1 /* 2 * xfrd-disk.c - XFR (transfer) Daemon TCP system source file. Read/Write state to disk. 3 * 4 * Copyright (c) 2001-2006, NLnet Labs. All rights reserved. 5 * 6 * See LICENSE for the license. 7 * 8 */ 9 10 #include "config.h" 11 #include <stdio.h> 12 #include <stdlib.h> 13 #include <ctype.h> 14 #include <errno.h> 15 #include <sys/stat.h> 16 #include <sys/types.h> 17 #include <unistd.h> 18 #include "xfrd-disk.h" 19 #include "xfrd.h" 20 #include "buffer.h" 21 #include "nsd.h" 22 #include "options.h" 23 24 /* quick tokenizer, reads words separated by whitespace. 25 No quoted strings. Comments are skipped (#... eol). */ 26 static char* 27 xfrd_read_token(FILE* in) 28 { 29 static char buf[4000]; 30 buf[sizeof(buf)-1]=0; 31 while(1) { 32 if(fscanf(in, " %3990s", buf) != 1) 33 return 0; 34 35 if(buf[0] != '#') 36 return buf; 37 38 if(!fgets(buf, sizeof(buf), in)) 39 return 0; 40 } 41 } 42 43 static int 44 xfrd_read_i16(FILE *in, uint16_t* v) 45 { 46 char* p = xfrd_read_token(in); 47 if(!p) 48 return 0; 49 50 *v=atoi(p); 51 return 1; 52 } 53 54 static int 55 xfrd_read_i32(FILE *in, uint32_t* v) 56 { 57 char* p = xfrd_read_token(in); 58 if(!p) 59 return 0; 60 61 *v=atoi(p); 62 return 1; 63 } 64 65 static int 66 xfrd_read_time_t(FILE *in, time_t* v) 67 { 68 char* p = xfrd_read_token(in); 69 if(!p) 70 return 0; 71 72 *v=atol(p); 73 return 1; 74 } 75 76 static int 77 xfrd_read_check_str(FILE* in, const char* str) 78 { 79 char *p = xfrd_read_token(in); 80 if(!p) 81 return 0; 82 83 if(strcmp(p, str) != 0) 84 return 0; 85 86 return 1; 87 } 88 89 static int 90 xfrd_read_state_soa(FILE* in, const char* id_acquired, 91 const char* id, xfrd_soa_type* soa, time_t* soatime) 92 { 93 char *p; 94 95 if(!xfrd_read_check_str(in, id_acquired) || 96 !xfrd_read_time_t(in, soatime)) { 97 return 0; 98 } 99 100 if(*soatime == 0) 101 return 1; 102 103 if(!xfrd_read_check_str(in, id) || 104 !xfrd_read_i16(in, &soa->type) || 105 !xfrd_read_i16(in, &soa->klass) || 106 !xfrd_read_i32(in, &soa->ttl) || 107 !xfrd_read_i16(in, &soa->rdata_count)) 108 { 109 return 0; 110 } 111 112 soa->type = htons(soa->type); 113 soa->klass = htons(soa->klass); 114 soa->ttl = htonl(soa->ttl); 115 soa->rdata_count = htons(soa->rdata_count); 116 117 if(!(p=xfrd_read_token(in)) || 118 !(soa->prim_ns[0] = dname_parse_wire(soa->prim_ns+1, p))) 119 return 0; 120 121 if(!(p=xfrd_read_token(in)) || 122 !(soa->email[0] = dname_parse_wire(soa->email+1, p))) 123 return 0; 124 125 if(!xfrd_read_i32(in, &soa->serial) || 126 !xfrd_read_i32(in, &soa->refresh) || 127 !xfrd_read_i32(in, &soa->retry) || 128 !xfrd_read_i32(in, &soa->expire) || 129 !xfrd_read_i32(in, &soa->minimum)) 130 { 131 return 0; 132 } 133 134 soa->serial = htonl(soa->serial); 135 soa->refresh = htonl(soa->refresh); 136 soa->retry = htonl(soa->retry); 137 soa->expire = htonl(soa->expire); 138 soa->minimum = htonl(soa->minimum); 139 return 1; 140 } 141 142 void 143 xfrd_read_state(struct xfrd_state* xfrd) 144 { 145 const char* statefile = xfrd->nsd->options->xfrdfile; 146 FILE *in; 147 uint32_t filetime = 0; 148 uint32_t numzones, i; 149 region_type *tempregion; 150 time_t soa_refresh; 151 152 tempregion = region_create(xalloc, free); 153 if(!tempregion) 154 return; 155 156 in = fopen(statefile, "r"); 157 if(!in) { 158 if(errno != ENOENT) { 159 log_msg(LOG_ERR, "xfrd: Could not open file %s for reading: %s", 160 statefile, strerror(errno)); 161 } else { 162 DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: no file %s. refreshing all zones.", 163 statefile)); 164 } 165 region_destroy(tempregion); 166 return; 167 } 168 if(!xfrd_read_check_str(in, XFRD_FILE_MAGIC)) { 169 /* older file version; reset everything */ 170 DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: file %s is old version. refreshing all zones.", 171 statefile)); 172 fclose(in); 173 region_destroy(tempregion); 174 return; 175 } 176 if(!xfrd_read_check_str(in, "filetime:") || 177 !xfrd_read_i32(in, &filetime) || 178 (time_t)filetime > xfrd_time()+15 || 179 !xfrd_read_check_str(in, "numzones:") || 180 !xfrd_read_i32(in, &numzones)) 181 { 182 log_msg(LOG_ERR, "xfrd: corrupt state file %s dated %d (now=%lld)", 183 statefile, (int)filetime, (long long)xfrd_time()); 184 fclose(in); 185 region_destroy(tempregion); 186 return; 187 } 188 189 for(i=0; i<numzones; i++) { 190 char *p; 191 xfrd_zone_type* zone; 192 const dname_type* dname; 193 uint32_t state, masnum, nextmas, round_num, timeout, backoff; 194 xfrd_soa_type soa_nsd_read, soa_disk_read, soa_notified_read; 195 time_t soa_nsd_acquired_read, 196 soa_disk_acquired_read, soa_notified_acquired_read; 197 xfrd_soa_type incoming_soa; 198 time_t incoming_acquired; 199 200 if(nsd.signal_hint_shutdown) { 201 fclose(in); 202 region_destroy(tempregion); 203 return; 204 } 205 206 memset(&soa_nsd_read, 0, sizeof(soa_nsd_read)); 207 memset(&soa_disk_read, 0, sizeof(soa_disk_read)); 208 memset(&soa_notified_read, 0, sizeof(soa_notified_read)); 209 210 if(!xfrd_read_check_str(in, "zone:") || 211 !xfrd_read_check_str(in, "name:") || 212 !(p=xfrd_read_token(in)) || 213 !(dname = dname_parse(tempregion, p)) || 214 !xfrd_read_check_str(in, "state:") || 215 !xfrd_read_i32(in, &state) || (state>2) || 216 !xfrd_read_check_str(in, "master:") || 217 !xfrd_read_i32(in, &masnum) || 218 !xfrd_read_check_str(in, "next_master:") || 219 !xfrd_read_i32(in, &nextmas) || 220 !xfrd_read_check_str(in, "round_num:") || 221 !xfrd_read_i32(in, &round_num) || 222 !xfrd_read_check_str(in, "next_timeout:") || 223 !xfrd_read_i32(in, &timeout) || 224 !xfrd_read_check_str(in, "backoff:") || 225 !xfrd_read_i32(in, &backoff) || 226 !xfrd_read_state_soa(in, "soa_nsd_acquired:", "soa_nsd:", 227 &soa_nsd_read, &soa_nsd_acquired_read) || 228 !xfrd_read_state_soa(in, "soa_disk_acquired:", "soa_disk:", 229 &soa_disk_read, &soa_disk_acquired_read) || 230 !xfrd_read_state_soa(in, "soa_notify_acquired:", "soa_notify:", 231 &soa_notified_read, &soa_notified_acquired_read)) 232 { 233 log_msg(LOG_ERR, "xfrd: corrupt state file %s dated %d (now=%lld)", 234 statefile, (int)filetime, (long long)xfrd_time()); 235 fclose(in); 236 region_destroy(tempregion); 237 return; 238 } 239 240 zone = (xfrd_zone_type*)rbtree_search(xfrd->zones, dname); 241 if(!zone) { 242 DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: state file has info for not configured zone %s", p)); 243 continue; 244 } 245 246 if(soa_nsd_acquired_read>xfrd_time()+15 || 247 soa_disk_acquired_read>xfrd_time()+15 || 248 soa_notified_acquired_read>xfrd_time()+15) 249 { 250 log_msg(LOG_ERR, "xfrd: statefile %s contains" 251 " times in the future for zone %s. Ignoring.", 252 statefile, zone->apex_str); 253 continue; 254 } 255 zone->state = state; 256 zone->master_num = masnum; 257 zone->next_master = nextmas; 258 zone->round_num = round_num; 259 zone->timeout.tv_sec = timeout; 260 zone->timeout.tv_usec = 0; 261 zone->fresh_xfr_timeout = backoff*XFRD_TRANSFER_TIMEOUT_START; 262 263 /* read the zone OK, now set the master properly */ 264 zone->master = acl_find_num(zone->zone_options->pattern-> 265 request_xfr, zone->master_num); 266 if(!zone->master) { 267 DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: masters changed for zone %s", 268 zone->apex_str)); 269 zone->master = zone->zone_options->pattern->request_xfr; 270 zone->master_num = 0; 271 zone->round_num = 0; 272 } 273 274 /* 275 * There is no timeout, 276 * or there is a notification, 277 * or there is a soa && current time is past refresh point 278 */ 279 soa_refresh = ntohl(soa_disk_read.refresh); 280 if (soa_refresh > (time_t)zone->zone_options->pattern->max_refresh_time) 281 soa_refresh = zone->zone_options->pattern->max_refresh_time; 282 else if (soa_refresh < (time_t)zone->zone_options->pattern->min_refresh_time) 283 soa_refresh = zone->zone_options->pattern->min_refresh_time; 284 if(timeout == 0 || soa_notified_acquired_read != 0 || 285 (soa_disk_acquired_read != 0 && 286 (uint32_t)xfrd_time() - soa_disk_acquired_read 287 > (uint32_t)soa_refresh)) 288 { 289 zone->state = xfrd_zone_refreshing; 290 xfrd_set_refresh_now(zone); 291 } 292 if(timeout != 0 && filetime + timeout < (uint32_t)xfrd_time()) { 293 /* timeout is in the past, refresh the zone */ 294 timeout = 0; 295 if(zone->state == xfrd_zone_ok) 296 zone->state = xfrd_zone_refreshing; 297 xfrd_set_refresh_now(zone); 298 } 299 300 /* There is a soa && current time is past expiry point */ 301 if(soa_disk_acquired_read!=0 && 302 (uint32_t)xfrd_time() - soa_disk_acquired_read 303 > ntohl(soa_disk_read.expire)) 304 { 305 zone->state = xfrd_zone_expired; 306 xfrd_set_refresh_now(zone); 307 } 308 309 /* there is a zone read and it matches what we had before */ 310 if(zone->soa_nsd_acquired && zone->state != xfrd_zone_expired 311 && zone->soa_nsd.serial == soa_nsd_read.serial) { 312 xfrd_deactivate_zone(zone); 313 zone->state = state; 314 xfrd_set_timer(zone, timeout); 315 } 316 if((zone->soa_nsd_acquired == 0 && soa_nsd_acquired_read == 0 && 317 soa_disk_acquired_read == 0) || 318 (zone->state != xfrd_zone_ok && timeout != 0)) { 319 /* but don't check now, because that would mean a 320 * storm of attempts on some master servers */ 321 xfrd_deactivate_zone(zone); 322 zone->state = state; 323 xfrd_set_timer(zone, timeout); 324 } 325 326 /* handle as an incoming SOA. */ 327 incoming_soa = zone->soa_nsd; 328 incoming_acquired = zone->soa_nsd_acquired; 329 zone->soa_nsd = soa_nsd_read; 330 zone->soa_disk = soa_disk_read; 331 zone->soa_notified = soa_notified_read; 332 zone->soa_nsd_acquired = soa_nsd_acquired_read; 333 /* we had better use what we got from starting NSD, not 334 * what we store in this file, because the actual zone 335 * contents trumps the contents of this cache */ 336 /* zone->soa_disk_acquired = soa_disk_acquired_read; */ 337 zone->soa_notified_acquired = soa_notified_acquired_read; 338 if (zone->state == xfrd_zone_expired) 339 { 340 xfrd_send_expire_notification(zone); 341 } 342 if(incoming_acquired != 0) 343 xfrd_handle_incoming_soa(zone, &incoming_soa, incoming_acquired); 344 } 345 346 if(!xfrd_read_check_str(in, XFRD_FILE_MAGIC)) { 347 log_msg(LOG_ERR, "xfrd: corrupt state file %s dated %d (now=%lld)", 348 statefile, (int)filetime, (long long)xfrd_time()); 349 region_destroy(tempregion); 350 fclose(in); 351 return; 352 } 353 354 DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: read %d zones from state file", (int)numzones)); 355 fclose(in); 356 region_destroy(tempregion); 357 } 358 359 /* prints neato days hours and minutes. */ 360 static void 361 neato_timeout(FILE* out, const char* str, time_t secs) 362 { 363 fprintf(out, "%s", str); 364 if(secs <= 0) { 365 fprintf(out, " %llds", (long long)secs); 366 return; 367 } 368 if(secs >= 3600*24) { 369 fprintf(out, " %lldd", (long long)(secs/(3600*24))); 370 secs = secs % (3600*24); 371 } 372 if(secs >= 3600) { 373 fprintf(out, " %lldh", (long long)(secs/3600)); 374 secs = secs%3600; 375 } 376 if(secs >= 60) { 377 fprintf(out, " %lldm", (long long)(secs/60)); 378 secs = secs%60; 379 } 380 if(secs > 0) { 381 fprintf(out, " %llds", (long long)secs); 382 } 383 } 384 385 static void xfrd_write_dname(FILE* out, uint8_t* dname) 386 { 387 uint8_t* d= dname+1; 388 uint8_t len = *d++; 389 uint8_t i; 390 391 if(dname[0]<=1) { 392 fprintf(out, "."); 393 return; 394 } 395 396 while(len) 397 { 398 assert(d - (dname+1) <= dname[0]); 399 for(i=0; i<len; i++) 400 { 401 uint8_t ch = *d++; 402 if (isalnum((unsigned char)ch) || ch == '-' || ch == '_') { 403 fprintf(out, "%c", ch); 404 } else if (ch == '.' || ch == '\\') { 405 fprintf(out, "\\%c", ch); 406 } else { 407 fprintf(out, "\\%03u", (unsigned int)ch); 408 } 409 } 410 fprintf(out, "."); 411 len = *d++; 412 } 413 } 414 415 static void 416 xfrd_write_state_soa(FILE* out, const char* id, 417 xfrd_soa_type* soa, time_t soatime, const dname_type* ATTR_UNUSED(apex)) 418 { 419 fprintf(out, "\t%s_acquired: %d", id, (int)soatime); 420 if(!soatime) { 421 fprintf(out, "\n"); 422 return; 423 } 424 neato_timeout(out, "\t# was", xfrd_time()-soatime); 425 fprintf(out, " ago\n"); 426 427 fprintf(out, "\t%s: %u %u %u %u", id, 428 (unsigned)ntohs(soa->type), (unsigned)ntohs(soa->klass), 429 (unsigned)ntohl(soa->ttl), (unsigned)ntohs(soa->rdata_count)); 430 fprintf(out, " "); 431 xfrd_write_dname(out, soa->prim_ns); 432 fprintf(out, " "); 433 xfrd_write_dname(out, soa->email); 434 fprintf(out, " %u", (unsigned)ntohl(soa->serial)); 435 fprintf(out, " %u", (unsigned)ntohl(soa->refresh)); 436 fprintf(out, " %u", (unsigned)ntohl(soa->retry)); 437 fprintf(out, " %u", (unsigned)ntohl(soa->expire)); 438 fprintf(out, " %u\n", (unsigned)ntohl(soa->minimum)); 439 fprintf(out, "\t#"); 440 neato_timeout(out, " refresh =", ntohl(soa->refresh)); 441 neato_timeout(out, " retry =", ntohl(soa->retry)); 442 neato_timeout(out, " expire =", ntohl(soa->expire)); 443 neato_timeout(out, " minimum =", ntohl(soa->minimum)); 444 fprintf(out, "\n"); 445 } 446 447 void 448 xfrd_write_state(struct xfrd_state* xfrd) 449 { 450 rbnode_type* p; 451 const char* statefile = xfrd->nsd->options->xfrdfile; 452 FILE *out; 453 time_t now = xfrd_time(); 454 455 DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: write file %s", statefile)); 456 out = fopen(statefile, "w"); 457 if(!out) { 458 log_msg(LOG_ERR, "xfrd: Could not open file %s for writing: %s", 459 statefile, strerror(errno)); 460 return; 461 } 462 463 fprintf(out, "%s\n", XFRD_FILE_MAGIC); 464 fprintf(out, "# This file is written on exit by nsd xfr daemon.\n"); 465 fprintf(out, "# This file contains slave zone information:\n"); 466 fprintf(out, "# * timeouts (when was zone data acquired)\n"); 467 fprintf(out, "# * state (OK, refreshing, expired)\n"); 468 fprintf(out, "# * which master transfer to attempt next\n"); 469 fprintf(out, "# The file is read on start (but not on reload) by nsd xfr daemon.\n"); 470 fprintf(out, "# You can edit; but do not change statement order\n"); 471 fprintf(out, "# and no fancy stuff (like quoted \"strings\").\n"); 472 fprintf(out, "#\n"); 473 fprintf(out, "# If you remove a zone entry, it will be refreshed.\n"); 474 fprintf(out, "# This can be useful for an expired zone; it revives\n"); 475 fprintf(out, "# the zone temporarily, from refresh-expiry time.\n"); 476 fprintf(out, "# If you delete the file all slave zones are updated.\n"); 477 fprintf(out, "#\n"); 478 fprintf(out, "# Note: if you edit this file while nsd is running,\n"); 479 fprintf(out, "# it will be overwritten on exit by nsd.\n"); 480 fprintf(out, "\n"); 481 fprintf(out, "filetime: %lld\t# %s\n", (long long)now, ctime(&now)); 482 fprintf(out, "# The number of zone entries in this file\n"); 483 fprintf(out, "numzones: %d\n", (int)xfrd->zones->count); 484 fprintf(out, "\n"); 485 for(p = rbtree_first(xfrd->zones); p && p!=RBTREE_NULL; p=rbtree_next(p)) 486 { 487 xfrd_zone_type* zone = (xfrd_zone_type*)p; 488 fprintf(out, "zone: \tname: %s\n", zone->apex_str); 489 fprintf(out, "\tstate: %d", (int)zone->state); 490 fprintf(out, " # %s", zone->state==xfrd_zone_ok?"OK":( 491 zone->state==xfrd_zone_refreshing?"refreshing":"expired")); 492 fprintf(out, "\n"); 493 fprintf(out, "\tmaster: %d\n", zone->master_num); 494 fprintf(out, "\tnext_master: %d\n", zone->next_master); 495 fprintf(out, "\tround_num: %d\n", zone->round_num); 496 fprintf(out, "\tnext_timeout: %d", 497 (zone->zone_handler_flags&EV_TIMEOUT)?(int)zone->timeout.tv_sec:0); 498 if((zone->zone_handler_flags&EV_TIMEOUT)) { 499 neato_timeout(out, "\t# =", zone->timeout.tv_sec); 500 } 501 fprintf(out, "\n"); 502 fprintf(out, "\tbackoff: %d\n", zone->fresh_xfr_timeout/XFRD_TRANSFER_TIMEOUT_START); 503 xfrd_write_state_soa(out, "soa_nsd", &zone->soa_nsd, 504 zone->soa_nsd_acquired, zone->apex); 505 xfrd_write_state_soa(out, "soa_disk", &zone->soa_disk, 506 zone->soa_disk_acquired, zone->apex); 507 xfrd_write_state_soa(out, "soa_notify", &zone->soa_notified, 508 zone->soa_notified_acquired, zone->apex); 509 fprintf(out, "\n"); 510 } 511 512 fprintf(out, "%s\n", XFRD_FILE_MAGIC); 513 DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: written %d zones to state file", 514 (int)xfrd->zones->count)); 515 fclose(out); 516 } 517 518 /* return tempdirname */ 519 static void 520 tempdirname(char* buf, size_t sz, struct nsd* nsd) 521 { 522 snprintf(buf, sz, "%snsd-xfr-%d", 523 nsd->options->xfrdir, (int)nsd->pid); 524 } 525 526 void 527 xfrd_make_tempdir(struct nsd* nsd) 528 { 529 char tnm[1024]; 530 tempdirname(tnm, sizeof(tnm), nsd); 531 /* create parent directories if needed (0750 permissions) */ 532 if(!create_dirs(tnm)) { 533 log_msg(LOG_ERR, "parentdirs of %s failed", tnm); 534 } 535 /* restrictive permissions here, because this may be in /tmp */ 536 if(mkdir(tnm, 0700)==-1) { 537 if(errno != EEXIST) { 538 log_msg(LOG_ERR, "mkdir %s failed: %s", 539 tnm, strerror(errno)); 540 } 541 } 542 } 543 544 void 545 xfrd_del_tempdir(struct nsd* nsd) 546 { 547 char tnm[1024]; 548 tempdirname(tnm, sizeof(tnm), nsd); 549 /* ignore parent directories, they are likely /var/tmp, /tmp or 550 * /var/cache/nsd and do not have to be deleted */ 551 if(rmdir(tnm)==-1 && errno != ENOENT) { 552 log_msg(LOG_WARNING, "rmdir %s failed: %s", tnm, 553 strerror(errno)); 554 } 555 } 556 557 /* return name of xfrfile in tempdir */ 558 static void 559 tempxfrname(char* buf, size_t sz, struct nsd* nsd, uint64_t number) 560 { 561 char tnm[1024]; 562 tempdirname(tnm, sizeof(tnm), nsd); 563 snprintf(buf, sz, "%s/xfr.%lld", tnm, (long long)number); 564 } 565 566 FILE* 567 xfrd_open_xfrfile(struct nsd* nsd, uint64_t number, char* mode) 568 { 569 char fname[1200]; 570 FILE* xfr; 571 tempxfrname(fname, sizeof(fname), nsd, number); 572 xfr = fopen(fname, mode); 573 if(!xfr && errno == ENOENT) { 574 /* directory may not exist */ 575 xfrd_make_tempdir(nsd); 576 xfr = fopen(fname, mode); 577 } 578 if(!xfr) { 579 log_msg(LOG_ERR, "open %s for %s failed: %s", fname, mode, 580 strerror(errno)); 581 return NULL; 582 } 583 return xfr; 584 } 585 586 void 587 xfrd_unlink_xfrfile(struct nsd* nsd, uint64_t number) 588 { 589 char fname[1200]; 590 tempxfrname(fname, sizeof(fname), nsd, number); 591 if(unlink(fname) == -1) { 592 log_msg(LOG_WARNING, "could not unlink %s: %s", fname, 593 strerror(errno)); 594 } 595 } 596 597 uint64_t 598 xfrd_get_xfrfile_size(struct nsd* nsd, uint64_t number ) 599 { 600 char fname[1200]; 601 struct stat tempxfr_stat; 602 tempxfrname(fname, sizeof(fname), nsd, number); 603 if( stat( fname, &tempxfr_stat ) < 0 ) { 604 log_msg(LOG_WARNING, "could not get file size %s: %s", fname, 605 strerror(errno)); 606 return 0; 607 } 608 return (uint64_t)tempxfr_stat.st_size; 609 } 610