C/C++信息隐写术（三）之txt文件藏入BMP文件
这一节是基于第二节的代码。下面是第二节的链接
http://blog.csdn.net/qq78442761/article/details/54880328
这一节结束后，我们将把一个远控程序的客户端（潜伏者）放入BMP文件中。
现在我们来看这一节：之txt文件藏入BMP文件
我们先创建一个1.txt文件。文件里面保存了数据，如下图所示：
现在我来说明下程序的思路。
我们把这个txt文件用二进制的方式进行读取，然后写入BMP的alpha通道，就是这么简单的思路。
下面我们来看关键代码：
void CBMPHide::savetxtFile(char* FileName)
{
FILE* fp = fopen(FileName, "rb");
if (fp == NULL)
{
printf_s("文件打开失败\n");
return;
}
char buf[128]; //0xFF=255
int n = fread(buf, 1, 128, fp);
if (n == 0)
{
printf_s("文件为空，隐藏失败！");
return;
}
fclose(fp);
this->hideString2BMP(buf);
this->save();
}void CBMPHide::showtxtFile(char* szBmpFIleName/*=NULL*/)
{
string sDstFileName = "";
if (szBmpFIleName == 0)
{
sDstFileName = sBmpFileName + ".hide.bmp";
}
else
sDstFileName = szBmpFIleName;
HANDLE hfile = CreateFileA(sDstFileName.c_str(),
GENERIC_READ | GENERIC_WRITE,
FILE_SHARE_READ | FILE_SHARE_WRITE,
NULL,
OPEN_EXISTING, 0, 0);
if (hfile == INVALID_HANDLE_VALUE)
{
return;
}
DWORD dwSize = GetFileSize(hfile, 0);
LPBYTE pBuf1 = new byte[dwSize];
DWORD dwRead = 0;
ReadFile(hfile, pBuf1, dwSize, &dwRead, 0);
CloseHandle(hfile);
//文件内容读取到pBuf1中
BITMAPFILEHEADER *pHdr = (BITMAPFILEHEADER *)pBuf1;
LPBYTE pStr = pBuf1 + pHdr->bfOffBits + 3;
char szTmp[1280];
RtlZeroMemory(szTmp, 1280);
for (int i = 0; i < 1280; i++)
{
if (*pStr == 0 || *pStr == 0xFF ||*pStr == 0xCC)
{
break;
}
szTmp[i] = *pStr;
pStr += 4;
}
printf_s(szTmp);
const char* filename = "from bmp.txt";
FILE* fp = fopen(filename, "wb");
if (fp == NULL)
{
printf_s("txt文件保存失败!");
return;
}
fwrite(szTmp, 1, strlen(szTmp) , fp);
fclose(fp);
delete[]pBuf1;
}下面是程序源码打包下载：
http://download.csdn.net/detail/qq78442761/9748189
下面是运行结果：
下面是程序的所有代码：
dwBmpSize.h
#define _CRT_SECURE_NO_WARNINGS
#pragma once
#include
#include
using namespace std;
class CBMPHide
{
public:
CBMPHide();
~CBMPHide();
bool setBmpFileName(char* szFileName); //设置Bmp文件名
int getBmpWidth(); //获取宽度
int getBmpHeight(); //获取高度
int getBmpBitCount(); //获取Bit总数
bool save();
bool hideString2BMP(char* szStr2Hide); //隐藏String到BMP文件中
void showStringInBmp(char* szBmpFIleName=NULL); //展示
void savetxtFile(char* FileName); //隐藏txt文件到bmp图像中
void showtxtFile(char* szBmpFIleName = NULL); //解密出txtFile
private:
DWORD dwBmpSize; //图片文件大小
DWORD dwTxTSize;
string sBmpFileName;
string sTxTFileName;
LPBYTE pBuf; //用于存放图片信息的内存
LPBYTE ptxtBuf; //用于存放txt信息的内存
BITMAPFILEHEADER* m_fileHdr;
BITMAPINFOHEADER* m_infoHdr;
}; dwBmpSIze.cpp
#include "dwBmpSize.h"
CBMPHide::CBMPHide()
{
sBmpFileName = "";
pBuf = 0;
dwBmpSize = 0;
ptxtBuf = 0;
}
CBMPHide::~CBMPHide()
{
}
bool CBMPHide::setBmpFileName(char* szFileName)
{
this->sBmpFileName = szFileName;
if (pBuf) //如果已经生成就释放掉
{
delete[]pBuf;
}
HANDLE hfile = CreateFileA(szFileName, GENERIC_READ | GENERIC_WRITE, FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, 0);
if (hfile == INVALID_HANDLE_VALUE)
{
return false;
}
//和struct BITMAPFILEHEADER bmfh里面的 bfSize的大小应该是一样的。
dwBmpSize = GetFileSize(hfile, 0); //获取文件的大小
pBuf = new byte[dwBmpSize];
DWORD dwRead = 0;
ReadFile(hfile, pBuf, dwBmpSize, &dwRead, 0);
if (dwRead != dwBmpSize)
{
delete[]pBuf;
pBuf = 0;
return false;
}
CloseHandle(hfile);
m_fileHdr = (BITMAPFILEHEADER*)pBuf;
m_infoHdr = (BITMAPINFOHEADER*)(pBuf + sizeof(BITMAPFILEHEADER));
return true; //成功话就是文件的内容读取到pBuf里面
}
int CBMPHide::getBmpWidth()
{
return m_infoHdr->biWidth;
}
int CBMPHide::getBmpHeight()
{
return m_infoHdr->biHeight;
}
int CBMPHide::getBmpBitCount()
{
return m_infoHdr->biBitCount;
