6_flowlabel = np->flow_label;
195         IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
196         fl.oif = sk->sk_bound_dev_if;
197         fl.mark = sk->sk_mark;
198         fl.fl_ip_sport = inet->inet_sport;
199         fl.fl_ip_dport = inet->inet_dport;
200         security_sk_classify_flow(sk, &fl);
201
202         if (np->opt && np->opt->srcrt) {
203                 struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
204                 ipv6_addr_copy(&final, &fl.fl6_dst);
205                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
206                 final_p = &final;
207         }
208
209         dst = __inet6_csk_dst_check(sk, np->dst_cookie);
210
211         if (dst == NULL) {
212                 int err = ip6_dst_lookup(sk, &dst, &fl);
213
214                 if (err) {
215                         sk->sk_err_soft = -err;
216                         kfree_skb(skb);
217                         return err;
218                 }
219
220                 if (final_p)
221                         ipv6_addr_copy(&fl.fl6_dst, final_p);
222
223                 if ((err = xfrm_lookup(sock_net(sk), &dst, &fl, sk, 0)) < 0) {
224                         sk->sk_route_caps = 0;
225                         kfree_skb(skb);
226                         return err;
227                 }
228
229                 __inet6_csk_dst_store(sk, dst, NULL, NULL);
230         }
231
232         skb_dst_set(skb, dst_clone(dst));
233
234         /* Restore final destination back after routing done */
235         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
236
237         return ip6_xmit(sk, skb, &fl, np->opt, 0);
238 }
239
240 EXPORT_SYMBOL_GPL(inet6_csk_xmit);