pcdinh

import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.net.StandardSocketOptions;
import java.nio.ByteBuffer;
import java.nio.channels.CancelledKeyException;
import java.nio.channels.ReadableByteChannel;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;

pcdinh

import smtplib
from email.MIMEMultipart import MIMEMultipart
from email.MIMEBase import MIMEBase
from email.MIMEText import MIMEText
from email.Utils import COMMASPACE, formatdate
from email import Encoders
import os
import time
import random

pcdinh

class MyHTTPServer(tornado.httpserver.HTTPServer):
    _stopped = False

    def _quit_if_ioloop_is_empty(self):
        ioloop = tornado.ioloop.IOLoop.instance()
        if len(ioloop._handlers) <= 1:
            logger.info("Graceful shutdown complete. Exiting!")
            exit(0)
        else:
            logger.info("Waiting for ioloop to be empty. has %d handlers left" % len(ioloop._handlers))

pcdinh

#!/usr/bin/env bash

# Works fine on Ubuntu 14.0.4 LTS

NGINX_VERSION="1.9.9"
NCHAN_VERSION="0.97"
HEADERS_MORE_VERSION="0.29"
DEV_KIT_VERSION="0.2.19"
ECHO_VERSION="0.58"
FANCY_INDEX_VERSION="0.3.5"

pcdinh

Okay so here's the setup:

[-] The primary server API is exposed via Flask (Python) and all static files, including all html, css, js is served by nginx. 
[-] Python is exposing an API at url http://domain.com/api/download/<file_id>, where file_id is a database id for the file that we're interested in downloading. 

1. User wants to download a file, so we spawn a new window with the url '/api/download/<file_id>'
2. Nginx intercepts the request, sees that it starts with /api/, and then forwards the request to Flask, which is being served on port 5000. 
3. Flask routes the request to its download method, retrieves the pertinent data from the file_id, and constructs additional header settings to make nginx happy and to force the browser to see the file stream as a download request instead of the browser just trying to open the file in a new window. Flask then returns the modified header stream to nginx
4. Nginx is finally ready to do some work. While parsing the headers for the incoming request, it encounters "X

pcdinh

O(1) Block Propagation

The problem

Bitcoin miners want their newly-found blocks to propagate across the network as quickly as possible, because every millisecond of delay increases the chances that another block, found at about the same time, wins the "block race."

pcdinh

wget http://openresty.org/download/ngx_openresty-1.7.10.1.tar.gz \
    -O ngx_openresty-1.7.10.1.tar.gz

tar xzvf ngx_openresty-1.7.10.1.tar.gz
cd ngx_openresty-1.7.10.1
./configure
make
sudo make install

wget https://codeload.github.com/keplerproject/luarocks/tar.gz/v2.0.13 \

pcdinh

http {
    log_format  filt  '$remote_addr - $remote_user [$time_local] "$_request" '
                      '$status $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "$http_x_forwarded_for"';

    server {
        
        location /login {
          # `set` is provided by the Rewrite module
          set $filter "password|secret";

pcdinh

# using such a setup requires `apt-get install lua-nginx-redis` under Ubuntu Trusty
# more info @ http://wiki.nginx.org/HttpLuaModule#access_by_lua

http {
  lua_package_path "/etc/nginx/include.d/?.lua;;";
  lua_socket_pool_size 100;
  lua_socket_connect_timeout 10ms;
  lua_socket_read_timeout 10ms;
  
  server {

pcdinh

Semiprivate Keys

Semi-private keys are an expansion of the traditional idea of asymmetric keys, which have a public/private keypair, to N keys which can each represent a different capability level. In the degenerate case, a semi-private key system has 3 different types of keys. These are, to use the Tahoe terminology:

• writecap: can publish new ciphertexts
• readcap: can read/authenticate ciphertexts