src/ngircd/conn-ssl.c

   1 /*
   2  * ngIRCd -- The Next Generation IRC Daemon
   3  * Copyright (c)2005-2008 Florian Westphal (fw@strlen.de).
   4  * Copyright (c)2008-2014 Alexander Barton (alex@barton.de) and Contributors.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  * Please read the file COPYING, README and AUTHORS for more information.
  11  */
  12
  13 #include "portab.h"
  14
  15 /**
  16  * @file
  17  * SSL wrapper functions
  18  */
  19
  20 #include "conf-ssl.h"
  21
  22 #ifdef SSL_SUPPORT
  23
  24 #include "io.h"
  25 #include <assert.h>
  26 #include <stdio.h>
  27 #include <string.h>
  28 #include <stdlib.h>
  29 #include <errno.h>
  30
  31 #define CONN_MODULE
  32 #include "conn.h"
  33 #include "conf.h"
  34 #include "conn-func.h"
  35 #include "conn-ssl.h"
  36 #include "log.h"
  37
  38 #include "defines.h"
  39
  40 extern struct SSLOptions Conf_SSLOptions;
  41
  42 #ifdef HAVE_LIBSSL
  43 #include <openssl/err.h>
  44 #include <openssl/rand.h>
  45 #include <openssl/dh.h>
  46 #include <openssl/x509v3.h>
  47
  48 #define MAX_CERT_CHAIN_LENGTH   10      /* XXX: do not hardcode */
  49
  50 static SSL_CTX * ssl_ctx;
  51 static DH *dh_params;
  52
  53 static bool ConnSSL_LoadServerKey_openssl PARAMS(( SSL_CTX *c ));
  54 static bool ConnSSL_SetVerifyProperties_openssl PARAMS((SSL_CTX * c));
  55 #endif
  56
  57 #ifdef HAVE_LIBGNUTLS
  58 #include <sys/types.h>
  59 #include <sys/stat.h>
  60 #include <fcntl.h>
  61 #include <unistd.h>
  62 #include <gnutls/x509.h>
  63
  64 #define DH_BITS 2048
  65 #define DH_BITS_MIN 1024
  66
  67 #define MAX_HASH_SIZE   64      /* from gnutls-int.h */
  68
  69 typedef struct {
  70         int refcnt;
  71         gnutls_certificate_credentials_t x509_cred;
  72         gnutls_dh_params_t dh_params;
  73 } x509_cred_slot;
  74
  75 static array x509_creds = INIT_ARRAY;
  76 static size_t x509_cred_idx;
  77
  78 static gnutls_dh_params_t dh_params;
  79 static gnutls_priority_t priorities_cache = NULL;
  80 static bool ConnSSL_LoadServerKey_gnutls PARAMS(( void ));
  81 static bool ConnSSL_SetVerifyProperties_gnutls PARAMS((void));
  82 #endif
  83
  84 #define SHA256_STRING_LEN       (32 * 2 + 1)
  85
  86 static bool ConnSSL_Init_SSL PARAMS(( CONNECTION *c ));
  87 static int ConnectAccept PARAMS(( CONNECTION *c, bool connect ));
  88 static int ConnSSL_HandleError PARAMS(( CONNECTION *c, const int code, const char *fname ));
  89
  90 #ifdef HAVE_LIBGNUTLS
  91 static char * openreadclose(const char *name, size_t *len)
  92 {
  93         char *buf = NULL;
  94         struct stat s;
  95         ssize_t br;
  96         int fd = open(name, O_RDONLY);
  97         if (fd < 0) {
  98                 Log(LOG_ERR, "Could not open %s: %s", name, strerror(errno));
  99                 return NULL;
 100         }
 101         if (fstat(fd, &s)) {
 102                 Log(LOG_ERR, "Could not fstat %s: %s", name, strerror(errno));
 103                 goto out;
 104         }
 105         if (!S_ISREG(s.st_mode)) {
 106                 Log(LOG_ERR, "%s: Not a regular file", name);
 107                 goto out;
 108         }
 109         if (s.st_size <= 0) {
 110                 Log(LOG_ERR, "%s: invalid file length (size %ld <= 0)", name, (long) s.st_size);
 111                 goto out;
 112         }
 113         buf = malloc(s.st_size);
 114         if (!buf) {
 115                 Log(LOG_ERR, "Could not malloc %lu bytes for file %s: %s", s.st_size, name, strerror(errno));
 116                 goto out;
 117         }
 118         br = read(fd, buf, s.st_size);
 119         if (br != (ssize_t)s.st_size) {
 120                 Log(LOG_ERR, "Could not read file %s: read returned %ld, expected %ld: %s",
 121                         name, (long) br, (long) s.st_size, br == -1 ? strerror(errno):"short read?!");
 122                 memset(buf, 0, s.st_size);
 123                 free(buf);
 124                 buf = NULL;
 125         } else {
 126                 *len = br;
 127         }
 128 out:
 129         close(fd);
 130         return buf;
 131 }
 132 #endif
 133
 134
 135 #ifdef HAVE_LIBSSL
 136 /**
 137  * Log OpenSSL error message.
 138  *
 139  * @param level The log level
 140  * @param msg The error message.
 141  * @param info Additional information text or NULL.
 142  */
 143 static void
 144 LogOpenSSL_CertInfo(int level, X509 * cert, const char *msg)
 145 {
 146         BIO *mem;
 147         char *memptr;
 148         long len;
 149
 150         assert(cert);
 151         assert(msg);
 152
 153         if (!cert)
 154                 return;
 155         mem = BIO_new(BIO_s_mem());
 156         if (!mem)
 157                 return;
 158         X509_NAME_print_ex(mem, X509_get_subject_name(cert), 0,
 159                            XN_FLAG_ONELINE);
 160         X509_NAME_print_ex(mem, X509_get_issuer_name(cert), 2, XN_FLAG_ONELINE);
 161         if (BIO_write(mem, "", 1) == 1) {
 162                 len = BIO_get_mem_data(mem, &memptr);
 163                 if (memptr && len > 0)
 164                         Log(level, "%s: \"%s\".", msg, memptr);
 165         }
 166         (void)BIO_set_close(mem, BIO_CLOSE);
 167         BIO_free(mem);
 168 }
 169
 170 static void
 171 LogOpenSSLError(const char *error, const char *info)
 172 {
 173         unsigned long err = ERR_get_error();
 174         char * errmsg = err
 175                 ? ERR_error_string(err, NULL)
 176                 : "Unable to determine error";
 177
 178         assert(error != NULL);
 179
 180         if (info)
 181                 Log(LOG_ERR, "%s: %s (%s)", error, info, errmsg);
 182         else
 183                 Log(LOG_ERR, "%s: %s", error, errmsg);
 184 }
 185
 186
 187 static int
 188 pem_passwd_cb(char *buf, int size, int rwflag, void *password)
 189 {
 190         array *pass = password;
 191         int passlen;
 192
 193         (void)rwflag;           /* rwflag is unused if DEBUG is not set. */
 194         assert(rwflag == 0);    /* 0 -> callback used for decryption.
