X-Git-Url: http://pileus.org/git/?a=blobdiff_plain;f=crypto%2Fmemneq.c;h=afed1bd16aee0b53f63a4bdc11aecab56927821d;hb=08d21b5f93eb92a781daea71b6fcb3a340909141;hp=cd0162221c141855fcaf1920ceb9466a6baf875a;hpb=81e53d0470878165a300d75ac06a5bc5eee543a2;p=~andy%2Flinux

diff --git a/crypto/memneq.c b/crypto/memneq.c
index cd0162221c1..afed1bd16ae 100644
--- a/crypto/memneq.c
+++ b/crypto/memneq.c
@@ -72,6 +72,7 @@ __crypto_memneq_generic(const void *a, const void *b, size_t size)
 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
 	while (size >= sizeof(unsigned long)) {
 		neq |= *(unsigned long *)a ^ *(unsigned long *)b;
+		OPTIMIZER_HIDE_VAR(neq);
 		a += sizeof(unsigned long);
 		b += sizeof(unsigned long);
 		size -= sizeof(unsigned long);
@@ -79,6 +80,7 @@ __crypto_memneq_generic(const void *a, const void *b, size_t size)
 #endif /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */
 	while (size > 0) {
 		neq |= *(unsigned char *)a ^ *(unsigned char *)b;
+		OPTIMIZER_HIDE_VAR(neq);
 		a += 1;
 		b += 1;
 		size -= 1;
@@ -89,33 +91,61 @@ __crypto_memneq_generic(const void *a, const void *b, size_t size)
 /* Loop-free fast-path for frequently used 16-byte size */
 static inline unsigned long __crypto_memneq_16(const void *a, const void *b)
 {
+	unsigned long neq = 0;
+
 #ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
-	if (sizeof(unsigned long) == 8)
-		return ((*(unsigned long *)(a)   ^ *(unsigned long *)(b))
-		      | (*(unsigned long *)(a+8) ^ *(unsigned long *)(b+8)));
-	else if (sizeof(unsigned int) == 4)
-		return ((*(unsigned int *)(a)    ^ *(unsigned int *)(b))
-                      | (*(unsigned int *)(a+4)  ^ *(unsigned int *)(b+4))
-		      | (*(unsigned int *)(a+8)  ^ *(unsigned int *)(b+8))
-	              | (*(unsigned int *)(a+12) ^ *(unsigned int *)(b+12)));
-	else
+	if (sizeof(unsigned long) == 8) {
+		neq |= *(unsigned long *)(a)   ^ *(unsigned long *)(b);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned long *)(a+8) ^ *(unsigned long *)(b+8);
+		OPTIMIZER_HIDE_VAR(neq);
+	} else if (sizeof(unsigned int) == 4) {
+		neq |= *(unsigned int *)(a)    ^ *(unsigned int *)(b);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned int *)(a+4)  ^ *(unsigned int *)(b+4);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned int *)(a+8)  ^ *(unsigned int *)(b+8);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned int *)(a+12) ^ *(unsigned int *)(b+12);
+		OPTIMIZER_HIDE_VAR(neq);
+	} else
 #endif /* CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS */
-		return ((*(unsigned char *)(a)    ^ *(unsigned char *)(b))
-		      | (*(unsigned char *)(a+1)  ^ *(unsigned char *)(b+1))
-		      | (*(unsigned char *)(a+2)  ^ *(unsigned char *)(b+2))
-		      | (*(unsigned char *)(a+3)  ^ *(unsigned char *)(b+3))
-		      | (*(unsigned char *)(a+4)  ^ *(unsigned char *)(b+4))
-		      | (*(unsigned char *)(a+5)  ^ *(unsigned char *)(b+5))
-		      | (*(unsigned char *)(a+6)  ^ *(unsigned char *)(b+6))
-		      | (*(unsigned char *)(a+7)  ^ *(unsigned char *)(b+7))
-		      | (*(unsigned char *)(a+8)  ^ *(unsigned char *)(b+8))
-		      | (*(unsigned char *)(a+9)  ^ *(unsigned char *)(b+9))
-		      | (*(unsigned char *)(a+10) ^ *(unsigned char *)(b+10))
-		      | (*(unsigned char *)(a+11) ^ *(unsigned char *)(b+11))
-		      | (*(unsigned char *)(a+12) ^ *(unsigned char *)(b+12))
-		      | (*(unsigned char *)(a+13) ^ *(unsigned char *)(b+13))
-		      | (*(unsigned char *)(a+14) ^ *(unsigned char *)(b+14))
-		      | (*(unsigned char *)(a+15) ^ *(unsigned char *)(b+15)));
+	{
+		neq |= *(unsigned char *)(a)    ^ *(unsigned char *)(b);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned char *)(a+1)  ^ *(unsigned char *)(b+1);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned char *)(a+2)  ^ *(unsigned char *)(b+2);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned char *)(a+3)  ^ *(unsigned char *)(b+3);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned char *)(a+4)  ^ *(unsigned char *)(b+4);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned char *)(a+5)  ^ *(unsigned char *)(b+5);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned char *)(a+6)  ^ *(unsigned char *)(b+6);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned char *)(a+7)  ^ *(unsigned char *)(b+7);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned char *)(a+8)  ^ *(unsigned char *)(b+8);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned char *)(a+9)  ^ *(unsigned char *)(b+9);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned char *)(a+10) ^ *(unsigned char *)(b+10);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned char *)(a+11) ^ *(unsigned char *)(b+11);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned char *)(a+12) ^ *(unsigned char *)(b+12);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned char *)(a+13) ^ *(unsigned char *)(b+13);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned char *)(a+14) ^ *(unsigned char *)(b+14);
+		OPTIMIZER_HIDE_VAR(neq);
+		neq |= *(unsigned char *)(a+15) ^ *(unsigned char *)(b+15);
+		OPTIMIZER_HIDE_VAR(neq);
+	}
+
+	return neq;
 }
 
 /* Compare two areas of memory without leaking timing information,