2 * ngIRCd -- The Next Generation IRC Daemon
3 * Copyright (c) 2005-2008 Florian Westphal <fw@strlen.de>
10 * SSL wrapper functions
28 #include "conn-func.h"
35 extern struct SSLOptions Conf_SSLOptions;
38 #include <openssl/err.h>
39 #include <openssl/rand.h>
41 static SSL_CTX * ssl_ctx;
44 static bool ConnSSL_LoadServerKey_openssl PARAMS(( SSL_CTX *c ));
48 #include <sys/types.h>
52 #include <gnutls/x509.h>
55 #define DH_BITS_MIN 1024
57 #define MAX_HASH_SIZE 64 /* from gnutls-int.h */
59 static gnutls_certificate_credentials_t x509_cred;
60 static gnutls_dh_params_t dh_params;
61 static gnutls_priority_t priorities_cache;
62 static bool ConnSSL_LoadServerKey_gnutls PARAMS(( void ));
65 #define SHA256_STRING_LEN (32 * 2 + 1)
67 static bool ConnSSL_Init_SSL PARAMS(( CONNECTION *c ));
68 static int ConnectAccept PARAMS(( CONNECTION *c, bool connect ));
69 static int ConnSSL_HandleError PARAMS(( CONNECTION *c, const int code, const char *fname ));
72 static char * openreadclose(const char *name, size_t *len)
77 int fd = open(name, O_RDONLY);
79 Log(LOG_ERR, "Could not open %s: %s", name, strerror(errno));
83 Log(LOG_ERR, "Could not fstat %s: %s", name, strerror(errno));
86 if (!S_ISREG(s.st_mode)) {
87 Log(LOG_ERR, "%s: Not a regular file", name);
91 Log(LOG_ERR, "%s: invalid file length (size %ld <= 0)", name, (long) s.st_size);
94 buf = malloc(s.st_size);
96 Log(LOG_ERR, "Could not malloc %lu bytes for file %s: %s", s.st_size, name, strerror(errno));
99 br = read(fd, buf, s.st_size);
100 if (br != (ssize_t)s.st_size) {
101 Log(LOG_ERR, "Could not read file %s: read returned %ld, expected %ld: %s",
102 name, (long) br, (long) s.st_size, br == -1 ? strerror(errno):"short read?!");
103 memset(buf, 0, s.st_size);
118 * Log OpenSSL error message.
120 * @param msg The error message.
121 * @param info Additional information text or NULL.
124 LogOpenSSLError(const char *error, const char *info)
126 unsigned long err = ERR_get_error();
128 ? ERR_error_string(err, NULL)
129 : "Unable to determine error";
131 assert(error != NULL);
134 Log(LOG_ERR, "%s: %s (%s)", error, info, errmsg);
136 Log(LOG_ERR, "%s: %s", error, errmsg);
141 pem_passwd_cb(char *buf, int size, int rwflag, void *password)
143 array *pass = password;
146 (void)rwflag; /* rwflag is unused if DEBUG is not set. */
147 assert(rwflag == 0); /* 0 -> callback used for decryption.
