xref: /freebsd/sys/kern/uipc_domain.c (revision 35a04710d7286aa9538917fd7f8e417dbee95b82)
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 	callout_init(&pffast_callout, CALLOUT_MPSAFE);
215 	callout_init(&pfslow_callout, CALLOUT_MPSAFE);
216 
217 	mtx_lock(&dom_mtx);
218 	KASSERT(domain_init_status == 0, ("domaininit called too late!"));
219 	domain_init_status = 1;
220 	mtx_unlock(&dom_mtx);
221 }
222 
223 /* ARGSUSED*/
224 static void
225 domainfinalize(void *dummy)
226 {
227 
228 	mtx_lock(&dom_mtx);
229 	KASSERT(domain_init_status == 1, ("domainfinalize called too late!"));
230 	domain_init_status = 2;
231 	mtx_unlock(&dom_mtx);
232 
233 	callout_reset(&pffast_callout, 1, pffasttimo, NULL);
234 	callout_reset(&pfslow_callout, 1, pfslowtimo, NULL);
235 }
236 
237 struct protosw *
238 pffindtype(int family, int type)
239 {
240 	struct domain *dp;
241 	struct protosw *pr;
242 
243 	for (dp = domains; dp; dp = dp->dom_next)
244 		if (dp->dom_family == family)
245 			goto found;
246 	return (0);
247 found:
248 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
249 		if (pr->pr_type && pr->pr_type == type)
250 			return (pr);
251 	return (0);
252 }
253 
254 struct protosw *
255 pffindproto(int family, int protocol, int type)
256 {
257 	struct domain *dp;
258 	struct protosw *pr;
259 	struct protosw *maybe = 0;
260 
261 	if (family == 0)
262 		return (0);
263 	for (dp = domains; dp; dp = dp->dom_next)
264 		if (dp->dom_family == family)
265 			goto found;
266 	return (0);
267 found:
268 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
269 		if ((pr->pr_protocol == protocol) && (pr->pr_type == type))
270 			return (pr);
271 
272 		if (type == SOCK_RAW && pr->pr_type == SOCK_RAW &&
273 		    pr->pr_protocol == 0 && maybe == (struct protosw *)0)
274 			maybe = pr;
275 	}
276 	return (maybe);
277 }
278 
279 /*
280  * The caller must make sure that the new protocol is fully set up and ready to
281  * accept requests before it is registered.
282  */
283 int
284 pf_proto_register(int family, struct protosw *npr)
285 {
286 	struct domain *dp;
287 	struct protosw *pr, *fpr;
288 
289 	/* Sanity checks. */
290 	if (family == 0)
291 		return (EPFNOSUPPORT);
292 	if (npr->pr_type == 0)
293 		return (EPROTOTYPE);
294 	if (npr->pr_protocol == 0)
295 		return (EPROTONOSUPPORT);
296 	if (npr->pr_usrreqs == NULL)
297 		return (ENXIO);
298 
299 	/* Try to find the specified domain based on the family. */
300 	for (dp = domains; dp; dp = dp->dom_next)
301 		if (dp->dom_family == family)
302 			goto found;
303 	return (EPFNOSUPPORT);
304 
305 found:
306 	/* Initialize backpointer to struct domain. */
307 	npr->pr_domain = dp;
308 	fpr = NULL;
309 
310 	/*
311 	 * Protect us against races when two protocol registrations for
312 	 * the same protocol happen at the same time.
313 	 */
314 	mtx_lock(&Giant);
315 
316 	/* The new protocol must not yet exist. */
317 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
318 		if ((pr->pr_type == npr->pr_type) &&
319 		    (pr->pr_protocol == npr->pr_protocol)) {
320 			mtx_unlock(&Giant);
321 			return (EEXIST);	/* XXX: Check only protocol? */
322 		}
323 		/* While here, remember the first free spacer. */
324 		if ((fpr == NULL) && (pr->pr_protocol == PROTO_SPACER))
325 			fpr = pr;
326 	}
327 
328 	/* If no free spacer is found we can't add the new protocol. */
329 	if (fpr == NULL) {
330 		mtx_unlock(&Giant);
331 		return (ENOMEM);
332 	}
333 
334 	/* Copy the new struct protosw over the spacer. */
335 	bcopy(npr, fpr, sizeof(*fpr));
336 
337 	/* Job is done, no more protection required. */
338 	mtx_unlock(&Giant);
339 
340 	/* Initialize and activate the protocol. */
341 	protosw_init(fpr);
342 
343 	return (0);
344 }
345 
346 /*
347  * The caller must make sure the protocol and its functions correctly shut down
348  * all sockets and release all locks and memory references.
