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, bool relax) 32 { 33 const struct sock *sk2; 34 int reuse = sk->sk_reuse; 35 int reuseport = sk->sk_reuseport; 36 kuid_t uid = sock_i_uid((struct sock *)sk); 37 38 /* We must walk the whole port owner list in this case. -DaveM */ 39 /* 40 * See comment in inet_csk_bind_conflict about sock lookup 41 * vs net namespaces issues. 42 */ 43 sk_for_each_bound(sk2, &tb->owners) { 44 if (sk != sk2 && 45 (!sk->sk_bound_dev_if || 46 !sk2->sk_bound_dev_if || 47 sk->sk_bound_dev_if == sk2->sk_bound_dev_if)) { 48 if ((!reuse || !sk2->sk_reuse || 49 sk2->sk_state == TCP_LISTEN) && 50 (!reuseport || !sk2->sk_reuseport || 51 (sk2->sk_state != TCP_TIME_WAIT && 52 !uid_eq(uid, 53 sock_i_uid((struct sock *)sk2))))) { 54 if (ipv6_rcv_saddr_equal(sk, sk2)) 55 break; 56 } 57 if (!relax && reuse && sk2->sk_reuse && 58 sk2->sk_state != TCP_LISTEN && 59 ipv6_rcv_saddr_equal(sk, sk2)) 60 break; 61 } 62 } 63 64 return sk2 != NULL; 65 } 66 EXPORT_SYMBOL_GPL(inet6_csk_bind_conflict); 67 68 struct dst_entry *inet6_csk_route_req(const struct sock *sk, 69 struct flowi6 *fl6, 70 const struct request_sock *req, 71 u8 proto) 72 { 73 struct inet_request_sock *ireq = inet_rsk(req); 74 const struct ipv6_pinfo *np = inet6_sk(sk); 75 struct in6_addr *final_p, final; 76 struct dst_entry *dst; 77 78 memset(fl6, 0, sizeof(*fl6)); 79 fl6->flowi6_proto = proto; 80 fl6->daddr = ireq->ir_v6_rmt_addr; 81 rcu_read_lock(); 82 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); 83 rcu_read_unlock(); 84 fl6->saddr = ireq->ir_v6_loc_addr; 85 fl6->flowi6_oif = ireq->ir_iif; 86 fl6->flowi6_mark = ireq->ir_mark; 87 fl6->fl6_dport = ireq->ir_rmt_port; 88 fl6->fl6_sport = htons(ireq->ir_num); 89 security_req_classify_flow(req, flowi6_to_flowi(fl6)); 90 91 dst = ip6_dst_lookup_flow(sk, fl6, final_p); 92 if (IS_ERR(dst)) 93 return NULL; 94 95 return dst; 96 } 97 EXPORT_SYMBOL(inet6_csk_route_req); 98 99 void inet6_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr) 100 { 101 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) uaddr; 102 103 sin6->sin6_family = AF_INET6; 104 sin6->sin6_addr = sk->sk_v6_daddr; 105 sin6->sin6_port = inet_sk(sk)->inet_dport; 106 /* We do not store received flowlabel for TCP */ 107 sin6->sin6_flowinfo = 0; 108 sin6->sin6_scope_id = ipv6_iface_scope_id(&sin6->sin6_addr, 109 sk->sk_bound_dev_if); 110 } 111 EXPORT_SYMBOL_GPL(inet6_csk_addr2sockaddr); 112 113 static inline 114 struct dst_entry *__inet6_csk_dst_check(struct sock *sk, u32 cookie) 115 { 116 return __sk_dst_check(sk, cookie); 117 } 118 119 static struct dst_entry *inet6_csk_route_socket(struct sock *sk, 120 struct flowi6 *fl6) 121 { 122 struct inet_sock *inet = inet_sk(sk); 123 struct ipv6_pinfo *np = inet6_sk(sk); 124 struct in6_addr *final_p, final; 125 struct dst_entry *dst; 126 127 memset(fl6, 0, sizeof(*fl6)); 128 fl6->flowi6_proto = sk->sk_protocol; 129 fl6->daddr = sk->sk_v6_daddr; 130 fl6->saddr = np->saddr; 131 fl6->flowlabel = np->flow_label; 132 IP6_ECN_flow_xmit(sk, fl6->flowlabel); 133 fl6->flowi6_oif = sk->sk_bound_dev_if; 134 fl6->flowi6_mark = sk->sk_mark; 135 fl6->fl6_sport = inet->inet_sport; 136 fl6->fl6_dport = inet->inet_dport; 137 security_sk_classify_flow(sk, flowi6_to_flowi(fl6)); 138 139 rcu_read_lock(); 140 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); 141 rcu_read_unlock(); 142 143 dst = __inet6_csk_dst_check(sk, np->dst_cookie); 144 if (!dst) { 145 dst = ip6_dst_lookup_flow(sk, fl6, final_p); 146 147 if (!IS_ERR(dst)) 148 ip6_dst_store(sk, dst, NULL, NULL); 149 } 150 return dst; 151 } 152 153 int inet6_csk_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl_unused) 154 { 155 struct ipv6_pinfo *np = inet6_sk(sk); 156 struct flowi6 fl6; 157 struct dst_entry *dst; 158 int res; 159 160 dst = inet6_csk_route_socket(sk, &fl6); 161 if (IS_ERR(dst)) { 162 sk->sk_err_soft = -PTR_ERR(dst); 163 sk->sk_route_caps = 0; 164 kfree_skb(skb); 165 return PTR_ERR(dst); 166 } 167 168 rcu_read_lock(); 169 skb_dst_set_noref(skb, dst); 170 171 /* Restore final destination back after routing done */ 172 fl6.daddr = sk->sk_v6_daddr; 173 174 res = ip6_xmit(sk, skb, &fl6, rcu_dereference(np->opt), 175 np->tclass); 176 rcu_read_unlock(); 177 return res; 178 } 179 EXPORT_SYMBOL_GPL(inet6_csk_xmit); 180 181 struct dst_entry *inet6_csk_update_pmtu(struct sock *sk, u32 mtu) 182 { 183 struct flowi6 fl6; 184 struct dst_entry *dst = inet6_csk_route_socket(sk, &fl6); 185 186 if (IS_ERR(dst)) 187 return NULL; 188 dst->ops->update_pmtu(dst, sk, NULL, mtu); 189 190 dst = inet6_csk_route_socket(sk, &fl6); 191 return IS_ERR(dst) ? NULL : dst; 192 } 193 EXPORT_SYMBOL_GPL(inet6_csk_update_pmtu); 194