tracenode: filtering feature

In order to be able to filter on encapsulated packet, a new node
has been added to the ip4/6-unicast arcs.

Type: feature
Change-Id: I1e8ee05bc6d0fce20cadd8319c81bab260c17d21
Signed-off-by: Maxime Peim <mpeim@cisco.com>

1 files changed, 145 insertions, 0 deletions

diff --git a/src/plugins/tracenode/node.c b/src/plugins/tracenode/node.c
new file mode 100644
index 00000000000..444d93f1708
--- /dev/null
+++ b/src/plugins/tracenode/node.c
@@ -0,0 +1,145 @@
+/*
+ * Copyright (c) 2023 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/feature/feature.h>
+#include <vnet/classify/pcap_classify.h>
+
+typedef struct
+{
+  u32 sw_if_index;
+} tracenode_trace_t;
+
+static u8 *
+format_tracenode_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 *);
+  vnet_main_t *vnm = vnet_get_main ();
+  tracenode_trace_t *t = va_arg (*args, tracenode_trace_t *);
+
+  s = format (s, "Packet traced from interface %U added",
+	      format_vnet_sw_if_index_name, vnm, t->sw_if_index);
+  return s;
+}
+
+static_always_inline u32
+tracenode_inline (vlib_main_t *vm, vlib_node_runtime_t *node,
+		  vlib_frame_t *frame, int is_pcap)
+{
+  vnet_main_t *vnm = vnet_get_main ();
+  vnet_pcap_t *pp = &vnm->pcap;
+  vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b = bufs;
+  u16 nexts[VLIB_FRAME_SIZE], *next = nexts;
+  u32 *from = vlib_frame_vector_args (frame), *from0 = from;
+  const u32 n_tot = frame->n_vectors;
+  u32 n_left = n_tot;
+
+  vlib_get_buffers (vm, from, b, n_tot);
+
+  while (n_left > 0)
+    {
+      /* TODO: dual/quad loop */
+
+      /* enqueue b0 to the current next frame */
+      vnet_feature_next_u16 (next, b[0]);
+
+      /* buffer already traced */
+      if (PREDICT_FALSE (b[0]->flags & VLIB_BUFFER_IS_TRACED))
+	goto skip;
+
+      if (is_pcap && vnet_is_packet_pcaped (pp, b[0], ~0))
+	{
+	  pcap_add_buffer (&pp->pcap_main, vm, from0[0],
+			   pp->max_bytes_per_pkt);
+	}
+      else if (!is_pcap && vlib_trace_buffer (vm, node, next[0], b[0],
+					      1 /* follow_chain */))
+	{
+	  tracenode_trace_t *tr = vlib_add_trace (vm, node, b[0], sizeof *tr);
+	  tr->sw_if_index = vnet_buffer (b[0])->sw_if_index[VLIB_RX];
+	}
+
+    skip:
+      b++;
+      from0++;
+      next++;
+      n_left--;
+    }
+
+  vlib_buffer_enqueue_to_next (vm, node, from, nexts, n_tot);
+  return n_tot;
+}
+
+VLIB_NODE_FN (trace_filtering_node)
+(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
+{
+  return tracenode_inline (vm, node, frame, 0 /* is_pcap */);
+}
+
+VLIB_NODE_FN (pcap_filtering_node)
+(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
+{
+  return tracenode_inline (vm, node, frame, 1 /* is_pcap */);
+}
+
+VLIB_REGISTER_NODE (trace_filtering_node) = {
+  .name = "trace-filtering",
+  .vector_size = sizeof (u32),
+  .type = VLIB_NODE_TYPE_INTERNAL,
+  .format_trace = format_tracenode_trace,
+};
+
+VLIB_REGISTER_NODE (pcap_filtering_node) = {
+  .name = "pcap-filtering",
+  .vector_size = sizeof (u32),
+  .type = VLIB_NODE_TYPE_INTERNAL,
+  .format_trace = format_tracenode_trace,
+};
+
+VNET_FEATURE_INIT (trace_filtering4, static) = {
+  .arc_name = "ip4-unicast",
+  .node_name = "trace-filtering",
+  .runs_after = VNET_FEATURES ("ip4-full-reassembly-feature",
+			       "ip4-sv-reassembly-feature"),
+};
+
+VNET_FEATURE_INIT (trace_filtering6, static) = {
+  .arc_name = "ip6-unicast",
+  .node_name = "trace-filtering",
+  .runs_after = VNET_FEATURES ("ip6-full-reassembly-feature",
+			       "ip6-sv-reassembly-feature"),
+};
+
+VNET_FEATURE_INIT (pcap_filtering4, static) = {
+  .arc_name = "ip4-unicast",
+  .node_name = "pcap-filtering",
+  .runs_after = VNET_FEATURES ("ip4-full-reassembly-feature",
+			       "ip4-sv-reassembly-feature"),
+};
+
+VNET_FEATURE_INIT (pcap_filtering6, static) = {
+  .arc_name = "ip6-unicast",
+  .node_name = "pcap-filtering",
+  .runs_after = VNET_FEATURES ("ip6-full-reassembly-feature",
+			       "ip6-sv-reassembly-feature"),
+};
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */