[SK_BUFF]: Introduce skb_network_header_len
[linux-2.6] / 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
21 #include <net/addrconf.h>
22 #include <net/inet_connection_sock.h>
23 #include <net/inet_ecn.h>
24 #include <net/inet_hashtables.h>
25 #include <net/ip6_route.h>
26 #include <net/sock.h>
27 #include <net/inet6_connection_sock.h>
28
29 int inet6_csk_bind_conflict(const struct sock *sk,
30                             const struct inet_bind_bucket *tb)
31 {
32         const struct sock *sk2;
33         const struct hlist_node *node;
34
35         /* We must walk the whole port owner list in this case. -DaveM */
36         sk_for_each_bound(sk2, node, &tb->owners) {
37                 if (sk != sk2 &&
38                     (!sk->sk_bound_dev_if ||
39                      !sk2->sk_bound_dev_if ||
40                      sk->sk_bound_dev_if == sk2->sk_bound_dev_if) &&
41                     (!sk->sk_reuse || !sk2->sk_reuse ||
42                      sk2->sk_state == TCP_LISTEN) &&
43                      ipv6_rcv_saddr_equal(sk, sk2))
44                         break;
45         }
46
47         return node != NULL;
48 }
49
50 EXPORT_SYMBOL_GPL(inet6_csk_bind_conflict);
51
52 /*
53  * request_sock (formerly open request) hash tables.
54  */
55 static u32 inet6_synq_hash(const struct in6_addr *raddr, const __be16 rport,
56                            const u32 rnd, const u16 synq_hsize)
57 {
58         u32 a = (__force u32)raddr->s6_addr32[0];
59         u32 b = (__force u32)raddr->s6_addr32[1];
60         u32 c = (__force u32)raddr->s6_addr32[2];
61
62         a += JHASH_GOLDEN_RATIO;
63         b += JHASH_GOLDEN_RATIO;
64         c += rnd;
65         __jhash_mix(a, b, c);
66
67         a += (__force u32)raddr->s6_addr32[3];
68         b += (__force u32)rport;
69         __jhash_mix(a, b, c);
70
71         return c & (synq_hsize - 1);
72 }
73
74 struct request_sock *inet6_csk_search_req(const struct sock *sk,
75                                           struct request_sock ***prevp,
76                                           const __be16 rport,
77                                           const struct in6_addr *raddr,
78                                           const struct in6_addr *laddr,
79                                           const int iif)
80 {
81         const struct inet_connection_sock *icsk = inet_csk(sk);
82         struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
83         struct request_sock *req, **prev;
84
85         for (prev = &lopt->syn_table[inet6_synq_hash(raddr, rport,
86                                                      lopt->hash_rnd,
87                                                      lopt->nr_table_entries)];
88              (req = *prev) != NULL;
89              prev = &req->dl_next) {
90                 const struct inet6_request_sock *treq = inet6_rsk(req);
91
92                 if (inet_rsk(req)->rmt_port == rport &&
93                     req->rsk_ops->family == AF_INET6 &&
94                     ipv6_addr_equal(&treq->rmt_addr, raddr) &&
95                     ipv6_addr_equal(&treq->loc_addr, laddr) &&
96                     (!treq->iif || treq->iif == iif)) {
97                         BUG_TRAP(req->sk == NULL);
98                         *prevp = prev;
99                         return req;
100                 }
101         }
102
103         return NULL;
104 }
105
106 EXPORT_SYMBOL_GPL(inet6_csk_search_req);
107
108 void inet6_csk_reqsk_queue_hash_add(struct sock *sk,
109                                     struct request_sock *req,
110                                     const unsigned long timeout)
111 {
112         struct inet_connection_sock *icsk = inet_csk(sk);
113         struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt;
114         const u32 h = inet6_synq_hash(&inet6_rsk(req)->rmt_addr,
115                                       inet_rsk(req)->rmt_port,
116                                       lopt->hash_rnd, lopt->nr_table_entries);
117
118         reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout);
119         inet_csk_reqsk_queue_added(sk, timeout);
120 }
121
122 EXPORT_SYMBOL_GPL(inet6_csk_reqsk_queue_hash_add);
123
124 void inet6_csk_addr2sockaddr(struct sock *sk, struct sockaddr * uaddr)
125 {
126         struct ipv6_pinfo *np = inet6_sk(sk);
127         struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) uaddr;
128
129         sin6->sin6_family = AF_INET6;
130         ipv6_addr_copy(&sin6->sin6_addr, &np->daddr);
131         sin6->sin6_port = inet_sk(sk)->dport;
132         /* We do not store received flowlabel for TCP */
133         sin6->sin6_flowinfo = 0;
134         sin6->sin6_scope_id = 0;
135         if (sk->sk_bound_dev_if &&
136             ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL)
137                 sin6->sin6_scope_id = sk->sk_bound_dev_if;
138 }
139
140 EXPORT_SYMBOL_GPL(inet6_csk_addr2sockaddr);
141
142 int inet6_csk_xmit(struct sk_buff *skb, int ipfragok)
143 {
144         struct sock *sk = skb->sk;
145         struct inet_sock *inet = inet_sk(sk);
146         struct ipv6_pinfo *np = inet6_sk(sk);
147         struct flowi fl;
148         struct dst_entry *dst;
149         struct in6_addr *final_p = NULL, final;
150
151         memset(&fl, 0, sizeof(fl));
152         fl.proto = sk->sk_protocol;
153         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
154         ipv6_addr_copy(&fl.fl6_src, &np->saddr);
155         fl.fl6_flowlabel = np->flow_label;
156         IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel);
157         fl.oif = sk->sk_bound_dev_if;
158         fl.fl_ip_sport = inet->sport;
159         fl.fl_ip_dport = inet->dport;
160         security_sk_classify_flow(sk, &fl);
161
162         if (np->opt && np->opt->srcrt) {
163                 struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt;
164                 ipv6_addr_copy(&final, &fl.fl6_dst);
165                 ipv6_addr_copy(&fl.fl6_dst, rt0->addr);
166                 final_p = &final;
167         }
168
169         dst = __sk_dst_check(sk, np->dst_cookie);
170
171         if (dst == NULL) {
172                 int err = ip6_dst_lookup(sk, &dst, &fl);
173
174                 if (err) {
175                         sk->sk_err_soft = -err;
176                         kfree_skb(skb);
177                         return err;
178                 }
179
180                 if (final_p)
181                         ipv6_addr_copy(&fl.fl6_dst, final_p);
182
183                 if ((err = xfrm_lookup(&dst, &fl, sk, 0)) < 0) {
184                         sk->sk_route_caps = 0;
185                         kfree_skb(skb);
186                         return err;
187                 }
188
189                 __ip6_dst_store(sk, dst, NULL, NULL);
190         }
191
192         skb->dst = dst_clone(dst);
193
194         /* Restore final destination back after routing done */
195         ipv6_addr_copy(&fl.fl6_dst, &np->daddr);
196
197         return ip6_xmit(sk, skb, &fl, np->opt, 0);
198 }
199
200 EXPORT_SYMBOL_GPL(inet6_csk_xmit);