diff options
Diffstat (limited to 'thirdparty/mbedtls/library/base64.c')
| -rw-r--r-- | thirdparty/mbedtls/library/base64.c | 250 |
1 files changed, 50 insertions, 200 deletions
diff --git a/thirdparty/mbedtls/library/base64.c b/thirdparty/mbedtls/library/base64.c index 692e11e3fa..83daa0bcc6 100644 --- a/thirdparty/mbedtls/library/base64.c +++ b/thirdparty/mbedtls/library/base64.c @@ -2,13 +2,7 @@ * RFC 1521 base64 encoding/decoding * * Copyright The Mbed TLS Contributors - * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later - * - * This file is provided under the Apache License 2.0, or the - * GNU General Public License v2.0 or later. - * - * ********** - * Apache License 2.0: + * 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. @@ -21,38 +15,14 @@ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. - * - * ********** - * - * ********** - * GNU General Public License v2.0 or later: - * - * 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. - * - * ********** */ -#if !defined(MBEDTLS_CONFIG_FILE) -#include "mbedtls/config.h" -#else -#include MBEDTLS_CONFIG_FILE -#endif +#include "common.h" #if defined(MBEDTLS_BASE64_C) #include "mbedtls/base64.h" +#include "constant_time_internal.h" #include <stdint.h> @@ -66,130 +36,9 @@ #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 */ /* - * Constant flow conditional assignment to unsigned char - */ -static void mbedtls_base64_cond_assign_uchar( unsigned char * dest, const unsigned char * const src, - unsigned char condition ) -{ - /* MSVC has a warning about unary minus on unsigned integer types, - * but this is well-defined and precisely what we want to do here. */ -#if defined(_MSC_VER) -#pragma warning( push ) -#pragma warning( disable : 4146 ) -#endif - - /* Generate bitmask from condition, mask will either be 0xFF or 0 */ - unsigned char mask = ( condition | -condition ); - mask >>= 7; - mask = -mask; - -#if defined(_MSC_VER) -#pragma warning( pop ) -#endif - - *dest = ( ( *src ) & mask ) | ( ( *dest ) & ~mask ); -} - -/* - * Constant flow conditional assignment to uint_32 - */ -static void mbedtls_base64_cond_assign_uint32( uint32_t * dest, const uint32_t src, - uint32_t condition ) -{ - /* MSVC has a warning about unary minus on unsigned integer types, - * but this is well-defined and precisely what we want to do here. */ -#if defined(_MSC_VER) -#pragma warning( push ) -#pragma warning( disable : 4146 ) -#endif - - /* Generate bitmask from condition, mask will either be 0xFFFFFFFF or 0 */ - uint32_t mask = ( condition | -condition ); - mask >>= 31; - mask = -mask; - -#if defined(_MSC_VER) -#pragma warning( pop ) -#endif - - *dest = ( src & mask ) | ( ( *dest ) & ~mask ); -} - -/* - * Constant flow check for equality - */ -static unsigned char mbedtls_base64_eq( size_t in_a, size_t in_b ) -{ - size_t difference = in_a ^ in_b; - - /* MSVC has a warning about unary minus on unsigned integer types, - * but this is well-defined and precisely what we want to do here. */ -#if defined(_MSC_VER) -#pragma warning( push ) -#pragma warning( disable : 4146 ) -#endif - - difference |= -difference; - -#if defined(_MSC_VER) -#pragma warning( pop ) -#endif - - /* cope with the varying size of size_t per platform */ - difference >>= ( sizeof( difference ) * 8 - 1 ); - - return (unsigned char) ( 1 ^ difference ); -} - -/* - * Constant flow lookup into table. - */ -static unsigned char mbedtls_base64_table_lookup( const unsigned char * const table, - const size_t table_size, const size_t table_index ) -{ - size_t i; - unsigned char result = 0; - - for( i = 0; i < table_size; ++i ) - { - mbedtls_base64_cond_assign_uchar( &result, &table[i], mbedtls_base64_eq( i, table_index ) ); - } - - return result; -} - -/* * Encode a buffer into base64 format */ int mbedtls_base64_encode( unsigned char *dst, size_t dlen, size_t *olen, @@ -229,17 +78,12 @@ int mbedtls_base64_encode( unsigned char *dst, size_t dlen, size_t *olen, C2 = *src++; C3 = *src++; - *p++ = mbedtls_base64_table_lookup( base64_enc_map, sizeof( base64_enc_map ), - ( ( C1 >> 2 ) & 0x3F ) ); - - *p++ = mbedtls_base64_table_lookup( base64_enc_map, sizeof( base64_enc_map ), - ( ( ( ( C1 & 3 ) << 4 ) + ( C2 >> 4 ) ) & 0x3F ) ); - - *p++ = mbedtls_base64_table_lookup( base64_enc_map, sizeof( base64_enc_map ), - ( ( ( ( C2 & 15 ) << 2 ) + ( C3 >> 6 ) ) & 0x3F ) ); - - *p++ = mbedtls_base64_table_lookup( base64_enc_map, sizeof( base64_enc_map ), - ( C3 & 0x3F ) ); + *p++ = mbedtls_ct_base64_enc_char( ( C1 >> 2 ) & 0x3F ); + *p++ = mbedtls_ct_base64_enc_char( ( ( ( C1 & 3 ) << 4 ) + ( C2 >> 4 ) ) + & 0x3F ); + *p++ = mbedtls_ct_base64_enc_char( ( ( ( C2 & 15 ) << 2 ) + ( C3 >> 6 ) ) + & 0x3F ); + *p++ = mbedtls_ct_base64_enc_char( C3 & 0x3F ); } if( i < slen ) @@ -247,15 +91,12 @@ int mbedtls_base64_encode( unsigned char *dst, size_t dlen, size_t *olen, C1 = *src++; C2 = ( ( i + 1 ) < slen ) ? *src++ : 0; - *p++ = mbedtls_base64_table_lookup( base64_enc_map, sizeof( base64_enc_map ), - ( ( C1 >> 2 ) & 0x3F ) ); - - *p++ = mbedtls_base64_table_lookup( base64_enc_map, sizeof( base64_enc_map ), - ( ( ( ( C1 & 3 ) << 4 ) + ( C2 >> 4 ) ) & 0x3F ) ); + *p++ = mbedtls_ct_base64_enc_char( ( C1 >> 2 ) & 0x3F ); + *p++ = mbedtls_ct_base64_enc_char( ( ( ( C1 & 3 ) << 4 ) + ( C2 >> 4 ) ) + & 0x3F ); if( ( i + 1 ) < slen ) - *p++ = mbedtls_base64_table_lookup( base64_enc_map, sizeof( base64_enc_map ), - ( ( ( C2 & 15 ) << 2 ) & 0x3F ) ); + *p++ = mbedtls_ct_base64_enc_char( ( ( C2 & 15 ) << 2 ) & 0x3F ); else *p++ = '='; *p++ = '='; @@ -273,20 +114,23 @@ int mbedtls_base64_encode( unsigned char *dst, size_t dlen, size_t *olen, 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; + size_t i; /* index in source */ + size_t n; /* number of digits or trailing = in source */ + uint32_t x; /* value accumulator */ + unsigned accumulated_digits = 0; + unsigned equals = 0; + int spaces_present = 0; unsigned char *p; - unsigned char dec_map_lookup; /* First pass: check for validity and get output length */ - for( i = n = j = 0; i < slen; i++ ) + for( i = n = 0; i < slen; i++ ) { /* Skip spaces before checking for EOL */ - x = 0; + spaces_present = 0; while( i < slen && src[i] == ' ' ) { ++i; - ++x; + spaces_present = 1; } /* Spaces at end of buffer are OK */ @@ -301,20 +145,24 @@ int mbedtls_base64_decode( unsigned char *dst, size_t dlen, size_t *olen, continue; /* Space inside a line is an error */ - if( x != 0 ) + if( spaces_present ) return( MBEDTLS_ERR_BASE64_INVALID_CHARACTER ); - if( src[i] == '=' && ++j > 2 ) - return( MBEDTLS_ERR_BASE64_INVALID_CHARACTER ); - - dec_map_lookup = mbedtls_base64_table_lookup( base64_dec_map, sizeof( base64_dec_map ), src[i] ); - - if( src[i] > 127 || dec_map_lookup == 127 ) - return( MBEDTLS_ERR_BASE64_INVALID_CHARACTER ); - - if( dec_map_lookup < 64 && j != 0 ) + if( src[i] > 127 ) return( MBEDTLS_ERR_BASE64_INVALID_CHARACTER ); + if( src[i] == '=' ) + { + if( ++equals > 2 ) + return( MBEDTLS_ERR_BASE64_INVALID_CHARACTER ); + } + else + { + if( equals != 0 ) + return( MBEDTLS_ERR_BASE64_INVALID_CHARACTER ); + if( mbedtls_ct_base64_dec_value( src[i] ) < 0 ) + return( MBEDTLS_ERR_BASE64_INVALID_CHARACTER ); + } n++; } @@ -329,7 +177,7 @@ int mbedtls_base64_decode( unsigned char *dst, size_t dlen, size_t *olen, * n = ( ( n * 6 ) + 7 ) >> 3; */ n = ( 6 * ( n >> 3 ) ) + ( ( 6 * ( n & 0x7 ) + 7 ) >> 3 ); - n -= j; + n -= equals; if( dst == NULL || dlen < n ) { @@ -337,22 +185,24 @@ int mbedtls_base64_decode( unsigned char *dst, size_t dlen, size_t *olen, return( MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL ); } - for( j = 3, n = x = 0, p = dst; i > 0; i--, src++ ) - { + equals = 0; + for( x = 0, p = dst; i > 0; i--, src++ ) + { if( *src == '\r' || *src == '\n' || *src == ' ' ) continue; - dec_map_lookup = mbedtls_base64_table_lookup( base64_dec_map, sizeof( base64_dec_map ), *src ); - - mbedtls_base64_cond_assign_uint32( &j, j - 1, mbedtls_base64_eq( dec_map_lookup, 64 ) ); - x = ( x << 6 ) | ( dec_map_lookup & 0x3F ); + x = x << 6; + if( *src == '=' ) + ++equals; + else + x |= mbedtls_ct_base64_dec_value( *src ); - if( ++n == 4 ) + if( ++accumulated_digits == 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 ); + accumulated_digits = 0; + *p++ = MBEDTLS_BYTE_2( x ); + if( equals <= 1 ) *p++ = MBEDTLS_BYTE_1( x ); + if( equals <= 0 ) *p++ = MBEDTLS_BYTE_0( x ); } } |