blob: b1e29e18d1d60cb5c87c884652f547c083ba81cd [file] [log] [blame]
Paul Gortmakerb6191ae2015-10-07 17:27:43 -04001/* License: GPL */
2
Jakub Kicinskib6459412021-12-28 16:49:13 -08003#include <linux/filter.h>
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +00004#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>
Pavel Emelyanov5d2e5f272011-12-30 00:53:13 +000010#include <net/sock.h>
Craig Gallekeb4cb002015-06-15 11:26:18 -040011#include <linux/kernel.h>
12#include <linux/tcp.h>
13#include <linux/workqueue.h>
Jeremy Cline66b51b02018-08-13 22:23:13 +000014#include <linux/nospec.h>
Daniel Borkmann92acdc52020-09-30 17:18:16 +020015#include <linux/cookie.h>
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +000016#include <linux/inet_diag.h>
17#include <linux/sock_diag.h>
18
Shan Wei8dcf01f2012-04-24 18:21:07 +000019static const struct sock_diag_handler *sock_diag_handlers[AF_MAX];
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +000020static int (*inet_rcv_compat)(struct sk_buff *skb, struct nlmsghdr *nlh);
21static DEFINE_MUTEX(sock_diag_table_mutex);
Craig Gallekeb4cb002015-06-15 11:26:18 -040022static struct workqueue_struct *broadcast_wq;
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +000023
Daniel Borkmann92acdc52020-09-30 17:18:16 +020024DEFINE_COOKIE(sock_cookie);
25
26u64 __sock_gen_cookie(struct sock *sk)
Pavel Emelyanovf65c1b52011-12-15 02:43:44 +000027{
Eric Dumazet4ebf8022022-11-15 09:11:01 +000028 u64 res = atomic64_read(&sk->sk_cookie);
Eric Dumazet33cf7c92015-03-11 18:53:14 -070029
Eric Dumazet4ebf8022022-11-15 09:11:01 +000030 if (!res) {
31 u64 new = gen_cookie_next(&sock_cookie);
32
Eric Dumazet32634812022-11-18 04:38:43 +000033 atomic64_cmpxchg(&sk->sk_cookie, res, new);
34
35 /* Another thread might have changed sk_cookie before us. */
36 res = atomic64_read(&sk->sk_cookie);
Eric Dumazet33cf7c92015-03-11 18:53:14 -070037 }
Eric Dumazet4ebf8022022-11-15 09:11:01 +000038 return res;
Eric Dumazet33cf7c92015-03-11 18:53:14 -070039}
40
41int sock_diag_check_cookie(struct sock *sk, const __u32 *cookie)
42{
43 u64 res;
44
45 if (cookie[0] == INET_DIAG_NOCOOKIE && cookie[1] == INET_DIAG_NOCOOKIE)
Pavel Emelyanovf65c1b52011-12-15 02:43:44 +000046 return 0;
Eric Dumazet33cf7c92015-03-11 18:53:14 -070047
48 res = sock_gen_cookie(sk);
49 if ((u32)res != cookie[0] || (u32)(res >> 32) != cookie[1])
50 return -ESTALE;
51
52 return 0;
Pavel Emelyanovf65c1b52011-12-15 02:43:44 +000053}
54EXPORT_SYMBOL_GPL(sock_diag_check_cookie);
55
Eric Dumazet33cf7c92015-03-11 18:53:14 -070056void sock_diag_save_cookie(struct sock *sk, __u32 *cookie)
Pavel Emelyanovf65c1b52011-12-15 02:43:44 +000057{
Eric Dumazet33cf7c92015-03-11 18:53:14 -070058 u64 res = sock_gen_cookie(sk);
59
60 cookie[0] = (u32)res;
61 cookie[1] = (u32)(res >> 32);
Pavel Emelyanovf65c1b52011-12-15 02:43:44 +000062}
63EXPORT_SYMBOL_GPL(sock_diag_save_cookie);
64
Pavel Emelyanov5d2e5f272011-12-30 00:53:13 +000065int sock_diag_put_meminfo(struct sock *sk, struct sk_buff *skb, int attrtype)
66{
Thomas Graf7b468662012-06-26 23:36:11 +000067 u32 mem[SK_MEMINFO_VARS];
Pavel Emelyanov5d2e5f272011-12-30 00:53:13 +000068
Josh Hunta2d133b2017-03-20 15:22:03 -040069 sk_get_meminfo(sk, mem);
Pavel Emelyanov5d2e5f272011-12-30 00:53:13 +000070
Thomas Graf7b468662012-06-26 23:36:11 +000071 return nla_put(skb, attrtype, sizeof(mem), &mem);
Pavel Emelyanov5d2e5f272011-12-30 00:53:13 +000072}
73EXPORT_SYMBOL_GPL(sock_diag_put_meminfo);
74
Eric W. Biedermana53b72c2014-04-23 14:26:25 -070075int sock_diag_put_filterinfo(bool may_report_filterinfo, struct sock *sk,
Nicolas Dichtele8d96122013-04-25 06:53:54 +000076 struct sk_buff *skb, int attrtype)
77{
Daniel Borkmanna3ea2692014-03-28 18:58:19 +010078 struct sock_fprog_kern *fprog;
