Add support for multiple server certificates

include/polarssl/ssl.h

@@ -492,6 +492,9 @@ struct _ssl_handshake_params
 #if defined(POLARSSL_ECDH_C) || defined(POLARSSL_ECDSA_C)
     int ec_curve;                       /*!<  Selected elliptic curve */
 #endif
+#if defined(POLARSSL_X509_CRT_PARSE_C)
+    ssl_key_cert *key_cert;             /*!<  Own key/cert in use     */
+#endif
 
     /*
      * Checksum contexts
@@ -1517,12 +1520,14 @@ md_type_t ssl_md_alg_from_hash( unsigned char hash );
 #if defined(POLARSSL_X509_CRT_PARSE_C)
 static inline pk_context *ssl_own_key( ssl_context *ssl )
 {
-    return( ssl->key_cert == NULL ? NULL : ssl->key_cert->key );
+    return( ssl->handshake->key_cert == NULL ? NULL
+            : ssl->handshake->key_cert->key );
 }
 
 static inline x509_crt *ssl_own_cert( ssl_context *ssl )
 {
-    return( ssl->key_cert == NULL ? NULL : ssl->key_cert->cert );
+    return( ssl->handshake->key_cert == NULL ? NULL
+            : ssl->handshake->key_cert->cert );
 }
 #endif /* POLARSSL_X509_CRT_PARSE_C */
 

library/ssl_srv.c

@@ -1271,7 +1271,8 @@ static int ssl_parse_client_hello( ssl_context *ssl )
 
     /*
      * Search for a matching ciphersuite
-     * (At the end because we need information from the EC-based extensions)
+     * (At the end because we need information from the EC-based extensions
+     * and certificate from the SNI callback triggered by the SNI extension.)
      */
     ciphersuites = ssl->ciphersuite_list[ssl->minor_ver];
     for( i = 0; ciphersuites[i] != 0; i++ )
@@ -1301,14 +1302,32 @@ static int ssl_parse_client_hello( ssl_context *ssl )
                     continue;
 #endif
 
-                /* If ciphersuite requires us to have a private key of a
+#if defined(POLARSSL_X509_CRT_PARSE_C)
-                 * certain type, make sure we do */
+                /*
-#if defined(POLARSSL_PK_C)
+                 * Final check: if ciphersuite requires us to have a
+                 * certificate/key of a particular type:
+                 * - select the appropriate certificate if we have one, or
+                 * - try the next ciphersuite if we don't
+                 * This must be done last since we modify the key_cert list.
+                 */
                 pk_alg = ssl_get_ciphersuite_sig_pk_alg( ciphersuite_info );
-                if( pk_alg != POLARSSL_PK_NONE &&
+                if( pk_alg != POLARSSL_PK_NONE )
-                    ( ssl_own_key( ssl ) == NULL ||
+                {
-                      ! pk_can_do( ssl_own_key( ssl ), pk_alg ) ) )
+                    ssl_key_cert *good = NULL;
-                    continue;
+                    ssl_key_cert *cur = ssl->key_cert;
+
+                    while( cur != NULL && good == NULL )
+                    {
+                        if( pk_can_do( cur->key, pk_alg ) )
+                            good = cur;
+                        cur = cur->next;
+                    }
+
+                    if( good == NULL )
+                        continue;
+                    else
+                        ssl->handshake->key_cert = good;
+                }
 #endif
 
                 goto have_ciphersuite;

library/ssl_tls.c

@@ -3849,6 +3849,10 @@ int ssl_handshake( ssl_context *ssl )
 
     SSL_DEBUG_MSG( 2, ( "=> handshake" ) );
 