148 * See SSL_CTX_set_default_passwd_cb(3) */
150 passlen = (int) array_bytes(pass);
152 LogDebug("pem_passwd_cb buf size %d, array size %d", size, passlen);
153 assert(passlen >= 0);
155 Log(LOG_ERR, "PEM password required but not set [in pem_passwd_cb()]!");
158 size = passlen > size ? size : passlen;
159 memcpy(buf, (char *)(array_start(pass)), size);
165 Verify_openssl(UNUSED int preverify_ok, UNUSED X509_STORE_CTX *x509_ctx)
179 if (!Conf_SSLOptions.DHFile) {
180 Log(LOG_NOTICE, "Configuration option \"DHFile\" not set!");
183 fp = fopen(Conf_SSLOptions.DHFile, "r");
185 Log(LOG_ERR, "%s: %s", Conf_SSLOptions.DHFile, strerror(errno));
188 dh_params = PEM_read_DHparams(fp, NULL, NULL, NULL);
190 Log(LOG_ERR, "%s: Failed to read SSL DH parameters!",
191 Conf_SSLOptions.DHFile);
197 #ifdef HAVE_LIBGNUTLS
198 bool need_dhgenerate = true;
200 gnutls_dh_params_t tmp_dh_params;
202 err = gnutls_dh_params_init(&tmp_dh_params);
204 Log(LOG_ERR, "Failed to initialize SSL DH parameters: %s",
205 gnutls_strerror(err));
208 if (Conf_SSLOptions.DHFile) {
209 gnutls_datum_t dhparms;
211 dhparms.data = (unsigned char *) openreadclose(Conf_SSLOptions.DHFile, &size);
214 err = gnutls_dh_params_import_pkcs3(tmp_dh_params, &dhparms, GNUTLS_X509_FMT_PEM);
216 need_dhgenerate = false;
219 "Failed to initialize SSL DH parameters: %s",
220 gnutls_strerror(err));
222 memset(dhparms.data, 0, size);
226 if (need_dhgenerate) {
228 "DHFile not set, generating %u bit DH parameters. This may take a while ...",
230 err = gnutls_dh_params_generate2(tmp_dh_params, DH_BITS);
232 Log(LOG_ERR, "Failed to generate SSL DH parameters: %s",
233 gnutls_strerror(err));
237 dh_params = tmp_dh_params;
243 void ConnSSL_Free(CONNECTION *c)
246 SSL *ssl = c->ssl_state.ssl;
250 c->ssl_state.ssl = NULL;
251 if (c->ssl_state.fingerprint) {
252 free(c->ssl_state.fingerprint);
253 c->ssl_state.fingerprint = NULL;
257 #ifdef HAVE_LIBGNUTLS
258 gnutls_session_t sess = c->ssl_state.gnutls_session;
259 if (Conn_OPTION_ISSET(c, CONN_SSL)) {
260 gnutls_bye(sess, GNUTLS_SHUT_RDWR);
264 assert(Conn_OPTION_ISSET(c, CONN_SSL));
265 /* can't just set bitmask to 0 -- there are other, non-ssl related flags, e.g. CONN_ZIP. */
266 Conn_OPTION_DEL(c, CONN_SSL_FLAGS_ALL);
271 ConnSSL_InitLibrary( void )
273 if (!Conf_SSLInUse()) {
274 LogDebug("SSL not in use, skipping initialization.");
283 SSL_load_error_strings();
286 if (!RAND_status()) {
287 Log(LOG_ERR, "OpenSSL PRNG not seeded: /dev/urandom missing?");
289 * it is probably best to fail and let the user install EGD or
290 * a similar program if no kernel random device is available.
291 * According to OpenSSL RAND_egd(3): "The automatic query of
292 * /var/run/egd-pool et al was added in OpenSSL 0.9.7";
293 * so it makes little sense to deal with PRNGD seeding ourselves.
295 array_free(&Conf_SSLOptions.ListenPorts);
299 newctx = SSL_CTX_new(SSLv23_method());
301 LogOpenSSLError("Failed to create SSL context", NULL);
302 array_free(&Conf_SSLOptions.ListenPorts);
306 if (!ConnSSL_LoadServerKey_openssl(newctx))
309 if (SSL_CTX_set_cipher_list(newctx, Conf_SSLOptions.CipherList) == 0) {
310 Log(LOG_ERR, "Failed to apply OpenSSL cipher list \"%s\"!",
311 Conf_SSLOptions.CipherList);
315 SSL_CTX_set_options(newctx, SSL_OP_SINGLE_DH_USE|SSL_OP_NO_SSLv2);
316 SSL_CTX_set_mode(newctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
317 SSL_CTX_set_verify(newctx, SSL_VERIFY_PEER|SSL_VERIFY_CLIENT_ONCE,
319 SSL_CTX_free(ssl_ctx);
321 Log(LOG_INFO, "%s initialized.", SSLeay_version(SSLEAY_VERSION));
324 SSL_CTX_free(newctx);
325 array_free(&Conf_SSLOptions.ListenPorts);
