[nrf fromtree] tests: coap_client: Add test for duplicate response

Add test where we receive same UDP packet twice.

Signed-off-by: Seppo Takalo <[email protected]>
(cherry picked from commit 83bc1fc)

Author: SeppoTakalo

tests/net/lib/coap_client/CMakeLists.txt

@@ -26,7 +26,7 @@ add_compile_definitions(CONFIG_COAP_CLIENT_MESSAGE_HEADER_SIZE=48)
 add_compile_definitions(CONFIG_COAP_CLIENT_STACK_SIZE=1024)
 add_compile_definitions(CONFIG_COAP_CLIENT_THREAD_PRIORITY=10)
 add_compile_definitions(CONFIG_COAP_LOG_LEVEL=4)
-add_compile_definitions(CONFIG_COAP_INIT_ACK_TIMEOUT_MS=10)
+add_compile_definitions(CONFIG_COAP_INIT_ACK_TIMEOUT_MS=100)
 add_compile_definitions(CONFIG_COAP_CLIENT_MAX_REQUESTS=2)
 add_compile_definitions(CONFIG_COAP_CLIENT_MAX_INSTANCES=2)
 add_compile_definitions(CONFIG_COAP_MAX_RETRANSMIT=4)

tests/net/lib/coap_client/src/main.c

@@ -335,6 +335,30 @@ static ssize_t z_impl_zsock_recvfrom_custom_fake_echo_next_req(int sock, void *b
 	return sizeof(ack_data);
 }
 
+static ssize_t z_impl_zsock_recvfrom_custom_fake_duplicate_response(int sock, void *buf,
+								    size_t max_len, int flags,
+								    struct sockaddr *src_addr,
+								    socklen_t *addrlen)
+{
+	uint8_t token[TOKEN_OFFSET + COAP_TOKEN_MAX_LEN];
+
+	uint16_t last_message_id = get_next_pending_message_id();
+
+	restore_token(token);
+
+	set_next_pending_message_id(last_message_id);
+	set_next_pending_message_id(last_message_id);
+	store_token(token);
+	store_token(token);
+
+	int ret = z_impl_zsock_recvfrom_custom_fake(sock, buf, max_len, flags, src_addr, addrlen);
+
+	set_socket_events(sock, ZSOCK_POLLIN);
+	z_impl_zsock_recvfrom_fake.custom_fake = z_impl_zsock_recvfrom_custom_fake;
+
+	return ret;
+}
+
 extern void net_coap_init(void);
 
 static void *suite_setup(void)
@@ -829,3 +853,34 @@ ZTEST(coap_client, test_poll_err_after_response)
 	set_socket_events(client.fd, ZSOCK_POLLERR);
 	zassert_not_ok(k_sem_take(&sem1, K_MSEC(MORE_THAN_EXCHANGE_LIFETIME_MS)));
 }
+
+ZTEST(coap_client, test_duplicate_response)
+{
+	int ret = 0;
+	struct k_sem sem;
+	struct sockaddr address = {0};
+	struct coap_client_request client_request = {
+		.method = COAP_METHOD_GET,
+		.confirmable = true,
+		.path = test_path,
+		.fmt = COAP_CONTENT_FORMAT_TEXT_PLAIN,
+		.cb = coap_callback,
+		.payload = short_payload,
+		.len = strlen(short_payload),
+		.user_data = &sem,
+	};
+
+	zassert_ok(k_sem_init(&sem, 0, 2));
+	z_impl_zsock_recvfrom_fake.custom_fake =
+		z_impl_zsock_recvfrom_custom_fake_duplicate_response;
+
+	k_sleep(K_MSEC(1));
+	LOG_INF("Send request");
+	ret = coap_client_req(&client, 0, &address, &client_request, NULL);
+	zassert_true(ret >= 0, "Sending request failed, %d", ret);
+
+	zassert_ok(k_sem_take(&sem, K_MSEC(MORE_THAN_EXCHANGE_LIFETIME_MS)));
+	zassert_equal(last_response_code, COAP_RESPONSE_CODE_OK, "Unexpected response");
+
+	zassert_equal(k_sem_take(&sem, K_MSEC(MORE_THAN_EXCHANGE_LIFETIME_MS)), -EAGAIN, "");
+}