reassembly: prevent long chain attack

limit max # of fragments to 3 per packet by default
add API option to configure the limit at runtime

Change-Id: Ie4b9507bf5c6095b9a5925972b37fe0032f4f9e8
Signed-off-by: Klement Sekera <ksekera@cisco.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/test/framework.py b/test/framework.py
index 47de2c4d967..201892aea27 100644
--- a/test/framework.py
+++ b/test/framework.py
@@ -1000,6 +1000,19 @@ class VppTestCase(unittest.TestCase):
         if pkt.haslayer(ICMPv6EchoReply):
             self.assert_checksum_valid(pkt, 'ICMPv6EchoReply', 'cksum')
 
+    def get_packet_counter(self, counter):
+        if counter.startswith("/"):
+            counter_value = self.statistics.get_counter(counter)
+        else:
+            counters = self.vapi.cli("sh errors").split('\n')
+            counter_value = -1
+            for i in range(1, len(counters) - 1):
+                results = counters[i].split()
+                if results[1] == counter:
+                    counter_value = int(results[0])
+                    break
+        return counter_value
+
     def assert_packet_counter_equal(self, counter, expected_value):
         if counter.startswith("/"):
             counter_value = self.statistics.get_counter(counter)