<?php
/*
 +-------------------------------------------------------------------------+
 | Copyright (C) 2004-2026 The Cacti Group                                 |
 |                                                                         |
 | This program is free software; you can redistribute it and/or           |
 | modify it under the terms of the GNU General Public License             |
 | as published by the Free Software Foundation; either version 2          |
 | of the License, or (at your option) any later version.                  |
 |                                                                         |
 | This program is distributed in the hope that it will be useful,         |
 | but WITHOUT ANY WARRANTY; without even the implied warranty of          |
 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the           |
 | GNU General Public License for more details.                            |
 +-------------------------------------------------------------------------+
 | Cacti: The Complete RRDTool-based Graphing Solution                     |
 +-------------------------------------------------------------------------+
 | This code is designed, written, and maintained by the Cacti Group. See  |
 | about.php and/or the AUTHORS file for specific developer information.   |
 +-------------------------------------------------------------------------+
 | http://www.cacti.net/                                                   |
 +-------------------------------------------------------------------------+
*/

use phpseclib4\Crypt\RSA;

/**
 * Handles a single client connection for its entire lifetime: performs the RSA
 * public-key handshake, then authenticates, decrypts, and dispatches each request
 * (RRDtool commands, custom commands, and removespikes) to its handler, encrypting
 * and writing back every response until the client disconnects or times out.
 *
 * @param resource|\Socket $socket_client
 *
 * @return void
 */
function interact($socket_client) {
	/*
		Clients using the default port are only allowed to talk to RRDtool directly.
		By using IPC this child process will interact with the main process.
	*/
	global $rrdcached_pid, $rrdp_config, $ipc_socket_parent, $rrdtool_cmds, $rrdtool_custom_cmds;
	global $rrdtool_msr_cmds, $rrdp_status, $rrdtool_env_vars, $rrdp_client_cnn_params;
	global $encryption;

	if ($rrdcached_pid) {
		putenv('RRDCACHED_ADDRESS=unix:' . realpath('') . '/run/rrdcached.sock');
	}

	// switch into the rra directory
	chdir($rrdp_config['path_rra']);

	set_time_limit(0);

	$encryption           = true;
	$rrdp_status_backup   = $rrdp_status;
	$rrdtool_process      = false;
	$rrdtool_pipes        = [];
	$client_authenticated = false;
	$client_public_key    = '';
	$end_of_packet        = "_EOP_\r\n";
	$end_of_sequence      = "_EOT_\r\n";

	$tv_sec = $rrdp_config['remote_cnn_timeout'];

	// avoid zombies
	socket_set_option($socket_client,SOL_SOCKET, SO_RCVTIMEO, ['sec'=>600, 'usec'=>0]);
	socket_set_block($socket_client);
	socket_set_block($ipc_socket_parent);

	$real_client_resource_id = rrdp_system__get_resource_id($socket_client);
	$ipc_parent_resource_id  = rrdp_system__get_resource_id($ipc_socket_parent);

	$input = '';

	while (1) {
		// setup clients listening to socket for reading
		$read    = [];
		$read[0] = $socket_client;
		$read[1] = $ipc_socket_parent;

		$ready = socket_select($read, $write, $except, $tv_sec);

		switch ($err = socket_last_error()) {
			case 0:
				socket_clear_error();

				break;
			default:
				__logging(LOGGING_LOCATION_BUFFERED, 'Critical error occurred: ' . $err, 'IPC', SEVERITY_LEVEL_CRITICAL);

				break 2;
		}

		if ($ready > 0) {
			foreach ($read as $read_socket_index => $read_socket) {
				$socket_resource_id = rrdp_system__get_resource_id($read_socket);

				if ($socket_resource_id == $real_client_resource_id) {
					// RRDtool client is talking to us

					while (1) {
						$recv = @socket_read($read_socket, 100000, PHP_BINARY_READ);

						if ($recv === false) {
							// timeout
							rrdp_system__socket_write($socket_client, (($client_authenticated) ? encrypt(RRD_ERROR . 'Timeout', $client_public_key) : RRD_ERROR . 'Timeout') . $end_of_sequence);
							__logging(LOGGING_LOCATION_BUFFERED, 'Client connection timeout detected', 'IPC', SEVERITY_LEVEL_WARNING);
							$rrdp_status['status'] = 'CLOSEDOWN_BY_TIMEOUT';

							break 3;
						}

						if ($recv === '') {
							// socket session dropped by client
							__logging(LOGGING_LOCATION_BUFFERED, 'Connection dropped by client', 'IPC', SEVERITY_LEVEL_NOTIFICATION);
							$rrdp_status['status'] = 'CLOSEDOWN_BY_CLIENT_DROP';

							break 3;
						} else {
							$input .= $recv;
							$max_input_size = $client_authenticated ? RRDP_MAX_REQUEST_SIZE : RRDP_MAX_KEY_SIZE;

							if (strpos($input, $end_of_sequence) !== false) { // end of one or more transactions detected
								rrdp_system__count('bytes_received', rrdp_system__calc_bytes($input));

								$transactions = explode($end_of_sequence, $input);
								$input        = array_pop($transactions);

								foreach ($transactions as $transaction) {
									if (strlen($transaction) > $max_input_size) {
										rrdp_system__socket_write($socket_client, (($client_authenticated) ? encrypt(RRD_ERROR . ' Request too large', $client_public_key) : RRD_ERROR . ' Request too large') . $end_of_sequence);
										__logging(LOGGING_LOCATION_BUFFERED, 'Client request exceeded the maximum frame size', 'IPC', SEVERITY_LEVEL_WARNING);
										$rrdp_status['status'] = 'CLOSEDOWN_BY_VIOLATION';

										break 4;
									}

									if (!$client_authenticated) {
										if (strpos($transaction, '-----BEGIN PUBLIC KEY-----') === false) {
											// authentication failed !!!
											rrdp_system__socket_write($socket_client, 'Authentication failed' . $end_of_sequence);
											__logging(LOGGING_LOCATION_BUFFERED, 'Client Authentication failed by invalid key format', 'IPC', SEVERITY_LEVEL_ERROR);
											$rrdp_status['status'] = 'CLOSEDOWN_BY_CLIENT_AUTH';

											break 4;
										} else {
											$client_public_key = $transaction;
											socket_getpeername($socket_client, $ip);
											$rsa_finger_print = isset($rrdp_config['remote_clients'][$ip]) ? $rrdp_config['remote_clients'][$ip] : 'unknown';

											try {
												$public_key         = RSA::loadPublicKey($client_public_key);
												$client_fingerprint = $public_key->getFingerprint('md5');
											} catch (Throwable $e) {
												$client_fingerprint = false;
											}

											if ($client_fingerprint !== false && hash_equals(strtolower($rsa_finger_print), strtolower($client_fingerprint))) {
												// registered public key has been received
												$client_authenticated = true;
												// send out proxy's public key
												rrdp_system__socket_write($socket_client, $rrdp_config['encryption']['public_key'] . $end_of_sequence);
												__logging(LOGGING_LOCATION_BUFFERED, 'Client Authentication successful', 'IPC', SEVERITY_LEVEL_DEBUG);

												continue;
											} else {
												// authentication failed !!!
												rrdp_system__socket_write($socket_client, 'Authentication failed' . $end_of_sequence);
												__logging(LOGGING_LOCATION_BUFFERED, 'Client Authentication failed by invalid public key', 'IPC', SEVERITY_LEVEL_ERROR);
												$rrdp_status['status'] = 'CLOSEDOWN_BY_CLIENT_AUTH';

												break 4;
											}
										}
									} else {
										$transaction = decrypt($transaction);

										if ($transaction === false) {
											rrdp_system__socket_write($socket_client, 'Decryption error' . $end_of_sequence);
											__logging(LOGGING_LOCATION_BUFFERED, 'Client message decryption failed.', 'IPC', SEVERITY_LEVEL_ERROR);
											$rrdp_status['status'] = 'CLOSEDOWN_BY_DECRYPTION';

											break 4;
										}

										if (strpos($transaction, "\x1f\x8b") === 0) {
											$transaction = gzdecode($transaction, RRDP_MAX_DECOMPRESSED_REQUEST_SIZE);

											if ($transaction === false) {
												rrdp_system__socket_write($socket_client, encrypt(RRD_ERROR . ' Invalid compressed request', $client_public_key) . $end_of_sequence);
												$rrdp_status['status'] = 'CLOSEDOWN_BY_VIOLATION';

												break 4;
											}
										}

										// take care of invalid blanks
										$transaction = trim($transaction);

										if (strpos($transaction, ' ') != false) {
											$options     = explode(' ', $transaction, 2);
											$cmd         = $options[0];
											$cmd_options = $options[1];
										} else {
											$cmd         = $transaction;
											$cmd_options = '';
										}

										// try to react as similar as possible
										if (!$cmd) {
											$cmd = 'info';
										}

										__logging(LOGGING_LOCATION_BUFFERED, 'REQUEST: ' . $cmd . ' ' . $cmd_options , 'IPC', SEVERITY_LEVEL_DEBUG);

										if (in_array($cmd, $rrdtool_cmds, true) === true) {
											if (rrdp_command_has_unsafe_path($cmd_options)) {
												rrdp_system__socket_write($socket_client, encrypt(RRD_ERROR . ' Unsafe path or command framing', $client_public_key) . $end_of_sequence);
												rrdp_system__count('queries_rrdtool_invalid');

												continue;
											}

											$resolved_cmd_options = rrdp_resolve_command_paths($cmd, $cmd_options);

											if ($resolved_cmd_options === false) {
												rrdp_system__socket_write($socket_client, encrypt(RRD_ERROR . ' Unsafe path or command framing', $client_public_key) . $end_of_sequence);
												rrdp_system__count('queries_rrdtool_invalid');

												continue;
											}

											$cmd_options = $resolved_cmd_options;

											rrdp_system__count('queries_rrdtool_total');

											// open a persistent RRDtool pipe only on demand
											if ($rrdtool_process === false) {
												$rrdtool_process_pipes	 = rrdtool_pipe_init($rrdp_config);

												if ($rrdtool_process_pipes === false) {
													rrdp_system__count('rrd_pipe_broken');
													rrdp_system__socket_write($socket_client, encrypt(RRD_ERROR . ' RRDTOOL_PIPE_UNAVAILABLE', $client_public_key) . $end_of_sequence);

													continue;
												}

												$rrdtool_process = $rrdtool_process_pipes[0];
												$rrdtool_pipes   = $rrdtool_process_pipes[1];
											}

											$auto_compression = in_array($cmd, ['xport', 'fetch', 'dump', 'graph', 'graphv', 'updatev ', 'info'], true) && strpos($cmd_options, '--imgformat=PNG') === false;
											$rrd_exec_status  = rrdtool_pipe_execute($cmd . ' ' . $cmd_options . "\r\n", $rrdtool_pipes, $socket_client, $client_public_key, $auto_compression, false, $end_of_sequence);

											if ($rrd_exec_status === true) {
												rrdp_system__count('queries_rrdtool_valid');

												// update local cache by valid RRDtool commands for MSR
												if (__sizeof($rrdp_config['remote_proxies']) > 0 && in_array($cmd , $rrdtool_msr_cmds, true) === true) {
													__logging(LOGGING_LOCATION_BUFFERED, 'MSR: ' . $cmd . ' ' . $cmd_options , 'MSR', SEVERITY_LEVEL_DEBUG);
													[$mtime,$time] = explode(' ',microtime());

