nat: Final NAT44 EI/ED split patch

This patch achieves complete separation of
endpoint-dependent and endpoint-independent IPv4 NAT
features. Some common stuff is also moved to NAT
library.

Type: refactor

Change-Id: I52468b7e2b5ac28958a2baf8e2ea01787322e801
Signed-off-by: Filip Varga <fivarga@cisco.com>

5 files changed, 380 insertions, 1 deletions

diff --git a/src/plugins/nat/lib/lib.c b/src/plugins/nat/lib/lib.c
new file mode 100644
index 00000000000..d2def2cc480
--- /dev/null
+++ b/src/plugins/nat/lib/lib.c
@@ -0,0 +1,59 @@
+/*
+ * 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.
+ */
+
+#include <nat/lib/lib.h>
+
+uword
+unformat_nat_protocol (unformat_input_t *input, va_list *args)
+{
+  u32 *r = va_arg (*args, u32 *);
+
+  if (0)
+    ;
+#define _(N, i, n, s) else if (unformat (input, s)) *r = NAT_PROTOCOL_##N;
+  foreach_nat_protocol
+#undef _
+    else return 0;
+  return 1;
+}
+
+u8 *
+format_nat_protocol (u8 *s, va_list *args)
+{
+  u32 i = va_arg (*args, u32);
+  u8 *t = 0;
+
+  switch (i)
+    {
+#define _(N, j, n, str)                                                       \
+  case NAT_PROTOCOL_##N:                                                      \
+    t = (u8 *) str;                                                           \
+    break;
+      foreach_nat_protocol
+#undef _
+	default : s = format (s, "unknown");
+      return s;
+    }
+  s = format (s, "%s", t);
+  return s;
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/plugins/nat/lib/lib.h b/src/plugins/nat/lib/lib.h
index 04bad5c74f7..b0b5229b337 100644
--- a/src/plugins/nat/lib/lib.h
+++ b/src/plugins/nat/lib/lib.h
@@ -95,7 +95,52 @@ nat_reset_timeouts (nat_timeouts_t * timeouts)
   timeouts->icmp = NAT_ICMP_TIMEOUT;
 }
 
-// TODO: move common formating definitions here
+static_always_inline u32
+nat_session_get_timeout (nat_timeouts_t *timeouts, nat_protocol_t proto,
+			 u8 state)
+{
+  switch (proto)
+    {
+    case NAT_PROTOCOL_ICMP:
+      return timeouts->icmp;
+    case NAT_PROTOCOL_UDP:
+      return timeouts->udp;
+    case NAT_PROTOCOL_TCP:
+      {
+	if (state)
+	  return timeouts->tcp.transitory;
+	else
+	  return timeouts->tcp.established;
+      }
+    default:
+      return timeouts->udp;
+    }
+  return 0;
+}
+
+static_always_inline u32
+nat_calc_bihash_buckets (u32 n_elts)
+{
+  n_elts = n_elts / 2.5;
+  u64 lower_pow2 = 1;
+  while (lower_pow2 * 2 < n_elts)
+    {
+      lower_pow2 = 2 * lower_pow2;
+    }
+  u64 upper_pow2 = 2 * lower_pow2;
+  if ((upper_pow2 - n_elts) < (n_elts - lower_pow2))
+    {
+      if (upper_pow2 <= UINT32_MAX)
+	{
+	  return upper_pow2;
+	}
+    }
+  return lower_pow2;
+}
+
+u8 *format_nat_protocol (u8 *s, va_list *args);
+
+uword unformat_nat_protocol (unformat_input_t *input, va_list *args);
 
 #endif /* included_nat_lib_h__ */
 /*
diff --git a/src/plugins/nat/lib/log.h b/src/plugins/nat/lib/log.h
new file mode 100644
index 00000000000..26bd93f2589
--- /dev/null
+++ b/src/plugins/nat/lib/log.h
@@ -0,0 +1,214 @@
+/*
+ * 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.
+ */
+/**
+ * @file
+ * @brief NAT port/address allocation lib
+ */
+#ifndef included_nat_log_h__
+#define included_nat_log_h__
+
+#include <vppinfra/elog.h>
+
+#define foreach_nat_log_level                                                 \
+  _ (0x00, LOG_NONE)                                                          \
+  _ (0x01, LOG_ERROR)                                                         \
+  _ (0x02, LOG_WARNING)                                                       \
+  _ (0x03, LOG_NOTICE)                                                        \
+  _ (0x04, LOG_INFO)                                                          \
+  _ (0x05, LOG_DEBUG)
+
+typedef enum nat_log_level_t_
+{
+#define _(n, f) NAT_##f = n,
+  foreach_nat_log_level
+#undef _
+} nat_log_level_t;
+
+#define nat_elog(_pm, _level, _str)                                           \
+  do                                                                          \
+    {                                                                         \
+      if (PREDICT_FALSE (_pm->log_level >= _level))                           \
+	{                                                                     \
+	  ELOG_TYPE_DECLARE (e) = {                                           \
+	    .format = "nat-msg " _str,                                        \
+	    .format_args = "",                                                \
+	  };                                                                  \
+	  ELOG_DATA (&vlib_global_main.elog_main, e);                         \
+	}                                                                     \
+    }                                                                         \
+  while (0);
+
+#define nat_elog_addr(_pm, _level, _str, _addr)                               \
+  do                                                                          \
+    {                                                                         \
+      if (PREDICT_FALSE (_pm->log_level >= _level))                           \
+	{                                                                     \
+	  ELOG_TYPE_DECLARE (e) = {                                           \
+	    .format = "nat-msg " _str " %d.%d.%d.%d",                         \
+	    .format_args = "i1i1i1i1",                                        \
+	  };                                                                  \
+	  CLIB_PACKED (struct {                                               \
+	    u8 oct1;                                                          \
+	    u8 oct2;                                                          \
+	    u8 oct3;                                                          \
+	    u8 oct4;                                                          \
+	  }) *                                                                \
+	    ed;                                                               \
+	  ed = ELOG_DATA (&vlib_global_main.elog_main, e);                    \
+	  ed->oct4 = _addr >> 24;                                             \
+	  ed->oct3 = _addr >> 16;                                             \
+	  ed->oct2 = _addr >> 8;                                              \
+	  ed->oct1 = _addr;                                                   \
+	}                                                                     \
+    }                                                                         \
+  while (0);
+
+#define nat_elog_debug_handoff(_pm, _str, _tid, _fib, _src, _dst)             \
+  do                                                                          \
+    {                                                                         \
+      if (PREDICT_FALSE (_pm->log_level >= NAT_LOG_DEBUG))                    \
+	{                                                                     \
+	  ELOG_TYPE_DECLARE (e) = {                                           \
+	    .format = "nat-msg " _str " ip src: %d.%d.%d.%d dst: %d.%d.%d.%d" \
+		      " tid from: %d to: %d fib: %d",                         \
+	    .format_args = "i1i1i1i1i1i1i1i1i4i4i4",                          \
+	  };                                                                  \
+	  CLIB_PACKED (struct {                                               \
+	    u8 src_oct1;                                                      \
+	    u8 src_oct2;                                                      \
+	    u8 src_oct3;                                                      \
+	    u8 src_oct4;                                                      \
+	    u8 dst_oct1;                                                      \
+	    u8 dst_oct2;                                                      \
+	    u8 dst_oct3;                                                      \
+	    u8 dst_oct4;                                                      \
+	    u32 ftid;                                                         \
+	    u32 ttid;                                                         \
+	    u32 fib;                                                          \
+	  }) *                                                                \
+	    ed;                                                               \
+	  ed = ELOG_DATA (&vlib_global_main.elog_main, e);                    \
+	  ed->src_oct1 = _src >> 24;                                          \
+	  ed->src_oct2 = _src >> 16;                                          \
+	  ed->src_oct3 = _src >> 8;                                           \
+	  ed->src_oct4 = _src;                                                \
+	  ed->dst_oct1 = _dst >> 24;                                          \
+	  ed->dst_oct2 = _dst >> 16;                                          \
+	  ed->dst_oct3 = _dst >> 8;                                           \
+	  ed->dst_oct4 = _dst;                                                \
+	  ed->ftid = vlib_get_thread_index ();                                \
+	  ed->ttid = _tid;                                                    \
+	  ed->fib = _fib;                                                     \
+	}                                                                     \
