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;
  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))
  94         {
  95                 DH_free(dh);
  96                 BN_free(dhp_bn);
  97                 BN_free(dhg_bn);
  98                 return NULL;
  99         }
 100         if (!DH_set0_pqg(dh, dhp_bn, NULL, dhg_bn))
 101         {
 102                 DH_free(dh);
 103                 return NULL;
 104         }
 105         return dh;
 106 }
 107
 108 #  if 0
 109
 110 This is the data from which the C code has been generated:
 111
 112 -----BEGIN DH PARAMETERS-----
 113 MIIBCAKCAQEArDcgcLpxEksQHPlolRKCUJ2szKRziseWV9cUSQNZGxoGw7KkROz4
 114 HF9QSbg5axyNIG+QbZYtx0jp3l6/GWq1dLOj27yZkgYgaYgFrvKPiZ2jJ5xETQVH
 115 UpZwbjRcyjyWkWYJVsx1aF4F/iY4kT0n/+iGEoimI3C9V3KXTJ2S6jIkyJ6M/CrN
 116 EtrDynMlUMGlc7S1ouXVOTrtKeqy3S2L9eBLxVI+sChEijGIfELupdVeXihK006p
 117 MgnABPDbkTx6OOtYmSZaGQX+OLW2FPmwvcrzgCz9t9cAsuUcBZv1LeHEqZZttyLU
 118 oK0jjSXgFyeU4/NfyA+zuNeWzUL6bHmigwIBAg==
 119 -----END DH PARAMETERS-----
 120 #  endif /* 0 */
 121
 122 static DH *
 123 get_dh2048()
 124 {
 125         static unsigned char dh2048_p[] = {
 126                 0xAC,0x37,0x20,0x70,0xBA,0x71,0x12,0x4B,0x10,0x1C,0xF9,0x68,
 127                 0x95,0x12,0x82,0x50,0x9D,0xAC,0xCC,0xA4,0x73,0x8A,0xC7,0x96,
 128                 0x57,0xD7,0x14,0x49,0x03,0x59,0x1B,0x1A,0x06,0xC3,0xB2,0xA4,
 129                 0x44,0xEC,0xF8,0x1C,0x5F,0x50,0x49,0xB8,0x39,0x6B,0x1C,0x8D,
 130                 0x20,0x6F,0x90,0x6D,0x96,0x2D,0xC7,0x48,0xE9,0xDE,0x5E,0xBF,
 131                 0x19,0x6A,0xB5,0x74,0xB3,0xA3,0xDB,0xBC,0x99,0x92,0x06,0x20,
 132                 0x69,0x88,0x05,0xAE,0xF2,0x8F,0x89,0x9D,0xA3,0x27,0x9C,0x44,
 133                 0x4D,0x05,0x47,0x52,0x96,0x70,0x6E,0x34,0x5C,0xCA,0x3C,0x96,
 134                 0x91,0x66,0x09,0x56,0xCC,0x75,0x68,0x5E,0x05,0xFE,0x26,0x38,
 135                 0x91,0x3D,0x27,0xFF,0xE8,0x86,0x12,0x88,0xA6,0x23,0x70,0xBD,
 136                 0x57,0x72,0x97,0x4C,0x9D,0x92,0xEA,0x32,0x24,0xC8,0x9E,0x8C,
 137                 0xFC,0x2A,0xCD,0x12,0xDA,0xC3,0xCA,0x73,0x25,0x50,0xC1,0xA5,
 138                 0x73,0xB4,0xB5,0xA2,0xE5,0xD5,0x39,0x3A,0xED,0x29,0xEA,0xB2,
 139                 0xDD,0x2D,0x8B,0xF5,0xE0,0x4B,0xC5,0x52,0x3E,0xB0,0x28,0x44,
 140                 0x8A,0x31,0x88,0x7C,0x42,0xEE,0xA5,0xD5,0x5E,0x5E,0x28,0x4A,
 141                 0xD3,0x4E,0xA9,0x32,0x09,0xC0,0x04,0xF0,0xDB,0x91,0x3C,0x7A,
 142                 0x38,0xEB,0x58,0x99,0x26,0x5A,0x19,0x05,0xFE,0x38,0xB5,0xB6,
 143                 0x14,0xF9,0xB0,0xBD,0xCA,0xF3,0x80,0x2C,0xFD,0xB7,0xD7,0x00,
 144                 0xB2,0xE5,0x1C,0x05,0x9B,0xF5,0x2D,0xE1,0xC4,0xA9,0x96,0x6D,
 145                 0xB7,0x22,0xD4,0xA0,0xAD,0x23,0x8D,0x25,0xE0,0x17,0x27,0x94,
 146                 0xE3,0xF3,0x5F,0xC8,0x0F,0xB3,0xB8,0xD7,0x96,0xCD,0x42,0xFA,
 147                 0x6C,0x79,0xA2,0x83,
 148                 };
 149         static unsigned char dh2048_g[] = { 0x02, };
 150         DH *dh;
 151         BIGNUM *dhp_bn, *dhg_bn;
 152
 153         if ((dh = DH_new()) == NULL)
 154                 return NULL;
 155         dhp_bn = BN_bin2bn(dh2048_p, sizeof(dh2048_p), NULL);
 156         dhg_bn = BN_bin2bn(dh2048_g, sizeof(dh2048_g), NULL);
 157         if ((dhp_bn == NULL) || (dhg_bn == NULL))
 158         {
 159                 DH_free(dh);
 160                 BN_free(dhp_bn);
 161                 BN_free(dhg_bn);
 162                 return NULL;
 163         }
 164         if (!DH_set0_pqg(dh, dhp_bn, NULL, dhg_bn))
 165         {
 166                 DH_free(dh);
 167                 return NULL;
 168         }
 169         return dh;
 170 }
 171 # endif /* !NO_DH */
 172
 173
 174 /*
 175 **  TLS_RAND_INIT -- initialize STARTTLS random generator
 176 **
 177 **      Parameters:
 178 **              randfile -- name of file with random data
 179 **              logl -- loglevel
 180 **
 181 **      Returns:
 182 **              success/failure
 183 **
 184 **      Side Effects:
 185 **              initializes PRNG for tls library.
 186 */
 187
 188 # define MIN_RAND_BYTES 128     /* 1024 bits */
 189
 190 # define RF_OK          0       /* randfile OK */
 191 # define RF_MISS        1       /* randfile == NULL || *randfile == '\0' */
 192 # define RF_UNKNOWN     2       /* unknown prefix for randfile */
 193
 194 # define RI_NONE        0       /* no init yet */
 195 # define RI_SUCCESS     1       /* init was successful */
 196 # define RI_FAIL        2       /* init failed */
 197
 198 static bool     tls_rand_init __P((char *, int));
 199
 200 static bool
 201 tls_rand_init(randfile, logl)
 202         char *randfile;
 203         int logl;
 204 {
 205 # ifndef HASURANDOMDEV
 206         /* not required if /dev/urandom exists, OpenSSL does it internally */
 207
 208         bool ok;
 209         int randdef;
 210         static int done = RI_NONE;
 211
 212         /*
 213         **  initialize PRNG
 214         */
 215
 216         /* did we try this before? if yes: return old value */
 217         if (done != RI_NONE)
 218                 return done == RI_SUCCESS;
 219
 220         /* set default values */
 221         ok = false;
 222         done = RI_FAIL;
 223         randdef = (randfile == NULL || *randfile == '\0') ? RF_MISS : RF_OK;
 224 #   if EGD
 225         if (randdef == RF_OK && sm_strncasecmp(randfile, "egd:", 4) == 0)
 226         {
 227                 randfile += 4;
 228                 if (RAND_egd(randfile) < 0)
 229                 {
 230                         sm_syslog(LOG_WARNING, NOQID,
 231                                   "STARTTLS: RAND_egd(%s) failed: random number generator not seeded",
 232                                    randfile);
 233                 }
 234                 else
 235                         ok = true;
 236         }
 237         else
 238 #   endif /* EGD */
 239         if (randdef == RF_OK && sm_strncasecmp(randfile, "file:", 5) == 0)
 240         {
 241                 int fd;
 242                 long sff;
 243                 struct stat st;
 244
 245                 randfile += 5;
 246                 sff = SFF_SAFEDIRPATH | SFF_NOWLINK
 247                       | SFF_NOGWFILES | SFF_NOWWFILES
 248                       | SFF_NOGRFILES | SFF_NOWRFILES
 249                       | SFF_MUSTOWN | SFF_ROOTOK | SFF_OPENASROOT;
 250                 if (DontLockReadFiles)
 251                         sff |= SFF_NOLOCK;
 252                 if ((fd = safeopen(randfile, O_RDONLY, 0, sff)) >= 0)
 253                 {
 254                         if (fstat(fd, &st) < 0)
 255                         {
 256                                 if (LogLevel > logl)
 257                                         sm_syslog(LOG_ERR, NOQID,
 258                                                   "STARTTLS: can't fstat(%s)",
 259                                                   randfile);
 260                         }
 261                         else
 262                         {
 263                                 bool use, problem;
 264
 265                                 use = true;
 266                                 problem = false;
 267
 268                                 /* max. age of file: 10 minutes */
 269                                 if (st.st_mtime + 600 < curtime())
 270                                 {
 271                                         use = bitnset(DBS_INSUFFICIENTENTROPY,
 272                                                       DontBlameSendmail);
 273                                         problem = true;
 274                                         if (LogLevel > logl)
 275                                                 sm_syslog(LOG_ERR, NOQID,
 276                                                           "STARTTLS: RandFile %s too old: %s",
 277                                                           randfile,
 278                                                           use ? "unsafe" :
 279                                                                 "unusable");
 280                                 }
 281                                 if (use && st.st_size < MIN_RAND_BYTES)
 282                                 {
 283                                         use = bitnset(DBS_INSUFFICIENTENTROPY,
 284                                                       DontBlameSendmail);
 285                                         problem = true;
 286                                         if (LogLevel > logl)
 287                                                 sm_syslog(LOG_ERR, NOQID,
 288                                                           "STARTTLS: size(%s) < %d: %s",
 289                                                           randfile,
 290                                                           MIN_RAND_BYTES,
 291                                                           use ? "unsafe" :
 292                                                                 "unusable");
 293                                 }
 294                                 if (use)
 295                                         ok = RAND_load_file(randfile, -1) >=
 296                                              MIN_RAND_BYTES;
 297                                 if (use && !ok)
 298                                 {
 299                                         if (LogLevel > logl)
 300                                                 sm_syslog(LOG_WARNING, NOQID,
 301                                                           "STARTTLS: RAND_load_file(%s) failed: random number generator not seeded",
 302                                                           randfile);
 303                                 }
 304                                 if (problem)
 305                                         ok = false;
 306                         }
 307                         if (ok || bitnset(DBS_INSUFFICIENTENTROPY,
 308                                           DontBlameSendmail))
 309                         {
 310                                 /* add this even if fstat() failed */
 311                                 RAND_seed((void *) &st, sizeof(st));
 312                         }
 313                         (void) close(fd);
 314                 }
 315                 else
 316                 {
 317                         if (LogLevel > logl)
 318                                 sm_syslog(LOG_WARNING, NOQID,
 319                                           "STARTTLS: Warning: safeopen(%s) failed",
 320                                           randfile);
 321                 }
 322         }
 323         else if (randdef == RF_OK)
 324         {
 325                 if (LogLevel > logl)
 326                         sm_syslog(LOG_WARNING, NOQID,
 327                                   "STARTTLS: Error: no proper random file definition %s",
 328                                   randfile);
 329                 randdef = RF_UNKNOWN;
 330         }
 331         if (randdef == RF_MISS)
 332         {
 333                 if (LogLevel > logl)
 334                         sm_syslog(LOG_WARNING, NOQID,
 335                                   "STARTTLS: Error: missing random file definition");
 336         }
 337         if (!ok && bitnset(DBS_INSUFFICIENTENTROPY, DontBlameSendmail))
 338         {
 339                 int i;
 340                 long r;
 341                 unsigned char buf[MIN_RAND_BYTES];
 342
 343                 /* assert((MIN_RAND_BYTES % sizeof(long)) == 0); */
 344                 for (i = 0; i <= sizeof(buf) - sizeof(long); i += sizeof(long))
 345                 {
 346                         r = get_random();
 347                         (void) memcpy(buf + i, (void *) &r, sizeof(long));
 348                 }
 349                 RAND_seed(buf, sizeof(buf));
 350                 if (LogLevel > logl)
 351                         sm_syslog(LOG_WARNING, NOQID,
 352                                   "STARTTLS: Warning: random number generator not properly seeded");
 353                 ok = true;
 354         }
 355         done = ok ? RI_SUCCESS : RI_FAIL;
 356         return ok;
 357 # else /* ! HASURANDOMDEV */
 358         return true;
 359 # endif /* ! HASURANDOMDEV */
 360 }
 361 /*
 362 **  INIT_TLS_LIBRARY -- Calls functions which setup TLS library for global use.
 363 **
 364 **      Parameters:
 365 **              fipsmode -- use FIPS?
 366 **
 367 **      Returns:
 368 **              succeeded?
 369 */
 370
 371 bool
 372 init_tls_library(fipsmode)
 373         bool fipsmode;
 374 {
 375         bool bv;
 376
 377         /* basic TLS initialization, ignore result for now */
 378         SSL_library_init();
 379         SSL_load_error_strings();
 380         OpenSSL_add_all_algorithms();
 381 # if 0
 382         /* this is currently a macro for SSL_library_init */
 383         SSLeay_add_ssl_algorithms();
 384 # endif /* 0 */
 385
 386         bv = tls_rand_init(RandFile, 7);
 387 # if _FFR_FIPSMODE
 388         if (bv && fipsmode)
 389         {
 390                 if (!FIPS_mode_set(1))
 391                 {
 392                         unsigned long err;
 393
 394                         err = ERR_get_error();
 395                         if (LogLevel > 0)
 396                                 sm_syslog(LOG_ERR, NOQID,
 397                                         "STARTTLS=init, FIPSMode=%s",
 398                                         ERR_error_string(err, NULL));
 399                         return false;
 400                 }
 401                 else
 402                 {
 403                         if (LogLevel > 9)
 404                                 sm_syslog(LOG_INFO, NOQID,
 405                                         "STARTTLS=init, FIPSMode=ok");
 406                 }
 407         }
 408 #endif /* _FFR_FIPSMODE  */
 409         if (bv && CertFingerprintAlgorithm != NULL)
 410         {
 411                 const EVP_MD *md;
 412
 413                 md = EVP_get_digestbyname(CertFingerprintAlgorithm);
 414                 if (NULL == md)
 415                 {
 416                         bv = false;
 417                         if (LogLevel > 0)
 418                                 sm_syslog(LOG_ERR, NOQID,
 419                                         "STARTTLS=init, CertFingerprintAlgorithm=%s, status=invalid"
 420                                         , CertFingerprintAlgorithm);
 421                 }
 422                 else
 423                         EVP_digest = md;
 424         }
 425         return bv;
 426 }
 427
 428 /*
 429 **  TLS_SET_VERIFY -- request client certificate?
 430 **
 431 **      Parameters:
 432 **              ctx -- TLS context
 433 **              ssl -- TLS structure
 434 **              vrfy -- request certificate?
 435 **
 436 **      Returns:
 437 **              none.
 438 **
 439 **      Side Effects:
 440 **              Sets verification state for TLS
 441 **
 442 # if TLS_VRFY_PER_CTX
 443 **      Notice:
 444 **              This is per TLS context, not per TLS structure;
 445 **              the former is global, the latter per connection.
 446 **              It would be nice to do this per connection, but this
 447 **              doesn't work in the current TLS libraries :-(
 448 # endif * TLS_VRFY_PER_CTX *
 449 */
 450
 451 void
 452 tls_set_verify(ctx, ssl, vrfy)
 453         SSL_CTX *ctx;
 454         SSL *ssl;
 455         bool vrfy;
 456 {
 457 # if !TLS_VRFY_PER_CTX
 458         SSL_set_verify(ssl, vrfy ? SSL_VERIFY_PEER : SSL_VERIFY_NONE, NULL);
 459 # else /* !TLS_VRFY_PER_CTX */
 460         SSL_CTX_set_verify(ctx, vrfy ? SSL_VERIFY_PEER : SSL_VERIFY_NONE,
 461                         NULL);
 462 # endif /* !TLS_VRFY_PER_CTX */
 463 }
 464
 465 /*
 466 **  status in initialization
 467 **  these flags keep track of the status of the initialization
 468 **  i.e., whether a file exists (_EX) and whether it can be used (_OK)
 469 **  [due to permissions]
 470 */
 471
 472 # define TLS_S_NONE     0x00000000      /* none yet */
 473 # define TLS_S_CERT_EX  0x00000001      /* cert file exists */
 474 # define TLS_S_CERT_OK  0x00000002      /* cert file is ok */
 475 # define TLS_S_KEY_EX   0x00000004      /* key file exists */
 476 # define TLS_S_KEY_OK   0x00000008      /* key file is ok */
 477 # define TLS_S_CERTP_EX 0x00000010      /* CA cert path exists */
 478 # define TLS_S_CERTP_OK 0x00000020      /* CA cert path is ok */
 479 # define TLS_S_CERTF_EX 0x00000040      /* CA cert file exists */
 480 # define TLS_S_CERTF_OK 0x00000080      /* CA cert file is ok */
 481 # define TLS_S_CRLF_EX  0x00000100      /* CRL file exists */
 482 # define TLS_S_CRLF_OK  0x00000200      /* CRL file is ok */
 483
 484 # define TLS_S_CERT2_EX 0x00001000      /* 2nd cert file exists */
 485 # define TLS_S_CERT2_OK 0x00002000      /* 2nd cert file is ok */
 486 # define TLS_S_KEY2_EX  0x00004000      /* 2nd key file exists */
 487 # define TLS_S_KEY2_OK  0x00008000      /* 2nd key file is ok */
 488
 489 # define TLS_S_DH_OK    0x00200000      /* DH cert is ok */
 490 # define TLS_S_DHPAR_EX 0x00400000      /* DH param file exists */
 491 # define TLS_S_DHPAR_OK 0x00800000      /* DH param file is ok to use */
 492
 493 /* Type of variable */
 494 # define TLS_T_OTHER    0
 495 # define TLS_T_SRV      1
 496 # define TLS_T_CLT      2
 497
 498 /*
 499 **  TLS_OK_F -- can var be an absolute filename?
 500 **
 501 **      Parameters:
 502 **              var -- filename
 503 **              fn -- what is the filename used for?
 504 **              type -- type of variable
 505 **
 506 **      Returns:
 507 **              ok?
 508 */
 509
 510 static bool
 511 tls_ok_f(var, fn, type)
 512         char *var;
 513         char *fn;
 514         int type;
 515 {
 516         /* must be absolute pathname */
 517         if (var != NULL && *var == '/')
 518                 return true;
 519         if (LogLevel > 12)
 520                 sm_syslog(LOG_WARNING, NOQID, "STARTTLS: %s%s missing",
 521                           type == TLS_T_SRV ? "Server" :
 522                           (type == TLS_T_CLT ? "Client" : ""), fn);
 523         return false;
 524 }
 525 /*
 526 **  TLS_SAFE_F -- is a file safe to use?
 527 **
 528 **      Parameters:
 529 **              var -- filename
 530 **              sff -- flags for safefile()
 531 **              srv -- server side?
 532 **
 533 **      Returns:
 534 **              ok?
 535 */
 536
 537 static bool
 538 tls_safe_f(var, sff, srv)
 539         char *var;
 540         long sff;
 541         bool srv;
 542 {
 543         int ret;
 544
 545         if ((ret = safefile(var, RunAsUid, RunAsGid, RunAsUserName, sff,
 546                             S_IRUSR, NULL)) == 0)
 547                 return true;
 548         if (LogLevel > 7)
 549                 sm_syslog(LOG_WARNING, NOQID, "STARTTLS=%s: file %s unsafe: %s",
 550                           srv ? "server" : "client", var, sm_errstring(ret));
 551         return false;
 552 }
 553
 554 /*
 555 **  TLS_OK_F -- macro to simplify calls to tls_ok_f
 556 **
 557 **      Parameters:
 558 **              var -- filename
 559 **              fn -- what is the filename used for?
