1 /* 2 * Copyright (c) 2000-2005 Sendmail, Inc. and its suppliers. 3 * All rights reserved. 4 * 5 * By using this file, you agree to the terms and conditions set 6 * forth in the LICENSE file which can be found at the top level of 7 * the sendmail distribution. 8 * 9 */ 10 11 #include <sendmail.h> 12 13 SM_RCSID("@(#)$Id: tls.c,v 8.102 2006/03/02 19:18:27 ca Exp $") 14 15 #if STARTTLS 16 # include <openssl/err.h> 17 # include <openssl/bio.h> 18 # include <openssl/pem.h> 19 # ifndef HASURANDOMDEV 20 # include <openssl/rand.h> 21 # endif /* ! HASURANDOMDEV */ 22 # if !TLS_NO_RSA 23 static RSA *rsa_tmp = NULL; /* temporary RSA key */ 24 static RSA *tmp_rsa_key __P((SSL *, int, int)); 25 # endif /* !TLS_NO_RSA */ 26 # if !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER < 0x00907000L 27 static int tls_verify_cb __P((X509_STORE_CTX *)); 28 # else /* !defined() || OPENSSL_VERSION_NUMBER < 0x00907000L */ 29 static int tls_verify_cb __P((X509_STORE_CTX *, void *)); 30 # endif /* !defined() || OPENSSL_VERSION_NUMBER < 0x00907000L */ 31 32 # if OPENSSL_VERSION_NUMBER > 0x00907000L 33 static int x509_verify_cb __P((int, X509_STORE_CTX *)); 34 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */ 35 36 # if !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER < 0x00907000L 37 # define CONST097 38 # else /* !defined() || OPENSSL_VERSION_NUMBER < 0x00907000L */ 39 # define CONST097 const 40 # endif /* !defined() || OPENSSL_VERSION_NUMBER < 0x00907000L */ 41 static void apps_ssl_info_cb __P((CONST097 SSL *, int , int)); 42 static bool tls_ok_f __P((char *, char *, int)); 43 static bool tls_safe_f __P((char *, long, bool)); 44 static int tls_verify_log __P((int, X509_STORE_CTX *, char *)); 45 46 # if !NO_DH 47 static DH *get_dh512 __P((void)); 48 49 static unsigned char dh512_p[] = 50 { 51 0xDA,0x58,0x3C,0x16,0xD9,0x85,0x22,0x89,0xD0,0xE4,0xAF,0x75, 52 0x6F,0x4C,0xCA,0x92,0xDD,0x4B,0xE5,0x33,0xB8,0x04,0xFB,0x0F, 53 0xED,0x94,0xEF,0x9C,0x8A,0x44,0x03,0xED,0x57,0x46,0x50,0xD3, 54 0x69,0x99,0xDB,0x29,0xD7,0x76,0x27,0x6B,0xA2,0xD3,0xD4,0x12, 55 0xE2,0x18,0xF4,0xDD,0x1E,0x08,0x4C,0xF6,0xD8,0x00,0x3E,0x7C, 56 0x47,0x74,0xE8,0x33 57 }; 58 static unsigned char dh512_g[] = 59 { 60 0x02 61 }; 62 63 static DH * 64 get_dh512() 65 { 66 DH *dh = NULL; 67 68 if ((dh = DH_new()) == NULL) 69 return NULL; 70 dh->p = BN_bin2bn(dh512_p, sizeof(dh512_p), NULL); 71 dh->g = BN_bin2bn(dh512_g, sizeof(dh512_g), NULL); 72 if ((dh->p == NULL) || (dh->g == NULL)) 73 return NULL; 74 return dh; 75 } 76 # endif /* !NO_DH */ 77 78 79 /* 80 ** TLS_RAND_INIT -- initialize STARTTLS random generator 81 ** 82 ** Parameters: 83 ** randfile -- name of file with random data 84 ** logl -- loglevel 85 ** 86 ** Returns: 87 ** success/failure 88 ** 89 ** Side Effects: 90 ** initializes PRNG for tls library. 91 */ 92 93 # define MIN_RAND_BYTES 128 /* 1024 bits */ 94 95 # define RF_OK 0 /* randfile OK */ 96 # define RF_MISS 1 /* randfile == NULL || *randfile == '\0' */ 97 # define RF_UNKNOWN 2 /* unknown prefix for randfile */ 98 99 # define RI_NONE 0 /* no init yet */ 100 # define RI_SUCCESS 1 /* init was successful */ 101 # define RI_FAIL 2 /* init failed */ 102 103 static bool tls_rand_init __P((char *, int)); 104 105 static bool 106 tls_rand_init(randfile, logl) 107 char *randfile; 108 int logl; 109 { 110 # ifndef HASURANDOMDEV 111 /* not required if /dev/urandom exists, OpenSSL does it internally */ 112 113 bool ok; 114 int randdef; 115 static int done = RI_NONE; 116 117 /* 118 ** initialize PRNG 119 */ 120 121 /* did we try this before? if yes: return old value */ 122 if (done != RI_NONE) 123 return done == RI_SUCCESS; 124 125 /* set default values */ 126 ok = false; 127 done = RI_FAIL; 128 randdef = (randfile == NULL || *randfile == '\0') ? RF_MISS : RF_OK; 129 # if EGD 130 if (randdef == RF_OK && sm_strncasecmp(randfile, "egd:", 4) == 0) 131 { 132 randfile += 4; 133 if (RAND_egd(randfile) < 0) 134 { 135 sm_syslog(LOG_WARNING, NOQID, 136 "STARTTLS: RAND_egd(%s) failed: random number generator not seeded", 137 randfile); 138 } 139 else 140 ok = true; 141 } 142 else 143 # endif /* EGD */ 144 if (randdef == RF_OK && sm_strncasecmp(randfile, "file:", 5) == 0) 145 { 146 int fd; 147 long sff; 148 struct stat st; 149 150 randfile += 5; 151 sff = SFF_SAFEDIRPATH | SFF_NOWLINK 152 | SFF_NOGWFILES | SFF_NOWWFILES 153 | SFF_NOGRFILES | SFF_NOWRFILES 154 | SFF_MUSTOWN | SFF_ROOTOK | SFF_OPENASROOT; 155 if (DontLockReadFiles) 156 sff |= SFF_NOLOCK; 157 if ((fd = safeopen(randfile, O_RDONLY, 0, sff)) >= 0) 158 { 159 if (fstat(fd, &st) < 0) 160 { 161 if (LogLevel > logl) 162 sm_syslog(LOG_ERR, NOQID, 163 "STARTTLS: can't fstat(%s)", 164 randfile); 165 } 166 else 167 { 168 bool use, problem; 169 170 use = true; 171 problem = false; 172 173 /* max. age of file: 10 minutes */ 174 if (st.st_mtime + 600 < curtime()) 175 { 176 use = bitnset(DBS_INSUFFICIENTENTROPY, 177 DontBlameSendmail); 178 problem = true; 179 if (LogLevel > logl) 180 sm_syslog(LOG_ERR, NOQID, 181 "STARTTLS: RandFile %s too old: %s", 182 randfile, 183 use ? "unsafe" : 184 "unusable"); 185 } 186 if (use && st.st_size < MIN_RAND_BYTES) 187 { 188 use = bitnset(DBS_INSUFFICIENTENTROPY, 189 DontBlameSendmail); 190 problem = true; 191 if (LogLevel > logl) 192 sm_syslog(LOG_ERR, NOQID, 193 "STARTTLS: size(%s) < %d: %s", 194 randfile, 195 MIN_RAND_BYTES, 196 use ? "unsafe" : 197 "unusable"); 198 } 199 if (use) 200 ok = RAND_load_file(randfile, -1) >= 201 MIN_RAND_BYTES; 202 if (use && !ok) 203 { 204 if (LogLevel > logl) 205 sm_syslog(LOG_WARNING, NOQID, 206 "STARTTLS: RAND_load_file(%s) failed: random number generator not seeded", 207 randfile); 208 } 209 if (problem) 210 ok = false; 211 } 212 if (ok || bitnset(DBS_INSUFFICIENTENTROPY, 213 DontBlameSendmail)) 214 { 215 /* add this even if fstat() failed */ 216 RAND_seed((void *) &st, sizeof st); 217 } 218 (void) close(fd); 219 } 220 else 221 { 222 if (LogLevel > logl) 223 sm_syslog(LOG_WARNING, NOQID, 224 "STARTTLS: Warning: safeopen(%s) failed", 225 randfile); 226 } 227 } 228 else if (randdef == RF_OK) 229 { 230 if (LogLevel > logl) 231 sm_syslog(LOG_WARNING, NOQID, 232 "STARTTLS: Error: no proper random file definition %s", 233 randfile); 234 randdef = RF_UNKNOWN; 235 } 236 if (randdef == RF_MISS) 237 { 238 if (LogLevel > logl) 239 sm_syslog(LOG_WARNING, NOQID, 240 "STARTTLS: Error: missing random file definition"); 241 } 242 if (!ok && bitnset(DBS_INSUFFICIENTENTROPY, DontBlameSendmail)) 243 { 244 int i; 245 long r; 246 unsigned char buf[MIN_RAND_BYTES]; 247 248 /* assert((MIN_RAND_BYTES % sizeof(long)) == 0); */ 249 for (i = 0; i <= sizeof(buf) - sizeof(long); i += sizeof(long)) 250 { 251 r = get_random(); 252 (void) memcpy(buf + i, (void *) &r, sizeof(long)); 253 } 254 RAND_seed(buf, sizeof buf); 255 if (LogLevel > logl) 256 sm_syslog(LOG_WARNING, NOQID, 257 "STARTTLS: Warning: random number generator not properly seeded"); 258 ok = true; 259 } 260 done = ok ? RI_SUCCESS : RI_FAIL; 261 return ok; 262 # else /* ! HASURANDOMDEV */ 263 return true; 264 # endif /* ! HASURANDOMDEV */ 265 } 266 /* 267 ** INIT_TLS_LIBRARY -- Calls functions which setup TLS library for global use. 268 ** 269 ** Parameters: 270 ** none. 271 ** 272 ** Returns: 273 ** succeeded? 274 */ 275 276 bool 277 init_tls_library() 278 { 279 /* basic TLS initialization, ignore result for now */ 280 SSL_library_init(); 281 SSL_load_error_strings(); 282 # if 0 283 /* this is currently a macro for SSL_library_init */ 284 SSLeay_add_ssl_algorithms(); 285 # endif /* 0 */ 286 287 return tls_rand_init(RandFile, 7); 288 } 289 /* 290 ** TLS_SET_VERIFY -- request client certificate? 291 ** 292 ** Parameters: 293 ** ctx -- TLS context 294 ** ssl -- TLS structure 295 ** vrfy -- require certificate? 296 ** 297 ** Returns: 298 ** none. 299 ** 300 ** Side Effects: 301 ** Sets verification state for TLS 302 ** 303 # if TLS_VRFY_PER_CTX 304 ** Notice: 305 ** This is per TLS context, not per TLS structure; 306 ** the former is global, the latter per connection. 307 ** It would be nice to do this per connection, but this 308 ** doesn't work in the current TLS libraries :-( 309 # endif * TLS_VRFY_PER_CTX * 310 */ 311 312 void 313 tls_set_verify(ctx, ssl, vrfy) 314 SSL_CTX *ctx; 315 SSL *ssl; 316 bool vrfy; 317 { 318 # if !TLS_VRFY_PER_CTX 319 SSL_set_verify(ssl, vrfy ? SSL_VERIFY_PEER : SSL_VERIFY_NONE, NULL); 320 # else /* !TLS_VRFY_PER_CTX */ 321 SSL_CTX_set_verify(ctx, vrfy ? SSL_VERIFY_PEER : SSL_VERIFY_NONE, 322 NULL); 323 # endif /* !TLS_VRFY_PER_CTX */ 324 } 325 326 /* 327 ** status in initialization 328 ** these flags keep track of the status of the initialization 329 ** i.e., whether a file exists (_EX) and whether it can be used (_OK) 330 ** [due to permissions] 331 */ 332 333 # define TLS_S_NONE 0x00000000 /* none yet */ 334 # define TLS_S_CERT_EX 0x00000001 /* cert file exists */ 335 # define TLS_S_CERT_OK 0x00000002 /* cert file is ok */ 336 # define TLS_S_KEY_EX 0x00000004 /* key file exists */ 337 # define TLS_S_KEY_OK 0x00000008 /* key file is ok */ 338 # define TLS_S_CERTP_EX 0x00000010 /* CA cert path exists */ 339 # define TLS_S_CERTP_OK 0x00000020 /* CA cert path is ok */ 340 # define TLS_S_CERTF_EX 0x00000040 /* CA cert file exists */ 341 # define TLS_S_CERTF_OK 0x00000080 /* CA cert file is ok */ 342 # define TLS_S_CRLF_EX 0x00000100 /* CRL file exists */ 343 # define TLS_S_CRLF_OK 0x00000200 /* CRL file is ok */ 344 345 # if _FFR_TLS_1 346 # define TLS_S_CERT2_EX 0x00001000 /* 2nd cert file exists */ 347 # define TLS_S_CERT2_OK 0x00002000 /* 2nd cert file is ok */ 348 # define TLS_S_KEY2_EX 0x00004000 /* 2nd key file exists */ 349 # define TLS_S_KEY2_OK 0x00008000 /* 2nd key file is ok */ 350 # endif /* _FFR_TLS_1 */ 351 352 # define TLS_S_DH_OK 0x00200000 /* DH cert is ok */ 353 # define TLS_S_DHPAR_EX 0x00400000 /* DH param file exists */ 354 # define TLS_S_DHPAR_OK 0x00800000 /* DH param file is ok to use */ 355 356 /* Type of variable */ 357 # define TLS_T_OTHER 0 358 # define TLS_T_SRV 1 359 # define TLS_T_CLT 2 360 361 /* 362 ** TLS_OK_F -- can var be an absolute filename? 363 ** 364 ** Parameters: 365 ** var -- filename 366 ** fn -- what is the filename used for? 367 ** type -- type of variable 368 ** 369 ** Returns: 370 ** ok? 371 */ 372 373 static bool 374 tls_ok_f(var, fn, type) 375 char *var; 376 char *fn; 377 int type; 378 { 379 /* must be absolute pathname */ 380 if (var != NULL && *var == '/') 381 return true; 382 if (LogLevel > 12) 383 sm_syslog(LOG_WARNING, NOQID, "STARTTLS: %s%s missing", 384 type == TLS_T_SRV ? "Server" : 385 (type == TLS_T_CLT ? "Client" : ""), fn); 386 return false; 387 } 388 /* 389 ** TLS_SAFE_F -- is a file safe to use? 390 ** 391 ** Parameters: 392 ** var -- filename 393 ** sff -- flags for safefile() 394 ** srv -- server side? 395 ** 396 ** Returns: 397 ** ok? 398 */ 399 400 static bool 401 tls_safe_f(var, sff, srv) 402 char *var; 403 long sff; 404 bool srv; 405 { 406 int ret; 407 408 if ((ret = safefile(var, RunAsUid, RunAsGid, RunAsUserName, sff, 409 S_IRUSR, NULL)) == 0) 410 return true; 411 if (LogLevel > 7) 412 sm_syslog(LOG_WARNING, NOQID, "STARTTLS=%s: file %s unsafe: %s", 413 srv ? "server" : "client", var, sm_errstring(ret)); 414 return false; 415 } 416 417 /* 418 ** TLS_OK_F -- macro to simplify calls to tls_ok_f 419 ** 420 ** Parameters: 421 ** var -- filename 422 ** fn -- what is the filename used for? 423 ** req -- is the file required? 