Open Source Deep Packet Inspection Software Toolkit: nDPI

nDPI is an open source LGPLv3 library for deep-packet inspection. Based on OpenDPI it includes ntop extensions. We have tried to push them into the OpenDPI source tree but nobody answered emails so we have decided to create our own source tree

How To Compile nDPI

In order to compile this library do

• ./autogen.sh
• ./configure
• make

To run tests do additionally:

• cd tests; ./do.sh

Please note that the pre-requisites for compilation include:

• GNU tools (autogen, automake, autoconf, libtool)
• GNU C compiler (gcc)

How To Add A New Protocol Dissector

The entire procedure of adding new protocols in detail:

1. Add new protocol together with its unique ID to: src/include/ndpi_protocol_ids.h
2. Create a new protocol in: src/lib/protocols/
3. Variables to be kept for the duration of the entire flow (as state variables) need to be placed in: src/include/ndpi_typedefs.h in ndpi_flow_tcp_struct (for TCP only), ndpi_flow_udp_struct (for UDP only), or ndpi_flow_struct (for both).
4. Add a new entry for the search function for the new protocol in: src/include/ndpi_protocols.h
5. Choose (do not change anything) a selection bitmask from: src/include/ndpi_define.h
6. Add a new entry in ndpi_set_protocol_detection_bitmask2 in: src/lib/ndpi_main.c
7. Set protocol default ports in ndpi_init_protocol_defaults in: src/lib/ndpi_main.c
8. ./autogen.sh
9. make
10. make check

How to use nDPI to Block Selected Traffic

You can use nDPI to selectively block selected Internet traffic by embedding it onto an application (remember that nDPI is just a library). Both ntopng and nProbe cento can do this.

Github Project