From: Roy Marples <roy@marples.name>
Date: Fri, 17 Jan 2020 21:09:04 +0000 (+0000)
Subject: inet6: Check if we can try a new address on DAD failure.
X-Git-Tag: v9.0.0~99
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=524217dbe3418791f229ad08dce282fcacc624fe;p=thirdparty%2Fdhcpcd.git

inet6: Check if we can try a new address on DAD failure.

Not all prefixes are autoconfable.
---

diff --git a/src/if-linux.c b/src/if-linux.c
index ec7b81e1..2c260d32 100644
--- a/src/if-linux.c
+++ b/src/if-linux.c
@@ -1802,8 +1802,7 @@ if_address6(unsigned char cmd, const struct ipv6_addr *ia)
 #endif
 		}
 #elif IFA_F_MANAGETEMPADDR
-		if (ia->flags & IPV6_AF_AUTOCONF &&
-		    ipv6_ifidlen(ia->iface) + ia->prefix_len == 128)
+		if (ia->flags & IPV6_AF_AUTOCONF && IA6_CANAUTOCONF(ia))
 			flags |= IFA_F_MANAGETEMPADDR;
 #endif
 #ifdef IFA_F_NOPREFIXROUTE
diff --git a/src/ipv6.h b/src/ipv6.h
index 95f9022b..8ffc0896 100644
--- a/src/ipv6.h
+++ b/src/ipv6.h
@@ -69,6 +69,8 @@
 
 /* Interface identifier length. Prefix + this == 128 for autoconf */
 #define ipv6_ifidlen(ifp)	64
+#define	IA6_CANAUTOCONF(ia)	\
+	((ia)->prefix_len + ipv6_ifidlen((ia)->iface) == 128)
 
 #ifndef IN6_ARE_MASKED_ADDR_EQUAL
 #define IN6_ARE_MASKED_ADDR_EQUAL(d, a, m)	(	\
diff --git a/src/ipv6nd.c b/src/ipv6nd.c
index e755244c..82c7be84 100644
--- a/src/ipv6nd.c
+++ b/src/ipv6nd.c
@@ -905,7 +905,9 @@ ipv6nd_dadcallback(void *arg)
 		 * Because ap->dadcounter is always increamented,
 		 * a different address is generated. */
 		/* XXX Cache DAD counter per prefix/id/ssid? */
-		if (ifp->options->options & DHCPCD_SLAACPRIVATE) {
+		if (ifp->options->options & DHCPCD_SLAACPRIVATE &&
+		    IA6_CANAUTOCONF(ia))
+		{
 			unsigned int delay;
 
 			if (ia->dadcounter >= IDGEN_RETRIES) {
@@ -1281,7 +1283,7 @@ ipv6nd_handlera(struct dhcpcd_ctx *ctx,
 			/* RFC4941 Section 3.3.3 */
 			if (ap->flags & IPV6_AF_AUTOCONF &&
 			    ip6_use_tempaddr(ap->iface->name) &&
-			    ipv6_ifidlen(ap->iface) + ap->prefix_len == 128)
+			    IA6_CANAUTOCONF(ap))
 			{
 				if (!new_ap) {
 					if (ipv6_settemptime(ap, 1) == NULL)