upload symcryptool

Author: APS-CS

symcryptool/cryptool.py

@@ -0,0 +1,136 @@
+import os
+import argparse
+from cryptography.fernet import Fernet
+
+parser = argparse.ArgumentParser(description=r"""
+
+_________                                   __                .__   
+\_   ___ \_______ ___.__.______           _/  |_  ____   ____ |  |  
+/    \  \/\_  __ <   |  |\____ \   ______ \   __\/  _ \ /  _ \|  |  
+\     \____|  | \/\___  ||  |_> > /_____/  |  | (  <_> |  <_> )  |__
+ \______  /|__|   / ____||   __/           |__|  \____/ \____/|____/
+        \/        \/     |__|                                       
+
+
+Usage:
+                    py SCRIPT.py -f FILE -k KEY -e/d
+
+Flags:
+-c  --create_key    Create a new encryption key and save it as a new file.
+
+-f  --files         Specify the file you want to encrypt or decrypt.
+                    Note: Does not encrypt .enc files and only decrypts .enc files.
+
+-e  --encrypt       Use -e to encrypt the specified file with the selected key file.
+                    Note: An encrypted copy with the extension The fileAME.EXTENSION.enc will be created in the current directory.
+
+-d  --decrypt       Use -d to decrypt the specified file with the selected key file.
+                    Note: A decrypted copy with the The fileame decrypted_The fileAME.EXTENSION will be created in the current directory.
+
+-k  --key           Specify the key file you want to use for encryption or decryption.
+
+                                 
+Examples of correct usage:
+Create a new key:    py cryptool.py -c new_key.key
+
+Encrypt a file:      py cryptool.py -f testfile.txt -k test.key -e
+
+Decrypt a file:      py cryptool.py -f testfile.txt.enc -k test.key -d""", 
+epilog="See information above", formatter_class=argparse.RawDescriptionHelpFormatter)   
+
+def generate_key_mode(name_key_in_gkm):
+    newkey = Fernet.generate_key()
+    with open(name_key_in_gkm, "wb") as key_file:
+        key_file.write(newkey)
+
+def encrypt_and_store_info(file, key):
+    with open(key, "rb") as key_file:
+        key = key_file.read()
+
+    cipher_suite = Fernet(key)
+
+    with open(file, "rb") as file_to_encrypt:                      
+        content = file_to_encrypt.read()
+        cipher_content = cipher_suite.encrypt(content)
+        
+        encrypted_file = file + ".enc"
+        with open(encrypted_file, "wb") as file_to_encrypt:
+            file_to_encrypt.write(cipher_content)
+
+def decrypt_and_store_info(file, key):
+    with open(key, "rb") as key_file:
+        key = key_file.read()
+
+    cipher_suite = Fernet(key)
+
+    with open(file, "rb") as file_to_decrypt:                      
+        content = file_to_decrypt.read()
+        cipher_content = cipher_suite.decrypt(content)
+        
+        decrypted_file = "decrypted_" + file.replace(".enc", "")
+        with open(decrypted_file, "wb") as file_to_decrypt:
+            file_to_decrypt.write(cipher_content)
+
+def main():
+
+    parser.add_argument("-c", "--create_key", metavar="Create new key", help="Create a new encryption key")
+    parser.add_argument("-f", "--file", metavar="Choose: File", type=str, help="Choose file to encrypt or decrypt") 
+    parser.add_argument("-k", "--key", metavar="Choose: Key", type=str, help="Choose key-file to encrypt or decrypt file") 
+
+    group = parser.add_mutually_exclusive_group()
+    group.add_argument("-e", "--encrypt", action="store_true", help="Choose for encryption")
+    group.add_argument("-d", "--decrypt", action="store_true", help="Choose for decryption")
+
+    args = parser.parse_args()
+
+    if len(os.sys.argv) == 1:
+        parser.print_help()
+        return
+
+    if args.create_key:
+        if not os.path.exists(args.create_key):
+            generate_key_mode(args.create_key)
+            print(f"Key {args.create_key} created.")
+        else:
+            print(f"Key {args.create_key} already exists.")
+
+    if (args.file and args.key) and not (args.encrypt or args.decrypt):
+        print("Error: You need to specify the encryption mode '-e' or '-d'.")
+        return
+
+    if args.file and (args.decrypt or args.encrypt):
+        if not os.path.exists(args.file):
+            print(f"File {args.file} does not exist.")
+            return
+        excisting_file = args.file
+    else:
+        print("Error: Choose a file. Choose '-f' and file.")
+        return
+
+    if args.key and (args.decrypt or args.encrypt):
+        if not os.path.exists(args.key):
+            print(f"Keyfile {args.key}finns ej.")
+            return
+        excisting_key = args.key
+    else:
+        print("Error: Key file missing. Choose '-k' and key-file.")
+        return
+             
+
+    if args.encrypt:
+        if excisting_file.endswith(".enc"):
+            print(f"The file {excisting_file} is already encrypted.")
+        else:
+            encrypt_and_store_info(excisting_file, excisting_key)
+            print(f"The file {excisting_file} is encrypted.")
+        
+    if  args.decrypt:
+        if not excisting_file.endswith(".enc"):
+            print(f"The file {excisting_file} is already decrypted.")
+        else:
+            decrypt_and_store_info(excisting_file, excisting_key)
+            print(f"The file {excisting_file} is decrypted.")
+
+
+if __name__ == "__main__":
+    main()