+    }                                                                         \
+  while (0);
+
+#define nat_elog_debug_handoff_v2(_pm, _str, _prt, _fib, _src, _dst)          \
+  do                                                                          \
+    {                                                                         \
+      if (PREDICT_FALSE (_pm->log_level >= NAT_LOG_DEBUG))                    \
+	{                                                                     \
+	  ELOG_TYPE_DECLARE (e) = {                                           \
+	    .format =                                                         \
+	      "nat-msg " _str " ip_src:%d.%d.%d.%d ip_dst:%d.%d.%d.%d"        \
+	      " tid:%d prt:%d fib:%d",                                        \
+	    .format_args = "i1i1i1i1i1i1i1i1i4i4i4",                          \
+	  };                                                                  \
+	  CLIB_PACKED (struct {                                               \
+	    u8 src_oct1;                                                      \
+	    u8 src_oct2;                                                      \
+	    u8 src_oct3;                                                      \
+	    u8 src_oct4;                                                      \
+	    u8 dst_oct1;                                                      \
+	    u8 dst_oct2;                                                      \
+	    u8 dst_oct3;                                                      \
+	    u8 dst_oct4;                                                      \
+	    u32 tid;                                                          \
+	    u32 prt;                                                          \
+	    u32 fib;                                                          \
+	  }) *                                                                \
+	    ed;                                                               \
+	  ed = ELOG_DATA (&vlib_global_main.elog_main, e);                    \
+	  ed->src_oct1 = _src >> 24;                                          \
+	  ed->src_oct2 = _src >> 16;                                          \
+	  ed->src_oct3 = _src >> 8;                                           \
+	  ed->src_oct4 = _src;                                                \
+	  ed->dst_oct1 = _dst >> 24;                                          \
+	  ed->dst_oct2 = _dst >> 16;                                          \
+	  ed->dst_oct3 = _dst >> 8;                                           \
+	  ed->dst_oct4 = _dst;                                                \
+	  ed->tid = vlib_get_thread_index ();                                 \
+	  ed->prt = _prt;                                                     \
+	  ed->fib = _fib;                                                     \
+	}                                                                     \
+    }                                                                         \
+  while (0);
+
+#define nat_elog_X1(_pm, _level, _fmt, _arg, _val1)                           \
+  do                                                                          \
+    {                                                                         \
+      if (PREDICT_FALSE (_pm->log_level >= _level))                           \
+	{                                                                     \
+	  ELOG_TYPE_DECLARE (e) = {                                           \
+	    .format = "nat-msg " _fmt,                                        \
+	    .format_args = _arg,                                              \
+	  };                                                                  \
+	  CLIB_PACKED (struct { typeof (_val1) val1; }) * ed;                 \
+	  ed = ELOG_DATA (&vlib_global_main.elog_main, e);                    \
+	  ed->val1 = _val1;                                                   \
+	}                                                                     \
+    }                                                                         \
+  while (0);
+
+#define nat_elog_notice(_pm, nat_elog_str)                                    \
+  nat_elog (_pm, NAT_LOG_INFO, "[notice] " nat_elog_str)
+#define nat_elog_warn(_pm, nat_elog_str)                                      \
+  nat_elog (_pm, NAT_LOG_WARNING, "[warning] " nat_elog_str)
+#define nat_elog_err(_pm, nat_elog_str)                                       \
+  nat_elog (_pm, NAT_LOG_ERROR, "[error] " nat_elog_str)
+#define nat_elog_debug(_pm, nat_elog_str)                                     \
+  nat_elog (_pm, NAT_LOG_DEBUG, "[debug] " nat_elog_str)
+#define nat_elog_info(_pm, nat_elog_str)                                      \
+  nat_elog (_pm, NAT_LOG_INFO, "[info] " nat_elog_str)
+
+#define nat_elog_notice_X1(_pm, nat_elog_fmt_str, nat_elog_fmt_arg,           \
+			   nat_elog_val1)                                     \
+  nat_elog_X1 (_pm, NAT_LOG_NOTICE, "[notice] " nat_elog_fmt_str,             \
+	       nat_elog_fmt_arg, nat_elog_val1)
+#define nat_elog_warn_X1(_pm, nat_elog_fmt_str, nat_elog_fmt_arg,             \
+			 nat_elog_val1)                                       \
+  nat_elog_X1 (_pm, NAT_LOG_WARNING, "[warning] " nat_elog_fmt_str,           \
+	       nat_elog_fmt_arg, nat_elog_val1)
+#define nat_elog_err_X1(_pm, nat_elog_fmt_str, nat_elog_fmt_arg,              \
+			nat_elog_val1)                                        \
+  nat_elog_X1 (_pm, NAT_LOG_ERROR, "[error] " nat_elog_fmt_str,               \
+	       nat_elog_fmt_arg, nat_elog_val1)
+#define nat_elog_debug_X1(_pm, nat_elog_fmt_str, nat_elog_fmt_arg,            \
+			  nat_elog_val1)                                      \
+  nat_elog_X1 (_pm, NAT_LOG_DEBUG, "[debug] " nat_elog_fmt_str,               \
+	       nat_elog_fmt_arg, nat_elog_val1)
+#define nat_elog_info_X1(_pm, nat_elog_fmt_str, nat_elog_fmt_arg,             \
+			 nat_elog_val1)                                       \
+  nat_elog_X1 (_pm, NAT_LOG_INFO, "[info] " nat_elog_fmt_str,                 \
+	       nat_elog_fmt_arg, nat_elog_val1)
+
+#endif /* included_nat_lib_h__ */
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/src/plugins/nat/lib/nat_inlines.h b/src/plugins/nat/lib/nat_inlines.h
index c75b8043cc1..0bd7993ac04 100644
--- a/src/plugins/nat/lib/nat_inlines.h
+++ b/src/plugins/nat/lib/nat_inlines.h
@@ -77,6 +77,20 @@ mss_clamping (u16 mss_clamping, tcp_header_t * tcp, ip_csum_t * sum)
     }
 }
 
+static_always_inline u16
+nat_random_port (u32 *random_seed, u16 min, u16 max)
+{
+  u32 rwide;
+  u16 r;
+
+  rwide = random_u32 (random_seed);
+  r = rwide & 0xFFFF;
+  if (r >= min && r <= max)
+    return r;
+
+  return min + (rwide % (max - min + 1));
+}
+
 #endif /* __included_lib_nat_inlines_h__ */
 
 /*
diff --git a/src/plugins/nat/lib/nat_types.api b/src/plugins/nat/lib/nat_types.api
new file mode 100644
index 00000000000..ad4ee9faba0
--- /dev/null
+++ b/src/plugins/nat/lib/nat_types.api
@@ -0,0 +1,47 @@
+/*
+ * 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.
+ */
+
+option version = "0.0.1";
+
+typedef nat_timeouts
+{
+  u32 udp;
+  u32 tcp_established;
+  u32 tcp_transitory;
+  u32 icmp;
+};
+
+enum nat_log_level : u8
+{
+  NAT_LOG_NONE = 0x00,
+  NAT_LOG_ERROR = 0x01,
+  NAT_LOG_WARNING = 0x02,
+  NAT_LOG_NOTICE = 0x03,
+  NAT_LOG_INFO = 0x04,
+  NAT_LOG_DEBUG = 0x05,
+};
+
+enum nat_config_flags : u8
+{
+  NAT_IS_NONE = 0x00,
+  NAT_IS_TWICE_NAT = 0x01,
+  NAT_IS_SELF_TWICE_NAT = 0x02,
+  NAT_IS_OUT2IN_ONLY = 0x04,
+  NAT_IS_ADDR_ONLY = 0x08,
+  NAT_IS_OUTSIDE = 0x10,
+  NAT_IS_INSIDE = 0x20,
+  NAT_IS_STATIC = 0x40,
+  NAT_IS_EXT_HOST_VALID = 0x80,
+};