328 #ifdef HAVE_LIBGNUTLS
330 static bool initialized;
333 /* TODO: cannot reload gnutls keys: can't simply free x509
334 * context -- it may still be in use */
338 err = gnutls_global_init();
340 Log(LOG_ERR, "Failed to initialize GnuTLS: %s",
341 gnutls_strerror(err));
345 if (!ConnSSL_LoadServerKey_gnutls())
348 if (gnutls_priority_init(&priorities_cache, Conf_SSLOptions.CipherList,
349 NULL) != GNUTLS_E_SUCCESS) {
351 "Failed to apply GnuTLS cipher list \"%s\"!",
352 Conf_SSLOptions.CipherList);
356 Log(LOG_INFO, "GnuTLS %s initialized.", gnutls_check_version(NULL));
360 array_free(&Conf_SSLOptions.ListenPorts);
366 #ifdef HAVE_LIBGNUTLS
368 ConnSSL_LoadServerKey_gnutls(void)
371 const char *cert_file;
373 err = gnutls_certificate_allocate_credentials(&x509_cred);
375 Log(LOG_ERR, "Failed to allocate certificate credentials: %s",
376 gnutls_strerror(err));
380 cert_file = Conf_SSLOptions.CertFile ? Conf_SSLOptions.CertFile:Conf_SSLOptions.KeyFile;
382 Log(LOG_ERR, "No SSL server key configured!");
386 if (array_bytes(&Conf_SSLOptions.KeyFilePassword))
388 "Ignoring SSL \"KeyFilePassword\": Not supported by GnuTLS.");
390 if (!Load_DH_params())
393 gnutls_certificate_set_dh_params(x509_cred, dh_params);
394 err = gnutls_certificate_set_x509_key_file(x509_cred, cert_file, Conf_SSLOptions.KeyFile, GNUTLS_X509_FMT_PEM);
397 "Failed to set certificate key file (cert %s, key %s): %s",
399 Conf_SSLOptions.KeyFile ? Conf_SSLOptions.KeyFile : "(NULL)",
400 gnutls_strerror(err));
410 ConnSSL_LoadServerKey_openssl(SSL_CTX *ctx)
415 if (!Conf_SSLOptions.KeyFile) {
416 Log(LOG_ERR, "No SSL server key configured!");
420 SSL_CTX_set_default_passwd_cb(ctx, pem_passwd_cb);
421 SSL_CTX_set_default_passwd_cb_userdata(ctx, &Conf_SSLOptions.KeyFilePassword);
423 if (SSL_CTX_use_PrivateKey_file(ctx, Conf_SSLOptions.KeyFile, SSL_FILETYPE_PEM) != 1) {
424 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
425 LogOpenSSLError("Failed to add private key", Conf_SSLOptions.KeyFile);
429 cert_key = Conf_SSLOptions.CertFile ? Conf_SSLOptions.CertFile:Conf_SSLOptions.KeyFile;
430 if (SSL_CTX_use_certificate_chain_file(ctx, cert_key) != 1) {
431 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
432 LogOpenSSLError("Failed to load certificate chain", cert_key);
436 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
438 if (!SSL_CTX_check_private_key(ctx)) {
439 LogOpenSSLError("Server private key does not match certificate", NULL);
442 if (Load_DH_params()) {
443 if (SSL_CTX_set_tmp_dh(ctx, dh_params) != 1)
444 LogOpenSSLError("Error setting DH parameters", Conf_SSLOptions.DHFile);
445 /* don't return false here: the non-DH modes will still work */
455 ConnSSL_Init_SSL(CONNECTION *c)
459 LogDebug("Initializing SSL ...");
465 "Can't initialize SSL context, OpenSSL initialization failed at startup!");
468 assert(c->ssl_state.ssl == NULL);
469 assert(c->ssl_state.fingerprint == NULL);
471 c->ssl_state.ssl = SSL_new(ssl_ctx);
472 if (!c->ssl_state.ssl) {
473 LogOpenSSLError("Failed to create SSL structure", NULL);
476 Conn_OPTION_ADD(c, CONN_SSL);
478 ret = SSL_set_fd(c->ssl_state.ssl, c->sock);
480 LogOpenSSLError("Failed to set SSL file descriptor", NULL);
485 #ifdef HAVE_LIBGNUTLS
486 Conn_OPTION_ADD(c, CONN_SSL);
487 ret = gnutls_priority_set(c->ssl_state.gnutls_session, priorities_cache);
488 if (ret != GNUTLS_E_SUCCESS) {
489 Log(LOG_ERR, "Failed to set GnuTLS session priorities: %s",
490 gnutls_strerror(ret));
495 * The intermediate (long) cast is here to avoid a warning like:
496 * "cast to pointer from integer of different size" on 64-bit platforms.
