snoop_dhcp.c revision 2e3b64671f0fdac42d7fb21a8fa7e3ce9fce3359
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/sysmacros.h>
#include <netinet/in.h>
#include <netinet/dhcp.h>
#include <arpa/inet.h>
#include <dhcp_inittab.h>
#include <dhcp_symbol.h>
#include "snoop.h"
extern char *dlc_header;
static char *show_htype(int);
static const char *show_msgtype(unsigned char);
static int show_options(unsigned char *, int);
static void display_ip(int, char *, char *, unsigned char **);
static void display_ascii(char *, char *, unsigned char **);
static void display_number(char *, char *, unsigned char **);
static void display_ascii_hex(char *, unsigned char **);
static unsigned char bootmagic[] = BOOTMAGIC; /* rfc 1048 */
static char *option_types[] = {
"", /* 0 */
"Subnet Mask", /* 1 */
"UTC Time Offset", /* 2 */
"Router", /* 3 */
"RFC868 Time Servers", /* 4 */
"IEN 116 Name Servers", /* 5 */
"DNS Servers", /* 6 */
"UDP LOG Servers", /* 7 */
"RFC 865 Cookie Servers", /* 8 */
"RFC 1179 Line Printer Servers (LPR)", /* 9 */
"Impress Servers", /* 10 */
"RFC 887 Resource Location Servers", /* 11 */
"Client Hostname", /* 12 */
"Boot File size in 512 byte Blocks", /* 13 */
"Merit Dump File", /* 14 */
"DNS Domain Name", /* 15 */
"SWAP Server", /* 16 */
"Client Root Path", /* 17 */
"BOOTP options extensions path", /* 18 */
"IP Forwarding Flag", /* 19 */
"NonLocal Source Routing Flag", /* 20 */
"Policy Filters for NonLocal Routing", /* 21 */
"Maximum Datagram Reassembly Size", /* 22 */
"Default IP Time To Live", /* 23 */
"Path MTU Aging Timeout", /* 24 */
"Path MTU Size Plateau Table", /* 25 */
"Interface MTU Size", /* 26 */
"All Subnets are Local Flag", /* 27 */
"Broadcast Address", /* 28 */
"Perform Mask Discovery Flag", /* 29 */
"Mask Supplier Flag", /* 30 */
"Perform Router Discovery Flag", /* 31 */
"Router Solicitation Address", /* 32 */
"Static Routes", /* 33 */
"Trailer Encapsulation Flag", /* 34 */
"ARP Cache Timeout Seconds", /* 35 */
"Ethernet Encapsulation Flag", /* 36 */
"TCP Default Time To Live", /* 37 */
"TCP Keepalive Interval Seconds", /* 38 */
"TCP Keepalive Garbage Flag", /* 39 */
"NIS Domainname", /* 40 */
"NIS Servers", /* 41 */
"Network Time Protocol Servers", /* 42 */
"Vendor Specific Options", /* 43 */
"NetBIOS RFC 1001/1002 Name Servers", /* 44 */
"NetBIOS Datagram Dist. Servers", /* 45 */
"NetBIOS Node Type", /* 46 */
"NetBIOS Scope", /* 47 */
"X Window Font Servers", /* 48 */
"X Window Display Manager Servers", /* 49 */
"Requested IP Address", /* 50 */
"IP Address Lease Time", /* 51 */
"Option Field Overload Flag", /* 52 */
"DHCP Message Type", /* 53 */
"DHCP Server Identifier", /* 54 */
"Option Request List", /* 55 */
"Error Message", /* 56 */
"Maximum DHCP Message Size", /* 57 */
"Renewal (T1) Time Value", /* 58 */
"Rebinding (T2) Time Value", /* 59 */
"Client Class Identifier =", /* 60 */
