Initial code submission for mDnsSd
AKA known as Bonjour.
Change-Id: I7ddf2238deaebe1bdd4c5da83b5ec9038ebec5c6
diff --git a/mDNSPosix/mDNSPosix.c b/mDNSPosix/mDNSPosix.c
new file mode 100755
index 0000000..74a2161
--- /dev/null
+++ b/mDNSPosix/mDNSPosix.c
@@ -0,0 +1,1621 @@
+/* -*- Mode: C; tab-width: 4 -*-
+ *
+ * Copyright (c) 2002-2004 Apple Computer, Inc. All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * Formatting notes:
+ * This code follows the "Whitesmiths style" C indentation rules. Plenty of discussion
+ * on C indentation can be found on the web, such as <http://www.kafejo.com/komp/1tbs.htm>,
+ * but for the sake of brevity here I will say just this: Curly braces are not syntactially
+ * part of an "if" statement; they are the beginning and ending markers of a compound statement;
+ * therefore common sense dictates that if they are part of a compound statement then they
+ * should be indented to the same level as everything else in that compound statement.
+ * Indenting curly braces at the same level as the "if" implies that curly braces are
+ * part of the "if", which is false. (This is as misleading as people who write "char* x,y;"
+ * thinking that variables x and y are both of type "char*" -- and anyone who doesn't
+ * understand why variable y is not of type "char*" just proves the point that poor code
+ * layout leads people to unfortunate misunderstandings about how the C language really works.)
+ */
+
+#include "mDNSEmbeddedAPI.h" // Defines the interface provided to the client layer above
+#include "DNSCommon.h"
+#include "mDNSPosix.h" // Defines the specific types needed to run mDNS on this platform
+#include "dns_sd.h"
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+#include <syslog.h>
+#include <stdarg.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/time.h>
+#include <sys/socket.h>
+#include <sys/uio.h>
+#include <sys/select.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <time.h> // platform support for UTC time
+
+#if USES_NETLINK
+#include <asm/types.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+#else // USES_NETLINK
+#include <net/route.h>
+#include <net/if.h>
+#endif // USES_NETLINK
+
+#include "mDNSUNP.h"
+#include "GenLinkedList.h"
+
+// ***************************************************************************
+// Structures
+
+// We keep a list of client-supplied event sources in PosixEventSource records
+struct PosixEventSource
+ {
+ mDNSPosixEventCallback Callback;
+ void *Context;
+ int fd;
+ struct PosixEventSource *Next;
+ };
+typedef struct PosixEventSource PosixEventSource;
+
+// Context record for interface change callback
+struct IfChangeRec
+ {
+ int NotifySD;
+ mDNS *mDNS;
+ };
+typedef struct IfChangeRec IfChangeRec;
+
+// Note that static data is initialized to zero in (modern) C.
+static fd_set gEventFDs;
+static int gMaxFD; // largest fd in gEventFDs
+static GenLinkedList gEventSources; // linked list of PosixEventSource's
+static sigset_t gEventSignalSet; // Signals which event loop listens for
+static sigset_t gEventSignals; // Signals which were received while inside loop
+
+// ***************************************************************************
+// Globals (for debugging)
+
+static int num_registered_interfaces = 0;
+static int num_pkts_accepted = 0;
+static int num_pkts_rejected = 0;
+
+// ***************************************************************************
+// Functions
+
+int gMDNSPlatformPosixVerboseLevel = 0;
+
+#define PosixErrorToStatus(errNum) ((errNum) == 0 ? mStatus_NoError : mStatus_UnknownErr)
+
+mDNSlocal void SockAddrTomDNSAddr(const struct sockaddr *const sa, mDNSAddr *ipAddr, mDNSIPPort *ipPort)
+ {
+ switch (sa->sa_family)
+ {
+ case AF_INET:
+ {
+ struct sockaddr_in *sin = (struct sockaddr_in*)sa;
+ ipAddr->type = mDNSAddrType_IPv4;
+ ipAddr->ip.v4.NotAnInteger = sin->sin_addr.s_addr;
+ if (ipPort) ipPort->NotAnInteger = sin->sin_port;
+ break;
+ }
+
+#if HAVE_IPV6
+ case AF_INET6:
+ {
+ struct sockaddr_in6 *sin6 = (struct sockaddr_in6*)sa;
+#ifndef NOT_HAVE_SA_LEN
+ assert(sin6->sin6_len == sizeof(*sin6));
+#endif
+ ipAddr->type = mDNSAddrType_IPv6;
+ ipAddr->ip.v6 = *(mDNSv6Addr*)&sin6->sin6_addr;
+ if (ipPort) ipPort->NotAnInteger = sin6->sin6_port;
+ break;
+ }
+#endif
+
+ default:
+ verbosedebugf("SockAddrTomDNSAddr: Uknown address family %d\n", sa->sa_family);
+ ipAddr->type = mDNSAddrType_None;
+ if (ipPort) ipPort->NotAnInteger = 0;
+ break;
+ }
+ }
+
+#if COMPILER_LIKES_PRAGMA_MARK
+#pragma mark ***** Send and Receive
+#endif
+
+// mDNS core calls this routine when it needs to send a packet.
+mDNSexport mStatus mDNSPlatformSendUDP(const mDNS *const m, const void *const msg, const mDNSu8 *const end,
+ mDNSInterfaceID InterfaceID, UDPSocket *src, const mDNSAddr *dst, mDNSIPPort dstPort)
+ {
+ int err = 0;
+ struct sockaddr_storage to;
+ PosixNetworkInterface * thisIntf = (PosixNetworkInterface *)(InterfaceID);
+ int sendingsocket = -1;
+
+ (void)src; // Will need to use this parameter once we implement mDNSPlatformUDPSocket/mDNSPlatformUDPClose
+
+ assert(m != NULL);
+ assert(msg != NULL);
+ assert(end != NULL);
+ assert((((char *) end) - ((char *) msg)) > 0);
+
+ if (dstPort.NotAnInteger == 0)
+ {
+ LogMsg("mDNSPlatformSendUDP: Invalid argument -dstPort is set to 0");
+ return PosixErrorToStatus(EINVAL);
+ }
+ 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;
+ sendingsocket = thisIntf ? thisIntf->multicastSocket4 : m->p->unicastSocket4;
+ }
+
+#if HAVE_IPV6
+ else if (dst->type == mDNSAddrType_IPv6)
+ {
+ struct sockaddr_in6 *sin6 = (struct sockaddr_in6*)&to;
+ mDNSPlatformMemZero(sin6, sizeof(*sin6));
+#ifndef NOT_HAVE_SA_LEN
+ sin6->sin6_len = sizeof(*sin6);
+#endif
+ sin6->sin6_family = AF_INET6;
+ sin6->sin6_port = dstPort.NotAnInteger;
+ sin6->sin6_addr = *(struct in6_addr*)&dst->ip.v6;
+ sendingsocket = thisIntf ? thisIntf->multicastSocket6 : m->p->unicastSocket6;
+ }
+#endif
+
+ if (sendingsocket >= 0)
+ err = sendto(sendingsocket, msg, (char*)end - (char*)msg, 0, (struct sockaddr *)&to, GET_SA_LEN(to));
+
+ if (err > 0) err = 0;
+ else if (err < 0)
+ {
+ static int MessageCount = 0;
+ // Don't report EHOSTDOWN (i.e. ARP failure), ENETDOWN, or no route to host for unicast destinations
+ if (!mDNSAddressIsAllDNSLinkGroup(dst))
+ if (errno == EHOSTDOWN || errno == ENETDOWN || errno == EHOSTUNREACH || errno == ENETUNREACH) return(mStatus_TransientErr);
+
+ if (MessageCount < 1000)
+ {
+ MessageCount++;
+ if (thisIntf)
+ LogMsg("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);
+ else
+ LogMsg("mDNSPlatformSendUDP got error %d (%s) sending packet to %#a", errno, strerror(errno), dst);
+ }
+ }
+
+ return PosixErrorToStatus(err);
+ }
+
+// This routine is called when the main loop detects that data is available on a socket.
