upf_p4_poc

This project is a proof of concept for 5g upf based on p4. The project uses open source project to verify key technologies, such as pfcp, p4runtime RPC and programmable dataplane pipeline.

Related open source projects

1. go-pfcp https://github.com/wmnsk/go-pfcp
   PFCP implementation in Golang.This project use go-pfcp to decode/code pfcp message.
2. p4runtime-go-client https://github.com/antoninbas/p4runtime-go-client
   Go client for P4Runtime.This project use p4runtime-go-client to connect stratum_bmv2(as swithos and pipeline instance),config pipeline and insert table entry.
3. scapy https://github.com/secdev/scapy
   Scapy is a powerful Python-based interactive packet manipulation program and library. This project use it to construct and send PFCP request messages.I also use it to send user plane uplink and downlink data packets for function test.
4. ngsdn-tutorial https://github.com/opennetworkinglab/ngsdn-tutorial
   Tutorial for Next-generation SDN (NG-SDN).It contains a set of containers, such as p4c, mininet(include stratum-bmv2), onos. Use it as a p4 compilation and test runtime environment.

What is UPF?

The User Plane Function (UPF) is a fundamental component of a 3GPP 5G core infrastructure system architecture. It acts as a gateway between the base station and the data network.The UPF identifies user plane traffic flow and action based on information received from control plane network function(as SMF in 5g).
PFCP(Packet Forwarding Control Protocol) used in CP NF to control UPF,it defined in 3GPP TS29.244. It is similar to OpenFlow. Maybe consider it as the southbound interface of the dataplane in the mobile networks. Packet processing flow in the UP function(ps:I think this processing flow is just an ideal definition, and there are multiple implementations ^_^)
The GTP (GPRS Tunnelling Protocol) protocol provides protocol channels between mobile access network and core network. All UE access DN should be encapsulated by the GTP protocol.
GTP-U header. User plane protocol stack for a PDU session

Requirements

OS:Ubuntu 18.04
Go (>= 1.14)
ps:maybe need to set proxy getting package,like me

export GO111MODULE=on
export GOPROXY=https://goproxy.cn

docker docker-compose git python2.7 make ...

Getting Started

1.Download and Prepare the environment.(one time) Note：It will take some time to download docker images.

git clone 
make deps-env

2.Build The result in "build" folder.

make build

3.Runing The components of poc Start stratum environment,include mininet.see aslo ngsdn-tutorial .

cd ./ngsdn-tutorial
make start

Start cp-upf
Note：replace param as your environment.

cd ./build
./cp-upf --addr ${STRATUMIP}:${STRATUMPORT} -bin bmv2.json -p4info p4info.txt -device-id 1 -n4addr {N4IP}:{N4PORT}

4.Test Mininet config ip and downlink route by hands.

cd ./ngsdn-tutorial
make mn-cli
mininet> h1a ip addr add 193.168.1.2/24 dev h1a-eth0
mininet> h1b ip addr add 193.168.1.3/24 dev h1b-eth0
mininet> h1b ip route add  10.10.10.2/32 via 193.168.1.2

Send PFCP request to create pdu session.The cp-upf receive pfcp messages will translate to some p4table operations. Note:need to modify ip in the scripts based on run environment.

./test_script/pfcp_request.py

Send gtpu uplink

cd ./ngsdn-tutorial
util/mn-cmd h1a python /mininet/send_gtp_uplink.py
util/mn-cmd h1a tcpdump -i h1a-eth0 -w /tmp/uplink-ue.pcap
util/mn-cmd h1b tcpdump -i h1b-eth0 -w /tmp/uplink-dn.pcap

Send gtpu downlink

util/mn-cmd h1b python /mininet/send_udp_downlink.py
util/mn-cmd h1a tcpdump -i h1a-eth0 -w /tmp/downlink-ue.pcap
util/mn-cmd h1b tcpdump -i h1b-eth0 -w /tmp/downlink-dn.pcap

Planning

Add more counter and connect to onos.
Add packout to cpu and dpi.
Also I have a plan to coding upf poc based on ebpf(xdp).that will be another story,but all of them will be one story.