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_t* 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 !xfrd_read_check_str(in, "filetime:") || 170 !xfrd_read_i32(in, &filetime) || 171 (time_t)filetime > xfrd_time()+15 || 172 !xfrd_read_check_str(in, "numzones:") || 173 !xfrd_read_i32(in, &numzones)) 174 { 175 log_msg(LOG_ERR, "xfrd: corrupt state file %s dated %d (now=%lld)", 176 statefile, (int)filetime, (long long)xfrd_time()); 177 fclose(in); 178 region_destroy(tempregion); 179 return; 180 } 181 182 for(i=0; i<numzones; i++) { 183 char *p; 184 xfrd_zone_t* zone; 185 const dname_type* dname; 186 uint32_t state, masnum, nextmas, round_num, timeout; 187 xfrd_soa_t soa_nsd_read, soa_disk_read, soa_notified_read; 188 time_t soa_nsd_acquired_read, 189 soa_disk_acquired_read, soa_notified_acquired_read; 190 xfrd_soa_t incoming_soa; 191 time_t incoming_acquired; 192 193 if(nsd.signal_hint_shutdown) { 194 fclose(in); 195 region_destroy(tempregion); 196 return; 197 } 198 199 memset(&soa_nsd_read, 0, sizeof(soa_nsd_read)); 200 memset(&soa_disk_read, 0, sizeof(soa_disk_read)); 201 memset(&soa_notified_read, 0, sizeof(soa_notified_read)); 202 203 if(!xfrd_read_check_str(in, "zone:") || 204 !xfrd_read_check_str(in, "name:") || 205 !(p=xfrd_read_token(in)) || 206 !(dname = dname_parse(tempregion, p)) || 207 !xfrd_read_check_str(in, "state:") || 208 !xfrd_read_i32(in, &state) || (state>2) || 209 !xfrd_read_check_str(in, "master:") || 210 !xfrd_read_i32(in, &masnum) || 211 !xfrd_read_check_str(in, "next_master:") || 212 !xfrd_read_i32(in, &nextmas) || 213 !xfrd_read_check_str(in, "round_num:") || 214 !xfrd_read_i32(in, &round_num) || 215 !xfrd_read_check_str(in, "next_timeout:") || 216 !xfrd_read_i32(in, &timeout) || 217 !xfrd_read_state_soa(in, "soa_nsd_acquired:", "soa_nsd:", 218 &soa_nsd_read, &soa_nsd_acquired_read) || 219 !xfrd_read_state_soa(in, "soa_disk_acquired:", "soa_disk:", 220 &soa_disk_read, &soa_disk_acquired_read) || 221 !xfrd_read_state_soa(in, "soa_notify_acquired:", "soa_notify:", 222 &soa_notified_read, &soa_notified_acquired_read)) 223 { 224 log_msg(LOG_ERR, "xfrd: corrupt state file %s dated %d (now=%lld)", 225 statefile, (int)filetime, (long long)xfrd_time()); 226 fclose(in); 227 region_destroy(tempregion); 228 return; 229 } 230 231 zone = (xfrd_zone_t*)rbtree_search(xfrd->zones, dname); 232 if(!zone) { 233 DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: state file has info for not configured zone %s", p)); 234 continue; 235 } 236 237 if(soa_nsd_acquired_read>xfrd_time()+15 || 238 soa_disk_acquired_read>xfrd_time()+15 || 239 soa_notified_acquired_read>xfrd_time()+15) 240 { 241 log_msg(LOG_ERR, "xfrd: statefile %s contains" 242 " times in the future for zone %s. Ignoring.", 243 statefile, zone->apex_str); 244 continue; 245 } 246 zone->state = state; 247 zone->master_num = masnum; 248 zone->next_master = nextmas; 249 zone->round_num = round_num; 250 zone->timeout.tv_sec = timeout; 251 zone->timeout.tv_usec = 0; 252 253 /* read the zone OK, now set the master properly */ 254 zone->master = acl_find_num(zone->zone_options->pattern-> 255 request_xfr, zone->master_num); 256 if(!zone->master) { 257 DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: masters changed for zone %s", 258 zone->apex_str)); 259 zone->master = zone->zone_options->pattern->request_xfr; 260 zone->master_num = 0; 261 zone->round_num = 0; 262 } 263 264 /* 265 * There is no timeout, 266 * or there is a notification, 267 * or there is a soa && current time is past