xref: /openbmc/linux/net/ipv4/inet_diag.c (revision a029fe26)
1 /*
2  * inet_diag.c	Module for monitoring INET transport protocols sockets.
3  *
4  * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
5  *
6  *	This program is free software; you can redistribute it and/or
7  *      modify it under the terms of the GNU General Public License
8  *      as published by the Free Software Foundation; either version
9  *      2 of the License, or (at your option) any later version.
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/fcntl.h>
16 #include <linux/random.h>
17 #include <linux/slab.h>
18 #include <linux/cache.h>
19 #include <linux/init.h>
20 #include <linux/time.h>
21 
22 #include <net/icmp.h>
23 #include <net/tcp.h>
24 #include <net/ipv6.h>
25 #include <net/inet_common.h>
26 #include <net/inet_connection_sock.h>
27 #include <net/inet_hashtables.h>
28 #include <net/inet_timewait_sock.h>
29 #include <net/inet6_hashtables.h>
30 #include <net/netlink.h>
31 
32 #include <linux/inet.h>
33 #include <linux/stddef.h>
34 
35 #include <linux/inet_diag.h>
36 #include <linux/sock_diag.h>
37 
38 static const struct inet_diag_handler **inet_diag_table;
39 
40 struct inet_diag_entry {
41 	__be32 *saddr;
42 	__be32 *daddr;
43 	u16 sport;
44 	u16 dport;
45 	u16 family;
46 	u16 userlocks;
47 };
48 
49 static struct sock *sdiagnl;
50 
51 #define INET_DIAG_PUT(skb, attrtype, attrlen) \
52 	RTA_DATA(__RTA_PUT(skb, attrtype, attrlen))
53 
54 static DEFINE_MUTEX(inet_diag_table_mutex);
55 
56 static const struct inet_diag_handler *inet_diag_lock_handler(int proto)
57 {
58 	if (!inet_diag_table[proto])
59 		request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
60 			       NETLINK_SOCK_DIAG, proto);
61 
62 	mutex_lock(&inet_diag_table_mutex);
63 	if (!inet_diag_table[proto])
64 		return ERR_PTR(-ENOENT);
65 
66 	return inet_diag_table[proto];
67 }
68 
69 static inline void inet_diag_unlock_handler(
70 	const struct inet_diag_handler *handler)
71 {
72 	mutex_unlock(&inet_diag_table_mutex);
73 }
74 
75 static int inet_csk_diag_fill(struct sock *sk,
76 			      struct sk_buff *skb, struct inet_diag_req *req,
77 			      u32 pid, u32 seq, u16 nlmsg_flags,
78 			      const struct nlmsghdr *unlh)
79 {
80 	const struct inet_sock *inet = inet_sk(sk);
81 	const struct inet_connection_sock *icsk = inet_csk(sk);
82 	struct inet_diag_msg *r;
83 	struct nlmsghdr  *nlh;
84 	void *info = NULL;
85 	struct inet_diag_meminfo  *minfo = NULL;
86 	unsigned char	 *b = skb_tail_pointer(skb);
87 	const struct inet_diag_handler *handler;
88 	int ext = req->idiag_ext;
89 
90 	handler = inet_diag_table[req->sdiag_protocol];
91 	BUG_ON(handler == NULL);
92 
93 	nlh = NLMSG_PUT(skb, pid, seq, unlh->nlmsg_type, sizeof(*r));
94 	nlh->nlmsg_flags = nlmsg_flags;
95 
96 	r = NLMSG_DATA(nlh);
97 	BUG_ON(sk->sk_state == TCP_TIME_WAIT);
98 
99 	if (ext & (1 << (INET_DIAG_MEMINFO - 1)))
100 		minfo = INET_DIAG_PUT(skb, INET_DIAG_MEMINFO, sizeof(*minfo));
101 
102 	if (ext & (1 << (INET_DIAG_INFO - 1)))
103 		info = INET_DIAG_PUT(skb, INET_DIAG_INFO,
104 				     handler->idiag_info_size);
105 
106 	if ((ext & (1 << (INET_DIAG_CONG - 1))) && icsk->icsk_ca_ops) {
107 		const size_t len = strlen(icsk->icsk_ca_ops->name);
108 
109 		strcpy(INET_DIAG_PUT(skb, INET_DIAG_CONG, len + 1),
110 		       icsk->icsk_ca_ops->name);
111 	}
112 
113 	r->idiag_family = sk->sk_family;
114 	r->idiag_state = sk->sk_state;
115 	r->idiag_timer = 0;
116 	r->idiag_retrans = 0;
117 
118 	r->id.idiag_if = sk->sk_bound_dev_if;
119 	r->id.idiag_cookie[0] = (u32)(unsigned long)sk;
120 	r->id.idiag_cookie[1] = (u32)(((unsigned long)sk >> 31) >> 1);
121 
122 	r->id.idiag_sport = inet->inet_sport;
123 	r->id.idiag_dport = inet->inet_dport;
124 	r->id.idiag_src[0] = inet->inet_rcv_saddr;
125 	r->id.idiag_dst[0] = inet->inet_daddr;
126 
127 	/* IPv6 dual-stack sockets use inet->tos for IPv4 connections,
128 	 * hence this needs to be included regardless of socket family.
