Introduce additional option to bind on separate IFs for F1-C/U in DU

After the last commit, it is not possible to bind on separate interfaces
for F1-C and F1-U. In other words, it is for instance not possible to
have the F1-C on one subnet on one physical interface, and F1-U on
another subnet on another physical interface. This commit introduces a
second option MACRLCs.[0].local_n_address_f1u to allow to bind F1-U on
an alternative address; if it is not specified, the interface of F1-C is
reused.

The above only works for the DU; no corresponding option exists for the
CU. For the CU, use separate CU-CP and CU-UP.

Use it in the CI.

ci-scripts/yaml_files/5g_rfsimulator_e1/docker-compose.yaml

@@ -187,8 +187,9 @@ services:
         container_name: rfsim5g-oai-du
         environment:
             USE_ADDITIONAL_OPTIONS: --sa --rfsim --log_config.global_log_options level,nocolor,time
-                                    --MACRLCs.[0].local_n_address 192.168.73.3
+                                    --MACRLCs.[0].local_n_address 192.168.72.3
                                     --MACRLCs.[0].remote_n_address 192.168.72.2
+                                    --MACRLCs.[0].local_n_address_f1u 192.168.73.3
             ASAN_OPTIONS: detect_leaks=0
         depends_on:
             - oai-cucp
@@ -217,8 +218,9 @@ services:
                                     --gNBs.[0].gNB_DU_ID 0xe01
                                     --gNBs.[0].nr_cellid 87654321
                                     --gNBs.[0].servingCellConfigCommon.[0].physCellId 1
-                                    --MACRLCs.[0].local_n_address 192.168.74.3
                                     --MACRLCs.[0].remote_n_address 192.168.72.2
+                                    --MACRLCs.[0].local_n_address 192.168.72.4
+                                    --MACRLCs.[0].local_n_address_f1u 192.168.74.3
             ASAN_OPTIONS: detect_leaks=0
         depends_on:
             - oai-cucp
@@ -247,8 +249,9 @@ services:
                                     --gNBs.[0].gNB_DU_ID 0xe02
                                     --gNBs.[0].nr_cellid 11111111
                                     --gNBs.[0].servingCellConfigCommon.[0].physCellId 2
-                                    --MACRLCs.[0].local_n_address 192.168.76.3
                                     --MACRLCs.[0].remote_n_address 192.168.72.2
+                                    --MACRLCs.[0].local_n_address 192.168.72.5
+                                    --MACRLCs.[0].local_n_address_f1u 192.168.76.3
             ASAN_OPTIONS: detect_leaks=0
         depends_on:
             - oai-cucp

doc/F1-design.md

@@ -124,11 +124,12 @@ gNB, are, in order:
    (`tr_s_preference`), it is a CU.
 3. It is a (monolithic) gNB.
 
-## Local network deployment of F1
+## F1 IP configuration for Local network deployment of F1
 
-For a local deployment, you should update the following fields.
-We assume that the CU will bind on `192.168.70.129` towards the core,
-`127.0.0.3` towards the DU, and the DU `127.0.0.4` towards the CU.
+The following paragraphs explain the IP configuration for F1 in the OAI config
+files on the example of a a local deployment.  We assume that the CU will bind
+on `192.168.70.129` towards the core, `127.0.0.3` towards the DU, and the DU
+`127.0.0.4` towards the CU.
 
