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/*
* mDNS registration handler. This file is part of Shairport.
* Copyright (c) Paul Lietar 2013
* All rights reserved.
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use,
* copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*/
#include "mdns.h"
#include "common.h"
#include <ifaddrs.h>
#include <net/if.h>
#include <netinet/in.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <unistd.h>
#include "tinysvcmdns.h"
static struct mdnsd *svr = NULL;
static int mdns_tinysvcmdns_register(char *apname, int port) {
struct ifaddrs *ifalist;
struct ifaddrs *ifa;
svr = mdnsd_start();
if (svr == NULL) {
warn("tinysvcmdns: mdnsd_start() failed");
return -1;
}
// Thanks to Paul Lietar for this
// room for name + .local + NULL
char hostname[100 + 6];
gethostname(hostname, 99);
// according to POSIX, this may be truncated without a final NULL !
hostname[99] = 0;
// will not work if the hostname doesn't end in .local
char *hostend = hostname + strlen(hostname);
if ((strlen(hostname) < strlen(".local")) || (strcmp(hostend - 6, ".local") != 0)) {
strcat(hostname, ".local");
}
if (getifaddrs(&ifalist) < 0) {
warn("tinysvcmdns: getifaddrs() failed");
return -1;
}
ifa = ifalist;
// Look for an ipv4/ipv6 non-loopback interface to use as the main one.
for (ifa = ifalist; ifa != NULL; ifa = ifa->ifa_next) {
// only check for the named interface, if specified
if ((config.interface == NULL) || (strcmp(config.interface, ifa->ifa_name) == 0)) {
if (!(ifa->ifa_flags & IFF_LOOPBACK) && ifa->ifa_addr &&
ifa->ifa_addr->sa_family == AF_INET) {
uint32_t main_ip = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr;
mdnsd_set_hostname(svr, hostname, main_ip); // TTL should be 120 seconds
break;
} else if (!(ifa->ifa_flags & IFF_LOOPBACK) && ifa->ifa_addr &&
ifa->ifa_addr->sa_family == AF_INET6) {
struct in6_addr *addr = &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
mdnsd_set_hostname_v6(svr, hostname, addr); // TTL should be 120 seconds
break;
}
}
}
if (ifa == NULL) {
warn("tinysvcmdns: no non-loopback ipv4 or ipv6 interface found");
return -1;
}
// Skip the first one, it was already added by set_hostname
for (ifa = ifa->ifa_next; ifa != NULL; ifa = ifa->ifa_next) {
if (ifa->ifa_flags & IFF_LOOPBACK) // Skip loop-back interfaces
continue;
// only check for the named interface, if specified
if ((config.interface == NULL) || (strcmp(config.interface, ifa->ifa_name) == 0)) {
switch (ifa->ifa_addr->sa_family) {
case AF_INET: { // ipv4
uint32_t ip = ((struct sockaddr_in *)ifa->ifa_addr)->sin_addr.s_addr;
struct rr_entry *a_e =
rr_create_a(create_nlabel(hostname), ip); // TTL should be 120 seconds
mdnsd_add_rr(svr, a_e);
} break;
case AF_INET6: { // ipv6
struct in6_addr *addr = &((struct sockaddr_in6 *)ifa->ifa_addr)->sin6_addr;
struct rr_entry *aaaa_e =
rr_create_aaaa(create_nlabel(hostname), addr); // TTL should be 120 seconds
mdnsd_add_rr(svr, aaaa_e);
} break;
}
}
}
freeifaddrs(ifa);
char *txtwithoutmetadata[] = {MDNS_RECORD_WITHOUT_METADATA, NULL};
#ifdef CONFIG_METADATA
char *txtwithmetadata[] = {MDNS_RECORD_WITH_METADATA, NULL};
#endif
char **txt;
#ifdef CONFIG_METADATA
if (config.metadata_enabled)
txt = txtwithmetadata;
else
#endif
txt = txtwithoutmetadata;
if (config.regtype == NULL)
die("tinysvcmdns: regtype is null");
char *extendedregtype = malloc(strlen(config.regtype) + strlen(".local") + 1);
if (extendedregtype == NULL)
die("tinysvcmdns: could not allocated memory to request a Zeroconf service");
strcpy(extendedregtype, config.regtype);
strcat(extendedregtype, ".local");
struct mdns_service *svc =
mdnsd_register_svc(svr, apname, extendedregtype, port, NULL,
(const char **)txt); // TTL should be 75 minutes, i.e. 4500 seconds
mdns_service_destroy(svc);
free(extendedregtype);
return 0;
}
static void mdns_tinysvcmdns_unregister(void) {
if (svr) {
mdnsd_stop(svr);
svr = NULL;
}
}
mdns_backend mdns_tinysvcmdns = {.name = "tinysvcmdns",
.mdns_register = mdns_tinysvcmdns_register,
.mdns_unregister = mdns_tinysvcmdns_unregister};
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