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@christoofar
christoofar / main.md
Last active May 14, 2024 04:16
Wrapping a C library call in a defensive Go routine
This study focuses on the strategies used by the "xz backdoor", an extremely
complex piece of malware that contains its own x64 disassembler inside of it 
to find critical locations in your code and hijacks it by swapping out your 
code with its own as it runs.  Because this a machine-code based attack,
all code written in any program language can be attacked and is vulnerable.

Instead of targeting sshd directly, the xz 
backdoor injects itself in the parent systemd process then hijacks the 
GNU Dynamic Linker (ld), before sshd is even started or libcrypto.so is 
@dsafreno
dsafreno / firebase-hook.js
Created January 14, 2020 16:52
React Hooks for loading Firebase Data
import React, { useReducer, useEffect, useRef } from 'react';
import firebase from 'firebase/app';
import equal from 'deep-equal';
function filterKeys(raw, allowed) {
if (!raw) {
return raw;
}
let s = new Set(allowed);
return Object.keys(raw)
@undefinedbehavior
undefinedbehavior / rpi3_rust_led.rs
Last active January 17, 2017 06:47
Rust demo for Pi 3 bare metal
#![feature(asm)]
#![feature(lang_items)]
#![crate_type = "staticlib"]
#![no_std]
const GPIO_BASE: u32 = 0x3F200000; // base address for Pi 2 and Pi 3
fn sleep(value: u32){
for _ in 1..value {
unsafe { asm!("");}
@mfuerstenau
mfuerstenau / zigzag-encoding.README
Last active July 1, 2024 17:19
ZigZag encoding/decoding explained
ZigZag-Encoding
---------------
Maps negative values to positive values while going back and
forth (0 = 0, -1 = 1, 1 = 2, -2 = 3, 2 = 4, -3 = 5, 3 = 6 ...)
(i >> bitlength-1) ^ (i << 1)
with "i" being the number to be encoded, "^" being
XOR-operation and ">>" would be arithemtic shifting-operation
@olivierlacan
olivierlacan / migrate_postgresql_database.md
Last active March 24, 2022 20:30
How to migrate a Homebrew-installed PostgreSQL database to a new major version (9.3 to 9.4) on OS X. See upgraded version of this guide: http://olivierlacan.com/posts/migrating-homebrew-postgres-to-a-new-version/

This guide assumes that you recently run brew upgrade postgresql and discovered to your dismay that you accidentally bumped from one major version to another: say 9.3.x to 9.4.x. Yes, that is a major version bump in PG land.

First let's check something.

brew info postgresql

The top of what gets printed as a result is the most important:

@gubatron
gubatron / compiling_building_c_cpp_notes.md
Last active April 18, 2024 07:58
Things to remember when compiling and linking C/C++ programs

Things to remember when compiling/linking C/C++ software

by Angel Leon. March 17, 2015;

Last update on December 14, 2023

Updated on February 27, 2023

Updated August 29, 2019.

@webcss
webcss / mithril-touch.js
Last active May 26, 2020 15:34
mithril-touch, consume touch and mouse events evenly with mithril
/*****************************************
/* DOM touch support module
/*****************************************/
if (!window.CustomEvent) {
window.CustomEvent = function (event, params) {
params = params || { bubbles: false, cancelable: false, detail: undefined };
var evt = document.createEvent('CustomEvent');
evt.initCustomEvent(event, params.bubbles, params.cancelable, params.detail);
return evt;
};