Crate c_its_parser 

Parser and encoder for ETSI C-ITS (V2X) messages including GeoNetworking headers and optionally Radiotap and IEEE 802.11 headers. It supports UPER, XER and JER ASN.1 encodings for parsing and encoding.

Supported messages/ standards: See documentation of the ItsMessage variants.

Decoding

A packet can be decoded using the de::decode function:

let data = &[0x02, 0x02, 0xde, 0x14, 0x0c, 0xe5]; // provide actual message buffer here
#[cfg(feature = "_etsi")]
match c_its_parser::de::decode(data, c_its_parser::Headers::RadioTap802LlcGnBtp) {
    #[cfg(feature = "cam_1_4_1")]
    Ok(c_its_parser::ItsMessage::Cam {
        geonetworking: _,
        transport: _,
        etsi: cam,
    }) => {
        println!("Got a CAM: {cam:?}")
    }
    Ok(msg) => println!("Got: {msg:?}"),
    Err(err) => println!("Failed to parse message: {err}"),
}

The headers argument needs to specify which headers are present: None, GeoNetworking + BTP or Radiotap + 802.11p + LLC + GeoNetworking + BTP. Headers are expected to be present in binary form. When no headers are present, it can auto-detect the ASN.1 encoding (UPER/ XER/ JER) and decodes the message. This means, that XER and JER message buffers can only be decoded without headers.

Encoding

To encode an ItsMessage struct, call the encode() method supplying the intended encoding rules. Again, XER and JER messages can only be encoded without headers. GeoNetworking and transport (BTP) headers will be added when present if UPER encoding is used.

Feature Flags

This library has several feature flags to allow fine-grained control over the feature set and additional dependencies.

By default, all V2X messages and conversion to and from JSON are enabled. If only some messages, or even just specific versions of messages are needed, they can be enabled one-by-one, e.g. using denm to enable both denm_1_3_1 and denm_2_2_1 support.

When no parsing of the geonetworking and pcap headers is needed, the transport feature can be disabled.

Besides parsing, the Rust API also provides helper functions to convert between ETSI data types and “normal”/ SI units. Additional conversions are only available by adding some feature flags:

• time: Enable conversions to chrono timestamps
• geo: Enable conversions to geo-types (as lon/lat coordinates in degrees)

Modules

de

C-ITS Message Decoding

en

C-ITS Message Encoding

standards

C-ITS ASN.1 Message Definitions and Utilities

transport

GeoNetworking Transport Layer Parser

Enums

EncodingRules

Choice of ASN.1 encoding rule

Headers

Choice which message headers are present in the binary message buffer

ItsMessage

Wrapper for C-ITS messages

Packet

Traits

Decode

Functions

remove_pcap_headers

Strips Radiotap, IEEE 802.11p and LLC headers from a binary message buffer