/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* lib/crypto/krb/prf.c */
/*
* Copyright (C) 2004 by the Massachusetts Institute of Technology.
* All rights reserved.
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
* M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*/
/*
* This contains the implementation of krb5_c_prf, which will find the
* enctype-specific PRF and then generate pseudo-random data. This function
* yields krb5_c_prf_length bytes of output.
*/
#include "crypto_int.h"
krb5_error_code KRB5_CALLCONV
krb5_c_prf_length(krb5_context context, krb5_enctype enctype, size_t *len)
{
const struct krb5_keytypes *ktp;
assert(len);
ktp = find_enctype(enctype);
if (ktp == NULL)
return KRB5_BAD_ENCTYPE;
*len = ktp->prf_length;
return 0;
}
krb5_error_code KRB5_CALLCONV
krb5_k_prf(krb5_context context, krb5_key key,
krb5_data *input, krb5_data *output)
{
const struct krb5_keytypes *ktp;
krb5_error_code ret;
assert(input && output);
assert(output->data);
ktp = find_enctype(key->keyblock.enctype);
if (ktp == NULL)
return KRB5_BAD_ENCTYPE;
if (ktp->prf == NULL)
return KRB5_CRYPTO_INTERNAL;
output->magic = KV5M_DATA;
if (ktp->prf_length != output->length)
return KRB5_CRYPTO_INTERNAL;
ret = ktp->prf(ktp, key, input, output);
return ret;
}
krb5_error_code KRB5_CALLCONV
krb5_c_prf(krb5_context context, const krb5_keyblock *keyblock,
krb5_data *input, krb5_data *output)
{
krb5_key key;
krb5_error_code ret;
ret = krb5_k_create_key(context, keyblock, &key);
if (ret != 0)
return ret;
ret = krb5_k_prf(context, key, input, output);
krb5_k_free_key(context, key);
return ret;
}