session: add support for proxying apps

To enable this, applications set the proxy flag in their attach requests
and pass the transport protocols they want to act as proxies for as part
of the attach options.

When proxy is enabled, session rules that point incoming packets to the
proxy app are addedd to the local and global session tables, if these
scopes are accessible to the app. In particular, in case of the former,
the rule accepts packets from all sources and all ports destined to the
namespace's supporting interface address on any port. While in case of
the latter, a generic any destination and any port rule is addedd.

Change-Id: I791f8c1cc083350f02e26a2ac3bdbbfbfa19ece3
Signed-off-by: Florin Coras <fcoras@cisco.com>

1 files changed, 129 insertions, 2 deletions

diff --git a/src/vnet/session/session_test.c b/src/vnet/session/session_test.c
index bdd4f052adc..4b47754464d 100644
--- a/src/vnet/session/session_test.c
+++ b/src/vnet/session/session_test.c
@@ -124,7 +124,7 @@ session_test_namespace (vlib_main_t * vm, unformat_input_t * input)
   memset (options, 0, sizeof (options));
   memset (intf_mac, 0, sizeof (intf_mac));
 
-  options[APP_OPTIONS_FLAGS] = APP_OPTIONS_FLAGS_BUILTIN_APP;
+  options[APP_OPTIONS_FLAGS] = APP_OPTIONS_FLAGS_IS_BUILTIN;
   options[APP_OPTIONS_FLAGS] |= APP_OPTIONS_FLAGS_ACCEPT_REDIRECT;
   vnet_app_attach_args_t attach_args = {
     .api_client_index = ~0,
@@ -753,7 +753,7 @@ session_test_rules (vlib_main_t * vm, unformat_input_t * input)
   /*
    * Attach server with global and local default scope
    */
-  options[APP_OPTIONS_FLAGS] = APP_OPTIONS_FLAGS_BUILTIN_APP;
+  options[APP_OPTIONS_FLAGS] = APP_OPTIONS_FLAGS_IS_BUILTIN;
   options[APP_OPTIONS_FLAGS] |= APP_OPTIONS_FLAGS_ACCEPT_REDIRECT;
   options[APP_OPTIONS_FLAGS] |= APP_OPTIONS_FLAGS_USE_GLOBAL_SCOPE;
   options[APP_OPTIONS_FLAGS] |= APP_OPTIONS_FLAGS_USE_LOCAL_SCOPE;
@@ -896,6 +896,131 @@ session_test_rules (vlib_main_t * vm, unformat_input_t * input)
   return 0;
 }
 
