refactor aes.py, aes-buffer to use pycrypto

--HG--
branch : pmacs2

aes.py

@@ -1,112 +1,29 @@
-#!/usr/bin/python
+import Crypto.Hash.SHA256
-#
+import Crypto.Cipher.AES
-# by Erik Osheim
-import os
-from subprocess import Popen, PIPE
 
-class Cipher(object):
+class Crypter(object):
-    '''Cipher represents a particular hashing strategy (password, seed, and type). Cipher can encrypt or decrypt data.'''
+    ALIGNMENT = 16
-    def __init__(self, password, seed='aes.py', hashtype='rmd160'):
+    def __init__(self, password, salt='aes.py'):
         self.password = password
-        self.seed     = seed
+        self.salt     = salt
-        self.hashtype = hashtype
+        self.hash     = Crypto.Hash.SHA256.new(password + salt)
+        self.cipher   = Crypto.Cipher.AES.new(self.hash.digest())
+
+    def pad(self, s):
+        xtra = len(s) % self.ALIGNMENT
+        if xtra:
+            return s + '\x00' * (self.ALIGNMENT - xtra)
+        else:
+            return s
+    
+    def unpad(self, s):
+        l = len(s)
+        while l > 0 and s[l - 1] == '\x00':
+            l -= 1
+        return s[:l]
+    
     def encrypt(self, data):
-        return encrypt_data(data, self.password, self.seed, self.hashtype)
+        return self.cipher.encrypt(self.pad(data))
-    def decrypt(self, encrypted):
-        return decrypt_data(encrypted, self.password, self.seed, self.hashtype)
     
-def _check_aespipe():
+    def decrypt(self, data):
-    '''This function checks if we have the "aespipe" binary in $PATH'''
+        return self.unpad(self.cipher.decrypt(self.pad(data)))
-    result = os.system('which aespipe > /dev/null')
-    if result != 0:
-        raise Exception, "Could not find aespipe; is it installed?"
-
-def encrypt_data(data, password, seed='aes.py', hashtype='rmd160'):
-    '''Uses password to encrypt data'''
-    _check_aespipe()
-    args = ["aespipe", "-S", seed, "-H", hashtype, "-p", "0"]
-    p = Popen(args, stdin=PIPE, stdout=PIPE, stderr=PIPE)
-    (stdout, stdin, stderr) = (p.stdout, p.stdin, p.stderr)
-    stdin.write(password + '\n')
-    stdin.write(data)
-    stdin.close()
-    encrypted = stdout.read()
-    err = stderr.read()
-    if err:
-        raise Exception, "Problem: %s" % err
-    return encrypted
-
-def encrypt_path(path, data, password, seed='aes.py', hashtype='rmd160'):
-    '''Uses password to encrypt data and writes result to path'''
-    encrypted = encrypt_data(data, password, seed, hashtype)
-    f = open(path, 'w')
-    f.write(encrypted)
-    f.close()
-
-def decrypt_data(encrypted, password, seed='aes.py', hashtype='rmd160'):
-    '''Uses password to decrypt data'''
-    _check_aespipe()
-    args = ["aespipe", "-d", "-S", seed, "-H", hashtype, "-p", "0"]
-    p = Popen(args, stdin=PIPE, stdout=PIPE, stderr=PIPE)
-    (stdout, stdin, stderr) = (p.stdout, p.stdin, p.stderr)
-    stdin.write(password + '\n')
-    stdin.write(encrypted)
-    stdin.close()
-    data = stdout.read()
-    err = stderr.read()
-    if err:
-        raise Exception, "Problem: %s" % err
-
-    # data is null-padded at the end to align on 16 or 512 bytes boundaries
-    i = len(data)
-    while i > 1:
-        if data[i-1] == '\x00':
-            i -= 1
-        else:
-            break
-    return data[:i]
-
-def decrypt_path(path, password, seed='aes.py', hashtype='rmd160'):
-    '''Uses password to decrypt data from path'''
-    f = open(path, 'r')
-    encrypted = f.read()
-    f.close()
-    data = decrypt_data(encrypted, password, seed, hashtype)
-    return data
-
-if __name__ == "__main__":
-    import optparse, sys
-
-    parser = optparse.OptionParser()
-    parser.set_defaults(mode='decrypt')
-    parser.set_defaults(password='insecure1@3$5^')
-    parser.set_defaults(filename='output.aes')
-
-    parser.add_option('-e', dest='mode', action='store_const', const='encrypt',
-                      help="perform encryption on data from stdin")
-    parser.add_option('-d', dest='mode', action='store_const', const='decrypt',
-                      help="perform decryption on data from stdin")
-    parser.add_option('-f', dest='filename', action='store', metavar='FILENAME',
-                      help="encrypt to/from FILENAME (default: output.aes)")
-    parser.add_option('-p', dest='password', action='store', metavar='PASSWORD',
-                      default="insecure1@3$5^",
-                      help="use password PASSWORD (default: insecure1@3$5^)")
-
-    (opts, args) = parser.parse_args()
-
-    c = Cipher(opts.password)
-
-    if opts.mode == 'encrypt':
-        data = sys.stdin.read()
-        encrypted = c.encrypt(data)
-        f = open(opts.filename, 'w')
-        f.write(encrypted)
-        f.close()
-        print "data written to %r." % opts.filename
-    else:
-        print "reading data from %r:" % opts.filename
-        f = open(opts.filename, 'r')
-        encrypted = f.read()
-        f.close()
-        data = c.decrypt(encrypted)
-        print data

