X-Git-Url: https://git.cryptolib.org/?a=blobdiff_plain;f=host%2Fgf256mul.c;h=b3dd4605a44b1bd7adcffe983b8b12556077ccf2;hb=69d6349f8ad9d35c2acdb4e4e38ad42cd28b426c;hp=3da67cb53fc0e6a8087124dce458aa1c702ce723;hpb=b3daeff2bc9d451afc9c311034a122c6495cc1ab;p=avr-crypto-lib.git

diff --git a/host/gf256mul.c b/host/gf256mul.c
index 3da67cb..b3dd460 100644
--- a/host/gf256mul.c
+++ b/host/gf256mul.c
@@ -1,6 +1,6 @@
 /* gf256mul.c */
 /*
-    This file is part of the Crypto-avr-lib/microcrypt-lib.
+    This file is part of the AVR-Crypto-Lib.
     Copyright (C) 2008  Daniel Otte (daniel.otte@rub.de)
 
     This program is free software: you can redistribute it and/or modify
@@ -28,15 +28,16 @@
 #include "gf256mul.h"
 
 uint8_t gf256mul(uint8_t a, uint8_t b, uint8_t reducer){
-	uint8_t t,ret=0;
-	while(a){
-		if(a&1)
-			ret ^= b;
+	uint8_t i;
+	uint8_t p=0,t;
+	for(i=0; i<8; ++i){
+		if(b&1)
+			p ^= a;
 		t=a&0x80;
-		b<<=1;
+		a<<=1;
 		if(t)
-			b^=reducer;
-		a>>=1;
+			a ^= reducer;
+		b>>=1;
 	}
-	return ret;
+	return p;
 }