pppos_client: support for PPPAUTHTYPE_NONE

Closes https://github.com/espressif/esp-idf/issues/4616
Closes WIFI-1652

components/esp_netif/lwip/esp_netif_lwip_ppp.c

@@ -246,7 +246,8 @@ esp_err_t esp_netif_ppp_set_auth(esp_netif_t *netif, esp_netif_auth_type_t autht
     struct lwip_ppp_ctx *obj =  netif->lwip_ppp_ctx;
     pppapi_set_auth(obj->ppp, authtype, user, passwd);
 #else
-#error "Unsupported AUTH Negotiation"
+    ESP_LOGE(TAG, "%s failed: No authorisation enabled in menuconfig", __func__);
+    return ESP_ERR_ESP_NETIF_IF_NOT_READY;
 #endif
     return ESP_OK;
 }

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

@@ -661,6 +661,8 @@
 
 #if PPP_DEBUG_ON
 #define PPP_DEBUG                       LWIP_DBG_ON
+#define PRINTPKT_SUPPORT                1
+#define PPP_PROTOCOLNAME                1
 #else
 #define PPP_DEBUG                       LWIP_DBG_OFF
 #endif

examples/protocols/pppos_client/main/Kconfig.projbuild

@@ -19,15 +19,23 @@ menu "Example Configuration"
     config EXAMPLE_MODEM_PPP_AUTH_USERNAME
         string "Set username for authentication"
         default "espressif"
+        depends on !EXAMPLE_MODEM_PPP_AUTH_NONE
         help
             Set username for PPP Authentication.
 
     config EXAMPLE_MODEM_PPP_AUTH_PASSWORD
         string "Set password for authentication"
         default "esp32"
+        depends on !EXAMPLE_MODEM_PPP_AUTH_NONE
         help
             Set password for PPP Authentication.
 
+    config EXAMPLE_MODEM_PPP_AUTH_NONE
+        bool "Skip PPP authentication"
+        default n
+        help
+            Set to true for the PPP client to skip authentication
+
     config EXAMPLE_SEND_MSG
         bool "Short message (SMS)"
         default n

examples/protocols/pppos_client/main/pppos_client_main.c

@@ -217,7 +217,7 @@ void app_main(void)
     esp_netif_auth_type_t auth_type = NETIF_PPP_AUTHTYPE_PAP;
 #elif CONFIG_LWIP_PPP_CHAP_SUPPORT
     esp_netif_auth_type_t auth_type = NETIF_PPP_AUTHTYPE_CHAP;
-#else
+#elif !defined(CONFIG_EXAMPLE_MODEM_PPP_AUTH_NONE)
 #error "Unsupported AUTH Negotiation"
 #endif
     ESP_ERROR_CHECK(esp_netif_init());
@@ -273,7 +273,9 @@ void app_main(void)
     ESP_ERROR_CHECK(dce->get_battery_status(dce, &bcs, &bcl, &voltage));
     ESP_LOGI(TAG, "Battery voltage: %d mV", voltage);
     /* setup PPPoS network parameters */
+#if !defined(CONFIG_EXAMPLE_MODEM_PPP_AUTH_NONE) && (defined(CONFIG_LWIP_PPP_PAP_SUPPORT) || defined(CONFIG_LWIP_PPP_CHAP_SUPPORT))
     esp_netif_ppp_set_auth(esp_netif, auth_type, CONFIG_EXAMPLE_MODEM_PPP_AUTH_USERNAME, CONFIG_EXAMPLE_MODEM_PPP_AUTH_PASSWORD);
+#endif
     void *modem_netif_adapter = esp_modem_netif_setup(dte);
     esp_modem_netif_set_default_handlers(modem_netif_adapter, esp_netif);
     /* attach the modem to the network interface */