nat: refactor mss_clamping to not depend on snat_main_t

Type: refactor
Signed-off-by: Ole Troan <ot@cisco.com>
Change-Id: I1110e425859a4f1f07952c91b50f263cb7323836

diff --git a/src/plugins/nat/in2out.c b/src/plugins/nat/in2out.c
index a448867..980a638 100644 (file)
--- a/src/plugins/nat/in2out.c
+++ b/src/plugins/nat/in2out.c
@@ -35,6 +35,7 @@
 #include <vppinfra/hash.h>
 #include <vppinfra/error.h>
 #include <vppinfra/elog.h>
+#include <nat/lib/nat_inlines.h>
 
 typedef struct
 {
@@ -1109,7 +1110,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
                  sum0 = ip_csum_update (sum0, old_port0, new_port0,
                                         ip4_header_t /* cheat */ ,
                                         length /* changed member */ );
-                 mss_clamping (sm, tcp0, &sum0);
+                 mss_clamping (sm->mss_clamping, tcp0, &sum0);
                  tcp0->checksum = ip_csum_fold (sum0);
                }
              tcp_packets++;
@@ -1317,7 +1318,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
                  sum1 = ip_csum_update (sum1, old_port1, new_port1,
                                         ip4_header_t /* cheat */ ,
                                         length /* changed member */ );
-                 mss_clamping (sm, tcp1, &sum1);
+                 mss_clamping (sm->mss_clamping, tcp1, &sum1);
                  tcp1->checksum = ip_csum_fold (sum1);
                }
              tcp_packets++;
@@ -1560,7 +1561,7 @@ snat_in2out_node_fn_inline (vlib_main_t * vm,
                  sum0 = ip_csum_update (sum0, old_port0, new_port0,
                                         ip4_header_t /* cheat */ ,
                                         length /* changed member */ );
-                 mss_clamping (sm, tcp0, &sum0);
+                 mss_clamping (sm->mss_clamping, tcp0, &sum0);
                  tcp0->checksum = ip_csum_fold (sum0);
                }
              tcp_packets++;
@@ -1885,7 +1886,7 @@ VLIB_NODE_FN (snat_in2out_fast_node) (vlib_main_t * vm,
                  sum0 = ip_csum_update (sum0, old_port0, new_port0,
                                         ip4_header_t /* cheat */ ,
                                         length /* changed member */ );
-                 mss_clamping (sm, tcp0, &sum0);
+                 mss_clamping (sm->mss_clamping, tcp0, &sum0);
                  tcp0->checksum = ip_csum_fold (sum0);
                }
              else if (udp0->checksum)
@@ -1908,7 +1909,7 @@ VLIB_NODE_FN (snat_in2out_fast_node) (vlib_main_t * vm,
                  sum0 = ip_csum_update (sum0, old_addr0, new_addr0,
                                         ip4_header_t,
                                         dst_address /* changed member */ );
-                 mss_clamping (sm, tcp0, &sum0);
+                 mss_clamping (sm->mss_clamping, tcp0, &sum0);
                  tcp0->checksum = ip_csum_fold (sum0);
                }
              else if (udp0->checksum)

diff --git a/src/plugins/nat/in2out_ed.c b/src/plugins/nat/in2out_ed.c
index 06e6772..9b10d9d 100644 (file)
--- a/src/plugins/nat/in2out_ed.c
+++ b/src/plugins/nat/in2out_ed.c
@@ -32,6 +32,7 @@
 #include <nat/nat_syslog.h>
 #include <nat/nat_ha.h>
 #include <nat/nat44/ed_inlines.h>
+#include <nat/lib/nat_inlines.h>
 
 static char *nat_in2out_ed_error_strings[] = {
 #define _(sym,string) string,
@@ -1096,7 +1097,7 @@ nat44_ed_in2out_fast_path_node_fn_inline (vlib_main_t * vm,
                      tcp0->dst_port = s0->ext_host_port;
                      ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
                    }
-                 mss_clamping (sm, tcp0, &sum0);
+                 mss_clamping (sm->mss_clamping, tcp0, &sum0);
                  tcp0->checksum = ip_csum_fold (sum0);
                }
              tcp_packets++;
@@ -1406,7 +1407,7 @@ nat44_ed_in2out_slow_path_node_fn_inline (vlib_main_t * vm,
                      tcp0->dst_port = s0->ext_host_port;
                      ip0->dst_address.as_u32 = s0->ext_host_addr.as_u32;
                    }
-                 mss_clamping (sm, tcp0, &sum0);
+                 mss_clamping (sm->mss_clamping, tcp0, &sum0);
                  tcp0->checksum = ip_csum_fold (sum0);
                }
              tcp_packets++;

