[nrf fromtree] tests: coap_client: Improve socket stubs

* Use sys_rand_get() and seed the CoAP library, so our MIDs are
  random.
* Set socket events per socket, so we don't accidentally receive
  on wrong socket
* Reply with correct tokens

Signed-off-by: Seppo Takalo <[email protected]>
(cherry picked from commit ca67f51)

Author: SeppoTakalo

tests/net/lib/coap_client/prj.conf

@@ -1,3 +1,4 @@
 #Testing
 CONFIG_ZTEST=y
 CONFIG_ZTEST_STACK_SIZE=4096
+CONFIG_TEST_RANDOM_GENERATOR=y

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

@@ -11,7 +11,7 @@
 
 #include "stubs.h"
 
-LOG_MODULE_REGISTER(coap_client_test);
+LOG_MODULE_REGISTER(coap_client_test, LOG_LEVEL_DBG);
 
 DEFINE_FFF_GLOBALS;
 #define FFF_FAKES_LIST(FAKE)
@@ -23,11 +23,14 @@ DEFINE_FFF_GLOBALS;
 	(CONFIG_COAP_INIT_ACK_TIMEOUT_MS + CONFIG_COAP_INIT_ACK_TIMEOUT_MS / 2)
 
 #define VALID_MESSAGE_ID BIT(31)
+#define TOKEN_OFFSET          4
 
 static int16_t last_response_code;
 static const char *test_path = "test";
 
 static uint32_t messages_needing_response[2];
+static uint8_t last_token[2][COAP_TOKEN_MAX_LEN];
+static const uint8_t empty_token[COAP_TOKEN_MAX_LEN] = {0};
 
 static struct coap_client client;
 
@@ -61,6 +64,27 @@ static void set_next_pending_message_id(uint16_t id)
 	}
 }
 
+static void store_token(uint8_t *buf)
+{
+	for (int i = 0; i < ARRAY_SIZE(last_token); i++) {
+		if (memcmp(last_token[i], empty_token, 8) == 0) {
+			memcpy(last_token[i], buf + TOKEN_OFFSET, COAP_TOKEN_MAX_LEN);
+			return;
+		}
+	}
+}
+
+static void restore_token(uint8_t *buf)
+{
+	for (int i = 0; i < ARRAY_SIZE(last_token); i++) {
+		if (memcmp(last_token[i], empty_token, 8) != 0) {
+			memcpy(buf + TOKEN_OFFSET, last_token[i], COAP_TOKEN_MAX_LEN);
+			memset(last_token[i], 0, COAP_TOKEN_MAX_LEN);
+			return;
+		}
+	}
+}
+
 static ssize_t z_impl_zsock_recvfrom_custom_fake(int sock, void *buf, size_t max_len, int flags,
 						 struct sockaddr *src_addr, socklen_t *addrlen)
 {
@@ -74,10 +98,11 @@ static ssize_t z_impl_zsock_recvfrom_custom_fake(int sock, void *buf, size_t max
 
 	ack_data[2] = (uint8_t)(last_message_id >> 8);
 	ack_data[3] = (uint8_t)last_message_id;
+	restore_token(ack_data);
 
 	memcpy(buf, ack_data, sizeof(ack_data));
 
-	clear_socket_events(ZSOCK_POLLIN);
+	clear_socket_events(sock, ZSOCK_POLLIN);
 
 	return sizeof(ack_data);
 }
@@ -90,14 +115,14 @@ static ssize_t z_impl_zsock_sendto_custom_fake(int sock, void *buf, size_t len,
 
 	last_message_id |= ((uint8_t *)buf)[2] << 8;
 	last_message_id |= ((uint8_t *)buf)[3];
-
 	type = (((uint8_t *)buf)[0] & 0x30) >> 4;
+	store_token(buf);
 
 	set_next_pending_message_id(last_message_id);
 	LOG_INF("Latest message ID: %d", last_message_id);
 
 	if (type == 0) {
-		set_socket_events(ZSOCK_POLLIN);
+		set_socket_events(sock, ZSOCK_POLLIN);
 	}
 
 	return 1;
@@ -111,6 +136,7 @@ static ssize_t z_impl_zsock_sendto_custom_fake_no_reply(int sock, void *buf, siz
 
 	last_message_id |= ((uint8_t *)buf)[2] << 8;
 	last_message_id |= ((uint8_t *)buf)[3];
+	store_token(buf);
 
 	set_next_pending_message_id(last_message_id);
 	LOG_INF("Latest message ID: %d", last_message_id);
@@ -128,6 +154,7 @@ static ssize_t z_impl_zsock_sendto_custom_fake_echo(int sock, void *buf, size_t
 
 	last_message_id |= ((uint8_t *)buf)[2] << 8;
 	last_message_id |= ((uint8_t *)buf)[3];
+	store_token(buf);
 
 	set_next_pending_message_id(last_message_id);
 	LOG_INF("Latest message ID: %d", last_message_id);
@@ -144,7 +171,7 @@ static ssize_t z_impl_zsock_sendto_custom_fake_echo(int sock, void *buf, size_t
 
 	z_impl_zsock_sendto_fake.custom_fake = z_impl_zsock_sendto_custom_fake;
 
-	set_socket_events(ZSOCK_POLLIN);
+	set_socket_events(sock, ZSOCK_POLLIN);
 
 	return 1;
 }
@@ -160,6 +187,7 @@ static ssize_t z_impl_zsock_sendto_custom_fake_echo_next_req(int sock, void *buf
 
 	last_message_id |= ((uint8_t *)buf)[2] << 8;
 	last_message_id |= ((uint8_t *)buf)[3];
+	store_token(buf);
 
 	set_next_pending_message_id(last_message_id);
 	LOG_INF("Latest message ID: %d", last_message_id);
@@ -184,7 +212,7 @@ static ssize_t z_impl_zsock_sendto_custom_fake_echo_next_req(int sock, void *buf
 
 	z_impl_zsock_sendto_fake.custom_fake = z_impl_zsock_sendto_custom_fake;
 
-	set_socket_events(ZSOCK_POLLIN);
+	set_socket_events(sock, ZSOCK_POLLIN);
 
 	return 1;
 }
@@ -202,10 +230,11 @@ static ssize_t z_impl_zsock_recvfrom_custom_fake_response(int sock, void *buf, s
 
 	ack_data[2] = (uint8_t)(last_message_id >> 8);
 	ack_data[3] = (uint8_t)last_message_id;
+	restore_token(ack_data);
 
 	memcpy(buf, ack_data, sizeof(ack_data));
 
-	clear_socket_events(ZSOCK_POLLIN);
+	clear_socket_events(sock, ZSOCK_POLLIN);
 
 	return sizeof(ack_data);
 }
@@ -216,7 +245,7 @@ static ssize_t z_impl_zsock_recvfrom_custom_fake_empty_ack(int sock, void *buf,
 {
 	uint16_t last_message_id = 0;
 
-	static uint8_t ack_data[] = {0x68, 0x00, 0x00, 0x00, 0x00, 0x00,
+	static uint8_t ack_data[] = {0x60, 0x00, 0x00, 0x00, 0x00, 0x00,
 				     0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
 
 	last_message_id = get_next_pending_message_id();
@@ -247,7 +276,7 @@ static ssize_t z_impl_zsock_recvfrom_custom_fake_unmatching(int sock, void *buf,
 
 	memcpy(buf, ack_data, sizeof(ack_data));
 
-	clear_socket_events(ZSOCK_POLLIN);
+	clear_socket_events(sock, ZSOCK_POLLIN);
 
 	return sizeof(ack_data);
 }
@@ -267,13 +296,14 @@ static ssize_t z_impl_zsock_recvfrom_custom_fake_echo(int sock, void *buf, size_
 
 	ack_data[2] = (uint8_t)(last_message_id >> 8);
 	ack_data[3] = (uint8_t)last_message_id;
+	restore_token(ack_data);
 
 	memcpy(buf, ack_data, sizeof(ack_data));
 
 	z_impl_zsock_recvfrom_fake.custom_fake = z_impl_zsock_recvfrom_custom_fake_response;
 	z_impl_zsock_sendto_fake.custom_fake = z_impl_zsock_sendto_custom_fake_echo;
 
-	clear_socket_events(ZSOCK_POLLIN);
+	clear_socket_events(sock, ZSOCK_POLLIN);
 
 	return sizeof(ack_data);
 }
@@ -293,19 +323,23 @@ static ssize_t z_impl_zsock_recvfrom_custom_fake_echo_next_req(int sock, void *b
 
 	ack_data[2] = (uint8_t)(last_message_id >> 8);
 	ack_data[3] = (uint8_t)last_message_id;
+	restore_token(ack_data);
 
 	memcpy(buf, ack_data, sizeof(ack_data));
 
 	z_impl_zsock_recvfrom_fake.custom_fake = z_impl_zsock_recvfrom_custom_fake_response;
 	z_impl_zsock_sendto_fake.custom_fake = z_impl_zsock_sendto_custom_fake_echo_next_req;
 
