Commit | Line | Data |
---|---|---|
b6191aee PG |
1 | /* License: GPL */ |
2 | ||
b6459415 | 3 | #include <linux/filter.h> |
8ef874bf PE |
4 | #include <linux/mutex.h> |
5 | #include <linux/socket.h> | |
6 | #include <linux/skbuff.h> | |
7 | #include <net/netlink.h> | |
8 | #include <net/net_namespace.h> | |
9 | #include <linux/module.h> | |
5d2e5f27 | 10 | #include <net/sock.h> |
eb4cb008 CG |
11 | #include <linux/kernel.h> |
12 | #include <linux/tcp.h> | |
13 | #include <linux/workqueue.h> | |
66b51b0a | 14 | #include <linux/nospec.h> |
92acdc58 | 15 | #include <linux/cookie.h> |
8ef874bf PE |
16 | #include <linux/inet_diag.h> |
17 | #include <linux/sock_diag.h> | |
18 | ||
1d55a697 | 19 | static const struct sock_diag_handler __rcu *sock_diag_handlers[AF_MAX]; |
86e8921d | 20 | |
b4cb4a13 | 21 | static const struct sock_diag_inet_compat __rcu *inet_rcv_compat; |
86e8921d | 22 | |
eb4cb008 | 23 | static struct workqueue_struct *broadcast_wq; |
8ef874bf | 24 | |
92acdc58 DB |
25 | DEFINE_COOKIE(sock_cookie); |
26 | ||
27 | u64 __sock_gen_cookie(struct sock *sk) | |
f65c1b53 | 28 | { |
4ebf802c | 29 | u64 res = atomic64_read(&sk->sk_cookie); |
33cf7c90 | 30 | |
4ebf802c ED |
31 | if (!res) { |
32 | u64 new = gen_cookie_next(&sock_cookie); | |
33 | ||
32634819 ED |
34 | atomic64_cmpxchg(&sk->sk_cookie, res, new); |
35 | ||
36 | /* Another thread might have changed sk_cookie before us. */ | |
37 | res = atomic64_read(&sk->sk_cookie); | |
33cf7c90 | 38 | } |
4ebf802c | 39 | return res; |
33cf7c90 ED |
40 | } |
41 | ||
42 | int sock_diag_check_cookie(struct sock *sk, const __u32 *cookie) | |
43 | { | |
44 | u64 res; | |
45 | ||
46 | if (cookie[0] == INET_DIAG_NOCOOKIE && cookie[1] == INET_DIAG_NOCOOKIE) | |
f65c1b53 | 47 | return 0; |
33cf7c90 ED |
48 | |
49 | res = sock_gen_cookie(sk); | |
50 | if ((u32)res != cookie[0] || (u32)(res >> 32) != cookie[1]) | |
51 | return -ESTALE; | |
52 | ||
53 | return 0; | |
f65c1b53 PE |
54 | } |
55 | EXPORT_SYMBOL_GPL(sock_diag_check_cookie); | |
56 | ||
33cf7c90 | 57 | void sock_diag_save_cookie(struct sock *sk, __u32 *cookie) |
f65c1b53 | 58 | { |
33cf7c90 ED |
59 | u64 res = sock_gen_cookie(sk); |
60 | ||
61 | cookie[0] = (u32)res; | |
62 | cookie[1] = (u32)(res >> 32); | |
f65c1b53 PE |
63 | } |
64 | EXPORT_SYMBOL_GPL(sock_diag_save_cookie); | |
65 | ||
5d2e5f27 PE |
66 | int sock_diag_put_meminfo(struct sock *sk, struct sk_buff *skb, int attrtype) |
67 | { | |
7b46866d | 68 | u32 mem[SK_MEMINFO_VARS]; |
5d2e5f27 | 69 | |
a2d133b1 | 70 | sk_get_meminfo(sk, mem); |
5d2e5f27 | 71 | |
7b46866d | 72 | return nla_put(skb, attrtype, sizeof(mem), &mem); |
5d2e5f27 PE |
73 | } |
74 | EXPORT_SYMBOL_GPL(sock_diag_put_meminfo); | |
75 | ||
a53b72c8 | 76 | int sock_diag_put_filterinfo(bool may_report_filterinfo, struct sock *sk, |
e8d9612c ND |
77 | struct sk_buff *skb, int attrtype) |
78 | { | |
a3ea269b | 79 | struct sock_fprog_kern *fprog; |
e8d9612c | 80 | struct sk_filter *filter; |
a3ea269b DB |
81 | struct nlattr *attr; |
82 | unsigned int flen; | |
e8d9612c ND |
83 | int err = 0; |
84 | ||
a53b72c8 | 85 | if (!may_report_filterinfo) { |
e8d9612c ND |
86 | nla_reserve(skb, attrtype, 0); |
87 | return 0; | |
