Initial commit on integrated BIRD

New data types net_addr and variants (in lib/net.h) describing
network addresses (prefix/pxlen). Modifications of FIB structures
to handle these data types and changing everything to use these
data types instead of prefix/pxlen pairs where possible.

The commit is WiP, some protocols are not yet updated (BGP, Kernel),
and the code contains some temporary scaffolding.

Comments are welcome.

3 files changed, 54 insertions, 61 deletions

diff --git a/proto/rip/packets.c b/proto/rip/packets.c
index be20734f..e2a2390b 100644
--- a/proto/rip/packets.c
+++ b/proto/rip/packets.c
@@ -78,8 +78,7 @@ struct rip_auth_tail
 /* Internal representation of RTE block data */
 struct rip_block
 {
-  ip_addr prefix;
-  int pxlen;
+  net_addr net;
   u32 metric;
   u16 tag;
   u16 no_af;
@@ -115,17 +114,17 @@ rip_put_block(struct rip_proto *p, byte *pos, struct rip_block *rte)
     struct rip_block_v2 *block = (void *) pos;
     block->family = rte->no_af ? 0 : htons(RIP_AF_IPV4);
     block->tag = htons(rte->tag);
-    block->network = ip4_hton(ipa_to_ip4(rte->prefix));
-    block->netmask = ip4_hton(ip4_mkmask(rte->pxlen));
+    block->network = ip4_hton(net4_prefix(&rte->net));
+    block->netmask = ip4_hton(ip4_mkmask(net4_pxlen(&rte->net)));
     block->next_hop = ip4_hton(ipa_to_ip4(rte->next_hop));
     block->metric = htonl(rte->metric);
   }
   else /* RIPng */
   {
     struct rip_block_ng *block = (void *) pos;
-    block->prefix = ip6_hton(ipa_to_ip6(rte->prefix));
+    block->prefix = ip6_hton(net6_prefix(&rte->net));
     block->tag = htons(rte->tag);
-    block->pxlen = rte->pxlen;
+    block->pxlen = net6_pxlen(&rte->net);
     block->metric = rte->metric;
   }
 }
@@ -151,8 +150,8 @@ rip_get_block(struct rip_proto *p, byte *pos, struct rip_block *rte)
     if (block->family != (rte->no_af ? 0 : htons(RIP_AF_IPV4)))
       return 0;
 
-    rte->prefix = ipa_from_ip4(ip4_ntoh(block->network));
-    rte->pxlen = ip4_masklen(ip4_ntoh(block->netmask));
+    uint pxlen = ip4_masklen(ip4_ntoh(block->netmask));
+    net_fill_ip4(&rte->net, ip4_ntoh(block->network), pxlen);
     rte->metric = ntohl(block->metric);
     rte->tag = ntohs(block->tag);
     rte->next_hop = ipa_from_ip4(ip4_ntoh(block->next_hop));
@@ -171,8 +170,8 @@ rip_get_block(struct rip_proto *p, byte *pos, struct rip_block *rte)
       return 0;
     }
 
-    rte->prefix = ipa_from_ip6(ip6_ntoh(block->prefix));
-    rte->pxlen = block->pxlen;
+    uint pxlen = (block->pxlen < IP6_MAX_PREFIX_LENGTH) ? block->pxlen : 255;
+    net_fill_ip6(&rte->net, ip6_ntoh(block->prefix), pxlen);
     rte->metric = block->metric;
     rte->tag = ntohs(block->tag);
     /* rte->next_hop is deliberately kept unmodified */;
@@ -385,8 +384,9 @@ rip_receive_request(struct rip_proto *p, struct rip_iface *ifa, struct rip_packe
   if (!rip_get_block(p, pos, &b))
     return;
 
-  /* Special case - zero prefix, infinity metric */
-  if (ipa_nonzero(b.prefix) || b.pxlen || (b.metric != p->infinity))
+  /* Special case - infinity metric, for RIPng also zero prefix */
+  if ((b.metric != p->infinity) ||
+      (rip_is_ng(p) && !net_zero_ip6((net_addr_ip6 *) &b.net)))
     return;
 
   /* We do nothing if TX is already active */
@@ -444,23 +444,23 @@ rip_send_response(struct rip_proto *p, struct rip_iface *ifa)
     }
 
     struct rip_block rte = {
-      .prefix = en->n.prefix,
-      .pxlen = en->n.pxlen,
       .metric = en->metric,
       .tag = en->tag
     };
 
