projects/linux·blob master · refs

304 lines · 8.1 KiB

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