A final version of the report.

LICENCE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 Christos Choutouridis <cchoutou@ece.auth.gr>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

Readme.md

@@ -0,0 +1,75 @@
+# Password Manager Security Assignment
+
+## About
+
+This repository contains an improved and secured version of a simplified web-based password manager.
+The project was developed in the context of a university assignment on Aristotle's University of Thessaloniki(AUTh) Information Systems Security class.
+The original application intentionally contained multiple security vulnerabilities.
+The purpose of this work was to identify, analyze, and mitigate these vulnerabilities using well-established security practices.
+
+The application is implemented in PHP and uses a MySQL database for data storage.
+The deployment is fully containerized using Docker and Docker Compose, ensuring reproducibility and ease of execution across different operating systems.
+
+## Architecture Overview
+
+The application is deployed as a multi-container system.
+Each component has a clearly defined role and responsibility.
+All services are isolated and communicate only through Docker-managed networks.
+
+Components:
+- Web Application (PHP)
+- Database (MySQL)
+- Reverse Proxy and HTTPS (Caddy)
+
+## Deployment Instructions
+
+The deployment process is identical for Linux and Windows.
+The only requirement is a working Docker installation.
+
+### Prerequisites
+
+- Docker
+- Docker Compose (included in modern Docker installations)
+
+No additional software such as Apache, PHP, or MySQL is required on the host system.
+
+### Deployment on Linux
+
+1. Open a terminal.
+2. Navigate to the project directory containing `docker-compose.yml`.
+3. Run the following command:
+    ```bash
+    docker compose up -d --build
+    ```
+4. Wait until all containers are built and started.
+5. Access the application through your browser using: https://localhost
+
+### Deployment on Windows
+
+1. Install Docker Desktop for Windows.
+2. Ensure that WSL2 is enabled (Docker Desktop will guide you automatically).
+3. Open PowerShell or Command Prompt.
+4. Navigate to the project directory containing docker-compose.yml.
+5. Run the following command:
+    ```bash
+    docker compose up -d --build
+    ```
+6. Once the containers are running, open a browser and navigate to: https://localhost
+
+### Notes on Reproducibility
+
+The use of Docker ensures that:
+- The application behaves identically on all supported operating systems
+- No manual configuration of web servers or databases is required
+- Environment-specific issues are minimized
+
+This approach allows evaluators to focus on the security aspects of the application rather than deployment complexity.
+
+## Disclaimer
+
+This project was developed solely for educational purposes.
+It is provided "as is", without any express or implied warranties.
+The author assumes no responsibility for any misuse, data loss, security incidents, or damages resulting from the use of this software.
+This implementation should not be used in production environments.
+
+All work, modifications, and security improvements are the sole responsibility of the author.

passman-dev/Caddyfile

@@ -0,0 +1,19 @@
+# HTTP site: redirect everything to HTTPS
+http://localhost {
+    redir https://{host}{uri} permanent
+}
+
+# HTTPS site
+https://localhost {
+    reverse_proxy web:80
+    tls internal
+
+    # Optional: security headers (defense-in-depth)
+    header {
+        X-Content-Type-Options "nosniff"
+        X-Frame-Options "DENY"
+        Referrer-Policy "no-referrer"
+    }
+}
+
+

