schrodyn

Replacing the CenturyLink provided ethernet router with OpenBSD

Unfortunately CenturyLink provisions their fiber to the home with a PPPoE authentication over vlan 201, this makes replacing the router more difficult than it should be. I also had to call CenturyLink support to get the password for the PPPoE connection.

cnmac0 is the egress interface on my EdgeRouter Lite.

You also need to add match on pppoe0 scrub (max-mss 1440)

schrodyn

Welcome to Jordan's grab-bag of common Binary Ninja Snippets.

These snippest are meant to run with the Binary Ninja Snippets Plugin
(http://github.com/Vector35/snippets) though they can all also be pasted
directly into the python console or turned into stand-alone plugins if needed.

To install the entire collection at once, just install the Snippets plugin via
the plugin manager (CMD/CTL-SHIFT-M), confirm the Snippet Editor works
(Tool/Snippets/Snippet Editor), and unzip this bundle (Download ZIP above) into
your Snippets folder.

schrodyn

ELF Format Cheatsheet

Introduction

Executable and Linkable Format (ELF), is the default binary format on Linux-based systems.

Compilation

schrodyn

About

• I faced bandwidth issues between a WG Peer and a WG server. Download bandwidth when downloading from WG Server to WG peer was reduced significantly and upload bandwidth was practically non existent.
• I found a few reddit posts that said that we need to choose the right MTU. So I wrote a script to find an optimal MTU.
• Ideally I would have liked to have run all possible MTU configurations for both WG Server and WG Peer but for simplicity I choose to fix the WG Server to the original 1420 MTU and tried all MTUs from 1280 to 1500 for the WG Peer.

Testing

• On WG server, I started an iperf3 server
• On WG peer, I wrote a script that does the following:
  • wg-quick down wg0
• Edit MTU in the /etc/wireguard/wg0.conf file

schrodyn

#!/usr/bin/env python
import argparse
import binascii
import hashlib
import os
import re
import sys
import traceback

__author__  = "Jeff White [karttoon] @noottrak"

schrodyn

!pe
.exr -1 `last exception
!sos.pe `last clr exception
!dso  `dump stack object
.chain 

.load sos

schrodyn

NEWLINE=$'\n'
PROMPT="[%(?:%{$fg_bold[green]%}quack :%{$fg_bold[red]%}quack )%{$reset_color%}(%T) "
PROMPT+='%{$fg[cyan]%}%c%{$reset_color%}$(git_prompt_info)'
PROMPT+="]${NEWLINE}"
PROMPT+="➜ "

ZSH_THEME_GIT_PROMPT_PREFIX=" %{$fg_bold[blue]%}git:(%{$fg[red]%}"
ZSH_THEME_GIT_PROMPT_SUFFIX="%{$reset_color%}"
ZSH_THEME_GIT_PROMPT_DIRTY="%{$fg[blue]%}) %{$fg[yellow]%}✗"
ZSH_THEME_GIT_PROMPT_CLEAN="%{$fg[blue]%})"

schrodyn

• macOS, Zsh, and more
  • Zsh initializations
  • Zsh way of $PATH
  • the special macOS
  • /usr/libexec/path_helper
    • What is it?
    • What does it do?
    • What does it break?
  • Situation explained

• The .*shrc file

schrodyn

import time
from typing import List
import pefile
from capstone import *
from capstone.x86 import *
import re
import struct

# SAMPLE_PATH = 'bin/enc_string_test.bin32'
SAMPLE_PATH = 'bin/2cd2f077ca597ad0ef234a357ea71558d5e039da9df9958d0b8bd0efa92e74c9.bin32'

schrodyn

I run this on my server called 'empty'.

Assuming you've done a git clone or a git pull of the code...

Switch to the release you want to build:

[dan@empty:~/librenms] $ export RELEASE=1.56
[dan@empty:~/librenms] $ git checkout master
[dan@empty:~/librenms] $ git pull
[dan@empty:~/librenms] $ git checkout tags/$RELEASE