From 644cf51c8eaeedb4f45642ad85b60f1ee44d9a8a Mon Sep 17 00:00:00 2001
From: Vladimir Zhigulin <vladimir.jigulin@travelping.com>
Date: Fri, 9 Feb 2024 01:51:51 +0100
Subject: [PATCH] do not send ipfix record without port

---
 upf/upf.h          |  1 +
 upf/upf_classify.c |  8 ++++----
 upf/upf_forward.c  |  6 +-----
 upf/upf_ipfix.c    |  3 +++
 upf/upf_pfcp_api.c | 10 +++-------
 5 files changed, 12 insertions(+), 16 deletions(-)

diff --git a/upf/upf.h b/upf/upf.h
index 5ceaf56..1196d40 100644
--- a/upf/upf.h
+++ b/upf/upf.h
@@ -481,6 +481,7 @@ typedef struct
 #define FAR_BUFFER    0x0004
 #define FAR_NOTIFY_CP 0x0008
 #define FAR_DUPLICATE 0x0010
+#define FAR_NAT       0x8000
 
   union
   {
diff --git a/upf/upf_classify.c b/upf/upf_classify.c
index 3f92a92..dd2227a 100644
--- a/upf/upf_classify.c
+++ b/upf/upf_classify.c
@@ -428,15 +428,16 @@ upf_acl_classify_return (vlib_main_t *vm, u32 teid, flow_entry_t *flow,
   return next;
 }
 
-// returns direction which has upload direction
+// returns uplink traffic direction, or FLOW_ENTRY_UPLINK_DIRECTION_UNDEFINED
+// if impossible to detect
 always_inline flow_direction_t
 upf_classify_detect_flow_direction (vlib_buffer_t *b, struct rules *r,
                                     flow_direction_t direction, bool *found)
 {
   // Here we rely on the fact that interface of type ACCESS is one which
   // directed to UE
-  // TODO: it should be possible save this value per PDR since it has this
-  // values available
+  // TODO: it should be possible to calculate and save this value per PDR
+  // during session creation/modification
 
   *found = false;
 
@@ -584,7 +585,6 @@ upf_classify_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
               next = upf_acl_classify_forward (
                 vm, upf_buffer_opaque (b)->gtpu.teid, flow, active, is_ip4,
                 &upf_buffer_opaque (b)->gtpu.pdr_idx);
-
               if (reclassify_proxy_flow) /* for app detection */
                 {
                   if (upf_buffer_opaque (b)->gtpu.is_proxied)
diff --git a/upf/upf_forward.c b/upf/upf_forward.c
index 2499532..3a70f2b 100644
--- a/upf/upf_forward.c
+++ b/upf/upf_forward.c
@@ -230,11 +230,7 @@ upf_forward (vlib_main_t *vm, vlib_node_runtime_t *node, const char *node_name,
                         &vnet_buffer (b)->sw_if_index[VLIB_RX],
                         &vnet_buffer (b)->sw_if_index[VLIB_TX]);
                     }
-                  vnet_buffer (b)->sw_if_index[VLIB_TX] =
-                    (upf_main.nwis + far->forward.nwi_index)
-                      ->fib_index[is_ip4 ? FIB_PROTOCOL_IP4 :
-                                           FIB_PROTOCOL_IP6];
-                  next = UPF_FORWARD_NEXT_IP_LOOKUP;
+                  next = UPF_FORWARD_NEXT_IP_INPUT;
 
                   /*
                    * Forwarding Policy can override the normal FAR processing
diff --git a/upf/upf_ipfix.c b/upf/upf_ipfix.c
index 536feba..1527083 100644
--- a/upf/upf_ipfix.c
+++ b/upf/upf_ipfix.c
@@ -435,6 +435,9 @@ upf_ipfix_flow_init (flow_entry_t *f)
   if (!up_far)
     return false;
 
+  if (up_far->apply_action & FAR_NAT && f->nat_sport == 0)
+    return false;
+
   if (pool_is_free_index (gtm->nwis, up_far->forward.nwi_index))
     return false;
 
diff --git a/upf/upf_pfcp_api.c b/upf/upf_pfcp_api.c
index 161c11a..95c78a3 100644
--- a/upf/upf_pfcp_api.c
+++ b/upf/upf_pfcp_api.c
@@ -1494,6 +1494,7 @@ handle_create_far (upf_session_t *sx, pfcp_ie_create_far_t *create_far,
                 vec_dup (far->forwarding_parameters.nat_port_block);
               rc = handle_nat_binding_creation (sx, pool_name, response);
               vec_free (pool_name);
+              create->apply_action |= FAR_NAT;
               if (rc)
                 {
                   far_error (response, far,
@@ -1571,14 +1572,9 @@ handle_create_far (upf_session_t *sx, pfcp_ie_create_far_t *create_far,
         }
 
       if (ISSET_BIT (far->grp.fields, CREATE_FAR_TP_IPFIX_POLICY))
-        {
-          create->ipfix_policy =
-            upf_ipfix_lookup_policy (far->ipfix_policy, 0);
-        }
+        create->ipfix_policy = upf_ipfix_lookup_policy (far->ipfix_policy, 0);
       else
-        {
-          create->ipfix_policy = UPF_IPFIX_POLICY_UNSPECIFIED;
-        }
+        create->ipfix_policy = UPF_IPFIX_POLICY_UNSPECIFIED;
     }
 
   pfcp_sort_fars (rules);