[network-manager-openvpn/th/ovpn-import-bgo761285: 9/10] properties: write inline certs only at the end of successful import

[Thomas Haller <thaller src gnome org>]

commit 5590a48a17a58a4a96b4a2a90fcb1ed63f6f4957
Author: Thomas Haller <thaller redhat com>
Date:   Fri Jan 29 12:48:53 2016 +0100

    properties: write inline certs only at the end of successful import
    
    Don't write the parsed inline certificates to file right away.
    Instead remember them and only write them out at the very end
    when the parsing proved to be successful. Otherwise, the import
    might still fail afterwards when we already wrote the files.
    
    do_import() writing files to disc is still very ugly, as it is
    intransparent to the user, possibly writes to the wrong location
    (overwriting wrong file) and the user cannot configure it (whether he
    wants a different location or not persistating at all).
    Also, once written certifications will not be automatically
    purged after the connection will be deleted.
    
    Eventually, the import API should become more powerful so that
    inline blobs and filenames can be propagated back and the caller
    can decide what to do with them (e.g. by asking the user).

 properties/import-export.c |  164 ++++++++++++++++++++++++++++++++++++--------
 shared/nm-default.h        |    2 +
 2 files changed, 136 insertions(+), 30 deletions(-)
---
diff --git a/properties/import-export.c b/properties/import-export.c
index c8f0b9d..af1e55b 100644
--- a/properties/import-export.c
+++ b/properties/import-export.c
@@ -532,6 +532,112 @@ parse_http_proxy_auth (const char *default_path,
        return TRUE;
 }
 
+/*****************************************************************************/
+
+typedef struct {
+       char *token;
+       char *path;
+       gsize token_start_line;
+       GString *blob_data;
+} InlineBlobData;
+
+static void
+inline_blob_data_free (InlineBlobData *data)
+{
+       g_return_if_fail (data);
+
+       g_free (data->token);
+       g_free (data->path);
+       g_string_free (data->blob_data, TRUE);
+       g_slice_free (InlineBlobData, data);
+}
+
+static char *
+inline_blob_construct_path (const char *basename, const char *token)
+{
+       gs_free char *f_filename = NULL;
+
+       g_return_val_if_fail (basename, NULL);
+       g_return_val_if_fail (token && token[0], NULL);
+
+       /* Construct file name to write the data in */
+       f_filename = g_strdup_printf ("%s-%s.pem", basename, token);
+
+       if (_nmovpn_test_temp_path)
+               return g_build_filename (_nmovpn_test_temp_path, f_filename, NULL);
+
+       return g_build_filename (g_get_home_dir (), ".cert", f_filename, NULL);
+}
+
+static gboolean
+inline_blob_mkdir_parents (const InlineBlobData *data, const char *filepath, char **out_error)
+{
+       gs_free char *dirname = NULL;
+
+       g_return_val_if_fail (filepath && filepath[0], FALSE);
+       g_return_val_if_fail (out_error && !*out_error, FALSE);
+
+       dirname = g_path_get_dirname (filepath);
+       if (_str_in_set (dirname, "/", "."))
+               return TRUE;
+
+       if (g_file_test (dirname, G_FILE_TEST_IS_DIR))
+               return TRUE;
+
+       if (g_file_test (dirname, G_FILE_TEST_EXISTS)) {
+               *out_error = g_strdup_printf (_("'%s' is not a directory"), dirname);
+               return FALSE;
+       }
+
+       if (!inline_blob_mkdir_parents (data, dirname, out_error))
+               return FALSE;
+
+       if (mkdir (dirname, 0755) < 0) {
+               *out_error = g_strdup_printf (_("cannot create '%s' directory"), dirname);
+               return FALSE;
+       }
+
+       return TRUE;
+}
+
+static gboolean
+inline_blob_write_out (const InlineBlobData *data, GError **error)
+{
+       if (!_nmovpn_test_temp_path) {
+               gs_free char *err_msg = NULL;
+
+               /* in test mode we don't create the certificate directory. */
+               if (!inline_blob_mkdir_parents (data, data->path, &err_msg)) {
+                       g_set_error (error,
+                                    OPENVPN_EDITOR_PLUGIN_ERROR,
+                                    OPENVPN_EDITOR_PLUGIN_ERROR_FAILED,
+                                    _("cannot write <%s> blob from line %ld to file (%s)"),
+                                    data->token,
+                                    (long) data->token_start_line,
+                                    err_msg);
+                       return FALSE;
+               }
+       }
+
+       /* The file is written with the default umask. Whether that is safe enough
+        * to protect (potentally) private data or allows the openvpn service to
+        * access the file later on is left as exercise for the user. */
+       if (!g_file_set_contents (data->path, data->blob_data->str, data->blob_data->len, NULL)) {
+               g_set_error (error,
+                            OPENVPN_EDITOR_PLUGIN_ERROR,
+                            OPENVPN_EDITOR_PLUGIN_ERROR_FAILED,
+                            _("cannot write <%s> blob from line %ld to file '%s'"),
+                            data->token,
+                            (long) data->token_start_line,
+                            data->path);
+               return FALSE;
+       }
+
+       return TRUE;
+}
+
+/*****************************************************************************/
+
 NMConnection *
 do_import (const char *path, const char *contents, gsize contents_len, GError **error)
 {
@@ -552,6 +658,7 @@ do_import (const char *path, const char *contents, gsize contents_len, GError **
        gs_free char *new_contents = NULL;
        const char *last_seen_key_direction = NULL;
        gboolean have_certs, have_ca;
+       GSList *inline_blobs = NULL, *sl_iter;
 
        g_return_val_if_fail (!error || !*error, NULL);
 
@@ -1080,11 +1187,11 @@ do_import (const char *path, const char *contents, gsize contents_len, GError **
                        gs_free char *end_token = NULL;
                        gsize end_token_len;
                        gsize my_contents_cur_line = contents_cur_line;
-                       gs_free char *f_filename = NULL;
-                       gs_free char *f_path = NULL;
+                       char *f_path;
                        const char *key;
                        gboolean can_have_direction = FALSE;
                        GString *blob_data;
+                       InlineBlobData *inline_blob_data;
 
                        if (_streq (token, INLINE_BLOB_CA))
                                key = NM_OPENVPN_KEY_CA;
@@ -1129,40 +1236,29 @@ do_import (const char *path, const char *contents, gsize contents_len, GError **
                                g_string_free (blob_data, TRUE);
                                goto handle_line_error;
                        }
-                       contents_cur_line = my_contents_cur_line;
-
-                       /* Construct file name to write the data in */
-                       f_filename = g_strdup_printf ("%s-%s.pem", basename, token);
-
-                       if (_nmovpn_test_temp_path) {
-                               f_path = g_build_filename (_nmovpn_test_temp_path, f_filename, NULL);
-                       } else {
-                               gs_free char *f_dirname = NULL;
 
-                               f_dirname = g_build_filename (g_get_home_dir (), ".cert", NULL);
-                               f_path = g_build_filename (f_dirname, f_filename, NULL);
+                       /* the latest cert wins... */
+                       for (sl_iter = inline_blobs; sl_iter; sl_iter = sl_iter->next) {
+                               InlineBlobData *d = sl_iter->data;
 
-                               /* Check that dirname exists and is a directory, otherwise create it */
-                               if (!g_file_test (f_dirname, G_FILE_TEST_IS_DIR)) {
-                                       if (!g_file_test (f_dirname, G_FILE_TEST_EXISTS)) {
-                                               if (mkdir (f_dirname, 0755) < 0) {
-                                                       line_error = g_strdup_printf (_("cannot create .cert 
directory for %s blob"), token);
-                                                       goto handle_line_error;
-                                               }
-                                       } else {
-                                               line_error = g_strdup_printf (_(".cert directory is not 
usable for %s blob"), token);
-                                               goto handle_line_error;
-                                       }
+                               if (_streq (d->token, token)) {
+                                       inline_blobs = g_slist_delete_link (inline_blobs, sl_iter);
+                                       inline_blob_data_free (d);
+                                       break;
                                }
                        }
 
-                       /* Write the new file */
-                       if (!g_file_set_contents (f_path, blob_data->str, blob_data->len, error)) {
-                               line_error = g_strdup_printf (_("error writing %s blob to file"), token);
-                               goto handle_line_error;
-                       }
+                       f_path = inline_blob_construct_path (basename, token);
 
-                       g_string_free (blob_data, TRUE);
+                       inline_blob_data = g_slice_new (InlineBlobData);
+                       inline_blob_data->blob_data = blob_data;
+                       inline_blob_data->token_start_line = contents_cur_line;
+                       inline_blob_data->path = f_path;
+                       inline_blob_data->token = token;
+                       token = NULL;
+
+                       inline_blobs = g_slist_prepend (inline_blobs, inline_blob_data);
+                       contents_cur_line = my_contents_cur_line;
 
                        nm_setting_vpn_add_data_item (s_vpn, key, f_path);
                        if (   can_have_direction
@@ -1250,11 +1346,19 @@ handle_line_error:
                }
        }
 
+       inline_blobs = g_slist_reverse (inline_blobs);
+       for (sl_iter = inline_blobs; sl_iter; sl_iter = sl_iter->next) {
+               if (!inline_blob_write_out (sl_iter->data, error))
+                       goto out_error;
+       }
+       g_slist_free_full (inline_blobs, (GDestroyNotify) inline_blob_data_free);
+
        connection_free = NULL;
        g_return_val_if_fail (!error || !*error, connection);
        return connection;
 
 out_error:
+       g_slist_free_full (inline_blobs, (GDestroyNotify) inline_blob_data_free);
        g_return_val_if_fail (!error || *error, NULL);
        return NULL;
 }
diff --git a/shared/nm-default.h b/shared/nm-default.h
index 6990de4..e2677de 100644
--- a/shared/nm-default.h
+++ b/shared/nm-default.h
@@ -72,6 +72,7 @@
 #define NMSettingIPConfig NMSettingIP4Config
 
 #define OPENVPN_EDITOR_PLUGIN_ERROR                     NM_SETTING_VPN_ERROR
+#define OPENVPN_EDITOR_PLUGIN_ERROR_FAILED              NM_SETTING_VPN_ERROR_UNKNOWN
 #define OPENVPN_EDITOR_PLUGIN_ERROR_INVALID_PROPERTY    NM_SETTING_VPN_ERROR_INVALID_PROPERTY
 #define OPENVPN_EDITOR_PLUGIN_ERROR_MISSING_PROPERTY    NM_SETTING_VPN_ERROR_MISSING_PROPERTY
 #define OPENVPN_EDITOR_PLUGIN_ERROR_FILE_NOT_OPENVPN    NM_SETTING_VPN_ERROR_UNKNOWN
@@ -83,6 +84,7 @@
 #include <NetworkManager.h>
 
 #define OPENVPN_EDITOR_PLUGIN_ERROR                     NM_CONNECTION_ERROR
+#define OPENVPN_EDITOR_PLUGIN_ERROR_FAILED              NM_CONNECTION_ERROR_FAILED
 #define OPENVPN_EDITOR_PLUGIN_ERROR_INVALID_PROPERTY    NM_CONNECTION_ERROR_INVALID_PROPERTY
 #define OPENVPN_EDITOR_PLUGIN_ERROR_MISSING_PROPERTY    NM_CONNECTION_ERROR_MISSING_PROPERTY
 #define OPENVPN_EDITOR_PLUGIN_ERROR_FILE_NOT_OPENVPN    NM_CONNECTION_ERROR_FAILED