Payload test

tests-extra/tests/edns/payload_limits/test.py

+#!/usr/bin/env python3
+
+'''Test for maximum UDP payload size with respect to IP family'''
+
+from dnstest.test import Test
+
+t = Test()
+
+server4 = t.server("knot", address=4)
+server6 = t.server("knot", address=6)
+zone = t.zone("flags.")
+
+# Set common payload limit for 512-byte message with 11-byte EDNS section.
+server4.max_udp_payload = 523
+server6.max_udp_payload = 523
+
+t.link(zone, server4)
+t.link(zone, server6)
+
+t.start()
+
+# Check common limit if 512 fits and 513 does not.
+resp = server4.dig("512resp.flags", "TXT", udp=True, bufsize=4096)
+resp.check(noflags="TC")
+
+resp = server4.dig("513resp.flags", "TXT", udp=True, bufsize=4096)
+resp.check(flags="TC")
+
+resp = server6.dig("512resp.flags", "TXT", udp=True, bufsize=4096)
+resp.check(noflags="TC")
+
+resp = server6.dig("513resp.flags", "TXT", udp=True, bufsize=4096)
+resp.check(flags="TC")
+
+# Set IP family specific limit.
+server4.max_udp4_payload = 523
+server4.max_udp6_payload = 524 # Shoud not affect IPv4
+server4.max_udp_payload  = 524 # Shoud not override IPv4 specific
+
+server6.max_udp6_payload = 523
+server6.max_udp4_payload = 524 # Shoul not affect IPv6
+server6.max_udp_payload  = 524 # Shoud not override IPv6 specific
+
+server4.gen_confile()
+server4.reload()
+
+server6.gen_confile()
+server6.reload()
+
+# Check IP specific limit.
+resp = server4.dig("512resp.flags", "TXT", udp=True, bufsize=4069)
+resp.check(noflags="TC")
+
+resp = server4.dig("513resp.flags", "TXT", udp=True, bufsize=4069)
+resp.check(flags="TC")
+
+resp = server6.dig("512resp.flags", "TXT", udp=True, bufsize=4069)
+resp.check(noflags="TC")
+
+resp = server6.dig("513resp.flags", "TXT", udp=True, bufsize=4069)
+resp.check(flags="TC")
+
+t.end()