X-Git-Url: https://git.cryptolib.org/?a=blobdiff_plain;f=threefish1024_enc.c;h=41a35902d695752987360b67ca5c9e2a5ac91177;hb=b7c1ef29c2b079e52613fd715374f819481810af;hp=4f6f9d46daaa3654fda2d7c986d6e83edced3b15;hpb=4147d732efd04605764a2820d4478f33a0cdf1fa;p=avr-crypto-lib.git

diff --git a/threefish1024_enc.c b/threefish1024_enc.c
index 4f6f9d4..41a3590 100644
--- a/threefish1024_enc.c
+++ b/threefish1024_enc.c
@@ -60,19 +60,23 @@ void permute_16(void* data){
 #define K(s) (((uint64_t*)key)[(s)])
 #define T(s) (((uint64_t*)tweak)[(s)])
 
-void threefish1024_init(void* key, void* tweak, threefish1024_ctx_t* ctx){
+void threefish1024_init(const void* key, const void* tweak, threefish1024_ctx_t* ctx){
 	memcpy(ctx->k, key, 16*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, 0, 3*8);
+	}
 	uint8_t i;
 	ctx->k[16] = THREEFISH_KEY_CONST;
 	for(i=0; i<16; ++i){
 		ctx->k[16] ^= K(i);
 	}
-	ctx->t[2] = T(0) ^ T(1);
 }
 
 static
-void add_key_16(void* data, threefish1024_ctx_t* ctx, uint8_t s){
+void add_key_16(void* data, const threefish1024_ctx_t* ctx, uint8_t s){
 	uint8_t i;
 	for(i=0; i<13; ++i){
 		X(i) += ctx->k[(s+i)%17];
@@ -82,7 +86,7 @@ void add_key_16(void* data, threefish1024_ctx_t* ctx, uint8_t s){
 	X(15) += ctx->k[(s+15)%17] + s;
 }
 
-void threefish1024_enc(void* data, threefish1024_ctx_t* ctx){
+void threefish1024_enc(void* data, const threefish1024_ctx_t* ctx){
 	uint8_t i=0,s=0;
 	uint8_t r0[8] = {55, 25, 33, 34, 28, 17, 58, 47};
 	uint8_t r1[8] = {43, 25,  8, 43,  7,  6,  7, 49};