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 * "Ping" sockets
8 *
9 * Based on ipv4/ping.c code.
10 *
11 * Authors: Lorenzo Colitti (IPv6 support)
12 * Vasiliy Kulikov / Openwall (IPv4 implementation, for Linux 2.6),
13 * Pavel Kankovsky (IPv4 implementation, for Linux 2.4.32)
14 */
15
16#include <net/addrconf.h>
17#include <net/ipv6.h>
18#include <net/ip6_route.h>
19#include <net/protocol.h>
20#include <net/udp.h>
21#include <net/transp_v6.h>
22#include <linux/proc_fs.h>
23#include <linux/bpf-cgroup.h>
24#include <net/ping.h>
25
26/* Compatibility glue so we can support IPv6 when it's compiled as a module */
27static int dummy_ipv6_recv_error(struct sock *sk, struct msghdr *msg, int len,
28 int *addr_len)
29{
30 return -EAFNOSUPPORT;
31}
32static void dummy_ip6_datagram_recv_ctl(struct sock *sk, struct msghdr *msg,
33 struct sk_buff *skb)
34{
35}
36static int dummy_icmpv6_err_convert(u8 type, u8 code, int *err)
37{
38 return -EAFNOSUPPORT;
39}
40static void dummy_ipv6_icmp_error(struct sock *sk, struct sk_buff *skb, int err,
41 __be16 port, u32 info, u8 *payload) {}
42static int dummy_ipv6_chk_addr(struct net *net, const struct in6_addr *addr,
43 const struct net_device *dev, int strict)
44{
45 return 0;
46}
47
48static int ping_v6_pre_connect(struct sock *sk, struct sockaddr *uaddr,
49 int addr_len)
50{
51 /* This check is replicated from __ip6_datagram_connect() and
52 * intended to prevent BPF program called below from accessing
53 * bytes that are out of the bound specified by user in addr_len.
54 */
55
56 if (addr_len < SIN6_LEN_RFC2133)
57 return -EINVAL;
58
59 return BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr, &addr_len);
60}
61
62static int ping_v6_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
63{
64 struct inet_sock *inet = inet_sk(sk);
65 struct ipv6_pinfo *np = inet6_sk(sk: sk);
66 struct icmp6hdr user_icmph;
67 int addr_type;
68 struct in6_addr *daddr;
69 int oif = 0;
70 struct flowi6 fl6;
71 int err;
72 struct dst_entry *dst;
73 struct rt6_info *rt;
74 struct pingfakehdr pfh;
75 struct ipcm6_cookie ipc6;
76
77 err = ping_common_sendmsg(AF_INET6, msg, len, user_icmph: &user_icmph,
78 icmph_len: sizeof(user_icmph));
79 if (err)
80 return err;
81
82 memset(s: &fl6, c: 0, n: sizeof(fl6));
83
84 if (msg->msg_name) {
85 DECLARE_SOCKADDR(struct sockaddr_in6 *, u, msg->msg_name);
86 if (msg->msg_namelen < sizeof(*u))
87 return -EINVAL;
88 if (u->sin6_family != AF_INET6) {
89 return -EAFNOSUPPORT;
90 }
91 daddr = &(u->sin6_addr);
92 if (inet6_test_bit(SNDFLOW, sk))
93 fl6.flowlabel = u->sin6_flowinfo & IPV6_FLOWINFO_MASK;
94 if (__ipv6_addr_needs_scope_id(type: ipv6_addr_type(addr: daddr)))
95 oif = u->sin6_scope_id;
96 } else {
97 if (sk->sk_state != TCP_ESTABLISHED)
98 return -EDESTADDRREQ;
99 daddr = &sk->sk_v6_daddr;
100 fl6.flowlabel = np->flow_label;
101 }
102
103 if (!oif)
104 oif = sk->sk_bound_dev_if;
105
106 if (!oif)
107 oif = np->sticky_pktinfo.ipi6_ifindex;
108
109 if (!oif && ipv6_addr_is_multicast(addr: daddr))
110 oif = READ_ONCE(np->mcast_oif);
111 else if (!oif)
112 oif = READ_ONCE(np->ucast_oif);
113
114 addr_type = ipv6_addr_type(addr: daddr);
115 if ((__ipv6_addr_needs_scope_id(type: addr_type) && !oif) ||
116 (addr_type & IPV6_ADDR_MAPPED) ||
117 (oif && sk->sk_bound_dev_if && oif != sk->sk_bound_dev_if &&
118 l3mdev_master_ifindex_by_index(net: sock_net(sk), ifindex: oif) != sk->sk_bound_dev_if))
119 return -EINVAL;
120
121 ipcm6_init_sk(ipc6: &ipc6, sk);
122
123 fl6.flowi6_oif = oif;
124
125 if (msg->msg_controllen) {
126 struct ipv6_txoptions opt = {};
127
128 opt.tot_len = sizeof(opt);
129 ipc6.opt = &opt;
130
131 err = ip6_datagram_send_ctl(net: sock_net(sk), sk, msg, fl6: &fl6, ipc6: &ipc6);
132 if (err < 0)
133 return err;
134
135 /* Changes to txoptions and flow info are not implemented, yet.
