diff options
Diffstat (limited to 'thirdparty/mbedtls/library/base64.c')
| -rw-r--r-- | thirdparty/mbedtls/library/base64.c | 123 |
1 files changed, 18 insertions, 105 deletions
diff --git a/thirdparty/mbedtls/library/base64.c b/thirdparty/mbedtls/library/base64.c index b89313062b..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> @@ -68,38 +38,6 @@ #define BASE64_SIZE_T_MAX ( (size_t) -1 ) /* SIZE_T_MAX is not standard */ -/* Return 0xff if low <= c <= high, 0 otherwise. - * - * Constant flow with respect to c. - */ -static unsigned char mask_of_range( unsigned char low, unsigned char high, - unsigned char c ) -{ - /* low_mask is: 0 if low <= c, 0x...ff if low > c */ - unsigned low_mask = ( (unsigned) c - low ) >> 8; - /* high_mask is: 0 if c <= high, 0x...ff if high > c */ - unsigned high_mask = ( (unsigned) high - c ) >> 8; - return( ~( low_mask | high_mask ) & 0xff ); -} - -/* Given a value in the range 0..63, return the corresponding Base64 digit. - * The implementation assumes that letters are consecutive (e.g. ASCII - * but not EBCDIC). - */ -static unsigned char enc_char( unsigned char val ) -{ - unsigned char digit = 0; - /* For each range of values, if val is in that range, mask digit with - * the corresponding value. Since val can only be in a single range, - * only at most one masking will change digit. */ - digit |= mask_of_range( 0, 25, val ) & ( 'A' + val ); - digit |= mask_of_range( 26, 51, val ) & ( 'a' + val - 26 ); - digit |= mask_of_range( 52, 61, val ) & ( '0' + val - 52 ); - digit |= mask_of_range( 62, 62, val ) & '+'; - digit |= mask_of_range( 63, 63, val ) & '/'; - return( digit ); -} - /* * Encode a buffer into base64 format */ @@ -140,10 +78,12 @@ int mbedtls_base64_encode( unsigned char *dst, size_t dlen, size_t *olen, C2 = *src++; C3 = *src++; - *p++ = enc_char( ( C1 >> 2 ) & 0x3F ); - *p++ = enc_char( ( ( ( C1 & 3 ) << 4 ) + ( C2 >> 4 ) ) & 0x3F ); - *p++ = enc_char( ( ( ( C2 & 15 ) << 2 ) + ( C3 >> 6 ) ) & 0x3F ); - *p++ = enc_char( 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 ) @@ -151,11 +91,12 @@ int mbedtls_base64_encode( unsigned char *dst, size_t dlen, size_t *olen, C1 = *src++; C2 = ( ( i + 1 ) < slen ) ? *src++ : 0; - *p++ = enc_char( ( C1 >> 2 ) & 0x3F ); - *p++ = enc_char( ( ( ( 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++ = enc_char( ( ( C2 & 15 ) << 2 ) & 0x3F ); + *p++ = mbedtls_ct_base64_enc_char( ( ( C2 & 15 ) << 2 ) & 0x3F ); else *p++ = '='; *p++ = '='; @@ -167,34 +108,6 @@ int mbedtls_base64_encode( unsigned char *dst, size_t dlen, size_t *olen, return( 0 ); } -/* Given a Base64 digit, return its value. - * If c is not a Base64 digit ('A'..'Z', 'a'..'z', '0'..'9', '+' or '/'), - * return -1. - * - * The implementation assumes that letters are consecutive (e.g. ASCII - * but not EBCDIC). - * - * The implementation is constant-flow (no branch or memory access depending - * on the value of c) unless the compiler inlines and optimizes a specific - * access. - */ -static signed char dec_value( unsigned char c ) -{ - unsigned char val = 0; - /* For each range of digits, if c is in that range, mask val with - * the corresponding value. Since c can only be in a single range, - * only at most one masking will change val. Set val to one plus - * the desired value so that it stays 0 if c is in none of the ranges. */ - val |= mask_of_range( 'A', 'Z', c ) & ( c - 'A' + 0 + 1 ); - val |= mask_of_range( 'a', 'z', c ) & ( c - 'a' + 26 + 1 ); - val |= mask_of_range( '0', '9', c ) & ( c - '0' + 52 + 1 ); - val |= mask_of_range( '+', '+', c ) & ( c - '+' + 62 + 1 ); - val |= mask_of_range( '/', '/', c ) & ( c - '/' + 63 + 1 ); - /* At this point, val is 0 if c is an invalid digit and v+1 if c is - * a digit with the value v. */ - return( val - 1 ); -} - /* * Decode a base64-formatted buffer */ @@ -247,7 +160,7 @@ int mbedtls_base64_decode( unsigned char *dst, size_t dlen, size_t *olen, { if( equals != 0 ) return( MBEDTLS_ERR_BASE64_INVALID_CHARACTER ); - if( dec_value( src[i] ) < 0 ) + if( mbedtls_ct_base64_dec_value( src[i] ) < 0 ) return( MBEDTLS_ERR_BASE64_INVALID_CHARACTER ); } n++; @@ -282,14 +195,14 @@ int mbedtls_base64_decode( unsigned char *dst, size_t dlen, size_t *olen, if( *src == '=' ) ++equals; else - x |= dec_value( *src ); + x |= mbedtls_ct_base64_dec_value( *src ); if( ++accumulated_digits == 4 ) { accumulated_digits = 0; - *p++ = (unsigned char)( x >> 16 ); - if( equals <= 1 ) *p++ = (unsigned char)( x >> 8 ); - if( equals <= 0 ) *p++ = (unsigned char)( x ); + *p++ = MBEDTLS_BYTE_2( x ); + if( equals <= 1 ) *p++ = MBEDTLS_BYTE_1( x ); + if( equals <= 0 ) *p++ = MBEDTLS_BYTE_0( x ); } } |