1 /* $NetBSD: rsrr.c,v 1.10 2008/08/26 17:38:21 seanb Exp $ */
2
3 /*
4 * Copyright (c) 1993, 1998-2001.
5 * The University of Southern California/Information Sciences Institute.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the project nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33 /* RSRR code written by Daniel Zappala, USC Information Sciences Institute,
34 * April 1995.
35 */
36
37 /* May 1995 -- Added support for Route Change Notification */
38
39 #ifdef RSRR
40
41 #include "defs.h"
42 #include <sys/param.h>
43 #if (defined(BSD) && (BSD >= 199103))
44 #include <stddef.h>
45 #endif
46
47 /* Taken from prune.c */
48 /*
49 * checks for scoped multicast addresses
50 */
51 #define GET_SCOPE(gt) { \
52 int _i; \
53 if (((gt)->gt_mcastgrp & 0xff000000) == 0xef000000) \
54 for (_i = 0; _i < numvifs; _i++) \
55 if (scoped_addr(_i, (gt)->gt_mcastgrp)) \
56 VIFM_SET(_i, (gt)->gt_scope); \
57 }
58
59 /*
60 * Exported variables.
61 */
62 int rsrr_socket; /* interface to reservation protocol */
63
64 /*
65 * Global RSRR variables.
66 */
67 char rsrr_recv_buf[RSRR_MAX_LEN]; /* RSRR receive buffer */
68 char rsrr_send_buf[RSRR_MAX_LEN]; /* RSRR send buffer */
69
70 struct sockaddr_un client_addr;
71 socklen_t client_length = sizeof(client_addr);
72
73
74 /*
75 * Procedure definitions needed internally.
76 */
77 static void rsrr_accept(int recvlen);
78 static void rsrr_accept_iq(void);
79 static int rsrr_accept_rq(struct rsrr_rq *route_query, int flags,
80 struct gtable *gt_notify);
81 static int rsrr_send(int sendlen);
82 static void rsrr_cache(struct gtable *gt, struct rsrr_rq *route_query);
83
84 /* Initialize RSRR socket */
85 void
rsrr_init()86 rsrr_init()
87 {
88 int servlen;
89 struct sockaddr_un serv_addr;
90
91 if ((rsrr_socket = socket(AF_LOCAL, SOCK_DGRAM, 0)) < 0)
92 logit(LOG_ERR, errno, "Can't create RSRR socket");
93
94 unlink(RSRR_SERV_PATH);
95 bzero((char *) &serv_addr, sizeof(serv_addr));
96 serv_addr.sun_family = AF_LOCAL;
97 strlcpy(serv_addr.sun_path, RSRR_SERV_PATH, sizeof(serv_addr.sun_path));
98 #if (defined(BSD) && (BSD >= 199103))
99 servlen = offsetof(struct sockaddr_un, sun_path) +
100 strlen(serv_addr.sun_path);
101 serv_addr.sun_len = servlen;
102 #else
103 servlen = sizeof(serv_addr.sun_family) + strlen(serv_addr.sun_path);
104 #endif
105
106 if (bind(rsrr_socket, (struct sockaddr *) &serv_addr, servlen) < 0)
107 logit(LOG_ERR, errno, "Can't bind RSRR socket");
108
109 if (register_input_handler(rsrr_socket,rsrr_read) < 0)
110 logit(LOG_WARNING, 0, "Couldn't register RSRR as an input handler");
111 }
112
113 /* Read a message from the RSRR socket */
114 void
rsrr_read(f,rfd)115 rsrr_read(f, rfd)
116 int f;
117 fd_set *rfd;
118 {
119 int rsrr_recvlen;
120 int omask;
121
122 bzero((char *) &client_addr, sizeof(client_addr));
123 rsrr_recvlen = recvfrom(rsrr_socket, rsrr_recv_buf, sizeof(rsrr_recv_buf),
124 0, (struct sockaddr *)&client_addr, &client_length);
125 if (rsrr_recvlen < 0) {
126 if (errno != EINTR)
127 logit(LOG_ERR, errno, "RSRR recvfrom");
128 return;
129 }
130 /* Use of omask taken from main() */
131 omask = sigblock(sigmask(SIGALRM));
132 rsrr_accept(rsrr_recvlen);
133 (void)sigsetmask(omask);
134 }
135
136 /* Accept a message from the reservation protocol and take
137 * appropriate action.
