xref: /freebsd/sys/netipsec/keysock.c (revision 09d325677d53a12c79a43664ff29871e92247629)
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 
54 #include <net/if.h>
55 #include <net/vnet.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 VNET_DEFINE(struct key_cb, key_cb);
74 #define	V_key_cb		VNET(key_cb)
75 
76 static struct sockaddr key_src = { 2, PF_KEY, };
77 
78 static int key_sendup0 __P((struct rawcb *, struct mbuf *, int));
79 
80 VNET_PCPUSTAT_DEFINE(struct pfkeystat, pfkeystat);
81 VNET_PCPUSTAT_SYSINIT(pfkeystat);
82 
83 #ifdef VIMAGE
84 VNET_PCPUSTAT_SYSUNINIT(pfkeystat);
85 #endif /* VIMAGE */
86 
87 /*
88  * key_output()
89  */
90 int
91 key_output(struct mbuf *m, struct socket *so)
92 {
93 	struct sadb_msg *msg;
94 	int len, error = 0;
95 
96 	if (m == 0)
97 		panic("%s: NULL pointer was passed.\n", __func__);
98 
99 	PFKEYSTAT_INC(out_total);
100 	PFKEYSTAT_ADD(out_bytes, m->m_pkthdr.len);
101 
102 	len = m->m_pkthdr.len;
103 	if (len < sizeof(struct sadb_msg)) {
104 		PFKEYSTAT_INC(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_INC(out_nomem);
112 			error = ENOBUFS;
113 			goto end;
114 		}
115 	}
116 
117 	M_ASSERTPKTHDR(m);
118 
119 	KEYDEBUG(KEYDEBUG_KEY_DUMP, kdebug_mbuf(m));
120 
121 	msg = mtod(m, struct sadb_msg *);
122 	PFKEYSTAT_INC(out_msgtype[msg->sadb_msg_type]);
123 	if (len != PFKEY_UNUNIT64(msg->sadb_msg_len)) {
124 		PFKEYSTAT_INC(out_invlen);
125 		error = EINVAL;
126 		goto end;
127 	}
128 
129 	error = key_parse(m, so);
130 	m = NULL;
131 end:
132 	if (m)
133 		m_freem(m);
134 	return error;
135 }
136 
137 /*
138  * send message to the socket.
139  */
140 static int
141 key_sendup0(rp, m, promisc)
142 	struct rawcb *rp;
143 	struct mbuf *m;
144 	int promisc;
145 {
146 	int error;
147 
148 	if (promisc) {
149 		struct sadb_msg *pmsg;
150 
151 		M_PREPEND(m, sizeof(struct sadb_msg), M_NOWAIT);
152 		if (m && m->m_len < sizeof(struct sadb_msg))
153 			m = m_pullup(m, sizeof(struct sadb_msg));
154 		if (!m) {
155 			PFKEYSTAT_INC(in_nomem);
156 			m_freem(m);
157 			return ENOBUFS;
158 		}
159 		m->m_pkthdr.len += sizeof(*pmsg);
160 
161 		pmsg = mtod(m, struct sadb_msg *);
162 		bzero(pmsg, sizeof(*pmsg));
163 		pmsg->sadb_msg_version = PF_KEY_V2;
164 		pmsg->sadb_msg_type = SADB_X_PROMISC;
165 		pmsg->sadb_msg_len = PFKEY_UNIT64(m->m_pkthdr.len);
166 		/* pid and seq? */
167 
168 		PFKEYSTAT_INC(in_msgtype[pmsg->sadb_msg_type]);
169 	}
170 
171 	if (!sbappendaddr(&rp->rcb_socket->so_rcv, (struct sockaddr *)&key_src,
172 	    m, NULL)) {
173 		PFKEYSTAT_INC(in_nomem);
174 		m_freem(m);
175 		error = ENOBUFS;
176 	} else
177 		error = 0;
178 	sorwakeup(rp->rcb_socket);
179 	return error;
180 }
181 
182 /* XXX this interface should be obsoleted. */
183 int
184 key_sendup(so, msg, len, target)
185 	struct socket *so;
186 	struct sadb_msg *msg;
187 	u_int len;
188 	int target;	/*target of the resulting message*/
189 {
190 	struct mbuf *m, *n, *mprev;
191 	int tlen;
192 
193 	/* sanity check */
194 	if (so == 0 || msg == 0)
195 		panic("%s: NULL pointer was passed.\n", __func__);
196 
197 	KEYDEBUG(KEYDEBUG_KEY_DUMP,
198 		printf("%s: \n", __func__);
199 		kdebug_sadb(msg));
200 
201 	/*
202 	 * we increment statistics here, just in case we have ENOBUFS
203 	 * in this function.
