auxlib.crypt

wrapper around PyCrypto cryptography library

Information sources:

• http://eli.thegreenplace.net/2010/06/25/aes-encryption-of-files-in-python-with-pycrypto/
• http://code.activestate.com/recipes/576980-authenticated-encryption-with-pycrypto/

auxlib.crypt.as_base64(content)

auxlib.crypt.from_base64(content)

auxlib.crypt.encrypt(secret_key, data)

auxlib.crypt.decrypt(secret_key, encryption_key_encrypted, encrypted_data)

auxlib.crypt.aes_encrypt(base64_encryption_key, data)

Encrypt data with AES-CBC and sign it with HMAC-SHA256

Parameters:

• base64_encryption_key (str) – a base64-encoded string containing an AES encryption key and HMAC signing key as generated by generate_encryption_key()
• data (str) – a byte string containing the data to be encrypted

Returns:

the encrypted data as a byte string with the HMAC signature appended to the end

Return type:

str

auxlib.crypt.aes_decrypt(base64_encryption_key, base64_data)

Verify HMAC-SHA256 signature and decrypt data with AES-CBC

Parameters:

• encryption_key (str) – a base64-encoded string containing an AES encryption key and HMAC signing key as generated by generate_encryption_key()
• data (str) – a byte string containing the data decrypted with an HMAC signing key appended to the end

Returns:

a byte string containing the data that was originally encrypted

Return type:

str

Raises:

AuthenticationError – when the HMAC-SHA256 signature authentication fails