xref: /netbsd-src/sys/net/link_proto.c (revision 6cf6fe02a981b55727c49c3d37b0d8191a98c0ee)
1 /*	$NetBSD: link_proto.c,v 1.24 2014/08/09 05:33:01 rtr Exp $	*/
2 
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_proto.c	8.2 (Berkeley) 2/14/95
32  */
33 
34 #include <sys/cdefs.h>
35 __KERNEL_RCSID(0, "$NetBSD: link_proto.c,v 1.24 2014/08/09 05:33:01 rtr Exp $");
36 
37 #include <sys/param.h>
38 #include <sys/socket.h>
39 #include <sys/protosw.h>
40 #include <sys/domain.h>
41 #include <sys/mbuf.h>
42 #include <sys/un.h>
43 #include <sys/socketvar.h>
44 
45 #include <net/if.h>
46 #include <net/if_dl.h>
47 #include <net/raw_cb.h>
48 #include <net/route.h>
49 
50 static int sockaddr_dl_cmp(const struct sockaddr *, const struct sockaddr *);
51 static int link_attach(struct socket *, int);
52 static void link_detach(struct socket *);
53 static int link_accept(struct socket *, struct mbuf *);
54 static int link_bind(struct socket *, struct mbuf *, struct lwp *);
55 static int link_listen(struct socket *, struct lwp *);
56 static int link_connect(struct socket *, struct mbuf *, struct lwp *);
57 static int link_connect2(struct socket *, struct socket *);
58 static int link_disconnect(struct socket *);
59 static int link_shutdown(struct socket *);
60 static int link_abort(struct socket *);
61 static int link_ioctl(struct socket *, u_long, void *, struct ifnet *);
62 static int link_stat(struct socket *, struct stat *);
63 static int link_peeraddr(struct socket *, struct mbuf *);
64 static int link_sockaddr(struct socket *, struct mbuf *);
65 static int link_rcvd(struct socket *, int, struct lwp *);
66 static int link_recvoob(struct socket *, struct mbuf *, int);
67 static int link_send(struct socket *, struct mbuf *, struct mbuf *,
68     struct mbuf *, struct lwp *);
69 static int link_sendoob(struct socket *, struct mbuf *, struct mbuf *);
70 static int link_purgeif(struct socket *, struct ifnet *);
71 static int link_usrreq(struct socket *, int, struct mbuf *, struct mbuf *,
72     struct mbuf *, struct lwp *);
73 static void link_init(void);
74 
75 /*
76  * Definitions of protocols supported in the link-layer domain.
77  */
78 
79 DOMAIN_DEFINE(linkdomain);	/* forward define and add to link set */
80 
81 static const struct pr_usrreqs link_usrreqs = {
82 	.pr_attach	= link_attach,
83 	.pr_detach	= link_detach,
84 	.pr_accept	= link_accept,
85 	.pr_bind	= link_bind,
86 	.pr_listen	= link_listen,
87 	.pr_connect	= link_connect,
88 	.pr_connect2	= link_connect2,
89 	.pr_disconnect	= link_disconnect,
90 	.pr_shutdown	= link_shutdown,
91 	.pr_abort	= link_abort,
92 	.pr_ioctl	= link_ioctl,
93 	.pr_stat	= link_stat,
94 	.pr_peeraddr	= link_peeraddr,
95 	.pr_sockaddr	= link_sockaddr,
96 	.pr_rcvd	= link_rcvd,
97 	.pr_recvoob	= link_recvoob,
98 	.pr_send	= link_send,
99 	.pr_sendoob	= link_sendoob,
100 	.pr_purgeif	= link_purgeif,
101 	.pr_generic	= link_usrreq,
102 };
103 
104 const struct protosw linksw[] = {
105 	{	.pr_type = SOCK_DGRAM,
106 		.pr_domain = &linkdomain,
