1 files changed, 105 insertions, 0 deletions
diff --git a/scripts/pjl-ready-message.nse b/scripts/pjl-ready-message.nse
new file mode 100644
index 0000000..a77f60f
--- /dev/null
+++ b/scripts/pjl-ready-message.nse
@@ -0,0 +1,105 @@
+local nmap = require "nmap"
+local shortport = require "shortport"
+
+description = [[
+Retrieves or sets the ready message on printers that support the Printer
+Job Language. This includes most PostScript printers that listen on port
+9100. Without an argument, displays the current ready message. With the
+<code>pjl_ready_message</code> script argument, displays the old ready
+message and changes it to the message given.
+]]
+
+---
+-- @arg pjl_ready_message Ready message to display.
+-- @output
+-- 9100/tcp open  jetdirect
+-- |_ pjl-ready-message: "READY" changed to "p0wn3d pr1nt3r"
+-- @usage
+-- nmap --script=pjl-ready-message.nse \
+--   --script-args='pjl_ready_message="your message here"'
+
+author = "Aaron Leininger"
+
+license = "Same as Nmap--See https://nmap.org/book/man-legal.html"
+
+categories = {"intrusive"}
+
+portrule = shortport.port_or_service(9100, "jetdirect")
+
+local function parse_response(response)
+  local msg
+  local line
+
+  for line in response:gmatch(".-\n") do
+    msg = line:match("^DISPLAY=\"(.*)\"")
+    if msg then
+      return msg
+    end
+  end
+end
+
+action = function(host, port)
+
+  local status  --to be used to grab the existing status of the display screen before changing it.
+  local newstatus  --used to repoll the printer after setting the display to check that the probe worked.
+  local statusmsg  --stores the PJL command to get the printer's status
+  local response  --stores the response sent over the network from the printer by the PJL status command
+
+  statusmsg="@PJL INFO STATUS\r\n"
+
+  local rdymsg=""  --string containing text to send to the printer.
+  local rdymsgarg=""  --will contain the argument from the command line if one exists
+
+  local socket = nmap.new_socket()
+  socket:set_timeout(15000)
+  local try = nmap.new_try(function() socket:close() end)
+  try(socket:connect(host, port))
+  try(socket:send(statusmsg))  --this block gets the current display status
+  local data
+  response,data=socket:receive()
+  if not response then  --send an initial probe. If no response, send nothing further.
+    socket:close()
+    if nmap.verbosity() > 0 then
+      return "No response from printer: "..data
+    else
+      return nil
+    end
+  end
+
+  status = parse_response(data)
+  if not status then
+    if nmap.verbosity() > 0 then
+      return "Error reading printer response: "..data
+    else
+      return nil
+    end
+  end
+
+  rdymsgarg = nmap.registry.args.pjl_ready_message
+  if not rdymsgarg then
+    if status then
+      return "\""..status.."\""
+    else
+      return nil
+    end
+  end
+
+  rdymsg="@PJL RDYMSG DISPLAY = \""..rdymsgarg.."\"\r\n"
+  try(socket:send(rdymsg))  --actually set the display message here.
+
+  try(socket:send(statusmsg))  --this block gets the status again for comparison
+  response,data=socket:receive()
+  if not response then
+    socket:close()
+    return "\""..status.."\""
+  end
+  newstatus=parse_response(data)
+  if not newstatus then
+    socket:close()
+    return "\""..status.."\""
+  end
+
+  socket:close()
+
+  return "\""..status.."\" changed to \""..newstatus.."\""
+end