Just to provide some closure on this, Matt and I continued the investigation 
offline.

We did confirm that he has the crypto enabling microcode (FC #3863) installed.

And we found in IBM's Announcement Letter for the z196, 110-170:

"CP Assist for Cryptographic Function (CPACF) enhancements
The following are exploitation of Message-Security-Assist Extension 4:
New instructions:
. Cipher Message with CFB (KMF)
. Cipher Message with Counter (KMCTR)
. Cipher Message with OFB (KMO)
New function codes for existing instructions:
. Compute intermediate Message Digest (KIMD) adds KIMD, an extension for GHASH
More information on CPACF can be found in "IBM System z10 - Delivering security 
rich offerings to protect your data," Hardware Announcement 109-678, dated 
October 20, 2009.
This Crypto function is exclusive to z196."

I don't always trust announcement letters but our conclusion was that the z10 
does not support the new instructions that are available with MSA-4, and the 
vendor confirmed that the MSA-4 support is a pre-req for the CFB support.

Greg Boyd
Mainframe Crypto
www.mainframecrypto.com

On Tue, 29 Sep 2015 14:00:52 -0500, Greg Boyd <[email protected]> 
wrote:

>As I mentioned in the last post, TechDoc Flash10716 does talk about cipher 
>block chaining support on the CEX3 and I'm pretty sure that support is 
>available when the CEX3 is installed on z10.  But I'm not so sure that the 
>chaining support that is avaliable on the CPACF hardware on the z196/z114 was 
>retrofitted to the z10.  So in fact it may not be available on your machine.  
>Additional research is required.  Does the vendor product claim to support CFB 
>mode on a z10?  Do they call out a specific microcode level?
>
>As Rob Schramm points out, you can start ICSF even if you don't have crypto 
>cards, but if the product does not use the APIs that wouldn't provide any 
>benefit. It is possible the vendor product could query the configuration and 
>provide software routines that use the most efficient resources available.  
>That is, the logic could query the config and if the CFB support is not 
>available in the hardware, it could invoke the ICSF APIs that would perform 
>CFB.  And in your case, since the APIs aren't available it might fall back on 
>it's own software routines that do provide CFB support.  If this is true, then 
>starting ICSF might help.  And you would not need an exit to provide the CFB 
>support.  (I would not 
>advocate using an ICSF exit to support CFB.)
>
>I'm also wondering if they are using System SSL APIs? Does the vendor product 
>specifically say that they are using the native instructions that are 
>available on the CPACF hardware?  System SSL is very efficient and will query 
>the environment to determine how best to service the request and as described 
>above will often provide software routines if the appropriate hardware support 
>or if ICSF is not available.
>
>It would be helpful to know which vendor product you are working with.  If 
>you'd like to take this up offline, we can summarize the results for the list 
>later.  Feel free to send me a note.
>
>Greg Boyd
>Mainframe Crypto
>www.mainframecrypto.com
>
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