Merge branch 'feature/lwip_support_mdns_queries' into 'master'

lw-IP: support mdns queries

See merge request espressif/esp-idf!5242

components/lwip/Kconfig

@@ -6,6 +6,14 @@ menu "LWIP"
         help
             The name this device will report to other devices on the network
 
+    config LWIP_DNS_SUPPORT_MDNS_QUERIES
+        bool "Enable mDNS queries in resolving host name"
+        default y
+        help
+            If this feature is enabled, standard API such as gethostbyname
+            support .local addresses by sending one shot multicast mDNS
+            query
+
     config LWIP_L2_TO_L3_COPY
         bool "Enable copy between Layer2 and Layer3 packets"
         default n

components/lwip/port/esp32/include/lwipopts.h

@@ -549,6 +549,12 @@
  */
 #define SO_REUSE                        CONFIG_LWIP_SO_REUSE
 
+
+/**
+ * LWIP_DNS_SUPPORT_MDNS_QUERIES==1: Enable mDNS queries in hostname resolution.
+ * This option is set via menuconfig.
+ */
+#define LWIP_DNS_SUPPORT_MDNS_QUERIES   CONFIG_LWIP_DNS_SUPPORT_MDNS_QUERIES
 /**
  * SO_REUSE_RXTOALL==1: Pass a copy of incoming broadcast/multicast packets
  * to all local matches if SO_REUSEADDR is turned on.

examples/protocols/mdns/main/mdns_example_main.c

@@ -29,6 +29,11 @@
 static const char *TAG = "mdns-test";
 static char* generate_hostname(void);
 
+#if CONFIG_MDNS_RESOLVE_TEST_SERVICES == 1
+static void  query_mdns_host_with_gethostbyname(char * host);
+static void  query_mdns_host_with_getaddrinfo(char * host);
+#endif
+
 static void initialise_mdns(void)
 {
     char* hostname = generate_hostname();
@@ -168,6 +173,8 @@ static void mdns_example_task(void *pvParameters)
 #if CONFIG_MDNS_RESOLVE_TEST_SERVICES == 1
     /* Send initial queries that are started by CI tester */
     query_mdns_host("tinytester");
+    query_mdns_host_with_gethostbyname("tinytester-lwip.local");
+    query_mdns_host_with_getaddrinfo("tinytester-lwip.local");
 #endif
 
     while(1) {
@@ -211,3 +218,45 @@ static char* generate_hostname(void)
     return hostname;
 #endif
 }
+
+#if CONFIG_MDNS_RESOLVE_TEST_SERVICES == 1
+/**
+ *  @brief Executes gethostbyname and displays list of resolved addresses.
+ *  Note: This function is used only to test advertised mdns hostnames resolution
+ */
+static void  query_mdns_host_with_gethostbyname(char * host)
+{
+    struct hostent *res = gethostbyname(host);
+    if (res) {
+        unsigned int i = 0;
+        while (res->h_addr_list[i] != NULL) {
+            ESP_LOGI(TAG, "gethostbyname: %s resolved to: %s", host, inet_ntoa(*(struct in_addr *) (res->h_addr_list[i])));
+            i++;
+        }
+    }
+}
+
+/**
+ *  @brief Executes getaddrinfo and displays list of resolved addresses.
+ *  Note: This function is used only to test advertised mdns hostnames resolution
+ */
+static void  query_mdns_host_with_getaddrinfo(char * host)
+{
+    struct addrinfo hints;
+    struct addrinfo * res;
+
+    memset(&hints, 0, sizeof(hints));
+    hints.ai_family = AF_UNSPEC;
+    hints.ai_socktype = SOCK_STREAM;
+
+    if (!getaddrinfo(host, NULL, &hints, &res)) {
+        while (res) {
+            ESP_LOGI(TAG, "getaddrinfo: %s resolved to: %s", host,
+                     res->ai_family == AF_INET?
+                     inet_ntoa(((struct sockaddr_in *) res->ai_addr)->sin_addr):
+                     inet_ntoa(((struct sockaddr_in6 *) res->ai_addr)->sin6_addr));
+            res = res->ai_next;
+        }
+    }
+}
+#endif

examples/protocols/mdns/mdns_example_test.py

@@ -6,7 +6,7 @@ import time
 import struct
 import dpkt
 import dpkt.dns
-from threading import Thread
+from threading import Thread, Event
 
