// 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)) { WRITE_ONCE(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);