keysock.c revision 330897 
1/*	$FreeBSD: stable/11/sys/netipsec/keysock.c 330897 2018-03-14 03:19:51Z eadler $	*/
2/*	$KAME: keysock.c,v 1.25 2001/08/13 20:07:41 itojun Exp $	*/
3
4/*-
5 * SPDX-License-Identifier: BSD-3-Clause
6 *
7 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the project nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#include "opt_ipsec.h"
36
37/* This code has derived from sys/net/rtsock.c on FreeBSD2.2.5 */
38
39#include <sys/types.h>
40#include <sys/param.h>
41#include <sys/domain.h>
42#include <sys/errno.h>
43#include <sys/kernel.h>
44#include <sys/lock.h>
45#include <sys/malloc.h>
46#include <sys/mbuf.h>
47#include <sys/mutex.h>
48#include <sys/priv.h>
49#include <sys/protosw.h>
50#include <sys/signalvar.h>
51#include <sys/socket.h>
52#include <sys/socketvar.h>
53#include <sys/sysctl.h>
54#include <sys/systm.h>
55
56#include <net/if.h>
57#include <net/vnet.h>
58#include <net/raw_cb.h>
59
60#include <netinet/in.h>
61
62#include <net/pfkeyv2.h>
63#include <netipsec/key.h>
64#include <netipsec/keysock.h>
65#include <netipsec/key_debug.h>
66#include <netipsec/ipsec.h>
67
68#include <machine/stdarg.h>
69
70struct key_cb {
71	int key_count;
72	int any_count;
73};
74static VNET_DEFINE(struct key_cb, key_cb);
75#define	V_key_cb		VNET(key_cb)
76
77static struct sockaddr key_src = { 2, PF_KEY, };
78
79static int key_sendup0(struct rawcb *, struct mbuf *, int);
80
81VNET_PCPUSTAT_DEFINE(struct pfkeystat, pfkeystat);
82VNET_PCPUSTAT_SYSINIT(pfkeystat);
83
84#ifdef VIMAGE
85VNET_PCPUSTAT_SYSUNINIT(pfkeystat);
86#endif /* VIMAGE */
87
88/*
89 * key_output()
90 */
91int
92key_output(struct mbuf *m, struct socket *so, ...)
93{
94	struct sadb_msg *msg;
95	int len, error = 0;
96
97	if (m == NULL)
98		panic("%s: NULL pointer was passed.\n", __func__);
99
100	PFKEYSTAT_INC(out_total);
101	PFKEYSTAT_ADD(out_bytes, m->m_pkthdr.len);
102
103	len = m->m_pkthdr.len;
104	if (len < sizeof(struct sadb_msg)) {
105		PFKEYSTAT_INC(out_tooshort);
106		error = EINVAL;
107		goto end;
108	}
109
110	if (m->m_len < sizeof(struct sadb_msg)) {
111		if ((m = m_pullup(m, sizeof(struct sadb_msg))) == NULL) {
112			PFKEYSTAT_INC(out_nomem);
113			error = ENOBUFS;
114			goto end;
115		}
116	}
117
118	M_ASSERTPKTHDR(m);
119
120	KEYDBG(KEY_DUMP, kdebug_mbuf(m));
121
122	msg = mtod(m, struct sadb_msg *);
123	PFKEYSTAT_INC(out_msgtype[msg->sadb_msg_type]);
124	if (len != PFKEY_UNUNIT64(msg->sadb_msg_len)) {
125		PFKEYSTAT_INC(out_invlen);
126		error = EINVAL;
127		goto end;
128	}
129
130	error = key_parse(m, so);
131	m = NULL;
132end:
133	if (m)
134		m_freem(m);
135	return error;
136}
137
138/*
139 * send message to the socket.
