bcx-crypto

Crypto-agile signature envelope metadata for the main bcx crate.

This crate belongs to the BCX workspace. It is published separately so the main crate can keep small internal modules and precise dependency boundaries, but it is not meant to be used as a standalone protocol product. Prefer depending on bcx unless you are working on BCX internals.

Example

use bcx_core::Digest;
use bcx_crypto::{ExactAlgorithmPolicy, SignatureAlgorithm, SignatureEnvelope};
use bcx_wire::WireLimits;

let signature = [7; SignatureAlgorithm::ED25519_SIGNATURE_LEN];
let limits = WireLimits::new(64 * 1024, 16, 5, 100).unwrap();
let envelope = SignatureEnvelope::new(
    Digest::new([1; Digest::LEN]),
    SignatureAlgorithm::Ed25519,
    &signature,
    limits,
)
.unwrap();
let policy = ExactAlgorithmPolicy::new(SignatureAlgorithm::Ed25519);

assert!(policy.admits(envelope.algorithm()));

Notes

• no_std by default.
• This crate defines metadata and verifier traits, not cryptographic provider implementations.
• Hybrid signature verification requires both components to be checked.