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 CERTFP_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 a similar program if no kernel random device is available.
289 * According to OpenSSL RAND_egd(3): "The automatic query of /var/run/egd-pool et al was added in OpenSSL 0.9.7";
290 * so it makes little sense to deal with PRNGD seeding ourselves.
292 array_free(&Conf_SSLOptions.ListenPorts);
296 newctx = SSL_CTX_new(SSLv23_method());
298 LogOpenSSLError("Failed to create SSL context", NULL);
299 array_free(&Conf_SSLOptions.ListenPorts);
303 if (!ConnSSL_LoadServerKey_openssl(newctx))
306 SSL_CTX_set_options(newctx, SSL_OP_SINGLE_DH_USE|SSL_OP_NO_SSLv2);
307 SSL_CTX_set_mode(newctx, SSL_MODE_ENABLE_PARTIAL_WRITE);
308 SSL_CTX_set_verify(newctx, SSL_VERIFY_PEER|SSL_VERIFY_CLIENT_ONCE, Verify_openssl);
309 SSL_CTX_free(ssl_ctx);
311 Log(LOG_INFO, "%s initialized.", SSLeay_version(SSLEAY_VERSION));
314 SSL_CTX_free(newctx);
315 array_free(&Conf_SSLOptions.ListenPorts);
318 #ifdef HAVE_LIBGNUTLS
320 static bool initialized;
321 if (initialized) /* TODO: cannot reload gnutls keys: can't simply free x509 context -- it may still be in use */
324 err = gnutls_global_init();
326 Log(LOG_ERR, "Failed to initialize GnuTLS: %s", gnutls_strerror(err));
327 array_free(&Conf_SSLOptions.ListenPorts);
330 if (!ConnSSL_LoadServerKey_gnutls()) {
331 array_free(&Conf_SSLOptions.ListenPorts);
334 Log(LOG_INFO, "GnuTLS %s initialized.", gnutls_check_version(NULL));
341 #ifdef HAVE_LIBGNUTLS
343 ConnSSL_LoadServerKey_gnutls(void)
346 const char *cert_file;
348 err = gnutls_certificate_allocate_credentials(&x509_cred);
350 Log(LOG_ERR, "Failed to allocate certificate credentials: %s",
351 gnutls_strerror(err));
355 cert_file = Conf_SSLOptions.CertFile ? Conf_SSLOptions.CertFile:Conf_SSLOptions.KeyFile;
357 Log(LOG_ERR, "No SSL server key configured!");
361 if (array_bytes(&Conf_SSLOptions.KeyFilePassword))
363 "Ignoring KeyFilePassword: Not supported by GnuTLS.");
365 if (!Load_DH_params())
368 gnutls_certificate_set_dh_params(x509_cred, dh_params);
369 err = gnutls_certificate_set_x509_key_file(x509_cred, cert_file, Conf_SSLOptions.KeyFile, GNUTLS_X509_FMT_PEM);
372 "Failed to set certificate key file (cert %s, key %s): %s",
374 Conf_SSLOptions.KeyFile ? Conf_SSLOptions.KeyFile : "(NULL)",
375 gnutls_strerror(err));
385 ConnSSL_LoadServerKey_openssl(SSL_CTX *ctx)
390 if (!Conf_SSLOptions.KeyFile) {
391 Log(LOG_ERR, "No SSL server key configured!");
395 SSL_CTX_set_default_passwd_cb(ctx, pem_passwd_cb);
396 SSL_CTX_set_default_passwd_cb_userdata(ctx, &Conf_SSLOptions.KeyFilePassword);
398 if (SSL_CTX_use_PrivateKey_file(ctx, Conf_SSLOptions.KeyFile, SSL_FILETYPE_PEM) != 1) {
399 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
400 LogOpenSSLError("Failed to add private key", Conf_SSLOptions.KeyFile);
404 cert_key = Conf_SSLOptions.CertFile ? Conf_SSLOptions.CertFile:Conf_SSLOptions.KeyFile;
405 if (SSL_CTX_use_certificate_chain_file(ctx, cert_key) != 1) {
406 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
407 LogOpenSSLError("Failed to load certificate chain", cert_key);
411 array_free_wipe(&Conf_SSLOptions.KeyFilePassword);
413 if (!SSL_CTX_check_private_key(ctx)) {
414 LogOpenSSLError("Server private key does not match certificate", NULL);
417 if (Load_DH_params()) {
418 if (SSL_CTX_set_tmp_dh(ctx, dh_params) != 1)
419 LogOpenSSLError("Error setting DH parameters", Conf_SSLOptions.DHFile);
420 /* don't return false here: the non-DH modes will still work */
430 ConnSSL_Init_SSL(CONNECTION *c)
437 "Can't initialize SSL context, OpenSSL initialization failed at startup!");
440 assert(c->ssl_state.ssl == NULL);
441 assert(c->ssl_state.fingerprint == NULL);
443 c->ssl_state.ssl = SSL_new(ssl_ctx);
444 if (!c->ssl_state.ssl) {
445 LogOpenSSLError("Failed to create SSL structure", NULL);
449 ret = SSL_set_fd(c->ssl_state.ssl, c->sock);
451 LogOpenSSLError("Failed to set SSL file descriptor", NULL);
456 #ifdef HAVE_LIBGNUTLS
457 ret = gnutls_set_default_priority(c->ssl_state.gnutls_session);
459 Log(LOG_ERR, "Failed to set GnuTLS default priority: %s",
460 gnutls_strerror(ret));
465 * The intermediate (long) cast is here to avoid a warning like:
466 * "cast to pointer from integer of different size" on 64-bit platforms.
