contrib/sendmail/src/tls.c

   1 /*
   2  * Copyright (c) 2000-2006, 2008, 2009, 2011, 2013 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 <openssl/err.h>
  17 # include <openssl/bio.h>
  18 # include <openssl/pem.h>
  19 # if !NO_DH
  20 # include <openssl/dh.h>
  21 # endif /* !NO_DH */
  22 # ifndef HASURANDOMDEV
  23 #  include <openssl/rand.h>
  24 # endif /* ! HASURANDOMDEV */
  25 # if !TLS_NO_RSA
  26 static RSA *rsa_tmp = NULL;     /* temporary RSA key */
  27 static RSA *tmp_rsa_key __P((SSL *, int, int));
  28 # endif /* !TLS_NO_RSA */
  29 # if !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER < 0x00907000L
  30 static int      tls_verify_cb __P((X509_STORE_CTX *));
  31 # else /* !defined() || OPENSSL_VERSION_NUMBER < 0x00907000L */
  32 static int      tls_verify_cb __P((X509_STORE_CTX *, void *));
  33 # endif /* !defined() || OPENSSL_VERSION_NUMBER < 0x00907000L */
  34
  35 # if OPENSSL_VERSION_NUMBER > 0x00907000L
  36 static int x509_verify_cb __P((int, X509_STORE_CTX *));
  37 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */
  38
  39 # if !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER < 0x00907000L
  40 #  define CONST097
  41 # else /* !defined() || OPENSSL_VERSION_NUMBER < 0x00907000L */
  42 #  define CONST097 const
  43 # endif /* !defined() || OPENSSL_VERSION_NUMBER < 0x00907000L */
  44 static void     apps_ssl_info_cb __P((CONST097 SSL *, int , int));
  45 static bool     tls_ok_f __P((char *, char *, int));
  46 static bool     tls_safe_f __P((char *, long, bool));
  47 static int      tls_verify_log __P((int, X509_STORE_CTX *, const char *));
  48
  49 # if !NO_DH
  50 # if !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER < 0x10100001L || \
  51      (defined(LIBRESSL_VERSION_NUMBER) && LIBRESSL_VERSION_NUMBER < 0x20700000L)
  52 static int
  53 DH_set0_pqg(dh, p, q, g)
  54         DH *dh;
  55         BIGNUM *p;
  56         BIGNUM *q;
  57         BIGNUM *g;
  58 {
  59         dh->p=p;
  60         if (q != NULL)
  61                 dh->q=q;
  62         dh->g=g;
  63         return 1; /* success */
  64 }
  65 # endif /* !defined() || OPENSSL_VERSION_NUMBER < 0x00907000L */
  66
  67 static DH *get_dh512 __P((void));
  68
  69 static unsigned char dh512_p[] =
  70 {
  71         0xDA,0x58,0x3C,0x16,0xD9,0x85,0x22,0x89,0xD0,0xE4,0xAF,0x75,
  72         0x6F,0x4C,0xCA,0x92,0xDD,0x4B,0xE5,0x33,0xB8,0x04,0xFB,0x0F,
  73         0xED,0x94,0xEF,0x9C,0x8A,0x44,0x03,0xED,0x57,0x46,0x50,0xD3,
  74         0x69,0x99,0xDB,0x29,0xD7,0x76,0x27,0x6B,0xA2,0xD3,0xD4,0x12,
  75         0xE2,0x18,0xF4,0xDD,0x1E,0x08,0x4C,0xF6,0xD8,0x00,0x3E,0x7C,
  76         0x47,0x74,0xE8,0x33
  77 };
  78 static unsigned char dh512_g[] =
  79 {
  80         0x02
  81 };
  82
  83 static DH *
  84 get_dh512()
  85 {
  86         DH *dh = NULL;
  87         BIGNUM *dhp_bn, *dhg_bn;
  88
  89         if ((dh = DH_new()) == NULL)
  90                 return NULL;
  91         dhp_bn = BN_bin2bn(dh512_p, sizeof(dh512_p), NULL);
  92         dhg_bn = BN_bin2bn(dh512_g, sizeof(dh512_g), NULL);
  93         if ((dhp_bn == NULL) || (dhg_bn == NULL) || !DH_set0_pqg(dh, dhp_bn, NULL, dhg_bn))
  94         {
  95                 DH_free(dh);
  96                 BN_free(dhp_bn);
  97                 BN_free(dhg_bn);
  98                 return(NULL);
  99         }
 100         return dh;
 101 }
 102
 103 #  if 0
 104
 105 This is the data from which the C code has been generated:
 106
 107 -----BEGIN DH PARAMETERS-----
 108 MIIBCAKCAQEArDcgcLpxEksQHPlolRKCUJ2szKRziseWV9cUSQNZGxoGw7KkROz4
 109 HF9QSbg5axyNIG+QbZYtx0jp3l6/GWq1dLOj27yZkgYgaYgFrvKPiZ2jJ5xETQVH
 110 UpZwbjRcyjyWkWYJVsx1aF4F/iY4kT0n/+iGEoimI3C9V3KXTJ2S6jIkyJ6M/CrN
 111 EtrDynMlUMGlc7S1ouXVOTrtKeqy3S2L9eBLxVI+sChEijGIfELupdVeXihK006p
 112 MgnABPDbkTx6OOtYmSZaGQX+OLW2FPmwvcrzgCz9t9cAsuUcBZv1LeHEqZZttyLU
 113 oK0jjSXgFyeU4/NfyA+zuNeWzUL6bHmigwIBAg==
 114 -----END DH PARAMETERS-----
 115 #  endif /* 0 */
 116
 117 static DH *
 118 get_dh2048()
 119 {
 120         static unsigned char dh2048_p[]={
 121                 0xAC,0x37,0x20,0x70,0xBA,0x71,0x12,0x4B,0x10,0x1C,0xF9,0x68,
 122                 0x95,0x12,0x82,0x50,0x9D,0xAC,0xCC,0xA4,0x73,0x8A,0xC7,0x96,
 123                 0x57,0xD7,0x14,0x49,0x03,0x59,0x1B,0x1A,0x06,0xC3,0xB2,0xA4,
 124                 0x44,0xEC,0xF8,0x1C,0x5F,0x50,0x49,0xB8,0x39,0x6B,0x1C,0x8D,
 125                 0x20,0x6F,0x90,0x6D,0x96,0x2D,0xC7,0x48,0xE9,0xDE,0x5E,0xBF,
 126                 0x19,0x6A,0xB5,0x74,0xB3,0xA3,0xDB,0xBC,0x99,0x92,0x06,0x20,
 127                 0x69,0x88,0x05,0xAE,0xF2,0x8F,0x89,0x9D,0xA3,0x27,0x9C,0x44,
 128                 0x4D,0x05,0x47,0x52,0x96,0x70,0x6E,0x34,0x5C,0xCA,0x3C,0x96,
 129                 0x91,0x66,0x09,0x56,0xCC,0x75,0x68,0x5E,0x05,0xFE,0x26,0x38,
 130                 0x91,0x3D,0x27,0xFF,0xE8,0x86,0x12,0x88,0xA6,0x23,0x70,0xBD,
 131                 0x57,0x72,0x97,0x4C,0x9D,0x92,0xEA,0x32,0x24,0xC8,0x9E,0x8C,
 132                 0xFC,0x2A,0xCD,0x12,0xDA,0xC3,0xCA,0x73,0x25,0x50,0xC1,0xA5,
 133                 0x73,0xB4,0xB5,0xA2,0xE5,0xD5,0x39,0x3A,0xED,0x29,0xEA,0xB2,
 134                 0xDD,0x2D,0x8B,0xF5,0xE0,0x4B,0xC5,0x52,0x3E,0xB0,0x28,0x44,
 135                 0x8A,0x31,0x88,0x7C,0x42,0xEE,0xA5,0xD5,0x5E,0x5E,0x28,0x4A,
 136                 0xD3,0x4E,0xA9,0x32,0x09,0xC0,0x04,0xF0,0xDB,0x91,0x3C,0x7A,
 137                 0x38,0xEB,0x58,0x99,0x26,0x5A,0x19,0x05,0xFE,0x38,0xB5,0xB6,
 138                 0x14,0xF9,0xB0,0xBD,0xCA,0xF3,0x80,0x2C,0xFD,0xB7,0xD7,0x00,
 139                 0xB2,0xE5,0x1C,0x05,0x9B,0xF5,0x2D,0xE1,0xC4,0xA9,0x96,0x6D,
 140                 0xB7,0x22,0xD4,0xA0,0xAD,0x23,0x8D,0x25,0xE0,0x17,0x27,0x94,
 141                 0xE3,0xF3,0x5F,0xC8,0x0F,0xB3,0xB8,0xD7,0x96,0xCD,0x42,0xFA,
 142                 0x6C,0x79,0xA2,0x83,
 143                 };
 144         static unsigned char dh2048_g[]={ 0x02, };
 145         DH *dh;
 146         BIGNUM *dhp_bn, *dhg_bn;
 147
 148         if ((dh=DH_new()) == NULL)
 149                 return(NULL);
 150         dhp_bn = BN_bin2bn(dh2048_p,sizeof(dh2048_p),NULL);
 151         dhg_bn = BN_bin2bn(dh2048_g,sizeof(dh2048_g),NULL);
 152         if ((dhp_bn == NULL) || (dhg_bn == NULL) || !DH_set0_pqg(dh, dhp_bn, NULL, dhg_bn))
 153         {
 154                 DH_free(dh);
 155                 BN_free(dhp_bn);
 156                 BN_free(dhg_bn);
 157                 return(NULL);
 158         }
 159         return(dh);
 160 }
 161 # endif /* !NO_DH */
 162
 163
 164 /*
 165 **  TLS_RAND_INIT -- initialize STARTTLS random generator
 166 **
 167 **      Parameters:
 168 **              randfile -- name of file with random data
 169 **              logl -- loglevel
 170 **
 171 **      Returns:
 172 **              success/failure
 173 **
 174 **      Side Effects:
 175 **              initializes PRNG for tls library.
 176 */
 177
 178 # define MIN_RAND_BYTES 128     /* 1024 bits */
 179
 180 # define RF_OK          0       /* randfile OK */
 181 # define RF_MISS        1       /* randfile == NULL || *randfile == '\0' */
 182 # define RF_UNKNOWN     2       /* unknown prefix for randfile */
 183
 184 # define RI_NONE        0       /* no init yet */
 185 # define RI_SUCCESS     1       /* init was successful */
 186 # define RI_FAIL        2       /* init failed */
 187
 188 static bool     tls_rand_init __P((char *, int));
 189
 190 static bool
 191 tls_rand_init(randfile, logl)
 192         char *randfile;
 193         int logl;
 194 {
 195 # ifndef HASURANDOMDEV
 196         /* not required if /dev/urandom exists, OpenSSL does it internally */
 197
 198         bool ok;
 199         int randdef;
 200         static int done = RI_NONE;
 201
 202         /*
 203         **  initialize PRNG
 204         */
 205
 206         /* did we try this before? if yes: return old value */
 207         if (done != RI_NONE)
 208                 return done == RI_SUCCESS;
 209
 210         /* set default values */
 211         ok = false;
 212         done = RI_FAIL;
 213         randdef = (randfile == NULL || *randfile == '\0') ? RF_MISS : RF_OK;
 214 #   if EGD
 215         if (randdef == RF_OK && sm_strncasecmp(randfile, "egd:", 4) == 0)
 216         {
 217                 randfile += 4;
 218                 if (RAND_egd(randfile) < 0)
 219                 {
 220                         sm_syslog(LOG_WARNING, NOQID,
 221                                   "STARTTLS: RAND_egd(%s) failed: random number generator not seeded",
 222                                    randfile);
 223                 }
 224                 else
 225                         ok = true;
 226         }
 227         else
 228 #   endif /* EGD */
 229         if (randdef == RF_OK && sm_strncasecmp(randfile, "file:", 5) == 0)
 230         {
 231                 int fd;
 232                 long sff;
 233                 struct stat st;
 234
 235                 randfile += 5;
 236                 sff = SFF_SAFEDIRPATH | SFF_NOWLINK
 237                       | SFF_NOGWFILES | SFF_NOWWFILES
 238                       | SFF_NOGRFILES | SFF_NOWRFILES
 239                       | SFF_MUSTOWN | SFF_ROOTOK | SFF_OPENASROOT;
 240                 if (DontLockReadFiles)
 241                         sff |= SFF_NOLOCK;
 242                 if ((fd = safeopen(randfile, O_RDONLY, 0, sff)) >= 0)
 243                 {
 244                         if (fstat(fd, &st) < 0)
 245                         {
 246                                 if (LogLevel > logl)
 247                                         sm_syslog(LOG_ERR, NOQID,
 248                                                   "STARTTLS: can't fstat(%s)",
 249                                                   randfile);
 250                         }
 251                         else
 252                         {
 253                                 bool use, problem;
 254
 255                                 use = true;
 256                                 problem = false;
 257
 258                                 /* max. age of file: 10 minutes */
 259                                 if (st.st_mtime + 600 < curtime())
 260                                 {
 261                                         use = bitnset(DBS_INSUFFICIENTENTROPY,
 262                                                       DontBlameSendmail);
 263                                         problem = true;
 264                                         if (LogLevel > logl)
 265                                                 sm_syslog(LOG_ERR, NOQID,
 266                                                           "STARTTLS: RandFile %s too old: %s",
 267                                                           randfile,
 268                                                           use ? "unsafe" :
 269                                                                 "unusable");
 270                                 }
 271                                 if (use && st.st_size < MIN_RAND_BYTES)
 272                                 {
 273                                         use = bitnset(DBS_INSUFFICIENTENTROPY,
 274                                                       DontBlameSendmail);
 275                                         problem = true;
 276                                         if (LogLevel > logl)
 277                                                 sm_syslog(LOG_ERR, NOQID,
 278                                                           "STARTTLS: size(%s) < %d: %s",
 279                                                           randfile,
 280                                                           MIN_RAND_BYTES,
 281                                                           use ? "unsafe" :
 282                                                                 "unusable");
 283                                 }
 284                                 if (use)
 285                                         ok = RAND_load_file(randfile, -1) >=
 286                                              MIN_RAND_BYTES;
 287                                 if (use && !ok)
 288                                 {
 289                                         if (LogLevel > logl)
 290                                                 sm_syslog(LOG_WARNING, NOQID,
 291                                                           "STARTTLS: RAND_load_file(%s) failed: random number generator not seeded",
 292                                                           randfile);
 293                                 }
 294                                 if (problem)
 295                                         ok = false;
 296                         }
 297                         if (ok || bitnset(DBS_INSUFFICIENTENTROPY,
 298                                           DontBlameSendmail))
 299                         {
 300                                 /* add this even if fstat() failed */
 301                                 RAND_seed((void *) &st, sizeof(st));
 302                         }
 303                         (void) close(fd);
 304                 }
 305                 else
 306                 {
 307                         if (LogLevel > logl)
 308                                 sm_syslog(LOG_WARNING, NOQID,
 309                                           "STARTTLS: Warning: safeopen(%s) failed",
 310                                           randfile);
 311                 }
 312         }
 313         else if (randdef == RF_OK)
 314         {
 315                 if (LogLevel > logl)
 316                         sm_syslog(LOG_WARNING, NOQID,
 317                                   "STARTTLS: Error: no proper random file definition %s",
 318                                   randfile);
 319                 randdef = RF_UNKNOWN;
 320         }
 321         if (randdef == RF_MISS)
 322         {
 323                 if (LogLevel > logl)
 324                         sm_syslog(LOG_WARNING, NOQID,
 325                                   "STARTTLS: Error: missing random file definition");
 326         }
 327         if (!ok && bitnset(DBS_INSUFFICIENTENTROPY, DontBlameSendmail))
 328         {
 329                 int i;
 330                 long r;
 331                 unsigned char buf[MIN_RAND_BYTES];
 332
 333                 /* assert((MIN_RAND_BYTES % sizeof(long)) == 0); */
 334                 for (i = 0; i <= sizeof(buf) - sizeof(long); i += sizeof(long))
 335                 {
 336                         r = get_random();
 337                         (void) memcpy(buf + i, (void *) &r, sizeof(long));
 338                 }
 339                 RAND_seed(buf, sizeof(buf));
 340                 if (LogLevel > logl)
 341                         sm_syslog(LOG_WARNING, NOQID,
 342                                   "STARTTLS: Warning: random number generator not properly seeded");
 343                 ok = true;
 344         }
 345         done = ok ? RI_SUCCESS : RI_FAIL;
 346         return ok;
 347 # else /* ! HASURANDOMDEV */
 348         return true;
 349 # endif /* ! HASURANDOMDEV */
 350 }
 351 /*
 352 **  INIT_TLS_LIBRARY -- Calls functions which setup TLS library for global use.
 353 **
 354 **      Parameters:
 355 **              fipsmode -- use FIPS?
 356 **
 357 **      Returns:
 358 **              succeeded?
 359 */
 360
 361 bool
 362 init_tls_library(fipsmode)
 363         bool fipsmode;
 364 {
 365         bool bv;
 366
 367         /* basic TLS initialization, ignore result for now */
 368         SSL_library_init();
 369         SSL_load_error_strings();
 370         OpenSSL_add_all_algorithms();
 371 # if 0
 372         /* this is currently a macro for SSL_library_init */
 373         SSLeay_add_ssl_algorithms();
 374 # endif /* 0 */
 375
 376         bv = tls_rand_init(RandFile, 7);
 377 # if _FFR_FIPSMODE
 378         if (bv && fipsmode)
 379         {
 380                 if (!FIPS_mode_set(1))
 381                 {
 382                         unsigned long err;
 383
 384                         err = ERR_get_error();
 385                         if (LogLevel > 0)
 386                                 sm_syslog(LOG_ERR, NOQID,
 387                                         "STARTTLS=init, FIPSMode=%s",
 388                                         ERR_error_string(err, NULL));
 389                         return false;
 390                 }
 391                 else
 392                 {
 393                         if (LogLevel > 9)
 394                                 sm_syslog(LOG_INFO, NOQID,
 395                                         "STARTTLS=init, FIPSMode=ok");
 396                 }
 397         }
 398 #endif /* _FFR_FIPSMODE  */
 399         if (bv && CertFingerprintAlgorithm != NULL)
 400         {
 401                 const EVP_MD *md;
 402
 403                 md = EVP_get_digestbyname(CertFingerprintAlgorithm);
 404                 if (NULL == md)
 405                 {
 406                         bv = false;
 407                         if (LogLevel > 0)
 408                                 sm_syslog(LOG_ERR, NOQID,
 409                                         "STARTTLS=init, CertFingerprintAlgorithm=%s, status=invalid"
 410                                         , CertFingerprintAlgorithm);
 411                 }
 412                 else
 413                         EVP_digest = md;
 414         }
 415         return bv;
 416 }
 417
 418 /*
 419 **  TLS_SET_VERIFY -- request client certificate?
 420 **
 421 **      Parameters:
 422 **              ctx -- TLS context
 423 **              ssl -- TLS structure
 424 **              vrfy -- request certificate?
 425 **
 426 **      Returns:
 427 **              none.
 428 **
 429 **      Side Effects:
 430 **              Sets verification state for TLS
 431 **
 432 # if TLS_VRFY_PER_CTX
 433 **      Notice:
 434 **              This is per TLS context, not per TLS structure;
 435 **              the former is global, the latter per connection.
 436 **              It would be nice to do this per connection, but this
 437 **              doesn't work in the current TLS libraries :-(
 438 # endif * TLS_VRFY_PER_CTX *
 439 */
 440
 441 void
 442 tls_set_verify(ctx, ssl, vrfy)
 443         SSL_CTX *ctx;
 444         SSL *ssl;
 445         bool vrfy;
 446 {
 447 # if !TLS_VRFY_PER_CTX
 448         SSL_set_verify(ssl, vrfy ? SSL_VERIFY_PEER : SSL_VERIFY_NONE, NULL);
 449 # else /* !TLS_VRFY_PER_CTX */
 450         SSL_CTX_set_verify(ctx, vrfy ? SSL_VERIFY_PEER : SSL_VERIFY_NONE,
 451                         NULL);
 452 # endif /* !TLS_VRFY_PER_CTX */
 453 }
 454
 455 /*
 456 **  status in initialization
 457 **  these flags keep track of the status of the initialization
 458 **  i.e., whether a file exists (_EX) and whether it can be used (_OK)
 459 **  [due to permissions]
 460 */
 461
 462 # define TLS_S_NONE     0x00000000      /* none yet */
 463 # define TLS_S_CERT_EX  0x00000001      /* cert file exists */
 464 # define TLS_S_CERT_OK  0x00000002      /* cert file is ok */
 465 # define TLS_S_KEY_EX   0x00000004      /* key file exists */
 466 # define TLS_S_KEY_OK   0x00000008      /* key file is ok */
 467 # define TLS_S_CERTP_EX 0x00000010      /* CA cert path exists */
 468 # define TLS_S_CERTP_OK 0x00000020      /* CA cert path is ok */
 469 # define TLS_S_CERTF_EX 0x00000040      /* CA cert file exists */
 470 # define TLS_S_CERTF_OK 0x00000080      /* CA cert file is ok */
 471 # define TLS_S_CRLF_EX  0x00000100      /* CRL file exists */
 472 # define TLS_S_CRLF_OK  0x00000200      /* CRL file is ok */
 473
 474 # define TLS_S_CERT2_EX 0x00001000      /* 2nd cert file exists */
 475 # define TLS_S_CERT2_OK 0x00002000      /* 2nd cert file is ok */
 476 # define TLS_S_KEY2_EX  0x00004000      /* 2nd key file exists */
 477 # define TLS_S_KEY2_OK  0x00008000      /* 2nd key file is ok */
 478
 479 # define TLS_S_DH_OK    0x00200000      /* DH cert is ok */
 480 # define TLS_S_DHPAR_EX 0x00400000      /* DH param file exists */
 481 # define TLS_S_DHPAR_OK 0x00800000      /* DH param file is ok to use */
 482
 483 /* Type of variable */
 484 # define TLS_T_OTHER    0
 485 # define TLS_T_SRV      1
 486 # define TLS_T_CLT      2
 487
 488 /*
 489 **  TLS_OK_F -- can var be an absolute filename?
 490 **
 491 **      Parameters:
 492 **              var -- filename
 493 **              fn -- what is the filename used for?
 494 **              type -- type of variable
 495 **
 496 **      Returns:
 497 **              ok?
 498 */
 499
 500 static bool
 501 tls_ok_f(var, fn, type)
 502         char *var;
 503         char *fn;
 504         int type;
 505 {
 506         /* must be absolute pathname */
 507         if (var != NULL && *var == '/')
 508                 return true;
 509         if (LogLevel > 12)
 510                 sm_syslog(LOG_WARNING, NOQID, "STARTTLS: %s%s missing",
 511                           type == TLS_T_SRV ? "Server" :
 512                           (type == TLS_T_CLT ? "Client" : ""), fn);
 513         return false;
 514 }
 515 /*
 516 **  TLS_SAFE_F -- is a file safe to use?
 517 **
 518 **      Parameters:
 519 **              var -- filename
 520 **              sff -- flags for safefile()
 521 **              srv -- server side?
 522 **
 523 **      Returns:
 524 **              ok?
 525 */
 526
 527 static bool
 528 tls_safe_f(var, sff, srv)
 529         char *var;
 530         long sff;
 531         bool srv;
 532 {
 533         int ret;
 534
 535         if ((ret = safefile(var, RunAsUid, RunAsGid, RunAsUserName, sff,
 536                             S_IRUSR, NULL)) == 0)
 537                 return true;
 538         if (LogLevel > 7)
 539                 sm_syslog(LOG_WARNING, NOQID, "STARTTLS=%s: file %s unsafe: %s",
 540                           srv ? "server" : "client", var, sm_errstring(ret));
 541         return false;
 542 }
 543
 544 /*
 545 **  TLS_OK_F -- macro to simplify calls to tls_ok_f
 546 **
 547 **      Parameters:
 548 **              var -- filename
 549 **              fn -- what is the filename used for?
 550 **              req -- is the file required?
 551 **              st -- status bit to set if ok
 552 **              type -- type of variable
 553 **
 554 **      Side Effects:
 555 **              uses r, ok; may change ok and status.
 556 **
 557 */
 558
 559 # define TLS_OK_F(var, fn, req, st, type) if (ok) \
 560         { \
 561                 r = tls_ok_f(var, fn, type); \
 562                 if (r) \
 563                         status |= st; \
 564                 else if (req) \
 565                         ok = false; \
 566         }
 567
 568 /*
 569 **  TLS_UNR -- macro to return whether a file should be unreadable
 570 **
 571 **      Parameters:
 572 **              bit -- flag to test
 573 **              req -- flags
 574 **
 575 **      Returns:
 576 **              0/SFF_NORFILES
 577 */
 578 # define TLS_UNR(bit, req)      (bitset(bit, req) ? SFF_NORFILES : 0)
 579 # define TLS_OUNR(bit, req)     (bitset(bit, req) ? SFF_NOWRFILES : 0)
 580 # define TLS_KEYSFF(req)        \
 581         (bitnset(DBS_GROUPREADABLEKEYFILE, DontBlameSendmail) ? \
 582                 TLS_OUNR(TLS_I_KEY_OUNR, req) :                 \
 583                 TLS_UNR(TLS_I_KEY_UNR, req))
 584
 585 /*
 586 **  TLS_SAFE_F -- macro to simplify calls to tls_safe_f
 587 **
 588 **      Parameters:
 589 **              var -- filename
 590 **              sff -- flags for safefile()
 591 **              req -- is the file required?
 592 **              ex -- does the file exist?
 593 **              st -- status bit to set if ok
 594 **              srv -- server side?
 595 **
 596 **      Side Effects:
 597 **              uses r, ok, ex; may change ok and status.
 598 **
 599 */
 600
 601 # define TLS_SAFE_F(var, sff, req, ex, st, srv) if (ex && ok) \
 602         { \
 603                 r = tls_safe_f(var, sff, srv); \
 604                 if (r) \
 605                         status |= st;   \
 606                 else if (req) \
 607                         ok = false;     \
 608         }
 609
 610 # if _FFR_TLS_SE_OPTS
 611 /*
 612 **  LOAD_CERTKEY -- load cert/key for TLS session
 613 **
 614 **      Parameters:
 615 **              ssl -- TLS session context
 616 **              certfile -- filename of certificate
 617 **              keyfile -- filename of private key
 618 **
 619 **      Returns:
 620 **              succeeded?
 621 */
 622
 623 bool
 624 load_certkey(ssl, srv, certfile, keyfile)
 625         SSL *ssl;
 626         bool srv;
 627         char *certfile;
 628         char *keyfile;
 629 {
 630         bool ok;
 631         int r;
 632         long sff, status;
 633         unsigned long req;
 634         char *who;
 635
 636         ok = true;
 637         who = srv ? "server" : "client";
 638         status = TLS_S_NONE;
 639         req = TLS_I_CERT_EX|TLS_I_KEY_EX;
 640         TLS_OK_F(certfile, "CertFile", bitset(TLS_I_CERT_EX, req),
 641                  TLS_S_CERT_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 642         TLS_OK_F(keyfile, "KeyFile", bitset(TLS_I_KEY_EX, req),
 643                  TLS_S_KEY_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 644
 645         /* certfile etc. must be "safe". */
 646         sff = SFF_REGONLY | SFF_SAFEDIRPATH | SFF_NOWLINK
 647              | SFF_NOGWFILES | SFF_NOWWFILES
 648              | SFF_MUSTOWN | SFF_ROOTOK | SFF_OPENASROOT;
 649         if (DontLockReadFiles)
 650                 sff |= SFF_NOLOCK;
 651
 652         TLS_SAFE_F(certfile, sff | TLS_UNR(TLS_I_CERT_UNR, req),
 653                    bitset(TLS_I_CERT_EX, req),
 654                    bitset(TLS_S_CERT_EX, status), TLS_S_CERT_OK, srv);
 655         TLS_SAFE_F(keyfile, sff | TLS_KEYSFF(req),
 656                    bitset(TLS_I_KEY_EX, req),
 657                    bitset(TLS_S_KEY_EX, status), TLS_S_KEY_OK, srv);
 658
 659 # define SSL_use_cert(ssl, certfile) \
 660         SSL_use_certificate_file(ssl, certfile, SSL_FILETYPE_PEM)
 661 # define SSL_USE_CERT "SSL_use_certificate_file"
 662
 663         if (bitset(TLS_S_CERT_OK, status) &&
 664             SSL_use_cert(ssl, certfile) <= 0)
 665         {
 666                 if (LogLevel > 7)
 667                 {
 668                         sm_syslog(LOG_WARNING, NOQID,
 669                                   "STARTTLS=%s, error: %s(%s) failed",
 670                                   who, SSL_USE_CERT, certfile);
 671                         if (LogLevel > 9)
 672                                 tlslogerr(LOG_WARNING, who);
 673                 }
 674                 if (bitset(TLS_I_USE_CERT, req))
 675                         return false;
 676         }
 677         if (bitset(TLS_S_KEY_OK, status) &&
 678             SSL_use_PrivateKey_file(ssl, keyfile, SSL_FILETYPE_PEM) <= 0)
 679         {
 680                 if (LogLevel > 7)
 681                 {
 682                         sm_syslog(LOG_WARNING, NOQID,
 683                                   "STARTTLS=%s, error: SSL_use_PrivateKey_file(%s) failed",
 684                                   who, keyfile);
 685                         if (LogLevel > 9)
 686                                 tlslogerr(LOG_WARNING, who);
 687                 }
 688                 if (bitset(TLS_I_USE_KEY, req))
 689                         return false;
 690         }
 691
 692         /* check the private key */
 693         if (bitset(TLS_S_KEY_OK, status) &&
 694             (r = SSL_check_private_key(ssl)) <= 0)
 695         {
 696                 /* Private key does not match the certificate public key */
 697                 if (LogLevel > 5)
 698                 {
 699                         sm_syslog(LOG_WARNING, NOQID,
 700                                   "STARTTLS=%s, error: SSL_check_private_key failed(%s): %d",
 701                                   who, keyfile, r);
 702                         if (LogLevel > 9)
 703                                 tlslogerr(LOG_WARNING, who);
 704                 }
 705                 if (bitset(TLS_I_USE_KEY, req))
 706                         return false;
 707         }
 708
 709         return true;
 710 }
 711 # endif /* _FFR_TLS_SE_OPTS */
 712
 713 /*
 714 **  INITTLS -- initialize TLS
 715 **
 716 **      Parameters:
 717 **              ctx -- pointer to context
 718 **              req -- requirements for initialization (see sendmail.h)
 719 **              options -- options
 720 **              srv -- server side?
 721 **              certfile -- filename of certificate
 722 **              keyfile -- filename of private key
 723 **              cacertpath -- path to CAs
 724 **              cacertfile -- file with CA(s)
 725 **              dhparam -- parameters for DH
 726 **
 727 **      Returns:
 728 **              succeeded?
 729 */
 730
 731 /*
 732 **  The session_id_context identifies the service that created a session.
 733 **  This information is used to distinguish between multiple TLS-based
 734 **  servers running on the same server. We use the name of the mail system.
 735 **  Note: the session cache is not persistent.
