1 /* $OpenBSD: misc.c,v 1.137 2019/01/23 21:50:56 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/stat.h> 33 #include <sys/time.h> 34 #include <sys/wait.h> 35 #include <sys/un.h> 36 37 #include <limits.h> 38 #ifdef HAVE_LIBGEN_H 39 # include <libgen.h> 40 #endif 41 #include <poll.h> 42 #include <signal.h> 43 #include <stdarg.h> 44 #include <stdio.h> 45 #include <stdlib.h> 46 #include <string.h> 47 #include <time.h> 48 #include <unistd.h> 49 50 #include <netinet/in.h> 51 #include <netinet/in_systm.h> 52 #include <netinet/ip.h> 53 #include <netinet/tcp.h> 54 #include <arpa/inet.h> 55 56 #include <ctype.h> 57 #include <errno.h> 58 #include <fcntl.h> 59 #include <netdb.h> 60 #ifdef HAVE_PATHS_H 61 # include <paths.h> 62 #include <pwd.h> 63 #endif 64 #ifdef SSH_TUN_OPENBSD 65 #include <net/if.h> 66 #endif 67 68 #include "xmalloc.h" 69 #include "misc.h" 70 #include "log.h" 71 #include "ssh.h" 72 #include "sshbuf.h" 73 #include "ssherr.h" 74 #include "platform.h" 75 76 /* remove newline at end of string */ 77 char * 78 chop(char *s) 79 { 80 char *t = s; 81 while (*t) { 82 if (*t == '\n' || *t == '\r') { 83 *t = '\0'; 84 return s; 85 } 86 t++; 87 } 88 return s; 89 90 } 91 92 /* set/unset filedescriptor to non-blocking */ 93 int 94 set_nonblock(int fd) 95 { 96 int val; 97 98 val = fcntl(fd, F_GETFL); 99 if (val < 0) { 100 error("fcntl(%d, F_GETFL): %s", fd, strerror(errno)); 101 return (-1); 102 } 103 if (val & O_NONBLOCK) { 104 debug3("fd %d is O_NONBLOCK", fd); 105 return (0); 106 } 107 debug2("fd %d setting O_NONBLOCK", fd); 108 val |= O_NONBLOCK; 109 if (fcntl(fd, F_SETFL, val) == -1) { 110 debug("fcntl(%d, F_SETFL, O_NONBLOCK): %s", fd, 111 strerror(errno)); 112 return (-1); 113 } 114 return (0); 115 } 116 117 int 118 unset_nonblock(int fd) 119 { 120 int val; 121 122 val = fcntl(fd, F_GETFL); 123 if (val < 0) { 124 error("fcntl(%d, F_GETFL): %s", fd, strerror(errno)); 125 return (-1); 126 } 127 if (!(val & O_NONBLOCK)) { 128 debug3("fd %d is not O_NONBLOCK", fd); 129 return (0); 130 } 131 debug("fd %d clearing O_NONBLOCK", fd); 132 val &= ~O_NONBLOCK; 133 if (fcntl(fd, F_SETFL, val) == -1) { 134 debug("fcntl(%d, F_SETFL, ~O_NONBLOCK): %s", 135 fd, strerror(errno)); 136 return (-1); 137 } 138 return (0); 139 } 140 141 const char * 142 ssh_gai_strerror(int gaierr) 143 { 144 if (gaierr == EAI_SYSTEM && errno != 0) 145 return strerror(errno); 146 return gai_strerror(gaierr); 147 } 148 149 /* disable nagle on socket */ 150 void 151 set_nodelay(int fd) 152 { 153 int opt; 154 socklen_t optlen; 155 156 optlen = sizeof opt; 157 if (getsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, &optlen) == -1) { 158 debug("getsockopt TCP_NODELAY: %.100s", strerror(errno)); 159 return; 160 } 161 if (opt == 1) { 162 debug2("fd %d is TCP_NODELAY", fd); 163 return; 164 } 165 opt = 1; 166 debug2("fd %d setting TCP_NODELAY", fd); 167 if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &opt, sizeof opt) == -1) 168 error("setsockopt TCP_NODELAY: %.100s", strerror(errno)); 169 } 170 171 /* Allow local port reuse in TIME_WAIT */ 172 int 173 set_reuseaddr(int fd) 174 { 175 int on = 1; 176 177 if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)) == -1) { 178 error("setsockopt SO_REUSEADDR fd %d: %s", fd, strerror(errno)); 179 return -1; 180 } 181 return 0; 182 } 183 184 /* Get/set routing domain */ 185 char * 186 get_rdomain(int fd) 187 { 188 #if defined(HAVE_SYS_GET_RDOMAIN) 189 return sys_get_rdomain(fd); 190 #elif defined(__OpenBSD__) 191 int rtable; 192 char *ret; 193 socklen_t len = sizeof(rtable); 194 195 if (getsockopt(fd, SOL_SOCKET, SO_RTABLE, &rtable, &len) == -1) { 196 error("Failed to get routing domain for fd %d: %s", 197 fd, strerror(errno)); 198 return NULL; 199 } 200 xasprintf(&ret, "%d", rtable); 201 return ret; 202 #else /* defined(__OpenBSD__) */ 203 return NULL; 204 #endif 205 } 206 207 int 208 set_rdomain(int fd, const char *name) 209 { 210 #if defined(HAVE_SYS_SET_RDOMAIN) 211 return sys_set_rdomain(fd, name); 212 #elif defined(__OpenBSD__) 213 int rtable; 214 const char *errstr; 215 216 if (name == NULL) 217 return 0; /* default table */ 218 219 rtable = (int)strtonum(name, 0, 255, &errstr); 220 if (errstr != NULL) { 221 /* Shouldn't happen */ 222 error("Invalid routing domain \"%s\": %s", name, errstr); 223 return -1; 224 } 225 if (setsockopt(fd, SOL_SOCKET, SO_RTABLE, 226 &rtable, sizeof(rtable)) == -1) { 227 error("Failed to set routing domain %d on fd %d: %s", 228 rtable, fd, strerror(errno)); 229 return -1; 230 } 231 return 0; 232 #else /* defined(__OpenBSD__) */ 233 error("Setting routing domain is not supported on this platform"); 234 return -1; 235 #endif 236 } 237 238 /* 239 * Wait up to *timeoutp milliseconds for fd to be readable. Updates 240 * *timeoutp with time remaining. 241 * Returns 0 if fd ready or -1 on timeout or error (see errno). 242 */ 243 int 244 waitrfd(int fd, int *timeoutp) 245 { 246 struct pollfd pfd; 247 struct timeval t_start; 248 int oerrno, r; 249 250 monotime_tv(&t_start); 251 pfd.fd = fd; 252 pfd.events = POLLIN; 253 for (; *timeoutp >= 0;) { 254 r = poll(&pfd, 1, *timeoutp); 255 oerrno = errno; 256 ms_subtract_diff(&t_start, timeoutp); 257 errno = oerrno; 258 if (r > 0) 259 return 0; 260 else if (r == -1 && errno != EAGAIN) 261 return -1; 262 else if (r == 0) 263 break; 264 } 265 /* timeout */ 266 errno = ETIMEDOUT; 267 return -1; 268 } 269 270 /* 271 * Attempt a non-blocking connect(2) to the specified address, waiting up to 272 * *timeoutp milliseconds for the connection to complete. If the timeout is 273 * <=0, then wait indefinitely. 274 * 275 * Returns 0 on success or -1 on failure. 276 */ 277 int 278 timeout_connect(int sockfd, const struct sockaddr *serv_addr, 279 socklen_t addrlen, int *timeoutp) 280 { 281 int optval = 0; 282 socklen_t optlen = sizeof(optval); 283 284 /* No timeout: just do a blocking connect() */ 285 if (timeoutp == NULL || *timeoutp <= 0) 286 return connect(sockfd, serv_addr, addrlen); 287 288 set_nonblock(sockfd); 289 if (connect(sockfd, serv_addr, addrlen) == 0) { 290 /* Succeeded already? */ 291 unset_nonblock(sockfd); 292 return 0; 293 } else if (errno != EINPROGRESS) 294 return -1; 295 296 if (waitrfd(sockfd, timeoutp) == -1) 297 return -1; 298 299 /* Completed or failed */ 300 if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &optval, &optlen) == -1) { 301 debug("getsockopt: %s", strerror(errno)); 302 return -1; 303 } 304 if (optval != 0) { 305 errno = optval; 306 return -1; 307 } 308 unset_nonblock(sockfd); 309 return 0; 310 } 311 312 /* Characters considered whitespace in strsep calls. */ 313 #define WHITESPACE " \t\r\n" 314 #define QUOTE "\"" 315 316 /* return next token in configuration line */ 317 static char * 318 strdelim_internal(char **s, int split_equals) 319 { 320 char *old; 321 int wspace = 0; 322 323 if (*s == NULL) 324 return NULL; 325 326 old = *s; 327 328 *s = strpbrk(*s, 329 split_equals ? WHITESPACE QUOTE "=" : WHITESPACE QUOTE); 330 if (*s == NULL) 331 return (old); 332 333 if (*s[0] == '\"') { 334 memmove(*s, *s + 1, strlen(*s)); /* move nul too */ 335 /* Find matching quote */ 336 if ((*s = strpbrk(*s, QUOTE)) == NULL) { 337 return (NULL); /* no matching quote */ 338 } else { 339 *s[0] = '\0'; 340 *s += strspn(*s + 1, WHITESPACE) + 1; 341 return (old); 342 } 343 } 344 345 /* Allow only one '=' to be skipped */ 346 if (split_equals && *s[0] == '=') 347 wspace = 1; 348 *s[0] = '\0'; 349 350 /* Skip any extra whitespace after first token */ 351 *s += strspn(*s + 1, WHITESPACE) + 1; 352 if (split_equals && *s[0] == '=' && !wspace) 353 *s += strspn(*s + 1, WHITESPACE) + 1; 354 355 return (old); 356 } 357 358 /* 359 * Return next token in configuration line; splts on whitespace or a 360 * single '=' character. 361 */ 362 char * 363 strdelim(char **s) 364 { 365 return strdelim_internal(s, 1); 366 } 367 368 /* 369 * Return next token in configuration line; splts on whitespace only. 370 */ 371 char * 372 strdelimw(char **s) 373 { 374 return strdelim_internal(s, 0); 375 } 376 377 struct passwd * 378 pwcopy(struct passwd *pw) 379 { 380 struct passwd *copy = xcalloc(1, sizeof(*copy)); 381 382 copy->pw_name = xstrdup(pw->pw_name); 383 copy->pw_passwd = xstrdup(pw->pw_passwd); 384 #ifdef HAVE_STRUCT_PASSWD_PW_GECOS 385 copy->pw_gecos = xstrdup(pw->pw_gecos); 386 #endif 387 copy->pw_uid = pw->pw_uid; 388 copy->pw_gid = pw->pw_gid; 389 #ifdef HAVE_STRUCT_PASSWD_PW_EXPIRE 390 copy->pw_expire = pw->pw_expire; 391 #endif 392 #ifdef HAVE_STRUCT_PASSWD_PW_CHANGE 393 copy->pw_change = pw->pw_change; 394 #endif 395 #ifdef HAVE_STRUCT_PASSWD_PW_CLASS 396 copy->pw_class = xstrdup(pw->pw_class); 397 #endif 398 copy->pw_dir = xstrdup(pw->pw_dir); 399 copy->pw_shell = xstrdup(pw->pw_shell); 400 return copy; 401 } 402 403 /* 404 * Convert ASCII string to TCP/IP port number. 405 * Port must be >=0 and <=65535. 406 * Return -1 if invalid. 407 */ 408 int 409 a2port(const char *s) 410 { 411 struct servent *se; 412 long long port; 413 const char *errstr; 414 415 port = strtonum(s, 0, 65535, &errstr); 416 if (errstr == NULL) 417 return (int)port; 418 if ((se = getservbyname(s, "tcp")) != NULL) 419 return ntohs(se->s_port); 420 return -1; 421 } 422 423 int 424 a2tun(const char *s, int *remote) 425 { 426 const char *errstr = NULL; 427 char *sp, *ep; 428 int tun; 429 430 if (remote != NULL) { 431 *remote = SSH_TUNID_ANY; 432 sp = xstrdup(s); 433 if ((ep = strchr(sp, ':')) == NULL) { 434 free(sp); 435 return (a2tun(s, NULL)); 436 } 437 ep[0] = '\0'; ep++; 438 *remote = a2tun(ep, NULL); 439 tun = a2tun(sp, NULL); 440 free(sp); 441 return (*remote == SSH_TUNID_ERR ? *remote : tun); 442 } 443 444 if (strcasecmp(s, "any") == 0) 445 return (SSH_TUNID_ANY); 446 447 tun = strtonum(s, 0, SSH_TUNID_MAX, &errstr); 448 if (errstr != NULL) 449 return (SSH_TUNID_ERR); 450 451 return (tun); 452 } 453 454 #define SECONDS 1 455 #define MINUTES (SECONDS * 60) 456 #define HOURS (MINUTES * 60) 457 #define DAYS (HOURS * 24) 458 #define WEEKS (DAYS * 7) 459 460 /* 461 * Convert a time string into seconds; format is 462 * a sequence of: 463 * time[qualifier] 464 * 465 * Valid time qualifiers are: 466 * <none> seconds 467 * s|S seconds 468 * m|M minutes 469 * h|H hours 470 * d|D days 471 * w|W weeks 472 * 473 * Examples: 474 * 90m 90 minutes 475 * 1h30m 90 minutes 476 * 2d 2 days 477 * 1w 1 week 478 * 479 * Return -1 if time string is invalid. 480 */ 481 long 482 convtime(const char *s) 483 { 484 long total, secs, multiplier = 1; 485 const char *p; 486 char *endp; 487 488 errno = 0; 489 total = 0; 490 p = s; 491 492 if (p == NULL || *p == '\0') 493 return -1; 494 495 while (*p) { 496 secs = strtol(p, &endp, 10); 497 if (p == endp || 498 (errno == ERANGE && (secs == LONG_MIN || secs == LONG_MAX)) || 499 secs < 0) 500 return -1; 501 502 switch (*endp++) { 503 case '\0': 504 endp--; 505 break; 506 case 's': 507 case 'S': 508 break; 509 case 'm': 510 case 'M': 511 multiplier = MINUTES; 512 break; 513 case 'h': 514 case 'H': 515 multiplier = HOURS; 516 break; 517 case 'd': 518 case 'D': 519 multiplier = DAYS; 520 break; 521 case 'w': 522 case 'W': 523 multiplier = WEEKS; 524 break; 525 default: 526 return -1; 527 } 528 if (secs >= LONG_MAX / multiplier) 529 return -1; 530 secs *= multiplier; 531 if (total >= LONG_MAX - secs) 532 return -1; 533 total += secs; 534 if (total < 0) 535 return -1; 536 p = endp; 537 } 538 539 return total; 540 } 541 542 /* 543 * Returns a standardized host+port identifier string. 544 * Caller must free returned string. 545 */ 546 char * 547 put_host_port(const char *host, u_short port) 548 { 549 char *hoststr; 550 551 if (port == 0 || port == SSH_DEFAULT_PORT) 552 return(xstrdup(host)); 553 if (asprintf(&hoststr, "[%s]:%d", host, (int)port) < 0) 554 fatal("put_host_port: asprintf: %s", strerror(errno)); 555 debug3("put_host_port: %s", hoststr); 556 return hoststr; 557 } 558 559 /* 560 * Search for next delimiter between hostnames/addresses and ports. 561 * Argument may be modified (for termination). 562 * Returns *cp if parsing succeeds. 563 * *cp is set to the start of the next field, if one was found. 564 * The delimiter char, if present, is stored in delim. 565 * If this is the last field, *cp is set to NULL. 566 */ 567 char * 568 hpdelim2(char **cp, char *delim) 569 { 570 char *s, *old; 571 572 if (cp == NULL || *cp == NULL) 573 return NULL; 574 575 old = s = *cp; 576 if (*s == '[') { 577 if ((s = strchr(s, ']')) == NULL) 578 return NULL; 579 else 580 s++; 581 } else if ((s = strpbrk(s, ":/")) == NULL) 582 s = *cp + strlen(*cp); /* skip to end (see first case below) */ 583 584 switch (*s) { 585 case '\0': 586 *cp = NULL; /* no more fields*/ 587 break; 588 589 case ':': 590 case '/': 591 if (delim != NULL) 592 *delim = *s; 593 *s = '\0'; /* terminate */ 594 *cp = s + 1; 595 break; 596 597 default: 598 return NULL; 599 } 600 601 return old; 602 } 603 604 char * 605 hpdelim(char **cp) 606 { 607 return hpdelim2(cp, NULL); 608 } 609 610 char * 611 cleanhostname(char *host) 612 { 613 if (*host == '[' && host[strlen(host) - 1] == ']') { 614 host[strlen(host) - 1] = '\0'; 615 return (host + 1); 616 } else 617 return host; 618 } 619 620 char * 621 colon(char *cp) 622 { 623 int flag = 0; 624 625 if (*cp == ':') /* Leading colon is part of file name. */ 626 return NULL; 627 if (*cp == '[') 628 flag = 1; 629 630 for (; *cp; ++cp) { 631 if (*cp == '@' && *(cp+1) == '[') 632 flag = 1; 633 if (*cp == ']' && *(cp+1) == ':' && flag) 634 return (cp+1); 635 if (*cp == ':' && !flag) 636 return (cp); 637 if (*cp == '/') 638 return NULL; 639 } 640 return NULL; 641 } 642 643 /* 644 * Parse a [user@]host:[path] string. 645 * Caller must free returned user, host and path. 646 * Any of the pointer return arguments may be NULL (useful for syntax checking). 647 * If user was not specified then *userp will be set to NULL. 648 * If host was not specified then *hostp will be set to NULL. 649 * If path was not specified then *pathp will be set to ".". 650 * Returns 0 on success, -1 on failure. 651 */ 652 int 653 parse_user_host_path(const char *s, char **userp, char **hostp, char **pathp) 654 { 655 char *user = NULL, *host = NULL, *path = NULL; 656 char *sdup, *tmp; 657 int ret = -1; 658 659 if (userp != NULL) 660 *userp = NULL; 661 if (hostp != NULL) 662 *hostp = NULL; 663 if (pathp != NULL) 664 *pathp = NULL; 665 666 sdup = xstrdup(s); 667 668 /* Check for remote syntax: [user@]host:[path] */ 669 if ((tmp = colon(sdup)) == NULL) 670 goto out; 671 672 /* Extract optional path */ 673 *tmp++ = '\0'; 674 if (*tmp == '\0') 675 tmp = "."; 676 path = xstrdup(tmp); 677 678 /* Extract optional user and mandatory host */ 679 tmp = strrchr(sdup, '@'); 680 if (tmp != NULL) { 681 *tmp++ = '\0'; 682 host = xstrdup(cleanhostname(tmp)); 683 if (*sdup != '\0') 684 user = xstrdup(sdup); 685 } else { 686 host = xstrdup(cleanhostname(sdup)); 687 user = NULL; 688 } 689 690 /* Success */ 691 if (userp != NULL) { 692 *userp = user; 693 user = NULL; 694 } 695 if (hostp != NULL) { 696 *hostp = host; 697 host = NULL; 698 } 699 if (pathp != NULL) { 700 *pathp = path; 701 path = NULL; 702 } 703 ret = 0; 704 out: 705 free(sdup); 706 free(user); 707 free(host); 708 free(path); 709 return ret; 710 } 711 712 /* 713 * Parse a [user@]host[:port] string. 714 * Caller must free returned user and host. 715 * Any of the pointer return arguments may be NULL (useful for syntax checking). 716 * If user was not specified then *userp will be set to NULL. 717 * If port was not specified then *portp will be -1. 718 * Returns 0 on success, -1 on failure. 719 */ 720 int 721 parse_user_host_port(const char *s, char **userp, char **hostp, int *portp) 722 { 723 char *sdup, *cp, *tmp; 724 char *user = NULL, *host = NULL; 725 int port = -1, ret = -1; 726 727 if (userp != NULL) 728 *userp = NULL; 729 if (hostp != NULL) 730 *hostp = NULL; 731 if (portp != NULL) 732 *portp = -1; 733 734 if ((sdup = tmp = strdup(s)) == NULL) 735 return -1; 736 /* Extract optional username */ 737 if ((cp = strrchr(tmp, '@')) != NULL) { 738 *cp = '\0'; 739 if (*tmp == '\0') 740 goto out; 741 if ((user = strdup(tmp)) == NULL) 742 goto out; 743 tmp = cp + 1; 744 } 745 /* Extract mandatory hostname */ 746 if ((cp = hpdelim(&tmp)) == NULL || *cp == '\0') 747 goto out; 748 host = xstrdup(cleanhostname(cp)); 749 /* Convert and verify optional port */ 750 if (tmp != NULL && *tmp != '\0') { 751 if ((port = a2port(tmp)) <= 0) 752 goto out; 753 } 754 /* Success */ 755 if (userp != NULL) { 756 *userp = user; 757 user = NULL; 758 } 759 if (hostp != NULL) { 760 *hostp = host; 761 host = NULL; 762 } 763 if (portp != NULL) 764 *portp = port; 765 ret = 0; 766 out: 767 free(sdup); 768 free(user); 769 free(host); 770 return ret; 771 } 772 773 /* 774 * Converts a two-byte hex string to decimal. 775 * Returns the decimal value or -1 for invalid input. 776 */ 777 static int 778 hexchar(const char *s) 779 { 780 unsigned char result[2]; 781 int i; 782 783 for (i = 0; i < 2; i++) { 784 if (s[i] >= '0' && s[i] <= '9') 785 result[i] = (unsigned char)(s[i] - '0'); 786 else if (s[i] >= 'a' && s[i] <= 'f') 787 result[i] = (unsigned char)(s[i] - 'a') + 10; 788 else if (s[i] >= 'A' && s[i] <= 'F') 789 result[i] = (unsigned char)(s[i] - 'A') + 10; 790 else 791 return -1; 792 } 793 return (result[0] << 4) | result[1]; 794 } 795 796 /* 797 * Decode an url-encoded string. 798 * Returns a newly allocated string on success or NULL on failure. 799 */ 800 static char * 801 urldecode(const char *src) 802 { 803 char *ret, *dst; 804 int ch; 805 806 ret = xmalloc(strlen(src) + 1); 807 for (dst = ret; *src != '\0'; src++) { 808 switch (*src) { 809 case '+': 810 *dst++ = ' '; 811 break; 812 case '%': 813 if (!isxdigit((unsigned char)src[1]) || 814 !isxdigit((unsigned char)src[2]) || 815 (ch = hexchar(src + 1)) == -1) { 816 free(ret); 817 return NULL; 818 } 819 *dst++ = ch; 820 src += 2; 821 break; 822 default: 823 *dst++ = *src; 824 break; 825 } 826 } 827 *dst = '\0'; 828 829 return ret; 830 } 831 832 /* 833 * Parse an (scp|ssh|sftp)://[user@]host[:port][/path] URI. 834 * See https://tools.ietf.org/html/draft-ietf-secsh-scp-sftp-ssh-uri-04 835 * Either user or path may be url-encoded (but not host or port). 836 * Caller must free returned user, host and path. 837 * Any of the pointer return arguments may be NULL (useful for syntax checking) 838 * but the scheme must always be specified. 839 * If user was not specified then *userp will be set to NULL. 840 * If port was not specified then *portp will be -1. 841 * If path was not specified then *pathp will be set to NULL. 842 * Returns 0 on success, 1 if non-uri/wrong scheme, -1 on error/invalid uri. 843 */ 844 int 845 parse_uri(const char *scheme, const char *uri, char **userp, char **hostp, 846 int *portp, char **pathp) 847 { 848 char *uridup, *cp, *tmp, ch; 849 char *user = NULL, *host = NULL, *path = NULL; 850 int port = -1, ret = -1; 851 size_t len; 852 853 len = strlen(scheme); 854 if (strncmp(uri, scheme, len) != 0 || strncmp(uri + len, "://", 3) != 0) 855 return 1; 856 uri += len + 3; 857 858 if (userp != NULL) 859 *userp = NULL; 860 if (hostp != NULL) 861 *hostp = NULL; 862 if (portp != NULL) 863 *portp = -1; 864 if (pathp != NULL) 865 *pathp = NULL; 866 867 uridup = tmp = xstrdup(uri); 868 869 /* Extract optional ssh-info (username + connection params) */ 870 if ((cp = strchr(tmp, '@')) != NULL) { 871 char *delim; 872 873 *cp = '\0'; 874 /* Extract username and connection params */ 875 if ((delim = strchr(tmp, ';')) != NULL) { 876 /* Just ignore connection params for now */ 877 *delim = '\0'; 878 } 879 if (*tmp == '\0') { 880 /* Empty username */ 881 goto out; 882 } 883 if ((user = urldecode(tmp)) == NULL) 884 goto out; 885 tmp = cp + 1; 886 } 887 888 /* Extract mandatory hostname */ 889 if ((cp = hpdelim2(&tmp, &ch)) == NULL || *cp == '\0') 890 goto out; 891 host = xstrdup(cleanhostname(cp)); 892 if (!valid_domain(host, 0, NULL)) 893 goto out; 894 895 if (tmp != NULL && *tmp != '\0') { 896 if (ch == ':') { 897 /* Convert and verify port. */ 898 if ((cp = strchr(tmp, '/')) != NULL) 899 *cp = '\0'; 900 if ((port = a2port(tmp)) <= 0) 901 goto out; 902 tmp = cp ? cp + 1 : NULL; 903 } 904 if (tmp != NULL && *tmp != '\0') { 905 /* Extract optional path */ 906 if ((path = urldecode(tmp)) == NULL) 907 goto out; 908 } 909 } 910 911 /* Success */ 912 if (userp != NULL) { 913 *userp = user; 914 user = NULL; 915 } 916 if (hostp != NULL) { 917 *hostp = host; 918 host = NULL; 919 } 920 if (portp != NULL) 921 *portp = port; 922 if (pathp != NULL) { 923 *pathp = path; 924 path = NULL; 925 } 926 ret = 0; 927 out: 928 free(uridup); 929 free(user); 930 free(host); 931 free(path); 932 return ret; 933 } 934 935 /* function to assist building execv() arguments */ 936 void 937 addargs(arglist *args, char *fmt, ...) 938 { 939 va_list ap; 940 char *cp; 941 u_int nalloc; 942 int r; 943 944 va_start(ap, fmt); 945 r = vasprintf(&cp, fmt, ap); 946 va_end(ap); 947 if (r == -1) 948 fatal("addargs: argument too long"); 949 950 nalloc = args->nalloc; 951 if (args->list == NULL) { 952 nalloc = 32; 953 args->num = 0; 954 } else if (args->num+2 >= nalloc) 955 nalloc *= 2; 956 957 args->list = xrecallocarray(args->list, args->nalloc, nalloc, sizeof(char *)); 958 args->nalloc = nalloc; 959 args->list[args->num++] = cp; 960 args->list[args->num] = NULL; 961 } 962 963 void 964 replacearg(arglist *args, u_int which, char *fmt, ...) 965 { 966 va_list ap; 967 char *cp; 968 int r; 969 970 va_start(ap, fmt); 971 r = vasprintf(&cp, fmt, ap); 972 va_end(ap); 973 if (r == -1) 974 fatal("replacearg: argument too long"); 975 976 if (which >= args->num) 977 fatal("replacearg: tried to replace invalid arg %d >= %d", 978 which, args->num); 979 free(args->list[which]); 980 args->list[which] = cp; 981 } 982 983 void 984 freeargs(arglist *args) 985 { 986 u_int i; 987 988 if (args->list != NULL) { 989 for (i = 0; i < args->num; i++) 990 free(args->list[i]); 991 free(args->list); 992 args->nalloc = args->num = 0; 993 args->list = NULL; 994 } 995 } 996 997 /* 998 * Expands tildes in the file name. Returns data allocated by xmalloc. 999 * Warning: this calls getpw*. 1000 */ 1001 char * 1002 tilde_expand_filename(const char *filename, uid_t uid) 1003 { 1004 const char *path, *sep; 1005 char user[128], *ret; 1006 struct passwd *pw; 1007 u_int len, slash; 1008 1009 if (*filename != '~') 1010 return (xstrdup(filename)); 1011 filename++; 1012 1013 path = strchr(filename, '/'); 1014 if (path != NULL && path > filename) { /* ~user/path */ 1015 slash = path - filename; 1016 if (slash > sizeof(user) - 1) 1017 fatal("tilde_expand_filename: ~username too long"); 1018 memcpy(user, filename, slash); 1019 user[slash] = '\0'; 1020 if ((pw = getpwnam(user)) == NULL) 1021 fatal("tilde_expand_filename: No such user %s", user); 1022 } else if ((pw = getpwuid(uid)) == NULL) /* ~/path */ 1023 fatal("tilde_expand_filename: No such uid %ld", (long)uid); 1024 1025 /* Make sure directory has a trailing '/' */ 1026 len = strlen(pw->pw_dir); 1027 if (len == 0 || pw->pw_dir[len - 1] != '/') 1028 sep = "/"; 1029 else 1030 sep = ""; 1031 1032 /* Skip leading '/' from specified path */ 1033 if (path != NULL) 1034 filename = path + 1; 1035 1036 if (xasprintf(&ret, "%s%s%s", pw->pw_dir, sep, filename) >= PATH_MAX) 1037 fatal("tilde_expand_filename: Path too long"); 1038 1039 return (ret); 1040 } 1041 1042 /* 1043 * Expand a string with a set of %[char] escapes. A number of escapes may be 1044 * specified as (char *escape_chars, char *replacement) pairs. The list must 1045 * be terminated by a NULL escape_char. Returns replaced string in memory 1046 * allocated by xmalloc. 1047 */ 1048 char * 1049 percent_expand(const char *string, ...) 1050 { 1051 #define EXPAND_MAX_KEYS 16 1052 u_int num_keys, i, j; 1053 struct { 1054 const char *key; 1055 const char *repl; 1056 } keys[EXPAND_MAX_KEYS]; 1057 char buf[4096]; 1058 va_list ap; 1059 1060 /* Gather keys */ 1061 va_start(ap, string); 1062 for (num_keys = 0; num_keys < EXPAND_MAX_KEYS; num_keys++) { 1063 keys[num_keys].key = va_arg(ap, char *); 1064 if (keys[num_keys].key == NULL) 1065 break; 1066 keys[num_keys].repl = va_arg(ap, char *); 1067 if (keys[num_keys].repl == NULL) 1068 fatal("%s: NULL replacement", __func__); 1069 } 1070 if (num_keys == EXPAND_MAX_KEYS && va_arg(ap, char *) != NULL) 1071 fatal("%s: too many keys", __func__); 1072 va_end(ap); 1073 1074 /* Expand string */ 1075 *buf = '\0'; 1076 for (i = 0; *string != '\0'; string++) { 1077 if (*string != '%') { 1078 append: 1079 buf[i++] = *string; 1080 if (i >= sizeof(buf)) 1081 fatal("%s: string too long", __func__); 1082 buf[i] = '\0'; 1083 continue; 1084 } 1085 string++; 1086 /* %% case */ 1087 if (*string == '%') 1088 goto append; 1089 if (*string == '\0') 1090 fatal("%s: invalid format", __func__); 1091 for (j = 0; j < num_keys; j++) { 1092 if (strchr(keys[j].key, *string) != NULL) { 1093 i = strlcat(buf, keys[j].repl, sizeof(buf)); 1094 if (i >= sizeof(buf)) 1095 fatal("%s: string too long", __func__); 1096 break; 1097 } 1098 } 1099 if (j >= num_keys) 1100 fatal("%s: unknown key %%%c", __func__, *string); 1101 } 1102 return (xstrdup(buf)); 1103 #undef EXPAND_MAX_KEYS 1104 } 1105 1106 int 1107 tun_open(int tun, int mode, char **ifname) 1108 { 1109 #if defined(CUSTOM_SYS_TUN_OPEN) 1110 return (sys_tun_open(tun, mode, ifname)); 1111 #elif defined(SSH_TUN_OPENBSD) 1112 struct ifreq ifr; 1113 char name[100]; 1114 int fd = -1, sock; 1115 const char *tunbase = "tun"; 1116 1117 if (ifname != NULL) 1118 *ifname = NULL; 1119 1120 if (mode == SSH_TUNMODE_ETHERNET) 1121 tunbase = "tap"; 1122 1123 /* Open the tunnel device */ 1124 if (tun <= SSH_TUNID_MAX) { 1125 snprintf(name, sizeof(name), "/dev/%s%d", tunbase, tun); 1126 fd = open(name, O_RDWR); 1127 } else if (tun == SSH_TUNID_ANY) { 1128 for (tun = 100; tun >= 0; tun--) { 1129 snprintf(name, sizeof(name), "/dev/%s%d", 1130 tunbase, tun); 1131 if ((fd = open(name, O_RDWR)) >= 0) 1132 break; 1133 } 1134 } else { 1135 debug("%s: invalid tunnel %u", __func__, tun); 1136 return -1; 1137 } 1138 1139 if (fd < 0) { 1140 debug("%s: %s open: %s", __func__, name, strerror(errno)); 1141 return -1; 1142 } 1143 1144 debug("%s: %s mode %d fd %d", __func__, name, mode, fd); 1145 1146 /* Bring interface up if it is not already */ 1147 snprintf(ifr.ifr_name, sizeof(ifr.ifr_name), "%s%d", tunbase, tun); 1148 if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) == -1) 1149 goto failed; 1150 1151 if (ioctl(sock, SIOCGIFFLAGS, &ifr) == -1) { 1152 debug("%s: get interface %s flags: %s", __func__, 1153 ifr.ifr_name, strerror(errno)); 1154 goto failed; 1155 } 1156 1157 if (!