#include "curl_setup.h"
#include "urldata.h"
#include "warnless.h"
#include "curl_base64.h"
#include "non-ascii.h"
#include "curl_printf.h"
#include "curl_memory.h"
#include "memdebug.h"
static const char base64[]=
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
static const char base64url[]=
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_";
static size_t decodeQuantum(unsigned char *dest, const char *src)
{
size_t padding = 0;
const char *s, *p;
unsigned long i, x = 0;
for(i = 0, s = src; i < 4; i++, s++) {
if(*s == '=') {
x = (x << 6);
padding++;
}
else {
unsigned long v = 0;
p = base64;
while(*p && (*p != *s)) {
v++;
p++;
}
if(*p == *s)
x = (x << 6) + v;
else
return 0;
}
}
if(padding < 1)
dest[2] = curlx_ultouc(x & 0xFFUL);
x >>= 8;
if(padding < 2)
dest[1] = curlx_ultouc(x & 0xFFUL);
x >>= 8;
dest[0] = curlx_ultouc(x & 0xFFUL);
return 3 - padding;
}
CURLcode Curl_base64_decode(const char *src,
unsigned char **outptr, size_t *outlen)
{
size_t srclen = 0;
size_t length = 0;
size_t padding = 0;
size_t i;
size_t numQuantums;
size_t rawlen = 0;
unsigned char *pos;
unsigned char *newstr;
*outptr = NULL;
*outlen = 0;
srclen = strlen(src);
if(!srclen || srclen % 4)
return CURLE_BAD_CONTENT_ENCODING;
while((src[length] != '=') && src[length])
length++;
if(src[length] == '=') {
padding++;
if(src[length + 1] == '=')
padding++;
}
if(length + padding != srclen)
return CURLE_BAD_CONTENT_ENCODING;
numQuantums = srclen / 4;
rawlen = (numQuantums * 3) - padding;
newstr = malloc(rawlen + 1);
if(!newstr)
return CURLE_OUT_OF_MEMORY;
pos = newstr;
for(i = 0; i < numQuantums; i++) {
size_t result = decodeQuantum(pos, src);
if(!result) {
free(newstr);
return CURLE_BAD_CONTENT_ENCODING;
}
pos += result;
src += 4;
}
*pos = '\0';
*outptr = newstr;
*outlen = rawlen;
return CURLE_OK;
}
static CURLcode base64_encode(const char *table64,
struct Curl_easy *data,
const char *inputbuff, size_t insize,
char **outptr, size_t *outlen)
{
CURLcode result;
unsigned char ibuf[3];
unsigned char obuf[4];
int i;
int inputparts;
char *output;
char *base64data;
char *convbuf = NULL;
const char *indata = inputbuff;
*outptr = NULL;
*outlen = 0;
if(!insize)
insize = strlen(indata);
#if SIZEOF_SIZE_T == 4
if(insize > UINT_MAX/4)
return CURLE_OUT_OF_MEMORY;
#endif
base64data = output = malloc(insize * 4 / 3 + 4);
if(!output)
return CURLE_OUT_OF_MEMORY;
result = Curl_convert_clone(data, indata, insize, &convbuf);
if(result) {
free(output);
return result;
}
if(convbuf)
indata = (char *)convbuf;
while(insize > 0) {
for(i = inputparts = 0; i < 3; i++) {
if(insize > 0) {
inputparts++;
ibuf[i] = (unsigned char) *indata;
indata++;
insize--;
}
else
ibuf[i] = 0;
}
obuf[0] = (unsigned char) ((ibuf[0] & 0xFC) >> 2);
obuf[1] = (unsigned char) (((ibuf[0] & 0x03) << 4) | \
((ibuf[1] & 0xF0) >> 4));
obuf[2] = (unsigned char) (((ibuf[1] & 0x0F) << 2) | \
((ibuf[2] & 0xC0) >> 6));
obuf[3] = (unsigned char) (ibuf[2] & 0x3F);
switch(inputparts) {
case 1:
msnprintf(output, 5, "%c%c==",
table64[obuf[0]],
table64[obuf[1]]);
break;
case 2:
msnprintf(output, 5, "%c%c%c=",
table64[obuf[0]],
table64[obuf[1]],
table64[obuf[2]]);
break;
default:
msnprintf(output, 5, "%c%c%c%c",
table64[obuf[0]],
table64[obuf[1]],
table64[obuf[2]],
table64[obuf[3]]);
break;
}
output += 4;
}
*output = '\0';
*outptr = base64data;
free(convbuf);
*outlen = strlen(base64data);
return CURLE_OK;
}
CURLcode Curl_base64_encode(struct Curl_easy *data,
const char *inputbuff, size_t insize,
char **outptr, size_t *outlen)
{
return base64_encode(base64, data, inputbuff, insize, outptr, outlen);
}
CURLcode Curl_base64url_encode(struct Curl_easy *data,
const char *inputbuff, size_t insize,
char **outptr, size_t *outlen)
{
return base64_encode(base64url, data, inputbuff, insize, outptr, outlen);
}