EVP_PKEY_CTX_SET_RSA_PSS_KEYGEN_MD(3OpenSEVP_PKEY_CTX_SET_RSA_PSS_KEYGEN_MD(3)
NAME
EVP_PKEY_CTX_set_rsa_pss_keygen_md,
EVP_PKEY_CTX_set_rsa_pss_keygen_mgf1_md,
EVP_PKEY_CTX_set_rsa_pss_keygen_saltlen - EVP_PKEY RSA-PSS algorithm
support functions
SYNOPSIS
#include <openssl/rsa.h>
int EVP_PKEY_CTX_set_rsa_pss_keygen_md(EVP_PKEY_CTX *pctx,
const EVP_MD *md);
int EVP_PKEY_CTX_set_rsa_pss_keygen_mgf1_md(EVP_PKEY_CTX *pctx,
const EVP_MD *md);
int EVP_PKEY_CTX_set_rsa_pss_keygen_saltlen(EVP_PKEY_CTX *pctx,
int saltlen);
DESCRIPTION
These are the functions that implement RSA-PSS(7).
Signing and Verification
The macro EVP_PKEY_CTX_set_rsa_padding() is supported but an error is
returned if an attempt is made to set the padding mode to anything
other than PSS. It is otherwise similar to the RSA version.
The EVP_PKEY_CTX_set_rsa_pss_saltlen() macro is used to set the salt
length. If the key has usage restrictions then an error is returned if
an attempt is made to set the salt length below the minimum value. It
is otherwise similar to the RSA operation except detection of the salt
length (using RSA_PSS_SALTLEN_AUTO) is not supported for verification
if the key has usage restrictions.
The EVP_PKEY_CTX_set_signature_md() and EVP_PKEY_CTX_set_rsa_mgf1_md()
macros are used to set the digest and MGF1 algorithms respectively. If
the key has usage restrictions then an error is returned if an attempt
is made to set the digest to anything other than the restricted value.
Otherwise these are similar to the RSA versions.
Key Generation
As with RSA key generation the EVP_PKEY_CTX_set_rsa_keygen_bits() and
EVP_PKEY_CTX_set_rsa_keygen_pubexp() macros are supported for RSA-PSS:
they have exactly the same meaning as for the RSA algorithm.
Optional parameter restrictions can be specified when generating a PSS
key. If any restrictions are set (using the macros described below)
then all parameters are restricted. For example, setting a minimum salt
length also restricts the digest and MGF1 algorithms. If any
restrictions are in place then they are reflected in the corresponding
parameters of the public key when (for example) a certificate request
is signed.
EVP_PKEY_CTX_set_rsa_pss_keygen_md() restricts the digest algorithm the
generated key can use to md.
EVP_PKEY_CTX_set_rsa_pss_keygen_mgf1_md() restricts the MGF1 algorithm
the generated key can use to md.
EVP_PKEY_CTX_set_rsa_pss_keygen_saltlen() restricts the minimum salt
length to saltlen.
NOTES
A context for the RSA-PSS algorithm can be obtained by calling:
EVP_PKEY_CTX *pctx = EVP_PKEY_CTX_new_id(EVP_PKEY_RSA_PSS, NULL);
RETURN VALUES
All these functions return 1 for success and 0 or a negative value for
failure. In particular a return value of -2 indicates the operation is
not supported by the public key algorithm.
SEE ALSO
RSA-PSS(7), EVP_PKEY_CTX_new(3), EVP_PKEY_CTX_ctrl_str(3),
EVP_PKEY_derive(3)
COPYRIGHT
Copyright 2017-2018 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the OpenSSL license (the "License"). You may not use
this file except in compliance with the License. You can obtain a copy
in the file LICENSE in the source distribution or at
<https://www.openssl.org/source/license.html>.
1.1.1k 2021-03EVP_PKEY_CTX_SET_RSA_PSS_KEYGEN_MD(3)