(ifr.ifr_flags & IFF_UP)) { 1158 ifr.ifr_flags |= IFF_UP; 1159 if (ioctl(sock, SIOCSIFFLAGS, &ifr) == -1) { 1160 debug("%s: activate interface %s: %s", __func__, 1161 ifr.ifr_name, strerror(errno)); 1162 goto failed; 1163 } 1164 } 1165 1166 if (ifname != NULL) 1167 *ifname = xstrdup(ifr.ifr_name); 1168 1169 close(sock); 1170 return fd; 1171 1172 failed: 1173 if (fd >= 0) 1174 close(fd); 1175 if (sock >= 0) 1176 close(sock); 1177 return -1; 1178 #else 1179 error("Tunnel interfaces are not supported on this platform"); 1180 return (-1); 1181 #endif 1182 } 1183 1184 void 1185 sanitise_stdfd(void) 1186 { 1187 int nullfd, dupfd; 1188 1189 if ((nullfd = dupfd = open(_PATH_DEVNULL, O_RDWR)) == -1) { 1190 fprintf(stderr, "Couldn't open /dev/null: %s\n", 1191 strerror(errno)); 1192 exit(1); 1193 } 1194 while (++dupfd <= STDERR_FILENO) { 1195 /* Only populate closed fds. */ 1196 if (fcntl(dupfd, F_GETFL) == -1 && errno == EBADF) { 1197 if (dup2(nullfd, dupfd) == -1) { 1198 fprintf(stderr, "dup2: %s\n", strerror(errno)); 1199 exit(1); 1200 } 1201 } 1202 } 1203 if (nullfd > STDERR_FILENO) 1204 close(nullfd); 1205 } 1206 1207 char * 1208 tohex(const void *vp, size_t l) 1209 { 1210 const u_char *p = (const u_char *)vp; 1211 char b[3], *r; 1212 size_t i, hl; 1213 1214 if (l > 65536) 1215 return xstrdup("tohex: length > 65536"); 1216 1217 hl = l * 2 + 1; 1218 r = xcalloc(1, hl); 1219 for (i = 0; i < l; i++) { 1220 snprintf(b, sizeof(b), "%02x", p[i]); 1221 strlcat(r, b, hl); 1222 } 1223 return (r); 1224 } 1225 1226 u_int64_t 1227 get_u64(const void *vp) 1228 { 1229 const u_char *p = (const u_char *)vp; 1230 u_int64_t v; 1231 1232 v = (u_int64_t)p[0] << 56; 1233 v |= (u_int64_t)p[1] << 48; 1234 v |= (u_int64_t)p[2] << 40; 1235 v |= (u_int64_t)p[3] << 32; 1236 v |= (u_int64_t)p[4] << 24; 1237 v |= (u_int64_t)p[5] << 16; 1238 v |= (u_int64_t)p[6] << 8; 1239 v |= (u_int64_t)p[7]; 1240 1241 return (v); 1242 } 1243 1244 u_int32_t 1245 get_u32(const void *vp) 1246 { 1247 const u_char *p = (const u_char *)vp; 1248 u_int32_t v; 1249 1250 v = (u_int32_t)p[0] << 24; 1251 v |= (u_int32_t)p[1] << 16; 1252 v |= (u_int32_t)p[2] << 8; 1253 v |= (u_int32_t)p[3]; 1254 1255 return (v); 1256 } 1257 1258 u_int32_t 1259 get_u32_le(const void *vp) 1260 { 1261 const u_char *p = (const u_char *)vp; 1262 u_int32_t v; 1263 1264 v = (u_int32_t)p[0]; 1265 v |= (u_int32_t)p[1] << 8; 1266 v |= (u_int32_t)p[2] << 16; 1267 v |= (u_int32_t)p[3] << 24; 1268 1269 return (v); 1270 } 1271 1272 u_int16_t 1273 get_u16(const void *vp) 1274 { 1275 const u_char *p = (const u_char *)vp; 1276 u_int16_t v; 1277 1278 v = (u_int16_t)p[0] << 8; 1279 v |= (u_int16_t)p[1]; 1280 1281 return (v); 1282 } 1283 1284 void 1285 put_u64(void *vp, u_int64_t v) 1286 { 1287 u_char *p = (u_char *)vp; 1288 1289 p[0] = (u_char)(v >> 56) & 0xff; 1290 p[1] = (u_char)(v >> 48) & 0xff; 1291 p[2] = (u_char)(v >> 40) & 0xff; 1292 p[3] = (u_char)(v >> 32) & 0xff; 1293 p[4] = (u_char)(v >> 24) & 0xff; 1294 p[5] = (u_char)(v >> 16) & 0xff; 1295 p[6] = (u_char)(v >> 8) & 0xff; 1296 p[7] = (u_char)v & 0xff; 1297 } 1298 1299 void 1300 put_u32(void *vp, u_int32_t v) 1301 { 1302 u_char *p = (u_char *)vp; 1303 1304 p[0] = (u_char)(v >> 24) & 0xff; 1305 p[1] = (u_char)(v >> 16) & 0xff; 1306 p[2] = (u_char)(v >> 8) & 0xff; 1307 p[3] = (u_char)v & 0xff; 1308 } 1309 1310 void 1311 put_u32_le(void *vp, u_int32_t v) 1312 { 1313 u_char *p = (u_char *)vp; 1314 1315 p[0] = (u_char)v & 0xff; 1316 p[1] = (u_char)(v >> 8) & 0xff; 1317 p[2] = (u_char)(v >> 16) & 0xff; 1318 p[3] = (u_char)(v >> 24) & 0xff; 1319 } 1320 1321 void 1322 put_u16(void *vp, u_int16_t v) 1323 { 1324 u_char *p = (u_char *)vp; 1325 1326 p[0] = (u_char)(v >> 8) & 0xff; 1327 p[1] = (u_char)v & 0xff; 1328 } 1329 1330 void 1331 ms_subtract_diff(struct timeval *start, int *ms) 1332 { 1333 struct timeval diff, finish; 1334 1335 monotime_tv(&finish); 1336 timersub(&finish, start, &diff); 1337 *ms -= (diff.tv_sec * 1000) + (diff.tv_usec / 1000); 1338 } 1339 1340 void 1341 ms_to_timeval(struct timeval *tv, int ms) 1342 { 1343 if (ms < 0) 1344 ms = 0; 1345 tv->tv_sec = ms / 1000; 1346 tv->tv_usec = (ms % 1000) * 1000; 1347 } 1348 1349 void 1350 monotime_ts(struct timespec *ts) 1351 { 1352 struct timeval tv; 1353 #if defined(HAVE_CLOCK_GETTIME) && (defined(CLOCK_BOOTTIME) || \ 1354 defined(CLOCK_MONOTONIC) || defined(CLOCK_REALTIME)) 1355 static int gettime_failed = 0; 1356 1357 if (!gettime_failed) { 1358 # ifdef CLOCK_BOOTTIME 1359 if (clock_gettime(CLOCK_BOOTTIME, ts) == 0) 1360 return; 1361 # endif /* CLOCK_BOOTTIME */ 1362 # ifdef CLOCK_MONOTONIC 1363 if (clock_gettime(CLOCK_MONOTONIC, ts) == 0) 1364 return; 1365 # endif /* CLOCK_MONOTONIC */ 1366 # ifdef CLOCK_REALTIME 1367 /* Not monotonic, but we're almost out of options here. */ 1368 if (clock_gettime(CLOCK_REALTIME, ts) == 0) 1369 return; 1370 # endif /* CLOCK_REALTIME */ 1371 debug3("clock_gettime: %s", strerror(errno)); 1372 gettime_failed = 1; 1373 } 1374 #endif /* HAVE_CLOCK_GETTIME && (BOOTTIME || MONOTONIC || REALTIME) */ 1375 gettimeofday(&tv, NULL); 1376 ts->tv_sec = tv.tv_sec; 1377 ts->tv_nsec = (long)tv.tv_usec * 1000; 1378 } 1379 1380 void 1381 monotime_tv(struct timeval *tv) 1382 { 1383 struct timespec ts; 1384 1385 monotime_ts(&ts); 1386 tv->tv_sec = ts.tv_sec; 1387 tv->tv_usec = ts.tv_nsec / 1000; 1388 } 1389 1390 time_t 1391 monotime(void) 1392 { 1393 struct timespec ts; 1394 1395 monotime_ts(&ts); 1396 return ts.tv_sec; 1397 } 1398 1399 double 1400 monotime_double(void) 1401 { 1402 struct timespec ts; 1403 1404 monotime_ts(&ts); 1405 return ts.tv_sec + ((double)ts.tv_nsec / 1000000000); 1406 } 1407 1408 void 1409 bandwidth_limit_init(struct bwlimit *bw, u_int64_t kbps, size_t buflen) 1410 { 1411 bw->buflen = buflen; 1412 bw->rate = kbps; 1413 bw->thresh = buflen; 1414 bw->lamt = 0; 1415 timerclear(&bw->bwstart); 1416 timerclear(&bw->bwend); 1417 } 1418 1419 /* Callback from read/write loop to insert bandwidth-limiting delays */ 1420 void 1421 bandwidth_limit(struct bwlimit *bw, size_t read_len) 1422 { 1423 u_int64_t waitlen; 1424 struct timespec ts, rm; 1425 1426 bw->lamt += read_len; 1427 if (!timerisset(&bw->bwstart)) { 1428 monotime_tv(&bw->bwstart); 1429 return; 1430 } 1431 if (bw->lamt < bw->thresh) 1432 return; 1433 1434 monotime_tv(&bw->bwend); 1435 timersub(&bw->bwend, &bw->bwstart, &bw->bwend); 1436 if (!timerisset(&bw->bwend)) 1437 return; 1438 1439 bw->lamt *= 8; 1440 waitlen = (double)1000000L * bw->lamt / bw->rate; 1441 1442 bw->bwstart.tv_sec = waitlen / 1000000L; 1443 bw->bwstart.tv_usec = waitlen % 1000000L; 1444 1445 if (timercmp(&bw->bwstart, &bw->bwend, >)) { 1446 timersub(&bw->bwstart, &bw->bwend, &bw->bwend); 1447 1448 /* Adjust the wait time */ 1449 if (bw->bwend.tv_sec) { 1450 bw->thresh /= 2; 1451 if (bw->thresh < bw->buflen / 4) 1452 bw->thresh = bw->buflen / 4; 1453 } else if (bw->bwend.tv_usec < 10000) { 1454 bw->thresh *= 2; 1455 if (bw->thresh > bw->buflen * 8) 1456 bw->thresh = bw->buflen * 8; 1457 } 1458 1459 TIMEVAL_TO_TIMESPEC(&bw->bwend, &ts); 1460 while (nanosleep(&ts, &rm) == -1) { 1461 if (errno != EINTR) 1462 break; 1463 ts = rm; 1464 } 1465 } 1466 1467 bw->lamt = 0; 1468 monotime_tv(&bw->bwstart); 1469 } 1470 1471 /* Make a template filename for mk[sd]temp() */ 1472 void 1473 mktemp_proto(char *s, size_t len) 1474 { 1475 const char *tmpdir; 1476 int r; 1477 1478 if ((tmpdir = getenv("TMPDIR")) != NULL) { 1479 r = snprintf(s, len, "%s/ssh-XXXXXXXXXXXX", tmpdir); 1480 if (r > 0 && (size_t)r < len) 1481 return; 1482 } 1483 r = snprintf(s, len, "/tmp/ssh-XXXXXXXXXXXX"); 1484 if (r < 0 || (size_t)r >= len) 1485 fatal("%s: template string too short", __func__); 1486 } 1487 1488 static const struct { 1489 const char *name; 1490 int value; 1491 } ipqos[] = { 1492 { "none", INT_MAX }, /* can't use 0 here; that's CS0 */ 1493 { "af11", IPTOS_DSCP_AF11 }, 1494 { "af12", IPTOS_DSCP_AF12 }, 1495 { "af13", IPTOS_DSCP_AF13 }, 1496 { "af21", IPTOS_DSCP_AF21 }, 1497 { "af22", IPTOS_DSCP_AF22 }, 1498 { "af23", IPTOS_DSCP_AF23 }, 1499 { "af31", IPTOS_DSCP_AF31 }, 1500 { "af32", IPTOS_DSCP_AF32 }, 1501 { "af33", IPTOS_DSCP_AF33 }, 1502 { "af41", IPTOS_DSCP_AF41 }, 1503 { "af42", IPTOS_DSCP_AF42 }, 1504 { "af43", IPTOS_DSCP_AF43 }, 1505 { "cs0", IPTOS_DSCP_CS0 }, 1506 { "cs1", IPTOS_DSCP_CS1 }, 1507 { "cs2", IPTOS_DSCP_CS2 }, 1508 { "cs3", IPTOS_DSCP_CS3 }, 1509 { "cs4", IPTOS_DSCP_CS4 }, 1510 { "cs5", IPTOS_DSCP_CS5 }, 1511 { "cs6", IPTOS_DSCP_CS6 }, 1512 { "cs7", IPTOS_DSCP_CS7 }, 1513 { "ef", IPTOS_DSCP_EF }, 1514 { "lowdelay", IPTOS_LOWDELAY }, 1515 { "throughput", IPTOS_THROUGHPUT }, 1516 { "reliability", IPTOS_RELIABILITY }, 1517 { NULL, -1 } 1518 }; 1519 1520 int 1521 parse_ipqos(const char *cp) 1522 { 1523 u_int i; 1524 char *ep; 1525 long val; 1526 1527 if (cp == NULL) 1528 return -1; 1529 for (i = 0; ipqos[i].name != NULL; i++) { 1530 if (strcasecmp(cp, ipqos[i].name) == 0) 1531 return ipqos[i].value; 1532 } 1533 /* Try parsing as an integer */ 1534 val = strtol(cp, &ep, 0); 1535 if (*cp == '\0' || *ep != '\0' || val < 0 || val > 255) 1536 return -1; 1537 return val; 1538 } 1539 1540 const char * 1541 iptos2str(int iptos) 1542 { 1543 int i; 1544 static char iptos_str[sizeof "0xff"]; 1545 1546 for (i = 0; ipqos[i].name != NULL; i++) { 1547 if (ipqos[i].value == iptos) 1548 return ipqos[i].name; 1549 } 1550 snprintf(iptos_str, sizeof iptos_str, "0x%02x", iptos); 1551 return iptos_str; 1552 } 1553 1554 void 1555 lowercase(char *s) 1556 { 1557 for (; *s; s++) 1558 *s = tolower((u_char)*s); 1559 } 1560 1561 int 1562 unix_listener(const char *path, int backlog, int unlink_first) 1563 { 1564 struct sockaddr_un sunaddr; 1565 int saved_errno, sock; 1566 1567 memset(&sunaddr, 0, sizeof(sunaddr)); 1568 sunaddr.sun_family = AF_UNIX; 1569 if (strlcpy(sunaddr.sun_path, path, 1570 sizeof(sunaddr.sun_path)) >= sizeof(sunaddr.sun_path)) { 1571 error("%s: path \"%s\" too long for Unix domain socket", 1572 __func__, path); 1573 errno = ENAMETOOLONG; 1574 return -1; 1575 } 1576 1577 sock = socket(PF_UNIX, SOCK_STREAM, 0); 1578 if (sock < 0) { 1579 saved_errno = errno; 1580 error("%s: socket: %.100s", __func__, strerror(errno)); 1581 errno = saved_errno; 1582 return -1; 1583 } 1584 if (unlink_first == 1) { 1585 if (unlink(path) != 0 && errno != ENOENT) 1586 error("unlink(%s): %.100s", path, strerror(errno)); 1587 } 1588 if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) < 0) { 1589 saved_errno = errno; 1590 error("%s: cannot bind to path %s: %s", 1591 __func__, path, strerror(errno)); 1592 close(sock); 1593 errno = saved_errno; 1594 return -1; 1595 } 1596 if (listen(sock, backlog) < 0) { 1597 saved_errno = errno; 1598 error("%s: cannot listen on path %s: %s", 1599 __func__, path, strerror(errno)); 1600 close(sock); 1601 unlink(path); 1602 errno = saved_errno; 1603 return -1; 1604 } 1605 return sock; 1606 } 1607 1608 void 1609 sock_set_v6only(int s) 1610 { 1611 #if defined(IPV6_V6ONLY) && !defined(__OpenBSD__) 1612 int on = 1; 1613 1614 debug3("%s: set socket %d IPV6_V6ONLY", __func__, s); 1615 if (setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) == -1) 1616 error("setsockopt IPV6_V6ONLY: %s", strerror(errno)); 1617 #endif 1618 } 1619 1620 /* 1621 * Compares two strings that maybe be NULL. Returns non-zero if strings 1622 * are both NULL or are identical, returns zero otherwise. 1623 */ 1624 static int 1625 strcmp_maybe_null(const char *a, const char *b) 1626 { 1627 if ((a == NULL && b != NULL) || (a != NULL && b == NULL)) 1628 return 0; 1629 if (a != NULL && strcmp(a, b) != 0) 1630 return 0; 1631 return 1; 1632 } 1633 1634 /* 1635 * Compare two forwards, returning non-zero if they are identical or 1636 * zero otherwise. 