xref: /freebsd/sys/kern/uipc_domain.c (revision 94942af266ac119ede0ca836f9aa5a5ac0582938)
1 /*-
2  * Copyright (c) 1982, 1986, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  *	@(#)uipc_domain.c	8.2 (Berkeley) 10/18/93
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include <sys/param.h>
36 #include <sys/socket.h>
37 #include <sys/protosw.h>
38 #include <sys/domain.h>
39 #include <sys/eventhandler.h>
40 #include <sys/mbuf.h>
41 #include <sys/kernel.h>
42 #include <sys/lock.h>
43 #include <sys/mutex.h>
44 #include <sys/socketvar.h>
45 #include <sys/systm.h>
46 #include <vm/uma.h>
47 
48 /*
49  * System initialization
50  *
51  * Note: domain initialization takes place on a per domain basis
52  * as a result of traversing a SYSINIT linker set.  Most likely,
53  * each domain would want to call DOMAIN_SET(9) itself, which
54  * would cause the domain to be added just after domaininit()
55  * is called during startup.
56  *
57  * See DOMAIN_SET(9) for details on its use.
58  */
59 
60 static void domaininit(void *);
61 SYSINIT(domain, SI_SUB_PROTO_DOMAIN, SI_ORDER_FIRST, domaininit, NULL)
62 
63 static void domainfinalize(void *);
64 SYSINIT(domainfin, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_FIRST, domainfinalize,
65     NULL)
66 
67 static struct callout pffast_callout;
68 static struct callout pfslow_callout;
69 
70 static void	pffasttimo(void *);
71 static void	pfslowtimo(void *);
72 
73 struct domain *domains;		/* registered protocol domains */
74 int domain_init_status = 0;
75 struct mtx dom_mtx;		/* domain list lock */
76 MTX_SYSINIT(domain, &dom_mtx, "domain list", MTX_DEF);
77 
78 /*
79  * Dummy protocol specific user requests function pointer array.
80  * All functions return EOPNOTSUPP.
81  */
82 struct pr_usrreqs nousrreqs = {
83 	.pru_accept =		pru_accept_notsupp,
84 	.pru_attach =		pru_attach_notsupp,
85 	.pru_bind =		pru_bind_notsupp,
86 	.pru_connect =		pru_connect_notsupp,
87 	.pru_connect2 =		pru_connect2_notsupp,
88 	.pru_control =		pru_control_notsupp,
89 	.pru_disconnect	=	pru_disconnect_notsupp,
90 	.pru_listen =		pru_listen_notsupp,
91 	.pru_peeraddr =		pru_peeraddr_notsupp,
92 	.pru_rcvd =		pru_rcvd_notsupp,
93 	.pru_rcvoob =		pru_rcvoob_notsupp,
94 	.pru_send =		pru_send_notsupp,
95 	.pru_sense =		pru_sense_null,
96 	.pru_shutdown =		pru_shutdown_notsupp,
97 	.pru_sockaddr =		pru_sockaddr_notsupp,
98 	.pru_sosend =		pru_sosend_notsupp,
99 	.pru_soreceive =	pru_soreceive_notsupp,
100 	.pru_sopoll =		pru_sopoll_notsupp,
101 };
102 
103 static void
104 protosw_init(struct protosw *pr)
105 {
106 	struct pr_usrreqs *pu;
107 
108 	pu = pr->pr_usrreqs;
109 	KASSERT(pu != NULL, ("protosw_init: %ssw[%d] has no usrreqs!",
110 	    pr->pr_domain->dom_name,
111 	    (int)(pr - pr->pr_domain->dom_protosw)));
112 
113 #define DEFAULT(foo, bar)	if ((foo) == NULL)  (foo) = (bar)
114 	DEFAULT(pu->pru_accept, pru_accept_notsupp);
115 	DEFAULT(pu->pru_connect, pru_connect_notsupp);
116 	DEFAULT(pu->pru_connect2, pru_connect2_notsupp);
117 	DEFAULT(pu->pru_control, pru_control_notsupp);
118 	DEFAULT(pu->pru_listen, pru_listen_notsupp);
119 	DEFAULT(pu->pru_rcvd, pru_rcvd_notsupp);
120 	DEFAULT(pu->pru_rcvoob, pru_rcvoob_notsupp);
121 	DEFAULT(pu->pru_sense, pru_sense_null);
122 	DEFAULT(pu->pru_sosend, sosend_generic);
123 	DEFAULT(pu->pru_soreceive, soreceive_generic);
124 	DEFAULT(pu->pru_sopoll, sopoll_generic);
125 #undef DEFAULT
126 	if (pr->pr_init)
127 		(*pr->pr_init)();
128 }
129 
130 /*
131  * Add a new protocol domain to the list of supported domains
132  * Note: you cant unload it again because a socket may be using it.
