NAT: DS-Lite (VPP-1040)

Dual-Stack Lite enables a broadband service provider to share IPv4 addresses among customers by combining two well-known technologies: IPv4-in-IPv6 and NAT.

Change-Id: I039740f8548c623cd1ac89b8ecda1a6cc4aafb9c
Signed-off-by: Matus Fabian <matfabia@cisco.com>

1 files changed, 164 insertions, 0 deletions

diff --git a/src/plugins/nat/dslite.c b/src/plugins/nat/dslite.c
new file mode 100644
index 00000000000..c86cc8d7e1d
--- /dev/null
+++ b/src/plugins/nat/dslite.c
@@ -0,0 +1,164 @@
+/*
+ * 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 <nat/dslite.h>
+#include <nat/dslite_dpo.h>
+#include <vnet/fib/fib_table.h>
+
+dslite_main_t dslite_main;
+
+void
+dslite_init (vlib_main_t * vm)
+{
+  dslite_main_t *dm = &dslite_main;
+  vlib_thread_registration_t *tr;
+  vlib_thread_main_t *tm = vlib_get_thread_main ();
+  uword *p;
+  dslite_per_thread_data_t *td;
+  u32 translation_buckets = 1024;
+  u32 translation_memory_size = 128 << 20;
+  u32 b4_buckets = 128;
+  u32 b4_memory_size = 64 << 20;
+
+  dm->first_worker_index = 0;
+  dm->num_workers = 0;
+
+  p = hash_get_mem (tm->thread_registrations_by_name, "workers");
+  if (p)
+    {
+      tr = (vlib_thread_registration_t *) p[0];
+      if (tr)
+	{
+	  dm->num_workers = tr->count;
+	  dm->first_worker_index = tr->first_index;
+	}
+    }
+
+  if (dm->num_workers)
+    dm->port_per_thread = (0xffff - 1024) / dm->num_workers;
+  else
+    dm->port_per_thread = 0xffff - 1024;
+
+  vec_validate (dm->per_thread_data, tm->n_vlib_mains - 1);
+
+  /* *INDENT-OFF* */
+  vec_foreach (td, dm->per_thread_data)
+    {
+      clib_bihash_init_24_8 (&td->in2out, "in2out", translation_buckets,
+                             translation_memory_size);
+
+      clib_bihash_init_8_8 (&td->out2in, "out2in", translation_buckets,
+                            translation_memory_size);
+
+      clib_bihash_init_16_8 (&td->b4_hash, "b4s", b4_buckets, b4_memory_size);
+    }
+  /* *INDENT-ON* */
+
+  dslite_dpo_module_init ();
+}
+
+int
+dslite_set_aftr_ip6_addr (dslite_main_t * dm, ip6_address_t * addr)
+{
+  dpo_id_t dpo_v6 = DPO_INVALID;
+
+  dslite_dpo_create (DPO_PROTO_IP6, 0, &dpo_v6);
+  fib_prefix_t pfx = {
+    .fp_proto = FIB_PROTOCOL_IP6,
+    .fp_len = 128,
+    .fp_addr.ip6.as_u64[0] = addr->as_u64[0],
+    .fp_addr.ip6.as_u64[1] = addr->as_u64[1],
+  };
+  fib_table_entry_special_dpo_add (0, &pfx, FIB_SOURCE_PLUGIN_HI,
+				   FIB_ENTRY_FLAG_EXCLUSIVE, &dpo_v6);
+  dpo_reset (&dpo_v6);
+
+  dm->aftr_ip6_addr.as_u64[0] = addr->as_u64[0];
+  dm->aftr_ip6_addr.as_u64[1] = addr->as_u64[1];
+  return 0;
+}
+
+int
+dslite_add_del_pool_addr (dslite_main_t * dm, ip4_address_t * addr, u8 is_add)
+{
+  vlib_thread_main_t *tm = vlib_get_thread_main ();
+  snat_address_t *a = 0;
+  int i = 0;
+  dpo_id_t dpo_v4 = DPO_INVALID;
+  fib_prefix_t pfx = {
+    .fp_proto = FIB_PROTOCOL_IP4,
+    .fp_len = 32,
+    .fp_addr.ip4.as_u32 = addr->as_u32,
+  };
+
+  for (i = 0; i < vec_len (dm->addr_pool); i++)
+    {
+      if (dm->addr_pool[i].addr.as_u32 == addr->as_u32)
+	{
+	  a = dm->addr_pool + i;
+	  break;
+	}
+    }
+  if (is_add)
+    {
+      if (a)
+	return VNET_API_ERROR_VALUE_EXIST;
+      vec_add2 (dm->addr_pool, a, 1);
+      a->addr = *addr;
+#define _(N, i, n, s) \
+      clib_bitmap_alloc (a->busy_##n##_port_bitmap, 65535); \
+      a->busy_##n##_ports = 0; \
+      vec_validate_init_empty (a->busy_##n##_ports_per_thread, tm->n_vlib_mains - 1, 0);
+      foreach_snat_protocol
+#undef _
+	dslite_dpo_create (DPO_PROTO_IP4, 0, &dpo_v4);
+      fib_table_entry_special_dpo_add (0, &pfx, FIB_SOURCE_PLUGIN_HI,
+				       FIB_ENTRY_FLAG_EXCLUSIVE, &dpo_v4);
+      dpo_reset (&dpo_v4);
+    }
+  else
+    {
+      if (!a)
+	return VNET_API_ERROR_NO_SUCH_ENTRY;
+#define _(N, id, n, s) \
+      clib_bitmap_free (a->busy_##n##_port_bitmap); \
+      vec_free (a->busy_##n##_ports_per_thread);
+      foreach_snat_protocol
+#undef _
+	fib_table_entry_special_remove (0, &pfx, FIB_SOURCE_PLUGIN_HI);
+      vec_del1 (dm->addr_pool, i);
+    }
+  return 0;
+}
+
+u8 *
+format_dslite_trace (u8 * s, va_list * args)
+{
+  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+  dslite_trace_t *t = va_arg (*args, dslite_trace_t *);
+
+  s =
+    format (s, "next index %d, session %d", t->next_index, t->session_index);
+
+  return s;
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */