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 ((1 << sk2->sk_state) & (TCPF_LISTEN | TCPF_CLOSE))) && 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 flowi fl; 65 66 memset(&fl, 0, sizeof(fl)); 67 fl.proto = IPPROTO_TCP; 68 ipv6_addr_copy(&fl.fl6_dst, &treq->rmt_addr); 69 final_p = fl6_update_dst(&fl, np->opt, &final); 70 ipv6_addr_copy(&fl.fl6_src, &treq->loc_addr); 71 fl.oif = sk->sk_bound_dev_if; 72 fl.mark = sk->sk_mark; 73 fl.fl_ip_dport = inet_rsk(req)->rmt_port; 74 fl.fl_ip_sport = inet_rsk(req)->loc_port; 75 security_req_classify_flow(req, &fl); 76 77 if (ip6_dst_lookup(sk, &dst, &fl)) 78 return NULL; 79 80 if (final_p) 81 ipv6_addr_copy(&fl.fl6_dst, final_p); 82 83 if ((xfrm_lookup(sock_net(sk), &dst, &fl, sk, 0)) < 0) 84 return NULL; 85 86 return dst; 87 } 88 89 /* 90 * request_sock (formerly open request) hash tables. 91 */ 92 static u32 inet6_synq_hash(const struct in6_addr *raddr, const __be16 rport, 93 const u32 rnd, const u16 synq_hsize) 94 { 95 u32 c; 96 97 c = jhash_3words((__force u32)raddr->s6_addr32[0], 98 (__force u32)raddr->s6_addr32[1], 99 (__force u32)raddr->s6_addr32[2], 100 rnd); 101 102 c = jhash_2words((__force u32)raddr->s6_addr32[3], 103 (__force u32)rport, 104 c); 105 106 return c & (synq_hsize - 1); 107 } 108 109 struct request_sock *inet6_csk_search_req(const struct sock *sk, 110 struct request_sock ***prevp, 111 const __be16 rport, 112 const struct in6_addr *raddr, 113 const struct in6_addr *laddr, 114 const int iif) 115 { 116 const struct inet_connection_sock *icsk = inet_csk(sk); 117 struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt; 118 struct request_sock *req, **prev; 119 120 for (prev = &lopt->syn_table[inet6_synq_hash(raddr, rport, 121 lopt->hash_rnd, 122 lopt->nr_table_entries)]; 123 (req = *prev) != NULL; 124 prev = &req->dl_next) { 125 const struct inet6_request_sock *treq = inet6_rsk(req); 126 127 if (inet_rsk(req)->rmt_port == rport && 128 req->rsk_ops->family == AF_INET6 && 129 ipv6_addr_equal(&treq->rmt_addr, raddr) && 130 ipv6_addr_equal(&treq->loc_addr, laddr) && 131 (!treq->iif || treq->iif == iif)) { 132 WARN_ON(req->sk != NULL); 133 *prevp = prev; 134 return req; 135 } 136 } 137 138 return NULL; 139 } 140 141 EXPORT_SYMBOL_GPL(inet6_csk_search_req); 142 143 void inet6_csk_reqsk_queue_hash_add(struct sock *sk, 144 struct request_sock *req, 145 const unsigned long timeout) 146 { 147 struct inet_connection_sock *icsk = inet_csk(sk); 148 struct listen_sock *lopt = icsk->icsk_accept_queue.listen_opt; 149 const u32 h = inet6_synq_hash(&inet6_rsk(req)->rmt_addr, 150 inet_rsk(req)->rmt_port, 151 lopt->hash_rnd, lopt->nr_table_entries); 152 153 reqsk_queue_hash_req(&icsk->icsk_accept_queue, h, req, timeout); 154 inet_csk_reqsk_queue_added(sk, timeout); 155 } 156 157 EXPORT_SYMBOL_GPL(inet6_csk_reqsk_queue_hash_add); 158 159 void inet6_csk_addr2sockaddr(struct sock *sk, struct sockaddr * uaddr) 160 { 161 struct ipv6_pinfo *np = inet6_sk(sk); 162 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) uaddr; 163 164 sin6->sin6_family = AF_INET6; 165 ipv6_addr_copy(&sin6->sin6_addr, &np->daddr); 166 sin6->sin6_port = inet_sk(sk)->inet_dport; 167 /* We do not store received flowlabel for TCP */ 168 sin6->sin6_flowinfo = 0; 169 sin6->sin6_scope_id = 0; 170 if (sk->sk_bound_dev_if && 171 ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LINKLOCAL) 172 sin6->sin6_scope_id = sk->sk_bound_dev_if; 173 } 174 175 EXPORT_SYMBOL_GPL(inet6_csk_addr2sockaddr); 176 177 static inline 178 void __inet6_csk_dst_store(struct sock *sk, struct dst_entry *dst, 179 struct in6_addr *daddr, struct in6_addr *saddr) 180 { 181 __ip6_dst_store(sk, dst, daddr, saddr); 182 183 #ifdef CONFIG_XFRM 184 { 185 struct rt6_info *rt = (struct rt6_info *)dst; 186 rt->rt6i_flow_cache_genid = atomic_read(&flow_cache_genid); 187 } 188 #endif 189 } 190 191 static inline 192 struct dst_entry *__inet6_csk_dst_check(struct sock *sk, u32 cookie) 193 { 194 struct dst_entry *dst; 195 196 dst = __sk_dst_check(sk, cookie); 197 198 #ifdef CONFIG_XFRM 199 if (dst) { 200 struct rt6_info *rt = (struct rt6_info *)dst; 201 if (rt->rt6i_flow_cache_genid != atomic_read(&flow_cache_genid)) { 202 __sk_dst_reset(sk); 203 dst = NULL; 204 } 205 } 206 #endif 207 208 return dst; 209 } 210 211 int inet6_csk_xmit(struct sk_buff *skb) 212 { 213 struct sock *sk = skb->sk; 214 struct inet_sock *inet = inet_sk(sk); 215 struct ipv6_pinfo *np = inet6_sk(sk); 216 struct flowi fl; 217 struct dst_entry *dst; 218 struct in6_addr *final_p, final; 219 220 memset(&fl, 0, sizeof(fl)); 221 fl.proto = sk->sk_protocol; 222 ipv6_addr_copy(&fl.fl6_dst, &np->daddr); 223 ipv6_addr_copy(&fl.fl6_src, &np->saddr); 224 fl.fl6_flowlabel = np->flow_label; 225 IP6_ECN_flow_xmit(sk, fl.fl6_flowlabel); 226 fl.oif = sk->sk_bound_dev_if; 227 fl.mark = sk->sk_mark; 228 fl.fl_ip_sport = inet->inet_sport; 229 fl.fl_ip_dport = inet->inet_dport; 230 security_sk_classify_flow(sk, &fl); 231 232 final_p = fl6_update_dst(&fl, np->opt, &final); 233 234 dst = __inet6_csk_dst_check(sk, np->dst_cookie); 235 236 if (dst == NULL) { 237 int err = ip6_dst_lookup(sk, &dst, &fl); 238 239 if (err) { 240 sk->sk_err_soft = -err; 241 kfree_skb(skb); 242 return err; 243 } 244 245 if (final_p) 246 ipv6_addr_copy(&fl.fl6_dst, final_p); 247 248 if ((err = xfrm_lookup(sock_net(sk), &dst, &fl, sk, 0)) < 0) { 249 sk->sk_route_caps = 0; 250 kfree_skb(skb); 251 return err; 252 } 253 254 __inet6_csk_dst_store(sk, dst, NULL, NULL); 255 } 256 257 skb_dst_set(skb, dst_clone(dst)); 258 259 /* Restore final destination back after routing done */ 260 ipv6_addr_copy(&fl.fl6_dst, &np->daddr); 261 262 return ip6_xmit(sk, skb, &fl, np->opt); 263 } 264 265 EXPORT_SYMBOL_GPL(inet6_csk_xmit); 266