"Client Identifier =", /* 61 */
"Netware IP Domain =", /* 62 */
"Netware IP Options =", /* 63 */
"NISPLUS Domainname", /* 64 */
"NISPLUS Servers", /* 65 */
"TFTP Server Name", /* 66 */
"Option BootFile Name", /* 67 */
"Mobile IP Agents", /* 68 */
"Simple Mail (SMTP) Servers", /* 69 */
"Post Office (POP3) Servers", /* 70 */
"Net News (NNTP) Servers", /* 71 */
"WorldWideWeb Servers", /* 72 */
"Finger Servers", /* 73 */
"Internet Relay Chat (IRC) Servers", /* 74 */
"StreetTalk Servers", /* 75 */
"StreetTalk Directory Assist. Servers", /* 76 */
"User Class Identifier", /* 77 */
};
#define OPTIONS_ARRAY_SIZE 78
int
interpret_dhcp(int flags, PKT *dp, int len)
{
if (flags & F_SUM) {
if ((memcmp(dp->cookie, bootmagic, sizeof (bootmagic)) == 0) &&
(len >= BASE_PKT_SIZE + 3) &&
dp->options[0] == CD_DHCP_TYPE) {
(void) sprintf(get_sum_line(),
"DHCP/BOOTP %s", show_msgtype(dp->options[2]));
} else {
switch (ntohs(dp->op)) {
case BOOTREQUEST:
(void) sprintf(get_sum_line(),
"DHCP/BOOTP BOOTREQUEST");
break;
case BOOTREPLY:
(void) sprintf(get_sum_line(),
"DHCP/BOOTP BOOTREPLY");
break;
}
}
}
if (flags & F_DTAIL) {
show_header("DHCP: ", "Dynamic Host Configuration Protocol",
len);
show_space();
(void) sprintf(get_line((char *)(uintptr_t)dp->htype -
dlc_header, 1),
"Hardware address type (htype) = %d (%s)", dp->htype,
show_htype(dp->htype));
(void) sprintf(get_line((char *)(uintptr_t)dp->hlen -
dlc_header, 1),
"Hardware address length (hlen) = %d octets", dp->hlen);
(void) sprintf(get_line((char *)(uintptr_t)dp->hops -
dlc_header, 1),
"Relay agent hops = %d", dp->hops);
(void) sprintf(get_line((char *)(uintptr_t)dp->xid -
dlc_header, 4),
"Transaction ID = 0x%x", ntohl(dp->xid));
(void) sprintf(get_line((char *)(uintptr_t)dp->secs -
dlc_header, 2),
"Time since boot = %d seconds", ntohs(dp->secs));
(void) sprintf(get_line((char *)(uintptr_t)dp->flags -
dlc_header, 2),
"Flags = 0x%.4x", ntohs(dp->flags));
(void) sprintf(get_line((char *)&dp->ciaddr - dlc_header, 4),
"Client address (ciaddr) = %s", inet_ntoa(dp->ciaddr));
(void) sprintf(get_line((char *)&dp->yiaddr - dlc_header, 4),
"Your client address (yiaddr) = %s",
inet_ntoa(dp->yiaddr));
(void) sprintf(get_line((char *)&dp->siaddr - dlc_header, 4),
"Next server address (siaddr) = %s",
inet_ntoa(dp->siaddr));
(void) sprintf(get_line((char *)&dp->giaddr - dlc_header, 4),
"Relay agent address (giaddr) = %s",
inet_ntoa(dp->giaddr));
if (dp->htype == 1) {
(void) sprintf(get_line((char *)dp->chaddr -
dlc_header, dp->hlen),
"Client hardware address (chaddr) = %.2X:%.2X:%.2X:%.2X:%.2X:%.2X",
dp->chaddr[0],
dp->chaddr[1],
dp->chaddr[2],
dp->chaddr[3],
dp->chaddr[4],
dp->chaddr[5]);
}
/*
* Check cookie, process options
*/
if (memcmp(dp->cookie, bootmagic, sizeof (bootmagic)) != 0) {
(void) sprintf(get_line(0, 0),
"Unrecognized cookie: 0x%.2X%.2X%.2X%.2X\n",
dp->cookie[0],
dp->cookie[1],
dp->cookie[2],
