raxol

# Security & Compliance

Comprehensive security practices and compliance guidelines for Raxol applications in enterprise environments.

## Overview

Security is paramount in enterprise terminal applications. This guide covers security best practices, vulnerability management, compliance frameworks, and security monitoring for Raxol applications.

> **📚 Architecture Context**: See [ADR-0006: Enterprise Security and Compliance Model](../../../adr/0006-enterprise-security-and-compliance-model.md) for the complete security architecture decisions and compliance framework details.

## Security Architecture

### Defense in Depth

```elixir
defmodule MyApp.Security do
  use Raxol.Enterprise.Security
  
  # Layer 1: Network Security
  network_security do
    firewall_rules [
      allow: [{:tcp, 443}, {:tcp, 4000}],
      deny: :all
    ]
    
    tls_config [
      versions: [:tlsv1_2, :tlsv1_3],
      ciphers: :strong,
      verify: :verify_peer
    ]
  end
  
  # Layer 2: Application Security
  application_security do
    enable :csrf_protection
    enable :xss_protection
    enable :sql_injection_prevention
    enable :command_injection_prevention
  end
  
  # Layer 3: Data Security
  data_security do
    encryption :at_rest, algorithm: :aes_256_gcm
    encryption :in_transit, protocol: :tls_1_3
    enable :data_masking
  end
end
```

## Input Validation & Sanitization

### Command Input Validation

```elixir
defmodule MyApp.CommandValidator do
  use Raxol.Enterprise.Security.Validation
  
  # Define allowed commands
  @allowed_commands ~w(ls pwd cd cat echo)
  @dangerous_patterns ~r/(rm|sudo|chmod|chown|dd|mkfs)/
  
  def validate_command(input) do
    with :ok <- check_length(input),
         :ok <- check_allowed_commands(input),
         :ok <- check_dangerous_patterns(input),
         :ok <- check_injection_attempts(input) do
      {:ok, sanitize(input)}
    else
      {:error, reason} -> {:error, reason}
    end
  end
  
  defp check_length(input) do
    if String.length(input) <= 1000 do
      :ok
    else
      {:error, :command_too_long}
    end
  end
  
  defp check_allowed_commands(input) do
    command = input |> String.split() |> List.first()
    
    if command in @allowed_commands do
      :ok
    else
      {:error, :command_not_allowed}
    end
  end
  
  defp check_dangerous_patterns(input) do
    if Regex.match?(@dangerous_patterns, input) do
      {:error, :dangerous_command}
    else
      :ok
    end
  end
  
  defp check_injection_attempts(input) do
    patterns = [
      ~r/[;&|`$]/,           # Command chaining
      ~r/\.\./,              # Directory traversal
      ~r/[\x00-\x1F\x7F]/    # Control characters
    ]
    
    if Enum.any?(patterns, &Regex.match?(&1, input)) do
      {:error, :potential_injection}
    else
      :ok
    end
  end
  
  defp sanitize(input) do
    input
    |> String.replace(~r/[^\w\s\-\.\/]/, "")
    |> String.trim()
  end
end
```

### Data Validation

```elixir
defmodule MyApp.DataValidator do
  use Raxol.Enterprise.Security.DataValidation
  
  schema :user_input do
    field :username, :string,
      required: true,
      format: ~r/^[a-zA-Z0-9_]+$/,
      length: [min: 3, max: 32]
    
    field :email, :string,
      required: true,
      format: ~r/^[\w._%+-]+@[\w.-]+\.[A-Za-z]{2,}$/
    
    field :age, :integer,
      required: false,
      range: [min: 0, max: 150]
    
    field :role, :string,
      required: true,
      enum: ["admin", "user", "guest"]
  end
  
  def validate_user_input(params) do
    case validate(params, :user_input) do
      {:ok, clean_data} ->
        {:ok, clean_data}
      {:error, errors} ->
        log_validation_failure(params, errors)
        {:error, errors}
    end
  end
end
```

## Encryption

### Data at Rest

```elixir
defmodule MyApp.Encryption do
  use Raxol.Enterprise.Crypto
  
  @key_rotation_days 90
  
  def encrypt_sensitive_data(data) do
    # Get current encryption key
    key = get_current_key()
    
    # Encrypt with AES-256-GCM
    case encrypt_aes_gcm(data, key) do
      {:ok, encrypted} ->
        # Store with key version for rotation
        {:ok, %{
          ciphertext: encrypted.ciphertext,
          nonce: encrypted.nonce,
          tag: encrypted.tag,
          key_version: key.version
        }}
      error -> error
    end
  end
  
  def decrypt_sensitive_data(encrypted_data) do
    # Get key by version
    key = get_key_version(encrypted_data.key_version)
    
    decrypt_aes_gcm(
      encrypted_data.ciphertext,
      key,
      encrypted_data.nonce,
      encrypted_data.tag
    )
  end
  
  # Key rotation
  def rotate_keys do
    with {:ok, new_key} <- generate_new_key(),
         :ok <- reencrypt_all_data(new_key),
         :ok <- mark_old_keys_retired() do
      {:ok, new_key}
    end
  end
end
```

### Data in Transit

```elixir
defmodule MyApp.TLS do
  use Raxol.Enterprise.Security.TLS
  
  def tls_options do
    [
      versions: [:"tlsv1.3", :"tlsv1.2"],
      ciphers: [
        "TLS_AES_256_GCM_SHA384",
        "TLS_AES_128_GCM_SHA256",
        "TLS_CHACHA20_POLY1305_SHA256"
      ],
      verify: :verify_peer,
      cacertfile: ca_bundle_path(),
      certfile: cert_path(),
      keyfile: key_path(),
      secure_renegotiate: true,
      reuse_sessions: true,
      honor_cipher_order: true
    ]
  end
end
```

## Audit Logging

### Comprehensive Audit Trail

```elixir
defmodule MyApp.AuditLogger do
  use Raxol.Enterprise.Audit
  
  # Define what to audit
  audit_events [
    :authentication,
    :authorization,
    :data_access,
    :data_modification,
    :configuration_change,
    :privilege_escalation,
    :security_event
  ]
  
  def log_event(event_type, details) do
    event = %{
      id: UUID.uuid4(),
      timestamp: DateTime.utc_now(),
      type: event_type,
      user: get_current_user(),
      session_id: get_session_id(),
      ip_address: get_client_ip(),
      details: details,
      hash: nil
    }
    
    # Create tamper-proof hash
    event_with_hash = Map.put(event, :hash, hash_event(event))
    
    # Store in multiple locations
    store_locally(event_with_hash)
    store_remotely(event_with_hash)
    
    # Alert on security events
    if event_type in [:privilege_escalation, :security_event] do
      send_security_alert(event_with_hash)
    end
  end
  
  defp hash_event(event) do
    event
    |> Map.delete(:hash)
    |> Jason.encode!()
    |> then(&:crypto.hash(:sha256, &1))
    |> Base.encode16()
  end
end
```

### Audit Log Analysis

```elixir
defmodule MyApp.AuditAnalysis do
  use Raxol.Enterprise.Security.Analysis
  
  def detect_anomalies do
    patterns = [
      multiple_failed_logins(),
      unusual_access_patterns(),
      privilege_escalation_attempts(),
      data_exfiltration_signs()
    ]
    
    case analyze_patterns(patterns) do
      [] -> :ok
      anomalies -> handle_anomalies(anomalies)
    end
  end
  
  defp multiple_failed_logins do
    %{
      pattern: :failed_login_burst,
      query: """
        SELECT user_id, COUNT(*) as attempts
        FROM audit_logs
        WHERE type = 'authentication'
        AND success = false
        AND timestamp > NOW() - INTERVAL '5 minutes'
        GROUP BY user_id
        HAVING COUNT(*) > 5
      """,
      severity: :high
    }
  end
end
```

## Vulnerability Management

### Security Scanning

```elixir
defmodule MyApp.SecurityScanner do
  use Raxol.Enterprise.Security.Scanner
  
  def scan_dependencies do
    # Check for known vulnerabilities
    case mix_audit() do
      {:ok, results} -> handle_audit_results(results)
      error -> error
    end
  end
  
  def scan_code do
    # Static analysis
    checks = [
      check_sql_injection(),
      check_command_injection(),
      check_xss_vulnerabilities(),
      check_sensitive_data_exposure(),
      check_insecure_random(),
      check_weak_crypto()
    ]
    
    Enum.map(checks, &run_check/1)
  end
  
  defp check_sql_injection do
    %{
      name: :sql_injection,
      pattern: ~r/Repo\.query\([^?]*#\{/,
      severity: :critical,
      message: "Potential SQL injection vulnerability"
    }
  end
end
```

### Patch Management

```elixir
defmodule MyApp.PatchManager do
  use Raxol.Enterprise.Security.Patches
  
  def check_updates do
    with {:ok, current} <- get_current_versions(),
         {:ok, available} <- get_available_updates(),
         {:ok, security} <- filter_security_updates(available) do
      
      if Enum.any?(security) do
        notify_security_updates(security)
        schedule_patching(security)
      end
      
      {:ok, security}
    end
  end
  
  def apply_security_patches do
    # Automated patching with rollback
    with {:ok, patches} <- get_pending_patches(),
         :ok <- create_backup(),
         :ok <- apply_patches(patches) do
      
      if verify_system_health() do
        {:ok, :patches_applied}
      else
        rollback_patches()
        {:error, :patch_failed}
      end
    end
  end
end
```

## Compliance Frameworks

### GDPR Compliance

```elixir
defmodule MyApp.GDPR do
  use Raxol.Enterprise.Compliance.GDPR
  
  # Data subject rights
  def export_user_data(user_id) do
    with {:ok, user} <- authorize_request(user_id),
         {:ok, data} <- collect_all_user_data(user_id),
         {:ok, formatted} <- format_for_export(data) do
      
      audit_log(:data_export, %{user_id: user_id})
      {:ok, formatted}
    end
  end
  
  def delete_user_data(user_id) do
    with {:ok, user} <- authorize_request(user_id),
         :ok <- verify_deletion_allowed(user_id),
         :ok <- anonymize_required_data(user_id),
         :ok <- delete_personal_data(user_id) do
      
      audit_log(:data_deletion, %{user_id: user_id})
      {:ok, :deleted}
    end
  end
  
  # Data protection
  def ensure_data_protection do
    [
      implement_privacy_by_design(),
      minimize_data_collection(),
      obtain_explicit_consent(),
      provide_transparency(),
      enable_data_portability()
    ]
  end
end
```

### SOC 2 Compliance

```elixir
defmodule MyApp.SOC2 do
  use Raxol.Enterprise.Compliance.SOC2
  
  # Security controls
  controls do
    # CC6.1 - Logical and Physical Access Controls
    control :access_control do
      implement :role_based_access
      implement :multi_factor_auth
      implement :session_management
      implement :password_policy
    end
    
    # CC6.6 - Encryption
    control :encryption do
      implement :data_at_rest_encryption
      implement :data_in_transit_encryption
      implement :key_management
    end
    
    # CC7.2 - System Monitoring
    control :monitoring do
      implement :security_monitoring
      implement :anomaly_detection
      implement :incident_response
    end
  end
end
```

## Security Headers

```elixir
defmodule MyAppWeb.SecurityHeaders do
  use Raxol.Enterprise.Security.Headers
  
  def call(conn, _opts) do
    conn
    |> put_security_headers()
    |> put_csp_header()
  end
  
  defp put_security_headers(conn) do
    conn
    |> put_resp_header("x-frame-options", "DENY")
    |> put_resp_header("x-content-type-options", "nosniff")
    |> put_resp_header("x-xss-protection", "1; mode=block")
    |> put_resp_header("referrer-policy", "strict-origin-when-cross-origin")
    |> put_resp_header("permissions-policy", "geolocation=(), microphone=(), camera=()")
    |> put_resp_header("strict-transport-security", "max-age=63072000; includeSubDomains; preload")
  end
  
  defp put_csp_header(conn) do
    csp = """
    default-src 'self';
    script-src 'self' 'unsafe-eval';
    style-src 'self' 'unsafe-inline';
    img-src 'self' data: https:;
    font-src 'self';
    connect-src 'self' wss://#{conn.host};
    frame-ancestors 'none';
    base-uri 'self';
    form-action 'self'
    """
    
    put_resp_header(conn, "content-security-policy", String.replace(csp, "\n", " "))
  end
end
```

## Incident Response

### Automated Response

```elixir
defmodule MyApp.IncidentResponse do
  use Raxol.Enterprise.Security.Incident
  
  def handle_security_incident(incident) do
    with :ok <- classify_incident(incident),
         :ok <- contain_threat(incident),
         :ok <- collect_forensics(incident),
         :ok <- notify_stakeholders(incident) do
      
      case incident.severity do
        :critical -> execute_emergency_response(incident)
        :high -> escalate_to_security_team(incident)
        :medium -> create_remediation_ticket(incident)
        :low -> log_for_analysis(incident)
      end
    end
  end
  
  defp contain_threat(incident) do
    case incident.type do
      :brute_force ->
        block_ip(incident.source_ip)
        lock_affected_accounts(incident.targets)
        
      :data_breach ->
        isolate_affected_systems()
        revoke_compromised_credentials()
        
      :malware ->
        quarantine_affected_nodes()
        block_malicious_domains()
    end
  end
end
```

## Best Practices

1. **Principle of Least Privilege**: Grant minimum necessary permissions
2. **Defense in Depth**: Multiple layers of security controls
3. **Zero Trust**: Verify everything, trust nothing
4. **Continuous Monitoring**: Real-time security monitoring
5. **Regular Updates**: Keep dependencies and systems patched
6. **Security Training**: Regular security awareness training
7. **Incident Preparedness**: Practice incident response procedures

## Security Checklist

- [ ] Enable authentication and authorization
- [ ] Implement input validation and sanitization
- [ ] Enable encryption at rest and in transit
- [ ] Configure security headers
- [ ] Set up audit logging
- [ ] Implement rate limiting
- [ ] Enable security monitoring
- [ ] Create incident response plan
- [ ] Conduct security assessments
- [ ] Train development team

## Next Steps

- Implement [Authentication](authentication.md) controls
- Set up [Monitoring](monitoring.md) for security events
- Review [Deployment](deployment.md) security practices
- Plan [Scaling](scaling.md) with security in mind