[thirdparty/systemd.git] / src / libsystemd / sd-bus / bus-introspect.c

/* SPDX-License-Identifier: LGPL-2.1-or-later */

#include <stdio.h>

#include "sd-bus-vtable.h"

#include "bus-internal.h"
#include "bus-introspect.h"
#include "bus-objects.h"
#include "bus-signature.h"
#include "memstream-util.h"
#include "ordered-set.h"
#include "string-util.h"

#define BUS_INTROSPECT_DOCTYPE                                       \
        "<!DOCTYPE node PUBLIC \"-//freedesktop//DTD D-BUS Object Introspection 1.0//EN\"\n" \
        "\"https://www.freedesktop.org/standards/dbus/1.0/introspect.dtd\">\n"

#define BUS_INTROSPECT_INTERFACE_PEER                                \
        " <interface name=\"org.freedesktop.DBus.Peer\">\n"             \
        "  <method name=\"Ping\"/>\n"                                   \
        "  <method name=\"GetMachineId\">\n"                            \
        "   <arg type=\"s\" name=\"machine_uuid\" direction=\"out\"/>\n" \
        "  </method>\n"                                                 \
        " </interface>\n"

#define BUS_INTROSPECT_INTERFACE_INTROSPECTABLE                      \
        " <interface name=\"org.freedesktop.DBus.Introspectable\">\n"   \
        "  <method name=\"Introspect\">\n"                              \
        "   <arg name=\"xml_data\" type=\"s\" direction=\"out\"/>\n"    \
        "  </method>\n"                                                 \
        " </interface>\n"

#define BUS_INTROSPECT_INTERFACE_PROPERTIES                          \
        " <interface name=\"org.freedesktop.DBus.Properties\">\n"       \
        "  <method name=\"Get\">\n"                                     \
        "   <arg name=\"interface_name\" direction=\"in\" type=\"s\"/>\n" \
        "   <arg name=\"property_name\" direction=\"in\" type=\"s\"/>\n" \
        "   <arg name=\"value\" direction=\"out\" type=\"v\"/>\n"       \
        "  </method>\n"                                                 \
        "  <method name=\"GetAll\">\n"                                  \
        "   <arg name=\"interface_name\" direction=\"in\" type=\"s\"/>\n" \
        "   <arg name=\"props\" direction=\"out\" type=\"a{sv}\"/>\n"   \
        "  </method>\n"                                                 \
        "  <method name=\"Set\">\n"                                     \
        "   <arg name=\"interface_name\" direction=\"in\" type=\"s\"/>\n" \
        "   <arg name=\"property_name\" direction=\"in\" type=\"s\"/>\n" \
        "   <arg name=\"value\" direction=\"in\" type=\"v\"/>\n"        \
        "  </method>\n"                                                 \
        "  <signal name=\"PropertiesChanged\">\n"                       \
        "   <arg type=\"s\" name=\"interface_name\"/>\n"                \
        "   <arg type=\"a{sv}\" name=\"changed_properties\"/>\n"        \
        "   <arg type=\"as\" name=\"invalidated_properties\"/>\n"       \
        "  </signal>\n"                                                 \
        " </interface>\n"

#define BUS_INTROSPECT_INTERFACE_OBJECT_MANAGER                      \
        " <interface name=\"org.freedesktop.DBus.ObjectManager\">\n"    \
        "  <method name=\"GetManagedObjects\">\n"                       \
        "   <arg type=\"a{oa{sa{sv}}}\" name=\"object_paths_interfaces_and_properties\" direction=\"out\"/>\n" \
        "  </method>\n"                                                 \
        "  <signal name=\"InterfacesAdded\">\n"                         \
        "   <arg type=\"o\" name=\"object_path\"/>\n"                   \
        "   <arg type=\"a{sa{sv}}\" name=\"interfaces_and_properties\"/>\n" \
        "  </signal>\n"                                                 \
        "  <signal name=\"InterfacesRemoved\">\n"                       \
        "   <arg type=\"o\" name=\"object_path\"/>\n"                   \
        "   <arg type=\"as\" name=\"interfaces\"/>\n"                   \
        "  </signal>\n"                                                 \
        " </interface>\n"

int introspect_begin(BusIntrospect *i, bool trusted) {
        FILE *f;

        assert(i);

        *i = (BusIntrospect) {
                .trusted = trusted,
        };

        f = memstream_init(&i->m);
        if (!f)
                return -ENOMEM;

        fputs(BUS_INTROSPECT_DOCTYPE
              "<node>\n", f);

        return 0;
}

int introspect_write_default_interfaces(BusIntrospect *i, bool object_manager) {
        assert(i);
        assert(i->m.f);

        fputs(BUS_INTROSPECT_INTERFACE_PEER
              BUS_INTROSPECT_INTERFACE_INTROSPECTABLE
              BUS_INTROSPECT_INTERFACE_PROPERTIES, i->m.f);

        if (object_manager)
                fputs(BUS_INTROSPECT_INTERFACE_OBJECT_MANAGER, i->m.f);

        return 0;
}

static int set_interface_name(BusIntrospect *i, const char *interface_name) {
        assert(i);
        assert(i->m.f);

        if (streq_ptr(i->interface_name, interface_name))
                return 0;

        if (i->interface_name)
                fputs(" </interface>\n", i->m.f);

        if (interface_name)
                fprintf(i->m.f, " <interface name=\"%s\">\n", interface_name);

        return free_and_strdup(&i->interface_name, interface_name);
}

int introspect_write_child_nodes(BusIntrospect *i, OrderedSet *s, const char *prefix) {
        char *node;

        assert(i);
        assert(i->m.f);
        assert(prefix);

        assert_se(set_interface_name(i, NULL) >= 0);

        while ((node = ordered_set_steal_first(s))) {
                const char *e;

                e = object_path_startswith(node, prefix);
                if (e && e[0])
                        fprintf(i->m.f, " <node name=\"%s\"/>\n", e);

                free(node);
        }

        return 0;
}

static void introspect_write_flags(BusIntrospect *i, int type, uint64_t flags) {
        assert(i);
        assert(i->m.f);

        if (flags & SD_BUS_VTABLE_DEPRECATED)
                fputs("   <annotation name=\"org.freedesktop.DBus.Deprecated\" value=\"true\"/>\n", i->m.f);

        if (type == _SD_BUS_VTABLE_METHOD && (flags & SD_BUS_VTABLE_METHOD_NO_REPLY))
                fputs("   <annotation name=\"org.freedesktop.DBus.Method.NoReply\" value=\"true\"/>\n", i->m.f);

        if (IN_SET(type, _SD_BUS_VTABLE_PROPERTY, _SD_BUS_VTABLE_WRITABLE_PROPERTY)) {
                if (flags & SD_BUS_VTABLE_PROPERTY_EXPLICIT)
                        fputs("   <annotation name=\"org.freedesktop.systemd1.Explicit\" value=\"true\"/>\n", i->m.f);

                if (flags & SD_BUS_VTABLE_PROPERTY_CONST)
                        fputs("   <annotation name=\"org.freedesktop.DBus.Property.EmitsChangedSignal\" value=\"const\"/>\n", i->m.f);
                else if (flags & SD_BUS_VTABLE_PROPERTY_EMITS_INVALIDATION)
                        fputs("   <annotation name=\"org.freedesktop.DBus.Property.EmitsChangedSignal\" value=\"invalidates\"/>\n", i->m.f);
                else if (!(flags & SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE))
                        fputs("   <annotation name=\"org.freedesktop.DBus.Property.EmitsChangedSignal\" value=\"false\"/>\n", i->m.f);
        }

        if (!i->trusted &&
            IN_SET(type, _SD_BUS_VTABLE_METHOD, _SD_BUS_VTABLE_WRITABLE_PROPERTY) &&
            !(flags & SD_BUS_VTABLE_UNPRIVILEGED))
                fputs("   <annotation name=\"org.freedesktop.systemd1.Privileged\" value=\"true\"/>\n", i->m.f);
}

