VPP-598: tcp stack initial commit

Change-Id: I49e5ce0aae6e4ff634024387ceaf7dbc432a0351
Signed-off-by: Dave Barach <dave@barachs.net>
Signed-off-by: Florin Coras <fcoras@cisco.com>
diff --git a/src/vnet/udp/udp.c b/src/vnet/udp/udp.c
new file mode 100644
index 0000000..9e74046
--- /dev/null
+++ b/src/vnet/udp/udp.c
@@ -0,0 +1,342 @@
+/*
+ * Copyright (c) 2016 Cisco and/or its affiliates.
+ * 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.
+ */
+
+/** @file
+    udp state machine, etc.
+*/
+
+#include <vnet/udp/udp.h>
+#include <vnet/session/session.h>
+#include <vnet/dpo/load_balance.h>
+#include <vnet/fib/ip4_fib.h>
+
+udp_uri_main_t udp_uri_main;
+
+u32
+udp_session_bind_ip4 (vlib_main_t * vm, u32 session_index,
+		      ip46_address_t * ip, u16 port_number_host_byte_order)
+{
+  udp_uri_main_t *um = vnet_get_udp_main ();
+  udp_connection_t *listener;
+
+  pool_get (um->udp_listeners, listener);
+  memset (listener, 0, sizeof (udp_connection_t));
+  listener->c_lcl_port = clib_host_to_net_u16 (port_number_host_byte_order);
+  listener->c_lcl_ip4.as_u32 = ip->ip4.as_u32;
+  listener->c_proto = SESSION_TYPE_IP4_UDP;
+  udp_register_dst_port (um->vlib_main, port_number_host_byte_order,
+			 udp4_uri_input_node.index, 1 /* is_ipv4 */ );
+  return 0;
+}
+
+u32
+udp_session_bind_ip6 (vlib_main_t * vm, u32 session_index,
+		      ip46_address_t * ip, u16 port_number_host_byte_order)
+{
+  udp_uri_main_t *um = vnet_get_udp_main ();
+  udp_connection_t *listener;
+
+  pool_get (um->udp_listeners, listener);
+  listener->c_lcl_port = clib_host_to_net_u16 (port_number_host_byte_order);
+  clib_memcpy (&listener->c_lcl_ip6, &ip->ip6, sizeof (ip6_address_t));
+  listener->c_proto = SESSION_TYPE_IP6_UDP;
+  udp_register_dst_port (um->vlib_main, port_number_host_byte_order,
+			 udp4_uri_input_node.index, 0 /* is_ipv4 */ );
+  return 0;
+}
+
+u32
+udp_session_unbind_ip4 (vlib_main_t * vm, u32 listener_index)
+{
+  udp_connection_t *listener;
+  listener = udp_listener_get (listener_index);
+
+  /* deregister the udp_local mapping */
+  udp_unregister_dst_port (vm, listener->c_lcl_port, 1 /* is_ipv4 */ );
+  return 0;
+}
+
+u32
+udp_session_unbind_ip6 (vlib_main_t * vm, u32 listener_index)
+{
+  udp_connection_t *listener;
+
+  listener = udp_listener_get (listener_index);
+
+  /* deregister the udp_local mapping */
+  udp_unregister_dst_port (vm, listener->c_lcl_port, 0 /* is_ipv4 */ );
+  return 0;
+}
+
+transport_connection_t *
+udp_session_get_listener (u32 listener_index)
+{
+  udp_connection_t *us;
+
+  us = udp_listener_get (listener_index);
+  return &us->connection;
+}
+
+u32
+udp_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
+{
+  udp_connection_t *us;
+  u8 *data;
+  udp_header_t *udp;
+
+  us = (udp_connection_t *) tconn;
+
+  if (tconn->is_ip4)
+    {
+      ip4_header_t *ip;
+
+      data = vlib_buffer_get_current (b);
+      udp = (udp_header_t *) (data - sizeof (udp_header_t));
+      ip = (ip4_header_t *) ((u8 *) udp - sizeof (ip4_header_t));
+
+      /* Build packet header, swap rx key src + dst fields */
+      ip->src_address.as_u32 = us->c_lcl_ip4.as_u32;
+      ip->dst_address.as_u32 = us->c_rmt_ip4.as_u32;
+      ip->ip_version_and_header_length = 0x45;
+      ip->ttl = 254;
+      ip->protocol = IP_PROTOCOL_UDP;
+      ip->length = clib_host_to_net_u16 (b->current_length + sizeof (*udp));
+      ip->checksum = ip4_header_checksum (ip);
+
+      udp->src_port = us->c_lcl_port;
+      udp->dst_port = us->c_rmt_port;
+      udp->length = clib_host_to_net_u16 (b->current_length);
+      udp->checksum = 0;
+
+      b->current_length = sizeof (*ip) + sizeof (*udp);
+      return SESSION_QUEUE_NEXT_IP4_LOOKUP;
+    }
+  else
+    {
+      vlib_main_t *vm = vlib_get_main ();
+      ip6_header_t *ip;
+      u16 payload_length;
+      int bogus = ~0;
+
+      data = vlib_buffer_get_current (b);
+      udp = (udp_header_t *) (data - sizeof (udp_header_t));
+      ip = (ip6_header_t *) ((u8 *) udp - sizeof (ip6_header_t));
+
+      /* Build packet header, swap rx key src + dst fields */
+      clib_memcpy (&ip->src_address, &us->c_lcl_ip6, sizeof (ip6_address_t));
+      clib_memcpy (&ip->dst_address, &us->c_rmt_ip6, sizeof (ip6_address_t));
+
+      ip->ip_version_traffic_class_and_flow_label =
+	clib_host_to_net_u32 (0x6 << 28);
+
+      ip->hop_limit = 0xff;
+      ip->protocol = IP_PROTOCOL_UDP;
+
+      payload_length = vlib_buffer_length_in_chain (vm, b);
+      payload_length -= sizeof (*ip);
+
+      ip->payload_length = clib_host_to_net_u16 (payload_length);
+
+      udp->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b, ip, &bogus);
+      ASSERT (!bogus);
+
+      udp->src_port = us->c_lcl_port;
+      udp->dst_port = us->c_rmt_port;
+      udp->length = clib_host_to_net_u16 (b->current_length);
+      udp->checksum = 0;
+
+      b->current_length = sizeof (*ip) + sizeof (*udp);
+
+      return SESSION_QUEUE_NEXT_IP6_LOOKUP;
+    }
+}
+
+transport_connection_t *
+udp_session_get (u32 connection_index, u32 my_thread_index)
+{
+  udp_uri_main_t *um = vnet_get_udp_main ();
+
+  udp_connection_t *us;
+  us =
+    pool_elt_at_index (um->udp_sessions[my_thread_index], connection_index);
+  return &us->connection;
+}
+
+void
+udp_session_close (u32 connection_index, u32 my_thread_index)
+{
+  udp_uri_main_t *um = vnet_get_udp_main ();
+  pool_put_index (um->udp_sessions[my_thread_index], connection_index);
+}
+
+u8 *
+format_udp_session_ip4 (u8 * s, va_list * args)
+{
+  u32 uci = va_arg (*args, u32);
+  u32 thread_index = va_arg (*args, u32);
+  udp_connection_t *u4;
+
+  u4 = udp_connection_get (uci, thread_index);
+
+  s = format (s, "[%s] %U:%d->%U:%d", "udp", format_ip4_address,
+	      &u4->c_lcl_ip4, clib_net_to_host_u16 (u4->c_lcl_port),
+	      format_ip4_address, &u4->c_rmt_ip4,
+	      clib_net_to_host_u16 (u4->c_rmt_port));
+  return s;
+}
+
+u8 *
+format_udp_session_ip6 (u8 * s, va_list * args)
+{
+  u32 uci = va_arg (*args, u32);
+  u32 thread_index = va_arg (*args, u32);
+  udp_connection_t *tc = udp_connection_get (uci, thread_index);
+  s = format (s, "[%s] %U:%d->%U:%d", "udp", format_ip6_address,
+	      &tc->c_lcl_ip6, clib_net_to_host_u16 (tc->c_lcl_port),
+	      format_ip6_address, &tc->c_rmt_ip6,
+	      clib_net_to_host_u16 (tc->c_rmt_port));
+  return s;
+}
+
+u8 *
+format_udp_listener_session_ip4 (u8 * s, va_list * args)
+{
+  u32 tci = va_arg (*args, u32);
+  udp_connection_t *tc = udp_listener_get (tci);
+  s = format (s, "[%s] %U:%d->%U:%d", "udp", format_ip4_address,
+	      &tc->c_lcl_ip4, clib_net_to_host_u16 (tc->c_lcl_port),
+	      format_ip4_address, &tc->c_rmt_ip4,
+	      clib_net_to_host_u16 (tc->c_rmt_port));
+  return s;
+}
+
+u8 *
+format_udp_listener_session_ip6 (u8 * s, va_list * args)
+{
+  u32 tci = va_arg (*args, u32);
+  udp_connection_t *tc = udp_listener_get (tci);
+  s = format (s, "[%s] %U:%d->%U:%d", "udp", format_ip6_address,
+	      &tc->c_lcl_ip6, clib_net_to_host_u16 (tc->c_lcl_port),
+	      format_ip6_address, &tc->c_rmt_ip6,
+	      clib_net_to_host_u16 (tc->c_rmt_port));
+  return s;
+}
+
+u16
+udp_send_mss_uri (transport_connection_t * t)
+{
+  /* TODO figure out MTU of output interface */
+  return 400;
+}
+
+u32
+udp_send_space_uri (transport_connection_t * t)
+{
+  /* No constraint on TX window */
+  return ~0;
+}
+
+int
+udp_open_connection (ip46_address_t * addr, u16 port)
+{
+  clib_warning ("Not implemented");
+  return 0;
+}
+
+/* *INDENT-OFF* */
+const static transport_proto_vft_t udp4_proto = {
+  .bind = udp_session_bind_ip4,
+  .open = udp_open_connection,
+  .unbind = udp_session_unbind_ip4,
+  .push_header = udp_push_header,
+  .get_connection = udp_session_get,
+  .get_listener = udp_session_get_listener,
+  .close = udp_session_close,
+  .send_mss = udp_send_mss_uri,
+  .send_space = udp_send_space_uri,
+  .format_connection = format_udp_session_ip4,
+  .format_listener = format_udp_listener_session_ip4
+};
+
+const static transport_proto_vft_t udp6_proto = {
+  .bind = udp_session_bind_ip6,
+  .open = udp_open_connection,
+  .unbind = udp_session_unbind_ip6,
+  .push_header = udp_push_header,
+  .get_connection = udp_session_get,
+  .get_listener = udp_session_get_listener,
+  .close = udp_session_close,
+  .send_mss = udp_send_mss_uri,
+  .send_space = udp_send_space_uri,
+  .format_connection = format_udp_session_ip6,
+  .format_listener = format_udp_listener_session_ip6
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+udp_init (vlib_main_t * vm)
+{
+  udp_uri_main_t *um = vnet_get_udp_main ();
+  ip_main_t *im = &ip_main;
+  vlib_thread_main_t *tm = vlib_get_thread_main ();
+  u32 num_threads;
+  clib_error_t *error = 0;
+  ip_protocol_info_t *pi;
+
+  um->vlib_main = vm;
+  um->vnet_main = vnet_get_main ();
+
+  if ((error = vlib_call_init_function (vm, ip_main_init)))
+    return error;
+  if ((error = vlib_call_init_function (vm, ip4_lookup_init)))
+    return error;
+  if ((error = vlib_call_init_function (vm, ip6_lookup_init)))
+    return error;
+
+  /*
+   * Registrations
+   */
+
+  /* IP registration */
+  pi = ip_get_protocol_info (im, IP_PROTOCOL_UDP);
+  if (pi == 0)
+    return clib_error_return (0, "UDP protocol info AWOL");
+  pi->format_header = format_udp_header;
+  pi->unformat_pg_edit = unformat_pg_udp_header;
+
+
+  /* Register as transport with URI */
+  session_register_transport (SESSION_TYPE_IP4_UDP, &udp4_proto);
+  session_register_transport (SESSION_TYPE_IP6_UDP, &udp6_proto);
+
+  /*
+   * Initialize data structures
+   */
+
+  num_threads = 1 /* main thread */  + tm->n_threads;
+  vec_validate (um->udp_sessions, num_threads - 1);
+
+  return error;
+}
+
+VLIB_INIT_FUNCTION (udp_init);
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */