contrib/sendmail/src/tls.c

   1 /*
   2  * Copyright (c) 2000-2006, 2008, 2009, 2011, 2013-2016 Proofpoint, 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 8.127 2013-11-27 02:51:11 gshapiro Exp $")
  14
  15 #if STARTTLS
  16 # include <tls.h>
  17 # include <openssl/err.h>
  18 # include <openssl/bio.h>
  19 # include <openssl/pem.h>
  20 # ifndef HASURANDOMDEV
  21 #  include <openssl/rand.h>
  22 # endif
  23 # include <openssl/engine.h>
  24 # if _FFR_TLS_ALTNAMES
  25 #  include <openssl/x509v3.h>
  26 # endif
  27
  28 # if defined(OPENSSL_VERSION_NUMBER) && OPENSSL_VERSION_NUMBER <= 0x00907000L
  29 # ERROR: OpenSSL version OPENSSL_VERSION_NUMBER is unsupported.
  30 # endif
  31
  32 # if OPENSSL_VERSION_NUMBER >= 0x10100000L && OPENSSL_VERSION_NUMBER < 0x20000000L
  33 #  define MTA_HAVE_DH_set0_pqg 1
  34 #  define MTA_HAVE_DSA_GENERATE_EX      1
  35
  36 #  define MTA_HAVE_OPENSSL_init_ssl     1
  37 #  define MTA_ASN1_STRING_data ASN1_STRING_get0_data
  38 #  include <openssl/bn.h>
  39 #  include <openssl/dsa.h>
  40 # else
  41 #  define X509_STORE_CTX_get0_cert(ctx) (ctx)->cert
  42 #  define MTA_RSA_TMP_CB        1
  43 #  define MTA_ASN1_STRING_data ASN1_STRING_data
  44 # endif
  45
  46 # if !TLS_NO_RSA && MTA_RSA_TMP_CB
  47 static RSA *rsa_tmp = NULL;     /* temporary RSA key */
  48 static RSA *tmp_rsa_key __P((SSL *, int, int));
  49 # endif
  50 static int      tls_verify_cb __P((X509_STORE_CTX *, void *));
  51
  52 static int x509_verify_cb __P((int, X509_STORE_CTX *));
  53
  54 static void     apps_ssl_info_cb __P((const SSL *, int , int));
  55 static bool     tls_ok_f __P((char *, char *, int));
  56 static bool     tls_safe_f __P((char *, long, bool));
  57 static int      tls_verify_log __P((int, X509_STORE_CTX *, const char *));
  58
  59 int TLSsslidx = -1;
  60
  61 # if !NO_DH
  62 # include <openssl/dh.h>
  63 static DH *get_dh512 __P((void));
  64
  65 static unsigned char dh512_p[] =
  66 {
  67         0xDA,0x58,0x3C,0x16,0xD9,0x85,0x22,0x89,0xD0,0xE4,0xAF,0x75,
  68         0x6F,0x4C,0xCA,0x92,0xDD,0x4B,0xE5,0x33,0xB8,0x04,0xFB,0x0F,
  69         0xED,0x94,0xEF,0x9C,0x8A,0x44,0x03,0xED,0x57,0x46,0x50,0xD3,
  70         0x69,0x99,0xDB,0x29,0xD7,0x76,0x27,0x6B,0xA2,0xD3,0xD4,0x12,
  71         0xE2,0x18,0xF4,0xDD,0x1E,0x08,0x4C,0xF6,0xD8,0x00,0x3E,0x7C,
  72         0x47,0x74,0xE8,0x33
  73 };
  74 static unsigned char dh512_g[] =
  75 {
  76         0x02
  77 };
  78
  79 static DH *
  80 get_dh512()
  81 {
  82         DH *dh = NULL;
  83 #  if MTA_HAVE_DH_set0_pqg
  84         BIGNUM *dhp_bn, *dhg_bn;
  85 #  endif
  86
  87         if ((dh = DH_new()) == NULL)
  88                 return NULL;
  89 #  if MTA_HAVE_DH_set0_pqg
  90         dhp_bn = BN_bin2bn(dh512_p, sizeof (dh512_p), NULL);
  91         dhg_bn = BN_bin2bn(dh512_g, sizeof (dh512_g), NULL);
  92         if (dhp_bn == NULL || dhg_bn == NULL || !DH_set0_pqg(dh, dhp_bn, NULL, dhg_bn))  {
  93                 DH_free(dh);
  94                 BN_free(dhp_bn);
  95                 BN_free(dhg_bn);
  96                 return NULL;
  97         }
  98 #  else
  99         dh->p = BN_bin2bn(dh512_p, sizeof(dh512_p), NULL);
 100         dh->g = BN_bin2bn(dh512_g, sizeof(dh512_g), NULL);
 101         if ((dh->p == NULL) || (dh->g == NULL))
 102         {
 103                 DH_free(dh);
 104                 return NULL;
 105         }
 106 #  endif
 107         return dh;
 108 }
 109
 110 #  if 0
 111
 112 This is the data from which the C code has been generated:
 113
 114 -----BEGIN DH PARAMETERS-----
 115 MIIBCAKCAQEArDcgcLpxEksQHPlolRKCUJ2szKRziseWV9cUSQNZGxoGw7KkROz4
 116 HF9QSbg5axyNIG+QbZYtx0jp3l6/GWq1dLOj27yZkgYgaYgFrvKPiZ2jJ5xETQVH
 117 UpZwbjRcyjyWkWYJVsx1aF4F/iY4kT0n/+iGEoimI3C9V3KXTJ2S6jIkyJ6M/CrN
 118 EtrDynMlUMGlc7S1ouXVOTrtKeqy3S2L9eBLxVI+sChEijGIfELupdVeXihK006p
 119 MgnABPDbkTx6OOtYmSZaGQX+OLW2FPmwvcrzgCz9t9cAsuUcBZv1LeHEqZZttyLU
 120 oK0jjSXgFyeU4/NfyA+zuNeWzUL6bHmigwIBAg==
 121 -----END DH PARAMETERS-----
 122 #  endif /* 0 */
 123
 124 static DH *
 125 get_dh2048()
 126 {
 127         static unsigned char dh2048_p[]={
 128                 0xAC,0x37,0x20,0x70,0xBA,0x71,0x12,0x4B,0x10,0x1C,0xF9,0x68,
 129                 0x95,0x12,0x82,0x50,0x9D,0xAC,0xCC,0xA4,0x73,0x8A,0xC7,0x96,
 130                 0x57,0xD7,0x14,0x49,0x03,0x59,0x1B,0x1A,0x06,0xC3,0xB2,0xA4,
 131                 0x44,0xEC,0xF8,0x1C,0x5F,0x50,0x49,0xB8,0x39,0x6B,0x1C,0x8D,
 132                 0x20,0x6F,0x90,0x6D,0x96,0x2D,0xC7,0x48,0xE9,0xDE,0x5E,0xBF,
 133                 0x19,0x6A,0xB5,0x74,0xB3,0xA3,0xDB,0xBC,0x99,0x92,0x06,0x20,
 134                 0x69,0x88,0x05,0xAE,0xF2,0x8F,0x89,0x9D,0xA3,0x27,0x9C,0x44,
 135                 0x4D,0x05,0x47,0x52,0x96,0x70,0x6E,0x34,0x5C,0xCA,0x3C,0x96,
 136                 0x91,0x66,0x09,0x56,0xCC,0x75,0x68,0x5E,0x05,0xFE,0x26,0x38,
 137                 0x91,0x3D,0x27,0xFF,0xE8,0x86,0x12,0x88,0xA6,0x23,0x70,0xBD,
 138                 0x57,0x72,0x97,0x4C,0x9D,0x92,0xEA,0x32,0x24,0xC8,0x9E,0x8C,
 139                 0xFC,0x2A,0xCD,0x12,0xDA,0xC3,0xCA,0x73,0x25,0x50,0xC1,0xA5,
 140                 0x73,0xB4,0xB5,0xA2,0xE5,0xD5,0x39,0x3A,0xED,0x29,0xEA,0xB2,
 141                 0xDD,0x2D,0x8B,0xF5,0xE0,0x4B,0xC5,0x52,0x3E,0xB0,0x28,0x44,
 142                 0x8A,0x31,0x88,0x7C,0x42,0xEE,0xA5,0xD5,0x5E,0x5E,0x28,0x4A,
 143                 0xD3,0x4E,0xA9,0x32,0x09,0xC0,0x04,0xF0,0xDB,0x91,0x3C,0x7A,
 144                 0x38,0xEB,0x58,0x99,0x26,0x5A,0x19,0x05,0xFE,0x38,0xB5,0xB6,
 145                 0x14,0xF9,0xB0,0xBD,0xCA,0xF3,0x80,0x2C,0xFD,0xB7,0xD7,0x00,
 146                 0xB2,0xE5,0x1C,0x05,0x9B,0xF5,0x2D,0xE1,0xC4,0xA9,0x96,0x6D,
 147                 0xB7,0x22,0xD4,0xA0,0xAD,0x23,0x8D,0x25,0xE0,0x17,0x27,0x94,
 148                 0xE3,0xF3,0x5F,0xC8,0x0F,0xB3,0xB8,0xD7,0x96,0xCD,0x42,0xFA,
 149                 0x6C,0x79,0xA2,0x83,
 150                 };
 151         static unsigned char dh2048_g[]={ 0x02, };
 152         DH *dh;
 153 #  if MTA_HAVE_DH_set0_pqg
 154         BIGNUM *dhp_bn, *dhg_bn;
 155 #  endif
 156
 157         if ((dh=DH_new()) == NULL)
 158                 return(NULL);
 159 #  if MTA_HAVE_DH_set0_pqg
 160         dhp_bn = BN_bin2bn(dh2048_p, sizeof (dh2048_p), NULL);
 161         dhg_bn = BN_bin2bn(dh2048_g, sizeof (dh2048_g), NULL);
 162         if (dhp_bn == NULL || dhg_bn == NULL || !DH_set0_pqg(dh, dhp_bn, NULL, dhg_bn))  {
 163                 DH_free(dh);
 164                 BN_free(dhp_bn);
 165                 BN_free(dhg_bn);
 166                 return NULL;
 167         }
 168 #  else
 169         dh->p=BN_bin2bn(dh2048_p,sizeof(dh2048_p),NULL);
 170         dh->g=BN_bin2bn(dh2048_g,sizeof(dh2048_g),NULL);
 171         if ((dh->p == NULL) || (dh->g == NULL))
 172         {
 173                 DH_free(dh);
 174                 return(NULL);
 175         }
 176 #  endif
 177         return(dh);
 178 }
 179 # endif /* !NO_DH */
 180
 181
 182 /*
 183 **  TLS_RAND_INIT -- initialize STARTTLS random generator
 184 **
 185 **      Parameters:
 186 **              randfile -- name of file with random data
 187 **              logl -- loglevel
 188 **
 189 **      Returns:
 190 **              success/failure
 191 **
 192 **      Side Effects:
 193 **              initializes PRNG for tls library.
 194 */
 195
 196 # define MIN_RAND_BYTES 128     /* 1024 bits */
 197
 198 # define RF_OK          0       /* randfile OK */
 199 # define RF_MISS        1       /* randfile == NULL || *randfile == '\0' */
 200 # define RF_UNKNOWN     2       /* unknown prefix for randfile */
 201
 202 # define RI_NONE        0       /* no init yet */
 203 # define RI_SUCCESS     1       /* init was successful */
 204 # define RI_FAIL        2       /* init failed */
 205
 206 static bool     tls_rand_init __P((char *, int));
 207
 208 static bool
 209 tls_rand_init(randfile, logl)
 210         char *randfile;
 211         int logl;
 212 {
 213 # ifndef HASURANDOMDEV
 214         /* not required if /dev/urandom exists, OpenSSL does it internally */
 215
 216         bool ok;
 217         int randdef;
 218         static int done = RI_NONE;
 219
 220         /*
 221         **  initialize PRNG
 222         */
 223
 224         /* did we try this before? if yes: return old value */
 225         if (done != RI_NONE)
 226                 return done == RI_SUCCESS;
 227
 228         /* set default values */
 229         ok = false;
 230         done = RI_FAIL;
 231         randdef = (randfile == NULL || *randfile == '\0') ? RF_MISS : RF_OK;
 232 #  if EGD
 233         if (randdef == RF_OK && sm_strncasecmp(randfile, "egd:", 4) == 0)
 234         {
 235                 randfile += 4;
 236                 if (RAND_egd(randfile) < 0)
 237                 {
 238                         sm_syslog(LOG_WARNING, NOQID,
 239                                   "STARTTLS: RAND_egd(%s) failed: random number generator not seeded",
 240                                    randfile);
 241                 }
 242                 else
 243                         ok = true;
 244         }
 245         else
 246 #  endif /* EGD */
 247         if (randdef == RF_OK && sm_strncasecmp(randfile, "file:", 5) == 0)
 248         {
 249                 int fd;
 250                 long sff;
 251                 struct stat st;
 252
 253                 randfile += 5;
 254                 sff = SFF_SAFEDIRPATH | SFF_NOWLINK
 255                       | SFF_NOGWFILES | SFF_NOWWFILES
 256                       | SFF_NOGRFILES | SFF_NOWRFILES
 257                       | SFF_MUSTOWN | SFF_ROOTOK | SFF_OPENASROOT;
 258                 if (DontLockReadFiles)
 259                         sff |= SFF_NOLOCK;
 260                 if ((fd = safeopen(randfile, O_RDONLY, 0, sff)) >= 0)
 261                 {
 262                         if (fstat(fd, &st) < 0)
 263                         {
 264                                 if (LogLevel > logl)
 265                                         sm_syslog(LOG_ERR, NOQID,
 266                                                   "STARTTLS: can't fstat(%s)",
 267                                                   randfile);
 268                         }
 269                         else
 270                         {
 271                                 bool use, problem;
 272
 273                                 use = true;
 274                                 problem = false;
 275
 276                                 /* max. age of file: 10 minutes */
 277                                 if (st.st_mtime + 600 < curtime())
 278                                 {
 279                                         use = bitnset(DBS_INSUFFICIENTENTROPY,
 280                                                       DontBlameSendmail);
 281                                         problem = true;
 282                                         if (LogLevel > logl)
 283                                                 sm_syslog(LOG_ERR, NOQID,
 284                                                           "STARTTLS: RandFile %s too old: %s",
 285                                                           randfile,
 286                                                           use ? "unsafe" :
 287                                                                 "unusable");
 288                                 }
 289                                 if (use && st.st_size < MIN_RAND_BYTES)
 290                                 {
 291                                         use = bitnset(DBS_INSUFFICIENTENTROPY,
 292                                                       DontBlameSendmail);
 293                                         problem = true;
 294                                         if (LogLevel > logl)
 295                                                 sm_syslog(LOG_ERR, NOQID,
 296                                                           "STARTTLS: size(%s) < %d: %s",
 297                                                           randfile,
 298                                                           MIN_RAND_BYTES,
 299                                                           use ? "unsafe" :
 300                                                                 "unusable");
 301                                 }
 302                                 if (use)
 303                                         ok = RAND_load_file(randfile, -1) >=
 304                                              MIN_RAND_BYTES;
 305                                 if (use && !ok)
 306                                 {
 307                                         if (LogLevel > logl)
 308                                                 sm_syslog(LOG_WARNING, NOQID,
 309                                                           "STARTTLS: RAND_load_file(%s) failed: random number generator not seeded",
 310                                                           randfile);
 311                                 }
 312                                 if (problem)
 313                                         ok = false;
 314                         }
 315                         if (ok || bitnset(DBS_INSUFFICIENTENTROPY,
 316                                           DontBlameSendmail))
 317                         {
 318                                 /* add this even if fstat() failed */
 319                                 RAND_seed((void *) &st, sizeof(st));
 320                         }
 321                         (void) close(fd);
 322                 }
 323                 else
 324                 {
 325                         if (LogLevel > logl)
 326                                 sm_syslog(LOG_WARNING, NOQID,
 327                                           "STARTTLS: Warning: safeopen(%s) failed",
 328                                           randfile);
 329                 }
 330         }
 331         else if (randdef == RF_OK)
 332         {
 333                 if (LogLevel > logl)
 334                         sm_syslog(LOG_WARNING, NOQID,
 335                                   "STARTTLS: Error: no proper random file definition %s",
 336                                   randfile);
 337                 randdef = RF_UNKNOWN;
 338         }
 339         if (randdef == RF_MISS)
 340         {
 341                 if (LogLevel > logl)
 342                         sm_syslog(LOG_WARNING, NOQID,
 343                                   "STARTTLS: Error: missing random file definition");
 344         }
 345         if (!ok && bitnset(DBS_INSUFFICIENTENTROPY, DontBlameSendmail))
 346         {
 347                 int i;
 348                 long r;
 349                 unsigned char buf[MIN_RAND_BYTES];
 350
 351                 /* assert((MIN_RAND_BYTES % sizeof(long)) == 0); */
 352                 for (i = 0; i <= sizeof(buf) - sizeof(long); i += sizeof(long))
 353                 {
 354                         r = get_random();
 355                         (void) memcpy(buf + i, (void *) &r, sizeof(long));
 356                 }
 357                 RAND_seed(buf, sizeof(buf));
 358                 if (LogLevel > logl)
 359                         sm_syslog(LOG_WARNING, NOQID,
 360                                   "STARTTLS: Warning: random number generator not properly seeded");
 361                 ok = true;
 362         }
 363         done = ok ? RI_SUCCESS : RI_FAIL;
 364         return ok;
 365 # else /* ! HASURANDOMDEV */
 366         return true;
 367 # endif /* ! HASURANDOMDEV */
 368 }
 369 /*
 370 **  INIT_TLS_LIBRARY -- Calls functions which setup TLS library for global use.
 371 **
 372 **      Parameters:
 373 **              fipsmode -- use FIPS?
 374 **
 375 **      Returns:
 376 **              0: OK
 377 **              <0: perm.fail
 378 **              >0: fail but can continue
 379 */
 380
 381 int
 382 init_tls_library(fipsmode)
 383         bool fipsmode;
 384 {
 385         bool bv;
 386
 387         /*
 388         **  OPENSSL_init_ssl(3): "As of version 1.1.0 OpenSSL will
 389         **  automatically allocate all resources that it needs
 390         **  so no explicit initialisation is required."
 391         */
 392
 393 # if !MTA_HAVE_OPENSSL_init_ssl
 394         /* basic TLS initialization, ignore result for now */
 395         SSL_library_init();
 396         SSL_load_error_strings();
 397         OpenSSL_add_all_algorithms();
 398 # endif
 399
 400         bv = true;
 401         if (TLSsslidx < 0)
 402         {
 403                 TLSsslidx = SSL_get_ex_new_index(0, 0, 0, 0, 0);
 404                 if (TLSsslidx < 0)
 405                 {
 406                         if (LogLevel > 0)
 407                                 sm_syslog(LOG_ERR, NOQID,
 408                                         "STARTTLS=init, SSL_get_ex_new_index=%d",
 409                                         TLSsslidx);
 410                         bv = false;
 411                 }
 412         }
 413
 414         if (bv)
 415                 bv = tls_rand_init(RandFile, 7);
 416 # if _FFR_FIPSMODE
 417         if (bv && fipsmode)
 418         {
 419                 if (!FIPS_mode_set(1))
 420                 {
 421                         unsigned long err;
 422
 423                         err = ERR_get_error();
 424                         if (LogLevel > 0)
 425                                 sm_syslog(LOG_ERR, NOQID,
 426                                         "STARTTLS=init, FIPSMode=%s",
 427                                         ERR_error_string(err, NULL));
 428                         return -1;
 429                 }
 430                 else
 431                 {
 432                         if (LogLevel > 9)
 433                                 sm_syslog(LOG_INFO, NOQID,
 434                                         "STARTTLS=init, FIPSMode=ok");
 435                 }
 436                 if (CertFingerprintAlgorithm == NULL)
 437                         CertFingerprintAlgorithm = "sha1";
 438         }
 439 # endif /* _FFR_FIPSMODE  */
 440
 441         if (!TLS_set_engine(SSLEngine, true))
 442         {
 443                 if (LogLevel > 0)
 444                         sm_syslog(LOG_ERR, NOQID,
 445                                   "STARTTLS=init, engine=%s, TLS_set_engine=failed",
 446                                   SSLEngine);
 447                 return -1;
 448         }
 449
 450         if (bv && CertFingerprintAlgorithm != NULL)
 451         {
 452                 const EVP_MD *md;
 453
 454                 md = EVP_get_digestbyname(CertFingerprintAlgorithm);
 455                 if (NULL == md)
 456                 {
 457                         bv = false;
 458                         if (LogLevel > 0)
 459                                 sm_syslog(LOG_ERR, NOQID,
 460                                         "STARTTLS=init, CertFingerprintAlgorithm=%s, status=invalid"
 461                                         , CertFingerprintAlgorithm);
 462                 }
 463                 else
 464                         EVP_digest = md;
 465         }
 466         return bv ? 0 : 1;
 467 }
 468
 469 /*
 470 **  TLS_SET_VERIFY -- request client certificate?
 471 **
 472 **      Parameters:
 473 **              ctx -- TLS context
 474 **              ssl -- TLS session context
 475 **              vrfy -- request certificate?
 476 **
 477 **      Returns:
 478 **              none.
 479 **
 480 **      Side Effects:
 481 **              Sets verification state for TLS
 482 **
 483 # if TLS_VRFY_PER_CTX
 484 **      Notice:
 485 **              This is per TLS context, not per TLS structure;
 486 **              the former is global, the latter per connection.
 487 **              It would be nice to do this per connection, but this
 488 **              doesn't work in the current TLS libraries :-(
 489 # endif * TLS_VRFY_PER_CTX *
 490 */
 491
 492 void
 493 tls_set_verify(ctx, ssl, vrfy)
 494         SSL_CTX *ctx;
 495         SSL *ssl;
 496         bool vrfy;
 497 {
 498 # if !TLS_VRFY_PER_CTX
 499         SSL_set_verify(ssl, vrfy ? SSL_VERIFY_PEER : SSL_VERIFY_NONE, NULL);
 500 # else
 501         SSL_CTX_set_verify(ctx, vrfy ? SSL_VERIFY_PEER : SSL_VERIFY_NONE,
 502                         NULL);
 503 # endif
 504 }
 505
 506 /*
 507 **  status in initialization
 508 **  these flags keep track of the status of the initialization
 509 **  i.e., whether a file exists (_EX) and whether it can be used (_OK)
 510 **  [due to permissions]
 511 */
 512
 513 # define TLS_S_NONE     0x00000000      /* none yet */
 514 # define TLS_S_CERT_EX  0x00000001      /* cert file exists */
 515 # define TLS_S_CERT_OK  0x00000002      /* cert file is ok */
 516 # define TLS_S_KEY_EX   0x00000004      /* key file exists */
 517 # define TLS_S_KEY_OK   0x00000008      /* key file is ok */
 518 # define TLS_S_CERTP_EX 0x00000010      /* CA cert path exists */
 519 # define TLS_S_CERTP_OK 0x00000020      /* CA cert path is ok */
 520 # define TLS_S_CERTF_EX 0x00000040      /* CA cert file exists */
 521 # define TLS_S_CERTF_OK 0x00000080      /* CA cert file is ok */
 522 # define TLS_S_CRLF_EX  0x00000100      /* CRL file exists */
 523 # define TLS_S_CRLF_OK  0x00000200      /* CRL file is ok */
 524
 525 # define TLS_S_CERT2_EX 0x00001000      /* 2nd cert file exists */
 526 # define TLS_S_CERT2_OK 0x00002000      /* 2nd cert file is ok */
 527 # define TLS_S_KEY2_EX  0x00004000      /* 2nd key file exists */
 528 # define TLS_S_KEY2_OK  0x00008000      /* 2nd key file is ok */
 529
 530 # define TLS_S_DH_OK    0x00200000      /* DH cert is ok */
 531 # define TLS_S_DHPAR_EX 0x00400000      /* DH param file exists */
 532 # define TLS_S_DHPAR_OK 0x00800000      /* DH param file is ok to use */
 533
 534 /* Type of variable */
 535 # define TLS_T_OTHER    0
 536 # define TLS_T_SRV      1
 537 # define TLS_T_CLT      2
 538
 539 /*
 540 **  TLS_OK_F -- can var be an absolute filename?
 541 **
 542 **      Parameters:
 543 **              var -- filename
 544 **              fn -- what is the filename used for?
 545 **              type -- type of variable
 546 **
 547 **      Returns:
 548 **              ok?
 549 */
 550
 551 static bool
 552 tls_ok_f(var, fn, type)
 553         char *var;
 554         char *fn;
 555         int type;
 556 {
 557         /* must be absolute pathname */
 558         if (var != NULL && *var == '/')
 559                 return true;
 560         if (LogLevel > 12)
 561                 sm_syslog(LOG_WARNING, NOQID, "STARTTLS: %s%s missing",
 562                           type == TLS_T_SRV ? "Server" :
 563                           (type == TLS_T_CLT ? "Client" : ""), fn);
 564         return false;
 565 }
 566 /*
 567 **  TLS_SAFE_F -- is a file safe to use?
 568 **
 569 **      Parameters:
 570 **              var -- filename
 571 **              sff -- flags for safefile()
 572 **              srv -- server side?
 573 **
 574 **      Returns:
 575 **              ok?
 576 */
 577
 578 static bool
 579 tls_safe_f(var, sff, srv)
 580         char *var;
 581         long sff;
 582         bool srv;
 583 {
 584         int ret;
 585
 586         if ((ret = safefile(var, RunAsUid, RunAsGid, RunAsUserName, sff,
 587                             S_IRUSR, NULL)) == 0)
 588                 return true;
 589         if (LogLevel > 7)
 590                 sm_syslog(LOG_WARNING, NOQID, "STARTTLS=%s: file %s unsafe: %s",
 591                           srv ? "server" : "client", var, sm_errstring(ret));
 592         return false;
 593 }
 594
 595 /*
 596 **  TLS_OK_F -- macro to simplify calls to tls_ok_f
 597 **
 598 **      Parameters:
 599 **              var -- filename
 600 **              fn -- what is the filename used for?
 601 **              req -- is the file required?
 602 **              st -- status bit to set if ok
 603 **              type -- type of variable
 604 **
 605 **      Side Effects:
 606 **              uses r, ok; may change ok and status.
