2 * Routines for ARP packet disassembly
4 * $Id: packet-arp.c,v 1.6 1998/10/13 05:20:53 guy Exp $
6 * Ethereal - Network traffic analyzer
7 * By Gerald Combs <gerald@zing.org>
8 * Copyright 1998 Gerald Combs
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version 2
14 * of the License, or (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
35 #ifdef HAVE_SYS_TYPES_H
36 # include <sys/types.h>
39 #ifdef HAVE_NETINET_IN_H
40 # include <netinet/in.h>
48 dissect_arp(const u_char *pd, int offset, frame_data *fd, GtkTree *tree) {
50 GtkWidget *arp_tree, *ti;
52 static value_string op_vals[] = { {ARPOP_REQUEST, "ARP request" },
53 {ARPOP_REPLY, "ARP reply" },
54 {ARPOP_RREQUEST, "RARP request"},
55 {ARPOP_RREPLY, "RARP reply" } };
56 #define N_OP_VALS (sizeof op_vals / sizeof op_vals[0])
58 /* To do: Check for {cap len,pkt len} < struct len */
59 ea.ar_hrd = pntohs(&pd[offset]);
60 ea.ar_pro = pntohs(&pd[offset + 2]);
61 ea.ar_hln = (guint8) pd[offset + 4];
62 ea.ar_pln = (guint8) pd[offset + 5];
63 ea.ar_op = pntohs(&pd[offset + 6]);
64 memcpy(&ea.arp_sha, &pd[offset + 8], 6);
65 memcpy(&ea.arp_spa, &pd[offset + 14], 4);
66 memcpy(&ea.arp_tha, &pd[offset + 18], 6);
67 memcpy(&ea.arp_tpa, &pd[offset + 24], 4);
69 if (fd->win_info[COL_NUM]) { strcpy(fd->win_info[COL_PROTOCOL], "ARP"); }
72 if ((op_str = match_strval(ea.ar_op, op_vals, N_OP_VALS)))
73 ti = add_item_to_tree(GTK_WIDGET(tree), offset, 28, op_str);
75 ti = add_item_to_tree(GTK_WIDGET(tree), offset, 28,
76 "Unknown ARP (opcode 0x%04x)", ea.ar_op);
77 arp_tree = gtk_tree_new();
78 add_subtree(ti, arp_tree, ETT_ARP);
79 add_item_to_tree(arp_tree, offset, 2,
80 "Hardware type: 0x%04x", ea.ar_hrd);
81 add_item_to_tree(arp_tree, offset + 2, 2,
82 "Protocol type: 0x%04x", ea.ar_pro);
83 add_item_to_tree(arp_tree, offset + 4, 1,
84 "Hardware size: 0x%02x", ea.ar_hln);
85 add_item_to_tree(arp_tree, offset + 5, 1,
86 "Protocol size: 0x%02x", ea.ar_pln);
87 add_item_to_tree(arp_tree, offset + 6, 2,
88 "Opcode: 0x%04x (%s)", ea.ar_op, op_str ? op_str : "Unknown");
89 add_item_to_tree(arp_tree, offset + 8, 6,
90 "Sender ether: %s", ether_to_str((guint8 *) ea.arp_sha));
91 add_item_to_tree(arp_tree, offset + 14, 4,
92 "Sender IP: %s", ip_to_str((guint8 *) ea.arp_spa));
93 add_item_to_tree(arp_tree, offset + 18, 6,
94 "Target ether: %s", ether_to_str((guint8 *) ea.arp_tha));
95 add_item_to_tree(arp_tree, offset + 24, 4,
96 "Target IP: %s", ip_to_str((guint8 *) ea.arp_tpa));
99 if (ea.ar_pro != ETHERTYPE_IP && fd->win_info[COL_NUM]) {
100 sprintf(fd->win_info[COL_INFO], "h/w %d (%d) prot %d (%d) op 0x%04x",
101 ea.ar_hrd, ea.ar_hln, ea.ar_pro, ea.ar_pln, ea.ar_op);
106 if (fd->win_info[COL_NUM]) {
107 sprintf(fd->win_info[COL_INFO], "Who has %s? Tell %s",
108 ip_to_str((guint8 *) ea.arp_tpa), ip_to_str((guint8 *) ea.arp_spa));
112 if (fd->win_info[COL_NUM]) {
113 sprintf(fd->win_info[COL_INFO], "%s is at %s",
114 ip_to_str((guint8 *) ea.arp_spa),
115 ether_to_str((guint8 *) ea.arp_sha));
119 if (fd->win_info[COL_NUM]) {
120 strcpy(fd->win_info[COL_PROTOCOL], "RARP");
121 sprintf(fd->win_info[COL_INFO], "Who is %s? Tell %s",
122 ether_to_str((guint8 *) ea.arp_tha),
123 ether_to_str((guint8 *) ea.arp_sha));
127 if (fd->win_info[COL_NUM]) {
128 strcpy(fd->win_info[COL_PROTOCOL], "RARP");
129 sprintf(fd->win_info[COL_INFO], "%s is at %s",
130 ether_to_str((guint8 *) ea.arp_sha),
131 ip_to_str((guint8 *) ea.arp_spa));