 560 **              req -- is the file required?
 561 **              st -- status bit to set if ok
 562 **              type -- type of variable
 563 **
 564 **      Side Effects:
 565 **              uses r, ok; may change ok and status.
 566 **
 567 */
 568
 569 # define TLS_OK_F(var, fn, req, st, type) if (ok) \
 570         { \
 571                 r = tls_ok_f(var, fn, type); \
 572                 if (r) \
 573                         status |= st; \
 574                 else if (req) \
 575                         ok = false; \
 576         }
 577
 578 /*
 579 **  TLS_UNR -- macro to return whether a file should be unreadable
 580 **
 581 **      Parameters:
 582 **              bit -- flag to test
 583 **              req -- flags
 584 **
 585 **      Returns:
 586 **              0/SFF_NORFILES
 587 */
 588 # define TLS_UNR(bit, req)      (bitset(bit, req) ? SFF_NORFILES : 0)
 589 # define TLS_OUNR(bit, req)     (bitset(bit, req) ? SFF_NOWRFILES : 0)
 590 # define TLS_KEYSFF(req)        \
 591         (bitnset(DBS_GROUPREADABLEKEYFILE, DontBlameSendmail) ? \
 592                 TLS_OUNR(TLS_I_KEY_OUNR, req) :                 \
 593                 TLS_UNR(TLS_I_KEY_UNR, req))
 594
 595 /*
 596 **  TLS_SAFE_F -- macro to simplify calls to tls_safe_f
 597 **
 598 **      Parameters:
 599 **              var -- filename
 600 **              sff -- flags for safefile()
 601 **              req -- is the file required?
 602 **              ex -- does the file exist?
 603 **              st -- status bit to set if ok
 604 **              srv -- server side?
 605 **
 606 **      Side Effects:
 607 **              uses r, ok, ex; may change ok and status.
 608 **
 609 */
 610
 611 # define TLS_SAFE_F(var, sff, req, ex, st, srv) if (ex && ok) \
 612         { \
 613                 r = tls_safe_f(var, sff, srv); \
 614                 if (r) \
 615                         status |= st;   \
 616                 else if (req) \
 617                         ok = false;     \
 618         }
 619
 620 # if _FFR_TLS_SE_OPTS
 621 /*
 622 **  LOAD_CERTKEY -- load cert/key for TLS session
 623 **
 624 **      Parameters:
 625 **              ssl -- TLS session context
 626 **              certfile -- filename of certificate
 627 **              keyfile -- filename of private key
 628 **
 629 **      Returns:
 630 **              succeeded?
 631 */
 632
 633 bool
 634 load_certkey(ssl, srv, certfile, keyfile)
 635         SSL *ssl;
 636         bool srv;
 637         char *certfile;
 638         char *keyfile;
 639 {
 640         bool ok;
 641         int r;
 642         long sff, status;
 643         unsigned long req;
 644         char *who;
 645
 646         ok = true;
 647         who = srv ? "server" : "client";
 648         status = TLS_S_NONE;
 649         req = TLS_I_CERT_EX|TLS_I_KEY_EX;
 650         TLS_OK_F(certfile, "CertFile", bitset(TLS_I_CERT_EX, req),
 651                  TLS_S_CERT_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 652         TLS_OK_F(keyfile, "KeyFile", bitset(TLS_I_KEY_EX, req),
 653                  TLS_S_KEY_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 654
 655         /* certfile etc. must be "safe". */
 656         sff = SFF_REGONLY | SFF_SAFEDIRPATH | SFF_NOWLINK
 657              | SFF_NOGWFILES | SFF_NOWWFILES
 658              | SFF_MUSTOWN | SFF_ROOTOK | SFF_OPENASROOT;
 659         if (DontLockReadFiles)
 660                 sff |= SFF_NOLOCK;
 661
 662         TLS_SAFE_F(certfile, sff | TLS_UNR(TLS_I_CERT_UNR, req),
 663                    bitset(TLS_I_CERT_EX, req),
 664                    bitset(TLS_S_CERT_EX, status), TLS_S_CERT_OK, srv);
 665         TLS_SAFE_F(keyfile, sff | TLS_KEYSFF(req),
 666                    bitset(TLS_I_KEY_EX, req),
 667                    bitset(TLS_S_KEY_EX, status), TLS_S_KEY_OK, srv);
 668
 669 # define SSL_use_cert(ssl, certfile) \
 670         SSL_use_certificate_file(ssl, certfile, SSL_FILETYPE_PEM)
 671 # define SSL_USE_CERT "SSL_use_certificate_file"
 672
 673         if (bitset(TLS_S_CERT_OK, status) &&
 674             SSL_use_cert(ssl, certfile) <= 0)
 675         {
 676                 if (LogLevel > 7)
 677                 {
 678                         sm_syslog(LOG_WARNING, NOQID,
 679                                   "STARTTLS=%s, error: %s(%s) failed",
 680                                   who, SSL_USE_CERT, certfile);
 681                         if (LogLevel > 9)
 682                                 tlslogerr(LOG_WARNING, who);
 683                 }
 684                 if (bitset(TLS_I_USE_CERT, req))
 685                         return false;
 686         }
 687         if (bitset(TLS_S_KEY_OK, status) &&
 688             SSL_use_PrivateKey_file(ssl, keyfile, SSL_FILETYPE_PEM) <= 0)
 689         {
 690                 if (LogLevel > 7)
 691                 {
 692                         sm_syslog(LOG_WARNING, NOQID,
 693                                   "STARTTLS=%s, error: SSL_use_PrivateKey_file(%s) failed",
 694                                   who, keyfile);
 695                         if (LogLevel > 9)
 696                                 tlslogerr(LOG_WARNING, who);
 697                 }
 698                 if (bitset(TLS_I_USE_KEY, req))
 699                         return false;
 700         }
 701
 702         /* check the private key */
 703         if (bitset(TLS_S_KEY_OK, status) &&
 704             (r = SSL_check_private_key(ssl)) <= 0)
 705         {
 706                 /* Private key does not match the certificate public key */
 707                 if (LogLevel > 5)
 708                 {
 709                         sm_syslog(LOG_WARNING, NOQID,
 710                                   "STARTTLS=%s, error: SSL_check_private_key failed(%s): %d",
 711                                   who, keyfile, r);
 712                         if (LogLevel > 9)
 713                                 tlslogerr(LOG_WARNING, who);
 714                 }
 715                 if (bitset(TLS_I_USE_KEY, req))
 716                         return false;
 717         }
 718
 719         return true;
 720 }
 721 # endif /* _FFR_TLS_SE_OPTS */
 722
 723 /*
 724 **  INITTLS -- initialize TLS
 725 **
 726 **      Parameters:
 727 **              ctx -- pointer to context
 728 **              req -- requirements for initialization (see sendmail.h)
 729 **              options -- options
 730 **              srv -- server side?
 731 **              certfile -- filename of certificate
 732 **              keyfile -- filename of private key
 733 **              cacertpath -- path to CAs
 734 **              cacertfile -- file with CA(s)
 735 **              dhparam -- parameters for DH
 736 **
 737 **      Returns:
 738 **              succeeded?
 739 */
 740
 741 /*
 742 **  The session_id_context identifies the service that created a session.
 743 **  This information is used to distinguish between multiple TLS-based
 744 **  servers running on the same server. We use the name of the mail system.
 745 **  Note: the session cache is not persistent.
 746 */
 747
 748 static char server_session_id_context[] = "sendmail8";
 749
 750 # if !TLS_NO_RSA
 751 static RSA *
 752 sm_RSA_generate_key(num, e)
 753         int num;
 754         unsigned long e;
 755 {
 756         RSA *rsa = NULL;
 757         BIGNUM *bn_rsa_r4;
 758
 759         bn_rsa_r4 = BN_new();
 760         if ((bn_rsa_r4 != NULL) && BN_set_word(bn_rsa_r4, e) && (rsa = RSA_new()) != NULL)
 761         {
 762                 if (!RSA_generate_key_ex(rsa, num, bn_rsa_r4, NULL))
 763                 {
 764                         RSA_free(rsa);
 765                         rsa = NULL;
 766                 }
 767         }
 768         BN_free(bn_rsa_r4);
 769         return rsa;
 770 }
 771 # endif /* !TLS_NO_RSA */
 772
 773 /* 0.9.8a and b have a problem with SSL_OP_TLS_BLOCK_PADDING_BUG */
 774 #if (OPENSSL_VERSION_NUMBER >= 0x0090800fL)
 775 # define SM_SSL_OP_TLS_BLOCK_PADDING_BUG        1
 776 #else
 777 # define SM_SSL_OP_TLS_BLOCK_PADDING_BUG        0
 778 #endif
 779
 780 bool
 781 inittls(ctx, req, options, srv, certfile, keyfile, cacertpath, cacertfile, dhparam)
 782         SSL_CTX **ctx;
 783         unsigned long req;
 784         unsigned long options;
 785         bool srv;
 786         char *certfile, *keyfile, *cacertpath, *cacertfile, *dhparam;
 787 {
 788 # if !NO_DH
 789         static DH *dh = NULL;
 790 # endif /* !NO_DH */
 791         int r;
 792         bool ok;
 793         long sff, status;
 794         char *who;
 795         char *cf2, *kf2;
 796 # if SM_CONF_SHM
 797         extern int ShmId;
 798 # endif /* SM_CONF_SHM */
 799 # if OPENSSL_VERSION_NUMBER > 0x00907000L
 800         BIO *crl_file;
 801         X509_CRL *crl;
 802         X509_STORE *store;
 803 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */
 804 #if SM_SSL_OP_TLS_BLOCK_PADDING_BUG
 805         long rt_version;
 806         STACK_OF(SSL_COMP) *comp_methods;
 807 #endif
 808
 809         status = TLS_S_NONE;
 810         who = srv ? "server" : "client";
 811         if (ctx == NULL)
 812         {
 813                 syserr("STARTTLS=%s, inittls: ctx == NULL", who);
 814                 /* NOTREACHED */
 815                 SM_ASSERT(ctx != NULL);
 816         }
 817
 818         /* already initialized? (we could re-init...) */
 819         if (*ctx != NULL)
 820                 return true;
 821         ok = true;
 822
 823         /*
 824         **  look for a second filename: it must be separated by a ','
 825         **  no blanks allowed (they won't be skipped).
