xref: /freebsd/sys/kern/uipc_domain.c (revision e91d723ad446b5429318b24f4578a4f7a160f65e)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1982, 1986, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	@(#)uipc_domain.c	8.2 (Berkeley) 10/18/93
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include <sys/param.h>
38 #include <sys/socket.h>
39 #include <sys/protosw.h>
40 #include <sys/domain.h>
41 #include <sys/eventhandler.h>
42 #include <sys/mbuf.h>
43 #include <sys/kernel.h>
44 #include <sys/lock.h>
45 #include <sys/mutex.h>
46 #include <sys/socketvar.h>
47 #include <sys/systm.h>
48 
49 #include <net/vnet.h>
50 
51 /*
52  * System initialization
53  *
54  * Note: domain initialization takes place on a per domain basis
55  * as a result of traversing a SYSINIT linker set.  Most likely,
56  * each domain would want to call DOMAIN_SET(9) itself, which
57  * would cause the domain to be added just after domaininit()
58  * is called during startup.
59  *
60  * See DOMAIN_SET(9) for details on its use.
61  */
62 
63 static void domaininit(void *);
64 SYSINIT(domain, SI_SUB_PROTO_DOMAININIT, SI_ORDER_ANY, domaininit, NULL);
65 
66 static void domainfinalize(void *);
67 SYSINIT(domainfin, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_FIRST, domainfinalize,
68     NULL);
69 
70 static struct callout pffast_callout;
71 static struct callout pfslow_callout;
72 
73 static void	pffasttimo(void *);
74 static void	pfslowtimo(void *);
75 
76 struct domain *domains;		/* registered protocol domains */
77 int domain_init_status = 0;
78 static struct mtx dom_mtx;		/* domain list lock */
79 MTX_SYSINIT(domain, &dom_mtx, "domain list", MTX_DEF);
80 
81 /*
82  * Dummy protocol specific user requests function pointer array.
83  * All functions return EOPNOTSUPP.
84  */
85 struct pr_usrreqs nousrreqs = {
86 	.pru_accept =		pru_accept_notsupp,
87 	.pru_attach =		pru_attach_notsupp,
88 	.pru_bind =		pru_bind_notsupp,
89 	.pru_connect =		pru_connect_notsupp,
90 	.pru_connect2 =		pru_connect2_notsupp,
91 	.pru_control =		pru_control_notsupp,
92 	.pru_disconnect	=	pru_disconnect_notsupp,
93 	.pru_listen =		pru_listen_notsupp,
94 	.pru_peeraddr =		pru_peeraddr_notsupp,
95 	.pru_rcvd =		pru_rcvd_notsupp,
96 	.pru_rcvoob =		pru_rcvoob_notsupp,
97 	.pru_send =		pru_send_notsupp,
98 	.pru_sense =		pru_sense_null,
99 	.pru_shutdown =		pru_shutdown_notsupp,
100 	.pru_sockaddr =		pru_sockaddr_notsupp,
101 	.pru_sosend =		pru_sosend_notsupp,
102 	.pru_soreceive =	pru_soreceive_notsupp,
103 	.pru_sopoll =		pru_sopoll_notsupp,
104 };
105 
106 static void
107 protosw_init(struct protosw *pr)
108 {
109 	struct pr_usrreqs *pu;
110 
111 	pu = pr->pr_usrreqs;
112 	KASSERT(pu != NULL, ("protosw_init: %ssw[%d] has no usrreqs!",
113 	    pr->pr_domain->dom_name,
114 	    (int)(pr - pr->pr_domain->dom_protosw)));
115 
116 	/*
117 	 * Protocol switch methods fall into three categories: mandatory,
118 	 * mandatory but protosw_init() provides a default, and optional.
119 	 *
120 	 * For true protocols (i.e., pru_attach != NULL), KASSERT truly
121 	 * mandatory methods with no defaults, and initialize defaults for
122 	 * other mandatory methods if the protocol hasn't defined an
123 	 * implementation (NULL function pointer).
