自实现getprocaddress（名称查找或者序号查找）

通过名称去找

// MyGETPRCOADDRESS.cpp : 此文件包含 "main" 函数。程序执行将在此处开始并结束。
//

#include 
#include

/*WINBASEAPI   //导出不需要使用，那么我们注释掉*/
FARPROC
WINAPI
MyGetProcAddress(
    _In_ HMODULE hModule,
    _In_ LPCSTR lpProcName
)

{
    PIMAGE_DOS_HEADER pIMAGE_DOS_HEADER = (PIMAGE_DOS_HEADER)hModule;
    PIMAGE_NT_HEADERS pIMAGE_NT_HEADERS = (PIMAGE_NT_HEADERS)(pIMAGE_DOS_HEADER->e_lfanew + (DWORD)hModule);   //NT头
    PIMAGE_EXPORT_DIRECTORY pIMAGE_EXPORT_DIRECTORYRVA = (PIMAGE_EXPORT_DIRECTORY)(pIMAGE_NT_HEADERS->OptionalHeader.DataDirectory[0].VirtualAddress);  //导出表项，获得RVA  RVA并不是真正的导出表项需要转VA，转VA需要加上image_base(也就是加载地址）

    PIMAGE_EXPORT_DIRECTORY pIMAGE_EXPORT_DIRECTORY = (PIMAGE_EXPORT_DIRECTORY)((DWORD)pIMAGE_EXPORT_DIRECTORYRVA + (DWORD)hModule);  //这个才是真正的VA，真正的导出表项，因为RVA在内存中是没有的

    DWORD ModuleName = pIMAGE_EXPORT_DIRECTORY->Name + (DWORD)hModule;
    printf("%s", ModuleName);
    return NULL;
}

int main()
{
    std::cout << "Hello World!\n";
    HMODULE Hmodule =  GetModuleHandleA("ntdll.dll");  //为了防止同名函数，所以先要获得哪个模块   那么Hmodule相当于模块基址
    //void *p = GetProcAddress(Hmodule, "RtlDispatchAPC");
    //void *p2 = GetProcAddress(Hmodule, (LPCSTR)1);
    void* p1 = MyGetProcAddress(Hmodule, "RtlDispatchAPC");
    printf("%s", p1);
}

// 运行程序: Ctrl + F5 或调试 >“开始执行(不调试)”菜单
// 调试程序: F5 或调试 >“开始调试”菜单

// 入门使用技巧: 
//   1. 使用解决方案资源管理器窗口添加/管理文件
//   2. 使用团队资源管理器窗口连接到源代码管理
//   3. 使用输出窗口查看生成输出和其他消息
//   4. 使用错误列表窗口查看错误
//   5. 转到“项目”>“添加新项”以创建新的代码文件，或转到“项目”>“添加现有项”以将现有代码文件添加到项目
//   6. 将来，若要再次打开此项目，请转到“文件”>“打开”>“项目”并选择 .sln 文件

可以看到找成功了

接下来获取名称表格

可以看到0x777727D4就是函数的地址，那么函数地址第一个就是0x0011626c，因为DWORD是4字节
但是还需要加基址hModule（0x77660000），那么就是0x0011626c+0x77660000，也就是如下

可以看到成功定位到了函数，那么可以正确获取到名称表格
然后我们写循环

for (size_t i = 0; i < pIMAGE_EXPORT_DIRECTORY->NumberOfNames; i++)
{
    DWORD FunNameRVA = NameAddress[i];
    char * FunName = (char *)(FunNameRVA + (DWORD)hModule);
    printf("%s\n", FunName);
}

#include 
#include

/*WINBASEAPI   //导出不需要使用，那么我们注释掉*/
FARPROC
WINAPI
MyGetProcAddress(
    _In_ HMODULE hModule,
    _In_ LPCSTR lpProcName
)

