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/*
* netsniff-ng - the packet sniffing beast
* Copyright 2009, 2010 Daniel Borkmann.
* Subject to the GPL, version 2.
*/
#include <stdio.h>
#include <stdint.h>
#include <endian.h>
#include <netinet/in.h> /* for ntohs() */
#include <asm/byteorder.h>
#include "proto.h"
#include "dissector_eth.h"
#include "built_in.h"
#include "pkt_buff.h"
struct tcphdr {
uint16_t source;
uint16_t dest;
uint32_t seq;
uint32_t ack_seq;
#if defined(__LITTLE_ENDIAN_BITFIELD)
__extension__ uint16_t res1:4,
doff:4,
fin:1,
syn:1,
rst:1,
psh:1,
ack:1,
urg:1,
ece:1,
cwr:1;
#elif defined(__BIG_ENDIAN_BITFIELD)
__extension__ uint16_t doff:4,
res1:4,
cwr:1,
ece:1,
urg:1,
ack:1,
psh:1,
rst:1,
syn:1,
fin:1;
#else
# error "Adjust your <asm/byteorder.h> defines"
#endif
uint16_t window;
uint16_t check;
uint16_t urg_ptr;
} __packed;
static void tcp(struct pkt_buff *pkt)
{
struct tcphdr *tcp = (struct tcphdr *) pkt_pull(pkt, sizeof(*tcp));
uint16_t src, dest;
char *src_name, *dest_name;
if (tcp == NULL)
return;
src = ntohs(tcp->source);
dest = ntohs(tcp->dest);
src_name = lookup_port_tcp(src);
dest_name = lookup_port_tcp(dest);
tprintf(" [ TCP ");
tprintf("Port (%u", src);
if (src_name)
tprintf(" (%s%s%s)", colorize_start(bold), src_name,
colorize_end());
tprintf(" => %u", dest);
if (dest_name)
tprintf(" (%s%s%s)", colorize_start(bold), dest_name,
colorize_end());
tprintf("), ");
tprintf("SN (0x%x), ", ntohl(tcp->seq));
tprintf("AN (0x%x), ", ntohl(tcp->ack_seq));
tprintf("DataOff (%u), ", tcp->doff);
tprintf("Res (%u), ", tcp->res1);
tprintf("Flags (");
if (tcp->fin)
tprintf("FIN ");
if (tcp->syn)
tprintf("SYN ");
if (tcp->rst)
tprintf("RST ");
if (tcp->psh)
tprintf("PSH ");
if (tcp->ack)
tprintf("ACK ");
if (tcp->urg)
tprintf("URG ");
if (tcp->ece)
tprintf("ECE ");
if (tcp->cwr)
tprintf("CWR ");
tprintf("), ");
tprintf("Window (%u), ", ntohs(tcp->window));
tprintf("CSum (0x%.4x), ", ntohs(tcp->check));
tprintf("UrgPtr (%u)", ntohs(tcp->urg_ptr));
tprintf(" ]\n");
}
static void tcp_less(struct pkt_buff *pkt)
{
struct tcphdr *tcp = (struct tcphdr *) pkt_pull(pkt, sizeof(*tcp));
uint16_t src, dest;
char *src_name, *dest_name;
if (tcp == NULL)
return;
src = ntohs(tcp->source);
dest = ntohs(tcp->dest);
src_name = lookup_port_tcp(src);
dest_name = lookup_port_tcp(dest);
tprintf(" TCP %u", src);
if(src_name)
tprintf("(%s%s%s)", colorize_start(bold), src_name,
colorize_end());
tprintf("/%u", dest);
if(dest_name)
tprintf("(%s%s%s)", colorize_start(bold), dest_name,
colorize_end());
tprintf(" F%s",colorize_start(bold));
if (tcp->fin)
tprintf(" FIN");
if (tcp->syn)
tprintf(" SYN");
if (tcp->rst)
tprintf(" RST");
if (tcp->psh)
tprintf(" PSH");
if (tcp->ack)
tprintf(" ACK");
if (tcp->urg)
tprintf(" URG");
if (tcp->ece)
tprintf(" ECE");
if (tcp->cwr)
tprintf(" CWR");
tprintf("%s Win %u S/A 0x%x/0x%x", colorize_end(),
ntohs(tcp->window), ntohl(tcp->seq), ntohl(tcp->ack_seq));
}
struct protocol tcp_ops = {
.key = 0x06,
.print_full = tcp,
.print_less = tcp_less,
};
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