Event Attestator

Note: this repo is currently a work in progress and it will be update in the incoming days

This repository contains the core codebase for the Proofcast event attestation system. This will be useful for anyone aiming at proving that an event or a state change happened on a blockchain to another one, backed by a Trusted Execution Environment attestation.

Currently the TEE supported is Android Strongbox, but other platforms will be integrated soon.

The project is structured like follows:

• common/: low level library providing all the code for block validation and proof generation for each supported blockchain
• apps/: lightweight JSONRPC HTTP server abstracting the interaction to the TEE contained into the device

Architecture

At a glance, the system architecture is better understood from the following diagram:

• The JSONRPC api allows the end user to send commands to the device
• These commands are then sent through the websocket channel to which the device is connects on startup
• The core library deserialize each message coming from the websocket channel and process them accordingly

Setup for EVM chains

1. Copy the configuration sample from sample-config.toml file in the common folder and configure it to your needs, in particular be careful to fill up the [networks.chainName] section with the endpoints property.

2. For each configured chain, set the events array where each element is in the following form:

["<contract-address>","<topic>"]

3. Build the app

cargo build --release --bin jsonrpc-app

4. Run

./jsonrpc-app -c <config.toml>

5. Then follow the README on this repo in order to connect app to the device.

When everything is connected you can manually process a block of interest on the configured chain through the following call:

curl \
  -X POST \
  -H 'Content-Type: application/json' \
  -d '{"jsonrpc":"2.0","id":1,"method":"process","params":["bsc", "38745426", "false", "true"]}' \
  http://127.0.0.1:3030/v1/rpc

The output would contain all the signatures for the configured events in the signed_events array:

{
  "id": 1,
  "jsonrpc": "2.0",
  "result": {
    "latest_block_num": 38745426,
    "network_id": {
      "chain_id": 56,
      "disambiguator": 0,
      "protocol_id": "Ethereum",
      "version": "V1"
    },
    "signed_events": [
      {
        "block_hash": "0x1535c8e9ab42918c2df9d05ba18a816dafc2e3eba45fffc334d2890a2ebcc0bf",
        "encoded_event": "0100016162636465656666200000000000000000000000000000000000000000000000000000000000000000005af3107a4000",
        "event_id": "abcdeeff",
        "log": {
          "address": "0xf5e11df1ebcf78b6b6d26e04ff19cd786a1e81dc",
          "data": [],
          "topics": [
            "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
            "0x000000000000000000000000b0116a2cab9774e9d75834dcce64f99fd75a8579",
            "0x0000000000000000000000000000000000000000000000000000000000000000"
          ]
        },
        "public_key": "03572d2b94ea3918ecd104cdd84a07efc1f9cbc1f11bbd02a6418179894d0d2fc6",
        "signature": "02a893f433fcd688558931a1ab8041c8384ac710550e8ab22c705233c68bd12c38c085405ca6d2c5ea3db8d1b6b84d49f46f070239dcc06aa3c4ec78ea72cb0f01",
        "version": "V1"
      }
    ],
    "timestamp": 1716302631
  }
}