mss_clamp: TCP MSS clamping plugin

Type: feature

Configure TCP MSS clamping on an interface as follows:
set interface tcp-mss-clamp [rx|tx] <interface-name>
  ip4 [enable|disable|rx|tx] ip4-mss <size>
  ip6 [enable|disable|rx|tx] ip6-mss <size>

Change-Id: I45b04e50a0b70a33e14a9066f981c651292ebffb
Signed-off-by: Neale Ranns <neale.ranns@cisco.com>
Signed-off-by: Paul Vinciguerra <pvinci@vinciconsulting.com>
Signed-off-by: Miklos Tirpak <miklos.tirpak@gmail.com>
Signed-off-by: Matthew Smith <mgsmith@netgate.com>

1 files changed, 136 insertions, 0 deletions

diff --git a/src/plugins/mss_clamp/mss_clamp_api.c b/src/plugins/mss_clamp/mss_clamp_api.c
new file mode 100644
index 00000000000..cb47cd6ce06
--- /dev/null
+++ b/src/plugins/mss_clamp/mss_clamp_api.c
@@ -0,0 +1,136 @@
+/*
+ * mss_clamp_api.c - TCP MSS clamping plug-in
+ *
+ * Copyright (c) <current-year> <your-organization>
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <vnet/vnet.h>
+#include <vnet/plugin/plugin.h> /* VLIB_PLUGIN_REGISTER */
+#include <mss_clamp/mss_clamp.h>
+#include <mss_clamp/mss_clamp.api_enum.h>
+#include <mss_clamp/mss_clamp.api_types.h>
+#include <vlibapi/api.h>
+#include <vlibmemory/api.h>
+#include <vpp/app/version.h> /* VPP_BUILD_VER */
+
+#define REPLY_MSG_ID_BASE cm->msg_id_base
+#include <vlibapi/api_helper_macros.h>
+
+/* API message handler */
+static void
+vl_api_mss_clamp_enable_disable_t_handler (
+  vl_api_mss_clamp_enable_disable_t *mp)
+{
+  mssc_main_t *cm = &mssc_main;
+  vl_api_mss_clamp_enable_disable_reply_t *rmp;
+  int rv;
+
+  VALIDATE_SW_IF_INDEX (mp);
+
+  rv = mssc_enable_disable (ntohl (mp->sw_if_index), mp->ipv4_direction,
+			    mp->ipv6_direction, ntohs (mp->ipv4_mss),
+			    ntohs (mp->ipv6_mss));
+
+  BAD_SW_IF_INDEX_LABEL;
+  REPLY_MACRO (VL_API_MSS_CLAMP_ENABLE_DISABLE_REPLY);
+}
+
+static void
+send_mss_clamp_details (u32 sw_if_index, vl_api_registration_t *rp,
+			u32 context)
+{
+  mssc_main_t *cm = &mssc_main;
+  vl_api_mss_clamp_details_t *rmp;
+  u16 mss4, mss6;
+  u8 dir4, dir6;
+  int rv;
+
+  mss4 = mss6 = 0;
+  dir4 = dir6 = MSS_CLAMP_DIR_NONE;
+  rv = mssc_get_mss (sw_if_index, &dir4, &dir6, &mss4, &mss6);
+  if (rv == VNET_API_ERROR_FEATURE_DISABLED)
+    return;
+
+  REPLY_MACRO_DETAILS4 (VL_API_MSS_CLAMP_DETAILS, rp, context, ({
+			  rmp->sw_if_index = htonl (sw_if_index);
+			  rmp->ipv4_mss = htons (mss4);
+			  rmp->ipv6_mss = htons (mss6);
+			  rmp->ipv4_direction = dir4;
+			  rmp->ipv6_direction = dir6;
+			}));
+}
+
+static void
+vl_api_mss_clamp_get_t_handler (vl_api_mss_clamp_get_t *mp)
+{
+  mssc_main_t *cm = &mssc_main;
+  vl_api_mss_clamp_get_reply_t *rmp;
+  int rv = 0;
+  u32 sw_if_index = ntohl (mp->sw_if_index);
+  vl_api_registration_t *reg;
+
+  reg = vl_api_client_index_to_registration (mp->client_index);
+  if (!reg)
+    return;
+
+  if (sw_if_index == ~0)
+    {
+      if (vec_len (cm->dir_enabled4) == 0)
+	{
+	  REPLY_MACRO2 (VL_API_MSS_CLAMP_GET_REPLY, ({ rmp->cursor = ~0; }));
+	  return;
+	}
+
+      REPLY_AND_DETAILS_MACRO (
+	VL_API_MSS_CLAMP_GET_REPLY, cm->dir_enabled4,
+	({ send_mss_clamp_details (cursor, reg, mp->context); }));
+    }
+  else
+    {
+      VALIDATE_SW_IF_INDEX (mp);
+      send_mss_clamp_details (sw_if_index, reg, mp->context);
+
+      BAD_SW_IF_INDEX_LABEL;
+      REPLY_MACRO2 (VL_API_MSS_CLAMP_GET_REPLY, ({ rmp->cursor = ~0; }));
+    }
+}
+
+/* API definitions */
+#include <vnet/format_fns.h>
+#include <mss_clamp/mss_clamp.api.c>
+
+/* Set up the API message handling tables */
+static clib_error_t *
+mssc_api_hookup (vlib_main_t *vm)
+{
+  mssc_main_t *cm = &mssc_main;
+
+  cm->msg_id_base = setup_message_id_table ();
+  return 0;
+}
+
+VLIB_API_INIT_FUNCTION (mssc_api_hookup);
+
+VLIB_PLUGIN_REGISTER () = {
+  .version = VPP_BUILD_VER,
+  .description = "TCP MSS clamping plugin",
+};
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */