Add systemd unit file

Refs: #4594
Change-Id: I415bafa14902e9d43be4891f66349192e12b9166
diff --git a/systemd/nlsr.service.in b/systemd/nlsr.service.in
new file mode 100644
index 0000000..9cce740
--- /dev/null
+++ b/systemd/nlsr.service.in
@@ -0,0 +1,57 @@
+# Copyright (c) 2014-2019, The University of Memphis,
+#                          Regents of the University of California,
+#                          Arizona Board of Regents.
+#
+# This file is part of NLSR (Named-data Link State Routing).
+# See AUTHORS.md for complete list of NLSR authors and contributors.
+#
+# NLSR is free software: you can redistribute it and/or modify it under the terms
+# of the GNU General Public License as published by the Free Software Foundation,
+# either version 3 of the License, or (at your option) any later version.
+#
+# NLSR is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+# without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+# PURPOSE.  See the GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along with
+# NLSR, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+#
+# Author: Eric Newberry <enewberry@email.arizona.edu>
+# Author: Davide Pesavento <davidepesa@gmail.com>
+
+[Unit]
+Description=NDN Link State Routing Daemon
+Documentation=man:nlsr(1)
+BindsTo=nfd.service
+After=nfd.service
+
+[Service]
+Environment=HOME=%S/ndn/nlsr
+ExecStart=@BINDIR@/nlsr -f @SYSCONFDIR@/ndn/nlsr.conf
+Restart=on-failure
+RestartPreventExitStatus=2
+User=nlsr
+
+LockPersonality=yes
+MemoryDenyWriteExecute=yes
+NoNewPrivileges=yes
+PrivateDevices=yes
+PrivateTmp=yes
+PrivateUsers=yes
+ProtectControlGroups=yes
+ProtectHome=yes
+ProtectKernelModules=yes
+ProtectKernelTunables=yes
+ProtectSystem=strict
+RestrictAddressFamilies=AF_UNIX AF_INET AF_INET6
+RestrictNamespaces=yes
+RestrictRealtime=yes
+# "nlsr" is the state-dir, "ndn/nlsr" is the HOME
+StateDirectory=nlsr ndn/nlsr
+SystemCallArchitectures=native
+SystemCallErrorNumber=EPERM
+SystemCallFilter=~@clock @cpu-emulation @debug @module @mount @obsolete @privileged @raw-io @reboot @setuid @swap
+
+[Install]
+WantedBy=multi-user.target
+WantedBy=nfd.service