| /* |
| * Copyright (C) 2016 by sysmocom - s.f.m.c. GmbH |
| * |
| * All Rights Reserved |
| * |
| * This program 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 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program 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 this program; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| */ |
| |
| #include <osmocom/core/bits.h> |
| #include <osmocom/crypt/gprs_cipher.h> |
| #include <osmocom/crypt/auth.h> |
| #include <osmocom/gsm/kasumi.h> |
| |
| #include <stdint.h> |
| #include <string.h> |
| |
| /*! \addtogroup gea |
| * @{ |
| * Implementation of GPRS Ciphers GEA3 and GEA4. |
| * \file gea.c */ |
| |
| /*! Performs the GEA4 algorithm as in 3GPP TS 55.226 V9.0.0 |
| * \param[in,out] out Buffer for gamma for encrypted/decrypted |
| * \param[in] len Length of out, in bytes |
| * \param[in] kc Buffer with the ciphering key |
| * \param[in] iv Init vector |
| * \param[in] direct Direction: 0 (MS -> SGSN) or 1 (SGSN -> MS) |
| */ |
| int gea4(uint8_t *out, uint16_t len, uint8_t *kc, uint32_t iv, |
| enum gprs_cipher_direction direction) |
| { |
| _kasumi_kgcore(0xFF, 0, iv, direction, kc, out, len * 8); |
| return 0; |
| } |
| |
| /*! Performs the GEA3 algorithm as in 3GPP TS 55.216 V6.2.0 |
| * \param[in,out] out Buffer for gamma for encrypted/decrypted |
| * \param[in] len Length of out, in bytes |
| * \param[in] kc Buffer with the ciphering key |
| * \param[in] iv Init vector |
| * \param[in] direct Direction: 0 (MS -> SGSN) or 1 (SGSN -> MS) |
| */ |
| int gea3(uint8_t *out, uint16_t len, uint8_t *kc, uint32_t iv, |
| enum gprs_cipher_direction direction) |
| { |
| uint8_t ck[gprs_cipher_key_length(GPRS_ALGO_GEA4)]; |
| osmo_c4(ck, kc); |
| return gea4(out, len, ck, iv, direction); |
| } |
| |
| /*! @} */ |