124 	 */
125 #if 0
126 	if (pu->pru_attach != NULL) {
127 		KASSERT(pu->pru_abort != NULL,
128 		    ("protosw_init: %ssw[%d] pru_abort NULL",
129 		    pr->pr_domain->dom_name,
130 		    (int)(pr - pr->pr_domain->dom_protosw)));
131 		KASSERT(pu->pru_send != NULL,
132 		    ("protosw_init: %ssw[%d] pru_send NULL",
133 		    pr->pr_domain->dom_name,
134 		    (int)(pr - pr->pr_domain->dom_protosw)));
135 	}
136 #endif
137 
138 #define DEFAULT(foo, bar)	if ((foo) == NULL)  (foo) = (bar)
139 	DEFAULT(pu->pru_accept, pru_accept_notsupp);
140 	DEFAULT(pu->pru_aio_queue, pru_aio_queue_notsupp);
141 	DEFAULT(pu->pru_bind, pru_bind_notsupp);
142 	DEFAULT(pu->pru_bindat, pru_bindat_notsupp);
143 	DEFAULT(pu->pru_connect, pru_connect_notsupp);
144 	DEFAULT(pu->pru_connect2, pru_connect2_notsupp);
145 	DEFAULT(pu->pru_connectat, pru_connectat_notsupp);
146 	DEFAULT(pu->pru_control, pru_control_notsupp);
147 	DEFAULT(pu->pru_disconnect, pru_disconnect_notsupp);
148 	DEFAULT(pu->pru_listen, pru_listen_notsupp);
149 	DEFAULT(pu->pru_peeraddr, pru_peeraddr_notsupp);
150 	DEFAULT(pu->pru_rcvd, pru_rcvd_notsupp);
151 	DEFAULT(pu->pru_rcvoob, pru_rcvoob_notsupp);
152 	DEFAULT(pu->pru_sense, pru_sense_null);
153 	DEFAULT(pu->pru_shutdown, pru_shutdown_notsupp);
154 	DEFAULT(pu->pru_sockaddr, pru_sockaddr_notsupp);
155 	DEFAULT(pu->pru_sosend, sosend_generic);
156 	DEFAULT(pu->pru_soreceive, soreceive_generic);
157 	DEFAULT(pu->pru_sopoll, sopoll_generic);
158 	DEFAULT(pu->pru_ready, pru_ready_notsupp);
159 #undef DEFAULT
160 	if (pr->pr_init)
161 		(*pr->pr_init)();
162 }
163 
164 /*
165  * Add a new protocol domain to the list of supported domains
166  * Note: you cant unload it again because a socket may be using it.
167  * XXX can't fail at this time.
168  */
169 void
170 domain_init(void *arg)
171 {
172 	struct domain *dp = arg;
173 	struct protosw *pr;
174 
175 	if (dp->dom_init)
176 		(*dp->dom_init)();
177 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
178 		protosw_init(pr);
179 	/*
180 	 * update global information about maximums
181 	 */
182 	max_hdr = max_linkhdr + max_protohdr;
183 	max_datalen = MHLEN - max_hdr;
184 	if (max_datalen < 1)
185 		panic("%s: max_datalen < 1", __func__);
186 }
187 
188 #ifdef VIMAGE
189 void
190 vnet_domain_init(void *arg)
191 {
192 
193 	/* Virtualized case is no different -- call init functions. */
194 	domain_init(arg);
195 }
196 
197 void
198 vnet_domain_uninit(void *arg)
199 {
200 	struct domain *dp = arg;
201 
202 	if (dp->dom_destroy)
203 		(*dp->dom_destroy)();
204 }
205 #endif
206 
207 /*
208  * Add a new protocol domain to the list of supported domains
209  * Note: you cant unload it again because a socket may be using it.
210  * XXX can't fail at this time.
