Merge branch 'key-validations' into 'master'

Defense in depth for authorized_keys lines

Validate the key_id and public_key inputs when rendering the actual
'line' we append to authorized_keys. Although these inputs are either
trusted (key_id) or validated earlier (public_key) it does not hurt to
take a little extra care that we do not write unintended data to the
authorized_keys file.

See merge request !82

1 files changed, 5 insertions, 0 deletions

diff --git a/lib/gitlab_keys.rb b/lib/gitlab_keys.rb
index dc654fd..d4c4102 100644
--- a/lib/gitlab_keys.rb
+++ b/lib/gitlab_keys.rb
@@ -4,13 +4,18 @@ require_relative 'gitlab_config'
 require_relative 'gitlab_logger'
 
 class GitlabKeys
+  class KeyError < StandardError ; end
+
   attr_accessor :auth_file, :key
 
   def self.command(key_id)
+    raise KeyError.new("Invalid key_id: #{key_id.inspect}") unless /\A[a-z0-9-]+\z/ =~ key_id
     "#{ROOT_PATH}/bin/gitlab-shell #{key_id}"
   end
 
   def self.key_line(key_id, public_key)
+    public_key.chomp!
+    raise KeyError.new("Invalid public_key: #{public_key.inspect}") if public_key.include?("\n")
     "command=\"#{command(key_id)}\",no-port-forwarding,no-X11-forwarding,no-agent-forwarding,no-pty #{public_key}"
   end