													$mtime  = (float) $mtime;
													$time   = (int) $time;
													$offset = $time % 10;
													$block  = $time - $offset + 10;

													$rrdp_status['msr_commands'][$block][$offset + $mtime . '_' . $socket_resource_id] = $cmd . ' ' . $cmd_options;

													if (__sizeof($rrdp_status['msr_commands']) > 1 || $time >= $block) {
														$msr_block = key($rrdp_status['msr_commands']);

														$msr_message['type'] = 'msr';

														$msr_message['msr_commands'][$msr_block] = $rrdp_status['msr_commands'][$msr_block];

														if (@socket_write($ipc_socket_parent, serialize($msr_message) . "\r\n")) {
															unset($rrdp_status['msr_commands'][$msr_block]);
															unset($msr_message);
															$rrdp_status = $rrdp_status_backup;
															usleep(10000);
														}
													}
												}
											} elseif ($rrd_exec_status === null) {
												// RRDtool pipe broken
												rrdp_system__count('rrd_pipe_broken');
												rrdp_system__socket_write($socket_client, encrypt(RRD_ERROR . 'RRDTOOL_PIPE_BROKEN', $client_public_key) . $end_of_sequence);
												rrdtool_pipe_close($rrdtool_process);
												$rrdtool_process = false;
											} else {
												// client tried to execute an invalid or unsupported RRDtool command
												rrdp_system__count('queries_rrdtool_invalid');
											}
										} elseif (in_array($cmd, ['exit', 'quit', 'shutdown'], true) === true) {
											// client wants to quit on a regular basis
											$rrdp_status['status'] = 'CLOSEDOWN_BY_CLIENT_CMD';

											break 4;
										} elseif (in_array($cmd, $rrdtool_custom_cmds, true)) {
											$rrdp_exec_status = false;
											$options          = explode(' ', $cmd_options);

											switch ($cmd) {
												case 'setenv':
													if (__sizeof($options) >= 2 && in_array($options[0], $rrdtool_env_vars, true)) {
														$enviro_var   = array_shift($options);
														$enviro_value = str_replace(["\0", "\r", "\n"], '', implode(' ', $options));
														putenv($enviro_var . '=' . $enviro_value);
														rrdp_system__socket_write($socket_client, encrypt(RRD_OK, $client_public_key) . $end_of_sequence);
														__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . RRD_OK, 'IPC', SEVERITY_LEVEL_DEBUG);
													} else {
														rrdp_system__socket_write($socket_client, encrypt(RRD_ERROR . ' % setenv <name> <value>', $client_public_key) . $end_of_sequence);
														__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . RRD_ERROR, 'IPC', SEVERITY_LEVEL_DEBUG);
													}

													break;
												case 'getenv':
													if (__sizeof($options) == 1 && in_array($options[0], $rrdtool_env_vars, true)) {
														$output = getenv($options[0]);
														rrdp_system__socket_write($socket_client, encrypt($output . "\n" . RRD_OK, $client_public_key) . $end_of_sequence);
														__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . $output . "\n" . RRD_OK, 'IPC', SEVERITY_LEVEL_DEBUG);
													} else {
														rrdp_system__socket_write($socket_client, encrypt(RRD_ERROR . ' % getenv <name>', $client_public_key) . $end_of_sequence);
														__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . RRD_ERROR, 'IPC', SEVERITY_LEVEL_DEBUG);
													}

													break;
												case 'setcnn':
													if (__sizeof($options) == 2 && in_array($options[0], $rrdp_client_cnn_params, true)) {
														if ($options[0] == 'timeout') {
															if (in_array($options[1], ['null', 'off', 'disabled', '-1'], true)) {
																$tv_sec = null;
																rrdp_system__socket_write($socket_client, encrypt("% Timeout disabled.\n" . RRD_OK, $client_public_key) . $end_of_sequence);
																__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . RRD_OK, 'IPC', SEVERITY_LEVEL_DEBUG);
															} elseif (is_numeric($options[1])) {
																$tv_sec = abs($options[1]);
																rrdp_system__socket_write($socket_client, encrypt('% Timeout ' . $tv_sec . "s.\n" . RRD_OK, $client_public_key) . $end_of_sequence);
																__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . RRD_OK, 'IPC', SEVERITY_LEVEL_DEBUG);
															} else {
																rrdp_system__socket_write($socket_client, encrypt(RRD_ERROR . ' % Out of range.', $client_public_key) . $end_of_sequence);
																__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . RRD_ERROR, 'IPC', SEVERITY_LEVEL_DEBUG);
															}
														}
													} else {
														rrdp_system__socket_write($socket_client, encrypt(RRD_ERROR . ' % setcnn <parameter> <value>', $client_public_key) . $end_of_sequence);
														__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . RRD_ERROR, 'IPC', SEVERITY_LEVEL_DEBUG);
													}

													break;
												case 'fc-list':
													$output = shell_exec('fc-list');
													rrdp_system__socket_write($socket_client, encrypt($output . "\n" . RRD_OK, $client_public_key) . $end_of_sequence);
													__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . RRD_OK, 'IPC', SEVERITY_LEVEL_DEBUG);

													break;
												case 'rrd-list':
													// scan RRA folder
													clearstatcache();
													$buffer            = '';
													$rra_path_absolute = realpath($rrdp_config['path_rra']);

													if ($rra_path_absolute === false) {
														rrdp_system__socket_write($socket_client, encrypt(RRD_ERROR . ' RRA path is unavailable', $client_public_key) . $end_of_sequence);

														break;
													}

													$dir_iterator = new RecursiveDirectoryIterator($rra_path_absolute);
													$iterator     = new RecursiveIteratorIterator($dir_iterator, RecursiveIteratorIterator::SELF_FIRST);

													foreach ($iterator as $file) {
														$resolved_path = realpath($file->getPathname());

														if ($resolved_path !== false
															&& rrdp_path_is_within($resolved_path, $rra_path_absolute)
															&& str_ends_with(strtolower($resolved_path), '.rrd')) {
															$buffer .= ltrim(substr($resolved_path, strlen($rra_path_absolute)), DIRECTORY_SEPARATOR) . ',' . $file->getSize() . ',' . $file->getMTime() . "\r\n";
														}
													}

													$buffer .= RRD_OK;

													$buffer_length     = strlen($buffer);
													$buffer            = gzencode($buffer,1);
													$buffer_length_new = strlen($buffer);

													rrdp_system__socket_write($read_socket, encrypt($buffer, $client_public_key) . $end_of_sequence);
													__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . RRD_OK . ', payload: ' . $buffer_length_new . ' Bytes, compression: on , ratio: ' . round(($buffer_length / $buffer_length_new),2) . ' , packets: 1', 'IPC', SEVERITY_LEVEL_DEBUG);

													break;
												case 'filemtime':
													$path = __sizeof($options) === 1 ? rrdp_resolve_rra_path($options[0]) : false;

													$rrdp_exec_return = $path !== false ? filemtime($path) : false;

													rrdp_system__socket_write($socket_client, encrypt($rrdp_exec_return . "\r\n" . RRD_OK, $client_public_key) . $end_of_sequence);
													__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . $rrdp_exec_return . "\r\n" . RRD_OK, 'IPC', SEVERITY_LEVEL_DEBUG);

													break;
												case 'file_exists':
												case 'is_dir':
													$path = __sizeof($options) === 1 ? rrdp_resolve_rra_path($options[0]) : false;

