xref: /freebsd/sys/netipsec/keysock.c (revision 6c6c03be2ddb04c54e455122799923deaefa4114)
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/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/if.h>
56 #include <net/raw_cb.h>
57 #include <net/route.h>
58 
59 #include <netinet/in.h>
60 
61 #include <net/pfkeyv2.h>
62 #include <netipsec/key.h>
63 #include <netipsec/keysock.h>
64 #include <netipsec/key_debug.h>
65 #include <netipsec/ipsec.h>
66 
67 #include <machine/stdarg.h>
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_src = { 2, PF_KEY, };
76 
77 static int key_sendup0 __P((struct rawcb *, struct mbuf *, int));
78 
79 struct pfkeystat pfkeystat;
80 
81 /*
82  * key_output()
83  */
84 int
85 key_output(struct mbuf *m, struct socket *so)
86 {
87 	INIT_VNET_IPSEC(curvnet);
88 	struct sadb_msg *msg;
89 	int len, error = 0;
90 
91 	if (m == 0)
92 		panic("%s: NULL pointer was passed.\n", __func__);
93 
94 	V_pfkeystat.out_total++;
95 	V_pfkeystat.out_bytes += m->m_pkthdr.len;
96 
97 	len = m->m_pkthdr.len;
98 	if (len < sizeof(struct sadb_msg)) {
99 		V_pfkeystat.out_tooshort++;
100 		error = EINVAL;
101 		goto end;
102 	}
103 
104 	if (m->m_len < sizeof(struct sadb_msg)) {
105 		if ((m = m_pullup(m, sizeof(struct sadb_msg))) == 0) {
106 			V_pfkeystat.out_nomem++;
107 			error = ENOBUFS;
108 			goto end;
109 		}
110 	}
111 
112 	M_ASSERTPKTHDR(m);
113 
114 	KEYDEBUG(KEYDEBUG_KEY_DUMP, kdebug_mbuf(m));
115 
116 	msg = mtod(m, struct sadb_msg *);
117 	V_pfkeystat.out_msgtype[msg->sadb_msg_type]++;
118 	if (len != PFKEY_UNUNIT64(msg->sadb_msg_len)) {
119 		V_pfkeystat.out_invlen++;
120 		error = EINVAL;
121 		goto end;
122 	}
123 
124 	error = key_parse(m, so);
125 	m = NULL;
126 end:
127 	if (m)
128 		m_freem(m);
129 	return error;
130 }
131 
132 /*
133  * send message to the socket.
134  */
135 static int
136 key_sendup0(rp, m, promisc)
137 	struct rawcb *rp;
138 	struct mbuf *m;
139 	int promisc;
140 {
141 	INIT_VNET_IPSEC(curvnet);
142 	int error;
143 
144 	if (promisc) {
145 		struct sadb_msg *pmsg;
146 
147 		M_PREPEND(m, sizeof(struct sadb_msg), M_DONTWAIT);
148 		if (m && m->m_len < sizeof(struct sadb_msg))
149 			m = m_pullup(m, sizeof(struct sadb_msg));
150 		if (!m) {
151 			V_pfkeystat.in_nomem++;
152 			m_freem(m);
153 			return ENOBUFS;
154 		}
155 		m->m_pkthdr.len += sizeof(*pmsg);
156 
157 		pmsg = mtod(m, struct sadb_msg *);
158 		bzero(pmsg, sizeof(*pmsg));
159 		pmsg->sadb_msg_version = PF_KEY_V2;
160 		pmsg->sadb_msg_type = SADB_X_PROMISC;
161 		pmsg->sadb_msg_len = PFKEY_UNIT64(m->m_pkthdr.len);
162 		/* pid and seq? */
163 
164 		V_pfkeystat.in_msgtype[pmsg->sadb_msg_type]++;
165 	}
166 
167 	if (!sbappendaddr(&rp->rcb_socket->so_rcv, (struct sockaddr *)&V_key_src,
168 	    m, NULL)) {
169 		V_pfkeystat.in_nomem++;
170 		m_freem(m);
171 		error = ENOBUFS;
172 	} else
173 		error = 0;
174 	sorwakeup(rp->rcb_socket);
175 	return error;
176 }
177 
178 /* XXX this interface should be obsoleted. */
179 int
180 key_sendup(so, msg, len, target)
181 	struct socket *so;
182 	struct sadb_msg *msg;
183 	u_int len;
184 	int target;	/*target of the resulting message*/
185 {
186 	INIT_VNET_IPSEC(curvnet);
187 	struct mbuf *m, *n, *mprev;
188 	int tlen;
189 
190 	/* sanity check */
191 	if (so == 0 || msg == 0)
192 		panic("%s: NULL pointer was passed.\n", __func__);
193 
194 	KEYDEBUG(KEYDEBUG_KEY_DUMP,
195 		printf("%s: \n", __func__);
196 		kdebug_sadb(msg));
197 
198 	/*
199 	 * we increment statistics here, just in case we have ENOBUFS
200 	 * in this function.
201 	 */
202 	V_pfkeystat.in_total++;
203 	V_pfkeystat.in_bytes += len;
204 	V_pfkeystat.in_msgtype[msg->sadb_msg_type]++;
205 
206 	/*
207 	 * Get mbuf chain whenever possible (not clusters),
208 	 * to save socket buffer.  We'll be generating many SADB_ACQUIRE
209 	 * messages to listening key sockets.  If we simply allocate clusters,
210 	 * sbappendaddr() will raise ENOBUFS due to too little sbspace().
211 	 * sbspace() computes # of actual data bytes AND mbuf region.
212 	 *
213 	 * TODO: SADB_ACQUIRE filters should be implemented.
214 	 */
215 	tlen = len;
216 	m = mprev = NULL;
217 	while (tlen > 0) {
218 		if (tlen == len) {
219 			MGETHDR(n, M_DONTWAIT, MT_DATA);
220 			if (n == NULL) {
221 				V_pfkeystat.in_nomem++;
222 				return ENOBUFS;
223 			}
224 			n->m_len = MHLEN;
225 		} else {
226 			MGET(n, M_DONTWAIT, MT_DATA);
227 			if (n == NULL) {
228 				V_pfkeystat.in_nomem++;
229 				return ENOBUFS;
230 			}
231 			n->m_len = MLEN;
232 		}
233 		if (tlen >= MCLBYTES) {	/*XXX better threshold? */
234 			MCLGET(n, M_DONTWAIT);
235 			if ((n->m_flags & M_EXT) == 0) {
236 				m_free(n);
237 				m_freem(m);
238 				V_pfkeystat.in_nomem++;
239 				return ENOBUFS;
240 			}
241 			n->m_len = MCLBYTES;
242 		}
243 
244 		if (tlen < n->m_len)
245 			n->m_len = tlen;
246 		n->m_next = NULL;
247 		if (m == NULL)
248 			m = mprev = n;
249 		else {
250 			mprev->m_next = n;
251 			mprev = n;
252 		}
253 		tlen -= n->m_len;
254 		n = NULL;
255 	}
256 	m->m_pkthdr.len = len;
257 	m->m_pkthdr.rcvif = NULL;
258 	m_copyback(m, 0, len, (caddr_t)msg);
259 
260 	/* avoid duplicated statistics */
261 	V_pfkeystat.in_total--;
262 	V_pfkeystat.in_bytes -= len;
263 	V_pfkeystat.in_msgtype[msg->sadb_msg_type]--;
264 
265 	return key_sendup_mbuf(so, m, target);
266 }
267 
268 /* so can be NULL if target != KEY_SENDUP_ONE */
269 int
270 key_sendup_mbuf(so, m, target)
271 	struct socket *so;
272 	struct mbuf *m;
273 	int target;
274 {
275 	INIT_VNET_NET(curvnet);
276 	INIT_VNET_IPSEC(curvnet);
277 	struct mbuf *n;
278 	struct keycb *kp;
279 	int sendup;
280 	struct rawcb *rp;
281 	int error = 0;
282 
283 	if (m == NULL)
284 		panic("key_sendup_mbuf: NULL pointer was passed.\n");
285 	if (so == NULL && target == KEY_SENDUP_ONE)
286 		panic("%s: NULL pointer was passed.\n", __func__);
287 
288 	V_pfkeystat.in_total++;
289 	V_pfkeystat.in_bytes += m->m_pkthdr.len;
290 	if (m->m_len < sizeof(struct sadb_msg)) {
291 		m = m_pullup(m, sizeof(struct sadb_msg));
292 		if (m == NULL) {
293 			V_pfkeystat.in_nomem++;
294 			return ENOBUFS;
295 		}
296 	}
297 	if (m->m_len >= sizeof(struct sadb_msg)) {
298 		struct sadb_msg *msg;
299 		msg = mtod(m, struct sadb_msg *);
300 		V_pfkeystat.in_msgtype[msg->sadb_msg_type]++;
301 	}
302 	mtx_lock(&rawcb_mtx);
303 	LIST_FOREACH(rp, &V_rawcb_list, list)
304 	{
305 		if (rp->rcb_proto.sp_family != PF_KEY)
306 			continue;
307 		if (rp->rcb_proto.sp_protocol
308 		 && rp->rcb_proto.sp_protocol != PF_KEY_V2) {
309 			continue;
310 		}
311 
312 		kp = (struct keycb *)rp;
313 
314 		/*
315 		 * If you are in promiscuous mode, and when you get broadcasted
316 		 * reply, you'll get two PF_KEY messages.
317 		 * (based on pf_key@inner.net message on 14 Oct 1998)
318 		 */
319 		if (((struct keycb *)rp)->kp_promisc) {
320 			if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
321 				(void)key_sendup0(rp, n, 1);
322 				n = NULL;
323 			}
324 		}
325 
326 		/* the exact target will be processed later */
327 		if (so && sotorawcb(so) == rp)
328 			continue;
329 
330 		sendup = 0;
331 		switch (target) {
332 		case KEY_SENDUP_ONE:
333 			/* the statement has no effect */
334 			if (so && sotorawcb(so) == rp)
335 				sendup++;
336 			break;
337 		case KEY_SENDUP_ALL:
338 			sendup++;
339 			break;
340 		case KEY_SENDUP_REGISTERED:
341 			if (kp->kp_registered)
342 				sendup++;
343 			break;
344 		}
345 		V_pfkeystat.in_msgtarget[target]++;
346 
347 		if (!sendup)
348 			continue;
349 
350 		if ((n = m_copy(m, 0, (int)M_COPYALL)) == NULL) {
351 			m_freem(m);
352 			V_pfkeystat.in_nomem++;
353 			mtx_unlock(&rawcb_mtx);
354 			return ENOBUFS;
355 		}
356 
357 		if ((error = key_sendup0(rp, n, 0)) != 0) {
358 			m_freem(m);
359 			mtx_unlock(&rawcb_mtx);
360 			return error;
361 		}
362 
363 		n = NULL;
364 	}
365 
366 	if (so) {
367 		error = key_sendup0(sotorawcb(so), m, 0);
368 		m = NULL;
369 	} else {
370 		error = 0;
371 		m_freem(m);
372 	}
373 	mtx_unlock(&rawcb_mtx);
374 	return error;
375 }
376 
377 /*
378  * key_abort()
379  * derived from net/rtsock.c:rts_abort()
380  */
381 static void
382 key_abort(struct socket *so)
383 {
384 	raw_usrreqs.pru_abort(so);
385 }
386 
387 /*
388  * key_attach()
389  * derived from net/rtsock.c:rts_attach()
390  */
391 static int
392 key_attach(struct socket *so, int proto, struct thread *td)
393 {
394 	INIT_VNET_IPSEC(curvnet);
395 	struct keycb *kp;
396 	int error;
397 
398 	KASSERT(so->so_pcb == NULL, ("key_attach: so_pcb != NULL"));
399 
400 	if (td != NULL) {
401 		error = priv_check(td, PRIV_NET_RAW);
402 		if (error)
403 			return error;
404 	}
405 
406 	/* XXX */
407 	kp = malloc(sizeof *kp, M_PCB, M_WAITOK | M_ZERO);
408 	if (kp == 0)
409 		return ENOBUFS;
410 
411 	so->so_pcb = (caddr_t)kp;
412 	error = raw_attach(so, proto);
413 	kp = (struct keycb *)sotorawcb(so);
414 	if (error) {
415 		free(kp, M_PCB);
416 		so->so_pcb = (caddr_t) 0;
417 		return error;
418 	}
419 
420 	kp->kp_promisc = kp->kp_registered = 0;
421 
422 	if (kp->kp_raw.rcb_proto.sp_protocol == PF_KEY) /* XXX: AF_KEY */
423 		V_key_cb.key_count++;
424 	V_key_cb.any_count++;
425 	soisconnected(so);
426 	so->so_options |= SO_USELOOPBACK;
427 
428 	return 0;
429 }
430 
431 /*
432  * key_bind()
433  * derived from net/rtsock.c:rts_bind()
434  */
435 static int
436 key_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
437 {
438   return EINVAL;
439 }
440 
441 /*
442  * key_close()
443  * derived from net/rtsock.c:rts_close().
444  */
445 static void
446 key_close(struct socket *so)
447 {
448 
449 	raw_usrreqs.pru_close(so);
450 }
451 
452 /*
453  * key_connect()
454  * derived from net/rtsock.c:rts_connect()
455  */
456 static int
457 key_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
458 {
459 	return EINVAL;
460 }
461 
462 /*
463  * key_detach()
464  * derived from net/rtsock.c:rts_detach()
465  */
466 static void
467 key_detach(struct socket *so)
468 {
469 	INIT_VNET_IPSEC(curvnet);
470 	struct keycb *kp = (struct keycb *)sotorawcb(so);
471 
472 	KASSERT(kp != NULL, ("key_detach: kp == NULL"));
473 	if (kp->kp_raw.rcb_proto.sp_protocol
474 	    == PF_KEY) /* XXX: AF_KEY */
475 		V_key_cb.key_count--;
476 	V_key_cb.any_count--;
477 
478 	key_freereg(so);
479 	raw_usrreqs.pru_detach(so);
480 }
481 
482 /*
483  * key_disconnect()
484  * derived from net/rtsock.c:key_disconnect()
485  */
486 static int
487 key_disconnect(struct socket *so)
488 {
489 	return(raw_usrreqs.pru_disconnect(so));
490 }
491 
492 /*
493  * key_peeraddr()
494  * derived from net/rtsock.c:rts_peeraddr()
495  */
496 static int
497 key_peeraddr(struct socket *so, struct sockaddr **nam)
498 {
499 	return(raw_usrreqs.pru_peeraddr(so, nam));
500 }
501 
502 /*
503  * key_send()
504  * derived from net/rtsock.c:rts_send()
505  */
506 static int
507 key_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
508 	 struct mbuf *control, struct thread *td)
509 {
510 	return(raw_usrreqs.pru_send(so, flags, m, nam, control, td));
511 }
512 
513 /*
514  * key_shutdown()
515  * derived from net/rtsock.c:rts_shutdown()
516  */
517 static int
518 key_shutdown(struct socket *so)
519 {
520 	return(raw_usrreqs.pru_shutdown(so));
521 }
522 
523 /*
524  * key_sockaddr()
525  * derived from net/rtsock.c:rts_sockaddr()
526  */
527 static int
528 key_sockaddr(struct socket *so, struct sockaddr **nam)
529 {
530 	return(raw_usrreqs.pru_sockaddr(so, nam));
531 }
532 
533 struct pr_usrreqs key_usrreqs = {
534 	.pru_abort =		key_abort,
535 	.pru_attach =		key_attach,
536 	.pru_bind =		key_bind,
537 	.pru_connect =		key_connect,
538 	.pru_detach =		key_detach,
539 	.pru_disconnect =	key_disconnect,
540 	.pru_peeraddr =		key_peeraddr,
541 	.pru_send =		key_send,
542 	.pru_shutdown =		key_shutdown,
543 	.pru_sockaddr =		key_sockaddr,
544 	.pru_close =		key_close,
545 };
546 
547 /* sysctl */
548 SYSCTL_NODE(_net, PF_KEY, key, CTLFLAG_RW, 0, "Key Family");
549 
550 /*
551  * Definitions of protocols supported in the KEY domain.
552  */
553 
554 extern struct domain keydomain;
555 
556 struct protosw keysw[] = {
557 {
558 	.pr_type =		SOCK_RAW,
559 	.pr_domain =		&keydomain,
560 	.pr_protocol =		PF_KEY_V2,
561 	.pr_flags =		PR_ATOMIC|PR_ADDR,
562 	.pr_output =		key_output,
563 	.pr_ctlinput =		raw_ctlinput,
564 	.pr_init =		raw_init,
565 	.pr_usrreqs =		&key_usrreqs
566 }
567 };
568 
569 static void
570 key_init0(void)
571 {
572 	INIT_VNET_IPSEC(curvnet);
573 	bzero((caddr_t)&V_key_cb, sizeof(V_key_cb));
574 	key_init();
575 }
576 
577 struct domain keydomain = {
578 	.dom_family =		PF_KEY,
579 	.dom_name =		"key",
580 	.dom_init =		key_init0,
581 	.dom_protosw =		keysw,
582 	.dom_protoswNPROTOSW =	&keysw[sizeof(keysw)/sizeof(keysw[0])]
583 };
584 
585 DOMAIN_SET(key);
586