467 * There doesn't seem to be an alternate GNUTLS API we could use instead, see e.g.
468 * http://www.mail-archive.com/help-gnutls@gnu.org/msg00286.html
470 gnutls_transport_set_ptr(c->ssl_state.gnutls_session, (gnutls_transport_ptr_t) (long) c->sock);
471 gnutls_certificate_server_set_request(c->ssl_state.gnutls_session, GNUTLS_CERT_REQUEST);
472 ret = gnutls_credentials_set(c->ssl_state.gnutls_session, GNUTLS_CRD_CERTIFICATE, x509_cred);
474 Log(LOG_ERR, "Failed to set SSL credentials: %s", gnutls_strerror(ret));
478 gnutls_dh_set_prime_bits(c->ssl_state.gnutls_session, DH_BITS_MIN);
480 Conn_OPTION_ADD(c, CONN_SSL);
486 ConnSSL_PrepareConnect(CONNECTION *c, UNUSED CONF_SERVER *s)
489 #ifdef HAVE_LIBGNUTLS
492 err = gnutls_init(&c->ssl_state.gnutls_session, GNUTLS_CLIENT);
494 Log(LOG_ERR, "Failed to initialize new SSL session: %s",
495 gnutls_strerror(err));
499 ret = ConnSSL_Init_SSL(c);
502 Conn_OPTION_ADD(c, CONN_SSL_CONNECT);
504 assert(c->ssl_state.ssl);
505 SSL_set_verify(c->ssl_state.ssl, SSL_VERIFY_NONE, NULL);
512 * Check and handle error return codes after failed calls to SSL functions.
515 * SSL_connect(), SSL_accept(), SSL_do_handshake(), SSL_read(), SSL_peek(), or
516 * SSL_write() on ssl.
519 * gnutlsssl_read(), gnutls_write() or gnutls_handshake().
521 * @param c The connection handle.
522 * @prarm code The return code.
523 * @param fname The name of the function in which the error occurred.
524 * @return -1 on fatal errors, 0 if we can try again later.
