X-Git-Url: https://git.cryptolib.org/?a=blobdiff_plain;f=threefish512_enc.c;h=620276fed44a24cf2174c7eae8b482e12d0707fe;hb=7701e318e4e2bac7f84dbf6e368f1501814948fc;hp=abd1afc87ee9c4a9718f15f3d4d6d79c0d1f0655;hpb=56a151edecefbaeab43dac22c89a3bb9fe4f470e;p=avr-crypto-lib.git

diff --git a/threefish512_enc.c b/threefish512_enc.c
index abd1afc..620276f 100644
--- a/threefish512_enc.c
+++ b/threefish512_enc.c
@@ -30,18 +30,10 @@
 #include <string.h>
 #include "threefish.h"
 
-#define X0 (((uint64_t*)data)[0])
-#define X1 (((uint64_t*)data)[1])
-static
-void mix(void* data, uint8_t rot){
-	uint64_t x;
-	x = X1;
-	X0 += x;
-	X1 = ((x<<rot)|(x>>(64-rot))) ^ X0;
-}
 
 #define X(a) (((uint64_t*)data)[(a)])
 
+
 static
 void permute_8(void* data){
 	uint64_t t;
@@ -74,19 +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];
@@ -96,7 +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};
@@ -107,10 +103,10 @@ void threefish512_enc(void* data, threefish512_ctx_t* ctx){
 			add_key_8(data, ctx, s);
 			++s;
 		}
-		mix((uint8_t*)data +  0, r0[i%8]);
-		mix((uint8_t*)data + 16, r1[i%8]);
-		mix((uint8_t*)data + 32, r2[i%8]);
-		mix((uint8_t*)data + 48, r3[i%8]);
+		threefish_mix((uint8_t*)data +  0, r0[i%8]);
+		threefish_mix((uint8_t*)data + 16, r1[i%8]);
+		threefish_mix((uint8_t*)data + 32, r2[i%8]);
+		threefish_mix((uint8_t*)data + 48, r3[i%8]);
 		permute_8(data);
 		++i;
 	}while(i!=72);