Communications Bridge Security › Decrypting the CFB

Decrypting the CFB

The CFB data transmitted from DPC applications can optionally be encrypted. A flag byte in the CFB header signifies the data has been encrypted. This flag byte is used to notify the receiver of the CFB that it has been encrypted. It is the responsibility of the receiver to decrypt the CFB prior to using it.

With respect to the Comm. Bridge, the data in the CFB only needs to be decrypted if the security data located in the security offset area is to be used when sending the cooperative flow request to a target server. The Comm. Bridge uses the CFB CMUseSecure CFB flag to determine if the data in the security offset should be used. The CFB CMUseSecure CFB flag is set on by the client runtime if its invocation of the client side security exit returns a TRUE for the bClntMgrSecurity flag.

If the DPC calls for an encrypted CFB, a flag byte signifying the data has been encrypted is placed in the header portion of the CFB. This flag byte is used to notify the receiver of the CFB that encryption has been used. It is then the receiver's responsibility to decrypt the CFB prior to using it.