kio

discovery.cpp

00001 /*
00002    Copyright (c) 2003 Malte Starostik <malte@kde.org>
00003 
00004    This library is free software; you can redistribute it and/or
00005    modify it under the terms of the GNU Library General Public
00006    License as published by the Free Software Foundation; either
00007    version 2 of the License, or (at your option) any later version.
00008 
00009    This library is distributed in the hope that it will be useful,
00010    but WITHOUT ANY WARRANTY; without even the implied warranty of
00011    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00012    Library General Public License for more details.
00013 
00014    You should have received a copy of the GNU Library General Public License
00015    along with this library; see the file COPYING.LIB.  If not, write to
00016    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
00017    Boston, MA 02110-1301, USA.
00018 */
00019 
00020 
00021 #include "config.h"
00022 
00023 #include <netdb.h>
00024 
00025 #ifdef HAVE_SYS_TYPES_H
00026 #include <sys/types.h>
00027 #endif
00028 #ifdef HAVE_NETINET_IN_H
00029 #include <netinet/in.h>
00030 #endif
00031 #include <arpa/nameser.h>
00032 #ifdef HAVE_ARPA_NAMESER8_COMPAT_H
00033 #include <arpa/nameser8_compat.h>
00034 #endif
00035 #ifdef HAVE_SYS_PARAM_H
00036 // Basically, the BSDs need this before resolv.h
00037 #include <sys/param.h>
00038 #endif
00039 #include <resolv.h>
00040 #include <sys/utsname.h>
00041 
00042 #include <qtimer.h>
00043 
00044 #include <klocale.h>
00045 #include <kprocio.h>
00046 #include <kurl.h>
00047 
00048 #include "discovery.moc"
00049 
00050 namespace KPAC
00051 {
00052     Discovery::Discovery( QObject* parent )
00053         : Downloader( parent ),
00054           m_helper( new KProcIO )
00055     {
00056         connect( m_helper, SIGNAL( readReady( KProcIO* ) ), SLOT( helperOutput() ) );
00057         connect( m_helper, SIGNAL( processExited( KProcess* ) ), SLOT( failed() ) );
00058         *m_helper << "kpac_dhcp_helper";
00059 
00060         if ( !m_helper->start() )
00061             QTimer::singleShot( 0, this, SLOT( failed() ) );
00062     }
00063 
00064     bool Discovery::initHostName()
00065     {
00066         struct utsname uts;
00067 
00068         if (uname (&uts) > -1)
00069         {
00070             struct hostent *hent = gethostbyname (uts.nodename);
00071             if (hent != 0)
00072                 m_hostname = QString::fromLocal8Bit( hent->h_name );
00073         }
00074 
00075         // If no hostname, try gethostname as a last resort.
00076         if (m_hostname.isEmpty())
00077         {
00078             char buf [256];
00079             if (gethostname (buf, sizeof(buf)) == 0)
00080             {
00081                 buf[255] = '\0';
00082                 m_hostname = QString::fromLocal8Bit( buf );
00083             }
00084         }
00085         return !m_hostname.isEmpty();
00086     }
00087 
00088     bool Discovery::checkDomain() const
00089     {
00090         // If a domain has a SOA record, don't traverse any higher.
00091         // Returns true if no SOA can be found (domain is "ok" to use)
00092         // Stick to old resolver interface for portability reasons.
00093         union
00094         {
00095             HEADER header;
00096             unsigned char buf[ PACKETSZ ];
00097         } response;
00098         int len = res_query( m_hostname.local8Bit(), C_IN, T_SOA,
00099                              response.buf, sizeof( response.buf ) );
00100         if ( len <= int( sizeof( response.header ) ) ||
00101              ntohs( response.header.ancount ) != 1 ) return true;
00102         unsigned char* pos = response.buf + sizeof( response.header );
00103         unsigned char* end = response.buf + len;
00104         // skip query section
00105         pos += dn_skipname( pos, end ) + QFIXEDSZ;
00106         if ( pos >= end ) return true;
00107         // skip answer domain
00108         pos += dn_skipname( pos, end );
00109         short type;
00110         GETSHORT( type, pos );
00111         return type != T_SOA;
00112     }
00113 
00114     void Discovery::failed()
00115     {
00116         setError( i18n( "Could not find a usable proxy configuration script" ) );
00117 
00118         // If this is the first DNS query, initialize our host name or abort
00119         // on failure. Otherwise abort if the current domain (which was already
00120         // queried for a host called "wpad" contains a SOA record)
00121         bool firstQuery = m_hostname.isEmpty();
00122         if ( ( firstQuery && !initHostName() ) ||
00123              ( !firstQuery && !checkDomain() ) )
00124         {
00125             emit result( false );
00126             return;
00127         }
00128 
00129         int dot = m_hostname.find( '.' );
00130         if ( dot >= 0 )
00131         {
00132             m_hostname.remove( 0, dot + 1 ); // remove one domain level
00133             download( KURL( "http://wpad." + m_hostname + "./wpad.dat" ) );
00134         }
00135         else emit result( false );
00136     }
00137 
00138     void Discovery::helperOutput()
00139     {
00140         m_helper->disconnect( this );
00141         QString line;
00142         m_helper->readln( line );
00143         download( KURL( line.stripWhiteSpace() ) );
00144     }
00145 }
00146 
00147 // vim: ts=4 sw=4 et
kio

discovery.cpp

kio

API Reference
