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     2 **

     3 ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).

     4 ** All rights reserved.

     5 ** Contact: Nokia Corporation (qt-info@nokia.com)

     6 **

     7 ** This file is part of the QtNetwork module of the Qt Toolkit.

     8 **

     9 ** $QT_BEGIN_LICENSE:LGPL$

    10 ** No Commercial Usage

    11 ** This file contains pre-release code and may not be distributed.

    12 ** You may use this file in accordance with the terms and conditions

    13 ** contained in the Technology Preview License Agreement accompanying

    14 ** this package.

    15 **

    16 ** GNU Lesser General Public License Usage

    17 ** Alternatively, this file may be used under the terms of the GNU Lesser

    18 ** General Public License version 2.1 as published by the Free Software

    19 ** Foundation and appearing in the file LICENSE.LGPL included in the

    20 ** packaging of this file.  Please review the following information to

    21 ** ensure the GNU Lesser General Public License version 2.1 requirements

    22 ** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.

    23 **

    24 ** In addition, as a special exception, Nokia gives you certain additional

    25 ** rights.  These rights are described in the Nokia Qt LGPL Exception

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    28 ** If you have questions regarding the use of this file, please contact

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    36 **

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    38 ** $QT_END_LICENSE$

    39 **

    40 ****************************************************************************/

    41 

    42 //#define QHOSTINFO_DEBUG

    43 

    44 #include "qplatformdefs.h"

    45 

    46 #include "qhostinfo_p.h"

    47 #include "qiodevice.h"

    48 #include <qbytearray.h>

    49 #include <qlibrary.h>

    50 #include <qurl.h>

    51 #include <qfile.h>

    52 #include <private/qmutexpool_p.h>

    53 #include <private/qnet_unix_p.h>

    54 

    55 #include <sys/types.h>

    56 #include <netdb.h>

    57 #include <arpa/inet.h>

    58 #if defined(Q_OS_VXWORKS)

    59 #  include <hostLib.h>

    60 #else

    61 #  include <resolv.h>

    62 #endif

    63 

    64 #if defined (QT_NO_GETADDRINFO)

    65 #include <qmutex.h>

    66 QT_BEGIN_NAMESPACE

    67 Q_GLOBAL_STATIC(QMutex, getHostByNameMutex)

    68 QT_END_NAMESPACE

    69 #endif

    70 

    71 QT_BEGIN_NAMESPACE

    72 

    73 // Almost always the same. If not, specify in qplatformdefs.h.

    74 #if !defined(QT_SOCKOPTLEN_T)

    75 # define QT_SOCKOPTLEN_T QT_SOCKLEN_T

    76 #endif

    77 

    78 // HP-UXi has a bug in getaddrinfo(3) that makes it thread-unsafe

    79 // with this flag. So disable it in that platform.

    80 #if defined(AI_ADDRCONFIG) && !defined(Q_OS_HPUX)

    81 #  define Q_ADDRCONFIG          AI_ADDRCONFIG

    82 #endif

    83 

    84 typedef struct __res_state *res_state_ptr;

    85 

    86 typedef int (*res_init_proto)(void);

    87 static res_init_proto local_res_init = 0;

    88 typedef int (*res_ninit_proto)(res_state_ptr);

    89 static res_ninit_proto local_res_ninit = 0;

    90 typedef void (*res_nclose_proto)(res_state_ptr);

    91 static res_nclose_proto local_res_nclose = 0;

    92 static res_state_ptr local_res = 0;

    93 

    94 static void resolveLibrary()

    95 {

    96 #ifndef QT_NO_LIBRARY

    97     QLibrary lib(QLatin1String("resolv"));

    98     if (!lib.load())

    99         return;

   100 

   101     local_res_init = res_init_proto(lib.resolve("__res_init"));

   102     if (!local_res_init)

   103         local_res_init = res_init_proto(lib.resolve("res_init"));

   104 

   105     local_res_ninit = res_ninit_proto(lib.resolve("__res_ninit"));

   106     if (!local_res_ninit)

   107         local_res_ninit = res_ninit_proto(lib.resolve("res_ninit"));

   108 

   109     if (!local_res_ninit) {

   110         // if we can't get a thread-safe context, we have to use the global _res state

   111         local_res = res_state_ptr(lib.resolve("_res"));

   112     } else {

   113         local_res_nclose = res_nclose_proto(lib.resolve("res_nclose"));

   114         if (!local_res_nclose)

   115             local_res_nclose = res_nclose_proto(lib.resolve("__res_nclose"));

   116         if (!local_res_nclose)

   117             local_res_ninit = 0;

   118     }

   119 #endif

   120 }

   121 

   122 QHostInfo QHostInfoAgent::fromName(const QString &hostName)

   123 {

   124     QHostInfo results;

   125 

   126 #if defined(QHOSTINFO_DEBUG)

   127     qDebug("QHostInfoAgent::fromName(%s) looking up...",

   128            hostName.toLatin1().constData());

   129 #endif

   130 

   131     // Load res_init on demand.

   132     static volatile bool triedResolve = false;

   133     if (!triedResolve) {

   134 #ifndef QT_NO_THREAD

   135         QMutexLocker locker(QMutexPool::globalInstanceGet(&local_res_init));

   136 #endif

   137         if (!triedResolve) {

   138             resolveLibrary();

   139             triedResolve = true;

   140         }

   141     }

   142 

   143     // If res_init is available, poll it.

   144     if (local_res_init)

   145         local_res_init();

   146 

   147     QHostAddress address;

   148     if (address.setAddress(hostName)) {

   149         // Reverse lookup

   150 // Reverse lookups using getnameinfo are broken on darwin, use gethostbyaddr instead.

   151 #if !defined (QT_NO_GETADDRINFO) && !defined (Q_OS_DARWIN) && !defined (Q_OS_SYMBIAN)

   152         sockaddr_in sa4;

   153 #ifndef QT_NO_IPV6

   154         sockaddr_in6 sa6;

   155 #endif

   156         sockaddr *sa = 0;

   157         QT_SOCKLEN_T saSize = 0;

   158         if (address.protocol() == QAbstractSocket::IPv4Protocol) {

   159             sa = (sockaddr *)&sa4;

   160             saSize = sizeof(sa4);

   161             memset(&sa4, 0, sizeof(sa4));

   162             sa4.sin_family = AF_INET;

   163             sa4.sin_addr.s_addr = htonl(address.toIPv4Address());

   164         }

   165 #ifndef QT_NO_IPV6

   166         else {

   167             sa = (sockaddr *)&sa6;

   168             saSize = sizeof(sa6);

   169             memset(&sa6, 0, sizeof(sa6));

   170             sa6.sin6_family = AF_INET6;

   171             memcpy(sa6.sin6_addr.s6_addr, address.toIPv6Address().c, sizeof(sa6.sin6_addr.s6_addr));

   172         }

   173 #endif

   174 

   175         char hbuf[NI_MAXHOST];

   176         if (sa && getnameinfo(sa, saSize, hbuf, sizeof(hbuf), 0, 0, 0) == 0)

   177             results.setHostName(QString::fromLatin1(hbuf));

   178 #else

   179         in_addr_t inetaddr = qt_safe_inet_addr(hostName.toLatin1().constData());

   180         struct hostent *ent = gethostbyaddr((const char *)&inetaddr, sizeof(inetaddr), AF_INET);

   181         if (ent)

   182             results.setHostName(QString::fromLatin1(ent->h_name));

   183 #endif

   184 

   185         if (results.hostName().isEmpty())

   186             results.setHostName(address.toString());

   187         results.setAddresses(QList<QHostAddress>() << address);

   188         return results;

   189     }

   190 

   191     // IDN support

   192     QByteArray aceHostname = QUrl::toAce(hostName);

   193     results.setHostName(hostName);

   194     if (aceHostname.isEmpty()) {

   195         results.setError(QHostInfo::HostNotFound);

   196         results.setErrorString(hostName.isEmpty() ? QObject::tr("No host name given") : QObject::tr("Invalid hostname"));

   197         return results;

   198     }

   199 

   200 #if !defined (QT_NO_GETADDRINFO)

   201     // Call getaddrinfo, and place all IPv4 addresses at the start and

   202     // the IPv6 addresses at the end of the address list in results.

