+/**\r
+ Retrieve the common name (CN) string from one X.509 certificate.\r
+\r
+ Return RETURN_UNSUPPORTED to indicate this interface is not supported.\r
+\r
+ @param[in] Cert Pointer to the DER-encoded X509 certificate.\r
+ @param[in] CertSize Size of the X509 certificate in bytes.\r
+ @param[out] CommonName Buffer to contain the retrieved certificate common\r
+ name string. At most CommonNameSize bytes will be\r
+ written and the string will be null terminated. May be\r
+ NULL in order to determine the size buffer needed.\r
+ @param[in,out] CommonNameSize The size in bytes of the CommonName buffer on input,\r
+ and the size of buffer returned CommonName on output.\r
+ If CommonName is NULL then the amount of space needed\r
+ in buffer (including the final null) is returned.\r
+\r
+ @retval RETURN_UNSUPPORTED The operation is not supported.\r
+\r
+**/\r
+RETURN_STATUS\r
+EFIAPI\r
+X509GetCommonName (\r
+ IN CONST UINT8 *Cert,\r
+ IN UINTN CertSize,\r
+ OUT CHAR8 *CommonName, OPTIONAL\r
+ IN OUT UINTN *CommonNameSize\r
+ )\r
+{\r
+ ASSERT (FALSE);\r
+ return RETURN_UNSUPPORTED;\r
+}\r
+\r