Base64加解密C++

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我是靠谱客的博主天真春天，最近开发中收集的这篇文章主要介绍Base64加解密C++，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

BASE64.CPP

#include "BASE64.h"    

static const CHAR* DATA_BIN2ASCII = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";    

INT BASE64_Encode( const BYTE* inputBuffer, INT inputCount, TCHAR* outputBuffer )    
{    
	INT i;    
	BYTE b0, b1, b2;    

	if( (inputBuffer == NULL) || (inputCount < 0) )    
	{    
		return -1;  // 参数错误    
	}    

	if( outputBuffer != NULL )    
	{    
		for( i = inputCount; i > 0; i -= 3 )    
		{    
			if( i >= 3 )    
			{   // 将3字节数据转换成4个ASCII字符    
				b0 = *inputBuffer++;    
				b1 = *inputBuffer++;    
				b2 = *inputBuffer++;    

				*outputBuffer++ = DATA_BIN2ASCII[b0 >> 2];    
				*outputBuffer++ = DATA_BIN2ASCII[((b0 << 4) | (b1 >> 4)) & 0x3F];    
				*outputBuffer++ = DATA_BIN2ASCII[((b1 << 2) | (b2 >> 6)) & 0x3F];    
				*outputBuffer++ = DATA_BIN2ASCII[b2 & 0x3F];    
			}    
			else    
			{    
				b0 = *inputBuffer++;    
				if( i == 2 )b1 = *inputBuffer++; else b1 = 0;    

				*outputBuffer++ = DATA_BIN2ASCII[b0 >> 2];    
				*outputBuffer++ = DATA_BIN2ASCII[((b0 << 4) | (b1 >> 4)) & 0x3F];    
				*outputBuffer++ = (i == 1) ? TEXT('=') : DATA_BIN2ASCII[(b1 << 2) & 0x3F];    
				*outputBuffer++ = TEXT('=');    
			}    
		} // End for i    

		*outputBuffer++ = TEXT('/0');   // 添加字符串结束标记    
	}    

	return ((inputCount + 2) / 3) * 4;  // 返回有效字符个数    
}    

#define B64_EOLN            0xF0    // 换行/n    
#define B64_CR              0xF1    // 回车/r    
#define B64_EOF             0xF2    // 连字符-    
#define B64_WS              0xE0    // 跳格或者空格（/t、space）    
#define B64_ERROR           0xFF    // 错误字符    
#define B64_NOT_BASE64(a)   (((a)|0x13) == 0xF3)    

static const BYTE DATA_ASCII2BIN[128] = {    
	0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xE0,0xF0,0xFF,0xFF,0xF1,0xFF,0xFF,    
	0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,    
	0xE0,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x3E,0xFF,0xF2,0xFF,0x3F,    
	0x34,0x35,0x36,0x37,0x38,0x39,0x3A,0x3B,0x3C,0x3D,0xFF,0xFF,0xFF,0x00,0xFF,0xFF,    
	0xFF,0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x0A,0x0B,0x0C,0x0D,0x0E,    
	0x0F,0x10,0x11,0x12,0x13,0x14,0x15,0x16,0x17,0x18,0x19,0xFF,0xFF,0xFF,0xFF,0xFF,    
	0xFF,0x1A,0x1B,0x1C,0x1D,0x1E,0x1F,0x20,0x21,0x22,0x23,0x24,0x25,0x26,0x27,0x28,    
	0x29,0x2A,0x2B,0x2C,0x2D,0x2E,0x2F,0x30,0x31,0x32,0x33,0xFF,0xFF,0xFF,0xFF,0xFF    
};    

INT BASE64_Decode( const TCHAR* inputBuffer, INT inputCount, BYTE* outputBuffer )    
{    
	INT i, j;    
	BYTE b[4];    
	TCHAR ch;    

	if( (inputBuffer == NULL) || (inputCount < 0) )    
	{    
		return -1;  // 参数错误    
	}    

	// 去除头部空白字符    
	while( inputCount > 0 )    
	{    
		ch = *inputBuffer;    
		if( (ch < 0) || (ch >= 0x80) ) //base64码表只有0-64，怎么到80了，多了回车换行？   
		{    
			return -2;  // 数据错误，不在ASCII字符编码范围内    
		}    
		else    
		{    
			if( DATA_ASCII2BIN[ch] == B64_WS )    
			{    
				inputBuffer++;    
				inputCount--;    
			}    
			else    
			{    
				break;    
			}    
		}    
	}    

	// 去除尾部的空白字符、回车换行字符、连字符    
	while( inputCount >= 4 )    
	{    
		ch = inputBuffer[inputCount - 1];    
		if( (ch < 0) || (ch >= 0x80) )    
		{    
			return -2;  // 数据错误，不在ASCII字符编码范围内    
		}    
		else    
		{    
			if( B64_NOT_BASE64(DATA_ASCII2BIN[ch]) )    
			{    
				inputCount--;    
			}    
			else    
			{    
				break;    
			}    
		}    
	}    

