SecureVault Class Documentation

The SecureVault class provides functionality for encrypting data, generating digital signatures, and working with encrypted files. It utilizes the sodium_crypto_secretbox encryption algorithm and the Firebase\JWT\JWT library for digital signature generation and verification.

Class Methods:

1. cipher(string $value, string $key): string

   • Encrypts the given string using the provided key.
   • Parameters:
     • $value (string): The string to be encrypted.
     • $key (string): The encryption key.
   • Returns:
     • Encrypted string.

2. deCipher(string $cipher, string $key): mixed

   • Decrypts the encrypted string and returns the original plaintext string.
   • Parameters:
     • $cipher (string): The encrypted string to be decrypted.
     • $key (string): The decryption key.
   • Returns:
     • The decrypted plaintext string or false if decryption fails.

3. retrieveJWTFromFile(string $data): string|bool

   • Retrieves the JWT (JSON Web Token) from the given file content.
   • Parameters:
     • $data (string): The content of the encrypted file.
   • Returns:
     • The JWT if found in the content, or false if not found.

4. fileDecipher(string $file, string $key): array|bool

   • Decrypts the content of an encrypted file and returns the deciphered data as an array.
   • Parameters:
     • $file (string): The path to the encrypted file.
     • $key (string): The decryption key.
   • Throws:
     • Exception if the file does not exist, has an invalid name format, or contains invalid JSON content.
   • Returns:
     • The deciphered data as an array if decryption and verification are successful, or false otherwise.

5. verifySignature(string $fileContent, string $jwt, string $secreteKey): bool

   • Verifies the digital signature of the file content using the provided JWT and secret key.
   • Parameters:
     • $fileContent (string): The content of the encrypted file.
     • $jwt (string): The JSON Web Token (JWT) to be verified.
     • $secreteKey (string): The secret key used for verification.
   • Returns:
     • True if the signature is valid, false otherwise.

6. generateSignature(string $data, string $key, array $extra = []): string

   • Generates a digital signature (JWT) for the given data using the provided key.
   • Parameters:
     • $data (string): The data to be signed.
     • $key (string): The key used for signing.
     • $extra (array): Additional data to include in the signature payload. (Optional)
   • Returns:
     • The generated digital signature (JWT) as a string.

7. encryptToFile(array $fileContent, string $key, string $dir = DIR, string $prefix = 'config_'): bool|int

   • Encrypts the provided file content, generates a digital signature, and writes it to a file.
   • Parameters:
     • $fileContent (array): The data to be encrypted and written to the file.
     • $key (string): The encryption key.
     • $dir (string): The directory where the encrypted file should be stored. (Optional)
     • $prefix (string): The prefix to be added to the file name. (Optional)
   • Throws:
     • Exception if the given directory is not a valid directory.
     • Exception if encryption or signature generation fails.
   • Returns:
     • The number of bytes written to the file on success, or false if an error occurs.

Additional Notes:

• The SecureVault class provides functionality for secure encryption, decryption, and file operations.
• It uses the sodium_crypto_secretbox algorithm for encryption, which is considered secure.
• Digital signatures (JWTs) are generated and verified using the HS256 algorithm from the Firebase\JWT\JWT library.
• Proper key management and secure storage of sensitive information (such as encryption keys and secret keys) are essential for maintaining the security of the encrypted data.
• Input validation and sanitization should be performed to prevent security vulnerabilities.
• It's recommended to follow secure coding practices and conduct security assessments to ensure the overall security of the application.

For more information, please refer to the class documentation and code comments.