Filecoin FFI

C and CGO bindings for Filecoin's Rust libraries, i.e: proofs and ref-fvm. This repository is built to enable the reference implementation of Filecoin, Lotus, to consume the Rust libraries that are needed.

Building

To build and install libfilcrypto, its header file and pkg-config manifest, run:

make

To optionally authenticate with GitHub for assets download (to increase API limits) set GITHUB_TOKEN to personal access token.

If no precompiled static library is available for your operating system, the build tooling will attempt to compile a static library from local Rust sources.

Installation notes

By default, building this will download a pre-built binary of the ffi. The advantages for downloading it are faster build times, and not requiring a rust toolchain and build environment.

The disadvantage to downloading the pre-built binary is that it will not be optimized for your specific hardware. This means that if raw performance is of utmost importance to you, it's highly recommended that you build from source.

Building from Source

To opt out of downloading precompiled assets, set FFI_BUILD_FROM_SOURCE=1:

To allow portable building of the blst dependency, set FFI_USE_BLST_PORTABLE=1:

rm .install-filcrypto \
    ; make clean \
    ; FFI_BUILD_FROM_SOURCE=1 FFI_USE_BLST_PORTABLE=1 make

By default, a 'gpu' option is used in the proofs library. This feature is also used in FFI unless explicitly disabled. To disable building with the 'gpu' dependency, set FFI_USE_GPU=0:

rm .install-filcrypto \
    ; make clean \
    ; FFI_BUILD_FROM_SOURCE=1 FFI_USE_GPU=0 make

GPU support

CUDA for GPU support is now enabled by default in the proofs library. This feature can optionally be replaced by OpenCL by using FFI_USE_OPENCL=1 set in the environment when building from source. Alternatively, if the CUDA toolkit (such as nvcc) cannot be located in the environment, OpenCL support is used instead. To disable GPU support entirely, set FFI_USE_GPU=0 in the environment when building from source.

There is experimental support for faster C2 named "SupraSeal". To enable it, set FFI_USE_CUDA_SUPRASEAL=1. It's specific to CUDA and won't work with OpenCL.

rm .install-filcrypto \
    ; make clean \
    ; FFI_BUILD_FROM_SOURCE=1 make

By default, a 'multicore-sdr' option is used in the proofs library. This feature is also used in FFI unless explicitly disabled. To disable building with the 'multicore-sdr' dependency, set FFI_USE_MULTICORE_SDR=0:

rm .install-filcrypto \
    ; make clean \
    ; FFI_BUILD_FROM_SOURCE=1 FFI_USE_MULTICORE_SDR=0 make

Updating rust-fil-proofs (via rust-filecoin-proofs-api)

If rust-fil-proofs has changed from commit X to Y and you wish to get Y into the filecoin-ffi project, you need to do a few things:

1. Update the rust-filecoin-proofs-api Cargo.toml file to point to Y
2. Run cd rust && cargo update -p "filecoin-proofs-api" from the root of the filecoin-ffi project
3. After the previous step alters your Cargo.lock file, commit and push

go get

go get needs some additional steps in order to work as expected.

Get the source, add this repo as a submodule to your repo, build it and point to it:

$ go get github.com/filecoin-project/filecoin-ffi
$ git submodule add https://github.com/filecoin-project/filecoin-ffi.git extern/filecoin-ffi
$ make -C extern/filecoin-ffi
$ go mod edit -replace=github.com/filecoin-project/filecoin-ffi=./extern/filecoin-ffi

Updating the Changelog

The mkreleaselog script (in the project root) can be used to generate a good portion of the filecoin-ffi changelog. For historical reasons, the script must be run from the root of a filecoin-ffi checkout which is in your $GOPATH.

Run it like so:

./mkreleaselog v0.25.0 v0.26.0 > /tmp/v0.26.0.notes.txt

Contribution

Maintainers

The core maintainers of this repository are:

• @nemo & @vmx, from the fil-crypto team
• @lotus-maintainers
• @stebalien, from the FVM team

Maintainers are not only the contributors of this repository, but also exercise a range of editorial responsibilities to keep the repository organized for the OSS contributors, that includes triage the issues, review and merge/close PRs, publish releases and so on.

Development Guidelines (WIP)

CI Builds

To start a CI job to build binaries off of a commit push a tag starting with the character v, i.e. v1.22.0-rc2.

Branches

master is considered as the development branch of this repository. Changes being introduced to master must be tested (programmable and/or manual). The head of the master will be tagged and released upon the merge of each PR automatically.

We will cooperates with the lotus' releases and it's testing flows to confirm whether a tagged release is production ready:

Non-consensus breaking changes

• All PRs introduce non-consensus breaking changes can be merged to master as long they have maintainers' approvals.
• Roughly on a monthly basis, lotus will integrate ffi's head in master branch, for it's new feature release, and carry it through the testing flows.
  • release/lotus-vX will be created to determine the commit that lotus integrates in the corresponding release.
• If any bug is found during the testing, the fix should land in master then get backported to release/lotus-vX. The updated commit should be integrated into lotus and getting tested. Repeat the steps until it can be considered as stable.

#Consensus breaking changes*

• Consensus breaking changes should be developed in it's own branch, (branch name is suggested to be: feature branches feat/ or bug fix branches bug/).
• Consensus breaking changes that are scoped into the next immediate network upgrade shall land in next branch first. The maintainers are responsible to coordinate on when to land next to master according to lotus mandatory(network upgrade) release schedules.
• A new dev branch should be created and contributors are responsible to rebase the branch onto master/next as needed.

License

MIT or Apache 2.0