Update iab_info_management.h

common/config/config_load_configmodule.c

@@ -354,6 +354,7 @@ configmodule_interface_t *load_configmodule(int argc,
 
     if (i ==  0) {
       printf("[CONFIG] config module %s loaded\n",cfgmode);
+      // Continue/Read from this
       int idx = config_paramidx_fromname(Config_Params, sizeofArray(Config_Params), CONFIGP_DEBUGFLAGS);
       Config_Params[idx].uptr = &(cfgptr->rtflags);
       idx = config_paramidx_fromname(Config_Params, sizeofArray(Config_Params), CONFIGP_TMPDIR);

common/config/config_userapi.c

@@ -126,6 +126,12 @@ int config_get(configmodule_interface_t *cfgif, paramdef_t *params, int numparam
 
   if (cfgif != NULL) {
     ret = cfgif->get(cfgif, params, numparams, prefix);
+    /* testing 
+    printf("Num params: %d\n", numparams);
+    for (int i = 0; i < numparams; i++){
+      printf("%d, %s\n", i, params[i].optname);
+    }
+     end testing */
 
     if (ret >= 0) {
       config_process_cmdline(cfgif, params, numparams, prefix);

common/ngran_types.h

@@ -44,14 +44,18 @@ typedef enum {
   ngran_gNB_DU    = 7,
   ngran_eNB_MBMS_STA  = 8,
   ngran_gNB_CUCP  = 9,
-  ngran_gNB_CUUP  = 10
+  ngran_gNB_CUUP  = 10,
+  ngran_gNB_IAB_donor_DU = 11,
+  ngran_gNB_IAB_node_DU = 12,
 } ngran_node_t;
 
 typedef enum { CPtype = 0, UPtype } E1_t;
 
 #define NODE_IS_MONOLITHIC(nOdE_TyPe) ((nOdE_TyPe) == ngran_eNB    || (nOdE_TyPe) == ngran_ng_eNB    || (nOdE_TyPe) == ngran_gNB)
-#define NODE_IS_CU(nOdE_TyPe)         ((nOdE_TyPe) == ngran_eNB_CU || (nOdE_TyPe) == ngran_ng_eNB_CU || (nOdE_TyPe) == ngran_gNB_CU || (nOdE_TyPe) == ngran_gNB_CUCP || (nOdE_TyPe) == ngran_gNB_CUUP)
-#define NODE_IS_DU(nOdE_TyPe)         ((nOdE_TyPe) == ngran_eNB_DU || (nOdE_TyPe) == ngran_gNB_DU)
+#define NODE_IS_CU(nOdE_TyPe)         ((nOdE_TyPe) == ngran_eNB_CU || (nOdE_TyPe) == ngran_ng_eNB_CU || (nOdE_TyPe) == ngran_gNB_CU           || (nOdE_TyPe) == ngran_gNB_CUCP        || (nOdE_TyPe) == ngran_gNB_CUUP)
+#define NODE_IS_DU(nOdE_TyPe)         ((nOdE_TyPe) == ngran_eNB_DU || (nOdE_TyPe) == ngran_gNB_DU    || (nOdE_TyPe) == ngran_gNB_IAB_donor_DU || (nOdE_TyPe) == ngran_gNB_IAB_node_DU)
+#define NODE_IS_IAB_DONOR_DU(nOdE_TyPe)     ((nOdE_TyPe) == ngran_gNB_IAB_donor_DU)
+#define NODE_IS_IAB_NODE_DU(nOdE_TyPe)     ((nOdE_TyPe) == ngran_gNB_IAB_node_DU)
 #define NODE_IS_MBMS(nOdE_TyPe)       ((nOdE_TyPe) == ngran_eNB_MBMS_STA)
 #define GTPV1_U_PORT_NUMBER (2152)
 

common/ran_context.h

@@ -41,6 +41,7 @@ struct PHY_VARS_gNB_s;
 struct PHY_VARS_eNB_NB_IoT_s;
 struct eNB_RRC_INST_s;
 struct gNB_RRC_INST_s;
+struct gNB_IAB_INFO_s;
 struct eNB_MAC_INST_s;
 struct eNB_MAC_INST_NB_IoT_s;
 struct gNB_MAC_INST_s;
@@ -92,6 +93,8 @@ typedef struct {
   //struct eNB_RRC_INST_NB_IoT_s **nb_iot_rrc;
   /// NR RRC context variables
   struct gNB_RRC_INST_s **nrrrc;
+  /// IAB context variables
+  struct gNB_IAB_INFO_s **iab;
   /// MAC context variables
   struct eNB_MAC_INST_s **mac;
   /// NB_IoT MAC context variables

doc/IAB_docs/BAP_Info.md

@@ -0,0 +1,356 @@
+<table style="border-collapse: collapse; border: none;">
+  <tr style="border-collapse: collapse; border: none;">
+    <td style="border-collapse: collapse; border: none;">
+      <a href="http://www.openairinterface.org/">
+         <img src="../images/oai_final_logo.png" alt="" border=3 height=50 width=150>
+         </img>
+      </a>
+    </td>
+    <td style="border-collapse: collapse; border: none; vertical-align: center;">
+      <b><font size = "5">BAP Documentation</font></b>
+    </td>
+  </tr>
+</table>
+
+**Table of Contents**
+
+[[_TOC_]]
+
+# Glossary
+
+| Acronym | Description                    |
+| ------- | ------------------------------ |
+| BAP     | Backhaul Adaptation Protocol   |
+| BH      | Backhaul                       |
+| CU      | Centralized Unit               |
+| DU      | Distributed Unit               |
+| IAB     | Integrated Access and Backhaul |
+| IE      | Information Element            |
+| MT      | Mobile Termination             |
+| RLC     | Radio Link Control             |
+| RRC     | Radio Resource Control         |
+
+# 1. Scenario
+
+This document aims to gather all the needed requirements to implement the Backhaul Adaptation Protocol (BAP) (Based on TS 38.340-i00 (release 18)).
+
+# 2. General
+
+## 2.1. Entities
+
+BAP is a layer 2 routing protocol that sits on top of the RLC layer and is responsible for routing packages through multiple node hops.
+
+<p>
+  <img src="./images/BAP_layer_structure.png" width=600></br>
+  <em>Figure 2.1-1 - BAP layer structure view (TS 38.340)</em>
+</p>
+
+BAP works with entities:
+
+-   BAP entity at node MT;
+-   BAP entity at node DU;
+-   BAP entity at donor DU.
+
+The transmitting part of BAP entity has a corresponding receiving part of another BAP entity.
+
+<p>
+  <img src="./images/BAP_layer_functional_example.png" width=600></br>
+  <em>Figure 2.1-2 - Example of BAP Layer Functionality (TS 38.340)</em>
+</p>
+
+## 2.2. Services
+
+### 2.2.1 BAP -> upper layers
+
+(Service that needs to be performed by BAP)
+
+-   Data transfer.
+
+### 2.2.2 Lower layer (Per RLC entity) -> BAP
+
+(Services expected from lower levels to BAP)
+
+-   Acknowledged data transfer service;
+-   Unacknowledged data transfer service.
+
+## 2.3. Functions
+
+A BAP sublayer must support the following functions:
+
+-   Data transfer;
+-   Determination of BAP destination and path for packets from upper layers;
+-   Determination of egress BH RLC channels for packets routed to next hop;
+-   Routing of packets to next hop;
+-   BAP header rewriting;
+-   Differentiating traffic to be delivered to upper layers from traffic to be delivered to egress link;
+-   Flow control feedback and polling signalling;
+-   Handling of BH RLF related indications.
+
+## 2.4. Configurations
+
+The configuration of the BAP entity includes:
+
+-   The IAB-node's BAP address(es) via RRC;
+-   The IAB-donor-DU's BAP address via F1AP;
+-   Mapping from next hop BAP address to downstream egress link via F1AP;
+-   Mapping from next hop BAP address to upstream egress link via RRC;
+-   Mapping from upper layer traffic to BAP routing ID in BAP header via F1AP and RRC;
+-   The BAP routing entries via F1AP;
+-   Mapping to egress BH RLC channels via F1AP and RRC;
+-   Flow control feedback type(s) to be provided, if any, via RRC;
+-   Inter-donor-DU re-routing enabling/disabling via F1AP.
+
+Configure **RLC** channels:
+
+-   Via RRC on the IAB-MT;
+-   via F1AP on the IAB-DU/IAB-donor-DU.
+
+The **F1AP** configurations (Which derive from the original F1AP signaling) are:
+
+-   Uplink Traffic to Routing ID Mapping Configuration;
+-   Downlink Traffic to Routing ID Mapping Configuration;
+-   BH Routing Configuration;
+-   BH RLC Channel Mapping Configuration;
+-   Uplink Traffic to BH RLC Channel Mapping Configuration;
+-   Downlink Traffic to BH RLC Channel Mapping Configuration;
+-   Header Rewriting Configuration.
+
+# 3. Procedures
+
+## 3.1. BAP entity handling
+
+### 3.1.1 Entity establishment
+
+When upper layers request establishment of a BAP entity, the node shall:
+
+-   Establish a BAP entity;
+-   Follow the other procedures in this section.
+
+### 3.1.2 Entity release
+
+When upper layers request release of a BAP entity, the node shall:
+
+-   Release the BAP entity and the related BAP configurations.
+
+## 3.2 Data transfer
+
+### 3.2.1 Transmitting Operations
+
+#### **3.2.1.1 General**
+
+Upon **receiving a BAP SDU** from upper layers, the **transmitting part** of the BAP entity shall:
+
+-   **(Clause ####)** Select a BAP address and a BAP path identity for this BAP SDU;
+-   **(Clause ####)** Construct a BAP Data PDU by adding a BAP header to the BAP SDU, where:
+    -   **DESTINATION** field is set to the selected BAP address;
+    -   **PATH** field is set to the selected BAP path identity.
+
+When the BAP entity has a **BAP Data PDU to transmit**, the **transmitting part** of the BAP entity shall:
+
+-   **(Clause ####)** For the boundary IAB-node, if the BAP Data PDU is received from the collocated BAP entity (in the same node), perform the BAP header rewriting operation (if configured);
+-   **(Clause ####)** Perform routing to determine the egress link;
+-   **(Clause ####)** Determine the egress BH RLC channel;
+-   Submit this BAP Data PDU to the selected egress BH RLC channel of the selected egress link.
+
+#### **3.2.1.2 BAP routing ID selection**
+
+**At IAB-node**
+
+At an IAB-node, for a BAP SDU received from upper layers and to be transmitted in upstream direction, the BAP entity performs mapping to a BAP address and BAP path identity based on:
+
+-   Uplink Traffic to Routing ID Mapping Configuration, which is derived from F1AP on the IAB-node in TS 38.473;
+
+-   <span style="color:#33C8FF">_defaultUL-BAP-RoutingID_</span>, which is configured by RRC on the IAB-node in TS 38.331.
+
+Each entry of the Uplink Traffic to Routing ID Mapping Configuration contains:
+
+-   A traffic type specifier, which is indicated by <span style="color:#33C8FF">_UL UP TNL Information_</span> IE for F1-U packets and <span style="color:#33C8FF">_Non-UP TrafficType_</span> IE for non-F1-U packets in TS 38.473;
+
+-   A BAP routing ID, which includes a BAP address and a BAP path identity, indicated by <span style="color:#33C8FF">_BAP Routing ID_</span> IE in <span style="color:#33C8FF">_BH Information_</span> IE in TS 38.473;
+
+For a BAP SDU received from upper layers and to be transmitted in upstream direction, the BAP entity shall:
+
+<pre>
+<b>if</b> the Uplink Traffic to Routing ID Mapping Configuration has not 
+been (re)configured by the F1AP associated with the (logical) DU, where
+this BAP SDU is received, after the last (re)configuration of 
+<span style="color:#33C8FF"><i>defaultUL-BAPRoutingID</i></span> by RRC:
+    <b>select</b> the BAP address and the BAP path identity as configured by
+    <span style="color:#33C8FF"><i>defaultUL-BAP-RoutingID</i></span> in TS 38.331 for non-F1-U packets;
+<b>else</b>:
+    <b>for the</b> BAP SDU encapsulating an F1-U packet:
+        <b>select</b> an entry from the Uplink Traffic to Routing ID Mapping
+        Configuration with its traffic type specifier corresponds to the 
+        destination IP address and TEID of this BAP SDU;
+    <b>for the</b> BAP SDU encapsulating a non-F1-U packet:
+        <b>select</b> an entry from the Uplink Traffic to Routing ID Mapping
+        Configuration with its traffic type specifier corresponds to the 
+        traffic type of this BAP SDU;
+<b>select</b> the BAP address and the BAP path identity from the BAP routing ID in the entry 
+selected above;
+<b>if</b> the selected entry is configured with <span style="color:#33C8FF"><i>Non-F1-terminating IAB-donor Topology
+Indicator</i></span> IE:
+    <b>consider</b> this BAP Data PDU as data to be routed to non-F1-terminating
+    donor topology
+</pre>
+
+**At IAB-donor-DU**
+
+For a BAP SDU received from upper layer at the IAB-donor-DU, the BAP entity performs mapping to a BAP address and a BAP Path identity based on:
+
+-   Downlink Traffic to Routing ID Mapping Configuration, which is derived from <span style="color:#33C8FF"><i>IP-to-layer-2 traffic mapping Information List</i></span> IE configured on the IAB-donor-DU in TS 38.473.
+
+Each entry of the Downlink Traffic to Routing ID Mapping Configuration contains:
+
+-   A destination IP address, which is indicated by <span style="color:#33C8FF"><i>Destination IAB TNL Address</i></span> IE in IP header information IE, including an IPv4 address or IPv6 address or an IPv6 address prefix;
+
+-   An IPv6 flow label, if configured, which is indicated by <span style="color:#33C8FF"><i>IPv6 Flow Label</i></span> IE in <span style="color:#33C8FF"><i>IP header information</i></span> IE;
+
+-   A DSCP, if configured, which is indicated by <span style="color:#33C8FF"><i>DSCP</i></span> IE in <span style="color:#33C8FF"><i>DS Information List</i></span> IE in <span style="color:#33C8FF"><i>IP header information</i></span> IE;
+
+-   A BAP routing ID, which is indicated by <span style="color:#33C8FF"><i>BAP Routing ID</i></span> IE in <span style="color:#33C8FF"><i>BH Information</i></span> IE in TS 38.473.
+
+For a BAP SDU received from upper layers and to be transmitted in downstream direction, the BAP entity shall:
+
+<pre>
+<b>for the</b> BAP SDU encapsulating an IPv6 packet:
+    <span style="color:lightgreen"># (not very relevant) Check TS 38.340</span>
+<b>for the</b> BAP SDU encapsulating an IPv4 packet:
+    <b>Select</b> an entry from the Downlink Traffic to Routing ID Mapping
+    Configuration which fulfils the following conditions:
+        This BAP SDU Destination IP address <span style="color:orange">==</span> Destination IP address in 
+        this entry
+        <span style="color:#BB8FCE">AND</span>
+        This BAP SDU DSCP <span style="color:orange">==</span> DSCP in this entry (if configured)
+<b>select</b> the BAP address and the BAP path identity from the BAP routing ID in
+the entry selected above
+</pre>
+
+#### **3.2.1.3 Routing**
+
+BAP entity performs routing based on the BH Routing Configuration derived from an F1AP message, as specified in TS 38.473.
+Each entry of the BH Routing Configuration contains:
+
+-   <b>BAP Routing ID</b> consisting of a BAP address and a BAP path identity, which is indicated by <span style="color:#33C8FF">_BAP Routing ID_</span> IE;
+
+-   <b>Next Hop BAP Address</b> which is indicated by <span style="color:#33C8FF">_Next-Hop BAP Address_</span> IE;
+
+-   <b>Topology indicator</b>, indicating whether the entry belongs to the non-F1-terminating donor topology, which is optionally indicated by <span style="color:#33C8FF">_Non-F1-terminating IAB-donor Topology Indicator_</span> IE.
+
+For a BAP Data PDU to be transmitted, BAP entity shall:
+
+<pre>
+<b>if</b> the BAP Data PDU corresponds to a BAP SDU received from the upper layer
+<span style="color:#BB8FCE">AND</span>
+<b>if</b> the BH Routing Configuration has not been (re)configured by the F1AP
+associated with the (logical) DU, where this BAP SDU is received, after the 
+last (re)configuration of <span style="color:#33C8FF"><i>defaultUL-BH-RLC-Channel</i></span> by RRC:
+    <b>select</b> the egress link on which the egress BH RLC channel corresponding
+    to <span style="color:#33C8FF"><i>defaultUL-BH-RLC-Channel</i></span> is configured as specified in TS 38.331 for
+    non-F1-U packets;
+<b>else if</b> there is an entry in the BH Routing Configuration whose BAP
+address matches the DESTINATION field, whose BAP path identity is the 
+same as the PATH field, and whose egress link corresponding to the Next Hop
+BAP Address is available:
+    <b>select</b> the egress link corresponding to the Next Hop BAP Address 
+    of the entry;
+<b>else if</b> there is at least one entry in the BH Routing Configuration whose 
+BAP address matches the DESTINATION field, and whose egress link corresponding 
+to the Next Hop BAP Address is available:
+    <b>select</b> an entry from the BH Routing Configuration whose BAP address
+    is the same as the DESTINATION field, and whose egress link corresponding
+    to the Next Hop BAP Address is available;
+    <b>select</b> the egress link corresponding to the Next Hop BAP Address of
+    the entry selected above;
+<b>else if</b>, for the transmitting part of IAB-MT, at least one egress link is
+available, and if <span style="color:#33C8FF"><i>Re-routing Enable Indicator</i></span> IE is set to true by F1AP:
+    <b>if</b> this egress link belongs to F1-terminating donor topology of the
+    boundary IAB-node or the transmitting part of IAB-MT is not at the 
+    boundary IAB-node, and there is an entry in the BH Routing Configuration 
+    not configured with <span style="color:#33C8FF"><i>Non-F1-terminating IAB-donor Topology Indicator</i></span> IE 
+    whose Next Hop BAP Address corresponds to this egress link
+    <span style="color:#BB8FCE">OR</span>
+    <b>if</b> this egress link belongs to non-F1-terminating donor topology, and
+    there is an entry in the BH Routing Configuration configured with
+    <span style="color:#33C8FF"><i>Non-F1-terminating IAB-donor Topology Indicator</i></span> IE whose Next Hop BAP
+    Address corresponds to this egress link:
+        <b>select</b> the egress link;
+        <b>rewrite</b> the BAP header of this BAP Data PDU, where the DESTINATION
+        field is set to the leftmost 10 bits of BAP Routing ID of the entry in
+        the BH Routing Configuration (i.e. BAP address), and the PATH field is 
+        set to the rightmost 10 bits of BAP Routing ID of the entry (i.e. BAP
+        path identity)
+</pre>
+
+#### **3.2.1.4 Mapping to BH RLC Channel**
+
+**Mapping to BH RLC Channel for BAP Data Packets from collocated BAP entity at IAB-node**
+
+Check page 14 and 15
+
+**Mapping to BH RLC Channel for BAP SDUs from upper layers at IAB-node**
+
+Check page 15 and 16
+
+**Mapping to BH RLC Channel at IAB-donor-DU**
+
+Check page 16 and 17
+
+#### **3.2.1.4 BAP header rewriting operation**
+
+Check page 17
+
+### 3.2.2 Receiving Operations
+
+Upon receiving a BAP Data PDU from lower layer (i.e. ingress BH RLC channel), the receiving part of the BAP entity shall:
+
+<pre>
+<b>if</b> DESTINATION field of this BAP Data PDU matches the BAP address, which 
+is configured for this IAB-node by the IAB-donor providing this ingress BH RLC
+channel configuration:
+  <b>remove</b> the BAP header of this BAP Data PDU and deliver the BAP SDU to 
+  upper layers;
+<b>else</b>:
+  <b>deliver</b> the BAP Data Packet to the transmitting part of the collocated 
+  BAP entity.
+</pre>
+
+## 3.3 Flow control
+
+Check page 18
+
+## 3.4 BH RLF related indications
+
+Check page 19
+
+## 3.5 Handling of unknown, unforeseen, and erroneous protocol data
+
+When a BAP Data PDU contains a BAP address which is not included in the applied entries of BH Routing
+Configuration during Routing operation in accordance with clause 5.2.1.3 and the BAP Data PDU contains a BAP
+address which is not the BAP address of this node in accordance with clause 5.2.2 upon receiving; or
+when a BAP Control PDU that contains reserved or invalid values is received the BAP entity shall:
+
+-   discard the received BAP PDU.
+
+# 4 Protocol data units, formats, and parameters
+
+## 4.1 Protocol data units
+
+### 4.1.1 Data PDU
+
+Used to convey:
+
+-   Upper layer data.
+
+### 4.1.2 Control PDU
+
+Used to convey:
+
+-   Flow control feedbacck per BH RLC channel;
+-   Flow control feedback per BAP routing ID;
+-   flow control polling;
+-   BH RLF related indication.
+
+## 4.2 Formats and Parameters
+
+Check pages 20 to 23

doc/IAB_docs/IAB_Info.md

@@ -0,0 +1,123 @@
+<table style="border-collapse: collapse; border: none;">
+  <tr style="border-collapse: collapse; border: none;">
+    <td style="border-collapse: collapse; border: none;">
+      <a href="http://www.openairinterface.org/">
+         <img src="../images/oai_final_logo.png" alt="" border=3 height=50 width=150>
+         </img>
+      </a>
+    </td>
+    <td style="border-collapse: collapse; border: none; vertical-align: center;">
+      <b><font size = "5">OAI IAB Documentation</font></b>
+    </td>
+  </tr>
+</table>
+
+**Table of Contents**
+
+[[_TOC_]]
+
+# Glossary
+
+| Acronym | Description                    |
+| ------- | ------------------------------ |
+| BAP     | Backhaul Adaptation Protocol   |
+| BH      | Backhaul                       |
+| CP      | Control Plane                  |
+| IAB     | Integrated Access and Backhaul |
+| RLC     | Radio Link Control             |
+| RLF     | Radio Link Failure             |
+| RRC     | Radio Resource Control         |
+| TNL     | Transport Network Layer        |
+| UP      | User Plane                     |
+
+# 1. Scenario
+
+This document aims to gather all the needed requirements to implement a 5G SA 3GPP compliant Integrated Access and Backhaul (IAB).
+
+# 2. Protocol Stacks
+
+## 2.1 Protocol stack for the support of F1-U protocol
+
+<img src="./images/Protocol_stack_F1-U.png" width=600>
+
+## 2.2 Protocol stack for the support of F1-C protocol
+
+<img src="./images/Protocol_stack_F1-C.png" width=600>
+
+## 2.3 Protocol stack for the support of IAB-MT's RRC and NAS connections
+
+<img src="./images/Protocol_stack_RRC_NAS.png" width=600>
+
+# 3. Backhaul Adaptation Protocol (BAP) (TS 38.340)
+
+Some info in [BAP_info](./BAP_Info.md)
+
+# 4. F1 Mods (TS 38.470 and 38.473)
+
+Needed functions:
+
+-   BAP mapping configuration function;
+-   gNB-DU resource configuration function;
+-   IAB TNL address configuration function;
+-   IAB UP configuration update function;
+-   Mobile IAB F1 Setup Triggering function; (Can we skip mobile IAB for now?)
+-   Mobile IAB F1 Setup Outcome Notification function. (Can we skip mobile IAB for now?)
+
+# 5. RRC Mods (TS 38.331)
+
+Some info in [RRC_IAB_info](./RRC_IAB_Info.md)
+
+# 6. IAB-MT mandatory features (TS 38.306)
+
+-   Routing using BAP (TS 38.340-i00 (release 18), pages 11-17)
+-   Bearer mapping using BAP (TS 38.340-i00 (release 18), pages 11-17)
+-   IAB-node IP address signalling over RRC (TS 38.331-i00 (release 18), page 133)
+
+<img src="./images/IAB-MT-Requirements.png" width=600>
+
+# 7. IAB Resource Configuration (TS 38.300)
+
+Check TS 38.300-i00 (release 18), pages 122 and 123.
+
+# 8. Required signalling procedures (TS 38.300 and TS 38.401)
+
+## 8.1 IAB-node Integration (TS 38.401-i00, page 87 and 88)
+
+<img src="./images/IAB_node_integration.png" width=600>
+
+## _8.2 IAB-node Migration (Mobile IAB???)_
+
+## 8.3 Topological Management (TS 38.300-i00, page 34)
+
+### 8.3.1 IAB Inter-donor-DU Re-routing (TS 38.401-i00, pages 105, 106)
+
+When an IAB-donor-DU is configured to support inter-donor-DU re-routing, the IAB-donor-DU may identify a rerouted UL IP packet based on the source IP address field of the UL packet, and forwards UL IP packets, whose source IP addresses are anchored at a peer IAB-donor-DU, to this peer IAB-donor-DU via a tunnel. The IAB-donor-DU and the peer IAB-donor-DU may be controlled by the same IAB-donor-CU or by two different IAB-donor-CUs. The interdonor-DU tunnel may be a GTP-U tunnel. The configuration of the tunnel is up to implementation. At the IAB-donor-DU forwarding the UL IP packets, inter-donor-DU tunnelling may be restricted to only a subset of the IP addresses anchored at the peer IAB-donor-DU. For this purpose, the IAB-donor-CU configures the IAB-donor-DU for forwarding the UL IP packets with a list of TNL addresses and/or prefixes for which tunnelling should be permitted and TNL
+address filtering should be exempted.
+
+### 8.3.2 IAB Inter-CU topological redundancy procedure (TS 38.3401-i00, pages 106, 107 and 108)
+
+<img src="./images/IAB_inter-CU_redundancy.png" width=600>
+
+### 8.3.3 IAB Inter-CU topology adaptation procedure (TS 38.3401-i00, pages 108 to 111)
+
+<img src="./images/IAB_inter-CU_topology_adaptation.png" width=600>
+
+### 8.3.4 IAB inter-CU topology adaptation procedure with descendant IAB-node (TS 38.3401-i00, pages 111 to 113)
+
+<img src="./images/IAB_inter-CU_topology_adaptation_descendant.png" width=600>
+
+### 8.3.5 IAB Inter-CU Backhaul RLF recovery for single connected IAB-node (TS 38.3401-i00, pages 113 to 116)
+
+<img src="./images/IAB_inter-CU_BH_RLF_recovery_for_single_node.png" width=600>
+
+## 8.4 OTA timing synchronization (38.300-i00, page 34)
+
+An IAB-DU is subject to the same downlink timing alignment of a gNB. The IAB-DU may use the received downlink
+signal from a parent as a reference to control its downlink timing using TA in conjunction with an additional Tdelta
+parameter received by the collocated IAB-MT from the parent via MAC-CE.
+
+## 8.5 Inter node discovery (38.300-i00, page 35)
+
+Inter node discovery is supported via SSB-based and/or CSI-RS-based measurements. An IAB-node can be configured
+to transmit and receive off synchronization raster SSB signals to discover neighbouring IAB-nodes. The configuration
+is not expected to create a conflict between IAB-DU SSB transmission and IAB-MT SSB measurement windows.

doc/IAB_docs/RRC_IAB_Info.md

@@ -0,0 +1,242 @@
+<table style="border-collapse: collapse; border: none;">
+  <tr style="border-collapse: collapse; border: none;">
+    <td style="border-collapse: collapse; border: none;">
+      <a href="http://www.openairinterface.org/">
+         <img src="../images/oai_final_logo.png" alt="" border=3 height=50 width=150>
+         </img>
+      </a>
+    </td>
+    <td style="border-collapse: collapse; border: none; vertical-align: center;">
+      <b><font size = "5">RRC - IAB related Documentation</font></b>
+    </td>
+  </tr>
+</table>
+
+**Table of Contents**
+
+[[_TOC_]]
+
+# Glossary
+
+| Acronym | Description                    |
+| ------- | ------------------------------ |
+| BAP     | Backhaul Adaptation Protocol   |
+| BH      | Backhaul                       |
+| DL      | Downlink                       |
+| IAB     | Integrated Access and Backhaul |
+| IE      | Information Element            |
+| MCG     | Master Cell Group              |
+| RLC     | Radio Link Control             |
+| RRC     | Radio Resource Control         |
+| SCG     | Secondary Cell Group           |
+| UL      | Uplink                         |
+
+# 1. Scenario
+
+This document aims to gather all the needed requirements to implement IAB in the Radio Resource Control (RRC) level (TS 38.331).
+
+# 2. BAP configuration
+
+The IAB-MT shall:
+
+<pre>
+<b>if</b> the <span style="color:#33C8FF"><i>bap_Config</i></span> is set to <span style="color:#33C8FF"><i>setup</i></span>:
+    <b>if</b> no BAP entity is established:
+        <b>establish</b> a BAP entity as specified in TS 38.340;
+    <b>if</b> <span style="color:#33C8FF"><i>bap-Address</i></span> is included:
+        <b>configure</b> the BAP entity to use the bap-Address as this
+        node's BAP address;
+    <b>if</b> <span style="color:#33C8FF"><i>defaultUL-BAP-RoutingID</i></span> is included:
+        <b>configure</b> the BAP entity to apply the default UL BAP routing ID
+        according to the configuration;
+    <b>if</b> <span style="color:#33C8FF"><i>defaultUL-BH-RLC-Channel</i></span> is included:
+        <b>configure</b> the BAP entity to apply the default UL BH RLC channel
+        according to the configuration;
+    <b>if</b> <span style="color:#33C8FF"><i>flowControlFeedbackType</i></span> is included:
+        <b>configure</b> the BAP entity to apply the flow control feedback according
+        to the configuration;
+<b>if</b> the <span style="color:#33C8FF"><i>bap-Config</i></span> is set to release:
+    <b>release</b> the concerned <span style="color:#33C8FF"><i>bap-Config</i></span>;
+    <b>if</b> there is no other configured <span style="color:#33C8FF"><i>bap-Config</i></span> for the MCG or for the SCG
+        <b>release</b> the BAP entity as specified in TS 38.340.
+</pre>
+
+# 3. IAB other configuration
+
+## 3.1 IP address release
+
+The IAB-MT shall:
+
+<pre>
+<b>if</b> the release is triggered by reception of the <span style="color:#33C8FF"><i>iab-IP-AddressToReleaseList</i></span>:
+    <b>for each</b> <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span> value included in
+    <span style="color:#33C8FF"><i>iab-IP-AddressToReleaseList</i></span>:
+        <b>release</b> the corresponding <span style="color:#33C8FF"><i>IAB-IP-AddressConfiguration</i></span>.
+</pre>
+
+## 3.2 IP address addition/modification
+
+The IAB-MT shall:
+
+<pre>
+<b>for each</b> <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span> value included in the <span style="color:#33C8FF"><i>iab-IP-AddressToAddModList</i></span>
+that is not part of the current IAB-MT configuration:
+    <b>add</b> the IP address indicated in <span style="color:#33C8FF"><i>iab-IP-Address</i></span>, corresponding to the
+    <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span>.
+    <b>if</b> added IP address is <span style="color:#33C8FF"><i>iPv4-Address</i></span>:
+        <b>if</b> <span style="color:#33C8FF"><i>iab-IP-Usage</i></span> is set to <span style="color:#33C8FF"><i>f1-C</i></span>:
+            <b>store</b> the received IPv4 address for F1-C traffic together with
+            the IAB-donor-DU BAP address corresponding to the 
+            <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span>.
+        <b>else if</b> <span style="color:#33C8FF"><i>iab-IP-Usage</i></span> is set to <span style="color:#33C8FF"><i>f1-U</i></span>:
+            <b>store</b> the received IPv4 address for F1-U traffic together with
+            the IAB-donor-DU BAP address corresponding to the 
+            <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span>.
+        <b>else if</b> <span style="color:#33C8FF"><i>iab-IP-Usage</i></span> is set to <span style="color:#33C8FF"><i>non-F1</i></span>:
+            <b>store</b> the received IPv4 address for non-F1 traffic together with
+            the IAB-donor-DU BAP address corresponding to the 
+            <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span>.
+        <b>else</b>:
+            <b>store</b> the received IPv4 address for all traffic together with 
+            the IAB-donor-DU BAP address corresponding to the 
+            <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span>.
+    <b>else if</b> <span style="color:#33C8FF"><i>iPv6-Address</i></span> is included:
+        <b>if</b> <span style="color:#33C8FF"><i>iab-IP-Usage</i></span> is set to <span style="color:#33C8FF"><i>f1-C</i></span>:
+            <b>store</b> the received IPv6 address for F1-C traffic together with
+            the IAB-donor-DU BAP address corresponding to the
+            <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span>.
+        <b>else if</b> <span style="color:#33C8FF"><i>iab-IP-Usage</i></span> is set to <span style="color:#33C8FF"><i>f1-U</i></span>:
+            <b>store</b> the received IPv6 address for F1-U traffic together with
+            the IAB-donor-DU BAP address corresponding to the 
+            <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span>.
+        <b>else if</b> <span style="color:#33C8FF"><i>iab-IP-Usage</i></span> is set to <span style="color:#33C8FF"><i>non-F1</i></span>:
+            <b>store</b> the received IPv6 address for non-F1 traffic together with
+            the IAB-donor-DU BAP address corresponding to the 
+            <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span>.
+        <b>else</b>:
+            <b>store</b> the received IPv6 address for all traffic together with the
+            IAB-donor-DU BAP address corresponding to the 
+            <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span>.
+    <b>else if</b> <span style="color:#33C8FF"><i>iPv6-Prefix</i></span> is included in <span style="color:#33C8FF"><i>iab-IP-AddressToAddModList</i></span>:
+        <b>if</b> <span style="color:#33C8FF"><i>iab-IP-Usage</i></span> is set to <span style="color:#33C8FF"><i>f1-C</i></span>:
+            <b>store</b> the received IPv6 address prefix for F1-C traffic together
+            with the IAB-donor-DU BAP address corresponding to the
+            <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span>.
+        <b>else if</b> <span style="color:#33C8FF"><i>iab-IP-Usage</i></span> is set to <span style="color:#33C8FF"><i>f1-U</i></span>:
+            <b>store</b> the received IPv6 address prefix for F1-U traffic together
+            with the IAB-donor-DU BAP address corresponding to the
+            <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span>.
+        <b>else if</b> <span style="color:#33C8FF"><i>iab-IP-Usage</i></span> is set to <span style="color:#33C8FF"><i>non-F1</i></span>:
+            <b>store</b> the received IPv6 address prefix for non-F1 traffic
+            together with the IAB-donor-DU BAP address corresponding to the
+            <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span>.
+        <b>else</b>:
+            <b>store</b> the received IPv6 address prefix for all traffic together
+            with the IAB-donor-DU BAP address corresponding to the
+            <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span>.
+<b>for each</b> <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span> value included in the <span style="color:#33C8FF"><i>iab-IP-AddressToAddModList</i></span>
+that is part of the current IA-BMT configuration:
+    <b>modify</b> the IP address configuration(s) in accordance with the
+    <span style="color:#33C8FF"><i>IAB-IP-AddressConfiguration</i></span> corresponding to the <span style="color:#33C8FF"><i>iab-IP-AddressIndex</i></span>.
+</pre>
+
+# 4 "IAB Other Information" (Procedure)
+
+<p>
+  <img src="./images/IAB_other_info.png" width=600></br>
+  <em>Figure 4.1 - IAB Other information procedure (TS 38.331)</em>
+</p>
+The IAB Other Information procedure is used by IAB-MT to request the IAB-donor-CU to allocate IP address or
+inform the IAB-donor-CU of the IP address for the collocated IAB-DU.
+
+## 4.1 Initiation
+
+Upon initiation of the procedure, the IAB-MT shall:
+
+-   initiate transmission of the <span style="color:#33C8FF"><i>IABOtherInformation</i></span> message.
+
+## 4.2 Actions related to transmission of IABOtherInformation message
+
+The IAB-MT shall set the contents of <span style="color:#33C8FF"><i>IABOtherInformation</i></span> message as follows:
+
+<pre>
+<b>if</b> the procedure is used to request IP addresses:
+    <b>if</b> IPv4 addresses are requested:
+        <b>set</b> the <span style="color:#33C8FF"><i>iab-IPv4-AddressNumReq</i></span> to the number of IPv4 addresses
+        requested per specific usage;
+    <b>if</b> IPv6 addresses or IPv6 address prefixes are requested:
+        <b>if</b> IPv6 addresses are requested:
+            <b>set</b> the <span style="color:#33C8FF"><i>iab-IPv6-AddressNumReq</i></span> to the number of IPv6 addresses
+            requested per specific usage;
+        <b>else if</b> IPv6 address prefixes are requested:
+            <b>set</b> the <span style="color:#33C8FF"><i>iab-IPv6-AddressPrefixReq</i></span> to <span style="color:orange"><i>true</i></span> per specific usage;
+<b>if</b> the procedure is used to report IP addresses:
+    <b>if</b> IPv4 addresses are reported:
+        <b>include</b> <span style="color:#33C8FF"><i>iPv4-Address</i></span> in <span style="color:#33C8FF"><i>iab-IPv4-AddressReport</i></span>, and for each IP
+        address included:
+            <b>if</b> IPv4 addresses are used for F1-C traffic:
+                <b>include</b> these addresses in <span style="color:#33C8FF"><i>f1-C-Traffic-IP-Address</i></span>.
+            <b>if</b> IPv4 addresses are used for F1-U traffic:
+                <b>include</b> these addresses in <span style="color:#33C8FF"><i>f1-U-Traffic-IP-Address</i></span>.
+            <b>if</b> IPv4 address are used for non-F1 traffic:
+                <b>include</b> these addresses in <span style="color:#33C8FF"><i>non-f1-Traffic-IP-Address</i></span>.
+            <b>if</b> IPv4 addresses are used for all traffic:
+                <b>include</b> these addresses in <span style="color:#33C8FF"><i>all-Traffic-IAB-IP-Address</i></span>.
+    <b>if</b> IPv6 addresses or IPv6 address prefixes are reported:
+        <b>if</b> IPv6 addresses are reported:
+            <b>include</b> <span style="color:#33C8FF"><i>iPv6-Address</i></span> in <span style="color:#33C8FF"><i>iab-IPv6-AddressReport</i></span>.
+            <b>for each</b> IP address included (in previous step):
+                <b>if</b> IPv6 addresses are used for F1-C traffic:
+                    <b>include</b> these addresses in <span style="color:#33C8FF"><i>f1-C-Traffic-IP-Address</i></span>.
+                <b>if</b> IPv6 addresses are used for F1-U traffic:
+                    <b>include</b> these addresses in <span style="color:#33C8FF"><i>f1-U-Traffic-IP-Address</i></span>.
+                <b>if</b> IPv6 addresses are used for non-F1 traffic:
+                    <b>include</b> these addresses in <span style="color:#33C8FF"><i>non-f1-Traffic-IP-Address</i></span>.
+                <b>if</b> IPv6 addresses are used for all traffic:
+                    <b>include</b> these addresses in <span style="color:#33C8FF"><i>all-Traffic-IAB-IP-Address</i></span>.
+        <b>else if</b> IPv6 address prefixes are reported:
+            <b>include</b> these <span style="color:#33C8FF"><i>iPv6-Prefix</i></span> in <span style="color:#33C8FF"><i>iab-IPv6-PrefixReport</i></span>.
+            <b>for each</b> IP address prefix included (in previous step):
+                <b>if</b> this IPv6 address prefix is used for F1-C traffic:
+                    <b>include</b> this prefix in <span style="color:#33C8FF"><i>f1-C-Traffic-IP-Address</i></span>.
+                <b>if</b> this IPv6 address prefix is used for F1-U traffic:
+                    <b>include</b> this prefix in <span style="color:#33C8FF"><i>f1-U-Traffic-IP-Address</i></span>.
+                <b>if</b> this IPv6 address prefix is used for non-F1 traffic:
+                    <b>include</b> this prefix in <span style="color:#33C8FF"><i>non-f1-Traffic-IP-Address</i></span>.
+                <b>if</b> this IPv6 address prefix is used for all traffic:
+                    <b>include</b> this prefix in <span style="color:#33C8FF"><i>all-Traffic-IAB-IP-Address</i></span>.
+<b>if</b> the IAB-MT is in (NG)EN-DC
+<span style="color:#BB8FCE">OR</span>
+<b>if</b> the IAB-MT is in NR-DC and the IAB Other Information procedure is 
+towards the IAB-donor-CU in the SN:
+    <b>if</b> SRB3 is configured:
+        <b>submit</b> the <span style="color:#33C8FF"><i>IABOtherInformation</i></span> message via SRB3 to lower layers 
+        for transmission;
+    <b>else if</b> the IAB-MT is in (NG)EN-DC:
+        <b>submit</b> the <span style="color:#33C8FF"><i>IABOtherInformation</i></span> message via the E-UTRA MCG embedded 
+        in E-UTRA RRC message <span style="color:#33C8FF"><i>ULInformationTransferMRDC</i></span> as specified in 
+        TS 36.331;
+    <b>else</b>:
+        <b>submit</b> the <span style="color:#33C8FF"><i>IABOtherInformation</i></span> message via the NR MCG embedded 
+        in NR RRC message <span style="color:#33C8FF"><i>ULInformationTransferMRDC</i></span>;
+<b>else</b>:
+    <b>submit</b> the <span style="color:#33C8FF"><i>IABOtherInformation</i></span> message to lower layers for transmission.
+</pre>
+
+## 4.3 Message Definition _IABOtherInformation_
+
+Consult pages 454 to 457 of TS 38.331-i00 (release 18 2023-12)
+
+# 5 Information Elements (IE)
+
+## 5.1 _IAB-IP-Adress_
+
+Consult page 1292 of TS 38.331-i00 (release 18 2023-12)
+
+## 5.2 _IAB-IP-AddressIndex_
+
+Consult pages 1292 and 1293 of TS 38.331-i00 (release 18 2023-12)
+
+## 5.3 _IAB-IP-Usage_
+
+Consult page 1293 of TS 38.331-i00 (release 18 2023-12)

executables/nr-softmodem.c

@@ -60,6 +60,8 @@ unsigned short config_frames[4] = {2,9,11,13};
 #include "common/utils/LOG/vcd_signal_dumper.h"
 #include "UTIL/OPT/opt.h"
 #include "LAYER2/nr_pdcp/nr_pdcp_oai_api.h"
+#include "LAYER2/BAP/bap_oai_api.h"
+#include "LAYER2/BAP/iab_info_management.h"
 
 #include "intertask_interface.h"
 
@@ -81,6 +83,8 @@ unsigned short config_frames[4] = {2,9,11,13};
 #include "gnb_config.h"
 #include "openair2/E1AP/e1ap_common.h"
 
+#include "openair2/LAYER2/NR_MAC_gNB/nr_mac_gNB.h" // need to get info from MAC
+
 #ifdef E2_AGENT
 #include "openair2/E2AP/flexric/src/agent/e2_agent_api.h"
 #include "openair2/E2AP/RAN_FUNCTION/init_ran_func.h"
@@ -308,6 +312,9 @@ static int create_gNB_tasks(ngran_node_t node_type, configmodule_interface_t *cf
     RC.nrrrc = calloc(1, sizeof(*RC.nrrrc));
     RC.nrrrc[0] = calloc(1,sizeof(gNB_RRC_INST));
     RCconfig_NRRRC(RC.nrrrc[0]);
+    // IAB
+    RC.iab = calloc(1, sizeof(*RC.iab));
+    RC.iab[0] = calloc(1, sizeof(gNB_IAB_INFO));
   }
 
   if (RC.nb_nr_inst > 0 &&
@@ -317,7 +324,7 @@ static int create_gNB_tasks(ngran_node_t node_type, configmodule_interface_t *cf
     init_pdcp();
   }
 
-  if (is_x2ap_enabled() ) { //&& !NODE_IS_DU(node_type)
+  if (is_x2ap_enabled() ) { //&& !NODE_IS_DU(node_type), or DU_IAB
 	  LOG_I(X2AP, "X2AP enabled \n");
 	  __attribute__((unused)) uint32_t x2_register_gnb_pending = gNB_app_register_x2 (gnb_id_start, gnb_id_end);
   }
@@ -560,7 +567,6 @@ void init_pdcp(void) {
 }
 
 #ifdef E2_AGENT
-#include "openair2/LAYER2/NR_MAC_gNB/nr_mac_gNB.h" // need to get info from MAC
 static void initialize_agent(ngran_node_t node_type, e2_agent_args_t oai_args)
 {
   AssertFatal(oai_args.sm_dir != NULL , "Please, specify the directory where the SMs are located in the config file, i.e., add in config file the next line: e2_agent = {near_ric_ip_addr = \"127.0.0.1\"; sm_dir = \"/usr/local/lib/flexric/\");} ");
@@ -673,7 +679,7 @@ int main( int argc, char **argv ) {
 
   if (RC.nb_nr_L1_inst > 0)
     RCconfig_NR_L1();
-
+  
   if (NFAPI_MODE != NFAPI_MODE_PNF) {
     int ret = create_gNB_tasks(node_type, uniqCfg);
     AssertFatal(ret == 0, "cannot create ITTI tasks\n");
@@ -744,8 +750,9 @@ int main( int argc, char **argv ) {
   }
 
   // wait for F1 Setup Response before starting L1 for real
-  if (NODE_IS_DU(node_type) || NODE_IS_MONOLITHIC(node_type))
+  if (NODE_IS_DU(node_type) || NODE_IS_MONOLITHIC(node_type)){
     wait_f1_setup_response();
+  }
 
   if (RC.nb_RU > 0)
     start_NR_RU();

executables/nr-ue.c

@@ -816,16 +816,16 @@ void *UE_thread(void *arg)
         delNotifiedFIFO_elt(res);
         start_rx_stream=0;
       } else {
-	if (IS_SOFTMODEM_IQPLAYER || IS_SOFTMODEM_IQRECORDER) {
-	  // For IQ recorder/player we force synchronization to happen in 280 ms
-	  while (trashed_frames != 28) {
-	    readFrame(UE, &timestamp, true);
-	    trashed_frames+=2;
-	  }
-	} else {
-	  readFrame(UE, &timestamp, true);
-	  trashed_frames+=2;
-	}
+        if (IS_SOFTMODEM_IQPLAYER || IS_SOFTMODEM_IQRECORDER) {
+          // For IQ recorder/player we force synchronization to happen in 280 ms
+          while (trashed_frames != 28) {
+            readFrame(UE, &timestamp, true);
+            trashed_frames+=2;
+          }
+        } else {
+          readFrame(UE, &timestamp, true);
+          trashed_frames+=2;
+        }
         continue;
       }
     }

openair2/COMMON/f1ap_messages_types.h

@@ -162,6 +162,10 @@ typedef struct f1ap_setup_req_s {
     f1ap_served_cell_info_t info;
     f1ap_gnb_du_system_info_t *sys_info;
   } cell[F1AP_MAX_NB_CELLS];
+
+  // BIT STRING (SIZE(10))
+  uint16_t bap_address;
+
 } f1ap_setup_req_t;
 
 typedef struct f1ap_du_register_req_t {
@@ -195,6 +199,8 @@ typedef struct f1ap_setup_resp_s {
   /// rrc version
   uint8_t rrc_ver[3];
 