424 ** st -- status bit to set if ok 425 ** type -- type of variable 426 ** 427 ** Side Effects: 428 ** uses r, ok; may change ok and status. 429 ** 430 */ 431 432 # define TLS_OK_F(var, fn, req, st, type) if (ok) \ 433 { \ 434 r = tls_ok_f(var, fn, type); \ 435 if (r) \ 436 status |= st; \ 437 else if (req) \ 438 ok = false; \ 439 } 440 441 /* 442 ** TLS_UNR -- macro to return whether a file should be unreadable 443 ** 444 ** Parameters: 445 ** bit -- flag to test 446 ** req -- flags 447 ** 448 ** Returns: 449 ** 0/SFF_NORFILES 450 */ 451 # define TLS_UNR(bit, req) (bitset(bit, req) ? SFF_NORFILES : 0) 452 # define TLS_OUNR(bit, req) (bitset(bit, req) ? SFF_NOWRFILES : 0) 453 # define TLS_KEYSFF(req) \ 454 (bitnset(DBS_GROUPREADABLEKEYFILE, DontBlameSendmail) ? \ 455 TLS_OUNR(TLS_I_KEY_OUNR, req) : \ 456 TLS_UNR(TLS_I_KEY_UNR, req)) 457 458 /* 459 ** TLS_SAFE_F -- macro to simplify calls to tls_safe_f 460 ** 461 ** Parameters: 462 ** var -- filename 463 ** sff -- flags for safefile() 464 ** req -- is the file required? 465 ** ex -- does the file exist? 466 ** st -- status bit to set if ok 467 ** srv -- server side? 468 ** 469 ** Side Effects: 470 ** uses r, ok, ex; may change ok and status. 471 ** 472 */ 473 474 # define TLS_SAFE_F(var, sff, req, ex, st, srv) if (ex && ok) \ 475 { \ 476 r = tls_safe_f(var, sff, srv); \ 477 if (r) \ 478 status |= st; \ 479 else if (req) \ 480 ok = false; \ 481 } 482 483 /* 484 ** INITTLS -- initialize TLS 485 ** 486 ** Parameters: 487 ** ctx -- pointer to context 488 ** req -- requirements for initialization (see sendmail.h) 489 ** srv -- server side? 490 ** certfile -- filename of certificate 491 ** keyfile -- filename of private key 492 ** cacertpath -- path to CAs 493 ** cacertfile -- file with CA(s) 494 ** dhparam -- parameters for DH 495 ** 496 ** Returns: 497 ** succeeded? 498 */ 499 500 /* 501 ** The session_id_context identifies the service that created a session. 502 ** This information is used to distinguish between multiple TLS-based 503 ** servers running on the same server. We use the name of the mail system. 504 ** Note: the session cache is not persistent. 505 */ 506 507 static char server_session_id_context[] = "sendmail8"; 508 509 bool 510 inittls(ctx, req, srv, certfile, keyfile, cacertpath, cacertfile, dhparam) 511 SSL_CTX **ctx; 512 unsigned long req; 513 bool srv; 514 char *certfile, *keyfile, *cacertpath, *cacertfile, *dhparam; 515 { 516 # if !NO_DH 517 static DH *dh = NULL; 518 # endif /* !NO_DH */ 519 int r; 520 bool ok; 521 long sff, status; 522 char *who; 523 # if _FFR_TLS_1 524 char *cf2, *kf2; 525 # endif /* _FFR_TLS_1 */ 526 # if SM_CONF_SHM 527 extern int ShmId; 528 # endif /* SM_CONF_SHM */ 529 # if OPENSSL_VERSION_NUMBER > 0x00907000L 530 BIO *crl_file; 531 X509_CRL *crl; 532 X509_STORE *store; 533 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */ 534 535 status = TLS_S_NONE; 536 who = srv ? "server" : "client"; 537 if (ctx == NULL) 538 syserr("STARTTLS=%s, inittls: ctx == NULL", who); 539 540 /* already initialized? (we could re-init...) */ 541 if (*ctx != NULL) 542 return true; 543 ok = true; 544 545 # if _FFR_TLS_1 546 /* 547 ** look for a second filename: it must be separated by a ',' 548 ** no blanks allowed (they won't be skipped). 549 ** we change a global variable here! this change will be undone 550 ** before return from the function but only if it returns true. 551 ** this isn't a problem since in a failure case this function 552 ** won't be called again with the same (overwritten) values. 553 ** otherwise each return must be replaced with a goto endinittls. 554 */ 555 556 cf2 = NULL; 557 kf2 = NULL; 558 if (certfile != NULL && (cf2 = strchr(certfile, ',')) != NULL) 559 { 560 *cf2++ = '\0'; 561 if (keyfile != NULL && (kf2 = strchr(keyfile, ',')) != NULL) 562 *kf2++ = '\0'; 563 } 564 # endif /* _FFR_TLS_1 */ 565 566 /* 567 ** Check whether files/paths are defined 568 */ 569 570 TLS_OK_F(certfile, "CertFile", bitset(TLS_I_CERT_EX, req), 571 TLS_S_CERT_EX, srv ? TLS_T_SRV : TLS_T_CLT); 572 TLS_OK_F(keyfile, "KeyFile", bitset(TLS_I_KEY_EX, req), 573 TLS_S_KEY_EX, srv ? TLS_T_SRV : TLS_T_CLT); 574 TLS_OK_F(cacertpath, "CACertPath", bitset(TLS_I_CERTP_EX, req), 575 TLS_S_CERTP_EX, TLS_T_OTHER); 576 TLS_OK_F(cacertfile, "CACertFile", bitset(TLS_I_CERTF_EX, req), 577 TLS_S_CERTF_EX, TLS_T_OTHER); 578 579 # if OPENSSL_VERSION_NUMBER > 0x00907000L 580 TLS_OK_F(CRLFile, "CRLFile", bitset(TLS_I_CRLF_EX, req), 581 TLS_S_CRLF_EX, TLS_T_OTHER); 582 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */ 583 584 # if _FFR_TLS_1 585 /* 586 ** if the second file is specified it must exist 587 ** XXX: it is possible here to define only one of those files 588 */ 589 590 if (cf2 != NULL) 591 { 592 TLS_OK_F(cf2, "CertFile", bitset(TLS_I_CERT_EX, req), 593 TLS_S_CERT2_EX, srv ? TLS_T_SRV : TLS_T_CLT); 594 } 595 if (kf2 != NULL) 596 { 597 TLS_OK_F(kf2, "KeyFile", bitset(TLS_I_KEY_EX, req), 598 TLS_S_KEY2_EX, srv ? TLS_T_SRV : TLS_T_CLT); 599 } 600 # endif /* _FFR_TLS_1 */ 601 602 /* 603 ** valid values for dhparam are (only the first char is checked) 604 ** none no parameters: don't use DH 605 ** 512 generate 512 bit parameters (fixed) 606 ** 1024 generate 1024 bit parameters 607 ** /file/name read parameters from /file/name 608 ** default is: 1024 for server, 512 for client (OK? XXX) 609 */ 610 611 if (bitset(TLS_I_TRY_DH, req)) 612 { 613 if (dhparam != NULL) 614 { 615 char c = *dhparam; 616 617 if (c == '1') 618 req |= TLS_I_DH1024; 619 else if (c == '5') 620 req |= TLS_I_DH512; 621 else if (c != 'n' && c != 'N' && c != '/') 622 { 623 if (LogLevel > 12) 624 sm_syslog(LOG_WARNING, NOQID, 625 "STARTTLS=%s, error: illegal value '%s' for DHParam", 626 who, dhparam); 627 dhparam = NULL; 628 } 629 } 630 if (dhparam == NULL) 631 dhparam = srv ? "1" : "5"; 632 else if (*dhparam == '/') 633 { 634 TLS_OK_F(dhparam, "DHParameters", 635 bitset(TLS_I_DHPAR_EX, req), 636 TLS_S_DHPAR_EX, TLS_T_OTHER); 637 } 638 } 639 if (!ok) 640 return ok; 641 642 /* certfile etc. must be "safe". */ 643 sff = SFF_REGONLY | SFF_SAFEDIRPATH | SFF_NOWLINK 644 | SFF_NOGWFILES | SFF_NOWWFILES 645 | SFF_MUSTOWN | SFF_ROOTOK | SFF_OPENASROOT; 646 if (DontLockReadFiles) 647 sff |= SFF_NOLOCK; 648 649 TLS_SAFE_F(certfile, sff | TLS_UNR(TLS_I_CERT_UNR, req), 650 bitset(TLS_I_CERT_EX, req), 651 bitset(TLS_S_CERT_EX, status), TLS_S_CERT_OK, srv); 652 TLS_SAFE_F(keyfile, sff | TLS_KEYSFF(req), 653 bitset(TLS_I_KEY_EX, req), 654 bitset(TLS_S_KEY_EX, status), TLS_S_KEY_OK, srv); 655 TLS_SAFE_F(cacertfile, sff | TLS_UNR(TLS_I_CERTF_UNR, req), 656 bitset(TLS_I_CERTF_EX, req), 657 bitset(TLS_S_CERTF_EX, status), TLS_S_CERTF_OK, srv); 658 TLS_SAFE_F(dhparam, sff | TLS_UNR(TLS_I_DHPAR_UNR, req), 659 bitset(TLS_I_DHPAR_EX, req), 660 bitset(TLS_S_DHPAR_EX, status), TLS_S_DHPAR_OK, srv); 661 # if OPENSSL_VERSION_NUMBER > 0x00907000L 662 TLS_SAFE_F(CRLFile, sff | TLS_UNR(TLS_I_CRLF_UNR, req), 663 bitset(TLS_I_CRLF_EX, req), 664 bitset(TLS_S_CRLF_EX, status), TLS_S_CRLF_OK, srv); 665 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */ 666 if (!ok) 667 return ok; 668 # if _FFR_TLS_1 669 if (cf2 != NULL) 670 { 671 TLS_SAFE_F(cf2, sff | TLS_UNR(TLS_I_CERT_UNR, req), 672 bitset(TLS_I_CERT_EX, req), 673 bitset(TLS_S_CERT2_EX, status), TLS_S_CERT2_OK, srv); 674 } 675 if (kf2 != NULL) 676 { 677 TLS_SAFE_F(kf2, sff | TLS_KEYSFF(req), 678 bitset(TLS_I_KEY_EX, req), 679 bitset(TLS_S_KEY2_EX, status), TLS_S_KEY2_OK, srv); 680 } 681 # endif /* _FFR_TLS_1 */ 682 683 /* create a method and a new context */ 684 if ((*ctx = SSL_CTX_new(srv ? SSLv23_server_method() : 685 SSLv23_client_method())) == NULL) 686 { 687 if (LogLevel > 7) 688 sm_syslog(LOG_WARNING, NOQID, 689 "STARTTLS=%s, error: SSL_CTX_new(SSLv23_%s_method()) failed", 690 who, who); 691 if (LogLevel > 9) 692 tlslogerr(who); 693 return false; 694 } 695 696 # if OPENSSL_VERSION_NUMBER > 0x00907000L 697 if (CRLFile != NULL) 698 { 699 /* get a pointer to the current certificate validation store */ 700 store = SSL_CTX_get_cert_store(*ctx); /* does not fail */ 701 crl_file = BIO_new(BIO_s_file_internal()); 702 if (crl_file != NULL) 703 { 704 if (BIO_read_filename(crl_file, CRLFile) >= 0) 705 { 706 crl = PEM_read_bio_X509_CRL(crl_file, NULL, 707 NULL, NULL); 708 BIO_free(crl_file); 709 X509_STORE_add_crl(store, crl); 710 X509_CRL_free(crl); 711 X509_STORE_set_flags(store, 712 X509_V_FLAG_CRL_CHECK|X509_V_FLAG_CRL_CHECK_ALL); 713 X509_STORE_set_verify_cb_func(store, 714 x509_verify_cb); 715 } 716 else 717 { 718 if (LogLevel > 9) 719 { 720 sm_syslog(LOG_WARNING, NOQID, 721 "STARTTLS=%s, error: PEM_read_bio_X509_CRL(%s)=failed", 722 who, CRLFile); 723 } 724 725 /* avoid memory leaks */ 726 BIO_free(crl_file); 727 return false; 728 } 729 730 } 731 else if (LogLevel > 9) 732 sm_syslog(LOG_WARNING, NOQID, 733 "STARTTLS=%s, error: BIO_new=failed", who); 734 } 735 # if _FFR_CRLPATH 736 if (CRLPath != NULL) 737 { 738 X509_LOOKUP *lookup; 739 740 lookup = X509_STORE_add_lookup(store, X509_LOOKUP_hash_dir()); 741 if (lookup == NULL) 742 { 743 if (LogLevel > 9) 744 { 745 sm_syslog(LOG_WARNING, NOQID, 746 "STARTTLS=%s, error: X509_STORE_add_lookup(hash)=failed", 747 who, CRLFile); 748 } 749 return false; 750 } 751 X509_LOOKUP_add_dir(lookup, CRLPath, X509_FILETYPE_PEM); 752 X509_STORE_set_flags(store, 753 X509_V_FLAG_CRL_CHECK|X509_V_FLAG_CRL_CHECK_ALL); 754 } 755 # endif /* _FFR_CRLPATH */ 756 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */ 757 758 # if TLS_NO_RSA 759 /* turn off backward compatibility, required for no-rsa */ 760 SSL_CTX_set_options(*ctx, SSL_OP_NO_SSLv2); 761 # endif /* TLS_NO_RSA */ 762 763 764 # if !TLS_NO_RSA 765 /* 766 ** Create a temporary RSA key 767 ** XXX Maybe we shouldn't create this always (even though it 768 ** is only at startup). 769 ** It is a time-consuming operation and it is not always necessary. 770 ** maybe we should do it only on demand... 771 */ 772 773 if (bitset(TLS_I_RSA_TMP, req) 774 # if SM_CONF_SHM 775 && ShmId != SM_SHM_NO_ID && 776 (rsa_tmp = RSA_generate_key(RSA_KEYLENGTH, RSA_F4, NULL, 777 NULL)) == NULL 778 # else /* SM_CONF_SHM */ 779 && 0 /* no shared memory: no need to generate key now */ 780 # endif /* SM_CONF_SHM */ 781 ) 782 { 783 if (LogLevel > 7) 784 { 785 sm_syslog(LOG_WARNING, NOQID, 786 "STARTTLS=%s, error: RSA_generate_key failed", 787 who); 788 if (LogLevel > 9) 789 tlslogerr(who); 790 } 791 return false; 792 } 793 # endif /* !TLS_NO_RSA */ 794 795 /* 796 ** load private key 797 ** XXX change this for DSA-only version 798 */ 799 800 if (bitset(TLS_S_KEY_OK, status) && 801 SSL_CTX_use_PrivateKey_file(*ctx, keyfile, 802 SSL_FILETYPE_PEM) <= 0) 803 { 804 if (LogLevel > 7) 805 { 806 sm_syslog(LOG_WARNING, NOQID, 807 "STARTTLS=%s, error: SSL_CTX_use_PrivateKey_file(%s) failed", 808 who, keyfile); 809 if (LogLevel > 9) 810 tlslogerr(who); 811 } 812 if (bitset(TLS_I_USE_KEY, req)) 813 return false; 814 } 815 816 /* get the certificate file */ 817 if (bitset(TLS_S_CERT_OK, status) && 818 SSL_CTX_use_certificate_file(*ctx, certfile, 819 SSL_FILETYPE_PEM) <= 0) 820 { 821 if (LogLevel > 7) 822 { 823 sm_syslog(LOG_WARNING, NOQID, 824 "STARTTLS=%s, error: SSL_CTX_use_certificate_file(%s) failed", 825 who, certfile); 826 if (LogLevel > 9) 827 tlslogerr(who); 828 } 829 if (bitset(TLS_I_USE_CERT, req)) 830 return false; 831 } 832 833 /* check the private key */ 834 if (bitset(TLS_S_KEY_OK, status) && 835 (r = SSL_CTX_check_private_key(*ctx)) <= 0) 836 { 837 /* Private key does not match the certificate public key */ 838 if (LogLevel > 5) 839 { 840 sm_syslog(LOG_WARNING, NOQID, 841 "STARTTLS=%s, error: SSL_CTX_check_private_key failed(%s): %d", 842 who, keyfile, r); 843 if (LogLevel > 9) 844 tlslogerr(who); 845 } 846 if (bitset(TLS_I_USE_KEY, req)) 847 return false; 848 } 849 850 # if _FFR_TLS_1 851 /* XXX this code is pretty much duplicated from above! */ 852 853 /* load private key */ 854 if (bitset(TLS_S_KEY2_OK, status) && 855 SSL_CTX_use_PrivateKey_file(*ctx, kf2, SSL_FILETYPE_PEM) <= 0) 856 { 857 if (LogLevel > 7) 858 { 859 sm_syslog(LOG_WARNING, NOQID, 860 "STARTTLS=%s, error: SSL_CTX_use_PrivateKey_file(%s) failed", 861 who, kf2); 862 if (LogLevel > 9) 863 tlslogerr(who); 864 } 865 } 866 867 /* get the certificate file */ 868 if (bitset(TLS_S_CERT2_OK, status) && 869 SSL_CTX_use_certificate_file(*ctx, cf2, SSL_FILETYPE_PEM) <= 0) 870 { 871 if (LogLevel > 7) 872 { 873 sm_syslog(LOG_WARNING, NOQID, 874 "STARTTLS=%s, error: SSL_CTX_use_certificate_file(%s) failed", 875 who, cf2); 876 if (LogLevel > 9) 877 tlslogerr(who); 878 } 879 } 880 881 /* also check the private key */ 882 if (bitset(TLS_S_KEY2_OK, status) && 883 (r = SSL_CTX_check_private_key(*ctx)) <= 0) 884 { 885 /* Private key does not match the certificate public key */ 886 if (LogLevel > 5) 887 { 888 sm_syslog(LOG_WARNING, NOQID, 889 "STARTTLS=%s, error: SSL_CTX_check_private_key 2 failed: %d", 890 who, r); 891 if (LogLevel > 9) 892 tlslogerr(who); 893 } 894 } 895 # endif /* _FFR_TLS_1 */ 896 897 /* SSL_CTX_set_quiet_shutdown(*ctx, 1); violation of standard? */ 898 SSL_CTX_set_options(*ctx, SSL_OP_ALL); /* XXX bug compatibility? */ 899 900 # if !NO_DH 901 /* Diffie-Hellman initialization */ 902 if (bitset(TLS_I_TRY_DH, req)) 903 { 904 if (bitset(TLS_S_DHPAR_OK, status)) 905 { 906 BIO *bio; 907 908 if ((bio = BIO_new_file(dhparam, "r")) != NULL) 909 { 910 dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL); 911 BIO_free(bio); 912 if (dh == NULL && LogLevel > 7) 913 { 914 unsigned long err; 915 916 err = ERR_get_error(); 917 sm_syslog(LOG_WARNING, NOQID, 918 "STARTTLS=%s, error: cannot read DH parameters(%s): %s", 919 who, dhparam, 920 ERR_error_string(err, NULL)); 921 if (LogLevel > 9) 922 tlslogerr(who); 923 } 924 } 925 else 926 { 927 if (LogLevel > 5) 928 { 929 sm_syslog(LOG_WARNING, NOQID, 930 "STARTTLS=%s, error: BIO_new_file(%s) failed", 931 who, dhparam); 932 if (LogLevel > 9) 933 tlslogerr(who); 934 } 935 } 936 } 937 if (dh == NULL && bitset(TLS_I_DH1024, req)) 938 { 939 DSA *dsa; 940 941 /* this takes a while! (7-130s on a 450MHz AMD K6-2) */ 942 dsa = DSA_generate_parameters(1024, NULL, 0, NULL, 943 NULL, 0, NULL); 944 dh = DSA_dup_DH(dsa); 945 DSA_free(dsa); 946 } 947 else 948 if (dh == NULL && bitset(TLS_I_DH512, req)) 949 dh = get_dh512(); 950 951 if (dh == NULL) 952 { 953 if (LogLevel > 9) 954 { 955 unsigned long err; 956 957 err = ERR_get_error(); 958 sm_syslog(LOG_WARNING, NOQID, 959 "STARTTLS=%s, error: cannot read or set DH parameters(%s): %s", 960 who, dhparam, 961 ERR_error_string(err, NULL)); 962 } 963 if (bitset(TLS_I_REQ_DH, req)) 964 return false; 965 } 966 else 967 { 968 SSL_CTX_set_tmp_dh(*ctx, dh); 969 970 /* important to avoid small subgroup attacks */ 971 SSL_CTX_set_options(*ctx, SSL_OP_SINGLE_DH_USE); 972 if (LogLevel > 13) 973 sm_syslog(LOG_INFO, NOQID, 974 "STARTTLS=%s, Diffie-Hellman init, key=%d bit (%c)", 975 who, 8 * DH_size(dh), *dhparam); 976 DH_free(dh); 977 } 978 } 979 # endif /* !NO_DH */ 980 981 982 /* XXX do we need this cache here? */ 983 if (bitset(TLS_I_CACHE, req)) 984 { 985 SSL_CTX_sess_set_cache_size(*ctx, 1); 986 SSL_CTX_set_timeout(*ctx, 1); 987 SSL_CTX_set_session_id_context(*ctx, 988 (void *) &server_session_id_context, 989 sizeof(server_session_id_context)); 990 (void) SSL_CTX_set_session_cache_mode(*ctx, 991 SSL_SESS_CACHE_SERVER); 992 } 993 else 994 { 995 (void) SSL_CTX_set_session_cache_mode(*ctx, 996 SSL_SESS_CACHE_OFF); 997 } 998 999 /* load certificate locations and default CA paths */ 1000 if (bitset(TLS_S_CERTP_EX, status) && bitset(TLS_S_CERTF_EX, status)) 1001 { 1002 if ((r = SSL_CTX_load_verify_locations(*ctx, cacertfile, 1003 cacertpath)) == 1) 1004 { 1005 # if !TLS_NO_RSA 1006 if (bitset(TLS_I_RSA_TMP, req)) 1007 SSL_CTX_set_tmp_rsa_callback(*ctx, tmp_rsa_key); 1008 # endif /* !TLS_NO_RSA */ 1009 1010 /* 1011 ** We have to install our own verify callback: 1012 ** SSL_VERIFY_PEER requests a client cert but even 1013 ** though *FAIL_IF* isn't set, the connection 1014 ** will be aborted if the client presents a cert 1015 ** that is not "liked" (can't be verified?) by 1016 ** the TLS library :-( 1017 */ 1018 1019 /* 1020 ** XXX currently we could call tls_set_verify() 1021 ** but we hope that that function will later on 1022 ** only set the mode per connection. 1023 */ 1024 SSL_CTX_set_verify(*ctx, 1025 bitset(TLS_I_NO_VRFY, req) ? SSL_VERIFY_NONE 1026 : SSL_VERIFY_PEER, 1027 NULL); 1028 1029 /* install verify callback */ 1030 SSL_CTX_set_cert_verify_callback(*ctx, tls_verify_cb, 1031 NULL); 1032 SSL_CTX_set_client_CA_list(*ctx, 1033 SSL_load_client_CA_file(cacertfile)); 1034 } 1035 else 1036 { 1037 /* 1038 ** can't load CA data; do we care? 1039 ** the data is necessary to authenticate the client, 1040 ** which in turn would be necessary 1041 ** if we want to allow relaying based on it. 1042 */ 1043 if (LogLevel > 5) 1044 { 1045 sm_syslog(LOG_WARNING, NOQID, 1046 "STARTTLS=%s, error: load verify locs %s, %s failed: %d", 1047 who, cacertpath, cacertfile, r); 1048 if (LogLevel > 9) 1049 tlslogerr(who); 1050 } 1051 if (bitset(TLS_I_VRFY_LOC, req)) 1052 return false; 1053 } 1054 } 1055 1056 /* XXX: make this dependent on an option? */ 1057 if (tTd(96, 9)) 1058 SSL_CTX_set_info_callback(*ctx, apps_ssl_info_cb); 1059 1060 # if _FFR_TLS_1 1061 /* install our own cipher list */ 1062 if (CipherList != NULL && *CipherList != '\0') 1063 { 1064 if (SSL_CTX_set_cipher_list(*ctx, CipherList) <= 0) 1065 { 1066 if (LogLevel > 7) 1067 { 1068 sm_syslog(LOG_WARNING, NOQID, 1069 "STARTTLS=%s, error: SSL_CTX_set_cipher_list(%s) failed, list ignored", 1070 who, CipherList); 1071 1072 if (LogLevel > 9) 1073 tlslogerr(who); 1074 } 1075 /* failure if setting to this list is required? */ 1076 } 1077 } 1078 # endif /* _FFR_TLS_1 */ 1079 if (LogLevel > 12) 1080 sm_syslog(LOG_INFO, NOQID, "STARTTLS=%s, init=%d", who, ok); 1081 1082 # if _FFR_TLS_1 1083 # if 0 1084 /* 1085 ** this label is required if we want to have a "clean" exit 1086 ** see the comments above at the initialization of cf2 1087 */ 1088 1089 endinittls: 1090 # endif /* 0 */ 1091 1092 /* undo damage to global variables */ 1093 if (cf2 != NULL) 1094 *--cf2 = ','; 1095 if (kf2 != NULL) 1096 *--kf2 = ','; 1097 # endif /* _FFR_TLS_1 */ 1098 1099 return ok; 1100 } 1101 /* 1102 ** TLS_GET_INFO -- get information about TLS connection 1103 ** 1104 ** Parameters: 1105 ** ssl -- TLS connection structure 1106 ** srv -- server or client 1107 ** host -- hostname of other side 1108 ** mac -- macro storage 1109 ** certreq -- did we ask for a cert? 1110 ** 1111 ** Returns: 1112 ** result of authentication. 1113 ** 1114 ** Side Effects: 1115 ** sets macros: {cipher}, {tls_version}, {verify}, 1116 ** {cipher_bits}, {alg_bits}, {cert}, {cert_subject}, 1117 ** {cert_issuer}, {cn_subject}, {cn_issuer} 1118 */ 1119 1120 int 1121 tls_get_info(ssl, srv, host, mac, certreq) 1122 SSL *ssl; 1123 bool srv; 1124 char *host; 1125 MACROS_T *mac; 1126 bool certreq; 1127 { 1128 SSL_CIPHER *c; 1129 int b, r; 1130 long verifyok; 1131 char *s, *who; 1132 char bitstr[16]; 1133 X509 *cert; 1134 1135 c = SSL_get_current_cipher(ssl); 1136 1137 /* cast is just workaround for compiler warning */ 1138 macdefine(mac, A_TEMP, macid("{cipher}"), 1139 (char *) SSL_CIPHER_get_name(c)); 1140 b = SSL_CIPHER_get_bits(c, &r); 1141 (void) sm_snprintf(bitstr, sizeof bitstr, "%d", b); 1142 macdefine(mac, A_TEMP, macid("{cipher_bits}"), bitstr); 1143 (void) sm_snprintf(bitstr, sizeof bitstr, "%d", r); 1144 macdefine(mac, A_TEMP, macid("{alg_bits}"), bitstr); 1145 s = SSL_CIPHER_get_version(c); 1146 if (s == NULL) 1147 s = "UNKNOWN"; 1148 macdefine(mac, A_TEMP, macid("{tls_version}"), s); 1149 1150 who = srv ? "server" : "client"; 1151 cert = SSL_get_peer_certificate(ssl); 1152 verifyok = SSL_get_verify_result(ssl); 1153 if (LogLevel > 14) 1154 sm_syslog(LOG_INFO, NOQID, 1155 "STARTTLS=%s, get_verify: %ld get_peer: 0x%lx", 1156 who, verifyok, (unsigned long) cert); 1157 if (cert != NULL) 1158 { 1159 unsigned int n; 1160 unsigned char md[EVP_MAX_MD_SIZE]; 1161 char buf[MAXNAME]; 1162 1163 X509_NAME_oneline(X509_get_subject_name(cert), 1164 buf, sizeof buf); 1165 macdefine(mac, A_TEMP, macid("{cert_subject}"), 1166 xtextify(buf, "<>\")")); 1167 X509_NAME_oneline(X509_get_issuer_name(cert), 1168 buf, sizeof buf); 1169 macdefine(mac, A_TEMP, macid("{cert_issuer}"), 1170 xtextify(buf, "<>\")")); 1171 X509_NAME_get_text_by_NID(X509_get_subject_name(cert), 1172 NID_commonName, buf, sizeof buf); 1173 macdefine(mac, A_TEMP, macid("{cn_subject}"), 1174 xtextify(buf, "<>\")")); 1175 X509_NAME_get_text_by_NID(X509_get_issuer_name(cert), 1176 NID_commonName, buf, sizeof buf); 1177 macdefine(mac, A_TEMP, macid("{cn_issuer}"), 1178 xtextify(buf, "<>\")")); 1179 n = 0; 1180 if (X509_digest(cert, EVP_md5(), md, &n) != 0 && n > 0) 1181 { 1182 char md5h[EVP_MAX_MD_SIZE * 3]; 1183 static const char hexcodes[] = "0123456789ABCDEF"; 1184 1185 SM_ASSERT((n * 3) + 2 < sizeof(md5h)); 1186 for (r = 0; r < (int) n; r++) 1187 { 1188 md5h[r * 3] = hexcodes[(md[r] & 0xf0) >> 4]; 1189 md5h[(r * 3) + 1] = hexcodes[(md[r] & 0x0f)]; 1190 md5h[(r * 3) + 2] = ':'; 1191 } 1192 md5h[(n * 3) - 1] = '\0'; 1193 macdefine(mac, A_TEMP, macid("{cert_md5}"), md5h); 1194 } 1195 else 1196 macdefine(mac, A_TEMP, macid("{cert_md5}"), ""); 1197 } 1198 else 1199 { 1200 macdefine(mac, A_PERM, macid("{cert_subject}"), ""); 1201 macdefine(mac, A_PERM, macid("{cert_issuer}"), ""); 1202 macdefine(mac, A_PERM, macid("{cn_subject}"), ""); 1203 macdefine(mac, A_PERM, macid("{cn_issuer}"), ""); 1204 macdefine(mac, A_TEMP, macid("{cert_md5}"), ""); 1205 } 1206 switch (verifyok) 1207 { 1208 case X509_V_OK: 1209 if (cert != NULL) 1210 { 1211 s = "OK"; 1212 r = TLS_AUTH_OK; 1213 } 1214 else 1215 { 1216 s = certreq ? "NO" : "NOT", 1217 r = TLS_AUTH_NO; 1218 } 1219 break; 1220 default: 1221 s = "FAIL"; 1222 r = TLS_AUTH_FAIL; 1223 break; 1224 } 1225 macdefine(mac, A_PERM, macid("{verify}"), s); 1226 if (cert != NULL) 1227 X509_free(cert); 1228 1229 /* do some logging */ 1230 if (LogLevel > 8) 1231 { 1232 char *vers, *s1, *s2, *cbits, *algbits; 1233 1234 vers = macget(mac, macid("{tls_version}")); 1235 cbits = macget(mac, macid("{cipher_bits}")); 1236 algbits = macget(mac, macid("{alg_bits}")); 1237 s1 = macget(mac, macid("{verify}")); 1238 s2 = macget(mac, macid("{cipher}")); 1239 1240 /* XXX: maybe cut off ident info? */ 1241 sm_syslog(LOG_INFO, NOQID, 1242 "STARTTLS=%s, relay=%.100s, version=%.16s, verify=%.16s, cipher=%.64s, bits=%.6s/%.6s", 1243 who, 1244 host == NULL ? "local" : host, 1245 vers, s1, s2, /* sm_snprintf() can deal with NULL */ 1246 algbits == NULL ? "0" : algbits, 1247 cbits == NULL ? "0" : cbits); 1248 if (LogLevel > 11) 1249 { 1250 /* 1251 ** Maybe run xuntextify on the strings? 1252 ** That is easier to read but makes it maybe a bit 1253 ** more complicated to figure out the right values 1254 ** for the access map... 1255 */ 1256 1257 s1 = macget(mac, macid("{cert_subject}")); 1258 s2 = macget(mac, macid("{cert_issuer}")); 1259 sm_syslog(LOG_INFO, NOQID, 1260 "STARTTLS=%s, cert-subject=%.256s, cert-issuer=%.256s, verifymsg=%s", 1261 who, s1, s2, 1262 X509_verify_cert_error_string(verifyok)); 1263 } 1264 } 1265 return r; 1266 } 1267 /* 1268 ** ENDTLS -- shutdown secure connection 1269 ** 1270 ** Parameters: 1271 ** ssl -- SSL connection information. 1272 ** side -- server/client (for logging). 1273 ** 1274 ** Returns: 1275 ** success? (EX_* code) 1276 */ 1277 1278 int 1279 endtls(ssl, side) 1280 SSL *ssl; 1281 char *side; 1282 { 1283 int ret = EX_OK; 1284 1285 if (ssl != NULL) 1286 { 1287 int r; 1288 1289 if ((r = SSL_shutdown(ssl)) < 0) 1290 { 1291 if (LogLevel > 11) 1292 { 1293 sm_syslog(LOG_WARNING, NOQID, 1294 "STARTTLS=%s, SSL_shutdown failed: %d", 1295 side, r); 1296 tlslogerr(side); 1297 } 1298 ret = EX_SOFTWARE; 1299 } 1300 # if !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER > 0x0090602fL 1301 1302 /* 1303 ** Bug in OpenSSL (at least up to 0.9.6b): 1304 ** From: Lutz.Jaenicke@aet.TU-Cottbus.DE 1305 ** Message-ID: <20010723152244.A13122@serv01.aet.tu-cottbus.de> 1306 ** To: openssl-users@openssl.org 1307 ** Subject: Re: SSL_shutdown() woes (fwd) 1308 ** 1309 ** The side sending the shutdown alert first will 1310 ** not care about the answer of the peer but will 1311 ** immediately return with a return value of "0" 1312 ** (ssl/s3_lib.c:ssl3_shutdown()). SSL_get_error will evaluate 1313 ** the value of "0" and as the shutdown alert of the peer was 1314 ** not received (actually, the program did not even wait for 1315 ** the answer), an SSL_ERROR_SYSCALL is flagged, because this 1316 ** is the default rule in case everything else does not apply. 1317 ** 1318 ** For your server the problem is different, because it 1319 ** receives the shutdown first (setting SSL_RECEIVED_SHUTDOWN), 1320 ** then sends its response (SSL_SENT_SHUTDOWN), so for the 1321 ** server the shutdown was successfull. 1322 ** 1323 ** As is by know, you would have to call SSL_shutdown() once 1324 ** and ignore an SSL_ERROR_SYSCALL returned. Then call 1325 ** SSL_shutdown() again to actually get the server's response. 1326 ** 1327 ** In the last discussion, Bodo Moeller concluded that a 1328 ** rewrite of the shutdown code would be necessary, but 1329 ** probably with another API, as the change would not be 1330 ** compatible to the way it is now. Things do not become 1331 ** easier as other programs do not follow the shutdown 1332 ** guidelines anyway, so that a lot error conditions and 1333 ** compitibility issues would have to be caught. 1334 ** 1335 ** For now the recommondation is to ignore the error message. 1336 */ 1337 1338 else if (r == 0) 1339 { 1340 if (LogLevel > 15) 1341 { 1342 sm_syslog(LOG_WARNING, NOQID, 1343 "STARTTLS=%s, SSL_shutdown not done", 1344 side); 1345 tlslogerr(side); 1346 } 1347 ret = EX_SOFTWARE; 1348 } 1349 # endif /* !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER > 0x0090602fL */ 1350 SSL_free(ssl); 1351 ssl = NULL; 1352 } 1353 return ret; 1354 } 1355 1356 # if !TLS_NO_RSA 1357 /* 1358 ** TMP_RSA_KEY -- return temporary RSA key 1359 ** 1360 ** Parameters: 1361 ** s -- TLS connection structure 1362 ** export -- 1363 ** keylength -- 1364 ** 1365 ** Returns: 1366 ** temporary RSA key. 1367 */ 1368 1369 # ifndef MAX_RSA_TMP_CNT 1370 # define MAX_RSA_TMP_CNT 1000 /* XXX better value? */ 1371 # endif /* ! MAX_RSA_TMP_CNT */ 1372 1373 /* ARGUSED0 */ 1374 static RSA * 1375 tmp_rsa_key(s, export, keylength) 1376 SSL *s; 1377 int export; 1378 int keylength; 1379 { 1380 # if SM_CONF_SHM 1381 extern int ShmId; 1382 extern int *PRSATmpCnt; 1383 1384 if (ShmId != SM_SHM_NO_ID && rsa_tmp != NULL && 1385 ++(*PRSATmpCnt) < MAX_RSA_TMP_CNT) 1386 return rsa_tmp; 1387 # endif /* SM_CONF_SHM */ 1388 1389 if (rsa_tmp != NULL) 1390 RSA_free(rsa_tmp); 1391 rsa_tmp = RSA_generate_key(RSA_KEYLENGTH, RSA_F4, NULL, NULL); 1392 if (rsa_tmp == NULL) 1393 { 1394 if (LogLevel > 0) 1395 sm_syslog(LOG_ERR, NOQID, 1396 "STARTTLS=server, tmp_rsa_key: RSA_generate_key failed!"); 1397 } 1398 else 1399 { 1400 # if SM_CONF_SHM 1401 # if 0 1402 /* 1403 ** XXX we can't (yet) share the new key... 1404 ** The RSA structure contains pointers hence it can't be 1405 ** easily kept in shared memory. It must be transformed 1406 ** into a continous memory region first, then stored, 1407 ** and later read out again (each time re-transformed). 