+#if defined(POLARSSL_X509_CRT_PARSE_C)
+    ssl->handshake->key_cert = ssl->key_cert;
+#endif
+
     while( ssl->state != SSL_HANDSHAKE_OVER )
     {
         ret = ssl_handshake_step( ssl );

programs/ssl/ssl_server2.c

@@ -56,6 +56,8 @@
 #define DFL_CA_PATH             ""
 #define DFL_CRT_FILE            ""
 #define DFL_KEY_FILE            ""
+#define DFL_CRT_FILE2           ""
+#define DFL_KEY_FILE2           ""
 #define DFL_PSK                 ""
 #define DFL_PSK_IDENTITY        "Client_identity"
 #define DFL_FORCE_CIPHER        0
@@ -91,8 +93,10 @@ struct options
     int debug_level;            /* level of debugging                       */
     const char *ca_file;        /* the file with the CA certificate(s)      */
     const char *ca_path;        /* the path with the CA certificate(s) reside */
-    const char *crt_file;       /* the file with the client certificate     */
+    const char *crt_file;       /* the file with the server certificate     */
-    const char *key_file;       /* the file with the client key             */
+    const char *key_file;       /* the file with the server key             */
+    const char *crt_file2;      /* the file with the 2nd server certificate */
+    const char *key_file2;      /* the file with the 2nd server key         */
     const char *psk;            /* the pre-shared key                       */
     const char *psk_identity;   /* the pre-shared key identity              */
     int force_ciphersuite[2];   /* protocol/ciphersuite to use, or all      */
@@ -114,6 +118,56 @@ static void my_debug( void *ctx, int level, const char *str )
     }
 }
 
+#if defined(POLARSSL_X509_CRT_PARSE_C)
+static int parse_cert_key( x509_crt *crt, const char *crt_file,
+                           pk_context *key, const char *key_file )
+{
+    int ret;
+
+#if defined(POLARSSL_FS_IO)
+    if( strlen( crt_file ) )
+        ret = x509_crt_parse_file( crt, crt_file );
+    else
+#endif
+#if defined(POLARSSL_CERTS_C)
+        ret = x509_crt_parse( crt, (const unsigned char *) test_srv_crt,
+                              strlen( test_srv_crt ) );
+#else
+    {
+        ret = 1;
+        printf("POLARSSL_CERTS_C not defined.");
+    }
+#endif
+    if( ret != 0 )
+    {
+        printf( " failed\n  !  x509_crt_parse returned -0x%x\n\n", -ret );
+        return( ret );
+    }
+
+#if defined(POLARSSL_FS_IO)
+    if( strlen( key_file ) )
+        ret = pk_parse_keyfile( key, key_file, "" );
+    else
+#endif
+#if defined(POLARSSL_CERTS_C)
+        ret = pk_parse_key( key, (const unsigned char *) test_srv_key,
+                strlen( test_srv_key ), NULL, 0 );
+#else
+    {
+        ret = 1;
+        printf("POLARSSL_CERTS_C not defined.");
+    }
+#endif
+    if( ret != 0 )
+    {
+        printf( " failed\n  !  pk_parse_key returned -0x%x\n\n", -ret );
+        return( ret );
+    }
+
+    return( 0 );
+}
+#endif /* POLARSSL_X509_CRT_PARSE_C */
+
 #if defined(POLARSSL_X509_CRT_PARSE_C)
 #if defined(POLARSSL_FS_IO)
 #define USAGE_IO \
@@ -123,7 +177,10 @@ static void my_debug( void *ctx, int level, const char *str )
     "                        default: \"\" (pre-loaded) (overrides ca_file)\n" \
     "    crt_file=%%s         Your own cert and chain (in bottom to top order, top may be omitted)\n" \
     "                        default: \"\" (pre-loaded)\n" \
-    "    key_file=%%s         default: \"\" (pre-loaded)\n"
+    "    key_file=%%s         default: \"\" (pre-loaded)\n" \
+    "    crt_file2=%%s        Your second cert and chain (in bottom to top order, top may be omitted)\n" \
+    "                        default: \"\" (pre-loaded)\n" \
+    "    key_file2=%%s        default: \"\" (pre-loaded)\n"
 #else
 #define USAGE_IO \
     "\n"                                                    \
@@ -212,6 +269,8 @@ int main( int argc, char *argv[] )
     x509_crt cacert;
     x509_crt srvcert;
     pk_context pkey;
+    x509_crt srvcert2;
+    pk_context pkey2;
 #endif
 #if defined(POLARSSL_SSL_CACHE_C)
     ssl_cache_context cache;
@@ -237,6 +296,8 @@ int main( int argc, char *argv[] )
     x509_crt_init( &cacert );
     x509_crt_init( &srvcert );
     pk_init( &pkey );
+    x509_crt_init( &srvcert2 );
+    pk_init( &pkey2 );
 #endif
 #if defined(POLARSSL_SSL_CACHE_C)
     ssl_cache_init( &cache );
@@ -270,6 +331,8 @@ int main( int argc, char *argv[] )
     opt.ca_path             = DFL_CA_PATH;
     opt.crt_file            = DFL_CRT_FILE;
     opt.key_file            = DFL_KEY_FILE;
+    opt.crt_file2           = DFL_CRT_FILE2;
+    opt.key_file2           = DFL_KEY_FILE2;
     opt.psk                 = DFL_PSK;
     opt.psk_identity        = DFL_PSK_IDENTITY;
     opt.force_ciphersuite[0]= DFL_FORCE_CIPHER;
@@ -308,6 +371,10 @@ int main( int argc, char *argv[] )
             opt.crt_file = q;
         else if( strcmp( p, "key_file" ) == 0 )
             opt.key_file = q;
+        else if( strcmp( p, "crt_file2" ) == 0 )
+            opt.crt_file2 = q;
+        else if( strcmp( p, "key_file2" ) == 0 )
+            opt.key_file2 = q;
         else if( strcmp( p, "psk" ) == 0 )
             opt.psk = q;
         else if( strcmp( p, "psk_identity" ) == 0 )
@@ -550,45 +617,11 @@ int main( int argc, char *argv[] )
     printf( "  . Loading the server cert. and key..." );
     fflush( stdout );
 