 195                                  * See SSL_CTX_set_default_passwd_cb(3) */
 196
 197         passlen = (int) array_bytes(pass);
 198
 199         LogDebug("pem_passwd_cb buf size %d, array size %d", size, passlen);
 200         assert(passlen >= 0);
 201         if (passlen <= 0) {
 202                 Log(LOG_ERR, "PEM password required but not set [in pem_passwd_cb()]!");
 203                 return 0;
 204         }
 205         size = passlen > size ? size : passlen;
 206         memcpy(buf, (char *)(array_start(pass)), size);
 207         return size;
 208 }
 209
 210
 211 static int
 212 Verify_openssl(int preverify_ok, X509_STORE_CTX * ctx)
 213 {
 214 #ifdef DEBUG
 215         if (!preverify_ok) {
 216                 int err = X509_STORE_CTX_get_error(ctx);
 217                 LogDebug("Certificate validation failed: %s",
 218                          X509_verify_cert_error_string(err));
 219         }
 220 #else
 221         (void)preverify_ok;
 222         (void)ctx;
 223 #endif
 224
 225         /* Always(!) return success as we have to deal with invalid
 226          * (self-signed, expired, ...) client certificates and with invalid
 227          * server certificates when "SSLVerify" is disabled, which we don't
 228          * know at this stage. Therefore we postpone this check, it will be
 229          * (and has to be!) handled in cb_connserver_login_ssl(). */
 230         return 1;
 231 }
 232 #endif
 233
 234
 235 static bool
 236 Load_DH_params(void)
 237 {
 238 #ifdef HAVE_LIBSSL
 239         FILE *fp;
 240         bool ret = true;
 241
 242         if (!Conf_SSLOptions.DHFile) {
 243                 Log(LOG_NOTICE, "Configuration option \"DHFile\" not set!");
 244                 return false;
 245         }
 246         fp = fopen(Conf_SSLOptions.DHFile, "r");
 247         if (!fp) {
 248                 Log(LOG_ERR, "%s: %s", Conf_SSLOptions.DHFile, strerror(errno));
 249                 return false;
 250         }
 251         dh_params = PEM_read_DHparams(fp, NULL, NULL, NULL);
 252         if (!dh_params) {
 253                 Log(LOG_ERR, "%s: Failed to read SSL DH parameters!",
 254                     Conf_SSLOptions.DHFile);
 255                 ret = false;
 256         }
 257         fclose(fp);
 258         return ret;
 259 #endif
 260 #ifdef HAVE_LIBGNUTLS
 261         bool need_dhgenerate = true;
 262         int err;
 263         gnutls_dh_params_t tmp_dh_params;
 264
 265         err = gnutls_dh_params_init(&tmp_dh_params);
 266         if (err < 0) {
 267                 Log(LOG_ERR, "Failed to initialize SSL DH parameters: %s",
 268                     gnutls_strerror(err));
 269                 return false;
 270         }
 271         if (Conf_SSLOptions.DHFile) {
 272                 gnutls_datum_t dhparms;
 273                 size_t size;
 274                 dhparms.data = (unsigned char *) openreadclose(Conf_SSLOptions.DHFile, &size);
 275                 if (dhparms.data) {
 276                         dhparms.size = size;
 277                         err = gnutls_dh_params_import_pkcs3(tmp_dh_params, &dhparms, GNUTLS_X509_FMT_PEM);
 278                         if (err == 0)
 279                                 need_dhgenerate = false;
 280                         else
 281                                 Log(LOG_ERR,
 282                                     "Failed to initialize SSL DH parameters: %s",
 283                                     gnutls_strerror(err));
 284
 285                         memset(dhparms.data, 0, size);
 286                         free(dhparms.data);
 287                 }
 288         }
 289         if (need_dhgenerate) {
 290                 Log(LOG_WARNING,
 291                     "DHFile not set, generating %u bit DH parameters. This may take a while ...",
 292                     DH_BITS);
 293                 err = gnutls_dh_params_generate2(tmp_dh_params, DH_BITS);
 294                 if (err < 0) {
 295                         Log(LOG_ERR, "Failed to generate SSL DH parameters: %s",
 296                             gnutls_strerror(err));
 297                         return false;
 298                 }
 299         }
 300         dh_params = tmp_dh_params;
 301         return true;
 302 #endif
 303 }
 304
 305
 306 void ConnSSL_Free(CONNECTION *c)
 307 {
 308 #ifdef HAVE_LIBSSL
 309         SSL *ssl = c->ssl_state.ssl;
 310         if (ssl) {
 311                 SSL_shutdown(ssl);
 312                 SSL_free(ssl);
 313                 c->ssl_state.ssl = NULL;
 314                 if (c->ssl_state.fingerprint) {
 315                         free(c->ssl_state.fingerprint);
 316                         c->ssl_state.fingerprint = NULL;
 317                 }
 318         }
 319 #endif
 320 #ifdef HAVE_LIBGNUTLS
 321         gnutls_session_t sess = c->ssl_state.gnutls_session;
 322         if (Conn_OPTION_ISSET(c, CONN_SSL)) {
 323                 gnutls_bye(sess, GNUTLS_SHUT_RDWR);
 324                 gnutls_deinit(sess);
 325         }
 326         x509_cred_slot *slot = array_get(&x509_creds, sizeof(x509_cred_slot), c->ssl_state.x509_cred_idx);
 327         assert(slot != NULL);
 328         assert(slot->refcnt > 0);
 329         assert(slot->x509_cred != NULL);
 330         slot->refcnt--;
 331         if ((c->ssl_state.x509_cred_idx != x509_cred_idx) && (slot->refcnt <= 0)) {
 332                 LogDebug("Discarding X509 certificate credentials from slot %zd.",
 333                          c->ssl_state.x509_cred_idx);
 334                 gnutls_certificate_free_keys(slot->x509_cred);
 335                 gnutls_certificate_free_credentials(slot->x509_cred);
 336                 slot->x509_cred = NULL;
 337                 gnutls_dh_params_deinit(slot->dh_params);
 338                 slot->dh_params = NULL;
 339                 slot->refcnt = 0;
 340         }
 341 #endif
 342         assert(Conn_OPTION_ISSET(c, CONN_SSL));
 343         /* can't just set bitmask to 0 -- there are other, non-ssl related flags, e.g. CONN_ZIP. */
 344         Conn_OPTION_DEL(c, CONN_SSL_FLAGS_ALL);
 345 }
 346
 347
 348 bool
 349 ConnSSL_InitLibrary( void )
 350 {
 351         if (!Conf_SSLInUse()) {
 352                 LogDebug("SSL not in use, skipping initialization.");
 353                 return true;
 354         }
 355
 356 #ifdef HAVE_LIBSSL
 357         SSL_CTX *newctx;
 358
 359 #if OPENSSL_API_COMPAT < 0x10100000L
 360         if (!ssl_ctx) {
 361                 SSL_library_init();
 362                 SSL_load_error_strings();
 363         }
 364 #endif
 365
 366         if (!RAND_status()) {
 367                 Log(LOG_ERR, "OpenSSL PRNG not seeded: /dev/urandom missing?");
 368                 /*
 369                  * it is probably best to fail and let the user install EGD or
 370                  * a similar program if no kernel random device is available.