1408 */ 1409 1410 if (ShmId != SM_SHM_NO_ID) 1411 *PRSATmpCnt = 0; 1412 # endif /* 0 */ 1413 # endif /* SM_CONF_SHM */ 1414 if (LogLevel > 9) 1415 sm_syslog(LOG_ERR, NOQID, 1416 "STARTTLS=server, tmp_rsa_key: new temp RSA key"); 1417 } 1418 return rsa_tmp; 1419 } 1420 # endif /* !TLS_NO_RSA */ 1421 /* 1422 ** APPS_SSL_INFO_CB -- info callback for TLS connections 1423 ** 1424 ** Parameters: 1425 ** s -- TLS connection structure 1426 ** where -- state in handshake 1427 ** ret -- return code of last operation 1428 ** 1429 ** Returns: 1430 ** none. 1431 */ 1432 1433 static void 1434 apps_ssl_info_cb(s, where, ret) 1435 CONST097 SSL *s; 1436 int where; 1437 int ret; 1438 { 1439 int w; 1440 char *str; 1441 BIO *bio_err = NULL; 1442 1443 if (LogLevel > 14) 1444 sm_syslog(LOG_INFO, NOQID, 1445 "STARTTLS: info_callback where=0x%x, ret=%d", 1446 where, ret); 1447 1448 w = where & ~SSL_ST_MASK; 1449 if (bio_err == NULL) 1450 bio_err = BIO_new_fp(stderr, BIO_NOCLOSE); 1451 1452 if (bitset(SSL_ST_CONNECT, w)) 1453 str = "SSL_connect"; 1454 else if (bitset(SSL_ST_ACCEPT, w)) 1455 str = "SSL_accept"; 1456 else 1457 str = "undefined"; 1458 1459 if (bitset(SSL_CB_LOOP, where)) 1460 { 1461 if (LogLevel > 12) 1462 sm_syslog(LOG_NOTICE, NOQID, 1463 "STARTTLS: %s:%s", 1464 str, SSL_state_string_long(s)); 1465 } 1466 else if (bitset(SSL_CB_ALERT, where)) 1467 { 1468 str = bitset(SSL_CB_READ, where) ? "read" : "write"; 1469 if (LogLevel > 12) 1470 sm_syslog(LOG_NOTICE, NOQID, 1471 "STARTTLS: SSL3 alert %s:%s:%s", 1472 str, SSL_alert_type_string_long(ret), 1473 SSL_alert_desc_string_long(ret)); 1474 } 1475 else if (bitset(SSL_CB_EXIT, where)) 1476 { 1477 if (ret == 0) 1478 { 1479 if (LogLevel > 7) 1480 sm_syslog(LOG_WARNING, NOQID, 1481 "STARTTLS: %s:failed in %s", 1482 str, SSL_state_string_long(s)); 1483 } 1484 else if (ret < 0) 1485 { 1486 if (LogLevel > 7) 1487 sm_syslog(LOG_WARNING, NOQID, 1488 "STARTTLS: %s:error in %s", 1489 str, SSL_state_string_long(s)); 1490 } 1491 } 1492 } 1493 /* 1494 ** TLS_VERIFY_LOG -- log verify error for TLS certificates 1495 ** 1496 ** Parameters: 1497 ** ok -- verify ok? 1498 ** ctx -- x509 context 1499 ** 1500 ** Returns: 1501 ** 0 -- fatal error 1502 ** 1 -- ok 1503 */ 1504 1505 static int 1506 tls_verify_log(ok, ctx, name) 1507 int ok; 1508 X509_STORE_CTX *ctx; 1509 char *name; 1510 { 1511 SSL *ssl; 1512 X509 *cert; 1513 int reason, depth; 1514 char buf[512]; 1515 1516 cert = X509_STORE_CTX_get_current_cert(ctx); 1517 reason = X509_STORE_CTX_get_error(ctx); 1518 depth = X509_STORE_CTX_get_error_depth(ctx); 1519 ssl = (SSL *) X509_STORE_CTX_get_ex_data(ctx, 1520 SSL_get_ex_data_X509_STORE_CTX_idx()); 1521 1522 if (ssl == NULL) 1523 { 1524 /* internal error */ 1525 sm_syslog(LOG_ERR, NOQID, 1526 "STARTTLS: internal error: tls_verify_cb: ssl == NULL"); 1527 return 0; 1528 } 1529 1530 X509_NAME_oneline(X509_get_subject_name(cert), buf, sizeof buf); 1531 sm_syslog(LOG_INFO, NOQID, 1532 "STARTTLS: %s cert verify: depth=%d %s, state=%d, reason=%s", 1533 name, depth, buf, ok, X509_verify_cert_error_string(reason)); 1534 return 1; 1535 } 1536 1537 /* 1538 ** TLS_VERIFY_CB -- verify callback for TLS certificates 1539 ** 1540 ** Parameters: 1541 ** ctx -- x509 context 1542 ** 1543 ** Returns: 1544 ** accept connection? 1545 ** currently: always yes. 1546 */ 1547 1548 static int 1549 # if !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER < 0x00907000L 1550 tls_verify_cb(ctx) 1551 X509_STORE_CTX *ctx; 1552 # else /* !defined() || OPENSSL_VERSION_NUMBER < 0x00907000L */ 1553 tls_verify_cb(ctx, unused) 1554 X509_STORE_CTX *ctx; 1555 void *unused; 1556 # endif /* !defined() || OPENSSL_VERSION_NUMBER < 0x00907000L */ 1557 { 1558 int ok; 1559 1560 ok = X509_verify_cert(ctx); 1561 if (ok == 0) 1562 { 1563 if (LogLevel > 13) 1564 return tls_verify_log(ok, ctx, "TLS"); 1565 return 1; /* override it */ 1566 } 1567 return ok; 1568 } 1569 /* 1570 ** TLSLOGERR -- log the errors from the TLS error stack 1571 ** 1572 ** Parameters: 1573 ** who -- server/client (for logging). 1574 ** 1575 ** Returns: 1576 ** none. 1577 */ 1578 1579 void 1580 tlslogerr(who) 1581 const char *who; 1582 { 1583 unsigned long l; 1584 int line, flags; 1585 unsigned long es; 1586 char *file, *data; 1587 char buf[256]; 1588 # define CP (const char **) 1589 1590 es = CRYPTO_thread_id(); 1591 while ((l = ERR_get_error_line_data(CP &file, &line, CP &data, &flags)) 1592 != 0) 1593 { 1594 sm_syslog(LOG_WARNING, NOQID, 1595 "STARTTLS=%s: %lu:%s:%s:%d:%s", who, es, 1596 ERR_error_string(l, buf), 1597 file, line, 1598 bitset(ERR_TXT_STRING, flags) ? data : ""); 1599 } 1600 } 1601 1602 # if OPENSSL_VERSION_NUMBER > 0x00907000L 1603 /* 1604 ** X509_VERIFY_CB -- verify callback 1605 ** 1606 ** Parameters: 1607 ** ctx -- x509 context 1608 ** 1609 ** Returns: 1610 ** accept connection? 1611 ** currently: always yes. 1612 */ 1613 1614 static int 1615 x509_verify_cb(ok, ctx) 1616 int ok; 1617 X509_STORE_CTX *ctx; 1618 { 1619 if (ok == 0) 1620 { 1621 if (LogLevel > 13) 1622 tls_verify_log(ok, ctx, "x509"); 1623 if (ctx->error == X509_V_ERR_UNABLE_TO_GET_CRL) 1624 { 1625 ctx->error = 0; 1626 return 1; /* override it */ 1627 } 1628 } 1629 return ok; 1630 } 1631 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */ 1632 #endif /* STARTTLS */ 1633