LayerZero

Symbiotic-secured DVN (Decentralized Verifier Network) for LayerZero V2 cross-chain messaging.

Overview

The LayerZero provider implements a DVN that uses Symbiotic shared security to verify cross-chain messages. When a message is sent through LayerZero's SendUln302, the DVN contract emits a JobAssigned event. Operators batch these jobs into Merkle trees, collect BLS signatures through Symbiotic relay sidecars, and submit the signed proof to the destination DVN contract. The destination DVN verifies the BLS quorum via the Settlement contract and forwards verification to LayerZero's ReceiveUln302.

Message Flow

Code Pointers

Contracts

• contracts/src/SymbioticLayerZeroDVN.sol -- DVN contract handling assignJob (source) and submitProof (destination)
• contracts/src/symbiotic/Settlement.sol -- BLS signature verification and quorum enforcement
• contracts/src/symbiotic/KeyRegistry.sol -- Operator BLS public key registry
• contracts/src/symbiotic/VotingPowers.sol -- Operator voting power tracking
• contracts/src/symbiotic/Driver.sol -- Epoch and genesis management
• contracts/src/examples/TestOApp.sol -- Test application for sending/receiving messages

Operator (Rust)

• operator/src/provider/layerzero.rs -- Decodes JobAssigned events, stores messages
• operator/src/provider/mod.rs -- Provider trait and registration
• operator/src/crypto/mod.rs -- Merkle tree construction, DVN leaf hashing
• operator/src/signer/mod.rs -- Batches messages, requests BLS signatures
• operator/src/relay_submitter/mod.rs -- Submits signed proofs via OZ Relayer

Config Templates

• config/templates/oz-monitor/monitors/layerzero_job_assigned.json -- Monitor job for JobAssigned events
• config/templates/oz-monitor/triggers/webhook_layerzero.json -- Webhook trigger template

Configuration

Select LayerZero as the active provider:

// config/environments/<env>.json
{
  "activeProvider": "layerzero"
}

Chain config is shared across providers and lives at the top level:

LayerZero predeploys (testnet/mainnet) go in chains.<role>.predeploys.layerzero:

{
  "predeploys": {
    "layerzero": {
      "endpoint": "0x6EDCE65403992e310A62460808c4b910D972f10f",
      "sendUln302": "0xC1868e054425D378095A003EcbA3823a5D0135C9"
    }
  }
}

make deploy and make start use these values to generate runtime configs (destination_chains, chain_relayers, eid_to_chain_id) under generated/<env>/. Validation fails if chain IDs/EIDs drift from the generated deployment state.

Usage

# Select layerzero provider in config/environments/local.json
# "activeProvider": "layerzero"

# Start the stack
make start

# Send a test message
make send MSG="hello"

# Watch until destination verification
make watch

# Or run both in one shot
make e2e

make send sends through TestOApp.send(...) which calls SendUln302, triggering DVN.assignJob().

make watch succeeds when destination target verification is observed on-chain.

See CLI Reference for full command options.

Common Issues

• Message stuck at "Processing" -- BLS signatures not aggregating. Check sidecar health and operator key registration. See Troubleshooting.
• Quorum not reached -- All 3 operators must be running and receiving the same events. See Troubleshooting.
• submitProof reverts -- Check that the OZ Relayer address is authorized as a submitter on the DVN contract, and that Settlement has correct operator keys. See Troubleshooting.