cloud-setup: handle unknown interaces in get_config() for GCP/Azure

The API of mcs_provider_get_config() allows to explicitly request
for certain interfaces (MAC addresses), but it also allows to fetch
any.

That means, the result dictionary will be pre-populated with the
MAC addresses that were requested, but if we encounter an unknown
interface, then that is not a reason to fail.

clients/cloud-setup/nmcs-provider-azure.c

@@ -98,13 +98,12 @@ typedef struct {
     NMCSProviderGetConfigIfaceData *iface_get_config;
     gssize                          iface_idx;
     guint                           n_ips_prefix_pending;
-    char *                          hwaddr;
+    const char *                    hwaddr;
 } AzureIfaceData;
 
 static void
 _azure_iface_data_destroy(AzureIfaceData *iface_data)
 {
-    g_free(iface_data->hwaddr);
     nm_g_slice_free(iface_data);
 }
 
@@ -135,8 +134,7 @@ _get_config_fetch_done_cb(NMHttpClient *  http_client,
     fip_str = g_bytes_get_data(response, NULL);
     iface_data->iface_get_config =
         g_hash_table_lookup(get_config_data->result_dict, iface_data->hwaddr);
-    iface_get_config            = iface_data->iface_get_config;
-    iface_get_config->iface_idx = iface_data->iface_idx;
+    iface_get_config = iface_data->iface_get_config;
 
     if (is_ipv4) {
         if (!nm_utils_parse_inaddr_bin(AF_INET, fip_str, NULL, &tmp_addr)) {
@@ -301,6 +299,7 @@ _get_config_iface_cb(GObject *source, GAsyncResult *result, gpointer user_data)
     NMCSProviderGetConfigTaskData *get_config_data;
     gs_unref_bytes GBytes *response   = NULL;
     AzureIfaceData *       iface_data = user_data;
+    gs_free char *         v_hwaddr   = NULL;
     gs_free_error GError *error       = NULL;
     gs_free const char *  uri         = NULL;
     char                  buf[100];
@@ -315,27 +314,44 @@ _get_config_iface_cb(GObject *source, GAsyncResult *result, gpointer user_data)
     if (error)
         goto out_done;
 
-    iface_data->hwaddr = nmcs_utils_hwaddr_normalize_gbytes(response);
-
-    if (!iface_data->hwaddr)
+    v_hwaddr = nmcs_utils_hwaddr_normalize_gbytes(response);
+    if (!v_hwaddr) {
+        _LOGI("interface[%" G_GSSIZE_FORMAT "]: invalid MAC address returned",
+              iface_data->iface_idx);
+        error = nm_utils_error_new(NM_UTILS_ERROR_UNKNOWN,
+                                   "invalid MAC address for index %" G_GSSIZE_FORMAT,
+                                   iface_data->iface_idx);
         goto out_done;
+    }
 
-    iface_data->iface_get_config =
-        g_hash_table_lookup(get_config_data->result_dict, iface_data->hwaddr);
-
-    if (!iface_data->iface_get_config) {
+    if (!g_hash_table_lookup_extended(get_config_data->result_dict,
+                                      v_hwaddr,
+                                      (gpointer *) &iface_data->hwaddr,
+                                      (gpointer *) &iface_data->iface_get_config)) {
         if (!get_config_data->any) {
-            _LOGD("interface[%" G_GSSIZE_FORMAT "]: ignore hwaddr %s",
-                  iface_data->iface_idx,
-                  iface_data->hwaddr);
+            _LOGD("get-config: skip fetching meta data for %s (%" G_GSSIZE_FORMAT ")",
+                  v_hwaddr,
+                  iface_data->iface_idx);
             goto out_done;
         }
         iface_data->iface_get_config = nmcs_provider_get_config_iface_data_new(FALSE);
         g_hash_table_insert(get_config_data->result_dict,
-                            g_strdup(iface_data->hwaddr),
+                            (char *) (iface_data->hwaddr = g_steal_pointer(&v_hwaddr)),
                             iface_data->iface_get_config);
+    } else {
+        if (iface_data->iface_get_config->iface_idx >= 0) {
+            _LOGI("interface[%" G_GSSIZE_FORMAT "]: duplicate MAC address %s returned",
+                  iface_data->iface_idx,
+                  iface_data->hwaddr);
+            error = nm_utils_error_new(NM_UTILS_ERROR_UNKNOWN,
+                                       "duplicate MAC address for index %" G_GSSIZE_FORMAT,
+                                       iface_data->iface_idx);
+            goto out_done;
+        }
     }
 