211  */
212 void
213 domain_add(void *data)
214 {
215 	struct domain *dp;
216 
217 	dp = (struct domain *)data;
218 	mtx_lock(&dom_mtx);
219 	dp->dom_next = domains;
220 	domains = dp;
221 
222 	KASSERT(domain_init_status >= 1,
223 	    ("attempt to domain_add(%s) before domaininit()",
224 	    dp->dom_name));
225 #ifndef INVARIANTS
226 	if (domain_init_status < 1)
227 		printf("WARNING: attempt to domain_add(%s) before "
228 		    "domaininit()\n", dp->dom_name);
229 #endif
230 #ifdef notyet
231 	KASSERT(domain_init_status < 2,
232 	    ("attempt to domain_add(%s) after domainfinalize()",
233 	    dp->dom_name));
234 #else
235 	if (domain_init_status >= 2)
236 		printf("WARNING: attempt to domain_add(%s) after "
237 		    "domainfinalize()\n", dp->dom_name);
238 #endif
239 	mtx_unlock(&dom_mtx);
240 }
241 
242 /* ARGSUSED*/
243 static void
244 domaininit(void *dummy)
245 {
246 
247 	if (max_linkhdr < 16)		/* XXX */
248 		max_linkhdr = 16;
249 
250 	callout_init(&pffast_callout, 1);
251 	callout_init(&pfslow_callout, 1);
252 
253 	mtx_lock(&dom_mtx);
254 	KASSERT(domain_init_status == 0, ("domaininit called too late!"));
255 	domain_init_status = 1;
256 	mtx_unlock(&dom_mtx);
257 }
258 
259 /* ARGSUSED*/
260 static void
261 domainfinalize(void *dummy)
262 {
263 
264 	mtx_lock(&dom_mtx);
265 	KASSERT(domain_init_status == 1, ("domainfinalize called too late!"));
266 	domain_init_status = 2;
267 	mtx_unlock(&dom_mtx);
268 
269 	callout_reset(&pffast_callout, 1, pffasttimo, NULL);
270 	callout_reset(&pfslow_callout, 1, pfslowtimo, NULL);
271 }
272 
273 struct domain *
274 pffinddomain(int family)
275 {
276 	struct domain *dp;
277 
278 	for (dp = domains; dp != NULL; dp = dp->dom_next)
279 		if (dp->dom_family == family)
280 			return (dp);
281 	return (NULL);
282 }
283 
284 struct protosw *
285 pffindtype(int family, int type)
286 {
287 	struct domain *dp;
288 	struct protosw *pr;
289 
290 	dp = pffinddomain(family);
291 	if (dp == NULL)
292 		return (NULL);
293 
294 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
295 		if (pr->pr_type && pr->pr_type == type)
296 			return (pr);
297 	return (NULL);
298 }
299 
300 struct protosw *
301 pffindproto(int family, int protocol, int type)
302 {
303 	struct domain *dp;
304 	struct protosw *pr;
305 	struct protosw *maybe;
306 
307 	maybe = NULL;
308 	if (family == 0)
309 		return (NULL);
310 
311 	dp = pffinddomain(family);
312 	if (dp == NULL)
313 		return (NULL);
314 
315 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
316 		if ((pr->pr_protocol == protocol) && (pr->pr_type == type))
317 			return (pr);
318 
319 		if (type == SOCK_RAW && pr->pr_type == SOCK_RAW &&
320 		    pr->pr_protocol == 0 && maybe == NULL)
321 			maybe = pr;
322 	}
323 	return (maybe);
324 }
325 
326 /*
327  * The caller must make sure that the new protocol is fully set up and ready to
328  * accept requests before it is registered.
329  */
330 int
331 pf_proto_register(int family, struct protosw *npr)
332 {
333 	VNET_ITERATOR_DECL(vnet_iter);
334 	struct domain *dp;
335 	struct protosw *pr, *fpr;
336 
337 	/* Sanity checks. */
338 	if (family == 0)
339 		return (EPFNOSUPPORT);
340 	if (npr->pr_type == 0)
341 		return (EPROTOTYPE);
342 	if (npr->pr_protocol == 0)
343 		return (EPROTONOSUPPORT);
344 	if (npr->pr_usrreqs == NULL)
345 		return (ENXIO);
346 
347 	/* Try to find the specified domain based on the family. */
348 	dp = pffinddomain(family);
349 	if (dp == NULL)
350 		return (EPFNOSUPPORT);
351 
352 	/* Initialize backpointer to struct domain. */
353 	npr->pr_domain = dp;
354 	fpr = NULL;
355 
356 	/*
357 	 * Protect us against races when two protocol registrations for
358 	 * the same protocol happen at the same time.
359 	 */
360 	mtx_lock(&dom_mtx);
361 
362 	/* The new protocol must not yet exist. */
363 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
364 		if ((pr->pr_type == npr->pr_type) &&
365 		    (pr->pr_protocol == npr->pr_protocol)) {
366 			mtx_unlock(&dom_mtx);
367 			return (EEXIST);	/* XXX: Check only protocol? */
368 		}
369 		/* While here, remember the first free spacer. */
370 		if ((fpr == NULL) && (pr->pr_protocol == PROTO_SPACER))
371 			fpr = pr;
372 	}
373 
374 	/* If no free spacer is found we can't add the new protocol. */
375 	if (fpr == NULL) {
376 		mtx_unlock(&dom_mtx);
377 		return (ENOMEM);
378 	}
379 
380 	/* Copy the new struct protosw over the spacer. */
381 	bcopy(npr, fpr, sizeof(*fpr));
382 
383 	/* Job is done, no more protection required. */
384 	mtx_unlock(&dom_mtx);
385 
386 	/* Initialize and activate the protocol. */
387 	VNET_LIST_RLOCK();
388 	VNET_FOREACH(vnet_iter) {
389 		CURVNET_SET_QUIET(vnet_iter);
390 		protosw_init(fpr);
391 		CURVNET_RESTORE();
392 	}
393 	VNET_LIST_RUNLOCK();
394 
395 	return (0);
396 }
397 
398 /*
399  * The caller must make sure the protocol and its functions correctly shut down
400  * all sockets and release all locks and memory references.
