DSSE: Dead Simple Signing Envelope

Simple, foolproof standard for signing arbitrary data.

Features

• Supports arbitrary message encodings, not just JSON.
• Authenticates the message and the type to avoid confusion attacks.
• Avoids canonicalization to reduce attack surface.
• Allows any desired crypto primitives or libraries.

See Background for more information, including design considerations and rationale.

What is it?

Specifications for:

• Protocol (required)
• Data structure, a.k.a. "Envelope" (recommended)
• (pending #9) Suggested crypto primitives

Out of scope (for now at least):

• Key management / PKI / exclusive ownership

Why not...?

• Why not raw signatures? Too fragile.
• Why not JWS? Too many insecure implementations and features.
• Why not PASETO? JSON-specific, too opinionated.
• Why not the legacy TUF/in-toto signature scheme? JSON-specific, relies on canonicalization.

See Background for further motivation.

Who uses it?

• in-toto (pending implementation of ITE-5)
• TUF (pending implementation of TAP-17)

How can we use it?

• There is a Python implementation in this repository.
• There's a DSSE library for Go in go-securesystemslib.
• SigStore includes a Go implementation that supports hardware tokens, cloud KMS systems, and more.