+mDNSlocal void SocketDataReady(mDNS *const m, PosixNetworkInterface *intf, int skt)
+ {
+ mDNSAddr senderAddr, destAddr;
+ mDNSIPPort senderPort;
+ ssize_t packetLen;
+ DNSMessage packet;
+ struct my_in_pktinfo packetInfo;
+ struct sockaddr_storage from;
+ socklen_t fromLen;
+ int flags;
+ mDNSu8 ttl;
+ mDNSBool reject;
+ const mDNSInterfaceID InterfaceID = intf ? intf->coreIntf.InterfaceID : NULL;
+
+ assert(m != NULL);
+ assert(skt >= 0);
+
+ fromLen = sizeof(from);
+ flags = 0;
+ packetLen = recvfrom_flags(skt, &packet, sizeof(packet), &flags, (struct sockaddr *) &from, &fromLen, &packetInfo, &ttl);
+
+ if (packetLen >= 0)
+ {
+ SockAddrTomDNSAddr((struct sockaddr*)&from, &senderAddr, &senderPort);
+ SockAddrTomDNSAddr((struct sockaddr*)&packetInfo.ipi_addr, &destAddr, NULL);
+
+ // If we have broken IP_RECVDSTADDR functionality (so far
+ // I've only seen this on OpenBSD) then apply a hack to
+ // convince mDNS Core that this isn't a spoof packet.
+ // Basically what we do is check to see whether the
+ // packet arrived as a multicast and, if so, set its
+ // destAddr to the mDNS address.
+ //
+ // I must admit that I could just be doing something
+ // wrong on OpenBSD and hence triggering this problem
+ // but I'm at a loss as to how.
+ //
+ // If this platform doesn't have IP_PKTINFO or IP_RECVDSTADDR, then we have
+ // no way to tell the destination address or interface this packet arrived on,
+ // so all we can do is just assume it's a multicast
+
+ #if HAVE_BROKEN_RECVDSTADDR || (!defined(IP_PKTINFO) && !defined(IP_RECVDSTADDR))
+ if ((destAddr.NotAnInteger == 0) && (flags & MSG_MCAST))
+ {
+ destAddr.type = senderAddr.type;
+ if (senderAddr.type == mDNSAddrType_IPv4) destAddr.ip.v4 = AllDNSLinkGroup_v4.ip.v4;
+ else if (senderAddr.type == mDNSAddrType_IPv6) destAddr.ip.v6 = AllDNSLinkGroup_v6.ip.v6;
+ }
+ #endif
+
+ // We only accept the packet if the interface on which it came
+ // in matches the interface associated with this socket.
+ // We do this match by name or by index, depending on which
+ // information is available. recvfrom_flags sets the name
+ // to "" if the name isn't available, or the index to -1
+ // if the index is available. This accomodates the various
+ // different capabilities of our target platforms.
+
+ reject = mDNSfalse;
+ if (!intf)
+ {
+ // Ignore multicasts accidentally delivered to our unicast receiving socket
+ if (mDNSAddrIsDNSMulticast(&destAddr)) packetLen = -1;
+ }
+ else
+ {
+ if (packetInfo.ipi_ifname[0] != 0) reject = (strcmp(packetInfo.ipi_ifname, intf->intfName) != 0);
+ else if (packetInfo.ipi_ifindex != -1) reject = (packetInfo.ipi_ifindex != intf->index);
+
+ if (reject)
+ {
+ verbosedebugf("SocketDataReady ignored a packet from %#a to %#a on interface %s/%d expecting %#a/%s/%d/%d",
+ &senderAddr, &destAddr, packetInfo.ipi_ifname, packetInfo.ipi_ifindex,
+ &intf->coreIntf.ip, intf->intfName, intf->index, skt);
+ packetLen = -1;
+ num_pkts_rejected++;
+ if (num_pkts_rejected > (num_pkts_accepted + 1) * (num_registered_interfaces + 1) * 2)
+ {
+ fprintf(stderr,
+ "*** WARNING: Received %d packets; Accepted %d packets; Rejected %d packets because of interface mismatch\n",
+ num_pkts_accepted + num_pkts_rejected, num_pkts_accepted, num_pkts_rejected);
+ num_pkts_accepted = 0;
+ num_pkts_rejected = 0;
+ }
+ }
+ else
+ {
+ verbosedebugf("SocketDataReady got a packet from %#a to %#a on interface %#a/%s/%d/%d",
+ &senderAddr, &destAddr, &intf->coreIntf.ip, intf->intfName, intf->index, skt);
+ num_pkts_accepted++;
+ }
+ }
+ }
+
+ if (packetLen >= 0)
+ mDNSCoreReceive(m, &packet, (mDNSu8 *)&packet + packetLen,
+ &senderAddr, senderPort, &destAddr, MulticastDNSPort, InterfaceID);
+ }
+
+mDNSexport TCPSocket *mDNSPlatformTCPSocket(mDNS * const m, TCPSocketFlags flags, mDNSIPPort * port)
+ {
+ (void)m; // Unused
+ (void)flags; // Unused
+ (void)port; // Unused
+ return NULL;
+ }
+
+mDNSexport TCPSocket *mDNSPlatformTCPAccept(TCPSocketFlags flags, int sd)
+ {
+ (void)flags; // Unused
+ (void)sd; // Unused
+ return NULL;
+ }
+
+mDNSexport int mDNSPlatformTCPGetFD(TCPSocket *sock)
+ {
+ (void)sock; // Unused
+ return -1;
+ }
+
+mDNSexport mStatus mDNSPlatformTCPConnect(TCPSocket *sock, const mDNSAddr *dst, mDNSOpaque16 dstport, domainname *hostname, mDNSInterfaceID InterfaceID,
+ TCPConnectionCallback callback, void *context)
+ {
+ (void)sock; // Unused
+ (void)dst; // Unused
+ (void)dstport; // Unused
+ (void)hostname; // Unused
+ (void)InterfaceID; // Unused
+ (void)callback; // Unused
+ (void)context; // Unused
+ return(mStatus_UnsupportedErr);
+ }
+
+mDNSexport void mDNSPlatformTCPCloseConnection(TCPSocket *sock)
+ {
+ (void)sock; // Unused
+ }
+
+mDNSexport long mDNSPlatformReadTCP(TCPSocket *sock, void *buf, unsigned long buflen, mDNSBool * closed)
+ {
+ (void)sock; // Unused
+ (void)buf; // Unused
+ (void)buflen; // Unused
+ (void)closed; // Unused
+ return 0;
+ }
+
+mDNSexport long mDNSPlatformWriteTCP(TCPSocket *sock, const char *msg, unsigned long len)
+ {
+ (void)sock; // Unused
+ (void)msg; // Unused
+ (void)len; // Unused
+ return 0;
+ }
+
+mDNSexport UDPSocket *mDNSPlatformUDPSocket(mDNS * const m, mDNSIPPort port)
+ {
+ (void)m; // Unused
+ (void)port; // Unused
+ return NULL;
+ }
+
+mDNSexport void mDNSPlatformUDPClose(UDPSocket *sock)
+ {
+ (void)sock; // Unused
+ }
+
+mDNSexport void mDNSPlatformUpdateProxyList(mDNS *const m, const mDNSInterfaceID InterfaceID)
+ {
+ (void)m; // Unused
+ (void)InterfaceID; // Unused
+ }
+
+mDNSexport void mDNSPlatformSendRawPacket(const void *const msg, const mDNSu8 *const end, mDNSInterfaceID InterfaceID)
+ {
+ (void)msg; // Unused
+ (void)end; // Unused
+ (void)InterfaceID; // Unused
