Protocol Deep Dive

The Priv protocol consists of four interconnected Solana programs built on the Anchor framework, designed to enable private payments and escrow functionality. All programs are deployed on devnet and work together to provide a comprehensive stealth payment system.

Program Overview

Core Programs

Architecture Overview

Stealth Payment Flow

1. Meta-Address Registration: Users register their stealth meta-addresses (spend + view keys) via Ghost Registry
2. Payment Creation: Senders create escrow payments using one of the three escrow programs
3. Stealth Announcement: Ghost Registry creates on-chain announcements for stealth payments
4. Claim Process: Recipients use claim secrets to unlock escrowed funds

Domain-Separated Claim Hashing

All escrow programs use the same claim hash verification system:

let domain = b"priv_claim";
let computed_hash = hashv(&[domain, &claim_secret]);
require!(computed_hash.to_bytes() == escrow.claim_hash);

This ensures claim secrets are domain-separated and cannot be reused across different contexts.

Program Interactions

Ghost Registry ↔ Escrow Programs

• Ghost Registry handles meta-address management and stealth payment announcements
• Escrow Programs handle the actual token custody and claim verification
• Both systems work independently but are designed to complement each other

Token Interface Compatibility

All programs use SPL Token-2022 compatible interfaces via Anchor's token_interface, ensuring compatibility with:

• SPL Token (legacy)
• SPL Token-2022
• Token Extensions

Fee Structure

• Payment Escrow: Configurable fee (basis points) set by protocol admin
• Multisig Escrow: Uses same configurable fee system as Payment Escrow
• Conditional Escrow: Fixed 2.5% fee (250 basis points) hardcoded per milestone

Security Features

PDA-Based Authority

All programs use Program Derived Addresses (PDAs) for secure account management:

• Deterministic account addresses
• Program-controlled signing authority
• Prevents unauthorized access

Expiry Protection

All escrow types include expiry timestamps:

• Prevents indefinite token lockup
• Allows refunds after expiration
• Protects both creators and recipients

Access Controls

• Owner-only operations: Meta-address updates, escrow refunds
• Approver verification: Multisig escrow approval tracking
• Creator authorization: Milestone release permissions

Account Structure

All accounts use Anchor's 8-byte discriminator prefix for type safety and include bump seeds for PDA verification. See the Account Structures page for detailed byte layouts.

Error Handling

Each program defines comprehensive error codes for all failure scenarios. See the Error Codes page for the complete reference.

Next Steps

Explore the individual program documentation:

• Ghost Registry - Meta-address and announcement management
• Payment Escrow - Simple hash-locked payments
• Multisig Escrow - Multi-signature approval system
• Conditional Escrow - Milestone-based payments