| | 1 | /***************************************************************************** |
| | 2 | * WARNING |
| | 3 | * |
| | 4 | * THIS CODE IS CREATED FOR EXPERIMENTATION AND EDUCATIONAL USE ONLY. |
| | 5 | * |
| | 6 | * USAGE OF THIS CODE IN OTHER WAYS MAY INFRINGE UPON THE INTELLECTUAL |
| | 7 | * PROPERTY OF OTHER PARTIES, SUCH AS INSIDE SECURE AND HID GLOBAL, |
| | 8 | * AND MAY EXPOSE YOU TO AN INFRINGEMENT ACTION FROM THOSE PARTIES. |
| | 9 | * |
| | 10 | * THIS CODE SHOULD NEVER BE USED TO INFRINGE PATENTS OR INTELLECTUAL PROPERTY RIGHTS. |
| | 11 | * |
| | 12 | ***************************************************************************** |
| | 13 | * |
| | 14 | * This file is part of loclass. It is a reconstructon of the cipher engine |
| | 15 | * used in iClass, and RFID techology. |
| | 16 | * |
| | 17 | * The implementation is based on the work performed by |
| | 18 | * Flavio D. Garcia, Gerhard de Koning Gans, Roel Verdult and |
| | 19 | * Milosch Meriac in the paper "Dismantling IClass". |
| | 20 | * |
| | 21 | * Copyright (C) 2014 Martin Holst Swende |
| | 22 | * |
| | 23 | * This is free software: you can redistribute it and/or modify |
| | 24 | * it under the terms of the GNU General Public License version 2 as published |
| | 25 | * by the Free Software Foundation, or, at your option, any later version. |
| | 26 | * |
| | 27 | * This file is distributed in the hope that it will be useful, |
| | 28 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| | 29 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| | 30 | * GNU General Public License for more details. |
| | 31 | * |
| | 32 | * You should have received a copy of the GNU General Public License |
| | 33 | * along with loclass. If not, see <http://www.gnu.org/licenses/>. |
| | 34 | * |
| | 35 | * |
| | 36 | ****************************************************************************/ |
| | 37 | |
| | 38 | #ifndef OPTIMIZED_CIPHER_H |
| | 39 | #define OPTIMIZED_CIPHER_H |
| | 40 | #include <stdint.h> |
| | 41 | |
| | 42 | /** |
| | 43 | * Definition 1 (Cipher state). A cipher state of iClass s is an element of F 40/2 |
| | 44 | * consisting of the following four components: |
| | 45 | * 1. the left register l = (l 0 . . . l 7 ) ∈ F 8/2 ; |
| | 46 | * 2. the right register r = (r 0 . . . r 7 ) ∈ F 8/2 ; |
| | 47 | * 3. the top register t = (t 0 . . . t 15 ) ∈ F 16/2 . |
| | 48 | * 4. the bottom register b = (b 0 . . . b 7 ) ∈ F 8/2 . |
| | 49 | **/ |
| | 50 | typedef struct { |
| | 51 | uint8_t l; |
| | 52 | uint8_t r; |
| | 53 | uint8_t b; |
| | 54 | uint16_t t; |
| | 55 | } State; |
| | 56 | |
| | 57 | /** The reader MAC is MAC(key, CC * NR ) |
| | 58 | **/ |
| | 59 | void opt_doReaderMAC(uint8_t *cc_nr_p, uint8_t *div_key_p, uint8_t mac[4]); |
| | 60 | /** |
| | 61 | * The tag MAC is MAC(key, CC * NR * 32x0)) |
| | 62 | */ |
| | 63 | void opt_doTagMAC(uint8_t *cc_p, const uint8_t *div_key_p, uint8_t mac[4]); |
| | 64 | |
| | 65 | /** |
| | 66 | * The tag MAC can be divided (both can, but no point in dividing the reader mac) into |
| | 67 | * two functions, since the first 8 bytes are known, we can pre-calculate the state |
| | 68 | * reached after feeding CC to the cipher. |
| | 69 | * @param cc_p |
| | 70 | * @param div_key_p |
| | 71 | * @return the cipher state |
| | 72 | */ |
| | 73 | State opt_doTagMAC_1(uint8_t *cc_p, const uint8_t *div_key_p); |
| | 74 | /** |
| | 75 | * The second part of the tag MAC calculation, since the CC is already calculated into the state, |
| | 76 | * this function is fed only the NR, and internally feeds the remaining 32 0-bits to generate the tag |
| | 77 | * MAC response. |
| | 78 | * @param _init - precalculated cipher state |
| | 79 | * @param nr - the reader challenge |
| | 80 | * @param mac - where to store the MAC |
| | 81 | * @param div_key_p - the key to use |
| | 82 | */ |
| | 83 | void opt_doTagMAC_2(State _init, uint8_t* nr, uint8_t mac[4], const uint8_t* div_key_p); |
| | 84 | |
| | 85 | #endif // OPTIMIZED_CIPHER_H |
projects / proxmark3-svn / blame_incremental