/* -*- Mode: C; tab-width: 4 -*-
*
* Copyright (c) 2003-2015 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. Neither the name of Apple Inc. ("Apple") nor the names of its
* contributors may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <errno.h>
#include <stdlib.h>
#include "dnssd_ipc.h"
#if APPLE_OSX_mDNSResponder
#include <mach-o/dyld.h>
#include <uuid/uuid.h>
#include <TargetConditionals.h>
#include "dns_sd_internal.h"
#endif
#if defined(_WIN32)
#define _SSIZE_T
#include <CommonServices.h>
#include <DebugServices.h>
#include <winsock2.h>
#include <ws2tcpip.h>
#include <windows.h>
#include <stdarg.h>
#include <stdio.h>
#define sockaddr_mdns sockaddr_in
#define AF_MDNS AF_INET
// Disable warning: "'type cast' : from data pointer 'void *' to function pointer"
#pragma warning(disable:4055)
// Disable warning: "nonstandard extension, function/data pointer conversion in expression"
#pragma warning(disable:4152)
extern BOOL IsSystemServiceDisabled();
#define sleep(X) Sleep((X) * 1000)
static int g_initWinsock = 0;
#define LOG_WARNING kDebugLevelWarning
#define LOG_INFO kDebugLevelInfo
static void syslog( int priority, const char * message, ...)
{
va_list args;
int len;
char * buffer;
DWORD err = WSAGetLastError();
(void) priority;
va_start( args, message );
len = _vscprintf( message, args ) + 1;
buffer = malloc( len * sizeof(char) );
if ( buffer ) { vsnprintf( buffer, len, message, args ); OutputDebugString( buffer ); free( buffer ); }
WSASetLastError( err );
}
#else
#include <sys/fcntl.h> // For O_RDWR etc.
#include <sys/time.h>
#include <sys/socket.h>
#include <syslog.h>
#define sockaddr_mdns sockaddr_un
#define AF_MDNS AF_LOCAL
#endif
// <rdar://problem/4096913> Specifies how many times we'll try and connect to the server.
#define DNSSD_CLIENT_MAXTRIES 4
// Uncomment the line below to use the old error return mechanism of creating a temporary named socket (e.g. in /var/tmp)
//#define USE_NAMED_ERROR_RETURN_SOCKET 1
// If the UDS client has not received a response from the daemon in 60 secs, it is unlikely to get one
// Note: Timeout of 3 secs should be sufficient in normal scenarios, but 60 secs is chosen as a safeguard since
// some clients may come up before mDNSResponder itself after a BOOT and on rare ocassions IOPM/Keychain/D2D calls
// in mDNSResponder's INIT may take a much longer time to return
#define DNSSD_CLIENT_TIMEOUT 60
#ifndef CTL_PATH_PREFIX
#define CTL_PATH_PREFIX "/var/tmp/dnssd_result_socket."
#endif
typedef struct
{
ipc_msg_hdr ipc_hdr;
DNSServiceFlags cb_flags;
uint32_t cb_interface;
DNSServiceErrorType cb_err;
} CallbackHeader;
typedef struct _DNSServiceRef_t DNSServiceOp;
typedef struct _DNSRecordRef_t DNSRecord;
#if !defined(_WIN32)
typedef struct
{
void *AppCallback; // Client callback function and context
void *AppContext;
} SleepKAContext;
#endif
// client stub callback to process message from server and deliver results to client application
typedef void (*ProcessReplyFn)(DNSServiceOp *const sdr, const CallbackHeader *const cbh, const char *msg, const char *const end);
#define ValidatorBits 0x12345678
#define DNSServiceRefValid(X) (dnssd_SocketValid((X)->sockfd) && (((X)->sockfd ^ (X)->validator) == ValidatorBits))
// When using kDNSServiceFlagsShareConnection, there is one primary _DNSServiceOp_t, and zero or more subordinates
// For the primary, the 'next' field points to the first subordinate, and its 'next' field points to the next, and so on.
// For the primary, the 'primary' field is NULL; for subordinates the 'primary' field points back to the associated primary
//
// _DNS_SD_LIBDISPATCH is defined where libdispatch/GCD is available. This does not mean that the application will use the
// DNSServiceSetDispatchQueue API. Hence any new code guarded with _DNS_SD_LIBDISPATCH should still be backwards compatible.
struct _DNSServiceRef_t
{
DNSServiceOp *next; // For shared connection
DNSServiceOp *primary; // For shared connection
dnssd_sock_t sockfd; // Connected socket between client and daemon
dnssd_sock_t validator; // Used to detect memory corruption, double disposals, etc.
client_context_t uid; // For shared connection requests, each subordinate DNSServiceRef has its own ID,
// unique within the scope of the same shared parent DNSServiceRef
uint32_t op; // request_op_t or reply_op_t
uint32_t max_index; // Largest assigned record index - 0 if no additional records registered
uint32_t logcounter; // Counter used to control number of syslog messages we write
int *moreptr; // Set while DNSServiceProcessResult working on this particular DNSServiceRef
ProcessReplyFn ProcessReply; // Function pointer to the code to handle received messages
void *AppCallback; // Client callback function and context
void *AppContext;
DNSRecord *rec;
#if _DNS_SD_LIBDISPATCH
dispatch_source_t disp_source;
dispatch_queue_t disp_queue;
#endif
void *kacontext;
};
struct _DNSRecordRef_t
{
DNSRecord *recnext;
void *AppContext;
DNSServiceRegisterRecordReply AppCallback;
DNSRecordRef recref;
uint32_t record_index; // index is unique to the ServiceDiscoveryRef
client_context_t uid; // For demultiplexing multiple DNSServiceRegisterRecord calls
DNSServiceOp *sdr;
};
#if !defined(USE_TCP_LOOPBACK)
static void SetUDSPath(struct sockaddr_un *saddr, const char *path)
{
size_t pathLen;
pathLen = strlen(path);
if (pathLen < sizeof(saddr->sun_path))
memcpy(saddr->sun_path, path, pathLen + 1);
else
saddr->sun_path[0] = '\0';
}
#endif
// Write len bytes. Return 0 on success, -1 on error
static int write_all(dnssd_sock_t sd, char *buf, size_t len)
{
// Don't use "MSG_WAITALL"; it returns "Invalid argument" on some Linux versions; use an explicit while() loop instead.
//if (send(sd, buf, len, MSG_WAITALL) != len) return -1;
while (len)
{
ssize_t num_written = send(sd, buf, (long)len, 0);
if (num_written < 0 || (size_t)num_written > len)
{
// Check whether socket has gone defunct,
// otherwise, an error here indicates some OS bug
// or that the mDNSResponder daemon crashed (which should never happen).
#if !defined(__ppc__) && defined(SO_ISDEFUNCT)
int defunct = 0;
socklen_t dlen = sizeof (defunct);
if (getsockopt(sd, SOL_SOCKET, SO_ISDEFUNCT, &defunct, &dlen) < 0)
syslog(LOG_WARNING, "dnssd_clientstub write_all: SO_ISDEFUNCT failed %d %s", dnssd_errno, dnssd_strerror(dnssd_errno));
if (!defunct)
syslog(LOG_WARNING, "dnssd_clientstub write_all(%d) failed %ld/%ld %d %s", sd,
(long)num_written, (long)len,
(num_written < 0) ? dnssd_errno : 0,
(num_written < 0) ? dnssd_strerror(dnssd_errno) : "");
else
syslog(LOG_INFO, "dnssd_clientstub write_all(%d) DEFUNCT", sd);
#else
syslog(LOG_WARNING, "dnssd_clientstub write_all(%d) failed %ld/%ld %d %s", sd,
(long)num_written, (long)len,
(num_written < 0) ? dnssd_errno : 0,
(num_written < 0) ? dnssd_strerror(dnssd_errno) : "");
#endif
return -1;
}
buf += num_written;
len -= num_written;
}
return 0;
}
enum { read_all_success = 0, read_all_fail = -1, read_all_wouldblock = -2 };
// Read len bytes. Return 0 on success, read_all_fail on error, or read_all_wouldblock for
static int read_all(dnssd_sock_t sd, char *buf, int len)
{
// Don't use "MSG_WAITALL"; it returns "Invalid argument" on some Linux versions; use an explicit while() loop instead.
//if (recv(sd, buf, len, MSG_WAITALL) != len) return -1;
while (len)
{
ssize_t num_read = recv(sd, buf, len, 0);
// It is valid to get an interrupted system call error e.g., somebody attaching
// in a debugger, retry without failing
if ((num_read < 0) && (errno == EINTR))
{
syslog(LOG_INFO, "dnssd_clientstub read_all: EINTR continue");
continue;
}
if ((num_read == 0) || (num_read < 0) || (num_read > len))
{
int printWarn = 0;
int defunct = 0;
// Check whether socket has gone defunct,
// otherwise, an error here indicates some OS bug
// or that the mDNSResponder daemon crashed (which should never happen).
#if defined(WIN32)
// <rdar://problem/7481776> Suppress logs for "A non-blocking socket operation
// could not be completed immediately"
if (WSAGetLastError() != WSAEWOULDBLOCK)
printWarn = 1;
#endif
#if !defined(__ppc__) && defined(SO_ISDEFUNCT)
{
socklen_t dlen = sizeof (defunct);
if (getsockopt(sd, SOL_SOCKET, SO_ISDEFUNCT, &defunct, &dlen) < 0)
syslog(LOG_WARNING, "dnssd_clientstub read_all: SO_ISDEFUNCT failed %d %s", dnssd_errno, dnssd_strerror(dnssd_errno));
}
if (!defunct)
printWarn = 1;
#endif
if (printWarn)
syslog(LOG_WARNING, "dnssd_clientstub read_all(%d) failed %ld/%ld %d %s", sd,
(long)num_read, (long)len,
(num_read < 0) ? dnssd_errno : 0,
(num_read < 0) ? dnssd_strerror(dnssd_errno) : "");
else if (defunct)
syslog(LOG_INFO, "dnssd_clientstub read_all(%d) DEFUNCT", sd);
return (num_read < 0 && dnssd_errno == dnssd_EWOULDBLOCK) ? read_all_wouldblock : read_all_fail;
}
buf += num_read;
len -= num_read;
}
return read_all_success;
}
// Returns 1 if more bytes remain to be read on socket descriptor sd, 0 otherwise
static int more_bytes(dnssd_sock_t sd)
{
struct timeval tv = { 0, 0 };
fd_set readfds;
fd_set *fs;
int ret;
#if defined(_WIN32)
fs = &readfds;
FD_ZERO(fs);
FD_SET(sd, fs);
ret = select((int)sd+1, fs, (fd_set*)NULL, (fd_set*)NULL, &tv);
#else
if (sd < FD_SETSIZE)
{
fs = &readfds;
FD_ZERO(fs);
}
else
{
// Compute the number of integers needed for storing "sd". Internally fd_set is stored
// as an array of ints with one bit for each fd and hence we need to compute
// the number of ints needed rather than the number of bytes. If "sd" is 32, we need
// two ints and not just one.
int nfdbits = sizeof (int) * 8;
int nints = (sd/nfdbits) + 1;
fs = (fd_set *)calloc(nints, (size_t)sizeof(int));
if (fs == NULL)
{
syslog(LOG_WARNING, "dnssd_clientstub more_bytes: malloc failed");
return 0;
}
}
FD_SET(sd, fs);
ret = select((int)sd+1, fs, (fd_set*)NULL, (fd_set*)NULL, &tv);
if (fs != &readfds)
free(fs);
#endif
return (ret > 0);
}
// set_waitlimit() implements a timeout using select. It is called from deliver_request() before recv() OR accept()
// to ensure the UDS clients are not blocked in these system calls indefinitely.
// Note: Ideally one should never be blocked here, because it indicates either mDNSResponder daemon is not yet up/hung/
// superbusy/crashed or some other OS bug. For eg: On Windows which suffers from 3rd party software
// (primarily 3rd party firewall software) interfering with proper functioning of the TCP protocol stack it is possible
// the next operation on this socket(recv/accept) is blocked since we depend on TCP to communicate with the system service.
static int set_waitlimit(dnssd_sock_t sock, int timeout)
{
int gDaemonErr = kDNSServiceErr_NoError;
// To prevent stack corruption since select does not work with timeout if fds > FD_SETSIZE(1024)
if (!gDaemonErr && sock < FD_SETSIZE)
{
struct timeval tv;
fd_set set;
FD_ZERO(&set);
FD_SET(sock, &set);
tv.tv_sec = timeout;
tv.tv_usec = 0;
if (!select((int)(sock + 1), &set, NULL, NULL, &tv))
{
// Ideally one should never hit this case: See comments before set_waitlimit()
syslog(LOG_WARNING, "dnssd_clientstub set_waitlimit:_daemon timed out (%d secs) without any response: Socket %d", timeout, sock);
gDaemonErr = kDNSServiceErr_Timeout;
}
}
return gDaemonErr;
}
/* create_hdr
*
* allocate and initialize an ipc message header. Value of len should initially be the
* length of the data, and is set to the value of the data plus the header. data_start
* is set to point to the beginning of the data section. SeparateReturnSocket should be
* non-zero for calls that can't receive an immediate error return value on their primary
* socket, and therefore require a separate return path for the error code result.
* if zero, the path to a control socket is appended at the beginning of the message buffer.
* data_start is set past this string.
*/
static ipc_msg_hdr *create_hdr(uint32_t op, size_t *len, char **data_start, int SeparateReturnSocket, DNSServiceOp *ref)
{
char *msg = NULL;
ipc_msg_hdr *hdr;
int datalen;
#if !defined(USE_TCP_LOOPBACK)
char ctrl_path[64] = ""; // "/var/tmp/dnssd_result_socket.xxxxxxxxxx-xxx-xxxxxx"
#endif
if (SeparateReturnSocket)
{
#if defined(USE_TCP_LOOPBACK)
*len += 2; // Allocate space for two-byte port number
#elif defined(USE_NAMED_ERROR_RETURN_SOCKET)
struct timeval tv;
if (gettimeofday(&tv, NULL) < 0)
{ syslog(LOG_WARNING, "dnssd_clientstub create_hdr: gettimeofday failed %d %s", dnssd_errno, dnssd_strerror(dnssd_errno)); return NULL; }
snprintf(ctrl_path, sizeof(ctrl_path), "%s%d-%.3lx-%.6lu", CTL_PATH_PREFIX, (int)getpid(),
(unsigned long)(tv.tv_sec & 0xFFF), (unsigned long)(tv.tv_usec));
*len += strlen(ctrl_path) + 1;
#else
*len += 1; // Allocate space for single zero byte (empty C string)
#endif
}
datalen = (int) *len;
*len += sizeof(ipc_msg_hdr);
// Write message to buffer
msg = malloc(*len);
if (!msg) { syslog(LOG_WARNING, "dnssd_clientstub create_hdr: malloc failed"); return NULL; }
memset(msg, 0, *len);
hdr = (ipc_msg_hdr *)msg;
hdr->version = VERSION;
hdr->datalen = datalen;
hdr->ipc_flags = 0;
hdr->op = op;
hdr->client_context = ref->uid;
hdr->reg_index = 0;
*data_start = msg + sizeof(ipc_msg_hdr);
#if defined(USE_TCP_LOOPBACK)
// Put dummy data in for the port, since we don't know what it is yet.
// The data will get filled in before we send the message. This happens in deliver_request().
if (SeparateReturnSocket) put_uint16(0, data_start);
#else
if (SeparateReturnSocket) put_string(ctrl_path, data_start);
#endif
return hdr;
}
static void FreeDNSRecords(DNSServiceOp *sdRef)
{
DNSRecord *rec = sdRef->rec;
while (rec)
{
DNSRecord *next = rec->recnext;
free(rec);
rec = next;
}
}
static void FreeDNSServiceOp(DNSServiceOp *x)
{
// We don't use our DNSServiceRefValid macro here because if we're cleaning up after a socket() call failed
// then sockfd could legitimately contain a failing value (e.g. dnssd_InvalidSocket)
if ((x->sockfd ^ x->validator) != ValidatorBits)
{
static DNSServiceOp *op_were_not_going_to_free_but_we_need_to_fool_the_analyzer;
syslog(LOG_WARNING, "dnssd_clientstub attempt to dispose invalid DNSServiceRef %p %08X %08X", x, x->sockfd, x->validator);
op_were_not_going_to_free_but_we_need_to_fool_the_analyzer = x;
}
else
{
x->next = NULL;
x->primary = NULL;
x->sockfd = dnssd_InvalidSocket;
x->validator = 0xDDDDDDDD;
x->op = request_op_none;
x->max_index = 0;
x->logcounter = 0;
x->moreptr = NULL;
x->ProcessReply = NULL;
x->AppCallback = NULL;
x->AppContext = NULL;
#if _DNS_SD_LIBDISPATCH
if (x->disp_source) dispatch_release(x->disp_source);
x->disp_source = NULL;
x->disp_queue = NULL;
#endif
// DNSRecords may have been added to subordinate sdRef e.g., DNSServiceRegister/DNSServiceAddRecord
// or on the main sdRef e.g., DNSServiceCreateConnection/DNSServiceRegisterRecord.
// DNSRecords may have been freed if the application called DNSRemoveRecord.
FreeDNSRecords(x);
if (x->kacontext)
{
free(x->kacontext);
x->kacontext = NULL;
}
free(x);
}
}
// Return a connected service ref (deallocate with DNSServiceRefDeallocate)
static DNSServiceErrorType ConnectToServer(DNSServiceRef *ref, DNSServiceFlags flags, uint32_t op, ProcessReplyFn ProcessReply, void *AppCallback, void *AppContext)
{
int NumTries = 0;
dnssd_sockaddr_t saddr;
DNSServiceOp *sdr;
if (!ref)
{
syslog(LOG_WARNING, "dnssd_clientstub DNSService operation with NULL DNSServiceRef");
return kDNSServiceErr_BadParam;
}
if (flags & kDNSServiceFlagsShareConnection)
{
if (!*ref)
{
syslog(LOG_WARNING, "dnssd_clientstub kDNSServiceFlagsShareConnection used with NULL DNSServiceRef");
return kDNSServiceErr_BadParam;
}
if (!DNSServiceRefValid(*ref) || ((*ref)->op != connection_request && (*ref)->op != connection_delegate_request) || (*ref)->primary)
{
syslog(LOG_WARNING, "dnssd_clientstub kDNSServiceFlagsShareConnection used with invalid DNSServiceRef %p %08X %08X op %d",
(*ref), (*ref)->sockfd, (*ref)->validator, (*ref)->op);
*ref = NULL;
return kDNSServiceErr_BadReference;
}
}
#if defined(_WIN32)
if (!g_initWinsock)
{
WSADATA wsaData;
g_initWinsock = 1;
if (WSAStartup(MAKEWORD(2,2), &wsaData) != 0) { *ref = NULL; return kDNSServiceErr_ServiceNotRunning; }
}
// <rdar://problem/4096913> If the system service is disabled, we only want to try to connect once
if (IsSystemServiceDisabled())
NumTries = DNSSD_CLIENT_MAXTRIES;
#endif
sdr = malloc(sizeof(DNSServiceOp));
if (!sdr)
{
syslog(LOG_WARNING, "dnssd_clientstub ConnectToServer: malloc failed");
*ref = NULL;
return kDNSServiceErr_NoMemory;
}
sdr->next = NULL;
sdr->primary = NULL;
sdr->sockfd = dnssd_InvalidSocket;
sdr->validator = sdr->sockfd ^ ValidatorBits;
sdr->op = op;
sdr->max_index = 0;
sdr->logcounter = 0;
sdr->moreptr = NULL;
sdr->uid.u32[0] = 0;
sdr->uid.u32[1] = 0;
sdr->ProcessReply = ProcessReply;
sdr->AppCallback = AppCallback;
sdr->AppContext = AppContext;
sdr->rec = NULL;
#if _DNS_SD_LIBDISPATCH
sdr->disp_source = NULL;
sdr->disp_queue = NULL;
#endif
sdr->kacontext = NULL;
if (flags & kDNSServiceFlagsShareConnection)
{
DNSServiceOp **p = &(*ref)->next; // Append ourselves to end of primary's list
while (*p)
p = &(*p)->next;
*p = sdr;
// Preincrement counter before we use it -- it helps with debugging if we know the all-zeroes ID should never appear
if (++(*ref)->uid.u32[0] == 0)
++(*ref)->uid.u32[1]; // In parent DNSServiceOp increment UID counter
sdr->primary = *ref; // Set our primary pointer
sdr->sockfd = (*ref)->sockfd; // Inherit primary's socket
sdr->validator = (*ref)->validator;
sdr->uid = (*ref)->uid;
//printf("ConnectToServer sharing socket %d\n", sdr->sockfd);
}
else
{
#ifdef SO_NOSIGPIPE
const unsigned long optval = 1;
#endif
#ifndef USE_TCP_LOOPBACK
char* uds_serverpath = getenv(MDNS_UDS_SERVERPATH_ENVVAR);
if (uds_serverpath == NULL)
uds_serverpath = MDNS_UDS_SERVERPATH;
else if (strlen(uds_serverpath) >= MAX_CTLPATH)
{
uds_serverpath = MDNS_UDS_SERVERPATH;
syslog(LOG_WARNING, "dnssd_clientstub ConnectToServer: using default path since env len is invalid");
}
#endif
*ref = NULL;
sdr->sockfd = socket(AF_DNSSD, SOCK_STREAM, 0);
sdr->validator = sdr->sockfd ^ ValidatorBits;
if (!dnssd_SocketValid(sdr->sockfd))
{
syslog(LOG_WARNING, "dnssd_clientstub ConnectToServer: socket failed %d %s", dnssd_errno, dnssd_strerror(dnssd_errno));
FreeDNSServiceOp(sdr);
return kDNSServiceErr_NoMemory;
}
#ifdef SO_NOSIGPIPE
// Some environments (e.g. OS X) support turning off SIGPIPE for a socket
if (setsockopt(sdr->sockfd, SOL_SOCKET, SO_NOSIGPIPE, &optval, sizeof(optval)) < 0)
syslog(LOG_WARNING, "dnssd_clientstub ConnectToServer: SO_NOSIGPIPE failed %d %s", dnssd_errno, dnssd_strerror(dnssd_errno));
#endif
#if defined(USE_TCP_LOOPBACK)
saddr.sin_family = AF_INET;
saddr.sin_addr.s_addr = inet_addr(MDNS_TCP_SERVERADDR);
saddr.sin_port = htons(MDNS_TCP_SERVERPORT);
#else
saddr.sun_family = AF_LOCAL;
SetUDSPath(&saddr, uds_serverpath);
#if !defined(__ppc__) && defined(SO_DEFUNCTOK)
{
int defunct = 1;
if (setsockopt(sdr->sockfd, SOL_SOCKET, SO_DEFUNCTOK, &defunct, sizeof(defunct)) < 0)
syslog(LOG_WARNING, "dnssd_clientstub ConnectToServer: SO_DEFUNCTOK failed %d %s", dnssd_errno, dnssd_strerror(dnssd_errno));
}
#endif
#endif
while (1)
{
int err = connect(sdr->sockfd, (struct sockaddr *) &saddr, sizeof(saddr));
if (!err)
break; // If we succeeded, return sdr
// If we failed, then it may be because the daemon is still launching.
// This can happen for processes that launch early in the boot process, while the
// daemon is still coming up. Rather than fail here, we wait 1 sec and try again.
// If, after DNSSD_CLIENT_MAXTRIES, we still can't connect to the daemon,
// then we give up and return a failure code.
if (++NumTries < DNSSD_CLIENT_MAXTRIES)
{
syslog(LOG_WARNING, "dnssd_clientstub ConnectToServer: connect()-> No of tries: %d", NumTries);
sleep(1); // Sleep a bit, then try again
}
else
{
#if !defined(USE_TCP_LOOPBACK)
syslog(LOG_WARNING, "dnssd_clientstub ConnectToServer: connect() failed path:%s Socket:%d Err:%d Errno:%d %s",
uds_serverpath, sdr->sockfd, err, dnssd_errno, dnssd_strerror(dnssd_errno));
#endif
dnssd_close(sdr->sockfd);
FreeDNSServiceOp(sdr);
return kDNSServiceErr_ServiceNotRunning;
}
}
//printf("ConnectToServer opened socket %d\n", sdr->sockfd);
}
*ref = sdr;
return kDNSServiceErr_NoError;
}
#define deliver_request_bailout(MSG) \
do { syslog(LOG_WARNING, "dnssd_clientstub deliver_request: %s failed %d (%s)", (MSG), dnssd_errno, dnssd_strerror(dnssd_errno)); goto cleanup; } while(0)
static DNSServiceErrorType deliver_request(ipc_msg_hdr *hdr, DNSServiceOp *sdr)
{
uint32_t datalen;
dnssd_sock_t listenfd = dnssd_InvalidSocket, errsd = dnssd_InvalidSocket;
DNSServiceErrorType err = kDNSServiceErr_Unknown; // Default for the "goto cleanup" cases
int MakeSeparateReturnSocket;
#if defined(USE_TCP_LOOPBACK) || defined(USE_NAMED_ERROR_RETURN_SOCKET)
char *data;
#endif
if (!hdr)
{
syslog(LOG_WARNING, "dnssd_clientstub deliver_request: !hdr");
return kDNSServiceErr_Unknown;
}
datalen = hdr->datalen; // We take a copy here because we're going to convert hdr->datalen to network byte order
#if defined(USE_TCP_LOOPBACK) || defined(USE_NAMED_ERROR_RETURN_SOCKET)
data = (char *)hdr + sizeof(ipc_msg_hdr);
#endif
// Note: need to check hdr->op, not sdr->op.
// hdr->op contains the code for the specific operation we're currently doing, whereas sdr->op
// contains the original parent DNSServiceOp (e.g. for an add_record_request, hdr->op will be
// add_record_request but the parent sdr->op will be connection_request or reg_service_request)
MakeSeparateReturnSocket = (sdr->primary ||
hdr->op == reg_record_request || hdr->op == add_record_request || hdr->op == update_record_request || hdr->op == remove_record_request);
if (!DNSServiceRefValid(sdr))
{
if (hdr)
free(hdr);
syslog(LOG_WARNING, "dnssd_clientstub deliver_request: invalid DNSServiceRef %p %08X %08X", sdr, sdr->sockfd, sdr->validator);
return kDNSServiceErr_BadReference;
}
if (MakeSeparateReturnSocket)
{
#if defined(USE_TCP_LOOPBACK)
{
union { uint16_t s; u_char b[2]; } port;
dnssd_sockaddr_t caddr;
dnssd_socklen_t len = (dnssd_socklen_t) sizeof(caddr);
listenfd = socket(AF_DNSSD, SOCK_STREAM, 0);
if (!dnssd_SocketValid(listenfd)) deliver_request_bailout("TCP socket");
caddr.sin_family = AF_INET;
caddr.sin_port = 0;
caddr.sin_addr.s_addr = inet_addr(MDNS_TCP_SERVERADDR);
if (bind(listenfd, (struct sockaddr*) &caddr, sizeof(caddr)) < 0) deliver_request_bailout("TCP bind");
if (getsockname(listenfd, (struct sockaddr*) &caddr, &len) < 0) deliver_request_bailout("TCP getsockname");
if (listen(listenfd, 1) < 0) deliver_request_bailout("TCP listen");
port.s = caddr.sin_port;
data[0] = port.b[0]; // don't switch the byte order, as the
data[1] = port.b[1]; // daemon expects it in network byte order
}
#elif defined(USE_NAMED_ERROR_RETURN_SOCKET)
{
mode_t mask;
int bindresult;
dnssd_sockaddr_t caddr;
listenfd = socket(AF_DNSSD, SOCK_STREAM, 0);
if (!dnssd_SocketValid(listenfd)) deliver_request_bailout("USE_NAMED_ERROR_RETURN_SOCKET socket");
caddr.sun_family = AF_LOCAL;
// According to Stevens (section 3.2), there is no portable way to
// determine whether sa_len is defined on a particular platform.
#ifndef NOT_HAVE_SA_LEN
caddr.sun_len = sizeof(struct sockaddr_un);
#endif
SetUDSPath(&caddr, data);
mask = umask(0);
bindresult = bind(listenfd, (struct sockaddr *)&caddr, sizeof(caddr));
umask(mask);
if (bindresult < 0) deliver_request_bailout("USE_NAMED_ERROR_RETURN_SOCKET bind");
if (listen(listenfd, 1) < 0) deliver_request_bailout("USE_NAMED_ERROR_RETURN_SOCKET listen");
}
#else
{
dnssd_sock_t sp[2];
if (socketpair(AF_DNSSD, SOCK_STREAM, 0, sp) < 0) deliver_request_bailout("socketpair");
else
{
errsd = sp[0]; // We'll read our four-byte error code from sp[0]
listenfd = sp[1]; // We'll send sp[1] to the daemon
#if !defined(__ppc__) && defined(SO_DEFUNCTOK)
{
int defunct = 1;
if (setsockopt(errsd, SOL_SOCKET, SO_DEFUNCTOK, &defunct, sizeof(defunct)) < 0)
syslog(LOG_WARNING, "dnssd_clientstub ConnectToServer: SO_DEFUNCTOK failed %d %s", dnssd_errno, dnssd_strerror(dnssd_errno));
}
#endif
}
}
#endif
}
#if !defined(USE_TCP_LOOPBACK) && !defined(USE_NAMED_ERROR_RETURN_SOCKET)
// If we're going to make a separate error return socket, and pass it to the daemon
// using sendmsg, then we'll hold back one data byte to go with it.
// On some versions of Unix (including Leopard) sending a control message without
// any associated data does not work reliably -- e.g. one particular issue we ran
// into is that if the receiving program is in a kqueue loop waiting to be notified
// of the received message, it doesn't get woken up when the control message arrives.
if (MakeSeparateReturnSocket || sdr->op == send_bpf)
datalen--; // Okay to use sdr->op when checking for op == send_bpf
#endif
// At this point, our listening socket is set up and waiting, if necessary, for the daemon to connect back to
ConvertHeaderBytes(hdr);
//syslog(LOG_WARNING, "dnssd_clientstub deliver_request writing %lu bytes", (unsigned long)(datalen + sizeof(ipc_msg_hdr)));
//if (MakeSeparateReturnSocket) syslog(LOG_WARNING, "dnssd_clientstub deliver_request name is %s", data);
#if TEST_SENDING_ONE_BYTE_AT_A_TIME
unsigned int i;
for (i=0; i<datalen + sizeof(ipc_msg_hdr); i++)
{
syslog(LOG_WARNING, "dnssd_clientstub deliver_request writing %d", i);
if (write_all(sdr->sockfd, ((char *)hdr)+i, 1) < 0)
{ syslog(LOG_WARNING, "write_all (byte %u) failed", i); goto cleanup; }
usleep(10000);
}
#else
if (write_all(sdr->sockfd, (char *)hdr, datalen + sizeof(ipc_msg_hdr)) < 0)
{
// write_all already prints an error message if there is an error writing to
// the socket except for DEFUNCT. Logging here is unnecessary and also wrong
// in the case of DEFUNCT sockets
syslog(LOG_INFO, "dnssd_clientstub deliver_request ERROR: write_all(%d, %lu bytes) failed",
sdr->sockfd, (unsigned long)(datalen + sizeof(ipc_msg_hdr)));
goto cleanup;
}
#endif
if (!MakeSeparateReturnSocket)
errsd = sdr->sockfd;
if (MakeSeparateReturnSocket || sdr->op == send_bpf) // Okay to use sdr->op when checking for op == send_bpf
{
#if defined(USE_TCP_LOOPBACK) || defined(USE_NAMED_ERROR_RETURN_SOCKET)
// At this point we may wait in accept for a few milliseconds waiting for the daemon to connect back to us,
// but that's okay -- the daemon should not take more than a few milliseconds to respond.
// set_waitlimit() ensures we do not block indefinitely just in case something is wrong
dnssd_sockaddr_t daddr;
dnssd_socklen_t len = sizeof(daddr);
if ((err = set_waitlimit(listenfd, DNSSD_CLIENT_TIMEOUT)) != kDNSServiceErr_NoError)
goto cleanup;
errsd = accept(listenfd, (struct sockaddr *)&daddr, &len);
if (!dnssd_SocketValid(errsd))
deliver_request_bailout("accept");
#else
struct iovec vec = { ((char *)hdr) + sizeof(ipc_msg_hdr) + datalen, 1 }; // Send the last byte along with the SCM_RIGHTS
struct msghdr msg;
struct cmsghdr *cmsg;
char cbuf[CMSG_SPACE(4 * sizeof(dnssd_sock_t))];
msg.msg_name = 0;
msg.msg_namelen = 0;
msg.msg_iov = &vec;
msg.msg_iovlen = 1;
msg.msg_flags = 0;
if (MakeSeparateReturnSocket || sdr->op == send_bpf) // Okay to use sdr->op when checking for op == send_bpf
{
if (sdr->op == send_bpf)
{
int i;
char p[12]; // Room for "/dev/bpf999" with terminating null
for (i=0; i<100; i++)
{
snprintf(p, sizeof(p), "/dev/bpf%d", i);
listenfd = open(p, O_RDWR, 0);
//if (dnssd_SocketValid(listenfd)) syslog(LOG_WARNING, "Sending fd %d for %s", listenfd, p);
if (!dnssd_SocketValid(listenfd) && dnssd_errno != EBUSY)
syslog(LOG_WARNING, "Error opening %s %d (%s)", p, dnssd_errno, dnssd_strerror(dnssd_errno));
if (dnssd_SocketValid(listenfd) || dnssd_errno != EBUSY) break;
}
}
msg.msg_control = cbuf;
msg.msg_controllen = CMSG_LEN(sizeof(dnssd_sock_t));
cmsg = CMSG_FIRSTHDR(&msg);
cmsg->cmsg_len = CMSG_LEN(sizeof(dnssd_sock_t));
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_type = SCM_RIGHTS;
*((dnssd_sock_t *)CMSG_DATA(cmsg)) = listenfd;
}
#if TEST_KQUEUE_CONTROL_MESSAGE_BUG
sleep(1);
#endif
#if DEBUG_64BIT_SCM_RIGHTS
syslog(LOG_WARNING, "dnssd_clientstub sendmsg read sd=%d write sd=%d %ld %ld %ld/%ld/%ld/%ld",
errsd, listenfd, sizeof(dnssd_sock_t), sizeof(void*),
sizeof(struct cmsghdr) + sizeof(dnssd_sock_t),
CMSG_LEN(sizeof(dnssd_sock_t)), (long)CMSG_SPACE(sizeof(dnssd_sock_t)),
(long)((char*)CMSG_DATA(cmsg) + 4 - cbuf));
#endif // DEBUG_64BIT_SCM_RIGHTS
if (sendmsg(sdr->sockfd, &msg, 0) < 0)
{
syslog(LOG_WARNING, "dnssd_clientstub deliver_request ERROR: sendmsg failed read sd=%d write sd=%d errno %d (%s)",
errsd, listenfd, dnssd_errno, dnssd_strerror(dnssd_errno));
err = kDNSServiceErr_Incompatible;
goto cleanup;
}
#if DEBUG_64BIT_SCM_RIGHTS
syslog(LOG_WARNING, "dnssd_clientstub sendmsg read sd=%d write sd=%d okay", errsd, listenfd);
#endif // DEBUG_64BIT_SCM_RIGHTS
#endif
// Close our end of the socketpair *before* calling read_all() to get the four-byte error code.
// Otherwise, if the daemon closes our socket (or crashes), we will have to wait for a timeout
// in read_all() because the socket is not closed (we still have an open reference to it)
// Note: listenfd is overwritten in the case of send_bpf above and that will be closed here
// for send_bpf operation.
dnssd_close(listenfd);
listenfd = dnssd_InvalidSocket; // Make sure we don't close it a second time in the cleanup handling below
}
// At this point we may wait in read_all for a few milliseconds waiting for the daemon to send us the error code,
// but that's okay -- the daemon should not take more than a few milliseconds to respond.
// set_waitlimit() ensures we do not block indefinitely just in case something is wrong
if (sdr->op == send_bpf) // Okay to use sdr->op when checking for op == send_bpf
err = kDNSServiceErr_NoError;
else if ((err = set_waitlimit(errsd, DNSSD_CLIENT_TIMEOUT)) == kDNSServiceErr_NoError)
{
if (read_all(errsd, (char*)&err, (int)sizeof(err)) < 0)
err = kDNSServiceErr_ServiceNotRunning; // On failure read_all will have written a message to syslog for us
else
err = ntohl(err);
}
//syslog(LOG_WARNING, "dnssd_clientstub deliver_request: retrieved error code %d", err);
cleanup:
if (MakeSeparateReturnSocket)
{
if (dnssd_SocketValid(listenfd)) dnssd_close(listenfd);
if (dnssd_SocketValid(errsd)) dnssd_close(errsd);
#if defined(USE_NAMED_ERROR_RETURN_SOCKET)
// syslog(LOG_WARNING, "dnssd_clientstub deliver_request: removing UDS: %s", data);
if (unlink(data) != 0)
syslog(LOG_WARNING, "dnssd_clientstub WARNING: unlink(\"%s\") failed errno %d (%s)", data, dnssd_errno, dnssd_strerror(dnssd_errno));
// else syslog(LOG_WARNING, "dnssd_clientstub deliver_request: removed UDS: %s", data);
#endif
}
free(hdr);
return err;
}
dnssd_sock_t DNSSD_API DNSServiceRefSockFD(DNSServiceRef sdRef)
{
if (!sdRef) { syslog(LOG_WARNING, "dnssd_clientstub DNSServiceRefSockFD called with NULL DNSServiceRef"); return dnssd_InvalidSocket; }
if (!DNSServiceRefValid(sdRef))
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceRefSockFD called with invalid DNSServiceRef %p %08X %08X",
sdRef, sdRef->sockfd, sdRef->validator);
return dnssd_InvalidSocket;
}
if (sdRef->primary)
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceRefSockFD undefined for kDNSServiceFlagsShareConnection subordinate DNSServiceRef %p", sdRef);
return dnssd_InvalidSocket;
}
return sdRef->sockfd;
}
#if _DNS_SD_LIBDISPATCH
static void CallbackWithError(DNSServiceRef sdRef, DNSServiceErrorType error)
{
DNSServiceOp *sdr = sdRef;
DNSServiceOp *sdrNext;
DNSRecord *rec;
DNSRecord *recnext;
int morebytes;
while (sdr)
{
// We can't touch the sdr after the callback as it can be deallocated in the callback
sdrNext = sdr->next;
morebytes = 1;
sdr->moreptr = &morebytes;
switch (sdr->op)
{
case resolve_request:
if (sdr->AppCallback) ((DNSServiceResolveReply) sdr->AppCallback)(sdr, 0, 0, error, NULL, 0, 0, 0, NULL, sdr->AppContext);
break;
case query_request:
if (sdr->AppCallback) ((DNSServiceQueryRecordReply)sdr->AppCallback)(sdr, 0, 0, error, NULL, 0, 0, 0, NULL, 0, sdr->AppContext);
break;
case addrinfo_request:
if (sdr->AppCallback) ((DNSServiceGetAddrInfoReply)sdr->AppCallback)(sdr, 0, 0, error, NULL, NULL, 0, sdr->AppContext);
break;
case browse_request:
if (sdr->AppCallback) ((DNSServiceBrowseReply) sdr->AppCallback)(sdr, 0, 0, error, NULL, 0, NULL, sdr->AppContext);
break;
case reg_service_request:
if (sdr->AppCallback) ((DNSServiceRegisterReply) sdr->AppCallback)(sdr, 0, error, NULL, 0, NULL, sdr->AppContext);
break;
case enumeration_request:
if (sdr->AppCallback) ((DNSServiceDomainEnumReply) sdr->AppCallback)(sdr, 0, 0, error, NULL, sdr->AppContext);
break;
case connection_request:
case connection_delegate_request:
// This means Register Record, walk the list of DNSRecords to do the callback
rec = sdr->rec;
while (rec)
{
recnext = rec->recnext;
if (rec->AppCallback) ((DNSServiceRegisterRecordReply)rec->AppCallback)(sdr, 0, 0, error, rec->AppContext);
// The Callback can call DNSServiceRefDeallocate which in turn frees sdr and all the records.
// Detect that and return early
if (!morebytes) {syslog(LOG_WARNING, "dnssdclientstub:Record: CallbackwithError morebytes zero"); return;}
rec = recnext;
}
break;
case port_mapping_request:
if (sdr->AppCallback) ((DNSServiceNATPortMappingReply)sdr->AppCallback)(sdr, 0, 0, error, 0, 0, 0, 0, 0, sdr->AppContext);
break;
default:
syslog(LOG_WARNING, "dnssd_clientstub CallbackWithError called with bad op %d", sdr->op);
}
// If DNSServiceRefDeallocate was called in the callback, morebytes will be zero. As the sdRef
// (and its subordinates) have been freed, we should not proceed further. Note that when we
// call the callback with a subordinate sdRef the application can call DNSServiceRefDeallocate
// on the main sdRef and DNSServiceRefDeallocate handles this case by walking all the sdRefs and
// clears the moreptr so that we can terminate here.
//
// If DNSServiceRefDeallocate was not called in the callback, then set moreptr to NULL so that
// we don't access the stack variable after we return from this function.
if (!morebytes) {syslog(LOG_WARNING, "dnssdclientstub:sdRef: CallbackwithError morebytes zero sdr %p", sdr); return;}
else {sdr->moreptr = NULL;}
sdr = sdrNext;
}
}
#endif // _DNS_SD_LIBDISPATCH
// Handle reply from server, calling application client callback. If there is no reply
// from the daemon on the socket contained in sdRef, the call will block.
DNSServiceErrorType DNSSD_API DNSServiceProcessResult(DNSServiceRef sdRef)
{
int morebytes = 0;
if (!sdRef) { syslog(LOG_WARNING, "dnssd_clientstub DNSServiceProcessResult called with NULL DNSServiceRef"); return kDNSServiceErr_BadParam; }
if (!DNSServiceRefValid(sdRef))
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceProcessResult called with invalid DNSServiceRef %p %08X %08X", sdRef, sdRef->sockfd, sdRef->validator);
return kDNSServiceErr_BadReference;
}
if (sdRef->primary)
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceProcessResult undefined for kDNSServiceFlagsShareConnection subordinate DNSServiceRef %p", sdRef);
return kDNSServiceErr_BadReference;
}
if (!sdRef->ProcessReply)
{
static int num_logs = 0;
if (num_logs < 10) syslog(LOG_WARNING, "dnssd_clientstub DNSServiceProcessResult called with DNSServiceRef with no ProcessReply function");
if (num_logs < 1000) num_logs++;else sleep(1);
return kDNSServiceErr_BadReference;
}
do
{
CallbackHeader cbh;
char *data;
// return NoError on EWOULDBLOCK. This will handle the case
// where a non-blocking socket is told there is data, but it was a false positive.
// On error, read_all will write a message to syslog for us, so don't need to duplicate that here
// Note: If we want to properly support using non-blocking sockets in the future
int result = read_all(sdRef->sockfd, (void *)&cbh.ipc_hdr, sizeof(cbh.ipc_hdr));
if (result == read_all_fail)
{
// Set the ProcessReply to NULL before callback as the sdRef can get deallocated
// in the callback.
sdRef->ProcessReply = NULL;
#if _DNS_SD_LIBDISPATCH
// Call the callbacks with an error if using the dispatch API, as DNSServiceProcessResult
// is not called by the application and hence need to communicate the error. Cancel the
// source so that we don't get any more events
// Note: read_all fails if we could not read from the daemon which can happen if the
// daemon dies or the file descriptor is disconnected (defunct).
if (sdRef->disp_source)
{
dispatch_source_cancel(sdRef->disp_source);
dispatch_release(sdRef->disp_source);
sdRef->disp_source = NULL;
CallbackWithError(sdRef, kDNSServiceErr_ServiceNotRunning);
}
#endif
// Don't touch sdRef anymore as it might have been deallocated
return kDNSServiceErr_ServiceNotRunning;
}
else if (result == read_all_wouldblock)
{
if (morebytes && sdRef->logcounter < 100)
{
sdRef->logcounter++;
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceProcessResult error: select indicated data was waiting but read_all returned EWOULDBLOCK");
}
return kDNSServiceErr_NoError;
}
ConvertHeaderBytes(&cbh.ipc_hdr);
if (cbh.ipc_hdr.version != VERSION)
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceProcessResult daemon version %d does not match client version %d", cbh.ipc_hdr.version, VERSION);
sdRef->ProcessReply = NULL;
return kDNSServiceErr_Incompatible;
}
data = malloc(cbh.ipc_hdr.datalen);
if (!data) return kDNSServiceErr_NoMemory;
if (read_all(sdRef->sockfd, data, cbh.ipc_hdr.datalen) < 0) // On error, read_all will write a message to syslog for us
{
// Set the ProcessReply to NULL before callback as the sdRef can get deallocated
// in the callback.
sdRef->ProcessReply = NULL;
#if _DNS_SD_LIBDISPATCH
// Call the callbacks with an error if using the dispatch API, as DNSServiceProcessResult
// is not called by the application and hence need to communicate the error. Cancel the
// source so that we don't get any more events
if (sdRef->disp_source)
{
dispatch_source_cancel(sdRef->disp_source);
dispatch_release(sdRef->disp_source);
sdRef->disp_source = NULL;
CallbackWithError(sdRef, kDNSServiceErr_ServiceNotRunning);
}
#endif
// Don't touch sdRef anymore as it might have been deallocated
free(data);
return kDNSServiceErr_ServiceNotRunning;
}
else
{
const char *ptr = data;
cbh.cb_flags = get_flags (&ptr, data + cbh.ipc_hdr.datalen);
cbh.cb_interface = get_uint32 (&ptr, data + cbh.ipc_hdr.datalen);
cbh.cb_err = get_error_code(&ptr, data + cbh.ipc_hdr.datalen);
// CAUTION: We have to handle the case where the client calls DNSServiceRefDeallocate from within the callback function.
// To do this we set moreptr to point to morebytes. If the client does call DNSServiceRefDeallocate(),
// then that routine will clear morebytes for us, and cause us to exit our loop.
morebytes = more_bytes(sdRef->sockfd);
if (morebytes)
{
cbh.cb_flags |= kDNSServiceFlagsMoreComing;
sdRef->moreptr = &morebytes;
}
if (ptr) sdRef->ProcessReply(sdRef, &cbh, ptr, data + cbh.ipc_hdr.datalen);
// Careful code here:
// If morebytes is non-zero, that means we set sdRef->moreptr above, and the operation was not
// cancelled out from under us, so now we need to clear sdRef->moreptr so we don't leave a stray
// dangling pointer pointing to a long-gone stack variable.
// If morebytes is zero, then one of two thing happened:
// (a) morebytes was 0 above, so we didn't set sdRef->moreptr, so we don't need to clear it
// (b) morebytes was 1 above, and we set sdRef->moreptr, but the operation was cancelled (with DNSServiceRefDeallocate()),
// so we MUST NOT try to dereference our stale sdRef pointer.
if (morebytes) sdRef->moreptr = NULL;
}
free(data);
} while (morebytes);
return kDNSServiceErr_NoError;
}
void DNSSD_API DNSServiceRefDeallocate(DNSServiceRef sdRef)
{
if (!sdRef) { syslog(LOG_WARNING, "dnssd_clientstub DNSServiceRefDeallocate called with NULL DNSServiceRef"); return; }
if (!DNSServiceRefValid(sdRef)) // Also verifies dnssd_SocketValid(sdRef->sockfd) for us too
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceRefDeallocate called with invalid DNSServiceRef %p %08X %08X", sdRef, sdRef->sockfd, sdRef->validator);
return;
}
// If we're in the middle of a DNSServiceProcessResult() invocation for this DNSServiceRef, clear its morebytes flag to break it out of its while loop
if (sdRef->moreptr) *(sdRef->moreptr) = 0;
if (sdRef->primary) // If this is a subordinate DNSServiceOp, just send a 'stop' command
{
DNSServiceOp **p = &sdRef->primary->next;
while (*p && *p != sdRef) p = &(*p)->next;
if (*p)
{
char *ptr;
size_t len = 0;
ipc_msg_hdr *hdr = create_hdr(cancel_request, &len, &ptr, 0, sdRef);
if (hdr)
{
ConvertHeaderBytes(hdr);
write_all(sdRef->sockfd, (char *)hdr, len);
free(hdr);
}
*p = sdRef->next;
FreeDNSServiceOp(sdRef);
}
}
else // else, make sure to terminate all subordinates as well
{
#if _DNS_SD_LIBDISPATCH
// The cancel handler will close the fd if a dispatch source has been set
if (sdRef->disp_source)
{
// By setting the ProcessReply to NULL, we make sure that we never call
// the application callbacks ever, after returning from this function. We
// assume that DNSServiceRefDeallocate is called from the serial queue
// that was passed to DNSServiceSetDispatchQueue. Hence, dispatch_source_cancel
// should cancel all the blocks on the queue and hence there should be no more
// callbacks when we return from this function. Setting ProcessReply to NULL
// provides extra protection.
