{"id":9892,"library":"lightdsa","title":"LightDSA","description":"LightDSA (version 0.0.3) is a lightweight Python library providing Digital Signature Algorithm functionalities. Currently, it primarily supports the RSA algorithm for generating keys, signing data, and verifying signatures. Its development appears to be inactive since 2021, and new releases are infrequent.","status":"abandoned","version":"0.0.3","language":"en","source_language":"en","source_url":"https://github.com/serengil/LightDSA","tags":["digital signature","DSA","RSA","cryptography","security"],"install":[{"cmd":"pip install lightdsa","lang":"bash","label":"Install LightDSA"}],"dependencies":[{"reason":"Provides core cryptographic primitives for key generation, signing, and verification.","package":"pycryptodome"}],"imports":[{"symbol":"LightDSA","correct":"from lightdsa import LightDSA"}],"quickstart":{"code":"from lightdsa import LightDSA\n\n# 1. Generate keys\n# For RSA, key_size must be between 1024 and 4096 (inclusive)\n# and a multiple of 256.\ndsa = LightDSA(key_size=2048) # Default is 2048\nprivate_key_pem = dsa.private_key_to_pem().decode('utf-8')\npublic_key_pem = dsa.public_key_to_pem().decode('utf-8')\n\nprint(\"Private Key (PEM format):\")\nprint(private_key_pem)\nprint(\"\\nPublic Key (PEM format):\")\nprint(public_key_pem)\n\n# 2. Sign data\nmessage_to_sign = \"This is a secret message.\"\nsignature = dsa.sign(message_to_sign.encode('utf-8'))\n\nprint(f\"\\nMessage: {message_to_sign}\")\nprint(f\"Signature: {signature.hex()}\")\n\n# 3. Verify signature using the current object's keys\nis_valid = dsa.verify(message_to_sign.encode('utf-8'), signature)\nprint(f\"Signature valid: {is_valid}\")\n\n# You can also load keys from PEM strings into a new LightDSA instance\ndsa_loaded = LightDSA(key_size=2048) # key_size required for initialization\ndsa_loaded.load_public_key_from_pem(public_key_pem.encode('utf-8'))\ndsa_loaded.load_private_key_from_pem(private_key_pem.encode('utf-8')) # Optional for verification\n\nis_valid_loaded = dsa_loaded.verify(message_to_sign.encode('utf-8'), signature)\nprint(f\"Signature valid (loaded keys): {is_valid_loaded}\")","lang":"python","description":"This quickstart demonstrates how to generate RSA keys, sign a message, and verify the signature using the `LightDSA` class. It also shows how to load keys from PEM format."},"warnings":[{"fix":"Consider alternatives for actively maintained cryptographic libraries in production environments, such as `cryptography`.","message":"The LightDSA library appears to be unmaintained. The last commit on GitHub was in 2021, and the version 0.0.3 suggests early development. Users should be aware that it may not receive future updates or security fixes.","severity":"gotcha","affected_versions":"<=0.0.3"},{"fix":"Do not expect support for other DSA algorithms like ECDSA. If you require other signature types, use a more comprehensive library like `cryptography`.","message":"Despite its name, LightDSA currently only supports the RSA algorithm for digital signatures. The `key_size` parameter is specifically for RSA key lengths.","severity":"gotcha","affected_versions":"<=0.0.3"},{"fix":"Ensure `pycryptodome` is correctly installed: `pip install pycryptodome`. If you encounter build errors, consult `pycryptodome`'s documentation for platform-specific dependencies.","message":"LightDSA relies on the `pycryptodome` library. Incorrect or incomplete installation of `pycryptodome` (which might require C build tools on some systems) can lead to runtime errors.","severity":"gotcha","affected_versions":"<=0.0.3"}],"env_vars":null,"last_verified":"2026-04-17T00:00:00.000Z","next_check":"2026-07-16T00:00:00.000Z","problems":[{"fix":"Install the `pycryptodome` package: `pip install pycryptodome`.","cause":"The `lightdsa` library uses `pycryptodome` internally, which often exposes its modules under the `Crypto` namespace. This error indicates `pycryptodome` is not installed.","error":"ModuleNotFoundError: No module named 'Crypto'"},{"fix":"Convert your string data to bytes before passing it to `sign()` or `verify()`. For example, `my_string.encode('utf-8')`.","cause":"Cryptographic functions for signing and verification expect byte-like objects (e.g., `bytes`), not strings. You are likely passing a Python `str` directly.","error":"TypeError: object of type 'str' has no len()"}]}