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 bool ConnSSL_LoadServerKey_gnutls PARAMS(( void ));
64 #define SHA1_STRING_LEN (20 * 2 + 1)
66 static bool ConnSSL_Init_SSL PARAMS(( CONNECTION *c ));
67 static int ConnectAccept PARAMS(( CONNECTION *c, bool connect ));
68 static int ConnSSL_HandleError PARAMS(( CONNECTION *c, const int code, const char *fname ));
71 static char * openreadclose(const char *name, size_t *len)
76 int fd = open(name, O_RDONLY);
78 Log(LOG_ERR, "Could not open %s: %s", name, strerror(errno));
82 Log(LOG_ERR, "Could not fstat %s: %s", name, strerror(errno));
85 if (!S_ISREG(s.st_mode)) {
86 Log(LOG_ERR, "%s: Not a regular file", name);
90 Log(LOG_ERR, "%s: invalid file length (size %ld <= 0)", name, (long) s.st_size);
93 buf = malloc(s.st_size);
95 Log(LOG_ERR, "Could not malloc %lu bytes for file %s: %s", s.st_size, name, strerror(errno));
98 br = read(fd, buf, s.st_size);
99 if (br != (ssize_t)s.st_size) {
100 Log(LOG_ERR, "Could not read file %s: read returned %ld, expected %ld: %s",
101 name, (long) br, (long) s.st_size, br == -1 ? strerror(errno):"short read?!");
102 memset(buf, 0, s.st_size);
117 * Log OpenSSL error message.
119 * @param msg The error message.
120 * @param info Additional information text or NULL.
123 LogOpenSSLError(const char *error, const char *info)
125 unsigned long err = ERR_get_error();
127 ? ERR_error_string(err, NULL)
128 : "Unable to determine error";
130 assert(error != NULL);
133 Log(LOG_ERR, "%s: %s (%s)", error, info, errmsg);
135 Log(LOG_ERR, "%s: %s", error, errmsg);
140 pem_passwd_cb(char *buf, int size, int rwflag, void *password)
142 array *pass = password;
145 (void)rwflag; /* rwflag is unused if DEBUG is not set. */
146 assert(rwflag == 0); /* 0 -> callback used for decryption.
147 * See SSL_CTX_set_default_passwd_cb(3) */
149 passlen = (int) array_bytes(pass);
151 LogDebug("pem_passwd_cb buf size %d, array size %d", size, passlen);
152 assert(passlen >= 0);
154 Log(LOG_ERR, "PEM password required but not set [in pem_passwd_cb()]!");
157 size = passlen > size ? size : passlen;
158 memcpy(buf, (char *)(array_start(pass)), size);
164 Verify_openssl(UNUSED int preverify_ok, UNUSED X509_STORE_CTX *x509_ctx)
178 if (!Conf_SSLOptions.DHFile) {
179 Log(LOG_NOTICE, "Configuration option \"DHFile\" not set!");
182 fp = fopen(Conf_SSLOptions.DHFile, "r");
184 Log(LOG_ERR, "%s: %s", Conf_SSLOptions.DHFile, strerror(errno));
187 dh_params = PEM_read_DHparams(fp, NULL, NULL, NULL);
189 Log(LOG_ERR, "%s: Failed to read SSL DH parameters!",
190 Conf_SSLOptions.DHFile);
196 #ifdef HAVE_LIBGNUTLS
197 bool need_dhgenerate = true;
199 gnutls_dh_params_t tmp_dh_params;
201 err = gnutls_dh_params_init(&tmp_dh_params);
203 Log(LOG_ERR, "Failed to initialize SSL DH parameters: %s",
204 gnutls_strerror(err));
207 if (Conf_SSLOptions.DHFile) {
208 gnutls_datum_t dhparms;
210 dhparms.data = (unsigned char *) openreadclose(Conf_SSLOptions.DHFile, &size);
213 err = gnutls_dh_params_import_pkcs3(tmp_dh_params, &dhparms, GNUTLS_X509_FMT_PEM);
215 need_dhgenerate = false;
218 "Failed to initialize SSL DH parameters: %s",
219 gnutls_strerror(err));
221 memset(dhparms.data, 0, size);
225 if (need_dhgenerate) {
227 "DHFile not set, generating %u bit DH parameters. This may take a while ...",
229 err = gnutls_dh_params_generate2(tmp_dh_params, DH_BITS);
231 Log(LOG_ERR, "Failed to generate SSL DH parameters: %s",
232 gnutls_strerror(err));
236 dh_params = tmp_dh_params;
242 void ConnSSL_Free(CONNECTION *c)
245 SSL *ssl = c->ssl_state.ssl;
249 c->ssl_state.ssl = NULL;
250 if (c->ssl_state.fingerprint) {
251 free(c->ssl_state.fingerprint);
252 c->ssl_state.fingerprint = NULL;
256 #ifdef HAVE_LIBGNUTLS
257 gnutls_session_t sess = c->ssl_state.gnutls_session;
258 if (Conn_OPTION_ISSET(c, CONN_SSL)) {
259 gnutls_bye(sess, GNUTLS_SHUT_RDWR);
263 assert(Conn_OPTION_ISSET(c, CONN_SSL));
264 /* can't just set bitmask to 0 -- there are other, non-ssl related flags, e.g. CONN_ZIP. */
265 Conn_OPTION_DEL(c, CONN_SSL_FLAGS_ALL);
270 ConnSSL_InitLibrary( void )
272 if (!Conf_SSLInUse()) {
273 LogDebug("SSL not in use, skipping initialization.");
282 SSL_load_error_strings();
285 if (!RAND_status()) {
286 Log(LOG_ERR, "OpenSSL PRNG not seeded: /dev/urandom missing?");
288 * it is probably best to fail and let the user install EGD or
289 * a similar program if no kernel random device is available.
290 * According to OpenSSL RAND_egd(3): "The automatic query of
291 * /var/run/egd-pool et al was added in OpenSSL 0.9.7";
292 * so it makes little sense to deal with PRNGD seeding ourselves.
294 array_free(&Conf_SSLOptions.ListenPorts);
298 newctx = SSL_CTX_new(SSLv23_method());
300 LogOpenSSLError("Failed to create SSL context", NULL);
301 array_free(&Conf_SSLOptions.ListenPorts);
305 if (!ConnSSL_LoadServerKey_openssl(newctx))
308 SSL_CTX_set_options(newctx, SSL_OP_SINGLE_DH_USE|SSL_OP_NO_SSLv2);
309 SSL_CTX_set_mode(newctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
310 SSL_CTX_set_verify(newctx, SSL_VERIFY_PEER|SSL_VERIFY_CLIENT_ONCE,
312 SSL_CTX_free(ssl_ctx);
314 Log(LOG_INFO, "%s initialized.", SSLeay_version(SSLEAY_VERSION));
317 SSL_CTX_free(newctx);
318 array_free(&Conf_SSLOptions.ListenPorts);
321 #ifdef HAVE_LIBGNUTLS
323 static bool initialized;
326 /* TODO: cannot reload gnutls keys: can't simply free x509
327 * context -- it may still be in use */
331 err = gnutls_global_init();
333 Log(LOG_ERR, "Failed to initialize GnuTLS: %s",
334 gnutls_strerror(err));
335 array_free(&Conf_SSLOptions.ListenPorts);
338 if (!ConnSSL_LoadServerKey_gnutls()) {
339 array_free(&Conf_SSLOptions.ListenPorts);
342 Log(LOG_INFO, "GnuTLS %s initialized.", gnutls_check_version(NULL));
349 #ifdef HAVE_LIBGNUTLS