}
bool CBMPHide::save()
{
string sDstFileName = sBmpFileName + ".hide.bmp";
HANDLE hfile = CreateFileA(sDstFileName.c_str(),
GENERIC_READ | GENERIC_WRITE,
FILE_SHARE_READ | FILE_SHARE_WRITE,
NULL,
CREATE_ALWAYS, 0, 0);
if (hfile == INVALID_HANDLE_VALUE)
{
return false;
}
DWORD dwWritten = 0;
WriteFile(hfile, pBuf, dwBmpSize, &dwWritten, 0);
if (dwBmpSize != dwWritten)
{
return false;
}
CloseHandle(hfile);
return true;
}
//隐藏一个字符串到图片中，把字符串拆成字节，写入每个像素的alpha通道中
bool CBMPHide::hideString2BMP(char* szStr2Hide)
{
LPBYTE pAlpha = pBuf + m_fileHdr->bfOffBits + 3; //第一个像素的通道位置
int nHide; //成功隐藏的字节数
//每次循环写入一个字节，吸入alpha通道
//(pAlpha - pBuf) < m_fileHdr->bfSize这个是判断字符串是太大，图片不能隐藏
for (nHide = 0; (pAlpha - pBuf) < m_fileHdr->bfSize && szStr2Hide[nHide] != 0; nHide++, pAlpha += 4)
{
*pAlpha = szStr2Hide[nHide]; //写入一个字节
}
return true;
}
void CBMPHide::showStringInBmp(char* szBmpFIleName/*=NULL*/)
{
string sDstFileName="";
if (szBmpFIleName == 0)
{
sDstFileName = sBmpFileName + ".hide.bmp";
}
else
sDstFileName = szBmpFIleName;
HANDLE hfile = CreateFileA(sDstFileName.c_str(),
GENERIC_READ | GENERIC_WRITE,
FILE_SHARE_READ | FILE_SHARE_WRITE,
NULL,
OPEN_EXISTING, 0, 0);
if (hfile == INVALID_HANDLE_VALUE)
{
return;
}
DWORD dwSize = GetFileSize(hfile, 0);
LPBYTE pBuf1 = new byte[dwSize];
DWORD dwRead = 0;
ReadFile(hfile, pBuf1, dwSize, &dwRead, 0);
CloseHandle(hfile);
//文件内容读取到pBuf1中
BITMAPFILEHEADER *pHdr = (BITMAPFILEHEADER *)pBuf1;
LPBYTE pStr = pBuf1 + pHdr->bfOffBits + 3;
char szTmp[1280];
RtlZeroMemory(szTmp, 1280);
for (int i = 0; i < 1280; i++)
{
if (*pStr == 0 || *pStr == 0xFF)
{
break;
}
szTmp[i] = *pStr;
pStr += 4;
}
printf_s(szTmp);
delete[]pBuf1;
}
void CBMPHide::savetxtFile(char* FileName)
{
FILE* fp = fopen(FileName, "rb");
if (fp == NULL)
{
printf_s("文件打开失败\n");
return;
}
char buf[128]; //0xFF=255
int n = fread(buf, 1, 128, fp);
if (n == 0)
{
printf_s("文件为空，隐藏失败！");
return;
}
fclose(fp);
this->hideString2BMP(buf);
this->save();
}
void CBMPHide::showtxtFile(char* szBmpFIleName/*=NULL*/)
{
string sDstFileName = "";
if (szBmpFIleName == 0)
{
sDstFileName = sBmpFileName + ".hide.bmp";
}
else
sDstFileName = szBmpFIleName;
HANDLE hfile = CreateFileA(sDstFileName.c_str(),
GENERIC_READ | GENERIC_WRITE,
FILE_SHARE_READ | FILE_SHARE_WRITE,
NULL,
OPEN_EXISTING, 0, 0);
if (hfile == INVALID_HANDLE_VALUE)
{
return;
}
DWORD dwSize = GetFileSize(hfile, 0);
LPBYTE pBuf1 = new byte[dwSize];
DWORD dwRead = 0;
ReadFile(hfile, pBuf1, dwSize, &dwRead, 0);
CloseHandle(hfile);
//文件内容读取到pBuf1中
BITMAPFILEHEADER *pHdr = (BITMAPFILEHEADER *)pBuf1;
LPBYTE pStr = pBuf1 + pHdr->bfOffBits + 3;
char szTmp[1280];
RtlZeroMemory(szTmp, 1280);
for (int i = 0; i < 1280; i++)
{
if (*pStr == 0 || *pStr == 0xFF ||*pStr == 0xCC)
{
break;
}
szTmp[i] = *pStr;
pStr += 4;
}
printf_s(szTmp);
const char* filename = "from bmp.txt";
FILE* fp = fopen(filename, "wb");
if (fp == NULL)
{
printf_s("txt文件保存失败!");
return;
}
fwrite(szTmp, 1, strlen(szTmp) , fp);
fclose(fp);
delete[]pBuf1;
}
main.cpp
#include
#include "dwBmpSize.h"
int main()
{
CBMPHide hide;
hide.setBmpFileName("test.bmp");
printf_s("test.bmp width:%d,height:%d,bitCount%d\n",
hide.getBmpWidth(),
hide.getBmpHeight(),
hide.getBmpBitCount());
//hide.hideString2BMP("Hello Word");
//hide.save();
//hide.showStringInBmp("test.bmp.hide.bmp");
hide.savetxtFile("1.txt");
hide.showtxtFile("test.bmp.hide.bmp");
getchar();
return 0;
} 这一节结束后，我们将把一个远控程序的客户端（潜伏者）放入BMP文件中。