{
    PIMAGE_DOS_HEADER pIMAGE_DOS_HEADER = (PIMAGE_DOS_HEADER)hModule;
    PIMAGE_NT_HEADERS pIMAGE_NT_HEADERS = (PIMAGE_NT_HEADERS)(pIMAGE_DOS_HEADER->e_lfanew + (DWORD)hModule);   //NT头
    PIMAGE_EXPORT_DIRECTORY pIMAGE_EXPORT_DIRECTORYRVA = (PIMAGE_EXPORT_DIRECTORY)(pIMAGE_NT_HEADERS->OptionalHeader.DataDirectory[0].VirtualAddress);  //导出表项，获得RVA  RVA并不是真正的导出表项需要转VA，转VA需要加上image_base(也就是加载地址）

    PIMAGE_EXPORT_DIRECTORY pIMAGE_EXPORT_DIRECTORY = (PIMAGE_EXPORT_DIRECTORY)((DWORD)pIMAGE_EXPORT_DIRECTORYRVA + (DWORD)hModule);  //这个才是真正的VA，真正的导出表项，因为RVA在内存中是没有的

    DWORD ModuleName = pIMAGE_EXPORT_DIRECTORY->Name + (DWORD)hModule;
    //printf("%s", ModuleName);
    DWORD NameAddressRVA = pIMAGE_EXPORT_DIRECTORY->AddressOfNames;
    DWORD* NameAddress = (DWORD *)(NameAddressRVA + (DWORD)hModule);
    for (size_t i = 0; i < pIMAGE_EXPORT_DIRECTORY->NumberOfNames; i++)
    {
        DWORD FunNameRVA = NameAddress[i];
        char * FunName = (char *)(FunNameRVA + (DWORD)hModule);
        printf("%s\n", FunName);
    }
    printf("%s\n", ModuleName);
    return NULL;
}

int main()
{
    std::cout << "Hello World!\n";
    HMODULE Hmodule =  GetModuleHandleA("ntdll.dll");
    //void *p = GetProcAddress(Hmodule, "RtlDispatchAPC");
    //void *p2 = GetProcAddress(Hmodule, (LPCSTR)1);
    void* p1 = MyGetProcAddress(Hmodule, "RtlDispatchAPC");
    printf("%s", p1);
}

但是这样写看着有点不舒服，那么我们写一个RVA转AV的函数，让整体代码看起来舒服点

可以看到再次运行可以成功输出相同的结果

#include 
#include

/*WINBASEAPI   //导出不需要使用，那么我们注释掉*/
DWORD RVTTOVA(DWORD RVA, DWORD hMODULE) {
    return RVA + hMODULE;
}

FARPROC
WINAPI
MyGetProcAddress(
    _In_ HMODULE hModule,
    _In_ LPCSTR lpProcName
)

{
    PIMAGE_DOS_HEADER pIMAGE_DOS_HEADER = (PIMAGE_DOS_HEADER)hModule;
    PIMAGE_NT_HEADERS pIMAGE_NT_HEADERS = (PIMAGE_NT_HEADERS)(pIMAGE_DOS_HEADER->e_lfanew + (DWORD)hModule);   //NT头
    PIMAGE_EXPORT_DIRECTORY pIMAGE_EXPORT_DIRECTORYRVA = (PIMAGE_EXPORT_DIRECTORY)(pIMAGE_NT_HEADERS->OptionalHeader.DataDirectory[0].VirtualAddress);  //导出表项，获得RVA  RVA并不是真正的导出表项需要转VA，转VA需要加上image_base(也就是加载地址）

    PIMAGE_EXPORT_DIRECTORY pIMAGE_EXPORT_DIRECTORY = (PIMAGE_EXPORT_DIRECTORY)RVTTOVA((DWORD)pIMAGE_EXPORT_DIRECTORYRVA,(DWORD)hModule);  //这个才是真正的VA，真正的导出表项，因为RVA在内存中是没有的

