chore(l2): include zkVM ELFs and VKs in the releases (#5244)

**Motivation**

We need releases of ethrex's ELFs and VKs to use independently for
proving L1 blocks execution.

**Description**

- Adds a `build-ethrex-guest` workflow to run with a mattrix strategy
(for sp1 and risc0) that builds the `guest_program` crate with the
features `sp1` and `risc0`. We need this as a separate job and cannot
reuse the builds from ubuntu-22.04 for l2_gpu because the guest program
being built there is different than the one we need for statelessly
verifying L1 blocks.
- Adds a `package-ethrex-guests` workflow to create
`ethrex-guests.tar.gz` compressing SP1 and RISC0 elf and vks.
- RISC0's ELF file is now generated.

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: 2 people

.github/workflows/tag_release.yaml

@@ -149,6 +149,111 @@ jobs:
           name: verification_keys
           path: verification_keys/
 
+  # There's a separate job to build the guest programs for SP1 and RISC0 since
+  # they need to be built without the l2 features.
+  build-ethrex-guest:
+    strategy:
+      matrix:
+        zkvm:
+          - sp1
+          - risc0
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Free Disk Space
+        uses: ./.github/actions/free-disk
+
+      - name: Setup Rust Environment
+        uses: ./.github/actions/setup-rust
+
+      - name: Install SP1
+        if: ${{ matrix.zkvm == 'sp1' }}
+        env:
+          SHELL: /bin/bash
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          curl -L https://sp1up.succinct.xyz | bash
+          ~/.sp1/bin/sp1up --version 5.0.8
+
+      - name: Install RISC0
+        if: ${{ matrix.zkvm == 'risc0' }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          curl -L https://risczero.com/install | bash
+          ~/.risc0/bin/rzup install cargo-risczero 3.0.3
+          ~/.risc0/bin/rzup install risc0-groth16
+          ~/.risc0/bin/rzup install rust
+
+      - name: Build ethrex elf - ${{ matrix.zkvm }}
+        run: |
+          cargo build --release --package guest_program --features ${{ matrix.zkvm }}
+          mkdir -p ${{ matrix.zkvm }}_verification_keys
+          if [ "${{ matrix.zkvm }}" = "sp1" ]; then
+            mv crates/l2/prover/src/guest_program/src/${{ matrix.zkvm }}/out/riscv32im-succinct-zkvm-elf ethrex-riscv32im-${{ matrix.zkvm }}-elf-${{ github.ref_name }}
+            mv crates/l2/prover/src/guest_program/src/${{ matrix.zkvm }}/out/riscv32im-succinct-zkvm-vk-bn254 ${{ matrix.zkvm }}_verification_keys/ethrex-riscv32im-${{ matrix.zkvm }}-vk-bn254-${{ github.ref_name }}
+            mv crates/l2/prover/src/guest_program/src/${{ matrix.zkvm }}/out/riscv32im-succinct-zkvm-vk-u32 ${{ matrix.zkvm }}_verification_keys/ethrex-riscv32im-${{ matrix.zkvm }}-vk-u32-${{ github.ref_name }}
+          elif [ "${{ matrix.zkvm }}" = "risc0" ]; then
+            mv crates/l2/prover/src/guest_program/src/${{ matrix.zkvm }}/out/riscv32im-risc0-elf ethrex-riscv32im-${{ matrix.zkvm }}-elf-${{ github.ref_name}}
+            mv crates/l2/prover/src/guest_program/src/${{ matrix.zkvm }}/out/riscv32im-risc0-vk ${{ matrix.zkvm }}_verification_keys/ethrex-riscv32im-${{ matrix.zkvm }}-vk-${{ github.ref_name}}
+          fi
+
+      - name: Upload ethrex guest elf artifact - ${{ matrix.zkvm }}
+        uses: actions/upload-artifact@v4
+        with:
+          name: ethrex-riscv32im-${{ matrix.zkvm }}-elf-${{ github.ref_name }}
+          path: ethrex-riscv32im-${{ matrix.zkvm }}-elf-${{ github.ref_name }}
+
+      - name: Upload ethrex guest verification keys - ${{ matrix.zkvm }}
+        uses: actions/upload-artifact@v4
+        with:
+          name: ${{ matrix.zkvm }}_verification_keys
+          path: ${{ matrix.zkvm }}_verification_keys/
+
+  # Creates ethrex-guests.tar.gz artifact including both SP1 and
+  # RISC0 elf and verification keys.
+  package-ethrex-guest:
+    needs:
+      - build-ethrex-guest
+    runs-on: ubuntu-latest
+    steps:
+      - name: Download SP1 elf artifact
+        uses: actions/download-artifact@v4
+        with:
+          name: ethrex-riscv32im-sp1-elf-${{ github.ref_name }}
+          path: ethrex_guests/sp1/
+
+      - name: Download SP1 verification keys artifacts
+        uses: actions/download-artifact@v4
+        with:
+          name: sp1_verification_keys
+          path: ethrex_guests/sp1/
+
+      - name: Download RISC0 elf artifact
+        uses: actions/download-artifact@v4
+        with:
+          name: ethrex-riscv32im-risc0-elf-${{ github.ref_name }}
+          path: ethrex_guests/risc0/
+
+      - name: Download RISC0 verification keys artifacts
+        uses: actions/download-artifact@v4
+        with:
+          name: risc0_verification_keys
+          path: ethrex_guests/risc0/
+
+      - name: Archive ethrex guests
+        run: |
+          cd ethrex_guests/
+          tar -czvf ../ethrex-guests.tar.gz .
+
+      - name: Upload ethrex guests artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: ethrex-guests.tar.gz
+          path: ethrex-guests.tar.gz
+
   package-contracts:
     needs:
       - build-ethrex
@@ -221,8 +326,10 @@ jobs:
   finalize-release:
     needs:
       - build-ethrex
+      - build-ethrex-guest
       - build-docker
       - package-contracts
+      - package-ethrex-guest
     runs-on: ubuntu-latest
     steps:
       - name: Checkout Code
@@ -234,7 +341,7 @@ jobs:
         uses: actions/download-artifact@v4
         with:
           path: ./bin
-          pattern: "ethrex*"
+          pattern: "ethrex*" # This includes the binaries, elf files, ethrex-verification-keys.tar.gz, and ethrex-contracts.tar.gz
 
       - name: Get previous tag
         run: |

crates/l2/prover/src/guest_program/build.rs

@@ -33,11 +33,15 @@ fn build_risc0_program() {
         "zkvm-risc0-program",
         guest_options,
     )]));
+    let elf = built_guests[0].elf.clone();
     let image_id = built_guests[0].image_id;
 
     // this errs if the dir already exists, so we don't handle an error.
     let _ = std::fs::create_dir("./src/risc0/out");
 
+    std::fs::write("./src/risc0/out/riscv32im-risc0-elf", &elf)
+        .expect("could not write Risc0 elf to file");
+
     std::fs::write(
         "./src/risc0/out/riscv32im-risc0-vk",
         format!("0x{}\n", hex::encode(image_id.as_bytes())),