1#include <linux/module.h>
2
3#include <net/sock.h>
4#include <linux/netlink.h>
5#include <linux/sock_diag.h>
6#include <linux/netlink_diag.h>
7#include <linux/rhashtable.h>
8
9#include "af_netlink.h"
10
11#ifdef CONFIG_NETLINK_MMAP
12static int sk_diag_put_ring(struct netlink_ring *ring, int nl_type,
13			    struct sk_buff *nlskb)
14{
15	struct netlink_diag_ring ndr;
16
17	ndr.ndr_block_size = ring->pg_vec_pages << PAGE_SHIFT;
18	ndr.ndr_block_nr   = ring->pg_vec_len;
19	ndr.ndr_frame_size = ring->frame_size;
20	ndr.ndr_frame_nr   = ring->frame_max + 1;
21
22	return nla_put(nlskb, nl_type, sizeof(ndr), &ndr);
23}
24
25static int sk_diag_put_rings_cfg(struct sock *sk, struct sk_buff *nlskb)
26{
27	struct netlink_sock *nlk = nlk_sk(sk);
28	int ret;
29
30	mutex_lock(&nlk->pg_vec_lock);
31	ret = sk_diag_put_ring(&nlk->rx_ring, NETLINK_DIAG_RX_RING, nlskb);
32	if (!ret)
33		ret = sk_diag_put_ring(&nlk->tx_ring, NETLINK_DIAG_TX_RING,
34				       nlskb);
35	mutex_unlock(&nlk->pg_vec_lock);
36
37	return ret;
38}
39#else
40static int sk_diag_put_rings_cfg(struct sock *sk, struct sk_buff *nlskb)
41{
42	return 0;
43}
44#endif
45
46static int sk_diag_dump_groups(struct sock *sk, struct sk_buff *nlskb)
47{
48	struct netlink_sock *nlk = nlk_sk(sk);
49
50	if (nlk->groups == NULL)
51		return 0;
52
53	return nla_put(nlskb, NETLINK_DIAG_GROUPS, NLGRPSZ(nlk->ngroups),
54		       nlk->groups);
55}
56
57static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
58			struct netlink_diag_req *req,
59			u32 portid, u32 seq, u32 flags, int sk_ino)
60{
61	struct nlmsghdr *nlh;
62	struct netlink_diag_msg *rep;
63	struct netlink_sock *nlk = nlk_sk(sk);
64
65	nlh = nlmsg_put(skb, portid, seq, SOCK_DIAG_BY_FAMILY, sizeof(*rep),
66			flags);
67	if (!nlh)
68		return -EMSGSIZE;
69
70	rep = nlmsg_data(nlh);
71	rep->ndiag_family	= AF_NETLINK;
72	rep->ndiag_type		= sk->sk_type;
73	rep->ndiag_protocol	= sk->sk_protocol;
74	rep->ndiag_state	= sk->sk_state;
75
76	rep->ndiag_ino		= sk_ino;
77	rep->ndiag_portid	= nlk->portid;
78	rep->ndiag_dst_portid	= nlk->dst_portid;
79	rep->ndiag_dst_group	= nlk->dst_group;
80	sock_diag_save_cookie(sk, rep->ndiag_cookie);
81
82	if ((req->ndiag_show & NDIAG_SHOW_GROUPS) &&
83	    sk_diag_dump_groups(sk, skb))
84		goto out_nlmsg_trim;
85
86	if ((req->ndiag_show & NDIAG_SHOW_MEMINFO) &&
87	    sock_diag_put_meminfo(sk, skb, NETLINK_DIAG_MEMINFO))
88		goto out_nlmsg_trim;
89
90	if ((req->ndiag_show & NDIAG_SHOW_RING_CFG) &&
91	    sk_diag_put_rings_cfg(sk, skb))
92		goto out_nlmsg_trim;
93
94	nlmsg_end(skb, nlh);
95	return 0;
96
97out_nlmsg_trim:
98	nlmsg_cancel(skb, nlh);
99	return -EMSGSIZE;
100}
101
102static int __netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
103				int protocol, int s_num)
104{
105	struct netlink_table *tbl = &nl_table[protocol];
106	struct rhashtable *ht = &tbl->hash;
107	const struct bucket_table *htbl = rht_dereference_rcu(ht->tbl, ht);
