Revert "fix(decrypt): 修复数据库原始密钥解密与设备绑定提示"

This reverts commit bcd8f67c25.
2026-06-18 15:54:08 +08:00 · 2026-03-24 12:14:18 +08:00
parent dc7ac0a5e4
commit f5f3e85e31
5 changed files with 133 additions and 467 deletions
@@ -14,12 +14,7 @@ from ..app_paths import get_output_databases_dir
 from ..logging_config import get_logger
 from ..path_fix import PathFixRoute
 from ..key_store import upsert_account_keys_in_store
-from ..wechat_decrypt import (
-    WeChatDatabaseDecryptor,
-    build_decrypt_result_message,
-    decrypt_wechat_databases,
-    scan_account_databases_from_path,
-)
+from ..wechat_decrypt import WeChatDatabaseDecryptor, decrypt_wechat_databases, scan_account_databases_from_path

 logger = get_logger(__name__)

@@ -81,7 +76,6 @@ async def decrypt_databases(request: DecryptRequest):
            "message": results["message"],
            "processed_files": results["processed_files"],
            "failed_files": results["failed_files"],
-            "failure_details": results.get("failure_details", []),
            "account_results": results.get("account_results", {}),
        }

@@ -165,7 +159,6 @@ async def decrypt_databases_stream(
        fail_count = 0
        processed_files: list[str] = []
        failed_files: list[str] = []
-        failure_details: list[dict] = []
        account_results: dict = {}
        overall_current = 0

@@ -188,7 +181,6 @@ async def decrypt_databases_stream(
            account_success = 0
            account_processed: list[str] = []
            account_failed: list[str] = []
-            account_failure_details: list[dict] = []

            for db_info in dbs:
                if await request.is_disconnected():
@@ -240,20 +232,11 @@ async def decrypt_databases_stream(
                    status = "success"
                    msg = "解密成功"
                else:
-                    failure_detail = {
-                        "account": account,
-                        "file": db_path,
-                        "name": db_name,
-                        "code": str(decryptor.last_error_code or "").strip(),
-                        "reason": str(decryptor.last_error_message or "").strip() or "解密失败",
-                    }
                    account_failed.append(db_path)
-                    account_failure_details.append(failure_detail)
                    failed_files.append(db_path)
-                    failure_details.append(failure_detail)
                    fail_count += 1
                    status = "fail"
-                    msg = failure_detail["reason"]
+                    msg = "解密失败"

                yield _sse(
                    {
@@ -278,7 +261,6 @@ async def decrypt_databases_stream(
                "output_dir": str(account_output_dir),
                "processed_files": account_processed,
                "failed_files": account_failed,
-                "failure_details": account_failure_details,
            }

            # Build cache table (keep behavior consistent with the POST endpoint).
@@ -325,15 +307,9 @@ async def decrypt_databases_stream(
            "success_count": success_count,
            "failure_count": total_databases - success_count,
            "output_directory": str(base_output_dir.absolute()),
-            "message": build_decrypt_result_message(
-                total_databases=total_databases,
-                success_count=success_count,
-                failed_count=total_databases - success_count,
-                failure_details=failure_details,
-            ),
+            "message": f"解密完成: 成功 {success_count}/{total_databases}",
            "processed_files": processed_files,
            "failed_files": failed_files,
-            "failure_details": failure_details,
            "account_results": account_results,
        }

@@ -13,12 +13,12 @@ import hashlib
 import hmac
 import os
 import json
-import shutil
-import tempfile
 from pathlib import Path

 from cryptography.hazmat.backends import default_backend
+from cryptography.hazmat.primitives import hashes
 from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
+from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC

 from .app_paths import get_output_databases_dir

@@ -26,94 +26,6 @@ from .app_paths import get_output_databases_dir

 # SQLite文件头
 SQLITE_HEADER = b"SQLite format 3\x00"
-PAGE_SIZE = 4096
-KEY_SIZE = 32
-SALT_SIZE = 16
-IV_SIZE = 16
-HMAC_SIZE = 64
-RESERVE_SIZE = 80
-KEY_MISMATCH_GUIDANCE = (
-    "请在当前设备登录该账号后重新获取密钥；"
-    "如果聊天记录是从另一台设备复制过来的，当前设备通常无法获取原设备对应的密钥。"
-)
-
-
-def _derive_mac_key(raw_key: bytes, salt: bytes) -> bytes:
-    mac_salt = bytes(b ^ 0x3A for b in salt)
-    return hashlib.pbkdf2_hmac("sha512", raw_key, mac_salt, 2, dklen=KEY_SIZE)
-
-
-def _compute_page_hmac(mac_key: bytes, page: bytes, page_num: int) -> bytes:
-    offset = SALT_SIZE if page_num == 1 else 0
-    data_end = PAGE_SIZE - RESERVE_SIZE + IV_SIZE
-    mac = hmac.new(mac_key, digestmod=hashlib.sha512)
-    mac.update(page[offset:data_end])
-    mac.update(page_num.to_bytes(4, "little"))
-    return mac.digest()
-
-
-def _decrypt_page(raw_key: bytes, page: bytes, page_num: int) -> bytes:
-    iv = page[PAGE_SIZE - RESERVE_SIZE : PAGE_SIZE - RESERVE_SIZE + IV_SIZE]
-    offset = SALT_SIZE if page_num == 1 else 0
-    encrypted = page[offset : PAGE_SIZE - RESERVE_SIZE]
-
-    cipher = Cipher(
-        algorithms.AES(raw_key),
-        modes.CBC(iv),
-        backend=default_backend(),
-    )
-    decryptor = cipher.decryptor()
-    decrypted = decryptor.update(encrypted) + decryptor.finalize()
-
-    if page_num == 1:
-        return SQLITE_HEADER + decrypted + (b"\x00" * RESERVE_SIZE)
-    return decrypted + (b"\x00" * RESERVE_SIZE)
-
-
-def _failure_matches_key_mismatch(detail: dict | None) -> bool:
-    if not isinstance(detail, dict):
-        return False
-    code = str(detail.get("code") or "").strip().lower()
-    reason = str(detail.get("reason") or "").strip()
-    if code == "key_mismatch":
-        return True
-    return ("密钥" in reason and "不匹配" in reason) or ("当前数据库密钥不正确" in reason)
-
-
-def build_decrypt_result_message(
-    total_databases: int,
-    success_count: int,
-    failed_count: int,
-    failure_details: list[dict] | None = None,
-) -> str:
-    total = max(int(total_databases or 0), 0)
-    success = max(int(success_count or 0), 0)
-    failed = max(int(failed_count or 0), 0)
-    details = list(failure_details or [])
-
-    if total == 0:
-        return "未找到可解密的数据库文件"
-
-    if failed == 0:
-        return f"解密完成: 成功 {success}/{total}"
-
-    key_mismatch_count = sum(1 for item in details if _failure_matches_key_mismatch(item))
-
-    if success == 0 and failed == total:
-        if key_mismatch_count == failed:
-            return (
-                f"解密失败：当前数据库密钥不正确，或该密钥不属于当前账号/当前设备（0/{total} 成功）。"
-                + KEY_MISMATCH_GUIDANCE
-            )
-        return f"解密失败：0/{total} 个数据库解密成功，请检查密钥、账号与数据库路径是否匹配。"
-
-    if key_mismatch_count > 0:
-        return (
-            f"解密完成：成功 {success}/{total}，失败 {failed}/{total}。"
-            "失败文件中包含密钥不匹配的数据库，请确认使用的是当前账号在当前设备上的密钥。"
-        )
-
-    return f"解密完成：成功 {success}/{total}，失败 {failed}/{total}。"


 def _normalize_account_name(name: str) -> str:
@@ -309,123 +221,153 @@ class WeChatDatabaseDecryptor:
            self.key_bytes = bytes.fromhex(key_hex)
        except ValueError:
            raise ValueError("密钥必须是有效的十六进制字符串")
-        self.last_error_code = ""
-        self.last_error_message = ""
-
-    def _set_last_error(self, code: str, message: str) -> None:
-        self.last_error_code = str(code or "").strip()
-        self.last_error_message = str(message or "").strip()
-
-    def _clear_last_error(self) -> None:
-        self.last_error_code = ""
-        self.last_error_message = ""
    
    def decrypt_database(self, db_path: str, output_path: str) -> bool:
        """解密微信4.x版本数据库

