Module: Sparoid

Extended by:
Sparoid
Included in:
Sparoid, Instance
Defined in:
lib/sparoid.rb,
lib/sparoid/cli.rb,
lib/sparoid/version.rb

Overview

Single Packet Authorisation client

Defined Under Namespace

Classes: CLI, Error, Instance, ResolvError

Constant Summary collapse

SPAROID_CACHE_PATH = 
ENV.fetch("SPAROID_CACHE_PATH", "/tmp/.sparoid_public_ip")
VERSION = 
"1.2.0"

Instance Method Summary collapse

Instance Method Details

#auth(key, hmac_key, host, port, open_for_ip: cached_public_ip) ⇒ Object

Send an authorization packet



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# File 'lib/sparoid.rb', line 15

def auth(key, hmac_key, host, port, open_for_ip: cached_public_ip)
  addrs = resolve_ip_addresses(host, port)
  ip = Resolv::IPv4.create(open_for_ip)
  msg = message(ip)
  data = prefix_hmac(hmac_key, encrypt(key, msg))
  sendmsg(addrs, data)

  # wait some time for the server to actually open the port
  # if we don't wait the next SYN package will be dropped
  # and it have to be redelivered, adding 1 second delay
  sleep 0.02

  addrs.map(&:ip_address) # return resolved IP(s)
end

#fdpass(ips, port, connect_timeout: 10) ⇒ Object

Connect to a TCP server and pass the FD to the parent



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# File 'lib/sparoid.rb', line 40

def fdpass(ips, port, connect_timeout: 10) # rubocop:disable Metrics/AbcSize, Metrics/MethodLength
  # try connect to all IPs
  sockets = ips.map do |ip|
    Socket.new(Socket::AF_INET, Socket::SOCK_STREAM).tap do |s|
      s.connect_nonblock(Socket.sockaddr_in(port, ip), exception: false)
    end
  end
  # wait for any socket to be connected
  until sockets.empty?
    _, writeable, errors = IO.select(nil, sockets, nil, connect_timeout) || break
    errors.each { |s| sockets.delete(s) }
    writeable.each do |s|
      idx = sockets.index(s)
      sockets.delete_at(idx) # don't retry this socket again
      ip = ips.delete_at(idx) # find the IP for the socket
      begin
        s.connect_nonblock(Socket.sockaddr_in(port, ip)) # check for errors
      rescue Errno::EISCONN
        # already connected, continue
      rescue SystemCallError
        next # skip connection errors, hopefully at least one succeeds
      end
      # pass the connected FD to the parent process over STDOUT
      Socket.for_fd(1).sendmsg "\0", 0, nil, Socket::AncillaryData.unix_rights(s)
      exit 0 # exit as fast as possible so that other sockets don't connect
    end
  end
  exit 1 # all connections failed
end

#keygen ⇒ Object

Generate new aes and hmac keys, print to stdout



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# File 'lib/sparoid.rb', line 31

def keygen
  cipher = OpenSSL::Cipher.new("aes-256-cbc")
  key = cipher.random_key.unpack1("H*")
  hmac_key = OpenSSL::Random.random_bytes(32).unpack1("H*")
  puts "key = #{key}"
  puts "hmac-key = #{hmac_key}"
end