sdRef->ProcessReply = NULL;
shutdown(sdRef->sockfd, SHUT_WR);
dispatch_source_cancel(sdRef->disp_source);
dispatch_release(sdRef->disp_source);
sdRef->disp_source = NULL;
}
// if disp_queue is set, it means it used the DNSServiceSetDispatchQueue API. In that case,
// when the source was cancelled, the fd was closed in the handler. Currently the source
// is cancelled only when the mDNSResponder daemon dies
else if (!sdRef->disp_queue) dnssd_close(sdRef->sockfd);
#else
dnssd_close(sdRef->sockfd);
#endif
// Free DNSRecords added in DNSRegisterRecord if they have not
// been freed in DNSRemoveRecord
while (sdRef)
{
DNSServiceOp *p = sdRef;
sdRef = sdRef->next;
// When there is an error reading from the daemon e.g., bad fd, CallbackWithError
// is called which sets moreptr. It might set the moreptr on a subordinate sdRef
// but the application might call DNSServiceRefDeallocate with the main sdRef from
// the callback. Hence, when we loop through the subordinate sdRefs, we need
// to clear the moreptr so that CallbackWithError can terminate itself instead of
// walking through the freed sdRefs.
if (p->moreptr) *(p->moreptr) = 0;
FreeDNSServiceOp(p);
}
}
}
DNSServiceErrorType DNSSD_API DNSServiceGetProperty(const char *property, void *result, uint32_t *size)
{
DNSServiceErrorType err;
char *ptr;
size_t len;
ipc_msg_hdr *hdr;
DNSServiceOp *tmp;
uint32_t actualsize;
if (!property || !result || !size)
return kDNSServiceErr_BadParam;
len = strlen(property) + 1;
err = ConnectToServer(&tmp, 0, getproperty_request, NULL, NULL, NULL);
if (err) return err;
hdr = create_hdr(getproperty_request, &len, &ptr, 0, tmp);
if (!hdr) { DNSServiceRefDeallocate(tmp); return kDNSServiceErr_NoMemory; }
put_string(property, &ptr);
err = deliver_request(hdr, tmp); // Will free hdr for us
if (err) { DNSServiceRefDeallocate(tmp); return err; }
if (read_all(tmp->sockfd, (char*)&actualsize, (int)sizeof(actualsize)) < 0)
{ DNSServiceRefDeallocate(tmp); return kDNSServiceErr_ServiceNotRunning; }
actualsize = ntohl(actualsize);
if (read_all(tmp->sockfd, (char*)result, actualsize < *size ? actualsize : *size) < 0)
{ DNSServiceRefDeallocate(tmp); return kDNSServiceErr_ServiceNotRunning; }
DNSServiceRefDeallocate(tmp);
// Swap version result back to local process byte order
if (!strcmp(property, kDNSServiceProperty_DaemonVersion) && *size >= 4)
*(uint32_t*)result = ntohl(*(uint32_t*)result);
*size = actualsize;
return kDNSServiceErr_NoError;
}
DNSServiceErrorType DNSSD_API DNSServiceGetPID(const uint16_t srcport, int32_t *pid)
{
char *ptr;
ipc_msg_hdr *hdr;
DNSServiceOp *tmp = NULL;
size_t len = sizeof(int32_t);
DNSServiceErrorType err = ConnectToServer(&tmp, 0, getpid_request, NULL, NULL, NULL);
if (err) return err;
hdr = create_hdr(getpid_request, &len, &ptr, 0, tmp);
if (!hdr) { DNSServiceRefDeallocate(tmp); return kDNSServiceErr_NoMemory; }
put_uint16(srcport, &ptr);
err = deliver_request(hdr, tmp); // Will free hdr for us
if (err) { DNSServiceRefDeallocate(tmp); return err; }
if (read_all(tmp->sockfd, (char*)pid, sizeof(int32_t)) < 0)
{ DNSServiceRefDeallocate(tmp); return kDNSServiceErr_ServiceNotRunning; }
DNSServiceRefDeallocate(tmp);
return kDNSServiceErr_NoError;
}
static void handle_resolve_response(DNSServiceOp *const sdr, const CallbackHeader *const cbh, const char *data, const char *end)
{
char fullname[kDNSServiceMaxDomainName];
char target[kDNSServiceMaxDomainName];
uint16_t txtlen;
union { uint16_t s; u_char b[2]; } port;
unsigned char *txtrecord;
get_string(&data, end, fullname, kDNSServiceMaxDomainName);
get_string(&data, end, target, kDNSServiceMaxDomainName);
if (!data || data + 2 > end) goto fail;
port.b[0] = *data++;
port.b[1] = *data++;
txtlen = get_uint16(&data, end);
txtrecord = (unsigned char *)get_rdata(&data, end, txtlen);
if (!data) goto fail;
((DNSServiceResolveReply)sdr->AppCallback)(sdr, cbh->cb_flags, cbh->cb_interface, cbh->cb_err, fullname, target, port.s, txtlen, txtrecord, sdr->AppContext);
return;
// MUST NOT touch sdr after invoking AppCallback -- client is allowed to dispose it from within callback function
fail:
syslog(LOG_WARNING, "dnssd_clientstub handle_resolve_response: error reading result from daemon");
}
#if TARGET_OS_EMBEDDED
static int32_t libSystemVersion = 0;
// Return true if the iOS application linked against a version of libsystem where P2P
// interfaces were included by default when using kDNSServiceInterfaceIndexAny.
// Using 160.0.0 == 0xa00000 as the version threshold.
static int includeP2PWithIndexAny()
{
if (libSystemVersion == 0)
libSystemVersion = NSVersionOfLinkTimeLibrary("System");
if (libSystemVersion < 0xa00000)
return 1;
else
return 0;
}
#else // TARGET_OS_EMBEDDED
// always return false for non iOS platforms
static int includeP2PWithIndexAny()
{
return 0;
}
#endif // TARGET_OS_EMBEDDED
DNSServiceErrorType DNSSD_API DNSServiceResolve
(
DNSServiceRef *sdRef,
DNSServiceFlags flags,
uint32_t interfaceIndex,
const char *name,
const char *regtype,
const char *domain,
DNSServiceResolveReply callBack,
void *context
)
{
char *ptr;
size_t len;
ipc_msg_hdr *hdr;
DNSServiceErrorType err;
if (!sdRef || !name || !regtype || !domain || !callBack) return kDNSServiceErr_BadParam;
// Need a real InterfaceID for WakeOnResolve
if ((flags & kDNSServiceFlagsWakeOnResolve) != 0 &&
((interfaceIndex == kDNSServiceInterfaceIndexAny) ||
(interfaceIndex == kDNSServiceInterfaceIndexLocalOnly) ||
(interfaceIndex == kDNSServiceInterfaceIndexUnicast) ||
(interfaceIndex == kDNSServiceInterfaceIndexP2P) ||
(interfaceIndex == kDNSServiceInterfaceIndexBLE)))
{
return kDNSServiceErr_BadParam;
}
if ((interfaceIndex == kDNSServiceInterfaceIndexAny) && includeP2PWithIndexAny())
flags |= kDNSServiceFlagsIncludeP2P;
err = ConnectToServer(sdRef, flags, resolve_request, handle_resolve_response, callBack, context);
if (err) return err; // On error ConnectToServer leaves *sdRef set to NULL
// Calculate total message length
len = sizeof(flags);
len += sizeof(interfaceIndex);
len += strlen(name) + 1;
len += strlen(regtype) + 1;
len += strlen(domain) + 1;
hdr = create_hdr(resolve_request, &len, &ptr, (*sdRef)->primary ? 1 : 0, *sdRef);
if (!hdr) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; return kDNSServiceErr_NoMemory; }
put_flags(flags, &ptr);
put_uint32(interfaceIndex, &ptr);
put_string(name, &ptr);
put_string(regtype, &ptr);
put_string(domain, &ptr);
err = deliver_request(hdr, *sdRef); // Will free hdr for us
if (err) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; }
return err;
}
static void handle_query_response(DNSServiceOp *const sdr, const CallbackHeader *const cbh, const char *data, const char *const end)
{
uint32_t ttl;
char name[kDNSServiceMaxDomainName];
uint16_t rrtype, rrclass, rdlen;
const char *rdata;
get_string(&data, end, name, kDNSServiceMaxDomainName);
rrtype = get_uint16(&data, end);
rrclass = get_uint16(&data, end);
rdlen = get_uint16(&data, end);
rdata = get_rdata(&data, end, rdlen);
ttl = get_uint32(&data, end);
if (!data) syslog(LOG_WARNING, "dnssd_clientstub handle_query_response: error reading result from daemon");
else ((DNSServiceQueryRecordReply)sdr->AppCallback)(sdr, cbh->cb_flags, cbh->cb_interface, cbh->cb_err, name, rrtype, rrclass, rdlen, rdata, ttl, sdr->AppContext);
// MUST NOT touch sdr after invoking AppCallback -- client is allowed to dispose it from within callback function
}
DNSServiceErrorType DNSSD_API DNSServiceQueryRecord
(
DNSServiceRef *sdRef,
DNSServiceFlags flags,
uint32_t interfaceIndex,
const char *name,
uint16_t rrtype,
uint16_t rrclass,
DNSServiceQueryRecordReply callBack,
void *context
)
{
char *ptr;
size_t len;
ipc_msg_hdr *hdr;
DNSServiceErrorType err;
// NULL name handled below.
if (!sdRef || !callBack) return kDNSServiceErr_BadParam;
if ((interfaceIndex == kDNSServiceInterfaceIndexAny) && includeP2PWithIndexAny())
flags |= kDNSServiceFlagsIncludeP2P;
err = ConnectToServer(sdRef, flags, query_request, handle_query_response, callBack, context);
if (err) return err; // On error ConnectToServer leaves *sdRef set to NULL
if (!name) name = "\0";
// Calculate total message length
len = sizeof(flags);
len += sizeof(uint32_t); // interfaceIndex
len += strlen(name) + 1;
len += 2 * sizeof(uint16_t); // rrtype, rrclass
hdr = create_hdr(query_request, &len, &ptr, (*sdRef)->primary ? 1 : 0, *sdRef);
if (!hdr) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; return kDNSServiceErr_NoMemory; }
put_flags(flags, &ptr);
put_uint32(interfaceIndex, &ptr);
put_string(name, &ptr);
put_uint16(rrtype, &ptr);
put_uint16(rrclass, &ptr);
err = deliver_request(hdr, *sdRef); // Will free hdr for us
if (err) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; }
return err;
}
static void handle_addrinfo_response(DNSServiceOp *const sdr, const CallbackHeader *const cbh, const char *data, const char *const end)
{
char hostname[kDNSServiceMaxDomainName];
uint16_t rrtype, rrclass, rdlen;
const char *rdata;
uint32_t ttl;
get_string(&data, end, hostname, kDNSServiceMaxDomainName);
rrtype = get_uint16(&data, end);
rrclass = get_uint16(&data, end);
rdlen = get_uint16(&data, end);
rdata = get_rdata (&data, end, rdlen);
ttl = get_uint32(&data, end);
(void)rrclass; // Unused
// We only generate client callbacks for A and AAAA results (including NXDOMAIN results for
// those types, if the client has requested those with the kDNSServiceFlagsReturnIntermediates).
// Other result types, specifically CNAME referrals, are not communicated to the client, because
// the DNSServiceGetAddrInfoReply interface doesn't have any meaningful way to communiate CNAME referrals.
if (!data) syslog(LOG_WARNING, "dnssd_clientstub handle_addrinfo_response: error reading result from daemon");
else if (rrtype == kDNSServiceType_A || rrtype == kDNSServiceType_AAAA)
{
struct sockaddr_in sa4;
struct sockaddr_in6 sa6;
const struct sockaddr *const sa = (rrtype == kDNSServiceType_A) ? (struct sockaddr*)&sa4 : (struct sockaddr*)&sa6;
if (rrtype == kDNSServiceType_A)
{
memset(&sa4, 0, sizeof(sa4));
#ifndef NOT_HAVE_SA_LEN
sa4.sin_len = sizeof(struct sockaddr_in);
#endif
sa4.sin_family = AF_INET;
// sin_port = 0;
if (!cbh->cb_err) memcpy(&sa4.sin_addr, rdata, rdlen);
}
else
{
memset(&sa6, 0, sizeof(sa6));
#ifndef NOT_HAVE_SA_LEN
sa6.sin6_len = sizeof(struct sockaddr_in6);
#endif
sa6.sin6_family = AF_INET6;
// sin6_port = 0;
// sin6_flowinfo = 0;
// sin6_scope_id = 0;
if (!cbh->cb_err)
{
memcpy(&sa6.sin6_addr, rdata, rdlen);
if (IN6_IS_ADDR_LINKLOCAL(&sa6.sin6_addr)) sa6.sin6_scope_id = cbh->cb_interface;
}
}
// Validation results are always delivered separately from the actual results of the
// DNSServiceGetAddrInfo. Set the "addr" to NULL as per the documentation.
//
// Note: If we deliver validation results along with the "addr" in the future, we need
// a way to differentiate the negative response from validation-only response as both
// has zero address.
if (!(cbh->cb_flags & kDNSServiceFlagsValidate))
((DNSServiceGetAddrInfoReply)sdr->AppCallback)(sdr, cbh->cb_flags, cbh->cb_interface, cbh->cb_err, hostname, sa, ttl, sdr->AppContext);
else
((DNSServiceGetAddrInfoReply)sdr->AppCallback)(sdr, cbh->cb_flags, cbh->cb_interface, cbh->cb_err, hostname, NULL, 0, sdr->AppContext);
// MUST NOT touch sdr after invoking AppCallback -- client is allowed to dispose it from within callback function
}
}
DNSServiceErrorType DNSSD_API DNSServiceGetAddrInfo
(
DNSServiceRef *sdRef,
DNSServiceFlags flags,
uint32_t interfaceIndex,
uint32_t protocol,
const char *hostname,
DNSServiceGetAddrInfoReply callBack,
void *context /* may be NULL */
)
{
char *ptr;
size_t len;
ipc_msg_hdr *hdr;
DNSServiceErrorType err;
if (!sdRef || !hostname || !callBack) return kDNSServiceErr_BadParam;
err = ConnectToServer(sdRef, flags, addrinfo_request, handle_addrinfo_response, callBack, context);
if (err)
{
return err; // On error ConnectToServer leaves *sdRef set to NULL
}
// Calculate total message length
len = sizeof(flags);
len += sizeof(uint32_t); // interfaceIndex
len += sizeof(uint32_t); // protocol
len += strlen(hostname) + 1;
hdr = create_hdr(addrinfo_request, &len, &ptr, (*sdRef)->primary ? 1 : 0, *sdRef);
if (!hdr) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; return kDNSServiceErr_NoMemory; }
put_flags(flags, &ptr);
put_uint32(interfaceIndex, &ptr);
put_uint32(protocol, &ptr);
put_string(hostname, &ptr);
err = deliver_request(hdr, *sdRef); // Will free hdr for us
if (err) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; }
return err;
}
static void handle_browse_response(DNSServiceOp *const sdr, const CallbackHeader *const cbh, const char *data, const char *const end)
{
char replyName[256], replyType[kDNSServiceMaxDomainName], replyDomain[kDNSServiceMaxDomainName];
get_string(&data, end, replyName, 256);
get_string(&data, end, replyType, kDNSServiceMaxDomainName);
get_string(&data, end, replyDomain, kDNSServiceMaxDomainName);
if (!data) syslog(LOG_WARNING, "dnssd_clientstub handle_browse_response: error reading result from daemon");
else ((DNSServiceBrowseReply)sdr->AppCallback)(sdr, cbh->cb_flags, cbh->cb_interface, cbh->cb_err, replyName, replyType, replyDomain, sdr->AppContext);
// MUST NOT touch sdr after invoking AppCallback -- client is allowed to dispose it from within callback function
}
DNSServiceErrorType DNSSD_API DNSServiceBrowse
(
DNSServiceRef *sdRef,
DNSServiceFlags flags,
uint32_t interfaceIndex,
const char *regtype,
const char *domain,
DNSServiceBrowseReply callBack,
void *context
)
{
char *ptr;
size_t len;
ipc_msg_hdr *hdr;
DNSServiceErrorType err;
// NULL domain handled below
if (!sdRef || !regtype || !callBack) return kDNSServiceErr_BadParam;
if ((interfaceIndex == kDNSServiceInterfaceIndexAny) && includeP2PWithIndexAny())
flags |= kDNSServiceFlagsIncludeP2P;
err = ConnectToServer(sdRef, flags, browse_request, handle_browse_response, callBack, context);
if (err) return err; // On error ConnectToServer leaves *sdRef set to NULL
if (!domain) domain = "";
len = sizeof(flags);
len += sizeof(interfaceIndex);
len += strlen(regtype) + 1;
len += strlen(domain) + 1;
hdr = create_hdr(browse_request, &len, &ptr, (*sdRef)->primary ? 1 : 0, *sdRef);
if (!hdr) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; return kDNSServiceErr_NoMemory; }
put_flags(flags, &ptr);
put_uint32(interfaceIndex, &ptr);
put_string(regtype, &ptr);
put_string(domain, &ptr);
err = deliver_request(hdr, *sdRef); // Will free hdr for us
if (err) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; }
return err;
}
DNSServiceErrorType DNSSD_API DNSServiceSetDefaultDomainForUser(DNSServiceFlags flags, const char *domain);
DNSServiceErrorType DNSSD_API DNSServiceSetDefaultDomainForUser(DNSServiceFlags flags, const char *domain)
{
DNSServiceErrorType err;
DNSServiceOp *tmp;
char *ptr;
size_t len;
ipc_msg_hdr *hdr;
if (!domain) return kDNSServiceErr_BadParam;
len = sizeof(flags) + strlen(domain) + 1;
err = ConnectToServer(&tmp, 0, setdomain_request, NULL, NULL, NULL);
if (err) return err;
hdr = create_hdr(setdomain_request, &len, &ptr, 0, tmp);
if (!hdr) { DNSServiceRefDeallocate(tmp); return kDNSServiceErr_NoMemory; }
put_flags(flags, &ptr);
put_string(domain, &ptr);
err = deliver_request(hdr, tmp); // Will free hdr for us
DNSServiceRefDeallocate(tmp);
return err;
}
static void handle_regservice_response(DNSServiceOp *const sdr, const CallbackHeader *const cbh, const char *data, const char *const end)
{
char name[256], regtype[kDNSServiceMaxDomainName], domain[kDNSServiceMaxDomainName];
get_string(&data, end, name, 256);
get_string(&data, end, regtype, kDNSServiceMaxDomainName);
get_string(&data, end, domain, kDNSServiceMaxDomainName);
if (!data) syslog(LOG_WARNING, "dnssd_clientstub handle_regservice_response: error reading result from daemon");
else ((DNSServiceRegisterReply)sdr->AppCallback)(sdr, cbh->cb_flags, cbh->cb_err, name, regtype, domain, sdr->AppContext);
// MUST NOT touch sdr after invoking AppCallback -- client is allowed to dispose it from within callback function
}
DNSServiceErrorType DNSSD_API DNSServiceRegister
(
DNSServiceRef *sdRef,
DNSServiceFlags flags,
uint32_t interfaceIndex,
const char *name,
const char *regtype,
const char *domain,
const char *host,
uint16_t PortInNetworkByteOrder,
uint16_t txtLen,
const void *txtRecord,
DNSServiceRegisterReply callBack,
void *context
)
{
char *ptr;
size_t len;
ipc_msg_hdr *hdr;
DNSServiceErrorType err;
union { uint16_t s; u_char b[2]; } port = { PortInNetworkByteOrder };
if (!sdRef || !regtype) return kDNSServiceErr_BadParam;
if (!name) name = "";
if (!domain) domain = "";
if (!host) host = "";
if (!txtRecord) txtRecord = (void*)"";
// No callback must have auto-rename
if (!callBack && (flags & kDNSServiceFlagsNoAutoRename)) return kDNSServiceErr_BadParam;
if ((interfaceIndex == kDNSServiceInterfaceIndexAny) && includeP2PWithIndexAny())
flags |= kDNSServiceFlagsIncludeP2P;
err = ConnectToServer(sdRef, flags, reg_service_request, callBack ? handle_regservice_response : NULL, callBack, context);
if (err) return err; // On error ConnectToServer leaves *sdRef set to NULL
len = sizeof(DNSServiceFlags);
len += sizeof(uint32_t); // interfaceIndex
len += strlen(name) + strlen(regtype) + strlen(domain) + strlen(host) + 4;
len += 2 * sizeof(uint16_t); // port, txtLen
len += txtLen;
hdr = create_hdr(reg_service_request, &len, &ptr, (*sdRef)->primary ? 1 : 0, *sdRef);
if (!hdr) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; return kDNSServiceErr_NoMemory; }
if (!callBack) hdr->ipc_flags |= IPC_FLAGS_NOREPLY;
put_flags(flags, &ptr);
put_uint32(interfaceIndex, &ptr);
put_string(name, &ptr);
put_string(regtype, &ptr);
put_string(domain, &ptr);
put_string(host, &ptr);
*ptr++ = port.b[0];
*ptr++ = port.b[1];
put_uint16(txtLen, &ptr);
put_rdata(txtLen, txtRecord, &ptr);
err = deliver_request(hdr, *sdRef); // Will free hdr for us
if (err) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; }
return err;
}
static void handle_enumeration_response(DNSServiceOp *const sdr, const CallbackHeader *const cbh, const char *data, const char *const end)
{
char domain[kDNSServiceMaxDomainName];
get_string(&data, end, domain, kDNSServiceMaxDomainName);
if (!data) syslog(LOG_WARNING, "dnssd_clientstub handle_enumeration_response: error reading result from daemon");
else ((DNSServiceDomainEnumReply)sdr->AppCallback)(sdr, cbh->cb_flags, cbh->cb_interface, cbh->cb_err, domain, sdr->AppContext);
// MUST NOT touch sdr after invoking AppCallback -- client is allowed to dispose it from within callback function
}
DNSServiceErrorType DNSSD_API DNSServiceEnumerateDomains
(
DNSServiceRef *sdRef,
DNSServiceFlags flags,
uint32_t interfaceIndex,
DNSServiceDomainEnumReply callBack,
void *context
)
{
char *ptr;
size_t len;
ipc_msg_hdr *hdr;
DNSServiceErrorType err;
int f1;
int f2;
if (!sdRef || !callBack) return kDNSServiceErr_BadParam;
f1 = (flags & kDNSServiceFlagsBrowseDomains) != 0;
f2 = (flags & kDNSServiceFlagsRegistrationDomains) != 0;
if (f1 + f2 != 1) return kDNSServiceErr_BadParam;
err = ConnectToServer(sdRef, flags, enumeration_request, handle_enumeration_response, callBack, context);
if (err) return err; // On error ConnectToServer leaves *sdRef set to NULL
len = sizeof(DNSServiceFlags);
len += sizeof(uint32_t);
hdr = create_hdr(enumeration_request, &len, &ptr, (*sdRef)->primary ? 1 : 0, *sdRef);
if (!hdr) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; return kDNSServiceErr_NoMemory; }
put_flags(flags, &ptr);
put_uint32(interfaceIndex, &ptr);
err = deliver_request(hdr, *sdRef); // Will free hdr for us
if (err) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; }
return err;
}
static void ConnectionResponse(DNSServiceOp *const sdr, const CallbackHeader *const cbh, const char *const data, const char *const end)
{
(void)data; // Unused
//printf("ConnectionResponse got %d\n", cbh->ipc_hdr.op);
if (cbh->ipc_hdr.op != reg_record_reply_op)
{
// When using kDNSServiceFlagsShareConnection, need to search the list of associated DNSServiceOps
// to find the one this response is intended for, and then call through to its ProcessReply handler.
// We start with our first subordinate DNSServiceRef -- don't want to accidentally match the parent DNSServiceRef.
DNSServiceOp *op = sdr->next;
while (op && (op->uid.u32[0] != cbh->ipc_hdr.client_context.u32[0] || op->uid.u32[1] != cbh->ipc_hdr.client_context.u32[1]))
op = op->next;
// Note: We may sometimes not find a matching DNSServiceOp, in the case where the client has
// cancelled the subordinate DNSServiceOp, but there are still messages in the pipeline from the daemon
if (op && op->ProcessReply) op->ProcessReply(op, cbh, data, end);
// WARNING: Don't touch op or sdr after this -- client may have called DNSServiceRefDeallocate
return;
}
else
{
DNSRecordRef rec;
for (rec = sdr->rec; rec; rec = rec->recnext)
{
if (rec->uid.u32[0] == cbh->ipc_hdr.client_context.u32[0] && rec->uid.u32[1] == cbh->ipc_hdr.client_context.u32[1])
break;
}
// The record might have been freed already and hence not an
// error if the record is not found.
if (!rec)
{
syslog(LOG_INFO, "ConnectionResponse: Record not found");
return;
}
if (rec->sdr != sdr)
{
syslog(LOG_WARNING, "ConnectionResponse: Record sdr mismatch: rec %p sdr %p", rec->sdr, sdr);
return;
}
if (sdr->op == connection_request || sdr->op == connection_delegate_request)
{
rec->AppCallback(rec->sdr, rec, cbh->cb_flags, cbh->cb_err, rec->AppContext);
}
else
{
syslog(LOG_WARNING, "dnssd_clientstub ConnectionResponse: sdr->op != connection_request");
rec->AppCallback(rec->sdr, rec, 0, kDNSServiceErr_Unknown, rec->AppContext);
}
// MUST NOT touch sdr after invoking AppCallback -- client is allowed to dispose it from within callback function
}
}
DNSServiceErrorType DNSSD_API DNSServiceCreateConnection(DNSServiceRef *sdRef)
{
DNSServiceErrorType err;
char *ptr;
size_t len = 0;
ipc_msg_hdr *hdr;
if (!sdRef) return kDNSServiceErr_BadParam;
err = ConnectToServer(sdRef, 0, connection_request, ConnectionResponse, NULL, NULL);
if (err) return err; // On error ConnectToServer leaves *sdRef set to NULL
hdr = create_hdr(connection_request, &len, &ptr, 0, *sdRef);
if (!hdr) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; return kDNSServiceErr_NoMemory; }
err = deliver_request(hdr, *sdRef); // Will free hdr for us
if (err) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; }
return err;
}
#if APPLE_OSX_mDNSResponder && !TARGET_IPHONE_SIMULATOR
DNSServiceErrorType DNSSD_API DNSServiceCreateDelegateConnection(DNSServiceRef *sdRef, int32_t pid, uuid_t uuid)
{
char *ptr;
size_t len = 0;
ipc_msg_hdr *hdr;
if (!sdRef) return kDNSServiceErr_BadParam;
DNSServiceErrorType err = ConnectToServer(sdRef, 0, connection_delegate_request, ConnectionResponse, NULL, NULL);
if (err)
{
return err; // On error ConnectToServer leaves *sdRef set to NULL
}
// Only one of the two options can be set. If pid is zero, uuid is used.
// If both are specified only pid will be used. We send across the pid
// so that the daemon knows what to read from the socket.
len += sizeof(int32_t);
hdr = create_hdr(connection_delegate_request, &len, &ptr, 0, *sdRef);
if (!hdr)
{
DNSServiceRefDeallocate(*sdRef);
*sdRef = NULL;
return kDNSServiceErr_NoMemory;
}
if (pid && setsockopt((*sdRef)->sockfd, SOL_SOCKET, SO_DELEGATED, &pid, sizeof(pid)) == -1)
{
syslog(LOG_WARNING, "dnssdclientstub: Could not setsockopt() for PID[%d], no entitlements or process(pid) invalid errno:%d (%s)", pid, errno, strerror(errno));
// Free the hdr in case we return before calling deliver_request()
if (hdr)
free(hdr);
DNSServiceRefDeallocate(*sdRef);
*sdRef = NULL;
return kDNSServiceErr_NoAuth;
}
if (!pid && setsockopt((*sdRef)->sockfd, SOL_SOCKET, SO_DELEGATED_UUID, uuid, sizeof(uuid_t)) == -1)
{
syslog(LOG_WARNING, "dnssdclientstub: Could not setsockopt() for UUID, no entitlements or process(uuid) invalid errno:%d (%s) ", errno, strerror(errno));
// Free the hdr in case we return before calling deliver_request()
if (hdr)
free(hdr);
DNSServiceRefDeallocate(*sdRef);
*sdRef = NULL;
return kDNSServiceErr_NoAuth;
}
put_uint32(pid, &ptr);
err = deliver_request(hdr, *sdRef); // Will free hdr for us
if (err)
{
DNSServiceRefDeallocate(*sdRef);
*sdRef = NULL;
}
return err;
}
#elif TARGET_IPHONE_SIMULATOR // This hack is for Simulator platform only
DNSServiceErrorType DNSSD_API DNSServiceCreateDelegateConnection(DNSServiceRef *sdRef, int32_t pid, uuid_t uuid)
{
(void) pid;
(void) uuid;
return DNSServiceCreateConnection(sdRef);
}
#endif
DNSServiceErrorType DNSSD_API DNSServiceRegisterRecord
(
DNSServiceRef sdRef,
DNSRecordRef *RecordRef,
DNSServiceFlags flags,
uint32_t interfaceIndex,
const char *fullname,
uint16_t rrtype,
uint16_t rrclass,
uint16_t rdlen,
const void *rdata,
uint32_t ttl,
DNSServiceRegisterRecordReply callBack,
void *context
)
{
char *ptr;
size_t len;
ipc_msg_hdr *hdr = NULL;
DNSRecordRef rref = NULL;
DNSRecord **p;
int f1 = (flags & kDNSServiceFlagsShared) != 0;
int f2 = (flags & kDNSServiceFlagsUnique) != 0;
if (f1 + f2 != 1) return kDNSServiceErr_BadParam;
if ((interfaceIndex == kDNSServiceInterfaceIndexAny) && includeP2PWithIndexAny())
flags |= kDNSServiceFlagsIncludeP2P;
if (!sdRef || !RecordRef || !fullname || (!rdata && rdlen) || !callBack)
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceRegisterRecord called with NULL parameter");
return kDNSServiceErr_BadParam;
}
if (!DNSServiceRefValid(sdRef))
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceRegisterRecord called with invalid DNSServiceRef %p %08X %08X", sdRef, sdRef->sockfd, sdRef->validator);
return kDNSServiceErr_BadReference;
}
if (sdRef->op != connection_request && sdRef->op != connection_delegate_request)
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceRegisterRecord called with non-DNSServiceCreateConnection DNSServiceRef %p %d", sdRef, sdRef->op);
return kDNSServiceErr_BadReference;
}
*RecordRef = NULL;
len = sizeof(DNSServiceFlags);
len += 2 * sizeof(uint32_t); // interfaceIndex, ttl
len += 3 * sizeof(uint16_t); // rrtype, rrclass, rdlen
len += strlen(fullname) + 1;
len += rdlen;
// Bump up the uid. Normally for shared operations (kDNSServiceFlagsShareConnection), this
// is done in ConnectToServer. For DNSServiceRegisterRecord, ConnectToServer has already
// been called. As multiple DNSServiceRegisterRecords can be multiplexed over a single
// connection, we need a way to demultiplex the response so that the callback corresponding
// to the right DNSServiceRegisterRecord instance can be called. Use the same mechanism that
// is used by kDNSServiceFlagsShareConnection. create_hdr copies the uid value to ipc
// hdr->client_context which will be returned in the ipc response.
if (++sdRef->uid.u32[0] == 0)
++sdRef->uid.u32[1];
hdr = create_hdr(reg_record_request, &len, &ptr, 1, sdRef);
if (!hdr) return kDNSServiceErr_NoMemory;
put_flags(flags, &ptr);
put_uint32(interfaceIndex, &ptr);
put_string(fullname, &ptr);
put_uint16(rrtype, &ptr);
put_uint16(rrclass, &ptr);
put_uint16(rdlen, &ptr);
put_rdata(rdlen, rdata, &ptr);
put_uint32(ttl, &ptr);
rref = malloc(sizeof(DNSRecord));
if (!rref) { free(hdr); return kDNSServiceErr_NoMemory; }
rref->AppContext = context;
rref->AppCallback = callBack;
rref->record_index = sdRef->max_index++;
rref->sdr = sdRef;
rref->recnext = NULL;
*RecordRef = rref;
// Remember the uid that we are sending across so that we can match
// when the response comes back.
rref->uid = sdRef->uid;
hdr->reg_index = rref->record_index;
p = &(sdRef)->rec;
while (*p) p = &(*p)->recnext;
*p = rref;
return deliver_request(hdr, sdRef); // Will free hdr for us
}
// sdRef returned by DNSServiceRegister()
DNSServiceErrorType DNSSD_API DNSServiceAddRecord
(
DNSServiceRef sdRef,
DNSRecordRef *RecordRef,
DNSServiceFlags flags,
uint16_t rrtype,
uint16_t rdlen,
const void *rdata,
uint32_t ttl
)
{
ipc_msg_hdr *hdr;
size_t len = 0;
char *ptr;
DNSRecordRef rref;
DNSRecord **p;
if (!sdRef || !RecordRef || (!rdata && rdlen))
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceAddRecord called with NULL parameter");
return kDNSServiceErr_BadParam;
}
if (sdRef->op != reg_service_request)
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceAddRecord called with non-DNSServiceRegister DNSServiceRef %p %d", sdRef, sdRef->op);
return kDNSServiceErr_BadReference;
}
if (!DNSServiceRefValid(sdRef))
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceAddRecord called with invalid DNSServiceRef %p %08X %08X", sdRef, sdRef->sockfd, sdRef->validator);
return kDNSServiceErr_BadReference;
}
*RecordRef = NULL;
len += 2 * sizeof(uint16_t); // rrtype, rdlen
len += rdlen;
len += sizeof(uint32_t);
len += sizeof(DNSServiceFlags);
hdr = create_hdr(add_record_request, &len, &ptr, 1, sdRef);
if (!hdr) return kDNSServiceErr_NoMemory;
put_flags(flags, &ptr);
put_uint16(rrtype, &ptr);
put_uint16(rdlen, &ptr);
put_rdata(rdlen, rdata, &ptr);
put_uint32(ttl, &ptr);
rref = malloc(sizeof(DNSRecord));
if (!rref) { free(hdr); return kDNSServiceErr_NoMemory; }
rref->AppContext = NULL;
rref->AppCallback = NULL;
rref->record_index = sdRef->max_index++;
rref->sdr = sdRef;
rref->recnext = NULL;
*RecordRef = rref;
hdr->reg_index = rref->record_index;
p = &(sdRef)->rec;
while (*p) p = &(*p)->recnext;
*p = rref;
return deliver_request(hdr, sdRef); // Will free hdr for us
}
// DNSRecordRef returned by DNSServiceRegisterRecord or DNSServiceAddRecord
DNSServiceErrorType DNSSD_API DNSServiceUpdateRecord
(
DNSServiceRef sdRef,
DNSRecordRef RecordRef,
DNSServiceFlags flags,
uint16_t rdlen,
const void *rdata,
uint32_t ttl
)
{
ipc_msg_hdr *hdr;
size_t len = 0;
char *ptr;
if (!sdRef || (!rdata && rdlen))
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceUpdateRecord called with NULL parameter");
return kDNSServiceErr_BadParam;
}
if (!DNSServiceRefValid(sdRef))
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceUpdateRecord called with invalid DNSServiceRef %p %08X %08X", sdRef, sdRef->sockfd, sdRef->validator);
return kDNSServiceErr_BadReference;
}
// Note: RecordRef is allowed to be NULL
len += sizeof(uint16_t);
len += rdlen;
len += sizeof(uint32_t);
len += sizeof(DNSServiceFlags);
hdr = create_hdr(update_record_request, &len, &ptr, 1, sdRef);
if (!hdr) return kDNSServiceErr_NoMemory;
hdr->reg_index = RecordRef ? RecordRef->record_index : TXT_RECORD_INDEX;
put_flags(flags, &ptr);
put_uint16(rdlen, &ptr);
put_rdata(rdlen, rdata, &ptr);
put_uint32(ttl, &ptr);
return deliver_request(hdr, sdRef); // Will free hdr for us
}
DNSServiceErrorType DNSSD_API DNSServiceRemoveRecord
(
DNSServiceRef sdRef,
DNSRecordRef RecordRef,
DNSServiceFlags flags
)
{
ipc_msg_hdr *hdr;
size_t len = 0;
char *ptr;
DNSServiceErrorType err;
if (!sdRef) { syslog(LOG_WARNING, "dnssd_clientstub DNSServiceRemoveRecord called with NULL DNSServiceRef"); return kDNSServiceErr_BadParam; }
if (!RecordRef) { syslog(LOG_WARNING, "dnssd_clientstub DNSServiceRemoveRecord called with NULL DNSRecordRef"); return kDNSServiceErr_BadParam; }
if (!sdRef->max_index) { syslog(LOG_WARNING, "dnssd_clientstub DNSServiceRemoveRecord called with bad DNSServiceRef"); return kDNSServiceErr_BadReference; }
if (!DNSServiceRefValid(sdRef))
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceRemoveRecord called with invalid DNSServiceRef %p %08X %08X", sdRef, sdRef->sockfd, sdRef->validator);
return kDNSServiceErr_BadReference;
}
len += sizeof(flags);
hdr = create_hdr(remove_record_request, &len, &ptr, 1, sdRef);
if (!hdr) return kDNSServiceErr_NoMemory;
hdr->reg_index = RecordRef->record_index;
put_flags(flags, &ptr);
err = deliver_request(hdr, sdRef); // Will free hdr for us
if (!err)
{
// This RecordRef could have been allocated in DNSServiceRegisterRecord or DNSServiceAddRecord.
