osmith
/
wireshark
forked from osmocom/wireshark
1
0
Fork 0
Code Pull Requests Releases Wiki Activity
wireshark/packet-bootp.c

534 lines
16 KiB
C
Raw Blame History

/* packet-bootp.c
* Routines for BOOTP/DHCP packet disassembly
* Gilbert Ramirez <gram@verdict.uthscsa.edu>
*
* $Id: packet-bootp.c,v 1.16 1999/03/23 03:14:35 gram Exp $
*
* The information used comes from:
* RFC 2132: DHCP Options and BOOTP Vendor Extensions
* RFC 1542: Clarifications and Extensions for the Bootstrap Protocol
* RFC 2131: Dynamic Host Configuration Protocol
*
* Ethereal - Network traffic analyzer
* By Gerald Combs <gerald@unicom.net>
* Copyright 1998 Gerald Combs
*
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#ifdef HAVE_SYS_TYPES_H
# include <sys/types.h>
#endif
#include <glib.h>
#include "packet.h"
enum field_type { none, ipv4, string, toggle, yes_no, special, opaque,
time_in_secs,
val_u_byte, val_u_short, val_u_long,
val_s_long };
struct opt_info {
char *text;
enum field_type ftype;
};
#define NUM_OPT_INFOS 77
/* returns the number of bytes consumed by this option */
static int
bootp_option(const u_char *pd, proto_tree *bp_tree, int voff, int eoff)
{
char *text;
enum field_type ftype;
u_char code = pd[voff];
int vlen = pd[voff+1];
u_char byte;
int i, consumed = vlen + 2;
u_long time_secs;
proto_tree *v_tree;
proto_item *vti;
static const char *opt53_text[] = {
"Unknown Message Type",
"Discover",
"Offer",
"Request",
"Decline",
"ACK",
"NAK",
"Release",
"Inform"
};
static const value_string nbnt_vals[] = {
{0x1, "B-node" },
{0x2, "P-node" },
{0x4, "M-node" },
{0x8, "H-node" },
{0, NULL } };
static struct opt_info opt[] = {
/* 0 */ { "Padding", none },
/* 1 */ { "Subnet Mask", ipv4 },
/* 2 */ { "Time Offset", val_s_long },
/* 3 */ { "Router", ipv4 },
/* 4 */ { "Time Server", ipv4 },
/* 5 */ { "Name Server", ipv4 },
/* 6 */ { "Domain Name Server", ipv4 },
/* 7 */ { "Log Server", ipv4 },
/* 8 */ { "Cookie Server", ipv4 },
/* 9 */ { "LPR Server", ipv4 },
/* 10 */ { "Impress Server", ipv4 },
/* 11 */ { "Resource Location Server", ipv4 },
/* 12 */ { "Host Name", string },
/* 13 */ { "Boot File Size", val_u_short },
/* 14 */ { "Merit Dump File", string },
/* 15 */ { "Domain Name", string },
/* 16 */ { "Swap Server", ipv4 },
/* 17 */ { "Root Path", string },
/* 18 */ { "Extensions Path", string },
/* 19 */ { "IP Forwarding", toggle },
/* 20 */ { "Non-Local Source Routing", toggle },
/* 21 */ { "Policy Filter", special },
/* 22 */ { "Maximum Datagram Reassembly Size", val_u_short },
/* 23 */ { "Default IP Time-to-Live", val_u_byte },
/* 24 */ { "Path MTU Aging Timeout", time_in_secs },
/* 25 */ { "Path MTU Plateau Table", val_u_short },
/* 26 */ { "Interface MTU", val_u_short },
/* 27 */ { "All Subnets are Local", yes_no },
/* 28 */ { "Broadcast Address", ipv4 },
/* 29 */ { "Perform Mask Discovery", toggle },
/* 30 */ { "Mask Supplier", yes_no },
/* 31 */ { "Perform Router Discover", toggle },
/* 32 */ { "Router Solicitation Address", ipv4 },
/* 33 */ { "Static Route", special },
/* 34 */ { "Trailer Encapsulation", toggle },
/* 35 */ { "ARP Cache Timeout", time_in_secs },
/* 36 */ { "Ethernet Encapsulation", toggle },
/* 37 */ { "TCP Default TTL", val_u_byte },
/* 38 */ { "TCP Keepalive Interval", time_in_secs },
/* 39 */ { "TCP Keepalive Garbage", toggle },
/* 40 */ { "Network Information Service Domain", string },
/* 41 */ { "Network Information Service Servers", ipv4 },
/* 42 */ { "Network Time Protocol Servers", ipv4 },
/* 43 */ { "Vendor-Specific Information", special },
/* 44 */ { "NetBIOS over TCP/IP Name Server", ipv4 },
