Add new rc: machine_id to generate /etc/machine-id

This new default-enabled rc will generate a /etc/machine-id file if it
does not exist, and pre-fill it with a newly generated UUID of version 4
[2].

The file is generated in /var/db/machine-id and symlinked to
/etc/machine-id to allow for read-only root partitions.

This file is amongst other things used by libraries like GLib.

Bump FreeBSD version 1400076 to be able to easily add support for older
version of FreeBSD via a package.

Bump FreeBSD version 1301511 to be able to easily add support for older
version of FreeBSD via a package.

[1] Linux machine-id(5): https://www.man7.org/linux/man-pages/man5/machine-id.5.html
[2] f176fe8e7f638e585afcd2f4dd52a522c4648f63

Approved by:		bapt
MFC after:		1 week
Differential Revision:	https://reviews.freebsd.org/D37722

(cherry picked from commit 62a149bf621947fb7475c64b1ff04fe19fe16b29)

5 files changed, 41 insertions, 1 deletions

diff --git a/etc/Makefile b/etc/Makefile
index 104e40b6e345..49a7a12a41b5 100644
--- a/etc/Makefile
+++ b/etc/Makefile
@@ -58,6 +58,8 @@ distribution:
 	${_+_}cd ${SRCTOP}/usr.sbin/rmt; ${MAKE} etc-rmt
 	${INSTALL_SYMLINK} -T "package=runtime" ../var/run/os-release \
 		${DESTDIR}/etc/os-release
+	${INSTALL_SYMLINK} -T "package=runtime" ../var/db/machine-id \
+		${DESTDIR}/etc/machine-id
 .if ${MK_UNBOUND} != "no"
 	if [ ! -e ${DESTDIR}/etc/unbound ]; then \
 		${INSTALL_SYMLINK} -T "package=unbound" \
diff --git a/libexec/rc/rc.conf b/libexec/rc/rc.conf
index 82796ba0ec48..e4f1ebe39de3 100644
--- a/libexec/rc/rc.conf
+++ b/libexec/rc/rc.conf
@@ -700,6 +700,9 @@ harvest_mask="511"	# Entropy device harvests all but the very invasive sources.
 osrelease_enable="YES"	# Update /var/run/os-release on boot (or NO).
 osrelease_file="/var/run/os-release" # File to update for os-release.
 osrelease_perms="444"	# Default permission for os-release file.
+machine_id_enable="YES"	# Create /var/db/machine-id on boot if missing (or NO).
+machine_id_file="/var/db/machine-id"	# File to update for machine-id.
+machine_id_perms="444"	# Default permissions for machine-id file.
 dmesg_enable="YES"	# Save dmesg(8) to /var/run/dmesg.boot
 watchdogd_enable="NO"	# Start the software watchdog daemon
 watchdogd_flags=""	# Flags to watchdogd (if enabled)
diff --git a/libexec/rc/rc.d/Makefile b/libexec/rc/rc.d/Makefile
index 0aa6b01448a5..0e7a04a5df1b 100644
--- a/libexec/rc/rc.d/Makefile
+++ b/libexec/rc/rc.d/Makefile
@@ -53,6 +53,7 @@ CONFS=	DAEMON \
 	local \
 	localpkg \
 	lockd \
+	machine_id \
 	mixer \
 	motd \
 	mountcritlocal \
diff --git a/libexec/rc/rc.d/machine_id b/libexec/rc/rc.d/machine_id
new file mode 100644
index 000000000000..7cfd7b2d92f8
--- /dev/null
+++ b/libexec/rc/rc.d/machine_id
@@ -0,0 +1,34 @@
+#!/bin/sh
+#
+# $FreeBSD$
+#
+
+# PROVIDE: machine_id
+# REQUIRE: mountcritremote FILESYSTEMS
+# BEFORE:  LOGIN
+
+. /etc/rc.subr
+
+: ${machine_id_file:=/var/db/machine-id}
+: ${machine_id_perms:=444}
+name="machine_id"
+desc="Update ${machine_id_file}"
+rcvar="machine_id_enable"
+start_cmd="machine_id_start"
+stop_cmd=":"
+
+
+machine_id_start()
+{
+	if [ ! -f ${machine_id_file} ] ; then
+		startmsg -n "Creating ${machine_id_file} "
+		t=$(mktemp -t machine-id)
+		/bin/uuidgen -r -o $t
+		install -C -o root -g wheel -m ${machine_id_perms} "$t" "${machine_id_file}"
+		rm -f "$t"
+		startmsg 'done.'
+	fi
+}
+
+load_rc_config $name
+run_rc_command "$1"
diff --git a/sys/sys/param.h b/sys/sys/param.h
index 57cf5937d952..4d1f940af760 100644
--- a/sys/sys/param.h
+++ b/sys/sys/param.h
@@ -60,7 +60,7 @@
  *		in the range 5 to 9.
  */
 #undef __FreeBSD_version
-#define __FreeBSD_version 1301510	/* Master, propagated to newvers */
+#define __FreeBSD_version 1301511	/* Master, propagated to newvers */
 
 /*
  * __FreeBSD_kernel__ indicates that this system uses the kernel of FreeBSD,