Tauri Plugin: p256-signer

Sign messages from a Tauri app using platform passkeys (WebAuthn). This plugin exposes a small JS API that serializes WebAuthn requests to be handled by the native layer and returns a parsed PublicKeyCredential which can be used to build viem/web3-style accounts (for example a webauthn-p256 owner for account abstraction / 4337 flows).

This repository contains:

• Rust plugin code for Tauri (the native implementation).
• JS bindings (lightweight helpers) in guest-js/ and a distributable bundle in dist-js/.

Key notes

• The plugin does not bypass the platform security model: you must configure the consuming Android/iOS application to allow WebAuthn/passkey use. On Android this normally means adding an assetlinks JSON entry hosted at your domain and verifying your package name / signing certificate. On iOS you need properly configured Associated Domains and, where relevant, App Clip/entitlements.

Use this plugin when you want to let a Tauri desktop/mobile app create and use WebAuthn passkeys and surface the resulting signatures/public keys to a JS layer (for example to construct viem accounts).

Quick install

This project publishes JS bindings as the package @metasig/tauri-plugin-p256-signer-api (see package.json). To use the JS helpers in your Tauri app, install the package (npm / pnpm / yarn):

# from your app's frontend
pnpm add @metasig/tauri-plugin-p256-signer-api

The native plugin is a standard Tauri plugin. Include it in your Tauri Rust plugin list and enable the plugin during build. See "Build & develop" below for local build instructions.

Usage (JS example)

The JS bindings expose two high-level helpers: createCredential and getCredential. They serialize WebAuthn options into a JSON-friendly form, invoke the native plugin and return a parsed PublicKeyCredential object that behaves like the browser API.

Example (browser/guest code):

import { createCredential, getCredential } from '@metasig/tauri-plugin-p256-signer-api';

// Create a credential from PublicKeyCredentialCreationOptions
const created = await createCredential(creationOptions);

// Request an assertion
const asserted = await getCredential({ publicKey: requestOptions });

// Use asserted.response.signature and asserted.rawId in your app (for example to register a
// viem webauthn-p256 account or to verify a signature server-side).

For more advanced usage and the exact serialization/parsing behavior, see guest-js/index.ts in this repository.

Build & develop

From the repository root you can build both the JS bundle and the Rust plugin.

• Build JS bundle:

pnpm build

• Build Rust plugin (requires Rust >= 1.77.2):

cargo build --release

License

This repository is licensed under Apache-2.0 (see package.json).