inet6_connection_sock.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* INET An implementation of the TCP/IP protocol suite for the LINUX
* operating system. INET is implemented using the BSD Socket
* interface as the means of communication with the user level.
*
* Support for INET6 connection oriented protocols.
*
* Authors: See the TCPv6 sources
*/
#include <linux/module.h>
#include <linux/in6.h>
#include <linux/ipv6.h>
#include <linux/jhash.h>
#include <linux/slab.h>
#include <net/addrconf.h>
#include <net/inet_connection_sock.h>
#include <net/inet_ecn.h>
#include <net/inet_hashtables.h>
#include <net/ip6_route.h>
#include <net/sock.h>
#include <net/inet6_connection_sock.h>
#include <net/sock_reuseport.h>
struct dst_entry *inet6_csk_route_req(const struct sock *sk,
struct flowi6 *fl6,
const struct request_sock *req,
u8 proto)
{
struct inet_request_sock *ireq = inet_rsk(req);
const struct ipv6_pinfo *np = inet6_sk(sk);
struct in6_addr *final_p, final;
struct dst_entry *dst;
memset(fl6, 0, sizeof(*fl6));
fl6->flowi6_proto = proto;
fl6->daddr = ireq->ir_v6_rmt_addr;
rcu_read_lock();
final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
rcu_read_unlock();
fl6->saddr = ireq->ir_v6_loc_addr;
fl6->flowi6_oif = ireq->ir_iif;
fl6->flowi6_mark = ireq->ir_mark;
fl6->fl6_dport = ireq->ir_rmt_port;
fl6->fl6_sport = htons(ireq->ir_num);
fl6->flowi6_uid = sk->sk_uid;
security_req_classify_flow(req, flowi6_to_flowi_common(fl6));
dst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
if (IS_ERR(dst))
return NULL;
return dst;
}
EXPORT_SYMBOL(inet6_csk_route_req);
void inet6_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr)
{
struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) uaddr;
sin6->sin6_family = AF_INET6;
sin6->sin6_addr = sk->sk_v6_daddr;
sin6->sin6_port = inet_sk(sk)->inet_dport;
/* We do not store received flowlabel for TCP */
sin6->sin6_flowinfo = 0;
sin6->sin6_scope_id = ipv6_iface_scope_id(&sin6->sin6_addr,
sk->sk_bound_dev_if);
}
EXPORT_SYMBOL_GPL(inet6_csk_addr2sockaddr);
static inline
struct dst_entry *__inet6_csk_dst_check(struct sock *sk, u32 cookie)
{
return __sk_dst_check(sk, cookie);
}
static struct dst_entry *inet6_csk_route_socket(struct sock *sk,
struct flowi6 *fl6)
{
struct inet_sock *inet = inet_sk(sk);
struct ipv6_pinfo *np = inet6_sk(sk);
struct in6_addr *final_p, final;
struct dst_entry *dst;
memset(fl6, 0, sizeof(*fl6));
fl6->flowi6_proto = sk->sk_protocol;
fl6->daddr = sk->sk_v6_daddr;
fl6->saddr = np->saddr;
fl6->flowlabel = np->flow_label;
IP6_ECN_flow_xmit(sk, fl6->flowlabel);
fl6->flowi6_oif = sk->sk_bound_dev_if;
fl6->flowi6_mark = sk->sk_mark;
fl6->fl6_sport = inet->inet_sport;
fl6->fl6_dport = inet->inet_dport;
fl6->flowi6_uid = sk->sk_uid;
security_sk_classify_flow(sk, flowi6_to_flowi_common(fl6));
rcu_read_lock();
final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), &final);
rcu_read_unlock();
dst = __inet6_csk_dst_check(sk, np->dst_cookie);
if (!dst) {
dst = ip6_dst_lookup_flow(sock_net(sk), sk, fl6, final_p);
if (!IS_ERR(dst))
ip6_dst_store(sk, dst, NULL, NULL);
}
return dst;
}
int inet6_csk_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl_unused)
{
struct ipv6_pinfo *np = inet6_sk(sk);
struct flowi6 fl6;
struct dst_entry *dst;
int res;
dst = inet6_csk_route_socket(sk, &fl6);
if (IS_ERR(dst)) {
sk->sk_err_soft = -PTR_ERR(dst);
sk->sk_route_caps = 0;
kfree_skb(skb);
return PTR_ERR(dst);
}
rcu_read_lock();
skb_dst_set_noref(skb, dst);
/* Restore final destination back after routing done */
fl6.daddr = sk->sk_v6_daddr;
res = ip6_xmit(sk, skb, &fl6, sk->sk_mark, rcu_dereference(np->opt),
np->tclass, sk->sk_priority);
rcu_read_unlock();
return res;
}
EXPORT_SYMBOL_GPL(inet6_csk_xmit);
struct dst_entry *inet6_csk_update_pmtu(struct sock *sk, u32 mtu)
{
struct flowi6 fl6;
struct dst_entry *dst = inet6_csk_route_socket(sk, &fl6);
if (IS_ERR(dst))
return NULL;
dst->ops->update_pmtu(dst, sk, NULL, mtu, true);
dst = inet6_csk_route_socket(sk, &fl6);
return IS_ERR(dst) ? NULL : dst;
}
EXPORT_SYMBOL_GPL(inet6_csk_update_pmtu);