+  uint16_t bap_address;
+
 } f1ap_setup_resp_t;
 
 typedef struct f1ap_gnb_cu_configuration_update_s {
@@ -283,10 +289,34 @@ typedef struct f1ap_ul_rrc_message_s {
   int      rrc_container_length;
 } f1ap_ul_rrc_message_t;
 
+/* [IAB] related structs */
+typedef struct f1ap_bAPRoutingID_s{
+  uint16_t bAPAddress;
+  uint16_t bAPPathID;
+}f1ap_bAPRoutingID_t;
+
+typedef struct f1ap_EgressBHRLCCHItem_s{
+  uint16_t nextHopBAPAddress;
+  uint16_t bHRLCChannelID;
+}f1ap_EgressBHRLCCHItem_t;
+
+typedef struct f1ap_bHInfo_s{
+  f1ap_bAPRoutingID_t bAProutingID;
+  bool is_bAProutingID_set;
+  f1ap_EgressBHRLCCHItem_t *egressBHRLCCHList;
+  int egressList_length;
+}f1ap_bHInfo_t;
+
+/* [IAB] end*/
+
 typedef struct f1ap_up_tnl_s {
   in_addr_t tl_address; // currently only IPv4 supported
   teid_t  teid;
   uint16_t port;
+  // [IAB] info
+  f1ap_bHInfo_t bh_info;
+  bool is_bh_info_set;
+  // ----------
 } f1ap_up_tnl_t;
 
 typedef enum preemption_capability_e {
@@ -356,6 +386,69 @@ typedef struct f1ap_srb_to_be_setup_s {
   uint8_t        lcid;
 } f1ap_srb_to_be_setup_t;
 
+/* [IAB] related structures -- */
+typedef struct f1ap_iPHeaderInformation_s{
+  union DestinationIABTNLAddress{
+    in_addr_t iPv4Address;
+    // ipv6Address;
+    // ipv6Prefix;
+  } destinationIABTNLAddress;
+  enum {
+    ipv4Address,
+    ipv6Address,
+    ipv6Prefix
+  } destinationIABTNLAddress_type;
+  uint8_t *dsInformationList;
+  int infoList_length;
+  uint32_t iPv6FlowLabel;
+}f1ap_iPHeaderInformation_t;
+
+typedef struct f1ap_iPtolayer2TrafficMappingInfo_Item_s{
+  uint32_t mappingInformationIndex;
+  f1ap_iPHeaderInformation_t iPHeaderInformation;
+  f1ap_bHInfo_t bHInfo;
+}f1ap_iPtolayer2TrafficMappingInfo_Item_t;
+
+typedef struct f1ap_bAPlayerBHRLCchannelMappingInfo_Item_s{
+  uint32_t mappingInformationIndex;
+  uint16_t priorHopBAPAddress;
+  uint16_t ingressbHRLCChannelID;
+  uint16_t nextHopBAPAddress;
+  uint16_t egressbHRLCChannelID;
+}f1ap_bAPlayerBHRLCchannelMappingInfo_Item_t;
+
+typedef struct traffic_mapping_info_s{
+  union {
+    struct{
+      f1ap_iPtolayer2TrafficMappingInfo_Item_t *iPtolayer2TrafficMappingInfoToAdd;
+      int add_length;
+      uint32_t *iPtolayer2TrafficMappingInfoToRemove;
+      int remove_length;
+    }iPtolayer2TrafficMappingInfo;
+    struct{
+      f1ap_bAPlayerBHRLCchannelMappingInfo_Item_t *bAPlayerBHRLCchannelMappingInfoToAdd;
+      int add_length;
+      uint32_t *bAPlayerBHRLCchannelMappingInfoToRemove;
+      int remove_length;
+    }bAPlayerBHRLCchannelMappingInfo;
+  };
+  enum  {
+    mapping_info_iPtolayer2TrafficMappingInfo,
+    mapping_info_bAPlayerBHRLCchannelMappingInfo
+  } type;
+}traffic_mapping_info_t;
+
+typedef struct f1ap_bhchannel_to_be_setup_s {
+  uint16_t            bHRLCChannelID;
+  /* TODO: f1ap_qos_flow_level_qos_parameters_t bhch_qos; */
+  rlc_mode_t          rlc_mode;
+  bool                is_bap_Ctrl_PDU_Channel; // should be ENUMERATED {true, ...}
+  traffic_mapping_info_t trafficMappingInfo;
+  bool                is_trafficMappingInfo_set;
+} f1ap_bhchannel_to_be_setup_t;
+
+/* -- [IAB] end of related structures */
+
 typedef struct f1ap_rb_failed_to_be_setup_s {
   long           rb_id;
 } f1ap_rb_failed_to_be_setup_t;
@@ -385,6 +478,7 @@ typedef struct du_to_cu_rrc_information_s {
 typedef enum QoS_information_e {
   NG_RAN_QoS    = 0,
   EUTRAN_QoS    = 1,
+  bHRLCCH_QoS   = 2,
 } QoS_information_t;
 
 typedef enum ReconfigurationCompl_e {
@@ -423,7 +517,43 @@ typedef struct f1ap_ue_context_setup_s {
   ReconfigurationCompl_t ReconfigComplOutcome;
   uint8_t *rrc_container;
   int      rrc_container_length;
-} f1ap_ue_context_setup_t, f1ap_ue_context_modif_req_t, f1ap_ue_context_modif_resp_t;
+} f1ap_ue_context_setup_t;
+
+typedef struct f1ap_ue_context_modif_req_s {
+  uint32_t gNB_CU_ue_id;
+  uint32_t gNB_DU_ue_id;
+  // SpCell Info
+  f1ap_plmn_t plmn;
+  uint64_t nr_cellid;
+  uint8_t servCellIndex;
+  uint8_t *cellULConfigured;
+  uint32_t servCellId;
+  cu_to_du_rrc_information_t *cu_to_du_rrc_information;
+  uint8_t  cu_to_du_rrc_information_length;
+  //uint8_t *du_to_cu_rrc_information;
+  du_to_cu_rrc_information_t *du_to_cu_rrc_information;
+  uint32_t  du_to_cu_rrc_information_length;
+  f1ap_drb_to_be_setup_t *drbs_to_be_setup;
+  uint8_t  drbs_to_be_setup_length;
+  f1ap_drb_to_be_setup_t *drbs_to_be_modified;
+  uint8_t  drbs_to_be_modified_length;
+  QoS_information_t QoS_information_type;
+  uint8_t  drbs_failed_to_be_setup_length;
+  f1ap_rb_failed_to_be_setup_t *drbs_failed_to_be_setup;
+  f1ap_srb_to_be_setup_t *srbs_to_be_setup;
+  uint8_t  srbs_to_be_setup_length;
+  uint8_t  srbs_failed_to_be_setup_length;
+  uint8_t drbs_to_be_released_length;
+  f1ap_drb_to_be_released_t *drbs_to_be_released;
+  f1ap_rb_failed_to_be_setup_t *srbs_failed_to_be_setup;
+  ReconfigurationCompl_t ReconfigComplOutcome;
+  uint8_t *rrc_container;
+  int      rrc_container_length;
+  // [IAB] BH RLC channels
+  f1ap_bhchannel_to_be_setup_t *bhchannels_to_be_setup;
+  uint8_t bhchannels_to_be_setup_length;
+
+} f1ap_ue_context_modif_req_t, f1ap_ue_context_modif_resp_t;
 
 typedef enum F1ap_Cause_e {
   F1AP_CAUSE_NOTHING,  /* No components present */

openair2/F1AP/f1ap_cu_interface_management.c

@@ -109,6 +109,12 @@ int CU_handle_F1_SETUP_REQUEST(instance_t instance, sctp_assoc_t assoc_id, uint3
     memcpy(req->gNB_DU_name, ie->value.choice.GNB_DU_Name.buf, ie->value.choice.GNB_DU_Name.size);
     LOG_D(F1AP, "req->gNB_DU_name %s \n", req->gNB_DU_name);
   }
+  /* BAPAddress*/
+  F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_F1SetupRequestIEs_t, ie, container, F1AP_ProtocolIE_ID_id_BAPAddress, false);
+  if(ie != NULL){
+    BIT_STRING_TO_NR_BAPADDRESS(&ie->value.choice.BAPAddress, req->bap_address);
+    LOG_D(F1AP, "req->bap_address %d \n", req->bap_address);
+  }
   /* GNB_DU_Served_Cells_List */
   F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_F1SetupRequestIEs_t, ie, container,
                              F1AP_ProtocolIE_ID_id_gNB_DU_Served_Cells_List, true);
@@ -346,6 +352,16 @@ int CU_send_F1_SETUP_RESPONSE(sctp_assoc_t assoc_id, f1ap_setup_resp_t *f1ap_set
     os->buf[i] = f1ap_setup_resp->rrc_ver[i];
   ie4->value.choice.RRC_Version.iE_Extensions = (struct F1AP_ProtocolExtensionContainer *)p;
 
+  /* optional [IAB] */
+  /* c6. BAPAddress*/
+  if (f1ap_setup_resp->bap_address != 0) {
+    asn1cSequenceAdd(out->protocolIEs.list, F1AP_F1SetupResponseIEs_t, bap_addr);
+    bap_addr->id                        = F1AP_ProtocolIE_ID_id_BAPAddress;
+    bap_addr->criticality               = F1AP_Criticality_ignore;
+    bap_addr->value.present             = F1AP_F1SetupResponseIEs__value_PR_BAPAddress;
+    NR_BAPADDRESS_TO_BIT_STRING(f1ap_setup_resp->bap_address, &bap_addr->value.choice.BAPAddress);
+  }
+
   /* encode */
   if (f1ap_encode_pdu(&pdu, &buffer, &len) < 0) {
     LOG_E(F1AP, "Failed to encode F1 setup response\n");

openair2/F1AP/f1ap_cu_ue_context_management.c

@@ -41,6 +41,20 @@
 #include <openair3/ocp-gtpu/gtp_itf.h>
 #include "LAYER2/nr_pdcp/nr_pdcp_oai_api.h"
 
+#include "F1AP_BAPlayerBHRLCchannelMappingInfo.h"
+#include "F1AP_BAPlayerBHRLCchannelMappingInfo-Item.h"
+#include "F1AP_IPtolayer2TrafficMappingInfo.h"
+#include "F1AP_IPtolayer2TrafficMappingInfoList.h"
+#include "F1AP_IPtolayer2TrafficMappingInfo-Item.h"
+#include "F1AP_DSCP.h"
+#include "F1AP_DSInformationList.h"
+#include "F1AP_EgressBHRLCCHItem.h"
+#include "F1AP_EgressBHRLCCHList.h"
+#include "F1AP_MappingInformationIndex.h"
+#include "F1AP_MappingInformationtoRemove.h"
+#include "F1AP_BAPlayerBHRLCchannelMappingInfoList.h"
+#include "F1AP_ProtocolExtensionContainer.h"
+
 static void setQos(F1AP_NonDynamic5QIDescriptor_t **toFill)
 {
   asn1cCalloc(*toFill, tmp);
@@ -1444,12 +1458,36 @@ int CU_send_UE_CONTEXT_MODIFICATION_REQUEST(sctp_assoc_t assoc_id, f1ap_ue_conte
         uLUPTNLInformation_ToBeSetup_Item->uLUPTNLInformation.present = F1AP_UPTransportLayerInformation_PR_gTPTunnel;
         asn1cCalloc( uLUPTNLInformation_ToBeSetup_Item->uLUPTNLInformation.choice.gTPTunnel,
                    gTPTunnel);
-        /* 12.3.1.1.1 transportLayerAddress */
+        /* 12.1.3.1.1.1 transportLayerAddress */
         TRANSPORT_LAYER_ADDRESS_IPv4_TO_BIT_STRING(f1ap_ue_context_modification_req->drbs_to_be_setup[i].up_ul_tnl[j].tl_address,
                           &gTPTunnel->transportLayerAddress);
-        /* 12.3.1.1.2 gTP_TEID */
+        /* 12.1.3.1.1.2 gTP_TEID */
         INT32_TO_OCTET_STRING(f1ap_ue_context_modification_req->drbs_to_be_setup[i].up_ul_tnl[j].teid,
                 &gTPTunnel->gTP_TEID);
+        
+        /* 12.1.3.2 BHInfo [IAB] */
+        if(f1ap_ue_context_modification_req->drbs_to_be_setup[i].up_ul_tnl[j].is_bh_info_set){
+          f1ap_bHInfo_t *bh_info =  &f1ap_ue_context_modification_req->drbs_to_be_setup[i].up_ul_tnl[j].bh_info;
+          asn1cSequenceAdd(uLUPTNLInformation_ToBeSetup_Item->iE_Extensions, F1AP_ULUPTNLInformation_ToBeSetup_ItemExtIEs_t,  ulupinfo_ie);
+          ulupinfo_ie->id                     = F1AP_ProtocolIE_ID_id_BHInfo;
+          ulupinfo_ie->criticality            = F1AP_Criticality_ignore;
+          ulupinfo_ie->extensionValue.present = F1AP_ULUPTNLInformation_ToBeSetup_ItemExtIEs__extensionValue_PR_BHInfo;
+
+          F1AP_BHInfo_t *Bhinfo = &ulupinfo_ie->extensionValue.choice.BHInfo;
+          if(bh_info->is_bAProutingID_set){
+            Bhinfo->bAProutingID = calloc(1, sizeof(F1AP_BAPRoutingID_t));
+            NR_BAPADDRESS_TO_BIT_STRING(bh_info->bAProutingID.bAPAddress, &Bhinfo->bAProutingID->bAPAddress);
+            NR_BAPPATHID_TO_BIT_STRING(bh_info->bAProutingID.bAPPathID, &Bhinfo->bAProutingID->bAPPathID);
+          }
+          if(bh_info->egressList_length > 0){
+            Bhinfo->egressBHRLCCHList = calloc(bh_info->egressList_length, sizeof(F1AP_EgressBHRLCCHItem_t));
+            for(int k = 0; k < bh_info->egressList_length; k++){
+              asn1cSequenceAdd(Bhinfo->egressBHRLCCHList->list, F1AP_EgressBHRLCCHItem_t, egressLink);
+              NR_BAPADDRESS_TO_BIT_STRING(bh_info->egressBHRLCCHList[k].nextHopBAPAddress, &egressLink->nextHopBAPAddress);
+              NR_BHRLCCHANNELID_TO_BIT_STRING(bh_info->egressBHRLCCHList[k].bHRLCChannelID, &egressLink->bHRLCChannelID);
+            }
+          }
+        }
       }
       /* 12.1.4 rLCMode */
       /* TODO use rlc_mode from f1ap_drb_to_be_setup */
@@ -1575,6 +1613,198 @@ int CU_send_UE_CONTEXT_MODIFICATION_REQUEST(sctp_assoc_t assoc_id, f1ap_ue_conte
     }
   }
 
+  /* 
+    [IAB]
+    c.31 BH_RLC_ChannelToBeSetup_List 
+    31 (31 is the position it occupies in the message TS)
+  */
+  if (f1ap_ue_context_modification_req->bhchannels_to_be_setup_length > 0){
+    asn1cSequenceAdd(out->protocolIEs.list, F1AP_UEContextModificationRequestIEs_t, ie31);
+    ie31->id                             = F1AP_ProtocolIE_ID_id_BHChannels_ToBeSetupMod_List;
+    ie31->criticality                    = F1AP_Criticality_reject;
+    ie31->value.present                  = F1AP_UEContextModificationRequestIEs__value_PR_BHChannels_ToBeSetupMod_List;
+
+    for (int i = 0; i < f1ap_ue_context_modification_req->bhchannels_to_be_setup_length; i++) {
+      asn1cSequenceAdd(ie31->value.choice.BHChannels_ToBeSetupMod_List.list,
+                     F1AP_BHChannels_ToBeSetupMod_ItemIEs_t, bhchs_toBeSetupMod_item_ies);
+      bhchs_toBeSetupMod_item_ies->id            = F1AP_ProtocolIE_ID_id_BHChannels_ToBeSetupMod_Item;
+      bhchs_toBeSetupMod_item_ies->criticality   = F1AP_Criticality_reject;
+      bhchs_toBeSetupMod_item_ies->value.present = F1AP_BHChannels_ToBeSetupMod_ItemIEs__value_PR_BHChannels_ToBeSetupMod_Item;
+      /* 31.1 BHChannels_ToBeSetupMod_Item */
+      F1AP_BHChannels_ToBeSetupMod_Item_t *bhchs_toBeSetupMod_item=
+          &bhchs_toBeSetupMod_item_ies->value.choice.BHChannels_ToBeSetupMod_Item;
+      
+      /* 31.1.1 bHRLCChannelID */ 
+      NR_BHRLCCHANNELID_TO_BIT_STRING(f1ap_ue_context_modification_req->bhchannels_to_be_setup[i].bHRLCChannelID,
+                                      &bhchs_toBeSetupMod_item->bHRLCChannelID);
+
+      /* 31.1.2 bHQoSInformation CHOICE*/
+      if(f1ap_ue_context_modification_req->QoS_information_type == bHRLCCH_QoS){
+        /* bHRLCCHQoS */
+        /*
+        bhchs_toBeSetupMod_item->bHQoSInformation.present = F1AP_BHQoSInformation_PR_bHRLCCHQoS;
+        bhchs_toBeSetupMod_item->bHQoSInformation.choice.bHRLCCHQoS = (F1AP_QoSFlowLevelQoSParameters_t *)calloc(1, sizeof(F1AP_QoSFlowLevelQoSParameters_t));
+        bhchs_toBeSetupMod_item->bHQoSInformation.choice.bHRLCCHQoS->
+        */
+        
+      }else if (f1ap_ue_context_modification_req->QoS_information_type == EUTRAN_QoS){
+        /* EUTRAN_QoS */
+      }else{
+        /* cPTrafficType */
+        bhchs_toBeSetupMod_item->bHQoSInformation.present = F1AP_BHQoSInformation_PR_cPTrafficType;
+        bhchs_toBeSetupMod_item->bHQoSInformation.choice.cPTrafficType = 1; // integer (hardcoded for now)
+      }
+
+      /* 31.1.3 rLCmode */
+      bhchs_toBeSetupMod_item->rLCmode = f1ap_ue_context_modification_req->bhchannels_to_be_setup[i].rlc_mode;
+    
+
+      /* 31.1.4 bAPCtrlPDUChannel */
+      if(f1ap_ue_context_modification_req->bhchannels_to_be_setup[i].is_bap_Ctrl_PDU_Channel == true){ // 1 being true 
+        bhchs_toBeSetupMod_item->bAPCtrlPDUChannel = calloc(1, sizeof(F1AP_BAPCtrlPDUChannel_t));
+        bhchs_toBeSetupMod_item->bAPCtrlPDUChannel = F1AP_BAPCtrlPDUChannel_true;
+      }
+      
+
+      /* 31.1.5 trafficMappingInfo */
+      if(f1ap_ue_context_modification_req->bhchannels_to_be_setup[i].is_trafficMappingInfo_set){
+        LOG_I(F1AP, "Mapping Info triggered\n");
+        bhchs_toBeSetupMod_item->trafficMappingInfo = calloc(1, sizeof(F1AP_TrafficMappingInfo_t));
+        traffic_mapping_info_t traffic_mapping_info = f1ap_ue_context_modification_req->bhchannels_to_be_setup[i].trafficMappingInfo;
+        // iPtolayer2TrafficMappingInfo
+        if (traffic_mapping_info.type == mapping_info_iPtolayer2TrafficMappingInfo){
+          bhchs_toBeSetupMod_item->trafficMappingInfo->present = F1AP_TrafficMappingInfo_PR_iPtolayer2TrafficMappingInfo;
+          asn1cCalloc(bhchs_toBeSetupMod_item->trafficMappingInfo->choice.iPtolayer2TrafficMappingInfo, iPToL2Info);
+          
+          if(traffic_mapping_info.iPtolayer2TrafficMappingInfo.add_length > 0){
+
+            // Should I use .list here?
+            iPToL2Info->iPtolayer2TrafficMappingInfoToAdd = calloc(1, sizeof(F1AP_IPtolayer2TrafficMappingInfoList_t));
+            f1ap_iPtolayer2TrafficMappingInfo_Item_t this_ip2l2_item;
+
+            for(i=0; i < traffic_mapping_info.iPtolayer2TrafficMappingInfo.add_length; i++){
+              this_ip2l2_item = traffic_mapping_info.iPtolayer2TrafficMappingInfo.iPtolayer2TrafficMappingInfoToAdd[i];
+              asn1cSequenceAdd(iPToL2Info->iPtolayer2TrafficMappingInfoToAdd->list, F1AP_IPtolayer2TrafficMappingInfo_Item_t, iPToL2Item);
+              // mappingInformationIndex
+              NR_MAPPINGINFORMATIONINDEX_TO_BIT_STRING(this_ip2l2_item.mappingInformationIndex, &iPToL2Item->mappingInformationIndex);
+              
+              // iPHeaderInformation
+              /* Only IPv4 implemented for now, 
+              missing IPv6 address and IPv6 prefix */
+              if(this_ip2l2_item.iPHeaderInformation.destinationIABTNLAddress_type == ipv4Address){
+                iPToL2Item->iPHeaderInformation.destinationIABTNLAddress.present = F1AP_IABTNLAddress_PR_iPv4Address;
+                IABTNL_ADRESS_IPv4_TO_BIT_STRING(this_ip2l2_item.iPHeaderInformation.destinationIABTNLAddress.iPv4Address, 
+                                                &iPToL2Item->iPHeaderInformation.destinationIABTNLAddress.choice.iPv4Address);
+              }
+
+              if(this_ip2l2_item.iPHeaderInformation.infoList_length > 0){
+                iPToL2Item->iPHeaderInformation.dsInformationList = calloc(this_ip2l2_item.iPHeaderInformation.infoList_length, sizeof(F1AP_DSCP_t));
+                for(int j = 0; j < this_ip2l2_item.iPHeaderInformation.infoList_length; j++){
+                  asn1cSequenceAdd(iPToL2Item->iPHeaderInformation.dsInformationList->list, F1AP_DSCP_t, dscp);
+                  // Not sure if this is correct
+                  DSCP_TO_BIT_STRING(this_ip2l2_item.iPHeaderInformation.dsInformationList[j], &(*dscp));
+                }
+              }
+              /*
+              if(this_ip2l2_item.iPHeaderInformation.iPv6FlowLabel != NULL){
+                // TODO
+              }
+              */
+
+              //bhInfo
+              if(this_ip2l2_item.bHInfo.is_bAProutingID_set){
+                iPToL2Item->bHInfo.bAProutingID = calloc(1, sizeof(F1AP_BAPRoutingID_t));
+                NR_BAPADDRESS_TO_BIT_STRING(this_ip2l2_item.bHInfo.bAProutingID.bAPAddress, &iPToL2Item->bHInfo.bAProutingID->bAPAddress);
+                NR_BAPPATHID_TO_BIT_STRING(this_ip2l2_item.bHInfo.bAProutingID.bAPPathID, &iPToL2Item->bHInfo.bAProutingID->bAPPathID);
+              }
+
+              if(this_ip2l2_item.bHInfo.egressList_length > 0){
+                iPToL2Item->bHInfo.egressBHRLCCHList = calloc(this_ip2l2_item.bHInfo.egressList_length, sizeof(F1AP_EgressBHRLCCHItem_t));
+                for(int j = 0; j < this_ip2l2_item.bHInfo.egressList_length; j++){
+                  asn1cSequenceAdd(iPToL2Item->bHInfo.egressBHRLCCHList->list, F1AP_EgressBHRLCCHItem_t, egressLink);
+                  NR_BAPADDRESS_TO_BIT_STRING(this_ip2l2_item.bHInfo.egressBHRLCCHList[j].nextHopBAPAddress, &egressLink->nextHopBAPAddress);
+                  NR_BHRLCCHANNELID_TO_BIT_STRING(this_ip2l2_item.bHInfo.egressBHRLCCHList[j].bHRLCChannelID, &egressLink->bHRLCChannelID);
+                }
+              }
+            }
+          } 
+
+          if(traffic_mapping_info.iPtolayer2TrafficMappingInfo.remove_length > 0){            
+            iPToL2Info->iPtolayer2TrafficMappingInfoToRemove = calloc(traffic_mapping_info.iPtolayer2TrafficMappingInfo.remove_length, sizeof(F1AP_MappingInformationIndex_t));           
+
+            for(int i = 0; i < traffic_mapping_info.iPtolayer2TrafficMappingInfo.remove_length; i++){
+              asn1cSequenceAdd(iPToL2Info->iPtolayer2TrafficMappingInfoToRemove->list, F1AP_MappingInformationIndex_t, iPToL2RemoveIndex); 
+              NR_MAPPINGINFORMATIONINDEX_TO_BIT_STRING(traffic_mapping_info.iPtolayer2TrafficMappingInfo.iPtolayer2TrafficMappingInfoToRemove[i],
+                                                      &(*iPToL2RemoveIndex));
+
+            }
+          }
+
+        }          
+
+        // bAPlayerBHRLCchannelMappingInfo
+        else if (traffic_mapping_info.type == mapping_info_bAPlayerBHRLCchannelMappingInfo){
+          bhchs_toBeSetupMod_item->trafficMappingInfo->present = F1AP_TrafficMappingInfo_PR_bAPlayerBHRLCchannelMappingInfo;
+          asn1cCalloc(bhchs_toBeSetupMod_item->trafficMappingInfo->choice.bAPlayerBHRLCchannelMappingInfo, bapBHInfo);
+          
+          if(traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.add_length > 0){
+
+            bapBHInfo->bAPlayerBHRLCchannelMappingInfoToAdd = calloc(traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.add_length, sizeof(F1AP_BAPlayerBHRLCchannelMappingInfo_Item_t));
+
+            for(i=0; i < traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.add_length; i++){
+              asn1cSequenceAdd(bapBHInfo->bAPlayerBHRLCchannelMappingInfoToAdd->list, F1AP_BAPlayerBHRLCchannelMappingInfo_Item_t, bapBHItem);
+              NR_MAPPINGINFORMATIONINDEX_TO_BIT_STRING(traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.bAPlayerBHRLCchannelMappingInfoToAdd[i].mappingInformationIndex,
+                                                      &bapBHItem->mappingInformationIndex );
+              
+              // Won't use value 0 for IDs, meaning that 0 will be the value used for "not set"
+              if(traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.bAPlayerBHRLCchannelMappingInfoToAdd[i].priorHopBAPAddress == 0){
+                bapBHItem->priorHopBAPAddress = calloc(1, sizeof(F1AP_BAPAddress_t));
+                NR_BAPADDRESS_TO_BIT_STRING(traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.bAPlayerBHRLCchannelMappingInfoToAdd[i].priorHopBAPAddress,
+                                            &(*bapBHItem->priorHopBAPAddress));
+              }
+
+              if(traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.bAPlayerBHRLCchannelMappingInfoToAdd[i].ingressbHRLCChannelID == 0){
+                bapBHItem->ingressbHRLCChannelID = calloc(1, sizeof(F1AP_BHRLCChannelID_t));
+                NR_BHRLCCHANNELID_TO_BIT_STRING(traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.bAPlayerBHRLCchannelMappingInfoToAdd[i].ingressbHRLCChannelID,
+                                                &(*bapBHItem->ingressbHRLCChannelID));
+              }
+
+              if(traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.bAPlayerBHRLCchannelMappingInfoToAdd[i].nextHopBAPAddress == 0){
+                bapBHItem->nextHopBAPAddress = calloc(1, sizeof(F1AP_BAPAddress_t));
+                NR_BAPADDRESS_TO_BIT_STRING(traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.bAPlayerBHRLCchannelMappingInfoToAdd[i].nextHopBAPAddress,
+                                            &(*bapBHItem->nextHopBAPAddress));
+              }
+
+              if(traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.bAPlayerBHRLCchannelMappingInfoToAdd[i].egressbHRLCChannelID == 0){
+                bapBHItem->egressbHRLCChannelID = calloc(1, sizeof(F1AP_BHRLCChannelID_t));
+                NR_BHRLCCHANNELID_TO_BIT_STRING(traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.bAPlayerBHRLCchannelMappingInfoToAdd[i].egressbHRLCChannelID,
+                                                &(*bapBHItem->egressbHRLCChannelID));
+              }
+              
+            }
+          }
+
+          if(traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.remove_length > 0){
+
+            bapBHInfo->bAPlayerBHRLCchannelMappingInfoToRemove = calloc(traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.remove_length,  sizeof(F1AP_MappingInformationIndex_t));
+
+            for(int i = 0; i < traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.remove_length; i++){
+              asn1cSequenceAdd(bapBHInfo->bAPlayerBHRLCchannelMappingInfoToRemove->list, F1AP_MappingInformationIndex_t, bapBHRemoveIndex);
+              NR_MAPPINGINFORMATIONINDEX_TO_BIT_STRING(traffic_mapping_info.bAPlayerBHRLCchannelMappingInfo.bAPlayerBHRLCchannelMappingInfoToRemove[i],
+                                                      &(*bapBHRemoveIndex));
+            }
+          }
+        }
+        
+        /*
+        ...
+        */
+      }
+    }
+  }
+  /* [IAB] end */
+  
+
   /* encode */
   if (f1ap_encode_pdu(&pdu, &buffer, &len) < 0) {
     LOG_E(F1AP, "Failed to encode F1 UE CONTEXT_MODIFICATION REQUEST\n");
@@ -1596,118 +1826,118 @@ int CU_handle_UE_CONTEXT_MODIFICATION_RESPONSE(instance_t instance, sctp_assoc_t
   container = &pdu->choice.successfulOutcome->value.choice.UEContextModificationResponse;
   int i;
 
-    /* GNB_CU_UE_F1AP_ID */
-    F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
-                               F1AP_ProtocolIE_ID_id_gNB_CU_UE_F1AP_ID, true);
-    f1ap_ue_context_modification_resp->gNB_CU_ue_id = ie->value.choice.GNB_CU_UE_F1AP_ID;
+  /* GNB_CU_UE_F1AP_ID */
+  F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
+                              F1AP_ProtocolIE_ID_id_gNB_CU_UE_F1AP_ID, true);
+  f1ap_ue_context_modification_resp->gNB_CU_ue_id = ie->value.choice.GNB_CU_UE_F1AP_ID;
 
-    LOG_D(F1AP, "f1ap_ue_context_modif_resp->gNB_CU_ue_id is: %d \n", f1ap_ue_context_modification_resp->gNB_CU_ue_id);
+  LOG_D(F1AP, "f1ap_ue_context_modification_resp->gNB_CU_ue_id is: %d \n", f1ap_ue_context_modification_resp->gNB_CU_ue_id);
 
-    /* GNB_DU_UE_F1AP_ID */
-    F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
-                               F1AP_ProtocolIE_ID_id_gNB_DU_UE_F1AP_ID, true);
-    f1ap_ue_context_modification_resp->gNB_DU_ue_id = ie->value.choice.GNB_DU_UE_F1AP_ID;
+  /* GNB_DU_UE_F1AP_ID */
+  F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
+                              F1AP_ProtocolIE_ID_id_gNB_DU_UE_F1AP_ID, true);
+  f1ap_ue_context_modification_resp->gNB_DU_ue_id = ie->value.choice.GNB_DU_UE_F1AP_ID;
 
-    LOG_D(F1AP, "f1ap_ue_context_modification_resp->gNB_DU_ue_id is: %d \n", f1ap_ue_context_modification_resp->gNB_DU_ue_id);
+  LOG_D(F1AP, "f1ap_ue_context_modification_resp->gNB_DU_ue_id is: %d \n", f1ap_ue_context_modification_resp->gNB_DU_ue_id);
 
-    // DUtoCURRCInformation
-    F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
-                               F1AP_ProtocolIE_ID_id_DUtoCURRCInformation, false);
-    if(ie!=NULL){
-      f1ap_ue_context_modification_resp->du_to_cu_rrc_information = (du_to_cu_rrc_information_t *)calloc(1, sizeof(du_to_cu_rrc_information_t));
-      f1ap_ue_context_modification_resp->du_to_cu_rrc_information->cellGroupConfig = (uint8_t *)calloc(1,ie->value.choice.DUtoCURRCInformation.cellGroupConfig.size);
+  // DUtoCURRCInformation
+  F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
+                              F1AP_ProtocolIE_ID_id_DUtoCURRCInformation, false);
+  if(ie!=NULL){
+    f1ap_ue_context_modification_resp->du_to_cu_rrc_information = (du_to_cu_rrc_information_t *)calloc(1, sizeof(du_to_cu_rrc_information_t));
+    f1ap_ue_context_modification_resp->du_to_cu_rrc_information->cellGroupConfig = (uint8_t *)calloc(1,ie->value.choice.DUtoCURRCInformation.cellGroupConfig.size);
 
-      memcpy(f1ap_ue_context_modification_resp->du_to_cu_rrc_information->cellGroupConfig, ie->value.choice.DUtoCURRCInformation.cellGroupConfig.buf, ie->value.choice.DUtoCURRCInformation.cellGroupConfig.size);
-      f1ap_ue_context_modification_resp->du_to_cu_rrc_information->cellGroupConfig_length = ie->value.choice.DUtoCURRCInformation.cellGroupConfig.size;
+    memcpy(f1ap_ue_context_modification_resp->du_to_cu_rrc_information->cellGroupConfig, ie->value.choice.DUtoCURRCInformation.cellGroupConfig.buf, ie->value.choice.DUtoCURRCInformation.cellGroupConfig.size);
+    f1ap_ue_context_modification_resp->du_to_cu_rrc_information->cellGroupConfig_length = ie->value.choice.DUtoCURRCInformation.cellGroupConfig.size;
+  }
+
+  // DRBs_SetupMod_List
+  F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
+                              F1AP_ProtocolIE_ID_id_DRBs_SetupMod_List, false);
+  if(ie!=NULL){
+    f1ap_ue_context_modification_resp->drbs_to_be_setup_length = ie->value.choice.DRBs_SetupMod_List.list.count;
+    f1ap_ue_context_modification_resp->drbs_to_be_setup = calloc(f1ap_ue_context_modification_resp->drbs_to_be_setup_length,
+        sizeof(f1ap_drb_to_be_setup_t));
+    AssertFatal(f1ap_ue_context_modification_resp->drbs_to_be_setup,
+              "could not allocate memory for f1ap_ue_context_setup_resp->drbs_setup\n");
+    for (i = 0; i < f1ap_ue_context_modification_resp->drbs_to_be_setup_length; ++i) {
+      f1ap_drb_to_be_setup_t *drb_p = &f1ap_ue_context_modification_resp->drbs_to_be_setup[i];
+      F1AP_DRBs_SetupMod_Item_t *drbs_setupmod_item_p;
+      drbs_setupmod_item_p = &((F1AP_DRBs_SetupMod_ItemIEs_t *)ie->value.choice.DRBs_SetupMod_List.list.array[i])->value.choice.DRBs_SetupMod_Item;
+      drb_p->drb_id = drbs_setupmod_item_p->dRBID;
+      // TODO in the following, assume only one UP UL TNL is present.
+        // this matches/assumes OAI CU/DU implementation, can be up to 2!
+      drb_p->up_dl_tnl_length = 1;
+      AssertFatal(drbs_setupmod_item_p->dLUPTNLInformation_ToBeSetup_List.list.count > 0,
+          "no DL UP TNL Information in DRBs to be Setup list\n");
+      F1AP_DLUPTNLInformation_ToBeSetup_Item_t *dl_up_tnl_info_p = (F1AP_DLUPTNLInformation_ToBeSetup_Item_t *)drbs_setupmod_item_p->dLUPTNLInformation_ToBeSetup_List.list.array[0];
+      F1AP_GTPTunnel_t *dl_up_tnl0 = dl_up_tnl_info_p->dLUPTNLInformation.choice.gTPTunnel;
+      BIT_STRING_TO_TRANSPORT_LAYER_ADDRESS_IPv4(&dl_up_tnl0->transportLayerAddress, drb_p->up_dl_tnl[0].tl_address);
+      OCTET_STRING_TO_UINT32(&dl_up_tnl0->gTP_TEID, drb_p->up_dl_tnl[0].teid);
+      GtpuUpdateTunnelOutgoingAddressAndTeid(getCxt(instance)->gtpInst,
+                    f1ap_ue_context_modification_resp->gNB_CU_ue_id,
+                    (ebi_t)drbs_setupmod_item_p->dRBID,
+                    drb_p->up_dl_tnl[0].tl_address,
+                    drb_p->up_dl_tnl[0].teid);
+    }
+  }
+  // SRBs_FailedToBeSetupMod_List
+  F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
+                              F1AP_ProtocolIE_ID_id_SRBs_FailedToBeSetupMod_List, false);
+  if(ie!=NULL){
+    f1ap_ue_context_modification_resp->srbs_failed_to_be_setup_length = ie->value.choice.SRBs_FailedToBeSetupMod_List.list.count;
+    f1ap_ue_context_modification_resp->srbs_failed_to_be_setup = calloc(f1ap_ue_context_modification_resp->srbs_failed_to_be_setup_length,
+        sizeof(f1ap_rb_failed_to_be_setup_t));
+    AssertFatal(f1ap_ue_context_modification_resp->srbs_failed_to_be_setup,
+        "could not allocate memory for f1ap_ue_context_setup_resp->srbs_failed_to_be_setup\n");
+    for (i = 0; i < f1ap_ue_context_modification_resp->srbs_failed_to_be_setup_length; ++i) {
+      f1ap_rb_failed_to_be_setup_t *srb_p = &f1ap_ue_context_modification_resp->srbs_failed_to_be_setup[i];
+      srb_p->rb_id = ((F1AP_SRBs_FailedToBeSetupMod_Item_t *)ie->value.choice.SRBs_FailedToBeSetupMod_List.list.array[i])->sRBID;
     }
 
-    // DRBs_SetupMod_List
-    F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
-                               F1AP_ProtocolIE_ID_id_DRBs_SetupMod_List, false);
-    if(ie!=NULL){
-      f1ap_ue_context_modification_resp->drbs_to_be_setup_length = ie->value.choice.DRBs_SetupMod_List.list.count;
-      f1ap_ue_context_modification_resp->drbs_to_be_setup = calloc(f1ap_ue_context_modification_resp->drbs_to_be_setup_length,
-          sizeof(f1ap_drb_to_be_setup_t));
-      AssertFatal(f1ap_ue_context_modification_resp->drbs_to_be_setup,
-                "could not allocate memory for f1ap_ue_context_setup_resp->drbs_setup\n");
-      for (i = 0; i < f1ap_ue_context_modification_resp->drbs_to_be_setup_length; ++i) {
-        f1ap_drb_to_be_setup_t *drb_p = &f1ap_ue_context_modification_resp->drbs_to_be_setup[i];
-        F1AP_DRBs_SetupMod_Item_t *drbs_setupmod_item_p;
-        drbs_setupmod_item_p = &((F1AP_DRBs_SetupMod_ItemIEs_t *)ie->value.choice.DRBs_SetupMod_List.list.array[i])->value.choice.DRBs_SetupMod_Item;
-        drb_p->drb_id = drbs_setupmod_item_p->dRBID;
-        // TODO in the following, assume only one UP UL TNL is present.
-         // this matches/assumes OAI CU/DU implementation, can be up to 2!
-        drb_p->up_dl_tnl_length = 1;
-        AssertFatal(drbs_setupmod_item_p->dLUPTNLInformation_ToBeSetup_List.list.count > 0,
-            "no DL UP TNL Information in DRBs to be Setup list\n");
-        F1AP_DLUPTNLInformation_ToBeSetup_Item_t *dl_up_tnl_info_p = (F1AP_DLUPTNLInformation_ToBeSetup_Item_t *)drbs_setupmod_item_p->dLUPTNLInformation_ToBeSetup_List.list.array[0];
-        F1AP_GTPTunnel_t *dl_up_tnl0 = dl_up_tnl_info_p->dLUPTNLInformation.choice.gTPTunnel;
-        BIT_STRING_TO_TRANSPORT_LAYER_ADDRESS_IPv4(&dl_up_tnl0->transportLayerAddress, drb_p->up_dl_tnl[0].tl_address);
-        OCTET_STRING_TO_UINT32(&dl_up_tnl0->gTP_TEID, drb_p->up_dl_tnl[0].teid);
-        GtpuUpdateTunnelOutgoingAddressAndTeid(getCxt(instance)->gtpInst,
-                     f1ap_ue_context_modification_resp->gNB_CU_ue_id,
-                     (ebi_t)drbs_setupmod_item_p->dRBID,
-                     drb_p->up_dl_tnl[0].tl_address,
-                     drb_p->up_dl_tnl[0].teid);
-      }
+  }
+  // DRBs_FailedToBeSetupMod_List
+  F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
+                              F1AP_ProtocolIE_ID_id_DRBs_FailedToBeSetupMod_List, false);
+  if(ie!=NULL){
+    f1ap_ue_context_modification_resp->drbs_failed_to_be_setup_length = ie->value.choice.DRBs_FailedToBeSetupMod_List.list.count;
+    f1ap_ue_context_modification_resp->drbs_failed_to_be_setup = calloc(f1ap_ue_context_modification_resp->drbs_failed_to_be_setup_length,
+        sizeof(f1ap_rb_failed_to_be_setup_t));
+    AssertFatal(f1ap_ue_context_modification_resp->drbs_failed_to_be_setup,
+        "could not allocate memory for f1ap_ue_context_setup_resp->drbs_failed_to_be_setup\n");
+    for (i = 0; i < f1ap_ue_context_modification_resp->drbs_failed_to_be_setup_length; ++i) {
+      f1ap_rb_failed_to_be_setup_t *drb_p = &f1ap_ue_context_modification_resp->drbs_failed_to_be_setup[i];
+      drb_p->rb_id = ((F1AP_DRBs_FailedToBeSetupMod_Item_t *)ie->value.choice.DRBs_FailedToBeSetupMod_List.list.array[i])->dRBID;
     }
-    // SRBs_FailedToBeSetupMod_List
-    F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
-                               F1AP_ProtocolIE_ID_id_SRBs_FailedToBeSetupMod_List, false);
-    if(ie!=NULL){
-      f1ap_ue_context_modification_resp->srbs_failed_to_be_setup_length = ie->value.choice.SRBs_FailedToBeSetupMod_List.list.count;
-      f1ap_ue_context_modification_resp->srbs_failed_to_be_setup = calloc(f1ap_ue_context_modification_resp->srbs_failed_to_be_setup_length,
-          sizeof(f1ap_rb_failed_to_be_setup_t));
-      AssertFatal(f1ap_ue_context_modification_resp->srbs_failed_to_be_setup,
-          "could not allocate memory for f1ap_ue_context_setup_resp->srbs_failed_to_be_setup\n");
-      for (i = 0; i < f1ap_ue_context_modification_resp->srbs_failed_to_be_setup_length; ++i) {
-        f1ap_rb_failed_to_be_setup_t *srb_p = &f1ap_ue_context_modification_resp->srbs_failed_to_be_setup[i];
-        srb_p->rb_id = ((F1AP_SRBs_FailedToBeSetupMod_Item_t *)ie->value.choice.SRBs_FailedToBeSetupMod_List.list.array[i])->sRBID;
-      }
+  }
 
-    }
-    // DRBs_FailedToBeSetupMod_List
-    F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
-                               F1AP_ProtocolIE_ID_id_DRBs_FailedToBeSetupMod_List, false);
-    if(ie!=NULL){
-      f1ap_ue_context_modification_resp->drbs_failed_to_be_setup_length = ie->value.choice.DRBs_FailedToBeSetupMod_List.list.count;
-      f1ap_ue_context_modification_resp->drbs_failed_to_be_setup = calloc(f1ap_ue_context_modification_resp->drbs_failed_to_be_setup_length,
-          sizeof(f1ap_rb_failed_to_be_setup_t));
-      AssertFatal(f1ap_ue_context_modification_resp->drbs_failed_to_be_setup,
-          "could not allocate memory for f1ap_ue_context_setup_resp->drbs_failed_to_be_setup\n");
-      for (i = 0; i < f1ap_ue_context_modification_resp->drbs_failed_to_be_setup_length; ++i) {
-        f1ap_rb_failed_to_be_setup_t *drb_p = &f1ap_ue_context_modification_resp->drbs_failed_to_be_setup[i];
-        drb_p->rb_id = ((F1AP_DRBs_FailedToBeSetupMod_Item_t *)ie->value.choice.DRBs_FailedToBeSetupMod_List.list.array[i])->dRBID;
-      }
-    }
+  // SCell_FailedtoSetupMod_List
+  F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
+                              F1AP_ProtocolIE_ID_id_SCell_FailedtoSetupMod_List, false);
+  if(ie!=NULL){
+    LOG_E (F1AP, "Not supporting handling of SCell_FailedtoSetupMod_List \n");
+  }
 
-    // SCell_FailedtoSetupMod_List
-    F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
-                               F1AP_ProtocolIE_ID_id_SCell_FailedtoSetupMod_List, false);
-    if(ie!=NULL){
-      LOG_E (F1AP, "Not supporting handling of SCell_FailedtoSetupMod_List \n");
+  // SRBs_Setup_List
+  F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
+      F1AP_ProtocolIE_ID_id_SRBs_SetupMod_List, false);
+  if(ie!=NULL){
+    f1ap_ue_context_modification_resp->srbs_to_be_setup_length = ie->value.choice.SRBs_SetupMod_List.list.count;
+    f1ap_ue_context_modification_resp->srbs_to_be_setup = calloc(f1ap_ue_context_modification_resp->srbs_to_be_setup_length,
+        sizeof(f1ap_srb_to_be_setup_t));
+    AssertFatal(f1ap_ue_context_modification_resp->srbs_to_be_setup,
+        "could not allocate memory for f1ap_ue_context_setup_resp->drbs_setup\n");
+    for (i = 0; i < f1ap_ue_context_modification_resp->srbs_to_be_setup_length; ++i) {
+      f1ap_srb_to_be_setup_t *srb_p = &f1ap_ue_context_modification_resp->srbs_to_be_setup[i];
+      F1AP_SRBs_SetupMod_Item_t *srbs_setup_item_p;
+      srbs_setup_item_p = &((F1AP_SRBs_SetupMod_ItemIEs_t *)ie->value.choice.SRBs_SetupMod_List.list.array[i])->value.choice.SRBs_SetupMod_Item;
+      srb_p->srb_id = srbs_setup_item_p->sRBID;
+      srb_p->lcid = srbs_setup_item_p->lCID;
     }
+  }
 
-    // SRBs_Setup_List
-    F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationResponseIEs_t, ie, container,
-        F1AP_ProtocolIE_ID_id_SRBs_SetupMod_List, false);
-    if(ie!=NULL){
-      f1ap_ue_context_modification_resp->srbs_to_be_setup_length = ie->value.choice.SRBs_SetupMod_List.list.count;
-      f1ap_ue_context_modification_resp->srbs_to_be_setup = calloc(f1ap_ue_context_modification_resp->srbs_to_be_setup_length,
-          sizeof(f1ap_srb_to_be_setup_t));
-      AssertFatal(f1ap_ue_context_modification_resp->srbs_to_be_setup,
-          "could not allocate memory for f1ap_ue_context_setup_resp->drbs_setup\n");
-      for (i = 0; i < f1ap_ue_context_modification_resp->srbs_to_be_setup_length; ++i) {
-        f1ap_srb_to_be_setup_t *srb_p = &f1ap_ue_context_modification_resp->srbs_to_be_setup[i];
-        F1AP_SRBs_SetupMod_Item_t *srbs_setup_item_p;
-        srbs_setup_item_p = &((F1AP_SRBs_SetupMod_ItemIEs_t *)ie->value.choice.SRBs_SetupMod_List.list.array[i])->value.choice.SRBs_SetupMod_Item;
-        srb_p->srb_id = srbs_setup_item_p->sRBID;
-        srb_p->lcid = srbs_setup_item_p->lCID;
-      }
-    }
-
-    itti_send_msg_to_task(TASK_RRC_GNB, instance, msg_p);
-    return 0;
+  itti_send_msg_to_task(TASK_RRC_GNB, instance, msg_p);
+  return 0;
 }
 
 int CU_handle_UE_CONTEXT_MODIFICATION_FAILURE(instance_t instance, sctp_assoc_t assoc_id, uint32_t stream, F1AP_F1AP_PDU_t *pdu)

openair2/F1AP/f1ap_du_interface_management.c

@@ -36,6 +36,7 @@
 #include "f1ap_du_interface_management.h"
 #include "openair2/LAYER2/NR_MAC_gNB/mac_rrc_dl_handler.h"
 #include "assertions.h"
+#include "openair2/LAYER2/BAP/bap_oai_api.h"
 
 #include "GNB_APP/gnb_paramdef.h"
 
@@ -316,6 +317,16 @@ int DU_send_F1_SETUP_REQUEST(sctp_assoc_t assoc_id, f1ap_setup_req_t *setup_req)
   for (int i = 0; i < 3; ++i)
     os->buf[i] = setup_req->rrc_ver[i];
   ie2->value.choice.RRC_Version.iE_Extensions = (struct F1AP_ProtocolExtensionContainer*)p;
+
+  /* optional */
+  /* c6. BAPAddress*/
+  if (setup_req->bap_address != 0) {
+    asn1cSequenceAdd(f1Setup->protocolIEs.list, F1AP_F1SetupRequestIEs_t, bap_addr);
+    bap_addr->id                        = F1AP_ProtocolIE_ID_id_BAPAddress;
+    bap_addr->criticality               = F1AP_Criticality_ignore;
+    bap_addr->value.present             = F1AP_F1SetupRequestIEs__value_PR_BAPAddress;
+    NR_BAPADDRESS_TO_BIT_STRING(setup_req->bap_address, &bap_addr->value.choice.BAPAddress);
+  }
   
   /* encode */
   if (f1ap_encode_pdu(&pdu, &buffer, &len) < 0) {
@@ -370,6 +381,16 @@ int DU_handle_F1_SETUP_RESPONSE(instance_t instance, sctp_assoc_t assoc_id, uint
         LOG_D(F1AP, "F1AP: F1Setup-Resp: gNB_CU_name %s\n", resp.gNB_CU_name);
         break;
 
+      case F1AP_ProtocolIE_ID_id_BAPAddress:
+        AssertFatal(ie->criticality == F1AP_Criticality_ignore,
+                    "ie->criticality != F1AP_Criticality_ignore\n");
+        AssertFatal(ie->value.present == F1AP_F1SetupResponseIEs__value_PR_BAPAddress,
+                    "ie->value.present != F1AP_F1SetupResponseIEs__value_PR_BAPAddress\n");
+        BIT_STRING_TO_NR_BAPADDRESS(&ie->value.choice.BAPAddress, resp.bap_address);
+        LOG_D(F1AP, "F1AP: F1Setup-Resp: BAPAddress %d\n", resp.bap_address);
+        init_bap_entity(resp.bap_address, true);
+        break;
+
       case F1AP_ProtocolIE_ID_id_GNB_CU_RRC_Version:
         AssertFatal(ie->criticality == F1AP_Criticality_reject,
                     "ie->criticality != F1AP_Criticality_reject\n");

openair2/F1AP/f1ap_du_task.c

@@ -102,6 +102,7 @@ void *F1AP_DU_task(void *arg) {
     instance_t myInstance=ITTI_MSG_DESTINATION_INSTANCE(msg);
     sctp_assoc_t assoc_id = getCxt(0) != NULL ? getCxt(0)->du.assoc_id : 0;
     LOG_D(F1AP, "DU Task Received %s for instance %ld: sending SCTP messages via assoc_id %d\n", ITTI_MSG_NAME(msg), myInstance, assoc_id);
+    LOG_D(F1AP, "Current Received message %d\n", msg->ittiMsgHeader.messageId);
     switch (ITTI_MSG_ID(msg)) {
       case F1AP_SETUP_REQ:
         AssertFatal(false, "the F1AP_SETUP_REQ should not be received; use the F1AP_DU_REGISTER_REQ instead\n");

openair2/F1AP/f1ap_du_ue_context_management.c

@@ -1074,6 +1074,50 @@ int DU_handle_UE_CONTEXT_MODIFICATION_REQUEST(instance_t instance, sctp_assoc_t
     }
   }
 
+  /* [IAB] related params */
+  F1AP_UEContextModificationRequestIEs_t *ieBhrlc;
+  F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextModificationRequestIEs_t, ieBhrlc, container,
+                   F1AP_ProtocolIE_ID_id_BHChannels_ToBeSetupMod_List, false);
+  if(ieBhrlc != NULL){
+    f1ap_ue_context_modification_req->bhchannels_to_be_setup_length = ieBhrlc->value.choice.BHChannels_ToBeSetupMod_List.list.count;
+    f1ap_ue_context_modification_req->bhchannels_to_be_setup = calloc(f1ap_ue_context_modification_req->bhchannels_to_be_setup_length,
+                                                              sizeof(f1ap_bhchannel_to_be_setup_t));
+    
+    AssertFatal(f1ap_ue_context_modification_req->bhchannels_to_be_setup,
+          "could not allocate memory for f1ap_ue_context_modification_req->bhchannels_to_be_setup\n");
+
+    for(i = 0; i < f1ap_ue_context_modification_req->bhchannels_to_be_setup_length; i++){
+      f1ap_bhchannel_to_be_setup_t *bhrlc_p = &f1ap_ue_context_modification_req->bhchannels_to_be_setup[i];
+      F1AP_BHChannels_ToBeSetupMod_Item_t *bhrlc_tobesetupmod_item_p =
+          &((F1AP_BHChannels_ToBeSetupMod_ItemIEs_t *)ieBhrlc->value.choice.BHChannels_ToBeSetupMod_List.list.array[i])->value.choice.BHChannels_ToBeSetupMod_Item;
+      BIT_STRING_TO_NR_BHRLCCHANNELID(&bhrlc_tobesetupmod_item_p->bHRLCChannelID, bhrlc_p->bHRLCChannelID);
+
+      switch (bhrlc_tobesetupmod_item_p->rLCmode) {
+      case F1AP_RLCMode_rlc_am:
+        bhrlc_p->rlc_mode = RLC_MODE_AM;
+        break;
+        /*
+      case F1AP_RLCMode_rlc_um:
+        bhrlc_p->rlc_mode = RLC_MODE_UM;
+        */
+      default:
+        bhrlc_p->rlc_mode = RLC_MODE_TM;
+        break;
+      }
+
+      if(bhrlc_tobesetupmod_item_p->bAPCtrlPDUChannel == F1AP_BAPCtrlPDUChannel_true){
+        bhrlc_p->is_bap_Ctrl_PDU_Channel = true;
+      }
+
+      if(bhrlc_tobesetupmod_item_p->trafficMappingInfo != NULL){
+        bhrlc_p->is_trafficMappingInfo_set = true;
+        // TODO: Traffic mapping info configurations
+      }else{
+        bhrlc_p->is_trafficMappingInfo_set = false;
+      }
+    }
+  }
+  /* [IAB] end */
   ue_context_modification_request(f1ap_ue_context_modification_req);
   return 0;
 }

openair2/GNB_APP/gnb_config.c

@@ -91,6 +91,7 @@
 #include "RRC/NR/nr_rrc_extern.h"
 #include "openair2/LAYER2/nr_pdcp/nr_pdcp.h"
 #include "nfapi/oai_integration/vendor_ext.h"
+#include "openair2/LAYER2/BAP/bap_oai_api.h"
 
 extern uint16_t sf_ahead;
 
@@ -707,7 +708,9 @@ void RCconfig_verify(configmodule_interface_t *cfg, ngran_node_t node_type)
 
     verify_section_notset(cfg, GNB_CONFIG_STRING_GNB_LIST ".", GNB_CONFIG_STRING_AMF_IP_ADDRESS);
     verify_section_notset(cfg, NULL, CONFIG_STRING_SECURITY);
-  } // else nothing to be checked
+  } // Maybe add new things for Node_DU and Donor_DU in the future
+   
+  // else nothing to be checked
 
   /* other possible verifications: PNF, VNF, CU-CP, CU-UP, ...? */
 }
@@ -1035,6 +1038,7 @@ static NR_ServingCellConfig_t *get_scd_config(configmodule_interface_t *cfg)
 
 static int read_du_cell_info(configmodule_interface_t *cfg,
                              bool separate_du,
+                             /*bool separate_iab_du,*/
                              uint32_t *gnb_id,
                              uint64_t *gnb_du_id,
                              char **name,
@@ -1078,7 +1082,13 @@ static int read_du_cell_info(configmodule_interface_t *cfg,
   if (separate_du) {
     AssertFatal(config_isparamset(GNBParamList.paramarray[0], GNB_GNB_DU_ID_IDX), "%s is not defined in configuration file\n", GNB_CONFIG_STRING_GNB_DU_ID);
     *gnb_du_id = *GNBParamList.paramarray[0][GNB_GNB_DU_ID_IDX].u64ptr;
-  } else {
+  } 
+  /*else if (separate_iab_du) {
+    AssertFatal(config_isparamset(GNBParamList.paramarray[0], GNB_GNB_DU_ID_IDX), "%s is not defined in configuration file\n", GNB_CONFIG_STRING_GNB_DU_ID);
+    *gnb_du_id = *GNBParamList.paramarray[0][GNB_GNB_DU_ID_IDX].u64ptr;
+    *bap_address = *GNBParamList.paramarray[0][GNB_BAP_ADDRESS_IDX].u16ptr;
+    
+  }*/ else {
     AssertFatal(!config_isparamset(GNBParamList.paramarray[0], GNB_GNB_DU_ID_IDX),
                 "%s should not be defined in configuration file for monolithic gNB\n",
                 GNB_CONFIG_STRING_GNB_DU_ID);
@@ -1103,8 +1113,10 @@ static int read_du_cell_info(configmodule_interface_t *cfg,
   return 1;
 }
 
-static f1ap_setup_req_t *RC_read_F1Setup(uint64_t id,
+static f1ap_setup_req_t *RC_read_F1Setup(/*bool is_iab_du,*/
+                                         uint64_t id,
                                          const char *name,
+                                         /*uint16_t bap_address,*/
                                          const f1ap_served_cell_info_t *info,
                                          const NR_ServingCellConfigCommon_t *scc,
                                          NR_BCCH_BCH_Message_t *mib,
@@ -1114,18 +1126,39 @@ static f1ap_setup_req_t *RC_read_F1Setup(uint64_t id,
   AssertFatal(req != NULL, "out of memory\n");
   req->gNB_DU_id = id;
   req->gNB_DU_name = strdup(name);
+  /*if(is_iab_du){
+    req->bap_address = bap_address;
+  }*/
   req->num_cells_available = 1;
   req->cell[0].info = *info;
-  LOG_I(GNB_APP,
-        "F1AP: gNB idx %d gNB_DU_id %ld, gNB_DU_name %s, TAC %d MCC/MNC/length %d/%d/%d cellID %ld\n",
+
+  /*if (is_iab_du){
+    LOG_I(GNB_APP,
+        "F1AP: gNB idx %d gNB_DU_id %ld, gNB_DU_name %s, bap_address %d, TAC %d MCC/MNC/length %d/%d/%d cellID %ld\n",
         0,
         req->gNB_DU_id,
         req->gNB_DU_name,
+        req->bap_address,
         *req->cell[0].info.tac,
         req->cell[0].info.plmn.mcc,
         req->cell[0].info.plmn.mnc,
         req->cell[0].info.plmn.mnc_digit_length,
         req->cell[0].info.nr_cellid);
+    LOG_I(GNB_APP, "F1AP: Initializing BAP layer\n");
+    bool is_du = true;
+    nr_bap_layer_init(is_du);
+    */
+  LOG_I(GNB_APP,
+      "F1AP: gNB idx %d gNB_DU_id %ld, gNB_DU_name %s, TAC %d MCC/MNC/length %d/%d/%d cellID %ld\n",
+      0,
+      req->gNB_DU_id,
+      req->gNB_DU_name,
+      *req->cell[0].info.tac,
+      req->cell[0].info.plmn.mcc,
+      req->cell[0].info.plmn.mnc,
+      req->cell[0].info.plmn.mnc_digit_length,
+      req->cell[0].info.nr_cellid);
+  
 
   req->cell[0].info.nr_pci = *scc->physCellId;
   struct NR_FrequencyInfoDL *frequencyInfoDL = scc->downlinkConfigCommon->frequencyInfoDL;
@@ -1327,7 +1360,9 @@ void RCconfig_nr_macrlc(configmodule_interface_t *cfg)
     uint64_t gnb_du_id = 0;
     uint32_t gnb_id = 0;
     char *name = NULL;
+    // uint16_t bap_address = 0;
     f1ap_served_cell_info_t info;
+    // read_du_cell_info(cfg, NODE_IS_DU(node_type), &gnb_id, &gnb_du_id, &name, &bap_address, &info, 1);
     read_du_cell_info(cfg, NODE_IS_DU(node_type), &gnb_id, &gnb_du_id, &name, &info, 1);
 
     if (get_softmodem_params()->sa)
@@ -1337,6 +1372,7 @@ void RCconfig_nr_macrlc(configmodule_interface_t *cfg)
     // and store it at MAC for sending later
     NR_BCCH_BCH_Message_t *mib = RC.nrmac[0]->common_channels[0].mib;
     const NR_BCCH_DL_SCH_Message_t *sib1 = RC.nrmac[0]->common_channels[0].sib1;
+    //f1ap_setup_req_t *req = RC_read_F1Setup(NODE_IS_DU_IAB(node_type), gnb_du_id, name, bap_address, &info, scc, mib, sib1);
     f1ap_setup_req_t *req = RC_read_F1Setup(gnb_du_id, name, &info, scc, mib, sib1);
     AssertFatal(req != NULL, "could not read F1 Setup information\n");
     RC.nrmac[0]->f1_config.setup_req = req;
@@ -2254,7 +2290,13 @@ ngran_node_t get_node_type(void)
     RC.nb_nr_macrlc_inst = MacRLC_ParamList.numelt; 
     for (int j = 0; j < RC.nb_nr_macrlc_inst; j++) {
       if (strcmp(*(MacRLC_ParamList.paramarray[j][MACRLC_TRANSPORT_N_PREFERENCE_IDX].strptr), "f1") == 0) {
-        return ngran_gNB_DU; // MACRLCs present in config: it must be a DU
+        if (strstr(*(GNBParamList.paramarray[0][GNB_GNB_NAME_IDX].strptr), "Node") != NULL){
+          return ngran_gNB_IAB_node_DU;
+        } else if (strstr(*(GNBParamList.paramarray[0][GNB_GNB_NAME_IDX].strptr), "Donor") != NULL){
+          return ngran_gNB_IAB_donor_DU;
+        }else{
+          return ngran_gNB_DU;
+        }
       }
     }
   }

openair2/GNB_APP/gnb_paramdef.h

@@ -103,6 +103,7 @@ typedef enum {
 #define GNB_CONFIG_STRING_GNB_ID                        "gNB_ID"
 #define GNB_CONFIG_STRING_CELL_TYPE                     "cell_type"
 #define GNB_CONFIG_STRING_GNB_NAME                      "gNB_name"
+#define GNB_CONFIG_STRING_BAP_ADDRESS                   "bap_address"
 #define GNB_CONFIG_STRING_TRACKING_AREA_CODE            "tracking_area_code"
 #define GNB_CONFIG_STRING_MOBILE_COUNTRY_CODE_OLD       "mobile_country_code"
 #define GNB_CONFIG_STRING_MOBILE_NETWORK_CODE_OLD       "mobile_network_code"
@@ -173,6 +174,7 @@ typedef enum {
 {GNB_CONFIG_STRING_DRBS, GNB_CONFIG_HLP_STRING_DRBS,     0,            .iptr=NULL,  .defintval=1,                 TYPE_INT,       0},  \
 {GNB_CONFIG_STRING_GNB_DU_ID, GNB_CONFIG_HLP_GNB_DU_ID,   0,          .u64ptr=NULL, .defint64val=1,               TYPE_UINT64,    0},  \
 {GNB_CONFIG_STRING_GNB_CU_UP_ID, GNB_CONFIG_HLP_GNB_CU_UP_ID, 0,      .u64ptr=NULL, .defint64val=1,               TYPE_UINT64,    0},  \
+{GNB_CONFIG_STRING_BAP_ADDRESS,                  NULL,   0,           .uptr=NULL,   .defuintval=0,                TYPE_UINT,      0},  \
 }
 // clang-format on
 
@@ -205,8 +207,10 @@ typedef enum {
 #define GNB_FORCE256QAMOFF_IDX          25
 #define GNB_ENABLE_SDAP_IDX             26
 #define GNB_DRBS                        27
-#define GNB_GNB_DU_ID_IDX 28
-#define GNB_GNB_CU_UP_ID_IDX 29
+#define GNB_GNB_DU_ID_IDX               28
+#define GNB_GNB_CU_UP_ID_IDX            29
+// [IAB] bap_address
+#define GNB_BAP_ADDRESS_IDX             30
 
 #define TRACKING_AREA_CODE_OKRANGE {0x0001,0xFFFD}
 #define GNBPARAMS_CHECK {                                         \

openair2/LAYER2/BAP/bap_entity.c

@@ -0,0 +1,17 @@
+#include "bap_entity.h"
+
+bap_entity_t *new_bap_entity(uint16_t bap_address, bool is_du){
+  bap_entity_t *ret;
+  ret = calloc(1, sizeof(bap_entity_t));
+  if (ret == NULL) {
+    // Change to BAP log
+    LOG_E(RLC, "%s:%d:%s: out of memory\n", __FILE__, __LINE__, __FUNCTION__);
+    exit(1);
+  }
+  
+  if (pthread_mutex_init(&ret->lock, NULL)) abort();
+
+  ret->is_du = is_du;
+  ret->bap_address = bap_address;
+  return (bap_entity_t *)ret;
+}

openair2/LAYER2/BAP/bap_entity.h

@@ -0,0 +1,34 @@
+
+#include <stdint.h>
+#include <pthread.h>
+
+typedef struct{
+    uint16_t bap_address;
+    uint16_t bap_path_id;
+}bap_routing_id_t;
+
+typedef struct{
+    uint16_t priorHop_bap_address;
+    uint16_t ingress_bhch_ID;
+    uint16_t nextHop_bap_address;
+    uint16_t egress_bhch_ID;
+} bap_bhch_mapping_info_t;
+
+typedef struct bap_entity_t{
+    pthread_mutex_t lock;
+    bool is_du; // true if DU, false if MT
+    uint16_t bap_address;
+    bap_routing_id_t defaultUL_bap_routing_id;
+    uint16_t befaultUL_bh_rlc_channel_id;
+    enum{
+        PER_BH_RLC_Channel,
+        PER_ROUTING_ID,
+        BOTH
+    }flow_control_feedback_type;
+
+    // From BAPlayerBHRLCchannelMappingInfo
+    // Use mappingInformationIndex to navigate the list
+    bap_bhch_mapping_info_t *bhch_mapping_info_list;
+}bap_entity_t;
+
+bap_entity_t *new_bap_entity(uint16_t bap_address, bool is_du);

openair2/LAYER2/BAP/bap_oai_api.c

@@ -0,0 +1,223 @@
+/* from openair */
+#include "rlc.h"
+
+/* from nr rlc module */
+#include "openair2/LAYER2/nr_rlc/nr_rlc_asn1_utils.h"
+#include "openair2/LAYER2/nr_rlc/nr_rlc_ue_manager.h"
+#include "openair2/LAYER2/nr_rlc/nr_rlc_entity.h"
+#include "openair2/LAYER2/nr_rlc/nr_rlc_oai_api.h"
+#include "NR_RLC-BearerConfig.h"
+#include "NR_DRB-ToAddMod.h"
+#include "NR_DRB-ToAddModList.h"
+#include "NR_SRB-ToAddModList.h"
+#include "NR_DRB-ToReleaseList.h"
+#include "NR_CellGroupConfig.h"
+#include "NR_RLC-Config.h"
+#include "common/ran_context.h"
+#include "NR_UL-CCCH-Message.h"
+#include "conversions.h"
+#include "bap_oai_api.h"
+
+// Having trouble changing this to .h
+#include "bap_entity.c"
+
+extern RAN_CONTEXT_t RC;
+
+#include <executables/softmodem-common.h>
+
+static bap_entity_t *bap_entity;
+
+// Same as RLC?
+static void deliver_bap_sdu(void *_ue, nr_rlc_entity_t *entity, char *buf, int size)
+{
+  // TODO
+}
+
+static void successful_bap_delivery(void *_ue, nr_rlc_entity_t *entity, int sdu_id)
+{
+  // TODO
+}
+
+static void max_retx_reached(void *_ue, nr_rlc_entity_t *entity){
+  // TODO
+}
+
+static void add_bhch_um(int rnti, int bhch_id, const NR_BH_RLC_ChannelConfig_r16_t *rlc_bhchConfig)
+{
+  struct NR_RLC_Config *r = rlc_bhchConfig->rlc_Config_r16;
+
+  int sn_field_length;
+  int t_reassembly;
+
+  AssertFatal(bhch_id > 0 && bhch_id <= 32,
+              "Invalid bhch ID %d\n", bhch_id);
+
+  switch (r->present) {
+  case NR_RLC_Config_PR_um_Bi_Directional: {
+    struct NR_RLC_Config__um_Bi_Directional *um;
+    um = r->choice.um_Bi_Directional;
+    t_reassembly = decode_t_reassembly(um->dl_UM_RLC.t_Reassembly);
+    if (*um->dl_UM_RLC.sn_FieldLength != *um->ul_UM_RLC.sn_FieldLength) {
+      LOG_E(RLC, "%s:%d:%s: fatal\n", __FILE__, __LINE__, __FUNCTION__);
+      exit(1);
+    }
+    sn_field_length = decode_sn_field_length_um(*um->dl_UM_RLC.sn_FieldLength);
+    break;
+  }
+  default:
+    LOG_E(RLC, "%s:%d:%s: fatal error\n", __FILE__, __LINE__, __FUNCTION__);
+    exit(1);
+  }
+  
+  // Remember that an IAB-MT is an UE
+  nr_rlc_ue_manager_t* nr_rlc_ue_manager = get_rlc_ue_manager();
+    
+  nr_rlc_manager_lock(nr_rlc_ue_manager);
+  nr_rlc_ue_t *ue = nr_rlc_manager_get_ue(nr_rlc_ue_manager, rnti);
+
+  /*AssertFatal(rlc_bhchConfig->bh_LogicalChannelIdentity_r16->choice.bh_LogicalChannelIdentity_r16 != NULL, 
+              "Didn't pass Logical Channel ID during BH-RLC-Channel_config");
+  AssertFatal(rlc_bhchConfig->bh_LogicalChannelIdentity_r16->present == NR_BH_LogicalChannelIdentity_r16_PR_bh_LogicalChannelIdentity_r16,
+              "Given LogicalChannelIdentity isn't supported");
+  */
+  int local_id = rlc_bhchConfig->bh_LogicalChannelIdentity_r16->choice.bh_LogicalChannelIdentity_r16 - 1;
+  BIT_STRING_TO_NR_BHRLCCHANNELID(&rlc_bhchConfig->bh_RLC_ChannelID_r16, ue->lcid2bhch[local_id]);
+
+  if (ue->bhch[bhch_id-1] != NULL) {
+    LOG_E(RLC, "%s:%d:%s: BH Channel %d already exists for IAB-MT with RNTI %04x, do nothing\n", __FILE__, __LINE__, __FUNCTION__, bhch_id, rnti);
+  } else {
+    nr_rlc_entity_t *nr_rlc_um = new_nr_rlc_entity_um(RLC_RX_MAXSIZE,
+                                                      RLC_TX_MAXSIZE,
+                                                      deliver_bap_sdu, ue,
+                                                      t_reassembly,
+                                                      sn_field_length);
+    nr_rlc_ue_add_bhch_rlc_entity(ue, bhch_id, nr_rlc_um);
+
+    LOG_D(RLC, "%s:%d:%s: added BH RLC Channel %d to IAB-MT with RNTI 0x%x\n", __FILE__, __LINE__, __FUNCTION__, bhch_id, rnti);
+  }
+  nr_rlc_manager_unlock(nr_rlc_ue_manager);
+}
+
+static void add_bhch_am(int rnti, int bhch_id, const NR_BH_RLC_ChannelConfig_r16_t *rlc_bhchConfig)
+{
+  struct NR_RLC_Config *r = rlc_bhchConfig->rlc_Config_r16;
+
+  int t_status_prohibit;
+  int t_poll_retransmit;
+  int poll_pdu;
+  int poll_byte;
+  int max_retx_threshold;
+  int t_reassembly;
+  int sn_field_length;
+
+  AssertFatal(bhch_id > 0 && bhch_id <= 32,
+              "Invalid BH RLC Channel ID %d\n", bhch_id);
+
+  switch (r->present) {
+  case NR_RLC_Config_PR_am: {
+    struct NR_RLC_Config__am *am;
+    am = r->choice.am;
+    t_reassembly       = decode_t_reassembly(am->dl_AM_RLC.t_Reassembly);
+    t_status_prohibit  = decode_t_status_prohibit(am->dl_AM_RLC.t_StatusProhibit);
+    t_poll_retransmit  = decode_t_poll_retransmit(am->ul_AM_RLC.t_PollRetransmit);
+    poll_pdu           = decode_poll_pdu(am->ul_AM_RLC.pollPDU);
+    poll_byte          = decode_poll_byte(am->ul_AM_RLC.pollByte);
+    max_retx_threshold = decode_max_retx_threshold(am->ul_AM_RLC.maxRetxThreshold);
+    if (*am->dl_AM_RLC.sn_FieldLength != *am->ul_AM_RLC.sn_FieldLength) {
+      LOG_E(RLC, "%s:%d:%s: fatal\n", __FILE__, __LINE__, __FUNCTION__);
+      exit(1);
+    }
+    sn_field_length    = decode_sn_field_length_am(*am->dl_AM_RLC.sn_FieldLength);
+    break;
+  }
+  default:
+    LOG_E(RLC, "%s:%d:%s: fatal error\n", __FILE__, __LINE__, __FUNCTION__);
+    exit(1);
+  }
+
+  // Remember that an IAB-MT is an UE
+  nr_rlc_ue_manager_t* nr_rlc_ue_manager = get_rlc_ue_manager();
+    
+  nr_rlc_manager_lock(nr_rlc_ue_manager);
+  nr_rlc_ue_t *ue = nr_rlc_manager_get_ue(nr_rlc_ue_manager, rnti);
+
+  /*AssertFatal(rlc_bhchConfig->bh_LogicalChannelIdentity_r16->choice.bh_LogicalChannelIdentity_r16 != NULL, 
+              "Didn't pass Logical Channel ID during BH-RLC-Channel_config");
+  AssertFatal(rlc_bhchConfig->bh_LogicalChannelIdentity_r16->present == NR_rlc_bhchConfig__bh_LogicalChannelIdentity_r16_PR_bh_LogicalChannelIdentity_r16,
+              "Given LogicalChannelIdentity isn't supported");
+  */
+  int local_id = rlc_bhchConfig->bh_LogicalChannelIdentity_r16->choice.bh_LogicalChannelIdentity_r16 - 1;
+  BIT_STRING_TO_NR_BHRLCCHANNELID(&rlc_bhchConfig->bh_RLC_ChannelID_r16, ue->lcid2bhch[local_id]);
+
+  if (ue->bhch[bhch_id-1] != NULL) {
+    LOG_E(RLC, "%s:%d:%s: BH Channel %d already exists for IAB-MT with RNTI %04x, do nothing\n", __FILE__, __LINE__, __FUNCTION__, bhch_id, rnti);
+  } else {
+    nr_rlc_entity_t *nr_rlc_am = new_nr_rlc_entity_am(RLC_RX_MAXSIZE,
+                                                      RLC_TX_MAXSIZE,
+                                                      deliver_bap_sdu, ue,
+                                                      successful_bap_delivery, ue,
+                                                      max_retx_reached, ue,
+                                                      t_poll_retransmit,
+                                                      t_reassembly, t_status_prohibit,
+                                                      poll_pdu, poll_byte, max_retx_threshold,
+                                                      sn_field_length);
+    nr_rlc_ue_add_bhch_rlc_entity(ue, bhch_id, nr_rlc_am);
+
+    LOG_I(RLC, "%s:%d:%s: added BH RLC Channel %d to IAB-MT with RNTI 0x%x\n", __FILE__, __LINE__, __FUNCTION__, bhch_id, rnti);
+  }
+  nr_rlc_manager_unlock(nr_rlc_ue_manager);
+}
+
+void bap_add_bhch(int rnti, int bhch_id, const NR_BH_RLC_ChannelConfig_r16_t *rlc_bhchConfig){
+  switch (rlc_bhchConfig->rlc_Config_r16->present) {
+  case NR_RLC_Config_PR_am:
+    add_bhch_am(rnti, bhch_id, rlc_bhchConfig);
+    break;
+  case NR_RLC_Config_PR_um_Bi_Directional:
+    add_bhch_um(rnti, bhch_id, rlc_bhchConfig);
+    break;
+  default:
+    LOG_E(RLC, "%s:%d:%s: fatal: unhandled BH Channel type\n",
+          __FILE__, __LINE__, __FUNCTION__);
+    exit(1);
+  }
+  LOG_I(RLC, "%s:%s:%d: added BH RLC Channel to IAB-MT with RNTI 0x%x\n", __FILE__, __FUNCTION__, __LINE__, rnti);
+}
+
+void nr_bap_layer_init(bool is_du)
+{
+  /* hack: be sure to initialize only once */
+  static pthread_mutex_t m = PTHREAD_MUTEX_INITIALIZER;
+  static int inited_DU = 0;
+  static int inited_MT = 0;
+
+  if (pthread_mutex_lock(&m) != 0) abort();
+  
+  if (is_du && inited_DU) {
+    // Change LOG to BAP
+    LOG_E(RLC, "%s:%d:%s: fatal, inited_du already 1\n", __FILE__, __LINE__, __FUNCTION__);
+    exit(1);
+  }
+
+  if (!is_du && inited_MT) {
+    // Change LOG to BAP
+    LOG_E(RLC, "%s:%d:%s: fatal, inited_mt already 1\n", __FILE__, __LINE__, __FUNCTION__);
+    exit(1);
+  }
+
+  if (is_du) inited_DU = 1;
+  if (!is_du) inited_MT = 1;
+
+  // nr_rlc_ue_manager = new_nr_rlc_ue_manager(enb_flag);
+
+  if (pthread_mutex_unlock(&m)) abort();
+}
+
+void init_bap_entity(uint16_t bap_addr, bool is_du){
+  bap_entity = new_bap_entity(bap_addr, is_du);
+
+  if (is_du)
+    printf("[BAP]   BAP entity initialized as IAB-DU with BAPAddress = %d\n", bap_entity->bap_address);
+  else
+    printf("[BAP]   BAP entity initialized as IAB-MT with BAPAddress = %d\n", bap_entity->bap_address);
+}

openair2/LAYER2/BAP/bap_oai_api.h

@@ -0,0 +1,5 @@
+#include <stdint.h>
+
+void bap_add_bhch(int rnti, int bhch_id, const NR_BH_RLC_ChannelConfig_r16_t *rlc_bhchConfig);
+void nr_bap_layer_init(bool is_du);
+void init_bap_entity(uint16_t bap_addr, bool is_du);

openair2/LAYER2/BAP/iab_info_management.c

@@ -0,0 +1,4 @@
+
+#include <pthread.h>
+#include "common/utils/hashtable/hashtable.h"
+#include "common/utils/assertions.h"

openair2/LAYER2/BAP/iab_info_management.h

@@ -0,0 +1,65 @@
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netinet/sctp.h>
+
+#ifndef BAP_INFO_H_
+#define BAP_INFO_H_
+
+typedef struct bhch_t{
+  uint16_t bhch_id;
+  nr_rlc_mode_t rlc_mode;
+  long lcid;
+  long priority;
+  uint16_t donor_bap_address;
+  uint16_t node_bap_address[30];
+  uint32_t number_of_nodes;
+}bhch_t;
+
+typedef struct iab_donor_du_t {
+  uint64_t du_id;
+  uint16_t bap_address;
+} iab_donor_du_t;
+
+typedef struct iab_node_du_t {
+  uint64_t du_id;
+} iab_node_du_t;
+
+typedef struct iab_mt_t {
+  uint64_t mt_id; // Don't know if this will useful
+  uint32_t rrc_ue_id;
+} iab_mt_t;
+
+typedef struct iab_node_t {
+  uint16_t bap_address;
+  iab_node_du_t iab_node_du;
+  iab_mt_t iab_mt;
+  uint16_t donor_bap_address;
+} iab_node_t;
+
+typedef struct iab_cu_t {
+  // Max 10 for now
+  iab_donor_du_t iab_donor_du[10];
+  int number_of_iab_donor_dus;
+  // max 30 for now
+  iab_node_t iab_node[30];
+  int number_of_iab_nodes;
+  uint16_t last_given_bap_address;
+  bhch_t *bhch_list;
+  int number_of_bhchs;
+} iab_cu_t;
+
+typedef struct gNB_IAB_INFO_s {
+  union {
+    iab_cu_t iab_cu;
+    iab_donor_du_t iab_donor_du;
+    iab_node_du_t iab_node_du;
+    iab_mt_t iab_mt;
+  };
+} gNB_IAB_INFO;
+
+
+#endif // BAP_INFO_H_
+

openair2/LAYER2/BAP/iab_rrc_info.h

@@ -0,0 +1,19 @@
+#include <stdbool.h>
+#include <stdint.h>
+
+typedef struct bap_routingId_s{
+  uint16_t bap_address;
+  uint16_t bap_pathId;
+} bap_routingId_t;
+
+typedef struct bap_config_s{
+  uint16_t bap_address;
+  bap_routingId_t defaultUL_bap_routingID;
+  uint16_t defaultUL_bhch;
+  
+  enum{
+    perBH_RLC_Channel,
+    perRoutingID,
+    both,
+  }flowControlFeedbackType;
+} bap_config_t;

openair2/LAYER2/MAC/main_ue.c

@@ -112,8 +112,7 @@ int rlcmac_init_global_param_ue(void) {
   return 0;
 }
 
-int
-l2_init_ue(int eMBMS_active, char *uecap_xer, uint8_t cba_group_active,
+int l2_init_ue(int eMBMS_active, char *uecap_xer, uint8_t cba_group_active,
            uint8_t HO_active) {
   LOG_I(MAC, "[MAIN] MAC_INIT_GLOBAL_PARAM IN...\n");
   //    NB_NODE=2;

openair2/LAYER2/NR_MAC_gNB/mac_rrc_dl_handler.c

@@ -25,6 +25,7 @@
 #include "openair2/F1AP/f1ap_ids.h"
 #include "openair2/LAYER2/nr_rlc/nr_rlc_oai_api.h"
 #include "F1AP_CauseRadioNetwork.h"
+#include "openair2/LAYER2/BAP/bap_oai_api.c"
 
 #include "uper_decoder.h"
 #include "uper_encoder.h"
@@ -39,6 +40,13 @@ static long get_lcid_from_drbid(int drb_id)
   return drb_id + 3; /* LCID is DRB + 3 */
 }
 
+/* [IAB] related */
+static long get_lcid_from_bhchid(uint16_t bhch_id)
+{
+  return 33 - bhch_id; // Temporary solution to prevent conflicts
+}
+/* [IAB] end */
+
 static long get_lcid_from_srbid(int srb_id)
 {
   return srb_id;
@@ -189,6 +197,46 @@ static int handle_ue_context_drbs_release(int rnti,
   return drbs_len;
 }
 
+/* [IAB] related function for BH RLC Channel */
+NR_BH_RLC_ChannelConfig_r16_t *get_bhchConfig(const f1ap_bhchannel_to_be_setup_t *bhch){
+  const NR_RLC_Config_PR rlc_conf = bhch->rlc_mode == RLC_MODE_UM ? NR_RLC_Config_PR_um_Bi_Directional : NR_RLC_Config_PR_am;
+  long lcid = get_lcid_from_bhchid(bhch->bHRLCChannelID);
+  long priority = 13; // hardcoded for the moment
+  
+  return get_BH_RLC_ChannelConfig(lcid, bhch->bHRLCChannelID, rlc_conf, priority);
+}
+
+static int handle_ue_context_bhchannels_setup(int rnti,
+                                              int bhchs_len,
+                                              const f1ap_bhchannel_to_be_setup_t *req_bhchs,
+                                              f1ap_bhchannel_to_be_setup_t **resp_bhchs,
+                                              NR_CellGroupConfig_t *cellGroupConfig)
+{
+  DevAssert(req_bhchs != NULL && resp_bhchs != NULL && cellGroupConfig != NULL);
+  
+  /* Note: the actual GTP tunnels are created in the F1AP breanch of
+   * ue_context_*_response() */
+  *resp_bhchs = calloc(bhchs_len, sizeof(**resp_bhchs));
+  AssertFatal(*resp_bhchs != NULL, "out of memory\n");
+  
+  cellGroupConfig->ext2 = calloc(1, sizeof(*cellGroupConfig->ext2));
+  cellGroupConfig->ext2->bh_RLC_ChannelToAddModList_r16 = calloc(bhchs_len, sizeof(NR_BH_RLC_ChannelConfig_r16_t));
+
+  for(int i=0; i<bhchs_len; i++){
+    const f1ap_bhchannel_to_be_setup_t *bhch = &req_bhchs[i];
+    NR_BH_RLC_ChannelConfig_r16_t *rlc_bhchConfig = get_bhchConfig(bhch);
+    bap_add_bhch(rnti, bhch->bHRLCChannelID, rlc_bhchConfig);
+    
+    (*resp_bhchs)[i] = *bhch;
+    
+    int ret = ASN_SEQUENCE_ADD(&cellGroupConfig->ext2->bh_RLC_ChannelToAddModList_r16->list, rlc_bhchConfig);
+    DevAssert(ret == 0);
+  }
+  
+  return bhchs_len;
+}
+/* [IAB] end */
+
 static NR_UE_NR_Capability_t *get_ue_nr_cap(int rnti, uint8_t *buf, uint32_t len)
 {
   if (buf == NULL || len == 0)
@@ -253,7 +301,7 @@ static void set_QoSConfig(const f1ap_ue_context_modif_req_t *req, NR_UE_sched_ct
   AssertFatal(req != NULL, "f1ap_ue_context_modif_req is NULL\n");
   uint8_t drb_count = req->drbs_to_be_setup_length;
   uint8_t srb_count = req->srbs_to_be_setup_length;
-  LOG_I(NR_MAC, "Number of DRBs = %d and SRBs = %d\n", drb_count, srb_count);
+  LOG_I(NR_MAC, "QoSConfig: Number of DRBs = %d and SRBs = %d\n", drb_count, srb_count);
 
   /* DRBs*/
   for (int i = 0; i < drb_count; i++) {
@@ -402,6 +450,7 @@ void ue_context_modification_request(const f1ap_ue_context_modif_req_t *req)
   }
 
   NR_CellGroupConfig_t *new_CellGroup = clone_CellGroupConfig(UE->CellGroup);
+  // new_CellGroup comes with rlc-bearerToAddModList... (is it supposed to though?)
 
   if (req->srbs_to_be_setup_length > 0) {
     resp.srbs_to_be_setup_length = handle_ue_context_srbs_setup(req->gNB_DU_ue_id,
@@ -419,6 +468,16 @@ void ue_context_modification_request(const f1ap_ue_context_modif_req_t *req)
                                                                 new_CellGroup);
   }
 
+  /* [IAB] related configs */
+  if (req->bhchannels_to_be_setup_length > 0){
+    resp.bhchannels_to_be_setup_length = handle_ue_context_bhchannels_setup(req->gNB_DU_ue_id,
+                                                                            req->bhchannels_to_be_setup_length,
+                                                                            req->bhchannels_to_be_setup,
+                                                                            &resp.bhchannels_to_be_setup,
+                                                                            new_CellGroup);
+  }
+  /* [IAB] end */
+
   if (req->drbs_to_be_released_length > 0) {
     resp.drbs_to_be_released_length =
         handle_ue_context_drbs_release(req->gNB_DU_ue_id, req->drbs_to_be_released_length, req->drbs_to_be_released, new_CellGroup);
@@ -442,7 +501,7 @@ void ue_context_modification_request(const f1ap_ue_context_modif_req_t *req)
   }
 
   if (req->srbs_to_be_setup_length > 0 || req->drbs_to_be_setup_length > 0 || req->drbs_to_be_released_length > 0
-      || ue_cap != NULL) {
+      || req->bhchannels_to_be_setup_length > 0 || ue_cap != NULL) {
     resp.du_to_cu_rrc_information = calloc(1, sizeof(du_to_cu_rrc_information_t));
     AssertFatal(resp.du_to_cu_rrc_information != NULL, "out of memory\n");
     resp.du_to_cu_rrc_information->cellGroupConfig = calloc(1, 1024);
@@ -477,6 +536,7 @@ void ue_context_modification_request(const f1ap_ue_context_modif_req_t *req)
   /* free the memory we allocated above */
   free(resp.srbs_to_be_setup);
   free(resp.drbs_to_be_setup);
+  free(resp.bhchannels_to_be_setup);
   if (resp.du_to_cu_rrc_information != NULL) {
     free(resp.du_to_cu_rrc_information->cellGroupConfig);
     free(resp.du_to_cu_rrc_information);

openair2/LAYER2/NR_MAC_gNB/mac_rrc_ul_f1ap.c

@@ -64,6 +64,9 @@ static void f1_setup_request_f1ap(const f1ap_setup_req_t *req)
   f1ap_setup->gNB_DU_id = req->gNB_DU_id;
   f1ap_setup->gNB_DU_name = strdup(req->gNB_DU_name);
   f1ap_setup->num_cells_available = req->num_cells_available;
+  if(req->bap_address != 0){
+    f1ap_setup->bap_address = req->bap_address;
+  }
   for (int n = 0; n < req->num_cells_available; ++n) {
     f1ap_setup->cell[n].info = req->cell[n].info; // copy most fields
     if (req->cell[n].info.tac) {

openair2/LAYER2/NR_MAC_gNB/main.c

@@ -194,6 +194,12 @@ static void mac_rrc_init(gNB_MAC_INST *mac, ngran_node_t node_type)
     case ngran_gNB_DU:
       mac_rrc_ul_f1ap_init(&mac->mac_rrc);
       break;
+    case ngran_gNB_IAB_donor_DU:
+      mac_rrc_ul_f1ap_init(&mac->mac_rrc);
+      break;
+    case ngran_gNB_IAB_node_DU:
+      mac_rrc_ul_f1ap_init(&mac->mac_rrc);
+      break;
     case ngran_gNB:
       mac_rrc_ul_direct_init(&mac->mac_rrc);
       break;

openair2/LAYER2/nr_rlc/nr_rlc_oai_api.c

@@ -54,6 +54,12 @@ static uint64_t nr_rlc_current_time;
 static int      nr_rlc_current_time_last_frame;
 static int      nr_rlc_current_time_last_subframe;
 
+/* [IAB] BAP dependence */
+nr_rlc_ue_manager_t* get_rlc_ue_manager(){
+  return nr_rlc_ue_manager;
+}
+/**/
+
 static void release_rlc_entity_from_lcid(nr_rlc_ue_t *ue, logical_chan_id_t channel_id)
 {
   AssertFatal(channel_id != 0, "LCID = 0 shouldn't be handled here\n");
@@ -468,31 +474,31 @@ rb_found:
 
     if (NODE_IS_DU(type)) {
       if(is_srb) {
-	MessageDef *msg;
-	msg = itti_alloc_new_message(TASK_RLC_ENB, 0, F1AP_UL_RRC_MESSAGE);
-	uint8_t *message_buffer = itti_malloc (TASK_RLC_ENB, TASK_DU_F1, size);
-	memcpy (message_buffer, buf, size);
+        MessageDef *msg;
+        msg = itti_alloc_new_message(TASK_RLC_ENB, 0, F1AP_UL_RRC_MESSAGE);
+        uint8_t *message_buffer = itti_malloc (TASK_RLC_ENB, TASK_DU_F1, size);
+        memcpy (message_buffer, buf, size);
         F1AP_UL_RRC_MESSAGE(msg).gNB_CU_ue_id = ctx.rntiMaybeUEid;
-	F1AP_UL_RRC_MESSAGE(msg).gNB_DU_ue_id = ue->rnti;
-	F1AP_UL_RRC_MESSAGE(msg).srb_id = rb_id;
-	F1AP_UL_RRC_MESSAGE(msg).rrc_container = message_buffer;
-	F1AP_UL_RRC_MESSAGE(msg).rrc_container_length = size;
-	itti_send_msg_to_task(TASK_DU_F1, ENB_MODULE_ID_TO_INSTANCE(0 /*ctxt_pP->module_id*/), msg);
-	return;
+        F1AP_UL_RRC_MESSAGE(msg).gNB_DU_ue_id = ue->rnti;
+        F1AP_UL_RRC_MESSAGE(msg).srb_id = rb_id;
+        F1AP_UL_RRC_MESSAGE(msg).rrc_container = message_buffer;
+        F1AP_UL_RRC_MESSAGE(msg).rrc_container_length = size;
+        itti_send_msg_to_task(TASK_DU_F1, ENB_MODULE_ID_TO_INSTANCE(0 /*ctxt_pP->module_id*/), msg);
+        return;
       } else {
-	MessageDef *msg = itti_alloc_new_message_sized(TASK_RLC_ENB, 0, GTPV1U_TUNNEL_DATA_REQ,
-						       sizeof(gtpv1u_tunnel_data_req_t) + size);
-	gtpv1u_tunnel_data_req_t *req=&GTPV1U_TUNNEL_DATA_REQ(msg);
-	req->buffer=(uint8_t*)(req+1);
-	memcpy(req->buffer,buf,size);
-	req->length=size;
-	req->offset=0;
-	req->ue_id=ue->rnti; // use RNTI here, which GTP will use to look up TEID
-	req->bearer_id=rb_id;
-	LOG_D(RLC, "Received uplink user-plane traffic at RLC-DU to be sent to the CU, size %d \n", size);
-	extern instance_t DUuniqInstance;
-	itti_send_msg_to_task(TASK_GTPV1_U, DUuniqInstance, msg);
-	return;
+        MessageDef *msg = itti_alloc_new_message_sized(TASK_RLC_ENB, 0, GTPV1U_TUNNEL_DATA_REQ,
+                        sizeof(gtpv1u_tunnel_data_req_t) + size);
+        gtpv1u_tunnel_data_req_t *req=&GTPV1U_TUNNEL_DATA_REQ(msg);
+        req->buffer=(uint8_t*)(req+1);
+        memcpy(req->buffer,buf,size);
+        req->length=size;
+        req->offset=0;
+        req->ue_id=ue->rnti; // use RNTI here, which GTP will use to look up TEID
+        req->bearer_id=rb_id;
+        LOG_D(RLC, "Received uplink user-plane traffic at RLC-DU to be sent to the CU, size %d \n", size);
+        extern instance_t DUuniqInstance;
+        itti_send_msg_to_task(TASK_GTPV1_U, DUuniqInstance, msg);
+        return;
       }
     }
   }

openair2/LAYER2/nr_rlc/nr_rlc_oai_api.h

@@ -41,6 +41,8 @@
 struct NR_RLC_Config;
 struct NR_LogicalChannelConfig;
 