+    iface_data->iface_get_config->iface_idx = iface_data->iface_idx;
+
     _LOGD("interface[%" G_GSSIZE_FORMAT "]: found a matching device with hwaddr %s",
           iface_data->iface_idx,
           iface_data->hwaddr);

clients/cloud-setup/nmcs-provider-ec2.c

@@ -269,6 +269,7 @@ _get_config_metadata_ready_cb(GObject *source, GAsyncResult *result, gpointer us
         }
 
         nm_assert(config_iface_data->iface_idx == -1);
+
         config_iface_data->iface_idx = v_mac_data->iface_idx;
 
         _LOGD("get-config: start fetching meta data for #%" G_GSSIZE_FORMAT ", %s (%s)",
@@ -364,6 +365,7 @@ _get_config_metadata_ready_check(long     response_code,
         mac_data->iface_idx = iface_idx_counter++;
         memcpy(mac_data->path, cur_line, cur_line_len + 1u);
 
+        /* here we will ignore duplicate responses. */
         g_hash_table_insert(response_parsed, hwaddr, mac_data);
     }
 

clients/cloud-setup/nmcs-provider-gcp.c

@@ -134,9 +134,8 @@ _get_config_fip_cb(GObject *source, GAsyncResult *result, gpointer user_data)
           iface_data->iface_idx,
           fip_str);
 
-    iface_get_config            = iface_data->iface_get_config;
-    iface_get_config->iface_idx = iface_data->iface_idx;
-    routes_arr                  = iface_get_config->iproutes_arr;
+    iface_get_config = iface_data->iface_get_config;
+    routes_arr       = iface_get_config->iproutes_arr;
 
     route_new = nm_ip_route_new(AF_INET, fip_str, 32, NULL, 100, &error);
     if (error)
@@ -243,13 +242,15 @@ out_error:
 static void
 _get_config_iface_cb(GObject *source, GAsyncResult *result, gpointer user_data)
 {
-    gs_unref_bytes GBytes *response       = NULL;
-    GCPIfaceData *         iface_data     = user_data;
-    gs_free_error GError *         error  = NULL;
-    gs_free const char *           hwaddr = NULL;
-    gs_free const char *           uri    = NULL;
+    gs_unref_bytes GBytes *response         = NULL;
+    GCPIfaceData *         iface_data       = user_data;
+    gs_free_error GError *         error    = NULL;
+    gs_free char *                 v_hwaddr = NULL;
+    const char *                   hwaddr   = NULL;
+    gs_free const char *           uri      = NULL;
     char                           sbuf[100];
     NMCSProviderGetConfigTaskData *get_config_data;
+    gboolean                       is_requested;
 
     nm_http_client_poll_get_finish(NM_HTTP_CLIENT(source), result, NULL, &response, &error);
 
@@ -259,20 +260,51 @@ _get_config_iface_cb(GObject *source, GAsyncResult *result, gpointer user_data)
     get_config_data = iface_data->get_config_data;
 
     if (error)
-        goto out_error;
+        goto out_done;
 
