[FEAT] Tamper-Proof Merkle Hash-Chain Compliance & Immutable Audit Log Vault

[jotel-dev]

telegram link : t.me/nullifiersystem

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1. Summary & Core Promise

Financial compliance requires cryptographically immutable event logging. This feature implements a Tamper-Proof Merkle Hash-Chain Audit Vault. Database mutations generate sequential SHA-256 hash chains (hash_n = SHA256(payload + hash_{n-1})). Every 1,000 events, a Merkle tree root is anchored on Stellar via contracts/zk-credential/src/lib.rs, generating verifiable audit inclusion proofs.

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2. Background & Architectural Risks

• Database Tampering: Direct DB access allows rogue admins to alter past trade records without detection.
• Audit Verification: External regulators require cryptographic proof that log records were not altered retroactively.

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3. Database Layer Specifications

Migration SQL (023_add_merkle_audit_vault.sql)

CREATE TABLE audit_hash_chain (
    sequence_id BIGSERIAL PRIMARY KEY,
    event_type VARCHAR(64) NOT NULL,
    payload_hash VARCHAR(64) NOT NULL,
    prev_hash VARCHAR(64) NOT NULL,
    curr_hash VARCHAR(64) NOT NULL,
    created_at TIMESTAMP WITH TIME ZONE DEFAULT CURRENT_TIMESTAMP
);

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4. Backend Route & Service Layer Specifications

Route: GET /api/v1/audit/proof/:eventId

1. Generates Merkle inclusion proof for any past audit event.
2. Returns Stellar anchor transaction hash proving root registration.

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5. Background Processors / Workers

Merkle Anchor Worker (apps/api/src/lib/workers/auditAnchorWorker.ts)

• Aggregates 1,000 log entries into a Merkle tree and commits root on-chain.

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6. Frontend / UI Component Specifications

Component: mobile/frontend/src/pages/AuditorPortal.tsx

• Compliance officer dashboard for searching events, validating SHA-256 chain integrity, and downloading Merkle proof bundles.

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7. Rigor & Test Plan

1. Tamper Detection Test (verify-audit-chain.ts): Mutating a historical row breaks hash continuity.
2. Merkle Inclusion Proof Test (hash-chain.test.ts).

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8. Relevant Files Inventory (18 Files)

• apps/api/src/lib/audit/hash-chain-engine.ts
• apps/api/src/lib/audit/merkle-aggregator.ts
• apps/api/src/lib/audit/proof-generator.ts
• apps/api/src/lib/workers/auditAnchorWorker.ts
• apps/api/src/db/migrations/023_add_merkle_audit_vault.sql
• apps/api/src/routes/audit-vault.ts
• scripts/verify-audit-chain.ts
• apps/api/src/lib/store.ts
• apps/api/src/lib/stellar.ts
• apps/api/src/app.ts
• contracts/zk-credential/src/lib.rs
• mobile/frontend/src/pages/AuditorPortal.tsx
• mobile/frontend/src/components/AuditProofViewer.tsx
• packages/shared/src/types/audit.ts
• packages/shared/src/index.ts
• apps/api/src/lib/audit/__tests__/hash-chain.test.ts
• apps/api/src/routes/__tests__/audit-vault.test.ts
• tests/e2e/audit_tamper_detection.test.ts

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9. Acceptance Criteria

• Sequential SHA-256 hash chains computed for all database mutations.
• CLI verification tool detects single-bit data modifications.

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10. Contributor Notes

• ⚠️ Immutability: NEVER allow sequence number gaps in audit_hash_chain.

[bobo-24]

Hi! I’m a full-stack developer with a strong blockchain background, and I’m confident I can resolve this issue quickly and effectively. I’ll deliver a clean, reliable solution with immediate attention to detail, ensuring it’s completed as soon as possible. Please assign it to me—I’m ready to get started right away.

[Hollujay]

I would like to work on this issue because I will get it done.

[T-kesh]

I’m interested in contributing to this issue.

I’d be particularly interested in working on the backend audit engine, Merkle aggregation, proof generation, and verification tests. I’ll also pay close attention to maintaining strict sequence continuity and ensuring that any historical database tampering is reliably detected.

[grantfox-oss]

🦊 GrantFox — @T-kesh has been assigned to this issue as part of the Third Campaign campaign!

Next steps:

1. Open a Pull Request referencing this issue (e.g., Closes #405)
2. Your PR will be reviewed by the Nullifier-Systems maintainers

Good luck! Track your progress on GrantFox.