adcnet

ADCNet - Anonymous Distributed Communication Network

ADCNet is a proof of concept Go implementation of an anonymous distributed communication network using XOR-based message blinding and auction-based message scheduling. It provides anonymous broadcast requiring all servers to participate in message recovery.
The protocol is mostly based on ZIPNet: Low-bandwidth anonymous broadcast from (dis)Trusted Execution Environments.
For an overview of the protocol, see protocol/protocol.md.

[!WARNING] This repository is a work in progress. A lot of it is vibe-coded, a lof of the cryptography is hand-rolled. Do not use for any production use cases! Do use this repository if you want to familiarize yourself with DCNet/ZIPNet and/or experiment with the protocol 💖

Overview

ADCNet enables participants to broadcast messages anonymously. Message sender identity remains hidden as long as one server is honest. The protocol uses an Invertible Bloom Lookup Table (IBLT) based auction system for fair and efficient message scheduling.

Architecture

ADCNet consists of three main components operating in a round-based protocol:

1. Clients

Clients prepare messages for anonymous broadcast by:

• XOR-blinding messages with one-time pads derived from shared secrets with all servers
• Participating in auctions for message slots by encoding bids into IBLT chunks
• Encoding messages at auction-determined offsets if they won slots in previous rounds

2. Aggregators

Aggregators reduce bandwidth requirements by:

• Collecting and verifying client message signatures
• XORing client message vectors together
• Adding client auction vectors in the finite field
• Supporting hierarchical aggregation to further reduce server load

3. Servers

Servers collaborate to reconstruct messages:

• Each server removes its XOR blinding factors from aggregated messages
• All servers must contribute their blinding vectors
• Combined unblinding recovers the original message vector
• The reconstructed IBLT is inverted to determine next round's message scheduling

Key Features

• XOR-Based Blinding: Messages blinded with one-time pads from all server shared secrets
• Anytrust Server Group: Anonymity preserved as long as a single server is honest
• Finite Field Arithmetic: 384-bit field for auction IBLT operations
• IBLT-based Scheduling: Distributed auction mechanism using Invertible Bloom Lookup Tables
• Dynamic Message Sizing: Variable-length messages allocated through auction weights
• TEE Attestation: Optional TDX attestation for service verification

Getting Started

Installation

go get github.com/flashbots/adcnet

Configuration

Services can be configured via YAML files or command-line flags. Config files allow storing credentials securely and simplify deployment.

Example server configuration (server.yaml):

http_addr: ":8081"
registry_url: "http://localhost:8080"
admin_token: "admin:secret"

keys:
  signing_key: ""     # Hex-encoded, generates if empty
  exchange_key: ""    # Hex-encoded, generates if empty

attestation:
  use_tdx: false
  measurements_url: ""

server:
  is_leader: true

Example registry configuration (registry.yaml):

http_addr: ":8080"
admin_token: "admin:secret"

attestation:
  use_tdx: false
  measurements_url: ""

protocol:
  round_duration: 10s
  message_length: 512000
  auction_slots: 10
  min_clients: 1

Running the Demo

The local deployment script runs a complete network using multiservice:

./deploy_local.sh \
  --clients=10 \
  --aggregators=2 \
  --servers=5 \
  --round=10s \
  --msg-length=512000

Use the CLI to interact with the deployed network:

# Send a message
go run ./cmd/demo-cli send -r http://localhost:7999 -m "Hello" -b 100 --skip-verification

# Monitor rounds
go run ./cmd/demo-cli monitor -r http://localhost:7999 --follow --skip-verification

Running Standalone Services

For production deployments, run services independently using the unified service command.

1. Start the Registry

go run ./cmd/registry \
  --addr=:8080 \
  --admin-token="admin:secret" \
  --measurements-url="https://example.com/measurements.json" \
  --round=10s \
  --msg-length=512000

2. Start Servers

# Leader server
go run ./cmd/service \
  --service-type=server \
  --addr=:8081 \
  --registry=http://localhost:8080 \
  --admin-token="admin:secret" \
  --leader

# Additional servers
go run ./cmd/service \
  --service-type=server \
  --addr=:8082 \
  --registry=http://localhost:8080 \
  --admin-token="admin:secret"

