1 /* 2 * Author: Tatu Ylonen <ylo@cs.hut.fi> 3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 4 * All rights reserved 5 * Functions for reading the configuration files. 6 * 7 * As far as I am concerned, the code I have written for this software 8 * can be used freely for any purpose. Any derived versions of this 9 * software must be clearly marked as such, and if the derived work is 10 * incompatible with the protocol description in the RFC file, it must be 11 * called by a name other than "ssh" or "Secure Shell". 12 */ 13 14 #include "includes.h" 15 RCSID("$OpenBSD: readconf.c,v 1.134 2004/07/11 17:48:47 deraadt Exp $"); 16 RCSID("$FreeBSD$"); 17 18 #include "ssh.h" 19 #include "xmalloc.h" 20 #include "compat.h" 21 #include "cipher.h" 22 #include "pathnames.h" 23 #include "log.h" 24 #include "readconf.h" 25 #include "match.h" 26 #include "misc.h" 27 #include "kex.h" 28 #include "mac.h" 29 30 /* Format of the configuration file: 31 32 # Configuration data is parsed as follows: 33 # 1. command line options 34 # 2. user-specific file 35 # 3. system-wide file 36 # Any configuration value is only changed the first time it is set. 37 # Thus, host-specific definitions should be at the beginning of the 38 # configuration file, and defaults at the end. 39 40 # Host-specific declarations. These may override anything above. A single 41 # host may match multiple declarations; these are processed in the order 42 # that they are given in. 43 44 Host *.ngs.fi ngs.fi 45 User foo 46 47 Host fake.com 48 HostName another.host.name.real.org 49 User blaah 50 Port 34289 51 ForwardX11 no 52 ForwardAgent no 53 54 Host books.com 55 RemoteForward 9999 shadows.cs.hut.fi:9999 56 Cipher 3des 57 58 Host fascist.blob.com 59 Port 23123 60 User tylonen 61 PasswordAuthentication no 62 63 Host puukko.hut.fi 64 User t35124p 65 ProxyCommand ssh-proxy %h %p 66 67 Host *.fr 68 PublicKeyAuthentication no 69 70 Host *.su 71 Cipher none 72 PasswordAuthentication no 73 74 # Defaults for various options 75 Host * 76 ForwardAgent no 77 ForwardX11 no 78 PasswordAuthentication yes 79 RSAAuthentication yes 80 RhostsRSAAuthentication yes 81 StrictHostKeyChecking yes 82 TcpKeepAlive no 83 IdentityFile ~/.ssh/identity 84 Port 22 85 EscapeChar ~ 86 87 */ 88 89 /* Keyword tokens. */ 90 91 typedef enum { 92 oBadOption, 93 oForwardAgent, oForwardX11, oForwardX11Trusted, oGatewayPorts, 94 oPasswordAuthentication, oRSAAuthentication, 95 oChallengeResponseAuthentication, oXAuthLocation, 96 oIdentityFile, oHostName, oPort, oCipher, oRemoteForward, oLocalForward, 97 oUser, oHost, oEscapeChar, oRhostsRSAAuthentication, oProxyCommand, 98 oGlobalKnownHostsFile, oUserKnownHostsFile, oConnectionAttempts, 99 oBatchMode, oCheckHostIP, oStrictHostKeyChecking, oCompression, 100 oCompressionLevel, oTCPKeepAlive, oNumberOfPasswordPrompts, 101 oUsePrivilegedPort, oLogLevel, oCiphers, oProtocol, oMacs, 102 oGlobalKnownHostsFile2, oUserKnownHostsFile2, oPubkeyAuthentication, 103 oKbdInteractiveAuthentication, oKbdInteractiveDevices, oHostKeyAlias, 104 oDynamicForward, oPreferredAuthentications, oHostbasedAuthentication, 105 oHostKeyAlgorithms, oBindAddress, oSmartcardDevice, 106 oClearAllForwardings, oNoHostAuthenticationForLocalhost, 107 oEnableSSHKeysign, oRekeyLimit, oVerifyHostKeyDNS, oConnectTimeout, 108 oAddressFamily, oGssAuthentication, oGssDelegateCreds, 109 oServerAliveInterval, oServerAliveCountMax, oIdentitiesOnly, 110 oSendEnv, oControlPath, oControlMaster, 111 oVersionAddendum, 112 oDeprecated, oUnsupported 113 } OpCodes; 114 115 /* Textual representations of the tokens. */ 116 117 static struct { 118 const char *name; 119 OpCodes opcode; 120 } keywords[] = { 121 { "forwardagent", oForwardAgent }, 122 { "forwardx11", oForwardX11 }, 123 { "forwardx11trusted", oForwardX11Trusted }, 124 { "xauthlocation", oXAuthLocation }, 125 { "gatewayports", oGatewayPorts }, 126 { "useprivilegedport", oUsePrivilegedPort }, 127 { "rhostsauthentication", oDeprecated }, 128 { "passwordauthentication", oPasswordAuthentication }, 129 { "kbdinteractiveauthentication", oKbdInteractiveAuthentication }, 130 { "kbdinteractivedevices", oKbdInteractiveDevices }, 131 { "rsaauthentication", oRSAAuthentication }, 132 { "pubkeyauthentication", oPubkeyAuthentication }, 133 { "dsaauthentication", oPubkeyAuthentication }, /* alias */ 134 { "rhostsrsaauthentication", oRhostsRSAAuthentication }, 135 { "hostbasedauthentication", oHostbasedAuthentication }, 136 { "challengeresponseauthentication", oChallengeResponseAuthentication }, 137 { "skeyauthentication", oChallengeResponseAuthentication }, /* alias */ 138 { "tisauthentication", oChallengeResponseAuthentication }, /* alias */ 139 { "kerberosauthentication", oUnsupported }, 140 { "kerberostgtpassing", oUnsupported }, 141 { "afstokenpassing", oUnsupported }, 142 #if defined(GSSAPI) 143 { "gssapiauthentication", oGssAuthentication }, 144 { "gssapidelegatecredentials", oGssDelegateCreds }, 145 #else 146 { "gssapiauthentication", oUnsupported }, 147 { "gssapidelegatecredentials", oUnsupported }, 148 #endif 149 { "fallbacktorsh", oDeprecated }, 150 { "usersh", oDeprecated }, 151 { "identityfile", oIdentityFile }, 152 { "identityfile2", oIdentityFile }, /* alias */ 153 { "identitiesonly", oIdentitiesOnly }, 154 { "hostname", oHostName }, 155 { "hostkeyalias", oHostKeyAlias }, 156 { "proxycommand", oProxyCommand }, 157 { "port", oPort }, 158 { "cipher", oCipher }, 159 { "ciphers", oCiphers }, 160 { "macs", oMacs }, 161 { "protocol", oProtocol }, 162 { "remoteforward", oRemoteForward }, 163 { "localforward", oLocalForward }, 164 { "user", oUser }, 165 { "host", oHost }, 166 { "escapechar", oEscapeChar }, 167 { "globalknownhostsfile", oGlobalKnownHostsFile }, 168 { "userknownhostsfile", oUserKnownHostsFile }, /* obsolete */ 169 { "globalknownhostsfile2", oGlobalKnownHostsFile2 }, 170 { "userknownhostsfile2", oUserKnownHostsFile2 }, /* obsolete */ 171 { "connectionattempts", oConnectionAttempts }, 172 { "batchmode", oBatchMode }, 173 { "checkhostip", oCheckHostIP }, 174 { "stricthostkeychecking", oStrictHostKeyChecking }, 175 { "compression", oCompression }, 176 { "compressionlevel", oCompressionLevel }, 177 { "tcpkeepalive", oTCPKeepAlive }, 178 { "keepalive", oTCPKeepAlive }, /* obsolete */ 179 { "numberofpasswordprompts", oNumberOfPasswordPrompts }, 180 { "loglevel", oLogLevel }, 181 { "dynamicforward", oDynamicForward }, 182 { "preferredauthentications", oPreferredAuthentications }, 183 { "hostkeyalgorithms", oHostKeyAlgorithms }, 184 { "bindaddress", oBindAddress }, 185 #ifdef SMARTCARD 186 { "smartcarddevice", oSmartcardDevice }, 187 #else 188 { "smartcarddevice", oUnsupported }, 189 #endif 190 { "clearallforwardings", oClearAllForwardings }, 191 { "enablesshkeysign", oEnableSSHKeysign }, 192 { "verifyhostkeydns", oVerifyHostKeyDNS }, 193 { "nohostauthenticationforlocalhost", oNoHostAuthenticationForLocalhost }, 194 { "rekeylimit", oRekeyLimit }, 195 { "connecttimeout", oConnectTimeout }, 196 { "addressfamily", oAddressFamily }, 197 { "serveraliveinterval", oServerAliveInterval }, 198 { "serveralivecountmax", oServerAliveCountMax }, 199 { "sendenv", oSendEnv }, 200 { "controlpath", oControlPath }, 201 { "controlmaster", oControlMaster }, 202 { "versionaddendum", oVersionAddendum }, 203 { NULL, oBadOption } 204 }; 205 206 /* 207 * Adds a local TCP/IP port forward to options. Never returns if there is an 208 * error. 209 */ 210 211 void 212 add_local_forward(Options *options, u_short port, const char *host, 213 u_short host_port) 214 { 215 Forward *fwd; 216 #ifndef NO_IPPORT_RESERVED_CONCEPT 217 extern uid_t original_real_uid; 218 if (port < IPPORT_RESERVED && original_real_uid != 0) 219 fatal("Privileged ports can only be forwarded by root."); 220 #endif 221 if (options->num_local_forwards >= SSH_MAX_FORWARDS_PER_DIRECTION) 222 fatal("Too many local forwards (max %d).", SSH_MAX_FORWARDS_PER_DIRECTION); 223 fwd = &options->local_forwards[options->num_local_forwards++]; 224 fwd->port = port; 225 fwd->host = xstrdup(host); 226 fwd->host_port = host_port; 227 } 228 229 /* 230 * Adds a remote TCP/IP port forward to options. Never returns if there is 231 * an error. 232 */ 233 234 void 235 add_remote_forward(Options *options, u_short port, const char *host, 236 u_short host_port) 237 { 238 Forward *fwd; 239 if (options->num_remote_forwards >= SSH_MAX_FORWARDS_PER_DIRECTION) 240 fatal("Too many remote forwards (max %d).", 241 SSH_MAX_FORWARDS_PER_DIRECTION); 242 fwd = &options->remote_forwards[options->num_remote_forwards++]; 243 fwd->port = port; 244 fwd->host = xstrdup(host); 245 fwd->host_port = host_port; 246 } 247 248 static void 249 clear_forwardings(Options *options) 250 { 251 int i; 252 253 for (i = 0; i < options->num_local_forwards; i++) 254 xfree(options->local_forwards[i].host); 255 options->num_local_forwards = 0; 256 for (i = 0; i < options->num_remote_forwards; i++) 257 xfree(options->remote_forwards[i].host); 258 options->num_remote_forwards = 0; 259 } 260 261 /* 262 * Returns the number of the token pointed to by cp or oBadOption. 263 */ 264 265 static OpCodes 266 parse_token(const char *cp, const char *filename, int linenum) 267 { 268 u_int i; 269 270 for (i = 0; keywords[i].name; i++) 271 if (strcasecmp(cp, keywords[i].name) == 0) 272 return keywords[i].opcode; 273 274 error("%s: line %d: Bad configuration option: %s", 275 filename, linenum, cp); 276 return oBadOption; 277 } 278 279 /* 280 * Processes a single option line as used in the configuration files. This 281 * only sets those values that have not already been set. 282 */ 283 #define WHITESPACE " \t\r\n" 284 285 int 286 process_config_line(Options *options, const char *host, 287 char *line, const char *filename, int linenum, 288 int *activep) 289 { 290 char buf[256], *s, **charptr, *endofnumber, *keyword, *arg; 291 int opcode, *intptr, value; 292 size_t len; 293 u_short fwd_port, fwd_host_port; 294 char sfwd_host_port[6]; 295 296 /* Strip trailing whitespace */ 297 for(len = strlen(line) - 1; len > 0; len--) { 298 if (strchr(WHITESPACE, line[len]) == NULL) 299 break; 300 line[len] = '\0'; 301 } 302 303 s = line; 304 /* Get the keyword. (Each line is supposed to begin with a keyword). */ 305 keyword = strdelim(&s); 306 /* Ignore leading whitespace. */ 307 if (*keyword == '\0') 308 keyword = strdelim(&s); 309 if (keyword == NULL || !*keyword || *keyword == '\n' || *keyword == '#') 310 return 0; 311 312 opcode = parse_token(keyword, filename, linenum); 313 314 switch (opcode) { 315 case oBadOption: 316 /* don't panic, but count bad options */ 317 return -1; 318 /* NOTREACHED */ 319 case oConnectTimeout: 320 intptr = &options->connection_timeout; 321 parse_time: 322 arg = strdelim(&s); 323 if (!arg || *arg == '\0') 324 fatal("%s line %d: missing time value.", 325 filename, linenum); 326 if ((value = convtime(arg)) == -1) 327 fatal("%s line %d: invalid time value.", 328 filename, linenum); 329 if (*intptr == -1) 330 *intptr = value; 331 break; 332 333 case oForwardAgent: 334 intptr = &options->forward_agent; 335 parse_flag: 336 arg = strdelim(&s); 337 if (!arg || *arg == '\0') 338 fatal("%.200s line %d: Missing yes/no argument.", filename, linenum); 339 value = 0; /* To avoid compiler warning... */ 340 if (strcmp(arg, "yes") == 0 || strcmp(arg, "true") == 0) 341 value = 1; 342 else if (strcmp(arg, "no") == 0 || strcmp(arg, "false") == 0) 343 value = 0; 344 else 345 fatal("%.200s line %d: Bad yes/no argument.", filename, linenum); 346 if (*activep && *intptr == -1) 347 *intptr = value; 348 break; 349 350 case oForwardX11: 351 intptr = &options->forward_x11; 352 goto parse_flag; 353 354 case oForwardX11Trusted: 355 intptr = &options->forward_x11_trusted; 356 goto parse_flag; 357 358 case oGatewayPorts: 359 intptr = &options->gateway_ports; 360 goto parse_flag; 361 362 case oUsePrivilegedPort: 363 intptr = &options->use_privileged_port; 364 goto parse_flag; 365 366 case oPasswordAuthentication: 367 intptr = &options->password_authentication; 368 goto parse_flag; 369 370 case oKbdInteractiveAuthentication: 371 intptr = &options->kbd_interactive_authentication; 372 goto parse_flag; 373 374 case oKbdInteractiveDevices: 375 charptr = &options->kbd_interactive_devices; 376 goto parse_string; 377 378 case oPubkeyAuthentication: 379 intptr = &options->pubkey_authentication; 380 goto parse_flag; 381 382 case oRSAAuthentication: 383 intptr = &options->rsa_authentication; 384 goto parse_flag; 385 386 case oRhostsRSAAuthentication: 387 intptr = &options->rhosts_rsa_authentication; 388 goto parse_flag; 389 390 case oHostbasedAuthentication: 391 intptr = &options->hostbased_authentication; 392 goto parse_flag; 393 394 case oChallengeResponseAuthentication: 395 intptr = &options->challenge_response_authentication; 396 goto parse_flag; 397 398 case oGssAuthentication: 399 intptr = &options->gss_authentication; 400 goto parse_flag; 401 402 case oGssDelegateCreds: 403 intptr = &options->gss_deleg_creds; 404 goto parse_flag; 405 406 case oBatchMode: 407 intptr = &options->batch_mode; 408 goto parse_flag; 409 410 case oCheckHostIP: 411 intptr = &options->check_host_ip; 412 goto parse_flag; 413 414 case oVerifyHostKeyDNS: 415 intptr = &options->verify_host_key_dns; 416 goto parse_yesnoask; 417 418 case oStrictHostKeyChecking: 419 intptr = &options->strict_host_key_checking; 420 parse_yesnoask: 421 arg = strdelim(&s); 422 if (!arg || *arg == '\0') 423 fatal("%.200s line %d: Missing yes/no/ask argument.", 424 filename, linenum); 425 value = 0; /* To avoid compiler warning... */ 426 if (strcmp(arg, "yes") == 0 || strcmp(arg, "true") == 0) 427 value = 1; 428 else if (strcmp(arg, "no") == 0 || strcmp(arg, "false") == 0) 429 value = 0; 430 else if (strcmp(arg, "ask") == 0) 431 value = 2; 432 else 433 fatal("%.200s line %d: Bad yes/no/ask argument.", filename, linenum); 434 if (*activep && *intptr == -1) 435 *intptr = value; 436 break; 437 438 case oCompression: 439 intptr = &options->compression; 440 goto parse_flag; 441 442 case oTCPKeepAlive: 443 intptr = &options->tcp_keep_alive; 444 goto parse_flag; 445 446 case oNoHostAuthenticationForLocalhost: 447 intptr = &options->no_host_authentication_for_localhost; 448 goto parse_flag; 449 450 case oNumberOfPasswordPrompts: 451 intptr = &options->number_of_password_prompts; 452 goto parse_int; 453 454 case oCompressionLevel: 455 intptr = &options->compression_level; 456 goto parse_int; 457 458 case oRekeyLimit: 459 intptr = &options->rekey_limit; 460 arg = strdelim(&s); 461 if (!arg || *arg == '\0') 462 fatal("%.200s line %d: Missing argument.", filename, linenum); 463 if (arg[0] < '0' || arg[0] > '9') 464 fatal("%.200s line %d: Bad number.", filename, linenum); 465 value = strtol(arg, &endofnumber, 10); 466 if (arg == endofnumber) 467 fatal("%.200s line %d: Bad number.", filename, linenum); 468 switch (toupper(*endofnumber)) { 469 case 'K': 470 value *= 1<<10; 471 break; 472 case 'M': 473 value *= 1<<20; 474 break; 475 case 'G': 476 value *= 1<<30; 477 break; 478 } 479 if (*activep && *intptr == -1) 480 *intptr = value; 481 break; 482 483 case oIdentityFile: 484 arg = strdelim(&s); 485 if (!arg || *arg == '\0') 486 fatal("%.200s line %d: Missing argument.", filename, linenum); 487 if (*activep) { 488 intptr = &options->num_identity_files; 489 if (*intptr >= SSH_MAX_IDENTITY_FILES) 490 fatal("%.200s line %d: Too many identity files specified (max %d).", 491 filename, linenum, SSH_MAX_IDENTITY_FILES); 492 charptr = &options->identity_files[*intptr]; 493 *charptr = xstrdup(arg); 494 *intptr = *intptr + 1; 495 } 496 break; 497 498 case oXAuthLocation: 499 charptr=&options->xauth_location; 500 goto parse_string; 501 502 case oUser: 503 charptr = &options->user; 504 parse_string: 505 arg = strdelim(&s); 506 if (!arg || *arg == '\0') 507 fatal("%.200s line %d: Missing argument.", filename, linenum); 508 if (*activep && *charptr == NULL) 509 *charptr = xstrdup(arg); 510 break; 511 512 case oGlobalKnownHostsFile: 513 charptr = &options->system_hostfile; 514 goto parse_string; 515 516 case oUserKnownHostsFile: 517 charptr = &options->user_hostfile; 518 goto parse_string; 519 520 case oGlobalKnownHostsFile2: 521 charptr = &options->system_hostfile2; 522 goto parse_string; 523 524 case oUserKnownHostsFile2: 525 charptr = &options->user_hostfile2; 526 goto parse_string; 527 528 case oHostName: 529 charptr = &options->hostname; 530 goto parse_string; 531 532 case oHostKeyAlias: 533 charptr = &options->host_key_alias; 534 goto parse_string; 535 536 case oPreferredAuthentications: 537 charptr = &options->preferred_authentications; 538 goto parse_string; 539 540 case oBindAddress: 541 charptr = &options->bind_address; 542 goto parse_string; 543 544 case oSmartcardDevice: 545 charptr = &options->smartcard_device; 546 goto parse_string; 547 548 case oProxyCommand: 549 if (s == NULL) 550 fatal("%.200s line %d: Missing argument.", filename, linenum); 551 charptr = &options->proxy_command; 552 len = strspn(s, WHITESPACE "="); 553 if (*activep && *charptr == NULL) 554 *charptr = xstrdup(s + len); 555 return 0; 556 557 case oPort: 558 intptr = &options->port; 559 parse_int: 560 arg = strdelim(&s); 561 if (!arg || *arg == '\0') 562 fatal("%.200s line %d: Missing argument.", filename, linenum); 563 if (arg[0] < '0' || arg[0] > '9') 564 fatal("%.200s line %d: Bad number.", filename, linenum); 565 566 /* Octal, decimal, or hex format? */ 567 value = strtol(arg, &endofnumber, 0); 568 if (arg == endofnumber) 569 fatal("%.200s line %d: Bad number.", filename, linenum); 570 if (*activep && *intptr == -1) 571 *intptr = value; 572 break; 573 574 case oConnectionAttempts: 575 intptr = &options->connection_attempts; 576 goto parse_int; 577 578 case oCipher: 579 intptr = &options->cipher; 580 arg = strdelim(&s); 581 if (!arg || *arg == '\0') 582 fatal("%.200s line %d: Missing argument.", filename, linenum); 583 value = cipher_number(arg); 584 if (value == -1) 585 fatal("%.200s line %d: Bad cipher '%s'.", 586 filename, linenum, arg ? arg : "<NONE>"); 587 if (*activep && *intptr == -1) 588 *intptr = value; 589 break; 590 591 case oCiphers: 592 arg = strdelim(&s); 593 if (!arg || *arg == '\0') 594 fatal("%.200s line %d: Missing argument.", filename, linenum); 595 if (!ciphers_valid(arg)) 596 fatal("%.200s line %d: Bad SSH2 cipher spec '%s'.", 597 filename, linenum, arg ? arg : "<NONE>"); 598 if (*activep && options->ciphers == NULL) 599 options->ciphers = xstrdup(arg); 600 break; 601 602 case oMacs: 603 arg = strdelim(&s); 604 if (!arg || *arg == '\0') 605 fatal("%.200s line %d: Missing argument.", filename, linenum); 606 if (!mac_valid(arg)) 607 fatal("%.200s line %d: Bad SSH2 Mac spec '%s'.", 608 filename, linenum, arg ? arg : "<NONE>"); 609 if (*activep && options->macs == NULL) 610 options->macs = xstrdup(arg); 611 break; 612 613 case oHostKeyAlgorithms: 614 arg = strdelim(&s); 615 if (!arg || *arg == '\0') 616 fatal("%.200s line %d: Missing argument.", filename, linenum); 617 if (!key_names_valid2(arg)) 618 fatal("%.200s line %d: Bad protocol 2 host key algorithms '%s'.", 619 filename, linenum, arg ? arg : "<NONE>"); 620 if (*activep && options->hostkeyalgorithms == NULL) 621 options->hostkeyalgorithms = xstrdup(arg); 622 break; 623 624 case oProtocol: 625 intptr = &options->protocol; 626 arg = strdelim(&s); 627 if (!arg || *arg == '\0') 628 fatal("%.200s line %d: Missing argument.", filename, linenum); 629 value = proto_spec(arg); 630 if (value == SSH_PROTO_UNKNOWN) 631 fatal("%.200s line %d: Bad protocol spec '%s'.", 632 filename, linenum, arg ? arg : "<NONE>"); 633 if (*activep && *intptr == SSH_PROTO_UNKNOWN) 634 *intptr = value; 635 break; 636 637 case oLogLevel: 638 intptr = (int *) &options->log_level; 639 arg = strdelim(&s); 640 value = log_level_number(arg); 641 if (value == SYSLOG_LEVEL_NOT_SET) 642 fatal("%.200s line %d: unsupported log level '%s'", 643 filename, linenum, arg ? arg : "<NONE>"); 644 if (*activep && (LogLevel) *intptr == SYSLOG_LEVEL_NOT_SET) 645 *intptr = (LogLevel) value; 646 break; 647 648 case oLocalForward: 649 case oRemoteForward: 650 arg = strdelim(&s); 651 if (!arg || *arg == '\0') 652 fatal("%.200s line %d: Missing port argument.", 653 filename, linenum); 654 if ((fwd_port = a2port(arg)) == 0) 655 fatal("%.200s line %d: Bad listen port.", 656 filename, linenum); 657 arg = strdelim(&s); 658 if (!arg || *arg == '\0') 659 fatal("%.200s line %d: Missing second argument.", 660 filename, linenum); 661 if (sscanf(arg, "%255[^:]:%5[0-9]", buf, sfwd_host_port) != 2 && 662 sscanf(arg, "%255[^/]/%5[0-9]", buf, sfwd_host_port) != 2) 663 fatal("%.200s line %d: Bad forwarding specification.", 664 filename, linenum); 665 if ((fwd_host_port = a2port(sfwd_host_port)) == 0) 666 fatal("%.200s line %d: Bad forwarding port.", 667 filename, linenum); 668 if (*activep) { 669 if (opcode == oLocalForward) 670 add_local_forward(options, fwd_port, buf, 671 fwd_host_port); 672 else if (opcode == oRemoteForward) 673 add_remote_forward(options, fwd_port, buf, 674 fwd_host_port); 675 } 676 break; 677 678 case oDynamicForward: 679 arg = strdelim(&s); 680 if (!arg || *arg == '\0') 681 fatal("%.200s line %d: Missing port argument.", 682 filename, linenum); 683 fwd_port = a2port(arg); 684 if (fwd_port == 0) 685 fatal("%.200s line %d: Badly formatted port number.", 686 filename, linenum); 687 if (*activep) 688 add_local_forward(options, fwd_port, "socks", 0); 689 break; 690 691 case oClearAllForwardings: 692 intptr = &options->clear_forwardings; 693 goto parse_flag; 694 695 case oHost: 696 *activep = 0; 697 while ((arg = strdelim(&s)) != NULL && *arg != '\0') 698 if (match_pattern(host, arg)) { 699 debug("Applying options for %.100s", arg); 700 *activep = 1; 701 break; 702 } 703 /* Avoid garbage check below, as strdelim is done. */ 704 return 0; 705 706 case oEscapeChar: 707 intptr = &options->escape_char; 708 arg = strdelim(&s); 709 if (!arg || *arg == '\0') 710 fatal("%.200s line %d: Missing argument.", filename, linenum); 711 if (arg[0] == '^' && arg[2] == 0 && 712 (u_char) arg[1] >= 64 && (u_char) arg[1] < 128) 713 value = (u_char) arg[1] & 31; 714 else if (strlen(arg) == 1) 715 value = (u_char) arg[0]; 716 else if (strcmp(arg, "none") == 0) 717 value = SSH_ESCAPECHAR_NONE; 718 else { 719 fatal("%.200s line %d: Bad escape character.", 720 filename, linenum); 721 /* NOTREACHED */ 722 value = 0; /* Avoid compiler warning. */ 723 } 724 if (*activep && *intptr == -1) 725 *intptr = value; 726 break; 727 728 case oAddressFamily: 729 arg = strdelim(&s); 730 intptr = &options->address_family; 731 if (strcasecmp(arg, "inet") == 0) 732 value = AF_INET; 733 else if (strcasecmp(arg, "inet6") == 0) 734 value = AF_INET6; 735 else if (strcasecmp(arg, "any") == 0) 736 value = AF_UNSPEC; 737 else 738 fatal("Unsupported AddressFamily \"%s\"", arg); 739 if (*activep && *intptr == -1) 740 *intptr = value; 741 break; 742 743 case oEnableSSHKeysign: 744 intptr = &options->enable_ssh_keysign; 745 goto parse_flag; 746 747 case oIdentitiesOnly: 748 intptr = &options->identities_only; 749 goto parse_flag; 750 751 case oServerAliveInterval: 752 intptr = &options->server_alive_interval; 753 goto parse_time; 754 755 case oServerAliveCountMax: 756 intptr = &options->server_alive_count_max; 757 goto parse_int; 758 759 case oSendEnv: 760 while ((arg = strdelim(&s)) != NULL && *arg != '\0') { 761 if (strchr(arg, '=') != NULL) 762 fatal("%s line %d: Invalid environment name.", 763 filename, linenum); 764 if (options->num_send_env >= MAX_SEND_ENV) 765 fatal("%s line %d: too many send env.", 766 filename, linenum); 767 options->send_env[options->num_send_env++] = 768 xstrdup(arg); 769 } 770 break; 771 772 case oControlPath: 773 charptr = &options->control_path; 774 goto parse_string; 775 776 case oControlMaster: 777 intptr = &options->control_master; 778 goto parse_yesnoask; 779 780 case oVersionAddendum: 781 ssh_version_set_addendum(strtok(s, "\n")); 782 do { 783 arg = strdelim(&s); 784 } while (arg != NULL && *arg != '\0'); 785 break; 786 787 case oDeprecated: 788 debug("%s line %d: Deprecated option \"%s\"", 789 filename, linenum, keyword); 790 return 0; 791 792 case oUnsupported: 793 error("%s line %d: Unsupported option \"%s\"", 794 filename, linenum, keyword); 795 return 0; 796 797 default: 798 fatal("process_config_line: Unimplemented opcode %d", opcode); 799 } 800 801 /* Check that there is no garbage at end of line. */ 802 if ((arg = strdelim(&s)) != NULL && *arg != '\0') { 803 fatal("%.200s line %d: garbage at end of line; \"%.200s\".", 804 filename, linenum, arg); 805 } 806 return 0; 807 } 808 809 810 /* 811 * Reads the config file and modifies the options accordingly. Options 812 * should already be initialized before this call. This never returns if 813 * there is an error. If the file does not exist, this returns 0. 814 */ 815 816 int 817 read_config_file(const char *filename, const char *host, Options *options, 818 int checkperm) 819 { 820 FILE *f; 821 char line[1024]; 822 int active, linenum; 823 int bad_options = 0; 824 825 /* Open the file. */ 826 if ((f = fopen(filename, "r")) == NULL) 827 return 0; 828 829 if (checkperm) { 830 struct stat sb; 831 832 if (fstat(fileno(f), &sb) == -1) 833 fatal("fstat %s: %s", filename, strerror(errno)); 834 if (((sb.st_uid != 0 && sb.st_uid != getuid()) || 835 (sb.st_mode & 022) != 0)) 836 fatal("Bad owner or permissions on %s", filename); 837 } 838 839 debug("Reading configuration data %.200s", filename); 840 841 /* 842 * Mark that we are now processing the options. This flag is turned 843 * on/off by Host specifications. 844 */ 845 active = 1; 846 linenum = 0; 847 while (fgets(line, sizeof(line), f)) { 848 /* Update line number counter. */ 849 linenum++; 850 if (process_config_line(options, host, line, filename, linenum, &active) != 0) 851 bad_options++; 852 } 853 fclose(f); 854 if (bad_options > 0) 855 fatal("%s: terminating, %d bad configuration options", 856 filename, bad_options); 857 return 1; 858 } 859 860 /* 861 * Initializes options to special values that indicate that they have not yet 862 * been set. Read_config_file will only set options with this value. Options 863 * are processed in the following order: command line, user config file, 864 * system config file. Last, fill_default_options is called. 865 */ 866 867 void 868 initialize_options(Options * options) 869 { 870 memset(options, 'X', sizeof(*options)); 871 options->forward_agent = -1; 872 options->forward_x11 = -1; 873 options->forward_x11_trusted = -1; 874 options->xauth_location = NULL; 875 options->gateway_ports = -1; 876 options->use_privileged_port = -1; 877 options->rsa_authentication = -1; 878 options->pubkey_authentication = -1; 879 options->challenge_response_authentication = -1; 880 options->gss_authentication = -1; 881 options->gss_deleg_creds = -1; 882 options->password_authentication = -1; 883 options->kbd_interactive_authentication = -1; 884 options->kbd_interactive_devices = NULL; 885 options->rhosts_rsa_authentication = -1; 886 options->hostbased_authentication = -1; 887 options->batch_mode = -1; 888 options->check_host_ip = -1; 889 options->strict_host_key_checking = -1; 890 options->compression = -1; 891 options->tcp_keep_alive = -1; 892 options->compression_level = -1; 893 options->port = -1; 894 options->address_family = -1; 895 options->connection_attempts = -1; 896 options->connection_timeout = -1; 897 options->number_of_password_prompts = -1; 898 options->cipher = -1; 899 options->ciphers = NULL; 900 options->macs = NULL; 901 options->hostkeyalgorithms = NULL; 902 options->protocol = SSH_PROTO_UNKNOWN; 903 options->num_identity_files = 0; 904 options->hostname = NULL; 905 options->host_key_alias = NULL; 906 options->proxy_command = NULL; 907 options->user = NULL; 908 options->escape_char = -1; 909 options->system_hostfile = NULL; 910 options->user_hostfile = NULL; 911 options->system_hostfile2 = NULL; 912 options->user_hostfile2 = NULL; 913 options->num_local_forwards = 0; 914 options->num_remote_forwards = 0; 915 options->clear_forwardings = -1; 916 options->log_level = SYSLOG_LEVEL_NOT_SET; 917 options->preferred_authentications = NULL; 918 options->bind_address = NULL; 919 options->smartcard_device = NULL; 920 options->enable_ssh_keysign = - 1; 921 options->no_host_authentication_for_localhost = - 1; 922 options->identities_only = - 1; 923 options->rekey_limit = - 1; 924 options->verify_host_key_dns = -1; 925 options->server_alive_interval = -1; 926 options->server_alive_count_max = -1; 927 options->num_send_env = 0; 928 options->control_path = NULL; 929 options->control_master = -1; 930 } 931 932 /* 933 * Called after processing other sources of option data, this fills those 934 * options for which no value has been specified with their default values. 935 */ 936 937 void 938 fill_default_options(Options * options) 939 { 940 int len; 941 942 if (options->forward_agent == -1) 943 options->forward_agent = 0; 944 if (options->forward_x11 == -1) 945 options->forward_x11 = 0; 946 if (options->forward_x11_trusted == -1) 947 options->forward_x11_trusted = 0; 948 if (options->xauth_location == NULL) 949 options->xauth_location = _PATH_XAUTH; 950 if (options->gateway_ports == -1) 951 options->gateway_ports = 0; 952 if (options->use_privileged_port == -1) 953 options->use_privileged_port = 0; 954 if (options->rsa_authentication == -1) 955 options->rsa_authentication = 1; 956 if (options->pubkey_authentication == -1) 957 options->pubkey_authentication = 1; 958 if (options->challenge_response_authentication == -1) 959 options->challenge_response_authentication = 1; 960 if (options->gss_authentication == -1) 961 options->gss_authentication = 0; 962 if (options->gss_deleg_creds == -1) 963 options->gss_deleg_creds = 0; 964 if (options->password_authentication == -1) 965 options->password_authentication = 1; 966 if (options->kbd_interactive_authentication == -1) 967 options->kbd_interactive_authentication = 1; 968 if (options->rhosts_rsa_authentication == -1) 969 options->rhosts_rsa_authentication = 0; 970 if (options->hostbased_authentication == -1) 971 options->hostbased_authentication = 0; 972 if (options->batch_mode == -1) 973 options->batch_mode = 0; 974 if (options->check_host_ip == -1) 975 options->check_host_ip = 0; 976 if (options->strict_host_key_checking == -1) 977 options->strict_host_key_checking = 2; /* 2 is default */ 978 if (options->compression == -1) 979 options->compression = 0; 980 if (options->tcp_keep_alive == -1) 981 options->tcp_keep_alive = 1; 982 if (options->compression_level == -1) 983 options->compression_level = 6; 984 if (options->port == -1) 985 options->port = 0; /* Filled in ssh_connect. */ 986 if (options->address_family == -1) 987 options->address_family = AF_UNSPEC; 988 if (options->connection_attempts == -1) 989 options->connection_attempts = 1; 990 if (options->number_of_password_prompts == -1) 991 options->number_of_password_prompts = 3; 992 /* Selected in ssh_login(). */ 993 if (options->cipher == -1) 994 options->cipher = SSH_CIPHER_NOT_SET; 995 /* options->ciphers, default set in myproposals.h */ 996 /* options->macs, default set in myproposals.h */ 997 /* options->hostkeyalgorithms, default set in myproposals.h */ 998 if (options->protocol == SSH_PROTO_UNKNOWN) 999 options->protocol = SSH_PROTO_1|SSH_PROTO_2; 1000 if (options->num_identity_files == 0) { 1001 if (options->protocol & SSH_PROTO_1) { 1002 len = 2 + strlen(_PATH_SSH_CLIENT_IDENTITY) + 1; 1003 options->identity_files[options->num_identity_files] = 1004 xmalloc(len); 1005 snprintf(options->identity_files[options->num_identity_files++], 1006 len, "~/%.100s", _PATH_SSH_CLIENT_IDENTITY); 1007 } 1008 if (options->protocol & SSH_PROTO_2) { 1009 len = 2 + strlen(_PATH_SSH_CLIENT_ID_RSA) + 1; 1010 options->identity_files[options->num_identity_files] = 1011 xmalloc(len); 1012 snprintf(options->identity_files[options->num_identity_files++], 1013 len, "~/%.100s", _PATH_SSH_CLIENT_ID_RSA); 1014 1015 len = 2 + strlen(_PATH_SSH_CLIENT_ID_DSA) + 1; 1016 options->identity_files[options->num_identity_files] = 1017 xmalloc(len); 1018 snprintf(options->identity_files[options->num_identity_files++], 1019 len, "~/%.100s", _PATH_SSH_CLIENT_ID_DSA); 1020 } 1021 } 1022 if (options->escape_char == -1) 1023 options->escape_char = '~'; 1024 if (options->system_hostfile == NULL) 1025 options->system_hostfile = _PATH_SSH_SYSTEM_HOSTFILE; 1026 if (options->user_hostfile == NULL) 1027 options->user_hostfile = _PATH_SSH_USER_HOSTFILE; 1028 if (options->system_hostfile2 == NULL) 1029 options->system_hostfile2 = _PATH_SSH_SYSTEM_HOSTFILE2; 1030 if (options->user_hostfile2 == NULL) 1031 options->user_hostfile2 = _PATH_SSH_USER_HOSTFILE2; 1032 if (options->log_level == SYSLOG_LEVEL_NOT_SET) 1033 options->log_level = SYSLOG_LEVEL_INFO; 1034 if (options->clear_forwardings == 1) 1035 clear_forwardings(options); 1036 if (options->no_host_authentication_for_localhost == - 1) 1037 options->no_host_authentication_for_localhost = 0; 1038 if (options->identities_only == -1) 1039 options->identities_only = 0; 1040 if (options->enable_ssh_keysign == -1) 1041 options->enable_ssh_keysign = 0; 1042 if (options->rekey_limit == -1) 1043 options->rekey_limit = 0; 1044 if (options->verify_host_key_dns == -1) 1045 options->verify_host_key_dns = 0; 1046 if (options->server_alive_interval == -1) 1047 options->server_alive_interval = 0; 1048 if (options->server_alive_count_max == -1) 1049 options->server_alive_count_max = 3; 1050 if (options->control_master == -1) 1051 options->control_master = 0; 1052 /* options->proxy_command should not be set by default */ 1053 /* options->user will be set in the main program if appropriate */ 1054 /* options->hostname will be set in the main program if appropriate */ 1055 /* options->host_key_alias should not be set by default */ 1056 /* options->preferred_authentications will be set in ssh */ 1057 } 1058