													$rrdp_exec_status = $path !== false && $cmd($path);

													rrdp_system__socket_write($socket_client, encrypt(($rrdp_exec_status === true) ? RRD_OK : RRD_ERROR , $client_public_key) . $end_of_sequence);
													__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . (($rrdp_exec_status === true) ? RRD_OK : RRD_ERROR), 'IPC', SEVERITY_LEVEL_DEBUG);

													break;
												case 'mkdir':
													$path = __sizeof($options) === 1 ? rrdp_resolve_rra_path($options[0], false) : false;

													$rrdp_exec_status = $path !== false && mkdir($path, 0700, true);

													rrdp_system__socket_write($socket_client, encrypt(($rrdp_exec_status === true) ? RRD_OK : RRD_ERROR , $client_public_key) . $end_of_sequence);
													__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . (($rrdp_exec_status === true) ? RRD_OK : RRD_ERROR), 'IPC', SEVERITY_LEVEL_DEBUG);

													break;
												case 'archive':
													$source_file  = __sizeof($options) === 1 ? rrdp_resolve_rra_path($options[0]) : false;
													$archive_base = $rrdp_config['path_rra_archive'] ? realpath($rrdp_config['path_rra_archive']) : false;

													if ($source_file !== false && str_ends_with(strtolower($source_file), '.rrd') && $archive_base !== false) {
														$relative    = ltrim(substr($source_file, strlen(realpath($rrdp_config['path_rra']))), DIRECTORY_SEPARATOR);
														$target_file = rrdp_resolve_path_within($archive_base, $relative, false);

														if ($target_file !== false) {
															$target_dir = dirname($target_file);

															if (!is_dir($target_dir)) {
																mkdir($target_dir, 0700, true);
															}

															$rrdp_exec_status = rename($source_file, $target_file);
														}
													} else {
														$rrdp_exec_status = false;
													}

													rrdp_system__socket_write($socket_client, encrypt((($rrdp_exec_status === true) ? RRD_OK : RRD_ERROR), $client_public_key) . $end_of_sequence);
													__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . (($rrdp_exec_status === true) ? RRD_OK : RRD_ERROR), 'IPC', SEVERITY_LEVEL_DEBUG);

													break;
												case 'unlink':
													$path = __sizeof($options) === 1 ? rrdp_resolve_rra_path($options[0]) : false;

													$rrdp_exec_status = $path !== false && str_ends_with(strtolower($path), '.rrd') && unlink($path);

													rrdp_system__socket_write($socket_client, encrypt((($rrdp_exec_status === true) ? RRD_OK : RRD_ERROR), $client_public_key) . $end_of_sequence);
													__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . (($rrdp_exec_status === true) ? RRD_OK : RRD_ERROR), 'IPC', SEVERITY_LEVEL_DEBUG);

													break;
												case 'removespikes':
													$parsed_options   = rrdp_parse_removespikes_options($cmd_options);

													// inherit the full process environment (getenv() unlike $_ENV isn't gated by variables_order)
													$environment      = array_merge(getenv(), ['RRDP_RRDTOOL_PATH' => $rrdp_config['path_rrdtool']]);
													$result           = $parsed_options === false ? false : rrdp_run_process(array_merge([PHP_BINARY, '-q', $rrdp_config['path_cli'] . '/removespikes.php'], $parsed_options), $environment);
													$rrdp_exec_status = $result !== false && $result['status'] === 0;
													$rrdp_exec_return = $result !== false ? $result['stdout'] . $result['stderr'] : 'Invalid removespikes options';

													$response = $rrdp_exec_return . "\r\n" . ($rrdp_exec_status ? RRD_OK : RRD_ERROR);
													rrdp_system__socket_write($socket_client, encrypt($response, $client_public_key) . $end_of_sequence);
													__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . $response, 'IPC', SEVERITY_LEVEL_DEBUG);

													break;
												case 'version':
													rrdp_system__socket_write($socket_client, encrypt(RRDP_VERSION_FULL . "\r\n" . RRD_OK, $client_public_key) . $end_of_sequence);
													__logging(LOGGING_LOCATION_BUFFERED, 'RESPONSE: ' . RRDP_VERSION_FULL . "\r\n" . RRD_OK, 'IPC', SEVERITY_LEVEL_DEBUG);

													break;
												default:
													break;
											}

											// update local cache for MSR
											if ($rrdp_exec_status === true) {
												if (in_array($cmd , $rrdtool_msr_cmds, true) === true) {
													[$mtime,$time] = explode(' ',microtime());

													$mtime  = (float) $mtime;
													$time   = (int) $time;
													$offset = $time % 10;
													$block  = $time - $offset + 10;

													$rrdp_status['msr_commands'][$block][$offset + $mtime . '_' . $socket_resource_id] = $cmd . ' ' . $cmd_options;

													if (__sizeof($rrdp_status['msr_commands']) > 1 || $time >= $block) {
														$msr_block = key($rrdp_status['msr_commands']);

														$msr_message['type'] = 'msr';

														$msr_message['msr_commands'][$msr_block] = $rrdp_status['msr_commands'][$msr_block];

														if (@socket_write($ipc_socket_parent, serialize($msr_message) . "\r\n")) {
															unset($rrdp_status['msr_commands'][$msr_block]);
															unset($msr_message);
															$rrdp_status = $rrdp_status_backup;
															usleep(10000);
														}
													}
												}
											}
										} else {
											// kick that client if it does not know how to talk to me
											__logging(LOGGING_LOCATION_BUFFERED, 'Client is using invalid commands.', 'IPC', SEVERITY_LEVEL_ERROR);
											rrdp_system__socket_write($socket_client, encrypt(RRD_ERROR . ' % Invalid input detected', $client_public_key) . $end_of_sequence);

											$rrdp_status['status'] = 'CLOSEDOWN_BY_VIOLATION';

											break 4;
										}
									}
								}

								if (strlen($input) > $max_input_size) {
									rrdp_system__socket_write($socket_client, (($client_authenticated) ? encrypt(RRD_ERROR . ' Request too large', $client_public_key) : RRD_ERROR . ' Request too large') . $end_of_sequence);
									__logging(LOGGING_LOCATION_BUFFERED, 'Client request exceeded the maximum frame size', 'IPC', SEVERITY_LEVEL_WARNING);
									$rrdp_status['status'] = 'CLOSEDOWN_BY_VIOLATION';

									break 3;
								}
							}
						}
					}
				} elseif ($socket_resource_id == $ipc_parent_resource_id) {
					// RRDtool proxy is talking to us

					while (1) {
						$recv = @socket_read($ipc_socket_parent, 8192, PHP_BINARY_READ);

						if ($recv === false) {
							// timeout
							break;
						}

						if ($recv == '') {
							// socket session dropped by proxy
							break;
						} else {
							$input .= $recv;

							if (substr($input, -1) == "\n") {
								rrdp_system__count('bytes_received', rrdp_system__calc_bytes($input));

								$status = unserialize(trim($input));

								if ($status !== false && $status['type']) {
									switch($status['type']) {
										case 'shutdown':
											rrdp_system__socket_write($socket_client, (($client_authenticated) ? encrypt(RRD_ERROR . 'Shutting down ...', $client_public_key) : RRD_ERROR . 'Shutting down ...') . $end_of_sequence);
											socket_close($ipc_socket_parent);
											exit;
										case 'status':
											socket_write($ipc_socket_parent, "running\r\n");

											break 4;
										default:
											break 3;
									}
								}
							} else {
								continue;
							}
						}
					}
				}
			}
		} else {
			rrdp_system__socket_write($socket_client, 'Timeout' . $end_of_sequence);
			$rrdp_status['status'] = 'CLOSEDOWN_BY_TIMEOUT';

			break;
		}
	}

	if ($rrdtool_process) {
		rrdtool_pipe_close($rrdtool_process);
	}
}