AgentSkillsCN

container-hardening

安全配置Docker镜像与容器运行时环境，实施非root用户、只读文件系统与安全上下文。在构建安全容器镜像或加固容器部署时加以运用。

SKILL.md
--- frontmatter
name: container-hardening
description: Secure Docker images and container runtime configurations. Implement non-root users, read-only filesystems, and security contexts. Use when building secure container images or hardening container deployments.
license: MIT
metadata:
  author: devops-skills
  version: "1.0"

Container Hardening

Secure container images and runtime configurations.

When to Use This Skill

Use this skill when:

  • •Building secure container images
  • •Hardening container deployments
  • •Meeting container security requirements
  • •Implementing defense in depth

Dockerfile Security

dockerfile
# Use minimal base image
FROM alpine:3.18

# Don't run as root
RUN addgroup -g 1001 -S appgroup && \
    adduser -u 1001 -S appuser -G appgroup

# Copy with specific ownership
COPY --chown=appuser:appgroup . /app

# Remove unnecessary packages
RUN apk del --purge build-dependencies && \
    rm -rf /var/cache/apk/*

# Use non-root user
USER appuser

# Read-only filesystem support
WORKDIR /app

Runtime Security

bash
# Run with security options
docker run -d \
  --read-only \
  --tmpfs /tmp \
  --security-opt=no-new-privileges:true \
  --cap-drop=ALL \
  --cap-add=NET_BIND_SERVICE \
  --user 1001:1001 \
  myapp:latest

Kubernetes Security Context

yaml
apiVersion: v1
kind: Pod
spec:
  securityContext:
    runAsNonRoot: true
    runAsUser: 1001
    fsGroup: 1001
  containers:
  - name: app
    securityContext:
      allowPrivilegeEscalation: false
      readOnlyRootFilesystem: true
      capabilities:
        drop: ["ALL"]

Image Scanning

bash
# Scan with Trivy
trivy image --severity HIGH,CRITICAL myapp:latest

# Use distroless images
FROM gcr.io/distroless/static-debian11

Best Practices

  • •Use minimal base images
  • •Run as non-root user
  • •Enable read-only filesystem
  • •Drop all capabilities
  • •Scan images regularly
  • •Sign and verify images
  • •Use secrets management

Related Skills