138 */
139 static void
rsrr_accept(recvlen)140 rsrr_accept(recvlen)
141 int recvlen;
142 {
143 struct rsrr_header *rsrr;
144 struct rsrr_rq *route_query;
145
146 if (recvlen < RSRR_HEADER_LEN) {
147 logit(LOG_WARNING, 0,
148 "Received RSRR packet of %d bytes, which is less than min size",
149 recvlen);
150 return;
151 }
152
153 rsrr = (struct rsrr_header *) rsrr_recv_buf;
154
155 if (rsrr->version > RSRR_MAX_VERSION) {
156 logit(LOG_WARNING, 0,
157 "Received RSRR packet version %d, which I don't understand",
158 rsrr->version);
159 return;
160 }
161
162 switch (rsrr->version) {
163 case 1:
164 switch (rsrr->type) {
165 case RSRR_INITIAL_QUERY:
166 /* Send Initial Reply to client */
167 logit(LOG_INFO, 0, "Received Initial Query\n");
168 rsrr_accept_iq();
169 break;
170 case RSRR_ROUTE_QUERY:
171 /* Check size */
172 if (recvlen < RSRR_RQ_LEN) {
173 logit(LOG_WARNING, 0,
174 "Received Route Query of %d bytes, which is too small",
175 recvlen);
176 break;
177 }
178 /* Get the query */
179 route_query = (struct rsrr_rq *) (rsrr_recv_buf + RSRR_HEADER_LEN);
180 logit(LOG_INFO, 0,
181 "Received Route Query for src %s grp %s notification %d",
182 inet_fmt(route_query->source_addr.s_addr),
183 inet_fmt(route_query->dest_addr.s_addr),
184 BIT_TST(rsrr->flags,RSRR_NOTIFICATION_BIT));
185 /* Send Route Reply to client */
186 rsrr_accept_rq(route_query,rsrr->flags,NULL);
187 break;
188 default:
189 logit(LOG_WARNING, 0,
190 "Received RSRR packet type %d, which I don't handle",
191 rsrr->type);
192 break;
193 }
194 break;
195
196 default:
197 logit(LOG_WARNING, 0,
198 "Received RSRR packet version %d, which I don't understand",
199 rsrr->version);
200 break;
201 }
202 }
203
204 /* Send an Initial Reply to the reservation protocol. */
205 static void
rsrr_accept_iq()206 rsrr_accept_iq()
207 {
208 struct rsrr_header *rsrr;
209 struct rsrr_vif *vif_list;
210 struct uvif *v;
211 int vifi, sendlen;
212
213 /* Check for space. There should be room for plenty of vifs,
214 * but we should check anyway.
215 */
216 if (numvifs > RSRR_MAX_VIFS) {
217 logit(LOG_WARNING, 0,
218 "Can't send RSRR Route Reply because %d is too many vifs",
219 numvifs);
220 return;
221 }
222
223 /* Set up message */
224 rsrr = (struct rsrr_header *) rsrr_send_buf;
225 rsrr->version = 1;
226 rsrr->type = RSRR_INITIAL_REPLY;
227 rsrr->flags = 0;
228 rsrr->num = numvifs;
229
230 vif_list = (struct rsrr_vif *) (rsrr_send_buf + RSRR_HEADER_LEN);
231
232 /* Include the vif list. */
233 for (vifi=0, v = uvifs; vifi < numvifs; vifi++, v++) {
234 vif_list[vifi].id = vifi;
235 vif_list[vifi].status = 0;
236 if (v->uv_flags & VIFF_DISABLED)
237 BIT_SET(vif_list[vifi].status,RSRR_DISABLED_BIT);
238 vif_list[vifi].threshold = v->uv_threshold;
239 vif_list[vifi].local_addr.s_addr = v->uv_lcl_addr;
240 }
241
242 /* Get the size. */
243 sendlen = RSRR_HEADER_LEN + numvifs*RSRR_VIF_LEN;
244
245 /* Send it. */
246 logit(LOG_INFO, 0, "Send RSRR Initial Reply");
247 rsrr_send(sendlen);
248 }
249
250 /* Send a Route Reply to the reservation protocol. The Route Query
251 * contains the query to which we are responding. The flags contain
252 * the incoming flags from the query or, for route change
253 * notification, the flags that should be set for the reply. The
254 * kernel table entry contains the routing info to use for a route
255 * change notification.