204 	 */
205 	PFKEYSTAT_INC(in_total);
206 	PFKEYSTAT_ADD(in_bytes, len);
207 	PFKEYSTAT_INC(in_msgtype[msg->sadb_msg_type]);
208 
209 	/*
210 	 * Get mbuf chain whenever possible (not clusters),
211 	 * to save socket buffer.  We'll be generating many SADB_ACQUIRE
212 	 * messages to listening key sockets.  If we simply allocate clusters,
213 	 * sbappendaddr() will raise ENOBUFS due to too little sbspace().
214 	 * sbspace() computes # of actual data bytes AND mbuf region.
215 	 *
216 	 * TODO: SADB_ACQUIRE filters should be implemented.
217 	 */
218 	tlen = len;
219 	m = mprev = NULL;
220 	while (tlen > 0) {
221 		if (tlen == len) {
222 			MGETHDR(n, M_NOWAIT, MT_DATA);
223 			if (n == NULL) {
224 				PFKEYSTAT_INC(in_nomem);
225 				return ENOBUFS;
226 			}
227 			n->m_len = MHLEN;
228 		} else {
229 			MGET(n, M_NOWAIT, MT_DATA);
230 			if (n == NULL) {
231 				PFKEYSTAT_INC(in_nomem);
232 				return ENOBUFS;
233 			}
234 			n->m_len = MLEN;
235 		}
236 		if (tlen >= MCLBYTES) {	/*XXX better threshold? */
237 			MCLGET(n, M_NOWAIT);
238 			if ((n->m_flags & M_EXT) == 0) {
239 				m_free(n);
240 				m_freem(m);
241 				PFKEYSTAT_INC(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_ADD(in_total, -1);
265 	PFKEYSTAT_ADD(in_bytes, -len);
266 	PFKEYSTAT_ADD(in_msgtype[msg->sadb_msg_type], -1);
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("%s: NULL pointer was passed.\n", __func__);
288 
289 	PFKEYSTAT_INC(in_total);
290 	PFKEYSTAT_ADD(in_bytes, m->m_pkthdr.len);
291 	if (m->m_len < sizeof(struct sadb_msg)) {
292 		m = m_pullup(m, sizeof(struct sadb_msg));
293 		if (m == NULL) {
294 			PFKEYSTAT_INC(in_nomem);
295 			return ENOBUFS;
296 		}
297 	}
298 	if (m->m_len >= sizeof(struct sadb_msg)) {
299 		struct sadb_msg *msg;
300 		msg = mtod(m, struct sadb_msg *);
301 		PFKEYSTAT_INC(in_msgtype[msg->sadb_msg_type]);
302 	}
303 	mtx_lock(&rawcb_mtx);
304 	LIST_FOREACH(rp, &V_rawcb_list, list)
305 	{
306 		if (rp->rcb_proto.sp_family != PF_KEY)
307 			continue;
308 		if (rp->rcb_proto.sp_protocol
309 		 && rp->rcb_proto.sp_protocol != PF_KEY_V2) {
310 			continue;
311 		}
312 
313 		kp = (struct keycb *)rp;
314 
315 		/*
316 		 * If you are in promiscuous mode, and when you get broadcasted
317 		 * reply, you'll get two PF_KEY messages.
318 		 * (based on pf_key@inner.net message on 14 Oct 1998)
319 		 */
320 		if (((struct keycb *)rp)->kp_promisc) {
321 			if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
322 				(void)key_sendup0(rp, n, 1);
323 				n = NULL;
324 			}
325 		}
326 
327 		/* the exact target will be processed later */
328 		if (so && sotorawcb(so) == rp)
329 			continue;
330 
331 		sendup = 0;
332 		switch (target) {
333 		case KEY_SENDUP_ONE:
334 			/* the statement has no effect */
335 			if (so && sotorawcb(so) == rp)
336 				sendup++;
337 			break;
338 		case KEY_SENDUP_ALL:
339 			sendup++;
340 			break;
341 		case KEY_SENDUP_REGISTERED:
342 			if (kp->kp_registered)
343 				sendup++;
344 			break;
345 		}
346 		PFKEYSTAT_INC(in_msgtarget[target]);
347 
348 		if (!sendup)
349 			continue;
350 
351 		if ((n = m_copy(m, 0, (int)M_COPYALL)) == NULL) {
352 			m_freem(m);
353 			PFKEYSTAT_INC(in_nomem);
354 			mtx_unlock(&rawcb_mtx);
355 			return ENOBUFS;
356 		}
357 
358 		if ((error = key_sendup0(rp, n, 0)) != 0) {
359 			m_freem(m);
360 			mtx_unlock(&rawcb_mtx);
361 			return error;
362 		}
363 
364 		n = NULL;
365 	}
