1 /*
2 * udp_diag.c Module for monitoring UDP transport protocols sockets.
3 *
4 * Authors: Pavel Emelyanov, <xemul@parallels.com>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12
13 #include <linux/module.h>
14 #include <linux/inet_diag.h>
15 #include <linux/udp.h>
16 #include <net/udp.h>
17 #include <net/udplite.h>
18 #include <linux/sock_diag.h>
19
20 static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
21 struct netlink_callback *cb,
22 const struct inet_diag_req_v2 *req,
23 struct nlattr *bc, bool net_admin)
24 {
25 if (!inet_diag_bc_sk(bc, sk))
26 return 0;
27
28 return inet_sk_diag_fill(sk, NULL, skb, req,
29 sk_user_ns(NETLINK_CB(cb->skb).sk),
30 NETLINK_CB(cb->skb).portid,
31 cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh, net_admin);
32 }
33
34 static int udp_dump_one(struct udp_table *tbl, struct sk_buff *in_skb,
35 const struct nlmsghdr *nlh,
36 const struct inet_diag_req_v2 *req)
37 {
38 int err = -EINVAL;
39 struct sock *sk = NULL;
40 struct sk_buff *rep;
41 struct net *net = sock_net(in_skb->sk);
42
43 rcu_read_lock();
44 if (req->sdiag_family == AF_INET)
45 /* src and dst are swapped for historical reasons */
46 sk = __udp4_lib_lookup(net,
47 req->id.idiag_src[0], req->id.idiag_sport,
48 req->id.idiag_dst[0], req->id.idiag_dport,
49 req->id.idiag_if, 0, tbl, NULL);
50 #if IS_ENABLED(CONFIG_IPV6)
51 else if (req->sdiag_family == AF_INET6)
52 sk = __udp6_lib_lookup(net,
53 (struct in6_addr *)req->id.idiag_src,
54 req->id.idiag_sport,
55 (struct in6_addr *)req->id.idiag_dst,
56 req->id.idiag_dport,
57 req->id.idiag_if, 0, tbl, NULL);
58 #endif
59 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
60 sk = NULL;
61 rcu_read_unlock();
62 err = -ENOENT;
63 if (!sk)
64 goto out_nosk;
65
66 err = sock_diag_check_cookie(sk, req->id.idiag_cookie);
67 if (err)
68 goto out;
69
70 err = -ENOMEM;
71 rep = nlmsg_new(sizeof(struct inet_diag_msg) +
72 sizeof(struct inet_diag_meminfo) + 64,
73 GFP_KERNEL);
74 if (!rep)
75 goto out;
76
77 err = inet_sk_diag_fill(sk, NULL, rep, req,
78 sk_user_ns(NETLINK_CB(in_skb).sk),
79 NETLINK_CB(in_skb).portid,
80 nlh->nlmsg_seq, 0, nlh,
81 netlink_net_capable(in_skb, CAP_NET_ADMIN));
82 if (err < 0) {
83 WARN_ON(err == -EMSGSIZE);
84 kfree_skb(rep);
85 goto out;
86 }
87 err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid,
88 MSG_DONTWAIT);
89 if (err > 0)
90 err = 0;
91 out:
92 if (sk)
93 sock_put(sk);
94 out_nosk:
95 return err;
96 }
97
98 static void udp_dump(struct udp_table *table, struct sk_buff *skb,
99 struct netlink_callback *cb,
100 const struct inet_diag_req_v2 *r, struct nlattr *bc)
101 {
102 bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
103 struct net *net = sock_net(skb->sk);
104 int num, s_num, slot, s_slot;
105
106 s_slot = cb->args[0];
107 num = s_num = cb->args[1];
108
109 for (slot = s_slot; slot <= table->mask; s_num = 0, slot++) {
110 struct udp_hslot *hslot = &table->hash[slot];
111 struct sock *sk;
112
113 num = 0;
114
115 if (hlist_empty(&hslot->head))
116 continue;
117
118 spin_lock_bh(&hslot->lock);
119 sk_for_each(sk, &hslot->head) {
120 struct inet_sock *inet = inet_sk(sk);
121
122 if (!net_eq(sock_net(sk), net))
123 continue;
124 if (num < s_num)
125 goto next;
126 if (!(r->idiag_states & (1 << sk->sk_state)))
127 goto next;
128 if (r->sdiag_family != AF_UNSPEC &&
129 sk->sk_family != r->sdiag_family)
130 goto next;
131 if (r->id.idiag_sport != inet->inet_sport &&
132 r->id.idiag_sport)
133 goto next;
134 if (r->id.idiag_dport != inet->inet_dport &&
135 r->id.idiag_dport)
136 goto next;
137
138 if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0) {
139 spin_unlock_bh(&hslot->lock);
140 goto done;
141 }
142 next:
143 num++;
144 }
145 spin_unlock_bh(&hslot->lock);
146 }
147 done:
148 cb->args[0] = slot;
149 cb->args[1] = num;
150 }
151
152 static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
153 const struct inet_diag_req_v2 *r, struct nlattr *bc)
154 {
155 udp_dump(&udp_table, skb, cb, r, bc);
156 }
157
