IP-Punt-redirect: allow the use of a FIB path to describe how to

redirect

Change-Id: I2a3ba2a3d73ea8511e3a511855b041432328f0a8
Signed-off-by: Neale Ranns <nranns@cisco.com>

1 files changed, 251 insertions, 0 deletions

diff --git a/src/vnet/ip/ip_punt_drop.c b/src/vnet/ip/ip_punt_drop.c
new file mode 100644
index 00000000000..01577a472ce
--- /dev/null
+++ b/src/vnet/ip/ip_punt_drop.c
@@ -0,0 +1,251 @@
+/*
+ * Copyright (c) 2015 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <vnet/ip/ip.h>
+#include <vnet/ip/ip_punt_drop.h>
+#include <vnet/policer/policer.h>
+#include <vnet/policer/police_inlines.h>
+#include <vnet/fib/fib_path_list.h>
+
+ip_punt_redirect_cfg_t ip_punt_redirect_cfg;
+
+u8 *
+format_ip_punt_redirect_trace (u8 * s, va_list * args)
+{
+  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+  ip_punt_redirect_trace_t *t = va_arg (*args, ip_punt_redirect_trace_t *);
+
+  if (INDEX_INVALID == t->rrxi)
+    s = format (s, "drop");
+  else
+    s = format (s, "via redirect:%d", t->rrxi);
+
+  return s;
+}
+
+static void
+ip_punt_redirect_stack (ip_punt_redirect_rx_t * ipr)
+{
+  dpo_id_t dpo = DPO_INVALID;
+  vlib_node_t *pnode;
+
+  fib_path_list_contribute_forwarding (ipr->pl,
+				       ipr->payload_type,
+				       FIB_PATH_LIST_FWD_FLAG_COLLAPSE, &dpo);
+
+  if (FIB_PROTOCOL_IP4 == ipr->fproto)
+    pnode =
+      vlib_get_node_by_name (vlib_get_main (), (u8 *) "ip4-punt-redirect");
+  else
+    pnode =
+      vlib_get_node_by_name (vlib_get_main (), (u8 *) "ip6-punt-redirect");
+
+  dpo_stack_from_node (pnode->index, &ipr->dpo, &dpo);
+  dpo_reset (&dpo);
+}
+
+index_t
+ip_punt_redirect_find (fib_protocol_t fproto, u32 rx_sw_if_index)
+{
+  index_t *rxs;
+
+  rxs = ip_punt_redirect_cfg.redirect_by_rx_sw_if_index[fproto];
+
+  if (vec_len (rxs) <= rx_sw_if_index)
+    return (INDEX_INVALID);
+
+  return rxs[rx_sw_if_index];
+}
+
+void
+ip_punt_redirect_add (fib_protocol_t fproto,
+		      u32 rx_sw_if_index,
+		      fib_forward_chain_type_t ct, fib_route_path_t * rpaths)
+{
+  ip_punt_redirect_rx_t *ipr;
+  index_t ipri;
+
+  if (~0 == rx_sw_if_index)
+    rx_sw_if_index = 0;
+
+  vec_validate_init_empty (ip_punt_redirect_cfg.redirect_by_rx_sw_if_index
+			   [fproto], rx_sw_if_index, INDEX_INVALID);
+
+  pool_get (ip_punt_redirect_cfg.pool, ipr);
+  ipri = ipr - ip_punt_redirect_cfg.pool;
+
+  ip_punt_redirect_cfg.redirect_by_rx_sw_if_index[fproto][rx_sw_if_index] =
+    ipri;
+
+  fib_node_init (&ipr->node, FIB_NODE_TYPE_IP_PUNT_REDIRECT);
+  ipr->fproto = fproto;
+  ipr->payload_type = ct;
+
+  ipr->pl = fib_path_list_create (FIB_PATH_LIST_FLAG_NO_URPF, rpaths);
+
+  ipr->sibling = fib_path_list_child_add (ipr->pl,
+					  FIB_NODE_TYPE_IP_PUNT_REDIRECT,
+					  ipri);
+
+  ip_punt_redirect_stack (ipr);
+}
+
+void
+ip_punt_redirect_del (fib_protocol_t fproto, u32 rx_sw_if_index)
+{
+  ip_punt_redirect_rx_t *ipr;
+  index_t *rxs;
+
+  if (~0 == rx_sw_if_index)
+    rx_sw_if_index = 0;
+
+  rxs = ip_punt_redirect_cfg.redirect_by_rx_sw_if_index[fproto];
+
+  if ((vec_len (rxs) <= rx_sw_if_index) ||
+      (INDEX_INVALID == rxs[rx_sw_if_index]))
+    return;
+
+  ipr = ip_punt_redirect_get (rxs[rx_sw_if_index]);
+
+  fib_path_list_child_remove (ipr->pl, ipr->sibling);
+  dpo_reset (&ipr->dpo);
+  pool_put (ip_punt_redirect_cfg.pool, ipr);
+
+  rxs[rx_sw_if_index] = INDEX_INVALID;
+}
+
+u8 *
+format_ip_punt_redirect (u8 * s, va_list * args)
+{
+  fib_protocol_t fproto = va_arg (*args, int);
+  ip_punt_redirect_rx_t *rx;
+  index_t *rxs;
+  u32 rx_sw_if_index;
+  vnet_main_t *vnm = vnet_get_main ();
+
+  rxs = ip_punt_redirect_cfg.redirect_by_rx_sw_if_index[fproto];
+
+  vec_foreach_index (rx_sw_if_index, rxs)
+  {
+    if (INDEX_INVALID == rxs[rx_sw_if_index])
+      continue;
+
+    rx = ip_punt_redirect_get (rxs[rx_sw_if_index]);
+
+    s = format (s, " rx %U via:\n",
+		format_vnet_sw_interface_name, vnm,
+		vnet_get_sw_interface (vnm, rx_sw_if_index));
+    s = format (s, " %U", format_fib_path_list, rx->pl, 2);
+    s = format (s, " forwarding\n", format_dpo_id, &rx->dpo, 0);
+    s = format (s, "  %U\n", format_dpo_id, &rx->dpo, 0);
+  }
+
+  return (s);
+}
+
+void
+ip_punt_redirect_walk (fib_protocol_t fproto,
+		       ip_punt_redirect_walk_cb_t cb, void *ctx)
+{
+  ip_punt_redirect_rx_t *rx;
+  u32 ii, rx_sw_if_index;
+  index_t *rxs;
+
+  rxs = ip_punt_redirect_cfg.redirect_by_rx_sw_if_index[fproto];
+
+  vec_foreach_index (ii, rxs)
+  {
+    if (INDEX_INVALID == rxs[ii])
+      continue;
+
+    rx = ip_punt_redirect_get (rxs[ii]);
+
+    rx_sw_if_index = (ii == 0 ? ~0 : ii);
+    cb (rx_sw_if_index, rx, ctx);
+  }
+}
+
+static fib_node_t *
+ip_punt_redirect_get_node (fib_node_index_t index)
+{
+  ip_punt_redirect_rx_t *ipr = ip_punt_redirect_get (index);
+  return (&(ipr->node));
+}
+
+static ip_punt_redirect_rx_t *
+ip_punt_redirect_get_from_node (fib_node_t * node)
+{
+  return ((ip_punt_redirect_rx_t *) (((char *) node) -
+				     STRUCT_OFFSET_OF (ip_punt_redirect_rx_t,
+						       node)));
+}
+
+static void
+ip_punt_redirect_last_lock_gone (fib_node_t * node)
+{
+  /*
+   * the lifetime of the entry is managed by the table.
+   */
+  ASSERT (0);
+}
+
+/*
+ * A back walk has reached this BIER entry
+ */
+static fib_node_back_walk_rc_t
+ip_punt_redirect_back_walk_notify (fib_node_t * node,
+				   fib_node_back_walk_ctx_t * ctx)
+{
+  /*
+   * re-populate the ECMP tables with new choices
+   */
+  ip_punt_redirect_rx_t *ipr = ip_punt_redirect_get_from_node (node);
+
+  ip_punt_redirect_stack (ipr);
+
+  /*
+   * no need to propagate further up the graph, since there's nothing there
+   */
+  return (FIB_NODE_BACK_WALK_CONTINUE);
+}
+
+/*
+ * The BIER fmask's graph node virtual function table
+ */
+static const fib_node_vft_t ip_punt_redirect_vft = {
+  .fnv_get = ip_punt_redirect_get_node,
+  .fnv_last_lock = ip_punt_redirect_last_lock_gone,
+  .fnv_back_walk = ip_punt_redirect_back_walk_notify,
+};
+
+static clib_error_t *
+ip_punt_drop_init (vlib_main_t * vm)
+{
+  fib_node_register_type (FIB_NODE_TYPE_IP_PUNT_REDIRECT,
+			  &ip_punt_redirect_vft);
+
+  return (NULL);
+}
+
+VLIB_INIT_FUNCTION (ip_punt_drop_init);
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */