Added: end-to-end encryption support (#5)

capcom6 · web-flow · commit ee8390e39f5f · 2024-01-31T08:40:53.000+07:00
* Added: encryption support
diff --git a/README.md b/README.md
@@ -17,7 +17,7 @@ composer require capcom6/android-sms-gateway
 
 ## Usage
 
-Here is a simple example of how to send a message using the client:
+Here is a simple example of how to send a message using the library:
 
 
 ```php
@@ -26,33 +26,43 @@ Here is a simple example of how to send a message using the client:
 require 'vendor/autoload.php';
 
 use AndroidSmsGateway\Client;
+use AndroidSmsGateway\Encryptor;
 use AndroidSmsGateway\Domain\Message;
 
 $login = 'your_login';
 $password = 'your_password';
 
 $client = new Client($login, $password);
+// or
+// $encryptor = new Encryptor('your_passphrase');
+// $client = new Client($login, $password, Client::DEFAULT_URL, $httpClient, $encryptor);
 
 $message = new Message('Your message text here.', ['+1234567890']);
 
 try {
     $messageState = $client->Send($message);
-    echo "Message sent with ID: " . $messageState->ID();
+    echo "Message sent with ID: " . $messageState->ID() . PHP_EOL;
 } catch (Exception $e) {
-    echo "Error sending message: " . $e->getMessage();
+    echo "Error sending message: " . $e->getMessage() . PHP_EOL;
+    die(1);
 }
 
 try {
     $messageState = $client->GetState($messageState->ID());
-    echo "Message state: " . $messageState->State();
+    echo "Message state: " . $messageState->State() . PHP_EOL;
 } catch (Exception $e) {
-    echo "Error getting message state: " . $e->getMessage();
+    echo "Error getting message state: " . $e->getMessage() . PHP_EOL;
+    die(1);
 }
 ```
 
-## Methods
+## Client
 
-The `Client` class provides the following methods:
+The `Client` is used for sending SMS messages in plain text, but can also be used for sending encrypted messages by providing an `Encryptor`.
+
+### Methods
+
+The `Client` class has the following methods:
 
 * `Send(Message $message)`: Send a new SMS message.
 * `GetState(string $id)`: Retrieve the state of a previously sent message by its ID.
diff --git a/src/Client.php b/src/Client.php
@@ -19,6 +19,7 @@ class Client {
     protected string $baseUrl;
 
     protected HttpClient $client;
+    protected ?Encryptor $encryptor;
 
     protected RequestFactoryInterface $requestFactory;
     protected StreamFactoryInterface $streamFactory;
@@ -27,11 +28,13 @@ public function __construct(
         string $login,
         string $password,
         string $serverUrl = self::DEFAULT_URL,
-        ?HttpClient $client = null
+        ?HttpClient $client = null,
+        ?Encryptor $encryptor = null
     ) {
         $this->basicAuth = base64_encode($login . ':' . $password);
         $this->baseUrl = $serverUrl;
         $this->client = $client ?? HttpClientDiscovery::find();
+        $this->encryptor = $encryptor;
 
         $this->requestFactory = Psr17FactoryDiscovery::findRequestFactory();
         $this->streamFactory = Psr17FactoryDiscovery::findStreamFactory();
@@ -40,6 +43,10 @@ public function __construct(
     public function Send(Message $message): MessageState {
         $path = '/message';
 
+        if (isset($this->encryptor)) {
+            $message = $message->Encrypt($this->encryptor);
+        }
+
         $response = $this->sendRequest(
             'POST',
             $path,
@@ -49,7 +56,13 @@ public function Send(Message $message): MessageState {
             throw new \RuntimeException('Invalid response');
         }
 
-        return MessageState::FromObject($response);
+        $state = MessageState::FromObject($response);
+
+        if (isset($this->encryptor)) {
+            $state = $state->Decrypt($this->encryptor);
+        }
+
+        return $state;
     }
 
     public function GetState(string $id): MessageState {
@@ -63,7 +76,13 @@ public function GetState(string $id): MessageState {
             throw new \RuntimeException('Invalid response');
         }
 
-        return MessageState::FromObject($response);
+        $state = MessageState::FromObject($response);
+
+        if (isset($this->encryptor)) {
+            $state = $state->Decrypt($this->encryptor);
+        }
+
+        return $state;
     }
 
     /**
diff --git a/src/Domain/Message.php b/src/Domain/Message.php
@@ -2,6 +2,7 @@
 
 namespace AndroidSmsGateway\Domain;
 
+use AndroidSmsGateway\Encryptor;
 use AndroidSmsGateway\Interfaces\SerializableInterface;
 
 /**
@@ -30,6 +31,10 @@ class Message implements SerializableInterface {
      * Request delivery report, `true` by default
      */
     private bool $withDeliveryReport;
+    /**
+     * Is message and phones encrypted, `false` by default
+     */
+    private bool $isEncrypted = false;
     /**
      * Phone numbers in E164 format
      * @var array<string>
@@ -39,13 +44,35 @@ class Message implements SerializableInterface {
     /**
      * @param array<string> $phoneNumbers
      */
-    public function __construct(string $message, array $phoneNumbers, ?string $id = null, ?int $ttl = null, ?int $simNumber = null, bool $withDeliveryReport = true) {
+    public function __construct(
+        string $message,
+        array $phoneNumbers,
+        ?string $id = null,
+        ?int $ttl = null,
+        ?int $simNumber = null,
+        bool $withDeliveryReport = true
+    ) {
         $this->id = $id;
         $this->message = $message;
         $this->ttl = $ttl;
         $this->simNumber = $simNumber;
         $this->withDeliveryReport = $withDeliveryReport;
         $this->phoneNumbers = $phoneNumbers;
+        $this->isEncrypted = false;
+    }
+
+    public function Encrypt(Encryptor $encryptor): self {
+        if ($this->isEncrypted) {
+            return $this;
+        }
+
+        $this->isEncrypted = true;
+        $this->message = $encryptor->Encrypt($this->message);
+        $this->phoneNumbers = array_map(
+            fn(string $phoneNumber) => $encryptor->Encrypt($phoneNumber),
+            $this->phoneNumbers
+        );
+        return $this;
     }
 
     public function ToObject(): object {
@@ -55,6 +82,7 @@ public function ToObject(): object {
             'ttl' => $this->ttl,
             'simNumber' => $this->simNumber,
             'withDeliveryReport' => $this->withDeliveryReport,
+            'isEncrypted' => $this->isEncrypted,
             'phoneNumbers' => $this->phoneNumbers
         ];
     }
diff --git a/src/Domain/MessageState.php b/src/Domain/MessageState.php
@@ -2,6 +2,7 @@
 
 namespace AndroidSmsGateway\Domain;
 
+use AndroidSmsGateway\Encryptor;
 use AndroidSmsGateway\Enums\ProcessState;
 
 /**
@@ -24,38 +25,96 @@ class MessageState {
      */
     private array $recipients;
 
+    /**
+     * Is message and phones hashed
+     * @var bool
+     */
+    private bool $isHashed;
+
+    /**
+     * Is message and phones encrypted
+     * @var bool
+     */
+    private bool $isEncrypted;
+
     /**
      * @param array<RecipientState> $recipients
      */
-    public function __construct(string $id, ProcessState $state, array $recipients) {
+    public function __construct(
+        string $id,
+        ProcessState $state,
+        array $recipients,
+        bool $isHashed = false,
+        bool $isEncrypted = false
+    ) {
         $this->id = $id;
         $this->state = $state;
         $this->recipients = $recipients;
+        $this->isHashed = $isHashed;
+        $this->isEncrypted = $isEncrypted;
     }
 
+    /**
+     * Get message ID
+     * @return string
+     */
     public function ID(): string {
         return $this->id;
     }
 
+    /**
+     * Get message state
+     * @return ProcessState
+     */
     public function State(): ProcessState {
         return $this->state;
     }
 
     /**
+     * Is message and phones hashed
+     * @return bool
+     */
+    public function IsHashed(): bool {
+        return $this->isHashed;
+    }
+
+    /**
+     * Get recipient states
      * @return array<RecipientState>
      */
     public function Recipients(): array {
         return $this->recipients;
     }
 
