From 303437435f4b6ec660a8b289055fa190e1028328 Mon Sep 17 00:00:00 2001
From: Holden Rohrer <holden.rohrer@gmail.com>
Date: Mon, 11 Nov 2019 22:53:52 -0500
Subject: simpler rsa

---
 final/rsa-decrypt.py | 29 +++++++++++++++++++++++++++++
 final/rsa-encrypt.py | 22 ++++++++++++++++++++++
 2 files changed, 51 insertions(+)
 create mode 100644 final/rsa-decrypt.py
 create mode 100644 final/rsa-encrypt.py

(limited to 'final')

diff --git a/final/rsa-decrypt.py b/final/rsa-decrypt.py
new file mode 100644
index 0000000..335ed68
--- /dev/null
+++ b/final/rsa-decrypt.py
@@ -0,0 +1,29 @@
+encrypted = [405, 35, 133, 371, 435, 279] # Directly from demo output of encrypted
+p = 29
+q = 17
+n = p*q
+tot = (p-1)*(q-1)
+e = 3
+
+# Calculate d such that ed == 1 mod tot
+d = 1 # Guess
+while (e*d % tot != 1):
+  d += 1
+# Algorithm is currently extremely dumb
+
+def decrypt_block(blk):
+  return blk**d % n
+
+decrypted = [decrypt_block(block) for block in encrypted]
+
+messagenum = 0
+for block in decrypted:
+  messagenum += block
+  messagenum *= n
+
+message = ''
+while messagenum > 0:
+  message += chr(messagenum%128)
+  messagenum = (messagenum-messagenum%128)//128
+
+print(message)
diff --git a/final/rsa-encrypt.py b/final/rsa-encrypt.py
new file mode 100644
index 0000000..05cf562
--- /dev/null
+++ b/final/rsa-encrypt.py
@@ -0,0 +1,22 @@
+p = 29
+q = 17
+n = p*q
+tot = (p-1)*(q-1)
+e = 3 # Many present strictly for convenience's sake
+
+message = 'abcdef'
+messagenum = 0
+for char in message:
+  messagenum += ord(char)
+  messagenum *= 128 # Assuming ASCII only characters
+
+messageblocks = []
+while messagenum > 0:
+  messageblocks.append(messagenum%n)
+  messagenum = (messagenum-messagenum%n)//n
+
+def encrypt_block(blk):
+  return (blk ** e) % n
+
+encrypted = [encrypt_block(block) for block in messageblocks]
+print(encrypted)
-- 
cgit