Hi,
I don't know if I post my request in the correct group.

I try to send a packet with raw socket from a program wrote with c 
langage and compiled on linux os (kernel : 2.4.27-1-386) but I have an 
error with ethereal sniffer on windows xp.

I can't find any solution on the net.   :(    Could anybody help with 
that problem?


my code :

#define __USE_BSD
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#define __FAVOR_BSD
#include <netinet/tcp.h>
#include <unistd.h>
#include <ncurses.h>
#include <stdlib.h>
#include <string.h>


unsigned short        /* this function generates header checksums */
csum (unsigned short *buf, int nwords)
{
   unsigned long sum;
   for (sum = 0; nwords > 0; nwords--)
     sum += *buf++;
   sum = (sum >> 16) + (sum & 0xffff);
   sum += (sum >> 16);
   return ~sum;
}


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

if(argc < 5){
printf("Usage : %s <srcIP> <destIP> <destPORT> <nbDatagram>\n",argv[0]);
printf("Example : %s 192.168.0.140 192.168.0.146 445 5\n",argv[0]);

return -1;
}

char datagram[4096];

struct ip *iph = (struct ip *) datagram;
struct tcphdr *tcph = (struct tcphdr *) datagram + sizeof (struct ip);
struct sockaddr_in sin;


memset (datagram, 0, 4096);    /* zero out the buffer */

sin.sin_family = AF_INET;
sin.sin_addr.s_addr = inet_addr (argv[2]);
sin.sin_port = htons (atoi(argv[3]));

/* we'll now fill in the ip/tcp header values */
   iph->ip_hl = 5;
   iph->ip_v = IPPROTO_IPIP;
   iph->ip_tos = 0;
   iph->ip_len = sizeof (struct ip) + sizeof (struct tcphdr);
   iph->ip_id = htonl (random());
   iph->ip_off = 0;
   iph->ip_ttl = 255;
   iph->ip_p = IPPROTO_TCP;
   iph->ip_sum = 0;
   iph->ip_src.s_addr = inet_addr (argv[1]);
   iph->ip_dst.s_addr = sin.sin_addr.s_addr;

   tcph->th_sport = htons (random());
   tcph->th_dport = sin.sin_port;
   tcph->th_seq = random ();
   tcph->th_ack = 0;
   tcph->th_x2 = 0;
   tcph->th_off = 0; (I tried with tcph->th_off = 5; too)
   tcph->th_flags = TH_SYN;
   tcph->th_win = htonl (65535);
   tcph->th_sum = 0;
   tcph->th_urp = 0;

   iph->ip_sum = csum ((unsigned short *) datagram, iph->ip_len >> 1);


int s = socket (PF_INET, SOCK_RAW, IPPROTO_TCP);    /* open raw socket */

int one = 1;
const int *val = &one;
if (setsockopt (s, IPPROTO_IP, IP_HDRINCL, val, sizeof (one)) < 0)
       printf ("Warning: Cannot set HDRINCL!\n");


int loop = 0;
while (loop<atoi(argv[4]))
{
   loop++;
   if (sendto (s,        /* our socket */
                datagram,    /* the buffer containing headers and data */
          iph->ip_len,    /* total length of our datagram */
          0,        /* routing flags, normally always 0 */
          (struct sockaddr *) &sin,    /* socket addr, just like in */
          sizeof (sin)) < 0)        /* a normal send() */
     printf ("error\n");
    else
     printf (".");
}
return 0;

}

And This is the ethereal's response :

No.     Time        Source                Destination           Protocol 
Info
       1 0.000000    192.168.0.140         192.168.0.146         TCP   0 
 > 0 [] Seq=0 Ack=0 Win=0, bogus TCP header length (0, must be at least 20)

