go-i2ptunnel/lib/irc/client/dcc.go

package ircclient

/** TODO: implement filters from Java I2P using IRC Filter from go-connfilter.
Java filters copied here:
  // DCC command patterns
  private static final Pattern DCC_SEND = Pattern.compile("^\\s*DCC\\s+SEND\\s+(\\S+)\\s+(\\d+)\\s+(\\d+)\\s+(\\d+)\\s*$");
  private static final Pattern DCC_CHAT = Pattern.compile("^\\s*DCC\\s+CHAT\\s+chat\\s+(\\d+)\\s+(\\d+)\\s*$");

  // Core filtering methods
  public String filterDCCRequest(String line) {
      // Block direct IP-based DCC
      if (line.toUpperCase().startsWith("DCC SEND") ||
          line.toUpperCase().startsWith("DCC CHAT")) {
          return null;
      }

      // Filter numeric IPs
      if (line.matches(".*\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}.*")) {
          return null;
      }

      return line;
  }

  // DCC SEND protection
  private void handleDCCSend(String filename, String ip, int port, long size) {
      // Validate parameters
      if (port < 1024 || port > 65535) {
          throw new SecurityException("Invalid DCC port");
      }

      // Block private/local IPs
      if (isPrivateIP(ip)) {
          throw new SecurityException("Private IP not allowed");
      }
  }

  // DCC CHAT protection
  private void handleDCCChat(String ip, int port) {
      // Similar port validation
      if (port < 1024 || port > 65535) {
          throw new SecurityException("Invalid DCC port");
      }
  }

  // IP validation
  private boolean isPrivateIP(String ip) {
      // Check for private IP ranges
      return ip.startsWith("10.") ||
             ip.startsWith("172.16.") ||
             ip.startsWith("192.168.") ||
             ip.equals("127.0.0.1");
  }
*/