256 */
257 static int
rsrr_accept_rq(route_query,flags,gt_notify)258 rsrr_accept_rq(route_query,flags,gt_notify)
259 struct rsrr_rq *route_query;
260 int flags;
261 struct gtable *gt_notify;
262 {
263 struct rsrr_header *rsrr;
264 struct rsrr_rr *route_reply;
265 struct gtable *gt,local_g;
266 struct rtentry *r;
267 int sendlen,i;
268 u_long mcastgrp;
269
270 /* Set up message */
271 rsrr = (struct rsrr_header *) rsrr_send_buf;
272 rsrr->version = 1;
273 rsrr->type = RSRR_ROUTE_REPLY;
274 rsrr->flags = 0;
275 rsrr->num = 0;
276
277 route_reply = (struct rsrr_rr *) (rsrr_send_buf + RSRR_HEADER_LEN);
278 route_reply->dest_addr.s_addr = route_query->dest_addr.s_addr;
279 route_reply->source_addr.s_addr = route_query->source_addr.s_addr;
280 route_reply->query_id = route_query->query_id;
281
282 /* Blank routing entry for error. */
283 route_reply->in_vif = 0;
284 route_reply->reserved = 0;
285 route_reply->out_vif_bm = 0;
286
287 /* Get the size. */
288 sendlen = RSRR_RR_LEN;
289
290 /* If kernel table entry is defined, then we are sending a Route Reply
291 * due to a Route Change Notification event. Use the kernel table entry
292 * to supply the routing info.
293 */
294 if (gt_notify) {
295 /* Set flags */
296 rsrr->flags = flags;
297 /* Include the routing entry. */
298 route_reply->in_vif = gt_notify->gt_route->rt_parent;
299 route_reply->out_vif_bm = gt_notify->gt_grpmems;
300
301 } else if (find_src_grp(route_query->source_addr.s_addr, 0,
302 route_query->dest_addr.s_addr)) {
303
304 /* Found kernel entry. Code taken from add_table_entry() */
305 gt = gtp ? gtp->gt_gnext : kernel_table;
306
307 /* Include the routing entry. */
308 route_reply->in_vif = gt->gt_route->rt_parent;
309 route_reply->out_vif_bm = gt->gt_grpmems;
310
311 /* Cache reply if using route change notification. */
312 if BIT_TST(flags,RSRR_NOTIFICATION_BIT) {
313 rsrr_cache(gt,route_query);
314 BIT_SET(rsrr->flags,RSRR_NOTIFICATION_BIT);
315 }
316
317 } else {
318 /* No kernel entry; use routing table. */
319 r = determine_route(route_query->source_addr.s_addr);
320
321 if (r != NULL) {
322 /* We need to mimic what will happen if a data packet
323 * is forwarded by multicast routing -- the kernel will
324 * make an upcall and mrouted will install a route in the kernel.
325 * Our outgoing vif bitmap should reflect what that table
326 * will look like. Grab code from add_table_entry().
327 * This is gross, but it's probably better to be accurate.
328 */
329
330 gt = &local_g;
331 mcastgrp = route_query->dest_addr.s_addr;
332
333 gt->gt_mcastgrp = mcastgrp;
334 gt->gt_grpmems = 0;
335 gt->gt_scope = 0;
336 gt->gt_route = r;
337
338 /* obtain the multicast group membership list */
339 for (i = 0; i < numvifs; i++) {
340 if (VIFM_ISSET(i, r->rt_children) &&
341 !(VIFM_ISSET(i, r->rt_leaves)))
342 VIFM_SET(i, gt->gt_grpmems);
343
344 if (VIFM_ISSET(i, r->rt_leaves) && grplst_mem(i, mcastgrp))
345 VIFM_SET(i, gt->gt_grpmems);
346 }
347
348 GET_SCOPE(gt);
349 gt->gt_grpmems &= ~gt->gt_scope;
350
351 /* Include the routing entry. */
352 route_reply->in_vif = gt->gt_route->rt_parent;
353 route_reply->out_vif_bm = gt->gt_grpmems;
354
355 } else {
356 /* Set error bit. */
357 BIT_SET(rsrr->flags,RSRR_ERROR_BIT);
358 }
359 }
360
361 if (gt_notify)
362 logit(LOG_INFO, 0, "Route Change: Send RSRR Route Reply");
363
364 else
365 logit(LOG_INFO, 0, "Send RSRR Route Reply");
366
367 logit(LOG_INFO, 0, "for src %s dst %s in vif %d out vif %lu\n",
368 inet_fmt(route_reply->source_addr.s_addr),
369 inet_fmt(route_reply->dest_addr.s_addr),
370 route_reply->in_vif, route_reply->out_vif_bm);
371
372 /* Send it. */
373 return rsrr_send(sendlen);
374 }
375
376 /* Send an RSRR message. */
377 static int
rsrr_send(sendlen)378 rsrr_send(sendlen)
379 int sendlen;
380 {
381 int error;
382
383 /* Send it. */
384 error = sendto(rsrr_socket, rsrr_send_buf, sendlen, 0,
385 (struct sockaddr *)&client_addr, client_length);
386
387 /* Check for errors. */
388 if (error < 0) {
389 logit(LOG_WARNING, errno, "Failed send on RSRR socket");
390 } else if (error != sendlen) {
391 logit(LOG_WARNING, 0,
392 "Sent only %d out of %d bytes on RSRR socket\n", error, sendlen);
393 }
394 return error;
395 }
396
397 /* Cache a message being sent to a client. Currently only used for
398 * caching Route Reply messages for route change notification.
399 */
400 static void
rsrr_cache(gt,route_query)401 rsrr_cache(gt,route_query)
402 struct gtable *gt;
403 struct rsrr_rq *route_query;
404 {
405 struct rsrr_cache *rc, **rcnp;
406 struct rsrr_header *rsrr;
407
408 rsrr = (struct rsrr_header *) rsrr_send_buf;
409
410 rcnp = >->gt_rsrr_cache;
411 while ((rc = *rcnp) != NULL) {
412 if ((rc->route_query.source_addr.s_addr ==
413 route_query->source_addr.s_addr) &&
414 (rc->route_query.dest_addr.s_addr ==
415 route_query->dest_addr.s_addr) &&
416 (!strcmp(rc->client_addr.sun_path,client_addr.sun_path))) {
417 /* Cache entry already exists.
418 * Check if route notification bit has been cleared.
419 */
420 if (!BIT_TST(rsrr->flags,RSRR_NOTIFICATION_BIT)) {
421 /* Delete cache entry. */
422 *rcnp = rc->next;
423 free(rc);
424 } else {
425 /* Update */
426 rc->route_query.query_id = route_query->query_id;
427 logit(LOG_DEBUG, 0,
428 "Update cached query id %ld from client %s\n",
429 rc->route_query.query_id, rc->client_addr.sun_path);
430 }
431 return;
432 }
433 rcnp = &rc->next;
434 }
435
436 /* Cache entry doesn't already exist. Create one and insert at
437 * front of list.
438 */
439 rc = (struct rsrr_cache *) malloc(sizeof(struct rsrr_cache));
440 if (rc == NULL)
441 logit(LOG_ERR, 0, "ran out of memory");
442 rc->route_query.source_addr.s_addr = route_query->source_addr.s_addr;
443 rc->route_query.dest_addr.s_addr = route_query->dest_addr.s_addr;
444 rc->route_query.query_id = route_query->query_id;
445 strlcpy(rc->client_addr.sun_path, client_addr.sun_path,
446 sizeof(rc->client_addr.sun_path));
447 rc->client_length = client_length;
448 rc->next = gt->gt_rsrr_cache;
449 gt->gt_rsrr_cache = rc;
450 logit(LOG_DEBUG, 0, "Cached query id %ld from client %s\n",
451 rc->route_query.query_id,rc->client_addr.sun_path);
452 }
453
454 /* Send all the messages in the cache. Currently this is used to send
455 * all the cached Route Reply messages for route change notification.
456 */
457 void
rsrr_cache_send(gt,notify)458 rsrr_cache_send(gt,notify)
459 struct gtable *gt;
460 int notify;
461 {
462 struct rsrr_cache *rc, **rcnp;
463 int flags = 0;
464
465 if (notify)
466 BIT_SET(flags,RSRR_NOTIFICATION_BIT);
467
468 rcnp = >->gt_rsrr_cache;
469 while ((rc = *rcnp) != NULL) {
470 if (rsrr_accept_rq(&rc->route_query,flags,gt) < 0) {
471 logit(LOG_DEBUG, 0, "Deleting cached query id %ld from client %s\n",
472 rc->route_query.query_id,rc->client_addr.sun_path);
473 /* Delete cache entry. */
474 *rcnp = rc->next;
475 free(rc);
476 } else {
477 rcnp = &rc->next;
478 }
479 }
480 }
481
482 /* Clean the cache by deleting all entries. */
483 void
rsrr_cache_clean(gt)484 rsrr_cache_clean(gt)
485 struct gtable *gt;
486 {
487 struct rsrr_cache *rc,*rc_next;
488
489 printf("cleaning cache for group %s\n",
490 inet_fmt(gt->gt_mcastgrp));
491 rc = gt->gt_rsrr_cache;
492 while (rc) {
493 rc_next = rc->next;
494 free(rc);
495 rc = rc_next;
496 }
497 gt->gt_rsrr_cache = NULL;
498 }
499
500 void
rsrr_clean()501 rsrr_clean()
502 {
503 unlink(RSRR_SERV_PATH);
504 }
505
506 #endif /* RSRR */
507