From c81ed9a7e417e15b3c3e0ac500af52841b3f8575 Mon Sep 17 00:00:00 2001 From: Eric Wong Date: Wed, 4 Nov 2009 08:10:48 +0000 Subject: worker: user/group switching for after_fork hooks This must be called in the after_fork hook because there may be Ruby modules that'll allow things such as CPU affinity and scheduling class/priority to be set on a per-worker basis. So we give the user the ability to change users at any time during the after_fork hook. --- lib/unicorn.rb | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'lib/unicorn.rb') diff --git a/lib/unicorn.rb b/lib/unicorn.rb index 94be9d2..396b8e3 100644 --- a/lib/unicorn.rb +++ b/lib/unicorn.rb @@ -3,6 +3,7 @@ require 'fcntl' require 'unicorn/socket_helper' autoload :Rack, 'rack' +autoload :Etc, 'etc' # Unicorn module containing all of the classes (include C extensions) for running # a Unicorn web server. It contains a minimalist HTTP server with just enough @@ -117,6 +118,31 @@ module Unicorn def ==(other_nr) self.nr == other_nr end + + # Changes the worker process to the specified +user+ and +group+ + # This is only intended to be called from within the worker + # process from the +after_fork+ hook. This should be called in + # the +after_fork+ hook after any priviledged functions need to be + # run (e.g. to set per-worker CPU affinity, niceness, etc) + # + # Any and all errors raised within this method will be propagated + # directly back to the caller (usually the +after_fork+ hook. + # These errors commonly include ArgumentError for specifying an + # invalid user/group and Errno::EPERM for insufficient priviledges + def user(user, group = nil) + # we do not protect the caller, checking Process.euid == 0 is + # insufficient because modern systems have fine-grained + # capabilities. Let the caller handle any and all errors. + uid = Etc.getpwnam(user).uid + gid = Etc.getgrnam(group).gid if group + tmp.chown(uid, gid) + if gid && Process.egid != gid + Process.initgroups(user, gid) + Process::GID.change_privilege(gid) + end + Process.euid != uid and Process::UID.change_privilege(uid) + end + end # Creates a working server on host:port (strange things happen if -- cgit v1.2.3-24-ge0c7