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 /* 37 * See comment in inet_csk_bind_conflict about sock lookup 38 * vs net namespaces issues. 39 */ 40 sk_for_each_bound(sk2, node, &tb->owners) { 41 if (sk != sk2 && 42 (!sk->sk_bound_dev_if || 43 !sk2->sk_bound_dev_if || 44 sk->sk_bound_dev_if == sk2->sk_bound_dev_if) && 45 (!sk->sk_reuse || !sk2->sk_reuse || 46 sk2->sk_state == TCP_LISTEN) && 47 ipv6_rcv_saddr_equal(sk, sk2)) 48 break; 49 } 50 51 return node != NULL; 52 } 53 54 EXPORT_SYMBOL_GPL(inet6_csk_bind_conflict); 55 56 /* 57 * request_sock (formerly open request) hash tables. 58 */ 59 static u32 inet6_synq_hash(const struct in6_addr *raddr, const __be16 rport, 60 const u32 rnd, const u16 synq_hsize) 61 { 62 u32 a = (__force u32)raddr->s6_addr32[0]; 63 u32 b = (__force u32)raddr->s6_addr32[1]; 64 u32 c = (__force u32)raddr->s6_addr32[2]; 65 66 a += JHASH_GOLDEN_RATIO; 67 b += JHASH_GOLDEN_RATIO; 68 c += rnd; 69 __jhash_mix(a, b, c); 70 71 a += (__force u32)raddr->s6_addr32[3]; 72 b += (__force u32)rport; 73 __jhash_mix(a, b, c); 74 75 return c & (synq_hsize - 1); 76 } 77 78 struct request_sock *inet6_csk_search_req(const struct sock *sk, 79 struct request_sock ***prevp, 80 const __be16 rport, 81 const struct in6_addr *raddr, 82 const struct in6_addr *laddr, 83 const int iif) 84 { 85 const struct inet_connection_sock *icsk = inet_csk(sk); 86 struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt; 87 struct request_sock *req, **prev; 88 89 for (prev = &lopt->syn_table[inet6_synq_hash(raddr, rport, 90 lopt->hash_rnd, 91 lopt->nr_table_entries)]; 92 (req = *prev) != NULL; 93 prev = &req->dl_next) { 94 const struct inet6_request_sock *treq = inet6_rsk(req); 95 96 if (inet_rsk(req)->rmt_port == rport && 97 req->rsk_ops->family == AF_INET6 && 98 ipv6_addr_equal(&treq->rmt_addr, raddr) && 99 ipv6_addr_equal(&treq->loc_addr, laddr) && 100 (!treq->iif || treq->iif == iif)) { 101 WARN_ON(req->sk != NULL); 102 *prevp = prev; 103 return req; 104 } 105 } 106 107 return NULL; 108 } 109 110 EXPORT_SYMBOL_GPL(inet6_csk_search_req); 111 112 void inet6_csk_reqsk_queue_hash_add(struct sock *sk, 113 struct request_sock *req, 114 const unsigned long timeout) 115 { 116 struct inet_connection_sock *icsk = inet_csk(sk); 117 struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt; 118 const u32 h = inet6_synq_hash(&inet6_rsk(req)->rmt_addr, 119 inet_rsk(req)->rmt_port, 120 lopt->hash_rnd, lopt->nr_table_entries); 121 122 reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout); 123 inet_csk_reqsk_queue_added(sk, timeout); 124 } 125 126 EXPORT_SYMBOL_GPL(inet6_csk_reqsk_queue_hash_add); 127 128 void inet6_csk_addr2sockaddr(struct sock *sk, struct sockaddr * uaddr) 129 { 130 struct ipv6_pinfo *np = inet6_sk(sk); 131 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) uaddr; 132 133 sin6->sin6_family = AF_INET6; 134 ipv6_addr_copy(&sin6->sin6_addr, &np->daddr); 135 sin6->sin6_port = inet_sk(sk)->dport; 136 /* We do not store received flowlabel for TCP */ 137 sin6->sin6_flowinfo = 0; 138 sin6->sin6_scope_id = 0; 139 if (sk->sk_bound_dev_if && 140 ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) 141 sin6->sin6_scope_id = sk->sk_bound_dev_if; 142 } 143 144 EXPORT_SYMBOL_GPL(inet6_csk_addr2sockaddr); 145 146 static inline 147 void __inet6_csk_dst_store(struct sock *sk, struct dst_entry *dst, 148 struct in6_addr *daddr, struct in6_addr *saddr) 149 { 150 __ip6_dst_store(sk, dst, daddr, saddr); 151 152 #ifdef CONFIG_XFRM 153 { 154 struct rt6_info *rt = (struct rt6_info *)dst; 155 rt->rt6i_flow_cache_genid = atomic_read(&flow_cache_genid); 156 } 157 #endif 158 } 159 160 static inline 161 struct dst_entry *__inet6_csk_dst_check(struct sock *sk, u32 cookie) 162 { 163 struct dst_entry *dst; 164 165 dst = __sk_dst_check(sk, cookie); 166 167 #ifdef CONFIG_XFRM 168 if (dst) { 169 struct rt6_info *rt = (struct rt6_info *)dst; 170 if (rt->rt6i_flow_cache_genid != atomic_read(&flow_cache_genid)) { 171 sk->sk_dst_cache = NULL; 172 dst_release(dst); 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.fl_ip_sport = inet->sport; 198 fl.fl_ip_dport = inet->dport; 199 security_sk_classify_flow(sk, &fl); 200 201 if (np->opt && np->opt->srcrt) { 202 struct rt0_hdr *rt0 = (struct rt0_hdr *)np->opt->srcrt; 203 ipv6_addr_copy(&final, &fl.fl6_dst); 204 ipv6_addr_copy(&fl.fl6_dst, rt0->addr); 205 final_p = &final; 206 } 207 208 dst = __inet6_csk_dst_check(sk, np->dst_cookie); 209 210 if (dst == NULL) { 211 int err = ip6_dst_lookup(sk, &dst, &fl); 212 213 if (err) { 214 sk->sk_err_soft = -err; 215 kfree_skb(skb); 216 return err; 217 } 218 219 if (final_p) 220 ipv6_addr_copy(&fl.fl6_dst, final_p); 221 222 if ((err = xfrm_lookup(sock_net(sk), &dst, &fl, sk, 0)) < 0) { 223 sk->sk_route_caps = 0; 224 kfree_skb(skb); 225 return err; 226 } 227 228 __inet6_csk_dst_store(sk, dst, NULL, NULL); 229 } 230 231 skb_dst_set(skb, dst_clone(dst)); 232 233 /* Restore final destination back after routing done */ 234 ipv6_addr_copy(&fl.fl6_dst, &np->daddr); 235 236 return ip6_xmit(sk, skb, &fl, np->opt, 0); 237 } 238 239 EXPORT_SYMBOL_GPL(inet6_csk_xmit); 240