2 * Copyright 2000, International Business Machines Corporation and others.
5 * This software has been released under the terms of the IBM Public
6 * License. For details, see the LICENSE file in the top-level source
7 * directory or online at http://www.openafs.org/dl/license10.html
13 #include <afsconfig.h>
14 #include "../afs/param.h"
18 #include "../afs/stds.h"
19 #include "../afs/sysincludes.h" /* Standard vendor system headers */
23 #include <netinet/in.h>
26 #include "../h/hashing.h"
28 #if !defined(AFS_HPUX110_ENV) && !defined(AFS_LINUX20_ENV)
29 #include <netinet/in_var.h>
30 #endif /* ! ASF_HPUX110_ENV */
31 #endif /* !defined(UKERNEL) */
33 #include "../afs/afsincludes.h" /* Afs-based standard headers */
34 #include "../afs/afs_stats.h" /* afs statistics */
36 #if defined(AFS_SUN56_ENV)
38 #include <inet/common.h>
39 #if defined(AFS_SUN58_ENV)
40 #include <netinet/ip6.h>
45 /* Exported variables */
46 afs_rwlock_t afs_xcell; /* allocation lock for cells */
48 afs_int32 afs_cellindex=0;
49 afs_uint32 afs_nextCellNum = 0x100;
52 /* Local variables. */
53 struct cell *afs_rootcell = 0;
55 /* Handler waiting for request from client */
56 static char afs_AfsdbHandlerWait;
57 /* Client waiting for handler to become available or finish request */
58 static char afs_AfsdbLookupWait;
60 /* Set to 1 when we've seen the userspace AFSDB process at least once */
61 char afs_AfsdbHandlerPresent = 0;
62 /* Set to 1 when there is a client interacting with the AFSDB handler.
63 * Protects the in and out variables below. Protected by GLOCK. */
64 char afs_AfsdbHandlerInuse = 0;
65 /* Set to 1 when AFSDB has been shut down */
66 char afs_AfsdbHandlerShutdown = 0;
68 /* Input to handler from the client: cell name to look up */
69 char *afs_AfsdbHandler_CellName;
70 /* Outputs from handler to client: cell hosts, TTL, and real cell name */
71 afs_int32 *afs_AfsdbHandler_CellHosts;
72 int *afs_AfsdbHandler_Timeout;
73 char **afs_AfsdbHandler_RealName;
75 /* Client sets ReqPending to 1 whenever it queues a request for it */
76 char afs_AfsdbHandler_ReqPending = 0;
77 /* Handler sets Completed to 1 when it completes the client request */
78 char afs_AfsdbHandler_Completed = 0;
81 int afs_strcasecmp(s1, s2)
82 register char *s1, *s2;
89 if (c1 >= 'A' && c1 <= 'Z') c1 += 0x20;
90 if (c2 >= 'A' && c2 <= 'Z') c2 += 0x20;
102 if (afs_AfsdbHandlerPresent) {
103 afs_osi_Wakeup(&afs_AfsdbHandlerWait);
105 afs_AfsdbHandlerShutdown = 1;
106 afs_termState = AFSOP_STOP_RXEVENT;
110 int afs_AfsdbHandler(acellName, acellNameLen, kernelMsg)
113 afs_int32 *kernelMsg;
115 /* afs_syscall_call() has already grabbed the global lock */
117 if (afs_AfsdbHandlerShutdown) return -2;
118 afs_AfsdbHandlerPresent = 1;
120 if (afs_AfsdbHandler_ReqPending) {
123 hostCount = kernelMsg[0];
124 *afs_AfsdbHandler_Timeout = kernelMsg[1];
125 if (*afs_AfsdbHandler_Timeout) *afs_AfsdbHandler_Timeout += osi_Time();
127 *afs_AfsdbHandler_RealName = afs_osi_Alloc(strlen(acellName) + 1);
128 strcpy(*afs_AfsdbHandler_RealName, acellName);
130 for (i=0; i<MAXCELLHOSTS; i++) {
132 afs_AfsdbHandler_CellHosts[i] = 0;
134 afs_AfsdbHandler_CellHosts[i] = kernelMsg[2+i];
137 /* Request completed, wake up the relevant thread */
138 afs_AfsdbHandler_ReqPending = 0;
139 afs_AfsdbHandler_Completed = 1;
140 afs_osi_Wakeup(&afs_AfsdbLookupWait);
