BlindVault

BlindVault is a privacy-preserving credential issuance and redemption service built on BLS12-381 blind signatures and DLEQ proofs.

Purpose

BlindVault enables clients to request unbiased blind credentials, verify that the server signed them with a derived public key, and consume them without revealing the underlying secret material.

Features

• Blind credential issuance using BLS12-381 blind signatures
• DLEQ proof of correct signing key usage
• Epoch and credential class key derivation from a single master seed
• Replay protection using deterministic nullifiers
• Redis-backed nullifier store for production
• JWT-protected issuance endpoint
• Health endpoint for readiness checks

Quickstart

1. Create configs/config.yaml or set environment variables.
2. Run the server:

go run ./cmd/server/main.go --config configs/config.yaml

3. Validate health:

curl http://localhost:8080/health

Documentation

• docs/api_reference.md — API endpoints, request and response formats, and errors
• docs/client_reference.md — Go client library and CLI usage
• docs/deployment_guide.md — deployment, Docker Compose, Redis setup, and health checks
• docs/crypto_spec.md — cryptographic specification, DLEQ proof details, and security assumptions
• docs/crypto_vectors.md — generated test vector placeholder
• CONTRIBUTING.md — contribution process and testing guidelines

Client package and CLI

BlindVault includes a high-level Go client wrapper in pkg/client and a command-line interface in cmd/bv.

Build the CLI:

go build -o bv ./cmd/bv

Examples:

bv blind --message "hello" --server http://localhost:8080
bv unblind --signature <blind_signature_hex> --id <request_id>
bv redeem --signature <unblinded_signature_hex> --witness <witness_hex> --class tier_gold --epoch 2026-01

The blind command returns JSON with blinded, witness, and request_id. The verify command validates a DLEQ proof locally, unblind converts a blind signature into an unblinded one using the stored request state, and redeem submits the credential to /v1/credential/consume.

Client state is persisted to ~/.blindvault/state.json.

Running tests

go test ./...
go test -v ./pkg/crypto

Generating crypto vectors

go run scripts/generate_vectors.go --output docs/crypto_vectors.md

Configuration

You can override config values with environment variables:

• MASTER_SEED_HEX
• ACTIVE_EPOCH
• SUPPORTED_EPOCHS
• DST
• AUTH_SECRET
• REDIS_ADDR
• REDIS_PASSWORD
• REDIS_DB
• USE_MEMORY_STORE
• LISTEN_ADDR

Notes

Use use_memory_store: true only for testing. Production deployment should use Redis and protect MASTER_SEED_HEX and AUTH_SECRET with a secrets manager.