xref: /openbmc/linux/net/ipv4/inet_diag.c (revision b8f3ab42)
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 
37 static const struct inet_diag_handler **inet_diag_table;
38 
39 struct inet_diag_entry {
40 	__be32 *saddr;
41 	__be32 *daddr;
42 	u16 sport;
43 	u16 dport;
44 	u16 family;
45 	u16 userlocks;
46 };
47 
48 static struct sock *idiagnl;
49 
50 #define INET_DIAG_PUT(skb, attrtype, attrlen) \
51 	RTA_DATA(__RTA_PUT(skb, attrtype, attrlen))
52 
53 static DEFINE_MUTEX(inet_diag_table_mutex);
54 
55 static const struct inet_diag_handler *inet_diag_lock_handler(int type)
56 {
57 	if (!inet_diag_table[type])
58 		request_module("net-pf-%d-proto-%d-type-%d", PF_NETLINK,
59 			       NETLINK_INET_DIAG, type);
60 
61 	mutex_lock(&inet_diag_table_mutex);
62 	if (!inet_diag_table[type])
63 		return ERR_PTR(-ENOENT);
64 
65 	return inet_diag_table[type];
66 }
67 
68 static inline void inet_diag_unlock_handler(
69 	const struct inet_diag_handler *handler)
70 {
71 	mutex_unlock(&inet_diag_table_mutex);
72 }
73 
74 static int inet_csk_diag_fill(struct sock *sk,
75 			      struct sk_buff *skb,
76 			      int ext, u32 pid, u32 seq, u16 nlmsg_flags,
77 			      const struct nlmsghdr *unlh)
78 {
79 	const struct inet_sock *inet = inet_sk(sk);
80 	const struct inet_connection_sock *icsk = inet_csk(sk);
81 	struct inet_diag_msg *r;
82 	struct nlmsghdr  *nlh;
83 	void *info = NULL;
84 	struct inet_diag_meminfo  *minfo = NULL;
85 	unsigned char	 *b = skb_tail_pointer(skb);
86 	const struct inet_diag_handler *handler;
87 
88 	handler = inet_diag_table[unlh->nlmsg_type];
89 	BUG_ON(handler == NULL);
90 
91 	nlh = NLMSG_PUT(skb, pid, seq, unlh->nlmsg_type, sizeof(*r));
92 	nlh->nlmsg_flags = nlmsg_flags;
93 
94 	r = NLMSG_DATA(nlh);
95 	BUG_ON(sk->sk_state == TCP_TIME_WAIT);
96 
97 	if (ext & (1 << (INET_DIAG_MEMINFO - 1)))
98 		minfo = INET_DIAG_PUT(skb, INET_DIAG_MEMINFO, sizeof(*minfo));
99 
100 	if (ext & (1 << (INET_DIAG_INFO - 1)))
101 		info = INET_DIAG_PUT(skb, INET_DIAG_INFO,
102 				     handler->idiag_info_size);
103 
104 	if ((ext & (1 << (INET_DIAG_CONG - 1))) && icsk->icsk_ca_ops) {
105 		const size_t len = strlen(icsk->icsk_ca_ops->name);
106 
107 		strcpy(INET_DIAG_PUT(skb, INET_DIAG_CONG, len + 1),
108 		       icsk->icsk_ca_ops->name);
109 	}
110 
111 	r->idiag_family = sk->sk_family;
112 	r->idiag_state = sk->sk_state;
113 	r->idiag_timer = 0;
114 	r->idiag_retrans = 0;
115 
116 	r->id.idiag_if = sk->sk_bound_dev_if;
117 	r->id.idiag_cookie[0] = (u32)(unsigned long)sk;
118 	r->id.idiag_cookie[1] = (u32)(((unsigned long)sk >> 31) >> 1);
119 
120 	r->id.idiag_sport = inet->inet_sport;
121 	r->id.idiag_dport = inet->inet_dport;
122 	r->id.idiag_src[0] = inet->inet_rcv_saddr;
123 	r->id.idiag_dst[0] = inet->inet_daddr;
124 
125 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
126 	if (r->idiag_family == AF_INET6) {
127 		struct ipv6_pinfo *np = inet6_sk(sk);
128 
129 		ipv6_addr_copy((struct in6_addr *)r->id.idiag_src,
130 			       &np->rcv_saddr);
131 		ipv6_addr_copy((struct in6_addr *)r->id.idiag_dst,
132 			       &np->daddr);
133 	}
134 #endif
135 