136 * Drop the options.
137 */
138 ipc6.opt = NULL;
139 }
140
141 fl6.flowi6_proto = IPPROTO_ICMPV6;
142 fl6.saddr = np->saddr;
143 fl6.daddr = *daddr;
144 fl6.flowi6_mark = ipc6.sockc.mark;
145 fl6.flowi6_uid = sk_uid(sk);
146 fl6.fl6_icmp_type = user_icmph.icmp6_type;
147 fl6.fl6_icmp_code = user_icmph.icmp6_code;
148 security_sk_classify_flow(sk, flic: flowi6_to_flowi_common(fl6: &fl6));
149
150 fl6.flowlabel = ip6_make_flowinfo(tclass: ipc6.tclass, flowlabel: fl6.flowlabel);
151
152 dst = ip6_sk_dst_lookup_flow(sk, fl6: &fl6, final_dst: daddr, connected: false);
153 if (IS_ERR(ptr: dst))
154 return PTR_ERR(ptr: dst);
155 rt = dst_rt6_info(dst);
156
157 if (!fl6.flowi6_oif && ipv6_addr_is_multicast(addr: &fl6.daddr))
158 fl6.flowi6_oif = READ_ONCE(np->mcast_oif);
159 else if (!fl6.flowi6_oif)
160 fl6.flowi6_oif = READ_ONCE(np->ucast_oif);
161
162 pfh.icmph.type = user_icmph.icmp6_type;
163 pfh.icmph.code = user_icmph.icmp6_code;
164 pfh.icmph.checksum = 0;
165 pfh.icmph.un.echo.id = inet->inet_sport;
166 pfh.icmph.un.echo.sequence = user_icmph.icmp6_sequence;
167 pfh.msg = msg;
168 pfh.wcheck = 0;
169 pfh.family = AF_INET6;
170
171 if (ipc6.hlimit < 0)
172 ipc6.hlimit = ip6_sk_dst_hoplimit(np, fl6: &fl6, dst);
173
174 lock_sock(sk);
175 err = ip6_append_data(sk, getfrag: ping_getfrag, from: &pfh, length: len,
176 transhdrlen: sizeof(struct icmp6hdr), ipc6: &ipc6, fl6: &fl6, rt,
177 MSG_DONTWAIT);
178
179 if (err) {
180 ICMP6_INC_STATS(sock_net(sk), rt->rt6i_idev,
181 ICMP6_MIB_OUTERRORS);
182 ip6_flush_pending_frames(sk);
183 } else {
184 icmpv6_push_pending_frames(sk, fl6: &fl6,
185 thdr: (struct icmp6hdr *)&pfh.icmph, len);
186 }
187 release_sock(sk);
188
189 dst_release(dst);
190
191 if (err)
192 return err;
193
194 return len;
195}
196
197struct proto pingv6_prot = {
198 .name = "PINGv6",
199 .owner = THIS_MODULE,
200 .init = ping_init_sock,
201 .close = ping_close,
202 .pre_connect = ping_v6_pre_connect,
203 .connect = ip6_datagram_connect_v6_only,
204 .disconnect = __udp_disconnect,
205 .setsockopt = ipv6_setsockopt,
206 .getsockopt = ipv6_getsockopt,
207 .sendmsg = ping_v6_sendmsg,
208 .recvmsg = ping_recvmsg,
209 .bind = ping_bind,
210 .backlog_rcv = ping_queue_rcv_skb,
211 .unhash = ping_unhash,
212 .get_port = ping_get_port,
213 .put_port = ping_unhash,
214 .obj_size = sizeof(struct raw6_sock),
215 .ipv6_pinfo_offset = offsetof(struct raw6_sock, inet6),
216};
217EXPORT_SYMBOL_GPL(pingv6_prot);
218
219static struct inet_protosw pingv6_protosw = {
220 .type = SOCK_DGRAM,
221 .protocol = IPPROTO_ICMPV6,
222 .prot = &pingv6_prot,