-        这里传入的 key 已经是从微信进程内存提取出的 raw enc_key，
-        不是 SQLCipher 的口令，因此不能再做一轮 PBKDF2。
+        使用SQLCipher 4.0参数:
+        - PBKDF2-SHA512, 256000轮迭代
+        - AES-256-CBC加密
+        - HMAC-SHA512验证
+        - 页面大小4096字节
        """
        from .logging_config import get_logger
        logger = get_logger(__name__)

        logger.info(f"开始解密数据库: {db_path}")
-
-        tmp_output_path = ""
-        self._clear_last_error()
+        
        try:
-            file_size = os.path.getsize(db_path)
-            logger.info(f"读取文件大小: {file_size} bytes")
+            with open(db_path, 'rb') as f:
+                encrypted_data = f.read()
+            
+            logger.info(f"读取文件大小: {len(encrypted_data)} bytes")

-            if file_size < PAGE_SIZE:
-                message = f"数据库文件过小，无法解密: {db_path}"
-                self._set_last_error("file_too_small", message)
-                logger.warning(message)
-                return False
-
-            output_dir = Path(output_path).parent
-            output_dir.mkdir(parents=True, exist_ok=True)
-
-            with open(db_path, "rb") as source:
-                page1 = source.read(PAGE_SIZE)
-
-            if len(page1) < PAGE_SIZE:
-                message = f"数据库首页大小不足，无法解密: {db_path}"
-                self._set_last_error("page_too_small", message)
-                logger.warning(message)
+            if len(encrypted_data) < 4096:
+                logger.warning(f"文件太小，跳过解密: {db_path}")
                return False

            # 检查是否已经是解密的数据库
-            if page1.startswith(SQLITE_HEADER):
+            if encrypted_data.startswith(SQLITE_HEADER):
                logger.info(f"文件已是SQLite格式，直接复制: {db_path}")
-                fd, tmp_output_path = tempfile.mkstemp(
-                    prefix=f".{Path(output_path).name}.",
-                    suffix=".tmp",
-                    dir=str(output_dir),
-                )
-                os.close(fd)
-                with open(db_path, "rb") as src, open(tmp_output_path, "wb") as dst:
-                    shutil.copyfileobj(src, dst, length=1024 * 1024)
-                os.replace(tmp_output_path, output_path)
-                tmp_output_path = ""
+                with open(output_path, 'wb') as f:
+                    f.write(encrypted_data)
                return True
-
-            salt = page1[:SALT_SIZE]
-            mac_key = _derive_mac_key(self.key_bytes, salt)
-            expected_page1_hmac = _compute_page_hmac(mac_key, page1, 1)
-            stored_page1_hmac = page1[PAGE_SIZE - HMAC_SIZE : PAGE_SIZE]
-            if stored_page1_hmac != expected_page1_hmac:
-                message = f"当前数据库密钥不正确，或该密钥不属于当前账号/当前设备: {db_path}"
-                self._set_last_error("key_mismatch", message)
-                logger.error(f"页面 1 HMAC验证失败，密钥与数据库不匹配: {db_path}")
-                return False
-
-            total_pages = (file_size + PAGE_SIZE - 1) // PAGE_SIZE
-            successful_pages = 0
-            fd, tmp_output_path = tempfile.mkstemp(
-                prefix=f".{Path(output_path).name}.",
-                suffix=".tmp",
-                dir=str(output_dir),
+            
+            # 提取salt (前16字节)
+            salt = encrypted_data[:16]
+            
+            # 计算mac_salt (salt XOR 0x3a)
+            mac_salt = bytes(b ^ 0x3a for b in salt)
+            
+            # 使用PBKDF2-SHA512派生密钥
+            kdf = PBKDF2HMAC(
+                algorithm=hashes.SHA512(),
+                length=32,
+                salt=salt,
+                iterations=256000,
+                backend=default_backend()
            )
-            os.close(fd)
-
-            with open(db_path, "rb") as source, open(tmp_output_path, "wb") as target:
-                for page_num in range(1, total_pages + 1):
-                    page = source.read(PAGE_SIZE)
-                    if not page:
-                        break
-                    if len(page) < PAGE_SIZE:
-                        logger.warning(f"页面 {page_num} 大小不足: {len(page)} bytes，自动补齐到 {PAGE_SIZE} bytes")
-                        page = page + (b"\x00" * (PAGE_SIZE - len(page)))
-
-                    stored_hmac = page[PAGE_SIZE - HMAC_SIZE : PAGE_SIZE]
-                    expected_hmac = _compute_page_hmac(mac_key, page, page_num)
-                    if stored_hmac != expected_hmac:
-                        message = f"数据库校验失败，文件可能损坏或密钥不匹配: {db_path}"
-                        self._set_last_error("page_hmac_mismatch", message)
-                        logger.error(f"页面 {page_num} HMAC验证失败，终止解密: {db_path}")
-                        return False
-
-                    target.write(_decrypt_page(self.key_bytes, page, page_num))
+            derived_key = kdf.derive(self.key_bytes)
+            
+            # 派生MAC密钥
+            mac_kdf = PBKDF2HMAC(
+                algorithm=hashes.SHA512(),
+                length=32,
+                salt=mac_salt,
+                iterations=2,
+                backend=default_backend()
+            )
+            mac_key = mac_kdf.derive(derived_key)
+            
+            # 解密数据
+            decrypted_data = bytearray()
+            decrypted_data.extend(SQLITE_HEADER)
+            
+            page_size = 4096
+            iv_size = 16
+            hmac_size = 64  # SHA512的HMAC是64字节
+            
+            # 计算保留区域大小 (对齐到AES块大小)
+            reserve_size = iv_size + hmac_size
+            if reserve_size % 16 != 0:
+                reserve_size = ((reserve_size // 16) + 1) * 16
+            
+            total_pages = len(encrypted_data) // page_size
+            successful_pages = 0
+            failed_pages = 0
+            
+            # 逐页解密
+            for cur_page in range(total_pages):
+                start = cur_page * page_size
+                end = start + page_size
+                page = encrypted_data[start:end]
+                
+                page_num = cur_page + 1  # 页面编号从1开始
+                
+                if len(page) < page_size:
+                    logger.warning(f"页面 {page_num} 大小不足: {len(page)} bytes")
+                    break
+                
+                # 确定偏移量：第一页(cur_page == 0)需要跳过salt
+                offset = 16 if cur_page == 0 else 0  # SALT_SIZE = 16
+                
+                # 提取存储的HMAC
+                hmac_start = page_size - reserve_size + iv_size
+                hmac_end = hmac_start + hmac_size
+                stored_hmac = page[hmac_start:hmac_end]
+                
+                # 按照wechat-dump-rs的方式验证HMAC
+                data_end = page_size - reserve_size + iv_size
+                hmac_data = page[offset:data_end]
+                
+                # 分步计算HMAC：先更新数据，再更新页面编号
+                mac = hmac.new(mac_key, digestmod=hashlib.sha512)
+                mac.update(hmac_data)  # 包含加密数据+IV
+                mac.update(page_num.to_bytes(4, 'little'))  # 页面编号(小端序)
+                expected_hmac = mac.digest()
+                
+                if stored_hmac != expected_hmac:
+                    logger.warning(f"页面 {page_num} HMAC验证失败")
+                    failed_pages += 1
+                    continue
+                
+                # 提取IV和加密数据用于AES解密
+                iv = page[page_size - reserve_size:page_size - reserve_size + iv_size]
+                encrypted_page = page[offset:page_size - reserve_size]
+                
+                # AES-CBC解密
+                try:
+                    cipher = Cipher(
+                        algorithms.AES(derived_key),
+                        modes.CBC(iv),
+                        backend=default_backend()
+                    )
+                    decryptor = cipher.decryptor()
+                    decrypted_page = decryptor.update(encrypted_page) + decryptor.finalize()
+                    
+                    # 按照wechat-dump-rs的方式重组页面数据
+                    decrypted_data.extend(decrypted_page)
+                    decrypted_data.extend(page[page_size - reserve_size:])  # 保留区域
+                    
                    successful_pages += 1
+                
+                except Exception as e:
+                    logger.error(f"页面 {page_num} AES解密失败: {e}")
+                    failed_pages += 1
+                    continue

-            logger.info(f"解密完成: 成功 {successful_pages} 页, 失败 0 页")
-            os.replace(tmp_output_path, output_path)
-            tmp_output_path = ""
-            logger.info(f"解密文件大小: {os.path.getsize(output_path)} bytes")
-            self._clear_last_error()
+            logger.info(f"解密完成: 成功 {successful_pages} 页, 失败 {failed_pages} 页")
+
+            # 写入解密后的文件
+            with open(output_path, 'wb') as f:
+                f.write(decrypted_data)
+
+            logger.info(f"解密文件大小: {len(decrypted_data)} bytes")
            return True

        except Exception as e:
-            self._set_last_error("exception", f"解密过程中发生异常: {e}")
            logger.error(f"解密失败: {db_path}, 错误: {e}")
            return False
-        finally:
-            if tmp_output_path:
-                try:
-                    os.remove(tmp_output_path)
-                except OSError:
-                    pass

 def decrypt_wechat_databases(db_storage_path: str = None, key: str = None) -> dict:
    """
@@ -550,7 +492,6 @@ def decrypt_wechat_databases(db_storage_path: str = None, key: str = None) -> di
    success_count = 0
    processed_files = []
    failed_files = []
-    failure_details = []
    account_results = {}

    for account_name, databases in account_databases.items():
@@ -582,7 +523,6 @@ def decrypt_wechat_databases(db_storage_path: str = None, key: str = None) -> di
        account_success = 0
        account_processed = []
        account_failed = []
-        account_failure_details = []

        for db_info in databases:
            db_path = db_info['path']
@@ -602,16 +542,7 @@ def decrypt_wechat_databases(db_storage_path: str = None, key: str = None) -> di
            else:
                account_failed.append(db_path)
                failed_files.append(db_path)
-                failure_detail = {
-                    "account": account_name,
-                    "file": db_path,
-                    "name": db_name,
-                    "code": str(decryptor.last_error_code or "").strip(),
-                    "reason": str(decryptor.last_error_message or "").strip() or "解密失败",
-                }
-                account_failure_details.append(failure_detail)
-                failure_details.append(failure_detail)
-                logger.error(f"解密失败: {account_name}/{db_name} reason={failure_detail['reason']}")
+                logger.error(f"解密失败: {account_name}/{db_name}")

        # 记录账号解密结果
        account_results[account_name] = {
@@ -620,8 +551,7 @@ def decrypt_wechat_databases(db_storage_path: str = None, key: str = None) -> di
            "failed": len(databases) - account_success,
            "output_dir": str(account_output_dir),
            "processed_files": account_processed,
-            "failed_files": account_failed,
-            "failure_details": account_failure_details,
+            "failed_files": account_failed
        }

        # 构建“会话最后一条消息”缓存表：把耗时挪到解密阶段，后续会话列表直接查表
@@ -645,23 +575,15 @@ def decrypt_wechat_databases(db_storage_path: str = None, key: str = None) -> di
        logger.info(f"账号 {account_name} 解密完成: 成功 {account_success}/{len(databases)}")

    # 返回结果
-    failed_count = total_databases - success_count
-    message = build_decrypt_result_message(
-        total_databases=total_databases,
-        success_count=success_count,
-        failed_count=failed_count,
-        failure_details=failure_details,
-    )
    result = {
        "status": "success" if success_count > 0 else "error",
-        "message": message,
+        "message": f"解密完成: 成功 {success_count}/{total_databases}",
        "total_databases": total_databases,
        "successful_count": success_count,
-        "failed_count": failed_count,
+        "failed_count": total_databases - success_count,
        "output_directory": str(base_output_dir.absolute()),
        "processed_files": processed_files,
        "failed_files": failed_files,
-        "failure_details": failure_details,
        "account_results": account_results,  # 新增：按账号的详细结果
        "detected_accounts": detected_accounts,
    }
@@ -669,9 +591,8 @@ def decrypt_wechat_databases(db_storage_path: str = None, key: str = None) -> di
    logger.info("=" * 60)
    logger.info("解密任务完成!")
    logger.info(f"成功: {success_count}/{total_databases}")
-    logger.info(f"失败: {failed_count}/{total_databases}")
+    logger.info(f"失败: {total_databases - success_count}/{total_databases}")
    logger.info(f"输出目录: {base_output_dir.absolute()}")
-    logger.info(f"结果说明: {message}")
    logger.info("=" * 60)

    return result