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#include <signal.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdio.h>
#include <sys/ioctl.h>
#include "nu_header.h"
static void bailout( char *reason );
static mainsock = -1;
static childsock = -1;
static void netbios_read( SMB_HEADER **buf) {
BYTE bytes[4];
ssize_t bytesread, bytestoread;
if( read( childsock, bytes, 4) < 4 )
bailout( "Short read." );
bytestoread = htons(*(WORD*)(2+bytes));
if( (*buf = (SMB_HEADER*)realloc( *buf, 4 + bytestoread )) == NULL)
bailout( "Out of memory");
*(DWORD*)*buf = *(DWORD*)bytes;
bytesread = read( childsock, ((BYTE*)buf) + 4, bytestoread);
if( bytesread != bytestoread )
bailout( "Short read." );
}
static void netbios_write( BYTE command, BYTE *buf, WORD size ) {
BYTE netbios_header[4] = { command, 0, size >> 8, size & 255 };
if( write( childsock, netbios_header, 4 ) <= 0 ||
write( childsock, buf, size ) < 0 )
bailout( "Write failed." );
}
static void child( ) {
SMB_HEADER *inpacket = NULL;
DWORD bytesread;
/* I should spare that code... */
if( mainsock != -1 ) { close( mainsock ); mainsock = -1; }
/* Try to answer first netbios packet */
netbios_read( &inpacket );
if( inpacket->netbios_command != 0x81 )
bailout( "No session request");
netbios_write( 0x82, NULL, 0 );
while( 1 ) {
netbios_read( &inpacket );
if( inpacket->netbios_command != 0 )
bailout( "Unhandled netbios command" );
if( inpacket->Protocol != SMB_HEADER_PROTOCOL_MAGIC )
bailout( "Protocol identifier mismatch");
switch( inpacket->Command ) {
case SMB_COM_NEGOTIATE:
{
BYTE outblock[5] = { 0xff,0,0,0,0 };
netbios_write( 0, outblock, sizeof( outblock ));
break;
}
default:
{
fprintf( stderr, "Got message: %02X\n", inpacket->Command );
break;
}
}
} /* End main loop */
}
void sigint( int reason ) { bailout( "User interrupt." ); }
int main()
{
struct sockaddr_in sa;
int l=1;
signal( SIGINT, sigint);
bzero( &sa, sizeof( sa));
sa.sin_family = PF_INET;
sa.sin_port = htons( 139 );
sa.sin_addr.s_addr = INADDR_ANY;
if( ( mainsock = socket( PF_INET, SOCK_STREAM, 0) ) == -1)
bailout( "Could not open socket");
setsockopt( mainsock, SOL_SOCKET, SO_REUSEPORT, &l, sizeof(l));
if( bind( mainsock, (struct sockaddr *)&sa, sizeof( sa)) != 0)
bailout( "Could not bind socket");
if( listen( mainsock, 1024) != 0 )
bailout( "Could not make socket listen");
while( 1 ) {
struct sockaddr otherend;
int size = sizeof( otherend );
if( ( childsock = accept( mainsock, &otherend, &size) ) == -1)
bailout( "Socket Broke.");
if (!fork()) child( );
}
}
/* Graceful exit. */
static void bailout( char *reason) {
fputs( reason, stderr);
fputs( "\nCleaning up.\n", stderr);
if( mainsock != -1 )
close( mainsock );
if( childsock != -1 ) {
shutdown( childsock, SHUT_RDWR);
close( childsock );
}
exit( 0 );
}
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