VPPSniffer

Overview

A simple Linux 3.X kernel modules for debugging and sniffing parallel port (LPT)applications without real physical port

It also works with VirtualBox

Tested in Linux Debian 8.0 (Jessie) with Linux kernel 3.16.0

Contents

• parportvirt: virtual parallel port sources kernel module
• parportsnif: parallel port sniffer kernel module for linux 3.X
• install_port: simple "make and install" script
• set_vbox_settings: simple VirualBox configuring script

Installation

Simple

~$ ./install_port

Manual

# insert and remove standard modules (if yuo don't have physical LPT)
~$ sudo modprobe parport_pc
~$ sudo modprobe ppdev
~$ sudo rmmod lp

# build kernel modules
~$ make
# insert modules
sudo make insert

#change privileges for users
~$ sudo chmod 666 /dev/parportsnif0 
~$ sudo chmod 666 /dev/parport0

Using

You can test correct installation and runnig modules by this command:

~$ ls /dev/parport*

Correct responce must be like this:

/dev/parport0  /dev/parportsnif0

Device /dev/parport0 is parallel port (virtual or real if exist) Device /dev/parportsnif0 is fake parallel port for sniffering All information from sniffer logged to /proc/parportlog file

Testing

Start write sniffer log file to dump.ols

~$ cat /proc/parportlog > dump.ols

Run test program

~$ ./sniftest/sniftest

Press Ctrl+C to break logging and open dump file dump.ols

;Rate: 1000000
;Channels: 32
0000000055@100099
00000000AA@200170
0000000055@300247
00000000AA@400317
0000000000@500387
# [1433923145.442004659] 0 CLOSE

You can open dump.ols with Open Logic Sniffer

Data Format

Output sniffer data provided in Open Logic Sniffer format: Header:

;Rate: 1000000
;Channels: 32

Channels 0-7: Data register D0-D7 (address 0x378 for LPT1) Channels 16-23: Status register S0-S7 (address 0x37a for LPT1)

Data:

<HEX_DATA>@<TIME_STAMP>

<HEX_DATA> - 10-bit hex value of portdata. Digits 1-0 match to channels 7-0, digits 5-4 match to channels 23-16 (in binary format, MSB first)

<TIME_STAMP> - 6-digits decimal time stamp in microseconds (from port opening)

Footer:

# [1433923145.442004659] 0 CLOSE

Don't use by Open Logic Sniffer

Note: For dump from VirtualBox you must manually write header to dump file!

VirtualBox configuration

Configure LPT1 port (0x378 address) for Windows Virtual Machine in VirtualBox

Manual

# add /dev/parport0 as LPT1 (address 0x378, IRQ 7)
~$ VBoxManage modifyvm --lptmode1 /dev/parport0
~$ VBoxManage modifyvm --lpt1 0x378 7
# configure port
~$ VBoxManage setextradata <VM_NAME> "VBoxInternal/Devices/parallel/0/LUN#0/Config/DevicePath" /dev/parportsnif0
~$ VBoxManage setextradata <VM_NAME> "VBoxInternal/Devices/parallel/0/LUN#0/Driver" HostParallel
~$ VBoxManage setextradata <VM_NAME> "VBoxInternal/Devices/parallel/0/Config/IOBase" 0x378
~$ VBoxManage setextradata <VM_NAME> "VBoxInternal/Devices/parallel/0/Config/IRQ" 7

where <VM_NAME> - name of Virtual Machine

Simple

~$ set_vbox_settings <VM_NAME>

where <VM_NAME> - name of Virtual Machine

Links

• Parallel port sniffer (for kernel 2.X)
• Parallel port sniffer (for kernel 3.X)
• Virtual driver for parport(LPT) on linuxquestions.org forum
• VirtualBox Parallel port configuration
• Open Bench Logic Sniffer