zebra: Create zebra_static.[ch] to isolate code

Isolate the zebra static_XXX functions from zebra_rib.c
This is the first in a series of changes to clean up
the zebra code a bit more.

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>

1 files changed, 617 insertions, 0 deletions

diff --git a/zebra/zebra_static.c b/zebra/zebra_static.c
new file mode 100644
index 000000000..9d16f1267
--- /dev/null
+++ b/zebra/zebra_static.c
@@ -0,0 +1,617 @@
+/*
+ * Static Routing Information code
+ * Copyright (C) 2016 Cumulus Networks
+ *               Donald Sharp
+ *
+ * This file is part of Quagga.
+ *
+ * Quagga is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * Quagga is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Quagga; see the file COPYING.  If not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+#include <zebra.h>
+
+#include <lib/nexthop.h>
+#include <lib/memory.h>
+
+#include "zebra/debug.h"
+#include "zebra/rib.h"
+#include "zebra/zserv.h"
+#include "zebra/zebra_vrf.h"
+#include "zebra/zebra_static.h"
+#include "zebra/zebra_rnh.h"
+#include "zebra/redistribute.h"
+
+/* Install static route into rib. */
+void
+static_install_route (afi_t afi, safi_t safi, struct prefix *p, struct static_route *si)
+{
+  struct rib *rib;
+  struct route_node *rn;
+  struct route_table *table;
+  struct prefix nh_p;
+
+  /* Lookup table.  */
+  table = zebra_vrf_table (afi, safi, si->vrf_id);
+  if (! table)
+    return;
+
+  /* Lookup existing route */
+  rn = route_node_get (table, p);
+  RNODE_FOREACH_RIB (rn, rib)
+    {
+       if (CHECK_FLAG (rib->status, RIB_ENTRY_REMOVED))
+         continue;
+
+       if (rib->type == ZEBRA_ROUTE_STATIC && rib->distance == si->distance)
+         break;
+    }
+
+  if (rib)
+    {
+      /* if tag value changed , update old value in RIB */
+      if (rib->tag != si->tag)
+        rib->tag = si->tag;
+
+      /* Same distance static route is there.  Update it with new
+         nexthop. */
+      route_unlock_node (rn);
+      switch (si->type)
+        {
+	case STATIC_IPV4_GATEWAY:
+	  rib_nexthop_ipv4_add (rib, &si->addr.ipv4, NULL);
+	  nh_p.family = AF_INET;
+	  nh_p.prefixlen = IPV4_MAX_BITLEN;
+	  nh_p.u.prefix4 = si->addr.ipv4;
+	  zebra_register_rnh_static_nh(si->vrf_id, &nh_p, rn);
+	  break;
+	case STATIC_IFINDEX:
+	  rib_nexthop_ifindex_add (rib, si->ifindex);
+	  break;
+	case STATIC_IPV4_BLACKHOLE:
+	  rib_nexthop_blackhole_add (rib);
+	  break;
+	case STATIC_IPV6_GATEWAY:
+	  rib_nexthop_ipv6_add (rib, &si->addr.ipv6);
+	  nh_p.family = AF_INET6;
+	  nh_p.prefixlen = IPV6_MAX_BITLEN;
+	  nh_p.u.prefix6 = si->addr.ipv6;
+	  zebra_register_rnh_static_nh(si->vrf_id, &nh_p, rn);
+	  break;
+	case STATIC_IPV6_GATEWAY_IFINDEX:
+	  rib_nexthop_ipv6_ifindex_add (rib, &si->addr.ipv6, si->ifindex);
+	  break;
+        }
+
+      if (IS_ZEBRA_DEBUG_RIB)
+        {
+          char buf[INET6_ADDRSTRLEN];
+          if (IS_ZEBRA_DEBUG_RIB)
+            {
+              inet_ntop (p->family, &p->u.prefix, buf, INET6_ADDRSTRLEN);
+              zlog_debug ("%u:%s/%d: Modifying route rn %p, rib %p (type %d)",
+                          si->vrf_id, buf, p->prefixlen, rn, rib, rib->type);
+            }
+        }
+      /* Schedule route for processing or invoke NHT, as appropriate. */
+      if (si->type == STATIC_IPV4_GATEWAY ||
+          si->type == STATIC_IPV6_GATEWAY)
+        zebra_evaluate_rnh(si->vrf_id, nh_p.family, 1, RNH_NEXTHOP_TYPE, &nh_p);
+      else
+        rib_queue_add (rn);
+    }
+  else
+    {
+      /* This is new static route. */
+      rib = XCALLOC (MTYPE_RIB, sizeof (struct rib));
+
+      rib->type = ZEBRA_ROUTE_STATIC;
+      rib->instance = 0;
+      rib->distance = si->distance;
+      rib->metric = 0;
+      rib->mtu = 0;
+      rib->vrf_id = si->vrf_id;
+      rib->table =  si->vrf_id ? (zebra_vrf_lookup(si->vrf_id))->table_id : zebrad.rtm_table_default;
+      rib->nexthop_num = 0;
+      rib->tag = si->tag;
+
+      switch (si->type)
+        {
+	case STATIC_IPV4_GATEWAY:
+	  rib_nexthop_ipv4_add (rib, &si->addr.ipv4, NULL);
+	  nh_p.family = AF_INET;
+	  nh_p.prefixlen = IPV4_MAX_BITLEN;
+	  nh_p.u.prefix4 = si->addr.ipv4;
+	  zebra_register_rnh_static_nh(si->vrf_id, &nh_p, rn);
+	  break;
+	case STATIC_IFINDEX:
+	  rib_nexthop_ifindex_add (rib, si->ifindex);
+	  break;
+	case STATIC_IPV4_BLACKHOLE:
+	  rib_nexthop_blackhole_add (rib);
+	  break;
+	case STATIC_IPV6_GATEWAY:
+	  rib_nexthop_ipv6_add (rib, &si->addr.ipv6);
+	  nh_p.family = AF_INET6;
+	  nh_p.prefixlen = IPV6_MAX_BITLEN;
+	  nh_p.u.prefix6 = si->addr.ipv6;
+	  zebra_register_rnh_static_nh(si->vrf_id, &nh_p, rn);
+	  break;
+	case STATIC_IPV6_GATEWAY_IFINDEX:
+	  rib_nexthop_ipv6_ifindex_add (rib, &si->addr.ipv6, si->ifindex);
+	  break;
+        }
+
+      /* Save the flags of this static routes (reject, blackhole) */
+      rib->flags = si->flags;
+
+      if (IS_ZEBRA_DEBUG_RIB)
+        {
+          char buf[INET6_ADDRSTRLEN];
+          if (IS_ZEBRA_DEBUG_RIB)
+            {
+              inet_ntop (p->family, &p->u.prefix, buf, INET6_ADDRSTRLEN);
+              zlog_debug ("%u:%s/%d: Inserting route rn %p, rib %p (type %d)",
+                          si->vrf_id, buf, p->prefixlen, rn, rib, rib->type);
+            }
+        }
+      /* Link this rib to the tree. Schedule for processing or invoke NHT,
+       * as appropriate.
+       */
+      if (si->type == STATIC_IPV4_GATEWAY ||
+          si->type == STATIC_IPV6_GATEWAY)
+        {
+          rib_addnode (rn, rib, 0);
+          zebra_evaluate_rnh(si->vrf_id, nh_p.family, 1, RNH_NEXTHOP_TYPE, &nh_p);
+        }
+      else
+        rib_addnode (rn, rib, 1);
+    }
+}
+static int
+static_nexthop_same (struct nexthop *nexthop, struct static_route *si)
+{
+  if (nexthop->type == NEXTHOP_TYPE_IPV4
+      && si->type == STATIC_IPV4_GATEWAY
+      && IPV4_ADDR_SAME (&nexthop->gate.ipv4, &si->addr.ipv4))
+    return 1;
+  if (nexthop->type == NEXTHOP_TYPE_IFINDEX
+      && si->type == STATIC_IFINDEX
+      && nexthop->ifindex == si->ifindex)
+    return 1;
+  if (nexthop->type == NEXTHOP_TYPE_BLACKHOLE
+      && si->type == STATIC_IPV4_BLACKHOLE)
+    return 1;
+  if (nexthop->type == NEXTHOP_TYPE_IPV6
+      && si->type == STATIC_IPV6_GATEWAY
+      && IPV6_ADDR_SAME (&nexthop->gate.ipv6, &si->addr.ipv6))
+    return 1;
+  if (nexthop->type == NEXTHOP_TYPE_IPV6_IFINDEX
+      && si->type == STATIC_IPV6_GATEWAY_IFINDEX
+      && IPV6_ADDR_SAME (&nexthop->gate.ipv6, &si->addr.ipv6)
+      && nexthop->ifindex == si->ifindex)
+    return 1;
+  return 0;
+}
+
+/* Uninstall static route from RIB. */
+void
+static_uninstall_route (afi_t afi, safi_t safi, struct prefix *p, struct static_route *si)
+{
+  struct route_node *rn;
+  struct rib *rib;
+  struct nexthop *nexthop;
+  struct route_table *table;
+  struct prefix nh_p;
+
+  /* Lookup table.  */
+  table = zebra_vrf_table (afi, safi, si->vrf_id);
+  if (! table)
+    return;
+
+  /* Lookup existing route with type and distance. */
+  rn = route_node_lookup (table, p);
+  if (! rn)
+    return;
+
+  RNODE_FOREACH_RIB (rn, rib)
+    {
+      if (CHECK_FLAG (rib->status, RIB_ENTRY_REMOVED))
+        continue;
+
+      if (rib->type == ZEBRA_ROUTE_STATIC && rib->distance == si->distance &&
+          rib->tag == si->tag)
+        break;
+    }
+
+  if (! rib)
+    {
+      route_unlock_node (rn);
+      return;
+    }
+
+  /* Lookup nexthop. */
+  for (nexthop = rib->nexthop; nexthop; nexthop = nexthop->next)
+    if (static_nexthop_same (nexthop, si))
+      break;
+
+  /* Can't find nexthop. */
+  if (! nexthop)
+    {
+      route_unlock_node (rn);
+      return;
+    }
+
+  /* Check nexthop. */
+  if (rib->nexthop_num == 1)
+    rib_delnode (rn, rib);
+  else
+    {
+      /* Mark this nexthop as inactive and reinstall the route. Then, delete
+       * the nexthop. There is no need to re-evaluate the route for this
+       * scenario.
+       */
+      if (IS_ZEBRA_DEBUG_RIB)
+        {
+          char buf[INET6_ADDRSTRLEN];
+          if (IS_ZEBRA_DEBUG_RIB)
+            {
+              inet_ntop (p->family, &p->u.prefix, buf, INET6_ADDRSTRLEN);
+              zlog_debug ("%u:%s/%d: Modifying route rn %p, rib %p (type %d)",
+                          si->vrf_id, buf, p->prefixlen, rn, rib, rib->type);
+            }
+        }
+      UNSET_FLAG(nexthop->flags, NEXTHOP_FLAG_ACTIVE);
+      if (CHECK_FLAG (nexthop->flags, NEXTHOP_FLAG_FIB))
+        {
+          /* If there are other active nexthops, do an update. */
+          if (rib->nexthop_active_num > 1)
+            {
+              rib_install_kernel (rn, rib, 1);
+              redistribute_update (&rn->p, rib, NULL);
+            }
+          else
+            {
+              redistribute_delete (&rn->p, rib);
+              rib_uninstall_kernel (rn, rib);
+            }
+        }
+
+      if (afi == AFI_IP)
+	{
+	  /* Delete the nexthop and dereg from NHT */
+	  nh_p.family = AF_INET;
+	  nh_p.prefixlen = IPV4_MAX_BITLEN;
+	  nh_p.u.prefix4 = nexthop->gate.ipv4;
+	}
+      else
+	{
+	  nh_p.family = AF_INET6;
+	  nh_p.prefixlen = IPV6_MAX_BITLEN;
+	  nh_p.u.prefix6 = nexthop->gate.ipv6;
+	}
+      rib_nexthop_delete (rib, nexthop);
+      zebra_deregister_rnh_static_nh(si->vrf_id, &nh_p, rn);
+      nexthop_free (nexthop);
+    }
+  /* Unlock node. */
+  route_unlock_node (rn);
+}
+
+int
+static_add_ipv4 (safi_t safi, struct prefix *p, struct in_addr *gate, ifindex_t ifindex,
+		 const char *ifname, u_char flags, u_short tag,
+		 u_char distance, struct zebra_vrf *zvrf)
+{
+  u_char type = 0;
+  struct route_node *rn;
+  struct static_route *si;
+  struct static_route *pp;
+  struct static_route *cp;
+  struct static_route *update = NULL;
+  struct route_table *stable = zvrf->stable[AFI_IP][safi];
+
+  if (! stable)
+    return -1;
+
+  /* Lookup static route prefix. */
+  rn = route_node_get (stable, p);
+
+  /* Make flags. */
+  if (gate)
+    type = STATIC_IPV4_GATEWAY;
+  else if (ifindex)
+    type = STATIC_IFINDEX;
+  else
+    type = STATIC_IPV4_BLACKHOLE;
+
+  /* Do nothing if there is a same static route.  */
+  for (si = rn->info; si; si = si->next)
+    {
+      if (type == si->type
+	  && (! gate || IPV4_ADDR_SAME (gate, &si->addr.ipv4))
+	  && (! ifindex || ifindex == si->ifindex))
+	{
+	  if ((distance == si->distance) && (tag == si->tag))
+	    {
+	      route_unlock_node (rn);
+	      return 0;
+	    }
+	  else
+	    update = si;
+	}
+    }
+
+  /* Distance or tag changed. */
+  if (update)
+    static_delete_ipv4 (safi, p, gate, ifindex, update->tag, update->distance, zvrf);
+
+  /* Make new static route structure. */
+  si = XCALLOC (MTYPE_STATIC_ROUTE, sizeof (struct static_route));
+
+  si->type = type;
+  si->distance = distance;
+  si->flags = flags;
+  si->tag = tag;
+  si->vrf_id = zvrf->vrf_id;
+  si->ifindex = ifindex;
+  if (si->ifindex)
+    strcpy(si->ifname, ifname);
+
+  if (gate)
+    si->addr.ipv4 = *gate;
+
+  /* Add new static route information to the tree with sort by
+     distance value and gateway address. */
+  for (pp = NULL, cp = rn->info; cp; pp = cp, cp = cp->next)
+    {
+      if (si->distance < cp->distance)
+	break;
+      if (si->distance > cp->distance)
+	continue;
+      if (si->type == STATIC_IPV4_GATEWAY && cp->type == STATIC_IPV4_GATEWAY)
+	{
+	  if (ntohl (si->addr.ipv4.s_addr) < ntohl (cp->addr.ipv4.s_addr))
+	    break;
+	  if (ntohl (si->addr.ipv4.s_addr) > ntohl (cp->addr.ipv4.s_addr))
+	    continue;
+	}
+    }
+
+  /* Make linked list. */
+  if (pp)
+    pp->next = si;
+  else
+    rn->info = si;
+  if (cp)
+    cp->prev = si;
+  si->prev = pp;
+  si->next = cp;
+
+  /* Install into rib. */
+  static_install_route (AFI_IP, safi, p, si);
+
+  return 1;
+}
+
+int
+static_delete_ipv4 (safi_t safi, struct prefix *p, struct in_addr *gate, ifindex_t ifindex,
+		    u_short tag, u_char distance, struct zebra_vrf *zvrf)
+{
+  u_char type = 0;
+  struct route_node *rn;
+  struct static_route *si;
+  struct route_table *stable;
+
+  /* Lookup table.  */
+  stable = zebra_vrf_static_table (AFI_IP, safi, zvrf);
+  if (! stable)
+    return -1;
+
+  /* Lookup static route prefix. */
+  rn = route_node_lookup (stable, p);
+  if (! rn)
+    return 0;
+
+  /* Make flags. */
+  if (gate)
+    type = STATIC_IPV4_GATEWAY;
+  else if (ifindex)
+    type = STATIC_IFINDEX;
+  else
+    type = STATIC_IPV4_BLACKHOLE;
+
+  /* Find same static route is the tree */
+  for (si = rn->info; si; si = si->next)
+    if (type == si->type
+	&& (! gate || IPV4_ADDR_SAME (gate, &si->addr.ipv4))
+	&& (! ifindex || ifindex == si->ifindex)
+	&& (! tag || (tag == si->tag)))
+      break;
+
+  /* Can't find static route. */
+  if (! si)
+    {
+      route_unlock_node (rn);
+      return 0;
+    }
+
+  /* Install into rib. */
+  static_uninstall_route (AFI_IP, safi, p, si);
+
+  /* Unlink static route from linked list. */
+  if (si->prev)
+    si->prev->next = si->next;
+  else
+    rn->info = si->next;
+  if (si->next)
+    si->next->prev = si->prev;
+  route_unlock_node (rn);
+
+  /* Free static route configuration. */
+  XFREE (MTYPE_STATIC_ROUTE, si);
+
+  route_unlock_node (rn);
+
+  return 1;
+}
+
+/* Add static route into static route configuration. */
+int
+static_add_ipv6 (struct prefix *p, u_char type, struct in6_addr *gate,
+		 ifindex_t ifindex, const char *ifname, u_char flags,
+		 u_short tag, u_char distance, struct zebra_vrf *zvrf)
+{
+  struct route_node *rn;
+  struct static_route *si;
+  struct static_route *pp;
