Files
openairinterface5g/openair3/SECU/kdf.c
T
2015-10-06 16:53:42 +00:00

73 lines
2.1 KiB
C

/*******************************************************************************
OpenAirInterface
Copyright(c) 1999 - 2014 Eurecom
OpenAirInterface is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
OpenAirInterface is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with OpenAirInterface.The full GNU General Public License is
included in this distribution in the file called "COPYING". If not,
see <http://www.gnu.org/licenses/>.
Contact Information
OpenAirInterface Admin: openair_admin@eurecom.fr
OpenAirInterface Tech : openair_tech@eurecom.fr
OpenAirInterface Dev : openair4g-devel@lists.eurecom.fr
Address : Eurecom, Compus SophiaTech 450, route des chappes, 06451 Biot, France.
*******************************************************************************/
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <nettle/hmac.h>
#include "security_types.h"
#include "secu_defs.h"
void kdf(const uint8_t *key, uint16_t key_len, uint8_t *s, uint16_t s_len, uint8_t *out,
uint16_t out_len)
{
struct hmac_sha256_ctx ctx;
memset(&ctx, 0, sizeof(ctx));
hmac_sha256_set_key(&ctx, key_len, key);
hmac_sha256_update(&ctx, s_len, s);
hmac_sha256_digest(&ctx, out_len, out);
}
#ifndef NAS_UE
int derive_keNB(const uint8_t kasme[32], const uint32_t nas_count, uint8_t *keNB)
{
uint8_t s[7];
// FC
s[0] = FC_KENB;
// P0 = Uplink NAS count
s[1] = (nas_count & 0xff000000) >> 24;
s[2] = (nas_count & 0x00ff0000) >> 16;
s[3] = (nas_count & 0x0000ff00) >> 8;
s[4] = (nas_count & 0x000000ff);
// Length of NAS count
s[5] = 0x00;
s[6] = 0x04;
kdf(kasme, 32, s, 7, keNB, 32);
return 0;
}
#endif