 In the CU file:
 - Update the `gNBs.[0].amf_ip_address` and `gNBs.[0].NETWORK_INTERFACES`
@@ -138,8 +139,8 @@ In the CU file:
   - `gNBs.[0].NETWORK_INTERFACES.GNB_IPV4_ADDRESS_FOR_NG_AMF 192.168.70.129`
   - `gNBs.[0].NETWORK_INTERFACES.GNB_IPV4_ADDRESS_FOR_NGU 192.168.70.132`
 - Set `gNBs.[0].tr_s_preference` (transport south-bound) to `f1`
-- Update the `gNBs.[0].local_s_address` (CU-local south address) for the F1-C
-  south-bound interface: `127.0.0.3`
+- Update the `gNBs.[0].local_s_address` (CU-local south address) for the
+  F1-C/SCTP and F1-U/GTP/UDP south-bound interfaces: `127.0.0.3`
 - Note: the `gNBs.[0].remote_s_address` (CU-remote/DU south address) is
   ignored, but we recommend to put `0.0.0.0` ("any")
 - Ports should match the ones in the DU config, but for simplicity and
@@ -152,14 +153,23 @@ In the CU file:
 In the DU file:
 - Set `MACRLCs.[0].tr_n_preference` to `f1`
 - Update `MACRLCs.[0].local_n_address` (local north-bound address of the DU) to
-  `127.0.0.4`. This IP address is used to bind the GTP socket (F1-U user plane
-  traffic).
+  `127.0.0.4`. This IP address is used to bind the F1-C/SCTP and F1-U/GTP/UDP
+  socket.
+- If you need to bind to different addresses for F1-C and F1-U, there is a
+  second option `MACRLCs.[0].local_n_address_f1u` which is used to bind
+  F1-U/GTP/UDP instead; F1-C/SCTP will still bind to the address in
+  `MACRLCs.[0].local_n_address`.
 - Update `MACRLCs.[].remote_n_address` (remote north-bound address of the CU)
   to `127.0.0.3`. This IP address is used as the CU destination IP address for
   F1AP communication.
 
 Note: all `local_*_if_name` parameters are ignored.
 
+Note 2: at the DU, you can bind to different interfaces for F1-C and F1-U with
+the options `MACRLCs.[0].local_n_address` and
+`MACRLCs.[0].local_n_address_f1u`, respectively. Note that this is not foreseen
+for the CU; in the case of the CU, please use separate CU-UP and CU-CP.
+
 ## Configuration of multiple DUs
 
 Upon F1 Setup Request of a new DU, the CU cross-checks that

openair2/COMMON/f1ap_messages_types.h

@@ -78,7 +78,8 @@ typedef net_ip_address_t f1ap_net_ip_address_t;
 
 typedef struct f1ap_net_config_t {
   f1ap_net_ip_address_t CU_f1_ip_address;
-  f1ap_net_ip_address_t DU_f1_ip_address;
+  f1ap_net_ip_address_t DU_f1c_ip_address;
+  char *DU_f1u_ip_address;
   uint16_t CUport;
   uint16_t DUport;
 } f1ap_net_config_t;

openair2/F1AP/f1ap_du_task.c

@@ -43,7 +43,7 @@ instance_t DUuniqInstance=0;
 static instance_t du_create_gtpu_instance_to_cu(const f1ap_net_config_t *nc)
 {
   openAddr_t tmp = {0};
-  strncpy(tmp.originHost, nc->DU_f1_ip_address.ipv4_address, sizeof(tmp.originHost) - 1);
+  strncpy(tmp.originHost, nc->DU_f1u_ip_address, sizeof(tmp.originHost) - 1);
   strncpy(tmp.destinationHost, nc->CU_f1_ip_address.ipv4_address, sizeof(tmp.destinationHost) - 1);
   sprintf(tmp.originService, "%d", nc->DUport);
   sprintf(tmp.destinationService, "%d", nc->CUport);
@@ -65,7 +65,7 @@ void du_task_send_sctp_association_req(instance_t instance, f1ap_net_config_t *n
   // remote
   memcpy(&sctp_new_association_req_p->remote_address, &nc->CU_f1_ip_address, sizeof(nc->CU_f1_ip_address));
   // local
-  memcpy(&sctp_new_association_req_p->local_address, &nc->DU_f1_ip_address, sizeof(nc->DU_f1_ip_address));
+  memcpy(&sctp_new_association_req_p->local_address, &nc->DU_f1c_ip_address, sizeof(nc->DU_f1c_ip_address));
   // du_f1ap_register_to_sctp
   itti_send_msg_to_task(TASK_SCTP, instance, message_p);
 }