129 	 */
130 	if (ext & (1 << (INET_DIAG_TOS - 1)))
131 		RTA_PUT_U8(skb, INET_DIAG_TOS, inet->tos);
132 
133 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
134 	if (r->idiag_family == AF_INET6) {
135 		const struct ipv6_pinfo *np = inet6_sk(sk);
136 
137 		*(struct in6_addr *)r->id.idiag_src = np->rcv_saddr;
138 		*(struct in6_addr *)r->id.idiag_dst = np->daddr;
139 		if (ext & (1 << (INET_DIAG_TCLASS - 1)))
140 			RTA_PUT_U8(skb, INET_DIAG_TCLASS, np->tclass);
141 	}
142 #endif
143 
144 #define EXPIRES_IN_MS(tmo)  DIV_ROUND_UP((tmo - jiffies) * 1000, HZ)
145 
146 	if (icsk->icsk_pending == ICSK_TIME_RETRANS) {
147 		r->idiag_timer = 1;
148 		r->idiag_retrans = icsk->icsk_retransmits;
149 		r->idiag_expires = EXPIRES_IN_MS(icsk->icsk_timeout);
150 	} else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
151 		r->idiag_timer = 4;
152 		r->idiag_retrans = icsk->icsk_probes_out;
153 		r->idiag_expires = EXPIRES_IN_MS(icsk->icsk_timeout);
154 	} else if (timer_pending(&sk->sk_timer)) {
155 		r->idiag_timer = 2;
156 		r->idiag_retrans = icsk->icsk_probes_out;
157 		r->idiag_expires = EXPIRES_IN_MS(sk->sk_timer.expires);
158 	} else {
159 		r->idiag_timer = 0;
160 		r->idiag_expires = 0;
161 	}
162 #undef EXPIRES_IN_MS
163 
164 	r->idiag_uid = sock_i_uid(sk);
165 	r->idiag_inode = sock_i_ino(sk);
166 
167 	if (minfo) {
168 		minfo->idiag_rmem = sk_rmem_alloc_get(sk);
169 		minfo->idiag_wmem = sk->sk_wmem_queued;
170 		minfo->idiag_fmem = sk->sk_forward_alloc;
171 		minfo->idiag_tmem = sk_wmem_alloc_get(sk);
172 	}
173 
174 	handler->idiag_get_info(sk, r, info);
175 
176 	if (sk->sk_state < TCP_TIME_WAIT &&
177 	    icsk->icsk_ca_ops && icsk->icsk_ca_ops->get_info)
178 		icsk->icsk_ca_ops->get_info(sk, ext, skb);
179 
180 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
181 	return skb->len;
182 
183 rtattr_failure:
184 nlmsg_failure:
185 	nlmsg_trim(skb, b);
186 	return -EMSGSIZE;
187 }
188 
189 static int inet_twsk_diag_fill(struct inet_timewait_sock *tw,
190 			       struct sk_buff *skb, struct inet_diag_req *req,
191 			       u32 pid, u32 seq, u16 nlmsg_flags,
192 			       const struct nlmsghdr *unlh)
193 {
194 	long tmo;
195 	struct inet_diag_msg *r;
196 	const unsigned char *previous_tail = skb_tail_pointer(skb);
197 	struct nlmsghdr *nlh = NLMSG_PUT(skb, pid, seq,
198 					 unlh->nlmsg_type, sizeof(*r));
199 
200 	r = NLMSG_DATA(nlh);
201 	BUG_ON(tw->tw_state != TCP_TIME_WAIT);
202 
203 	nlh->nlmsg_flags = nlmsg_flags;
204 
205 	tmo = tw->tw_ttd - jiffies;
206 	if (tmo < 0)
207 		tmo = 0;
208 
209 	r->idiag_family	      = tw->tw_family;
210 	r->idiag_retrans      = 0;
211 	r->id.idiag_if	      = tw->tw_bound_dev_if;
212 	r->id.idiag_cookie[0] = (u32)(unsigned long)tw;
213 	r->id.idiag_cookie[1] = (u32)(((unsigned long)tw >> 31) >> 1);
214 	r->id.idiag_sport     = tw->tw_sport;
215 	r->id.idiag_dport     = tw->tw_dport;
216 	r->id.idiag_src[0]    = tw->tw_rcv_saddr;
217 	r->id.idiag_dst[0]    = tw->tw_daddr;
218 	r->idiag_state	      = tw->tw_substate;
219 	r->idiag_timer	      = 3;
220 	r->idiag_expires      = DIV_ROUND_UP(tmo * 1000, HZ);
221 	r->idiag_rqueue	      = 0;
222 	r->idiag_wqueue	      = 0;
223 	r->idiag_uid	      = 0;
224 	r->idiag_inode	      = 0;
225 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
226 	if (tw->tw_family == AF_INET6) {
227 		const struct inet6_timewait_sock *tw6 =
228 						inet6_twsk((struct sock *)tw);
229 
230 		*(struct in6_addr *)r->id.idiag_src = tw6->tw_v6_rcv_saddr;
231 		*(struct in6_addr *)r->id.idiag_dst = tw6->tw_v6_daddr;
232 	}
233 #endif
234 	nlh->nlmsg_len = skb_tail_pointer(skb) - previous_tail;
235 	return skb->len;
236 nlmsg_failure:
237 	nlmsg_trim(skb, previous_tail);
238 	return -EMSGSIZE;
239 }
240 
241 static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
242 			struct inet_diag_req *r, u32 pid, u32 seq, u16 nlmsg_flags,
243 			const struct nlmsghdr *unlh)
244 {
245 	if (sk->sk_state == TCP_TIME_WAIT)
