/* | |
* RFC 1521 base64 encoding/decoding | |
* | |
* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved | |
* SPDX-License-Identifier: Apache-2.0 | |
* | |
* Licensed under the Apache License, Version 2.0 (the "License"); you may | |
* not use this file except in compliance with the License. | |
* You may obtain a copy of the License at | |
* | |
* http://www.apache.org/licenses/LICENSE-2.0 | |
* | |
* Unless required by applicable law or agreed to in writing, software | |
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT | |
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
* See the License for the specific language governing permissions and | |
* limitations under the License. | |
* | |
* 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 */ |