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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 <netinet/in.h> /* for ntohs() */
#include "proto.h"
#include "protos.h"
#include "lookup.h"
#include "pkt_buff.h"
struct udphdr {
uint16_t source;
uint16_t dest;
uint16_t len;
uint16_t check;
} __packed;
static void udp(struct pkt_buff *pkt)
{
struct udphdr *udp = (struct udphdr *) pkt_pull(pkt, sizeof(*udp));
ssize_t len;
uint16_t src, dest;
char *src_name, *dest_name;
if (udp == NULL)
return;
len = ntohs(udp->len) - sizeof(*udp);
src = ntohs(udp->source);
dest = ntohs(udp->dest);
src_name = lookup_port_udp(src);
dest_name = lookup_port_udp(dest);
tprintf(" [ UDP ");
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("), ");
if(len > pkt_len(pkt) || len < 0){
tprintf("Len (%u) %s, ", ntohs(udp->len),
colorize_start_full(black, red)
"invalid" colorize_end());
}
tprintf("Len (%u Bytes, %zd Bytes Data), ", ntohs(udp->len), len);
tprintf("CSum (0x%.4x)", ntohs(udp->check));
tprintf(" ]\n");
}
static void udp_less(struct pkt_buff *pkt)
{
struct udphdr *udp = (struct udphdr *) pkt_pull(pkt, sizeof(*udp));
uint16_t src, dest;
char *src_name, *dest_name;
if (udp == NULL)
return;
src = ntohs(udp->source);
dest = ntohs(udp->dest);
src_name = lookup_port_udp(src);
dest_name = lookup_port_udp(dest);
tprintf(" UDP %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());
}
struct protocol udp_ops = {
.key = 0x11,
.print_full = udp,
.print_less = udp_less,
};
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