CHIA-193: Rust bindings to chiapos (#439)

Adds a Rust crate with a memory safe (at least, according to fuzz tests
and unit tests I've written) binding to `validate_proof`. This is part
of an effort to port block prevalidation to Rust.

.github/workflows/rust.yml

@@ -0,0 +1,89 @@
+name: Rust bindings
+
+on:
+  push:
+    branches:
+      - main
+  release:
+    types: [published]
+  pull_request:
+    branches:
+      - "**"
+
+permissions:
+  id-token: write
+  contents: read
+
+jobs:
+  fuzz_targets:
+    name: Run fuzzers
+    runs-on: ubuntu-latest
+    env:
+      CARGO_PROFILE_RELEASE_LTO: false
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@nightly
+
+      - name: Install cargo-fuzz
+        run: cargo +nightly install cargo-fuzz
+
+      - name: Cargo fuzz
+        run: |
+          cd rust-bindings
+          cargo fuzz list | xargs -I "%" sh -c "cargo +nightly fuzz run % -- -max_total_time=600 || exit 255"
+
+  build_crate:
+    name: Build crate
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Set up Rust
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          components: rustfmt, clippy
+
+      - name: Rustfmt
+        run: cargo fmt -- --files-with-diff --check
+
+      - name: Clippy
+        run: cargo clippy
+
+      - name: Tests
+        run: cargo test && cargo test --release
+
+      - name: Build
+        run: cargo build --release
+
+      - name: Prepare for publish
+        run: |
+          mkdir rust-bindings/cpp
+          cp -r src lib tests uint128_t python-bindings c-bindings CMakeLists.txt rust-bindings/cpp
+
+      - name: Publish to crates.io (dry run)
+        # We use `--allow-dirty` because the `cpp` folder is copied into the working directory.
+        # This is necessary because the `cpp` folder is not part of the crate otherwise.
+        run: cargo publish --dry-run -p chiapos --allow-dirty
+
+      - name: Upload crate artifacts
+        uses: actions/upload-artifact@v4
+        with:
+          name: crate
+          path: ./target/package/*-*.crate
+
+      - name: Set Env
+        uses: Chia-Network/actions/setjobenv@main
+        env:
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Publish to crates.io
+        if: env.RELEASE == 'true'
+        env:
+          CARGO_REGISTRY_TOKEN: ${{ secrets.cargo_registry_token }}
+        # See comment above for why `--allow-dirty` is used.
+        run: cargo publish -p chiapos --allow-dirty

.gitignore

@@ -31,4 +31,5 @@ build-*
 cmake-build*
 *.zip
 *.tar.gz
-libs/
+libs/
+target/

CMakeLists.txt

@@ -156,7 +156,15 @@ include_directories(
 option(BUILD_PROOF_OF_SPACE_STATICALLY "Build ProofOfSpace target statically" OFF)
 IF (BUILD_PROOF_OF_SPACE_STATICALLY)
   message("Statically build ProofOfSpace")
-  target_link_libraries(ProofOfSpace -static -Wl,--whole-archive -lrt -lpthread -Wl,--no-whole-archive)
+  target_link_libraries(ProofOfSpace PUBLIC -static -Wl,--whole-archive -lrt -lpthread -Wl,--no-whole-archive)
+ENDIF()
+
+option(BUILD_STATIC_CHIAPOS_LIBRARY "Build chiapos static library (verify-only)" OFF)
+IF (BUILD_STATIC_CHIAPOS_LIBRARY)
+  message("Build chiapos static library (verify-only)")
+  add_library(chiapos_static STATIC src/chacha8.c c-bindings/wrapper.cpp)
+  target_link_libraries(chiapos_static PUBLIC blake3)
+  target_include_directories(chiapos_static PUBLIC lib/include)
 ENDIF()
 
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