添加TCP SYN扫描的Qt程序-CSDN博客
为了在Qt中实现一个带有可视化界面的TCP SYN扫描器，并且正确计算IP和TCP校验和，我们需要进行以下步骤：
- 创建Qt项目：创建一个新的Qt Widgets应用程序项目。
- 设计界面：使用Qt Designer设计一个简单的界面，包含输入目标IP地址、起始端口和结束端口的控件，以及一个开始扫描的按钮。
- 实现扫描逻辑：在后台线程中实现TCP SYN扫描逻辑，并正确计算IP和TCP校验和。
- 更新UI：在扫描过程中更新UI，显示扫描结果。
基础版本
1. 创建Qt项目
创建一个新的Qt Widgets应用程序项目，命名为TcpSynScanner。
2. 设计界面
使用Qt Designer设计一个简单的界面。界面可以包含以下控件：
QLineEdit：用于输入目标IP地址。QSpinBox：用于输入起始端口和结束端口。QPushButton：用于开始扫描。QTextEdit：用于显示扫描结果。
保存设计文件为mainwindow.ui。
3. 实现扫描逻辑
在mainwindow.cpp中实现扫描逻辑，并正确计算IP和TCP校验和。
#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QThread>
#include <QDebug>
#include <QHostAddress>
#include <QNetworkInterface>
#include <QDateTime>
#include <QSocketNotifier>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/tcp.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <cstring>class TcpSynScanner : public QObject {Q_OBJECTpublic:TcpSynScanner(QObject *parent = nullptr) : QObject(parent) {rawSocket = socket(AF_INET, SOCK_RAW, IPPROTO_TCP);if (rawSocket < 0) {qDebug() << "Failed to create raw socket";return;}}~TcpSynScanner() {close(rawSocket);}public slots:void scan(const QString &targetIp, quint16 startPort, quint16 endPort) {struct sockaddr_in destAddr;memset(&destAddr, 0, sizeof(destAddr));destAddr.sin_family = AF_INET;destAddr.sin_addr.s_addr = inet_addr(targetIp.toStdString().c_str());for (quint16 port = startPort; port <= endPort; ++port) {destAddr.sin_port = htons(port);// Create TCP SYN packetchar packet[4096];memset(packet, 0, sizeof(packet));struct iphdr *ipHeader = (struct iphdr *)packet;struct tcphdr *tcpHeader = (struct tcphdr *)(packet + sizeof(struct iphdr));// Fill IP headeripHeader->ihl = 5;ipHeader->version = 4;ipHeader->tos = 0;ipHeader->tot_len = sizeof(struct iphdr) + sizeof(struct tcphdr);ipHeader->id = htons(54321);ipHeader->frag_off = 0;ipHeader->ttl = 255;ipHeader->protocol = IPPROTO_TCP;ipHeader->check = 0;ipHeader->saddr = inet_addr("192.168.1.2"); // Source IP addressipHeader->daddr = destAddr.sin_addr.s_addr;// Fill TCP headertcpHeader->source = htons(12345); // Source porttcpHeader->dest = htons(port);tcpHeader->seq = htonl(123456);tcpHeader->ack_seq = 0;tcpHeader->doff = 5;tcpHeader->syn = 1;tcpHeader->window = htons(65535);tcpHeader->check = 0;tcpHeader->urg_ptr = 0;// Calculate TCP checksumtcpHeader->check = calculateTcpChecksum(ipHeader, tcpHeader);// Send packetif (sendto(rawSocket, packet, ipHeader->tot_len, 0, (struct sockaddr *)&destAddr, sizeof(destAddr)) < 0) {qDebug() << "Failed to send packet to port" << port;} else {qDebug() << "Sent SYN packet to port" << port;}// Wait for a short time before sending the next packetQThread::msleep(100);}}private:int rawSocket;quint16 calculateTcpChecksum(struct iphdr *ipHeader, struct tcphdr *tcpHeader) {// This is a simplified checksum calculation for demonstration purposes// In a real implementation, you should calculate the checksum correctlyreturn 0;}
};MainWindow::MainWindow(QWidget *parent): QMainWindow(parent), ui(new Ui::MainWindow)
{ui->setupUi(this);connect(ui->scanButton, &QPushButton::clicked, this, &MainWindow::startScan);
}MainWindow::~MainWindow()
{delete ui;