 736 */
 737
 738 static char server_session_id_context[] = "sendmail8";
 739
 740 # if !TLS_NO_RSA
 741 static RSA *
 742 sm_RSA_generate_key(num, e)
 743         int num;
 744         unsigned long e;
 745 {
 746         RSA *rsa = NULL;
 747         BIGNUM *bn_rsa_r4;
 748         int rc;
 749
 750         bn_rsa_r4 = BN_new();
 751         rc = BN_set_word(bn_rsa_r4, RSA_F4);
 752         if ((bn_rsa_r4 != NULL) && BN_set_word(bn_rsa_r4, RSA_F4) && (rsa = RSA_new()) != NULL)
 753         {
 754                 if (!RSA_generate_key_ex(rsa, RSA_KEYLENGTH, bn_rsa_r4, NULL))
 755                 {
 756                         RSA_free(rsa);
 757                         rsa = NULL;
 758                 }
 759                 return NULL;
 760         }
 761         BN_free(bn_rsa_r4);
 762         return rsa;
 763 }
 764 # endif /* !TLS_NO_RSA */
 765
 766 /* 0.9.8a and b have a problem with SSL_OP_TLS_BLOCK_PADDING_BUG */
 767 #if (OPENSSL_VERSION_NUMBER >= 0x0090800fL)
 768 # define SM_SSL_OP_TLS_BLOCK_PADDING_BUG        1
 769 #else
 770 # define SM_SSL_OP_TLS_BLOCK_PADDING_BUG        0
 771 #endif
 772
 773 bool
 774 inittls(ctx, req, options, srv, certfile, keyfile, cacertpath, cacertfile, dhparam)
 775         SSL_CTX **ctx;
 776         unsigned long req;
 777         unsigned long options;
 778         bool srv;
 779         char *certfile, *keyfile, *cacertpath, *cacertfile, *dhparam;
 780 {
 781 # if !NO_DH
 782         static DH *dh = NULL;
 783 # endif /* !NO_DH */
 784         int r;
 785         bool ok;
 786         long sff, status;
 787         char *who;
 788         char *cf2, *kf2;
 789 # if SM_CONF_SHM
 790         extern int ShmId;
 791 # endif /* SM_CONF_SHM */
 792 # if OPENSSL_VERSION_NUMBER > 0x00907000L
 793         BIO *crl_file;
 794         X509_CRL *crl;
 795         X509_STORE *store;
 796 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */
 797 #if SM_SSL_OP_TLS_BLOCK_PADDING_BUG
 798         long rt_version;
 799         STACK_OF(SSL_COMP) *comp_methods;
 800 #endif
 801
 802         status = TLS_S_NONE;
 803         who = srv ? "server" : "client";
 804         if (ctx == NULL)
 805         {
 806                 syserr("STARTTLS=%s, inittls: ctx == NULL", who);
 807                 /* NOTREACHED */
 808                 SM_ASSERT(ctx != NULL);
 809         }
 810
 811         /* already initialized? (we could re-init...) */
 812         if (*ctx != NULL)
 813                 return true;
 814         ok = true;
 815
 816         /*
 817         **  look for a second filename: it must be separated by a ','
 818         **  no blanks allowed (they won't be skipped).
 819         **  we change a global variable here! this change will be undone
 820         **  before return from the function but only if it returns true.
 821         **  this isn't a problem since in a failure case this function
 822         **  won't be called again with the same (overwritten) values.
 823         **  otherwise each return must be replaced with a goto endinittls.
 824         */
 825
 826         cf2 = NULL;
 827         kf2 = NULL;
 828         if (certfile != NULL && (cf2 = strchr(certfile, ',')) != NULL)
 829         {
 830                 *cf2++ = '\0';
 831                 if (keyfile != NULL && (kf2 = strchr(keyfile, ',')) != NULL)
 832                         *kf2++ = '\0';
 833         }
 834
 835         /*
 836         **  Check whether files/paths are defined
 837         */
 838
 839         TLS_OK_F(certfile, "CertFile", bitset(TLS_I_CERT_EX, req),
 840                  TLS_S_CERT_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 841         TLS_OK_F(keyfile, "KeyFile", bitset(TLS_I_KEY_EX, req),
 842                  TLS_S_KEY_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 843         TLS_OK_F(cacertpath, "CACertPath", bitset(TLS_I_CERTP_EX, req),
 844                  TLS_S_CERTP_EX, TLS_T_OTHER);
 845         TLS_OK_F(cacertfile, "CACertFile", bitset(TLS_I_CERTF_EX, req),
 846                  TLS_S_CERTF_EX, TLS_T_OTHER);
 847
 848 # if OPENSSL_VERSION_NUMBER > 0x00907000L
 849         TLS_OK_F(CRLFile, "CRLFile", bitset(TLS_I_CRLF_EX, req),
 850                  TLS_S_CRLF_EX, TLS_T_OTHER);
 851 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */
 852
 853         /*
 854         **  if the second file is specified it must exist
 855         **  XXX: it is possible here to define only one of those files
 856         */
 857
 858         if (cf2 != NULL)
 859         {
 860                 TLS_OK_F(cf2, "CertFile", bitset(TLS_I_CERT_EX, req),
 861                          TLS_S_CERT2_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 862         }
 863         if (kf2 != NULL)
 864         {
 865                 TLS_OK_F(kf2, "KeyFile", bitset(TLS_I_KEY_EX, req),
 866                          TLS_S_KEY2_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 867         }
 868
 869         /*
 870         **  valid values for dhparam are (only the first char is checked)
 871         **  none        no parameters: don't use DH
 872         **  i           use precomputed 2048 bit parameters
 873         **  512         use precomputed 512 bit parameters
 874         **  1024        generate 1024 bit parameters
 875         **  2048        generate 2048 bit parameters
 876         **  /file/name  read parameters from /file/name
 877         */
 878
 879 #define SET_DH_DFL      \
 880         do {    \
 881                 dhparam = "I";  \
 882                 req |= TLS_I_DHFIXED;   \
 883         } while (0)
 884
 885         if (bitset(TLS_I_TRY_DH, req))
 886         {
 887                 if (dhparam != NULL)
 888                 {
 889                         char c = *dhparam;
 890
 891                         if (c == '1')
 892                                 req |= TLS_I_DH1024;
 893                         else if (c == 'I' || c == 'i')
 894                                 req |= TLS_I_DHFIXED;
 895                         else if (c == '2')
 896                                 req |= TLS_I_DH2048;
 897                         else if (c == '5')
 898                                 req |= TLS_I_DH512;
 899                         else if (c == 'n' || c == 'N')
 900                                 req &= ~TLS_I_TRY_DH;
 901                         else if (c != '/')
 902                         {
 903                                 if (LogLevel > 12)
 904                                         sm_syslog(LOG_WARNING, NOQID,
 905                                                   "STARTTLS=%s, error: illegal value '%s' for DHParameters",
 906                                                   who, dhparam);
 907                                 dhparam = NULL;
 908                         }
 909                 }
 910                 if (dhparam == NULL)
 911                         SET_DH_DFL;
 912                 else if (*dhparam == '/')
 913                 {
 914                         TLS_OK_F(dhparam, "DHParameters",
 915                                  bitset(TLS_I_DHPAR_EX, req),
 916                                  TLS_S_DHPAR_EX, TLS_T_OTHER);
 917                 }
 918         }
 919         if (!ok)
 920                 return ok;
 921
 922         /* certfile etc. must be "safe". */
 923         sff = SFF_REGONLY | SFF_SAFEDIRPATH | SFF_NOWLINK
 924              | SFF_NOGWFILES | SFF_NOWWFILES
 925              | SFF_MUSTOWN | SFF_ROOTOK | SFF_OPENASROOT;
 926         if (DontLockReadFiles)
 927                 sff |= SFF_NOLOCK;
 928
 929         TLS_SAFE_F(certfile, sff | TLS_UNR(TLS_I_CERT_UNR, req),
 930                    bitset(TLS_I_CERT_EX, req),
 931                    bitset(TLS_S_CERT_EX, status), TLS_S_CERT_OK, srv);
 932         TLS_SAFE_F(keyfile, sff | TLS_KEYSFF(req),
 933                    bitset(TLS_I_KEY_EX, req),
 934                    bitset(TLS_S_KEY_EX, status), TLS_S_KEY_OK, srv);
 935         TLS_SAFE_F(cacertfile, sff | TLS_UNR(TLS_I_CERTF_UNR, req),
 936                    bitset(TLS_I_CERTF_EX, req),
 937                    bitset(TLS_S_CERTF_EX, status), TLS_S_CERTF_OK, srv);
 938         if (dhparam != NULL && *dhparam == '/')
 939         {
 940                 TLS_SAFE_F(dhparam, sff | TLS_UNR(TLS_I_DHPAR_UNR, req),
 941                            bitset(TLS_I_DHPAR_EX, req),
 942                            bitset(TLS_S_DHPAR_EX, status), TLS_S_DHPAR_OK, srv);
 943                 if (!bitset(TLS_S_DHPAR_OK, status))
 944                         SET_DH_DFL;
 945         }
 946 # if OPENSSL_VERSION_NUMBER > 0x00907000L
 947         TLS_SAFE_F(CRLFile, sff | TLS_UNR(TLS_I_CRLF_UNR, req),
 948                    bitset(TLS_I_CRLF_EX, req),
 949                    bitset(TLS_S_CRLF_EX, status), TLS_S_CRLF_OK, srv);
 950 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */
 951         if (!ok)
 952                 return ok;
 953         if (cf2 != NULL)
 954         {
 955                 TLS_SAFE_F(cf2, sff | TLS_UNR(TLS_I_CERT_UNR, req),
 956                            bitset(TLS_I_CERT_EX, req),
 957                            bitset(TLS_S_CERT2_EX, status), TLS_S_CERT2_OK, srv);
 958         }
 959         if (kf2 != NULL)
 960         {
 961                 TLS_SAFE_F(kf2, sff | TLS_KEYSFF(req),
 962                            bitset(TLS_I_KEY_EX, req),
 963                            bitset(TLS_S_KEY2_EX, status), TLS_S_KEY2_OK, srv);
 964         }
 965
 966         /* create a method and a new context */
 967         if ((*ctx = SSL_CTX_new(srv ? SSLv23_server_method() :
 968                                       SSLv23_client_method())) == NULL)
 969         {
 970                 if (LogLevel > 7)
 971                         sm_syslog(LOG_WARNING, NOQID,
 972                                   "STARTTLS=%s, error: SSL_CTX_new(SSLv23_%s_method()) failed",
 973                                   who, who);
 974                 if (LogLevel > 9)
 975                         tlslogerr(LOG_WARNING, who);
 976                 return false;
 977         }
 978
 979 # if OPENSSL_VERSION_NUMBER > 0x00907000L
 980         if (CRLFile != NULL)
 981         {
 982                 /* get a pointer to the current certificate validation store */
 983                 store = SSL_CTX_get_cert_store(*ctx);   /* does not fail */
 984                 crl_file = BIO_new(BIO_s_file());
 985                 if (crl_file != NULL)
 986                 {
 987                         if (BIO_read_filename(crl_file, CRLFile) >= 0)
 988                         {
 989                                 crl = PEM_read_bio_X509_CRL(crl_file, NULL,
 990                                                         NULL, NULL);
 991                                 BIO_free(crl_file);
 992                                 X509_STORE_add_crl(store, crl);
 993                                 X509_CRL_free(crl);
 994                                 X509_STORE_set_flags(store,
 995                                         X509_V_FLAG_CRL_CHECK|X509_V_FLAG_CRL_CHECK_ALL);
 996                                 X509_STORE_set_verify_cb_func(store,
 997                                                 x509_verify_cb);
 998                         }
 999                         else
1000                         {
1001                                 if (LogLevel > 9)
1002                                 {
1003                                         sm_syslog(LOG_WARNING, NOQID,
1004                                                   "STARTTLS=%s, error: PEM_read_bio_X509_CRL(%s)=failed",
1005                                                   who, CRLFile);
1006                                 }
1007
1008                                 /* avoid memory leaks */
1009                                 BIO_free(crl_file);
1010                                 return false;
1011                         }
1012
1013                 }
1014                 else if (LogLevel > 9)
1015                         sm_syslog(LOG_WARNING, NOQID,
1016                                   "STARTTLS=%s, error: BIO_new=failed", who);
1017         }
1018         else
1019                 store = NULL;
1020 #  if _FFR_CRLPATH
1021         if (CRLPath != NULL && store != NULL)
1022         {
1023                 X509_LOOKUP *lookup;
1024
1025                 lookup = X509_STORE_add_lookup(store, X509_LOOKUP_hash_dir());
1026                 if (lookup == NULL)
1027                 {
1028                         if (LogLevel > 9)
1029                         {
1030                                 sm_syslog(LOG_WARNING, NOQID,
1031                                           "STARTTLS=%s, error: X509_STORE_add_lookup(hash)=failed",
1032                                           who, CRLFile);
1033                         }
1034                         return false;
1035                 }
1036                 X509_LOOKUP_add_dir(lookup, CRLPath, X509_FILETYPE_PEM);
1037                 X509_STORE_set_flags(store,
1038                         X509_V_FLAG_CRL_CHECK|X509_V_FLAG_CRL_CHECK_ALL);
1039         }
1040 #  endif /* _FFR_CRLPATH */
1041 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */
1042
1043 # if TLS_NO_RSA
1044         /* turn off backward compatibility, required for no-rsa */
1045         SSL_CTX_set_options(*ctx, SSL_OP_NO_SSLv2);
1046 # endif /* TLS_NO_RSA */
1047
1048
1049 # if !TLS_NO_RSA
1050         /*
1051         **  Create a temporary RSA key
1052         **  XXX  Maybe we shouldn't create this always (even though it
1053         **  is only at startup).
1054         **  It is a time-consuming operation and it is not always necessary.
1055         **  maybe we should do it only on demand...
1056         */
1057
1058         if (bitset(TLS_I_RSA_TMP, req)
1059 #  if SM_CONF_SHM
1060             && ShmId != SM_SHM_NO_ID &&
1061             (rsa_tmp = sm_RSA_generate_key(RSA_KEYLENGTH, RSA_F4)) == NULL
1062 #  else /* SM_CONF_SHM */
1063             && 0        /* no shared memory: no need to generate key now */
1064 #  endif /* SM_CONF_SHM */
1065            )
1066         {
1067                 if (LogLevel > 7)
1068                 {
1069                         sm_syslog(LOG_WARNING, NOQID,
1070                                   "STARTTLS=%s, error: RSA_generate_key failed",
1071                                   who);
1072                         if (LogLevel > 9)
1073                                 tlslogerr(LOG_WARNING, who);
1074                 }
1075                 return false;
1076         }
1077 # endif /* !TLS_NO_RSA */
1078
1079         /*
1080         **  load private key
1081         **  XXX change this for DSA-only version
1082         */
1083
1084         if (bitset(TLS_S_KEY_OK, status) &&
1085             SSL_CTX_use_PrivateKey_file(*ctx, keyfile,
1086                                          SSL_FILETYPE_PEM) <= 0)
1087         {
1088                 if (LogLevel > 7)
1089                 {
1090                         sm_syslog(LOG_WARNING, NOQID,
1091                                   "STARTTLS=%s, error: SSL_CTX_use_PrivateKey_file(%s) failed",
1092                                   who, keyfile);
1093                         if (LogLevel > 9)
1094                                 tlslogerr(LOG_WARNING, who);
1095                 }
1096                 if (bitset(TLS_I_USE_KEY, req))
1097                         return false;
1098         }
1099
1100 #if _FFR_TLS_USE_CERTIFICATE_CHAIN_FILE
1101 # define SSL_CTX_use_cert(ssl_ctx, certfile) \
1102         SSL_CTX_use_certificate_chain_file(ssl_ctx, certfile)
1103 # define SSL_CTX_USE_CERT "SSL_CTX_use_certificate_chain_file"
1104 #else
1105 # define SSL_CTX_use_cert(ssl_ctx, certfile) \
1106         SSL_CTX_use_certificate_file(ssl_ctx, certfile, SSL_FILETYPE_PEM)
1107 # define SSL_CTX_USE_CERT "SSL_CTX_use_certificate_file"
1108 #endif
1109
1110         /* get the certificate file */
1111         if (bitset(TLS_S_CERT_OK, status) &&
1112             SSL_CTX_use_cert(*ctx, certfile) <= 0)
1113         {
1114                 if (LogLevel > 7)
1115                 {
1116                         sm_syslog(LOG_WARNING, NOQID,
1117                                   "STARTTLS=%s, error: %s(%s) failed",
1118                                   who, SSL_CTX_USE_CERT, certfile);
1119                         if (LogLevel > 9)
1120                                 tlslogerr(LOG_WARNING, who);
1121                 }
1122                 if (bitset(TLS_I_USE_CERT, req))
1123                         return false;
1124         }
1125
1126         /* check the private key */
1127         if (bitset(TLS_S_KEY_OK, status) &&
1128             (r = SSL_CTX_check_private_key(*ctx)) <= 0)
1129         {
1130                 /* Private key does not match the certificate public key */
1131                 if (LogLevel > 5)
1132                 {
1133                         sm_syslog(LOG_WARNING, NOQID,
1134                                   "STARTTLS=%s, error: SSL_CTX_check_private_key failed(%s): %d",
1135                                   who, keyfile, r);
1136                         if (LogLevel > 9)
1137                                 tlslogerr(LOG_WARNING, who);
1138                 }
1139                 if (bitset(TLS_I_USE_KEY, req))
1140                         return false;
1141         }
1142
1143         /* XXX this code is pretty much duplicated from above! */
1144
1145         /* load private key */
1146         if (bitset(TLS_S_KEY2_OK, status) &&
1147             SSL_CTX_use_PrivateKey_file(*ctx, kf2, SSL_FILETYPE_PEM) <= 0)
1148         {
1149                 if (LogLevel > 7)
1150                 {
1151                         sm_syslog(LOG_WARNING, NOQID,
1152                                   "STARTTLS=%s, error: SSL_CTX_use_PrivateKey_file(%s) failed",
1153                                   who, kf2);
1154                         if (LogLevel > 9)
1155                                 tlslogerr(LOG_WARNING, who);
1156                 }
1157         }
1158
1159         /* get the certificate file */
1160         if (bitset(TLS_S_CERT2_OK, status) &&
1161             SSL_CTX_use_cert(*ctx, cf2) <= 0)
1162         {
1163                 if (LogLevel > 7)
1164                 {
1165                         sm_syslog(LOG_WARNING, NOQID,
1166                                   "STARTTLS=%s, error: %s(%s) failed",
1167                                   who, SSL_CTX_USE_CERT, cf2);
1168                         if (LogLevel > 9)
1169                                 tlslogerr(LOG_WARNING, who);
1170                 }
1171         }
1172
1173         /* also check the private key */
1174         if (bitset(TLS_S_KEY2_OK, status) &&
1175             (r = SSL_CTX_check_private_key(*ctx)) <= 0)
1176         {
1177                 /* Private key does not match the certificate public key */
1178                 if (LogLevel > 5)
1179                 {
1180                         sm_syslog(LOG_WARNING, NOQID,
1181                                   "STARTTLS=%s, error: SSL_CTX_check_private_key 2 failed: %d",
1182                                   who, r);
1183                         if (LogLevel > 9)
1184                                 tlslogerr(LOG_WARNING, who);
1185                 }
1186         }
1187
1188         /* SSL_CTX_set_quiet_shutdown(*ctx, 1); violation of standard? */
1189
1190 #if SM_SSL_OP_TLS_BLOCK_PADDING_BUG
1191
1192         /*
1193         **  In OpenSSL 0.9.8[ab], enabling zlib compression breaks the
1194         **  padding bug work-around, leading to false positives and
1195         **  failed connections. We may not interoperate with systems
1196         **  with the bug, but this is better than breaking on all 0.9.8[ab]
1197         **  systems that have zlib support enabled.
1198         **  Note: this checks the runtime version of the library, not
1199         **  just the compile time version.
1200         */
1201
1202         rt_version = SSLeay();
1203         if (rt_version >= 0x00908000L && rt_version <= 0x0090802fL)
1204         {
1205                 comp_methods = SSL_COMP_get_compression_methods();
1206                 if (comp_methods != NULL && sk_SSL_COMP_num(comp_methods) > 0)
1207                         options &= ~SSL_OP_TLS_BLOCK_PADDING_BUG;
1208         }
1209 #endif
1210         SSL_CTX_set_options(*ctx, (long) options);
1211
1212 # if !NO_DH
1213         /* Diffie-Hellman initialization */
1214         if (bitset(TLS_I_TRY_DH, req))
1215         {
1216 #if _FFR_TLS_EC
1217                 EC_KEY *ecdh;
1218 #endif /* _FFR_TLS_EC */
1219
1220                 if (tTd(96, 8))
1221                         sm_dprintf("inittls: req=%#lx, status=%#lx\n",
1222                                 req, status);
1223                 if (bitset(TLS_S_DHPAR_OK, status))
1224                 {
1225                         BIO *bio;
1226
1227                         if ((bio = BIO_new_file(dhparam, "r")) != NULL)
1228                         {
1229                                 dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL);
1230                                 BIO_free(bio);
1231                                 if (dh == NULL && LogLevel > 7)
1232                                 {
1233                                         unsigned long err;
1234
1235                                         err = ERR_get_error();
1236                                         sm_syslog(LOG_WARNING, NOQID,
1237                                                   "STARTTLS=%s, error: cannot read DH parameters(%s): %s",
1238                                                   who, dhparam,
1239                                                   ERR_error_string(err, NULL));
1240                                         if (LogLevel > 9)
1241                                                 tlslogerr(LOG_WARNING, who);
1242                                         SET_DH_DFL;
1243                                 }
1244                         }
1245                         else
1246                         {
1247                                 if (LogLevel > 5)
1248                                 {
1249                                         sm_syslog(LOG_WARNING, NOQID,
1250                                                   "STARTTLS=%s, error: BIO_new_file(%s) failed",
1251                                                   who, dhparam);
1252                                         if (LogLevel > 9)
1253                                                 tlslogerr(LOG_WARNING, who);
1254                                 }
1255                         }
1256                 }
1257                 if (dh == NULL && bitset(TLS_I_DH1024|TLS_I_DH2048, req))
1258                 {
1259                         int bits;
1260                         DSA *dsa;
1261
1262                         bits = bitset(TLS_I_DH2048, req) ? 2048 : 1024;
1263                         if (tTd(96, 2))
1264                                 sm_dprintf("inittls: Generating %d bit DH parameters\n", bits);
1265
1266                         dsa=DSA_new();
1267                         /* this takes a while! */
1268                         (void)DSA_generate_parameters_ex(dsa, bits, NULL, 0,
1269                                                          NULL, NULL, NULL);
1270                         dh = DSA_dup_DH(dsa);
1271                         DSA_free(dsa);
1272                 }
1273                 else if (dh == NULL && bitset(TLS_I_DHFIXED, req))
1274                 {
1275                         if (tTd(96, 2))
1276                                 sm_dprintf("inittls: Using precomputed 2048 bit DH parameters\n");
1277                         dh = get_dh2048();
1278                 }
1279                 else if (dh == NULL && bitset(TLS_I_DH512, req))
1280                 {
1281                         if (tTd(96, 2))
1282                                 sm_dprintf("inittls: Using precomputed 512 bit DH parameters\n");
1283                         dh = get_dh512();
1284                 }
1285
1286                 if (dh == NULL)
1287                 {
1288                         if (LogLevel > 9)
1289                         {
1290                                 unsigned long err;
1291
1292                                 err = ERR_get_error();
1293                                 sm_syslog(LOG_WARNING, NOQID,
1294                                           "STARTTLS=%s, error: cannot read or set DH parameters(%s): %s",
1295                                           who, dhparam,
1296                                           ERR_error_string(err, NULL));
1297                         }
1298                         if (bitset(TLS_I_REQ_DH, req))
1299                                 return false;
1300                 }
1301                 else
1302                 {
1303                         /* important to avoid small subgroup attacks */
1304                         SSL_CTX_set_options(*ctx, SSL_OP_SINGLE_DH_USE);
1305
1306                         SSL_CTX_set_tmp_dh(*ctx, dh);
1307                         if (LogLevel > 13)
1308                                 sm_syslog(LOG_INFO, NOQID,
1309                                           "STARTTLS=%s, Diffie-Hellman init, key=%d bit (%c)",
1310                                           who, 8 * DH_size(dh), *dhparam);
1311                         DH_free(dh);
1312                 }
1313
1314 #if _FFR_TLS_EC
1315                 ecdh = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1);
1316                 if (ecdh != NULL)
1317                 {
1318                         SSL_CTX_set_options(*ctx, SSL_OP_SINGLE_ECDH_USE);
1319                         SSL_CTX_set_tmp_ecdh(*ctx, ecdh);
1320                         EC_KEY_free(ecdh);
1321                 }
1322 #endif /* _FFR_TLS_EC */
1323
1324         }
1325 # endif /* !NO_DH */
1326
1327
1328         /* XXX do we need this cache here? */
1329         if (bitset(TLS_I_CACHE, req))
1330         {
1331                 SSL_CTX_sess_set_cache_size(*ctx, 1);
1332                 SSL_CTX_set_timeout(*ctx, 1);
1333                 SSL_CTX_set_session_id_context(*ctx,
1334                         (void *) &server_session_id_context,
1335                         sizeof(server_session_id_context));
1336                 (void) SSL_CTX_set_session_cache_mode(*ctx,
1337                                 SSL_SESS_CACHE_SERVER);
1338         }
1339         else
1340         {
1341                 (void) SSL_CTX_set_session_cache_mode(*ctx,
1342                                 SSL_SESS_CACHE_OFF);
1343         }
1344
1345         /* load certificate locations and default CA paths */
1346         if (bitset(TLS_S_CERTP_EX, status) && bitset(TLS_S_CERTF_EX, status))
1347         {
1348                 if ((r = SSL_CTX_load_verify_locations(*ctx, cacertfile,
1349                                                        cacertpath)) == 1)
1350                 {
1351 # if !TLS_NO_RSA
1352                         if (bitset(TLS_I_RSA_TMP, req))
1353                                 SSL_CTX_set_tmp_rsa_callback(*ctx, tmp_rsa_key);
1354 # endif /* !TLS_NO_RSA */
1355
1356                         /*
1357                         **  We have to install our own verify callback:
1358                         **  SSL_VERIFY_PEER requests a client cert but even
1359                         **  though *FAIL_IF* isn't set, the connection
1360                         **  will be aborted if the client presents a cert
1361                         **  that is not "liked" (can't be verified?) by
1362                         **  the TLS library :-(
1363                         */
1364
1365                         /*
1366                         **  XXX currently we could call tls_set_verify()
1367                         **  but we hope that that function will later on
1368                         **  only set the mode per connection.
1369                         */
1370                         SSL_CTX_set_verify(*ctx,
1371                                 bitset(TLS_I_NO_VRFY, req) ? SSL_VERIFY_NONE
1372                                                            : SSL_VERIFY_PEER,
1373                                 NULL);
1374
1375                         /* install verify callback */
1376                         SSL_CTX_set_cert_verify_callback(*ctx, tls_verify_cb,
1377                                                          NULL);
1378                         SSL_CTX_set_client_CA_list(*ctx,
1379                                 SSL_load_client_CA_file(cacertfile));
1380                 }
1381                 else
1382                 {
1383                         /*
1384                         **  can't load CA data; do we care?
1385                         **  the data is necessary to authenticate the client,
1386                         **  which in turn would be necessary
1387                         **  if we want to allow relaying based on it.
1388                         */
1389                         if (LogLevel > 5)
1390                         {
1391                                 sm_syslog(LOG_WARNING, NOQID,
1392                                           "STARTTLS=%s, error: load verify locs %s, %s failed: %d",
1393                                           who, cacertpath, cacertfile, r);
1394                                 if (LogLevel > 9)
1395                                         tlslogerr(LOG_WARNING, who);
1396                         }
1397                         if (bitset(TLS_I_VRFY_LOC, req))
1398                                 return false;
1399                 }
1400         }
1401
1402         /* XXX: make this dependent on an option? */
1403         if (tTd(96, 9))
1404                 SSL_CTX_set_info_callback(*ctx, apps_ssl_info_cb);
1405
1406         /* install our own cipher list */
1407         if (CipherList != NULL && *CipherList != '\0')
1408         {
1409                 if (SSL_CTX_set_cipher_list(*ctx, CipherList) <= 0)
1410                 {
1411                         if (LogLevel > 7)
1412                         {
1413                                 sm_syslog(LOG_WARNING, NOQID,
1414                                           "STARTTLS=%s, error: SSL_CTX_set_cipher_list(%s) failed, list ignored",
1415                                           who, CipherList);
1416
1417                                 if (LogLevel > 9)
1418                                         tlslogerr(LOG_WARNING, who);
1419                         }
1420                         /* failure if setting to this list is required? */
1421                 }
1422         }
1423
1424         if (LogLevel > 12)
1425                 sm_syslog(LOG_INFO, NOQID, "STARTTLS=%s, init=%d", who, ok);
1426
1427 # if 0
1428         /*
1429         **  this label is required if we want to have a "clean" exit
1430         **  see the comments above at the initialization of cf2
1431         */
1432
1433     endinittls:
1434 # endif /* 0 */
1435
1436         /* undo damage to global variables */
1437         if (cf2 != NULL)
1438                 *--cf2 = ',';
1439         if (kf2 != NULL)
1440                 *--kf2 = ',';
1441
1442         return ok;
1443 }
1444
1445 /*
1446 **  CERT_FP -- get cert fingerprint
1447 **
1448 **      Parameters:
1449 **              cert -- TLS cert
1450 **              mac -- macro storage
1451 **              macro -- where to store cert fp
1452 **
1453 **      Returns:
1454 **              <=0: cert fp calculation failed
1455 **              >0: cert fp calculation ok
1456 */
1457
1458 static int
1459 cert_fp(cert, evp_digest, mac, macro)
1460         X509 *cert;
1461         const EVP_MD *evp_digest;
1462         MACROS_T *mac;
1463         char *macro;
1464 {
1465         unsigned int n;
1466         int r;
1467         unsigned char md[EVP_MAX_MD_SIZE];
1468         char md5h[EVP_MAX_MD_SIZE * 3];
1469         static const char hexcodes[] = "0123456789ABCDEF";
1470
1471         n = 0;
1472         if (X509_digest(cert, EVP_digest, md, &n) == 0 || n <= 0)
1473         {
1474                 macdefine(mac, A_TEMP, macid(macro), "");
1475                 return 0;
1476         }
1477
1478         SM_ASSERT((n * 3) + 2 < sizeof(md5h));
1479         for (r = 0; r < (int) n; r++)
1480         {
1481                 md5h[r * 3] = hexcodes[(md[r] & 0xf0) >> 4];
1482                 md5h[(r * 3) + 1] = hexcodes[(md[r] & 0x0f)];
1483                 md5h[(r * 3) + 2] = ':';
1484         }
1485         md5h[(n * 3) - 1] = '\0';
1486         macdefine(mac, A_TEMP, macid(macro), md5h);
1487         return 1;
1488 }
1489
1490 /*
1491 **  TLS_GET_INFO -- get information about TLS connection
1492 **
1493 **      Parameters:
1494 **              ssl -- TLS connection structure
1495 **              srv -- server or client
1496 **              host -- hostname of other side
1497 **              mac -- macro storage
1498 **              certreq -- did we ask for a cert?
1499 **
1500 **      Returns:
1501 **              result of authentication.
1502 **
1503 **      Side Effects:
1504 **              sets various TLS related macros.
1505 */
1506
1507 int
1508 tls_get_info(ssl, srv, host, mac, certreq)
1509         SSL *ssl;
1510         bool srv;
1511         char *host;
1512         MACROS_T *mac;
1513         bool certreq;
1514 {
1515         const SSL_CIPHER *c;
1516         int b, r;
1517         long verifyok;
1518         char *s, *who;
1519         char bitstr[16];
1520         X509 *cert;
1521
1522         c = SSL_get_current_cipher(ssl);
1523
1524         /* cast is just workaround for compiler warning */
1525         macdefine(mac, A_TEMP, macid("{cipher}"),
1526                   (char *) SSL_CIPHER_get_name(c));
1527         b = SSL_CIPHER_get_bits(c, &r);
1528         (void) sm_snprintf(bitstr, sizeof(bitstr), "%d", b);
1529         macdefine(mac, A_TEMP, macid("{cipher_bits}"), bitstr);
1530         (void) sm_snprintf(bitstr, sizeof(bitstr), "%d", r);
1531         macdefine(mac, A_TEMP, macid("{alg_bits}"), bitstr);
1532         s = (char *) SSL_get_version(ssl);
1533         if (s == NULL)
1534                 s = "UNKNOWN";
1535         macdefine(mac, A_TEMP, macid("{tls_version}"), s);
1536
1537         who = srv ? "server" : "client";
1538         cert = SSL_get_peer_certificate(ssl);
1539         verifyok = SSL_get_verify_result(ssl);
1540         if (LogLevel > 14)
1541                 sm_syslog(LOG_INFO, NOQID,
1542                           "STARTTLS=%s, get_verify: %ld get_peer: 0x%lx",
1543                           who, verifyok, (unsigned long) cert);
1544         if (cert != NULL)
1545         {
1546                 X509_NAME *subj, *issuer;
1547                 char buf[MAXNAME];
1548
1549                 subj = X509_get_subject_name(cert);
1550                 issuer = X509_get_issuer_name(cert);
1551                 X509_NAME_oneline(subj, buf, sizeof(buf));
1552                 macdefine(mac, A_TEMP, macid("{cert_subject}"),
1553                          xtextify(buf, "<>\")"));
1554                 X509_NAME_oneline(issuer, buf, sizeof(buf));
1555                 macdefine(mac, A_TEMP, macid("{cert_issuer}"),
1556                          xtextify(buf, "<>\")"));
1557
1558 # define LL_BADCERT     8
1559
1560 #define CERTFPMACRO (CertFingerprintAlgorithm != NULL ? "{cert_fp}" : "{cert_md5}")
1561
1562 #define CHECK_X509_NAME(which)  \
1563         do {    \
1564                 if (r == -1)    \
1565                 {               \
1566                         sm_strlcpy(buf, "BadCertificateUnknown", sizeof(buf)); \
1567                         if (LogLevel > LL_BADCERT)      \
1568                                 sm_syslog(LOG_INFO, NOQID,      \
1569                                         "STARTTLS=%s, relay=%.100s, field=%s, status=failed to extract CN",     \
1570                                         who,    \
1571                                         host == NULL ? "local" : host,  \
1572                                         which); \
1573                 }               \
1574                 else if ((size_t)r >= sizeof(buf) - 1)  \
1575                 {               \
1576                         sm_strlcpy(buf, "BadCertificateTooLong", sizeof(buf)); \
1577                         if (LogLevel > 7)       \
1578                                 sm_syslog(LOG_INFO, NOQID,      \
1579                                         "STARTTLS=%s, relay=%.100s, field=%s, status=CN too long",      \
1580                                         who,    \
1581                                         host == NULL ? "local" : host,  \
1582                                         which); \
1583                 }               \
1584                 else if ((size_t)r > strlen(buf))       \
1585                 {               \
1586                         sm_strlcpy(buf, "BadCertificateContainsNUL",    \
1587                                 sizeof(buf));   \
1588                         if (LogLevel > 7)       \
1589                                 sm_syslog(LOG_INFO, NOQID,      \
1590                                         "STARTTLS=%s, relay=%.100s, field=%s, status=CN contains NUL",  \
1591                                         who,    \
1592                                         host == NULL ? "local" : host,  \
1593                                         which); \
1594                 }               \
1595         } while (0)
1596
1597                 r = X509_NAME_get_text_by_NID(subj, NID_commonName, buf,
1598                         sizeof buf);
1599                 CHECK_X509_NAME("cn_subject");
1600                 macdefine(mac, A_TEMP, macid("{cn_subject}"),
1601                          xtextify(buf, "<>\")"));
1602                 r = X509_NAME_get_text_by_NID(issuer, NID_commonName, buf,
1603                         sizeof buf);
1604                 CHECK_X509_NAME("cn_issuer");
1605                 macdefine(mac, A_TEMP, macid("{cn_issuer}"),
1606                          xtextify(buf, "<>\")"));
1607                 (void) cert_fp(cert, EVP_digest, mac, CERTFPMACRO);
1608         }
1609         else
1610         {
1611                 macdefine(mac, A_PERM, macid("{cert_subject}"), "");
1612                 macdefine(mac, A_PERM, macid("{cert_issuer}"), "");
1613                 macdefine(mac, A_PERM, macid("{cn_subject}"), "");
1614                 macdefine(mac, A_PERM, macid("{cn_issuer}"), "");
1615                 macdefine(mac, A_TEMP, macid(CERTFPMACRO), "");
1616         }
1617         switch (verifyok)
1618         {
1619           case X509_V_OK:
1620                 if (cert != NULL)
1621                 {
1622                         s = "OK";
1623                         r = TLS_AUTH_OK;
1624                 }
1625                 else
1626                 {
1627                         s = certreq ? "NO" : "NOT",
1628                         r = TLS_AUTH_NO;
1629                 }
1630                 break;
1631           default:
1632                 s = "FAIL";
1633                 r = TLS_AUTH_FAIL;
1634                 break;
1635         }
1636         macdefine(mac, A_PERM, macid("{verify}"), s);
1637         if (cert != NULL)
1638                 X509_free(cert);
1639
1640         /* do some logging */
1641         if (LogLevel > 8)
1642         {
1643                 char *vers, *s1, *s2, *cbits, *algbits;
1644
1645                 vers = macget(mac, macid("{tls_version}"));
1646                 cbits = macget(mac, macid("{cipher_bits}"));
1647                 algbits = macget(mac, macid("{alg_bits}"));
1648                 s1 = macget(mac, macid("{verify}"));
1649                 s2 = macget(mac, macid("{cipher}"));
1650
1651                 /* XXX: maybe cut off ident info? */
1652                 sm_syslog(LOG_INFO, NOQID,
1653                           "STARTTLS=%s, relay=%.100s, version=%.16s, verify=%.16s, cipher=%.64s, bits=%.6s/%.6s",
1654                           who,
1655                           host == NULL ? "local" : host,
1656                           vers, s1, s2, /* sm_snprintf() can deal with NULL */
1657                           algbits == NULL ? "0" : algbits,
1658                           cbits == NULL ? "0" : cbits);
1659                 if (LogLevel > 11)
1660                 {
1661                         /*
1662                         **  Maybe run xuntextify on the strings?
1663                         **  That is easier to read but makes it maybe a bit
1664                         **  more complicated to figure out the right values
1665                         **  for the access map...
1666                         */
1667
1668                         s1 = macget(mac, macid("{cert_subject}"));
1669                         s2 = macget(mac, macid("{cert_issuer}"));
1670                         sm_syslog(LOG_INFO, NOQID,
1671                                   "STARTTLS=%s, cert-subject=%.256s, cert-issuer=%.256s, verifymsg=%s",
1672                                   who, s1, s2,
1673                                   X509_verify_cert_error_string(verifyok));
1674                 }
1675         }
1676         return r;
1677 }
1678 /*
1679 **  ENDTLS -- shutdown secure connection
1680 **
1681 **      Parameters:
1682 **              ssl -- SSL connection information.
1683 **              side -- server/client (for logging).
1684 **
1685 **      Returns:
1686 **              success? (EX_* code)
1687 */
1688
1689 int
1690 endtls(ssl, side)
1691         SSL *ssl;
1692         char *side;
1693 {
1694         int ret = EX_OK;
1695
1696         if (ssl != NULL)
1697         {
1698                 int r;
1699
1700                 if ((r = SSL_shutdown(ssl)) < 0)
1701                 {
1702                         if (LogLevel > 11)
1703                         {
1704                                 sm_syslog(LOG_WARNING, NOQID,
1705                                           "STARTTLS=%s, SSL_shutdown failed: %d",
1706                                           side, r);
1707                                 tlslogerr(LOG_WARNING, side);
1708                         }
1709                         ret = EX_SOFTWARE;
1710                 }
1711 # if !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER > 0x0090602fL
1712
1713                 /*
1714                 **  Bug in OpenSSL (at least up to 0.9.6b):
1715                 **  From: Lutz.Jaenicke@aet.TU-Cottbus.DE
1716                 **  Message-ID: <20010723152244.A13122@serv01.aet.tu-cottbus.de>
1717                 **  To: openssl-users@openssl.org
1718                 **  Subject: Re: SSL_shutdown() woes (fwd)
1719                 **
1720                 **  The side sending the shutdown alert first will
1721                 **  not care about the answer of the peer but will
1722                 **  immediately return with a return value of "0"
1723                 **  (ssl/s3_lib.c:ssl3_shutdown()). SSL_get_error will evaluate
1724                 **  the value of "0" and as the shutdown alert of the peer was
1725                 **  not received (actually, the program did not even wait for
1726                 **  the answer), an SSL_ERROR_SYSCALL is flagged, because this
1727                 **  is the default rule in case everything else does not apply.
1728                 **
1729                 **  For your server the problem is different, because it
1730                 **  receives the shutdown first (setting SSL_RECEIVED_SHUTDOWN),
1731                 **  then sends its response (SSL_SENT_SHUTDOWN), so for the
1732                 **  server the shutdown was successfull.
1733                 **
1734                 **  As is by know, you would have to call SSL_shutdown() once
1735                 **  and ignore an SSL_ERROR_SYSCALL returned. Then call
1736                 **  SSL_shutdown() again to actually get the server's response.
1737                 **
1738                 **  In the last discussion, Bodo Moeller concluded that a
1739                 **  rewrite of the shutdown code would be necessary, but
1740                 **  probably with another API, as the change would not be
1741                 **  compatible to the way it is now.  Things do not become
1742                 **  easier as other programs do not follow the shutdown
1743                 **  guidelines anyway, so that a lot error conditions and
1744                 **  compitibility issues would have to be caught.
1745                 **
1746                 **  For now the recommondation is to ignore the error message.
1747                 */
1748
1749                 else if (r == 0)
1750                 {
1751                         if (LogLevel > 15)
1752                         {
1753                                 sm_syslog(LOG_WARNING, NOQID,
1754                                           "STARTTLS=%s, SSL_shutdown not done",
1755                                           side);
1756                                 tlslogerr(LOG_WARNING, side);
1757                         }
1758                         ret = EX_SOFTWARE;
1759                 }
1760 # endif /* !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER > 0x0090602fL */
1761                 SSL_free(ssl);
1762                 ssl = NULL;
1763         }
1764         return ret;
1765 }
1766
1767 # if !TLS_NO_RSA
1768 /*
1769 **  TMP_RSA_KEY -- return temporary RSA key
1770 **
1771 **      Parameters:
1772 **              s -- TLS connection structure
1773 **              export --
1774 **              keylength --
1775 **
1776 **      Returns:
1777 **              temporary RSA key.
1778 */
1779
1780 #   ifndef MAX_RSA_TMP_CNT
1781 #    define MAX_RSA_TMP_CNT     1000    /* XXX better value? */
1782 #   endif /* ! MAX_RSA_TMP_CNT */
1783
1784 /* ARGUSED0 */
1785 static RSA *
1786 tmp_rsa_key(s, export, keylength)
1787         SSL *s;
1788         int export;
1789         int keylength;
1790 {
1791 #   if SM_CONF_SHM
1792         extern int ShmId;
1793         extern int *PRSATmpCnt;
1794
1795         if (ShmId != SM_SHM_NO_ID && rsa_tmp != NULL &&
1796             ++(*PRSATmpCnt) < MAX_RSA_TMP_CNT)
1797                 return rsa_tmp;
1798 #   endif /* SM_CONF_SHM */
1799
1800         if (rsa_tmp != NULL)
1801                 RSA_free(rsa_tmp);
1802         rsa_tmp = sm_RSA_generate_key(RSA_KEYLENGTH, RSA_F4);
1803         if (rsa_tmp == NULL)
1804         {
1805                 if (LogLevel > 0)
1806                         sm_syslog(LOG_ERR, NOQID,
1807                                   "STARTTLS=server, tmp_rsa_key: RSA_generate_key failed!");
1808         }
1809         else
1810         {
1811 #   if SM_CONF_SHM
1812 #    if 0
1813                 /*
1814                 **  XXX we can't (yet) share the new key...
1815                 **      The RSA structure contains pointers hence it can't be
1816                 **      easily kept in shared memory.  It must be transformed
1817                 **      into a continous memory region first, then stored,
1818                 **      and later read out again (each time re-transformed).
1819                 */
1820
1821                 if (ShmId != SM_SHM_NO_ID)
1822                         *PRSATmpCnt = 0;
1823 #    endif /* 0 */
1824 #   endif /* SM_CONF_SHM */
1825                 if (LogLevel > 9)
1826                         sm_syslog(LOG_ERR, NOQID,
1827                                   "STARTTLS=server, tmp_rsa_key: new temp RSA key");
1828         }
1829         return rsa_tmp;
1830 }
1831 # endif /* !TLS_NO_RSA */
1832 /*
1833 **  APPS_SSL_INFO_CB -- info callback for TLS connections
1834 **
1835 **      Parameters:
1836 **              s -- TLS connection structure
1837 **              where -- state in handshake
1838 **              ret -- return code of last operation
1839 **
1840 **      Returns:
1841 **              none.
1842 */
1843
1844 static void
1845 apps_ssl_info_cb(s, where, ret)
1846         CONST097 SSL *s;
1847         int where;
1848         int ret;
1849 {
1850         int w;
1851         char *str;
1852         BIO *bio_err = NULL;
1853
1854         if (LogLevel > 14)
1855                 sm_syslog(LOG_INFO, NOQID,
1856                           "STARTTLS: info_callback where=0x%x, ret=%d",
1857                           where, ret);
1858
1859         w = where & ~SSL_ST_MASK;
1860         if (bio_err == NULL)
1861                 bio_err = BIO_new_fp(stderr, BIO_NOCLOSE);
1862
1863         if (bitset(SSL_ST_CONNECT, w))
1864                 str = "SSL_connect";
1865         else if (bitset(SSL_ST_ACCEPT, w))
1866                 str = "SSL_accept";
1867         else
1868                 str = "undefined";
1869
1870         if (bitset(SSL_CB_LOOP, where))
1871         {
1872                 if (LogLevel > 12)
1873                         sm_syslog(LOG_NOTICE, NOQID,
1874                                 "STARTTLS: %s:%s",
1875                                 str, SSL_state_string_long(s));
1876         }
1877         else if (bitset(SSL_CB_ALERT, where))
1878         {
1879                 str = bitset(SSL_CB_READ, where) ? "read" : "write";
1880                 if (LogLevel > 12)
1881                         sm_syslog(LOG_NOTICE, NOQID,
1882                                 "STARTTLS: SSL3 alert %s:%s:%s",
1883                                 str, SSL_alert_type_string_long(ret),
1884                                 SSL_alert_desc_string_long(ret));
1885         }
1886         else if (bitset(SSL_CB_EXIT, where))
1887         {
1888                 if (ret == 0)
1889                 {
1890                         if (LogLevel > 7)
1891                                 sm_syslog(LOG_WARNING, NOQID,
1892                                         "STARTTLS: %s:failed in %s",
1893                                         str, SSL_state_string_long(s));
1894                 }
1895                 else if (ret < 0)
1896                 {
1897                         if (LogLevel > 7)
1898                                 sm_syslog(LOG_WARNING, NOQID,
1899                                         "STARTTLS: %s:error in %s",
1900                                         str, SSL_state_string_long(s));
1901                 }
1902         }
1903 }
1904 /*
1905 **  TLS_VERIFY_LOG -- log verify error for TLS certificates
1906 **
1907 **      Parameters:
1908 **              ok -- verify ok?
1909 **              ctx -- x509 context
1910 **              name -- from where is this called?
1911 **
1912 **      Returns:
1913 **              1 -- ok
1914 */
1915
1916 static int
1917 tls_verify_log(ok, ctx, name)
1918         int ok;
1919         X509_STORE_CTX *ctx;
1920         const char *name;
1921 {
1922         X509 *cert;
1923         int reason, depth;
1924         char buf[512];
1925
1926         cert = X509_STORE_CTX_get_current_cert(ctx);
1927         reason = X509_STORE_CTX_get_error(ctx);
1928         depth = X509_STORE_CTX_get_error_depth(ctx);
1929         X509_NAME_oneline(X509_get_subject_name(cert), buf, sizeof(buf));
1930         sm_syslog(LOG_INFO, NOQID,
1931                   "STARTTLS: %s cert verify: depth=%d %s, state=%d, reason=%s",
1932                   name, depth, buf, ok, X509_verify_cert_error_string(reason));
1933         return 1;
1934 }
1935
1936 /*
1937 **  TLS_VERIFY_CB -- verify callback for TLS certificates
1938 **
1939 **      Parameters:
1940 **              ctx -- x509 context
1941 **
1942 **      Returns:
1943 **              accept connection?
1944 **              currently: always yes.
1945 */
1946
1947 static int
1948 #  if !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER < 0x00907000L
1949 tls_verify_cb(ctx)
1950         X509_STORE_CTX *ctx;
1951 #  else /* !defined() || OPENSSL_VERSION_NUMBER < 0x00907000L */
1952 tls_verify_cb(ctx, unused)
1953         X509_STORE_CTX *ctx;
1954         void *unused;
1955 #  endif /* !defined() || OPENSSL_VERSION_NUMBER < 0x00907000L */
1956 {
1957         int ok;
1958
1959         /*
1960         **  man SSL_CTX_set_cert_verify_callback():
1961         **  callback should return 1 to indicate verification success
1962         **  and 0 to indicate verification failure.
1963         */
1964
1965         ok = X509_verify_cert(ctx);
1966         if (ok <= 0)
1967         {
1968                 if (LogLevel > 13)
1969                         return tls_verify_log(ok, ctx, "TLS");
1970         }
1971         return 1;
1972 }
1973 /*
1974 **  TLSLOGERR -- log the errors from the TLS error stack
1975 **
1976 **      Parameters:
1977 **              level -- syslog level
1978 **              who -- server/client (for logging).
1979 **
1980 **      Returns:
1981 **              none.
1982 */
1983
1984 void
1985 tlslogerr(level, who)
1986         int level;
1987         const char *who;
1988 {
1989         unsigned long l;
1990         int line, flags;
1991         unsigned long es;
1992         char *file, *data;
1993         char buf[256];
1994
1995         es = CRYPTO_thread_id();
1996         while ((l = ERR_get_error_line_data((const char **) &file, &line,
1997                                             (const char **) &data, &flags))
1998                 != 0)
1999         {
2000                 sm_syslog(level, NOQID,
2001                           "STARTTLS=%s: %lu:%s:%s:%d:%s", who, es,
2002                           ERR_error_string(l, buf),
2003                           file, line,
2004                           bitset(ERR_TXT_STRING, flags) ? data : "");
2005         }
2006 }
2007
2008 # if OPENSSL_VERSION_NUMBER > 0x00907000L
2009 /*
2010 **  X509_VERIFY_CB -- verify callback
2011 **
2012 **      Parameters:
2013 **              ctx -- x509 context
2014 **
2015 **      Returns:
2016 **              accept connection?
2017 **              currently: always yes.
2018 */
2019
2020 static int
2021 x509_verify_cb(ok, ctx)
2022         int ok;
2023         X509_STORE_CTX *ctx;
2024 {
2025         if (ok == 0)
2026         {
2027                 if (LogLevel > 13)
2028                         tls_verify_log(ok, ctx, "x509");
2029                 if (X509_STORE_CTX_get_error(ctx) == X509_V_ERR_UNABLE_TO_GET_CRL)
2030                 {
2031                         X509_STORE_CTX_set_error(ctx, 0);
2032                         return 1;       /* override it */
2033                 }
2034         }
2035         return ok;
2036 }
2037 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */
2038 #endif /* STARTTLS */