+static int
+session_test_proxy (vlib_main_t * vm, unformat_input_t * input)
+{
+  u64 options[SESSION_OPTIONS_N_OPTIONS];
+  u32 server_index, app_index;
+  u32 dummy_server_api_index = ~0, sw_if_index = 0;
+  clib_error_t *error = 0;
+  u8 segment_name[128], intf_mac[6], sst;
+  stream_session_t *s;
+  transport_connection_t *tc;
+  u16 lcl_port = 1234, rmt_port = 4321;
+  app_namespace_t *app_ns;
+  int verbose = 0;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "verbose"))
+	verbose = 1;
+      else
+	{
+	  vlib_cli_output (vm, "parse error: '%U'", format_unformat_error,
+			   input);
+	  return -1;
+	}
+    }
+
+  ip4_address_t lcl_ip = {
+    .as_u32 = clib_host_to_net_u32 (0x01020304),
+  };
+  ip4_address_t rmt_ip = {
+    .as_u32 = clib_host_to_net_u32 (0x05060708),
+  };
+  fib_prefix_t rmt_pref = {
+    .fp_addr.ip4.as_u32 = rmt_ip.as_u32,
+    .fp_len = 16,
+    .fp_proto = FIB_PROTOCOL_IP4,
+  };
+  session_endpoint_t sep = {
+    .ip = rmt_pref.fp_addr,
+    .is_ip4 = 1,
+    .port = rmt_port,
+    .transport_proto = TRANSPORT_PROTO_TCP,
+  };
+
+  /*
+   * Create loopback interface
+   */
+  memset (intf_mac, 0, sizeof (intf_mac));
+  if (vnet_create_loopback_interface (&sw_if_index, intf_mac, 0, 0))
+    {
+      clib_warning ("couldn't create loopback. stopping the test!");
+      return 0;
+    }
+  vnet_sw_interface_set_flags (vnet_get_main (), sw_if_index,
+			       VNET_SW_INTERFACE_FLAG_ADMIN_UP);
+  ip4_add_del_interface_address (vlib_get_main (), sw_if_index, &lcl_ip,
+				 24, 0);
+
+  app_ns = app_namespace_get_default ();
+  app_ns->sw_if_index = sw_if_index;
+
+  memset (options, 0, sizeof (options));
+  options[APP_OPTIONS_FLAGS] |= APP_OPTIONS_FLAGS_ACCEPT_REDIRECT;
+  options[APP_OPTIONS_FLAGS] |= APP_OPTIONS_FLAGS_IS_PROXY;
+  options[APP_OPTIONS_PROXY_TRANSPORT] = 1 << TRANSPORT_PROTO_TCP;
+  options[APP_OPTIONS_FLAGS] |= APP_OPTIONS_FLAGS_USE_GLOBAL_SCOPE;
+  options[APP_OPTIONS_FLAGS] |= APP_OPTIONS_FLAGS_USE_LOCAL_SCOPE;
+  vnet_app_attach_args_t attach_args = {
+    .api_client_index = ~0,
+    .options = options,
+    .namespace_id = 0,
+    .session_cb_vft = &dummy_session_cbs,
+    .segment_name = segment_name,
+  };
+
+  attach_args.api_client_index = dummy_server_api_index;
+  error = vnet_application_attach (&attach_args);
+  SESSION_TEST ((error == 0), "server attachment should work");
+  server_index = attach_args.app_index;
+
+  if (verbose)
+    session_lookup_dump_rules_table (0, FIB_PROTOCOL_IP4,
+				     TRANSPORT_PROTO_TCP);
+
+  tc = session_lookup_connection_wt4 (0, &lcl_ip, &rmt_ip, lcl_port, rmt_port,
+				      TRANSPORT_PROTO_TCP, 0);
+  SESSION_TEST ((tc != 0), "lookup 1.2.3.4 1234 5.6.7.8 4321 should be "
+		"successful");
+  sst = session_type_from_proto_and_ip (TRANSPORT_PROTO_TCP, 1);
+  s = listen_session_get (sst, tc->s_index);
+  SESSION_TEST ((s->app_index == server_index), "lookup should return the"
+		" server");
+
+  tc = session_lookup_connection_wt4 (0, &rmt_ip, &rmt_ip, lcl_port, rmt_port,
+				      TRANSPORT_PROTO_TCP, 0);
+  SESSION_TEST ((tc == 0), "lookup 5.6.7.8 1234 5.6.7.8 4321 should"
+		" not work");
+
+  if (verbose)
+    session_lookup_dump_local_rules_table (app_ns->local_table_index,
+					   FIB_PROTOCOL_IP4,
+					   TRANSPORT_PROTO_TCP);
+  app_index =
+    session_lookup_local_session_endpoint (app_ns->local_table_index, &sep);
+  SESSION_TEST ((app_index == server_index), "local session endpoint lookup"
+		" should work");
+
+  vnet_app_detach_args_t detach_args = {
+    .app_index = server_index,
+  };
+  vnet_application_detach (&detach_args);
+
+  if (verbose)
+    session_lookup_dump_local_rules_table (app_ns->local_table_index,
+					   FIB_PROTOCOL_IP4,
+					   TRANSPORT_PROTO_TCP);
+
+  app_index =
+    session_lookup_local_session_endpoint (app_ns->local_table_index, &sep);
+  SESSION_TEST ((app_index == SESSION_RULES_TABLE_INVALID_INDEX),
+		"local session endpoint lookup should not work after detach");
+
+  return 0;
+}
+
 static clib_error_t *
 session_test (vlib_main_t * vm,
 	      unformat_input_t * input, vlib_cli_command_t * cmd_arg)
@@ -914,6 +1039,8 @@ session_test (vlib_main_t * vm,
 	res = session_test_rule_table (vm, input);
       else if (unformat (input, "rules"))
 	res = session_test_rules (vm, input);
+      else if (unformat (input, "proxy"))
+	res = session_test_proxy (vm, input);
       else
 	break;
     }