/*
* RFC 1521 base64 encoding/decoding
*
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
* SPDX-License-Identifier: GPL-2.0
*
* 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 2 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* This file is part of mbed TLS (https://tls.mbed.org)
*/
#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#if defined(MBEDTLS_BASE64_C)
#include "mbedtls/base64.h"
#include <stdint.h>
#if defined(MBEDTLS_SELF_TEST)
#include <string.h>
#if defined(MBEDTLS_PLATFORM_C)
#include "mbedtls/platform.h"
#else
#include <stdio.h>
#define mbedtls_printf printf
#endif /* MBEDTLS_PLATFORM_C */
#endif /* MBEDTLS_SELF_TEST */
static const unsigned char base64_enc_map[64] = {
'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', '+', '/'
};
static const unsigned char base64_dec_map[128] = {
127, 127, 127, 127, 127, 127, 127, 127, 127, 127,
127, 127, 127, 127, 127, 127, 127, 127, 127, 127,
127, 127, 127, 127, 127, 127, 127, 127, 127, 127,
127, 127, 127, 127, 127, 127, 127, 127, 127, 127,
127, 127, 127, 62, 127, 127, 127, 63, 52, 53,
54, 55, 56, 57, 58, 59, 60, 61, 127, 127,
127, 64, 127, 127, 127, 0, 1, 2, 3, 4,
5, 6, 7, 8, 9, 10, 11, 12, 13, 14,
15, 16, 17, 18, 19, 20, 21, 22, 23, 24,
25, 127, 127, 127, 127, 127, 127, 26, 27, 28,
29, 30, 31, 32, 33, 34, 35, 36, 37, 38,
39, 40, 41, 42, 43, 44, 45, 46, 47, 48,
49, 50, 51, 127, 127, 127, 127, 127
};
#define BASE64_SIZE_T_MAX ( (size_t) -1 ) /* SIZE_T_MAX is not standard */
/*
* Encode a buffer into base64 format
*/
int mbedtls_base64_encode(unsigned char *dst, size_t dlen, size_t *olen,
const unsigned char *src, size_t slen) {
size_t i, n;
int C1, C2, C3;
unsigned char *p;
if (slen == 0) {
*olen = 0;
return (0);
}
n = slen / 3 + (slen % 3 != 0);
if (n > (BASE64_SIZE_T_MAX - 1) / 4) {
*olen = BASE64_SIZE_T_MAX;
return (MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL);
}
n *= 4;
if ((dlen < n + 1) || (NULL == dst)) {
*olen = n + 1;
return (MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL);
}
n = (slen / 3) * 3;
for (i = 0, p = dst; i < n; i += 3) {
C1 = *src++;
C2 = *src++;
C3 = *src++;
*p++ = base64_enc_map[(C1 >> 2) & 0x3F];
*p++ = base64_enc_map[(((C1 & 3) << 4) + (C2 >> 4)) & 0x3F];
*p++ = base64_enc_map[(((C2 & 15) << 2) + (C3 >> 6)) & 0x3F];
*p++ = base64_enc_map[C3 & 0x3F];
}
if (i < slen) {
C1 = *src++;
C2 = ((i + 1) < slen) ? *src++ : 0;
*p++ = base64_enc_map[(C1 >> 2) & 0x3F];
*p++ = base64_enc_map[(((C1 & 3) << 4) + (C2 >> 4)) & 0x3F];
if ((i + 1) < slen)
*p++ = base64_enc_map[((C2 & 15) << 2) & 0x3F];
else *p++ = '=';
*p++ = '=';
}
*olen = p - dst;
*p = 0;
return (0);
}
/*
* Decode a base64-formatted buffer
*/
int mbedtls_base64_decode(unsigned char *dst, size_t dlen, size_t *olen,
const unsigned char *src, size_t slen) {
size_t i, n;
uint32_t j, x;
unsigned char *p;
/* First pass: check for validity and get output length */
for (i = n = j = 0; i < slen; i++) {
/* Skip spaces before checking for EOL */
x = 0;
while (i < slen && src[i] == ' ') {
++i;
++x;
}
/* Spaces at end of buffer are OK */
if (i == slen)
break;
if ((slen - i) >= 2 &&
src[i] == '\r' && src[i + 1] == '\n')
continue;
if (src[i] == '\n')
continue;
/* Space inside a line is an error */
if (x != 0)
return (MBEDTLS_ERR_BASE64_INVALID_CHARACTER);
if (src[i] == '=' && ++j > 2)
return (MBEDTLS_ERR_BASE64_INVALID_CHARACTER);
if (src[i] > 127 || base64_dec_map[src[i]] == 127)
return (MBEDTLS_ERR_BASE64_INVALID_CHARACTER);
if (base64_dec_map[src[i]] < 64 && j != 0)
return (MBEDTLS_ERR_BASE64_INVALID_CHARACTER);
n++;
}
if (n == 0) {
*olen = 0;
return (0);
}
/* The following expression is to calculate the following formula without
* risk of integer overflow in n:
* n = ( ( n * 6 ) + 7 ) >> 3;
*/
n = (6 * (n >> 3)) + ((6 * (n & 0x7) + 7) >> 3);
n -= j;
if (dst == NULL || dlen < n) {
*olen = n;
return (MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL);
}
for (j = 3, n = x = 0, p = dst; i > 0; i--, src++) {
if (*src == '\r' || *src == '\n' || *src == ' ')
continue;
j -= (base64_dec_map[*src] == 64);
x = (x << 6) | (base64_dec_map[*src] & 0x3F);
if (++n == 4) {
n = 0;
if (j > 0) *p++ = (unsigned char)(x >> 16);
if (j > 1) *p++ = (unsigned char)(x >> 8);
if (j > 2) *p++ = (unsigned char)(x);
}
}
*olen = p - dst;
return (0);
}
#if defined(MBEDTLS_SELF_TEST)
static const unsigned char base64_test_dec[64] = {
0x24, 0x48, 0x6E, 0x56, 0x87, 0x62, 0x5A, 0xBD,
0xBF, 0x17, 0xD9, 0xA2, 0xC4, 0x17, 0x1A, 0x01,
0x94, 0xED, 0x8F, 0x1E, 0x11, 0xB3, 0xD7, 0x09,
0x0C, 0xB6, 0xE9, 0x10, 0x6F, 0x22, 0xEE, 0x13,
0xCA, 0xB3, 0x07, 0x05, 0x76, 0xC9, 0xFA, 0x31,
0x6C, 0x08, 0x34, 0xFF, 0x8D, 0xC2, 0x6C, 0x38,
0x00, 0x43, 0xE9, 0x54, 0x97, 0xAF, 0x50, 0x4B,
0xD1, 0x41, 0xBA, 0x95, 0x31, 0x5A, 0x0B, 0x97
};
static const unsigned char base64_test_enc[] =
"JEhuVodiWr2/F9mixBcaAZTtjx4Rs9cJDLbpEG8i7hPK"
"swcFdsn6MWwINP+Nwmw4AEPpVJevUEvRQbqVMVoLlw==";
/*
* Checkup routine
*/
int mbedtls_base64_self_test(int verbose) {
size_t len;
const unsigned char *src;
unsigned char buffer[128];
if (verbose != 0)
mbedtls_printf(" Base64 encoding test: ");
src = base64_test_dec;
if (mbedtls_base64_encode(buffer, sizeof(buffer), &len, src, 64) != 0 ||
memcmp(base64_test_enc, buffer, 88) != 0) {
if (verbose != 0)
mbedtls_printf("failed\n");
return (1);
}
if (verbose != 0)
mbedtls_printf("passed\n Base64 decoding test: ");
src = base64_test_enc;
if (mbedtls_base64_decode(buffer, sizeof(buffer), &len, src, 88) != 0 ||
memcmp(base64_test_dec, buffer, 64) != 0) {
if (verbose != 0)
mbedtls_printf("failed\n");
return (1);
}
if (verbose != 0)
mbedtls_printf("passed\n\n");
return (0);
}
#endif /* MBEDTLS_SELF_TEST */
#endif /* MBEDTLS_BASE64_C */