108	struct net *net = sock_net(skb->sk);
109	struct netlink_diag_req *req;
110	struct netlink_sock *nlsk;
111	struct sock *sk;
112	int ret = 0, num = 0, i;
113
114	req = nlmsg_data(cb->nlh);
115
116	for (i = 0; i < htbl->size; i++) {
117		struct rhash_head *pos;
118
119		rht_for_each_entry_rcu(nlsk, pos, htbl, i, node) {
120			sk = (struct sock *)nlsk;
121
122			if (!net_eq(sock_net(sk), net))
123				continue;
124			if (num < s_num) {
125				num++;
126				continue;
127			}
128
129			if (sk_diag_fill(sk, skb, req,
130					 NETLINK_CB(cb->skb).portid,
131					 cb->nlh->nlmsg_seq,
132					 NLM_F_MULTI,
133					 sock_i_ino(sk)) < 0) {
134				ret = 1;
135				goto done;
136			}
137
138			num++;
139		}
140	}
141
142	sk_for_each_bound(sk, &tbl->mc_list) {
143		if (sk_hashed(sk))
144			continue;
145		if (!net_eq(sock_net(sk), net))
146			continue;
147		if (num < s_num) {
148			num++;
149			continue;
150		}
151
152		if (sk_diag_fill(sk, skb, req,
153				 NETLINK_CB(cb->skb).portid,
154				 cb->nlh->nlmsg_seq,
155				 NLM_F_MULTI,
156				 sock_i_ino(sk)) < 0) {
157			ret = 1;
158			goto done;
159		}
160		num++;
161	}
162done:
163	cb->args[0] = num;
164	cb->args[1] = protocol;
165
166	return ret;
167}
168
169static int netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
170{
171	struct netlink_diag_req *req;
172	int s_num = cb->args[0];
173
174	req = nlmsg_data(cb->nlh);
175
176	rcu_read_lock();
177	read_lock(&nl_table_lock);
178
179	if (req->sdiag_protocol == NDIAG_PROTO_ALL) {
180		int i;
181
182		for (i = cb->args[1]; i < MAX_LINKS; i++) {
183			if (__netlink_diag_dump(skb, cb, i, s_num))
184				break;
185			s_num = 0;
186		}
187	} else {
188		if (req->sdiag_protocol >= MAX_LINKS) {
189			read_unlock(&nl_table_lock);
190			rcu_read_unlock();
191			return -ENOENT;
192		}
193
194		__netlink_diag_dump(skb, cb, req->sdiag_protocol, s_num);
195	}
196
197	read_unlock(&nl_table_lock);
198	rcu_read_unlock();
199
200	return skb->len;
201}
202
203static int netlink_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
204{
205	int hdrlen = sizeof(struct netlink_diag_req);
206	struct net *net = sock_net(skb->sk);
207
208	if (nlmsg_len(h) < hdrlen)
209		return -EINVAL;
210
211	if (h->nlmsg_flags & NLM_F_DUMP) {
212		struct netlink_dump_control c = {
213			.dump = netlink_diag_dump,
214		};
215		return netlink_dump_start(net->diag_nlsk, skb, h, &c);
216	} else
217		return -EOPNOTSUPP;
218}
219
220static const struct sock_diag_handler netlink_diag_handler = {
221	.family = AF_NETLINK,
222	.dump = netlink_diag_handler_dump,
223};
224
225static int __init netlink_diag_init(void)
226{
227	return sock_diag_register(&netlink_diag_handler);
228}
229
230static void __exit netlink_diag_exit(void)
231{
232	sock_diag_unregister(&netlink_diag_handler);
233}
234
235module_init(netlink_diag_init);
236module_exit(netlink_diag_exit);
237MODULE_LICENSE("GPL");
238MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 16 /* AF_NETLINK */);
239