feat(wpcarro/scratch): Upload my solutions to cryptopals

More beginner problems/solutions for CTF-style challenges.

Change-Id: Ide229e99e3ccc1ede5a5ca1c2ad039498e49ea4c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/4740
Reviewed-by: wpcarro <wpcarro@gmail.com>
Autosubmit: wpcarro <wpcarro@gmail.com>
Tested-by: BuildkiteCI

users/wpcarro/scratch/cryptopals/set1/c2.py

@@ -0,0 +1,20 @@
+def fixed_xor(x, y, decode_hex=True, encode_hex=True):
+    if decode_hex:
+        x = bytearray.fromhex(x)
+        y = bytearray.fromhex(y)
+
+    result = bytearray(len(x))
+
+    for i in range(len(x)):
+        result[i] = x[i] ^ y[i]
+
+    return result.hex() if encode_hex else result
+
+run_tests = False
+if run_tests:
+    actual = fixed_xor("1c0111001f010100061a024b53535009181c", "686974207468652062756c6c277320657965")
+    expect = "746865206b696420646f6e277420706c6179"
+
+    print(actual)
+    assert actual == expect
+    print("Success!")