AES-GCM Encryption Script securely encrypts and decrypts text using AES-256 in Galois/Counter Mode.
AES-GCM Encryption Script: Overview- Purpose: - The script allows users to securely encrypt and decrypt text using the Advanced Encryption Standard (AES) in Galois/Counter Mode (GCM). - AES-GCM provides both confidentiality (encryption) and authenticity (authentication) for data.
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Components:
- Key Derivation: The user's password is used to derive a unique encryption key.
- Encryption: Plaintext is encrypted using AES-GCM with a random nonce.
- Decryption: Ciphertext is decrypted back to plaintext.
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Security Features:
- Key Strength: The script uses a 256-bit key derived from the user's password, which is considered secure.
- Nonce: A random nonce ensures that the same plaintext encrypted multiple times produces different ciphertexts.
- Authentication Tag: GCM provides integrity and authenticity by including an authentication tag with the ciphertext.
How to Use the Script:- Requirements: - Ensure you have Python installed on your system. - The cryptography library is required. Install it using pip install cryptography.
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Running the Script:
- Save the code snippet as a Python file (e.g., aes_gcm.py).
- Open a terminal or command prompt.
- Navigate to the directory containing the script.
- Run the script using python aes_gcm.py.
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Choose Operation:
- The script will prompt you to choose between encryption ('e') or decryption ('d').
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Encryption:
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If you choose encryption ('e'):
- Enter Password: *******
- Enter the plaintext you want to encrypt.
- The script will generate a random salt, derive a key from your password, and encrypt the data.
- It will display the base64-encoded encrypted text.
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Example:
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Do you want to (e)ncrypt or (d)ecrypt? (e/d): e Enter Password: ******* Enter text to encrypt: Hello, world! Encrypted text:
- Decryption:
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If you choose decryption ('d'):
- Enter Password: ******
- Enter the base64-encoded encrypted text.
- The script will decode the data, extract the components, derive the key, and decrypt the ciphertext.
- It will display the original plaintext.
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Example:
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Do you want to (e)ncrypt or (d)ecrypt? (e/d): d Enter Password: ****** Enter text to decrypt: Decrypted text: Hello, world!
- Repeat or Exit:
- After each operation, the script will ask if you want to perform another operation.
- Type 'y' to continue or 'n' to exit.
Security Assessment:- Confidentiality: AES-GCM provides strong confidentiality due to the 256-bit key length.
- Integrity/Authenticity: The authentication tag ensures data integrity and authenticity.
- Password Security: The security depends on the strength of your password. Use a strong, unique password.
- Nonce Reuse: Ensures nonces are never reused for different messages.
Remember to keep your password secure and avoid sharing it. Overall, this script provides a good balance of security and usability for encrypting sensitive data.
Feel free to share it with others! 😊