+    net_copy(&rte.net, en->n.addr);
+
     if (en->iface == ifa->iface)
       rte.next_hop = en->next_hop;
 
     if (rip_is_v2(p) && (ifa->cf->version == RIP_V1))
     {
       /* Skipping subnets (i.e. not hosts, classful networks or default route) */
-      if (ip4_masklen(ip4_class_mask(ipa_to_ip4(en->n.prefix))) != en->n.pxlen)
+      if (ip4_masklen(ip4_class_mask(net4_prefix(&rte.net))) != rte.net.pxlen)
 	goto next_entry;
 
       rte.tag = 0;
-      rte.pxlen = 0;
+      rte.net.pxlen = 0;
       rte.next_hop = IPA_NONE;
     }
 
@@ -476,7 +476,7 @@ rip_send_response(struct rip_proto *p, struct rip_iface *ifa)
 	goto next_entry;
     }
 
-    // TRACE(D_PACKETS, "    %I/%d -> %I metric %d", rte.prefix, rte.pxlen, rte.next_hop, rte.metric);
+    // TRACE(D_PACKETS, "    %N -> %I metric %d", &rte.net, rte.next_hop, rte.metric);
 
     /* RIPng next hop entry */
     if (rip_is_ng(p) && !ipa_equal(rte.next_hop, last_next_hop))
@@ -577,23 +577,25 @@ rip_receive_response(struct rip_proto *p, struct rip_iface *ifa, struct rip_pack
     if (!rip_get_block(p, pos, &rte))
       continue;
 
-    int c = ipa_classify_net(rte.prefix);
-    if ((c < 0) || !(c & IADDR_HOST) || ((c & IADDR_SCOPE_MASK) <= SCOPE_LINK))
-      SKIP("invalid prefix");
-
     if (rip_is_v2(p) && (pkt->version == RIP_V1))
     {
-      if (ifa->cf->check_zero && (rte.tag || rte.pxlen || ipa_nonzero(rte.next_hop)))
+      if (ifa->cf->check_zero && (rte.tag || rte.net.pxlen || ipa_nonzero(rte.next_hop)))
 	SKIP("RIPv1 reserved field is nonzero");
 
       rte.tag = 0;
-      rte.pxlen = ip4_masklen(ip4_class_mask(ipa_to_ip4(rte.prefix)));
+      rte.net.pxlen = ip4_masklen(ip4_class_mask(net4_prefix(&rte.net)));
       rte.next_hop = IPA_NONE;
     }
 
-    if ((rte.pxlen < 0) || (rte.pxlen > MAX_PREFIX_LENGTH))
+    if (rte.net.pxlen == 255)
       SKIP("invalid prefix length");
 
+    net_normalize(&rte.net);
+
+    int c = net_classify(&rte.net);
+    if ((c < 0) || !(c & IADDR_HOST) || ((c & IADDR_SCOPE_MASK) <= SCOPE_LINK))
+      SKIP("invalid prefix");
+
     if (rte.metric > p->infinity)
       SKIP("invalid metric");
 
@@ -604,7 +606,7 @@ rip_receive_response(struct rip_proto *p, struct rip_iface *ifa, struct rip_pack
 	rte.next_hop = IPA_NONE;
     }
 
-    // TRACE(D_PACKETS, "    %I/%d -> %I metric %d", rte.prefix, rte.pxlen, rte.next_hop, rte.metric);
+    // TRACE(D_PACKETS, "    %N -> %I metric %d", &rte.net.n, rte.next_hop, rte.metric);
 
     rte.metric += ifa->cf->metric;
 
@@ -618,16 +620,16 @@ rip_receive_response(struct rip_proto *p, struct rip_iface *ifa, struct rip_pack
 	.expires = now + ifa->cf->timeout_time
       };
 
-      rip_update_rte(p, &rte.prefix, rte.pxlen, &new);
+      rip_update_rte(p, &rte.net, &new);
     }
     else
-      rip_withdraw_rte(p, &rte.prefix, rte.pxlen, from);
+      rip_withdraw_rte(p, &rte.net, from);
 
     continue;
 
   skip:
-    LOG_RTE("Ignoring route %I/%d received from %I - %s",
-	    rte.prefix, rte.pxlen, from->nbr->addr, err_dsc);
+    LOG_RTE("Ignoring route %N received from %I - %s",
+	    &rte.net, from->nbr->addr, err_dsc);
   }
 }
 
diff --git a/proto/rip/rip.c b/proto/rip/rip.c
index c85fd69b..d8c3b6a8 100644
--- a/proto/rip/rip.c
+++ b/proto/rip/rip.c
@@ -92,15 +92,6 @@ static void rip_trigger_update(struct rip_proto *p);
  *	RIP routes
  */
 