246 		return inet_twsk_diag_fill((struct inet_timewait_sock *)sk,
247 					   skb, r, pid, seq, nlmsg_flags,
248 					   unlh);
249 	return inet_csk_diag_fill(sk, skb, r, pid, seq, nlmsg_flags, unlh);
250 }
251 
252 static int inet_diag_get_exact(struct sk_buff *in_skb,
253 			       const struct nlmsghdr *nlh,
254 			       struct inet_diag_req *req)
255 {
256 	int err;
257 	struct sock *sk;
258 	struct sk_buff *rep;
259 	struct inet_hashinfo *hashinfo;
260 	const struct inet_diag_handler *handler;
261 
262 	handler = inet_diag_lock_handler(req->sdiag_protocol);
263 	if (IS_ERR(handler)) {
264 		err = PTR_ERR(handler);
265 		goto unlock;
266 	}
267 
268 	hashinfo = handler->idiag_hashinfo;
269 	err = -EINVAL;
270 
271 	if (req->sdiag_family == AF_INET) {
272 		sk = inet_lookup(&init_net, hashinfo, req->id.idiag_dst[0],
273 				 req->id.idiag_dport, req->id.idiag_src[0],
274 				 req->id.idiag_sport, req->id.idiag_if);
275 	}
276 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
277 	else if (req->sdiag_family == AF_INET6) {
278 		sk = inet6_lookup(&init_net, hashinfo,
279 				  (struct in6_addr *)req->id.idiag_dst,
280 				  req->id.idiag_dport,
281 				  (struct in6_addr *)req->id.idiag_src,
282 				  req->id.idiag_sport,
283 				  req->id.idiag_if);
284 	}
285 #endif
286 	else {
287 		goto unlock;
288 	}
289 
290 	err = -ENOENT;
291 	if (sk == NULL)
292 		goto unlock;
293 
294 	err = -ESTALE;
295 	if ((req->id.idiag_cookie[0] != INET_DIAG_NOCOOKIE ||
296 	     req->id.idiag_cookie[1] != INET_DIAG_NOCOOKIE) &&
297 	    ((u32)(unsigned long)sk != req->id.idiag_cookie[0] ||
298 	     (u32)((((unsigned long)sk) >> 31) >> 1) != req->id.idiag_cookie[1]))
299 		goto out;
300 
301 	err = -ENOMEM;
302 	rep = alloc_skb(NLMSG_SPACE((sizeof(struct inet_diag_msg) +
303 				     sizeof(struct inet_diag_meminfo) +
304 				     handler->idiag_info_size + 64)),
305 			GFP_KERNEL);
306 	if (!rep)
307 		goto out;
308 
309 	err = sk_diag_fill(sk, rep, req,
310 			   NETLINK_CB(in_skb).pid,
311 			   nlh->nlmsg_seq, 0, nlh);
312 	if (err < 0) {
313 		WARN_ON(err == -EMSGSIZE);
314 		kfree_skb(rep);
315 		goto out;
316 	}
317 	err = netlink_unicast(sdiagnl, rep, NETLINK_CB(in_skb).pid,
318 			      MSG_DONTWAIT);
319 	if (err > 0)
320 		err = 0;
321 
322 out:
323 	if (sk) {
324 		if (sk->sk_state == TCP_TIME_WAIT)
325 			inet_twsk_put((struct inet_timewait_sock *)sk);
326 		else
327 			sock_put(sk);
328 	}
329 unlock:
330 	inet_diag_unlock_handler(handler);
331 	return err;
332 }
333 
334 static int bitstring_match(const __be32 *a1, const __be32 *a2, int bits)
335 {
336 	int words = bits >> 5;
337 
338 	bits &= 0x1f;
339 
340 	if (words) {
341 		if (memcmp(a1, a2, words << 2))
342 			return 0;
343 	}
344 	if (bits) {
345 		__be32 w1, w2;
346 		__be32 mask;
347 
348 		w1 = a1[words];
349 		w2 = a2[words];
350 
351 		mask = htonl((0xffffffff) << (32 - bits));
352 
353 		if ((w1 ^ w2) & mask)
354 			return 0;
355 	}
356 
357 	return 1;
358 }
359 
360 
361 static int inet_diag_bc_run(const void *bc, int len,
362 			    const struct inet_diag_entry *entry)
363 {
364 	while (len > 0) {
365 		int yes = 1;
366 		const struct inet_diag_bc_op *op = bc;
367 
368 		switch (op->code) {
369 		case INET_DIAG_BC_NOP:
370 			break;
371 		case INET_DIAG_BC_JMP:
372 			yes = 0;
373 			break;
374 		case INET_DIAG_BC_S_GE:
375 			yes = entry->sport >= op[1].no;
376 			break;
377 		case INET_DIAG_BC_S_LE:
378 			yes = entry->sport <= op[1].no;
379 			break;
380 		case INET_DIAG_BC_D_GE:
381 			yes = entry->dport >= op[1].no;
382 			break;
383 		case INET_DIAG_BC_D_LE:
384 			yes = entry->dport <= op[1].no;
385 			break;
386 		case INET_DIAG_BC_AUTO:
387 			yes = !(entry->userlocks & SOCK_BINDPORT_LOCK);
388 			break;
389 		case INET_DIAG_BC_S_COND:
390 		case INET_DIAG_BC_D_COND: {
391 			struct inet_diag_hostcond *cond;
392 			__be32 *addr;
393 
394 			cond = (struct inet_diag_hostcond *)(op + 1);
395 			if (cond->port != -1 &&
396 			    cond->port != (op->code == INET_DIAG_BC_S_COND ?
