[pfcp] add send_asr PFCP option (#47)

althea-net · Jan 17, 2024 · 966e77e · 966e77e
1 parent 61d1fee
commit 966e77e
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Showing 4 changed files with 15 additions and 1 deletion.
diff --git a/README.md b/README.md
@@ -9,3 +9,8 @@ Tagged releases (e.g. `v2.4.7`) come straight from plain vanilla `open5gs` and c
 
 ## Number of Served TAC/TAI
 open5gs has a limit of 16 different served TAIs hard-coded in OGS_MAX_NUM_OF_SERVED_TAI. Althea's KeyLTE architecture relies on many more than that: each edge KeyLTE router has its own TAC/TAI. We have currently set OGS_MAX_NUM_OF_SERVED_TAI to 256; this might increase again in the future.
+
+## PFCP Send_ASR Option
+When configuring a node's PFCP connection to another node, you now have the option of adding `send_asr: false` to the configuration yaml. This bool (which defaults to `true`) indicates whether the node should send PFCP AssociationSetupRequests or not.
+
+The reason we need this bool/option is to turn it off for the CPS side. To allow KeyLTE routers to be seamlessly added to the existing CPS without requiring a reboot, we have to define all 256 served TAIs in the CPS configuration. Without this option, the CPS logs are full of errors trying to send ASR messages to KeyLTE routers that don't yet exist.
diff --git a/lib/pfcp/context.c b/lib/pfcp/context.c
@@ -450,6 +450,7 @@ int ogs_pfcp_context_parse_config(const char *local, const char *remote)
                                         const char *hostname[
                                             OGS_MAX_NUM_OF_HOSTNAME];
                                         uint16_t port = self.pfcp_port;
+                                        bool send_asr = 1;
                                         uint16_t tac[OGS_MAX_NUM_OF_TAI] = {0,};
                                         int num_of_tac = 0;
                                         const char *dnn[OGS_MAX_NUM_OF_DNN];
@@ -538,6 +539,10 @@ int ogs_pfcp_context_parse_config(const char *local, const char *remote)
                                                     ogs_yaml_iter_value(
                                                             &remote_iter);
                                                 if (v) port = atoi(v);
+
+                                            } else if (!strcmp(remote_key,
+                                                        "send_asr")) {
+                                                send_asr = ogs_yaml_iter_bool(&remote_iter);
                                             } else if (!strcmp(remote_key,
                                                         "tac")) {
                                                 ogs_yaml_iter_t tac_iter;
@@ -704,6 +709,8 @@ int ogs_pfcp_context_parse_config(const char *local, const char *remote)
                                         ogs_list_add(
                                                 &self.pfcp_peer_list, node);
 
+                                        node->send_asr = send_asr;
+
                                         node->num_of_tac = num_of_tac;
                                         if (num_of_tac != 0)
                                             memcpy(node->tac,

diff --git a/lib/pfcp/context.h b/lib/pfcp/context.h
@@ -96,6 +96,8 @@ typedef struct ogs_pfcp_node_s {
     ogs_timer_t     *t_association; /* timer to retry to associate peer node */
     ogs_timer_t     *t_no_heartbeat; /* heartbeat timer to check aliveness */
 
+    bool            send_asr; /* send association setup request or just listen? */
+
     uint16_t        tac[OGS_MAX_NUM_OF_TAI];
     uint8_t         num_of_tac;
     const char*     dnn[OGS_MAX_NUM_OF_DNN];

diff --git a/lib/pfcp/path.h b/lib/pfcp/path.h
@@ -49,7 +49,7 @@ extern "C" {
         ogs_assert(ogs_pfcp_self()->pfcp_addr || ogs_pfcp_self()->pfcp_addr6); \
         \
         ogs_list_for_each(&ogs_pfcp_self()->pfcp_peer_list, pfcp_node) \
-            pfcp_node_fsm_init(pfcp_node, true); \
+            pfcp_node_fsm_init(pfcp_node, pfcp_node->send_asr); \
         \
     } while(0)