143 /* Wait for a request */
144 while (afs_AfsdbHandler_ReqPending == 0 && afs_termState != AFSOP_STOP_AFSDB)
145 afs_osi_Sleep(&afs_AfsdbHandlerWait);
147 /* Check if we're shutting down */
148 if (afs_termState == AFSOP_STOP_AFSDB) {
149 /* Inform anyone waiting for us that we're going away */
150 afs_AfsdbHandlerShutdown = 1;
151 afs_AfsdbHandlerPresent = 0;
152 afs_osi_Wakeup(&afs_AfsdbLookupWait);
154 afs_termState = AFSOP_STOP_RXEVENT;
155 afs_osi_Wakeup(&afs_termState);
159 /* Copy the requested cell name into the request buffer */
160 strncpy(acellName, afs_AfsdbHandler_CellName, acellNameLen);
162 /* Return the lookup request to userspace */
168 int afs_GetCellHostsFromDns(acellName, acellHosts, timeout, realName)
170 afs_int32 *acellHosts;
177 if (!afs_AfsdbHandlerPresent) return ENOENT;
179 /* Initialize host list to empty in case the handler is gone */
182 if (!ISAFS_GLOCK()) {
187 /* Wait until the AFSDB handler is available, and grab it */
188 while (afs_AfsdbHandlerInuse)
189 afs_osi_Sleep(&afs_AfsdbLookupWait);
190 afs_AfsdbHandlerInuse = 1;
192 /* Set up parameters for the handler */
193 afs_AfsdbHandler_CellName = acellName;
194 afs_AfsdbHandler_CellHosts = acellHosts;
195 afs_AfsdbHandler_Timeout = timeout;
196 afs_AfsdbHandler_RealName = realName;
198 /* Wake up the AFSDB handler */
199 afs_AfsdbHandler_Completed = 0;
200 afs_AfsdbHandler_ReqPending = 1;
201 afs_osi_Wakeup(&afs_AfsdbHandlerWait);
203 /* Wait for the handler to get back to us with the reply */
204 while (afs_AfsdbHandlerPresent && !afs_AfsdbHandler_Completed)
205 afs_osi_Sleep(&afs_AfsdbLookupWait);
207 /* Release the AFSDB handler and wake up others waiting for it */
208 afs_AfsdbHandlerInuse = 0;
209 afs_osi_Wakeup(&afs_AfsdbLookupWait);
211 if (grab_glock) AFS_GUNLOCK();
213 if (*acellHosts) return 0;
221 void afs_RefreshCell(ac)
222 register struct cell *ac;
224 afs_int32 cellHosts[MAXCELLHOSTS];
225 char *realName = NULL;
229 if (ac->cellHosts[0]) /* If we already have some servers.. */
230 if (!ac->timeout || ac->timeout > osi_Time())
231 /* Don't refresh if not expired */
234 if (afs_GetCellHostsFromDns(ac->cellName, cellHosts, &timeout, &realName))
235 /* In case of lookup failure, keep old data */
238 /* Refresh the DB servers for the real cell; other values stay the same. */
239 afs_NewCell(realName, cellHosts, 0, (char *) 0, 0, 0, timeout, (char *) 0);
241 /* If this is an alias, update the alias entry too */
242 if (afs_strcasecmp(ac->cellName, realName)) {
244 * Look up the entry we just updated, to compensate for
245 * uppercase-vs-lowercase lossage with DNS.
247 tc = afs_FindCellByName(realName, READ_LOCK);
250 afs_NewCell(ac->cellName, 0, CAlias, (char *) 0, 0, 0,
251 timeout, tc->cellName);
252 afs_PutCell(tc, READ_LOCK);
258 afs_osi_Free(realName, strlen(realName) + 1);
262 struct cell *afs_GetCellByName_Dns(acellName, locktype)
263 register char *acellName;
266 afs_int32 cellHosts[MAXCELLHOSTS];
267 char *realName = NULL;
271 if (afs_GetCellHostsFromDns(acellName, cellHosts, &timeout, &realName))
273 if (afs_NewCell(realName, cellHosts, CNoSUID, (char *) 0, 0, 0,
274 timeout, (char *) 0))
277 /* If this is an alias, create an entry for it too */
278 if (afs_strcasecmp(acellName, realName)) {
280 * Look up the entry we just updated, to compensate for
281 * uppercase-vs-lowercase lossage with DNS.
