git.zerfleddert.de Git - proxmark3-svn/blob - tools/mfkey/crypto1.c

   1 /*  crypto1.c
   2
   3     This program is free software; you can redistribute it and/or
   4     modify it under the terms of the GNU General Public License
   5     as published by the Free Software Foundation; either version 2
   6     of the License, or (at your option) any later version.
   7
   8     This program is distributed in the hope that it will be useful,
   9     but WITHOUT ANY WARRANTY; without even the implied warranty of
  10     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11     GNU General Public License for more details.
  12
  13     You should have received a copy of the GNU General Public License
  14     along with this program; if not, write to the Free Software
  15     Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  16     MA  02110-1301, US
  17
  18     Copyright (C) 2008-2008 bla <blapost@gmail.com>
  19 */
  20 #include "crapto1.h"
  21 #include <stdlib.h>
  22
  23 struct Crypto1State * crypto1_create(uint64_t key)
  24 {
  25         struct Crypto1State *s = malloc(sizeof(*s));
  26         int i;
  27
  28         for(i = 47;s && i > 0; i -= 2) {
  29                 s->odd  = s->odd  << 1 | BIT(key, (i - 1) ^ 7);
  30                 s->even = s->even << 1 | BIT(key, i ^ 7);
  31         }
  32         return s;
  33 }
  34 void crypto1_destroy(struct Crypto1State *state)
  35 {
  36         free(state);
  37 }
  38 void crypto1_get_lfsr(struct Crypto1State *state, uint64_t *lfsr)
  39 {
  40         int i;
  41         for(*lfsr = 0, i = 23; i >= 0; --i) {
  42                 *lfsr = *lfsr << 1 | BIT(state->odd, i ^ 3);
  43                 *lfsr = *lfsr << 1 | BIT(state->even, i ^ 3);
  44         }
  45 }
  46 uint8_t crypto1_bit(struct Crypto1State *s, uint8_t in, int is_encrypted)
  47 {
  48         uint32_t feedin;
  49         uint32_t tmp;
  50         uint8_t ret = filter(s->odd);
  51
  52         feedin  = ret & !!is_encrypted;
  53         feedin ^= !!in;
  54         feedin ^= LF_POLY_ODD & s->odd;
  55         feedin ^= LF_POLY_EVEN & s->even;
  56         s->even = s->even << 1 | parity(feedin);
  57
  58         tmp = s->odd;
  59         s->odd = s->even;
  60         s->even = tmp;
  61
  62         return ret;
  63 }
  64 uint8_t crypto1_byte(struct Crypto1State *s, uint8_t in, int is_encrypted)
  65 {
  66         /*
  67         uint8_t i, ret = 0;
  68
  69         for (i = 0; i < 8; ++i)
  70                 ret |= crypto1_bit(s, BIT(in, i), is_encrypted) << i;
  71         */
  72         // unfold loop
  73         uint8_t ret = 0;
  74         ret |= crypto1_bit(s, BIT(in, 0), is_encrypted) << 0;
  75         ret |= crypto1_bit(s, BIT(in, 1), is_encrypted) << 1;
  76         ret |= crypto1_bit(s, BIT(in, 2), is_encrypted) << 2;
  77         ret |= crypto1_bit(s, BIT(in, 3), is_encrypted) << 3;
  78         ret |= crypto1_bit(s, BIT(in, 4), is_encrypted) << 4;
  79         ret |= crypto1_bit(s, BIT(in, 5), is_encrypted) << 5;
  80         ret |= crypto1_bit(s, BIT(in, 6), is_encrypted) << 6;
  81         ret |= crypto1_bit(s, BIT(in, 7), is_encrypted) << 7;
  82         return ret;
  83 }
  84 uint32_t crypto1_word(struct Crypto1State *s, uint32_t in, int is_encrypted)
  85 {
  86         /*
  87         uint32_t i, ret = 0;
  88
  89         for (i = 0; i < 32; ++i)
  90                 ret |= crypto1_bit(s, BEBIT(in, i), is_encrypted) << (i ^ 24);
  91 */
  92         uint32_t ret = 0;
  93         ret |= crypto1_bit(s, BEBIT(in, 0), is_encrypted) << (0 ^ 24);
  94         ret |= crypto1_bit(s, BEBIT(in, 1), is_encrypted) << (1 ^ 24);
  95         ret |= crypto1_bit(s, BEBIT(in, 2), is_encrypted) << (2 ^ 24);
  96         ret |= crypto1_bit(s, BEBIT(in, 3), is_encrypted) << (3 ^ 24);
  97         ret |= crypto1_bit(s, BEBIT(in, 4), is_encrypted) << (4 ^ 24);
  98         ret |= crypto1_bit(s, BEBIT(in, 5), is_encrypted) << (5 ^ 24);
  99         ret |= crypto1_bit(s, BEBIT(in, 6), is_encrypted) << (6 ^ 24);
 100         ret |= crypto1_bit(s, BEBIT(in, 7), is_encrypted) << (7 ^ 24);
 101
 102         ret |= crypto1_bit(s, BEBIT(in, 8), is_encrypted) << (8 ^ 24);
 103         ret |= crypto1_bit(s, BEBIT(in, 9), is_encrypted) << (9 ^ 24);
 104         ret |= crypto1_bit(s, BEBIT(in, 10), is_encrypted) << (10 ^ 24);
 105         ret |= crypto1_bit(s, BEBIT(in, 11), is_encrypted) << (11 ^ 24);
 106         ret |= crypto1_bit(s, BEBIT(in, 12), is_encrypted) << (12 ^ 24);
 107         ret |= crypto1_bit(s, BEBIT(in, 13), is_encrypted) << (13 ^ 24);
 108         ret |= crypto1_bit(s, BEBIT(in, 14), is_encrypted) << (14 ^ 24);
 109         ret |= crypto1_bit(s, BEBIT(in, 15), is_encrypted) << (15 ^ 24);
 110
 111         ret |= crypto1_bit(s, BEBIT(in, 16), is_encrypted) << (16 ^ 24);
 112         ret |= crypto1_bit(s, BEBIT(in, 17), is_encrypted) << (17 ^ 24);
 113         ret |= crypto1_bit(s, BEBIT(in, 18), is_encrypted) << (18 ^ 24);
 114         ret |= crypto1_bit(s, BEBIT(in, 19), is_encrypted) << (19 ^ 24);
 115         ret |= crypto1_bit(s, BEBIT(in, 20), is_encrypted) << (20 ^ 24);
 116         ret |= crypto1_bit(s, BEBIT(in, 21), is_encrypted) << (21 ^ 24);
 117         ret |= crypto1_bit(s, BEBIT(in, 22), is_encrypted) << (22 ^ 24);
 118         ret |= crypto1_bit(s, BEBIT(in, 23), is_encrypted) << (23 ^ 24);
 119
 120         ret |= crypto1_bit(s, BEBIT(in, 24), is_encrypted) << (24 ^ 24);
 121         ret |= crypto1_bit(s, BEBIT(in, 25), is_encrypted) << (25 ^ 24);
 122         ret |= crypto1_bit(s, BEBIT(in, 26), is_encrypted) << (26 ^ 24);
 123         ret |= crypto1_bit(s, BEBIT(in, 27), is_encrypted) << (27 ^ 24);
 124         ret |= crypto1_bit(s, BEBIT(in, 28), is_encrypted) << (28 ^ 24);
 125         ret |= crypto1_bit(s, BEBIT(in, 29), is_encrypted) << (29 ^ 24);
 126         ret |= crypto1_bit(s, BEBIT(in, 30), is_encrypted) << (30 ^ 24);
 127         ret |= crypto1_bit(s, BEBIT(in, 31), is_encrypted) << (31 ^ 24);
 128         return ret;
 129 }
 130
 131 /* prng_successor
 132  * helper used to obscure the keystream during authentication
 133  */
 134 uint32_t prng_successor(uint32_t x, uint32_t n)
 135 {
 136         SWAPENDIAN(x);
 137         while(n--)
 138                 x = x >> 1 | (x >> 16 ^ x >> 18 ^ x >> 19 ^ x >> 21) << 31;
 139
 140         return SWAPENDIAN(x);
 141 }