Annotation of ircnowd/src/ngircd/conn-ssl.c, Revision 1.1
1.1 ! tomglok 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:
! 47: static SSL_CTX * ssl_ctx;
! 48: static DH *dh_params;
! 49:
! 50: static bool ConnSSL_LoadServerKey_openssl PARAMS(( SSL_CTX *c ));
! 51: #endif
! 52:
! 53: #ifdef HAVE_LIBGNUTLS
! 54: #include <sys/types.h>
! 55: #include <sys/stat.h>
! 56: #include <fcntl.h>
! 57: #include <unistd.h>
! 58: #include <gnutls/x509.h>
! 59:
! 60: #define DH_BITS 2048
! 61: #define DH_BITS_MIN 1024
! 62:
! 63: #define MAX_HASH_SIZE 64 /* from gnutls-int.h */
! 64:
! 65: typedef struct {
! 66: int refcnt;
! 67: gnutls_certificate_credentials_t x509_cred;
! 68: gnutls_dh_params_t dh_params;
! 69: } x509_cred_slot;
! 70:
! 71: static array x509_creds = INIT_ARRAY;
! 72: static size_t x509_cred_idx;
! 73:
! 74: static gnutls_dh_params_t dh_params;
! 75: static gnutls_priority_t priorities_cache = NULL;
! 76: static bool ConnSSL_LoadServerKey_gnutls PARAMS(( void ));
! 77: #endif
! 78:
! 79: #define SHA256_STRING_LEN (32 * 2 + 1)
! 80:
! 81: static bool ConnSSL_Init_SSL PARAMS(( CONNECTION *c ));
! 82: static int ConnectAccept PARAMS(( CONNECTION *c, bool connect ));
! 83: static int ConnSSL_HandleError PARAMS(( CONNECTION *c, const int code, const char *fname ));
! 84:
! 85: #ifdef HAVE_LIBGNUTLS
! 86: static char * openreadclose(const char *name, size_t *len)
! 87: {
! 88: char *buf = NULL;
! 89: struct stat s;
! 90: ssize_t br;
! 91: int fd = open(name, O_RDONLY);
! 92: if (fd < 0) {
! 93: Log(LOG_ERR, "Could not open %s: %s", name, strerror(errno));
! 94: return NULL;
! 95: }
! 96: if (fstat(fd, &s)) {
! 97: Log(LOG_ERR, "Could not fstat %s: %s", name, strerror(errno));
! 98: goto out;
! 99: }
! 100: if (!S_ISREG(s.st_mode)) {
! 101: Log(LOG_ERR, "%s: Not a regular file", name);
! 102: goto out;
! 103: }
! 104: if (s.st_size <= 0) {
! 105: Log(LOG_ERR, "%s: invalid file length (size %ld <= 0)", name, (long) s.st_size);
! 106: goto out;
! 107: }
! 108: buf = malloc(s.st_size);
! 109: if (!buf) {
! 110: Log(LOG_ERR, "Could not malloc %lu bytes for file %s: %s", s.st_size, name, strerror(errno));
! 111: goto out;
! 112: }
! 113: br = read(fd, buf, s.st_size);
! 114: if (br != (ssize_t)s.st_size) {
! 115: Log(LOG_ERR, "Could not read file %s: read returned %ld, expected %ld: %s",
! 116: name, (long) br, (long) s.st_size, br == -1 ? strerror(errno):"short read?!");
! 117: memset(buf, 0, s.st_size);
! 118: free(buf);
! 119: buf = NULL;
! 120: } else {
! 121: *len = br;
! 122: }
! 123: out:
! 124: close(fd);
! 125: return buf;
! 126: }
! 127: #endif
! 128:
! 129:
! 130: #ifdef HAVE_LIBSSL
! 131: /**
! 132: * Log OpenSSL error message.
! 133: *
! 134: * @param msg The error message.
! 135: * @param info Additional information text or NULL.
! 136: */
! 137: static void
! 138: LogOpenSSLError(const char *error, const char *info)
! 139: {
! 140: unsigned long err = ERR_get_error();
! 141: char * errmsg = err
! 142: ? ERR_error_string(err, NULL)
! 143: : "Unable to determine error";
! 144:
! 145: assert(error != NULL);
! 146:
! 147: if (info)
! 148: Log(LOG_ERR, "%s: %s (%s)", error, info, errmsg);
! 149: else
! 150: Log(LOG_ERR, "%s: %s", error, errmsg);
! 151: }
! 152:
! 153:
! 154: static int
! 155: pem_passwd_cb(char *buf, int size, int rwflag, void *password)
! 156: {
! 157: array *pass = password;
! 158: int passlen;
! 159:
! 160: (void)rwflag; /* rwflag is unused if DEBUG is not set. */
! 161: assert(rwflag == 0); /* 0 -> callback used for decryption.
! 162: * See SSL_CTX_set_default_passwd_cb(3) */
! 163:
! 164: passlen = (int) array_bytes(pass);
! 165:
! 166: LogDebug("pem_passwd_cb buf size %d, array size %d", size, passlen);
! 167: assert(passlen >= 0);
! 168: if (passlen <= 0) {
! 169: Log(LOG_ERR, "PEM password required but not set [in pem_passwd_cb()]!");
! 170: return 0;
! 171: }
! 172: size = passlen > size ? size : passlen;
! 173: memcpy(buf, (char *)(array_start(pass)), size);
! 174: return size;
! 175: }
! 176:
! 177:
! 178: static int
! 179: Verify_openssl(UNUSED int preverify_ok, UNUSED X509_STORE_CTX *x509_ctx)
! 180: {
! 181: return 1;
! 182: }
! 183: #endif
! 184:
! 185:
! 186: static bool
! 187: Load_DH_params(void)
! 188: {
! 189: #ifdef HAVE_LIBSSL
! 190: FILE *fp;
! 191: bool ret = true;
! 192:
! 193: if (!Conf_SSLOptions.DHFile) {
! 194: Log(LOG_NOTICE, "Configuration option \"DHFile\" not set!");
! 195: return false;
! 196: }
! 197: fp = fopen(Conf_SSLOptions.DHFile, "r");
! 198: if (!fp) {
! 199: Log(LOG_ERR, "%s: %s", Conf_SSLOptions.DHFile, strerror(errno));
! 200: return false;
! 201: }
! 202: dh_params = PEM_read_DHparams(fp, NULL, NULL, NULL);
! 203: if (!dh_params) {
! 204: Log(LOG_ERR, "%s: Failed to read SSL DH parameters!",
! 205: Conf_SSLOptions.DHFile);
! 206: ret = false;
! 207: }
! 208: fclose(fp);
! 209: return ret;
! 210: #endif
! 211: #ifdef HAVE_LIBGNUTLS
! 212: bool need_dhgenerate = true;
! 213: int err;
! 214: gnutls_dh_params_t tmp_dh_params;
! 215:
! 216: err = gnutls_dh_params_init(&tmp_dh_params);
! 217: if (err < 0) {
! 218: Log(LOG_ERR, "Failed to initialize SSL DH parameters: %s",
! 219: gnutls_strerror(err));
! 220: return false;
! 221: }
! 222: if (Conf_SSLOptions.DHFile) {
! 223: gnutls_datum_t dhparms;
! 224: size_t size;
! 225: dhparms.data = (unsigned char *) openreadclose(Conf_SSLOptions.DHFile, &size);
! 226: if (dhparms.data) {
! 227: dhparms.size = size;
! 228: err = gnutls_dh_params_import_pkcs3(tmp_dh_params, &dhparms, GNUTLS_X509_FMT_PEM);
! 229: if (err == 0)
! 230: need_dhgenerate = false;
! 231: else
! 232: Log(LOG_ERR,
! 233: "Failed to initialize SSL DH parameters: %s",
! 234: gnutls_strerror(err));
! 235:
! 236: memset(dhparms.data, 0, size);
! 237: free(dhparms.data);
! 238: }
! 239: }
! 240: if (need_dhgenerate) {
! 241: Log(LOG_WARNING,
! 242: "DHFile not set, generating %u bit DH parameters. This may take a while ...",
! 243: DH_BITS);
! 244: err = gnutls_dh_params_generate2(tmp_dh_params, DH_BITS);
! 245: if (err < 0) {
! 246: Log(LOG_ERR, "Failed to generate SSL DH parameters: %s",
! 247: gnutls_strerror(err));
! 248: return false;
! 249: }
! 250: }
! 251: dh_params = tmp_dh_params;
! 252: return true;
! 253: #endif
! 254: }
! 255:
! 256:
! 257: void ConnSSL_Free(CONNECTION *c)
! 258: {
! 259: #ifdef HAVE_LIBSSL
! 260: SSL *ssl = c->ssl_state.ssl;
! 261: if (ssl) {
! 262: SSL_shutdown(ssl);
! 263: SSL_free(ssl);
! 264: c->ssl_state.ssl = NULL;
! 265: if (c->ssl_state.fingerprint) {
! 266: free(c->ssl_state.fingerprint);
! 267: c->ssl_state.fingerprint = NULL;
! 268: }
! 269: }
! 270: #endif
! 271: #ifdef HAVE_LIBGNUTLS
! 272: gnutls_session_t sess = c->ssl_state.gnutls_session;
! 273: if (Conn_OPTION_ISSET(c, CONN_SSL)) {
! 274: gnutls_bye(sess, GNUTLS_SHUT_RDWR);
! 275: gnutls_deinit(sess);
! 276: }
! 277: x509_cred_slot *slot = array_get(&x509_creds, sizeof(x509_cred_slot), c->ssl_state.x509_cred_idx);
! 278: assert(slot != NULL);
! 279: assert(slot->refcnt > 0);
! 280: assert(slot->x509_cred != NULL);
! 281: slot->refcnt--;
! 282: if ((c->ssl_state.x509_cred_idx != x509_cred_idx) && (slot->refcnt <= 0)) {
! 283: Log(LOG_INFO, "Discarding X509 certificate credentials from slot %zd.",
! 284: c->ssl_state.x509_cred_idx);
! 285: gnutls_certificate_free_keys(slot->x509_cred);
! 286: gnutls_certificate_free_credentials(slot->x509_cred);
! 287: slot->x509_cred = NULL;
! 288: gnutls_dh_params_deinit(slot->dh_params);
! 289: slot->dh_params = NULL;
! 290: slot->refcnt = 0;
! 291: }
! 292: #endif
! 293: assert(Conn_OPTION_ISSET(c, CONN_SSL));
! 294: /* can't just set bitmask to 0 -- there are other, non-ssl related flags, e.g. CONN_ZIP. */
! 295: Conn_OPTION_DEL(c, CONN_SSL_FLAGS_ALL);
! 296: }
! 297:
! 298:
! 299: bool
! 300: ConnSSL_InitLibrary( void )
! 301: {
! 302: if (!Conf_SSLInUse()) {
! 303: LogDebug("SSL not in use, skipping initialization.");
! 304: return true;
! 305: }
! 306:
! 307: #ifdef HAVE_LIBSSL
! 308: SSL_CTX *newctx;
! 309:
! 310: #if OPENSSL_API_COMPAT < 0x10100000L
! 311: if (!ssl_ctx) {
! 312: SSL_library_init();
! 313: SSL_load_error_strings();
! 314: }
! 315: #endif
! 316:
! 317: if (!RAND_status()) {
! 318: Log(LOG_ERR, "OpenSSL PRNG not seeded: /dev/urandom missing?");
! 319: /*
! 320: * it is probably best to fail and let the user install EGD or
! 321: * a similar program if no kernel random device is available.
! 322: * According to OpenSSL RAND_egd(3): "The automatic query of
! 323: * /var/run/egd-pool et al was added in OpenSSL 0.9.7";
! 324: * so it makes little sense to deal with PRNGD seeding ourselves.
! 325: */
! 326: array_free(&Conf_SSLOptions.ListenPorts);
! 327: return false;
! 328: }
! 329:
! 330: newctx = SSL_CTX_new(SSLv23_method());
! 331: if (!newctx) {
! 332: LogOpenSSLError("Failed to create SSL context", NULL);
! 333: array_free(&Conf_SSLOptions.ListenPorts);
! 334: return false;
! 335: }
! 336:
! 337: if (!ConnSSL_LoadServerKey_openssl(newctx)) {
! 338: /* Failed to read new key but an old ssl context
! 339: * already exists -> reuse old context */
! 340: if (ssl_ctx) {
! 341: SSL_CTX_free(newctx);
! 342: Log(LOG_WARNING,
! 343: "Re-Initializing of SSL failed, using old keys!");
! 344: return true;
! 345: }
! 346: /* No preexisting old context -> error. */
! 347: goto out;
! 348: }
! 349:
! 350: if (SSL_CTX_set_cipher_list(newctx, Conf_SSLOptions.CipherList) == 0) {
! 351: Log(LOG_ERR, "Failed to apply OpenSSL cipher list \"%s\"!",
! 352: Conf_SSLOptions.CipherList);
! 353: goto out;
! 354: }
! 355:
! 356: SSL_CTX_set_session_id_context(newctx, (unsigned char *)"ngircd", 6);
! 357: SSL_CTX_set_options(newctx, SSL_OP_SINGLE_DH_USE|SSL_OP_NO_SSLv2);
! 358: SSL_CTX_set_mode(newctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
! 359: SSL_CTX_set_verify(newctx, SSL_VERIFY_PEER|SSL_VERIFY_CLIENT_ONCE,
! 360: Verify_openssl);
! 361: SSL_CTX_free(ssl_ctx);
! 362: ssl_ctx = newctx;
! 363: Log(LOG_INFO, "%s initialized.", OpenSSL_version(OPENSSL_VERSION));
! 364: return true;
! 365: out:
! 366: SSL_CTX_free(newctx);
! 367: array_free(&Conf_SSLOptions.ListenPorts);
! 368: return false;
! 369: #endif
! 370: #ifdef HAVE_LIBGNUTLS
! 371: int err;
! 372: static bool initialized;
! 373:
! 374: if (!initialized) {
! 375: err = gnutls_global_init();
! 376: if (err) {
! 377: Log(LOG_ERR, "Failed to initialize GnuTLS: %s",
! 378: gnutls_strerror(err));
! 379: goto out;
! 380: }
! 381: }
! 382:
! 383: if (!ConnSSL_LoadServerKey_gnutls())
! 384: goto out;
! 385:
! 386: if (priorities_cache != NULL) {
! 387: gnutls_priority_deinit(priorities_cache);
! 388: }
! 389: if (gnutls_priority_init(&priorities_cache, Conf_SSLOptions.CipherList,
! 390: NULL) != GNUTLS_E_SUCCESS) {
! 391: Log(LOG_ERR,
! 392: "Failed to apply GnuTLS cipher list \"%s\"!",
! 393: Conf_SSLOptions.CipherList);
! 394: goto out;
! 395: }
! 396:
! 397: Log(LOG_INFO, "GnuTLS %s initialized.", gnutls_check_version(NULL));
! 398: initialized = true;
! 399: return true;
! 400: out:
! 401: array_free(&Conf_SSLOptions.ListenPorts);
! 402: return false;
! 403: #endif
! 404: }
! 405:
! 406:
! 407: #ifdef HAVE_LIBGNUTLS
! 408: static bool
! 409: ConnSSL_LoadServerKey_gnutls(void)
! 410: {
! 411: int err;
! 412: const char *cert_file;
! 413:
! 414: x509_cred_slot *slot = NULL;
! 415: gnutls_certificate_credentials_t x509_cred;
! 416:
! 417: err = gnutls_certificate_allocate_credentials(&x509_cred);
! 418: if (err < 0) {
! 419: Log(LOG_ERR, "Failed to allocate certificate credentials: %s",
! 420: gnutls_strerror(err));
! 421: return false;
! 422: }
! 423:
! 424: cert_file = Conf_SSLOptions.CertFile ? Conf_SSLOptions.CertFile:Conf_SSLOptions.KeyFile;
! 425: if (!cert_file) {
! 426: Log(LOG_ERR, "No SSL server key configured!");
! 427: return false;
! 428: }
! 429:
! 430: if (array_bytes(&Conf_SSLOptions.KeyFilePassword))
! 431: Log(LOG_WARNING,
