劫持微信聊天记录并分析还原 —— 解密数据库（二） - ToB企服应用市场:ToB评测及商务社交产业平台

# -*- coding: utf-8 -*-#
# -------------------------------------------------------------------------------
# Name: decryption.py
# Description:
# Author: Rainbow
# Date: 2024/11/05
# 微信数据库采用的加密算法是256位的AES-CBC。数据库的默认的页大小是4096字节即4KB，其中每一个页都是被单独加解密的。
# 加密文件的每一个页都有一个随机的初始化向量，它被保存在每一页的末尾。
# 加密文件的每一页都存有着消息认证码，算法使用的是HMAC-SHA1（安卓数据库使用的是SHA512）。它也被保存在每一页的末尾。
# 每一个数据库文件的开头16字节都保存了一段唯一且随机的盐值，作为HMAC的验证和数据的解密。
# 为了保证数据部分长度是16字节即AES块大小的整倍数，每一页的末尾将填充一段空字节，使得保留字段的长度为48字节。
# 综上，加密文件结构为第一页4KB数据前16字节为盐值，紧接着4032字节数据，再加上16字节IV和20字节HMAC以及12字节空字节；而后的页均是4048字节长度的加密数据段和48字节的保留段。
# -------------------------------------------------------------------------------
import hmac
import hashlib
import os
from typing import Union, List
from Cryptodome.Cipher import AES
# from Crypto.Cipher import AES # 如果上面的导入失败，可以尝试使用这个
from .utils import wx_core_error, wx_core_loger
SQLITE_FILE_HEADER = "SQLite format 3\x00" # SQLite文件头
KEY_SIZE = 32
DEFAULT_PAGESIZE = 4096
# 通过密钥解密数据库
@wx_core_error
def decrypt(key: str, db_path: str, out_path: str):
"""
通过密钥解密数据库
:param key: 密钥 64位16进制字符串
:param db_path: 待解密的数据库路径(必须是文件)
:param out_path: 解密后的数据库输出路径(必须是文件)
:return:
"""
if not os.path.exists(db_path) or not os.path.isfile(db_path):
return False, f"[-] db_path:'{db_path}' File not found!"
if not os.path.exists(os.path.dirname(out_path)):
return False, f"[-] out_path:'{out_path}' File not found!"
if len(key) != 64:
return False, f"[-] key:'{key}' Len Error!"
password = bytes.fromhex(key.strip())
try:
with open(db_path, "rb") as file:
blist = file.read()
except Exception as e:
return False, f"[-] db_path:'{db_path}' {e}!"
salt = blist[:16]
first = blist[16:4096]
if len(salt) != 16:
return False, f"[-] db_path:'{db_path}' File Error!"
mac_salt = bytes([(salt[i] ^ 58) for i in range(16)])
byteHmac = hashlib.pbkdf2_hmac("sha1", password, salt, 64000, KEY_SIZE)
mac_key = hashlib.pbkdf2_hmac("sha1", byteHmac, mac_salt, 2, KEY_SIZE)
hash_mac = hmac.new(mac_key, blist[16:4064], hashlib.sha1)
hash_mac.update(b'\x01\x00\x00\x00')
if hash_mac.digest() != first[-32:-12]:
return False, f"[-] Key Error! (key:'{key}'; db_path:'{db_path}'; out_path:'{out_path}' )"
with open(out_path, "wb") as deFile:
deFile.write(SQLITE_FILE_HEADER.encode())
for i in range(0, len(blist), 4096):
tblist = blist[i:i + 4096] if i > 0 else blist[16:i + 4096]
deFile.write(AES.new(byteHmac, AES.MODE_CBC, tblist[-48:-32]).decrypt(tblist[:-48]))
deFile.write(tblist[-48:])
return True, [db_path, out_path, key]
@wx_core_error
def batch_decrypt(key: str, db_path: Union[str, List[str]], out_path: str, is_print: bool = False):
"""
批量解密数据库
:param key: 密钥 64位16进制字符串
:param db_path: 待解密的数据库路径(文件或文件夹)
:param out_path: 解密后的数据库输出路径(文件夹)
:param is_logging: 是否打印日志
:return: (bool, [[input_db_path, output_db_path, key],...])
"""
if not isinstance(key, str) or not isinstance(out_path, str) or not os.path.exists(out_path) or len(key) != 64:
error = f"[-] (key:'{key}' or out_path:'{out_path}') Error!"
wx_core_loger.error(error, exc_info=True)
return False, error
process_list = []
if isinstance(db_path, str):
if not os.path.exists(db_path):
error = f"[-] db_path:'{db_path}' not found!"
wx_core_loger.error(error, exc_info=True)
return False, error
if os.path.isfile(db_path):
inpath = db_path
outpath = os.path.join(out_path, 'de_' + os.path.basename(db_path))
process_list.append([key, inpath, outpath])
elif os.path.isdir(db_path):
for root, dirs, files in os.walk(db_path):
for file in files:
inpath = os.path.join(root, file)
rel = os.path.relpath(root, db_path)
outpath = os.path.join(out_path, rel, 'de_' + file)
if not os.path.exists(os.path.dirname(outpath)):
os.makedirs(os.path.dirname(outpath))
process_list.append([key, inpath, outpath])
else:
error = f"[-] db_path:'{db_path}' Error "
wx_core_loger.error(error, exc_info=True)
return False, error
elif isinstance(db_path, list):
rt_path = os.path.commonprefix(db_path)
if not os.path.exists(rt_path):
rt_path = os.path.dirname(rt_path)
for inpath in db_path:
if not os.path.exists(inpath):
error = f"[-] db_path:'{db_path}' not found!"
wx_core_loger.error(error, exc_info=True)
return False, error
inpath = os.path.normpath(inpath)
rel = os.path.relpath(os.path.dirname(inpath), rt_path)
outpath = os.path.join(out_path, rel, 'de_' + os.path.basename(inpath))
if not os.path.exists(os.path.dirname(outpath)):
os.makedirs(os.path.dirname(outpath))
process_list.append([key, inpath, outpath])
else:
error = f"[-] db_path:'{db_path}' Error "
wx_core_loger.error(error, exc_info=True)
return False, error
result = []
for i in process_list:
result.append(decrypt(*i)) # 解密
# 删除空文件夹
for root, dirs, files in os.walk(out_path, topdown=False):
for dir in dirs:
if not os.listdir(os.path.join(root, dir)):
os.rmdir(os.path.join(root, dir))
if is_print:
print("=" * 32)
success_count = 0
fail_count = 0
for code, ret in result:
if code == False:
print(ret)
fail_count += 1
else:
print(f'[+] "{ret[0]}" -> "{ret[1]}"')
success_count += 1
print("-" * 32)
print(f"[+] 共 {len(result)} 个文件, 成功 {success_count} 个, 失败 {fail_count} 个")
print("=" * 32)
return True, result

复制代码