| 1 | /* |
| 2 | * Copyright (c) 1986, 1988 Regents of the University of California. |
| 3 | * 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 | * 3. All advertising materials mentioning features or use of this software |
| 14 | * must display the following acknowledgement: |
| 15 | * This product includes software developed by the University of |
| 16 | * California, Berkeley and its contributors. |
| 17 | * 4. Neither the name of the University nor the names of its contributors |
| 18 | * may be used to endorse or promote products derived from this software |
| 19 | * without specific prior written permission. |
| 20 | * |
| 21 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
| 22 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 23 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 24 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
| 25 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 26 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 27 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 28 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 29 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 30 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 31 | * SUCH DAMAGE. |
| 32 | */ |
| 33 | |
| 34 | #ifndef lint |
| 35 | static char sccsid[] = "@(#)ns_maint.c 4.39 (Berkeley) 3/2/91"; |
| 36 | #endif /* not lint */ |
| 37 | |
| 38 | #include <sys/param.h> |
| 39 | #include <sys/socket.h> |
| 40 | #include <sys/time.h> |
| 41 | #if defined(SYSV) |
| 42 | #include <unistd.h> |
| 43 | #endif SYSV |
| 44 | #include <netinet/in.h> |
| 45 | #include <stdio.h> |
| 46 | #include <syslog.h> |
| 47 | #include <signal.h> |
| 48 | #include <errno.h> |
| 49 | #include <arpa/nameser.h> |
| 50 | #include <sys/wait.h> |
| 51 | #include "ns.h" |
| 52 | #include "db.h" |
| 53 | #include "pathnames.h" |
| 54 | |
| 55 | extern int errno; |
| 56 | extern int maint_interval; |
| 57 | extern int needzoneload; |
| 58 | extern u_short ns_port; |
| 59 | extern char *ctime(); |
| 60 | |
| 61 | int xfers_running; /* number of xfers running */ |
| 62 | int xfers_deferred; /* number of needed xfers not run yet */ |
| 63 | static int alarm_pending; |
| 64 | |
| 65 | |
| 66 | /* |
| 67 | * Invoked at regular intervals by signal interrupt; refresh all secondary |
| 68 | * zones from primary name server and remove old cache entries. Also, |
| 69 | * ifdef'd ALLOW_UPDATES, dump database if it has changed since last |
| 70 | * dump/bootup. |
| 71 | */ |
| 72 | ns_maint() |
| 73 | { |
| 74 | register struct zoneinfo *zp; |
| 75 | struct itimerval ival; |
| 76 | time_t next_refresh = 0; |
| 77 | int zonenum; |
| 78 | |
| 79 | gettime(&tt); |
| 80 | |
| 81 | #ifdef DEBUG |
| 82 | if (debug) |
| 83 | fprintf(ddt,"\nns_maint(); now %s", ctime(&tt.tv_sec)); |
