socket-examples: IPv6 related update for examples to set correct scoped id

The scope id must be present when connecting to IPv6 Local Link
address.

examples/protocols/sockets/scripts/tcpclient.py

@@ -12,17 +12,19 @@ import sys
 
 # -----------  Config  ----------
 PORT = 3333
-IP_VERSION = 'IPv4'
-IPV4 = '192.168.0.167'
-IPV6 = 'FE80::32AE:A4FF:FE80:5288'
+IP_VERSION = 'IPv6'
+IPV4 = '192.168.0.42'
+IPV6 = 'fd00:0000:0000:0000:260a:c4ff:fe09:885c'
 # -------------------------------
 
 if IP_VERSION == 'IPv4':
     family_addr = socket.AF_INET
-    host = IPV4
+    addr = (IPV4, PORT)
 elif IP_VERSION == 'IPv6':
     family_addr = socket.AF_INET6
-    host = IPV6
+    for res in socket.getaddrinfo(IPV6, PORT, socket.AF_INET6,
+                                  socket.SOCK_STREAM, socket.SOL_TCP):
+        af, socktype, proto, canonname, addr = res
 else:
     print('IP_VERSION must be IPv4 or IPv6')
     sys.exit(1)
@@ -34,7 +36,7 @@ except socket.error as msg:
         sys.exit(1)
 
 try:
-    sock.connect((host, PORT))
+    sock.connect((IPV6, PORT))
 except socket.error as msg:
         print('Could not open socket: ', msg)
         sock.close()

examples/protocols/sockets/scripts/udpclient.py

@@ -12,17 +12,19 @@ import sys
 
 # -----------  Config  ----------
 PORT = 3333
-IP_VERSION = 'IPv4'
+IP_VERSION = 'IPv6'
 IPV4 = '192.168.0.167'
-IPV6 = 'FE80::32AE:A4FF:FE80:5288'
+IPV6 = 'fe80:0000:0000:0000:260a:c4ff:fe11:a1e0%wlp1s0'
 # -------------------------------
 
 if IP_VERSION == 'IPv4':
-    host = IPV4
+    addr = (IPV4, PORT)
     family_addr = socket.AF_INET
 elif IP_VERSION == 'IPv6':
-    host = IPV6
     family_addr = socket.AF_INET6
+    for res in socket.getaddrinfo(IPV6, PORT, socket.AF_INET6,
+                                  socket.SOCK_DGRAM, socket.SOL_UDP):
+        af, socktype, proto, canonname, addr = res
 else:
     print('IP_VERSION must be IPv4 or IPv6')
     sys.exit(1)
@@ -37,7 +39,7 @@ except socket.error:
 while True:
     msg = input('Enter message to send : ')
     try:
-        sock.sendto(msg.encode(), (host, PORT))
+        sock.sendto(msg.encode(), addr)
         reply, addr = sock.recvfrom(128)
         if not reply:
             break

examples/protocols/sockets/tcp_client/main/tcp_client.c

@@ -54,10 +54,12 @@ static void tcp_client_task(void *pvParameters)
         ip_protocol = IPPROTO_IP;
         inet_ntoa_r(dest_addr.sin_addr, addr_str, sizeof(addr_str) - 1);
 #else // IPV6
-        struct sockaddr_in6 dest_addr;
+        struct sockaddr_in6 dest_addr = { 0 };
         inet6_aton(HOST_IP_ADDR, &dest_addr.sin6_addr);
         dest_addr.sin6_family = AF_INET6;
         dest_addr.sin6_port = htons(PORT);
+        // Setting scope_id to the connecting interface for correct routing if IPv6 Local Link supplied
+        dest_addr.sin6_scope_id = esp_netif_get_netif_impl_index(EXAMPLE_INTERFACE);
         addr_family = AF_INET6;
         ip_protocol = IPPROTO_IPV6;
         inet6_ntoa_r(dest_addr.sin6_addr, addr_str, sizeof(addr_str) - 1);

examples/protocols/sockets/udp_client/main/udp_client.c

@@ -55,10 +55,12 @@ static void udp_client_task(void *pvParameters)
         ip_protocol = IPPROTO_IP;
         inet_ntoa_r(dest_addr.sin_addr, addr_str, sizeof(addr_str) - 1);
 #else // IPV6
-        struct sockaddr_in6 dest_addr;
+        struct sockaddr_in6 dest_addr = { 0 };
         inet6_aton(HOST_IP_ADDR, &dest_addr.sin6_addr);
         dest_addr.sin6_family = AF_INET6;
         dest_addr.sin6_port = htons(PORT);
+        // Setting scope_id to the connecting interface for correct routing if IPv6 Local Link supplied
+        dest_addr.sin6_scope_id = esp_netif_get_netif_impl_index(EXAMPLE_INTERFACE);
         addr_family = AF_INET6;
         ip_protocol = IPPROTO_IPV6;
         inet6_ntoa_r(dest_addr.sin6_addr, addr_str, sizeof(addr_str) - 1);