136 #define EXPIRES_IN_MS(tmo)  DIV_ROUND_UP((tmo - jiffies) * 1000, HZ)
137 
138 	if (icsk->icsk_pending == ICSK_TIME_RETRANS) {
139 		r->idiag_timer = 1;
140 		r->idiag_retrans = icsk->icsk_retransmits;
141 		r->idiag_expires = EXPIRES_IN_MS(icsk->icsk_timeout);
142 	} else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
143 		r->idiag_timer = 4;
144 		r->idiag_retrans = icsk->icsk_probes_out;
145 		r->idiag_expires = EXPIRES_IN_MS(icsk->icsk_timeout);
146 	} else if (timer_pending(&sk->sk_timer)) {
147 		r->idiag_timer = 2;
148 		r->idiag_retrans = icsk->icsk_probes_out;
149 		r->idiag_expires = EXPIRES_IN_MS(sk->sk_timer.expires);
150 	} else {
151 		r->idiag_timer = 0;
152 		r->idiag_expires = 0;
153 	}
154 #undef EXPIRES_IN_MS
155 
156 	r->idiag_uid = sock_i_uid(sk);
157 	r->idiag_inode = sock_i_ino(sk);
158 
159 	if (minfo) {
160 		minfo->idiag_rmem = sk_rmem_alloc_get(sk);
161 		minfo->idiag_wmem = sk->sk_wmem_queued;
162 		minfo->idiag_fmem = sk->sk_forward_alloc;
163 		minfo->idiag_tmem = sk_wmem_alloc_get(sk);
164 	}
165 
166 	handler->idiag_get_info(sk, r, info);
167 
168 	if (sk->sk_state < TCP_TIME_WAIT &&
169 	    icsk->icsk_ca_ops && icsk->icsk_ca_ops->get_info)
170 		icsk->icsk_ca_ops->get_info(sk, ext, skb);
171 
172 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
173 	return skb->len;
174 
175 rtattr_failure:
176 nlmsg_failure:
177 	nlmsg_trim(skb, b);
178 	return -EMSGSIZE;
179 }
180 
181 static int inet_twsk_diag_fill(struct inet_timewait_sock *tw,
182 			       struct sk_buff *skb, int ext, u32 pid,
183 			       u32 seq, u16 nlmsg_flags,
184 			       const struct nlmsghdr *unlh)
185 {
186 	long tmo;
187 	struct inet_diag_msg *r;
188 	const unsigned char *previous_tail = skb_tail_pointer(skb);
189 	struct nlmsghdr *nlh = NLMSG_PUT(skb, pid, seq,
190 					 unlh->nlmsg_type, sizeof(*r));
191 
192 	r = NLMSG_DATA(nlh);
193 	BUG_ON(tw->tw_state != TCP_TIME_WAIT);
194 
195 	nlh->nlmsg_flags = nlmsg_flags;
196 
197 	tmo = tw->tw_ttd - jiffies;
198 	if (tmo < 0)
199 		tmo = 0;
200 
201 	r->idiag_family	      = tw->tw_family;
202 	r->idiag_retrans      = 0;
203 	r->id.idiag_if	      = tw->tw_bound_dev_if;
204 	r->id.idiag_cookie[0] = (u32)(unsigned long)tw;
205 	r->id.idiag_cookie[1] = (u32)(((unsigned long)tw >> 31) >> 1);
206 	r->id.idiag_sport     = tw->tw_sport;
207 	r->id.idiag_dport     = tw->tw_dport;
208 	r->id.idiag_src[0]    = tw->tw_rcv_saddr;
209 	r->id.idiag_dst[0]    = tw->tw_daddr;
210 	r->idiag_state	      = tw->tw_substate;
211 	r->idiag_timer	      = 3;
212 	r->idiag_expires      = DIV_ROUND_UP(tmo * 1000, HZ);
213 	r->idiag_rqueue	      = 0;
214 	r->idiag_wqueue	      = 0;
215 	r->idiag_uid	      = 0;
216 	r->idiag_inode	      = 0;
217 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
218 	if (tw->tw_family == AF_INET6) {
219 		const struct inet6_timewait_sock *tw6 =
220 						inet6_twsk((struct sock *)tw);
221 
222 		ipv6_addr_copy((struct in6_addr *)r->id.idiag_src,
223 			       &tw6->tw_v6_rcv_saddr);
224 		ipv6_addr_copy((struct in6_addr *)r->id.idiag_dst,
225 			       &tw6->tw_v6_daddr);
226 	}
227 #endif
228 	nlh->nlmsg_len = skb_tail_pointer(skb) - previous_tail;