Nicolas Dichtele8d96122013-04-25 06:53:54 +000079 struct sk_filter *filter;
Daniel Borkmanna3ea2692014-03-28 18:58:19 +010080 struct nlattr *attr;
81 unsigned int flen;
Nicolas Dichtele8d96122013-04-25 06:53:54 +000082 int err = 0;
83
Eric W. Biedermana53b72c2014-04-23 14:26:25 -070084 if (!may_report_filterinfo) {
Nicolas Dichtele8d96122013-04-25 06:53:54 +000085 nla_reserve(skb, attrtype, 0);
86 return 0;
87 }
88
89 rcu_read_lock();
Nicolas Dichtele8d96122013-04-25 06:53:54 +000090 filter = rcu_dereference(sk->sk_filter);
Daniel Borkmanna3ea2692014-03-28 18:58:19 +010091 if (!filter)
92 goto out;
Nicolas Dichtele8d96122013-04-25 06:53:54 +000093
Alexei Starovoitov7ae457c2014-07-30 20:34:16 -070094 fprog = filter->prog->orig_prog;
Daniel Borkmannb382c082015-09-02 14:00:36 +020095 if (!fprog)
96 goto out;
97
Alexei Starovoitov009937e2014-07-30 20:34:13 -070098 flen = bpf_classic_proglen(fprog);
Daniel Borkmanna3ea2692014-03-28 18:58:19 +010099
100 attr = nla_reserve(skb, attrtype, flen);
Nicolas Dichtele8d96122013-04-25 06:53:54 +0000101 if (attr == NULL) {
102 err = -EMSGSIZE;
103 goto out;
104 }
105
Daniel Borkmanna3ea2692014-03-28 18:58:19 +0100106 memcpy(nla_data(attr), fprog->filter, flen);
Nicolas Dichtele8d96122013-04-25 06:53:54 +0000107out:
108 rcu_read_unlock();
109 return err;
110}
111EXPORT_SYMBOL(sock_diag_put_filterinfo);
112
Craig Gallekeb4cb002015-06-15 11:26:18 -0400113struct 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)) /* INET_DIAG_PROTOCOL */
Nicolas Dichtel6ed46d12016-04-26 10:06:14 +0200122 + nla_total_size_64bit(sizeof(struct tcp_info))); /* INET_DIAG_INFO */
Craig Gallekeb4cb002015-06-15 11:26:18 -0400123}
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 /* Note, this function is often called from an interrupt context. */
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
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +0000169void 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
Shan Wei8dcf01f2012-04-24 18:21:07 +0000185int sock_diag_register(const struct sock_diag_handler *hndl)
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +0000186{
187 int err = 0;
188
Dan Carpenter6f8e4ad2011-12-07 20:49:38 +0000189 if (hndl->family >= AF_MAX)
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +0000190 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
Shan Wei8dcf01f2012-04-24 18:21:07 +0000203void sock_diag_unregister(const struct sock_diag_handler *hnld)
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +0000204{
205 int family = hnld->family;
206
Dan Carpenter6f8e4ad2011-12-07 20:49:38 +0000207 if (family >= AF_MAX)
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +0000208 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
Lorenzo Colitti64be0ae2015-12-16 12:30:03 +0900217static int __sock_diag_cmd(struct sk_buff *skb, struct nlmsghdr *nlh)
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +0000218{
219 int err;
Thomas Graf7b468662012-06-26 23:36:11 +0000220 struct sock_diag_req *req = nlmsg_data(nlh);
Shan Wei8dcf01f2012-04-24 18:21:07 +0000221 const struct sock_diag_handler *hndl;
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +0000222
223 if (nlmsg_len(nlh) < sizeof(*req))
224 return -EINVAL;
225
Mathias Krause6e601a52013-02-23 01:13:47 +0000226 if (req->sdiag_family >= AF_MAX)
227 return -EINVAL;
Jeremy Cline66b51b02018-08-13 22:23:13 +0000228 req->sdiag_family = array_index_nospec(req->sdiag_family, AF_MAX);
Mathias Krause6e601a52013-02-23 01:13:47 +0000229
Mathias Krause8e904552013-02-23 01:13:48 +0000230 if (sock_diag_handlers[req->sdiag_family] == NULL)
Xin Longbf2ae2e2018-03-10 18:57:50 +0800231 sock_load_diag_module(req->sdiag_family, 0);
Mathias Krause8e904552013-02-23 01:13:48 +0000232
233 mutex_lock(&sock_diag_table_mutex);
234 hndl = sock_diag_handlers[req->sdiag_family];
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +0000235 if (hndl == NULL)
236 err = -ENOENT;
Lorenzo Colitti64be0ae2015-12-16 12:30:03 +0900237 else if (nlh->nlmsg_type == SOCK_DIAG_BY_FAMILY)
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +0000238 err = hndl->dump(skb, nlh);
Lorenzo Colitti64be0ae2015-12-16 12:30:03 +0900239 else if (nlh->nlmsg_type == SOCK_DESTROY && hndl->destroy)
240 err = hndl->destroy(skb, nlh);
241 else
242 err = -EOPNOTSUPP;
Mathias Krause8e904552013-02-23 01:13:48 +0000243 mutex_unlock(&sock_diag_table_mutex);
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +0000244
245 return err;
246}
247
Johannes Berg2d4bc932017-04-12 14:34:04 +0200248static int sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
249 struct netlink_ext_ack *extack)
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +0000250{
251 int ret;
252
253 switch (nlh->nlmsg_type) {
254 case TCPDIAG_GETSOCK:
255 case DCCPDIAG_GETSOCK:
256 if (inet_rcv_compat == NULL)
Xin Longbf2ae2e2018-03-10 18:57:50 +0800257 sock_load_diag_module(AF_INET, 0);
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +0000258
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:
Lorenzo Colitti64be0ae2015-12-16 12:30:03 +0900268 case SOCK_DESTROY:
269 return __sock_diag_cmd(skb, nlh);
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +0000270 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
Craig Gallekeb4cb002015-06-15 11:26:18 -0400284static 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])
Xin Longbf2ae2e2018-03-10 18:57:50 +0800290 sock_load_diag_module(AF_INET, 0);
Craig Gallekeb4cb002015-06-15 11:26:18 -0400291 break;
292 case SKNLGRP_INET6_TCP_DESTROY:
293 case SKNLGRP_INET6_UDP_DESTROY:
294 if (!sock_diag_handlers[AF_INET6])
Xin Longbf2ae2e2018-03-10 18:57:50 +0800295 sock_load_diag_module(AF_INET6, 0);
Craig Gallekeb4cb002015-06-15 11:26:18 -0400296 break;
297 }
298 return 0;
299}
300
Lorenzo Colitti64be0ae2015-12-16 12:30:03 +0900301int sock_diag_destroy(struct sock *sk, int err)
302{
303 if (!ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN))
304 return -EPERM;
305
306 if (!sk->sk_prot->diag_destroy)
307 return -EOPNOTSUPP;
308
309 return sk->sk_prot->diag_destroy(sk, err);
310}
311EXPORT_SYMBOL_GPL(sock_diag_destroy);
312
Andrey Vagin51d7ccc2012-07-16 04:28:49 +0000313static int __net_init diag_net_init(struct net *net)
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +0000314{
Pablo Neira Ayusoa31f2d12012-06-29 06:15:21 +0000315 struct netlink_kernel_cfg cfg = {
Craig Gallekeb4cb002015-06-15 11:26:18 -0400316 .groups = SKNLGRP_MAX,
Pablo Neira Ayusoa31f2d12012-06-29 06:15:21 +0000317 .input = sock_diag_rcv,
Craig Gallekeb4cb002015-06-15 11:26:18 -0400318 .bind = sock_diag_bind,
319 .flags = NL_CFG_F_NONROOT_RECV,
Pablo Neira Ayusoa31f2d12012-06-29 06:15:21 +0000320 };
321
Pablo Neira Ayuso9f00d972012-09-08 02:53:54 +0000322 net->diag_nlsk = netlink_kernel_create(net, NETLINK_SOCK_DIAG, &cfg);
Andrey Vagin51d7ccc2012-07-16 04:28:49 +0000323 return net->diag_nlsk == NULL ? -ENOMEM : 0;
324}
325
326static void __net_exit diag_net_exit(struct net *net)
327{
328 netlink_kernel_release(net->diag_nlsk);
329 net->diag_nlsk = NULL;
330}
331
332static struct pernet_operations diag_net_ops = {
333 .init = diag_net_init,
334 .exit = diag_net_exit,
335};
336
337static int __init sock_diag_init(void)
338{
Craig Gallekeb4cb002015-06-15 11:26:18 -0400339 broadcast_wq = alloc_workqueue("sock_diag_events", 0, 0);
340 BUG_ON(!broadcast_wq);
Andrey Vagin51d7ccc2012-07-16 04:28:49 +0000341 return register_pernet_subsys(&diag_net_ops);
Pavel Emelyanov8ef874bf2011-12-06 07:59:52 +0000342}
Paul Gortmakerb6191ae2015-10-07 17:27:43 -0400343device_initcall(sock_diag_init);