88 | } | |
89 | ||
90 | rcu_read_lock(); | |
e8d9612c | 91 | filter = rcu_dereference(sk->sk_filter); |
a3ea269b DB |
92 | if (!filter) |
93 | goto out; | |
e8d9612c | 94 | |
7ae457c1 | 95 | fprog = filter->prog->orig_prog; |
b382c086 DB |
96 | if (!fprog) |
97 | goto out; | |
98 | ||
009937e7 | 99 | flen = bpf_classic_proglen(fprog); |
a3ea269b DB |
100 | |
101 | attr = nla_reserve(skb, attrtype, flen); | |
e8d9612c ND |
102 | if (attr == NULL) { |
103 | err = -EMSGSIZE; | |
104 | goto out; | |
105 | } | |
106 | ||
a3ea269b | 107 | memcpy(nla_data(attr), fprog->filter, flen); |
e8d9612c ND |
108 | out: |
109 | rcu_read_unlock(); | |
110 | return err; | |
111 | } | |
112 | EXPORT_SYMBOL(sock_diag_put_filterinfo); | |
113 | ||
eb4cb008 CG |
114 | struct broadcast_sk { |
115 | struct sock *sk; | |
116 | struct work_struct work; | |
117 | }; | |
118 | ||
119 | static size_t sock_diag_nlmsg_size(void) | |
120 | { | |
121 | return NLMSG_ALIGN(sizeof(struct inet_diag_msg) | |
122 | + nla_total_size(sizeof(u8)) /* INET_DIAG_PROTOCOL */ | |
6ed46d12 | 123 | + nla_total_size_64bit(sizeof(struct tcp_info))); /* INET_DIAG_INFO */ |
eb4cb008 CG |
124 | } |
125 | ||
1d55a697 ED |
126 | static const struct sock_diag_handler *sock_diag_lock_handler(int family) |
127 | { | |
128 | const struct sock_diag_handler *handler; | |
129 | ||
130 | rcu_read_lock(); | |
131 | handler = rcu_dereference(sock_diag_handlers[family]); | |
132 | if (handler && !try_module_get(handler->owner)) | |
133 | handler = NULL; | |
134 | rcu_read_unlock(); | |
135 | ||
136 | return handler; | |
137 | } | |
138 | ||
139 | static void sock_diag_unlock_handler(const struct sock_diag_handler *handler) | |
140 | { | |
141 | module_put(handler->owner); | |
142 | } | |
143 | ||
eb4cb008 CG |
144 | static void sock_diag_broadcast_destroy_work(struct work_struct *work) |
145 | { | |
146 | struct broadcast_sk *bsk = | |
147 | container_of(work, struct broadcast_sk, work); | |
148 | struct sock *sk = bsk->sk; | |
149 | const struct sock_diag_handler *hndl; | |
150 | struct sk_buff *skb; | |
151 | const enum sknetlink_groups group = sock_diag_destroy_group(sk); | |
152 | int err = -1; | |
153 | ||
154 | WARN_ON(group == SKNLGRP_NONE); | |
155 | ||
156 | skb = nlmsg_new(sock_diag_nlmsg_size(), GFP_KERNEL); | |
157 | if (!skb) | |
158 | goto out; | |
159 | ||
1d55a697 ED |
160 | hndl = sock_diag_lock_handler(sk->sk_family); |
161 | if (hndl) { | |
162 | if (hndl->get_info) | |
163 | err = hndl->get_info(skb, sk); | |
164 | sock_diag_unlock_handler(hndl); | |
165 | } | |
eb4cb008 CG |
166 | if (!err) |
167 | nlmsg_multicast(sock_net(sk)->diag_nlsk, skb, 0, group, | |
168 | GFP_KERNEL); | |
169 | else | |
170 | kfree_skb(skb); | |
171 | out: | |
172 | sk_destruct(sk); | |
173 | kfree(bsk); | |
174 | } | |
175 | ||
176 | void sock_diag_broadcast_destroy(struct sock *sk) | |
177 | { | |
178 | /* Note, this function is often called from an interrupt context. */ | |
179 | struct broadcast_sk *bsk = | |
180 | kmalloc(sizeof(struct broadcast_sk), GFP_ATOMIC); | |
181 | if (!bsk) | |
182 | return sk_destruct(sk); | |
183 | bsk->sk = sk; | |
184 | INIT_WORK(&bsk->work, sock_diag_broadcast_destroy_work); | |
