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/* ... */
#include "includes.h"
#include <stdint.h>
#include "os.h"
#include "base64.h"
static const char base64_table[65] =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
static const char base64_url_table[65] =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_";
static char * base64_gen_encode(const unsigned char *src, size_t len,
size_t *out_len, const char *table, int add_pad)
{
char *out, *pos;
const unsigned char *end, *in;
size_t olen;
int line_len;
if (len >= SIZE_MAX / 4)
return NULL;
olen = len * 4 / 3 + 4;
if (add_pad)
olen += olen / 72;
olen++;
if (olen < len)
return NULL;
out = os_malloc(olen);
if (out == NULL)
return NULL;
end = src + len;
in = src;
pos = out;
line_len = 0;
while (end - in >= 3) {
*pos++ = table[(in[0] >> 2) & 0x3f];
*pos++ = table[(((in[0] & 0x03) << 4) | (in[1] >> 4)) & 0x3f];
*pos++ = table[(((in[1] & 0x0f) << 2) | (in[2] >> 6)) & 0x3f];
*pos++ = table[in[2] & 0x3f];
in += 3;
line_len += 4;
if (add_pad && line_len >= 72) {
*pos++ = '\n';
line_len = 0;
}{...}
}{...}
if (end - in) {
*pos++ = table[(in[0] >> 2) & 0x3f];
if (end - in == 1) {
*pos++ = table[((in[0] & 0x03) << 4) & 0x3f];
if (add_pad)
*pos++ = '=';
}{...} else {
*pos++ = table[(((in[0] & 0x03) << 4) |
(in[1] >> 4)) & 0x3f];
*pos++ = table[((in[1] & 0x0f) << 2) & 0x3f];
}{...}
if (add_pad)
*pos++ = '=';
line_len += 4;
}{...}
if (add_pad && line_len)
*pos++ = '\n';
*pos = '\0';
if (out_len)
*out_len = pos - out;
return out;
}{ ... }
static unsigned char * base64_gen_decode(const char *src, size_t len,
size_t *out_len, const char *table)
{
unsigned char dtable[256], *out, *pos, block[4], tmp;
size_t i, count, olen;
int pad = 0;
size_t extra_pad;
os_memset(dtable, 0x80, 256);
for (i = 0; i < sizeof(base64_table) - 1; i++)
dtable[(unsigned char) table[i]] = (unsigned char) i;
dtable['='] = 0;
count = 0;
for (i = 0; i < len; i++) {
if (dtable[(unsigned char) src[i]] != 0x80)
count++;
}{...}
if (count == 0)
return NULL;
extra_pad = (4 - count % 4) % 4;
olen = (count + extra_pad) / 4 * 3;
pos = out = os_malloc(olen);
if (out == NULL)
return NULL;
count = 0;
for (i = 0; i < len + extra_pad; i++) {
unsigned char val;
if (i >= len)
val = '=';
else
val = src[i];
tmp = dtable[val];
if (tmp == 0x80)
continue;
if (val == '=')
pad++;
block[count] = tmp;
count++;
if (count == 4) {
*pos++ = (block[0] << 2) | (block[1] >> 4);
*pos++ = (block[1] << 4) | (block[2] >> 2);
*pos++ = (block[2] << 6) | block[3];
count = 0;
if (pad) {
if (pad == 1)
pos--;
else if (pad == 2)
pos -= 2;
else {
os_free(out);
return NULL;
}{...}
break;
}{...}
}{...}
}{...}
*out_len = pos - out;
return out;
}{ ... }
/* ... */
char * base64_encode(const void *src, size_t len, size_t *out_len)
{
return base64_gen_encode(src, len, out_len, base64_table, 1);
}{ ... }
char * base64_url_encode(const void *src, size_t len, size_t *out_len)
{
return base64_gen_encode(src, len, out_len, base64_url_table, 0);
}{ ... }
/* ... */
unsigned char * base64_decode(const char *src, size_t len, size_t *out_len)
{
return base64_gen_decode(src, len, out_len, base64_table);
}{ ... }
unsigned char * base64_url_decode(const char *src, size_t len, size_t *out_len)
{
return base64_gen_decode(src, len, out_len, base64_url_table);
}{ ... }