497 * There doesn't seem to be an alternate GNUTLS API we could use instead, see e.g.
498 * http://www.mail-archive.com/help-gnutls@gnu.org/msg00286.html
500 gnutls_transport_set_ptr(c->ssl_state.gnutls_session,
501 (gnutls_transport_ptr_t) (long) c->sock);
502 gnutls_certificate_server_set_request(c->ssl_state.gnutls_session,
503 GNUTLS_CERT_REQUEST);
504 ret = gnutls_credentials_set(c->ssl_state.gnutls_session,
505 GNUTLS_CRD_CERTIFICATE, x509_cred);
507 Log(LOG_ERR, "Failed to set SSL credentials: %s",
508 gnutls_strerror(ret));
512 gnutls_dh_set_prime_bits(c->ssl_state.gnutls_session, DH_BITS_MIN);
519 ConnSSL_PrepareConnect(CONNECTION *c, UNUSED CONF_SERVER *s)
522 #ifdef HAVE_LIBGNUTLS
525 err = gnutls_init(&c->ssl_state.gnutls_session, GNUTLS_CLIENT);
527 Log(LOG_ERR, "Failed to initialize new SSL session: %s",
528 gnutls_strerror(err));
532 ret = ConnSSL_Init_SSL(c);
535 Conn_OPTION_ADD(c, CONN_SSL_CONNECT);
537 assert(c->ssl_state.ssl);
538 SSL_set_verify(c->ssl_state.ssl, SSL_VERIFY_NONE, NULL);
545 * Check and handle error return codes after failed calls to SSL functions.
548 * SSL_connect(), SSL_accept(), SSL_do_handshake(), SSL_read(), SSL_peek(), or
549 * SSL_write() on ssl.
552 * gnutlsssl_read(), gnutls_write() or gnutls_handshake().
554 * @param c The connection handle.
555 * @prarm code The return code.
556 * @param fname The name of the function in which the error occurred.
557 * @return -1 on fatal errors, 0 if we can try again later.
560 ConnSSL_HandleError(CONNECTION * c, const int code, const char *fname)
563 int ret = SSL_ERROR_SYSCALL;
564 unsigned long sslerr;
565 int real_errno = errno;
567 ret = SSL_get_error(c->ssl_state.ssl, code);
570 case SSL_ERROR_WANT_READ:
571 io_event_del(c->sock, IO_WANTWRITE);
572 Conn_OPTION_ADD(c, CONN_SSL_WANT_READ);
573 return 0; /* try again later */
574 case SSL_ERROR_WANT_WRITE:
575 io_event_del(c->sock, IO_WANTREAD);
576 Conn_OPTION_ADD(c, CONN_SSL_WANT_WRITE); /* fall through */
578 return 0; /* try again later */
579 case SSL_ERROR_ZERO_RETURN:
580 LogDebug("SSL connection shut down normally.");
582 case SSL_ERROR_SYSCALL:
583 /* SSL_ERROR_WANT_CONNECT, SSL_ERROR_WANT_ACCEPT,
584 * and SSL_ERROR_WANT_X509_LOOKUP */
585 sslerr = ERR_get_error();
587 Log(LOG_ERR, "SSL error: %s [in %s()]!",
588 ERR_error_string(sslerr, NULL), fname);
590 switch (code) { /* EOF that violated protocol */
593 "SSL error, client disconnected [in %s()]!",
596 case -1: /* low level socket I/O error, check errno */
597 Log(LOG_ERR, "SSL error: %s [in %s()]!",
598 strerror(real_errno), fname);
603 LogOpenSSLError("SSL protocol error", fname);
606 Log(LOG_ERR, "Unknown SSL error %d [in %s()]!", ret, fname);
611 #ifdef HAVE_LIBGNUTLS
614 case GNUTLS_E_INTERRUPTED:
615 if (gnutls_record_get_direction(c->ssl_state.gnutls_session)) {
616 Conn_OPTION_ADD(c, CONN_SSL_WANT_WRITE);