+nr_rlc_ue_manager_t* get_rlc_ue_manager();
+
 void nr_rlc_add_srb(int rnti, int srb_id, const NR_RLC_BearerConfig_t *rlc_BearerConfig);
 void nr_rlc_add_drb(int rnti, int drb_id, const NR_RLC_BearerConfig_t *rlc_BearerConfig);
 

openair2/LAYER2/nr_rlc/nr_rlc_ue_manager.c

@@ -206,3 +206,22 @@ void nr_rlc_ue_add_drb_rlc_entity(nr_rlc_ue_t *ue, int drb_id, nr_rlc_entity_t *
 
   ue->drb[drb_id] = entity;
 }
+
+/* [IAB] related config */
+void nr_rlc_ue_add_bhch_rlc_entity(nr_rlc_ue_t *ue, int bhch_id, nr_rlc_entity_t *entity)
+{
+  if (bhch_id < 1 || bhch_id > 32) {
+    LOG_E(RLC, "%s:%d:%s: fatal, bad drb id\n", __FILE__, __LINE__, __FUNCTION__);
+    exit(1);
+  }
+
+  bhch_id--;
+
+  if (ue->bhch[bhch_id] != NULL) {
+    LOG_E(RLC, "%s:%d:%s: fatal, BH Channel already present\n",
+          __FILE__, __LINE__, __FUNCTION__);
+    exit(1);
+  }
+
+  ue->bhch[bhch_id] = entity;
+}

openair2/LAYER2/nr_rlc/nr_rlc_ue_manager.h

@@ -43,7 +43,9 @@ typedef struct nr_rlc_ue_t {
   nr_rlc_entity_t *srb0;
   nr_rlc_entity_t *srb[3];
   nr_rlc_entity_t *drb[MAX_DRBS_PER_UE];
+  nr_rlc_entity_t *bhch[32];
   nr_rlc_rb_t lcid2rb[32];
+  uint16_t lcid2bhch[32];
 } nr_rlc_ue_t;
 
 /***********************************************************************/
@@ -66,5 +68,6 @@ void nr_rlc_manager_remove_ue(nr_rlc_ue_manager_t *m, int rnti);
 
 void nr_rlc_ue_add_srb_rlc_entity(nr_rlc_ue_t *ue, int srb_id, nr_rlc_entity_t *entity);
 void nr_rlc_ue_add_drb_rlc_entity(nr_rlc_ue_t *ue, int drb_id, nr_rlc_entity_t *entity);
+void nr_rlc_ue_add_bhch_rlc_entity(nr_rlc_ue_t *ue, int bhch_id, nr_rlc_entity_t *entity);
 
 #endif /* _NR_RLC_UE_MANAGER_H_ */

openair2/RRC/NR/CMakeLists.txt

@@ -1 +1 @@
-add_subdirectory(MESSAGES)
+add_subdirectory(MESSAGES)

openair2/RRC/NR/MESSAGES/asn1_msg.c

@@ -393,6 +393,55 @@ NR_RLC_BearerConfig_t *get_DRB_RLC_BearerConfig(long lcChannelId, long drbId, NR
   return rlc_BearerConfig;
 }
 
+/* [IAB] BH rlc channel config */
+NR_BH_RLC_ChannelConfig_r16_t *get_BH_RLC_ChannelConfig(long lcChannelId, long bhch_id, NR_RLC_Config_PR rlc_conf, long priority){
+  printf("[ASN1] bhchid = %ld\n", bhch_id);
+  printf("[ASN1] lcChannelId = %ld\n", lcChannelId);
+
+  NR_BH_RLC_ChannelConfig_r16_t *rlc_bhConfig               = calloc(1, sizeof(NR_BH_RLC_ChannelConfig_r16_t));
+  // Using only the old 0 to 32 lcid
+  rlc_bhConfig->bh_LogicalChannelIdentity_r16               = calloc(1, sizeof(NR_BH_LogicalChannelIdentity_r16_t));
+  rlc_bhConfig->bh_LogicalChannelIdentity_r16->present      = NR_BH_LogicalChannelIdentity_r16_PR_bh_LogicalChannelIdentity_r16;
+  rlc_bhConfig->bh_LogicalChannelIdentity_r16->choice.bh_LogicalChannelIdentity_r16 = lcChannelId;
+  
+  NR_BHRLCCHANNELID_TO_BIT_STRING(bhch_id, &rlc_bhConfig->bh_RLC_ChannelID_r16);
+  
+  rlc_bhConfig->reestablishRLC_r16                          = calloc(1, sizeof(e_NR_BH_RLC_ChannelConfig_r16__reestablishRLC_r16));
+  rlc_bhConfig->reestablishRLC_r16                          = NULL;
+
+  NR_RLC_Config_t *rlc_Config = calloc(1, sizeof(NR_RLC_Config_t));
+  // For now, re-use drb config 
+  nr_drb_config(rlc_Config, rlc_conf);
+  rlc_bhConfig->rlc_Config_r16 = rlc_Config;
+
+  NR_LogicalChannelConfig_t *logicalChannelConfig                 = calloc(1, sizeof(NR_LogicalChannelConfig_t));
+  logicalChannelConfig->ul_SpecificParameters                     = calloc(1, sizeof(*logicalChannelConfig->ul_SpecificParameters));
+  logicalChannelConfig->ul_SpecificParameters->priority           = priority;
+  logicalChannelConfig->ul_SpecificParameters->prioritisedBitRate = NR_LogicalChannelConfig__ul_SpecificParameters__prioritisedBitRate_kBps8;
+  logicalChannelConfig->ul_SpecificParameters->bucketSizeDuration = NR_LogicalChannelConfig__ul_SpecificParameters__bucketSizeDuration_ms100;
+
+  long *logicalChannelGroupIAB                                    = CALLOC(1, sizeof(long));
+  /* Set LCG = 1 for BH rlc channels
+   * Since we are using this channel for IAB purposes, we can use the
+   * logicalChannelGroupIAB-Ext-r17, which is inside the range (0 to 255)
+   */
+
+  *logicalChannelGroupIAB                                                       = 1;
+  logicalChannelConfig->ul_SpecificParameters->ext2  = calloc(1, sizeof(*logicalChannelConfig->ul_SpecificParameters->ext2));
+  logicalChannelConfig->ul_SpecificParameters->ext2->logicalChannelGroupIAB_Ext_r17   = CALLOC(1,sizeof(int));
+  logicalChannelConfig->ul_SpecificParameters->ext2->logicalChannelGroupIAB_Ext_r17   = logicalChannelGroupIAB;
+  
+  
+  logicalChannelConfig->ul_SpecificParameters->schedulingRequestID              = CALLOC(1, sizeof(*logicalChannelConfig->ul_SpecificParameters->schedulingRequestID));
+  // Will choose 7 (maximum number) to avoid possible conflicts
+  *logicalChannelConfig->ul_SpecificParameters->schedulingRequestID             = 7;
+  logicalChannelConfig->ul_SpecificParameters->logicalChannelSR_Mask            = 0;
+  logicalChannelConfig->ul_SpecificParameters->logicalChannelSR_DelayTimerApplied = 0;
+  rlc_bhConfig->mac_LogicalChannelConfig_r16                                    = logicalChannelConfig;
+
+  return rlc_bhConfig;
+}
+
 /* returns a default radio bearer config suitable for NSA etc */
 NR_RadioBearerConfig_t *get_default_rbconfig(int eps_bearer_id,
                                              int rb_id,
@@ -926,6 +975,66 @@ uint8_t do_RRCSetupComplete(uint8_t *buffer,
   return((enc_rval.encoded+7)/8);
 }
 
+uint8_t do_RRCSetupComplete_IAB(uint8_t *buffer,
+                            size_t buffer_size,
+                            const uint8_t Transaction_id,
+                            uint8_t sel_plmn_id,
+                            const int dedicatedInfoNASLength,
+                            const char *dedicatedInfoNAS)
+{
+    NR_UL_DCCH_Message_t ul_dcch_msg = {0};
+    ul_dcch_msg.message.present = NR_UL_DCCH_MessageType_PR_c1;
+    ul_dcch_msg.message.choice.c1 = CALLOC(1,sizeof(struct NR_UL_DCCH_MessageType__c1));
+    ul_dcch_msg.message.choice.c1->present = NR_UL_DCCH_MessageType__c1_PR_rrcSetupComplete;
+    ul_dcch_msg.message.choice.c1->choice.rrcSetupComplete = CALLOC(1, sizeof(NR_RRCSetupComplete_t));
+    NR_RRCSetupComplete_t *RrcSetupComplete = ul_dcch_msg.message.choice.c1->choice.rrcSetupComplete;
+    RrcSetupComplete->rrc_TransactionIdentifier = Transaction_id;
+    RrcSetupComplete->criticalExtensions.present = NR_RRCSetupComplete__criticalExtensions_PR_rrcSetupComplete;
+    RrcSetupComplete->criticalExtensions.choice.rrcSetupComplete = CALLOC(1, sizeof(NR_RRCSetupComplete_IEs_t));
+    NR_RRCSetupComplete_IEs_t *ies = RrcSetupComplete->criticalExtensions.choice.rrcSetupComplete;
+    ies->selectedPLMN_Identity = sel_plmn_id;
+    ies->registeredAMF = NULL;
+
+    ies->ng_5G_S_TMSI_Value = CALLOC(1, sizeof(struct NR_RRCSetupComplete_IEs__ng_5G_S_TMSI_Value));
+    ies->ng_5G_S_TMSI_Value->present = NR_RRCSetupComplete_IEs__ng_5G_S_TMSI_Value_PR_ng_5G_S_TMSI;
+    NR_NG_5G_S_TMSI_t *stmsi = &ies->ng_5G_S_TMSI_Value->choice.ng_5G_S_TMSI;
+    stmsi->size = 6;
+    stmsi->buf = calloc(stmsi->size, sizeof(*stmsi->buf));
+    AssertFatal(stmsi->buf != NULL, "out of memory\n");
+    stmsi->buf[0] = 0x12;
+    stmsi->buf[1] = 0x34;
+    stmsi->buf[2] = 0x56;
+    stmsi->buf[3] = 0x78;
+    stmsi->buf[4] = 0x9A;
+    stmsi->buf[5] = 0xBC;
+
+    memset(&ies->dedicatedNAS_Message,0,sizeof(OCTET_STRING_t));
+    OCTET_STRING_fromBuf(&ies->dedicatedNAS_Message, dedicatedInfoNAS, dedicatedInfoNASLength);
+    
+    // ----IAB related params---- 
+    ies->nonCriticalExtension = CALLOC(1, sizeof(NR_RRCSetupComplete_v1610_IEs_t));
+    NR_RRCSetupComplete_v1610_IEs_t *v1610_ies = ies->nonCriticalExtension;
+    v1610_ies->iab_NodeIndication_r16 = CALLOC(1, sizeof(long));
+    *v1610_ies->iab_NodeIndication_r16 = NR_RRCSetupComplete_v1610_IEs__iab_NodeIndication_r16_true;
+    // --------------------------
+
+    if ( LOG_DEBUGFLAG(DEBUG_ASN1) ) {
+        xer_fprint(stdout, &asn_DEF_NR_UL_DCCH_Message, (void *)&ul_dcch_msg);
+    }
+
+    asn_enc_rval_t enc_rval = uper_encode_to_buffer(&asn_DEF_NR_UL_DCCH_Message,
+                                                    NULL,
+                                                    (void *)&ul_dcch_msg,
+                                                    buffer,
+                                                    buffer_size);
+    AssertFatal(enc_rval.encoded > 0,"ASN1 message encoding failed (%s, %lu)!\n",
+                enc_rval.failed_type->name,enc_rval.encoded);
+    LOG_D(NR_RRC,"RRCSetupComplete Encoded %zd bits (%zd bytes)\n",enc_rval.encoded,(enc_rval.encoded+7)/8);
+
+    ASN_STRUCT_FREE_CONTENTS_ONLY(asn_DEF_NR_UL_DCCH_Message, &ul_dcch_msg);
+    return((enc_rval.encoded+7)/8);
+}
+
 uint8_t do_NR_DLInformationTransfer(uint8_t *buffer,
                                     size_t buffer_len,
                                     uint8_t transaction_id,

openair2/RRC/NR/MESSAGES/asn1_msg.h

@@ -70,6 +70,8 @@ NR_RadioBearerConfig_t *get_default_rbconfig(int eps_bearer_id,
                                              e_NR_CipheringAlgorithm ciphering_algorithm,
                                              e_NR_SecurityConfig__keyToUse key_to_use);
 
+NR_BH_RLC_ChannelConfig_r16_t *get_BH_RLC_ChannelConfig(long lcChannelId, long bhch_id, NR_RLC_Config_PR rlc_conf, long priority);
+
 void fill_nr_noS1_bearer_config(NR_RadioBearerConfig_t **rbconfig,
                                 NR_RLC_BearerConfig_t **rlc_rbconfig);
 void free_nr_noS1_bearer_config(NR_RadioBearerConfig_t **rbconfig,
@@ -115,6 +117,13 @@ uint8_t do_RRCSetupComplete(uint8_t *buffer,
                             const int dedicatedInfoNASLength,
                             const char *dedicatedInfoNAS);
 
+uint8_t do_RRCSetupComplete_IAB(uint8_t *buffer,
+                            size_t buffer_size,
+                            const uint8_t Transaction_id,
+                            uint8_t sel_plmn_id,
+                            const int dedicatedInfoNASLength,
+                            const char *dedicatedInfoNAS);
+
 int do_RRCSetupRequest(uint8_t *buffer, size_t buffer_size, uint8_t *rv);
 
 uint8_t do_NR_RRCReconfigurationComplete_for_nsa(uint8_t *buffer, size_t buffer_size, NR_RRC_TransactionIdentifier_t Transaction_id);

openair2/RRC/NR/mac_rrc_dl_f1ap.c

@@ -32,6 +32,9 @@ static void f1_setup_response_f1ap(sctp_assoc_t assoc_id, const f1ap_setup_resp_
   *f1ap_msg = *resp;
   if (resp->gNB_CU_name != NULL)
     f1ap_msg->gNB_CU_name = strdup(resp->gNB_CU_name);
+  if (resp->bap_address != 0){
+    f1ap_msg->bap_address = resp->bap_address;
+  }
   itti_send_msg_to_task(TASK_CU_F1, 0, msg);
 }
 
@@ -123,6 +126,8 @@ static void ue_context_modification_request_f1ap(sctp_assoc_t assoc_id, const f1
     f1ap_msg->rrc_container_length = req->rrc_container_length;
     memcpy(f1ap_msg->rrc_container, req->rrc_container, req->rrc_container_length);
   }
+
+  // Why is it sending to the CU??
   itti_send_msg_to_task(TASK_CU_F1, 0, msg);
 }
 

openair2/RRC/NR/nr_rrc_defs.h

@@ -243,6 +243,7 @@ typedef enum {
   RRC_REESTABLISH_COMPLETE,
   RRC_DEFAULT_RECONF,
   RRC_DEDICATED_RECONF,
+  RRC_IAB_RECONF,
   RRC_PDUSESSION_ESTABLISH,
   RRC_PDUSESSION_MODIFY,
   RRC_PDUSESSION_RELEASE,
@@ -323,6 +324,12 @@ typedef struct gNB_RRC_UE_s {
   /* hack, see rrc_gNB_process_NGAP_PDUSESSION_SETUP_REQ() for more info */
   int max_delays_pdu_session;
 
+  /*[IAB] params*/
+  bool                               is_iab_mt;
+  /* For now, only used to check if already has bap address 
+   * Further IAB information is located at ran_context through gNB_IAB_INFO_s **iab
+  */
+  uint16_t                           bap_address;
 } gNB_RRC_UE_t;
 
 typedef struct rrc_gNB_ue_context_s {
@@ -380,6 +387,8 @@ typedef struct nr_rrc_du_container_t {
   f1ap_setup_req_t *setup_req;
   NR_MIB_t *mib;
   NR_SIB1_t *sib1;
+
+  uint16_t bap_address;
 } nr_rrc_du_container_t;
 
 typedef struct nr_rrc_cuup_container_t {

openair2/RRC/NR/rrc_gNB.c

@@ -57,6 +57,11 @@
 #include "NR_RejectWaitTime.h"
 #include "NR_RRCSetup.h"
 
+//[IAB] includes
+#include "NR_RRCReconfiguration-v1610-IEs.h"
+#include "NR_SetupRelease.h"
+#include "NR_BAP-Config-r16.h"
+
 #include "NR_CellGroupConfig.h"
 #include "NR_MeasResults.h"
 #include "NR_UL-CCCH-Message.h"
@@ -90,6 +95,7 @@
 
 #include "executables/softmodem-common.h"
 #include <openair2/RRC/NR/rrc_gNB_UE_context.h>
+#include <openair2/LAYER2/BAP/iab_info_management.h>
 #include <openair2/X2AP/x2ap_eNB.h>
 #include <openair3/SECU/key_nas_deriver.h>
 #include <openair3/ocp-gtpu/gtp_itf.h>
@@ -99,6 +105,7 @@
 #include "openair2/SDAP/nr_sdap/nr_sdap_entity.h"
 #include "openair2/E1AP/e1ap.h"
 #include "cucp_cuup_if.h"
+#include "openair2/LAYER2/nr_rlc/nr_rlc_entity.h"
 
 #include "BIT_STRING.h"
 #include "assertions.h"
@@ -145,6 +152,7 @@ typedef struct deliver_dl_rrc_message_data_s {
   f1ap_dl_rrc_message_t *dl_rrc;
   sctp_assoc_t assoc_id;
 } deliver_dl_rrc_message_data_t;
+
 static void rrc_deliver_dl_rrc_message(void *deliver_pdu_data, ue_id_t ue_id, int srb_id, char *buf, int size, int sdu_id)
 {
   DevAssert(deliver_pdu_data != NULL);
@@ -307,6 +315,10 @@ static void rrc_gNB_CU_DU_init(gNB_RRC_INST *rrc)
        * soon as this is not the case anymore, we can add the AssertFatal() */
       //AssertFatal(1==0,"nothing to do for DU\n");
       break;
+    case ngran_gNB_IAB_donor_DU:
+      break;
+    case ngran_gNB_IAB_node_DU:
+      break;
     default:
       AssertFatal(0 == 1, "Unknown node type %d\n", rrc->node_type);
       break;
@@ -600,6 +612,7 @@ static void rrc_gNB_generate_defaultRRCReconfiguration(const protocol_ctxt_t *co
                                    measconfig,
                                    dedicatedNAS_MessageList,
                                    ue_p->masterCellGroup);
+                                   
   AssertFatal(size > 0, "cannot encode RRCReconfiguration in %s()\n", __func__);
   free_defaultMeasConfig(measconfig);
   freeSRBlist(SRBs);
@@ -715,6 +728,86 @@ void rrc_gNB_generate_dedicatedRRCReconfiguration(const protocol_ctxt_t *const c
   nr_rrc_transfer_protected_rrc_message(rrc, ue_p, DCCH, buffer, size);
 }
 
+//-----[IAB] Specific RRCReconfig to setup BH RLC Channels and BAP config------
+void rrc_gNB_generate_IAB_RRCReconfiguration(const protocol_ctxt_t *const ctxt_pP, rrc_gNB_ue_context_t *ue_context_pP)
+//-----------------------------------------------------------------------------
+{
+  gNB_RRC_INST *rrc = RC.nrrrc[ctxt_pP->module_id];
+  gNB_IAB_INFO *iab = RC.iab[0];
+
+  uint8_t xid = rrc_gNB_get_next_transaction_identifier(ctxt_pP->module_id);
+  gNB_RRC_UE_t *ue_p = &ue_context_pP->ue_context;
+  ue_p->xids[xid] = RRC_IAB_RECONF;
+  
+  struct NR_RRCReconfiguration_v1610_IEs *reconf_v1610 = CALLOC(1, sizeof(*reconf_v1610));
+  reconf_v1610->bap_Config_r16->present = NR_SetupRelease_BAP_Config_r16_PR_setup;
+  reconf_v1610->bap_Config_r16->choice.setup = CALLOC(1, sizeof(reconf_v1610->bap_Config_r16->choice.setup)); 
+  NR_BAP_Config_r16_t *bap_config = reconf_v1610->bap_Config_r16->choice.setup;
+  NR_BAPADDRESS_TO_BIT_STRING(ue_p->bap_address, bap_config->bap_Address_r16);
+
+  // --- Set cellGroupConfig with bap_address and bhch info ---
+  NR_CellGroupConfig_t *cellGroupConfig = CALLOC(1, sizeof(*cellGroupConfig));
+  cellGroupConfig->cellGroupId = ue_p->masterCellGroup->cellGroupId;
+  NR_BAPADDRESS_TO_BIT_STRING(ue_p->bap_address, cellGroupConfig->ext2->bap_Address_r16);
+  
+  const nr_rrc_du_container_t *donor_du = get_du_for_ue(rrc, ue_p->rrc_ue_id);
+  uint64_t donor_du_id = donor_du->setup_req->gNB_DU_id;
+  uint16_t donor_bap_address = 0;
+  for (int i = 0; i < iab->iab_cu.number_of_iab_donor_dus; i++){
+    if(iab->iab_cu.iab_donor_du[i].du_id == donor_du_id){
+      donor_bap_address = iab->iab_cu.iab_donor_du[i].bap_address;
+      break;
+    }
+  }
+  cellGroupConfig->ext2->bh_RLC_ChannelToAddModList_r16 = CALLOC(1, sizeof(cellGroupConfig->ext2->bh_RLC_ChannelToAddModList_r16));
+  struct NR_CellGroupConfig__ext2__bh_RLC_ChannelToAddModList_r16 *bhch_list = cellGroupConfig->ext2->bh_RLC_ChannelToAddModList_r16;
+  for (int i = 0; i < iab->iab_cu.number_of_bhchs; i++){
+    if (iab->iab_cu.bhch_list[i].donor_bap_address == donor_bap_address){
+      asn1cSequenceAdd(bhch_list->list, NR_BH_RLC_ChannelConfig_r16_t, bhch);
+      int bhch_id = iab->iab_cu.bhch_list[i].bhch_id;
+      long lcid = iab->iab_cu.bhch_list[i].lcid;
+      const NR_RLC_Config_PR rlc_conf = iab->iab_cu.bhch_list[i].rlc_mode == RLC_MODE_UM ? NR_RLC_Config_PR_um_Bi_Directional : NR_RLC_Config_PR_am;
+      long priority = iab->iab_cu.bhch_list[i].priority;
+      bhch = get_BH_RLC_ChannelConfig(lcid, bhch_id, rlc_conf, priority);
+    }
+  }
+
+  // ----------------------------------------------------------
+  //uint8_t buffer[RRC_BUF_SIZE] = {0};
+  /*int size = do_RRCReconfiguration_IAB( ue_p,
+                                    buffer,
+                                    RRC_BUF_SIZE,
+                                    xid,
+                                    cellGroupConfig);
+  */
+  /*
+  int size = do_RRCReconfiguration(ue_p,
+                                   buffer,
+                                   RRC_BUF_SIZE,
+                                   xid,
+                                   SRBs,
+                                   DRBs,
+                                   ue_p->DRB_ReleaseList,
+                                   NULL,
+                                   NULL,
+                                   dedicatedNAS_MessageList,
+                                   cellGroupConfig);
+
+  LOG_I(NR_RRC, "UE %d: Generate RRCReconfiguration (bytes %d, xid %d)\n", ue_p->rrc_ue_id, size, xid);
+  LOG_D(NR_RRC,
+        "[FRAME %05d][RRC_gNB][MOD %u][][--- PDCP_DATA_REQ/%d Bytes (rrcReconfiguration to UE %x MUI %d) --->][PDCP][MOD %u][RB %u]\n",
+        ctxt_pP->frame,
+        ctxt_pP->module_id,
+        size,
+        ue_p->rnti,
+        rrc_gNB_mui,
+        ctxt_pP->module_id,
+        DCCH);
+
+  nr_rrc_transfer_protected_rrc_message(rrc, ue_p, DCCH, buffer, size);
+  */
+}
+
 //-----------------------------------------------------------------------------
 void
 rrc_gNB_modify_dedicatedRRCReconfiguration(
@@ -1539,11 +1632,107 @@ static int handle_rrcSetupComplete(const protocol_ctxt_t *const ctxt_pP,
     }
   }
 
