// When a service is started or a browse is started with the Anonymous data, we allocate a new random
// number and based on that allocate a new NSEC3 resource record whose hash is a function of random number (salt) and
// the anonymous data.
//
// If we receive a packet with the NSEC3 option, we need to cache that along with the resource record so that we can
// check against the question to see whether it answers them or not. In that case, we pass the "rr" that we received.
mDNSexport AnonymousInfo *AllocateAnonInfo(const domainname *service, const mDNSu8 *data, int len, const ResourceRecord *rr)
{
AnonymousInfo *ai;
ai = (AnonymousInfo *)mDNSPlatformMemAllocate(sizeof(AnonymousInfo));
if (!ai)
{
return mDNSNULL;
}
mDNSPlatformMemZero(ai, sizeof(AnonymousInfo));
if (rr)
{
if (!CopyNSEC3ResourceRecord(ai, rr))
{
mDNSPlatformMemFree(ai);
return mDNSNULL;
}
return ai;
}
ai->salt = mDNSRandom(0xFFFFFFFF);
ai->AnonData = mDNSPlatformMemAllocate(len);
if (!ai->AnonData)
{
mDNSPlatformMemFree(ai);
return mDNSNULL;
}
ai->AnonDataLen = len;
mDNSPlatformMemCopy(ai->AnonData, data, len);
ai->nsec3RR = ConstructNSEC3Record(service, data, len, ai->salt);
if (!ai->nsec3RR)
{
mDNSPlatformMemFree(ai);
return mDNSNULL;
}
return ai;
}
static void DNSSD_API DNSServiceGetAddrInfoResponse(
DNSServiceRef inRef,
DNSServiceFlags inFlags,
uint32_t inInterfaceIndex,
DNSServiceErrorType inErrorCode,
const char * inFullName,
uint16_t inRRType,
uint16_t inRRClass,
uint16_t inRDLen,
const void * inRData,
uint32_t inTTL,
void * inContext )
{
mDNS_DirectOP_GetAddrInfo * x = (mDNS_DirectOP_GetAddrInfo*)inContext;
struct sockaddr_in sa4;
mDNSPlatformMemZero(&sa4, sizeof(sa4));
if (inErrorCode == kDNSServiceErr_NoError && inRRType == kDNSServiceType_A)
{
sa4.sin_family = AF_INET;
mDNSPlatformMemCopy(&sa4.sin_addr.s_addr, inRData, 4);
}
x->callback((DNSServiceRef)x, inFlags, inInterfaceIndex, inErrorCode, inFullName,
(const struct sockaddr *) &sa4, inTTL, x->context);
}
// mDNS core calls this routine when it needs to send a packet.
mDNSexport mStatus mDNSPlatformSendUDP(const mDNS *const m, const DNSMessage *const msg, const mDNSu8 *const end,
mDNSInterfaceID InterfaceID, mDNSIPPort srcPort, const mDNSAddr *dst, mDNSIPPort dstPort)
{
int err;
struct sockaddr_storage to;
PosixNetworkInterface * thisIntf;
assert(m != NULL);
assert(msg != NULL);
assert(end != NULL);
assert( (((char *) end) - ((char *) msg)) > 0 );
assert(InterfaceID != 0); // Can't send from zero source address
assert(srcPort.NotAnInteger != 0); // Nor from a zero source port
assert(dstPort.NotAnInteger != 0); // Nor from a zero source port
if (dst->type == mDNSAddrType_IPv4)
{
struct sockaddr_in *sin = (struct sockaddr_in*)&to;
#ifndef NOT_HAVE_SA_LEN
sin->sin_len = sizeof(*sin);
#endif
sin->sin_family = AF_INET;
sin->sin_port = dstPort.NotAnInteger;
sin->sin_addr.s_addr = dst->ip.v4.NotAnInteger;
}
#ifdef mDNSIPv6Support
else if (dst->type == mDNSAddrType_IPv6)
{
struct sockaddr_in6 *sin6 = (struct sockaddr_in6*)&to;
mDNSPlatformMemZero(sin6, sizeof(*sin6));
sin6->sin6_len = sizeof(*sin6);
sin6->sin6_family = AF_INET6;
sin6->sin6_port = dstPort.NotAnInteger;
sin6->sin6_addr = *(struct in6_addr*)&dst->ip.v6;
}
#endif
err = 0;
thisIntf = (PosixNetworkInterface *)(InterfaceID);
if (dst->type == mDNSAddrType_IPv4)
err = sendto(thisIntf->multicastSocket, msg, (char*)end - (char*)msg, 0, (struct sockaddr *)&to, GET_SA_LEN(to));
#ifdef mDNSIPv6Support
else if (dst->type == mDNSAddrType_IPv6)
err = sendto(thisIntf->multicastSocketv6, msg, (char*)end - (char*)msg, 0, (struct sockaddr *)&to, GET_SA_LEN(to));
#endif
if (err > 0) err = 0;
else if (err < 0)
verbosedebugf("mDNSPlatformSendUDP got error %d (%s) sending packet to %#a on interface %#a/%s/%d",
errno, strerror(errno), dst, &thisIntf->coreIntf.ip, thisIntf->intfName, thisIntf->index);
return PosixErrorToStatus(err);
}
mDNSexport int embedded_mDNSInit() {
mStatus err;
if (mDNSIsInitialized != 0) {
return 0;
}
mDNSPlatformMemZero( &mDNSStorage, sizeof(mDNSStorage));
mDNSPlatformMemZero( &platformSupport, sizeof(platformSupport));
// mDNSStorage.AutoTargetServices = 1;
err = mDNS_Init(
&mDNSStorage,
&platformSupport,
rrcachestorage,
RR_CACHE_SIZE,
mDNS_Init_AdvertiseLocalAddresses,
mDNS_Init_NoInitCallback,
mDNS_Init_NoInitCallbackContext
);
if (err)
return err;
#ifdef WIN32
platformSupport.reportStatusFunc = embedded_mDNSInit_ReportStatus;
err = SetupInterfaceList( &mDNSStorage );
if (err)
return err;
err = uDNS_SetupDNSConfig( &mDNSStorage );
#endif
if (err == 0) {
mDNSIsInitialized = 1;
}
return err;
}
mDNSlocal mDNSBool InitializeNSEC3Record(ResourceRecord *rr, const mDNSu8 *AnonData, int len, mDNSu32 salt)
{
const mDNSu8 *ptr;
rdataNSEC3 *nsec3 = (rdataNSEC3 *)rr->rdata->u.data;
mDNSu8 *tmp, *nxt;
unsigned short iter = ANON_NSEC3_ITERATIONS;
int hlen;
const mDNSu8 hashName[NSEC3_MAX_HASH_LEN];
// Construct the RDATA first and construct the owner name based on that.
ptr = (const mDNSu8 *)&salt;
debugf("InitializeNSEC3Record: %x%x%x%x, name %##s", ptr[0], ptr[1], ptr[2], ptr[3], rr->name->c);
// Set the RDATA
nsec3->alg = SHA1_DIGEST_TYPE;
nsec3->flags = 0;
nsec3->iterations = swap16(iter);
nsec3->saltLength = 4;
tmp = (mDNSu8 *)&nsec3->salt;
*tmp++ = ptr[0];
*tmp++ = ptr[1];
*tmp++ = ptr[2];
*tmp++ = ptr[3];
// hashLength, nxt, bitmap
*tmp++ = SHA1_HASH_LENGTH; // hash length
nxt = tmp;
tmp += SHA1_HASH_LENGTH;
*tmp++ = 0; // window number
*tmp++ = NSEC_MCAST_WINDOW_SIZE; // window length
mDNSPlatformMemZero(tmp, NSEC_MCAST_WINDOW_SIZE);
tmp[kDNSType_PTR >> 3] |= 128 >> (kDNSType_PTR & 7);
// Hash the base service name + salt + AnonData
if (!NSEC3HashName(rr->name, nsec3, AnonData, len, hashName, &hlen))
{
LogMsg("InitializeNSEC3Record: NSEC3HashName failed for ##s", rr->name->c);
return mDNSfalse;
}
if (hlen != SHA1_HASH_LENGTH)
{
LogMsg("InitializeNSEC3Record: hlen wrong %d", hlen);
return mDNSfalse;
}
mDNSPlatformMemCopy(nxt, hashName, hlen);
return mDNStrue;
}
mDNSexport mStatus LNT_UnmapPort(mDNS *m, NATTraversalInfo *n)
{
char externalPort[10];
Property propArgs[3];
tcpLNTInfo *info;
tcpLNTInfo **infoPtr = &m->tcpInfoUnmapList;
mStatus err;
// If no NAT gateway to talk to, no need to do all this work for nothing
if (mDNSIPPortIsZero(m->UPnPSOAPPort) || !m->UPnPSOAPURL || !m->UPnPSOAPAddressString) return mStatus_NoError;
