feat: bundle Imp guest kernel

.github/workflows/ci.yml

@@ -23,6 +23,9 @@ jobs:
           curl -sfL "https://github.com/gitleaks/gitleaks/releases/download/${GITLEAKS_VERSION}/gitleaks_${GITLEAKS_VERSION#v}_linux_x64.tar.gz" \
             | tar -xz -C /usr/local/bin gitleaks
 
+      - name: Verify extension pins and paths
+        run: ./hack/verify.sh
+
       - name: Gitleaks secret scan
         run: gitleaks detect --source . --redact
 

.github/workflows/export-cosign-public-key.yml

@@ -0,0 +1,21 @@
+name: Export Cosign public key
+
+on:
+  workflow_dispatch:
+
+jobs:
+  export:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+
+    steps:
+      - name: Install Cosign
+        uses: sigstore/cosign-installer@6f9f17788090df1f26f669e9d70d6ae9567deba6 # v3.8.1
+
+      - name: Export public key
+        env:
+          COSIGN_PRIVATE_KEY: ${{ secrets.COSIGN_PRIVATE_KEY }}
+          COSIGN_PASSWORD: ${{ secrets.COSIGN_PASSWORD }}
+        run: |
+          cosign public-key --key env://COSIGN_PRIVATE_KEY

Dockerfile

@@ -5,32 +5,46 @@
 ARG FIRECRACKER_VERSION=v1.15.0
 ARG FIRECRACKER_SHA256_X86_64=00cadf7f21e709e939dc0c8d16e2d2ce7b975a62bec6c50f74b421cc8ab3cab4
 ARG FIRECRACKER_SHA256_AARCH64=58325e6c3c539482a412ec0b60e6f539c3320adebcf8179c7629d06736aee0bd
+ARG FIRECRACKER_CI_PREFIX=https://s3.amazonaws.com/spec.ccfc.min/firecracker-ci/v1.15
+ARG KERNEL_VERSION=6.1.155
+ARG KERNEL_SHA256_X86_64=e20e46d0c36c55c0d1014eb20576171b3f3d922260d9f792017aeff53af3d4f2
+ARG KERNEL_SHA256_AARCH64=e3544b10603acbf3db492cb52e000d22ba202cb4b63b9add027565683e11c591
 
 # -- download stage -----------------------------------------------------------
 FROM --platform=${BUILDPLATFORM} alpine:3.21 AS download
 ARG FIRECRACKER_VERSION
 ARG FIRECRACKER_SHA256_X86_64
 ARG FIRECRACKER_SHA256_AARCH64
+ARG FIRECRACKER_CI_PREFIX
+ARG KERNEL_VERSION
+ARG KERNEL_SHA256_X86_64
+ARG KERNEL_SHA256_AARCH64
 ARG TARGETARCH
 
 # hadolint ignore=DL3018
 RUN apk add --no-cache curl && \
     case "${TARGETARCH}" in \
-      amd64) ARCH="x86_64"; SHA256="${FIRECRACKER_SHA256_X86_64}" ;; \
-      arm64) ARCH="aarch64"; SHA256="${FIRECRACKER_SHA256_AARCH64}" ;; \
+      amd64) ARCH="x86_64"; FIRECRACKER_SHA256="${FIRECRACKER_SHA256_X86_64}"; KERNEL_SHA256="${KERNEL_SHA256_X86_64}" ;; \
+      arm64) ARCH="aarch64"; FIRECRACKER_SHA256="${FIRECRACKER_SHA256_AARCH64}"; KERNEL_SHA256="${KERNEL_SHA256_AARCH64}" ;; \
       *) echo "Unsupported architecture: ${TARGETARCH}" >&2 && exit 1 ;; \
     esac && \
     URL="https://github.com/firecracker-microvm/firecracker/releases/download/${FIRECRACKER_VERSION}/firecracker-${FIRECRACKER_VERSION}-${ARCH}.tgz" && \
     curl -fsSL "${URL}" -o /tmp/firecracker.tgz && \
-    printf '%s  %s\n' "${SHA256}" "/tmp/firecracker.tgz" > /tmp/firecracker.sha256 && \
+    printf '%s  %s\n' "${FIRECRACKER_SHA256}" "/tmp/firecracker.tgz" > /tmp/firecracker.sha256 && \
     sha256sum -c /tmp/firecracker.sha256 && \
     tar -xzf /tmp/firecracker.tgz -C /tmp && \
     install -Dm755 \
       "/tmp/release-${FIRECRACKER_VERSION}-${ARCH}/firecracker-${FIRECRACKER_VERSION}-${ARCH}" \
       /out/rootfs/usr/local/bin/firecracker && \
     install -Dm755 \
       "/tmp/release-${FIRECRACKER_VERSION}-${ARCH}/jailer-${FIRECRACKER_VERSION}-${ARCH}" \
-      /out/rootfs/usr/local/bin/jailer
+      /out/rootfs/usr/local/bin/jailer && \
+    KERNEL_URL="${FIRECRACKER_CI_PREFIX}/${ARCH}/vmlinux-${KERNEL_VERSION}" && \
+    curl -fsSL "${KERNEL_URL}" -o /tmp/vmlinux && \
+    printf '%s  %s\n' "${KERNEL_SHA256}" /tmp/vmlinux > /tmp/vmlinux.sha256 && \
+    sha256sum -c /tmp/vmlinux.sha256 && \
+    test -s /tmp/vmlinux && \
+    install -Dm0644 /tmp/vmlinux /out/rootfs/usr/local/share/imp/vmlinux
 
