[jose] RSA-PSS salt size

Mike Jones <Michael.Jones@microsoft.com> Wed, 31 July 2013 14:27 UTC

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From: Mike Jones <Michael.Jones@microsoft.com>
To: "jose@ietf.org" <jose@ietf.org>
Thread-Topic: RSA-PSS salt size
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Date: Wed, 31 Jul 2013 14:26:40 +0000
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Subject: [jose] RSA-PSS salt size
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It was pointed out to me that we failed to specify the salt size for RSA PSS signatures.  RFC 3447 says that "Typical salt lengths in octets are hLen (the length of the output of the hash function Hash) and 0."  Having looked into it a bit I believe that it would be appropriate for us to specify that the salt length be the same as the output size of the hash function used.  So 256 for PS256, 384 for PS384, and 512 for PS512.

Any disagreement with that choice?

                                                            -- Mike