From f12a4f3856c8dbca5996f8f0eecfa2063c8f04eb Mon Sep 17 00:00:00 2001 From: Apprentice Harper Date: Mon, 23 Nov 2020 14:22:48 +0000 Subject: [PATCH] Revert to byte arrays for maps on PC, and so fix for Mac which still used byte arrays. Remove some unused code. --- DeDRM_plugin/kindlekey.py | 53 +++++++++++++-------------------------- 1 file changed, 18 insertions(+), 35 deletions(-) diff --git a/DeDRM_plugin/kindlekey.py b/DeDRM_plugin/kindlekey.py index aabb275..3816e1e 100644 --- a/DeDRM_plugin/kindlekey.py +++ b/DeDRM_plugin/kindlekey.py @@ -157,27 +157,25 @@ def primes(n): # Encode the bytes in data with the characters in map # data and map should be byte arrays def encode(data, map): - result = '' + result = b'' for char in data: value = char Q = (value ^ 0x80) // len(map) R = value % len(map) - result += map[Q] - result += map[R] - return result.encode('utf-8') + result += bytes([map[Q]]) + result += bytes([map[R]]) + return result # Hash the bytes in data and then encode the digest with the characters in map def encodeHash(data,map): - h = MD5(data) - return encode(h,map) + return encode(MD5(data),map) # Decode the string in data with the characters in map. Returns the decoded bytes def decode(data,map): - str_data = data.decode() result = b'' - for i in range (0,len(str_data)-1,2): - high = map.find(str_data[i]) - low = map.find(str_data[i+1]) + for i in range (0,len(data)-1,2): + high = map.find(data[i]) + low = map.find(data[i+1]) if (high == -1) or (low == -1) : break value = (((high * len(map)) ^ 0x80) & 0xFF) + low @@ -234,16 +232,8 @@ if iswindows: class DecryptNotBlockAlignedError(DecryptError): """ Error in decryption processing """ - def xorS(a,b): - """ XOR two strings """ - assert len(a)==len(b) - x = [] - for i in range(len(a)): - x.append( chr(ord(a[i])^ord(b[i]))) - return ''.join(x) - def xor(a,b): - """ XOR two strings """ + """ XOR two byte arrays, to lesser length """ x = [] for i in range(min(len(a),len(b))): x.append( a[i] ^ b[i]) @@ -442,11 +432,10 @@ if iswindows: 7: {4:13, 5:13, 6:13, 7:13, 8:14}, 8: {4:14, 5:14, 6:14, 7:14, 8:14}} #------------------------------------- - def keyExpansion(algInstance, keyString): - """ Expand a string of size keySize into a larger array """ + def keyExpansion(algInstance, keyArray): + """ Expand a byte array of size keySize into a larger array """ Nk, Nb, Nr = algInstance.Nk, algInstance.Nb, algInstance.Nr # for readability - key = [byte for byte in keyString] # convert string to list - w = [[key[4*i],key[4*i+1],key[4*i+2],key[4*i+3]] for i in range(Nk)] + w = [[keyArray[4*i],keyArray[4*i+1],keyArray[4*i+2],keyArray[4*i+3]] for i in range(Nk)] for i in range(Nk,Nb*(Nr+1)): temp = w[i-1] # a four byte column if (i%Nk) == 0 : @@ -792,14 +781,9 @@ if iswindows: # [c_char_p, c_ulong, c_char_p, c_ulong, c_ulong, c_ulong, c_char_p]) def pbkdf2(self, passwd, salt, iter, keylen): - def xorstr( a, b ): - if len(a) != len(b): - raise Exception("xorstr(): lengths differ") - return ''.join((chr(ord(x)^ord(y)) for x, y in zip(a, b))) - def xorbytes( a, b ): if len(a) != len(b): - raise Exception("xorstr(): lengths differ") + raise Exception("xorbytes(): lengths differ") return bytes([x ^ y for x, y in zip(a, b)]) def prf( h, data ): @@ -842,12 +826,12 @@ if iswindows: # Various character maps used to decrypt kindle info values. # Probably supposed to act as obfuscation - charMap2 = "AaZzB0bYyCc1XxDdW2wEeVv3FfUuG4g-TtHh5SsIiR6rJjQq7KkPpL8lOoMm9Nn_" - charMap5 = "AzB0bYyCeVvaZ3FfUuG4g-TtHh5SsIiR6rJjQq7KkPpL8lOoMm9Nn_c1XxDdW2wE" + charMap2 = b"AaZzB0bYyCc1XxDdW2wEeVv3FfUuG4g-TtHh5SsIiR6rJjQq7KkPpL8lOoMm9Nn_" + charMap5 = b"AzB0bYyCeVvaZ3FfUuG4g-TtHh5SsIiR6rJjQq7KkPpL8lOoMm9Nn_c1XxDdW2wE" # New maps in K4PC 1.9.0 - testMap1 = "n5Pr6St7Uv8Wx9YzAb0Cd1Ef2Gh3Jk4M" - testMap6 = "9YzAb0Cd1Ef2n5Pr6St7Uvh3Jk4M8WxG" - testMap8 = "YvaZ3FfUm9Nn_c1XuG4yCAzB0beVg-TtHh5SsIiR6rJjQdW2wEq7KkPpL8lOoMxD" + testMap1 = b"n5Pr6St7Uv8Wx9YzAb0Cd1Ef2Gh3Jk4M" + testMap6 = b"9YzAb0Cd1Ef2n5Pr6St7Uvh3Jk4M8WxG" + testMap8 = b"YvaZ3FfUm9Nn_c1XuG4yCAzB0beVg-TtHh5SsIiR6rJjQdW2wEq7KkPpL8lOoMxD" # interface with Windows OS Routines class DataBlob(Structure): @@ -987,7 +971,6 @@ if iswindows: print ('Could not find the folder in which to look for kinfoFiles.') else: # Probably not the best. To Fix (shouldn't ignore in encoding) or use utf-8 - # print("searching for kinfoFiles in " + path.encode('ascii', 'ignore')) print("searching for kinfoFiles in " + path) # look for (K4PC 1.25.1 and later) .kinf2018 file