udp: refactor udp code

Change-Id: I44d5c9df7c49b8d4d5677c6d319033b2da3e6b80
Signed-off-by: Florin Coras <fcoras@cisco.com>

1 files changed, 306 insertions, 0 deletions

diff --git a/src/vnet/session/transport.c b/src/vnet/session/transport.c
new file mode 100644
index 00000000000..fc722e45668
--- /dev/null
+++ b/src/vnet/session/transport.c
@@ -0,0 +1,306 @@
+/*
+ * 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.
+ */
+
+#include <vnet/session/transport_interface.h>
+#include <vnet/session/session.h>
+#include <vnet/fib/fib.h>
+
+/**
+ * Per-type vector of transport protocol virtual function tables
+ */
+transport_proto_vft_t *tp_vfts;
+
+/*
+ * Port allocator seed
+ */
+static u32 port_allocator_seed;
+
+/*
+ * Local endpoints table
+ */
+static transport_endpoint_table_t local_endpoints_table;
+
+/*
+ * Pool of local endpoints
+ */
+static transport_endpoint_t *local_endpoints;
+
+/*
+ * Local endpoints pool lock
+ */
+static clib_spinlock_t local_endpoints_lock;
+
+
+u32
+transport_endpoint_lookup (transport_endpoint_table_t * ht, u8 proto,
+			   ip46_address_t * ip, u16 port)
+{
+  clib_bihash_kv_24_8_t kv;
+  int rv;
+
+  kv.key[0] = ip->as_u64[0];
+  kv.key[1] = ip->as_u64[1];
+  kv.key[2] = (u64) port << 8 | (u64) proto;
+
+  rv = clib_bihash_search_inline_24_8 (ht, &kv);
+  if (rv == 0)
+    return kv.value;
+
+  return ENDPOINT_INVALID_INDEX;
+}
+
+void
+transport_endpoint_table_add (transport_endpoint_table_t * ht, u8 proto,
+			      transport_endpoint_t * te, u32 value)
+{
+  clib_bihash_kv_24_8_t kv;
+
+  kv.key[0] = te->ip.as_u64[0];
+  kv.key[1] = te->ip.as_u64[1];
+  kv.key[2] = (u64) te->port << 8 | (u64) proto;
+  kv.value = value;
+
+  clib_bihash_add_del_24_8 (ht, &kv, 1);
+}
+
+void
+transport_endpoint_table_del (transport_endpoint_table_t * ht, u8 proto,
+			      transport_endpoint_t * te)
+{
+  clib_bihash_kv_24_8_t kv;
+
+  kv.key[0] = te->ip.as_u64[0];
+  kv.key[1] = te->ip.as_u64[1];
+  kv.key[2] = (u64) te->port << 8 | (u64) proto;
+
+  clib_bihash_add_del_24_8 (ht, &kv, 0);
+}
+
+/**
+ * Register transport virtual function table.
+ *
+ * @param type - session type (not protocol type)
+ * @param vft - virtual function table
+ */
+void
+transport_register_protocol (transport_proto_t transport_proto, u8 is_ip4,
+			     const transport_proto_vft_t * vft)
+{
+  u8 session_type;
+  session_type = session_type_from_proto_and_ip (transport_proto, is_ip4);
+
+  vec_validate (tp_vfts, session_type);
+  tp_vfts[session_type] = *vft;
+
+  /* If an offset function is provided, then peek instead of dequeue */
+  session_manager_set_transport_rx_fn (session_type,
+				       vft->tx_fifo_offset != 0);
+}
+
+/**
+ * Get transport virtual function table
+ *
+ * @param type - session type (not protocol type)
+ */
+transport_proto_vft_t *
+transport_protocol_get_vft (u8 session_type)
+{
+  if (session_type >= vec_len (tp_vfts))
+    return 0;
+  return &tp_vfts[session_type];
+}
+
+#define PORT_MASK ((1 << 16)- 1)
+
+void
+transport_endpoint_del (u32 tepi)
+{
+  clib_spinlock_lock_if_init (&local_endpoints_lock);
+  pool_put_index (local_endpoints, tepi);
+  clib_spinlock_unlock_if_init (&local_endpoints_lock);
+}
+
+always_inline transport_endpoint_t *
+transport_endpoint_new (void)
+{
+  transport_endpoint_t *tep;
+  pool_get (local_endpoints, tep);
+  return tep;
+}
+
+void
+transport_endpoint_cleanup (u8 proto, ip46_address_t * lcl_ip, u16 port)
+{
+  u32 tepi;
+  transport_endpoint_t *tep;
+
+  /* Cleanup local endpoint if this was an active connect */
+  tepi = transport_endpoint_lookup (&local_endpoints_table, proto, lcl_ip,
+				    clib_net_to_host_u16 (port));
+  if (tepi != ENDPOINT_INVALID_INDEX)
+    {
+      tep = pool_elt_at_index (local_endpoints, tepi);
+      transport_endpoint_table_del (&local_endpoints_table, proto, tep);
+      transport_endpoint_del (tepi);
+    }
+}
+
+/**
+ * Allocate local port and add if successful add entry to local endpoint
+ * table to mark the pair as used.
+ */
+int
+transport_alloc_local_port (u8 proto, ip46_address_t * ip)
+{
+  transport_endpoint_t *tep;
+  u32 tei;
+  u16 min = 1024, max = 65535;	/* XXX configurable ? */
+  int tries, limit;
+
+  limit = max - min;
+
+  /* Only support active opens from thread 0 */
+  ASSERT (vlib_get_thread_index () == 0);
+
+  /* Search for first free slot */
+  for (tries = 0; tries < limit; tries++)
+    {
+      u16 port = 0;
+
+      /* Find a port in the specified range */
+      while (1)
+	{
+	  port = random_u32 (&port_allocator_seed) & PORT_MASK;
+	  if (PREDICT_TRUE (port >= min && port < max))
+	    break;
+	}
+
+      /* Look it up. If not found, we're done */
+      tei = transport_endpoint_lookup (&local_endpoints_table, proto, ip,
+				       port);
+      if (tei == ENDPOINT_INVALID_INDEX)
+	{
+	  clib_spinlock_lock_if_init (&local_endpoints_lock);
+	  tep = transport_endpoint_new ();
+	  clib_memcpy (&tep->ip, ip, sizeof (*ip));
+	  tep->port = port;
+	  transport_endpoint_table_add (&local_endpoints_table, proto, tep,
+					tep - local_endpoints);
+	  clib_spinlock_unlock_if_init (&local_endpoints_lock);
+
+	  return tep->port;
+	}
+    }
+  return -1;
+}
+
+int
+transport_alloc_local_endpoint (u8 proto, transport_endpoint_t * rmt,
+				ip46_address_t * lcl_addr, u16 * lcl_port)
+{
+  fib_prefix_t prefix;
+  fib_node_index_t fei;
+  u32 sw_if_index;
+  int port;
+
+  /*
+   * Find the local address and allocate port
+   */
+
+  /* Find a FIB path to the destination */
+  clib_memcpy (&prefix.fp_addr, &rmt->ip, sizeof (rmt->ip));
+  prefix.fp_proto = rmt->is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
+  prefix.fp_len = rmt->is_ip4 ? 32 : 128;
+
+  ASSERT (rmt->fib_index != ENDPOINT_INVALID_INDEX);
+  fei = fib_table_lookup (rmt->fib_index, &prefix);
+
+  /* Couldn't find route to destination. Bail out. */
+  if (fei == FIB_NODE_INDEX_INVALID)
+    {
+      clib_warning ("no route to destination");
+      return -1;
+    }
+
+  sw_if_index = rmt->sw_if_index;
+  if (sw_if_index == ENDPOINT_INVALID_INDEX)
+    sw_if_index = fib_entry_get_resolving_interface (fei);
+
+  if (sw_if_index == ENDPOINT_INVALID_INDEX)
+    {
+      clib_warning ("no resolving interface for %U", format_ip46_address,
+		    &rmt->ip, (rmt->is_ip4 == 0) + 1);
+      return -1;
+    }
+
+  memset (lcl_addr, 0, sizeof (*lcl_addr));
+
+  if (rmt->is_ip4)
+    {
+      ip4_address_t *ip4;
+      ip4 = ip_interface_get_first_ip (sw_if_index, 1);
+      lcl_addr->ip4.as_u32 = ip4->as_u32;
+    }
+  else
+    {
+      ip6_address_t *ip6;
+      ip6 = ip_interface_get_first_ip (sw_if_index, 0);
+      if (ip6 == 0)
+	{
+	  clib_warning ("no routable ip6 addresses on %U",
+			format_vnet_sw_if_index_name, vnet_get_main (),
+			sw_if_index);
+	  return -1;
+	}
+      clib_memcpy (&lcl_addr->ip6, ip6, sizeof (*ip6));
+    }
+
+  /* Allocate source port */
+  port = transport_alloc_local_port (proto, lcl_addr);
+  if (port < 1)
+    {
+      clib_warning ("Failed to allocate src port");
+      return -1;
+    }
+  *lcl_port = port;
+  return 0;
+}
+
+void
+transport_init (void)
+{
+  vlib_thread_main_t *vtm = vlib_get_thread_main ();
+  u32 local_endpoints_table_buckets = 250000;
+  u32 local_endpoints_table_memory = 512 << 20;
+  u32 num_threads;
+
+  /* Initialize [port-allocator] random number seed */
+  port_allocator_seed = (u32) clib_cpu_time_now ();
+
+  clib_bihash_init_24_8 (&local_endpoints_table, "local endpoints table",
+			 local_endpoints_table_buckets,
+			 local_endpoints_table_memory);
+  num_threads = 1 /* main thread */  + vtm->n_threads;
+  if (num_threads > 1)
+    clib_spinlock_init (&local_endpoints_lock);
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */