1 /* $OpenBSD: misc.c,v 1.208 2025/09/25 06:33:19 djm Exp $ */ 2 /* 3 * Copyright (c) 2000 Markus Friedl. All rights reserved. 4 * Copyright (c) 2005-2020 Damien Miller. All rights reserved. 5 * Copyright (c) 2004 Henning Brauer <henning@openbsd.org> 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 21 #include "includes.h" 22 23 #include <sys/types.h> 24 #include <sys/ioctl.h> 25 #include <sys/mman.h> 26 #include <sys/socket.h> 27 #include <sys/stat.h> 28 #include <sys/time.h> 29 #include <sys/wait.h> 30 #include <sys/un.h> 31 32 #include <limits.h> 33 #include <libgen.h> 34 #include <poll.h> 35 #include <nlist.h> 36 #include <signal.h> 37 #include <stdarg.h> 38 #include <stdio.h> 39 #include <stdint.h> 40 #include <stdlib.h> 41 #include <string.h> 42 #include <time.h> 43 #include <unistd.h> 44 45 #include <netinet/in.h> 46 #include <netinet/in_systm.h> 47 #include <netinet/ip.h> 48 #include <netinet/tcp.h> 49 #include <arpa/inet.h> 50 51 #include <ctype.h> 52 #include <errno.h> 53 #include <fcntl.h> 54 #include <netdb.h> 55 #include <paths.h> 56 #include <pwd.h> 57 #include <grp.h> 58 #ifdef SSH_TUN_OPENBSD 59 #include <net/if.h> 60 #endif 61 62 #include "xmalloc.h" 63 #include "misc.h" 64 #include "log.h" 65 #include "ssh.h" 66 #include "sshbuf.h" 67 #include "ssherr.h" 68 #include "platform.h" 69 70 /* remove newline at end of string */ 71 char * 72 chop(char *s) 73 { 74 char *t = s; 75 while (*t) { 76 if (*t == '\n' || *t == '\r') { 77 *t = '\0'; 78 return s; 79 } 80 t++; 81 } 82 return s; 83 84 } 85 86 /* remove whitespace from end of string */ 87 void 88 rtrim(char *s) 89 { 90 size_t i; 91 92 if ((i = strlen(s)) == 0) 93 return; 94 do { 95 i--; 96 if (isspace((unsigned char)s[i])) 97 s[i] = '\0'; 98 else 99 break; 100 } while (i > 0); 101 } 102 103 /* 104 * returns pointer to character after 'prefix' in 's' or otherwise NULL 105 * if the prefix is not present. 106 */ 107 const char * 108 strprefix(const char *s, const char *prefix, int ignorecase) 109 { 110 size_t prefixlen; 111 112 if ((prefixlen = strlen(prefix)) == 0) 113 return s; 114 if (ignorecase) { 115 if (strncasecmp(s, prefix, prefixlen) != 0) 116 return NULL; 117 } else { 118 if (strncmp(s, prefix, prefixlen) != 0) 119 return NULL; 120 } 121 return s + prefixlen; 122 } 123 124 /* set/unset filedescriptor to non-blocking */ 125 int 126 set_nonblock(int fd) 127 { 128 int val; 129 130 val = fcntl(fd, F_GETFL); 131 if (val == -1) { 132 error("fcntl(%d, F_GETFL): %s", fd, strerror(errno)); 133 return (-1); 134 } 135 if (val & O_NONBLOCK) { 136 debug3("fd %d is O_NONBLOCK", fd); 137 return (0); 138 } 139 debug2("fd %d setting O_NONBLOCK", fd); 140 val |= O_NONBLOCK; 141 if (fcntl(fd, F_SETFL, val) == -1) { 142 debug("fcntl(%d, F_SETFL, O_NONBLOCK): %s", fd, 143 strerror(errno)); 144 return (-1); 145 } 146 return (0); 147 } 148 149 int 150 unset_nonblock(int fd) 151 { 152 int val; 153 154 val = fcntl(fd, F_GETFL); 155 if (val == -1) { 156 error("fcntl(%d, F_GETFL): %s", fd, strerror(errno)); 157 return (-1); 158 } 159 if (!(val & O_NONBLOCK)) { 160 debug3("fd %d is not O_NONBLOCK", fd); 161 return (0); 162 } 163 debug("fd %d clearing O_NONBLOCK", fd); 164 val &= ~O_NONBLOCK; 165 if (fcntl(fd, F_SETFL, val) == -1) { 166 debug("fcntl(%d, F_SETFL, ~O_NONBLOCK): %s", 167 fd, strerror(errno)); 168 return (-1); 169 } 170 return (0); 171 } 172 173 const char * 174 ssh_gai_strerror(int gaierr) 175 { 176 if (gaierr == EAI_SYSTEM && errno != 0) 177 return strerror(errno); 178 return gai_strerror(gaierr); 179 } 180 181 /* disable nagle on socket */ 182 void 183 set_nodelay(int fd) 184 { 185 int opt; 186 socklen_t optlen; 187 188 optlen = sizeof opt; 189 if (getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, &optlen) == -1) { 190 debug("getsockopt TCP_NODELAY: %.100s", strerror(errno)); 191 return; 192 } 193 if (opt == 1) { 194 debug2("fd %d is TCP_NODELAY", fd); 195 return; 196 } 197 opt = 1; 198 debug2("fd %d setting TCP_NODELAY", fd); 199 if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof opt) == -1) 200 error("setsockopt TCP_NODELAY: %.100s", strerror(errno)); 201 } 202 203 /* Allow local port reuse in TIME_WAIT */ 204 int 205 set_reuseaddr(int fd) 206 { 207 int on = 1; 208 209 if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) { 210 error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno)); 211 return -1; 212 } 213 return 0; 214 } 215 216 /* Get/set routing domain */ 217 char * 218 get_rdomain(int fd) 219 { 220 #if defined(HAVE_SYS_GET_RDOMAIN) 221 return sys_get_rdomain(fd); 222 #elif defined(__OpenBSD__) 223 int rtable; 224 char *ret; 225 socklen_t len = sizeof(rtable); 226 227 if (getsockopt(fd, SOL_SOCKET, SO_RTABLE, &rtable, &len) == -1) { 228 error("Failed to get routing domain for fd %d: %s", 229 fd, strerror(errno)); 230 return NULL; 231 } 232 xasprintf(&ret, "%d", rtable); 233 return ret; 234 #else /* defined(__OpenBSD__) */ 235 return NULL; 236 #endif 237 } 238 239 int 240 set_rdomain(int fd, const char *name) 241 { 242 #if defined(HAVE_SYS_SET_RDOMAIN) 243 return sys_set_rdomain(fd, name); 244 #elif defined(__OpenBSD__) 245 int rtable; 246 const char *errstr; 247 248 if (name == NULL) 249 return 0; /* default table */ 250 251 rtable = (int)strtonum(name, 0, 255, &errstr); 252 if (errstr != NULL) { 253 /* Shouldn't happen */ 254 error("Invalid routing domain \"%s\": %s", name, errstr); 255 return -1; 256 } 257 if (setsockopt(fd, SOL_SOCKET, SO_RTABLE, 258 &rtable, sizeof(rtable)) == -1) { 259 error("Failed to set routing domain %d on fd %d: %s", 260 rtable, fd, strerror(errno)); 261 return -1; 262 } 263 return 0; 264 #else /* defined(__OpenBSD__) */ 265 error("Setting routing domain is not supported on this platform"); 266 return -1; 267 #endif 268 } 269 270 int 271 get_sock_af(int fd) 272 { 273 struct sockaddr_storage to; 274 socklen_t tolen = sizeof(to); 275 276 memset(&to, 0, sizeof(to)); 277 if (getsockname(fd, (struct sockaddr *)&to, &tolen) == -1) 278 return -1; 279 #ifdef IPV4_IN_IPV6 280 if (to.ss_family == AF_INET6 && 281 IN6_IS_ADDR_V4MAPPED(&((struct sockaddr_in6 *)&to)->sin6_addr)) 282 return AF_INET; 283 #endif 284 return to.ss_family; 285 } 286 287 void 288 set_sock_tos(int fd, int tos) 289 { 290 #ifndef IP_TOS_IS_BROKEN 291 int af; 292 293 if (tos < 0 || tos == INT_MAX) { 294 debug_f("invalid TOS %d", tos); 295 return; 296 } 297 switch ((af = get_sock_af(fd))) { 298 case -1: 299 /* assume not a socket */ 300 break; 301 case AF_INET: 302 # ifdef IP_TOS 303 debug3_f("set socket %d IP_TOS 0x%02x", fd, tos); 304 if (setsockopt(fd, IPPROTO_IP, IP_TOS, 305 &tos, sizeof(tos)) == -1) { 306 error("setsockopt socket %d IP_TOS %d: %s", 307 fd, tos, strerror(errno)); 308 } 309 # endif /* IP_TOS */ 310 break; 311 case AF_INET6: 312 # ifdef IPV6_TCLASS 313 debug3_f("set socket %d IPV6_TCLASS 0x%02x", fd, tos); 314 if (setsockopt(fd, IPPROTO_IPV6, IPV6_TCLASS, 315 &tos, sizeof(tos)) == -1) { 316 error("setsockopt socket %d IPV6_TCLASS %d: %s", 317 fd, tos, strerror(errno)); 318 } 319 # endif /* IPV6_TCLASS */ 320 break; 321 default: 322 debug2_f("unsupported socket family %d", af); 323 break; 324 } 325 #endif /* IP_TOS_IS_BROKEN */ 326 } 327 328 /* 329 * Wait up to *timeoutp milliseconds for events on fd. Updates 330 * *timeoutp with time remaining. 331 * Returns 0 if fd ready or -1 on timeout or error (see errno). 332 */ 333 static int 334 waitfd(int fd, int *timeoutp, short events, volatile sig_atomic_t *stop) 335 { 336 struct pollfd pfd; 337 struct timespec timeout; 338 int oerrno, r; 339 sigset_t nsigset, osigset; 340 341 if (timeoutp && *timeoutp == -1) 342 timeoutp = NULL; 343 pfd.fd = fd; 344 pfd.events = events; 345 ptimeout_init(&timeout); 346 if (timeoutp != NULL) 347 ptimeout_deadline_ms(&timeout, *timeoutp); 348 if (stop != NULL) 349 sigfillset(&nsigset); 350 for (; timeoutp == NULL || *timeoutp >= 0;) { 351 if (stop != NULL) { 352 sigprocmask(SIG_BLOCK, &nsigset, &osigset); 353 if (*stop) { 354 sigprocmask(SIG_SETMASK, &osigset, NULL); 355 errno = EINTR; 356 return -1; 357 } 358 } 359 r = ppoll(&pfd, 1, ptimeout_get_tsp(&timeout), 360 stop != NULL ? &osigset : NULL); 361 oerrno = errno; 362 if (stop != NULL) 363 sigprocmask(SIG_SETMASK, &osigset, NULL); 364 if (timeoutp) 365 *timeoutp = ptimeout_get_ms(&timeout); 366 errno = oerrno; 367 if (r > 0) 368 return 0; 369 else if (r == -1 && errno != EAGAIN && errno != EINTR) 370 return -1; 371 else if (r == 0) 372 break; 373 } 374 /* timeout */ 375 errno = ETIMEDOUT; 376 return -1; 377 } 378 379 /* 380 * Wait up to *timeoutp milliseconds for fd to be readable. Updates 381 * *timeoutp with time remaining. 382 * Returns 0 if fd ready or -1 on timeout or error (see errno). 383 */ 384 int 385 waitrfd(int fd, int *timeoutp, volatile sig_atomic_t *stop) { 386 return waitfd(fd, timeoutp, POLLIN, stop); 387 } 388 389 /* 390 * Attempt a non-blocking connect(2) to the specified address, waiting up to 391 * *timeoutp milliseconds for the connection to complete. If the timeout is 392 * <=0, then wait indefinitely. 393 * 394 * Returns 0 on success or -1 on failure. 395 */ 396 int 397 timeout_connect(int sockfd, const struct sockaddr *serv_addr, 398 socklen_t addrlen, int *timeoutp) 399 { 400 int optval = 0; 401 socklen_t optlen = sizeof(optval); 402 403 /* No timeout: just do a blocking connect() */ 404 if (timeoutp == NULL || *timeoutp <= 0) 405 return connect(sockfd, serv_addr, addrlen); 406 407 set_nonblock(sockfd); 408 for (;;) { 409 if (connect(sockfd, serv_addr, addrlen) == 0) { 410 /* Succeeded already? */ 411 unset_nonblock(sockfd); 412 return 0; 413 } else if (errno == EINTR) 414 continue; 415 else if (errno != EINPROGRESS) 416 return -1; 417 break; 418 } 419 420 if (waitfd(sockfd, timeoutp, POLLIN | POLLOUT, NULL) == -1) 421 return -1; 422 423 /* Completed or failed */ 424 if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &optval, &optlen) == -1) { 425 debug("getsockopt: %s", strerror(errno)); 426 return -1; 427 } 428 if (optval != 0) { 429 errno = optval; 430 return -1; 431 } 432 unset_nonblock(sockfd); 433 return 0; 434 } 435 436 /* Characters considered whitespace in strsep calls. */ 437 #define WHITESPACE " \t\r\n" 438 #define QUOTE "\"" 439 440 /* return next token in configuration line */ 441 static char * 442 strdelim_internal(char **s, int split_equals) 443 { 444 char *old; 445 int wspace = 0; 446 447 if (*s == NULL) 448 return NULL; 449 450 old = *s; 451 452 *s = strpbrk(*s, 453 split_equals ? WHITESPACE QUOTE "=" : WHITESPACE QUOTE); 454 if (*s == NULL) 455 return (old); 456 457 if (*s[0] == '\"') { 458 memmove(*s, *s + 1, strlen(*s)); /* move nul too */ 459 /* Find matching quote */ 460 if ((*s = strpbrk(*s, QUOTE)) == NULL) { 461 return (NULL); /* no matching quote */ 462 } else { 463 *s[0] = '\0'; 464 *s += strspn(*s + 1, WHITESPACE) + 1; 465 return (old); 466 } 467 } 468 469 /* Allow only one '=' to be skipped */ 470 if (split_equals && *s[0] == '=') 471 wspace = 1; 472 *s[0] = '\0'; 473 474 /* Skip any extra whitespace after first token */ 475 *s += strspn(*s + 1, WHITESPACE) + 1; 476 if (split_equals && *s[0] == '=' && !wspace) 477 *s += strspn(*s + 1, WHITESPACE) + 1; 478 479 return (old); 480 } 481 482 /* 483 * Return next token in configuration line; splits on whitespace or a 484 * single '=' character. 485 */ 486 char * 487 strdelim(char **s) 488 { 489 return strdelim_internal(s, 1); 490 } 491 492 /* 493 * Return next token in configuration line; splits on whitespace only. 494 */ 495 char * 496 strdelimw(char **s) 497 { 498 return strdelim_internal(s, 0); 499 } 500 501 struct passwd * 502 pwcopy(struct passwd *pw) 503 { 504 struct passwd *copy = xcalloc(1, sizeof(*copy)); 505 506 copy->pw_name = xstrdup(pw->pw_name); 507 copy->pw_passwd = xstrdup(pw->pw_passwd == NULL ? "*" : pw->pw_passwd); 508 #ifdef HAVE_STRUCT_PASSWD_PW_GECOS 509 copy->pw_gecos = xstrdup(pw->pw_gecos == NULL ? "" : pw->pw_gecos); 510 #endif 511 copy->pw_uid = pw->pw_uid; 512 copy->pw_gid = pw->pw_gid; 513 #ifdef HAVE_STRUCT_PASSWD_PW_EXPIRE 514 copy->pw_expire = pw->pw_expire; 515 #endif 516 #ifdef HAVE_STRUCT_PASSWD_PW_CHANGE 517 copy->pw_change = pw->pw_change; 518 #endif 519 #ifdef HAVE_STRUCT_PASSWD_PW_CLASS 520 copy->pw_class = xstrdup(pw->pw_class == NULL ? "" : pw->pw_class); 521 #endif 522 copy->pw_dir = xstrdup(pw->pw_dir == NULL ? "" : pw->pw_dir); 523 copy->pw_shell = xstrdup(pw->pw_shell == NULL ? "" : pw->pw_shell); 524 return copy; 525 } 526 527 void 528 pwfree(struct passwd *pw) 529 { 530 if (pw == NULL) 531 return; 532 free(pw->pw_name); 533 freezero(pw->pw_passwd, 534 pw->pw_passwd == NULL ? 0 : strlen(pw->pw_passwd)); 535 #ifdef HAVE_STRUCT_PASSWD_PW_GECOS 536 free(pw->pw_gecos); 537 #endif 538 #ifdef HAVE_STRUCT_PASSWD_PW_CLASS 539 free(pw->pw_class); 540 #endif 541 free(pw->pw_dir); 542 free(pw->pw_shell); 543 freezero(pw, sizeof(*pw)); 544 } 545 546 /* 547 * Convert ASCII string to TCP/IP port number. 548 * Port must be >=0 and <=65535. 549 * Return -1 if invalid. 550 */ 551 int 552 a2port(const char *s) 553 { 554 struct servent *se; 555 long long port; 556 const char *errstr; 557 558 port = strtonum(s, 0, 65535, &errstr); 559 if (errstr == NULL) 560 return (int)port; 561 if ((se = getservbyname(s, "tcp")) != NULL) 562 return ntohs(se->s_port); 563 return -1; 564 } 565 566 int 567 a2tun(const char *s, int *remote) 568 { 569 const char *errstr = NULL; 570 char *sp, *ep; 571 int tun; 572 573 if (remote != NULL) { 574 *remote = SSH_TUNID_ANY; 575 sp = xstrdup(s); 576 if ((ep = strchr(sp, ':')) == NULL) { 577 free(sp); 578 return (a2tun(s, NULL)); 579 } 580 ep[0] = '\0'; ep++; 581 *remote = a2tun(ep, NULL); 582 tun = a2tun(sp, NULL); 583 free(sp); 584 return (*remote == SSH_TUNID_ERR ? *remote : tun); 585 } 586 587 if (strcasecmp(s, "any") == 0) 588 return (SSH_TUNID_ANY); 589 590 tun = strtonum(s, 0, SSH_TUNID_MAX, &errstr); 591 if (errstr != NULL) 592 return (SSH_TUNID_ERR); 593 594 return (tun); 595 } 596 597 #define SECONDS 1 598 #define MINUTES (SECONDS * 60) 599 #define HOURS (MINUTES * 60) 600 #define DAYS (HOURS * 24) 601 #define WEEKS (DAYS * 7) 602 603 static char * 604 scandigits(char *s) 605 { 606 while (isdigit((unsigned char)*s)) 607 s++; 608 return s; 609 } 610 611 /* 612 * Convert a time string into seconds; format is 613 * a sequence of: 614 * time[qualifier] 615 * 616 * Valid time qualifiers are: 617 * <none> seconds 618 * s|S seconds 619 * m|M minutes 620 * h|H hours 621 * d|D days 622 * w|W weeks 623 * 624 * Examples: 625 * 90m 90 minutes 626 * 1h30m 90 minutes 627 * 2d 2 days 628 * 1w 1 week 629 * 630 * Return -1 if time string is invalid. 631 */ 632 int 633 convtime(const char *s) 634 { 635 int secs, total = 0, multiplier; 636 char *p, *os, *np, c = 0; 637 const char *errstr; 638 639 if (s == NULL || *s == '\0') 640 return -1; 641 p = os = strdup(s); /* deal with const */ 642 if (os == NULL) 643 return -1; 644 645 while (*p) { 646 np = scandigits(p); 647 if (np) { 648 c = *np; 649 *np = '\0'; 650 } 651 secs = (int)strtonum(p, 0, INT_MAX, &errstr); 652 if (errstr) 653 goto fail; 654 *np = c; 655 656 multiplier = 1; 657 switch (c) { 658 case '\0': 659 np--; /* back up */ 660 break; 661 case 's': 662 case 'S': 663 break; 664 case 'm': 665 case 'M': 666 multiplier = MINUTES; 667 break; 668 case 'h': 669 case 'H': 670 multiplier = HOURS; 671 break; 672 case 'd': 673 case 'D': 674 multiplier = DAYS; 675 break; 676 case 'w': 677 case 'W': 678 multiplier = WEEKS; 679 break; 680 default: 681 goto fail; 682 } 683 if (secs > INT_MAX / multiplier) 684 goto fail; 685 secs *= multiplier; 686 if (total > INT_MAX - secs) 687 goto fail; 688 total += secs; 689 if (total < 0) 690 goto fail; 691 p = ++np; 692 } 693 free(os); 694 return total; 695 fail: 696 free(os); 697 return -1; 698 } 699 700 #define TF_BUFS 8 701 #define TF_LEN 9 702 703 const char * 704 fmt_timeframe(time_t t) 705 { 706 char *buf; 707 static char tfbuf[TF_BUFS][TF_LEN]; /* ring buffer */ 708 static int idx = 0; 709 unsigned int sec, min, hrs, day; 710 unsigned long long week; 711 712 buf = tfbuf[idx++]; 713 if (idx == TF_BUFS) 714 idx = 0; 715 716 week = t; 717 718 sec = week % 60; 719 week /= 60; 720 min = week % 60; 721 week /= 60; 722 hrs = week % 24; 723 week /= 24; 724 day = week % 7; 725 week /= 7; 726 727 if (week > 0) 728 snprintf(buf, TF_LEN, "%02lluw%01ud%02uh", week, day, hrs); 729 else if (day > 0) 730 snprintf(buf, TF_LEN, "%01ud%02uh%02um", day, hrs, min); 731 else 732 snprintf(buf, TF_LEN, "%02u:%02u:%02u", hrs, min, sec); 733 734 return (buf); 735 } 736 737 /* 738 * Returns a standardized host+port identifier string. 739 * Caller must free returned string. 740 */ 741 char * 742 put_host_port(const char *host, u_short port) 743 { 744 char *hoststr; 745 746 if (port == 0 || port == SSH_DEFAULT_PORT) 747 return(xstrdup(host)); 748 if (asprintf(&hoststr, "[%s]:%d", host, (int)port) == -1) 749 fatal("put_host_port: asprintf: %s", strerror(errno)); 750 debug3("put_host_port: %s", hoststr); 751 return hoststr; 752 } 753 754 /* 755 * Search for next delimiter between hostnames/addresses and ports. 756 * Argument may be modified (for termination). 757 * Returns *cp if parsing succeeds. 758 * *cp is set to the start of the next field, if one was found. 759 * The delimiter char, if present, is stored in delim. 760 * If this is the last field, *cp is set to NULL. 761 */ 762 char * 763 hpdelim2(char **cp, char *delim) 764 { 765 char *s, *old; 766 767 if (cp == NULL || *cp == NULL) 768 return NULL; 769 770 old = s = *cp; 771 if (*s == '[') { 772 if ((s = strchr(s, ']')) == NULL) 773 return NULL; 774 else 775 s++; 776 } else if ((s = strpbrk(s, ":/")) == NULL) 777 s = *cp + strlen(*cp); /* skip to end (see first case below) */ 778 779 switch (*s) { 780 case '\0': 781 *cp = NULL; /* no more fields*/ 782 break; 783 784 case ':': 785 case '/': 786 if (delim != NULL) 787 *delim = *s; 788 *s = '\0'; /* terminate */ 789 *cp = s + 1; 790 break; 791 792 default: 793 return NULL; 794 } 795 796 return old; 797 } 798 799 /* The common case: only accept colon as delimiter. */ 800 char * 801 hpdelim(char **cp) 802 { 803 char *r, delim = '\0'; 804 805 r = hpdelim2(cp, &delim); 806 if (delim == '/') 807 return NULL; 808 return r; 809 } 810 811 char * 812 cleanhostname(char *host) 813 { 814 if (*host == '[' && host[strlen(host) - 1] == ']') { 815 host[strlen(host) - 1] = '\0'; 816 return (host + 1); 817 } else 818 return host; 819 } 820 821 char * 822 colon(char *cp) 823 { 824 int flag = 0; 825 826 if (*cp == ':') /* Leading colon is part of file name. */ 827 return NULL; 828 if (*cp == '[') 829 flag = 1; 830 831 for (; *cp; ++cp) { 832 if (*cp == '@' && *(cp+1) == '[') 833 flag = 1; 834 if (*cp == ']' && *(cp+1) == ':' && flag) 835 return (cp+1); 836 if (*cp == ':' && !flag) 837 return (cp); 838 if (*cp == '/') 839 return NULL; 840 } 841 return NULL; 842 } 843 844 /* 845 * Parse a [user@]host:[path] string. 846 * Caller must free returned user, host and path. 847 * Any of the pointer return arguments may be NULL (useful for syntax checking). 848 * If user was not specified then *userp will be set to NULL. 849 * If host was not specified then *hostp will be set to NULL. 850 * If path was not specified then *pathp will be set to ".". 851 * Returns 0 on success, -1 on failure. 852 */ 853 int 854 parse_user_host_path(const char *s, char **userp, char **hostp, char **pathp) 855 { 856 char *user = NULL, *host = NULL, *path = NULL; 857 char *sdup, *tmp; 858 int ret = -1; 859 860 if (userp != NULL) 861 *userp = NULL; 862 if (hostp != NULL) 863 *hostp = NULL; 864 if (pathp != NULL) 865 *pathp = NULL; 866 867 sdup = xstrdup(s); 868 869 /* Check for remote syntax: [user@]host:[path] */ 870 if ((tmp = colon(sdup)) == NULL) 871 goto out; 872 873 /* Extract optional path */ 874 *tmp++ = '\0'; 875 if (*tmp == '\0') 876 tmp = "."; 877 path = xstrdup(tmp); 878 879 /* Extract optional user and mandatory host */ 880 tmp = strrchr(sdup, '@'); 881 if (tmp != NULL) { 882 *tmp++ = '\0'; 883 host = xstrdup(cleanhostname(tmp)); 884 if (*sdup != '\0') 885 user = xstrdup(sdup); 886 } else { 887 host = xstrdup(cleanhostname(sdup)); 888 user = NULL; 889 } 890 891 /* Success */ 892 if (userp != NULL) { 893 *userp = user; 894 user = NULL; 895 } 896 if (hostp != NULL) { 897 *hostp = host; 898 host = NULL; 899 } 900 if (pathp != NULL) { 901 *pathp = path; 902 path = NULL; 903 } 904 ret = 0; 905 out: 906 free(sdup); 907 free(user); 908 free(host); 909 free(path); 910 return ret; 911 } 912 913 /* 914 * Parse a [user@]host[:port] string. 915 * Caller must free returned user and host. 916 * Any of the pointer return arguments may be NULL (useful for syntax checking). 917 * If user was not specified then *userp will be set to NULL. 918 * If port was not specified then *portp will be -1. 919 * Returns 0 on success, -1 on failure. 920 */ 921 int 922 parse_user_host_port(const char *s, char **userp, char **hostp, int *portp) 923 { 924 char *sdup, *cp, *tmp; 925 char *user = NULL, *host = NULL; 926 int port = -1, ret = -1; 927 928 if (userp != NULL) 929 *userp = NULL; 930 if (hostp != NULL) 931 *hostp = NULL; 932 if (portp != NULL) 933 *portp = -1; 934 935 if ((sdup = tmp = strdup(s)) == NULL) 936 return -1; 937 /* Extract optional username */ 938 if ((cp = strrchr(tmp, '@')) != NULL) { 939 *cp = '\0'; 940 if (*tmp == '\0') 941 goto out; 942 if ((user = strdup(tmp)) == NULL) 943 goto out; 944 tmp = cp + 1; 945 } 946 /* Extract mandatory hostname */ 947 if ((cp = hpdelim(&tmp)) == NULL || *cp == '\0') 948 goto out; 949 host = xstrdup(cleanhostname(cp)); 950 /* Convert and verify optional port */ 951 if (tmp != NULL && *tmp != '\0') { 952 if ((port = a2port(tmp)) <= 0) 953 goto out; 954 } 955 /* Success */ 956 if (userp != NULL) { 957 *userp = user; 958 user = NULL; 959 } 960 if (hostp != NULL) { 961 *hostp = host; 962 host = NULL; 963 } 964 if (portp != NULL) 965 *portp = port; 966 ret = 0; 967 out: 968 free(sdup); 969 free(user); 970 free(host); 971 return ret; 972 } 973 974 /* 975 * Converts a two-byte hex string to decimal. 976 * Returns the decimal value or -1 for invalid input. 977 */ 978 static int 979 hexchar(const char *s) 980 { 981 unsigned char result[2]; 982 int i; 983 984 for (i = 0; i < 2; i++) { 985 if (s[i] >= '0' && s[i] <= '9') 986 result[i] = (unsigned char)(s[i] - '0'); 987 else if (s[i] >= 'a' && s[i] <= 'f') 988 result[i] = (unsigned char)(s[i] - 'a') + 10; 989 else if (s[i] >= 'A' && s[i] <= 'F') 990 result[i] = (unsigned char)(s[i] - 'A') + 10; 991 else 992 return -1; 993 } 994 return (result[0] << 4) | result[1]; 995 } 996 997 /* 998 * Decode an url-encoded string. 999 * Returns a newly allocated string on success or NULL on failure. 1000 */ 1001 static char * 1002 urldecode(const char *src) 1003 { 1004 char *ret, *dst; 1005 int ch; 1006 size_t srclen; 1007 1008 if ((srclen = strlen(src)) >= SIZE_MAX) 1009 return NULL; 1010 ret = xmalloc(srclen + 1); 1011 for (dst = ret; *src != '\0'; src++) { 1012 switch (*src) { 1013 case '+': 1014 *dst++ = ' '; 1015 break; 1016 case '%': 1017 /* note: don't allow \0 characters */ 1018 if (!isxdigit((unsigned char)src[1]) || 1019 !isxdigit((unsigned char)src[2]) || 1020 (ch = hexchar(src + 1)) == -1 || ch == 0) { 1021 free(ret); 1022 return NULL; 1023 } 1024 *dst++ = ch; 1025 src += 2; 1026 break; 1027 default: 1028 *dst++ = *src; 1029 break; 1030 } 1031 } 1032 *dst = '\0'; 1033 1034 return ret; 1035 } 1036 1037 /* 1038 * Parse an (scp|ssh|sftp)://[user@]host[:port][/path] URI. 1039 * See https://tools.ietf.org/html/draft-ietf-secsh-scp-sftp-ssh-uri-04 1040 * Either user or path may be url-encoded (but not host or port). 1041 * Caller must free returned user, host and path. 1042 * Any of the pointer return arguments may be NULL (useful for syntax checking) 1043 * but the scheme must always be specified. 1044 * If user was not specified then *userp will be set to NULL. 1045 * If port was not specified then *portp will be -1. 1046 * If path was not specified then *pathp will be set to NULL. 1047 * Returns 0 on success, 1 if non-uri/wrong scheme, -1 on error/invalid uri. 1048 */ 1049 int 1050 parse_uri(const char *scheme, const char *uri, char **userp, char **hostp, 1051 int *portp, char **pathp) 1052 { 1053 char *uridup, *cp, *tmp, ch; 1054 char *user = NULL, *host = NULL, *path = NULL; 1055 int port = -1, ret = -1; 1056 size_t len; 1057 1058 len = strlen(scheme); 1059 if (strncmp(uri, scheme, len) != 0 || strncmp(uri + len, "://", 3) != 0) 1060 return 1; 1061 uri += len + 3; 1062 1063 if (userp != NULL) 1064 *userp = NULL; 1065 if (hostp != NULL) 1066 *hostp = NULL; 1067 if (portp != NULL) 1068 *portp = -1; 1069 if (pathp != NULL) 1070 *pathp = NULL; 1071 1072 uridup = tmp = xstrdup(uri); 1073 1074 /* Extract optional ssh-info (username + connection params) */ 1075 if ((cp = strchr(tmp, '@')) != NULL) { 1076 char *delim; 1077 1078 *cp = '\0'; 1079 /* Extract username and connection params */ 1080 if ((delim = strchr(tmp, ';')) != NULL) { 1081 /* Just ignore connection params for now */ 1082 *delim = '\0'; 1083 } 1084 if (*tmp == '\0') { 1085 /* Empty username */ 1086 goto out; 1087 } 1088 if ((user = urldecode(tmp)) == NULL) 1089 goto out; 1090 tmp = cp + 1; 1091 } 1092 1093 /* Extract mandatory hostname */ 1094 if ((cp = hpdelim2(&tmp, &ch)) == NULL || *cp == '\0') 1095 goto out; 1096 host = xstrdup(cleanhostname(cp)); 1097 if (!valid_domain(host, 0, NULL)) 1098 goto out; 1099 1100 if (tmp != NULL && *tmp != '\0') { 1101 if (ch == ':') { 1102 /* Convert and verify port. */ 1103 if ((cp = strchr(tmp, '/')) != NULL) 1104 *cp = '\0'; 1105 if ((port = a2port(tmp)) <= 0) 1106 goto out; 1107 tmp = cp ? cp + 1 : NULL; 1108 } 1109 if (tmp != NULL && *tmp != '\0') { 1110 /* Extract optional path */ 1111 if ((path = urldecode(tmp)) == NULL) 1112 goto out; 1113 } 1114 } 1115 1116 /* Success */ 1117 if (userp != NULL) { 1118 *userp = user; 1119 user = NULL; 1120 } 1121 if (hostp != NULL) { 1122 *hostp = host; 1123 host = NULL; 1124 } 1125 if (portp != NULL) 1126 *portp = port; 1127 if (pathp != NULL) { 1128 *pathp = path; 1129 path = NULL; 1130 } 1131 ret = 0; 1132 out: 1133 free(uridup); 1134 free(user); 1135 free(host); 1136 free(path); 1137 return ret; 1138 } 1139 1140 /* function to assist building execv() arguments */ 1141 void 1142 addargs(arglist *args, char *fmt, ...) 1143 { 1144 va_list ap; 1145 char *cp; 1146 u_int nalloc; 1147 int r; 1148 1149 va_start(ap, fmt); 1150 r = vasprintf(&cp, fmt, ap); 1151 va_end(ap); 1152 if (r == -1) 1153 fatal_f("argument too long"); 1154 1155 nalloc = args->nalloc; 1156 if (args->list == NULL) { 1157 nalloc = 32; 1158 args->num = 0; 1159 } else if (args->num > (256 * 1024)) 1160 fatal_f("too many arguments"); 1161 else if (args->num >= args->nalloc) 1162 fatal_f("arglist corrupt"); 1163 else if (args->num+2 >= nalloc) 1164 nalloc *= 2; 1165 1166 args->list = xrecallocarray(args->list, args->nalloc, 1167 nalloc, sizeof(char *)); 1168 args->nalloc = nalloc; 1169 args->list[args->num++] = cp; 1170 args->list[args->num] = NULL; 1171 } 1172 1173 void 1174 replacearg(arglist *args, u_int which, char *fmt, ...) 1175 { 1176 va_list ap; 1177 char *cp; 1178 int r; 1179 1180 va_start(ap, fmt); 1181 r = vasprintf(&cp, fmt, ap); 1182 va_end(ap); 1183 if (r == -1) 1184 fatal_f("argument too long"); 1185 if (args->list == NULL || args->num >= args->nalloc) 1186 fatal_f("arglist corrupt"); 1187 1188 if (which >= args->num) 1189 fatal_f("tried to replace invalid arg %d >= %d", 1190 which, args->num); 1191 free(args->list[which]); 1192 args->list[which] = cp; 1193 } 1194 1195 void 1196 freeargs(arglist *args) 1197 { 1198 u_int i; 1199 1200 if (args == NULL) 1201 return; 1202 if (args->list != NULL && args->num < args->nalloc) { 1203 for (i = 0; i < args->num; i++) 1204 free(args->list[i]); 1205 free(args->list); 1206 } 1207 args->nalloc = args->num = 0; 1208 args->list = NULL; 1209 } 1210 1211 /* 1212 * Expands tildes in the file name. Returns data allocated by xmalloc. 1213 * Warning: this calls getpw*. 1214 */ 1215 int 1216 tilde_expand(const char *filename, uid_t uid, char **retp) 1217 { 1218 char *ocopy = NULL, *copy, *s = NULL; 1219 const char *path = NULL, *user = NULL; 1220 struct passwd *pw; 1221 size_t len; 1222 int ret = -1, r, slash; 1223 1224 *retp = NULL; 1225 if (*filename != '~') { 1226 *retp = xstrdup(filename); 1227 return 0; 1228 } 1229 ocopy = copy = xstrdup(filename + 1); 1230 1231 if (*copy == '\0') /* ~ */ 1232 path = NULL; 1233 else if (*copy == '/') { 1234 copy += strspn(copy, "/"); 1235 if (*copy == '\0') 1236 path = NULL; /* ~/ */ 1237 else 1238 path = copy; /* ~/path */ 1239 } else { 1240 user = copy; 1241 if ((path = strchr(copy, '/')) != NULL) { 1242 copy[path - copy] = '\0'; 1243 path++; 1244 path += strspn(path, "/"); 1245 if (*path == '\0') /* ~user/ */ 1246 path = NULL; 1247 /* else ~user/path */ 1248 } 1249 /* else ~user */ 1250 } 1251 if (user != NULL) { 1252 if ((pw = getpwnam(user)) == NULL) { 1253 error_f("No such user %s", user); 1254 goto out; 1255 } 1256 } else if ((pw = getpwuid(uid)) == NULL) { 1257 error_f("No such uid %ld", (long)uid); 1258 goto out; 1259 } 1260 1261 /* Make sure directory has a trailing '/' */ 1262 slash = (len = strlen(pw->pw_dir)) == 0 || pw->pw_dir[len - 1] != '/'; 1263 1264 if ((r = xasprintf(&s, "%s%s%s", pw->pw_dir, 1265 slash ? "/" : "", path != NULL ? path : "")) <= 0) { 1266 error_f("xasprintf failed"); 1267 goto out; 1268 } 1269 if (r >= PATH_MAX) { 1270 error_f("Path too long"); 1271 goto out; 1272 } 1273 /* success */ 1274 ret = 0; 1275 *retp = s; 1276 s = NULL; 1277 out: 1278 free(s); 1279 free(ocopy); 1280 return ret; 1281 } 1282 1283 char * 1284 tilde_expand_filename(const char *filename, uid_t uid) 1285 { 1286 char *ret; 1287 1288 if (tilde_expand(filename, uid, &ret) != 0) 1289 cleanup_exit(255); 1290 return ret; 1291 } 1292 1293 /* 1294 * Expand a string with a set of %[char] escapes and/or ${ENVIRONMENT} 1295 * substitutions. A number of escapes may be specified as 1296 * (char *escape_chars, char *replacement) pairs. The list must be terminated 1297 * by a NULL escape_char. Returns replaced string in memory allocated by 1298 * xmalloc which the caller must free. 1299 */ 1300 static char * 1301 vdollar_percent_expand(int *parseerror, int dollar, int percent, 1302 const char *string, va_list ap) 1303 { 1304 #define EXPAND_MAX_KEYS 64 1305 u_int num_keys = 0, i; 1306 struct { 1307 const char *key; 1308 const char *repl; 1309 } keys[EXPAND_MAX_KEYS]; 1310 struct sshbuf *buf; 1311 int r, missingvar = 0; 1312 char *ret = NULL, *var, *varend, *val; 1313 size_t len; 1314 1315 if ((buf = sshbuf_new()) == NULL) 1316 fatal_f("sshbuf_new failed"); 1317 if (parseerror == NULL) 1318 fatal_f("null parseerror arg"); 1319 *parseerror = 1; 1320 1321 /* Gather keys if we're doing percent expansion. */ 1322 if (percent) { 1323 for (num_keys = 0; num_keys < EXPAND_MAX_KEYS; num_keys++) { 1324 keys[num_keys].key = va_arg(ap, char *); 1325 if (keys[num_keys].key == NULL) 1326 break; 1327 keys[num_keys].repl = va_arg(ap, char *); 1328 if (keys[num_keys].repl == NULL) { 1329 fatal_f("NULL replacement for token %s", 1330 keys[num_keys].key); 1331 } 1332 } 1333 if (num_keys == EXPAND_MAX_KEYS && va_arg(ap, char *) != NULL) 1334 fatal_f("too many keys"); 1335 if (num_keys == 0) 1336 fatal_f("percent expansion without token list"); 1337 } 1338 1339 /* Expand string */ 1340 for (i = 0; *string != '\0'; string++) { 1341 /* Optionally process ${ENVIRONMENT} expansions. */ 1342 if (dollar && string[0] == '$' && string[1] == '{') { 1343 string += 2; /* skip over '${' */ 1344 if ((varend = strchr(string, '}')) == NULL) { 1345 error_f("environment variable '%s' missing " 1346 "closing '}'", string); 1347 goto out; 1348 } 1349 len = varend - string; 1350 if (len == 0) { 1351 error_f("zero-length environment variable"); 1352 goto out; 1353 } 1354 var = xmalloc(len + 1); 1355 (void)strlcpy(var, string, len + 1); 1356 if ((val = getenv(var)) == NULL) { 1357 error_f("env var ${%s} has no value", var); 1358 missingvar = 1; 1359 } else { 1360 debug3_f("expand ${%s} -> '%s'", var, val); 1361 if ((r = sshbuf_put(buf, val, strlen(val))) !=0) 1362 fatal_fr(r, "sshbuf_put ${}"); 1363 } 1364 free(var); 1365 string += len; 1366 continue; 1367 } 1368 1369 /* 1370 * Process percent expansions if we have a list of TOKENs. 1371 * If we're not doing percent expansion everything just gets 1372 * appended here. 1373 */ 1374 if (*string != '%' || !percent) { 1375 append: 1376 if ((r = sshbuf_put_u8(buf, *string)) != 0) 1377 fatal_fr(r, "sshbuf_put_u8 %%"); 1378 continue; 1379 } 1380 string++; 1381 /* %% case */ 1382 if (*string == '%') 1383 goto append; 1384 if (*string == '\0') { 1385 error_f("invalid format"); 1386 goto out; 1387 } 1388 for (i = 0; i < num_keys; i++) { 1389 if (strchr(keys[i].key, *string) != NULL) { 1390 if ((r = sshbuf_put(buf, keys[i].repl, 1391 strlen(keys[i].repl))) != 0) 1392 fatal_fr(r, "sshbuf_put %%-repl"); 1393 break; 1394 } 1395 } 1396 if (i >= num_keys) { 1397 error_f("unknown key %%%c", *string); 1398 goto out; 1399 } 1400 } 1401 if (!missingvar && (ret = sshbuf_dup_string(buf)) == NULL) 1402 fatal_f("sshbuf_dup_string failed"); 1403 *parseerror = 0; 1404 out: 1405 sshbuf_free(buf); 1406 return *parseerror ? NULL : ret; 1407 #undef EXPAND_MAX_KEYS 1408 } 1409 1410 /* 1411 * Expand only environment variables. 1412 * Note that although this function is variadic like the other similar 1413 * functions, any such arguments will be unused. 1414 */ 1415 1416 char * 1417 dollar_expand(int *parseerr, const char *string, ...) 1418 { 1419 char *ret; 1420 int err; 1421 va_list ap; 1422 1423 va_start(ap, string); 1424 ret = vdollar_percent_expand(&err, 1, 0, string, ap); 1425 va_end(ap); 1426 if (parseerr != NULL) 1427 *parseerr = err; 1428 return ret; 1429 } 1430 1431 /* 1432 * Returns expanded string or NULL if a specified environment variable is 1433 * not defined, or calls fatal if the string is invalid. 1434 */ 1435 char * 1436 percent_expand(const char *string, ...) 1437 { 1438 char *ret; 1439 int err; 1440 va_list ap; 1441 1442 va_start(ap, string); 1443 ret = vdollar_percent_expand(&err, 0, 1, string, ap); 1444 va_end(ap); 1445 if (err) 1446 fatal_f("failed"); 1447 return ret; 1448 } 1449 1450 /* 1451 * Returns expanded string or NULL if a specified environment variable is 1452 * not defined, or calls fatal if the string is invalid. 1453 */ 1454 char * 1455 percent_dollar_expand(const char *string, ...) 1456 { 1457 char *ret; 1458 int err; 1459 va_list ap; 1460 1461 va_start(ap, string); 1462 ret = vdollar_percent_expand(&err, 1, 1, string, ap); 1463 va_end(ap); 1464 if (err) 1465 fatal_f("failed"); 1466 return ret; 1467 } 1468 1469 int 1470 tun_open(int tun, int mode, char **ifname) 1471 { 1472 #if defined(CUSTOM_SYS_TUN_OPEN) 1473 return (sys_tun_open(tun, mode, ifname)); 1474 #elif defined(SSH_TUN_OPENBSD) 1475 struct ifreq ifr; 1476 char name[100]; 1477 int fd = -1, sock; 1478 const char *tunbase = "tun"; 1479 1480 if (ifname != NULL) 1481 *ifname = NULL; 1482 1483 if (mode == SSH_TUNMODE_ETHERNET) 1484 tunbase = "tap"; 1485 1486 /* Open the tunnel device */ 1487 if (tun <= SSH_TUNID_MAX) { 1488 snprintf(name, sizeof(name), "/dev/%s%d", tunbase, tun); 1489 fd = open(name, O_RDWR); 1490 } else if (tun == SSH_TUNID_ANY) { 1491 for (tun = 100; tun >= 0; tun--) { 1492 snprintf(name, sizeof(name), "/dev/%s%d", 1493 tunbase, tun); 1494 if ((fd = open(name, O_RDWR)) >= 0) 1495 break; 1496 } 1497 } else { 1498 debug_f("invalid tunnel %u", tun); 1499 return -1; 1500 } 1501 1502 if (fd == -1) { 1503 debug_f("%s open: %s", name, strerror(errno)); 1504 return -1; 1505 } 1506 1507 debug_f("%s mode %d fd %d", name, mode, fd); 1508 1509 /* Bring interface up if it is not already */ 1510 snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s%d", tunbase, tun); 1511 if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1) 1512 goto failed; 1513 1514 if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1) { 1515 debug_f("get interface %s flags: %s", ifr.ifr_name, 1516 strerror(errno)); 1517 goto failed; 1518 } 1519 1520 if (!(ifr.ifr_flags & IFF_UP)) { 1521 ifr.ifr_flags |= IFF_UP; 1522 if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1) { 1523 debug_f("activate interface %s: %s", ifr.ifr_name, 1524 strerror(errno)); 1525 goto failed; 1526 } 1527 } 1528 1529 if (ifname != NULL) 1530 *ifname = xstrdup(ifr.ifr_name); 1531 1532 close(sock); 1533 return fd; 1534 1535 failed: 1536 if (fd >= 0) 1537 close(fd); 1538 if (sock >= 0) 1539 close(sock); 1540 return -1; 1541 #else 1542 error("Tunnel interfaces are not supported on this platform"); 1543 return (-1); 1544 #endif 1545 } 1546 1547 void 1548 sanitise_stdfd(void) 1549 { 1550 int nullfd, dupfd; 1551 1552 if ((nullfd = dupfd = open(_PATH_DEVNULL, O_RDWR)) == -1) { 1553 fprintf(stderr, "Couldn't open /dev/null: %s\n", 1554 strerror(errno)); 1555 exit(1); 1556 } 1557 while (++dupfd <= STDERR_FILENO) { 1558 /* Only populate closed fds. */ 1559 if (fcntl(dupfd, F_GETFL) == -1 && errno == EBADF) { 1560 if (dup2(nullfd, dupfd) == -1) { 1561 fprintf(stderr, "dup2: %s\n", strerror(errno)); 1562 exit(1); 1563 } 1564 } 1565 } 1566 if (nullfd > STDERR_FILENO) 1567 close(nullfd); 1568 } 1569 1570 char * 1571 tohex(const void *vp, size_t l) 1572 { 1573 const u_char *p = (const u_char *)vp; 1574 char b[3], *r; 1575 size_t i, hl; 1576 1577 if (l > 65536) 1578 return xstrdup("tohex: length > 65536"); 1579 1580 hl = l * 2 + 1; 1581 r = xcalloc(1, hl); 1582 for (i = 0; i < l; i++) { 1583 snprintf(b, sizeof(b), "%02x", p[i]); 1584 strlcat(r, b, hl); 1585 } 1586 return (r); 1587 } 1588 1589 /* 1590 * Extend string *sp by the specified format. If *sp is not NULL (or empty), 1591 * then the separator 'sep' will be prepended before the formatted arguments. 1592 * Extended strings are heap allocated. 1593 */ 1594 void 1595 xextendf(char **sp, const char *sep, const char *fmt, ...) 1596 { 1597 va_list ap; 1598 char *tmp1, *tmp2; 1599 1600 va_start(ap, fmt); 1601 xvasprintf(&tmp1, fmt, ap); 1602 va_end(ap); 1603 1604 if (*sp == NULL || **sp == '\0') { 1605 free(*sp); 1606 *sp = tmp1; 1607 return; 1608 } 1609 xasprintf(&tmp2, "%s%s%s", *sp, sep == NULL ? "" : sep, tmp1); 1610 free(tmp1); 1611 free(*sp); 1612 *sp = tmp2; 1613 } 1614 1615 1616 u_int64_t 1617 get_u64(const void *vp) 1618 { 1619 const u_char *p = (const u_char *)vp; 1620 u_int64_t v; 1621 1622 v = (u_int64_t)p[0] << 56; 1623 v |= (u_int64_t)p[1] << 48; 1624 v |= (u_int64_t)p[2] << 40; 1625 v |= (u_int64_t)p[3] << 32; 1626 v |= (u_int64_t)p[4] << 24; 1627 v |= (u_int64_t)p[5] << 16; 1628 v |= (u_int64_t)p[6] << 8; 1629 v |= (u_int64_t)p[7]; 1630 1631 return (v); 1632 } 1633 1634 u_int32_t 1635 get_u32(const void *vp) 1636 { 1637 const u_char *p = (const u_char *)vp; 1638 u_int32_t v; 1639 1640 v = (u_int32_t)p[0] << 24; 1641 v |= (u_int32_t)p[1] << 16; 1642 v |= (u_int32_t)p[2] << 8; 1643 v |= (u_int32_t)p[3]; 1644 1645 return (v); 1646 } 1647 1648 u_int32_t 1649 get_u32_le(const void *vp) 1650 { 1651 const u_char *p = (const u_char *)vp; 1652 u_int32_t v; 1653 1654 v = (u_int32_t)p[0]; 1655 v |= (u_int32_t)p[1] << 8; 1656 v |= (u_int32_t)p[2] << 16; 1657 v |= (u_int32_t)p[3] << 24; 1658 1659 return (v); 1660 } 1661 1662 u_int16_t 1663 get_u16(const void *vp) 1664 { 1665 const u_char *p = (const u_char *)vp; 1666 u_int16_t v; 1667 1668 v = (u_int16_t)p[0] << 8; 1669 v |= (u_int16_t)p[1]; 1670 1671 return (v); 1672 } 1673 1674 void 1675 put_u64(void *vp, u_int64_t v) 1676 { 1677 u_char *p = (u_char *)vp; 1678 1679 p[0] = (u_char)(v >> 56) & 0xff; 1680 p[1] = (u_char)(v >> 48) & 0xff; 1681 p[2] = (u_char)(v >> 40) & 0xff; 1682 p[3] = (u_char)(v >> 32) & 0xff; 1683 p[4] = (u_char)(v >> 24) & 0xff; 1684 p[5] = (u_char)(v >> 16) & 0xff; 1685 p[6] = (u_char)(v >> 8) & 0xff; 1686 p[7] = (u_char)v & 0xff; 1687 } 1688 1689 void 1690 put_u32(void *vp, u_int32_t v) 1691 { 1692 u_char *p = (u_char *)vp; 1693 1694 p[0] = (u_char)(v >> 24) & 0xff; 1695 p[1] = (u_char)(v >> 16) & 0xff; 1696 p[2] = (u_char)(v >> 8) & 0xff; 1697 p[3] = (u_char)v & 0xff; 1698 } 1699 1700 void 1701 put_u32_le(void *vp, u_int32_t v) 1702 { 1703 u_char *p = (u_char *)vp; 1704 1705 p[0] = (u_char)v & 0xff; 1706 p[1] = (u_char)(v >> 8) & 0xff; 1707 p[2] = (u_char)(v >> 16) & 0xff; 1708 p[3] = (u_char)(v >> 24) & 0xff; 1709 } 1710 1711 void 1712 put_u16(void *vp, u_int16_t v) 1713 { 1714 u_char *p = (u_char *)vp; 1715 1716 p[0] = (u_char)(v >> 8) & 0xff; 1717 p[1] = (u_char)v & 0xff; 1718 } 1719 1720 void 1721 ms_subtract_diff(struct timeval *start, int *ms) 1722 { 1723 struct timeval diff, finish; 1724 1725 monotime_tv(&finish); 1726 timersub(&finish, start, &diff); 1727 *ms -= (diff.tv_sec * 1000) + (diff.tv_usec / 1000); 1728 } 1729 1730 void 1731 ms_to_timespec(struct timespec *ts, int ms) 1732 { 1733 if (ms < 0) 1734 ms = 0; 1735 ts->tv_sec = ms / 1000; 1736 ts->tv_nsec = (ms % 1000) * 1000 * 1000; 1737 } 1738 1739 void 1740 monotime_ts(struct timespec *ts) 1741 { 1742 struct timeval tv; 1743 #if defined(HAVE_CLOCK_GETTIME) && (defined(CLOCK_BOOTTIME) || \ 1744 defined(CLOCK_MONOTONIC) || defined(CLOCK_REALTIME)) 1745 static int gettime_failed = 0; 1746 1747 if (!gettime_failed) { 1748 # ifdef CLOCK_BOOTTIME 1749 if (clock_gettime(CLOCK_BOOTTIME, ts) == 0) 1750 return; 1751 # endif /* CLOCK_BOOTTIME */ 1752 # ifdef CLOCK_MONOTONIC 1753 if (clock_gettime(CLOCK_MONOTONIC, ts) == 0) 1754 return; 1755 # endif /* CLOCK_MONOTONIC */ 1756 # ifdef CLOCK_REALTIME 1757 /* Not monotonic, but we're almost out of options here. */ 1758 if (clock_gettime(CLOCK_REALTIME, ts) == 0) 1759 return; 1760 # endif /* CLOCK_REALTIME */ 1761 debug3("clock_gettime: %s", strerror(errno)); 1762 gettime_failed = 1; 1763 } 1764 #endif /* HAVE_CLOCK_GETTIME && (BOOTTIME || MONOTONIC || REALTIME) */ 1765 gettimeofday(&tv, NULL); 1766 ts->tv_sec = tv.tv_sec; 1767 ts->tv_nsec = (long)tv.tv_usec * 1000; 1768 } 1769 1770 void 1771 monotime_tv(struct timeval *tv) 1772 { 1773 struct timespec ts; 1774 1775 monotime_ts(&ts); 1776 tv->tv_sec = ts.tv_sec; 1777 tv->tv_usec = ts.tv_nsec / 1000; 1778 } 1779 1780 time_t 1781 monotime(void) 1782 { 1783 struct timespec ts; 1784 1785 monotime_ts(&ts); 1786 return ts.tv_sec; 1787 } 1788 1789 double 1790 monotime_double(void) 1791 { 1792 struct timespec ts; 1793 1794 monotime_ts(&ts); 1795 return ts.tv_sec + ((double)ts.tv_nsec / 1000000000); 1796 } 1797 1798 void 1799 bandwidth_limit_init(struct bwlimit *bw, u_int64_t kbps, size_t buflen) 1800 { 1801 bw->buflen = buflen; 1802 bw->rate = kbps; 1803 bw->thresh = buflen; 1804 bw->lamt = 0; 1805 timerclear(&bw->bwstart); 1806 timerclear(&bw->bwend); 1807 } 1808 1809 /* Callback from read/write loop to insert bandwidth-limiting delays */ 1810 void 1811 bandwidth_limit(struct bwlimit *bw, size_t read_len) 1812 { 1813 u_int64_t waitlen; 1814 struct timespec ts, rm; 1815 1816 bw->lamt += read_len; 1817 if (!timerisset(&bw->bwstart)) { 1818 monotime_tv(&bw->bwstart); 1819 return; 1820 } 1821 if (bw->lamt < bw->thresh) 1822 return; 1823 1824 monotime_tv(&bw->bwend); 1825 timersub(&bw->bwend, &bw->bwstart, &bw->bwend); 1826 if (!timerisset(&bw->bwend)) 1827 return; 1828 1829 bw->lamt *= 8; 1830 waitlen = (double)1000000L * bw->lamt / bw->rate; 1831 1832 bw->bwstart.tv_sec = waitlen / 1000000L; 1833 bw->bwstart.tv_usec = waitlen % 1000000L; 1834 1835 if (timercmp(&bw->bwstart, &bw->bwend, >)) { 1836 timersub(&bw->bwstart, &bw->bwend, &bw->bwend); 1837 1838 /* Adjust the wait time */ 1839 if (bw->bwend.tv_sec) { 1840 bw->thresh /= 2; 1841 if (bw->thresh < bw->buflen / 4) 1842 bw->thresh = bw->buflen / 4; 1843 } else if (bw->bwend.tv_usec < 10000) { 1844 bw->thresh *= 2; 1845 if (bw->thresh > bw->buflen * 8) 1846 bw->thresh = bw->buflen * 8; 1847 } 1848 1849 TIMEVAL_TO_TIMESPEC(&bw->bwend, &ts); 1850 while (nanosleep(&ts, &rm) == -1) { 1851 if (errno != EINTR) 1852 break; 1853 ts = rm; 1854 } 1855 } 1856 1857 bw->lamt = 0; 1858 monotime_tv(&bw->bwstart); 1859 } 1860 1861 /* Make a template filename for mk[sd]temp() */ 1862 void 1863 mktemp_proto(char *s, size_t len) 1864 { 1865 const char *tmpdir; 1866 int r; 1867 1868 if ((tmpdir = getenv("TMPDIR")) != NULL) { 1869 r = snprintf(s, len, "%s/ssh-XXXXXXXXXXXX", tmpdir); 1870 if (r > 0 && (size_t)r < len) 1871 return; 1872 } 1873 r = snprintf(s, len, "/tmp/ssh-XXXXXXXXXXXX"); 1874 if (r < 0 || (size_t)r >= len) 1875 fatal_f("template string too short"); 1876 } 1877 1878 static const struct { 1879 const char *name; 1880 int value; 1881 } ipqos[] = { 1882 { "none", INT_MAX }, /* can't use 0 here; that's CS0 */ 1883 { "af11", IPTOS_DSCP_AF11 }, 1884 { "af12", IPTOS_DSCP_AF12 }, 1885 { "af13", IPTOS_DSCP_AF13 }, 1886 { "af21", IPTOS_DSCP_AF21 }, 1887 { "af22", IPTOS_DSCP_AF22 }, 1888 { "af23", IPTOS_DSCP_AF23 }, 1889 { "af31", IPTOS_DSCP_AF31 }, 1890 { "af32", IPTOS_DSCP_AF32 }, 1891 { "af33", IPTOS_DSCP_AF33 }, 1892 { "af41", IPTOS_DSCP_AF41 }, 1893 { "af42", IPTOS_DSCP_AF42 }, 1894 { "af43", IPTOS_DSCP_AF43 }, 1895 { "cs0", IPTOS_DSCP_CS0 }, 1896 { "cs1", IPTOS_DSCP_CS1 }, 1897 { "cs2", IPTOS_DSCP_CS2 }, 1898 { "cs3", IPTOS_DSCP_CS3 }, 1899 { "cs4", IPTOS_DSCP_CS4 }, 1900 { "cs5", IPTOS_DSCP_CS5 }, 1901 { "cs6", IPTOS_DSCP_CS6 }, 1902 { "cs7", IPTOS_DSCP_CS7 }, 1903 { "ef", IPTOS_DSCP_EF }, 1904 { "le", IPTOS_DSCP_LE }, 1905 { "lowdelay", INT_MIN }, /* deprecated */ 1906 { "throughput", INT_MIN }, /* deprecated */ 1907 { "reliability", INT_MIN }, /* deprecated */ 1908 { NULL, -1 } 1909 }; 1910 1911 int 1912 parse_ipqos(const char *cp) 1913 { 1914 const char *errstr; 1915 u_int i; 1916 int val; 1917 1918 if (cp == NULL) 1919 return -1; 1920 for (i = 0; ipqos[i].name != NULL; i++) { 1921 if (strcasecmp(cp, ipqos[i].name) == 0) 1922 return ipqos[i].value; 1923 } 1924 /* Try parsing as an integer */ 1925 val = (int)strtonum(cp, 0, 255, &errstr); 1926 if (errstr) 1927 return -1; 1928 return val; 1929 } 1930 1931 const char * 1932 iptos2str(int iptos) 1933 { 1934 int i; 1935 static char iptos_str[sizeof "0xff"]; 1936 1937 for (i = 0; ipqos[i].name != NULL; i++) { 1938 if (ipqos[i].value == iptos) 1939 return ipqos[i].name; 1940 } 1941 snprintf(iptos_str, sizeof iptos_str, "0x%02x", iptos); 1942 return iptos_str; 1943 } 1944 1945 void 1946 lowercase(char *s) 1947 { 1948 for (; *s; s++) 1949 *s = tolower((u_char)*s); 1950 } 1951 1952 int 1953 unix_listener(const char *path, int backlog, int unlink_first) 1954 { 1955 struct sockaddr_un sunaddr; 1956 int saved_errno, sock; 1957 1958 memset(&sunaddr, 0, sizeof(sunaddr)); 1959 sunaddr.sun_family = AF_UNIX; 1960 if (strlcpy(sunaddr.sun_path, path, 1961 sizeof(sunaddr.sun_path)) >= sizeof(sunaddr.sun_path)) { 1962 error_f("path \"%s\" too long for Unix domain socket", path); 1963 errno = ENAMETOOLONG; 1964 return -1; 1965 } 1966 1967 sock = socket(PF_UNIX, SOCK_STREAM, 0); 1968 if (sock == -1) { 1969 saved_errno = errno; 1970 error_f("socket: %.100s", strerror(errno)); 1971 errno = saved_errno; 1972 return -1; 1973 } 1974 if (unlink_first == 1) { 1975 if (unlink(path) != 0 && errno != ENOENT) 1976 error("unlink(%s): %.100s", path, strerror(errno)); 1977 } 1978 if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) == -1) { 1979 saved_errno = errno; 1980 error_f("cannot bind to path %s: %s", path, strerror(errno)); 1981 close(sock); 1982 errno = saved_errno; 1983 return -1; 1984 } 1985 if (listen(sock, backlog) == -1) { 1986 saved_errno = errno; 1987 error_f("cannot listen on path %s: %s", path, strerror(errno)); 1988 close(sock); 1989 unlink(path); 1990 errno = saved_errno; 1991 return -1; 1992 } 1993 return sock; 1994 } 1995 1996 void 1997 sock_set_v6only(int s) 1998 { 1999 #if defined(IPV6_V6ONLY) && !defined(__OpenBSD__) 2000 int on = 1; 2001 2002 debug3_f("set socket %d IPV6_V6ONLY", s); 2003 if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) == -1) 2004 error("setsockopt IPV6_V6ONLY: %s", strerror(errno)); 2005 #endif 2006 } 2007 2008 /* 2009 * Compares two strings that maybe be NULL. Returns non-zero if strings 2010 * are both NULL or are identical, returns zero otherwise. 2011 */ 2012 static int 2013 strcmp_maybe_null(const char *a, const char *b) 2014 { 2015 if ((a == NULL && b != NULL) || (a != NULL && b == NULL)) 2016 return 0; 2017 if (a != NULL && strcmp(a, b) != 0) 2018 return 0; 2019 return 1; 2020 } 2021 2022 /* 2023 * Compare two forwards, returning non-zero if they are identical or 2024 * zero otherwise. 2025 */ 2026 int 2027 forward_equals(const struct Forward *a, const struct Forward *b) 2028 { 2029 if (strcmp_maybe_null(a->listen_host, b->listen_host) == 0) 2030 return 0; 2031 if (a->listen_port != b->listen_port) 2032 return 0; 2033 if (strcmp_maybe_null(a->listen_path, b->listen_path) == 0) 2034 return 0; 2035 if (strcmp_maybe_null(a->connect_host, b->connect_host) == 0) 2036 return 0; 2037 if (a->connect_port != b->connect_port) 2038 return 0; 2039 if (strcmp_maybe_null(a->connect_path, b->connect_path) == 0) 2040 return 0; 2041 /* allocated_port and handle are not checked */ 2042 return 1; 2043 } 2044 2045 /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */ 2046 int 2047 permitopen_port(const char *p) 2048 { 2049 int port; 2050 2051 if (strcmp(p, "*") == 0) 2052 return FWD_PERMIT_ANY_PORT; 2053 if ((port = a2port(p)) > 0) 2054 return port; 2055 return -1; 2056 } 2057 2058 /* returns 1 if process is already daemonized, 0 otherwise */ 2059 int 2060 daemonized(void) 2061 { 2062 int fd; 2063 2064 if ((fd = open(_PATH_TTY, O_RDONLY | O_NOCTTY)) >= 0) { 2065 close(fd); 2066 return 0; /* have controlling terminal */ 2067 } 2068 if (getppid() != 1) 2069 return 0; /* parent is not init */ 2070 if (getsid(0) != getpid()) 2071 return 0; /* not session leader */ 2072 debug3("already daemonized"); 2073 return 1; 2074 } 2075 2076 /* 2077 * Splits 's' into an argument vector. Handles quoted string and basic 2078 * escape characters (\\, \", \'). Caller must free the argument vector 2079 * and its members. 2080 */ 2081 int 2082 argv_split(const char *s, int *argcp, char ***argvp, int terminate_on_comment) 2083 { 2084 int r = SSH_ERR_INTERNAL_ERROR; 2085 int argc = 0, quote, i, j; 2086 char *arg, **argv = xcalloc(1, sizeof(*argv)); 2087 2088 *argvp = NULL; 2089 *argcp = 0; 2090 2091 for (i = 0; s[i] != '\0'; i++) { 2092 /* Skip leading whitespace */ 2093 if (s[i] == ' ' || s[i] == '\t') 2094 continue; 2095 if (terminate_on_comment && s[i] == '#') 2096 break; 2097 /* Start of a token */ 2098 quote = 0; 2099 2100 argv = xreallocarray(argv, (argc + 2), sizeof(*argv)); 2101 arg = argv[argc++] = xcalloc(1, strlen(s + i) + 1); 2102 argv[argc] = NULL; 2103 2104 /* Copy the token in, removing escapes */ 2105 for (j = 0; s[i] != '\0'; i++) { 2106 if (s[i] == '\\') { 2107 if (s[i + 1] == '\'' || 2108 s[i + 1] == '\"' || 2109 s[i + 1] == '\\' || 2110 (quote == 0 && s[i + 1] == ' ')) { 2111 i++; /* Skip '\' */ 2112 arg[j++] = s[i]; 2113 } else { 2114 /* Unrecognised escape */ 2115 arg[j++] = s[i]; 2116 } 2117 } else if (quote == 0 && (s[i] == ' ' || s[i] == '\t')) 2118 break; /* done */ 2119 else if (quote == 0 && (s[i] == '\"' || s[i] == '\'')) 2120 quote = s[i]; /* quote start */ 2121 else if (quote != 0 && s[i] == quote) 2122 quote = 0; /* quote end */ 2123 else 2124 arg[j++] = s[i]; 2125 } 2126 if (s[i] == '\0') { 2127 if (quote != 0) { 2128 /* Ran out of string looking for close quote */ 2129 r = SSH_ERR_INVALID_FORMAT; 2130 goto out; 2131 } 2132 break; 2133 } 2134 } 2135 /* Success */ 2136 *argcp = argc; 2137 *argvp = argv; 2138 argc = 0; 2139 argv = NULL; 2140 r = 0; 2141 out: 2142 if (argc != 0 && argv != NULL) { 2143 for (i = 0; i < argc; i++) 2144 free(argv[i]); 2145 free(argv); 2146 } 2147 return r; 2148 } 2149 2150 /* 2151 * Reassemble an argument vector into a string, quoting and escaping as 2152 * necessary. Caller must free returned string. 2153 */ 2154 char * 2155 argv_assemble(int argc, char **argv) 2156 { 2157 int i, j, ws, r; 2158 char c, *ret; 2159 struct sshbuf *buf, *arg; 2160 2161 if ((buf = sshbuf_new()) == NULL || (arg = sshbuf_new()) == NULL) 2162 fatal_f("sshbuf_new failed"); 2163 2164 for (i = 0; i < argc; i++) { 2165 ws = 0; 2166 sshbuf_reset(arg); 2167 for (j = 0; argv[i][j] != '\0'; j++) { 2168 r = 0; 2169 c = argv[i][j]; 2170 switch (c) { 2171 case ' ': 2172 case '\t': 2173 ws = 1; 2174 r = sshbuf_put_u8(arg, c); 2175 break; 2176 case '\\': 2177 case '\'': 2178 case '"': 2179 if ((r = sshbuf_put_u8(arg, '\\')) != 0) 2180 break; 2181 /* FALLTHROUGH */ 2182 default: 2183 r = sshbuf_put_u8(arg, c); 2184 break; 2185 } 2186 if (r != 0) 2187 fatal_fr(r, "sshbuf_put_u8"); 2188 } 2189 if ((i != 0 && (r = sshbuf_put_u8(buf, ' ')) != 0) || 2190 (ws != 0 && (r = sshbuf_put_u8(buf, '"')) != 0) || 2191 (r = sshbuf_putb(buf, arg)) != 0 || 2192 (ws != 0 && (r = sshbuf_put_u8(buf, '"')) != 0)) 2193 fatal_fr(r, "assemble"); 2194 } 2195 if ((ret = malloc(sshbuf_len(buf) + 1)) == NULL) 2196 fatal_f("malloc failed"); 2197 memcpy(ret, sshbuf_ptr(buf), sshbuf_len(buf)); 2198 ret[sshbuf_len(buf)] = '\0'; 2199 sshbuf_free(buf); 2200 sshbuf_free(arg); 2201 return ret; 2202 } 2203 2204 char * 2205 argv_next(int *argcp, char ***argvp) 2206 { 2207 char *ret = (*argvp)[0]; 2208 2209 if (*argcp > 0 && ret != NULL) { 2210 (*argcp)--; 2211 (*argvp)++; 2212 } 2213 return ret; 2214 } 2215 2216 void 2217 argv_consume(int *argcp) 2218 { 2219 *argcp = 0; 2220 } 2221 2222 void 2223 argv_free(char **av, int ac) 2224 { 2225 int i; 2226 2227 if (av == NULL) 2228 return; 2229 for (i = 0; i < ac; i++) 2230 free(av[i]); 2231 free(av); 2232 } 2233 2234 /* Returns 0 if pid exited cleanly, non-zero otherwise */ 2235 int 2236 exited_cleanly(pid_t pid, const char *tag, const char *cmd, int quiet) 2237 { 2238 int status; 2239 2240 while (waitpid(pid, &status, 0) == -1) { 2241 if (errno != EINTR) { 2242 error("%s waitpid: %s", tag, strerror(errno)); 2243 return -1; 2244 } 2245 } 2246 if (WIFSIGNALED(status)) { 2247 error("%s %s exited on signal %d", tag, cmd, WTERMSIG(status)); 2248 return -1; 2249 } else if (WEXITSTATUS(status) != 0) { 2250 do_log2(quiet ? SYSLOG_LEVEL_DEBUG1 : SYSLOG_LEVEL_INFO, 2251 "%s %s failed, status %d", tag, cmd, WEXITSTATUS(status)); 2252 return -1; 2253 } 2254 return 0; 2255 } 2256 2257 /* 2258 * Check a given path for security. This is defined as all components 2259 * of the path to the file must be owned by either the owner of 2260 * of the file or root and no directories must be group or world writable. 2261 * 2262 * XXX Should any specific check be done for sym links ? 2263 * 2264 * Takes a file name, its stat information (preferably from fstat() to 2265 * avoid races), the uid of the expected owner, their home directory and an 2266 * error buffer plus max size as arguments. 2267 * 2268 * Returns 0 on success and -1 on failure 2269 */ 2270 int 2271 safe_path(const char *name, struct stat *stp, const char *pw_dir, 2272 uid_t uid, char *err, size_t errlen) 2273 { 2274 char buf[PATH_MAX], buf2[PATH_MAX], homedir[PATH_MAX]; 2275 char *cp; 2276 int comparehome = 0; 2277 struct stat st; 2278 2279 if (realpath(name, buf) == NULL) { 2280 snprintf(err, errlen, "realpath %s failed: %s", name, 2281 strerror(errno)); 2282 return -1; 2283 } 2284 if (pw_dir != NULL && realpath(pw_dir, homedir) != NULL) 2285 comparehome = 1; 2286 2287 if (!S_ISREG(stp->st_mode)) { 2288 snprintf(err, errlen, "%s is not a regular file", buf); 2289 return -1; 2290 } 2291 if ((!platform_sys_dir_uid(stp->st_uid) && stp->st_uid != uid) || 2292 (stp->st_mode & 022) != 0) { 2293 snprintf(err, errlen, "bad ownership or modes for file %s", 2294 buf); 2295 return -1; 2296 } 2297 2298 /* for each component of the canonical path, walking upwards */ 2299 for (;;) { 2300 /* 2301 * POSIX allows dirname to modify its argument and return a 2302 * pointer into it, so make a copy to avoid overlapping strlcpy. 2303 */ 2304 strlcpy(buf2, buf, sizeof(buf2)); 2305 if ((cp = dirname(buf2)) == NULL) { 2306 snprintf(err, errlen, "dirname() failed"); 2307 return -1; 2308 } 2309 strlcpy(buf, cp, sizeof(buf)); 2310 2311 if (stat(buf, &st) == -1 || 2312 (!platform_sys_dir_uid(st.st_uid) && st.st_uid != uid) || 2313 (st.st_mode & 022) != 0) { 2314 snprintf(err, errlen, 2315 "bad ownership or modes for directory %s", buf); 2316 return -1; 2317 } 2318 2319 /* If are past the homedir then we can stop */ 2320 if (comparehome && strcmp(homedir, buf) == 0) 2321 break; 2322 2323 /* 2324 * dirname should always complete with a "/" path, 2325 * but we can be paranoid and check for "." too 2326 */ 2327 if ((strcmp("/", buf) == 0) || (strcmp(".", buf) == 0)) 2328 break; 2329 } 2330 return 0; 2331 } 2332 2333 /* 2334 * Version of safe_path() that accepts an open file descriptor to 2335 * avoid races. 2336 * 2337 * Returns 0 on success and -1 on failure 2338 */ 2339 int 2340 safe_path_fd(int fd, const char *file, struct passwd *pw, 2341 char *err, size_t errlen) 2342 { 2343 struct stat st; 2344 2345 /* check the open file to avoid races */ 2346 if (fstat(fd, &st) == -1) { 2347 snprintf(err, errlen, "cannot stat file %s: %s", 2348 file, strerror(errno)); 2349 return -1; 2350 } 2351 return safe_path(file, &st, pw->pw_dir, pw->pw_uid, err, errlen); 2352 } 2353 2354 /* 2355 * Sets the value of the given variable in the environment. If the variable 2356 * already exists, its value is overridden. 2357 */ 2358 void 2359 child_set_env(char ***envp, u_int *envsizep, const char *name, 2360 const char *value) 2361 { 2362 char **env; 2363 u_int envsize; 2364 u_int i, namelen; 2365 2366 if (strchr(name, '=') != NULL) { 2367 error("Invalid environment variable \"%.100s\"", name); 2368 return; 2369 } 2370 2371 /* 2372 * If we're passed an uninitialized list, allocate a single null 2373 * entry before continuing. 2374 */ 2375 if ((*envp == NULL) != (*envsizep == 0)) 2376 fatal_f("environment size mismatch"); 2377 if (*envp == NULL && *envsizep == 0) { 2378 *envp = xmalloc(sizeof(char *)); 2379 *envp[0] = NULL; 2380 *envsizep = 1; 2381 } 2382 2383 /* 2384 * Find the slot where the value should be stored. If the variable 2385 * already exists, we reuse the slot; otherwise we append a new slot 2386 * at the end of the array, expanding if necessary. 2387 */ 2388 env = *envp; 2389 namelen = strlen(name); 2390 for (i = 0; env[i]; i++) 2391 if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=') 2392 break; 2393 if (env[i]) { 2394 /* Reuse the slot. */ 2395 free(env[i]); 2396 } else { 2397 /* New variable. Expand if necessary. */ 2398 envsize = *envsizep; 2399 if (i >= envsize - 1) { 2400 if (envsize >= 1000) 2401 fatal("child_set_env: too many env vars"); 2402 envsize += 50; 2403 env = (*envp) = xreallocarray(env, envsize, sizeof(char *)); 2404 *envsizep = envsize; 2405 } 2406 /* Need to set the NULL pointer at end of array beyond the new slot. */ 2407 env[i + 1] = NULL; 2408 } 2409 2410 /* Allocate space and format the variable in the appropriate slot. */ 2411 /* XXX xasprintf */ 2412 env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1); 2413 snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value); 2414 } 2415 2416 /* 2417 * Check and optionally lowercase a domain name, also removes trailing '.' 2418 * Returns 1 on success and 0 on failure, storing an error message in errstr. 2419 */ 2420 int 2421 valid_domain(char *name, int makelower, const char **errstr) 2422 { 2423 size_t i, l = strlen(name); 2424 u_char c, last = '\0'; 2425 static char errbuf[256]; 2426 2427 if (l == 0) { 2428 strlcpy(errbuf, "empty domain name", sizeof(errbuf)); 2429 goto bad; 2430 } 2431 if (!isalpha((u_char)name[0]) && !isdigit((u_char)name[0]) && 2432 name[0] != '_' /* technically invalid, but common */) { 2433 snprintf(errbuf, sizeof(errbuf), "domain name \"%.100s\" " 2434 "starts with invalid character", name); 2435 goto bad; 2436 } 2437 for (i = 0; i < l; i++) { 2438 c = tolower((u_char)name[i]); 2439 if (makelower) 2440 name[i] = (char)c; 2441 if (last == '.' && c == '.') { 2442 snprintf(errbuf, sizeof(errbuf), "domain name " 2443 "\"%.100s\" contains consecutive separators", name); 2444 goto bad; 2445 } 2446 if (c != '.' && c != '-' && !isalnum(c) && 2447 c != '_') /* technically invalid, but common */ { 2448 snprintf(errbuf, sizeof(errbuf), "domain name " 2449 "\"%.100s\" contains invalid characters", name); 2450 goto bad; 2451 } 2452 last = c; 2453 } 2454 if (name[l - 1] == '.') 2455 name[l - 1] = '\0'; 2456 if (errstr != NULL) 2457 *errstr = NULL; 2458 return 1; 2459 bad: 2460 if (errstr != NULL) 2461 *errstr = errbuf; 2462 return 0; 2463 } 2464 2465 /* 2466 * Verify that a environment variable name (not including initial '$') is 2467 * valid; consisting of one or more alphanumeric or underscore characters only. 2468 * Returns 1 on valid, 0 otherwise. 2469 */ 2470 int 2471 valid_env_name(const char *name) 2472 { 2473 const char *cp; 2474 2475 if (name[0] == '\0') 2476 return 0; 2477 for (cp = name; *cp != '\0'; cp++) { 2478 if (!isalnum((u_char)*cp) && *cp != '_') 2479 return 0; 2480 } 2481 return 1; 2482 } 2483 2484 const char * 2485 atoi_err(const char *nptr, int *val) 2486 { 2487 const char *errstr = NULL; 2488 2489 if (nptr == NULL || *nptr == '\0') 2490 return "missing"; 2491 *val = strtonum(nptr, 0, INT_MAX, &errstr); 2492 return errstr; 2493 } 2494 2495 int 2496 parse_absolute_time(const char *s, uint64_t *tp) 2497 { 2498 struct tm tm; 2499 time_t tt; 2500 char buf[32], *fmt; 2501 const char *cp; 2502 size_t l; 2503 int is_utc = 0; 2504 2505 *tp = 0; 2506 2507 l = strlen(s); 2508 if (l > 1 && strcasecmp(s + l - 1, "Z") == 0) { 2509 is_utc = 1; 2510 l--; 2511 } else if (l > 3 && strcasecmp(s + l - 3, "UTC") == 0) { 2512 is_utc = 1; 2513 l -= 3; 2514 } 2515 /* 2516 * POSIX strptime says "The application shall ensure that there 2517 * is white-space or other non-alphanumeric characters between 2518 * any two conversion specifications" so arrange things this way. 2519 */ 2520 switch (l) { 2521 case 8: /* YYYYMMDD */ 2522 fmt = "%Y-%m-%d"; 2523 snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2s", s, s + 4, s + 6); 2524 break; 2525 case 12: /* YYYYMMDDHHMM */ 2526 fmt = "%Y-%m-%dT%H:%M"; 2527 snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2sT%.2s:%.2s", 2528 s, s + 4, s + 6, s + 8, s + 10); 2529 break; 2530 case 14: /* YYYYMMDDHHMMSS */ 2531 fmt = "%Y-%m-%dT%H:%M:%S"; 2532 snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2sT%.2s:%.2s:%.2s", 2533 s, s + 4, s + 6, s + 8, s + 10, s + 12); 2534 break; 2535 default: 2536 return SSH_ERR_INVALID_FORMAT; 2537 } 2538 2539 memset(&tm, 0, sizeof(tm)); 2540 if ((cp = strptime(buf, fmt, &tm)) == NULL || *cp != '\0') 2541 return SSH_ERR_INVALID_FORMAT; 2542 if (is_utc) { 2543 if ((tt = timegm(&tm)) < 0) 2544 return SSH_ERR_INVALID_FORMAT; 2545 } else { 2546 if ((tt = mktime(&tm)) < 0) 2547 return SSH_ERR_INVALID_FORMAT; 2548 } 2549 /* success */ 2550 *tp = (uint64_t)tt; 2551 return 0; 2552 } 2553 2554 void 2555 format_absolute_time(uint64_t t, char *buf, size_t len) 2556 { 2557 time_t tt = t > SSH_TIME_T_MAX ? SSH_TIME_T_MAX : t; 2558 struct tm tm; 2559 2560 if (localtime_r(&tt, &tm) == NULL) 2561 strlcpy(buf, "UNKNOWN-TIME", len); 2562 else 2563 strftime(buf, len, "%Y-%m-%dT%H:%M:%S", &tm); 2564 } 2565 2566 /* 2567 * Parse a "pattern=interval" clause (e.g. a ChannelTimeout). 2568 * Returns 0 on success or non-zero on failure. 2569 * Caller must free *typep. 2570 */ 2571 int 2572 parse_pattern_interval(const char *s, char **typep, int *secsp) 2573 { 2574 char *cp, *sdup; 2575 int secs; 2576 2577 if (typep != NULL) 2578 *typep = NULL; 2579 if (secsp != NULL) 2580 *secsp = 0; 2581 if (s == NULL) 2582 return -1; 2583 sdup = xstrdup(s); 2584 2585 if ((cp = strchr(sdup, '=')) == NULL || cp == sdup) { 2586 free(sdup); 2587 return -1; 2588 } 2589 *cp++ = '\0'; 2590 if ((secs = convtime(cp)) < 0) { 2591 free(sdup); 2592 return -1; 2593 } 2594 /* success */ 2595 if (typep != NULL) 2596 *typep = xstrdup(sdup); 2597 if (secsp != NULL) 2598 *secsp = secs; 2599 free(sdup); 2600 return 0; 2601 } 2602 2603 /* check if path is absolute */ 2604 int 2605 path_absolute(const char *path) 2606 { 2607 return (*path == '/') ? 1 : 0; 2608 } 2609 2610 void 2611 skip_space(char **cpp) 2612 { 2613 char *cp; 2614 2615 for (cp = *cpp; *cp == ' ' || *cp == '\t'; cp++) 2616 ; 2617 *cpp = cp; 2618 } 2619 2620 /* authorized_key-style options parsing helpers */ 2621 2622 /* 2623 * Match flag 'opt' in *optsp, and if allow_negate is set then also match 2624 * 'no-opt'. Returns -1 if option not matched, 1 if option matches or 0 2625 * if negated option matches. 2626 * If the option or negated option matches, then *optsp is updated to 2627 * point to the first character after the option. 2628 */ 2629 int 2630 opt_flag(const char *opt, int allow_negate, const char **optsp) 2631 { 2632 size_t opt_len = strlen(opt); 2633 const char *opts = *optsp; 2634 int negate = 0; 2635 2636 if (allow_negate && strncasecmp(opts, "no-", 3) == 0) { 2637 opts += 3; 2638 negate = 1; 2639 } 2640 if (strncasecmp(opts, opt, opt_len) == 0) { 2641 *optsp = opts + opt_len; 2642 return negate ? 0 : 1; 2643 } 2644 return -1; 2645 } 2646 2647 char * 2648 opt_dequote(const char **sp, const char **errstrp) 2649 { 2650 const char *s = *sp; 2651 char *ret; 2652 size_t i; 2653 2654 *errstrp = NULL; 2655 if (*s != '"') { 2656 *errstrp = "missing start quote"; 2657 return NULL; 2658 } 2659 s++; 2660 if ((ret = malloc(strlen((s)) + 1)) == NULL) { 2661 *errstrp = "memory allocation failed"; 2662 return NULL; 2663 } 2664 for (i = 0; *s != '\0' && *s != '"';) { 2665 if (s[0] == '\\' && s[1] == '"') 2666 s++; 2667 ret[i++] = *s++; 2668 } 2669 if (*s == '\0') { 2670 *errstrp = "missing end quote"; 2671 free(ret); 2672 return NULL; 2673 } 2674 ret[i] = '\0'; 2675 s++; 2676 *sp = s; 2677 return ret; 2678 } 2679 2680 int 2681 opt_match(const char **opts, const char *term) 2682 { 2683 if (strncasecmp((*opts), term, strlen(term)) == 0 && 2684 (*opts)[strlen(term)] == '=') { 2685 *opts += strlen(term) + 1; 2686 return 1; 2687 } 2688 return 0; 2689 } 2690 2691 void 2692 opt_array_append2(const char *file, const int line, const char *directive, 2693 char ***array, int **iarray, u_int *lp, const char *s, int i) 2694 { 2695 2696 if (*lp >= INT_MAX) 2697 fatal("%s line %d: Too many %s entries", file, line, directive); 2698 2699 if (iarray != NULL) { 2700 *iarray = xrecallocarray(*iarray, *lp, *lp + 1, 2701 sizeof(**iarray)); 2702 (*iarray)[*lp] = i; 2703 } 2704 2705 *array = xrecallocarray(*array, *lp, *lp + 1, sizeof(**array)); 2706 (*array)[*lp] = xstrdup(s); 2707 (*lp)++; 2708 } 2709 2710 void 2711 opt_array_append(const char *file, const int line, const char *directive, 2712 char ***array, u_int *lp, const char *s) 2713 { 2714 opt_array_append2(file, line, directive, array, NULL, lp, s, 0); 2715 } 2716 2717 void 2718 opt_array_free2(char **array, int **iarray, u_int l) 2719 { 2720 u_int i; 2721 2722 if (array == NULL || l == 0) 2723 return; 2724 for (i = 0; i < l; i++) 2725 free(array[i]); 2726 free(array); 2727 free(iarray); 2728 } 2729 2730 sshsig_t 2731 ssh_signal(int signum, sshsig_t handler) 2732 { 2733 struct sigaction sa, osa; 2734 2735 /* mask all other signals while in handler */ 2736 memset(&sa, 0, sizeof(sa)); 2737 sa.sa_handler = handler; 2738 sigfillset(&sa.sa_mask); 2739 #if defined(SA_RESTART) && !defined(NO_SA_RESTART) 2740 if (signum != SIGALRM) 2741 sa.sa_flags = SA_RESTART; 2742 #endif 2743 if (sigaction(signum, &sa, &osa) == -1) { 2744 debug3("sigaction(%s): %s", strsignal(signum), strerror(errno)); 2745 return SIG_ERR; 2746 } 2747 return osa.sa_handler; 2748 } 2749 2750 int 2751 stdfd_devnull(int do_stdin, int do_stdout, int do_stderr) 2752 { 2753 int devnull, ret = 0; 2754 2755 if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) { 2756 error_f("open %s: %s", _PATH_DEVNULL, 2757 strerror(errno)); 2758 return -1; 2759 } 2760 if ((do_stdin && dup2(devnull, STDIN_FILENO) == -1) || 2761 (do_stdout && dup2(devnull, STDOUT_FILENO) == -1) || 2762 (do_stderr && dup2(devnull, STDERR_FILENO) == -1)) { 2763 error_f("dup2: %s", strerror(errno)); 2764 ret = -1; 2765 } 2766 if (devnull > STDERR_FILENO) 2767 close(devnull); 2768 return ret; 2769 } 2770 2771 /* 2772 * Runs command in a subprocess with a minimal environment. 2773 * Returns pid on success, 0 on failure. 2774 * The child stdout and stderr maybe captured, left attached or sent to 2775 * /dev/null depending on the contents of flags. 2776 * "tag" is prepended to log messages. 2777 * NB. "command" is only used for logging; the actual command executed is 2778 * av[0]. 2779 */ 2780 pid_t 2781 subprocess(const char *tag, const char *command, 2782 int ac, char **av, FILE **child, u_int flags, 2783 struct passwd *pw, privdrop_fn *drop_privs, privrestore_fn *restore_privs) 2784 { 2785 FILE *f = NULL; 2786 struct stat st; 2787 int fd, devnull, p[2], i; 2788 pid_t pid; 2789 char *cp, errmsg[512]; 2790 u_int nenv = 0; 2791 char **env = NULL; 2792 2793 /* If dropping privs, then must specify user and restore function */ 2794 if (drop_privs != NULL && (pw == NULL || restore_privs == NULL)) { 2795 error("%s: inconsistent arguments", tag); /* XXX fatal? */ 2796 return 0; 2797 } 2798 if (pw == NULL && (pw = getpwuid(getuid())) == NULL) { 2799 error("%s: no user for current uid", tag); 2800 return 0; 2801 } 2802 if (child != NULL) 2803 *child = NULL; 2804 2805 debug3_f("%s command \"%s\" running as %s (flags 0x%x)", 2806 tag, command, pw->pw_name, flags); 2807 2808 /* Check consistency */ 2809 if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0 && 2810 (flags & SSH_SUBPROCESS_STDOUT_CAPTURE) != 0) { 2811 error_f("inconsistent flags"); 2812 return 0; 2813 } 2814 if (((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) == 0) != (child == NULL)) { 2815 error_f("inconsistent flags/output"); 2816 return 0; 2817 } 2818 2819 /* 2820 * If executing an explicit binary, then verify the it exists 2821 * and appears safe-ish to execute 2822 */ 2823 if (!path_absolute(av[0])) { 2824 error("%s path is not absolute", tag); 2825 return 0; 2826 } 2827 if (drop_privs != NULL) 2828 drop_privs(pw); 2829 if (stat(av[0], &st) == -1) { 2830 error("Could not stat %s \"%s\": %s", tag, 2831 av[0], strerror(errno)); 2832 goto restore_return; 2833 } 2834 if ((flags & SSH_SUBPROCESS_UNSAFE_PATH) == 0 && 2835 safe_path(av[0], &st, NULL, 0, errmsg, sizeof(errmsg)) != 0) { 2836 error("Unsafe %s \"%s\": %s", tag, av[0], errmsg); 2837 goto restore_return; 2838 } 2839 /* Prepare to keep the child's stdout if requested */ 2840 if (pipe(p) == -1) { 2841 error("%s: pipe: %s", tag, strerror(errno)); 2842 restore_return: 2843 if (restore_privs != NULL) 2844 restore_privs(); 2845 return 0; 2846 } 2847 if (restore_privs != NULL) 2848 restore_privs(); 2849 2850 switch ((pid = fork())) { 2851 case -1: /* error */ 2852 error("%s: fork: %s", tag, strerror(errno)); 2853 close(p[0]); 2854 close(p[1]); 2855 return 0; 2856 case 0: /* child */ 2857 /* Prepare a minimal environment for the child. */ 2858 if ((flags & SSH_SUBPROCESS_PRESERVE_ENV) == 0) { 2859 nenv = 5; 2860 env = xcalloc(sizeof(*env), nenv); 2861 child_set_env(&env, &nenv, "PATH", _PATH_STDPATH); 2862 child_set_env(&env, &nenv, "USER", pw->pw_name); 2863 child_set_env(&env, &nenv, "LOGNAME", pw->pw_name); 2864 child_set_env(&env, &nenv, "HOME", pw->pw_dir); 2865 if ((cp = getenv("LANG")) != NULL) 2866 child_set_env(&env, &nenv, "LANG", cp); 2867 } 2868 2869 for (i = 1; i < NSIG; i++) 2870 ssh_signal(i, SIG_DFL); 2871 2872 if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) { 2873 error("%s: open %s: %s", tag, _PATH_DEVNULL, 2874 strerror(errno)); 2875 _exit(1); 2876 } 2877 if (dup2(devnull, STDIN_FILENO) == -1) { 2878 error("%s: dup2: %s", tag, strerror(errno)); 2879 _exit(1); 2880 } 2881 2882 /* Set up stdout as requested; leave stderr in place for now. */ 2883 fd = -1; 2884 if ((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) != 0) 2885 fd = p[1]; 2886 else if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0) 2887 fd = devnull; 2888 if (fd != -1 && dup2(fd, STDOUT_FILENO) == -1) { 2889 error("%s: dup2: %s", tag, strerror(errno)); 2890 _exit(1); 2891 } 2892 closefrom(STDERR_FILENO + 1); 2893 2894 if (geteuid() == 0 && 2895 initgroups(pw->pw_name, pw->pw_gid) == -1) { 2896 error("%s: initgroups(%s, %u): %s", tag, 2897 pw->pw_name, (u_int)pw->pw_gid, strerror(errno)); 2898 _exit(1); 2899 } 2900 if (setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) == -1) { 2901 error("%s: setresgid %u: %s", tag, (u_int)pw->pw_gid, 2902 strerror(errno)); 2903 _exit(1); 2904 } 2905 if (setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid) == -1) { 2906 error("%s: setresuid %u: %s", tag, (u_int)pw->pw_uid, 2907 strerror(errno)); 2908 _exit(1); 2909 } 2910 /* stdin is pointed to /dev/null at this point */ 2911 if ((flags & SSH_SUBPROCESS_STDOUT_DISCARD) != 0 && 2912 dup2(STDIN_FILENO, STDERR_FILENO) == -1) { 2913 error("%s: dup2: %s", tag, strerror(errno)); 2914 _exit(1); 2915 } 2916 if (env != NULL) 2917 execve(av[0], av, env); 2918 else 2919 execv(av[0], av); 2920 error("%s %s \"%s\": %s", tag, env == NULL ? "execv" : "execve", 2921 command, strerror(errno)); 2922 _exit(127); 2923 default: /* parent */ 2924 break; 2925 } 2926 2927 close(p[1]); 2928 if ((flags & SSH_SUBPROCESS_STDOUT_CAPTURE) == 0) 2929 close(p[0]); 2930 else if ((f = fdopen(p[0], "r")) == NULL) { 2931 error("%s: fdopen: %s", tag, strerror(errno)); 2932 close(p[0]); 2933 /* Don't leave zombie child */ 2934 kill(pid, SIGTERM); 2935 while (waitpid(pid, NULL, 0) == -1 && errno == EINTR) 2936 ; 2937 return 0; 2938 } 2939 /* Success */ 2940 debug3_f("%s pid %ld", tag, (long)pid); 2941 if (child != NULL) 2942 *child = f; 2943 return pid; 2944 } 2945 2946 const char * 2947 lookup_env_in_list(const char *env, char * const *envs, size_t nenvs) 2948 { 2949 size_t i, envlen; 2950 2951 envlen = strlen(env); 2952 for (i = 0; i < nenvs; i++) { 2953 if (strncmp(envs[i], env, envlen) == 0 && 2954 envs[i][envlen] == '=') { 2955 return envs[i] + envlen + 1; 2956 } 2957 } 2958 return NULL; 2959 } 2960 2961 const char * 2962 lookup_setenv_in_list(const char *env, char * const *envs, size_t nenvs) 2963 { 2964 char *name, *cp; 2965 const char *ret; 2966 2967 name = xstrdup(env); 2968 if ((cp = strchr(name, '=')) == NULL) { 2969 free(name); 2970 return NULL; /* not env=val */ 2971 } 2972 *cp = '\0'; 2973 ret = lookup_env_in_list(name, envs, nenvs); 2974 free(name); 2975 return ret; 2976 } 2977 2978 /* 2979 * Helpers for managing poll(2)/ppoll(2) timeouts 2980 * Will remember the earliest deadline and return it for use in poll/ppoll. 2981 */ 2982 2983 /* Initialise a poll/ppoll timeout with an indefinite deadline */ 2984 void 2985 ptimeout_init(struct timespec *pt) 2986 { 2987 /* 2988 * Deliberately invalid for ppoll(2). 2989 * Will be converted to NULL in ptimeout_get_tspec() later. 2990 */ 2991 pt->tv_sec = -1; 2992 pt->tv_nsec = 0; 2993 } 2994 2995 /* Specify a poll/ppoll deadline of at most 'sec' seconds */ 2996 void 2997 ptimeout_deadline_sec(struct timespec *pt, long sec) 2998 { 2999 if (pt->tv_sec == -1 || pt->tv_sec >= sec) { 3000 pt->tv_sec = sec; 3001 pt->tv_nsec = 0; 3002 } 3003 } 3004 3005 /* Specify a poll/ppoll deadline of at most 'p' (timespec) */ 3006 static void 3007 ptimeout_deadline_tsp(struct timespec *pt, struct timespec *p) 3008 { 3009 if (pt->tv_sec == -1 || timespeccmp(pt, p, >=)) 3010 *pt = *p; 3011 } 3012 3013 /* Specify a poll/ppoll deadline of at most 'ms' milliseconds */ 3014 void 3015 ptimeout_deadline_ms(struct timespec *pt, long ms) 3016 { 3017 struct timespec p; 3018 3019 p.tv_sec = ms / 1000; 3020 p.tv_nsec = (ms % 1000) * 1000000; 3021 ptimeout_deadline_tsp(pt, &p); 3022 } 3023 3024 /* Specify a poll/ppoll deadline at wall clock monotime 'when' (timespec) */ 3025 void 3026 ptimeout_deadline_monotime_tsp(struct timespec *pt, struct timespec *when) 3027 { 3028 struct timespec now, t; 3029 3030 monotime_ts(&now); 3031 3032 if (timespeccmp(&now, when, >=)) { 3033 /* 'when' is now or in the past. Timeout ASAP */ 3034 pt->tv_sec = 0; 3035 pt->tv_nsec = 0; 3036 } else { 3037 timespecsub(when, &now, &t); 3038 ptimeout_deadline_tsp(pt, &t); 3039 } 3040 } 3041 3042 /* Specify a poll/ppoll deadline at wall clock monotime 'when' */ 3043 void 3044 ptimeout_deadline_monotime(struct timespec *pt, time_t when) 3045 { 3046 struct timespec t; 3047 3048 t.tv_sec = when; 3049 t.tv_nsec = 0; 3050 ptimeout_deadline_monotime_tsp(pt, &t); 3051 } 3052 3053 /* Get a poll(2) timeout value in milliseconds */ 3054 int 3055 ptimeout_get_ms(struct timespec *pt) 3056 { 3057 if (pt->tv_sec == -1) 3058 return -1; 3059 if (pt->tv_sec >= (INT_MAX - (pt->tv_nsec / 1000000)) / 1000) 3060 return INT_MAX; 3061 return (pt->tv_sec * 1000) + (pt->tv_nsec / 1000000); 3062 } 3063 3064 /* Get a ppoll(2) timeout value as a timespec pointer */ 3065 struct timespec * 3066 ptimeout_get_tsp(struct timespec *pt) 3067 { 3068 return pt->tv_sec == -1 ? NULL : pt; 3069 } 3070 3071 /* Returns non-zero if a timeout has been set (i.e. is not indefinite) */ 3072 int 3073 ptimeout_isset(struct timespec *pt) 3074 { 3075 return pt->tv_sec != -1; 3076 } 3077 3078 /* 3079 * Returns zero if the library at 'path' contains symbol 's', nonzero 3080 * otherwise. 3081 */ 3082 int 3083 lib_contains_symbol(const char *path, const char *s) 3084 { 3085 #ifdef HAVE_NLIST 3086 struct nlist nl[2]; 3087 int ret = -1, r; 3088 3089 memset(nl, 0, sizeof(nl)); 3090 nl[0].n_name = xstrdup(s); 3091 nl[1].n_name = NULL; 3092 if ((r = nlist(path, nl)) == -1) { 3093 error_f("nlist failed for %s", path); 3094 goto out; 3095 } 3096 if (r != 0 || nl[0].n_value == 0 || nl[0].n_type == 0) { 3097 error_f("library %s does not contain symbol %s", path, s); 3098 goto out; 3099 } 3100 /* success */ 3101 ret = 0; 3102 out: 3103 free(nl[0].n_name); 3104 return ret; 3105 #else /* HAVE_NLIST */ 3106 int fd, ret = -1; 3107 struct stat st; 3108 void *m = NULL; 3109 size_t sz = 0; 3110 3111 memset(&st, 0, sizeof(st)); 3112 if ((fd = open(path, O_RDONLY)) < 0) { 3113 error_f("open %s: %s", path, strerror(errno)); 3114 return -1; 3115 } 3116 if (fstat(fd, &st) != 0) { 3117 error_f("fstat %s: %s", path, strerror(errno)); 3118 goto out; 3119 } 3120 if (!S_ISREG(st.st_mode)) { 3121 error_f("%s is not a regular file", path); 3122 goto out; 3123 } 3124 if (st.st_size < 0 || 3125 (size_t)st.st_size < strlen(s) || 3126 st.st_size >= INT_MAX/2) { 3127 error_f("%s bad size %lld", path, (long long)st.st_size); 3128 goto out; 3129 } 3130 sz = (size_t)st.st_size; 3131 if ((m = mmap(NULL, sz, PROT_READ, MAP_PRIVATE, fd, 0)) == MAP_FAILED || 3132 m == NULL) { 3133 error_f("mmap %s: %s", path, strerror(errno)); 3134 goto out; 3135 } 3136 if (memmem(m, sz, s, strlen(s)) == NULL) { 3137 error_f("%s does not contain expected string %s", path, s); 3138 goto out; 3139 } 3140 /* success */ 3141 ret = 0; 3142 out: 3143 if (m != NULL && m != MAP_FAILED) 3144 munmap(m, sz); 3145 close(fd); 3146 return ret; 3147 #endif /* HAVE_NLIST */ 3148 } 3149 3150 int 3151 signal_is_crash(int sig) 3152 { 3153 switch (sig) { 3154 case SIGSEGV: 3155 case SIGBUS: 3156 case SIGTRAP: 3157 case SIGSYS: 3158 case SIGFPE: 3159 case SIGILL: 3160 case SIGABRT: 3161 return 1; 3162 } 3163 return 0; 3164 } 3165 3166 char * 3167 get_homedir(void) 3168 { 3169 char *cp; 3170 struct passwd *pw; 3171 3172 if ((cp = getenv("HOME")) != NULL && *cp != '\0') 3173 return xstrdup(cp); 3174 3175 if ((pw = getpwuid(getuid())) != NULL && *pw->pw_dir != '\0') 3176 return xstrdup(pw->pw_dir); 3177 3178 return NULL; 3179 } 3180