[thirdparty/systemd.git] / src / resolve / resolved-dnssd.c

/* SPDX-License-Identifier: LGPL-2.1+ */

#include "conf-files.h"
#include "conf-parser.h"
#include "def.h"
#include "resolved-dnssd.h"
#include "resolved-dns-rr.h"
#include "resolved-manager.h"
#include "specifier.h"
#include "strv.h"

#define DNSSD_SERVICE_DIRS ((const char* const*) CONF_PATHS_STRV("systemd/dnssd"))

DnssdTxtData *dnssd_txtdata_free(DnssdTxtData *txt_data) {
        if (!txt_data)
                return NULL;

        dns_resource_record_unref(txt_data->rr);
        dns_txt_item_free_all(txt_data->txt);

        return mfree(txt_data);
}

DnssdTxtData *dnssd_txtdata_free_all(DnssdTxtData *txt_data) {
        DnssdTxtData *next;

        if (!txt_data)
                return NULL;

        next = txt_data->items_next;

        dnssd_txtdata_free(txt_data);

        return dnssd_txtdata_free_all(next);
}

DnssdService *dnssd_service_free(DnssdService *service) {
        if (!service)
                return NULL;

        if (service->manager)
                hashmap_remove(service->manager->dnssd_services, service->name);

        dns_resource_record_unref(service->ptr_rr);
        dns_resource_record_unref(service->srv_rr);

        dnssd_txtdata_free_all(service->txt_data_items);

        free(service->filename);
        free(service->name);
        free(service->type);
        free(service->name_template);

        return mfree(service);
}

static int dnssd_service_load(Manager *manager, const char *filename) {
        _cleanup_(dnssd_service_freep) DnssdService *service = NULL;
        _cleanup_(dnssd_txtdata_freep) DnssdTxtData *txt_data = NULL;
        char *d;
        const char *dropin_dirname;
        int r;

        assert(manager);
        assert(filename);

        service = new0(DnssdService, 1);
        if (!service)
                return log_oom();

        service->filename = strdup(filename);
        if (!service->filename)
                return log_oom();

        service->name = strdup(basename(filename));
        if (!service->name)
                return log_oom();

        d = endswith(service->name, ".dnssd");
        if (!d)
                return -EINVAL;

        assert(streq(d, ".dnssd"));

        *d = '\0';

        dropin_dirname = strjoina(service->name, ".dnssd.d");

        r = config_parse_many(
                        filename, DNSSD_SERVICE_DIRS, dropin_dirname,
                        "Service\0",
                        config_item_perf_lookup, resolved_dnssd_gperf_lookup,
                        CONFIG_PARSE_WARN,
                        service,
                        NULL);
        if (r < 0)
                return r;

        if (!service->name_template) {
                log_error("%s doesn't define service instance name", service->name);
                return -EINVAL;
        }

        if (!service->type) {
                log_error("%s doesn't define service type", service->name);
                return -EINVAL;
        }

        if (LIST_IS_EMPTY(service->txt_data_items)) {
                txt_data = new0(DnssdTxtData, 1);
                if (!txt_data)
                        return log_oom();

                r = dns_txt_item_new_empty(&txt_data->txt);
                if (r < 0)
                        return r;

                LIST_PREPEND(items, service->txt_data_items, txt_data);
                txt_data = NULL;
        }

        r = hashmap_ensure_allocated(&manager->dnssd_services, &string_hash_ops);
        if (r < 0)
                return r;

        r = hashmap_put(manager->dnssd_services, service->name, service);
        if (r < 0)
                return r;

        service->manager = manager;

        r = dnssd_update_rrs(service);
        if (r < 0)
                return r;

        service = NULL;

        return 0;
}

static int specifier_dnssd_host_name(char specifier, const void *data, const void *userdata, char **ret) {
        DnssdService *s  = (DnssdService *) userdata;
        char *n;

        assert(s);
        assert(s->manager);
        assert(s->manager->llmnr_hostname);

        n = strdup(s->manager->llmnr_hostname);
        if (!n)
                return -ENOMEM;

        *ret = n;
        return 0;
}

int dnssd_render_instance_name(DnssdService *s, char **ret_name) {
        static const Specifier specifier_table[] = {
                { 'm', specifier_machine_id,      NULL },
                { 'b', specifier_boot_id,         NULL },
                { 'H', specifier_dnssd_host_name, NULL },
                { 'v', specifier_kernel_release,  NULL },
                { 'a', specifier_architecture,    NULL },
                { 'o', specifier_os_id,           NULL },
                { 'w', specifier_os_version_id,   NULL },
                { 'B', specifier_os_build_id,     NULL },
                { 'W', specifier_os_variant_id,   NULL },
                {}
        };
        _cleanup_free_ char *name = NULL;
        int r;

        assert(s);
        assert(s->name_template);

        r = specifier_printf(s->name_template, specifier_table, s, &name);
        if (r < 0)
                return log_debug_errno(r, "Failed to replace specifiers: %m");

        if (!dns_service_name_is_valid(name))
                return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),
                                       "Service instance name '%s' is invalid.",
                                       name);

        *ret_name = TAKE_PTR(name);

        return 0;
}

int dnssd_load(Manager *manager) {
        _cleanup_strv_free_ char **files = NULL;
        char **f;
        int r;

        assert(manager);

        if (manager->mdns_support != RESOLVE_SUPPORT_YES)
                return 0;

        r = conf_files_list_strv(&files, ".dnssd", NULL, 0, DNSSD_SERVICE_DIRS);
        if (r < 0)
                return log_error_errno(r, "Failed to enumerate .dnssd files: %m");

        STRV_FOREACH_BACKWARDS(f, files) {
                r = dnssd_service_load(manager, *f);
                if (r < 0)
                        log_warning_errno(r, "Failed to load '%s': %m", *f);;
        }

        return 0;
}

int dnssd_update_rrs(DnssdService *s) {
        _cleanup_free_ char *n = NULL;
        _cleanup_free_ char *service_name = NULL;
        _cleanup_free_ char *full_name = NULL;
        DnssdTxtData *txt_data;
        int r;

        assert(s);
        assert(s->txt_data_items);
        assert(s->manager);

        s->ptr_rr = dns_resource_record_unref(s->ptr_rr);
        s->srv_rr = dns_resource_record_unref(s->srv_rr);
        LIST_FOREACH(items, txt_data, s->txt_data_items)
                txt_data->rr = dns_resource_record_unref(txt_data->rr);

        r = dnssd_render_instance_name(s, &n);
        if (r < 0)
                return r;

        r = dns_name_concat(s->type, "local", 0, &service_name);
        if (r < 0)
                return r;
        r = dns_name_concat(n, service_name, 0, &full_name);
        if (r < 0)
                return r;

        LIST_FOREACH(items, txt_data, s->txt_data_items) {
                txt_data->rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_TXT,
                                                            full_name);
                if (!txt_data->rr)
                        goto oom;

                txt_data->rr->ttl = MDNS_DEFAULT_TTL;
                txt_data->rr->txt.items = dns_txt_item_copy(txt_data->txt);
                if (!txt_data->rr->txt.items)
                        goto oom;
        }

        s->ptr_rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_PTR,
                                                 service_name);
        if (!s->ptr_rr)
                goto oom;

        s->ptr_rr->ttl = MDNS_DEFAULT_TTL;
        s->ptr_rr->ptr.name = strdup(full_name);
        if (!s->ptr_rr->ptr.name)
                goto oom;

        s->srv_rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_SRV,
                                                 full_name);
        if (!s->srv_rr)
                goto oom;

        s->srv_rr->ttl = MDNS_DEFAULT_TTL;
        s->srv_rr->srv.priority = s->priority;
        s->srv_rr->srv.weight = s->weight;
        s->srv_rr->srv.port = s->port;
        s->srv_rr->srv.name = strdup(s->manager->mdns_hostname);
        if (!s->srv_rr->srv.name)
                goto oom;

        return 0;

oom:
        LIST_FOREACH(items, txt_data, s->txt_data_items)
                txt_data->rr = dns_resource_record_unref(txt_data->rr);
        s->ptr_rr = dns_resource_record_unref(s->ptr_rr);
        s->srv_rr = dns_resource_record_unref(s->srv_rr);
        return -ENOMEM;
}

