InMon sFlow v5 Parser

A dependency-free Rust library for parsing InMon sFlow version 5 datagrams.

Implementation Status

Main sFlow v5 specification, extensions and discussions are implemented.

Each implemented flow and counter record is covered by a unit test and validated against the official sFlow specification documents.

The flows and counters types tables below list all sFlow structure numbers as defined in the official sFlow structure registry.

Status Legend:

• ✅ Implemented
• ⬜ Not implemented
• 🪦 Deprecated

Specifications

The main specification is sFlow Version 5 from 2004, but many extensions have been published since to support additional monitoring use cases.

Year	Specification	Description	Status
2004	sFlow Version 5	Core protocol, base flow and counter records	✅
2007	sFlow 802.11 Structures	Wireless/802.11 monitoring extensions	✅
2010	sFlow Host Structures	Host and virtual machine performance metrics	✅
2011	sFlow HTTP Structures	HTTP performance metrics	✅
2011	sFlow Java Virtual Machine Structures	JVM performance metrics	✅
2011	sFlow Memcache Structures	Memcache performance metrics	✅
2012	sFlow NVML GPU Structures	NVIDIA GPU performance, status, and health	✅
2012	sFlow Application Structures	Application resource monitoring	✅
2012	sFlow LAG Counters Structure	IEEE 802.1AX Link Aggregation (LACP)	✅
2012	sFlow Tunnel Structures	Encapsulation/decapsulation (VXLAN, GRE, etc.)	✅
2012	sFlow Port NAT Structures	Port-based NAT mapping	✅
2013	sFlow InfiniBand Structures	InfiniBand network monitoring	✅
2014	sFlow OpenFlow Structures	OpenFlow port monitoring	✅
2015	sFlow Host TCP/IP Counters	Host IP, ICMP, TCP, and UDP counters	✅
2015	sFlow Broadcom ASIC Table Utilization	Hardware table utilization for Broadcom ASICs	✅
2015	sFlow Broadcom Buffer Utilization	Buffer utilization for Broadcom switches	✅
2016	sFlow Optical Interface Structures	Pluggable optical modules (SFP, QSFP, etc.)	✅
2020	sFlow Dropped Packet Notification	Reports on dropped packets with reason codes	✅
2021	sFlow Transit Delay Structures	Delay and queue depth for sampled packets	✅

Note: see sFlow Errata for corrections to published specifications.

Sample Types

sFlow datagrams contain sample records. Each sample record has a format type that determines its structure:

Enterprise	Format	Name	Specification	Status
0	1	Flow Sample	sFlow v5	✅
0	2	Counters Sample	sFlow v5	✅
0	3	Flow Sample Expanded	sFlow v5	✅
0	4	Counters Sample Expanded	sFlow v5	✅
0	5	Discarded Packet	sFlow Drops	✅
4300	1002	Custom Metrics	sFlow-RT	✅
4300	1003	Custom Flow Metrics	sFlow-RT	✅

Each sample contains one or more flow records (for flow samples) or counter records (for counter samples).