 826         **  we change a global variable here! this change will be undone
 827         **  before return from the function but only if it returns true.
 828         **  this isn't a problem since in a failure case this function
 829         **  won't be called again with the same (overwritten) values.
 830         **  otherwise each return must be replaced with a goto endinittls.
 831         */
 832
 833         cf2 = NULL;
 834         kf2 = NULL;
 835         if (certfile != NULL && (cf2 = strchr(certfile, ',')) != NULL)
 836         {
 837                 *cf2++ = '\0';
 838                 if (keyfile != NULL && (kf2 = strchr(keyfile, ',')) != NULL)
 839                         *kf2++ = '\0';
 840         }
 841
 842         /*
 843         **  Check whether files/paths are defined
 844         */
 845
 846         TLS_OK_F(certfile, "CertFile", bitset(TLS_I_CERT_EX, req),
 847                  TLS_S_CERT_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 848         TLS_OK_F(keyfile, "KeyFile", bitset(TLS_I_KEY_EX, req),
 849                  TLS_S_KEY_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 850         TLS_OK_F(cacertpath, "CACertPath", bitset(TLS_I_CERTP_EX, req),
 851                  TLS_S_CERTP_EX, TLS_T_OTHER);
 852         TLS_OK_F(cacertfile, "CACertFile", bitset(TLS_I_CERTF_EX, req),
 853                  TLS_S_CERTF_EX, TLS_T_OTHER);
 854
 855 # if OPENSSL_VERSION_NUMBER > 0x00907000L
 856         TLS_OK_F(CRLFile, "CRLFile", bitset(TLS_I_CRLF_EX, req),
 857                  TLS_S_CRLF_EX, TLS_T_OTHER);
 858 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */
 859
 860         /*
 861         **  if the second file is specified it must exist
 862         **  XXX: it is possible here to define only one of those files
 863         */
 864
 865         if (cf2 != NULL)
 866         {
 867                 TLS_OK_F(cf2, "CertFile", bitset(TLS_I_CERT_EX, req),
 868                          TLS_S_CERT2_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 869         }
 870         if (kf2 != NULL)
 871         {
 872                 TLS_OK_F(kf2, "KeyFile", bitset(TLS_I_KEY_EX, req),
 873                          TLS_S_KEY2_EX, srv ? TLS_T_SRV : TLS_T_CLT);
 874         }
 875
 876         /*
 877         **  valid values for dhparam are (only the first char is checked)
 878         **  none        no parameters: don't use DH
 879         **  i           use precomputed 2048 bit parameters
 880         **  512         use precomputed 512 bit parameters
 881         **  1024        generate 1024 bit parameters
 882         **  2048        generate 2048 bit parameters
 883         **  /file/name  read parameters from /file/name
 884         */
 885
 886 #define SET_DH_DFL      \
 887         do {    \
 888                 dhparam = "I";  \
 889                 req |= TLS_I_DHFIXED;   \
 890         } while (0)
 891
 892         if (bitset(TLS_I_TRY_DH, req))
 893         {
 894                 if (dhparam != NULL)
 895                 {
 896                         char c = *dhparam;
 897
 898                         if (c == '1')
 899                                 req |= TLS_I_DH1024;
 900                         else if (c == 'I' || c == 'i')
 901                                 req |= TLS_I_DHFIXED;
 902                         else if (c == '2')
 903                                 req |= TLS_I_DH2048;
 904                         else if (c == '5')
 905                                 req |= TLS_I_DH512;
 906                         else if (c == 'n' || c == 'N')
 907                                 req &= ~TLS_I_TRY_DH;
 908                         else if (c != '/')
 909                         {
 910                                 if (LogLevel > 12)
 911                                         sm_syslog(LOG_WARNING, NOQID,
 912                                                   "STARTTLS=%s, error: illegal value '%s' for DHParameters",
 913                                                   who, dhparam);
 914                                 dhparam = NULL;
 915                         }
 916                 }
 917                 if (dhparam == NULL)
 918                         SET_DH_DFL;
 919                 else if (*dhparam == '/')
 920                 {
 921                         TLS_OK_F(dhparam, "DHParameters",
 922                                  bitset(TLS_I_DHPAR_EX, req),
 923                                  TLS_S_DHPAR_EX, TLS_T_OTHER);
 924                 }
 925         }
 926         if (!ok)
 927                 return ok;
 928
 929         /* certfile etc. must be "safe". */
 930         sff = SFF_REGONLY | SFF_SAFEDIRPATH | SFF_NOWLINK
 931              | SFF_NOGWFILES | SFF_NOWWFILES
 932              | SFF_MUSTOWN | SFF_ROOTOK | SFF_OPENASROOT;
 933         if (DontLockReadFiles)
 934                 sff |= SFF_NOLOCK;
 935
 936         TLS_SAFE_F(certfile, sff | TLS_UNR(TLS_I_CERT_UNR, req),
 937                    bitset(TLS_I_CERT_EX, req),
 938                    bitset(TLS_S_CERT_EX, status), TLS_S_CERT_OK, srv);
 939         TLS_SAFE_F(keyfile, sff | TLS_KEYSFF(req),
 940                    bitset(TLS_I_KEY_EX, req),
 941                    bitset(TLS_S_KEY_EX, status), TLS_S_KEY_OK, srv);
 942         TLS_SAFE_F(cacertfile, sff | TLS_UNR(TLS_I_CERTF_UNR, req),
 943                    bitset(TLS_I_CERTF_EX, req),
 944                    bitset(TLS_S_CERTF_EX, status), TLS_S_CERTF_OK, srv);
 945         if (dhparam != NULL && *dhparam == '/')
 946         {
 947                 TLS_SAFE_F(dhparam, sff | TLS_UNR(TLS_I_DHPAR_UNR, req),
 948                            bitset(TLS_I_DHPAR_EX, req),
 949                            bitset(TLS_S_DHPAR_EX, status), TLS_S_DHPAR_OK, srv);
 950                 if (!bitset(TLS_S_DHPAR_OK, status))
 951                         SET_DH_DFL;
 952         }
 953 # if OPENSSL_VERSION_NUMBER > 0x00907000L
 954         TLS_SAFE_F(CRLFile, sff | TLS_UNR(TLS_I_CRLF_UNR, req),
 955                    bitset(TLS_I_CRLF_EX, req),
 956                    bitset(TLS_S_CRLF_EX, status), TLS_S_CRLF_OK, srv);
 957 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */
 958         if (!ok)
 959                 return ok;
 960         if (cf2 != NULL)
 961         {
 962                 TLS_SAFE_F(cf2, sff | TLS_UNR(TLS_I_CERT_UNR, req),
 963                            bitset(TLS_I_CERT_EX, req),
 964                            bitset(TLS_S_CERT2_EX, status), TLS_S_CERT2_OK, srv);
 965         }
 966         if (kf2 != NULL)
 967         {
 968                 TLS_SAFE_F(kf2, sff | TLS_KEYSFF(req),
 969                            bitset(TLS_I_KEY_EX, req),
 970                            bitset(TLS_S_KEY2_EX, status), TLS_S_KEY2_OK, srv);
 971         }
 972
 973         /* create a method and a new context */
 974         if ((*ctx = SSL_CTX_new(srv ? SSLv23_server_method() :
 975                                       SSLv23_client_method())) == NULL)
 976         {
 977                 if (LogLevel > 7)
 978                         sm_syslog(LOG_WARNING, NOQID,
 979                                   "STARTTLS=%s, error: SSL_CTX_new(SSLv23_%s_method()) failed",
 980                                   who, who);
 981                 if (LogLevel > 9)
 982                         tlslogerr(LOG_WARNING, who);
 983                 return false;
 984         }
 985
 986 # if OPENSSL_VERSION_NUMBER > 0x00907000L
 987         if (CRLFile != NULL)
 988         {
 989                 /* get a pointer to the current certificate validation store */
 990                 store = SSL_CTX_get_cert_store(*ctx);   /* does not fail */
 991                 crl_file = BIO_new(BIO_s_file());
 992                 if (crl_file != NULL)
 993                 {
 994                         if (BIO_read_filename(crl_file, CRLFile) >= 0)
 995                         {
 996                                 crl = PEM_read_bio_X509_CRL(crl_file, NULL,
 997                                                         NULL, NULL);
 998                                 BIO_free(crl_file);
 999                                 X509_STORE_add_crl(store, crl);
1000                                 X509_CRL_free(crl);
1001                                 X509_STORE_set_flags(store,
1002                                         X509_V_FLAG_CRL_CHECK|X509_V_FLAG_CRL_CHECK_ALL);
1003                                 X509_STORE_set_verify_cb_func(store,
1004                                                 x509_verify_cb);
1005                         }
1006                         else
1007                         {
1008                                 if (LogLevel > 9)
1009                                 {
1010                                         sm_syslog(LOG_WARNING, NOQID,
1011                                                   "STARTTLS=%s, error: PEM_read_bio_X509_CRL(%s)=failed",
1012                                                   who, CRLFile);
1013                                 }
1014
1015                                 /* avoid memory leaks */
1016                                 BIO_free(crl_file);
1017                                 return false;
1018                         }
1019
1020                 }
1021                 else if (LogLevel > 9)
1022                         sm_syslog(LOG_WARNING, NOQID,
1023                                   "STARTTLS=%s, error: BIO_new=failed", who);
1024         }
1025         else
1026                 store = NULL;
1027 #  if _FFR_CRLPATH
1028         if (CRLPath != NULL && store != NULL)
1029         {
1030                 X509_LOOKUP *lookup;
1031
1032                 lookup = X509_STORE_add_lookup(store, X509_LOOKUP_hash_dir());
1033                 if (lookup == NULL)
1034                 {
1035                         if (LogLevel > 9)
1036                         {
1037                                 sm_syslog(LOG_WARNING, NOQID,
1038                                           "STARTTLS=%s, error: X509_STORE_add_lookup(hash)=failed",
1039                                           who, CRLFile);
1040                         }
1041                         return false;
1042                 }
1043                 X509_LOOKUP_add_dir(lookup, CRLPath, X509_FILETYPE_PEM);
1044                 X509_STORE_set_flags(store,
1045                         X509_V_FLAG_CRL_CHECK|X509_V_FLAG_CRL_CHECK_ALL);
1046         }
1047 #  endif /* _FFR_CRLPATH */
1048 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */
1049
1050 # if TLS_NO_RSA
1051         /* turn off backward compatibility, required for no-rsa */
1052         SSL_CTX_set_options(*ctx, SSL_OP_NO_SSLv2);
1053 # endif /* TLS_NO_RSA */
1054
1055
1056 # if !TLS_NO_RSA
1057         /*
1058         **  Create a temporary RSA key
1059         **  XXX  Maybe we shouldn't create this always (even though it
1060         **  is only at startup).
1061         **  It is a time-consuming operation and it is not always necessary.
1062         **  maybe we should do it only on demand...
1063         */
1064
1065         if (bitset(TLS_I_RSA_TMP, req)
1066 #  if SM_CONF_SHM
1067             && ShmId != SM_SHM_NO_ID &&
1068             (rsa_tmp = sm_RSA_generate_key(RSA_KEYLENGTH, RSA_F4)) == NULL
1069 #  else /* SM_CONF_SHM */
1070             && 0        /* no shared memory: no need to generate key now */
1071 #  endif /* SM_CONF_SHM */
1072            )
1073         {
1074                 if (LogLevel > 7)
1075                 {
1076                         sm_syslog(LOG_WARNING, NOQID,
1077                                   "STARTTLS=%s, error: RSA_generate_key failed",
1078                                   who);
1079                         if (LogLevel > 9)
1080                                 tlslogerr(LOG_WARNING, who);
1081                 }
1082                 return false;
1083         }
1084 # endif /* !TLS_NO_RSA */
1085
1086         /*
1087         **  load private key
1088         **  XXX change this for DSA-only version
1089         */
1090
1091         if (bitset(TLS_S_KEY_OK, status) &&
1092             SSL_CTX_use_PrivateKey_file(*ctx, keyfile,
1093                                          SSL_FILETYPE_PEM) <= 0)
1094         {
1095                 if (LogLevel > 7)
1096                 {
1097                         sm_syslog(LOG_WARNING, NOQID,
1098                                   "STARTTLS=%s, error: SSL_CTX_use_PrivateKey_file(%s) failed",
1099                                   who, keyfile);
1100                         if (LogLevel > 9)
1101                                 tlslogerr(LOG_WARNING, who);
1102                 }
1103                 if (bitset(TLS_I_USE_KEY, req))
1104                         return false;
1105         }
1106
1107 #if _FFR_TLS_USE_CERTIFICATE_CHAIN_FILE
1108 # define SSL_CTX_use_cert(ssl_ctx, certfile) \
1109         SSL_CTX_use_certificate_chain_file(ssl_ctx, certfile)
1110 # define SSL_CTX_USE_CERT "SSL_CTX_use_certificate_chain_file"
1111 #else
1112 # define SSL_CTX_use_cert(ssl_ctx, certfile) \
1113         SSL_CTX_use_certificate_file(ssl_ctx, certfile, SSL_FILETYPE_PEM)
1114 # define SSL_CTX_USE_CERT "SSL_CTX_use_certificate_file"
1115 #endif
1116
1117         /* get the certificate file */
1118         if (bitset(TLS_S_CERT_OK, status) &&
1119             SSL_CTX_use_cert(*ctx, certfile) <= 0)
1120         {
1121                 if (LogLevel > 7)
1122                 {
1123                         sm_syslog(LOG_WARNING, NOQID,
1124                                   "STARTTLS=%s, error: %s(%s) failed",
1125                                   who, SSL_CTX_USE_CERT, certfile);
1126                         if (LogLevel > 9)
1127                                 tlslogerr(LOG_WARNING, who);
1128                 }
1129                 if (bitset(TLS_I_USE_CERT, req))
1130                         return false;
1131         }
1132
1133         /* check the private key */
1134         if (bitset(TLS_S_KEY_OK, status) &&
1135             (r = SSL_CTX_check_private_key(*ctx)) <= 0)
1136         {
1137                 /* Private key does not match the certificate public key */
1138                 if (LogLevel > 5)
1139                 {
1140                         sm_syslog(LOG_WARNING, NOQID,
1141                                   "STARTTLS=%s, error: SSL_CTX_check_private_key failed(%s): %d",
1142                                   who, keyfile, r);
1143                         if (LogLevel > 9)
1144                                 tlslogerr(LOG_WARNING, who);
1145                 }
1146                 if (bitset(TLS_I_USE_KEY, req))
1147                         return false;
1148         }
1149
1150         /* XXX this code is pretty much duplicated from above! */
1151
1152         /* load private key */
1153         if (bitset(TLS_S_KEY2_OK, status) &&
1154             SSL_CTX_use_PrivateKey_file(*ctx, kf2, SSL_FILETYPE_PEM) <= 0)
1155         {
1156                 if (LogLevel > 7)
1157                 {
1158                         sm_syslog(LOG_WARNING, NOQID,
1159                                   "STARTTLS=%s, error: SSL_CTX_use_PrivateKey_file(%s) failed",
1160                                   who, kf2);
1161                         if (LogLevel > 9)
1162                                 tlslogerr(LOG_WARNING, who);
1163                 }
1164         }
1165
1166         /* get the certificate file */
1167         if (bitset(TLS_S_CERT2_OK, status) &&
1168             SSL_CTX_use_cert(*ctx, cf2) <= 0)
1169         {
1170                 if (LogLevel > 7)
1171                 {
1172                         sm_syslog(LOG_WARNING, NOQID,
1173                                   "STARTTLS=%s, error: %s(%s) failed",
1174                                   who, SSL_CTX_USE_CERT, cf2);
1175                         if (LogLevel > 9)
1176                                 tlslogerr(LOG_WARNING, who);
1177                 }
1178         }
1179
1180         /* also check the private key */
1181         if (bitset(TLS_S_KEY2_OK, status) &&
1182             (r = SSL_CTX_check_private_key(*ctx)) <= 0)
1183         {
1184                 /* Private key does not match the certificate public key */
1185                 if (LogLevel > 5)
1186                 {
1187                         sm_syslog(LOG_WARNING, NOQID,
1188                                   "STARTTLS=%s, error: SSL_CTX_check_private_key 2 failed: %d",
1189                                   who, r);
1190                         if (LogLevel > 9)
1191                                 tlslogerr(LOG_WARNING, who);
1192                 }
1193         }
1194
1195         /* SSL_CTX_set_quiet_shutdown(*ctx, 1); violation of standard? */
1196
1197 #if SM_SSL_OP_TLS_BLOCK_PADDING_BUG
1198
1199         /*
1200         **  In OpenSSL 0.9.8[ab], enabling zlib compression breaks the
1201         **  padding bug work-around, leading to false positives and
1202         **  failed connections. We may not interoperate with systems
1203         **  with the bug, but this is better than breaking on all 0.9.8[ab]
1204         **  systems that have zlib support enabled.
1205         **  Note: this checks the runtime version of the library, not
1206         **  just the compile time version.
1207         */
1208
1209         rt_version = SSLeay();
1210         if (rt_version >= 0x00908000L && rt_version <= 0x0090802fL)
1211         {
1212                 comp_methods = SSL_COMP_get_compression_methods();
1213                 if (comp_methods != NULL && sk_SSL_COMP_num(comp_methods) > 0)
1214                         options &= ~SSL_OP_TLS_BLOCK_PADDING_BUG;
1215         }
1216 #endif
1217         SSL_CTX_set_options(*ctx, (long) options);
1218
1219 # if !NO_DH
1220         /* Diffie-Hellman initialization */
1221         if (bitset(TLS_I_TRY_DH, req))
1222         {
1223 #if _FFR_TLS_EC
1224                 EC_KEY *ecdh;
1225 #endif /* _FFR_TLS_EC */
1226
1227                 if (tTd(96, 8))
1228                         sm_dprintf("inittls: req=%#lx, status=%#lx\n",
1229                                 req, status);
1230                 if (bitset(TLS_S_DHPAR_OK, status))
1231                 {
1232                         BIO *bio;
1233
1234                         if ((bio = BIO_new_file(dhparam, "r")) != NULL)
1235                         {
1236                                 dh = PEM_read_bio_DHparams(bio, NULL, NULL, NULL);
1237                                 BIO_free(bio);
1238                                 if (dh == NULL && LogLevel > 7)
1239                                 {
1240                                         unsigned long err;
1241
1242                                         err = ERR_get_error();
1243                                         sm_syslog(LOG_WARNING, NOQID,
1244                                                   "STARTTLS=%s, error: cannot read DH parameters(%s): %s",
1245                                                   who, dhparam,
1246                                                   ERR_error_string(err, NULL));
1247                                         if (LogLevel > 9)
1248                                                 tlslogerr(LOG_WARNING, who);
1249                                         SET_DH_DFL;
1250                                 }
1251                         }
1252                         else
1253                         {
1254                                 if (LogLevel > 5)
1255                                 {
1256                                         sm_syslog(LOG_WARNING, NOQID,
1257                                                   "STARTTLS=%s, error: BIO_new_file(%s) failed",
1258                                                   who, dhparam);
1259                                         if (LogLevel > 9)
1260                                                 tlslogerr(LOG_WARNING, who);
1261                                 }
1262                         }
1263                 }
1264                 if (dh == NULL && bitset(TLS_I_DH1024|TLS_I_DH2048, req))
1265                 {
1266                         int bits;
1267                         DSA *dsa;
1268
1269                         bits = bitset(TLS_I_DH2048, req) ? 2048 : 1024;
1270                         if (tTd(96, 2))
1271                                 sm_dprintf("inittls: Generating %d bit DH parameters\n", bits);
1272
1273                         dsa = DSA_new();
1274                         /* this takes a while! */
1275                         (void)DSA_generate_parameters_ex(dsa, bits, NULL, 0,
1276                                                          NULL, NULL, NULL);
1277                         dh = DSA_dup_DH(dsa);
1278                         DSA_free(dsa);
1279                 }
1280                 else if (dh == NULL && bitset(TLS_I_DHFIXED, req))
1281                 {
1282                         if (tTd(96, 2))
1283                                 sm_dprintf("inittls: Using precomputed 2048 bit DH parameters\n");
1284                         dh = get_dh2048();
1285                 }
1286                 else if (dh == NULL && bitset(TLS_I_DH512, req))
1287                 {
1288                         if (tTd(96, 2))
1289                                 sm_dprintf("inittls: Using precomputed 512 bit DH parameters\n");
1290                         dh = get_dh512();
1291                 }
1292
1293                 if (dh == NULL)
1294                 {
1295                         if (LogLevel > 9)
1296                         {
1297                                 unsigned long err;
1298
1299                                 err = ERR_get_error();
1300                                 sm_syslog(LOG_WARNING, NOQID,
1301                                           "STARTTLS=%s, error: cannot read or set DH parameters(%s): %s",
1302                                           who, dhparam,
1303                                           ERR_error_string(err, NULL));
1304                         }
1305                         if (bitset(TLS_I_REQ_DH, req))
1306                                 return false;
1307                 }
1308                 else
1309                 {
1310                         /* important to avoid small subgroup attacks */
1311                         SSL_CTX_set_options(*ctx, SSL_OP_SINGLE_DH_USE);
1312
1313                         SSL_CTX_set_tmp_dh(*ctx, dh);
1314                         if (LogLevel > 13)
1315                                 sm_syslog(LOG_INFO, NOQID,
1316                                           "STARTTLS=%s, Diffie-Hellman init, key=%d bit (%c)",
1317                                           who, 8 * DH_size(dh), *dhparam);
1318                         DH_free(dh);
1319                 }
1320
1321 #if _FFR_TLS_EC
1322                 ecdh = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1);
1323                 if (ecdh != NULL)
1324                 {
1325                         SSL_CTX_set_options(*ctx, SSL_OP_SINGLE_ECDH_USE);
1326                         SSL_CTX_set_tmp_ecdh(*ctx, ecdh);
1327                         EC_KEY_free(ecdh);
1328                 }
1329 #endif /* _FFR_TLS_EC */
1330
1331         }
1332 # endif /* !NO_DH */
1333
1334
1335         /* XXX do we need this cache here? */
1336         if (bitset(TLS_I_CACHE, req))
1337         {
1338                 SSL_CTX_sess_set_cache_size(*ctx, 1);
1339                 SSL_CTX_set_timeout(*ctx, 1);
1340                 SSL_CTX_set_session_id_context(*ctx,
1341                         (void *) &server_session_id_context,
1342                         sizeof(server_session_id_context));
1343                 (void) SSL_CTX_set_session_cache_mode(*ctx,
1344                                 SSL_SESS_CACHE_SERVER);
1345         }
1346         else
1347         {
1348                 (void) SSL_CTX_set_session_cache_mode(*ctx,
1349                                 SSL_SESS_CACHE_OFF);
1350         }
1351
1352         /* load certificate locations and default CA paths */
1353         if (bitset(TLS_S_CERTP_EX, status) && bitset(TLS_S_CERTF_EX, status))
1354         {
1355                 if ((r = SSL_CTX_load_verify_locations(*ctx, cacertfile,
1356                                                        cacertpath)) == 1)
1357                 {
1358 # if !TLS_NO_RSA
1359                         if (bitset(TLS_I_RSA_TMP, req))
1360                                 SSL_CTX_set_tmp_rsa_callback(*ctx, tmp_rsa_key);
1361 # endif /* !TLS_NO_RSA */
1362
1363                         /*
1364                         **  We have to install our own verify callback:
1365                         **  SSL_VERIFY_PEER requests a client cert but even
1366                         **  though *FAIL_IF* isn't set, the connection
1367                         **  will be aborted if the client presents a cert
1368                         **  that is not "liked" (can't be verified?) by
1369                         **  the TLS library :-(
1370                         */
1371
1372                         /*
1373                         **  XXX currently we could call tls_set_verify()
1374                         **  but we hope that that function will later on
1375                         **  only set the mode per connection.
1376                         */
1377                         SSL_CTX_set_verify(*ctx,
1378                                 bitset(TLS_I_NO_VRFY, req) ? SSL_VERIFY_NONE
1379                                                            : SSL_VERIFY_PEER,
1380                                 NULL);
1381
1382                         /* install verify callback */
1383                         SSL_CTX_set_cert_verify_callback(*ctx, tls_verify_cb,
1384                                                          NULL);
1385                         SSL_CTX_set_client_CA_list(*ctx,
1386                                 SSL_load_client_CA_file(cacertfile));
1387                 }
1388                 else
1389                 {
1390                         /*
1391                         **  can't load CA data; do we care?
1392                         **  the data is necessary to authenticate the client,
1393                         **  which in turn would be necessary
1394                         **  if we want to allow relaying based on it.
1395                         */
1396                         if (LogLevel > 5)
1397                         {
1398                                 sm_syslog(LOG_WARNING, NOQID,
1399                                           "STARTTLS=%s, error: load verify locs %s, %s failed: %d",
1400                                           who, cacertpath, cacertfile, r);
1401                                 if (LogLevel > 9)
1402                                         tlslogerr(LOG_WARNING, who);
1403                         }
1404                         if (bitset(TLS_I_VRFY_LOC, req))
1405                                 return false;
1406                 }
1407         }
1408
1409         /* XXX: make this dependent on an option? */
1410         if (tTd(96, 9))
1411                 SSL_CTX_set_info_callback(*ctx, apps_ssl_info_cb);
1412
1413         /* install our own cipher list */
1414         if (CipherList != NULL && *CipherList != '\0')
1415         {
1416                 if (SSL_CTX_set_cipher_list(*ctx, CipherList) <= 0)
1417                 {
1418                         if (LogLevel > 7)
1419                         {
1420                                 sm_syslog(LOG_WARNING, NOQID,
1421                                           "STARTTLS=%s, error: SSL_CTX_set_cipher_list(%s) failed, list ignored",
1422                                           who, CipherList);
1423
1424                                 if (LogLevel > 9)
1425                                         tlslogerr(LOG_WARNING, who);
1426                         }
1427                         /* failure if setting to this list is required? */
1428                 }
1429         }
1430
1431         if (LogLevel > 12)
1432                 sm_syslog(LOG_INFO, NOQID, "STARTTLS=%s, init=%d", who, ok);
1433
1434 # if 0
1435         /*
1436         **  this label is required if we want to have a "clean" exit
1437         **  see the comments above at the initialization of cf2
1438         */
1439
1440     endinittls:
1441 # endif /* 0 */
1442
1443         /* undo damage to global variables */
1444         if (cf2 != NULL)
1445                 *--cf2 = ',';
1446         if (kf2 != NULL)
1447                 *--kf2 = ',';
1448
1449         return ok;
1450 }
1451
1452 /*
1453 **  CERT_FP -- get cert fingerprint
1454 **
1455 **      Parameters:
1456 **              cert -- TLS cert
1457 **              mac -- macro storage
1458 **              macro -- where to store cert fp
1459 **
1460 **      Returns:
1461 **              <=0: cert fp calculation failed
1462 **              >0: cert fp calculation ok
1463 */
1464
1465 static int
1466 cert_fp(cert, evp_digest, mac, macro)
1467         X509 *cert;
1468         const EVP_MD *evp_digest;
1469         MACROS_T *mac;
1470         char *macro;
1471 {
1472         unsigned int n;
1473         int r;
1474         unsigned char md[EVP_MAX_MD_SIZE];
1475         char md5h[EVP_MAX_MD_SIZE * 3];
1476         static const char hexcodes[] = "0123456789ABCDEF";
1477
1478         n = 0;
1479         if (X509_digest(cert, EVP_digest, md, &n) == 0 || n <= 0)
1480         {
1481                 macdefine(mac, A_TEMP, macid(macro), "");
1482                 return 0;
1483         }
1484
1485         SM_ASSERT((n * 3) + 2 < sizeof(md5h));
1486         for (r = 0; r < (int) n; r++)
1487         {
1488                 md5h[r * 3] = hexcodes[(md[r] & 0xf0) >> 4];
1489                 md5h[(r * 3) + 1] = hexcodes[(md[r] & 0x0f)];
1490                 md5h[(r * 3) + 2] = ':';
1491         }
1492         md5h[(n * 3) - 1] = '\0';
1493         macdefine(mac, A_TEMP, macid(macro), md5h);
1494         return 1;
1495 }
1496
1497 /*
1498 **  TLS_GET_INFO -- get information about TLS connection
1499 **
1500 **      Parameters:
1501 **              ssl -- TLS connection structure
1502 **              srv -- server or client
1503 **              host -- hostname of other side
1504 **              mac -- macro storage
1505 **              certreq -- did we ask for a cert?
1506 **
1507 **      Returns:
1508 **              result of authentication.
1509 **
1510 **      Side Effects:
1511 **              sets various TLS related macros.
1512 */
1513
1514 int
1515 tls_get_info(ssl, srv, host, mac, certreq)
1516         SSL *ssl;
1517         bool srv;
1518         char *host;
1519         MACROS_T *mac;
1520         bool certreq;
1521 {
1522         const SSL_CIPHER *c;
1523         int b, r;
1524         long verifyok;
1525         char *s, *who;
1526         char bitstr[16];
1527         X509 *cert;
1528
1529         c = SSL_get_current_cipher(ssl);
1530
1531         /* cast is just workaround for compiler warning */
1532         macdefine(mac, A_TEMP, macid("{cipher}"),
1533                   (char *) SSL_CIPHER_get_name(c));
1534         b = SSL_CIPHER_get_bits(c, &r);
1535         (void) sm_snprintf(bitstr, sizeof(bitstr), "%d", b);
1536         macdefine(mac, A_TEMP, macid("{cipher_bits}"), bitstr);
1537         (void) sm_snprintf(bitstr, sizeof(bitstr), "%d", r);
1538         macdefine(mac, A_TEMP, macid("{alg_bits}"), bitstr);
1539         s = (char *) SSL_get_version(ssl);
1540         if (s == NULL)
1541                 s = "UNKNOWN";
1542         macdefine(mac, A_TEMP, macid("{tls_version}"), s);
1543
1544         who = srv ? "server" : "client";
1545         cert = SSL_get_peer_certificate(ssl);
1546         verifyok = SSL_get_verify_result(ssl);
1547         if (LogLevel > 14)
1548                 sm_syslog(LOG_INFO, NOQID,
1549                           "STARTTLS=%s, get_verify: %ld get_peer: 0x%lx",
1550                           who, verifyok, (unsigned long) cert);
1551         if (cert != NULL)
1552         {
1553                 X509_NAME *subj, *issuer;
1554                 char buf[MAXNAME];
1555
1556                 subj = X509_get_subject_name(cert);
1557                 issuer = X509_get_issuer_name(cert);
1558                 X509_NAME_oneline(subj, buf, sizeof(buf));
1559                 macdefine(mac, A_TEMP, macid("{cert_subject}"),
1560                          xtextify(buf, "<>\")"));
1561                 X509_NAME_oneline(issuer, buf, sizeof(buf));
1562                 macdefine(mac, A_TEMP, macid("{cert_issuer}"),
1563                          xtextify(buf, "<>\")"));
1564
1565 # define LL_BADCERT     8
1566
1567 #define CERTFPMACRO (CertFingerprintAlgorithm != NULL ? "{cert_fp}" : "{cert_md5}")
1568
1569 #define CHECK_X509_NAME(which)  \
1570         do {    \
1571                 if (r == -1)    \
1572                 {               \
1573                         sm_strlcpy(buf, "BadCertificateUnknown", sizeof(buf)); \
1574                         if (LogLevel > LL_BADCERT)      \
1575                                 sm_syslog(LOG_INFO, NOQID,      \
1576                                         "STARTTLS=%s, relay=%.100s, field=%s, status=failed to extract CN",     \
1577                                         who,    \
1578                                         host == NULL ? "local" : host,  \
1579                                         which); \
1580                 }               \
1581                 else if ((size_t)r >= sizeof(buf) - 1)  \
1582                 {               \
1583                         sm_strlcpy(buf, "BadCertificateTooLong", sizeof(buf)); \
1584                         if (LogLevel > 7)       \
1585                                 sm_syslog(LOG_INFO, NOQID,      \
1586                                         "STARTTLS=%s, relay=%.100s, field=%s, status=CN too long",      \
1587                                         who,    \
1588                                         host == NULL ? "local" : host,  \
1589                                         which); \
1590                 }               \
1591                 else if ((size_t)r > strlen(buf))       \
1592                 {               \
1593                         sm_strlcpy(buf, "BadCertificateContainsNUL",    \
1594                                 sizeof(buf));   \
1595                         if (LogLevel > 7)       \
1596                                 sm_syslog(LOG_INFO, NOQID,      \
1597                                         "STARTTLS=%s, relay=%.100s, field=%s, status=CN contains NUL",  \
1598                                         who,    \
1599                                         host == NULL ? "local" : host,  \
1600                                         which); \
1601                 }               \
1602         } while (0)
1603
1604                 r = X509_NAME_get_text_by_NID(subj, NID_commonName, buf,
1605                         sizeof buf);
1606                 CHECK_X509_NAME("cn_subject");
1607                 macdefine(mac, A_TEMP, macid("{cn_subject}"),
1608                          xtextify(buf, "<>\")"));
1609                 r = X509_NAME_get_text_by_NID(issuer, NID_commonName, buf,
1610                         sizeof buf);
1611                 CHECK_X509_NAME("cn_issuer");
1612                 macdefine(mac, A_TEMP, macid("{cn_issuer}"),
1613                          xtextify(buf, "<>\")"));
1614                 (void) cert_fp(cert, EVP_digest, mac, CERTFPMACRO);
1615         }
1616         else
1617         {
1618                 macdefine(mac, A_PERM, macid("{cert_subject}"), "");
1619                 macdefine(mac, A_PERM, macid("{cert_issuer}"), "");
1620                 macdefine(mac, A_PERM, macid("{cn_subject}"), "");
1621                 macdefine(mac, A_PERM, macid("{cn_issuer}"), "");
1622                 macdefine(mac, A_TEMP, macid(CERTFPMACRO), "");
1623         }
1624         switch (verifyok)
1625         {
1626           case X509_V_OK:
1627                 if (cert != NULL)
1628                 {
1629                         s = "OK";
1630                         r = TLS_AUTH_OK;
1631                 }
1632                 else
1633                 {
1634                         s = certreq ? "NO" : "NOT",
1635                         r = TLS_AUTH_NO;
1636                 }
1637                 break;
1638           default:
1639                 s = "FAIL";
1640                 r = TLS_AUTH_FAIL;
1641                 break;
1642         }
1643         macdefine(mac, A_PERM, macid("{verify}"), s);
1644         if (cert != NULL)
1645                 X509_free(cert);
1646
1647         /* do some logging */
1648         if (LogLevel > 8)
1649         {
1650                 char *vers, *s1, *s2, *cbits, *algbits;
1651
1652                 vers = macget(mac, macid("{tls_version}"));
1653                 cbits = macget(mac, macid("{cipher_bits}"));
1654                 algbits = macget(mac, macid("{alg_bits}"));
1655                 s1 = macget(mac, macid("{verify}"));
1656                 s2 = macget(mac, macid("{cipher}"));
1657
1658                 /* XXX: maybe cut off ident info? */
1659                 sm_syslog(LOG_INFO, NOQID,
1660                           "STARTTLS=%s, relay=%.100s, version=%.16s, verify=%.16s, cipher=%.64s, bits=%.6s/%.6s",
1661                           who,
1662                           host == NULL ? "local" : host,
1663                           vers, s1, s2, /* sm_snprintf() can deal with NULL */
1664                           algbits == NULL ? "0" : algbits,
1665                           cbits == NULL ? "0" : cbits);
1666                 if (LogLevel > 11)
1667                 {
1668                         /*
1669                         **  Maybe run xuntextify on the strings?
1670                         **  That is easier to read but makes it maybe a bit
1671                         **  more complicated to figure out the right values
1672                         **  for the access map...
1673                         */
1674
1675                         s1 = macget(mac, macid("{cert_subject}"));
1676                         s2 = macget(mac, macid("{cert_issuer}"));
1677                         sm_syslog(LOG_INFO, NOQID,
1678                                   "STARTTLS=%s, cert-subject=%.256s, cert-issuer=%.256s, verifymsg=%s",
1679                                   who, s1, s2,
1680                                   X509_verify_cert_error_string(verifyok));
1681                 }
1682         }
1683         return r;
1684 }
1685 /*
1686 **  ENDTLS -- shutdown secure connection
1687 **
1688 **      Parameters:
1689 **              ssl -- SSL connection information.
1690 **              side -- server/client (for logging).
1691 **
1692 **      Returns:
1693 **              success? (EX_* code)
1694 */
1695
1696 int
1697 endtls(ssl, side)
1698         SSL *ssl;
1699         char *side;
1700 {
1701         int ret = EX_OK;
1702
1703         if (ssl != NULL)
1704         {
1705                 int r;
1706
1707                 if ((r = SSL_shutdown(ssl)) < 0)
1708                 {
1709                         if (LogLevel > 11)
1710                         {
1711                                 sm_syslog(LOG_WARNING, NOQID,
1712                                           "STARTTLS=%s, SSL_shutdown failed: %d",
1713                                           side, r);
1714                                 tlslogerr(LOG_WARNING, side);
1715                         }
1716                         ret = EX_SOFTWARE;
1717                 }
1718 # if !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER > 0x0090602fL
1719
1720                 /*
1721                 **  Bug in OpenSSL (at least up to 0.9.6b):
1722                 **  From: Lutz.Jaenicke@aet.TU-Cottbus.DE
1723                 **  Message-ID: <20010723152244.A13122@serv01.aet.tu-cottbus.de>
1724                 **  To: openssl-users@openssl.org
1725                 **  Subject: Re: SSL_shutdown() woes (fwd)
1726                 **
1727                 **  The side sending the shutdown alert first will
1728                 **  not care about the answer of the peer but will
1729                 **  immediately return with a return value of "0"
1730                 **  (ssl/s3_lib.c:ssl3_shutdown()). SSL_get_error will evaluate
1731                 **  the value of "0" and as the shutdown alert of the peer was
1732                 **  not received (actually, the program did not even wait for
1733                 **  the answer), an SSL_ERROR_SYSCALL is flagged, because this
1734                 **  is the default rule in case everything else does not apply.
1735                 **
1736                 **  For your server the problem is different, because it
1737                 **  receives the shutdown first (setting SSL_RECEIVED_SHUTDOWN),
1738                 **  then sends its response (SSL_SENT_SHUTDOWN), so for the
1739                 **  server the shutdown was successfull.
1740                 **
1741                 **  As is by know, you would have to call SSL_shutdown() once
1742                 **  and ignore an SSL_ERROR_SYSCALL returned. Then call
1743                 **  SSL_shutdown() again to actually get the server's response.
1744                 **
1745                 **  In the last discussion, Bodo Moeller concluded that a
1746                 **  rewrite of the shutdown code would be necessary, but
1747                 **  probably with another API, as the change would not be
1748                 **  compatible to the way it is now.  Things do not become
1749                 **  easier as other programs do not follow the shutdown
1750                 **  guidelines anyway, so that a lot error conditions and
1751                 **  compitibility issues would have to be caught.
1752                 **
1753                 **  For now the recommondation is to ignore the error message.
1754                 */
1755
1756                 else if (r == 0)
1757                 {
1758                         if (LogLevel > 15)
1759                         {
1760                                 sm_syslog(LOG_WARNING, NOQID,
1761                                           "STARTTLS=%s, SSL_shutdown not done",
1762                                           side);
1763                                 tlslogerr(LOG_WARNING, side);
1764                         }
1765                         ret = EX_SOFTWARE;
1766                 }
1767 # endif /* !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER > 0x0090602fL */
1768                 SSL_free(ssl);
1769                 ssl = NULL;
1770         }
1771         return ret;
1772 }
1773
1774 # if !TLS_NO_RSA
1775 /*
1776 **  TMP_RSA_KEY -- return temporary RSA key
1777 **
1778 **      Parameters:
1779 **              s -- TLS connection structure
1780 **              export --
1781 **              keylength --
1782 **
1783 **      Returns:
1784 **              temporary RSA key.
1785 */
1786
1787 #   ifndef MAX_RSA_TMP_CNT
1788 #    define MAX_RSA_TMP_CNT     1000    /* XXX better value? */
1789 #   endif /* ! MAX_RSA_TMP_CNT */
1790
1791 /* ARGUSED0 */
1792 static RSA *
1793 tmp_rsa_key(s, export, keylength)
1794         SSL *s;
1795         int export;
1796         int keylength;
1797 {
1798 #   if SM_CONF_SHM
1799         extern int ShmId;
1800         extern int *PRSATmpCnt;
1801
1802         if (ShmId != SM_SHM_NO_ID && rsa_tmp != NULL &&
1803             ++(*PRSATmpCnt) < MAX_RSA_TMP_CNT)
1804                 return rsa_tmp;
1805 #   endif /* SM_CONF_SHM */
1806
1807         if (rsa_tmp != NULL)
1808                 RSA_free(rsa_tmp);
1809         rsa_tmp = sm_RSA_generate_key(RSA_KEYLENGTH, RSA_F4);
1810         if (rsa_tmp == NULL)
1811         {
1812                 if (LogLevel > 0)
1813                         sm_syslog(LOG_ERR, NOQID,
1814                                   "STARTTLS=server, tmp_rsa_key: RSA_generate_key failed!");
1815         }
1816         else
1817         {
1818 #   if SM_CONF_SHM
1819 #    if 0
1820                 /*
1821                 **  XXX we can't (yet) share the new key...
1822                 **      The RSA structure contains pointers hence it can't be
1823                 **      easily kept in shared memory.  It must be transformed
1824                 **      into a continous memory region first, then stored,
1825                 **      and later read out again (each time re-transformed).
1826                 */
1827
1828                 if (ShmId != SM_SHM_NO_ID)
1829                         *PRSATmpCnt = 0;
1830 #    endif /* 0 */
1831 #   endif /* SM_CONF_SHM */
1832                 if (LogLevel > 9)
1833                         sm_syslog(LOG_ERR, NOQID,
1834                                   "STARTTLS=server, tmp_rsa_key: new temp RSA key");
1835         }
1836         return rsa_tmp;
1837 }
1838 # endif /* !TLS_NO_RSA */
1839 /*
1840 **  APPS_SSL_INFO_CB -- info callback for TLS connections
1841 **
1842 **      Parameters:
1843 **              s -- TLS connection structure
1844 **              where -- state in handshake
1845 **              ret -- return code of last operation
1846 **
1847 **      Returns:
1848 **              none.
1849 */
1850
1851 static void
1852 apps_ssl_info_cb(s, where, ret)
1853         CONST097 SSL *s;
1854         int where;
1855         int ret;
1856 {
1857         int w;
1858         char *str;
1859         BIO *bio_err = NULL;
1860
1861         if (LogLevel > 14)
1862                 sm_syslog(LOG_INFO, NOQID,
1863                           "STARTTLS: info_callback where=0x%x, ret=%d",
1864                           where, ret);
1865
1866         w = where & ~SSL_ST_MASK;
1867         if (bio_err == NULL)
1868                 bio_err = BIO_new_fp(stderr, BIO_NOCLOSE);
1869
1870         if (bitset(SSL_ST_CONNECT, w))
1871                 str = "SSL_connect";
1872         else if (bitset(SSL_ST_ACCEPT, w))
1873                 str = "SSL_accept";
1874         else
1875                 str = "undefined";
1876
1877         if (bitset(SSL_CB_LOOP, where))
1878         {
1879                 if (LogLevel > 12)
1880                         sm_syslog(LOG_NOTICE, NOQID,
1881                                 "STARTTLS: %s:%s",
1882                                 str, SSL_state_string_long(s));
1883         }
1884         else if (bitset(SSL_CB_ALERT, where))
1885         {
1886                 str = bitset(SSL_CB_READ, where) ? "read" : "write";
1887                 if (LogLevel > 12)
1888                         sm_syslog(LOG_NOTICE, NOQID,
1889                                 "STARTTLS: SSL3 alert %s:%s:%s",
1890                                 str, SSL_alert_type_string_long(ret),
1891                                 SSL_alert_desc_string_long(ret));
1892         }
1893         else if (bitset(SSL_CB_EXIT, where))
1894         {
1895                 if (ret == 0)
1896                 {
1897                         if (LogLevel > 7)
1898                                 sm_syslog(LOG_WARNING, NOQID,
1899                                         "STARTTLS: %s:failed in %s",
1900                                         str, SSL_state_string_long(s));
1901                 }
1902                 else if (ret < 0)
1903                 {
1904                         if (LogLevel > 7)
1905                                 sm_syslog(LOG_WARNING, NOQID,
1906                                         "STARTTLS: %s:error in %s",
1907                                         str, SSL_state_string_long(s));
1908                 }
1909         }
1910 }
1911 /*
1912 **  TLS_VERIFY_LOG -- log verify error for TLS certificates
1913 **
1914 **      Parameters:
1915 **              ok -- verify ok?
1916 **              ctx -- x509 context
1917 **              name -- from where is this called?
1918 **
1919 **      Returns:
1920 **              1 -- ok
1921 */
1922
1923 static int
1924 tls_verify_log(ok, ctx, name)
1925         int ok;
1926         X509_STORE_CTX *ctx;
1927         const char *name;
1928 {
1929         X509 *cert;
1930         int reason, depth;
1931         char buf[512];
1932
1933         cert = X509_STORE_CTX_get_current_cert(ctx);
1934         reason = X509_STORE_CTX_get_error(ctx);
1935         depth = X509_STORE_CTX_get_error_depth(ctx);
1936         X509_NAME_oneline(X509_get_subject_name(cert), buf, sizeof(buf));
1937         sm_syslog(LOG_INFO, NOQID,
1938                   "STARTTLS: %s cert verify: depth=%d %s, state=%d, reason=%s",
1939                   name, depth, buf, ok, X509_verify_cert_error_string(reason));
1940         return 1;
1941 }
1942
1943 /*
1944 **  TLS_VERIFY_CB -- verify callback for TLS certificates
1945 **
1946 **      Parameters:
1947 **              ctx -- x509 context
1948 **
1949 **      Returns:
1950 **              accept connection?
1951 **              currently: always yes.
1952 */
1953
1954 static int
1955 #  if !defined(OPENSSL_VERSION_NUMBER) || OPENSSL_VERSION_NUMBER < 0x00907000L
1956 tls_verify_cb(ctx)
1957         X509_STORE_CTX *ctx;
1958 #  else /* !defined() || OPENSSL_VERSION_NUMBER < 0x00907000L */
1959 tls_verify_cb(ctx, unused)
1960         X509_STORE_CTX *ctx;
1961         void *unused;
1962 #  endif /* !defined() || OPENSSL_VERSION_NUMBER < 0x00907000L */
1963 {
1964         int ok;
1965
1966         /*
1967         **  man SSL_CTX_set_cert_verify_callback():
1968         **  callback should return 1 to indicate verification success
1969         **  and 0 to indicate verification failure.
1970         */
1971
1972         ok = X509_verify_cert(ctx);
1973         if (ok <= 0)
1974         {
1975                 if (LogLevel > 13)
1976                         return tls_verify_log(ok, ctx, "TLS");
1977         }
1978         return 1;
1979 }
1980 /*
1981 **  TLSLOGERR -- log the errors from the TLS error stack
1982 **
1983 **      Parameters:
1984 **              level -- syslog level
1985 **              who -- server/client (for logging).
1986 **
1987 **      Returns:
1988 **              none.
1989 */
1990
1991 void
1992 tlslogerr(level, who)
1993         int level;
1994         const char *who;
1995 {
1996         unsigned long l;
1997         int line, flags;
1998         unsigned long es;
1999         char *file, *data;
2000         char buf[256];
2001
2002         es = CRYPTO_thread_id();
2003         while ((l = ERR_get_error_line_data((const char **) &file, &line,
2004                                             (const char **) &data, &flags))
2005                 != 0)
2006         {
2007                 sm_syslog(level, NOQID,
2008                           "STARTTLS=%s: %lu:%s:%s:%d:%s", who, es,
2009                           ERR_error_string(l, buf),
2010                           file, line,
2011                           bitset(ERR_TXT_STRING, flags) ? data : "");
2012         }
2013 }
2014
2015 # if OPENSSL_VERSION_NUMBER > 0x00907000L
2016 /*
2017 **  X509_VERIFY_CB -- verify callback
2018 **
2019 **      Parameters:
2020 **              ctx -- x509 context
2021 **
2022 **      Returns:
2023 **              accept connection?
2024 **              currently: always yes.
2025 */
2026
2027 static int
2028 x509_verify_cb(ok, ctx)
2029         int ok;
2030         X509_STORE_CTX *ctx;
2031 {
2032         if (ok == 0)
2033         {
2034                 if (LogLevel > 13)
2035                         tls_verify_log(ok, ctx, "x509");
2036                 if (X509_STORE_CTX_get_error(ctx) == X509_V_ERR_UNABLE_TO_GET_CRL)
2037                 {
2038                         X509_STORE_CTX_set_error(ctx, 0);
2039                         return 1;       /* override it */
2040                 }
2041         }
2042         return ok;
2043 }
2044 # endif /* OPENSSL_VERSION_NUMBER > 0x00907000L */
2045 #endif /* STARTTLS */