 371                  * According to OpenSSL RAND_egd(3): "The automatic query of
 372                  * /var/run/egd-pool et al was added in OpenSSL 0.9.7";
 373                  * so it makes little sense to deal with PRNGD seeding ourselves.
 374                  */
 375                 array_free(&Conf_SSLOptions.ListenPorts);
 376                 return false;
 377         }
 378
 379         newctx = SSL_CTX_new(SSLv23_method());
 380         if (!newctx) {
 381                 LogOpenSSLError("Failed to create SSL context", NULL);
 382                 array_free(&Conf_SSLOptions.ListenPorts);
 383                 return false;
 384         }
 385
 386         if (!ConnSSL_LoadServerKey_openssl(newctx)) {
 387                 /* Failed to read new key but an old ssl context
 388                  * already exists -> reuse old context */
 389                 if (ssl_ctx) {
 390                         SSL_CTX_free(newctx);
 391                         Log(LOG_WARNING,
 392                         "Re-Initializing of SSL failed, using old keys!");
 393                         return true;
 394                 }
 395                 /* No preexisting old context -> error. */
 396                 goto out;
 397         }
 398
 399         if (SSL_CTX_set_cipher_list(newctx, Conf_SSLOptions.CipherList) == 0) {
 400                 Log(LOG_ERR, "Failed to apply OpenSSL cipher list \"%s\"!",
 401                     Conf_SSLOptions.CipherList);
 402                 goto out;
 403         }
 404
 405         SSL_CTX_set_session_id_context(newctx, (unsigned char *)"ngircd", 6);
 406         if (!ConnSSL_SetVerifyProperties_openssl(newctx))
 407                 goto out;
 408         SSL_CTX_set_options(newctx,
 409                             SSL_OP_SINGLE_DH_USE | SSL_OP_NO_SSLv2 |
 410                             SSL_OP_NO_SSLv3 | SSL_OP_NO_TLSv1 | SSL_OP_NO_TLSv1_1 |
 411                             SSL_OP_NO_COMPRESSION);
 412         SSL_CTX_set_mode(newctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
 413         SSL_CTX_free(ssl_ctx);
 414         ssl_ctx = newctx;
 415         Log(LOG_INFO, "%s initialized.", OpenSSL_version(OPENSSL_VERSION));
 416         return true;
 417 out:
 418         SSL_CTX_free(newctx);
 419         array_free(&Conf_SSLOptions.ListenPorts);
 420         return false;
 421 #endif
 422 #ifdef HAVE_LIBGNUTLS
 423         int err;
 424         static bool initialized;
 425
 426         if (!initialized) {
 427                 err = gnutls_global_init();
 428                 if (err) {
 429                         Log(LOG_ERR, "Failed to initialize GnuTLS: %s",
 430                             gnutls_strerror(err));
 431                         goto out;
 432                 }
 433         }
 434
 435         if (!ConnSSL_LoadServerKey_gnutls())
 436                 goto out;
 437
 438         if (priorities_cache != NULL) {
 439                 gnutls_priority_deinit(priorities_cache);
 440         }
 441         if (gnutls_priority_init(&priorities_cache, Conf_SSLOptions.CipherList,
 442                                  NULL) != GNUTLS_E_SUCCESS) {
 443                 Log(LOG_ERR,
 444                     "Failed to apply GnuTLS cipher list \"%s\"!",
 445                     Conf_SSLOptions.CipherList);
 446                 goto out;
 447         }
 448
 449         if (!ConnSSL_SetVerifyProperties_gnutls())
 450                 goto out;
 451
 452         Log(LOG_INFO, "GnuTLS %s initialized.", gnutls_check_version(NULL));
 453         initialized = true;
 454         return true;
 455 out:
 456         array_free(&Conf_SSLOptions.ListenPorts);
 457         return false;
 458 #endif
 459 }
 460
 461
 462 #ifdef HAVE_LIBGNUTLS
 463 static bool
 464 ConnSSL_SetVerifyProperties_gnutls(void)
 465 {
 466         int err;
 467
 468         if (!Conf_SSLOptions.CAFile)
 469                 return true;
 470
 471         x509_cred_slot *slot = array_get(&x509_creds, sizeof(x509_cred_slot), x509_cred_idx);
 472         gnutls_certificate_credentials_t x509_cred = slot->x509_cred;
 473
 474         err = gnutls_certificate_set_x509_trust_file(x509_cred,
 475                                                      Conf_SSLOptions.CAFile,
 476                                                      GNUTLS_X509_FMT_PEM);
 477         if (err < 0) {
 478                 Log(LOG_ERR, "Failed to load x509 trust file %s: %s",
 479                     Conf_SSLOptions.CAFile, gnutls_strerror(err));
 480                 return false;
 481         }
 482         if (Conf_SSLOptions.CRLFile) {
 483                 err =
 484                     gnutls_certificate_set_x509_crl_file(x509_cred,
 485                                                          Conf_SSLOptions.CRLFile,
 486                                                          GNUTLS_X509_FMT_PEM);
 487                 if (err < 0) {
 488                         Log(LOG_ERR, "Failed to load x509 crl file %s: %s",
 489                             Conf_SSLOptions.CRLFile, gnutls_strerror(err));
 490                         return false;
 491                 }
 492         }
 493         return true;
 494 }
 495
 496
 497 static bool
 498 ConnSSL_LoadServerKey_gnutls(void)
 499 {
 500         int err;
 501         const char *cert_file;
 502
 503         x509_cred_slot *slot = NULL;
 504         gnutls_certificate_credentials_t x509_cred;
 505
 506         err = gnutls_certificate_allocate_credentials(&x509_cred);
 507         if (err < 0) {
 508                 Log(LOG_ERR, "Failed to allocate certificate credentials: %s",
 509                     gnutls_strerror(err));
 510                 return false;
 511         }
 512
 513         if (array_bytes(&Conf_SSLOptions.KeyFilePassword))
 514                 Log(LOG_WARNING,
 515                     "Ignoring SSL \"KeyFilePassword\": Not supported by GnuTLS.");
 516
 517         if (!Load_DH_params())
 518                 return false;
 519
 520         gnutls_certificate_set_dh_params(x509_cred, dh_params);
 521
 522         cert_file = Conf_SSLOptions.CertFile ?
 523                         Conf_SSLOptions.CertFile : Conf_SSLOptions.KeyFile;
 524         if (Conf_SSLOptions.KeyFile) {
 525                 err = gnutls_certificate_set_x509_key_file(x509_cred, cert_file,
 526                                                            Conf_SSLOptions.KeyFile,
 527                                                            GNUTLS_X509_FMT_PEM);
 528                 if (err < 0) {
 529                         Log(LOG_ERR,
 530                             "Failed to set certificate key file (cert %s, key %s): %s",
 531                             cert_file,
 532                             Conf_SSLOptions.KeyFile ? Conf_SSLOptions.KeyFile : "(NULL)",
 533                             gnutls_strerror(err));
 534                         return false;
 535                 }
 536         }
 537
 538         /* Free currently active x509 context (if any) unless it is still in use */
 539         slot = array_get(&x509_creds, sizeof(x509_cred_slot), x509_cred_idx);
 540         if ((slot != NULL) && (slot->refcnt <= 0) && (slot->x509_cred != NULL)) {
 541                 LogDebug("Discarding X509 certificate credentials from slot %zd.",
 542                          x509_cred_idx);
 543                 gnutls_certificate_free_keys(slot->x509_cred);
 544                 gnutls_certificate_free_credentials(slot->x509_cred);
 545                 slot->x509_cred = NULL;
 546                 gnutls_dh_params_deinit(slot->dh_params);
 547                 slot->dh_params = NULL;
 548                 slot->refcnt = 0;
 549         }
 550
 551         /* Find free slot */
 552         x509_cred_idx = (size_t) -1;
 553         size_t i;
 554         for (slot = array_start(&x509_creds), i = 0;
 555              i < array_length(&x509_creds, sizeof(x509_cred_slot));
 556              slot++, i++) {
 557                 if (slot->refcnt <= 0) {
 558                         x509_cred_idx = i;
 559                         break;
 560                 }
 561         }
 562         /* ... allocate new slot otherwise. */
 563         if (x509_cred_idx == (size_t) -1) {
 564                 x509_cred_idx = array_length(&x509_creds, sizeof(x509_cred_slot));
 565                 slot = array_alloc(&x509_creds, sizeof(x509_cred_slot), x509_cred_idx);
 566                 if (slot == NULL) {
 567                         Log(LOG_ERR, "Failed to allocate new slot for certificate credentials");
 568                         return false;
 569                 }
 570         }
 571         Log(LOG_INFO, "Storing new X509 certificate credentials in slot %zd.", x509_cred_idx);
 572         slot->x509_cred = x509_cred;
 573         slot->refcnt = 0;
 574
 575         return true;
 576 }
 577 #endif
 578
 579
 580 #ifdef HAVE_LIBSSL
 581 static bool
 582 ConnSSL_LoadServerKey_openssl(SSL_CTX *ctx)
 583 {
 584         char *cert_key;
 585
 586         assert(ctx);
 587         SSL_CTX_set_default_passwd_cb(ctx, pem_passwd_cb);
 588         SSL_CTX_set_default_passwd_cb_userdata(ctx, &Conf_SSLOptions.KeyFilePassword);
 589
 590         if (!Conf_SSLOptions.KeyFile)
 591                 return true;
 592
 593         if (SSL_CTX_use_PrivateKey_file(ctx, Conf_SSLOptions.KeyFile, SSL_FILETYPE_PEM) != 1) {
 594                 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
 595                 LogOpenSSLError("Failed to add private key", Conf_SSLOptions.KeyFile);
 596                 return false;
 597         }
 598
 599         cert_key = Conf_SSLOptions.CertFile ? Conf_SSLOptions.CertFile:Conf_SSLOptions.KeyFile;
 600         if (SSL_CTX_use_certificate_chain_file(ctx, cert_key) != 1) {
 601                 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
 602                 LogOpenSSLError("Failed to load certificate chain", cert_key);
 603                 return false;
 604         }
 605
 606         array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
 607
 608         if (!SSL_CTX_check_private_key(ctx)) {
 609                 LogOpenSSLError("Server private key does not match certificate", NULL);
 610                 return false;
 611         }
 612         if (Load_DH_params()) {
 613                 if (SSL_CTX_set_tmp_dh(ctx, dh_params) != 1)
 614                         LogOpenSSLError("Error setting DH parameters", Conf_SSLOptions.DHFile);
 615                 /* don't return false here: the non-DH modes will still work */
 616                 DH_free(dh_params);
 617                 dh_params = NULL;
 618         }
 619         return true;
 620 }
 621
 622
 623 static bool
 624 ConnSSL_SetVerifyProperties_openssl(SSL_CTX * ctx)
 625 {
 626         X509_STORE *store = NULL;
 627         X509_LOOKUP *lookup;
 628         bool ret = false;
 629
 630         if (!Conf_SSLOptions.CAFile)
 631                 return true;
 632
 633         if (SSL_CTX_load_verify_locations(ctx, Conf_SSLOptions.CAFile, NULL) !=
 634             1) {
 635                 LogOpenSSLError("SSL_CTX_load_verify_locations", NULL);
 636                 goto out;
 637         }
 638
 639         if (Conf_SSLOptions.CRLFile) {
 640                 X509_VERIFY_PARAM *param = X509_VERIFY_PARAM_new();
 641                 X509_VERIFY_PARAM_set_flags(param, X509_V_FLAG_CRL_CHECK);
 642                 SSL_CTX_set1_param(ctx, param);
 643
 644                 store = SSL_CTX_get_cert_store(ctx);
 645                 assert(store);
 646                 lookup = X509_STORE_add_lookup(store, X509_LOOKUP_file());
 647                 if (!lookup) {
 648                         LogOpenSSLError("X509_STORE_add_lookup",
 649                                         Conf_SSLOptions.CRLFile);
 650                         goto out;
 651                 }
 652
 653                 if (X509_load_crl_file
 654                     (lookup, Conf_SSLOptions.CRLFile, X509_FILETYPE_PEM) != 1) {
 655                         LogOpenSSLError("X509_load_crl_file",
 656                                         Conf_SSLOptions.CRLFile);
 657                         goto out;
 658                 }
 659         }
 660
 661         SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER|SSL_VERIFY_CLIENT_ONCE,
 662                            Verify_openssl);
 663         SSL_CTX_set_verify_depth(ctx, MAX_CERT_CHAIN_LENGTH);
 664         ret = true;
 665 out:
 666         if (Conf_SSLOptions.CRLFile)
 667                 free(Conf_SSLOptions.CRLFile);
 668         Conf_SSLOptions.CRLFile = NULL;
 669         return ret;
 670 }
 671
 672
 673 #endif
 674 static bool
 675 ConnSSL_Init_SSL(CONNECTION *c)
 676 {
 677         int ret;
 678
 679         LogDebug("Initializing SSL ...");
 680         assert(c != NULL);
 681
 682 #ifdef HAVE_LIBSSL
 683         if (!ssl_ctx) {
 684                 Log(LOG_ERR,
 685                     "Can't initialize SSL context, OpenSSL initialization failed at startup!");
 686                 return false;
 687         }
 688         assert(c->ssl_state.ssl == NULL);
 689         assert(c->ssl_state.fingerprint == NULL);
 690
 691         c->ssl_state.ssl = SSL_new(ssl_ctx);
 692         if (!c->ssl_state.ssl) {
 693                 LogOpenSSLError("Failed to create SSL structure", NULL);
 694                 return false;
 695         }
 696         Conn_OPTION_ADD(c, CONN_SSL);
 697
 698         ret = SSL_set_fd(c->ssl_state.ssl, c->sock);
 699         if (ret != 1) {
 700                 LogOpenSSLError("Failed to set SSL file descriptor", NULL);
 701                 ConnSSL_Free(c);
 702                 return false;
 703         }
 704 #endif
 705 #ifdef HAVE_LIBGNUTLS
 706         Conn_OPTION_ADD(c, CONN_SSL);
 707         ret = gnutls_priority_set(c->ssl_state.gnutls_session, priorities_cache);
 708         if (ret != GNUTLS_E_SUCCESS) {
 709                 Log(LOG_ERR, "Failed to set GnuTLS session priorities: %s",
 710                     gnutls_strerror(ret));
 711                 ConnSSL_Free(c);
 712                 return false;
 713         }
 714         /*
 715          * The intermediate (long) cast is here to avoid a warning like:
 716          * "cast to pointer from integer of different size" on 64-bit platforms.
