Adding upstream version 255.4.upstream/255.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 362 insertions, 0 deletions

diff --git a/src/resolve/resolved-dnssd.c b/src/resolve/resolved-dnssd.c
new file mode 100644
index 0000000..994771e
--- /dev/null
+++ b/src/resolve/resolved-dnssd.c
@@ -0,0 +1,362 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include "conf-files.h"
+#include "conf-parser.h"
+#include "constants.h"
+#include "resolved-dnssd.h"
+#include "resolved-dns-rr.h"
+#include "resolved-manager.h"
+#include "resolved-conf.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->txts);
+
+        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(
+                        STRV_MAKE_CONST(filename), DNSSD_SERVICE_DIRS, dropin_dirname, /* root = */ NULL,
+                        "Service\0",
+                        config_item_perf_lookup, resolved_dnssd_gperf_lookup,
+                        CONFIG_PARSE_WARN,
+                        service,
+                        NULL,
+                        NULL);
+        if (r < 0)
+                return r;
+
+        if (!service->name_template)
+                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+                                       "%s doesn't define service instance name",
+                                       service->name);
+
+        if (!service->type)
+                return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
+                                       "%s doesn't define service type",
+                                       service->name);
+
+        if (!service->txt_data_items) {
+                txt_data = new0(DnssdTxtData, 1);
+                if (!txt_data)
+                        return log_oom();
+
+                r = dns_txt_item_new_empty(&txt_data->txts);
+                if (r < 0)
+                        return r;
+
+                LIST_PREPEND(items, service->txt_data_items, txt_data);
+                TAKE_PTR(txt_data);
+        }
+
+        r = hashmap_ensure_put(&manager->dnssd_services, &string_hash_ops, service->name, service);
+        if (r < 0)
+                return r;
+
+        service->manager = manager;
+
+        r = dnssd_update_rrs(service);
+        if (r < 0)
+                return r;
+
+        TAKE_PTR(service);
+
+        return 0;
+}
+
+static int specifier_dnssd_hostname(char specifier, const void *data, const char *root, const void *userdata, char **ret) {
+        const Manager *m = ASSERT_PTR(userdata);
+        char *n;
+
+        assert(m->llmnr_hostname);
+
+        n = strdup(m->llmnr_hostname);
+        if (!n)
+                return -ENOMEM;
+
+        *ret = n;
+        return 0;
+}
+
+int dnssd_render_instance_name(Manager *m, DnssdService *s, char **ret) {
+        static const Specifier specifier_table[] = {
+                { 'a', specifier_architecture,   NULL },
+                { 'b', specifier_boot_id,        NULL },
+                { 'B', specifier_os_build_id,    NULL },
+                { 'H', specifier_dnssd_hostname, NULL },
+                { 'm', specifier_machine_id,     NULL },
+                { 'o', specifier_os_id,          NULL },
+                { 'v', specifier_kernel_release, NULL },
+                { 'w', specifier_os_version_id,  NULL },
+                { 'W', specifier_os_variant_id,  NULL },
+                {}
+        };
+        _cleanup_free_ char *name = NULL;
+        int r;
+
+        assert(m);
+        assert(s);
+        assert(s->name_template);
+
+        r = specifier_printf(s->name_template, DNS_LABEL_MAX, specifier_table, NULL, m, &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);
+
+        if (ret)
+                *ret = TAKE_PTR(name);
+
+        return 0;
+}
+
+int dnssd_load(Manager *manager) {
+        _cleanup_strv_free_ char **files = NULL;
+        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, *service_name = NULL, *full_name = NULL;
+        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->manager, 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->txts);
+                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;
+}
+
+int dnssd_signal_conflict(Manager *manager, const char *name) {
+        DnssdService *s;
+        int r;
+
+        if (sd_bus_is_ready(manager->bus) <= 0)
+                return 0;
+
+        HASHMAP_FOREACH(s, manager->dnssd_services) {
+                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)
+                                return log_error_errno(r, "Can't get D-BUS object path: %m");
+
+                        r = sd_bus_emit_signal(manager->bus,
+                                               path,
+                                               "org.freedesktop.resolve1.DnssdService",
+                                               "Conflicted",
+                                               NULL);
+                        if (r < 0)
+                                return log_error_errno(r, "Cannot emit signal: %m");
+
+                        break;
+                }
+        }
+
+        return 0;
+}