| lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 1 | =pod |
| 2 | |
| 3 | =head1 NAME |
| 4 | |
| 5 | RSA-PSS - EVP_PKEY RSA-PSS algorithm support |
| 6 | |
| 7 | =head1 DESCRIPTION |
| 8 | |
| 9 | The B<RSA-PSS> EVP_PKEY implementation is a restricted version of the RSA |
| 10 | algorithm which only supports signing, verification and key generation |
| 11 | using PSS padding modes with optional parameter restrictions. |
| 12 | |
| 13 | It has associated private key and public key formats. |
| 14 | |
| 15 | This algorithm shares several control operations with the B<RSA> algorithm |
| 16 | but with some restrictions described below. |
| 17 | |
| 18 | =head2 Signing and Verification |
| 19 | |
| 20 | Signing and verification is similar to the B<RSA> algorithm except the |
| 21 | padding mode is always PSS. If the key in use has parameter restrictions then |
| 22 | the corresponding signature parameters are set to the restrictions: |
| 23 | for example, if the key can only be used with digest SHA256, MGF1 SHA256 |
| 24 | and minimum salt length 32 then the digest, MGF1 digest and salt length |
| 25 | will be set to SHA256, SHA256 and 32 respectively. |
| 26 | |
| 27 | =head2 Key Generation |
| 28 | |
| 29 | By default no parameter restrictions are placed on the generated key. |
| 30 | |
| 31 | =head1 NOTES |
| 32 | |
| 33 | The public key format is documented in RFC4055. |
| 34 | |
| 35 | The PKCS#8 private key format used for RSA-PSS keys is similar to the RSA |
| 36 | format except it uses the B<id-RSASSA-PSS> OID and the parameters field, if |
| 37 | present, restricts the key parameters in the same way as the public key. |
| 38 | |
| 39 | =head1 CONFORMING TO |
| 40 | |
| 41 | RFC 4055 |
| 42 | |
| 43 | =head1 SEE ALSO |
| 44 | |
| 45 | L<EVP_PKEY_CTX_set_rsa_pss_keygen_md(3)>, |
| 46 | L<EVP_PKEY_CTX_set_rsa_pss_keygen_mgf1_md(3)>, |
| 47 | L<EVP_PKEY_CTX_set_rsa_pss_keygen_saltlen(3)>, |
| 48 | L<EVP_PKEY_CTX_new(3)>, |
| 49 | L<EVP_PKEY_CTX_ctrl_str(3)>, |
| 50 | L<EVP_PKEY_derive(3)> |
| 51 | |
| 52 | =head1 COPYRIGHT |
| 53 | |
| 54 | Copyright 2017-2018 The OpenSSL Project Authors. All Rights Reserved. |
| 55 | |
| 56 | Licensed under the OpenSSL license (the "License"). You may not use |
| 57 | this file except in compliance with the License. You can obtain a copy |
| 58 | in the file LICENSE in the source distribution or at |
| 59 | L<https://www.openssl.org/source/license.html>. |
| 60 | |
| 61 | =cut |