Nest: Maintain separate IPv4, IPv6 and LLv6 preferred addresses

Also redesign preferred address selection and update protocols to use
appropriate preferred address.

Based on a previous work by Jan Maria Matejka.

7 files changed, 61 insertions, 77 deletions

diff --git a/proto/babel/babel.c b/proto/babel/babel.c
index a0ec3629..23746155 100644
--- a/proto/babel/babel.c
+++ b/proto/babel/babel.c
@@ -1501,26 +1501,14 @@ babel_add_iface(struct babel_proto *p, struct iface *new, struct babel_iface_con
   ifa->cf = ic;
   ifa->pool = pool;
   ifa->ifname = new->name;
+  ifa->addr = new->llv6->ip;
 
   add_tail(&p->interfaces, NODE ifa);
 
-  ip_addr addr4 = IPA_NONE;
-  struct ifa *addr;
-  WALK_LIST(addr, new->addrs)
-  {
-    if (ipa_is_link_local(addr->ip))
-      ifa->addr = addr->ip;
-
-    if (ipa_zero(addr4) && ipa_is_ip4(addr->ip))
-      addr4 = addr->ip;
-  }
-
+  ip_addr addr4 = new->addr4 ? new->addr4->ip : IPA_NONE;
   ifa->next_hop_ip4 = ipa_nonzero(ic->next_hop_ip4) ? ic->next_hop_ip4 : addr4;
   ifa->next_hop_ip6 = ipa_nonzero(ic->next_hop_ip6) ? ic->next_hop_ip6 : ifa->addr;
 
-  if (ipa_zero(ifa->addr))
-    log(L_WARN "%s: Cannot find link-local addr on %s", p->p.name, new->name);
-
   if (ipa_zero(ifa->next_hop_ip4) && p->ip4_channel)
     log(L_WARN "%s: Cannot find IPv4 next hop addr on %s", p->p.name, new->name);
 
@@ -1576,6 +1564,10 @@ babel_if_notify(struct proto *P, unsigned flags, struct iface *iface)
     if (!(iface->flags & IF_MULTICAST))
       return;
 
+    /* Ignore ifaces without link-local address */
+    if (!iface->llv6)
+      return;
+
     if (ic)
       babel_add_iface(p, iface, ic);
 
@@ -1615,21 +1607,8 @@ babel_reconfigure_iface(struct babel_proto *p, struct babel_iface *ifa, struct b
 
   ifa->cf = new;
 
-  if (ipa_nonzero(new->next_hop_ip4))
-    ifa->next_hop_ip4 = new->next_hop_ip4;
-  else
-  {
-    ifa->next_hop_ip4 = IPA_NONE;
-
-    struct ifa *addr;
-    WALK_LIST(addr, ifa->iface->addrs)
-      if (ipa_is_ip4(addr->ip))
-      {
-	ifa->next_hop_ip4 = addr->ip;
-	break;
-      }
-  }
-
+  ip_addr addr4 = ifa->iface->addr4 ? ifa->iface->addr4->ip : IPA_NONE;
+  ifa->next_hop_ip4 = ipa_nonzero(new->next_hop_ip4) ? new->next_hop_ip4 : addr4;
   ifa->next_hop_ip6 = ipa_nonzero(new->next_hop_ip6) ? new->next_hop_ip6 : ifa->addr;
 
   if (ipa_zero(ifa->next_hop_ip4) && p->ip4_channel)
@@ -1660,7 +1639,15 @@ babel_reconfigure_ifaces(struct babel_proto *p, struct babel_config *cf)
 
   WALK_LIST(iface, iface_list)
   {
-    if (! (iface->flags & IF_UP))
+    if (!(iface->flags & IF_UP))
+      continue;
+
+    /* Ignore non-multicast ifaces */
+    if (!(iface->flags & IF_MULTICAST))
+      continue;
+
+    /* Ignore ifaces without link-local address */
+    if (!iface->llv6)
       continue;
 
     struct babel_iface *ifa = babel_find_iface(p, iface);
diff --git a/proto/babel/packets.c b/proto/babel/packets.c
index 78c133e0..d136efe8 100644
--- a/proto/babel/packets.c
+++ b/proto/babel/packets.c
@@ -1294,7 +1294,7 @@ babel_rx_hook(sock *sk, uint len)
       sk->iface->name, sk->faddr, sk->laddr);
 
   /* Silently ignore my own packets */
-  if (ipa_equal(ifa->iface->addr->ip, sk->faddr))
+  if (ipa_equal(sk->faddr, sk->saddr))
     return 1;
 
   if (!ipa_is_link_local(sk->faddr))
@@ -1329,6 +1329,7 @@ babel_open_socket(struct babel_iface *ifa)
   sk->sport = ifa->cf->port;
   sk->dport = ifa->cf->port;
   sk->iface = ifa->iface;
+  sk->saddr = ifa->addr;
 
   sk->rx_hook = babel_rx_hook;
   sk->tx_hook = babel_tx_hook;
diff --git a/proto/bgp/bgp.c b/proto/bgp/bgp.c
index cccced57..a8d5cf9d 100644
--- a/proto/bgp/bgp.c
+++ b/proto/bgp/bgp.c
@@ -1094,19 +1094,8 @@ bgp_start_neighbor(struct bgp_proto *p)
 
   if (ipa_is_link_local(p->source_addr))
     p->link_addr = p->source_addr;
-  else
-  {
-    /* Find some link-local address for given iface */
-    struct ifa *a;
-    WALK_LIST(a, p->neigh->iface->addrs)
-      if (a->scope == SCOPE_LINK)
-      {
-	p->link_addr = a->ip;
-	break;
-      }
-
-    DBG("%s: Selected link-local address %I\n", p->p.name, p->link_addr);
-  }
+  else if (p->neigh->iface->llv6)
+    p->link_addr = p->neigh->iface->llv6->ip;
 
   bgp_initiate(p);
 }
diff --git a/proto/radv/packets.c b/proto/radv/packets.c
index 15ca5738..9ea8feee 100644
--- a/proto/radv/packets.c
+++ b/proto/radv/packets.c
@@ -358,7 +358,7 @@ radv_rx_hook(sock *sk, uint size)
   if (sk->lifindex != sk->iface->index)
     return 1;
 
-  if (ipa_equal(sk->faddr, ifa->addr->ip))
+  if (ipa_equal(sk->faddr, sk->saddr))
     return 1;
 
   if (size < 8)
diff --git a/proto/radv/radv.c b/proto/radv/radv.c
index b4b1bc58..2c0a23ad 100644
--- a/proto/radv/radv.c
+++ b/proto/radv/radv.c
@@ -138,17 +138,6 @@ radv_iface_add(struct object_lock *lock)
   radv_iface_notify(ifa, RA_EV_INIT);
 }
 
-static inline struct ifa *
-find_lladdr(struct iface *iface)
-{
-  struct ifa *a;
-  WALK_LIST(a, iface->addrs)
-    if ((a->prefix.type == NET_IP6) && (a->scope == SCOPE_LINK))
-      return a;
-
-  return NULL;
-}
-
 static void
 radv_iface_new(struct radv_proto *p, struct iface *iface, struct radv_iface_config *cf)
 {
@@ -161,16 +150,10 @@ radv_iface_new(struct radv_proto *p, struct iface *iface, struct radv_iface_conf
   ifa->ra = p;
   ifa->cf = cf;
   ifa->iface = iface;
+  ifa->addr = iface->llv6;
 
   add_tail(&p->iface_list, NODE ifa);
 
-  ifa->addr = find_lladdr(iface);
-  if (!ifa->addr)
-  {
-    log(L_ERR "%s: Missing link-local address on interface %s", p->p.name, iface->name);
-    return;
-  }
-
   timer *tm = tm_new(pool);
   tm->hook = radv_timer;
   tm->data = ifa;
@@ -216,8 +199,15 @@ radv_if_notify(struct proto *P, unsigned flags, struct iface *iface)
 
   if (flags & IF_CHANGE_UP)
   {
-    struct radv_iface_config *ic = (struct radv_iface_config *)
-      iface_patt_find(&cf->patt_list, iface, NULL);
+    struct radv_iface_config *ic = (void *) iface_patt_find(&cf->patt_list, iface, NULL);
+
+    /* Ignore non-multicast ifaces */
+    if (!(iface->flags & IF_MULTICAST))
+      return;
+
+    /* Ignore ifaces without link-local address */
+    if (!iface->llv6)
+      return;
 
     if (ic)
       radv_iface_new(p, iface, ic);
@@ -395,6 +385,17 @@ radv_reconfigure(struct proto *P, struct proto_config *CF)
   struct iface *iface;
   WALK_LIST(iface, iface_list)
   {
+    if (!(iface->flags & IF_UP))
+      continue;
+
+    /* Ignore non-multicast ifaces */
+    if (!(iface->flags & IF_MULTICAST))
+      continue;
+
+    /* Ignore ifaces without link-local address */
+    if (!iface->llv6)
+      continue;
+
     struct radv_iface *ifa = radv_iface_find(p, iface);
     struct radv_iface_config *ic = (struct radv_iface_config *)
       iface_patt_find(&new->patt_list, iface, NULL);
diff --git a/proto/rip/packets.c b/proto/rip/packets.c
index e97809c8..de48fd0a 100644
--- a/proto/rip/packets.c
+++ b/proto/rip/packets.c
@@ -669,8 +669,7 @@ rip_rx_hook(sock *sk, uint len)
       sk->iface->name, sk->faddr, sk->laddr);
 
   /* Silently ignore my own packets */
-  /* FIXME: Better local address check */
-  if (ipa_equal(ifa->iface->addr->ip, sk->faddr))
+  if (ipa_equal(sk->faddr, sk->saddr))
     return 1;
 
   if (rip_is_ng(p) && !ipa_is_link_local(sk->faddr))
@@ -742,14 +741,7 @@ rip_open_socket(struct rip_iface *ifa)
   sk->sport = ifa->cf->port;
   sk->dport = ifa->cf->port;
   sk->iface = ifa->iface;
-
-  /*
-   * For RIPv2, we explicitly choose a primary address, mainly to ensure that
-   * RIP and BFD uses the same one. For RIPng, we left it to kernel, which
-   * should choose some link-local address based on the same scope rule.
-   */
-  if (rip_is_v2(p))
-    sk->saddr = ifa->iface->addr->ip;
+  sk->saddr = rip_is_v2(p) ? ifa->iface->addr4->ip : ifa->iface->llv6->ip;
 
   sk->rx_hook = rip_rx_hook;
   sk->tx_hook = rip_tx_hook;
diff --git a/proto/rip/rip.c b/proto/rip/rip.c
index 55fb47c5..820c5117 100644
--- a/proto/rip/rip.c
+++ b/proto/rip/rip.c
@@ -630,7 +630,13 @@ rip_add_iface(struct rip_proto *p, struct iface *iface, struct rip_iface_config
   else if (ic->mode == RIP_IM_MULTICAST)
     ifa->addr = rip_is_v2(p) ? IP4_RIP_ROUTERS : IP6_RIP_ROUTERS;
   else /* Broadcast */
-    ifa->addr = iface->addr->brd;
+    ifa->addr = iface->addr4->brd;
+  /*
+   * The above is just a workaround for BSD as it can't send broadcasts
+   * to 255.255.255.255. BSD systems need the network broadcast address instead.
+   *
+   * TODO: move this to sysdep code
+   */
 
   init_list(&ifa->neigh_list);
 
@@ -706,7 +712,11 @@ rip_reconfigure_ifaces(struct rip_proto *p, struct rip_config *cf)
 
   WALK_LIST(iface, iface_list)
   {
-    if (! (iface->flags & IF_UP))
+    if (!(iface->flags & IF_UP))
+      continue;
+
+    /* Ignore ifaces without appropriate address */
+    if (rip_is_v2(p) ? !iface->addr4 : !iface->llv6)
       continue;
 
     struct rip_iface *ifa = rip_find_iface(p, iface);
@@ -744,6 +754,10 @@ rip_if_notify(struct proto *P, unsigned flags, struct iface *iface)
   {
     struct rip_iface_config *ic = (void *) iface_patt_find(&cf->patt_list, iface, NULL);
 
+    /* Ignore ifaces without appropriate address */
+    if (rip_is_v2(p) ? !iface->addr4 : !iface->llv6)
+      return;
+
     if (ic)
       rip_add_iface(p, iface, ic);