Frame 1 (60 bytes on wire, 60 bytes captured)
Ethernet II, Src: 3com_b6:d6:29 (00:50:da:b6:d6:29), Dst: 
DellComp_d5:be:c6 (00:b0:d0:d5:be:c6)
Internet Protocol, Src: 192.168.0.140 (192.168.0.140), Dst: 
192.168.0.146 (192.168.0.146)
     Version: 4
     Header length: 20 bytes
     Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)
     Total Length: 40
     Identification: 0x0000 (0)
     Flags: 0x04 (Don't Fragment)
     Fragment offset: 0
     Time to live: 255
     Protocol: TCP (0x06)
     Header checksum: 0xf960 [correct]
     Source: 192.168.0.140 (192.168.0.140)
     Destination: 192.168.0.146 (192.168.0.146)
Transmission Control Protocol, Src Port: 0 (0), Dst Port: 0 (0), Seq: 0
     Source port: 0 (0)
     Destination port: 0 (0)
     Sequence number: 0    (relative sequence number)
     Header length: 0 bytes (bogus, must be at least 20)

Tiger wrote:

> I don't know if I post my request in the correct group.

Use Google Groups to find a newsgroup that covers your exact species of 
socket library.

-- 
  Phlip
  http://www.greencheese.org/ZeekLand  <-- NOT a blog!!! 

The TCP header size is 20 bytes, not 5, not 0.

HTH

chris


On Tue, 18 Apr 2006 23:35:01 +0200, Tiger wrote:

> Hi,
> I don't know if I post my request in the correct group.
> 
> I try to send a packet with raw socket from a program wrote with c langage
> and compiled on linux os (kernel : 2.4.27-1-386) but I have an error with
> ethereal sniffer on windows xp.
> 
> I can't find any solution on the net.   :(    Could anybody help with that
> problem?
> 
> 
> my code :
> 
> #define __USE_BSD
> #include <sys/socket.h>
> #include <netinet/in.h>
> #include <netinet/ip.h>
> #define __FAVOR_BSD
> #include <netinet/tcp.h>
> #include <unistd.h>
> #include <ncurses.h>
> #include <stdlib.h>
> #include <string.h>
> 
> 
> unsigned short        /* this function generates header checksums */ csum
> (unsigned short *buf, int nwords) {
>    unsigned long sum;
>    for (sum = 0; nwords > 0; nwords--)
>      sum += *buf++;
>    sum = (sum >> 16) + (sum & 0xffff);
>    sum += (sum >> 16);
>    return ~sum;
> }
> }
> 
> int main (int argc, char *argv[]){
> 
> if(argc < 5){
> printf("Usage : %s <srcIP> <destIP> <destPORT> <nbDatagram>\n",argv[0]);
> printf("Example : %s 192.168.0.140 192.168.0.146 445 5\n",argv[0]);
> 
> return -1;
> }
> }
> char datagram[4096];
> 
> struct ip *iph = (struct ip *) datagram; struct tcphdr *tcph = (struct
> tcphdr *) datagram + sizeof (struct ip); struct sockaddr_in sin;
> 
> 
> memset (datagram, 0, 4096);    /* zero out the buffer */
> 
> sin.sin_family = AF_INET;
> sin.sin_addr.s_addr = inet_addr (argv[2]); sin.sin_port = htons
> (atoi(argv[3]));
> 
> /* we'll now fill in the ip/tcp header values */
