Implement simple traffic test for spwgu using pcapplusplus

[navarrothiago]

The ideia is to craft a simple G_PDU packet and inject it in spgwu gtpu stack e check the answer.
Check destination interfaces in section 8.2.24 in TS 129 244.

• Send G_PDU and forward it to SGi

To sum up, test consist in :

• Send Session establishment request to spgwu
  • Create Create PDR IE
  • Create Create FAR IE
  • Create PDI IE
• Check the response of the request
• Check TEID allocated
• Start capture from interface SGi using pcapplusplus based on tutorial
• Create a IP packet
• Encapsulate IP Packet in GTP GPDU
• Inject the crafted packet in GTP stack in spgwu by sending to the server UDP
  • Pass allocated TEID in call function
• Analyse the captured packet if its field matchs with the parameters (e.g. destination address)

Refs:

• https://www.etsi.org/deliver/etsi_ts/129200_129299/129244/15.07.00_60/ts_129244v150700p.pdf
• https://www.etsi.org/deliver/etsi_ts/129200_129299/129281/15.04.00_60/ts_129281v150400p.pdf
• https://pcapplusplus.github.io/docs/
• https://github.com/navarrothiago/openair-uml/blob/master/imgs/fig160642.png
• https://github.com/navarrothiago/openair-uml/blob/master/imgs/fig147586.png