Implement parameter validation for ChaCha/Poly modules

This commit is contained in:
Hanno Becker 2018-12-11 15:03:16 +00:00
parent b3c10b348b
commit 305e4e4f32
3 changed files with 96 additions and 105 deletions

View file

@ -53,6 +53,12 @@
#define inline __inline
#endif
/* Parameter validation macros */
#define CHACHA20_VALIDATE_RET( cond ) \
MBEDTLS_INTERNAL_VALIDATE_RET( cond, MBEDTLS_ERR_CHACHA20_BAD_INPUT_DATA )
#define CHACHA20_VALIDATE( cond ) \
MBEDTLS_INTERNAL_VALIDATE( cond )
#define BYTES_TO_U32_LE( data, offset ) \
( (uint32_t) data[offset] \
| (uint32_t) ( (uint32_t) data[( offset ) + 1] << 8 ) \
@ -181,14 +187,13 @@ static void chacha20_block( const uint32_t initial_state[16],
void mbedtls_chacha20_init( mbedtls_chacha20_context *ctx )
{
if( ctx != NULL )
{
mbedtls_platform_zeroize( ctx->state, sizeof( ctx->state ) );
mbedtls_platform_zeroize( ctx->keystream8, sizeof( ctx->keystream8 ) );
CHACHA20_VALIDATE( ctx != NULL );
/* Initially, there's no keystream bytes available */
ctx->keystream_bytes_used = CHACHA20_BLOCK_SIZE_BYTES;
}
mbedtls_platform_zeroize( ctx->state, sizeof( ctx->state ) );
mbedtls_platform_zeroize( ctx->keystream8, sizeof( ctx->keystream8 ) );
/* Initially, there's no keystream bytes available */
ctx->keystream_bytes_used = CHACHA20_BLOCK_SIZE_BYTES;
}
void mbedtls_chacha20_free( mbedtls_chacha20_context *ctx )
@ -202,10 +207,8 @@ void mbedtls_chacha20_free( mbedtls_chacha20_context *ctx )
int mbedtls_chacha20_setkey( mbedtls_chacha20_context *ctx,
const unsigned char key[32] )
{
if( ( ctx == NULL ) || ( key == NULL ) )
{
return( MBEDTLS_ERR_CHACHA20_BAD_INPUT_DATA );
}
CHACHA20_VALIDATE_RET( ctx != NULL );
CHACHA20_VALIDATE_RET( key != NULL );
/* ChaCha20 constants - the string "expand 32-byte k" */
ctx->state[0] = 0x61707865;
@ -230,10 +233,8 @@ int mbedtls_chacha20_starts( mbedtls_chacha20_context* ctx,
const unsigned char nonce[12],
uint32_t counter )
{
if( ( ctx == NULL ) || ( nonce == NULL ) )
{
return( MBEDTLS_ERR_CHACHA20_BAD_INPUT_DATA );
}
CHACHA20_VALIDATE_RET( ctx != NULL );
CHACHA20_VALIDATE_RET( nonce != NULL );
/* Counter */
ctx->state[12] = counter;
@ -259,15 +260,9 @@ int mbedtls_chacha20_update( mbedtls_chacha20_context *ctx,
size_t offset = 0U;
size_t i;
if( ctx == NULL )
{
return( MBEDTLS_ERR_CHACHA20_BAD_INPUT_DATA );
}
else if( ( size > 0U ) && ( ( input == NULL ) || ( output == NULL ) ) )
{
/* input and output pointers are allowed to be NULL only if size == 0 */
return( MBEDTLS_ERR_CHACHA20_BAD_INPUT_DATA );
}
CHACHA20_VALIDATE_RET( ctx != NULL );
CHACHA20_VALIDATE_RET( size == 0 || input != NULL );
CHACHA20_VALIDATE_RET( size == 0 || output != NULL );
/* Use leftover keystream bytes, if available */
while( size > 0U && ctx->keystream_bytes_used < CHACHA20_BLOCK_SIZE_BYTES )
@ -332,6 +327,11 @@ int mbedtls_chacha20_crypt( const unsigned char key[32],
mbedtls_chacha20_context ctx;
int ret;
CHACHA20_VALIDATE_RET( key != NULL );
CHACHA20_VALIDATE_RET( nonce != NULL );
CHACHA20_VALIDATE_RET( data_len == 0 || input != NULL );
CHACHA20_VALIDATE_RET( data_len == 0 || output != NULL );
mbedtls_chacha20_init( &ctx );
ret = mbedtls_chacha20_setkey( &ctx, key );