Kevin Pan bitkevin

Blockchain Rule Update Process

We recently rolled out two changes to the Bitcoin block acceptance rules (BIP16 and BIP30); this document records the lessons learned and makes recommendations for handling future blockchain rule changes.

Note: there are "soft" rule changes and "hard" rule changes. "Soft" changes tighten up the rules-- old software will accept all the blocks and transactions created by new software, but the opposite may not be true. "Soft" changes do not require the entire network of miners and merchants and users to upgrade or be left behind.

"Hard" changes modify the rules in a way that old, un-upgraded software consider illegal. At this point it is much, much more difficult (some might say impossible) to roll out "hard" changes, because they require every miner and merchant and user to upgrade.

Lessons Learned

bitcoin address validation

http://rosettacode.org/wiki/Bitcoin/address_validation

C

#include <stdio.h>
#include <string.h>
#include <openssl/sha.h>

Prereq:

apt-get install zsh
apt-get install git-core

Getting zsh to work in ubuntu is weird, since sh does not understand the source command. So, you do this to install zsh

wget https://github.com/robbyrussell/oh-my-zsh/raw/master/tools/install.sh -O - | zsh

WR703N OpenWrt 配置流程

下载安装

访问WR703N在OpenWrt的[Wiki页][wr703n-openwrt]，然后在Flashing一节中找到下载链接：[squashfs-factory.bin][flash.bin]，下载后别忘了[比对md5][md5sum]。^[1]

进入路由器管理界面，出厂配置为http://192.168.1.1，用户名和密码均为admin，然后进入固件更新，选择下载的文件，然后更新。

Abstract

This document specifies proposed changes to the Bitcoin transaction validity rules in order to make malleability of transactions impossible (at least when the sender doesn't choose to avoid it).

Motivation

As of february 2014, Bitcoin transactions are malleable in multiple ways. This means a (valid) transaction can be modified in-flight, without invalidating it, but without access to the relevant private keys.

This is a problem for multiple reasons:

The sender may not recognize his own transaction after being modified.

WR703N OpenWrt 配置流程

下载安装

访问WR703N在OpenWrt的[Wiki页][wr703n-openwrt]，然后在Flashing一节中找到下载链接：[squashfs-factory.bin][flash.bin]，下载后别忘了[比对md5][md5sum]。^[1]

进入路由器管理界面，出厂配置为http://192.168.1.1，用户名和密码均为admin，然后进入固件更新，选择下载的文件，然后更新。

	# Raw transaction API example work-through
	# Send coins to a 2-of-3 multisig, then spend them.
	#
	# For this example, I'm using these three keypairs (public/private)
	# 0491bba2510912a5bd37da1fb5b1673010e43d2c6d812c514e91bfa9f2eb129e1c183329db55bd868e209aac2fbc02cb33d98fe74bf23f0c235d6126b1d8334f86 / 5JaTXbAUmfPYZFRwrYaALK48fN6sFJp4rHqq2QSXs8ucfpE4yQU
	# 04865c40293a680cb9c020e7b1e106d8c1916d3cef99aa431a56d253e69256dac09ef122b1a986818a7cb624532f062c1d1f8722084861c5c3291ccffef4ec6874 / 5Jb7fCeh1Wtm4yBBg3q3XbT6B525i17kVhy3vMC9AqfR6FH2qGk
	# 048d2455d2403e08708fc1f556002f1b6cd83f992d085097f9974ab08a28838f07896fbab08f39495e15fa6fad6edbfb1e754e35fa1c7844c41f322a1863d46213 / 5JFjmGo5Fww9p8gvx48qBYDJNAzR9pmH5S389axMtDyPT8ddqmw

	# First: combine the three keys into a multisig address:
	./bitcoind createmultisig 2 '["0491bba2510912a5bd37da1fb5b1673010e43d2c6d812c514e91bfa9f2eb129e1c183329db55bd868e209aac2fbc02cb33d98fe74bf23f0c235d6126b1d8334f86","04865c40293a680cb9c020e7b1e106d8c1916d3cef99aa431a56d253e69256dac09ef122b1a9

	# -- Mode: Python --

	# OpenSSL wrapper
	# https://github.com/joric/brutus/blob/master/ecdsa_ssl.py

	import ctypes
	import ctypes.util

	ssl = ctypes.cdll.LoadLibrary (ctypes.util.find_library ('ssl') or 'libeay32')

	// g++ UniversalTimer.o BinaryData.o FileDataPtr.o BtcUtils.o BlockObj.o BlockUtils.o libcryptopp.a -o bootstrap.out -Icryptopp -DUSE_CRYPTOPP -D__STDC_LIMIT_MACROS -lpthread bootstrap.cpp

	#include "BlockUtils.h"

	int main(void)
	{
	string btcdir("/home/chris/.bitcoin");
	string bootstrap(btcdir + "/" + "bootstrap.dat");
	BlockDataManager_FileRefs::GetInstance().SelectNetwork("Main");
	BlockDataManager_FileRefs & bdm = BlockDataManager_FileRefs::GetInstance();

	#ifndef LIBEVENT_CONNECTIONH
	#define LIBEVENT_CONNECTIONH

	extern "C" {
	#include <event2/event.h>
	#include <event2/buffer.h>
	#include <event2/bufferevent.h>
	}
	#include <string>