140 */
141static int
142key_sendup0(struct rawcb *rp, struct mbuf *m, int promisc)
143{
144	int error;
145
146	if (promisc) {
147		struct sadb_msg *pmsg;
148
149		M_PREPEND(m, sizeof(struct sadb_msg), M_NOWAIT);
150		if (m == NULL) {
151			PFKEYSTAT_INC(in_nomem);
152			return (ENOBUFS);
153		}
154		pmsg = mtod(m, struct sadb_msg *);
155		bzero(pmsg, sizeof(*pmsg));
156		pmsg->sadb_msg_version = PF_KEY_V2;
157		pmsg->sadb_msg_type = SADB_X_PROMISC;
158		pmsg->sadb_msg_len = PFKEY_UNIT64(m->m_pkthdr.len);
159		/* pid and seq? */
160
161		PFKEYSTAT_INC(in_msgtype[pmsg->sadb_msg_type]);
162	}
163
164	if (!sbappendaddr(&rp->rcb_socket->so_rcv, (struct sockaddr *)&key_src,
165	    m, NULL)) {
166		PFKEYSTAT_INC(in_nomem);
167		m_freem(m);
168		error = ENOBUFS;
169	} else
170		error = 0;
171	sorwakeup(rp->rcb_socket);
172	return error;
173}
174
175/* XXX this interface should be obsoleted. */
176int
177key_sendup(struct socket *so, struct sadb_msg *msg, u_int len, int target)
178{
179	struct mbuf *m, *n, *mprev;
180	int tlen;
181
182	/* sanity check */
183	if (so == NULL || msg == NULL)
184		panic("%s: NULL pointer was passed.\n", __func__);
185
186	KEYDBG(KEY_DUMP,
187	    printf("%s: \n", __func__);
188	    kdebug_sadb(msg));
189
190	/*
191	 * we increment statistics here, just in case we have ENOBUFS
192	 * in this function.
193	 */
194	PFKEYSTAT_INC(in_total);
195	PFKEYSTAT_ADD(in_bytes, len);
196	PFKEYSTAT_INC(in_msgtype[msg->sadb_msg_type]);
197
198	/*
199	 * Get mbuf chain whenever possible (not clusters),
200	 * to save socket buffer.  We'll be generating many SADB_ACQUIRE
201	 * messages to listening key sockets.  If we simply allocate clusters,
202	 * sbappendaddr() will raise ENOBUFS due to too little sbspace().
203	 * sbspace() computes # of actual data bytes AND mbuf region.
204	 *
205	 * TODO: SADB_ACQUIRE filters should be implemented.
206	 */
207	tlen = len;
208	m = mprev = NULL;
209	while (tlen > 0) {
210		if (tlen == len) {
211			MGETHDR(n, M_NOWAIT, MT_DATA);
212			if (n == NULL) {
213				PFKEYSTAT_INC(in_nomem);
214				return ENOBUFS;
215			}
216			n->m_len = MHLEN;
217		} else {
218			MGET(n, M_NOWAIT, MT_DATA);
219			if (n == NULL) {
220				PFKEYSTAT_INC(in_nomem);
221				return ENOBUFS;
222			}
223			n->m_len = MLEN;
224		}
225		if (tlen >= MCLBYTES) {	/*XXX better threshold? */
226			if (!(MCLGET(n, M_NOWAIT))) {
227				m_free(n);
228				m_freem(m);
229				PFKEYSTAT_INC(in_nomem);
230				return ENOBUFS;
231			}
232			n->m_len = MCLBYTES;
233		}
234
235		if (tlen < n->m_len)
236			n->m_len = tlen;
237		n->m_next = NULL;
238		if (m == NULL)
239			m = mprev = n;
240		else {
241			mprev->m_next = n;
242			mprev = n;
243		}
244		tlen -= n->m_len;
245		n = NULL;
246	}
247	m->m_pkthdr.len = len;
248	m->m_pkthdr.rcvif = NULL;
249	m_copyback(m, 0, len, (caddr_t)msg);
250
251	/* avoid duplicated statistics */
252	PFKEYSTAT_ADD(in_total, -1);
253	PFKEYSTAT_ADD(in_bytes, -len);
254	PFKEYSTAT_ADD(in_msgtype[msg->sadb_msg_type], -1);
255
256	return key_sendup_mbuf(so, m, target);
257}
258
259/* so can be NULL if target != KEY_SENDUP_ONE */
260int
261key_sendup_mbuf(struct socket *so, struct mbuf *m, int target)
262{
263	struct mbuf *n;
264	struct keycb *kp;
265	int sendup;
266	struct rawcb *rp;
267	int error = 0;
268
269	if (m == NULL)
270		panic("key_sendup_mbuf: NULL pointer was passed.\n");
271	if (so == NULL && target == KEY_SENDUP_ONE)
272		panic("%s: NULL pointer was passed.\n", __func__);
273
274	PFKEYSTAT_INC(in_total);
275	PFKEYSTAT_ADD(in_bytes, m->m_pkthdr.len);
276	if (m->m_len < sizeof(struct sadb_msg)) {
277		m = m_pullup(m, sizeof(struct sadb_msg));
278		if (m == NULL) {
279			PFKEYSTAT_INC(in_nomem);
280			return ENOBUFS;
281		}
282	}
283	if (m->m_len >= sizeof(struct sadb_msg)) {
284		struct sadb_msg *msg;
285		msg = mtod(m, struct sadb_msg *);
286		PFKEYSTAT_INC(in_msgtype[msg->sadb_msg_type]);
287	}
288	mtx_lock(&rawcb_mtx);
289	LIST_FOREACH(rp, &V_rawcb_list, list)
290	{
291		if (rp->rcb_proto.sp_family != PF_KEY)
292			continue;
293		if (rp->rcb_proto.sp_protocol
294		 && rp->rcb_proto.sp_protocol != PF_KEY_V2) {
295			continue;
296		}
297
298		kp = (struct keycb *)rp;
299
300		/*
301		 * If you are in promiscuous mode, and when you get broadcasted
302		 * reply, you'll get two PF_KEY messages.
303		 * (based on pf_key@inner.net message on 14 Oct 1998)
304		 */
305		if (((struct keycb *)rp)->kp_promisc) {
306			if ((n = m_copy(m, 0, (int)M_COPYALL)) != NULL) {
307				(void)key_sendup0(rp, n, 1);
308				n = NULL;
309			}
310		}
311
312		/* the exact target will be processed later */
313		if (so && sotorawcb(so) == rp)
314			continue;
315
316		sendup = 0;
317		switch (target) {
318		case KEY_SENDUP_ONE:
319			/* the statement has no effect */
320			if (so && sotorawcb(so) == rp)
321				sendup++;
322			break;
323		case KEY_SENDUP_ALL:
324			sendup++;
325			break;
326		case KEY_SENDUP_REGISTERED:
327			if (kp->kp_registered)
328				sendup++;
329			break;
330		}
331		PFKEYSTAT_INC(in_msgtarget[target]);
332
333		if (!sendup)
334			continue;
335
336		if ((n = m_copy(m, 0, (int)M_COPYALL)) == NULL) {
337			m_freem(m);
338			PFKEYSTAT_INC(in_nomem);
339			mtx_unlock(&rawcb_mtx);
340			return ENOBUFS;
341		}
342
343		if ((error = key_sendup0(rp, n, 0)) != 0) {
344			m_freem(m);
345			mtx_unlock(&rawcb_mtx);
346			return error;
347		}
348
349		n = NULL;
350	}
351
352	if (so) {
353		error = key_sendup0(sotorawcb(so), m, 0);
354		m = NULL;
355	} else {
356		error = 0;
357		m_freem(m);
358	}
359	mtx_unlock(&rawcb_mtx);
360	return error;
361}
362
363/*
364 * key_abort()
365 * derived from net/rtsock.c:rts_abort()
366 */
367static void
368key_abort(struct socket *so)
369{
370	raw_usrreqs.pru_abort(so);
371}
372
373/*
374 * key_attach()
375 * derived from net/rtsock.c:rts_attach()
376 */
377static int
378key_attach(struct socket *so, int proto, struct thread *td)
379{
380	struct keycb *kp;
381	int error;
382
383	KASSERT(so->so_pcb == NULL, ("key_attach: so_pcb != NULL"));
384
385	if (td != NULL) {
386		error = priv_check(td, PRIV_NET_RAW);
387		if (error)
388			return error;
389	}
390
391	/* XXX */
392	kp = malloc(sizeof *kp, M_PCB, M_WAITOK | M_ZERO);
393	if (kp == NULL)
394		return ENOBUFS;
395
396	so->so_pcb = (caddr_t)kp;
397	error = raw_attach(so, proto);
398	kp = (struct keycb *)sotorawcb(so);
399	if (error) {
400		free(kp, M_PCB);
401		so->so_pcb = (caddr_t) 0;
402		return error;
403	}
404
405	kp->kp_promisc = kp->kp_registered = 0;
406
407	if (kp->kp_raw.rcb_proto.sp_protocol == PF_KEY) /* XXX: AF_KEY */
408		V_key_cb.key_count++;
409	V_key_cb.any_count++;
410	soisconnected(so);
411	so->so_options |= SO_USELOOPBACK;
412
413	return 0;
414}
415
416/*
417 * key_bind()
418 * derived from net/rtsock.c:rts_bind()
419 */
420static int
421key_bind(struct socket *so, struct sockaddr *nam, struct thread *td)
422{
423  return EINVAL;
424}
425
426/*
427 * key_close()
428 * derived from net/rtsock.c:rts_close().