   203     addrinfo *res = 0;

   204     struct addrinfo hints;

   205     memset(&hints, 0, sizeof(hints));

   206     hints.ai_family = PF_UNSPEC;

   207 #ifdef Q_ADDRCONFIG

   208     hints.ai_flags = Q_ADDRCONFIG;

   209 #endif

   210 

   211     int result = getaddrinfo(aceHostname.constData(), 0, &hints, &res);

   212 # ifdef Q_ADDRCONFIG

   213     if (result == EAI_BADFLAGS) {

   214         // if the lookup failed with AI_ADDRCONFIG set, try again without it

   215         hints.ai_flags = 0;

   216         result = getaddrinfo(aceHostname.constData(), 0, &hints, &res);

   217     }

   218 # endif

   219 

   220     if (result == 0) {

   221         addrinfo *node = res;

   222         QList<QHostAddress> addresses;

   223         while (node) {

   224             if (node->ai_family == AF_INET) {

   225                 QHostAddress addr;

   226                 addr.setAddress(ntohl(((sockaddr_in *) node->ai_addr)->sin_addr.s_addr));

   227                 if (!addresses.contains(addr))

   228                     addresses.append(addr);

   229             }

   230 #ifndef QT_NO_IPV6

   231             else if (node->ai_family == AF_INET6) {

   232                 QHostAddress addr;

   233                 addr.setAddress(((sockaddr_in6 *) node->ai_addr)->sin6_addr.s6_addr);

   234                 if (!addresses.contains(addr))

   235                     addresses.append(addr);

   236             }

   237 #endif

   238             node = node->ai_next;

   239         }

   240         if (addresses.isEmpty() && node == 0) {

   241             // Reached the end of the list, but no addresses were found; this

   242             // means the list contains one or more unknown address types.

   243             results.setError(QHostInfo::UnknownError);

   244             results.setErrorString(tr("Unknown address type"));

   245         }

   246 

   247         results.setAddresses(addresses);

   248         freeaddrinfo(res);

   249     } else if (result == EAI_NONAME

   250                || result ==  EAI_FAIL

   251 #ifdef EAI_NODATA

   252 	       // EAI_NODATA is deprecated in RFC 3493

   253 	       || result == EAI_NODATA

   254 #endif

   255 	       ) {

   256         results.setError(QHostInfo::HostNotFound);

   257         results.setErrorString(tr("Host not found"));

   258     } else {

   259         results.setError(QHostInfo::UnknownError);

   260         results.setErrorString(QString::fromLocal8Bit(gai_strerror(result)));

   261     }

   262 

   263 #else

   264     // Fall back to gethostbyname for platforms that don't define

   265     // getaddrinfo. gethostbyname does not support IPv6, and it's not

   266     // reentrant on all platforms. For now this is okay since we only

   267     // use one QHostInfoAgent, but if more agents are introduced, locking

   268     // must be provided.

   269     QMutexLocker locker(::getHostByNameMutex());

   270     hostent *result = gethostbyname(aceHostname.constData());

   271     if (result) {

   272         if (result->h_addrtype == AF_INET) {

   273             QList<QHostAddress> addresses;

   274             for (char **p = result->h_addr_list; *p != 0; p++) {

   275                 QHostAddress addr;

   276                 addr.setAddress(ntohl(*((quint32 *)*p)));

   277                 if (!addresses.contains(addr))

   278                     addresses.prepend(addr);

   279             }

   280             results.setAddresses(addresses);

   281         } else {

   282             results.setError(QHostInfo::UnknownError);

   283             results.setErrorString(tr("Unknown address type"));

   284         }

   285 #if !defined(Q_OS_VXWORKS)

   286     } else if (h_errno == HOST_NOT_FOUND || h_errno == NO_DATA

   287                || h_errno == NO_ADDRESS) {

   288         results.setError(QHostInfo::HostNotFound);

   289         results.setErrorString(tr("Host not found"));

