\r
static void quicksort(uint32_t* const start, uint32_t* const stop)\r
{\r
- uint32_t *it = start + 1, *rit = stop;\r
+ uint32_t *it = start + 1, *rit = stop, t;\r
\r
if(it > rit)\r
return;\r
else if(*rit > *start)\r
--rit;\r
else\r
- *it ^= ( (*it ^= *rit ), *rit ^= *it);\r
+ t = *it, *it = *rit, *rit = t;\r
\r
if(*rit >= *start)\r
--rit;\r
if(rit != start)\r
- *rit ^= ( (*rit ^= *start), *start ^= *rit);\r
+ t = *rit, *rit = *start, *start = t;\r
\r
quicksort(start, rit - 1);\r
quicksort(rit + 1, stop);\r
/** extend_table\r
* using a bit of the keystream extend the table of possible lfsr states\r
*/\r
-static inline void\r
-extend_table(uint32_t *tbl, uint32_t **end, int bit, int m1, int m2, uint32_t in)\r
+static inline void extend_table(uint32_t *tbl, uint32_t **end, int bit, int m1, int m2, uint32_t in)\r
{\r
in <<= 24;\r
for(*tbl <<= 1; tbl <= *end; *++tbl <<= 1)\r
{\r
int out;\r
uint8_t ret;\r
+ uint32_t t;\r
\r
s->odd &= 0xffffff;\r
- s->odd ^= (s->odd ^= s->even, s->even ^= s->odd);\r
+ t = s->odd, s->odd = s->even, s->even = t;\r
\r
out = s->even & 1;\r
out ^= LF_POLY_EVEN & (s->even >>= 1);\r
*/\r
uint8_t lfsr_rollback_byte(struct Crypto1State *s, uint32_t in, int fb)\r
{\r
+ /*\r
int i, ret = 0;\r
for (i = 7; i >= 0; --i)\r
ret |= lfsr_rollback_bit(s, BIT(in, i), fb) << i;\r
+*/\r
+// unfold loop 20160112\r
+ uint8_t ret = 0;\r
+ ret |= lfsr_rollback_bit(s, BIT(in, 7), fb) << 7;\r
+ ret |= lfsr_rollback_bit(s, BIT(in, 6), fb) << 6;\r
+ ret |= lfsr_rollback_bit(s, BIT(in, 5), fb) << 5;\r
+ ret |= lfsr_rollback_bit(s, BIT(in, 4), fb) << 4;\r
+ ret |= lfsr_rollback_bit(s, BIT(in, 3), fb) << 3;\r
+ ret |= lfsr_rollback_bit(s, BIT(in, 2), fb) << 2;\r
+ ret |= lfsr_rollback_bit(s, BIT(in, 1), fb) << 1;\r
+ ret |= lfsr_rollback_bit(s, BIT(in, 0), fb) << 0;\r
return ret;\r
}\r
/** lfsr_rollback_word\r
*/\r
uint32_t lfsr_rollback_word(struct Crypto1State *s, uint32_t in, int fb)\r
{\r
+ /*\r
int i;\r
uint32_t ret = 0;\r
for (i = 31; i >= 0; --i)\r
ret |= lfsr_rollback_bit(s, BEBIT(in, i), fb) << (i ^ 24);\r
+*/\r
+// unfold loop 20160112\r
+ uint32_t ret = 0;\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 31), fb) << (31 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 30), fb) << (30 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 29), fb) << (29 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 28), fb) << (28 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 27), fb) << (27 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 26), fb) << (26 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 25), fb) << (25 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 24), fb) << (24 ^ 24);\r
+\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 23), fb) << (23 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 22), fb) << (22 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 21), fb) << (21 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 20), fb) << (20 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 19), fb) << (19 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 18), fb) << (18 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 17), fb) << (17 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 16), fb) << (16 ^ 24);\r
+\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 15), fb) << (15 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 14), fb) << (14 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 13), fb) << (13 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 12), fb) << (12 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 11), fb) << (11 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 10), fb) << (10 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 9), fb) << (9 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 8), fb) << (8 ^ 24);\r
+\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 7), fb) << (7 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 6), fb) << (6 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 5), fb) << (5 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 4), fb) << (4 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 3), fb) << (3 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 2), fb) << (2 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 1), fb) << (1 ^ 24);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, 0), fb) << (0 ^ 24);\r
return ret;\r
}\r
\r
static uint32_t fastfwd[2][8] = {\r
{ 0, 0x4BC53, 0xECB1, 0x450E2, 0x25E29, 0x6E27A, 0x2B298, 0x60ECB},\r
{ 0, 0x1D962, 0x4BC53, 0x56531, 0xECB1, 0x135D3, 0x450E2, 0x58980}};\r
+\r
+\r
/** lfsr_prefix_ks\r
*\r
* Is an exported helper function from the common prefix attack\r
* encrypt the NACK which is observed when varying only the 3 last bits of Nr\r
* only correct iff [NR_3] ^ NR_3 does not depend on Nr_3\r
*/\r
+ // TO VERIFY \r
uint32_t *lfsr_prefix_ks(uint8_t ks[8], int isodd)\r
{\r
- uint32_t c, entry, *candidates = malloc(4 << 10);\r
- int i, size = 0, good;\r
+ uint32_t *candidates = malloc(4 << 10);\r
+ uint32_t c, entry;\r
+ int size = 0, i, good;\r
\r
if(!candidates)\r
return 0;\r
}\r
\r
return sl + good;\r
-} \r
+}\r
\r
\r
/** lfsr_common_prefix\r
* Implentation of the common prefix attack.\r
+ * Requires the 28 bit constant prefix used as reader nonce (pfx)\r
+ * The reader response used (rr)\r
+ * The keystream used to encrypt the observed NACK's (ks)\r
+ * The parity bits (par)\r
+ * It returns a zero terminated list of possible cipher states after the\r
+ * tag nonce was fed in\r
*/\r
struct Crypto1State*\r
lfsr_common_prefix(uint32_t pfx, uint32_t rr, uint8_t ks[8], uint8_t par[8][8])\r
s = statelist = malloc((sizeof *statelist) << 20);\r
if(!s || !odd || !even) {\r
free(statelist);\r
- statelist = 0;\r
- goto out;\r
+ free(odd);\r
+ free(even);\r
+ return 0;\r
}\r
\r
for(o = odd; *o + 1; ++o)\r
}\r
\r
s->odd = s->even = 0;\r
-out:\r
+\r
free(odd);\r
free(even);\r
+\r
return statelist;\r
}\r
projects / proxmark3-svn / blobdiff