1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * udp_diag.c Module for monitoring UDP transport protocols sockets.
4 *
5 * Authors: Pavel Emelyanov, <xemul@parallels.com>
6 */
7
8
9 #include <linux/module.h>
10 #include <linux/inet_diag.h>
11 #include <linux/udp.h>
12 #include <net/udp.h>
13 #include <net/udplite.h>
14 #include <linux/sock_diag.h>
15
16 static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
17 struct netlink_callback *cb,
18 const struct inet_diag_req_v2 *req,
19 struct nlattr *bc, bool net_admin)
20 {
21 if (!inet_diag_bc_sk(bc, sk))
22 return 0;
23
24 return inet_sk_diag_fill(sk, NULL, skb, req,
25 sk_user_ns(NETLINK_CB(cb->skb).sk),
26 NETLINK_CB(cb->skb).portid,
27 cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh, net_admin);
28 }
29
30 static int udp_dump_one(struct udp_table *tbl, struct sk_buff *in_skb,
31 const struct nlmsghdr *nlh,
32 const struct inet_diag_req_v2 *req)
33 {
34 int err = -EINVAL;
35 struct sock *sk = NULL;
36 struct sk_buff *rep;
37 struct net *net = sock_net(in_skb->sk);
38
39 rcu_read_lock();
40 if (req->sdiag_family == AF_INET)
41 /* src and dst are swapped for historical reasons */
42 sk = __udp4_lib_lookup(net,
43 req->id.idiag_src[0], req->id.idiag_sport,
44 req->id.idiag_dst[0], req->id.idiag_dport,
45 req->id.idiag_if, 0, tbl, NULL);
46 #if IS_ENABLED(CONFIG_IPV6)
47 else if (req->sdiag_family == AF_INET6)
48 sk = __udp6_lib_lookup(net,
49 (struct in6_addr *)req->id.idiag_src,
50 req->id.idiag_sport,
51 (struct in6_addr *)req->id.idiag_dst,
52 req->id.idiag_dport,
53 req->id.idiag_if, 0, tbl, NULL);
54 #endif
55 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
56 sk = NULL;
57 rcu_read_unlock();
58 err = -ENOENT;
59 if (!sk)
60 goto out_nosk;
61
62 err = sock_diag_check_cookie(sk, req->id.idiag_cookie);
63 if (err)
64 goto out;
65
66 err = -ENOMEM;
67 rep = nlmsg_new(nla_total_size(sizeof(struct inet_diag_msg)) +
68 inet_diag_msg_attrs_size() +
69 nla_total_size(sizeof(struct inet_diag_meminfo)) + 64,
70 GFP_KERNEL);
71 if (!rep)
72 goto out;
73
74 err = inet_sk_diag_fill(sk, NULL, rep, req,
75 sk_user_ns(NETLINK_CB(in_skb).sk),
76 NETLINK_CB(in_skb).portid,
77 nlh->nlmsg_seq, 0, nlh,
78 netlink_net_capable(in_skb, CAP_NET_ADMIN));
79 if (err < 0) {
80 WARN_ON(err == -EMSGSIZE);
81 kfree_skb(rep);
82 goto out;
83 }
84 err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid,
85 MSG_DONTWAIT);
86 if (err > 0)
87 err = 0;
88 out:
89 if (sk)
90 sock_put(sk);
91 out_nosk:
92 return err;
93 }
94
95 static void udp_dump(struct udp_table *table, struct sk_buff *skb,
96 struct netlink_callback *cb,
97 const struct inet_diag_req_v2 *r, struct nlattr *bc)
98 {
99 bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
100 struct net *net = sock_net(skb->sk);
101 int num, s_num, slot, s_slot;
102
103 s_slot = cb->args[0];
104 num = s_num = cb->args[1];
105
106 for (slot = s_slot; slot <= table->mask; s_num = 0, slot++) {
107 struct udp_hslot *hslot = &table->hash[slot];
108 struct sock *sk;
109
110 num = 0;
111
112 if (hlist_empty(&hslot->head))
113 continue;
114
115 spin_lock_bh(&hslot->lock);
116 sk_for_each(sk, &hslot->head) {
117 struct inet_sock *inet = inet_sk(sk);
118
119 if (!net_eq(sock_net(sk), net))
120 continue;
121 if (num < s_num)
122 goto next;
123 if (!(r->idiag_states & (1 << sk->sk_state)))
124 goto next;
125 if (r->sdiag_family != AF_UNSPEC &&
126 sk->sk_family != r->sdiag_family)
127 goto next;
128 if (r->id.idiag_sport != inet->inet_sport &&
129 r->id.idiag_sport)
130 goto next;
131 if (r->id.idiag_dport != inet->inet_dport &&
132 r->id.idiag_dport)
133 goto next;
134
135 if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) {
136 spin_unlock_bh(&hslot->lock);
137 goto done;
138 }
139 next:
140 num++;
141 }
142 spin_unlock_bh(&hslot->lock);
143 }
144 done:
145 cb->args[0] = slot;
146 cb->args[1] = num;
147 }
148
149 static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
150 const struct inet_diag_req_v2 *r, struct nlattr *bc)
151 {
152 udp_dump(&udp_table, skb, cb, r, bc);
