MyFavMirrors/owntone-server
1
0
Fork 0
mirror of https://github.com/owntone/owntone-server.git synced 2025-01-09 05:53:23 -05:00
Code Issues Packages Projects Releases Wiki Activity
5c24ad2d02
owntone-server/src/mDNSPosix.c
Ron Pedde 9a133dcbdc Merged win32-branch
2006-02-26 08:46:24 +00:00

1016 lines
44 KiB
C
Raw Blame History

/*
* Copyright (c) 2002-2003 Apple Computer, Inc. All rights reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this
* file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_LICENSE_HEADER_END@
*
* 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.)
Change History (most recent first):
$Log$
Revision 1.6 2006/02/26 08:46:24 rpedde
Merged win32-branch
Revision 1.5.4.1 2006/02/26 08:28:35 rpedde
unix fixes from win32 port
Revision 1.5 2005/01/10 01:07:01 rpedde
Synchronize mDNS to Apples 58.8 drop
Revision 1.25.2.1 2004/04/09 17:57:31 cheshire
Make sure to set the TxAndRx field so that duplicate suppression works correctly
Revision 1.25 2003/10/30 19:25:49 cheshire
Fix signed/unsigned warning on certain compilers
Revision 1.24 2003/08/18 23:12:23 cheshire
<rdar://problem/3382647> mDNSResponder divide by zero in mDNSPlatformTimeNow()
Revision 1.23 2003/08/12 19:56:26 cheshire
Update to APSL 2.0
Revision 1.22 2003/08/06 18:46:15 cheshire
LogMsg() errors are serious -- always report them to stderr, regardless of debugging level
Revision 1.21 2003/08/06 18:20:51 cheshire
Makefile cleanup
Revision 1.20 2003/08/05 23:56:26 cheshire
Update code to compile with the new mDNSCoreReceive() function that requires a TTL
(Right now mDNSPosix.c just reports 255 -- we should fix this)
Revision 1.19 2003/07/19 03:15:16 cheshire
Add generic MemAllocate/MemFree prototypes to mDNSPlatformFunctions.h,
and add the obvious trivial implementations to each platform support layer
Revision 1.18 2003/07/14 18:11:54 cheshire
Fix stricter compiler warnings
Revision 1.17 2003/07/13 01:08:38 cheshire
There's not much point running mDNS over a point-to-point link; exclude those
Revision 1.16 2003/07/02 21:19:59 cheshire
<rdar://problem/3313413> Update copyright notices, etc., in source code comments
Revision 1.15 2003/06/18 05:48:41 cheshire
Fix warnings
Revision 1.14 2003/05/26 03:21:30 cheshire
Tidy up address structure naming:
mDNSIPAddr => mDNSv4Addr (for consistency with mDNSv6Addr)
mDNSAddr.addr.ipv4 => mDNSAddr.ip.v4
mDNSAddr.addr.ipv6 => mDNSAddr.ip.v6
Revision 1.13 2003/05/26 03:01:28 cheshire
<rdar://problem/3268904> sprintf/vsprintf-style functions are unsafe; use snprintf/vsnprintf instead
Revision 1.12 2003/05/21 03:49:18 cheshire
Fix warning
Revision 1.11 2003/05/06 00:00:50 cheshire
<rdar://problem/3248914> Rationalize naming of domainname manipulation functions
Revision 1.10 2003/04/25 01:45:57 cheshire
<rdar://problem/3240002> mDNS_RegisterNoSuchService needs to include a host name
Revision 1.9 2003/03/20 21:10:31 cheshire
Fixes done at IETF 56 to make mDNSProxyResponderPosix run on Solaris
Revision 1.8 2003/03/15 04:40:38 cheshire
Change type called "mDNSOpaqueID" to the more descriptive name "mDNSInterfaceID"
Revision 1.7 2003/03/13 03:46:21 cheshire
Fixes to make the code build on Linux
Revision 1.6 2003/03/08 00:35:56 cheshire
Switched to using new "mDNS_Execute" model (see "mDNSCore/Implementer Notes.txt")
Revision 1.5 2002/12/23 22:13:31 jgraessl
Reviewed by: Stuart Cheshire
Initial IPv6 support for mDNSResponder.
Revision 1.4 2002/09/27 01:47:45 cheshire
Workaround for Linux 2.0 systems that don't have IP_PKTINFO
Revision 1.3 2002/09/21 20:44:53 zarzycki
Added APSL info
Revision 1.2 2002/09/19 21:25:36 cheshire
mDNS_snprintf() doesn't need to be in a separate file
Revision 1.1 2002/09/17 06:24:34 cheshire
First checkin
*/
#include "mDNSClientAPI.h" // Defines the interface provided to the client layer above
#include "mDNSPlatformFunctions.h" // Defines the interface to the supporting layer below
#include "mDNSPosix.h" // Defines the specific types needed to run mDNS on this platform
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/uio.h>
#include <netinet/in.h>
#include "err.h"
#include "mDNSUNP.h"
// ***************************************************************************
// Structures
// PosixNetworkInterface is a record extension of the core NetworkInterfaceInfo
// type that supports extra fields needed by the Posix platform.
