Specific error for suites in common but none good

ChangeLog

@@ -6,6 +6,11 @@ Features
    * Certificate selection based on signature hash, prefering SHA-1 over SHA-2
      for pre-1.2 clients when multiple certificates are available.
 
+Changes
+   * A specific error is now returned when there are ciphersuites in common
+     but none of them is usable due to external factors such as no certificate
+     with a suitable (extended)KeyUsage or curvem or no PSK set.
+
 = PolarSSL 1.3.9 released 2014-10-20
 Security
    * Lowest common hash was selected from signature_algorithms extension in

include/polarssl/error.h

@@ -91,7 +91,7 @@
  * ECP       4   8 (Started from top)
  * MD        5   4
  * CIPHER    6   6
- * SSL       6   10 (Started from top)
+ * SSL       6   11 (Started from top)
  * SSL       7   31
  *
  * Module dependent error code (5 bits 0x.00.-0x.F8.)

include/polarssl/ssl.h

@@ -146,6 +146,7 @@
 #define POLARSSL_ERR_SSL_INTERNAL_ERROR                    -0x6C00  /**< Internal error (eg, unexpected failure in lower-level module) */
 #define POLARSSL_ERR_SSL_COUNTER_WRAPPING                  -0x6B80  /**< A counter would wrap (eg, too many messages exchanged). */
 #define POLARSSL_ERR_SSL_WAITING_SERVER_HELLO_RENEGO       -0x6B00  /**< Unexpected message at ServerHello in renegotiation. */
+#define POLARSSL_ERR_SSL_NO_USABLE_CIPHERSUITE             -0x6A80  /**< None of the common ciphersuites is usable (eg, no suitable certificate) */
 
 /*
  * Various constants

library/error.c

@@ -452,6 +452,8 @@ void polarssl_strerror( int ret, char *buf, size_t buflen )
             snprintf( buf, buflen, "SSL - A counter would wrap (eg, too many messages exchanged)" );
         if( use_ret == -(POLARSSL_ERR_SSL_WAITING_SERVER_HELLO_RENEGO) )
             snprintf( buf, buflen, "SSL - Unexpected message at ServerHello in renegotiation" );
+        if( use_ret == -(POLARSSL_ERR_SSL_NO_USABLE_CIPHERSUITE) )
+            snprintf( buf, buflen, "SSL - None of the common ciphersuites is usable (eg, no suitable certificate)" );
 #endif /* POLARSSL_SSL_TLS_C */
 
 #if defined(POLARSSL_X509_USE_C) || defined(POLARSSL_X509_CREATE_C)

library/ssl_srv.c

@@ -903,7 +903,7 @@ static int ssl_ciphersuite_match( ssl_context *ssl, int suite_id,
 #if defined(POLARSSL_SSL_SRV_SUPPORT_SSLV2_CLIENT_HELLO)
 static int ssl_parse_client_hello_v2( ssl_context *ssl )
 {
-    int ret;
+    int ret, got_common_suite;
     unsigned int i, j;
     size_t n;
     unsigned int ciph_len, sess_len, chal_len;
@@ -1072,6 +1072,7 @@ static int ssl_parse_client_hello_v2( ssl_context *ssl )
         }
     }
 
+    got_common_suite = 0;
     ciphersuites = ssl->ciphersuite_list[ssl->minor_ver];
     ciphersuite_info = NULL;
 #if defined(POLARSSL_SSL_SRV_RESPECT_CLIENT_PREFERENCE)
@@ -1089,6 +1090,8 @@ static int ssl_parse_client_hello_v2( ssl_context *ssl )
                 p[2] != ( ( ciphersuites[i]      ) & 0xFF ) )
                 continue;
 
+            got_common_suite = 1;
+
             if( ( ret = ssl_ciphersuite_match( ssl, ciphersuites[i],
                                                &ciphersuite_info ) ) != 0 )
                 return( ret );
@@ -1098,9 +1101,17 @@ static int ssl_parse_client_hello_v2( ssl_context *ssl )
         }
     }
 
+    if( got_common_suite )
+    {
+        SSL_DEBUG_MSG( 1, ( "got ciphersuites in common, "
+                            "but none of them usable" ) );
+        return( POLARSSL_ERR_SSL_NO_USABLE_CIPHERSUITE );
+    }
+    else
+    {
         SSL_DEBUG_MSG( 1, ( "got no ciphersuites in common" ) );
-
         return( POLARSSL_ERR_SSL_NO_CIPHER_CHOSEN );
+    }
 
 have_ciphersuite_v2:
     ssl->session_negotiate->ciphersuite = ciphersuites[i];
@@ -1132,7 +1143,7 @@ have_ciphersuite_v2:
 
 static int ssl_parse_client_hello( ssl_context *ssl )
 {
-    int ret;
+    int ret, got_common_suite;
     unsigned int i, j;
     size_t n;
     unsigned int ciph_len, sess_len;
@@ -1552,6 +1563,7 @@ static int ssl_parse_client_hello( ssl_context *ssl )
      * (At the end because we need information from the EC-based extensions
      * and certificate from the SNI callback triggered by the SNI extension.)
      */
+    got_common_suite = 0;
     ciphersuites = ssl->ciphersuite_list[ssl->minor_ver];
     ciphersuite_info = NULL;
 #if defined(POLARSSL_SSL_SRV_RESPECT_CLIENT_PREFERENCE)
@@ -1568,6 +1580,8 @@ static int ssl_parse_client_hello( ssl_context *ssl )
                 p[1] != ( ( ciphersuites[i]      ) & 0xFF ) )
                 continue;
 
+            got_common_suite = 1;
+
             if( ( ret = ssl_ciphersuite_match( ssl, ciphersuites[i],
                                                &ciphersuite_info ) ) != 0 )
                 return( ret );
@@ -1577,12 +1591,19 @@ static int ssl_parse_client_hello( ssl_context *ssl )
         }
     }
 
+    if( got_common_suite )
+    {
+        SSL_DEBUG_MSG( 1, ( "got ciphersuites in common, "
+                            "but none of them usable" ) );
+        ssl_send_fatal_handshake_failure( ssl );
+        return( POLARSSL_ERR_SSL_NO_USABLE_CIPHERSUITE );
+    }
+    else
+    {
         SSL_DEBUG_MSG( 1, ( "got no ciphersuites in common" ) );
-
+        ssl_send_fatal_handshake_failure( ssl );
-    if( ( ret = ssl_send_fatal_handshake_failure( ssl ) ) != 0 )
-        return( ret );
-
         return( POLARSSL_ERR_SSL_NO_CIPHER_CHOSEN );
+    }
 
 have_ciphersuite:
     ssl->session_negotiate->ciphersuite = ciphersuites[i];

tests/ssl-opt.sh

@@ -1562,7 +1562,7 @@ run_test    "PSK callback: psk, no callback" \
             "$P_CLI force_ciphersuite=TLS-PSK-WITH-AES-128-CBC-SHA \
             psk_identity=foo psk=abc123" \
             0 \
-            -S "SSL - The server has no ciphersuites in common" \
+            -S "SSL - None of the common ciphersuites is usable" \
             -S "SSL - Unknown identity received" \
             -S "SSL - Verification of the message MAC failed"
 
@@ -1571,7 +1571,7 @@ run_test    "PSK callback: no psk, no callback" \
             "$P_CLI force_ciphersuite=TLS-PSK-WITH-AES-128-CBC-SHA \
             psk_identity=foo psk=abc123" \
             1 \
-            -s "SSL - The server has no ciphersuites in common" \
+            -s "SSL - None of the common ciphersuites is usable" \
             -S "SSL - Unknown identity received" \
             -S "SSL - Verification of the message MAC failed"
 
@@ -1580,7 +1580,7 @@ run_test    "PSK callback: callback overrides other settings" \
             "$P_CLI force_ciphersuite=TLS-PSK-WITH-AES-128-CBC-SHA \
             psk_identity=foo psk=abc123" \
             1 \
-            -S "SSL - The server has no ciphersuites in common" \
+            -S "SSL - None of the common ciphersuites is usable" \
             -s "SSL - Unknown identity received" \
             -S "SSL - Verification of the message MAC failed"
 
@@ -1589,7 +1589,7 @@ run_test    "PSK callback: first id matches" \
             "$P_CLI force_ciphersuite=TLS-PSK-WITH-AES-128-CBC-SHA \
             psk_identity=abc psk=dead" \
             0 \
-            -S "SSL - The server has no ciphersuites in common" \
+            -S "SSL - None of the common ciphersuites is usable" \
             -S "SSL - Unknown identity received" \
             -S "SSL - Verification of the message MAC failed"
 
@@ -1598,7 +1598,7 @@ run_test    "PSK callback: second id matches" \
             "$P_CLI force_ciphersuite=TLS-PSK-WITH-AES-128-CBC-SHA \
             psk_identity=def psk=beef" \
             0 \
-            -S "SSL - The server has no ciphersuites in common" \
+            -S "SSL - None of the common ciphersuites is usable" \
             -S "SSL - Unknown identity received" \
             -S "SSL - Verification of the message MAC failed"
 
@@ -1607,7 +1607,7 @@ run_test    "PSK callback: no match" \
             "$P_CLI force_ciphersuite=TLS-PSK-WITH-AES-128-CBC-SHA \
             psk_identity=ghi psk=beef" \
             1 \
-            -S "SSL - The server has no ciphersuites in common" \
+            -S "SSL - None of the common ciphersuites is usable" \
             -s "SSL - Unknown identity received" \
             -S "SSL - Verification of the message MAC failed"
 
@@ -1616,7 +1616,7 @@ run_test    "PSK callback: wrong key" \
             "$P_CLI force_ciphersuite=TLS-PSK-WITH-AES-128-CBC-SHA \
             psk_identity=abc psk=beef" \
             1 \
-            -S "SSL - The server has no ciphersuites in common" \
+            -S "SSL - None of the common ciphersuites is usable" \
             -S "SSL - Unknown identity received" \
             -s "SSL - Verification of the message MAC failed"