int dnssd_txt_item_new_from_string(const char *key, const char *value, DnsTxtItem **ret_item) {
        size_t length;
        DnsTxtItem *i;

        length = strlen(key);

        if (!isempty(value))
                length += strlen(value) + 1; /* length of value plus '=' */

        i = malloc0(offsetof(DnsTxtItem, data) + length + 1); /* for safety reasons we add an extra NUL byte */
        if (!i)
                return -ENOMEM;

        memcpy(i->data, key, strlen(key));
        if (!isempty(value)) {
                memcpy(i->data + strlen(key), "=", 1);
                memcpy(i->data + strlen(key) + 1, value, strlen(value));
        }
        i->length = length;

        *ret_item = TAKE_PTR(i);

        return 0;
}

int dnssd_txt_item_new_from_data(const char *key, const void *data, const size_t size, DnsTxtItem **ret_item) {
        size_t length;
        DnsTxtItem *i;

        length = strlen(key);

        if (size > 0)
                length += size + 1; /* size of date plus '=' */

        i = malloc0(offsetof(DnsTxtItem, data) + length + 1); /* for safety reasons we add an extra NUL byte */
        if (!i)
                return -ENOMEM;

        memcpy(i->data, key, strlen(key));
        if (size > 0) {
                memcpy(i->data + strlen(key), "=", 1);
                memcpy(i->data + strlen(key) + 1, data, size);
        }
        i->length = length;

        *ret_item = TAKE_PTR(i);

        return 0;
}

void dnssd_signal_conflict(Manager *manager, const char *name) {
        Iterator i;
        DnssdService *s;
        int r;

        HASHMAP_FOREACH(s, manager->dnssd_services, i) {
                if (s->withdrawn)
                        continue;

                if (dns_name_equal(dns_resource_key_name(s->srv_rr->key), name)) {
                        _cleanup_free_ char *path = NULL;

                        s->withdrawn = true;

                        r = sd_bus_path_encode("/org/freedesktop/resolve1/dnssd", s->name, &path);
                        if (r < 0) {
                                log_error_errno(r, "Can't get D-BUS object path: %m");
                                return;
                        }

                        r = sd_bus_emit_signal(manager->bus,
                                               path,
                                               "org.freedesktop.resolve1.DnssdService",
                                               "Conflicted",
                                               NULL);
                        if (r < 0) {
                                log_error_errno(r, "Cannot emit signal: %m");
                                return;
                        }

