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Build and link mhycrypto statically

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ayy lmao
2022-07-06 16:26:35 +03:00
committed by lilmayofuksu
parent e0272aa38a
commit 850b282b70
11 changed files with 791 additions and 25 deletions
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128
src-tauri/mhycrypto/metadata.cpp Normal file
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#include "metadata.h"
#include <cstring>
#include <random>
#include <stdio.h>
#include "memecrypto.h"
#include "metadatastringdec.h"
unsigned char initial_prev_xor[] = { 0xad, 0x2f, 0x42, 0x30, 0x67, 0x04, 0xb0, 0x9c, 0x9d, 0x2a, 0xc0, 0xba, 0x0e, 0xbf, 0xa5, 0x68 };
bool get_global_metadata_keys(uint8_t *src, size_t srcn, uint8_t *longkey, uint8_t *shortkey) {
if (srcn != 0x4000)
return false;
if (*(uint16_t *) (src + 0xc8) != 0xfc2e || *(uint16_t *) (src + 0xca) != 0x2cfe)
return true;
auto offB00 = *(uint16_t *) (src + 0xd2);
for (size_t i = 0; i < 16; i++)
shortkey[i] = src[offB00 + i] ^ src[0x3000 + i];
for (size_t i = 0; i < 0xb00; i++)
longkey[i] = src[offB00 + 0x10 + i] ^ src[0x3000 + 0x10 + i] ^ shortkey[i % 16];
return true;
}
bool gen_global_metadata_key(uint8_t* src, size_t srcn) {
if (srcn != 0x4000)
return false;
#if 0
std::vector<uint8_t> read_file(const char* n);
auto data = read_file("xorpad.bin");
memcpy(src, data.data(), 0x4000);
return false;
#endif
std::mt19937_64 rand (0xDEADBEEF);
uint64_t* key = (uint64_t*)src;
for (int i = 0; i < srcn / sizeof(uint64_t); i++)
key[i] = rand();
*(uint16_t *) (src + 0xc8) = 0xfc2e; // Magic
*(uint16_t *) (src + 0xca) = 0x2cfe; // Magic
*(uint16_t *) (src + 0xd2) = rand() & 0x1FFFu; // Just some random value
return true;
}
extern "C" void decrypt_global_metadata(uint8_t *data, size_t size) {
uint8_t longkey[0xB00];
uint8_t longkeyp[0xB0];
uint8_t shortkey[16];
get_global_metadata_keys(data + size - 0x4000, 0x4000, longkey, shortkey);
for (int i = 0; i < 16; i++)
shortkey[i] ^= initial_prev_xor[i];
memecrypto_prepare_key(longkey, longkeyp);
auto perentry = (uint32_t) (size / 0x100 / 0x40);
for (int i = 0; i < 0x100; i++) {
auto off = (0x40u * perentry) * i;
uint8_t prev[16];
memcpy(prev, shortkey, 16);
for (int j = 0; j < 4; j++) {
uint8_t curr[16];
memcpy(curr, &data[off + j * 0x10], 16);
memecrypto_decrypt(longkeyp, curr);
for (int k = 0; k < 16; k++)
curr[k] ^= prev[k];
memcpy(prev, &data[off + j * 0x10], 16);
memcpy(&data[off + j * 0x10], curr, 16);
}
}
uint8_t literal_dec_key[0x5000];
recrypt_global_metadata_header_string_fields(data, size, literal_dec_key);
recrypt_global_metadata_header_string_literals(data, size, literal_dec_key);
}
extern "C" void encrypt_global_metadata(uint8_t* data, size_t size) {
uint8_t literal_dec_key[0x5000];
gen_global_metadata_key(data + size - 0x4000, 0x4000);
generate_key_for_global_metadata_header_string(data, size, literal_dec_key);
recrypt_global_metadata_header_string_literals(data, size, literal_dec_key);
recrypt_global_metadata_header_string_fields(data, size, literal_dec_key);
uint8_t longkey[0xB00];
uint8_t longkeyp[0xB0];
uint8_t shortkey[16];
get_global_metadata_keys(data + size - 0x4000, 0x4000, longkey, shortkey);
for (int i = 0; i < 16; i++)
shortkey[i] ^= initial_prev_xor[i];
memecrypto_prepare_key(longkey, longkeyp);
auto perentry = (uint32_t) (size / 0x100 / 0x40);
for (int i = 0; i < 0x100; i++) {
auto off = (0x40u * perentry) * i;
uint8_t prev[16];
memcpy(prev, shortkey, 16);
for (int j = 0; j < 4; j++) {
uint8_t curr[16];
memcpy(curr, &data[off + j * 0x10], 16);
for (int k = 0; k < 16; k++)
curr[k] ^= prev[k];
memecrypto_encrypt(longkeyp, curr);
memcpy(prev, curr, 16);
memcpy(&data[off + j * 0x10], curr, 16);
}
}
}