2 stable releases
9.0.1 | Oct 20, 2022 |
---|---|
8.0.0 | Jun 23, 2022 |
#25 in #filecoin-actors
Used in test_vm
1MB
23K
SLoC
Built-in Filecoin actors
This repo contains the code for the on-chain built-in actors that power the Filecoin network starting from network version 16, epoch 1960320 on 2022-07-06.
These actors are written in Rust and are designed to operate inside the Filecoin Virtual Machine. A reference implementation of the latter exists at filecoin-project/ref-fvm.
The build process of this repo compiles every actor into Wasm bytecode and generates an aggregate bundle to be imported by all clients. The structure of this bundle is standardized. Read below for details.
This codebase was canonicalized in FIP-0031. As a result, this actor implementation is the only one recognized by the network from network version 16 onwards.
Pre-FVM actors
Actors for the following network versions prior to nv16 are implemented here as well:
- nv14 actors to facilitate testing.
- nv15 actors to enable the nv15=>nv16 upgrade.
Importable bundle
The main output of this repo is a CARv1 archive bundling all Wasm bytecode for all actors into a single file, with the following characteristics:
- The CARv1 header points to a single root CID.
- The root CID resolves to a DAG-CBOR
encoded block defining a
Manifest
type (defined below) containing a version number for the bundle format (currently always1
) and a CID for aManifestPayload
. - The
ManifestPayload
(defined below) is contained within a DAG-CBOR encoded block and defines a type that associates actor type names with their corresponding CIDs. - The CIDs for all actors are contained within the same CARv1 archive as compiled Wasm bytecode contained within RAW blocks.
Manifest schema
# Manifest is encoded as: [version, CID]
type Manifest struct {
version Int
payload &ManifestPayload
} representation tuple
# ManifestPayload is encoded as: [ ["actorkey", CID], ["actorkey", CID], ... ]
#
# It alternatively may be interpreted as:
# type ManifestPayload {String : &ActorBytecode} representation listpairs
# Or simply as a list of tuples.
type ManifestPayload struct {
system &ActorBytecode
init &ActorBytecode
cron &ActorBytecode
account &ActorBytecode
storagepower &ActorBytecode
storageminer &ActorBytecode
storagemarket &ActorBytecode
paymentchannel &ActorBytecode
multisig &ActorBytecode
reward &ActorBytecode
verifiedregistry &ActorBytecode
datacap &ActorBytecode
placeholder &ActorBytecode
evm &ActorBytecode
eam &ActorBytecode
ethaccount &ActorBytecode
} representation listpairs
# RAW block
type ActorBytecode bytes
Precompiled actor bundles are provided as release binaries in this repo. The
fil_builtin_actors_bundle
crate on
crates.io will not be updated.
Releasing
We release all actors, the runtime, and the state abstraction at the same time by:
- Changing the
workspace.package.version
in the top-levelCargo.toml
file. - Creating a release in GitHub.
This will trigger an automatic bundle-build by GitHub CI, and the generated bundles will be attached to the GitHub release.
Instructions for client implementations
Obtaining an actors bundle
There are two options:
- Building from source.
- Downloading the precompiled release bundle from GitHub.
Instructions to build from source (option 1):
- Clone the repo.
- Check out the relevant branch or tag (see Versioning section below).
make bundle
from the workspace root.
The bundle be written to output/builtin-actors.car
.
Both options are compatible with automation via scripts or CI pipelines.
Integrating an actors bundle
This part is implementation-specific. Options include:
- Embedding the bundle's CARv1 bytes into the distribution's binary.
- Downloading CARv1 files on start (with some form of checksumming for added security).
Loading and using the actors bundle with ref-fvm
Once the implementation has validated the authenticity of the bundle, it is expected to do the following:
- Import the CARv1 into the blockstore.
- Retain the root CID in memory, indexed by network version.
- Feed the root CID to ref-fvm's Machine constructor, to tell ref-fvm which CodeCID maps to which built-in actor.
Multiple network version support
Because every network version may be backed by different actor code, implementations should be ready to load multiple actor bundles and index them by network version.
When instantiating the ref-fvm Machine, both the network version and the corresponding Manifest root CID must be passed.
Versioning
A fair question is how crate versioning relates to the protocol concept of
ActorVersion
. We adopt a policy similar to specs-actors:
- Major number in crate version correlates with
ActorVersion
. - We generally don't use minor versions; these are always set to
0
. - We strive for round major crate versions to denote the definitive release for a given network upgrade. However, due to the inability to predict certain aspects of software engineering, this is not a hard rule and further releases may be made by bumping the patch number.
Development versions will use qualifiers such as -rc (release candidate).
As an example of application of this policy to a v10 actor version lineage:
- Unstable development versions are referenced by commit hash.
- Stable development versions are tagged as release candidates: 10.0.0-rc1, 10.0.0-rc2, etc.
- Definitive release: 10.0.0.
- Patched definitive release: 10.0.1.
- Patched definitive release: 10.0.2.
- Network upgrade goes live with 10.0.2.
About this codebase
Relation to specs-actors
This repo supersedes specs-actors, and fulfils two roles:
- executable specification of built-in actors.
- canonical, portable implementation of built-in actors.
Credits
This codebase was originally forked from the actors v6 implementation of the Forest client, and was adapted to the FVM environment.
Community
Because this codebase is a common good across all Filecoin client implementations, it serves as a convergence area for all Core Devs regardless of the implementation or project they identify with.
License
Dual-licensed: MIT, Apache Software License v2, by way of the Permissive License Stack.
Except the EVM precompile test data, which is licensed under the LGPL v3 and not included in crates or build artifacts.
Dependencies
~11MB
~193K SLoC