133  * XXX can't fail at this time.
134  */
135 static void
136 net_init_domain(struct domain *dp)
137 {
138 	struct protosw *pr;
139 
140 	if (dp->dom_init)
141 		(*dp->dom_init)();
142 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
143 		protosw_init(pr);
144 	/*
145 	 * update global information about maximums
146 	 */
147 	max_hdr = max_linkhdr + max_protohdr;
148 	max_datalen = MHLEN - max_hdr;
149 	if (max_datalen < 1)
150 		panic("%s: max_datalen < 1", __func__);
151 }
152 
153 /*
154  * Add a new protocol domain to the list of supported domains
155  * Note: you cant unload it again because a socket may be using it.
156  * XXX can't fail at this time.
157  */
158 void
159 net_add_domain(void *data)
160 {
161 	struct domain *dp;
162 
163 	dp = (struct domain *)data;
164 	mtx_lock(&dom_mtx);
165 	dp->dom_next = domains;
166 	domains = dp;
167 
168 	KASSERT(domain_init_status >= 1,
169 	    ("attempt to net_add_domain(%s) before domaininit()",
170 	    dp->dom_name));
171 #ifndef INVARIANTS
172 	if (domain_init_status < 1)
173 		printf("WARNING: attempt to net_add_domain(%s) before "
174 		    "domaininit()\n", dp->dom_name);
175 #endif
176 #ifdef notyet
177 	KASSERT(domain_init_status < 2,
178 	    ("attempt to net_add_domain(%s) after domainfinalize()",
179 	    dp->dom_name));
180 #else
181 	if (domain_init_status >= 2)
182 		printf("WARNING: attempt to net_add_domain(%s) after "
183 		    "domainfinalize()\n", dp->dom_name);
184 #endif
185 	mtx_unlock(&dom_mtx);
186 	net_init_domain(dp);
187 }
188 
189 static void
190 socket_zone_change(void *tag)
191 {
192 
193 	uma_zone_set_max(socket_zone, maxsockets);
194 }
195 
196 /* ARGSUSED*/
197 static void
198 domaininit(void *dummy)
199 {
200 
201 	/*
202 	 * Before we do any setup, make sure to initialize the
203 	 * zone allocator we get struct sockets from.
