runc: introduce oci-systemd-hook

To support running "OS containers" aka systemd as the entry point under runc,
we provide the oci-systemd-hook.

By adding this to the pre-start and stop hook points, coupled with the proper
config.json, you can start systemd controlled containers via runc.

Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>

recipes-containers/oci-systemd-hook/oci-systemd-hook/0001-configure-drop-selinux-support.patch

@@ -0,0 +1,25 @@
+From 12c263703a0b0ae92566de7e5440fce7b59cd9be Mon Sep 17 00:00:00 2001
+From: Bruce Ashfield <bruce.ashfield@windriver.com>
+Date: Tue, 8 Nov 2016 13:16:19 -0500
+Subject: [PATCH] configure: drop selinux support
+
+Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>
+---
+ configure.ac | 1 -
+ 1 file changed, 1 deletion(-)
+
+diff --git a/configure.ac b/configure.ac
+index c1275acb253d..eaba7fbb57e2 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -8,7 +8,6 @@ AC_USE_SYSTEM_EXTENSIONS
+ AC_SYS_LARGEFILE
+ 
+ PKG_CHECK_MODULES([YAJL], [yajl >= 2.0.0])
+-PKG_CHECK_MODULES([SELINUX], [libselinux >= 2.0.0])
+ PKG_CHECK_MODULES([LIBMOUNT], [mount >= 2.23.0])
+ 
+ AC_MSG_CHECKING([whether to disable argument checking])
+-- 
+2.4.0.53.g8440f74
+

recipes-containers/oci-systemd-hook/oci-systemd-hook/0001-selinux-drop-selinux-support.patch

@@ -0,0 +1,40 @@
+From 9b66394c712ec0d0fcb2052baa7f590621a53461 Mon Sep 17 00:00:00 2001
+From: Bruce Ashfield <bruce.ashfield@windriver.com>
+Date: Tue, 8 Nov 2016 13:15:46 -0500
+Subject: [PATCH] selinux: drop selinux support
+
+Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>
+---
+ src/systemdhook.c | 9 ---------
+ 1 file changed, 9 deletions(-)
+
+diff --git a/src/systemdhook.c b/src/systemdhook.c
+index 274e5b910699..b9e8f1be376a 100644
+--- a/src/systemdhook.c
++++ b/src/systemdhook.c
+@@ -14,7 +14,6 @@
+ #include <errno.h>
+ #include <inttypes.h>
+ #include <linux/limits.h>
+-#include <selinux/selinux.h>
+ #include <yajl/yajl_tree.h>
+ 
+ #include "config.h"
+@@ -538,14 +537,6 @@ static int prestart(const char *rootfs,
+ 			}
+ 		}
+ 
+-		if (strcmp("", mount_label)) {
+-			rc = setfilecon(journal_dir, (security_context_t)mount_label);
+-			if (rc < 0) {
+-				pr_perror("Failed to set journal dir selinux context");
+-				return -1;
+-			}
+-		}
+-
+ 		if (makepath(cont_journal_dir, 0755) == -1) {
+ 			if (errno != EEXIST) {
+ 				pr_perror("Failed to mkdir container journal dir: %s", cont_journal_dir);
+-- 
+2.4.0.53.g8440f74
+

recipes-containers/oci-systemd-hook/oci-systemd-hook_git.bb

@@ -0,0 +1,35 @@
+DESCRIPTION = "OCI systemd hook enables users to run systemd in docker and OCI"
+SECTION = "console/utils"
+LICENSE = "GPLv3"
+LIC_FILES_CHKSUM = "file://LICENSE;md5=d32239bcb673463ab874e80d47fae504"
+PRIORITY = "optional"
+
+DEPENDS = "yajl util-linux"
+
+SRCREV = "ca515c1f399bd0b16e94b7c34aa1ef20498beca6"
+SRC_URI = "git://github.com/projectatomic/oci-systemd-hook \
+           file://0001-selinux-drop-selinux-support.patch \
+           file://0001-configure-drop-selinux-support.patch \
+"
+
+PV = "0.0.1+git${SRCPV}"
+S = "${WORKDIR}/git"
+
+inherit autotools pkgconfig
+
+PACKAGECONFIG ??= ""
+PACKAGECONFIG[selinux] = ",,libselinux"
+
+EXTRA_OECONF += "--libexecdir=${libexecdir}/oci/hooks.d"
+
+# nothing to compile, we do it all in the install task
+do_compile[noexec] = "1"
+
+do_install() {
+    # Avoid building docs, and other artifacts by surgically calling the
+    # semi-internal target of "install-exec-am"
+    oe_runmake 'DESTDIR=${D}' install-exec-am
+}
+
+FILES_${PN} += "${libexecdir}/oci/hooks.d/"
+