des.py

#DES加密算法的实现

#M -> Mlist -> IPM -> EIPM -> KEIPM -> SKEIPM -> PSKEIPM -> C
#            ^      ^       ^        ^         ^         ^
#            |      |       |        |         |         |
#         IP置换 扩展E变换 K加密  S盒变换   P盒变换   逆IP置换
#                           ^
#                           |
#                           PC置换



#!/usr/bin/env python3.4
# coding=utf-8

#8 * 8
IP = [58504234261810 2
      60524436282012 4
      62544638302214 6
      64564840322416 8
      574941332517 9 1
      59514335271911 3
      61534537292113 5
      63554739312315 7]
#8 * 8
IP_1=[40 8481656246432
      39 7471555236331
      38 6461454226230
      37 5451353216129
      36 4441252206028
      35 3431151195927
      34 2421050185826
      33 141 949175725]
#6 * 8
E = [32 1 2 3 4 5
      4 5 6 7 8 9
      8 910111213
     121314151617
     161718192021
     202122232425
     242526272829
     2829303132 1]
#1 * 8
SCASE = [“S1““S2““S3““S4““S5““S6““S7““S8“]
#8 * （4 * 16）
SD = {“S1“:[[1441312151183106125907]
            [0157414213110612119538]
            [4114813621115129731050]
            [1512824917511314100613]]
      “S2“:[[1518146113497213120510]
            [3134715281412011069115]
            [0147111041315812693215]
            [1381013154211671205149]]
      “S3“:[[1009146315511312711428]
            [1370934610285141211151]
            [1364981530111212510147]
            [1101306987415143115212]]
      “S4“:[[7131430691012851112415]
            [1381156150347212110149]
            [1069012117131513145284]
            [3150610113894511127214]]
      “S5“:[[2124171011685315130149]
            [1411212471315015103986]
            [4211110137815912563014]
            [1181271142136150910453]]
      “S6“:[[1211015926801334147511]
            [1015427129561131401138]
            [9141552812370410113116]
            [4321295151011141760813]]
      “S7“:[[4112141508133129751061]
            [1301174911014351221586]
            [1411131237141015680592]
            [6111381410795015142312]]
      “S8“:[[1328461511110931450127]
            [1151381037412561101492]
            [7114191214206101315358]
            [2114741081315129035611]]
            }
#8 * 4 = 32
P = [16 72021
     29122817