Bud

THIS PROJECT IS NOT MAINTAINED ANYMORE

A TLS terminator for superheroes.

What is bud?

Bud is a TLS terminating proxy, a babel fish decoding incoming TLS traffic and sending it in a plain text to your backend servers. Not only does it do this well, bud has a lot of useful features!

Why bud?

Asynchronous key/cert loading using the supplied servername extension (SNI)
Asynchronous selection of backend to balance (using SNI)
Asynchronous OCSP stapling
TLS ticket rotation across cluster of workers, or multi-machine cluster (needs separate utility to synchronize them, but the protocol is in-place)
Availability: marking backends as dead, reviving them after period of time
Multi-frontend mode of operation. Single bud instance might be bound to multiple different ports and interfaces
Proxyline support: both HAProxy format at custom BUD JSON format
X-Forwarded-For for first HTTP request, and custom frame for SPDY (soon HTTP2 too) connection
Multi-context mode of operation, each context is used for different server name. All TLS parameters may be redefined in the context
Support for simultaneous ECDSA and RSA certs and keys

Implementation details

Bud is implemented fully in C, with the exception to the tests which are running on [node.js][2]. The networking level is provided by [libuv][3], and the SSL implementation by [OpenSSL][4] 1.0.2h.

Install

Requirements

You must have gcc installed. Chances are that you do, but in case you don't:

# OSX
# Command Line Tools for Xcode: xcode-select --install,
# https://developer.apple.com/downloads, or Xcode

# SmartOS
[sudo] pkgin update
[sudo] pkgin install gcc47

# Ubuntu
[sudo] apt-get update
[sudo] apt-get install build-essential

Easy Install

Bud can easily be installed using npm

[sudo] npm install -g bud

This will install the command line tool bud. Optionally, you can build Bud from source with the steps below.

Build

Preparing:

npm install

Building:

gypkg build

The result will be located at: ./out/Release/bud.

Starting

To start bud - create a configuration file using this template and then:

bud --conf conf.json

Options

Usage: bud [options]

options:
  --version, -v              Print bud version
  --config PATH, -c PATH     Load JSON configuration
  --piped-config, -p         Load piped JSON configuration
  --default-config           Print default JSON config
  --daemon, -d               Daemonize process

Configuration

Bud uses [JSON][0] as the configuration format. Run bud --default-config to get the default configuration options (with comments and description below):

{
  // Number of workers to use, if 0 - only one process will be spawned.
  "workers": 1,

  // Timeout in ms after which workers will be restarted (if they die)
  "restart_timeout": 250,

  // Logging configuration
  "log": {
    // Minimum observable log level, possible values:
    // "debug", "notice", "info" (default), "warning", "fatal"
    "level": "info",

    // syslog facility to use, could be:
    // "auth", "cron", "kern", "lpr", "mail", "news", "syslog"
    // "deamon", "uucp", "local0", ... "local7"
    "facility": "user",

    // if true - logging will be printed to standard output
    "stdio": true,

    // if true - syslog will be used for logging
    "syslog": true
  },

  // Availability of the backend
  "availability": {
    // Maximum number of backend reconnects before giving up
    "max_retries": 5,

    // Time between retries
    "retry_interval": 250,

    // How long backend should not be responding until considered to be dead -- ms
    "death_timeout": 1000,

    // Timeout in ms after which it should be revived
    "revive_interval": 2500
  },

  // Frontend configuration (i.e. TLS/SSL server)
  "frontend": {
    "port": 1443,
    "host": "0.0.0.0",

    // Alternatively you may want to specify multiple address to bind server to
    // "interfaces": [
    //   { "port": 1443, "host": "1.1.1.1" },
    //   { "port": 1444, "host": "2.2.2.2" }
    // ],

    // tcp keepalive value (in seconds)
    "keepalive": 3600,

    // if true - server listed ciphers will be preferenced
    "server_preference": true,

    // Which protocol versions to support:
    // **optional**, default: "ssl23"
    // "ssl23" (implies tls1.*): "tls1", "tls1.1", "tls1.2"
    "security": "ssl23",

    // Path to default TLS certificate
    // NOTE: Could be an array of cert strings
    // e.g. ["-----BEGIN CERTIFICATE-----...", "-----BEGIN CERTIFICATE-----..."]
    "cert": "keys/cert.pem",

    // Path to default TLS private key
    // NOTE: Could be an array of keys as file paths or strings
    "key": "keys/key.pem",

    // **Optional** Passphrase for the private key
    // NOTE: Could be an array of passphrases
    "passphrase": null,

    // **Optional** Cipher suites to use
    // Bud defaults to:
    // "ECDHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA256:ECDHE-RSA-AES256-SHA256:DHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES256-GCM-SHA256:DHE-RSA-AES256-SHA256:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:AES256-GCM-SHA384:AES256-SHA256:AES128-GCM-SHA256:AES128-SHA256:AES128-SHA:DES-CBC3-SHA"
    "ciphers": null,

    // **Optional** ECDH Curve to use, defaults to `prime256v1
    "ecdh": "prime256v1",

    // **Optional** Path to DH parameters file
    // **Recommend** generate a file
    // openssl dhparam -out dh.key 3072
    "dh": null,

    // **Optional** Base64 encoded TLS session ticket key,
    // should decode into 48 raw bytes
    // **Recommend** Generate with:
    // node -pe "require('crypto').randomBytes(48).toString('base64')"
    //
    // **Important note**: it should not be generally set, OpenSSL will generate
    // a random value for it at start, and ticket rotation will change it after
    // some time anyway
    "ticket_key": "yzNUDktR5KmA4wX9g9kDSzEn...true randomness",

    // **Optional** Ticket timeout in seconds, default: 3600
    "ticket_timeout": 3600,

    // **Optional** Interval between rotating ticket keys.
    // NOTE: If you are deploying bud to many boxes - please contact me, I'll
    // explain how ticket may be rotated simulatenously on all of them
    "ticket_rotate": 3600,

    // **Optional** NPN protocols to advertise
    "npn": ["http/1.1", "http/1.0"],

    // NOTE: Better leave this default:

    // **Optional** Renegotiation window in seconds
    "reneg_window": 300,

    // **Optional** Maximum number of renegotiations in a window
    "reneg_limit": 3,

    // **Optional** Maximum size of TLS fragment
    "max_send_fragment": 1400,

    // **Optional** If false - close frontend connection on backend EOF
    "allow_half_open": false,

    // **Optional** If true - the clients will be requested to provide the cert
    "request_cert": true,

    // **Optional**: Either filename or array of PEM certificate chain that
    // should be used for validating client certs
    "ca": "filename"
    // "ca": [ "-----BEGIN CERTIFICATE----\n..." ]
  },

  // Balance tactic
  // **Optional** possible values: "roundrobin", "sni", or "on-fail"
  //
  // * "roundrobin" - on each new connection select next live backend
  // * "sni" - select backend list from either async sni or supplied contexts
  // * "on-fail" - select next backend in list only if the previous one is
  //   dead
  "balance": "roundrobin"

  // Unix-specific option, drop privileges after starting the process
  // **Recommend** Create a user and a group for bud.
  "user": null,
  "group": null,

  // Backend configuration (i.e. address of Cleartext server)
  "backend": [{
    "port": 8000,
    "host": "127.0.0.1",
    "keepalive": 3600,

    // if true - HAProxy compatible proxyline will be sent:
    // "PROXY TCP4 ... ... ... ..."
    // if "json":
    // 'BUD {"family":"TCP4","bud":{"host":"...","port":...},"peer":{...}'
    "proxyline": false,

    // if true:
    // - if NPN is enabled and either `spdy/3.1`, `spdy/3` or `spdy/2` is
    //   negotiated - custom `X_FORWARDED` frame will be sent on connection.
    //   see: https://groups.google.com/forum/#!topic/spdy-dev/XkdtuShtVCEadds
    //
    // - in all other cases `X-Forwarded-For: <address>` will be added right
    //   after the first line in the incoming data.
    //
    // - in order to avoid parsing each request, the `X-Forwarded-For` header
    //   will only be sent on the first client request.

    "x-forward": false,

    // *Optional key*
    // If this property is present - balancing will start from the backend,
    // which `external` value is matching server address.
    // (Useful when listening on multiple interfaces)
    "external": "[1.2.3.4]:443"
  }],

  // SNI context loading
  "sni": {
    "enabled": false,
    "port": 9000,
    "host": "127.0.0.1",

    // %s will be replaced with actual servername
    "url": "/bud/sni/%s"
  },

  // OCSP Stapling response loading
  "stapling": {
    "enabled": false,
    "port": 9000,
    "host": "127.0.0.1",

    // %s will be replaced with actual servername
    "url": "/bud/stapling/%s"
  },

  // Secure contexts (i.e. Server Name Indication support)
  "contexts": [{
    // Servername to match against
    "servername": "blog.indutny.com",

    // **Optional** balance algorithm, could not be `sni`
    "balance": "roundrobin",

    // Path to TLS certificate
    // Could be an array
    "cert": "keys/cert.pem",

    // Path to TLS private key
    // Could be an array
    "key": "keys/key.pem",

    // **Optional** Passphrase for the private key
    // Could be an array
    "passphrase": null,

    // Cipherlist to use (overrides fronten

Bud

Install / Use

README

Bud