 717          * There doesn't seem to be an alternate GNUTLS API we could use instead, see e.g.
 718          * http://www.mail-archive.com/help-gnutls@gnu.org/msg00286.html
 719          */
 720         gnutls_transport_set_ptr(c->ssl_state.gnutls_session,
 721                                  (gnutls_transport_ptr_t) (long) c->sock);
 722         gnutls_certificate_server_set_request(c->ssl_state.gnutls_session,
 723                                               GNUTLS_CERT_REQUEST);
 724
 725         LogDebug("Using X509 credentials from slot %zd.", x509_cred_idx);
 726         c->ssl_state.x509_cred_idx = x509_cred_idx;
 727         x509_cred_slot *slot = array_get(&x509_creds, sizeof(x509_cred_slot), x509_cred_idx);
 728         slot->refcnt++;
 729         ret = gnutls_credentials_set(c->ssl_state.gnutls_session,
 730                                      GNUTLS_CRD_CERTIFICATE, slot->x509_cred);
 731         if (ret != 0) {
 732                 Log(LOG_ERR, "Failed to set SSL credentials: %s",
 733                     gnutls_strerror(ret));
 734                 ConnSSL_Free(c);
 735                 return false;
 736         }
 737         gnutls_dh_set_prime_bits(c->ssl_state.gnutls_session, DH_BITS_MIN);
 738 #endif
 739         return true;
 740 }
 741
 742
 743 bool
 744 ConnSSL_PrepareConnect(CONNECTION * c, CONF_SERVER * s)
 745 {
 746         bool ret;
 747 #ifdef HAVE_LIBGNUTLS
 748         int err;
 749
 750         err = gnutls_init(&c->ssl_state.gnutls_session, GNUTLS_CLIENT);
 751         if (err) {
 752                 Log(LOG_ERR, "Failed to initialize new SSL session: %s",
 753                     gnutls_strerror(err));
 754                 return false;
 755         }
 756 #endif
 757         ret = ConnSSL_Init_SSL(c);
 758         if (!ret)
 759                 return false;
 760         Conn_OPTION_ADD(c, CONN_SSL_CONNECT);
 761
 762 #ifdef HAVE_LIBSSL
 763         assert(c->ssl_state.ssl);
 764
 765         X509_VERIFY_PARAM *param = SSL_get0_param(c->ssl_state.ssl);
 766         X509_VERIFY_PARAM_set_hostflags(param, X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS);
 767         int err = X509_VERIFY_PARAM_set1_host(param, s->host, 0);
 768         if (err != 1) {
 769                 Log(LOG_ERR,
 770                     "Cannot set up hostname verification for '%s': %u",
 771                     s->host, err);
 772                 return false;
 773         }
 774
 775         if (s->SSLVerify)
 776                 SSL_set_verify(c->ssl_state.ssl, SSL_VERIFY_PEER,
 777                                Verify_openssl);
 778         else
 779                 SSL_set_verify(c->ssl_state.ssl, SSL_VERIFY_NONE, NULL);
 780 #endif
 781
 782         return true;
 783 }
 784
 785
 786 /**
 787  * Check and handle error return codes after failed calls to SSL functions.
 788  *
 789  * OpenSSL:
 790  * SSL_connect(), SSL_accept(), SSL_do_handshake(), SSL_read(), SSL_peek(), or
 791  * SSL_write() on ssl.
 792  *
 793  * GnuTLS:
 794  * gnutlsssl_read(), gnutls_write() or gnutls_handshake().
 795  *
 796  * @param c The connection handle.
 797  * @prarm code The return code.
 798  * @param fname The name of the function in which the error occurred.
 799  * @return -1 on fatal errors, 0 if we can try again later.
 800  */
 801 static int
 802 ConnSSL_HandleError(CONNECTION * c, const int code, const char *fname)
 803 {
 804 #ifdef HAVE_LIBSSL
 805         int ret = SSL_ERROR_SYSCALL;
 806         unsigned long sslerr;
 807         int real_errno = errno;
 808
 809         ret = SSL_get_error(c->ssl_state.ssl, code);
 810
 811         switch (ret) {
 812         case SSL_ERROR_WANT_READ:
 813                 io_event_del(c->sock, IO_WANTWRITE);
 814                 Conn_OPTION_ADD(c, CONN_SSL_WANT_READ);
 815                 return 0;       /* try again later */
 816         case SSL_ERROR_WANT_WRITE:
 817                 io_event_del(c->sock, IO_WANTREAD);
 818                 Conn_OPTION_ADD(c, CONN_SSL_WANT_WRITE); /* fall through */
 819         case SSL_ERROR_NONE:
 820                 return 0;       /* try again later */
 821         case SSL_ERROR_ZERO_RETURN:
 822                 LogDebug("SSL connection shut down normally.");
 823                 break;
 824         case SSL_ERROR_SYSCALL:
 825                 /* SSL_ERROR_WANT_CONNECT, SSL_ERROR_WANT_ACCEPT,
 826                  * and SSL_ERROR_WANT_X509_LOOKUP */
 827                 sslerr = ERR_get_error();
 828                 if (sslerr) {
 829                         Log(LOG_ERR, "SSL error: %s [in %s()]!",
 830                             ERR_error_string(sslerr, NULL), fname);
 831                 } else {
 832                         switch (code) { /* EOF that violated protocol */
 833                         case 0:
 834                                 Log(LOG_ERR,
 835                                     "SSL error, client disconnected [in %s()]!",
 836                                     fname);
 837                                 break;
 838                         case -1:
 839                                 /* Low level socket I/O error, check errno. But
 840                                  * we don't need to log this here, the generic
 841                                  * connection layer will take care of it. */
 842                                 LogDebug("SSL error: %s [in %s()]!",
 843                                          strerror(real_errno), fname);
 844                         }
 845                 }
 846                 break;
 847         case SSL_ERROR_SSL:
 848                 LogOpenSSLError("SSL protocol error", fname);
 849                 break;
 850         default:
 851                 Log(LOG_ERR, "Unknown SSL error %d [in %s()]!", ret, fname);
 852         }
 853         ConnSSL_Free(c);
 854         return -1;
 855 #endif
 856 #ifdef HAVE_LIBGNUTLS
 857         switch (code) {
 858         case GNUTLS_E_AGAIN:
 859         case GNUTLS_E_INTERRUPTED:
 860                 if (gnutls_record_get_direction(c->ssl_state.gnutls_session)) {
 861                         Conn_OPTION_ADD(c, CONN_SSL_WANT_WRITE);
 862                         io_event_del(c->sock, IO_WANTREAD);
 863                 } else {
 864                         Conn_OPTION_ADD(c, CONN_SSL_WANT_READ);
 865                         io_event_del(c->sock, IO_WANTWRITE);
 866                 }
 867                 break;
 868         default:
 869                 assert(code < 0);
 870                 if (gnutls_error_is_fatal(code)) {
 871                         Log(LOG_ERR, "SSL error: %s [%s].",
 872                             gnutls_strerror(code), fname);
 873                         ConnSSL_Free(c);
 874                         return -1;
 875                 }
 876         }
 877         return 0;
 878 #endif
 879 }
 880
 881
 882 #ifdef HAVE_LIBGNUTLS
 883 static void *
 884 LogMalloc(size_t s)
 885 {
 886         void *mem = malloc(s);
 887         if (!mem)
 888                 Log(LOG_ERR, "Out of memory: Could not allocate %lu byte",
 889                     (unsigned long)s);
 890         return mem;
 891 }
 892
 893
 894 static void
 895 LogGnuTLS_CertInfo(int level, gnutls_x509_crt_t cert, const char *msg)
 896 {
 897         char *dn, *issuer_dn;
 898         size_t size = 0;
 899         int err = gnutls_x509_crt_get_dn(cert, NULL, &size);
 900         if (size == 0) {
 901                 Log(LOG_ERR, "gnutls_x509_crt_get_dn: size == 0");
 902                 return;
 903         }
 904         if (err && err != GNUTLS_E_SHORT_MEMORY_BUFFER)
 905                 goto err_crt_get;
 906         dn = LogMalloc(size);
 907         if (!dn)
 908                 return;
 909         err = gnutls_x509_crt_get_dn(cert, dn, &size);
 910         if (err)
 911                 goto err_crt_get;
 912         gnutls_x509_crt_get_issuer_dn(cert, NULL, &size);
 913         assert(size);
 914         issuer_dn = LogMalloc(size);
 915         if (!issuer_dn) {
 916                 Log(level, "%s: Distinguished Name: %s", msg, dn);
 917                 free(dn);
 918                 return;
 919         }
 920         gnutls_x509_crt_get_issuer_dn(cert, issuer_dn, &size);
 921         Log(level, "%s: Distinguished Name: \"%s\", Issuer \"%s\"", msg, dn,
 922             issuer_dn);
 923         free(dn);
 924         free(issuer_dn);
 925         return;
 926
 927       err_crt_get:
 928         Log(LOG_ERR, "gnutls_x509_crt_get_dn: %s", gnutls_strerror(err));
 929         return;
 930 }
 931 #endif
 932
 933
 934 static void
 935 ConnSSL_LogCertInfo( CONNECTION * c, bool connect)
 936 {
 937         bool cert_seen = false, cert_ok = false;
 938         char msg[128];
 939 #ifdef HAVE_LIBSSL
 940         const char *comp_alg = "no compression";
 941         const void *comp;
 942         X509 *peer_cert = NULL;
 943         SSL *ssl = c->ssl_state.ssl;
 944
 945         assert(ssl);
 946
 947         comp = SSL_get_current_compression(ssl);
 948         if (comp)
 949                 comp_alg = SSL_COMP_get_name(comp);
 950         Log(LOG_INFO, "Connection %d: initialized %s using cipher %s, %s.",
 951             c->sock, SSL_get_version(ssl), SSL_get_cipher(ssl), comp_alg);
 952         peer_cert = SSL_get_peer_certificate(ssl);
 953         if (peer_cert) {
 954                 cert_seen = true;
 955
 956                 if (connect) {
 957                         /* Outgoing connection. Verify the remote server! */
 958                         int err = SSL_get_verify_result(ssl);
 959                         if (err == X509_V_OK) {
 960                                 const char *peername = SSL_get0_peername(ssl);
 961                                 if (peername != NULL)
 962                                         cert_ok = true;
 963                                 LogDebug("X509_V_OK, peername = '%s'", peername);
 964                         } else
 965                                 Log(LOG_WARNING, "Certificate validation failed: %s!",
 966                                     X509_verify_cert_error_string(err));
 967
 968                         snprintf(msg, sizeof(msg), "Got %svalid server certificate",
 969                                  cert_ok ? "" : "in");
 970                         LogOpenSSL_CertInfo(LOG_INFO, peer_cert, msg);
 971                 } else {
 972                         /* Incoming connection.