366 
367 	if (so) {
368 		error = key_sendup0(sotorawcb(so), m, 0);
369 		m = NULL;
370 	} else {
371 		error = 0;
372 		m_freem(m);
373 	}
374 	mtx_unlock(&rawcb_mtx);
375 	return error;
376 }
377 
378 /*
379  * key_abort()
380  * derived from net/rtsock.c:rts_abort()
381  */
382 static void
383 key_abort(struct socket *so)
384 {
385 	raw_usrreqs.pru_abort(so);
386 }
387 
388 /*
389  * key_attach()
390  * derived from net/rtsock.c:rts_attach()
391  */
392 static int
393 key_attach(struct socket *so, int proto, struct thread *td)
394 {
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 	struct keycb *kp = (struct keycb *)sotorawcb(so);
470 
471 	KASSERT(kp != NULL, ("key_detach: kp == NULL"));
472 	if (kp->kp_raw.rcb_proto.sp_protocol
473 	    == PF_KEY) /* XXX: AF_KEY */
474 		V_key_cb.key_count--;
475 	V_key_cb.any_count--;
476 
477 	key_freereg(so);
478 	raw_usrreqs.pru_detach(so);
479 }
480 
481 /*
482  * key_disconnect()
483  * derived from net/rtsock.c:key_disconnect()
484  */
485 static int
486 key_disconnect(struct socket *so)
487 {
488 	return(raw_usrreqs.pru_disconnect(so));
489 }
490 
491 /*
492  * key_peeraddr()
493  * derived from net/rtsock.c:rts_peeraddr()
494  */
495 static int
496 key_peeraddr(struct socket *so, struct sockaddr **nam)
497 {
498 	return(raw_usrreqs.pru_peeraddr(so, nam));
499 }
500 
501 /*
502  * key_send()
503  * derived from net/rtsock.c:rts_send()
504  */
505 static int
506 key_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
507 	 struct mbuf *control, struct thread *td)
508 {
509 	return(raw_usrreqs.pru_send(so, flags, m, nam, control, td));
510 }
511 
512 /*
513  * key_shutdown()
514  * derived from net/rtsock.c:rts_shutdown()
515  */
516 static int
517 key_shutdown(struct socket *so)
518 {
519 	return(raw_usrreqs.pru_shutdown(so));
520 }
521 
522 /*
523  * key_sockaddr()
524  * derived from net/rtsock.c:rts_sockaddr()
525  */
526 static int
527 key_sockaddr(struct socket *so, struct sockaddr **nam)
528 {
529 	return(raw_usrreqs.pru_sockaddr(so, nam));
530 }
531 
532 struct pr_usrreqs key_usrreqs = {
533 	.pru_abort =		key_abort,
534 	.pru_attach =		key_attach,
535 	.pru_bind =		key_bind,
536 	.pru_connect =		key_connect,
537 	.pru_detach =		key_detach,
538 	.pru_disconnect =	key_disconnect,
539 	.pru_peeraddr =		key_peeraddr,
540 	.pru_send =		key_send,
541 	.pru_shutdown =		key_shutdown,
542 	.pru_sockaddr =		key_sockaddr,
543 	.pru_close =		key_close,
544 };
545 
546 /* sysctl */
547 SYSCTL_NODE(_net, PF_KEY, key, CTLFLAG_RW, 0, "Key Family");
548 
549 /*
550  * Definitions of protocols supported in the KEY domain.
551  */
552 
553 extern struct domain keydomain;
554 
555 struct protosw keysw[] = {
556 {
557 	.pr_type =		SOCK_RAW,
558 	.pr_domain =		&keydomain,
559 	.pr_protocol =		PF_KEY_V2,
560 	.pr_flags =		PR_ATOMIC|PR_ADDR,
561 	.pr_output =		key_output,
562 	.pr_ctlinput =		raw_ctlinput,
563 	.pr_init =		raw_init,
564 	.pr_usrreqs =		&key_usrreqs
565 }
566 };
567 
568 static void
569 key_init0(void)
570 {
571 
572 	bzero((caddr_t)&V_key_cb, sizeof(V_key_cb));
573 	key_init();
574 }
575 
576 struct domain keydomain = {
577 	.dom_family =		PF_KEY,
578 	.dom_name =		"key",
579 	.dom_init =		key_init0,
580 #ifdef VIMAGE
581 	.dom_destroy =		key_destroy,
582 #endif
583 	.dom_protosw =		keysw,
584 	.dom_protoswNPROTOSW =	&keysw[sizeof(keysw)/sizeof(keysw[0])]
585 };
586 
587 VNET_DOMAIN_SET(key);
588