    //DWORD ModuleName = pIMAGE_EXPORT_DIRECTORY->Name + (DWORD)hModule;
    DWORD ModuleName =  RVTTOVA(pIMAGE_EXPORT_DIRECTORY->Name, (DWORD)hModule);
    //printf("%s", ModuleName);
 /*   DWORD NameAddressRVA = pIMAGE_EXPORT_DIRECTORY->AddressOfNames;
    DWORD* NameAddress = (DWORD *)(NameAddressRVA + (DWORD)hModule);*/
    DWORD* NameAddress = (DWORD*)RVTTOVA(pIMAGE_EXPORT_DIRECTORY->AddressOfNames, (DWORD)hModule);
    for (size_t i = 0; i < pIMAGE_EXPORT_DIRECTORY->NumberOfNames; i++)
    {
        //DWORD FunNameRVA = NameAddress[i];
        //char * FunName = (char *)(FunNameRVA + (DWORD)hModule);
        char* FunName = (char*)RVTTOVA(NameAddress[i], (DWORD)hModule);
        printf("%s\n", FunName);
    }
    printf("%s\n", ModuleName);
    return NULL;
}

int main()
{
    std::cout << "Hello World!\n";
    HMODULE Hmodule =  GetModuleHandleA("ntdll.dll");
    //void *p = GetProcAddress(Hmodule, "RtlDispatchAPC");
    //void *p2 = GetProcAddress(Hmodule, (LPCSTR)1);
    void* p1 = MyGetProcAddress(Hmodule, "RtlDispatchAPC");
    printf("%x", p1);
}

最后输出的0这里有问题，是因为需要我们改成printf打印p而不是p1，要进行对比

注意之前的自定义函数名写错了，应该是RVATOVA，因为是RVA转VA，之前写的没注意到

然后我们写导出函数名称序号表

//导出函数名称序号表
DWORD* NameOrdinalAddress = (DWORD*)RVATOVA(pIMAGE_EXPORT_DIRECTORY->AddressOfNameOrdinals, (DWORD)hModule);

可以看到显示出了序号，发现是二字节而不是四字节，那么我们就不能用DWORD了要用二字节的WORD
那么我们打印序号，接下来写导出函数地址表，都写在一块了

//导出函数名称序号表
WORD* NameOrdinalAddress = (WORD*)RVATOVA(pIMAGE_EXPORT_DIRECTORY->AddressOfNameOrdinals, (DWORD)hModule);
//导出函数地址表
DWORD* AddressFun = (DWORD*)RVATOVA(pIMAGE_EXPORT_DIRECTORY->AddressOfFunctions, (DWORD)hModule);

for (size_t i = 0; i < pIMAGE_EXPORT_DIRECTORY->NumberOfNames; i++)
{
    //DWORD FunNameRVA = NameAddress[i];
    //char * FunName = (char *)(FunNameRVA + (DWORD)hModule);
    char* FunName = (char*)RVATOVA(NameAddress[i], (DWORD)hModule);
    if (strcmp(FunName,lpProcName) == 0)
    {
        printf("%d\n",NameOrdinalAddress[i] + pIMAGE_EXPORT_DIRECTORY->Base);
        printf("%x\n", RVATOVA(AddressFun[NameOrdinalAddress[i]],(DWORD)hModule));
        printf("找到了！");
    }

    //printf("%s\n", FunName);
}
printf("%s\n", ModuleName);
return NULL;
}

试试wcsspn函数

试试RtlDispatchAPC函数

可以看到对比序号都一样，说明没有序号找错

总结

那么这里来总结下，总共四步骤
1.导出表
2.导出函数名称表
3.导出函数名称序号表
4.导出函数地址表

完整代码：

#include 
#include

/*WINBASEAPI   //导出不需要使用，那么我们注释掉*/
DWORD RVATOVA(DWORD RVA, DWORD hMODULE) {
    return RVA + hMODULE;
}

FARPROC
WINAPI
MyGetProcAddress(
    _In_ HMODULE hModule,
    _In_ LPCSTR lpProcName
)

{
    PIMAGE_DOS_HEADER pIMAGE_DOS_HEADER = (PIMAGE_DOS_HEADER)hModule;
    PIMAGE_NT_HEADERS pIMAGE_NT_HEADERS = (PIMAGE_NT_HEADERS)(pIMAGE_DOS_HEADER->e_lfanew + (DWORD)hModule);   //NT头
    PIMAGE_EXPORT_DIRECTORY pIMAGE_EXPORT_DIRECTORYRVA = (PIMAGE_EXPORT_DIRECTORY)(pIMAGE_NT_HEADERS->OptionalHeader.DataDirectory[0].VirtualAddress);  //导出表项，获得RVA  RVA并不是真正的导出表项需要转VA，转VA需要加上image_base(也就是加载地址）