185 | queue_work(broadcast_wq, &bsk->work); | |
186 | } | |
187 | ||
86e8921d | 188 | void sock_diag_register_inet_compat(const struct sock_diag_inet_compat *ptr) |
8ef874bf | 189 | { |
b4cb4a13 | 190 | xchg(&inet_rcv_compat, RCU_INITIALIZER(ptr)); |
8ef874bf PE |
191 | } |
192 | EXPORT_SYMBOL_GPL(sock_diag_register_inet_compat); | |
193 | ||
86e8921d | 194 | void sock_diag_unregister_inet_compat(const struct sock_diag_inet_compat *ptr) |
8ef874bf | 195 | { |
86e8921d ED |
196 | const struct sock_diag_inet_compat *old; |
197 | ||
b4cb4a13 | 198 | old = unrcu_pointer(xchg(&inet_rcv_compat, NULL)); |
86e8921d | 199 | WARN_ON_ONCE(old != ptr); |
8ef874bf PE |
200 | } |
201 | EXPORT_SYMBOL_GPL(sock_diag_unregister_inet_compat); | |
202 | ||
8dcf01fc | 203 | int sock_diag_register(const struct sock_diag_handler *hndl) |
8ef874bf | 204 | { |
1d55a697 | 205 | int family = hndl->family; |
8ef874bf | 206 | |
1d55a697 | 207 | if (family >= AF_MAX) |
8ef874bf PE |
208 | return -EINVAL; |
209 | ||
1d55a697 ED |
210 | return !cmpxchg((const struct sock_diag_handler **) |
211 | &sock_diag_handlers[family], | |
212 | NULL, hndl) ? 0 : -EBUSY; | |
8ef874bf PE |
213 | } |
214 | EXPORT_SYMBOL_GPL(sock_diag_register); | |
215 | ||
1d55a697 | 216 | void sock_diag_unregister(const struct sock_diag_handler *hndl) |
8ef874bf | 217 | { |
1d55a697 | 218 | int family = hndl->family; |
8ef874bf | 219 | |
6f8e4ad0 | 220 | if (family >= AF_MAX) |
8ef874bf PE |
221 | return; |
222 | ||
1d55a697 ED |
223 | xchg((const struct sock_diag_handler **)&sock_diag_handlers[family], |
224 | NULL); | |
8ef874bf PE |
225 | } |
226 | EXPORT_SYMBOL_GPL(sock_diag_unregister); | |
227 | ||
64be0aed | 228 | static int __sock_diag_cmd(struct sk_buff *skb, struct nlmsghdr *nlh) |
8ef874bf PE |
229 | { |
230 | int err; | |
7b46866d | 231 | struct sock_diag_req *req = nlmsg_data(nlh); |
8dcf01fc | 232 | const struct sock_diag_handler *hndl; |
8ef874bf PE |
233 | |
234 | if (nlmsg_len(nlh) < sizeof(*req)) | |
235 | return -EINVAL; | |
236 | ||
6e601a53 MK |
237 | if (req->sdiag_family >= AF_MAX) |
238 | return -EINVAL; | |
66b51b0a | 239 | req->sdiag_family = array_index_nospec(req->sdiag_family, AF_MAX); |
6e601a53 | 240 | |
1d55a697 | 241 | if (!rcu_access_pointer(sock_diag_handlers[req->sdiag_family])) |
bf2ae2e4 | 242 | sock_load_diag_module(req->sdiag_family, 0); |
8e904550 | 243 | |
1d55a697 | 244 | hndl = sock_diag_lock_handler(req->sdiag_family); |
8ef874bf | 245 | if (hndl == NULL) |
1d55a697 ED |
246 | return -ENOENT; |
247 | ||
248 | if (nlh->nlmsg_type == SOCK_DIAG_BY_FAMILY) | |
8ef874bf | 249 | err = hndl->dump(skb, nlh); |
64be0aed LC |
250 | else if (nlh->nlmsg_type == SOCK_DESTROY && hndl->destroy) |
251 | err = hndl->destroy(skb, nlh); | |
252 | else | |
253 | err = -EOPNOTSUPP; | |
1d55a697 | 254 | sock_diag_unlock_handler(hndl); |
8ef874bf PE |
255 | |
256 | return err; | |
257 | } | |
258 | ||
2d4bc933 JB |
259 | static int sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, |
260 | struct netlink_ext_ack *extack) | |
8ef874bf | 261 | { |
86e8921d | 262 | const struct sock_diag_inet_compat *ptr; |
8ef874bf PE |
263 | int ret; |
264 | ||
265 | switch (nlh->nlmsg_type) { | |
