Update systemd.service

conf/systemd.service

@@ -16,24 +16,35 @@ StandardError=syslog
 SyslogIdentifier=__APP__
 Restart=always
 
-; Some security directives.
-; Use private /tmp and /var/tmp folders inside a new file system namespace,
-; which are discarded after the process stops.
-PrivateTmp=true
-; Mount /usr, /boot, and /etc as read-only for processes invoked by this service.
+# Sandboxing options to harden security
+# Depending on specificities of your service/app, you may need to tweak these 
+# .. but this should be a good baseline
+# Details for these options: https://www.freedesktop.org/software/systemd/man/systemd.exec.html
+NoNewPrivileges=yes
+PrivateTmp=yes
+PrivateDevices=yes
+RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6
+RestrictNamespaces=yes
+RestrictRealtime=yes
+DevicePolicy=closed
 ProtectSystem=full
-; Sets up a new /dev mount for the process and only adds API pseudo devices
-; like /dev/null, /dev/zero or /dev/random but not physical devices. Disabled
-; by default because it may not work on devices like the Raspberry Pi.
-PrivateDevices=false
-; Ensures that the service process and all its children can never gain new
-; privileges through execve().
-NoNewPrivileges=true
-; This makes /home, /root, and /run/user inaccessible and empty for processes invoked
-; by this unit. Make sure that you do not depend on data inside these folders.
-ProtectHome=false
-; Drops the sys admin capability from the daemon.
-CapabilityBoundingSet=~CAP_SYS_ADMIN
+ProtectControlGroups=yes
+ProtectKernelModules=yes
+ProtectKernelTunables=yes
+LockPersonality=yes
+SystemCallFilter=~@clock @debug @module @mount @obsolete @reboot @setuid @swap
+
+# Denying access to capabilities that should not be relevant for webapps
+# Doc: https://man7.org/linux/man-pages/man7/capabilities.7.html
+CapabilityBoundingSet=~CAP_RAWIO CAP_MKNOD
+CapabilityBoundingSet=~CAP_AUDIT_CONTROL CAP_AUDIT_READ CAP_AUDIT_WRITE
+CapabilityBoundingSet=~CAP_SYS_BOOT CAP_SYS_TIME CAP_SYS_MODULE CAP_SYS_PACCT
+CapabilityBoundingSet=~CAP_LEASE CAP_LINUX_IMMUTABLE CAP_IPC_LOCK
+CapabilityBoundingSet=~CAP_BLOCK_SUSPEND CAP_WAKE_ALARM
+CapabilityBoundingSet=~CAP_SYS_TTY_CONFIG
+CapabilityBoundingSet=~CAP_MAC_ADMIN CAP_MAC_OVERRIDE
+CapabilityBoundingSet=~CAP_NET_ADMIN CAP_NET_BROADCAST CAP_NET_RAW
+CapabilityBoundingSet=~CAP_SYS_ADMIN CAP_SYS_PTRACE CAP_SYSLOG 
 
 [Install]
 WantedBy=multi-user.target