    //导出表
    PIMAGE_EXPORT_DIRECTORY pIMAGE_EXPORT_DIRECTORY = (PIMAGE_EXPORT_DIRECTORY)RVATOVA((DWORD)pIMAGE_EXPORT_DIRECTORYRVA,(DWORD)hModule);  //这个才是真正的VA，真正的导出表项，因为RVA在内存中是没有的

    //DWORD ModuleName = pIMAGE_EXPORT_DIRECTORY->Name + (DWORD)hModule;
    DWORD ModuleName =  RVATOVA(pIMAGE_EXPORT_DIRECTORY->Name, (DWORD)hModule);
    //printf("%s", ModuleName);
 /*   DWORD NameAddressRVA = pIMAGE_EXPORT_DIRECTORY->AddressOfNames;
    DWORD* NameAddress = (DWORD *)(NameAddressRVA + (DWORD)hModule);*/
    //导出函数名称表
    DWORD* NameAddress = (DWORD*)RVATOVA(pIMAGE_EXPORT_DIRECTORY->AddressOfNames, (DWORD)hModule);

    //导出函数名称序号表
    WORD* NameOrdinalAddress = (WORD*)RVATOVA(pIMAGE_EXPORT_DIRECTORY->AddressOfNameOrdinals, (DWORD)hModule);

    //导出函数地址表
    DWORD* AddressFun = (DWORD*)RVATOVA(pIMAGE_EXPORT_DIRECTORY->AddressOfFunctions, (DWORD)hModule);

   

    for (size_t i = 0; i < pIMAGE_EXPORT_DIRECTORY->NumberOfNames; i++)
    {
        //DWORD FunNameRVA = NameAddress[i];
        //char * FunName = (char *)(FunNameRVA + (DWORD)hModule);
        char* FunName = (char*)RVATOVA(NameAddress[i], (DWORD)hModule);
        if (strcmp(FunName,lpProcName) == 0)
        {
            printf("%d\n",NameOrdinalAddress[i] + pIMAGE_EXPORT_DIRECTORY->Base);
            printf("%x\n", RVATOVA(AddressFun[NameOrdinalAddress[i]],(DWORD)hModule));
            printf("找到了！");
        }
  
        //printf("%s\n", FunName);
    }
    printf("%s\n", ModuleName);
    return NULL;
}

int main()
{
    std::cout << "Hello World!\n";
    HMODULE Hmodule =  GetModuleHandleA("ntdll.dll");
    void *p = GetProcAddress(Hmodule, "RtlDispatchAPC");
    //void *p2 = GetProcAddress(Hmodule, (LPCSTR)1);
    void* p1 = MyGetProcAddress(Hmodule, "RtlDispatchAPC");
    printf("%x", p);
}

通过序号去找

以刚才的例子，这里通过刚才得到的8去获取名称
反汇编代码看1是比较是否大于FFFF，如果大于就跳到字符串，小于就跳到序号
比如8，就需要8-base才是获得的
可以看到自定义的序号查找也找到了

#include 
#include

/*WINBASEAPI   //导出不需要使用，那么我们注释掉*/
DWORD RVATOVA(DWORD RVA, DWORD hMODULE) {
    return RVA + hMODULE;
}

//FARPROC
//WINAPI
//MyGetProcAddress(
//    _In_ HMODULE hModule,
//    _In_ LPCSTR lpProcName
//)
FARPROC
WINAPI
MyOrdinalGetProcAddress(
    _In_ HMODULE hModule,
    _In_ LPCSTR lpProcName
)

{
    PIMAGE_DOS_HEADER pIMAGE_DOS_HEADER = (PIMAGE_DOS_HEADER)hModule;
    PIMAGE_NT_HEADERS pIMAGE_NT_HEADERS = (PIMAGE_NT_HEADERS)(pIMAGE_DOS_HEADER->e_lfanew + (DWORD)hModule);   //NT头
    PIMAGE_EXPORT_DIRECTORY pIMAGE_EXPORT_DIRECTORYRVA = (PIMAGE_EXPORT_DIRECTORY)(pIMAGE_NT_HEADERS->OptionalHeader.DataDirectory[0].VirtualAddress);  //导出表项，获得RVA  RVA并不是真正的导出表项需要转VA，转VA需要加上image_base(也就是加载地址）

    //导出表
    PIMAGE_EXPORT_DIRECTORY pIMAGE_EXPORT_DIRECTORY = (PIMAGE_EXPORT_DIRECTORY)RVATOVA((DWORD)pIMAGE_EXPORT_DIRECTORYRVA,(DWORD)hModule);  //这个才是真正的VA，真正的导出表项，因为RVA在内存中是没有的

    //导出函数地址表
    DWORD* AddressFun = (DWORD*)RVATOVA(pIMAGE_EXPORT_DIRECTORY->AddressOfFunctions, (DWORD)hModule);
    DWORD dwBase = pIMAGE_EXPORT_DIRECTORY->Base;
    DWORD funAddress =  RVATOVA( AddressFun[(DWORD)lpProcName - dwBase],(DWORD)hModule);
    printf("%x\n", funAddress);


    return NULL;
}

int main()
{
    std::cout << "Hello World!\n";
    HMODULE Hmodule =  GetModuleHandleA("ntdll.dll");
    void *p = GetProcAddress(Hmodule, "RtlDispatchAPC");
    void *p2 = GetProcAddress(Hmodule, (LPCSTR)8);
    void* p1 = MyOrdinalGetProcAddress(Hmodule, (LPCSTR)8);
    printf("%x", p1);
    printf("%x", p2);
}

以上是找到了该函数，那么我们通过strcmp函数来获得该函数

#include 
#include

/*WINBASEAPI   //导出不需要使用，那么我们注释掉*/
//FARPROC
//WINAPI
DWORD MyGetProcAddress(
    _In_ HMODULE hModule,
    _In_ LPCSTR lpProcName
)

{
    PIMAGE_DOS_HEADER pIMAGE_DOS_HEADER = (PIMAGE_DOS_HEADER)hModule;
    PIMAGE_NT_HEADERS pIMAGE_NT_HEADERS = (PIMAGE_NT_HEADERS)(pIMAGE_DOS_HEADER->e_lfanew + (DWORD)hModule);   //NT头
    PIMAGE_EXPORT_DIRECTORY pIMAGE_EXPORT_DIRECTORYRVA = (PIMAGE_EXPORT_DIRECTORY)(pIMAGE_NT_HEADERS->OptionalHeader.DataDirectory[0].VirtualAddress);  //导出表项，获得RVA  RVA并不是真正的导出表项需要转VA，转VA需要加上image_base(也就是加载地址）

    PIMAGE_EXPORT_DIRECTORY pIMAGE_EXPORT_DIRECTORY = (PIMAGE_EXPORT_DIRECTORY)((DWORD)pIMAGE_EXPORT_DIRECTORYRVA + (DWORD)hModule);  //这个才是真正的VA，真正的导出表项，因为RVA在内存中是没有的

    DWORD ModuleName = pIMAGE_EXPORT_DIRECTORY->Name + (DWORD)hModule;
    //可以看到底下地址都需要写成指针形式
    DWORD *pAddressOfFunction = (DWORD*)(pIMAGE_EXPORT_DIRECTORY->AddressOfFunctions + (DWORD)hModule);
    //printf("%s", ModuleName);
    DWORD *NameAddress = (DWORD*)(pIMAGE_EXPORT_DIRECTORY->AddressOfNames + (DWORD)hModule);
    WORD* pAddressOfNameOrdinals = (WORD*)(pIMAGE_EXPORT_DIRECTORY->AddressOfNameOrdinals + (DWORD)hModule);

