1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2002 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 /*
31  * Portions of this source code were derived from Berkeley 4.3 BSD
32  * under license from the Regents of the University of California.
33  */
34 
35 #pragma ident	"%Z%%M%	%I%	%E% SMI"
36 
37 #include "defs.h"
38 
39 #define	IF_SEPARATOR	':'
40 
41 struct interface	*ifnet;
42 
43 static int		setup_listen_sock(int ifindex);
44 static void		addrouteforif(struct interface *ifp);
45 static void		resetup_listen_sock(struct interface *, int);
46 
47 /*
48  * This is called at startup and after that, every CHECK_INTERVAL seconds or
49  * when a SIGHUP is received.
50  */
51 void
initifs(void)52 initifs(void)
53 {
54 	static char *buf = NULL;
55 	static uint_t maxbufsize = 0;
56 	int bufsize;
57 	int numifs;
58 	struct lifnum lifn;
59 	struct lifconf lifc;
60 	struct lifreq lifr;
61 	struct lifreq *lifrp;
62 	int n;
63 	struct interface ifs;
64 	struct interface *ifp;
65 	int netmaskchange = 0;
66 	boolean_t changes = _B_FALSE;
67 
68 	lifn.lifn_family = AF_INET6;
69 	lifn.lifn_flags = 0;
70 	if (ioctl(iocsoc, SIOCGLIFNUM, (char *)&lifn) < 0) {
71 		syslog(LOG_ERR, "initifs: ioctl (get interface numbers): %m");
72 		return;
73 	}
74 	numifs = lifn.lifn_count;
75 	bufsize = numifs * sizeof (struct lifreq);
76 
77 	if (buf == NULL || bufsize > maxbufsize) {
78 		if (buf != NULL)
79 			free(buf);
80 		maxbufsize = bufsize;
81 		buf = (char *)malloc(maxbufsize);
82 		if (buf == NULL) {
83 			syslog(LOG_ERR, "initifs: out of memory");
84 			return;
85 		}
86 	}
87 
88 	lifc.lifc_family = AF_INET6;
89 	lifc.lifc_flags = 0;
90 	lifc.lifc_len = bufsize;
91 	lifc.lifc_buf = buf;
92 	if (ioctl(iocsoc, SIOCGLIFCONF, (char *)&lifc) < 0) {
93 		syslog(LOG_ERR,
94 		    "initifs: ioctl (get interface configuration): %m");
95 		return;
96 	}
97 
98 	/*
99 	 * Mark all of the currently known interfaces in order to determine
100 	 * which of the these interfaces no longer exist.
101 	 */
102 	for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next)
103 		ifp->int_flags |= RIP6_IFF_MARKED;
104 	lifrp = lifc.lifc_req;
105 	for (n = lifc.lifc_len / sizeof (struct lifreq); n > 0; n--, lifrp++) {
106 		bzero((char *)&ifs, sizeof (ifs));
107 		(void) strncpy(lifr.lifr_name, lifrp->lifr_name,
108 		    sizeof (lifr.lifr_name));
109 		if (ioctl(iocsoc, SIOCGLIFFLAGS, (char *)&lifr) < 0) {
110 			syslog(LOG_ERR,
111 			    "initifs: ioctl (get interface flags): %m");
112 			continue;
113 		}
114 		if (!(lifr.lifr_flags & IFF_IPV6) ||
115 		    !(lifr.lifr_flags & IFF_MULTICAST) ||
116 		    (lifr.lifr_flags & IFF_LOOPBACK))
117 			continue;
118 
119 		ifp = if_ifwithname(lifr.lifr_name);
120 		if (ifp != NULL)
121 			ifp->int_flags &= ~RIP6_IFF_MARKED;
122 		if (lifr.lifr_flags & IFF_POINTOPOINT)
123 			ifs.int_flags |= RIP6_IFF_POINTOPOINT;
124 		if (lifr.lifr_flags & IFF_NORTEXCH)
125 			ifs.int_flags |= RIP6_IFF_NORTEXCH;
126 		if (lifr.lifr_flags & IFF_PRIVATE)
127 			ifs.int_flags |= RIP6_IFF_PRIVATE;
128 		if (lifr.lifr_flags & IFF_UP) {
129 			ifs.int_flags |= RIP6_IFF_UP;
130 		} else {
131 			if (ifp != NULL) {
132 				if (ifp->int_flags & RIP6_IFF_UP) {
133 					/*
134 					 * If there is an transition from up to
135 					 * down for an exisiting interface,
136 					 * increment the counter.
137 					 */
138 					ifp->int_transitions++;
139 					changes = _B_TRUE;
140 				}
141 				if_purge(ifp);
142 			}
143 			continue;
144 		}
145 
146 		if (ifs.int_flags & RIP6_IFF_POINTOPOINT) {
147 			/*
148 			 * For point-to-point interfaces, retrieve both the
149 			 * local and the remote addresses.
150 			 */
151 			if (ioctl(iocsoc, SIOCGLIFADDR, (char *)&lifr) < 0) {
152 				syslog(LOG_ERR,
153 				    "initifs: ioctl (get interface address): "
154 				    "%m");
155 				continue;
156 			}
157 			ifs.int_addr =
158 			    ((struct sockaddr_in6 *)&lifr.lifr_addr)->sin6_addr;
159 			if (ioctl(iocsoc, SIOCGLIFDSTADDR, (char *)&lifr) < 0) {
160 				syslog(LOG_ERR,
161 				    "initifs: ioctl (get destination address): "
162 				    "%m");
163 				continue;
164 			}
165 			ifs.int_dstaddr = ((struct sockaddr_in6 *)
166 			    &lifr.lifr_dstaddr)->sin6_addr;
167 			ifs.int_prefix_length = IPV6_ABITS;
168 		} else {
169 			/*
170 			 * For other interfaces, retreieve the prefix (including
171 			 * the prefix length.
172 			 */
173 			if (ioctl(iocsoc, SIOCGLIFSUBNET, (char *)&lifr) < 0) {
174 				syslog(LOG_ERR,
175 				    "initifs: ioctl (get subnet prefix): %m");
176 				continue;
177 			}
178 			/*
179 			 * This should never happen but check for it in any case
180 			 * since the kernel stores it as an signed integer.
181 			 */
182 			if (lifr.lifr_addrlen < 0 ||
183 			    lifr.lifr_addrlen > IPV6_ABITS) {
184 				syslog(LOG_ERR,
185 				    "initifs: ioctl (get subnet prefix) "
186 				    "returned invalid prefix length of %d",
187 				    lifr.lifr_addrlen);
188 				continue;
189 			}
190 			ifs.int_prefix_length = lifr.lifr_addrlen;
191 			ifs.int_addr = ((struct sockaddr_in6 *)
192 			    &lifr.lifr_subnet)->sin6_addr;
193 		}
194 
195 		if (ioctl(iocsoc, SIOCGLIFMETRIC, (char *)&lifr) < 0 ||
196 		    lifr.lifr_metric < 0)
197 			ifs.int_metric = 1;
198 		else
199 			ifs.int_metric = lifr.lifr_metric + 1;
200 
201 		if (ioctl(iocsoc, SIOCGLIFINDEX, (char *)&lifr) < 0) {
202 			syslog(LOG_ERR, "initifs: ioctl (get index): %m");
203 			continue;
204 		}
205 		ifs.int_ifindex = lifr.lifr_index;
206 
207 		if (ioctl(iocsoc, SIOCGLIFMTU, (char *)&lifr) < 0) {
208 			syslog(LOG_ERR, "initifs: ioctl (get mtu): %m");
209 			continue;
210 		}
211 
212 		/*
213 		 * If the interface's recorded MTU doesn't make sense, use
214 		 * IPV6_MIN_MTU instead.
215 		 */
216 		if (lifr.lifr_mtu < IPV6_MIN_MTU)
217 			ifs.int_mtu = IPV6_MIN_MTU;
218 		else
219 			ifs.int_mtu = lifr.lifr_mtu;
220 
221 		if (ifp != NULL) {
222 			/*
223 			 * RIP6_IFF_NORTEXCH flag change by itself shouldn't
224 			 * cause an if_purge() call, which also purges all the
225 			 * routes heard off this interface. So, let's suppress
226 			 * changes of RIP6_IFF_NORTEXCH	in the following
227 			 * comparisons.
228 			 */
229 			if (ifp->int_prefix_length == ifs.int_prefix_length &&
230 			    ((ifp->int_flags | RIP6_IFF_NORTEXCH) ==
231 			    (ifs.int_flags | RIP6_IFF_NORTEXCH)) &&
232 			    ifp->int_metric == ifs.int_metric &&
233 			    ifp->int_ifindex == ifs.int_ifindex) {
234 				/*
235 				 * Now let's make sure we capture the latest
236 				 * value of RIP6_IFF_NORTEXCH flag.
237 				 */
238 				if (ifs.int_flags & RIP6_IFF_NORTEXCH)
239 					ifp->int_flags |= RIP6_IFF_NORTEXCH;
240 				else
241 					ifp->int_flags &= ~RIP6_IFF_NORTEXCH;
242 
243 				if (!(ifp->int_flags & RIP6_IFF_POINTOPOINT) &&
244 				    IN6_ARE_ADDR_EQUAL(&ifp->int_addr,
245 					&ifs.int_addr))
246 					continue;
247 				if ((ifp->int_flags & RIP6_IFF_POINTOPOINT) &&
248 				    IN6_ARE_ADDR_EQUAL(&ifp->int_dstaddr,
249 					&ifs.int_dstaddr))
250 					continue;
251 			}
252 			if_purge(ifp);
253 			if (ifp->int_prefix_length != ifs.int_prefix_length)
254 				netmaskchange = 1;
255 			ifp->int_addr = ifs.int_addr;
256 			ifp->int_dstaddr = ifs.int_dstaddr;
257 			ifp->int_metric = ifs.int_metric;
258 			/*
259 			 * If there is an transition from down to up for an
260 			 * exisiting interface, increment the counter.
261 			 */
262 			if (!(ifp->int_flags & RIP6_IFF_UP) &&
263 			    (ifs.int_flags & RIP6_IFF_UP))
264 				ifp->int_transitions++;
265 			ifp->int_flags |= ifs.int_flags;
266 			ifp->int_prefix_length = ifs.int_prefix_length;
267 
268 			/*
269 			 * If the interface index has changed, we may need to
270 			 * set up the listen socket again.
271 			 */
272 			if (ifp->int_ifindex != ifs.int_ifindex) {
273 				if (ifp->int_sock != -1) {
274 					resetup_listen_sock(ifp,
275 					    ifs.int_ifindex);
276 				}
277 				ifp->int_ifindex = ifs.int_ifindex;
278 			}
279 
280 			ifp->int_mtu = ifs.int_mtu;
281 		} else {
282 			char *cp;
283 			int log_num;
284 
285 			ifp = (struct interface *)
286 			    malloc(sizeof (struct interface));
287 			if (ifp == NULL) {
288 				syslog(LOG_ERR, "initifs: out of memory");
289 				return;
290 			}
291 			*ifp = ifs;
292 			ifp->int_name = ifp->int_ifbase = NULL;
293 			ifp->int_name =
294 			    (char *)malloc((size_t)strlen(lifr.lifr_name) + 1);
295 			if (ifp->int_name == NULL) {
296 				free(ifp);
297 				syslog(LOG_ERR, "initifs: out of memory");
298 				return;
299 			}
300 			(void) strcpy(ifp->int_name, lifr.lifr_name);
301 			ifp->int_ifbase =
302 			    (char *)malloc((size_t)strlen(lifr.lifr_name) + 1);
303 			if (ifp->int_ifbase == NULL) {
304 				free(ifp->int_name);
305 				free(ifp);
306 				syslog(LOG_ERR, "initifs: out of memory");
307 				return;
308 			}
309 			(void) strcpy(ifp->int_ifbase, lifr.lifr_name);
310 			cp = (char *)index(ifp->int_ifbase, IF_SEPARATOR);
311 			if (cp != NULL) {
312 				/*
313 				 * Verify that the value following the separator
314 				 * is an integer greater than zero (the only
315 				 * possible value for a logical interface).
