README.md

Acurast Pallet

🚧🚧🚧 The project is still a work in progress 🚧🚧🚧

Introduction

The Acurast Pallet allows a Parachain to integrate the Acurast functionality to be able to securly receive real world data posted by the Acurast Processors.

The Pallet exposes a number of extrinsic.

register

Allows the registration of a job. A registration consists of:

• An ipfs URL to a script (written in Javascript).
  • The script will be run in the Acurast Trusted Virtual Machine that uses a Trusted Execution Environment (TEE) on the Acurast Processor.
• An optional allowedSources list of allowed sources.
  • A list of AccountIds that are allowed to fulfill the job. If no list is provided, all sources are accepted.
• An allowOnlyVerifiedSources boolean indicating if only verified source can fulfill the job.
  • A verified source is one that has provided a valid key attestation.
• An extra structure that can be used to provide custom parameters.

Registrations are saved per AccountId and script, meaning that register is called twice from the same AccountId with the same script value, the previous registration is overwritten.

deregister

Allows the de-registration of a job.

updateAllowedSources

Allows to update the list of allowed sources for a previously registered job.

submitAttestation

Allows an Acurast Processor to submit a key attestation proving its integrity. The extrinsic parameter is a valid attestation certificate chain.

updateCertificateRevocationList

Allows to update the certificate recovation list used during attestation validation.

Setup

Add the following dependency to your Cargo manifest:

[dependencies]
pallet-acurast = { git = "https://github.com/Acurast/acurast-core.git" }

Parachain Integration

Implement pallet_acurast::Config for your Runtime and add the Pallet:

#[derive(RuntimeDebug, Encode, Decode, MaxEncodedLen, TypeInfo, Clone, PartialEq)]
pub struct AcurastRegistrationExtra {
	/// my extra registration parameters
}

pub type MaxAllowedSources = CU32<10>;

parameter_types! {
	pub const AcurastPalletId: PalletId = PalletId(*b"acrstpid");
}

impl pallet_acurast::Config for Runtime {
	type RuntimeEvent = RuntimeEvent;
	type RegistrationExtra = AcurastRegistrationExtra;
	type MaxAllowedSources = MaxAllowedSources;
	type RewardManager = (); // provide proper type to enable rewards to be payed on fulfillment
	type PalletId = AcurastPalletId;
	type RevocationListUpdateBarrier = ();
	type KeyAttestationBarrier = ();
	type UnixTime = pallet_timestamp::Pallet<Self>;
	type WeightInfo = pallet_acurast::weights::WeightInfo<Self>;
}

// Create the runtime by composing the FRAME pallets that were previously configured.
construct_runtime!(
	pub enum Runtime where
		Block = Block,
		NodeBlock = opaque::Block,
		UncheckedExtrinsic = UncheckedExtrinsic,
	{
		// All your other pallets
        ...
		// Acurast
		Acurast: pallet_acurast::{Pallet, Call, Storage, Event<T>} = 50,
	}
);

P256 signatures

Acurast Processors will sign extrinsics (the fulfill call) using a P256 (a.k.a secp256r1) private key.

By default, Substrate does not support the P256 curve. Use the acurast-p256-crypto crate to add support for P256 signature verification.

To do so, use the acurast_p256_crypto::MultiSignature as your parachain Signature type:

use acurast_p256_crypto::MultiSignature;

pub type Signature = MultiSignature;
pub type AccountId = <<Signature as Verify>::Signer as IdentifyAccount>::AccountId;
...

impl frame_system::Config for Runtime {
	type AccountId = AccountId;
    ...
}