266 | case TCPDIAG_GETSOCK: | |
267 | case DCCPDIAG_GETSOCK: | |
86e8921d ED |
268 | |
269 | if (!rcu_access_pointer(inet_rcv_compat)) | |
bf2ae2e4 | 270 | sock_load_diag_module(AF_INET, 0); |
8ef874bf | 271 | |
86e8921d ED |
272 | rcu_read_lock(); |
273 | ptr = rcu_dereference(inet_rcv_compat); | |
274 | if (ptr && !try_module_get(ptr->owner)) | |
275 | ptr = NULL; | |
276 | rcu_read_unlock(); | |
277 | ||
278 | ret = -EOPNOTSUPP; | |
279 | if (ptr) { | |
280 | ret = ptr->fn(skb, nlh); | |
281 | module_put(ptr->owner); | |
282 | } | |
8ef874bf PE |
283 | |
284 | return ret; | |
285 | case SOCK_DIAG_BY_FAMILY: | |
64be0aed LC |
286 | case SOCK_DESTROY: |
287 | return __sock_diag_cmd(skb, nlh); | |
8ef874bf PE |
288 | default: |
289 | return -EINVAL; | |
290 | } | |
291 | } | |
292 | ||
8ef874bf PE |
293 | static void sock_diag_rcv(struct sk_buff *skb) |
294 | { | |
8ef874bf | 295 | netlink_rcv_skb(skb, &sock_diag_rcv_msg); |
8ef874bf PE |
296 | } |
297 | ||
eb4cb008 CG |
298 | static int sock_diag_bind(struct net *net, int group) |
299 | { | |
300 | switch (group) { | |
301 | case SKNLGRP_INET_TCP_DESTROY: | |
302 | case SKNLGRP_INET_UDP_DESTROY: | |
1d55a697 | 303 | if (!rcu_access_pointer(sock_diag_handlers[AF_INET])) |
bf2ae2e4 | 304 | sock_load_diag_module(AF_INET, 0); |
eb4cb008 CG |
305 | break; |
306 | case SKNLGRP_INET6_TCP_DESTROY: | |
307 | case SKNLGRP_INET6_UDP_DESTROY: | |
1d55a697 | 308 | if (!rcu_access_pointer(sock_diag_handlers[AF_INET6])) |
bf2ae2e4 | 309 | sock_load_diag_module(AF_INET6, 0); |
eb4cb008 CG |
310 | break; |
311 | } | |
312 | return 0; | |
313 | } | |
314 | ||
64be0aed LC |
315 | int sock_diag_destroy(struct sock *sk, int err) |
316 | { | |
317 | if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN)) | |
318 | return -EPERM; | |
319 | ||
320 | if (!sk->sk_prot->diag_destroy) | |
321 | return -EOPNOTSUPP; | |
322 | ||
323 | return sk->sk_prot->diag_destroy(sk, err); | |
324 | } | |
325 | EXPORT_SYMBOL_GPL(sock_diag_destroy); | |
326 | ||
51d7cccf | 327 | static int __net_init diag_net_init(struct net *net) |
8ef874bf | 328 | { |
a31f2d17 | 329 | struct netlink_kernel_cfg cfg = { |
eb4cb008 | 330 | .groups = SKNLGRP_MAX, |
a31f2d17 | 331 | .input = sock_diag_rcv, |
eb4cb008 CG |
332 | .bind = sock_diag_bind, |
333 | .flags = NL_CFG_F_NONROOT_RECV, | |
a31f2d17 PNA |
334 | }; |
335 | ||
9f00d977 | 336 | net->diag_nlsk = netlink_kernel_create(net, NETLINK_SOCK_DIAG, &cfg); |
51d7cccf AV |
337 | return net->diag_nlsk == NULL ? -ENOMEM : 0; |
338 | } | |
339 | ||
340 | static void __net_exit diag_net_exit(struct net *net) | |
341 | { | |
342 | netlink_kernel_release(net->diag_nlsk); | |
343 | net->diag_nlsk = NULL; | |
344 | } | |
345 | ||
346 | static struct pernet_operations diag_net_ops = { | |
347 | .init = diag_net_init, | |
348 | .exit = diag_net_exit, | |
349 | }; | |
350 | ||
351 | static int __init sock_diag_init(void) | |
352 | { | |
eb4cb008 CG |
353 | broadcast_wq = alloc_workqueue("sock_diag_events", 0, 0); |
354 | BUG_ON(!broadcast_wq); | |
51d7cccf | 355 | return register_pernet_subsys(&diag_net_ops); |
8ef874bf | 356 | } |
b6191aee | 357 | device_initcall(sock_diag_init); |