C2PA Rust SDK

The Coalition for Content Provenance and Authenticity (C2PA) addresses the prevalence of misleading information online through the development of technical standards for certifying the source and history (or provenance) of media content. Adobe and other contributors created the C2PA Rust SDK as part of the Content Authenticity Initiative and released it to open source in June, 2022.

Key features

The C2PA Rust SDK implements a subset of the C2PA 1.0 technical specification.

The SDK enables a desktop, mobile, or embedded application to:

• Create and sign C2PA claims and manifests.
• Embed manifests in certain file formats.
• Parse and validate manifests found in certain file formats.

The SDK supports several common C2PA assertions and hard bindings.

State of the project

This is an early release (version 0.x.x) of the project. The minor version number (0.x.0) is incremented when there are breaking API changes, which may happen frequently.

The SDK:

• Supports a variety of image and video formats. For details, see c2patool supported file formats.
• Does not parse identity structures (verifiable credentials).

Contributions and feedback

We welcome contributions to this project. For information on contributing, providing feedback, and about ongoing work, see Contributing.

Requirements

The SDK requires Rust version 1.63.0 or newer.

Supported platforms

The SDK has been tested on the following operating systems:

• Windows
• MacOS (Intel and Apple silicon)
• Ubuntu Linux
• WebAssembly (Wasm); NOTE: claim generation is not available on Wasm.

Usage

Add this to your Cargo.toml:

[dependencies]
c2pa = "0.19.0"

If you want to read or write a manifest file, add the file_io dependency to your Cargo.toml. For example:

c2pa = { version = "0.11.0", features = ["file_io"] }

NOTE: If you are building for WASM, omit the file_io dependency.

Crate features

The Rust SDK crate provides:

• file_io enables manifest generation, signing via OpenSSL, and embedding manifests in various file formats.
• serialize_thumbnails includes binary thumbnail data in the Serde serialization output.
• xmp_write enables updating XMP on embed with the dcterms:provenance field. (Requires xmp_toolkit.)
• no_interleaved_io forces fully-synchronous I/O; otherwise, the SDK uses threaded I/O for some operations to improve performance.
• fetch_remote_manifests enables the verification step to retrieve externally referenced manifest stores. External manifests are only fetched if there is no embedded manifest store and no locally adjacent .c2pa manifest store file of the same name.

License

The c2pa crate is distributed under the terms of both the MIT license and the Apache License (Version 2.0).

Note that some components and dependent crates are licensed under different terms; please check the license terms for each crate and component for details.