 973                          * Accept all certificates, don't depend on their
 974                          * validity: for example, we don't know the hostname
 975                          * to check, because we not yet even know if this is a
 976                          * server connection at all and if so, which one, so we
 977                          * don't know a host name to look for. On the other
 978                          * hand we want client certificates, for example for
 979                          * "CertFP" authentication with services ... */
 980                         LogOpenSSL_CertInfo(LOG_INFO, peer_cert,
 981                                             "Got unchecked client certificate");
 982                 }
 983
 984                 X509_free(peer_cert);
 985         }
 986 #endif
 987 #ifdef HAVE_LIBGNUTLS
 988         unsigned int status;
 989         gnutls_credentials_type_t cred;
 990         gnutls_session_t sess = c->ssl_state.gnutls_session;
 991         gnutls_cipher_algorithm_t cipher = gnutls_cipher_get(sess);
 992
 993         Log(LOG_INFO, "Connection %d: initialized %s using cipher %s-%s.",
 994             c->sock,
 995             gnutls_protocol_get_name(gnutls_protocol_get_version(sess)),
 996             gnutls_cipher_get_name(cipher),
 997             gnutls_mac_get_name(gnutls_mac_get(sess)));
 998         cred = gnutls_auth_get_type(c->ssl_state.gnutls_session);
 999         if (cred == GNUTLS_CRD_CERTIFICATE && connect) {
1000                 cert_seen = true;
1001                 int verify =
1002                     gnutls_certificate_verify_peers2(c->
1003                                                      ssl_state.gnutls_session,
1004                                                      &status);
1005                 if (verify < 0) {
1006                         Log(LOG_ERR,
1007                             "gnutls_certificate_verify_peers2 failed: %s",
1008                             gnutls_strerror(verify));
1009                         goto done_cn_validation;
1010                 } else if (status) {
1011                         gnutls_datum_t out;
1012
1013                         if (gnutls_certificate_verification_status_print
1014                             (status, gnutls_certificate_type_get(sess), &out,
1015                              0) == GNUTLS_E_SUCCESS) {
1016                                 Log(LOG_ERR,
1017                                     "Certificate validation failed: %s",
1018                                     out.data);
1019                                 gnutls_free(out.data);
1020                         }
1021                 }
1022
1023                 gnutls_x509_crt_t cert;
1024                 unsigned cert_list_size;
1025                 const gnutls_datum_t *cert_list =
1026                     gnutls_certificate_get_peers(sess, &cert_list_size);
1027                 if (!cert_list || cert_list_size == 0) {
1028                         Log(LOG_ERR, "No certificates found");
1029                         goto done_cn_validation;
1030                 }
1031                 int err = gnutls_x509_crt_init(&cert);
1032                 if (err < 0) {
1033                         Log(LOG_ERR,
1034                             "Failed to initialize x509 certificate: %s",
1035                             gnutls_strerror(err));
1036                         goto done_cn_validation;
1037                 }
1038                 err = gnutls_x509_crt_import(cert, cert_list,
1039                                            GNUTLS_X509_FMT_DER);
1040                 if (err < 0) {
1041                         Log(LOG_ERR, "Failed to parse the certificate: %s",
1042                             gnutls_strerror(err));
1043                         goto done_cn_validation;
1044                 }
1045                 err = gnutls_x509_crt_check_hostname(cert, c->host);
1046                 if (err == 0)
1047                         Log(LOG_ERR,
1048                             "Failed to verify the hostname, expected \"%s\"",
1049                             c->host);
1050                 else
1051                         cert_ok = verify == 0 && status == 0;
1052
1053                 snprintf(msg, sizeof(msg), "%svalid peer certificate",
1054                         cert_ok ? "" : "in");
1055                 LogGnuTLS_CertInfo(cert_ok ? LOG_DEBUG : LOG_ERR, cert, msg);
1056
1057                 gnutls_x509_crt_deinit(cert);
1058 done_cn_validation:
1059                 ;
1060         }
1061 #endif
1062         /*
1063          * can be used later to check if connection was authenticated, e.g.
1064          * if inbound connection tries to register itself as server.
1065          * Could also restrict /OPER to authenticated connections, etc.
1066          */
1067         if (cert_ok)
1068                 Conn_OPTION_ADD(c, CONN_SSL_PEERCERT_OK);
1069         if (!cert_seen)
1070                 Log(LOG_INFO, "Peer did not present a certificate.");
1071 }
1072
1073
1074 /*
1075  Accept incoming SSL connection.
1076  Return Values:
1077          1: SSL Connection established
1078          0: try again
1079         -1: SSL Connection not established due to fatal error.
1080 */
1081 int
1082 ConnSSL_Accept( CONNECTION *c )
1083 {
1084         assert(c != NULL);
1085         if (!Conn_OPTION_ISSET(c, CONN_SSL)) {
1086 #ifdef HAVE_LIBGNUTLS
1087                 int err = gnutls_init(&c->ssl_state.gnutls_session, GNUTLS_SERVER);
1088                 if (err) {
1089                         Log(LOG_ERR, "Failed to initialize new SSL session: %s",
1090                             gnutls_strerror(err));
1091                         return false;
1092                 }
1093 #endif
1094                 if (!ConnSSL_Init_SSL(c))
1095                         return -1;
1096         }
1097         return ConnectAccept(c, false );
1098 }
1099
1100
1101 int
1102 ConnSSL_Connect( CONNECTION *c )
1103 {
1104         assert(c != NULL);
1105 #ifdef HAVE_LIBSSL
1106         assert(c->ssl_state.ssl);
1107 #endif
1108         assert(Conn_OPTION_ISSET(c, CONN_SSL));
1109         return ConnectAccept(c, true);
1110 }
1111
1112 static int
1113 ConnSSL_InitCertFp( CONNECTION *c )
1114 {
1115         const char hex[] = "0123456789abcdef";
1116         int i;
1117
1118 #ifdef HAVE_LIBSSL
1119         unsigned char digest[EVP_MAX_MD_SIZE];
1120         unsigned int digest_size;
1121         X509 *cert;
1122
1123         cert = SSL_get_peer_certificate(c->ssl_state.ssl);
1124         if (!cert)
1125                 return 0;
1126
1127         if (!X509_digest(cert, EVP_sha256(), digest, &digest_size)) {
1128                 X509_free(cert);
1129                 return 0;
1130         }
1131