! 432: "Ignoring SSL \"KeyFilePassword\": Not supported by GnuTLS.");
! 433:
! 434: if (!Load_DH_params())
! 435: return false;
! 436:
! 437: gnutls_certificate_set_dh_params(x509_cred, dh_params);
! 438: err = gnutls_certificate_set_x509_key_file(x509_cred, cert_file, Conf_SSLOptions.KeyFile, GNUTLS_X509_FMT_PEM);
! 439: if (err < 0) {
! 440: Log(LOG_ERR,
! 441: "Failed to set certificate key file (cert %s, key %s): %s",
! 442: cert_file,
! 443: Conf_SSLOptions.KeyFile ? Conf_SSLOptions.KeyFile : "(NULL)",
! 444: gnutls_strerror(err));
! 445: return false;
! 446: }
! 447:
! 448: /* Free currently active x509 context (if any) unless it is still in use */
! 449: slot = array_get(&x509_creds, sizeof(x509_cred_slot), x509_cred_idx);
! 450: if ((slot != NULL) && (slot->refcnt <= 0) && (slot->x509_cred != NULL)) {
! 451: Log(LOG_INFO, "Discarding X509 certificate credentials from slot %zd.", x509_cred_idx);
! 452: gnutls_certificate_free_keys(slot->x509_cred);
! 453: gnutls_certificate_free_credentials(slot->x509_cred);
! 454: slot->x509_cred = NULL;
! 455: gnutls_dh_params_deinit(slot->dh_params);
! 456: slot->dh_params = NULL;
! 457: slot->refcnt = 0;
! 458: }
! 459:
! 460: /* Find free slot */
! 461: x509_cred_idx = (size_t) -1;
! 462: size_t i;
! 463: for (slot = array_start(&x509_creds), i = 0;
! 464: i < array_length(&x509_creds, sizeof(x509_cred_slot));
! 465: slot++, i++) {
! 466: if (slot->refcnt <= 0) {
! 467: x509_cred_idx = i;
! 468: break;
! 469: }
! 470: }
! 471: /* ... allocate new slot otherwise. */
! 472: if (x509_cred_idx == (size_t) -1) {
! 473: x509_cred_idx = array_length(&x509_creds, sizeof(x509_cred_slot));
! 474: slot = array_alloc(&x509_creds, sizeof(x509_cred_slot), x509_cred_idx);
! 475: if (slot == NULL) {
! 476: Log(LOG_ERR, "Failed to allocate new slot for certificate credentials");
! 477: return false;
! 478: }
! 479: }
! 480: Log(LOG_INFO, "Storing new X509 certificate credentials in slot %zd.", x509_cred_idx);
! 481: slot->x509_cred = x509_cred;
! 482: slot->refcnt = 0;
! 483:
! 484: return true;
! 485: }
! 486: #endif
! 487:
! 488:
! 489: #ifdef HAVE_LIBSSL
! 490: static bool
! 491: ConnSSL_LoadServerKey_openssl(SSL_CTX *ctx)
! 492: {
! 493: char *cert_key;
! 494:
! 495: assert(ctx);
! 496: if (!Conf_SSLOptions.KeyFile) {
! 497: Log(LOG_ERR, "No SSL server key configured!");
! 498: return false;
! 499: }
! 500:
! 501: SSL_CTX_set_default_passwd_cb(ctx, pem_passwd_cb);
! 502: SSL_CTX_set_default_passwd_cb_userdata(ctx, &Conf_SSLOptions.KeyFilePassword);
! 503:
! 504: if (SSL_CTX_use_PrivateKey_file(ctx, Conf_SSLOptions.KeyFile, SSL_FILETYPE_PEM) != 1) {
! 505: array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
! 506: LogOpenSSLError("Failed to add private key", Conf_SSLOptions.KeyFile);
! 507: return false;
! 508: }
! 509:
! 510: cert_key = Conf_SSLOptions.CertFile ? Conf_SSLOptions.CertFile:Conf_SSLOptions.KeyFile;
! 511: if (SSL_CTX_use_certificate_chain_file(ctx, cert_key) != 1) {
! 512: array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
! 513: LogOpenSSLError("Failed to load certificate chain", cert_key);
! 514: return false;
! 515: }
! 516:
! 517: array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
! 518:
! 519: if (!SSL_CTX_check_private_key(ctx)) {
! 520: LogOpenSSLError("Server private key does not match certificate", NULL);
! 521: return false;
! 522: }
! 523: if (Load_DH_params()) {
! 524: if (SSL_CTX_set_tmp_dh(ctx, dh_params) != 1)
! 525: LogOpenSSLError("Error setting DH parameters", Conf_SSLOptions.DHFile);
! 526: /* don't return false here: the non-DH modes will still work */
! 527: DH_free(dh_params);
! 528: dh_params = NULL;
! 529: }
! 530: return true;
! 531: }
! 532:
! 533:
! 534: #endif
! 535: static bool
! 536: ConnSSL_Init_SSL(CONNECTION *c)
! 537: {
! 538: int ret;
! 539:
! 540: LogDebug("Initializing SSL ...");
! 541: assert(c != NULL);
! 542:
! 543: #ifdef HAVE_LIBSSL
! 544: if (!ssl_ctx) {
! 545: Log(LOG_ERR,
! 546: "Can't initialize SSL context, OpenSSL initialization failed at startup!");
! 547: return false;
! 548: }
! 549: assert(c->ssl_state.ssl == NULL);
! 550: assert(c->ssl_state.fingerprint == NULL);
! 551:
! 552: c->ssl_state.ssl = SSL_new(ssl_ctx);
! 553: if (!c->ssl_state.ssl) {
! 554: LogOpenSSLError("Failed to create SSL structure", NULL);
! 555: return false;
! 556: }
! 557: Conn_OPTION_ADD(c, CONN_SSL);
! 558:
! 559: ret = SSL_set_fd(c->ssl_state.ssl, c->sock);
! 560: if (ret != 1) {
! 561: LogOpenSSLError("Failed to set SSL file descriptor", NULL);
! 562: ConnSSL_Free(c);
! 563: return false;
! 564: }
! 565: #endif
! 566: #ifdef HAVE_LIBGNUTLS
! 567: Conn_OPTION_ADD(c, CONN_SSL);
! 568: ret = gnutls_priority_set(c->ssl_state.gnutls_session, priorities_cache);
! 569: if (ret != GNUTLS_E_SUCCESS) {
! 570: Log(LOG_ERR, "Failed to set GnuTLS session priorities: %s",
! 571: gnutls_strerror(ret));
! 572: ConnSSL_Free(c);
! 573: return false;
! 574: }
! 575: /*
! 576: * The intermediate (long) cast is here to avoid a warning like:
! 577: * "cast to pointer from integer of different size" on 64-bit platforms.
! 578: * There doesn't seem to be an alternate GNUTLS API we could use instead, see e.g.
! 579: * http://www.mail-archive.com/help-gnutls@gnu.org/msg00286.html
! 580: */
! 581: gnutls_transport_set_ptr(c->ssl_state.gnutls_session,
! 582: (gnutls_transport_ptr_t) (long) c->sock);
! 583: gnutls_certificate_server_set_request(c->ssl_state.gnutls_session,
! 584: GNUTLS_CERT_REQUEST);
! 585:
! 586: Log(LOG_INFO, "Using X509 credentials from slot %zd", x509_cred_idx);
! 587: c->ssl_state.x509_cred_idx = x509_cred_idx;
! 588: x509_cred_slot *slot = array_get(&x509_creds, sizeof(x509_cred_slot), x509_cred_idx);
! 589: slot->refcnt++;
! 590: ret = gnutls_credentials_set(c->ssl_state.gnutls_session,
! 591: GNUTLS_CRD_CERTIFICATE, slot->x509_cred);
! 592: if (ret != 0) {
! 593: Log(LOG_ERR, "Failed to set SSL credentials: %s",
! 594: gnutls_strerror(ret));
! 595: ConnSSL_Free(c);
! 596: return false;
! 597: }
! 598: gnutls_dh_set_prime_bits(c->ssl_state.gnutls_session, DH_BITS_MIN);
! 599: #endif
! 600: return true;
! 601: }
! 602:
! 603:
! 604: bool
! 605: ConnSSL_PrepareConnect(CONNECTION *c, UNUSED CONF_SERVER *s)
! 606: {
! 607: bool ret;
! 608: #ifdef HAVE_LIBGNUTLS
! 609: int err;
! 610:
! 611: err = gnutls_init(&c->ssl_state.gnutls_session, GNUTLS_CLIENT);
! 612: if (err) {
! 613: Log(LOG_ERR, "Failed to initialize new SSL session: %s",
! 614: gnutls_strerror(err));
! 615: return false;
! 616: }
! 617: #endif
! 618: ret = ConnSSL_Init_SSL(c);
! 619: if (!ret)
! 620: return false;
! 621: Conn_OPTION_ADD(c, CONN_SSL_CONNECT);
! 622: #ifdef HAVE_LIBSSL
! 623: assert(c->ssl_state.ssl);
! 624: SSL_set_verify(c->ssl_state.ssl, SSL_VERIFY_NONE, NULL);
! 625: #endif
! 626: return true;
! 627: }
! 628:
! 629:
! 630: /**
! 631: * Check and handle error return codes after failed calls to SSL functions.
