From 808c5b21c2759564689933d004223052b7895a42 Mon Sep 17 00:00:00 2001 From: Neale Ranns Date: Wed, 2 Aug 2017 05:15:07 -0700 Subject: DHCP Client: receive unicast ACKs despite VPP DHCP client setting neither ciaddr nor giaddr and setting the broadcast bit (see RFC 2131 section 4.1) some DHCP servers will still send a unicast DCHPACK. So as not to drop this VPP must have both 1) a receive FIB entry for the OFFERED IP adress and 2) a 'don't drop me because of uRPF' FIB entry for the DHCP server's address. Change-Id: I167d858deb45629318cbdccf5bf67d971730a42f Signed-off-by: Neale Ranns --- test/test_dhcp.py | 92 ++++++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 71 insertions(+), 21 deletions(-) (limited to 'test/test_dhcp.py') diff --git a/test/test_dhcp.py b/test/test_dhcp.py index 4e8ed4cedb7..6fc291824ec 100644 --- a/test/test_dhcp.py +++ b/test/test_dhcp.py @@ -196,6 +196,10 @@ class TestDHCP(VppTestCase): self.verify_dhcp_has_option(pkt, "hostname", hostname) if client_id: self.verify_dhcp_has_option(pkt, "client_id", client_id) + bootp = pkt[BOOTP] + self.assertEqual(bootp.ciaddr, "0.0.0.0") + self.assertEqual(bootp.giaddr, "0.0.0.0") + self.assertEqual(bootp.flags, 0x8000) def verify_orig_dhcp_request(self, pkt, intf, hostname, ip): self.verify_orig_dhcp_pkt(pkt, intf) @@ -203,6 +207,10 @@ class TestDHCP(VppTestCase): self.verify_dhcp_msg_type(pkt, "request") self.verify_dhcp_has_option(pkt, "hostname", hostname) self.verify_dhcp_has_option(pkt, "requested_addr", ip) + bootp = pkt[BOOTP] + self.assertEqual(bootp.ciaddr, "0.0.0.0") + self.assertEqual(bootp.giaddr, "0.0.0.0") + self.assertEqual(bootp.flags, 0x8000) def verify_relayed_dhcp_discover(self, pkt, intf, src_intf=None, fib_id=0, oui=0, @@ -1057,14 +1065,15 @@ class TestDHCP(VppTestCase): # # Sned back on offer, expect the request # - p = (Ether(dst=self.pg2.local_mac, src=self.pg2.remote_mac) / - IP(src=self.pg2.remote_ip4, dst="255.255.255.255") / - UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT) / - BOOTP(op=1, - yiaddr=self.pg2.local_ip4) / - DHCP(options=[('message-type', 'offer'), ('end')])) + p_offer = (Ether(dst=self.pg2.local_mac, src=self.pg2.remote_mac) / + IP(src=self.pg2.remote_ip4, dst="255.255.255.255") / + UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT) / + BOOTP(op=1, yiaddr=self.pg2.local_ip4) / + DHCP(options=[('message-type', 'offer'), + ('server_id', self.pg2.remote_ip4), + ('end')])) - self.pg2.add_stream(p) + self.pg2.add_stream(p_offer) self.pg_enable_capture(self.pg_interfaces) self.pg_start() @@ -1075,19 +1084,18 @@ class TestDHCP(VppTestCase): # # Send an acknowloedgement # - p = (Ether(dst=self.pg2.local_mac, src=self.pg2.remote_mac) / - IP(src=self.pg2.remote_ip4, dst="255.255.255.255") / - UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT) / - BOOTP(op=1, - yiaddr=self.pg2.local_ip4) / - DHCP(options=[('message-type', 'ack'), - ('subnet_mask', "255.255.255.0"), - ('router', self.pg2.remote_ip4), - ('server_id', self.pg2.remote_ip4), - ('lease_time', 43200), - ('end')])) - - self.pg2.add_stream(p) + p_ack = (Ether(dst=self.pg2.local_mac, src=self.pg2.remote_mac) / + IP(src=self.pg2.remote_ip4, dst="255.255.255.255") / + UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT) / + BOOTP(op=1, yiaddr=self.pg2.local_ip4) / + DHCP(options=[('message-type', 'ack'), + ('subnet_mask', "255.255.255.0"), + ('router', self.pg2.remote_ip4), + ('server_id', self.pg2.remote_ip4), + ('lease_time', 43200), + ('end')])) + + self.pg2.add_stream(p_ack) self.pg_enable_capture(self.pg_interfaces) self.pg_start() @@ -1103,6 +1111,7 @@ class TestDHCP(VppTestCase): # At the end of this procedure there should be a connected route # in the FIB # + self.assertTrue(find_route(self, self.pg2.local_ip4, 24)) self.assertTrue(find_route(self, self.pg2.local_ip4, 32)) # remove the left over ARP entry @@ -1119,10 +1128,14 @@ class TestDHCP(VppTestCase): # and now the route should be gone # self.assertFalse(find_route(self, self.pg2.local_ip4, 32)) + self.assertFalse(find_route(self, self.pg2.local_ip4, 24)) # - # Start the procedure again. this time have VPP send the clientiid + # Start the procedure again. this time have VPP send the client-ID # + self.pg2.admin_down() + self.sleep(1) + self.pg2.admin_up() self.vapi.dhcp_client(self.pg2.sw_if_index, hostname, client_id=self.pg2.local_mac) @@ -1131,10 +1144,47 @@ class TestDHCP(VppTestCase): self.verify_orig_dhcp_discover(rx[0], self.pg2, hostname, self.pg2.local_mac) + self.pg2.add_stream(p_offer) + self.pg_enable_capture(self.pg_interfaces) + self.pg_start() + + rx = self.pg2.get_capture(1) + self.verify_orig_dhcp_request(rx[0], self.pg2, hostname, + self.pg2.local_ip4) + + # + # unicast the ack to the offered address + # + p_ack = (Ether(dst=self.pg2.local_mac, src=self.pg2.remote_mac) / + IP(src=self.pg2.remote_ip4, dst=self.pg2.local_ip4) / + UDP(sport=DHCP4_SERVER_PORT, dport=DHCP4_CLIENT_PORT) / + BOOTP(op=1, yiaddr=self.pg2.local_ip4) / + DHCP(options=[('message-type', 'ack'), + ('subnet_mask', "255.255.255.0"), + ('router', self.pg2.remote_ip4), + ('server_id', self.pg2.remote_ip4), + ('lease_time', 43200), + ('end')])) + + self.pg2.add_stream(p_ack) + self.pg_enable_capture(self.pg_interfaces) + self.pg_start() + + # + # At the end of this procedure there should be a connected route + # in the FIB + # + self.assertTrue(find_route(self, self.pg2.local_ip4, 32)) + self.assertTrue(find_route(self, self.pg2.local_ip4, 24)) + # # remove the DHCP config # self.vapi.dhcp_client(self.pg2.sw_if_index, hostname, is_add=0) + self.assertFalse(find_route(self, self.pg2.local_ip4, 32)) + self.assertFalse(find_route(self, self.pg2.local_ip4, 24)) + + if __name__ == '__main__': unittest.main(testRunner=VppTestRunner) -- cgit 1.2.3-korg