229 	return skb->len;
230 nlmsg_failure:
231 	nlmsg_trim(skb, previous_tail);
232 	return -EMSGSIZE;
233 }
234 
235 static int sk_diag_fill(struct sock *sk, struct sk_buff *skb,
236 			int ext, u32 pid, u32 seq, u16 nlmsg_flags,
237 			const struct nlmsghdr *unlh)
238 {
239 	if (sk->sk_state == TCP_TIME_WAIT)
240 		return inet_twsk_diag_fill((struct inet_timewait_sock *)sk,
241 					   skb, ext, pid, seq, nlmsg_flags,
242 					   unlh);
243 	return inet_csk_diag_fill(sk, skb, ext, pid, seq, nlmsg_flags, unlh);
244 }
245 
246 static int inet_diag_get_exact(struct sk_buff *in_skb,
247 			       const struct nlmsghdr *nlh)
248 {
249 	int err;
250 	struct sock *sk;
251 	struct inet_diag_req *req = NLMSG_DATA(nlh);
252 	struct sk_buff *rep;
253 	struct inet_hashinfo *hashinfo;
254 	const struct inet_diag_handler *handler;
255 
256 	handler = inet_diag_lock_handler(nlh->nlmsg_type);
257 	if (IS_ERR(handler)) {
258 		err = PTR_ERR(handler);
259 		goto unlock;
260 	}
261 
262 	hashinfo = handler->idiag_hashinfo;
263 	err = -EINVAL;
264 
265 	if (req->idiag_family == AF_INET) {
266 		sk = inet_lookup(&init_net, hashinfo, req->id.idiag_dst[0],
267 				 req->id.idiag_dport, req->id.idiag_src[0],
268 				 req->id.idiag_sport, req->id.idiag_if);
269 	}
270 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
271 	else if (req->idiag_family == AF_INET6) {
272 		sk = inet6_lookup(&init_net, hashinfo,
273 				  (struct in6_addr *)req->id.idiag_dst,
274 				  req->id.idiag_dport,
275 				  (struct in6_addr *)req->id.idiag_src,
276 				  req->id.idiag_sport,
277 				  req->id.idiag_if);
278 	}
279 #endif
280 	else {
281 		goto unlock;
282 	}
283 
284 	err = -ENOENT;
285 	if (sk == NULL)
286 		goto unlock;
287 
288 	err = -ESTALE;
289 	if ((req->id.idiag_cookie[0] != INET_DIAG_NOCOOKIE ||
290 	     req->id.idiag_cookie[1] != INET_DIAG_NOCOOKIE) &&
291 	    ((u32)(unsigned long)sk != req->id.idiag_cookie[0] ||
292 	     (u32)((((unsigned long)sk) >> 31) >> 1) != req->id.idiag_cookie[1]))
293 		goto out;
294 
295 	err = -ENOMEM;
296 	rep = alloc_skb(NLMSG_SPACE((sizeof(struct inet_diag_msg) +
297 				     sizeof(struct inet_diag_meminfo) +
298 				     handler->idiag_info_size + 64)),
299 			GFP_KERNEL);
300 	if (!rep)
301 		goto out;
302 
303 	err = sk_diag_fill(sk, rep, req->idiag_ext,
304 			   NETLINK_CB(in_skb).pid,
305 			   nlh->nlmsg_seq, 0, nlh);
306 	if (err < 0) {
307 		WARN_ON(err == -EMSGSIZE);
308 		kfree_skb(rep);
309 		goto out;
310 	}
311 	err = netlink_unicast(idiagnl, rep, NETLINK_CB(in_skb).pid,
312 			      MSG_DONTWAIT);
313 	if (err > 0)
314 		err = 0;
315 
316 out:
317 	if (sk) {
318 		if (sk->sk_state == TCP_TIME_WAIT)
319 			inet_twsk_put((struct inet_timewait_sock *)sk);
320 		else
321 			sock_put(sk);
322 	}
323 unlock:
324 	inet_diag_unlock_handler(handler);
325 	return err;
326 }
327 
328 static int bitstring_match(const __be32 *a1, const __be32 *a2, int bits)
329 {
330 	int words = bits >> 5;
331 
332 	bits &= 0x1f;
333 
334 	if (words) {
335 		if (memcmp(a1, a2, words << 2))
336 			return 0;
337 	}
338 	if (bits) {
339 		__be32 w1, w2;
340 		__be32 mask;
341 
342 		w1 = a1[words];
343 		w2 = a2[words];
344 
345 		mask = htonl((0xffffffff) << (32 - bits));
346 
347 		if ((w1 ^ w2) & mask)
348 			return 0;
349 	}
350 
351 	return 1;
352 }
353 
354 
355 static int inet_diag_bc_run(const void *bc, int len,
356 			    const struct inet_diag_entry *entry)
357 {
358 	while (len > 0) {
359 		int yes = 1;
360 		const struct inet_diag_bc_op *op = bc;
361 
362 		switch (op->code) {
363 		case INET_DIAG_BC_NOP:
364 			break;
365 		case INET_DIAG_BC_JMP:
366 			yes = 0;
367 			break;
368 		case INET_DIAG_BC_S_GE:
369 			yes = entry->sport >= op[1].no;
370 			break;
371 		case INET_DIAG_BC_S_LE:
372 			yes = entry->sport <= op[1].no;
373 			break;
374 		case INET_DIAG_BC_D_GE:
375 			yes = entry->dport >= op[1].no;
376 			break;
377 		case INET_DIAG_BC_D_LE:
378 			yes = entry->dport <= op[1].no;
379 			break;
380 		case INET_DIAG_BC_AUTO:
381 			yes = !(entry->userlocks & SOCK_BINDPORT_LOCK);
382 			break;
383 		case INET_DIAG_BC_S_COND:
384 		case INET_DIAG_BC_D_COND: {
385 			struct inet_diag_hostcond *cond;
386 			__be32 *addr;
387 
388 			cond = (struct inet_diag_hostcond *)(op + 1);
389 			if (cond->port != -1 &&
390 			    cond->port != (op->code == INET_DIAG_BC_S_COND ?
391 					     entry->sport : entry->dport)) {
392 				yes = 0;
393 				break;
394 			}
395 
396 			if (cond->prefix_len == 0)
397 				break;
398 
399 			if (op->code == INET_DIAG_BC_S_COND)
400 				addr = entry->saddr;
401 			else
402 				addr = entry->daddr;
403 
404 			if (bitstring_match(addr, cond->addr,
405 					    cond->prefix_len))
406 				break;
407 			if (entry->family == AF_INET6 &&
408 			    cond->family == AF_INET) {
409 				if (addr[0] == 0 && addr[1] == 0 &&
410 				    addr[2] == htonl(0xffff) &&
411 				    bitstring_match(addr + 3, cond->addr,
412 						    cond->prefix_len))
413 					break;
414 			}
415 			yes = 0;
416 			break;
417 		}
418 		}
419 
420 		if (yes) {
421 			len -= op->yes;
422 			bc += op->yes;
423 		} else {
424 			len -= op->no;
425 			bc += op->no;
426 		}
427 	}
428 	return len == 0;
429 }
430 
431 static int valid_cc(const void *bc, int len, int cc)
432 {
433 	while (len >= 0) {
434 		const struct inet_diag_bc_op *op = bc;
435 
436 		if (cc > len)
437 			return 0;
438 		if (cc == len)
439 			return 1;
440 		if (op->yes < 4)
441 			return 0;
442 		len -= op->yes;
443 		bc  += op->yes;
444 	}
445 	return 0;
446 }
447 
448 static int inet_diag_bc_audit(const void *bytecode, int bytecode_len)
449 {
450 	const unsigned char *bc = bytecode;
451 	int  len = bytecode_len;
452 
453 	while (len > 0) {
454 		struct inet_diag_bc_op *op = (struct inet_diag_bc_op *)bc;
455 
456 //printk("BC: %d %d %d {%d} / %d\n", op->code, op->yes, op->no, op[1].no, len);
457 		switch (op->code) {
458 		case INET_DIAG_BC_AUTO:
459 		case INET_DIAG_BC_S_COND:
460 		case INET_DIAG_BC_D_COND:
461 		case INET_DIAG_BC_S_GE:
462 		case INET_DIAG_BC_S_LE:
463 		case INET_DIAG_BC_D_GE:
464 		case INET_DIAG_BC_D_LE:
465 			if (op->yes < 4 || op->yes > len + 4)
466 				return -EINVAL;
467 		case INET_DIAG_BC_JMP:
468 			if (op->no < 4 || op->no > len + 4)
469 				return -EINVAL;
470 			if (op->no < len &&
471 			    !valid_cc(bytecode, bytecode_len, len - op->no))
472 				return -EINVAL;
473 			break;
474 		case INET_DIAG_BC_NOP:
475 			if (op->yes < 4 || op->yes > len + 4)
476 				return -EINVAL;
477 			break;
478 		default:
479 			return -EINVAL;
480 		}
481 		bc  += op->yes;
482 		len -= op->yes;
483 	}
484 	return len == 0 ? 0 : -EINVAL;
485 }
486 
487 static int inet_csk_diag_dump(struct sock *sk,
488 			      struct sk_buff *skb,
489 			      struct netlink_callback *cb)
490 {
491 	struct inet_diag_req *r = NLMSG_DATA(cb->nlh);
492 
493 	if (nlmsg_attrlen(cb->nlh, sizeof(*r))) {
494 		struct inet_diag_entry entry;
495 		const struct nlattr *bc = nlmsg_find_attr(cb->nlh,
496 							  sizeof(*r),
497 							  INET_DIAG_REQ_BYTECODE);
498 		struct inet_sock *inet = inet_sk(sk);
499 
500 		entry.family = sk->sk_family;
501 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
502 		if (entry.family == AF_INET6) {
503 			struct ipv6_pinfo *np = inet6_sk(sk);
504 
505 			entry.saddr = np->rcv_saddr.s6_addr32;
506 			entry.daddr = np->daddr.s6_addr32;
507 		} else
508 #endif
509 		{
510 			entry.saddr = &inet->inet_rcv_saddr;
511 			entry.daddr = &inet->inet_daddr;
512 		}
513 		entry.sport = inet->inet_num;
514 		entry.dport = ntohs(inet->inet_dport);
515 		entry.userlocks = sk->sk_userlocks;
516 
517 		if (!inet_diag_bc_run(nla_data(bc), nla_len(bc), &entry))
518 			return 0;
519 	}
520 
521 	return inet_csk_diag_fill(sk, skb, r->idiag_ext,
522 				  NETLINK_CB(cb->skb).pid,
523 				  cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh);
524 }
525 
526 static int inet_twsk_diag_dump(struct inet_timewait_sock *tw,
527 			       struct sk_buff *skb,
528 			       struct netlink_callback *cb)
529 {
530 	struct inet_diag_req *r = NLMSG_DATA(cb->nlh);
531 
532 	if (nlmsg_attrlen(cb->nlh, sizeof(*r))) {
533 		struct inet_diag_entry entry;
534 		const struct nlattr *bc = nlmsg_find_attr(cb->nlh,
535 							  sizeof(*r),
536 							  INET_DIAG_REQ_BYTECODE);
537 
538 		entry.family = tw->tw_family;
539 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
540 		if (tw->tw_family == AF_INET6) {
541 			struct inet6_timewait_sock *tw6 =
542 						inet6_twsk((struct sock *)tw);
543 			entry.saddr = tw6->tw_v6_rcv_saddr.s6_addr32;
544 			entry.daddr = tw6->tw_v6_daddr.s6_addr32;
545 		} else
546 #endif
547 		{
548 			entry.saddr = &tw->tw_rcv_saddr;
549 			entry.daddr = &tw->tw_daddr;
550 		}
551 		entry.sport = tw->tw_num;
552 		entry.dport = ntohs(tw->tw_dport);
553 		entry.userlocks = 0;
554 
555 		if (!inet_diag_bc_run(nla_data(bc), nla_len(bc), &entry))
556 			return 0;
557 	}
558 
559 	return inet_twsk_diag_fill(tw, skb, r->idiag_ext,
560 				   NETLINK_CB(cb->skb).pid,
561 				   cb->nlh->nlmsg_seq, NLM_F_MULTI, cb->nlh);
562 }
563 
564 static int inet_diag_fill_req(struct sk_buff *skb, struct sock *sk,
565 			      struct request_sock *req, u32 pid, u32 seq,
566 			      const struct nlmsghdr *unlh)
567 {
568 	const struct inet_request_sock *ireq = inet_rsk(req);
569 	struct inet_sock *inet = inet_sk(sk);
570 	unsigned char *b = skb_tail_pointer(skb);
571 	struct inet_diag_msg *r;
572 	struct nlmsghdr *nlh;
573 	long tmo;
574 
575 	nlh = NLMSG_PUT(skb, pid, seq, unlh->nlmsg_type, sizeof(*r));
576 	nlh->nlmsg_flags = NLM_F_MULTI;
577 	r = NLMSG_DATA(nlh);
578 
579 	r->idiag_family = sk->sk_family;
580 	r->idiag_state = TCP_SYN_RECV;
581 	r->idiag_timer = 1;
582 	r->idiag_retrans = req->retrans;
583 
584 	r->id.idiag_if = sk->sk_bound_dev_if;
585 	r->id.idiag_cookie[0] = (u32)(unsigned long)req;
586 	r->id.idiag_cookie[1] = (u32)(((unsigned long)req >> 31) >> 1);
587 
588 	tmo = req->expires - jiffies;
589 	if (tmo < 0)
590 		tmo = 0;
591 
592 	r->id.idiag_sport = inet->inet_sport;
593 	r->id.idiag_dport = ireq->rmt_port;
594 	r->id.idiag_src[0] = ireq->loc_addr;
595 	r->id.idiag_dst[0] = ireq->rmt_addr;
596 	r->idiag_expires = jiffies_to_msecs(tmo);
597 	r->idiag_rqueue = 0;
598 	r->idiag_wqueue = 0;
599 	r->idiag_uid = sock_i_uid(sk);
600 	r->idiag_inode = 0;
601 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
602 	if (r->idiag_family == AF_INET6) {
603 		ipv6_addr_copy((struct in6_addr *)r->id.idiag_src,
604 			       &inet6_rsk(req)->loc_addr);
605 		ipv6_addr_copy((struct in6_addr *)r->id.idiag_dst,
606 			       &inet6_rsk(req)->rmt_addr);
607 	}
608 #endif
609 	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
610 
611 	return skb->len;
612 
613 nlmsg_failure:
614 	nlmsg_trim(skb, b);
615 	return -1;
616 }
617 
618 static int inet_diag_dump_reqs(struct sk_buff *skb, struct sock *sk,
619 			       struct netlink_callback *cb)
620 {
621 	struct inet_diag_entry entry;
622 	struct inet_diag_req *r = NLMSG_DATA(cb->nlh);
623 	struct inet_connection_sock *icsk = inet_csk(sk);
624 	struct listen_sock *lopt;
625 	const struct nlattr *bc = NULL;
626 	struct inet_sock *inet = inet_sk(sk);
627 	int j, s_j;
628 	int reqnum, s_reqnum;
629 	int err = 0;
630 
631 	s_j = cb->args[3];
632 	s_reqnum = cb->args[4];
633 
634 	if (s_j > 0)
635 		s_j--;
636 
637 	entry.family = sk->sk_family;
638 
639 	read_lock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
640 
641 	lopt = icsk->icsk_accept_queue.listen_opt;
642 	if (!lopt || !lopt->qlen)
643 		goto out;
644 
645 	if (nlmsg_attrlen(cb->nlh, sizeof(*r))) {
646 		bc = nlmsg_find_attr(cb->nlh, sizeof(*r),
647 				     INET_DIAG_REQ_BYTECODE);
648 		entry.sport = inet->inet_num;
649 		entry.userlocks = sk->sk_userlocks;
650 	}
651 
652 	for (j = s_j; j < lopt->nr_table_entries; j++) {
653 		struct request_sock *req, *head = lopt->syn_table[j];
654 
655 		reqnum = 0;
656 		for (req = head; req; reqnum++, req = req->dl_next) {
657 			struct inet_request_sock *ireq = inet_rsk(req);
658 
659 			if (reqnum < s_reqnum)
660 				continue;
661 			if (r->id.idiag_dport != ireq->rmt_port &&
662 			    r->id.idiag_dport)
663 				continue;
664 
665 			if (bc) {
666 				entry.saddr =
667 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
668 					(entry.family == AF_INET6) ?
669 					inet6_rsk(req)->loc_addr.s6_addr32 :
670 #endif
671 					&ireq->loc_addr;
672 				entry.daddr =
673 #if defined(CONFIG_IPV6) || defined (CONFIG_IPV6_MODULE)
674 					(entry.family == AF_INET6) ?
675 					inet6_rsk(req)->rmt_addr.s6_addr32 :
676 #endif
677 					&ireq->rmt_addr;
678 				entry.dport = ntohs(ireq->rmt_port);
679 
680 				if (!inet_diag_bc_run(nla_data(bc),
681 						      nla_len(bc), &entry))
682 					continue;
683 			}
684 
685 			err = inet_diag_fill_req(skb, sk, req,
686 					       NETLINK_CB(cb->skb).pid,
687 					       cb->nlh->nlmsg_seq, cb->nlh);
688 			if (err < 0) {
689 				cb->args[3] = j + 1;
690 				cb->args[4] = reqnum;
691 				goto out;
692 			}
693 		}
694 
695 		s_reqnum = 0;
696 	}
697 
698 out:
699 	read_unlock_bh(&icsk->icsk_accept_queue.syn_wait_lock);
700 
701 	return err;
702 }
703 
704 static int inet_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
705 {
706 	int i, num;
707 	int s_i, s_num;
708 	struct inet_diag_req *r = NLMSG_DATA(cb->nlh);
709 	const struct inet_diag_handler *handler;
710 	struct inet_hashinfo *hashinfo;
711 
712 	handler = inet_diag_lock_handler(cb->nlh->nlmsg_type);
713 	if (IS_ERR(handler))
714 		goto unlock;
715 
716 	hashinfo = handler->idiag_hashinfo;
717 
718 	s_i = cb->args[1];
719 	s_num = num = cb->args[2];
720 
721 	if (cb->args[0] == 0) {
722 		if (!(r->idiag_states & (TCPF_LISTEN | TCPF_SYN_RECV)))
723 			goto skip_listen_ht;
724 
725 		for (i = s_i; i < INET_LHTABLE_SIZE; i++) {
726 			struct sock *sk;
727 			struct hlist_nulls_node *node;
728 			struct inet_listen_hashbucket *ilb;
729 
730 			num = 0;
731 			ilb = &hashinfo->listening_hash[i];
732 			spin_lock_bh(&ilb->lock);
733 			sk_nulls_for_each(sk, node, &ilb->head) {
734 				struct inet_sock *inet = inet_sk(sk);
735 
736 				if (num < s_num) {
737 					num++;
738 					continue;
739 				}
740 
741 				if (r->id.idiag_sport != inet->inet_sport &&
742 				    r->id.idiag_sport)
743 					goto next_listen;
744 
745 				if (!(r->idiag_states & TCPF_LISTEN) ||
746 				    r->id.idiag_dport ||
747 				    cb->args[3] > 0)
748 					goto syn_recv;
749 
750 				if (inet_csk_diag_dump(sk, skb, cb) < 0) {
751 					spin_unlock_bh(&ilb->lock);
752 					goto done;
753 				}
754 
755 syn_recv:
756 				if (!(r->idiag_states & TCPF_SYN_RECV))
757 					goto next_listen;
758 
759 				if (inet_diag_dump_reqs(skb, sk, cb) < 0) {
760 					spin_unlock_bh(&ilb->lock);
761 					goto done;
762 				}
763 
764 next_listen:
765 				cb->args[3] = 0;
766 				cb->args[4] = 0;
767 				++num;
768 			}
769 			spin_unlock_bh(&ilb->lock);
770 
771 			s_num = 0;
772 			cb->args[3] = 0;
773 			cb->args[4] = 0;
774 		}
775 skip_listen_ht:
776 		cb->args[0] = 1;
777 		s_i = num = s_num = 0;
778 	}
779 
780 	if (!(r->idiag_states & ~(TCPF_LISTEN | TCPF_SYN_RECV)))
781 		goto unlock;
782 
783 	for (i = s_i; i <= hashinfo->ehash_mask; i++) {
784 		struct inet_ehash_bucket *head = &hashinfo->ehash[i];
785 		spinlock_t *lock = inet_ehash_lockp(hashinfo, i);
786 		struct sock *sk;
787 		struct hlist_nulls_node *node;
788 
789 		num = 0;
790 
791 		if (hlist_nulls_empty(&head->chain) &&
792 			hlist_nulls_empty(&head->twchain))
793 			continue;
794 
795 		if (i > s_i)
796 			s_num = 0;
797 
798 		spin_lock_bh(lock);
799 		sk_nulls_for_each(sk, node, &head->chain) {
800 			struct inet_sock *inet = inet_sk(sk);
801 
802 			if (num < s_num)
803 				goto next_normal;
804 			if (!(r->idiag_states & (1 << sk->sk_state)))
805 				goto next_normal;
806 			if (r->id.idiag_sport != inet->inet_sport &&
807 			    r->id.idiag_sport)
808 				goto next_normal;
809 			if (r->id.idiag_dport != inet->inet_dport &&
810 			    r->id.idiag_dport)
811 				goto next_normal;
812 			if (inet_csk_diag_dump(sk, skb, cb) < 0) {
813 				spin_unlock_bh(lock);
814 				goto done;
815 			}
816 next_normal:
817 			++num;
818 		}
819 
820 		if (r->idiag_states & TCPF_TIME_WAIT) {
821 			struct inet_timewait_sock *tw;
822 
823 			inet_twsk_for_each(tw, node,
824 				    &head->twchain) {
825 
826 				if (num < s_num)
827 					goto next_dying;
828 				if (r->id.idiag_sport != tw->tw_sport &&
829 				    r->id.idiag_sport)
830 					goto next_dying;
831 				if (r->id.idiag_dport != tw->tw_dport &&
832 				    r->id.idiag_dport)
833 					goto next_dying;
834 				if (inet_twsk_diag_dump(tw, skb, cb) < 0) {
835 					spin_unlock_bh(lock);
836 					goto done;
837 				}
838 next_dying:
839 				++num;
840 			}
841 		}
842 		spin_unlock_bh(lock);
843 	}
844 
845 done:
846 	cb->args[1] = i;
847 	cb->args[2] = num;
848 unlock:
849 	inet_diag_unlock_handler(handler);
850 	return skb->len;
851 }
852 
853 static int inet_diag_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
854 {
855 	int hdrlen = sizeof(struct inet_diag_req);
856 
857 	if (nlh->nlmsg_type >= INET_DIAG_GETSOCK_MAX ||
858 	    nlmsg_len(nlh) < hdrlen)
859 		return -EINVAL;
860 
861 	if (nlh->nlmsg_flags & NLM_F_DUMP) {
862 		if (nlmsg_attrlen(nlh, hdrlen)) {
863 			struct nlattr *attr;
864 
865 			attr = nlmsg_find_attr(nlh, hdrlen,
866 					       INET_DIAG_REQ_BYTECODE);
867 			if (attr == NULL ||
868 			    nla_len(attr) < sizeof(struct inet_diag_bc_op) ||
869 			    inet_diag_bc_audit(nla_data(attr), nla_len(attr)))
870 				return -EINVAL;
871 		}
872 
873 		return netlink_dump_start(idiagnl, skb, nlh,
874 					  inet_diag_dump, NULL);
875 	}
876 
877 	return inet_diag_get_exact(skb, nlh);
878 }
879 
880 static DEFINE_MUTEX(inet_diag_mutex);
881 
882 static void inet_diag_rcv(struct sk_buff *skb)
883 {
884 	mutex_lock(&inet_diag_mutex);
885 	netlink_rcv_skb(skb, &inet_diag_rcv_msg);
886 	mutex_unlock(&inet_diag_mutex);
887 }
888 
889 int inet_diag_register(const struct inet_diag_handler *h)
890 {
891 	const __u16 type = h->idiag_type;
892 	int err = -EINVAL;
893 
894 	if (type >= INET_DIAG_GETSOCK_MAX)
895 		goto out;
896 
897 	mutex_lock(&inet_diag_table_mutex);
898 	err = -EEXIST;
899 	if (inet_diag_table[type] == NULL) {
900 		inet_diag_table[type] = h;
901 		err = 0;
902 	}
903 	mutex_unlock(&inet_diag_table_mutex);
904 out:
905 	return err;
906 }
907 EXPORT_SYMBOL_GPL(inet_diag_register);
908 
909 void inet_diag_unregister(const struct inet_diag_handler *h)
910 {
911 	const __u16 type = h->idiag_type;
912 
913 	if (type >= INET_DIAG_GETSOCK_MAX)
914 		return;
915 
916 	mutex_lock(&inet_diag_table_mutex);
917 	inet_diag_table[type] = NULL;
918 	mutex_unlock(&inet_diag_table_mutex);
919 }
920 EXPORT_SYMBOL_GPL(inet_diag_unregister);
921 
922 static int __init inet_diag_init(void)
923 {
924 	const int inet_diag_table_size = (INET_DIAG_GETSOCK_MAX *
925 					  sizeof(struct inet_diag_handler *));
926 	int err = -ENOMEM;
927 
928 	inet_diag_table = kzalloc(inet_diag_table_size, GFP_KERNEL);
929 	if (!inet_diag_table)
930 		goto out;
931 
932 	idiagnl = netlink_kernel_create(&init_net, NETLINK_INET_DIAG, 0,
933 					inet_diag_rcv, NULL, THIS_MODULE);
934 	if (idiagnl == NULL)
935 		goto out_free_table;
936 	err = 0;
937 out:
938 	return err;
939 out_free_table:
940 	kfree(inet_diag_table);
941 	goto out;
942 }
943 
944 static void __exit inet_diag_exit(void)
945 {
946 	netlink_kernel_release(idiagnl);
947 	kfree(inet_diag_table);
948 }
949 
950 module_init(inet_diag_init);
951 module_exit(inet_diag_exit);
952 MODULE_LICENSE("GPL");
953 MODULE_ALIAS_NET_PF_PROTO(PF_NETLINK, NETLINK_INET_DIAG);
954