-static void
-rip_init_entry(struct fib_node *fn)
-{
-  // struct rip_entry *en = (void) *fn;
-
-  const uint offset = OFFSETOF(struct rip_entry, routes);
-  memset((byte *)fn + offset, 0, sizeof(struct rip_entry) - offset);
-}
-
 static struct rip_rte *
 rip_add_rte(struct rip_proto *p, struct rip_rte **rp, struct rip_rte *src)
 {
@@ -152,7 +143,7 @@ rip_announce_rte(struct rip_proto *p, struct rip_entry *en)
   if (rt)
   {
     /* Update */
-    net *n = net_get(p->p.table, en->n.prefix, en->n.pxlen);
+    net *n = net_get(p->p.table, en->n.addr);
 
     rta a0 = {
       .src = p->p.main_source,
@@ -221,7 +212,7 @@ rip_announce_rte(struct rip_proto *p, struct rip_entry *en)
   else
   {
     /* Withdraw */
-    net *n = net_find(p->p.table, en->n.prefix, en->n.pxlen);
+    net *n = net_find(p->p.table, en->n.addr);
     rte_update(&p->p, n, NULL);
   }
 }
@@ -229,8 +220,7 @@ rip_announce_rte(struct rip_proto *p, struct rip_entry *en)
 /**
  * rip_update_rte - enter a route update to RIP routing table
  * @p: RIP instance
- * @prefix: network prefix
- * @pxlen: network prefix length
+ * @addr: network address
  * @new: a &rip_rte representing the new route
  *
  * The function is called by the RIP packet processing code whenever it receives
@@ -240,9 +230,9 @@ rip_announce_rte(struct rip_proto *p, struct rip_entry *en)
  * rip_withdraw_rte() should be called instead of rip_update_rte().
  */
 void
-rip_update_rte(struct rip_proto *p, ip_addr *prefix, int pxlen, struct rip_rte *new)
+rip_update_rte(struct rip_proto *p, net_addr *n, struct rip_rte *new)
 {
-  struct rip_entry *en = fib_get(&p->rtable, prefix, pxlen);
+  struct rip_entry *en = fib_get(&p->rtable, n);
   struct rip_rte *rt, **rp;
   int changed = 0;
 
@@ -282,8 +272,7 @@ rip_update_rte(struct rip_proto *p, ip_addr *prefix, int pxlen, struct rip_rte *
 /**
  * rip_withdraw_rte - enter a route withdraw to RIP routing table
  * @p: RIP instance
- * @prefix: network prefix
- * @pxlen: network prefix length
+ * @addr: network address
  * @from: a &rip_neighbor propagating the withdraw
  *
  * The function is called by the RIP packet processing code whenever it receives
@@ -291,9 +280,9 @@ rip_update_rte(struct rip_proto *p, ip_addr *prefix, int pxlen, struct rip_rte *
  * removed. Eventually, the change is also propagated by rip_announce_rte().
  */
 void
-rip_withdraw_rte(struct rip_proto *p, ip_addr *prefix, int pxlen, struct rip_neighbor *from)
+rip_withdraw_rte(struct rip_proto *p, net_addr *n, struct rip_neighbor *from)
 {
-  struct rip_entry *en = fib_find(&p->rtable, prefix, pxlen);
+  struct rip_entry *en = fib_find(&p->rtable, n);
   struct rip_rte *rt, **rp;
 
   if (!en)
@@ -335,15 +324,15 @@ rip_rt_notify(struct proto *P, struct rtable *table UNUSED, struct network *net,
 
     if (rt_metric > p->infinity)
     {
-      log(L_WARN "%s: Invalid rip_metric value %u for route %I/%d",
-	  p->p.name, rt_metric, net->n.prefix, net->n.pxlen);
+      log(L_WARN "%s: Invalid rip_metric value %u for route %N",
+	  p->p.name, rt_metric, net->n.addr);
       rt_metric = p->infinity;
     }
 
     if (rt_tag > 0xffff)
     {
-      log(L_WARN "%s: Invalid rip_tag value %u for route %I/%d",
-	  p->p.name, rt_tag, net->n.prefix, net->n.pxlen);
+      log(L_WARN "%s: Invalid rip_tag value %u for route %N",
+	  p->p.name, rt_tag, net->n.addr);
       rt_metric = p->infinity;
       rt_tag = 0;
     }
@@ -355,7 +344,7 @@ rip_rt_notify(struct proto *P, struct rtable *table UNUSED, struct network *net,
      * collection.
      */
 
-    en = fib_get(&p->rtable, &net->n.prefix, net->n.pxlen);
+    en = fib_get(&p->rtable, net->n.addr);
 
     old_metric = en->valid ? en->metric : -1;
 
@@ -369,7 +358,7 @@ rip_rt_notify(struct proto *P, struct rtable *table UNUSED, struct network *net,
   else
   {
     /* Withdraw */
-    en = fib_find(&p->rtable, &net->n.prefix, net->n.pxlen);
+    en = fib_find(&p->rtable, net->n.addr);
 
     if (!en || en->valid != RIP_ENTRY_VALID)
       return;
@@ -875,7 +864,7 @@ rip_timer(timer *t)
 
       if (expires <= now)
       {
-	// TRACE(D_EVENTS, "entry is too old: %I/%d", en->n.prefix, en->n.pxlen);
+	// TRACE(D_EVENTS, "entry is too old: %N", en->n.addr);
 	en->valid = 0;
       }
       else
@@ -1108,7 +1097,8 @@ rip_start(struct proto *P)
   struct rip_config *cf = (void *) (P->cf);
 
   init_list(&p->iface_list);
-  fib_init(&p->rtable, P->pool, sizeof(struct rip_entry), 0, rip_init_entry);
+  fib_init(&p->rtable, P->pool, rip_is_v2(p) ? NET_IP4 : NET_IP6,
+	   sizeof(struct rip_entry), OFFSETOF(struct rip_entry, n), 0, NULL);
   p->rte_slab = sl_new(P->pool, sizeof(struct rip_rte));
   p->timer = tm_new_set(P->pool, rip_timer, p, 0, 0);
 
@@ -1257,8 +1247,8 @@ rip_dump(struct proto *P)
   FIB_WALK(&p->rtable, e)
   {
     struct rip_entry *en = (struct rip_entry *) e;
-    debug("RIP: entry #%d: %I/%d via %I dev %s valid %d metric %d age %d s\n",
-	  i++, en->n.prefix, en->n.pxlen, en->next_hop, en->iface->name,
+    debug("RIP: entry #%d: %N via %I dev %s valid %d metric %d age %d s\n",
+	  i++, en->n.addr, en->next_hop, en->iface->name,
 	  en->valid, en->metric, now - en->changed);
   }
   FIB_WALK_END;
diff --git a/proto/rip/rip.h b/proto/rip/rip.h
index f245e612..97c5ab3f 100644
--- a/proto/rip/rip.h
+++ b/proto/rip/rip.h
@@ -149,7 +149,6 @@ struct rip_neighbor
 
 struct rip_entry
 {
-  struct fib_node n;
   struct rip_rte *routes;		/* List of incoming routes */
 
   u8 valid;				/* Entry validity state (RIP_ENTRY_*) */
@@ -160,6 +159,8 @@ struct rip_entry
   ip_addr next_hop;			/* Outgoing route next hop */
 
   bird_clock_t changed;			/* Last time when the outgoing route metric changed */
+
+  struct fib_node n;
 };
 
 struct rip_rte
@@ -211,8 +212,8 @@ rip_reset_tx_session(struct rip_proto *p, struct rip_iface *ifa)
 }
 
 /* rip.c */
-void rip_update_rte(struct rip_proto *p, ip_addr *prefix, int pxlen, struct rip_rte *new);
-void rip_withdraw_rte(struct rip_proto *p, ip_addr *prefix, int pxlen, struct rip_neighbor *from);
+void rip_update_rte(struct rip_proto *p, net_addr *n, struct rip_rte *new);
+void rip_withdraw_rte(struct rip_proto *p, net_addr *n, struct rip_neighbor *from);
 struct rip_neighbor * rip_get_neighbor(struct rip_proto *p, ip_addr *a, struct rip_iface *ifa);
 void rip_update_bfd(struct rip_proto *p, struct rip_neighbor *n);
 void rip_show_interfaces(struct proto *P, char *iff);