openair2/F1AP/f1ap_du_ue_context_management.c

@@ -1189,7 +1189,7 @@ int DU_send_UE_CONTEXT_MODIFICATION_RESPONSE(sctp_assoc_t assoc_id, f1ap_ue_cont
         asn1cCalloc(dLUPTNLInformation_ToBeSetup_Item->dLUPTNLInformation.choice.gTPTunnel, gTPTunnel);
         /* transportLayerAddress */
         struct sockaddr_in addr= {0};
-        inet_pton(AF_INET, getCxt(0)->net_config.DU_f1_ip_address.ipv4_address, &addr.sin_addr.s_addr);
+        inet_pton(AF_INET, getCxt(0)->net_config.DU_f1u_ip_address, &addr.sin_addr.s_addr);
         TRANSPORT_LAYER_ADDRESS_IPv4_TO_BIT_STRING(addr.sin_addr.s_addr, &gTPTunnel->transportLayerAddress);
         /* gTP_TEID */
         INT32_TO_OCTET_STRING(resp->drbs_to_be_modified[i].up_dl_tnl[j].teid, &gTPTunnel->gTP_TEID);

openair2/GNB_APP/MACRLC_nr_paramdef.h

@@ -41,6 +41,7 @@
 #define CONFIG_STRING_MACRLC_TRANSPORT_N_PREFERENCE        "tr_n_preference"
 #define CONFIG_STRING_MACRLC_LOCAL_N_IF_NAME               "local_n_if_name"
 #define CONFIG_STRING_MACRLC_LOCAL_N_ADDRESS               "local_n_address"
+#define CONFIG_STRING_MACRLC_LOCAL_N_ADDRESS_F1U           "local_n_address_f1u"
 #define CONFIG_STRING_MACRLC_REMOTE_N_ADDRESS              "remote_n_address"
 #define CONFIG_STRING_MACRLC_LOCAL_N_PORTC                 "local_n_portc"
 #define CONFIG_STRING_MACRLC_REMOTE_N_PORTC                "remote_n_portc"
@@ -125,6 +126,7 @@
   {CONFIG_STRING_MACRLC_MIN_GRANT_PRB,               HLP_MACRLC_MIN_GRANT_PRB, 0, .u8ptr=NULL,  .defintval=5,               TYPE_UINT8,   0}, \
   {CONFIG_STRING_MACRLC_MIN_GRANT_MCS,               HLP_MACRLC_MIN_GRANT_MCS, 0, .u8ptr=NULL,  .defintval=9,               TYPE_UINT8,   0}, \
   {CONFIG_STRING_MACRLC_IDENTITY_PM,                 HLP_MACRLC_IDENTITY_PM,   PARAMFLAG_BOOL, .u8ptr=NULL, .defintval=0,   TYPE_UINT8,   0}, \
+  {CONFIG_STRING_MACRLC_LOCAL_N_ADDRESS_F1U,         NULL,                     0, .strptr=NULL, .defstrval=NULL,            TYPE_STRING,  0}, \
 }
 // clang-format off
 
@@ -162,6 +164,7 @@
 #define MACRLC_MIN_GRANT_PRB_IDX                               31
 #define MACRLC_MIN_GRANT_MCS_IDX                               32
 #define MACRLC_IDENTITY_PM_IDX                                 33
+#define MACRLC_LOCAL_N_ADDRESS_F1U_IDX                         34
 
 #define MACRLCPARAMS_CHECK { \
   { .s5 = { NULL } }, \
@@ -198,6 +201,7 @@
   { .s5 = { NULL } }, \
   { .s5 = { NULL } }, \
   { .s2 = { NULL } }, \
+  { .s5 = { NULL } }, \
 }
 
 /*---------------------------------------------------------------------------------------------------------------------------------------------------------*/

openair2/GNB_APP/gnb_config.c

@@ -1279,7 +1279,10 @@ void RCconfig_nr_macrlc(configmodule_interface_t *cfg)
                  || strcmp(*(MacRLC_ParamList.paramarray[j][MACRLC_TRANSPORT_N_PREFERENCE_IDX].strptr), "cudu") == 0) {
         printf("Configuring F1 interfaces for MACRLC\n");
         RC.nrmac[j]->eth_params_n.local_if_name = strdup(*(MacRLC_ParamList.paramarray[j][MACRLC_LOCAL_N_IF_NAME_IDX].strptr));
-        RC.nrmac[j]->eth_params_n.my_addr = strdup(*(MacRLC_ParamList.paramarray[j][MACRLC_LOCAL_N_ADDRESS_IDX].strptr));
+        char **f1caddr = MacRLC_ParamList.paramarray[j][MACRLC_LOCAL_N_ADDRESS_IDX].strptr;
+        RC.nrmac[j]->eth_params_n.my_addr = strdup(*f1caddr);
+        char **f1uaddr = MacRLC_ParamList.paramarray[j][MACRLC_LOCAL_N_ADDRESS_F1U_IDX].strptr;
+        RC.nrmac[j]->f1u_addr = f1uaddr != NULL ? strdup(*f1uaddr) : strdup(*f1caddr);
         RC.nrmac[j]->eth_params_n.remote_addr = strdup(*(MacRLC_ParamList.paramarray[j][MACRLC_REMOTE_N_ADDRESS_IDX].strptr));
         RC.nrmac[j]->eth_params_n.my_portc = *(MacRLC_ParamList.paramarray[j][MACRLC_LOCAL_N_PORTC_IDX].iptr);
         RC.nrmac[j]->eth_params_n.remote_portc = *(MacRLC_ParamList.paramarray[j][MACRLC_REMOTE_N_PORTC_IDX].iptr);

openair2/LAYER2/NR_MAC_gNB/mac_rrc_ul_f1ap.c

@@ -29,7 +29,7 @@
 
 #include "mac_rrc_ul.h"
 
-static f1ap_net_config_t read_DU_IP_config(const eth_params_t* f1_params)
+static f1ap_net_config_t read_DU_IP_config(const eth_params_t* f1_params, const char *f1u_ip_addr)
 {
   f1ap_net_config_t nc = {0};
 
@@ -37,19 +37,17 @@ static f1ap_net_config_t read_DU_IP_config(const eth_params_t* f1_params)
   nc.CU_f1_ip_address.ipv4 = 1;
   strcpy(nc.CU_f1_ip_address.ipv4_address, f1_params->remote_addr);
   nc.CUport = f1_params->remote_portd;
-  LOG_I(GNB_APP,
-        "FIAP: CU_ip4_address in DU %p, strlen %d\n",
-        nc.CU_f1_ip_address.ipv4_address,
-        (int)strlen(f1_params->remote_addr));
 
-  nc.DU_f1_ip_address.ipv6 = 0;
-  nc.DU_f1_ip_address.ipv4 = 1;
-  strcpy(nc.DU_f1_ip_address.ipv4_address, f1_params->my_addr);
+  nc.DU_f1c_ip_address.ipv6 = 0;
+  nc.DU_f1c_ip_address.ipv4 = 1;
+  strcpy(nc.DU_f1c_ip_address.ipv4_address, f1_params->my_addr);
+  nc.DU_f1u_ip_address = strdup(f1u_ip_addr);
   nc.DUport = f1_params->my_portd;
-  LOG_I(GNB_APP,
-        "FIAP: DU_ip4_address in DU %p, strlen %ld\n",
-        nc.DU_f1_ip_address.ipv4_address,
-        strlen(f1_params->my_addr));
+  LOG_I(F1AP,
+        "F1-C DU IPaddr %s, connect to F1-C CU %s, binding GTP to %s\n",
+        nc.DU_f1c_ip_address.ipv4_address,
+        nc.CU_f1_ip_address.ipv4_address,
+        nc.DU_f1u_ip_address);
 
   // sctp_in_streams/sctp_out_streams are given by SCTP layer
   return nc;
@@ -95,7 +93,7 @@ static void f1_setup_request_f1ap(const f1ap_setup_req_t *req)
   }
   memcpy(f1ap_setup->rrc_ver, req->rrc_ver, sizeof(req->rrc_ver));
 
-  F1AP_DU_REGISTER_REQ(msg).net_config = read_DU_IP_config(&RC.nrmac[0]->eth_params_n);
+  F1AP_DU_REGISTER_REQ(msg).net_config = read_DU_IP_config(&RC.nrmac[0]->eth_params_n, RC.nrmac[0]->f1u_addr);
 
   itti_send_msg_to_task(TASK_DU_F1, 0, msg);
 }

openair2/LAYER2/NR_MAC_gNB/nr_mac_gNB.h

@@ -723,6 +723,8 @@ typedef struct f1_config_t {
 typedef struct gNB_MAC_INST_s {
   /// Ethernet parameters for northbound midhaul interface
   eth_params_t                    eth_params_n;
+  /// address for F1U to bind, ports in eth_params_n
+  char *f1u_addr;
   /// Ethernet parameters for fronthaul interface
   eth_params_t                    eth_params_s;
   /// Module