cnat: Introduce parametric source policy

Type: feature

Change-Id: I60ae9dd1c100b587d1902a20596b99a5c8a95df7
Signed-off-by: Nathan Skrzypczak <nathan.skrzypczak@gmail.com>

1 files changed, 78 insertions, 0 deletions

diff --git a/src/plugins/cnat/cnat_src_policy.h b/src/plugins/cnat/cnat_src_policy.h
new file mode 100644
index 00000000000..d76de8bd2cd
--- /dev/null
+++ b/src/plugins/cnat/cnat_src_policy.h
@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 2020 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 __CNAT_SRC_POLICY_H__
+#define __CNAT_SRC_POLICY_H__
+
+// #include <vnet/udp/udp.h>
+#include <cnat/cnat_types.h>
+#include <cnat/cnat_session.h>
+#include <cnat/cnat_translation.h>
+
+typedef enum
+{
+  CNAT_SPORT_PROTO_TCP,
+  CNAT_SPORT_PROTO_UDP,
+  CNAT_SPORT_PROTO_ICMP,
+  CNAT_SPORT_PROTO_ICMP6,
+  CNAT_N_SPORT_PROTO
+} cnat_sport_proto_t;
+
+typedef enum cnat_source_policy_errors_
+{
+  CNAT_SOURCE_ERROR_EXHAUSTED_PORTS,
+  CNAT_SOURCE_ERROR_USE_DEFAULT,
+  CNAT_SOURCE_N_ERRORS,
+} cnat_source_policy_errors_t;
+
+typedef struct cnat_src_port_allocator_
+{
+  /* Source ports bitmap for snat */
+  clib_bitmap_t *bmap;
+
+  /* Lock for src_ports access */
+  clib_spinlock_t lock;
+} cnat_src_port_allocator_t;
+
+/* function to use to compute source (IP, port) for a new session to a vip */
+typedef cnat_source_policy_errors_t (*cnat_vip_source_policy_t)
+  (vlib_main_t * vm, vlib_buffer_t * b, cnat_session_t * session,
+   u32 * rsession_flags, const cnat_translation_t * ct,
+   cnat_node_ctx_t * ctx);
+
+typedef struct cnat_src_policy_main_
+{
+  cnat_vip_source_policy_t vip_policy;
+  cnat_vip_source_policy_t default_policy;
+
+  /* Per proto source ports allocator for snat */
+  cnat_src_port_allocator_t *src_ports;
+} cnat_src_policy_main_t;
+
+extern cnat_src_policy_main_t cnat_src_policy_main;
+
+void cnat_register_vip_src_policy (cnat_vip_source_policy_t fp);
+int cnat_allocate_port (u16 * port, ip_protocol_t iproto);
+void cnat_free_port (u16 port, ip_protocol_t iproto);
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
+
+#endif