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.h b/src/vnet/udp/udp.h
new file mode 100644
index 0000000..7ab26ce
--- /dev/null
+++ b/src/vnet/udp/udp.h
@@ -0,0 +1,362 @@
+/*
+ * Copyright (c) 2017 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.
+ */
+#ifndef __included_udp_h__
+#define __included_udp_h__
+
+#include <vnet/vnet.h>
+#include <vnet/udp/udp_packet.h>
+#include <vnet/ip/ip.h>
+#include <vnet/ip/ip4.h>
+#include <vnet/ip/ip4_packet.h>
+#include <vnet/pg/pg.h>
+#include <vnet/ip/format.h>
+
+#include <vnet/ip/ip.h>
+#include <vnet/session/transport.h>
+
+typedef struct
+{
+  transport_connection_t connection;	      /** must be first */
+
+  /** ersatz MTU to limit fifo pushes to test data size */
+  u32 mtu;
+} udp_connection_t;
+
+typedef struct _udp_uri_main
+{
+  /* Per-worker thread udp connection pools */
+  udp_connection_t **udp_sessions;
+  udp_connection_t *udp_listeners;
+
+  /* convenience */
+  vlib_main_t *vlib_main;
+  vnet_main_t *vnet_main;
+  ip4_main_t *ip4_main;
+  ip6_main_t *ip6_main;
+} udp_uri_main_t;
+
+extern udp_uri_main_t udp_uri_main;
+extern vlib_node_registration_t udp4_uri_input_node;
+
+always_inline udp_uri_main_t *
+vnet_get_udp_main ()
+{
+  return &udp_uri_main;
+}
+
+always_inline udp_connection_t *
+udp_connection_get (u32 conn_index, u32 thread_index)
+{
+  return pool_elt_at_index (udp_uri_main.udp_sessions[thread_index],
+			    conn_index);
+}
+
+always_inline udp_connection_t *
+udp_listener_get (u32 conn_index)
+{
+  return pool_elt_at_index (udp_uri_main.udp_listeners, conn_index);
+}
+
+typedef enum
+{
+#define udp_error(n,s) UDP_ERROR_##n,
+#include <vnet/udp/udp_error.def>
+#undef udp_error
+  UDP_N_ERROR,
+} udp_error_t;
+
+#define foreach_udp4_dst_port			\
+_ (67, dhcp_to_server)                          \
+_ (68, dhcp_to_client)                          \
+_ (500, ikev2)                                  \
+_ (3784, bfd4)                                  \
+_ (3785, bfd_echo4)                             \
+_ (4341, lisp_gpe)                              \
+_ (4342, lisp_cp)                          	\
+_ (4739, ipfix)                                 \
+_ (4789, vxlan)					\
+_ (4789, vxlan6)				\
+_ (4790, vxlan_gpe)				\
+_ (6633, vpath_3)
+
+
+#define foreach_udp6_dst_port                   \
+_ (547, dhcpv6_to_server)                       \
+_ (546, dhcpv6_to_client)			\
+_ (3784, bfd6)                                  \
+_ (3785, bfd_echo6)                             \
+_ (4341, lisp_gpe6)                             \
+_ (4342, lisp_cp6)                          	\
+_ (4790, vxlan6_gpe)      \
+_ (6633, vpath6_3)
+
+typedef enum
+{
+#define _(n,f) UDP_DST_PORT_##f = n,
+  foreach_udp4_dst_port foreach_udp6_dst_port
+#undef _
+} udp_dst_port_t;
+
+typedef enum
+{
+#define _(n,f) UDP6_DST_PORT_##f = n,
+  foreach_udp6_dst_port
+#undef _
+} udp6_dst_port_t;
+
+typedef struct
+{
+  /* Name (a c string). */
+  char *name;
+
+  /* GRE protocol type in host byte order. */
+  udp_dst_port_t dst_port;
+
+  /* Node which handles this type. */
+  u32 node_index;
+
+  /* Next index for this type. */
+  u32 next_index;
+} udp_dst_port_info_t;
+
+typedef enum
+{
+  UDP_IP6 = 0,
+  UDP_IP4,			/* the code is full of is_ip4... */
+  N_UDP_AF,
+} udp_af_t;
+
+typedef struct
+{
+  udp_dst_port_info_t *dst_port_infos[N_UDP_AF];
+
+  /* Hash tables mapping name/protocol to protocol info index. */
+  uword *dst_port_info_by_name[N_UDP_AF];
+  uword *dst_port_info_by_dst_port[N_UDP_AF];
+
+  /* convenience */
+  vlib_main_t *vlib_main;
+} udp_main_t;
+
+always_inline udp_dst_port_info_t *
+udp_get_dst_port_info (udp_main_t * um, udp_dst_port_t dst_port, u8 is_ip4)
+{
+  uword *p = hash_get (um->dst_port_info_by_dst_port[is_ip4], dst_port);
+  return p ? vec_elt_at_index (um->dst_port_infos[is_ip4], p[0]) : 0;
+}
+
+format_function_t format_udp_header;
+format_function_t format_udp_rx_trace;
+
+unformat_function_t unformat_udp_header;
+
+void udp_register_dst_port (vlib_main_t * vm,
+			    udp_dst_port_t dst_port,
+			    u32 node_index, u8 is_ip4);
+
+void
+udp_unregister_dst_port (vlib_main_t * vm,
+			 udp_dst_port_t dst_port, u8 is_ip4);
+
+void udp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add);
+
+always_inline void
+ip_udp_fixup_one (vlib_main_t * vm, vlib_buffer_t * b0, u8 is_ip4)
+{
+  u16 new_l0;
+  udp_header_t *udp0;
+
+  if (is_ip4)
+    {
+      ip4_header_t *ip0;
+      ip_csum_t sum0;
+      u16 old_l0 = 0;
+
+      ip0 = vlib_buffer_get_current (b0);
+
+      /* fix the <bleep>ing outer-IP checksum */
+      sum0 = ip0->checksum;
+      /* old_l0 always 0, see the rewrite setup */
+      new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
+
+      sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
+			     length /* changed member */ );
+      ip0->checksum = ip_csum_fold (sum0);
+      ip0->length = new_l0;
+
+      /* Fix UDP length */
+      udp0 = (udp_header_t *) (ip0 + 1);
+      new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
+				     - sizeof (*ip0));
+      udp0->length = new_l0;
+    }
+  else
+    {
+      ip6_header_t *ip0;
+      int bogus0;
+
+      ip0 = vlib_buffer_get_current (b0);
+
+      new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
+				     - sizeof (*ip0));
+      ip0->payload_length = new_l0;
+
+      /* Fix UDP length */
+      udp0 = (udp_header_t *) (ip0 + 1);
+      udp0->length = new_l0;
+
+      udp0->checksum =
+	ip6_tcp_udp_icmp_compute_checksum (vm, b0, ip0, &bogus0);
+      ASSERT (bogus0 == 0);
+
+      if (udp0->checksum == 0)
+	udp0->checksum = 0xffff;
+    }
+}
+
+always_inline void
+ip_udp_encap_one (vlib_main_t * vm, vlib_buffer_t * b0, u8 * ec0, word ec_len,
+		  u8 is_ip4)
+{
+  vlib_buffer_advance (b0, -ec_len);
+
+  if (is_ip4)
+    {
+      ip4_header_t *ip0;
+
+      ip0 = vlib_buffer_get_current (b0);
+
+      /* Apply the encap string. */
+      clib_memcpy (ip0, ec0, ec_len);
+      ip_udp_fixup_one (vm, b0, 1);
+    }
+  else
+    {
+      ip6_header_t *ip0;
+
+      ip0 = vlib_buffer_get_current (b0);
+
+      /* Apply the encap string. */
+      clib_memcpy (ip0, ec0, ec_len);
+      ip_udp_fixup_one (vm, b0, 0);
+    }
+}
+
+always_inline void
+ip_udp_encap_two (vlib_main_t * vm, vlib_buffer_t * b0, vlib_buffer_t * b1,
+		  u8 * ec0, u8 * ec1, word ec_len, u8 is_v4)
+{
+  u16 new_l0, new_l1;
+  udp_header_t *udp0, *udp1;
+
+  ASSERT (_vec_len (ec0) == _vec_len (ec1));
+
+  vlib_buffer_advance (b0, -ec_len);
+  vlib_buffer_advance (b1, -ec_len);
+
+  if (is_v4)
+    {
+      ip4_header_t *ip0, *ip1;
+      ip_csum_t sum0, sum1;
+      u16 old_l0 = 0, old_l1 = 0;
+
+      ip0 = vlib_buffer_get_current (b0);
+      ip1 = vlib_buffer_get_current (b1);
+
+      /* Apply the encap string */
+      clib_memcpy (ip0, ec0, ec_len);
+      clib_memcpy (ip1, ec1, ec_len);
+
+      /* fix the <bleep>ing outer-IP checksum */
+      sum0 = ip0->checksum;
+      sum1 = ip1->checksum;
+
+      /* old_l0 always 0, see the rewrite setup */
+      new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
+      new_l1 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1));
+
+      sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
+			     length /* changed member */ );
+      sum1 = ip_csum_update (sum1, old_l1, new_l1, ip4_header_t,
+			     length /* changed member */ );
+
+      ip0->checksum = ip_csum_fold (sum0);
+      ip1->checksum = ip_csum_fold (sum1);
+
+      ip0->length = new_l0;
+      ip1->length = new_l1;
+
+      /* Fix UDP length */
+      udp0 = (udp_header_t *) (ip0 + 1);
+      udp1 = (udp_header_t *) (ip1 + 1);
+
+      new_l0 =
+	clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0) -
+			      sizeof (*ip0));
+      new_l1 =
+	clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1) -
+			      sizeof (*ip1));
+      udp0->length = new_l0;
+      udp1->length = new_l1;
+    }
+  else
+    {
+      ip6_header_t *ip0, *ip1;
+      int bogus0, bogus1;
+
+      ip0 = vlib_buffer_get_current (b0);
+      ip1 = vlib_buffer_get_current (b1);
+
+      /* Apply the encap string. */
+      clib_memcpy (ip0, ec0, ec_len);
+      clib_memcpy (ip1, ec1, ec_len);
+
+      new_l0 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
+				     - sizeof (*ip0));
+      new_l1 = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1)
+				     - sizeof (*ip1));
+      ip0->payload_length = new_l0;
+      ip1->payload_length = new_l1;
+
+      /* Fix UDP length */
+      udp0 = (udp_header_t *) (ip0 + 1);
+      udp1 = (udp_header_t *) (ip1 + 1);
+
+      udp0->length = new_l0;
+      udp1->length = new_l1;
+
+      udp0->checksum =
+	ip6_tcp_udp_icmp_compute_checksum (vm, b0, ip0, &bogus0);
+      udp1->checksum =
+	ip6_tcp_udp_icmp_compute_checksum (vm, b1, ip1, &bogus1);
+      ASSERT (bogus0 == 0);
+      ASSERT (bogus1 == 0);
+
+      if (udp0->checksum == 0)
+	udp0->checksum = 0xffff;
+      if (udp1->checksum == 0)
+	udp1->checksum = 0xffff;
+    }
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
+
+#endif /* __included_udp_h__ */