xref: /freebsd/sys/netipsec/keysock.c (revision f9218d3d4fd34f082473b3a021c6d4d109fb47cf)
1 /*	$FreeBSD$	*/
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/malloc.h>
43 #include <sys/mbuf.h>
44 #include <sys/protosw.h>
45 #include <sys/signalvar.h>
46 #include <sys/socket.h>
47 #include <sys/socketvar.h>
48 #include <sys/sysctl.h>
49 #include <sys/systm.h>
50 
51 #include <net/raw_cb.h>
52 #include <net/route.h>
53 
54 #include <net/pfkeyv2.h>
55 #include <netipsec/key.h>
56 #include <netipsec/keysock.h>
57 #include <netipsec/key_debug.h>
58 
59 #include <machine/stdarg.h>
60 
61 struct key_cb {
62 	int key_count;
63 	int any_count;
64 };
65 static struct key_cb key_cb;
66 
67 static struct sockaddr key_dst = { 2, PF_KEY, };
68 static struct sockaddr key_src = { 2, PF_KEY, };
69 
70 static int key_sendup0 __P((struct rawcb *, struct mbuf *, int));
71 
72 struct pfkeystat pfkeystat;
73 
74 /*
75  * key_output()
76  */
77 int
78 #if __STDC__
79 key_output(struct mbuf *m, ...)
80 #else
81 key_output(m, va_alist)
82 	struct mbuf *m;
83 	va_dcl
84 #endif
85 {
86 	struct sadb_msg *msg;
87 	int len, error = 0;
88 	int s;
89 	struct socket *so;
90 	va_list ap;
91 
92 	va_start(ap, m);
93 	so = va_arg(ap, struct socket *);
94 	va_end(ap);
95 
96 	if (m == 0)
97 		panic("key_output: NULL pointer was passed.\n");
98 
99 	pfkeystat.out_total++;
100 	pfkeystat.out_bytes += m->m_pkthdr.len;
101 
102 	len = m->m_pkthdr.len;
103 	if (len < sizeof(struct sadb_msg)) {
104 		pfkeystat.out_tooshort++;
105 		error = EINVAL;
106 		goto end;
107 	}
108 
109 	if (m->m_len < sizeof(struct sadb_msg)) {
110 		if ((m = m_pullup(m, sizeof(struct sadb_msg))) == 0) {
111 			pfkeystat.out_nomem++;
112 			error = ENOBUFS;
113 			goto end;
114 		}
115 	}
116 
117 	if ((m->m_flags & M_PKTHDR) == 0)
118 		panic("key_output: not M_PKTHDR ??");
119 
120 	KEYDEBUG(KEYDEBUG_KEY_DUMP, kdebug_mbuf(m));
121 
122 	msg = mtod(m, struct sadb_msg *);
123 	pfkeystat.out_msgtype[msg->sadb_msg_type]++;
124 	if (len != PFKEY_UNUNIT64(msg->sadb_msg_len)) {
125 		pfkeystat.out_invlen++;
126 		error = EINVAL;
127 		goto end;
128 	}
129 
130 	/*XXX giant lock*/
131 	s = splnet();
132 	error = key_parse(m, so);
133 	m = NULL;
134 	splx(s);
135 end:
136 	if (m)
137 		m_freem(m);
138 	return error;
139 }
140 
141 /*
142  * send message to the socket.
143  */
144 static int
145 key_sendup0(rp, m, promisc)
146 	struct rawcb *rp;
147 	struct mbuf *m;
148 	int promisc;
149 {
150 	int error;
151 
152 	if (promisc) {
153 		struct sadb_msg *pmsg;
154 
155 		M_PREPEND(m, sizeof(struct sadb_msg), M_DONTWAIT);
156 		if (m && m->m_len < sizeof(struct sadb_msg))
157 			m = m_pullup(m, sizeof(struct sadb_msg));
158 		if (!m) {
159 			pfkeystat.in_nomem++;
160 			m_freem(m);
161 			return ENOBUFS;
162 		}
163 		m->m_pkthdr.len += sizeof(*pmsg);
164 
165 		pmsg = mtod(m, struct sadb_msg *);
166 		bzero(pmsg, sizeof(*pmsg));
167 		pmsg->sadb_msg_version = PF_KEY_V2;
168 		pmsg->sadb_msg_type = SADB_X_PROMISC;
169 		pmsg->sadb_msg_len = PFKEY_UNIT64(m->m_pkthdr.len);
170 		/* pid and seq? */
171 
172 		pfkeystat.in_msgtype[pmsg->sadb_msg_type]++;
173 	}
174 
175 	if (!sbappendaddr(&rp->rcb_socket->so_rcv, (struct sockaddr *)&key_src,
176 	    m, NULL)) {
177 		pfkeystat.in_nomem++;
178 		m_freem(m);
179 		error = ENOBUFS;
180 	} else
181 		error = 0;
182 	sorwakeup(rp->rcb_socket);
183 	return error;
184 }
185 
186 /* XXX this interface should be obsoleted. */
187 int
188 key_sendup(so, msg, len, target)
189 	struct socket *so;
190 	struct sadb_msg *msg;
191 	u_int len;
192 	int target;	/*target of the resulting message*/
193 {
194 	struct mbuf *m, *n, *mprev;
195 	int tlen;
196 
197 	/* sanity check */
198 	if (so == 0 || msg == 0)
199 		panic("key_sendup: NULL pointer was passed.\n");
200 
201 	KEYDEBUG(KEYDEBUG_KEY_DUMP,
202 		printf("key_sendup: \n");
203 		kdebug_sadb(msg));
204 
205 	/*
206 	 * we increment statistics here, just in case we have ENOBUFS
207 	 * in this function.
208 	 */
209 	pfkeystat.in_total++;
210 	pfkeystat.in_bytes += len;
211 	pfkeystat.in_msgtype[msg->sadb_msg_type]++;
212 
213 	/*
214 	 * Get mbuf chain whenever possible (not clusters),
215 	 * to save socket buffer.  We'll be generating many SADB_ACQUIRE
216 	 * messages to listening key sockets.  If we simply allocate clusters,
217 	 * sbappendaddr() will raise ENOBUFS due to too little sbspace().
218 	 * sbspace() computes # of actual data bytes AND mbuf region.
219 	 *
220 	 * TODO: SADB_ACQUIRE filters should be implemented.
221 	 */
222 	tlen = len;
223 	m = mprev = NULL;
224 	while (tlen > 0) {
225 		if (tlen == len) {
226 			MGETHDR(n, M_DONTWAIT, MT_DATA);
227 			n->m_len = MHLEN;
228 		} else {
229 			MGET(n, M_DONTWAIT, MT_DATA);
230 			n->m_len = MLEN;
231 		}
232 		if (!n) {
233 			pfkeystat.in_nomem++;
234 			return ENOBUFS;
235 		}
236 		if (tlen >= MCLBYTES) {	/*XXX better threshold? */
237 			MCLGET(n, M_DONTWAIT);
238 			if ((n->m_flags & M_EXT) == 0) {
239 				m_free(n);
240 				m_freem(m);
241 				pfkeystat.in_nomem++;
242 				return ENOBUFS;
243 			}
244 			n->m_len = MCLBYTES;
245 		}
246 
247 		if (tlen < n->m_len)
248 			n->m_len = tlen;
249 		n->m_next = NULL;
250 		if (m == NULL)
251 			m = mprev = n;
252 		else {
253 			mprev->m_next = n;
254 			mprev = n;
255 		}
256 		tlen -= n->m_len;
257 		n = NULL;
258 	}
259 	m->m_pkthdr.len = len;
260 	m->m_pkthdr.rcvif = NULL;
261 	m_copyback(m, 0, len, (caddr_t)msg);
262 
263 	/* avoid duplicated statistics */
264 	pfkeystat.in_total--;
265 	pfkeystat.in_bytes -= len;
266 	pfkeystat.in_msgtype[msg->sadb_msg_type]--;
267 
268 	return key_sendup_mbuf(so, m, target);
269 }
270 
271 /* so can be NULL if target != KEY_SENDUP_ONE */
272 int
273 key_sendup_mbuf(so, m, target)
274 	struct socket *so;
275 	struct mbuf *m;
276 	int target;
277 {
278 	struct mbuf *n;
279 	struct keycb *kp;
280 	int sendup;
281 	struct rawcb *rp;
282 	int error = 0;
283 
284 	if (m == NULL)
285 		panic("key_sendup_mbuf: NULL pointer was passed.\n");
286 	if (so == NULL && target == KEY_SENDUP_ONE)
287 		panic("key_sendup_mbuf: NULL pointer was passed.\n");
288 
289 	pfkeystat.in_total++;
290 	pfkeystat.in_bytes += m->m_pkthdr.len;
291 	if (m->m_len < sizeof(struct sadb_msg)) {
292 #if 1
293 		m = m_pullup(m, sizeof(struct sadb_msg));
294 		if (m == NULL) {
295 			pfkeystat.in_nomem++;
296 			return ENOBUFS;
297 		}
298 #else
299 		/* don't bother pulling it up just for stats */
300 #endif
301 	}
302 	if (m->m_len >= sizeof(struct sadb_msg)) {
303 		struct sadb_msg *msg;
304 		msg = mtod(m, struct sadb_msg *);
305 		pfkeystat.in_msgtype[msg->sadb_msg_type]++;
306 	}
307 
308 	LIST_FOREACH(rp, &rawcb_list, list)
309 	{
310 		if (rp->rcb_proto.sp_family != PF_KEY)
311 			continue;
312 		if (rp->rcb_proto.sp_protocol
313 		 && rp->rcb_proto.sp_protocol != PF_KEY_V2) {
314 			continue;
315 		}
316 
317 		kp = (struct keycb *)rp;
318 
319 		/*
320 		 * If you are in promiscuous mode, and when you get broadcasted
321 		 * reply, you'll get two PF_KEY messages.
