keysock.c revision 180385 
1/*	$FreeBSD: head/sys/netipsec/keysock.c 180385 2008-07-09 15:48:16Z rwatson $	*/
2/*	$KAME: keysock.c,v 1.25 2001/08/13 20:07:41 itojun Exp $	*/
3
4/*-
5 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#include "opt_ipsec.h"
34
35/* This code has derived from sys/net/rtsock.c on FreeBSD2.2.5 */
36
37#include <sys/types.h>
38#include <sys/param.h>
39#include <sys/domain.h>
40#include <sys/errno.h>
41#include <sys/kernel.h>
42#include <sys/lock.h>
43#include <sys/malloc.h>
44#include <sys/mbuf.h>
45#include <sys/mutex.h>
46#include <sys/priv.h>
47#include <sys/protosw.h>
48#include <sys/signalvar.h>
49#include <sys/socket.h>
50#include <sys/socketvar.h>
51#include <sys/sysctl.h>
52#include <sys/systm.h>
53
54#include <net/raw_cb.h>
55#include <net/route.h>
56
57#include <net/pfkeyv2.h>
58#include <netipsec/key.h>
59#include <netipsec/keysock.h>
60#include <netipsec/key_debug.h>
61
62#include <machine/stdarg.h>
63
64struct key_cb {
65	int key_count;
66	int any_count;
67};
68static struct key_cb key_cb;
69
70static struct sockaddr key_src = { 2, PF_KEY, };
71
72static int key_sendup0 __P((struct rawcb *, struct mbuf *, int));
73
74struct pfkeystat pfkeystat;
75
76/*
77 * key_output()
78 */
79int
80key_output(struct mbuf *m, struct socket *so)
81{
82	struct sadb_msg *msg;
83	int len, error = 0;
84
85	if (m == 0)
86		panic("%s: NULL pointer was passed.\n", __func__);
87
88	pfkeystat.out_total++;
89	pfkeystat.out_bytes += m->m_pkthdr.len;
90
91	len = m->m_pkthdr.len;
92	if (len < sizeof(struct sadb_msg)) {
93		pfkeystat.out_tooshort++;
94		error = EINVAL;
95		goto end;
96	}
97
98	if (m->m_len < sizeof(struct sadb_msg)) {
99		if ((m = m_pullup(m, sizeof(struct sadb_msg))) == 0) {
100			pfkeystat.out_nomem++;
101			error = ENOBUFS;
102			goto end;
103		}
104	}
105
106	M_ASSERTPKTHDR(m);
107
108	KEYDEBUG(KEYDEBUG_KEY_DUMP, kdebug_mbuf(m));
109
110	msg = mtod(m, struct sadb_msg *);
111	pfkeystat.out_msgtype[msg->sadb_msg_type]++;
112	if (len != PFKEY_UNUNIT64(msg->sadb_msg_len)) {
113		pfkeystat.out_invlen++;
114		error = EINVAL;
115		goto end;
116	}
117
118	error = key_parse(m, so);
119	m = NULL;
120end:
121	if (m)
122		m_freem(m);
123	return error;
124}
125
126/*
127 * send message to the socket.
128 */
129static int
130key_sendup0(rp, m, promisc)
131	struct rawcb *rp;
132	struct mbuf *m;
133	int promisc;
134{
135	int error;
136
137	if (promisc) {
138		struct sadb_msg *pmsg;
139
140		M_PREPEND(m, sizeof(struct sadb_msg), M_DONTWAIT);
141		if (m && m->m_len < sizeof(struct sadb_msg))
142			m = m_pullup(m, sizeof(struct sadb_msg));
143		if (!m) {
144			pfkeystat.in_nomem++;
145			m_freem(m);
146			return ENOBUFS;
147		}
148		m->m_pkthdr.len += sizeof(*pmsg);
149
150		pmsg = mtod(m, struct sadb_msg *);
151		bzero(pmsg, sizeof(*pmsg));
152		pmsg->sadb_msg_version = PF_KEY_V2;
153		pmsg->sadb_msg_type = SADB_X_PROMISC;
154		pmsg->sadb_msg_len = PFKEY_UNIT64(m->m_pkthdr.len);
155		/* pid and seq? */
156
157		pfkeystat.in_msgtype[pmsg->sadb_msg_type]++;
158	}
159
160	if (!sbappendaddr(&rp->rcb_socket->so_rcv, (struct sockaddr *)&key_src,
161	    m, NULL)) {
162		pfkeystat.in_nomem++;
163		m_freem(m);
164		error = ENOBUFS;
165	} else
166		error = 0;
167	sorwakeup(rp->rcb_socket);
168	return error;
169}
170
171/* XXX this interface should be obsoleted. */
172int
173key_sendup(so, msg, len, target)
174	struct socket *so;
175	struct sadb_msg *msg;
176	u_int len;
177	int target;	/*target of the resulting message*/
178{
179	struct mbuf *m, *n, *mprev;
180	int tlen;
181
182	/* sanity check */
183	if (so == 0 || msg == 0)
184		panic("%s: NULL pointer was passed.\n", __func__);
185
186	KEYDEBUG(KEYDEBUG_KEY_DUMP,
187		printf("%s: \n", __func__);
188		kdebug_sadb(msg));
189
190	/*
191	 * we increment statistics here, just in case we have ENOBUFS
192	 * in this function.
193	 */
194	pfkeystat.in_total++;
195	pfkeystat.in_bytes += len;
196	pfkeystat.in_msgtype[msg->sadb_msg_type]++;
197
198	/*
199	 * Get mbuf chain whenever possible (not clusters),
200	 * to save socket buffer.  We'll be generating many SADB_ACQUIRE
201	 * messages to listening key sockets.  If we simply allocate clusters,
202	 * sbappendaddr() will raise ENOBUFS due to too little sbspace().
203	 * sbspace() computes # of actual data bytes AND mbuf region.
204	 *
205	 * TODO: SADB_ACQUIRE filters should be implemented.
206	 */
207	tlen = len;
208	m = mprev = NULL;
209	while (tlen > 0) {
210		if (tlen == len) {
211			MGETHDR(n, M_DONTWAIT, MT_DATA);
212			if (n == NULL) {
213				pfkeystat.in_nomem++;
214				return ENOBUFS;
215			}
216			n->m_len = MHLEN;
217		} else {
218			MGET(n, M_DONTWAIT, MT_DATA);
219			if (n == NULL) {
220				pfkeystat.in_nomem++;
221				return ENOBUFS;
222			}
223			n->m_len = MLEN;
224		}
225		if (tlen >= MCLBYTES) {	/*XXX better threshold? */
226			MCLGET(n, M_DONTWAIT);
227			if ((n->m_flags & M_EXT) == 0) {
228				m_free(n);
229				m_freem(m);
230				pfkeystat.in_nomem++;
231				return ENOBUFS;
232			}
233			n->m_len = MCLBYTES;
234		}
235
236		if (tlen < n->m_len)
237			n->m_len = tlen;
238		n->m_next = NULL;
239		if (m == NULL)
240			m = mprev = n;
241		else {
242			mprev->m_next = n;
243			mprev = n;
244		}
245		tlen -= n->m_len;
246		n = NULL;
247	}
248	m->m_pkthdr.len = len;
249	m->m_pkthdr.rcvif = NULL;
250	m_copyback(m, 0, len, (caddr_t)msg);
251
252	/* avoid duplicated statistics */
253	pfkeystat.in_total--;
254	pfkeystat.in_bytes -= len;
255	pfkeystat.in_msgtype[msg->sadb_msg_type]--;
256
257	return key_sendup_mbuf(so, m, target);
258}
259
260/* so can be NULL if target != KEY_SENDUP_ONE */
261int
262key_sendup_mbuf(so, m, target)
263	struct socket *so;
264	struct mbuf *m;
265	int target;
266{
267	struct mbuf *n;
268	struct keycb *kp;
269	int sendup;
270	struct rawcb *rp;
271	int error = 0;
272
273	if (m == NULL)
274		panic("key_sendup_mbuf: NULL pointer was passed.\n");
275	if (so == NULL && target == KEY_SENDUP_ONE)
276		panic("%s: NULL pointer was passed.\n", __func__);
277
278	pfkeystat.in_total++;
279	pfkeystat.in_bytes += m->m_pkthdr.len;
280	if (m->m_len < sizeof(struct sadb_msg)) {
281		m = m_pullup(m, sizeof(struct sadb_msg));
282		if (m == NULL) {
283			pfkeystat.in_nomem++;
284			return ENOBUFS;
285		}
286	}
287	if (m->m_len >= sizeof(struct sadb_msg)) {
288		struct sadb_msg *msg;
289		msg = mtod(m, struct sadb_msg *);
290		pfkeystat.in_msgtype[msg->sadb_msg_type]++;
291	}
292	mtx_lock(&rawcb_mtx);
293	LIST_FOREACH(rp, &rawcb_list, list)
294	{
295		if (rp->rcb_proto.sp_family != PF_KEY)
296			continue;
297		if (rp->rcb_proto.sp_protocol
298		 && rp->rcb_proto.sp_protocol != PF_KEY_V2) {
299			continue;
300		}
301
302		kp = (struct keycb *)rp;
303
304		/*
305		 * If you are in promiscuous mode, and when you get broadcasted
306		 * reply, you'll get two PF_KEY messages.
307		 * (based on pf_key@inner.net message on 14 Oct 1998)
308		 */
309		if (((struct keycb *)rp)->kp_promisc) {
310			if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
311				(void)key_sendup0(rp, n, 1);
312				n = NULL;
313			}
314		}
315
316		/* the exact target will be processed later */
317		if (so && sotorawcb(so) == rp)
318			continue;
319
320		sendup = 0;
321		switch (target) {
322		case KEY_SENDUP_ONE:
323			/* the statement has no effect */
324			if (so && sotorawcb(so) == rp)
325				sendup++;
326			break;
327		case KEY_SENDUP_ALL:
328			sendup++;
329			break;
330		case KEY_SENDUP_REGISTERED:
331			if (kp->kp_registered)
332				sendup++;
333			break;
334		}
335		pfkeystat.in_msgtarget[target]++;
336
337		if (!sendup)
338			continue;
339
340		if ((n = m_copy(m, 0, (int)M_COPYALL)) == NULL) {
341			m_freem(m);
342			pfkeystat.in_nomem++;
343			mtx_unlock(&rawcb_mtx);
344			return ENOBUFS;
345		}
346
347		if ((error = key_sendup0(rp, n, 0)) != 0) {
348			m_freem(m);
349			mtx_unlock(&rawcb_mtx);
350			return error;
351		}
352
353		n = NULL;
354	}
355
356	if (so) {
357		error = key_sendup0(sotorawcb(so), m, 0);
358		m = NULL;
359	} else {
360		error = 0;
361		m_freem(m);
362	}
363	mtx_unlock(&rawcb_mtx);
364	return error;
365}
366
367/*
368 * key_abort()
369 * derived from net/rtsock.c:rts_abort()
370 */
371static void
372key_abort(struct socket *so)
373{
374	raw_usrreqs.pru_abort(so);
375}
376
377/*
378 * key_attach()
379 * derived from net/rtsock.c:rts_attach()
380 */
381static int
382key_attach(struct socket *so, int proto, struct thread *td)
383{
384	struct keycb *kp;
385	int error;
386
387	KASSERT(so->so_pcb == NULL, ("key_attach: so_pcb != NULL"));
388
389	if (td != NULL) {
390		error = priv_check(td, PRIV_NET_RAW);
391		if (error)
392			return error;
393	}
394
395	/* XXX */
396	MALLOC(kp, struct keycb *, sizeof *kp, M_PCB, M_WAITOK | M_ZERO);
397	if (kp == 0)
398		return ENOBUFS;
399
400	so->so_pcb = (caddr_t)kp;
401	error = raw_attach(so, proto);
402	kp = (struct keycb *)sotorawcb(so);
403	if (error) {
404		free(kp, M_PCB);
405		so->so_pcb = (caddr_t) 0;
406		return error;
407	}
408
409	kp->kp_promisc = kp->kp_registered = 0;
410
411	if (kp->kp_raw.rcb_proto.sp_protocol == PF_KEY) /* XXX: AF_KEY */
412		key_cb.key_count++;
413	key_cb.any_count++;
414	soisconnected(so);
415	so->so_options |= SO_USELOOPBACK;
416
417	return 0;
418}
419
420/*
421 * key_bind()
422 * derived from net/rtsock.c:rts_bind()
423 */
424static int
425key_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
426{
427  return EINVAL;
428}
429
430/*
431 * key_close()
432 * derived from net/rtsock.c:rts_close().
433 */
434static void
435key_close(struct socket *so)
436{
437
438	raw_usrreqs.pru_close(so);
439}
440
441/*
442 * key_connect()
443 * derived from net/rtsock.c:rts_connect()
444 */
445static int
446key_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
447{
448	return EINVAL;
449}
450
451/*
452 * key_detach()
453 * derived from net/rtsock.c:rts_detach()
454 */
455static void
456key_detach(struct socket *so)
457{
458	struct keycb *kp = (struct keycb *)sotorawcb(so);
459
460	KASSERT(kp != NULL, ("key_detach: kp == NULL"));
461	if (kp->kp_raw.rcb_proto.sp_protocol
462	    == PF_KEY) /* XXX: AF_KEY */
463		key_cb.key_count--;
464	key_cb.any_count--;
465
466	key_freereg(so);
467	raw_usrreqs.pru_detach(so);
468}
469
470/*
471 * key_disconnect()
472 * derived from net/rtsock.c:key_disconnect()
473 */
474static int
475key_disconnect(struct socket *so)
476{
477	return(raw_usrreqs.pru_disconnect(so));
478}
479
480/*
481 * key_peeraddr()
482 * derived from net/rtsock.c:rts_peeraddr()
483 */
484static int
485key_peeraddr(struct socket *so, struct sockaddr **nam)
486{
487	return(raw_usrreqs.pru_peeraddr(so, nam));
488}
489
490/*
491 * key_send()
492 * derived from net/rtsock.c:rts_send()
493 */
494static int
495key_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
496	 struct mbuf *control, struct thread *td)
497{
498	return(raw_usrreqs.pru_send(so, flags, m, nam, control, td));
499}
500
501/*
502 * key_shutdown()
503 * derived from net/rtsock.c:rts_shutdown()
504 */
505static int
506key_shutdown(struct socket *so)
507{
508	return(raw_usrreqs.pru_shutdown(so));
509}
510
511/*
512 * key_sockaddr()
513 * derived from net/rtsock.c:rts_sockaddr()
514 */
515static int
516key_sockaddr(struct socket *so, struct sockaddr **nam)
517{
518	return(raw_usrreqs.pru_sockaddr(so, nam));
519}
520
521struct pr_usrreqs key_usrreqs = {
522	.pru_abort =		key_abort,
523	.pru_attach =		key_attach,
524	.pru_bind =		key_bind,
525	.pru_connect =		key_connect,
526	.pru_detach =		key_detach,
527	.pru_disconnect =	key_disconnect,
528	.pru_peeraddr =		key_peeraddr,
529	.pru_send =		key_send,
530	.pru_shutdown =		key_shutdown,
531	.pru_sockaddr =		key_sockaddr,
532	.pru_close =		key_close,
533};
534
535/* sysctl */
536SYSCTL_NODE(_net, PF_KEY, key, CTLFLAG_RW, 0, "Key Family");
537
538/*
539 * Definitions of protocols supported in the KEY domain.
540 */
541
542extern struct domain keydomain;
543
544struct protosw keysw[] = {
545{
546	.pr_type =		SOCK_RAW,
547	.pr_domain =		&keydomain,
548	.pr_protocol =		PF_KEY_V2,
549	.pr_flags =		PR_ATOMIC|PR_ADDR,
550	.pr_output =		key_output,
551	.pr_ctlinput =		raw_ctlinput,
552	.pr_init =		raw_init,
553	.pr_usrreqs =		&key_usrreqs
554}
555};
556
557static void
558key_init0(void)
559{
560	bzero((caddr_t)&key_cb, sizeof(key_cb));
561	key_init();
562}
563
564struct domain keydomain = {
565	.dom_family =		PF_KEY,
566	.dom_name =		"key",
567	.dom_init =		key_init0,
568	.dom_protosw =		keysw,
569	.dom_protoswNPROTOSW =	&keysw[sizeof(keysw)/sizeof(keysw[0])]
570};
571
572DOMAIN_SET(key);
573