397 					     entry->sport : entry->dport)) {
398 				yes = 0;
399 				break;
400 			}
401 
402 			if (cond->prefix_len == 0)
403 				break;
404 
405 			if (op->code == INET_DIAG_BC_S_COND)
406 				addr = entry->saddr;
407 			else
408 				addr = entry->daddr;
409 
410 			if (bitstring_match(addr, cond->addr,
411 					    cond->prefix_len))
412 				break;
413 			if (entry->family == AF_INET6 &&
414 			    cond->family == AF_INET) {
415 				if (addr[0] == 0 && addr[1] == 0 &&
416 				    addr[2] == htonl(0xffff) &&
417 				    bitstring_match(addr + 3, cond->addr,
418 						    cond->prefix_len))
419 					break;
420 			}
421 			yes = 0;
422 			break;
423 		}
424 		}
425 
426 		if (yes) {
427 			len -= op->yes;
428 			bc += op->yes;
429 		} else {
430 			len -= op->no;
431 			bc += op->no;
432 		}
433 	}
434 	return len == 0;
435 }
436 
437 static int valid_cc(const void *bc, int len, int cc)
438 {
439 	while (len >= 0) {
440 		const struct inet_diag_bc_op *op = bc;
441 
442 		if (cc > len)
443 			return 0;
444 		if (cc == len)
445 			return 1;
446 		if (op->yes < 4 || op->yes & 3)
447 			return 0;
448 		len -= op->yes;
449 		bc  += op->yes;
450 	}
451 	return 0;
452 }
453 
454 static int inet_diag_bc_audit(const void *bytecode, int bytecode_len)
455 {
456 	const void *bc = bytecode;
457 	int  len = bytecode_len;
458 
459 	while (len > 0) {
460 		const struct inet_diag_bc_op *op = bc;
461 
462 //printk("BC: %d %d %d {%d} / %d\n", op->code, op->yes, op->no, op[1].no, len);
463 		switch (op->code) {
464 		case INET_DIAG_BC_AUTO:
465 		case INET_DIAG_BC_S_COND:
466 		case INET_DIAG_BC_D_COND:
467 		case INET_DIAG_BC_S_GE:
468 		case INET_DIAG_BC_S_LE:
469 		case INET_DIAG_BC_D_GE:
470 		case INET_DIAG_BC_D_LE:
471 		case INET_DIAG_BC_JMP:
472 			if (op->no < 4 || op->no > len + 4 || op->no & 3)
473 				return -EINVAL;
474 			if (op->no < len &&
475 			    !valid_cc(bytecode, bytecode_len, len - op->no))
476 				return -EINVAL;
477 			break;
478 		case INET_DIAG_BC_NOP:
479 			break;
480 		default:
481 			return -EINVAL;
482 		}
483 		if (op->yes < 4 || op->yes > len + 4 || op->yes & 3)
484 			return -EINVAL;
485 		bc  += op->yes;
486 		len -= op->yes;
487 	}
488 	return len == 0 ? 0 : -EINVAL;
489 }
490 
491 static int inet_csk_diag_dump(struct sock *sk,
492 			      struct sk_buff *skb,
493 			      struct netlink_callback *cb,
494 			      struct inet_diag_req *r,
495 			      const struct nlattr *bc)
496 {
497 	if (bc != NULL) {
498 		struct inet_diag_entry entry;
499 		struct inet_sock *inet = inet_sk(sk);
500 
501 		entry.family = sk->sk_family;
502 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
503 		if (entry.family == AF_INET6) {
504 			struct ipv6_pinfo *np = inet6_sk(sk);
505 
506 			entry.saddr = np->rcv_saddr.s6_addr32;
507 			entry.daddr = np->daddr.s6_addr32;
508 		} else
509 #endif
510 		{
511 			entry.saddr = &inet->inet_rcv_saddr;
512 			entry.daddr = &inet->inet_daddr;
513 		}
514 		entry.sport = inet->inet_num;
515 		entry.dport = ntohs(inet->inet_dport);
516 		entry.userlocks = sk->sk_userlocks;
517 
518 		if (!inet_diag_bc_run(nla_data(bc), nla_len(bc), &entry))
519 			return 0;
520 	}
521 
522 	return inet_csk_diag_fill(sk, skb, r,
523 				  NETLINK_CB(cb->skb).pid,
524 				  cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh);
525 }
526 
527 static int inet_twsk_diag_dump(struct inet_timewait_sock *tw,
528 			       struct sk_buff *skb,
529 			       struct netlink_callback *cb,
530 			       struct inet_diag_req *r,
531 			       const struct nlattr *bc)
532 {
533 	if (bc != NULL) {
534 		struct inet_diag_entry entry;
535 
536 		entry.family = tw->tw_family;
537 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
538 		if (tw->tw_family == AF_INET6) {
539 			struct inet6_timewait_sock *tw6 =
540 						inet6_twsk((struct sock *)tw);
