| 1 | /*- |
| 2 | * Copyright (C) 2010, Romain Tartiere. |
| 3 | * |
| 4 | * This program is free software: you can redistribute it and/or modify it |
| 5 | * under the terms of the GNU Lesser General Public License as published by the |
| 6 | * Free Software Foundation, either version 3 of the License, or (at your |
| 7 | * option) any later version. |
| 8 | * |
| 9 | * This program is distributed in the hope that it will be useful, but WITHOUT |
| 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| 12 | * more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU Lesser General Public License |
| 15 | * along with this program. If not, see <http://www.gnu.org/licenses/> |
| 16 | * |
| 17 | * $Id$ |
| 18 | */ |
| 19 | #include <stdlib.h> |
| 20 | #include "desfire_key.h" |
| 21 | |
| 22 | static inline void update_key_schedules (desfirekey_t key); |
| 23 | |
| 24 | static inline void update_key_schedules (desfirekey_t key) { |
| 25 | // DES_set_key ((DES_cblock *)key->data, &(key->ks1)); |
| 26 | // DES_set_key ((DES_cblock *)(key->data + 8), &(key->ks2)); |
| 27 | // if (T_3K3DES == key->type) { |
| 28 | // DES_set_key ((DES_cblock *)(key->data + 16), &(key->ks3)); |
| 29 | // } |
| 30 | } |
| 31 | |
| 32 | void Desfire_des_key_new (const uint8_t value[8], desfirekey_t key) { |
| 33 | uint8_t data[8]; |
| 34 | memcpy (data, value, 8); |
| 35 | for (int n=0; n < 8; n++) |
| 36 | data[n] &= 0xfe; |
| 37 | Desfire_des_key_new_with_version (data, key); |
| 38 | } |
| 39 | |
| 40 | void Desfire_des_key_new_with_version (const uint8_t value[8], desfirekey_t key) { |
| 41 | if ( key != NULL) { |
| 42 | key->type = T_DES; |
| 43 | memcpy (key->data, value, 8); |
| 44 | memcpy (key->data+8, value, 8); |
| 45 | update_key_schedules (key); |
| 46 | } |
| 47 | } |
| 48 | |
| 49 | void Desfire_3des_key_new (const uint8_t value[16], desfirekey_t key) { |
| 50 | uint8_t data[16]; |
| 51 | memcpy (data, value, 16); |
| 52 | for (int n=0; n < 8; n++) |
| 53 | data[n] &= 0xfe; |
| 54 | for (int n=8; n < 16; n++) |
| 55 | data[n] |= 0x01; |
| 56 | Desfire_3des_key_new_with_version (data, key); |
| 57 | } |
| 58 | |
| 59 | void Desfire_3des_key_new_with_version (const uint8_t value[16], desfirekey_t key) { |
| 60 | if ( key != NULL ){ |
| 61 | key->type = T_3DES; |
| 62 | memcpy (key->data, value, 16); |
| 63 | memcpy (key->data + 16, value, 8); |
| 64 | update_key_schedules (key); |
| 65 | } |
| 66 | } |
| 67 | |
| 68 | void Desfire_3k3des_key_new (const uint8_t value[24], desfirekey_t key) { |
| 69 | uint8_t data[24]; |
| 70 | memcpy (data, value, 24); |
| 71 | for (int n=0; n < 8; n++) |
| 72 | data[n] &= 0xfe; |
| 73 | Desfire_3k3des_key_new_with_version (data, key); |
| 74 | } |
| 75 | |
| 76 | void Desfire_3k3des_key_new_with_version (const uint8_t value[24], desfirekey_t key) { |
| 77 | if ( key != NULL){ |
| 78 | key->type = T_3K3DES; |
| 79 | memcpy (key->data, value, 24); |
| 80 | update_key_schedules (key); |
| 81 | } |
| 82 | } |
| 83 | |
| 84 | void Desfire_aes_key_new (const uint8_t value[16], desfirekey_t key) { |
| 85 | Desfire_aes_key_new_with_version (value, 0, key); |
| 86 | } |
| 87 | |
| 88 | void Desfire_aes_key_new_with_version (const uint8_t value[16], uint8_t version, desfirekey_t key) { |
| 89 | |
| 90 | if (key != NULL) { |
| 91 | memcpy (key->data, value, 16); |
| 92 | key->type = T_AES; |
| 93 | key->aes_version = version; |
| 94 | } |
| 95 | } |
| 96 | |
| 97 | uint8_t Desfire_key_get_version (desfirekey_t key) { |
| 98 | uint8_t version = 0; |
| 99 | |
| 100 | for (int n = 0; n < 8; n++) { |
| 101 | version |= ((key->data[n] & 1) << (7 - n)); |
| 102 | } |
| 103 | return version; |
| 104 | } |
| 105 | |
| 106 | void Desfire_key_set_version (desfirekey_t key, uint8_t version) |
| 107 | { |
| 108 | for (int n = 0; n < 8; n++) { |
| 109 | uint8_t version_bit = ((version & (1 << (7-n))) >> (7-n)); |
| 110 | key->data[n] &= 0xfe; |
| 111 | key->data[n] |= version_bit; |
| 112 | if (key->type == T_DES) { |
| 113 | key->data[n+8] = key->data[n]; |
| 114 | } else { |
| 115 | // Write ~version to avoid turning a 3DES key into a DES key |
| 116 | key->data[n+8] &= 0xfe; |
| 117 | key->data[n+8] |= ~version_bit; |
| 118 | } |
| 119 | } |
| 120 | } |
| 121 | |
| 122 | void Desfire_session_key_new (const uint8_t rnda[], const uint8_t rndb[], desfirekey_t authkey, desfirekey_t key) { |
| 123 | |
| 124 | uint8_t buffer[24]; |
| 125 | |
| 126 | switch (authkey->type) { |
| 127 | case T_DES: |
| 128 | memcpy (buffer, rnda, 4); |
| 129 | memcpy (buffer+4, rndb, 4); |
| 130 | Desfire_des_key_new_with_version (buffer, key); |
| 131 | break; |
| 132 | case T_3DES: |
| 133 | memcpy (buffer, rnda, 4); |
| 134 | memcpy (buffer+4, rndb, 4); |
| 135 | memcpy (buffer+8, rnda+4, 4); |
| 136 | memcpy (buffer+12, rndb+4, 4); |
| 137 | Desfire_3des_key_new_with_version (buffer, key); |
| 138 | break; |
| 139 | case T_3K3DES: |
| 140 | memcpy (buffer, rnda, 4); |
| 141 | memcpy (buffer+4, rndb, 4); |
| 142 | memcpy (buffer+8, rnda+6, 4); |
| 143 | memcpy (buffer+12, rndb+6, 4); |
| 144 | memcpy (buffer+16, rnda+12, 4); |
| 145 | memcpy (buffer+20, rndb+12, 4); |
| 146 | Desfire_3k3des_key_new (buffer, key); |
| 147 | break; |
| 148 | case T_AES: |
| 149 | memcpy (buffer, rnda, 4); |
| 150 | memcpy (buffer+4, rndb, 4); |
| 151 | memcpy (buffer+8, rnda+12, 4); |
| 152 | memcpy (buffer+12, rndb+12, 4); |
| 153 | Desfire_aes_key_new (buffer, key); |
| 154 | break; |
| 155 | } |
| 156 | } |