Unformatted logon requests using mixed-case passwords

Mixed case passwords can be used by applications if an SAF-compliant security product (such as RACF®) has enabled this support. In some cases, the USS LOGON DATA parameter is used to send the password to the application. If a terminal user enters a mixed case password on the USS LOGON command and it is translated to uppercase by the translation table, the logon will fail if the target application expects to receive the password in mixed case.

The USS LOGON command is displayed on the terminal as it is typed. Therefore, the password is displayed. For additional security, you can inform the terminal user to discontinue entering the password as part of the USS LOGON process. Instead, the application should prompt the terminal user for the password in a non-displayed field. If mixed case passwords are used and the terminal user continues to enter the password as part of the USS LOGON command, the logon will fail when using TRANSLATE=YES (the default) on the USSPARM because the password has been translated to uppercase.

To continue to allow the terminal user to enter the password on the LOGON command, use one of the following methods to support mixed case passwords. With any of these methods, if the user ID is entered with the password, you must first verify whether the application supports translating the user ID to uppercase. A simple test is to enter the DATA portion of the USS LOGON within single quotation marks with the user ID specified in lowercase. USS will not translate data within single quotation marks and the quotation marks are removed before the data is passed to the application. If the logon fails, the application does not support translating the user ID to uppercase and a terminal user must enter the user ID in uppercase and the password in mixed case for the methods suggested.

If the current USS translate table is used to set all characters to uppercase, add the TRANSLATE=NO operand to the USSPARM macro for the corresponding USSCMD to prevent translation of the specified DATA USSPARM containing the password to uppercase. See the z/OS Communications Server: SNA Resource Definition Reference for details.
Because USS will not process data within single quotation marks against the translate table (the quotation marks are removed before the data is passed to the application), instruct terminal users to enter the DATA portion of the USS LOGON within single quotation marks.
If the terminal user is specifying only APPLID and DATA on the USS LOGON command, an interpret table can be used. The interpret function passes all entered data to the application in untranslated format. Use REMOVE=Y on the LOGCHAR macro to remove the first non-blank string from the entered data. An interpret table should be set up to look for both an upper and a lowercase APPLID because the terminal user could enter the APPLID in lowercase.