Security Best Practices

This guide covers security features, best practices, and production deployment considerations for the Refugio mountain refuge reservation system.

Built-in Security Features

The Refugio system implements several security measures to protect user data and prevent attacks.

Password Security

Bcrypt Password Hashing

The system uses PHP’s password_hash() function with PASSWORD_BCRYPT to securely store passwords.What this means:

Passwords are never stored in plain text
Each password has a unique salt
Even administrators cannot see user passwords
Passwords are verified using password_verify() during login

Implementation (from functions.php:75):

$password_hash = password_hash($datos['password'], PASSWORD_BCRYPT);

Verification (from login.php:19):

if ($user && password_verify($password, $user['password'])) {
    // Login successful
}

Session Security

Session Fixation Prevention

The system regenerates session IDs on login to prevent session fixation attacks.

Implementation (from login.php:20 and viewAdmin.php:14):

session_regenerate_id(true); // Prevents session fixation attacks

How it works:

User logs in with credentials
Old session ID is destroyed
New session ID is generated
User is associated with the new session

This prevents attackers from hijacking sessions by fixing session IDs.

Input Sanitization

XSS Protection

All user inputs are sanitized using the sanitize_input() function to prevent Cross-Site Scripting (XSS) attacks.

Implementation (from functions.php:1452):

function sanitize_input($data)
{
    $data = trim($data);                                    // Remove whitespace
    $data = stripslashes($data);                            // Remove backslashes
    $data = htmlspecialchars($data, ENT_QUOTES, 'UTF-8');  // Escape HTML entities
    return $data;
}

Usage (from viewAdmin.php:28-37):

$datos = [
    'num_socio' => sanitize_input($_POST['num_socio']),
    'dni'       => sanitize_input($_POST['dni']),
    'email'     => sanitize_input($_POST['email']),
    // ... all user inputs are sanitized
];

SQL Injection Prevention

Prepared Statements

All database queries use PDO prepared statements with parameter binding to prevent SQL injection.

Example (from functions.php:16):

$stmt = $conexion->prepare("SELECT id, email, password, rol, nombre, apellido1 FROM usuarios WHERE email = :email");
$stmt->bindParam(':email', $email);
$stmt->execute();

Why this is secure:

User input is never directly concatenated into SQL queries
Parameters are properly escaped by PDO
SQL injection attacks are effectively prevented

Role-Based Access Control

Authentication & Authorization

The system enforces role-based access control with strict session validation.

Admin panel protection (from viewAdmin.php:10-13):

if (!isset($_SESSION['userId']) || $_SESSION['rol'] !== 'admin') {
    header('Location: login.php');
    exit;
}

User panel protection (from viewSocio.php:11-14):

if (!isset($_SESSION['userId']) || ($_SESSION['rol'] ?? '') !== 'user') {
    header('Location: login.php');
    exit;
}

Protected admin user (from viewAdmin.php:52-58):

// Prevent modification of main admin account
$usuario_actual = obtener_usuario($conexionPDO, $id);
if ($usuario_actual && $usuario_actual['email'] === 'admin@hostel.com') {
    $mensaje = "No se puede modificar el usuario administrador principal";
    $tipo_mensaje = 'danger';
    break;
}

Password Management

Creating Strong Passwords

Minimum requirements

While the system doesn’t enforce complexity, follow these guidelines:

Minimum 8 characters (preferably 12+)
Mix of uppercase and lowercase letters
Include numbers and special characters
Avoid common words or personal information

Use a password manager

Consider using a password manager to:

Generate strong, unique passwords
Store passwords securely
Automatically fill login forms

Good password examples:

Tr4il$Runner2024!
M0unt@inH!ke#89
Refug10*Climb3r

Bad password examples (never use these):

password123
admin
123456
Your name or club name

Changing Your Password

For Members
For Administrators

Navigate to profile

Click Mi Perfil in the sidebar

Enter current password

Provide your current password for verification

Enter new password

Type your new strong password twice

Save changes

Click “Cambiar Contraseña”

Password Reset Workflow

If a user forgets their password:

User contacts administrator

User requests a password reset via secure communication

Administrator verifies identity

Admin confirms the user’s identity using member number and other details

Administrator resets password

Admin sets a temporary password via user edit form

Secure communication

Admin communicates the temporary password securely (in person, phone, or encrypted message)

User changes password

User logs in with temporary password and immediately changes it

Consider implementing a self-service password reset system with email verification for improved security and user experience.

