Ommit AEAD functions if GCM not defined
diff --git a/library/cipher.c b/library/cipher.c
index a90e2dc..160f4bc 100644
--- a/library/cipher.c
+++ b/library/cipher.c
@@ -425,6 +425,7 @@
return 0;
}
+#if defined(POLARSSL_CIPHER_MODE_AEAD)
int cipher_update_ad( cipher_context_t *ctx,
const unsigned char *ad, size_t ad_len )
{
@@ -444,13 +445,11 @@
return gcm_starts( ctx->cipher_ctx, ctx->operation,
ctx->iv, ctx->iv_size, ad, ad_len );
}
-#else
- ((void) ad);
- ((void) ad_len);
#endif
return 0;
}
+#endif /* POLARSSL_CIPHER_MODE_AEAD */
int cipher_update( cipher_context_t *ctx, const unsigned char *input, size_t ilen,
unsigned char *output, size_t *olen )
@@ -904,50 +903,62 @@
return 0;
}
+#if defined(POLARSSL_CIPHER_MODE_AEAD)
int cipher_write_tag( cipher_context_t *ctx,
unsigned char *tag, size_t tag_len )
{
if( NULL == ctx || NULL == ctx->cipher_info || NULL == tag )
return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA;
- if( POLARSSL_MODE_GCM != ctx->cipher_info->mode )
- return( 0 );
-
if( POLARSSL_ENCRYPT != ctx->operation )
return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA;
- return gcm_finish( ctx->cipher_ctx, tag, tag_len );
+#if defined(POLARSSL_GCM_C)
+ if( POLARSSL_MODE_GCM == ctx->cipher_info->mode )
+ return gcm_finish( ctx->cipher_ctx, tag, tag_len );
+#endif
+
+ return 0;
}
int cipher_check_tag( cipher_context_t *ctx,
const unsigned char *tag, size_t tag_len )
{
int ret;
- unsigned char check_tag[16];
- size_t i;
- int diff;
- if( NULL == ctx || NULL == ctx->cipher_info )
+ if( NULL == ctx || NULL == ctx->cipher_info ||
+ POLARSSL_DECRYPT != ctx->operation )
+ {
return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA;
+ }
- if( POLARSSL_MODE_GCM != ctx->cipher_info->mode )
+#if defined(POLARSSL_GCM_C)
+ if( POLARSSL_MODE_GCM == ctx->cipher_info->mode )
+ {
+ unsigned char check_tag[16];
+ size_t i;
+ int diff;
+
+ if( tag_len > sizeof( check_tag ) )
+ return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA;
+
+ if( 0 != ( ret = gcm_finish( ctx->cipher_ctx, check_tag, tag_len ) ) )
+ return( ret );
+
+ /* Check the tag in "constant-time" */
+ for( diff = 0, i = 0; i < tag_len; i++ )
+ diff |= tag[i] ^ check_tag[i];
+
+ if( diff != 0 )
+ return( POLARSSL_ERR_GCM_AUTH_FAILED );
+
return( 0 );
-
- if( POLARSSL_DECRYPT != ctx->operation || tag_len > sizeof( check_tag ) )
- return POLARSSL_ERR_CIPHER_BAD_INPUT_DATA;
-
- if( 0 != ( ret = gcm_finish( ctx->cipher_ctx, check_tag, tag_len ) ) )
- return( ret );
-
- /* On decryption, check the tag (in "constant-time") */
- for( diff = 0, i = 0; i < tag_len; i++ )
- diff |= tag[i] ^ check_tag[i];
-
- if( diff != 0 )
- return( POLARSSL_ERR_GCM_AUTH_FAILED );
+ }
+#endif
return( 0 );
}
+#endif /* POLARSSL_CIPHER_MODE_AEAD */
#if defined(POLARSSL_SELF_TEST)