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/*
* Embedded Linux library
* Copyright (C) 2015 Intel Corporation
*
* SPDX-License-Identifier: LGPL-2.1-or-later
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdint.h>
#include "utf8.h"
#include "base64.h"
#include "private.h"
#include "useful.h"
#include <stdio.h>
LIB_EXPORT uint8_t *l_base64_decode(const char *in, size_t in_len,
size_t *n_written)
{
const char *ptr, *in_end = in + in_len;
const char *base64_end = NULL;
uint8_t *out_buf, *out;
int base64_len = 0, pad_len = 0;
uint16_t reg = 0;
for (ptr = in; ptr < in_end; ptr++) {
if (l_ascii_isspace(*ptr))
/* Whitespace */
continue;
else if (*ptr == '=') {
/* Final padding */
if (!pad_len)
base64_end = ptr;
pad_len++;
} else if (!pad_len && (l_ascii_isalnum(*ptr) || *ptr == '+' ||
*ptr == '/'))
/* Base64 character */
base64_len++;
else
/* Bad character */
return NULL;
}
if (ptr != in_end)
return NULL;
if ((base64_len & 3) == 1)
/* Invalid length */
return NULL;
if (pad_len != align_len(base64_len, 4) - base64_len)
return NULL;
/* No padding */
if (!base64_end)
base64_end = ptr;
*n_written = base64_len * 3 / 4;
out_buf = l_malloc(*n_written);
out = out_buf;
base64_len = 0;
for (ptr = in; ptr < base64_end; ptr++) {
if (l_ascii_isspace(*ptr))
/* Whitespace */
continue;
/* Base64 character */
reg <<= 6;
if (l_ascii_isupper(*ptr))
reg |= *ptr - 'A' + 0;
else if (l_ascii_islower(*ptr))
reg |= *ptr - 'a' + 26;
else if (l_ascii_isdigit(*ptr))
reg |= *ptr - '0' + 52;
else if (*ptr == '+')
reg |= 62;
else if (*ptr == '/')
reg |= 63;
if ((base64_len & 3) == 1)
*out++ = reg >> 4;
else if ((base64_len & 3) == 2)
*out++ = reg >> 2;
else if ((base64_len & 3) == 3)
*out++ = reg >> 0;
base64_len++;
}
return out_buf;
}
LIB_EXPORT char *l_base64_encode(const uint8_t *in, size_t in_len, int columns)
{
const uint8_t *in_end = in + in_len;
char *out_buf, *out;
size_t out_len;
uint32_t reg;
uint8_t idx;
int i, pad = 4;
int col = 0;
/* For simplicity allow multiples of 4 only */
if (columns & 3)
return NULL;
out_len = (in_len + 2) / 3 * 4;
if (columns && out_len)
out_len += (out_len - 4) / columns;
out_buf = l_malloc(out_len + 1);
out = out_buf;
while (in < in_end) {
reg = *in++ << 16;
if (in < in_end)
reg |= *in++ << 8;
else
pad--;
if (in < in_end)
reg |= *in++ << 0;
else
pad--;
if (columns && col == columns) {
*out++ = '\n';
col = 0;
}
col += 4;
for (i = 0; i < pad; i++) {
idx = (reg >> 18) & 63;
reg <<= 6;
if (idx < 26)
*out++ = idx + 'A';
else if (idx < 52)
*out++ = idx - 26 + 'a';
else if (idx < 62)
*out++ = idx - 52 + '0';
else
*out++ = (idx == 62) ? '+' : '/';
}
}
for (; pad < 4; pad++)
*out++ = '=';
*out = '\0';
return out_buf;
}
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