316 				 */
317 				log_num = atoi((char *)(cp + 1));
318 				if (log_num <= 0) {
319 					free(ifp->int_ifbase);
320 					free(ifp->int_name);
321 					free(ifp);
322 					syslog(LOG_ERR,
323 					    "initifs: interface name %s could "
324 					    "not be parsed", ifp->int_name);
325 					return;
326 				}
327 				*cp = '\0';
328 			} else {
329 				log_num = 0;
330 			}
331 			if (log_num == 0) {
332 				ifp->int_sock =
333 				    setup_listen_sock(ifp->int_ifindex);
334 			} else {
335 				ifp->int_sock = -1;
336 			}
337 			ifp->int_next = ifnet;
338 			ifnet = ifp;
339 			traceinit(ifp);
340 		}
341 		addrouteforif(ifp);
342 		changes = _B_TRUE;
343 	}
344 
345 	/*
346 	 * Any remaining interfaces that are still marked and which were in an
347 	 * up state (RIP6_IFF_UP) need to removed from the routing table.
348 	 */
349 	for (ifp = ifnet; ifp != NULL; ifp = ifp->int_next) {
350 		if ((ifp->int_flags & (RIP6_IFF_MARKED | RIP6_IFF_UP)) ==
351 		    (RIP6_IFF_MARKED | RIP6_IFF_UP)) {
352 			if_purge(ifp);
353 			ifp->int_flags &= ~RIP6_IFF_MARKED;
354 			changes = _B_TRUE;
355 		}
356 	}
357 	if (netmaskchange)
358 		rtchangeall();
359 	if (supplier & changes)
360 		dynamic_update((struct interface *)NULL);
361 }
362 
363 static void
addrouteforif(struct interface * ifp)364 addrouteforif(struct interface *ifp)
365 {
366 	struct rt_entry *rt;
367 	struct in6_addr *dst;
368 
369 	if (ifp->int_flags & RIP6_IFF_POINTOPOINT)
370 		dst = &ifp->int_dstaddr;
371 	else
372 		dst = &ifp->int_addr;
373 
374 	rt = rtlookup(dst, ifp->int_prefix_length);
375 
376 	if (rt != NULL) {
377 		if (rt->rt_state & RTS_INTERFACE)
378 			return;
379 		rtdelete(rt);
380 	}
381 	rtadd(dst, &ifp->int_addr, ifp->int_prefix_length, ifp->int_metric, 0,
382 	    _B_TRUE, ifp);
383 }
384 
385 static int
setup_listen_sock(int ifindex)386 setup_listen_sock(int ifindex)
387 {
388 	int sock;
389 	struct sockaddr_in6 sin6;
390 	uint_t hops;
391 	struct ipv6_mreq allrouters_mreq;
392 	int on = 1;
393 	int off = 0;
394 	int recvsize;
395 
396 	sock = socket(AF_INET6, SOCK_DGRAM, 0);
397 	if (sock == -1)
398 		goto sock_fail;
399 
400 	if (setsockopt(sock, IPPROTO_IPV6, IPV6_BOUND_IF, (char *)&ifindex,
401 	    sizeof (ifindex)) < 0) {
402 		syslog(LOG_ERR,
403 		    "setup_listen_sock: setsockopt: IPV6_BOUND_IF: %m");
404 		goto sock_fail;
405 	}
406 
407 	hops = IPV6_MAX_HOPS;
408 	if (setsockopt(sock, IPPROTO_IPV6, IPV6_UNICAST_HOPS, (char *)&hops,
409 	    sizeof (hops)) < 0) {
410 		syslog(LOG_ERR,
411 		    "setup_listen_sock: setsockopt: IPV6_UNICAST_HOPS: %m");
412 		goto sock_fail;
413 	}
414 
415 	if (setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, (char *)&hops,
416 	    sizeof (hops)) < 0) {
417 		syslog(LOG_ERR,
418 		    "setup_listen_sock: setsockopt: IPV6_MULTICAST_HOPS: %m");
419 		goto sock_fail;
420 	}
421 
422 	if (setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, (char *)&off,
423 	    sizeof (off)) < 0) {
424 		syslog(LOG_ERR,
425 		    "setup_listen_sock: setsockopt: IPV6_MULTICAST_LOOP: %m");
426 		goto sock_fail;
427 	}
428 
429 	allrouters_mreq.ipv6mr_multiaddr = allrouters_in6;
430 	allrouters_mreq.ipv6mr_interface = ifindex;
431 	if (setsockopt(sock, IPPROTO_IPV6, IPV6_JOIN_GROUP,
432 	    (char *)&allrouters_mreq, sizeof (allrouters_mreq)) < 0) {
433 		if (errno != EADDRINUSE) {
434 			syslog(LOG_ERR,
435 			    "setup_listen_sock: setsockopt: "
436 			    "IPV6_JOIN_GROUP: %m");
437 			goto sock_fail;
438 		}
439 	}
440 
441 	if (setsockopt(sock, IPPROTO_IPV6, IPV6_RECVHOPLIMIT, (char *)&on,
442 	    sizeof (off)) < 0) {
443 		syslog(LOG_ERR,
444 		    "setup_listen_sock: setsockopt: IPV6_RECVHOPLIMIT: %m");
445 		goto sock_fail;
446 	}
447 
448 	if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (char *)&on,
449 	    sizeof (on)) < 0) {
450 		syslog(LOG_ERR,
451 		    "setup_listen_sock: setsockopt: SO_REUSEADDR: %m");
452 		goto sock_fail;
453 	}
454 
455 	recvsize = RCVBUFSIZ;
456 	if (setsockopt(sock, SOL_SOCKET, SO_RCVBUF, (char *)&recvsize,
457 	    sizeof (int)) < 0) {
458 		syslog(LOG_ERR, "setup_listen_sock: setsockopt: SO_RCVBUF: %m");
459 		goto sock_fail;
460 	}
461 
462 	bzero((char *)&sin6, sizeof (sin6));
463 	sin6.sin6_family = AF_INET6;
464 	sin6.sin6_port = rip6_port;
465 	if (bind(sock, (struct sockaddr *)&sin6, sizeof (sin6)) < 0) {
466 		syslog(LOG_ERR, "setup_listen_sock: bind: %m");
467 		goto sock_fail;
468 	}
469 
470 	poll_ifs_num++;
471 	if (poll_ifs == NULL) {
472 		poll_ifs = (struct pollfd *)
473 		    malloc(max_poll_ifs * sizeof (struct pollfd));
474 	} else if (poll_ifs_num > max_poll_ifs) {
475 		max_poll_ifs *= 2;
476 		poll_ifs = (struct pollfd *)realloc((char *)poll_ifs,
477 		    max_poll_ifs * sizeof (struct pollfd));
478 	}
479 	if (poll_ifs == NULL) {
480 		syslog(LOG_ERR, "setup_listen_sock: out of memory");
481 		goto sock_fail;
482 	}
483 
484 	poll_ifs[poll_ifs_num - 1].fd = sock;
485 	poll_ifs[poll_ifs_num - 1].events = POLLIN;
486 	return (sock);
487 
488 sock_fail:
489 	if (sock > 0)
490 		(void) close(sock);
491 	return (-1);
492 }
493 
494 /*
495  * resetup_listen_sock is primarily used in the case where a tunnel was
496  * plumbed, unplumbed, then plumbed again.  This would cause the binding set by
497  * IPV6_BOUND_IF to be useless, and sends to the associated socket will be
498  * transmitted on the wrong interface.  resetup_listen_sock
499  *	closes the socket,
500  *	removes the socket from poll_ifs[]
501  *	plugs the hole in poll_ifs[]
502  *	calls setup_listen_sock to set up the socket again
503  */
504 void
resetup_listen_sock(struct interface * ifp,int newindex)505 resetup_listen_sock(struct interface *ifp, int newindex)
506 {
507 	int i;
508 
509 	(void) close(ifp->int_sock);
510 
511 	/* Remove socket from poll_ifs[]. */
512 	for (i = poll_ifs_num - 1; i >= 0; i--) {
513 
514 		if (poll_ifs[i].fd == ifp->int_sock) {
515 
516 			poll_ifs[i].fd = 0;
517 			poll_ifs[i].events = 0;
518 
519 			/*
520 			 * Remove hole in poll_ifs.  Possibly exchange
521 			 * poll_ifs[i] with poll_ifs[poll_ifs_num-1].
522 			 */
523 			if (i != poll_ifs_num - 1) {
524 				poll_ifs[i] = poll_ifs[poll_ifs_num - 1];
525 				poll_ifs[poll_ifs_num - 1].fd = 0;
526 				poll_ifs[poll_ifs_num - 1].events = 0;
527 			}
528 			poll_ifs_num--;
529 
530 			/* Now set everything up again. */
531 			ifp->int_sock = setup_listen_sock(newindex);
532 			break;
533 		}
534 	}
535 }
536