Autodetect Telnet IAC modes, and if in binary mode esc 0xff chars

app/Classes/Sock/SocketClient.php

@@ -197,6 +197,7 @@ final class SocketClient {
 		return match ($key) {
 			'address_remote', 'port_remote' => $this->{$key},
 			'cps', 'speed' => Arr::get($this->session,$key),
+			'iac_bin' => Arr::get($this->session,$key),
 			'rx_free' => self::RX_BUF_SIZE-$this->rx_left,
 			'rx_left' => strlen($this->rx_buf),
 			'tx_free' => self::TX_BUF_SIZE-strlen($this->tx_buf),
@@ -210,6 +211,7 @@ final class SocketClient {
 		switch ($key) {
 			case 'cps':
 			case 'speed':
+			case 'iac_bin':
 				$this->session[$key] = $value;
 				break;
 
@@ -428,11 +430,45 @@ final class SocketClient {
 				Log::debug(sprintf('%s:- Returning [%d] chars from the RX buffer',self::LOGKEY,$len));
 
 			$result = substr($this->rx_buf,0,$len);
-			$this->rx_buf = substr($this->rx_buf,strlen($result));
+			if ($flags !== MSG_PEEK)
+				$this->rx_buf = substr($this->rx_buf,strlen($result));
 
-			return $result;
+			// In case we are in Telnet Binary Mode
+			if ($this->iac_bin) {
+				if (self::DEBUG)
+					Log::debug(sprintf('%s:- Telnet IAC Binary Mode, looking for ff ff',self::LOGKEY),['result'=>hex_dump($result)]);
+
+				// if the last char is ff, we need to get the next char
+				if (str_ends_with($result,"\xff")) {
+					if (self::DEBUG)
+						Log::debug(sprintf('%s:  - We have a hit',self::LOGKEY));
+
+					// If we have it in our buffer, just get it
+					if ($this->rx_left) {
+						$result .= substr($this->rx_buf,0,1);
+						$this->rx_buf = substr($this->rx_buf,1);
+
+					// Else put everything back into rx_buf, and increase len by 1
+					} else {
+						$this->rx_buf = $result;
+						$len++;
+						$result = '';
+					}
+				}
+
+				if (strlen($result) > 1)
+					$result = str_replace("\xff\xff","\xff",$result);
+
+				if (strlen($result))
+					return $result;
+
+			} else
+				return $result;
 		}
 
+		if (self::DEBUG)
+			Log::debug(sprintf('%s:- Buffer doesnt have [%d] chars, it only has [%d], or it ends with 0xff',self::LOGKEY,$len,strlen($this->rx_buf)),['rx_buf'=>hex_dump($this->rx_buf)]);
+
 		if ($timeout && (! $this->hasData($timeout)))
 			throw new SocketException(SocketException::SOCKET_TIMEOUT,$timeout);
 
@@ -486,13 +522,19 @@ final class SocketClient {
 			}
 		}
 
+		if ($flags === MSG_PEEK) {
+			Log::debug(sprintf('%s:- Returning [%d] chars as a result of a PEEK operation, buffer would have [%d], but still has [%d]',self::LOGKEY,$len,strlen($this->rx_buf.$buf),strlen($this->rx_buf)),['rx_buf'=>hex_dump($this->rx_buf),'buf'=>hex_dump($buf)]);
+
+			return substr($this->rx_buf.$buf,0,$len);
+		}
+
 		$this->rx_buf .= $buf;
 
 		if (self::DEBUG)
 			Log::debug(sprintf('%s:- Added [%d] chars to the RX buffer',self::LOGKEY,strlen($buf)),['rx_buf'=>hex_dump($this->rx_buf)]);
 
 		// Loop again and return the data, now that it is in the RX buffer
-		return $this->read($timeout,$len);
+		return $this->read($timeout,$len,$flags);
 	}
 
 	/**
@@ -511,6 +553,9 @@ final class SocketClient {
 		else
 			throw new SocketException(SocketException::SOCKET_TIMEOUT,$timeout);
 
+		if (self::DEBUG)
+			Log::debug(sprintf('%s:+ read_ch [%c] (%x)',self::LOGKEY,$ch,ord($ch)));
+
 		return ord($ch);
 	}
 
@@ -549,6 +594,11 @@ final class SocketClient {
 		if (self::DEBUG)
 			Log::debug(sprintf('%s:- Sending [%d] chars [%s]',self::LOGKEY,strlen($message),Str::limit($message,15)));
 
+		if ($this->iac_bin) {
+			Log::debug(sprintf('%s:- IAC_BIN mode, looking for 0xff',self::LOGKEY));
+			$message = str_replace("\xff","\xff\xff",$message);
+		}
+
 		switch ($this->type) {
 			case SOCK_STREAM:
 				return socket_write($this->connection,$message,strlen($message));