CHG: test of re-adding @piwi's bucketsort to @blapost's crapt1 v3.3 imp.

This commit is contained in:
iceman1001 2016-02-09 14:57:58 +01:00
parent 46a33c182d
commit 66afab80bd

View file

@ -24,36 +24,77 @@
static uint8_t filterlut[1 << 20];
static void __attribute__((constructor)) fill_lut()
{
uint32_t i;
for(i = 0; i < 1 << 20; ++i)
filterlut[i] = filter(i);
uint32_t i;
for(i = 0; i < 1 << 20; ++i)
filterlut[i] = filter(i);
}
#define filter(x) (filterlut[(x) & 0xfffff])
#endif
static void quicksort(uint32_t* const start, uint32_t* const stop)
typedef struct bucket {
uint32_t *head;
uint32_t *bp;
} bucket_t;
typedef bucket_t bucket_array_t[2][0x100];
typedef struct bucket_info {
struct {
uint32_t *head, *tail;
} bucket_info[2][0x100];
uint32_t numbuckets;
} bucket_info_t;
static void bucket_sort_intersect(uint32_t* const estart, uint32_t* const estop,
uint32_t* const ostart, uint32_t* const ostop,
bucket_info_t *bucket_info, bucket_array_t bucket)
{
uint32_t *it = start + 1, *rit = stop, t;
uint32_t *p1, *p2;
uint32_t *start[2];
uint32_t *stop[2];
if(it > rit)
return;
start[0] = estart;
stop[0] = estop;
start[1] = ostart;
stop[1] = ostop;
while(it < rit)
if(*it <= *start)
++it;
else if(*rit > *start)
--rit;
else
t = *it, *it = *rit, *rit = t;
// init buckets to be empty
for (uint32_t i = 0; i < 2; i++) {
for (uint32_t j = 0x00; j <= 0xff; j++) {
bucket[i][j].bp = bucket[i][j].head;
}
}
if(*rit >= *start)
--rit;
if(rit != start)
t = *rit, *rit = *start, *start = t;
// sort the lists into the buckets based on the MSB (contribution bits)
for (uint32_t i = 0; i < 2; i++) {
for (p1 = start[i]; p1 <= stop[i]; p1++) {
uint32_t bucket_index = (*p1 & 0xff000000) >> 24;
*(bucket[i][bucket_index].bp++) = *p1;
}
}
quicksort(start, rit - 1);
quicksort(rit + 1, stop);
// write back intersecting buckets as sorted list.
// fill in bucket_info with head and tail of the bucket contents in the list and number of non-empty buckets.
uint32_t nonempty_bucket;
for (uint32_t i = 0; i < 2; i++) {
p1 = start[i];
nonempty_bucket = 0;
for (uint32_t j = 0x00; j <= 0xff; j++) {
if (bucket[0][j].bp != bucket[0][j].head && bucket[1][j].bp != bucket[1][j].head) { // non-empty intersecting buckets only
bucket_info->bucket_info[i][nonempty_bucket].head = p1;
for (p2 = bucket[i][j].head; p2 < bucket[i][j].bp; *p1++ = *p2++);
bucket_info->bucket_info[i][nonempty_bucket].tail = p1 - 1;
nonempty_bucket++;
}
}
bucket_info->numbuckets = nonempty_bucket;
}
}
/** binsearch
* Binary search for the first occurence of *stop's MSB in sorted [start,stop]
*/
@ -126,9 +167,10 @@ static inline void extend_table_simple(uint32_t *tbl, uint32_t **end, int bit)
static struct Crypto1State*
recover(uint32_t *o_head, uint32_t *o_tail, uint32_t oks,
uint32_t *e_head, uint32_t *e_tail, uint32_t eks, int rem,
struct Crypto1State *sl, uint32_t in)
struct Crypto1State *sl, uint32_t in, bucket_array_t bucket)
{
uint32_t *o, *e, i;
uint32_t *o, *e;
bucket_info_t bucket_info;
if(rem == -1) {
for(e = e_head; e <= e_tail; ++e) {
@ -142,7 +184,7 @@ recover(uint32_t *o_head, uint32_t *o_tail, uint32_t oks,
return sl;
}
for(i = 0; i < 4 && rem--; i++) {
for(uint32_t i = 0; i < 4 && rem--; i++) {
oks >>= 1;
eks >>= 1;
in >>= 2;
@ -157,20 +199,13 @@ recover(uint32_t *o_head, uint32_t *o_tail, uint32_t oks,
return sl;
}
quicksort(o_head, o_tail);
quicksort(e_head, e_tail);
bucket_sort_intersect(e_head, e_tail, o_head, o_tail, &bucket_info, bucket);
while(o_tail >= o_head && e_tail >= e_head)
if(((*o_tail ^ *e_tail) >> 24) == 0) {
o_tail = binsearch(o_head, o = o_tail);
e_tail = binsearch(e_head, e = e_tail);
sl = recover(o_tail--, o, oks,
e_tail--, e, eks, rem, sl, in);
for (int i = bucket_info.numbuckets - 1; i >= 0; i--) {
sl = recover(bucket_info.bucket_info[1][i].head, bucket_info.bucket_info[1][i].tail, oks,
bucket_info.bucket_info[0][i].head, bucket_info.bucket_info[0][i].tail, eks,
rem, sl, in, bucket);
}
else if(*o_tail > *e_tail)
o_tail = binsearch(o_head, o_tail) - 1;
else
e_tail = binsearch(e_head, e_tail) - 1;
return sl;
}
@ -203,6 +238,17 @@ struct Crypto1State* lfsr_recovery32(uint32_t ks2, uint32_t in)
statelist->odd = statelist->even = 0;
// allocate memory for out of place bucket_sort
bucket_array_t bucket;
for (uint32_t i = 0; i < 2; i++)
for (uint32_t j = 0; j <= 0xff; j++) {
bucket[i][j].head = malloc(sizeof(uint32_t)<<14);
if (!bucket[i][j].head) {
goto out;
}
}
// initialize statelists: add all possible states which would result into the rightmost 2 bits of the keystream
for(i = 1 << 20; i >= 0; --i) {
if(filter(i) == (oks & 1))
@ -220,13 +266,18 @@ struct Crypto1State* lfsr_recovery32(uint32_t ks2, uint32_t in)
// the statelists now contain all states which could have generated the last 10 Bits of the keystream.
// 22 bits to go to recover 32 bits in total. From now on, we need to take the "in"
// parameter into account.
in = (in >> 16 & 0xff) | (in << 16) | (in & 0xff00);
in = (in >> 16 & 0xff) | (in << 16) | (in & 0xff00); // Byte swapping
recover(odd_head, odd_tail, oks,
even_head, even_tail, eks, 11, statelist, in << 1);
even_head, even_tail, eks, 11, statelist, in << 1, bucket);
out:
free(odd_head);
free(even_head);
for (uint32_t i = 0; i < 2; i++)
for (uint32_t j = 0; j <= 0xff; j++)
free(bucket[i][j].head);
return statelist;
}