204 	 */
205 	socket_zone = uma_zcreate("socket", sizeof(struct socket), NULL, NULL,
206 	    NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_NOFREE);
207 	uma_zone_set_max(socket_zone, maxsockets);
208 	EVENTHANDLER_REGISTER(maxsockets_change, socket_zone_change, NULL,
209 		EVENTHANDLER_PRI_FIRST);
210 
211 	if (max_linkhdr < 16)		/* XXX */
212 		max_linkhdr = 16;
213 
214 	if (debug_mpsafenet) {
215 		callout_init(&pffast_callout, CALLOUT_MPSAFE);
216 		callout_init(&pfslow_callout, CALLOUT_MPSAFE);
217 	} else {
218 		callout_init(&pffast_callout, 0);
219 		callout_init(&pfslow_callout, 0);
220 	}
221 
222 	mtx_lock(&dom_mtx);
223 	KASSERT(domain_init_status == 0, ("domaininit called too late!"));
224 	domain_init_status = 1;
225 	mtx_unlock(&dom_mtx);
226 }
227 
228 /* ARGSUSED*/
229 static void
230 domainfinalize(void *dummy)
231 {
232 
233 	mtx_lock(&dom_mtx);
234 	KASSERT(domain_init_status == 1, ("domainfinalize called too late!"));
235 	domain_init_status = 2;
236 	mtx_unlock(&dom_mtx);
237 
238 	callout_reset(&pffast_callout, 1, pffasttimo, NULL);
239 	callout_reset(&pfslow_callout, 1, pfslowtimo, NULL);
240 }
241 
242 struct protosw *
243 pffindtype(int family, int type)
244 {
245 	struct domain *dp;
246 	struct protosw *pr;
247 
248 	for (dp = domains; dp; dp = dp->dom_next)
249 		if (dp->dom_family == family)
250 			goto found;
251 	return (0);
252 found:
253 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
254 		if (pr->pr_type && pr->pr_type == type)
255 			return (pr);
256 	return (0);
257 }
258 
259 struct protosw *
260 pffindproto(int family, int protocol, int type)
261 {
262 	struct domain *dp;
263 	struct protosw *pr;
264 	struct protosw *maybe = 0;
265 
266 	if (family == 0)
267 		return (0);
268 	for (dp = domains; dp; dp = dp->dom_next)
269 		if (dp->dom_family == family)
270 			goto found;
271 	return (0);
272 found:
273 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
274 		if ((pr->pr_protocol == protocol) && (pr->pr_type == type))
275 			return (pr);
276 
277 		if (type == SOCK_RAW && pr->pr_type == SOCK_RAW &&
278 		    pr->pr_protocol == 0 && maybe == (struct protosw *)0)
279 			maybe = pr;
280 	}
281 	return (maybe);
282 }
283 
284 /*
285  * The caller must make sure that the new protocol is fully set up and ready to
286  * accept requests before it is registered.
287  */
288 int
289 pf_proto_register(int family, struct protosw *npr)
290 {
291 	struct domain *dp;
292 	struct protosw *pr, *fpr;
293 
294 	/* Sanity checks. */
295 	if (family == 0)
296 		return (EPFNOSUPPORT);
297 	if (npr->pr_type == 0)
298 		return (EPROTOTYPE);
299 	if (npr->pr_protocol == 0)
300 		return (EPROTONOSUPPORT);
301 	if (npr->pr_usrreqs == NULL)
302 		return (ENXIO);
303 
304 	/* Try to find the specified domain based on the family. */
305 	for (dp = domains; dp; dp = dp->dom_next)
306 		if (dp->dom_family == family)
307 			goto found;
308 	return (EPFNOSUPPORT);
309 
310 found:
311 	/* Initialize backpointer to struct domain. */
312 	npr->pr_domain = dp;
313 	fpr = NULL;
314 
315 	/*
316 	 * Protect us against races when two protocol registrations for
317 	 * the same protocol happen at the same time.
318 	 */
319 	mtx_lock(&Giant);
320 
321 	/* The new protocol must not yet exist. */
322 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
323 		if ((pr->pr_type == npr->pr_type) &&
324 		    (pr->pr_protocol == npr->pr_protocol)) {
325 			mtx_unlock(&Giant);
326 			return (EEXIST);	/* XXX: Check only protocol? */
327 		}
328 		/* While here, remember the first free spacer. */
329 		if ((fpr == NULL) && (pr->pr_protocol == PROTO_SPACER))
330 			fpr = pr;
331 	}
332 
333 	/* If no free spacer is found we can't add the new protocol. */
334 	if (fpr == NULL) {
335 		mtx_unlock(&Giant);
336 		return (ENOMEM);
337 	}
338 
339 	/* Copy the new struct protosw over the spacer. */
340 	bcopy(npr, fpr, sizeof(*fpr));
341 
342 	/* Job is done, no more protection required. */
343 	mtx_unlock(&Giant);
344 
345 	/* Initialize and activate the protocol. */
346 	protosw_init(fpr);
347 
348 	return (0);
349 }
350 
351 /*
352  * The caller must make sure the protocol and its functions correctly shut down
353  * all sockets and release all locks and memory references.
