2 * ngIRCd -- The Next Generation IRC Daemon
3 * Copyright (c) 2005-2008 Florian Westphal <fw@strlen.de>
10 * SSL wrapper functions
27 #include "conn-func.h"
33 extern struct SSLOptions Conf_SSLOptions;
36 #include <openssl/err.h>
37 #include <openssl/rand.h>
39 static SSL_CTX * ssl_ctx;
42 static bool ConnSSL_LoadServerKey_openssl PARAMS(( SSL_CTX *c ));
46 #include <sys/types.h>
50 #include <gnutls/x509.h>
53 #define DH_BITS_MIN 1024
55 #define MAX_HASH_SIZE 64 /* from gnutls-int.h */
57 static gnutls_certificate_credentials_t x509_cred;
58 static gnutls_dh_params_t dh_params;
59 static gnutls_priority_t priorities_cache;
60 static bool ConnSSL_LoadServerKey_gnutls PARAMS(( void ));
63 #define SHA256_STRING_LEN (32 * 2 + 1)
65 static bool ConnSSL_Init_SSL PARAMS(( CONNECTION *c ));
66 static int ConnectAccept PARAMS(( CONNECTION *c, bool connect ));
67 static int ConnSSL_HandleError PARAMS(( CONNECTION *c, const int code, const char *fname ));
70 static char * openreadclose(const char *name, size_t *len)
75 int fd = open(name, O_RDONLY);
77 Log(LOG_ERR, "Could not open %s: %s", name, strerror(errno));
81 Log(LOG_ERR, "Could not fstat %s: %s", name, strerror(errno));
84 if (!S_ISREG(s.st_mode)) {
85 Log(LOG_ERR, "%s: Not a regular file", name);
89 Log(LOG_ERR, "%s: invalid file length (size %ld <= 0)", name, (long) s.st_size);
92 buf = malloc(s.st_size);
94 Log(LOG_ERR, "Could not malloc %lu bytes for file %s: %s", s.st_size, name, strerror(errno));
97 br = read(fd, buf, s.st_size);
98 if (br != (ssize_t)s.st_size) {
99 Log(LOG_ERR, "Could not read file %s: read returned %ld, expected %ld: %s",
100 name, (long) br, (long) s.st_size, br == -1 ? strerror(errno):"short read?!");
101 memset(buf, 0, s.st_size);
116 * Log OpenSSL error message.
118 * @param msg The error message.
119 * @param info Additional information text or NULL.
122 LogOpenSSLError(const char *error, const char *info)
124 unsigned long err = ERR_get_error();
126 ? ERR_error_string(err, NULL)
127 : "Unable to determine error";
129 assert(error != NULL);
132 Log(LOG_ERR, "%s: %s (%s)", error, info, errmsg);
134 Log(LOG_ERR, "%s: %s", error, errmsg);
139 pem_passwd_cb(char *buf, int size, int rwflag, void *password)
141 array *pass = password;
144 (void)rwflag; /* rwflag is unused if DEBUG is not set. */
145 assert(rwflag == 0); /* 0 -> callback used for decryption.
146 * See SSL_CTX_set_default_passwd_cb(3) */
148 passlen = (int) array_bytes(pass);
150 LogDebug("pem_passwd_cb buf size %d, array size %d", size, passlen);
151 assert(passlen >= 0);
153 Log(LOG_ERR, "PEM password required but not set [in pem_passwd_cb()]!");
156 size = passlen > size ? size : passlen;
157 memcpy(buf, (char *)(array_start(pass)), size);
163 Verify_openssl(UNUSED int preverify_ok, UNUSED X509_STORE_CTX *x509_ctx)
177 if (!Conf_SSLOptions.DHFile) {
178 Log(LOG_NOTICE, "Configuration option \"DHFile\" not set!");
181 fp = fopen(Conf_SSLOptions.DHFile, "r");
183 Log(LOG_ERR, "%s: %s", Conf_SSLOptions.DHFile, strerror(errno));
186 dh_params = PEM_read_DHparams(fp, NULL, NULL, NULL);
188 Log(LOG_ERR, "%s: Failed to read SSL DH parameters!",
189 Conf_SSLOptions.DHFile);
195 #ifdef HAVE_LIBGNUTLS
196 bool need_dhgenerate = true;
198 gnutls_dh_params_t tmp_dh_params;
200 err = gnutls_dh_params_init(&tmp_dh_params);
202 Log(LOG_ERR, "Failed to initialize SSL DH parameters: %s",
203 gnutls_strerror(err));
206 if (Conf_SSLOptions.DHFile) {
207 gnutls_datum_t dhparms;
209 dhparms.data = (unsigned char *) openreadclose(Conf_SSLOptions.DHFile, &size);
212 err = gnutls_dh_params_import_pkcs3(tmp_dh_params, &dhparms, GNUTLS_X509_FMT_PEM);
214 need_dhgenerate = false;
217 "Failed to initialize SSL DH parameters: %s",
218 gnutls_strerror(err));
220 memset(dhparms.data, 0, size);
224 if (need_dhgenerate) {
226 "DHFile not set, generating %u bit DH parameters. This may take a while ...",
228 err = gnutls_dh_params_generate2(tmp_dh_params, DH_BITS);
230 Log(LOG_ERR, "Failed to generate SSL DH parameters: %s",
231 gnutls_strerror(err));
235 dh_params = tmp_dh_params;
241 void ConnSSL_Free(CONNECTION *c)
244 SSL *ssl = c->ssl_state.ssl;
248 c->ssl_state.ssl = NULL;
249 if (c->ssl_state.fingerprint) {
250 free(c->ssl_state.fingerprint);
251 c->ssl_state.fingerprint = NULL;
255 #ifdef HAVE_LIBGNUTLS
256 gnutls_session_t sess = c->ssl_state.gnutls_session;
257 if (Conn_OPTION_ISSET(c, CONN_SSL)) {
258 gnutls_bye(sess, GNUTLS_SHUT_RDWR);
262 assert(Conn_OPTION_ISSET(c, CONN_SSL));
263 /* can't just set bitmask to 0 -- there are other, non-ssl related flags, e.g. CONN_ZIP. */
264 Conn_OPTION_DEL(c, CONN_SSL_FLAGS_ALL);
269 ConnSSL_InitLibrary( void )
271 if (!Conf_SSLInUse()) {
272 LogDebug("SSL not in use, skipping initialization.");
281 SSL_load_error_strings();
284 if (!RAND_status()) {
285 Log(LOG_ERR, "OpenSSL PRNG not seeded: /dev/urandom missing?");
287 * it is probably best to fail and let the user install EGD or
288 * a similar program if no kernel random device is available.
289 * According to OpenSSL RAND_egd(3): "The automatic query of
290 * /var/run/egd-pool et al was added in OpenSSL 0.9.7";
291 * so it makes little sense to deal with PRNGD seeding ourselves.
293 array_free(&Conf_SSLOptions.ListenPorts);
297 newctx = SSL_CTX_new(SSLv23_method());
299 LogOpenSSLError("Failed to create SSL context", NULL);
300 array_free(&Conf_SSLOptions.ListenPorts);
304 if (!ConnSSL_LoadServerKey_openssl(newctx))
307 if (SSL_CTX_set_cipher_list(newctx, Conf_SSLOptions.CipherList) == 0) {
308 Log(LOG_ERR, "Failed to apply OpenSSL cipher list \"%s\"!",
309 Conf_SSLOptions.CipherList);
313 SSL_CTX_set_options(newctx, SSL_OP_SINGLE_DH_USE|SSL_OP_NO_SSLv2);
314 SSL_CTX_set_mode(newctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
315 SSL_CTX_set_verify(newctx, SSL_VERIFY_PEER|SSL_VERIFY_CLIENT_ONCE,
317 SSL_CTX_free(ssl_ctx);
319 Log(LOG_INFO, "%s initialized.", SSLeay_version(SSLEAY_VERSION));
322 SSL_CTX_free(newctx);
323 array_free(&Conf_SSLOptions.ListenPorts);
