xref: /netbsd-src/sys/netipsec/keysock.c (revision 4b896b232495b7a9b8b94a1cf1e21873296d53b8) 
1 /*	$NetBSD: keysock.c,v 1.4 2004/04/26 01:41:15 matt Exp $	*/
2 /*	$FreeBSD: src/sys/netipsec/keysock.c,v 1.3.2.1 2003/01/24 05:11:36 sam Exp $	*/
3 /*	$KAME: keysock.c,v 1.25 2001/08/13 20:07:41 itojun Exp $	*/
4 
5 /*
6  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the project nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 __KERNEL_RCSID(0, "$NetBSD: keysock.c,v 1.4 2004/04/26 01:41:15 matt Exp $");
36 
37 #include "opt_ipsec.h"
38 
39 /* This code has derived from sys/net/rtsock.c on FreeBSD2.2.5 */
40 
41 #include <sys/types.h>
42 #include <sys/param.h>
43 #include <sys/domain.h>
44 #include <sys/errno.h>
45 #include <sys/kernel.h>
46 #include <sys/malloc.h>
47 #include <sys/mbuf.h>
48 #include <sys/protosw.h>
49 #include <sys/signalvar.h>
50 #include <sys/socket.h>
51 #include <sys/socketvar.h>
52 #include <sys/sysctl.h>
53 #include <sys/systm.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 <netipsec/ipsec_osdep.h>
64 
65 #include <machine/stdarg.h>
66 
67 typedef int	pr_output_t (struct mbuf *, struct socket *);
68 
69 struct key_cb {
70 	int key_count;
71 	int any_count;
72 };
73 static struct key_cb key_cb;
74 
75 static struct sockaddr key_dst = { 2, PF_KEY, };
76 static struct sockaddr key_src = { 2, PF_KEY, };
77 
78 static int key_sendup0 __P((struct rawcb *, struct mbuf *, int));
79 
80 struct pfkeystat pfkeystat;
81 
82 /*
83  * key_output()
84  */
85 int
86 key_output(struct mbuf *m, ...)
87 {
88 	struct sadb_msg *msg;
89 	int len, error = 0;
90 	int s;
91 	struct socket *so;
92 	va_list ap;
93 
94 	va_start(ap, m);
95 	so = va_arg(ap, struct socket *);
96 	va_end(ap);
97 
98 	if (m == 0)
99 		panic("key_output: NULL pointer was passed.\n");
100 
101 	pfkeystat.out_total++;
102 	pfkeystat.out_bytes += m->m_pkthdr.len;
103 
104 	len = m->m_pkthdr.len;
105 	if (len < sizeof(struct sadb_msg)) {
106 		pfkeystat.out_tooshort++;
107 		error = EINVAL;
108 		goto end;
109 	}
110 
111 	if (m->m_len < sizeof(struct sadb_msg)) {
112 		if ((m = m_pullup(m, sizeof(struct sadb_msg))) == 0) {
113 			pfkeystat.out_nomem++;
114 			error = ENOBUFS;
115 			goto end;
116 		}
117 	}
118 
119 	if ((m->m_flags & M_PKTHDR) == 0)
120 		panic("key_output: not M_PKTHDR ??");
121 
122 	KEYDEBUG(KEYDEBUG_KEY_DUMP, kdebug_mbuf(m));
123 
124 	msg = mtod(m, struct sadb_msg *);
125 	pfkeystat.out_msgtype[msg->sadb_msg_type]++;
126 	if (len != PFKEY_UNUNIT64(msg->sadb_msg_len)) {
127 		pfkeystat.out_invlen++;
128 		error = EINVAL;
129 		goto end;
130 	}
131 
132 	/*XXX giant lock*/
133 	s = splsoftnet();
134 	error = key_parse(m, so);
135 	m = NULL;
136 	splx(s);
137 end:
138 	if (m)
139 		m_freem(m);
140 	return error;
141 }
142 
143 /*
144  * send message to the socket.