-    hwaddr                       = nmcs_utils_hwaddr_normalize_gbytes(response);
-    iface_data->iface_get_config = g_hash_table_lookup(get_config_data->result_dict, hwaddr);
-    if (!iface_data->iface_get_config) {
-        _LOGI("GCP interface[%" G_GSSIZE_FORMAT "]: did not find a matching device",
+    v_hwaddr = nmcs_utils_hwaddr_normalize_gbytes(response);
+    if (!v_hwaddr) {
+        _LOGI("GCP interface[%" G_GSSIZE_FORMAT "]: invalid MAC address returned",
               iface_data->iface_idx);
         error = nm_utils_error_new(NM_UTILS_ERROR_UNKNOWN,
-                                   "no matching hwaddr found for GCP interface");
-        goto out_error;
+                                   "invalid MAC address for index %" G_GSSIZE_FORMAT,
+                                   iface_data->iface_idx);
+        goto out_done;
     }
 
-    _LOGI("GCP interface[%" G_GSSIZE_FORMAT "]: found a matching device with hwaddr %s",
+    if (!g_hash_table_lookup_extended(get_config_data->result_dict,
+                                      v_hwaddr,
+                                      (gpointer *) &hwaddr,
+                                      (gpointer *) &iface_data->iface_get_config)) {
+        if (!get_config_data->any) {
+            _LOGD("get-config: skip fetching meta data for %s (%" G_GSSIZE_FORMAT ")",
+                  v_hwaddr,
+                  iface_data->iface_idx);
+            goto out_done;
+        }
+        iface_data->iface_get_config = nmcs_provider_get_config_iface_data_new(FALSE);
+        g_hash_table_insert(get_config_data->result_dict,
+                            (char *) (hwaddr = g_steal_pointer(&v_hwaddr)),
+                            iface_data->iface_get_config);
+        is_requested = FALSE;
+    } else {
+        if (iface_data->iface_get_config->iface_idx >= 0) {
+            _LOGI("GCP interface[%" G_GSSIZE_FORMAT "]: duplicate MAC address %s returned",
+                  iface_data->iface_idx,
+                  hwaddr);
+            error = nm_utils_error_new(NM_UTILS_ERROR_UNKNOWN,
+                                       "duplicate MAC address for index %" G_GSSIZE_FORMAT,
+                                       iface_data->iface_idx);
+            goto out_done;
+        }
+        is_requested = TRUE;
+    }
+
+    iface_data->iface_get_config->iface_idx = iface_data->iface_idx;
+
+    _LOGI("GCP interface[%" G_GSSIZE_FORMAT "]: found a %sdevice with hwaddr %s",
           iface_data->iface_idx,
+          is_requested ? "requested " : "",
           hwaddr);
 
     nm_sprintf_buf(sbuf, "%" G_GSSIZE_FORMAT "/forwarded-ips/", iface_data->iface_idx);
@@ -291,7 +323,7 @@ _get_config_iface_cb(GObject *source, GAsyncResult *result, gpointer user_data)
                             iface_data);
     return;
 
-out_error:
+out_done:
     --get_config_data->n_pending;
     _nmcs_provider_get_config_task_maybe_return(get_config_data, g_steal_pointer(&error));
 }

clients/cloud-setup/nmcs-provider.h

@@ -12,11 +12,16 @@
 typedef struct {
     in_addr_t *ipv4s_arr;
     gsize      ipv4s_len;
-    gssize     iface_idx;
-    in_addr_t  cidr_addr;
-    guint8     cidr_prefix;
-    bool       has_ipv4s : 1;
-    bool       has_cidr : 1;
+
+    /* If the interface was seen, get_config() should set this to a
+     * unique, increasing, positive index. If the interface is requested,
+     * it is initialized to -1. */
+    gssize iface_idx;
+
+    in_addr_t cidr_addr;
+    guint8    cidr_prefix;
+    bool      has_ipv4s : 1;
+    bool      has_cidr : 1;
 
     NMIPRoute **iproutes_arr;
     gsize       iproutes_len;