passman-dev/Readme.md

@@ -0,0 +1,93 @@
+# Password Manager Security Application
+
+
+## Architecture Overview
+
+The application is deployed as a multi-container system.
+Each component has a clearly defined role and responsibility.
+All services are isolated and communicate only through Docker-managed networks.
+
+## Components
+
+### Web Application (PHP)
+
+The web service hosts the PHP-based password manager application.
+It is responsible for:
+- User authentication and session handling
+- Secure storage and retrieval of credentials
+- Input validation and output sanitization
+- Interaction with the database through restricted credentials
+
+The PHP application runs inside its own container and does not expose any ports directly to the host system.
+
+### Database (MySQL)
+
+The database service provides persistent storage for:
+- User accounts
+- Stored credentials
+- Application data
+
+Security improvements include:
+- Use of a dedicated database user with limited privileges
+- Separation of database credentials via environment variables
+- Isolation of the database service from direct external access
+
+
+### Reverse Proxy and HTTPS (Caddy)
+
+Caddy is used as a reverse proxy in front of the web application.
+It provides:
+- Automatic HTTP to HTTPS redirection
+- Internal TLS certificate generation
+- Secure termination of HTTPS connections
+- Optional security-related HTTP headers
+
+All external access to the application is handled exclusively by Caddy.
+
+
+## Deployment Instructions
+
+The deployment process is identical for Linux and Windows.
+The only requirement is a working Docker installation.
+
+
+### Prerequisites
+
+- Docker
+- Docker Compose (included in modern Docker installations)
+
+No additional software such as Apache, PHP, or MySQL is required on the host system.
+
+
+### Deployment on Linux
+
+1. Open a terminal.
+2. Navigate to the project directory containing `docker-compose.yml`.
+3. Run the following command:
+    ```bash
+    docker compose up -d --build
+    ```
+4. Wait until all containers are built and started.
+5. Access the application through your browser using: https://localhost
+
+### Deployment on Windows
+
+1. Install Docker Desktop for Windows.
+2. Ensure that WSL2 is enabled (Docker Desktop will guide you automatically).
+3. Open PowerShell or Command Prompt.
+4. Navigate to the project directory containing docker-compose.yml.
+5. Run the following command:
+    ```bash
+    docker compose up -d --build
+    ```
+6. Once the containers are running, open a browser and navigate to: https://localhost
+
+### Notes on Reproducibility
+
+The use of Docker ensures that:
+- The application behaves identically on all supported operating systems
+- No manual configuration of web servers or databases is required
+- Environment-specific issues are minimized
+
+This approach allows evaluators to focus on the security aspects of the application rather than deployment complexity.
+

passman-dev/db/init/01-create-pwd_mgr-db-withData.sql

@@ -22,6 +22,12 @@ CREATE TABLE IF NOT EXISTS `dummy` (
   `id` int(11) DEFAULT NULL
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
 
+-- Create a dedicated DB user for the web application (least privilege).
+-- Grant only the required privileges on the application database.
+CREATE USER IF NOT EXISTS 'passman_app'@'%' IDENTIFIED BY 'passman_app_pw';
+GRANT SELECT, INSERT, UPDATE, DELETE ON pwd_mgr.* TO 'passman_app'@'%';
+FLUSH PRIVILEGES;
+
 CREATE TABLE IF NOT EXISTS `login_users` (
   `id` int(11) NOT NULL AUTO_INCREMENT,
   `username` varchar(20) NOT NULL,
@@ -31,7 +37,7 @@ CREATE TABLE IF NOT EXISTS `login_users` (
 ) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
 
 INSERT INTO `login_users` (`id`, `username`, `password`) VALUES
-	(1, 'u1', '$2y$10$L18u5/PyVkDgsce/DsUOQu0sKhTzh854Euhog3cVb1W4YAfgRzY8W'); /* php -r 'echo password_hash("p1", PASSWORD_DEFAULT), PHP_EOL;' */
+	(1, 'u1', '$2y$10$L18u5/PyVkDgsce/DsUOQu0sKhTzh854Euhog3cVb1W4YAfgRzY8W'); -- php -r 'echo password_hash("p1", PASSWORD_DEFAULT), PHP_EOL;'
 
 CREATE TABLE IF NOT EXISTS `notes` (
   `notesid` int(11) NOT NULL AUTO_INCREMENT,

passman-dev/docker-compose.yml

@@ -2,18 +2,30 @@
 services:
   web:
     build: .
-    ports:
+    # ports:
-      - "80:80"
+    #   - "80:80"
     volumes:
       - ./php:/var/www/html
     environment:
       DB_HOST: db
-      DB_USER: root
-      DB_PASS: rootpass
       DB_NAME: pwd_mgr
+      DB_USER: passman_app
+      DB_PASS: passman_app_pw
     depends_on:
       - db
 
+  proxy:
+    image: caddy:2
+    ports:
+      - "80:80"
+      - "443:443"
+    volumes:
+      - ./Caddyfile:/etc/caddy/Caddyfile:ro
+      - caddy_data:/data
+      - caddy_config:/config
+    depends_on:
+      - web
+
   db:
     image: mariadb:11
     container_name: passman_db
@@ -30,4 +42,6 @@ services:
 
 volumes:
   dbdata:
+  caddy_data:
+  caddy_config:
 

passman-dev/php/passman/config.php

@@ -3,8 +3,8 @@
 // NOTE: In Docker, the DB host is the service name (e.g., "db"), not "localhost".
 
