Utilisation de pycryptodome

Cryptage/Décryptage fonctionnel

.idea/workspace.xml

@@ -1,7 +1,11 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="ChangeListManager">
-    <list default="true" id="3be09a79-ba49-407e-8f34-349a7b2cd6dc" name="Changes" comment="" />
+    <list default="true" id="3be09a79-ba49-407e-8f34-349a7b2cd6dc" name="Changes" comment="">
+      <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/crypt.py" beforeDir="false" afterPath="$PROJECT_DIR$/crypt.py" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/main.py" beforeDir="false" afterPath="$PROJECT_DIR$/main.py" afterDir="false" />
+    </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
     <option name="HIGHLIGHT_NON_ACTIVE_CHANGELIST" value="false" />
@@ -19,6 +23,7 @@
     <property name="RunOnceActivity.OpenProjectViewOnStart" value="true" />
     <property name="RunOnceActivity.ShowReadmeOnStart" value="true" />
     <property name="last_opened_file_path" value="$PROJECT_DIR$" />
+    <property name="settings.editor.selected.configurable" value="com.jetbrains.python.configuration.PyActiveSdkModuleConfigurable" />
   </component>
   <component name="RunManager">
     <configuration name="main" type="PythonConfigurationType" factoryName="Python" nameIsGenerated="true">
@@ -28,7 +33,7 @@
       <envs>
         <env name="PYTHONUNBUFFERED" value="1" />
       </envs>
-      <option name="SDK_HOME" value="/usr/bin/python3.9" />
+      <option name="SDK_HOME" value="$PROJECT_DIR$/venv/bin/python" />
       <option name="WORKING_DIRECTORY" value="$PROJECT_DIR$" />
       <option name="IS_MODULE_SDK" value="false" />
       <option name="ADD_CONTENT_ROOTS" value="true" />

crypt.py

@@ -1,7 +1,7 @@
 import os, random, struct
 from Crypto.Cipher import AES
 
-def encrypt_file(key, in_filename, out_filename=None, chunksize=64*1024):
+def encrypt_file(key, in_file, out_file=None, chunksize=64 * 1024):
     """ Encrypts a file using AES (CBC mode) with the
         given key.
 
@@ -10,10 +10,10 @@ def encrypt_file(key, in_filename, out_filename=None, chunksize=64*1024):
             either 16, 24 or 32 bytes long. Longer keys
             are more secure.
 
-        in_filename:
+        in_file:
             Name of the input file
 
-        out_filename:
+        out_file:
             If None, '<in_filename>.enc' will be used.
 
         chunksize:
@@ -22,28 +22,27 @@ def encrypt_file(key, in_filename, out_filename=None, chunksize=64*1024):
             sizes can be faster for some files and machines.
             chunksize must be divisible by 16.
     """
-    if not out_filename:
+    if not out_file:
-        out_filename = in_filename + '.enc'
+        out_file = in_file + '.enc'
 
-    iv = ''.join(chr(random.randint(0, 0xFF)) for i in range(16))
+    cipher = AES.new(key, AES.MODE_CBC)
-    encryptor = AES.new(key, AES.MODE_CBC, iv)
+    filesize = os.path.getsize(in_file)
-    filesize = os.path.getsize(in_filename)
 
-    with open(in_filename, 'rb') as infile:
+    with open(in_file, 'rb') as infile:
-        with open(out_filename, 'wb') as outfile:
+        with open(out_file, 'wb') as outfile:
             outfile.write(struct.pack('<Q', filesize))
-            outfile.write(iv)
+            outfile.write(cipher.iv)
 
             while True:
                 chunk = infile.read(chunksize)
                 if len(chunk) == 0:
                     break
                 elif len(chunk) % 16 != 0:
-                    chunk += ' ' * (16 - len(chunk) % 16)
+                    chunk += b' ' * (16 - len(chunk) % 16)
 
-                outfile.write(encryptor.encrypt(chunk))
+                outfile.write(cipher.encrypt(chunk))
 
-def decrypt_file(key, in_filename, out_filename=None, chunksize=24*1024):
+def decrypt_file(key, in_file, out_file=None, chunksize=24 * 1024):
     """ Decrypts a file using AES (CBC mode) with the
         given key. Parameters are similar to encrypt_file,
         with one difference: out_filename, if not supplied
@@ -51,15 +50,17 @@ def decrypt_file(key, in_filename, out_filename=None, chunksize=24*1024):
         (i.e. if in_filename is 'aaa.zip.enc' then
         out_filename will be 'aaa.zip')
     """
-    if not out_filename:
+    #if not out_file:
-        out_filename = os.path.splitext(in_filename)[0]
+    #    out_file = os.path.splitext(in_file)[0]
+    if not out_file:
+        out_file = in_file + '.dec'
 
-    with open(in_filename, 'rb') as infile:
+    with open(in_file, 'rb') as infile:
         origsize = struct.unpack('<Q', infile.read(struct.calcsize('Q')))[0]
         iv = infile.read(16)
         decryptor = AES.new(key, AES.MODE_CBC, iv)
 
-        with open(out_filename, 'wb') as outfile:
+        with open(out_file, 'wb') as outfile:
             while True:
                 chunk = infile.read(chunksize)
                 if len(chunk) == 0:

main.py

@@ -1,3 +1,9 @@
 from crypt import *
+from Crypto.Random import get_random_bytes
 
-encrypt_file('0123456789abcdef', 'original_file.txt', 'crypted_file')
+key = get_random_bytes(32) # 32 bytes * 8 = 256 bits (1 byte = 8 bits)
+print(key)
+
+encrypt_file(key, 'original_file.txt')
+
+decrypt_file(key, 'original_file.txt.enc')