classify: honor pcap interface filter also when classify filter is used

Type: fix

Change-Id: Ic32550ee9c5d76d232d8b67a7810611f6c8b9177
Signed-off-by: Benoît Ganne <bganne@cisco.com>

1 files changed, 59 insertions, 0 deletions

diff --git a/src/vnet/classify/pcap_classify.h b/src/vnet/classify/pcap_classify.h
new file mode 100644
index 00000000000..1f1c38fd6e6
--- /dev/null
+++ b/src/vnet/classify/pcap_classify.h
@@ -0,0 +1,59 @@
+/*
+ * pcap_classify.h - Use the classifier to decide if a packet is captured
+ *
+ * Copyright (c) 2021 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/vnet.h>
+#include <vnet/classify/vnet_classify.h>
+#include <vnet/classify/trace_classify.h>
+
+/** @file pcap_classify.h
+ * Use the vpp classifier to decide whether to capture packets
+ */
+
+/** @brief vnet_is_packet_pcaped
+ * @param vlib_buffer_t *b - packet to capture
+ * @return 0 => no capture, 1 => capture
+ */
+
+static_always_inline int
+vnet_is_packet_pcaped (vnet_pcap_t *pp, vlib_buffer_t *b, u32 sw_if_index)
+{
+  const u32 pcap_sw_if_index = pp->pcap_sw_if_index;
+  const u32 filter_classify_table_index = pp->filter_classify_table_index;
+
+  if (pcap_sw_if_index != 0)
+    {
+      if (~0 == sw_if_index)
+	sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
+      if (pcap_sw_if_index != sw_if_index)
+	return 0; /* wrong interface, skip */
+    }
+
+  if (filter_classify_table_index != ~0 &&
+      vnet_is_packet_traced_inline (b, filter_classify_table_index,
+				    0 /* full classify */) != 1)
+    return 0; /* not matching the filter, skip */
+
+  return 1; /* success */
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */