xref: /freebsd/sys/netipsec/keysock.c (revision d5b0e70f7e04d971691517ce1304d86a1e367e2e)
1 /*	$FreeBSD$	*/
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 
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 static struct mtx keysock_mtx;
70 MTX_SYSINIT(keysock, &keysock_mtx, "key socket pcb list", MTX_DEF);
71 
72 #define	KEYSOCK_LOCK()		mtx_lock(&keysock_mtx)
73 #define	KEYSOCK_UNLOCK()	mtx_unlock(&keysock_mtx)
74 
75 VNET_DEFINE_STATIC(LIST_HEAD(, keycb), keycb_list) =
76     LIST_HEAD_INITIALIZER(keycb_list);
77 #define	V_keycb_list		VNET(keycb_list)
78 
79 static struct sockaddr key_src = { 2, PF_KEY, };
80 
81 static int key_sendup0(struct keycb *, struct mbuf *, int);
82 
83 VNET_PCPUSTAT_DEFINE(struct pfkeystat, pfkeystat);
84 VNET_PCPUSTAT_SYSINIT(pfkeystat);
85 
86 #ifdef VIMAGE
87 VNET_PCPUSTAT_SYSUNINIT(pfkeystat);
88 #endif /* VIMAGE */
89 
90 static int
91 key_send(struct socket *so, int flags, struct mbuf *m,
92     struct sockaddr *nam, struct mbuf *control, struct thread *td)
93 {
94 	struct sadb_msg *msg;
95 	int len, error = 0;
96 
97 	if ((flags & PRUS_OOB) || control != NULL) {
98 		m_freem(m);
99 		if (control != NULL)
100 			m_freem(control);
101 		return (EOPNOTSUPP);
102 	}
103 
104 	PFKEYSTAT_INC(out_total);
105 	PFKEYSTAT_ADD(out_bytes, m->m_pkthdr.len);
106 
107 	len = m->m_pkthdr.len;
108 	if (len < sizeof(struct sadb_msg)) {
109 		PFKEYSTAT_INC(out_tooshort);
110 		error = EINVAL;
111 		goto end;
112 	}
113 
114 	if (m->m_len < sizeof(struct sadb_msg)) {
115 		if ((m = m_pullup(m, sizeof(struct sadb_msg))) == NULL) {
116 			PFKEYSTAT_INC(out_nomem);
117 			error = ENOBUFS;
118 			goto end;
119 		}
120 	}
121 
122 	M_ASSERTPKTHDR(m);
123 
124 	KEYDBG(KEY_DUMP, kdebug_mbuf(m));
125 
126 	msg = mtod(m, struct sadb_msg *);
127 	PFKEYSTAT_INC(out_msgtype[msg->sadb_msg_type]);
128 	if (len != PFKEY_UNUNIT64(msg->sadb_msg_len)) {
129 		PFKEYSTAT_INC(out_invlen);
130 		error = EINVAL;
131 		goto end;
132 	}
133 
134 	error = key_parse(m, so);
135 	m = NULL;
136 end:
137 	if (m)
138 		m_freem(m);
139 	return error;
140 }
141 
142 /*
143  * send message to the socket.
144  */
145 static int
146 key_sendup0(struct keycb *kp, struct mbuf *m, int promisc)
147 {
148 
149 	if (promisc) {
150 		struct sadb_msg *pmsg;
151 
152 		M_PREPEND(m, sizeof(struct sadb_msg), M_NOWAIT);
153 		if (m == NULL) {
154 			PFKEYSTAT_INC(in_nomem);
155 			return (ENOBUFS);
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 		PFKEYSTAT_INC(in_msgtype[pmsg->sadb_msg_type]);
165 	}
166 
167 	if (!sbappendaddr(&kp->kp_socket->so_rcv, &key_src, m, NULL)) {
168 		PFKEYSTAT_INC(in_nomem);
169 		m_freem(m);
170 		soroverflow(kp->kp_socket);
171 		return ENOBUFS;
172 	}
173 
174 	sorwakeup(kp->kp_socket);
175 	return 0;
176 }
177 
178 /* so can be NULL if target != KEY_SENDUP_ONE */
179 int
180 key_sendup_mbuf(struct socket *so, struct mbuf *m, int target)
181 {
182 	struct mbuf *n;
183 	struct keycb *kp;
184 	int error = 0;
185 
186 	KASSERT(m != NULL, ("NULL mbuf pointer was passed."));
187 	KASSERT(so != NULL || target != KEY_SENDUP_ONE,
188 	    ("NULL socket pointer was passed."));
189 	KASSERT(target == KEY_SENDUP_ONE || target == KEY_SENDUP_ALL ||
190 	    target == KEY_SENDUP_REGISTERED, ("Wrong target %d", target));
191 
192 	PFKEYSTAT_INC(in_total);
193 	PFKEYSTAT_ADD(in_bytes, m->m_pkthdr.len);
194 	if (m->m_len < sizeof(struct sadb_msg)) {
195 		m = m_pullup(m, sizeof(struct sadb_msg));
196 		if (m == NULL) {
197 			PFKEYSTAT_INC(in_nomem);
198 			return ENOBUFS;
199 		}
200 	}
201 	if (m->m_len >= sizeof(struct sadb_msg)) {
202 		struct sadb_msg *msg;
203 		msg = mtod(m, struct sadb_msg *);
204 		PFKEYSTAT_INC(in_msgtype[msg->sadb_msg_type]);
205 	}
206 	KEYSOCK_LOCK();
207 	LIST_FOREACH(kp, &V_keycb_list, kp_next) {
208 		/*
209 		 * If you are in promiscuous mode, and when you get broadcasted
210 		 * reply, you'll get two PF_KEY messages.
211 		 * (based on pf_key@inner.net message on 14 Oct 1998)
212 		 */
213 		if (kp->kp_promisc) {
214 			n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
215 			if (n != NULL)
216 				key_sendup0(kp, n, 1);
217 			else
218 				PFKEYSTAT_INC(in_nomem);
219 		}
220 
221 		/* the exact target will be processed later */
222 		if (so != NULL && so->so_pcb == kp)
223 			continue;
224 
225 		if (target == KEY_SENDUP_ONE || (
226 		    target == KEY_SENDUP_REGISTERED && kp->kp_registered == 0))
227 			continue;
228 
229 		/* KEY_SENDUP_ALL + KEY_SENDUP_REGISTERED */
230 		n = m_copym(m, 0, M_COPYALL, M_NOWAIT);
231 		if (n == NULL) {
232 			PFKEYSTAT_INC(in_nomem);
233 			/* Try send to another socket */
234 			continue;
235 		}
236 
237 		if (key_sendup0(kp, n, 0) == 0)
238 			PFKEYSTAT_INC(in_msgtarget[target]);
239 	}
240 
241 	if (so)	{ /* KEY_SENDUP_ONE */
242 		error = key_sendup0(so->so_pcb, m, 0);
243 		if (error == 0)
244 			PFKEYSTAT_INC(in_msgtarget[KEY_SENDUP_ONE]);
245 	} else {
246 		error = 0;
247 		m_freem(m);
248 	}
249 	KEYSOCK_UNLOCK();
250 	return (error);
251 }
252 
253 static u_long key_sendspace = 8192;
254 SYSCTL_ULONG(_net_key, OID_AUTO, sendspace, CTLFLAG_RW, &key_sendspace, 0,
255     "Default key socket send space");
256 static u_long key_recvspace = 8192;
257 SYSCTL_ULONG(_net_key, OID_AUTO, recvspace, CTLFLAG_RW, &key_recvspace, 0,
258     "Default key socket receive space");
259 
260 static int
261 key_attach(struct socket *so, int proto, struct thread *td)
262 {
263 	struct keycb *kp;
264 	int error;
265 
266 	KASSERT(so->so_pcb == NULL, ("key_attach: so_pcb != NULL"));
267 
268 	if (td != NULL) {
269 		error = priv_check(td, PRIV_NET_RAW);
270 		if (error)
271 			return error;
272 	}
273 
274 	error = soreserve(so, key_sendspace, key_recvspace);
275 	if (error)
276 		return (error);
277 
278 	kp = malloc(sizeof(*kp), M_PCB, M_WAITOK);
279 	kp->kp_socket = so;
280 	kp->kp_promisc = kp->kp_registered = 0;
281 
282 	so->so_pcb = kp;
283 	so->so_options |= SO_USELOOPBACK;
284 
285 	KEYSOCK_LOCK();
286 	LIST_INSERT_HEAD(&V_keycb_list, kp, kp_next);
287 	KEYSOCK_UNLOCK();
288 	soisconnected(so);
289 
290 	return (0);
291 }
292 
293 static void
294 key_close(struct socket *so)
295 {
296 
297 	soisdisconnected(so);
298 }
299 
300 static void
301 key_detach(struct socket *so)
302 {
303 	struct keycb *kp = so->so_pcb;
304 
305 	key_freereg(so);
306 	KEYSOCK_LOCK();
307 	LIST_REMOVE(kp, kp_next);
308 	KEYSOCK_UNLOCK();
309 	free(kp, M_PCB);
310 	so->so_pcb = NULL;
311 }
312 
313 static int
314 key_shutdown(struct socket *so)
315 {
316 
317 	socantsendmore(so);
318 	return (0);
319 }
320 
321 SYSCTL_NODE(_net, PF_KEY, key, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
322     "Key Family");
323 
324 static struct protosw keysw = {
325 	.pr_type =		SOCK_RAW,
326 	.pr_protocol =		PF_KEY_V2,
327 	.pr_flags =		PR_ATOMIC|PR_ADDR,
328 	.pr_abort =		key_close,
329 	.pr_attach =		key_attach,
330 	.pr_detach =		key_detach,
331 	.pr_send =		key_send,
332 	.pr_shutdown =		key_shutdown,
333 	.pr_close =		key_close,
334 };
335 
336 static struct domain keydomain = {
337 	.dom_family =		PF_KEY,
338 	.dom_name =		"key",
339 	.dom_nprotosw =		1,
340 	.dom_protosw =		{ &keysw },
341 };
342 DOMAIN_SET(key);
343