Allow some parameters to be NULL if the length is 0.
This change permits users of the ChaCha20/Poly1305 algorithms
(and the AEAD construction thereof) to pass NULL pointers for
data that they do not need, and avoids the need to provide a valid
buffer for data that is not used.
diff --git a/library/aead_chacha20_poly1305.c b/library/aead_chacha20_poly1305.c
index ab29dfa..2dea5c9 100644
--- a/library/aead_chacha20_poly1305.c
+++ b/library/aead_chacha20_poly1305.c
@@ -174,10 +174,15 @@
size_t aad_len,
const unsigned char *aad )
{
- if ( ( ctx == NULL ) || ( aad == NULL ) )
+ if ( ctx == NULL )
{
return( MBEDTLS_ERR_AEAD_CHACHA20_POLY1305_BAD_INPUT_DATA );
}
+ else if ( ( aad_len > 0U ) && ( aad == NULL ) )
+ {
+ /* aad pointer is allowed to be NULL if aad_len == 0 */
+ return( MBEDTLS_ERR_AEAD_CHACHA20_POLY1305_BAD_INPUT_DATA );
+ }
else if ( ctx->state != AEAD_CHACHA20_POLY1305_STATE_AAD )
{
return (MBEDTLS_ERR_AEAD_CHACHA20_POLY1305_BAD_STATE );
@@ -197,6 +202,11 @@
{
return( MBEDTLS_ERR_AEAD_CHACHA20_POLY1305_BAD_INPUT_DATA );
}
+ else if ( ( len > 0U ) && ( ( input == NULL ) || ( output == NULL ) ) )
+ {
+ /* input and output pointers are allowed to be NULL if len == 0 */
+ return( MBEDTLS_ERR_AEAD_CHACHA20_POLY1305_BAD_INPUT_DATA );
+ }
else if ( ( ctx->state != AEAD_CHACHA20_POLY1305_STATE_AAD ) &&
( ctx->state != AEAD_CHACHA20_POLY1305_STATE_CIPHERTEXT ) )
{