NAT: Rename snat plugin to nat (VPP-955)

Change-Id: I30a7e3da7a4efc6038a91e27b48045d4b07e2764
Signed-off-by: Matus Fabian <matfabia@cisco.com>

1 files changed, 541 insertions, 0 deletions

diff --git a/src/plugins/nat/nat.h b/src/plugins/nat/nat.h
new file mode 100644
index 00000000000..04c466dc6f5
--- /dev/null
+++ b/src/plugins/nat/nat.h
@@ -0,0 +1,541 @@
+
+/*
+ * nat.h - NAT plugin definitions
+ *
+ * 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.
+ */
+#ifndef __included_nat_h__
+#define __included_nat_h__
+
+#include <vnet/vnet.h>
+#include <vnet/ip/ip.h>
+#include <vnet/ethernet/ethernet.h>
+#include <vnet/ip/icmp46_packet.h>
+#include <vnet/api_errno.h>
+#include <vppinfra/bihash_8_8.h>
+#include <vppinfra/bihash_16_8.h>
+#include <vppinfra/dlist.h>
+#include <vppinfra/error.h>
+#include <vlibapi/api.h>
+
+
+#define SNAT_UDP_TIMEOUT 300
+#define SNAT_UDP_TIMEOUT_MIN 120
+#define SNAT_TCP_TRANSITORY_TIMEOUT 240
+#define SNAT_TCP_ESTABLISHED_TIMEOUT 7440
+#define SNAT_TCP_INCOMING_SYN 6
+#define SNAT_ICMP_TIMEOUT 60
+
+#define SNAT_FLAG_HAIRPINNING (1 << 0)
+
+/* Key */
+typedef struct {
+  union
+  {
+    struct
+    {
+      ip4_address_t addr;
+      u16 port;
+      u16 protocol:3,
+        fib_index:13;
+    };
+    u64 as_u64;
+  };
+} snat_session_key_t;
+
+typedef struct {
+  union
+  {
+    struct
+    {
+      ip4_address_t l_addr;
+      ip4_address_t r_addr;
+      u32 fib_index;
+      u8 proto;
+      u8 rsvd[3];
+    };
+    u64 as_u64[2];
+  };
+} snat_unk_proto_ses_key_t;
+
+typedef struct {
+  union
+  {
+    struct
+    {
+      ip4_address_t ext_host_addr;
+      u16 ext_host_port;
+      u16 out_port;
+    };
+    u64 as_u64;
+  };
+} snat_det_out_key_t;
+
+typedef struct {
+  union
+  {
+    struct
+    {
+      ip4_address_t addr;
+      u32 fib_index;
+    };
+    u64 as_u64;
+  };
+} snat_user_key_t;
+
+typedef struct {
+  union
+  {
+    struct
+    {
+      ip4_address_t addr;
+      u16 port;
+      u16 fib_index;
+    };
+    u64 as_u64;
+  };
+} snat_worker_key_t;
+
+
+#define foreach_snat_protocol \
+  _(UDP, 0, udp, "udp")       \
+  _(TCP, 1, tcp, "tcp")       \
+  _(ICMP, 2, icmp, "icmp")
+
+typedef enum {
+#define _(N, i, n, s) SNAT_PROTOCOL_##N = i,
+  foreach_snat_protocol
+#undef _
+} snat_protocol_t;
+
+
+#define foreach_snat_session_state          \
+  _(0, UNKNOWN, "unknown")                 \
+  _(1, UDP_ACTIVE, "udp-active")           \
+  _(2, TCP_SYN_SENT, "tcp-syn-sent")       \
+  _(3, TCP_ESTABLISHED, "tcp-established") \
+  _(4, TCP_FIN_WAIT, "tcp-fin-wait")       \
+  _(5, TCP_CLOSE_WAIT, "tcp-close-wait")   \
+  _(6, TCP_LAST_ACK, "tcp-last-ack")       \
+  _(7, ICMP_ACTIVE, "icmp-active")
+
+typedef enum {
+#define _(v, N, s) SNAT_SESSION_##N = v,
+  foreach_snat_session_state
+#undef _
+} snat_session_state_t;
+
+
+#define SNAT_SESSION_FLAG_STATIC_MAPPING 1
+#define SNAT_SESSION_FLAG_UNKNOWN_PROTO  2
+
+typedef CLIB_PACKED(struct {
+  snat_session_key_t out2in;    /* 0-15 */
+
+  snat_session_key_t in2out;    /* 16-31 */
+
+  u32 flags;                    /* 32-35 */
+
+  /* per-user translations */