+ }
+
+mDNSexport void mDNSPlatformSetLocalAddressCacheEntry(mDNS *const m, const mDNSAddr *const tpa, const mDNSEthAddr *const tha, mDNSInterfaceID InterfaceID)
+ {
+ (void)m; // Unused
+ (void)tpa; // Unused
+ (void)tha; // Unused
+ (void)InterfaceID; // Unused
+ }
+
+mDNSexport mStatus mDNSPlatformTLSSetupCerts(void)
+ {
+ return(mStatus_UnsupportedErr);
+ }
+
+mDNSexport void mDNSPlatformTLSTearDownCerts(void)
+ {
+ }
+
+mDNSexport void mDNSPlatformSetAllowSleep(mDNS *const m, mDNSBool allowSleep, const char *reason)
+ {
+ (void) m;
+ (void) allowSleep;
+ (void) reason;
+ }
+
+#if COMPILER_LIKES_PRAGMA_MARK
+#pragma mark -
+#pragma mark - /etc/hosts support
+#endif
+
+mDNSexport void FreeEtcHosts(mDNS *const m, AuthRecord *const rr, mStatus result)
+ {
+ (void)m; // unused
+ (void)rr;
+ (void)result;
+ }
+
+
+#if COMPILER_LIKES_PRAGMA_MARK
+#pragma mark ***** DDNS Config Platform Functions
+#endif
+
+mDNSexport void mDNSPlatformSetDNSConfig(mDNS *const m, mDNSBool setservers, mDNSBool setsearch, domainname *const fqdn, DNameListElem **RegDomains, DNameListElem **BrowseDomains)
+ {
+ (void) m;
+ (void) setservers;
+ (void) fqdn;
+ (void) setsearch;
+ (void) RegDomains;
+ (void) BrowseDomains;
+ }
+
+mDNSexport mStatus mDNSPlatformGetPrimaryInterface(mDNS * const m, mDNSAddr * v4, mDNSAddr * v6, mDNSAddr * router)
+ {
+ (void) m;
+ (void) v4;
+ (void) v6;
+ (void) router;
+
+ return mStatus_UnsupportedErr;
+ }
+
+mDNSexport void mDNSPlatformDynDNSHostNameStatusChanged(const domainname *const dname, const mStatus status)
+ {
+ (void) dname;
+ (void) status;
+ }
+
+#if COMPILER_LIKES_PRAGMA_MARK
+#pragma mark ***** Init and Term
+#endif
+
+// This gets the current hostname, truncating it at the first dot if necessary
+mDNSlocal void GetUserSpecifiedRFC1034ComputerName(domainlabel *const namelabel)
+ {
+ int len = 0;
+ gethostname((char *)(&namelabel->c[1]), MAX_DOMAIN_LABEL);
+ while (len < MAX_DOMAIN_LABEL && namelabel->c[len+1] && namelabel->c[len+1] != '.') len++;
+ namelabel->c[0] = len;
+ }
+
+// On OS X this gets the text of the field labelled "Computer Name" in the Sharing Prefs Control Panel
+// Other platforms can either get the information from the appropriate place,
+// or they can alternatively just require all registering services to provide an explicit name
+mDNSlocal void GetUserSpecifiedFriendlyComputerName(domainlabel *const namelabel)
+ {
+ // On Unix we have no better name than the host name, so we just use that.
+ GetUserSpecifiedRFC1034ComputerName(namelabel);
+ }
+
+mDNSexport int ParseDNSServers(mDNS *m, const char *filePath)
+ {
+ char line[256];
+ char nameserver[16];
+ char keyword[10];
+ int numOfServers = 0;
+ FILE *fp = fopen(filePath, "r");
+ if (fp == NULL) return -1;
+ while (fgets(line,sizeof(line),fp))
+ {
+ struct in_addr ina;
+ line[255]='\0'; // just to be safe
+ if (sscanf(line,"%10s %15s", keyword, nameserver) != 2) continue; // it will skip whitespaces
+ if (strncasecmp(keyword,"nameserver",10)) continue;
+ if (inet_aton(nameserver, (struct in_addr *)&ina) != 0)
+ {
+ mDNSAddr DNSAddr;
+ DNSAddr.type = mDNSAddrType_IPv4;
+ DNSAddr.ip.v4.NotAnInteger = ina.s_addr;
+ mDNS_AddDNSServer(m, NULL, mDNSInterface_Any, &DNSAddr, UnicastDNSPort, mDNSfalse, 0);
+ numOfServers++;
+ }
+ }
+ return (numOfServers > 0) ? 0 : -1;
+ }
+
+// Searches the interface list looking for the named interface.
+// Returns a pointer to if it found, or NULL otherwise.
+mDNSlocal PosixNetworkInterface *SearchForInterfaceByName(mDNS *const m, const char *intfName)
+ {
+ PosixNetworkInterface *intf;
+
+ assert(m != NULL);
+ assert(intfName != NULL);
+
+ intf = (PosixNetworkInterface*)(m->HostInterfaces);
+ while ((intf != NULL) && (strcmp(intf->intfName, intfName) != 0))
+ intf = (PosixNetworkInterface *)(intf->coreIntf.next);
+
+ return intf;
+ }
+
+mDNSexport mDNSInterfaceID mDNSPlatformInterfaceIDfromInterfaceIndex(mDNS *const m, mDNSu32 index)
+ {
+ PosixNetworkInterface *intf;
+
+ assert(m != NULL);
+
+ if (index == kDNSServiceInterfaceIndexLocalOnly) return(mDNSInterface_LocalOnly);
+ if (index == kDNSServiceInterfaceIndexP2P ) return(mDNSInterface_P2P);
+ if (index == kDNSServiceInterfaceIndexAny ) return(mDNSInterface_Any);
+
+ intf = (PosixNetworkInterface*)(m->HostInterfaces);
+ while ((intf != NULL) && (mDNSu32) intf->index != index)
+ intf = (PosixNetworkInterface *)(intf->coreIntf.next);
+
+ return (mDNSInterfaceID) intf;
+ }
+
+mDNSexport mDNSu32 mDNSPlatformInterfaceIndexfromInterfaceID(mDNS *const m, mDNSInterfaceID id, mDNSBool suppressNetworkChange)
+ {
+ PosixNetworkInterface *intf;
+ (void) suppressNetworkChange; // Unused
+
+ assert(m != NULL);
+
+ if (id == mDNSInterface_LocalOnly) return(kDNSServiceInterfaceIndexLocalOnly);
+ if (id == mDNSInterface_P2P ) return(kDNSServiceInterfaceIndexP2P);
+ if (id == mDNSInterface_Any ) return(kDNSServiceInterfaceIndexAny);
+
+ intf = (PosixNetworkInterface*)(m->HostInterfaces);
+ while ((intf != NULL) && (mDNSInterfaceID) intf != id)
+ intf = (PosixNetworkInterface *)(intf->coreIntf.next);
+
+ return intf ? intf->index : 0;
+ }
+
+// Frees the specified PosixNetworkInterface structure. The underlying
+// interface must have already been deregistered with the mDNS core.
+mDNSlocal void FreePosixNetworkInterface(PosixNetworkInterface *intf)
+ {
+ assert(intf != NULL);
+ if (intf->intfName != NULL) free((void *)intf->intfName);
+ if (intf->multicastSocket4 != -1) assert(close(intf->multicastSocket4) == 0);
+#if HAVE_IPV6
+ if (intf->multicastSocket6 != -1) assert(close(intf->multicastSocket6) == 0);
+#endif
+ free(intf);
+ }
+
+// Grab the first interface, deregister it, free it, and repeat until done.
+mDNSlocal void ClearInterfaceList(mDNS *const m)
+ {
+ assert(m != NULL);
+
+ while (m->HostInterfaces)
+ {
+ PosixNetworkInterface *intf = (PosixNetworkInterface*)(m->HostInterfaces);
+ mDNS_DeregisterInterface(m, &intf->coreIntf, mDNSfalse);
+ if (gMDNSPlatformPosixVerboseLevel > 0) fprintf(stderr, "Deregistered interface %s\n", intf->intfName);
+ FreePosixNetworkInterface(intf);
+ }
+ num_registered_interfaces = 0;
+ num_pkts_accepted = 0;
+ num_pkts_rejected = 0;
+ }
+
+// Sets up a send/receive socket.
+// If mDNSIPPort port is non-zero, then it's a multicast socket on the specified interface
+// If mDNSIPPort port is zero, then it's a randomly assigned port number, used for sending unicast queries
+mDNSlocal 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;
+ const mDNSBool JoinMulticastGroup = (port.NotAnInteger != 0);
+
+ (void) interfaceIndex; // This parameter unused on plaforms that don't have IPv6
+ 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);
+#if HAVE_IPV6
+ 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((intfAddr->sa_family == AF_INET) ? "socket AF_INET" : "socket AF_INET6"); }
+
+ // ... with a shared UDP port, if it's for multicast receiving
+ if (err == 0 && port.NotAnInteger)
+ {
+ #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
+ }
+ #if defined(IP_RECVTTL) // Linux
+ if (err == 0)
+ {
+ setsockopt(*sktPtr, IPPROTO_IP, IP_RECVTTL, &kOn, sizeof(kOn));
+ // We no longer depend on being able to get the received TTL, so don't worry if the option fails
+ }
+ #endif
+
+ // Add multicast group membership on this interface
+ if (err == 0 && JoinMulticastGroup)
+ {
+ imr.imr_multiaddr.s_addr = AllDNSLinkGroup_v4.ip.v4.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 && JoinMulticastGroup)
+ {
+ 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)
+
+#if HAVE_IPV6
+ else if (intfAddr->sa_family == AF_INET6)
+ {
+ struct ipv6_mreq imr6;
+ struct sockaddr_in6 bindAddr6;
+ #if defined(IPV6_PKTINFO)
+ if (err == 0)
+ {
+ err = setsockopt(*sktPtr, IPPROTO_IPV6, IPV6_2292_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
+ #if defined(IPV6_HOPLIMIT)
+ if (err == 0)
+ {
+ err = setsockopt(*sktPtr, IPPROTO_IPV6, IPV6_2292_HOPLIMIT, &kOn, sizeof(kOn));
+ if (err < 0) { err = errno; perror("setsockopt - IPV6_HOPLIMIT"); }
+ }
+ #endif
+
+ // Add multicast group membership on this interface
+ if (err == 0 && JoinMulticastGroup)
+ {
+ imr6.ipv6mr_multiaddr = *(const struct in6_addr*)&AllDNSLinkGroup_v6.ip.v6;
+ imr6.ipv6mr_interface = interfaceIndex;
+ //LogMsg("Joining %.16a on %d", &imr6.ipv6mr_multiaddr, imr6.ipv6mr_interface);
+ 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 && JoinMulticastGroup)
+ {
+ 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));
+#ifndef NOT_HAVE_SA_LEN
+ bindAddr6.sin6_len = sizeof(bindAddr6);
+#endif
+ bindAddr6.sin6_family = AF_INET6;
+ bindAddr6.sin6_port = port.NotAnInteger;
+ bindAddr6.sin6_flowinfo = 0;
+ bindAddr6.sin6_addr = in6addr_any; // 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;
+ }
+
+// Creates a PosixNetworkInterface for the interface whose IP address is
+// intfAddr and whose name is intfName and registers it with mDNS core.
+mDNSlocal int SetupOneInterface(mDNS *const m, struct sockaddr *intfAddr, struct sockaddr *intfMask, const char *intfName, int intfIndex)
+ {
+ int err = 0;
+ PosixNetworkInterface *intf;
+ PosixNetworkInterface *alias = NULL;
+
+ assert(m != NULL);
+ assert(intfAddr != NULL);
+ assert(intfName != NULL);
+ assert(intfMask != NULL);
+
+ // Allocate the interface structure itself.
+ intf = (PosixNetworkInterface*)malloc(sizeof(*intf));
+ if (intf == NULL) { assert(0); err = ENOMEM; }
+
+ // And make a copy of the intfName.
+ if (err == 0)
+ {
+ intf->intfName = strdup(intfName);
+ if (intf->intfName == NULL) { assert(0); err = ENOMEM; }
+ }
+
+ if (err == 0)
+ {
+ // Set up the fields required by the mDNS core.
+ SockAddrTomDNSAddr(intfAddr, &intf->coreIntf.ip, NULL);
+ SockAddrTomDNSAddr(intfMask, &intf->coreIntf.mask, NULL);
+
+ //LogMsg("SetupOneInterface: %#a %#a", &intf->coreIntf.ip, &intf->coreIntf.mask);
+ strncpy(intf->coreIntf.ifname, intfName, sizeof(intf->coreIntf.ifname));
+ intf->coreIntf.ifname[sizeof(intf->coreIntf.ifname)-1] = 0;
+ intf->coreIntf.Advertise = m->AdvertiseLocalAddresses;
+ intf->coreIntf.McastTxRx = mDNStrue;
+
+ // Set up the extra fields in PosixNetworkInterface.
+ assert(intf->intfName != NULL); // intf->intfName already set up above
+ intf->index = intfIndex;
+ intf->multicastSocket4 = -1;
+#if HAVE_IPV6
+ intf->multicastSocket6 = -1;
+#endif
+ alias = SearchForInterfaceByName(m, intf->intfName);
+ if (alias == NULL) alias = intf;
+ intf->coreIntf.InterfaceID = (mDNSInterfaceID)alias;
+
+ if (alias != intf)
+ debugf("SetupOneInterface: %s %#a is an alias of %#a", intfName, &intf->coreIntf.ip, &alias->coreIntf.ip);
+ }
+
+ // Set up the multicast socket
+ if (err == 0)
+ {
+ if (alias->multicastSocket4 == -1 && intfAddr->sa_family == AF_INET)
+ err = SetupSocket(intfAddr, MulticastDNSPort, intf->index, &alias->multicastSocket4);
+#if HAVE_IPV6
+ else if (alias->multicastSocket6 == -1 && intfAddr->sa_family == AF_INET6)
+ err = SetupSocket(intfAddr, MulticastDNSPort, intf->index, &alias->multicastSocket6);
+#endif
+ }
+
+ // The interface is all ready to go, let's register it with the mDNS core.
+ if (err == 0)
+ err = mDNS_RegisterInterface(m, &intf->coreIntf, mDNSfalse);
+
+ // Clean up.
+ if (err == 0)
+ {
+ num_registered_interfaces++;
+ debugf("SetupOneInterface: %s %#a Registered", intf->intfName, &intf->coreIntf.ip);
+ if (gMDNSPlatformPosixVerboseLevel > 0)
+ fprintf(stderr, "Registered interface %s\n", intf->intfName);
+ }
+ else
+ {
+ // Use intfName instead of intf->intfName in the next line to avoid dereferencing NULL.
+ debugf("SetupOneInterface: %s %#a failed to register %d", intfName, &intf->coreIntf.ip, err);
+ if (intf) { FreePosixNetworkInterface(intf); intf = NULL; }
+ }
+
+ assert((err == 0) == (intf != NULL));
+
+ return err;
+ }
+
+// Call get_ifi_info() to obtain a list of active interfaces and call SetupOneInterface() on each one.
