Tessio.Verifier.Core 0.1.5

Tessio.Verifier

The .NET / ASP.NET Core verifier for the EU Digital Identity (EUDI) Wallet.

Verify credentials presented by EUDI Wallets directly from your .NET backend, over OpenID4VP 1.0 with SD-JWT VC credentials. Native to ASP.NET Core and Azure, with a built-in demo mode so you can run a full verification flow today, before any production wallet ships.

Relying-party (verifier) side only. This library never acts as a wallet or an issuer.

Status: the full pipeline runs on main. The quickstart below works end to end. Mock mode exercises the real protocol path with a built-in wallet, Test mode replays the RFC 9901 conformance vector through the real verifier and Live mode waits for real wallets on the callback endpoint (see the going-live guide). Version 0.1.4 is on NuGet now. Follow releases for progress.

Why this exists

The EUDI Wallet arrives under Regulation (EU) 2024/1183: member states must make wallets available by December 2026, and regulated relying parties must accept them by December 2027. The open-source verifier tooling today is Kotlin (walt.id), Rust (SpruceID), and TypeScript (OpenEUDI). If you run on .NET, there hasn't been a native option. This is it.

What you get (v0.1)

• OpenID4VP 1.0 verifier flow (cross-device / QR), DCQL queries, JAR-signed requests (RFC 9101)
• SD-JWT VC verification: issuer signature (JWT VC Issuer Metadata and X.509), selective disclosure, key binding (KB-JWT)
• DEMO / MOCK / TEST modes so you can build before wallets exist
• Idiomatic ASP.NET Core integration (DI + minimal APIs) and a runnable sample
• A pluggable trust seam (ITrustListResolver) for production trust lists

Install

dotnet add package Tessio.Verifier.AspNetCore

Quickstart — 5 minutes, DEMO mode

var builder = WebApplication.CreateBuilder(args);

builder.Services.AddTessioVerifier(options =>
{
    options.Mode = VerifierMode.Demo;          // auto-completes locally, no real wallet needed
    options.RequestedClaims = ["age_over_18"]; // selective disclosure: ask only for what you need
});

var app = builder.Build();

app.MapTessioVerifier();   // request-init, wallet-callback, and result-stream (SSE) endpoints

app.MapGet("/", () => Results.Content(
    """<a href="/verify/start">Start a verification</a>""", "text/html"));

app.Run();

Run it, open the page, start a verification, and DEMO mode returns a verified age_over_18 claim over Server-Sent Events.

Modes

• Demo: auto-completes in seconds, for showcases and first-run experience.
• Mock: a built-in mock wallet posts freshly signed credentials through the full verification pipeline, encrypted responses included.
• Test: replays the RFC 9901 conformance vector (the spec's German PID example) through the real verifier, so you see the verifier agree with the specification's own bytes.
• Live: sessions wait for real wallets on the callback endpoint. docs/going-live.md covers the setup: signed requests, trust lists, session stores and response encryption.

Packages

Going to production

docs/going-live.md walks through the code side: signed requests (Key Vault/HSM included), real trust lists, distributed session stores and shared response-encryption keys. Beyond the code, live verification against real wallets requires a registered Relying Party and a WRPAC (Wallet Relying Party Access Certificate) from a Qualified Trust Service Provider, plus maintained EU trust lists. This library handles the protocol and credential verification. The trust and compliance layer is provided separately (see docs/production.md). Relying parties do not need their own HSM/QSCD, since the QTSP holds those.

Standards

• OpenID4VP 1.0 — https://openid.net/specs/openid-4-verifiable-presentations-1_0.html
• SD-JWT VC — https://datatracker.ietf.org/doc/html/draft-ietf-oauth-sd-jwt-vc
• EUDI Architecture & Reference Framework — https://github.com/eu-digital-identity-wallet/eudi-doc-architecture-and-reference-framework
• WRPAC profile — ETSI TS 119 475

Repository

• Source: https://github.com/tripledownab/tessio-verifier
• Issues: https://github.com/tripledownab/tessio-verifier/issues
• Releases: https://github.com/tripledownab/tessio-verifier/releases

License

Apache-2.0