SafePickling

SafePickling is a python library that allows you to sign and verify python pickles.

graph LR
    subgraph Server
        A[Object]:::object -->B{Pickle and sign}:::cryptography
        C[Key]:::storage --> B
        B --> pik2[signature] --> D(Server):::network
        B --> pik1[pickle] --> D
    end
    subgraph Client
        D ==> E(Client):::network
        E -->unpik2[signature]
        E -->unpik1[pickle] --> F{Sign}:::cryptography
        known[(Known keys)]:::storage --> F --> F
        F --> eq{Is equal?}
        unpik2 --> eq:::cryptography
        eq -->|Yes|unpik{{Unpickle}}:::cryptography --> Z[Object]:::object
        eq -->|No|Invalid(Invalid):::error
    end

    classDef network fill:#FFD666;
    classDef cryptography fill:#82FF66;
    classDef error fill:#FF6B66;
    classDef storage fill:#DE66FF;
    classDef object fill:#666EFF;

Installation

pip install safepickling

Usage Example

object = ExampleObject()

server = SafePickling() # Create a server instance
server.generate_key() # Generate a random key for the server
pickled_object = server.pickle(object) # Pickle the object and sign it

client = SafePickling() # Create a client instance
client.add_trusted_keys([server.key]) # Add the server's key to the client's trusted keys
unpickled_object = client.unpickle(pickled_object) # Unpickle the data while verifying it's signature with the server's key

Cryptography

Random provided by secrets.token_bytes

Hash comparison with hmac.compare_digest

Hashing done using hashlib.blake2b