! 632: *
! 633: * OpenSSL:
! 634: * SSL_connect(), SSL_accept(), SSL_do_handshake(), SSL_read(), SSL_peek(), or
! 635: * SSL_write() on ssl.
! 636: *
! 637: * GnuTLS:
! 638: * gnutlsssl_read(), gnutls_write() or gnutls_handshake().
! 639: *
! 640: * @param c The connection handle.
! 641: * @prarm code The return code.
! 642: * @param fname The name of the function in which the error occurred.
! 643: * @return -1 on fatal errors, 0 if we can try again later.
! 644: */
! 645: static int
! 646: ConnSSL_HandleError(CONNECTION * c, const int code, const char *fname)
! 647: {
! 648: #ifdef HAVE_LIBSSL
! 649: int ret = SSL_ERROR_SYSCALL;
! 650: unsigned long sslerr;
! 651: int real_errno = errno;
! 652:
! 653: ret = SSL_get_error(c->ssl_state.ssl, code);
! 654:
! 655: switch (ret) {
! 656: case SSL_ERROR_WANT_READ:
! 657: io_event_del(c->sock, IO_WANTWRITE);
! 658: Conn_OPTION_ADD(c, CONN_SSL_WANT_READ);
! 659: return 0; /* try again later */
! 660: case SSL_ERROR_WANT_WRITE:
! 661: io_event_del(c->sock, IO_WANTREAD);
! 662: Conn_OPTION_ADD(c, CONN_SSL_WANT_WRITE); /* fall through */
! 663: case SSL_ERROR_NONE:
! 664: return 0; /* try again later */
! 665: case SSL_ERROR_ZERO_RETURN:
! 666: LogDebug("SSL connection shut down normally.");
! 667: break;
! 668: case SSL_ERROR_SYSCALL:
! 669: /* SSL_ERROR_WANT_CONNECT, SSL_ERROR_WANT_ACCEPT,
! 670: * and SSL_ERROR_WANT_X509_LOOKUP */
! 671: sslerr = ERR_get_error();
! 672: if (sslerr) {
! 673: Log(LOG_ERR, "SSL error: %s [in %s()]!",
! 674: ERR_error_string(sslerr, NULL), fname);
! 675: } else {
! 676: switch (code) { /* EOF that violated protocol */
! 677: case 0:
! 678: Log(LOG_ERR,
! 679: "SSL error, client disconnected [in %s()]!",
! 680: fname);
! 681: break;
! 682: case -1: /* low level socket I/O error, check errno */
! 683: Log(LOG_ERR, "SSL error: %s [in %s()]!",
! 684: strerror(real_errno), fname);
! 685: }
! 686: }
! 687: break;
! 688: case SSL_ERROR_SSL:
! 689: LogOpenSSLError("SSL protocol error", fname);
! 690: break;
! 691: default:
! 692: Log(LOG_ERR, "Unknown SSL error %d [in %s()]!", ret, fname);
! 693: }
! 694: ConnSSL_Free(c);
! 695: return -1;
! 696: #endif
! 697: #ifdef HAVE_LIBGNUTLS
! 698: switch (code) {
! 699: case GNUTLS_E_AGAIN:
! 700: case GNUTLS_E_INTERRUPTED:
! 701: if (gnutls_record_get_direction(c->ssl_state.gnutls_session)) {
! 702: Conn_OPTION_ADD(c, CONN_SSL_WANT_WRITE);
! 703: io_event_del(c->sock, IO_WANTREAD);
! 704: } else {
! 705: Conn_OPTION_ADD(c, CONN_SSL_WANT_READ);
! 706: io_event_del(c->sock, IO_WANTWRITE);
! 707: }
! 708: break;
! 709: default:
! 710: assert(code < 0);
! 711: if (gnutls_error_is_fatal(code)) {
! 712: Log(LOG_ERR, "SSL error: %s [%s].",
! 713: gnutls_strerror(code), fname);
! 714: ConnSSL_Free(c);
! 715: return -1;
! 716: }
! 717: }
! 718: return 0;
! 719: #endif
! 720: }
! 721:
! 722:
! 723: static void
! 724: ConnSSL_LogCertInfo( CONNECTION *c )
! 725: {
! 726: #ifdef HAVE_LIBSSL
! 727: SSL *ssl = c->ssl_state.ssl;
! 728:
! 729: assert(ssl);
! 730:
! 731: Log(LOG_INFO, "Connection %d: initialized %s using cipher %s.",
! 732: c->sock, SSL_get_version(ssl), SSL_get_cipher(ssl));
! 733: #endif
! 734: #ifdef HAVE_LIBGNUTLS
! 735: gnutls_session_t sess = c->ssl_state.gnutls_session;
! 736: gnutls_cipher_algorithm_t cipher = gnutls_cipher_get(sess);
! 737:
! 738: Log(LOG_INFO, "Connection %d: initialized %s using cipher %s-%s.",
! 739: c->sock,
! 740: gnutls_protocol_get_name(gnutls_protocol_get_version(sess)),
! 741: gnutls_cipher_get_name(cipher),
! 742: gnutls_mac_get_name(gnutls_mac_get(sess)));
! 743: #endif
! 744: }
! 745:
! 746:
! 747: /*
! 748: Accept incoming SSL connection.