/* 45 */ { "NetBIOS over TCP/IP Datagram Distribution Name Server", ipv4 },
/* 46 */ { "NetBIOS over TCP/IP Node Type", special },
/* 47 */ { "NetBIOS over TCP/IP Scope", string },
/* 48 */ { "X Window System Font Server", ipv4 },
/* 49 */ { "X Window System Display Manager", ipv4 },
/* 50 */ { "Requested IP Address", ipv4 },
/* 51 */ { "IP Address Lease Time", time_in_secs },
/* 52 */ { "Option Overload", special },
/* 53 */ { "DHCP Message Type", special },
/* 54 */ { "Server Identifier", ipv4 },
/* 55 */ { "Parameter Request List", special },
/* 56 */ { "Message", string },
/* 57 */ { "Maximum DHCP Message Size", val_u_short },
/* 58 */ { "Renewal Time Value", time_in_secs },
/* 59 */ { "Rebinding Time Value", time_in_secs },
/* 60 */ { "Vendor class identifier", opaque },
/* 61 */ { "Client identifier", special },
/* 64 */ { "Network Information Service+ Domain", string },
/* 65 */ { "Network Information Service+ Servers", ipv4 },
/* 66 */ { "TFTP Server Name", string },
/* 67 */ { "Bootfile name", string },
/* 68 */ { "Mobile IP Home Agent", ipv4 },
/* 69 */ { "SMTP Server", ipv4 },
/* 70 */ { "POP3 Server", ipv4 },
/* 71 */ { "NNTP Server", ipv4 },
/* 72 */ { "Default WWW Server", ipv4 },
/* 73 */ { "Default Finger Server", ipv4 },
/* 74 */ { "Default IRC Server", ipv4 },
/* 75 */ { "StreetTalk Server", ipv4 },
/* 76 */ { "StreetTalk Directory Assistance Server", ipv4 }
};
text = opt[code].text;
/* Special cases */
switch (code) {
/* Padding */
case 0:
/* check how much padding we have */
for (i = voff + 1; i < eoff; i++ ) {
if (pd[i] != 0) {
break;
}
}
i = i - voff;
proto_tree_add_item(bp_tree, voff, i, "Padding");
consumed = i;
return consumed;
/* Policy Filter */
case 21:
/* one IP address pair */
if (vlen == 8) {
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s = %s/%s", code, text,
ip_to_str((guint8*)&pd[voff+2]),
ip_to_str((guint8*)&pd[voff+6]));
}
/* > 1 IP address pair. Let's make a sub-tree */
else {
vti = proto_tree_add_item(bp_tree, voff,
consumed, "Option %d: %s", code, text);
v_tree = proto_tree_new();
proto_item_add_subtree(vti, v_tree, ETT_BOOTP_OPTION);
for (i = voff + 2; i < voff + consumed; i += 8) {
proto_tree_add_item(v_tree, i, 8, "IP Address/Mask: %s/%s",
ip_to_str((guint8*)&pd[i]),
ip_to_str((guint8*)&pd[i+4]));
}
}
break;
/* Static Route */
case 33:
/* one IP address pair */
if (vlen == 8) {
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s = %s/%s", code, text,
ip_to_str((guint8*)&pd[voff+2]),
ip_to_str((guint8*)&pd[voff+6]));
}
/* > 1 IP address pair. Let's make a sub-tree */
else {
vti = proto_tree_add_item(bp_tree, voff,
consumed, "Option %d: %s", code, text);
v_tree = proto_tree_new();
proto_item_add_subtree(vti, v_tree, ETT_BOOTP_OPTION);
for (i = voff + 2; i < voff + consumed; i += 8) {
proto_tree_add_item(v_tree, i, 8,
"Destination IP Address/Router: %s/%s",
ip_to_str((guint8*)&pd[i]),
ip_to_str((guint8*)&pd[i+4]));
}
}
break;
/* Vendor-Specific Info */
case 43:
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s", code, text);
break;
/* NetBIOS-over-TCP/IP Node Type */
case 46:
byte = pd[voff+2];
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s = %s", code, text,
val_to_str(byte, nbnt_vals,
"Unknown (0x%02x)"));
break;
/* DHCP Message Type */
case 53:
byte = pd[voff+2];
if (byte > 0 && byte < 9) {
i = byte;
}
else {
i = 0;
}
proto_tree_add_item(bp_tree, voff, 3, "Option %d: %s = DHCP %s",
code, text, opt53_text[i]);
break;
/* Parameter Request List */
case 55:
vti = proto_tree_add_item(bp_tree, voff,
vlen + 2, "Option %d: %s", code, text);
v_tree = proto_tree_new();
proto_item_add_subtree(vti, v_tree, ETT_BOOTP_OPTION);
for (i = 0; i < vlen; i++) {
byte = pd[voff+2+i];
if (byte < NUM_OPT_INFOS) {
proto_tree_add_item(v_tree, voff+2+i, 1, "%d = %s",
byte, opt[byte].text);
}
else {
proto_tree_add_item(vti, voff+2+i, 1,
"Unknown Option Code: %d", byte);
}
}
break;
/* Client Identifier */
case 61:
/* We *MAY* use hwtype/hwaddr. If we have 7 bytes, I'll
guess that the first is the hwtype, and the last 6 are
the hw addr */
if (vlen == 7) {
vti = proto_tree_add_item(bp_tree, voff,
consumed, "Option %d: %s", code, text);
v_tree = proto_tree_new();
proto_item_add_subtree(vti, v_tree, ETT_BOOTP_OPTION);
proto_tree_add_item(v_tree, voff+2, 1,
"Hardware type: %s",
arphrdtype_to_str(pd[voff+2],
"Unknown (0x%02x)"));
proto_tree_add_item(v_tree, voff+3, 6,
"Client hardware address: %s",
arphrdaddr_to_str((guint8*)&pd[voff+3],
6, pd[voff+2]));
}
/* otherwise, it's opaque data */
else {
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s (%d bytes)", code, text, vlen);
}
break;
/* End Option */
case 255:
proto_tree_add_item(bp_tree, voff, 1, "End Option");
consumed = 1;
return consumed;
default:
/* nothing */
break;
}
/* Normal cases */
if (code < NUM_OPT_INFOS) {
text = opt[code].text;
ftype = opt[code].ftype;
switch (ftype) {
case special:
return consumed;
case ipv4:
/* one IP address */
if (vlen == 4) {
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s = %s", code, text,
ip_to_str((guint8*)&pd[voff+2]));
}
/* > 1 IP addresses. Let's make a sub-tree */
else {
vti = proto_tree_add_item(bp_tree, voff,
consumed, "Option %d: %s", code, text);
v_tree = proto_tree_new();
proto_item_add_subtree(vti, v_tree, ETT_BOOTP_OPTION);
for (i = voff + 2; i < voff + consumed; i += 4) {
proto_tree_add_item(v_tree, i, 4, "IP Address: %s",
ip_to_str((guint8*)&pd[i]));
}
}
break;
case string:
/* Fix for non null-terminated string supplied by
* John Lines <John.Lines@aeat.co.uk>
*/
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s = %.*s", code, text, vlen, &pd[voff+2]);
break;
case opaque:
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s (%d bytes)",
code, text, vlen);
break;
case val_u_short:
/* one IP address */
if (vlen == 2) {
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s = %d", code, text,
pntohs(&pd[voff+2]));
}
/* > 1 u_short */
else {
vti = proto_tree_add_item(bp_tree, voff,
consumed, "Option %d: %s", code, text);
v_tree = proto_tree_new();
proto_item_add_subtree(vti, v_tree, ETT_BOOTP_OPTION);
for (i = voff + 2; i < voff + consumed; i += 2) {
proto_tree_add_item(v_tree, i, 4, "Value: %d",
pntohs(&pd[i]));
}
}
break;
case val_u_long:
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s = %d", code, text,
pntohl(&pd[voff+2]));
break;
case val_u_byte:
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s = %d", code, text, pd[voff+2]);
break;
case toggle:
i = pd[voff+2];
if (i != 0 && i != 1) {
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s = Invalid Value %d", code, text,
pd[voff+2]);
}
else {
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s = %s", code, text,
pd[voff+2] == 0 ? "Disabled" : "Enabled");
}
break;
case yes_no:
i = pd[voff+2];
if (i != 0 && i != 1) {
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s = Invalid Value %d", code, text,
pd[voff+2]);
}
else {
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s = %s", code, text,
pd[voff+2] == 0 ? "No" : "Yes");
}
break;
case time_in_secs:
time_secs = pntohl(&pd[voff+2]);
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s = %s", code, text,
((time_secs == 0xffffffff) ?
"infinity" :
time_secs_to_str(time_secs)));
break;
default:
proto_tree_add_item(bp_tree, voff, consumed,
"Option %d: %s (%d bytes)", code, text, vlen);
}
}
else {
proto_tree_add_item(bp_tree, voff, consumed,
"Unknown Option Code: %d (%d bytes)", code, vlen);
}
return consumed;
}
void
dissect_bootp(const u_char *pd, int offset, frame_data *fd, proto_tree *tree)
{
proto_tree *bp_tree;
proto_item *ti;
int voff, eoff; /* vender offset, end offset */
if (check_col(fd, COL_PROTOCOL))
col_add_str(fd, COL_PROTOCOL, "BOOTP");
if (check_col(fd, COL_INFO)) {
if (pd[offset] == 1) {
col_add_fstr(fd, COL_INFO, "Boot Request from %s",
arphrdaddr_to_str((guint8*)&pd[offset+28],
pd[offset+2], pd[offset+1]));
}
else {
col_add_str(fd, COL_INFO, "Boot Reply");
}
}
if (tree) {
ti = proto_tree_add_item(tree, offset, END_OF_FRAME,
"Bootstrap Protocol");
bp_tree = proto_tree_new();
proto_item_add_subtree(ti, bp_tree, ETT_BOOTP);
proto_tree_add_item(bp_tree, offset, 1, pd[offset] == 1 ?
"Boot Request" : "Boot Reply");
proto_tree_add_item(bp_tree, offset + 1, 1,
"Hardware type: %s",
arphrdtype_to_str(pd[offset+1], "Unknown (0x%02x)"));
proto_tree_add_item(bp_tree, offset + 2, 1,
"Hardware address length: %d", pd[offset+2]);
proto_tree_add_item(bp_tree, offset + 3, 1,
"Hops: %d", pd[offset+3]);
proto_tree_add_item(bp_tree, offset + 4, 4,
"Transaction ID: 0x%08x", pntohl(&pd[offset+4]));
proto_tree_add_item(bp_tree, offset + 8, 2,
"Seconds elapsed: %d", pntohs(&pd[offset+8]));
proto_tree_add_item(bp_tree, offset + 10, 2,
"Broadcast flag: %d", pd[offset+10] & 1);
proto_tree_add_item(bp_tree, offset + 12, 4,
"Client IP address: %s", ip_to_str((guint8*)&pd[offset+12]));
proto_tree_add_item(bp_tree, offset + 16, 4,
"Your (client) IP address: %s", ip_to_str((guint8*)&pd[offset+16]));
proto_tree_add_item(bp_tree, offset + 20, 4,
"Next server IP address: %s", ip_to_str((guint8*)&pd[offset+20]));
proto_tree_add_item(bp_tree, offset + 24, 4,
"Relay agent IP address: %s", ip_to_str((guint8*)&pd[offset+24]));
proto_tree_add_item(bp_tree, offset + 28, pd[offset+2],
"Client hardware address: %s",
arphrdaddr_to_str((guint8*)&pd[offset+28],
pd[offset+2], pd[offset+1]));
/* The server host name is optional */
if (pd[offset+44]) {
proto_tree_add_item(bp_tree, offset + 44, 64,
"Server host name: %s", &pd[offset+44]);
}
else {
proto_tree_add_item(bp_tree, offset + 44, 64,
"Server host name not given");
}
/* Boot file */
if (pd[offset+108]) {
proto_tree_add_item(bp_tree, offset + 108, 128,
"Boot file name: %s", &pd[offset+108]);
}
else {
proto_tree_add_item(bp_tree, offset + 108, 128,
"Boot file name not given");
}
if (pntohl(&pd[offset+236]) == 0x63825363) {
proto_tree_add_item(bp_tree, offset + 236, 4,
"Magic cookie: (OK)");
}
else {
proto_tree_add_item(bp_tree, offset + 236, 4,
"Magic cookie: %s",
ip_to_str((guint8*)&pd[offset+236]));
}
voff = offset+240;
eoff = fd->cap_len;
while (voff < eoff) {
voff += bootp_option(pd, bp_tree, voff, eoff);
}
}
}
View Git Blame Copy Permalink