Skip to content

Instantly share code, notes, and snippets.

View vkobel's full-sized avatar

Vincent Kobel vkobel

51 followers · 19 following
View GitHub Profile
@vkobel
vkobel / _toy_ecdsa.py
Last active August 16, 2024 14:27
Toy ECDSA implementation (no deps) -- education purposes only, do NOT use in prod
import hashlib
import secrets
# Parameters for the secp256k1 curve
p = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2F
a = 0
b = 7
Gx = 0x79BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798
Gy = 0x483ADA7726A3C4655DA4FBFC0E1108A8FD17B448A68554199C47D08FFB10D4B8
n = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141
@vkobel
vkobel / incremental_merkle.py
Last active June 21, 2024 11:17
Short incremental Merkle Tree python implementation
import hashlib
import random
class IncrementalMerkleTree:
def __init__(self, depth: int) -> None:
if depth < 1:
raise ValueError("Depth must be at least 1")
self.depth: int = depth
self.leaf_count: int = 2 ** depth
@vkobel
vkobel / permit-signer.html
Created December 21, 2023 15:29
Web3 signer for the EIP-20 Permit method
<!DOCTYPE html>
<html>
<head>
<title>ERC20 Permit Signing</title>
<script src="https://cdn.jsdelivr.net/npm/web3/dist/web3.min.js"></script>
</head>
<style>
body {
@vkobel
vkobel / hash_kernel_module.c
Last active December 2, 2024 13:24
Example of using the Linux Kernel Crypto API for SHA256 hashing (tested with 5.6)
#include <linux/module.h>
#include <crypto/hash.h>
struct sdesc {
struct shash_desc shash;
char ctx[];
};
static struct sdesc *init_sdesc(struct crypto_shash *alg)
{
@vkobel
vkobel / kernel_rootkit.c
Last active October 22, 2022 16:54
Simple "rootkit" kernel module (tested with Linux 5.6.3) that adds a device handler taking a PID and upgrade it to root (example in the comments below)
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/cred.h>
#include <linux/fs.h>
MODULE_LICENSE("GPL");
struct task_struct *get_task_struct_by_pid(unsigned pid)
{
struct pid *proc_pid = find_vpid(pid);
@vkobel
vkobel / init.vim
Created September 7, 2019 11:31
my vim configuration (nvim)
❯ ccat ~/.config/nvim/init.vim
" ======================
" Plugins are define here
" ======================
call plug#begin('~/.vim/plugged')
Plug 'Valloric/YouCompleteMe'
Plug 'scrooloose/nerdtree'
Plug 'drewtempelmeyer/palenight.vim'
Plug 'itchyny/lightline.vim'
@vkobel
vkobel / 21-yubikey.rules
Last active July 25, 2019 14:38
YubiKey lock screen when unplugged
## /etc/udev/rules.d/21-yubikey.rules
ACTION=="remove", SUBSYSTEM=="input", ATTRS{idVendor}=="1050", ATTRS{idProduct}=="0407", RUN+="/usr/local/bin/lockscreen.sh"
@vkobel
vkobel / patchfile.diff
Last active May 23, 2019 16:21
paramiko crypto remove warnings patch for master(cf7d49d66f3b1fbc8b0853518a54050182b3b5eb)
diff --git a/ecdsakey.py b/ecdsakey.py
index b73a969e..353c5f9e 100644
--- a/ecdsakey.py
+++ b/ecdsakey.py
@@ -160,12 +160,12 @@ class ECDSAKey(PKey):
pointinfo = msg.get_binary()
try:
- numbers = ec.EllipticCurvePublicNumbers.from_encoded_point(
+ key = ec.EllipticCurvePublicKey.from_encoded_point(
@vkobel
vkobel / wg0-client1.conf
Created June 23, 2018 16:59
Wireguard config example (VPN home)
[Interface]
Address = 10.0.0.2/24
PrivateKey = <Client 1 Priv Key>
[Peer]
PublicKey = <Server Pub Key>
Endpoint = <Server Public IP>:51820
AllowedIPs = 0.0.0.0/0
PersistentKeepalive = 25
@vkobel
vkobel / keybase.md
Created June 4, 2018 08:36

Keybase proof

I hereby claim:

  • I am vkobel on github.
  • I am kob (https://keybase.io/kob) on keybase.
  • I have a public key ASC--Xup1G4N3kXzgP9dyVqlpN2T0Nnc6_K1ds9K7uh4ZAo

To claim this, I am signing this object: