IBC-independent Ethereum light client types

[yoshidan]

Summary

Adds the ethereum-light-client-types repository — a set of shared type definitions, validation utilities, and prover helpers for Ethereum light client implementations.
The goal is to extract the IBC-independent core out of ethereum-ibc-rs so it can be reused by both
ethereum-elc and optimism-elc instead of each ELC re-implementing the same logic.

What this provides

Rust

Crate	Description
ethereum-light-client-types (type/)	Core types, traits, validation, and error definitions (no_std)
ethereum-light-client-proto (proto/)	Protobuf definitions and generated Rust code

Modules in ethereum-light-client-types:

• client_state / consensus_state — trait definitions shared by the ELCs
• consensus — consensus update structures and Proto conversions
• update — sync committee state-transition logic
• validate — validation utilities for consensus / execution updates
• commitment — IBC commitment storage-slot calculation and verification
• membership — membership / non-membership proof verification
• time — timestamp validation utilities
• errors — error types for all operations

Go

Prover-side helpers under prover/ (relay, beacon, execution, types, proto) used by the downstream relayer-provers to build proofs and fork parameters.

[Copilot]

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

Adds the initial implementation of the ethereum-light-client-types repository, extracting IBC-independent Ethereum light client types, validation, and prover-side helpers for reuse across multiple ELC implementations.

Changes:

• Introduces the Rust ethereum-light-client-types crate (core types/traits, validation, membership/time utilities) and the ethereum-light-client-proto crate (protobuf definitions + generated Rust).
• Adds a Go prover helper library (beacon/execution clients, SSZ/Merkle proof helpers, fork schedule/spec helpers, and generated proto types).
• Adds build/test/lint tooling (workspace setup, CI workflow, proto generation scripts).

Reviewed changes

Copilot reviewed 50 out of 54 changed files in this pull request and generated 9 comments.

Show a summary per file

File	Description
type/src/lib.rs	Defines the ethereum-light-client-types crate surface and module layout.
type/src/client_state.rs	Introduces the ClientState trait used by shared verification logic.
type/src/consensus_state.rs	Introduces the ConsensusState trait used for proof verification inputs.
type/src/consensus.rs	Adds core consensus/execution update structs + proto conversion helpers.
type/src/commitment.rs	Adds IBC commitment storage key calculation + account storage root verification.
type/src/membership.rs	Adds membership/non-membership verification over MPT proofs with shared arg validation.
type/src/time.rs	Adds timestamp construction and header/trusting-period validation utilities.
type/src/update.rs	Adds sync committee state-transition helpers and store reader adapter.
type/src/validate.rs	Adds execution update (block-hash) validation against finalized execution root.
type/src/errors.rs	Centralizes error variants for core operations and conversions.
type/Cargo.toml	Declares Rust crate dependencies (no_std-oriented) and dev-deps.
proto/definitions/ibc/lightclients/ethereum/v1/ethereum.proto	Defines protobuf messages for ethereum light client types.
proto/src/lib.rs	Exposes generated prost modules and IBC commit metadata.
proto/src/prost/ibc.lightclients.ethereum.v1.rs	Adds generated Rust prost types for the ethereum light client proto package.
proto/src/IBC_GO_COMMIT	Pins the ibc-go commit used for proto generation consistency.
proto/Cargo.toml	Declares the ethereum-light-client-proto crate and dependencies.
proto-compiler/src/main.rs	Adds a small Rust CLI entrypoint for proto compilation.
proto-compiler/src/cmd/compile.rs	Implements proto compilation into Rust using tonic_build.
proto-compiler/src/cmd.rs	Wires proto-compiler subcommands.
proto-compiler/src/cmd/clone.rs	Placeholder for future clone functionality.
proto-compiler/README.md	Documents proto-compiler requirements and usage.
proto-compiler/Cargo.toml	Declares proto-compiler tool dependencies.
proto-compiler/.gitignore	Ignores proto-compiler build artifacts.
prover/types/ethereum.go	Adds basic validation helpers for Go protobuf-generated update types.
prover/relay/update.go	Adds helpers to build execution updates (optionally including block hash) for L2s.
prover/relay/update_test.go	Tests execution update building with/without block hash.
prover/relay/ssz.go	Adds SSZ chunk hashing + generalized merkle proof generation helpers.
prover/relay/ssz_test.go	Tests merkle proof generation and SSZ helper outputs.
prover/relay/spec.go	Adds fork spec constants and fork schedule parameters for networks.
prover/relay/spec_test.go	Tests fork schedule helpers and spec sanity checks.
prover/relay/slot.go	Adds slot/epoch/period computation helpers and blockNumber->period derivation.
prover/relay/slot_test.go	Tests slot/epoch/period calculations across presets.
prover/relay/proof.go	Adds IBC commitment slot/key helpers and proof-building helpers.
prover/relay/proof_test.go	Tests IBC commitments slot and storage key derivation.
prover/relay/bootstrap.go	Adds bootstrap discovery for a given sync committee period via Beacon API.
prover/relay/bootstrap_test.go	Tests bootstrap discovery logic with a mock beacon fetcher.
prover/execution/client.go	Introduces an execution client interface abstraction (HeaderByNumber).
prover/execution/helpers.go	Adds a helper for fetching execution block timestamps.
prover/beacon/client.go	Adds a Beacon API client with a Fetcher abstraction and version gating.
prover/beacon/response.go	Defines JSON response types and parsing for the Beacon API.
prover/beacon/types.go	Adds type adapters and proto conversion helpers for beacon data.
prover/proto/protocgen.sh	Adds buf-driven Go proto generation script and output staging.
prover/proto/buf.yaml	Configures buf module deps and lint/breaking settings for Go protos.
prover/proto/buf.gen.gogo.yaml	Configures buf plugins for gogo + grpc-gateway generation.
go.mod	Declares Go module deps for prover helpers and proto generation runtime.
Cargo.toml	Creates a Rust workspace for type + proto crates (excluding proto-compiler).
rust-toolchain	Pins the Rust toolchain used for builds.
Makefile	Adds proto generation and lint/fmt targets for Rust and Go workflows.
.github/workflows/test.yml	Adds CI for Rust tests/lint and Go prover tests.
README.md	Documents repository purpose and usage for Rust crates and Go prover packages.

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[Copilot]

Pull request overview

Copilot reviewed 50 out of 54 changed files in this pull request and generated 6 comments.

[Copilot]

Pull request overview

Copilot reviewed 50 out of 54 changed files in this pull request and generated 3 comments.