+/* if we're restricting writes to the base directory,
+ * check whether the file falls within the dir
+ * returns 1 if OK, otherwise 0
+ */
+static int check_file_access (const char *file, int fd) /* {{{ */
+{
+ char error[CMD_MAX];
+ assert(file != NULL);
+
+ if (!config_write_base_only
+ || fd < 0 /* journal replay */
+ || config_base_dir == NULL)
+ return 1;
+
+ if (strstr(file, "../") != NULL) goto err;
+
+ /* relative paths without "../" are ok */
+ if (*file != '/') return 1;
+
+ /* file must be of the format base + "/" + <1+ char filename> */
+ if (strlen(file) < _config_base_dir_len + 2) goto err;
+ if (strncmp(file, config_base_dir, _config_base_dir_len) != 0) goto err;
+ if (*(file + _config_base_dir_len) != '/') goto err;
+
+ return 1;
+
+err:
+ snprintf(error, sizeof(error)-1, "-1 %s\n", rrd_strerror(EACCES));
+ swrite(fd, error, strlen(error));
+ return 0;
+} /* }}} static int check_file_access */
+