dp->cookie[3]);
return (0);
}
show_space();
show_header("DHCP: ", "(Options) field options", len);
show_space();
switch (show_options(dp->options, (len - BASE_PKT_SIZE))) {
case 0:
/* No option overloading */
if (*(unsigned char *)(dp->sname) != '\0') {
(void) sprintf(get_line(0, 0),
"Server Name = %s", dp->sname);
}
if (*(unsigned char *)(dp->file) != '\0') {
(void) sprintf(get_line(0, 0),
"Boot File Name = %s", dp->file);
}
break;
case 1:
/* file field used */
if (*(unsigned char *)(dp->sname) != '\0') {
(void) sprintf(get_line(0, 0),
"Server Name = %s", dp->sname);
}
show_space();
show_header("DHCP: ", "(File) field options", len);
show_space();
(void) show_options(dp->file, 128);
break;
case 2:
/* sname field used for options */
if (*(unsigned char *)(dp->file) != '\0') {
(void) sprintf(get_line(0, 0),
"Boot File Name = %s", dp->file);
}
show_space();
show_header("DHCP: ", "(Sname) field options", len);
show_space();
(void) show_options(dp->sname, 64);
break;
case 3:
show_space();
show_header("DHCP: ", "(File) field options", len);
show_space();
(void) show_options(dp->file, 128);
show_space();
show_header("DHCP: ", "(Sname) field options", len);
show_space();
(void) show_options(dp->sname, 64);
break;
};
}
return (len);
}
static int
show_options(unsigned char *cp, int len)
{
char *prmpt;
unsigned char *end, *vend;
unsigned char *start, save;
int items, i;
int nooverload = 0;
ushort_t s_buf;
struct in_addr tmp;
char scratch[128];
dhcp_symbol_t *entry;
char *decoded_opt;
int opt_len;
start = cp;
end = (unsigned char *)cp + len;
while (start < end) {
if (*start == CD_PAD) {
start++;
continue;
}
if (*start == CD_END)
break; /* done */
save = *start++;
switch (save) {
/* Network order IP address(es) */
case CD_SUBNETMASK:
case CD_ROUTER_SOLICIT_SERV:
case CD_BROADCASTADDR:
case CD_REQUESTED_IP_ADDR:
case CD_SERVER_ID:
/* Single IP address */
if (*start != 4) {
(void) sprintf(get_line(0, 0),
"Error: Bad %s", option_types[save]);
} else {
start++;
display_ip(1, "%s = %s", option_types[save],
&start);
}
break;
case CD_ROUTER:
case CD_TIMESERV:
case CD_IEN116_NAME_SERV:
case CD_DNSSERV:
case CD_LOG_SERV:
case CD_COOKIE_SERV:
case CD_LPR_SERV:
case CD_IMPRESS_SERV:
case CD_RESOURCE_SERV:
case CD_SWAP_SERV:
case CD_NIS_SERV:
case CD_NTP_SERV:
case CD_NETBIOS_NAME_SERV:
case CD_NETBIOS_DIST_SERV:
case CD_XWIN_FONT_SERV:
case CD_XWIN_DISP_SERV:
case CD_NISPLUS_SERVS:
case CD_MOBILE_IP_AGENT:
case CD_SMTP_SERVS:
case CD_POP3_SERVS:
case CD_NNTP_SERVS:
case CD_WWW_SERVS:
case CD_FINGER_SERVS:
case CD_IRC_SERVS:
case CD_STREETTALK_SERVS:
case CD_STREETTALK_DA_SERVS:
/* Multiple IP addresses */
if ((*start % 4) != 0) {
(void) sprintf(get_line(0, 0),
"Error: Bad %s address",
option_types[save]);
} else {
*start++;
display_ip((*start / 4), "%s at = %s",
option_types[save], &start);
}
break;
case CD_TFTP_SERV_NAME:
case CD_HOSTNAME:
case CD_DUMP_FILE:
case CD_DNSDOMAIN:
case CD_ROOT_PATH:
case CD_NIS_DOMAIN:
case CD_NETBIOS_SCOPE:
case CD_MESSAGE:
case CD_NISPLUS_DMAIN:
case CD_OPT_BOOTFILE_NAME:
case CD_USER_CLASS_ID:
/* Ascii strings */
display_ascii("%s = %s", option_types[save], &start);
break;
case CD_TIMEOFFSET:
case CD_IPTTL:
case CD_PATH_MTU_TIMEOUT:
case CD_ARP_TIMEOUT:
case CD_TCP_TTL:
case CD_TCP_KALIVE_INTVL:
case CD_T1_TIME:
case CD_T2_TIME:
case CD_LEASE_TIME:
/* Number: seconds */
display_number("%s = %d seconds", option_types[save],
&start);
break;
case CD_IP_FORWARDING_ON:
case CD_NON_LCL_ROUTE_ON:
case CD_ALL_SUBNETS_LCL_ON:
case CD_MASK_DISCVRY_ON:
case CD_MASK_SUPPLIER_ON:
case CD_ROUTER_DISCVRY_ON:
case CD_TRAILER_ENCAPS_ON:
case CD_ETHERNET_ENCAPS_ON:
case CD_TCP_KALIVE_GRBG_ON:
/* Number: hex flag */
display_number("%s flag = 0x%x", option_types[save],
&start);
break;
case CD_MAXIPSIZE:
case CD_MTU:
case CD_MAX_DHCP_SIZE:
/* Number: bytes */
display_number("%s = %d bytes", option_types[save],
&start);
break;
case CD_CLASS_ID:
case CD_CLIENT_ID:
case CD_NW_IP_DOMAIN:
case CD_NW_IP_OPTIONS:
/* Hex ascii strings */
display_ascii_hex(option_types[save], &start);
break;
case CD_BOOT_SIZE:
display_number("%s = %d 512 byte blocks",
"Boot file size", &start);
break;
case CD_POLICY_FILTER:
if ((*start % 8) != 0) {
(void) sprintf(get_line(0, 0),
"Error: Bad Policy Filter option");
} else {
items = *start++ / 8;
for (i = 0; i < items; i++) {
display_ip(1,
"%s = %s",
"Policy Destination",
&start);
display_ip(1, "%s = %s", "Mask",
&start);
}
}
break;
case CD_PATH_MTU_TABLE_SZ:
if (*start % 2 != 0) {
(void) sprintf(get_line(0, 0),
"Error: Bad Path MTU Table");
} else {
(void) sprintf(get_line(0, 0),
"\tPath MTU Plateau Table:");
(void) sprintf(get_line(0, 0),
"\t=======================");
items = *start / sizeof (ushort_t);
++start;
for (i = 0; i < items; i++) {
if (IS_P2ALIGNED(start,
sizeof (ushort_t))) {
/* LINTED: improper alignment */
s_buf = *(ushort_t *)start;
} else {
memcpy((char *)&s_buf,
start, sizeof (short));
}
(void) sprintf(get_line(0, 0),
"\t\tEntry %d:\t\t%d", i,
ntohs(s_buf));
start += sizeof (ushort_t);
}
}
break;
case CD_STATIC_ROUTE:
if ((*start % 8) != 0) {
(void) sprintf(get_line(0, 0),
"Error: Bad Static Route option: %d",
*start);
} else {
items = *start++ / 8;
for (i = 0; i < items; i++) {
memcpy((char *)&tmp, start,
sizeof (struct in_addr));
(void) strcpy(scratch, inet_ntoa(tmp));
start += sizeof (ulong_t);
memcpy((char *)&tmp, start,
sizeof (struct in_addr));
(void) sprintf(get_line(0, 0),
"Static route from %s to %s",
scratch, inet_ntoa(tmp));
start += sizeof (ulong_t);
}
}
break;
case CD_VENDOR_SPEC:
i = *start++;
(void) sprintf(get_line(0, 0),
"Vendor-specific Options (%d total octets):", i);
/*
* We don't know what these things are, so just
* display the option number, length, and value
* (hex).
*/
vend = (uchar_t *)((uchar_t *)start + i);
while (start < vend && *start != CD_END) {
if (*start == CD_PAD) {
start++;
continue;
}
(void) sprintf(scratch,
"\t(%.2d) %.2d octets", *start,
*(uchar_t *)((uchar_t *)start + 1));
start++;
display_ascii_hex(scratch, &start);
}
start = vend; /* in case CD_END found */
break;
case CD_NETBIOS_NODE_TYPE:
if (*start != 1) {
(void) sprintf(get_line(0, 0),
"Error: Bad '%s' parameter",
option_types[CD_NETBIOS_NODE_TYPE]);
} else {
char *type;
start++;
switch (*start) {
case 0x1:
type = "Broadcast Node";
break;
case 0x2:
type = "Point To Point Node";
break;
case 0x4:
type = "Mixed Mode Node";
break;
case 0x8:
type = "Hybrid Node";
break;
default:
type = "??? Node";
break;
};
(void) sprintf(get_line(0, 0),
"%s = %s (%d)",
option_types[CD_NETBIOS_NODE_TYPE],
type, *start);
start++;
}
break;
case CD_OPTION_OVERLOAD:
if (*start != 1) {
(void) sprintf(get_line(0, 0),
"Bad Option Overload value.");
} else {
start++;
nooverload = *start++;
}
break;
case CD_DHCP_TYPE:
if (*start < 1 || *start > 7) {
(void) sprintf(get_line(0, 0),
"Bad DHCP Message Type.");
} else {
start++;
(void) sprintf(get_line(0, 0),
"Message type = %s",
show_msgtype(*start));
start++;
}
break;
case CD_REQUEST_LIST:
opt_len = *start++;
(void) sprintf(get_line(0, 0),
"Requested Options:");
for (i = 0; i < opt_len; i++) {
entry = NULL;
if (*start < OPTIONS_ARRAY_SIZE) {
prmpt = option_types[*start];
} else {
entry = inittab_getbycode(
ITAB_CAT_STANDARD|ITAB_CAT_SITE,
ITAB_CONS_SNOOP, *start);
if (entry == NULL) {
if (*start >= DHCP_SITE_OPT &&
*start <= DHCP_END_SITE) {
prmpt = "Site Option";
} else {
prmpt = "Unrecognized "
"Option";
}
} else {
prmpt = entry->ds_name;
}
}
(void) sprintf(get_line(0, 0),
"\t%2d (%s)", *start, prmpt);
start++;
free(entry);
}
break;
default:
opt_len = *start++;
entry = inittab_getbycode(
ITAB_CAT_STANDARD|ITAB_CAT_SITE,
ITAB_CONS_SNOOP, save);
if (entry == NULL) {
if (save >= DHCP_SITE_OPT &&
save <= DHCP_END_SITE)
prmpt = "Site";
else
prmpt = "Unrecognized";
decoded_opt = NULL;
} else {
if (save < OPTIONS_ARRAY_SIZE) {
prmpt = option_types[save];
} else {
prmpt = entry->ds_name;
}
decoded_opt = inittab_decode(entry, start,
opt_len, B_TRUE);
}
if (decoded_opt == NULL) {
(void) sprintf(get_line(0, 0),
"%s Option = %d, length = %d octets",
prmpt, save, opt_len);
start--;
display_ascii_hex("\tValue =", &start);
} else {
(void) sprintf(get_line(0, 0), "%s = %s", prmpt,
decoded_opt);
start += opt_len;
free(decoded_opt);
}
free(entry);
break;
};
}
return (nooverload);
}
static char *
show_htype(int t)
{
switch (t) {
case 1:
return ("Ethernet (10Mb)");
case 2:
return ("Experimental Ethernet (3MB)");
case 3:
return ("Amateur Radio AX.25");
case 4:
return ("Proteon ProNET Token Ring");
case 5:
return ("Chaos");
case 6:
return ("IEEE 802");
case 7:
return ("ARCNET");
case 8:
return ("Hyperchannel");
case 9:
return ("Lanstar");
case 10:
return ("Autonet");
case 11:
return ("LocalTalk");
case 12:
return ("LocalNet");
case 13:
return ("Ultra Link");
case 14:
return ("SMDS");
case 15:
return ("Frame Relay");
case 16:
return ("ATM");
case ARPHRD_IB:
return ("IPIB");
};
return ("UNKNOWN");
}
static const char *
show_msgtype(unsigned char type)
{
/*
* note: the ordering here allows direct indexing of the table
* based on the RFC2131 packet type value passed in.
*/
static const char *types[] = {
"BOOTP",
"DHCPDISCOVER", "DHCPOFFER", "DHCPREQUEST", "DHCPDECLINE",
"DHCPACK", "DHCPNAK", "DHCPRELEASE", "DHCPINFORM"
};
if (type > (sizeof (types) / sizeof (*types)) || types[type] == NULL)
return ("UNKNOWN");
return (types[type]);
}
static void
display_ip(int items, char *fmt, char *msg, unsigned char **opt)
{
struct in_addr tmp;
int i;
for (i = 0; i < items; i++) {
memcpy((char *)&tmp, *opt, sizeof (struct in_addr));
(void) sprintf(get_line(0, 0), fmt, msg, inet_ntoa(tmp));
*opt += 4;
}
}
static void
display_ascii(char *fmt, char *msg, unsigned char **opt)
{
static unsigned char buf[256];
int len = **opt;
unsigned char slen = len;
if (len >= sizeof (buf))
len = sizeof (buf) - 1;
(*opt)++;
memcpy(buf, *opt, len);
*(unsigned char *)(buf + len) = '\0';
(void) sprintf(get_line(0, 0), fmt, msg, buf);
(*opt) += slen;
}
static void
display_number(char *fmt, char *msg, unsigned char **opt)
{
int len = **opt;
unsigned long l_buf = 0;
unsigned short s_buf = 0;
if (len > 4) {
(*opt)++;
(void) sprintf(get_line(0, 0), fmt, msg, 0xdeadbeef);
return;
}
switch (len) {
case sizeof (uchar_t):
(*opt)++;
(void) sprintf(get_line(0, 0), fmt, msg, **opt);
break;
case sizeof (ushort_t):
(*opt)++;
if (IS_P2ALIGNED(*opt, sizeof (ushort_t)))
/* LINTED: improper alignment */
s_buf = *(unsigned short *)*opt;
else
memcpy((char *)&s_buf, *opt, len);
(void) sprintf(get_line(0, 0), fmt, msg, ntohs(s_buf));
break;
case sizeof (ulong_t):
(*opt)++;
if (IS_P2ALIGNED(*opt, sizeof (ulong_t)))
/* LINTED: improper alignment */
l_buf = *(unsigned long *)*opt;
else
memcpy((char *)&l_buf, *opt, len);
(void) sprintf(get_line(0, 0), fmt, msg, ntohl(l_buf));
break;
}
(*opt) += len;
}
static void
display_ascii_hex(char *msg, unsigned char **opt)
{
int printable;
char buffer[512];
char *line, *tmp, *ap, *fmt;
int i, j, len = **opt;
line = get_line(0, 0);
(*opt)++;
if (len >= 255) {
(void) sprintf(line, "\t%s <TOO LONG>", msg);
return;
}
for (printable = 1, tmp = (char *)(*opt), ap = buffer;
tmp < (char *)&((*opt)[len]); tmp++) {
if (isprint(*tmp))
*ap++ = *tmp;
else {
*ap++ = '.';
printable = 0;
}
}
*ap = '\0';
if (!printable) {
for (tmp = (char *)(*opt), ap = buffer;
(tmp < (char *)&((*opt)[len])) && (ap < &buffer[512]);
tmp++) {
ap += sprintf(ap, "0x%02X ", *(uchar_t *)(tmp));
}
*(--ap) = '\0';
i = ap - buffer;
fmt = "%s\t%s (unprintable)";
} else {
i = strlen(buffer);
fmt = "%s\t\"%s\"";
}
(*opt) += len;
j = strlen(msg) + (MAXLINE / 2) - 30;
if (i > j) {
buffer[j - 1] = '.';
buffer[j - 2] = '.';
buffer[j - 3] = '.';
buffer[j] = '\0';
}
(void) sprintf(line, fmt, msg, buffer);
}