 # -- extension image ----------------------------------------------------------
 # Files under /rootfs/ are overlaid onto the Talos node filesystem at boot.

README.md

@@ -5,22 +5,23 @@
 [![Publish](https://github.com/syscode-labs/talos-ext-firecracker/actions/workflows/release.yml/badge.svg)](https://github.com/syscode-labs/talos-ext-firecracker/actions/workflows/release.yml)
 [![GHCR](https://img.shields.io/badge/registry-ghcr.io-blue)](https://ghcr.io/syscode-labs/talos-ext-firecracker)
 [![Talos](https://img.shields.io/badge/talos-%3E%3D1.7-0f62fe)](https://www.talos.dev/)
-[![Firecracker](https://img.shields.io/badge/firecracker-v1.9.0-orange)](https://github.com/firecracker-microvm/firecracker/releases/tag/v1.9.0)
+[![Firecracker](https://img.shields.io/badge/firecracker-v1.15.0-orange)](https://github.com/firecracker-microvm/firecracker/releases/tag/v1.15.0)
 [![Platforms](https://img.shields.io/badge/platforms-amd64%20%7C%20arm64-brightgreen)](#)
 [![License](https://img.shields.io/badge/license-Apache--2.0-green)](https://www.apache.org/licenses/LICENSE-2.0)
 
 This repo builds a **Talos system extension** that adds:
 
 - `firecracker`
 - `jailer`
+- `/usr/local/share/imp/vmlinux` (Firecracker CI guest kernel, `6.1.155`)
 
 In plain terms: it gives a Talos node the Firecracker binaries so that higher-level systems can start lightweight microVMs.
 
 ## What This Does
 
-1. Downloads Firecracker release tarballs for `amd64` and `arm64`
-2. Verifies tarball checksums before extracting
-3. Packages binaries into a Talos extension image
+1. Downloads Firecracker release tarballs and the pinned Firecracker CI guest kernel for `amd64` and `arm64`
+2. Verifies all artifact checksums before installing them
+3. Packages Firecracker, Jailer, and the Imp guest kernel into a Talos extension image
 4. Publishes multi-arch images to GHCR on tagged releases
 5. Signs the pushed image digest recursively with Cosign so Image Factory can verify it
 
@@ -54,6 +55,19 @@ retired key.
 
 ## Quick Start
 
+## Use With Imp
+
+The Imp Helm chart must mount the kernel installed by this extension:
+
+```yaml
+agent:
+  env:
+    kernelPath: /usr/local/share/imp/vmlinux
+```
+
+This path is Talos-specific. Local and Kind-based Imp tests provision their own
+kernel at `/var/lib/imp/vmlinux` and should retain that configuration.
+
 Build locally:
 
 ```bash
@@ -63,6 +77,7 @@ docker buildx build --platform linux/amd64,linux/arm64 -t talos-ext-firecracker:
 Run local checks:
 
 ```bash
+./hack/verify.sh
 pre-commit run --all-files
 ```
 
@@ -75,8 +90,9 @@ pre-commit install --hook-type commit-msg
 
 ## Key Files
 
-- [`Dockerfile`](Dockerfile): downloads, verifies, and installs Firecracker binaries
+- [`Dockerfile`](Dockerfile): downloads, verifies, and installs Firecracker, Jailer, and the pinned Imp guest kernel
 - [`manifest.yaml`](manifest.yaml): Talos extension metadata
+- [`hack/verify.sh`](hack/verify.sh): validates artifact pins and installed paths
 - [`.github/workflows/ci.yml`](.github/workflows/ci.yml): lint/build checks
 - [`.github/workflows/release-please.yml`](.github/workflows/release-please.yml): automated release PRs
 - [`.github/workflows/release.yml`](.github/workflows/release.yml): publish on tags

hack/verify.sh

@@ -0,0 +1,61 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+DOCKERFILE="${ROOT_DIR}/Dockerfile"
+MANIFEST="${ROOT_DIR}/manifest.yaml"
+
+fail() {
+  echo "verification failed: $*" >&2
+  exit 1
+}
+
+require_file() {
+  [[ -f "$1" ]] || fail "missing file: $1"
+}
+
+require_file "${DOCKERFILE}"
+require_file "${MANIFEST}"
+
+grep -q '^  name: firecracker$' "${MANIFEST}" || fail "manifest name is not pinned"
+grep -Eq '^  version: [0-9]+\.[0-9]+\.[0-9]+([-.][0-9A-Za-z.]+)?$' "${MANIFEST}" \
+  || fail "manifest version is not a semantic version"
+grep -q 'pinned Imp guest vmlinux' "${MANIFEST}" || fail "manifest description is missing the guest kernel"
+
+grep -q 'FIRECRACKER_VERSION=v1\.15\.0' "${DOCKERFILE}" || fail "Firecracker version is not pinned"
+grep -q 'FIRECRACKER_CI_PREFIX=https://s3\.amazonaws\.com/spec\.ccfc\.min/firecracker-ci/v1\.15' "${DOCKERFILE}" \
+  || fail "guest kernel source is not pinned"
+grep -q 'KERNEL_VERSION=6\.1\.155' "${DOCKERFILE}" || fail "guest kernel version is not pinned"
+
+for digest in \
+  00cadf7f21e709e939dc0c8d16e2d2ce7b975a62bec6c50f74b421cc8ab3cab4 \
+  58325e6c3c539482a412ec0b60e6f539c3320adebcf8179c7629d06736aee0bd \
+  e20e46d0c36c55c0d1014eb20576171b3f3d922260d9f792017aeff53af3d4f2 \
+  e3544b10603acbf3db492cb52e000d22ba202cb4b63b9add027565683e11c591; do
+  grep -q "${digest}" "${DOCKERFILE}" || fail "missing SHA-256 pin: ${digest}"
+done
+
+grep -q 'amd64) ARCH="x86_64"' "${DOCKERFILE}" || fail "amd64 architecture mapping is missing"
+grep -q 'arm64) ARCH="aarch64"' "${DOCKERFILE}" || fail "arm64 architecture mapping is missing"
+
+for path in \
+  /usr/local/bin/firecracker \
+  /usr/local/bin/jailer \
+  /usr/local/share/imp/vmlinux; do
+  grep -q "${path}" "${DOCKERFILE}" || fail "required installed path is missing: ${path}"
+done
+
+if [[ "${VERIFY_REMOTE:-false}" == "true" ]]; then
+  command -v curl >/dev/null 2>&1 || fail "curl is required for VERIFY_REMOTE=true"
+  command -v sha256sum >/dev/null 2>&1 || fail "sha256sum is required for VERIFY_REMOTE=true"
+
+  tmp_dir="$(mktemp -d)"
+  trap 'rm -rf "${tmp_dir}"' EXIT
+  base="https://s3.amazonaws.com/spec.ccfc.min/firecracker-ci/v1.15"
+  curl -fsSL "${base}/x86_64/vmlinux-6.1.155" -o "${tmp_dir}/x86_64"
+  curl -fsSL "${base}/aarch64/vmlinux-6.1.155" -o "${tmp_dir}/aarch64"
+  printf '%s  %s\n' e20e46d0c36c55c0d1014eb20576171b3f3d922260d9f792017aeff53af3d4f2 "${tmp_dir}/x86_64" | sha256sum -c -
+  printf '%s  %s\n' e3544b10603acbf3db492cb52e000d22ba202cb4b63b9add027565683e11c591 "${tmp_dir}/aarch64" | sha256sum -c -
+fi
+
+echo "Firecracker extension pins and installed paths verified"

manifest.yaml

@@ -3,7 +3,7 @@ metadata:
   name: firecracker
   version: 1.12.0
   author: syscode-labs
-  description: Firecracker microVM and Jailer binaries for Talos Linux
+  description: Firecracker microVM, Jailer, and pinned Imp guest vmlinux for Talos Linux
   compatibility:
     talos:
       version: '>= 1.7.0'