SignatureBasique.py

import hashlib
import datetime
from Errors import *
from RSA import encode_private


def sign(information, private_key):
    result = hashlib.sha256(information.encode())
    hash_value = result.digest()
    signature = encode_private(private_key, hash_value)
    return signature


class SignatureBasique:
    def __init__(self, information, private, certificat, type_chiffrement="SHA256"):
        print("Creation d'une signature")

        now = datetime.datetime.now()

        if certificat.get_date_fin_validite() < now:
            print("Erreur : certificat expiré")
            raise SignError("Erreur : certificat expiré")
        CRL = certificat.get_prestataire().get_liste_revocation()
        if certificat.get_ID() in CRL:
            print("Erreur : certificat revoqué")
            raise SignError("Erreur : certificat revoqué")

        if type_chiffrement != "SHA256":
            print("ATTENTION type de chiffrement " + type_chiffrement + " non supporté, utilisation de SHA256")
        self.__type_chiffrement = type_chiffrement
        self.__information = information
        self.__valeur_signature = sign(information, private)
        self.__certificat_ID = certificat.get_ID()
        self.__heure_date = datetime.datetime.now()

    def get_information(self):
        return self.__information

    def get_valeur_signature(self):
        return self.__valeur_signature

    def get_certificat_ID(self):
        return self.__certificat_ID

    def get_type(self):
        return "signature basique"