1 /* $OpenBSD: misc.c,v 1.109 2017/03/14 00:55:37 dtucker Exp $ */ 2 /* 3 * Copyright (c) 2000 Markus Friedl. All rights reserved. 4 * Copyright (c) 2005,2006 Damien Miller. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include "includes.h" 28 29 #include <sys/types.h> 30 #include <sys/ioctl.h> 31 #include <sys/socket.h> 32 #include <sys/time.h> 33 #include <sys/un.h> 34 35 #include <limits.h> 36 #include <stdarg.h> 37 #include <stdio.h> 38 #include <stdlib.h> 39 #include <string.h> 40 #include <time.h> 41 #include <unistd.h> 42 43 #include <netinet/in.h> 44 #include <netinet/in_systm.h> 45 #include <netinet/ip.h> 46 #include <netinet/tcp.h> 47 48 #include <ctype.h> 49 #include <errno.h> 50 #include <fcntl.h> 51 #include <netdb.h> 52 #ifdef HAVE_PATHS_H 53 # include <paths.h> 54 #include <pwd.h> 55 #endif 56 #ifdef SSH_TUN_OPENBSD 57 #include <net/if.h> 58 #endif 59 60 #include "xmalloc.h" 61 #include "misc.h" 62 #include "log.h" 63 #include "ssh.h" 64 65 /* remove newline at end of string */ 66 char * 67 chop(char *s) 68 { 69 char *t = s; 70 while (*t) { 71 if (*t == '\n' || *t == '\r') { 72 *t = '\0'; 73 return s; 74 } 75 t++; 76 } 77 return s; 78 79 } 80 81 /* set/unset filedescriptor to non-blocking */ 82 int 83 set_nonblock(int fd) 84 { 85 int val; 86 87 val = fcntl(fd, F_GETFL); 88 if (val < 0) { 89 error("fcntl(%d, F_GETFL): %s", fd, strerror(errno)); 90 return (-1); 91 } 92 if (val & O_NONBLOCK) { 93 debug3("fd %d is O_NONBLOCK", fd); 94 return (0); 95 } 96 debug2("fd %d setting O_NONBLOCK", fd); 97 val |= O_NONBLOCK; 98 if (fcntl(fd, F_SETFL, val) == -1) { 99 debug("fcntl(%d, F_SETFL, O_NONBLOCK): %s", fd, 100 strerror(errno)); 101 return (-1); 102 } 103 return (0); 104 } 105 106 int 107 unset_nonblock(int fd) 108 { 109 int val; 110 111 val = fcntl(fd, F_GETFL); 112 if (val < 0) { 113 error("fcntl(%d, F_GETFL): %s", fd, strerror(errno)); 114 return (-1); 115 } 116 if (!(val & O_NONBLOCK)) { 117 debug3("fd %d is not O_NONBLOCK", fd); 118 return (0); 119 } 120 debug("fd %d clearing O_NONBLOCK", fd); 121 val &= ~O_NONBLOCK; 122 if (fcntl(fd, F_SETFL, val) == -1) { 123 debug("fcntl(%d, F_SETFL, ~O_NONBLOCK): %s", 124 fd, strerror(errno)); 125 return (-1); 126 } 127 return (0); 128 } 129 130 const char * 131 ssh_gai_strerror(int gaierr) 132 { 133 if (gaierr == EAI_SYSTEM && errno != 0) 134 return strerror(errno); 135 return gai_strerror(gaierr); 136 } 137 138 /* disable nagle on socket */ 139 void 140 set_nodelay(int fd) 141 { 142 int opt; 143 socklen_t optlen; 144 145 optlen = sizeof opt; 146 if (getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, &optlen) == -1) { 147 debug("getsockopt TCP_NODELAY: %.100s", strerror(errno)); 148 return; 149 } 150 if (opt == 1) { 151 debug2("fd %d is TCP_NODELAY", fd); 152 return; 153 } 154 opt = 1; 155 debug2("fd %d setting TCP_NODELAY", fd); 156 if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof opt) == -1) 157 error("setsockopt TCP_NODELAY: %.100s", strerror(errno)); 158 } 159 160 /* Characters considered whitespace in strsep calls. */ 161 #define WHITESPACE " \t\r\n" 162 #define QUOTE "\"" 163 164 /* return next token in configuration line */ 165 char * 166 strdelim(char **s) 167 { 168 char *old; 169 int wspace = 0; 170 171 if (*s == NULL) 172 return NULL; 173 174 old = *s; 175 176 *s = strpbrk(*s, WHITESPACE QUOTE "="); 177 if (*s == NULL) 178 return (old); 179 180 if (*s[0] == '\"') { 181 memmove(*s, *s + 1, strlen(*s)); /* move nul too */ 182 /* Find matching quote */ 183 if ((*s = strpbrk(*s, QUOTE)) == NULL) { 184 return (NULL); /* no matching quote */ 185 } else { 186 *s[0] = '\0'; 187 *s += strspn(*s + 1, WHITESPACE) + 1; 188 return (old); 189 } 190 } 191 192 /* Allow only one '=' to be skipped */ 193 if (*s[0] == '=') 194 wspace = 1; 195 *s[0] = '\0'; 196 197 /* Skip any extra whitespace after first token */ 198 *s += strspn(*s + 1, WHITESPACE) + 1; 199 if (*s[0] == '=' && !wspace) 200 *s += strspn(*s + 1, WHITESPACE) + 1; 201 202 return (old); 203 } 204 205 struct passwd * 206 pwcopy(struct passwd *pw) 207 { 208 struct passwd *copy = xcalloc(1, sizeof(*copy)); 209 210 copy->pw_name = xstrdup(pw->pw_name); 211 copy->pw_passwd = xstrdup(pw->pw_passwd); 212 #ifdef HAVE_STRUCT_PASSWD_PW_GECOS 213 copy->pw_gecos = xstrdup(pw->pw_gecos); 214 #endif 215 copy->pw_uid = pw->pw_uid; 216 copy->pw_gid = pw->pw_gid; 217 #ifdef HAVE_STRUCT_PASSWD_PW_EXPIRE 218 copy->pw_expire = pw->pw_expire; 219 #endif 220 #ifdef HAVE_STRUCT_PASSWD_PW_CHANGE 221 copy->pw_change = pw->pw_change; 222 #endif 223 #ifdef HAVE_STRUCT_PASSWD_PW_CLASS 224 copy->pw_class = xstrdup(pw->pw_class); 225 #endif 226 copy->pw_dir = xstrdup(pw->pw_dir); 227 copy->pw_shell = xstrdup(pw->pw_shell); 228 return copy; 229 } 230 231 /* 232 * Convert ASCII string to TCP/IP port number. 233 * Port must be >=0 and <=65535. 234 * Return -1 if invalid. 235 */ 236 int 237 a2port(const char *s) 238 { 239 long long port; 240 const char *errstr; 241 242 port = strtonum(s, 0, 65535, &errstr); 243 if (errstr != NULL) 244 return -1; 245 return (int)port; 246 } 247 248 int 249 a2tun(const char *s, int *remote) 250 { 251 const char *errstr = NULL; 252 char *sp, *ep; 253 int tun; 254 255 if (remote != NULL) { 256 *remote = SSH_TUNID_ANY; 257 sp = xstrdup(s); 258 if ((ep = strchr(sp, ':')) == NULL) { 259 free(sp); 260 return (a2tun(s, NULL)); 261 } 262 ep[0] = '\0'; ep++; 263 *remote = a2tun(ep, NULL); 264 tun = a2tun(sp, NULL); 265 free(sp); 266 return (*remote == SSH_TUNID_ERR ? *remote : tun); 267 } 268 269 if (strcasecmp(s, "any") == 0) 270 return (SSH_TUNID_ANY); 271 272 tun = strtonum(s, 0, SSH_TUNID_MAX, &errstr); 273 if (errstr != NULL) 274 return (SSH_TUNID_ERR); 275 276 return (tun); 277 } 278 279 #define SECONDS 1 280 #define MINUTES (SECONDS * 60) 281 #define HOURS (MINUTES * 60) 282 #define DAYS (HOURS * 24) 283 #define WEEKS (DAYS * 7) 284 285 /* 286 * Convert a time string into seconds; format is 287 * a sequence of: 288 * time[qualifier] 289 * 290 * Valid time qualifiers are: 291 * <none> seconds 292 * s|S seconds 293 * m|M minutes 294 * h|H hours 295 * d|D days 296 * w|W weeks 297 * 298 * Examples: 299 * 90m 90 minutes 300 * 1h30m 90 minutes 301 * 2d 2 days 302 * 1w 1 week 303 * 304 * Return -1 if time string is invalid. 305 */ 306 long 307 convtime(const char *s) 308 { 309 long total, secs, multiplier = 1; 310 const char *p; 311 char *endp; 312 313 errno = 0; 314 total = 0; 315 p = s; 316 317 if (p == NULL || *p == '\0') 318 return -1; 319 320 while (*p) { 321 secs = strtol(p, &endp, 10); 322 if (p == endp || 323 (errno == ERANGE && (secs == LONG_MIN || secs == LONG_MAX)) || 324 secs < 0) 325 return -1; 326 327 switch (*endp++) { 328 case '\0': 329 endp--; 330 break; 331 case 's': 332 case 'S': 333 break; 334 case 'm': 335 case 'M': 336 multiplier = MINUTES; 337 break; 338 case 'h': 339 case 'H': 340 multiplier = HOURS; 341 break; 342 case 'd': 343 case 'D': 344 multiplier = DAYS; 345 break; 346 case 'w': 347 case 'W': 348 multiplier = WEEKS; 349 break; 350 default: 351 return -1; 352 } 353 if (secs >= LONG_MAX / multiplier) 354 return -1; 355 secs *= multiplier; 356 if (total >= LONG_MAX - secs) 357 return -1; 358 total += secs; 359 if (total < 0) 360 return -1; 361 p = endp; 362 } 363 364 return total; 365 } 366 367 /* 368 * Returns a standardized host+port identifier string. 369 * Caller must free returned string. 370 */ 371 char * 372 put_host_port(const char *host, u_short port) 373 { 374 char *hoststr; 375 376 if (port == 0 || port == SSH_DEFAULT_PORT) 377 return(xstrdup(host)); 378 if (asprintf(&hoststr, "[%s]:%d", host, (int)port) < 0) 379 fatal("put_host_port: asprintf: %s", strerror(errno)); 380 debug3("put_host_port: %s", hoststr); 381 return hoststr; 382 } 383 384 /* 385 * Search for next delimiter between hostnames/addresses and ports. 386 * Argument may be modified (for termination). 387 * Returns *cp if parsing succeeds. 388 * *cp is set to the start of the next delimiter, if one was found. 389 * If this is the last field, *cp is set to NULL. 390 */ 391 char * 392 hpdelim(char **cp) 393 { 394 char *s, *old; 395 396 if (cp == NULL || *cp == NULL) 397 return NULL; 398 399 old = s = *cp; 400 if (*s == '[') { 401 if ((s = strchr(s, ']')) == NULL) 402 return NULL; 403 else 404 s++; 405 } else if ((s = strpbrk(s, ":/")) == NULL) 406 s = *cp + strlen(*cp); /* skip to end (see first case below) */ 407 408 switch (*s) { 409 case '\0': 410 *cp = NULL; /* no more fields*/ 411 break; 412 413 case ':': 414 case '/': 415 *s = '\0'; /* terminate */ 416 *cp = s + 1; 417 break; 418 419 default: 420 return NULL; 421 } 422 423 return old; 424 } 425 426 char * 427 cleanhostname(char *host) 428 { 429 if (*host == '[' && host[strlen(host) - 1] == ']') { 430 host[strlen(host) - 1] = '\0'; 431 return (host + 1); 432 } else 433 return host; 434 } 435 436 char * 437 colon(char *cp) 438 { 439 int flag = 0; 440 441 if (*cp == ':') /* Leading colon is part of file name. */ 442 return NULL; 443 if (*cp == '[') 444 flag = 1; 445 446 for (; *cp; ++cp) { 447 if (*cp == '@' && *(cp+1) == '[') 448 flag = 1; 449 if (*cp == ']' && *(cp+1) == ':' && flag) 450 return (cp+1); 451 if (*cp == ':' && !flag) 452 return (cp); 453 if (*cp == '/') 454 return NULL; 455 } 456 return NULL; 457 } 458 459 /* 460 * Parse a [user@]host[:port] string. 461 * Caller must free returned user and host. 462 * Any of the pointer return arguments may be NULL (useful for syntax checking). 463 * If user was not specified then *userp will be set to NULL. 464 * If port was not specified then *portp will be -1. 465 * Returns 0 on success, -1 on failure. 466 */ 467 int 468 parse_user_host_port(const char *s, char **userp, char **hostp, int *portp) 469 { 470 char *sdup, *cp, *tmp; 471 char *user = NULL, *host = NULL; 472 int port = -1, ret = -1; 473 474 if (userp != NULL) 475 *userp = NULL; 476 if (hostp != NULL) 477 *hostp = NULL; 478 if (portp != NULL) 479 *portp = -1; 480 481 if ((sdup = tmp = strdup(s)) == NULL) 482 return -1; 483 /* Extract optional username */ 484 if ((cp = strchr(tmp, '@')) != NULL) { 485 *cp = '\0'; 486 if (*tmp == '\0') 487 goto out; 488 if ((user = strdup(tmp)) == NULL) 489 goto out; 490 tmp = cp + 1; 491 } 492 /* Extract mandatory hostname */ 493 if ((cp = hpdelim(&tmp)) == NULL || *cp == '\0') 494 goto out; 495 host = xstrdup(cleanhostname(cp)); 496 /* Convert and verify optional port */ 497 if (tmp != NULL && *tmp != '\0') { 498 if ((port = a2port(tmp)) <= 0) 499 goto out; 500 } 501 /* Success */ 502 if (userp != NULL) { 503 *userp = user; 504 user = NULL; 505 } 506 if (hostp != NULL) { 507 *hostp = host; 508 host = NULL; 509 } 510 if (portp != NULL) 511 *portp = port; 512 ret = 0; 513 out: 514 free(sdup); 515 free(user); 516 free(host); 517 return ret; 518 } 519 520 /* function to assist building execv() arguments */ 521 void 522 addargs(arglist *args, char *fmt, ...) 523 { 524 va_list ap; 525 char *cp; 526 u_int nalloc; 527 int r; 528 529 va_start(ap, fmt); 530 r = vasprintf(&cp, fmt, ap); 531 va_end(ap); 532 if (r == -1) 533 fatal("addargs: argument too long"); 534 535 nalloc = args->nalloc; 536 if (args->list == NULL) { 537 nalloc = 32; 538 args->num = 0; 539 } else if (args->num+2 >= nalloc) 540 nalloc *= 2; 541 542 args->list = xreallocarray(args->list, nalloc, sizeof(char *)); 543 args->nalloc = nalloc; 544 args->list[args->num++] = cp; 545 args->list[args->num] = NULL; 546 } 547 548 void 549 replacearg(arglist *args, u_int which, char *fmt, ...) 