This document explains how clients built with the COBOL Wrapper can communicate with Natural RPC Servers running under Natural Security and RPC servers running with impersonation. See Impersonation under z/OS (CICS, Batch, IMS) | z/VSE (CICS).

This document assumes that you are familiar with the concepts of Natural Security and impersonation. To communicate with such a server you will need the following components:

• the Generic RPC Services Modules, which are provided to create and get a security token,

• the RPC Communication Area

To authenticate against Natural Security or impersonated RPC server

1. Specify a user ID, password and optional Natural library in the RPC communication area:

   *  Client information :                  bytes 101-300
       10 COMM-USERID.
                 15 COMM-USERID1      PIC X(8).
                 15 COMM-USERID2      PIC X(8).
       10 COMM-PASSWORD               PIC X(8).
       10 COMM-LIBRARY                PIC X(8).
       10 COMM-SECURITY-TOKEN-LENGTH  PIC 9(4) BINARY.
       10 COMM-SECURITY-TOKEN         PIC X(100).
       10 FILLER                      PIC X(66).

2. Create a security token with the function Create Security Token CT provided by the generic RPC services module.

   In the scenarios Micro Focus, Batch, CICS and IMS with the Call Interface:

   • For RPC Communication Area setting Linkage and External:

       MOVE "2000" TO COMM-VERSION.
       MOVE "CT"   TO COMM-FUNCTION.
     * Set user ID and password in RPC Communication Area
       MOVE "NAT-USER"  TO COMM-USERID.
       MOVE "NAT-PWD"   TO COMM-PASSWORD.
     * Additional for Natural Security set library in RPC Communication Area
       MOVE "NAT-LIB"   TO COMM-LIBRARY.
       CALL "COBSRVI" USING ERX-COMMUNICATION-AREA
       ON EXCEPTION
       . . .
       NOT ON EXCEPTION
       . . .
       END-CALL.

   • For RPC Communication Area setting Copybook. Add the following COBOL Statements to the COBINIT copybook:

        MOVE "CT"   TO COMM-FUNCTION.
      * Set user ID and password in RPC Communication Area
        MOVE "NAT-USER"  TO COMM-USERID.
        MOVE "NAT-PWD"   TO COMM-PASSWORD.
      * Additional for Natural Security set library in RPC Communication Area
        MOVE "NAT-LIB"   TO COMM-LIBRARY.
        CALL "COBSRVI" USING ERX-COMMUNICATION-AREA

     See also Using the Generated Copybooks.

   Or:
   In the scenario Using the COBOL Wrapper for CICS with DFHCOMMAREA Calling Convention (z/OS and z/VSE) with the EXEC CICS LINK Interface:

      MOVE "2000" TO COMM-VERSION.
      MOVE "CT"   TO COMM-FUNCTION.
    * Set user ID and password in RPC Communication Area
      MOVE "NAT-USER"  TO COMM-USERID.
      MOVE "NAT-PWD"   TO COMM-PASSWORD.
    * Additional for Natural Security set library in RPC Communication Area
      MOVE "NAT-LIB"   TO COMM-LIBRARY.
      EXEC CICS LINK PROGRAM  ("COBSRVI")
                     RESP     (CICS-RESP1)
                     RESP2    (CICS-RESP2)
                     COMMAREA (ERX-COMMUNICATION-AREA)
                     LENGTH   (LENGTH OF ERX-COMMUNICATION-AREA)
      END-EXEC.
      IF WORKRESP = DFHRESP(NORMAL)
         IF (COMM-RETURN-CODE = 0) THEN
   *       Perform success-handling
         ELSE
   *       Perform error-handling
         END-IF
      ELSE
   *    Perform error-handling
      END-IF.

After successful return from the generic RPC services module, the security fields in the RPC communication area are properly set, so they can be used in subsequent RPC requests to a secure RPC server, such as:

• Natural RPC server running with Natural Security

• RPC server running with impersonation. See Impersonation under z/OS (CICS, Batch, IMS) | z/VSE (CICS).

We strongly recommend using Using SSL/TLS if you send a security token with the COBOL Wrapper to the secure RPC server. See also SSL/TLS Parameters for EntireX Clients and Serversin the Security documentation.