Optimise unneccesary cf table accesses away
Also fix missed bare access of base_64_dec_map
@@ -207,6 +207,7 @@ 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++ )
@@ -237,11 +238,12 @@ 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 ||
- mbedtls_base64_table_lookup( base64_dec_map, sizeof( 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++;
@@ -271,9 +273,10 @@ int mbedtls_base64_decode( unsigned char *dst, size_t dlen, size_t *olen,
if( *src == '\r' || *src == '\n' || *src == ' ' )
continue;
- j -= ( mbedtls_base64_table_lookup(base64_dec_map, sizeof( base64_dec_map ), *src ) == 64 );
- x = ( x << 6 ) |
- ( mbedtls_base64_table_lookup( base64_dec_map, sizeof( base64_dec_map ), *src ) & 0x3F );
+ dec_map_lookup = mbedtls_base64_table_lookup(base64_dec_map, sizeof( base64_dec_map ), *src );
+
+ j -= ( dec_map_lookup == 64 );
+ x = ( x << 6 ) | ( dec_map_lookup & 0x3F );
if( ++n == 4 )
{