354  */
355 int
356 pf_proto_unregister(int family, int protocol, int type)
357 {
358 	struct domain *dp;
359 	struct protosw *pr, *dpr;
360 
361 	/* Sanity checks. */
362 	if (family == 0)
363 		return (EPFNOSUPPORT);
364 	if (protocol == 0)
365 		return (EPROTONOSUPPORT);
366 	if (type == 0)
367 		return (EPROTOTYPE);
368 
369 	/* Try to find the specified domain based on the family type. */
370 	for (dp = domains; dp; dp = dp->dom_next)
371 		if (dp->dom_family == family)
372 			goto found;
373 	return (EPFNOSUPPORT);
374 
375 found:
376 	dpr = NULL;
377 
378 	/* Lock out everyone else while we are manipulating the protosw. */
379 	mtx_lock(&Giant);
380 
381 	/* The protocol must exist and only once. */
382 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
383 		if ((pr->pr_type == type) && (pr->pr_protocol == protocol)) {
384 			if (dpr != NULL) {
385 				mtx_unlock(&Giant);
386 				return (EMLINK);   /* Should not happen! */
387 			} else
388 				dpr = pr;
389 		}
390 	}
391 
392 	/* Protocol does not exist. */
393 	if (dpr == NULL) {
394 		mtx_unlock(&Giant);
395 		return (EPROTONOSUPPORT);
396 	}
397 
398 	/* De-orbit the protocol and make the slot available again. */
399 	dpr->pr_type = 0;
400 	dpr->pr_domain = dp;
401 	dpr->pr_protocol = PROTO_SPACER;
402 	dpr->pr_flags = 0;
403 	dpr->pr_input = NULL;
404 	dpr->pr_output = NULL;
405 	dpr->pr_ctlinput = NULL;
406 	dpr->pr_ctloutput = NULL;
407 	dpr->pr_ousrreq = NULL;
408 	dpr->pr_init = NULL;
409 	dpr->pr_fasttimo = NULL;
410 	dpr->pr_slowtimo = NULL;
411 	dpr->pr_drain = NULL;
412 	dpr->pr_usrreqs = &nousrreqs;
413 
414 	/* Job is done, not more protection required. */
415 	mtx_unlock(&Giant);
416 
417 	return (0);
418 }
419 
420 void
421 pfctlinput(int cmd, struct sockaddr *sa)
422 {
423 	struct domain *dp;
424 	struct protosw *pr;
425 
426 	for (dp = domains; dp; dp = dp->dom_next)
427 		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
428 			if (pr->pr_ctlinput)
429 				(*pr->pr_ctlinput)(cmd, sa, (void *)0);
430 }
431 
432 void
433 pfctlinput2(int cmd, struct sockaddr *sa, void *ctlparam)
434 {
435 	struct domain *dp;
436 	struct protosw *pr;
437 
438 	if (!sa)
439 		return;
440 	for (dp = domains; dp; dp = dp->dom_next) {
441 		/*
442 		 * the check must be made by xx_ctlinput() anyways, to
443 		 * make sure we use data item pointed to by ctlparam in
444 		 * correct way.  the following check is made just for safety.
445 		 */
446 		if (dp->dom_family != sa->sa_family)
447 			continue;
448 
449 		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
450 			if (pr->pr_ctlinput)
451 				(*pr->pr_ctlinput)(cmd, sa, ctlparam);
452 	}
453 }
454 
455 static void
456 pfslowtimo(void *arg)
457 {
458 	struct domain *dp;
459 	struct protosw *pr;
460 
461 	NET_ASSERT_GIANT();
462 
463 	for (dp = domains; dp; dp = dp->dom_next)
464 		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
465 			if (pr->pr_slowtimo)
466 				(*pr->pr_slowtimo)();
467 	callout_reset(&pfslow_callout, hz/2, pfslowtimo, NULL);
468 }
469 
470 static void
471 pffasttimo(void *arg)
472 {
473 	struct domain *dp;
474 	struct protosw *pr;
475 
476 	NET_ASSERT_GIANT();
477 
478 	for (dp = domains; dp; dp = dp->dom_next)
479 		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
480 			if (pr->pr_fasttimo)
481 				(*pr->pr_fasttimo)();
482 	callout_reset(&pffast_callout, hz/5, pffasttimo, NULL);
483 }
484