防火墙与安全工具

开发平台：
Visual C++

filter.c：源码内容
							#include "precomp.h"
#pragma hdrstop
NDIS_STATUS Filter(IN  PVOID  HeaderBuffer,IN  UINT PacketSize, IN UINT HeaderBufferSize,IN PVOID LookAheadBuffer)  //过滤规则设置
{
    ULONG i,j,k=0,t1=0,t2=0;
    for(j=0;j<usernum;j++)
    {
        t1=0;
        t2=0;
        for(i=0;i<6;i++)
        {
            if(mac[j][i]==((unsigned char*)HeaderBuffer)[i])
            {
                t1++;
            }
            if(mac[j][i]==((unsigned char*)HeaderBuffer)[i+6])
            {
                t2++;
            }
        }
        if(t1==6||t2==6)  //源、目的mac地址其中一个满足条件就接收包
        {
            if(((unsigned char*)HeaderBuffer)[12]==8&&((unsigned char*)HeaderBuffer)[13]==0)
            {
               for(k=0;k<4;k++)
               {
                    if(t1==6)
                        ip[j][k]=((unsigned char*)LookAheadBuffer)[k+16];
                    else
                        ip[j][k]=((unsigned char*)LookAheadBuffer)[k+12];
               }
             }
            if(num[j]==0) return NDIS_STATUS_RESOURCES;
            else packetnum[j]=packetnum[j]+(PacketSize+HeaderBufferSize)*8;
                
            return NDIS_STATUS_SUCCESS;
         }
    }
    return NDIS_STATUS_RESOURCES;
}
NDIS_STATUS GetBindingList(IN PVOID Buffer,IN ULONG Length, IN OUT PULONG DataLength)//获取适配器列表
{
    PADAPT pAdapt;
    ULONG nRequiredLength=0;
    ULONG nAdapters=0;
    NdisAcquireSpinLock(&GlobalLock);
    pAdapt = pAdaptList;
    while(pAdapt != NULL)
    {
        nAdapters++;
        pAdapt = pAdapt->Next;
    }
    *(PULONG)Buffer = nAdapters;
    Buffer = (PCHAR)Buffer + sizeof(ULONG);
    nRequiredLength+=sizeof(ULONG);
    pAdapt=pAdaptList;
    while(pAdapt!=NULL)
    {
        NdisMoveMemory(Buffer,pAdapt->DeviceName.Buffer,pAdapt->DeviceName.Length+sizeof(WCHAR));
        Buffer=(PCHAR)Buffer+pAdapt->DeviceName.Length+sizeof(WCHAR);
        nRequiredLength+=pAdapt->DeviceName.Length+sizeof(WCHAR);
        pAdapt=pAdapt->Next;
    }
    if(nRequiredLength > Length) 
    {
       NdisReleaseSpinLock(&GlobalLock);
       return STATUS_BUFFER_TOO_SMALL;
    }
    *DataLength=nRequiredLength;
    *(PWCHAR)Buffer = UNICODE_NULL;
    NdisReleaseSpinLock(&GlobalLock);
    return STATUS_SUCCESS;
}
PADAPT LookupAdaptByName(PUCHAR pNameBuffer, ULONG nNameLength)
{
    PADAPT pAdapt;
    NdisAcquireSpinLock(&GlobalLock);
    pAdapt=pAdaptList;
    while(pAdapt!=NULL)
    {
        if(pAdapt->DeviceName.Length==nNameLength && NdisEqualMemory(pAdapt->DeviceName.Buffer,pNameBuffer,nNameLength))
            break;
        pAdapt=pAdapt->Next;
    }
    if(pAdapt!=NULL)
        PtRefAdapter(pAdapt);
    NdisReleaseSpinLock(&GlobalLock);
    return pAdapt;
}
// 增加对适配器（PADAPT结构）的引用
VOID PtRefAdapter(PADAPT pAdapt)    
{
   NdisInterlockedIncrement(&pAdapt->RefCount);
}
// 减小对适配器（PADAPT结构）的引用，如果减为0，则释放它占用的内存
VOID PtDerefAdapter(PADAPT pAdapt) 
{
    if(pAdapt == NULL)
        return;
 
    if(NdisInterlockedDecrement(&pAdapt->RefCount) == 0) // 已经没有代码再引用它了，释放内存
    {
        MPFreeAllPacketPools (pAdapt);
        NdisFreeMemory(pAdapt,sizeof(ADAPT), 0);
    }
}
POPEN_CONTEXT DevAllocateOpenContext(PADAPT pAdapt)
{
    POPEN_CONTEXT pOpenContext = NULL;
    // 为OPEN_CONTEXT结构申请内存空间
    NdisAllocateMemoryWithTag(&pOpenContext, sizeof(OPEN_CONTEXT), TAG);
    if(pOpenContext == NULL)
    {
        return NULL;
    }
    // 初始化这个内存空间
    NdisZeroMemory(pOpenContext, sizeof(OPEN_CONTEXT));
    NdisAllocateSpinLock(&pOpenContext->Lock);
    NdisInitializeEvent(&pOpenContext->RequestEvent);
    pOpenContext->RefCount = 1;
    pOpenContext->pAdapt = pAdapt;
    return pOpenContext;
}
VOID DevRefOpenContext(POPEN_CONTEXT pOpenContext) 
{
    // 首先增加对适配器的引用，然后再增加OPEN_CONTEXT的引用计数
   PtRefAdapter(pOpenContext->pAdapt);
   NdisInterlockedIncrement(&pOpenContext->RefCount);
}
// 减少对打开环境的引用，如果减为0，则释放它占用的内存
VOID DevDerefOpenContext(POPEN_CONTEXT pOpenContext) 
{
   PADAPT pAdapt = NULL;
   if(pOpenContext == NULL)
       return;
   // 首先保存对应的适配器指针，以便后面对它调用PtDerefAdapter函数
   pAdapt = pOpenContext->pAdapt;
   // 减小引用计数，如果没有代码再引用它了，则清除资源
   if(NdisInterlockedDecrement(&pOpenContext->RefCount) == 0)
   {
      NdisFreeSpinLock(&pOpenContext->Lock);
      NdisFreeMemory(pOpenContext,sizeof(pOpenContext), 0);
   }
   // 减少对适配器的引用
   PtDerefAdapter(pAdapt);
}
VOID DevRequestComplete(PADAPT pAdapt, PNDIS_REQUEST NdisRequest,NDIS_STATUS Status)
{
    POPEN_CONTEXT pOpenContext = CONTAINING_RECORD(NdisRequest, OPEN_CONTEXT, Request);
    pOpenContext->RequestStatus = Status;
    NdisSetEvent(&pOpenContext->RequestEvent);
}

						