LXR linux/net/ipv6/inet6_connection

   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
  31struct 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(sock_net(sk), sk, fl6, final_p);
  56        if (IS_ERR(dst))
  57                return NULL;
  58
  59        return dst;
  60}
  61EXPORT_SYMBOL(inet6_csk_route_req);
  62
  63void 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}
  75EXPORT_SYMBOL_GPL(inet6_csk_addr2sockaddr);
  76
  77static inline
  78struct dst_entry *__inet6_csk_dst_check(struct sock *sk, u32 cookie)
  79{
  80        return __sk_dst_check(sk, cookie);
  81}
  82
  83static 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(sock_net(sk), sk, fl6, final_p);
 111
 112                if (!IS_ERR(dst))
 113                        ip6_dst_store(sk, dst, NULL, NULL);
 114        }
 115        return dst;
 116}
 117
 118int 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}
 144EXPORT_SYMBOL_GPL(inet6_csk_xmit);
 145
 146struct 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, true);
 154
 155        dst = inet6_csk_route_socket(sk, &fl6);
 156        return IS_ERR(dst) ? NULL : dst;
 157}
 158EXPORT_SYMBOL_GPL(inet6_csk_update_pmtu);
 159