1637 */ 1638 int 1639 forward_equals(const struct Forward *a, const struct Forward *b) 1640 { 1641 if (strcmp_maybe_null(a->listen_host, b->listen_host) == 0) 1642 return 0; 1643 if (a->listen_port != b->listen_port) 1644 return 0; 1645 if (strcmp_maybe_null(a->listen_path, b->listen_path) == 0) 1646 return 0; 1647 if (strcmp_maybe_null(a->connect_host, b->connect_host) == 0) 1648 return 0; 1649 if (a->connect_port != b->connect_port) 1650 return 0; 1651 if (strcmp_maybe_null(a->connect_path, b->connect_path) == 0) 1652 return 0; 1653 /* allocated_port and handle are not checked */ 1654 return 1; 1655 } 1656 1657 /* returns 1 if process is already daemonized, 0 otherwise */ 1658 int 1659 daemonized(void) 1660 { 1661 int fd; 1662 1663 if ((fd = open(_PATH_TTY, O_RDONLY | O_NOCTTY)) >= 0) { 1664 close(fd); 1665 return 0; /* have controlling terminal */ 1666 } 1667 if (getppid() != 1) 1668 return 0; /* parent is not init */ 1669 if (getsid(0) != getpid()) 1670 return 0; /* not session leader */ 1671 debug3("already daemonized"); 1672 return 1; 1673 } 1674 1675 1676 /* 1677 * Splits 's' into an argument vector. Handles quoted string and basic 1678 * escape characters (\\, \", \'). Caller must free the argument vector 1679 * and its members. 1680 */ 1681 int 1682 argv_split(const char *s, int *argcp, char ***argvp) 1683 { 1684 int r = SSH_ERR_INTERNAL_ERROR; 1685 int argc = 0, quote, i, j; 1686 char *arg, **argv = xcalloc(1, sizeof(*argv)); 1687 1688 *argvp = NULL; 1689 *argcp = 0; 1690 1691 for (i = 0; s[i] != '\0'; i++) { 1692 /* Skip leading whitespace */ 1693 if (s[i] == ' ' || s[i] == '\t') 1694 continue; 1695 1696 /* Start of a token */ 1697 quote = 0; 1698 if (s[i] == '\\' && 1699 (s[i + 1] == '\'' || s[i + 1] == '\"' || s[i + 1] == '\\')) 1700 i++; 1701 else if (s[i] == '\'' || s[i] == '"') 1702 quote = s[i++]; 1703 1704 argv = xreallocarray(argv, (argc + 2), sizeof(*argv)); 1705 arg = argv[argc++] = xcalloc(1, strlen(s + i) + 1); 1706 argv[argc] = NULL; 1707 1708 /* Copy the token in, removing escapes */ 1709 for (j = 0; s[i] != '\0'; i++) { 1710 if (s[i] == '\\') { 1711 if (s[i + 1] == '\'' || 1712 s[i + 1] == '\"' || 1713 s[i + 1] == '\\') { 1714 i++; /* Skip '\' */ 1715 arg[j++] = s[i]; 1716 } else { 1717 /* Unrecognised escape */ 1718 arg[j++] = s[i]; 1719 } 1720 } else if (quote == 0 && (s[i] == ' ' || s[i] == '\t')) 1721 break; /* done */ 1722 else if (quote != 0 && s[i] == quote) 1723 break; /* done */ 1724 else 1725 arg[j++] = s[i]; 1726 } 1727 if (s[i] == '\0') { 1728 if (quote != 0) { 1729 /* Ran out of string looking for close quote */ 1730 r = SSH_ERR_INVALID_FORMAT; 1731 goto out; 1732 } 1733 break; 1734 } 1735 } 1736 /* Success */ 1737 *argcp = argc; 1738 *argvp = argv; 1739 argc = 0; 1740 argv = NULL; 1741 r = 0; 1742 out: 1743 if (argc != 0 && argv != NULL) { 1744 for (i = 0; i < argc; i++) 1745 free(argv[i]); 1746 free(argv); 1747 } 1748 return r; 1749 } 1750 1751 /* 1752 * Reassemble an argument vector into a string, quoting and escaping as 1753 * necessary. Caller must free returned string. 1754 */ 1755 char * 1756 argv_assemble(int argc, char **argv) 1757 { 1758 int i, j, ws, r; 1759 char c, *ret; 1760 struct sshbuf *buf, *arg; 1761 1762 if ((buf = sshbuf_new()) == NULL || (arg = sshbuf_new()) == NULL) 1763 fatal("%s: sshbuf_new failed", __func__); 1764 1765 for (i = 0; i < argc; i++) { 1766 ws = 0; 1767 sshbuf_reset(arg); 1768 for (j = 0; argv[i][j] != '\0'; j++) { 1769 r = 0; 1770 c = argv[i][j]; 1771 switch (c) { 1772 case ' ': 1773 case '\t': 1774 ws = 1; 1775 r = sshbuf_put_u8(arg, c); 1776 break; 1777 case '\\': 1778 case '\'': 1779 case '"': 1780 if ((r = sshbuf_put_u8(arg, '\\')) != 0) 1781 break; 1782 /* FALLTHROUGH */ 1783 default: 1784 r = sshbuf_put_u8(arg, c); 1785 break; 1786 } 1787 if (r != 0) 1788 fatal("%s: sshbuf_put_u8: %s", 1789 __func__, ssh_err(r)); 1790 } 1791 if ((i != 0 && (r = sshbuf_put_u8(buf, ' ')) != 0) || 1792 (ws != 0 && (r = sshbuf_put_u8(buf, '"')) != 0) || 1793 (r = sshbuf_putb(buf, arg)) != 0 || 1794 (ws != 0 && (r = sshbuf_put_u8(buf, '"')) != 0)) 1795 fatal("%s: buffer error: %s", __func__, ssh_err(r)); 1796 } 1797 if ((ret = malloc(sshbuf_len(buf) + 1)) == NULL) 1798 fatal("%s: malloc failed", __func__); 1799 memcpy(ret, sshbuf_ptr(buf), sshbuf_len(buf)); 1800 ret[sshbuf_len(buf)] = '\0'; 1801 sshbuf_free(buf); 1802 sshbuf_free(arg); 1803 return ret; 1804 } 1805 1806 /* Returns 0 if pid exited cleanly, non-zero otherwise */ 1807 int 1808 exited_cleanly(pid_t pid, const char *tag, const char *cmd, int quiet) 1809 { 1810 int status; 1811 1812 while (waitpid(pid, &status, 0) == -1) { 1813 if (errno != EINTR) { 1814 error("%s: waitpid: %s", tag, strerror(errno)); 1815 return -1; 1816 } 1817 } 1818 if (WIFSIGNALED(status)) { 1819 error("%s %s exited on signal %d", tag, cmd, WTERMSIG(status)); 1820 return -1; 1821 } else if (WEXITSTATUS(status) != 0) { 1822 do_log2(quiet ? SYSLOG_LEVEL_DEBUG1 : SYSLOG_LEVEL_INFO, 1823 "%s %s failed, status %d", tag, cmd, WEXITSTATUS(status)); 1824 return -1; 1825 } 1826 return 0; 1827 } 1828 1829 /* 1830 * Check a given path for security. This is defined as all components 1831 * of the path to the file must be owned by either the owner of 1832 * of the file or root and no directories must be group or world writable. 1833 * 1834 * XXX Should any specific check be done for sym links ? 1835 * 1836 * Takes a file name, its stat information (preferably from fstat() to 1837 * avoid races), the uid of the expected owner, their home directory and an 1838 * error buffer plus max size as arguments. 1839 * 1840 * Returns 0 on success and -1 on failure 1841 */ 1842 int 1843 safe_path(const char *name, struct stat *stp, const char *pw_dir, 1844 uid_t uid, char *err, size_t errlen) 1845 { 1846 char buf[PATH_MAX], homedir[PATH_MAX]; 1847 char *cp; 1848 int comparehome = 0; 1849 struct stat st; 1850 1851 if (realpath(name, buf) == NULL) { 1852 snprintf(err, errlen, "realpath %s failed: %s", name, 1853 strerror(errno)); 1854 return -1; 1855 } 1856 if (pw_dir != NULL && realpath(pw_dir, homedir) != NULL) 1857 comparehome = 1; 1858 1859 if (!S_ISREG(stp->st_mode)) { 1860 snprintf(err, errlen, "%s is not a regular file", buf); 1861 return -1; 1862 } 1863 if ((!platform_sys_dir_uid(stp->st_uid) && stp->st_uid != uid) || 1864 (stp->st_mode & 022) != 0) { 1865 snprintf(err, errlen, "bad ownership or modes for file %s", 1866 buf); 1867 return -1; 1868 } 1869 1870 /* for each component of the canonical path, walking upwards */ 1871 for (;;) { 1872 if ((cp = dirname(buf)) == NULL) { 1873 snprintf(err, errlen, "dirname() failed"); 1874 return -1; 1875 } 1876 strlcpy(buf, cp, sizeof(buf)); 1877 1878 if (stat(buf, &st) < 0 || 1879 (!platform_sys_dir_uid(st.st_uid) && st.st_uid != uid) || 1880 (st.st_mode & 022) != 0) { 1881 snprintf(err, errlen, 1882 "bad ownership or modes for directory %s", buf); 1883 return -1; 1884 } 1885 1886 /* If are past the homedir then we can stop */ 1887 if (comparehome && strcmp(homedir, buf) == 0) 1888 break; 1889 1890 /* 1891 * dirname should always complete with a "/" path, 1892 * but we can be paranoid and check for "." too 1893 */ 1894 if ((strcmp("/", buf) == 0) || (strcmp(".", buf) == 0)) 1895 break; 1896 } 1897 return 0; 1898 } 1899 1900 /* 1901 * Version of safe_path() that accepts an open file descriptor to 1902 * avoid races. 