From: Ondřej Surý <ondrej@isc.org>
Date: Tue, 12 Sep 2023 14:33:19 +0000 (+0200)
Subject: Use incremental hashing in the isc_sockaddr_hash() function
X-Git-Tag: v9.19.18~75^2~4
X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=9d326aaba32d28674b20c426537c0014dd044318;p=thirdparty%2Fbind9.git

Use incremental hashing in the isc_sockaddr_hash() function

Instead of copying address back and forth when hashing addr+port, we can
use incremental hashing.  Additionally, switch from 64-bit
isc_hash_function to 32-bit isc_hash32() as the resulting value is
32-bit.
---

diff --git a/lib/isc/include/isc/sockaddr.h b/lib/isc/include/isc/sockaddr.h
index 9523865c5ae..b9dda2b0c23 100644
--- a/lib/isc/include/isc/sockaddr.h
+++ b/lib/isc/include/isc/sockaddr.h
@@ -85,7 +85,7 @@ isc_sockaddr_eqaddrprefix(const isc_sockaddr_t *a, const isc_sockaddr_t *b,
  * If 'b''s scope is zero then 'a''s scope will be ignored.
  */
 
-unsigned int
+uint32_t
 isc_sockaddr_hash(const isc_sockaddr_t *sockaddr, bool address_only);
 /*%<
  * Return a hash value for the socket address 'sockaddr'.  If 'address_only'
diff --git a/lib/isc/sockaddr.c b/lib/isc/sockaddr.c
index 765e73e5660..020cc58ae99 100644
--- a/lib/isc/sockaddr.c
+++ b/lib/isc/sockaddr.c
@@ -187,51 +187,49 @@ isc_sockaddr_format(const isc_sockaddr_t *sa, char *array, unsigned int size) {
 	}
 }
 
-unsigned int
+uint32_t
 isc_sockaddr_hash(const isc_sockaddr_t *sockaddr, bool address_only) {
-	unsigned int length = 0;
-	const unsigned char *s = NULL;
-	unsigned int h = 0;
+	REQUIRE(sockaddr != NULL);
+
+	size_t len = 0;
+	const uint8_t *s = NULL;
 	unsigned int p = 0;
 	const struct in6_addr *in6;
+	isc_hash32_t hash;
 
-	REQUIRE(sockaddr != NULL);
+	isc_hash32_init(&hash);
 
 	switch (sockaddr->type.sa.sa_family) {
 	case AF_INET:
-		s = (const unsigned char *)&sockaddr->type.sin.sin_addr;
-		p = ntohs(sockaddr->type.sin.sin_port);
-		length = sizeof(sockaddr->type.sin.sin_addr.s_addr);
+		s = (const uint8_t *)&sockaddr->type.sin.sin_addr;
+		len = sizeof(sockaddr->type.sin.sin_addr.s_addr);
+		if (!address_only) {
+			p = ntohs(sockaddr->type.sin.sin_port);
+		}
 		break;
 	case AF_INET6:
 		in6 = &sockaddr->type.sin6.sin6_addr;
-		s = (const unsigned char *)in6;
+		s = (const uint8_t *)in6;
 		if (IN6_IS_ADDR_V4MAPPED(in6)) {
 			s += 12;
-			length = sizeof(sockaddr->type.sin.sin_addr.s_addr);
+			len = sizeof(sockaddr->type.sin.sin_addr.s_addr);
 		} else {
-			length = sizeof(sockaddr->type.sin6.sin6_addr);
+			len = sizeof(sockaddr->type.sin6.sin6_addr);
+		}
+		if (!address_only) {
+			p = ntohs(sockaddr->type.sin6.sin6_port);
 		}
-		p = ntohs(sockaddr->type.sin6.sin6_port);
 		break;
 	default:
-		UNEXPECTED_ERROR("unknown address family: %d",
-				 (int)sockaddr->type.sa.sa_family);
-		s = (const unsigned char *)&sockaddr->type;
-		length = sockaddr->length;
-		p = 0;
+		UNREACHABLE();
 	}
 
-	uint8_t buf[sizeof(struct sockaddr_storage) + sizeof(p)];
-	memmove(buf, s, length);
+	isc_hash32_hash(&hash, s, len, true);
 	if (!address_only) {
-		memmove(buf + length, &p, sizeof(p));
-		h = isc_hash_function(buf, length + sizeof(p), true);
-	} else {
-		h = isc_hash_function(buf, length, true);
+		isc_hash32_hash(&hash, &p, sizeof(p), true);
 	}
 
-	return (h);
+	return (isc_hash32_finalize(&hash));
 }
 
 void