 607 **
 608 */
 609
 610 # define TLS_OK_F(var, fn, req, st, type) if (ok) \
 611         { \
 612                 r = tls_ok_f(var, fn, type); \
 613                 if (r) \
 614                         status |= st; \
 615                 else if (req) \
 616                         ok = false; \
 617         }
 618
 619 /*
 620 **  TLS_UNR -- macro to return whether a file should be unreadable
 621 **
 622 **      Parameters:
 623 **              bit -- flag to test
 624 **              req -- flags
 625 **
 626 **      Returns:
 627 **              0/SFF_NORFILES
 628 */
 629
 630 # define TLS_UNR(bit, req)      (bitset(bit, req) ? SFF_NORFILES : 0)
 631 # define TLS_OUNR(bit, req)     (bitset(bit, req) ? SFF_NOWRFILES : 0)
 632 # define TLS_KEYSFF(req)        \
 633         (bitnset(DBS_GROUPREADABLEKEYFILE, DontBlameSendmail) ? \
 634                 TLS_OUNR(TLS_I_KEY_OUNR, req) :                 \
 635                 TLS_UNR(TLS_I_KEY_UNR, req))
 636
 637 /*
 638 **  TLS_SAFE_F -- macro to simplify calls to tls_safe_f
 639 **
 640 **      Parameters:
 641 **              var -- filename
 642 **              sff -- flags for safefile()
 643 **              req -- is the file required?
 644 **              ex -- does the file exist?
 645 **              st -- status bit to set if ok
 646 **              srv -- server side?
 647 **
 648 **      Side Effects:
 649 **              uses r, ok, ex; may change ok and status.
 650 **
 651 */
 652
 653 # define TLS_SAFE_F(var, sff, req, ex, st, srv) if (ex && ok) \
 654         { \
 655                 r = tls_safe_f(var, sff, srv); \
 656                 if (r) \
 657                         status |= st;   \
 658                 else if (req) \
 659                         ok = false;     \
 660         }
 661
 662 /*
 663 **  LOAD_CERTKEY -- load cert/key for TLS session
 664 **
 665 **      Parameters:
 666 **              ssl -- TLS session context
 667 **              srv -- server side?
 668 **              certfile -- filename of certificate
 669 **              keyfile -- filename of private key
 670 **
 671 **      Returns:
 672 **              succeeded?
 673 */
 674
 675 bool
 676 load_certkey(ssl, srv, certfile, keyfile)
 677         SSL *ssl;
 678         bool srv;
 679         char *certfile;
 680         char *keyfile;
 681 {
 682         bool ok;
 683         int r;
 684         long sff, status;
 685         unsigned long req;
 686         char *who;
 687
 688         ok = true;
 689         who = srv ? "server" : "client";
 690         status = TLS_S_NONE;
 691         req = TLS_I_CERT_EX|TLS_I_KEY_EX;
 692         TLS_OK_F(certfile, "CertFile", bitset(TLS_I_CERT_EX, req),
 693                  TLS_S_CERT_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 694         TLS_OK_F(keyfile, "KeyFile", bitset(TLS_I_KEY_EX, req),
 695                  TLS_S_KEY_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 696
 697         /* certfile etc. must be "safe". */
 698         sff = SFF_REGONLY | SFF_SAFEDIRPATH | SFF_NOWLINK
 699              | SFF_NOGWFILES | SFF_NOWWFILES
 700              | SFF_MUSTOWN | SFF_ROOTOK | SFF_OPENASROOT;
 701         if (DontLockReadFiles)
 702                 sff |= SFF_NOLOCK;
 703
 704         TLS_SAFE_F(certfile, sff | TLS_UNR(TLS_I_CERT_UNR, req),
 705                    bitset(TLS_I_CERT_EX, req),
 706                    bitset(TLS_S_CERT_EX, status), TLS_S_CERT_OK, srv);
 707         TLS_SAFE_F(keyfile, sff | TLS_KEYSFF(req),
 708                    bitset(TLS_I_KEY_EX, req),
 709                    bitset(TLS_S_KEY_EX, status), TLS_S_KEY_OK, srv);
 710
 711 # define SSL_use_cert(ssl, certfile) \
 712         SSL_use_certificate_file(ssl, certfile, SSL_FILETYPE_PEM)
 713 # define SSL_USE_CERT "SSL_use_certificate_file"
 714
 715         if (bitset(TLS_S_CERT_OK, status) &&
 716             SSL_use_cert(ssl, certfile) <= 0)
 717         {
 718                 if (LogLevel > 7)
 719                 {
 720                         sm_syslog(LOG_WARNING, NOQID,
 721                                   "STARTTLS=%s, error: %s(%s) failed",
 722                                   who, SSL_USE_CERT, certfile);
 723                         tlslogerr(LOG_WARNING, 9, who);
 724                 }
 725                 if (bitset(TLS_I_USE_CERT, req))
 726                         return false;
 727         }
 728         if (bitset(TLS_S_KEY_OK, status) &&
 729             SSL_use_PrivateKey_file(ssl, keyfile, SSL_FILETYPE_PEM) <= 0)
 730         {
 731                 if (LogLevel > 7)
 732                 {
 733                         sm_syslog(LOG_WARNING, NOQID,
 734                                   "STARTTLS=%s, error: SSL_use_PrivateKey_file(%s) failed",
 735                                   who, keyfile);
 736                         tlslogerr(LOG_WARNING, 9, who);
 737                 }
 738                 if (bitset(TLS_I_USE_KEY, req))
 739                         return false;
 740         }
 741
 742         /* check the private key */
 743         if (bitset(TLS_S_KEY_OK, status) &&
 744             (r = SSL_check_private_key(ssl)) <= 0)
 745         {
 746                 /* Private key does not match the certificate public key */
 747                 if (LogLevel > 5)
 748                 {
 749                         sm_syslog(LOG_WARNING, NOQID,
 750                                   "STARTTLS=%s, error: SSL_check_private_key failed(%s): %d",
 751                                   who, keyfile, r);
 752                         tlslogerr(LOG_WARNING, 9, who);
 753                 }
 754                 if (bitset(TLS_I_USE_KEY, req))
 755                         return false;
 756         }
 757
 758         return true;
 759 }
 760
 761 /*
 762 **  LOAD_CRLFILE -- load a file holding a CRL into the TLS context
 763 **
 764 **      Parameters:
 765 **              ctx -- TLS context
 766 **              srv -- server side?
 767 **              filename -- filename of CRL
 768 **
 769 **      Returns:
 770 **              succeeded?
 771 */
 772
 773 static bool load_crlfile __P((SSL_CTX *, bool, char *));
 774
 775 static bool
 776 load_crlfile(ctx, srv, filename)
 777         SSL_CTX *ctx;
 778         bool srv;
 779         char *filename;
 780 {
 781         char *who;
 782         BIO *crl_file;
 783         X509_CRL *crl;
 784         X509_STORE *store;
 785
 786         who = srv ? "server" : "client";
 787         crl_file = BIO_new(BIO_s_file());
 788         if (crl_file == NULL)
 789         {
 790                 if (LogLevel > 9)
 791                         sm_syslog(LOG_WARNING, NOQID,
 792                                   "STARTTLS=%s, error: BIO_new=failed", who);
 793                 return false;
 794         }
 795
 796         if (BIO_read_filename(crl_file, filename) < 0)
 797         {
 798                 if (LogLevel > 9)
 799                         sm_syslog(LOG_WARNING, NOQID,
 800                                   "STARTTLS=%s, error: BIO_read_filename(%s)=failed",
 801                                   who, filename);
 802
 803                 /* avoid memory leaks */
 804                 BIO_free(crl_file);
 805                 return false;
 806         }
 807
 808         crl = PEM_read_bio_X509_CRL(crl_file, NULL, NULL, NULL);
 809         if (crl == NULL)
 810         {
 811                 if (LogLevel > 9)
 812                         sm_syslog(LOG_WARNING, NOQID,
 813                                   "STARTTLS=%s, error: PEM_read_bio_X509_CRL(%s)=failed",
 814                                   who, filename);
 815                 BIO_free(crl_file);
 816                 return true;    /* XXX should probably be 'false' */
 817         }
 818
 819         BIO_free(crl_file);
 820
 821         /* get a pointer to the current certificate validation store */
 822         store = SSL_CTX_get_cert_store(ctx);    /* does not fail */
 823
 824         if (X509_STORE_add_crl(store, crl) == 0)
 825         {
 826                 if (LogLevel > 9)
 827                         sm_syslog(LOG_WARNING, NOQID,
 828                                   "STARTTLS=%s, error: X509_STORE_add_crl=failed",
 829                                   who);
 830                 X509_CRL_free(crl);
 831                 return false;
 832         }
 833
 834         X509_CRL_free(crl);
 835
 836         X509_STORE_set_flags(store,
 837                 X509_V_FLAG_CRL_CHECK|X509_V_FLAG_CRL_CHECK_ALL);
 838         X509_STORE_set_verify_cb_func(store, x509_verify_cb);
 839
 840         return true;
 841 }
 842
 843 /*
 844 **  LOAD_CRLPATH -- configure the TLS context to lookup CRLs in a directory
 845 **
 846 **      Parameters:
 847 **              ctx -- TLS context
 848 **              srv -- server side?
 849 **              path -- path of hashed directory of CRLs
 850 **
 851 **      Returns:
 852 **              succeeded?
 853 */
 854
 855 static bool load_crlpath __P((SSL_CTX *, bool, char *));
 856
 857 static bool
 858 load_crlpath(ctx, srv, path)
 859         SSL_CTX *ctx;
 860         bool srv;
 861         char *path;
 862 {
 863         char *who;
 864         X509_STORE *store;
 865         X509_LOOKUP *lookup;
 866
 867         who = srv ? "server" : "client";
 868
 869         /* get a pointer to the current certificate validation store */
 870         store = SSL_CTX_get_cert_store(ctx);    /* does not fail */
 871
 872         lookup = X509_STORE_add_lookup(store, X509_LOOKUP_hash_dir());
 873         if (lookup == NULL)
 874         {
 875                 if (LogLevel > 9)
 876                         sm_syslog(LOG_WARNING, NOQID,
 877                                   "STARTTLS=%s, error: X509_STORE_add_lookup(hash)=failed",
 878                                   who);
 879                 return false;
 880         }
 881
 882         if (X509_LOOKUP_add_dir(lookup, path, X509_FILETYPE_PEM) == 0)
 883         {
 884                 if (LogLevel > 9)
 885                         sm_syslog(LOG_WARNING, NOQID,
 886                                   "STARTTLS=%s, error: X509_LOOKUP_add_dir(%s)=failed",
 887                                   who, path);
 888                 return false;
 889         }
 890
 891         X509_STORE_set_flags(store,
 892                 X509_V_FLAG_CRL_CHECK|X509_V_FLAG_CRL_CHECK_ALL);
 893         X509_STORE_set_verify_cb_func(store, x509_verify_cb);
 894
 895         return true;
 896 }
 897
 898 /*
 899 **  INITTLS -- initialize TLS
 900 **
 901 **      Parameters:
 902 **              ctx -- pointer to context
 903 **              req -- requirements for initialization (see sendmail.h)
 904 **              options -- options
 905 **              srv -- server side?
 906 **              certfile -- filename of certificate
 907 **              keyfile -- filename of private key
 908 **              cacertpath -- path to CAs
 909 **              cacertfile -- file with CA(s)
 910 **              dhparam -- parameters for DH
 911 **
 912 **      Returns:
 913 **              succeeded?
 914 */
 915
 916 /*
 917 **  The session_id_context identifies the service that created a session.
 918 **  This information is used to distinguish between multiple TLS-based
 919 **  servers running on the same server. We use the name of the mail system.
 920 **  Note: the session cache is not persistent.
 921 */
 922
 923 static char server_session_id_context[] = "sendmail8";
 924
 925 /* 0.9.8a and b have a problem with SSL_OP_TLS_BLOCK_PADDING_BUG */
 926 # if (OPENSSL_VERSION_NUMBER >= 0x0090800fL)
 927 #  define SM_SSL_OP_TLS_BLOCK_PADDING_BUG       1
 928 # else
 929 #  define SM_SSL_OP_TLS_BLOCK_PADDING_BUG       0
 930 # endif
 931
 932 bool
 933 inittls(ctx, req, options, srv, certfile, keyfile, cacertpath, cacertfile, dhparam)
 934         SSL_CTX **ctx;
 935         unsigned long req;
 936         unsigned long options;
 937         bool srv;
 938         char *certfile, *keyfile, *cacertpath, *cacertfile, *dhparam;
 939 {
 940 # if !NO_DH
 941         static DH *dh = NULL;
 942 # endif
 943         int r;
 944         bool ok;
 945         long sff, status;
 946         char *who;
 947         char *cf2, *kf2;
 948 # if SM_CONF_SHM && !TLS_NO_RSA && MTA_RSA_TMP_CB
 949         extern int ShmId;
 950 # endif
 951 # if SM_SSL_OP_TLS_BLOCK_PADDING_BUG
 952         long rt_version;
 953         STACK_OF(SSL_COMP) *comp_methods;
 954 # endif
 955
 956         status = TLS_S_NONE;
 957         who = srv ? "server" : "client";
 958         if (ctx == NULL)
 959         {
 960                 syserr("STARTTLS=%s, inittls: ctx == NULL", who);
 961                 /* NOTREACHED */
 962                 SM_ASSERT(ctx != NULL);
 963         }
 964
 965         /* already initialized? (we could re-init...) */
 966         if (*ctx != NULL)
 967                 return true;
 968         ok = true;
 969
 970         /*
 971         **  look for a second filename: it must be separated by a ','
 972         **  no blanks allowed (they won't be skipped).
 973         **  we change a global variable here! this change will be undone
 974         **  before return from the function but only if it returns true.
 975         **  this isn't a problem since in a failure case this function
 976         **  won't be called again with the same (overwritten) values.
 977         **  otherwise each return must be replaced with a goto endinittls.
 978         */
 979
 980         cf2 = NULL;
 981         kf2 = NULL;
 982         if (certfile != NULL && (cf2 = strchr(certfile, ',')) != NULL)
 983         {
 984                 *cf2++ = '\0';
 985                 if (keyfile != NULL && (kf2 = strchr(keyfile, ',')) != NULL)
 986                         *kf2++ = '\0';
 987         }
 988
 989         /*
 990         **  Check whether files/paths are defined
 991         */
 992
 993         TLS_OK_F(certfile, "CertFile", bitset(TLS_I_CERT_EX, req),
 994                  TLS_S_CERT_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 995         TLS_OK_F(keyfile, "KeyFile", bitset(TLS_I_KEY_EX, req),
 996                  TLS_S_KEY_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 997         TLS_OK_F(cacertpath, "CACertPath", bitset(TLS_I_CERTP_EX, req),
 998                  TLS_S_CERTP_EX, TLS_T_OTHER);
 999         TLS_OK_F(cacertfile, "CACertFile", bitset(TLS_I_CERTF_EX, req),
1000                  TLS_S_CERTF_EX, TLS_T_OTHER);
1001
1002         TLS_OK_F(CRLFile, "CRLFile", bitset(TLS_I_CRLF_EX, req),
1003                  TLS_S_CRLF_EX, TLS_T_OTHER);
1004
1005         /*
1006         **  if the second file is specified it must exist
1007         **  XXX: it is possible here to define only one of those files
1008         */
1009
1010         if (cf2 != NULL)
1011         {
1012                 TLS_OK_F(cf2, "CertFile", bitset(TLS_I_CERT_EX, req),
1013                          TLS_S_CERT2_EX, srv ? TLS_T_SRV : TLS_T_CLT);
1014         }
1015         if (kf2 != NULL)
1016         {
1017                 TLS_OK_F(kf2, "KeyFile", bitset(TLS_I_KEY_EX, req),
1018                          TLS_S_KEY2_EX, srv ? TLS_T_SRV : TLS_T_CLT);
1019         }
1020
1021         /*
1022         **  valid values for dhparam are (only the first char is checked)
1023         **  none        no parameters: don't use DH
1024         **  i           use precomputed 2048 bit parameters
1025         **  512         use precomputed 512 bit parameters
1026         **  1024        generate 1024 bit parameters
1027         **  2048        generate 2048 bit parameters
1028         **  /file/name  read parameters from /file/name
1029         */
1030
1031 # define SET_DH_DFL     \
1032         do {    \
1033                 dhparam = "I";  \
1034                 req |= TLS_I_DHFIXED;   \
1035         } while (0)
1036
1037         if (bitset(TLS_I_TRY_DH, req))
1038         {
1039                 if (dhparam != NULL)
1040                 {
1041                         char c = *dhparam;
1042
1043                         if (c == '1')
1044                                 req |= TLS_I_DH1024;
1045                         else if (c == 'I' || c == 'i')
1046                                 req |= TLS_I_DHFIXED;
1047                         else if (c == '2')
1048                                 req |= TLS_I_DH2048;
1049                         else if (c == '5')
1050                                 req |= TLS_I_DH512;
1051                         else if (c == 'n' || c == 'N')
1052                                 req &= ~TLS_I_TRY_DH;
1053                         else if (c != '/')
1054                         {
1055                                 if (LogLevel > 12)
1056                                         sm_syslog(LOG_WARNING, NOQID,
1057                                                   "STARTTLS=%s, error: illegal value '%s' for DHParameters",
1058                                                   who, dhparam);
1059                                 dhparam = NULL;
1060                         }
1061                 }
1062                 if (dhparam == NULL)
1063                         SET_DH_DFL;
1064                 else if (*dhparam == '/')
1065                 {
1066                         TLS_OK_F(dhparam, "DHParameters",
1067                                  bitset(TLS_I_DHPAR_EX, req),
1068                                  TLS_S_DHPAR_EX, TLS_T_OTHER);
1069                 }
1070         }
1071         if (!ok)
1072                 return ok;
1073
1074         /* certfile etc. must be "safe". */
1075         sff = SFF_REGONLY | SFF_SAFEDIRPATH | SFF_NOWLINK
1076              | SFF_NOGWFILES | SFF_NOWWFILES
1077              | SFF_MUSTOWN | SFF_ROOTOK | SFF_OPENASROOT;
1078         if (DontLockReadFiles)
1079                 sff |= SFF_NOLOCK;
1080
1081         TLS_SAFE_F(certfile, sff | TLS_UNR(TLS_I_CERT_UNR, req),
1082                    bitset(TLS_I_CERT_EX, req),
1083                    bitset(TLS_S_CERT_EX, status), TLS_S_CERT_OK, srv);
1084         TLS_SAFE_F(keyfile, sff | TLS_KEYSFF(req),
1085                    bitset(TLS_I_KEY_EX, req),
1086                    bitset(TLS_S_KEY_EX, status), TLS_S_KEY_OK, srv);
1087         TLS_SAFE_F(cacertfile, sff | TLS_UNR(TLS_I_CERTF_UNR, req),
1088                    bitset(TLS_I_CERTF_EX, req),
1089                    bitset(TLS_S_CERTF_EX, status), TLS_S_CERTF_OK, srv);
1090         if (dhparam != NULL && *dhparam == '/')
1091         {
1092                 TLS_SAFE_F(dhparam, sff | TLS_UNR(TLS_I_DHPAR_UNR, req),
1093                            bitset(TLS_I_DHPAR_EX, req),
1094                            bitset(TLS_S_DHPAR_EX, status), TLS_S_DHPAR_OK, srv);
1095                 if (!bitset(TLS_S_DHPAR_OK, status))
1096                         SET_DH_DFL;
1097         }
1098         TLS_SAFE_F(CRLFile, sff | TLS_UNR(TLS_I_CRLF_UNR, req),
1099                    bitset(TLS_I_CRLF_EX, req),
1100                    bitset(TLS_S_CRLF_EX, status), TLS_S_CRLF_OK, srv);
1101         if (!ok)
1102                 return ok;
1103         if (cf2 != NULL)
1104         {
1105                 TLS_SAFE_F(cf2, sff | TLS_UNR(TLS_I_CERT_UNR, req),
1106                            bitset(TLS_I_CERT_EX, req),
1107                            bitset(TLS_S_CERT2_EX, status), TLS_S_CERT2_OK, srv);
1108         }
1109         if (kf2 != NULL)
1110         {
1111                 TLS_SAFE_F(kf2, sff | TLS_KEYSFF(req),
1112                            bitset(TLS_I_KEY_EX, req),
1113                            bitset(TLS_S_KEY2_EX, status), TLS_S_KEY2_OK, srv);
1114         }
1115
1116         /* create a method and a new context */
1117         if ((*ctx = SSL_CTX_new(srv ? SSLv23_server_method() :
1118                                       SSLv23_client_method())) == NULL)
1119         {
1120                 if (LogLevel > 7)
1121                         sm_syslog(LOG_WARNING, NOQID,
1122                                   "STARTTLS=%s, error: SSL_CTX_new(SSLv23_%s_method()) failed",
1123                                   who, who);
1124                 tlslogerr(LOG_WARNING, 9, who);
1125                 return false;
1126         }
1127
1128 # if _FFR_VRFY_TRUSTED_FIRST
1129         if (!tTd(88, 101))
1130         {
1131                 X509_STORE *store;
1132
1133                 /* get a pointer to the current certificate validation store */
1134                 store = SSL_CTX_get_cert_store(*ctx);   /* does not fail */
1135                 SM_ASSERT(store != NULL);
1136                 X509_STORE_set_flags(store, X509_V_FLAG_TRUSTED_FIRST);
1137         }
1138 # endif
1139
1140         if (CRLFile != NULL && !load_crlfile(*ctx, srv, CRLFile))
1141                 return false;
1142         if (CRLPath != NULL && !load_crlpath(*ctx, srv, CRLPath))
1143                 return false;
1144
1145 # if defined(SSL_MODE_AUTO_RETRY) && OPENSSL_VERSION_NUMBER >= 0x10100000L && OPENSSL_VERSION_NUMBER < 0x20000000L
1146         /*
1147          *  Turn off blocking I/O handling in OpenSSL: someone turned
1148          *  this on by default in 1.1? should we check first?
1149          */
1150 #  if _FFR_TESTS
1151         if (LogLevel > 9) {
1152                 sff = SSL_CTX_get_mode(*ctx);
1153                 if (sff & SSL_MODE_AUTO_RETRY)
1154                         sm_syslog(LOG_WARNING, NOQID,
1155                                 "STARTTLS=%s, SSL_MODE_AUTO_RETRY=set, mode=%#lx",
1156                                 who, sff);
1157         }
1158
1159         /* hack for testing! */
1160         if (tTd(96, 101) || getenv("SSL_MODE_AUTO_RETRY") != NULL)
1161                         SSL_CTX_set_mode(*ctx, SSL_MODE_AUTO_RETRY);
1162         else
1163 #  endif
1164         SSL_CTX_clear_mode(*ctx, SSL_MODE_AUTO_RETRY);
1165 # endif /* defined(SSL_MODE_AUTO_RETRY) && OPENSSL_VERSION_NUMBER >= 0x10100000L && OPENSSL_VERSION_NUMBER < 0x20000000L */
1166
1167
1168 # if TLS_NO_RSA
1169         /* turn off backward compatibility, required for no-rsa */
1170         SSL_CTX_set_options(*ctx, SSL_OP_NO_SSLv2);
1171 # endif
1172
1173
1174 # if !TLS_NO_RSA && MTA_RSA_TMP_CB
1175         /*
1176         **  Create a temporary RSA key
1177         **  XXX  Maybe we shouldn't create this always (even though it
1178         **  is only at startup).
1179         **  It is a time-consuming operation and it is not always necessary.
1180         **  maybe we should do it only on demand...
1181         */
1182
1183         if (bitset(TLS_I_RSA_TMP, req)
1184 #  if SM_CONF_SHM
1185             && ShmId != SM_SHM_NO_ID &&
1186             (rsa_tmp = RSA_generate_key(RSA_KEYLENGTH, RSA_F4, NULL,
1187                                         NULL)) == NULL
1188 #  else /* SM_CONF_SHM */
1189             && 0        /* no shared memory: no need to generate key now */
1190 #  endif /* SM_CONF_SHM */
1191            )
1192         {
1193                 if (LogLevel > 7)
1194                 {
1195                         sm_syslog(LOG_WARNING, NOQID,
1196                                   "STARTTLS=%s, error: RSA_generate_key failed",
1197                                   who);
1198                         tlslogerr(LOG_WARNING, 9, who);
1199                 }
1200                 return false;
1201         }
1202 # endif /* !TLS_NO_RSA && MTA_RSA_TMP_CB */
1203
1204         /*
1205         **  load private key
1206         **  XXX change this for DSA-only version
1207         */
1208
1209         if (bitset(TLS_S_KEY_OK, status) &&
1210             SSL_CTX_use_PrivateKey_file(*ctx, keyfile,
1211                                          SSL_FILETYPE_PEM) <= 0)
1212         {
1213                 if (LogLevel > 7)
1214                 {
1215                         sm_syslog(LOG_WARNING, NOQID,
1216                                   "STARTTLS=%s, error: SSL_CTX_use_PrivateKey_file(%s) failed",
1217                                   who, keyfile);
1218                         tlslogerr(LOG_WARNING, 9, who);
1219                 }
1220                 if (bitset(TLS_I_USE_KEY, req))
1221                         return false;
1222         }
1223
1224 # if _FFR_TLS_USE_CERTIFICATE_CHAIN_FILE
1225 #  define SSL_CTX_use_cert(ssl_ctx, certfile) \
1226         SSL_CTX_use_certificate_chain_file(ssl_ctx, certfile)
1227 #  define SSL_CTX_USE_CERT "SSL_CTX_use_certificate_chain_file"
1228 # else
1229 #  define SSL_CTX_use_cert(ssl_ctx, certfile) \
1230         SSL_CTX_use_certificate_file(ssl_ctx, certfile, SSL_FILETYPE_PEM)
1231 #  define SSL_CTX_USE_CERT "SSL_CTX_use_certificate_file"
1232 # endif
1233
1234         /* get the certificate file */
1235         if (bitset(TLS_S_CERT_OK, status) &&
1236             SSL_CTX_use_cert(*ctx, certfile) <= 0)
1237         {
1238                 if (LogLevel > 7)
1239                 {
1240                         sm_syslog(LOG_WARNING, NOQID,
1241                                   "STARTTLS=%s, error: %s(%s) failed",
1242                                   who, SSL_CTX_USE_CERT, certfile);
1243                         tlslogerr(LOG_WARNING, 9, who);
1244                 }
1245                 if (bitset(TLS_I_USE_CERT, req))
1246                         return false;
1247         }
1248
1249         /* check the private key */
1250         if (bitset(TLS_S_KEY_OK, status) &&
1251             (r = SSL_CTX_check_private_key(*ctx)) <= 0)
1252         {
1253                 /* Private key does not match the certificate public key */
1254                 if (LogLevel > 5)
1255                 {
1256                         sm_syslog(LOG_WARNING, NOQID,
1257                                   "STARTTLS=%s, error: SSL_CTX_check_private_key failed(%s): %d",
1258                                   who, keyfile, r);
1259                         tlslogerr(LOG_WARNING, 9, who);
1260                 }
1261                 if (bitset(TLS_I_USE_KEY, req))
1262                         return false;
1263         }
1264
1265         /* XXX this code is pretty much duplicated from above! */
1266
1267         /* load private key */
1268         if (bitset(TLS_S_KEY2_OK, status) &&
1269             SSL_CTX_use_PrivateKey_file(*ctx, kf2, SSL_FILETYPE_PEM) <= 0)
1270         {
1271                 if (LogLevel > 7)
1272                 {
1273                         sm_syslog(LOG_WARNING, NOQID,
1274                                   "STARTTLS=%s, error: SSL_CTX_use_PrivateKey_file(%s) failed",
1275                                   who, kf2);
1276                         tlslogerr(LOG_WARNING, 9, who);
1277                 }
1278         }
1279
1280         /* get the certificate file */
1281         if (bitset(TLS_S_CERT2_OK, status) &&
1282             SSL_CTX_use_cert(*ctx, cf2) <= 0)
1283         {
1284                 if (LogLevel > 7)
1285                 {
1286                         sm_syslog(LOG_WARNING, NOQID,
1287                                   "STARTTLS=%s, error: %s(%s) failed",
1288                                   who, SSL_CTX_USE_CERT, cf2);
1289                         tlslogerr(LOG_WARNING, 9, who);
1290                 }
1291         }
1292
1293         /* also check the private key */
1294         if (bitset(TLS_S_KEY2_OK, status) &&
1295             (r = SSL_CTX_check_private_key(*ctx)) <= 0)
1296         {
1297                 /* Private key does not match the certificate public key */
1298                 if (LogLevel > 5)
1299                 {
1300                         sm_syslog(LOG_WARNING, NOQID,
1301                                   "STARTTLS=%s, error: SSL_CTX_check_private_key 2 failed: %d",
1302                                   who, r);
1303                         tlslogerr(LOG_WARNING, 9, who);
1304                 }
1305         }
1306
1307         /* SSL_CTX_set_quiet_shutdown(*ctx, 1); violation of standard? */
1308
1309 # if SM_SSL_OP_TLS_BLOCK_PADDING_BUG
1310
1311         /*
1312         **  In OpenSSL 0.9.8[ab], enabling zlib compression breaks the
1313         **  padding bug work-around, leading to false positives and
1314         **  failed connections. We may not interoperate with systems
1315         **  with the bug, but this is better than breaking on all 0.9.8[ab]
1316         **  systems that have zlib support enabled.
1317         **  Note: this checks the runtime version of the library, not
1318         **  just the compile time version.
1319         */
1320
1321         rt_version = TLS_version_num();
1322         if (rt_version >= 0x00908000L && rt_version <= 0x0090802fL)
1323         {
1324                 comp_methods = SSL_COMP_get_compression_methods();
1325                 if (comp_methods != NULL && sk_SSL_COMP_num(comp_methods) > 0)
1326                         options &= ~SSL_OP_TLS_BLOCK_PADDING_BUG;
1327         }
1328 # endif
1329         SSL_CTX_set_options(*ctx, (long) options);
1330
1331 # if !NO_DH
1332         /* Diffie-Hellman initialization */
1333         if (bitset(TLS_I_TRY_DH, req))
1334         {
1335 #  if TLS_EC == 1
1336                 EC_KEY *ecdh;
1337 #  endif
1338
1339                 if (tTd(96, 8))
1340                         sm_dprintf("inittls: req=%#lx, status=%#lx\n",
1341                                 req, status);
1342                 if (bitset(TLS_S_DHPAR_OK, status))
1343                 {
1344                         BIO *bio;
1345
1346                         if ((bio = BIO_new_file(dhparam, "r")) != NULL)
1347                         {
1348                                 dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL);
1349                                 BIO_free(bio);
1350                                 if (dh == NULL && LogLevel > 7)
1351                                 {
1352                                         unsigned long err;
1353
1354                                         err = ERR_get_error();
1355                                         sm_syslog(LOG_WARNING, NOQID,
1356                                                   "STARTTLS=%s, error: cannot read DH parameters(%s): %s",
1357                                                   who, dhparam,
1358                                                   ERR_error_string(err, NULL));
1359                                         tlslogerr(LOG_WARNING, 9, who);
1360                                         SET_DH_DFL;
1361                                 }
1362                         }
1363                         else
1364                         {
1365                                 if (LogLevel > 5)
1366                                 {
1367                                         sm_syslog(LOG_WARNING, NOQID,
1368                                                   "STARTTLS=%s, error: BIO_new_file(%s) failed",
1369                                                   who, dhparam);
1370                                         tlslogerr(LOG_WARNING, 9, who);
1371                                 }
1372                         }
1373                 }
1374                 if (dh == NULL && bitset(TLS_I_DH1024|TLS_I_DH2048, req))
1375                 {
1376                         int bits;
1377                         DSA *dsa;
1378
1379                         bits = bitset(TLS_I_DH2048, req) ? 2048 : 1024;
1380                         if (tTd(96, 2))
1381                                 sm_dprintf("inittls: Generating %d bit DH parameters\n", bits);
1382
1383 #  if MTA_HAVE_DSA_GENERATE_EX
1384                         dsa = DSA_new();
1385                         if (dsa != NULL)
1386                         {
1387                                 r = DSA_generate_parameters_ex(dsa, bits, NULL,
1388                                                         0, NULL, NULL, NULL);
1389                                 if (r != 0)
1390                                         dh = DSA_dup_DH(dsa);
1391                         }
1392 #  else
1393                         /* this takes a while! */
1394                         dsa = DSA_generate_parameters(bits, NULL, 0, NULL,
1395                                                       NULL, 0, NULL);
1396                         dh = DSA_dup_DH(dsa);
1397 #  endif
1398                         DSA_free(dsa);
1399                 }
1400                 else if (dh == NULL && bitset(TLS_I_DHFIXED, req))
1401                 {
1402                         if (tTd(96, 2))
1403                                 sm_dprintf("inittls: Using precomputed 2048 bit DH parameters\n");
1404                         dh = get_dh2048();
1405                 }
1406                 else if (dh == NULL && bitset(TLS_I_DH512, req))
1407                 {
1408                         if (tTd(96, 2))
1409                                 sm_dprintf("inittls: Using precomputed 512 bit DH parameters\n");
1410                         dh = get_dh512();
1411                 }
1412
1413                 if (dh == NULL)
1414                 {
1415                         if (LogLevel > 9)
1416                         {
1417                                 unsigned long err;
1418
1419                                 err = ERR_get_error();
1420                                 sm_syslog(LOG_WARNING, NOQID,
1421                                           "STARTTLS=%s, error: cannot read or set DH parameters(%s): %s",
1422                                           who, dhparam,
1423                                           ERR_error_string(err, NULL));
1424                         }
1425                         if (bitset(TLS_I_REQ_DH, req))
1426                                 return false;
1427                 }
1428                 else
1429                 {
1430                         /* important to avoid small subgroup attacks */
1431                         SSL_CTX_set_options(*ctx, SSL_OP_SINGLE_DH_USE);
1432
1433                         SSL_CTX_set_tmp_dh(*ctx, dh);
1434                         if (LogLevel > 13)
1435                                 sm_syslog(LOG_INFO, NOQID,
1436                                           "STARTTLS=%s, Diffie-Hellman init, key=%d bit (%c)",
1437                                           who, 8 * DH_size(dh), *dhparam);
1438                         DH_free(dh);
1439                 }
1440
1441 #  if TLS_EC == 2
1442                 SSL_CTX_set_options(*ctx, SSL_OP_SINGLE_ECDH_USE);
1443                 SSL_CTX_set_ecdh_auto(*ctx, 1);
1444 #  elif TLS_EC == 1
1445                 ecdh = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1);
1446                 if (ecdh != NULL)
1447                 {
1448                         SSL_CTX_set_options(*ctx, SSL_OP_SINGLE_ECDH_USE);
1449                         SSL_CTX_set_tmp_ecdh(*ctx, ecdh);
1450                         EC_KEY_free(ecdh);
1451                 }
1452                 else if (LogLevel > 9)
1453                 {
1454                         sm_syslog(LOG_WARNING, NOQID,
1455                                   "STARTTLS=%s, EC_KEY_new_by_curve_name(NID_X9_62_prime256v1)=failed, error=%s",
1456                                   who, ERR_error_string(ERR_get_error(), NULL));
1457                 }
1458 #  endif /* TLS_EC */
1459
1460         }
1461 # endif /* !NO_DH */
1462
1463
1464         /* XXX do we need this cache here? */
1465         if (bitset(TLS_I_CACHE, req))
1466         {
1467                 SSL_CTX_sess_set_cache_size(*ctx, 1);
1468                 SSL_CTX_set_timeout(*ctx, 1);
1469                 SSL_CTX_set_session_id_context(*ctx,
1470                         (void *) &server_session_id_context,
1471                         sizeof(server_session_id_context));
1472                 (void) SSL_CTX_set_session_cache_mode(*ctx,
1473                                 SSL_SESS_CACHE_SERVER);
1474         }
1475         else
1476         {
1477                 (void) SSL_CTX_set_session_cache_mode(*ctx,
1478                                 SSL_SESS_CACHE_OFF);
1479         }
1480
1481         /* load certificate locations and default CA paths */
1482         if (bitset(TLS_S_CERTP_EX, status) && bitset(TLS_S_CERTF_EX, status))
1483         {
1484                 if ((r = SSL_CTX_load_verify_locations(*ctx, cacertfile,
1485                                                        cacertpath)) == 1)
1486                 {
1487 # if !TLS_NO_RSA && MTA_RSA_TMP_CB
1488                         if (bitset(TLS_I_RSA_TMP, req))
1489                                 SSL_CTX_set_tmp_rsa_callback(*ctx, tmp_rsa_key);
1490 # endif
1491
1492                         /*
1493                         **  We have to install our own verify callback:
1494                         **  SSL_VERIFY_PEER requests a client cert but even
1495                         **  though *FAIL_IF* isn't set, the connection
1496                         **  will be aborted if the client presents a cert
1497                         **  that is not "liked" (can't be verified?) by
1498                         **  the TLS library :-(
1499                         */
1500
1501                         /*
1502                         **  XXX currently we could call tls_set_verify()
1503                         **  but we hope that that function will later on
1504                         **  only set the mode per connection.
1505                         */
1506
1507                         SSL_CTX_set_verify(*ctx,
1508                                 bitset(TLS_I_NO_VRFY, req) ? SSL_VERIFY_NONE
1509                                                            : SSL_VERIFY_PEER,
1510                                 NULL);
1511
1512                         if (srv)
1513                         {
1514                                 SSL_CTX_set_client_CA_list(*ctx,
1515                                         SSL_load_client_CA_file(cacertfile));
1516                         }
1517                         SSL_CTX_set_cert_verify_callback(*ctx, tls_verify_cb,
1518                                                         NULL);
1519                 }
1520                 else
1521                 {
1522                         /*
1523                         **  can't load CA data; do we care?
1524                         **  the data is necessary to authenticate the client,
1525                         **  which in turn would be necessary
1526                         **  if we want to allow relaying based on it.
1527                         */
1528
1529                         if (LogLevel > 5)
1530                         {
1531                                 sm_syslog(LOG_WARNING, NOQID,
1532                                           "STARTTLS=%s, error: load verify locs %s, %s failed: %d",
1533                                           who, cacertpath, cacertfile, r);
1534                                 tlslogerr(LOG_WARNING,
1535                                         bitset(TLS_I_VRFY_LOC, req) ? 8 : 9,
1536                                         who);
1537                         }
1538                         if (bitset(TLS_I_VRFY_LOC, req))
1539                                 return false;
1540                 }
1541         }
1542
1543         /* XXX: make this dependent on an option? */
1544         if (tTd(96, 9))
1545                 SSL_CTX_set_info_callback(*ctx, apps_ssl_info_cb);
1546
1547         /* install our own cipher list */
1548         if (CipherList != NULL && *CipherList != '\0')
1549         {
1550                 if (SSL_CTX_set_cipher_list(*ctx, CipherList) <= 0)
1551                 {
1552                         if (LogLevel > 7)
1553                         {
1554                                 sm_syslog(LOG_WARNING, NOQID,
1555                                           "STARTTLS=%s, error: SSL_CTX_set_cipher_list(%s) failed, list ignored",
1556                                           who, CipherList);
1557
1558                                 tlslogerr(LOG_WARNING, 9, who);
1559                         }
1560                         /* failure if setting to this list is required? */
1561                 }
1562         }
1563
1564         if (LogLevel > 12)
1565                 sm_syslog(LOG_INFO, NOQID, "STARTTLS=%s, init=%d", who, ok);
1566
1567 # if 0
1568         /*
1569         **  this label is required if we want to have a "clean" exit
1570         **  see the comments above at the initialization of cf2
1571         */
1572
1573     endinittls:
1574 # endif /* 0 */
1575
1576         /* undo damage to global variables */
1577         if (cf2 != NULL)
1578                 *--cf2 = ',';
1579         if (kf2 != NULL)
1580                 *--kf2 = ',';
1581
1582         return ok;
1583 }
1584
1585 /*
1586 **  CERT_FP -- get cert fingerprint
1587 **
1588 **      Parameters:
1589 **              cert -- TLS cert
1590 **              evp_digest -- digest algorithm
1591 **              mac -- macro storage
1592 **              macro -- where to store cert fp
1593 **
1594 **      Returns:
1595 **              <=0: cert fp calculation failed
1596 **              >0: cert fp calculation ok
1597 */
1598
1599 static int
1600 cert_fp(cert, evp_digest, mac, macro)
1601         X509 *cert;
1602         const EVP_MD *evp_digest;
1603         MACROS_T *mac;
1604         char *macro;
1605 {
1606         unsigned int n;
1607         int r;
1608         unsigned char md[EVP_MAX_MD_SIZE];
1609         char md5h[EVP_MAX_MD_SIZE * 3];
1610         static const char hexcodes[] = "0123456789ABCDEF";
1611
1612         n = 0;
1613         if (X509_digest(cert, EVP_digest, md, &n) == 0 || n <= 0)
1614         {
1615                 macdefine(mac, A_TEMP, macid(macro), "");
1616                 return 0;
1617         }
1618
1619         SM_ASSERT((n * 3) + 2 < sizeof(md5h));
1620         for (r = 0; r < (int) n; r++)
1621         {
1622                 md5h[r * 3] = hexcodes[(md[r] & 0xf0) >> 4];
1623                 md5h[(r * 3) + 1] = hexcodes[(md[r] & 0x0f)];
1624                 md5h[(r * 3) + 2] = ':';
1625         }
1626         md5h[(n * 3) - 1] = '\0';
1627         macdefine(mac, A_TEMP, macid(macro), md5h);
1628         return 1;
1629 }
1630
1631 /* host for logging */
1632 #define whichhost       host == NULL ? "local" : host
1633
1634 # if _FFR_TLS_ALTNAMES
1635
1636 /*
1637 **  CLEARCLASS -- clear the specified class (called from stabapply)
1638 **
1639 **      Parameters:
1640 **              s -- STAB
1641 **              id -- class id
1642 **
1643 **      Returns:
1644 **              none.
1645 */
1646
1647 static void
1648 clearclass(s, id)
1649         STAB *s;
1650         int id;
1651 {
1652         if (s->s_symtype != ST_CLASS)
1653                 return;
1654         if (bitnset(bitidx(id), s->s_class))
1655                 clrbitn(bitidx(id), s->s_class);
1656 }
1657
1658 /*
1659 **  GETALTNAMES -- set subject_alt_name
1660 **
1661 **      Parameters:
1662 **              cert -- cert
1663 **              srv -- server side?
1664 **              host -- hostname of other side
1665 **
1666 **      Returns:
1667 **              none.
1668 */
1669
1670 static void
1671 getaltnames(cert, srv, host)
1672         X509 *cert;
1673         bool srv;
1674         const char *host;
1675 {
1676         STACK_OF(GENERAL_NAME) *gens;
1677         int i, j, len, r;
1678         const GENERAL_NAME *gn;
1679         char *dnsname, *who;
1680
1681         if (!SetCertAltnames)
1682                 return;
1683         who = srv ? "server" : "client";
1684         gens = X509_get_ext_d2i(cert, NID_subject_alt_name, 0, 0);
1685         if (gens == NULL)
1686                 return;
1687
1688         r = sk_GENERAL_NAME_num(gens);
1689         for (i = 0; i < r; i++)
1690         {
1691                 gn = sk_GENERAL_NAME_value(gens, i);
1692                 if (gn == NULL || gn->type != GEN_DNS)
1693                         continue;
1694
1695                 /* Ensure data is IA5 */
1696                 if (ASN1_STRING_type(gn->d.ia5) != V_ASN1_IA5STRING)
1697                 {
1698                         if (LogLevel > 6)
1699                                 sm_syslog(LOG_INFO, NOQID,
1700                                         "STARTTLS=%s, relay=%.100s, field=AltName, status=value contains non IA5",
1701                                         who, whichhost);
1702                         continue;
1703                 }
1704                 dnsname = (char *) MTA_ASN1_STRING_data(gn->d.ia5);
1705                 if (dnsname == NULL)
1706                         continue;
1707                 len = ASN1_STRING_length(gn->d.ia5);
1708
1709                 /*
1710                 **  "remove" trailing NULs (except for one of course),
1711                 **  those can happen and are OK (not a sign of an attack)
1712                 */
1713
1714                 while (len > 0 && '\0' == dnsname[len - 1])
1715                         len--;
1716
1717 #define ISPRINT(c)      (isascii(c) && isprint(c))
1718
1719                 /* just check for printable char for now */
1720                 for (j = 0; j < len && ISPRINT(dnsname[j]); j++)
1721                         ;
1722                 if (dnsname[j] != '\0' || len != j)
1723                         continue;
1724
1725                 setclass(macid("{cert_altnames}"), xtextify(dnsname, "<>\")"));
1726                 if (LogLevel > 14)
1727                         sm_syslog(LOG_DEBUG, NOQID,
1728                                 "STARTTLS=%s, relay=%.100s, AltName=%s",
1729                                 who, whichhost, xtextify(dnsname, "<>\")"));
1730         }
1731 }
1732 # else
1733 #  define getaltnames(cert, srv, host)
1734 # endif /* _FFR_TLS_ALTNAMES */
1735
1736 /*
1737 **  TLS_GET_INFO -- get information about TLS connection
1738 **
1739 **      Parameters:
1740 **              ssl -- TLS session context
1741 **              srv -- server side?
1742 **              host -- hostname of other side
1743 **              mac -- macro storage
1744 **              certreq -- did we ask for a cert?
1745 **
1746 **      Returns:
1747 **              result of authentication.
1748 **
1749 **      Side Effects:
1750 **              sets various TLS related macros.
1751 */
1752
1753 int
1754 tls_get_info(ssl, srv, host, mac, certreq)
1755         SSL *ssl;
1756         bool srv;
1757         char *host;
1758         MACROS_T *mac;
1759         bool certreq;
1760 {
1761         const SSL_CIPHER *c;
1762         int b, r;
1763         long verifyok;
1764         char *s, *who;
1765         char bitstr[16];
1766         X509 *cert;
1767 # if DANE
1768         dane_vrfy_ctx_P dane_vrfy_ctx;
1769 # endif
1770
1771         c = SSL_get_current_cipher(ssl);
1772
1773         /* cast is just workaround for compiler warning */
1774         macdefine(mac, A_TEMP, macid("{cipher}"),
1775                   (char *) SSL_CIPHER_get_name(c));
1776         b = SSL_CIPHER_get_bits(c, &r);
1777         (void) sm_snprintf(bitstr, sizeof(bitstr), "%d", b);
1778         macdefine(mac, A_TEMP, macid("{cipher_bits}"), bitstr);
1779         (void) sm_snprintf(bitstr, sizeof(bitstr), "%d", r);
1780         macdefine(mac, A_TEMP, macid("{alg_bits}"), bitstr);
1781         s = (char *) SSL_get_version(ssl);
1782         if (s == NULL)
1783                 s = "UNKNOWN";
1784         macdefine(mac, A_TEMP, macid("{tls_version}"), s);
1785
1786         who = srv ? "server" : "client";
1787         cert = SSL_get_peer_certificate(ssl);
1788         verifyok = SSL_get_verify_result(ssl);
1789         if (LogLevel > 14)
1790                 sm_syslog(LOG_INFO, NOQID,
1791                           "STARTTLS=%s, get_verify: %ld get_peer: 0x%lx",
1792                           who, verifyok, (unsigned long) cert);
1793 # if _FFR_TLS_ALTNAMES
1794         stabapply(clearclass, macid("{cert_altnames}"));
1795 # endif
1796         if (cert != NULL)
1797         {
1798                 X509_NAME *subj, *issuer;
1799                 char buf[MAXNAME];
1800
1801                 subj = X509_get_subject_name(cert);
1802                 issuer = X509_get_issuer_name(cert);
1803                 X509_NAME_oneline(subj, buf, sizeof(buf));
1804                 macdefine(mac, A_TEMP, macid("{cert_subject}"),
1805                          xtextify(buf, "<>\")"));
1806                 X509_NAME_oneline(issuer, buf, sizeof(buf));
1807                 macdefine(mac, A_TEMP, macid("{cert_issuer}"),
1808                          xtextify(buf, "<>\")"));
1809
1810 #  define LL_BADCERT    8
1811
1812 #define CERTFPMACRO (CertFingerprintAlgorithm != NULL ? "{cert_fp}" : "{cert_md5}")
1813
1814 #define CHECK_X509_NAME(which)  \
1815         do {    \
1816                 if (r == -1)    \
1817                 {               \
1818                         sm_strlcpy(buf, "BadCertificateUnknown", sizeof(buf)); \
1819                         if (LogLevel > LL_BADCERT)      \
1820                                 sm_syslog(LOG_INFO, NOQID,      \
1821                                         "STARTTLS=%s, relay=%.100s, field=%s, status=failed to extract CN",     \
1822                                         who, whichhost, which); \
1823                 }               \
1824                 else if ((size_t)r >= sizeof(buf) - 1)  \
1825                 {               \
1826                         sm_strlcpy(buf, "BadCertificateTooLong", sizeof(buf)); \
1827                         if (LogLevel > 7)       \
1828                                 sm_syslog(LOG_INFO, NOQID,      \
1829                                         "STARTTLS=%s, relay=%.100s, field=%s, status=CN too long",      \
1830                                         who, whichhost, which); \
1831                 }               \
1832                 else if ((size_t)r > strlen(buf))       \
1833                 {               \
1834                         sm_strlcpy(buf, "BadCertificateContainsNUL",    \
1835                                 sizeof(buf));   \
1836                         if (LogLevel > 7)       \
1837                                 sm_syslog(LOG_INFO, NOQID,      \
1838                                         "STARTTLS=%s, relay=%.100s, field=%s, status=CN contains NUL",  \
1839                                         who, whichhost, which); \
1840                 }               \
1841         } while (0)
1842
1843                 r = X509_NAME_get_text_by_NID(subj, NID_commonName, buf,
1844                         sizeof buf);
1845                 CHECK_X509_NAME("cn_subject");
1846                 macdefine(mac, A_TEMP, macid("{cn_subject}"),
1847                          xtextify(buf, "<>\")"));
1848                 r = X509_NAME_get_text_by_NID(issuer, NID_commonName, buf,
1849                         sizeof buf);
1850                 CHECK_X509_NAME("cn_issuer");
1851                 macdefine(mac, A_TEMP, macid("{cn_issuer}"),
1852                          xtextify(buf, "<>\")"));
1853                 (void) cert_fp(cert, EVP_digest, mac, CERTFPMACRO);
1854                 getaltnames(cert, srv, host);
1855         }
1856         else
1857         {
1858                 macdefine(mac, A_PERM, macid("{cert_subject}"), "");
1859                 macdefine(mac, A_PERM, macid("{cert_issuer}"), "");
1860                 macdefine(mac, A_PERM, macid("{cn_subject}"), "");
1861                 macdefine(mac, A_PERM, macid("{cn_issuer}"), "");
1862                 macdefine(mac, A_TEMP, macid(CERTFPMACRO), "");
1863         }
1864 # if DANE
1865         dane_vrfy_ctx = NULL;
1866         if (TLSsslidx >= 0)
1867         {
1868                 tlsi_ctx_T *tlsi_ctx;
1869
1870                 tlsi_ctx = (tlsi_ctx_P) SSL_get_ex_data(ssl, TLSsslidx);
1871                 if (tlsi_ctx != NULL)
1872                         dane_vrfy_ctx = &(tlsi_ctx->tlsi_dvc);
1873         }
1874 #  define DANE_VRFY_RES_IS(r) \
1875         ((dane_vrfy_ctx != NULL) && dane_vrfy_ctx->dane_vrfy_res == (r))
1876         if (DANE_VRFY_RES_IS(DANE_VRFY_OK))
1877         {
1878                 s = "TRUSTED";
1879                 r = TLS_AUTH_OK;
1880         }
1881         else if (DANE_VRFY_RES_IS(DANE_VRFY_FAIL))
1882         {
1883                 s = "DANE_FAIL";
1884                 r = TLS_AUTH_FAIL;
1885         }
1886         else
1887 # endif /* if DANE */
1888         switch (verifyok)
1889         {
1890           case X509_V_OK:
1891                 if (cert != NULL)
1892                 {
1893                         s = "OK";
1894                         r = TLS_AUTH_OK;
1895                 }
1896                 else
1897                 {
1898                         s = certreq ? "NO" : "NOT",
1899                         r = TLS_AUTH_NO;
1900                 }
1901                 break;
1902           default:
1903                 s = "FAIL";
1904                 r = TLS_AUTH_FAIL;
1905                 break;
1906         }
1907         macdefine(mac, A_PERM, macid("{verify}"), s);
1908         if (cert != NULL)
1909                 X509_free(cert);
1910
1911         /* do some logging */
1912         if (LogLevel > 8)
1913         {
1914                 char *vers, *s1, *s2, *cbits, *algbits;
1915
1916                 vers = macget(mac, macid("{tls_version}"));
1917                 cbits = macget(mac, macid("{cipher_bits}"));
1918                 algbits = macget(mac, macid("{alg_bits}"));
1919                 s1 = macget(mac, macid("{verify}"));
1920                 s2 = macget(mac, macid("{cipher}"));
1921
1922 # if DANE
1923 #  define LOG_DANE_FP   \
1924         ('\0' != dane_vrfy_ctx->dane_vrfy_fp[0] && DANE_VRFY_RES_IS(DANE_VRFY_FAIL))
1925 # endif
1926                 /* XXX: maybe cut off ident info? */
1927                 sm_syslog(LOG_INFO, NOQID,
1928                           "STARTTLS=%s, relay=%.100s, version=%.16s, verify=%.16s, cipher=%.64s, bits=%.6s/%.6s%s%s",
1929                           who,
1930                           host == NULL ? "local" : host,
1931                           vers, s1, s2, /* sm_snprintf() can deal with NULL */
1932                           algbits == NULL ? "0" : algbits,
1933                           cbits == NULL ? "0" : cbits
1934 # if DANE
1935                         , LOG_DANE_FP ? ", pubkey_fp=" : ""
1936                         , LOG_DANE_FP ? dane_vrfy_ctx->dane_vrfy_fp : ""
1937 # else
1938                         , "", ""
1939 # endif
1940                         );
1941                 if (LogLevel > 11)
1942                 {
1943                         /*
1944                         **  Maybe run xuntextify on the strings?
1945                         **  That is easier to read but makes it maybe a bit
1946                         **  more complicated to figure out the right values
1947                         **  for the access map...
1948                         */
1949
1950                         s1 = macget(mac, macid("{cert_subject}"));
1951                         s2 = macget(mac, macid("{cert_issuer}"));
1952                         sm_syslog(LOG_INFO, NOQID,
1953                                   "STARTTLS=%s, cert-subject=%.256s, cert-issuer=%.256s, verifymsg=%s",
1954                                   who, s1, s2,
1955                                   X509_verify_cert_error_string(verifyok));
1956                 }
1957         }
1958         return r;
1959 }
1960
1961 /*
1962 **  ENDTLS -- shutdown secure connection
1963 **
1964 **      Parameters:
1965 **              pssl -- pointer to TLS session context
1966 **              who -- server/client (for logging).
1967 **
1968 **      Returns:
1969 **              success? (EX_* code)
1970 */
1971
1972 int
1973 endtls(pssl, who)
1974         SSL **pssl;
1975         const char *who;
1976 {
1977         SSL *ssl;
1978         int ret, r;
1979
1980         SM_REQUIRE(pssl != NULL);
1981         ret = EX_OK;
1982         ssl = *pssl;
1983         if (ssl == NULL)
1984                 return ret;
1985
1986         if ((r = SSL_shutdown(ssl)) < 0)
1987         {
1988                 if (LogLevel > 11)
1989                 {
1990                         sm_syslog(LOG_WARNING, NOQID,
1991                                   "STARTTLS=%s, SSL_shutdown failed: %d",
1992                                   who, r);
1993                         tlslogerr(LOG_WARNING, 11, who);
1994                 }
1995                 ret = EX_SOFTWARE;
1996         }
1997
1998         /*
1999         **  Bug in OpenSSL (at least up to 0.9.6b):
2000         **  From: Lutz.Jaenicke@aet.TU-Cottbus.DE
2001         **  Message-ID: <20010723152244.A13122@serv01.aet.tu-cottbus.de>
2002         **  To: openssl-users@openssl.org
2003         **  Subject: Re: SSL_shutdown() woes (fwd)
2004         **
2005         **  The side sending the shutdown alert first will
2006         **  not care about the answer of the peer but will
2007         **  immediately return with a return value of "0"
2008         **  (ssl/s3_lib.c:ssl3_shutdown()). SSL_get_error will evaluate
2009         **  the value of "0" and as the shutdown alert of the peer was
2010         **  not received (actually, the program did not even wait for
2011         **  the answer), an SSL_ERROR_SYSCALL is flagged, because this
2012         **  is the default rule in case everything else does not apply.
2013         **
2014         **  For your server the problem is different, because it
2015         **  receives the shutdown first (setting SSL_RECEIVED_SHUTDOWN),
2016         **  then sends its response (SSL_SENT_SHUTDOWN), so for the
2017         **  server the shutdown was successful.
2018         **
2019         **  As is by know, you would have to call SSL_shutdown() once
2020         **  and ignore an SSL_ERROR_SYSCALL returned. Then call
2021         **  SSL_shutdown() again to actually get the server's response.
2022         **
2023         **  In the last discussion, Bodo Moeller concluded that a
2024         **  rewrite of the shutdown code would be necessary, but
2025         **  probably with another API, as the change would not be
2026         **  compatible to the way it is now.  Things do not become
2027         **  easier as other programs do not follow the shutdown
2028         **  guidelines anyway, so that a lot error conditions and
2029         **  compitibility issues would have to be caught.
2030         **
2031         **  For now the recommondation is to ignore the error message.
2032         */
2033
2034         else if (r == 0)
2035         {
2036                 if (LogLevel > 15)
2037                 {
2038                         sm_syslog(LOG_WARNING, NOQID,
2039                                   "STARTTLS=%s, SSL_shutdown not done",
2040                                   who);
2041                         tlslogerr(LOG_WARNING, 15, who);
2042                 }
2043                 ret = EX_SOFTWARE;
2044         }
2045         SM_SSL_FREE(*pssl);
2046         return ret;
2047 }
2048
2049 # if !TLS_NO_RSA && MTA_RSA_TMP_CB
2050 /*
2051 **  TMP_RSA_KEY -- return temporary RSA key
2052 **
2053 **      Parameters:
2054 **              ssl -- TLS session context
2055 **              export --
2056 **              keylength --
2057 **
2058 **      Returns:
2059 **              temporary RSA key.
2060 */
2061
2062 #  ifndef MAX_RSA_TMP_CNT
2063 #   define MAX_RSA_TMP_CNT      1000    /* XXX better value? */
2064 #  endif
2065
2066 /* ARGUSED0 */
2067 static RSA *
2068 tmp_rsa_key(s, export, keylength)
2069         SSL *s;
2070         int export;
2071         int keylength;
2072 {
2073 #  if SM_CONF_SHM
2074         extern int ShmId;
2075         extern int *PRSATmpCnt;
2076
2077         if (ShmId != SM_SHM_NO_ID && rsa_tmp != NULL &&
2078             ++(*PRSATmpCnt) < MAX_RSA_TMP_CNT)
2079                 return rsa_tmp;
2080 #  endif /* SM_CONF_SHM */
2081
2082         if (rsa_tmp != NULL)
2083                 RSA_free(rsa_tmp);
2084         rsa_tmp = RSA_generate_key(RSA_KEYLENGTH, RSA_F4, NULL, NULL);
2085         if (rsa_tmp == NULL)
2086         {
2087                 if (LogLevel > 0)
2088                         sm_syslog(LOG_ERR, NOQID,
2089                                   "STARTTLS=server, tmp_rsa_key: RSA_generate_key failed!");
2090         }
2091         else
2092         {
2093 #  if SM_CONF_SHM
2094 #   if 0
2095                 /*
2096                 **  XXX we can't (yet) share the new key...
2097                 **      The RSA structure contains pointers hence it can't be
2098                 **      easily kept in shared memory.  It must be transformed
2099                 **      into a continuous memory region first, then stored,
2100                 **      and later read out again (each time re-transformed).
2101                 */
2102
2103                 if (ShmId != SM_SHM_NO_ID)
2104                         *PRSATmpCnt = 0;
2105 #   endif /* 0 */
2106 #  endif /* SM_CONF_SHM */
2107                 if (LogLevel > 9)
2108                         sm_syslog(LOG_ERR, NOQID,
2109                                   "STARTTLS=server, tmp_rsa_key: new temp RSA key");
2110         }
2111         return rsa_tmp;
2112 }
2113 # endif /* !TLS_NO_RSA && MTA_RSA_TMP_CB */
2114
2115 /*
2116 **  APPS_SSL_INFO_CB -- info callback for TLS connections
2117 **
2118 **      Parameters:
2119 **              ssl -- TLS session context
2120 **              where -- state in handshake
2121 **              ret -- return code of last operation
2122 **
2123 **      Returns:
2124 **              none.
2125 */
2126
2127 static void
2128 apps_ssl_info_cb(ssl, where, ret)
2129         const SSL *ssl;
2130         int where;
2131         int ret;
2132 {
2133         int w;
2134         char *str;
2135         BIO *bio_err = NULL;
2136
2137         if (LogLevel > 14)
2138                 sm_syslog(LOG_INFO, NOQID,
2139                           "STARTTLS: info_callback where=0x%x, ret=%d",
2140                           where, ret);
2141
2142         w = where & ~SSL_ST_MASK;
2143         if (bio_err == NULL)
2144                 bio_err = BIO_new_fp(stderr, BIO_NOCLOSE);
2145
2146         if (bitset(SSL_ST_CONNECT, w))
2147                 str = "SSL_connect";
2148         else if (bitset(SSL_ST_ACCEPT, w))
2149                 str = "SSL_accept";
2150         else
2151                 str = "undefined";
2152
2153         if (bitset(SSL_CB_LOOP, where))
2154         {
2155                 if (LogLevel > 12)
2156                         sm_syslog(LOG_NOTICE, NOQID,
2157                                 "STARTTLS: %s:%s",
2158                                 str, SSL_state_string_long(ssl));
2159         }
2160         else if (bitset(SSL_CB_ALERT, where))
2161         {
2162                 str = bitset(SSL_CB_READ, where) ? "read" : "write";
2163                 if (LogLevel > 12)
2164                         sm_syslog(LOG_NOTICE, NOQID,
2165                                 "STARTTLS: SSL3 alert %s:%s:%s",
2166                                 str, SSL_alert_type_string_long(ret),
2167                                 SSL_alert_desc_string_long(ret));
2168         }
2169         else if (bitset(SSL_CB_EXIT, where))
2170         {
2171                 if (ret == 0)
2172                 {
2173                         if (LogLevel > 7)
2174                                 sm_syslog(LOG_WARNING, NOQID,
2175                                         "STARTTLS: %s:failed in %s",
2176                                         str, SSL_state_string_long(ssl));
2177                 }
2178                 else if (ret < 0)
2179                 {
2180                         if (LogLevel > 7)
2181                                 sm_syslog(LOG_WARNING, NOQID,
2182                                         "STARTTLS: %s:error in %s",
2183                                         str, SSL_state_string_long(ssl));
2184                 }
2185         }
2186 }
2187
2188 /*
2189 **  TLS_VERIFY_LOG -- log verify error for TLS certificates
2190 **
2191 **      Parameters:
2192 **              ok -- verify ok?
2193 **              ctx -- X509 context
2194 **              name -- from where is this called?
2195 **
2196 **      Returns:
2197 **              1 -- ok
2198 */
2199
2200 static int
2201 tls_verify_log(ok, ctx, name)
2202         int ok;
2203         X509_STORE_CTX *ctx;
2204         const char *name;
2205 {
2206         X509 *cert;
2207         int reason, depth;
2208         char buf[512];
2209
2210         cert = X509_STORE_CTX_get_current_cert(ctx);
2211         reason = X509_STORE_CTX_get_error(ctx);
2212         depth = X509_STORE_CTX_get_error_depth(ctx);
2213         X509_NAME_oneline(X509_get_subject_name(cert), buf, sizeof(buf));
2214         sm_syslog(LOG_INFO, NOQID,
2215                   "STARTTLS: %s cert verify: depth=%d %s, state=%d, reason=%s",
2216                   name, depth, buf, ok, X509_verify_cert_error_string(reason));
2217         return 1;
2218 }
2219
2220 /*
2221 **  Declaration and access to tlsi_ctx in callbacks.
2222 **  Currently only used in one of them.
2223 */
2224
2225 #define SM_DECTLSI      \
2226         tlsi_ctx_T *tlsi_ctx;   \
2227         SSL *ssl
2228 #define SM_GETTLSI      \
2229         do {            \
2230                 tlsi_ctx = NULL;        \
2231                 if (TLSsslidx >= 0)     \
2232                 {       \
2233                         ssl = (SSL *) X509_STORE_CTX_get_ex_data(ctx,   \
2234                                 SSL_get_ex_data_X509_STORE_CTX_idx());  \
2235                         if (ssl != NULL)        \
2236                                 tlsi_ctx = (tlsi_ctx_P) SSL_get_ex_data(ssl, TLSsslidx);        \
2237                 }       \
2238         }       \
2239         while (0)
2240
2241
2242 # if DANE
2243
2244 /*
2245 **  DANE_GET_TLSA -- Retrieve TLSA RR for DANE
2246 **
2247 **      Parameters:
2248 **              dane -- dane verify context
2249 **
2250 **      Returns:
2251 **              dane_tlsa if TLSA RR is available
2252 **              NULL otherwise
2253 */
2254
2255 dane_tlsa_P
2256 dane_get_tlsa(dane_vrfy_ctx)
2257         dane_vrfy_ctx_P dane_vrfy_ctx;
2258 {
2259         STAB *s;
2260         dane_tlsa_P dane_tlsa;
2261
2262         dane_tlsa = NULL;
2263         if (NULL == dane_vrfy_ctx)
2264                 return NULL;
2265         if (dane_vrfy_ctx->dane_vrfy_chk == DANE_NEVER ||
2266             dane_vrfy_ctx->dane_vrfy_host == NULL)
2267                 return NULL;
2268
2269         GETTLSANOX(dane_vrfy_ctx->dane_vrfy_host, &s,
2270                 dane_vrfy_ctx->dane_vrfy_port);
2271         if (NULL == s)
2272                 goto notfound;
2273         dane_tlsa = s->s_tlsa;
2274         if (NULL == dane_tlsa)
2275                 goto notfound;
2276         if (0 == dane_tlsa->dane_tlsa_n)
2277                 goto notfound;
2278         if (tTd(96, 4))
2279                 sm_dprintf("dane_get_tlsa, chk=%d, host=%s, n=%d, stat=entry found\n",
2280                         dane_vrfy_ctx->dane_vrfy_chk,
2281                         dane_vrfy_ctx->dane_vrfy_host, dane_tlsa->dane_tlsa_n);
2282         return dane_tlsa;
2283
2284   notfound:
2285         if (tTd(96, 4))
2286                 sm_dprintf("dane_get_tlsa, chk=%d, host=%s, stat=no valid entry found\n",
2287                         dane_vrfy_ctx->dane_vrfy_chk,
2288                         dane_vrfy_ctx->dane_vrfy_host);
2289         return NULL;
2290 }
2291
2292 /*
2293 **  DANE_VERIFY -- verify callback for TLS certificates
2294 **
2295 **      Parameters:
2296 **              ctx -- X509 context
2297 **              dane_vrfy_ctx -- callback context
2298 **
2299 **      Returns:
2300 **              DANE_VRFY_{OK,NONE,FAIL}
2301 */
2302
2303 /* NOTE: this only works because the "matching type" is 0, 1, 2 for these! */
2304 static const char *dane_mdalgs[] = { "", "sha256", "sha512" };
2305
2306 static int
2307 dane_verify(ctx, dane_vrfy_ctx)
2308         X509_STORE_CTX *ctx;
2309         dane_vrfy_ctx_P dane_vrfy_ctx;
2310 {
2311         int r, i, ok, mdalg;
2312         X509 *cert;
2313         dane_tlsa_P dane_tlsa;
2314         char *fp;
2315
2316         dane_tlsa = dane_get_tlsa(dane_vrfy_ctx);
2317         if (dane_tlsa == NULL)
2318                 return DANE_VRFY_NONE;
2319
2320         dane_vrfy_ctx->dane_vrfy_fp[0] = '\0';
2321         cert = X509_STORE_CTX_get0_cert(ctx);
2322         if (tTd(96, 8))
2323                 sm_dprintf("dane_verify, cert=%p\n", (void *)cert);
2324         if (cert == NULL)
2325                 return DANE_VRFY_FAIL;
2326
2327         ok = DANE_VRFY_NONE;
2328         fp = NULL;
2329
2330         /*
2331         **  If the TLSA RRs would be sorted the two loops below could
2332         **  be merged into one and simply change mdalg when it changes
2333         **  in dane_tlsa->dane_tlsa_rr.
2334         */
2335
2336         /* use a different order? */
2337         for (mdalg = 0; mdalg < SM_ARRAY_SIZE(dane_mdalgs); mdalg++)
2338         {
2339                 SM_FREE(fp);
2340                 r = 0;
2341                 for (i = 0; i < dane_tlsa->dane_tlsa_n; i++)
2342                 {
2343                         char *p;
2344                         int alg;
2345
2346                         p = dane_tlsa->dane_tlsa_rr[i];
2347
2348                         /* ignore bogus/unsupported TLSA RRs */
2349                         alg = dane_tlsa_chk(p, dane_tlsa->dane_tlsa_len[i],
2350                                           dane_vrfy_ctx->dane_vrfy_host, false);
2351                         if (tTd(96, 8))
2352                                 sm_dprintf("dane_verify, alg=%d, mdalg=%d\n",
2353                                         alg, mdalg);
2354                         if (alg != mdalg)
2355                                 continue;
2356
2357                         if (NULL == fp)
2358                         {
2359                                 r = pubkey_fp(cert, dane_mdalgs[mdalg], &fp);
2360                                 if (NULL == fp)
2361                                         return DANE_VRFY_FAIL;
2362                                         /* or continue? */
2363                         }
2364
2365                         /* just for logging */
2366                         if (r > 0 && fp != NULL)
2367                         {
2368                                 (void) data2hex((unsigned char *)fp, r,
2369                                         (unsigned char *)dane_vrfy_ctx->dane_vrfy_fp,
2370                                         sizeof(dane_vrfy_ctx->dane_vrfy_fp));
2371                         }
2372
2373                         if (tTd(96, 4))
2374                                 sm_dprintf("dane_verify, alg=%d, r=%d, len=%d\n",
2375                                         alg, r, dane_tlsa->dane_tlsa_len[i]);
2376                         if (r != dane_tlsa->dane_tlsa_len[i] - 3)
2377                                 continue;
2378                         ok = DANE_VRFY_FAIL;
2379
2380                         /*
2381                         **  Note: Type is NOT checked because only 3-1-x
2382                         **  is supported.
2383                         */
2384
2385                         if (memcmp(p + 3, fp, r) == 0)
2386                         {
2387                                 if (tTd(96, 2))
2388                                         sm_dprintf("dane_verify, status=match\n");
2389                                 if (tTd(96, 8))
2390                                 {
2391                                         unsigned char hex[256];
2392
2393                                         data2hex((unsigned char *)p,
2394                                                 dane_tlsa->dane_tlsa_len[i],
2395                                                 hex, sizeof(hex));
2396                                         sm_dprintf("dane_verify, pubkey_fp=%s\n"
2397                                                 , hex);
2398                                 }
2399                                 dane_vrfy_ctx->dane_vrfy_res = DANE_VRFY_OK;
2400                                 SM_FREE(fp);
2401                                 return DANE_VRFY_OK;
2402                         }
2403                 }
2404         }
2405
2406         SM_FREE(fp);
2407         dane_vrfy_ctx->dane_vrfy_res = ok;
2408         return ok;
2409 }
2410 # endif /* DANE */
2411
2412 /*
2413 **  TLS_VERIFY_CB -- verify callback for TLS certificates
2414 **
2415 **      Parameters:
2416 **              ctx -- X509 context
2417 **              cb_ctx -- callback context
2418 **
2419 **      Returns:
2420 **              accept connection?
2421 **              currently: always yes.
2422 */
2423
2424 static int
2425 tls_verify_cb(ctx, cb_ctx)
2426         X509_STORE_CTX *ctx;
2427         void *cb_ctx;
2428 {
2429         int ok;
2430 # if DANE
2431         SM_DECTLSI;
2432 # endif
2433
2434         /*
2435         **  SSL_CTX_set_cert_verify_callback(3):
2436         **  callback should return 1 to indicate verification success
2437         **  and 0 to indicate verification failure.
2438         */
2439
2440 # if DANE
2441         SM_GETTLSI;
2442         if (tlsi_ctx != NULL)
2443         {
2444                 dane_vrfy_ctx_P dane_vrfy_ctx;
2445
2446                 dane_vrfy_ctx = &(tlsi_ctx->tlsi_dvc);
2447                 ok = dane_verify(ctx, dane_vrfy_ctx);
2448                 if (tTd(96, 2))
2449                         sm_dprintf("dane_verify=%d, res=%d\n", ok,
2450                                 dane_vrfy_ctx->dane_vrfy_res);
2451                 if (ok != DANE_VRFY_NONE)
2452                         return 1;
2453         }
2454 # endif /* DANE */
2455
2456         ok = X509_verify_cert(ctx);
2457         if (ok <= 0)
2458         {
2459                 if (LogLevel > 13)
2460                         return tls_verify_log(ok, ctx, "TLS");
2461         }
2462         else if (LogLevel > 14)
2463                 (void) tls_verify_log(ok, ctx, "TLS");
2464         return 1;
2465 }
2466
2467 /*
2468 **  TLSLOGERR -- log the errors from the TLS error stack
2469 **
2470 **      Parameters:
2471 **              priority -- syslog priority
2472 **              ll -- loglevel
2473 **              who -- server/client (for logging).
2474 **
2475 **      Returns:
2476 **              none.
2477 */
2478
2479 void
2480 tlslogerr(priority, ll, who)
2481         int priority;
2482         int ll;
2483         const char *who;
2484 {
2485         unsigned long l;
2486         int line, flags;
2487         char *file, *data;
2488         char buf[256];
2489
2490         if (LogLevel <= ll)
2491                 return;
2492         while ((l = ERR_get_error_line_data((const char **) &file, &line,
2493                                             (const char **) &data, &flags))
2494                 != 0)
2495         {
2496                 sm_syslog(priority, NOQID,
2497                           "STARTTLS=%s: %s:%s:%d:%s", who,
2498                           ERR_error_string(l, buf),
2499                           file, line,
2500                           bitset(ERR_TXT_STRING, flags) ? data : "");
2501         }
2502 }
2503
2504 /*
2505 **  X509_VERIFY_CB -- verify callback
2506 **
2507 **      Parameters:
2508 **              ok -- current result
2509 **              ctx -- X509 context
2510 **
2511 **      Returns:
2512 **              accept connection?
2513 **              currently: always yes.
2514 */
2515
2516 static int
2517 x509_verify_cb(ok, ctx)
2518         int ok;
2519         X509_STORE_CTX *ctx;
2520 {
2521         SM_DECTLSI;
2522
2523         if (ok != 0)
2524                 return ok;
2525
2526         SM_GETTLSI;
2527         if (LogLevel > 13)
2528                 tls_verify_log(ok, ctx, "X509");
2529         if (X509_STORE_CTX_get_error(ctx) == X509_V_ERR_UNABLE_TO_GET_CRL &&
2530             !SM_TLSI_IS(tlsi_ctx, TLSI_FL_CRLREQ))
2531         {
2532                 X509_STORE_CTX_set_error(ctx, 0);
2533                 return 1;       /* override it */
2534         }
2535         return ok;
2536 }
2537
2538 # if !USE_OPENSSL_ENGINE
2539 /*
2540 **  TLS_SET_ENGINE -- set up ENGINE if needed
2541 **
2542 **      Parameters:
2543 **              id -- id for ENGINE
2544 **              isprefork -- called before fork()?
2545 **
2546 **      Returns: (OpenSSL "semantics", reverse it to allow returning error codes)
2547 **              0: failure
2548 **              !=0: ok
2549 */
2550
2551 int
2552 TLS_set_engine(id, isprefork)
2553         const char *id;
2554         bool isprefork;
2555 {
2556         static bool TLSEngineInitialized = false;
2557         ENGINE *e;
2558         char enginepath[MAXPATHLEN];
2559
2560         /*
2561         **  Todo: put error for logging into a string and log it in error:
2562         */
2563
2564         if (LogLevel > 13)
2565                 sm_syslog(LOG_DEBUG, NOQID,
2566                         "engine=%s, path=%s, ispre=%d, pre=%d, initialized=%d",
2567                         id, SSLEnginePath, isprefork, SSLEngineprefork,
2568                         TLSEngineInitialized);
2569         if (TLSEngineInitialized)
2570                 return 1;
2571         if (id == NULL || *id == '\0')
2572                 return 1;
2573
2574         /* is this the "right time" to initialize the engine? */
2575         if (isprefork != SSLEngineprefork)
2576                 return 1;
2577
2578         e = NULL;
2579         ENGINE_load_builtin_engines();
2580
2581         if (SSLEnginePath != NULL && *SSLEnginePath != '\0')
2582         {
2583                 if ((e = ENGINE_by_id("dynamic")) == NULL)
2584                 {
2585                         if (LogLevel > 1)
2586                                 sm_syslog(LOG_ERR, NOQID,
2587                                         "engine=%s, by_id=failed", "dynamic");
2588                         goto error;
2589                 }
2590                 (void) sm_snprintf(enginepath, sizeof(enginepath),
2591                         "%s/lib%s.so", SSLEnginePath, id);
2592
2593                 if (!ENGINE_ctrl_cmd_string(e, "SO_PATH", enginepath, 0))
2594                 {
2595                         if (LogLevel > 1)
2596                                 sm_syslog(LOG_ERR, NOQID,
2597                                         "engine=%s, SO_PATH=%s, status=failed",
2598                                         id, enginepath);
2599                         goto error;
2600                 }
2601
2602                 if (!ENGINE_ctrl_cmd_string(e, "ID", id, 0))
2603                 {
2604                         if (LogLevel > 1)
2605                                 sm_syslog(LOG_ERR, NOQID,
2606                                         "engine=%s, ID=failed", id);
2607                         goto error;
2608                 }
2609
2610                 if (!ENGINE_ctrl_cmd_string(e, "LOAD", NULL, 0))
2611                 {
2612                         if (LogLevel > 1)
2613                                 sm_syslog(LOG_ERR, NOQID,
2614                                         "engine=%s, LOAD=failed", id);
2615                         goto error;
2616                 }
2617         }
2618         else if ((e = ENGINE_by_id(id)) == NULL)
2619         {
2620                 if (LogLevel > 1)
2621                         sm_syslog(LOG_ERR, NOQID, "engine=%s, by_id=failed",
2622                                 id);
2623                 return 0;
2624         }
2625
2626         if (!ENGINE_init(e))
2627         {
2628                 if (LogLevel > 1)
2629                         sm_syslog(LOG_ERR, NOQID, "engine=%s, init=failed", id);
2630                 goto error;
2631         }
2632         if (!ENGINE_set_default(e, ENGINE_METHOD_ALL))
2633         {
2634                 if (LogLevel > 1)
2635                         sm_syslog(LOG_ERR, NOQID,
2636                                 "engine=%s, set_default=failed", id);
2637                 goto error;
2638         }
2639 #  ifdef ENGINE_CTRL_CHIL_SET_FORKCHECK
2640         if (strcmp(id, "chil") == 0)
2641                 ENGINE_ctrl(e, ENGINE_CTRL_CHIL_SET_FORKCHECK, 1, 0, 0);
2642 #  endif
2643
2644         /* Free our "structural" reference. */
2645         ENGINE_free(e);
2646         if (LogLevel > 10)
2647                 sm_syslog(LOG_INFO, NOQID, "engine=%s, loaded=ok", id);
2648         TLSEngineInitialized = true;
2649         return 1;
2650
2651   error:
2652         tlslogerr(LOG_WARNING, 7, "init");
2653         if (e != NULL)
2654                 ENGINE_free(e);
2655         return 0;
2656 }
2657 # endif /* !USE_OPENSSL_ENGINE */
2658 #endif /* STARTTLS */