不擅密码学，求Windows下批量逐个加密文件的高安全简易AES方案

Hey there! I get that you're not super familiar with cryptography, and you need a reliable way to batch encrypt files one by one on Windows—especially since TrueCrypt 7.1a's lack of command-line support forced you to look at clunky UI automation with AutoIt. Let's walk through your two main options (OpenSSL and PGP) that'll work for cloud storage and play nice with your planned app.

1. OpenSSL: Lightweight, Command-Line Friendly #

OpenSSL is a great pick if you want a simple, standardized encryption tool that’s easy to integrate into custom apps. It supports strong symmetric encryption (perfect for your use case) and works seamlessly in batch scripts.

Step 1: Set Up OpenSSL #

First, install OpenSSL on Windows and add its bin directory to your system PATH (so you can run openssl commands from anywhere).

Step 2: Batch Encryption Script #

Create a batch file (e.g., encrypt_files.bat) with this code—tweak the paths and settings to match your needs:

@echo off
setlocal enabledelayedexpansion

:: Configure your settings
set "ENCRYPT_ALGO=aes-256-cbc"  :: Use AES-256 (industry-standard strong encryption)
set "PASSWORD_FILE=secure_pass.txt"  :: Store your password here (lock this file down!)
set "SOURCE_FOLDER=C:\Your\Files\To\Encrypt"
set "DEST_FOLDER=C:\Encrypted\Files\For\Cloud"

:: Create destination folder if it doesn't exist
if not exist "%DEST_FOLDER%" mkdir "%DEST_FOLDER%"

:: Encrypt each file in the source folder
for %%f in ("%SOURCE_FOLDER%\*.*") do (
    echo Encrypting: "%%f"
    openssl enc -%ENCRYPT_ALGO% -salt -in "%%f" -out "%DEST_FOLDER%\%%~nf.enc" -pass file:"%PASSWORD_FILE%"
    
    :: Check if encryption succeeded
    if !errorlevel! equ 0 (
        echo ✓ Successfully encrypted to "%DEST_FOLDER%\%%~nf.enc"
    ) else (
        echo ✗ Failed to encrypt "%%f"
    )
)

echo Batch encryption finished!
endlocal

Key Notes for App Integration #

• Avoid hardcoding passwords: Use a password file with strict permissions (only your user account can read it) or prompt for a single password via stdin (replace -pass file:... with -pass stdin to enter once for all files).
• Integrate into your app: Most programming languages (C#, Python, JavaScript) have OpenSSL-compatible libraries (like BouncyCastle, pyOpenSSL) so your app can encrypt/decrypt files directly without calling external scripts. The .enc output uses a standard format that these libraries can parse.

2. PGP: Secure for Cloud & Flexible Permissions #

PGP (via GnuPG/Gpg4win) is ideal if you want asymmetric encryption—meaning you use a public key to encrypt files, and only your private key can decrypt them. This is safer for cloud storage because you never have to share a symmetric password.

Step 1: Set Up Gpg4win #

Install Gpg4win (the Windows port of GnuPG) and generate your own PGP key pair (follow the setup wizard to create a public/private key).

Step 2: Batch Encryption Script #

Create a batch file (e.g., pgp_encrypt.bat) with this code—replace the recipient key ID with your own public key ID:

@echo off
setlocal enabledelayedexpansion

:: Configure your settings
set "RECIPIENT_KEY=0x123456789ABCDEF"  :: Your PGP public key ID
set "SOURCE_FOLDER=C:\Your\Files\To\Encrypt"
set "DEST_FOLDER=C:\Encrypted\Files\For\Cloud"

if not exist "%DEST_FOLDER%" mkdir "%DEST_FOLDER%"

:: Encrypt each file with your public key
for %%f in ("%SOURCE_FOLDER%\*.*") do (
    echo Encrypting: "%%f"
    gpg --encrypt --recipient %RECIPIENT_KEY% --output "%DEST_FOLDER%\%%~nf.gpg" "%%f"
    
    if !errorlevel! equ 0 (
        echo ✓ Successfully encrypted to "%DEST_FOLDER%\%%~nf.gpg"
    ) else (
        echo ✗ Failed to encrypt "%%f"
    )
)

echo Batch encryption finished!
endlocal

Key Notes for App Integration #

• Symmetric option: If you don't need asymmetric encryption, use gpg --symmetric instead (similar to OpenSSL, but uses PGP's symmetric format).
• App integration: Use PGP libraries (like BouncyCastle, OpenPGP.js) to add encryption/decryption directly to your app. GnuPG also has a command-line interface you can call from your app if you prefer.
• Key management: Backup your private key securely—losing it means you can't decrypt your files!

3. Final Tips #

• Skip AutoIt + TrueCrypt: UI automation is unreliable (breaks if TrueCrypt's UI changes) and inefficient for batch tasks. Command-line tools are far more stable and easier to integrate into your app.
• Cloud safety: Always encrypt files before uploading to the cloud. For extra peace of mind, generate a SHA-256 hash of each encrypted file (use openssl sha256 "file.enc" or gpg --print-md sha256 "file.gpg") and store the hashes locally—your app can verify them later to ensure files weren't corrupted or tampered with.
• Stick to standard algorithms: Use AES-256 (for OpenSSL) or RSA-2048+/ECC (for PGP) to ensure your encryption is secure against modern threats.

内容的提问来源于stack exchange，提问作者Liquid Core