resolved-mdns.c revision bc7702b098b63031767174206f5df14a8ccb45cf
/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
/***
This file is part of systemd.
Copyright 2015 Daniel Mack
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <resolv.h>
#include "fd-util.h"
#include "resolved-manager.h"
#include "resolved-mdns.h"
void manager_mdns_stop(Manager *m) {
assert(m);
}
int manager_mdns_start(Manager *m) {
int r;
assert(m);
if (m->mdns_support == SUPPORT_NO)
return 0;
r = manager_mdns_ipv4_fd(m);
if (r == -EADDRINUSE)
goto eaddrinuse;
if (r < 0)
return r;
if (socket_ipv6_is_supported()) {
r = manager_mdns_ipv6_fd(m);
if (r == -EADDRINUSE)
goto eaddrinuse;
if (r < 0)
return r;
}
return 0;
log_warning("There appears to be another mDNS responder running. Turning off mDNS support.");
m->mdns_support = SUPPORT_NO;
return 0;
}
/* TODO */
return 0;
}
int manager_mdns_ipv4_fd(Manager *m) {
union sockaddr_union sa = {
};
int r;
assert(m);
if (m->mdns_ipv4_fd >= 0)
return m->mdns_ipv4_fd;
if (m->mdns_ipv4_fd < 0)
return -errno;
if (r < 0) {
r = -errno;
goto fail;
}
if (r < 0) {
r = -errno;
goto fail;
}
if (r < 0) {
r = -errno;
goto fail;
}
if (r < 0) {
r = -errno;
goto fail;
}
if (r < 0) {
r = -errno;
goto fail;
}
if (r < 0) {
r = -errno;
goto fail;
}
/* Disable Don't-Fragment bit in the IP header */
if (r < 0) {
r = -errno;
goto fail;
}
if (r < 0) {
r = -errno;
goto fail;
}
r = sd_event_add_io(m->event, &m->mdns_ipv4_event_source, m->mdns_ipv4_fd, EPOLLIN, on_mdns_packet, m);
if (r < 0)
goto fail;
return m->mdns_ipv4_fd;
fail:
return r;
}
int manager_mdns_ipv6_fd(Manager *m) {
union sockaddr_union sa = {
};
int r;
assert(m);
if (m->mdns_ipv6_fd >= 0)
return m->mdns_ipv6_fd;
if (m->mdns_ipv6_fd < 0)
return -errno;
if (r < 0) {
r = -errno;
goto fail;
}
/* RFC 4795, section 2.5 recommends setting the TTL of UDP packets to 255. */
if (r < 0) {
r = -errno;
goto fail;
}
if (r < 0) {
r = -errno;
goto fail;
}
if (r < 0) {
r = -errno;
goto fail;
}
if (r < 0) {
r = -errno;
goto fail;
}
if (r < 0) {
r = -errno;
goto fail;
}
if (r < 0) {
r = -errno;
goto fail;
}
if (r < 0) {
r = -errno;
goto fail;
}
r = sd_event_add_io(m->event, &m->mdns_ipv6_event_source, m->mdns_ipv6_fd, EPOLLIN, on_mdns_packet, m);
if (r < 0) {
r = -errno;
goto fail;
}
return m->mdns_ipv6_fd;
fail:
return r;
}