617 io_event_del(c->sock, IO_WANTREAD);
619 Conn_OPTION_ADD(c, CONN_SSL_WANT_READ);
620 io_event_del(c->sock, IO_WANTWRITE);
625 if (gnutls_error_is_fatal(code)) {
626 Log(LOG_ERR, "SSL error: %s [%s].",
627 gnutls_strerror(code), fname);
638 ConnSSL_LogCertInfo( CONNECTION *c )
641 SSL *ssl = c->ssl_state.ssl;
645 Log(LOG_INFO, "Connection %d: initialized %s using cipher %s.",
646 c->sock, SSL_get_version(ssl), SSL_get_cipher(ssl));
648 #ifdef HAVE_LIBGNUTLS
649 gnutls_session_t sess = c->ssl_state.gnutls_session;
650 gnutls_cipher_algorithm_t cipher = gnutls_cipher_get(sess);
652 Log(LOG_INFO, "Connection %d: initialized %s using cipher %s-%s.",
654 gnutls_protocol_get_name(gnutls_protocol_get_version(sess)),
655 gnutls_cipher_get_name(cipher),
656 gnutls_mac_get_name(gnutls_mac_get(sess)));
662 Accept incoming SSL connection.
664 1: SSL Connection established
666 -1: SSL Connection not established due to fatal error.
669 ConnSSL_Accept( CONNECTION *c )
672 if (!Conn_OPTION_ISSET(c, CONN_SSL)) {
673 #ifdef HAVE_LIBGNUTLS
674 int err = gnutls_init(&c->ssl_state.gnutls_session, GNUTLS_SERVER);
676 Log(LOG_ERR, "Failed to initialize new SSL session: %s",
677 gnutls_strerror(err));
681 if (!ConnSSL_Init_SSL(c))
684 return ConnectAccept(c, false );
689 ConnSSL_Connect( CONNECTION *c )
693 assert(c->ssl_state.ssl);
695 assert(Conn_OPTION_ISSET(c, CONN_SSL));
696 return ConnectAccept(c, true);
700 ConnSSL_InitCertFp( CONNECTION *c )
702 const char hex[] = "0123456789abcdef";
706 unsigned char digest[EVP_MAX_MD_SIZE];
707 unsigned int digest_size;
710 cert = SSL_get_peer_certificate(c->ssl_state.ssl);
714 if (!X509_digest(cert, EVP_sha256(), digest, &digest_size)) {
720 #endif /* HAVE_LIBSSL */
721 #ifdef HAVE_LIBGNUTLS
722 gnutls_x509_crt_t cert;
723 unsigned int cert_list_size;
724 const gnutls_datum_t *cert_list;
725 unsigned char digest[MAX_HASH_SIZE];
728 if (gnutls_certificate_type_get(c->ssl_state.gnutls_session) !=
732 if (gnutls_x509_crt_init(&cert) != GNUTLS_E_SUCCESS)
736 cert_list = gnutls_certificate_get_peers(c->ssl_state.gnutls_session,
739 gnutls_x509_crt_deinit(cert);
743 if (gnutls_x509_crt_import(cert, &cert_list[0],
744 GNUTLS_X509_FMT_DER) != GNUTLS_E_SUCCESS) {
745 gnutls_x509_crt_deinit(cert);
749 digest_size = sizeof(digest);
750 if (gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_SHA256, digest,
752 gnutls_x509_crt_deinit(cert);
756 gnutls_x509_crt_deinit(cert);
757 #endif /* HAVE_LIBGNUTLS */
759 assert(c->ssl_state.fingerprint == NULL);
761 c->ssl_state.fingerprint = malloc(SHA256_STRING_LEN);
762 if (!c->ssl_state.fingerprint)
765 for (i = 0; i < (int)digest_size; i++) {
766 c->ssl_state.fingerprint[i * 2] = hex[digest[i] / 16];
767 c->ssl_state.fingerprint[i * 2 + 1] = hex[digest[i] % 16];
769 c->ssl_state.fingerprint[i * 2] = '\0';
774 /* accept/connect wrapper. if connect is true, connect to peer, otherwise wait for incoming connection */