application.py

@@ -5,7 +5,7 @@ import traceback
 from subprocess import Popen, PIPE, STDOUT
 
 import buffer, buffer.about, buffer.color, buffer.console, buffer.data
-import buffer.fs
+import buffer.fs, buffer.aes
 import bufferlist, color, completer, ispell, keyinput, method, minibuffer
 import mode, util, window
 from point import Point
@@ -369,7 +369,7 @@ class Application(object):
                 if not password:
                     raise Exception, "password is required"
                 if not os.path.exists(path) or os.path.isfile(path):
-                    b = buffer.AesBuffer(path, password, name=name)
+                    b = buffer.aes.AesBuffer(path, password, name=name)
                 else:
                     raise Exception, "not a file or dir: %r" % path
             try:
@@ -1014,7 +1014,7 @@ class Application(object):
 def open_aes_file(path, name=None, binary=False):
     if os.path.isfile(path) or not os.path.exists(path):
         p = getpass.getpass("Please enter the AES password: ")
-        return buffer.AesBuffer(path, p, name)
+        return buffer.aes.AesBuffer(path, p, name)
     else:
         raise Exception, "can't open %r; unsupported file type" % path
 def open_plain_file(path, name=None, binary=False):

buffer/__init__.py

@@ -1,7 +1,8 @@
 from util import defaultdict
 import codecs, datetime, grp, os, pwd, re, shutil, stat, string
 import fcntl, select, pty, threading
-import aes, dirutil, regex, highlight, lex, term
+#import aes, dirutil, regex, highlight, lex, term
+import dirutil, regex, highlight, lex, term
 from point import Point
 from subprocess import Popen, PIPE, STDOUT
 from keyinput import MAP
@@ -665,6 +666,7 @@ class FileBuffer(Buffer):
             temp_path = self._temp_path()
             shutil.copyfile(self.path, temp_path)
 
+
         try:
             data = self.make_string()
             if self.windows[0].mode.savetabs:
@@ -674,8 +676,9 @@ class FileBuffer(Buffer):
             f2 = self._open_file_w(self.path, preserve=False)
             f2.write(self.bytemark + data)
             f2.close()
-        except:
+        except Exception, e:
             if exists: shutil.copyfile(temp_path, self.path)
+            raise e
         else:
             self.store_checksum(data)
             self.modified = False
@@ -684,16 +687,16 @@ class FileBuffer(Buffer):
         self.path = path
         self.save()
 
-class AesBuffer(FileBuffer):
+#class AesBuffer(FileBuffer):
-    btype = 'aesfile'
+#    btype = 'aesfile'
-    def __init__(self, path, password, name=None):
+#    def __init__(self, path, password, name=None):
-        '''fb = FileBuffer(path)'''
+#        '''fb = FileBuffer(path)'''
-        FileBuffer.__init__(self, path, name)
+#        FileBuffer.__init__(self, path, name)
-        self.password = password
+#        self.password = password
-    def read_filter(self, data):
+#    def read_filter(self, data):
-        return aes.decrypt_data(data, self.password)
+#        return aes.decrypt_data(data, self.password)
-    def write_filter(self, data):
+#    def write_filter(self, data):
-        return aes.encrypt_data(data, self.password)
+#        return aes.encrypt_data(data, self.password)
 
 class Binary32Buffer(FileBuffer):
     btype     = 'bin32file'

buffer/aes.py

@@ -0,0 +1,13 @@
+import aes
+from buffer import FileBuffer
+
+class AesBuffer(FileBuffer):
+    btype = 'aesfile'
+    def __init__(self, path, password, name=None):
+        '''ab = AesBuffer(path, password)'''
+        FileBuffer.__init__(self, path, name)
+        self.crypter = aes2.Crypter(password)
+    def read_filter(self, data):
+        return self.crypter.decrypt(data)
+    def write_filter(self, data):
+        return self.crypter.encrypt(data)