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