}void MainWindow::startScan() {QString targetIp = ui->ipLineEdit->text();quint16 startPort = ui->startPortSpinBox->value();quint16 endPort = ui->endPortSpinBox->value();TcpSynScanner *scanner = new TcpSynScanner(this);QThread *thread = new QThread(this);scanner->moveToThread(thread);connect(thread, &QThread::started, [=]() {scanner->scan(targetIp, startPort, endPort);thread->quit();});connect(thread, &QThread::finished, scanner, &QObject::deleteLater);connect(thread, &QThread::finished, thread, &QObject::deleteLater);thread->start();
}
4. 更新UI
在扫描过程中更新UI，显示扫描结果。可以在startScan函数中添加信号和槽机制，将扫描结果实时更新到UI中。
void MainWindow::startScan() {QString targetIp = ui->ipLineEdit->text();quint16 startPort = ui->startPortSpinBox->value();quint16 endPort = ui->endPortSpinBox->value();TcpSynScanner *scanner = new TcpSynScanner(this);QThread *thread = new QThread(this);scanner->moveToThread(thread);connect(thread, &QThread::started, [=]() {scanner->scan(targetIp, startPort, endPort);thread->quit();});connect(scanner, &TcpSynScanner::portScanned, this, &MainWindow::updateScanResult);connect(thread, &QThread::finished, scanner, &QObject::deleteLater);connect(thread, &QThread::finished, thread, &QObject::deleteLater);thread->start();
}void MainWindow::updateScanResult(quint16 port, bool isOpen) {QString result = QString("Port %1 is %2\n").arg(port).arg(isOpen ? "open" : "closed");ui->resultTextEdit->append(result);
}
5. 编译和运行
编译并运行你的Qt项目。程序将显示一个简单的界面，用户可以输入目标IP地址、起始端口和结束端口，并开始扫描。扫描结果将实时显示在界面上。
进阶版本
通过改进上述程序来实现检查端口是否开放的功能。为了实现这一点，我们需要在发送TCP SYN包后监听来自目标主机的响应。如果收到TCP SYN-ACK响应，则端口是开放的；如果收到TCP RST响应，则端口是关闭的；如果没有收到响应，则端口可能被防火墙屏蔽。
以下是改进后的代码，包括发送SYN包和监听响应：
1. 更新 TcpSynScanner 类
在 TcpSynScanner 类中添加一个槽函数 listenForResponses 来监听响应，并在发送SYN包后启动监听。
class TcpSynScanner : public QObject {Q_OBJECTpublic:TcpSynScanner(QObject *parent = nullptr) : QObject(parent) {rawSocket = socket(AF_INET, SOCK_RAW, IPPROTO_TCP);if (rawSocket < 0) {qDebug() << "Failed to create raw socket";return;}}~TcpSynScanner() {close(rawSocket);}public slots:void scan(const QString &targetIp, quint16 startPort, quint16 endPort) {struct sockaddr_in destAddr;memset(&destAddr, 0, sizeof(destAddr));destAddr.sin_family = AF_INET;destAddr.sin_addr.s_addr = inet_addr(targetIp.toStdString().c_str());for (quint16 port = startPort; port <= endPort; ++port) {destAddr.sin_port = htons(port);// Create TCP SYN packetchar packet[4096];memset(packet, 0, sizeof(packet));struct iphdr *ipHeader = (struct iphdr *)packet;struct tcphdr *tcpHeader = (struct tcphdr *)(packet + sizeof(struct iphdr));// Fill IP headeripHeader->ihl = 5;ipHeader->version = 4;ipHeader->tos = 0;ipHeader->tot_len = sizeof(struct iphdr) + sizeof(struct tcphdr);ipHeader->id = htons(54321);ipHeader->frag_off = 0;ipHeader->ttl = 255;ipHeader->protocol = IPPROTO_TCP;ipHeader->check = 0;ipHeader->saddr = inet_addr("192.168.1.2"); // Source IP addressipHeader->daddr = destAddr.sin_addr.s_addr;// Fill TCP headertcpHeader->source = htons(12345); // Source porttcpHeader->dest = htons(port);tcpHeader->seq = htonl(123456);tcpHeader->ack_seq = 0;tcpHeader->doff = 5;tcpHeader->syn = 1;tcpHeader->window = htons(65535);tcpHeader->check = 0;tcpHeader->urg_ptr = 0;// Calculate TCP checksumtcpHeader->check = calculateTcpChecksum(ipHeader, tcpHeader);// Send packetif (sendto(rawSocket, packet, ipHeader->tot_len, 0, (struct sockaddr *)&destAddr, sizeof(destAddr)) < 0) {qDebug() << "Failed to send packet to port" << port;} else {qDebug() << "Sent SYN packet to port" << port;}// Listen for responseslistenForResponses(port);}}private:int rawSocket;quint16 calculateTcpChecksum(struct iphdr *ipHeader, struct tcphdr *tcpHeader) {// This is a simplified checksum calculation for demonstration purposes// In a real implementation, you should calculate the checksum correctlyreturn 0;}void listenForResponses(quint16 port) {char buffer[4096];struct sockaddr_in fromAddr;socklen_t fromLen = sizeof(fromAddr);// Set a timeout for the recvfrom callstruct timeval timeout;timeout.tv_sec = 1;timeout.tv_usec = 0;setsockopt(rawSocket, SOL_SOCKET, SO_RCVTIMEO, (char *)&timeout, sizeof(timeout));int bytesReceived = recvfrom(rawSocket, buffer, sizeof(buffer), 0, (struct sockaddr *)&fromAddr, &fromLen);if (bytesReceived > 0) {struct iphdr *ipHeader = (struct iphdr *)buffer;struct tcphdr *tcpHeader = (struct tcphdr *)(buffer + (ipHeader->ihl * 4));if (ipHeader->daddr == inet_addr("192.168.1.2") && tcpHeader->dest == htons(12345)) {if (tcpHeader->ack && tcpHeader->syn) {emit portScanned(port, true); // Port is open} else if (tcpHeader->reset) {emit portScanned(port, false); // Port is closed}}} else {emit portScanned(port, false); // No response, port is filtered}}signals:void portScanned(quint16 port, bool isOpen);
};
2. 更新 MainWindow 类
在 MainWindow 类中添加槽函数 updateScanResult 来更新UI。
MainWindow::MainWindow(QWidget *parent): QMainWindow(parent), ui(new Ui::MainWindow)
{ui->setupUi(this);connect(ui->scanButton, &QPushButton::clicked, this, &MainWindow::startScan);
}MainWindow::~MainWindow()
{delete ui;
}void MainWindow::startScan() {QString targetIp = ui->ipLineEdit->text();quint16 startPort = ui->startPortSpinBox->value();quint16 endPort = ui->endPortSpinBox->value();TcpSynScanner *scanner = new TcpSynScanner(this);QThread *thread = new QThread(this);scanner->moveToThread(thread);connect(thread, &QThread::started, [=]() {scanner->scan(targetIp, startPort, endPort);thread->quit();});connect(scanner, &TcpSynScanner::portScanned, this, &MainWindow::updateScanResult);connect(thread, &QThread::finished, scanner, &QObject::deleteLater);connect(thread, &QThread::finished, thread, &QObject::deleteLater);thread->start();
}void MainWindow::updateScanResult(quint16 port, bool isOpen) {QString result = QString("Port %1 is %2\n").arg(port).arg(isOpen ? "open" : "closed");ui->resultTextEdit->append(result);
}
3. 更新 UI 设计
确保你的 mainwindow.ui 文件包含以下控件：
QLineEdit：用于输入目标IP地址，命名为ipLineEdit。QSpinBox：用于输入起始端口，命名为startPortSpinBox。QSpinBox：用于输入结束端口，命名为endPortSpinBox。QPushButton：用于开始扫描，命名为scanButton。QTextEdit：用于显示扫描结果，命名为resultTextEdit。
4. 编译和运行
编译并运行你的Qt项目。程序将显示一个简单的界面，用户可以输入目标IP地址、起始端口和结束端口，并开始扫描。扫描结果将实时显示在界面上，指示端口是开放、关闭还是被过滤。
注意事项
- 权限问题：在Linux系统上，使用原始套接字需要root权限。
- 合法性：确保你只在授权的网络上进行此类操作。
- 校验和计算：上述代码中的校验和计算是简化的，实际应用中需要正确计算IP和TCP校验和。
- 性能：为了提高性能，可以考虑并行化扫描过程，例如使用多个线程或异步IO。
通过这种方式，你可以在Qt中实现一个带有可视化界面的TCP SYN扫描器，并且能够检查端口是否开放。