Description of De-crypter

Description of the Main Raptor’s Cryptographic Algorithm

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Algorithm

This is the main solver algorithm program. It allow us to decrypt datas slices crypted with the version 1 of the Raptor Cryptographic Algorithm. To solve I need thse following variables :

• chaine : The input crypted string storage

• Basemin : The minimum Base index

• Basemax : The maximum Base index

• table2 : The list of list containing the Base Table

• finalkey : The key of the algorithm, the decrypting process absolutely need this key.

The solving procedure is ruled by the following steps:

• Generating the Base Table and store it into my table2 variable

• Getting inputs known as crypted string and his associated key.

• Decrypting process using the decrypt_procedure method (see documentation)

• Store and return the results of decrypting process

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Source Code

import sys
import math as m

represent=''
table2 = []
dic = {}
main_dic={}
choice = ' '
chaine=''
print("----------------------------------------------------------------------------------")

if(len(sys.argv)!=4):
        Basemin = 2
        Basemax = 37
        Range   = 36**2
else :
        Basemin = int(sys.argv[1])
        Basemax = int(sys.argv[2])
        Range   = int(sys.argv[3])

if(Basemin<2 or Basemax>37):
        print("Affichage impossible veuillez selectionner une plage de valeure contenue dans [2,36]")
        exit(0)

maxi=Basemax-Basemin

for i in range(Basemin,Basemax):
        table2.append(table(i,0,Range,1))

for i in range (0,len(table2)):
        table2[i]=splitTable(table2[i])

for j in range (0,len(table2)):
        table2[j]=rec_table_construct_lvl1(table2[j],j+2,1,0)
        for k in range(0,j+2):
                table2[j][k]=(str(0)+table2[j][k])
table2  = rec_manage(table2)

finalke=[]
while(choice!='q'):
        finalke[:]=[]
        finalkey=''
        decrypt=''
        chaine=input("Veuillez entrer la chaine cryptée : \n")
        print("----------------------------------------------------------------------------------")
        finalkey= input("Veuillez saisir la clé : \n")
        finalke = miam(finalkey)
        decrypt = decrypt_procedure(chaine,finalke,table2)
        print("----------------------------------------------------------------------------------")
        print("Chaine decryptée : ")
        print(decrypt)
        choice=input("c)ontinuer ou q)uitter ?")