+    public function Decrypt(Encryptor $encryptor): self {
+        if ($this->isHashed) {
+            return $this;
+        }
+
+        if (!$this->isEncrypted) {
+            return $this;
+        }
+
+        $this->recipients = array_map(
+            static fn(RecipientState $recipient) => $recipient->Decrypt($encryptor),
+            $this->recipients
+        );
+
+        $this->isEncrypted = false;
+
+        return $this;
+    }
+
     public static function FromObject(object $obj): self {
         return new self(
             $obj->id,
             ProcessState::FromValue($obj->state),
             array_map(
                 static fn($obj) => RecipientState::FromObject($obj),
                 $obj->recipients
-            )
+            ),
+            $obj->isHashed ?? false,
+            $obj->isEncrypted ?? false
         );
     }
 }
diff --git a/src/Domain/RecipientState.php b/src/Domain/RecipientState.php
@@ -2,6 +2,7 @@
 
 namespace AndroidSmsGateway\Domain;
 
+use AndroidSmsGateway\Encryptor;
 use AndroidSmsGateway\Enums\ProcessState;
 
 /**
@@ -39,6 +40,12 @@ public function Error(): ?string {
         return $this->error;
     }
 
+    public function Decrypt(Encryptor $encryptor): self {
+        $this->phoneNumber = $encryptor->Decrypt($this->phoneNumber);
+
+        return $this;
+    }
+
     public static function FromObject(object $obj): self {
         return new self(
             $obj->phoneNumber,
diff --git a/src/Encryptor.php b/src/Encryptor.php
@@ -0,0 +1,77 @@
+<?php
+
+namespace AndroidSmsGateway;
+
+class Encryptor {
+    protected string $passphrase;
+    protected int $iterationCount;
+
+    /**
+     * Encryptor constructor.
+     * @param string $passphrase Passphrase to use for encryption
+     * @param int $iterationCount Iteration count
+     */
+    public function __construct(
+        string $passphrase,
+        int $iterationCount = 75000
+    ) {
+        $this->passphrase = $passphrase;
+        $this->iterationCount = $iterationCount;
+    }
+
+    public function Encrypt(string $data): string {
+        $salt = $this->generateSalt();
+        $secretKey = $this->generateSecretKeyFromPassphrase($this->passphrase, $salt, 32, $this->iterationCount);
+
+        return sprintf(
+            '$aes-256-cbc/pbkdf2-sha1$i=%d$%s$%s',
+            $this->iterationCount,
+            base64_encode($salt),
+            openssl_encrypt($data, 'aes-256-cbc', $secretKey, 0, $salt)
+        );
+    }
+
+    public function Decrypt(string $data): string {
+        list($_, $algo, $paramsStr, $saltBase64, $encryptedBase64) = explode('$', $data);
+
+        if ($algo !== 'aes-256-cbc/pbkdf2-sha1') {
+            throw new \RuntimeException('Unsupported algorithm');
+        }
+
+        $params = $this->parseParams($paramsStr);
+        if (empty($params['i'])) {
+            throw new \RuntimeException('Missing iteration count');
+        }
+
+        $salt = base64_decode($saltBase64);
+        $secretKey = $this->generateSecretKeyFromPassphrase($this->passphrase, $salt, 32, intval($params['i']));
+
+        return openssl_decrypt($encryptedBase64, 'aes-256-cbc', $secretKey, 0, $salt);
+    }
+
+    protected function generateSalt(int $size = 16): string {
+        return random_bytes($size);
+    }
+
+    protected function generateSecretKeyFromPassphrase(
+        string $passphrase,
+        string $salt,
+        int $keyLength = 32,
+        int $iterationCount = 75000
+    ): string {
+        return hash_pbkdf2('sha1', $passphrase, $salt, $iterationCount, $keyLength, true);
+    }
+
+    /**
+     * @return array<string, string>
+     */
+    protected function parseParams(string $params): array {
+        $keyValuePairs = explode(',', $params);
+        $result = [];
+        foreach ($keyValuePairs as $pair) {
+            list($key, $value) = explode('=', $pair, 2);
+            $result[$key] = $value;
+        }
+        return $result;
+    }
+}
diff --git a/tests/Domain/MessageTest.php b/tests/Domain/MessageTest.php
