ip6: use vlanid if present in working out stable private addresses

dhcpcd doesn't allow address sharing currently, so this is a
needed change for vlan users.

diff --git a/src/ipv6.c b/src/ipv6.c
index b3b026b320260b026557843ad6c72aefb8a0e97c..2d516d99315e44a9ab1b4bfa40f1064e78d15ca3 100644 (file)
--- a/src/ipv6.c
+++ b/src/ipv6.c
@@ -253,6 +253,7 @@ ipv6_makestableprivate1(struct in6_addr *addr,
     const struct in6_addr *prefix, int prefix_len,
     const unsigned char *netiface, size_t netiface_len,
     const unsigned char *netid, size_t netid_len,
+    unsigned short vlanid,
     uint32_t *dad_counter,
     const unsigned char *secret, size_t secret_len)
 {
@@ -267,6 +268,8 @@ ipv6_makestableprivate1(struct in6_addr *addr,
 
        l = (size_t)(ROUNDUP8(prefix_len) / NBBY);
        len = l + netiface_len + netid_len + sizeof(*dad_counter) + secret_len;
+       if (vlanid != 0)
+               len += sizeof(vlanid);
        if (len > sizeof(buf)) {
                errno = ENOBUFS;
                return -1;
@@ -281,6 +284,12 @@ ipv6_makestableprivate1(struct in6_addr *addr,
                p += netiface_len;
                memcpy(p, netid, netid_len);
                p += netid_len;
+               /* Don't use a vlanid if not set.
+                * This ensures prior versions have the same unique address. */
+               if (vlanid != 0) {
+                       memcpy(p, &vlanid, sizeof(vlanid));
+                       p += sizeof(vlanid);
+               }
                memcpy(p, dad_counter, sizeof(*dad_counter));
                p += sizeof(*dad_counter);
                memcpy(p, secret, secret_len);
@@ -333,7 +342,7 @@ ipv6_makestableprivate(struct in6_addr *addr,
        r = ipv6_makestableprivate1(addr, prefix, prefix_len,
            ifp->hwaddr, ifp->hwlen,
            ifp->ssid, ifp->ssid_len,
-           &dad,
+           ifp->vlanid, &dad,
            ifp->ctx->secret, ifp->ctx->secret_len);
 
        if (r == 0)