OT: I would disagree that ICSF is the "overall better choice". IMHO, if you do not need unique Crypto Express co-processor functions or completely and totally secure keys then ICSF is just wasted overhead compared to using the native CPACF instructions.
I have measured the difference between using native CPACF and the ICSF equivalents for "clear key" computations and it is many, many orders of magnitude slower to use ICSF. That is unacceptable. Peter -----Original Message----- From: IBM Mainframe Assembler List [mailto:ASSEMBLER-LIST@LISTSERV.UGA.EDU] On Behalf Of Tony Harminc Sent: Thursday, August 10, 2017 3:36 PM To: ASSEMBLER-LIST@LISTSERV.UGA.EDU Subject: KMx vs PCC crypto instructions The KM[x] (Cipher Message[with xxx]) set of crypto instructions seems to do the same things as PCC (Perform Cryptographic Computation). I haven't checked every option in excruciating detail, but for the common ones (DES, 3DES, AES) there is at least a lot of overlap. For new code, what should I choose, and why? Both seem to support encrypted keys, so that isn't the differentiator. For old code, where I have (say) a DES routine in software that I would like to replace, are the criteria different? (Of course I am aware that perhaps calls to ICSF are the overall better choice, but I would still like to understand the reasons for the existence of these two sets of instructions.) Thanks... Tony H. -- This message and any attachments are intended only for the use of the addressee and may contain information that is privileged and confidential. If the reader of the message is not the intended recipient or an authorized representative of the intended recipient, you are hereby notified that any dissemination of this communication is strictly prohibited. If you have received this communication in error, please notify us immediately by e-mail and delete the message and any attachments from your system.
