Cipher list selection for GnuTLS bug162-SSLCipherList
authorAlexander Barton <alex@barton.de>
Sun, 15 Sep 2013 15:57:41 +0000 (17:57 +0200)
committerAlexander Barton <alex@barton.de>
Sun, 15 Sep 2013 15:57:47 +0000 (17:57 +0200)
This patch implements the missing functionality for cipher list selection
using GnuTLS (our OpenSSL code has this already).

doc/sample-ngircd.conf.tmpl
man/ngircd.conf.5.tmpl
src/ngircd/conn-ssl.c

index a4dbf86..1bdf01e 100644 (file)
        # SSL Server Key Certificate
        ;CertFile = :ETCDIR:/ssl/server-cert.pem
 
-       # Select cipher suites allowed for SSL/TLS connections (OpenSSL only).
-       # This defaults to the empty string, so all supported ciphers are
-       # allowed. Please see 'man 1ssl ciphers' for details.
-       # The example below only allows "high strength" cipher suites, disables
-       # the ones without authentication, and sorts by strength:
+       # Select cipher suites allowed for SSL/TLS connections. This defaults
+       # to the empty string, so all supported ciphers are allowed. Please
+       # see 'man 1ssl ciphers' (OpenSSL) and 'man 3 gnutls_priority_init'
+       # (GnuTLS) for details.
+       # For example, this setting allows only "high strength" cipher suites,
+       # disables the ones without authentication, and sorts by strength:
+       # For OpenSSL:
        ;CipherList = HIGH:!aNULL:@STRENGTH
+       # For GnuTLS:
+       ;CipherList = SECURE128
 
        # Diffie-Hellman parameters
        ;DHFile = :ETCDIR:/ssl/dhparams.pem
index 263dec0..862c142 100644 (file)
@@ -367,11 +367,13 @@ when it is compiled with support for SSL using OpenSSL or GnuTLS!
 SSL Certificate file of the private server key.
 .TP
 \fBCipherList\fR (string)
-OpenSSL only: Select cipher suites allowed for SSL/TLS connections. This
-defaults to the empty string, so all supported ciphers are allowed. Please see
-'man 1ssl ciphers' for details. This setting allows only "high strength" cipher
-suites, disables the ones without authentication, and sorts by strength, for
-example: "HIGH:!aNULL:@STRENGTH".
+Select cipher suites allowed for SSL/TLS connections. This defaults to the
+empty string, so all supported ciphers are allowed.
+Please see 'man 1ssl ciphers' (OpenSSL) and 'man 3 gnutls_priority_init'
+(GnuTLS) for details.
+For example, this setting allows only "high strength" cipher suites, disables
+the ones without authentication, and sorts by strength:
+"HIGH:!aNULL:@STRENGTH" (OpenSSL), "SECURE128" (GnuTLS).
 .TP
 \fBDHFile\fR (string)
 Name of the Diffie-Hellman Parameter file. Can be created with GnuTLS
index a978967..b16c6b9 100644 (file)
@@ -58,6 +58,7 @@ static bool ConnSSL_LoadServerKey_openssl PARAMS(( SSL_CTX *c ));
 
 static gnutls_certificate_credentials_t x509_cred;
 static gnutls_dh_params_t dh_params;
+static gnutls_priority_t priorities_cache;
 static bool ConnSSL_LoadServerKey_gnutls PARAMS(( void ));
 #endif
 
@@ -308,12 +309,12 @@ ConnSSL_InitLibrary( void )
        if(Conf_SSLOptions.CipherList && *Conf_SSLOptions.CipherList) {
                if(SSL_CTX_set_cipher_list(newctx, Conf_SSLOptions.CipherList) == 0 ) {
                        Log(LOG_ERR,
-                           "Failed to apply SSL cipher list \"%s\"!",
+                           "Failed to apply OpenSSL cipher list \"%s\"!",
                            Conf_SSLOptions.CipherList);
                        goto out;
                } else {
                        Log(LOG_INFO,
-                           "Successfully applied SSL cipher list: \"%s\".",
+                           "Successfully applied OpenSSL cipher list \"%s\".",
                            Conf_SSLOptions.CipherList);
                }
        }
@@ -341,29 +342,43 @@ out:
                return false;
        }
 
-       if(Conf_SSLOptions.CipherList != NULL) {
-               Log(LOG_ERR,
-                   "Failed to apply SSL cipher list \"%s\": Not implemented for GnuTLS!",
-                   Conf_SSLOptions.CipherList);
-               array_free(&Conf_SSLOptions.ListenPorts);
-               return false;
-       }
-
        err = gnutls_global_init();
        if (err) {
                Log(LOG_ERR, "Failed to initialize GnuTLS: %s",
                    gnutls_strerror(err));
-               array_free(&Conf_SSLOptions.ListenPorts);
-               return false;
+               goto out;
        }
-       if (!ConnSSL_LoadServerKey_gnutls()) {
-               array_free(&Conf_SSLOptions.ListenPorts);
-               return false;
+
+       if (!ConnSSL_LoadServerKey_gnutls())
+               goto out;
+
+       if(Conf_SSLOptions.CipherList && *Conf_SSLOptions.CipherList) {
+               err = gnutls_priority_init(&priorities_cache,
+                                          Conf_SSLOptions.CipherList, NULL);
+               if (err != GNUTLS_E_SUCCESS) {
+                       Log(LOG_ERR,
+                           "Failed to apply GnuTLS cipher list \"%s\"!",
+                           Conf_SSLOptions.CipherList);
+                       goto out;
+               }
+               Log(LOG_INFO,
+                   "Successfully applied GnuTLS cipher list \"%s\".",
+                   Conf_SSLOptions.CipherList);
+       } else {
+               err = gnutls_priority_init(&priorities_cache, "NORMAL", NULL);
+               if (err != GNUTLS_E_SUCCESS) {
+                       Log(LOG_ERR,
+                           "Failed to apply GnuTLS cipher list \"NORMAL\"!");
+                       goto out;
+               }
        }
 
        Log(LOG_INFO, "GnuTLS %s initialized.", gnutls_check_version(NULL));
        initialized = true;
        return true;
+out:
+       array_free(&Conf_SSLOptions.ListenPorts);
+       return false;
 #endif
 }
 
@@ -489,9 +504,9 @@ ConnSSL_Init_SSL(CONNECTION *c)
 #endif
 #ifdef HAVE_LIBGNUTLS
        Conn_OPTION_ADD(c, CONN_SSL);
-       ret = gnutls_set_default_priority(c->ssl_state.gnutls_session);
+       ret = gnutls_priority_set(c->ssl_state.gnutls_session, priorities_cache);
        if (ret != 0) {
-               Log(LOG_ERR, "Failed to set GnuTLS default priority: %s",
+               Log(LOG_ERR, "Failed to set GnuTLS session priorities: %s",
                    gnutls_strerror(ret));
                ConnSSL_Free(c);
                return false;