    for (size_t i = 0; i < pIMAGE_EXPORT_DIRECTORY->NumberOfNames; i++)
    {
        DWORD FunNameRVA = NameAddress[i];
        char* FunName = (char*)(FunNameRVA + (DWORD)hModule);
        if (strcmp(lpProcName, FunName) == 0)
        {
            return (pAddressOfFunction[pAddressOfNameOrdinals[i]] + (DWORD)hModule);
        }
        printf("%s\n", FunName);
    }
    printf("%s\n", ModuleName);
    return NULL;
}

int main()
{
    std::cout << "Hello World!\n";
    HMODULE Hmodule = GetModuleHandleA("ntdll.dll");
    //void *p = GetProcAddress(Hmodule, "RtlDispatchAPC");
    //void *p2 = GetProcAddress(Hmodule, (LPCSTR)1);
    DWORD p1 = MyGetProcAddress(Hmodule, "RtlDispatchAPC");
    printf("%s", p1);
}

可以看到成功获得函数

这里我们要获得的是Kernel32.dll里的CreateFileA函数

#include 
#include

/*WINBASEAPI   //导出不需要使用，那么我们注释掉*/
//FARPROC
//WINAPI
DWORD MyGetProcAddress(
    _In_ HMODULE hModule,
    _In_ LPCSTR lpProcName
)

{
    PIMAGE_DOS_HEADER pIMAGE_DOS_HEADER = (PIMAGE_DOS_HEADER)hModule;
    PIMAGE_NT_HEADERS pIMAGE_NT_HEADERS = (PIMAGE_NT_HEADERS)(pIMAGE_DOS_HEADER->e_lfanew + (DWORD)hModule);   //NT头
    PIMAGE_EXPORT_DIRECTORY pIMAGE_EXPORT_DIRECTORYRVA = (PIMAGE_EXPORT_DIRECTORY)(pIMAGE_NT_HEADERS->OptionalHeader.DataDirectory[0].VirtualAddress);  //导出表项，获得RVA  RVA并不是真正的导出表项需要转VA，转VA需要加上image_base(也就是加载地址）

    PIMAGE_EXPORT_DIRECTORY pIMAGE_EXPORT_DIRECTORY = (PIMAGE_EXPORT_DIRECTORY)((DWORD)pIMAGE_EXPORT_DIRECTORYRVA + (DWORD)hModule);  //这个才是真正的VA，真正的导出表项，因为RVA在内存中是没有的

    DWORD ModuleName = pIMAGE_EXPORT_DIRECTORY->Name + (DWORD)hModule;
    //可以看到底下地址都需要写成指针形式
    DWORD *pAddressOfFunction = (DWORD*)(pIMAGE_EXPORT_DIRECTORY->AddressOfFunctions + (DWORD)hModule);
    //printf("%s", ModuleName);
    DWORD *NameAddress = (DWORD*)(pIMAGE_EXPORT_DIRECTORY->AddressOfNames + (DWORD)hModule);
    WORD* pAddressOfNameOrdinals = (WORD*)(pIMAGE_EXPORT_DIRECTORY->AddressOfNameOrdinals + (DWORD)hModule);




    for (size_t i = 0; i < pIMAGE_EXPORT_DIRECTORY->NumberOfNames; i++)
    {
        DWORD FunNameRVA = NameAddress[i];
        char* FunName = (char*)(FunNameRVA + (DWORD)hModule);
        if (strcmp(lpProcName, FunName) == 0)
        {
            return (pAddressOfFunction[pAddressOfNameOrdinals[i]] + (DWORD)hModule);
        }
        printf("%s\n", FunName);
    }
    printf("%s\n", ModuleName);
    return NULL;
}

int main()
{
    std::cout << "Hello World!\n";
    HMODULE Hmodule = GetModuleHandleA("Kernel32.dll");
    //void *p = GetProcAddress(Hmodule, "RtlDispatchAPC");
    //void *p2 = GetProcAddress(Hmodule, (LPCSTR)1);
    DWORD p1 = MyGetProcAddress(Hmodule, "CreateFileA");

    printf("%s", p1);
}

这里获得的是地址，之后调用需要转换成函数形式