1132         X509_free(cert);
1133 #endif /* HAVE_LIBSSL */
1134 #ifdef HAVE_LIBGNUTLS
1135         gnutls_x509_crt_t cert;
1136         unsigned int cert_list_size;
1137         const gnutls_datum_t *cert_list;
1138         unsigned char digest[MAX_HASH_SIZE];
1139         size_t digest_size;
1140
1141         if (gnutls_certificate_type_get(c->ssl_state.gnutls_session) !=
1142                                         GNUTLS_CRT_X509)
1143                 return 0;
1144
1145         if (gnutls_x509_crt_init(&cert) != GNUTLS_E_SUCCESS)
1146                 return 0;
1147
1148         cert_list_size = 0;
1149         cert_list = gnutls_certificate_get_peers(c->ssl_state.gnutls_session,
1150                                                  &cert_list_size);
1151         if (!cert_list) {
1152                 gnutls_x509_crt_deinit(cert);
1153                 return 0;
1154         }
1155
1156         if (gnutls_x509_crt_import(cert, &cert_list[0],
1157                                    GNUTLS_X509_FMT_DER) != GNUTLS_E_SUCCESS) {
1158                 gnutls_x509_crt_deinit(cert);
1159                 return 0;
1160         }
1161
1162         digest_size = sizeof(digest);
1163         if (gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_SHA256, digest,
1164                                             &digest_size)) {
1165                 gnutls_x509_crt_deinit(cert);
1166                 return 0;
1167         }
1168
1169         gnutls_x509_crt_deinit(cert);
1170 #endif /* HAVE_LIBGNUTLS */
1171
1172         assert(c->ssl_state.fingerprint == NULL);
1173
1174         c->ssl_state.fingerprint = malloc(SHA256_STRING_LEN);
1175         if (!c->ssl_state.fingerprint)
1176                 return 0;
1177
1178         for (i = 0; i < (int)digest_size; i++) {
1179                 c->ssl_state.fingerprint[i * 2] = hex[digest[i] / 16];
1180                 c->ssl_state.fingerprint[i * 2 + 1] = hex[digest[i] % 16];
1181         }
1182         c->ssl_state.fingerprint[i * 2] = '\0';
1183
1184         return 1;
1185 }
1186
1187 /* accept/connect wrapper. if connect is true, connect to peer, otherwise wait for incoming connection */
1188 static int
1189 ConnectAccept( CONNECTION *c, bool connect)
1190 {
1191         int ret;
1192 #ifdef HAVE_LIBSSL
1193         SSL *ssl = c->ssl_state.ssl;
1194         assert(ssl != NULL);
1195
1196         ret = connect ? SSL_connect(ssl) : SSL_accept(ssl);
1197         if (1 != ret)
1198                 return ConnSSL_HandleError(c, ret, connect ? "SSL_connect": "SSL_accept");
1199 #endif
1200 #ifdef HAVE_LIBGNUTLS
1201         (void) connect;
1202         ret = gnutls_handshake(c->ssl_state.gnutls_session);
1203         if (ret)
1204                 return ConnSSL_HandleError(c, ret, "gnutls_handshake");
1205 #endif /* _GNUTLS */
1206         (void)ConnSSL_InitCertFp(c);
1207
1208         Conn_OPTION_DEL(c, (CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ|CONN_SSL_CONNECT));
1209         ConnSSL_LogCertInfo(c, connect);
1210
1211         Conn_StartLogin(CONNECTION2ID(c));
1212         return 1;
1213 }
1214
1215
1216 ssize_t
1217 ConnSSL_Write(CONNECTION *c, const void *buf, size_t count)
1218 {
1219         ssize_t bw;
1220
1221         Conn_OPTION_DEL(c, CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ);
1222
1223         assert(count > 0);
1224 #ifdef HAVE_LIBSSL
1225         bw = (ssize_t) SSL_write(c->ssl_state.ssl, buf, count);
1226 #endif
1227 #ifdef HAVE_LIBGNUTLS
1228         bw = gnutls_write(c->ssl_state.gnutls_session, buf, count);
1229 #endif
1230         if (bw > 0)
1231                 return bw;
1232         if (ConnSSL_HandleError( c, bw, "ConnSSL_Write") == 0)
1233                 errno = EAGAIN; /* try again */
1234         return -1;
1235 }
1236
1237
1238 ssize_t
1239 ConnSSL_Read(CONNECTION *c, void * buf, size_t count)
1240 {
1241         ssize_t br;
1242
1243         Conn_OPTION_DEL(c, CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ);
1244 #ifdef HAVE_LIBSSL
1245         br = (ssize_t) SSL_read(c->ssl_state.ssl, buf, count);
1246         if (br > 0)     /* on EOF we have to call ConnSSL_HandleError(), see SSL_read(3) */
1247                 return br;
1248 #endif
1249 #ifdef HAVE_LIBGNUTLS
1250         br = gnutls_read(c->ssl_state.gnutls_session, buf, count);
1251         if (br >= 0)    /* on EOF we must _not_ call ConnSSL_HandleError, see gnutls_record_recv(3) */
1252                 return br;
1253 #endif
1254         /* error on read: switch ConnSSL_HandleError() return values -> 0 is "try again", so return -1 and set EAGAIN */
1255         if (ConnSSL_HandleError(c, br, "ConnSSL_Read") == 0) {
1256                 errno = EAGAIN;
1257                 return -1;
1258         }
1259         return 0;
1260 }
1261
1262
1263 bool
1264 ConnSSL_GetCipherInfo(CONNECTION *c, char *buf, size_t len)
1265 {
1266 #ifdef HAVE_LIBSSL
1267         char *nl;
1268         SSL *ssl = c->ssl_state.ssl;
1269
1270         if (!ssl)
1271                 return false;
1272         *buf = 0;
1273         SSL_CIPHER_description(SSL_get_current_cipher(ssl), buf, len);
1274         nl = strchr(buf, '\n');
1275         if (nl)
1276                 *nl = 0;
1277         return true;
1278 #endif
1279 #ifdef HAVE_LIBGNUTLS
1280         if (Conn_OPTION_ISSET(c, CONN_SSL)) {
1281                 const char *name_cipher, *name_mac, *name_proto, *name_keyexchange;
1282                 unsigned keysize;
1283
1284                 gnutls_session_t sess = c->ssl_state.gnutls_session;
1285                 gnutls_cipher_algorithm_t cipher = gnutls_cipher_get(sess);
1286                 name_cipher = gnutls_cipher_get_name(cipher);
1287                 name_mac = gnutls_mac_get_name(gnutls_mac_get(sess));
1288                 keysize = gnutls_cipher_get_key_size(cipher) * 8;
1289                 name_proto = gnutls_protocol_get_name(gnutls_protocol_get_version(sess));
1290                 name_keyexchange = gnutls_kx_get_name(gnutls_kx_get(sess));
1291
1292                 return snprintf(buf, len, "%s-%s%15s Kx=%s      Enc=%s(%u) Mac=%s",
1293                         name_cipher, name_mac, name_proto, name_keyexchange, name_cipher, keysize, name_mac) > 0;
1294         }
1295         return false;
1296 #endif
1297 }
1298
1299 char *
1300 ConnSSL_GetCertFp(CONNECTION *c)
1301 {
1302         return c->ssl_state.fingerprint;
1303 }
1304
1305 bool
1306 ConnSSL_SetCertFp(CONNECTION *c, const char *fingerprint)
1307 {
1308         assert (c != NULL);
1309         c->ssl_state.fingerprint = strndup(fingerprint, SHA256_STRING_LEN - 1);
1310         return c->ssl_state.fingerprint != NULL;
1311 }
1312 #else
1313
1314 bool
1315 ConnSSL_InitLibrary(void)
1316 {
1317         return true;
1318 }
1319
1320 #endif /* SSL_SUPPORT */
1321 /* -eof- */