refresh point 268 */ 269 soa_refresh = ntohl(soa_disk_read.refresh); 270 if (soa_refresh > zone->zone_options->pattern->max_refresh_time) 271 soa_refresh = zone->zone_options->pattern->max_refresh_time; 272 else if (soa_refresh < zone->zone_options->pattern->min_refresh_time) 273 soa_refresh = zone->zone_options->pattern->min_refresh_time; 274 if(timeout == 0 || soa_notified_acquired_read != 0 || 275 (soa_disk_acquired_read != 0 && 276 (uint32_t)xfrd_time() - soa_disk_acquired_read 277 > soa_refresh)) 278 { 279 zone->state = xfrd_zone_refreshing; 280 xfrd_set_refresh_now(zone); 281 } 282 283 /* There is a soa && current time is past expiry point */ 284 if(soa_disk_acquired_read!=0 && 285 (uint32_t)xfrd_time() - soa_disk_acquired_read 286 > ntohl(soa_disk_read.expire)) 287 { 288 zone->state = xfrd_zone_expired; 289 xfrd_set_refresh_now(zone); 290 } 291 292 /* there is a zone read and it matches what we had before */ 293 if(zone->soa_nsd_acquired && zone->state != xfrd_zone_expired 294 && zone->soa_nsd.serial == soa_nsd_read.serial) { 295 xfrd_deactivate_zone(zone); 296 zone->state = state; 297 xfrd_set_timer(zone, timeout); 298 } 299 if(zone->soa_nsd_acquired == 0 && soa_nsd_acquired_read == 0 && 300 soa_disk_acquired_read == 0) { 301 /* continue expon backoff where we were + check now */ 302 zone->fresh_xfr_timeout = timeout; 303 } 304 305 /* handle as an incoming SOA. */ 306 incoming_soa = zone->soa_nsd; 307 incoming_acquired = zone->soa_nsd_acquired; 308 zone->soa_nsd = soa_nsd_read; 309 zone->soa_disk = soa_disk_read; 310 zone->soa_notified = soa_notified_read; 311 zone->soa_nsd_acquired = soa_nsd_acquired_read; 312 /* we had better use what we got from starting NSD, not 313 * what we store in this file, because the actual zone 314 * contents trumps the contents of this cache */ 315 /* zone->soa_disk_acquired = soa_disk_acquired_read; */ 316 zone->soa_notified_acquired = soa_notified_acquired_read; 317 if (zone->state == xfrd_zone_expired) 318 { 319 xfrd_send_expire_notification(zone); 320 } 321 xfrd_handle_incoming_soa(zone, &incoming_soa, incoming_acquired); 322 } 323 324 if(!xfrd_read_check_str(in, XFRD_FILE_MAGIC)) { 325 log_msg(LOG_ERR, "xfrd: corrupt state file %s dated %d (now=%lld)", 326 statefile, (int)filetime, (long long)xfrd_time()); 327 region_destroy(tempregion); 328 fclose(in); 329 return; 330 } 331 332 DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: read %d zones from state file", (int)numzones)); 333 fclose(in); 334 region_destroy(tempregion); 335 } 336 337 /* prints neato days hours and minutes. */ 338 static void 339 neato_timeout(FILE* out, const char* str, time_t secs) 340 { 341 fprintf(out, "%s", str); 342 if(secs <= 0) { 343 fprintf(out, " %llds", (long long)secs); 344 return; 345 } 346 if(secs >= 3600*24) { 347 fprintf(out, " %lldd", (long long)(secs/(3600*24))); 348 secs = secs % (3600*24); 349 } 350 if(secs >= 3600) { 351 fprintf(out, " %lldh", (long long)(secs/3600)); 352 secs = secs%3600; 353 } 354 if(secs >= 60) { 355 fprintf(out, " %lldm", (long long)(secs/60)); 356 secs = secs%60; 357 } 358 if(secs > 0) { 359 fprintf(out, " %llds", (long long)secs); 360 } 361 } 362 363 static void xfrd_write_dname(FILE* out, uint8_t* dname) 364 { 365 uint8_t* d= dname+1; 366 uint8_t len = *d++; 367 uint8_t i; 368 369 if(dname[0]<=1) { 370 fprintf(out, "."); 371 return; 372 } 373 374 while(len) 375 { 376 assert(d - (dname+1) <= dname[0]); 377 for(i=0; i<len; i++) 378 { 379 uint8_t ch = *d++; 380 if (isalnum((unsigned char)ch) || ch == '-' || ch == '_') { 381 fprintf(out, "%c", ch); 382 } else if (ch == '.' || ch == '\\') { 383 fprintf(out, "\\%c", ch); 384 } else { 385 fprintf(out, "\\%03u", (unsigned int)ch); 386 } 387 } 388 fprintf(out, "."); 389 len = *d++; 390 } 391 } 392 393 static void 394 xfrd_write_state_soa(FILE* out, const char* id, 395 xfrd_soa_t* soa, time_t soatime, const dname_type* ATTR_UNUSED(apex)) 396 { 397 fprintf(out, "\t%s_acquired: %d", id, (int)soatime); 398 if(!soatime) { 399 fprintf(out, "\n"); 400 return; 401 } 402 neato_timeout(out, "\t# was", xfrd_time()-soatime); 403 fprintf(out, " ago\n"); 404 405 fprintf(out, "\t%s: %u %u %u %u", id, 406 (unsigned)ntohs(soa->type), (unsigned)ntohs(soa->klass), 407 (unsigned)ntohl(soa->ttl), (unsigned)ntohs(soa->rdata_count)); 408 fprintf(out, " "); 409 xfrd_write_dname(out, soa->prim_ns); 410 fprintf(out, " "); 411 xfrd_write_dname(out, soa->email); 412 fprintf(out, " %u", (unsigned)ntohl(soa->serial)); 413 fprintf(out, " %u", (unsigned)ntohl(soa->refresh)); 414 fprintf(out, " %u", (unsigned)ntohl(soa->retry)); 415 fprintf(out, " %u", (unsigned)ntohl(soa->expire)); 416 fprintf(out, " %u\n", (unsigned)ntohl(soa->minimum)); 417 fprintf(out, "\t#"); 418 neato_timeout(out, " refresh =", ntohl(soa->refresh)); 419 neato_timeout(out, " retry =", ntohl(soa->retry)); 420 neato_timeout(out, " expire =", ntohl(soa->expire)); 421 neato_timeout(out, " minimum =", ntohl(soa->minimum)); 422 fprintf(out, "\n"); 423 } 424 425 void 426 xfrd_write_state(struct xfrd_state* xfrd) 427 { 428 rbnode_t* p; 429 const char* statefile = xfrd->nsd->options->xfrdfile; 430 FILE *out; 431 time_t now = xfrd_time(); 432 433 DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: write file %s", statefile)); 434 out = fopen(statefile, "w"); 435 if(!out) { 436 log_msg(LOG_ERR, "xfrd: Could not open file %s for writing: %s", 437 statefile, strerror(errno)); 438 return; 439 } 440 441 fprintf(out, "%s\n", XFRD_FILE_MAGIC); 442 fprintf(out, "# This file is written on exit by nsd xfr daemon.\n"); 443 fprintf(out, "# This file contains slave zone information:\n"); 444 fprintf(out, "# * timeouts (when was zone data acquired)\n"); 445 fprintf(out, "# * state (OK, refreshing, expired)\n"); 446 fprintf(out, "# * which master transfer to attempt next\n"); 447 fprintf(out, "# The file is read on start (but not on reload) by nsd xfr daemon.\n"); 448 fprintf(out, "# You can edit; but do not change statement order\n"); 449 fprintf(out, "# and no fancy stuff (like quoted \"strings\").\n"); 450 fprintf(out, "#\n"); 451 fprintf(out, "# If you remove a zone entry, it will be refreshed.\n"); 452 fprintf(out, "# This can be useful for an expired zone; it revives\n"); 453 fprintf(out, "# the zone temporarily, from refresh-expiry time.\n"); 454 fprintf(out, "# If you delete the file all slave zones are updated.\n"); 455 fprintf(out, "#\n"); 456 fprintf(out, "# Note: if you edit this file while nsd is running,\n"); 457 fprintf(out, "# it will be overwritten on exit by nsd.\n"); 458 fprintf(out, "\n"); 459 fprintf(out, "filetime: %lld\t# %s\n", (long long)now, ctime(&now)); 460 fprintf(out, "# The number of zone entries in this file\n"); 461 fprintf(out, "numzones: %d\n", (int)xfrd->zones->count); 462 fprintf(out, "\n"); 463 for(p = rbtree_first(xfrd->zones); p && p!=RBTREE_NULL; p=rbtree_next(p)) 464 { 465 xfrd_zone_t* zone = (xfrd_zone_t*)p; 466 fprintf(out, "zone: \tname: %s\n", zone->apex_str); 467 fprintf(out, "\tstate: %d", (int)zone->state); 468 fprintf(out, " # %s", zone->state==xfrd_zone_ok?"OK":( 469 zone->state==xfrd_zone_refreshing?"refreshing":"expired")); 470 fprintf(out, "\n"); 471 fprintf(out, "\tmaster: %d\n", zone->master_num); 472 fprintf(out, "\tnext_master: %d\n", zone->next_master); 473 fprintf(out, "\tround_num: %d\n", zone->round_num); 474 fprintf(out, "\tnext_timeout: %d", 475 (zone->zone_handler_flags&EV_TIMEOUT)?(int)zone->timeout.tv_sec:0); 476 if((zone->zone_handler_flags&EV_TIMEOUT)) { 477 neato_timeout(out, "\t# =", zone->timeout.tv_sec); 478 } 479 fprintf(out, "\n"); 480 xfrd_write_state_soa(out, "soa_nsd", &zone->soa_nsd, 481 zone->soa_nsd_acquired, zone->apex); 482 xfrd_write_state_soa(out, "soa_disk", &zone->soa_disk, 483 zone->soa_disk_acquired, zone->apex); 484 xfrd_write_state_soa(out, "soa_notify", &zone->soa_notified, 485 zone->soa_notified_acquired, zone->apex); 486 fprintf(out, "\n"); 487 } 488 489 fprintf(out, "%s\n", XFRD_FILE_MAGIC); 490 DEBUG(DEBUG_XFRD,1, (LOG_INFO, "xfrd: written %d zones to state file", 491 (int)xfrd->zones->count)); 492 fclose(out); 493 } 494 495 /* return tempdirname */ 496 static void 497 tempdirname(char* buf, size_t sz, struct nsd* nsd) 498 { 499 snprintf(buf, sz, "%snsd-xfr-%d", 500 nsd->options->xfrdir, (int)nsd->pid); 501 } 502 503 void 504 xfrd_make_tempdir(struct nsd* nsd) 505 { 506 char tnm[1024]; 507 tempdirname(tnm, sizeof(tnm), nsd); 508 /* create parent directories if needed (0750 permissions) */ 509 if(!create_dirs(tnm)) { 510 log_msg(LOG_ERR, "parentdirs of %s failed", tnm); 511 } 512 /* restrictive permissions here, because this may be in /tmp */ 513 if(mkdir(tnm, 0700)==-1) { 514 if(errno != EEXIST) { 515 log_msg(LOG_ERR, "mkdir %s failed: %s", 516 tnm, strerror(errno)); 517 } 518 } 519 } 520 521 void 522 xfrd_del_tempdir(struct nsd* nsd) 523 { 524 char tnm[1024]; 525 tempdirname(tnm, sizeof(tnm), nsd); 526 /* ignore parent directories, they are likely /var/tmp, /tmp or 527 * /var/cache/nsd and do not have to be deleted */ 528 if(rmdir(tnm)==-1 && errno != ENOENT) { 529 log_msg(LOG_WARNING, "rmdir %s failed: %s", tnm, 530 strerror(errno)); 531 } 532 } 533 534 /* return name of xfrfile in tempdir */ 535 static void 536 tempxfrname(char* buf, size_t sz, struct nsd* nsd, uint64_t number) 537 { 538 char tnm[1024]; 539 tempdirname(tnm, sizeof(tnm), nsd); 540 snprintf(buf, sz, "%s/xfr.%lld", tnm, (long long)number); 541 } 542 543 FILE* 544 xfrd_open_xfrfile(struct nsd* nsd, uint64_t number, char* mode) 545 { 546 char fname[1024]; 547 FILE* xfr; 548 tempxfrname(fname, sizeof(fname), nsd, number); 549 xfr = fopen(fname, mode); 550 if(!xfr && errno == ENOENT) { 551 /* directory may not exist */ 552 xfrd_make_tempdir(nsd); 553 xfr = fopen(fname, mode); 554 } 555 if(!xfr) { 556 log_msg(LOG_ERR, "open %s for %s failed: %s", fname, mode, 557 strerror(errno)); 558 return NULL; 559 } 560 return xfr; 561 } 562 563 void 564 xfrd_unlink_xfrfile(struct nsd* nsd, uint64_t number) 565 { 566 char fname[1024]; 567 tempxfrname(fname, sizeof(fname), nsd, number); 568 if(unlink(fname) == -1) { 569 log_msg(LOG_WARNING, "could not unlink %s: %s", fname, 570 strerror(errno)); 571 } 572 } 573 574 uint64_t 575 xfrd_get_xfrfile_size(struct nsd* nsd, uint64_t number ) 576 { 577 char fname[1024]; 578 struct stat tempxfr_stat; 579 tempxfrname(fname, sizeof(fname), nsd, number); 580 if( stat( fname, &tempxfr_stat ) < 0 ) { 581 log_msg(LOG_WARNING, "could not get file size %s: %s", fname, 582 strerror(errno)); 583 return 0; 584 } 585 return (uint64_t)tempxfr_stat.st_size; 586 } 587