   290 #endif

   291     } else {

   292         results.setError(QHostInfo::UnknownError);

   293         results.setErrorString(tr("Unknown error"));

   294     }

   295 #endif //  !defined (QT_NO_GETADDRINFO)

   296 

   297 #if defined(QHOSTINFO_DEBUG)

   298     if (results.error() != QHostInfo::NoError) {

   299         qDebug("QHostInfoAgent::fromName(): error #%d %s",

   300                h_errno, results.errorString().toLatin1().constData());

   301     } else {

   302         QString tmp;

   303         QList<QHostAddress> addresses = results.addresses();

   304         for (int i = 0; i < addresses.count(); ++i) {

   305             if (i != 0) tmp += ", ";

   306             tmp += addresses.at(i).toString();

   307         }

   308         qDebug("QHostInfoAgent::fromName(): found %i entries for \"%s\": {%s}",

   309                addresses.count(), hostName.toLatin1().constData(),

   310                tmp.toLatin1().constData());

   311     }

   312 #endif

   313     return results;

   314 }

   315 

   316 QString QHostInfo::localHostName()

   317 {

   318     char hostName[512];

   319     if (gethostname(hostName, sizeof(hostName)) == -1)

   320         return QString();

   321     hostName[sizeof(hostName) - 1] = '\0';

   322     return QString::fromLocal8Bit(hostName);

   323 }

   324 

   325 QString QHostInfo::localDomainName()

   326 {

   327 #if !defined(Q_OS_VXWORKS)

   328     resolveLibrary();

   329     if (local_res_ninit) {

   330         // using thread-safe version

   331         res_state_ptr state = res_state_ptr(qMalloc(sizeof(*state)));

   332         Q_CHECK_PTR(state);

   333         memset(state, 0, sizeof(*state));

   334         local_res_ninit(state);

   335         QString domainName = QUrl::fromAce(state->defdname);

   336         if (domainName.isEmpty())

   337             domainName = QUrl::fromAce(state->dnsrch[0]);

   338         local_res_nclose(state);

   339         qFree(state);

   340 

   341         return domainName;

   342     }

   343 

   344     if (local_res_init && local_res) {

   345         // using thread-unsafe version

   346 

   347 #if defined(QT_NO_GETADDRINFO)

   348         // We have to call res_init to be sure that _res was initialized

   349         // So, for systems without getaddrinfo (which is thread-safe), we lock the mutex too

   350         QMutexLocker locker(::getHostByNameMutex());

   351 #endif

   352         local_res_init();

   353         QString domainName = QUrl::fromAce(local_res->defdname);

   354         if (domainName.isEmpty())

   355             domainName = QUrl::fromAce(local_res->dnsrch[0]);

   356         return domainName;

   357     }

   358 #endif

   359     // nothing worked, try doing it by ourselves:

   360     QFile resolvconf;

   361 #if defined(_PATH_RESCONF)

   362     resolvconf.setFileName(QFile::decodeName(_PATH_RESCONF));

   363 #else

   364     resolvconf.setFileName(QLatin1String("/etc/resolv.conf"));

   365 #endif

   366     if (!resolvconf.open(QIODevice::ReadOnly))

   367         return QString();       // failure

   368 

   369     QString domainName;

   370     while (!resolvconf.atEnd()) {

   371         QByteArray line = resolvconf.readLine().trimmed();

   372         if (line.startsWith("domain "))

   373             return QUrl::fromAce(line.mid(sizeof "domain " - 1).trimmed());

   374 

   375         // in case there's no "domain" line, fall back to the first "search" entry

   376         if (domainName.isEmpty() && line.startsWith("search ")) {

   377             QByteArray searchDomain = line.mid(sizeof "search " - 1).trimmed();

   378             int pos = searchDomain.indexOf(' ');

   379             if (pos != -1)

   380                 searchDomain.truncate(pos);

   381             domainName = QUrl::fromAce(searchDomain);

   382         }

   383     }

   384 

   385     // return the fallen-back-to searched domain

   386     return domainName;

   387 }

   388 

   389 QT_END_NAMESPACE