79 lines
2.4 KiB
C++
79 lines
2.4 KiB
C++
|
#include "MD5.h"
|
|||
|
|
|
|||
|
|
void MD5::init() {
|
|||
|
|
count[0] = count[1] = 0;
|
|||
|
|
state[0] = 0x67452301;
|
|||
|
|
state[1] = 0xefcdab89;
|
|||
|
|
state[2] = 0x98badcfe;
|
|||
|
|
state[3] = 0x10325476;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
void MD5::update(const uint8_t* input, size_t length) {
|
|||
|
|
size_t index = (count[0] >> 3) & 0x3F;
|
|||
|
|
count[0] += static_cast<uint32_t>(length << 3);
|
|||
|
|
if (count[0] < (length << 3)) count[1]++;
|
|||
|
|
count[1] += static_cast<uint32_t>(length >> 29);
|
|||
|
|
size_t first_part = 64 - index;
|
|||
|
|
|
|||
|
|
size_t i = 0;
|
|||
|
|
if (length >= first_part) {
|
|||
|
|
std::memcpy(&buffer[index], input, first_part);
|
|||
|
|
transform(buffer);
|
|||
|
|
for (i = first_part; i + 63 < length; i += 64) transform(&input[i]);
|
|||
|
|
index = 0;
|
|||
|
|
}
|
|||
|
|
std::memcpy(&buffer[index], &input[i], length - i);
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
void MD5::finalize() {
|
|||
|
|
static const uint8_t padding[64] = { 0x80 };
|
|||
|
|
if (finalized) return;
|
|||
|
|
|
|||
|
|
uint8_t bits[8];
|
|||
|
|
encode(bits, count, 8);
|
|||
|
|
size_t index = (count[0] >> 3) & 0x3f;
|
|||
|
|
size_t pad_len = (index < 56) ? (56 - index) : (120 - index);
|
|||
|
|
update(padding, pad_len);
|
|||
|
|
update(bits, 8);
|
|||
|
|
|
|||
|
|
encode(digest, state, 16);
|
|||
|
|
finalized = true;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
std::string MD5::hexdigest() const {
|
|||
|
|
if (!finalized) return "";
|
|||
|
|
std::ostringstream result;
|
|||
|
|
for (int i = 0; i < 16; i++) result << std::hex << std::setw(2) << std::setfill('0') << (int)digest[i];
|
|||
|
|
return result.str();
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
void MD5::transform(const uint8_t block[64]) {
|
|||
|
|
uint32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16];
|
|||
|
|
decode(x, block, 64);
|
|||
|
|
|
|||
|
|
for (int i = 0; i < 64; i++) {
|
|||
|
|
if (i < 16) FF(a, b, c, d, x[i], S[i], K[i]);
|
|||
|
|
else if (i < 32) GG(a, b, c, d, x[(5 * i + 1) % 16], S[i], K[i]);
|
|||
|
|
else if (i < 48) HH(a, b, c, d, x[(3 * i + 5) % 16], S[i], K[i]);
|
|||
|
|
else II(a, b, c, d, x[(7 * i) % 16], S[i], K[i]);
|
|||
|
|
|
|||
|
|
uint32_t temp = d; d = c; c = b; b = a; a = temp;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
state[0] += a; state[1] += b; state[2] += c; state[3] += d;
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
void MD5::encode(uint8_t* output, const uint32_t* input, size_t length) {
|
|||
|
|
for (size_t i = 0, j = 0; j < length; i++, j += 4) {
|
|||
|
|
output[j] = input[i] & 0xff;
|
|||
|
|
output[j + 1] = (input[i] >> 8) & 0xff;
|
|||
|
|
output[j + 2] = (input[i] >> 16) & 0xff;
|
|||
|
|
output[j + 3] = (input[i] >> 24) & 0xff;
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
void MD5::decode(uint32_t* output, const uint8_t* input, size_t length) {
|
|||
|
|
for (size_t i = 0, j = 0; j < length; i++, j += 4) {
|
|||
|
|
output[i] = input[j] | (input[j + 1] << 8) | (input[j + 2] << 16) | (input[j + 3] << 24);
|
|||
|
|
}
|
|||
|
|
}
|