source: libpacketdump/eth_2048.cc @ 37dc1fb

#include <netinet/ether.h>
#include <netinet/in.h>
#include <stdio.h>
#include <inttypes.h>
#include <dlfcn.h>
#include <map>
#include "libpacketdump.h"
#include <sys/socket.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <arpa/inet.h>
#include <netdb.h>

#define DISPLAY_EXP(x,fmt,exp) \
        if ((unsigned int)len>=((char*)&ip->x-(char*)ip+sizeof(ip->x))) \
                printf(fmt,exp); \
        else \
                return; 

#define DISPLAY(x,fmt) DISPLAY_EXP(x,fmt,ip->x)

#define DISPLAYS(x,fmt) DISPLAY_EXP(x,fmt,htons(ip->x))
#define DISPLAYIP(x,fmt) DISPLAY_EXP(x,fmt,inet_ntoa(*(struct in_addr*)&ip->x))

extern "C"
void decode(int link_type,char *packet,int len)
{
        struct iphdr *ip = (struct iphdr*)packet;
        if (len>=1) {
                printf(" IP: Header Len %i",ip->ihl*4);
                printf(" Ver %i",ip->version);
        }
        DISPLAY(tos," TOS %02x")
        DISPLAYS(tot_len," Total Length %i")
        printf("\n IP:");
        DISPLAY(id," Id %i");
        DISPLAY(frag_off," Fragoff %i");
        //printf("\n IP:");
        DISPLAY(ttl," TTL %i");
        if ((unsigned int)len>=((char*)&ip->protocol-(char*)ip+sizeof(ip->protocol))) {
                struct protoent *ent=getprotobynumber(ip->protocol);
                if (ent) {
                        printf(" Proto %i (%s)",ip->protocol,ent->p_name);
                }
                else {
                        printf(" Proto %i",ip->protocol);
                }
        } else {
                printf("\n");
                return;
        }
        DISPLAYS(check," Checksum %i\n");
        DISPLAYIP(saddr," IP: Source %s ");
        DISPLAYIP(daddr,"Destination %s\n");
        decode_next(packet+sizeof(*ip),len-sizeof(*ip),"ip",ip->protocol);
        return;
}