326 #ifdef HAVE_LIBGNUTLS
328 static bool initialized;
331 /* TODO: cannot reload gnutls keys: can't simply free x509
332 * context -- it may still be in use */
336 err = gnutls_global_init();
338 Log(LOG_ERR, "Failed to initialize GnuTLS: %s",
339 gnutls_strerror(err));
343 if (!ConnSSL_LoadServerKey_gnutls())
346 if (gnutls_priority_init(&priorities_cache, Conf_SSLOptions.CipherList,
347 NULL) != GNUTLS_E_SUCCESS) {
349 "Failed to apply GnuTLS cipher list \"%s\"!",
350 Conf_SSLOptions.CipherList);
354 Log(LOG_INFO, "GnuTLS %s initialized.", gnutls_check_version(NULL));
358 array_free(&Conf_SSLOptions.ListenPorts);
364 #ifdef HAVE_LIBGNUTLS
366 ConnSSL_LoadServerKey_gnutls(void)
369 const char *cert_file;
371 err = gnutls_certificate_allocate_credentials(&x509_cred);
373 Log(LOG_ERR, "Failed to allocate certificate credentials: %s",
374 gnutls_strerror(err));
378 cert_file = Conf_SSLOptions.CertFile ? Conf_SSLOptions.CertFile:Conf_SSLOptions.KeyFile;
380 Log(LOG_ERR, "No SSL server key configured!");
384 if (array_bytes(&Conf_SSLOptions.KeyFilePassword))
386 "Ignoring SSL \"KeyFilePassword\": Not supported by GnuTLS.");
388 if (!Load_DH_params())
391 gnutls_certificate_set_dh_params(x509_cred, dh_params);
392 err = gnutls_certificate_set_x509_key_file(x509_cred, cert_file, Conf_SSLOptions.KeyFile, GNUTLS_X509_FMT_PEM);
395 "Failed to set certificate key file (cert %s, key %s): %s",
397 Conf_SSLOptions.KeyFile ? Conf_SSLOptions.KeyFile : "(NULL)",
398 gnutls_strerror(err));
408 ConnSSL_LoadServerKey_openssl(SSL_CTX *ctx)
413 if (!Conf_SSLOptions.KeyFile) {
414 Log(LOG_ERR, "No SSL server key configured!");
418 SSL_CTX_set_default_passwd_cb(ctx, pem_passwd_cb);
419 SSL_CTX_set_default_passwd_cb_userdata(ctx, &Conf_SSLOptions.KeyFilePassword);
421 if (SSL_CTX_use_PrivateKey_file(ctx, Conf_SSLOptions.KeyFile, SSL_FILETYPE_PEM) != 1) {
422 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
423 LogOpenSSLError("Failed to add private key", Conf_SSLOptions.KeyFile);
427 cert_key = Conf_SSLOptions.CertFile ? Conf_SSLOptions.CertFile:Conf_SSLOptions.KeyFile;
428 if (SSL_CTX_use_certificate_chain_file(ctx, cert_key) != 1) {
429 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
430 LogOpenSSLError("Failed to load certificate chain", cert_key);
434 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
436 if (!SSL_CTX_check_private_key(ctx)) {
437 LogOpenSSLError("Server private key does not match certificate", NULL);
440 if (Load_DH_params()) {
441 if (SSL_CTX_set_tmp_dh(ctx, dh_params) != 1)
442 LogOpenSSLError("Error setting DH parameters", Conf_SSLOptions.DHFile);
443 /* don't return false here: the non-DH modes will still work */
453 ConnSSL_Init_SSL(CONNECTION *c)
457 LogDebug("Initializing SSL ...");
463 "Can't initialize SSL context, OpenSSL initialization failed at startup!");
466 assert(c->ssl_state.ssl == NULL);
467 assert(c->ssl_state.fingerprint == NULL);
469 c->ssl_state.ssl = SSL_new(ssl_ctx);
470 if (!c->ssl_state.ssl) {
471 LogOpenSSLError("Failed to create SSL structure", NULL);
474 Conn_OPTION_ADD(c, CONN_SSL);
476 ret = SSL_set_fd(c->ssl_state.ssl, c->sock);
478 LogOpenSSLError("Failed to set SSL file descriptor", NULL);
483 #ifdef HAVE_LIBGNUTLS
484 Conn_OPTION_ADD(c, CONN_SSL);
485 ret = gnutls_priority_set(c->ssl_state.gnutls_session, priorities_cache);
486 if (ret != GNUTLS_E_SUCCESS) {
487 Log(LOG_ERR, "Failed to set GnuTLS session priorities: %s",
488 gnutls_strerror(ret));
493 * The intermediate (long) cast is here to avoid a warning like:
494 * "cast to pointer from integer of different size" on 64-bit platforms.
495 * There doesn't seem to be an alternate GNUTLS API we could use instead, see e.g.
496 * http://www.mail-archive.com/help-gnutls@gnu.org/msg00286.html
498 gnutls_transport_set_ptr(c->ssl_state.gnutls_session,
499 (gnutls_transport_ptr_t) (long) c->sock);
500 gnutls_certificate_server_set_request(c->ssl_state.gnutls_session,
501 GNUTLS_CERT_REQUEST);
502 ret = gnutls_credentials_set(c->ssl_state.gnutls_session,
503 GNUTLS_CRD_CERTIFICATE, x509_cred);
505 Log(LOG_ERR, "Failed to set SSL credentials: %s",
506 gnutls_strerror(ret));
510 gnutls_dh_set_prime_bits(c->ssl_state.gnutls_session, DH_BITS_MIN);
517 ConnSSL_PrepareConnect(CONNECTION *c, UNUSED CONF_SERVER *s)
520 #ifdef HAVE_LIBGNUTLS
523 err = gnutls_init(&c->ssl_state.gnutls_session, GNUTLS_CLIENT);
525 Log(LOG_ERR, "Failed to initialize new SSL session: %s",
526 gnutls_strerror(err));
530 ret = ConnSSL_Init_SSL(c);
533 Conn_OPTION_ADD(c, CONN_SSL_CONNECT);
535 assert(c->ssl_state.ssl);
536 SSL_set_verify(c->ssl_state.ssl, SSL_VERIFY_NONE, NULL);
543 * Check and handle error return codes after failed calls to SSL functions.
546 * SSL_connect(), SSL_accept(), SSL_do_handshake(), SSL_read(), SSL_peek(), or
547 * SSL_write() on ssl.
550 * gnutlsssl_read(), gnutls_write() or gnutls_handshake().
552 * @param c The connection handle.
553 * @prarm code The return code.
554 * @param fname The name of the function in which the error occurred.
555 * @return -1 on fatal errors, 0 if we can try again later.
558 ConnSSL_HandleError(CONNECTION * c, const int code, const char *fname)
561 int ret = SSL_ERROR_SYSCALL;
562 unsigned long sslerr;
563 int real_errno = errno;
565 ret = SSL_get_error(c->ssl_state.ssl, code);
568 case SSL_ERROR_WANT_READ:
569 io_event_del(c->sock, IO_WANTWRITE);
570 Conn_OPTION_ADD(c, CONN_SSL_WANT_READ);
571 return 0; /* try again later */
572 case SSL_ERROR_WANT_WRITE:
573 io_event_del(c->sock, IO_WANTREAD);
574 Conn_OPTION_ADD(c, CONN_SSL_WANT_WRITE); /* fall through */
576 return 0; /* try again later */
577 case SSL_ERROR_ZERO_RETURN:
578 LogDebug("SSL connection shut down normally.");
580 case SSL_ERROR_SYSCALL:
581 /* SSL_ERROR_WANT_CONNECT, SSL_ERROR_WANT_ACCEPT,
582 * and SSL_ERROR_WANT_X509_LOOKUP */
583 sslerr = ERR_get_error();
585 Log(LOG_ERR, "SSL error: %s [in %s()]!",
586 ERR_error_string(sslerr, NULL), fname);
588 switch (code) { /* EOF that violated protocol */
591 "SSL error, client disconnected [in %s()]!",
594 case -1: /* low level socket I/O error, check errno */
595 Log(LOG_ERR, "SSL error: %s [in %s()]!",
596 strerror(real_errno), fname);
601 LogOpenSSLError("SSL protocol error", fname);
604 Log(LOG_ERR, "Unknown SSL error %d [in %s()]!", ret, fname);
609 #ifdef HAVE_LIBGNUTLS
612 case GNUTLS_E_INTERRUPTED:
613 if (gnutls_record_get_direction(c->ssl_state.gnutls_session)) {
614 Conn_OPTION_ADD(c, CONN_SSL_WANT_WRITE);
