2 files changed, 13 insertions, 0 deletions
diff --git a/lib/ipv6.c b/lib/ipv6.c
index b666ddd8..88c54eb6 100644
--- a/lib/ipv6.c
+++ b/lib/ipv6.c
@@ -322,6 +322,17 @@ ip_pton(char *a, ip_addr *o)
   return 1;
 }
 
+void ipv6_absolutize(ip_addr *a, ip_addr *ifa)
+{
+  if ((a->addr[0] & 0xffc00000) == 0xfe800000 &&	/* a is link-scope */
+      ((ifa->addr[0] & 0xe0000000) == 0x20000000 |	/* ifa is AGU ... */
+       (ifa->addr[0] & 0xffc00000) == 0xfec00000))	/* ... or site-scope */
+    {
+      a->addr[0] = ifa->addr[0];	/* Copy the prefix, leave interface ID */
+      a->addr[1] = ifa->addr[1];
+    }
+}
+
 #ifdef TEST
 
 #include "bitops.c"
diff --git a/lib/ipv6.h b/lib/ipv6.h
index cf7a9bbe..90aedb94 100644
--- a/lib/ipv6.h
+++ b/lib/ipv6.h
@@ -55,6 +55,7 @@ typedef struct ipv6_addr {
 /* ipa_from_u32 and ipa_to_u32 replaced by ipa_build */
 #define ipa_build(a,b,c,d) _MI(a,b,c,d)
 #define ipa_compare(x,y) ipv6_compare(x,y)
+#define ipa_absolutize(x,y) ipv6_absolutize(x,y)
 
 ip_addr ipv6_mkmask(unsigned);
 unsigned ipv6_mklen(ip_addr *);
@@ -63,6 +64,7 @@ void ipv6_hton(ip_addr *);
 void ipv6_ntoh(ip_addr *);
 int ipv6_compare(ip_addr, ip_addr);
 int ipv4_pton_u32(char *, u32 *);
+void ipv6_absolutize(ip_addr *, ip_addr *);
 
 /*
  *  This hash function looks well, but once IPv6 enters