oc_tls:Free open CoAP transactions in ..free_peer

This change frees CoAP transactions bound to a peer at the upper
layer following the close of a (D)TLS connection or upon a connection
failure when the (D)TLS peer object is freed. This avoids reestablishing
a connection due to retransmissions of a CONfirmable transaction which is
especially helpful in instances where a (D)TLS session cannot be
established (for e.g. incorrect or expired credentials).

Change-Id: Ic12af03430c31d384f2b4a4d444bdaebe97d006e
Signed-off-by: Kishen Maloor <kishen.maloor@intel.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/29389Tested-by: IoTivity Jenkins <jenkins-daemon@iotivity.org>

api/oc_ri.c

@@ -1102,10 +1102,10 @@ oc_ri_invoke_coap_entity_handler(void *request, void *response, uint8_t *buffer,
 static void
 free_client_cb(oc_client_cb_t *cb)
 {
+  oc_list_remove(client_cbs, cb);
 #ifdef OC_BLOCK_WISE
   oc_blockwise_scrub_buffers_for_client_cb(cb);
 #endif /* OC_BLOCK_WISE */
-  oc_list_remove(client_cbs, cb);
   oc_free_string(&cb->uri);
   if (oc_string_len(cb->query)) {
     oc_free_string(&cb->query);

messaging/coap/transactions.c

@@ -242,3 +242,18 @@ coap_free_all_transactions(void)
     t = next;
   }
 }
+
+void
+coap_free_transaction_by_endpoint(oc_endpoint_t *endpoint)
+{
+  coap_transaction_t *t = (coap_transaction_t *)oc_list_head(transactions_list),
+                     *next;
+  while (t != NULL) {
+    next = t->next;
+    if (oc_endpoint_compare(&t->message->endpoint, endpoint) == 0) {
+      coap_clear_transaction(t);
+      break;
+    }
+    t = next;
+  }
+}

messaging/coap/transactions.h

@@ -91,6 +91,7 @@ coap_transaction_t *coap_get_transaction_by_mid(uint16_t mid);
 
 void coap_check_transactions(void);
 void coap_free_all_transactions(void);
+void coap_free_transaction_by_endpoint(oc_endpoint_t *endpoint);
 
 #ifdef __cplusplus
 }

security/oc_tls.c

@@ -202,6 +202,8 @@ oc_tls_free_peer(oc_tls_peer_t *peer, bool inactivity_cb)
 {
   OC_DBG("\noc_tls: removing peer");
 
+  coap_free_transaction_by_endpoint(&peer->endpoint);
+
 #ifdef OC_PKI
   /* Free all roles bound to this (D)TLS session */
   oc_sec_free_roles(peer);