-#if defined(POLARSSL_FS_IO)
+    if( parse_cert_key( &srvcert, opt.crt_file, &pkey, opt.key_file ) != 0 )
-    if( strlen( opt.crt_file ) )
-        ret = x509_crt_parse_file( &srvcert, opt.crt_file );
-    else
-#endif
-#if defined(POLARSSL_CERTS_C)
-        ret = x509_crt_parse( &srvcert, (const unsigned char *) test_srv_crt,
-                              strlen( test_srv_crt ) );
-#else
-    {
-        ret = 1;
-        printf("POLARSSL_CERTS_C not defined.");
-    }
-#endif
-    if( ret != 0 )
-    {
-        printf( " failed\n  !  x509_crt_parse returned -0x%x\n\n", -ret );
         goto exit;
-    }
 
-#if defined(POLARSSL_FS_IO)
+    if( parse_cert_key( &srvcert2, opt.crt_file2, &pkey2, opt.key_file2 ) != 0 )
-    if( strlen( opt.key_file ) )
-        ret = pk_parse_keyfile( &pkey, opt.key_file, "" );
-    else
-#endif
-#if defined(POLARSSL_CERTS_C)
-        ret = pk_parse_key( &pkey, (const unsigned char *) test_srv_key,
-                strlen( test_srv_key ), NULL, 0 );
-#else
-    {
-        ret = 1;
-        printf("POLARSSL_CERTS_C not defined.");
-    }
-#endif
-    if( ret != 0 )
-    {
-        printf( " failed\n  !  pk_parse_key returned -0x%x\n\n", -ret );
         goto exit;
-    }
 
     printf( " ok\n" );
 #endif /* POLARSSL_X509_CRT_PARSE_C */
@@ -647,6 +680,7 @@ int main( int argc, char *argv[] )
 #if defined(POLARSSL_X509_CRT_PARSE_C)
     ssl_set_ca_chain( &ssl, &cacert, NULL, NULL );
     ssl_set_own_cert( &ssl, &srvcert, &pkey );
+    ssl_set_own_cert( &ssl, &srvcert2, &pkey2 );
 #endif
 
 #if defined(POLARSSL_KEY_EXCHANGE_PSK_ENABLED)
@@ -875,9 +909,11 @@ exit:
 
     net_close( client_fd );
 #if defined(POLARSSL_X509_CRT_PARSE_C)
-    x509_crt_free( &srvcert );
     x509_crt_free( &cacert );
+    x509_crt_free( &srvcert );
     pk_free( &pkey );
+    x509_crt_free( &srvcert2 );
+    pk_free( &pkey2 );
 #endif
 
     ssl_free( &ssl );