1
2
3#include <linux/mutex.h>
4#include <linux/socket.h>
5#include <linux/skbuff.h>
6#include <net/netlink.h>
7#include <net/net_namespace.h>
8#include <linux/module.h>
9#include <net/sock.h>
10#include <linux/kernel.h>
11#include <linux/tcp.h>
12#include <linux/workqueue.h>
13
14#include <linux/inet_diag.h>
15#include <linux/sock_diag.h>
16
17static const struct sock_diag_handler *sock_diag_handlers[AF_MAX];
18static int (*inet_rcv_compat)(struct sk_buff *skb, struct nlmsghdr *nlh);
19static DEFINE_MUTEX(sock_diag_table_mutex);
20static struct workqueue_struct *broadcast_wq;
21
22static u64 sock_gen_cookie(struct sock *sk)
23{
24 while (1) {
25 u64 res = atomic64_read(&sk->sk_cookie);
26
27 if (res)
28 return res;
29 res = atomic64_inc_return(&sock_net(sk)->cookie_gen);
30 atomic64_cmpxchg(&sk->sk_cookie, 0, res);
31 }
32}
33
34int sock_diag_check_cookie(struct sock *sk, const __u32 *cookie)
35{
36 u64 res;
37
38 if (cookie[0] == INET_DIAG_NOCOOKIE && cookie[1] == INET_DIAG_NOCOOKIE)
39 return 0;
40
41 res = sock_gen_cookie(sk);
42 if ((u32)res != cookie[0] || (u32)(res >> 32) != cookie[1])
43 return -ESTALE;
44
45 return 0;
46}
47EXPORT_SYMBOL_GPL(sock_diag_check_cookie);
48
49void sock_diag_save_cookie(struct sock *sk, __u32 *cookie)
50{
51 u64 res = sock_gen_cookie(sk);
52
53 cookie[0] = (u32)res;
54 cookie[1] = (u32)(res >> 32);
55}
56EXPORT_SYMBOL_GPL(sock_diag_save_cookie);
57
58int sock_diag_put_meminfo(struct sock *sk, struct sk_buff *skb, int attrtype)
59{
60 u32 mem[SK_MEMINFO_VARS];
61
62 mem[SK_MEMINFO_RMEM_ALLOC] = sk_rmem_alloc_get(sk);
63 mem[SK_MEMINFO_RCVBUF] = sk->sk_rcvbuf;
64 mem[SK_MEMINFO_WMEM_ALLOC] = sk_wmem_alloc_get(sk);
65 mem[SK_MEMINFO_SNDBUF] = sk->sk_sndbuf;
66 mem[SK_MEMINFO_FWD_ALLOC] = sk->sk_forward_alloc;
67 mem[SK_MEMINFO_WMEM_QUEUED] = sk->sk_wmem_queued;
68 mem[SK_MEMINFO_OPTMEM] = atomic_read(&sk->sk_omem_alloc);
69 mem[SK_MEMINFO_BACKLOG] = sk->sk_backlog.len;
70
71 return nla_put(skb, attrtype, sizeof(mem), &mem);
72}
73EXPORT_SYMBOL_GPL(sock_diag_put_meminfo);
74
75int sock_diag_put_filterinfo(bool may_report_filterinfo, struct sock *sk,
76 struct sk_buff *skb, int attrtype)
77{
78 struct sock_fprog_kern *fprog;
79 struct sk_filter *filter;
80 struct nlattr *attr;
81 unsigned int flen;
82 int err = 0;
83
84 if (!may_report_filterinfo) {
85 nla_reserve(skb, attrtype, 0);
86 return 0;
87 }
88
89 rcu_read_lock();
90 filter = rcu_dereference(sk->sk_filter);
91 if (!filter)
92 goto out;
93
94 fprog = filter->prog->orig_prog;
95 if (!fprog)
96 goto out;
97
98 flen = bpf_classic_proglen(fprog);
99
100 attr = nla_reserve(skb, attrtype, flen);
101 if (attr == NULL) {
102 err = -EMSGSIZE;
103 goto out;
104 }
105
106 memcpy(nla_data(attr), fprog->filter, flen);
107out:
108 rcu_read_unlock();
109 return err;
110}
111EXPORT_SYMBOL(sock_diag_put_filterinfo);
112
113struct broadcast_sk {
114 struct sock *sk;
115 struct work_struct work;
116};
117
118static size_t sock_diag_nlmsg_size(void)
119{
120 return NLMSG_ALIGN(sizeof(struct inet_diag_msg)
121 + nla_total_size(sizeof(u8))
122 + nla_total_size(sizeof(struct tcp_info)));
123}
124
125static void sock_diag_broadcast_destroy_work(struct work_struct *work)
126{
127 struct broadcast_sk *bsk =
128 container_of(work, struct broadcast_sk, work);
129 struct sock *sk = bsk->sk;
130 const struct sock_diag_handler *hndl;
131 struct sk_buff *skb;
132 const enum sknetlink_groups group = sock_diag_destroy_group(sk);
133 int err = -1;
134
135 WARN_ON(group == SKNLGRP_NONE);
136
137 skb = nlmsg_new(sock_diag_nlmsg_size(), GFP_KERNEL);
138 if (!skb)
139 goto out;
140
141 mutex_lock(&sock_diag_table_mutex);
142 hndl = sock_diag_handlers[sk->sk_family];
143 if (hndl && hndl->get_info)
144 err = hndl->get_info(skb, sk);
145 mutex_unlock(&sock_diag_table_mutex);
146
147 if (!err)
148 nlmsg_multicast(sock_net(sk)->diag_nlsk, skb, 0, group,
149 GFP_KERNEL);
150 else
151 kfree_skb(skb);
152out:
153 sk_destruct(sk);
154 kfree(bsk);
155}
156
157void sock_diag_broadcast_destroy(struct sock *sk)
158{
159
160 struct broadcast_sk *bsk =
161 kmalloc(sizeof(struct broadcast_sk), GFP_ATOMIC);
162 if (!bsk)
163 return sk_destruct(sk);
164 bsk->sk = sk;
165 INIT_WORK(&bsk->work, sock_diag_broadcast_destroy_work);
166 queue_work(broadcast_wq, &bsk->work);
167}
168
169void sock_diag_register_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh))
170{
171 mutex_lock(&sock_diag_table_mutex);
172 inet_rcv_compat = fn;
173 mutex_unlock(&sock_diag_table_mutex);
174}
175EXPORT_SYMBOL_GPL(sock_diag_register_inet_compat);
176
177void sock_diag_unregister_inet_compat(int (*fn)(struct sk_buff *skb, struct nlmsghdr *nlh))
178{
179 mutex_lock(&sock_diag_table_mutex);
180 inet_rcv_compat = NULL;
181 mutex_unlock(&sock_diag_table_mutex);
182}
183EXPORT_SYMBOL_GPL(sock_diag_unregister_inet_compat);
184
185int sock_diag_register(const struct sock_diag_handler *hndl)
186{
187 int err = 0;
188
189 if (hndl->family >= AF_MAX)
190 return -EINVAL;
191
192 mutex_lock(&sock_diag_table_mutex);
193 if (sock_diag_handlers[hndl->family])
194 err = -EBUSY;
195 else
196 sock_diag_handlers[hndl->family] = hndl;
197 mutex_unlock(&sock_diag_table_mutex);
198
199 return err;
200}
201EXPORT_SYMBOL_GPL(sock_diag_register);
202
203void sock_diag_unregister(const struct sock_diag_handler *hnld)
204{
205 int family = hnld->family;
206
207 if (family >= AF_MAX)
208 return;
209
210 mutex_lock(&sock_diag_table_mutex);
211 BUG_ON(sock_diag_handlers[family] != hnld);
212 sock_diag_handlers[family] = NULL;
213 mutex_unlock(&sock_diag_table_mutex);
214}
215EXPORT_SYMBOL_GPL(sock_diag_unregister);
216
217static int __sock_diag_cmd(struct sk_buff *skb, struct nlmsghdr *nlh)
218{
219 int err;
220 struct sock_diag_req *req = nlmsg_data(nlh);
221 const struct sock_diag_handler *hndl;
222
223 if (nlmsg_len(nlh) < sizeof(*req))
224 return -EINVAL;
225
226 if (req->sdiag_family >= AF_MAX)
227 return -EINVAL;
228
229 if (sock_diag_handlers[req->sdiag_family] == NULL)
230 request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
