go-pfcp
PFCP implementation in Golang.
What is PFCP?
PFCP(Packet Forwarding Control Protocol) is a signaling protocol used in mobile networking infrastructure(LTE EPC, 5GC) to realize CUPS architecture(Control and User Plane Separation, not a printing system).
Looking for GTP implementation in Golang? go-gtp would be a good choice for you :P
Project Status
This project is still WIP; I'm in the middle of implementing messages and IEs, networking functionalities(like setting up associations) are not available currently.
Getting Started
Installation
go-pfcp supports Go Modules. Just run go mod tidy in your project's directory to collect required packages automatically.
go mod tidy
If your Go version is older than 1.11, run go get manually the following packages instead.
go get -u github.com/google/go-cmp
go get -u github.com/pascaldekloe/goe
Running examples
Exchanging Heartbeat
Small examples of Heartbeat client and server is available under examples/heartheat. Client sends HeartbeatRequest and server respond with HeartbeatResponse.
- run server first,
By default server listens on loopback. It can be specified explicitly by -s flag.
go-pfcp/examples/heartbeat/hb-server$ go run main.go
2019/12/22 20:03:31 waiting for messages to come on: 127.0.0.2:8805
- then run client,
By default client sends Heartbeat to loopback. It can be specified explicitly by -s flag.
It exits after printing timestamp in Heartbeat Response from server.
go-pfcp/examples/heartbeat/hb-client$ go run main.go
2019/12/22 20:03:36 sent Heartbeat Request to: 127.0.0.2:8805
2019/12/22 20:03:36 got Heartbeat Response with TS: 2019-12-22 20:03:36 +0900 JST, from: 127.0.0.2:8805
go-pfcp/examples/heartbeat/hb-client$
go-pfcp/examples/heartbeat/hb-client$ go run main.go
2019/12/22 20:03:40 sent Heartbeat Request to: 127.0.0.2:8805
2019/12/22 20:03:40 got Heartbeat Response with TS: 2019-12-22 20:03:40 +0900 JST, from: 127.0.0.2:8805
- and see the outcome on server
It starts listening again after responding to client.
go-pfcp/examples/heartbeat/hb-server$ go run main.go
2019/12/22 20:03:31 waiting for messages to come on: 127.0.0.2:8805
2019/12/22 20:03:36 got Heartbeat Request with TS: 2019-12-22 20:03:36 +0900 JST, from: 127.0.0.1:47305
2019/12/22 20:03:36 sent Heartbeat Response to: 127.0.0.1:47305
2019/12/22 20:03:36 waiting for messages to come on: 127.0.0.2:8805
2019/12/22 20:03:40 got Heartbeat Request with TS: 2019-12-22 20:03:40 +0900 JST, from: 127.0.0.1:55395
2019/12/22 20:03:40 sent Heartbeat Response to: 127.0.0.1:55395
2019/12/22 20:03:40 waiting for messages to come on: 127.0.0.2:8805
^Csignal: interrupt
Supported Features
Messages
PFCP Node related messages
| Message Type | Message | Sxa | Sxb | Sxc | N4 | Supported? |
|---|---|---|---|---|---|---|
| 1 | Heartbeat Request | X | X | X | X | Yes |
| 2 | Heartbeat Response | X | X | X | X | Yes |
| 3 | PFD Management Request | - | X | X | X | |
| 4 | PFD Management Response | - | X | X | X | |
| 5 | Association Setup Request | X | X | X | X | |
| 6 | Association Setup Response | X | X | X | X | |
| 7 | Association Update Request | X | X | X | X | |
| 8 | Association Update Response | X | X | X | X | |
| 9 | Association Release Request | X | X | X | X | |
| 10 | Association Release Response | X | X | X | X | |
| 11 | Version Not Supported Response | X | X | X | X | |
| 12 | Node Report Request | X | X | X | X | |
| 13 | Node Report Response | X | X | X | X | |
| 14 | Session Set Deletion Request | X | X | - | ||
| 15 | Session Set Deletion Response | X | X | - | ||
| 16 to 49 | (For future use) | - |
PFCP Session related messages
| Message Type | Message | Sxa | Sxb | Sxc | N4 | Supported? |
|---|---|---|---|---|---|---|
| 50 | Session Establishment Request | X | X | X | X | |
| 51 | Session Establishment Response | X | X | X | X | |
| 52 | Session Modification Request | X | X | X | X | |
| 53 | Session Modification Response | X | X | X | X | |
| 54 | Session Deletion Request | X | X | X | X | |
| 55 | Session Deletion Response | X | X | X | X | |
| 56 | Session Report Request | X | X | X | X | |
| 57 | Session Report Response | X | X | X | X | |
| 58 to 99 | (For future use) | - |
Information Elements
| IE Type | Information elements | Supported? |
|---|---|---|
| 0 | (Reserved) | - |
| 1 | Create PDR | |
| 2 | PDI | |
| 3 | Create FAR | |
| 4 | Forwarding Parameters | |
| 5 | Duplicating Parameters | |
| 6 | Create URR | |
| 7 | Create QER | |
| 8 | Created PDR | |
| 9 | Update PDR | |
| 10 | Update FAR | |
| 11 | Update Forwarding Parameters | |
| 12 | Update BAR (Sx Session Report Response) | |
| 13 | Update URR | |
| 14 | Update QER | |
| 15 | Remove PDR | |
| 16 | Remove FAR | |
| 17 | Remove URR | |
| 18 | Remove QER | |
| 19 | Cause | Yes |
| 20 | Source Interface | Yes |
| 21 | F-TEID | Yes |
| 22 | Network Instance | Yes |
| 23 | SDF Filter | |
| 24 | Application ID | Yes |
| 25 | Gate Status | Yes |
| 26 | MBR | Yes |
| 27 | GBR | Yes |
| 28 | QER Correlation ID | Yes |
| 29 | Precedence | Yes |
| 30 | Transport Level Marking | Yes |
| 31 | Volume Threshold | Yes |
| 32 | Time Threshold | Yes |
| 33 | Monitoring Time | Yes |
| 34 | Subsequent Volume Threshold | Yes |
| 35 | Subsequent Time Threshold | Yes |
| 36 | Inactivity Detection Time | Yes |
| 37 | Reporting Triggers | Yes |
| 38 | Redirect Information | Yes |
| 39 | Report Type | Yes |
| 40 | Offending IE | Yes |
| 41 | Forwarding Policy | Yes |
| 42 | Destination Interface | Yes |
| 43 | UP Function Features | Yes |
| 44 | Apply Action | Yes |
| 45 | Downlink Data Service Information | Yes |
| 46 | Downlink Data Notification Delay | Yes |
| 47 | DL Buffering Duration | Yes |
| 48 | DL Buffering Suggested Packet Count | Yes |
| 49 | SxSMReq-Flags | Yes |
| 50 | SxSRRsp-Flags | Yes |
| 51 | Load Control Information | |
| 52 | Sequence Number | Yes |
| 53 | Metric | Yes |
| 54 | Overload Control Information | |
| 55 | Timer | Yes |
| 56 | Packet Detection Rule ID | Yes |
| 57 | F-SEID | Yes |
| 58 | Application ID's PFDs | |
| 59 | PFD context | |
| 60 | Node ID | |
| 61 | PFD contents | |
| 62 | Measurement Method | |
| 63 | Usage Report Trigger | |
| 64 | Measurement Period | |
| 65 | FQ-CSID | |
| 66 | Volume Measurement | |
| 67 | Duration Measurement | |
| 68 | Application Detection Information | |
| 69 | Time of First Packet | |
| 70 | Time of Last Packet | |
| 71 | Quota Holding Time | |
| 72 | Dropped DL Traffic Threshold | |
| 73 | Volume Quota | |
| 74 | Time Quota | |
| 75 | Start Time | |
| 76 | End Time | |
| 77 | Query URR | |
| 78 | Usage Report (in Session Modification Response) | |
| 79 | Usage Report (Session Deletion Response) | |
| 80 | Usage Report (Session Report Request) | |
| 81 | URR ID | |
| 82 | Linked URR ID | |
| 83 | Downlink Data Report | |
| 84 | Outer Header Creation | |
