source: libpacketdump/libpacketdump.cc @ 5c095c8

#include <libtrace.h>
#include <err.h>
#include <time.h>
#include "libpacketdump.h"
#include <stdio.h>
#include <stdlib.h>
#include <getopt.h>
#include <netinet/ether.h>
#include <netinet/in.h>
#include <stdio.h>
#include <inttypes.h>
#include <dlfcn.h>
#include <map>
#include <string>
#include <ctype.h>
#include "libpacketdump.h"

typedef void (*decode_t)(uint16_t type,char *packet,int len);

static std::map<std::string,std::map<uint16_t,decode_t> > decoders;

#define WIDTH 16

#ifndef DIRNAME
#define DIRNAME "./"
#warning "No DIRNAME set!"
#endif

void trace_dump_packet(struct libtrace_packet_t *packet)
{
        time_t sec = (time_t)trace_get_seconds(packet);
        char *link=(char *)trace_get_link(packet);

        printf("%s",ctime(&sec));
        decode_next(link,packet->size-(link-packet->buffer),"link",trace_get_link_type(packet));
}

static void generic_decode(uint16_t type,char *packet, int len) {
        int i;
        printf(" Unknown Protocol: %i",type);
        for(i=0;i<len; /* Nothing */ ) {
                int j;
                printf("\n ");
                for(j=0;j<WIDTH;j++) {
                        if (i+j<len)
                                printf(" %02x",(unsigned char)packet[i+j]);
                        else
                                printf("   ");
                }
                printf("    ");
                for(j=0;j<WIDTH;j++) {
                        if (i+j<len)
                                if (isprint((unsigned char)packet[i+j]))
                                        printf("%c",(unsigned char)packet[i+j]);
                                else
                                        printf(".");
                        else
                                printf("   ");
                }
                if (i+WIDTH>len)
                        break;
                else
                        i+=WIDTH;
        }
        printf("\n");
}

void decode_next(char *packet,int len,char *proto_name,int type)
{
        std::string sname(proto_name);
        if (decoders[sname].find(type)==decoders[sname].end()) {
                void *hdl;
                char name[1024];
                snprintf(name,sizeof(name),"%s/%s_%i.so",DIRNAME,sname.c_str(),type);
                hdl = dlopen(name,RTLD_LAZY);
                if (!hdl) 
                        decoders[sname][type]=generic_decode;
                else {
                        void *s=dlsym(hdl,"decode");
                        if (!s) {
                                decoders[sname][type]=generic_decode;
                        }
                        else
                                decoders[sname][type]=(decode_t)s;
                }
        }
        decoders[sname][type](type,packet,len);
}