gcoap/forward_proxy: handle timeout case

sys/net/application_layer/gcoap/forward_proxy.c

@@ -87,7 +87,7 @@
     ztimer_set(ZTIMER_MSEC, timer, timeout_ms);
 }
 
 
 void gcoap_forward_proxy_init(void)
 {
     gcoap_register_listener(&forward_proxy_listener);
@@ -276,6 +276,9 @@
     /* No harm done in removing a timer that's not active */
     ztimer_remove(ZTIMER_MSEC, &cep->empty_ack_timer);
     buf_len = coap_get_total_len(pdu);
+    assert(memo->state == GCOAP_MEMO_RESP ||
+           memo->state == GCOAP_MEMO_RESP_TRUNC ||
+           memo->state == GCOAP_MEMO_TIMEOUT);
     if (memo->state == GCOAP_MEMO_RESP) {
         uint8_t req_etag_len = _cep_get_req_etag_len(cep);
 
@@ -304,6 +307,7 @@
             }
 #endif
         }
+        _set_response_type(pdu, _cep_get_response_type(cep));
         /* we do not need to check if valid came from upstream as this is already automatically
          * converted by the client-side to the cached response */
         /* else forward the response packet as-is to the client */
@@ -315,8 +319,13 @@
         assert(buf_len >= (sizeof(*pdu->hdr) + 4U));
         gcoap_resp_init(pdu, (uint8_t *)pdu->hdr, buf_len, COAP_CODE_INTERNAL_SERVER_ERROR);
         coap_opt_finish(pdu, COAP_OPT_FINISH_NONE);
+        _set_response_type(pdu, _cep_get_response_type(cep));
+    }
+    else if (memo->state == GCOAP_MEMO_TIMEOUT) {
+        /* send RST */
+        gcoap_resp_init(pdu, (uint8_t *)pdu->hdr, buf_len, COAP_CODE_EMPTY);
+        coap_opt_finish(pdu, COAP_OPT_FINISH_NONE);
     }
-    _set_response_type(pdu, _cep_get_response_type(cep));
     /* don't use buf_len here, in case the above `gcoap_resp_init`s changed `pdu` */
     _dispatch_msg(pdu->hdr, coap_get_total_len(pdu), &cep->ep, &cep->proxy_ep);
     _free_client_ep(cep);

sys/net/application_layer/gcoap/gcoap.c

@@ -53,7 +53,7 @@
 #define NO_IMMEDIATE_REPLY (-1)
 
 /* End of the range to pick a random timeout */
 #define TIMEOUT_RANGE_END ((uint32_t)CONFIG_COAP_ACK_TIMEOUT_MS * CONFIG_COAP_RANDOM_FACTOR_1000 / 1000)
 
 /* Internal functions */
 static void *_event_loop(void *arg);
@@ -399,7 +399,7 @@
         /* but store the header to keep the token for Observe notifications */
         memcpy(memo->msg.hdr_buf, hdr, sizeof(hdr));
         /* no further retransmissions should be made and
            gcoap_request_memo_get_hdr() has to know how to get the header for Observe notifications */
         memo->send_limit = GCOAP_SEND_LIMIT_NON;
     }
 }
@@ -958,7 +958,7 @@
         memo_pdu->hdr = gcoap_request_memo_get_hdr(memo);
 
         /* verbose debug to catch bugs with request/response matching */
         DEBUG("Seeking memo for remote=%s, tkn=0x%02x%02x%02x%02x%02x%02x%02x%02x, tkl=%"PRIuSIZE"\n",
               ipv6_addr_to_str(_ipv6_addr_str, (ipv6_addr_t *)&remote->addr.ipv6,
                                IPV6_ADDR_MAX_STR_LEN),
               token[0], token[1], token[2], token[3], token[4], token[5], token[6], token[7],
@@ -1045,7 +1045,9 @@
         /* Pass response to handler */
         if (memo->resp_handler) {
             coap_pkt_t req;
-
+            memset(&req, 0, sizeof(req));
+            /* 0 means there is an observe option value */
+            coap_clear_observe(&req);
             req.hdr = gcoap_request_memo_get_hdr(memo);
             memo->resp_handler(memo, &req, NULL);
         }
@@ -1664,7 +1666,7 @@
     const coap_resource_t *resource = last_resource;
 
     while (listener) {
         if ((resource = _match_resource_path_iterator(listener, resource, (const uint8_t *)uri_path))) {
             *last_listener = listener;
             return resource;
         }
@@ -2091,4 +2093,4 @@
     event_post(&_queue, arg);
 }
 
 /** @} */