keysock.c revision 181803 
1/*	$FreeBSD: head/sys/netipsec/keysock.c 181803 2008-08-17 23:27:27Z bz $	*/
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#include <sys/vimage.h>
54
55#include <net/raw_cb.h>
56#include <net/route.h>
57
58#include <net/pfkeyv2.h>
59#include <netipsec/key.h>
60#include <netipsec/keysock.h>
61#include <netipsec/key_debug.h>
62
63#include <machine/stdarg.h>
64
65struct key_cb {
66	int key_count;
67	int any_count;
68};
69static struct key_cb key_cb;
70
71static struct sockaddr key_src = { 2, PF_KEY, };
72
73static int key_sendup0 __P((struct rawcb *, struct mbuf *, int));
74
75struct pfkeystat pfkeystat;
76
77/*
78 * key_output()
79 */
80int
81key_output(struct mbuf *m, struct socket *so)
82{
83	struct sadb_msg *msg;
84	int len, error = 0;
85
86	if (m == 0)
87		panic("%s: NULL pointer was passed.\n", __func__);
88
89	V_pfkeystat.out_total++;
90	V_pfkeystat.out_bytes += m->m_pkthdr.len;
91
92	len = m->m_pkthdr.len;
93	if (len < sizeof(struct sadb_msg)) {
94		V_pfkeystat.out_tooshort++;
95		error = EINVAL;
96		goto end;
97	}
98
99	if (m->m_len < sizeof(struct sadb_msg)) {
100		if ((m = m_pullup(m, sizeof(struct sadb_msg))) == 0) {
101			V_pfkeystat.out_nomem++;
102			error = ENOBUFS;
103			goto end;
104		}
105	}
106
107	M_ASSERTPKTHDR(m);
108
109	KEYDEBUG(KEYDEBUG_KEY_DUMP, kdebug_mbuf(m));
110
111	msg = mtod(m, struct sadb_msg *);
112	V_pfkeystat.out_msgtype[msg->sadb_msg_type]++;
113	if (len != PFKEY_UNUNIT64(msg->sadb_msg_len)) {
114		V_pfkeystat.out_invlen++;
115		error = EINVAL;
116		goto end;
117	}
118
119	error = key_parse(m, so);
120	m = NULL;
121end:
122	if (m)
123		m_freem(m);
124	return error;
125}
126
127/*
128 * send message to the socket.
129 */
130static int
131key_sendup0(rp, m, promisc)
132	struct rawcb *rp;
133	struct mbuf *m;
134	int promisc;
135{
136	int error;
137
138	if (promisc) {
139		struct sadb_msg *pmsg;
140
141		M_PREPEND(m, sizeof(struct sadb_msg), M_DONTWAIT);
142		if (m && m->m_len < sizeof(struct sadb_msg))
143			m = m_pullup(m, sizeof(struct sadb_msg));
144		if (!m) {
145			V_pfkeystat.in_nomem++;
146			m_freem(m);
147			return ENOBUFS;
148		}
149		m->m_pkthdr.len += sizeof(*pmsg);
150
151		pmsg = mtod(m, struct sadb_msg *);
152		bzero(pmsg, sizeof(*pmsg));
153		pmsg->sadb_msg_version = PF_KEY_V2;
154		pmsg->sadb_msg_type = SADB_X_PROMISC;
155		pmsg->sadb_msg_len = PFKEY_UNIT64(m->m_pkthdr.len);
156		/* pid and seq? */
157
158		V_pfkeystat.in_msgtype[pmsg->sadb_msg_type]++;
159	}
160
161	if (!sbappendaddr(&rp->rcb_socket->so_rcv, (struct sockaddr *)&V_key_src,
162	    m, NULL)) {
163		V_pfkeystat.in_nomem++;
164		m_freem(m);
165		error = ENOBUFS;
166	} else
167		error = 0;
168	sorwakeup(rp->rcb_socket);
169	return error;
170}
171
172/* XXX this interface should be obsoleted. */
173int
174key_sendup(so, msg, len, target)
175	struct socket *so;
176	struct sadb_msg *msg;
177	u_int len;
178	int target;	/*target of the resulting message*/
179{
180	struct mbuf *m, *n, *mprev;
181	int tlen;
182
183	/* sanity check */
184	if (so == 0 || msg == 0)
185		panic("%s: NULL pointer was passed.\n", __func__);
186
187	KEYDEBUG(KEYDEBUG_KEY_DUMP,
188		printf("%s: \n", __func__);
189		kdebug_sadb(msg));
190
191	/*
192	 * we increment statistics here, just in case we have ENOBUFS
193	 * in this function.
194	 */
195	V_pfkeystat.in_total++;
196	V_pfkeystat.in_bytes += len;
197	V_pfkeystat.in_msgtype[msg->sadb_msg_type]++;
198
199	/*
200	 * Get mbuf chain whenever possible (not clusters),
201	 * to save socket buffer.  We'll be generating many SADB_ACQUIRE
202	 * messages to listening key sockets.  If we simply allocate clusters,
203	 * sbappendaddr() will raise ENOBUFS due to too little sbspace().
204	 * sbspace() computes # of actual data bytes AND mbuf region.
205	 *
206	 * TODO: SADB_ACQUIRE filters should be implemented.
207	 */
208	tlen = len;
209	m = mprev = NULL;
210	while (tlen > 0) {
211		if (tlen == len) {
212			MGETHDR(n, M_DONTWAIT, MT_DATA);
213			if (n == NULL) {
214				V_pfkeystat.in_nomem++;
215				return ENOBUFS;
216			}
217			n->m_len = MHLEN;
218		} else {
219			MGET(n, M_DONTWAIT, MT_DATA);
220			if (n == NULL) {
221				V_pfkeystat.in_nomem++;
222				return ENOBUFS;
223			}
224			n->m_len = MLEN;
225		}
226		if (tlen >= MCLBYTES) {	/*XXX better threshold? */
227			MCLGET(n, M_DONTWAIT);
228			if ((n->m_flags & M_EXT) == 0) {
229				m_free(n);
230				m_freem(m);
231				V_pfkeystat.in_nomem++;
232				return ENOBUFS;
233			}
234			n->m_len = MCLBYTES;
235		}
236
237		if (tlen < n->m_len)
238			n->m_len = tlen;
239		n->m_next = NULL;
240		if (m == NULL)
241			m = mprev = n;
242		else {
243			mprev->m_next = n;
244			mprev = n;
245		}
246		tlen -= n->m_len;
247		n = NULL;
248	}
249	m->m_pkthdr.len = len;
250	m->m_pkthdr.rcvif = NULL;
251	m_copyback(m, 0, len, (caddr_t)msg);
252
253	/* avoid duplicated statistics */
254	V_pfkeystat.in_total--;
255	V_pfkeystat.in_bytes -= len;
256	V_pfkeystat.in_msgtype[msg->sadb_msg_type]--;
257
258	return key_sendup_mbuf(so, m, target);
259}
260
261/* so can be NULL if target != KEY_SENDUP_ONE */
262int
263key_sendup_mbuf(so, m, target)
264	struct socket *so;
265	struct mbuf *m;
266	int target;
267{
268	struct mbuf *n;
269	struct keycb *kp;
270	int sendup;
271	struct rawcb *rp;
272	int error = 0;
273
274	if (m == NULL)
275		panic("key_sendup_mbuf: NULL pointer was passed.\n");
276	if (so == NULL && target == KEY_SENDUP_ONE)
277		panic("%s: NULL pointer was passed.\n", __func__);
278
279	V_pfkeystat.in_total++;
280	V_pfkeystat.in_bytes += m->m_pkthdr.len;
281	if (m->m_len < sizeof(struct sadb_msg)) {
282		m = m_pullup(m, sizeof(struct sadb_msg));
283		if (m == NULL) {
284			V_pfkeystat.in_nomem++;
285			return ENOBUFS;
286		}
287	}
288	if (m->m_len >= sizeof(struct sadb_msg)) {
289		struct sadb_msg *msg;
290		msg = mtod(m, struct sadb_msg *);
291		V_pfkeystat.in_msgtype[msg->sadb_msg_type]++;
292	}
293	mtx_lock(&rawcb_mtx);
294	LIST_FOREACH(rp, &V_rawcb_list, list)
295	{
296		if (rp->rcb_proto.sp_family != PF_KEY)
297			continue;
298		if (rp->rcb_proto.sp_protocol
299		 && rp->rcb_proto.sp_protocol != PF_KEY_V2) {
300			continue;
301		}
302
303		kp = (struct keycb *)rp;
304
305		/*
306		 * If you are in promiscuous mode, and when you get broadcasted
307		 * reply, you'll get two PF_KEY messages.
308		 * (based on pf_key@inner.net message on 14 Oct 1998)
309		 */
310		if (((struct keycb *)rp)->kp_promisc) {
311			if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
312				(void)key_sendup0(rp, n, 1);
313				n = NULL;
314			}
315		}
316
317		/* the exact target will be processed later */
318		if (so && sotorawcb(so) == rp)
319			continue;
320
321		sendup = 0;
322		switch (target) {
323		case KEY_SENDUP_ONE:
324			/* the statement has no effect */
325			if (so && sotorawcb(so) == rp)
326				sendup++;
327			break;
328		case KEY_SENDUP_ALL:
329			sendup++;
330			break;
331		case KEY_SENDUP_REGISTERED:
332			if (kp->kp_registered)
333				sendup++;
334			break;
335		}
336		V_pfkeystat.in_msgtarget[target]++;
337
338		if (!sendup)
339			continue;
340
341		if ((n = m_copy(m, 0, (int)M_COPYALL)) == NULL) {
342			m_freem(m);
343			V_pfkeystat.in_nomem++;
344			mtx_unlock(&rawcb_mtx);
345			return ENOBUFS;
346		}
347
348		if ((error = key_sendup0(rp, n, 0)) != 0) {
349			m_freem(m);
350			mtx_unlock(&rawcb_mtx);
351			return error;
352		}
353
354		n = NULL;
355	}
356
357	if (so) {
358		error = key_sendup0(sotorawcb(so), m, 0);
359		m = NULL;
360	} else {
361		error = 0;
362		m_freem(m);
363	}
364	mtx_unlock(&rawcb_mtx);
365	return error;
366}
367
368/*
369 * key_abort()
370 * derived from net/rtsock.c:rts_abort()
371 */
372static void
373key_abort(struct socket *so)
374{
375	raw_usrreqs.pru_abort(so);
376}
377
378/*
379 * key_attach()
380 * derived from net/rtsock.c:rts_attach()
381 */
382static int
383key_attach(struct socket *so, int proto, struct thread *td)
384{
385	struct keycb *kp;
386	int error;
387
388	KASSERT(so->so_pcb == NULL, ("key_attach: so_pcb != NULL"));
389
390	if (td != NULL) {
391		error = priv_check(td, PRIV_NET_RAW);
392		if (error)
393			return error;
394	}
395
396	/* XXX */
397	MALLOC(kp, struct keycb *, sizeof *kp, M_PCB, M_WAITOK | M_ZERO);
398	if (kp == 0)
399		return ENOBUFS;
400
401	so->so_pcb = (caddr_t)kp;
402	error = raw_attach(so, proto);
403	kp = (struct keycb *)sotorawcb(so);
404	if (error) {
405		free(kp, M_PCB);
406		so->so_pcb = (caddr_t) 0;
407		return error;
408	}
409
410	kp->kp_promisc = kp->kp_registered = 0;
411
412	if (kp->kp_raw.rcb_proto.sp_protocol == PF_KEY) /* XXX: AF_KEY */
413		V_key_cb.key_count++;
414	V_key_cb.any_count++;
415	soisconnected(so);
416	so->so_options |= SO_USELOOPBACK;
417
418	return 0;
419}
420
421/*
422 * key_bind()
423 * derived from net/rtsock.c:rts_bind()
424 */
425static int
426key_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
427{
428  return EINVAL;
429}
430
431/*
432 * key_close()
433 * derived from net/rtsock.c:rts_close().
