[PATCH] IPV6: DAD must not have source link-layer option

[YOSHIFUJI Hideaki / 吉藤英明 <yoshfuji@xxxxxxxxxxxxxx>]

Hello.

Check if DAD does not have source link-layer address option;
RFC2461 7.1.1.

Patch depends on "[PATCH] IPV6: DAD has to be destined to 
solicited node mulitcast address" patch.

Thanks.

--- linux25+patch/net/ipv6/ndisc.c.orig Thu Jun 26 04:07:15 2003
+++ linux25+patch/net/ipv6/ndisc.c      Thu Jun 26 04:27:50 2003
@@ -749,15 +749,19 @@ void ndisc_recv_ns(struct sk_buff *skb)
                                printk(KERN_WARNING "ICMP NS: bad lladdr 
length.\n");
                        return;
                }
+
+               /* XXX: RFC2461 7.1.1:
+                *      If the IP source address is the unspecified address, 
+                *      there MUST NOT be source link-layer address option 
+                *      in the message.
+                */
+               if (addr_type == IPV6_ADDR_ANY) {
+                       if (net_ratelimit())
+                               printk(KERN_WARNING "ICMP6 NS: bad DAD packet 
(link-layer address option)\n");
+                       return;
+               }
        }
 
-       /* XXX: RFC2461 7.1.1:
-        *      If the IP source address is the unspecified address, there
-        *      MUST NOT be source link-layer address option in the message.
-        *
-        *      NOTE! Linux kernel < 2.4.4 broke this rule.
-        */
-                       
        if ((ifp = ipv6_get_ifaddr(&msg->target, dev)) != NULL) {
                if (ifp->flags & IFA_F_TENTATIVE) {
                        /* Address is tentative. If the source

-- 
Hideaki YOSHIFUJI @ USAGI Project <yoshfuji@xxxxxxxxxxxxxx>
GPG FP: 9022 65EB 1ECF 3AD1 0BDF  80D8 4807 F894 E062 0EEA