我实际上是在尝试使用 Qt4 制作 DNS 代理应用程序。如果我将 DNS 名称服务器设置为“localhost”,那么我想将所有 DNS 请求转发到 remoteSocket 对象中指定的服务器。除了将数据从 remoteSocket 对象发送回请求 DNS 查找的 localSocket 对象外,一切似乎都工作正常。
在写入 localSocket 时,我需要了解什么具体信息吗?问题似乎出在 readResponse() 中。
#include "dns.h"
Dns::Dns()
{
}
void Dns::initSocket()
{
localDatagram = new QByteArray();
remoteDatagram = new QByteArray();
localSocket = new QUdpSocket();
connect(localSocket, SIGNAL(readyRead()), this, SLOT(readRequest()), Qt::DirectConnection);
localSocket->bind(QHostAddress::LocalHost, 53);
remoteSocket = new QUdpSocket();
remoteSocket->connectToHost(QHostAddress("4.2.2.1"), 53);
connect(remoteSocket, SIGNAL(readyRead()), this, SLOT(readResponse()), Qt::DirectConnection);
}
void Dns::readRequest()
{
while (localSocket->hasPendingDatagrams()) {
localDatagram->resize(localSocket->pendingDatagramSize());\
localSocket->readDatagram(localDatagram->data(), localDatagram->size());
remoteSocket->write(*localDatagram);
}
}
void Dns::readResponse()
{
QByteArray bytes(remoteSocket->readAll());
qDebug() << "BYTES: [" << bytes.toBase64() << "]";
localSocket->write(bytes);
}
最佳答案
我假设使用 QUdpSocket::bind(),生成的套接字对象将能够使用访问方法获得 peerAddress/peerPort,但事实并非如此。
最终的解决方案是:
QHostAddress sender;
quint16 senderPort;
localSocket->readDatagram(localDatagram->data(), localDatagram->size(), &sender, &senderPort);
并且在 readResponse() 中,
localSocket->writeDatagram(bytes, sender, senderPort);
关于c++ - Qt4 DNS 代理 QUdpSocket,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/1392494/