107 		.pr_protocol = 0,	/* XXX */
108 		.pr_flags = PR_ATOMIC|PR_ADDR|PR_PURGEIF,
109 		.pr_input = NULL,
110 		.pr_ctlinput = NULL,
111 		.pr_ctloutput = NULL,
112 		.pr_usrreqs = &link_usrreqs,
113 		.pr_init = link_init,
114 	},
115 };
116 
117 struct domain linkdomain = {
118 	.dom_family = AF_LINK,
119 	.dom_name = "link",
120 	.dom_externalize = NULL,
121 	.dom_dispose = NULL,
122 	.dom_protosw = linksw,
123 	.dom_protoswNPROTOSW = &linksw[__arraycount(linksw)],
124 	.dom_sockaddr_cmp = sockaddr_dl_cmp
125 };
126 
127 static void
128 link_init(void)
129 {
130 	return;
131 }
132 
133 static int
134 link_control(struct socket *so, unsigned long cmd, void *data,
135     struct ifnet *ifp)
136 {
137 	int error, s;
138 	bool isactive, mkactive;
139 	struct if_laddrreq *iflr;
140 	union {
141 		struct sockaddr sa;
142 		struct sockaddr_dl sdl;
143 		struct sockaddr_storage ss;
144 	} u;
145 	struct ifaddr *ifa;
146 	const struct sockaddr_dl *asdl, *nsdl;
147 
148 	switch (cmd) {
149 	case SIOCALIFADDR:
150 	case SIOCDLIFADDR:
151 	case SIOCGLIFADDR:
152 		iflr = data;
153 
154 		if (iflr->addr.ss_family != AF_LINK)
155 			return EINVAL;
156 
157 		asdl = satocsdl(sstocsa(&iflr->addr));
158 
159 		if (asdl->sdl_alen != ifp->if_addrlen)
160 			return EINVAL;
161 
162 		if (sockaddr_dl_init(&u.sdl, sizeof(u.ss), ifp->if_index,
163 		    ifp->if_type, ifp->if_xname, strlen(ifp->if_xname),
164 		    CLLADDR(asdl), asdl->sdl_alen) == NULL)
165 			return EINVAL;
166 
167 		if ((iflr->flags & IFLR_PREFIX) == 0)
168 			;
169 		else if (iflr->prefixlen != NBBY * ifp->if_addrlen)
170 			return EINVAL;	/* XXX match with prefix */
171 
172 		error = 0;
173 
174 		s = splnet();
175 
176 		IFADDR_FOREACH(ifa, ifp) {
177 			if (sockaddr_cmp(&u.sa, ifa->ifa_addr) == 0)
178 				break;
179 		}
180 
181 		switch (cmd) {
182 		case SIOCGLIFADDR:
183 			if ((iflr->flags & IFLR_PREFIX) == 0) {
184 				IFADDR_FOREACH(ifa, ifp) {
185 					if (ifa->ifa_addr->sa_family == AF_LINK)
186 						break;
187 				}
188 			}
189 			if (ifa == NULL) {
190 				error = EADDRNOTAVAIL;
191 				break;
192 			}
193 
194 			if (ifa == ifp->if_dl)
195 				iflr->flags = IFLR_ACTIVE;
196 			else
197 				iflr->flags = 0;
198 
199 			if (ifa == ifp->if_hwdl)
200 				iflr->flags |= IFLR_FACTORY;
201 
202 			sockaddr_copy(sstosa(&iflr->addr), sizeof(iflr->addr),
203 			    ifa->ifa_addr);
204 
205 			break;
206 		case SIOCDLIFADDR:
207 			if (ifa == NULL)
208 				error = EADDRNOTAVAIL;
209 			else if (ifa == ifp->if_dl || ifa == ifp->if_hwdl)
210 				error = EBUSY;
211 			else {
212 				/* TBD routing socket */
213 				rt_newaddrmsg(RTM_DELETE, ifa, 0, NULL);
214 				ifa_remove(ifp, ifa);
215 			}
216 			break;
217 		case SIOCALIFADDR:
218 			if (ifa != NULL)
219 				;
220 			else if ((ifa = if_dl_create(ifp, &nsdl)) == NULL) {
221 				error = ENOMEM;
222 				break;
223 			} else {
224 				sockaddr_copy(ifa->ifa_addr,
225 				    ifa->ifa_addr->sa_len, &u.sa);
226 				ifa_insert(ifp, ifa);
227 				rt_newaddrmsg(RTM_ADD, ifa, 0, NULL);
228 			}
229 
230 			mkactive = (iflr->flags & IFLR_ACTIVE) != 0;
231 			isactive = (ifa == ifp->if_dl);
232 
233 			if (!isactive && mkactive) {
234 				if_activate_sadl(ifp, ifa, nsdl);
235 				rt_newaddrmsg(RTM_CHANGE, ifa, 0, NULL);
236 				error = ENETRESET;
237 			}
238 			break;
239 		}
240 		splx(s);
241 		if (error != ENETRESET)
242 			return error;
243 		else if ((ifp->if_flags & IFF_RUNNING) != 0 &&
244 		         ifp->if_init != NULL)
245 			return (*ifp->if_init)(ifp);
246 		else
247 			return 0;
248 	default:
249 		return ENOTTY;
250 	}
251 }
252 
253 static int
254 link_attach(struct socket *so, int proto)
255 {
256 	sosetlock(so);
257 	KASSERT(solocked(so));
258 	return 0;
259 }
260 
261 static void
262 link_detach(struct socket *so)
263 {
264 	KASSERT(solocked(so));
265 	sofree(so);
266 }
267 
268 static int
269 link_accept(struct socket *so, struct mbuf *nam)
270 {
271 	KASSERT(solocked(so));
272 
273 	return EOPNOTSUPP;
274 }
275 
276 static int
277 link_bind(struct socket *so, struct mbuf *nam, struct lwp *l)
278 {
279 	KASSERT(solocked(so));
280 
281 	return EOPNOTSUPP;
282 }
283 
284 static int
285 link_listen(struct socket *so, struct lwp *l)
286 {
287 	KASSERT(solocked(so));
288 
289 	return EOPNOTSUPP;
290 }
291 
292 static int
293 link_connect(struct socket *so, struct mbuf *nam, struct lwp *l)
294 {
295  	KASSERT(solocked(so));
296 
297 	return EOPNOTSUPP;
298 }
299 
300 static int
301 link_connect2(struct socket *so, struct socket *so2)
302 {
303  	KASSERT(solocked(so));
304 
305 	return EOPNOTSUPP;
306 }
307 
308 static int
309 link_disconnect(struct socket *so)
310 {
311 	KASSERT(solocked(so));
312 
313 	return EOPNOTSUPP;
314 }
315 
316 static int
317 link_shutdown(struct socket *so)
318 {
319 	KASSERT(solocked(so));
320 
321 	return EOPNOTSUPP;
322 }
323 
324 static int
325 link_abort(struct socket *so)
326 {
327 	KASSERT(solocked(so));
328 
329 	return EOPNOTSUPP;
330 }
331 
332 static int
333 link_ioctl(struct socket *so, u_long cmd, void *nam, struct ifnet *ifp)
334 {
335 	return link_control(so, cmd, nam, ifp);
336 }
337 
338 static int
339 link_stat(struct socket *so, struct stat *ub)
340 {
341 	KASSERT(solocked(so));
342 
343 	return EOPNOTSUPP;
344 }
345 
346 static int
347 link_peeraddr(struct socket *so, struct mbuf *nam)
348 {
349 	KASSERT(solocked(so));
350 
351 	return EOPNOTSUPP;
352 }
353 
354 static int
355 link_sockaddr(struct socket *so, struct mbuf *nam)
356 {
357  	KASSERT(solocked(so));
358 
359 	return EOPNOTSUPP;
360 }
361 
362 static int
363 link_rcvd(struct socket *so, int flags, struct lwp *l)
364 {
365 	KASSERT(solocked(so));
366 
367 	return EOPNOTSUPP;
368 }
369 
370 static int
371 link_recvoob(struct socket *so, struct mbuf *m, int flags)
372 {
373 	KASSERT(solocked(so));
374 
375 	return EOPNOTSUPP;
376 }
377 
378 static int
379 link_send(struct socket *so, struct mbuf *m, struct mbuf *nam,
380     struct mbuf *control, struct lwp *l)
381 {
382 	KASSERT(solocked(so));
383 
384 	return EOPNOTSUPP;
385 }
386 
387 static int
388 link_sendoob(struct socket *so, struct mbuf *m, struct mbuf *control)
389 {
390 	KASSERT(solocked(so));
391 
392 	return EOPNOTSUPP;
393 }
394 
395 static int
396 link_purgeif(struct socket *so, struct ifnet *ifp)
397 {
398 
399 	return EOPNOTSUPP;
400 }
401 
402 static int
403 link_usrreq(struct socket *so, int req, struct mbuf *m, struct mbuf *nam,
404 	struct mbuf *control, struct lwp *l)
405 {
406 	KASSERT(req != PRU_ATTACH);
407 	KASSERT(req != PRU_DETACH);
408 	KASSERT(req != PRU_ACCEPT);
409 	KASSERT(req != PRU_BIND);
410 	KASSERT(req != PRU_LISTEN);
411 	KASSERT(req != PRU_CONNECT);
412 	KASSERT(req != PRU_CONNECT2);
413 	KASSERT(req != PRU_DISCONNECT);
414 	KASSERT(req != PRU_SHUTDOWN);
415 	KASSERT(req != PRU_ABORT);
416 	KASSERT(req != PRU_CONTROL);
417 	KASSERT(req != PRU_SENSE);
418 	KASSERT(req != PRU_PEERADDR);
419 	KASSERT(req != PRU_SOCKADDR);
420 	KASSERT(req != PRU_RCVD);
421 	KASSERT(req != PRU_RCVOOB);
422 	KASSERT(req != PRU_SEND);
423 	KASSERT(req != PRU_SENDOOB);
424 	KASSERT(req != PRU_PURGEIF);
425 
426 	return EOPNOTSUPP;
427 }
428 
429 /* Compare the field at byte offsets [fieldstart, fieldend) in
430  * two memory regions, [l, l + llen) and [r, r + llen).
431  */
432 static inline int
433 submemcmp(const void *l, const void *r,
434     const uint_fast8_t llen, const uint_fast8_t rlen,
435     const uint_fast8_t fieldstart, const uint_fast8_t fieldend)
436 {
437 	uint_fast8_t cmpend, minlen;
438 	const uint8_t *lb = l, *rb = r;
439 	int rc;
440 
441 	minlen = MIN(llen, rlen);
442 
443 	/* The field is missing from one region.  The shorter region is the
444 	 * lesser region.
445 	 */
446 	if (fieldstart >= minlen)
447 		return llen - rlen;
448 
449 	/* Two empty, present fields are always equal. */
450 	if (fieldstart > fieldend)
451 		return 0;
452 
453 	cmpend = MIN(fieldend, minlen);
454 
455 	rc = memcmp(&lb[fieldstart], &rb[fieldstart], cmpend - fieldstart);
456 
457 	if (rc != 0)
458 		return rc;
459 	/* If one or both fields are truncated, then the shorter is the lesser
460 	 * field.
461 	 */
462 	if (minlen < fieldend)
463 		return llen - rlen;
464 	/* Fields are full-length and equal.  The fields are equal. */
465 	return 0;
466 }
467 
468 uint8_t
469 sockaddr_dl_measure(uint8_t namelen, uint8_t addrlen)
470 {
471 	return offsetof(struct sockaddr_dl, sdl_data[namelen + addrlen]);
472 }
473 
474 struct sockaddr *
475 sockaddr_dl_alloc(uint16_t ifindex, uint8_t type,
476     const void *name, uint8_t namelen, const void *addr, uint8_t addrlen,
477     int flags)
478 {
479 	struct sockaddr *sa;
480 	socklen_t len;
481 
482 	len = sockaddr_dl_measure(namelen, addrlen);
483 	sa = sockaddr_alloc(AF_LINK, len, flags);
484 
485 	if (sa == NULL)
486 		return NULL;
487 
488 	if (sockaddr_dl_init(satosdl(sa), len, ifindex, type, name, namelen,
489 	    addr, addrlen) == NULL) {
490 		sockaddr_free(sa);
491 		return NULL;
492 	}
493 
494 	return sa;
495 }
496 
