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@colindean
colindean / generate_bitcoin_address.sh
Last active October 12, 2023 23:45
Bitcoin address generator in bash
#!/bin/bash
#
# This is free and unencumbered software released into the public domain.
#
# Requires bc, dc, openssl, xxd
#
# by grondilu from https://bitcointalk.org/index.php?topic=10970.msg156708#msg156708
base58=({1..9} {A..H} {J..N} {P..Z} {a..k} {m..z})
bitcoinregex="^[$(printf "%s" "${base58[@]}")]{34}$"
@jppommet
jppommet / int2ip.js
Last active December 26, 2023 13:44
javascript conversion from ip address to long integer and vice versa
function int2ip (ipInt) {
return ( (ipInt>>>24) +'.' + (ipInt>>16 & 255) +'.' + (ipInt>>8 & 255) +'.' + (ipInt & 255) );
}
@albrow
albrow / IpToDecimal.js
Last active March 3, 2021 14:46
A short javascript function to convert an IP address in dotted decimal notation to a regular decimal. This is useful for IP address geolocation lookups. Supports both IPv4 and IPv6 addresses. http://en.wikipedia.org/wiki/Ip_address
// convert the ip address to a decimal
// assumes dotted decimal format for input
function convertIpToDecimal(ip) {
// a not-perfect regex for checking a valid ip address
// It checks for (1) 4 numbers between 0 and 3 digits each separated by dots (IPv4)
// or (2) 6 numbers between 0 and 3 digits each separated by dots (IPv6)
var ipAddressRegEx = /^(\d{0,3}\.){3}.(\d{0,3})$|^(\d{0,3}\.){5}.(\d{0,3})$/;
var valid = ipAddressRegEx.test(ip);
if (!valid) {
return false;
@sivel
sivel / better-ssh-authorized-keys-management.md
Last active May 3, 2024 14:20
Better SSH Authorized Keys Management

Better SSH Authorized Keys Management

A seemingly common problem that people encounter is how to handle all of your users authorized_keys file.

People struggle over management, ensuring that users only have specific keys in the authorized_keys file or even a method for expiring keys. A centralized key management system could help provide all of this functionality with a little scripting.

One piece of functionality overlooked in OpenSSH is the AuthorizedKeysCommand configuration keyword. This configuration allows you to specify a command that will run during login to retrieve a users public key file from a remote source and perform validation just as if the authorized_keys file was local.

Here is an example directory structure for a set of users with SSH public keys that can be shared out via a web server:

@oscarmorrison
oscarmorrison / IFTTTDate.md
Last active December 3, 2023 21:44
Make IFTTT Date Format play nice with Google Spreadsheets

##Date and Time

=TIMEVALUE(SUBSTITUTE("{{OccurredAt}}"," at ", " ")) + DATEVALUE(SUBSTITUTE("{{OccurredAt}}"," at ", " "))

##Date

=DATEVALUE(SUBSTITUTE("{{OccurredAt}}"," at ", " "))

##Time

@briankip
briankip / binwalk.md
Last active May 8, 2024 13:51
A short introduction to binwalk

Binwalk

Binwalk is a simple linux tool for analysing binary files for embeded files and executable code. It is mostly used to extract the content of firmware images.

Installation

On kali linux, binwalk is already installed. On ubuntu you can do apt-get install binwalk or you can go to https://github.com/devttys0/binwalk and follow the instructions.

Usage

@MichaelPote
MichaelPote / himawari.ps1
Created February 3, 2016 19:11
Windows Powershell Script to download the latest image from the Himawari-8 satelite, combine the tiles into a single image, convert to jpg and then set as the desktop background.
#
# Himawari-8 Downloader
#
#
#
# This script will scrape the latest image from the Himawari-8 satellite, recombining the tiled image,
# converting it to a JPG which is saved in My Pictures\Himawari\ and then set as the desktop background.
#
# http://himawari8.nict.go.jp/himawari8-image.htm
#
@cyrusboadway
cyrusboadway / google-domains-dynamic-dns-update.sh
Created February 20, 2016 17:21
Script to update a Google Domains DNS record
#!/bin/bash
### Google Domains provides an API to update a DNS "Syntheitc record". This script
### updates a record with the script-runner's public IP, as resolved using a DNS
### lookup.
###
### Google Dynamic DNS: https://support.google.com/domains/answer/6147083
### Synthetic Records: https://support.google.com/domains/answer/6069273
USERNAME=""
import {connect} from 'react-redux'
export const reduxify = (container) =>
connect(
container.mapStateToProps,
container.mapDispatchToProps,
)(container.render)
@ExtremeGTX
ExtremeGTX / Ubuntu_AP.md
Last active May 29, 2024 07:27
Setup Ubuntu server as Access point

Introduction

This tutorial for setting up Ubuntu Server (RPi 3B) as Wifi access point

Overview:

The main steps can be listed as following:

  1. Install required packages
  2. Setup hostapd
  3. Setup DNSmasq
  4. Configure AP IP Address