units: further lock down our long-running services

Let's make this an excercise in dogfooding: let's turn on more security
features for all our long-running services.

Specifically:

- Turn on RestrictRealtime=yes for all of them

- Turn on ProtectKernelTunables=yes and ProtectControlGroups=yes for most of
  them

- Turn on RestrictAddressFamilies= for all of them, but different sets of
  address families for each

Also, always order settings in the unit files, that the various sandboxing
features are close together.

Add a couple of missing, older settings for a numbre of unit files.

Note that this change turns off AF_INET/AF_INET6 from udevd, thus effectively
turning of networking from udev rule commands. Since this might break stuff
(that is already broken I'd argue) this is documented in NEWS.

1 files changed, 9 insertions, 4 deletions

diff --git a/units/systemd-journal-remote.service.in b/units/systemd-journal-remote.service.in
index fdf3da4b64..753dd6c158 100644
--- a/units/systemd-journal-remote.service.in
+++ b/units/systemd-journal-remote.service.in
@@ -11,15 +11,20 @@ Documentation=man:systemd-journal-remote(8) man:journal-remote.conf(5)
 Requires=systemd-journal-remote.socket
 
 [Service]
-ExecStart=@rootlibexecdir@/systemd-journal-remote \
-          --listen-https=-3 \
-          --output=/var/log/journal/remote/
+ExecStart=@rootlibexecdir@/systemd-journal-remote --listen-https=-3 --output=/var/log/journal/remote/
 User=systemd-journal-remote
 Group=systemd-journal-remote
+WatchdogSec=3min
 PrivateTmp=yes
 PrivateDevices=yes
 PrivateNetwork=yes
-WatchdogSec=3min
+ProtectSystem=full
+ProtectHome=yes
+ProtectControlGroups=yes
+ProtectKernelTunables=yes
+MemoryDenyWriteExecute=yes
+RestrictRealtime=yes
+RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6
 
 [Install]
 Also=systemd-journal-remote.socket