base64.cpp

各种加密算法的集合

#include "pch.h" 
#include "base64.h" 
 
NAMESPACE_BEGIN(CryptoPP) 
 
static const int MAX_LINE_LENGTH = 72; 
 
static const byte vec[] = 
		"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; 
static const byte padding = '='; 
    
Base64Encoder::Base64Encoder(BufferedTransformation *outQueue, bool insertLineBreak) 
	: insertLineBreak(insertLineBreak), Filter(outQueue) 
{ 
	inBufSize=0; 
	lineLength=0; 
} 
 
void Base64Encoder::LineBreak() 
{ 
	if (insertLineBreak) 
		outQueue->Put('\n'); 
	lineLength=0; 
} 
 
void Base64Encoder::EncodeQuantum() 
{ 
	byte out; 
 
	out=(inBuf[0] & 0xFC) >> 2; 
	outQueue->Put(vec[out]); 
 
	out=((inBuf[0] & 0x03) << 4) | (inBuf[1] >> 4); 
	outQueue->Put(vec[out]); 
 
	out=((inBuf[1] & 0x0F) << 2) | (inBuf[2] >> 6); 
	outQueue->Put(inBufSize > 1 ? vec[out] : padding); 
 
	out=inBuf[2] & 0x3F; 
	outQueue->Put(inBufSize > 2 ? vec[out] : padding); 
 
	inBufSize=0; 
	lineLength+=4; 
 
	if (lineLength>=MAX_LINE_LENGTH) 
		LineBreak(); 
} 
 
void Base64Encoder::Put(const byte *inString, unsigned int length) 
{ 
	while (length--) 
		Base64Encoder::Put(*inString++); 
} 
 
void Base64Encoder::InputFinished() 
{ 
	if (inBufSize) 
	{ 
		for (int i=inBufSize;i<3;i++) 
			inBuf[i]=0; 
		EncodeQuantum(); 
	} 
 
	if (lineLength) // force a line break unless the current line is empty 
		LineBreak(); 
} 
 
Base64Decoder::Base64Decoder(BufferedTransformation *outQueue) 
	: Filter(outQueue) 
{ 
	inBufSize=0; 
} 
 
void Base64Decoder::DecodeQuantum() 
{ 
	byte out; 
 
	out = (inBuf[0] << 2) | (inBuf[1] >> 4); 
	outQueue->Put(out); 
 
	out = (inBuf[1] << 4) | (inBuf[2] >> 2); 
	if (inBufSize > 2) outQueue->Put(out); 
 
	out = (inBuf[2] << 6) | inBuf[3]; 
	if (inBufSize > 3) outQueue->Put(out); 
 
	inBufSize=0; 
} 
 
int Base64Decoder::ConvToNumber(byte inByte) 
{ 
	if (inByte >= 'A' && inByte <= 'Z') 
		return (inByte - 'A'); 
 
	if (inByte >= 'a' && inByte <= 'z') 
		return (inByte - 'a' + 26); 
 
	if (inByte >= '0' && inByte <= '9') 
		return (inByte - '0' + 52); 
 
	if (inByte == '+') 
		return (62); 
 
	if (inByte == '/') 
		return (63); 
 
	return (-1); 
} 
 
void Base64Decoder::Put(const byte *inString, unsigned int length) 
{ 
	while (length--) 
		Base64Decoder::Put(*inString++); 
} 
 
void Base64Decoder::InputFinished() 
{ 
	if (inBufSize) 
	{ 
		for (int i=inBufSize;i<4;i++) 
			inBuf[i]=0; 
		DecodeQuantum(); 
	} 
} 
 
NAMESPACE_END