 $DB_HOST = getenv('DB_HOST') ?: 'db';
-$DB_USER = getenv('DB_USER') ?: 'root';
+$DB_USER = getenv('DB_USER') ?: 'passman_app';
-$DB_PASS = getenv('DB_PASS') ?: 'rootpass';
+$DB_PASS = getenv('DB_PASS') ?: 'passman_app_pw';
 $DB_NAME = getenv('DB_NAME') ?: 'pwd_mgr';
 
 // Create a DB connection.

passman-dev/php/passman/index.html

@@ -15,23 +15,23 @@
 	<br />
 	<ul>
 		<li>
-			<a href="http://localhost/passman/register.php">Registration Form</a>
+			<a href="/passman/register.php">Registration Form</a>
 		</li>
 		<br />
 		<li>
-			<a href="http://localhost/passman/login.php">Login Page</a>
+			<a href="/passman/login.php">Login Page</a>
 		</li>
 		<br />
 		<li>
-			<a href="http://localhost/passman/logout.php">Logout Page</a>
+			<a href="/passman/logout.php">Logout Page</a>
 		</li>
 		<br />
 		<li>
-			<a href="http://localhost/passman/dashboard.php">Dashboard</a> (display passwords for websites)
+			<a href="/passman/dashboard.php">Dashboard</a> (display passwords for websites)
 		</li>
 		<br />
 		<li>
-			<a href="http://localhost/passman/notes.php">Notes</a> (notes/comments/announcements)
+			<a href="/passman/notes.php">Notes</a> (notes/comments/announcements)
 		</li>
 		<br />
 	</ul>
@@ -41,18 +41,18 @@
 	<br />
 	<ul>
 		<li>
-			Test <a href="http://localhost/passman/test_hash.php">hashing</a> functions in PHP (server side)
+			Test <a href="/passman/test_hash.php">hashing</a> functions in PHP (server side)
 		</li>
 		<br />
 		<li>
-			Test <a href="http://localhost/passman/test_encrypt.php">encrypting/decrypting</a> functions in PHP (server side)
+			Test <a href="/passman/test_encrypt.php">encrypting/decrypting</a> functions in PHP (server side)
 		</li>
 		<br />
 	</ul>
 
 	<br />
 	&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Hacker's side (for using stealing cookies using XSS):
-	<a href="http://localhost/passman/xss">http://localhost/passman/xss</a>
+	<a href="/passman/xss">passman/xss</a>
 	<br />
 
