X-Git-Url: https://git.cryptolib.org/?a=blobdiff_plain;f=threefish512_enc.c;h=620276fed44a24cf2174c7eae8b482e12d0707fe;hb=7701e318e4e2bac7f84dbf6e368f1501814948fc;hp=abb8509e91bb75782e74c9555db5588e20c35dc2;hpb=4147d732efd04605764a2820d4478f33a0cdf1fa;p=avr-crypto-lib.git

diff --git a/threefish512_enc.c b/threefish512_enc.c
index abb8509..620276f 100644
--- a/threefish512_enc.c
+++ b/threefish512_enc.c
@@ -66,19 +66,23 @@ void permute_inv8(void* data){
 #define K(s) (((uint64_t*)key)[(s)])
 #define T(s) (((uint64_t*)tweak)[(s)])
 
-void threefish512_init(void* key, void* tweak, threefish512_ctx_t* ctx){
+void threefish512_init(const void* key, const void* tweak, threefish512_ctx_t* ctx){
 	memcpy(ctx->k, key, 8*8);
-	memcpy(ctx->t, tweak, 2*8);
+	if(tweak){
+		memcpy(ctx->t, tweak, 2*8);
+		ctx->t[2] = T(0) ^ T(1);
+	}else{
+		memset(ctx->t, 0, 3*8);
+	}
 	uint8_t i;
 	ctx->k[8] = THREEFISH_KEY_CONST;
 	for(i=0; i<8; ++i){
 		ctx->k[8] ^= K(i);
 	}
-	ctx->t[2] = T(0) ^ T(1);
 }
 
 static
-void add_key_8(void* data, threefish512_ctx_t* ctx, uint8_t s){
+void add_key_8(void* data, const threefish512_ctx_t* ctx, uint8_t s){
 	uint8_t i;
 	for(i=0; i<5; ++i){
 		X(i) += ctx->k[(s+i)%9];
@@ -88,7 +92,7 @@ void add_key_8(void* data, threefish512_ctx_t* ctx, uint8_t s){
 	X(7) += ctx->k[(s+7)%9] + s;
 }
 
-void threefish512_enc(void* data, threefish512_ctx_t* ctx){
+void threefish512_enc(void* data, const threefish512_ctx_t* ctx){
 	uint8_t i=0,s=0;
 	uint8_t r0[8] = {38, 48, 34, 26, 33, 39, 29, 33}; 
 	uint8_t r1[8] = {30, 20, 14, 12, 49, 27, 26, 51};