Punt Infra

A punt/exception path that provides:
 1) clients that use the infra
 2) clients can create punt reasons
 3) clients can register to recieve packets that are punted
    for a given reason to be sent to the desired node.
 4) nodes which punt packets fill in the {reason,protocol} of the
    buffere (in the meta-data) and send to the new node "punt-dispatch"
 5) punt-dispatch sends packets to the registered nodes or drops

Change-Id: Ia4f144337f1387cbe585b4f375d0842aefffcde5
Signed-off-by: Neale Ranns <nranns@cisco.com>

2 files changed, 403 insertions, 0 deletions

diff --git a/src/plugins/unittest/CMakeLists.txt b/src/plugins/unittest/CMakeLists.txt
index 74bcef3c208..0af0dea250c 100644
--- a/src/plugins/unittest/CMakeLists.txt
+++ b/src/plugins/unittest/CMakeLists.txt
@@ -24,6 +24,7 @@ add_vpp_plugin(unittest
   ipsec_test.c
   interface_test.c
   mfib_test.c
+  punt_test.c
   session_test.c
   string_test.c
   tcp_test.c
diff --git a/src/plugins/unittest/punt_test.c b/src/plugins/unittest/punt_test.c
new file mode 100644
index 00000000000..3806dae88a3
--- /dev/null
+++ b/src/plugins/unittest/punt_test.c
@@ -0,0 +1,402 @@
+/*
+ * Copyright (c) 2018 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/vnet.h>
+#include <vnet/adj/rewrite.h>
+#include <vnet/ethernet/ethernet.h>
+#include <vnet/adj/adj.h>
+#include <vnet/ip/ip.h>
+
+typedef enum punt_next_t_
+{
+  PUNT_NEXT_DROP,
+  PUNT_N_NEXT,
+} punt_next_t;
+
+typedef struct punt_trace_t_
+{
+  vlib_punt_reason_t pt_reason;
+} punt_trace_t;
+
+/**
+ * Per-thread clone vectors
+ */
+u32 **punt_clones;
+
+#define SW_IF_INDEX_PG0 1
+#define SW_IF_INDEX_PG1 2
+
+index_t *adjs[FIB_PROTOCOL_IP_MAX];
+
+static vlib_punt_reason_t punt_reason_v4, punt_reason_v6;
+static vlib_punt_hdl_t punt_hdl;
+
+static u8 *
+format_punt_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 *);
+  punt_trace_t *t = va_arg (*args, punt_trace_t *);
+
+  s = format (s, "punt: %U", format_vlib_punt_reason, t->pt_reason);
+
+  return s;
+}
+
+always_inline uword
+punt_test_fwd (vlib_main_t * vm,
+	       vlib_node_runtime_t * node,
+	       vlib_frame_t * frame, fib_protocol_t fproto, u32 sw_if_index)
+{
+  u32 n_left_from, *from, *to_next, next_index;
+
+  from = vlib_frame_vector_args (frame);
+  n_left_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;
+	  vlib_buffer_t *b0;
+	  void *ip0;
+	  index_t ai0;
+	  u32 bi0;
+
+	  bi0 = to_next[0] = from[0];
+	  from += 1;
+	  to_next += 1;
+	  n_left_to_next -= 1;
+	  n_left_from -= 1;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+	  vnet_buffer (b0)->sw_if_index[VLIB_TX] = sw_if_index;
+	  ai0 = adjs[fproto][sw_if_index];
+
+	  adj0 = adj_get (ai0);
+	  ip0 = vlib_buffer_get_current (b0);
+
+	  vlib_buffer_advance (b0, -adj0->rewrite_header.data_bytes);
+	  vnet_rewrite_one_header (adj0[0], ip0, sizeof (ethernet_header_t));
+
+	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
+					   to_next, n_left_to_next, bi0, 0);
+	}
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  return frame->n_vectors;
+}
+
+always_inline uword
+punt_test_pg0_ip4 (vlib_main_t * vm,
+		   vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  return (punt_test_fwd (vm, node, frame, FIB_PROTOCOL_IP4, SW_IF_INDEX_PG0));
+}
+
+always_inline uword
+punt_test_pg1_ip4 (vlib_main_t * vm,
+		   vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  return (punt_test_fwd (vm, node, frame, FIB_PROTOCOL_IP4, SW_IF_INDEX_PG1));
