Crate cddl_cat

This is a library for validating data structures against a CDDL document.

Note: This library is fairly new, and may still contain significant bugs, ommissions, or unstable interfaces.

CDDL is a text document described by RFC8610 that describes data structures. CDDL is not tied to any specific serialization or encoding method; it can be used to validate data that is in CBOR or JSON format.

The goal of this library is to make CBOR or JSON data easy to validate against a CDDL schema description.

Some of the ways this library differs from other implementations:

• An "Intermediate Validation Tree" (ivt) is constructed from the CDDL AST; this removes some of the CDDL syntax detail resulting in a simplified tree that can be more easily validated. The IVT is constructed almost entirely of Node elements, allowing recursive validation.

• Validation is performed by first translating the incoming data into a generic tree form, so the bulk of the validation code is completely agnostic to the serialization format.

An example, validating CBOR-encoded data against a CDDL schema:

use cddl_cat::validate_cbor_bytes;
use serde::Serialize;

#[derive(Serialize)]
struct PersonStruct {
    name: String,
    age: u32,
}

let input = PersonStruct {
    name: "Bob".to_string(),
    age: 43,
};
let cbor_bytes = serde_cbor::to_vec(&input).unwrap();
let cddl_input = "thing = {name: tstr, age: int}";
validate_cbor_bytes("thing", cddl_input, &cbor_bytes).unwrap();

Supported prelude types:

• any, uint, nint, int, bstr, bytes, tstr, text
• float, float16, float32, float64, float16-32, float32-64
  Note: float sizes are not validated.

Unimplemented features:

• Generics
• Non-cut map keys
• Extend type with /=
• Extend group with //=
• Type sockets with $
• Group sockets with $$
• Range operators .., ...
• Control operators, e.g. .size, .bits, ...
• Group enumeration with &
• Tagged data with #
• Literal integers with 0x or 0b
• Hexfloat
• Base64 bytestring literals (b64'...')
• Prelude types that invoke CBOR tags (e.g. tdate or biguint)

Re-exports

pub use cbor::validate_cbor;

pub use cbor::validate_cbor_bytes;

pub use parser::parse_cddl;

Modules

ast	This module defines the Abstract Syntax Tree.
cbor	This module implements validation from serde_cbor::Value.
context	This module defines the Context trait.
flatten	Tools for converting the ast (syntax tree) into an ivt (intermediate validation tree).
ivt	This module defines the Intermediate Validation Tree.
parser	This module contains a CDDL parser.
util	This module defines error and result types.
value	This module declares a generic Value enum for use with validation.