/*
* Copyright (C) 2012 Yee Young Han (http://blog.naver.com/websearch)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "Base64.h"
#include
#include
#include
static char garrBase64Table[] =
{ 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/', '\0'
};
static char gcBase64Pad = '=';
/**
* @ingroup SipPlatform
* @brief plain text 를 base64 문자열로 변환하였을 때의 base64 문자열의 길이를 리턴한다.
* @param iLength plain text 문자열
* @return base64 문자열의 길이를 리턴한다.
*/
int GetBase64EncodeLength( int iLength )
{
return ((iLength + 3 - iLength % 3) * 4 / 3 + 1);
}
/**
* @ingroup SipPlatform
* @brief base64 문자열을 plain text 로 변환하였을 때에 plain text 의 길이를 리턴한다.
* @param iLength base64 문자열의 길이
* @return plain text 문자열의 길이를 리턴한다.
*/
int GetBase64DecodeLength( int iLength )
{
return( (iLength / 4 * 3 + 1) * sizeof(char) );
}
/**
* @ingroup SipPlatform
* @brief plain text 를 base64 문자열로 변환한다.
* @param pszInput plain text 문자열
* @param iInputLength plain text 문자열의 길이
* @param pszOutput base64 문자열 저장 변수
* @param iOutputLength base64 문자열 저장 변수의 크기
* @return 성공하면 base64 문자열의 길이를 리턴하고 실패하면 -1 을 리턴한다.
*/
int Base64Encode( const char * pszInput, int iInputLength, char * pszOutput, int iOutputLength )
{
const unsigned char *pszCurrent = (const unsigned char *)pszInput;
unsigned char * pszResult = (unsigned char *)pszOutput;
int i = 0;
if( pszResult == NULL ) return -1;
if( iOutputLength < GetBase64EncodeLength( iInputLength )) return -1;
while( iInputLength > 2 )
{
pszResult[i++] = garrBase64Table[pszCurrent[0] >> 2];
pszResult[i++] = garrBase64Table[((pszCurrent[0] & 0x03) << 4) + (pszCurrent[1] >> 4)];
pszResult[i++] = garrBase64Table[((pszCurrent[1] & 0x0f) << 2) + (pszCurrent[2] >> 6)];
pszResult[i++] = garrBase64Table[pszCurrent[2] & 0x3f];
pszCurrent += 3;
iInputLength -= 3;
}
if( iInputLength != 0 )
{
pszResult[i++] = garrBase64Table[pszCurrent[0] >> 2];
if( iInputLength > 1 )
{
pszResult[i++] = garrBase64Table[((pszCurrent[0] & 0x03) << 4) + (pszCurrent[1] >> 4)];
pszResult[i++] = garrBase64Table[(pszCurrent[1] & 0x0f) << 2];
pszResult[i++] = gcBase64Pad;
}
else
{
pszResult[i++] = garrBase64Table[(pszCurrent[0] & 0x03) << 4];
pszResult[i++] = gcBase64Pad;
pszResult[i++] = gcBase64Pad;
}
}
pszResult[i] = '\0';
return i;
}
/**
* @ingroup SipPlatform
* @brief base64 문자열을 plain text 문자열로 변환한다.
* @param pszInput base64 문자열
* @param iInputLength base64 문자열 길이
* @param pszOutput plain text 를 저장할 변수
* @param iOutputLength plain text 를 저장할 변수의 크기
* @return 성공하면 변환된 문자열의 길이를 리턴하고 그렇지 않으면 -1 을 리턴한다.
*/
int Base64Decode( const char * pszInput, int iInputLength, char * pszOutput, int iOutputLength )
{
const unsigned char *pszCurrent = (const unsigned char *)pszInput;
unsigned char * pszResult = (unsigned char *)pszOutput;
int ch, i = 0, j = 0, k;
char *chp;
if( pszResult == NULL ) return -1;
if( iOutputLength < GetBase64DecodeLength(iInputLength) ) return -1;
while( (ch = *pszCurrent++) != '\0' )
{
if( ch == gcBase64Pad ) break;
chp = strchr(garrBase64Table, ch);
if (chp == NULL) continue;
ch = (int)(chp - garrBase64Table);
switch( i % 4 )
{
case 0:
pszResult[j] = ch << 2;
break;
case 1:
pszResult[j++] |= ch >> 4;
pszResult[j] = (ch & 0x0f) << 4;
break;
case 2:
pszResult[j++] |= ch >>2;
pszResult[j] = (ch & 0x03) << 6;
break;
case 3:
pszResult[j++] |= ch;
break;
}
i++;
}
k = j;
if( ch == gcBase64Pad )
{
switch(i % 4)
{
case 0:
case 1:
return -1;
case 2:
k++;
case 3:
pszResult[k++] = 0;
}
}
pszResult[k] = '\0';
return j;
}
/**
* @ingroup SipPlatform
* @brief plain text 를 base64 문자열로 변환한다.
* @param pszInput plain text 문자열
* @param iInputLength plain text 문자열의 길이
* @param strOutput base64 문자열 저장 변수
* @return 성공하면 true 를 리턴하고 실패하면 false 를 리턴한다.
*/
bool Base64Encode( const char * pszInput, int iInputLength, std::string & strOutput )
{
int iOutputLen = GetBase64EncodeLength( iInputLength );
char * pszOutput = (char *)malloc( iOutputLen );
if( pszOutput == NULL )
{
return false;
}
Base64Encode( pszInput, iInputLength, pszOutput, iOutputLen );
strOutput = pszOutput;
free( pszOutput );
return true;
}