implementing-image-provenance-verification-with-cosign

# Implementing Image Provenance Verification with Cosign ## Overview Cosign is a Sigstore tool for signing, verifying, and attaching metadata to container images and OCI artifacts. It supports both key-based and keyless (OIDC) signing, integrates with Fulcio (certificate authority) and Rekor (transparency log), and enables supply chain security for container images. ## When to Use - When deploying or configuring implementing image provenance verification with cosign capabilities in your environment - When establishing security controls aligned to compliance requirements - When building or improving security architecture for this domain - When conducting security assessments that require this implementation ## Prerequisites - Cosign CLI installed - Docker or Podman for building images - OCI-compliant container registry (Docker Hub, GHCR, GCR, ECR) - OIDC provider account (GitHub, Google, Microsoft) for keyless signing ## Installing Cosign ```bash # Install via Go go install github.com/sigstore/cosign/v2/cmd/cosign@latest # Install via Homebrew brew install cosign # Install via script curl -O -L "https://github.com/sigstore/cosign/releases/latest/download/cosign-linux-amd64" sudo mv cosign-linux-amd64 /usr/local/bin/cosign sudo chmod +x /usr/local/bin/cosign # Verify installation cosign version ``` ## Key-Based Signing ### Generate Key Pair ```bash # Generate cosign key pair (creates cosign.key and cosign.pub) cosign generate-key-pair # Generate key pair stored ...