+mDNSlocal int SetupInterfaceList(mDNS *const m)
+ {
+ mDNSBool foundav4 = mDNSfalse;
+ int err = 0;
+ struct ifi_info *intfList = get_ifi_info(AF_INET, mDNStrue);
+ struct ifi_info *firstLoopback = NULL;
+
+ assert(m != NULL);
+ debugf("SetupInterfaceList");
+
+ if (intfList == NULL) err = ENOENT;
+
+#if HAVE_IPV6
+ if (err == 0) /* Link the IPv6 list to the end of the IPv4 list */
+ {
+ struct ifi_info **p = &intfList;
+ while (*p) p = &(*p)->ifi_next;
+ *p = get_ifi_info(AF_INET6, mDNStrue);
+ }
+#endif
+
+ if (err == 0)
+ {
+ struct ifi_info *i = intfList;
+ while (i)
+ {
+ if ( ((i->ifi_addr->sa_family == AF_INET)
+#if HAVE_IPV6
+ || (i->ifi_addr->sa_family == AF_INET6)
+#endif
+ ) && (i->ifi_flags & IFF_UP) && !(i->ifi_flags & IFF_POINTOPOINT))
+ {
+ if (i->ifi_flags & IFF_LOOPBACK)
+ {
+ if (firstLoopback == NULL)
+ firstLoopback = i;
+ }
+ else
+ {
+ if (SetupOneInterface(m, i->ifi_addr, i->ifi_netmask, i->ifi_name, i->ifi_index) == 0)
+ if (i->ifi_addr->sa_family == AF_INET)
+ foundav4 = mDNStrue;
+ }
+ }
+ i = i->ifi_next;
+ }
+
+ // If we found no normal interfaces but we did find a loopback interface, register the
+ // loopback interface. This allows self-discovery if no interfaces are configured.
+ // Temporary workaround: Multicast loopback on IPv6 interfaces appears not to work.
+ // In the interim, we skip loopback interface only if we found at least one v4 interface to use
+ // if ((m->HostInterfaces == NULL) && (firstLoopback != NULL))
+ if (!foundav4 && firstLoopback)
+ (void) SetupOneInterface(m, firstLoopback->ifi_addr, firstLoopback->ifi_netmask, firstLoopback->ifi_name, firstLoopback->ifi_index);
+ }
+
+ // Clean up.
+ if (intfList != NULL) free_ifi_info(intfList);
+ return err;
+ }
+
+#if USES_NETLINK
+
+// See <http://www.faqs.org/rfcs/rfc3549.html> for a description of NetLink
+
+// Open a socket that will receive interface change notifications
+mDNSlocal mStatus OpenIfNotifySocket(int *pFD)
+ {
+ mStatus err = mStatus_NoError;
+ struct sockaddr_nl snl;
+ int sock;
+ int ret;
+
+ sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
+ if (sock < 0)
+ return errno;
+
+ // Configure read to be non-blocking because inbound msg size is not known in advance
+ (void) fcntl(sock, F_SETFL, O_NONBLOCK);
+
+ /* Subscribe the socket to Link & IP addr notifications. */
+ mDNSPlatformMemZero(&snl, sizeof snl);
+ snl.nl_family = AF_NETLINK;
+ snl.nl_groups = RTMGRP_LINK | RTMGRP_IPV4_IFADDR;
+ ret = bind(sock, (struct sockaddr *) &snl, sizeof snl);
+ if (0 == ret)
+ *pFD = sock;
+ else
+ err = errno;
+
+ return err;
+ }
+
+#if MDNS_DEBUGMSGS
+mDNSlocal void PrintNetLinkMsg(const struct nlmsghdr *pNLMsg)
+ {
+ const char *kNLMsgTypes[] = { "", "NLMSG_NOOP", "NLMSG_ERROR", "NLMSG_DONE", "NLMSG_OVERRUN" };
+ const char *kNLRtMsgTypes[] = { "RTM_NEWLINK", "RTM_DELLINK", "RTM_GETLINK", "RTM_NEWADDR", "RTM_DELADDR", "RTM_GETADDR" };
+
+ printf("nlmsghdr len=%d, type=%s, flags=0x%x\n", pNLMsg->nlmsg_len,
+ pNLMsg->nlmsg_type < RTM_BASE ? kNLMsgTypes[pNLMsg->nlmsg_type] : kNLRtMsgTypes[pNLMsg->nlmsg_type - RTM_BASE],
+ pNLMsg->nlmsg_flags);
+
+ if (RTM_NEWLINK <= pNLMsg->nlmsg_type && pNLMsg->nlmsg_type <= RTM_GETLINK)
+ {
+ struct ifinfomsg *pIfInfo = (struct ifinfomsg*) NLMSG_DATA(pNLMsg);
+ printf("ifinfomsg family=%d, type=%d, index=%d, flags=0x%x, change=0x%x\n", pIfInfo->ifi_family,
+ pIfInfo->ifi_type, pIfInfo->ifi_index, pIfInfo->ifi_flags, pIfInfo->ifi_change);
+
+ }
+ else if (RTM_NEWADDR <= pNLMsg->nlmsg_type && pNLMsg->nlmsg_type <= RTM_GETADDR)
+ {
+ struct ifaddrmsg *pIfAddr = (struct ifaddrmsg*) NLMSG_DATA(pNLMsg);
+ printf("ifaddrmsg family=%d, index=%d, flags=0x%x\n", pIfAddr->ifa_family,
+ pIfAddr->ifa_index, pIfAddr->ifa_flags);
+ }
+ printf("\n");
+ }
+#endif
+
+mDNSlocal mDNSu32 ProcessRoutingNotification(int sd)
+// Read through the messages on sd and if any indicate that any interface records should
+// be torn down and rebuilt, return affected indices as a bitmask. Otherwise return 0.
+ {
+ ssize_t readCount;
+ char buff[4096];
+ struct nlmsghdr *pNLMsg = (struct nlmsghdr*) buff;
+ mDNSu32 result = 0;
+
+ // The structure here is more complex than it really ought to be because,
+ // unfortunately, there's no good way to size a buffer in advance large
+ // enough to hold all pending data and so avoid message fragmentation.
+ // (Note that FIONREAD is not supported on AF_NETLINK.)
+
+ readCount = read(sd, buff, sizeof buff);
+ while (1)
+ {
+ // Make sure we've got an entire nlmsghdr in the buffer, and payload, too.
+ // If not, discard already-processed messages in buffer and read more data.
+ if (((char*) &pNLMsg[1] > (buff + readCount)) || // i.e. *pNLMsg extends off end of buffer
+ ((char*) pNLMsg + pNLMsg->nlmsg_len > (buff + readCount)))
+ {
+ if (buff < (char*) pNLMsg) // we have space to shuffle
+ {
+ // discard processed data
+ readCount -= ((char*) pNLMsg - buff);
+ memmove(buff, pNLMsg, readCount);
+ pNLMsg = (struct nlmsghdr*) buff;
+
+ // read more data
+ readCount += read(sd, buff + readCount, sizeof buff - readCount);
+ continue; // spin around and revalidate with new readCount
+ }
+ else
+ break; // Otherwise message does not fit in buffer
+ }
+
+#if MDNS_DEBUGMSGS
+ PrintNetLinkMsg(pNLMsg);
+#endif
+
+ // Process the NetLink message
+ if (pNLMsg->nlmsg_type == RTM_GETLINK || pNLMsg->nlmsg_type == RTM_NEWLINK)
+ result |= 1 << ((struct ifinfomsg*) NLMSG_DATA(pNLMsg))->ifi_index;
+ else if (pNLMsg->nlmsg_type == RTM_DELADDR || pNLMsg->nlmsg_type == RTM_NEWADDR)
+ result |= 1 << ((struct ifaddrmsg*) NLMSG_DATA(pNLMsg))->ifa_index;
+
+ // Advance pNLMsg to the next message in the buffer
+ if ((pNLMsg->nlmsg_flags & NLM_F_MULTI) != 0 && pNLMsg->nlmsg_type != NLMSG_DONE)
+ {
+ ssize_t len = readCount - ((char*)pNLMsg - buff);
+ pNLMsg = NLMSG_NEXT(pNLMsg, len);
+ }
+ else
+ break; // all done!
+ }
+
+ return result;
+ }
+
+#else // USES_NETLINK
+
+// Open a socket that will receive interface change notifications
+mDNSlocal mStatus OpenIfNotifySocket(int *pFD)
+ {
+ *pFD = socket(AF_ROUTE, SOCK_RAW, 0);
+
+ if (*pFD < 0)
+ return mStatus_UnknownErr;
+
+ // Configure read to be non-blocking because inbound msg size is not known in advance
+ (void) fcntl(*pFD, F_SETFL, O_NONBLOCK);
+
+ return mStatus_NoError;
+ }
+
+#if MDNS_DEBUGMSGS
+mDNSlocal void PrintRoutingSocketMsg(const struct ifa_msghdr *pRSMsg)
+ {
+ const char *kRSMsgTypes[] = { "", "RTM_ADD", "RTM_DELETE", "RTM_CHANGE", "RTM_GET", "RTM_LOSING",
+ "RTM_REDIRECT", "RTM_MISS", "RTM_LOCK", "RTM_OLDADD", "RTM_OLDDEL", "RTM_RESOLVE",
+ "RTM_NEWADDR", "RTM_DELADDR", "RTM_IFINFO", "RTM_NEWMADDR", "RTM_DELMADDR" };
+
+ int index = pRSMsg->ifam_type == RTM_IFINFO ? ((struct if_msghdr*) pRSMsg)->ifm_index : pRSMsg->ifam_index;
+
+ printf("ifa_msghdr len=%d, type=%s, index=%d\n", pRSMsg->ifam_msglen, kRSMsgTypes[pRSMsg->ifam_type], index);
+ }
+#endif
+
+mDNSlocal mDNSu32 ProcessRoutingNotification(int sd)
+// Read through the messages on sd and if any indicate that any interface records should
+// be torn down and rebuilt, return affected indices as a bitmask. Otherwise return 0.
+ {
+ ssize_t readCount;
+ char buff[4096];
+ struct ifa_msghdr *pRSMsg = (struct ifa_msghdr*) buff;
+ mDNSu32 result = 0;
+
+ readCount = read(sd, buff, sizeof buff);
+ if (readCount < (ssize_t) sizeof(struct ifa_msghdr))
+ return mStatus_UnsupportedErr; // cannot decipher message
+
+#if MDNS_DEBUGMSGS
+ PrintRoutingSocketMsg(pRSMsg);
+#endif
+
+ // Process the message
+ if (pRSMsg->ifam_type == RTM_NEWADDR || pRSMsg->ifam_type == RTM_DELADDR ||
+ pRSMsg->ifam_type == RTM_IFINFO)
+ {
+ if (pRSMsg->ifam_type == RTM_IFINFO)
+ result |= 1 << ((struct if_msghdr*) pRSMsg)->ifm_index;
+ else
+ result |= 1 << pRSMsg->ifam_index;
+ }
+
+ return result;
+ }
+
+#endif // USES_NETLINK
+
+// Called when data appears on interface change notification socket
+mDNSlocal void InterfaceChangeCallback(int fd, short filter, void *context)
+ {
+ IfChangeRec *pChgRec = (IfChangeRec*) context;
+ fd_set readFDs;
+ mDNSu32 changedInterfaces = 0;
+ struct timeval zeroTimeout = { 0, 0 };
+
+ (void)fd; // Unused
+ (void)filter; // Unused
+
+ FD_ZERO(&readFDs);
+ FD_SET(pChgRec->NotifySD, &readFDs);
+
+ do
+ {
+ changedInterfaces |= ProcessRoutingNotification(pChgRec->NotifySD);
+ }
+ while (0 < select(pChgRec->NotifySD + 1, &readFDs, (fd_set*) NULL, (fd_set*) NULL, &zeroTimeout));
+
+ // Currently we rebuild the entire interface list whenever any interface change is
+ // detected. If this ever proves to be a performance issue in a multi-homed
+ // configuration, more care should be paid to changedInterfaces.
+ if (changedInterfaces)
+ mDNSPlatformPosixRefreshInterfaceList(pChgRec->mDNS);
+ }
+
+// Register with either a Routing Socket or RtNetLink to listen for interface changes.
+mDNSlocal mStatus WatchForInterfaceChange(mDNS *const m)
+ {
+ mStatus err;
+ IfChangeRec *pChgRec;
+
+ pChgRec = (IfChangeRec*) mDNSPlatformMemAllocate(sizeof *pChgRec);
+ if (pChgRec == NULL)
+ return mStatus_NoMemoryErr;
+
+ pChgRec->mDNS = m;
+ err = OpenIfNotifySocket(&pChgRec->NotifySD);
+ if (err == 0)
+ err = mDNSPosixAddFDToEventLoop(pChgRec->NotifySD, InterfaceChangeCallback, pChgRec);
+
+ return err;
+ }
+
+// Test to see if we're the first client running on UDP port 5353, by trying to bind to 5353 without using SO_REUSEPORT.
+// If we fail, someone else got here first. That's not a big problem; we can share the port for multicast responses --
+// we just need to be aware that we shouldn't expect to successfully receive unicast UDP responses.
+mDNSlocal mDNSBool mDNSPlatformInit_CanReceiveUnicast(void)
+ {
+ int err;
+ int s = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+ struct sockaddr_in s5353;
+ s5353.sin_family = AF_INET;
+ s5353.sin_port = MulticastDNSPort.NotAnInteger;
+ s5353.sin_addr.s_addr = 0;
+ err = bind(s, (struct sockaddr *)&s5353, sizeof(s5353));
+ close(s);
+ if (err) debugf("No unicast UDP responses");
+ else debugf("Unicast UDP responses okay");
+ return(err == 0);
+ }
+
+// mDNS core calls this routine to initialise the platform-specific data.
+mDNSexport mStatus mDNSPlatformInit(mDNS *const m)
+ {
+ int err = 0;
+ struct sockaddr sa;
+ assert(m != NULL);
+
+ if (mDNSPlatformInit_CanReceiveUnicast()) m->CanReceiveUnicastOn5353 = mDNStrue;
+
+ // Tell mDNS core the names of this machine.
+
+ // Set up the nice label
+ m->nicelabel.c[0] = 0;
+ GetUserSpecifiedFriendlyComputerName(&m->nicelabel);
+ if (m->nicelabel.c[0] == 0) MakeDomainLabelFromLiteralString(&m->nicelabel, "Computer");
+
+ // Set up the RFC 1034-compliant label
+ m->hostlabel.c[0] = 0;
+ GetUserSpecifiedRFC1034ComputerName(&m->hostlabel);
+ if (m->hostlabel.c[0] == 0) MakeDomainLabelFromLiteralString(&m->hostlabel, "Computer");
+
+ mDNS_SetFQDN(m);
+
+ sa.sa_family = AF_INET;
+ m->p->unicastSocket4 = -1;
+ if (err == mStatus_NoError) err = SetupSocket(&sa, zeroIPPort, 0, &m->p->unicastSocket4);
+#if HAVE_IPV6
+ sa.sa_family = AF_INET6;
+ m->p->unicastSocket6 = -1;
+ if (err == mStatus_NoError) err = SetupSocket(&sa, zeroIPPort, 0, &m->p->unicastSocket6);
+#endif
+
+ // Tell mDNS core about the network interfaces on this machine.
+ if (err == mStatus_NoError) err = SetupInterfaceList(m);
+
+ // Tell mDNS core about DNS Servers
+ mDNS_Lock(m);
+ if (err == mStatus_NoError) ParseDNSServers(m, uDNS_SERVERS_FILE);
+ mDNS_Unlock(m);
+
+ if (err == mStatus_NoError)
+ {
+ err = WatchForInterfaceChange(m);
+ // Failure to observe interface changes is non-fatal.
+ if (err != mStatus_NoError)
+ {
+ fprintf(stderr, "mDNS(%d) WARNING: Unable to detect interface changes (%d).\n", getpid(), err);
+ err = mStatus_NoError;
+ }
+ }
+
+ // We don't do asynchronous initialization on the Posix platform, so by the time
+ // we get here the setup will already have succeeded or failed. If it succeeded,
+ // we should just call mDNSCoreInitComplete() immediately.
+ if (err == mStatus_NoError)
+ mDNSCoreInitComplete(m, mStatus_NoError);
+
+ return PosixErrorToStatus(err);
+ }
+
+// mDNS core calls this routine to clean up the platform-specific data.
+// In our case all we need to do is to tear down every network interface.
+mDNSexport void mDNSPlatformClose(mDNS *const m)
+ {
+ assert(m != NULL);
+ ClearInterfaceList(m);
+ if (m->p->unicastSocket4 != -1) assert(close(m->p->unicastSocket4) == 0);
+#if HAVE_IPV6
+ if (m->p->unicastSocket6 != -1) assert(close(m->p->unicastSocket6) == 0);
+#endif
+ }
+
+mDNSexport mStatus mDNSPlatformPosixRefreshInterfaceList(mDNS *const m)
+ {
+ int err;
+ ClearInterfaceList(m);
+ err = SetupInterfaceList(m);
+ return PosixErrorToStatus(err);
+ }
+
+#if COMPILER_LIKES_PRAGMA_MARK
+#pragma mark ***** Locking
+#endif
+
+// On the Posix platform, locking is a no-op because we only ever enter
+// mDNS core on the main thread.
+
+// mDNS core calls this routine when it wants to prevent
+// the platform from reentering mDNS core code.
+mDNSexport void mDNSPlatformLock (const mDNS *const m)
+ {
+ (void) m; // Unused
+ }
+
+// mDNS core calls this routine when it release the lock taken by
+// mDNSPlatformLock and allow the platform to reenter mDNS core code.
+mDNSexport void mDNSPlatformUnlock (const mDNS *const m)
+ {
+ (void) m; // Unused
+ }
+
+#if COMPILER_LIKES_PRAGMA_MARK
+#pragma mark ***** Strings
+#endif
+
+// mDNS core calls this routine to copy C strings.
+// On the Posix platform this maps directly to the ANSI C strcpy.
+mDNSexport void mDNSPlatformStrCopy(void *dst, const void *src)
+ {
+ strcpy((char *)dst, (char *)src);
+ }
+
+// mDNS core calls this routine to get the length of a C string.
+// On the Posix platform this maps directly to the ANSI C strlen.
+mDNSexport mDNSu32 mDNSPlatformStrLen (const void *src)
+ {
+ return strlen((char*)src);
+ }
+
+// mDNS core calls this routine to copy memory.
+// On the Posix platform this maps directly to the ANSI C memcpy.
+mDNSexport void mDNSPlatformMemCopy(void *dst, const void *src, mDNSu32 len)
+ {
+ memcpy(dst, src, len);
+ }
+
+// mDNS core calls this routine to test whether blocks of memory are byte-for-byte
+// identical. On the Posix platform this is a simple wrapper around ANSI C memcmp.
+mDNSexport mDNSBool mDNSPlatformMemSame(const void *dst, const void *src, mDNSu32 len)
+ {
+ return memcmp(dst, src, len) == 0;
+ }
+
+// mDNS core calls this routine to clear blocks of memory.
+// On the Posix platform this is a simple wrapper around ANSI C memset.
+mDNSexport void mDNSPlatformMemZero(void *dst, mDNSu32 len)
+ {
+ memset(dst, 0, len);
+ }
+
+mDNSexport void * mDNSPlatformMemAllocate(mDNSu32 len) { return(malloc(len)); }
+mDNSexport void mDNSPlatformMemFree (void *mem) { free(mem); }
+
+mDNSexport mDNSu32 mDNSPlatformRandomSeed(void)
+ {
+ struct timeval tv;
+ gettimeofday(&tv, NULL);
+ return(tv.tv_usec);
+ }
+
+mDNSexport mDNSs32 mDNSPlatformOneSecond = 1024;
+
+mDNSexport mStatus mDNSPlatformTimeInit(void)
+ {
+ // No special setup is required on Posix -- we just use gettimeofday();
+ // This is not really safe, because gettimeofday can go backwards if the user manually changes the date or time
+ // We should find a better way to do this
+ return(mStatus_NoError);
+ }
+
+mDNSexport mDNSs32 mDNSPlatformRawTime()
+ {
+ struct timeval tv;
+ gettimeofday(&tv, NULL);
+ // tv.tv_sec is seconds since 1st January 1970 (GMT, with no adjustment for daylight savings time)
+ // tv.tv_usec is microseconds since the start of this second (i.e. values 0 to 999999)
+ // We use the lower 22 bits of tv.tv_sec for the top 22 bits of our result
+ // and we multiply tv.tv_usec by 16 / 15625 to get a value in the range 0-1023 to go in the bottom 10 bits.
+ // This gives us a proper modular (cyclic) counter that has a resolution of roughly 1ms (actually 1/1024 second)
+ // and correctly cycles every 2^22 seconds (4194304 seconds = approx 48 days).