diff --git a/src/plugins/nat/lib/nat_inlines.h b/src/plugins/nat/lib/nat_inlines.h
new file mode 100644 (file)
index 0000000..fc8e160
--- /dev/null
+++ b/src/plugins/nat/lib/nat_inlines.h
@@ -0,0 +1,66 @@
+/*
+ * 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 <vnet/tcp/tcp_packet.h>
+#include <vnet/ip/ip4_packet.h>
+
+always_inline void
+mss_clamping (u16 mss_clamping, tcp_header_t * tcp, ip_csum_t * sum)
+{
+  u8 *data;
+  u8 opt_len, opts_len, kind;
+  u16 mss;
+
+  if (!(mss_clamping && tcp_syn (tcp)))
+    return;
+
+  opts_len = (tcp_doff (tcp) << 2) - sizeof (tcp_header_t);
+  data = (u8 *) (tcp + 1);
+  for (; opts_len > 0; opts_len -= opt_len, data += opt_len)
+    {
+      kind = data[0];
+
+      if (kind == TCP_OPTION_EOL)
+       break;
+      else if (kind == TCP_OPTION_NOOP)
+       {
+         opt_len = 1;
+         continue;
+       }
+      else
+       {
+         if (opts_len < 2)
+           return;
+         opt_len = data[1];
+
+         if (opt_len < 2 || opt_len > opts_len)
+           return;
+       }
+
+      if (kind == TCP_OPTION_MSS)
+       {
+         mss = *(u16 *) (data + 2);
+         if (clib_net_to_host_u16 (mss) > mss_clamping)
+           {
+             u16 mss_value_net = clib_host_to_net_u16(mss_clamping);
+             *sum =
+               ip_csum_update (*sum, mss, mss_value_net, ip4_header_t,
+                               length);
+             clib_memcpy_fast (data + 2, &mss_value_net, 2);
+           }
+         return;
+       }
+    }
+}

diff --git a/src/plugins/nat/nat.h b/src/plugins/nat/nat.h
index 8ec0c62..de23538 100644 (file)
--- a/src/plugins/nat/nat.h
+++ b/src/plugins/nat/nat.h
@@ -654,7 +654,6 @@ typedef struct snat_main_s
 
   /* TCP MSS clamping */
   u16 mss_clamping;
-  u16 mss_value_net;
 
   /* counters/gauges */
   vlib_simple_counter_main_t total_users;

diff --git a/src/plugins/nat/nat44_cli.c b/src/plugins/nat/nat44_cli.c
index ccc2eac..9e9751d 100644 (file)
--- a/src/plugins/nat/nat44_cli.c
+++ b/src/plugins/nat/nat44_cli.c
@@ -358,10 +358,7 @@ nat_set_mss_clamping_command_fn (vlib_main_t * vm, unformat_input_t * input,
       if (unformat (line_input, "disable"))
        sm->mss_clamping = 0;
       else if (unformat (line_input, "%d", &mss))
-       {
-         sm->mss_clamping = (u16) mss;
-         sm->mss_value_net = clib_host_to_net_u16 (sm->mss_clamping);
-       }
+       sm->mss_clamping = (u16) mss;
       else
        {
          error = clib_error_return (0, "unknown input '%U'",

diff --git a/src/plugins/nat/nat64_in2out.c b/src/plugins/nat/nat64_in2out.c
index 38e9834..af212d3 100644 (file)
--- a/src/plugins/nat/nat64_in2out.c
+++ b/src/plugins/nat/nat64_in2out.c
@@ -21,6 +21,7 @@
 #include <nat/nat_inlines.h>
 #include <vnet/ip/ip6_to_ip4.h>
 #include <vnet/fib/fib_table.h>
+#include <nat/lib/nat_inlines.h>
 
 typedef struct
 {
@@ -276,7 +277,7 @@ nat64_in2out_tcp_udp (vlib_main_t * vm, vlib_buffer_t * p, u16 l4_offset,
          csum = ip_csum_add_even (csum, ip4->src_address.as_u32);
          csum = ip_csum_sub_even (csum, sport);
          csum = ip_csum_add_even (csum, udp->src_port);
-         mss_clamping (nm->sm, tcp, &csum);
+         mss_clamping (nm->sm->mss_clamping, tcp, &csum);
          tcp->checksum = ip_csum_fold (csum);
 
          nat64_tcp_session_set_state (ste, tcp, 1);

