1 /*
2  * wpa_supplicant - D-Bus introspection
3  * Copyright (c) 2006, Dan Williams <dcbw@redhat.com> and Red Hat, Inc.
4  * Copyright (c) 2009, Witold Sowa <witold.sowa@gmail.com>
5  * Copyright (c) 2010, Jouni Malinen <j@w1.fi>
6  *
7  * This software may be distributed under the terms of the BSD license.
8  * See README for more details.
9  */
10 
11 #include "utils/includes.h"
12 
13 #include "utils/common.h"
14 #include "utils/list.h"
15 #include "utils/wpabuf.h"
16 #include "dbus_common_i.h"
17 #include "dbus_new_helpers.h"
18 
19 
20 struct interfaces {
21 	struct dl_list list;
22 	char *dbus_interface;
23 	struct wpabuf *xml;
24 };
25 
26 
27 static struct interfaces * add_interface(struct dl_list *list,
28 					 const char *dbus_interface)
29 {
30 	struct interfaces *iface;
31 
32 	dl_list_for_each(iface, list, struct interfaces, list) {
33 		if (os_strcmp(iface->dbus_interface, dbus_interface) == 0)
34 			return iface; /* already in the list */
35 	}
36 
37 	iface = os_zalloc(sizeof(struct interfaces));
38 	if (!iface)
39 		return NULL;
40 	iface->dbus_interface = os_strdup(dbus_interface);
41 	iface->xml = wpabuf_alloc(15000);
42 	if (iface->dbus_interface == NULL || iface->xml == NULL) {
43 		os_free(iface->dbus_interface);
44 		wpabuf_free(iface->xml);
45 		os_free(iface);
46 		return NULL;
47 	}
48 	wpabuf_printf(iface->xml, "<interface name=\"%s\">", dbus_interface);
49 	dl_list_add_tail(list, &iface->list);
50 	return iface;
51 }
52 
53 
54 static void add_arg(struct wpabuf *xml, const char *name, const char *type,
55 		    const char *direction)
56 {
57 	wpabuf_printf(xml, "<arg name=\"%s\"", name);
58 	if (type)
59 		wpabuf_printf(xml, " type=\"%s\"", type);
60 	if (direction)
61 		wpabuf_printf(xml, " direction=\"%s\"", direction);
62 	wpabuf_put_str(xml, "/>");
63 }
64 
65 
66 static void add_entry(struct wpabuf *xml, const char *type, const char *name,
67 		      const struct wpa_dbus_argument *args, int include_dir)
68 {
69 	const struct wpa_dbus_argument *arg;
70 
71 	if (args == NULL || args->name == NULL) {
72 		wpabuf_printf(xml, "<%s name=\"%s\"/>", type, name);
73 		return;
74 	}
75 	wpabuf_printf(xml, "<%s name=\"%s\">", type, name);
76 	for (arg = args; arg && arg->name; arg++) {
77 		add_arg(xml, arg->name, arg->type,
78 			include_dir ? (arg->dir == ARG_IN ? "in" : "out") :
79 			NULL);
80 	}
81 	wpabuf_printf(xml, "</%s>", type);
82 }
83 
84 
85 static void add_property(struct wpabuf *xml,
86 			 const struct wpa_dbus_property_desc *dsc)
87 {
88 	wpabuf_printf(xml, "<property name=\"%s\" type=\"%s\" "
89 		      "access=\"%s%s\"/>",
90 		      dsc->dbus_property, dsc->type,
91 		      dsc->getter ? "read" : "",
92 		      dsc->setter ? "write" : "");
93 }
94 
95 
96 static void extract_interfaces_methods(
97 	struct dl_list *list, const struct wpa_dbus_method_desc *methods)
98 {
99 	const struct wpa_dbus_method_desc *dsc;
100 	struct interfaces *iface;
101 
102 	for (dsc = methods; dsc && dsc->dbus_method; dsc++) {
103 		iface = add_interface(list, dsc->dbus_interface);
104 		if (iface)
105 			add_entry(iface->xml, "method", dsc->dbus_method,
106 				  dsc->args, 1);
107 	}
108 }
109 
110 
111 static void extract_interfaces_signals(
112 	struct dl_list *list, const struct wpa_dbus_signal_desc *signals)
113 {
114 	const struct wpa_dbus_signal_desc *dsc;
115 	struct interfaces *iface;
116 
117 	for (dsc = signals; dsc && dsc->dbus_signal; dsc++) {
118 		iface = add_interface(list, dsc->dbus_interface);
119 		if (iface)
120 			add_entry(iface->xml, "signal", dsc->dbus_signal,
121 				  dsc->args, 0);
122 	}
123 }
124 
125 
126 static void extract_interfaces_properties(
127 	struct dl_list *list, const struct wpa_dbus_property_desc *properties)
128 {
129 	const struct wpa_dbus_property_desc *dsc;
130 	struct interfaces *iface;
131 
132 	for (dsc = properties; dsc && dsc->dbus_property; dsc++) {
133 		iface = add_interface(list, dsc->dbus_interface);
134 		if (iface)
135 			add_property(iface->xml, dsc);
136 	}
137 }
138 
139 
140 /**
141  * extract_interfaces - Extract interfaces from methods, signals and props
142  * @list: Interface list to be filled
143  * @obj_dsc: Description of object from which interfaces will be extracted
144  *
145  * Iterates over all methods, signals, and properties registered with an
146  * object and collects all declared DBus interfaces and create interfaces'
147  * node in XML root node for each. Returned list elements contain interface
148  * name and XML node of corresponding interface.
149  */
150 static void extract_interfaces(struct dl_list *list,
151 			       struct wpa_dbus_object_desc *obj_dsc)
152 {
153 	extract_interfaces_methods(list, obj_dsc->methods);
154 	extract_interfaces_signals(list, obj_dsc->signals);
155 	extract_interfaces_properties(list, obj_dsc->properties);
156 }
157 
158 
159 static void add_interfaces(struct dl_list *list, struct wpabuf *xml)
160 {
161 	struct interfaces *iface, *n;
162 
163 	dl_list_for_each_safe(iface, n, list, struct interfaces, list) {
164 		if (wpabuf_len(iface->xml) + 20 < wpabuf_tailroom(xml)) {
165 			wpabuf_put_buf(xml, iface->xml);
166 			wpabuf_put_str(xml, "</interface>");
167 		} else {
168 			wpa_printf(MSG_DEBUG,
169 				   "dbus: Not enough room for add_interfaces inspect data: tailroom %u, add %u",
170 				   (unsigned int) wpabuf_tailroom(xml),
171 				   (unsigned int) wpabuf_len(iface->xml));
172 		}
173 		dl_list_del(&iface->list);
174 		wpabuf_free(iface->xml);
175 		os_free(iface->dbus_interface);
176 		os_free(iface);
177 	}
178 }
179 
180 
181 static void add_child_nodes(struct wpabuf *xml, DBusConnection *con,
182 			    const char *path)
183 {
184 	char **children;
185 	int i;
186 
187 	/* add child nodes to introspection tree */
188 	dbus_connection_list_registered(con, path, &children);
189 	for (i = 0; children[i]; i++)
190 		wpabuf_printf(xml, "<node name=\"%s\"/>", children[i]);
191 	dbus_free_string_array(children);
192 }
193 
194 
195 static void add_introspectable_interface(struct wpabuf *xml)
196 {
197 	wpabuf_printf(xml, "<interface name=\"%s\">"
198 		      "<method name=\"%s\">"
199 		      "<arg name=\"data\" type=\"s\" direction=\"out\"/>"
200 		      "</method>"
201 		      "</interface>",
202 		      WPA_DBUS_INTROSPECTION_INTERFACE,
203 		      WPA_DBUS_INTROSPECTION_METHOD);
204 }
205 
206 
207 static void add_properties_interface(struct wpabuf *xml)
208 {
209 	wpabuf_printf(xml, "<interface name=\"%s\">",
210 		      WPA_DBUS_PROPERTIES_INTERFACE);
211 
212 	wpabuf_printf(xml, "<method name=\"%s\">", WPA_DBUS_PROPERTIES_GET);
213 	add_arg(xml, "interface", "s", "in");
214 	add_arg(xml, "propname", "s", "in");
215 	add_arg(xml, "value", "v", "out");
216 	wpabuf_put_str(xml, "</method>");
217 
218 	wpabuf_printf(xml, "<method name=\"%s\">", WPA_DBUS_PROPERTIES_GETALL);
219 	add_arg(xml, "interface", "s", "in");
220 	add_arg(xml, "props", "a{sv}", "out");
221 	wpabuf_put_str(xml, "</method>");
222 
223 	wpabuf_printf(xml, "<method name=\"%s\">", WPA_DBUS_PROPERTIES_SET);
224 	add_arg(xml, "interface", "s", "in");
225 	add_arg(xml, "propname", "s", "in");
226 	add_arg(xml, "value", "v", "in");
227 	wpabuf_put_str(xml, "</method>");
228 
229 	wpabuf_put_str(xml, "</interface>");
230 }
231 
232 
233 static void add_wpas_interfaces(struct wpabuf *xml,
234 				struct wpa_dbus_object_desc *obj_dsc)
235 {
236 	struct dl_list ifaces;
237 
238 	dl_list_init(&ifaces);
239 	extract_interfaces(&ifaces, obj_dsc);
240 	add_interfaces(&ifaces, xml);
241 }
242 
243 
244 /**
245  * wpa_dbus_introspect - Responds for Introspect calls on object
246  * @message: Message with Introspect call
247  * @obj_dsc: Object description on which Introspect was called
248  * Returns: Message with introspection result XML string as only argument
249  *
250  * Iterates over all methods, signals and properties registered with
251  * object and generates introspection data for the object as XML string.
252  */
253 DBusMessage * wpa_dbus_introspect(DBusMessage *message,
254 				  struct wpa_dbus_object_desc *obj_dsc)
255 {
256 
257 	DBusMessage *reply;
258 	struct wpabuf *xml;
259 
260 	xml = wpabuf_alloc(20000);
261 	if (xml == NULL)
262 		return NULL;
263 
264 	wpabuf_put_str(xml, "<?xml version=\"1.0\"?>\n");
265 	wpabuf_put_str(xml, DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE);
266 	wpabuf_put_str(xml, "<node>");
267 
268 	add_introspectable_interface(xml);
269 	add_properties_interface(xml);
270 	add_wpas_interfaces(xml, obj_dsc);
271 	add_child_nodes(xml, obj_dsc->connection,
272 			dbus_message_get_path(message));
273 
274 	wpabuf_put_str(xml, "</node>\n");
275 
276 	reply = dbus_message_new_method_return(message);
277 	if (reply) {
278 		const char *intro_str = wpabuf_head(xml);
279 
280 		dbus_message_append_args(reply, DBUS_TYPE_STRING, &intro_str,
281 					 DBUS_TYPE_INVALID);
282 	}
283 	wpabuf_free(xml);
284 
285 	return reply;
286 }
287