#define filter(x) (filterlut[(x) & 0xfffff])\r
#endif\r
\r
+\r
+\r
+typedef struct bucket {\r
+ uint32_t *head;\r
+ uint32_t *bp;\r
+} bucket_t;\r
+\r
+typedef bucket_t bucket_array_t[2][0x100];\r
+\r
+typedef struct bucket_info {\r
+ struct {\r
+ uint32_t *head, *tail;\r
+ } bucket_info[2][0x100];\r
+ uint32_t numbuckets;\r
+ } bucket_info_t;\r
+ \r
+\r
+static void bucket_sort_intersect(uint32_t* const estart, uint32_t* const estop,\r
+ uint32_t* const ostart, uint32_t* const ostop,\r
+ bucket_info_t *bucket_info, bucket_array_t bucket)\r
+{\r
+ uint32_t *p1, *p2;\r
+ uint32_t *start[2];\r
+ uint32_t *stop[2];\r
+ \r
+ start[0] = estart;\r
+ stop[0] = estop;\r
+ start[1] = ostart;\r
+ stop[1] = ostop;\r
+ \r
+ // init buckets to be empty\r
+ for (uint32_t i = 0; i < 2; i++) {\r
+ for (uint32_t j = 0x00; j <= 0xff; j++) {\r
+ bucket[i][j].bp = bucket[i][j].head;\r
+ }\r
+ }\r
+ \r
+ // sort the lists into the buckets based on the MSB (contribution bits)\r
+ for (uint32_t i = 0; i < 2; i++) { \r
+ for (p1 = start[i]; p1 <= stop[i]; p1++) {\r
+ uint32_t bucket_index = (*p1 & 0xff000000) >> 24;\r
+ *(bucket[i][bucket_index].bp++) = *p1;\r
+ }\r
+ }\r
+\r
+ \r
+ // write back intersecting buckets as sorted list.\r
+ // fill in bucket_info with head and tail of the bucket contents in the list and number of non-empty buckets.\r
+ uint32_t nonempty_bucket;\r
+ for (uint32_t i = 0; i < 2; i++) {\r
+ p1 = start[i];\r
+ nonempty_bucket = 0;\r
+ for (uint32_t j = 0x00; j <= 0xff; j++) {\r
+ if (bucket[0][j].bp != bucket[0][j].head && bucket[1][j].bp != bucket[1][j].head) { // non-empty intersecting buckets only\r
+ bucket_info->bucket_info[i][nonempty_bucket].head = p1;\r
+ for (p2 = bucket[i][j].head; p2 < bucket[i][j].bp; *p1++ = *p2++);\r
+ bucket_info->bucket_info[i][nonempty_bucket].tail = p1 - 1;\r
+ nonempty_bucket++;\r
+ }\r
+ }\r
+ bucket_info->numbuckets = nonempty_bucket;\r
+ }\r
+}\r
+\r
+\r
static void quicksort(uint32_t* const start, uint32_t* const stop)\r
{\r
uint32_t *it = start + 1, *rit = stop;\r
quicksort(start, rit - 1);\r
quicksort(rit + 1, stop);\r
}\r
+\r
+\r
/** binsearch\r
* Binary search for the first occurence of *stop's MSB in sorted [start,stop]\r
*/\r
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
- if(filter(*tbl) ^ filter(*tbl | 1)) {\r
- *tbl |= filter(*tbl) ^ bit;\r
- update_contribution(tbl, m1, m2);\r
- *tbl ^= in;\r
- } else if(filter(*tbl) == bit) {\r
- *++*end = tbl[1];\r
- tbl[1] = tbl[0] | 1;\r
- update_contribution(tbl, m1, m2);\r
- *tbl++ ^= in;\r
- update_contribution(tbl, m1, m2);\r
- *tbl ^= in;\r
- } else\r
- *tbl-- = *(*end)--;\r
+\r
+ for(uint32_t *p = tbl; p <= *end; p++) {\r
+ *p <<= 1;\r
+ if(filter(*p) != filter(*p | 1)) { // replace\r
+ *p |= filter(*p) ^ bit;\r
+ update_contribution(p, m1, m2);\r
+ *p ^= in;\r
+ } else if(filter(*p) == bit) { // insert\r
+ *++*end = p[1];\r
+ p[1] = p[0] | 1;\r
+ update_contribution(p, m1, m2);\r
+ *p++ ^= in;\r
+ update_contribution(p, m1, m2);\r
+ *p ^= in;\r
+ } else { // drop\r
+ *p-- = *(*end)--;\r
+ } \r
+ }\r
+ \r
}\r
+\r
+\r
/** extend_table_simple\r
* using a bit of the keystream extend the table of possible lfsr states\r
*/\r
static inline void\r
extend_table_simple(uint32_t *tbl, uint32_t **end, int bit)\r
{\r
- for(*tbl <<= 1; tbl <= *end; *++tbl <<= 1)\r
- if(filter(*tbl) ^ filter(*tbl | 1)) {\r
+ for(*tbl <<= 1; tbl <= *end; *++tbl <<= 1) \r
+ if(filter(*tbl) ^ filter(*tbl | 1)) { // replace\r
*tbl |= filter(*tbl) ^ bit;\r
- } else if(filter(*tbl) == bit) {\r
+ } else if(filter(*tbl) == bit) { // insert\r
*++*end = *++tbl;\r
*tbl = tbl[-1] | 1;\r
- } else\r
+ } else // drop\r
*tbl-- = *(*end)--;\r
}\r
+\r
+\r
/** recover\r
* recursively narrow down the search space, 4 bits of keystream at a time\r
*/\r
static struct Crypto1State*\r
recover(uint32_t *o_head, uint32_t *o_tail, uint32_t oks,\r
uint32_t *e_head, uint32_t *e_tail, uint32_t eks, int rem,\r
- struct Crypto1State *sl, uint32_t in)\r
+ struct Crypto1State *sl, uint32_t in, bucket_array_t bucket)\r
{\r
- uint32_t *o, *e, i;\r
+ uint32_t *o, *e;\r
+ bucket_info_t bucket_info;\r
\r
if(rem == -1) {\r
for(e = e_head; e <= e_tail; ++e) {\r
for(o = o_head; o <= o_tail; ++o, ++sl) {\r
sl->even = *o;\r
sl->odd = *e ^ parity(*o & LF_POLY_ODD);\r
- sl[1].odd = sl[1].even = 0;\r
}\r
}\r
+ sl->odd = sl->even = 0;\r
return sl;\r
}\r
\r
- for(i = 0; i < 4 && rem--; i++) {\r
+ for(uint32_t 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
if(o_head > o_tail)\r
return sl;\r
}\r
\r
- quicksort(o_head, o_tail);\r
- quicksort(e_head, e_tail);\r
-\r
- while(o_tail >= o_head && e_tail >= e_head)\r
- if(((*o_tail ^ *e_tail) >> 24) == 0) {\r
- o_tail = binsearch(o_head, o = o_tail);\r
- e_tail = binsearch(e_head, e = e_tail);\r
- sl = recover(o_tail--, o, oks,\r
- e_tail--, e, eks, rem, sl, in);\r
- }\r
- else if(*o_tail > *e_tail)\r
- o_tail = binsearch(o_head, o_tail) - 1;\r
- else\r
- e_tail = binsearch(e_head, e_tail) - 1;\r
-\r
+ bucket_sort_intersect(e_head, e_tail, o_head, o_tail, &bucket_info, bucket);\r
+ \r
+ for (int i = bucket_info.numbuckets - 1; i >= 0; i--) {\r
+ sl = recover(bucket_info.bucket_info[1][i].head, bucket_info.bucket_info[1][i].tail, oks,\r
+ bucket_info.bucket_info[0][i].head, bucket_info.bucket_info[0][i].tail, eks,\r
+ rem, sl, in, bucket);\r
+ }\r
+ \r
return sl;\r
}\r
/** lfsr_recovery\r
uint32_t *even_head = 0, *even_tail = 0, eks = 0;\r
int i;\r
\r
+ // split the keystream into an odd and even part\r
for(i = 31; i >= 0; i -= 2)\r
oks = oks << 1 | BEBIT(ks2, i);\r
for(i = 30; i >= 0; i -= 2)\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
goto out;\r
-\r
+ }\r
statelist->odd = statelist->even = 0;\r
\r
+ // allocate memory for out of place bucket_sort\r
+ bucket_array_t bucket;\r
+ for (uint32_t i = 0; i < 2; i++)\r
+ for (uint32_t j = 0; j <= 0xff; j++) {\r
+ bucket[i][j].head = malloc(sizeof(uint32_t)<<14);\r
+ if (!bucket[i][j].head) {\r
+ goto out;\r
+ }\r
+ }\r
+\r
+ \r
+ // initialize statelists: add all possible states which would result into the rightmost 2 bits of the keystream\r
for(i = 1 << 20; i >= 0; --i) {\r
if(filter(i) == (oks & 1))\r
*++odd_tail = i;\r
*++even_tail = i;\r
}\r
\r
+ // extend the statelists. Look at the next 8 Bits of the keystream (4 Bit each odd and even):\r
for(i = 0; i < 4; i++) {\r
extend_table_simple(odd_head, &odd_tail, (oks >>= 1) & 1);\r
extend_table_simple(even_head, &even_tail, (eks >>= 1) & 1);\r
}\r
\r
- in = (in >> 16 & 0xff) | (in << 16) | (in & 0xff00);\r
+ // the statelists now contain all states which could have generated the last 10 Bits of the keystream.\r
+ // 22 bits to go to recover 32 bits in total. From now on, we need to take the "in"\r
+ // parameter into account.\r
+\r
+ in = (in >> 16 & 0xff) | (in << 16) | (in & 0xff00); // Byte swapping\r
+\r
recover(odd_head, odd_tail, oks,\r
- even_head, even_tail, eks, 11, statelist, in << 1);\r
+ even_head, even_tail, eks, 11, statelist, in << 1, bucket);\r
+\r
\r
out:\r
free(odd_head);\r
free(even_head);\r
+ for (uint32_t i = 0; i < 2; i++)\r
+ for (uint32_t j = 0; j <= 0xff; j++)\r
+ free(bucket[i][j].head);\r
+ \r
return statelist;\r
}\r
\r
projects / proxmark3-svn / blobdiff