crowell

using System;
using System.Drawing;
using SdlDotNet.Graphics;
using SdlDotNet.Core;
using SdlDotNet.Input;
using System.IO.Ports; //connection to the Arduino
using System.Text; //stringbuilder
using System.Data;

crowell

#include <iostream>
#include <cstring>
#include <cstdio>
#include <string>
#include <map>
#include "getpost.h"
#include <sys/resource.h>
 
using namespace std;

crowell

import math

N = 15241559823203705227878887673081037716739857612370054905916497747890512048310998045508373462474562762403971294892047440113259277270082256942002416995850675202397184299808987
e = 13

def mysqrt(x):
    if x < 0:
        raise ValueError('square root not defined for negative numbers')
    n = int(x)
    if n == 0:

crowell

import math
import fractions
N = 1791144786733299256875903974696580801523488563758757235898102851290189765401005609588035532773568199
e = 3

def gcd_iter(u, v):
    while v:
        u, v = v, u % v
    return abs(u)

crowell

import math
import fractions
N = 1791144786733299256875903974696580801523488563758757235898102851290189765401005609588035532773568199
e = 3

def gcd_iter(u, v):
    while v:
        u, v = v, u % v
    return abs(u)

crowell

import math

N = 257604469245070482680978550578686065374289166183513000923532857227284294429858993942954469559591983
e = 3
d = 85868156415023494226992850192895355124763055394504333641177619075761431476619664647651489853197328

def mysqrt(x):
    if x < 0:
        raise ValueError('square root not defined for negative numbers')
    n = int(x)

crowell

require 'httparty'
require 'colorize'
require 'highline/import'
require 'json'

class GitHub
    def getToken
        puts "[!] GitHub API Token needed to use gists".red
        _username = ask("USERNAME: ".green) {|q| q.echo = true}
        _password = ask("PASSWORD: ".green) {|q| q.echo = false}

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// De Bruijn pattern generator.
// Jeffrey Crowell

#include "debruijn.h"

char* peda_charset =
    "A%sB$nC-(D;)Ea0Fb1Gc2Hd3Ie4Jf5Kg6Lh7Mi8Nj9OkPlQmRnSoTpUqVrWsXtYuZvwxyz";

// Generate a De Bruijn sequence. Code interpreted from wikipedia.
void db(int t, int p, int n, int maxlen, int k, int* a, char* sequence,

crowell

radare2 is a very cool set of tools that you probably don't know how to use! Let's go through a simple exploit CTF challenge to understand how to use it for exploit development.

We'll be focusing on "ropasaurus rex" which is a simple challenge from Plaid CTF After checking out the latest and greatest radare from git, let's get started!

Open up ropasaurusrex in r2 and call analyze on the binary. We can list the functions with "afl"

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# Poker II Firmware disassembly help tool.

original = IO.read("./Poker II original firmware.bin")
extracted = ""
original.each_byte{|b|
  m = (((b & 0x0f) << 4) | ((b & 0xf0) >> 4)) ^ 0xff
  extracted << m.chr
}
puts extracted