EVP_ASYM_CIPHER-RSA(7)

EVP_ASYM_CIPHER-RSA(7) | OpenSSL | EVP_ASYM_CIPHER-RSA(7)

# NAME

EVP_ASYM_CIPHER-RSA - RSA Asymmetric Cipher algorithm support

# DESCRIPTION

Asymmetric Cipher support for the RSA key type.

## RSA Asymmetric Cipher parameters

"pad-mode" (OSSL_ASYM_CIPHER_PARAM_PAD_MODE) <UTF8 string>
  The default provider understands these RSA padding modes in string form:

"none" (OSSL_PKEY_RSA_PAD_MODE_NONE)
"oaep" (OSSL_PKEY_RSA_PAD_MODE_OAEP)
"pkcs1" (OSSL_PKEY_RSA_PAD_MODE_PKCSV15)
  This padding mode is no longer supported by the FIPS provider for key agreement and key transport. (This is a FIPS 140-3 requirement). See "OPTIONS" in openssl-fipsinstall(1) -rsa_pkcs15_pad_disabled.
"x931" (OSSL_PKEY_RSA_PAD_MODE_X931)

"pad-mode" (OSSL_ASYM_CIPHER_PARAM_PAD_MODE) <integer>
  The default provider understands these RSA padding modes in integer form:

1 (RSA_PKCS1_PADDING)
  This padding mode is no longer supported by the FIPS provider for key agreement and key transport. (This is a FIPS 140-3 requirement)
3 (RSA_NO_PADDING)
4 (RSA_PKCS1_OAEP_PADDING)
5 (RSA_X931_PADDING)

See EVP_PKEY_CTX_set_rsa_padding(3) for further details.

"digest" (OSSL_ASYM_CIPHER_PARAM_OAEP_DIGEST) <UTF8 string>
"digest-props" (OSSL_ASYM_CIPHER_PARAM_OAEP_DIGEST_PROPS) <UTF8 string>
"mgf1-digest" (OSSL_ASYM_CIPHER_PARAM_MGF1_DIGEST) <UTF8 string>
"mgf1-digest-props" (OSSL_ASYM_CIPHER_PARAM_MGF1_DIGEST_PROPS) <UTF8 string>
"oaep-label" (OSSL_ASYM_CIPHER_PARAM_OAEP_LABEL) <octet string>
"tls-client-version" (OSSL_ASYM_CIPHER_PARAM_TLS_CLIENT_VERSION) <unsigned integer>
  See RSA_PKCS1_WITH_TLS_PADDING on the page EVP_PKEY_CTX_set_rsa_padding(3).
"tls-negotiated-version" (OSSL_ASYM_CIPHER_PARAM_TLS_CLIENT_VERSION) <unsigned integer>
  See RSA_PKCS1_WITH_TLS_PADDING on the page EVP_PKEY_CTX_set_rsa_padding(3).

  See "Asymmetric Cipher Parameters" in provider-asym_cipher(7) for more information.

The OpenSSL FIPS provider also supports the following parameters:

"fips-indicator" (OSSL_ASYM_CIPHER_PARAM_FIPS_APPROVED_INDICATOR) <integer>
"key-check" (OSSL_ASYM_CIPHER_PARAM_FIPS_KEY_CHECK) <integer>
  See "Asymmetric Cipher Parameters" in provider-asym_cipher(7) for more information.
"pkcs15-pad-disabled" (OSSL_ASYM_CIPHER_PARAM_FIPS_RSA_PKCS15_PAD_DISABLED) <integer>
  The default value of 1 causes an error during encryption if the RSA padding mode is set to "pkcs1". Setting this to zero will ignore the error and set the approved "fips-indicator" to 0. This option breaks FIPS compliance if it causes the approved "fips-indicator" to return 0.

# SEE ALSO

EVP_PKEY-RSA(7), EVP_PKEY(3), provider-asym_cipher(7), provider-keymgmt(7), OSSL_PROVIDER-default(7) OSSL_PROVIDER-FIPS(7)

# COPYRIGHT

Copyright 2022-2025 The OpenSSL Project Authors. All Rights Reserved.

Licensed under the Apache License 2.0 (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>.

2026-04-07 | 3.5.6