gitlab-org--gitlab-foss/lib/gitlab/authorized_keys.rb

167 lines
4.1 KiB
Ruby

# frozen_string_literal: true
module Gitlab
class AuthorizedKeys
KeyError = Class.new(StandardError)
attr_reader :logger
# Initializes the class
#
# @param [Gitlab::Logger] logger
def initialize(logger = Gitlab::AppLogger)
@logger = logger
end
# Checks if the file is accessible or not
#
# @return [Boolean]
def accessible?
open_authorized_keys_file('r') { true }
rescue Errno::ENOENT, Errno::EACCES
false
end
# Creates the authorized_keys file if it doesn't exist
#
# @return [Boolean]
def create
open_authorized_keys_file(File::CREAT) { true }
rescue Errno::EACCES
false
end
# Add id and its key to the authorized_keys file
#
# @param [String] id identifier of key prefixed by `key-`
# @param [String] key public key to be added
# @return [Boolean]
def add_key(id, key)
lock do
public_key = strip(key)
logger.info("Adding key (#{id}): #{public_key}")
open_authorized_keys_file('a') { |file| file.puts(key_line(id, public_key)) }
end
true
end
# Atomically add all the keys to the authorized_keys file
#
# @param [Array<::Key>] keys list of Key objects to be added
# @return [Boolean]
def batch_add_keys(keys)
lock(300) do # Allow 300 seconds (5 minutes) for batch_add_keys
open_authorized_keys_file('a') do |file|
keys.each do |key|
public_key = strip(key.key)
logger.info("Adding key (#{key.shell_id}): #{public_key}")
file.puts(key_line(key.shell_id, public_key))
end
end
end
true
rescue Gitlab::AuthorizedKeys::KeyError
false
end
# Remove key by ID from the authorized_keys file
#
# @param [String] id identifier of the key to be removed prefixed by `key-`
# @return [Boolean]
def remove_key(id)
lock do
logger.info("Removing key (#{id})")
open_authorized_keys_file('r+') do |f|
while line = f.gets
next unless line.start_with?("command=\"#{command(id)}\"")
f.seek(-line.length, IO::SEEK_CUR)
# Overwrite the line with #'s. Because the 'line' variable contains
# a terminating '\n', we write line.length - 1 '#' characters.
f.write('#' * (line.length - 1))
end
end
end
true
rescue Errno::ENOENT
false
end
# Clear the authorized_keys file
#
# @return [Boolean]
def clear
open_authorized_keys_file('w') { |file| file.puts '# Managed by gitlab-rails' }
true
end
# Read the authorized_keys file and return IDs of each key
#
# @return [Array<Integer>]
def list_key_ids
logger.info('Listing all key IDs')
[].tap do |a|
open_authorized_keys_file('r') do |f|
f.each_line do |line|
key_id = line.match(/key-(\d+)/)
next unless key_id
a << key_id[1].chomp.to_i
end
end
end
rescue Errno::ENOENT
[]
end
def file
@file ||= Gitlab.config.gitlab_shell.authorized_keys_file
end
private
def lock(timeout = 10)
File.open("#{file}.lock", "w+") do |f|
f.flock File::LOCK_EX
Timeout.timeout(timeout) { yield }
ensure
f.flock File::LOCK_UN
end
end
def open_authorized_keys_file(mode)
File.open(file, mode, 0o600) do |file|
file.chmod(0o600)
yield file
end
end
def key_line(id, key)
key = key.chomp
if key.include?("\n") || key.include?("\t")
raise KeyError, "Invalid public_key: #{key.inspect}"
end
%Q(command="#{command(id)}",no-port-forwarding,no-X11-forwarding,no-agent-forwarding,no-pty #{strip(key)})
end
def command(id)
unless /\A[a-z0-9-]+\z/ =~ id
raise KeyError, "Invalid ID: #{id.inspect}"
end
"#{File.join(Gitlab.config.gitlab_shell.path, 'bin', 'gitlab-shell')} #{id}"
end
def strip(key)
key.split(/ +/)[0, 2].join(' ')
end
end
end