-	clear_socket_events(ZSOCK_POLLIN);
+	clear_socket_events(sock, ZSOCK_POLLIN);
 
 	return sizeof(ack_data);
 }
 
+extern void net_coap_init(void);
+
 static void *suite_setup(void)
 {
+	net_coap_init();
 	coap_client_init(&client, NULL);
 
 	return NULL;
@@ -315,20 +349,28 @@ static void test_setup(void *data)
 {
 	int i;
 
+	k_mutex_lock(&client.lock, K_FOREVER);
+
 	/* Register resets */
 	DO_FOREACH_FAKE(RESET_FAKE);
 	/* reset common FFF internal structures */
 	FFF_RESET_HISTORY();
 
 	z_impl_zsock_recvfrom_fake.custom_fake = z_impl_zsock_recvfrom_custom_fake;
 	z_impl_zsock_sendto_fake.custom_fake = z_impl_zsock_sendto_custom_fake;
-	clear_socket_events(ZSOCK_POLLIN | ZSOCK_POLLOUT | ZSOCK_POLLERR);
+	clear_socket_events(0, ZSOCK_POLLIN | ZSOCK_POLLOUT | ZSOCK_POLLERR);
+	clear_socket_events(1, ZSOCK_POLLIN | ZSOCK_POLLOUT | ZSOCK_POLLERR);
 
 	for (i = 0; i < ARRAY_SIZE(messages_needing_response); i++) {
 		messages_needing_response[i] = 0;
 	}
 
+	memset(&client.requests, 0, sizeof(client.requests));
+	memset(last_token, 0, sizeof(last_token));
+
 	last_response_code = 0;
+
+	k_mutex_unlock(&client.lock);
 }
 
 void coap_callback(int16_t code, size_t offset, const uint8_t *payload, size_t len, bool last_block,
@@ -396,7 +438,7 @@ ZTEST(coap_client, test_resend_request)
 	ret = coap_client_req(&client, 0, &address, &client_request, NULL);
 	zassert_true(ret >= 0, "Sending request failed, %d", ret);
 	k_sleep(K_MSEC(MORE_THAN_ACK_TIMEOUT_MS));
-	set_socket_events(ZSOCK_POLLIN | ZSOCK_POLLOUT);
+	set_socket_events(client.fd, ZSOCK_POLLIN | ZSOCK_POLLOUT);
 
 	k_sleep(K_MSEC(MORE_THAN_EXCHANGE_LIFETIME_MS));
 	zassert_equal(last_response_code, COAP_RESPONSE_CODE_OK, "Unexpected response");
@@ -551,7 +593,7 @@ ZTEST(coap_client, test_no_response)
 	client_request.len = strlen(short_payload);
 
 	z_impl_zsock_sendto_fake.custom_fake = z_impl_zsock_sendto_custom_fake_no_reply;
-	set_socket_events(ZSOCK_POLLOUT);
+	set_socket_events(client.fd, ZSOCK_POLLOUT);
 
 	k_sleep(K_MSEC(1));
 
@@ -628,15 +670,15 @@ ZTEST(coap_client, test_multiple_requests)
 	ret = coap_client_req(&client, 0, &address, &req2, NULL);
 	zassert_true(ret >= 0, "Sending request failed, %d", ret);
 
-	set_socket_events(ZSOCK_POLLIN);
+	set_socket_events(client.fd, ZSOCK_POLLIN);
 	while (last_response_code == 0 && retry > 0) {
 		retry--;
 		k_sleep(K_MSEC(1));
 	}
 	zassert_equal(last_response_code, COAP_RESPONSE_CODE_OK, "Unexpected response");
 
 	last_response_code = 0;
-	set_socket_events(ZSOCK_POLLIN);
+	set_socket_events(client.fd, ZSOCK_POLLIN);
 	zassert_ok(k_sem_take(&sem1, K_MSEC(MORE_THAN_EXCHANGE_LIFETIME_MS)));
 	zassert_ok(k_sem_take(&sem2, K_MSEC(MORE_THAN_EXCHANGE_LIFETIME_MS)));
 	zassert_equal(last_response_code, COAP_RESPONSE_CODE_OK, "Unexpected response");
@@ -665,7 +707,7 @@ ZTEST(coap_client, test_unmatching_tokens)
 	client_request.len = strlen(short_payload);
 
 	z_impl_zsock_recvfrom_fake.custom_fake = z_impl_zsock_recvfrom_custom_fake_unmatching;
-	set_socket_events(ZSOCK_POLLIN | ZSOCK_POLLOUT);
+	set_socket_events(client.fd, ZSOCK_POLLIN | ZSOCK_POLLOUT);
 
 	k_sleep(K_MSEC(1));
 
@@ -681,9 +723,6 @@ ZTEST(coap_client, test_multiple_clients)
 {
 	int ret;
 	int retry = MORE_THAN_EXCHANGE_LIFETIME_MS;
-	static struct coap_client client2 = {
-		.fd = 2,
-	};
 	struct k_sem sem1, sem2;
 	struct sockaddr address = {0};
 	struct coap_client_request req1 = {
@@ -710,17 +749,17 @@ ZTEST(coap_client, test_multiple_clients)
 	k_sleep(K_MSEC(1));
 
 	LOG_INF("Sending requests");
-	ret = coap_client_req(&client, 1, &address, &req1, NULL);
+	ret = coap_client_req(&client, client.fd, &address, &req1, NULL);
 	zassert_true(ret >= 0, "Sending request failed, %d", ret);
 
-	ret = coap_client_req(&client2, 2, &address, &req2, NULL);
+	ret = coap_client_req(&client2, client2.fd, &address, &req2, NULL);
 	zassert_true(ret >= 0, "Sending request failed, %d", ret);
 
 	while (last_response_code == 0 && retry > 0) {
 		retry--;
 		k_sleep(K_MSEC(1));
 	}
-	set_socket_events(ZSOCK_POLLIN);
+	set_socket_events(client2.fd, ZSOCK_POLLIN);
 
 	k_sleep(K_SECONDS(1));
 
@@ -746,7 +785,7 @@ ZTEST(coap_client, test_poll_err)
 	};
 
 	z_impl_zsock_sendto_fake.custom_fake = z_impl_zsock_sendto_custom_fake_no_reply;
-	set_socket_events(ZSOCK_POLLERR);
+	set_socket_events(client.fd, ZSOCK_POLLERR);
 
 	k_sleep(K_MSEC(1));
 
@@ -776,7 +815,7 @@ ZTEST(coap_client, test_poll_err_after_response)
 
 	zassert_ok(k_sem_init(&sem1, 0, 1));
 	z_impl_zsock_sendto_fake.custom_fake = z_impl_zsock_sendto_custom_fake_no_reply;
-	set_socket_events(ZSOCK_POLLIN);
+	set_socket_events(client.fd, ZSOCK_POLLIN);
 
 	k_sleep(K_MSEC(1));
 
@@ -787,6 +826,6 @@ ZTEST(coap_client, test_poll_err_after_response)
 	zassert_ok(k_sem_take(&sem1, K_MSEC(MORE_THAN_EXCHANGE_LIFETIME_MS)));
 	zassert_equal(last_response_code, COAP_RESPONSE_CODE_OK, "Unexpected response");
 
-	set_socket_events(ZSOCK_POLLERR);
+	set_socket_events(client.fd, ZSOCK_POLLERR);
 	zassert_not_ok(k_sem_take(&sem1, K_MSEC(MORE_THAN_EXCHANGE_LIFETIME_MS)));
 }

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

@@ -10,7 +10,6 @@
 LOG_MODULE_DECLARE(coap_client_test);
 
 DEFINE_FAKE_VALUE_FUNC(uint32_t, z_impl_sys_rand32_get);
-DEFINE_FAKE_VOID_FUNC(z_impl_sys_rand_get, void *, size_t);
 DEFINE_FAKE_VALUE_FUNC(ssize_t, z_impl_zsock_recvfrom, int, void *, size_t, int, struct sockaddr *,
 		       socklen_t *);
 DEFINE_FAKE_VALUE_FUNC(ssize_t, z_impl_zsock_sendto, int, void *, size_t, int,
@@ -22,29 +21,26 @@ struct zsock_pollfd {
 	short revents;
 };
 
-static short my_events;
+static short my_events[NUM_FD];
 
-void set_socket_events(short events)
+void set_socket_events(int fd, short events)
 {
-	my_events |= events;
+	__ASSERT_NO_MSG(fd < NUM_FD);
+	my_events[fd] |= events;
 }
 
-void clear_socket_events(short events)
+void clear_socket_events(int fd, short events)
 {
-	my_events &= ~events;
-}
-
-int z_impl_zsock_socket(int family, int type, int proto)
-{
-	return 0;
+	my_events[fd] &= ~events;
 }
 
 int z_impl_zsock_poll(struct zsock_pollfd *fds, int nfds, int poll_timeout)
 {
 	int events = 0;
 	k_sleep(K_MSEC(1));
 	for (int i = 0; i < nfds; i++) {
-		fds[i].revents = my_events & (fds[i].events | ZSOCK_POLLERR | ZSOCK_POLLHUP);
+		fds[i].revents =
+			my_events[fds[i].fd] & (fds[i].events | ZSOCK_POLLERR | ZSOCK_POLLHUP);
 		if (fds[i].revents) {
 			events++;
 		}