DNS::HostMap DNS::resolve( const std::string& service, const std::string& proto,
const std::string& domain, const LogSink& logInstance )
{
const std::string dname = "_" + service + "._" + proto + "." + domain;
bool error = false;
DNS::HostMap servers;
DNS_RECORD* pRecord;
if( DnsQuery( dname.c_str(), DNS_TYPE_SRV, DNS_QUERY_STANDARD, NULL, &pRecord, NULL ) == ERROR_SUCCESS )
{
DNS_RECORD* pRec = pRecord;
do
{
if( pRec->wType == DNS_TYPE_SRV )
{
servers[pRec->Data.SRV.pNameTarget] = pRec->Data.SRV.wPort;
}
pRec = pRec->pNext;
}
while( pRec != NULL );
DnsRecordListFree( pRecord, DnsFreeRecordList );
}
else
error = true;
if( error || !servers.size() )
{
servers = defaultHostMap( domain, logInstance );
}
return servers;
}
void ConnectionSOCKS5Proxy::handleConnect( const ConnectionBase* /*connection*/ )
{
if( m_connection )
{
std::string server = m_server;
int port = m_port;
if( port == -1 )
{
DNS::HostMap servers = DNS::resolve( m_server, m_logInstance );
if( servers.size() )
{
server = (*(servers.begin())).first;
port = (*(servers.begin())).second;
}
}
m_logInstance.log( LogLevelDebug, LogAreaClassConnectionSOCKS5Proxy,
"attempting to negotiate socks5 proxy connection" );
bool auth = !m_proxyUser.empty() && !m_proxyPassword.empty();
char *d = new char[auth ? 4 : 3];
d[0] = 0x05; // SOCKS version 5
if( auth )
{
d[1] = 0x02; // two methods
d[3] = 0x02; // method: username/password auth
}
else
d[1] = 0x01; // one method
d[2] = 0x00; // method: no auth
if( !send( std::string( d, auth ? 4 : 3 ) ) )
{
cleanup();
if( m_handler )
m_handler->handleDisconnect( this, ConnIoError );
}
delete[] d;
}
}
DNS::HostMap DNS::resolve( const std::string& service, const std::string& proto,
const std::string& domain, const LogSink& logInstance )
{
const std::string dname = "_" + service + "._" + proto + "." + domain;
bool error = false;
DNS::HostMap servers;
DNS_RECORD* pRecord = NULL;
DNS_STATUS status = DnsQuery_UTF8( dname.c_str(), DNS_TYPE_SRV, DNS_QUERY_STANDARD, NULL, &pRecord, NULL );
if( status == ERROR_SUCCESS )
{
// NOTE: DnsQuery_UTF8 and DnsQuery_A really should have been defined with
// PDNS_RECORDA instead of PDNS_RECORD, since that's what it is (even with _UNICODE defined).
// We'll correct for that mistake with a cast.
DNS_RECORDA* pRec = (DNS_RECORDA*)pRecord;
do
{
if( pRec->wType == DNS_TYPE_SRV )
{
servers[pRec->Data.SRV.pNameTarget] = pRec->Data.SRV.wPort;
}
pRec = pRec->pNext;
}
while( pRec != NULL );
DnsRecordListFree( pRecord, DnsFreeRecordList );
}
else
{
logInstance.warn( LogAreaClassDns, "DnsQuery_UTF8() failed: " + util::int2string( status ) );
error = true;
}
if( error || !servers.size() )
{
servers = defaultHostMap( domain, logInstance );
}
return servers;
}
void ConnectionSOCKS5Proxy::negotiate()
{
m_s5state = S5StateNegotiating;
char *d = new char[m_ip ? 10 : 6 + m_server.length() + 1];
int pos = 0;
d[pos++] = 0x05; // SOCKS version 5
d[pos++] = 0x01; // command CONNECT
d[pos++] = 0x00; // reserved
int port = m_port;
std::string server = m_server;
if( m_ip ) // IP address
{
d[pos++] = 0x01; // IPv4 address
std::string s;
int j = server.length();
int l = 0;
for( int k = 0; k < j && l < 4; ++k )
{
if( server[k] != '.' )
s += server[k];
if( server[k] == '.' || k == j-1 )
{
d[pos++] = atoi( s.c_str() ) & 0x0FF;
s = "";
++l;
}
}
}
else // hostname
{
if( port == -1 )
{
DNS::HostMap servers = DNS::resolve( m_server, m_logInstance );
if( servers.size() )
{
server = (*(servers.begin())).first;
port = (*(servers.begin())).second;
}
}
d[pos++] = 0x03; // hostname
d[pos++] = m_server.length();
strncpy( d + pos, m_server.c_str(), m_server.length() );
pos += m_server.length();
}
int nport = htons( port );
d[pos++] = nport;
d[pos++] = nport >> 8;
#ifndef _WIN32_WCE
std::ostringstream oss;
oss << "requesting socks5 proxy connection to " << server << ":" << port;
m_logInstance.log( LogLevelDebug, LogAreaClassConnectionSOCKS5Proxy, oss.str() );
#endif
if( !send( std::string( d, pos ) ) )
{
cleanup();
m_handler->handleDisconnect( this, ConnIoError );
}
delete[] d;
}