351 ConnSSL_LoadServerKey_gnutls(void)
354 const char *cert_file;
356 err = gnutls_certificate_allocate_credentials(&x509_cred);
358 Log(LOG_ERR, "Failed to allocate certificate credentials: %s",
359 gnutls_strerror(err));
363 cert_file = Conf_SSLOptions.CertFile ? Conf_SSLOptions.CertFile:Conf_SSLOptions.KeyFile;
365 Log(LOG_ERR, "No SSL server key configured!");
369 if (array_bytes(&Conf_SSLOptions.KeyFilePassword))
371 "Ignoring KeyFilePassword: Not supported by GnuTLS.");
373 if (!Load_DH_params())
376 gnutls_certificate_set_dh_params(x509_cred, dh_params);
377 err = gnutls_certificate_set_x509_key_file(x509_cred, cert_file, Conf_SSLOptions.KeyFile, GNUTLS_X509_FMT_PEM);
380 "Failed to set certificate key file (cert %s, key %s): %s",
382 Conf_SSLOptions.KeyFile ? Conf_SSLOptions.KeyFile : "(NULL)",
383 gnutls_strerror(err));
393 ConnSSL_LoadServerKey_openssl(SSL_CTX *ctx)
398 if (!Conf_SSLOptions.KeyFile) {
399 Log(LOG_ERR, "No SSL server key configured!");
403 SSL_CTX_set_default_passwd_cb(ctx, pem_passwd_cb);
404 SSL_CTX_set_default_passwd_cb_userdata(ctx, &Conf_SSLOptions.KeyFilePassword);
406 if (SSL_CTX_use_PrivateKey_file(ctx, Conf_SSLOptions.KeyFile, SSL_FILETYPE_PEM) != 1) {
407 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
408 LogOpenSSLError("Failed to add private key", Conf_SSLOptions.KeyFile);
412 cert_key = Conf_SSLOptions.CertFile ? Conf_SSLOptions.CertFile:Conf_SSLOptions.KeyFile;
413 if (SSL_CTX_use_certificate_chain_file(ctx, cert_key) != 1) {
414 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
415 LogOpenSSLError("Failed to load certificate chain", cert_key);
419 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
421 if (!SSL_CTX_check_private_key(ctx)) {
422 LogOpenSSLError("Server private key does not match certificate", NULL);
425 if (Load_DH_params()) {
426 if (SSL_CTX_set_tmp_dh(ctx, dh_params) != 1)
427 LogOpenSSLError("Error setting DH parameters", Conf_SSLOptions.DHFile);
428 /* don't return false here: the non-DH modes will still work */
438 ConnSSL_Init_SSL(CONNECTION *c)
445 "Can't initialize SSL context, OpenSSL initialization failed at startup!");
448 assert(c->ssl_state.ssl == NULL);
449 assert(c->ssl_state.fingerprint == NULL);
451 c->ssl_state.ssl = SSL_new(ssl_ctx);
452 if (!c->ssl_state.ssl) {
453 LogOpenSSLError("Failed to create SSL structure", NULL);
457 ret = SSL_set_fd(c->ssl_state.ssl, c->sock);
459 LogOpenSSLError("Failed to set SSL file descriptor", NULL);
464 #ifdef HAVE_LIBGNUTLS
465 ret = gnutls_set_default_priority(c->ssl_state.gnutls_session);
467 Log(LOG_ERR, "Failed to set GnuTLS default priority: %s",
468 gnutls_strerror(ret));
473 * The intermediate (long) cast is here to avoid a warning like:
474 * "cast to pointer from integer of different size" on 64-bit platforms.
475 * There doesn't seem to be an alternate GNUTLS API we could use instead, see e.g.