 
 # this is a test case write with tiny-test-fw.
@@ -24,52 +24,78 @@ except ImportError:
 
 import DUT
 
-g_run_server = True
+# g_run_server = True
-g_done = False
+# g_done = False
+stop_mdns_server = Event()
+esp_answered = Event()
+
+
+def get_dns_query_for_esp(esp_host):
+    dns = dpkt.dns.DNS(b'\x00\x00\x01\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x01')
+    dns.qd[0].name = esp_host + u'.local'
+    print("Created query for esp host: {} ".format(dns.__repr__()))
+    return dns.pack()
+
+
+def get_dns_answer_to_mdns(tester_host):
+    dns = dpkt.dns.DNS(b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+    dns.op = dpkt.dns.DNS_QR | dpkt.dns.DNS_AA
+    dns.rcode = dpkt.dns.DNS_RCODE_NOERR
+    arr = dpkt.dns.DNS.RR()
+    arr.cls = dpkt.dns.DNS_IN
+    arr.type = dpkt.dns.DNS_A
+    arr.name = tester_host
+    arr.ip = socket.inet_aton('127.0.0.1')
+    dns. an.append(arr)
+    print("Created answer to mdns query: {} ".format(dns.__repr__()))
+    return dns.pack()
+
+
+def get_dns_answer_to_mdns_lwip(tester_host, id):
+    dns = dpkt.dns.DNS(b"\x5e\x39\x84\x00\x00\x01\x00\x01\x00\x00\x00\x00\x0a\x64\x61\x76\x69\x64"
+                       b"\x2d\x63\x6f\x6d\x70\x05\x6c\x6f\x63\x61\x6c\x00\x00\x01\x00\x01\xc0\x0c"
+                       b"\x00\x01\x00\x01\x00\x00\x00\x0a\x00\x04\xc0\xa8\x0a\x6c")
+    dns.qd[0].name = tester_host
+    dns.an[0].name = tester_host
+    dns.an[0].ip = socket.inet_aton('127.0.0.1')
+    dns.an[0].rdata = socket.inet_aton('127.0.0.1')
+    dns.id = id
+    print("Created answer to mdns (lwip) query: {} ".format(dns.__repr__()))
+    return dns.pack()
 
 
 def mdns_server(esp_host):
-    global g_done
+    global esp_answered
     UDP_IP = "0.0.0.0"
     UDP_PORT = 5353
     MCAST_GRP = '224.0.0.251'
+    TESTER_NAME = u'tinytester.local'
+    TESTER_NAME_LWIP = u'tinytester-lwip.local'
     sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
     sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
     sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)
     sock.bind((UDP_IP,UDP_PORT))
     mreq = struct.pack("4sl", socket.inet_aton(MCAST_GRP), socket.INADDR_ANY)
     sock.setsockopt(socket.IPPROTO_IP, socket.IP_ADD_MEMBERSHIP, mreq)
-    dns = dpkt.dns.DNS(b'\x00\x00\x01\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x01')
     sock.settimeout(30)
-    resp_dns = dpkt.dns.DNS(b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')
+    while not stop_mdns_server.is_set():
-    resp_dns.op = dpkt.dns.DNS_QR | dpkt.dns.DNS_AA
-    resp_dns.rcode = dpkt.dns.DNS_RCODE_NOERR
-    arr = dpkt.dns.DNS.RR()
-    arr.cls = dpkt.dns.DNS_IN
-    arr.type = dpkt.dns.DNS_A
-    arr.name = u'tinytester.local'
-    arr.ip = socket.inet_aton('127.0.0.1')
-    resp_dns. an.append(arr)
-    sock.sendto(resp_dns.pack(),(MCAST_GRP,UDP_PORT))
-    while g_run_server:
         try:
-            m = sock.recvfrom(1024)
+            if not esp_answered.is_set():
-            dns = dpkt.dns.DNS(m[0])
+                sock.sendto(get_dns_query_for_esp(esp_host), (MCAST_GRP,UDP_PORT))
+                time.sleep(0.2)
+            data, addr = sock.recvfrom(1024)
+            dns = dpkt.dns.DNS(data)
             if len(dns.qd) > 0 and dns.qd[0].type == dpkt.dns.DNS_A:
-                if dns.qd[0].name == u'tinytester.local':
+                if dns.qd[0].name == TESTER_NAME:
-                    print(dns.__repr__(),dns.qd[0].name)
+                    print("Received query: {} ".format(dns.__repr__()))
-                    sock.sendto(resp_dns.pack(),(MCAST_GRP,UDP_PORT))
+                    sock.sendto(get_dns_answer_to_mdns(TESTER_NAME), (MCAST_GRP,UDP_PORT))
+                elif dns.qd[0].name == TESTER_NAME_LWIP:
+                    print("Received query: {} ".format(dns.__repr__()))
+                    sock.sendto(get_dns_answer_to_mdns_lwip(TESTER_NAME_LWIP, dns.id), addr)
             if len(dns.an) > 0 and dns.an[0].type == dpkt.dns.DNS_A:
                 if dns.an[0].name == esp_host + u'.local':
-                    print("Received answer esp32-mdns query")
+                    print("Received answer to esp32-mdns query: {}".format(dns.__repr__()))
-                    g_done = True
+                    esp_answered.set()
-                print(dns.an[0].name)
-            dns = dpkt.dns.DNS(b'\x00\x00\x01\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x01')
-            dns.qd[0].name = esp_host + u'.local'
-            sock.sendto(dns.pack(),(MCAST_GRP,UDP_PORT))
-            print("Sending esp32-mdns query")
-            time.sleep(0.5)
-            sock.sendto(resp_dns.pack(),(MCAST_GRP,UDP_PORT))
         except socket.timeout:
             break
         except dpkt.UnpackError:
@@ -78,7 +104,7 @@ def mdns_server(esp_host):
 
 @IDF.idf_example_test(env_tag="Example_WIFI")
 def test_examples_protocol_mdns(env, extra_data):
-    global g_run_server
+    global stop_mdns_server
     """
     steps: |
       1. join AP + init mdns example
@@ -102,22 +128,19 @@ def test_examples_protocol_mdns(env, extra_data):
     try:
         dut1.expect(re.compile(r" sta ip: ([^,]+),"), timeout=30)
     except DUT.ExpectTimeout:
-        g_run_server = False
+        stop_mdns_server.set()
         thread1.join()
         raise ValueError('ENV_TEST_FAILURE: Cannot connect to AP')
     # 3. check the mdns name is accessible
-    start = time.time()
+    if not esp_answered.wait(timeout=30):
-    while (time.time() - start) <= 60:
-        if g_done:
-            break
-        time.sleep(0.5)
-    if g_done is False:
         raise ValueError('Test has failed: did not receive mdns answer within timeout')
     # 4. check DUT output if mdns advertized host is resolved
     try:
         dut1.expect(re.compile(r"mdns-test: Query A: tinytester.local resolved to: 127.0.0.1"), timeout=30)
+        dut1.expect(re.compile(r"mdns-test: gethostbyname: tinytester-lwip.local resolved to: 127.0.0.1"), timeout=30)
+        dut1.expect(re.compile(r"mdns-test: getaddrinfo: tinytester-lwip.local resolved to: 127.0.0.1"), timeout=30)
     finally:
-        g_run_server = False
+        stop_mdns_server.set()
         thread1.join()
 
 

examples/protocols/mdns/sdkconfig.ci

@@ -1,2 +1,3 @@
 CONFIG_MDNS_RESOLVE_TEST_SERVICES=y
 CONFIG_MDNS_ADD_MAC_TO_HOSTNAME=y
+CONFIG_LWIP_DNS_SUPPORT_MDNS_QUERIES=y