1#include <linux/mutex.h>
2#include <linux/socket.h>
3#include <linux/skbuff.h>
4#include <net/netlink.h>
5#include <net/net_namespace.h>
6#include <linux/module.h>
7#include <net/sock.h>
8#include <linux/kernel.h>
9#include <linux/tcp.h>
10#include <linux/workqueue.h>
11
12#include <linux/inet_diag.h>
13#include <linux/sock_diag.h>
14
15static const struct sock_diag_handler *sock_diag_handlers[AF_MAX];
16static int (*inet_rcv_compat)(struct sk_buff *skb, struct nlmsghdr *nlh);
17static DEFINE_MUTEX(sock_diag_table_mutex);
18static struct workqueue_struct *broadcast_wq;
19
20static u64 sock_gen_cookie(struct sock *sk)
21{
22 while (1) {
23 u64 res = atomic64_read(&sk->sk_cookie);
24
25 if (res)
26 return res;
27 res = atomic64_inc_return(&sock_net(sk)->cookie_gen);
28 atomic64_cmpxchg(&sk->sk_cookie, 0, res);
29 }
30}
31
32int sock_diag_check_cookie(struct sock *sk, const __u32 *cookie)
33{
34 u64 res;
35
36 if (cookie[0] == INET_DIAG_NOCOOKIE && cookie[1] == INET_DIAG_NOCOOKIE)
37 return 0;
38
39 res = sock_gen_cookie(sk);
40 if ((u32)res != cookie[0] || (u32)(res >> 32) != cookie[1])
41 return -ESTALE;
42
43 return 0;
44}
45EXPORT_SYMBOL_GPL(sock_diag_check_cookie);
46
47void sock_diag_save_cookie(struct sock *sk, __u32 *cookie)
48{
49 u64 res = sock_gen_cookie(sk);
50
51 cookie[0] = (u32)res;
52 cookie[1] = (u32)(res >> 32);
53}
54EXPORT_SYMBOL_GPL(sock_diag_save_cookie);
55
56int sock_diag_put_meminfo(struct sock *sk, struct sk_buff *skb, int attrtype)
57{
58 u32 mem[SK_MEMINFO_VARS];
59
60 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
61 mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf;
62 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
63 mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf;
64 mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
65 mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued;
66 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
67 mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len;
68
69 return nla_put(skb, attrtype, sizeof(mem), &mem);
70}
71EXPORT_SYMBOL_GPL(sock_diag_put_meminfo);
72
73int sock_diag_put_filterinfo(bool may_report_filterinfo, struct sock *sk,
74 struct sk_buff *skb, int attrtype)
75{
76 struct sock_fprog_kern *fprog;
77 struct sk_filter *filter;
78 struct nlattr *attr;
79 unsigned int flen;
80 int err = 0;
81
82 if (!may_report_filterinfo) {
83 nla_reserve(skb, attrtype, 0);
84 return 0;
85 }
86
87 rcu_read_lock();
88 filter = rcu_dereference(sk->sk_filter);
89 if (!filter)
90 goto out;
91
92 fprog = filter->prog->orig_prog;
93 flen = bpf_classic_proglen(fprog);
94
95 attr = nla_reserve(skb, attrtype, flen);
96 if (attr == NULL) {
97 err = -EMSGSIZE;
98 goto out;
99 }
100
101 memcpy(nla_data(attr), fprog->filter, flen);
102out:
103 rcu_read_unlock();
104 return err;
105}
106EXPORT_SYMBOL(sock_diag_put_filterinfo);
107
108struct broadcast_sk {
109 struct sock *sk;
110 struct work_struct work;
111};
112
113static size_t sock_diag_nlmsg_size(void)
114{
115 return NLMSG_ALIGN(sizeof(struct inet_diag_msg)
116 + nla_total_size(sizeof(u8))
117 + nla_total_size(sizeof(struct tcp_info)));
118}
119
120static void sock_diag_broadcast_destroy_work(struct work_struct *work)
121{
122 struct broadcast_sk *bsk =
123 container_of(work, struct broadcast_sk, work);
124 struct sock *sk = bsk->sk;
125 const struct sock_diag_handler *hndl;
126 struct sk_buff *skb;
127 const enum sknetlink_groups group = sock_diag_destroy_group(sk);
128 int err = -1;
129
130 WARN_ON(group == SKNLGRP_NONE);
131
132 skb = nlmsg_new(sock_diag_nlmsg_size(), GFP_KERNEL);
133 if (!skb)
134 goto out;
135
136 mutex_lock(&sock_diag_table_mutex);
137 hndl = sock_diag_handlers[sk->sk_family];
138 if (hndl && hndl->get_info)
139 err = hndl->get_info(skb, sk);
140 mutex_unlock(&sock_diag_table_mutex);
141
142 if (!err)
143 nlmsg_multicast(sock_net(sk)->diag_nlsk, skb, 0, group,
144 GFP_KERNEL);
145 else
146 kfree_skb(skb);
147out:
148 sk_destruct(sk);
149 kfree(bsk);
150}
151
152void sock_diag_broadcast_destroy(struct sock *sk)
153{
154
155 struct broadcast_sk *bsk =
156 kmalloc(sizeof(struct broadcast_sk), GFP_ATOMIC);
157 if (!bsk)
158 return sk_destruct(sk);
159 bsk->sk = sk;
160 INIT_WORK(&bsk->work, sock_diag_broadcast_destroy_work);
161 queue_work(broadcast_wq, &bsk->work);
162}
163
164void sock_diag_register_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh))
165{
166 mutex_lock(&sock_diag_table_mutex);