mDNS_snprintf(externalPort, sizeof(externalPort), "%u", mDNSVal16(mDNSIPPortIsZero(n->RequestedPort) ? n->IntPort : n->RequestedPort));
mDNSPlatformMemZero(propArgs, sizeof(propArgs));
propArgs[0].name = "NewRemoteHost";
propArgs[0].type = "string";
propArgs[0].value = "";
propArgs[1].name = "NewExternalPort";
propArgs[1].type = "ui2";
propArgs[1].value = externalPort;
propArgs[2].name = "NewProtocol";
propArgs[2].type = "string";
propArgs[2].value = (n->Protocol == NATOp_MapUDP) ? "UDP" : "TCP";
n->tcpInfo.parentNATInfo = n;
// clean up previous port mapping requests and allocations
if (n->tcpInfo.sock) LogInfo("LNT_UnmapPort: closing previous open connection");
if (n->tcpInfo.sock ) { mDNSPlatformTCPCloseConnection(n->tcpInfo.sock); n->tcpInfo.sock = mDNSNULL; }
if (n->tcpInfo.Request) { mDNSPlatformMemFree(n->tcpInfo.Request); n->tcpInfo.Request = mDNSNULL; }
if (n->tcpInfo.Reply ) { mDNSPlatformMemFree(n->tcpInfo.Reply); n->tcpInfo.Reply = mDNSNULL; }
// make a copy of the tcpInfo that we can clean up later (the one passed in will be destroyed by the client as soon as this returns)
if ((info = mDNSPlatformMemAllocate(sizeof(tcpLNTInfo))) == mDNSNULL)
{ LogInfo("LNT_UnmapPort: can't allocate tcpInfo"); return(mStatus_NoMemoryErr); }
*info = n->tcpInfo;
while (*infoPtr) infoPtr = &(*infoPtr)->next; // find the end of the list
*infoPtr = info; // append
err = SendSOAPMsgControlAction(m, info, "DeletePortMapping", 3, propArgs, LNTPortMapDeleteOp);
if (err) DisposeInfoFromUnmapList(m, info);
return err;
}
mDNSlocal mStatus MakeTCPConnection(mDNS *const m, tcpLNTInfo *info, const mDNSAddr *const Addr, const mDNSIPPort Port, LNTOp_t op)
{
mStatus err = mStatus_NoError;
mDNSIPPort srcport = zeroIPPort;
if (mDNSIPv4AddressIsZero(Addr->ip.v4) || mDNSIPPortIsZero(Port))
{ LogMsg("LNT MakeTCPConnection: bad address/port %#a:%d", Addr, mDNSVal16(Port)); return(mStatus_Invalid); }
info->m = m;
info->Address = *Addr;
info->Port = Port;
info->op = op;
info->nread = 0;
info->replyLen = LNT_MAXBUFSIZE;
if (info->Reply != mDNSNULL) mDNSPlatformMemZero(info->Reply, LNT_MAXBUFSIZE); // reuse previously allocated buffer
else if ((info->Reply = (mDNSs8 *) mDNSPlatformMemAllocate(LNT_MAXBUFSIZE)) == mDNSNULL) { LogInfo("can't allocate reply buffer"); return (mStatus_NoMemoryErr); }
if (info->sock) { LogInfo("MakeTCPConnection: closing previous open connection"); mDNSPlatformTCPCloseConnection(info->sock); info->sock = mDNSNULL; }
info->sock = mDNSPlatformTCPSocket(m, kTCPSocketFlags_Zero, &srcport);
if (!info->sock) { LogMsg("LNT MakeTCPConnection: unable to create TCP socket"); mDNSPlatformMemFree(info->Reply); info->Reply = mDNSNULL; return(mStatus_NoMemoryErr); }
LogInfo("MakeTCPConnection: connecting to %#a:%d", &info->Address, mDNSVal16(info->Port));
err = mDNSPlatformTCPConnect(info->sock, Addr, Port, 0, tcpConnectionCallback, info);
if (err == mStatus_ConnPending) err = mStatus_NoError;
else if (err == mStatus_ConnEstablished)
{
mDNS_DropLockBeforeCallback();
tcpConnectionCallback(info->sock, info, mDNStrue, mStatus_NoError);
mDNS_ReclaimLockAfterCallback();
err = mStatus_NoError;
}
else
{
// Don't need to log this in customer builds -- it happens quite often during sleep, wake, configuration changes, etc.