158 static int udp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
159 const struct inet_diag_req_v2 *req)
160 {
161 return udp_dump_one(&udp_table, in_skb, nlh, req);
162 }
163
164 static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
165 void *info)
166 {
167 r->idiag_rqueue = udp_rqueue_get(sk);
168 r->idiag_wqueue = sk_wmem_alloc_get(sk);
169 }
170
171 #ifdef CONFIG_INET_DIAG_DESTROY
172 static int __udp_diag_destroy(struct sk_buff *in_skb,
173 const struct inet_diag_req_v2 *req,
174 struct udp_table *tbl)
175 {
176 struct net *net = sock_net(in_skb->sk);
177 struct sock *sk;
178 int err;
179
180 rcu_read_lock();
181
182 if (req->sdiag_family == AF_INET)
183 sk = __udp4_lib_lookup(net,
184 req->id.idiag_dst[0], req->id.idiag_dport,
185 req->id.idiag_src[0], req->id.idiag_sport,
186 req->id.idiag_if, 0, tbl, NULL);
187 #if IS_ENABLED(CONFIG_IPV6)
188 else if (req->sdiag_family == AF_INET6) {
189 if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) &&
190 ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src))
191 sk = __udp4_lib_lookup(net,
192 req->id.idiag_dst[3], req->id.idiag_dport,
193 req->id.idiag_src[3], req->id.idiag_sport,
194 req->id.idiag_if, 0, tbl, NULL);
195
196 else
197 sk = __udp6_lib_lookup(net,
198 (struct in6_addr *)req->id.idiag_dst,
199 req->id.idiag_dport,
200 (struct in6_addr *)req->id.idiag_src,
201 req->id.idiag_sport,
202 req->id.idiag_if, 0, tbl, NULL);
203 }
204 #endif
205 else {
206 rcu_read_unlock();
207 return -EINVAL;
208 }
209
210 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
211 sk = NULL;
212
213 rcu_read_unlock();
214
215 if (!sk)
216 return -ENOENT;
217
218 if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) {
219 sock_put(sk);
220 return -ENOENT;
221 }
222
223 err = sock_diag_destroy(sk, ECONNABORTED);
224
225 sock_put(sk);
226
227 return err;
228 }
229
230 static int udp_diag_destroy(struct sk_buff *in_skb,
231 const struct inet_diag_req_v2 *req)
232 {
233 return __udp_diag_destroy(in_skb, req, &udp_table);
234 }
235
236 static int udplite_diag_destroy(struct sk_buff *in_skb,
237 const struct inet_diag_req_v2 *req)
238 {
239 return __udp_diag_destroy(in_skb, req, &udplite_table);
240 }
241
242 #endif
243
244 static const struct inet_diag_handler udp_diag_handler = {
245 .dump = udp_diag_dump,
246 .dump_one = udp_diag_dump_one,
247 .idiag_get_info = udp_diag_get_info,
248 .idiag_type = IPPROTO_UDP,
249 .idiag_info_size = 0,
250 #ifdef CONFIG_INET_DIAG_DESTROY
251 .destroy = udp_diag_destroy,
252 #endif
253 };
254
255 static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
256 const struct inet_diag_req_v2 *r,
257 struct nlattr *bc)
258 {
259 udp_dump(&udplite_table, skb, cb, r, bc);
260 }
261
262 static int udplite_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
263 const struct inet_diag_req_v2 *req)
264 {
265 return udp_dump_one(&udplite_table, in_skb, nlh, req);
266 }
267
268 static const struct inet_diag_handler udplite_diag_handler = {
269 .dump = udplite_diag_dump,
270 .dump_one = udplite_diag_dump_one,
271 .idiag_get_info = udp_diag_get_info,
272 .idiag_type = IPPROTO_UDPLITE,
273 .idiag_info_size = 0,
274 #ifdef CONFIG_INET_DIAG_DESTROY
275 .destroy = udplite_diag_destroy,
276 #endif
277 };
278
279 static int __init udp_diag_init(void)
280 {
281 int err;
282
283 err = inet_diag_register(&udp_diag_handler);
284 if (err)
285 goto out;
286 err = inet_diag_register(&udplite_diag_handler);
287 if (err)
288 goto out_lite;
289 out:
290 return err;
291 out_lite:
292 inet_diag_unregister(&udp_diag_handler);
293 goto out;
294 }
295
296 static void __exit udp_diag_exit(void)
297 {
298 inet_diag_unregister(&udplite_diag_handler);
299 inet_diag_unregister(&udp_diag_handler);
300 }
301
302 module_init(udp_diag_init);
303 module_exit(udp_diag_exit);
304 MODULE_LICENSE("GPL");
305 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */);
306 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */);
307
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