请教高手qt+kdevelop实现防火墙开发技术

wayd2001

小弟最近在研究netfilter框架和qt+develop界面开发，目前已经使用qt制作出来了界面，并将ui文件导入到kdevelop中，运行的时候

界面可以正常的显示，剩下的工作是功能代码的实现，首先防火墙内核代码函数的调用问题，小弟一直束手无策，不指点如何下手

具体来说，比如一段内核代码：

#define __KERNEL__
#define MODULE

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/netfilter.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <linux/netdevice.h>
#include <linux/if_ether.h>
#include <linux/if_packet.h>
#include <net/tcp.h>
#include <linux/netfilter_ipv4.h>


static struct nf_hook_ops nfho;


unsigned int hook_func(unsigned int hooknum,
                       struct sk_buff **skb,
                       const struct net_device *in,
                       const struct net_device *out,
                       int (*okfn)(struct sk_buff *))
{
    struct sk_buff *sb = *skb;
    unsigned char src_ip[4];
    *(unsigned int *)src_ip = sb->nh.iph->saddr;
    printk("A packet from:%d.%d.%d.%d Detected!",
                 src_ip[0],src_ip[1],src_ip[2],src_ip[3]);
    switch(sb->nh.iph->protocol)
    {
       case IPPROTO_TCP:
           printk("It's a TCP PACKET\n");break;
       case IPPROTO_ICMP:
          printk("It's a ICMP PACKET\n");break;
      case IPPROTO_UDP:
         printk("It's a UDP PACKET\n");break;
    }
    return NF_ACCEPT;         
}


int init_module()
{
  
    nfho.hook = hook_func;         
    nfho.hooknum  = NF_IP_PRE_ROUTING;
    nfho.pf       = PF_INET;
    nfho.priority = NF_IP_PRI_FIRST;  

    nf_register_hook(&nfho);

    return 0;
}

void cleanup_module()
{
    nf_unregister_hook(&nfho);
}

这实际上是对前面几篇文章的几个小程序的组合，实际上就是对sk_buff 结构体的的两个元素进行了检测，就得到了源地址和协议的信息。上面的这条语句对于那些C不是很熟悉的人可能吃力了一点：

*(unsigned int *)src_ip = sb->nh.iph->saddr;

我稍微的解释一下，网络的源地址是4个子节的int，因此我定义了一个4个子节的数组src_ip，从而每一个子节里面就存储的点分十进制的一个数，为了一次完成赋值，我把src_ip 转成unsigned int指针，就可以一次4个字节一起访问了。

下面是这个程序的测试结果：

A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.8 Detected!It's a UDP PACKET
A packet from:210.43.106.214 Detected!It's a UDP PACKET
A packet from:210.43.106.246 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.106.112 Detected!It's a UDP PACKET
A packet from:210.43.107.8 Detected!It's a UDP PACKET
A packet from:210.43.106.214 Detected!It's a UDP PACKET
A packet from:210.43.106.246 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.106.112 Detected!It's a UDP PACKET
A packet from:210.43.106.214 Detected!It's a UDP PACKET
A packet from:210.43.106.246 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.106.112 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.106.254 Detected!It's a UDP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.107.230 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.106.214 Detected!It's a UDP PACKET
A packet from:210.43.107.230 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.106.214 Detected!It's a UDP PACKET
A packet from:210.43.107.230 Detected!It's a UDP PACKET
A packet from:210.43.106.96 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.106.112 Detected!It's a UDP PACKET
A packet from:210.43.106.214 Detected!It's a UDP PACKET
A packet from:210.43.107.230 Detected!It's a UDP PACKET
A packet from:210.43.106.96 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.106.112 Detected!It's a UDP PACKET
A packet from:210.43.107.230 Detected!It's a UDP PACKET
A packet from:210.43.106.96 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.106.112 Detected!It's a UDP PACKET
A packet from:210.43.107.230 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.106.214 Detected!It's a UDP PACKET
A packet from:210.43.106.96 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:192.168.1.1 Detected!It's a UDP PACKET
A packet from:192.168.1.1 Detected!It's a UDP PACKET
A packet from:192.168.1.1 Detected!It's a UDP PACKET
A packet from:192.168.1.1 Detected!It's a UDP PACKET
A packet from:192.168.1.1 Detected!It's a UDP PACKET
A packet from:192.168.1.1 Detected!It's a UDP PACKET
A packet from:192.168.1.1 Detected!It's a UDP PACKET
A packet from:192.168.1.1 Detected!It's a UDP PACKET
A packet from:192.168.1.1 Detected!It's a UDP PACKET
A packet from:192.168.1.1 Detected!It's a UDP PACKET
A packet from:210.43.106.214 Detected!It's a UDP PACKET
A packet from:210.43.106.96 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.107.130 Detected!It's a ICMP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.106.214 Detected!It's a UDP PACKET
A packet from:210.43.106.96 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.107.130 Detected!It's a ICMP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.106.112 Detected!It's a UDP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.107.130 Detected!It's a ICMP PACKET
A packet from:210.43.106.96 Detected!It's a UDP PACKET
A packet from:210.43.106.210 Detected!It's a UDP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.106.112 Detected!It's a UDP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET
A packet from:210.43.107.136 Detected!It's a UDP PACKET
A packet from:210.43.107.130 Detected!It's a TCP PACKET

如果需要对包的端口进行分析的话，就要对IP报文的数据段(sb->data)进行分析了（TCP和UDP等包都是作为IP的数据而存在的），大家可以参考一下相应的资料。

红色部分为引用达人的代码段，我想吧这个功能加入到我的防火墙界面程序中，比如点击一个按钮，就可以实现上述功能，应该怎么具体

操作那，比如一些头文件的加载，请各位高手指点

谢谢啦

scutan

直接用system这些系统调用就可以了啊.

Godbach

LZ是一个问题多论坛发啊。要是GUI开发的话，还是直接封装你的命令吧。如2楼的，用system。当然，有些是可以直接调用函数的。
system("insmod yourmod.ko");

hongchunhua

netfilter可以将数据包发送到用户空间，然后在用户空间对数据包处理后又回到原来的调用，所以按照lz的设计，是否可以考虑这种方法？

Godbach

原帖由 hongchunhua 于 2008-12-12 16:21 发表
netfilter可以将数据包发送到用户空间，然后在用户空间对数据包处理后又回到原来的调用，所以按照lz的设计，是否可以考虑这种方法？

那就是使用IP Queue了