3. Start Aggregators

go run ./cmd/service \
  --service-type=aggregator \
  --addr=:8083 \
  --registry=http://localhost:8080 \
  --admin-token="admin:secret"

4. Start Clients

go run ./cmd/service \
  --service-type=client \
  --addr=:8084 \
  --registry=http://localhost:8080

Using Configuration Files

Create a YAML config for each service:

# server.yaml
service_type: "server"
http_addr: ":8081"
registry_url: "http://localhost:8080"
admin_token: "admin:secret"
keys:
  signing_key: ""     # Generated if empty
  exchange_key: ""    # Generated if empty
attestation:
  use_tdx: true
  measurements_url: "https://example.com/measurements.json"
server:
  is_leader: true

go run ./cmd/service --config=server.yaml

TEE Deployment

The unified service command enables building a single binary for TEE VM images:

# Build single binary
go build -o adcnet-service ./cmd/service

# Run with different configurations
./adcnet-service --config=/etc/adcnet/server.yaml
./adcnet-service --config=/etc/adcnet/client.yaml

Enable TDX attestation:

go run ./cmd/service \
  --service-type=server \
  --tdx \
  --tdx-url=http://attestation-service:8080 \
  --registry=http://localhost:8080

Service Registration

All services self-register on startup:

Servers and aggregators include admin_token in their config for authentication.

TDX Attestation

Enable TDX attestation for production deployments:

# In config file:
attestation:
  use_tdx: true
  tdx_remote_url: "http://attestation-service:8080"  # Optional
  measurements_url: "https://example.com/measurements.json"

Or via flags:

go run ./cmd/server \
  --tdx \
  --tdx-url=http://attestation-service:8080 \
  --measurements-url=https://example.com/measurements.json \
  --registry=http://localhost:8080

Basic Usage

import (
    "github.com/flashbots/adcnet/protocol"
)

config := &protocol.ADCNetConfig{
    AuctionSlots:    100,
    MessageLength:   1000,
    MinClients:      3,
    RoundDuration:   10 * time.Second,
}

client := protocol.NewClientService(config, signingKey, exchangeKey)
client.RegisterServer(serverID, serverExchangePubkey)
client.ScheduleMessageForNextRound([]byte("hello"), 10)

Package Structure

protocol

Main protocol implementation including:

• ClientMessager: XOR blinding and message preparation
• ServerMessager: Unblinding and message reconstruction
• AggregatorMessager: Message aggregation operations

blind_auction

Distributed auction mechanism featuring:

• IBLTVector: Multi-level Invertible Bloom Lookup Table implementation
• AuctionEngine: Knapsack-based slot allocation

crypto

Cryptographic primitives providing:

• Field arithmetic in finite fields
• Key management (Ed25519 signing, P-256 key exchange)
• XOR and field-element blinding vector derivation

services

HTTP service implementations with:

• Central registry for service discovery
• TEE attestation verification
• Signed message authentication

cmd

Standalone CLI commands:

• cmd/registry: Central registry service
• cmd/server: ADCNet server
• cmd/aggregator: Message aggregator
• cmd/client: ADCNet client

Security Properties

• Privacy: Message content hidden unless all servers collude
• Anonymity: Sender identity protected through XOR blinding with all servers
• Unlinkability: Fresh blinding prevents correlation between rounds
• Availability: System requires all servers to participate
• Integrity: Digital signatures authenticate all protocol messages
• Attestation: Optional TEE verification for service identity

Implementation Details

• Field Order: 384-bit prime field (48-byte IBLT chunks)
• Message Blinding: XOR with PRF-derived one-time pads unique per server/round
• Auction Blinding: Field addition with server-specific blinding vectors
• IBLT Structure: 4-level filter with 0.75 shrink factor between levels
• Signatures: Ed25519 for all protocol messages
• Key Exchange: ECDH P-256 for shared secret derivation

Testing

go test ./...

Performance benchmarks:

go test -bench=. ./protocol

Security Considerations

• Servers must have pre-established shared secrets with all authorized clients
• All authorized clients should participate (real or dummy messages) for anonymity
• Message padding required to prevent traffic analysis
• Synchronous rounds assumed
• Not all cryptographic operations are constant-time (field arithmetic)
• All servers must be online for message recovery
• Admin credentials should be securely managed in production

License

MIT License - see the LICENSE file for details.