Add naive SDAP classifier

openair2/LAYER2/nr_pdcp/nr_pdcp_oai_api.c

@@ -1194,6 +1194,12 @@ void nr_pdcp_release_drb(ue_id_t ue_id, int drb_id)
     drb->delete_entity(drb);
     ue->drb[drb_id - 1] = NULL;
     LOG_I(PDCP, "release DRB %d of UE %ld\n", drb_id, ue_id);
+    int sessionId = 1;
+    nr_sdap_entity_t *sdap = nr_sdap_get_entity(ue_id, sessionId); /* default */
+    if (sdap == NULL)
+      LOG_E(PDCP, "no SDAP entity for UE %ld PDU session ID %d\n", ue_id, sessionId);
+    else
+      sdap->has_second_bearer = 0;
   }
   else
     LOG_E(PDCP, "Attempting to release DRB%d but it is not configured\n", drb_id);

openair2/LAYER2/nr_rlc/nr_rlc_entity_tm.c

@@ -78,14 +78,15 @@ static int generate_tx_pdu(nr_rlc_entity_tm_t *entity, char *buffer, int size)
   entity->tx_size -= sdu->size;
   entity->common.stats.txpdu_pkts++;
   entity->common.stats.txpdu_bytes += size;
-
-  /* No need to 'zero' time-of-arrival; 
-  Segmented packets do need to be duplicated in time-sensitive use cases */
-  if (entity->common.avg_time_is_on) {
+/*
+  if (sdu->sdu->time_of_arrival) {
     uint64_t time_now = time_average_now();
     uint64_t waited_time = time_now - sdu->sdu->time_of_arrival;
+    // set time_of_arrival to 0 so as to update stats only once 
+    sdu->sdu->time_of_arrival = 0;
     time_average_add(entity->common.txsdu_avg_time_to_tx, time_now, waited_time);
   }
+*/
 
   /* update buffer status */
   entity->common.bstatus.tx_size -= sdu->size;

openair2/LAYER2/nr_rlc/nr_rlc_entity_um.c

@@ -521,13 +521,15 @@ static int generate_tx_pdu(nr_rlc_entity_um_t *entity, char *buffer, int size)
   entity->common.stats.txpdu_pkts++;
   entity->common.stats.txpdu_bytes += size;
 
-  /* No need to 'zero' time-of-arrival; 
-  Segmented packets do need to be duplicated in time-sensitive use cases */
-  if (entity->common.avg_time_is_on) {
+  /*
+  if (sdu->sdu->time_of_arrival) {
     uint64_t time_now = time_average_now();
     uint64_t waited_time = time_now - sdu->sdu->time_of_arrival;
+    // set time_of_arrival to 0 so as to update stats only once 
+    sdu->sdu->time_of_arrival = 0;
     time_average_add(entity->common.txsdu_avg_time_to_tx, time_now, waited_time);
   }
+*/
 
   nr_rlc_free_sdu_segment(sdu);
 

openair2/SDAP/nr_sdap/nr_sdap_entity.c

@@ -25,6 +25,13 @@
 #include <openair3/ocp-gtpu/gtp_itf.h>
 #include "openair2/LAYER2/nr_pdcp/nr_pdcp_ue_manager.h"
 
+#include <arpa/inet.h>
+#include <netinet/ip.h>
+#include <netinet/ip6.h>
+#include <netinet/tcp.h>
+#include <netinet/udp.h>
+#include <netinet/ip_icmp.h>
+
 #include <stdlib.h>
 #include <string.h>
 #include <pthread.h>
@@ -56,6 +63,50 @@ void nr_pdcp_submit_sdap_ctrl_pdu(ue_id_t ue_id, rb_id_t sdap_ctrl_pdu_drb, nr_s
   return;
 }
 
