\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
/** binsearch\r
* Binary search for the first occurence of *stop's MSB in sorted [start,stop]\r
*/\r
-static inline uint32_t*\r
-binsearch(uint32_t *start, uint32_t *stop)\r
+static inline uint32_t* binsearch(uint32_t *start, uint32_t *stop)\r
{\r
uint32_t mid, val = *stop & 0xff000000;\r
while(start != stop)\r
}\r
\r
for(i = 0; i < 4 && rem--; i++) {\r
- extend_table(o_head, &o_tail, (oks >>= 1) & 1,\r
- LF_POLY_EVEN << 1 | 1, LF_POLY_ODD << 1, 0);\r
+ oks >>= 1;\r
+ eks >>= 1;\r
+ in >>= 2;\r
+ extend_table(o_head, &o_tail, oks & 1, LF_POLY_EVEN << 1 | 1,\r
+ LF_POLY_ODD << 1, 0);\r
if(o_head > o_tail)\r
return sl;\r
\r
- extend_table(e_head, &e_tail, (eks >>= 1) & 1,\r
- LF_POLY_ODD, LF_POLY_EVEN << 1 | 1, (in >>= 2) & 3);\r
+ extend_table(e_head, &e_tail, eks & 1, LF_POLY_ODD,\r
+ LF_POLY_EVEN << 1 | 1, in & 3);\r
if(e_head > e_tail)\r
return sl;\r
}\r
odd_head = odd_tail = malloc(sizeof(uint32_t) << 21);\r
even_head = even_tail = malloc(sizeof(uint32_t) << 21);\r
statelist = malloc(sizeof(struct Crypto1State) << 18);\r
- if(!odd_tail-- || !even_tail-- || !statelist)\r
+ if(!odd_tail-- || !even_tail-- || !statelist) {\r
+ free(statelist);\r
+ statelist = 0;\r
goto out;\r
+ }\r
\r
statelist->odd = statelist->even = 0;\r
\r
sl->odd = sl->even = 0;\r
\r
for(i = 30; i >= 0; i -= 2) {\r
- oks[i >> 1] = BIT(ks2, i ^ 24);\r
- oks[16 + (i >> 1)] = BIT(ks3, i ^ 24);\r
+ oks[i >> 1] = BEBIT(ks2, i);\r
+ oks[16 + (i >> 1)] = BEBIT(ks3, i);\r
}\r
for(i = 31; i >= 0; i -= 2) {\r
- eks[i >> 1] = BIT(ks2, i ^ 24);\r
- eks[16 + (i >> 1)] = BIT(ks3, i ^ 24);\r
+ eks[i >> 1] = BEBIT(ks2, i);\r
+ eks[16 + (i >> 1)] = BEBIT(ks3, i);\r
}\r
\r
for(i = 0xfffff; i >= 0; --i) {\r
/** lfsr_rollback_bit\r
* Rollback the shift register in order to get previous states\r
*/\r
-void lfsr_rollback_bit(struct Crypto1State *s, uint32_t in, int fb)\r
+uint8_t lfsr_rollback_bit(struct Crypto1State *s, uint32_t in, int fb)\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
out ^= LF_POLY_ODD & s->odd;\r
out ^= !!in;\r
- out ^= filter(s->odd) & !!fb;\r
+ out ^= (ret = filter(s->odd)) & !!fb;\r
\r
s->even |= parity(out) << 23;\r
+ return ret;\r
}\r
/** lfsr_rollback_byte\r
* Rollback the shift register in order to get previous states\r
*/\r
-void lfsr_rollback_byte(struct Crypto1State *s, uint32_t in, int fb)\r
+uint8_t lfsr_rollback_byte(struct Crypto1State *s, uint32_t in, int fb)\r
{\r
- int i;\r
+ int i, ret = 0;\r
for (i = 7; i >= 0; --i)\r
- lfsr_rollback_bit(s, BEBIT(in, i), fb);\r
+ ret |= lfsr_rollback_bit(s, BIT(in, i), fb) << i;\r
+ return ret;\r
}\r
/** lfsr_rollback_word\r
* Rollback the shift register in order to get previous states\r
*/\r
-void lfsr_rollback_word(struct Crypto1State *s, uint32_t in, int fb)\r
+uint32_t lfsr_rollback_word(struct Crypto1State *s, uint32_t in, int fb)\r
{\r
int i;\r
+ uint32_t ret = 0;\r
for (i = 31; i >= 0; --i)\r
- lfsr_rollback_bit(s, BEBIT(in, i), fb);\r
+ ret |= lfsr_rollback_bit(s, BEBIT(in, i), fb) << (i ^ 24);\r
+ return ret;\r
}\r
\r
/** nonce_distance\r
* Described in the "dark side" paper. It returns an -1 terminated array\r
* of possible partial(21 bit) secret state.\r
* The required keystream(ks) needs to contain the keystream that was used to\r
- * encrypt the NACK which is observed when varying only the 4 last bits of Nr\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
uint32_t *lfsr_prefix_ks(uint8_t ks[8], int isodd)\r
{\r
- uint32_t *candidates = malloc(4 << 21);\r
- uint32_t c, entry;\r
- int size, i;\r
+ uint32_t c, entry, *candidates = malloc(4 << 10);\r
+ int i, size = 0, good;\r
\r
if(!candidates)\r
return 0;\r
\r
- size = (1 << 21) - 1;\r
- for(i = 0; i <= size; ++i)\r
- candidates[i] = i;\r
-\r
- for(c = 0; c < 8; ++c)\r
- for(i = 0;i <= size; ++i) {\r
- entry = candidates[i] ^ fastfwd[isodd][c];\r
-\r
- if(filter(entry >> 1) == BIT(ks[c], isodd))\r
- if(filter(entry) == BIT(ks[c], isodd + 2))\r
- continue;\r
-\r
- candidates[i--] = candidates[size--];\r
+ for(i = 0; i < 1 << 21; ++i) {\r
+ for(c = 0, good = 1; good && c < 8; ++c) {\r
+ entry = i ^ fastfwd[isodd][c];\r
+ good &= (BIT(ks[c], isodd) == filter(entry >> 1));\r
+ good &= (BIT(ks[c], isodd + 2) == filter(entry));\r
}\r
+ if(good)\r
+ candidates[size++] = i;\r
+ }\r
\r
- candidates[size + 1] = -1;\r
+ candidates[size] = -1;\r
\r
return candidates;\r
}\r
\r
-/** brute_top\r
+/** check_pfx_parity\r
* helper function which eliminates possible secret states using parity bits\r
*/\r
static struct Crypto1State*\r
-brute_top(uint32_t prefix, uint32_t rresp, unsigned char parities[8][8],\r
+check_pfx_parity(uint32_t prefix, uint32_t rresp, uint8_t parities[8][8],\r
uint32_t odd, uint32_t even, struct Crypto1State* sl)\r
{\r
- struct Crypto1State s;\r
- uint32_t ks1, nr, ks2, rr, ks3, good, c;\r
-\r
- for(c = 0; c < 8; ++c) {\r
- s.odd = odd ^ fastfwd[1][c];\r
- s.even = even ^ fastfwd[0][c];\r
- \r
- lfsr_rollback_bit(&s, 0, 0);\r
- lfsr_rollback_bit(&s, 0, 0);\r
- lfsr_rollback_bit(&s, 0, 0);\r
- \r
- lfsr_rollback_word(&s, 0, 0);\r
- lfsr_rollback_word(&s, prefix | c << 5, 1);\r
- \r
- sl->odd = s.odd;\r
- sl->even = s.even;\r
- \r
- ks1 = crypto1_word(&s, prefix | c << 5, 1);\r
- ks2 = crypto1_word(&s,0,0);\r
- ks3 = crypto1_word(&s, 0,0);\r
+ uint32_t ks1, nr, ks2, rr, ks3, c, good = 1;\r
+\r
+ for(c = 0; good && c < 8; ++c) {\r
+ sl->odd = odd ^ fastfwd[1][c];\r
+ sl->even = even ^ fastfwd[0][c];\r
+\r
+ lfsr_rollback_bit(sl, 0, 0);\r
+ lfsr_rollback_bit(sl, 0, 0);\r
+\r
+ ks3 = lfsr_rollback_bit(sl, 0, 0);\r
+ ks2 = lfsr_rollback_word(sl, 0, 0);\r
+ ks1 = lfsr_rollback_word(sl, prefix | c << 5, 1);\r
+\r
nr = ks1 ^ (prefix | c << 5);\r
rr = ks2 ^ rresp;\r
\r
- good = 1;\r
good &= parity(nr & 0x000000ff) ^ parities[c][3] ^ BIT(ks2, 24);\r
good &= parity(rr & 0xff000000) ^ parities[c][4] ^ BIT(ks2, 16);\r
good &= parity(rr & 0x00ff0000) ^ parities[c][5] ^ BIT(ks2, 8);\r
good &= parity(rr & 0x0000ff00) ^ parities[c][6] ^ BIT(ks2, 0);\r
- good &= parity(rr & 0x000000ff) ^ parities[c][7] ^ BIT(ks3, 24);\r
-\r
- if(!good)\r
- return sl;\r
+ good &= parity(rr & 0x000000ff) ^ parities[c][7] ^ ks3;\r
}\r
\r
- return ++sl;\r
+ return sl + good;\r
} \r
\r
\r
odd = lfsr_prefix_ks(ks, 1);\r
even = lfsr_prefix_ks(ks, 0);\r
\r
- statelist = malloc((sizeof *statelist) << 20);\r
- if(!statelist || !odd || !even)\r
- return 0;\r
-\r
+ s = statelist = malloc((sizeof *statelist) << 20);\r
+ if(!s || !odd || !even) {\r
+ free(statelist);\r
+ statelist = 0;\r
+ goto out;\r
+ }\r
\r
- s = statelist;\r
- for(o = odd; *o != 0xffffffff; ++o)\r
- for(e = even; *e != 0xffffffff; ++e)\r
+ for(o = odd; *o + 1; ++o)\r
+ for(e = even; *e + 1; ++e)\r
for(top = 0; top < 64; ++top) {\r
- *o = (*o & 0x1fffff) | (top << 21);\r
- *e = (*e & 0x1fffff) | (top >> 3) << 21;\r
- s = brute_top(pfx, rr, par, *o, *e, s);\r
+ *o += 1 << 21;\r
+ *e += (!(top & 7) + 1) << 21;\r
+ s = check_pfx_parity(pfx, rr, par, *o, *e, s);\r
}\r
\r
s->odd = s->even = 0;\r
-\r
+out:\r
free(odd);\r
free(even);\r
-\r
return statelist;\r
}\r
projects / proxmark3-svn / commitdiff