615 io_event_del(c->sock, IO_WANTREAD);
617 Conn_OPTION_ADD(c, CONN_SSL_WANT_READ);
618 io_event_del(c->sock, IO_WANTWRITE);
623 if (gnutls_error_is_fatal(code)) {
624 Log(LOG_ERR, "SSL error: %s [%s].",
625 gnutls_strerror(code), fname);
636 ConnSSL_LogCertInfo( CONNECTION *c )
639 SSL *ssl = c->ssl_state.ssl;
643 Log(LOG_INFO, "Connection %d: initialized %s using cipher %s.",
644 c->sock, SSL_get_version(ssl), SSL_get_cipher(ssl));
646 #ifdef HAVE_LIBGNUTLS
647 gnutls_session_t sess = c->ssl_state.gnutls_session;
648 gnutls_cipher_algorithm_t cipher = gnutls_cipher_get(sess);
650 Log(LOG_INFO, "Connection %d: initialized %s using cipher %s-%s.",
652 gnutls_protocol_get_name(gnutls_protocol_get_version(sess)),
653 gnutls_cipher_get_name(cipher),
654 gnutls_mac_get_name(gnutls_mac_get(sess)));
660 Accept incoming SSL connection.
662 1: SSL Connection established
664 -1: SSL Connection not established due to fatal error.
667 ConnSSL_Accept( CONNECTION *c )
670 if (!Conn_OPTION_ISSET(c, CONN_SSL)) {
671 #ifdef HAVE_LIBGNUTLS
672 int err = gnutls_init(&c->ssl_state.gnutls_session, GNUTLS_SERVER);
674 Log(LOG_ERR, "Failed to initialize new SSL session: %s",
675 gnutls_strerror(err));
679 if (!ConnSSL_Init_SSL(c))
682 return ConnectAccept(c, false );
687 ConnSSL_Connect( CONNECTION *c )
691 assert(c->ssl_state.ssl);
693 assert(Conn_OPTION_ISSET(c, CONN_SSL));
694 return ConnectAccept(c, true);
698 ConnSSL_InitCertFp( CONNECTION *c )
700 const char hex[] = "0123456789abcdef";
704 unsigned char digest[EVP_MAX_MD_SIZE];
705 unsigned int digest_size;
708 cert = SSL_get_peer_certificate(c->ssl_state.ssl);
712 if (!X509_digest(cert, EVP_sha256(), digest, &digest_size)) {
718 #endif /* HAVE_LIBSSL */
719 #ifdef HAVE_LIBGNUTLS
720 gnutls_x509_crt_t cert;
721 unsigned int cert_list_size;
722 const gnutls_datum_t *cert_list;
723 unsigned char digest[MAX_HASH_SIZE];
726 if (gnutls_certificate_type_get(c->ssl_state.gnutls_session) !=
730 if (gnutls_x509_crt_init(&cert) != GNUTLS_E_SUCCESS)
734 cert_list = gnutls_certificate_get_peers(c->ssl_state.gnutls_session,
737 gnutls_x509_crt_deinit(cert);
741 if (gnutls_x509_crt_import(cert, &cert_list[0],
742 GNUTLS_X509_FMT_DER) != GNUTLS_E_SUCCESS) {
743 gnutls_x509_crt_deinit(cert);
747 digest_size = sizeof(digest);
748 if (gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_SHA256, digest,
750 gnutls_x509_crt_deinit(cert);
754 gnutls_x509_crt_deinit(cert);
755 #endif /* HAVE_LIBGNUTLS */
757 assert(c->ssl_state.fingerprint == NULL);
759 c->ssl_state.fingerprint = malloc(SHA256_STRING_LEN);
760 if (!c->ssl_state.fingerprint)
763 for (i = 0; i < (int)digest_size; i++) {
764 c->ssl_state.fingerprint[i * 2] = hex[digest[i] / 16];
765 c->ssl_state.fingerprint[i * 2 + 1] = hex[digest[i] % 16];
767 c->ssl_state.fingerprint[i * 2] = '\0';
772 /* accept/connect wrapper. if connect is true, connect to peer, otherwise wait for incoming connection */