+/* \brief returns 1 for packets matching criteria, otherwise 1. Criteria is:
+ *   - TCP packet AND dport != 10101 AND dport != 5201 AND second bearer
+ *   - UDP packet AND dport != 10101 AND dport != 5201 AND dport != 2153 AND dport != 2153 AND second bearer
+ *   - ICMP
+ */
+static int analyze_packet_inc(nr_sdap_entity_t *entity, const unsigned char *sdu_buffer)
+{
+  // mir
+  // Naive L4/L3 packet classifier
+  struct iphdr* hdr = (struct iphdr*)sdu_buffer;
+
+  if(hdr->protocol == IPPROTO_TCP){
+    struct tcphdr* tcp = (struct tcphdr*)((uint32_t*)hdr + hdr->ihl);
+    //uint16_t const src_port = ntohs(tcp->source);
+    uint16_t const dst_port = ntohs(tcp->dest);
+    //printf("TCP pkt src_port %d dst_port %d \n", src_port, dst_port);
+
+    if (entity->is_gnb && entity->has_second_bearer && dst_port != 10101 && dst_port != 5201) {
+      return 1;
+    }
+    //printf("TCP\n");
+  } else if(hdr->protocol == IPPROTO_UDP){
+      struct udphdr *udp = (struct udphdr *)((uint32_t*)hdr + hdr->ihl);
+      //uint16_t const src_port = ntohs(udp->source);
+      uint16_t const dst_port = ntohs(udp->dest);
+      //printf("UDP pkt src_port %d dst_port %d \n", src_port, dst_port);
+    if (entity->is_gnb && entity->has_second_bearer && dst_port != 10101 && dst_port != 5201 && dst_port != 2154 && dst_port != 2153) {
+      return 1;
+    }
+
+  } else if(hdr->protocol == IPPROTO_ICMP){
+    //printf("Ping packet detected \n");
+    if (entity->is_gnb && entity->has_second_bearer) {
+      return 1;
+    }
+    //printf("ping\n");
+    //cnt++;
+  } else {
+    printf("undetected header\n");
+  }
+
+  return 0;
+}
+
 static bool nr_sdap_tx_entity(nr_sdap_entity_t *entity,
                               protocol_ctxt_t *ctxt_p,
                               const srb_flag_t srb_flag,
@@ -91,7 +142,9 @@ static bool nr_sdap_tx_entity(nr_sdap_entity_t *entity,
   }
 
   if(!pdcp_ent_has_sdap){
-    LOG_D(SDAP, "TX - DRB ID: %ld does not have SDAP\n", entity->qfi2drb_table[qfi].drb_id);
+    LOG_W(SDAP, "TX - DRB ID: %ld does not have SDAP\n", entity->qfi2drb_table[qfi].drb_id);
+
+    sdap_drb_id += analyze_packet_inc(entity, sdu_buffer);
     ret = nr_pdcp_data_req_drb(ctxt_p,
                                srb_flag,
                                sdap_drb_id,
@@ -103,6 +156,7 @@ static bool nr_sdap_tx_entity(nr_sdap_entity_t *entity,
                                sourceL2Id,
                                destinationL2Id);
 
+
     if(!ret)
       LOG_E(SDAP, "%s:%d:%s: PDCP refused PDU\n", __FILE__, __LINE__, __FUNCTION__);
 
@@ -114,6 +168,8 @@ static bool nr_sdap_tx_entity(nr_sdap_entity_t *entity,
     return 0;
   }
 
+  sdap_drb_id += analyze_packet_inc(entity, sdu_buffer);
+
   if(ctxt_p->enb_flag) { // gNB
     offset = SDAP_HDR_LENGTH;
     /*
@@ -415,11 +471,12 @@ nr_sdap_entity_t *new_nr_sdap_entity(int is_gnb,
                                      uint8_t mappedQFIs2AddCount)
 {
   if (nr_sdap_get_entity(ue_id, pdusession_id)) {
-    LOG_E(SDAP, "SDAP Entity for UE already exists with RNTI/UE ID: %lu and PDU SESSION ID: %d\n", ue_id, pdusession_id);
+    LOG_I(SDAP, "SDAP Entity for UE already exists with RNTI/UE ID: %lu and PDU SESSION ID: %d\n", ue_id, pdusession_id);
     nr_sdap_entity_t *existing_sdap_entity = nr_sdap_get_entity(ue_id, pdusession_id);
     rb_id_t pdcp_entity = existing_sdap_entity->default_drb;
     if(!is_gnb)
       nr_sdap_ue_qfi2drb_config(existing_sdap_entity, pdcp_entity, ue_id, mapped_qfi_2_add, mappedQFIs2AddCount, drb_identity, has_sdap_rx, has_sdap_tx);
+    existing_sdap_entity->has_second_bearer = 1;
     return existing_sdap_entity;
   }
 
@@ -433,6 +490,7 @@ nr_sdap_entity_t *new_nr_sdap_entity(int is_gnb,
 
   sdap_entity->ue_id = ue_id;
   sdap_entity->pdusession_id = pdusession_id;
+  sdap_entity->is_gnb = is_gnb;
 
   sdap_entity->tx_entity = nr_sdap_tx_entity;
   sdap_entity->rx_entity = nr_sdap_rx_entity;

openair2/SDAP/nr_sdap/nr_sdap_entity.h

@@ -79,6 +79,8 @@ void nr_pdcp_submit_sdap_ctrl_pdu(ue_id_t ue_id, rb_id_t sdap_ctrl_pdu_drb, nr_s
 typedef struct nr_sdap_entity_s {
   ue_id_t ue_id;
   rb_id_t default_drb;
+  int is_gnb;
+  int has_second_bearer;
   int pdusession_id;
   qfi2drb_t qfi2drb_table[SDAP_MAX_QFI];