fix tls12 openssl/gnutls server fail

To test version negotiation with tls12 OpenSSL/GnuTLS server, If
`rsa_pss_rsae_*` were sent to server before `rsa_pkcs_*`, server
will return `rsa_pss_rsae_*` as key exchange sig alg. OpenSSL/GnuTLS
can work with this case. mbedTLS will fail due to `rsa_pss_rsae_*`
unsupported.

Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
diff --git a/library/ssl_misc.h b/library/ssl_misc.h
index 715d036..ff39075 100644
--- a/library/ssl_misc.h
+++ b/library/ssl_misc.h
@@ -1969,107 +1969,103 @@
     return( 0 );
 }
 
-#if defined(MBEDTLS_SSL_PROTO_TLS1_3)
 static inline int mbedtls_ssl_tls13_get_pk_type_and_md_alg_from_sig_alg(
     uint16_t sig_alg, mbedtls_pk_type_t *pk_type, mbedtls_md_type_t *md_alg )
 {
-    *pk_type = MBEDTLS_PK_NONE;
-    *md_alg = MBEDTLS_MD_NONE;
+    *pk_type = mbedtls_ssl_pk_alg_from_sig( sig_alg & 0xff );
+    *md_alg = mbedtls_ssl_md_alg_from_hash( ( sig_alg >> 8 ) & 0xff );
+
+    if( *pk_type != MBEDTLS_PK_NONE && *md_alg != MBEDTLS_MD_NONE )
+        return( 0 );
 
     switch( sig_alg )
     {
-#if defined(MBEDTLS_ECDSA_C)
-
-#if defined(MBEDTLS_SHA256_C) && defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED)
-        case MBEDTLS_TLS1_3_SIG_ECDSA_SECP256R1_SHA256:
-            *md_alg = MBEDTLS_MD_SHA256;
-            *pk_type = MBEDTLS_PK_ECDSA;
-            break;
-#endif /* MBEDTLS_SHA256_C && MBEDTLS_ECP_DP_SECP256R1_ENABLED */
-
-#if defined(MBEDTLS_SHA384_C) && defined(MBEDTLS_ECP_DP_SECP384R1_ENABLED)
-        case MBEDTLS_TLS1_3_SIG_ECDSA_SECP384R1_SHA384:
-            *md_alg = MBEDTLS_MD_SHA384;
-            *pk_type = MBEDTLS_PK_ECDSA;
-            break;
-#endif /* MBEDTLS_SHA384_C && MBEDTLS_ECP_DP_SECP384R1_ENABLED */
-
-#if defined(MBEDTLS_SHA512_C) && defined(MBEDTLS_ECP_DP_SECP521R1_ENABLED)
-        case MBEDTLS_TLS1_3_SIG_ECDSA_SECP521R1_SHA512:
-            *md_alg = MBEDTLS_MD_SHA512;
-            *pk_type = MBEDTLS_PK_ECDSA;
-            break;
-#endif /* MBEDTLS_SHA512_C && MBEDTLS_ECP_DP_SECP521R1_ENABLED */
-
-#endif /* MBEDTLS_ECDSA_C */
-
 #if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
-
 #if defined(MBEDTLS_SHA256_C)
         case MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA256:
             *md_alg = MBEDTLS_MD_SHA256;
             *pk_type = MBEDTLS_PK_RSASSA_PSS;
             break;
 #endif /* MBEDTLS_SHA256_C  */
-
 #if defined(MBEDTLS_SHA384_C)
         case MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA384:
             *md_alg = MBEDTLS_MD_SHA384;
             *pk_type = MBEDTLS_PK_RSASSA_PSS;
             break;
 #endif /* MBEDTLS_SHA384_C */
-
 #if defined(MBEDTLS_SHA512_C)
         case MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA512:
             *md_alg = MBEDTLS_MD_SHA512;
             *pk_type = MBEDTLS_PK_RSASSA_PSS;
             break;
 #endif /* MBEDTLS_SHA512_C */
-
 #endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
 
-#if defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
-    defined(MBEDTLS_PKCS1_V15) && \
-    defined(MBEDTLS_RSA_C)
-
-#if defined(MBEDTLS_SHA256_C)
-        case MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA256:
-            *md_alg = MBEDTLS_MD_SHA256;
-            *pk_type = MBEDTLS_PK_RSA;
-            break;
-#endif /* MBEDTLS_SHA256_C */
-
-#if defined(MBEDTLS_SHA384_C)
-        case MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA384:
-            *md_alg = MBEDTLS_MD_SHA384;
-            *pk_type = MBEDTLS_PK_RSA;
-            break;
-#endif /* MBEDTLS_SHA384_C */
-
-#if defined(MBEDTLS_SHA512_C)
-        case MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA512:
-            *md_alg = MBEDTLS_MD_SHA512;
-            *pk_type = MBEDTLS_PK_RSA;
-            break;
-#endif /* MBEDTLS_SHA512_C */
-
-#endif /* MBEDTLS_SSL_PROTO_TLS1_2 &&
-          MBEDTLS_PKCS1_V15 &&
-          MBEDTLS_RSA_C */
-
             default:
                 return( MBEDTLS_ERR_SSL_FEATURE_UNAVAILABLE );
         }
         return( 0 );
 }
 
+#if defined(MBEDTLS_SSL_PROTO_TLS1_3)
 static inline int mbedtls_ssl_tls13_sig_alg_is_supported(
                                                     const uint16_t sig_alg )
 {
-    mbedtls_pk_type_t pk_type;
-    mbedtls_md_type_t md_alg;
-    return( ! mbedtls_ssl_tls13_get_pk_type_and_md_alg_from_sig_alg(
-                                            sig_alg, &pk_type, &md_alg ) );
+    switch( sig_alg )
+    {
+#if defined(MBEDTLS_ECDSA_C)
+#if defined(MBEDTLS_SHA256_C) && defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED)
+        case MBEDTLS_TLS1_3_SIG_ECDSA_SECP256R1_SHA256:
+            break;
+#endif /* MBEDTLS_SHA256_C && MBEDTLS_ECP_DP_SECP256R1_ENABLED */
+#if defined(MBEDTLS_SHA384_C) && defined(MBEDTLS_ECP_DP_SECP384R1_ENABLED)
+        case MBEDTLS_TLS1_3_SIG_ECDSA_SECP384R1_SHA384:
+            break;
+#endif /* MBEDTLS_SHA384_C && MBEDTLS_ECP_DP_SECP384R1_ENABLED */
+#if defined(MBEDTLS_SHA512_C) && defined(MBEDTLS_ECP_DP_SECP521R1_ENABLED)
+        case MBEDTLS_TLS1_3_SIG_ECDSA_SECP521R1_SHA512:
+            break;
+#endif /* MBEDTLS_SHA512_C && MBEDTLS_ECP_DP_SECP521R1_ENABLED */
+#endif /* MBEDTLS_ECDSA_C */
+
+#if defined(MBEDTLS_X509_RSASSA_PSS_SUPPORT)
+#if defined(MBEDTLS_SHA256_C)
+        case MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA256:
+            break;
+#endif /* MBEDTLS_SHA256_C  */
+#if defined(MBEDTLS_SHA384_C)
+        case MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA384:
+            break;
+#endif /* MBEDTLS_SHA384_C */
+#if defined(MBEDTLS_SHA512_C)
+        case MBEDTLS_TLS1_3_SIG_RSA_PSS_RSAE_SHA512:
+            break;
+#endif /* MBEDTLS_SHA512_C */
+#endif /* MBEDTLS_X509_RSASSA_PSS_SUPPORT */
+#if defined(MBEDTLS_PKCS1_V15) && defined(MBEDTLS_RSA_C)
+
+#if defined(MBEDTLS_SHA256_C)
+        case MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA256:
+            break;
+#endif /* MBEDTLS_SHA256_C */
+
+#if defined(MBEDTLS_SHA384_C)
+        case MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA384:
+            break;
+#endif /* MBEDTLS_SHA384_C */
+
+#if defined(MBEDTLS_SHA512_C)
+        case MBEDTLS_TLS1_3_SIG_RSA_PKCS1_SHA512:
+            break;
+#endif /* MBEDTLS_SHA512_C */
+
+#endif /* MBEDTLS_PKCS1_V15 && MBEDTLS_RSA_C */
+
+
+        default:
+            return( 0 );
+    }
+    return( 1 );
 }
 
 #endif /* MBEDTLS_SSL_PROTO_TLS1_3 */