223 .ops = &inet6_sockraw_ops,
224 .flags = INET_PROTOSW_REUSE,
225};
226
227#ifdef CONFIG_PROC_FS
228static void *ping_v6_seq_start(struct seq_file *seq, loff_t *pos)
229{
230 return ping_seq_start(seq, pos, AF_INET6);
231}
232
233static int ping_v6_seq_show(struct seq_file *seq, void *v)
234{
235 if (v == SEQ_START_TOKEN) {
236 seq_puts(m: seq, IPV6_SEQ_DGRAM_HEADER);
237 } else {
238 int bucket = ((struct ping_iter_state *) seq->private)->bucket;
239 struct inet_sock *inet = inet_sk((struct sock *)v);
240 __u16 srcp = ntohs(inet->inet_sport);
241 __u16 destp = ntohs(inet->inet_dport);
242 ip6_dgram_sock_seq_show(seq, sp: v, srcp, destp, bucket);
243 }
244 return 0;
245}
246
247static const struct seq_operations ping_v6_seq_ops = {
248 .start = ping_v6_seq_start,
249 .show = ping_v6_seq_show,
250 .next = ping_seq_next,
251 .stop = ping_seq_stop,
252};
253
254static int __net_init ping_v6_proc_init_net(struct net *net)
255{
256 if (!proc_create_net("icmp6", 0444, net->proc_net, &ping_v6_seq_ops,
257 sizeof(struct ping_iter_state)))
258 return -ENOMEM;
259 return 0;
260}
261
262static void __net_exit ping_v6_proc_exit_net(struct net *net)
263{
264 remove_proc_entry("icmp6", net->proc_net);
265}
266
267static struct pernet_operations ping_v6_net_ops = {
268 .init = ping_v6_proc_init_net,
269 .exit = ping_v6_proc_exit_net,
270};
271#endif
272
273int __init pingv6_init(void)
274{
275#ifdef CONFIG_PROC_FS
276 int ret = register_pernet_subsys(&ping_v6_net_ops);
277 if (ret)
278 return ret;
279#endif
280 pingv6_ops.ipv6_recv_error = ipv6_recv_error;
281 pingv6_ops.ip6_datagram_recv_common_ctl = ip6_datagram_recv_common_ctl;
282 pingv6_ops.ip6_datagram_recv_specific_ctl =
283 ip6_datagram_recv_specific_ctl;
284 pingv6_ops.icmpv6_err_convert = icmpv6_err_convert;
285 pingv6_ops.ipv6_icmp_error = ipv6_icmp_error;
286 pingv6_ops.ipv6_chk_addr = ipv6_chk_addr;
287 return inet6_register_protosw(p: &pingv6_protosw);
288}
289
290/* This never gets called because it's not possible to unload the ipv6 module,
291 * but just in case.
292 */
293void pingv6_exit(void)
294{
295 pingv6_ops.ipv6_recv_error = dummy_ipv6_recv_error;
296 pingv6_ops.ip6_datagram_recv_common_ctl = dummy_ip6_datagram_recv_ctl;
297 pingv6_ops.ip6_datagram_recv_specific_ctl = dummy_ip6_datagram_recv_ctl;
298 pingv6_ops.icmpv6_err_convert = dummy_icmpv6_err_convert;
299 pingv6_ops.ipv6_icmp_error = dummy_ipv6_icmp_error;
300 pingv6_ops.ipv6_chk_addr = dummy_ipv6_chk_addr;
301#ifdef CONFIG_PROC_FS
302 unregister_pernet_subsys(&ping_v6_net_ops);
303#endif
304 inet6_unregister_protosw(p: &pingv6_protosw);
305}
306