int AnalyzePacket(u_char *data,int size)
{
u_char *ptr;
int lest;
struct ether_header *eh;
ptr=data;
lest=size;
if(lest<sizeof(struct ether_header)){
fprintf(stderr,"lest(%d)<sizeof(struct ether_header)\n",lest);
return(-1);
}
eh=(struct ether_header *)ptr;
ptr+=sizeof(struct ether_header);
lest-=sizeof(struct ether_header);
if(ntohs(eh->ether_type)==ETHERTYPE_ARP){
fprintf(stderr,"Packet[%dbytes]\n",size);
PrintEtherHeader(eh,stdout);
AnalyzeArp(ptr,lest);
}
else if(ntohs(eh->ether_type)==ETHERTYPE_IP){
fprintf(stderr,"Packet[%dbytes]\n",size);
PrintEtherHeader(eh,stdout);
AnalyzeIp(ptr,lest);
}
else if(ntohs(eh->ether_type)==ETHERTYPE_IPV6){
fprintf(stderr,"Packet[%dbytes]\n",size);
PrintEtherHeader(eh,stdout);
AnalyzeIpv6(ptr,lest);
}
return(0);
}
int AnalyzePacket(u_char *data, int size) {
u_char *ptr = NULL;
int lest = 0;
struct ether_header *eh = NULL;
/*
struct ether_header
{
u_int8_t ether_dhost[ETH_ALEN]; // destination eth addr
u_int8_t ether_shost[ETH_ALEN]; // source ether addr
u_int16_t ether_type; // packet type ID field
} __attribute__ ((__packed__));
*/
ptr = data;
lest = size;
if (lest < sizeof(struct ether_header)) {
ExitWithTooLittleLengthError("ether_header", lest);
}
eh = (struct ether_header *) ptr;
ptr += sizeof(struct ether_header);
lest -= sizeof(struct ether_header);
if (ntohs(eh->ether_type) == ETHERTYPE_ARP) {
fprintf(stderr, "Packet[%dbytes]\n", size);
PrintEtherHeader(eh, stdout);
AnalyzeArp(ptr, lest);
}
else if (ntohs(eh->ether_type) == ETHERTYPE_IP) {
fprintf(stderr, "Packet[%dbytes]\n", size);
PrintEtherHeader(eh, stdout);
AnalyzeIp(ptr, lest);
}
else if (ntohs(eh->ether_type) == ETHERTYPE_IPV6) {
fprintf(stderr, "Packet[%dbytes]\n", size);
PrintEtherHeader(eh, stderr);
AnalyzeIpv6(ptr, lest);
}
return 0;
}