PC微信逆向：破解聊天记录文件！

using namespace std;#include <Windows.h>#include <iostream>#include <openssl/rand.h>#include <openssl/evp.h>#include <openssl/aes.h>#include <openssl/hmac.h>
#undef _UNICODE#define SQLITE_FILE_HEADER "SQLite format 3" #define IV_SIZE 16#define HMAC_SHA1_SIZE 20#define KEY_SIZE 32
#define SL3SIGNLEN 20
#ifndef ANDROID_WECHAT#define DEFAULT_PAGESIZE 4096       //4048数据 + 16IV + 20 HMAC + 12#define DEFAULT_ITER 64000#else#define NO_USE_HMAC_SHA1#define DEFAULT_PAGESIZE 1024#define DEFAULT_ITER 4000#endif//pc端密码是经过OllyDbg得到的32位pass。unsigned char pass[] = { 0x53,0xE9,0xBF,0xB2,0x3B,0x72,0x41,0x95,0xA2,0xBC,0x6E,0xB5,0xBF,0xEB,0x06,0x10,0xDC,0x21,0x64,0x75,0x6B,0x9B,0x42,0x79,0xBA,0x32,0x15,0x76,0x39,0xA4,0x0B,0xB1 };char dbfilename[50];int Decryptdb();int CheckKey();int CheckAESKey();int main(int argc, char* argv[]){    if (argc >= 2)    //第二个参数argv[1]是文件名        strcpy_s(dbfilename, argv[1]);  //复制               //没有提供文件名，则提示用户输入    else {        cout << "请输入文件名:" << endl;        cin >> dbfilename;    }    Decryptdb();    return 0;}
int Decryptdb(){    FILE* fpdb;    fopen_s(&fpdb, dbfilename, "rb+");    if (!fpdb)    {        printf("打开文件错!");        getchar();        return 0;    }    fseek(fpdb, 0, SEEK_END);    long nFileSize = ftell(fpdb);    fseek(fpdb, 0, SEEK_SET);    unsigned char* pDbBuffer = new unsigned char[nFileSize];    fread(pDbBuffer, 1, nFileSize, fpdb);    fclose(fpdb);
    unsigned char salt[16] = { 0 };    memcpy(salt, pDbBuffer, 16);
#ifndef NO_USE_HMAC_SHA1    unsigned char mac_salt[16] = { 0 };    memcpy(mac_salt, salt, 16);    for (int i = 0; i < sizeof(salt); i++)    {        mac_salt[i] ^= 0x3a;    }#endif
    int reserve = IV_SIZE;      //校验码长度,PC端每4096字节有48字节#ifndef NO_USE_HMAC_SHA1    reserve += HMAC_SHA1_SIZE;#endif    reserve = ((reserve % AES_BLOCK_SIZE) == 0) ? reserve : ((reserve / AES_BLOCK_SIZE) + 1) * AES_BLOCK_SIZE;
    unsigned char key[KEY_SIZE] = { 0 };    unsigned char mac_key[KEY_SIZE] = { 0 };
    OpenSSL_add_all_algorithms();    PKCS5_PBKDF2_HMAC_SHA1((const char*)pass, sizeof(pass), salt, sizeof(salt), DEFAULT_ITER, sizeof(key), key);#ifndef NO_USE_HMAC_SHA1    PKCS5_PBKDF2_HMAC_SHA1((const char*)key, sizeof(key), mac_salt, sizeof(mac_salt), 2, sizeof(mac_key), mac_key);#endif
    unsigned char* pTemp = pDbBuffer;    unsigned char pDecryptPerPageBuffer[DEFAULT_PAGESIZE];    int nPage = 1;    int offset = 16;    while (pTemp < pDbBuffer + nFileSize)    {        printf("解密数据页:%d/%d \n", nPage, nFileSize / DEFAULT_PAGESIZE);
#ifndef NO_USE_HMAC_SHA1        unsigned char hash_mac[HMAC_SHA1_SIZE] = { 0 };        unsigned int hash_len = 0;        HMAC_CTX hctx;        HMAC_CTX_init(&hctx);        HMAC_Init_ex(&hctx, mac_key, sizeof(mac_key), EVP_sha1(), NULL);        HMAC_Update(&hctx, pTemp + offset, DEFAULT_PAGESIZE - reserve - offset + IV_SIZE);        HMAC_Update(&hctx, (const unsigned char*)& nPage, sizeof(nPage));        HMAC_Final(&hctx, hash_mac, &hash_len);        HMAC_CTX_cleanup(&hctx);        if (0 != memcmp(hash_mac, pTemp + DEFAULT_PAGESIZE - reserve + IV_SIZE, sizeof(hash_mac)))        {            printf("\n 哈希值错误! \n");            getchar();            return 0;        }#endif        //        if (nPage == 1)        {            memcpy(pDecryptPerPageBuffer, SQLITE_FILE_HEADER, offset);        }
        EVP_CIPHER_CTX* ectx = EVP_CIPHER_CTX_new();        EVP_CipherInit_ex(ectx, EVP_get_cipherbyname("aes-256-cbc"), NULL, NULL, NULL, 0);        EVP_CIPHER_CTX_set_padding(ectx, 0);        EVP_CipherInit_ex(ectx, NULL, NULL, key, pTemp + (DEFAULT_PAGESIZE - reserve), 0);
        int nDecryptLen = 0;        int nTotal = 0;        EVP_CipherUpdate(ectx, pDecryptPerPageBuffer + offset, &nDecryptLen, pTemp + offset, DEFAULT_PAGESIZE - reserve - offset);        nTotal = nDecryptLen;        EVP_CipherFinal_ex(ectx, pDecryptPerPageBuffer + offset + nDecryptLen, &nDecryptLen);        nTotal += nDecryptLen;        EVP_CIPHER_CTX_free(ectx);
        memcpy(pDecryptPerPageBuffer + DEFAULT_PAGESIZE - reserve, pTemp + DEFAULT_PAGESIZE - reserve, reserve);        char decFile[1024] = { 0 };        sprintf_s(decFile, "dec_%s", dbfilename);        FILE * fp;        fopen_s(&fp, decFile, "ab+");        {            fwrite(pDecryptPerPageBuffer, 1, DEFAULT_PAGESIZE, fp);            fclose(fp);        }
        nPage++;        offset = 0;        pTemp += DEFAULT_PAGESIZE;    }    printf("\n 解密成功! \n");    return 0;}