! 749: Return Values:
! 750: 1: SSL Connection established
! 751: 0: try again
! 752: -1: SSL Connection not established due to fatal error.
! 753: */
! 754: int
! 755: ConnSSL_Accept( CONNECTION *c )
! 756: {
! 757: assert(c != NULL);
! 758: if (!Conn_OPTION_ISSET(c, CONN_SSL)) {
! 759: #ifdef HAVE_LIBGNUTLS
! 760: int err = gnutls_init(&c->ssl_state.gnutls_session, GNUTLS_SERVER);
! 761: if (err) {
! 762: Log(LOG_ERR, "Failed to initialize new SSL session: %s",
! 763: gnutls_strerror(err));
! 764: return false;
! 765: }
! 766: #endif
! 767: if (!ConnSSL_Init_SSL(c))
! 768: return -1;
! 769: }
! 770: return ConnectAccept(c, false );
! 771: }
! 772:
! 773:
! 774: int
! 775: ConnSSL_Connect( CONNECTION *c )
! 776: {
! 777: assert(c != NULL);
! 778: #ifdef HAVE_LIBSSL
! 779: assert(c->ssl_state.ssl);
! 780: #endif
! 781: assert(Conn_OPTION_ISSET(c, CONN_SSL));
! 782: return ConnectAccept(c, true);
! 783: }
! 784:
! 785: static int
! 786: ConnSSL_InitCertFp( CONNECTION *c )
! 787: {
! 788: const char hex[] = "0123456789abcdef";
! 789: int i;
! 790:
! 791: #ifdef HAVE_LIBSSL
! 792: unsigned char digest[EVP_MAX_MD_SIZE];
! 793: unsigned int digest_size;
! 794: X509 *cert;
! 795:
! 796: cert = SSL_get_peer_certificate(c->ssl_state.ssl);
! 797: if (!cert)
! 798: return 0;
! 799:
! 800: if (!X509_digest(cert, EVP_sha256(), digest, &digest_size)) {
! 801: X509_free(cert);
! 802: return 0;
! 803: }
! 804:
! 805: X509_free(cert);
! 806: #endif /* HAVE_LIBSSL */
! 807: #ifdef HAVE_LIBGNUTLS
! 808: gnutls_x509_crt_t cert;
! 809: unsigned int cert_list_size;
! 810: const gnutls_datum_t *cert_list;
! 811: unsigned char digest[MAX_HASH_SIZE];
! 812: size_t digest_size;
! 813:
! 814: if (gnutls_certificate_type_get(c->ssl_state.gnutls_session) !=
! 815: GNUTLS_CRT_X509)
! 816: return 0;
! 817:
! 818: if (gnutls_x509_crt_init(&cert) != GNUTLS_E_SUCCESS)
! 819: return 0;
! 820:
! 821: cert_list_size = 0;
! 822: cert_list = gnutls_certificate_get_peers(c->ssl_state.gnutls_session,
! 823: &cert_list_size);
! 824: if (!cert_list) {
! 825: gnutls_x509_crt_deinit(cert);
! 826: return 0;
! 827: }
! 828:
! 829: if (gnutls_x509_crt_import(cert, &cert_list[0],
! 830: GNUTLS_X509_FMT_DER) != GNUTLS_E_SUCCESS) {
! 831: gnutls_x509_crt_deinit(cert);
! 832: return 0;
! 833: }
! 834:
! 835: digest_size = sizeof(digest);
! 836: if (gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_SHA256, digest,
! 837: &digest_size)) {
! 838: gnutls_x509_crt_deinit(cert);
! 839: return 0;
! 840: }
! 841:
! 842: gnutls_x509_crt_deinit(cert);
! 843: #endif /* HAVE_LIBGNUTLS */
! 844:
! 845: assert(c->ssl_state.fingerprint == NULL);
! 846:
! 847: c->ssl_state.fingerprint = malloc(SHA256_STRING_LEN);
! 848: if (!c->ssl_state.fingerprint)
! 849: return 0;
! 850:
! 851: for (i = 0; i < (int)digest_size; i++) {
! 852: c->ssl_state.fingerprint[i * 2] = hex[digest[i] / 16];
! 853: c->ssl_state.fingerprint[i * 2 + 1] = hex[digest[i] % 16];
! 854: }
! 855: c->ssl_state.fingerprint[i * 2] = '\0';
! 856:
! 857: return 1;
! 858: }
! 859:
! 860: /* accept/connect wrapper. if connect is true, connect to peer, otherwise wait for incoming connection */
! 861: static int
! 862: ConnectAccept( CONNECTION *c, bool connect)
! 863: {
! 864: int ret;
! 865: #ifdef HAVE_LIBSSL
! 866: SSL *ssl = c->ssl_state.ssl;
! 867: assert(ssl != NULL);
! 868:
! 869: ret = connect ? SSL_connect(ssl) : SSL_accept(ssl);
! 870: if (1 != ret)
! 871: return ConnSSL_HandleError(c, ret, connect ? "SSL_connect": "SSL_accept");
! 872: #endif
! 873: #ifdef HAVE_LIBGNUTLS
! 874: (void) connect;
! 875: ret = gnutls_handshake(c->ssl_state.gnutls_session);
! 876: if (ret)
! 877: return ConnSSL_HandleError(c, ret, "gnutls_handshake");
