A Protocol Independent Hierarchical FIB (VPP-352)

Main Enhancements:
 - Protocol Independent FIB API
 - Hierarchical FIB entries. Dynamic recursive route resolution.
 - Extranet Support.
 - Integration of IP and MPLS forwarding.
 - Separation of FIB and Adjacency databases.
 - Data-Plane Object forwarding model.

Change-Id: I52dc815c0d0aa8b493e3cf6b978568f3cc82296c
Signed-off-by: Neale Ranns <nranns@cisco.com>

1 files changed, 343 insertions, 0 deletions

diff --git a/vnet/vnet/mpls/mpls_output.c b/vnet/vnet/mpls/mpls_output.c
new file mode 100644
index 00000000000..932fcb8d0bd
--- /dev/null
+++ b/vnet/vnet/mpls/mpls_output.c
@@ -0,0 +1,343 @@
+/*
+ * mpls_output.c: MPLS Adj rewrite
+ *
+ * Copyright (c) 2012-2014 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 <vlib/vlib.h>
+#include <vnet/pg/pg.h>
+#include <vnet/mpls/mpls.h>
+
+typedef struct {
+  /* Adjacency taken. */
+  u32 adj_index;
+  u32 flow_hash;
+
+  /* Packet data, possibly *after* rewrite. */
+  u8 packet_data[64 - 1*sizeof(u32)];
+} mpls_output_trace_t;
+
+static u8 *
+format_mpls_output_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 *);
+  mpls_output_trace_t * t = va_arg (*args, mpls_output_trace_t *);
+  vnet_main_t * vnm = vnet_get_main();
+  uword indent = format_get_indent (s);
+
+  s = format (s, "adj-idx %d : %U flow hash: 0x%08x",
+              t->adj_index,
+              format_ip_adjacency, vnm, t->adj_index, FORMAT_IP_ADJACENCY_NONE,
+	      t->flow_hash);
+  s = format (s, "\n%U%U",
+              format_white_space, indent,
+              format_ip_adjacency_packet_data,
+              vnm, t->adj_index,
+              t->packet_data, sizeof (t->packet_data));
+  return s;
+}
+
+static inline uword
+mpls_output_inline (vlib_main_t * vm,
+                    vlib_node_runtime_t * node,
+                    vlib_frame_t * from_frame)
+{
+  u32 n_left_from, next_index, * from, * to_next, cpu_index;
+  vlib_node_runtime_t * error_node;
+
+  cpu_index = os_get_cpu_number();
+  error_node = vlib_node_get_runtime (vm, mpls_output_node.index);
+  from = vlib_frame_vector_args (from_frame);
+  n_left_from = from_frame->n_vectors;
+  next_index = node->cached_next_index;
+
+  while (n_left_from > 0)
+    {
+      u32 n_left_to_next;
+
+      vlib_get_next_frame (vm, node, next_index,
+                           to_next, n_left_to_next);
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+        {
+	  ip_adjacency_t * adj0;
+          mpls_unicast_header_t *hdr0;
+	  vlib_buffer_t * p0;
+	  u32 pi0, rw_len0, adj_index0, next0, error0;
+
+	  pi0 = to_next[0] = from[0];
+
+	  p0 = vlib_get_buffer (vm, pi0);
+
+	  adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
+
+          /* We should never rewrite a pkt using the MISS adjacency */
+          ASSERT(adj_index0);
+
+	  adj0 = adj_get(adj_index0);
+      	  hdr0 = vlib_buffer_get_current (p0);
+
+	  /* Guess we are only writing on simple Ethernet header. */
+          vnet_rewrite_one_header (adj0[0], hdr0, 
+                                   sizeof (ethernet_header_t));
+          
+          /* Update packet buffer attributes/set output interface. */
+          rw_len0 = adj0[0].rewrite_header.data_bytes;
+          
+          if (PREDICT_FALSE (rw_len0 > sizeof(ethernet_header_t)))
+              vlib_increment_combined_counter 
+                  (&adjacency_counters,
+                   cpu_index, adj_index0, 
+                   /* packet increment */ 0,
+                   /* byte increment */ rw_len0-sizeof(ethernet_header_t));
+          
+          /* Check MTU of outgoing interface. */
+          error0 = (vlib_buffer_length_in_chain (vm, p0) 
+                    > adj0[0].rewrite_header.max_l3_packet_bytes
+                    ? IP4_ERROR_MTU_EXCEEDED
+                    : IP4_ERROR_NONE);
+
+	  p0->error = error_node->errors[error0];
+
+          /* Don't adjust the buffer for ttl issue; icmp-error node wants
+           * to see the IP headerr */
+          if (PREDICT_TRUE(error0 == IP4_ERROR_NONE))
+            {
+              p0->current_data -= rw_len0;
+              p0->current_length += rw_len0;
+
+              vnet_buffer (p0)->sw_if_index[VLIB_TX] =
+                  adj0[0].rewrite_header.sw_if_index;
+              next0 = adj0[0].rewrite_header.next_index;
+            }
+          else
+            {
+              next0 = MPLS_OUTPUT_NEXT_DROP;
+            }
+
+	  from += 1;
+	  n_left_from -= 1;
+	  to_next += 1;
+	  n_left_to_next -= 1;
+      
+          if (PREDICT_FALSE(p0->flags & VLIB_BUFFER_IS_TRACED)) 
+            {
+              mpls_output_trace_t *tr = vlib_add_trace (vm, node, 
+                                                        p0, sizeof (*tr));
+              tr->adj_index = vnet_buffer(p0)->ip.adj_index[VLIB_TX];
+              tr->flow_hash = vnet_buffer(p0)->ip.flow_hash;
+            }
+
+	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
+					   to_next, n_left_to_next,
+					   pi0, next0);
+        }
+
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+  vlib_node_increment_counter (vm, mpls_output_node.index,
+                               MPLS_ERROR_PKTS_ENCAP,
+                               from_frame->n_vectors);
+
+  return from_frame->n_vectors;
+}
+
+static char * mpls_error_strings[] = {
+#define mpls_error(n,s) s,
+#include "error.def"
+#undef mpls_error
+};
+
+static inline uword
+mpls_output (vlib_main_t * vm,
+             vlib_node_runtime_t * node,
+             vlib_frame_t * from_frame)
+{
+    return (mpls_output_inline(vm, node, from_frame));
+}
+
+VLIB_REGISTER_NODE (mpls_output_node) = {
+  .function = mpls_output,
+  .name = "mpls-output",
+  /* Takes a vector of packets. */
+  .vector_size = sizeof (u32),
+  .n_errors = MPLS_N_ERROR,
+  .error_strings = mpls_error_strings,
+
+  .n_next_nodes = MPLS_OUTPUT_N_NEXT,
+  .next_nodes = {
+#define _(s,n) [MPLS_OUTPUT_NEXT_##s] = n,
+    foreach_mpls_output_next
+#undef _
+  },
+
+  .format_trace = format_mpls_output_trace,
+};
+
+VLIB_NODE_FUNCTION_MULTIARCH (mpls_output_node, mpls_output)
+
+static inline uword
+mpls_midchain (vlib_main_t * vm,
+               vlib_node_runtime_t * node,
+               vlib_frame_t * from_frame)
+{
+    return (mpls_output_inline(vm, node, from_frame));
+}
+
+VLIB_REGISTER_NODE (mpls_midchain_node) = {
+  .function = mpls_output,
+  .name = "mpls-midchain",
+  .vector_size = sizeof (u32),
+
+  .format_trace = format_mpls_output_trace,
+
+  .sibling_of = "mpls-output",
+};
+
+VLIB_NODE_FUNCTION_MULTIARCH (mpls_midchain_node, mpls_midchain)
+
+/**
+ * @brief Next index values from the MPLS incomplete adj node
+ */
+#define foreach_mpls_adj_incomplete_next       	\
+_(DROP, "error-drop")                   \
+_(IP4,  "ip4-arp")                      \
+_(IP6,  "ip6-discover-neighbor")
+
+typedef enum {
+#define _(s,n) MPLS_ADJ_INCOMPLETE_NEXT_##s,
+  foreach_mpls_adj_incomplete_next
+#undef _
+  MPLS_ADJ_INCOMPLETE_N_NEXT,
+} mpls_adj_incomplete_next_t;
+
+/**
+ * @brief A struct to hold tracing information for the MPLS label imposition
+ * node.
+ */
+typedef struct mpls_adj_incomplete_trace_t_
+{
+    u32 next;
+} mpls_adj_incomplete_trace_t;
+
+
+/**
+ * @brief Graph node for incomplete MPLS adjacency.
+ * This node will push traffic to either the v4-arp or v6-nd node
+ * based on the next-hop proto of the adj.
+ * We pay a cost for this 'routing' node, but an incomplete adj is the
+ * exception case.
+ */
+static inline uword
+mpls_adj_incomplete (vlib_main_t * vm,
+                     vlib_node_runtime_t * node,
+                     vlib_frame_t * from_frame)
+{
+    u32 n_left_from, next_index, * from, * to_next;
+
+  from = vlib_frame_vector_args (from_frame);
+  n_left_from = from_frame->n_vectors;
+  next_index = node->cached_next_index;
+
+  while (n_left_from > 0)
+    {
+      u32 n_left_to_next;
+
+      vlib_get_next_frame (vm, node, next_index,
+                           to_next, n_left_to_next);
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+        {
+          u32 pi0, next0, adj_index0;
+	  ip_adjacency_t * adj0;
+	  vlib_buffer_t * p0;
+
+ 	  pi0 = to_next[0] = from[0];
+	  p0 = vlib_get_buffer (vm, pi0);
+	  from += 1;
+	  n_left_from -= 1;
+	  to_next += 1;
+	  n_left_to_next -= 1;
+
+          adj_index0 = vnet_buffer (p0)->ip.adj_index[VLIB_TX];
+          ASSERT(adj_index0);
+
+	  adj0 = adj_get(adj_index0);
+
+          if (PREDICT_TRUE(FIB_PROTOCOL_IP4 == adj0->ia_nh_proto))
+          {
+              next0 = MPLS_ADJ_INCOMPLETE_NEXT_IP4;
+          }
+          else
+          {
+              next0 = MPLS_ADJ_INCOMPLETE_NEXT_IP6;
+          }              
+
+	  if (PREDICT_FALSE(p0->flags & VLIB_BUFFER_IS_TRACED)) 
+	  {
+	      mpls_adj_incomplete_trace_t *tr =
+		  vlib_add_trace (vm, node, p0, sizeof (*tr));
+	      tr->next = next0;
+	  }
+
+	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
+					   to_next, n_left_to_next,
+					   pi0, next0);
+        }
+
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  return from_frame->n_vectors;
+}
+
+static u8 *
+format_mpls_adj_incomplete_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 *);
+    mpls_adj_incomplete_trace_t * t;
+    uword indent;
+
+    t = va_arg (*args, mpls_adj_incomplete_trace_t *);
+    indent = format_get_indent (s);
+
+    s = format (s, "%Unext:%d",
+                format_white_space, indent,
+                t->next);
+    return (s);
+}
+
+VLIB_REGISTER_NODE (mpls_adj_incomplete_node) = {
+  .function = mpls_adj_incomplete,
+  .name = "mpls-adj-incomplete",
+  .format_trace = format_mpls_adj_incomplete_trace,
+  /* Takes a vector of packets. */
+  .vector_size = sizeof (u32),
+  .n_errors = MPLS_N_ERROR,
+  .error_strings = mpls_error_strings,
+
+  .n_next_nodes = MPLS_ADJ_INCOMPLETE_N_NEXT,
+  .next_nodes = {
+#define _(s,n) [MPLS_ADJ_INCOMPLETE_NEXT_##s] = n,
+    foreach_mpls_adj_incomplete_next
+#undef _
+  },
+
+  .format_trace = format_mpls_output_trace,
+};
+
+VLIB_NODE_FUNCTION_MULTIARCH (mpls_adj_incomplete_node,
+                              mpls_adj_incomplete)