	// 字符串长度必须为4的倍数    
	if( (inputCount % 4) != 0 )    
	{    
		return -2;  // 数据错误    
	}    

	if( outputBuffer != NULL )    
	{    
		for( i = 0; i < inputCount; i += 4 )    
		{    
			for( j = 0; j < 4; j++ )    
			{    
				ch = *inputBuffer++;    
				if( (ch < 0) || (ch >= 0x80) )    
				{    
					return -2;  // 数据错误，不在ASCII字符编码范围内    
				}    
				else    
				{    
					if( ch == '=' ) // 发现BASE64编码中的填充字符    
					{    
						break;    
					}    
					else    
					{    
						b[j] = DATA_ASCII2BIN[ch];    
						if( b[j] & 0x80 )    
						{    
							return -2;  // 数据错误，无效的Base64编码字符    
						}    
					}                       
				}    
			} // End for j    

			if( j == 4 )    
			{    
				*outputBuffer++ = (b[0] << 2) | (b[1] >> 4);    
				*outputBuffer++ = (b[1] << 4) | (b[2] >> 2 );    
				*outputBuffer++ = (b[2] << 6) | b[3];    
			}    
			else if( j == 3 )    
			{   // 有1个填充字节    
				*outputBuffer++ = (b[0] << 2) | (b[1] >> 4);    
				*outputBuffer++ = (b[1] << 4) | (b[2] >> 2 );    

				return (i >> 2) * 3 + 2;    
			}    
			else if( j == 2 )    
			{   // 有2个填充字节    
				*outputBuffer++ = (b[0] << 2) | (b[1] >> 4);    

				return (i >> 2) * 3 + 1;    
			}    
			else    
			{    
				return -2;  // 数据错误，无效的Base64编码字符    
			}               
		}   // End for i    
	}    

	return (inputCount >> 2) * 3;    
}

BASE64.h

 
#pragma once    
    
#include <windows.h>    
    
#ifdef  __cplusplus    
extern "C" {    
#endif    
    
/*  
功能：将二进制数据转换成BASE64编码字符串  
参数说明：  
    inputBuffer：要编码的二进制数据  
    inputCount：数据长度  
    outputBuffer：存储转换后的BASE64编码字符串  
返回值：  
     -1：参数错误  
    >=0：有效编码长度（字符数）,不包括字符串结束符。  
备注：  
    等效于openssl中EVP_EncodeBlock函数  
*/    
INT BASE64_Encode( const BYTE* inputBuffer, INT inputCount, TCHAR* outputBuffer );    
    
/*  
功能：将BASE64编码字符串转换为二进制数据  
参数说明：  
    inputBuffer：BASE64编码字符串  
    inputCount：编码长度（字符数）,应该为4的倍数。  
    outputBuffer：存储转换后的二进制数据  
返回值：  
     -1：参数错误  
     -2：数据错误  
    >=0：转换后的字节数  
备注：  
    等效于openssl中EVP_DecodeBlock函数  
*/    
INT BASE64_Decode( const TCHAR* inputBuffer, INT inputCount, BYTE* outputBuffer );    
    
#ifdef  __cplusplus    
}    
#endif

加密调用：

BOOL FieldEncrypt( CString strFieldName,CString &strResult)
{
	CHAR* chTemp = WideChartoUTF8(strFieldName.GetBuffer());
	string strRet(chTemp);
	delete [] chTemp;
	
	int nCount = strlen(strRet.c_str());
	int nDes = 0;
	if (nCount%3 == 0)
	{
		nDes = nCount/3*4;
	}
	else
	{
		nDes = (nCount/3 +1)*4;
	}
	TCHAR* chData = new TCHAR[nDes+2];
	ZeroMemory(chData,(nDes+2)*sizeof(TCHAR));
	BASE64_Encode((BYTE*)strRet.c_str(),nCount,chData);
	
	strResult = chData;

	if (NULL != chData)
	{
		delete chData;
		chData = NULL;
	}
	return TRUE;
}
CHAR* WideChartoUTF8(const wchar_t* pwzData)
{
	if (NULL == pwzData)
	{
		return NULL;
	}

	INT nLen = WideCharToMultiByte(CP_UTF8, 0, pwzData, -1, NULL, 0, NULL, NULL );
	if (nLen <= 0)
	{
		return NULL;
	}

	CHAR* pUtf8Rtn = new CHAR[nLen + 1];
	if (NULL == pUtf8Rtn)
	{
		return NULL;
	}
	memset(pUtf8Rtn, 0, nLen + 1);
	WideCharToMultiByte( CP_UTF8, 0, pwzData, -1, pUtf8Rtn, nLen, NULL, NULL );

	return pUtf8Rtn;
}