! 878: #endif /* _GNUTLS */
! 879: (void)ConnSSL_InitCertFp(c);
! 880:
! 881: Conn_OPTION_DEL(c, (CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ|CONN_SSL_CONNECT));
! 882: ConnSSL_LogCertInfo(c);
! 883:
! 884: Conn_StartLogin(CONNECTION2ID(c));
! 885: return 1;
! 886: }
! 887:
! 888:
! 889: ssize_t
! 890: ConnSSL_Write(CONNECTION *c, const void *buf, size_t count)
! 891: {
! 892: ssize_t bw;
! 893:
! 894: Conn_OPTION_DEL(c, CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ);
! 895:
! 896: assert(count > 0);
! 897: #ifdef HAVE_LIBSSL
! 898: bw = (ssize_t) SSL_write(c->ssl_state.ssl, buf, count);
! 899: #endif
! 900: #ifdef HAVE_LIBGNUTLS
! 901: bw = gnutls_write(c->ssl_state.gnutls_session, buf, count);
! 902: #endif
! 903: if (bw > 0)
! 904: return bw;
! 905: if (ConnSSL_HandleError( c, bw, "ConnSSL_Write") == 0)
! 906: errno = EAGAIN; /* try again */
! 907: return -1;
! 908: }
! 909:
! 910:
! 911: ssize_t
! 912: ConnSSL_Read(CONNECTION *c, void * buf, size_t count)
! 913: {
! 914: ssize_t br;
! 915:
! 916: Conn_OPTION_DEL(c, CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ);
! 917: #ifdef HAVE_LIBSSL
! 918: br = (ssize_t) SSL_read(c->ssl_state.ssl, buf, count);
! 919: if (br > 0) /* on EOF we have to call ConnSSL_HandleError(), see SSL_read(3) */
! 920: return br;
! 921: #endif
! 922: #ifdef HAVE_LIBGNUTLS
! 923: br = gnutls_read(c->ssl_state.gnutls_session, buf, count);
! 924: if (br >= 0) /* on EOF we must _not_ call ConnSSL_HandleError, see gnutls_record_recv(3) */
! 925: return br;
! 926: #endif
! 927: /* error on read: switch ConnSSL_HandleError() return values -> 0 is "try again", so return -1 and set EAGAIN */
! 928: if (ConnSSL_HandleError(c, br, "ConnSSL_Read") == 0) {
! 929: errno = EAGAIN;
! 930: return -1;
! 931: }
! 932: return 0;
! 933: }
! 934:
! 935:
! 936: bool
! 937: ConnSSL_GetCipherInfo(CONNECTION *c, char *buf, size_t len)
! 938: {
! 939: #ifdef HAVE_LIBSSL
! 940: char *nl;
! 941: SSL *ssl = c->ssl_state.ssl;
! 942:
! 943: if (!ssl)
! 944: return false;
! 945: *buf = 0;
! 946: SSL_CIPHER_description(SSL_get_current_cipher(ssl), buf, len);
! 947: nl = strchr(buf, '\n');
! 948: if (nl)
! 949: *nl = 0;
! 950: return true;
! 951: #endif
! 952: #ifdef HAVE_LIBGNUTLS
! 953: if (Conn_OPTION_ISSET(c, CONN_SSL)) {
! 954: const char *name_cipher, *name_mac, *name_proto, *name_keyexchange;
! 955: unsigned keysize;
! 956:
! 957: gnutls_session_t sess = c->ssl_state.gnutls_session;
! 958: gnutls_cipher_algorithm_t cipher = gnutls_cipher_get(sess);
! 959: name_cipher = gnutls_cipher_get_name(cipher);
! 960: name_mac = gnutls_mac_get_name(gnutls_mac_get(sess));
! 961: keysize = gnutls_cipher_get_key_size(cipher) * 8;
! 962: name_proto = gnutls_protocol_get_name(gnutls_protocol_get_version(sess));
! 963: name_keyexchange = gnutls_kx_get_name(gnutls_kx_get(sess));
! 964:
! 965: return snprintf(buf, len, "%s-%s%15s Kx=%s Enc=%s(%u) Mac=%s",
! 966: name_cipher, name_mac, name_proto, name_keyexchange, name_cipher, keysize, name_mac) > 0;
! 967: }
! 968: return false;
! 969: #endif
! 970: }
! 971:
! 972: char *
! 973: ConnSSL_GetCertFp(CONNECTION *c)
! 974: {
! 975: return c->ssl_state.fingerprint;
! 976: }
! 977:
! 978: bool
! 979: ConnSSL_SetCertFp(CONNECTION *c, const char *fingerprint)
! 980: {
! 981: assert (c != NULL);
! 982: c->ssl_state.fingerprint = strndup(fingerprint, SHA256_STRING_LEN - 1);
! 983: return c->ssl_state.fingerprint != NULL;
! 984: }
! 985: #else
! 986:
! 987: bool
! 988: ConnSSL_InitLibrary(void)
! 989: {
! 990: return true;
! 991: }
! 992:
! 993: #endif /* SSL_SUPPORT */
! 994: /* -eof- */
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