/* Note that "names" is both an input and an output parameter. It initially points to the first argument name in a
   NULL-separated list of strings, and is then advanced with each argument, and the resulting pointer is returned. */
static int introspect_write_arguments(BusIntrospect *i, const char *signature, const char **names, const char *direction) {
        int r;

        assert(i);
        assert(i->m.f);

        for (;;) {
                size_t l;

                if (!*signature)
                        return 0;

                r = signature_element_length(signature, &l);
                if (r < 0)
                        return r;

                fprintf(i->m.f, "   <arg type=\"%.*s\"", (int) l, signature);

                if (**names != '\0') {
                        fprintf(i->m.f, " name=\"%s\"", *names);
                        *names += strlen(*names) + 1;
                }

                if (direction)
                        fprintf(i->m.f, " direction=\"%s\"/>\n", direction);
                else
                        fputs("/>\n", i->m.f);

                signature += l;
        }
}

int introspect_write_interface(
                BusIntrospect *i,
                const char *interface_name,
                const sd_bus_vtable *v) {

        const sd_bus_vtable *vtable = ASSERT_PTR(v);
        const char *names = "";
        int r;

        assert(i);
        assert(i->m.f);
        assert(interface_name);

        r = set_interface_name(i, interface_name);
        if (r < 0)
                return r;

        for (; v->type != _SD_BUS_VTABLE_END; v = bus_vtable_next(vtable, v)) {

                /* Ignore methods, signals and properties that are
                 * marked "hidden", but do show the interface
                 * itself */

                if (v->type != _SD_BUS_VTABLE_START && (v->flags & SD_BUS_VTABLE_HIDDEN))
                        continue;

                switch (v->type) {

                case _SD_BUS_VTABLE_START:
                        if (v->flags & SD_BUS_VTABLE_DEPRECATED)
                                fputs("  <annotation name=\"org.freedesktop.DBus.Deprecated\" value=\"true\"/>\n", i->m.f);
                        break;

                case _SD_BUS_VTABLE_METHOD:
                        fprintf(i->m.f, "  <method name=\"%s\">\n", v->x.method.member);
                        if (bus_vtable_has_names(vtable))
                                names = strempty(v->x.method.names);
                        introspect_write_arguments(i, strempty(v->x.method.signature), &names, "in");
                        introspect_write_arguments(i, strempty(v->x.method.result), &names, "out");
                        introspect_write_flags(i, v->type, v->flags);
                        fputs("  </method>\n", i->m.f);
                        break;

                case _SD_BUS_VTABLE_PROPERTY:
                case _SD_BUS_VTABLE_WRITABLE_PROPERTY:
                        fprintf(i->m.f, "  <property name=\"%s\" type=\"%s\" access=\"%s\">\n",
                                v->x.property.member,
                                v->x.property.signature,
                                v->type == _SD_BUS_VTABLE_WRITABLE_PROPERTY ? "readwrite" : "read");
                        introspect_write_flags(i, v->type, v->flags);
                        fputs("  </property>\n", i->m.f);
                        break;

                case _SD_BUS_VTABLE_SIGNAL:
                        fprintf(i->m.f, "  <signal name=\"%s\">\n", v->x.signal.member);
                        if (bus_vtable_has_names(vtable))
                                names = strempty(v->x.signal.names);
                        introspect_write_arguments(i, strempty(v->x.signal.signature), &names, NULL);
                        introspect_write_flags(i, v->type, v->flags);
                        fputs("  </signal>\n", i->m.f);
                        break;
                }

        }

        return 0;
}

int introspect_finish(BusIntrospect *i, char **ret) {
        assert(i);
        assert(i->m.f);

        assert_se(set_interface_name(i, NULL) >= 0);

        fputs("</node>\n", i->m.f);

        return memstream_finalize(&i->m, ret, NULL);
}

void introspect_done(BusIntrospect *i) {
        assert(i);

        /* Normally introspect_finish() does all the work, this is just a backup for error paths */

        memstream_done(&i->m);
        free(i->interface_name);
}
Commit	Line	Data
	1	/* SPDX-License-Identifier: LGPL-2.1-or-later */
	2
	3	#include <stdio.h>
	4
	5	#include "sd-bus-vtable.h"
	6
	7	#include "bus-internal.h"
	8	#include "bus-introspect.h"
	9	#include "bus-objects.h"
	10	#include "bus-signature.h"
	11	#include "memstream-util.h"
	12	#include "ordered-set.h"
	13	#include "string-util.h"
	14
	15	#define BUS_INTROSPECT_DOCTYPE \
	16	"<!DOCTYPE node PUBLIC \"-//freedesktop//DTD D-BUS Object Introspection 1.0//EN\"\n" \
	17	"\"https://www.freedesktop.org/standards/dbus/1.0/introspect.dtd\">\n"
	18
	19	#define BUS_INTROSPECT_INTERFACE_PEER \
	20	" <interface name=\"org.freedesktop.DBus.Peer\">\n" \
	21	" <method name=\"Ping\"/>\n" \
	22	" <method name=\"GetMachineId\">\n" \
	23	" <arg type=\"s\" name=\"machine_uuid\" direction=\"out\"/>\n" \
	24	" </method>\n" \
	25	" </interface>\n"
	26
	27	#define BUS_INTROSPECT_INTERFACE_INTROSPECTABLE \
	28	" <interface name=\"org.freedesktop.DBus.Introspectable\">\n" \
	29	" <method name=\"Introspect\">\n" \
	30	" <arg name=\"xml_data\" type=\"s\" direction=\"out\"/>\n" \
	31	" </method>\n" \
	32	" </interface>\n"
	33
	34	#define BUS_INTROSPECT_INTERFACE_PROPERTIES \
	35	" <interface name=\"org.freedesktop.DBus.Properties\">\n" \
	36	" <method name=\"Get\">\n" \
	37	" <arg name=\"interface_name\" direction=\"in\" type=\"s\"/>\n" \
	38	" <arg name=\"property_name\" direction=\"in\" type=\"s\"/>\n" \
	39	" <arg name=\"value\" direction=\"out\" type=\"v\"/>\n" \
	40	" </method>\n" \
	41	" <method name=\"GetAll\">\n" \
	42	" <arg name=\"interface_name\" direction=\"in\" type=\"s\"/>\n" \
	43	" <arg name=\"props\" direction=\"out\" type=\"a{sv}\"/>\n" \
	44	" </method>\n" \
	45	" <method name=\"Set\">\n" \
	46	" <arg name=\"interface_name\" direction=\"in\" type=\"s\"/>\n" \
	47	" <arg name=\"property_name\" direction=\"in\" type=\"s\"/>\n" \
	48	" <arg name=\"value\" direction=\"in\" type=\"v\"/>\n" \
	49	" </method>\n" \
	50	" <signal name=\"PropertiesChanged\">\n" \
	51	" <arg type=\"s\" name=\"interface_name\"/>\n" \
	52	" <arg type=\"a{sv}\" name=\"changed_properties\"/>\n" \
	53	" <arg type=\"as\" name=\"invalidated_properties\"/>\n" \
	54	" </signal>\n" \
	55	" </interface>\n"
	56
	57	#define BUS_INTROSPECT_INTERFACE_OBJECT_MANAGER \
	58	" <interface name=\"org.freedesktop.DBus.ObjectManager\">\n" \
	59	" <method name=\"GetManagedObjects\">\n" \
	60	" <arg type=\"a{oa{sa{sv}}}\" name=\"object_paths_interfaces_and_properties\" direction=\"out\"/>\n" \
	61	" </method>\n" \
	62	" <signal name=\"InterfacesAdded\">\n" \
	63	" <arg type=\"o\" name=\"object_path\"/>\n" \
	64	" <arg type=\"a{sa{sv}}\" name=\"interfaces_and_properties\"/>\n" \
	65	" </signal>\n" \
	66	" <signal name=\"InterfacesRemoved\">\n" \
	67	" <arg type=\"o\" name=\"object_path\"/>\n" \
	68	" <arg type=\"as\" name=\"interfaces\"/>\n" \
	69	" </signal>\n" \
	70	" </interface>\n"
	71
	72	int introspect_begin(BusIntrospect *i, bool trusted) {
	73	FILE *f;
	74
	75	assert(i);
	76
	77	*i = (BusIntrospect) {
	78	.trusted = trusted,
	79	};
	80
	81	f = memstream_init(&i->m);
	82	if (!f)
	83	return -ENOMEM;
	84
	85	fputs(BUS_INTROSPECT_DOCTYPE
	86	"<node>\n", f);
	87
	88	return 0;
	89	}
	90
	91	int introspect_write_default_interfaces(BusIntrospect *i, bool object_manager) {
	92	assert(i);
	93	assert(i->m.f);
	94
	95	fputs(BUS_INTROSPECT_INTERFACE_PEER
	96	BUS_INTROSPECT_INTERFACE_INTROSPECTABLE
	97	BUS_INTROSPECT_INTERFACE_PROPERTIES, i->m.f);
	98
	99	if (object_manager)
	100	fputs(BUS_INTROSPECT_INTERFACE_OBJECT_MANAGER, i->m.f);
	101
	102	return 0;
	103	}
	104
	105	static int set_interface_name(BusIntrospect i, const char interface_name) {
	106	assert(i);
	107	assert(i->m.f);
	108
	109	if (streq_ptr(i->interface_name, interface_name))
	110	return 0;
	111
	112	if (i->interface_name)
	113	fputs(" </interface>\n", i->m.f);
	114
	115	if (interface_name)
	116	fprintf(i->m.f, " <interface name=\"%s\">\n", interface_name);
	117
	118	return free_and_strdup(&i->interface_name, interface_name);
	119	}
	120
	121	int introspect_write_child_nodes(BusIntrospect i, OrderedSet s, const char *prefix) {
	122	char *node;
	123
	124	assert(i);
	125	assert(i->m.f);
	126	assert(prefix);
	127
	128	assert_se(set_interface_name(i, NULL) >= 0);
	129
	130	while ((node = ordered_set_steal_first(s))) {
	131	const char *e;
	132
	133	e = object_path_startswith(node, prefix);
	134	if (e && e[0])
	135	fprintf(i->m.f, " <node name=\"%s\"/>\n", e);
	136
	137	free(node);
	138	}
	139
	140	return 0;
	141	}
	142
	143	static void introspect_write_flags(BusIntrospect *i, int type, uint64_t flags) {
	144	assert(i);
	145	assert(i->m.f);
	146
	147	if (flags & SD_BUS_VTABLE_DEPRECATED)
	148	fputs(" <annotation name=\"org.freedesktop.DBus.Deprecated\" value=\"true\"/>\n", i->m.f);
	149
	150	if (type == _SD_BUS_VTABLE_METHOD && (flags & SD_BUS_VTABLE_METHOD_NO_REPLY))
	151	fputs(" <annotation name=\"org.freedesktop.DBus.Method.NoReply\" value=\"true\"/>\n", i->m.f);
	152
	153	if (IN_SET(type, _SD_BUS_VTABLE_PROPERTY, _SD_BUS_VTABLE_WRITABLE_PROPERTY)) {
	154	if (flags & SD_BUS_VTABLE_PROPERTY_EXPLICIT)
	155	fputs(" <annotation name=\"org.freedesktop.systemd1.Explicit\" value=\"true\"/>\n", i->m.f);
	156
	157	if (flags & SD_BUS_VTABLE_PROPERTY_CONST)
	158	fputs(" <annotation name=\"org.freedesktop.DBus.Property.EmitsChangedSignal\" value=\"const\"/>\n", i->m.f);
	159	else if (flags & SD_BUS_VTABLE_PROPERTY_EMITS_INVALIDATION)
	160	fputs(" <annotation name=\"org.freedesktop.DBus.Property.EmitsChangedSignal\" value=\"invalidates\"/>\n", i->m.f);
	161	else if (!(flags & SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE))
	162	fputs(" <annotation name=\"org.freedesktop.DBus.Property.EmitsChangedSignal\" value=\"false\"/>\n", i->m.f);
	163	}
	164
	165	if (!i->trusted &&
	166	IN_SET(type, _SD_BUS_VTABLE_METHOD, _SD_BUS_VTABLE_WRITABLE_PROPERTY) &&
	167	!(flags & SD_BUS_VTABLE_UNPRIVILEGED))
	168	fputs(" <annotation name=\"org.freedesktop.systemd1.Privileged\" value=\"true\"/>\n", i->m.f);
	169	}
	170
	171	/* Note that "names" is both an input and an output parameter. It initially points to the first argument name in a
	172	NULL-separated list of strings, and is then advanced with each argument, and the resulting pointer is returned. */
	173	static int introspect_write_arguments(BusIntrospect i, const char signature, const char *names, const char direction) {
	174	int r;
	175
	176	assert(i);
	177	assert(i->m.f);
	178
	179	for (;;) {
	180	size_t l;
	181
	182	if (!*signature)
	183	return 0;
	184
	185	r = signature_element_length(signature, &l);
	186	if (r < 0)
	187	return r;
	188
	189	fprintf(i->m.f, " <arg type=\"%.*s\"", (int) l, signature);
	190
	191	if (**names != '\0') {
	192	fprintf(i->m.f, " name=\"%s\"", *names);
	193	names += strlen(names) + 1;
	194	}
	195
	196	if (direction)
	197	fprintf(i->m.f, " direction=\"%s\"/>\n", direction);
	198	else
	199	fputs("/>\n", i->m.f);
	200
	201	signature += l;
	202	}
	203	}
	204
	205	int introspect_write_interface(
	206	BusIntrospect *i,
	207	const char *interface_name,
	208	const sd_bus_vtable *v) {
	209
	210	const sd_bus_vtable *vtable = ASSERT_PTR(v);
	211	const char *names = "";
	212	int r;
	213
	214	assert(i);
	215	assert(i->m.f);
	216	assert(interface_name);
	217
	218	r = set_interface_name(i, interface_name);
	219	if (r < 0)
	220	return r;
	221
	222	for (; v->type != _SD_BUS_VTABLE_END; v = bus_vtable_next(vtable, v)) {
	223
	224	/* Ignore methods, signals and properties that are
	225	* marked "hidden", but do show the interface
	226	* itself */
	227
	228	if (v->type != _SD_BUS_VTABLE_START && (v->flags & SD_BUS_VTABLE_HIDDEN))
	229	continue;
	230
	231	switch (v->type) {
	232
	233	case _SD_BUS_VTABLE_START:
	234	if (v->flags & SD_BUS_VTABLE_DEPRECATED)
	235	fputs(" <annotation name=\"org.freedesktop.DBus.Deprecated\" value=\"true\"/>\n", i->m.f);
	236	break;
	237
	238	case _SD_BUS_VTABLE_METHOD:
	239	fprintf(i->m.f, " <method name=\"%s\">\n", v->x.method.member);
	240	if (bus_vtable_has_names(vtable))
	241	names = strempty(v->x.method.names);
	242	introspect_write_arguments(i, strempty(v->x.method.signature), &names, "in");
	243	introspect_write_arguments(i, strempty(v->x.method.result), &names, "out");
	244	introspect_write_flags(i, v->type, v->flags);
	245	fputs(" </method>\n", i->m.f);
	246	break;
	247
	248	case _SD_BUS_VTABLE_PROPERTY:
	249	case _SD_BUS_VTABLE_WRITABLE_PROPERTY:
	250	fprintf(i->m.f, " <property name=\"%s\" type=\"%s\" access=\"%s\">\n",
	251	v->x.property.member,
	252	v->x.property.signature,
	253	v->type == _SD_BUS_VTABLE_WRITABLE_PROPERTY ? "readwrite" : "read");
	254	introspect_write_flags(i, v->type, v->flags);
	255	fputs(" </property>\n", i->m.f);
	256	break;
	257
	258	case _SD_BUS_VTABLE_SIGNAL:
	259	fprintf(i->m.f, " <signal name=\"%s\">\n", v->x.signal.member);
	260	if (bus_vtable_has_names(vtable))
	261	names = strempty(v->x.signal.names);
	262	introspect_write_arguments(i, strempty(v->x.signal.signature), &names, NULL);
	263	introspect_write_flags(i, v->type, v->flags);
	264	fputs(" </signal>\n", i->m.f);
	265	break;
	266	}
	267
	268	}
	269
	270	return 0;
	271	}
	272
	273	int introspect_finish(BusIntrospect i, char *ret) {
	274	assert(i);
	275	assert(i->m.f);
	276
	277	assert_se(set_interface_name(i, NULL) >= 0);
	278
	279	fputs("</node>\n", i->m.f);
	280
	281	return memstream_finalize(&i->m, ret, NULL);
	282	}
	283
	284	void introspect_done(BusIntrospect *i) {
	285	assert(i);
	286
	287	/* Normally introspect_finish() does all the work, this is just a backup for error paths */
	288
	289	memstream_done(&i->m);
	290	free(i->interface_name);
	291	}