Merge pull request #86 from Sankalp75/add-encrypt-decrypt-tool

Author: AseanK

README.md

@@ -141,6 +141,7 @@ python "file_name.py"
 - [Binary Converter](Tools/binary_converter)
 - [Expense Tracker](<Tools/Expense Tracker>)
 - [Encoding and decoding images](<Tools/Image encoding and decoding>)
+- [Encrypt and Decrypt Tool](Tools/encrypt_decrypt_tool)
 
 <!--TOOLS_END-->
 

Tools/encrypt_decrypt_tool/README.md

@@ -0,0 +1,24 @@
+<p align="center">
+  <a href="https://github.com/AseanK/python-tools-and-games" target="_blank">
+    <img src="../../images/tools_logo.png" width = "2560px" height = "200px">
+  </a>
+</p>
+
+# Encrypt and Decrypt Tool
+<!-- Tools features -->
+## Features
+1. Encrypt long text directly from the command line.
+2. Decrypt encrypted strings back to plain text.
+3. Encrypt entire files, like documents or images.
+4. Generates a secure, cryptographically strong key for safe AES-128 encryption (via Fernet).
+
+## How to install and run
+1. Fork the repo by clicking the fork logo on the top right <img src="../../images/fork.png" width="300" height="60">
+2. Clone the repo `git clone git@github.com:AseanK/python-tools-and-games.git`
+3. Head to the `Tools/encrypt_decrypt_tool` folder
+4. Install the requirements using `pip install -r requirements.txt`
+5. Generate a new key by running: `python encrypt_decrypt.py keygen`
+6. Encrypt text: `python encrypt_decrypt.py encrypt --key YOUR_KEY --text "my secret"`
+7. Decrypt text: `python encrypt_decrypt.py decrypt --key YOUR_KEY --text "encrypted_string"`
+8. Encrypt a file: `python encrypt_decrypt.py encrypt --key YOUR_KEY --file document.pdf`
+9. Run `python encrypt_decrypt.py -h` to see all available commands.

Tools/encrypt_decrypt_tool/encrypt_decrypt.py

@@ -0,0 +1,121 @@
+import argparse
+import sys
+import os
+
+try:
+    from cryptography.fernet import Fernet
+except ImportError:
+    print("Please install the 'cryptography' library. Run: pip install -r requirements.txt")
+    sys.exit(1)
+
+def generate_key():
+    key = Fernet.generate_key()
+    print(f"Generated Key: {key.decode('utf-8')}")
+    print("Please save this key in a secure location. You will need it to decrypt your data.")
+
+def encrypt_data(data, key):
+    f = Fernet(key)
+    return f.encrypt(data)
+
+def decrypt_data(data, key):
+    f = Fernet(key)
+    return f.decrypt(data)
+
+def main():
+    parser = argparse.ArgumentParser(description="Encrypt and decrypt files or text using symmetric encryption.")
+    subparsers = parser.add_subparsers(dest="command", help="Available commands")
+
+    # Command: keygen
+    parser_keygen = subparsers.add_parser("keygen", help="Generate a new encryption key")
+
+    # Command: encrypt
+    parser_encrypt = subparsers.add_parser("encrypt", help="Encrypt a file or text")
+    parser_encrypt.add_argument("-k", "--key", required=True, help="Encryption key (base64 encoded)")
+    group_enc = parser_encrypt.add_mutually_exclusive_group(required=True)
+    group_enc.add_argument("-t", "--text", help="Text to encrypt")
+    group_enc.add_argument("-f", "--file", help="File to encrypt")
+    parser_encrypt.add_argument("-o", "--out", help="Output file to save the encrypted data (optional)")
+
+    # Command: decrypt
+    parser_decrypt = subparsers.add_parser("decrypt", help="Decrypt a file or text")
+    parser_decrypt.add_argument("-k", "--key", required=True, help="Decryption key (base64 encoded)")
+    group_dec = parser_decrypt.add_mutually_exclusive_group(required=True)
+    group_dec.add_argument("-t", "--text", help="Text to decrypt")
+    group_dec.add_argument("-f", "--file", help="File to decrypt")
+    parser_decrypt.add_argument("-o", "--out", help="Output file to save the decrypted data (optional)")
+
+    args = parser.parse_args()
+
+    if args.command == "keygen":
+        generate_key()
+    
+    elif args.command == "encrypt":
+        try:
+            key = args.key.encode('utf-8')
+            if args.text:
+                encrypted = encrypt_data(args.text.encode('utf-8'), key)
+                if args.out:
+                    with open(args.out, 'wb') as f:
+                        f.write(encrypted)
+                    print(f"Encrypted text saved to: {args.out}")
+                else:
+                    print(f"Encrypted text: {encrypted.decode('utf-8')}")
+            
+            elif args.file:
+                if not os.path.isfile(args.file):
+                    print(f"Error: File '{args.file}' not found.")
+                    sys.exit(1)
+                with open(args.file, 'rb') as f:
+                    data = f.read()
+                encrypted = encrypt_data(data, key)
+                
+                out_file = args.out if args.out else args.file + ".enc"
+                with open(out_file, 'wb') as f:
+                    f.write(encrypted)
+                print(f"Encrypted file saved to: {out_file}")
+                
+        except Exception as e:
+            print(f"Encryption failed: {e}")
+
+    elif args.command == "decrypt":
+        try:
+            key = args.key.encode('utf-8')
+            if args.text:
+                decrypted = decrypt_data(args.text.encode('utf-8'), key)
+                if args.out:
+                    with open(args.out, 'wb') as f:
+                        f.write(decrypted)
+                    print(f"Decrypted text saved to: {args.out}")
+                else:
+                    try:
+                        print(f"Decrypted text: {decrypted.decode('utf-8')}")
+                    except UnicodeDecodeError:
+                        print(f"Decrypted data is not valid UTF-8. Please save to a file using -o/--out.")
+            
+            elif args.file:
+                if not os.path.isfile(args.file):
+                    print(f"Error: File '{args.file}' not found.")
+                    sys.exit(1)
+                with open(args.file, 'rb') as f:
+                    data = f.read()
+                decrypted = decrypt_data(data, key)
+                
+                out_file = args.out
+                if not out_file:
+                    if args.file.endswith(".enc"):
+                        out_file = args.file[:-4]
+                    else:
+                        out_file = args.file + ".dec"
+                        
+                with open(out_file, 'wb') as f:
+                    f.write(decrypted)
+                print(f"Decrypted file saved to: {out_file}")
+                
+        except Exception as e:
+            print(f"Decryption failed: {e}")
+            print("Make sure you are using the correct key and valid encrypted data.")
+    else:
+        parser.print_help()
+
+if __name__ == "__main__":
+    main()

Tools/encrypt_decrypt_tool/requirements.txt

@@ -0,0 +1 @@
+cryptography==42.0.5