sberbank-async-cryptography

Sberbank signature verification using async cryptography

The code of keys generation and message signing and signature verification is universal, it is not only Sberbank-compatible. You can use it for your own purposes. However there is a sberbank_tools module that consist sberbank-specific functions.

The repo is open for pull requests. The author will be glad to hear some good feedback from you.

Python version

Python version that has been used while coding is 3.8. Other versions has not been tested but they might work.

Installation

pip install -i sberbank_callback_async_cryptography

Flask example

import os
from dotenv import load_dotenv

from flask import request
from flask_restful import Resource
from sb_async_cryptography.sberbank_tools import verify_signature, params_get_checksum
from sb_async_cryptography.signature import public_key_import_from_x509_certificate_file

load_dotenv()
SBERBANK_PUBLIC_KEY_FILE = os.getenv('SBERBANK_PUBLIC_KEY_FILE')
pub_key = public_key_import_from_x509_certificate_file(SBERBANK_PUBLIC_KEY_FILE)


class Notification(Resource):

    def get(self):
        """Status change notification from Sberbank"""
        params = request.args
        signature = params_get_checksum(params)
        if not verify_signature(pub_key, signature, params):
            return {"errors": "Signature verification failed."}, 400

        # some other code here

FastAPI example

import os
from dotenv import load_dotenv

from fastapi import Request
from sb_async_cryptography.sberbank_tools import verify_signature, params_get_checksum
from sb_async_cryptography.signature import public_key_import_from_x509_certificate_file
from starlette.responses import JSONResponse

load_dotenv()
SBERBANK_PUBLIC_KEY_FILE = os.getenv('SBERBANK_PUBLIC_KEY_FILE')
pub_key = public_key_import_from_x509_certificate_file(SBERBANK_PUBLIC_KEY_FILE)


async def notification(request: Request):
    """Status change notification from Sberbank"""
    params = dict(request.query_params)
    signature = params_get_checksum(params)
    if not verify_signature(pub_key, signature, params):
        return JSONResponse(status_code=400, content={"errors": "Signature verification failed."})

    # some other code here