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#include <stdio.h>
#include <inttypes.h>
#include <dlfcn.h>
#include "libpacketdump.h"
#include <assert.h>
#include <netdb.h>
#define SAFE(x) \
((unsigned int)len>=((char*)&tcp->x-(char*)tcp+sizeof(tcp->x)))
#define DISPLAY_EXP(x,fmt,exp) \
if (SAFE(x)) \
printf(fmt,exp); \
else \
return;
#define DISPLAY(x,fmt) DISPLAY_EXP(x,fmt,tcp->x)
#define DISPLAYS(x,fmt) DISPLAY_EXP(x,fmt,htons(tcp->x))
#define DISPLAYL(x,fmt) DISPLAY_EXP(x,fmt,htonl(tcp->x))
#define DISPLAYIP(x,fmt) DISPLAY_EXP(x,fmt,inet_ntoa(*(struct in_addr*)&tcp->x))
DLLEXPORT void decode(int link_type UNUSED,const char *packet,unsigned len)
{
unsigned char *pkt = NULL;
unsigned char type,optlen,*data;
int plen, i;
libtrace_tcp_t *tcp = (libtrace_tcp_t *)packet;
printf(" TCP:");
if (SAFE(source)) {
struct servent *ent=getservbyport(tcp->source,"tcp");
if(ent) {
printf(" Source %i (%s)",htons(tcp->source),ent->s_name);
} else {
printf(" Source %i",htons(tcp->source));
}
}
else {
printf("\n");
return;
}
if (SAFE(dest)) {
struct servent *ent=getservbyport(tcp->dest,"tcp");
if(ent) {
printf(" Dest %i (%s)",htons(tcp->dest),ent->s_name);
} else {
printf(" Dest %i",htons(tcp->dest));
}
}
else {
printf("\n");
return;
}
printf("\n TCP:");
DISPLAYL(seq," Seq %u");
printf("\n TCP:");
DISPLAYL(ack_seq," Ack %u");
if ((char*)&tcp->window-(char *)tcp>len) {
printf("\n");
return;
}
printf("\n TCP:");
printf(" DOFF %i",tcp->doff);
printf(" Flags:");
if (tcp->fin) printf(" FIN");
if (tcp->syn) printf(" SYN");
if (tcp->rst) printf(" RST");
if (tcp->psh) printf(" PSH");
if (tcp->ack) printf(" ACK");
if (tcp->urg) printf(" URG");
DISPLAYS(window," Window %i");
printf("\n TCP:");
DISPLAYS(check," Checksum %i");
DISPLAYS(urg_ptr," Urgent %i");
pkt = (unsigned char*)packet+sizeof(*tcp);
plen = (len-sizeof *tcp) < (tcp->doff*4-sizeof(*tcp))?(len-sizeof(*tcp)):(tcp->doff*4-sizeof *tcp);
while(trace_get_next_option(&pkt,&plen,&type,&optlen,&data)) {
printf("\n TCP: ");
switch(type) {
case 0:
printf("End of options");
break;
case 1:
printf("NOP");
break;
case 2:
printf("MSS %i",htons(*(uint32_t *)(data)));
break;
case 3:
printf("Winscale %i",data[0]);
break;
case 4:
printf("SACK");
break;
case 5:
printf("SACK Information");
i=0;
while(i+8<optlen) {
printf("\n TCP: %u-%u",
htonl(*(uint32_t*)&data[i]),
htonl(*(uint32_t*)&data[i+4]));
i+=8;
}
break;
case 8:
printf("Timestamp %u %u",
htonl(*(uint32_t *)&data[0]),
htonl(*(uint32_t *)&data[4])
);
break;
default:
printf("Unknown option %i",type);
}
}
printf("\n");
if (htons(tcp->source) < htons(tcp->dest))
decode_next(packet+tcp->doff*4,len-tcp->doff*4,"tcp",htons(tcp->source));
else
decode_next(packet+tcp->doff*4,len-tcp->doff*4,"tcp",htons(tcp->dest));
return;
}
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