eden-emu/mbedtls
14
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Merge branch 'mbedtls-2.16-restricted' into mbedtls-2.16.10-rc

Browse source
This commit is contained in:
Dave Rodgman 2021-03-08 16:46:51 +00:00
commit 2ed6fe0b30
4 changed files with 159 additions and 13 deletions
Download patch file Download diff file Expand all files Collapse all files

131
library/base64.c
View file

@ -96,6 +96,99 @@ static const unsigned char base64_dec_map[128] =
#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
*/
@ -136,10 +229,17 @@ int mbedtls_base64_encode( unsigned char *dst, size_t dlen, size_t *olen,
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];
*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 ) );
}
if( i < slen )
@ -147,11 +247,15 @@ int mbedtls_base64_encode( unsigned char *dst, size_t dlen, size_t *olen,
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];
*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 ) );
if( ( i + 1 ) < slen )
*p++ = base64_enc_map[((C2 & 15) << 2) & 0x3F];
*p++ = mbedtls_base64_table_lookup( base64_enc_map, sizeof( base64_enc_map ),
( ( ( C2 & 15 ) << 2 ) & 0x3F ) );
else *p++ = '=';
*p++ = '=';
@ -172,6 +276,7 @@ int mbedtls_base64_decode( unsigned char *dst, size_t dlen, size_t *olen,
size_t i, n;
uint32_t j, x;
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++ )
@ -202,10 +307,12 @@ int mbedtls_base64_decode( unsigned char *dst, size_t dlen, size_t *olen,
if( src[i] == '=' && ++j > 2 )
return( MBEDTLS_ERR_BASE64_INVALID_CHARACTER );
if( src[i] > 127 || base64_dec_map[src[i]] == 127 )
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( base64_dec_map[src[i]] < 64 && j != 0 )
if( dec_map_lookup < 64 && j != 0 )
return( MBEDTLS_ERR_BASE64_INVALID_CHARACTER );
n++;
@ -235,8 +342,10 @@ int mbedtls_base64_decode( unsigned char *dst, size_t dlen, size_t *olen,
if( *src == '\r' || *src == '\n' || *src == ' ' )
continue;
j -= ( base64_dec_map[*src] == 64 );
x = ( x << 6 ) | ( base64_dec_map[*src] & 0x3F );
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 );
if( ++n == 4 )
{