syndrill · December 8, 2019 21:55 · Nov 5, 2017 · Nov 5, 2017 · May 18, 2017
diff --git a/xxtea.py b/xxtea.py
@@ -1,3 +1,6 @@
+#!/usr/bin/env python
+# -*- coding: UTF-8 -*-
+
 import struct
 
 _DELTA = 0x9E3779B9
@@ -19,7 +22,7 @@ def _str2long(s, w):
     if w: v.append(n)
     return v
 
-def encrypt(str, key):
+def do_xxtea_encrypt(str, key):
     if str == '': return str
     v = _str2long(str, True)
     k = _str2long(key.ljust(16, "\0"), False)
@@ -41,7 +44,7 @@ def encrypt(str, key):
         q -= 1
     return _long2str(v, False)
 
-def decrypt(str, key):
+def do_xxtea_decrypt(str, key):
     if str == b'': return str
     v = _str2long(str, False)
     k = _str2long(key.ljust(16, b"\0"), False)
@@ -60,4 +63,20 @@ def decrypt(str, key):
         v[0] = (v[0] - ((z >> 5 ^ y << 2) + (y >> 3 ^ z << 4) ^ (sum ^ y) + (k[0 & 3 ^ e] ^ z))) & 0xffffffff
         y = v[0]
         sum = (sum - _DELTA) & 0xffffffff
-    return _long2str(v, True)
+    return _long2str(v, True)
+
+def fix_key_length(key):
+    key = key + ('\x00'  * (16 - len(key))) 
+    return key
+
+def decrypt(str, key):
+    if len(key) < 16:
+    	res = do_xxtea_decrypt(str, fix_key_length(key))
+    else:
+    	res = do_xxtea_decrypt(str, key)
+
+def encrypt(str, key):
+    if len(key) < 16:
+    	res = do_xxtea_encrypt(str, fix_key_length(key))
+    else:
+    	res = do_xxtea_encrypt(str, key)
diff --git a/xxtea.py b/xxtea.py
@@ -0,0 +1,63 @@
+import struct
+
+_DELTA = 0x9E3779B9
+
+def _long2str(v, w):
+    n = (len(v) - 1) << 2
+    if w:
+        m = v[-1]
+        if (m < n - 3) or (m > n): return ''
+        n = m
+    s = struct.pack('<%iL' % len(v), *v)
+    return s[0:n] if w else s
+
+def _str2long(s, w):
+    n = len(s)
+    m = (4 - (n & 3) & 3) + n
+    s = s.ljust(m, b"\0")
+    v = list(struct.unpack('<%iL' % (m >> 2), s))
+    if w: v.append(n)
+    return v
+
+def encrypt(str, key):
+    if str == '': return str
+    v = _str2long(str, True)
+    k = _str2long(key.ljust(16, "\0"), False)
+    n = len(v) - 1
+    z = v[n]
+    y = v[0]
+    sum = 0
+    q = 6 + 52 // (n + 1)
+    while q > 0:
+        sum = (sum + _DELTA) & 0xffffffff
+        e = sum >> 2 & 3
+        for p in xrange(n):
+            y = v[p + 1]
+            v[p] = (v[p] + ((z >> 5 ^ y << 2) + (y >> 3 ^ z << 4) ^ (sum ^ y) + (k[p & 3 ^ e] ^ z))) & 0xffffffff
+            z = v[p]
+        y = v[0]
+        v[n] = (v[n] + ((z >> 5 ^ y << 2) + (y >> 3 ^ z << 4) ^ (sum ^ y) + (k[n & 3 ^ e] ^ z))) & 0xffffffff
+        z = v[n]
+        q -= 1
+    return _long2str(v, False)
+
+def decrypt(str, key):
+    if str == b'': return str
+    v = _str2long(str, False)
+    k = _str2long(key.ljust(16, b"\0"), False)
+    n = len(v) - 1
+    z = v[n]
+    y = v[0]
+    q = 6 + 52 // (n + 1)
+    sum = (q * _DELTA) & 0xffffffff
+    while (sum != 0):
+        e = sum >> 2 & 3
+        for p in range(n, 0, -1):
+            z = v[p - 1]
+            v[p] = (v[p] - ((z >> 5 ^ y << 2) + (y >> 3 ^ z << 4) ^ (sum ^ y) + (k[p & 3 ^ e] ^ z))) & 0xffffffff
+            y = v[p]
+        z = v[n]
+        v[0] = (v[0] - ((z >> 5 ^ y << 2) + (y >> 3 ^ z << 4) ^ (sum ^ y) + (k[0 & 3 ^ e] ^ z))) & 0xffffffff
+        y = v[0]
+        sum = (sum - _DELTA) & 0xffffffff
+    return _long2str(v, True)