xref: /openbmc/linux/net/ipv4/udp_diag.c (revision 9f380456)
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, struct inet_diag_req_v2 *req,
22 		struct nlattr *bc)
23 {
24 	if (!inet_diag_bc_sk(bc, sk))
25 		return 0;
26 
27 	return inet_sk_diag_fill(sk, NULL, skb, req, NETLINK_CB(cb->skb).pid,
28 			cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh);
29 }
30 
31 static int udp_dump_one(struct udp_table *tbl, struct sk_buff *in_skb,
32 		const struct nlmsghdr *nlh, struct inet_diag_req_v2 *req)
33 {
34 	int err = -EINVAL;
35 	struct sock *sk;
36 	struct sk_buff *rep;
37 
38 	if (req->sdiag_family == AF_INET)
39 		sk = __udp4_lib_lookup(&init_net,
40 				req->id.idiag_src[0], req->id.idiag_sport,
41 				req->id.idiag_dst[0], req->id.idiag_dport,
42 				req->id.idiag_if, tbl);
43 #if IS_ENABLED(CONFIG_IPV6)
44 	else if (req->sdiag_family == AF_INET6)
45 		sk = __udp6_lib_lookup(&init_net,
46 				(struct in6_addr *)req->id.idiag_src,
47 				req->id.idiag_sport,
48 				(struct in6_addr *)req->id.idiag_dst,
49 				req->id.idiag_dport,
50 				req->id.idiag_if, tbl);
51 #endif
52 	else
53 		goto out_nosk;
54 
55 	err = -ENOENT;
56 	if (sk == NULL)
57 		goto out_nosk;
58 
59 	err = sock_diag_check_cookie(sk, req->id.idiag_cookie);
60 	if (err)
61 		goto out;
62 
63 	err = -ENOMEM;
64 	rep = alloc_skb(NLMSG_SPACE((sizeof(struct inet_diag_msg) +
65 				     sizeof(struct inet_diag_meminfo) +
66 				     64)), GFP_KERNEL);
67 	if (!rep)
68 		goto out;
69 
70 	err = inet_sk_diag_fill(sk, NULL, rep, req,
71 			   NETLINK_CB(in_skb).pid,
72 			   nlh->nlmsg_seq, 0, nlh);
73 	if (err < 0) {
74 		WARN_ON(err == -EMSGSIZE);
75 		kfree_skb(rep);
76 		goto out;
77 	}
78 	err = netlink_unicast(sock_diag_nlsk, rep, NETLINK_CB(in_skb).pid,
79 			      MSG_DONTWAIT);
80 	if (err > 0)
81 		err = 0;
82 out:
83 	if (sk)
84 		sock_put(sk);
85 out_nosk:
86 	return err;
87 }
88 
89 static void udp_dump(struct udp_table *table, struct sk_buff *skb, struct netlink_callback *cb,
90 		struct inet_diag_req_v2 *r, struct nlattr *bc)
91 {
92 	int num, s_num, slot, s_slot;
93 
94 	s_slot = cb->args[0];
95 	num = s_num = cb->args[1];
96 
97 	for (slot = s_slot; slot <= table->mask; num = s_num = 0, slot++) {
98 		struct sock *sk;
99 		struct hlist_nulls_node *node;
100 		struct udp_hslot *hslot = &table->hash[slot];
101 
102 		if (hlist_nulls_empty(&hslot->head))
103 			continue;
104 
105 		spin_lock_bh(&hslot->lock);
106 		sk_nulls_for_each(sk, node, &hslot->head) {
107 			struct inet_sock *inet = inet_sk(sk);
108 
109 			if (num < s_num)
110 				goto next;
111 			if (!(r->idiag_states & (1 << sk->sk_state)))
112 				goto next;
113 			if (r->sdiag_family != AF_UNSPEC &&
114 					sk->sk_family != r->sdiag_family)
115 				goto next;
116 			if (r->id.idiag_sport != inet->inet_sport &&
117 			    r->id.idiag_sport)
118 				goto next;
119 			if (r->id.idiag_dport != inet->inet_dport &&
120 			    r->id.idiag_dport)
121 				goto next;
122 
123 			if (sk_diag_dump(sk, skb, cb, r, bc) < 0) {
124 				spin_unlock_bh(&hslot->lock);
125 				goto done;
126 			}
127 next:
128 			num++;
129 		}
130 		spin_unlock_bh(&hslot->lock);
131 	}
132 done:
133 	cb->args[0] = slot;
134 	cb->args[1] = num;
135 }
136 
137 static void udp_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
138 		struct inet_diag_req_v2 *r, struct nlattr *bc)
139 {
140 	udp_dump(&udp_table, skb, cb, r, bc);
141 }
142 
143 static int udp_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
144 		struct inet_diag_req_v2 *req)
145 {
146 	return udp_dump_one(&udp_table, in_skb, nlh, req);
147 }
148 
149 static void udp_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
150 		void *info)
151 {
152 	r->idiag_rqueue = sk_rmem_alloc_get(sk);
153 	r->idiag_wqueue = sk_wmem_alloc_get(sk);
154 }
155 
156 static const struct inet_diag_handler udp_diag_handler = {
157 	.dump		 = udp_diag_dump,
158 	.dump_one	 = udp_diag_dump_one,
159 	.idiag_get_info  = udp_diag_get_info,
160 	.idiag_type	 = IPPROTO_UDP,
161 };
162 
163 static void udplite_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
164 		struct inet_diag_req_v2 *r, struct nlattr *bc)
165 {
166 	udp_dump(&udplite_table, skb, cb, r, bc);
167 }
168 
169 static int udplite_diag_dump_one(struct sk_buff *in_skb, const struct nlmsghdr *nlh,
170 		struct inet_diag_req_v2 *req)
171 {
172 	return udp_dump_one(&udplite_table, in_skb, nlh, req);
173 }
174 
175 static const struct inet_diag_handler udplite_diag_handler = {
176 	.dump		 = udplite_diag_dump,
177 	.dump_one	 = udplite_diag_dump_one,
178 	.idiag_get_info  = udp_diag_get_info,
179 	.idiag_type	 = IPPROTO_UDPLITE,
180 };
181 
182 static int __init udp_diag_init(void)
183 {
184 	int err;
185 
186 	err = inet_diag_register(&udp_diag_handler);
187 	if (err)
188 		goto out;
189 	err = inet_diag_register(&udplite_diag_handler);
190 	if (err)
191 		goto out_lite;
192 out:
193 	return err;
194 out_lite:
195 	inet_diag_unregister(&udp_diag_handler);
196 	goto out;
197 }
198 
199 static void __exit udp_diag_exit(void)
200 {
201 	inet_diag_unregister(&udplite_diag_handler);
202 	inet_diag_unregister(&udp_diag_handler);
203 }
204 
205 module_init(udp_diag_init);
206 module_exit(udp_diag_exit);
207 MODULE_LICENSE("GPL");
208 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-17 /* AF_INET - IPPROTO_UDP */);
209 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-136 /* AF_INET - IPPROTO_UDPLITE */);
210