349  */
350 int
351 pf_proto_unregister(int family, int protocol, int type)
352 {
353 	struct domain *dp;
354 	struct protosw *pr, *dpr;
355 
356 	/* Sanity checks. */
357 	if (family == 0)
358 		return (EPFNOSUPPORT);
359 	if (protocol == 0)
360 		return (EPROTONOSUPPORT);
361 	if (type == 0)
362 		return (EPROTOTYPE);
363 
364 	/* Try to find the specified domain based on the family type. */
365 	for (dp = domains; dp; dp = dp->dom_next)
366 		if (dp->dom_family == family)
367 			goto found;
368 	return (EPFNOSUPPORT);
369 
370 found:
371 	dpr = NULL;
372 
373 	/* Lock out everyone else while we are manipulating the protosw. */
374 	mtx_lock(&Giant);
375 
376 	/* The protocol must exist and only once. */
377 	for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
378 		if ((pr->pr_type == type) && (pr->pr_protocol == protocol)) {
379 			if (dpr != NULL) {
380 				mtx_unlock(&Giant);
381 				return (EMLINK);   /* Should not happen! */
382 			} else
383 				dpr = pr;
384 		}
385 	}
386 
387 	/* Protocol does not exist. */
388 	if (dpr == NULL) {
389 		mtx_unlock(&Giant);
390 		return (EPROTONOSUPPORT);
391 	}
392 
393 	/* De-orbit the protocol and make the slot available again. */
394 	dpr->pr_type = 0;
395 	dpr->pr_domain = dp;
396 	dpr->pr_protocol = PROTO_SPACER;
397 	dpr->pr_flags = 0;
398 	dpr->pr_input = NULL;
399 	dpr->pr_output = NULL;
400 	dpr->pr_ctlinput = NULL;
401 	dpr->pr_ctloutput = NULL;
402 	dpr->pr_ousrreq = NULL;
403 	dpr->pr_init = NULL;
404 	dpr->pr_fasttimo = NULL;
405 	dpr->pr_slowtimo = NULL;
406 	dpr->pr_drain = NULL;
407 	dpr->pr_usrreqs = &nousrreqs;
408 
409 	/* Job is done, not more protection required. */
410 	mtx_unlock(&Giant);
411 
412 	return (0);
413 }
414 
415 void
416 pfctlinput(int cmd, struct sockaddr *sa)
417 {
418 	struct domain *dp;
419 	struct protosw *pr;
420 
421 	for (dp = domains; dp; dp = dp->dom_next)
422 		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
423 			if (pr->pr_ctlinput)
424 				(*pr->pr_ctlinput)(cmd, sa, (void *)0);
425 }
426 
427 void
428 pfctlinput2(int cmd, struct sockaddr *sa, void *ctlparam)
429 {
430 	struct domain *dp;
431 	struct protosw *pr;
432 
433 	if (!sa)
434 		return;
435 	for (dp = domains; dp; dp = dp->dom_next) {
436 		/*
437 		 * the check must be made by xx_ctlinput() anyways, to
438 		 * make sure we use data item pointed to by ctlparam in
439 		 * correct way.  the following check is made just for safety.
440 		 */
441 		if (dp->dom_family != sa->sa_family)
442 			continue;
443 
444 		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
445 			if (pr->pr_ctlinput)
446 				(*pr->pr_ctlinput)(cmd, sa, ctlparam);
447 	}
448 }
449 
450 static void
451 pfslowtimo(void *arg)
452 {
453 	struct domain *dp;
454 	struct protosw *pr;
455 
456 	for (dp = domains; dp; dp = dp->dom_next)
457 		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
458 			if (pr->pr_slowtimo)
459 				(*pr->pr_slowtimo)();
460 	callout_reset(&pfslow_callout, hz/2, pfslowtimo, NULL);
461 }
462 
463 static void
464 pffasttimo(void *arg)
465 {
466 	struct domain *dp;
467 	struct protosw *pr;
468 
469 	for (dp = domains; dp; dp = dp->dom_next)
470 		for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
471 			if (pr->pr_fasttimo)
472 				(*pr->pr_fasttimo)();
473 	callout_reset(&pffast_callout, hz/5, pffasttimo, NULL);
474 }
475