/* * netsniff-ng - the packet sniffing beast * Copyright 2009, 2010 Daniel Borkmann. * Subject to the GPL, version 2. */ #include #include /* for ntohs() */ #include "proto.h" #include "protos.h" #include "lookup.h" #include "pkt_buff.h" #include "built_in.h" struct arphdr { uint16_t ar_hrd; /* format of hardware address */ uint16_t ar_pro; /* format of protocol address */ uint8_t ar_hln; /* length of hardware address */ uint8_t ar_pln; /* length of protocol address */ uint16_t ar_op; /* ARP opcode (command) */ uint8_t ar_sha[6]; /* sender hardware address */ uint8_t ar_sip[4]; /* sender IP address */ uint8_t ar_tha[6]; /* target hardware address */ uint8_t ar_tip[4]; /* target IP address */ } __packed; #define ARPHRD_ETHER 1 #define ARPHRD_IEEE802 6 #define ARPHRD_ARCNET 7 #define ARPHRD_ATM 16 #define ARPHRD_ATM2 19 #define ARPHRD_SERIAL 20 #define ARPHRD_ATM3 21 #define ARPHRD_IEEE1394 24 #define ARPOP_REQUEST 1 /* ARP request */ #define ARPOP_REPLY 2 /* ARP reply */ #define ARPOP_RREQUEST 3 /* RARP request */ #define ARPOP_RREPLY 4 /* RARP reply */ #define ARPOP_InREQUEST 8 /* InARP request */ #define ARPOP_InREPLY 9 /* InARP reply */ #define ARPOP_NAK 10 /* (ATM)ARP NAK */ static void arp(struct pkt_buff *pkt) { char *hrd; char *pro; char *opcode; struct arphdr *arp = (struct arphdr *) pkt_pull(pkt, sizeof(*arp)); if (arp == NULL) return; switch (ntohs(arp->ar_hrd)) { case ARPHRD_ETHER: hrd = "Ethernet"; break; case ARPHRD_IEEE802: hrd = "IEEE 802"; break; case ARPHRD_ARCNET: hrd = "ARCNET"; break; case ARPHRD_ATM: case ARPHRD_ATM2: case ARPHRD_ATM3: hrd = "ATM"; break; case ARPHRD_SERIAL: hrd = "Serial Line"; break; case ARPHRD_IEEE1394: hrd = "IEEE 1394.1995"; break; default: hrd = "Unknown"; break; } pro = lookup_ether_type(ntohs(arp->ar_pro)); if (pro == NULL) pro = "Unknown"; switch (ntohs(arp->ar_op)) { case ARPOP_REQUEST: opcode = "ARP request"; break; case ARPOP_REPLY: opcode = "ARP reply"; break; case ARPOP_RREQUEST: opcode = "RARP request"; break; case ARPOP_RREPLY: opcode = "RARP reply"; break; case ARPOP_InREQUEST: opcode = "InARP request"; break; case ARPOP_InREPLY: opcode = "InARP reply"; break; case ARPOP_NAK: opcode = "(ATM) ARP NAK"; break; default: opcode = "Unknown"; break; }; tprintf(" [ ARP "); tprintf("Format HA (%u => %s), ", ntohs(arp->ar_hrd), hrd); tprintf("Format Proto (0x%.4x => %s), ", ntohs(arp->ar_pro), pro); tprintf("HA Len (%u), ", arp->ar_hln); tprintf("Proto Len (%u), ", arp->ar_pln); tprintf("Opcode (%u => %s)", ntohs(arp->ar_op), opcode); tprintf(" ]\n"); } static void arp_less(struct pkt_buff *pkt) { char *opcode = NULL; struct arphdr *arp = (struct arphdr *) pkt_pull(pkt, sizeof(*arp)); if (arp == NULL) return; switch (ntohs(arp->ar_op)) { case ARPOP_REQUEST: opcode = "ARP request"; break; case ARPOP_REPLY: opcode = "ARP reply"; break; case ARPOP_RREQUEST: opcode = "RARP request"; break; case ARPOP_RREPLY: opcode = "RARP reply"; break; case ARPOP_InREQUEST: opcode = "InARP request"; break; case ARPOP_InREPLY: opcode = "InARP reply"; break; case ARPOP_NAK: opcode = "(ATM) ARP NAK"; break; default: opcode = "Unknown"; break; }; tprintf(" Op %s", opcode); } struct protocol arp_ops = { .key = 0x0806, .print_full = arp, .print_less = arp_less, }; /option>