774 ConnectAccept( CONNECTION *c, bool connect)
778 SSL *ssl = c->ssl_state.ssl;
781 ret = connect ? SSL_connect(ssl) : SSL_accept(ssl);
783 return ConnSSL_HandleError(c, ret, connect ? "SSL_connect": "SSL_accept");
785 #ifdef HAVE_LIBGNUTLS
787 ret = gnutls_handshake(c->ssl_state.gnutls_session);
789 return ConnSSL_HandleError(c, ret, "gnutls_handshake");
791 (void)ConnSSL_InitCertFp(c);
793 Conn_OPTION_DEL(c, (CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ|CONN_SSL_CONNECT));
794 ConnSSL_LogCertInfo(c);
796 Conn_StartLogin(CONNECTION2ID(c));
802 ConnSSL_Write(CONNECTION *c, const void *buf, size_t count)
806 Conn_OPTION_DEL(c, CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ);
810 bw = (ssize_t) SSL_write(c->ssl_state.ssl, buf, count);
812 #ifdef HAVE_LIBGNUTLS
813 bw = gnutls_write(c->ssl_state.gnutls_session, buf, count);
817 if (ConnSSL_HandleError( c, bw, "ConnSSL_Write") == 0)
818 errno = EAGAIN; /* try again */
824 ConnSSL_Read(CONNECTION *c, void * buf, size_t count)
828 Conn_OPTION_DEL(c, CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ);
830 br = (ssize_t) SSL_read(c->ssl_state.ssl, buf, count);
831 if (br > 0) /* on EOF we have to call ConnSSL_HandleError(), see SSL_read(3) */
834 #ifdef HAVE_LIBGNUTLS
835 br = gnutls_read(c->ssl_state.gnutls_session, buf, count);
836 if (br >= 0) /* on EOF we must _not_ call ConnSSL_HandleError, see gnutls_record_recv(3) */
839 /* error on read: switch ConnSSL_HandleError() return values -> 0 is "try again", so return -1 and set EAGAIN */
840 if (ConnSSL_HandleError(c, br, "ConnSSL_Read") == 0) {
849 ConnSSL_GetCipherInfo(CONNECTION *c, char *buf, size_t len)
853 SSL *ssl = c->ssl_state.ssl;
858 SSL_CIPHER_description(SSL_get_current_cipher(ssl), buf, len);
859 nl = strchr(buf, '\n');
864 #ifdef HAVE_LIBGNUTLS
865 if (Conn_OPTION_ISSET(c, CONN_SSL)) {
866 const char *name_cipher, *name_mac, *name_proto, *name_keyexchange;
869 gnutls_session_t sess = c->ssl_state.gnutls_session;
870 gnutls_cipher_algorithm_t cipher = gnutls_cipher_get(sess);
871 name_cipher = gnutls_cipher_get_name(cipher);
872 name_mac = gnutls_mac_get_name(gnutls_mac_get(sess));
873 keysize = gnutls_cipher_get_key_size(cipher) * 8;
874 name_proto = gnutls_protocol_get_name(gnutls_protocol_get_version(sess));
875 name_keyexchange = gnutls_kx_get_name(gnutls_kx_get(sess));
877 return snprintf(buf, len, "%s-%s%15s Kx=%s Enc=%s(%u) Mac=%s",
878 name_cipher, name_mac, name_proto, name_keyexchange, name_cipher, keysize, name_mac) > 0;
885 ConnSSL_GetCertFp(CONNECTION *c)
887 return c->ssl_state.fingerprint;
891 ConnSSL_SetCertFp(CONNECTION *c, const char *fingerprint)
894 c->ssl_state.fingerprint = strndup(fingerprint, SHA256_STRING_LEN - 1);
895 return c->ssl_state.fingerprint != NULL;
900 ConnSSL_InitLibrary(void)
905 #endif /* SSL_SUPPORT */