NAME

       EVP_KDF-PBKDF2 - The PBKDF2 EVP_KDF implementation

DESCRIPTION

       Support for computing the PBKDF2 password-based KDF through the EVP_KDF API.

       The EVP_KDF-PBKDF2 algorithm implements the PBKDF2 password-based key derivation function, as described
       in SP800-132; it derives a key from a password using a salt and iteration count.

       The output is considered to be a cryptographic key.

   Identity
       "PBKDF2" is the name for this implementation; it can be used with the EVP_KDF_fetch() function.

   Supported parameters
       The supported parameters are:

       "pass" (OSSL_KDF_PARAM_PASSWORD) <octet string>
       "salt" (OSSL_KDF_PARAM_SALT) <octet string>
       "iter" (OSSL_KDF_PARAM_ITER) <unsigned integer>
           This parameter has a default value of 2048.

       "properties" (OSSL_KDF_PARAM_PROPERTIES) <UTF8 string>
       "digest" (OSSL_KDF_PARAM_DIGEST) <UTF8 string>
           These parameters work as described in "PARAMETERS" in EVP_KDF(3).

       "pkcs5" (OSSL_KDF_PARAM_PKCS5) <integer>
           This  parameter  can be used to enable or disable SP800-132 compliance checks.  Setting the mode to 0
           enables the compliance checks.

           The checks performed are:

           - the iteration count is at least 1000.
           - the salt length is at least 128 bits.
           - the derived key length is at least 112 bits.

           The default provider uses a default mode of 1 for backwards compatibility, and the FIPS provider uses
           a default mode of 0.  This option breaks FIPS compliance if it causes the  approved  "fips-indicator"
           to return 0.

       "fips-indicator" (OSSL_KDF_PARAM_FIPS_APPROVED_INDICATOR) <integer>
           This option is used by the OpenSSL FIPS provider.

           A  getter  that  returns 1 if the operation is FIPS approved, or 0 otherwise.  This may be used after
           calling EVP_KDF_derive. It returns 0 if "pkcs5" is set to 1 and the derived key length,  salt  length
           or iteration count test fails.

NOTES

       A  typical  application of this algorithm is to derive keying material for an encryption algorithm from a
       password in the "pass", a salt in "salt", and an iteration count.

       Increasing the "iter" parameter slows down the algorithm which makes it harder for an attacker to perform
       a brute force attack using a large number of candidate passwords.

       No assumption is made regarding the given password; it is simply treated as a byte sequence.

CONFORMING TO

       SP800-132

SEE ALSO

       EVP_KDF(3),  EVP_KDF_CTX_new(3),   EVP_KDF_CTX_free(3),   EVP_KDF_CTX_set_params(3),   EVP_KDF_derive(3),
       "PARAMETERS" in EVP_KDF(3)

HISTORY

       This functionality was added in OpenSSL 3.0.

COPYRIGHT

       Copyright 2018-2024 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>.

3.5.0                                              2025-06-04                               EVP_KDF-PBKDF2(7SSL)