// If so, delink from the list before freeing
DNSRecord **p = &sdRef->rec;
while (*p && *p != RecordRef) p = &(*p)->recnext;
if (*p) *p = RecordRef->recnext;
free(RecordRef);
}
return err;
}
DNSServiceErrorType DNSSD_API DNSServiceReconfirmRecord
(
DNSServiceFlags flags,
uint32_t interfaceIndex,
const char *fullname,
uint16_t rrtype,
uint16_t rrclass,
uint16_t rdlen,
const void *rdata
)
{
DNSServiceErrorType err;
char *ptr;
size_t len;
ipc_msg_hdr *hdr;
DNSServiceOp *tmp = NULL;
if (!fullname || (!rdata && rdlen)) return kDNSServiceErr_BadParam;
err = ConnectToServer(&tmp, flags, reconfirm_record_request, NULL, NULL, NULL);
if (err) return err;
len = sizeof(DNSServiceFlags);
len += sizeof(uint32_t);
len += strlen(fullname) + 1;
len += 3 * sizeof(uint16_t);
len += rdlen;
hdr = create_hdr(reconfirm_record_request, &len, &ptr, 0, tmp);
if (!hdr) { DNSServiceRefDeallocate(tmp); return kDNSServiceErr_NoMemory; }
put_flags(flags, &ptr);
put_uint32(interfaceIndex, &ptr);
put_string(fullname, &ptr);
put_uint16(rrtype, &ptr);
put_uint16(rrclass, &ptr);
put_uint16(rdlen, &ptr);
put_rdata(rdlen, rdata, &ptr);
err = deliver_request(hdr, tmp); // Will free hdr for us
DNSServiceRefDeallocate(tmp);
return err;
}
static void handle_port_mapping_response(DNSServiceOp *const sdr, const CallbackHeader *const cbh, const char *data, const char *const end)
{
union { uint32_t l; u_char b[4]; } addr;
uint8_t protocol;
union { uint16_t s; u_char b[2]; } internalPort;
union { uint16_t s; u_char b[2]; } externalPort;
uint32_t ttl;
if (!data || data + 13 > end) goto fail;
addr.b[0] = *data++;
addr.b[1] = *data++;
addr.b[2] = *data++;
addr.b[3] = *data++;
protocol = *data++;
internalPort.b[0] = *data++;
internalPort.b[1] = *data++;
externalPort.b[0] = *data++;
externalPort.b[1] = *data++;
ttl = get_uint32(&data, end);
if (!data) goto fail;
((DNSServiceNATPortMappingReply)sdr->AppCallback)(sdr, cbh->cb_flags, cbh->cb_interface, cbh->cb_err, addr.l, protocol, internalPort.s, externalPort.s, ttl, sdr->AppContext);
return;
// MUST NOT touch sdr after invoking AppCallback -- client is allowed to dispose it from within callback function
fail :
syslog(LOG_WARNING, "dnssd_clientstub handle_port_mapping_response: error reading result from daemon");
}
DNSServiceErrorType DNSSD_API DNSServiceNATPortMappingCreate
(
DNSServiceRef *sdRef,
DNSServiceFlags flags,
uint32_t interfaceIndex,
uint32_t protocol, /* TCP and/or UDP */
uint16_t internalPortInNetworkByteOrder,
uint16_t externalPortInNetworkByteOrder,
uint32_t ttl, /* time to live in seconds */
DNSServiceNATPortMappingReply callBack,
void *context /* may be NULL */
)
{
char *ptr;
size_t len;
ipc_msg_hdr *hdr;
union { uint16_t s; u_char b[2]; } internalPort = { internalPortInNetworkByteOrder };
union { uint16_t s; u_char b[2]; } externalPort = { externalPortInNetworkByteOrder };
DNSServiceErrorType err = ConnectToServer(sdRef, flags, port_mapping_request, handle_port_mapping_response, callBack, context);
if (err) return err; // On error ConnectToServer leaves *sdRef set to NULL
len = sizeof(flags);
len += sizeof(interfaceIndex);
len += sizeof(protocol);
len += sizeof(internalPort);
len += sizeof(externalPort);
len += sizeof(ttl);
hdr = create_hdr(port_mapping_request, &len, &ptr, (*sdRef)->primary ? 1 : 0, *sdRef);
if (!hdr) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; return kDNSServiceErr_NoMemory; }
put_flags(flags, &ptr);
put_uint32(interfaceIndex, &ptr);
put_uint32(protocol, &ptr);
*ptr++ = internalPort.b[0];
*ptr++ = internalPort.b[1];
*ptr++ = externalPort.b[0];
*ptr++ = externalPort.b[1];
put_uint32(ttl, &ptr);
err = deliver_request(hdr, *sdRef); // Will free hdr for us
if (err) { DNSServiceRefDeallocate(*sdRef); *sdRef = NULL; }
return err;
}
#if _DNS_SD_LIBDISPATCH
DNSServiceErrorType DNSSD_API DNSServiceSetDispatchQueue
(
DNSServiceRef service,
dispatch_queue_t queue
)
{
int dnssd_fd = DNSServiceRefSockFD(service);
if (dnssd_fd == dnssd_InvalidSocket) return kDNSServiceErr_BadParam;
if (!queue)
{
syslog(LOG_WARNING, "dnssd_clientstub: DNSServiceSetDispatchQueue dispatch queue NULL");
return kDNSServiceErr_BadParam;
}
if (service->disp_queue)
{
syslog(LOG_WARNING, "dnssd_clientstub DNSServiceSetDispatchQueue dispatch queue set already");
return kDNSServiceErr_BadParam;
}
if (service->disp_source)
{
syslog(LOG_WARNING, "DNSServiceSetDispatchQueue dispatch source set already");
return kDNSServiceErr_BadParam;
}
service->disp_source = dispatch_source_create(DISPATCH_SOURCE_TYPE_READ, dnssd_fd, 0, queue);
if (!service->disp_source)
{
syslog(LOG_WARNING, "DNSServiceSetDispatchQueue dispatch_source_create failed");
return kDNSServiceErr_NoMemory;
}
service->disp_queue = queue;
dispatch_source_set_event_handler(service->disp_source, ^{DNSServiceProcessResult(service);});
dispatch_source_set_cancel_handler(service->disp_source, ^{dnssd_close(dnssd_fd);});
dispatch_resume(service->disp_source);
return kDNSServiceErr_NoError;
}
#endif // _DNS_SD_LIBDISPATCH
#if !defined(_WIN32)
static void DNSSD_API SleepKeepaliveCallback(DNSServiceRef sdRef, DNSRecordRef rec, const DNSServiceFlags flags,
DNSServiceErrorType errorCode, void *context)
{
SleepKAContext *ka = (SleepKAContext *)context;
(void)rec; // Unused
(void)flags; // Unused
if (sdRef->kacontext != context)
syslog(LOG_WARNING, "SleepKeepaliveCallback context mismatch");
if (ka->AppCallback)
((DNSServiceSleepKeepaliveReply)ka->AppCallback)(sdRef, errorCode, ka->AppContext);
}
DNSServiceErrorType DNSSD_API DNSServiceSleepKeepalive
(
DNSServiceRef *sdRef,
DNSServiceFlags flags,
int fd,
unsigned int timeout,
DNSServiceSleepKeepaliveReply callBack,
void *context
)
{
char source_str[INET6_ADDRSTRLEN];
char target_str[INET6_ADDRSTRLEN];
struct sockaddr_storage lss;
struct sockaddr_storage rss;
socklen_t len1, len2;
unsigned int len, proxyreclen;
char buf[256];
DNSServiceErrorType err;
DNSRecordRef record = NULL;
char name[10];
char recname[128];
SleepKAContext *ka;
unsigned int i, unique;
(void) flags; //unused
if (!timeout) return kDNSServiceErr_BadParam;
len1 = sizeof(lss);
if (getsockname(fd, (struct sockaddr *)&lss, &len1) < 0)
{
syslog(LOG_WARNING, "DNSServiceSleepKeepalive: getsockname %d\n", errno);
return kDNSServiceErr_BadParam;
}
len2 = sizeof(rss);
if (getpeername(fd, (struct sockaddr *)&rss, &len2) < 0)
{
syslog(LOG_WARNING, "DNSServiceSleepKeepalive: getpeername %d\n", errno);
return kDNSServiceErr_BadParam;
}
if (len1 != len2)
{
syslog(LOG_WARNING, "DNSServiceSleepKeepalive local/remote info not same");
return kDNSServiceErr_Unknown;
}
unique = 0;
if (lss.ss_family == AF_INET)
{
struct sockaddr_in *sl = (struct sockaddr_in *)&lss;
struct sockaddr_in *sr = (struct sockaddr_in *)&rss;
unsigned char *ptr = (unsigned char *)&sl->sin_addr;
if (!inet_ntop(AF_INET, (const void *)&sr->sin_addr, target_str, sizeof (target_str)))
{
syslog(LOG_WARNING, "DNSServiceSleepKeepalive remote info failed %d", errno);
return kDNSServiceErr_Unknown;
}
if (!inet_ntop(AF_INET, (const void *)&sl->sin_addr, source_str, sizeof (source_str)))
{
syslog(LOG_WARNING, "DNSServiceSleepKeepalive local info failed %d", errno);
return kDNSServiceErr_Unknown;
}
// Sum of all bytes in the local address and port should result in a unique
// number in the local network
for (i = 0; i < sizeof(struct in_addr); i++)
unique += ptr[i];
unique += sl->sin_port;
len = snprintf(buf+1, sizeof(buf) - 1, "t=%u h=%s d=%s l=%u r=%u", timeout, source_str, target_str, ntohs(sl->sin_port), ntohs(sr->sin_port));
}
else
{
struct sockaddr_in6 *sl6 = (struct sockaddr_in6 *)&lss;
struct sockaddr_in6 *sr6 = (struct sockaddr_in6 *)&rss;
unsigned char *ptr = (unsigned char *)&sl6->sin6_addr;
if (!inet_ntop(AF_INET6, (const void *)&sr6->sin6_addr, target_str, sizeof (target_str)))
{
syslog(LOG_WARNING, "DNSServiceSleepKeepalive remote6 info failed %d", errno);
return kDNSServiceErr_Unknown;
}
if (!inet_ntop(AF_INET6, (const void *)&sl6->sin6_addr, source_str, sizeof (source_str)))
{
syslog(LOG_WARNING, "DNSServiceSleepKeepalive local6 info failed %d", errno);
return kDNSServiceErr_Unknown;
}
for (i = 0; i < sizeof(struct in6_addr); i++)
unique += ptr[i];
unique += sl6->sin6_port;
len = snprintf(buf+1, sizeof(buf) - 1, "t=%u H=%s D=%s l=%u r=%u", timeout, source_str, target_str, ntohs(sl6->sin6_port), ntohs(sr6->sin6_port));
}
if (len >= (sizeof(buf) - 1))
{
syslog(LOG_WARNING, "DNSServiceSleepKeepalive could not fit local/remote info");
return kDNSServiceErr_Unknown;
}
// Include the NULL byte also in the first byte. The total length of the record includes the
// first byte also.
buf[0] = len + 1;
proxyreclen = len + 2;
len = snprintf(name, sizeof(name), "%u", unique);
if (len >= sizeof(name))
{
syslog(LOG_WARNING, "DNSServiceSleepKeepalive could not fit unique");
return kDNSServiceErr_Unknown;
}
len = snprintf(recname, sizeof(recname), "%s.%s", name, "_keepalive._dns-sd._udp.local");
if (len >= sizeof(recname))
{
syslog(LOG_WARNING, "DNSServiceSleepKeepalive could not fit name");
return kDNSServiceErr_Unknown;
}
ka = malloc(sizeof(SleepKAContext));
if (!ka) return kDNSServiceErr_NoMemory;
ka->AppCallback = callBack;
ka->AppContext = context;
err = DNSServiceCreateConnection(sdRef);
if (err)
{
syslog(LOG_WARNING, "DNSServiceSleepKeepalive cannot create connection");
free(ka);
return err;
}
// we don't care about the "record". When sdRef gets deallocated later, it will be freed too
err = DNSServiceRegisterRecord(*sdRef, &record, kDNSServiceFlagsUnique, 0, recname,
kDNSServiceType_NULL, kDNSServiceClass_IN, proxyreclen, buf, kDNSServiceInterfaceIndexAny, SleepKeepaliveCallback, ka);
if (err)
{
syslog(LOG_WARNING, "DNSServiceSleepKeepalive cannot create connection");
free(ka);
return err;
}
(*sdRef)->kacontext = ka;
return kDNSServiceErr_NoError;
}
#endif
