1=pod 2 3=head1 NAME 4 5EVP_KDF-PBKDF2 - The PBKDF2 EVP_KDF implementation 6 7=head1 DESCRIPTION 8 9Support for computing the B<PBKDF2> password-based KDF through the B<EVP_KDF> 10API. 11 12The EVP_KDF-PBKDF2 algorithm implements the PBKDF2 password-based key 13derivation function, as described in SP800-132; it derives a key from a password 14using a salt and iteration count. 15 16The output is considered to be a cryptographic key. 17 18=head2 Identity 19 20"PBKDF2" is the name for this implementation; it 21can be used with the EVP_KDF_fetch() function. 22 23=head2 Supported parameters 24 25The supported parameters are: 26 27=over 4 28 29=item "pass" (B<OSSL_KDF_PARAM_PASSWORD>) <octet string> 30 31=item "salt" (B<OSSL_KDF_PARAM_SALT>) <octet string> 32 33=item "iter" (B<OSSL_KDF_PARAM_ITER>) <unsigned integer> 34 35This parameter has a default value of 2048. 36 37=item "properties" (B<OSSL_KDF_PARAM_PROPERTIES>) <UTF8 string> 38 39=item "digest" (B<OSSL_KDF_PARAM_DIGEST>) <UTF8 string> 40 41These parameters work as described in L<EVP_KDF(3)/PARAMETERS>. 42 43=item "pkcs5" (B<OSSL_KDF_PARAM_PKCS5>) <integer> 44 45This parameter can be used to enable or disable SP800-132 compliance checks. 46Setting the mode to 0 enables the compliance checks. 47 48The checks performed are: 49 50=over 4 51 52=item - the iteration count is at least 1000. 53 54=item - the salt length is at least 128 bits. 55 56=item - the derived key length is at least 112 bits. 57 58=back 59 60The default provider uses a default mode of 1 for backwards compatibility, 61and the FIPS provider uses a default mode of 0. 62 63The value string is expected to be a decimal number 0 or 1. 64 65=back 66 67=head1 NOTES 68 69A typical application of this algorithm is to derive keying material for an 70encryption algorithm from a password in the "pass", a salt in "salt", 71and an iteration count. 72 73Increasing the "iter" parameter slows down the algorithm which makes it 74harder for an attacker to perform a brute force attack using a large number 75of candidate passwords. 76 77No assumption is made regarding the given password; it is simply treated as a 78byte sequence. 79 80=head1 CONFORMING TO 81 82SP800-132 83 84=head1 SEE ALSO 85 86L<EVP_KDF(3)>, 87L<EVP_KDF_CTX_new(3)>, 88L<EVP_KDF_CTX_free(3)>, 89L<EVP_KDF_CTX_set_params(3)>, 90L<EVP_KDF_derive(3)>, 91L<EVP_KDF(3)/PARAMETERS> 92 93=head1 HISTORY 94 95This functionality was added in OpenSSL 3.0. 96 97=head1 COPYRIGHT 98 99Copyright 2018-2022 The OpenSSL Project Authors. All Rights Reserved. 100 101Licensed under the Apache License 2.0 (the "License"). You may not use 102this file except in compliance with the License. You can obtain a copy 103in the file LICENSE in the source distribution or at 104L<https://www.openssl.org/source/license.html>. 105 106=cut 107