xref: /linux/net/ipv4/inet_diag.c (revision 3fd6c59042dbba50391e30862beac979491145fe)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * inet_diag.c	Module for monitoring INET transport protocols sockets.
4  *
5  * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/types.h>
11 #include <linux/fcntl.h>
12 #include <linux/random.h>
13 #include <linux/slab.h>
14 #include <linux/cache.h>
15 #include <linux/init.h>
16 #include <linux/time.h>
17 
18 #include <net/icmp.h>
19 #include <net/tcp.h>
20 #include <net/ipv6.h>
21 #include <net/inet_common.h>
22 #include <net/inet_connection_sock.h>
23 #include <net/inet_hashtables.h>
24 #include <net/inet_timewait_sock.h>
25 #include <net/inet6_hashtables.h>
26 #include <net/bpf_sk_storage.h>
27 #include <net/netlink.h>
28 
29 #include <linux/inet.h>
30 #include <linux/stddef.h>
31 
32 #include <linux/inet_diag.h>
33 #include <linux/sock_diag.h>
34 
35 static const struct inet_diag_handler __rcu **inet_diag_table;
36 
37 struct inet_diag_entry {
38 	const __be32 *saddr;
39 	const __be32 *daddr;
40 	u16 sport;
41 	u16 dport;
42 	u16 family;
43 	u16 userlocks;
44 	u32 ifindex;
45 	u32 mark;
46 #ifdef CONFIG_SOCK_CGROUP_DATA
47 	u64 cgroup_id;
48 #endif
49 };
50 
inet_diag_lock_handler(int proto)51 static const struct inet_diag_handler *inet_diag_lock_handler(int proto)
52 {
53 	const struct inet_diag_handler *handler;
54 
55 	if (proto < 0 || proto >= IPPROTO_MAX)
56 		return NULL;
57 
58 	if (!READ_ONCE(inet_diag_table[proto]))
59 		sock_load_diag_module(AF_INET, proto);
60 
61 	rcu_read_lock();
62 	handler = rcu_dereference(inet_diag_table[proto]);
63 	if (handler && !try_module_get(handler->owner))
64 		handler = NULL;
65 	rcu_read_unlock();
66 
67 	return handler;
68 }
69 
inet_diag_unlock_handler(const struct inet_diag_handler * handler)70 static void inet_diag_unlock_handler(const struct inet_diag_handler *handler)
71 {
72 	module_put(handler->owner);
73 }
74 
inet_diag_msg_common_fill(struct inet_diag_msg * r,struct sock * sk)75 void inet_diag_msg_common_fill(struct inet_diag_msg *r, struct sock *sk)
76 {
77 	r->idiag_family = sk->sk_family;
78 
79 	r->id.idiag_sport = htons(sk->sk_num);
80 	r->id.idiag_dport = sk->sk_dport;
81 	r->id.idiag_if = sk->sk_bound_dev_if;
82 	sock_diag_save_cookie(sk, r->id.idiag_cookie);
83 
84 #if IS_ENABLED(CONFIG_IPV6)
85 	if (sk->sk_family == AF_INET6) {
86 		*(struct in6_addr *)r->id.idiag_src = sk->sk_v6_rcv_saddr;
87 		*(struct in6_addr *)r->id.idiag_dst = sk->sk_v6_daddr;
88 	} else
89 #endif
90 	{
91 	memset(&r->id.idiag_src, 0, sizeof(r->id.idiag_src));
92 	memset(&r->id.idiag_dst, 0, sizeof(r->id.idiag_dst));
93 
94 	r->id.idiag_src[0] = sk->sk_rcv_saddr;
95 	r->id.idiag_dst[0] = sk->sk_daddr;
96 	}
97 }
98 EXPORT_SYMBOL_GPL(inet_diag_msg_common_fill);
99 
inet_sk_attr_size(struct sock * sk,const struct inet_diag_req_v2 * req,bool net_admin)100 static size_t inet_sk_attr_size(struct sock *sk,
101 				const struct inet_diag_req_v2 *req,
102 				bool net_admin)
103 {
104 	const struct inet_diag_handler *handler;
105 	size_t aux = 0;
106 
107 	rcu_read_lock();
108 	handler = rcu_dereference(inet_diag_table[req->sdiag_protocol]);
109 	DEBUG_NET_WARN_ON_ONCE(!handler);
110 	if (handler && handler->idiag_get_aux_size)
111 		aux = handler->idiag_get_aux_size(sk, net_admin);
112 	rcu_read_unlock();
113 
114 	return	  nla_total_size(sizeof(struct tcp_info))
115 		+ nla_total_size(sizeof(struct inet_diag_msg))
116 		+ inet_diag_msg_attrs_size()
117 		+ nla_total_size(sizeof(struct inet_diag_meminfo))
118 		+ nla_total_size(SK_MEMINFO_VARS * sizeof(u32))
119 		+ nla_total_size(TCP_CA_NAME_MAX)
120 		+ nla_total_size(sizeof(struct tcpvegas_info))
121 		+ aux
122 		+ 64;
123 }
124 
inet_diag_msg_attrs_fill(struct sock * sk,struct sk_buff * skb,struct inet_diag_msg * r,int ext,struct user_namespace * user_ns,bool net_admin)125 int inet_diag_msg_attrs_fill(struct sock *sk, struct sk_buff *skb,
126 			     struct inet_diag_msg *r, int ext,
127 			     struct user_namespace *user_ns,
128 			     bool net_admin)
129 {
130 	const struct inet_sock *inet = inet_sk(sk);
131 	struct inet_diag_sockopt inet_sockopt;
132 
133 	if (nla_put_u8(skb, INET_DIAG_SHUTDOWN, sk->sk_shutdown))
134 		goto errout;
135 
136 	/* IPv6 dual-stack sockets use inet->tos for IPv4 connections,
137 	 * hence this needs to be included regardless of socket family.
138 	 */
139 	if (ext & (1 << (INET_DIAG_TOS - 1)))
140 		if (nla_put_u8(skb, INET_DIAG_TOS, READ_ONCE(inet->tos)) < 0)
141 			goto errout;
142 
143 #if IS_ENABLED(CONFIG_IPV6)
144 	if (r->idiag_family == AF_INET6) {
145 		if (ext & (1 << (INET_DIAG_TCLASS - 1)))
146 			if (nla_put_u8(skb, INET_DIAG_TCLASS,
147 				       inet6_sk(sk)->tclass) < 0)
148 				goto errout;
149 
150 		if (((1 << sk->sk_state) & (TCPF_LISTEN | TCPF_CLOSE)) &&
151 		    nla_put_u8(skb, INET_DIAG_SKV6ONLY, ipv6_only_sock(sk)))
152 			goto errout;
153 	}
154 #endif
155 
156 	if (net_admin && nla_put_u32(skb, INET_DIAG_MARK, READ_ONCE(sk->sk_mark)))
157 		goto errout;
158 
159 	if (ext & (1 << (INET_DIAG_CLASS_ID - 1)) ||
160 	    ext & (1 << (INET_DIAG_TCLASS - 1))) {
161 		u32 classid = 0;
162 
163 #ifdef CONFIG_SOCK_CGROUP_DATA
164 		classid = sock_cgroup_classid(&sk->sk_cgrp_data);
165 #endif
166 		/* Fallback to socket priority if class id isn't set.
167 		 * Classful qdiscs use it as direct reference to class.
168 		 * For cgroup2 classid is always zero.
169 		 */
170 		if (!classid)
171 			classid = READ_ONCE(sk->sk_priority);
172 
173 		if (nla_put_u32(skb, INET_DIAG_CLASS_ID, classid))
174 			goto errout;
175 	}
176 
177 #ifdef CONFIG_SOCK_CGROUP_DATA
178 	if (nla_put_u64_64bit(skb, INET_DIAG_CGROUP_ID,
179 			      cgroup_id(sock_cgroup_ptr(&sk->sk_cgrp_data)),
180 			      INET_DIAG_PAD))
181 		goto errout;
182 #endif
183 
184 	r->idiag_uid = from_kuid_munged(user_ns, sock_i_uid(sk));
185 	r->idiag_inode = sock_i_ino(sk);
186 
187 	memset(&inet_sockopt, 0, sizeof(inet_sockopt));
188 	inet_sockopt.recverr	= inet_test_bit(RECVERR, sk);
189 	inet_sockopt.is_icsk	= inet_test_bit(IS_ICSK, sk);
190 	inet_sockopt.freebind	= inet_test_bit(FREEBIND, sk);
191 	inet_sockopt.hdrincl	= inet_test_bit(HDRINCL, sk);
192 	inet_sockopt.mc_loop	= inet_test_bit(MC_LOOP, sk);
193 	inet_sockopt.transparent = inet_test_bit(TRANSPARENT, sk);
194 	inet_sockopt.mc_all	= inet_test_bit(MC_ALL, sk);
195 	inet_sockopt.nodefrag	= inet_test_bit(NODEFRAG, sk);
196 	inet_sockopt.bind_address_no_port = inet_test_bit(BIND_ADDRESS_NO_PORT, sk);
197 	inet_sockopt.recverr_rfc4884 = inet_test_bit(RECVERR_RFC4884, sk);
198 	inet_sockopt.defer_connect = inet_test_bit(DEFER_CONNECT, sk);
199 	if (nla_put(skb, INET_DIAG_SOCKOPT, sizeof(inet_sockopt),
200 		    &inet_sockopt))
201 		goto errout;
202 
203 	return 0;
204 errout:
205 	return 1;
206 }
207 EXPORT_SYMBOL_GPL(inet_diag_msg_attrs_fill);
208 
inet_diag_parse_attrs(const struct nlmsghdr * nlh,int hdrlen,struct nlattr ** req_nlas)209 static int inet_diag_parse_attrs(const struct nlmsghdr *nlh, int hdrlen,
210 				 struct nlattr **req_nlas)
211 {
212 	struct nlattr *nla;
213 	int remaining;
214 
215 	nlmsg_for_each_attr(nla, nlh, hdrlen, remaining) {
216 		int type = nla_type(nla);
217 
218 		if (type == INET_DIAG_REQ_PROTOCOL && nla_len(nla) != sizeof(u32))
219 			return -EINVAL;
220 
221 		if (type < __INET_DIAG_REQ_MAX)
222 			req_nlas[type] = nla;
223 	}
224 	return 0;
225 }
226 
inet_diag_get_protocol(const struct inet_diag_req_v2 * req,const struct inet_diag_dump_data * data)227 static int inet_diag_get_protocol(const struct inet_diag_req_v2 *req,
228 				  const struct inet_diag_dump_data *data)
229 {
230 	if (data->req_nlas[INET_DIAG_REQ_PROTOCOL])
231 		return nla_get_u32(data->req_nlas[INET_DIAG_REQ_PROTOCOL]);
232 	return req->sdiag_protocol;
233 }
234 
235 #define MAX_DUMP_ALLOC_SIZE (KMALLOC_MAX_SIZE - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
236 
inet_sk_diag_fill(struct sock * sk,struct inet_connection_sock * icsk,struct sk_buff * skb,struct netlink_callback * cb,const struct inet_diag_req_v2 * req,u16 nlmsg_flags,bool net_admin)237 int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
238 		      struct sk_buff *skb, struct netlink_callback *cb,
239 		      const struct inet_diag_req_v2 *req,
240 		      u16 nlmsg_flags, bool net_admin)
241 {
242 	const struct tcp_congestion_ops *ca_ops;
243 	const struct inet_diag_handler *handler;
244 	struct inet_diag_dump_data *cb_data;
245 	int ext = req->idiag_ext;
246 	struct inet_diag_msg *r;
247 	struct nlmsghdr  *nlh;
248 	struct nlattr *attr;
249 	void *info = NULL;
250 	u8 icsk_pending;
251 	int protocol;
252 
253 	cb_data = cb->data;
254 	protocol = inet_diag_get_protocol(req, cb_data);
255 
256 	/* inet_diag_lock_handler() made sure inet_diag_table[] is stable. */
257 	handler = rcu_dereference_protected(inet_diag_table[protocol], 1);
258 	DEBUG_NET_WARN_ON_ONCE(!handler);
259 	if (!handler)
260 		return -ENXIO;
261 
262 	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
263 			cb->nlh->nlmsg_type, sizeof(*r), nlmsg_flags);
264 	if (!nlh)
265 		return -EMSGSIZE;
266 
267 	r = nlmsg_data(nlh);
268 	BUG_ON(!sk_fullsock(sk));
269 
270 	inet_diag_msg_common_fill(r, sk);
271 	r->idiag_state = sk->sk_state;
272 	r->idiag_timer = 0;
273 	r->idiag_retrans = 0;
274 	r->idiag_expires = 0;
275 
276 	if (inet_diag_msg_attrs_fill(sk, skb, r, ext,
277 				     sk_user_ns(NETLINK_CB(cb->skb).sk),
278 				     net_admin))
279 		goto errout;
280 
281 	if (ext & (1 << (INET_DIAG_MEMINFO - 1))) {
282 		struct inet_diag_meminfo minfo = {
283 			.idiag_rmem = sk_rmem_alloc_get(sk),
284 			.idiag_wmem = READ_ONCE(sk->sk_wmem_queued),
285 			.idiag_fmem = sk_forward_alloc_get(sk),
286 			.idiag_tmem = sk_wmem_alloc_get(sk),
287 		};
288 
289 		if (nla_put(skb, INET_DIAG_MEMINFO, sizeof(minfo), &minfo) < 0)
290 			goto errout;
291 	}
292 
293 	if (ext & (1 << (INET_DIAG_SKMEMINFO - 1)))
294 		if (sock_diag_put_meminfo(sk, skb, INET_DIAG_SKMEMINFO))
295 			goto errout;
296 
297 	/*
298 	 * RAW sockets might have user-defined protocols assigned,
299 	 * so report the one supplied on socket creation.
300 	 */
301 	if (sk->sk_type == SOCK_RAW) {
302 		if (nla_put_u8(skb, INET_DIAG_PROTOCOL, sk->sk_protocol))
303 			goto errout;
304 	}
305 
306 	if (!icsk) {
307 		handler->idiag_get_info(sk, r, NULL);
308 		goto out;
309 	}
310 
311 	icsk_pending = smp_load_acquire(&icsk->icsk_pending);
312 	if (icsk_pending == ICSK_TIME_RETRANS ||
313 	    icsk_pending == ICSK_TIME_REO_TIMEOUT ||
314 	    icsk_pending == ICSK_TIME_LOSS_PROBE) {
315 		r->idiag_timer = 1;
316 		r->idiag_retrans = icsk->icsk_retransmits;
317 		r->idiag_expires =
318 			jiffies_delta_to_msecs(icsk->icsk_timeout - jiffies);
319 	} else if (icsk_pending == ICSK_TIME_PROBE0) {
320 		r->idiag_timer = 4;
321 		r->idiag_retrans = icsk->icsk_probes_out;
322 		r->idiag_expires =
323 			jiffies_delta_to_msecs(icsk->icsk_timeout - jiffies);
324 	} else if (timer_pending(&sk->sk_timer)) {
325 		r->idiag_timer = 2;
326 		r->idiag_retrans = icsk->icsk_probes_out;
327 		r->idiag_expires =
328 			jiffies_delta_to_msecs(sk->sk_timer.expires - jiffies);
329 	}
330 
331 	if ((ext & (1 << (INET_DIAG_INFO - 1))) && handler->idiag_info_size) {
332 		attr = nla_reserve_64bit(skb, INET_DIAG_INFO,
333 					 handler->idiag_info_size,
334 					 INET_DIAG_PAD);
335 		if (!attr)
336 			goto errout;
337 
338 		info = nla_data(attr);
339 	}
340 
341 	if (ext & (1 << (INET_DIAG_CONG - 1))) {
342 		int err = 0;
343 
344 		rcu_read_lock();
345 		ca_ops = READ_ONCE(icsk->icsk_ca_ops);
346 		if (ca_ops)
347 			err = nla_put_string(skb, INET_DIAG_CONG, ca_ops->name);
348 		rcu_read_unlock();
349 		if (err < 0)
350 			goto errout;
351 	}
352 
353 	handler->idiag_get_info(sk, r, info);
354 
355 	if (ext & (1 << (INET_DIAG_INFO - 1)) && handler->idiag_get_aux)
356 		if (handler->idiag_get_aux(sk, net_admin, skb) < 0)
357 			goto errout;
358 
359 	if (sk->sk_state < TCP_TIME_WAIT) {
360 		union tcp_cc_info info;
361 		size_t sz = 0;
362 		int attr;
363 
364 		rcu_read_lock();
365 		ca_ops = READ_ONCE(icsk->icsk_ca_ops);
366 		if (ca_ops && ca_ops->get_info)
367 			sz = ca_ops->get_info(sk, ext, &attr, &info);
368 		rcu_read_unlock();
369 		if (sz && nla_put(skb, attr, sz, &info) < 0)
370 			goto errout;
371 	}
372 
373 	/* Keep it at the end for potential retry with a larger skb,
374 	 * or else do best-effort fitting, which is only done for the
375 	 * first_nlmsg.
376 	 */
377 	if (cb_data->bpf_stg_diag) {
378 		bool first_nlmsg = ((unsigned char *)nlh == skb->data);
379 		unsigned int prev_min_dump_alloc;
380 		unsigned int total_nla_size = 0;
381 		unsigned int msg_len;
382 		int err;
383 
384 		msg_len = skb_tail_pointer(skb) - (unsigned char *)nlh;
385 		err = bpf_sk_storage_diag_put(cb_data->bpf_stg_diag, sk, skb,
386 					      INET_DIAG_SK_BPF_STORAGES,
387 					      &total_nla_size);
388 
389 		if (!err)
390 			goto out;
391 
392 		total_nla_size += msg_len;
393 		prev_min_dump_alloc = cb->min_dump_alloc;
394 		if (total_nla_size > prev_min_dump_alloc)
395 			cb->min_dump_alloc = min_t(u32, total_nla_size,
396 						   MAX_DUMP_ALLOC_SIZE);
397 
398 		if (!first_nlmsg)
399 			goto errout;
400 
401 		if (cb->min_dump_alloc > prev_min_dump_alloc)
402 			/* Retry with pskb_expand_head() with
403 			 * __GFP_DIRECT_RECLAIM
404 			 */
405 			goto errout;
406 
407 		WARN_ON_ONCE(total_nla_size <= prev_min_dump_alloc);
408 
409 		/* Send what we have for this sk
410 		 * and move on to the next sk in the following
411 		 * dump()
412 		 */
413 	}
414 
415 out:
416 	nlmsg_end(skb, nlh);
417 	return 0;
418 
419 errout:
420 	nlmsg_cancel(skb, nlh);
421 	return -EMSGSIZE;
422 }
423 EXPORT_SYMBOL_GPL(inet_sk_diag_fill);
424 
inet_twsk_diag_fill(struct sock * sk,struct sk_buff * skb,struct netlink_callback * cb,u16 nlmsg_flags,bool net_admin)425 static int inet_twsk_diag_fill(struct sock *sk,
426 			       struct sk_buff *skb,
427 			       struct netlink_callback *cb,
428 			       u16 nlmsg_flags, bool net_admin)
429 {
430 	struct inet_timewait_sock *tw = inet_twsk(sk);
431 	struct inet_diag_msg *r;
432 	struct nlmsghdr *nlh;
433 	long tmo;
434 
435 	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid,
436 			cb->nlh->nlmsg_seq, cb->nlh->nlmsg_type,
437 			sizeof(*r), nlmsg_flags);
438 	if (!nlh)
439 		return -EMSGSIZE;
440 
441 	r = nlmsg_data(nlh);
442 	BUG_ON(tw->tw_state != TCP_TIME_WAIT);
443 
444 	inet_diag_msg_common_fill(r, sk);
445 	r->idiag_retrans      = 0;
446 
447 	r->idiag_state	      = READ_ONCE(tw->tw_substate);
448 	r->idiag_timer	      = 3;
449 	tmo = tw->tw_timer.expires - jiffies;
450 	r->idiag_expires      = jiffies_delta_to_msecs(tmo);
451 	r->idiag_rqueue	      = 0;
452 	r->idiag_wqueue	      = 0;
453 	r->idiag_uid	      = 0;
454 	r->idiag_inode	      = 0;
455 
456 	if (net_admin && nla_put_u32(skb, INET_DIAG_MARK,
457 				     tw->tw_mark)) {
458 		nlmsg_cancel(skb, nlh);
459 		return -EMSGSIZE;
460 	}
461 
462 	nlmsg_end(skb, nlh);
463 	return 0;
464 }
465 
inet_req_diag_fill(struct sock * sk,struct sk_buff * skb,struct netlink_callback * cb,u16 nlmsg_flags,bool net_admin)466 static int inet_req_diag_fill(struct sock *sk, struct sk_buff *skb,
467 			      struct netlink_callback *cb,
468 			      u16 nlmsg_flags, bool net_admin)
469 {
470 	struct request_sock *reqsk = inet_reqsk(sk);
471 	struct inet_diag_msg *r;
472 	struct nlmsghdr *nlh;
473 	long tmo;
474 
475 	nlh = nlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
476 			cb->nlh->nlmsg_type, sizeof(*r), nlmsg_flags);
477 	if (!nlh)
478 		return -EMSGSIZE;
479 
480 	r = nlmsg_data(nlh);
481 	inet_diag_msg_common_fill(r, sk);
482 	r->idiag_state = TCP_SYN_RECV;
483 	r->idiag_timer = 1;
484 	r->idiag_retrans = reqsk->num_retrans;
485 
486 	BUILD_BUG_ON(offsetof(struct inet_request_sock, ir_cookie) !=
487 		     offsetof(struct sock, sk_cookie));
488 
489 	tmo = inet_reqsk(sk)->rsk_timer.expires - jiffies;
490 	r->idiag_expires = jiffies_delta_to_msecs(tmo);
491 	r->idiag_rqueue	= 0;
492 	r->idiag_wqueue	= 0;
493 	r->idiag_uid	= 0;
494 	r->idiag_inode	= 0;
495 
496 	if (net_admin && nla_put_u32(skb, INET_DIAG_MARK,
497 				     inet_rsk(reqsk)->ir_mark)) {
498 		nlmsg_cancel(skb, nlh);
499 		return -EMSGSIZE;
500 	}
501 
502 	nlmsg_end(skb, nlh);
503 	return 0;
504 }
505 
sk_diag_fill(struct sock * sk,struct sk_buff * skb,struct netlink_callback * cb,const struct inet_diag_req_v2 * r,u16 nlmsg_flags,bool net_admin)506 static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
507 			struct netlink_callback *cb,
508 			const struct inet_diag_req_v2 *r,
509 			u16 nlmsg_flags, bool net_admin)
510 {
511 	if (sk->sk_state == TCP_TIME_WAIT)
512 		return inet_twsk_diag_fill(sk, skb, cb, nlmsg_flags, net_admin);
513 
514 	if (sk->sk_state == TCP_NEW_SYN_RECV)
515 		return inet_req_diag_fill(sk, skb, cb, nlmsg_flags, net_admin);
516 
517 	return inet_sk_diag_fill(sk, inet_csk(sk), skb, cb, r, nlmsg_flags,
518 				 net_admin);
519 }
520 
inet_diag_find_one_icsk(struct net * net,struct inet_hashinfo * hashinfo,const struct inet_diag_req_v2 * req)521 struct sock *inet_diag_find_one_icsk(struct net *net,
522 				     struct inet_hashinfo *hashinfo,
523 				     const struct inet_diag_req_v2 *req)
524 {
525 	struct sock *sk;
526 
527 	rcu_read_lock();
528 	if (req->sdiag_family == AF_INET)
529 		sk = inet_lookup(net, hashinfo, NULL, 0, req->id.idiag_dst[0],
530 				 req->id.idiag_dport, req->id.idiag_src[0],
531 				 req->id.idiag_sport, req->id.idiag_if);
532 #if IS_ENABLED(CONFIG_IPV6)
533 	else if (req->sdiag_family == AF_INET6) {
534 		if (ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_dst) &&
535 		    ipv6_addr_v4mapped((struct in6_addr *)req->id.idiag_src))
536 			sk = inet_lookup(net, hashinfo, NULL, 0, req->id.idiag_dst[3],
537 					 req->id.idiag_dport, req->id.idiag_src[3],
538 					 req->id.idiag_sport, req->id.idiag_if);
539 		else
540 			sk = inet6_lookup(net, hashinfo, NULL, 0,
541 					  (struct in6_addr *)req->id.idiag_dst,
542 					  req->id.idiag_dport,
543 					  (struct in6_addr *)req->id.idiag_src,
544 					  req->id.idiag_sport,
545 					  req->id.idiag_if);
546 	}
547 #endif
548 	else {
549 		rcu_read_unlock();
550 		return ERR_PTR(-EINVAL);
551 	}
552 	rcu_read_unlock();
553 	if (!sk)
554 		return ERR_PTR(-ENOENT);
555 
556 	if (sock_diag_check_cookie(sk, req->id.idiag_cookie)) {
557 		sock_gen_put(sk);
558 		return ERR_PTR(-ENOENT);
559 	}
560 
561 	return sk;
562 }
563 EXPORT_SYMBOL_GPL(inet_diag_find_one_icsk);
564 
inet_diag_dump_one_icsk(struct inet_hashinfo * hashinfo,struct netlink_callback * cb,const struct inet_diag_req_v2 * req)565 int inet_diag_dump_one_icsk(struct inet_hashinfo *hashinfo,
566 			    struct netlink_callback *cb,
567 			    const struct inet_diag_req_v2 *req)
568 {
569 	struct sk_buff *in_skb = cb->skb;
570 	bool net_admin = netlink_net_capable(in_skb, CAP_NET_ADMIN);
571 	struct net *net = sock_net(in_skb->sk);
572 	struct sk_buff *rep;
573 	struct sock *sk;
574 	int err;
575 
576 	sk = inet_diag_find_one_icsk(net, hashinfo, req);
577 	if (IS_ERR(sk))
578 		return PTR_ERR(sk);
579 
580 	rep = nlmsg_new(inet_sk_attr_size(sk, req, net_admin), GFP_KERNEL);
581 	if (!rep) {
582 		err = -ENOMEM;
583 		goto out;
584 	}
585 
586 	err = sk_diag_fill(sk, rep, cb, req, 0, net_admin);
587 	if (err < 0) {
588 		WARN_ON(err == -EMSGSIZE);
589 		nlmsg_free(rep);
590 		goto out;
591 	}
592 	err = nlmsg_unicast(net->diag_nlsk, rep, NETLINK_CB(in_skb).portid);
593 
594 out:
595 	if (sk)
596 		sock_gen_put(sk);
597 
598 	return err;
599 }
600 EXPORT_SYMBOL_GPL(inet_diag_dump_one_icsk);
601 
inet_diag_cmd_exact(int cmd,struct sk_buff * in_skb,const struct nlmsghdr * nlh,int hdrlen,const struct inet_diag_req_v2 * req)602 static int inet_diag_cmd_exact(int cmd, struct sk_buff *in_skb,
603 			       const struct nlmsghdr *nlh,
604 			       int hdrlen,
605 			       const struct inet_diag_req_v2 *req)
606 {
607 	const struct inet_diag_handler *handler;
608 	struct inet_diag_dump_data dump_data;
609 	int err, protocol;
610 
611 	memset(&dump_data, 0, sizeof(dump_data));
612 	err = inet_diag_parse_attrs(nlh, hdrlen, dump_data.req_nlas);
613 	if (err)
614 		return err;
615 
616 	protocol = inet_diag_get_protocol(req, &dump_data);
617 
618 	handler = inet_diag_lock_handler(protocol);
619 	if (!handler)
620 		return -ENOENT;
621 
622 	if (cmd == SOCK_DIAG_BY_FAMILY) {
623 		struct netlink_callback cb = {
624 			.nlh = nlh,
625 			.skb = in_skb,
626 			.data = &dump_data,
627 		};
628 		err = handler->dump_one(&cb, req);
629 	} else if (cmd == SOCK_DESTROY && handler->destroy) {
630 		err = handler->destroy(in_skb, req);
631 	} else {
632 		err = -EOPNOTSUPP;
633 	}
634 	inet_diag_unlock_handler(handler);
635 
636 	return err;
637 }
638 
bitstring_match(const __be32 * a1,const __be32 * a2,int bits)639 static int bitstring_match(const __be32 *a1, const __be32 *a2, int bits)
640 {
641 	int words = bits >> 5;
642 
643 	bits &= 0x1f;
644 
645 	if (words) {
646 		if (memcmp(a1, a2, words << 2))
647 			return 0;
648 	}
649 	if (bits) {
650 		__be32 w1, w2;
651 		__be32 mask;
652 
653 		w1 = a1[words];
654 		w2 = a2[words];
655 
656 		mask = htonl((0xffffffff) << (32 - bits));
657 
658 		if ((w1 ^ w2) & mask)
659 			return 0;
660 	}
661 
662 	return 1;
663 }
664 
inet_diag_bc_run(const struct nlattr * _bc,const struct inet_diag_entry * entry)665 static int inet_diag_bc_run(const struct nlattr *_bc,
666 			    const struct inet_diag_entry *entry)
667 {
668 	const void *bc = nla_data(_bc);
669 	int len = nla_len(_bc);
670 
671 	while (len > 0) {
672 		int yes = 1;
673 		const struct inet_diag_bc_op *op = bc;
674 
675 		switch (op->code) {
676 		case INET_DIAG_BC_NOP:
677 			break;
678 		case INET_DIAG_BC_JMP:
679 			yes = 0;
680 			break;
681 		case INET_DIAG_BC_S_EQ:
682 			yes = entry->sport == op[1].no;
683 			break;
684 		case INET_DIAG_BC_S_GE:
685 			yes = entry->sport >= op[1].no;
686 			break;
687 		case INET_DIAG_BC_S_LE:
688 			yes = entry->sport <= op[1].no;
689 			break;
690 		case INET_DIAG_BC_D_EQ:
691 			yes = entry->dport == op[1].no;
692 			break;
693 		case INET_DIAG_BC_D_GE:
694 			yes = entry->dport >= op[1].no;
695 			break;
696 		case INET_DIAG_BC_D_LE:
697 			yes = entry->dport <= op[1].no;
698 			break;
699 		case INET_DIAG_BC_AUTO:
700 			yes = !(entry->userlocks & SOCK_BINDPORT_LOCK);
701 			break;
702 		case INET_DIAG_BC_S_COND:
703 		case INET_DIAG_BC_D_COND: {
704 			const struct inet_diag_hostcond *cond;
705 			const __be32 *addr;
706 
707 			cond = (const struct inet_diag_hostcond *)(op + 1);
708 			if (cond->port != -1 &&
709 			    cond->port != (op->code == INET_DIAG_BC_S_COND ?
710 					     entry->sport : entry->dport)) {
711 				yes = 0;
712 				break;
713 			}
714 
715 			if (op->code == INET_DIAG_BC_S_COND)
716 				addr = entry->saddr;
717 			else
718 				addr = entry->daddr;
719 
720 			if (cond->family != AF_UNSPEC &&
721 			    cond->family != entry->family) {
722 				if (entry->family == AF_INET6 &&
723 				    cond->family == AF_INET) {
724 					if (addr[0] == 0 && addr[1] == 0 &&
725 					    addr[2] == htonl(0xffff) &&
726 					    bitstring_match(addr + 3,
727 							    cond->addr,
728 							    cond->prefix_len))
729 						break;
730 				}
731 				yes = 0;
732 				break;
733 			}
734 
735 			if (cond->prefix_len == 0)
736 				break;
737 			if (bitstring_match(addr, cond->addr,
738 					    cond->prefix_len))
739 				break;
740 			yes = 0;
741 			break;
742 		}
743 		case INET_DIAG_BC_DEV_COND: {
744 			u32 ifindex;
745 
746 			ifindex = *((const u32 *)(op + 1));
747 			if (ifindex != entry->ifindex)
748 				yes = 0;
749 			break;
750 		}
751 		case INET_DIAG_BC_MARK_COND: {
752 			struct inet_diag_markcond *cond;
753 
754 			cond = (struct inet_diag_markcond *)(op + 1);
755 			if ((entry->mark & cond->mask) != cond->mark)
756 				yes = 0;
757 			break;
758 		}
759 #ifdef CONFIG_SOCK_CGROUP_DATA
760 		case INET_DIAG_BC_CGROUP_COND: {
761 			u64 cgroup_id;
762 
763 			cgroup_id = get_unaligned((const u64 *)(op + 1));
764 			if (cgroup_id != entry->cgroup_id)
765 				yes = 0;
766 			break;
767 		}
768 #endif
769 		}
770 
771 		if (yes) {
772 			len -= op->yes;
773 			bc += op->yes;
774 		} else {
775 			len -= op->no;
776 			bc += op->no;
777 		}
778 	}
779 	return len == 0;
780 }
781 
782 /* This helper is available for all sockets (ESTABLISH, TIMEWAIT, SYN_RECV)
783  */
entry_fill_addrs(struct inet_diag_entry * entry,const struct sock * sk)784 static void entry_fill_addrs(struct inet_diag_entry *entry,
785 			     const struct sock *sk)
786 {
787 #if IS_ENABLED(CONFIG_IPV6)
788 	if (sk->sk_family == AF_INET6) {
789 		entry->saddr = sk->sk_v6_rcv_saddr.s6_addr32;
790 		entry->daddr = sk->sk_v6_daddr.s6_addr32;
791 	} else
792 #endif
793 	{
794 		entry->saddr = &sk->sk_rcv_saddr;
795 		entry->daddr = &sk->sk_daddr;
796 	}
797 }
798 
inet_diag_bc_sk(const struct nlattr * bc,struct sock * sk)799 int inet_diag_bc_sk(const struct nlattr *bc, struct sock *sk)
800 {
801 	struct inet_sock *inet = inet_sk(sk);
802 	struct inet_diag_entry entry;
803 
804 	if (!bc)
805 		return 1;
806 
807 	entry.family = sk->sk_family;
808 	entry_fill_addrs(&entry, sk);
809 	entry.sport = inet->inet_num;
810 	entry.dport = ntohs(inet->inet_dport);
811 	entry.ifindex = sk->sk_bound_dev_if;
812 	entry.userlocks = sk_fullsock(sk) ? sk->sk_userlocks : 0;
813 	if (sk_fullsock(sk))
814 		entry.mark = READ_ONCE(sk->sk_mark);
815 	else if (sk->sk_state == TCP_NEW_SYN_RECV)
816 		entry.mark = inet_rsk(inet_reqsk(sk))->ir_mark;
817 	else if (sk->sk_state == TCP_TIME_WAIT)
818 		entry.mark = inet_twsk(sk)->tw_mark;
819 	else
820 		entry.mark = 0;
821 #ifdef CONFIG_SOCK_CGROUP_DATA
822 	entry.cgroup_id = sk_fullsock(sk) ?
823 		cgroup_id(sock_cgroup_ptr(&sk->sk_cgrp_data)) : 0;
824 #endif
825 
826 	return inet_diag_bc_run(bc, &entry);
827 }
828 EXPORT_SYMBOL_GPL(inet_diag_bc_sk);
829 
valid_cc(const void * bc,int len,int cc)830 static int valid_cc(const void *bc, int len, int cc)
831 {
832 	while (len >= 0) {
833 		const struct inet_diag_bc_op *op = bc;
834 
835 		if (cc > len)
836 			return 0;
837 		if (cc == len)
838 			return 1;
839 		if (op->yes < 4 || op->yes & 3)
840 			return 0;
841 		len -= op->yes;
842 		bc  += op->yes;
843 	}
844 	return 0;
845 }
846 
847 /* data is u32 ifindex */
valid_devcond(const struct inet_diag_bc_op * op,int len,int * min_len)848 static bool valid_devcond(const struct inet_diag_bc_op *op, int len,
849 			  int *min_len)
850 {
851 	/* Check ifindex space. */
852 	*min_len += sizeof(u32);
853 	if (len < *min_len)
854 		return false;
855 
856 	return true;
857 }
858 /* Validate an inet_diag_hostcond. */
valid_hostcond(const struct inet_diag_bc_op * op,int len,int * min_len)859 static bool valid_hostcond(const struct inet_diag_bc_op *op, int len,
860 			   int *min_len)
861 {
862 	struct inet_diag_hostcond *cond;
863 	int addr_len;
864 
865 	/* Check hostcond space. */
866 	*min_len += sizeof(struct inet_diag_hostcond);
867 	if (len < *min_len)
868 		return false;
869 	cond = (struct inet_diag_hostcond *)(op + 1);
870 
871 	/* Check address family and address length. */
872 	switch (cond->family) {
873 	case AF_UNSPEC:
874 		addr_len = 0;
875 		break;
876 	case AF_INET:
877 		addr_len = sizeof(struct in_addr);
878 		break;
879 	case AF_INET6:
880 		addr_len = sizeof(struct in6_addr);
881 		break;
882 	default:
883 		return false;
884 	}
885 	*min_len += addr_len;
886 	if (len < *min_len)
887 		return false;
888 
889 	/* Check prefix length (in bits) vs address length (in bytes). */
890 	if (cond->prefix_len > 8 * addr_len)
891 		return false;
892 
893 	return true;
894 }
895 
896 /* Validate a port comparison operator. */
valid_port_comparison(const struct inet_diag_bc_op * op,int len,int * min_len)897 static bool valid_port_comparison(const struct inet_diag_bc_op *op,
898 				  int len, int *min_len)
899 {
900 	/* Port comparisons put the port in a follow-on inet_diag_bc_op. */
901 	*min_len += sizeof(struct inet_diag_bc_op);
902 	if (len < *min_len)
903 		return false;
904 	return true;
905 }
906 
valid_markcond(const struct inet_diag_bc_op * op,int len,int * min_len)907 static bool valid_markcond(const struct inet_diag_bc_op *op, int len,
908 			   int *min_len)
909 {
910 	*min_len += sizeof(struct inet_diag_markcond);
911 	return len >= *min_len;
912 }
913 
914 #ifdef CONFIG_SOCK_CGROUP_DATA
valid_cgroupcond(const struct inet_diag_bc_op * op,int len,int * min_len)915 static bool valid_cgroupcond(const struct inet_diag_bc_op *op, int len,
916 			     int *min_len)
917 {
918 	*min_len += sizeof(u64);
919 	return len >= *min_len;
920 }
921 #endif
922 
inet_diag_bc_audit(const struct nlattr * attr,const struct sk_buff * skb)923 static int inet_diag_bc_audit(const struct nlattr *attr,
924 			      const struct sk_buff *skb)
925 {
926 	bool net_admin = netlink_net_capable(skb, CAP_NET_ADMIN);
927 	const void *bytecode, *bc;
928 	int bytecode_len, len;
929 
930 	if (!attr || nla_len(attr) < sizeof(struct inet_diag_bc_op))
931 		return -EINVAL;
932 
933 	bytecode = bc = nla_data(attr);
934 	len = bytecode_len = nla_len(attr);
935 
936 	while (len > 0) {
937 		int min_len = sizeof(struct inet_diag_bc_op);
938 		const struct inet_diag_bc_op *op = bc;
939 
940 		switch (op->code) {
941 		case INET_DIAG_BC_S_COND:
942 		case INET_DIAG_BC_D_COND:
943 			if (!valid_hostcond(bc, len, &min_len))
944 				return -EINVAL;
945 			break;
946 		case INET_DIAG_BC_DEV_COND:
947 			if (!valid_devcond(bc, len, &min_len))
948 				return -EINVAL;
949 			break;
950 		case INET_DIAG_BC_S_EQ:
951 		case INET_DIAG_BC_S_GE:
952 		case INET_DIAG_BC_S_LE:
953 		case INET_DIAG_BC_D_EQ:
954 		case INET_DIAG_BC_D_GE:
955 		case INET_DIAG_BC_D_LE:
956 			if (!valid_port_comparison(bc, len, &min_len))
957 				return -EINVAL;
958 			break;
959 		case INET_DIAG_BC_MARK_COND:
960 			if (!net_admin)
961 				return -EPERM;
962 			if (!valid_markcond(bc, len, &min_len))
963 				return -EINVAL;
964 			break;
965 #ifdef CONFIG_SOCK_CGROUP_DATA
966 		case INET_DIAG_BC_CGROUP_COND:
967 			if (!valid_cgroupcond(bc, len, &min_len))
968 				return -EINVAL;
969 			break;
970 #endif
971 		case INET_DIAG_BC_AUTO:
972 		case INET_DIAG_BC_JMP:
973 		case INET_DIAG_BC_NOP:
974 			break;
975 		default:
976 			return -EINVAL;
977 		}
978 
979 		if (op->code != INET_DIAG_BC_NOP) {
980 			if (op->no < min_len || op->no > len + 4 || op->no & 3)
981 				return -EINVAL;
982 			if (op->no < len &&
983 			    !valid_cc(bytecode, bytecode_len, len - op->no))
984 				return -EINVAL;
985 		}
986 
987 		if (op->yes < min_len || op->yes > len + 4 || op->yes & 3)
988 			return -EINVAL;
989 		bc  += op->yes;
990 		len -= op->yes;
991 	}
992 	return len == 0 ? 0 : -EINVAL;
993 }
994 
twsk_build_assert(void)995 static void twsk_build_assert(void)
996 {
997 	BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_family) !=
998 		     offsetof(struct sock, sk_family));
999 
1000 	BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_num) !=
1001 		     offsetof(struct inet_sock, inet_num));
1002 
1003 	BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_dport) !=
1004 		     offsetof(struct inet_sock, inet_dport));
1005 
1006 	BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_rcv_saddr) !=
1007 		     offsetof(struct inet_sock, inet_rcv_saddr));
1008 
1009 	BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_daddr) !=
1010 		     offsetof(struct inet_sock, inet_daddr));
1011 
1012 #if IS_ENABLED(CONFIG_IPV6)
1013 	BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_v6_rcv_saddr) !=
1014 		     offsetof(struct sock, sk_v6_rcv_saddr));
1015 
1016 	BUILD_BUG_ON(offsetof(struct inet_timewait_sock, tw_v6_daddr) !=
1017 		     offsetof(struct sock, sk_v6_daddr));
1018 #endif
1019 }
1020 
inet_diag_dump_icsk(struct inet_hashinfo * hashinfo,struct sk_buff * skb,struct netlink_callback * cb,const struct inet_diag_req_v2 * r)1021 void inet_diag_dump_icsk(struct inet_hashinfo *hashinfo, struct sk_buff *skb,
1022 			 struct netlink_callback *cb,
1023 			 const struct inet_diag_req_v2 *r)
1024 {
1025 	bool net_admin = netlink_net_capable(cb->skb, CAP_NET_ADMIN);
1026 	struct inet_diag_dump_data *cb_data = cb->data;
1027 	struct net *net = sock_net(skb->sk);
1028 	u32 idiag_states = r->idiag_states;
1029 	int i, num, s_i, s_num;
1030 	struct nlattr *bc;
1031 	struct sock *sk;
1032 
1033 	bc = cb_data->inet_diag_nla_bc;
1034 	if (idiag_states & TCPF_SYN_RECV)
1035 		idiag_states |= TCPF_NEW_SYN_RECV;
1036 	s_i = cb->args[1];
1037 	s_num = num = cb->args[2];
1038 
1039 	if (cb->args[0] == 0) {
1040 		if (!(idiag_states & TCPF_LISTEN) || r->id.idiag_dport)
1041 			goto skip_listen_ht;
1042 
1043 		for (i = s_i; i <= hashinfo->lhash2_mask; i++) {
1044 			struct inet_listen_hashbucket *ilb;
1045 			struct hlist_nulls_node *node;
1046 
1047 			num = 0;
1048 			ilb = &hashinfo->lhash2[i];
1049 
1050 			if (hlist_nulls_empty(&ilb->nulls_head)) {
1051 				s_num = 0;
1052 				continue;
1053 			}
1054 			spin_lock(&ilb->lock);
1055 			sk_nulls_for_each(sk, node, &ilb->nulls_head) {
1056 				struct inet_sock *inet = inet_sk(sk);
1057 
1058 				if (!net_eq(sock_net(sk), net))
1059 					continue;
1060 
1061 				if (num < s_num) {
1062 					num++;
1063 					continue;
1064 				}
1065 
1066 				if (r->sdiag_family != AF_UNSPEC &&
1067 				    sk->sk_family != r->sdiag_family)
1068 					goto next_listen;
1069 
1070 				if (r->id.idiag_sport != inet->inet_sport &&
1071 				    r->id.idiag_sport)
1072 					goto next_listen;
1073 
1074 				if (!inet_diag_bc_sk(bc, sk))
1075 					goto next_listen;
1076 
1077 				if (inet_sk_diag_fill(sk, inet_csk(sk), skb,
1078 						      cb, r, NLM_F_MULTI,
1079 						      net_admin) < 0) {
1080 					spin_unlock(&ilb->lock);
1081 					goto done;
1082 				}
1083 
1084 next_listen:
1085 				++num;
1086 			}
1087 			spin_unlock(&ilb->lock);
1088 
1089 			s_num = 0;
1090 		}
1091 skip_listen_ht:
1092 		cb->args[0] = 1;
1093 		s_i = num = s_num = 0;
1094 	}
1095 
1096 /* Process a maximum of SKARR_SZ sockets at a time when walking hash buckets
1097  * with bh disabled.
1098  */
1099 #define SKARR_SZ 16
1100 
1101 	/* Dump bound but inactive (not listening, connecting, etc.) sockets */
1102 	if (cb->args[0] == 1) {
1103 		if (!(idiag_states & TCPF_BOUND_INACTIVE))
1104 			goto skip_bind_ht;
1105 
1106 		for (i = s_i; i < hashinfo->bhash_size; i++) {
1107 			struct inet_bind_hashbucket *ibb;
1108 			struct inet_bind2_bucket *tb2;
1109 			struct sock *sk_arr[SKARR_SZ];
1110 			int num_arr[SKARR_SZ];
1111 			int idx, accum, res;
1112 
1113 resume_bind_walk:
1114 			num = 0;
1115 			accum = 0;
1116 			ibb = &hashinfo->bhash2[i];
1117 
1118 			if (hlist_empty(&ibb->chain)) {
1119 				s_num = 0;
1120 				continue;
1121 			}
1122 			spin_lock_bh(&ibb->lock);
1123 			inet_bind_bucket_for_each(tb2, &ibb->chain) {
1124 				if (!net_eq(ib2_net(tb2), net))
1125 					continue;
1126 
1127 				sk_for_each_bound(sk, &tb2->owners) {
1128 					struct inet_sock *inet = inet_sk(sk);
1129 
1130 					if (num < s_num)
1131 						goto next_bind;
1132 
1133 					if (sk->sk_state != TCP_CLOSE ||
1134 					    !inet->inet_num)
1135 						goto next_bind;
1136 
1137 					if (r->sdiag_family != AF_UNSPEC &&
1138 					    r->sdiag_family != sk->sk_family)
1139 						goto next_bind;
1140 
1141 					if (!inet_diag_bc_sk(bc, sk))
1142 						goto next_bind;
1143 
1144 					sock_hold(sk);
1145 					num_arr[accum] = num;
1146 					sk_arr[accum] = sk;
1147 					if (++accum == SKARR_SZ)
1148 						goto pause_bind_walk;
1149 next_bind:
1150 					num++;
1151 				}
1152 			}
1153 pause_bind_walk:
1154 			spin_unlock_bh(&ibb->lock);
1155 
1156 			res = 0;
1157 			for (idx = 0; idx < accum; idx++) {
1158 				if (res >= 0) {
1159 					res = inet_sk_diag_fill(sk_arr[idx],
1160 								NULL, skb, cb,
1161 								r, NLM_F_MULTI,
1162 								net_admin);
1163 					if (res < 0)
1164 						num = num_arr[idx];
1165 				}
1166 				sock_put(sk_arr[idx]);
1167 			}
1168 			if (res < 0)
1169 				goto done;
1170 
1171 			cond_resched();
1172 
1173 			if (accum == SKARR_SZ) {
1174 				s_num = num + 1;
1175 				goto resume_bind_walk;
1176 			}
1177 
1178 			s_num = 0;
1179 		}
1180 skip_bind_ht:
1181 		cb->args[0] = 2;
1182 		s_i = num = s_num = 0;
1183 	}
1184 
1185 	if (!(idiag_states & ~TCPF_LISTEN))
1186 		goto out;
1187 
1188 	for (i = s_i; i <= hashinfo->ehash_mask; i++) {
1189 		struct inet_ehash_bucket *head = &hashinfo->ehash[i];
1190 		spinlock_t *lock = inet_ehash_lockp(hashinfo, i);
1191 		struct hlist_nulls_node *node;
1192 		struct sock *sk_arr[SKARR_SZ];
1193 		int num_arr[SKARR_SZ];
1194 		int idx, accum, res;
1195 
1196 		if (hlist_nulls_empty(&head->chain))
1197 			continue;
1198 
1199 		if (i > s_i)
1200 			s_num = 0;
1201 
1202 next_chunk:
1203 		num = 0;
1204 		accum = 0;
1205 		spin_lock_bh(lock);
1206 		sk_nulls_for_each(sk, node, &head->chain) {
1207 			int state;
1208 
1209 			if (!net_eq(sock_net(sk), net))
1210 				continue;
1211 			if (num < s_num)
1212 				goto next_normal;
1213 			state = (sk->sk_state == TCP_TIME_WAIT) ?
1214 				READ_ONCE(inet_twsk(sk)->tw_substate) : sk->sk_state;
1215 			if (!(idiag_states & (1 << state)))
1216 				goto next_normal;
1217 			if (r->sdiag_family != AF_UNSPEC &&
1218 			    sk->sk_family != r->sdiag_family)
1219 				goto next_normal;
1220 			if (r->id.idiag_sport != htons(sk->sk_num) &&
1221 			    r->id.idiag_sport)
1222 				goto next_normal;
1223 			if (r->id.idiag_dport != sk->sk_dport &&
1224 			    r->id.idiag_dport)
1225 				goto next_normal;
1226 			twsk_build_assert();
1227 
1228 			if (!inet_diag_bc_sk(bc, sk))
1229 				goto next_normal;
1230 
1231 			if (!refcount_inc_not_zero(&sk->sk_refcnt))
1232 				goto next_normal;
1233 
1234 			num_arr[accum] = num;
1235 			sk_arr[accum] = sk;
1236 			if (++accum == SKARR_SZ)
1237 				break;
1238 next_normal:
1239 			++num;
1240 		}
1241 		spin_unlock_bh(lock);
1242 		res = 0;
1243 		for (idx = 0; idx < accum; idx++) {
1244 			if (res >= 0) {
1245 				res = sk_diag_fill(sk_arr[idx], skb, cb, r,
1246 						   NLM_F_MULTI, net_admin);
1247 				if (res < 0)
1248 					num = num_arr[idx];
1249 			}
1250 			sock_gen_put(sk_arr[idx]);
1251 		}
1252 		if (res < 0)
1253 			break;
1254 		cond_resched();
1255 		if (accum == SKARR_SZ) {
1256 			s_num = num + 1;
1257 			goto next_chunk;
1258 		}
1259 	}
1260 
1261 done:
1262 	cb->args[1] = i;
1263 	cb->args[2] = num;
1264 out:
1265 	;
1266 }
1267 EXPORT_SYMBOL_GPL(inet_diag_dump_icsk);
1268 
__inet_diag_dump(struct sk_buff * skb,struct netlink_callback * cb,const struct inet_diag_req_v2 * r)1269 static int __inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
1270 			    const struct inet_diag_req_v2 *r)
1271 {
1272 	struct inet_diag_dump_data *cb_data = cb->data;
1273 	const struct inet_diag_handler *handler;
1274 	u32 prev_min_dump_alloc;
1275 	int protocol, err = 0;
1276 
1277 	protocol = inet_diag_get_protocol(r, cb_data);
1278 
1279 again:
1280 	prev_min_dump_alloc = cb->min_dump_alloc;
1281 	handler = inet_diag_lock_handler(protocol);
1282 	if (handler) {
1283 		handler->dump(skb, cb, r);
1284 		inet_diag_unlock_handler(handler);
1285 	} else {
1286 		err = -ENOENT;
1287 	}
1288 	/* The skb is not large enough to fit one sk info and
1289 	 * inet_sk_diag_fill() has requested for a larger skb.
1290 	 */
1291 	if (!skb->len && cb->min_dump_alloc > prev_min_dump_alloc) {
1292 		err = pskb_expand_head(skb, 0, cb->min_dump_alloc, GFP_KERNEL);
1293 		if (!err)
1294 			goto again;
1295 	}
1296 
1297 	return err ? : skb->len;
1298 }
1299 
inet_diag_dump(struct sk_buff * skb,struct netlink_callback * cb)1300 static int inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
1301 {
1302 	return __inet_diag_dump(skb, cb, nlmsg_data(cb->nlh));
1303 }
1304 
__inet_diag_dump_start(struct netlink_callback * cb,int hdrlen)1305 static int __inet_diag_dump_start(struct netlink_callback *cb, int hdrlen)
1306 {
1307 	const struct nlmsghdr *nlh = cb->nlh;
1308 	struct inet_diag_dump_data *cb_data;
1309 	struct sk_buff *skb = cb->skb;
1310 	struct nlattr *nla;
1311 	int err;
1312 
1313 	cb_data = kzalloc(sizeof(*cb_data), GFP_KERNEL);
1314 	if (!cb_data)
1315 		return -ENOMEM;
1316 
1317 	err = inet_diag_parse_attrs(nlh, hdrlen, cb_data->req_nlas);
1318 	if (err) {
1319 		kfree(cb_data);
1320 		return err;
1321 	}
1322 	nla = cb_data->inet_diag_nla_bc;
1323 	if (nla) {
1324 		err = inet_diag_bc_audit(nla, skb);
1325 		if (err) {
1326 			kfree(cb_data);
1327 			return err;
1328 		}
1329 	}
1330 
1331 	nla = cb_data->inet_diag_nla_bpf_stgs;
1332 	if (nla) {
1333 		struct bpf_sk_storage_diag *bpf_stg_diag;
1334 
1335 		bpf_stg_diag = bpf_sk_storage_diag_alloc(nla);
1336 		if (IS_ERR(bpf_stg_diag)) {
1337 			kfree(cb_data);
1338 			return PTR_ERR(bpf_stg_diag);
1339 		}
1340 		cb_data->bpf_stg_diag = bpf_stg_diag;
1341 	}
1342 
1343 	cb->data = cb_data;
1344 	return 0;
1345 }
1346 
inet_diag_dump_start(struct netlink_callback * cb)1347 static int inet_diag_dump_start(struct netlink_callback *cb)
1348 {
1349 	return __inet_diag_dump_start(cb, sizeof(struct inet_diag_req_v2));
1350 }
1351 
inet_diag_dump_start_compat(struct netlink_callback * cb)1352 static int inet_diag_dump_start_compat(struct netlink_callback *cb)
1353 {
1354 	return __inet_diag_dump_start(cb, sizeof(struct inet_diag_req));
1355 }
1356 
inet_diag_dump_done(struct netlink_callback * cb)1357 static int inet_diag_dump_done(struct netlink_callback *cb)
1358 {
1359 	struct inet_diag_dump_data *cb_data = cb->data;
1360 
1361 	bpf_sk_storage_diag_free(cb_data->bpf_stg_diag);
1362 	kfree(cb->data);
1363 
1364 	return 0;
1365 }
1366 
inet_diag_type2proto(int type)1367 static int inet_diag_type2proto(int type)
1368 {
1369 	switch (type) {
1370 	case TCPDIAG_GETSOCK:
1371 		return IPPROTO_TCP;
1372 	case DCCPDIAG_GETSOCK:
1373 		return IPPROTO_DCCP;
1374 	default:
1375 		return 0;
1376 	}
1377 }
1378 
inet_diag_dump_compat(struct sk_buff * skb,struct netlink_callback * cb)1379 static int inet_diag_dump_compat(struct sk_buff *skb,
1380 				 struct netlink_callback *cb)
1381 {
1382 	struct inet_diag_req *rc = nlmsg_data(cb->nlh);
1383 	struct inet_diag_req_v2 req;
1384 
1385 	req.sdiag_family = AF_UNSPEC; /* compatibility */
1386 	req.sdiag_protocol = inet_diag_type2proto(cb->nlh->nlmsg_type);
1387 	req.idiag_ext = rc->idiag_ext;
1388 	req.pad = 0;
1389 	req.idiag_states = rc->idiag_states;
1390 	req.id = rc->id;
1391 
1392 	return __inet_diag_dump(skb, cb, &req);
1393 }
1394 
inet_diag_get_exact_compat(struct sk_buff * in_skb,const struct nlmsghdr * nlh)1395 static int inet_diag_get_exact_compat(struct sk_buff *in_skb,
1396 				      const struct nlmsghdr *nlh)
1397 {
1398 	struct inet_diag_req *rc = nlmsg_data(nlh);
1399 	struct inet_diag_req_v2 req;
1400 
1401 	req.sdiag_family = rc->idiag_family;
1402 	req.sdiag_protocol = inet_diag_type2proto(nlh->nlmsg_type);
1403 	req.idiag_ext = rc->idiag_ext;
1404 	req.pad = 0;
1405 	req.idiag_states = rc->idiag_states;
1406 	req.id = rc->id;
1407 
1408 	return inet_diag_cmd_exact(SOCK_DIAG_BY_FAMILY, in_skb, nlh,
1409 				   sizeof(struct inet_diag_req), &req);
1410 }
1411 
inet_diag_rcv_msg_compat(struct sk_buff * skb,struct nlmsghdr * nlh)1412 static int inet_diag_rcv_msg_compat(struct sk_buff *skb, struct nlmsghdr *nlh)
1413 {
1414 	int hdrlen = sizeof(struct inet_diag_req);
1415 	struct net *net = sock_net(skb->sk);
1416 
1417 	if (nlh->nlmsg_type >= INET_DIAG_GETSOCK_MAX ||
1418 	    nlmsg_len(nlh) < hdrlen)
1419 		return -EINVAL;
1420 
1421 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
1422 		struct netlink_dump_control c = {
1423 			.start = inet_diag_dump_start_compat,
1424 			.done = inet_diag_dump_done,
1425 			.dump = inet_diag_dump_compat,
1426 		};
1427 		return netlink_dump_start(net->diag_nlsk, skb, nlh, &c);
1428 	}
1429 
1430 	return inet_diag_get_exact_compat(skb, nlh);
1431 }
1432 
inet_diag_handler_cmd(struct sk_buff * skb,struct nlmsghdr * h)1433 static int inet_diag_handler_cmd(struct sk_buff *skb, struct nlmsghdr *h)
1434 {
1435 	int hdrlen = sizeof(struct inet_diag_req_v2);
1436 	struct net *net = sock_net(skb->sk);
1437 
1438 	if (nlmsg_len(h) < hdrlen)
1439 		return -EINVAL;
1440 
1441 	if (h->nlmsg_type == SOCK_DIAG_BY_FAMILY &&
1442 	    h->nlmsg_flags & NLM_F_DUMP) {
1443 		struct netlink_dump_control c = {
1444 			.start = inet_diag_dump_start,
1445 			.done = inet_diag_dump_done,
1446 			.dump = inet_diag_dump,
1447 		};
1448 		return netlink_dump_start(net->diag_nlsk, skb, h, &c);
1449 	}
1450 
1451 	return inet_diag_cmd_exact(h->nlmsg_type, skb, h, hdrlen,
1452 				   nlmsg_data(h));
1453 }
1454 
1455 static
inet_diag_handler_get_info(struct sk_buff * skb,struct sock * sk)1456 int inet_diag_handler_get_info(struct sk_buff *skb, struct sock *sk)
1457 {
1458 	const struct inet_diag_handler *handler;
1459 	struct nlmsghdr *nlh;
1460 	struct nlattr *attr;
1461 	struct inet_diag_msg *r;
1462 	void *info = NULL;
1463 	int err = 0;
1464 
1465 	nlh = nlmsg_put(skb, 0, 0, SOCK_DIAG_BY_FAMILY, sizeof(*r), 0);
1466 	if (!nlh)
1467 		return -ENOMEM;
1468 
1469 	r = nlmsg_data(nlh);
1470 	memset(r, 0, sizeof(*r));
1471 	inet_diag_msg_common_fill(r, sk);
1472 	if (sk->sk_type == SOCK_DGRAM || sk->sk_type == SOCK_STREAM)
1473 		r->id.idiag_sport = inet_sk(sk)->inet_sport;
1474 	r->idiag_state = sk->sk_state;
1475 
1476 	if ((err = nla_put_u8(skb, INET_DIAG_PROTOCOL, sk->sk_protocol))) {
1477 		nlmsg_cancel(skb, nlh);
1478 		return err;
1479 	}
1480 
1481 	handler = inet_diag_lock_handler(sk->sk_protocol);
1482 	if (!handler) {
1483 		nlmsg_cancel(skb, nlh);
1484 		return -ENOENT;
1485 	}
1486 
1487 	attr = handler->idiag_info_size
1488 		? nla_reserve_64bit(skb, INET_DIAG_INFO,
1489 				    handler->idiag_info_size,
1490 				    INET_DIAG_PAD)
1491 		: NULL;
1492 	if (attr)
1493 		info = nla_data(attr);
1494 
1495 	handler->idiag_get_info(sk, r, info);
1496 	inet_diag_unlock_handler(handler);
1497 
1498 	nlmsg_end(skb, nlh);
1499 	return 0;
1500 }
1501 
1502 static const struct sock_diag_handler inet_diag_handler = {
1503 	.owner = THIS_MODULE,
1504 	.family = AF_INET,
1505 	.dump = inet_diag_handler_cmd,
1506 	.get_info = inet_diag_handler_get_info,
1507 	.destroy = inet_diag_handler_cmd,
1508 };
1509 
1510 static const struct sock_diag_handler inet6_diag_handler = {
1511 	.owner = THIS_MODULE,
1512 	.family = AF_INET6,
1513 	.dump = inet_diag_handler_cmd,
1514 	.get_info = inet_diag_handler_get_info,
1515 	.destroy = inet_diag_handler_cmd,
1516 };
1517 
inet_diag_register(const struct inet_diag_handler * h)1518 int inet_diag_register(const struct inet_diag_handler *h)
1519 {
1520 	const __u16 type = h->idiag_type;
1521 
1522 	if (type >= IPPROTO_MAX)
1523 		return -EINVAL;
1524 
1525 	return !cmpxchg((const struct inet_diag_handler **)&inet_diag_table[type],
1526 			NULL, h) ? 0 : -EEXIST;
1527 }
1528 EXPORT_SYMBOL_GPL(inet_diag_register);
1529 
inet_diag_unregister(const struct inet_diag_handler * h)1530 void inet_diag_unregister(const struct inet_diag_handler *h)
1531 {
1532 	const __u16 type = h->idiag_type;
1533 
1534 	if (type >= IPPROTO_MAX)
1535 		return;
1536 
1537 	xchg((const struct inet_diag_handler **)&inet_diag_table[type],
1538 	     NULL);
1539 }
1540 EXPORT_SYMBOL_GPL(inet_diag_unregister);
1541 
1542 static const struct sock_diag_inet_compat inet_diag_compat = {
1543 	.owner	= THIS_MODULE,
1544 	.fn	= inet_diag_rcv_msg_compat,
1545 };
1546 
inet_diag_init(void)1547 static int __init inet_diag_init(void)
1548 {
1549 	const int inet_diag_table_size = (IPPROTO_MAX *
1550 					  sizeof(struct inet_diag_handler *));
1551 	int err = -ENOMEM;
1552 
1553 	inet_diag_table = kzalloc(inet_diag_table_size, GFP_KERNEL);
1554 	if (!inet_diag_table)
1555 		goto out;
1556 
1557 	err = sock_diag_register(&inet_diag_handler);
1558 	if (err)
1559 		goto out_free_nl;
1560 
1561 	err = sock_diag_register(&inet6_diag_handler);
1562 	if (err)
1563 		goto out_free_inet;
1564 
1565 	sock_diag_register_inet_compat(&inet_diag_compat);
1566 out:
1567 	return err;
1568 
1569 out_free_inet:
1570 	sock_diag_unregister(&inet_diag_handler);
1571 out_free_nl:
1572 	kfree(inet_diag_table);
1573 	goto out;
1574 }
1575 
inet_diag_exit(void)1576 static void __exit inet_diag_exit(void)
1577 {
1578 	sock_diag_unregister(&inet6_diag_handler);
1579 	sock_diag_unregister(&inet_diag_handler);
1580 	sock_diag_unregister_inet_compat(&inet_diag_compat);
1581 	kfree(inet_diag_table);
1582 }
1583 
1584 module_init(inet_diag_init);
1585 module_exit(inet_diag_exit);
1586 MODULE_LICENSE("GPL");
1587 MODULE_DESCRIPTION("INET/INET6: socket monitoring via SOCK_DIAG");
1588 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 2 /* AF_INET */);
1589 MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_NETLINK, NETLINK_SOCK_DIAG, 10 /* AF_INET6 */);
1590