wpa_supplicant/dbus/dbus_new_introspect.c

/*
 * wpa_supplicant - D-Bus introspection
 * Copyright (c) 2006, Dan Williams <dcbw@redhat.com> and Red Hat, Inc.
 * Copyright (c) 2009, Witold Sowa <witold.sowa@gmail.com>
 * Copyright (c) 2010, Jouni Malinen <j@w1.fi>
 *
 * This software may be distributed under the terms of the BSD license.
 * See README for more details.
 */

#include "utils/includes.h"

#include "utils/common.h"
#include "utils/list.h"
#include "utils/wpabuf.h"
#include "dbus_common_i.h"
#include "dbus_new_helpers.h"


struct interfaces {
          struct dl_list list;
          char *dbus_interface;
          struct wpabuf *xml;
};


static struct interfaces * add_interface(struct dl_list *list,
                                                   const char *dbus_interface)
{
          struct interfaces *iface;

          dl_list_for_each(iface, list, struct interfaces, list) {
                    if (os_strcmp(iface->dbus_interface, dbus_interface) == 0)
                              return iface; /* already in the list */
          }

          iface = os_zalloc(sizeof(struct interfaces));
          if (!iface)
                    return NULL;
          iface->dbus_interface = os_strdup(dbus_interface);
          iface->xml = wpabuf_alloc(16000);
          if (iface->dbus_interface == NULL || iface->xml == NULL) {
                    os_free(iface->dbus_interface);
                    wpabuf_free(iface->xml);
                    os_free(iface);
                    return NULL;
          }
          wpabuf_printf(iface->xml, "<interface name=\"%s\">", dbus_interface);
          dl_list_add_tail(list, &iface->list);
          return iface;
}


static void add_arg(struct wpabuf *xml, const char *name, const char *type,
                        const char *direction)
{
          wpabuf_printf(xml, "<arg name=\"%s\"", name);
          if (type)
                    wpabuf_printf(xml, " type=\"%s\"", type);
          if (direction)
                    wpabuf_printf(xml, " direction=\"%s\"", direction);
          wpabuf_put_str(xml, "/>");
}


static void add_entry(struct wpabuf *xml, const char *type, const char *name,
                          const struct wpa_dbus_argument *args, int include_dir)
{
          const struct wpa_dbus_argument *arg;

          if (args == NULL || args->name == NULL) {
                    wpabuf_printf(xml, "<%s name=\"%s\"/>", type, name);
                    return;
          }
          wpabuf_printf(xml, "<%s name=\"%s\">", type, name);
          for (arg = args; arg && arg->name; arg++) {
                    add_arg(xml, arg->name, arg->type,
                              include_dir ? (arg->dir == ARG_IN ? "in" : "out") :
                              NULL);
          }
          wpabuf_printf(xml, "</%s>", type);
}


static void add_property(struct wpabuf *xml,
                               const struct wpa_dbus_property_desc *dsc)
{
          wpabuf_printf(xml, "<property name=\"%s\" type=\"%s\" "
                          "access=\"%s%s\"/>",
                          dsc->dbus_property, dsc->type,
                          dsc->getter ? "read" : "",
                          dsc->setter ? "write" : "");
}


static void extract_interfaces_methods(
          struct dl_list *list, const struct wpa_dbus_method_desc *methods)
{
          const struct wpa_dbus_method_desc *dsc;
          struct interfaces *iface;

          for (dsc = methods; dsc && dsc->dbus_method; dsc++) {
                    iface = add_interface(list, dsc->dbus_interface);
                    if (iface)
                              add_entry(iface->xml, "method", dsc->dbus_method,
                                          dsc->args, 1);
          }
}


static void extract_interfaces_signals(
          struct dl_list *list, const struct wpa_dbus_signal_desc *signals)
{
          const struct wpa_dbus_signal_desc *dsc;
          struct interfaces *iface;

          for (dsc = signals; dsc && dsc->dbus_signal; dsc++) {
                    iface = add_interface(list, dsc->dbus_interface);
                    if (iface)
                              add_entry(iface->xml, "signal", dsc->dbus_signal,
                                          dsc->args, 0);
          }
}


static void extract_interfaces_properties(
          struct dl_list *list, const struct wpa_dbus_property_desc *properties)
{
          const struct wpa_dbus_property_desc *dsc;
          struct interfaces *iface;

          for (dsc = properties; dsc && dsc->dbus_property; dsc++) {
                    iface = add_interface(list, dsc->dbus_interface);
                    if (iface)
                              add_property(iface->xml, dsc);
          }
}


/**
 * extract_interfaces - Extract interfaces from methods, signals and props
 * @list: Interface list to be filled
 * @obj_dsc: Description of object from which interfaces will be extracted
 *
 * Iterates over all methods, signals, and properties registered with an
 * object and collects all declared DBus interfaces and create interfaces'
 * node in XML root node for each. Returned list elements contain interface
 * name and XML node of corresponding interface.
 */
static void extract_interfaces(struct dl_list *list,
                                     struct wpa_dbus_object_desc *obj_dsc)
{
          extract_interfaces_methods(list, obj_dsc->methods);
          extract_interfaces_signals(list, obj_dsc->signals);
          extract_interfaces_properties(list, obj_dsc->properties);
}


static void add_interfaces(struct dl_list *list, struct wpabuf *xml)
{
          struct interfaces *iface, *n;

          dl_list_for_each_safe(iface, n, list, struct interfaces, list) {
                    if (wpabuf_len(iface->xml) + 20 < wpabuf_tailroom(xml)) {
                              wpabuf_put_buf(xml, iface->xml);
                              wpabuf_put_str(xml, "</interface>");
                    } else {
                              wpa_printf(MSG_DEBUG,
                                           "dbus: Not enough room for add_interfaces inspect data: tailroom %u, add %u",
                                           (unsigned int) wpabuf_tailroom(xml),
                                           (unsigned int) wpabuf_len(iface->xml));
                    }
                    dl_list_del(&iface->list);
                    wpabuf_free(iface->xml);
                    os_free(iface->dbus_interface);
                    os_free(iface);
          }
}


static void add_child_nodes(struct wpabuf *xml, DBusConnection *con,
                                  const char *path)
{
          char **children;
          int i;

          /* add child nodes to introspection tree */
          dbus_connection_list_registered(con, path, &children);
          for (i = 0; children[i]; i++)
                    wpabuf_printf(xml, "<node name=\"%s\"/>", children[i]);
          dbus_free_string_array(children);
}


static void add_introspectable_interface(struct wpabuf *xml)
{
          wpabuf_printf(xml, "<interface name=\"%s\">"
                          "<method name=\"%s\">"
                          "<arg name=\"data\" type=\"s\" direction=\"out\"/>"
                          "</method>"
                          "</interface>",
                          WPA_DBUS_INTROSPECTION_INTERFACE,
                          WPA_DBUS_INTROSPECTION_METHOD);
}


static void add_properties_interface(struct wpabuf *xml)
{
          wpabuf_printf(xml, "<interface name=\"%s\">",
                          WPA_DBUS_PROPERTIES_INTERFACE);

          wpabuf_printf(xml, "<method name=\"%s\">", WPA_DBUS_PROPERTIES_GET);
          add_arg(xml, "interface", "s", "in");
          add_arg(xml, "propname", "s", "in");
          add_arg(xml, "value", "v", "out");
          wpabuf_put_str(xml, "</method>");

          wpabuf_printf(xml, "<method name=\"%s\">", WPA_DBUS_PROPERTIES_GETALL);
          add_arg(xml, "interface", "s", "in");
          add_arg(xml, "props", "a{sv}", "out");
          wpabuf_put_str(xml, "</method>");

          wpabuf_printf(xml, "<method name=\"%s\">", WPA_DBUS_PROPERTIES_SET);
          add_arg(xml, "interface", "s", "in");
          add_arg(xml, "propname", "s", "in");
          add_arg(xml, "value", "v", "in");
          wpabuf_put_str(xml, "</method>");

          wpabuf_put_str(xml, "</interface>");
}


static void add_wpas_interfaces(struct wpabuf *xml,
                                        struct wpa_dbus_object_desc *obj_dsc)
{
          struct dl_list ifaces;

          dl_list_init(&ifaces);
          extract_interfaces(&ifaces, obj_dsc);
          add_interfaces(&ifaces, xml);
}


/**
 * wpa_dbus_introspect - Responds for Introspect calls on object
 * @message: Message with Introspect call
 * @obj_dsc: Object description on which Introspect was called
 * Returns: Message with introspection result XML string as only argument
 *
 * Iterates over all methods, signals and properties registered with
 * object and generates introspection data for the object as XML string.
 */
DBusMessage * wpa_dbus_introspect(DBusMessage *message,
                                          struct wpa_dbus_object_desc *obj_dsc)
{

          DBusMessage *reply;
          struct wpabuf *xml;

          xml = wpabuf_alloc(30000);
          if (xml == NULL)
                    return NULL;

          wpabuf_put_str(xml, "<?xml version=\"1.0\"?>\n");
          wpabuf_put_str(xml, DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE);
          wpabuf_put_str(xml, "<node>");

          add_introspectable_interface(xml);
          add_properties_interface(xml);
          add_wpas_interfaces(xml, obj_dsc);
          add_child_nodes(xml, obj_dsc->connection,
                              dbus_message_get_path(message));

          wpabuf_put_str(xml, "</node>\n");

          reply = dbus_message_new_method_return(message);
          if (reply) {
                    const char *intro_str = wpabuf_head(xml);

                    dbus_message_append_args(reply, DBUS_TYPE_STRING, &intro_str,
                                                   DBUS_TYPE_INVALID);
          }
          wpabuf_free(xml);

          return reply;
}