322 		 * (based on pf_key@inner.net message on 14 Oct 1998)
323 		 */
324 		if (((struct keycb *)rp)->kp_promisc) {
325 			if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
326 				(void)key_sendup0(rp, n, 1);
327 				n = NULL;
328 			}
329 		}
330 
331 		/* the exact target will be processed later */
332 		if (so && sotorawcb(so) == rp)
333 			continue;
334 
335 		sendup = 0;
336 		switch (target) {
337 		case KEY_SENDUP_ONE:
338 			/* the statement has no effect */
339 			if (so && sotorawcb(so) == rp)
340 				sendup++;
341 			break;
342 		case KEY_SENDUP_ALL:
343 			sendup++;
344 			break;
345 		case KEY_SENDUP_REGISTERED:
346 			if (kp->kp_registered)
347 				sendup++;
348 			break;
349 		}
350 		pfkeystat.in_msgtarget[target]++;
351 
352 		if (!sendup)
353 			continue;
354 
355 		if ((n = m_copy(m, 0, (int)M_COPYALL)) == NULL) {
356 			m_freem(m);
357 			pfkeystat.in_nomem++;
358 			return ENOBUFS;
359 		}
360 
361 		if ((error = key_sendup0(rp, n, 0)) != 0) {
362 			m_freem(m);
363 			return error;
364 		}
365 
366 		n = NULL;
367 	}
368 
369 	if (so) {
370 		error = key_sendup0(sotorawcb(so), m, 0);
371 		m = NULL;
372 	} else {
373 		error = 0;
374 		m_freem(m);
375 	}
376 	return error;
377 }
378 
379 /*
380  * key_abort()
381  * derived from net/rtsock.c:rts_abort()
382  */
383 static int
384 key_abort(struct socket *so)
385 {
386 	int s, error;
387 	s = splnet();
388 	error = raw_usrreqs.pru_abort(so);
389 	splx(s);
390 	return error;
391 }
392 
393 /*
394  * key_attach()
395  * derived from net/rtsock.c:rts_attach()
396  */
397 static int
398 key_attach(struct socket *so, int proto, struct thread *td)
399 {
400 	struct keycb *kp;
401 	int s, error;
402 
403 	if (sotorawcb(so) != 0)
404 		return EISCONN;	/* XXX panic? */
405 	kp = (struct keycb *)malloc(sizeof *kp, M_PCB, M_WAITOK|M_ZERO); /* XXX */
406 	if (kp == 0)
407 		return ENOBUFS;
408 
409 	/*
410 	 * The splnet() is necessary to block protocols from sending
411 	 * error notifications (like RTM_REDIRECT or RTM_LOSING) while
412 	 * this PCB is extant but incompletely initialized.
413 	 * Probably we should try to do more of this work beforehand and
414 	 * eliminate the spl.
415 	 */
416 	s = splnet();
417 	so->so_pcb = (caddr_t)kp;
418 	error = raw_usrreqs.pru_attach(so, proto, td);
419 	kp = (struct keycb *)sotorawcb(so);
420 	if (error) {
421 		free(kp, M_PCB);
422 		so->so_pcb = (caddr_t) 0;
423 		splx(s);
424 		return error;
425 	}
426 
427 	kp->kp_promisc = kp->kp_registered = 0;
428 
429 	if (kp->kp_raw.rcb_proto.sp_protocol == PF_KEY) /* XXX: AF_KEY */
430 		key_cb.key_count++;
431 	key_cb.any_count++;
432 	kp->kp_raw.rcb_laddr = &key_src;
433 	kp->kp_raw.rcb_faddr = &key_dst;
434 	soisconnected(so);
435 	so->so_options |= SO_USELOOPBACK;
436 
437 	splx(s);
438 	return 0;
439 }
440 
441 /*
442  * key_bind()
443  * derived from net/rtsock.c:rts_bind()
444  */
445 static int
446 key_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
447 {
448 	int s, error;
449 	s = splnet();
450 	error = raw_usrreqs.pru_bind(so, nam, td); /* xxx just EINVAL */
451 	splx(s);
452 	return error;
453 }
454 
455 /*
456  * key_connect()
457  * derived from net/rtsock.c:rts_connect()
458  */
459 static int
460 key_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
461 {
462 	int s, error;
463 	s = splnet();
464 	error = raw_usrreqs.pru_connect(so, nam, td); /* XXX just EINVAL */
465 	splx(s);
466 	return error;
467 }
468 
469 /*
470  * key_detach()
471  * derived from net/rtsock.c:rts_detach()
472  */
473 static int
474 key_detach(struct socket *so)
475 {
476 	struct keycb *kp = (struct keycb *)sotorawcb(so);
477 	int s, error;
478 
479 	s = splnet();
480 	if (kp != 0) {
481 		if (kp->kp_raw.rcb_proto.sp_protocol
482 		    == PF_KEY) /* XXX: AF_KEY */
483 			key_cb.key_count--;
484 		key_cb.any_count--;
485 
486 		key_freereg(so);
487 	}
488 	error = raw_usrreqs.pru_detach(so);
489 	splx(s);
490 	return error;
491 }
492 
493 /*
494  * key_disconnect()
495  * derived from net/rtsock.c:key_disconnect()
496  */
497 static int
498 key_disconnect(struct socket *so)
499 {
500 	int s, error;
501 	s = splnet();
502 	error = raw_usrreqs.pru_disconnect(so);
503 	splx(s);
504 	return error;
505 }
506 
507 /*
508  * key_peeraddr()
509  * derived from net/rtsock.c:rts_peeraddr()
510  */
511 static int
512 key_peeraddr(struct socket *so, struct sockaddr **nam)
513 {
514 	int s, error;
515 	s = splnet();
516 	error = raw_usrreqs.pru_peeraddr(so, nam);
517 	splx(s);
518 	return error;
519 }
520 
521 /*
522  * key_send()
523  * derived from net/rtsock.c:rts_send()
524  */
525 static int
526 key_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
527 	 struct mbuf *control, struct thread *td)
528 {
529 	int s, error;
530 	s = splnet();
531 	error = raw_usrreqs.pru_send(so, flags, m, nam, control, td);
532 	splx(s);
533 	return error;
534 }
535 
536 /*
537  * key_shutdown()
538  * derived from net/rtsock.c:rts_shutdown()
539  */
540 static int
541 key_shutdown(struct socket *so)
542 {
543 	int s, error;
544 	s = splnet();
545 	error = raw_usrreqs.pru_shutdown(so);
546 	splx(s);
547 	return error;
548 }
549 
550 /*
551  * key_sockaddr()
552  * derived from net/rtsock.c:rts_sockaddr()
553  */
554 static int
555 key_sockaddr(struct socket *so, struct sockaddr **nam)
556 {
557 	int s, error;
558 	s = splnet();
559 	error = raw_usrreqs.pru_sockaddr(so, nam);
560 	splx(s);
561 	return error;
562 }
563 
564 struct pr_usrreqs key_usrreqs = {
565 	key_abort, pru_accept_notsupp, key_attach, key_bind,
566 	key_connect,
567 	pru_connect2_notsupp, pru_control_notsupp, key_detach,
568 	key_disconnect, pru_listen_notsupp, key_peeraddr,
569 	pru_rcvd_notsupp,
570 	pru_rcvoob_notsupp, key_send, pru_sense_null, key_shutdown,
571 	key_sockaddr, sosend, soreceive, sopoll
572 };
573 
574 /* sysctl */
575 SYSCTL_NODE(_net, PF_KEY, key, CTLFLAG_RW, 0, "Key Family");
576 
577 /*
578  * Definitions of protocols supported in the KEY domain.
579  */
580 
581 extern struct domain keydomain;
582 
583 struct protosw keysw[] = {
584 { SOCK_RAW,	&keydomain,	PF_KEY_V2,	PR_ATOMIC|PR_ADDR,
585   0,		(pr_output_t *)key_output,	raw_ctlinput, 0,
586   0,
587   raw_init,	0,		0,		0,
588   &key_usrreqs
589 }
590 };
591 
592 static void
593 key_init0(void)
594 {
595 	bzero((caddr_t)&key_cb, sizeof(key_cb));
596 	key_init();
597 }
598 
599 struct domain keydomain =
600     { PF_KEY, "key", key_init0, 0, 0,
601       keysw, &keysw[sizeof(keysw)/sizeof(keysw[0])] };
602 
603 DOMAIN_SET(key);
604