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PKCS12_key_gen_utf8_ex(3)           OpenSSL          PKCS12_key_gen_utf8_ex(3)



NAME
       PKCS12_key_gen_asc, PKCS12_key_gen_asc_ex, PKCS12_key_gen_uni,
       PKCS12_key_gen_uni_ex, PKCS12_key_gen_utf8, PKCS12_key_gen_utf8_ex -
       PKCS#12 Password based key derivation

LIBRARY
       libcrypto, -lcrypto

SYNOPSIS
        #include <openssl/pkcs12.h>

        int PKCS12_key_gen_asc(const char *pass, int passlen, unsigned char *salt,
                               int saltlen, int id, int iter, int n,
                               unsigned char *out, const EVP_MD *md_type);
        int PKCS12_key_gen_asc_ex(const char *pass, int passlen, unsigned char *salt,
                                  int saltlen, int id, int iter, int n,
                                  unsigned char *out, const EVP_MD *md_type,
                                  OSSL_LIB_CTX *ctx, const char *propq);
        int PKCS12_key_gen_uni(unsigned char *pass, int passlen, unsigned char *salt,
                               int saltlen, int id, int iter, int n,
                               unsigned char *out, const EVP_MD *md_type);
        int PKCS12_key_gen_uni_ex(unsigned char *pass, int passlen, unsigned char *salt,
                                  int saltlen, int id, int iter, int n,
                                  unsigned char *out, const EVP_MD *md_type,
                                  OSSL_LIB_CTX *ctx, const char *propq);
        int PKCS12_key_gen_utf8(const char *pass, int passlen, unsigned char *salt,
                                int saltlen, int id, int iter, int n,
                                unsigned char *out, const EVP_MD *md_type);
        int PKCS12_key_gen_utf8_ex(const char *pass, int passlen, unsigned char *salt,
                                   int saltlen, int id, int iter, int n,
                                   unsigned char *out, const EVP_MD *md_type,
                                   OSSL_LIB_CTX *ctx, const char *propq);

DESCRIPTION
       These methods perform a key derivation according to PKCS#12 (RFC7292)
       with an input password pass of length passlen, a salt salt of length
       saltlen, an iteration count iter and a digest algorithm md_type.  The
       ID byte id determines how the resulting key is intended to be used:

       ⊕   If ID=1, then the pseudorandom bits being produced are to be used
           as key material for performing encryption or decryption.

       ⊕   If ID=2, then the pseudorandom bits being produced are to be used
           as an IV (Initial Value) for encryption or decryption.

       ⊕   If ID=3, then the pseudorandom bits being produced are to be used
           as an integrity key for MACing.

       The intended format of the supplied password is determined by the
       method chosen:

       ⊕   PKCS12_key_gen_asc() and PKCS12_key_gen_asc_ex() expect an ASCII-
           formatted password.

       ⊕   PKCS12_key_gen_uni() and PKCS12_key_gen_uni_ex() expect a Unicode-
           formatted password.

       ⊕   PKCS12_key_gen_utf8() and PKCS12_key_gen_utf8_ex() expect a UTF-8
           encoded password.

       pass is the password used in the derivation of length passlen. pass is
       an optional parameter and can be NULL. If passlen is -1, then the
       function will calculate the length of pass using strlen().

       salt is the salt used in the derivation of length saltlen. If the salt
       is NULL, then saltlen must be 0. The function will not attempt to
       calculate the length of the salt because it is not assumed to be NULL
       terminated.

       iter is the iteration count and its value should be greater than or
       equal to 1. RFC 2898 suggests an iteration count of at least 1000. Any
       iter less than 1 is treated as a single iteration.

       digest is the message digest function used in the derivation.

       The derived key will be written to out. The size of the out buffer is
       specified via n.

       Functions ending in _ex() allow for a library context ctx and property
       query propq to be used to select algorithm implementations.

NOTES
       A typical application of this function 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.

RETURN VALUES
       Returns 1 on success or 0 on error.

CONFORMING TO
       IETF RFC 7292 (<https://tools.ietf.org/html/rfc7292>)

SEE ALSO
       PKCS12_create_ex(3), PKCS12_pbe_crypt_ex(3), passphrase-encoding(7)

HISTORY
       PKCS12_key_gen_asc_ex(), PKCS12_key_gen_uni_ex() and
       PKCS12_key_gen_utf8_ex() were added in OpenSSL 3.0.

COPYRIGHT
       Copyright 2021 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>.



3.0.12                            2023-05-07         PKCS12_key_gen_utf8_ex(3)