283 tc = afs_FindCellByName(realName, READ_LOCK);
287 if (afs_NewCell(acellName, 0, CAlias, (char *) 0, 0, 0,
288 timeout, tc->cellName)) {
289 afs_PutCell(tc, READ_LOCK);
293 afs_PutCell(tc, READ_LOCK);
297 afs_osi_Free(realName, strlen(realName) + 1);
298 return afs_FindCellByName(acellName, locktype);
302 afs_osi_Free(realName, strlen(realName) + 1);
303 return (struct cell *) 0;
307 struct cell *afs_FindCellByName(acellName, locktype)
308 register char *acellName;
311 register struct cell *tc;
312 register struct afs_q *cq, *tq;
315 AFS_STATCNT(afs_GetCellByName);
317 ObtainWriteLock(&afs_xcell,100);
318 for (cq = CellLRU.next; cq != &CellLRU; cq = tq) {
319 tc = QTOC(cq); tq = QNext(cq);
320 if (!afs_strcasecmp(tc->cellName, acellName)) {
322 QAdd(&CellLRU, &tc->lruq);
323 ReleaseWriteLock(&afs_xcell);
325 if ((tc->states & CAlias) && (didAlias == 0)) {
326 acellName = tc->realName;
327 if (!acellName) return (struct cell *) 0;
335 ReleaseWriteLock(&afs_xcell);
336 return (struct cell *) 0;
337 } /*afs_FindCellByName*/
340 struct cell *afs_GetCellByName(acellName, locktype)
341 register char *acellName;
346 tc = afs_FindCellByName(acellName, locktype);
348 tc = afs_GetCellByName_Dns(acellName, locktype);
351 } /*afs_GetCellByName*/
353 static struct cell *afs_GetCellInternal(acell, locktype, holdxcell)
354 register afs_int32 acell;
358 register struct cell *tc;
359 register struct afs_q *cq, *tq;
361 AFS_STATCNT(afs_GetCell);
362 if (acell == 1 && afs_rootcell) return afs_rootcell;
364 ObtainWriteLock(&afs_xcell,101);
365 for (cq = CellLRU.next; cq != &CellLRU; cq = tq) {
366 tc = QTOC(cq); tq = QNext(cq);
367 if (tc->cell == acell) {
369 QAdd(&CellLRU, &tc->lruq);
371 ReleaseWriteLock(&afs_xcell);
377 ReleaseWriteLock(&afs_xcell);
378 return (struct cell *) 0;
382 struct cell *afs_GetCell(acell, locktype)
383 register afs_int32 acell;
386 return afs_GetCellInternal(acell, locktype, 1);
389 /* This is only to be called if the caller is already holding afs_xcell */
390 struct cell *afs_GetCellNoLock(acell, locktype)
391 register afs_int32 acell;
394 return afs_GetCellInternal(acell, locktype, 0);
397 struct cell *afs_GetCellByIndex(cellindex, locktype, refresh)
398 register afs_int32 cellindex;
402 register struct cell *tc;
403 register struct afs_q *cq, *tq;
405 AFS_STATCNT(afs_GetCellByIndex);
406 ObtainWriteLock(&afs_xcell,102);
407 for (cq = CellLRU.next; cq != &CellLRU; cq = tq) {
408 tc = QTOC(cq); tq = QNext(cq);
409 if (tc->cellIndex == cellindex) {
411 QAdd(&CellLRU, &tc->lruq);
412 ReleaseWriteLock(&afs_xcell);
413 if (refresh) afs_RefreshCell(tc);
417 ReleaseWriteLock(&afs_xcell);
418 return (struct cell *) 0;
420 } /*afs_GetCellByIndex*/
423 afs_int32 afs_NewCell(acellName, acellHosts, aflags, linkedcname, fsport, vlport, timeout, aliasFor)
426 register afs_int32 *acellHosts;
428 u_short fsport, vlport;
432 register struct cell *tc, *tcl=0;
433 register afs_int32 i, newc=0, code=0;
434 register struct afs_q *cq, *tq;
436 AFS_STATCNT(afs_NewCell);
438 ObtainWriteLock(&afs_xcell,103);
440 /* Find the cell and mark its servers as not down but gone */
441 for (cq = CellLRU.next; cq != &CellLRU; cq = tq) {
442 tc = QTOC(cq); tq = QNext(cq);
443 if (afs_strcasecmp(tc->cellName, acellName) == 0) {
444 /* If the cell we've found has the correct name but no timeout,
445 * and we're called with a non-zero timeout, bail out: never
446 * override static configuration entries with AFSDB ones.
447 * One exception: if the original cell entry had no servers,
448 * it must get servers from AFSDB.
450 if (timeout && !tc->timeout && tc->cellHosts[0]) {
451 ReleaseWriteLock(&afs_xcell);
454 /* we don't want to keep pinging old vlservers which were down,
455 * since they don't matter any more. It's easier to do this than
456 * to remove the server from its various hash tables. */
457 for (i=0; i<MAXCELLHOSTS; i++) {
458 if (!tc->cellHosts[i]) break;
459 tc->cellHosts[i]->flags &= ~SRVR_ISDOWN;
460 tc->cellHosts[i]->flags |= SRVR_ISGONE;
466 if (cq != &CellLRU) {
470 tc = (struct cell *) afs_osi_Alloc(sizeof(struct cell));
471 memset((char *)tc, 0, sizeof(*tc));
472 QAdd(&CellLRU, &tc->lruq); /* put in lruq */
473 tc->cellName = (char *) afs_osi_Alloc(strlen(acellName)+1);
474 strcpy(tc->cellName, acellName);
475 tc->cellIndex = afs_cellindex++;
476 if (aflags & CPrimary) {
477 extern int afs_rootCellIndex;
478 tc->cell = 1; /* primary cell is always 1 */
480 afs_rootCellIndex = tc->cellIndex;
482 tc->cell = afs_nextCellNum++;
485 tc->lcellp = (struct cell *)0;
486 tc->fsport = (fsport ? fsport : AFS_FSPORT);
487 tc->vlport = (vlport ? vlport : AFS_VLPORT);
488 afs_stats_cmperf.numCellsVisible++;
492 if (aflags & CLinkedCell) {
497 for (cq = CellLRU.next; cq != &CellLRU; cq = tq) {
498 tcl = QTOC(cq); tq = QNext(cq);
499 if (!afs_strcasecmp(tcl->cellName, linkedcname)) {
508 if (tcl->lcellp) { /* XXX Overwriting if one existed before! XXX */
509 tcl->lcellp->lcellp = (struct cell *)0;
510 tcl->lcellp->states &= ~CLinkedCell;
515 tc->states |= aflags;
516 tc->timeout = timeout;
518 /* Allow converting an alias into a real cell */
519 if (!(aflags & CAlias)) tc->states &= ~CAlias;
521 memset((char *)tc->cellHosts, 0, sizeof(tc->cellHosts));
522 if (aflags & CAlias) {
527 if (tc->realName) afs_osi_Free(tc->realName, strlen(tc->realName)+1);
528 tc->realName = (char *) afs_osi_Alloc(strlen(aliasFor)+1);
529 strcpy(tc->realName, aliasFor);
533 for (i=0; i<MAXCELLHOSTS; i++) {
535 afs_uint32 temp = acellHosts[i];
537 ts = afs_GetServer(&temp, 1, 0, tc->vlport, WRITE_LOCK, (afsUUID *)0, 0);
539 ts->flags &= ~SRVR_ISGONE;
540 tc->cellHosts[i] = ts;
541 afs_PutServer(ts, WRITE_LOCK);
543 afs_SortServers(tc->cellHosts, MAXCELLHOSTS); /* randomize servers */
545 ReleaseWriteLock(&afs_xcell);
550 afs_osi_Free(tc->cellName, strlen(tc->cellName)+1);
551 afs_osi_Free((char *)tc, sizeof(struct cell));
553 ReleaseWriteLock(&afs_xcell);
558 afs_RemoveCellEntry(struct server *srvp)
566 /* Remove the server structure from the cell list - if there */
567 ObtainWriteLock(&afs_xcell,200);
568 for (j=k=0; j<MAXCELLHOSTS; j++) {
569 if (!tc->cellHosts[j]) break;
570 if (tc->cellHosts[j] != srvp) {
571 tc->cellHosts[k++] = tc->cellHosts[j];
575 /* What do we do if we remove the last one? */
577 for (; k<MAXCELLHOSTS; k++) {
578 tc->cellHosts[k] = 0;
580 ReleaseWriteLock(&afs_xcell);