541 			entry.saddr = tw6->tw_v6_rcv_saddr.s6_addr32;
542 			entry.daddr = tw6->tw_v6_daddr.s6_addr32;
543 		} else
544 #endif
545 		{
546 			entry.saddr = &tw->tw_rcv_saddr;
547 			entry.daddr = &tw->tw_daddr;
548 		}
549 		entry.sport = tw->tw_num;
550 		entry.dport = ntohs(tw->tw_dport);
551 		entry.userlocks = 0;
552 
553 		if (!inet_diag_bc_run(nla_data(bc), nla_len(bc), &entry))
554 			return 0;
555 	}
556 
557 	return inet_twsk_diag_fill(tw, skb, r,
558 				   NETLINK_CB(cb->skb).pid,
559 				   cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh);
560 }
561 
562 static int inet_diag_fill_req(struct sk_buff *skb, struct sock *sk,
563 			      struct request_sock *req, u32 pid, u32 seq,
564 			      const struct nlmsghdr *unlh)
565 {
566 	const struct inet_request_sock *ireq = inet_rsk(req);
567 	struct inet_sock *inet = inet_sk(sk);
568 	unsigned char *b = skb_tail_pointer(skb);
569 	struct inet_diag_msg *r;
570 	struct nlmsghdr *nlh;
571 	long tmo;
572 
573 	nlh = NLMSG_PUT(skb, pid, seq, unlh->nlmsg_type, sizeof(*r));
574 	nlh->nlmsg_flags = NLM_F_MULTI;
575 	r = NLMSG_DATA(nlh);
576 
577 	r->idiag_family = sk->sk_family;
578 	r->idiag_state = TCP_SYN_RECV;
579 	r->idiag_timer = 1;
580 	r->idiag_retrans = req->retrans;
581 
582 	r->id.idiag_if = sk->sk_bound_dev_if;
583 	r->id.idiag_cookie[0] = (u32)(unsigned long)req;
584 	r->id.idiag_cookie[1] = (u32)(((unsigned long)req >> 31) >> 1);
585 
586 	tmo = req->expires - jiffies;
587 	if (tmo < 0)
588 		tmo = 0;
589 
590 	r->id.idiag_sport = inet->inet_sport;
591 	r->id.idiag_dport = ireq->rmt_port;
592 	r->id.idiag_src[0] = ireq->loc_addr;
593 	r->id.idiag_dst[0] = ireq->rmt_addr;
594 	r->idiag_expires = jiffies_to_msecs(tmo);
595 	r->idiag_rqueue = 0;
596 	r->idiag_wqueue = 0;
597 	r->idiag_uid = sock_i_uid(sk);
598 	r->idiag_inode = 0;
599 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
600 	if (r->idiag_family == AF_INET6) {
601 		*(struct in6_addr *)r->id.idiag_src = inet6_rsk(req)->loc_addr;
602 		*(struct in6_addr *)r->id.idiag_dst = inet6_rsk(req)->rmt_addr;
603 	}
604 #endif
605 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
606 
607 	return skb->len;
608 
609 nlmsg_failure:
610 	nlmsg_trim(skb, b);
611 	return -1;
612 }
613 
614 static int inet_diag_dump_reqs(struct sk_buff *skb, struct sock *sk,
615 			       struct netlink_callback *cb,
616 			       struct inet_diag_req *r,
617 			       const struct nlattr *bc)
618 {
619 	struct inet_diag_entry entry;
620 	struct inet_connection_sock *icsk = inet_csk(sk);
621 	struct listen_sock *lopt;
622 	struct inet_sock *inet = inet_sk(sk);
623 	int j, s_j;
624 	int reqnum, s_reqnum;
625 	int err = 0;
626 
627 	s_j = cb->args[3];
628 	s_reqnum = cb->args[4];
629 
630 	if (s_j > 0)
631 		s_j--;
632 
633 	entry.family = sk->sk_family;
634 
635 	read_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
636 
637 	lopt = icsk->icsk_accept_queue.listen_opt;
638 	if (!lopt || !lopt->qlen)
639 		goto out;
640 
641 	if (bc != NULL) {
642 		entry.sport = inet->inet_num;
643 		entry.userlocks = sk->sk_userlocks;
644 	}
645 
646 	for (j = s_j; j < lopt->nr_table_entries; j++) {
647 		struct request_sock *req, *head = lopt->syn_table[j];
648 
649 		reqnum = 0;
650 		for (req = head; req; reqnum++, req = req->dl_next) {
651 			struct inet_request_sock *ireq = inet_rsk(req);
652 
653 			if (reqnum < s_reqnum)
654 				continue;
655 			if (r->id.idiag_dport != ireq->rmt_port &&
656 			    r->id.idiag_dport)
657 				continue;
658 
659 			if (bc) {
660 				entry.saddr =
661 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
662 					(entry.family == AF_INET6) ?
663 					inet6_rsk(req)->loc_addr.s6_addr32 :
664 #endif
665 					&ireq->loc_addr;
666 				entry.daddr =
667 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
668 					(entry.family == AF_INET6) ?
