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Security: tonidy/pak-rt

Security

docs/SECURITY.md

RT Container Runtime - Security Features

This document describes the security features implemented in Task 12 of the RT Container Runtime project.

Overview

The RT Container Runtime implements comprehensive security features to ensure safe container operations, proper privilege management, and protection against common security vulnerabilities.

Security Features Implemented

1. Input Sanitization

All user inputs are sanitized to prevent injection attacks and ensure data integrity:

Container Name Sanitization

  • Function: sanitize_container_name()
  • Purpose: Removes dangerous characters from container names
  • Implementation: Strips non-alphanumeric characters except hyphens and underscores
  • Length Limit: Maximum 50 characters to prevent buffer overflow
# Example usage
sanitized_name=$(sanitize_container_name "user@input#123")
# Result: "userinput123"

Numeric Input Sanitization

  • Function: sanitize_numeric_input()
  • Purpose: Ensures memory and CPU limits contain only valid numbers
  • Implementation: Removes non-numeric characters and enforces maximum values
  • Protection: Prevents integer overflow and invalid resource specifications

File Path Sanitization

  • Function: sanitize_file_path()
  • Purpose: Prevents directory traversal attacks
  • Implementation: Removes ../ patterns and validates paths stay within base directory
  • Security: Protects against path injection vulnerabilities

2. Enhanced Privilege Management

Enhanced Privilege Checking

  • Function: check_enhanced_privileges()
  • Purpose: Validates specific capabilities required for different operations
  • Operations Supported:
    • namespace_operations: Requires CAP_SYS_ADMIN
    • network_operations: Requires CAP_NET_ADMIN
    • cgroup_operations: Requires write access to cgroup filesystem

Capability Verification

  • Function: check_capability()
  • Purpose: Verifies specific Linux capabilities are available
  • Implementation: Uses capsh when available, falls back to root check
  • Security: Ensures operations only proceed with proper permissions

3. Secure Temporary File Handling

Secure Temporary Files

  • Function: create_secure_temp_file()
  • Purpose: Creates temporary files with restricted permissions
  • Security Features:
    • Mode 600 (owner read/write only)
    • Automatic cleanup on script exit
    • Atomic operations to prevent race conditions

Secure Temporary Directories

  • Function: create_secure_temp_dir()
  • Purpose: Creates temporary directories with restricted access
  • Security Features:
    • Mode 700 (owner access only)
    • Automatic cleanup tracking
    • Protected against symlink attacks

4. Container Isolation Verification

Comprehensive Isolation Checks

  • Function: verify_container_isolation()
  • Purpose: Validates that containers are properly isolated
  • Checks Performed:
    • PID namespace isolation
    • Mount namespace isolation
    • Network namespace isolation
    • Cgroup resource isolation
    • Filesystem isolation

Individual Namespace Verification

  • PID Namespace: verify_pid_namespace_isolation()
  • Mount Namespace: verify_mount_namespace_isolation()
  • Network Namespace: verify_network_namespace_isolation()
  • Cgroup Isolation: verify_cgroup_isolation()
  • Filesystem Isolation: verify_filesystem_isolation()

5. Security Audit Functions

Comprehensive Security Auditing

  • Function: perform_security_audit()
  • Scopes Available:
    • all: Complete system and container audit
    • system: System-level security checks
    • container: Specific container security audit

System Security Audit

  • Function: audit_system_security()
  • Checks Performed:
    • Root privilege verification
    • Cgroup filesystem availability and permissions
    • Container directory security
    • World-writable file detection
    • Busybox binary security

Container Security Audit

  • Function: audit_container_security()
  • Checks Performed:
    • Container directory permissions
    • Configuration file security
    • Isolation verification for running containers
    • Orphaned resource detection

Security Command Interface

Security Audit Command

# Perform complete security audit
./rt.sh security-audit

# Audit system-level security only
./rt.sh security-audit system

# Audit specific container
./rt.sh security-audit container webapp

Enhanced Validation

Container Name Validation

  • Enhanced Security: Checks against forbidden system names
  • Forbidden Names: root, admin, system, kernel, init, proc, sys, dev, tmp, var, etc, bin, sbin, usr, lib, lib64
  • Input Sanitization: Validates that sanitization didn't change the input (detects malicious input)

Resource Limit Validation

  • Memory Limits: Enhanced with sanitization checks
  • CPU Limits: Enhanced with sanitization checks
  • Security: Detects and rejects inputs that required sanitization

Integration with Existing Functions

Container Creation Security

  • Enhanced privilege checking before container creation
  • Secure temporary file handling for configuration files
  • Isolation verification after container creation
  • Atomic file operations to prevent corruption

Metadata Security

  • Secure temporary files for container configuration
  • Atomic write operations
  • Proper file permissions (644 for config files)
  • Protected against race conditions

Testing

Security Test Suite

  • File: tests/security-tests.sh
  • Coverage: All security functions
  • Tests Include:
    • Input sanitization validation
    • Enhanced validation testing
    • Privilege checking verification
    • Secure temporary file handling
    • Isolation verification functions
    • Security audit functionality

Running Security Tests

# Run security tests specifically
./tests/security-tests.sh

# Run all tests including security
./tests/run-all-tests.sh

Security Best Practices Implemented

  1. Defense in Depth: Multiple layers of security checks
  2. Principle of Least Privilege: Specific capability checks for operations
  3. Input Validation: All user inputs are sanitized and validated
  4. Secure Defaults: Restrictive permissions on all created files
  5. Atomic Operations: Prevent race conditions and partial states
  6. Comprehensive Auditing: Regular security state verification
  7. Isolation Verification: Continuous validation of container boundaries

Analogi RT (Housing Complex Analogy)

Seperti RT yang mengatur keamanan kompleks perumahan:

  • Input Sanitization: RT memeriksa identitas pendaftar rumah baru
  • Privilege Management: RT memverifikasi wewenang untuk operasi tertentu
  • Secure File Handling: RT menyimpan dokumen dengan aman di arsip
  • Isolation Verification: RT memastikan setiap rumah terisolasi dengan baik
  • Security Audit: RT melakukan inspeksi keamanan kompleks secara berkala

Requirements Satisfied

This implementation satisfies the following requirements from the task:

  • ✅ Requirement 1.1: Enhanced namespace isolation with verification
  • ✅ Requirement 2.1: Secure network namespace management
  • ✅ Requirement 3.1: Protected cgroup resource management
  • ✅ Input sanitization for all user inputs
  • ✅ Enhanced privilege checking and validation
  • ✅ Secure temporary file handling
  • ✅ Container isolation verification
  • ✅ Comprehensive security audit functions

Future Security Enhancements

Potential areas for future security improvements:

  1. SELinux/AppArmor Integration: Additional mandatory access controls
  2. Seccomp Profiles: System call filtering for containers
  3. User Namespace Mapping: More sophisticated user isolation
  4. Network Security Policies: Container-to communication rules
  5. Resource Monitoring: Real-time security event detection
  6. Encrypted Storage: Protection for sensitive container data

There aren’t any published security advisories