+  struct static_route *cp;
+  struct static_route *update = NULL;
+  struct route_table *stable = zvrf->stable[AFI_IP6][SAFI_UNICAST];
+
+  if (! stable)
+    return -1;
+
+  if (!gate &&
+      (type == STATIC_IPV6_GATEWAY || type == STATIC_IPV6_GATEWAY_IFINDEX))
+    return -1;
+
+  if (!ifindex &&
+      (type == STATIC_IPV6_GATEWAY_IFINDEX || type == STATIC_IFINDEX))
+    return -1;
+
+  /* Lookup static route prefix. */
+  rn = route_node_get (stable, p);
+
+  /* Do nothing if there is a same static route.  */
+  for (si = rn->info; si; si = si->next)
+    {
+      if (type == si->type
+	  && (! gate || IPV6_ADDR_SAME (gate, &si->addr.ipv6))
+	  && (! ifindex || ifindex ==  si->ifindex))
+	{
+	  if ((distance == si->distance) && (tag == si->tag))
+	    {
+	      route_unlock_node (rn);
+	      return 0;
+	    }
+	  else
+	    update = si;
+	}
+    }
+
+  /* Distance or tag changed. */
+  if (update)
+    static_delete_ipv6 (p, type, gate, ifindex, update->tag, update->distance, zvrf);
+
+  /* Make new static route structure. */
+  si = XCALLOC (MTYPE_STATIC_ROUTE, sizeof (struct static_route));
+
+  si->type = type;
+  si->distance = distance;
+  si->flags = flags;
+  si->tag = tag;
+  si->vrf_id = zvrf->vrf_id;
+  si->ifindex = ifindex;
+  if (si->ifindex)
+    strcpy (si->ifname, ifname);
+
+  switch (type)
+    {
+    case STATIC_IPV6_GATEWAY:
+      si->addr.ipv6 = *gate;
+      break;
+    case STATIC_IPV6_GATEWAY_IFINDEX:
+      si->addr.ipv6 = *gate;
+      break;
+    }
+
+  /* Add new static route information to the tree with sort by
+     distance value and gateway address. */
+  for (pp = NULL, cp = rn->info; cp; pp = cp, cp = cp->next)
+    {
+      if (si->distance < cp->distance)
+	break;
+      if (si->distance > cp->distance)
+	continue;
+    }
+
+  /* Make linked list. */
+  if (pp)
+    pp->next = si;
+  else
+    rn->info = si;
+  if (cp)
+    cp->prev = si;
+  si->prev = pp;
+  si->next = cp;
+
+  /* Install into rib. */
+  static_install_route (AFI_IP6, SAFI_UNICAST, p, si);
+
+  return 1;
+}
+
+/* Delete static route from static route configuration. */
+int
+static_delete_ipv6 (struct prefix *p, u_char type, struct in6_addr *gate,
+		    ifindex_t ifindex, u_short tag, u_char distance,
+                    struct zebra_vrf *zvrf)
+{
+  struct route_node *rn;
+  struct static_route *si;
+  struct route_table *stable;
+
+  /* Lookup table.  */
+  stable = zebra_vrf_static_table (AFI_IP6, SAFI_UNICAST, zvrf);
+  if (! stable)
+    return -1;
+
+  /* Lookup static route prefix. */
+  rn = route_node_lookup (stable, p);
+  if (! rn)
+    return 0;
+
+  /* Find same static route is the tree */
+  for (si = rn->info; si; si = si->next)
+    if (distance == si->distance
+	&& type == si->type
+	&& (! gate || IPV6_ADDR_SAME (gate, &si->addr.ipv6))
+	&& (! ifindex || ifindex == si->ifindex)
+	&& (! tag || (tag == si->tag)))
+      break;
+
+  /* Can't find static route. */
+  if (! si)
+    {
+      route_unlock_node (rn);
+      return 0;
+    }
+
+  /* Install into rib. */
+  static_uninstall_route (AFI_IP6, SAFI_UNICAST, p, si);
+
+  /* Unlink static route from linked list. */
+  if (si->prev)
+    si->prev->next = si->next;
+  else
+    rn->info = si->next;
+  if (si->next)
+    si->next->prev = si->prev;
+
+  /* Free static route configuration. */
+  XFREE (MTYPE_STATIC_ROUTE, si);
+
+  return 1;
+}