LogInfo("LNT MakeTCPConnection: connection failed");
mDNSPlatformTCPCloseConnection(info->sock); // Dispose the socket we created with mDNSPlatformTCPSocket() above
info->sock = mDNSNULL;
mDNSPlatformMemFree(info->Reply);
info->Reply = mDNSNULL;
}
return(err);
}
mDNSlocal mStatus GetDeviceDescription(mDNS *m, tcpLNTInfo *info)
{
// Device description format -
// - device description URL
// - host/port
static const char szSSDPMsgDescribeDeviceFMT[] =
"GET %s HTTP/1.1\r\n"
"Accept: text/xml, application/xml\r\n"
"User-Agent: Mozilla/4.0 (compatible; UPnP/1.0; Windows NT/5.1)\r\n"
"Host: %s\r\n"
"Connection: close\r\n"
"\r\n";
if (!mDNSIPPortIsZero(m->UPnPSOAPPort)) return mStatus_NoError; // already have the info we need
if (m->UPnPRouterURL == mDNSNULL || m->UPnPRouterAddressString == mDNSNULL) { LogInfo("GetDeviceDescription: no router URL or address string!"); return (mStatus_Invalid); }
// build message
if (info->Request != mDNSNULL) mDNSPlatformMemZero(info->Request, LNT_MAXBUFSIZE); // reuse previously allocated buffer
else if ((info->Request = (mDNSs8 *) mDNSPlatformMemAllocate(LNT_MAXBUFSIZE)) == mDNSNULL) { LogInfo("can't allocate send buffer for discovery"); return (mStatus_NoMemoryErr); }
info->requestLen = mDNS_snprintf((char *)info->Request, LNT_MAXBUFSIZE, szSSDPMsgDescribeDeviceFMT, m->UPnPRouterURL, m->UPnPRouterAddressString);
LogInfo("Describe Device: [%s]", info->Request);
return MakeTCPConnection(m, info, &m->Router, m->UPnPRouterPort, LNTDiscoveryOp);
}
mDNSlocal void ProxyTCPSocketCallBack(int s1, short filter, void *context)
{
int ret;
struct sockaddr_storage from;
struct sockaddr_storage to;
mDNSAddr senderAddr, destAddr;
mDNSIPPort senderPort;
ProxyTCPInfo_t *ti = (ProxyTCPInfo_t *)context;
TCPSocket *sock = &ti->sock;
KQSocketSet *kq = &sock->ss;
(void) filter;
ret = ProxyTCPRead(ti);
if (ret == -1)
{
mDNSPlatformDisposeProxyContext(ti);
return;
}
else if (!ret)
{
debugf("ProxyTCPReceive: Not yet read completely Actual length %d, Read length %d", ti->replyLen, ti->nread);
return;
}
// We read all the data and hence not interested in read events anymore
KQueueSet(s1, EV_DELETE, EVFILT_READ, sock->kqEntry);
mDNSPlatformMemZero(&to, sizeof(to));
mDNSPlatformMemZero(&from, sizeof(from));
socklen_t len = sizeof(to);
ret = getsockname(s1, (struct sockaddr*) &to, &len);
if (ret < 0)
{
LogMsg("ProxyTCPReceive: getsockname(fd=%d) errno %d", s1, errno);
mDNSPlatformDisposeProxyContext(ti);
return;
}
ret = getpeername(s1, (struct sockaddr*) &from, &len);
if (ret < 0)
{
LogMsg("ProxyTCPReceive: getpeername(fd=%d) errno %d", s1, errno);
mDNSPlatformDisposeProxyContext(ti);
return;
}
if (from.ss_family == AF_INET)
{
struct sockaddr_in *s = (struct sockaddr_in*)&from;
senderAddr.type = mDNSAddrType_IPv4;
senderAddr.ip.v4.NotAnInteger = s->sin_addr.s_addr;
senderPort.NotAnInteger = s->sin_port;
s = (struct sockaddr_in *)&to;
destAddr.type = mDNSAddrType_IPv4;
destAddr.ip.v4.NotAnInteger = s->sin_addr.s_addr;
LogInfo("ProxyTCPReceive received IPv4 packet(len %d) from %#-15a to %#-15a on skt %d %s", ti->replyLen, &senderAddr, &destAddr, s1, NULL);
}
else if (from.ss_family == AF_INET6)
{
struct sockaddr_in6 *sin6 = (struct sockaddr_in6*)&from;
senderAddr.type = mDNSAddrType_IPv6;
senderAddr.ip.v6 = *(mDNSv6Addr*)&sin6->sin6_addr;
senderPort.NotAnInteger = sin6->sin6_port;
sin6 = (struct sockaddr_in6 *)&to;
destAddr.type = mDNSAddrType_IPv6;
destAddr.ip.v6 = *(mDNSv6Addr*)&sin6->sin6_addr;
LogInfo("ProxyTCPReceive received IPv6 packet(len %d) from %#-15a to %#-15a on skt %d %s", ti->replyLen, &senderAddr, &destAddr, s1, NULL);
}
else
{
LogMsg("ProxyTCPReceive from is unknown address family %d", from.ss_family);
mDNSPlatformDisposeProxyContext(ti);
return;
}
// We pass sock for the TCPSocket and the "ti" for context as that's what we want to free at the end.