153 }
154
155 static int udp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
156 const struct inet_diag_req_v2 *req)
157 {
158 return udp_dump_one(&udp_table, in_skb, nlh, req);
159 }
160
161 static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
162 void *info)
163 {
164 r->idiag_rqueue = udp_rqueue_get(sk);
165 r->idiag_wqueue = sk_wmem_alloc_get(sk);
166 }
167
168 #ifdef CONFIG_INET_DIAG_DESTROY
169 static int __udp_diag_destroy(struct sk_buff *in_skb,
170 const struct inet_diag_req_v2 *req,
171 struct udp_table *tbl)
172 {
173 struct net *net = sock_net(in_skb->sk);
174 struct sock *sk;
175 int err;
176
177 rcu_read_lock();
178
179 if (req->sdiag_family == AF_INET)
180 sk = __udp4_lib_lookup(net,
181 req->id.idiag_dst[0], req->id.idiag_dport,
182 req->id.idiag_src[0], req->id.idiag_sport,
183 req->id.idiag_if, 0, tbl, NULL);
184 #if IS_ENABLED(CONFIG_IPV6)
185 else if (req->sdiag_family == AF_INET6) {
186 if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) &&
187 ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src))
188 sk = __udp4_lib_lookup(net,
189 req->id.idiag_dst[3], req->id.idiag_dport,
190 req->id.idiag_src[3], req->id.idiag_sport,
191 req->id.idiag_if, 0, tbl, NULL);
192
193 else
194 sk = __udp6_lib_lookup(net,
195 (struct in6_addr *)req->id.idiag_dst,
196 req->id.idiag_dport,
197 (struct in6_addr *)req->id.idiag_src,
198 req->id.idiag_sport,
199 req->id.idiag_if, 0, tbl, NULL);
200 }
201 #endif
202 else {
203 rcu_read_unlock();
204 return -EINVAL;
205 }
206
207 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
208 sk = NULL;
209
210 rcu_read_unlock();
211
212 if (!sk)
213 return -ENOENT;
214
215 if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) {
216 sock_put(sk);
217 return -ENOENT;
218 }
219
220 err = sock_diag_destroy(sk, ECONNABORTED);
221
222 sock_put(sk);
223
224 return err;
225 }
226
227 static int udp_diag_destroy(struct sk_buff *in_skb,
228 const struct inet_diag_req_v2 *req)
229 {
230 return __udp_diag_destroy(in_skb, req, &udp_table);
231 }
232
233 static int udplite_diag_destroy(struct sk_buff *in_skb,
234 const struct inet_diag_req_v2 *req)
235 {
236 return __udp_diag_destroy(in_skb, req, &udplite_table);
237 }
238
239 #endif
240
241 static const struct inet_diag_handler udp_diag_handler = {
242 .dump = udp_diag_dump,
243 .dump_one = udp_diag_dump_one,
244 .idiag_get_info = udp_diag_get_info,
245 .idiag_type = IPPROTO_UDP,
246 .idiag_info_size = 0,
247 #ifdef CONFIG_INET_DIAG_DESTROY
248 .destroy = udp_diag_destroy,
249 #endif
250 };
251
252 static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
253 const struct inet_diag_req_v2 *r,
254 struct nlattr *bc)
255 {
256 udp_dump(&udplite_table, skb, cb, r, bc);
257 }
258
259 static int udplite_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
260 const struct inet_diag_req_v2 *req)
261 {
262 return udp_dump_one(&udplite_table, in_skb, nlh, req);
263 }
264
265 static const struct inet_diag_handler udplite_diag_handler = {
266 .dump = udplite_diag_dump,
267 .dump_one = udplite_diag_dump_one,
268 .idiag_get_info = udp_diag_get_info,
269 .idiag_type = IPPROTO_UDPLITE,
270 .idiag_info_size = 0,
271 #ifdef CONFIG_INET_DIAG_DESTROY
272 .destroy = udplite_diag_destroy,
273 #endif
274 };
275
276 static int __init udp_diag_init(void)
277 {
278 int err;
279
280 err = inet_diag_register(&udp_diag_handler);
281 if (err)
282 goto out;
283 err = inet_diag_register(&udplite_diag_handler);
284 if (err)
285 goto out_lite;
286 out:
287 return err;
288 out_lite:
289 inet_diag_unregister(&udp_diag_handler);
290 goto out;
291 }
292
293 static void __exit udp_diag_exit(void)
294 {
295 inet_diag_unregister(&udplite_diag_handler);
296 inet_diag_unregister(&udp_diag_handler);
297 }
298
299 module_init(udp_diag_init);
300 module_exit(udp_diag_exit);
301 MODULE_LICENSE("GPL");
302 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */);
303 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */);
304
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