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@acutmore
acutmore / README.md
Last active January 21, 2024 20:30
Emulating a 4-Bit Virtual Machine in (TypeScript\JavaScript) (just Types no Script)

A compile-time 4-Bit Virtual Machine implemented in TypeScript's type system. Capable of running a sample 'FizzBuzz' program.

Syntax emits zero JavaScript.

type RESULT = VM<
  [
    ["push", N_1],         // 1
    ["push", False],       // 2
 ["peek", _], // 3
@shafik
shafik / WhatIsStrictAliasingAndWhyDoWeCare.md
Last active June 27, 2024 11:24
What is Strict Aliasing and Why do we Care?

What is the Strict Aliasing Rule and Why do we care?

(OR Type Punning, Undefined Behavior and Alignment, Oh My!)

What is strict aliasing? First we will describe what is aliasing and then we can learn what being strict about it means.

In C and C++ aliasing has to do with what expression types we are allowed to access stored values through. In both C and C++ the standard specifies which expression types are allowed to alias which types. The compiler and optimizer are allowed to assume we follow the aliasing rules strictly, hence the term strict aliasing rule. If we attempt to access a value using a type not allowed it is classified as undefined behavior(UB). Once we have undefined behavior all bets are off, the results of our program are no longer reliable.

Unfortunately with strict aliasing violations, we will often obtain the results we expect, leaving the possibility the a future version of a compiler with a new optimization will break code we th

@htp
htp / curl-websocket.sh
Last active May 14, 2024 21:24
Test a WebSocket using curl.
curl --include \
--no-buffer \
--header "Connection: Upgrade" \
--header "Upgrade: websocket" \
--header "Host: example.com:80" \
--header "Origin: http://example.com:80" \
--header "Sec-WebSocket-Key: SGVsbG8sIHdvcmxkIQ==" \
--header "Sec-WebSocket-Version: 13" \
http://example.com:80/
@joepie91
joepie91 / vpn.md
Last active June 29, 2024 17:36
Don't use VPN services.

Don't use VPN services.

No, seriously, don't. You're probably reading this because you've asked what VPN service to use, and this is the answer.

Note: The content in this post does not apply to using VPN for their intended purpose; that is, as a virtual private (internal) network. It only applies to using it as a glorified proxy, which is what every third-party "VPN provider" does.

  • A Russian translation of this article can be found here, contributed by Timur Demin.
  • A Turkish translation can be found here, contributed by agyild.
  • There's also this article about VPN services, which is honestly better written (and has more cat pictures!) than my article.
@renancouto
renancouto / exploit-urls.md
Last active February 1, 2023 09:36
A collection of weird URLs that I think are used to exploit security vulnerabilities on web apps
  • /manager/html (Apache Tomcat)
  • http://123.249.24.233/POST_ip_port.php
  • /tmUnblock.cgi
  • /HNAP1/
  • /phpMyAdmin/scripts/setup.php (PHPMyAdmin)
  • /pma/scripts/setup.php
  • /myadmin/scripts/setup.php
  • /MyAdmin/scripts/setup.php
  • /vyvy/vyv/vy.php
  • /cgi-sys/php5
@carlosefonseca
carlosefonseca / sqlite2csv.sh
Created January 9, 2014 13:44
Exports all tables in a sqlite database to CSV.
#!/usr/bin/env bash
# obtains all data tables from database
TS=`sqlite3 $1 "SELECT tbl_name FROM sqlite_master WHERE type='table' and tbl_name not like 'sqlite_%';"`
# exports each table to csv
for T in $TS; do
sqlite3 $1 <<!
.headers on
@gfixler
gfixler / EasyJumpPreciseMotionAce.vim
Created July 24, 2012 01:14
A Vim take on Emacs' AceJump mode, itself based on Vim's PreciseJump and EasyMotion plugins
" ACEJUMP
" Based on emacs' AceJump feature (http://www.emacswiki.org/emacs/AceJump).
" AceJump based on these Vim plugins:
" EasyMotion (http://www.vim.org/scripts/script.php?script_id=3526)
" PreciseJump (http://www.vim.org/scripts/script.php?script_id=3437)
" Type AJ mapping, followed by a lower or uppercase letter.
" All words on the screen starting with that letter will have
" their first letters replaced with a sequential character.
" Type this character to jump to that word.