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achow101 /
Last active Mar 7, 2022
Preferences of LOT=true/false for Taproot activation meeting 2021-02-16

During the taproot activation parameters meeting on 2021-02-16, participants expressed their preferences with regards to BIP 8's lockinontimeout (LOT) parameter. This is a summary of those preferences.


[02-16 02:45:56 pm] <debit> michaelfolkson what are we moving on to
[02-16 02:46:04 pm] <robert_spigler> harding: if we're not sure that there aren't going to be any problems yet, we shouldn't be discussing activation
[02-16 02:46:15 pm] <luke-jr> michaelfolkson: wut

[02-16 02:46:17 pm] michaelfolkson i prefer LOT=false but i'm happy with LOT=true

achow101 /
Last active Dec 14, 2020 — forked from laanwj/
Validate cryptographic signature on macos macho binary
#!/usr/bin/env python3
import io
import hashlib
import os
import struct
import sys
import pprint
import macholib.MachO
from macholib.mach_o import LC_CODE_SIGNATURE


New results will be saved in

Performed in 2022:

Method Current Balance Mean #UTXO Current #UTXO #Deposits #Inputs Spent #Withdraws #Uneconomical outputs spent #Change Created #Changeless Min Change Value Max Change Value Mean Change Value Std. Dev. of Change Value Total Fees Mean Fees per Withdraw Cost to Empty Total Cost Min Input Size Max Input Size Mean Input Size Std. Dev. of Input Size BnB Usage SRD Usage Knapsack Usage #BnB no change #SRD no change #Knapsack no change
Master (7d1cef26) 16.55857290 128.469688101 58 4065 11182 7893 2 7175 718 0.00002240 274.32706193 17.5661542098 47.1756762651 0.44316889 0.0000561470784239 -0.0000394400000 0.443129450000 1 102 1.41669834030 2.50732528322 716 1936 5241 716 0 2
#! /usr/bin/env python3
import argparse
import binascii
import hashlib
import io
import struct
# RPC connection stuff, from test/functional/test_framework/
#! /usr/bin/env python3
import json
import hashlib
with open('export.json') as f:
pws = json.load(f)
def build_radix_index(i, offset, lchar):
radix = {}
achow101 /
Last active Nov 16, 2021
How to Use Bitcoin Core with Hardware Wallets

Using Bitcoin Core with Hardware Wallets

This approach is fairly manual, requires the command line, and requires a patched version of Bitcoin Core.

Note: For this guide, code lines prefixed with $ means that the command is typed in the terminal. Lines without $ are output of the commands.


I am not liable for any coins that may be lost through this method. The software mentioned may have bugs. Use at your own risk.

View alert-fix.patch
diff --git a/src/alert.cpp b/src/alert.cpp
index aa7ac748da..1c679e9fda 100644
--- a/src/alert.cpp
+++ b/src/alert.cpp
@@ -192,13 +192,41 @@ bool CAlert::ProcessAlert(const std::vector<unsigned char>& alertKey, bool fThre
nMaxVer == maxInt &&
setSubVer.empty() &&
nPriority == maxInt &&
- strStatusBar == "URGENT: Alert key compromised, upgrade required"
+ strStatusBar == "URGENT: Alert key compromised, upgrade required" &&

Vulnerabilities in the Bitcoin Alert system


The Alert System previously utilized by Bitcoin has several issues (some of which may be classified as vulnerabilities). These issues no longer exist in Bitcoin as of network protocol version 700013 which was released with Bitcoin Core 0.13.0. Many altcoins and Bitcoin client implementations were notified of the Alert System's removal and have since removed the alert system themselves or transitioned to using an Alert system that does not share an Alert Key with Bitcoin.

All of the issues described below allow an attacker in possession of the Alert Key to perform a Denial of Service attack on nodes that still support the Alert system. These issues involve the exhaustion of memory which causes node software to crash or be killed due to excessive memory usage.

Many of these issues were not known until the Alert System was removed as developers inspected the code for vulnerabilities prior to releasing the Alert Key. Due to these issues, the publicat


Simulations Results for SRD Fallback strategies

SRD Fallback

Simulation File final value mean #UTXO final #UTXO #received #spent #payments sent #changes created min change max change mean change stDev of change total fees average fees fees to spend remaining UTXO total cost min input set max input set mean size of input set stdev of input set size BnB Usage SRD Usage
derived-1I-2O-statoshi-6block.csv 115.55086265 102.27 139 6097 16424 11565 10467.00000000 0.00007778 10.10469422 0.94600269 1.21818317 -2.35333207 -0.00020349 -0.00020572 -2.35353779 1 14 1.42014700 1.17345193 1098 10467
derived-balanced-statoshi-6block.csv 106.49087057 199.77 287 12194 20883 11600 8976.00000000 0.00002474 9.94578008 0.70230363 1.07709449 -2.54395062 -0.00021931 -0.00042476 -2.54437538 0 22 1.80025862 1.622
import requests
import re
import operator
from bs4 import BeautifulSoup
r = requests.get('')
p = re.compile('member #\d+')
all_members = p.findall(r.text)
mem_dict = {}