From b02bbf237cfd36cd736cefc78f1e3ba3278dc7bf Mon Sep 17 00:00:00 2001
From: Kai Blin <kai@samba.org>
Date: Sat, 24 Sep 2011 18:18:14 -0700
Subject: net: Don't register link local addresses with DNS

---
 lib/util/util_net.c | 23 +++++++++++++++++++++++
 lib/util/util_net.h |  1 +
 2 files changed, 24 insertions(+)

(limited to 'lib/util')

diff --git a/lib/util/util_net.c b/lib/util/util_net.c
index 23d25acab9..139c9d42bc 100644
--- a/lib/util/util_net.c
+++ b/lib/util/util_net.c
@@ -432,6 +432,29 @@ void zero_ip_v4(struct in_addr *ip)
 	ZERO_STRUCTP(ip);
 }
 
+bool is_linklocal_addr(const struct sockaddr_storage *pss)
+{
+#ifdef HAVE_IPV6
+	if (pss->ss_family == AF_INET6) {
+		const struct in6_addr *pin6 =
+			&((const struct sockaddr_in6 *)pss)->sin6_addr;
+		return IN6_IS_ADDR_LINKLOCAL(pin6);
+	}
+#endif
+	if (pss->ss_family == AF_INET) {
+		const struct in_addr *pin =
+			&((const struct sockaddr_in *)pss)->sin_addr;
+		struct in_addr ll_addr;
+		struct in_addr mask_addr;
+
+		/* 169.254.0.0/16, is link local, see RFC 3927 */
+		ll_addr.s_addr = 0xa9fe0000;
+		mask_addr.s_addr = 0xffff0000;
+		return same_net_v4(*pin, ll_addr, mask_addr);
+	}
+	return false;
+}
+
 /**
  * Convert an IPv4 struct in_addr to a struct sockaddr_storage.
  */
diff --git a/lib/util/util_net.h b/lib/util/util_net.h
index fc2776a32b..215a6574d4 100644
--- a/lib/util/util_net.h
+++ b/lib/util/util_net.h
@@ -74,6 +74,7 @@ bool is_loopback_ip_v4(struct in_addr ip);
 bool is_loopback_addr(const struct sockaddr *pss);
 bool is_zero_addr(const struct sockaddr_storage *pss);
 void zero_ip_v4(struct in_addr *ip);
+bool is_linklocal_addr(const struct sockaddr_storage *pss);
 /**
  Interpret an internet address or name into an IP address in 4 byte form.
 **/
-- 
cgit