Matasano Crypto

matasano.go

package main

import (
	"fmt"
	"encoding/hex"
	"encoding/base64"	
)

func main() {
	s := "1c0111001f010100061a024b53535009181c"
	t := "686974207468652062756c6c277320657965"
	fmt.Println(fixedXOR(s, u))
}

// set 1 - Challenge 1
// Usage: Returns a base64 encoded version of a hex encoded string
func hexToBase64(s string) string {
	h, err := hex.DecodeString(s) //[]byte
	if err != nil {
		fmt.Println("Error: ", err)
	}
	return base64.StdEncoding.EncodeToString(h)
}

// set 1 - Challenge 2
// LESSON: a ^ b = c; c ^ a = b; b ^ c = a
// Usage: Finds the xor between two hex encoded strings
func fixedXOR(s string, t string) string {
	a, _ := hex.DecodeString(s)
	b, _ := hex.DecodeString(t)
	x := make([]byte, len(a))
	for i := 0; i < len(a); i++ {
		x[i] = a[i] ^ b[i]
	}
	return hex.EncodeToString(x)
}