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#
# Author:: Adam Jacob (<adam@chef.io>)
# Copyright:: Copyright 2009-2016, Chef Software Inc.
# License:: Apache License, Version 2.0
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
require "chef/mixin/shell_out"
require "chef/knife"
class Chef
class Knife
class Ssh < Knife
deps do
require "net/ssh"
require "net/ssh/multi"
require "readline"
require "chef/exceptions"
require "chef/search/query"
require "chef/util/path_helper"
require "mixlib/shellout"
end
include Chef::Mixin::ShellOut
attr_writer :password
banner "knife ssh QUERY COMMAND (options)"
option :concurrency,
:short => "-C NUM",
:long => "--concurrency NUM",
:description => "The number of concurrent connections",
:default => nil,
:proc => lambda { |o| o.to_i }
option :attribute,
:short => "-a ATTR",
:long => "--attribute ATTR",
:description => "The attribute to use for opening the connection - default depends on the context",
:proc => Proc.new { |key| Chef::Config[:knife][:ssh_attribute] = key.strip }
option :manual,
:short => "-m",
:long => "--manual-list",
:boolean => true,
:description => "QUERY is a space separated list of servers",
:default => false
option :ssh_user,
:short => "-x USERNAME",
:long => "--ssh-user USERNAME",
:description => "The ssh username"
option :ssh_password_ng,
:short => "-P [PASSWORD]",
:long => "--ssh-password [PASSWORD]",
:description => "The ssh password - will prompt if flag is specified but no password is given",
# default to a value that can not be a password (boolean)
# so we can effectively test if this parameter was specified
# without a value
:default => false
option :ssh_port,
:short => "-p PORT",
:long => "--ssh-port PORT",
:description => "The ssh port",
:proc => Proc.new { |key| Chef::Config[:knife][:ssh_port] = key.strip }
option :ssh_timeout,
:short => "-t SECONDS",
:long => "--ssh-timeout SECONDS",
:description => "The ssh connection timeout",
:proc => Proc.new { |key| Chef::Config[:knife][:ssh_timeout] = key.strip.to_i },
:default => 120
option :ssh_gateway,
:short => "-G GATEWAY",
:long => "--ssh-gateway GATEWAY",
:description => "The ssh gateway",
:proc => Proc.new { |key| Chef::Config[:knife][:ssh_gateway] = key.strip }
option :forward_agent,
:short => "-A",
:long => "--forward-agent",
:description => "Enable SSH agent forwarding",
:boolean => true
option :identity_file,
:long => "--identity-file IDENTITY_FILE",
:description => "The SSH identity file used for authentication. [DEPRECATED] Use --ssh-identity-file instead."
option :ssh_identity_file,
:short => "-i IDENTITY_FILE",
:long => "--ssh-identity-file IDENTITY_FILE",
:description => "The SSH identity file used for authentication"
option :host_key_verify,
:long => "--[no-]host-key-verify",
:description => "Verify host key, enabled by default.",
:boolean => true,
:default => true
option :on_error,
:short => "-e",
:long => "--exit-on-error",
:description => "Immediately exit if an error is encountered",
:boolean => true,
:proc => Proc.new { :raise }
option :tmux_split,
:long => "--tmux-split",
:description => "Split tmux window.",
:boolean => true,
:default => false
def session
config[:on_error] ||= :skip
ssh_error_handler = Proc.new do |server|
case config[:on_error]
when :skip
ui.warn "Failed to connect to #{server.host} -- #{$!.class.name}: #{$!.message}"
$!.backtrace.each { |l| Chef::Log.debug(l) }
when :raise
#Net::SSH::Multi magic to force exception to be re-raised.
throw :go, :raise
end
end
@session ||= Net::SSH::Multi.start(:concurrent_connections => config[:concurrency], :on_error => ssh_error_handler)
end
def configure_gateway
config[:ssh_gateway] ||= Chef::Config[:knife][:ssh_gateway]
if config[:ssh_gateway]
gw_host, gw_user = config[:ssh_gateway].split("@").reverse
gw_host, gw_port = gw_host.split(":")
gw_opts = session_options(gw_host, gw_port, gw_user)
user = gw_opts.delete(:user)
begin
# Try to connect with a key.
session.via(gw_host, user, gw_opts)
rescue Net::SSH::AuthenticationFailed
prompt = "Enter the password for #{user}@#{gw_host}: "
gw_opts[:password] = prompt_for_password(prompt)
# Try again with a password.
session.via(gw_host, user, gw_opts)
end
end
end
def configure_session
list = config[:manual] ? @name_args[0].split(" ") : search_nodes
if list.length == 0
if @search_count == 0
ui.fatal("No nodes returned from search")
else
ui.fatal("#{@search_count} #{@search_count > 1 ? "nodes" : "node"} found, " +
"but does not have the required attribute to establish the connection. " +
"Try setting another attribute to open the connection using --attribute.")
end
exit 10
end
session_from_list(list)
end
def get_ssh_attribute(node)
# Order of precedence for ssh target
# 1) command line attribute
# 2) configuration file
# 3) cloud attribute
# 4) fqdn
if node["config"]
Chef::Log.debug("Using node attribute '#{config[:attribute]}' as the ssh target: #{node["config"]}")
node["config"]
elsif Chef::Config[:knife][:ssh_attribute]
Chef::Log.debug("Using node attribute #{Chef::Config[:knife][:ssh_attribute]}: #{node["knife_config"]}")
node["knife_config"]
elsif node["cloud"] &&
node["cloud"]["public_hostname"] &&
!node["cloud"]["public_hostname"].empty?
Chef::Log.debug("Using node attribute 'cloud[:public_hostname]' automatically as the ssh target: #{node["cloud"]["public_hostname"]}")
node["cloud"]["public_hostname"]
else
# falling back to default of fqdn
Chef::Log.debug("Using node attribute 'fqdn' as the ssh target: #{node["fqdn"]}")
node["fqdn"]
end
end
def search_nodes
list = Array.new
query = Chef::Search::Query.new
required_attributes = { fqdn: ["fqdn"], cloud: ["cloud"] }
separator = ui.presenter.attribute_field_separator
# if we've set an attribute to use on the command line
if config[:attribute]
required_attributes[:config] = config[:attribute].split(separator)
end
# if we've configured an attribute in our config
if Chef::Config[:knife][:ssh_attribute]
required_attributes[:knife_config] = Chef::Config[:knife][:ssh_attribute].split(separator)
end
@search_count = 0
query.search(:node, @name_args[0], filter_result: required_attributes) do |item|
@search_count += 1
# we should skip the loop to next iteration if the item
# returned by the search is nil
next if item.nil?
# next if we couldn't find the specified attribute in the
# returned node object
host = get_ssh_attribute(item)
next if host.nil?
ssh_port = item[:cloud].nil? ? nil : item[:cloud][:public_ssh_port]
srv = [host, ssh_port]
list.push(srv)
end
list
end
# Net::SSH session options hash for global options. These should be
# options that will apply to the gateway connection in addition to the
# main one.
#
# @since 12.5.0
# @param host [String] Hostname for this session.
# @param port [String] SSH port for this session.
# @param user [String] Optional username for this session.
# @return [Hash<Symbol, Object>]
def session_options(host, port, user = nil)
ssh_config = Net::SSH.configuration_for(host, true)
{}.tap do |opts|
# Chef::Config[:knife][:ssh_user] is parsed in #configure_user and written to config[:ssh_user]
opts[:user] = user || config[:ssh_user] || ssh_config[:user]
if config[:ssh_identity_file]
opts[:keys] = File.expand_path(config[:ssh_identity_file])
opts[:keys_only] = true
elsif config[:ssh_password]
opts[:password] = config[:ssh_password]
end
# Don't set the keys to nil if we don't have them.
forward_agent = config[:forward_agent] || ssh_config[:forward_agent]
opts[:forward_agent] = forward_agent unless forward_agent.nil?
port ||= ssh_config[:port]
opts[:port] = port unless port.nil?
opts[:logger] = Chef::Log.logger if Chef::Log.level == :debug
if !config[:host_key_verify]
opts[:paranoid] = false
opts[:user_known_hosts_file] = "/dev/null"
end
end
end
def session_from_list(list)
list.each do |item|
host, ssh_port = item
Chef::Log.debug("Adding #{host}")
session_opts = session_options(host, ssh_port)
# Handle port overrides for the main connection.
session_opts[:port] = Chef::Config[:knife][:ssh_port] if Chef::Config[:knife][:ssh_port]
session_opts[:port] = config[:ssh_port] if config[:ssh_port]
# Handle connection timeout
session_opts[:timeout] = Chef::Config[:knife][:ssh_timeout] if Chef::Config[:knife][:ssh_timeout]
session_opts[:timeout] = config[:ssh_timeout] if config[:ssh_timeout]
# Create the hostspec.
hostspec = session_opts[:user] ? "#{session_opts.delete(:user)}@#{host}" : host
# Connect a new session on the multi.
session.use(hostspec, session_opts)
@longest = host.length if host.length > @longest
end
session
end
def fixup_sudo(command)
command.sub(/^sudo/, 'sudo -p \'knife sudo password: \'')
end
def print_data(host, data)
@buffers ||= {}
if leftover = @buffers[host]
@buffers[host] = nil
print_data(host, leftover + data)
else
if newline_index = data.index("\n")
line = data.slice!(0...newline_index)
data.slice!(0)
print_line(host, line)
print_data(host, data)
else
@buffers[host] = data
end
end
end
def print_line(host, data)
padding = @longest - host.length
str = ui.color(host, :cyan) + (" " * (padding + 1)) + data
ui.msg(str)
end
def ssh_command(command, subsession = nil)
exit_status = 0
subsession ||= session
command = fixup_sudo(command)
command.force_encoding("binary") if command.respond_to?(:force_encoding)
subsession.open_channel do |chan|
chan.request_pty
chan.exec command do |ch, success|
raise ArgumentError, "Cannot execute #{command}" unless success
ch.on_data do |ichannel, data|
print_data(ichannel[:host], data)
if data =~ /^knife sudo password: /
print_data(ichannel[:host], "\n")
ichannel.send_data("#{get_password}\n")
end
end
ch.on_request "exit-status" do |ichannel, data|
exit_status = [exit_status, data.read_long].max
end
end
end
session.loop
exit_status
end
def get_password
@password ||= prompt_for_password
end
def prompt_for_password(prompt = "Enter your password: ")
ui.ask(prompt) { |q| q.echo = false }
end
# Present the prompt and read a single line from the console. It also
# detects ^D and returns "exit" in that case. Adds the input to the
# history, unless the input is empty. Loops repeatedly until a non-empty
# line is input.
def read_line
loop do
command = reader.readline("#{ui.color('knife-ssh>', :bold)} ", true)
if command.nil?
command = "exit"
puts(command)
else
command.strip!
end
unless command.empty?
return command
end
end
end
def reader
Readline
end
def interactive
puts "Connected to #{ui.list(session.servers_for.collect { |s| ui.color(s.host, :cyan) }, :inline, " and ")}"
puts
puts "To run a command on a list of servers, do:"
puts " on SERVER1 SERVER2 SERVER3; COMMAND"
puts " Example: on latte foamy; echo foobar"
puts
puts "To exit interactive mode, use 'quit!'"
puts
loop do
command = read_line
case command
when "quit!"
puts "Bye!"
break
when /^on (.+?); (.+)$/
raw_list = $1.split(" ")
server_list = Array.new
session.servers.each do |session_server|
server_list << session_server if raw_list.include?(session_server.host)
end
command = $2
ssh_command(command, session.on(*server_list))
else
ssh_command(command)
end
end
end
def screen
tf = Tempfile.new("knife-ssh-screen")
Chef::Util::PathHelper.home(".screenrc") do |screenrc_path|
if File.exist? screenrc_path
tf.puts("source #{screenrc_path}")
end
end
tf.puts("caption always '%-Lw%{= BW}%50>%n%f* %t%{-}%+Lw%<'")
tf.puts("hardstatus alwayslastline 'knife ssh #{@name_args[0]}'")
window = 0
session.servers_for.each do |server|
tf.print("screen -t \"#{server.host}\" #{window} ssh ")
tf.print("-i #{config[:ssh_identity_file]} ") if config[:ssh_identity_file]
server.user ? tf.puts("#{server.user}@#{server.host}") : tf.puts(server.host)
window += 1
end
tf.close
exec("screen -c #{tf.path}")
end
def tmux
ssh_dest = lambda do |server|
identity = "-i #{config[:ssh_identity_file]} " if config[:ssh_identity_file]
prefix = server.user ? "#{server.user}@" : ""
"'ssh #{identity}#{prefix}#{server.host}'"
end
new_window_cmds = lambda do
if session.servers_for.size > 1
[""] + session.servers_for[1..-1].map do |server|
if config[:tmux_split]
"split-window #{ssh_dest.call(server)}; tmux select-layout tiled"
else
"new-window -a -n '#{server.host}' #{ssh_dest.call(server)}"
end
end
else
[]
end.join(" \\; ")
end
tmux_name = "'knife ssh #{@name_args[0].tr(':', '=')}'"
begin
server = session.servers_for.first
cmd = ["tmux new-session -d -s #{tmux_name}",
"-n '#{server.host}'", ssh_dest.call(server),
new_window_cmds.call].join(" ")
shell_out!(cmd)
exec("tmux attach-session -t #{tmux_name}")
rescue Chef::Exceptions::Exec
end
end
def macterm
begin
require "appscript"
rescue LoadError
STDERR.puts "You need the rb-appscript gem to use knife ssh macterm. `(sudo) gem install rb-appscript` to install"
raise
end
Appscript.app("/Applications/Utilities/Terminal.app").windows.first.activate
Appscript.app("System Events").application_processes["Terminal.app"].keystroke("n", :using => :command_down)
term = Appscript.app("Terminal")
window = term.windows.first.get
(session.servers_for.size - 1).times do |i|
window.activate
Appscript.app("System Events").application_processes["Terminal.app"].keystroke("t", :using => :command_down)
end
session.servers_for.each_with_index do |server, tab_number|
cmd = "unset PROMPT_COMMAND; echo -e \"\\033]0;#{server.host}\\007\"; ssh #{server.user ? "#{server.user}@#{server.host}" : server.host}"
Appscript.app("Terminal").do_script(cmd, :in => window.tabs[tab_number + 1].get)
end
end
def cssh
cssh_cmd = nil
%w{csshX cssh}.each do |cmd|
begin
# Unix and Mac only
cssh_cmd = shell_out!("which #{cmd}").stdout.strip
break
rescue Mixlib::ShellOut::ShellCommandFailed
end
end
raise Chef::Exceptions::Exec, "no command found for cssh" unless cssh_cmd
# pass in the consolidated identity file option to cssh(X)
if config[:ssh_identity_file]
cssh_cmd << " --ssh_args '-i #{File.expand_path(config[:ssh_identity_file])}'"
end
session.servers_for.each do |server|
cssh_cmd << " #{server.user ? "#{server.user}@#{server.host}" : server.host}"
end
Chef::Log.debug("Starting cssh session with command: #{cssh_cmd}")
exec(cssh_cmd)
end
def get_stripped_unfrozen_value(value)
return nil if value.nil?
value.strip
end
def configure_user
config[:ssh_user] = get_stripped_unfrozen_value(config[:ssh_user] ||
Chef::Config[:knife][:ssh_user])
end
# This is a bit overly complicated because of the way we want knife ssh to work with -P causing a password prompt for
# the user, but we have to be conscious that this code gets included in knife bootstrap and knife * server create as
# well. We want to change the semantics so that the default is false and 'nil' means -P without an argument on the
# command line. But the other utilities expect nil to be the default and we can't prompt in that case. So we effectively
# use ssh_password_ng to determine if we're coming from knife ssh or from the other utilities. The other utilties can
# also be patched to use ssh_password_ng easily as long they follow the convention that the default is false.
def configure_password
if config.has_key?(:ssh_password_ng) && config[:ssh_password_ng].nil?
# If the parameter is called on the command line with no value
# it will set :ssh_password_ng = nil
# This is where we want to trigger a prompt for password
config[:ssh_password] = get_password
else
# if ssh_password_ng is false then it has not been set at all, and we may be in knife ec2 and still
# using an old config[:ssh_password]. this is backwards compatibility. all knife cloud plugins should
# be updated to use ssh_password_ng with a default of false and ssh_password should be retired, (but
# we'll still need to use the ssh_password out of knife.rb if we find that).
ssh_password = config.has_key?(:ssh_password_ng) ? config[:ssh_password_ng] : config[:ssh_password]
# Otherwise, the password has either been specified on the command line,
# in knife.rb, or key based auth will be attempted
config[:ssh_password] = get_stripped_unfrozen_value(ssh_password ||
Chef::Config[:knife][:ssh_password])
end
end
def configure_ssh_identity_file
# config[:identity_file] is DEPRECATED in favor of :ssh_identity_file
config[:ssh_identity_file] = get_stripped_unfrozen_value(config[:ssh_identity_file] || config[:identity_file] || Chef::Config[:knife][:ssh_identity_file])
end
def run
@longest = 0
configure_user
configure_password
@password = config[:ssh_password] if config[:ssh_password]
configure_ssh_identity_file
configure_gateway
configure_session
exit_status =
case @name_args[1]
when "interactive"
interactive
when "screen"
screen
when "tmux"
tmux
when "macterm"
macterm
when "cssh"
cssh
when "csshx"
Chef::Log.warn("knife ssh csshx will be deprecated in a future release")
Chef::Log.warn("please use knife ssh cssh instead")
cssh
else
ssh_command(@name_args[1..-1].join(" "))
end
session.close
if exit_status != 0
exit exit_status
else
exit_status
end
end
private :search_nodes
end
end
end