// In the UDP case, there is just a single socket and nothing to free. Hence, the context (last argument)
// would be NULL.
kq->m->p->TCPProxyCallback(kq->m, sock, ti->reply, (mDNSu8 *)ti->reply + ti->replyLen, &senderAddr, senderPort, &destAddr,
UnicastDNSPort, 0, ti);
}
mDNSlocal void ProxyTCPAccept(int s1, short filter, void *context)
{
int newfd;
struct sockaddr_storage ss;
socklen_t sslen = sizeof(ss);
const int on = 1;
KQSocketSet *listenSet = (KQSocketSet *)context;
(void) filter;
while ((newfd = accept(s1, (struct sockaddr *)&ss, &sslen)) != -1)
{
int err;
int *s;
KQueueEntry *k;
KQSocketSet *kq;
// Even though we just need a single KQueueEntry, for simplicity we re-use
// the KQSocketSet
ProxyTCPInfo_t *ti = mallocL("ProxyTCPContext", sizeof(ProxyTCPInfo_t));
if (!ti)
{
LogMsg("ProxyTCPAccept: cannot allocate TCPSocket");
close(newfd);
return;
}
mDNSPlatformMemZero(ti, sizeof(ProxyTCPInfo_t));
TCPSocket *sock = &ti->sock;
kq = &sock->ss;
kq->sktv4 = -1;
kq->sktv6 = -1;
kq->m = listenSet->m;
fcntl(newfd, F_SETFL, fcntl(newfd, F_GETFL, 0) | O_NONBLOCK); // set non-blocking
if (ss.ss_family == AF_INET)
{
s = &kq->sktv4;
k = &kq->kqsv4;
// Receive interface identifiers
err = setsockopt(newfd, IPPROTO_IP, IP_RECVIF, &on, sizeof(on));
if (err)
{
LogMsg("ProxyTCPAccept: IP_RECVIF %d errno %d (%s)", newfd, errno, strerror(errno));
mDNSPlatformDisposeProxyContext(ti);
return;
}
}
else
{
s = &kq->sktv6;
k = &kq->kqsv6;
// We want to receive destination addresses and receive interface identifiers
err = setsockopt(newfd, IPPROTO_IPV6, IPV6_RECVPKTINFO, &on, sizeof(on));
if (err)
{
LogMsg("ProxyTCPAccept: IP_RECVPKTINFO %d errno %d (%s)", newfd, errno, strerror(errno));
mDNSPlatformDisposeProxyContext(ti);
return;
}
}
*s = newfd;
// mDNSPlatformReadTCP/WriteTCP (unlike the UDP counterpart) does not provide the destination address
// from which we can infer the destination address family. Hence we need to remember that here.
// Instead of remembering the address family, we remember the right fd.
sock->fd = newfd;
sock->kqEntry = k;
k->KQcallback = ProxyTCPSocketCallBack;
k->KQcontext = ti;
k->KQtask = "TCP Proxy packet reception";
#ifdef MDNSRESPONDER_USES_LIB_DISPATCH_AS_PRIMARY_EVENT_LOOP_MECHANISM
k->readSource = mDNSNULL;
k->writeSource = mDNSNULL;
k->fdClosed = mDNSfalse;
#endif
KQueueSet(*s, EV_ADD, EVFILT_READ, k);
}
}
// Sets up a multicast send/receive socket for the specified
// port on the interface specified by the IP addrelss intfAddr.
static int SetupSocket(struct sockaddr *intfAddr, mDNSIPPort port, int interfaceIndex, int *sktPtr)
{
int err = 0;
static const int kOn = 1;
static const int kIntTwoFiveFive = 255;
static const unsigned char kByteTwoFiveFive = 255;
(void) interfaceIndex; // Unused
assert(intfAddr != NULL);
assert(sktPtr != NULL);
assert(*sktPtr == -1);
// Open the socket...
if (intfAddr->sa_family == AF_INET) *sktPtr = socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
#ifdef mDNSIPv6Support
else if (intfAddr->sa_family == AF_INET6) *sktPtr = socket(PF_INET6, SOCK_DGRAM, IPPROTO_UDP);
#endif
else return EINVAL;
if (*sktPtr < 0) { err = errno; perror("socket"); }
// ... with a shared UDP port
if (err == 0)
{
#if defined(SO_REUSEPORT)
err = setsockopt(*sktPtr, SOL_SOCKET, SO_REUSEPORT, &kOn, sizeof(kOn));
#elif defined(SO_REUSEADDR)
err = setsockopt(*sktPtr, SOL_SOCKET, SO_REUSEADDR, &kOn, sizeof(kOn));
#else
#error This platform has no way to avoid address busy errors on multicast.
#endif
if (err < 0) { err = errno; perror("setsockopt - SO_REUSExxxx"); }
}
// We want to receive destination addresses and interface identifiers.
if (intfAddr->sa_family == AF_INET)
{
struct ip_mreq imr;
struct sockaddr_in bindAddr;
if (err == 0)
{
#if defined(IP_PKTINFO) // Linux
err = setsockopt(*sktPtr, IPPROTO_IP, IP_PKTINFO, &kOn, sizeof(kOn));
if (err < 0) { err = errno; perror("setsockopt - IP_PKTINFO"); }
#elif defined(IP_RECVDSTADDR) || defined(IP_RECVIF) // BSD and Solaris
#if defined(IP_RECVDSTADDR)
err = setsockopt(*sktPtr, IPPROTO_IP, IP_RECVDSTADDR, &kOn, sizeof(kOn));
if (err < 0) { err = errno; perror("setsockopt - IP_RECVDSTADDR"); }
#endif
#if defined(IP_RECVIF)
if (err == 0)
{
err = setsockopt(*sktPtr, IPPROTO_IP, IP_RECVIF, &kOn, sizeof(kOn));
if (err < 0) { err = errno; perror("setsockopt - IP_RECVIF"); }
}
#endif
#else
#warning This platform has no way to get the destination interface information -- will only work for single-homed hosts
#endif
}
// Add multicast group membership on this interface
if (err == 0)
{
imr.imr_multiaddr.s_addr = AllDNSLinkGroup.NotAnInteger;
imr.imr_interface = ((struct sockaddr_in*)intfAddr)->sin_addr;
err = setsockopt(*sktPtr, IPPROTO_IP, IP_ADD_MEMBERSHIP, &imr, sizeof(imr));
if (err < 0) { err = errno; perror("setsockopt - IP_ADD_MEMBERSHIP"); }
}
// Specify outgoing interface too
if (err == 0)
{
err = setsockopt(*sktPtr, IPPROTO_IP, IP_MULTICAST_IF, &((struct sockaddr_in*)intfAddr)->sin_addr, sizeof(struct in_addr));
if (err < 0) { err = errno; perror("setsockopt - IP_MULTICAST_IF"); }
}
// Per the mDNS spec, send unicast packets with TTL 255
if (err == 0)
{
err = setsockopt(*sktPtr, IPPROTO_IP, IP_TTL, &kIntTwoFiveFive, sizeof(kIntTwoFiveFive));
if (err < 0) { err = errno; perror("setsockopt - IP_TTL"); }
}
// and multicast packets with TTL 255 too
// There's some debate as to whether IP_MULTICAST_TTL is an int or a byte so we just try both.
if (err == 0)
{
err = setsockopt(*sktPtr, IPPROTO_IP, IP_MULTICAST_TTL, &kByteTwoFiveFive, sizeof(kByteTwoFiveFive));
if (err < 0 && errno == EINVAL)
err = setsockopt(*sktPtr, IPPROTO_IP, IP_MULTICAST_TTL, &kIntTwoFiveFive, sizeof(kIntTwoFiveFive));
if (err < 0) { err = errno; perror("setsockopt - IP_MULTICAST_TTL"); }
}
// And start listening for packets
if (err == 0)
{
bindAddr.sin_family = AF_INET;
bindAddr.sin_port = port.NotAnInteger;
bindAddr.sin_addr.s_addr = INADDR_ANY; // Want to receive multicasts AND unicasts on this socket
err = bind(*sktPtr, (struct sockaddr *) &bindAddr, sizeof(bindAddr));
if (err < 0) { err = errno; perror("bind"); fflush(stderr); }
}
} // endif (intfAddr->sa_family == AF_INET)
#ifdef mDNSIPv6Support
else if (intfAddr->sa_family == AF_INET6)
{
struct ipv6_mreq imr6;
struct sockaddr_in6 bindAddr6;
if (err == 0)
{
#if defined(IPV6_PKTINFO)
err = setsockopt(*sktPtr, IPPROTO_IPV6, IPV6_PKTINFO, &kOn, sizeof(kOn));
if (err < 0) { err = errno; perror("setsockopt - IPV6_PKTINFO"); }
#else
#warning This platform has no way to get the destination interface information for IPv6 -- will only work for single-homed hosts
#endif
}
// Add multicast group membership on this interface
if (err == 0)
{
imr6.ipv6mr_multiaddr = *(const struct in6_addr*)&AllDNSLinkGroupv6;
imr6.ipv6mr_interface = interfaceIndex;
err = setsockopt(*sktPtr, IPPROTO_IPV6, IPV6_JOIN_GROUP, &imr6, sizeof(imr6));
if (err < 0)
{
err = errno;
verbosedebugf("IPV6_JOIN_GROUP %.16a on %d failed.\n", &imr6.ipv6mr_multiaddr, imr6.ipv6mr_interface);
perror("setsockopt - IPV6_JOIN_GROUP");
}
}
// Specify outgoing interface too
if (err == 0)
{
u_int multicast_if = interfaceIndex;
err = setsockopt(*sktPtr, IPPROTO_IPV6, IPV6_MULTICAST_IF, &multicast_if, sizeof(multicast_if));
if (err < 0) { err = errno; perror("setsockopt - IPV6_MULTICAST_IF"); }
}
// We want to receive only IPv6 packets on this socket.
// Without this option, we may get IPv4 addresses as mapped addresses.
if (err == 0)
{
err = setsockopt(*sktPtr, IPPROTO_IPV6, IPV6_V6ONLY, &kOn, sizeof(kOn));
if (err < 0) { err = errno; perror("setsockopt - IPV6_V6ONLY"); }
}
// Per the mDNS spec, send unicast packets with TTL 255
if (err == 0)
{
err = setsockopt(*sktPtr, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &kIntTwoFiveFive, sizeof(kIntTwoFiveFive));
if (err < 0) { err = errno; perror("setsockopt - IPV6_UNICAST_HOPS"); }
}
// and multicast packets with TTL 255 too
// There's some debate as to whether IPV6_MULTICAST_HOPS is an int or a byte so we just try both.
if (err == 0)
{
err = setsockopt(*sktPtr, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &kByteTwoFiveFive, sizeof(kByteTwoFiveFive));
if (err < 0 && errno == EINVAL)
err = setsockopt(*sktPtr, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &kIntTwoFiveFive, sizeof(kIntTwoFiveFive));
if (err < 0) { err = errno; perror("setsockopt - IPV6_MULTICAST_HOPS"); }
}
// And start listening for packets
if (err == 0)
{
mDNSPlatformMemZero(&bindAddr6, sizeof(bindAddr6));
bindAddr6.sin6_len = sizeof(bindAddr6);
bindAddr6.sin6_family = AF_INET6;
bindAddr6.sin6_port = port.NotAnInteger;
bindAddr6.sin6_flowinfo = 0;
// bindAddr6.sin6_addr.s_addr = IN6ADDR_ANY_INIT; // Want to receive multicasts AND unicasts on this socket
bindAddr6.sin6_scope_id = 0;
err = bind(*sktPtr, (struct sockaddr *) &bindAddr6, sizeof(bindAddr6));
if (err < 0) { err = errno; perror("bind"); fflush(stderr); }
}
} // endif (intfAddr->sa_family == AF_INET6)
#endif
// Set the socket to non-blocking.
if (err == 0)
{
err = fcntl(*sktPtr, F_GETFL, 0);
if (err < 0) err = errno;
else
{
err = fcntl(*sktPtr, F_SETFL, err | O_NONBLOCK);
if (err < 0) err = errno;
}
}
// Clean up
if (err != 0 && *sktPtr != -1) { assert(close(*sktPtr) == 0); *sktPtr = -1; }
assert( (err == 0) == (*sktPtr != -1) );
return err;
}
// If the answer was result of a wildcard match, then this function proves
// that a proper wildcard was used to answer the question and that the
// original name does not exist
mDNSexport void WildcardAnswerProof(mDNS *const m, DNSSECVerifier *dv)
{
CacheRecord *ncr;
CacheRecord **rp;
const domainname *ce;
DNSQuestion q;
CacheRecord **nsec3 = mDNSNULL;
LogDNSSEC("WildcardAnswerProof: Question %##s (%s)", dv->origName.c, DNSTypeName(dv->origType));
//
// RFC 4035: Section 3.1.3.3
//
// 1) We used a wildcard because the qname does not exist, so verify
// that the qname does not exist
//
// 2) Is the wildcard the right one ?
//
// Unfortunately, this is not well explained in that section. Refer to
// RFC 5155 section 7.2.6.
// Walk the list of nsecs we received and see if they prove that
// the name does not exist
mDNSPlatformMemZero(&q, sizeof(DNSQuestion));
q.ThisQInterval = -1;
InitializeQuestion(m, &q, dv->InterfaceID, &dv->origName, dv->origType, mDNSNULL, mDNSNULL);
ncr = NSECParentForQuestion(m, &q);
if (!ncr)
{
LogMsg("WildcardAnswerProof: Can't find NSEC Parent for %##s (%s)", q.qname.c, DNSTypeName(q.qtype));
goto error;
}
else
{
LogDNSSEC("WildcardAnswerProof: found %s", CRDisplayString(m, ncr));
}
rp = &(ncr->nsec);
while (*rp)
{
if ((*rp)->resrec.rrtype == kDNSType_NSEC)
{
CacheRecord *cr = *rp;
if (!NSECNameExists(m, &cr->resrec, &dv->origName, dv->origType))
break;
}
else if ((*rp)->resrec.rrtype == kDNSType_NSEC3)
{
nsec3 = rp;
}
rp=&(*rp)->next;
}
if (!(*rp))
{
mDNSBool ret = mDNSfalse;
if (nsec3)
{
ret = NSEC3WildcardAnswerProof(m, ncr, dv);
}
if (!ret)
{
LogDNSSEC("WildcardAnswerProof: NSEC3 wildcard proof failed for %##s (%s)", q.qname.c, DNSTypeName(q.qtype));
goto error;
}
rp = nsec3;
}
else
{
ce = NSECClosestEncloser(&((*rp)->resrec), &dv->origName);
if (!ce)
{
LogMsg("WildcardAnswerProof: ERROR!! Closest Encloser NULL for %##s (%s)", q.qname.c, DNSTypeName(q.qtype));
goto error;
}
if (!SameDomainName(ce, dv->wildcardName))
{
LogMsg("WildcardAnswerProof: ERROR!! Closest Encloser %##s does not match wildcard name %##s", q.qname.c, dv->wildcardName->c);
goto error;
}
}
VerifyNSEC(m, &((*rp)->resrec), mDNSNULL, dv, ncr, mDNSNULL);
return;
error:
dv->DVCallback(m, dv, DNSSEC_Bogus);
}
// Build port mapping request with new port (up to max) and send it
mDNSlocal mStatus SendPortMapRequest(mDNS *m, NATTraversalInfo *n)
{
char externalPort[6];
char internalPort[6];
char localIPAddrString[30];
char publicPortString[40];
Property propArgs[8];
mDNSu16 ReqPortNum = RequestedPortNum(n);
NATTraversalInfo *n2 = m->NATTraversals;
// Scan our m->NATTraversals list to make sure the external port we're requesting is locally unique.
// UPnP gateways will report conflicts if different devices request the same external port, but if two
// clients on the same device request the same external port the second one just stomps over the first.
// One way this can happen is like this:
// 1. Client A binds local port 80
// 2. Client A requests external port 80 -> internal port 80
// 3. UPnP NAT gateway refuses external port 80 (some other client already has it)
// 4. Client A tries again, and successfully gets external port 80 -> internal port 81
// 5. Client B on same machine tries to bind local port 80, and fails
// 6. Client B tries again, and successfully binds local port 81
// 7. Client B now requests external port 81 -> internal port 81
// 8. UPnP NAT gateway allows this, stomping over Client A's existing mapping
while (n2)
{
if (n2 == n || RequestedPortNum(n2) != ReqPortNum) n2=n2->next;
else
{
if (n->tcpInfo.retries < 100)
{
n->tcpInfo.retries++;
ReqPortNum = RequestedPortNum(n); // Pick a new port number
n2 = m->NATTraversals; // And re-scan the list looking for conflicts
}
else
{
natTraversalHandlePortMapReply(m, n, m->UPnPInterfaceID, NATErr_Res, zeroIPPort, 0);
return mStatus_NoError;
}
}
}
// create strings to use in the message
mDNS_snprintf(externalPort, sizeof(externalPort), "%u", ReqPortNum);
mDNS_snprintf(internalPort, sizeof(internalPort), "%u", mDNSVal16(n->IntPort));
mDNS_snprintf(publicPortString, sizeof(publicPortString), "iC%u", ReqPortNum);
mDNS_snprintf(localIPAddrString, sizeof(localIPAddrString), "%u.%u.%u.%u",
m->AdvertisedV4.ip.v4.b[0], m->AdvertisedV4.ip.v4.b[1], m->AdvertisedV4.ip.v4.b[2], m->AdvertisedV4.ip.v4.b[3]);
// build the message
mDNSPlatformMemZero(propArgs, sizeof(propArgs));
propArgs[0].name = "NewRemoteHost";
propArgs[0].type = "string";
propArgs[0].value = "";
propArgs[1].name = "NewExternalPort";
propArgs[1].type = "ui2";
propArgs[1].value = externalPort;
propArgs[2].name = "NewProtocol";
propArgs[2].type = "string";
propArgs[2].value = (n->Protocol == NATOp_MapUDP) ? "UDP" : "TCP";
propArgs[3].name = "NewInternalPort";
propArgs[3].type = "ui2";
propArgs[3].value = internalPort;
propArgs[4].name = "NewInternalClient";
propArgs[4].type = "string";
propArgs[4].value = localIPAddrString;
propArgs[5].name = "NewEnabled";
propArgs[5].type = "boolean";
propArgs[5].value = "1";
propArgs[6].name = "NewPortMappingDescription";
propArgs[6].type = "string";
propArgs[6].value = publicPortString;
propArgs[7].name = "NewLeaseDuration";
propArgs[7].type = "ui4";
propArgs[7].value = "0";
LogInfo("SendPortMapRequest: internal %u external %u", mDNSVal16(n->IntPort), ReqPortNum);
return SendSOAPMsgControlAction(m, &n->tcpInfo, "AddPortMapping", 8, propArgs, LNTPortMapOp);
}