1 /* $OpenBSD: queue_fs.c,v 1.20 2020/02/25 17:03:13 millert Exp $ */ 2 3 /* 4 * Copyright (c) 2011 Gilles Chehade <gilles@poolp.org> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 #include <sys/types.h> 20 #include <sys/mount.h> 21 #include <sys/queue.h> 22 #include <sys/tree.h> 23 #include <sys/socket.h> 24 #include <sys/stat.h> 25 26 #include <ctype.h> 27 #include <dirent.h> 28 #include <err.h> 29 #include <errno.h> 30 #include <event.h> 31 #include <fcntl.h> 32 #include <fts.h> 33 #include <imsg.h> 34 #include <inttypes.h> 35 #include <pwd.h> 36 #include <stdio.h> 37 #include <stdlib.h> 38 #include <string.h> 39 #include <time.h> 40 #include <unistd.h> 41 42 #include "smtpd.h" 43 #include "log.h" 44 45 #define PATH_QUEUE "/queue" 46 #define PATH_INCOMING "/incoming" 47 #define PATH_EVPTMP PATH_INCOMING "/envelope.tmp" 48 #define PATH_MESSAGE "/message" 49 50 /* percentage of remaining space / inodes required to accept new messages */ 51 #define MINSPACE 5 52 #define MININODES 5 53 54 struct qwalk { 55 FTS *fts; 56 int depth; 57 }; 58 59 static int fsqueue_check_space(void); 60 static void fsqueue_envelope_path(uint64_t, char *, size_t); 61 static void fsqueue_envelope_incoming_path(uint64_t, char *, size_t); 62 static int fsqueue_envelope_dump(char *, const char *, size_t, int, int); 63 static void fsqueue_message_path(uint32_t, char *, size_t); 64 static void fsqueue_message_incoming_path(uint32_t, char *, size_t); 65 static void *fsqueue_qwalk_new(void); 66 static int fsqueue_qwalk(void *, uint64_t *); 67 static void fsqueue_qwalk_close(void *); 68 69 struct tree evpcount; 70 static struct timespec startup; 71 72 #define REF (int*)0xf00 73 74 static int 75 queue_fs_message_create(uint32_t *msgid) 76 { 77 char rootdir[PATH_MAX]; 78 struct stat sb; 79 80 if (!fsqueue_check_space()) 81 return 0; 82 83 again: 84 *msgid = queue_generate_msgid(); 85 86 /* prevent possible collision later when moving to Q_QUEUE */ 87 fsqueue_message_path(*msgid, rootdir, sizeof(rootdir)); 88 if (stat(rootdir, &sb) != -1) 89 goto again; 90 91 /* we hit an unexpected error, temporarily fail */ 92 if (errno != ENOENT) { 93 *msgid = 0; 94 return 0; 95 } 96 97 fsqueue_message_incoming_path(*msgid, rootdir, sizeof(rootdir)); 98 if (mkdir(rootdir, 0700) == -1) { 99 if (errno == EEXIST) 100 goto again; 101 102 if (errno == ENOSPC) { 103 *msgid = 0; 104 return 0; 105 } 106 107 log_warn("warn: queue-fs: mkdir"); 108 *msgid = 0; 109 return 0; 110 } 111 112 return (1); 113 } 114 115 static int 116 queue_fs_message_commit(uint32_t msgid, const char *path) 117 { 118 char incomingdir[PATH_MAX]; 119 char queuedir[PATH_MAX]; 120 char msgdir[PATH_MAX]; 121 char msgpath[PATH_MAX]; 122 123 /* before-first, move the message content in the incoming directory */ 124 fsqueue_message_incoming_path(msgid, msgpath, sizeof(msgpath)); 125 if (strlcat(msgpath, PATH_MESSAGE, sizeof(msgpath)) 126 >= sizeof(msgpath)) 127 return (0); 128 if (rename(path, msgpath) == -1) 129 return (0); 130 131 fsqueue_message_incoming_path(msgid, incomingdir, sizeof(incomingdir)); 132 fsqueue_message_path(msgid, msgdir, sizeof(msgdir)); 133 if (strlcpy(queuedir, msgdir, sizeof(queuedir)) 134 >= sizeof(queuedir)) 135 return (0); 136 137 /* first attempt to rename */ 138 if (rename(incomingdir, msgdir) == 0) 139 return 1; 140 if (errno == ENOSPC) 141 return 0; 142 if (errno != ENOENT) { 143 log_warn("warn: queue-fs: rename"); 144 return 0; 145 } 146 147 /* create the bucket */ 148 *strrchr(queuedir, '/') = '\0'; 149 if (mkdir(queuedir, 0700) == -1) { 150 if (errno == ENOSPC) 151 return 0; 152 if (errno != EEXIST) { 153 log_warn("warn: queue-fs: mkdir"); 154 return 0; 155 } 156 } 157 158 /* rename */ 159 if (rename(incomingdir, msgdir) == -1) { 160 if (errno == ENOSPC) 161 return 0; 162 log_warn("warn: queue-fs: rename"); 163 return 0; 164 } 165 166 return 1; 167 } 168 169 static int 170 queue_fs_message_fd_r(uint32_t msgid) 171 { 172 int fd; 173 char path[PATH_MAX]; 174 175 fsqueue_message_path(msgid, path, sizeof(path)); 176 if (strlcat(path, PATH_MESSAGE, sizeof(path)) 177 >= sizeof(path)) 178 return -1; 179 180 if ((fd = open(path, O_RDONLY)) == -1) { 181 log_warn("warn: queue-fs: open"); 182 return -1; 183 } 184 185 return fd; 186 } 187 188 static int 189 queue_fs_message_delete(uint32_t msgid) 190 { 191 char path[PATH_MAX]; 192 struct stat sb; 193 194 fsqueue_message_incoming_path(msgid, path, sizeof(path)); 195 if (stat(path, &sb) == -1) 196 fsqueue_message_path(msgid, path, sizeof(path)); 197 198 if (rmtree(path, 0) == -1) 199 log_warn("warn: queue-fs: rmtree"); 200 201 tree_pop(&evpcount, msgid); 202 203 return 1; 204 } 205 206 static int 207 queue_fs_envelope_create(uint32_t msgid, const char *buf, size_t len, 208 uint64_t *evpid) 209 { 210 char path[PATH_MAX]; 211 int queued = 0, i, r = 0, *n; 212 struct stat sb; 213 214 if (msgid == 0) { 215 log_warnx("warn: queue-fs: msgid=0, evpid=%016"PRIx64, *evpid); 216 goto done; 217 } 218 219 fsqueue_message_incoming_path(msgid, path, sizeof(path)); 220 if (stat(path, &sb) == -1) 221 queued = 1; 222 223 for (i = 0; i < 20; i ++) { 224 *evpid = queue_generate_evpid(msgid); 225 if (queued) 226 fsqueue_envelope_path(*evpid, path, sizeof(path)); 227 else 228 fsqueue_envelope_incoming_path(*evpid, path, 229 sizeof(path)); 230 231 if ((r = fsqueue_envelope_dump(path, buf, len, 0, 0)) != 0) 232 goto done; 233 } 234 r = 0; 235 log_warnx("warn: queue-fs: could not allocate evpid"); 236 237 done: 238 if (r) { 239 n = tree_pop(&evpcount, msgid); 240 if (n == NULL) 241 n = REF; 242 n += 1; 243 tree_xset(&evpcount, msgid, n); 244 } 245 return (r); 246 } 247 248 static int 249 queue_fs_envelope_load(uint64_t evpid, char *buf, size_t len) 250 { 251 char pathname[PATH_MAX]; 252 FILE *fp; 253 size_t r; 254 255 fsqueue_envelope_path(evpid, pathname, sizeof(pathname)); 256 257 fp = fopen(pathname, "r"); 258 if (fp == NULL) { 259 if (errno != ENOENT && errno != ENFILE) 260 log_warn("warn: queue-fs: fopen"); 261 return 0; 262 } 263 264 r = fread(buf, 1, len, fp); 265 if (r) { 266 if (r == len) { 267 log_warn("warn: queue-fs: too large"); 268 r = 0; 269 } 270 else 271 buf[r] = '\0'; 272 } 273 fclose(fp); 274 275 return (r); 276 } 277 278 static int 279 queue_fs_envelope_update(uint64_t evpid, const char *buf, size_t len) 280 { 281 char dest[PATH_MAX]; 282 283 fsqueue_envelope_path(evpid, dest, sizeof(dest)); 284 285 return (fsqueue_envelope_dump(dest, buf, len, 1, 1)); 286 } 287 288 static int 289 queue_fs_envelope_delete(uint64_t evpid) 290 { 291 char pathname[PATH_MAX]; 292 uint32_t msgid; 293 int *n; 294 295 fsqueue_envelope_path(evpid, pathname, sizeof(pathname)); 296 if (unlink(pathname) == -1) 297 if (errno != ENOENT) 298 return 0; 299 300 msgid = evpid_to_msgid(evpid); 301 n = tree_pop(&evpcount, msgid); 302 n -= 1; 303 304 if (n - REF == 0) 305 queue_fs_message_delete(msgid); 306 else 307 tree_xset(&evpcount, msgid, n); 308 309 return (1); 310 } 311 312 static int 313 queue_fs_message_walk(uint64_t *evpid, char *buf, size_t len, 314 uint32_t msgid, int *done, void **data) 315 { 316 struct dirent *dp; 317 DIR *dir = *data; 318 char path[PATH_MAX]; 319 char msgid_str[9]; 320 char *tmp; 321 int r, *n; 322 323 if (*done) 324 return (-1); 325 326 if (!bsnprintf(path, sizeof path, "%s/%02x/%08x", 327 PATH_QUEUE, (msgid & 0xff000000) >> 24, msgid)) 328 fatalx("queue_fs_message_walk: path does not fit buffer"); 329 330 if (dir == NULL) { 331 if ((dir = opendir(path)) == NULL) { 332 log_warn("warn: queue_fs: opendir: %s", path); 333 *done = 1; 334 return (-1); 335 } 336 337 *data = dir; 338 } 339 340 (void)snprintf(msgid_str, sizeof msgid_str, "%08" PRIx32, msgid); 341 while ((dp = readdir(dir)) != NULL) { 342 if (dp->d_type != DT_REG) 343 continue; 344 345 /* ignore files other than envelopes */ 346 if (strlen(dp->d_name) != 16 || 347 strncmp(dp->d_name, msgid_str, 8)) 348 continue; 349 350 tmp = NULL; 351 *evpid = strtoull(dp->d_name, &tmp, 16); 352 if (tmp && *tmp != '\0') { 353 log_debug("debug: fsqueue: bogus file %s", dp->d_name); 354 continue; 355 } 356 357 memset(buf, 0, len); 358 r = queue_fs_envelope_load(*evpid, buf, len); 359 if (r) { 360 n = tree_pop(&evpcount, msgid); 361 if (n == NULL) 362 n = REF; 363 364 n += 1; 365 tree_xset(&evpcount, msgid, n); 366 } 367 368 return (r); 369 } 370 371 (void)closedir(dir); 372 *done = 1; 373 return (-1); 374 } 375 376 static int 377 queue_fs_envelope_walk(uint64_t *evpid, char *buf, size_t len) 378 { 379 static int done = 0; 380 static void *hdl = NULL; 381 int r, *n; 382 uint32_t msgid; 383 384 if (done) 385 return (-1); 386 387 if (hdl == NULL) 388 hdl = fsqueue_qwalk_new(); 389 390 if (fsqueue_qwalk(hdl, evpid)) { 391 memset(buf, 0, len); 392 r = queue_fs_envelope_load(*evpid, buf, len); 393 if (r) { 394 msgid = evpid_to_msgid(*evpid); 395 n = tree_pop(&evpcount, msgid); 396 if (n == NULL) 397 n = REF; 398 n += 1; 399 tree_xset(&evpcount, msgid, n); 400 } 401 return (r); 402 } 403 404 fsqueue_qwalk_close(hdl); 405 done = 1; 406 return (-1); 407 } 408 409 static int 410 fsqueue_check_space(void) 411 { 412 struct statfs buf; 413 uint64_t used; 414 uint64_t total; 415 416 if (statfs(PATH_QUEUE, &buf) == -1) { 417 log_warn("warn: queue-fs: statfs"); 418 return 0; 419 } 420 421 /* 422 * f_bfree and f_ffree is not set on all filesystems. 423 * They could be signed or unsigned integers. 424 * Some systems will set them to 0, others will set them to -1. 425 */ 426 if (buf.f_bfree == 0 || buf.f_ffree == 0 || 427 (int64_t)buf.f_bfree == -1 || (int64_t)buf.f_ffree == -1) 428 return 1; 429 430 used = buf.f_blocks - buf.f_bfree; 431 total = buf.f_bavail + used; 432 if (total != 0) 433 used = (float)used / (float)total * 100; 434 else 435 used = 100; 436 if (100 - used < MINSPACE) { 437 log_warnx("warn: not enough disk space: %llu%% left", 438 (unsigned long long) 100 - used); 439 log_warnx("warn: temporarily rejecting messages"); 440 return 0; 441 } 442 443 used = buf.f_files - buf.f_ffree; 444 total = buf.f_favail + used; 445 if (total != 0) 446 used = (float)used / (float)total * 100; 447 else 448 used = 100; 449 if (100 - used < MININODES) { 450 log_warnx("warn: not enough inodes: %llu%% left", 451 (unsigned long long) 100 - used); 452 log_warnx("warn: temporarily rejecting messages"); 453 return 0; 454 } 455 456 return 1; 457 } 458 459 static void 460 fsqueue_envelope_path(uint64_t evpid, char *buf, size_t len) 461 { 462 if (!bsnprintf(buf, len, "%s/%02x/%08x/%016" PRIx64, 463 PATH_QUEUE, 464 (evpid_to_msgid(evpid) & 0xff000000) >> 24, 465 evpid_to_msgid(evpid), 466 evpid)) 467 fatalx("fsqueue_envelope_path: path does not fit buffer"); 468 } 469 470 static void 471 fsqueue_envelope_incoming_path(uint64_t evpid, char *buf, size_t len) 472 { 473 if (!bsnprintf(buf, len, "%s/%08x/%016" PRIx64, 474 PATH_INCOMING, 475 evpid_to_msgid(evpid), 476 evpid)) 477 fatalx("fsqueue_envelope_incoming_path: path does not fit buffer"); 478 } 479 480 static int 481 fsqueue_envelope_dump(char *dest, const char *evpbuf, size_t evplen, 482 int do_atomic, int do_sync) 483 { 484 const char *path = do_atomic ? PATH_EVPTMP : dest; 485 FILE *fp = NULL; 486 int fd; 487 size_t w; 488 489 if ((fd = open(path, O_RDWR | O_CREAT | O_EXCL, 0600)) == -1) { 490 log_warn("warn: queue-fs: open"); 491 goto tempfail; 492 } 493 494 if ((fp = fdopen(fd, "w")) == NULL) { 495 log_warn("warn: queue-fs: fdopen"); 496 goto tempfail; 497 } 498 499 w = fwrite(evpbuf, 1, evplen, fp); 500 if (w < evplen) { 501 log_warn("warn: queue-fs: short write"); 502 goto tempfail; 503 } 504 if (fflush(fp)) { 505 log_warn("warn: queue-fs: fflush"); 506 goto tempfail; 507 } 508 if (do_sync && fsync(fileno(fp))) { 509 log_warn("warn: queue-fs: fsync"); 510 goto tempfail; 511 } 512 if (fclose(fp) != 0) { 513 log_warn("warn: queue-fs: fclose"); 514 fp = NULL; 515 goto tempfail; 516 } 517 fp = NULL; 518 fd = -1; 519 520 if (do_atomic && rename(path, dest) == -1) { 521 log_warn("warn: queue-fs: rename"); 522 goto tempfail; 523 } 524 return (1); 525 526 tempfail: 527 if (fp) 528 fclose(fp); 529 else if (fd != -1) 530 close(fd); 531 if (unlink(path) == -1) 532 log_warn("warn: queue-fs: unlink"); 533 return (0); 534 } 535 536 static void 537 fsqueue_message_path(uint32_t msgid, char *buf, size_t len) 538 { 539 if (!bsnprintf(buf, len, "%s/%02x/%08x", 540 PATH_QUEUE, 541 (msgid & 0xff000000) >> 24, 542 msgid)) 543 fatalx("fsqueue_message_path: path does not fit buffer"); 544 } 545 546 static void 547 fsqueue_message_incoming_path(uint32_t msgid, char *buf, size_t len) 548 { 549 if (!bsnprintf(buf, len, "%s/%08x", 550 PATH_INCOMING, 551 msgid)) 552 fatalx("fsqueue_message_incoming_path: path does not fit buffer"); 553 } 554 555 static void * 556 fsqueue_qwalk_new(void) 557 { 558 char path[PATH_MAX]; 559 char * const path_argv[] = { path, NULL }; 560 struct qwalk *q; 561 562 q = xcalloc(1, sizeof(*q)); 563 (void)strlcpy(path, PATH_QUEUE, sizeof(path)); 564 q->fts = fts_open(path_argv, 565 FTS_PHYSICAL | FTS_NOCHDIR, NULL); 566 567 if (q->fts == NULL) 568 err(1, "fsqueue_qwalk_new: fts_open: %s", path); 569 570 return (q); 571 } 572 573 static void 574 fsqueue_qwalk_close(void *hdl) 575 { 576 struct qwalk *q = hdl; 577 578 fts_close(q->fts); 579 580 free(q); 581 } 582 583 static int 584 fsqueue_qwalk(void *hdl, uint64_t *evpid) 585 { 586 struct qwalk *q = hdl; 587 FTSENT *e; 588 char *tmp; 589 590 while ((e = fts_read(q->fts)) != NULL) { 591 switch (e->fts_info) { 592 case FTS_D: 593 q->depth += 1; 594 if (q->depth == 2 && e->fts_namelen != 2) { 595 log_debug("debug: fsqueue: bogus directory %s", 596 e->fts_path); 597 fts_set(q->fts, e, FTS_SKIP); 598 break; 599 } 600 if (q->depth == 3 && e->fts_namelen != 8) { 601 log_debug("debug: fsqueue: bogus directory %s", 602 e->fts_path); 603 fts_set(q->fts, e, FTS_SKIP); 604 break; 605 } 606 break; 607 608 case FTS_DP: 609 case FTS_DNR: 610 q->depth -= 1; 611 break; 612 613 case FTS_F: 614 if (q->depth != 3) 615 break; 616 if (e->fts_namelen != 16) 617 break; 618 if (timespeccmp(&e->fts_statp->st_mtim, &startup, >)) 619 break; 620 tmp = NULL; 621 *evpid = strtoull(e->fts_name, &tmp, 16); 622 if (tmp && *tmp != '\0') { 623 log_debug("debug: fsqueue: bogus file %s", 624 e->fts_path); 625 break; 626 } 627 return (1); 628 default: 629 break; 630 } 631 } 632 633 return (0); 634 } 635 636 static int 637 queue_fs_init(struct passwd *pw, int server, const char *conf) 638 { 639 unsigned int n; 640 char *paths[] = { PATH_QUEUE, PATH_INCOMING }; 641 char path[PATH_MAX]; 642 int ret; 643 644 /* remove incoming/ if it exists */ 645 if (server) 646 mvpurge(PATH_SPOOL PATH_INCOMING, PATH_SPOOL PATH_PURGE); 647 648 fsqueue_envelope_path(0, path, sizeof(path)); 649 650 ret = 1; 651 for (n = 0; n < nitems(paths); n++) { 652 (void)strlcpy(path, PATH_SPOOL, sizeof(path)); 653 if (strlcat(path, paths[n], sizeof(path)) >= sizeof(path)) 654 errx(1, "path too long %s%s", PATH_SPOOL, paths[n]); 655 if (ckdir(path, 0700, pw->pw_uid, 0, server) == 0) 656 ret = 0; 657 } 658 659 if (clock_gettime(CLOCK_REALTIME, &startup)) 660 err(1, "clock_gettime"); 661 662 tree_init(&evpcount); 663 664 queue_api_on_message_create(queue_fs_message_create); 665 queue_api_on_message_commit(queue_fs_message_commit); 666 queue_api_on_message_delete(queue_fs_message_delete); 667 queue_api_on_message_fd_r(queue_fs_message_fd_r); 668 queue_api_on_envelope_create(queue_fs_envelope_create); 669 queue_api_on_envelope_delete(queue_fs_envelope_delete); 670 queue_api_on_envelope_update(queue_fs_envelope_update); 671 queue_api_on_envelope_load(queue_fs_envelope_load); 672 queue_api_on_envelope_walk(queue_fs_envelope_walk); 673 queue_api_on_message_walk(queue_fs_message_walk); 674 675 return (ret); 676 } 677 678 struct queue_backend queue_backend_fs = { 679 queue_fs_init, 680 }; 681