>    iph->ip_hl = 5;
>    iph->ip_v = IPPROTO_IPIP;
>    iph->ip_tos = 0;
>    iph->ip_len = sizeof (struct ip) + sizeof (struct tcphdr); iph->ip_id =
>    htonl (random());
>    iph->ip_off = 0;
>    iph->ip_ttl = 255;
>    iph->ip_p = IPPROTO_TCP;
>    iph->ip_sum = 0;
>    iph->ip_src.s_addr = inet_addr (argv[1]); iph->ip_dst.s_addr =
>    sin.sin_addr.s_addr;
> 
>    tcph->th_sport = htons (random());
>    tcph->th_dport = sin.sin_port;
>    tcph->th_seq = random ();
>    tcph->th_ack = 0;
>    tcph->th_x2 = 0;
>    tcph->th_off = 0; (I tried with tcph->th_off = 5; too) tcph->th_flags =
>    TH_SYN;
>    tcph->th_win = htonl (65535);
>    tcph->th_sum = 0;
>    tcph->th_urp = 0;
> 
>    iph->ip_sum = csum ((unsigned short *) datagram, iph->ip_len >> 1);
> 
> 
> int s = socket (PF_INET, SOCK_RAW, IPPROTO_TCP);    /* open raw socket */
> 
> int one = 1;
> const int *val = &one;
> if (setsockopt (s, IPPROTO_IP, IP_HDRINCL, val, sizeof (one)) < 0)
>        printf ("Warning: Cannot set HDRINCL!\n");
> 
> 
> int loop = 0;
> while (loop<atoi(argv[4]))
> {
>    loop++;
>    if (sendto (s,        /* our socket */
>                 datagram,    /* the buffer containing headers and data */
>           iph->ip_len,    /* total length of our datagram */ 0,        /*
>           routing flags, normally always 0 */ (struct sockaddr *) &sin,   
>           /* socket addr, just like in */ sizeof (sin)) < 0)        /* a
>           normal send() */
>      printf ("error\n");
>     else
>      printf (".");
> }
> return 0;
> 
> 
> }
> And This is the ethereal's response :
> 
> No.     Time        Source                Destination           Protocol
> Info
>        1 0.000000    192.168.0.140         192.168.0.146         TCP   0
>  > 0 [] Seq=0 Ack=0 Win=0, bogus TCP header length (0, must be at least
>  > 20)
> 
> Frame 1 (60 bytes on wire, 60 bytes captured) Ethernet II, Src:
> 3com_b6:d6:29 (00:50:da:b6:d6:29), Dst: DellComp_d5:be:c6
> (00:b0:d0:d5:be:c6) Internet Protocol, Src: 192.168.0.140 (192.168.0.140),
> Dst: 192.168.0.146 (192.168.0.146)
>      Version: 4
>      Header length: 20 bytes
>      Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)
>      Total Length: 40
>      Identification: 0x0000 (0)
>      Flags: 0x04 (Don't Fragment)
>      Fragment offset: 0
>      Time to live: 255
>      Protocol: TCP (0x06)
>      Header checksum: 0xf960 [correct]
>      Source: 192.168.0.140 (192.168.0.140) Destination: 192.168.0.146
>      (192.168.0.146)
> Transmission Control Protocol, Src Port: 0 (0), Dst Port: 0 (0), Seq: 0
>      Source port: 0 (0)
>      Destination port: 0 (0)
>      Sequence number: 0    (relative sequence number) Header length: 0
>      bytes (bogus, must be at least 20)

