Fix skein256/skein512 issue where an empty bytestring trigger state c…

…hange If an empty bytestring is use to call update, it could trigger the processing of the buf, that could be holding the data for finalize (the last block). That would give bad calculations.
vincenthz · Mar 27, 2014 · 0999082 · 0999082
1 parent 0f9a9c0
commit 0999082
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diff --git a/cbits/skein256.c b/cbits/skein256.c
@@ -124,6 +124,9 @@ void skein256_update(struct skein256_ctx *ctx, uint8_t *data, uint32_t len)
 {
 	uint32_t to_fill;
 
+	if (!len)
+		return;
+
 	to_fill = 32 - ctx->bufindex;
 
 	if (ctx->bufindex == 32) {

diff --git a/cbits/skein512.c b/cbits/skein512.c
@@ -142,6 +142,9 @@ void skein512_update(struct skein512_ctx *ctx, uint8_t *data, uint32_t len)
 {
 	uint32_t to_fill;
 
+	if (!len)
+		return;
+
 	to_fill = 64 - ctx->bufindex;
 
 	if (ctx->bufindex == 64) {