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 #include <net/sock_reuseport.h> 30 31 struct dst_entry *inet6_csk_route_req(const struct sock *sk, 32 struct flowi6 *fl6, 33 const struct request_sock *req, 34 u8 proto) 35 { 36 struct inet_request_sock *ireq = inet_rsk(req); 37 const struct ipv6_pinfo *np = inet6_sk(sk); 38 struct in6_addr *final_p, final; 39 struct dst_entry *dst; 40 41 memset(fl6, 0, sizeof(*fl6)); 42 fl6->flowi6_proto = proto; 43 fl6->daddr = ireq->ir_v6_rmt_addr; 44 rcu_read_lock(); 45 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); 46 rcu_read_unlock(); 47 fl6->saddr = ireq->ir_v6_loc_addr; 48 fl6->flowi6_oif = ireq->ir_iif; 49 fl6->flowi6_mark = ireq->ir_mark; 50 fl6->fl6_dport = ireq->ir_rmt_port; 51 fl6->fl6_sport = htons(ireq->ir_num); 52 fl6->flowi6_uid = sk->sk_uid; 53 security_req_classify_flow(req, flowi6_to_flowi(fl6)); 54 55 dst = ip6_dst_lookup_flow(sk, fl6, final_p); 56 if (IS_ERR(dst)) 57 return NULL; 58 59 return dst; 60 } 61 EXPORT_SYMBOL(inet6_csk_route_req); 62 63 void inet6_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr) 64 { 65 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) uaddr; 66 67 sin6->sin6_family = AF_INET6; 68 sin6->sin6_addr = sk->sk_v6_daddr; 69 sin6->sin6_port = inet_sk(sk)->inet_dport; 70 /* We do not store received flowlabel for TCP */ 71 sin6->sin6_flowinfo = 0; 72 sin6->sin6_scope_id = ipv6_iface_scope_id(&sin6->sin6_addr, 73 sk->sk_bound_dev_if); 74 } 75 EXPORT_SYMBOL_GPL(inet6_csk_addr2sockaddr); 76 77 static inline 78 struct dst_entry *__inet6_csk_dst_check(struct sock *sk, u32 cookie) 79 { 80 return __sk_dst_check(sk, cookie); 81 } 82 83 static struct dst_entry *inet6_csk_route_socket(struct sock *sk, 84 struct flowi6 *fl6) 85 { 86 struct inet_sock *inet = inet_sk(sk); 87 struct ipv6_pinfo *np = inet6_sk(sk); 88 struct in6_addr *final_p, final; 89 struct dst_entry *dst; 90 91 memset(fl6, 0, sizeof(*fl6)); 92 fl6->flowi6_proto = sk->sk_protocol; 93 fl6->daddr = sk->sk_v6_daddr; 94 fl6->saddr = np->saddr; 95 fl6->flowlabel = np->flow_label; 96 IP6_ECN_flow_xmit(sk, fl6->flowlabel); 97 fl6->flowi6_oif = sk->sk_bound_dev_if; 98 fl6->flowi6_mark = sk->sk_mark; 99 fl6->fl6_sport = inet->inet_sport; 100 fl6->fl6_dport = inet->inet_dport; 101 fl6->flowi6_uid = sk->sk_uid; 102 security_sk_classify_flow(sk, flowi6_to_flowi(fl6)); 103 104 rcu_read_lock(); 105 final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final); 106 rcu_read_unlock(); 107 108 dst = __inet6_csk_dst_check(sk, np->dst_cookie); 109 if (!dst) { 110 dst = ip6_dst_lookup_flow(sk, fl6, final_p); 111 112 if (!IS_ERR(dst)) 113 ip6_dst_store(sk, dst, NULL, NULL); 114 } 115 return dst; 116 } 117 118 int inet6_csk_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl_unused) 119 { 120 struct ipv6_pinfo *np = inet6_sk(sk); 121 struct flowi6 fl6; 122 struct dst_entry *dst; 123 int res; 124 125 dst = inet6_csk_route_socket(sk, &fl6); 126 if (IS_ERR(dst)) { 127 sk->sk_err_soft = -PTR_ERR(dst); 128 sk->sk_route_caps = 0; 129 kfree_skb(skb); 130 return PTR_ERR(dst); 131 } 132 133 rcu_read_lock(); 134 skb_dst_set_noref(skb, dst); 135 136 /* Restore final destination back after routing done */ 137 fl6.daddr = sk->sk_v6_daddr; 138 139 res = ip6_xmit(sk, skb, &fl6, sk->sk_mark, rcu_dereference(np->opt), 140 np->tclass); 141 rcu_read_unlock(); 142 return res; 143 } 144 EXPORT_SYMBOL_GPL(inet6_csk_xmit); 145 146 struct dst_entry *inet6_csk_update_pmtu(struct sock *sk, u32 mtu) 147 { 148 struct flowi6 fl6; 149 struct dst_entry *dst = inet6_csk_route_socket(sk, &fl6); 150 151 if (IS_ERR(dst)) 152 return NULL; 153 dst->ops->update_pmtu(dst, sk, NULL, mtu); 154 155 dst = inet6_csk_route_socket(sk, &fl6); 156 return IS_ERR(dst) ? NULL : dst; 157 } 158 EXPORT_SYMBOL_GPL(inet6_csk_update_pmtu); 159