Phala Cloud Documentation — Confidential AI on TEE

Overview

The Trust Center is an open-source verification platform that automates the validation of TEE attestations for dstack-based applications. It performs multi-dimensional verification across hardware, operating system, source code, and domain ownership to provide cryptographic proof of deployment integrity. Architecture: Monorepo with TypeScript verifier library, background worker queue, and web dashboard. Repository: https://github.com/Phala-Network/trust-center

System Architecture

Components

Verifier Package (@phala/dstack-verifier)
- Core TypeScript library for attestation verification
- Modular verifier classes with configurable flags
- Supports Intel TDX quote validation
- Platform-specific verifiers (PhalaCloud, Redpill.ai)
Background Worker
- Built on BullMQ for reliable job processing
- PostgreSQL for task persistence
- Redis for queue management
- Asynchronous verification execution
Web Application
- Next.js dashboard for report visualization
- Direct database access for read operations
- Real-time verification status updates
- Public report URLs for transparency
Storage Layer
- PostgreSQL: Verification tasks and results
- Redis: Job queue state
- S3-compatible: Raw attestation data and quotes

Verification Phases

The Trust Center performs verification in four distinct phases:

Phase 1: Hardware Attestation

Validates the TEE quote to prove execution on genuine Intel hardware. What’s verified:

Quote signature: ECDSA-P256 signature validation using Intel certificates
Certificate chain: Validates back to Intel root CA
TCB status: Checks Trusted Computing Base security version
Platform identity: Confirms genuine Intel TDX processor
Revocation status: Verifies no certificates or platforms are revoked

Tools used:

Quote verification with DCAP-QVL

Implementation:

// Note: verifyQuote is an internal utility in @phala/dstack-verifier
// For hardware verification, use VerificationService with hardware flag
import { VerificationService } from '@phala/dstack-verifier';

const service = new VerificationService();

// For Redpill apps (with GPU models)
const result = await service.verify({
  contractAddress: '0x...',
  model: 'phala/llama-3.1-8b'
}, {
  hardware: true,
  os: false,
  sourceCode: false
});

// Or for Phala Cloud apps
const result2 = await service.verify({
  contractAddress: '0x...',
  domain: 'myapp.phala.network'
}, {
  hardware: true,
  os: false,
  sourceCode: false
});

console.log('Hardware verified:', result.success);

Failure modes:

Invalid signature: Quote not signed by genuine TEE
Revoked certificates: Platform or attestation key compromised
Outdated TCB: Security patches not applied

Phase 2: Operating System Integrity

Confirms the OS image matches a known trusted dstack version. What’s verified:

MRTD: Measurement Root of Trust Domain (TD initial state)
RTMR0: Virtual hardware environment
RTMR1: Linux kernel measurement
RTMR2: Kernel command line and initrd

Tools used:

dstack image verification with dstack-mr-cli

Measurement calculation:

# Calculate OS measurements using dstack-mr-cli
dstack-mr-cli --kernel bzImage --initrd initrd.img --cmdline "console=htyS0"

# Output: MRTD, RTMR0, RTMR1, RTMR2 values

Verification logic:

// OS verification is performed by VerificationService
// The service automatically downloads trusted dstack images and compares measurements
import { VerificationService } from '@phala/dstack-verifier';

const service = new VerificationService();

const result = await service.verify({
  contractAddress: '0x...',
  model: 'phala/llama-3.1-8b',  // For Redpill
  // OR domain: 'myapp.phala.network'  // For Phala Cloud
  metadata: {
    osSource: {
      github_repo: 'https://github.com/Dstack-TEE/meta-dstack',
      git_commit: 'abc123',
      version: 'v0.5.2'
    }
  }
}, {
  hardware: false,
  os: true,  // Enable OS verification
  sourceCode: false
});

console.log('OS verified:', result.success);

Why it matters: Ensures the OS hasn’t been modified, backdoored, or replaced with an untrusted image.

Phase 3: Source Code Verification

Validates the application code matches the deployed version. What’s verified:

compose-hash: SHA256 hash of docker-compose.yaml
app-id: Application identifier (used for key derivation)
instance-id: Specific deployment instance
key-provider: KMS service address
RTMR3: Application measurement register containing above values

RTMR3 structure:

interface RTMR3Events {
  'app-id': string;           // Application identifier
  'compose-hash': string;     // SHA256 of docker-compose.yaml
  'instance-id': string;      // Deployment instance UUID
  'key-provider': string;     // KMS endpoint URL
}

RTMR3 calculation:

// RTMR3 is computed as a hash chain of events
function computeRTMR3(events: RTMR3Events): string {
  let rtmr3 = '0'.repeat(96); // Initial value (all zeros)

  for (const [key, value] of Object.entries(events)) {
    const event = JSON.stringify({ [key]: value });
    const eventHash = sha384(event);
    rtmr3 = sha384(rtmr3 + eventHash);
  }

  return rtmr3;
}

Verification against blockchain:

import { createPublicClient, http } from 'viem';
import { mainnet } from 'viem/chains';

const client = createPublicClient({
  chain: mainnet,
  transport: http()
});

// Read compose-hash from blockchain registry
const onChainHash = await client.readContract({
  address: '0x...',
  abi: registryABI,
  functionName: 'getAppComposeHash',
  args: [appId]
});

const match = onChainHash === quote.body.rtmr3.composeHash;
console.log('Source code verified:', match);

Tools:

dstack attestation docs

Phase 4: Domain Verification (Gateway Only)

For applications with custom domains, verifies zero-trust HTTPS. What’s verified:

TLS certificate: Private key generated in TEE
CAA records: DNS locked to TEE-controlled Let’s Encrypt account
Certificate Transparency: All certs logged to public CT logs
Domain control: Cryptographic proof of domain ownership

Verification process:

Extract TLS public key from reportData field
Query Certificate Transparency logs (via crt.sh)
Verify all certificates for domain match the TEE public key
Check CAA records point to TEE Let’s Encrypt account
Confirm no unauthorized certificates exist

CAA record format:

example.com CAA 0 issue "letsencrypt.org;validationmethods=dns-01;accounturi=https://acme-v02.api.letsencrypt.org/acme/acct/XXXXXX"

CT Log monitoring:

// Domain verification (including CT logs) is performed by VerificationService
// The service checks Certificate Transparency logs when ctLog flag is enabled
import { VerificationService } from '@phala/dstack-verifier';

const service = new VerificationService();

const result = await service.verify({
  contractAddress: '0x...',
  domain: 'example.com'
}, {
  hardware: false,
  os: false,
  sourceCode: false,
  teeControlledKey: true,    // Verify TEE controls TLS private key
  certificateKey: true,      // Verify certificate matches
  dnsCAA: true,              // Verify DNS CAA records
  ctLog: true                // Check Certificate Transparency logs (can be slow)
});

if (!result.success) {
  console.error('❌ Domain verification failed:', result.errors);
}

Why it matters: Traditional cloud providers can intercept HTTPS traffic because they control certificate private keys. Zero-trust HTTPS proves even the cloud provider cannot decrypt your traffic.

Using the Verifier Package

Basic Usage

import { VerificationService } from '@phala/dstack-verifier';

const service = new VerificationService();

// For Redpill AI models
const result = await service.verify({
  contractAddress: '0x7e0817205044eb202a590a0d236ccb4d66140197',
  model: 'phala/llama-3.1-8b',
  metadata: {
    osSource: {
      github_repo: 'https://github.com/Dstack-TEE/meta-dstack',
      git_commit: 'abc123',
      version: 'v0.5.2'
    }
  }
}, {
  hardware: true,      // Verify Intel TDX quote
  os: true,            // Verify OS integrity
  sourceCode: true,    // Verify compose-hash
  teeControlledKey: false,
  certificateKey: false,
  dnsCAA: false,
  ctLog: false
});

// For Phala Cloud apps with custom domains
const result2 = await service.verify({
  contractAddress: '0x...',
  domain: 'myapp.phala.network'
}, {
  hardware: true,
  os: true,
  sourceCode: true,
  teeControlledKey: true,  // Verify TEE controls TLS key
  certificateKey: true,    // Verify certificate
  dnsCAA: false,           // Skip DNS CAA check (can be slow)
  ctLog: false             // Skip CT log check (can be very slow)
});

console.log('Verification success:', result.success);
console.log('Verification errors:', result.errors);
console.log('Data objects:', result.dataObjects);

Configurable Verification Flags

import type { VerificationFlags } from '@phala/dstack-verifier';

// Available verification flags (all optional, defaults shown)
const flags: VerificationFlags = {
  hardware: true,           // Verify Intel TDX quote
  os: true,                 // Verify OS integrity (MRTD, RTMR0-2)
  sourceCode: true,         // Verify source code (compose-hash in RTMR3)
  teeControlledKey: true,   // Verify TEE controls private key
  certificateKey: true,     // Verify certificate matches attestation
  dnsCAA: true,             // Verify DNS CAA records (can be slow)
  ctLog: false              // Verify Certificate Transparency logs (can be very slow)
};

// Use with VerificationService
const service = new VerificationService();
const result = await service.verify(config, flags);

Platform-Specific Configuration

import { VerificationService } from '@phala/dstack-verifier';
import type { PhalaCloudConfig, RedpillConfig } from '@phala/dstack-verifier';

const service = new VerificationService();

// Phala Cloud configuration
const phalaConfig: PhalaCloudConfig = {
  contractAddress: '0x...',
  domain: 'myapp.phala.network',
  metadata: {
    osSource: {
      github_repo: 'https://github.com/Dstack-TEE/meta-dstack',
      git_commit: 'abc123',
      version: 'v0.5.2'
    }
  }
};

// Redpill.ai configuration
const redpillConfig: RedpillConfig = {
  contractAddress: '0x...',
  model: 'phala/llama-3.1-8b',
  metadata: {
    osSource: {
      github_repo: 'https://github.com/Dstack-TEE/meta-dstack',
      git_commit: 'def456',
      version: 'v0.5.3'
    }
  }
};

// Use the same service for both platforms
const phalaResult = await service.verify(phalaConfig);
const redpillResult = await service.verify(redpillConfig);

Error Handling

import { VerificationService } from '@phala/dstack-verifier';
import type { VerificationError } from '@phala/dstack-verifier';

const service = new VerificationService();

try {
  const result = await service.verify(config, flags);

  if (!result.success) {
    console.error('Verification failed');

    // Errors are objects with { message: string }
    for (const error of result.errors) {
      console.error('Error:', error.message);

      // Check error messages for specific issues
      if (error.message.includes('signature')) {
        console.error('→ Hardware signature invalid - not genuine TEE');
      } else if (error.message.includes('compose')) {
        console.error('→ Deployed code does not match source');
      } else if (error.message.includes('MRTD') || error.message.includes('RTMR')) {
        console.error('→ OS measurements do not match trusted version');
      }
    }
  } else {
    console.log('✓ All verification checks passed');
    console.log('Data objects:', result.dataObjects);
  }
} catch (err) {
  // Handle unexpected errors during verification
  console.error('Verification process error:', err);
}

Self-Hosting Trust Center

Organizations can run their own Trust Center instance for private verification.

Prerequisites

Node.js 18+ / Bun
PostgreSQL 14+
Redis 6+
S3-compatible storage (MinIO, AWS S3, etc.)

Setup

# Clone repository
git clone https://github.com/Phala-Network/trust-center.git
cd trust-center

# Install dependencies
bun install

# Configure environment
cp .env.example .env
# Edit .env with your database, redis, and S3 credentials

# Run database migrations
bun run db:migrate

# Start services
bun run worker    # Background verification worker
bun run webapp    # Web dashboard (localhost:3000)

Configuration

.env file:

# Database
DATABASE_URL=postgresql://user:pass@localhost:5432/trust_center

# Redis
REDIS_URL=redis://localhost:6379

# S3 Storage
S3_ENDPOINT=https://s3.amazonaws.com
S3_BUCKET=trust-center-quotes
S3_ACCESS_KEY=...
S3_SECRET_KEY=...

# PCCS (for quote verification)
PCCS_URL=https://pccs.phala.network/sgx/certification/v4/

# Optional: Blockchain RPC for source code verification
ETH_RPC_URL=https://eth-mainnet.g.alchemy.com/v2/...

Docker Deployment

version: '3.8'
services:
  postgres:
    image: postgres:14
    environment:
      POSTGRES_DB: trust_center
      POSTGRES_USER: trust_center
      POSTGRES_PASSWORD: secure_password
    volumes:
      - postgres_data:/var/lib/postgresql/data

  redis:
    image: redis:6
    volumes:
      - redis_data:/data

  worker:
    build: .
    command: bun run worker
    depends_on:
      - postgres
      - redis
    env_file: .env

  webapp:
    build: .
    command: bun run webapp
    ports:
      - "3000:3000"
    depends_on:
      - postgres
    env_file: .env

volumes:
  postgres_data:
  redis_data:

Next Steps

User Documentation: Trust Center Verification Reports
Attestation Basics: Understanding TEE Attestation
API Reference: Attestation API
dstack SDK: Getting Started with dstack

Additional Resources

GitHub Repository: trust-center
DeepWiki Analysis: Technical Deep Dive
Live Platform: trust.phala.com
dstack Attestation Docs: attestation.md

Design Documents

Trust Center Technical Documentation

Overview

System Architecture

Components

Verification Phases

Phase 1: Hardware Attestation

Phase 2: Operating System Integrity

Phase 3: Source Code Verification

Phase 4: Domain Verification (Gateway Only)

Using the Verifier Package

Basic Usage

Configurable Verification Flags

Platform-Specific Configuration

Error Handling

Self-Hosting Trust Center

Prerequisites

Setup

Configuration

Docker Deployment

Next Steps

Additional Resources

Design Documents

Documentation Index

​Overview

​System Architecture

​Components

​Verification Phases

​Phase 1: Hardware Attestation

​Phase 2: Operating System Integrity

​Phase 3: Source Code Verification

​Phase 4: Domain Verification (Gateway Only)

​Using the Verifier Package

​Basic Usage

​Configurable Verification Flags

​Platform-Specific Configuration

​Error Handling

​Self-Hosting Trust Center

​Prerequisites

​Setup

​Configuration

​Docker Deployment

​Next Steps

​Additional Resources

Overview

System Architecture

Components

Verification Phases

Phase 1: Hardware Attestation

Phase 2: Operating System Integrity

Phase 3: Source Code Verification

Phase 4: Domain Verification (Gateway Only)

Using the Verifier Package

Basic Usage

Configurable Verification Flags

Platform-Specific Configuration

Error Handling

Self-Hosting Trust Center

Prerequisites

Setup

Configuration

Docker Deployment

Next Steps

Additional Resources