| 84 | #endif |
| 85 | |
| 86 | xfers_deferred = 0; |
| 87 | alarm_pending = 0; |
| 88 | for (zp = zones, zonenum = 0; zp < &zones[nzones]; zp++, zonenum++) { |
| 89 | #ifdef DEBUG |
| 90 | if (debug >= 2) |
| 91 | printzoneinfo(zonenum); |
| 92 | #endif |
| 93 | if (tt.tv_sec >= zp->z_time && zp->z_refresh > 0) { |
| 94 | /* |
| 95 | * Set default time for next action first, |
| 96 | * so that it can be changed later if necessary. |
| 97 | */ |
| 98 | zp->z_time = tt.tv_sec + zp->z_refresh; |
| 99 | |
| 100 | switch (zp->z_type) { |
| 101 | |
| 102 | case Z_CACHE: |
| 103 | doachkpt(); |
| 104 | break; |
| 105 | |
| 106 | case Z_SECONDARY: |
| 107 | if ((zp->z_state & Z_NEED_RELOAD) == 0) { |
| 108 | if (zp->z_state & Z_XFER_RUNNING) |
| 109 | abortxfer(zp); |
| 110 | else if (xfers_running < MAX_XFERS_RUNNING) |
| 111 | startxfer(zp); |
| 112 | else { |
| 113 | zp->z_state |= Z_NEED_XFER; |
| 114 | ++xfers_deferred; |
| 115 | #ifdef DEBUG |
| 116 | if (debug > 1) |
| 117 | fprintf(ddt, |
| 118 | "xfer deferred for %s\n", |
| 119 | zp->z_origin); |
| 120 | #endif |
| 121 | } |
| 122 | } |
| 123 | break; |
| 124 | #ifdef ALLOW_UPDATES |
| 125 | case Z_PRIMARY: |
| 126 | /* |
| 127 | * Checkpoint the zone if it has changed |
| 128 | * since we last checkpointed |
| 129 | */ |
| 130 | if (zp->hasChanged) |
| 131 | zonedump(zp); |
| 132 | break; |
| 133 | #endif ALLOW_UPDATES |
| 134 | } |
| 135 | gettime(&tt); |
| 136 | } |
| 137 | } |
| 138 | sched_maint(); |
| 139 | #ifdef DEBUG |
| 140 | if (debug) |
| 141 | fprintf(ddt,"exit ns_maint()\n"); |
| 142 | #endif |
| 143 | } |
| 144 | |
| 145 | /* |
| 146 | * Find when the next refresh needs to be and set |
| 147 | * interrupt time accordingly. |
| 148 | */ |
| 149 | sched_maint() |
| 150 | { |
| 151 | register struct zoneinfo *zp; |
| 152 | struct itimerval ival; |
| 153 | time_t next_refresh = 0; |
| 154 | static time_t next_alarm; |
| 155 | |
| 156 | for (zp = zones; zp < &zones[nzones]; zp++) |
| 157 | if (zp->z_time != 0 && |
| 158 | (next_refresh == 0 || next_refresh > zp->z_time)) |
| 159 | next_refresh = zp->z_time; |
| 160 | /* |
| 161 | * Schedule the next call to ns_maint. |
| 162 | * Don't visit any sooner than maint_interval. |
| 163 | */ |
| 164 | bzero((char *)&ival, sizeof (ival)); |
| 165 | if (next_refresh != 0) { |
| 166 | if (next_refresh == next_alarm && alarm_pending) { |
| 167 | #ifdef DEBUG |
| 168 | if (debug) |
| 169 | fprintf(ddt,"sched_maint: no schedule change\n"); |
| 170 | #endif |
| 171 | return; |
| 172 | } |
| 173 | ival.it_value.tv_sec = next_refresh - tt.tv_sec; |
| 174 | if (ival.it_value.tv_sec < maint_interval) |
| 175 | ival.it_value.tv_sec = maint_interval; |
| 176 | next_alarm = next_refresh; |
| 177 | alarm_pending = 1; |
| 178 | } |
| 179 | (void) setitimer(ITIMER_REAL, &ival, (struct itimerval *)NULL); |
| 180 | #ifdef DEBUG |
| 181 | if (debug) |
| 182 | fprintf(ddt,"sched_maint: Next interrupt in %d sec\n", |
| 183 | ival.it_value.tv_sec); |
| 184 | #endif |
| 185 | } |
| 186 | |
| 187 | /* |
| 188 | * Start an asynchronous zone transfer for a zone. |
| 189 | * Depends on current time being in tt. |
| 190 | * The caller must call sched_maint after startxfer. |
| 191 | */ |
| 192 | startxfer(zp) |
| 193 | struct zoneinfo *zp; |
| 194 | { |
| 195 | static char *argv[NSMAX + 20], argv_ns[NSMAX][MAXDNAME]; |
| 196 | int cnt, argc = 0, argc_ns = 0, pid, omask; |
| 197 | char debug_str[10]; |
| 198 | char serial_str[10]; |
| 199 | char port_str[10]; |
| 200 | |
| 201 | #ifdef DEBUG |
| 202 | if (debug) |
| 203 | fprintf(ddt,"startxfer() %s\n", zp->z_origin); |
| 204 | #endif |
| 205 | |
| 206 | argv[argc++] = "named-xfer"; |
| 207 | argv[argc++] = "-z"; |
| 208 | argv[argc++] = zp->z_origin; |
| 209 | argv[argc++] = "-f"; |
| 210 | argv[argc++] = zp->z_source; |
| 211 | argv[argc++] = "-s"; |
| 212 | sprintf(serial_str, "%d", zp->z_serial); |
| 213 | argv[argc++] = serial_str; |
| 214 | if (zp->z_state & Z_SYSLOGGED) |
| 215 | argv[argc++] = "-q"; |
| 216 | argv[argc++] = "-P"; |
| 217 | sprintf(port_str, "%d", ns_port); |
| 218 | argv[argc++] = port_str; |
| 219 | #ifdef DEBUG |
| 220 | if (debug) { |
| 221 | argv[argc++] = "-d"; |
| 222 | sprintf(debug_str, "%d", debug); |
| 223 | argv[argc++] = debug_str; |
| 224 | argv[argc++] = "-l"; |
| 225 | argv[argc++] = "/usr/tmp/xfer.ddt"; |
| 226 | if (debug > 5) { |
| 227 | argv[argc++] = "-t"; |
| 228 | argv[argc++] = "/usr/tmp/xfer.trace"; |
| 229 | } |
| 230 | } |
| 231 | #endif |
| 232 | |
| 233 | /* |
| 234 | * Copy the server ip addresses into argv, after converting |
| 235 | * to ascii and saving the static inet_ntoa result |
| 236 | */ |
| 237 | for (cnt = 0; cnt < zp->z_addrcnt; cnt++) |
| 238 | argv[argc++] = strcpy(argv_ns[argc_ns++], |
| 239 | inet_ntoa(zp->z_addr[cnt])); |
| 240 | |
| 241 | argv[argc] = 0; |
| 242 | |
| 243 | #ifdef DEBUG |
| 244 | #ifdef ECHOARGS |
| 245 | if (debug) { |
| 246 | int i; |
| 247 | for (i = 0; i < argc; i++) |
| 248 | fprintf(ddt, "Arg %d=%s\n", i, argv[i]); |
| 249 | } |
| 250 | #endif /* ECHOARGS */ |
| 251 | #endif /* DEBUG */ |
| 252 | |
| 253 | #ifdef SYSV |
| 254 | #define vfork fork |
| 255 | #else |
| 256 | gettime(&tt); |
| 257 | omask = sigblock(sigmask(SIGCHLD)); |
| 258 | #endif |
| 259 | if ((pid = vfork()) == -1) { |
| 260 | #ifdef DEBUG |
| 261 | if (debug) |
| 262 | fprintf(ddt, "xfer [v]fork: %d\n", errno); |
| 263 | #endif |
| 264 | syslog(LOG_ERR, "xfer [v]fork: %m"); |
| 265 | #ifndef SYSV |
| 266 | (void) sigsetmask(omask); |
| 267 | #endif |
| 268 | zp->z_time = tt.tv_sec + 10; |
| 269 | return; |
| 270 | } |
| 271 | |
| 272 | if (pid) { |
| 273 | #ifdef DEBUG |
| 274 | if (debug) |
| 275 | fprintf(ddt, "started xfer child %d\n", pid); |
| 276 | #endif |
| 277 | zp->z_state &= ~Z_NEED_XFER; |
| 278 | zp->z_state |= Z_XFER_RUNNING; |
| 279 | zp->z_xferpid = pid; |
| 280 | xfers_running++; |
| 281 | zp->z_time = tt.tv_sec + MAX_XFER_TIME; |
| 282 | #ifndef SYSV |
| 283 | (void) sigsetmask(omask); |
| 284 | #endif |
| 285 | } else { |
| 286 | execve(_PATH_XFER, argv, NULL); |
| 287 | syslog(LOG_ERR, "can't exec %s: %m", _PATH_XFER); |
| 288 | _exit(XFER_FAIL); /* avoid duplicate buffer flushes */ |
| 289 | } |
| 290 | } |
| 291 | |
| 292 | #ifdef DEBUG |
| 293 | printzoneinfo(zonenum) |
| 294 | int zonenum; |
| 295 | { |
| 296 | struct timeval tt; |
| 297 | struct zoneinfo *zp = &zones[zonenum]; |
| 298 | char *ZoneType; |
| 299 | |
| 300 | if (!debug) |
| 301 | return; /* Else fprintf to ddt will bomb */ |
| 302 | fprintf(ddt, "printzoneinfo(%d):\n", zonenum); |
| 303 | |
| 304 | gettime(&tt); |
| 305 | switch (zp->z_type) { |
| 306 | case Z_PRIMARY: ZoneType = "Primary"; break; |
| 307 | case Z_SECONDARY: ZoneType = "Secondary"; break; |
| 308 | case Z_CACHE: ZoneType = "Cache"; break; |
| 309 | default: ZoneType = "Unknown"; |
| 310 | } |
| 311 | if (zp->z_origin[0] == '\0') |
| 312 | fprintf(ddt,"origin ='.'"); |
| 313 | else |
| 314 | fprintf(ddt,"origin ='%s'", zp->z_origin); |
| 315 | fprintf(ddt,", type = %s", ZoneType); |
| 316 | fprintf(ddt,", source = %s\n", zp->z_source); |
| 317 | fprintf(ddt,"z_refresh = %ld", zp->z_refresh); |
| 318 | fprintf(ddt,", retry = %ld", zp->z_retry); |
| 319 | fprintf(ddt,", expire = %ld", zp->z_expire); |
| 320 | fprintf(ddt,", minimum = %ld", zp->z_minimum); |
| 321 | fprintf(ddt,", serial = %ld\n", zp->z_serial); |
| 322 | fprintf(ddt,"z_time = %d", zp->z_time); |
| 323 | if (zp->z_time) { |
| 324 | fprintf(ddt,", now time : %d sec", tt.tv_sec); |
| 325 | fprintf(ddt,", time left: %d sec", zp->z_time - tt.tv_sec); |
| 326 | } |
| 327 | fprintf(ddt,"; state %x\n", zp->z_state); |
| 328 | } |
| 329 | #endif DEBUG |
| 330 | |
| 331 | /* |
| 332 | * remove_zone (htp, zone) -- |
| 333 | * Delete all RR's in the zone "zone" under specified hash table. |
| 334 | */ |
| 335 | remove_zone(htp, zone) |
| 336 | register struct hashbuf *htp; |
| 337 | register int zone; |
| 338 | { |
| 339 | register struct databuf *dp, *pdp; |
| 340 | register struct namebuf *np; |
| 341 | struct namebuf **npp, **nppend; |
| 342 | |
| 343 | nppend = htp->h_tab + htp->h_size; |
| 344 | for (npp = htp->h_tab; npp < nppend; npp++) |
| 345 | for (np = *npp; np != NULL; np = np->n_next) { |
| 346 | for (pdp = NULL, dp = np->n_data; dp != NULL; ) { |
| 347 | if (dp->d_zone == zone) |
| 348 | dp = rm_datum(dp, np, pdp); |
| 349 | else { |
| 350 | pdp = dp; |
| 351 | dp = dp->d_next; |
| 352 | } |
| 353 | } |
| 354 | /* Call recursively to remove subdomains. */ |
| 355 | if (np->n_hash) |
| 356 | remove_zone(np->n_hash, zone); |
| 357 | } |
| 358 | } |
| 359 | |
| 360 | /* |
| 361 | * Abort an xfer that has taken too long. |
| 362 | */ |
| 363 | abortxfer(zp) |
| 364 | register struct zoneinfo *zp; |
| 365 | { |
| 366 | |
| 367 | kill(zp->z_xferpid, SIGKILL); /* don't trust it at all */ |
| 368 | #ifdef DEBUG |
| 369 | if (debug) |
| 370 | fprintf(ddt, "Killed child %d (zone %s) due to timeout\n", |
| 371 | zp->z_xferpid, zp->z_origin); |
| 372 | #endif /* DEBUG */ |
| 373 | zp->z_time = tt.tv_sec + zp->z_retry; |
| 374 | } |
| 375 | |
| 376 | #ifdef SYSV |
| 377 | union wait { |
| 378 | unsigned short w_termsig:7; /* termination signal */ |
| 379 | unsigned short w_coredump:1; /* core dump indicator */ |
| 380 | unsigned short w_retcode:8; /* exit code if w_termsig==0 */ |
| 381 | }; |
| 382 | #endif |
| 383 | |
| 384 | /* |
| 385 | * SIGCHLD signal handler: process exit of xfer's. |
| 386 | * (Note: also called when outgoing transfer completes.) |
| 387 | */ |
| 388 | SIG_FN |
| 389 | endxfer() |
| 390 | { |
| 391 | register struct zoneinfo *zp; |
| 392 | int pid, xfers = 0; |
| 393 | union wait status; |
| 394 | |
| 395 | gettime(&tt); |
| 396 | #if defined(SYSV) |
| 397 | { int stat; |
| 398 | pid = wait(&stat); |
| 399 | status.w_termsig = stat & 0x7f; |
| 400 | status.w_retcode = stat >> 8; |
| 401 | } |
| 402 | #else /* SYSV */ |
| 403 | while ((pid = |
| 404 | wait3((int *)&status, WNOHANG, (struct rusage *)NULL)) > 0) { |
| 405 | #endif /* SYSV */ |
| 406 | for (zp = zones; zp < &zones[nzones]; zp++) |
| 407 | if (zp->z_xferpid == pid) { |
| 408 | xfers++; |
| 409 | xfers_running--; |
| 410 | zp->z_xferpid = 0; |
| 411 | zp->z_state &= ~Z_XFER_RUNNING; |
| 412 | #ifdef DEBUG |
| 413 | if (debug) |
| 414 | fprintf(ddt, |
| 415 | "\nendxfer: child %d zone %s returned status=%d termsig=%d\n", |
| 416 | pid, zp->z_origin, status.w_retcode, |
| 417 | status.w_termsig); |
| 418 | #endif |
| 419 | if (status.w_termsig != 0) { |
| 420 | if (status.w_termsig != SIGKILL) { |
| 421 | syslog(LOG_ERR, |
| 422 | "named-xfer exited with signal %d\n", |
| 423 | status.w_termsig); |
| 424 | #ifdef DEBUG |
| 425 | if (debug) |
| 426 | fprintf(ddt, |
| 427 | "\tchild termination with signal %d\n", |
| 428 | status.w_termsig); |
| 429 | #endif |
| 430 | } |
| 431 | zp->z_time = tt.tv_sec + zp->z_retry; |
| 432 | } else switch (status.w_retcode) { |
| 433 | case XFER_UPTODATE: |
| 434 | zp->z_state &= ~Z_SYSLOGGED; |
| 435 | zp->z_lastupdate = tt.tv_sec; |
| 436 | zp->z_time = tt.tv_sec + zp->z_refresh; |
| 437 | /* |
| 438 | * Restore z_auth in case expired, |
| 439 | * but only if there were no errors |
| 440 | * in the zone file. |
| 441 | */ |
| 442 | if ((zp->z_state & Z_DB_BAD) == 0) |
| 443 | zp->z_auth = 1; |
| 444 | if (zp->z_source) { |
| 445 | #if defined(SYSV) |
| 446 | struct utimbuf t; |
| 447 | |
| 448 | t.actime = tt.tv_sec; |
| 449 | t.modtime = tt.tv_sec; |
| 450 | (void) utime(zp->z_source, &t); |
| 451 | #else |
| 452 | struct timeval t[2]; |
| 453 | |
| 454 | t[0] = tt; |
| 455 | t[1] = tt; |
| 456 | (void) utimes(zp->z_source, t); |
| 457 | #endif /* SYSV */ |
| 458 | } |
| 459 | break; |
| 460 | |
| 461 | case XFER_SUCCESS: |
| 462 | zp->z_state |= Z_NEED_RELOAD; |
| 463 | zp->z_state &= ~Z_SYSLOGGED; |
| 464 | needzoneload++; |
| 465 | break; |
| 466 | |
| 467 | case XFER_TIMEOUT: |
| 468 | #ifdef DEBUG |
| 469 | if (debug) fprintf(ddt, |
| 470 | "zoneref: Masters for secondary zone %s unreachable\n", |
| 471 | zp->z_origin); |
| 472 | #endif |
| 473 | if ((zp->z_state & Z_SYSLOGGED) == 0) { |
| 474 | zp->z_state |= Z_SYSLOGGED; |
| 475 | syslog(LOG_WARNING, |
| 476 | "zoneref: Masters for secondary zone %s unreachable", |
| 477 | zp->z_origin); |
| 478 | } |
| 479 | zp->z_time = tt.tv_sec + zp->z_retry; |
| 480 | break; |
| 481 | |
| 482 | default: |
| 483 | if ((zp->z_state & Z_SYSLOGGED) == 0) { |
| 484 | zp->z_state |= Z_SYSLOGGED; |
| 485 | syslog(LOG_ERR, |
| 486 | "named-xfer exit code %d", |
| 487 | status.w_retcode); |
| 488 | } |
| 489 | /* FALLTHROUGH */ |
| 490 | case XFER_FAIL: |
| 491 | zp->z_state |= Z_SYSLOGGED; |
| 492 | zp->z_time = tt.tv_sec + zp->z_retry; |
| 493 | break; |
| 494 | } |
| 495 | break; |
| 496 | } |
| 497 | #ifndef SYSV |
| 498 | } |
| 499 | #endif /* SYSV */ |
| 500 | if (xfers) { |
| 501 | for (zp = zones; |
| 502 | xfers_deferred != 0 && xfers_running < MAX_XFERS_RUNNING && |
| 503 | zp < &zones[nzones]; zp++) |
| 504 | if (zp->z_state & Z_NEED_XFER) { |
| 505 | xfers_deferred--; |
| 506 | startxfer(zp); |
| 507 | } |
| 508 | sched_maint(); |
| 509 | } |
| 510 | #if defined(SYSV) |
| 511 | (void)signal(SIGCLD, endxfer); |
| 512 | #endif |
| 513 | } |
| 514 | |
| 515 | /* |
| 516 | * Reload zones whose transfers have completed. |
| 517 | */ |
| 518 | loadxfer() |
| 519 | { |
| 520 | register struct zoneinfo *zp; |
| 521 | |
| 522 | gettime(&tt); |
| 523 | for (zp = zones; zp < &zones[nzones]; zp++) |
| 524 | if (zp->z_state & Z_NEED_RELOAD) { |
| 525 | #ifdef DEBUG |
| 526 | if (debug) |
| 527 | fprintf(ddt, "loadxfer() '%s'\n", |
| 528 | zp->z_origin[0] ? zp->z_origin : "."); |
| 529 | #endif |
| 530 | zp->z_state &= ~Z_NEED_RELOAD; |
| 531 | zp->z_auth = 0; |
| 532 | remove_zone(hashtab, zp - zones); |
| 533 | if (db_load(zp->z_source, zp->z_origin, zp, 0) == 0) |
| 534 | zp->z_auth = 1; |
| 535 | if (zp->z_state & Z_TMP_FILE) |
| 536 | (void) unlink(zp->z_source); |
| 537 | } |
| 538 | sched_maint(); |
| 539 | } |