feat: connect via rcon

app/Services/AccessRequestApprover.php

@@ -0,0 +1,37 @@
+<?php
+
+namespace App\Services;
+
+use App\Enums\AccessRequestStatus;
+use App\Models\AccessRequests;
+use App\Models\User;
+use DomainException;
+use Illuminate\Support\Facades\DB;
+
+class AccessRequestApprover
+{
+    public function __construct(
+        private readonly RconAccessGrantor $rconAccessGrantor,
+    ) {}
+
+    public function approve(AccessRequests $accessRequest, ?User $reviewer = null): string
+    {
+        $accessRequest->refresh();
+
+        if ($accessRequest->status !== AccessRequestStatus::PENDING) {
+            throw new DomainException('Only pending access requests can be accepted.');
+        }
+
+        $output = $this->rconAccessGrantor->grant($accessRequest);
+
+        DB::transaction(function () use ($accessRequest, $reviewer): void {
+            $accessRequest->forceFill([
+                'status' => AccessRequestStatus::ACCEPTED,
+                'reviewed_by' => $reviewer?->getKey(),
+                'reviewed_at' => now(),
+            ])->save();
+        });
+
+        return $output;
+    }
+}

app/Services/MinecraftRconClient.php

@@ -0,0 +1,162 @@
+<?php
+
+namespace App\Services;
+
+use RuntimeException;
+
+class MinecraftRconClient
+{
+    private const AUTH_PACKET_TYPE = 3;
+
+    private const COMMAND_PACKET_TYPE = 2;
+
+    /**
+     * @var resource|null
+     */
+    private $socket = null;
+
+    private int $requestId = 1;
+
+    public function command(string $command): string
+    {
+        $this->connect();
+
+        try {
+            $this->authenticate();
+
+            $requestId = $this->nextRequestId();
+            $this->writePacket($requestId, self::COMMAND_PACKET_TYPE, $command);
+
+            $response = $this->readPacket();
+
+            if ($response['id'] !== $requestId) {
+                throw new RuntimeException('Unexpected RCON response id.');
+            }
+
+            return $response['body'];
+        } finally {
+            $this->disconnect();
+        }
+    }
+
+    private function connect(): void
+    {
+        $host = config('rcon.host');
+        $port = (int) config('rcon.port');
+        $timeout = (float) config('rcon.timeout');
+
+        if (blank($host)) {
+            throw new RuntimeException('MC_RCON_HOST is not configured.');
+        }
+
+        $socket = @stream_socket_client(
+            "tcp://{$host}:{$port}",
+            $errorCode,
+            $errorMessage,
+            $timeout,
+        );
+
+        if ($socket === false) {
+            throw new RuntimeException("Unable to connect to Minecraft RCON: {$errorMessage} ({$errorCode}).");
+        }
+
+        $this->socket = $socket;
+        $seconds = (int) floor($timeout);
+        $microseconds = (int) (($timeout - $seconds) * 1_000_000);
+
+        stream_set_timeout($this->socket, $seconds, $microseconds);
+    }
+
+    private function authenticate(): void
+    {
+        $password = config('rcon.password');
+
+        if (blank($password)) {
+            throw new RuntimeException('MC_RCON_PASSWORD is not configured.');
+        }
+
+        $requestId = $this->nextRequestId();
+        $this->writePacket($requestId, self::AUTH_PACKET_TYPE, (string) $password);
+
+        do {
+            $response = $this->readPacket();
+        } while ($response['type'] !== self::COMMAND_PACKET_TYPE);
+
+        if ($response['id'] === -1 || $response['id'] !== $requestId) {
+            throw new RuntimeException('Minecraft RCON authentication failed.');
+        }
+    }
+
+    private function disconnect(): void
+    {
+        if (is_resource($this->socket)) {
+            fclose($this->socket);
+        }
+
+        $this->socket = null;
+    }
+
+    private function nextRequestId(): int
+    {
+        return $this->requestId++;
+    }
+
+    private function writePacket(int $requestId, int $type, string $body): void
+    {
+        $payload = pack('VV', $requestId, $type).$body."\x00\x00";
+        $packet = pack('V', strlen($payload)).$payload;
+        $bytesWritten = 0;
+
+        while ($bytesWritten < strlen($packet)) {
+            $written = fwrite($this->socket, substr($packet, $bytesWritten));
+
+            if ($written === false || $written === 0) {
+                throw new RuntimeException('Unable to write RCON packet.');
+            }
+
+            $bytesWritten += $written;
+        }
+    }
+
+    /**
+     * @return array{id: int, type: int, body: string}
+     */
+    private function readPacket(): array
+    {
+        $sizeData = $this->readBytes(4);
+        $size = unpack('V', $sizeData)[1];
+
+        if ($size < 10) {
+            throw new RuntimeException('Invalid RCON packet size.');
+        }
+
+        $packet = $this->readBytes($size);
+        $header = unpack('Vid/Vtype', substr($packet, 0, 8));
+        $id = $header['id'] >= 0x80000000
+            ? $header['id'] - 0x100000000
+            : $header['id'];
+
+        return [
+            'id' => $id,
+            'type' => $header['type'],
+            'body' => substr($packet, 8, -2),
+        ];
+    }
+
+    private function readBytes(int $length): string
+    {
+        $data = '';
+
+        while (strlen($data) < $length) {
+            $chunk = fread($this->socket, $length - strlen($data));
+
+            if ($chunk === false || $chunk === '') {
+                throw new RuntimeException('Unable to read RCON packet.');
+            }
+
+            $data .= $chunk;
+        }
+
+        return $data;
+    }
+}

app/Services/RconAccessGrantor.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace App\Services;
+
+use App\Models\AccessRequests;
+
+class RconAccessGrantor
+{
+    public function __construct(
+        private readonly MinecraftRconClient $rconClient,
+    ) {}
+
+    public function grant(AccessRequests $accessRequest): string
+    {
+        return $this->rconClient->command($this->commandFor($accessRequest->game_username));
+    }
+
+    private function commandFor(string $gameUsername): string
+    {
+        $accessCommand = (string) config('rcon.access_command', 'whitelist add {username}');
+
+        if (! str_contains($accessCommand, '{username}')) {
+            $accessCommand = trim($accessCommand).' {username}';
+        }
+
+        return str_replace('{username}', $gameUsername, $accessCommand);
+    }
+}