476 * http://www.mail-archive.com/help-gnutls@gnu.org/msg00286.html
478 gnutls_transport_set_ptr(c->ssl_state.gnutls_session, (gnutls_transport_ptr_t) (long) c->sock);
479 gnutls_certificate_server_set_request(c->ssl_state.gnutls_session, GNUTLS_CERT_REQUEST);
480 ret = gnutls_credentials_set(c->ssl_state.gnutls_session, GNUTLS_CRD_CERTIFICATE, x509_cred);
482 Log(LOG_ERR, "Failed to set SSL credentials: %s", gnutls_strerror(ret));
486 gnutls_dh_set_prime_bits(c->ssl_state.gnutls_session, DH_BITS_MIN);
488 Conn_OPTION_ADD(c, CONN_SSL);
494 ConnSSL_PrepareConnect(CONNECTION *c, UNUSED CONF_SERVER *s)
497 #ifdef HAVE_LIBGNUTLS
500 err = gnutls_init(&c->ssl_state.gnutls_session, GNUTLS_CLIENT);
502 Log(LOG_ERR, "Failed to initialize new SSL session: %s",
503 gnutls_strerror(err));
507 ret = ConnSSL_Init_SSL(c);
510 Conn_OPTION_ADD(c, CONN_SSL_CONNECT);
512 assert(c->ssl_state.ssl);
513 SSL_set_verify(c->ssl_state.ssl, SSL_VERIFY_NONE, NULL);
520 * Check and handle error return codes after failed calls to SSL functions.
523 * SSL_connect(), SSL_accept(), SSL_do_handshake(), SSL_read(), SSL_peek(), or
524 * SSL_write() on ssl.
527 * gnutlsssl_read(), gnutls_write() or gnutls_handshake().
529 * @param c The connection handle.
530 * @prarm code The return code.
531 * @param fname The name of the function in which the error occurred.
532 * @return -1 on fatal errors, 0 if we can try again later.
535 ConnSSL_HandleError(CONNECTION * c, const int code, const char *fname)
538 int ret = SSL_ERROR_SYSCALL;
539 unsigned long sslerr;
540 int real_errno = errno;
542 ret = SSL_get_error(c->ssl_state.ssl, code);
545 case SSL_ERROR_WANT_READ:
546 io_event_del(c->sock, IO_WANTWRITE);
547 Conn_OPTION_ADD(c, CONN_SSL_WANT_READ);
548 return 0; /* try again later */
549 case SSL_ERROR_WANT_WRITE:
550 io_event_del(c->sock, IO_WANTREAD);
551 Conn_OPTION_ADD(c, CONN_SSL_WANT_WRITE); /* fall through */
553 return 0; /* try again later */
554 case SSL_ERROR_ZERO_RETURN:
555 LogDebug("SSL connection shut down normally.");
557 case SSL_ERROR_SYSCALL:
558 /* SSL_ERROR_WANT_CONNECT, SSL_ERROR_WANT_ACCEPT,
559 * and SSL_ERROR_WANT_X509_LOOKUP */
560 sslerr = ERR_get_error();
562 Log(LOG_ERR, "SSL error: %s [in %s()]!",
563 ERR_error_string(sslerr, NULL), fname);
565 switch (code) { /* EOF that violated protocol */
568 "SSL error, client disconnected [in %s()]!",
571 case -1: /* low level socket I/O error, check errno */
572 Log(LOG_ERR, "SSL error: %s [in %s()]!",
573 strerror(real_errno), fname);
578 LogOpenSSLError("SSL protocol error", fname);
581 Log(LOG_ERR, "Unknown SSL error %d [in %s()]!", ret, fname);
586 #ifdef HAVE_LIBGNUTLS
589 case GNUTLS_E_INTERRUPTED:
590 if (gnutls_record_get_direction(c->ssl_state.gnutls_session)) {
591 Conn_OPTION_ADD(c, CONN_SSL_WANT_WRITE);
592 io_event_del(c->sock, IO_WANTREAD);
594 Conn_OPTION_ADD(c, CONN_SSL_WANT_READ);
595 io_event_del(c->sock, IO_WANTWRITE);
600 if (gnutls_error_is_fatal(code)) {
601 Log(LOG_ERR, "SSL error: %s [%s].",
602 gnutls_strerror(code), fname);
613 ConnSSL_LogCertInfo( CONNECTION *c )
616 SSL *ssl = c->ssl_state.ssl;
620 Log(LOG_INFO, "Connection %d: initialized %s using cipher %s.",
621 c->sock, SSL_get_version(ssl), SSL_get_cipher(ssl));
623 #ifdef HAVE_LIBGNUTLS
624 gnutls_session_t sess = c->ssl_state.gnutls_session;
625 gnutls_cipher_algorithm_t cipher = gnutls_cipher_get(sess);
627 Log(LOG_INFO, "Connection %d: initialized %s using cipher %s-%s.",
629 gnutls_protocol_get_name(gnutls_protocol_get_version(sess)),
630 gnutls_cipher_get_name(cipher),
631 gnutls_mac_get_name(gnutls_mac_get(sess)));
637 Accept incoming SSL connection.
639 1: SSL Connection established
641 -1: SSL Connection not established due to fatal error.
644 ConnSSL_Accept( CONNECTION *c )
647 if (!Conn_OPTION_ISSET(c, CONN_SSL)) {
648 #ifdef HAVE_LIBGNUTLS
649 int err = gnutls_init(&c->ssl_state.gnutls_session, GNUTLS_SERVER);
651 Log(LOG_ERR, "Failed to initialize new SSL session: %s",
652 gnutls_strerror(err));
656 LogDebug("Initializing SSL data ...");
657 if (!ConnSSL_Init_SSL(c))
660 return ConnectAccept(c, false );
665 ConnSSL_Connect( CONNECTION *c )
669 assert(c->ssl_state.ssl);
671 assert(Conn_OPTION_ISSET(c, CONN_SSL));
672 return ConnectAccept(c, true);
676 ConnSSL_InitCertFp( CONNECTION *c )
678 const char hex[] = "0123456789abcdef";
682 unsigned char digest[EVP_MAX_MD_SIZE];
683 unsigned int digest_size;
686 cert = SSL_get_peer_certificate(c->ssl_state.ssl);
690 if (!X509_digest(cert, EVP_sha1(), digest, &digest_size)) {
696 #endif /* HAVE_LIBSSL */
697 #ifdef HAVE_LIBGNUTLS
698 gnutls_x509_crt_t cert;
699 unsigned int cert_list_size;
700 const gnutls_datum_t *cert_list;
701 unsigned char digest[MAX_HASH_SIZE];
704 if (gnutls_certificate_type_get(c->ssl_state.gnutls_session) != GNUTLS_CRT_X509)
707 if (gnutls_x509_crt_init(&cert) != GNUTLS_E_SUCCESS)
711 cert_list = gnutls_certificate_get_peers(c->ssl_state.gnutls_session,
714 gnutls_x509_crt_deinit(cert);
718 if (gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER) != GNUTLS_E_SUCCESS) {
719 gnutls_x509_crt_deinit(cert);
723 digest_size = sizeof(digest);
724 if (gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_SHA1, digest, &digest_size)) {
725 gnutls_x509_crt_deinit(cert);
729 gnutls_x509_crt_deinit(cert);
730 #endif /* HAVE_LIBGNUTLS */
732 assert(c->ssl_state.fingerprint == NULL);
734 c->ssl_state.fingerprint = malloc(SHA1_STRING_LEN);
735 if (!c->ssl_state.fingerprint)
738 for (i = 0; i < (int)digest_size; i++) {
739 c->ssl_state.fingerprint[i * 2] = hex[digest[i] / 16];
740 c->ssl_state.fingerprint[i * 2 + 1] = hex[digest[i] % 16];
742 c->ssl_state.fingerprint[i * 2] = '\0';
747 /* accept/connect wrapper. if connect is true, connect to peer, otherwise wait for incoming connection */
749 ConnectAccept( CONNECTION *c, bool connect)
753 SSL *ssl = c->ssl_state.ssl;
756 ret = connect ? SSL_connect(ssl) : SSL_accept(ssl);
758 return ConnSSL_HandleError(c, ret, connect ? "SSL_connect": "SSL_accept");
760 #ifdef HAVE_LIBGNUTLS
762 ret = gnutls_handshake(c->ssl_state.gnutls_session);
764 return ConnSSL_HandleError(c, ret, "gnutls_handshake");
766 (void)ConnSSL_InitCertFp(c);
768 Conn_OPTION_DEL(c, (CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ|CONN_SSL_CONNECT));
769 ConnSSL_LogCertInfo(c);
771 Conn_StartLogin(CONNECTION2ID(c));
777 ConnSSL_Write(CONNECTION *c, const void *buf, size_t count)
781 Conn_OPTION_DEL(c, CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ);
785 bw = (ssize_t) SSL_write(c->ssl_state.ssl, buf, count);
787 #ifdef HAVE_LIBGNUTLS
788 bw = gnutls_write(c->ssl_state.gnutls_session, buf, count);
792 if (ConnSSL_HandleError( c, bw, "ConnSSL_Write") == 0)
793 errno = EAGAIN; /* try again */
799 ConnSSL_Read(CONNECTION *c, void * buf, size_t count)
803 Conn_OPTION_DEL(c, CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ);
805 br = (ssize_t) SSL_read(c->ssl_state.ssl, buf, count);
806 if (br > 0) /* on EOF we have to call ConnSSL_HandleError(), see SSL_read(3) */
809 #ifdef HAVE_LIBGNUTLS
810 br = gnutls_read(c->ssl_state.gnutls_session, buf, count);
811 if (br >= 0) /* on EOF we must _not_ call ConnSSL_HandleError, see gnutls_record_recv(3) */
814 /* error on read: switch ConnSSL_HandleError() return values -> 0 is "try again", so return -1 and set EAGAIN */
815 if (ConnSSL_HandleError(c, br, "ConnSSL_Read") == 0) {
824 ConnSSL_GetCipherInfo(CONNECTION *c, char *buf, size_t len)
828 SSL *ssl = c->ssl_state.ssl;
833 SSL_CIPHER_description(SSL_get_current_cipher(ssl), buf, len);
834 nl = strchr(buf, '\n');
839 #ifdef HAVE_LIBGNUTLS
840 if (Conn_OPTION_ISSET(c, CONN_SSL)) {
841 const char *name_cipher, *name_mac, *name_proto, *name_keyexchange;
844 gnutls_session_t sess = c->ssl_state.gnutls_session;
845 gnutls_cipher_algorithm_t cipher = gnutls_cipher_get(sess);
846 name_cipher = gnutls_cipher_get_name(cipher);
847 name_mac = gnutls_mac_get_name(gnutls_mac_get(sess));
848 keysize = gnutls_cipher_get_key_size(cipher) * 8;
849 name_proto = gnutls_protocol_get_name(gnutls_protocol_get_version(sess));
850 name_keyexchange = gnutls_kx_get_name(gnutls_kx_get(sess));
852 return snprintf(buf, len, "%s-%s%15s Kx=%s Enc=%s(%u) Mac=%s",
853 name_cipher, name_mac, name_proto, name_keyexchange, name_cipher, keysize, name_mac) > 0;
860 ConnSSL_GetCertFp(CONNECTION *c)
862 return c->ssl_state.fingerprint;
866 ConnSSL_SetCertFp(CONNECTION *c, const char *fingerprint)
869 c->ssl_state.fingerprint = strndup(fingerprint, SHA1_STRING_LEN - 1);
870 return c->ssl_state.fingerprint != NULL;
875 ConnSSL_InitLibrary(void)
880 #endif /* SSL_SUPPORT */