CDCavell.AsiBackbone.Signing.LocalDevelopment 1.2.1

CDCavell.AsiBackbone.Signing.LocalDevelopment

CDCavell.AsiBackbone.Signing.LocalDevelopment provides a local-development RSA signing and verification provider for exercising AsiBackbone signing abstractions without Azure Key Vault, HSM, cloud KMS, certificate-store, or external infrastructure dependencies.

New to AsiBackbone? Start with the concept, not this package: Intent to Execution: An Accountability Pattern and the documentation site. This README covers one package in the family.

Important: This package is intended for local development, samples, and tests. It is not a production managed-key provider and does not provide tamper-evidence, immutability, legal non-repudiation, compliance certification, or protected key custody by itself.

Boundary

This package implements:

• IAsiBackboneSigningService
• IAsiBackboneSignatureVerificationService

It signs the SigningRequest.SigningHash value using an in-process RSA key generated for the service instance and returns provider-neutral SigningMetadata.

Core remains provider-neutral. CDCavell.AsiBackbone.Core does not reference this package.

Metadata returned

Successful signing results include:

• signing hash
• hash algorithm
• Base64 signature value
• signature algorithm descriptor
• key ID
• key version
• provider descriptor
• signed UTC timestamp
• local-development warning metadata

Signing failures in normal flow return unsigned signing metadata with explicit signing_status, failure_code, and failure_message values unless the host opts out by setting ReturnUnsignedOnFailure = false.

Example registration

var localSigningOptions = LocalDevelopmentSigningOptions.Create(
    keyId: "sample-local-dev-key",
    keyVersion: "dev");

var localSigningService = new LocalDevelopmentSigningService(localSigningOptions);

builder.Services.AddSingleton(localSigningService);
builder.Services.AddSingleton<IAsiBackboneSigningService>(localSigningService);
builder.Services.AddSingleton<IAsiBackboneSignatureVerificationService>(localSigningService);

Example flow

AuditLedgerRecord
  -> CanonicalPayloadBuilder.ForAuditLedgerRecord(...)
  -> CanonicalPayloadHasher.ComputeHash(...)
  -> SigningRequest
  -> LocalDevelopmentSigningService.SignAsync(...)
  -> SignatureVerificationRequest
  -> LocalDevelopmentSigningService.VerifyAsync(...)

Non-goals

This package does not:

• integrate with Azure Key Vault, Managed HSM, local machine certificate stores, or cloud KMS services;
• persist private key material;
• provide production key rotation;
• provide legal non-repudiation;
• verify an audit hash chain;
• provide immutable storage or external anchoring;
• make unsigned, signed, or verified records tamper-evident by default.

Use a managed-key or HSM-backed provider for production workflows where signing is part of a security or audit-control boundary.