xref: /kernel/linux/linux-5.10/net/ipv4/raw_diag.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0-only
2#include <linux/module.h>
3
4#include <linux/inet_diag.h>
5#include <linux/sock_diag.h>
6
7#include <net/inet_sock.h>
8#include <net/raw.h>
9#include <net/rawv6.h>
10
11#ifdef pr_fmt
12# undef pr_fmt
13#endif
14
15#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16
17static struct raw_hashinfo *
18raw_get_hashinfo(const struct inet_diag_req_v2 *r)
19{
20	if (r->sdiag_family == AF_INET) {
21		return &raw_v4_hashinfo;
22#if IS_ENABLED(CONFIG_IPV6)
23	} else if (r->sdiag_family == AF_INET6) {
24		return &raw_v6_hashinfo;
25#endif
26	} else {
27		return ERR_PTR(-EINVAL);
28	}
29}
30
31/*
32 * Due to requirement of not breaking user API we can't simply
33 * rename @pad field in inet_diag_req_v2 structure, instead
34 * use helper to figure it out.
35 */
36
37static struct sock *raw_lookup(struct net *net, struct sock *from,
38			       const struct inet_diag_req_v2 *req)
39{
40	struct inet_diag_req_raw *r = (void *)req;
41	struct sock *sk = NULL;
42
43	if (r->sdiag_family == AF_INET)
44		sk = __raw_v4_lookup(net, from, r->sdiag_raw_protocol,
45				     r->id.idiag_dst[0],
46				     r->id.idiag_src[0],
47				     r->id.idiag_if, 0);
48#if IS_ENABLED(CONFIG_IPV6)
49	else
50		sk = __raw_v6_lookup(net, from, r->sdiag_raw_protocol,
51				     (const struct in6_addr *)r->id.idiag_src,
52				     (const struct in6_addr *)r->id.idiag_dst,
53				     r->id.idiag_if, 0);
54#endif
55	return sk;
56}
57
58static struct sock *raw_sock_get(struct net *net, const struct inet_diag_req_v2 *r)
59{
60	struct raw_hashinfo *hashinfo = raw_get_hashinfo(r);
61	struct sock *sk = NULL, *s;
62	int slot;
63
64	if (IS_ERR(hashinfo))
65		return ERR_CAST(hashinfo);
66
67	read_lock(&hashinfo->lock);
68	for (slot = 0; slot < RAW_HTABLE_SIZE; slot++) {
69		sk_for_each(s, &hashinfo->ht[slot]) {
70			sk = raw_lookup(net, s, r);
71			if (sk) {
72				/*
73				 * Grab it and keep until we fill
74				 * diag meaage to be reported, so
75				 * caller should call sock_put then.
76				 * We can do that because we're keeping
77				 * hashinfo->lock here.
78				 */
79				sock_hold(sk);
80				goto out_unlock;
81			}
82		}
83	}
84out_unlock:
85	read_unlock(&hashinfo->lock);
86
87	return sk ? sk : ERR_PTR(-ENOENT);
88}
89
90static int raw_diag_dump_one(struct netlink_callback *cb,
91			     const struct inet_diag_req_v2 *r)
92{
93	struct sk_buff *in_skb = cb->skb;
94	struct sk_buff *rep;
95	struct sock *sk;
96	struct net *net;
97	int err;
98
99	net = sock_net(in_skb->sk);
100	sk = raw_sock_get(net, r);
101	if (IS_ERR(sk))
102		return PTR_ERR(sk);
103
104	rep = nlmsg_new(nla_total_size(sizeof(struct inet_diag_msg)) +
105			inet_diag_msg_attrs_size() +
106			nla_total_size(sizeof(struct inet_diag_meminfo)) + 64,
107			GFP_KERNEL);
108	if (!rep) {
109		sock_put(sk);
110		return -ENOMEM;
111	}
112
113	err = inet_sk_diag_fill(sk, NULL, rep, cb, r, 0,
114				netlink_net_capable(in_skb, CAP_NET_ADMIN));
115	sock_put(sk);
116
117	if (err < 0) {
118		kfree_skb(rep);
119		return err;
120	}
121
122	err = netlink_unicast(net->diag_nlsk, rep,
123			      NETLINK_CB(in_skb).portid,
124			      MSG_DONTWAIT);
125	if (err > 0)
126		err = 0;
127	return err;
128}
129
130static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
131			struct netlink_callback *cb,
132			const struct inet_diag_req_v2 *r,
133			struct nlattr *bc, bool net_admin)
134{
135	if (!inet_diag_bc_sk(bc, sk))
136		return 0;
137
138	return inet_sk_diag_fill(sk, NULL, skb, cb, r, NLM_F_MULTI, net_admin);