550 { 551 va_list ap; 552 char *cp; 553 int r; 554 555 va_start(ap, fmt); 556 r = vasprintf(&cp, fmt, ap); 557 va_end(ap); 558 if (r == -1) 559 fatal("replacearg: argument too long"); 560 561 if (which >= args->num) 562 fatal("replacearg: tried to replace invalid arg %d >= %d", 563 which, args->num); 564 free(args->list[which]); 565 args->list[which] = cp; 566 } 567 568 void 569 freeargs(arglist *args) 570 { 571 u_int i; 572 573 if (args->list != NULL) { 574 for (i = 0; i < args->num; i++) 575 free(args->list[i]); 576 free(args->list); 577 args->nalloc = args->num = 0; 578 args->list = NULL; 579 } 580 } 581 582 /* 583 * Expands tildes in the file name. Returns data allocated by xmalloc. 584 * Warning: this calls getpw*. 585 */ 586 char * 587 tilde_expand_filename(const char *filename, uid_t uid) 588 { 589 const char *path, *sep; 590 char user[128], *ret; 591 struct passwd *pw; 592 u_int len, slash; 593 594 if (*filename != '~') 595 return (xstrdup(filename)); 596 filename++; 597 598 path = strchr(filename, '/'); 599 if (path != NULL && path > filename) { /* ~user/path */ 600 slash = path - filename; 601 if (slash > sizeof(user) - 1) 602 fatal("tilde_expand_filename: ~username too long"); 603 memcpy(user, filename, slash); 604 user[slash] = '\0'; 605 if ((pw = getpwnam(user)) == NULL) 606 fatal("tilde_expand_filename: No such user %s", user); 607 } else if ((pw = getpwuid(uid)) == NULL) /* ~/path */ 608 fatal("tilde_expand_filename: No such uid %ld", (long)uid); 609 610 /* Make sure directory has a trailing '/' */ 611 len = strlen(pw->pw_dir); 612 if (len == 0 || pw->pw_dir[len - 1] != '/') 613 sep = "/"; 614 else 615 sep = ""; 616 617 /* Skip leading '/' from specified path */ 618 if (path != NULL) 619 filename = path + 1; 620 621 if (xasprintf(&ret, "%s%s%s", pw->pw_dir, sep, filename) >= PATH_MAX) 622 fatal("tilde_expand_filename: Path too long"); 623 624 return (ret); 625 } 626 627 /* 628 * Expand a string with a set of %[char] escapes. A number of escapes may be 629 * specified as (char *escape_chars, char *replacement) pairs. The list must 630 * be terminated by a NULL escape_char. Returns replaced string in memory 631 * allocated by xmalloc. 632 */ 633 char * 634 percent_expand(const char *string, ...) 635 { 636 #define EXPAND_MAX_KEYS 16 637 u_int num_keys, i, j; 638 struct { 639 const char *key; 640 const char *repl; 641 } keys[EXPAND_MAX_KEYS]; 642 char buf[4096]; 643 va_list ap; 644 645 /* Gather keys */ 646 va_start(ap, string); 647 for (num_keys = 0; num_keys < EXPAND_MAX_KEYS; num_keys++) { 648 keys[num_keys].key = va_arg(ap, char *); 649 if (keys[num_keys].key == NULL) 650 break; 651 keys[num_keys].repl = va_arg(ap, char *); 652 if (keys[num_keys].repl == NULL) 653 fatal("%s: NULL replacement", __func__); 654 } 655 if (num_keys == EXPAND_MAX_KEYS && va_arg(ap, char *) != NULL) 656 fatal("%s: too many keys", __func__); 657 va_end(ap); 658 659 /* Expand string */ 660 *buf = '\0'; 661 for (i = 0; *string != '\0'; string++) { 662 if (*string != '%') { 663 append: 664 buf[i++] = *string; 665 if (i >= sizeof(buf)) 666 fatal("%s: string too long", __func__); 667 buf[i] = '\0'; 668 continue; 669 } 670 string++; 671 /* %% case */ 672 if (*string == '%') 673 goto append; 674 if (*string == '\0') 675 fatal("%s: invalid format", __func__); 676 for (j = 0; j < num_keys; j++) { 677 if (strchr(keys[j].key, *string) != NULL) { 678 i = strlcat(buf, keys[j].repl, sizeof(buf)); 679 if (i >= sizeof(buf)) 680 fatal("%s: string too long", __func__); 681 break; 682 } 683 } 684 if (j >= num_keys) 685 fatal("%s: unknown key %%%c", __func__, *string); 686 } 687 return (xstrdup(buf)); 688 #undef EXPAND_MAX_KEYS 689 } 690 691 /* 692 * Read an entire line from a public key file into a static buffer, discarding 693 * lines that exceed the buffer size. Returns 0 on success, -1 on failure. 694 */ 695 int 696 read_keyfile_line(FILE *f, const char *filename, char *buf, size_t bufsz, 697 u_long *lineno) 698 { 699 while (fgets(buf, bufsz, f) != NULL) { 700 if (buf[0] == '\0') 701 continue; 702 (*lineno)++; 703 if (buf[strlen(buf) - 1] == '\n' || feof(f)) { 704 return 0; 705 } else { 706 debug("%s: %s line %lu exceeds size limit", __func__, 707 filename, *lineno); 708 /* discard remainder of line */ 709 while (fgetc(f) != '\n' && !feof(f)) 710 ; /* nothing */ 711 } 712 } 713 return -1; 714 } 715 716 int 717 tun_open(int tun, int mode) 718 { 719 #if defined(CUSTOM_SYS_TUN_OPEN) 720 return (sys_tun_open(tun, mode)); 721 #elif defined(SSH_TUN_OPENBSD) 722 struct ifreq ifr; 723 char name[100]; 724 int fd = -1, sock; 725 const char *tunbase = "tun"; 726 727 if (mode == SSH_TUNMODE_ETHERNET) 728 tunbase = "tap"; 729 730 /* Open the tunnel device */ 731 if (tun <= SSH_TUNID_MAX) { 732 snprintf(name, sizeof(name), "/dev/%s%d", tunbase, tun); 733 fd = open(name, O_RDWR); 734 } else if (tun == SSH_TUNID_ANY) { 735 for (tun = 100; tun >= 0; tun--) { 736 snprintf(name, sizeof(name), "/dev/%s%d", 737 tunbase, tun); 738 if ((fd = open(name, O_RDWR)) >= 0) 739 break; 740 } 741 } else { 742 debug("%s: invalid tunnel %u", __func__, tun); 743 return -1; 744 } 745 746 if (fd < 0) { 747 debug("%s: %s open: %s", __func__, name, strerror(errno)); 748 return -1; 749 } 750 751 debug("%s: %s mode %d fd %d", __func__, name, mode, fd); 752 753 /* Bring interface up if it is not already */ 754 snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s%d", tunbase, tun); 755 if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1) 756 goto failed; 757 758 if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1) { 759 debug("%s: get interface %s flags: %s", __func__, 760 ifr.ifr_name, strerror(errno)); 761 goto failed; 762 } 763 764 if (!(ifr.ifr_flags & IFF_UP)) { 765 ifr.ifr_flags |= IFF_UP; 766 if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1) { 767 debug("%s: activate interface %s: %s", __func__, 768 ifr.ifr_name, strerror(errno)); 769 goto failed; 770 } 771 } 772 773 close(sock); 774 return fd; 775 776 failed: 777 if (fd >= 0) 778 close(fd); 779 if (sock >= 0) 780 close(sock); 781 return -1; 782 #else 783 error("Tunnel interfaces are not supported on this platform"); 784 return (-1); 785 #endif 786 } 787 788 void 789 sanitise_stdfd(void) 790 { 791 int nullfd, dupfd; 792 793 if ((nullfd = dupfd = open(_PATH_DEVNULL, O_RDWR)) == -1) { 794 fprintf(stderr, "Couldn't open /dev/null: %s\n", 795 strerror(errno)); 796 exit(1); 797 } 798 while (++dupfd <= STDERR_FILENO) { 799 /* Only populate closed fds. */ 800 if (fcntl(dupfd, F_GETFL) == -1 && errno == EBADF) { 801 if (dup2(nullfd, dupfd) == -1) { 802 fprintf(stderr, "dup2: %s\n", strerror(errno)); 803 exit(1); 804 } 805 } 806 } 807 if (nullfd > STDERR_FILENO) 808 close(nullfd); 809 } 810 811 char * 812 tohex(const void *vp, size_t l) 813 { 814 const u_char *p = (const u_char *)vp; 815 char b[3], *r; 816 size_t i, hl; 817 818 if (l > 65536) 819 return xstrdup("tohex: length > 65536"); 820 821 hl = l * 2 + 1; 822 r = xcalloc(1, hl); 823 for (i = 0; i < l; i++) { 824 snprintf(b, sizeof(b), "%02x", p[i]); 825 strlcat(r, b, hl); 826 } 827 return (r); 828 } 829 830 u_int64_t 831 get_u64(const void *vp) 832 { 833 const u_char *p = (const u_char *)vp; 834 u_int64_t v; 835 836 v = (u_int64_t)p[0] << 56; 837 v |= (u_int64_t)p[1] << 48; 838 v |= (u_int64_t)p[2] << 40; 839 v |= (u_int64_t)p[3] << 32; 840 v |= (u_int64_t)p[4] << 24; 841 v |= (u_int64_t)p[5] << 16; 842 v |= (u_int64_t)p[6] << 8; 843 v |= (u_int64_t)p[7]; 844 845 return (v); 846 } 847 848 u_int32_t 849 get_u32(const void *vp) 850 { 851 const u_char *p = (const u_char *)vp; 852 u_int32_t v; 853 854 v = (u_int32_t)p[0] << 24; 855 v |= (u_int32_t)p[1] << 16; 856 v |= (u_int32_t)p[2] << 8; 857 v |= (u_int32_t)p[3]; 858 859 return (v); 860 } 861 862 u_int32_t 863 get_u32_le(const void *vp) 864 { 865 const u_char *p = (const u_char *)vp; 866 u_int32_t v; 867 868 v = (u_int32_t)p[0]; 869 v |= (u_int32_t)p[1] << 8; 870 v |= (u_int32_t)p[2] << 16; 871 v |= (u_int32_t)p[3] << 24; 872 873 return (v); 874 } 875 876 u_int16_t 877 get_u16(const void *vp) 878 { 879 const u_char *p = (const u_char *)vp; 880 u_int16_t v; 881 882 v = (u_int16_t)p[0] << 8; 883 v |= (u_int16_t)p[1]; 884 885 return (v); 886 } 887 888 void 889 put_u64(void *vp, u_int64_t v) 890 { 891 u_char *p = (u_char *)vp; 892 893 p[0] = (u_char)(v >> 56) & 0xff; 894 p[1] = (u_char)(v >> 48) & 0xff; 895 p[2] = (u_char)(v >> 40) & 0xff; 896 p[3] = (u_char)(v >> 32) & 0xff; 897 p[4] = (u_char)(v >> 24) & 0xff; 898 p[5] = (u_char)(v >> 16) & 0xff; 899 p[6] = (u_char)(v >> 8) & 0xff; 900 p[7] = (u_char)v & 0xff; 901 } 902 903 void 904 put_u32(void *vp, u_int32_t v) 905 { 906 u_char *p = (u_char *)vp; 907 908 p[0] = (u_char)(v >> 24) & 0xff; 909 p[1] = (u_char)(v >> 16) & 0xff; 910 p[2] = (u_char)(v >> 8) & 0xff; 911 p[3] = (u_char)v & 0xff; 912 } 913 914 void 915 put_u32_le(void *vp, u_int32_t v) 916 { 917 u_char *p = (u_char *)vp; 918 919 p[0] = (u_char)v & 0xff; 920 p[1] = (u_char)(v >> 8) & 0xff; 921 p[2] = (u_char)(v >> 16) & 0xff; 922 p[3] = (u_char)(v >> 24) & 0xff; 923 } 924 925 void 926 put_u16(void *vp, u_int16_t v) 927 { 928 u_char *p = (u_char *)vp; 929 930 p[0] = (u_char)(v >> 8) & 0xff; 931 p[1] = (u_char)v & 0xff; 932 } 933 934 void 935 ms_subtract_diff(struct timeval *start, int *ms) 936 { 937 struct timeval diff, finish; 938 939 gettimeofday(&finish, NULL); 940 timersub(&finish, start, &diff); 941 *ms -= (diff.tv_sec * 1000) + (diff.tv_usec / 1000); 942 } 943 944 void 945 ms_to_timeval(struct timeval *tv, int ms) 946 { 947 if (ms < 0) 948 ms = 0; 949 tv->tv_sec = ms / 1000; 950 tv->tv_usec = (ms % 1000) * 1000; 951 } 952 953 time_t 954 monotime(void) 955 { 956 #if defined(HAVE_CLOCK_GETTIME) && \ 957 (defined(CLOCK_MONOTONIC) || defined(CLOCK_BOOTTIME)) 958 struct timespec ts; 959 static int gettime_failed = 0; 960 961 if (!gettime_failed) { 962 #if defined(CLOCK_BOOTTIME) 963 if (clock_gettime(CLOCK_BOOTTIME, &ts) == 0) 964 return (ts.tv_sec); 965 #endif 966 #if defined(CLOCK_MONOTONIC) 967 if (clock_gettime(CLOCK_MONOTONIC, &ts) == 0) 968 return (ts.tv_sec); 969 #endif 970 debug3("clock_gettime: %s", strerror(errno)); 971 gettime_failed = 1; 972 } 973 #endif /* HAVE_CLOCK_GETTIME && (CLOCK_MONOTONIC || CLOCK_BOOTTIME */ 974 975 return time(NULL); 976 } 977 978 double 979 monotime_double(void) 980 { 981 #if defined(HAVE_CLOCK_GETTIME) && \ 982 (defined(CLOCK_MONOTONIC) || defined(CLOCK_BOOTTIME)) 983 struct timespec ts; 984 static int gettime_failed = 0; 985 986 if (!gettime_failed) { 987 #if defined(CLOCK_BOOTTIME) 988 if (clock_gettime(CLOCK_BOOTTIME, &ts) == 0) 989 return (ts.tv_sec + (double)ts.tv_nsec / 1000000000); 990 #endif 991 #if defined(CLOCK_MONOTONIC) 992 if (clock_gettime(CLOCK_MONOTONIC, &ts) == 0) 993 return (ts.tv_sec + (double)ts.tv_nsec / 1000000000); 994 #endif 995 debug3("clock_gettime: %s", strerror(errno)); 996 gettime_failed = 1; 997 } 