776 ConnectAccept( CONNECTION *c, bool connect)
780 SSL *ssl = c->ssl_state.ssl;
783 ret = connect ? SSL_connect(ssl) : SSL_accept(ssl);
785 return ConnSSL_HandleError(c, ret, connect ? "SSL_connect": "SSL_accept");
787 #ifdef HAVE_LIBGNUTLS
789 ret = gnutls_handshake(c->ssl_state.gnutls_session);
791 return ConnSSL_HandleError(c, ret, "gnutls_handshake");
793 (void)ConnSSL_InitCertFp(c);
795 Conn_OPTION_DEL(c, (CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ|CONN_SSL_CONNECT));
796 ConnSSL_LogCertInfo(c);
798 Conn_StartLogin(CONNECTION2ID(c));
804 ConnSSL_Write(CONNECTION *c, const void *buf, size_t count)
808 Conn_OPTION_DEL(c, CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ);
812 bw = (ssize_t) SSL_write(c->ssl_state.ssl, buf, count);
814 #ifdef HAVE_LIBGNUTLS
815 bw = gnutls_write(c->ssl_state.gnutls_session, buf, count);
819 if (ConnSSL_HandleError( c, bw, "ConnSSL_Write") == 0)
820 errno = EAGAIN; /* try again */
826 ConnSSL_Read(CONNECTION *c, void * buf, size_t count)
830 Conn_OPTION_DEL(c, CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ);
832 br = (ssize_t) SSL_read(c->ssl_state.ssl, buf, count);
833 if (br > 0) /* on EOF we have to call ConnSSL_HandleError(), see SSL_read(3) */
836 #ifdef HAVE_LIBGNUTLS
837 br = gnutls_read(c->ssl_state.gnutls_session, buf, count);
838 if (br >= 0) /* on EOF we must _not_ call ConnSSL_HandleError, see gnutls_record_recv(3) */
841 /* error on read: switch ConnSSL_HandleError() return values -> 0 is "try again", so return -1 and set EAGAIN */
842 if (ConnSSL_HandleError(c, br, "ConnSSL_Read") == 0) {
851 ConnSSL_GetCipherInfo(CONNECTION *c, char *buf, size_t len)
855 SSL *ssl = c->ssl_state.ssl;
860 SSL_CIPHER_description(SSL_get_current_cipher(ssl), buf, len);
861 nl = strchr(buf, '\n');
866 #ifdef HAVE_LIBGNUTLS
867 if (Conn_OPTION_ISSET(c, CONN_SSL)) {
868 const char *name_cipher, *name_mac, *name_proto, *name_keyexchange;
871 gnutls_session_t sess = c->ssl_state.gnutls_session;
872 gnutls_cipher_algorithm_t cipher = gnutls_cipher_get(sess);
873 name_cipher = gnutls_cipher_get_name(cipher);
874 name_mac = gnutls_mac_get_name(gnutls_mac_get(sess));
875 keysize = gnutls_cipher_get_key_size(cipher) * 8;
876 name_proto = gnutls_protocol_get_name(gnutls_protocol_get_version(sess));
877 name_keyexchange = gnutls_kx_get_name(gnutls_kx_get(sess));
879 return snprintf(buf, len, "%s-%s%15s Kx=%s Enc=%s(%u) Mac=%s",
880 name_cipher, name_mac, name_proto, name_keyexchange, name_cipher, keysize, name_mac) > 0;
887 ConnSSL_GetCertFp(CONNECTION *c)
889 return c->ssl_state.fingerprint;
893 ConnSSL_SetCertFp(CONNECTION *c, const char *fingerprint)
896 c->ssl_state.fingerprint = strndup(fingerprint, SHA256_STRING_LEN - 1);
897 return c->ssl_state.fingerprint != NULL;
902 ConnSSL_InitLibrary(void)
907 #endif /* SSL_SUPPORT */