diff --git a/src/plugins/nat/nat_api.c b/src/plugins/nat/nat_api.c
index 201c9d4..abd1d86 100644 (file)
--- a/src/plugins/nat/nat_api.c
+++ b/src/plugins/nat/nat_api.c
@@ -495,10 +495,7 @@ vl_api_nat_set_mss_clamping_t_handler (vl_api_nat_set_mss_clamping_t * mp)
   int rv = 0;
 
   if (mp->enable)
-    {
-      sm->mss_clamping = ntohs (mp->mss_value);
-      sm->mss_value_net = mp->mss_value;
-    }
+    sm->mss_clamping = ntohs (mp->mss_value);
   else
     sm->mss_clamping = 0;
 

diff --git a/src/plugins/nat/nat_det_in2out.c b/src/plugins/nat/nat_det_in2out.c
index cf50805..8628fcc 100644 (file)
--- a/src/plugins/nat/nat_det_in2out.c
+++ b/src/plugins/nat/nat_det_in2out.c
@@ -26,6 +26,7 @@
 #include <nat/nat.h>
 #include <nat/nat_det.h>
 #include <nat/nat_inlines.h>
+#include <nat/lib/nat_inlines.h>
 
 typedef struct
 {
@@ -438,7 +439,7 @@ VLIB_NODE_FN (snat_det_in2out_node) (vlib_main_t * vm,
              sum0 = ip_csum_update (sum0, old_port0, new_port0,
                                     ip4_header_t /* cheat */ ,
                                     length /* changed member */ );
-             mss_clamping (sm, tcp0, &sum0);
+             mss_clamping (sm->mss_clamping, tcp0, &sum0);
              tcp0->checksum = ip_csum_fold (sum0);
            }
          else
@@ -611,7 +612,7 @@ VLIB_NODE_FN (snat_det_in2out_node) (vlib_main_t * vm,
              sum1 = ip_csum_update (sum1, old_port1, new_port1,
                                     ip4_header_t /* cheat */ ,
                                     length /* changed member */ );
-             mss_clamping (sm, tcp1, &sum1);
+             mss_clamping (sm->mss_clamping, tcp1, &sum1);
              tcp1->checksum = ip_csum_fold (sum1);
            }
          else
@@ -820,7 +821,7 @@ VLIB_NODE_FN (snat_det_in2out_node) (vlib_main_t * vm,
              sum0 = ip_csum_update (sum0, old_port0, new_port0,
                                     ip4_header_t /* cheat */ ,
                                     length /* changed member */ );
-             mss_clamping (sm, tcp0, &sum0);
+             mss_clamping (sm->mss_clamping, tcp0, &sum0);
              tcp0->checksum = ip_csum_fold (sum0);
            }
          else

diff --git a/src/plugins/nat/nat_inlines.h b/src/plugins/nat/nat_inlines.h
index 121d2c7..4dad11b 100644 (file)
--- a/src/plugins/nat/nat_inlines.h
+++ b/src/plugins/nat/nat_inlines.h
@@ -657,54 +657,6 @@ get_icmp_o2i_ed_key (vlib_buffer_t * b, ip4_header_t * ip0, u32 rx_fib_index,
   return 0;
 }
 
-always_inline void
-mss_clamping (snat_main_t * sm, tcp_header_t * tcp, ip_csum_t * sum)
-{
-  u8 *data;
-  u8 opt_len, opts_len, kind;
-  u16 mss;
-
-  if (!(sm->mss_clamping && tcp_syn (tcp)))
-    return;
-
-  opts_len = (tcp_doff (tcp) << 2) - sizeof (tcp_header_t);
-  data = (u8 *) (tcp + 1);
-  for (; opts_len > 0; opts_len -= opt_len, data += opt_len)
-    {
-      kind = data[0];
-
-      if (kind == TCP_OPTION_EOL)
-       break;
-      else if (kind == TCP_OPTION_NOOP)
-       {
-         opt_len = 1;
-         continue;
-       }
-      else
-       {
-         if (opts_len < 2)
-           return;
-         opt_len = data[1];
-
-         if (opt_len < 2 || opt_len > opts_len)
-           return;
-       }
-
-      if (kind == TCP_OPTION_MSS)
-       {
-         mss = *(u16 *) (data + 2);
-         if (clib_net_to_host_u16 (mss) > sm->mss_clamping)
-           {
-             *sum =
-               ip_csum_update (*sum, mss, sm->mss_value_net, ip4_header_t,
-                               length);
-             clib_memcpy_fast (data + 2, &sm->mss_value_net, 2);
-           }
-         return;
-       }
-    }
-}
-
 /**
  * @brief Check if packet should be translated
  *