998 #endif /* HAVE_CLOCK_GETTIME && (CLOCK_MONOTONIC || CLOCK_BOOTTIME */ 999 1000 return (double)time(NULL); 1001 } 1002 1003 void 1004 bandwidth_limit_init(struct bwlimit *bw, u_int64_t kbps, size_t buflen) 1005 { 1006 bw->buflen = buflen; 1007 bw->rate = kbps; 1008 bw->thresh = bw->rate; 1009 bw->lamt = 0; 1010 timerclear(&bw->bwstart); 1011 timerclear(&bw->bwend); 1012 } 1013 1014 /* Callback from read/write loop to insert bandwidth-limiting delays */ 1015 void 1016 bandwidth_limit(struct bwlimit *bw, size_t read_len) 1017 { 1018 u_int64_t waitlen; 1019 struct timespec ts, rm; 1020 1021 if (!timerisset(&bw->bwstart)) { 1022 gettimeofday(&bw->bwstart, NULL); 1023 return; 1024 } 1025 1026 bw->lamt += read_len; 1027 if (bw->lamt < bw->thresh) 1028 return; 1029 1030 gettimeofday(&bw->bwend, NULL); 1031 timersub(&bw->bwend, &bw->bwstart, &bw->bwend); 1032 if (!timerisset(&bw->bwend)) 1033 return; 1034 1035 bw->lamt *= 8; 1036 waitlen = (double)1000000L * bw->lamt / bw->rate; 1037 1038 bw->bwstart.tv_sec = waitlen / 1000000L; 1039 bw->bwstart.tv_usec = waitlen % 1000000L; 1040 1041 if (timercmp(&bw->bwstart, &bw->bwend, >)) { 1042 timersub(&bw->bwstart, &bw->bwend, &bw->bwend); 1043 1044 /* Adjust the wait time */ 1045 if (bw->bwend.tv_sec) { 1046 bw->thresh /= 2; 1047 if (bw->thresh < bw->buflen / 4) 1048 bw->thresh = bw->buflen / 4; 1049 } else if (bw->bwend.tv_usec < 10000) { 1050 bw->thresh *= 2; 1051 if (bw->thresh > bw->buflen * 8) 1052 bw->thresh = bw->buflen * 8; 1053 } 1054 1055 TIMEVAL_TO_TIMESPEC(&bw->bwend, &ts); 1056 while (nanosleep(&ts, &rm) == -1) { 1057 if (errno != EINTR) 1058 break; 1059 ts = rm; 1060 } 1061 } 1062 1063 bw->lamt = 0; 1064 gettimeofday(&bw->bwstart, NULL); 1065 } 1066 1067 /* Make a template filename for mk[sd]temp() */ 1068 void 1069 mktemp_proto(char *s, size_t len) 1070 { 1071 const char *tmpdir; 1072 int r; 1073 1074 if ((tmpdir = getenv("TMPDIR")) != NULL) { 1075 r = snprintf(s, len, "%s/ssh-XXXXXXXXXXXX", tmpdir); 1076 if (r > 0 && (size_t)r < len) 1077 return; 1078 } 1079 r = snprintf(s, len, "/tmp/ssh-XXXXXXXXXXXX"); 1080 if (r < 0 || (size_t)r >= len) 1081 fatal("%s: template string too short", __func__); 1082 } 1083 1084 static const struct { 1085 const char *name; 1086 int value; 1087 } ipqos[] = { 1088 { "af11", IPTOS_DSCP_AF11 }, 1089 { "af12", IPTOS_DSCP_AF12 }, 1090 { "af13", IPTOS_DSCP_AF13 }, 1091 { "af21", IPTOS_DSCP_AF21 }, 1092 { "af22", IPTOS_DSCP_AF22 }, 1093 { "af23", IPTOS_DSCP_AF23 }, 1094 { "af31", IPTOS_DSCP_AF31 }, 1095 { "af32", IPTOS_DSCP_AF32 }, 1096 { "af33", IPTOS_DSCP_AF33 }, 1097 { "af41", IPTOS_DSCP_AF41 }, 1098 { "af42", IPTOS_DSCP_AF42 }, 1099 { "af43", IPTOS_DSCP_AF43 }, 1100 { "cs0", IPTOS_DSCP_CS0 }, 1101 { "cs1", IPTOS_DSCP_CS1 }, 1102 { "cs2", IPTOS_DSCP_CS2 }, 1103 { "cs3", IPTOS_DSCP_CS3 }, 1104 { "cs4", IPTOS_DSCP_CS4 }, 1105 { "cs5", IPTOS_DSCP_CS5 }, 1106 { "cs6", IPTOS_DSCP_CS6 }, 1107 { "cs7", IPTOS_DSCP_CS7 }, 1108 { "ef", IPTOS_DSCP_EF }, 1109 { "lowdelay", IPTOS_LOWDELAY }, 1110 { "throughput", IPTOS_THROUGHPUT }, 1111 { "reliability", IPTOS_RELIABILITY }, 1112 { NULL, -1 } 1113 }; 1114 1115 int 1116 parse_ipqos(const char *cp) 1117 { 1118 u_int i; 1119 char *ep; 1120 long val; 1121 1122 if (cp == NULL) 1123 return -1; 1124 for (i = 0; ipqos[i].name != NULL; i++) { 1125 if (strcasecmp(cp, ipqos[i].name) == 0) 1126 return ipqos[i].value; 1127 } 1128 /* Try parsing as an integer */ 1129 val = strtol(cp, &ep, 0); 1130 if (*cp == '\0' || *ep != '\0' || val < 0 || val > 255) 1131 return -1; 1132 return val; 1133 } 1134 1135 const char * 1136 iptos2str(int iptos) 1137 { 1138 int i; 1139 static char iptos_str[sizeof "0xff"]; 1140 1141 for (i = 0; ipqos[i].name != NULL; i++) { 1142 