429 */
430static void
431key_close(struct socket *so)
432{
433
434	raw_usrreqs.pru_close(so);
435}
436
437/*
438 * key_connect()
439 * derived from net/rtsock.c:rts_connect()
440 */
441static int
442key_connect(struct socket *so, struct sockaddr *nam, struct thread *td)
443{
444	return EINVAL;
445}
446
447/*
448 * key_detach()
449 * derived from net/rtsock.c:rts_detach()
450 */
451static void
452key_detach(struct socket *so)
453{
454	struct keycb *kp = (struct keycb *)sotorawcb(so);
455
456	KASSERT(kp != NULL, ("key_detach: kp == NULL"));
457	if (kp->kp_raw.rcb_proto.sp_protocol
458	    == PF_KEY) /* XXX: AF_KEY */
459		V_key_cb.key_count--;
460	V_key_cb.any_count--;
461
462	key_freereg(so);
463	raw_usrreqs.pru_detach(so);
464}
465
466/*
467 * key_disconnect()
468 * derived from net/rtsock.c:key_disconnect()
469 */
470static int
471key_disconnect(struct socket *so)
472{
473	return(raw_usrreqs.pru_disconnect(so));
474}
475
476/*
477 * key_peeraddr()
478 * derived from net/rtsock.c:rts_peeraddr()
479 */
480static int
481key_peeraddr(struct socket *so, struct sockaddr **nam)
482{
483	return(raw_usrreqs.pru_peeraddr(so, nam));
484}
485
486/*
487 * key_send()
488 * derived from net/rtsock.c:rts_send()
489 */
490static int
491key_send(struct socket *so, int flags, struct mbuf *m, struct sockaddr *nam,
492	 struct mbuf *control, struct thread *td)
493{
494	return(raw_usrreqs.pru_send(so, flags, m, nam, control, td));
495}
496
497/*
498 * key_shutdown()
499 * derived from net/rtsock.c:rts_shutdown()
500 */
501static int
502key_shutdown(struct socket *so)
503{
504	return(raw_usrreqs.pru_shutdown(so));
505}
506
507/*
508 * key_sockaddr()
509 * derived from net/rtsock.c:rts_sockaddr()
510 */
511static int
512key_sockaddr(struct socket *so, struct sockaddr **nam)
513{
514	return(raw_usrreqs.pru_sockaddr(so, nam));
515}
516
517struct pr_usrreqs key_usrreqs = {
518	.pru_abort =		key_abort,
519	.pru_attach =		key_attach,
520	.pru_bind =		key_bind,
521	.pru_connect =		key_connect,
522	.pru_detach =		key_detach,
523	.pru_disconnect =	key_disconnect,
524	.pru_peeraddr =		key_peeraddr,
525	.pru_send =		key_send,
526	.pru_shutdown =		key_shutdown,
527	.pru_sockaddr =		key_sockaddr,
528	.pru_close =		key_close,
529};
530
531/* sysctl */
532SYSCTL_NODE(_net, PF_KEY, key, CTLFLAG_RW, 0, "Key Family");
533
534/*
535 * Definitions of protocols supported in the KEY domain.
536 */
537
538extern struct domain keydomain;
539
540struct protosw keysw[] = {
541{
542	.pr_type =		SOCK_RAW,
543	.pr_domain =		&keydomain,
544	.pr_protocol =		PF_KEY_V2,
545	.pr_flags =		PR_ATOMIC|PR_ADDR,
546	.pr_output =		key_output,
547	.pr_ctlinput =		raw_ctlinput,
548	.pr_init =		raw_init,
549	.pr_usrreqs =		&key_usrreqs
550}
551};
552
553static void
554key_init0(void)
555{
556
557	bzero((caddr_t)&V_key_cb, sizeof(V_key_cb));
558	key_init();
559}
560
561struct domain keydomain = {
562	.dom_family =		PF_KEY,
563	.dom_name =		"key",
564	.dom_init =		key_init0,
565#ifdef VIMAGE
566	.dom_destroy =		key_destroy,
567#endif
568	.dom_protosw =		keysw,
569	.dom_protoswNPROTOSW =	&keysw[nitems(keysw)]
570};
571
572VNET_DOMAIN_SET(key);
573