+}
+
+always_inline uword
+punt_test_pg0_ip6 (vlib_main_t * vm,
+		   vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  return (punt_test_fwd (vm, node, frame, FIB_PROTOCOL_IP6, SW_IF_INDEX_PG0));
+}
+
+always_inline uword
+punt_test_pg1_ip6 (vlib_main_t * vm,
+		   vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  return (punt_test_fwd (vm, node, frame, FIB_PROTOCOL_IP6, SW_IF_INDEX_PG1));
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (punt_test_pg0_ip4_node) = {
+  .function = punt_test_pg0_ip4,
+  .name = "punt-test-pg0-ip4",
+  .vector_size = sizeof (u32),
+  .format_trace = format_punt_trace,
+};
+VLIB_REGISTER_NODE (punt_test_pg1_ip4_node) = {
+  .function = punt_test_pg1_ip4,
+  .name = "punt-test-pg1-ip4",
+  .vector_size = sizeof (u32),
+  .format_trace = format_punt_trace,
+};
+VLIB_REGISTER_NODE (punt_test_pg0_ip6_node) = {
+  .function = punt_test_pg0_ip6,
+  .name = "punt-test-pg0-ip6",
+  .vector_size = sizeof (u32),
+  .format_trace = format_punt_trace,
+};
+VLIB_REGISTER_NODE (punt_test_pg1_ip6_node) = {
+  .function = punt_test_pg1_ip6,
+  .name = "punt-test-pg1-ip6",
+  .vector_size = sizeof (u32),
+  .format_trace = format_punt_trace,
+};
+/* *INDENT-ON* */
+
+typedef struct punt_feat_trace_t_
+{
+  vlib_punt_reason_t pt_reason;
+} punt_feat_trace_t;
+
+always_inline uword
+punt_test_feat_inline (vlib_main_t * vm,
+		       vlib_node_runtime_t * node,
+		       vlib_frame_t * frame, u8 is_ip4)
+{
+  u32 n_left_from, *from, *to_next, next_index;
+
+  from = vlib_frame_vector_args (frame);
+  n_left_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)
+	{
+	  vlib_buffer_t *b0;
+	  u32 bi0, next0;
+
+	  bi0 = to_next[0] = from[0];
+	  from += 1;
+	  to_next += 1;
+	  n_left_to_next -= 1;
+	  n_left_from -= 1;
+	  next0 = 0;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+
+	  if (is_ip4)
+	    b0->punt_reason = punt_reason_v4;
+	  else
+	    b0->punt_reason = punt_reason_v6;
+
+	  if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
+	    {
+	      punt_feat_trace_t *t;
+
+	      b0 = vlib_get_buffer (vm, bi0);
+
+	      t = vlib_add_trace (vm, node, b0, sizeof (*t));
+	      t->pt_reason = b0->punt_reason;
+	    }
+	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
+					   to_next, n_left_to_next,
+					   bi0, next0);
+	}
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  return frame->n_vectors;
+}
+
+static u8 *
+format_punt_feat_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 *);
+  punt_feat_trace_t *t = va_arg (*args, punt_feat_trace_t *);
+
+  s = format (s, "reason: %U", format_vlib_punt_reason, t->pt_reason);
+
+  return s;
+}
+
+always_inline uword
+punt_test_feat_ip4 (vlib_main_t * vm,
+		    vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  return (punt_test_feat_inline (vm, node, frame, 1));
+}
+
+always_inline uword
+punt_test_feat_ip6 (vlib_main_t * vm,
+		    vlib_node_runtime_t * node, vlib_frame_t * frame)
+{
+  return (punt_test_feat_inline (vm, node, frame, 0));
+}
+
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE (punt_test_feat_ip6_node) = {
+  .function = punt_test_feat_ip6,
+  .name = "punt-test-feat-ip6",
+  .vector_size = sizeof (u32),
+  .format_trace = format_punt_feat_trace,
+  .n_next_nodes = 1,
+  .next_nodes = {
+    [0] = "punt-dispatch"
+  }
+};
+VLIB_REGISTER_NODE (punt_test_feat_ip4_node) = {
+  .function = punt_test_feat_ip4,
+  .name = "punt-test-feat-ip4",
+  .vector_size = sizeof (u32),