+  u32 per_user_index;           /* 36-39 */
+
+  u32 per_user_list_head_index; /* 40-43 */
+
+  /* Last heard timer */
+  f64 last_heard;               /* 44-51 */
+
+  u64 total_bytes;              /* 52-59 */
+
+  u32 total_pkts;               /* 60-63 */
+
+  /* Outside address */
+  u32 outside_address_index;    /* 64-67 */
+
+  /* External host address */
+  ip4_address_t ext_host_addr;  /* 68-71 */
+
+}) snat_session_t;
+
+
+typedef struct {
+  ip4_address_t addr;
+  u32 fib_index;
+  u32 sessions_per_user_list_head_index;
+  u32 nsessions;
+  u32 nstaticsessions;
+} snat_user_t;
+
+typedef struct {
+  ip4_address_t addr;
+  u32 fib_index;
+#define _(N, i, n, s) \
+  u32 busy_##n##_ports; \
+  uword * busy_##n##_port_bitmap;
+  foreach_snat_protocol
+#undef _
+} snat_address_t;
+
+typedef struct {
+  u16 in_port;
+  snat_det_out_key_t out;
+  u8 state;
+  u32 expire;
+} snat_det_session_t;
+
+typedef struct {
+  ip4_address_t in_addr;
+  u8 in_plen;
+  ip4_address_t out_addr;
+  u8 out_plen;
+  u32 sharing_ratio;
+  u16 ports_per_host;
+  u32 ses_num;
+  /* vector of sessions */
+  snat_det_session_t * sessions;
+} snat_det_map_t;
+
+typedef struct {
+  ip4_address_t local_addr;
+  ip4_address_t external_addr;
+  u16 local_port;
+  u16 external_port;
+  u8 addr_only;
+  u32 vrf_id;
+  u32 fib_index;
+  snat_protocol_t proto;
+} snat_static_mapping_t;
+
+typedef struct {
+  u32 sw_if_index;
+  u8 is_inside;
+} snat_interface_t;
+
+typedef struct {
+  ip4_address_t l_addr;
+  u16 l_port;
+  u16 e_port;
+  u32 sw_if_index;
+  u32 vrf_id;
+  snat_protocol_t proto;
+  int addr_only;
+  int is_add;
+} snat_static_map_resolve_t;
+
+typedef struct {
+  /* User pool */
+  snat_user_t * users;
+
+  /* Session pool */
+  snat_session_t * sessions;
+
+  /* Pool of doubly-linked list elements */
+  dlist_elt_t * list_pool;
+
+  u32 snat_thread_index;
+} snat_main_per_thread_data_t;
+
+struct snat_main_s;
+
+typedef u32 snat_icmp_match_function_t (struct snat_main_s *sm,
+                                        vlib_node_runtime_t *node,
+                                        u32 thread_index,
+                                        vlib_buffer_t *b0,
+                                        u8 *p_proto,
+                                        snat_session_key_t *p_value,
+                                        u8 *p_dont_translate,
+                                        void *d,
+                                        void *e);
+
+typedef u32 (snat_get_worker_function_t) (ip4_header_t * ip, u32 rx_fib_index);
+
+typedef struct snat_main_s {
+  /* Main lookup tables */
+  clib_bihash_8_8_t out2in;
+  clib_bihash_8_8_t in2out;
+
+  /* Unknown protocol sessions lookup tables */
+  clib_bihash_16_8_t out2in_unk_proto;
+  clib_bihash_16_8_t in2out_unk_proto;
+
+  /* Find-a-user => src address lookup */
+  clib_bihash_8_8_t user_hash;
+
+  /* Non-translated packets worker lookup => src address + VRF */
+  clib_bihash_8_8_t worker_by_in;
+
+  /* Translated packets worker lookup => IP address + port number */
+  clib_bihash_8_8_t worker_by_out;
+
+  snat_icmp_match_function_t * icmp_match_in2out_cb;
+  snat_icmp_match_function_t * icmp_match_out2in_cb;
+
+  u32 num_workers;
+  u32 first_worker_index;
+  u32 next_worker;
+  u32 * workers;
+  snat_get_worker_function_t * worker_in2out_cb;
+  snat_get_worker_function_t * worker_out2in_cb;
+  u16 port_per_thread;
+  u32 num_snat_thread;
+
+  /* Per thread data */
+  snat_main_per_thread_data_t * per_thread_data;
+
+  /* Find a static mapping by local */
+  clib_bihash_8_8_t static_mapping_by_local;
+
+  /* Find a static mapping by external */
+  clib_bihash_8_8_t static_mapping_by_external;
+
+  /* Static mapping pool */
+  snat_static_mapping_t * static_mappings;
+
+  /* Interface pool */
+  snat_interface_t * interfaces;
+  snat_interface_t * output_feature_interfaces;
+
+  /* Vector of outside addresses */
+  snat_address_t * addresses;
+
+  /* sw_if_indices whose intfc addresses should be auto-added */
+  u32 * auto_add_sw_if_indices;
+
+  /* vector of interface address static mappings to resolve. */
+  snat_static_map_resolve_t *to_resolve;
+
+  /* Randomize port allocation order */
+  u32 random_seed;
+
+  /* Worker handoff index */
+  u32 fq_in2out_index;
+  u32 fq_in2out_output_index;
+  u32 fq_out2in_index;
+
+  /* in2out and out2in node index */
+  u32 in2out_node_index;
+  u32 in2out_output_node_index;
+  u32 out2in_node_index;
+
+  /* Deterministic NAT */
+  snat_det_map_t * det_maps;
+
+  /* Config parameters */
+  u8 static_mapping_only;
+  u8 static_mapping_connection_tracking;
+  u8 deterministic;
+  u32 translation_buckets;
+  u32 translation_memory_size;
+  u32 user_buckets;
+  u32 user_memory_size;
+  u32 max_translations_per_user;
+  u32 outside_vrf_id;
+  u32 outside_fib_index;
+  u32 inside_vrf_id;
+  u32 inside_fib_index;
+
+  /* tenant VRF aware address pool activation flag */
+  u8 vrf_mode;
+
+  /* values of various timeouts */
+  u32 udp_timeout;
+  u32 tcp_established_timeout;
+  u32 tcp_transitory_timeout;
+  u32 icmp_timeout;
+
+  /* API message ID base */
+  u16 msg_id_base;
+
+  /* convenience */
+  vlib_main_t * vlib_main;
+  vnet_main_t * vnet_main;
+  ip4_main_t * ip4_main;
+  ip_lookup_main_t * ip4_lookup_main;
+  api_main_t * api_main;
+} snat_main_t;
+
+extern snat_main_t snat_main;
+extern vlib_node_registration_t snat_in2out_node;
+extern vlib_node_registration_t snat_in2out_output_node;
+extern vlib_node_registration_t snat_out2in_node;
+extern vlib_node_registration_t snat_in2out_fast_node;
+extern vlib_node_registration_t snat_out2in_fast_node;
+extern vlib_node_registration_t snat_in2out_worker_handoff_node;
+extern vlib_node_registration_t snat_in2out_output_worker_handoff_node;
+extern vlib_node_registration_t snat_out2in_worker_handoff_node;
+extern vlib_node_registration_t snat_det_in2out_node;
+extern vlib_node_registration_t snat_det_out2in_node;
+extern vlib_node_registration_t snat_hairpin_dst_node;
+extern vlib_node_registration_t snat_hairpin_src_node;
+
+void snat_free_outside_address_and_port (snat_main_t * sm,
+                                         snat_session_key_t * k,
+                                         u32 address_index);
+
+int snat_alloc_outside_address_and_port (snat_main_t * sm,
+                                         u32 fib_index,
+                                         u32 thread_index,
+                                         snat_session_key_t * k,
+                                         u32 * address_indexp);
+
+int snat_static_mapping_match (snat_main_t * sm,
+                               snat_session_key_t match,
+                               snat_session_key_t * mapping,
+                               u8 by_external,
+                               u8 *is_addr_only);
+
+void snat_add_del_addr_to_fib (ip4_address_t * addr,
+                               u8 p_len,
+                               u32 sw_if_index,
+                               int is_add);
+
+format_function_t format_snat_user;
+
+typedef struct {
+  u32 cached_sw_if_index;
+  u32 cached_ip4_address;
+} snat_runtime_t;
+
+/** \brief Check if SNAT session is created from static mapping.
+    @param s SNAT session
+    @return 1 if SNAT session is created from static mapping otherwise 0
+*/
+#define snat_is_session_static(s) s->flags & SNAT_SESSION_FLAG_STATIC_MAPPING
+
+/** \brief Check if SNAT session for unknown protocol.
+    @param s SNAT session
+    @return 1 if SNAT session for unknown protocol otherwise 0
+*/
+#define snat_is_unk_proto_session(s) s->flags & SNAT_SESSION_FLAG_UNKNOWN_PROTO
+
+/*
+ * Why is this here? Because we don't need to touch this layer to
+ * simply reply to an icmp. We need to change id to a unique
+ * value to NAT an echo request/reply.
+ */
+
+typedef struct {
+  u16 identifier;
+  u16 sequence;
+} icmp_echo_header_t;
+
+always_inline u32
+ip_proto_to_snat_proto (u8 ip_proto)
+{
+  u32 snat_proto = ~0;
+
+  snat_proto = (ip_proto == IP_PROTOCOL_UDP) ? SNAT_PROTOCOL_UDP : snat_proto;
+  snat_proto = (ip_proto == IP_PROTOCOL_TCP) ? SNAT_PROTOCOL_TCP : snat_proto;
+  snat_proto = (ip_proto == IP_PROTOCOL_ICMP) ? SNAT_PROTOCOL_ICMP : snat_proto;
+  snat_proto = (ip_proto == IP_PROTOCOL_ICMP6) ? SNAT_PROTOCOL_ICMP : snat_proto;
+
+  return snat_proto;
+}
+
+always_inline u8
+snat_proto_to_ip_proto (snat_protocol_t snat_proto)
+{
+  u8 ip_proto = ~0;
+
+  ip_proto = (snat_proto == SNAT_PROTOCOL_UDP) ? IP_PROTOCOL_UDP : ip_proto;
+  ip_proto = (snat_proto == SNAT_PROTOCOL_TCP) ? IP_PROTOCOL_TCP : ip_proto;
+  ip_proto = (snat_proto == SNAT_PROTOCOL_ICMP) ? IP_PROTOCOL_ICMP : ip_proto;
+
+  return ip_proto;
+}
+
+typedef struct {
+  u16 src_port, dst_port;
+} tcp_udp_header_t;
+
+u32 icmp_match_in2out_fast(snat_main_t *sm, vlib_node_runtime_t *node,
+                           u32 thread_index, vlib_buffer_t *b0, u8 *p_proto,
+                           snat_session_key_t *p_value,
+                           u8 *p_dont_translate, void *d, void *e);
+u32 icmp_match_in2out_slow(snat_main_t *sm, vlib_node_runtime_t *node,
+                           u32 thread_index, vlib_buffer_t *b0, u8 *p_proto,
+                           snat_session_key_t *p_value,
+                           u8 *p_dont_translate, void *d, void *e);
+u32 icmp_match_in2out_det(snat_main_t *sm, vlib_node_runtime_t *node,
+                          u32 thread_index, vlib_buffer_t *b0, u8 *p_proto,
+                          snat_session_key_t *p_value,
+                          u8 *p_dont_translate, void *d, void *e);
+u32 icmp_match_out2in_fast(snat_main_t *sm, vlib_node_runtime_t *node,
+                           u32 thread_index, vlib_buffer_t *b0, u8 *p_proto,
+                           snat_session_key_t *p_value,
+                           u8 *p_dont_translate, void *d, void *e);
+u32 icmp_match_out2in_slow(snat_main_t *sm, vlib_node_runtime_t *node,
+                           u32 thread_index, vlib_buffer_t *b0, u8 *p_proto,
+                           snat_session_key_t *p_value,
+                           u8 *p_dont_translate, void *d, void *e);
+u32 icmp_match_out2in_det(snat_main_t *sm, vlib_node_runtime_t *node,
+                          u32 thread_index, vlib_buffer_t *b0, u8 *p_proto,
+                          snat_session_key_t *p_value,
+                          u8 *p_dont_translate, void *d, void *e);
+void increment_v4_address(ip4_address_t * a);
+void snat_add_address(snat_main_t *sm, ip4_address_t *addr, u32 vrf_id);
+int snat_del_address(snat_main_t *sm, ip4_address_t addr, u8 delete_sm);
+int snat_add_static_mapping(ip4_address_t l_addr, ip4_address_t e_addr,
+                            u16 l_port, u16 e_port, u32 vrf_id, int addr_only,
+                            u32 sw_if_index, snat_protocol_t proto, int is_add);
+clib_error_t * snat_api_init(vlib_main_t * vm, snat_main_t * sm);
+int snat_set_workers (uword * bitmap);
+int snat_interface_add_del(u32 sw_if_index, u8 is_inside, int is_del);
+int snat_interface_add_del_output_feature(u32 sw_if_index, u8 is_inside,
+                                          int is_del);
+int snat_add_interface_address(snat_main_t *sm, u32 sw_if_index, int is_del);
+uword unformat_snat_protocol(unformat_input_t * input, va_list * args);
+u8 * format_snat_protocol(u8 * s, va_list * args);
+
+static_always_inline u8
+icmp_is_error_message (icmp46_header_t * icmp)
+{
+  switch(icmp->type)
+    {
+    case ICMP4_destination_unreachable:
+    case ICMP4_time_exceeded:
+    case ICMP4_parameter_problem:
+    case ICMP4_source_quench:
+    case ICMP4_redirect:
+    case ICMP4_alternate_host_address:
+      return 1;
+    }
+  return 0;
+}
+
+static_always_inline u8
+is_interface_addr(snat_main_t *sm, vlib_node_runtime_t *node, u32 sw_if_index0,
+                  u32 ip4_addr)
+{
+  snat_runtime_t *rt = (snat_runtime_t *) node->runtime_data;
+  ip4_address_t * first_int_addr;
+
+  if (PREDICT_FALSE(rt->cached_sw_if_index != sw_if_index0))
+    {
+      first_int_addr =
+        ip4_interface_first_address (sm->ip4_main, sw_if_index0,
+                                     0 /* just want the address */);
+      rt->cached_sw_if_index = sw_if_index0;
+      if (first_int_addr)
+        rt->cached_ip4_address = first_int_addr->as_u32;
+      else
+        rt->cached_ip4_address = 0;
+    }
+
+  if (PREDICT_FALSE(ip4_addr == rt->cached_ip4_address))
+    return 1;
+  else
+    return 0;
+}
+
+#endif /* __included_nat_h__ */