| 85 | Create BAR | |
| 86 | Update BAR (Session Modification Request) | |
| 87 | Remove BAR | |
| 88 | BAR ID | |
| 89 | CP Function Features | |
| 90 | Usage Information | |
| 91 | Application Instance ID | |
| 92 | Flow Information | |
| 93 | UE IP Address | |
| 94 | Packet Rate | |
| 95 | Outer Header Removal | |
| 96 | Recovery Time Stamp | |
| 97 | DL Flow Level Marking | |
| 98 | Header Enrichment | |
| 99 | Error Indication Report | |
| 100 | Measurement Information | |
| 101 | Node Report Type | |
| 102 | User Plane Path Failure Report | |
| 103 | Remote GTP-U Peer | |
| 104 | UR-SEQN | |
| 105 | Update Duplicating Parameters | |
| 106 | Activate Predefined Rules | |
| 107 | Deactivate Predefined Rules | |
| 108 | FAR ID | |
| 109 | QER ID | |
| 110 | OCI Flags | |
| 111 | Sx Association Release Request | |
| 112 | Graceful Release Period | Yes |
| 113 | PDN Type | |
| 114 | Failed Rule ID | |
| 115 | Time Quota Mechanism | |
| 116 | User Plane IP Resource Information | |
| 117 | User Plane Inactivity Timer | |
| 118 | Aggregated URRs | |
| 119 | Multiplier | |
| 120 | Aggregated URR ID | |
| 121 | Subsequent Volume Quota | |
| 122 | Subsequent Time Quota | |
| 123 | RQI | |
| 124 | QFI | |
| 125 | Query URR Reference | |
| 126 | Additional Usage Reports Information | |
| 127 | Create Traffic Endpoint | |
| 128 | Created Traffic Endpoint | |
| 129 | Update Traffic Endpoint | |
| 130 | Remove Traffic Endpoint | |
| 131 | Traffic Endpoint ID | |
| 132 | Ethernet Packet Filter | |
| 133 | MAC address | |
| 134 | C-TAG | |
| 135 | S-TAG | |
| 136 | Ethertype | |
| 137 | Proxying | |
| 138 | Ethernet Filter ID | |
| 139 | Ethernet Filter Properties | |
| 140 | Suggested Buffering Packets Count | |
| 141 | User ID | |
| 142 | Ethernet PDU Session Information | |
| 143 | Ethernet Traffic Information | |
| 144 | MAC Addresses Detected | |
| 145 | MAC Addresses Removed | |
| 146 | Ethernet Inactivity Timer | |
| 147 | Additional Monitoring Time | |
| 148 | Event Quota | |
| 149 | Event Threshold | |
| 150 | Subsequent Event Quota | |
| 151 | Subsequent Event Threshold | |
| 152 | Trace Information | |
| 153 | Framed-Route | |
| 154 | Framed-Routing | |
| 155 | Framed-IPv6-Route | |
| 156 | Event Time Stamp | |
| 157 | Averaging Window | |
| 158 | Paging Policy Indicator | |
| 159 | APN/DNN | |
| 160 | 3GPP Interface Type | |
| 161 | PFCPSRReq-Flags | |
| 162 | PFCPAUReq-Flags | |
| 163 | Activation Time | |
| 164 | Deactivation Time | |
| 165 | Create MAR | |
| 166 | Access Forwarding Action Information 1 | |
| 167 | Access Forwarding Action Information 2 | |
| 168 | Remove MAR | |
| 169 | Update MAR | |
| 170 | MAR ID | |
| 171 | Steering Functionality | |
| 172 | Steering Mode | |
| 173 | Weight | |
| 174 | Priority | |
| 175 | Update Access Forwarding Action Information 1 | |
| 176 | Update Access Forwarding Action Information 2 | |
| 177 | UE IP address Pool Identity | |
| 178 | Alternative SMF IP Address | |
| 179 | Packet Replication and Detection Carry-On Information | |
| 180 | SMF Set ID | |
| 181 | Quota Validity Time | |
| 182 to 65535 | (Spare. For future use.) | - |
Disclaimer
This is still an experimental project. Any part of implementations(including exported APIs) may be changed before released as v1.0.0.
Author(s)
Yoshiyuki Kurauchi (Website / LinkedIn)
I'm always open to welcome co-authors! Please feel free to talk to me.