139}
140
141static void raw_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
142			  const struct inet_diag_req_v2 *r)
143{
144	bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
145	struct raw_hashinfo *hashinfo = raw_get_hashinfo(r);
146	struct net *net = sock_net(skb->sk);
147	struct inet_diag_dump_data *cb_data;
148	int num, s_num, slot, s_slot;
149	struct sock *sk = NULL;
150	struct nlattr *bc;
151
152	if (IS_ERR(hashinfo))
153		return;
154
155	cb_data = cb->data;
156	bc = cb_data->inet_diag_nla_bc;
157	s_slot = cb->args[0];
158	num = s_num = cb->args[1];
159
160	read_lock(&hashinfo->lock);
161	for (slot = s_slot; slot < RAW_HTABLE_SIZE; s_num = 0, slot++) {
162		num = 0;
163
164		sk_for_each(sk, &hashinfo->ht[slot]) {
165			struct inet_sock *inet = inet_sk(sk);
166
167			if (!net_eq(sock_net(sk), net))
168				continue;
169			if (num < s_num)
170				goto next;
171			if (sk->sk_family != r->sdiag_family)
172				goto next;
173			if (r->id.idiag_sport != inet->inet_sport &&
174			    r->id.idiag_sport)
175				goto next;
176			if (r->id.idiag_dport != inet->inet_dport &&
177			    r->id.idiag_dport)
178				goto next;
179			if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0)
180				goto out_unlock;
181next:
182			num++;
183		}
184	}
185
186out_unlock:
187	read_unlock(&hashinfo->lock);
188
189	cb->args[0] = slot;
190	cb->args[1] = num;
191}
192
193static void raw_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
194			      void *info)
195{
196	r->idiag_rqueue = sk_rmem_alloc_get(sk);
197	r->idiag_wqueue = sk_wmem_alloc_get(sk);
198}
199
200#ifdef CONFIG_INET_DIAG_DESTROY
201static int raw_diag_destroy(struct sk_buff *in_skb,
202			    const struct inet_diag_req_v2 *r)
203{
204	struct net *net = sock_net(in_skb->sk);
205	struct sock *sk;
206	int err;
207
208	sk = raw_sock_get(net, r);
209	if (IS_ERR(sk))
210		return PTR_ERR(sk);
211	err = sock_diag_destroy(sk, ECONNABORTED);
212	sock_put(sk);
213	return err;
214}
215#endif
216
217static const struct inet_diag_handler raw_diag_handler = {
218	.dump			= raw_diag_dump,
219	.dump_one		= raw_diag_dump_one,
220	.idiag_get_info		= raw_diag_get_info,
221	.idiag_type		= IPPROTO_RAW,
222	.idiag_info_size	= 0,
223#ifdef CONFIG_INET_DIAG_DESTROY
224	.destroy		= raw_diag_destroy,
225#endif
226};
227
228static void __always_unused __check_inet_diag_req_raw(void)
229{
230	/*
231	 * Make sure the two structures are identical,
232	 * except the @pad field.
233	 */
234#define __offset_mismatch(m1, m2)			\
235	(offsetof(struct inet_diag_req_v2, m1) !=	\
236	 offsetof(struct inet_diag_req_raw, m2))
237
238	BUILD_BUG_ON(sizeof(struct inet_diag_req_v2) !=
239		     sizeof(struct inet_diag_req_raw));
240	BUILD_BUG_ON(__offset_mismatch(sdiag_family, sdiag_family));
241	BUILD_BUG_ON(__offset_mismatch(sdiag_protocol, sdiag_protocol));
242	BUILD_BUG_ON(__offset_mismatch(idiag_ext, idiag_ext));
243	BUILD_BUG_ON(__offset_mismatch(pad, sdiag_raw_protocol));
244	BUILD_BUG_ON(__offset_mismatch(idiag_states, idiag_states));
245	BUILD_BUG_ON(__offset_mismatch(id, id));
246#undef __offset_mismatch
247}
248
249static int __init raw_diag_init(void)
250{
251	return inet_diag_register(&raw_diag_handler);
252}
253
254static void __exit raw_diag_exit(void)
255{
256	inet_diag_unregister(&raw_diag_handler);
257}
258
259module_init(raw_diag_init);
260module_exit(raw_diag_exit);
261MODULE_LICENSE("GPL");
262MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2-255 /* AF_INET - IPPROTO_RAW */);
263MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 10-255 /* AF_INET6 - IPPROTO_RAW */);
264