+  // [IAB] related configs
+  if (setup_complete_ies->nonCriticalExtension != NULL){
+    if (*setup_complete_ies->nonCriticalExtension->iab_NodeIndication_r16 == NR_RRCSetupComplete_v1610_IEs__iab_NodeIndication_r16_true){
+      LOG_I(NR_RRC, "IAB Node Indication received and set to true\n");
+      UE->is_iab_mt = true;  
+
+      /* if we did not receive any UE Capabilities, let's do that now. It should
+      * only happen on the first time a reconfiguration arrives. Afterwards, we
+      * should have them. If the UE does not give us anything, we will re-request
+      * the capabilities after each reconfiguration, which is a finite number 
+      if (UE->ue_cap_buffer.len == 0) {
+        rrc_gNB_generate_UECapabilityEnquiry(ctxt_pP, ue_context_p);
+      }
+      */
+      
+    } else{
+      UE->is_iab_mt = false; // not used
+    }
+  }
+  // -------------------
+
   rrc_gNB_process_RRCSetupComplete(ctxt_pP, ue_context_p, setup_complete->criticalExtensions.choice.rrcSetupComplete);
   LOG_I(NR_RRC, PROTOCOL_NR_RRC_CTXT_UE_FMT " UE State = NR_RRC_CONNECTED \n", PROTOCOL_NR_RRC_CTXT_UE_ARGS(ctxt_pP));
   return 0;
 }
 
+static void engage_BH_RLC_Channel_establishment_procedure(rrc_gNB_ue_context_t *ue_context_p){
+  /* Adds new IAB-node (with the IAB-MT). 
+    * Node DU is added later during F1 SETUP Procedure 
+    */
+  
+  gNB_RRC_UE_t *UE = &ue_context_p->ue_context;
+  gNB_IAB_INFO *iab = RC.iab[0];
+  int *number_of_nodes = &iab->iab_cu.number_of_iab_nodes;
+  iab->iab_cu.iab_node[*number_of_nodes].iab_mt.rrc_ue_id = UE->rrc_ue_id;
+  iab->iab_cu.last_given_bap_address += 1;
+  int new_bap_address = iab->iab_cu.last_given_bap_address;
+  iab->iab_cu.iab_node[*number_of_nodes].bap_address = new_bap_address;
+  *number_of_nodes += 1;
+
+  // Call UE Context modification request.
+  gNB_RRC_INST *rrc = RC.nrrrc[0];
+  f1_ue_data_t ue_data = cu_get_f1_ue_data(UE->rrc_ue_id);
+  RETURN_IF_INVALID_ASSOC_ID(ue_data);
+
+  f1ap_bhchannel_to_be_setup_t bhch_buf[1];
+  bhch_buf[0].bHRLCChannelID = 1;
+  bhch_buf[0].rlc_mode = NR_RLC_AM;
+  bhch_buf[0].is_trafficMappingInfo_set = false;
+
+  f1ap_bhchannel_to_be_setup_t *bh_rlc_channels = bhch_buf;           
+
+  f1ap_ue_context_modif_req_t ue_context_modif_req = {
+    .gNB_CU_ue_id = UE->rrc_ue_id,
+    .gNB_DU_ue_id = ue_data.secondary_ue,
+    .plmn.mcc = rrc->configuration.mcc[0],
+    .plmn.mnc = rrc->configuration.mnc[0],
+    .plmn.mnc_digit_length = rrc->configuration.mnc_digit_length[0],
+    .nr_cellid = rrc->nr_cellid,
+    .servCellId = 0, /* TODO: correct value? */     
+    .bhchannels_to_be_setup = bh_rlc_channels,
+    .bhchannels_to_be_setup_length = 1
+  };
+
+  /* Register BH RLC Channel information in the CU
+  */
+  // Get associated donor_du information
+  const nr_rrc_du_container_t *donor_du = get_du_for_ue(rrc, UE->rrc_ue_id);
+  uint64_t donor_du_id = donor_du->setup_req->gNB_DU_id;
+  uint16_t donor_bap_address = 0;
+  for(int i=0; i<iab->iab_cu.number_of_iab_donor_dus; i++){
+    if(iab->iab_cu.iab_donor_du[i].du_id == donor_du_id){
+      donor_bap_address = iab->iab_cu.iab_donor_du[i].bap_address;
+      break;
+    }
+  }
+
+  uint32_t *bhch_number_of_nodes = &iab->iab_cu.bhch_list[iab->iab_cu.number_of_bhchs].number_of_nodes;
+  
+  LOG_I(NR_RRC, "Got to this point: number of bhch = %d\n", bhch_buf[0].bHRLCChannelID);
+  // Insert bhch info in IAB information
+  iab->iab_cu.bhch_list[iab->iab_cu.number_of_bhchs].bhch_id = bhch_buf[0].bHRLCChannelID;
+  LOG_I(NR_RRC, "Got to this point 1\n");
+  iab->iab_cu.bhch_list[iab->iab_cu.number_of_bhchs].rlc_mode = bhch_buf[0].rlc_mode;
+  LOG_I(NR_RRC, "Got to this point 2\n");
+  iab->iab_cu.bhch_list[iab->iab_cu.number_of_bhchs].lcid = 33 - bhch_buf[0].bHRLCChannelID;
+  LOG_I(NR_RRC, "Got to this point 3\n");
+  iab->iab_cu.bhch_list[iab->iab_cu.number_of_bhchs].priority = 13;
+  LOG_I(NR_RRC, "Got to this point 4\n");
+  iab->iab_cu.bhch_list[iab->iab_cu.number_of_bhchs].node_bap_address[*bhch_number_of_nodes] = new_bap_address;
+  LOG_I(NR_RRC, "Got to this point 5\n");
+  iab->iab_cu.bhch_list[iab->iab_cu.number_of_bhchs].donor_bap_address = donor_bap_address;
+  LOG_I(NR_RRC, "Got to this point 6\n");
+  iab->iab_cu.number_of_bhchs += 1;
+  LOG_I(NR_RRC, "Got to this point 7\n");
+  *bhch_number_of_nodes += 1;
+  LOG_I(NR_RRC, "Got to this point 8\n");
+
+  rrc->mac_rrc.ue_context_modification_request(ue_data.du_assoc_id, &ue_context_modif_req);    
+}
+
 static void handle_rrcReconfigurationComplete(const protocol_ctxt_t *const ctxt_pP,
                                               rrc_gNB_ue_context_t *ue_context_p,
                                               const NR_RRCReconfigurationComplete_t *reconfig_complete)
@@ -1572,6 +1761,9 @@ static void handle_rrcReconfigurationComplete(const protocol_ctxt_t *const ctxt_
       break;
     case RRC_DEFAULT_RECONF:
       rrc_gNB_send_NGAP_INITIAL_CONTEXT_SETUP_RESP(ctxt_pP, ue_context_p);
+      if(UE->is_iab_mt){
+        engage_BH_RLC_Channel_establishment_procedure(ue_context_p);
+      }
       break;
     case RRC_REESTABLISH_COMPLETE:
     case RRC_DEDICATED_RECONF:
@@ -1581,6 +1773,9 @@ static void handle_rrcReconfigurationComplete(const protocol_ctxt_t *const ctxt_
       LOG_E(RRC, "UE %d: Received RRC Reconfiguration Complete with xid %d while no transaction is ongoing\n", UE->rrc_ue_id, xid);
       successful_reconfig = false;
       break;
+    case RRC_IAB_RECONF:
+      /* do nothing */
+      break;
     default:
       LOG_E(RRC, "UE %d: Received unexpected transaction type %d for xid %d\n", UE->rrc_ue_id, UE->xids[xid], xid);
       successful_reconfig = false;
@@ -1606,7 +1801,10 @@ static void handle_rrcReconfigurationComplete(const protocol_ctxt_t *const ctxt_
     .servCellId = 0, /* TODO: correct value? */
     .ReconfigComplOutcome = successful_reconfig ? RRCreconf_success : RRCreconf_failure,
   };
-  rrc->mac_rrc.ue_context_modification_request(ue_data.du_assoc_id, &ue_context_modif_req);
+  // [IAB] IAB-MT troubleshoot (it shouldn't send modification request again)
+  if(UE->is_iab_mt == false){
+    rrc->mac_rrc.ue_context_modification_request(ue_data.du_assoc_id, &ue_context_modif_req);
+  }
 
   /* if we did not receive any UE Capabilities, let's do that now. It should
    * only happen on the first time a reconfiguration arrives. Afterwards, we
@@ -2000,7 +2198,23 @@ static void rrc_CU_process_ue_context_modification_response(MessageDef *msg_p, i
     }
     UE->masterCellGroup = cellGroupConfig;
 
-    rrc_gNB_generate_dedicatedRRCReconfiguration(&ctxt, ue_context_p);
+    /* [IAB] */
+    if(UE->is_iab_mt){
+      // If BAP Address isn't set yet (Configuring new IAB-MT)
+      if(UE->bap_address == 0){
+        gNB_IAB_INFO *iab = RC.iab[0];
+        for (int i=0; i<iab->iab_cu.number_of_iab_nodes; i++){
+          if(iab->iab_cu.iab_node[i].iab_mt.rrc_ue_id == UE->rrc_ue_id){
+            UE->bap_address = iab->iab_cu.iab_node[i].bap_address;
+          }
+        }
+        rrc_gNB_generate_IAB_RRCReconfiguration(&ctxt, ue_context_p);
+      } else {
+        // Future use (modifying an IAB-MT that is already configured)
+      }
+    }else{
+      rrc_gNB_generate_dedicatedRRCReconfiguration(&ctxt, ue_context_p);
+    }
   }
 }
 

openair2/RRC/NR/rrc_gNB_du.c

@@ -19,9 +19,11 @@
  *      contact@openairinterface.org
  */
 
+#include <string.h>
 #include "rrc_gNB_du.h"
 #include "common/ran_context.h"
 #include "nr_rrc_defs.h"
+#include "openair2/LAYER2/BAP/iab_info_management.h"
 #include "rrc_gNB_UE_context.h"
 #include "openair2/F1AP/f1ap_common.h"
 #include "openair2/F1AP/f1ap_ids.h"
@@ -54,12 +56,15 @@ void rrc_gNB_process_f1_setup_req(f1ap_setup_req_t *req, sctp_assoc_t assoc_id)
   gNB_RRC_INST *rrc = RC.nrrrc[0];
   DevAssert(rrc);
 
+  gNB_IAB_INFO *iab = RC.iab[0];
+
   LOG_I(NR_RRC, "Received F1 Setup Request from gNB_DU %lu (%s) on assoc_id %d\n", req->gNB_DU_id, req->gNB_DU_name, assoc_id);
 
   // check:
   // - it is one cell
   // - PLMN and Cell ID matches
   // - no previous DU with the same ID
+  // - no previous DU with the same BAP Address
   // else reject
   if (req->num_cells_available != 1) {
     LOG_E(NR_RRC, "can only handle on DU cell, but gNB_DU %ld has %d\n", req->gNB_DU_id, req->num_cells_available);
@@ -91,6 +96,16 @@ void rrc_gNB_process_f1_setup_req(f1ap_setup_req_t *req, sctp_assoc_t assoc_id)
       rrc->mac_rrc.f1_setup_failure(assoc_id, &fail);
       return;
     }
+    if (it->setup_req->bap_address == req->bap_address && req->bap_address != 0){
+      LOG_E(NR_RRC,
+            "BAPAddress: existing DU %s on assoc_id %d already has BAPAddress %d, rejecting requesting gNB-DU\n",
+            it->setup_req->gNB_DU_name,
+            it->assoc_id,
+            it->setup_req->bap_address);
+      f1ap_setup_failure_t fail = {.cause = F1AP_CauseMisc_unspecified};
+      rrc->mac_rrc.f1_setup_failure(assoc_id, &fail);
+      return;
+    }
     // note: we assume that each DU contains only one cell; otherwise, we would
     // need to check every cell in the requesting DU to any existing cell.
     const f1ap_served_cell_info_t *exist_info = &it->setup_req->cell[0].info;
@@ -160,8 +175,6 @@ void rrc_gNB_process_f1_setup_req(f1ap_setup_req_t *req, sctp_assoc_t assoc_id)
     ASN_STRUCT_FREE(asn_DEF_NR_BCCH_BCH_MessageType, mib);
     du->sib1 = sib1;
   }
-  RB_INSERT(rrc_du_tree, &rrc->dus, du);
-  rrc->num_dus++;
 
   served_cells_to_activate_t cell = {
       .plmn = cell_info->plmn,
@@ -175,8 +188,37 @@ void rrc_gNB_process_f1_setup_req(f1ap_setup_req_t *req, sctp_assoc_t assoc_id)
                             .cells_to_activate[0] = cell};
   int num = read_version(TO_STRING(NR_RRC_VERSION), &resp.rrc_ver[0], &resp.rrc_ver[1], &resp.rrc_ver[2]);
   AssertFatal(num == 3, "could not read RRC version string %s\n", TO_STRING(NR_RRC_VERSION));
-  if (rrc->node_name != NULL)
+  if (rrc->node_name != NULL){
     resp.gNB_CU_name = strdup(rrc->node_name);
+  }
+
+  /* [IAB]
+  */ 
+  if(strstr(req->gNB_DU_name, "Donor") != NULL){
+    iab->iab_cu.last_given_bap_address += 1;
+    int new_bap_address = iab->iab_cu.last_given_bap_address;
+    printf("Giving BAP Address = %d\n", new_bap_address);
+    resp.bap_address = new_bap_address;
+    iab_donor_du_t *iab_donor_du = &iab->iab_cu.iab_donor_du[iab->iab_cu.number_of_iab_donor_dus];
+    iab_donor_du->du_id = req->gNB_DU_id;
+    iab_donor_du->bap_address = new_bap_address;
+    iab->iab_cu.number_of_iab_donor_dus += 1;
+    // Adding BAP Address here to make search easier
+    du->bap_address = new_bap_address;
+  } else if (strstr(req->gNB_DU_name, "Node") != NULL) {
+    printf("Receiving BAP Address = %d\n", req->bap_address);
+    du->bap_address = req->bap_address;
+    for (int i = 0; i < iab->iab_cu.number_of_iab_nodes; i++){
+      if (iab->iab_cu.iab_node[i].bap_address == req->bap_address){
+        iab->iab_cu.iab_node[i].iab_node_du.du_id = req->gNB_DU_id;
+        break;
+      } 
+    }
+  }
+
+  RB_INSERT(rrc_du_tree, &rrc->dus, du);
+  rrc->num_dus++;
+  
   rrc->mac_rrc.f1_setup_response(assoc_id, &resp);
 
   /*

openair2/RRC/NR/rrc_gNB_du.h

@@ -30,6 +30,7 @@
 struct f1ap_setup_req_s;
 struct f1ap_lost_connection_t;
 struct gNB_RRC_INST_s;
+struct gNB_IAB_INFO_s;
 struct nr_rrc_du_container_t;
 
 void rrc_gNB_process_f1_setup_req(struct f1ap_setup_req_s *req, sctp_assoc_t assoc_id);

openair2/RRC/NR_UE/rrc_UE.c

@@ -834,7 +834,8 @@ static void rrc_ue_generate_RRCSetupComplete(const NR_UE_RRC_INST_t *rrc, const
     nas_msg_length = sizeof(nr_nas_attach_req_imsi_dummy_NSA_case);
   }
 
-  size = do_RRCSetupComplete(buffer, sizeof(buffer), Transaction_id, rrc->selected_plmn_identity, nas_msg_length, nas_msg);
+  //size = do_RRCSetupComplete(buffer, sizeof(buffer), Transaction_id, rrc->selected_plmn_identity, nas_msg_length, nas_msg);
+  size = do_RRCSetupComplete_IAB(buffer, sizeof(buffer), Transaction_id, rrc->selected_plmn_identity, nas_msg_length, nas_msg);
   LOG_I(NR_RRC, "[UE %ld][RAPROC] Logical Channel UL-DCCH (SRB1), Generating RRCSetupComplete (bytes%d)\n", rrc->ue_id, size);
   int srb_id = 1; // RRC setup complete on SRB1
   LOG_D(NR_RRC, "[RRC_UE %ld] PDCP_DATA_REQ/%d Bytes RRCSetupComplete ---> %d\n", rrc->ue_id, size, srb_id);

openair3/NGAP/ngap_gNB_defs.h

@@ -248,6 +248,9 @@ typedef struct ngap_gNB_instance_s {
   /* Tracking area code */
   uint32_t tac;
 
+  /* [IAB] donor-DU bap address */
+  uint16_t bap_address;
+
   /* gNB NGAP IP address */
   net_ip_address_t gNB_ng_ip;
   

openair3/UTILS/conversions.h

@@ -455,6 +455,105 @@ do {                                                    \
     (bITsTRING)->bits_unused = 4;                       \
 } while(0)
 
+// [IAB] Related macros
+
+/* TS 38.331 BH-RLC-ChannelID
+ * uint16_t to BIT STRING (SIZE(16))
+ */
+#define NR_BHRLCCHANNELID_TO_BIT_STRING(mACRO, bITsTRING)      \
+do {                                                    \
+    (bITsTRING)->buf = calloc(2, sizeof(uint8_t));      \
+    (bITsTRING)->buf[0] = ((mACRO) >> 8) & 0xff;        \
+    (bITsTRING)->buf[1] = (mACRO) & 0xff;               \
+    (bITsTRING)->size = 2;                              \
+    (bITsTRING)->bits_unused = 0;                       \
+} while(0)
+
+/* MappingInformationIndex
+ * uint32_t to BIT STRING (SIZE(26))
+ */
+#define NR_MAPPINGINFORMATIONINDEX_TO_BIT_STRING(mACRO, bITsTRING)      \
+do {                                                    \
+    (bITsTRING)->buf = calloc(4, sizeof(uint8_t));      \
+    (bITsTRING)->buf[0] = ((mACRO) >> 18) & 0xff;       \
+    (bITsTRING)->buf[1] = ((mACRO) >> 10) & 0xff;       \
+    (bITsTRING)->buf[2] = ((mACRO) >> 2) & 0xff;        \
+    (bITsTRING)->buf[3] = ((mACRO) & 0x03) << 6;        \
+    (bITsTRING)->size = 4;                              \
+    (bITsTRING)->bits_unused = 6;                       \
+} while(0)
+
+
+#define IABTNL_ADRESS_IPv4_TO_BIT_STRING(mACRO, bITsTRING)  \
+do {                                                    \
+    (bITsTRING)->buf = calloc(4, sizeof(uint8_t));      \
+    (bITsTRING)->buf[3] = (mACRO) >> 24 & 0xFF;         \
+    (bITsTRING)->buf[2] = (mACRO) >> 16 & 0xFF;         \
+    (bITsTRING)->buf[1] = (mACRO) >> 8 & 0xFF;          \
+    (bITsTRING)->buf[0] = (mACRO) &  0xFF;              \
+    (bITsTRING)->size = 4;                              \
+    (bITsTRING)->bits_unused = 0;                       \
+} while(0)
+
+/* DSCP
+ * uint8_t to BIT STRING (SIZE(6))
+ */
+#define DSCP_TO_BIT_STRING(mACRO, bITsTRING)      \
+do {                                                   \
+    (bITsTRING)->buf = calloc(1, sizeof(uint8_t));     \
+    (bITsTRING)->buf[0] = ((mACRO) & 0x3f) << 2;              \
+    (bITsTRING)->size = 1;                             \
+    (bITsTRING)->bits_unused = 2;                      \
+} while(0)
+
+/* BAPAddress
+ * uint16_t to BIT STRING (SIZE(10))
+ */
+#define NR_BAPADDRESS_TO_BIT_STRING(mACRO, bITsTRING)      \
+do {                                                    \
+    (bITsTRING)->buf = calloc(2, sizeof(uint8_t));      \
+    (bITsTRING)->buf[0] = ((mACRO) >> 2) & 0xff;        \
+    (bITsTRING)->buf[1] = ((mACRO) & 0xff) << 6;               \
+    (bITsTRING)->size = 2;                              \
+    (bITsTRING)->bits_unused = 6;                       \
+} while(0)
+
+/* BAPPathID
+ * uint16_t to BIT STRING (SIZE(10))
+ */
+#define NR_BAPPATHID_TO_BIT_STRING(mACRO, bITsTRING)      \
+do {                                                    \
+    (bITsTRING)->buf = calloc(2, sizeof(uint8_t));      \
+    (bITsTRING)->buf[0] = ((mACRO) >> 2) & 0xff;        \
+    (bITsTRING)->buf[1] = ((mACRO) & 0xff) << 6;               \
+    (bITsTRING)->size = 2;                              \
+    (bITsTRING)->bits_unused = 6;                       \
+} while(0)
+
+/*
+ * BIT STRING (SIZE(16)) to uint16_t
+ */
+#define BIT_STRING_TO_NR_BHRLCCHANNELID(bITsTRING, mACRO) \
+do {                                                      \
+    DevCheck((bITsTRING)->size == 2, (bITsTRING)->size, 2, 0); \
+    DevCheck((bITsTRING)->bits_unused == 0, (bITsTRING)->bits_unused, 0, 0); \
+    mACRO = (((uint16_t) (bITsTRING)->buf[0]) << 8) +     \
+            ((uint16_t) (bITsTRING)->buf[1]);              \
+} while (0)
+
+/*
+ * BIT STRING (SIZE(10)) to uint16_t
+ */
+#define BIT_STRING_TO_NR_BAPADDRESS(bITsTRING, mACRO) \
+do{                                                \
+    DevCheck((bITsTRING)->size == 2, (bITsTRING)->size, 2, 0); \
+    DevCheck((bITsTRING)->bits_unused == 6, (bITsTRING)->bits_unused, 6, 0); \
+    mACRO = (((uint16_t) (bITsTRING)->buf[0]) << 2) +     \
+            ((uint16_t) (bITsTRING)->buf[1] >> 6);         \
+} while(0)
+
+// [IAB] End related macros
+
 /*
 #define INT16_TO_3_BYTE_BUFFER(x, buf) \
 do {                            \