434 */
435static void
436key_close(struct socket *so)
437{
438
439	raw_usrreqs.pru_close(so);
440}
441
442/*
443 * key_connect()
444 * derived from net/rtsock.c:rts_connect()
445 */
446static int
447key_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
448{
449	return EINVAL;
450}
451
452/*
453 * key_detach()
454 * derived from net/rtsock.c:rts_detach()
455 */
456static void
457key_detach(struct socket *so)
458{
459	struct keycb *kp = (struct keycb *)sotorawcb(so);
460
461	KASSERT(kp != NULL, ("key_detach: kp == NULL"));
462	if (kp->kp_raw.rcb_proto.sp_protocol
463	    == PF_KEY) /* XXX: AF_KEY */
464		V_key_cb.key_count--;
465	V_key_cb.any_count--;
466
467	key_freereg(so);
468	raw_usrreqs.pru_detach(so);
469}
470
471/*
472 * key_disconnect()
473 * derived from net/rtsock.c:key_disconnect()
474 */
475static int
476key_disconnect(struct socket *so)
477{
478	return(raw_usrreqs.pru_disconnect(so));
479}
480
481/*
482 * key_peeraddr()
483 * derived from net/rtsock.c:rts_peeraddr()
484 */
485static int
486key_peeraddr(struct socket *so, struct sockaddr **nam)
487{
488	return(raw_usrreqs.pru_peeraddr(so, nam));
489}
490
491/*
492 * key_send()
493 * derived from net/rtsock.c:rts_send()
494 */
495static int
496key_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
497	 struct mbuf *control, struct thread *td)
498{
499	return(raw_usrreqs.pru_send(so, flags, m, nam, control, td));
500}
501
502/*
503 * key_shutdown()
504 * derived from net/rtsock.c:rts_shutdown()
505 */
506static int
507key_shutdown(struct socket *so)
508{
509	return(raw_usrreqs.pru_shutdown(so));
510}
511
512/*
513 * key_sockaddr()
514 * derived from net/rtsock.c:rts_sockaddr()
515 */
516static int
517key_sockaddr(struct socket *so, struct sockaddr **nam)
518{
519	return(raw_usrreqs.pru_sockaddr(so, nam));
520}
521
522struct pr_usrreqs key_usrreqs = {
523	.pru_abort =		key_abort,
524	.pru_attach =		key_attach,
525	.pru_bind =		key_bind,
526	.pru_connect =		key_connect,
527	.pru_detach =		key_detach,
528	.pru_disconnect =	key_disconnect,
529	.pru_peeraddr =		key_peeraddr,
530	.pru_send =		key_send,
531	.pru_shutdown =		key_shutdown,
532	.pru_sockaddr =		key_sockaddr,
533	.pru_close =		key_close,
534};
535
536/* sysctl */
537SYSCTL_NODE(_net, PF_KEY, key, CTLFLAG_RW, 0, "Key Family");
538
539/*
540 * Definitions of protocols supported in the KEY domain.
541 */
542
543extern struct domain keydomain;
544
545struct protosw keysw[] = {
546{
547	.pr_type =		SOCK_RAW,
548	.pr_domain =		&keydomain,
549	.pr_protocol =		PF_KEY_V2,
550	.pr_flags =		PR_ATOMIC|PR_ADDR,
551	.pr_output =		key_output,
552	.pr_ctlinput =		raw_ctlinput,
553	.pr_init =		raw_init,
554	.pr_usrreqs =		&key_usrreqs
555}
556};
557
558static void
559key_init0(void)
560{
561	bzero((caddr_t)&V_key_cb, sizeof(V_key_cb));
562	key_init();
563}
564
565struct domain keydomain = {
566	.dom_family =		PF_KEY,
567	.dom_name =		"key",
568	.dom_init =		key_init0,
569	.dom_protosw =		keysw,
570	.dom_protoswNPROTOSW =	&keysw[sizeof(keysw)/sizeof(keysw[0])]
571};
572
573DOMAIN_SET(key);
574