Is that with or without Van Jacobson ?

--
t o b e


gbb wrote:
> The TCP header size is 20 bytes, not 5, not 0.
> 
> HTH
> 
> chris
> 
> 
> On Tue, 18 Apr 2006 23:35:01 +0200, Tiger wrote:
> 
>> Hi,
>> I don't know if I post my request in the correct group.
>>
>> I try to send a packet with raw socket from a program wrote with c langage
>> and compiled on linux os (kernel : 2.4.27-1-386) but I have an error with
>> ethereal sniffer on windows xp.
>>
>> I can't find any solution on the net.   :(    Could anybody help with that
>> problem?
>>
>>
>> my code :
>>
>> #define __USE_BSD
>> #include <sys/socket.h>
>> #include <netinet/in.h>
>> #include <netinet/ip.h>
>> #define __FAVOR_BSD
>> #include <netinet/tcp.h>
>> #include <unistd.h>
>> #include <ncurses.h>
>> #include <stdlib.h>
>> #include <string.h>
>>
>>
>> unsigned short        /* this function generates header checksums */ csum
>> (unsigned short *buf, int nwords) {
>>    unsigned long sum;
>>    for (sum = 0; nwords > 0; nwords--)
>>      sum += *buf++;
>>    sum = (sum >> 16) + (sum & 0xffff);
>>    sum += (sum >> 16);
>>    return ~sum;
>> }
>> }
>>
>> int main (int argc, char *argv[]){
>>
>> if(argc < 5){
>> printf("Usage : %s <srcIP> <destIP> <destPORT> <nbDatagram>\n",argv[0]);
>> printf("Example : %s 192.168.0.140 192.168.0.146 445 5\n",argv[0]);
>>
>> return -1;
>> }
>> }
>> char datagram[4096];
>>
>> struct ip *iph = (struct ip *) datagram; struct tcphdr *tcph = (struct
>> tcphdr *) datagram + sizeof (struct ip); struct sockaddr_in sin;
>>
>>
>> memset (datagram, 0, 4096);    /* zero out the buffer */
>>
>> sin.sin_family = AF_INET;
>> sin.sin_addr.s_addr = inet_addr (argv[2]); sin.sin_port = htons
>> (atoi(argv[3]));
>>
>> /* we'll now fill in the ip/tcp header values */
>>    iph->ip_hl = 5;
>>    iph->ip_v = IPPROTO_IPIP;
>>    iph->ip_tos = 0;
>>    iph->ip_len = sizeof (struct ip) + sizeof (struct tcphdr); iph->ip_id =
>>    htonl (random());
>>    iph->ip_off = 0;
>>    iph->ip_ttl = 255;
>>    iph->ip_p = IPPROTO_TCP;
>>    iph->ip_sum = 0;
>>    iph->ip_src.s_addr = inet_addr (argv[1]); iph->ip_dst.s_addr =
>>    sin.sin_addr.s_addr;
>>
>>    tcph->th_sport = htons (random());
>>    tcph->th_dport = sin.sin_port;
>>    tcph->th_seq = random ();
>>    tcph->th_ack = 0;
>>    tcph->th_x2 = 0;
>>    tcph->th_off = 0; (I tried with tcph->th_off = 5; too) tcph->th_flags =
>>    TH_SYN;
>>    tcph->th_win = htonl (65535);
>>    tcph->th_sum = 0;
>>    tcph->th_urp = 0;
>>
>>    iph->ip_sum = csum ((unsigned short *) datagram, iph->ip_len >> 1);
>>
>>
>> int s = socket (PF_INET, SOCK_RAW, IPPROTO_TCP);    /* open raw socket */
>>
>> int one = 1;
>> const int *val = &one;
>> if (setsockopt (s, IPPROTO_IP, IP_HDRINCL, val, sizeof (one)) < 0)
>>        printf ("Warning: Cannot set HDRINCL!\n");
>>
>>
>> int loop = 0;
>> while (loop<atoi(argv[4]))
>> {
>>    loop++;
>>    if (sendto (s,        /* our socket */
>>                 datagram,    /* the buffer containing headers and data */
>>           iph->ip_len,    /* total length of our datagram */ 0,        /*
>>           routing flags, normally always 0 */ (struct sockaddr *) &sin,   
>>           /* socket addr, just like in */ sizeof (sin)) < 0)        /* a
>>           normal send() */
>>      printf ("error\n");
>>     else
>>      printf (".");
>> }
>> return 0;
>>
>>
>> }
>> And This is the ethereal's response :
>>
>> No.     Time        Source                Destination           Protocol
>> Info
>>        1 0.000000    192.168.0.140         192.168.0.146         TCP   0
>>  > 0 [] Seq=0 Ack=0 Win=0, bogus TCP header length (0, must be at least
>>  > 20)
>>
>> Frame 1 (60 bytes on wire, 60 bytes captured) Ethernet II, Src:
>> 3com_b6:d6:29 (00:50:da:b6:d6:29), Dst: DellComp_d5:be:c6
>> (00:b0:d0:d5:be:c6) Internet Protocol, Src: 192.168.0.140 (192.168.0.140),
>> Dst: 192.168.0.146 (192.168.0.146)
>>      Version: 4
>>      Header length: 20 bytes
>>      Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00)
>>      Total Length: 40
>>      Identification: 0x0000 (0)
>>      Flags: 0x04 (Don't Fragment)
>>      Fragment offset: 0
>>      Time to live: 255
>>      Protocol: TCP (0x06)
>>      Header checksum: 0xf960 [correct]
>>      Source: 192.168.0.140 (192.168.0.140) Destination: 192.168.0.146
>>      (192.168.0.146)
>> Transmission Control Protocol, Src Port: 0 (0), Dst Port: 0 (0), Seq: 0
>>      Source port: 0 (0)
>>      Destination port: 0 (0)
>>      Sequence number: 0    (relative sequence number) Header length: 0
>>      bytes (bogus, must be at least 20)
>