 </body>

passman-dev/php/passman/test_encrypt.php

@@ -0,0 +1,84 @@
+<?php
+// Simple example of encrypting/decrypting data using a password
+
+function getPasswordHash_Bin($username, $password) {
+    $salt = hash('sha256', $username, true);	// Compute salt as the hash of the username (parameter 'true' computes hash in bin format, default is hex)
+    $saltedPwd = $salt . $password;				// Get a salted password by combining salt and password
+    $hashedPwd = hash('sha256', $saltedPwd, true);	// Hash the salted password using SHA-256
+    // Return the password hash and the salt
+    return [
+        'hash' => $hashedPwd,
+        'salt' => $salt
+    ];
+}
+
+function deriveEncryptionKey($username, $password) {
+    // Compute binary hash of salted-password (and salt) from username and password
+    $pwdHash = getPasswordHash_Bin($username, $password);
+
+    // Derive a secure key using PBKDF2
+    $iterations = 100000; // Number of iterations for PBKDF2
+    $keyLength = 32; // Key length = 32 bytes for AES-256
+    $key = hash_pbkdf2('sha256', $pwdHash['hash'], $pwdHash['salt'], $iterations, $keyLength, true); // Parameter 'true' computes hash_pbkdf2 in bin
+    return $key;
+}
+
+// Encrypt data using AES-256-GCM
+function encryptData($data, $key) {
+    $nonce = random_bytes(12); // 12 bytes for AES-GCM nonce
+    $cipher = "aes-256-gcm";
+
+    // Encrypt the data
+    $ciphertext = openssl_encrypt($data, $cipher, $key, OPENSSL_RAW_DATA, $nonce, $tag);
+
+    //echo "nonce: " . bin2hex($nonce) . "<br>";;
+    //echo "tag: " . bin2hex($tag) . "<br>";;
+
+    // Concatenate nonce, tag, and ciphertext for storage
+    $result = $nonce . $tag . $ciphertext;
+    return base64_encode($result); // Encode to make it suitable for storage or transmission
+}
+
+// Decrypt data using AES-256-GCM, extracting nonce, tag, and ciphertext from the concatenated string
+function decryptData($encryptedData, $key) {
+    $cipher = "aes-256-gcm";
+
+    // Decode the base64-encoded data
+    $encryptedData = base64_decode($encryptedData);
+
+    // Extract nonce (12 bytes), tag (16 bytes), and ciphertext
+    $nonce = substr($encryptedData, 0, 12);
+    $tag = substr($encryptedData, 12, 16);
+    $ciphertext = substr($encryptedData, 28);
+
+    // Decrypt the data
+    $decryptedData = openssl_decrypt($ciphertext, $cipher, $key, OPENSSL_RAW_DATA, $nonce, $tag);
+
+    return $decryptedData;
+}
+
+
+// Example Usage
+$username = "user123";
+$password = "securepassword";
+$dataToEncrypt = "Sensitive Data";
+
+// Derive a symmetric encryption/dec key by hashing the password (and username as the salt) using PBKDF2 algorithm
+$encryptionKey = deriveEncryptionKey($username, $password);
+
+// Encrypt the data
+$encrypted = encryptData($dataToEncrypt, $encryptionKey);
+
+// Decrypt the data
+$decrypted = decryptData($encrypted, $encryptionKey);
+
+// Display results
+echo "Original Data: $dataToEncrypt<br>";
+//echo "Encryption Key (in bin): " . $encryptionKey . "<br>";
+//echo "Encryption Key (in hex): " . bin2hex($encryptionKey) . "<br>";
+echo "Encrypted Data (in base64): " . $encrypted . "<br>";
+//echo "Encrypted Data (in bin): " . base64_decode($encrypted) . "<br>";
+//echo "Encrypted Data (in hex): " . bin2hex(base64_decode($encrypted)) . "<br>";
+echo "Decrypted Data: $decrypted<br>";
+
+?>

passman-dev/php/passman/test_hash.php

@@ -0,0 +1,46 @@
+<?php
+// Simple example of hashing password
+
+$username = "user123";
+$password = "securepassword";
+
+// Compute salt as the hash of the username
+$salt = hash('sha256', $username);
+
+// Get a salted password by combining salt and password
+$saltedPwd = $salt . $password;
+
+// Hash the salted password using SHA-256
+$hashedPwd = hash('sha256', $saltedPwd);
+
+// Display variables
+echo "Username: $username<br>";
+echo "Password: $password<br>";
+
+echo "Salt (computed as the username's hash): $salt<br>";
+echo "Salted password: $saltedPwd<br>";
+echo "Hash of salted password: $hashedPwd<br>";
+echo "<p>";
+
+
+// Same as above but using a function
+
+function getPasswordHash_Hex($username, $password) {
+    // Compute hash of salted-password (and salt) from username and password (in hex format)
+    $salt = hash('sha256', $username);	// Compute salt as the hash of the username
+    $saltedPwd = $salt . $password;		// Get a salted password by combining salt and password
+    $hashedPwd = hash('sha256', $saltedPwd);	// Hash the salted password using SHA-256
+    // Return the password hash and the salt
+    return [
+        'hash' => $hashedPwd,
+        'salt' => $salt
+    ];
+}
+
+// Example usage of function getPasswordHash
+$getHasedPwd = getPasswordHash_Hex($username, $password);
+// Display results
+echo "Salt (in hex) computed using function getPasswordHash_Hex: " . $getHasedPwd['salt'] . "<br>";
+echo "Hash (in hex) computed using function getPasswordHash_Hex: " . $getHasedPwd['hash'] . "<br>";
+
+?>