145  */
146 static int
147 key_sendup0(rp, m, promisc)
148 	struct rawcb *rp;
149 	struct mbuf *m;
150 	int promisc;
151 {
152 	int error;
153 
154 	if (promisc) {
155 		struct sadb_msg *pmsg;
156 
157 		M_PREPEND(m, sizeof(struct sadb_msg), M_DONTWAIT);
158 		if (m && m->m_len < sizeof(struct sadb_msg))
159 			m = m_pullup(m, sizeof(struct sadb_msg));
160 		if (!m) {
161 			pfkeystat.in_nomem++;
162 			m_freem(m);
163 			return ENOBUFS;
164 		}
165 		m->m_pkthdr.len += sizeof(*pmsg);
166 
167 		pmsg = mtod(m, struct sadb_msg *);
168 		bzero(pmsg, sizeof(*pmsg));
169 		pmsg->sadb_msg_version = PF_KEY_V2;
170 		pmsg->sadb_msg_type = SADB_X_PROMISC;
171 		pmsg->sadb_msg_len = PFKEY_UNIT64(m->m_pkthdr.len);
172 		/* pid and seq? */
173 
174 		pfkeystat.in_msgtype[pmsg->sadb_msg_type]++;
175 	}
176 
177 	if (!sbappendaddr(&rp->rcb_socket->so_rcv, (struct sockaddr *)&key_src,
178 	    m, NULL)) {
179 		pfkeystat.in_nomem++;
180 		m_freem(m);
181 		error = ENOBUFS;
182 	} else
183 		error = 0;
184 	sorwakeup(rp->rcb_socket);
185 	return error;
186 }
187 
188 /* XXX this interface should be obsoleted. */
189 int
190 key_sendup(so, msg, len, target)
191 	struct socket *so;
192 	struct sadb_msg *msg;
193 	u_int len;
194 	int target;	/*target of the resulting message*/
195 {
196 	struct mbuf *m, *n, *mprev;
197 	int tlen;
198 
199 	/* sanity check */
200 	if (so == 0 || msg == 0)
201 		panic("key_sendup: NULL pointer was passed.\n");
202 
203 	KEYDEBUG(KEYDEBUG_KEY_DUMP,
204 		printf("key_sendup: \n");
205 		kdebug_sadb(msg));
206 
207 	/*
208 	 * we increment statistics here, just in case we have ENOBUFS
209 	 * in this function.
210 	 */
211 	pfkeystat.in_total++;
212 	pfkeystat.in_bytes += len;
213 	pfkeystat.in_msgtype[msg->sadb_msg_type]++;
214 
215 	/*
216 	 * Get mbuf chain whenever possible (not clusters),
217 	 * to save socket buffer.  We'll be generating many SADB_ACQUIRE
218 	 * messages to listening key sockets.  If we simply allocate clusters,
219 	 * sbappendaddr() will raise ENOBUFS due to too little sbspace().
220 	 * sbspace() computes # of actual data bytes AND mbuf region.
221 	 *
222 	 * TODO: SADB_ACQUIRE filters should be implemented.
223 	 */
224 	tlen = len;
225 	m = mprev = NULL;
226 	while (tlen > 0) {
227 		if (tlen == len) {
228 			MGETHDR(n, M_DONTWAIT, MT_DATA);
229 			n->m_len = MHLEN;
230 		} else {
231 			MGET(n, M_DONTWAIT, MT_DATA);
232 			n->m_len = MLEN;
233 		}
234 		if (!n) {
235 			pfkeystat.in_nomem++;
236 			return ENOBUFS;
237 		}
238 		if (tlen >= MCLBYTES) {	/*XXX better threshold? */
239 			MCLGET(n, M_DONTWAIT);
240 			if ((n->m_flags & M_EXT) == 0) {
241 				m_free(n);
242 				m_freem(m);
243 				pfkeystat.in_nomem++;
244 				return ENOBUFS;
245 			}
246 			n->m_len = MCLBYTES;
247 		}
248 
249 		if (tlen < n->m_len)
250 			n->m_len = tlen;
251 		n->m_next = NULL;
252 		if (m == NULL)
253 			m = mprev = n;
254 		else {
255 			mprev->m_next = n;
256 			mprev = n;
257 		}
258 		tlen -= n->m_len;
259 		n = NULL;
260 	}
261 	m->m_pkthdr.len = len;
262 	m->m_pkthdr.rcvif = NULL;
263 	m_copyback(m, 0, len, (caddr_t)msg);
264 
265 	/* avoid duplicated statistics */
266 	pfkeystat.in_total--;
267 	pfkeystat.in_bytes -= len;
268 	pfkeystat.in_msgtype[msg->sadb_msg_type]--;
269 
270 	return key_sendup_mbuf(so, m, target);
271 }
272 
273 /* so can be NULL if target != KEY_SENDUP_ONE */
274 int
275 key_sendup_mbuf(so, m, target)
276 	struct socket *so;
277 	struct mbuf *m;
278 	int target;
279 {
280 	struct mbuf *n;
281 	struct keycb *kp;
282 	int sendup;
283 	struct rawcb *rp;
284 	int error = 0;
285 
286 	if (m == NULL)
287 		panic("key_sendup_mbuf: NULL pointer was passed.\n");
288 	if (so == NULL && target == KEY_SENDUP_ONE)
289 		panic("key_sendup_mbuf: NULL pointer was passed.\n");
290 
291 	pfkeystat.in_total++;
292 	pfkeystat.in_bytes += m->m_pkthdr.len;
293 	if (m->m_len < sizeof(struct sadb_msg)) {
294 #if 1
295 		m = m_pullup(m, sizeof(struct sadb_msg));
296 		if (m == NULL) {
297 			pfkeystat.in_nomem++;
298 			return ENOBUFS;
299 		}
300 #else
301 		/* don't bother pulling it up just for stats */
302 #endif
303 	}
304 	if (m->m_len >= sizeof(struct sadb_msg)) {
305 		struct sadb_msg *msg;
306 		msg = mtod(m, struct sadb_msg *);
307 		pfkeystat.in_msgtype[msg->sadb_msg_type]++;
308 	}
309 
310 	LIST_FOREACH(rp, &rawcb_list, rcb_list)
311 	{
312 		if (rp->rcb_proto.sp_family != PF_KEY)
313 			continue;
314 		if (rp->rcb_proto.sp_protocol
315 		 && rp->rcb_proto.sp_protocol != PF_KEY_V2) {
316 			continue;
317 		}
318 
319 		kp = (struct keycb *)rp;
320 
321 		/*
322 		 * If you are in promiscuous mode, and when you get broadcasted
323 		 * reply, you'll get two PF_KEY messages.
324 		 * (based on pf_key@inner.net message on 14 Oct 1998)
325 		 */
326 		if (((struct keycb *)rp)->kp_promisc) {
327 			if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
328 				(void)key_sendup0(rp, n, 1);
329 				n = NULL;
330 			}
331 		}
332 
333 		/* the exact target will be processed later */
334 		if (so && sotorawcb(so) == rp)
335 			continue;
336 
337 		sendup = 0;
338 		switch (target) {
339 		case KEY_SENDUP_ONE:
340 			/* the statement has no effect */
341 			if (so && sotorawcb(so) == rp)
342 				sendup++;
343 			break;
344 		case KEY_SENDUP_ALL:
345 			sendup++;
346 			break;
347 		case KEY_SENDUP_REGISTERED:
348 			if (kp->kp_registered)
349 				sendup++;
350 			break;
351 		}
352 		pfkeystat.in_msgtarget[target]++;
353 
354 		if (!sendup)
355 			continue;
356 
357 		if ((n = m_copy(m, 0, (int)M_COPYALL)) == NULL) {
358 			m_freem(m);
359 			pfkeystat.in_nomem++;
360 			return ENOBUFS;
361 		}
362 
363 		if ((error = key_sendup0(rp, n, 0)) != 0) {
364 			m_freem(m);
365 			return error;
366 		}
367 
368 		n = NULL;
369 	}
370 
371 	if (so) {
372 		error = key_sendup0(sotorawcb(so), m, 0);
373 		m = NULL;
374 	} else {
375 		error = 0;
376 		m_freem(m);
377 	}
378 	return error;
379 }
380 
381 #ifdef __FreeBSD__
382 
383 /*
384  * key_abort()
385  * derived from net/rtsock.c:rts_abort()
386  */
387 static int
388 key_abort(struct socket *so)
389 {
390 	int s, error;
391 	s = splnet(); 	/* FreeBSD */
392 	error = raw_usrreqs.pru_abort(so);
393 	splx(s);
394 	return error;
395 }
396 
397 /*
398  * key_attach()
399  * derived from net/rtsock.c:rts_attach()
400  */
401 static int
402 key_attach(struct socket *so, int proto, struct proc *td)
403 {
404 	struct keycb *kp;
405 	int s, error;
406 
407 	if (sotorawcb(so) != 0)
408 		return EISCONN;	/* XXX panic? */
409 	kp = (struct keycb *)malloc(sizeof *kp, M_PCB, M_WAITOK|M_ZERO); /* XXX */
410 	if (kp == 0)
411 		return ENOBUFS;
412 
413 	/*
414 	 * The spl[soft]net() is necessary to block protocols from sending
415 	 * error notifications (like RTM_REDIRECT or RTM_LOSING) while
416 	 * this PCB is extant but incompletely initialized.
417 	 * Probably we should try to do more of this work beforehand and
418 	 * eliminate the spl.
419 	 */
420 	s = splnet();	/* FreeBSD */
421 	so->so_pcb = (caddr_t)kp;
422 	error = raw_usrreqs.pru_attach(so, proto, td);
423 	kp = (struct keycb *)sotorawcb(so);
424 	if (error) {
425 		free(kp, M_PCB);
426 		so->so_pcb = (caddr_t) 0;
427 		splx(s);
428 		return error;
429 	}
430 
431 	kp->kp_promisc = kp->kp_registered = 0;
432 
433 	if (kp->kp_raw.rcb_proto.sp_protocol == PF_KEY) /* XXX: AF_KEY */
434 		key_cb.key_count++;
435 	key_cb.any_count++;
436 	kp->kp_raw.rcb_laddr = &key_src;
437 	kp->kp_raw.rcb_faddr = &key_dst;
438 	soisconnected(so);
439 	so->so_options |= SO_USELOOPBACK;
440 
441 	splx(s);
442 	return 0;
443 }
444 
445 /*
446  * key_bind()
447  * derived from net/rtsock.c:rts_bind()
448  */
449 static int
450 key_bind(struct socket *so, struct sockaddr *nam, struct proc *td)
451 {
452 	int s, error;
453 	s = splnet();	/* FreeBSD */
454 	error = raw_usrreqs.pru_bind(so, nam, td); /* xxx just EINVAL */
455 	splx(s);
456 	return error;
457 }
458 
459 /*
460  * key_connect()
461  * derived from net/rtsock.c:rts_connect()
462  */
463 static int
464 key_connect(struct socket *so, struct sockaddr *nam, struct proc *td)
465 {
466 	int s, error;
467 	s = splnet();	/* FreeBSD */
468 	error = raw_usrreqs.pru_connect(so, nam, td); /* XXX just EINVAL */
469 	splx(s);
470 	return error;
471 }
472 
473 /*
474  * key_detach()
475  * derived from net/rtsock.c:rts_detach()
476  */
477 static int
478 key_detach(struct socket *so)
479 {
480 	struct keycb *kp = (struct keycb *)sotorawcb(so);
481 	int s, error;
482 
483 	s = splnet();	/* FreeBSD */
484 	if (kp != 0) {
485 		if (kp->kp_raw.rcb_proto.sp_protocol
486 		    == PF_KEY) /* XXX: AF_KEY */
487 			key_cb.key_count--;
488 		key_cb.any_count--;
489 
490 		key_freereg(so);
491 	}
492 	error = raw_usrreqs.pru_detach(so);
493 	splx(s);
494 	return error;
495 }
496 
497 /*
498  * key_disconnect()
499  * derived from net/rtsock.c:key_disconnect()
500  */
501 static int
502 key_disconnect(struct socket *so)
503 {
504 	int s, error;
505 	s = splnet();	/* FreeBSD */
506 	error = raw_usrreqs.pru_disconnect(so);
507 	splx(s);
508 	return error;
509 }
510 
511 /*
512  * key_peeraddr()
513  * derived from net/rtsock.c:rts_peeraddr()
514  */
515 static int
516 key_peeraddr(struct socket *so, struct sockaddr **nam)
517 {
518 	int s, error;
519 	s = splnet();	/* FreeBSD */
520 	error = raw_usrreqs.pru_peeraddr(so, nam);
521 	splx(s);
522 	return error;
523 }
524 
525 /*
526  * key_send()
527  * derived from net/rtsock.c:rts_send()
528  */
529 static int
530 key_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
531 	 struct mbuf *control, struct proc *td)
532 {
533 	int s, error;
534 	s = splnet();	/* FreeBSD */
535 	error = raw_usrreqs.pru_send(so, flags, m, nam, control, td);
536 	splx(s);
537 	return error;
538 }
539 
540 /*
541  * key_shutdown()
542  * derived from net/rtsock.c:rts_shutdown()
543  */
544 static int
545 key_shutdown(struct socket *so)
546 {
547 	int s, error;
548 	s = splnet();	/* FreeBSD */
549 	error = raw_usrreqs.pru_shutdown(so);
550 	splx(s);
551 	return error;
552 }
553 
554 /*
555  * key_sockaddr()
556  * derived from net/rtsock.c:rts_sockaddr()
557  */
558 static int
559 key_sockaddr(struct socket *so, struct sockaddr **nam)
560 {
561 	int s, error;
562 	s = splnet();	/* FreeBSD */
563 	error = raw_usrreqs.pru_sockaddr(so, nam);
564 	splx(s);
565 	return error;
566 }
567 #else /*!__FreeBSD__ -- traditional proto_usrreq() switch */
568 
569 /*
570  * key_usrreq()
571  * derived from net/rtsock.c:route_usrreq()
572  */
573 int
574 key_usrreq(so, req, m, nam, control, p)
575 	struct socket *so;
576 	int req;
577 	struct mbuf *m, *nam, *control;
578 	struct proc *p;
579 {
580 	int error = 0;
581 	struct keycb *kp = (struct keycb *)sotorawcb(so);
582 	int s;
583 
584 	s = splsoftnet();
585 	if (req == PRU_ATTACH) {
586 		kp = (struct keycb *)malloc(sizeof(*kp), M_PCB, M_WAITOK);
587 		so->so_pcb = (caddr_t)kp;
588 		if (so->so_pcb)
589 			bzero(so->so_pcb, sizeof(*kp));
590 	}
591 	if (req == PRU_DETACH && kp) {
592 		int af = kp->kp_raw.rcb_proto.sp_protocol;
593 		if (af == PF_KEY) /* XXX: AF_KEY */
594 			key_cb.key_count--;
595 		key_cb.any_count--;
596 
597 		key_freereg(so);
598 	}
599 
600 	error = raw_usrreq(so, req, m, nam, control, p);
601 	m = control = NULL;	/* reclaimed in raw_usrreq */
602 	kp = (struct keycb *)sotorawcb(so);
603 	if (req == PRU_ATTACH && kp) {
604 		int af = kp->kp_raw.rcb_proto.sp_protocol;
605 		if (error) {
606 			pfkeystat.sockerr++;
607 			free((caddr_t)kp, M_PCB);
608 			so->so_pcb = (caddr_t) 0;
609 			splx(s);
610 			return (error);
611 		}
612 
613 		kp->kp_promisc = kp->kp_registered = 0;
614 
615 		if (af == PF_KEY) /* XXX: AF_KEY */
616 			key_cb.key_count++;
617 		key_cb.any_count++;
618 		kp->kp_raw.rcb_laddr = &key_src;
619 		kp->kp_raw.rcb_faddr = &key_dst;
620 		soisconnected(so);
621 		so->so_options |= SO_USELOOPBACK;
622 	}
623 	splx(s);
624 	return (error);
625 }
626 #endif /*!__FreeBSD__*/
627 
628 /* sysctl */
629 #ifdef SYSCTL_NODE
630 SYSCTL_NODE(_net, PF_KEY, key, CTLFLAG_RW, 0, "Key Family");
631 #endif /* SYSCTL_NODE */
632 
633 /*
634  * Definitions of protocols supported in the KEY domain.
635  */
636 
637 /* This extern declaration is all that's common... */
638 extern struct domain keydomain;
639 
640 #ifdef __FreeBSD__
641 struct pr_usrreqs key_usrreqs = {
642 	key_abort, pru_accept_notsupp, key_attach, key_bind,
643 	key_connect,
644 	pru_connect2_notsupp, pru_control_notsupp, key_detach,
645 	key_disconnect, pru_listen_notsupp, key_peeraddr,
646 	pru_rcvd_notsupp,
647 	pru_rcvoob_notsupp, key_send, pru_sense_null, key_shutdown,
648 	key_sockaddr, sosend, soreceive, sopoll
649 };
650 
651 struct protosw keysw[] = {
652 { SOCK_RAW,	&keydomain,	PF_KEY_V2,	PR_ATOMIC|PR_ADDR,
653   0,		(pr_output_t *)key_output,	raw_ctlinput, 0,
654   0,
655   raw_init,	0,		0,		0,
656   &key_usrreqs
657 }
658 };
659 
660 static void
661 key_init0(void)
662 {
663 	bzero((caddr_t)&key_cb, sizeof(key_cb));
664 	key_init();
665 }
666 
667 struct domain keydomain =
668     { PF_KEY, "key", key_init0, 0, 0,
669       keysw, &keysw[sizeof(keysw)/sizeof(keysw[0])] };
670 
671 DOMAIN_SET(key);
672 
673 #else /* !__FreeBSD__ */
674 
675 
676 struct protosw keysw[] = {
677 { SOCK_RAW,	&keydomain,	PF_KEY_V2,	PR_ATOMIC|PR_ADDR,
678   0,		key_output,	raw_ctlinput,	0,
679   key_usrreq,
680   raw_init,	0,		0,		0,
681   NULL,
682 }
683 };
684 
685 struct domain keydomain =
686     { PF_KEY, "key", key_init, 0, 0,
687       keysw, &keysw[sizeof(keysw)/sizeof(keysw[0])] };
688 
689 #endif
690