HTTPS and Transport Security

Why HTTPS is Critical

Never run the Refugio system over HTTP in production. All data, including passwords, is transmitted in plain text over HTTP.

Without HTTPS:

Passwords sent in plain text during login
Session cookies can be intercepted
All user data is visible to network attackers
Man-in-the-middle attacks are possible

With HTTPS:

All communication is encrypted
Passwords and data are protected in transit
Session cookies are secure
Users can trust the connection

Implementing HTTPS

Obtain an SSL/TLS certificate

Options:

Let’s Encrypt: Free, automated certificates (recommended)
Commercial CA: Purchase from Digicert, Sectigo, etc.
Self-signed: Only for testing, never for production

Configure your web server

For Apache (httpd.conf or virtual host):

<VirtualHost *:443>
    ServerName refugio.yourclub.com
    
    SSLEngine on
    SSLCertificateFile /path/to/certificate.crt
    SSLCertificateKeyFile /path/to/private.key
    SSLCertificateChainFile /path/to/chain.crt
    
    # Strong SSL configuration
    SSLProtocol all -SSLv2 -SSLv3 -TLSv1 -TLSv1.1
    SSLCipherSuite HIGH:!aNULL:!MD5
    
    DocumentRoot /var/www/refugio
    # ... rest of configuration
</VirtualHost>

For Nginx (nginx.conf):

server {
    listen 443 ssl http2;
    server_name refugio.yourclub.com;
    
    ssl_certificate /path/to/certificate.crt;
    ssl_certificate_key /path/to/private.key;
    
    # Strong SSL configuration
    ssl_protocols TLSv1.2 TLSv1.3;
    ssl_ciphers HIGH:!aNULL:!MD5;
    ssl_prefer_server_ciphers on;
    
    root /var/www/refugio;
    # ... rest of configuration
}

Redirect HTTP to HTTPS

Force all traffic to use HTTPS:Apache (.htaccess):

RewriteEngine On
RewriteCond %{HTTPS} off
RewriteRule ^(.*)$ https://%{HTTP_HOST}%{REQUEST_URI} [L,R=301]

Nginx:

server {
    listen 80;
    server_name refugio.yourclub.com;
    return 301 https://$server_name$request_uri;
}

Test your configuration

Use SSL Labs SSL Test to verify:

Certificate is valid and trusted
Strong cipher suites are used
No security warnings
Grade A or A+ rating

Secure Session Cookies

Modify session settings for HTTPS (in conexion.php or main config file):

// Set secure session cookie parameters
ini_set('session.cookie_httponly', 1);  // Prevent JavaScript access
ini_set('session.cookie_secure', 1);     // Only send over HTTPS
ini_set('session.cookie_samesite', 'Strict'); // CSRF protection

session_start();

CSRF Protection

Current State

The current Refugio system does not implement CSRF tokens. This should be added for production deployments.

Implementing CSRF Protection

Generate CSRF token on login

Add to login.php after successful authentication:

// Generate CSRF token
$_SESSION['csrf_token'] = bin2hex(random_bytes(32));

Include token in all forms

Add a hidden field to every POST form:

<form method="post" action="viewAdmin.php">
    <input type="hidden" name="csrf_token" value="<?php echo $_SESSION['csrf_token']; ?>">
    <!-- rest of form fields -->
</form>

Validate token on submission

At the start of form processing:

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    // Verify CSRF token
    if (!isset($_POST['csrf_token']) || 
        $_POST['csrf_token'] !== $_SESSION['csrf_token']) {
        die('CSRF token validation failed');
    }
    
    // Process form...
}

Regenerate token after use (optional)

For extra security, regenerate after each request:

// After validating token
$_SESSION['csrf_token'] = bin2hex(random_bytes(32));

Production Deployment Checklist

Before deploying to production, ensure all security measures are in place:

Pre-Deployment Security

Critical Security Items

Disable error display

// In production configuration
ini_set('display_errors', 0);
ini_set('display_startup_errors', 0);
error_reporting(0);

// Log errors instead
ini_set('log_errors', 1);
ini_set('error_log', '/var/log/php-errors.log');

Remove development code

Remove or comment out (from viewAdmin.php:2-4 and viewSocio.php:6-8):

// DELETE THESE LINES IN PRODUCTION:
ini_set('display_errors', 1);
ini_set('display_startup_errors', 1);
error_reporting(E_ALL);

Secure database credentials

Store database credentials in a file outside the web root
Use environment variables for sensitive configuration
Restrict file permissions: chmod 600 config.php

Change default admin password

Change password for admin@hostel.com
Use a strong, unique password
Store it in a password manager

Enable HTTPS

Install valid SSL certificate
Configure secure session cookies
Redirect all HTTP to HTTPS

Implement CSRF protection

Add CSRF tokens to all forms
Validate tokens on submission

Server Configuration

Web Server Security

Restrict file permissions

# Set ownership
chown -R www-data:www-data /var/www/refugio

# Set directory permissions
find /var/www/refugio -type d -exec chmod 755 {} \;

# Set file permissions
find /var/www/refugio -type f -exec chmod 644 {} \;

# Protect sensitive files
chmod 600 /var/www/refugio/conexion.php

Disable directory listing

Apache (.htaccess):

Options -Indexes

Nginx:

autoindex off;

Protect sensitive files

Apache (.htaccess):

<FilesMatch "\.(ini|log|conf|sql)$">
    Require all denied
</FilesMatch>

Set security headers

Apache (.htaccess):

Header always set X-Frame-Options "DENY"
Header always set X-Content-Type-Options "nosniff"
Header always set X-XSS-Protection "1; mode=block"
Header always set Referrer-Policy "strict-origin-when-cross-origin"

Nginx:

add_header X-Frame-Options "DENY";
add_header X-Content-Type-Options "nosniff";
add_header X-XSS-Protection "1; mode=block";
add_header Referrer-Policy "strict-origin-when-cross-origin";

Database Security

MySQL/MariaDB Configuration

Use dedicated database user

-- Create database user with limited privileges
CREATE USER 'refugio_app'@'localhost' IDENTIFIED BY 'strong_password_here';

-- Grant only necessary privileges
GRANT SELECT, INSERT, UPDATE, DELETE ON refugio_db.* TO 'refugio_app'@'localhost';

-- Do NOT grant DROP, CREATE, ALTER in production
FLUSH PRIVILEGES;

Regular backups

Set up automated database backups:

# Example cron job (daily at 2 AM)
0 2 * * * mysqldump -u backup_user -p'password' refugio_db | gzip > /backups/refugio_$(date +\%Y\%m\%d).sql.gz

Restrict database access

-- Bind to localhost only (in my.cnf)
[mysqld]
bind-address = 127.0.0.1

File Upload Security

For profile photos (referenced in viewSocio.php):

Validate file types

The system already validates (from functions.php:1492):

$formatos_permitidos = ['image/jpeg', 'image/jpg', 'image/png', 'image/gif'];
$extensiones_permitidas = ['jpg', 'jpeg', 'png', 'gif'];

Limit file size

Maximum 5MB is enforced (from functions.php:1494):

$max_size = 5 * 1024 * 1024; // 5MB

Store uploads outside web root

Best practice: Store uploaded files outside the public web directory

$upload_dir = '/var/uploads/refugio/photos/';
// Serve files through a PHP script that validates access

Sanitize filenames

$filename = preg_replace('/[^a-zA-Z0-9._-]/', '', $filename);
$filename = uniqid() . '_' . $filename; // Prevent collisions

Monitoring and Auditing

Enable Logging

Implement comprehensive logging:

// Log authentication attempts
function log_auth_attempt($email, $success, $ip) {
    $status = $success ? 'SUCCESS' : 'FAILED';
    error_log("[AUTH] $status login attempt for $email from $ip");
}

// Log administrative actions
function log_admin_action($admin_id, $action, $details) {
    error_log("[ADMIN] User $admin_id performed $action: $details");
}

Monitor for Security Issues

Security Monitoring

Failed login attempts: Monitor for brute force attacks
Unusual reservation patterns: Detect abuse or suspicious activity
Database errors: Watch for SQL injection attempts
File upload attempts: Monitor for malicious file uploads
Session anomalies: Detect session hijacking attempts

Regular Security Audits

Weekly tasks

Review authentication logs for failed attempts
Check for unusual user account activity
Monitor reservation patterns

Monthly tasks

Review user accounts and remove inactive ones
Update dependencies (PHP, web server, database)
Check for security updates
Review and rotate admin passwords

Quarterly tasks

Full security audit
Penetration testing
Review and update security policies
Test backup restoration procedures

Incident Response

If you suspect a security breach:

Immediate actions

Take the system offline if actively being attacked
Change all admin passwords immediately
Review access logs for unauthorized access
Check database for unauthorized modifications

Investigation

Identify the breach vector: How did the attacker gain access?
Assess the damage: What data was accessed or modified?
Document everything: Keep detailed notes for analysis

Remediation

Patch the vulnerability that allowed the breach
Restore from clean backups if data was compromised
Implement additional security measures
Notify affected users if their data was compromised

Prevention

Conduct post-incident review
Update security procedures based on lessons learned
Implement additional monitoring
Provide security training to administrators

Additional Security Recommendations

Rate Limiting

Implement rate limiting to prevent brute force attacks:

// Example rate limiting for login attempts
function check_rate_limit($ip) {
    $max_attempts = 5;
    $time_window = 300; // 5 minutes
    
    // Check attempts from IP in time window
    // Implementation depends on your session/cache storage
    // Return true if allowed, false if rate limited
}

Two-Factor Authentication (Future Enhancement)

Consider implementing 2FA for administrator accounts:

Use TOTP (Time-based One-Time Password)
Libraries: GoogleAuthenticator, etc.
Require for all admin logins

Security Headers

Implement Content Security Policy (CSP):

header("Content-Security-Policy: default-src 'self'; script-src 'self' 'unsafe-inline' cdn.jsdelivr.net; style-src 'self' 'unsafe-inline' cdn.jsdelivr.net;");

Regular Updates

Keep all software up to date:

PHP version
Web server (Apache/Nginx)
Database (MySQL/MariaDB)
Operating system security patches

Summary

Security is an ongoing process, not a one-time setup. Regular monitoring, updates, and adherence to these best practices will keep your Refugio system secure and protect your users’ data. Key takeaways:

✅ Use HTTPS in production (mandatory)
✅ Implement CSRF protection
✅ Disable error display in production
✅ Use strong passwords and rotate regularly
✅ Monitor logs for suspicious activity
✅ Keep software updated
✅ Regular security audits
✅ Have an incident response plan

For technical implementation details, refer to the source code files referenced throughout this guide.

Get Started

Core Features

User Guides

Deployment

Documentation Index

​Security Best Practices

​Built-in Security Features

​Password Security

Bcrypt Password Hashing

​Session Security

Session Fixation Prevention

​Input Sanitization

XSS Protection

​SQL Injection Prevention

Prepared Statements

​Role-Based Access Control

Authentication & Authorization

​Password Management

​Creating Strong Passwords

​Changing Your Password

​Password Reset Workflow

​HTTPS and Transport Security

​Why HTTPS is Critical

​Implementing HTTPS

​Secure Session Cookies

​CSRF Protection

​Current State

​Implementing CSRF Protection

​Production Deployment Checklist

​Pre-Deployment Security

Critical Security Items

​Server Configuration

Web Server Security

​Database Security

MySQL/MariaDB Configuration

​File Upload Security

​Monitoring and Auditing

​Enable Logging

​Monitor for Security Issues

Security Monitoring

​Regular Security Audits

​Incident Response

​Additional Security Recommendations

​Rate Limiting

​Two-Factor Authentication (Future Enhancement)

​Security Headers

​Regular Updates

​Summary

Build docs developers (and LLMs) love

Security Best Practices

Built-in Security Features

Password Security

Session Security

Input Sanitization

SQL Injection Prevention

Role-Based Access Control

Password Management

Creating Strong Passwords

Changing Your Password

Password Reset Workflow

HTTPS and Transport Security

Why HTTPS is Critical

Implementing HTTPS

Secure Session Cookies

CSRF Protection

Current State

Implementing CSRF Protection

Production Deployment Checklist

Pre-Deployment Security

Server Configuration

Database Security

File Upload Security

Monitoring and Auditing

Enable Logging

Monitor for Security Issues

Regular Security Audits

Incident Response

Additional Security Recommendations

Rate Limiting

Two-Factor Authentication (Future Enhancement)

Security Headers

Regular Updates

Summary