527 ConnSSL_HandleError(CONNECTION * c, const int code, const char *fname)
530 int ret = SSL_ERROR_SYSCALL;
531 unsigned long sslerr;
532 int real_errno = errno;
534 ret = SSL_get_error(c->ssl_state.ssl, code);
537 case SSL_ERROR_WANT_READ:
538 io_event_del(c->sock, IO_WANTWRITE);
539 Conn_OPTION_ADD(c, CONN_SSL_WANT_READ);
540 return 0; /* try again later */
541 case SSL_ERROR_WANT_WRITE:
542 io_event_del(c->sock, IO_WANTREAD);
543 Conn_OPTION_ADD(c, CONN_SSL_WANT_WRITE); /* fall through */
545 return 0; /* try again later */
546 case SSL_ERROR_ZERO_RETURN:
547 LogDebug("SSL connection shut down normally.");
549 case SSL_ERROR_SYSCALL:
550 /* SSL_ERROR_WANT_CONNECT, SSL_ERROR_WANT_ACCEPT,
551 * and SSL_ERROR_WANT_X509_LOOKUP */
552 sslerr = ERR_get_error();
554 Log(LOG_ERR, "SSL error: %s [in %s()]!",
555 ERR_error_string(sslerr, NULL), fname);
557 switch (code) { /* EOF that violated protocol */
560 "SSL error, client disconnected [in %s()]!",
563 case -1: /* low level socket I/O error, check errno */
564 Log(LOG_ERR, "SSL error: %s [in %s()]!",
565 strerror(real_errno), fname);
570 LogOpenSSLError("SSL protocol error", fname);
573 Log(LOG_ERR, "Unknown SSL error %d [in %s()]!", ret, fname);
578 #ifdef HAVE_LIBGNUTLS
581 case GNUTLS_E_INTERRUPTED:
582 if (gnutls_record_get_direction(c->ssl_state.gnutls_session)) {
583 Conn_OPTION_ADD(c, CONN_SSL_WANT_WRITE);
584 io_event_del(c->sock, IO_WANTREAD);
586 Conn_OPTION_ADD(c, CONN_SSL_WANT_READ);
587 io_event_del(c->sock, IO_WANTWRITE);
592 if (gnutls_error_is_fatal(code)) {
593 Log(LOG_ERR, "SSL error: %s [%s].",
594 gnutls_strerror(code), fname);
605 ConnSSL_LogCertInfo( CONNECTION *c )
608 SSL *ssl = c->ssl_state.ssl;
612 Log(LOG_INFO, "Connection %d: initialized %s using cipher %s.",
613 c->sock, SSL_get_version(ssl), SSL_get_cipher(ssl));
615 #ifdef HAVE_LIBGNUTLS
616 gnutls_session_t sess = c->ssl_state.gnutls_session;
617 gnutls_cipher_algorithm_t cipher = gnutls_cipher_get(sess);
619 Log(LOG_INFO, "Connection %d: initialized %s using cipher %s-%s.",
621 gnutls_protocol_get_name(gnutls_protocol_get_version(sess)),
622 gnutls_cipher_get_name(cipher),
623 gnutls_mac_get_name(gnutls_mac_get(sess)));
629 Accept incoming SSL connection.
631 1: SSL Connection established
633 -1: SSL Connection not established due to fatal error.
636 ConnSSL_Accept( CONNECTION *c )
639 if (!Conn_OPTION_ISSET(c, CONN_SSL)) {
640 #ifdef HAVE_LIBGNUTLS
641 int err = gnutls_init(&c->ssl_state.gnutls_session, GNUTLS_SERVER);
643 Log(LOG_ERR, "Failed to initialize new SSL session: %s",
644 gnutls_strerror(err));
648 LogDebug("Initializing SSL data ...");
649 if (!ConnSSL_Init_SSL(c))
652 return ConnectAccept(c, false );
657 ConnSSL_Connect( CONNECTION *c )
661 assert(c->ssl_state.ssl);
663 assert(Conn_OPTION_ISSET(c, CONN_SSL));
664 return ConnectAccept(c, true);
668 ConnSSL_InitCertFp( CONNECTION *c )
670 const char hex[] = "0123456789abcdef";
674 unsigned char digest[EVP_MAX_MD_SIZE];
675 unsigned int digest_size;
678 cert = SSL_get_peer_certificate(c->ssl_state.ssl);
682 if (!X509_digest(cert, EVP_sha1(), digest, &digest_size)) {
688 #endif /* HAVE_LIBSSL */
689 #ifdef HAVE_LIBGNUTLS
690 gnutls_x509_crt_t cert;
691 unsigned int cert_list_size;
692 const gnutls_datum_t *cert_list;
693 unsigned char digest[MAX_HASH_SIZE];
696 if (gnutls_certificate_type_get(c->ssl_state.gnutls_session) != GNUTLS_CRT_X509)
699 if (gnutls_x509_crt_init(&cert) != GNUTLS_E_SUCCESS)
703 cert_list = gnutls_certificate_get_peers(c->ssl_state.gnutls_session,
706 gnutls_x509_crt_deinit(cert);
