Claiming A Chip

This section details how to claim a chip using the ers-scripts repo.

Set Up

If you are trying to execute a transaction it is assumed that you have also read the Set Up section. If you are just looking for an example read on

To be able to claim a chip you first need to specify the Ethereum account you want to call claimChip, note that this address will be set as the "owner" of the chip however that can be changed post-creation. To do this, you must input the private key of the account you wish to use into the .env file. The .env file should look something like this:

...
GOERLI_CHIP_OWNER_PRIVATE_KEY=ac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80
...
MAINNET_CHIP_OWNER_PRIVATE_KEY=ac0974bec39a17e36ba4a6b4d238ff944bacb478cbed5efcae784d7bf4f2ff80

Replace the stand-in private keys (pulled from Hardhat) with the private key you wish to use. Make sure that you are using the correct private key for the network you are deploying to.

Defining Script Inputs

The inputs to the claim chip script are more complex than simply inputting on a command line can allow. To get around this we use a JSON file to define the inputs to the script. The params file is located at task_params/claimChip.json and it should look something like this:

{
    "name": "",
    "chipClaimDataLocation": "",
    "manufacturerValidationLocation": ""
}

If the file does not exist yet you can create it by calling: cp task_params/claimChip.default.json task_params/claimChip.json

To fields in the file are defined as such:

• name: ERS name for the chip
• chipClaimDataLocation: Either local location of chip's claim data file or an IPFS folder containing the ProjectEnrollmentIPFS information for chips in the project
• manufacturerValidationLocation: Either local location of manufacturer validation file or an IPFS folder containing the ManufacturerValidation information for chips in the project

The chipClaimData has the following definition:

export interface ProjectEnrollmentIPFS {
  projectRegistrar: Address,
  enrollmentId: string,
  TSMMerkleInfo: TSMMerkleProofInfo,
  tsmCertificate: string,
  custodyProof: string
}

Executing the Script

The script to claim a chip is located in tasks/projectCreation.ts. To execute the script run:

yarn claimChip --network [network]

When the script is run the first step is to scan the chip being claimed using our gateway utility:

export async function getChipPublicKeys(gate: any): Promise<[Address, Address]> {
  let cmd = {
    "name": "get_pkeys",
  };
 
  const rawKeys = (await gate.execHaloCmd(cmd)).output;
 
  return [rawKeys.etherAddresses['1'], rawKeys.etherAddresses['2']];
}

We then call out to get the chipClaimData and manufacturerValidation from there respective locations. After that we create a chipOwnershipProof that ties the msg.sender of the transaction to the chip being claimed:

    const chainId = BigNumber.from(await hre.getChainId());
    const commitBlock = BigNumber.from(await hre.ethers.provider.getBlockNumber());
    const nameHash = calculateLabelHash(params.name);
 
    const packedMsg = ethers.utils.solidityPack(["uint256", "uint256", "bytes32", "address"], [chainId,commitBlock, nameHash, chipOwner]);
 
    const chipOwnershipProof = (await getChipSigWithGateway(gate, packedMsg)).signature.ether;

Note that we also calculate the nameHash of the chip being claimed, which is an ENS compliant hash of the name passed in the params file.

Finally, we pass everything from above to the ProjectRegistrar to claim the chip:

    await rawTx({
      from: chipOwner,
      to: projectRegistrar.address,
      data: projectRegistrar.interface.encodeFunctionData(
        "claimChip",
        [
          chipId,
          nameHash,
          chipIdClaimInfo.TSMMerkleInfo,
          chipIdManufacturerInfo.validationInfo,
          commitBlock,
          chipOwnershipProof,
          chipIdClaimInfo.tsmCertificate,
          chipIdClaimInfo.custodyProof
        ]
      )
    });