1903 * 1904 * Returns 0 on success and -1 on failure 1905 */ 1906 int 1907 safe_path_fd(int fd, const char *file, struct passwd *pw, 1908 char *err, size_t errlen) 1909 { 1910 struct stat st; 1911 1912 /* check the open file to avoid races */ 1913 if (fstat(fd, &st) < 0) { 1914 snprintf(err, errlen, "cannot stat file %s: %s", 1915 file, strerror(errno)); 1916 return -1; 1917 } 1918 return safe_path(file, &st, pw->pw_dir, pw->pw_uid, err, errlen); 1919 } 1920 1921 /* 1922 * Sets the value of the given variable in the environment. If the variable 1923 * already exists, its value is overridden. 1924 */ 1925 void 1926 child_set_env(char ***envp, u_int *envsizep, const char *name, 1927 const char *value) 1928 { 1929 char **env; 1930 u_int envsize; 1931 u_int i, namelen; 1932 1933 if (strchr(name, '=') != NULL) { 1934 error("Invalid environment variable \"%.100s\"", name); 1935 return; 1936 } 1937 1938 /* 1939 * If we're passed an uninitialized list, allocate a single null 1940 * entry before continuing. 1941 */ 1942 if (*envp == NULL && *envsizep == 0) { 1943 *envp = xmalloc(sizeof(char *)); 1944 *envp[0] = NULL; 1945 *envsizep = 1; 1946 } 1947 1948 /* 1949 * Find the slot where the value should be stored. If the variable 1950 * already exists, we reuse the slot; otherwise we append a new slot 1951 * at the end of the array, expanding if necessary. 1952 */ 1953 env = *envp; 1954 namelen = strlen(name); 1955 for (i = 0; env[i]; i++) 1956 if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=') 1957 break; 1958 if (env[i]) { 1959 /* Reuse the slot. */ 1960 free(env[i]); 1961 } else { 1962 /* New variable. Expand if necessary. */ 1963 envsize = *envsizep; 1964 if (i >= envsize - 1) { 1965 if (envsize >= 1000) 1966 fatal("child_set_env: too many env vars"); 1967 envsize += 50; 1968 env = (*envp) = xreallocarray(env, envsize, sizeof(char *)); 1969 *envsizep = envsize; 1970 } 1971 /* Need to set the NULL pointer at end of array beyond the new slot. */ 1972 env[i + 1] = NULL; 1973 } 1974 1975 /* Allocate space and format the variable in the appropriate slot. */ 1976 /* XXX xasprintf */ 1977 env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1); 1978 snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value); 1979 } 1980 1981 /* 1982 * Check and optionally lowercase a domain name, also removes trailing '.' 1983 * Returns 1 on success and 0 on failure, storing an error message in errstr. 1984 */ 1985 int 1986 valid_domain(char *name, int makelower, const char **errstr) 1987 { 1988 size_t i, l = strlen(name); 1989 u_char c, last = '\0'; 1990 static char errbuf[256]; 1991 1992 if (l == 0) { 1993 strlcpy(errbuf, "empty domain name", sizeof(errbuf)); 1994 goto bad; 1995 } 1996 if (!isalpha((u_char)name[0]) && !isdigit((u_char)name[0])) { 1997 snprintf(errbuf, sizeof(errbuf), "domain name \"%.100s\" " 1998 "starts with invalid character", name); 1999 goto bad; 2000 } 2001 for (i = 0; i < l; i++) { 2002 c = tolower((u_char)name[i]); 2003 if (makelower) 2004 name[i] = (char)c; 2005 if (last == '.' && c == '.') { 2006 snprintf(errbuf, sizeof(errbuf), "domain name " 2007 "\"%.100s\" contains consecutive separators", name); 2008 goto bad; 2009 } 2010 if (c != '.' && c != '-' && !isalnum(c) && 2011 c != '_') /* technically invalid, but common */ { 2012 snprintf(errbuf, sizeof(errbuf), "domain name " 2013 "\"%.100s\" contains invalid characters", name); 2014 goto bad; 2015 } 2016 last = c; 2017 } 2018 if (name[l - 1] == '.') 2019 name[l - 1] = '\0'; 2020 if (errstr != NULL) 2021 *errstr = NULL; 2022 return 1; 2023 bad: 2024 if (errstr != NULL) 2025 *errstr = errbuf; 2026 return 0; 2027 } 2028 2029 /* 2030 * Verify that a environment variable name (not including initial '$') is 2031 * valid; consisting of one or more alphanumeric or underscore characters only. 2032 * Returns 1 on valid, 0 otherwise. 2033 */ 2034 int 2035 valid_env_name(const char *name) 2036 { 2037 const char *cp; 2038 2039 if (name[0] == '\0') 2040 return 0; 2041 for (cp = name; *cp != '\0'; cp++) { 2042 if (!isalnum((u_char)*cp) && *cp != '_') 2043 return 0; 2044 } 2045 return 1; 2046 } 2047 2048 const char * 2049 atoi_err(const char *nptr, int *val) 2050 { 2051 const char *errstr = NULL; 2052 long long num; 2053 2054 if (nptr == NULL || *nptr == '\0') 2055 return "missing"; 2056 num = strtonum(nptr, 0, INT_MAX, &errstr); 2057 if (errstr == NULL) 2058 *val = (int)num; 2059 return errstr; 2060 } 2061 2062 int 2063 parse_absolute_time(const char *s, uint64_t *tp) 2064 { 2065 struct tm tm; 2066 time_t tt; 2067 char buf[32], *fmt; 2068 2069 *tp = 0; 2070 2071 /* 2072 * POSIX strptime says "The application shall ensure that there 2073 * is white-space or other non-alphanumeric characters between 2074 * any two conversion specifications" so arrange things this way. 2075 */ 2076 switch (strlen(s)) { 2077 case 8: /* YYYYMMDD */ 2078 fmt = "%Y-%m-%d"; 2079 snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2s", s, s + 4, s + 6); 2080 break; 2081 case 12: /* YYYYMMDDHHMM */ 2082 fmt = "%Y-%m-%dT%H:%M"; 2083 snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2sT%.2s:%.2s", 2084 s, s + 4, s + 6, s + 8, s + 10); 2085 break; 2086 case 14: /* YYYYMMDDHHMMSS */ 2087 fmt = "%Y-%m-%dT%H:%M:%S"; 2088 snprintf(buf, sizeof(buf), "%.4s-%.2s-%.2sT%.2s:%.2s:%.2s", 2089 s, s + 4, s + 6, s + 8, s + 10, s + 12); 2090 break; 2091 default: 2092 return SSH_ERR_INVALID_FORMAT; 2093 } 2094 2095 memset(&tm, 0, sizeof(tm)); 2096 if (strptime(buf, fmt, &tm) == NULL) 2097 return SSH_ERR_INVALID_FORMAT; 2098 if ((tt = mktime(&tm)) < 0) 2099 return SSH_ERR_INVALID_FORMAT; 2100 /* success */ 2101 *tp = (uint64_t)tt; 2102 return 0; 2103 } 2104 2105 void 2106 format_absolute_time(uint64_t t, char *buf, size_t len) 2107 { 2108 time_t tt = t > INT_MAX ? INT_MAX : t; /* XXX revisit in 2038 :P */ 2109 struct tm tm; 2110 2111 localtime_r(&tt, &tm); 2112 strftime(buf, len, "%Y-%m-%dT%H:%M:%S", &tm); 2113 } 2114 2115 /* check if path is absolute */ 2116 int 2117 path_absolute(const char *path) 2118 { 2119 return (*path == '/') ? 1 : 0; 2120 } 2121