RSA-PSS - EVP_PKEY RSA-PSS algorithm support
The RSA-PSS EVP_PKEY implementation is a restricted version of the RSA
algorithm which only supports signing, verification and key generation using
PSS padding modes with optional parameter restrictions.
It has associated private key and public key formats.
This algorithm shares several control operations with the
RSA algorithm but with some restrictions described below.
Signing and verification is similar to the RSA algorithm except the
padding mode is always PSS. If the key in use has parameter restrictions then
the corresponding signature parameters are set to the restrictions: for
example, if the key can only be used with digest SHA256, MGF1 SHA256 and
minimum salt length 32 then the digest, MGF1 digest and salt length will be
set to SHA256, SHA256 and 32 respectively.
By default no parameter restrictions are placed on the generated key.
The public key format is documented in RFC4055.
The PKCS#8 private key format used for RSA-PSS keys is similar to
the RSA format except it uses the id-RSASSA-PSS OID and the
parameters field, if present, restricts the key parameters in the same way
as the public key.
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Licensed under the OpenSSL license (the "License"). You
may not use this file except in compliance with the License. You can obtain
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