710 if (gnutls_x509_crt_import(cert, &cert_list[0], GNUTLS_X509_FMT_DER) != GNUTLS_E_SUCCESS) {
711 gnutls_x509_crt_deinit(cert);
715 digest_size = sizeof(digest);
716 if (gnutls_x509_crt_get_fingerprint(cert, GNUTLS_DIG_SHA1, digest, &digest_size)) {
717 gnutls_x509_crt_deinit(cert);
721 gnutls_x509_crt_deinit(cert);
722 #endif /* HAVE_LIBGNUTLS */
724 assert(c->ssl_state.fingerprint == NULL);
726 c->ssl_state.fingerprint = malloc(CERTFP_LEN);
727 if (!c->ssl_state.fingerprint)
730 for (i = 0; i < (int)digest_size; i++) {
731 c->ssl_state.fingerprint[i * 2] = hex[digest[i] / 16];
732 c->ssl_state.fingerprint[i * 2 + 1] = hex[digest[i] % 16];
734 c->ssl_state.fingerprint[i * 2] = '\0';
739 /* accept/connect wrapper. if connect is true, connect to peer, otherwise wait for incoming connection */
741 ConnectAccept( CONNECTION *c, bool connect)
745 SSL *ssl = c->ssl_state.ssl;
748 ret = connect ? SSL_connect(ssl) : SSL_accept(ssl);
750 return ConnSSL_HandleError(c, ret, connect ? "SSL_connect": "SSL_accept");
752 #ifdef HAVE_LIBGNUTLS
754 ret = gnutls_handshake(c->ssl_state.gnutls_session);
756 return ConnSSL_HandleError(c, ret, "gnutls_handshake");
758 (void)ConnSSL_InitCertFp(c);
760 Conn_OPTION_DEL(c, (CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ|CONN_SSL_CONNECT));
761 ConnSSL_LogCertInfo(c);
763 Conn_StartLogin(CONNECTION2ID(c));
769 ConnSSL_Write(CONNECTION *c, const void *buf, size_t count)
773 Conn_OPTION_DEL(c, CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ);
777 bw = (ssize_t) SSL_write(c->ssl_state.ssl, buf, count);
779 #ifdef HAVE_LIBGNUTLS
780 bw = gnutls_write(c->ssl_state.gnutls_session, buf, count);
784 if (ConnSSL_HandleError( c, bw, "ConnSSL_Write") == 0)
785 errno = EAGAIN; /* try again */
791 ConnSSL_Read(CONNECTION *c, void * buf, size_t count)
795 Conn_OPTION_DEL(c, CONN_SSL_WANT_WRITE|CONN_SSL_WANT_READ);
797 br = (ssize_t) SSL_read(c->ssl_state.ssl, buf, count);
798 if (br > 0) /* on EOF we have to call ConnSSL_HandleError(), see SSL_read(3) */
801 #ifdef HAVE_LIBGNUTLS
802 br = gnutls_read(c->ssl_state.gnutls_session, buf, count);
803 if (br >= 0) /* on EOF we must _not_ call ConnSSL_HandleError, see gnutls_record_recv(3) */
806 /* error on read: switch ConnSSL_HandleError() return values -> 0 is "try again", so return -1 and set EAGAIN */
807 if (ConnSSL_HandleError(c, br, "ConnSSL_Read") == 0) {
816 ConnSSL_GetCipherInfo(CONNECTION *c, char *buf, size_t len)
820 SSL *ssl = c->ssl_state.ssl;
825 SSL_CIPHER_description(SSL_get_current_cipher(ssl), buf, len);
826 nl = strchr(buf, '\n');
831 #ifdef HAVE_LIBGNUTLS
832 if (Conn_OPTION_ISSET(c, CONN_SSL)) {
833 const char *name_cipher, *name_mac, *name_proto, *name_keyexchange;
836 gnutls_session_t sess = c->ssl_state.gnutls_session;
837 gnutls_cipher_algorithm_t cipher = gnutls_cipher_get(sess);
838 name_cipher = gnutls_cipher_get_name(cipher);
839 name_mac = gnutls_mac_get_name(gnutls_mac_get(sess));
840 keysize = gnutls_cipher_get_key_size(cipher) * 8;
841 name_proto = gnutls_protocol_get_name(gnutls_protocol_get_version(sess));
842 name_keyexchange = gnutls_kx_get_name(gnutls_kx_get(sess));
844 return snprintf(buf, len, "%s-%s%15s Kx=%s Enc=%s(%u) Mac=%s",
845 name_cipher, name_mac, name_proto, name_keyexchange, name_cipher, keysize, name_mac) > 0;
852 ConnSSL_GetCertFp(CONNECTION *c)
854 return c->ssl_state.fingerprint;
858 ConnSSL_SetCertFp(CONNECTION *c, const char *fingerprint)
861 c->ssl_state.fingerprint = strdup(fingerprint);
862 return c->ssl_state.fingerprint != NULL;
867 ConnSSL_InitLibrary(void)
872 #endif /* SSL_SUPPORT */