fib: Source Address Selection

Type: feature

Use the FIB to provide SAS (in so far as it is today)
 - Use the glean adjacency as the record of the connected prefixes
 = there's a glean per-{interface, protocol, connected-prefix}
 - Keep the glean up to date with whatever the recieve host prefix is
(since it can change)

Signed-off-by: Neale Ranns <neale.ranns@cisco.com>
Change-Id: I0f3dd1edb1f3fc965af1c7c586709028eb9cdeac

2 files changed, 144 insertions, 25 deletions

diff --git a/test/test_neighbor.py b/test/test_neighbor.py
index 7c13f9ffb0a..241479a1d30 100644
--- a/test/test_neighbor.py
+++ b/test/test_neighbor.py
@@ -7,7 +7,7 @@ from socket import AF_INET, AF_INET6, inet_pton
 from framework import VppTestCase, VppTestRunner
 from vpp_neighbor import VppNeighbor, find_nbr
 from vpp_ip_route import VppIpRoute, VppRoutePath, find_route, \
-    VppIpTable, DpoProto, FibPathType
+    VppIpTable, DpoProto, FibPathType, VppIpInterfaceAddress
 from vpp_papi import VppEnum
 from vpp_ip import VppIpPuntRedirect
 
@@ -1721,6 +1721,95 @@ class ARPTestCase(VppTestCase):
         self.pg1.unconfig_ip4()
         self.pg1.set_table_ip4(0)
 
+    def test_glean_src_select(self):
+        """ Multi Connecteds """
+
+        #
+        # configure multiple connected subnets on an interface
+        # and ensure that ARP requests for hosts on those subnets
+        # pick up the correct source address
+        #
+        conn1 = VppIpInterfaceAddress(self, self.pg1,
+                                      "10.0.0.1", 24).add_vpp_config()
+        conn2 = VppIpInterfaceAddress(self, self.pg1,
+                                      "10.0.1.1", 24).add_vpp_config()
+
+        p1 = (Ether(src=self.pg0.remote_mac,
+                    dst=self.pg0.local_mac) /
+              IP(src=self.pg1.remote_ip4,
+                 dst="10.0.0.128") /
+              Raw(b'0x5' * 100))
+
+        rxs = self.send_and_expect(self.pg0, [p1], self.pg1)
+        for rx in rxs:
+            self.verify_arp_req(rx,
+                                self.pg1.local_mac,
+                                "10.0.0.1",
+                                "10.0.0.128")
+
+        p2 = (Ether(src=self.pg0.remote_mac,
+                    dst=self.pg0.local_mac) /
+              IP(src=self.pg1.remote_ip4,
+                 dst="10.0.1.128") /
+              Raw(b'0x5' * 100))
+
+        rxs = self.send_and_expect(self.pg0, [p2], self.pg1)
+        for rx in rxs:
+            self.verify_arp_req(rx,
+                                self.pg1.local_mac,
+                                "10.0.1.1",
+                                "10.0.1.128")
+
+        #
+        # add a local address in the same subnet
+        #  the source addresses are equivalent. VPP happens to
+        #  choose the last one that was added
+        conn3 = VppIpInterfaceAddress(self, self.pg1,
+                                      "10.0.1.2", 24).add_vpp_config()
+
+        rxs = self.send_and_expect(self.pg0, [p2], self.pg1)
+        for rx in rxs:
+            self.verify_arp_req(rx,
+                                self.pg1.local_mac,
+                                "10.0.1.2",
+                                "10.0.1.128")
+
+        #
+        # remove
+        #
+        conn3.remove_vpp_config()
+        rxs = self.send_and_expect(self.pg0, [p2], self.pg1)
+        for rx in rxs:
+            self.verify_arp_req(rx,
+                                self.pg1.local_mac,
+                                "10.0.1.1",
+                                "10.0.1.128")
+
+        #
+        # add back, this time remove the first one
+        #
+        conn3 = VppIpInterfaceAddress(self, self.pg1,
+                                      "10.0.1.2", 24).add_vpp_config()
+
+        rxs = self.send_and_expect(self.pg0, [p2], self.pg1)
+        for rx in rxs:
+            self.verify_arp_req(rx,
+                                self.pg1.local_mac,
+                                "10.0.1.2",
+                                "10.0.1.128")
+
+        conn1.remove_vpp_config()
+        rxs = self.send_and_expect(self.pg0, [p2], self.pg1)
+        for rx in rxs:
+            self.verify_arp_req(rx,
+                                self.pg1.local_mac,
+                                "10.0.1.2",
+                                "10.0.1.128")
+
+        # cleanup
+        conn3.remove_vpp_config()
+        conn2.remove_vpp_config()
+
 
 class NeighborStatsTestCase(VppTestCase):
     """ ARP/ND Counters """
diff --git a/test/test_ping.py b/test/test_ping.py
index 87cb45c3211..40ad9d4efe0 100644
--- a/test/test_ping.py
+++ b/test/test_ping.py
@@ -7,6 +7,8 @@ from scapy.packet import Raw
 
 from framework import VppTestCase
 from util import ppp
+from vpp_ip_route import VppIpInterfaceAddress
+from vpp_neighbor import VppNeighbor
 
 """ TestPing is a subclass of  VPPTestCase classes.
 
@@ -46,6 +48,21 @@ class TestPing(VppTestCase):
     def show_commands_at_teardown(self):
         self.logger.info(self.vapi.cli("show hardware"))
 
+    def verify_ping_request(self, p, src, dst, seq):
+        ip = p[IP]
+        self.assertEqual(ip.version, 4)
+        self.assertEqual(ip.flags, 0)
+        self.assertEqual(ip.src, src)
+        self.assertEqual(ip.dst, dst)
+        self.assertEqual(ip.proto, 1)
+        self.assertEqual(len(ip.options), 0)
+        self.assertGreaterEqual(ip.ttl, 254)
+        icmp = p[ICMP]
+        self.assertEqual(icmp.type, 8)
+        self.assertEqual(icmp.code, 0)
+        self.assertEqual(icmp.seq, seq)
+        return icmp
+
     def test_ping_basic(self):
         """ basic ping test """
         try:
@@ -62,18 +79,8 @@ class TestPing(VppTestCase):
             icmp_id = None
             icmp_seq = 1
             for p in out:
-                ip = p[IP]
-                self.assertEqual(ip.version, 4)
-                self.assertEqual(ip.flags, 0)
-                self.assertEqual(ip.src, self.pg1.local_ip4)
-                self.assertEqual(ip.dst, self.pg1.remote_ip4)
-                self.assertEqual(ip.proto, 1)
-                self.assertEqual(len(ip.options), 0)
-                self.assertGreaterEqual(ip.ttl, 254)
-                icmp = p[ICMP]
-                self.assertEqual(icmp.type, 8)
-                self.assertEqual(icmp.code, 0)
-                self.assertEqual(icmp.seq, icmp_seq)
+                icmp = self.verify_ping_request(p, self.pg1.local_ip4,
+                                                self.pg1.remote_ip4, icmp_seq)
                 icmp_seq = icmp_seq + 1
                 if icmp_id is None:
                     icmp_id = icmp.id
@@ -98,18 +105,8 @@ class TestPing(VppTestCase):
             icmp_seq = 1
             count = 0
             for p in out:
-                ip = p[IP]
-                self.assertEqual(ip.version, 4)
-                self.assertEqual(ip.flags, 0)
-                self.assertEqual(ip.src, self.pg1.local_ip4)
-                self.assertEqual(ip.dst, self.pg1.remote_ip4)
-                self.assertEqual(ip.proto, 1)
-                self.assertEqual(len(ip.options), 0)
-                self.assertGreaterEqual(ip.ttl, 254)
-                icmp = p[ICMP]
-                self.assertEqual(icmp.type, 8)
-                self.assertEqual(icmp.code, 0)
-                self.assertEqual(icmp.seq, icmp_seq)
+                icmp = self.verify_ping_request(p, self.pg1.local_ip4,
+                                                self.pg1.remote_ip4, icmp_seq)
                 count = count + 1
                 if count >= 3:
                     icmp_seq = icmp_seq + 1
@@ -120,3 +117,36 @@ class TestPing(VppTestCase):
                     self.assertEqual(icmp.id, icmp_id)
         finally:
             self.vapi.cli("show error")
+
+    def test_ping_src(self):
+        """ ping with source address set """
+
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        self.logger.info(self.vapi.cli("show ip4 neighbors"))
+        self.logger.info(self.vapi.cli("show ip6 neighbors"))
+
+        nbr_addr = "10.0.0.2"
+        VppIpInterfaceAddress(self, self.pg1, "10.0.0.1", 24).add_vpp_config()
+        VppNeighbor(self, self.pg1.sw_if_index,
+                    "00:11:22:33:44:55",
+                    nbr_addr).add_vpp_config()
+
+        ping_cmd = "ping %s interval 0.01 repeat 3" % self.pg1.remote_ip4
+        ret = self.vapi.cli(ping_cmd)
+        out = self.pg1.get_capture(3)
+        icmp_seq = 1
+        for p in out:
+            icmp = self.verify_ping_request(p, self.pg1.local_ip4,
+                                            self.pg1.remote_ip4, icmp_seq)
+            icmp_seq = icmp_seq + 1
+
+        self.pg_enable_capture(self.pg_interfaces)
+        self.pg_start()
+        ping_cmd = "ping %s interval 0.01 repeat 3" % nbr_addr
+        ret = self.vapi.cli(ping_cmd)
+        out = self.pg1.get_capture(3)
+        icmp_seq = 1
+        for p in out:
+            icmp = self.verify_ping_request(p, "10.0.0.1", nbr_addr, icmp_seq)
+            icmp_seq = icmp_seq + 1