Flow Records

Enterprise	Format	Name	Specification	Status
0	1	Sampled Header	sFlow v5	✅
0	2	Sampled Ethernet	sFlow v5	✅
0	3	Sampled IPv4	sFlow v5	✅
0	4	Sampled IPv6	sFlow v5	✅
0	1001	Extended Switch	sFlow v5	✅
0	1002	Extended Router	sFlow v5	✅
0	1003	Extended Gateway (BGP)	sFlow v5	✅
0	1004	Extended User	sFlow v5	✅
0	1005	Extended URL (deprecated)	sFlow v5	✅ 🪦
0	1006	Extended MPLS	sFlow v5	✅
0	1007	Extended NAT	sFlow v5	✅
0	1008	Extended MPLS Tunnel	sFlow v5	✅
0	1009	Extended MPLS VC	sFlow v5	✅
0	1010	Extended MPLS FEC	sFlow v5	✅
0	1011	Extended MPLS LVP FEC	sFlow v5	✅
0	1012	Extended VLAN Tunnel	sFlow v5	✅
0	1013	Extended 802.11 Payload	sFlow 802.11	✅
0	1014	Extended 802.11 RX	sFlow 802.11	✅
0	1015	Extended 802.11 TX	sFlow 802.11	✅
0	1016	Extended 802.11 Aggregation	sFlow 802.11	✅
0	1017	Extended OpenFlow v1 (deprecated)	sFlow OpenFlow Draft	✅ 🪦
0	1018	Extended Fibre Channel	RFC 4625	✅
0	1019	Extended Queue Length	sFlow Discussion	✅
0	1020	Extended NAT Port	sFlow Port NAT	✅
0	1021	Extended L2 Tunnel Egress	sFlow Tunnel	✅
0	1022	Extended L2 Tunnel Ingress	sFlow Tunnel	✅
0	1023	Extended IPv4 Tunnel Egress	sFlow Tunnel	✅
0	1024	Extended IPv4 Tunnel Ingress	sFlow Tunnel	✅
0	1025	Extended IPv6 Tunnel Egress	sFlow Tunnel	✅
0	1026	Extended IPv6 Tunnel Ingress	sFlow Tunnel	✅
0	1027	Extended Decapsulate Egress	sFlow Tunnel	✅
0	1028	Extended Decapsulate Ingress	sFlow Tunnel	✅
0	1029	Extended VNI Egress	sFlow Tunnel	✅
0	1030	Extended VNI Ingress	sFlow Tunnel	✅
0	1031	Extended InfiniBand LRH	sFlow InfiniBand	✅
0	1032	Extended InfiniBand GRH	sFlow InfiniBand	✅
0	1033	Extended InfiniBand BTH	sFlow InfiniBand	✅
0	1034	Extended VLAN In	sFlow Discussion	✅
0	1035	Extended VLAN Out	sFlow Discussion	✅
0	1036	Extended Egress Queue	sFlow Drops	✅
0	1037	Extended ACL	sFlow Drops	✅
0	1038	Extended Function	sFlow Drops	✅
0	1039	Extended Transit Delay	sFlow Transit	✅
0	1040	Extended Queue Depth	sFlow Transit	✅
0	1041	Extended HW Trap	host-sflow Implementation	✅
0	1042	Extended Linux Drop Reason	host-sflow Implementation	✅
0	2000	Transaction	sFlow Discussion	✅
0	2001	Extended NFS Storage Transaction	sFlow Discussion	✅
0	2002	Extended SCSI Storage Transaction	sFlow Discussion	✅
0	2003	Extended HTTP Transaction	sFlow Discussion	✅
0	2100	Extended Socket IPv4	sFlow Host	✅
0	2101	Extended Socket IPv6	sFlow Host	✅
0	2102	Extended Proxy Socket IPv4	sFlow HTTP	✅
0	2103	Extended Proxy Socket IPv6	sFlow HTTP	✅
0	2200	Memcache Operation	sFlow Memcache	✅
0	2201	HTTP Request (deprecated)	sFlow Discussion	✅ 🪦
0	2202	App Operation	sFlow Application	✅
0	2203	App Parent Context	sFlow Application	✅
0	2204	App Initiator	sFlow Application	✅
0	2205	App Target	sFlow Application	✅
0	2206	HTTP Request	sFlow HTTP	✅
0	2207	Extended Proxy Request	sFlow HTTP	✅
0	2208	Extended Nav Timing	sFlow Discussion	✅
0	2209	Extended TCP Info	sFlow Discussion	✅
0	2210	Extended Entities	sFlow Discussion	✅
4413	1	BST Egress Queue	sFlow Broadcom	✅

Counter Records

Enterprise	Format	Name	Specification	Status
0	1	Generic Interface	sFlow v5	✅
0	2	Ethernet Interface	sFlow v5	✅
0	3	Token Ring	sFlow v5	✅
0	4	100BaseVG Interface	sFlow v5	✅
0	5	VLAN	sFlow v5	✅
0	6	IEEE 802.11 Counters	sFlow 802.11	✅
0	7	LAG Port Stats	sFlow LAG	✅
0	8	Slow Path Counts	sFlow Discussion	✅
0	9	InfiniBand Counters	sFlow InfiniBand	✅
0	10	Optical SFP/QSFP	sFlow Optics	✅
0	1001	Processor	sFlow v5	✅
0	1002	Radio Utilization	sFlow 802.11	✅
0	1003	Queue Length	sFlow Discussion	✅
0	1004	OpenFlow Port	sFlow OpenFlow	✅
0	1005	OpenFlow Port Name	sFlow OpenFlow	✅
0	2000	Host Description	sFlow Host	✅
0	2001	Host Adapters	sFlow Host	✅
0	2002	Host Parent	sFlow Host	✅
0	2003	Host CPU	sFlow Host	✅
0	2004	Host Memory	sFlow Host	✅
0	2005	Host Disk I/O	sFlow Host	✅
0	2006	Host Network I/O	sFlow Host	✅
0	2007	MIB2 IP Group	sFlow Host TCP/IP	✅
0	2008	MIB2 ICMP Group	sFlow Host TCP/IP	✅
0	2009	MIB2 TCP Group	sFlow Host TCP/IP	✅
0	2010	MIB2 UDP Group	sFlow Host TCP/IP	✅
0	2100	Virtual Node	sFlow Host	✅
0	2101	Virtual CPU	sFlow Host	✅
0	2102	Virtual Memory	sFlow Host	✅
0	2103	Virtual Disk I/O	sFlow Host	✅
0	2104	Virtual Network I/O	sFlow Host	✅
0	2105	JVM Runtime	sFlow JVM	✅
0	2106	JVM Statistics	sFlow JVM	✅
0	2200	Memcache Counters (deprecated)	sFlow Discussion	✅ 🪦
0	2201	HTTP Counters	sFlow HTTP	✅
0	2202	App Operations	sFlow Application	✅
0	2203	App Resources	sFlow Application	✅
0	2204	Memcache Counters	sFlow Memcache	✅
0	2206	App Workers	sFlow Application	✅
0	2207	OVS DP Stats	sFlow Discussion	✅
0	3000	Energy	sFlow Discussion	✅
0	3001	Temperature	sFlow Discussion	✅
0	3002	Humidity	sFlow Discussion	✅
0	3003	Fans	sFlow Discussion	✅
4413	1	Broadcom Device Buffer	sFlow Broadcom	✅
4413	2	Broadcom Port Buffer	sFlow Broadcom	✅
4413	3	Broadcom ASIC Tables	sFlow Broadcom	✅
5703	1	NVIDIA GPU	sFlow NVML	✅

Serialization / Deserialization Support

Enables optional serialization and deserialization support for all sFlow data structures using serde. This allows you to easily convert parsed sFlow data to and from JSON, YAML, or any other format supported by serde.

[dependencies]
sflow-parser = { version = "0.3", features = ["serde"] }
serde_json = "1.0"

Example usage:

use sflow_parser::parse_datagram;

let datagram = parse_datagram(&data)?;

// Serialize to JSON
let json = serde_json::to_string(&datagram)?;

// Deserialize from JSON
let datagram: SFlowDatagram = serde_json::from_str(&json)?;

Testing

Unit & Integration Tests

Run the comprehensive test suite:

make test              # Run all tests
make test-unit         # Run unit tests only
make test-integration  # Run integration tests only

Fuzz Tests

The project includes comprehensive fuzz testing using cargo-fuzz:

make fuzz-install     # Install fuzzing tools (requires nightly Rust)
make fuzz-single      # Fuzz single datagram parsing (60s)
make fuzz-multiple    # Fuzz multiple datagrams parsing (60s)
make fuzz-structured  # Fuzz with structured inputs (60s)
make fuzz-all         # Run all fuzzers (5 minutes each)

Specifications Validation

The project includes comprehensive validation against official sFlow specification documents using syn crate to parse Rust source files and extract sFlow struct metadata:

make specs-validate

This validation allowed us to identify additional specification issues that are not yet part of the official errata.

Benchmarks

Performance benchmarks using Criterion:

make bench

Results: ~150ns per datagram (~750.45 MiB/s throughput) on typical hardware. The parser is not zero-copy (at least for now) and does not use any unsafe code, but it is fast enough for most use cases.

License

This project is licensed under the MIT License.

sFlow® is a registered trademark of InMon Corp. This implementation is based on the sFlow version 5 specification available at https://sflow.org/sflow_version_5.txt and is licensed under the terms provided at https://inmon.com/technology/sflowlicense.txt.