//
// IMPORTANT: coreIntf must be the first field in the structure because
// we cast between pointers to the two different types regularly.
typedef struct PosixNetworkInterface PosixNetworkInterface;
struct PosixNetworkInterface
{
NetworkInterfaceInfo coreIntf;
const char * intfName;
PosixNetworkInterface * aliasIntf;
int index;
int multicastSocket;
int multicastSocketv6;
};
// ***************************************************************************
// 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;
// Note, this uses mDNS_vsnprintf instead of standard "vsnprintf", because mDNS_vsnprintf knows
// how to print special data types like IP addresses and length-prefixed domain names
mDNSexport void debugf_(const char *format, ...)
{
unsigned char buffer[512];
va_list ptr;
va_start(ptr,format);
buffer[mDNS_vsnprintf((char *)buffer, sizeof(buffer), format, ptr)] = 0;
va_end(ptr);
DPRINTF(E_INF,L_REND,"%s\n",buffer);
}
mDNSexport void verbosedebugf_(const char *format, ...)
{
unsigned char buffer[512];
va_list ptr;
va_start(ptr,format);
buffer[mDNS_vsnprintf((char *)buffer, sizeof(buffer), format, ptr)] = 0;
va_end(ptr);
DPRINTF(E_DBG,L_REND,"%s\n",buffer);
}
mDNSexport void LogMsg(const char *format, ...)
{
unsigned char buffer[512];
va_list ptr;
va_start(ptr,format);
buffer[mDNS_vsnprintf((char *)buffer, sizeof(buffer), format, ptr)] = 0;
va_end(ptr);
DPRINTF(E_WARN,L_REND,"%s\n",buffer);
}
#define PosixErrorToStatus(errNum) ((errNum) == 0 ? mStatus_NoError : mStatus_UnknownErr)
static 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;
}
#ifdef mDNSIPv6Support
case AF_INET6:
{
struct sockaddr_in6* sin6 = (struct sockaddr_in6*)sa;
assert(sin6->sin6_len == sizeof(*sin6));
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 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);
}
// This routine is called when the main loop detects that data is available on a socket.
static 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;
mDNSBool reject;
assert(m != NULL);
assert(intf != NULL);
assert(skt >= 0);
fromLen = sizeof(from);
flags = 0;
packetLen = recvfrom_flags(skt, &packet, sizeof(packet), &flags, (struct sockaddr *) &from, &fromLen, &packetInfo);
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.ip.v4.NotAnInteger == 0) && (flags & MSG_MCAST) )
{
destAddr.type == senderAddr.type;
if (senderAddr.type == mDNSAddrType_IPv4) destAddr.ip.v4 = AllDNSLinkGroup;
else if (senderAddr.type == mDNSAddrType_IPv6) destAddr.ip.v6 = AllDNSLinkGroupv6;
}
#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 ( 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",
&senderAddr, &destAddr, packetInfo.ipi_ifname, packetInfo.ipi_ifindex,
&intf->coreIntf.ip, intf->intfName, intf->index);
packetLen = -1;
num_pkts_rejected++;
if (num_pkts_rejected > (num_pkts_accepted + 1) * (num_registered_interfaces + 1) * 2)
{
DPRINTF(E_LOG,L_REND,
"*** 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",
&senderAddr, &destAddr, &intf->coreIntf.ip, intf->intfName, intf->index);
num_pkts_accepted++;
}
}
if (packetLen >= 0 && packetLen < (ssize_t)sizeof(DNSMessageHeader))
{
debugf("SocketDataReady packet length (%d) too short", packetLen);
packetLen = -1;
}
if (packetLen >= 0)
mDNSCoreReceive(m, &packet, (mDNSu8 *)&packet + packetLen,
&senderAddr, senderPort, &destAddr, MulticastDNSPort, intf->coreIntf.InterfaceID, 255);
}
#if COMPILER_LIKES_PRAGMA_MARK
#pragma mark ***** Init and Term
#endif
// 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)
{
MakeDomainLabelFromLiteralString(namelabel, "Fill in Default Service Name Here");
}
// 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;
}
// Searches the interface list looking for the named interface.
// Returns a pointer to if it found, or NULL otherwise.
static 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;
}
// Frees the specified PosixNetworkInterface structure. The underlying
// interface must have already been deregistered with the mDNS core.
static void FreePosixNetworkInterface(PosixNetworkInterface *intf)
{
assert(intf != NULL);
if (intf->intfName != NULL) free((void *)intf->intfName);
if (intf->multicastSocket != -1) assert(close(intf->multicastSocket) == 0);
if (intf->multicastSocketv6 != -1) assert(close(intf->multicastSocketv6) == 0);
free(intf);
}
// Grab the first interface, deregister it, free it, and repeat until done.
static void ClearInterfaceList(mDNS *const m)
{
assert(m != NULL);
while (m->HostInterfaces)
{
PosixNetworkInterface *intf = (PosixNetworkInterface*)(m->HostInterfaces);
mDNS_DeregisterInterface(m, &intf->coreIntf);
if (gMDNSPlatformPosixVerboseLevel > 0) DPRINTF(E_LOG,L_REND, "Deregistered interface %s\n", intf->intfName);
FreePosixNetworkInterface(intf);
}
num_registered_interfaces = 0;
num_pkts_accepted = 0;
num_pkts_rejected = 0;
}
// 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;
DPRINTF(E_LOG,L_REND,"bind: %s\n",strerror(errno));
}
}
} // 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;
}
// Creates a PosixNetworkInterface for the interface whose IP address is
// intfAddr and whose name is intfName and registers it with mDNS core.
static int SetupOneInterface(mDNS *const m, struct sockaddr *intfAddr, const char *intfName)
{
int err = 0;
PosixNetworkInterface *intf;
PosixNetworkInterface *alias = NULL;
assert(m != NULL);
assert(intfAddr != NULL);
assert(intfName != NULL);
// Allocate the interface structure itself.
intf = 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);
intf->coreIntf.Advertise = m->AdvertiseLocalAddresses;
intf->coreIntf.TxAndRx = mDNStrue;
// Set up the extra fields in PosixNetworkInterface.
assert(intf->intfName != NULL); // intf->intfName already set up above
intf->index = if_nametoindex(intf->intfName);
intf->multicastSocket = -1;
intf->multicastSocketv6 = -1;
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->multicastSocket == -1 && intfAddr->sa_family == AF_INET)
err = SetupSocket(intfAddr, MulticastDNSPort, intf->index, &alias->multicastSocket);
#ifdef mDNSIPv6Support
else if (alias->multicastSocketv6 == -1 && intfAddr->sa_family == AF_INET6)
err = SetupSocket(intfAddr, MulticastDNSPort, intf->index, &alias->multicastSocketv6);
#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);
// Clean up.
if (err == 0)
{
num_registered_interfaces++;
debugf("SetupOneInterface: %s %#a Registered", intf->intfName, &intf->coreIntf.ip);
if (gMDNSPlatformPosixVerboseLevel > 0)
DPRINTF(E_LOG,L_REND, "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;
}
static 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;
#ifdef mDNSIPv6Support
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)
#ifdef mDNSIPv6Support
|| (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_name) == 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_name);
}
// Clean up.
if (intfList != NULL) free_ifi_info(intfList);
return err;
}
// mDNS core calls this routine to initialise the platform-specific data.
mDNSexport mStatus mDNSPlatformInit(mDNS *const m)
{
int err;
assert(m != NULL);
// 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, "Macintosh");
// Set up the RFC 1034-compliant label
m->hostlabel.c[0] = 0;
GetUserSpecifiedRFC1034ComputerName(&m->hostlabel);
if (m->hostlabel.c[0] == 0) MakeDomainLabelFromLiteralString(&m->hostlabel, "Macintosh");
mDNS_GenerateFQDN(m);
// Tell mDNS core about the network interfaces on this machine.
err = SetupInterfaceList(m);
// 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 == 0)
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);
}
extern 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(const void *src, void *dst)
{
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(const void *src, void *dst, 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 *src, const void *dst, 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 mDNSs32 mDNSPlatformOneSecond = 1024;
mDNSexport mStatus mDNSPlatformTimeInit(mDNSs32 *timenow)
{
// 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
*timenow = mDNSPlatformTimeNow();
return(mStatus_NoError);
}
mDNSexport mDNSs32 mDNSPlatformTimeNow()
{
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 void mDNSPosixGetFDSet(mDNS *const 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);
while (info)
{
if (info->multicastSocket != -1)
{
if (*nfds < info->multicastSocket + 1)
*nfds = info->multicastSocket + 1;
FD_SET(info->multicastSocket, readfds);
}
if (info->multicastSocketv6 != -1)
{
if (*nfds < info->multicastSocketv6 + 1)
*nfds = info->multicastSocketv6 + 1;
FD_SET(info->multicastSocketv6, readfds);
}
info = (PosixNetworkInterface *)(info->coreIntf.next);
}
// 3. Calculate the time remaining to the next scheduled event (in struct timeval format)
ticks = nextevent - mDNSPlatformTimeNow();
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);
while (info)
{
if (info->multicastSocket != -1 && FD_ISSET(info->multicastSocket, readfds))
{
FD_CLR(info->multicastSocket, readfds);
SocketDataReady(m, info, info->multicastSocket);
}
if (info->multicastSocketv6 != -1 && FD_ISSET(info->multicastSocketv6, readfds))
{
FD_CLR(info->multicastSocketv6, readfds);
SocketDataReady(m, info, info->multicastSocketv6);
}
info = (PosixNetworkInterface *)(info->coreIntf.next);
}
}
Reference in New Issue View Git Blame Copy Permalink