669 					inet6_rsk(req)->rmt_addr.s6_addr32 :
670 #endif
671 					&ireq->rmt_addr;
672 				entry.dport = ntohs(ireq->rmt_port);
673 
674 				if (!inet_diag_bc_run(nla_data(bc),
675 						      nla_len(bc), &entry))
676 					continue;
677 			}
678 
679 			err = inet_diag_fill_req(skb, sk, req,
680 					       NETLINK_CB(cb->skb).pid,
681 					       cb->nlh->nlmsg_seq, cb->nlh);
682 			if (err < 0) {
683 				cb->args[3] = j + 1;
684 				cb->args[4] = reqnum;
685 				goto out;
686 			}
687 		}
688 
689 		s_reqnum = 0;
690 	}
691 
692 out:
693 	read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
694 
695 	return err;
696 }
697 
698 static int __inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb,
699 		struct inet_diag_req *r, struct nlattr *bc)
700 {
701 	int i, num;
702 	int s_i, s_num;
703 	const struct inet_diag_handler *handler;
704 	struct inet_hashinfo *hashinfo;
705 
706 	handler = inet_diag_lock_handler(r->sdiag_protocol);
707 	if (IS_ERR(handler))
708 		goto unlock;
709 
710 	hashinfo = handler->idiag_hashinfo;
711 
712 	s_i = cb->args[1];
713 	s_num = num = cb->args[2];
714 
715 	if (cb->args[0] == 0) {
716 		if (!(r->idiag_states & (TCPF_LISTEN | TCPF_SYN_RECV)))
717 			goto skip_listen_ht;
718 
719 		for (i = s_i; i < INET_LHTABLE_SIZE; i++) {
720 			struct sock *sk;
721 			struct hlist_nulls_node *node;
722 			struct inet_listen_hashbucket *ilb;
723 
724 			num = 0;
725 			ilb = &hashinfo->listening_hash[i];
726 			spin_lock_bh(&ilb->lock);
727 			sk_nulls_for_each(sk, node, &ilb->head) {
728 				struct inet_sock *inet = inet_sk(sk);
729 
730 				if (num < s_num) {
731 					num++;
732 					continue;
733 				}
734 
735 				if (r->sdiag_family != AF_UNSPEC &&
736 						sk->sk_family != r->sdiag_family)
737 					goto next_listen;
738 
739 				if (r->id.idiag_sport != inet->inet_sport &&
740 				    r->id.idiag_sport)
741 					goto next_listen;
742 
743 				if (!(r->idiag_states & TCPF_LISTEN) ||
744 				    r->id.idiag_dport ||
745 				    cb->args[3] > 0)
746 					goto syn_recv;
747 
748 				if (inet_csk_diag_dump(sk, skb, cb, r, bc) < 0) {
749 					spin_unlock_bh(&ilb->lock);
750 					goto done;
751 				}
752 
753 syn_recv:
754 				if (!(r->idiag_states & TCPF_SYN_RECV))
755 					goto next_listen;
756 
757 				if (inet_diag_dump_reqs(skb, sk, cb, r, bc) < 0) {
758 					spin_unlock_bh(&ilb->lock);
759 					goto done;
760 				}
761 
762 next_listen:
763 				cb->args[3] = 0;
764 				cb->args[4] = 0;
765 				++num;
766 			}
767 			spin_unlock_bh(&ilb->lock);
768 
769 			s_num = 0;
770 			cb->args[3] = 0;
771 			cb->args[4] = 0;
772 		}
773 skip_listen_ht:
774 		cb->args[0] = 1;
775 		s_i = num = s_num = 0;
776 	}
777 
778 	if (!(r->idiag_states & ~(TCPF_LISTEN | TCPF_SYN_RECV)))
779 		goto unlock;
780 
781 	for (i = s_i; i <= hashinfo->ehash_mask; i++) {
782 		struct inet_ehash_bucket *head = &hashinfo->ehash[i];
783 		spinlock_t *lock = inet_ehash_lockp(hashinfo, i);
784 		struct sock *sk;
785 		struct hlist_nulls_node *node;
786 
787 		num = 0;
788 
789 		if (hlist_nulls_empty(&head->chain) &&
790 			hlist_nulls_empty(&head->twchain))
791 			continue;
792 
793 		if (i > s_i)
794 			s_num = 0;
795 
796 		spin_lock_bh(lock);
797 		sk_nulls_for_each(sk, node, &head->chain) {
798 			struct inet_sock *inet = inet_sk(sk);
799 
800 			if (num < s_num)
801 				goto next_normal;
802 			if (!(r->idiag_states & (1 << sk->sk_state)))
803 				goto next_normal;
804 			if (r->sdiag_family != AF_UNSPEC &&
805 					sk->sk_family != r->sdiag_family)
806 				goto next_normal;
807 			if (r->id.idiag_sport != inet->inet_sport &&
808 			    r->id.idiag_sport)
809 				goto next_normal;
810 			if (r->id.idiag_dport != inet->inet_dport &&
811 			    r->id.idiag_dport)
812 				goto next_normal;
813 			if (inet_csk_diag_dump(sk, skb, cb, r, bc) < 0) {
814 				spin_unlock_bh(lock);
815 				goto done;
816 			}
817 next_normal:
818 			++num;
819 		}
820 
821 		if (r->idiag_states & TCPF_TIME_WAIT) {
822 			struct inet_timewait_sock *tw;
823 
824 			inet_twsk_for_each(tw, node,
825 				    &head->twchain) {
826 
827 				if (num < s_num)
828 					goto next_dying;
829 				if (r->sdiag_family != AF_UNSPEC &&
830 						tw->tw_family != r->sdiag_family)
831 					goto next_dying;
832 				if (r->id.idiag_sport != tw->tw_sport &&
833 				    r->id.idiag_sport)
834 					goto next_dying;
835 				if (r->id.idiag_dport != tw->tw_dport &&
836 				    r->id.idiag_dport)
837 					goto next_dying;
838 				if (inet_twsk_diag_dump(tw, skb, cb, r, bc) < 0) {
839 					spin_unlock_bh(lock);
840 					goto done;
841 				}
842 next_dying:
843 				++num;
844 			}
845 		}
846 		spin_unlock_bh(lock);
847 	}
848 
849 done:
850 	cb->args[1] = i;
851 	cb->args[2] = num;
852 unlock:
853 	inet_diag_unlock_handler(handler);
854 	return skb->len;
855 }
856 
857 static int inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
858 {
859 	struct nlattr *bc = NULL;
860 	int hdrlen = sizeof(struct inet_diag_req);
861 
862 	if (nlmsg_attrlen(cb->nlh, hdrlen))
863 		bc = nlmsg_find_attr(cb->nlh, hdrlen, INET_DIAG_REQ_BYTECODE);
864 
865 	return __inet_diag_dump(skb, cb, (struct inet_diag_req *)NLMSG_DATA(cb->nlh), bc);
866 }
867 
868 static inline int inet_diag_type2proto(int type)
869 {
870 	switch (type) {
871 	case TCPDIAG_GETSOCK:
872 		return IPPROTO_TCP;
873 	case DCCPDIAG_GETSOCK:
874 		return IPPROTO_DCCP;
875 	default:
876 		return 0;
877 	}
878 }
879 
880 static int inet_diag_dump_compat(struct sk_buff *skb, struct netlink_callback *cb)
881 {
882 	struct inet_diag_req_compat *rc = NLMSG_DATA(cb->nlh);
883 	struct inet_diag_req req;
884 	struct nlattr *bc = NULL;
885 	int hdrlen = sizeof(struct inet_diag_req_compat);
886 
887 	req.sdiag_family = AF_UNSPEC; /* compatibility */
888 	req.sdiag_protocol = inet_diag_type2proto(cb->nlh->nlmsg_type);
889 	req.idiag_ext = rc->idiag_ext;
890 	req.idiag_states = rc->idiag_states;
891 	req.id = rc->id;
892 
893 	if (nlmsg_attrlen(cb->nlh, hdrlen))
894 		bc = nlmsg_find_attr(cb->nlh, hdrlen, INET_DIAG_REQ_BYTECODE);
895 
896 	return __inet_diag_dump(skb, cb, &req, bc);
897 }
898 
899 static int inet_diag_get_exact_compat(struct sk_buff *in_skb,
900 			       const struct nlmsghdr *nlh)
901 {
902 	struct inet_diag_req_compat *rc = NLMSG_DATA(nlh);
903 	struct inet_diag_req req;
904 
905 	req.sdiag_family = rc->idiag_family;
906 	req.sdiag_protocol = inet_diag_type2proto(nlh->nlmsg_type);
907 	req.idiag_ext = rc->idiag_ext;
908 	req.idiag_states = rc->idiag_states;
909 	req.id = rc->id;
910 
911 	return inet_diag_get_exact(in_skb, nlh, &req);
912 }
913 
914 static int inet_diag_rcv_msg_compat(struct sk_buff *skb, struct nlmsghdr *nlh)
915 {
916 	int hdrlen = sizeof(struct inet_diag_req_compat);
917 
918 	if (nlh->nlmsg_type >= INET_DIAG_GETSOCK_MAX ||
919 	    nlmsg_len(nlh) < hdrlen)
920 		return -EINVAL;
921 
922 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
923 		if (nlmsg_attrlen(nlh, hdrlen)) {
924 			struct nlattr *attr;
925 
926 			attr = nlmsg_find_attr(nlh, hdrlen,
927 					       INET_DIAG_REQ_BYTECODE);
928 			if (attr == NULL ||
929 			    nla_len(attr) < sizeof(struct inet_diag_bc_op) ||
930 			    inet_diag_bc_audit(nla_data(attr), nla_len(attr)))
931 				return -EINVAL;
932 		}
933 
934 		return netlink_dump_start(sdiagnl, skb, nlh,
935 					  inet_diag_dump_compat, NULL, 0);
936 	}
937 
938 	return inet_diag_get_exact_compat(skb, nlh);
939 }
940 
941 static int inet_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h)
942 {
943 	int hdrlen = sizeof(struct inet_diag_req);
944 
945 	if (nlmsg_len(h) < hdrlen)
946 		return -EINVAL;
947 
948 	if (h->nlmsg_flags & NLM_F_DUMP) {
949 		if (nlmsg_attrlen(h, hdrlen)) {
950 			struct nlattr *attr;
951 			attr = nlmsg_find_attr(h, hdrlen,
952 					       INET_DIAG_REQ_BYTECODE);
953 			if (attr == NULL ||
954 			    nla_len(attr) < sizeof(struct inet_diag_bc_op) ||
955 			    inet_diag_bc_audit(nla_data(attr), nla_len(attr)))
956 				return -EINVAL;
957 		}
958 
959 		return netlink_dump_start(sdiagnl, skb, h,
960 					  inet_diag_dump, NULL, 0);
961 	}
962 
963 	return inet_diag_get_exact(skb, h, (struct inet_diag_req *)NLMSG_DATA(h));
964 }
965 
966 static struct sock_diag_handler inet_diag_handler = {
967 	.family = AF_INET,
968 	.dump = inet_diag_handler_dump,
969 };
970 
971 static struct sock_diag_handler inet6_diag_handler = {
972 	.family = AF_INET6,
973 	.dump = inet_diag_handler_dump,
974 };
975 
976 static struct sock_diag_handler *sock_diag_handlers[AF_MAX];
977 static DEFINE_MUTEX(sock_diag_table_mutex);
978 
979 int sock_diag_register(struct sock_diag_handler *hndl)
980 {
981 	int err = 0;
982 
983 	if (hndl->family > AF_MAX)
984 		return -EINVAL;
985 
986 	mutex_lock(&sock_diag_table_mutex);
987 	if (sock_diag_handlers[hndl->family])
988 		err = -EBUSY;
989 	else
990 		sock_diag_handlers[hndl->family] = hndl;
991 	mutex_unlock(&sock_diag_table_mutex);
992 
993 	return err;
994 }
995 
996 void sock_diag_unregister(struct sock_diag_handler *hnld)
997 {
998 	int family = hnld->family;
999 
1000 	if (family > AF_MAX)
1001 		return;
1002 
1003 	mutex_lock(&sock_diag_table_mutex);
1004 	BUG_ON(sock_diag_handlers[family] != hnld);
1005 	sock_diag_handlers[family] = NULL;
1006 	mutex_unlock(&sock_diag_table_mutex);
1007 }
1008 
1009 static inline struct sock_diag_handler *sock_diag_lock_handler(int family)
1010 {
1011 	mutex_lock(&sock_diag_table_mutex);
1012 	return sock_diag_handlers[family];
1013 }
1014 
1015 static inline void sock_diag_unlock_handler(struct sock_diag_handler *h)
1016 {
1017 	mutex_unlock(&sock_diag_table_mutex);
1018 }
1019 
1020 static int __sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
1021 {
1022 	int err;
1023 	struct sock_diag_req *req = NLMSG_DATA(nlh);
1024 	struct sock_diag_handler *hndl;
1025 
1026 	if (nlmsg_len(nlh) < sizeof(*req))
1027 		return -EINVAL;
1028 
1029 	hndl = sock_diag_lock_handler(req->sdiag_family);
1030 	if (hndl == NULL)
1031 		err = -ENOENT;
1032 	else
1033 		err = hndl->dump(skb, nlh);
1034 	sock_diag_unlock_handler(hndl);
1035 
1036 	return err;
1037 }
1038 
1039 static int sock_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
1040 {
1041 	switch (nlh->nlmsg_type) {
1042 	case TCPDIAG_GETSOCK:
1043 	case DCCPDIAG_GETSOCK:
1044 		return inet_diag_rcv_msg_compat(skb, nlh);
1045 	case SOCK_DIAG_BY_FAMILY:
1046 		return __sock_diag_rcv_msg(skb, nlh);
1047 	default:
1048 		return -EINVAL;
1049 	}
1050 }
1051 
1052 static DEFINE_MUTEX(sock_diag_mutex);
1053 
1054 static void sock_diag_rcv(struct sk_buff *skb)
1055 {
1056 	mutex_lock(&sock_diag_mutex);
1057 	netlink_rcv_skb(skb, &sock_diag_rcv_msg);
1058 	mutex_unlock(&sock_diag_mutex);
1059 }
1060 
1061 int inet_diag_register(const struct inet_diag_handler *h)
1062 {
1063 	const __u16 type = h->idiag_type;
1064 	int err = -EINVAL;
1065 
1066 	if (type >= IPPROTO_MAX)
1067 		goto out;
1068 
1069 	mutex_lock(&inet_diag_table_mutex);
1070 	err = -EEXIST;
1071 	if (inet_diag_table[type] == NULL) {
1072 		inet_diag_table[type] = h;
1073 		err = 0;
1074 	}
1075 	mutex_unlock(&inet_diag_table_mutex);
1076 out:
1077 	return err;
1078 }
1079 EXPORT_SYMBOL_GPL(inet_diag_register);
1080 
1081 void inet_diag_unregister(const struct inet_diag_handler *h)
1082 {
1083 	const __u16 type = h->idiag_type;
1084 
1085 	if (type >= IPPROTO_MAX)
1086 		return;
1087 
1088 	mutex_lock(&inet_diag_table_mutex);
1089 	inet_diag_table[type] = NULL;
1090 	mutex_unlock(&inet_diag_table_mutex);
1091 }
1092 EXPORT_SYMBOL_GPL(inet_diag_unregister);
1093 
1094 static int __init inet_diag_init(void)
1095 {
1096 	const int inet_diag_table_size = (IPPROTO_MAX *
1097 					  sizeof(struct inet_diag_handler *));
1098 	int err = -ENOMEM;
1099 
1100 	inet_diag_table = kzalloc(inet_diag_table_size, GFP_KERNEL);
1101 	if (!inet_diag_table)
1102 		goto out;
1103 
1104 	sdiagnl = netlink_kernel_create(&init_net, NETLINK_SOCK_DIAG, 0,
1105 					sock_diag_rcv, NULL, THIS_MODULE);
1106 	if (sdiagnl == NULL)
1107 		goto out_free_table;
1108 
1109 	err = sock_diag_register(&inet_diag_handler);
1110 	if (err)
1111 		goto out_free_nl;
1112 
1113 	err = sock_diag_register(&inet6_diag_handler);
1114 	if (err)
1115 		goto out_free_inet;
1116 
1117 out:
1118 	return err;
1119 
1120 out_free_inet:
1121 	sock_diag_unregister(&inet_diag_handler);
1122 out_free_nl:
1123 	netlink_kernel_release(sdiagnl);
1124 out_free_table:
1125 	kfree(inet_diag_table);
1126 	goto out;
1127 }
1128 
1129 static void __exit inet_diag_exit(void)
1130 {
1131 	sock_diag_unregister(&inet6_diag_handler);
1132 	sock_diag_unregister(&inet_diag_handler);
1133 	netlink_kernel_release(sdiagnl);
1134 	kfree(inet_diag_table);
1135 }
1136 
1137 module_init(inet_diag_init);
1138 module_exit(inet_diag_exit);
1139 MODULE_LICENSE("GPL");
1140 MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_SOCK_DIAG);
1141