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
sk_diag_dump(struct sock * sk,struct sk_buff * skb,struct netlink_callback * cb,const struct inet_diag_req_v2 * req,struct nlattr * bc,bool net_admin)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, cb, req, NLM_F_MULTI,
25 net_admin);
26 }
27
udp_dump_one(struct udp_table * tbl,struct netlink_callback * cb,const struct inet_diag_req_v2 * req)28 static int udp_dump_one(struct udp_table *tbl,
29 struct netlink_callback *cb,
30 const struct inet_diag_req_v2 *req)
31 {
32 struct sk_buff *in_skb = cb->skb;
33 int err = -EINVAL;
34 struct sock *sk = NULL;
35 struct sk_buff *rep;
36 struct net *net = sock_net(in_skb->sk);
37
38 rcu_read_lock();
39 if (req->sdiag_family == AF_INET)
40 /* src and dst are swapped for historical reasons */
41 sk = __udp4_lib_lookup(net,
42 req->id.idiag_src[0], req->id.idiag_sport,
43 req->id.idiag_dst[0], req->id.idiag_dport,
44 req->id.idiag_if, 0, tbl, NULL);
45 #if IS_ENABLED(CONFIG_IPV6)
46 else if (req->sdiag_family == AF_INET6)
47 sk = __udp6_lib_lookup(net,
48 (struct in6_addr *)req->id.idiag_src,
49 req->id.idiag_sport,
50 (struct in6_addr *)req->id.idiag_dst,
51 req->id.idiag_dport,
52 req->id.idiag_if, 0, tbl, NULL);
53 #endif
54 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
55 sk = NULL;
56 rcu_read_unlock();
57 err = -ENOENT;
58 if (!sk)
59 goto out_nosk;
60
61 err = sock_diag_check_cookie(sk, req->id.idiag_cookie);
62 if (err)
63 goto out;
64
65 err = -ENOMEM;
66 rep = nlmsg_new(nla_total_size(sizeof(struct inet_diag_msg)) +
67 inet_diag_msg_attrs_size() +
68 nla_total_size(sizeof(struct inet_diag_meminfo)) + 64,
69 GFP_KERNEL);
70 if (!rep)
71 goto out;
72
73 err = inet_sk_diag_fill(sk, NULL, rep, cb, req, 0,
74 netlink_net_capable(in_skb, CAP_NET_ADMIN));
75 if (err < 0) {
76 WARN_ON(err == -EMSGSIZE);
77 kfree_skb(rep);
78 goto out;
79 }
80 err = netlink_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid,
81 MSG_DONTWAIT);
82 if (err > 0)
83 err = 0;
84 out:
85 if (sk)
86 sock_put(sk);
87 out_nosk:
88 return err;
89 }
90
udp_dump(struct udp_table * table,struct sk_buff * skb,struct netlink_callback * cb,const struct inet_diag_req_v2 * r)91 static void udp_dump(struct udp_table *table, struct sk_buff *skb,
92 struct netlink_callback *cb,
93 const struct inet_diag_req_v2 *r)
94 {
95 bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
96 struct net *net = sock_net(skb->sk);
97 struct inet_diag_dump_data *cb_data;
98 int num, s_num, slot, s_slot;
99 struct nlattr *bc;
100
101 cb_data = cb->data;
102 bc = cb_data->inet_diag_nla_bc;
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
udp_diag_dump(struct sk_buff * skb,struct netlink_callback * cb,const struct inet_diag_req_v2 * r)149 static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
150 const struct inet_diag_req_v2 *r)
151 {
152 udp_dump(&udp_table, skb, cb, r);
153 }
154
udp_diag_dump_one(struct netlink_callback * cb,const struct inet_diag_req_v2 * req)155 static int udp_diag_dump_one(struct netlink_callback *cb,
156 const struct inet_diag_req_v2 *req)
157 {
158 return udp_dump_one(&udp_table, cb, req);
159 }
160
udp_diag_get_info(struct sock * sk,struct inet_diag_msg * r,void * info)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
__udp_diag_destroy(struct sk_buff * in_skb,const struct inet_diag_req_v2 * req,struct udp_table * tbl)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
udp_diag_destroy(struct sk_buff * in_skb,const struct inet_diag_req_v2 * req)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
udplite_diag_destroy(struct sk_buff * in_skb,const struct inet_diag_req_v2 * req)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
udplite_diag_dump(struct sk_buff * skb,struct netlink_callback * cb,const struct inet_diag_req_v2 * r)252 static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
253 const struct inet_diag_req_v2 *r)
254 {
255 udp_dump(&udplite_table, skb, cb, r);
256 }
257
udplite_diag_dump_one(struct netlink_callback * cb,const struct inet_diag_req_v2 * req)258 static int udplite_diag_dump_one(struct netlink_callback *cb,
259 const struct inet_diag_req_v2 *req)
260 {
261 return udp_dump_one(&udplite_table, cb, req);
262 }
263
264 static const struct inet_diag_handler udplite_diag_handler = {
265 .dump = udplite_diag_dump,
266 .dump_one = udplite_diag_dump_one,
267 .idiag_get_info = udp_diag_get_info,
268 .idiag_type = IPPROTO_UDPLITE,
269 .idiag_info_size = 0,
270 #ifdef CONFIG_INET_DIAG_DESTROY
271 .destroy = udplite_diag_destroy,
272 #endif
273 };
274
udp_diag_init(void)275 static int __init udp_diag_init(void)
276 {
277 int err;
278
279 err = inet_diag_register(&udp_diag_handler);
280 if (err)
281 goto out;
282 err = inet_diag_register(&udplite_diag_handler);
283 if (err)
284 goto out_lite;
285 out:
286 return err;
287 out_lite:
288 inet_diag_unregister(&udp_diag_handler);
289 goto out;
290 }
291
udp_diag_exit(void)292 static void __exit udp_diag_exit(void)
293 {
294 inet_diag_unregister(&udplite_diag_handler);
295 inet_diag_unregister(&udp_diag_handler);
296 }
297
298 module_init(udp_diag_init);
299 module_exit(udp_diag_exit);
300 MODULE_LICENSE("GPL");
301 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */);
302 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */);
303