231 NETLINK_SOCK_DIAG, req->sdiag_family);
232
233 mutex_lock(&sock_diag_table_mutex);
234 hndl = sock_diag_handlers[req->sdiag_family];
235 if (hndl == NULL)
236 err = -ENOENT;
237 else if (nlh->nlmsg_type == SOCK_DIAG_BY_FAMILY)
238 err = hndl->dump(skb, nlh);
239 else if (nlh->nlmsg_type == SOCK_DESTROY && hndl->destroy)
240 err = hndl->destroy(skb, nlh);
241 else
242 err = -EOPNOTSUPP;
243 mutex_unlock(&sock_diag_table_mutex);
244
245 return err;
246}
247
248static int sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
249{
250 int ret;
251
252 switch (nlh->nlmsg_type) {
253 case TCPDIAG_GETSOCK:
254 case DCCPDIAG_GETSOCK:
255 if (inet_rcv_compat == NULL)
256 request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
257 NETLINK_SOCK_DIAG, AF_INET);
258
259 mutex_lock(&sock_diag_table_mutex);
260 if (inet_rcv_compat != NULL)
261 ret = inet_rcv_compat(skb, nlh);
262 else
263 ret = -EOPNOTSUPP;
264 mutex_unlock(&sock_diag_table_mutex);
265
266 return ret;
267 case SOCK_DIAG_BY_FAMILY:
268 case SOCK_DESTROY:
269 return __sock_diag_cmd(skb, nlh);
270 default:
271 return -EINVAL;
272 }
273}
274
275static DEFINE_MUTEX(sock_diag_mutex);
276
277static void sock_diag_rcv(struct sk_buff *skb)
278{
279 mutex_lock(&sock_diag_mutex);
280 netlink_rcv_skb(skb, &sock_diag_rcv_msg);
281 mutex_unlock(&sock_diag_mutex);
282}
283
284static int sock_diag_bind(struct net *net, int group)
285{
286 switch (group) {
287 case SKNLGRP_INET_TCP_DESTROY:
288 case SKNLGRP_INET_UDP_DESTROY:
289 if (!sock_diag_handlers[AF_INET])
290 request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
291 NETLINK_SOCK_DIAG, AF_INET);
292 break;
293 case SKNLGRP_INET6_TCP_DESTROY:
294 case SKNLGRP_INET6_UDP_DESTROY:
295 if (!sock_diag_handlers[AF_INET6])
296 request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
297 NETLINK_SOCK_DIAG, AF_INET);
298 break;
299 }
300 return 0;
301}
302
303int sock_diag_destroy(struct sock *sk, int err)
304{
305 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
306 return -EPERM;
307
308 if (!sk->sk_prot->diag_destroy)
309 return -EOPNOTSUPP;
310
311 return sk->sk_prot->diag_destroy(sk, err);
312}
313EXPORT_SYMBOL_GPL(sock_diag_destroy);
314
315static int __net_init diag_net_init(struct net *net)
316{
317 struct netlink_kernel_cfg cfg = {
318 .groups = SKNLGRP_MAX,
319 .input = sock_diag_rcv,
320 .bind = sock_diag_bind,
321 .flags = NL_CFG_F_NONROOT_RECV,
322 };
323
324 net->diag_nlsk = netlink_kernel_create(net, NETLINK_SOCK_DIAG, &cfg);
325 return net->diag_nlsk == NULL ? -ENOMEM : 0;
326}
327
328static void __net_exit diag_net_exit(struct net *net)
329{
330 netlink_kernel_release(net->diag_nlsk);
331 net->diag_nlsk = NULL;
332}
333
334static struct pernet_operations diag_net_ops = {
335 .init = diag_net_init,
336 .exit = diag_net_exit,
337};
338
339static int __init sock_diag_init(void)
340{
341 broadcast_wq = alloc_workqueue("sock_diag_events", 0, 0);
342 BUG_ON(!broadcast_wq);
343 return register_pernet_subsys(&diag_net_ops);
344}
345device_initcall(sock_diag_init);
346
