Extend byte array expansion and compression methods with optional padding
This commit is contained in:
parent
caa0348f04
commit
20abe2083c
|
@ -53,12 +53,12 @@ void GenerateHash(const eh_HashState& base_state, eh_index g,
|
|||
|
||||
void ExpandArray(const unsigned char* in, size_t in_len,
|
||||
unsigned char* out, size_t out_len,
|
||||
size_t bit_len)
|
||||
size_t bit_len, size_t byte_pad)
|
||||
{
|
||||
assert(bit_len >= 8);
|
||||
assert(8*sizeof(uint32_t) >= 7+bit_len);
|
||||
|
||||
size_t out_width { (bit_len+7)/8 };
|
||||
size_t out_width { (bit_len+7)/8 + byte_pad };
|
||||
assert(out_len == 8*out_width*in_len/bit_len);
|
||||
|
||||
uint32_t bit_len_mask { ((uint32_t)1 << bit_len) - 1 };
|
||||
|
@ -77,7 +77,10 @@ void ExpandArray(const unsigned char* in, size_t in_len,
|
|||
// output element.
|
||||
if (acc_bits >= bit_len) {
|
||||
acc_bits -= bit_len;
|
||||
for (size_t x = 0; x < out_width; x++) {
|
||||
for (size_t x = 0; x < byte_pad; x++) {
|
||||
out[j+x] = 0;
|
||||
}
|
||||
for (size_t x = byte_pad; x < out_width; x++) {
|
||||
out[j+x] = (
|
||||
// Big-endian
|
||||
acc_value >> (acc_bits+(8*(out_width-x-1)))
|
||||
|
@ -93,12 +96,12 @@ void ExpandArray(const unsigned char* in, size_t in_len,
|
|||
|
||||
void CompressArray(const unsigned char* in, size_t in_len,
|
||||
unsigned char* out, size_t out_len,
|
||||
size_t bit_len)
|
||||
size_t bit_len, size_t byte_pad)
|
||||
{
|
||||
assert(bit_len >= 8);
|
||||
assert(8*sizeof(uint32_t) >= 7+bit_len);
|
||||
|
||||
size_t in_width { (bit_len+7)/8 };
|
||||
size_t in_width { (bit_len+7)/8 + byte_pad };
|
||||
assert(out_len == bit_len*in_len/(8*in_width));
|
||||
|
||||
uint32_t bit_len_mask { ((uint32_t)1 << bit_len) - 1 };
|
||||
|
@ -114,7 +117,7 @@ void CompressArray(const unsigned char* in, size_t in_len,
|
|||
// input element.
|
||||
if (acc_bits < 8) {
|
||||
acc_value = acc_value << bit_len;
|
||||
for (size_t x = 0; x < in_width; x++) {
|
||||
for (size_t x = byte_pad; x < in_width; x++) {
|
||||
acc_value = acc_value | (
|
||||
(
|
||||
// Apply bit_len_mask across byte boundaries
|
||||
|
|
|
@ -26,10 +26,10 @@ typedef uint8_t eh_trunc;
|
|||
|
||||
void ExpandArray(const unsigned char* in, size_t in_len,
|
||||
unsigned char* out, size_t out_len,
|
||||
size_t bit_len);
|
||||
size_t bit_len, size_t byte_pad=0);
|
||||
void CompressArray(const unsigned char* in, size_t in_len,
|
||||
unsigned char* out, size_t out_len,
|
||||
size_t bit_len);
|
||||
size_t bit_len, size_t byte_pad=0);
|
||||
|
||||
eh_index ArrayToEhIndex(const unsigned char* array);
|
||||
eh_trunc TruncateIndex(const eh_index i, const unsigned int ilen);
|
||||
|
|
|
@ -4,31 +4,37 @@
|
|||
#include "crypto/equihash.h"
|
||||
#include "uint256.h"
|
||||
|
||||
void TestExpandAndCompress(const std::string &scope, size_t bit_len,
|
||||
void TestExpandAndCompress(const std::string &scope, size_t bit_len, size_t byte_pad,
|
||||
std::vector<unsigned char> compact,
|
||||
std::vector<unsigned char> expanded)
|
||||
{
|
||||
SCOPED_TRACE(scope);
|
||||
|
||||
std::vector<unsigned char> out(expanded.size());
|
||||
ExpandArray(compact.data(), compact.size(), out.data(), out.size(), bit_len);
|
||||
ExpandArray(compact.data(), compact.size(),
|
||||
out.data(), out.size(), bit_len, byte_pad);
|
||||
EXPECT_EQ(expanded, out);
|
||||
|
||||
out.resize(compact.size());
|
||||
CompressArray(expanded.data(), expanded.size(), out.data(), out.size(), bit_len);
|
||||
CompressArray(expanded.data(), expanded.size(),
|
||||
out.data(), out.size(), bit_len, byte_pad);
|
||||
EXPECT_EQ(compact, out);
|
||||
}
|
||||
|
||||
TEST(equihash_tests, expand_and_contract_arrays) {
|
||||
TestExpandAndCompress("8 11-bit chunks, all-ones", 11,
|
||||
TestExpandAndCompress("8 11-bit chunks, all-ones", 11, 0,
|
||||
ParseHex("ffffffffffffffffffffff"),
|
||||
ParseHex("07ff07ff07ff07ff07ff07ff07ff07ff"));
|
||||
TestExpandAndCompress("8 21-bit chunks, alternating 1s and 0s", 21,
|
||||
TestExpandAndCompress("8 21-bit chunks, alternating 1s and 0s", 21, 0,
|
||||
ParseHex("aaaaad55556aaaab55555aaaaad55556aaaab55555"),
|
||||
ParseHex("155555155555155555155555155555155555155555155555"));
|
||||
TestExpandAndCompress("16 14-bit chunks, alternating 11s and 00s", 14,
|
||||
TestExpandAndCompress("16 14-bit chunks, alternating 11s and 00s", 14, 0,
|
||||
ParseHex("cccf333cccf333cccf333cccf333cccf333cccf333cccf333cccf333"),
|
||||
ParseHex("3333333333333333333333333333333333333333333333333333333333333333"));
|
||||
|
||||
TestExpandAndCompress("8 11-bit chunks, all-ones, 2-byte padding", 11, 2,
|
||||
ParseHex("ffffffffffffffffffffff"),
|
||||
ParseHex("000007ff000007ff000007ff000007ff000007ff000007ff000007ff000007ff"));
|
||||
}
|
||||
|
||||
TEST(equihash_tests, is_probably_duplicate) {
|
||||
|
|
Loading…
Reference in New Issue