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Andrew Francis base64 decode, my previous base64 encoder, new source …
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…header.

No BSD-style license.
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@bagder
bagder committed Aug 3, 2001
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355 changes: 231 additions & 124 deletions lib/base64.c
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@@ -1,34 +1,35 @@
/*
* Copyright (c) 1995 - 1999 Kungliga Tekniska Högskolan
* (Royal Institute of Technology, Stockholm, Sweden).
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. Neither the name of the Institute nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
/*****************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 2001, Andrew Francis and Daniel Stenberg
*
* In order to be useful for every potential user, curl and libcurl are
* dual-licensed under the MPL and the MIT/X-derivate licenses.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the MPL or the MIT/X-derivate
* licenses. You may pick one of these licenses.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* $Id$
*****************************************************************************/

/* Base64 encoding/decoding
*
* Test harnesses down the bottom - compile with -DTEST_ENCODE for
* a program that will read in raw data from stdin and write out
* a base64-encoded version to stdout, and the length returned by the
* encoding function to stderr. Compile with -DTEST_DECODE for a program that
* will go the other way.
*
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* This code will break if int is smaller than 32 bits
*/

#ifdef HAVE_CONFIG_H
Expand All @@ -38,115 +39,221 @@
#include <string.h>
#include "base64.h"

/* The last #include file should be: */
#ifdef MALLOCDEBUG
#include "memdebug.h"
#endif

static char base64[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";

static int pos(char c)
static void decodeQuantum(unsigned char *dest, char *src)
{
char *p;
for(p = base64; *p; p++)
if(*p == c)
return p - base64;
return -1;
unsigned int x = 0;
int i;
for(i = 0; i < 4; i++) {
if(src[i] >= 'A' && src[i] <= 'Z')
x = (x << 6) + (unsigned int)(src[i] - 'A' + 0);
else if(src[i] >= 'a' && src[i] <= 'z')
x = (x << 6) + (unsigned int)(src[i] - 'a' + 26);
else if(src[i] >= '0' && src[i] <= '9')
x = (x << 6) + (unsigned int)(src[i] - '0' + 52);
else if(src[i] == '+')
x = (x << 6) + 62;
else if(src[i] == '/')
x = (x << 6) + 63;
}

dest[2] = (unsigned char)(x & 255); x >>= 8;
dest[1] = (unsigned char)(x & 255); x >>= 8;
dest[0] = (unsigned char)(x & 255); x >>= 8;
}

#if 1
int Curl_base64_encode(const void *data, int size, char **str)
/* base64Decode
* Given a base64 string at src, decode it into the memory pointed
* to by dest. If rawLength points to a valid address (ie not NULL),
* store the length of the decoded data to it.
*/
static void base64Decode(unsigned char *dest, char *src, int *rawLength)
{
char *s, *p;
int length = 0;
int equalsTerm = 0;
int i;
int c;
const unsigned char *q;

p = s = (char*)malloc(size*4/3+4);
if (p == NULL)
return -1;
q = (const unsigned char*)data;
i=0;
for(i = 0; i < size;){
c=q[i++];
c*=256;
if(i < size)
c+=q[i];
i++;
c*=256;
if(i < size)
c+=q[i];
i++;
p[0]=base64[(c&0x00fc0000) >> 18];
p[1]=base64[(c&0x0003f000) >> 12];
p[2]=base64[(c&0x00000fc0) >> 6];
p[3]=base64[(c&0x0000003f) >> 0];
if(i > size)
p[3]='=';
if(i > size+1)
p[2]='=';
p+=4;
unsigned char lastQuantum[3];

while((src[length] != '=') && src[length])
length++;
while(src[length+equalsTerm] == '=')
equalsTerm++;

if(rawLength)
*rawLength = (length * 3 / 4) - equalsTerm;

for(i = 0; i < length/4 - 1; i++) {
decodeQuantum(dest, src);
dest += 3; src += 4;
}
*p=0;
*str = s;
return strlen(s);

decodeQuantum(lastQuantum, src);
for(i = 0; i < 3 - equalsTerm; i++) dest[i] = lastQuantum[i];

}
#endif

int Curl_base64_decode(const char *str, void *data)
/* ---- Base64 Encoding --- */
static char table64[]=
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";

/*
* Curl_base64_encode()
*
* Returns the length of the newly created base64 string. The third argument
* is a pointer to an allocated area holding the base64 data. If something
* went wrong, -1 is returned.
*
*/
int Curl_base64_encode(const void *inp, int insize, char **outptr)
{
const char *p;
unsigned char *q;
int c;
int x;
int done = 0;
q=(unsigned char*)data;
for(p=str; *p && !done; p+=4){
x = pos(p[0]);
if(x >= 0)
c = x;
else{
done = 3;
break;
}
c*=64;

x = pos(p[1]);
if(x >= 0)
c += x;
else
return -1;
c*=64;

if(p[2] == '=')
done++;
else{
x = pos(p[2]);
if(x >= 0)
c += x;
unsigned char ibuf[3];
unsigned char obuf[4];
int i;
int inputparts;
char *output;
char *base64data;

char *indata = (char *)inp;

if(0 == insize)
insize = strlen(indata);

base64data = output = (char*)malloc(insize*4/3+4);
if(NULL == output)
return -1;

while(insize > 0) {
for (i = inputparts = 0; i < 3; i++) {
if(*indata) {
inputparts++;
ibuf[i] = *indata;
indata++;
insize--;
}
else
return -1;
ibuf[i] = 0;
}
c*=64;

if(p[3] == '=')
done++;
else{
if(done)
return -1;
x = pos(p[3]);
if(x >= 0)
c += x;
else
return -1;

obuf [0] = (ibuf [0] & 0xFC) >> 2;
obuf [1] = ((ibuf [0] & 0x03) << 4) | ((ibuf [1] & 0xF0) >> 4);
obuf [2] = ((ibuf [1] & 0x0F) << 2) | ((ibuf [2] & 0xC0) >> 6);
obuf [3] = ibuf [2] & 0x3F;

switch(inputparts) {
case 1: /* only one byte read */
sprintf(output, "%c%c==",
table64[obuf[0]],
table64[obuf[1]]);
break;
case 2: /* two bytes read */
sprintf(output, "%c%c%c=",
table64[obuf[0]],
table64[obuf[1]],
table64[obuf[2]]);
break;
default:
sprintf(output, "%c%c%c%c",
table64[obuf[0]],
table64[obuf[1]],
table64[obuf[2]],
table64[obuf[3]] );
break;
}
if(done < 3)
*q++=(c&0x00ff0000)>>16;

if(done < 2)
*q++=(c&0x0000ff00)>>8;
if(done < 1)
*q++=(c&0x000000ff)>>0;
output += 4;
}
return q - (unsigned char*)data;
*output=0;
*outptr = base64data; /* make it return the actual data memory */

return strlen(base64data); /* return the length of the new data */
}
/* ---- End of Base64 Encoding ---- */

int Curl_base64_decode(const char *str, void *data)
{
int ret;

base64Decode((unsigned char *)data, (char *)str, &ret);
return ret;
}

/************* TEST HARNESS STUFF ****************/


#ifdef TEST_ENCODE
/* encoding test harness. Read in standard input and write out the length
* returned by Curl_base64_encode, followed by the base64'd data itself
*/
#include <stdio.h>

#define TEST_NEED_SUCK
void *suck(int *);

int main(int argc, char **argv, char **envp) {
char *base64;
int base64Len;
unsigned char *data;
int dataLen;

data = (unsigned char *)suck(&dataLen);
base64Len = Curl_base64_encode(data, dataLen, &base64);

fprintf(stderr, "%d\n", base64Len);
fprintf(stdout, "%s", base64);

free(base64); free(data);
return 0;
}
#endif

#ifdef TEST_DECODE
/* decoding test harness. Read in a base64 string from stdin and write out the
* length returned by Curl_base64_decode, followed by the decoded data itself
*/
#include <stdio.h>

#define TEST_NEED_SUCK
void *suck(int *);

int main(int argc, char **argv, char **envp) {
char *base64;
int base64Len;
unsigned char *data;
int dataLen;

base64 = (char *)suck(&base64Len);
data = (unsigned char *)malloc(base64Len * 3/4 + 8);
dataLen = Curl_base64_decode(base64, data);

fprintf(stderr, "%d\n", dataLen);
fwrite(data,1,dataLen,stdout);


free(base64); free(data);
return 0;
}
#endif

#ifdef TEST_NEED_SUCK
/* this function 'sucks' in as much as possible from stdin */
void *suck(int *lenptr) {
int cursize = 8192;
unsigned char *buf = NULL;
int lastread;
int len = 0;

do {
cursize *= 2;
buf = (unsigned char *)realloc(buf, cursize);
memset(buf + len, 0, cursize - len);
lastread = fread(buf + len, 1, cursize - len, stdin);
len += lastread;
} while(!feof(stdin));

lenptr[0] = len;
return (void *)buf;
}
#endif

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