167 inet_rcv_compat = fn;
168 mutex_unlock(&sock_diag_table_mutex);
169}
170EXPORT_SYMBOL_GPL(sock_diag_register_inet_compat);
171
172void sock_diag_unregister_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh))
173{
174 mutex_lock(&sock_diag_table_mutex);
175 inet_rcv_compat = NULL;
176 mutex_unlock(&sock_diag_table_mutex);
177}
178EXPORT_SYMBOL_GPL(sock_diag_unregister_inet_compat);
179
180int sock_diag_register(const struct sock_diag_handler *hndl)
181{
182 int err = 0;
183
184 if (hndl->family >= AF_MAX)
185 return -EINVAL;
186
187 mutex_lock(&sock_diag_table_mutex);
188 if (sock_diag_handlers[hndl->family])
189 err = -EBUSY;
190 else
191 sock_diag_handlers[hndl->family] = hndl;
192 mutex_unlock(&sock_diag_table_mutex);
193
194 return err;
195}
196EXPORT_SYMBOL_GPL(sock_diag_register);
197
198void sock_diag_unregister(const struct sock_diag_handler *hnld)
199{
200 int family = hnld->family;
201
202 if (family >= AF_MAX)
203 return;
204
205 mutex_lock(&sock_diag_table_mutex);
206 BUG_ON(sock_diag_handlers[family] != hnld);
207 sock_diag_handlers[family] = NULL;
208 mutex_unlock(&sock_diag_table_mutex);
209}
210EXPORT_SYMBOL_GPL(sock_diag_unregister);
211
212static int __sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
213{
214 int err;
215 struct sock_diag_req *req = nlmsg_data(nlh);
216 const struct sock_diag_handler *hndl;
217
218 if (nlmsg_len(nlh) < sizeof(*req))
219 return -EINVAL;
220
221 if (req->sdiag_family >= AF_MAX)
222 return -EINVAL;
223
224 if (sock_diag_handlers[req->sdiag_family] == NULL)
225 request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
226 NETLINK_SOCK_DIAG, req->sdiag_family);
227
228 mutex_lock(&sock_diag_table_mutex);
229 hndl = sock_diag_handlers[req->sdiag_family];
230 if (hndl == NULL)
231 err = -ENOENT;
232 else
233 err = hndl->dump(skb, nlh);
234 mutex_unlock(&sock_diag_table_mutex);
235
236 return err;
237}
238
239static int sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
240{
241 int ret;
242
243 switch (nlh->nlmsg_type) {
244 case TCPDIAG_GETSOCK:
245 case DCCPDIAG_GETSOCK:
246 if (inet_rcv_compat == NULL)
247 request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
248 NETLINK_SOCK_DIAG, AF_INET);
249
250 mutex_lock(&sock_diag_table_mutex);
251 if (inet_rcv_compat != NULL)
252 ret = inet_rcv_compat(skb, nlh);
253 else
254 ret = -EOPNOTSUPP;
255 mutex_unlock(&sock_diag_table_mutex);
256
257 return ret;
258 case SOCK_DIAG_BY_FAMILY:
259 return __sock_diag_rcv_msg(skb, nlh);
260 default:
261 return -EINVAL;
262 }
263}
264
265static DEFINE_MUTEX(sock_diag_mutex);
266
267static void sock_diag_rcv(struct sk_buff *skb)
268{
269 mutex_lock(&sock_diag_mutex);
270 netlink_rcv_skb(skb, &sock_diag_rcv_msg);
271 mutex_unlock(&sock_diag_mutex);
272}
273
274static int sock_diag_bind(struct net *net, int group)
275{
276 switch (group) {
277 case SKNLGRP_INET_TCP_DESTROY:
278 case SKNLGRP_INET_UDP_DESTROY:
279 if (!sock_diag_handlers[AF_INET])
280 request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
281 NETLINK_SOCK_DIAG, AF_INET);
282 break;
283 case SKNLGRP_INET6_TCP_DESTROY:
284 case SKNLGRP_INET6_UDP_DESTROY:
285 if (!sock_diag_handlers[AF_INET6])
286 request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
287 NETLINK_SOCK_DIAG, AF_INET);
288 break;
289 }
290 return 0;
291}
292
293static int __net_init diag_net_init(struct net *net)
294{
295 struct netlink_kernel_cfg cfg = {
296 .groups = SKNLGRP_MAX,
297 .input = sock_diag_rcv,
298 .bind = sock_diag_bind,
299 .flags = NL_CFG_F_NONROOT_RECV,
300 };
301
302 net->diag_nlsk = netlink_kernel_create(net, NETLINK_SOCK_DIAG, &cfg);
303 return net->diag_nlsk == NULL ? -ENOMEM : 0;
304}
305
306static void __net_exit diag_net_exit(struct net *net)
307{
308 netlink_kernel_release(net->diag_nlsk);
309 net->diag_nlsk = NULL;
310}
311
312static struct pernet_operations diag_net_ops = {
313 .init = diag_net_init,
314 .exit = diag_net_exit,
315};
316
317static int __init sock_diag_init(void)
318{
319 broadcast_wq = alloc_workqueue("sock_diag_events", 0, 0);
320 BUG_ON(!broadcast_wq);
321 return register_pernet_subsys(&diag_net_ops);
322}
323
324static void __exit sock_diag_exit(void)
325{
326 unregister_pernet_subsys(&diag_net_ops);
327 destroy_workqueue(broadcast_wq);
328}
329
330module_init(sock_diag_init);
331module_exit(sock_diag_exit);
332MODULE_LICENSE("GPL");
333MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_SOCK_DIAG);
334
