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#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <stdio.h>
#include <arpa/inet.h>
#include "libpacketdump.h"
/* Decoder for an LSA header */
DLLEXPORT void decode(int link_type UNUSED,const char *packet,unsigned len) {
libtrace_ospf_lsa_v2_t *lsa = (libtrace_ospf_lsa_v2_t *)packet;
if (len < 2)
return;
printf(" OSPF LSA: Age %u ", ntohs(lsa->age));
if (len < 3)
return;
printf("Options ");
if (lsa->lsa_options.e_bit)
printf("E ");
if (lsa->lsa_options.mc_bit)
printf("MC ");
if (lsa->lsa_options.np_bit)
printf("N/P ");
if (lsa->lsa_options.ea_bit)
printf("EA ");
if (lsa->lsa_options.dc_bit)
printf("DC ");
printf("\n");
if (len < 4)
return;
printf(" OSPF LSA: LS Type %u ", lsa->lsa_type);
switch(lsa->lsa_type) {
case 1:
printf("(Router LSA)\n");
break;
case 2:
printf("(Network LSA)\n");
break;
case 3:
printf("(Summary LSA - IP)\n");
break;
case 4:
printf("(Summary LSA - ASBR)\n");
break;
case 5:
printf("(AS External LSA)\n");
break;
default:
printf("(Unknown)\n");
}
if (len < 8)
return;
printf(" OSPF LSA: Link State ID %s ", inet_ntoa(lsa->ls_id));
if (len < 12) {
printf("\n");
return;
}
printf("Advertising Router %s\n", inet_ntoa(lsa->adv_router));
if (len < 16)
return;
printf(" OSPF LSA: Seq %u ", ntohl(lsa->seq));
if (len < 18) {
printf("\n");
return;
}
printf("Checksum %u ", ntohs(lsa->checksum));
if (len < 20) {
printf("\n");
return;
}
printf("Length %u \n", ntohs(lsa->length));
}
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