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ADD: started to add tracelog in legic

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ADD: remake of legic codebase.
ADD: started with a annotation for LEGIC in 'hf list'
This commit is contained in:
iceman1001 2016-09-02 16:25:54 +02:00
commit c71c5ee156
8 changed files with 526 additions and 447 deletions
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40
common/legic_prng.c
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@ -9,35 +9,33 @@
#include "legic_prng.h"
struct lfsr {
uint8_t a;
uint8_t b;
uint32_t c;
uint8_t a;
uint8_t b;
uint32_t c;
} lfsr;
void legic_prng_init(uint8_t init) {
lfsr.c = 0;
lfsr.a = init;
if(init == 0) /* hack to get a always 0 keystream */
lfsr.b = 0;
else
lfsr.b = (init << 1) | 1;
lfsr.a = init;
lfsr.b = 0; // hack to get a always 0 keystream
lfsr.c = 0;
if(init)
lfsr.b = (init << 1) | 1;
}
void legic_prng_forward(int count) {
lfsr.c += count;
while(count--) {
//lfsr.a = lfsr.a >> 1 | (lfsr.a ^ lfsr.a >> 6) << 6;
// According: http://www.proxmark.org/forum/viewtopic.php?pid=5437#p5437
lfsr.a = (lfsr.a >> 1 | (lfsr.a ^ lfsr.a >> 6) << 6) & 0x7F;
lfsr.b = lfsr.b >> 1 | (lfsr.b ^ lfsr.b >> 2 ^ lfsr.b >> 3 ^ lfsr.b >> 7) << 7;
}
lfsr.c += count;
while(count--) {
// According: http://www.proxmark.org/forum/viewtopic.php?pid=5437#p5437
lfsr.a = (lfsr.a >> 1 | (lfsr.a ^ lfsr.a >> 6) << 6) & 0x7F;
lfsr.b = lfsr.b >> 1 | (lfsr.b ^ lfsr.b >> 2 ^ lfsr.b >> 3 ^ lfsr.b >> 7) << 7;
}
}
int legic_prng_count() {
return lfsr.c;
uint32_t legic_prng_count() {
return lfsr.c;
}
uint8_t legic_prng_get_bit() {
uint8_t idx = 7 - ( (lfsr.a & 4) | (lfsr.a >> 2 & 2) | (lfsr.a >> 4 & 1) );
return lfsr.b >> idx & 1;
}
uint8_t idx = 7 - ( (lfsr.a & 4) | (lfsr.a >> 2 & 2) | (lfsr.a >> 4 & 1) );
return lfsr.b >> idx & 1;
}