if (ipqos[i].value == iptos) 1143 return ipqos[i].name; 1144 } 1145 snprintf(iptos_str, sizeof iptos_str, "0x%02x", iptos); 1146 return iptos_str; 1147 } 1148 1149 void 1150 lowercase(char *s) 1151 { 1152 for (; *s; s++) 1153 *s = tolower((u_char)*s); 1154 } 1155 1156 int 1157 unix_listener(const char *path, int backlog, int unlink_first) 1158 { 1159 struct sockaddr_un sunaddr; 1160 int saved_errno, sock; 1161 1162 memset(&sunaddr, 0, sizeof(sunaddr)); 1163 sunaddr.sun_family = AF_UNIX; 1164 if (strlcpy(sunaddr.sun_path, path, sizeof(sunaddr.sun_path)) >= sizeof(sunaddr.sun_path)) { 1165 error("%s: \"%s\" too long for Unix domain socket", __func__, 1166 path); 1167 errno = ENAMETOOLONG; 1168 return -1; 1169 } 1170 1171 sock = socket(PF_UNIX, SOCK_STREAM, 0); 1172 if (sock < 0) { 1173 saved_errno = errno; 1174 error("socket: %.100s", strerror(errno)); 1175 errno = saved_errno; 1176 return -1; 1177 } 1178 if (unlink_first == 1) { 1179 if (unlink(path) != 0 && errno != ENOENT) 1180 error("unlink(%s): %.100s", path, strerror(errno)); 1181 } 1182 if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) < 0) { 1183 saved_errno = errno; 1184 error("bind: %.100s", strerror(errno)); 1185 close(sock); 1186 error("%s: cannot bind to path: %s", __func__, path); 1187 errno = saved_errno; 1188 return -1; 1189 } 1190 if (listen(sock, backlog) < 0) { 1191 saved_errno = errno; 1192 error("listen: %.100s", strerror(errno)); 1193 close(sock); 1194 unlink(path); 1195 error("%s: cannot listen on path: %s", __func__, path); 1196 errno = saved_errno; 1197 return -1; 1198 } 1199 return sock; 1200 } 1201 1202 void 1203 sock_set_v6only(int s) 1204 { 1205 #if defined(IPV6_V6ONLY) && !defined(__OpenBSD__) 1206 int on = 1; 1207 1208 debug3("%s: set socket %d IPV6_V6ONLY", __func__, s); 1209 if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) == -1) 1210 error("setsockopt IPV6_V6ONLY: %s", strerror(errno)); 1211 #endif 1212 } 1213 1214 /* 1215 * Compares two strings that maybe be NULL. Returns non-zero if strings 1216 * are both NULL or are identical, returns zero otherwise. 1217 */ 1218 static int 1219 strcmp_maybe_null(const char *a, const char *b) 1220 { 1221 if ((a == NULL && b != NULL) || (a != NULL && b == NULL)) 1222 return 0; 1223 if (a != NULL && strcmp(a, b) != 0) 1224 return 0; 1225 return 1; 1226 } 1227 1228 /* 1229 * Compare two forwards, returning non-zero if they are identical or 1230 * zero otherwise. 1231 */ 1232 int 1233 forward_equals(const struct Forward *a, const struct Forward *b) 1234 { 1235 if (strcmp_maybe_null(a->listen_host, b->listen_host) == 0) 1236 return 0; 1237 if (a->listen_port != b->listen_port) 1238 return 0; 1239 if (strcmp_maybe_null(a->listen_path, b->listen_path) == 0) 1240 return 0; 1241 if (strcmp_maybe_null(a->connect_host, b->connect_host) == 0) 1242 return 0; 1243 if (a->connect_port != b->connect_port) 1244 return 0; 1245 if (strcmp_maybe_null(a->connect_path, b->connect_path) == 0) 1246 return 0; 1247 /* allocated_port and handle are not checked */ 1248 return 1; 1249 } 1250 1251 /* returns 1 if bind to specified port by specified user is permitted */ 1252 int 1253 bind_permitted(int port, uid_t uid) 1254 { 1255 if (port < IPPORT_RESERVED && uid != 0) 1256 return 0; 1257 return 1; 1258 } 1259 1260 /* returns 1 if process is already daemonized, 0 otherwise */ 1261 int 1262 daemonized(void) 1263 { 1264 int fd; 1265 1266 if ((fd = open(_PATH_TTY, O_RDONLY | O_NOCTTY)) >= 0) { 1267 close(fd); 1268 return 0; /* have controlling terminal */ 1269 } 1270 if (getppid() != 1) 1271 return 0; /* parent is not init */ 1272 if (getsid(0) != getpid()) 1273 return 0; /* not session leader */ 1274 debug3("already daemonized"); 1275 return 1; 1276 } 1277
