class Net::SSH::Proxy::Command

An implementation of a command proxy. To use it, instantiate it, then pass the instantiated object via the :proxy key to Net::SSH.start:

require 'net/ssh/proxy/command'

proxy = Net::SSH::Proxy::Command.new('ssh relay nc %h %p')
Net::SSH.start('host', 'user', :proxy => proxy) do |ssh|
  ...
end

Attributes

command_line[R]

The command line for the session

command_line_template[R]

The command line template

Public Class Methods

new(command_line_template) click to toggle source

Create a new socket factory that tunnels via a command executed with the user's shell, which is composed from the given command template. In the command template, `%h' will be substituted by the host name to connect and `%p' by the port.

# File lib/net/ssh/proxy/command.rb, line 29
def initialize(command_line_template)
  @command_line_template = command_line_template
  @command_line = nil
end

Public Instance Methods

open(host, port) click to toggle source

Return a new socket connected to the given host and port via the proxy that was requested when the socket factory was instantiated.

# File lib/net/ssh/proxy/command.rb, line 36
def open(host, port)
  command_line = @command_line_template.gsub(%r%(.)/) {
    case $1
    when 'h'
      host
    when 'p'
      port.to_s
    when '%'
      '%'
    else
      raise ArgumentError, "unknown key: #{$1}"
    end
  }
  begin
    io = IO.popen(command_line, "r+")
    if result = Net::SSH::Compat.io_select([io], nil, [io], 60)
      if result.last.any?
        raise "command failed"
      end
    else
      raise "command timed out"
    end
  rescue => e
    raise ConnectError, "#{e}: #{command_line}"
  end
  @command_line = command_line
  class << io
    def send(data, flag)
      write_nonblock(data)
    end

    def recv(size)
      read_nonblock(size)
    end
  end
  io
end