+ return((tv.tv_sec << 10) | (tv.tv_usec * 16 / 15625));
+ }
+
+mDNSexport mDNSs32 mDNSPlatformUTC(void)
+ {
+ return time(NULL);
+ }
+
+mDNSexport void mDNSPlatformSendWakeupPacket(mDNS *const m, mDNSInterfaceID InterfaceID, char *EthAddr, char *IPAddr, int iteration)
+ {
+ (void) m;
+ (void) InterfaceID;
+ (void) EthAddr;
+ (void) IPAddr;
+ (void) iteration;
+ }
+
+mDNSexport mDNSBool mDNSPlatformValidRecordForInterface(AuthRecord *rr, const NetworkInterfaceInfo *intf)
+ {
+ (void) rr;
+ (void) intf;
+
+ return 1;
+ }
+
+mDNSlocal void mDNSPosixAddToFDSet(int *nfds, fd_set *readfds, int s)
+ {
+ if (*nfds < s + 1) *nfds = s + 1;
+ FD_SET(s, readfds);
+ }
+
+mDNSexport void mDNSPosixGetFDSet(mDNS *m, int *nfds, fd_set *readfds, struct timeval *timeout)
+ {
+ mDNSs32 ticks;
+ struct timeval interval;
+
+ // 1. Call mDNS_Execute() to let mDNSCore do what it needs to do
+ mDNSs32 nextevent = mDNS_Execute(m);
+
+ // 2. Build our list of active file descriptors
+ PosixNetworkInterface *info = (PosixNetworkInterface *)(m->HostInterfaces);
+ if (m->p->unicastSocket4 != -1) mDNSPosixAddToFDSet(nfds, readfds, m->p->unicastSocket4);
+#if HAVE_IPV6
+ if (m->p->unicastSocket6 != -1) mDNSPosixAddToFDSet(nfds, readfds, m->p->unicastSocket6);
+#endif
+ while (info)
+ {
+ if (info->multicastSocket4 != -1) mDNSPosixAddToFDSet(nfds, readfds, info->multicastSocket4);
+#if HAVE_IPV6
+ if (info->multicastSocket6 != -1) mDNSPosixAddToFDSet(nfds, readfds, info->multicastSocket6);
+#endif
+ info = (PosixNetworkInterface *)(info->coreIntf.next);
+ }
+
+ // 3. Calculate the time remaining to the next scheduled event (in struct timeval format)
+ ticks = nextevent - mDNS_TimeNow(m);
+ if (ticks < 1) ticks = 1;
+ interval.tv_sec = ticks >> 10; // The high 22 bits are seconds
+ interval.tv_usec = ((ticks & 0x3FF) * 15625) / 16; // The low 10 bits are 1024ths
+
+ // 4. If client's proposed timeout is more than what we want, then reduce it
+ if (timeout->tv_sec > interval.tv_sec ||
+ (timeout->tv_sec == interval.tv_sec && timeout->tv_usec > interval.tv_usec))
+ *timeout = interval;
+ }
+
+mDNSexport void mDNSPosixProcessFDSet(mDNS *const m, fd_set *readfds)
+ {
+ PosixNetworkInterface *info;
+ assert(m != NULL);
+ assert(readfds != NULL);
+ info = (PosixNetworkInterface *)(m->HostInterfaces);
+
+ if (m->p->unicastSocket4 != -1 && FD_ISSET(m->p->unicastSocket4, readfds))
+ {
+ FD_CLR(m->p->unicastSocket4, readfds);
+ SocketDataReady(m, NULL, m->p->unicastSocket4);
+ }
+#if HAVE_IPV6
+ if (m->p->unicastSocket6 != -1 && FD_ISSET(m->p->unicastSocket6, readfds))
+ {
+ FD_CLR(m->p->unicastSocket6, readfds);
+ SocketDataReady(m, NULL, m->p->unicastSocket6);
+ }
+#endif
+
+ while (info)
+ {
+ if (info->multicastSocket4 != -1 && FD_ISSET(info->multicastSocket4, readfds))
+ {
+ FD_CLR(info->multicastSocket4, readfds);
+ SocketDataReady(m, info, info->multicastSocket4);
+ }
+#if HAVE_IPV6
+ if (info->multicastSocket6 != -1 && FD_ISSET(info->multicastSocket6, readfds))
+ {
+ FD_CLR(info->multicastSocket6, readfds);
+ SocketDataReady(m, info, info->multicastSocket6);
+ }
+#endif
+ info = (PosixNetworkInterface *)(info->coreIntf.next);
+ }
+ }
+
+// update gMaxFD
+mDNSlocal void DetermineMaxEventFD(void)
+ {
+ PosixEventSource *iSource;
+
+ gMaxFD = 0;
+ for (iSource=(PosixEventSource*)gEventSources.Head; iSource; iSource = iSource->Next)
+ if (gMaxFD < iSource->fd)
+ gMaxFD = iSource->fd;
+ }
+
+// Add a file descriptor to the set that mDNSPosixRunEventLoopOnce() listens to.
+mStatus mDNSPosixAddFDToEventLoop(int fd, mDNSPosixEventCallback callback, void *context)
+ {
+ PosixEventSource *newSource;
+
+ if (gEventSources.LinkOffset == 0)
+ InitLinkedList(&gEventSources, offsetof(PosixEventSource, Next));
+
+ if (fd >= (int) FD_SETSIZE || fd < 0)
+ return mStatus_UnsupportedErr;
+ if (callback == NULL)
+ return mStatus_BadParamErr;
+
+ newSource = (PosixEventSource*) malloc(sizeof *newSource);
+ if (NULL == newSource)
+ return mStatus_NoMemoryErr;
+
+ newSource->Callback = callback;
+ newSource->Context = context;
+ newSource->fd = fd;
+
+ AddToTail(&gEventSources, newSource);
+ FD_SET(fd, &gEventFDs);
+
+ DetermineMaxEventFD();
+
+ return mStatus_NoError;
+ }
+
+// Remove a file descriptor from the set that mDNSPosixRunEventLoopOnce() listens to.
+mStatus mDNSPosixRemoveFDFromEventLoop(int fd)
+ {
+ PosixEventSource *iSource;
+
+ for (iSource=(PosixEventSource*)gEventSources.Head; iSource; iSource = iSource->Next)
+ {
+ if (fd == iSource->fd)
+ {
+ FD_CLR(fd, &gEventFDs);
+ RemoveFromList(&gEventSources, iSource);
+ free(iSource);
+ DetermineMaxEventFD();
+ return mStatus_NoError;
+ }
+ }
+ return mStatus_NoSuchNameErr;
+ }
+
+// Simply note the received signal in gEventSignals.
+mDNSlocal void NoteSignal(int signum)
+ {
+ sigaddset(&gEventSignals, signum);
+ }
+
+// Tell the event package to listen for signal and report it in mDNSPosixRunEventLoopOnce().
+mStatus mDNSPosixListenForSignalInEventLoop(int signum)
+ {
+ struct sigaction action;
+ mStatus err;
+
+ mDNSPlatformMemZero(&action, sizeof action); // more portable than member-wise assignment
+ action.sa_handler = NoteSignal;
+ err = sigaction(signum, &action, (struct sigaction*) NULL);
+
+ sigaddset(&gEventSignalSet, signum);
+
+ return err;
+ }
+
+// Tell the event package to stop listening for signal in mDNSPosixRunEventLoopOnce().
+mStatus mDNSPosixIgnoreSignalInEventLoop(int signum)
+ {
+ struct sigaction action;
+ mStatus err;
+
+ mDNSPlatformMemZero(&action, sizeof action); // more portable than member-wise assignment
+ action.sa_handler = SIG_DFL;
+ err = sigaction(signum, &action, (struct sigaction*) NULL);
+
+ sigdelset(&gEventSignalSet, signum);
+
+ return err;
+ }
+
+// Do a single pass through the attendent event sources and dispatch any found to their callbacks.
+// Return as soon as internal timeout expires, or a signal we're listening for is received.
+mStatus mDNSPosixRunEventLoopOnce(mDNS *m, const struct timeval *pTimeout,
+ sigset_t *pSignalsReceived, mDNSBool *pDataDispatched)
+ {
+ fd_set listenFDs = gEventFDs;
+ int fdMax = 0, numReady;
+ struct timeval timeout = *pTimeout;
+
+ // Include the sockets that are listening to the wire in our select() set
+ mDNSPosixGetFDSet(m, &fdMax, &listenFDs, &timeout); // timeout may get modified
+ if (fdMax < gMaxFD)
+ fdMax = gMaxFD;
+
+ numReady = select(fdMax + 1, &listenFDs, (fd_set*) NULL, (fd_set*) NULL, &timeout);
+
+ // If any data appeared, invoke its callback
+ if (numReady > 0)
+ {
+ PosixEventSource *iSource;
+
+ (void) mDNSPosixProcessFDSet(m, &listenFDs); // call this first to process wire data for clients
+
+ for (iSource=(PosixEventSource*)gEventSources.Head; iSource; iSource = iSource->Next)
+ {
+ if (FD_ISSET(iSource->fd, &listenFDs))
+ {
+ iSource->Callback(iSource->fd, 0, iSource->Context);
+ break; // in case callback removed elements from gEventSources
+ }
+ }
+ *pDataDispatched = mDNStrue;
+ }
+ else
+ *pDataDispatched = mDNSfalse;
+
+ (void) sigprocmask(SIG_BLOCK, &gEventSignalSet, (sigset_t*) NULL);
+ *pSignalsReceived = gEventSignals;
+ sigemptyset(&gEventSignals);
+ (void) sigprocmask(SIG_UNBLOCK, &gEventSignalSet, (sigset_t*) NULL);
+
+ return mStatus_NoError;
+ }