1=pod 2 3=head1 NAME 4 5PKCS12_key_gen_asc, PKCS12_key_gen_asc_ex, 6PKCS12_key_gen_uni, PKCS12_key_gen_uni_ex, 7PKCS12_key_gen_utf8, PKCS12_key_gen_utf8_ex - PKCS#12 Password based key derivation 8 9=head1 SYNOPSIS 10 11 #include <openssl/pkcs12.h> 12 13 int PKCS12_key_gen_asc(const char *pass, int passlen, unsigned char *salt, 14 int saltlen, int id, int iter, int n, 15 unsigned char *out, const EVP_MD *md_type); 16 int PKCS12_key_gen_asc_ex(const char *pass, int passlen, unsigned char *salt, 17 int saltlen, int id, int iter, int n, 18 unsigned char *out, const EVP_MD *md_type, 19 OSSL_LIB_CTX *ctx, const char *propq); 20 int PKCS12_key_gen_uni(unsigned char *pass, int passlen, unsigned char *salt, 21 int saltlen, int id, int iter, int n, 22 unsigned char *out, const EVP_MD *md_type); 23 int PKCS12_key_gen_uni_ex(unsigned char *pass, int passlen, unsigned char *salt, 24 int saltlen, int id, int iter, int n, 25 unsigned char *out, const EVP_MD *md_type, 26 OSSL_LIB_CTX *ctx, const char *propq); 27 int PKCS12_key_gen_utf8(const char *pass, int passlen, unsigned char *salt, 28 int saltlen, int id, int iter, int n, 29 unsigned char *out, const EVP_MD *md_type); 30 int PKCS12_key_gen_utf8_ex(const char *pass, int passlen, unsigned char *salt, 31 int saltlen, int id, int iter, int n, 32 unsigned char *out, const EVP_MD *md_type, 33 OSSL_LIB_CTX *ctx, const char *propq); 34 35=head1 DESCRIPTION 36 37These methods perform a key derivation according to PKCS#12 (RFC7292) 38with an input password I<pass> of length I<passlen>, a salt I<salt> of length 39I<saltlen>, an iteration count I<iter> and a digest algorithm I<md_type>. 40The ID byte I<id> determines how the resulting key is intended to be used: 41 42=over 4 43 44=item * 45 46If ID=1, then the pseudorandom bits being produced are to be used 47as key material for performing encryption or decryption. 48 49=item * 50 51If ID=2, then the pseudorandom bits being produced are to be used 52as an IV (Initial Value) for encryption or decryption. 53 54=item * 55 56If ID=3, then the pseudorandom bits being produced are to be used 57as an integrity key for MACing. 58 59=back 60 61The intended format of the supplied password is determined by the method chosen: 62 63=over 4 64 65=item * 66 67PKCS12_key_gen_asc() and PKCS12_key_gen_asc_ex() expect an ASCII-formatted password. 68 69=item * 70 71PKCS12_key_gen_uni() and PKCS12_key_gen_uni_ex() expect a Unicode-formatted password. 72 73=item * 74 75PKCS12_key_gen_utf8() and PKCS12_key_gen_utf8_ex() expect a UTF-8 encoded password. 76 77=back 78 79I<pass> is the password used in the derivation of length I<passlen>. I<pass> 80is an optional parameter and can be NULL. If I<passlen> is -1, then the 81function will calculate the length of I<pass> using strlen(). 82 83I<salt> is the salt used in the derivation of length I<saltlen>. If the 84I<salt> is NULL, then I<saltlen> must be 0. The function will not 85attempt to calculate the length of the I<salt> because it is not assumed to 86be NULL terminated. 87 88I<iter> is the iteration count and its value should be greater than or 89equal to 1. RFC 2898 suggests an iteration count of at least 1000. Any 90I<iter> less than 1 is treated as a single iteration. 91 92I<digest> is the message digest function used in the derivation. 93 94The derived key will be written to I<out>. The size of the I<out> buffer 95is specified via I<n>. 96 97Functions ending in _ex() allow for a library context I<ctx> and property query 98I<propq> to be used to select algorithm implementations. 99 100=head1 NOTES 101 102A typical application of this function is to derive keying material for an 103encryption algorithm from a password in the I<pass>, a salt in I<salt>, 104and an iteration count. 105 106Increasing the I<iter> parameter slows down the algorithm which makes it 107harder for an attacker to perform a brute force attack using a large number 108of candidate passwords. 109 110=head1 RETURN VALUES 111 112Returns 1 on success or 0 on error. 113 114=head1 CONFORMING TO 115 116IETF RFC 7292 (L<https://tools.ietf.org/html/rfc7292>) 117 118=head1 SEE ALSO 119 120L<PKCS12_create_ex(3)>, 121L<PKCS12_pbe_crypt_ex(3)>, 122L<passphrase-encoding(7)> 123 124=head1 HISTORY 125 126PKCS12_key_gen_asc_ex(), PKCS12_key_gen_uni_ex() and PKCS12_key_gen_utf8_ex() 127were added in OpenSSL 3.0. 128 129=head1 COPYRIGHT 130 131Copyright 2021 The OpenSSL Project Authors. All Rights Reserved. 132 133Licensed under the Apache License 2.0 (the "License"). You may not use 134this file except in compliance with the License. You can obtain a copy 135in the file LICENSE in the source distribution or at 136L<https://www.openssl.org/source/license.html>. 137 138=cut 139