diff --git a/ENCRYPTION_HANDLING.md b/ENCRYPTION_HANDLING.md new file mode 100644 index 000000000..1e5113a2c --- /dev/null +++ b/ENCRYPTION_HANDLING.md @@ -0,0 +1,148 @@ +# Netmiko Encryption Handling + +This document describes the encryption mechanisms available in Netmiko for handling sensitive data in configuration files. These mechanisms are generally intended for use with `~/.netmiko.yml` and Netmiko Tools. + +## Overview + +Netmiko provides built-in encryption capabilities to secure sensitive data (like passwords) in your Netmiko Tools YAML configuration files. The encryption system is flexible and supports multiple encryption types. + +## Configuration + +### Basic Setup + +Encryption is configured in the `~/.netmiko.yml` file using the `__meta__` field: + +```yaml +__meta__: + encryption: true + encryption_type: fernet # or aes128 +``` + +The two supported encryption types are: +- `fernet` (recommended) +- `aes128` + +### Encryption Key + +The encryption key is read from the environment variable `NETMIKO_TOOLS_KEY`. This should be a secure, randomly-generated key appropriate for the chosen encryption type. + +```bash +# Example of setting the encryption key +export NETMIKO_TOOLS_KEY="your-secure-key-here" +``` + +## Using Encryption + +### Encrypted Values in YAML + +When encryption is enabled, Netmiko looks for fields that start with `__encrypt__`. For example: + +```yaml +arista1: + device_type: arista_eos + host: arista1.domain.com + username: pyclass + password: > + __encrypt__ifcs7SWOUER4m1K3ZEZYlw==:Z0FBQUFBQm5CQ9lrdV9BVS0xOWxYelF1Yml + zV3hBcnF4am1SWjRYNnVSRGdBb1FPVmJ2Q2EzX1RjTWxYMVVMdlBZSXVqYWVqUVNASXNRO + FBpR1MxRTkxN2J0NWxVeZNKT0E9PQ== +``` + +### Encryption Functions + +#### Encrypting Values + +To encrypt a value, use the `encrypt_value` function: + +```python +def encrypt_value(value: str, key: bytes, encryption_type: str) -> str: + """ + Encrypt a value using the specified encryption type. + + Args: + value: The string to encrypt + key: Encryption key as bytes + encryption_type: Either 'fernet' or 'aes128' + + Returns: + Encrypted string with '__encrypt__' prefix + """ +``` + +#### Decrypting Values + +To decrypt a value, use the `decrypt_value` function: + +```python +def decrypt_value(encrypted_value: str, key: bytes, encryption_type: str) -> str: + """ + Decrypt a value using the specified encryption type. + + Args: + encrypted_value: The encrypted string (including '__encrypt__' prefix) + key: Encryption key as bytes + encryption_type: Either 'fernet' or 'aes128' + + Returns: + Decrypted string + """ +``` + +#### Getting the Encryption Key + +To retrieve the encryption key from the environment: + +```python +def get_encryption_key() -> bytes: + """ + Retrieve the encryption key from NETMIKO_TOOLS_KEY environment variable. + + Returns: + Encryption key as bytes + """ +``` + +## Example Usage + +Here's a complete example of how to use encryption in your code: + +```python +from netmiko.encryption_handling import encrypt_value, get_encryption_key +from netmiko.encryption_handling import decrypt_value + +# Get the encryption key from environment +key = get_encryption_key() + +# Encrypt a password +password = "my_secure_password" +encrypted_password = encrypt_value(password, key, "fernet") + +# The encrypted password can now be stored in your YAML file +# It will automatically be decrypted when Netmiko Tools reads the +# file (assuming you have properly set the '__meta__' fields +``` + +Alternatively, you can decrypt the value by calling + +```python +clear_value = decrypt_value(encrypted_value, key, encryption_type="fernet) +``` + +Or you can create a simple function to decrypt all of the fields in the YAML +file dynamically (by looking for any fields that start with `__encrypt__`). + +Netmiko's 'encryption_handling.py' implements this using the 'decrypt_config' +function, but this function is a specific to Netmiko Tools' .netmiko.yml format +(i.e. it will need modified if you want to use it in a more generic context). + +## Implementation Notes + +1. Encryption is processed transparently when Netmiko Tools reads the YAML file +2. Only fields prefixed with `__encrypt__` are processed for decryption +3. The encryption type is determined by the `__meta__` section + +## Security Considerations + +1. Store the `NETMIKO_TOOLS_KEY` securely and never commit it to version control +2. Fernet encryption is recommended over AES128 as it includes additional security features +3. Encrypted values in YAML files should still be treated as sensitive data