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EVP_PKEY_CTX_SET_SCRYPT_N(3ossl) OpenSSL EVP_PKEY_CTX_SET_SCRYPT_N(3ossl)
NAME
EVP_PKEY_CTX_set1_scrypt_salt, EVP_PKEY_CTX_set_scrypt_N,
EVP_PKEY_CTX_set_scrypt_r, EVP_PKEY_CTX_set_scrypt_p,
EVP_PKEY_CTX_set_scrypt_maxmem_bytes - EVP_PKEY scrypt KDF support
functions
SYNOPSIS
#include <openssl/kdf.h>
int EVP_PKEY_CTX_set1_scrypt_salt(EVP_PKEY_CTX *pctx, unsigned char *salt,
int saltlen);
int EVP_PKEY_CTX_set_scrypt_N(EVP_PKEY_CTX *pctx, uint64_t N);
int EVP_PKEY_CTX_set_scrypt_r(EVP_PKEY_CTX *pctx, uint64_t r);
int EVP_PKEY_CTX_set_scrypt_p(EVP_PKEY_CTX *pctx, uint64_t p);
int EVP_PKEY_CTX_set_scrypt_maxmem_bytes(EVP_PKEY_CTX *pctx,
uint64_t maxmem);
DESCRIPTION
These functions are used to set up the necessary data to use the scrypt
KDF. For more information on scrypt, see EVP_KDF-SCRYPT(7).
EVP_PKEY_CTX_set1_scrypt_salt() sets the saltlen bytes long salt value.
EVP_PKEY_CTX_set_scrypt_N(), EVP_PKEY_CTX_set_scrypt_r() and
EVP_PKEY_CTX_set_scrypt_p() configure the work factors N, r and p.
EVP_PKEY_CTX_set_scrypt_maxmem_bytes() sets how much RAM key derivation
may maximally use, given in bytes. If RAM is exceeded because the load
factors are chosen too high, the key derivation will fail.
STRING CTRLS
scrypt also supports string based control operations via
EVP_PKEY_CTX_ctrl_str(3). Similarly, the salt can either be specified
using the type parameter "salt" or in hex encoding by using the
"hexsalt" parameter. The work factors N, r and p as well as
maxmem_bytes can be set by using the parameters "N", "r", "p" and
"maxmem_bytes", respectively.
NOTES
There is a newer generic API for KDFs, EVP_KDF(3), which is preferred
over the EVP_PKEY method.
The scrypt KDF also uses EVP_PKEY_CTX_set1_pbe_pass() as well as the
value from the string controls "pass" and "hexpass". See
EVP_PKEY_CTX_set1_pbe_pass(3).
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
COPYRIGHT
Copyright 2017-2020 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>.
3.0.11 2023-09-19 EVP_PKEY_CTX_SET_SCRYPT_N(3ossl)