From 6730bf4d0ffe511b03c4d58f79fdd0999ad4fdbe Mon Sep 17 00:00:00 2001
From: "E. Almqvist" <elalmqvist@gmail.com>
Date: Thu, 24 Feb 2022 21:28:48 +0100
Subject: [PATCH] Stuff

---
 ma5/rsa/brute.rb |  0
 ma5/rsa/rsa.rb   | 65 +++++++++++++++++++++++++++++++++---------------
 ma5/rsa/test.rb  | 27 ++++++++++++++++++++
 3 files changed, 72 insertions(+), 20 deletions(-)
 mode change 100755 => 100644 ma5/rsa/brute.rb
 create mode 100755 ma5/rsa/test.rb

diff --git a/ma5/rsa/brute.rb b/ma5/rsa/brute.rb
old mode 100755
new mode 100644
diff --git a/ma5/rsa/rsa.rb b/ma5/rsa/rsa.rb
index ece40c5..8dd2715 100644
--- a/ma5/rsa/rsa.rb
+++ b/ma5/rsa/rsa.rb
@@ -1,5 +1,5 @@
 module RSA
-	def self.mod_inv(a, m)
+	def self.n_inv(a, m)
 		(1..m).each{|x| break x if (a*x % m == 1)}
 	end
 
@@ -9,16 +9,18 @@ module RSA
 			@n = p1 * p2
 			@phi = (p1-1)*(p2-1)
 
+			enc = []
 			(2...@phi).each do |e|
 				dom = e.gcd(@phi)
 
 				if dom == 1 then
-					@e = e
-					break
+					enc << e
 				end
 			end
+			@e = enc.sample
 
-			@d = RSA.mod_inv(@e, @n)
+			@d = RSA.n_inv(@e, @n)
+			puts "e=#{@e} d=#{@d}"
 		end
 
 		def pubkey
@@ -30,36 +32,59 @@ module RSA
 		end
 	end
 
-	class Data < Array
+	class Data 
 		attr_reader :data
 		def initialize(data)
-			super data
-			if data.class == String then
-				self = data.split("")
-				self = self.map do |c|
-					c.to_i
+			@data = data
+			if data.is_a? String then
+				@data = @data.split("").map do |c|
+					c.ord.to_i
 				end
 			end
+			puts "Generated bytearray: #{@data}"
 		end
 
-		def inspect
-			self.join " "
+		def raw
+			str = ""
+			@data.each do |byte|
+				str += "\\x#{byte.to_s 16}"
+			end
+			return str
+		end
+
+		def inspect(endchar="\n")
+			pattern = "c" * @data.length
+			return "# \'#{@data.pack(pattern)}\'#{endchar}"
 		end
 
-		def encrypt(key)
-			e, mod = key.pubkey
+		def encrypt(pubkey)
+			e, n = pubkey
 			crypt = []	
-			text.split("").each_with_index do |c, i|
-				c = c.ord ** e
-				c %= mod
-				crypt << charint
+			@data.each do |c|
+				cr = (c ** e) % n
+				crypt << cr
 			end
 
 			return crypt 
 		end
 
-		def encrypt!(key)
-			self = self.encrypt(key)
+		def decrypt(privkey)
+			d, n = privkey 
+			crypt = []	
+			@data.each do |c|
+				cr = (c ** d) % n
+				crypt << cr
+			end
+
+			return crypt 
+		end
+
+		def encrypt!(pubkey)
+			@data = self.encrypt(pubkey)
+		end
+
+		def decrypt!(privkey)
+			@data = self.decrypt(privkey)
 		end
 	end
 end
diff --git a/ma5/rsa/test.rb b/ma5/rsa/test.rb
new file mode 100755
index 0000000..787ffc3
--- /dev/null
+++ b/ma5/rsa/test.rb
@@ -0,0 +1,27 @@
+#!/usr/bin/ruby -w
+
+require_relative "rsa"
+
+Primes = File.read("primes.txt").chomp.split(",").map do |pstr|
+	pstr.to_i
+end
+
+puts "Fetching random primes..."
+p1, p2 = Primes.sample, Primes.sample
+p1, p2 = 11, 13
+puts "p1=#{p1}, p2=#{p2}"
+puts
+
+key = RSA::Key.new(p1, p2)
+print "Message to be encrypted: "
+msg = gets.chomp
+
+data = RSA::Data.new(msg)
+
+data.encrypt!(key.pubkey)
+puts "Encrypted bytes: #{data.raw}"
+
+data.decrypt!(key.privkey)
+puts data.raw
+p data.data
+