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/*
* Copyright (C) 2008-2010 The QXmpp developers
*
* Author:
* Jeremy Lainé
*
* Source:
* http://code.google.com/p/qxmpp
*
* This file is a part of QXmpp library.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
*/
#include <QDebug>
#include "QXmppServiceInfo.h"
#ifdef Q_OS_WIN
#include <windows.h>
#include <windns.h>
#else
#include <sys/types.h>
#include <netinet/in.h>
#include <netdb.h>
#include <arpa/nameser.h>
#include <arpa/nameser_compat.h>
#include <resolv.h>
#endif
QString QXmppServiceInfo::hostName() const
{
return host_name;
}
quint16 QXmppServiceInfo::port() const
{
return host_port;
}
void QXmppServiceInfo::setHostName(const QString &hostName)
{
host_name = hostName;
}
void QXmppServiceInfo::setPort(quint16 port)
{
host_port = port;
}
/// Perform a DNS lookup for an SRV entry.
///
/// Returns true if the lookup was succesful, false if it failed.
///
/// \param dname
/// \param results
bool QXmppServiceInfo::lookupService(const QString &dname, QList<QXmppServiceInfo> &results)
{
#ifdef Q_OS_WIN
PDNS_RECORD records, ptr;
/* perform DNS query */
if (DnsQuery_UTF8(dname.toAscii(), DNS_TYPE_SRV, DNS_QUERY_STANDARD, NULL, &records, NULL) != ERROR_SUCCESS)
{
qWarning() << "SRV lookup for" << dname << "failed";
return false;
}
/* extract results */
for (ptr = records; ptr != NULL; ptr = ptr->pNext)
{
if ((ptr->wType == DNS_TYPE_SRV) && !strcmp(ptr->pName, dname.toAscii()))
{
QXmppServiceInfo info;
info.setHostName(ptr->Data.Srv.pNameTarget);
info.setPort(ptr->Data.Srv.wPort);
results.append(info);
}
}
DnsRecordListFree(records, DnsFreeRecordList);
#else
unsigned char response[PACKETSZ];
int responseLength, answerCount, answerIndex;
/* explicitly call res_init in case config changed */
res_init();
/* perform DNS query */
memset(response, 0, sizeof(response));
responseLength = res_query(dname.toAscii(), C_IN, T_SRV, response, sizeof(response));
if (responseLength < int(sizeof(HEADER)))
{
qWarning() << "SRV lookup for" << dname << "failed";
herror("SRV lookup error");
return false;
}
/* check the response header */
HEADER *header = (HEADER*)response;
if (header->rcode != NOERROR || !(answerCount = ntohs(header->ancount)))
{
qWarning() << "SRV lookup for" << dname << "returned an error";
return false;
}
/* skip the query */
char host[PACKETSZ], answer[PACKETSZ];
unsigned char *p = response + sizeof(HEADER);
int status = dn_expand(response, response + responseLength, p, host, sizeof(host));
if (status < 0)
{
qWarning("dn_expand failed");
return false;
}
p += status + 4;
/* parse answers */
answerIndex = 0;
while ((p < response + responseLength) && (answerIndex < answerCount))
{
int type, klass, ttl, size;
status = dn_expand(response, response + responseLength, p, host, sizeof(host));
if (status < 0)
{
qWarning("dn_expand failed");
return false;
}
p += status;
type = (p[0] << 8) | p[1];
p += 2;
klass = (p[0] << 8) | p[1];
p += 2;
ttl = (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3];
p += 4;
size = (p[0] << 8) | p[1];
p += 2;
if (type == T_SRV)
{
quint16 port = (p[4] << 8) | p[5];
status = dn_expand(response, response + responseLength, p + 6, answer, sizeof(answer));
if (status < 0)
{
qWarning("dn_expand failed");
return false;
}
QXmppServiceInfo info;
info.setHostName(answer);
info.setPort(port);
results.append(info);
} else {
qWarning("Unexpected DNS answer type");
}
p += size;
answerIndex++;
}
#endif
return !results.isEmpty();
}
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