1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * INET An implementation of the TCP/IP protocol suite for the LINUX |
4 | * operating system. INET is implemented using the BSD Socket |
5 | * interface as the means of communication with the user level. |
6 | * |
7 | * Support for INET6 connection oriented protocols. |
8 | * |
9 | * Authors: See the TCPv6 sources |
10 | */ |
11 | |
12 | #include <linux/module.h> |
13 | #include <linux/in6.h> |
14 | #include <linux/ipv6.h> |
15 | #include <linux/jhash.h> |
16 | #include <linux/slab.h> |
17 | |
18 | #include <net/addrconf.h> |
19 | #include <net/inet_connection_sock.h> |
20 | #include <net/inet_ecn.h> |
21 | #include <net/inet_hashtables.h> |
22 | #include <net/ip6_route.h> |
23 | #include <net/sock.h> |
24 | #include <net/inet6_connection_sock.h> |
25 | #include <net/sock_reuseport.h> |
26 | |
27 | struct dst_entry *inet6_csk_route_req(const struct sock *sk, |
28 | struct flowi6 *fl6, |
29 | const struct request_sock *req, |
30 | u8 proto) |
31 | { |
32 | struct inet_request_sock *ireq = inet_rsk(sk: req); |
33 | const struct ipv6_pinfo *np = inet6_sk(sk: sk); |
34 | struct in6_addr *final_p, final; |
35 | struct dst_entry *dst; |
36 | |
37 | memset(fl6, 0, sizeof(*fl6)); |
38 | fl6->flowi6_proto = proto; |
39 | fl6->daddr = ireq->ir_v6_rmt_addr; |
40 | rcu_read_lock(); |
41 | final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), orig: &final); |
42 | rcu_read_unlock(); |
43 | fl6->saddr = ireq->ir_v6_loc_addr; |
44 | fl6->flowi6_oif = ireq->ir_iif; |
45 | fl6->flowi6_mark = ireq->ir_mark; |
46 | fl6->fl6_dport = ireq->ir_rmt_port; |
47 | fl6->fl6_sport = htons(ireq->ir_num); |
48 | fl6->flowi6_uid = sk->sk_uid; |
49 | security_req_classify_flow(req, flic: flowi6_to_flowi_common(fl6)); |
50 | |
51 | dst = ip6_dst_lookup_flow(net: sock_net(sk), sk, fl6, final_dst: final_p); |
52 | if (IS_ERR(ptr: dst)) |
53 | return NULL; |
54 | |
55 | return dst; |
56 | } |
57 | EXPORT_SYMBOL(inet6_csk_route_req); |
58 | |
59 | void inet6_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr) |
60 | { |
61 | struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *) uaddr; |
62 | |
63 | sin6->sin6_family = AF_INET6; |
64 | sin6->sin6_addr = sk->sk_v6_daddr; |
65 | sin6->sin6_port = inet_sk(sk)->inet_dport; |
66 | /* We do not store received flowlabel for TCP */ |
67 | sin6->sin6_flowinfo = 0; |
68 | sin6->sin6_scope_id = ipv6_iface_scope_id(addr: &sin6->sin6_addr, |
69 | iface: sk->sk_bound_dev_if); |
70 | } |
71 | EXPORT_SYMBOL_GPL(inet6_csk_addr2sockaddr); |
72 | |
73 | static inline |
74 | struct dst_entry *__inet6_csk_dst_check(struct sock *sk, u32 cookie) |
75 | { |
76 | return __sk_dst_check(sk, cookie); |
77 | } |
78 | |
79 | static struct dst_entry *inet6_csk_route_socket(struct sock *sk, |
80 | struct flowi6 *fl6) |
81 | { |
82 | struct inet_sock *inet = inet_sk(sk); |
83 | struct ipv6_pinfo *np = inet6_sk(sk: sk); |
84 | struct in6_addr *final_p, final; |
85 | struct dst_entry *dst; |
86 | |
87 | memset(fl6, 0, sizeof(*fl6)); |
88 | fl6->flowi6_proto = sk->sk_protocol; |
89 | fl6->daddr = sk->sk_v6_daddr; |
90 | fl6->saddr = np->saddr; |
91 | fl6->flowlabel = np->flow_label; |
92 | IP6_ECN_flow_xmit(sk, fl6->flowlabel); |
93 | fl6->flowi6_oif = sk->sk_bound_dev_if; |
94 | fl6->flowi6_mark = sk->sk_mark; |
95 | fl6->fl6_sport = inet->inet_sport; |
96 | fl6->fl6_dport = inet->inet_dport; |
97 | fl6->flowi6_uid = sk->sk_uid; |
98 | security_sk_classify_flow(sk, flic: flowi6_to_flowi_common(fl6)); |
99 | |
100 | rcu_read_lock(); |
101 | final_p = fl6_update_dst(fl6, rcu_dereference(np->opt), orig: &final); |
102 | rcu_read_unlock(); |
103 | |
104 | dst = __inet6_csk_dst_check(sk, cookie: np->dst_cookie); |
105 | if (!dst) { |
106 | dst = ip6_dst_lookup_flow(net: sock_net(sk), sk, fl6, final_dst: final_p); |
107 | |
108 | if (!IS_ERR(ptr: dst)) |
109 | ip6_dst_store(sk, dst, NULL, NULL); |
110 | } |
111 | return dst; |
112 | } |
113 | |
114 | int inet6_csk_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl_unused) |
115 | { |
116 | struct ipv6_pinfo *np = inet6_sk(sk: sk); |
117 | struct flowi6 fl6; |
118 | struct dst_entry *dst; |
119 | int res; |
120 | |
121 | dst = inet6_csk_route_socket(sk, fl6: &fl6); |
122 | if (IS_ERR(ptr: dst)) { |
123 | WRITE_ONCE(sk->sk_err_soft, -PTR_ERR(dst)); |
124 | sk->sk_route_caps = 0; |
125 | kfree_skb(skb); |
126 | return PTR_ERR(ptr: dst); |
127 | } |
128 | |
129 | rcu_read_lock(); |
130 | skb_dst_set_noref(skb, dst); |
131 | |
132 | /* Restore final destination back after routing done */ |
133 | fl6.daddr = sk->sk_v6_daddr; |
134 | |
135 | res = ip6_xmit(sk, skb, fl6: &fl6, mark: sk->sk_mark, rcu_dereference(np->opt), |
136 | tclass: np->tclass, READ_ONCE(sk->sk_priority)); |
137 | rcu_read_unlock(); |
138 | return res; |
139 | } |
140 | EXPORT_SYMBOL_GPL(inet6_csk_xmit); |
141 | |
142 | struct dst_entry *inet6_csk_update_pmtu(struct sock *sk, u32 mtu) |
143 | { |
144 | struct flowi6 fl6; |
145 | struct dst_entry *dst = inet6_csk_route_socket(sk, fl6: &fl6); |
146 | |
147 | if (IS_ERR(ptr: dst)) |
148 | return NULL; |
149 | dst->ops->update_pmtu(dst, sk, NULL, mtu, true); |
150 | |
151 | dst = inet6_csk_route_socket(sk, fl6: &fl6); |
152 | return IS_ERR(ptr: dst) ? NULL : dst; |
153 | } |
154 | EXPORT_SYMBOL_GPL(inet6_csk_update_pmtu); |
155 | |