+  .format_trace = format_punt_feat_trace,
+  .n_next_nodes = 1,
+  .next_nodes = {
+    [0] = "punt-dispatch"
+  }
+};
+VNET_FEATURE_INIT (punt_test_feat_ip6_feature, static) =
+{
+  .arc_name = "ip6-unicast",
+  .node_name = "punt-test-feat-ip6",
+};
+VNET_FEATURE_INIT (punt_test_feat_ip4_feature, static) =
+{
+  .arc_name = "ip4-unicast",
+  .node_name = "punt-test-feat-ip4",
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+punt_test (vlib_main_t * vm,
+	   unformat_input_t * input, vlib_cli_command_t * cmd_arg)
+{
+  ip46_address_t ip46 = ip46_address_initializer;
+  fib_protocol_t fproto;
+  vnet_main_t *vnm;
+  u32 sw_if_index;
+  int rc;
+
+  vnm = vnet_get_main ();
+  fproto = FIB_PROTOCOL_IP4;
+
+  if (unformat (input, "%U", unformat_vnet_sw_interface, vnm, &sw_if_index))
+    {
+      vlib_node_t *from;
+
+      if (unformat (input, "%U", unformat_ip4_address, &ip46.ip4))
+	{
+	  fproto = FIB_PROTOCOL_IP4;
+	}
+      else if (unformat (input, "%U", unformat_ip6_address, &ip46.ip6))
+	{
+	  fproto = FIB_PROTOCOL_IP6;
+	}
+      else if (unformat (input, "clear"))
+	{
+	  vnet_feature_enable_disable ("ip4-unicast",
+				       "punt-test-feat-ip4",
+				       sw_if_index, 0, NULL, 0);
+	  vnet_feature_enable_disable ("ip6-unicast",
+				       "punt-test-feat-ip6",
+				       sw_if_index, 0, NULL, 0);
+	  return NULL;
+	}
+      else
+	{
+	  /*
+	   * allocate a client and a reason
+	   */
+	  punt_hdl = vlib_punt_client_register ("test");
+
+	  rc =
+	    vlib_punt_reason_alloc (punt_hdl, "reason-v4", &punt_reason_v4);
+	  rc |=
+	    vlib_punt_reason_alloc (punt_hdl, "reason-v6", &punt_reason_v6);
+	  ASSERT (!rc);
+
+	  vnet_feature_enable_disable ("ip4-unicast",
+				       "punt-test-feat-ip4",
+				       sw_if_index, 1, NULL, 0);
+	  vnet_feature_enable_disable ("ip6-unicast",
+				       "punt-test-feat-ip6",
+				       sw_if_index, 1, NULL, 0);
+	  return NULL;
+	}
+
+      if (SW_IF_INDEX_PG0 == sw_if_index)
+	{
+	  if (FIB_PROTOCOL_IP4 == fproto)
+	    {
+	      /*
+	       * register the node that will forward the punted packet
+	       */
+	      vlib_punt_register (punt_hdl, punt_reason_v4,
+				  "punt-test-pg0-ip4");
+	      from = vlib_get_node_by_name (vm, (u8 *) "punt-test-pg0-ip4");
+	    }
+	  else
+	    {
+	      vlib_punt_register (punt_hdl, punt_reason_v6,
+				  "punt-test-pg0-ip6");
+	      from = vlib_get_node_by_name (vm, (u8 *) "punt-test-pg0-ip6");
+	    }
+	}
+      else
+	{
+	  if (FIB_PROTOCOL_IP4 == fproto)
+	    {
+	      vlib_punt_register (punt_hdl, punt_reason_v4,
+				  "punt-test-pg1-ip4");
+	      from = vlib_get_node_by_name (vm, (u8 *) "punt-test-pg1-ip4");
+	    }
+	  else
+	    {
+	      vlib_punt_register (punt_hdl, punt_reason_v6,
+				  "punt-test-pg1-ip6");
+	      from = vlib_get_node_by_name (vm, (u8 *) "punt-test-pg1-ip6");
+	    }
+	}
+
+      vlib_node_add_next (vm, from->index,
+			  vnet_tx_node_index_for_sw_interface
+			  (vnm, sw_if_index));
+
+      vec_validate (adjs[fproto], sw_if_index);
+
+      adjs[fproto][sw_if_index] = adj_nbr_find (fproto,
+						fib_proto_to_link (fproto),
+						&ip46, sw_if_index);
+    }
+
+  return (NULL);
+}
+
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (test_fib_command, static) =
+{
+  .path = "test punt",
+  .short_help = "punt unit tests - DO NOT RUN ON A LIVE SYSTEM",
+  .function = punt_test,
+};
+/* *INDENT-ON* */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */