From 9ce43e55f8db84ac1111ad29f0c134814f805fed Mon Sep 17 00:00:00 2001
From: Joey Hess <joeyh@joeyh.name>
Date: Wed, 27 May 2015 21:11:36 -0400
Subject: [PATCH] Improve enter-machine scripts for nspawn containers to unset
 most environment variables.

---
 config-joey.hs                    |  4 ++--
 debian/changelog                  |  2 ++
 src/Propellor/Property/Systemd.hs | 20 ++++++++++++--------
 3 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/config-joey.hs b/config-joey.hs
index 013be11..e01af47 100644
--- a/config-joey.hs
+++ b/config-joey.hs
@@ -134,10 +134,10 @@ orca = standardSystem "orca.kitenet.net" Unstable "amd64"
 	! Docker.docked (GitAnnexBuilder.standardAutoBuilderContainer dockerImage "amd64" 15 "2h")
 	! Docker.docked (GitAnnexBuilder.standardAutoBuilderContainer dockerImage "i386" 45 "2h")
 	! Docker.docked (GitAnnexBuilder.androidAutoBuilderContainer dockerImage (Cron.Times "1 1 * * *") "3h")
+	! Docker.docked (GitAnnexBuilder.armelCompanionContainer dockerImage)
+	! Docker.docked (GitAnnexBuilder.armelAutoBuilderContainer dockerImage (Cron.Times "1 3 * * *") "5h")
 	& Docker.garbageCollected -- `period` Daily
 	& Systemd.nspawned (GitAnnexBuilder.standardAutoBuilderContainerNspawn "amd64" 15 "2h")
-	& Docker.docked (GitAnnexBuilder.armelCompanionContainer dockerImage)
-	& Docker.docked (GitAnnexBuilder.armelAutoBuilderContainer dockerImage (Cron.Times "1 3 * * *") "5h")
 	& Apt.buildDep ["git-annex"] `period` Daily
 
 -- This is not a complete description of kite, since it's a
diff --git a/debian/changelog b/debian/changelog
index 96a9f74..5d70582 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -7,6 +7,8 @@ propellor (2.5.0) UNRELEASED; urgency=medium
   * Export CommandParam, boolSystem, safeSystem and shellEscape from
     Propellor.Property.Cmd, so they are available for use in constricting
     your own Properties when using propellor as a library.
+  * Improve enter-machine scripts for nspawn containers to unset most
+    environment variables.
 
  -- Joey Hess <id@joeyh.name>  Thu, 07 May 2015 12:08:34 -0400
 
diff --git a/src/Propellor/Property/Systemd.hs b/src/Propellor/Property/Systemd.hs
index 78a9996..b19c08b 100644
--- a/src/Propellor/Property/Systemd.hs
+++ b/src/Propellor/Property/Systemd.hs
@@ -215,15 +215,19 @@ enterScript c@(Container name _ _) = setup <!> teardown
   where
 	setup = combineProperties ("generated " ++ enterScriptFile c)
 		[ scriptfile `File.hasContent`
-			[ "#!/bin/sh"
+			[ "#!/usr/bin/perl"
 			, "# Generated by propellor"
-			, "pid=\"$(machinectl show " ++ shellEscape name ++ " -p Leader | cut -d= -f2)\" || true"
-			, "if [ -n \"$pid\" ]; then"
-			, "\tnsenter -p -u -n -i -m -t \"$pid\" \"$@\""
-			, "else"
-			, "\techo container not running >&2"
-			, "\texit 1"
-			, "fi"
+			, "my $pid=`machinectl show " ++ shellEscape name ++ " -p Leader | cut -d= -f2`;"
+			, "chomp $pid;"
+			, "if (length $pid) {"
+			, "\tforeach my $var (keys %ENV) {"
+			, "\t\tdelete $var unless $var eq 'PATH' || $var eq 'TERM';"
+			, "\t}"
+			, "\texec('nsenter', '-p', '-u', '-n', '-i', '-m', '-t', $pid, @ARGV);"
+			, "} else {"
+			, "\tdie 'container not running';"
+			, "}"
+			, "exit(1);"
 			]
 		, scriptfile `File.mode` combineModes (readModes ++ executeModes)
 		]