497 struct sockaddr_dl *
498 sockaddr_dl_init(struct sockaddr_dl *sdl, socklen_t socklen, uint16_t ifindex,
499     uint8_t type, const void *name, uint8_t namelen, const void *addr,
500     uint8_t addrlen)
501 {
502 	socklen_t len;
503 
504 	sdl->sdl_family = AF_LINK;
505 	sdl->sdl_slen = 0;
506 	len = sockaddr_dl_measure(namelen, addrlen);
507 	if (len > socklen) {
508 		sdl->sdl_len = socklen;
509 #ifdef DIAGNOSTIC
510 		printf("%s: too long: %u > %u\n", __func__, (u_int)len,
511 		    (u_int)socklen);
512 #endif
513 		return NULL;
514 	}
515 	sdl->sdl_len = len;
516 	sdl->sdl_index = ifindex;
517 	sdl->sdl_type = type;
518 	memset(&sdl->sdl_data[0], 0, namelen + addrlen);
519 	if (name != NULL) {
520 		memcpy(&sdl->sdl_data[0], name, namelen);
521 		sdl->sdl_nlen = namelen;
522 	} else
523 		sdl->sdl_nlen = 0;
524 	if (addr != NULL) {
525 		memcpy(&sdl->sdl_data[sdl->sdl_nlen], addr, addrlen);
526 		sdl->sdl_alen = addrlen;
527 	} else
528 		sdl->sdl_alen = 0;
529 	return sdl;
530 }
531 
532 static int
533 sockaddr_dl_cmp(const struct sockaddr *sa1, const struct sockaddr *sa2)
534 {
535 	int rc;
536 	const uint_fast8_t indexofs = offsetof(struct sockaddr_dl, sdl_index);
537 	const uint_fast8_t nlenofs = offsetof(struct sockaddr_dl, sdl_nlen);
538 	uint_fast8_t dataofs = offsetof(struct sockaddr_dl, sdl_data[0]);
539 	const struct sockaddr_dl *sdl1, *sdl2;
540 
541 	sdl1 = satocsdl(sa1);
542 	sdl2 = satocsdl(sa2);
543 
544 	rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len,
545 	    indexofs, nlenofs);
546 
547 	if (rc != 0)
548 		return rc;
549 
550 	rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len,
551 	    dataofs, dataofs + MIN(sdl1->sdl_nlen, sdl2->sdl_nlen));
552 
553 	if (rc != 0)
554 		return rc;
555 
556 	if (sdl1->sdl_nlen != sdl2->sdl_nlen)
557 		return sdl1->sdl_nlen - sdl2->sdl_nlen;
558 
559 	dataofs += sdl1->sdl_nlen;
560 
561 	rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len,
562 	    dataofs, dataofs + MIN(sdl1->sdl_alen, sdl2->sdl_alen));
563 
564 	if (rc != 0)
565 		return rc;
566 
567 	if (sdl1->sdl_alen != sdl2->sdl_alen)
568 		return sdl1->sdl_alen - sdl2->sdl_alen;
569 
570 	dataofs += sdl1->sdl_alen;
571 
572 	rc = submemcmp(sdl1, sdl2, sdl1->sdl_len, sdl2->sdl_len,
573 	    dataofs, dataofs + MIN(sdl1->sdl_slen, sdl2->sdl_slen));
574 
575 	if (sdl1->sdl_slen != sdl2->sdl_slen)
576 		return sdl1->sdl_slen - sdl2->sdl_slen;
577 
578 	return sdl1->sdl_len - sdl2->sdl_len;
579 }
580 
581 struct sockaddr_dl *
582 sockaddr_dl_setaddr(struct sockaddr_dl *sdl, socklen_t socklen,
583     const void *addr, uint8_t addrlen)
584 {
585 	socklen_t len;
586 
587 	len = sockaddr_dl_measure(sdl->sdl_nlen, addrlen);
588 	if (len > socklen) {
589 #ifdef DIAGNOSTIC
590 		printf("%s: too long: %u > %u\n", __func__, (u_int)len,
591 		    (u_int)socklen);
592 #endif
593 		return NULL;
594 	}
595 	memcpy(&sdl->sdl_data[sdl->sdl_nlen], addr, addrlen);
596 	sdl->sdl_alen = addrlen;
597 	sdl->sdl_len = len;
598 	return sdl;
599 }
600