                        break;
                }
        }
}
Commit	Line	Data
514fbdd7	1	/* SPDX-License-Identifier: LGPL-2.1+ */
6501dd31 DR	2
	3	#include "conf-files.h"
	4	#include "conf-parser.h"
eb5f4dde	5	#include "def.h"
6501dd31 DR	6	#include "resolved-dnssd.h"
	7	#include "resolved-dns-rr.h"
	8	#include "resolved-manager.h"
	9	#include "specifier.h"
	10	#include "strv.h"
	11
eb5f4dde	12	#define DNSSD_SERVICE_DIRS ((const char* const*) CONF_PATHS_STRV("systemd/dnssd"))
6501dd31	13
400f54fb DR	14	DnssdTxtData dnssd_txtdata_free(DnssdTxtData txt_data) {
	15	if (!txt_data)
	16	return NULL;
	17
	18	dns_resource_record_unref(txt_data->rr);
	19	dns_txt_item_free_all(txt_data->txt);
	20
	21	return mfree(txt_data);
	22	}
	23
	24	DnssdTxtData dnssd_txtdata_free_all(DnssdTxtData txt_data) {
	25	DnssdTxtData *next;
	26
	27	if (!txt_data)
	28	return NULL;
	29
	30	next = txt_data->items_next;
	31
	32	dnssd_txtdata_free(txt_data);
	33
	34	return dnssd_txtdata_free_all(next);
	35	}
	36
6501dd31 DR	37	DnssdService dnssd_service_free(DnssdService service) {
	38	if (!service)
	39	return NULL;
	40
	41	if (service->manager)
	42	hashmap_remove(service->manager->dnssd_services, service->name);
	43
	44	dns_resource_record_unref(service->ptr_rr);
	45	dns_resource_record_unref(service->srv_rr);
400f54fb DR	46
400f54fb DR	47	dnssd_txtdata_free_all(service->txt_data_items);
6501dd31 DR	48
	49	free(service->filename);
	50	free(service->name);
	51	free(service->type);
	52	free(service->name_template);
6501dd31 DR	53
	54	return mfree(service);
	55	}
	56
	57	static int dnssd_service_load(Manager manager, const char filename) {
	58	_cleanup_(dnssd_service_freep) DnssdService *service = NULL;
400f54fb	59	_cleanup_(dnssd_txtdata_freep) DnssdTxtData *txt_data = NULL;
6501dd31 DR	60	char *d;
	61	const char *dropin_dirname;
	62	int r;
	63
	64	assert(manager);
	65	assert(filename);
	66
	67	service = new0(DnssdService, 1);
	68	if (!service)
	69	return log_oom();
	70
	71	service->filename = strdup(filename);
	72	if (!service->filename)
	73	return log_oom();
	74
	75	service->name = strdup(basename(filename));
	76	if (!service->name)
	77	return log_oom();
	78
	79	d = endswith(service->name, ".dnssd");
	80	if (!d)
	81	return -EINVAL;
	82
	83	assert(streq(d, ".dnssd"));
	84
	85	*d = '\0';
	86
	87	dropin_dirname = strjoina(service->name, ".dnssd.d");
	88
4f9ff96a LP	89	r = config_parse_many(
	90	filename, DNSSD_SERVICE_DIRS, dropin_dirname,
	91	"Service\0",
	92	config_item_perf_lookup, resolved_dnssd_gperf_lookup,
	93	CONFIG_PARSE_WARN,
	94	service,
	95	NULL);
6501dd31 DR	96	if (r < 0)
	97	return r;
	98
	99	if (!service->name_template) {
	100	log_error("%s doesn't define service instance name", service->name);
	101	return -EINVAL;
	102	}
	103
	104	if (!service->type) {
	105	log_error("%s doesn't define service type", service->name);
	106	return -EINVAL;
	107	}
	108
400f54fb DR	109	if (LIST_IS_EMPTY(service->txt_data_items)) {
	110	txt_data = new0(DnssdTxtData, 1);
	111	if (!txt_data)
	112	return log_oom();
	113
	114	r = dns_txt_item_new_empty(&txt_data->txt);
6501dd31 DR	115	if (r < 0)
6501dd31 DR	116	return r;
400f54fb DR	117
	118	LIST_PREPEND(items, service->txt_data_items, txt_data);
	119	txt_data = NULL;
6501dd31 DR	120	}
	121
	122	r = hashmap_ensure_allocated(&manager->dnssd_services, &string_hash_ops);
	123	if (r < 0)
	124	return r;
	125
	126	r = hashmap_put(manager->dnssd_services, service->name, service);
	127	if (r < 0)
	128	return r;
	129
	130	service->manager = manager;
	131
6db6a464 DR	132	r = dnssd_update_rrs(service);
	133	if (r < 0)
	134	return r;
	135
6501dd31 DR	136	service = NULL;
	137
	138	return 0;
	139	}
	140
303ee601	141	static int specifier_dnssd_host_name(char specifier, const void data, const void userdata, char **ret) {
6501dd31 DR	142	DnssdService s = (DnssdService ) userdata;
	143	char *n;
	144
	145	assert(s);
	146	assert(s->manager);
	147	assert(s->manager->llmnr_hostname);
	148
	149	n = strdup(s->manager->llmnr_hostname);
	150	if (!n)
	151	return -ENOMEM;
	152
	153	*ret = n;
	154	return 0;
	155	}
	156
	157	int dnssd_render_instance_name(DnssdService s, char *ret_name) {
	158	static const Specifier specifier_table[] = {
268f5a54	159	{ 'm', specifier_machine_id, NULL },
6501dd31 DR	160	{ 'b', specifier_boot_id, NULL },
6501dd31 DR	161	{ 'H', specifier_dnssd_host_name, NULL },
6501dd31	162	{ 'v', specifier_kernel_release, NULL },
268f5a54 LP	163	{ 'a', specifier_architecture, NULL },
	164	{ 'o', specifier_os_id, NULL },
	165	{ 'w', specifier_os_version_id, NULL },
	166	{ 'B', specifier_os_build_id, NULL },
	167	{ 'W', specifier_os_variant_id, NULL },
6501dd31 DR	168	{}
	169	};
	170	_cleanup_free_ char *name = NULL;
	171	int r;
	172
	173	assert(s);
	174	assert(s->name_template);
	175
	176	r = specifier_printf(s->name_template, specifier_table, s, &name);
	177	if (r < 0)
	178	return log_debug_errno(r, "Failed to replace specifiers: %m");
	179
baaa35ad ZJS	180	if (!dns_service_name_is_valid(name))
	181	return log_debug_errno(SYNTHETIC_ERRNO(EINVAL),
	182	"Service instance name '%s' is invalid.",
	183	name);
6501dd31	184
ae2a15bc	185	*ret_name = TAKE_PTR(name);
6501dd31 DR	186
	187	return 0;
	188	}
	189
	190	int dnssd_load(Manager *manager) {
	191	_cleanup_strv_free_ char **files = NULL;
	192	char **f;
	193	int r;
	194
	195	assert(manager);
	196
	197	if (manager->mdns_support != RESOLVE_SUPPORT_YES)
	198	return 0;
	199
eb5f4dde	200	r = conf_files_list_strv(&files, ".dnssd", NULL, 0, DNSSD_SERVICE_DIRS);
6501dd31 DR	201	if (r < 0)
	202	return log_error_errno(r, "Failed to enumerate .dnssd files: %m");
	203
	204	STRV_FOREACH_BACKWARDS(f, files) {
	205	r = dnssd_service_load(manager, *f);
	206	if (r < 0)
	207	log_warning_errno(r, "Failed to load '%s': %m", *f);;
	208	}
	209
	210	return 0;
	211	}
	212
6db6a464 DR	213	int dnssd_update_rrs(DnssdService *s) {
	214	_cleanup_free_ char *n = NULL;
	215	_cleanup_free_ char *service_name = NULL;
	216	_cleanup_free_ char *full_name = NULL;
400f54fb	217	DnssdTxtData *txt_data;
6db6a464 DR	218	int r;
	219
	220	assert(s);
400f54fb	221	assert(s->txt_data_items);
6db6a464 DR	222	assert(s->manager);
	223
	224	s->ptr_rr = dns_resource_record_unref(s->ptr_rr);
	225	s->srv_rr = dns_resource_record_unref(s->srv_rr);
400f54fb DR	226	LIST_FOREACH(items, txt_data, s->txt_data_items)
400f54fb DR	227	txt_data->rr = dns_resource_record_unref(txt_data->rr);
6db6a464 DR	228
	229	r = dnssd_render_instance_name(s, &n);
	230	if (r < 0)
	231	return r;
	232
7470cc4c	233	r = dns_name_concat(s->type, "local", 0, &service_name);
6db6a464 DR	234	if (r < 0)
6db6a464 DR	235	return r;
7470cc4c	236	r = dns_name_concat(n, service_name, 0, &full_name);
6db6a464 DR	237	if (r < 0)
	238	return r;
	239
400f54fb DR	240	LIST_FOREACH(items, txt_data, s->txt_data_items) {
	241	txt_data->rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_TXT,
	242	full_name);
	243	if (!txt_data->rr)
	244	goto oom;
6db6a464	245
400f54fb DR	246	txt_data->rr->ttl = MDNS_DEFAULT_TTL;
	247	txt_data->rr->txt.items = dns_txt_item_copy(txt_data->txt);
	248	if (!txt_data->rr->txt.items)
	249	goto oom;
	250	}
6db6a464 DR	251
	252	s->ptr_rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_PTR,
	253	service_name);
	254	if (!s->ptr_rr)
	255	goto oom;
	256
	257	s->ptr_rr->ttl = MDNS_DEFAULT_TTL;
	258	s->ptr_rr->ptr.name = strdup(full_name);
	259	if (!s->ptr_rr->ptr.name)
	260	goto oom;
	261
	262	s->srv_rr = dns_resource_record_new_full(DNS_CLASS_IN, DNS_TYPE_SRV,
	263	full_name);
	264	if (!s->srv_rr)
	265	goto oom;
	266
	267	s->srv_rr->ttl = MDNS_DEFAULT_TTL;
	268	s->srv_rr->srv.priority = s->priority;
	269	s->srv_rr->srv.weight = s->weight;
	270	s->srv_rr->srv.port = s->port;
	271	s->srv_rr->srv.name = strdup(s->manager->mdns_hostname);
	272	if (!s->srv_rr->srv.name)
	273	goto oom;
	274
	275	return 0;
	276
	277	oom:
400f54fb DR	278	LIST_FOREACH(items, txt_data, s->txt_data_items)
400f54fb DR	279	txt_data->rr = dns_resource_record_unref(txt_data->rr);
6db6a464 DR	280	s->ptr_rr = dns_resource_record_unref(s->ptr_rr);
	281	s->srv_rr = dns_resource_record_unref(s->srv_rr);
	282	return -ENOMEM;
	283	}
	284
6501dd31 DR	285	int dnssd_txt_item_new_from_string(const char key, const char value, DnsTxtItem **ret_item) {
	286	size_t length;
	287	DnsTxtItem *i;
	288
	289	length = strlen(key);
	290
	291	if (!isempty(value))
	292	length += strlen(value) + 1; /* length of value plus '=' */
	293
	294	i = malloc0(offsetof(DnsTxtItem, data) + length + 1); /* for safety reasons we add an extra NUL byte */
	295	if (!i)
	296	return -ENOMEM;
	297
	298	memcpy(i->data, key, strlen(key));
	299	if (!isempty(value)) {
	300	memcpy(i->data + strlen(key), "=", 1);
	301	memcpy(i->data + strlen(key) + 1, value, strlen(value));
	302	}
	303	i->length = length;
	304
ae2a15bc	305	*ret_item = TAKE_PTR(i);
6501dd31 DR	306
	307	return 0;
	308	}
	309
	310	int dnssd_txt_item_new_from_data(const char key, const void data, const size_t size, DnsTxtItem **ret_item) {
	311	size_t length;
	312	DnsTxtItem *i;
	313
	314	length = strlen(key);
	315
	316	if (size > 0)
	317	length += size + 1; /* size of date plus '=' */
	318
	319	i = malloc0(offsetof(DnsTxtItem, data) + length + 1); /* for safety reasons we add an extra NUL byte */
	320	if (!i)
	321	return -ENOMEM;
	322
	323	memcpy(i->data, key, strlen(key));
	324	if (size > 0) {
	325	memcpy(i->data + strlen(key), "=", 1);
	326	memcpy(i->data + strlen(key) + 1, data, size);
	327	}
	328	i->length = length;
	329
ae2a15bc	330	*ret_item = TAKE_PTR(i);
6501dd31 DR	331
	332	return 0;
	333	}
c3036641 DR	334
	335	void dnssd_signal_conflict(Manager manager, const char name) {
	336	Iterator i;
	337	DnssdService *s;
	338	int r;
	339
	340	HASHMAP_FOREACH(s, manager->dnssd_services, i) {
	341	if (s->withdrawn)
	342	continue;
	343
	344	if (dns_name_equal(dns_resource_key_name(s->srv_rr->key), name)) {
	345	_cleanup_free_ char *path = NULL;
	346
	347	s->withdrawn = true;
	348
	349	r = sd_bus_path_encode("/org/freedesktop/resolve1/dnssd", s->name, &path);
	350	if (r < 0) {
	351	log_error_errno(r, "Can't get D-BUS object path: %m");
	352	return;
	353	}
	354
	355	r = sd_bus_emit_signal(manager->bus,
	356	path,
	357	"org.freedesktop.resolve1.DnssdService",
	358	"Conflicted",
	359	NULL);
	360	if (r < 0) {
	361	log_error_errno(r, "Cannot emit signal: %m");
	362	return;
	363	}
	364
	365	break;
	366	}
	367	}
	368	}