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 bool raw_lookup(struct net *net, const struct sock *sk,
38		       const struct inet_diag_req_v2 *req)
39{
40	struct inet_diag_req_raw *r = (void *)req;
41
42	if (r->sdiag_family == AF_INET)
43		return raw_v4_match(net, sk, r->sdiag_raw_protocol,
44				    r->id.idiag_dst[0],
45				    r->id.idiag_src[0],
46				    r->id.idiag_if, 0);
47#if IS_ENABLED(CONFIG_IPV6)
48	else
49		return raw_v6_match(net, sk, r->sdiag_raw_protocol,
50				    (const struct in6_addr *)r->id.idiag_src,
51				    (const struct in6_addr *)r->id.idiag_dst,
52				    r->id.idiag_if, 0);
53#endif
54	return false;
55}
56
57static struct sock *raw_sock_get(struct net *net, const struct inet_diag_req_v2 *r)
58{
59	struct raw_hashinfo *hashinfo = raw_get_hashinfo(r);
60	struct hlist_head *hlist;
61	struct sock *sk;
62	int slot;
63
64	if (IS_ERR(hashinfo))
65		return ERR_CAST(hashinfo);
66
67	rcu_read_lock();
68	for (slot = 0; slot < RAW_HTABLE_SIZE; slot++) {
69		hlist = &hashinfo->ht[slot];
70		sk_for_each_rcu(sk, hlist) {
71			if (raw_lookup(net, sk, r)) {
72				/*
73				 * Grab it and keep until we fill
74				 * diag message to be reported, so
75				 * caller should call sock_put then.
76				 */
77				if (refcount_inc_not_zero(&sk->sk_refcnt))
78					goto out_unlock;
79			}
80		}
81	}
82	sk = ERR_PTR(-ENOENT);
83out_unlock:
84	rcu_read_unlock();
85
86	return sk;
87}
88
89static int raw_diag_dump_one(struct netlink_callback *cb,
90			     const struct inet_diag_req_v2 *r)
91{
92	struct sk_buff *in_skb = cb->skb;
93	struct sk_buff *rep;
94	struct sock *sk;
95	struct net *net;
96	int err;
97
98	net = sock_net(in_skb->sk);
99	sk = raw_sock_get(net, r);
100	if (IS_ERR(sk))
101		return PTR_ERR(sk);
102
103	rep = nlmsg_new(nla_total_size(sizeof(struct inet_diag_msg)) +
104			inet_diag_msg_attrs_size() +
105			nla_total_size(sizeof(struct inet_diag_meminfo)) + 64,
106			GFP_KERNEL);
107	if (!rep) {
108		sock_put(sk);
109		return -ENOMEM;
110	}
111
112	err = inet_sk_diag_fill(sk, NULL, rep, cb, r, 0,
113				netlink_net_capable(in_skb, CAP_NET_ADMIN));
114	sock_put(sk);
115
116	if (err < 0) {
117		kfree_skb(rep);
118		return err;
119	}
120
121	err = nlmsg_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid);
122
123	return err;
124}
125
126static int sk_diag_dump(struct sock *sk, struct sk_buff *skb,
127			struct netlink_callback *cb,
128			const struct inet_diag_req_v2 *r,
129			struct nlattr *bc, bool net_admin)
130{
131	if (!inet_diag_bc_sk(bc, sk))
132		return 0;
133
134	return inet_sk_diag_fill(sk, NULL, skb, cb, r, NLM_F_MULTI, net_admin);
135}
136
137static void raw_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
138			  const struct inet_diag_req_v2 *r)
139{
140	bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
141	struct raw_hashinfo *hashinfo = raw_get_hashinfo(r);
142	struct net *net = sock_net(skb->sk);
143	struct inet_diag_dump_data *cb_data;
144	int num, s_num, slot, s_slot;
145	struct hlist_head *hlist;
146	struct sock *sk = NULL;
147	struct nlattr *bc;
148
149	if (IS_ERR(hashinfo))
150		return;
151
152	cb_data = cb->data;
153	bc = cb_data->inet_diag_nla_bc;
154	s_slot = cb->args[0];
155	num = s_num = cb->args[1];
156
157	rcu_read_lock();
158	for (slot = s_slot; slot < RAW_HTABLE_SIZE; s_num = 0, slot++) {
159		num = 0;
160
161		hlist = &hashinfo->ht[slot];
162		sk_for_each_rcu(sk, hlist) {
163			struct inet_sock *inet = inet_sk(sk);
164
165			if (!net_eq(sock_net(sk), net))
166				continue;
167			if (num < s_num)
168				goto next;
169			if (sk->sk_family != r->sdiag_family)
170				goto next;
171			if (r->id.idiag_sport != inet->inet_sport &&
172			    r->id.idiag_sport)
173				goto next;
174			if (r->id.idiag_dport != inet->inet_dport &&
175			    r->id.idiag_dport)
176				goto next;
177			if (sk_diag_dump(sk, skb, cb, r, bc, net_admin) < 0)
178				goto out_unlock;
179next:
180			num++;
181		}
182	}
183
184out_unlock:
185	rcu_read_unlock();
186
187	cb->args[0] = slot;
188	cb->args[1] = num;
189}
190
191static void raw_diag_get_info(struct sock *sk, struct inet_diag_msg *r,
192			      void *info)
193{
194	r->idiag_rqueue = sk_rmem_alloc_get(sk);
195	r->idiag_wqueue = sk_wmem_alloc_get(sk);
196}
197
198#ifdef CONFIG_INET_DIAG_DESTROY
199static int raw_diag_destroy(struct sk_buff *in_skb,
200			    const struct inet_diag_req_v2 *r)
201{
202	struct net *net = sock_net(in_skb->sk);
203	struct sock *sk;
204	int err;
205
206	sk = raw_sock_get(net, r);
207	if (IS_ERR(sk))
208		return PTR_ERR(sk);
209	err = sock_diag_destroy(sk, ECONNABORTED);
210	sock_put(sk);
211	return err;
212}
213#endif
214
215static const struct inet_diag_handler raw_diag_handler = {
216	.owner			= THIS_MODULE,
217	.dump			= raw_diag_dump,
218	.dump_one		= raw_diag_dump_one,
219	.idiag_get_info		= raw_diag_get_info,
220	.idiag_type		= IPPROTO_RAW,
221	.idiag_info_size	= 0,
222#ifdef CONFIG_INET_DIAG_DESTROY
223	.destroy		= raw_diag_destroy,
224#endif
225};
226
227static void __always_unused __check_inet_diag_req_raw(void)
228{
229	/*
230	 * Make sure the two structures are identical,
231	 * except the @pad field.
232	 */
233#define __offset_mismatch(m1, m2)			\
234	(offsetof(struct inet_diag_req_v2, m1) !=	\
235	 offsetof(struct inet_diag_req_raw, m2))
236
237	BUILD_BUG_ON(sizeof(struct inet_diag_req_v2) !=
238		     sizeof(struct inet_diag_req_raw));
239	BUILD_BUG_ON(__offset_mismatch(sdiag_family, sdiag_family));
240	BUILD_BUG_ON(__offset_mismatch(sdiag_protocol, sdiag_protocol));
241	BUILD_BUG_ON(__offset_mismatch(idiag_ext, idiag_ext));
242	BUILD_BUG_ON(__offset_mismatch(pad, sdiag_raw_protocol));
243	BUILD_BUG_ON(__offset_mismatch(idiag_states, idiag_states));
244	BUILD_BUG_ON(__offset_mismatch(id, id));
245#undef __offset_mismatch
246}
247
248static int __init raw_diag_init(void)
249{
250	return inet_diag_register(&raw_diag_handler);
251}
252
253static void __exit raw_diag_exit(void)
254{
255	inet_diag_unregister(&raw_diag_handler);
256}
257
258module_init(raw_diag_init);
259module_exit(raw_diag_exit);
260MODULE_LICENSE("GPL");
261MODULE_DESCRIPTION("RAW socket monitoring via SOCK_DIAG");
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