401  */
402 int
403 pf_proto_unregister(int family, int protocol, int type)
404 {
405 	struct domain *dp;
406 	struct protosw *pr, *dpr;
407 
408 	/* Sanity checks. */
409 	if (family == 0)
410 		return (EPFNOSUPPORT);
411 	if (protocol == 0)
412 		return (EPROTONOSUPPORT);
413 	if (type == 0)
414 		return (EPROTOTYPE);
415 
416 	/* Try to find the specified domain based on the family type. */
417 	dp = pffinddomain(family);
418 	if (dp == NULL)
419 		return (EPFNOSUPPORT);
420 
421 	dpr = NULL;
422 
423 	/* Lock out everyone else while we are manipulating the protosw. */
424 	mtx_lock(&dom_mtx);
425 
426 	/* The protocol must exist and only once. */
427 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
428 		if ((pr->pr_type == type) && (pr->pr_protocol == protocol)) {
429 			if (dpr != NULL) {
430 				mtx_unlock(&dom_mtx);
431 				return (EMLINK);   /* Should not happen! */
432 			} else
433 				dpr = pr;
434 		}
435 	}
436 
437 	/* Protocol does not exist. */
438 	if (dpr == NULL) {
439 		mtx_unlock(&dom_mtx);
440 		return (EPROTONOSUPPORT);
441 	}
442 
443 	/* De-orbit the protocol and make the slot available again. */
444 	dpr->pr_type = 0;
445 	dpr->pr_domain = dp;
446 	dpr->pr_protocol = PROTO_SPACER;
447 	dpr->pr_flags = 0;
448 	dpr->pr_input = NULL;
449 	dpr->pr_output = NULL;
450 	dpr->pr_ctlinput = NULL;
451 	dpr->pr_ctloutput = NULL;
452 	dpr->pr_init = NULL;
453 	dpr->pr_fasttimo = NULL;
454 	dpr->pr_slowtimo = NULL;
455 	dpr->pr_drain = NULL;
456 	dpr->pr_usrreqs = &nousrreqs;
457 
458 	/* Job is done, not more protection required. */
459 	mtx_unlock(&dom_mtx);
460 
461 	return (0);
462 }
463 
464 void
465 pfctlinput(int cmd, struct sockaddr *sa)
466 {
467 	struct domain *dp;
468 	struct protosw *pr;
469 
470 	for (dp = domains; dp; dp = dp->dom_next)
471 		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
472 			if (pr->pr_ctlinput)
473 				(*pr->pr_ctlinput)(cmd, sa, (void *)0);
474 }
475 
476 void
477 pfctlinput2(int cmd, struct sockaddr *sa, void *ctlparam)
478 {
479 	struct domain *dp;
480 	struct protosw *pr;
481 
482 	if (!sa)
483 		return;
484 	for (dp = domains; dp; dp = dp->dom_next) {
485 		/*
486 		 * the check must be made by xx_ctlinput() anyways, to
487 		 * make sure we use data item pointed to by ctlparam in
488 		 * correct way.  the following check is made just for safety.
489 		 */
490 		if (dp->dom_family != sa->sa_family)
491 			continue;
492 
493 		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
494 			if (pr->pr_ctlinput)
495 				(*pr->pr_ctlinput)(cmd, sa, ctlparam);
496 	}
497 }
498 
499 static void
500 pfslowtimo(void *arg)
501 {
502 	struct domain *dp;
503 	struct protosw *pr;
504 
505 	for (dp = domains; dp; dp = dp->dom_next)
506 		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
507 			if (pr->pr_slowtimo)
508 				(*pr->pr_slowtimo)();
509 	callout_reset(&pfslow_callout, hz/2, pfslowtimo, NULL);
510 }
511 
512 static void
513 pffasttimo(void *arg)
514 {
515 	struct domain *dp;
516 	struct protosw *pr;
517 
518 	for (dp = domains; dp; dp = dp->dom_next)
519 		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
520 			if (pr->pr_fasttimo)
521 				(*pr->pr_fasttimo)();
522 	callout_reset(&pffast_callout, hz/5, pffasttimo, NULL);
523 }
524