The Complete Production SOP: How to Deploy and Run Docker Rootless Daemon Installation & Security Hardening in Autonomous AI Agents

---
name: "docker-rootless-daemon-hardening"
description: "Run the Docker daemon and containers completely without root privileges to mitigate breakouts."
metadata:
  author: "Moby Project"
  version: "1.0.0"
  runtime_compatibility:
    - "codex"
    - "claude-code"
    - "cursor"
    - "windsurf"
triggers:
  - "install docker rootless"
  - "setup rootless subuid subgid"
  - "harden docker daemon security"
permissions:
  fs_read: true
  fs_write: "workspace"
  shell_exec: true
  net_access: true
---

#!/usr/bin/env bash
set -euo pipefail

USER_NAME=$(whoami)
echo "Checking namespace availability for: ${USER_NAME}"

# Validate sysctl configuration
SYSCTL_VAL=$(sysctl -n kernel.unprivileged_userns_clone 2>/dev/null || echo "1")
if [[ "${SYSCTL_VAL}" -eq 0 ]]; then
  echo "ERROR: kernel.unprivileged_userns_clone is 0. Enable via sysctl." >&2
  exit 1
fi

# Validate subuid/subgid mapping
if ! grep -q "^${USER_NAME}:" /etc/subuid; then
  echo "ERROR: SubUID mapping missing for ${USER_NAME}" >&2
  exit 1
fi

echo "Namespace prerequisites satisfied."

# Export User Docker Runtime Configuration
export PATH=/usr/bin:$PATH
export DOCKER_HOST="unix://${XDG_RUNTIME_DIR}/docker.sock"

# Audit check to ensure client uses user-space socket
alias docker-info="docker info -f '{{json .SecurityOptions}}'"

#!/usr/bin/env bash
set -euo pipefail

# Ensure root inside container maps to non-root outside
CONTAINER_UID=$(docker run --rm alpine id -u)
if [[ "${CONTAINER_UID}" -ne 0 ]]; then
  echo "Container root isolation check failed." >&2
  exit 1
fi

# Verify rootless security option is reported by dockerd
SEC_OPTS=$(docker info --format '{{json .SecurityOptions}}')
if [[ "${SEC_OPTS}" != *"rootless"* ]]; then
  echo "CRITICAL: Docker daemon reports standard rootful execution!" >&2
  exit 1
fi

echo "SUCCESS: Docker rootless isolation verified."