xref: /illumos-gate/usr/src/cmd/cmd-inet/usr.sbin/snoop/snoop_dhcp.c (revision 38c589b67028b0c4a9e23e712cabfdf1985e7612)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <ctype.h>
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <fcntl.h>
33 #include <string.h>
34 #include <sys/types.h>
35 #include <sys/socket.h>
36 #include <sys/sysmacros.h>
37 #include <netinet/in.h>
38 #include <netinet/dhcp.h>
39 #include <arpa/inet.h>
40 #include <dhcp_inittab.h>
41 #include <dhcp_symbol.h>
42 #include "snoop.h"
43 
44 extern char *dlc_header;
45 static char *show_htype(int);
46 static const char *show_msgtype(unsigned char);
47 static int show_options(unsigned char *, int);
48 static void display_ip(int, char *, char *, unsigned char **);
49 static void display_ascii(char *, char *, unsigned char **);
50 static void display_number(char *, char *, unsigned char **);
51 static void display_ascii_hex(char *, unsigned char **);
52 static unsigned char bootmagic[] = BOOTMAGIC;	/* rfc 1048 */
53 
54 static char *option_types[] = {
55 "",					/* 0 */
56 "Subnet Mask",				/* 1 */
57 "UTC Time Offset",			/* 2 */
58 "Router",				/* 3 */
59 "RFC868 Time Servers",			/* 4 */
60 "IEN 116 Name Servers",			/* 5 */
61 "DNS Servers",				/* 6 */
62 "UDP LOG Servers",			/* 7 */
63 "RFC 865 Cookie Servers",		/* 8 */
64 "RFC 1179 Line Printer Servers (LPR)",	/* 9 */
65 "Impress Servers",			/* 10 */
66 "RFC 887 Resource Location Servers",	/* 11 */
67 "Client Hostname",			/* 12 */
68 "Boot File size in 512 byte Blocks",	/* 13 */
69 "Merit Dump File",			/* 14 */
70 "DNS Domain Name",			/* 15 */
71 "SWAP Server",				/* 16 */
72 "Client Root Path",			/* 17 */
73 "BOOTP options extensions path",	/* 18 */
74 "IP Forwarding Flag",			/* 19 */
75 "NonLocal Source Routing Flag",		/* 20 */
76 "Policy Filters for NonLocal Routing",	/* 21 */
77 "Maximum Datagram Reassembly Size",	/* 22 */
78 "Default IP Time To Live",		/* 23 */
79 "Path MTU Aging Timeout",		/* 24 */
80 "Path MTU Size Plateau Table",		/* 25 */
81 "Interface MTU Size",			/* 26 */
82 "All Subnets are Local Flag",		/* 27 */
83 "Broadcast Address",			/* 28 */
84 "Perform Mask Discovery Flag",		/* 29 */
85 "Mask Supplier Flag",			/* 30 */
86 "Perform Router Discovery Flag",	/* 31 */
87 "Router Solicitation Address",		/* 32 */
88 "Static Routes",			/* 33 */
89 "Trailer Encapsulation Flag",		/* 34 */
90 "ARP Cache Timeout Seconds",		/* 35 */
91 "Ethernet Encapsulation Flag",		/* 36 */
92 "TCP Default Time To Live",		/* 37 */
93 "TCP Keepalive Interval Seconds",	/* 38 */
94 "TCP Keepalive Garbage Flag",		/* 39 */
95 "NIS Domainname",			/* 40 */
96 "NIS Servers",				/* 41 */
97 "Network Time Protocol Servers",	/* 42 */
98 "Vendor Specific Options",		/* 43 */
99 "NetBIOS RFC 1001/1002 Name Servers",	/* 44 */
100 "NetBIOS Datagram Dist. Servers",	/* 45 */
101 "NetBIOS Node Type",			/* 46 */
102 "NetBIOS Scope",			/* 47 */
103 "X Window Font Servers",		/* 48 */
104 "X Window Display Manager Servers",	/* 49 */
105 "Requested IP Address",			/* 50 */
106 "IP Address Lease Time",		/* 51 */
107 "Option Field Overload Flag",		/* 52 */
108 "DHCP Message Type",			/* 53 */
109 "DHCP Server Identifier",		/* 54 */
110 "Option Request List",			/* 55 */
111 "Error Message",			/* 56 */
112 "Maximum DHCP Message Size",		/* 57 */
113 "Renewal (T1) Time Value",		/* 58 */
114 "Rebinding (T2) Time Value",		/* 59 */
115 "Client Class Identifier =",		/* 60 */
116 "Client Identifier =",			/* 61 */
117 "Netware IP Domain =",			/* 62 */
118 "Netware IP Options =",			/* 63 */
119 "NISPLUS Domainname",			/* 64 */
120 "NISPLUS Servers",			/* 65 */
121 "TFTP Server Name",			/* 66 */
122 "Option BootFile Name",			/* 67 */
123 "Mobile IP Agents",			/* 68 */
124 "Simple Mail (SMTP) Servers",		/* 69 */
125 "Post Office (POP3) Servers",		/* 70 */
126 "Net News (NNTP) Servers",		/* 71 */
127 "WorldWideWeb Servers",			/* 72 */
128 "Finger Servers",			/* 73 */
129 "Internet Relay Chat (IRC) Servers",	/* 74 */
130 "StreetTalk Servers",			/* 75 */
131 "StreetTalk Directory Assist. Servers",	/* 76 */
132 "User Class Identifier",		/* 77 */
133 };
134 
135 #define	OPTIONS_ARRAY_SIZE	78
136 
137 int
138 interpret_dhcp(int flags, PKT *dp, int len)
139 {
140 	if (flags & F_SUM) {
141 		if ((memcmp(dp->cookie, bootmagic, sizeof (bootmagic)) == 0) &&
142 		    (len >= BASE_PKT_SIZE + 3) &&
143 		    dp->options[0] == CD_DHCP_TYPE) {
144 			(void) sprintf(get_sum_line(),
145 			    "DHCP/BOOTP %s", show_msgtype(dp->options[2]));
146 		} else {
147 			switch (ntohs(dp->op)) {
148 			case BOOTREQUEST:
149 				(void) sprintf(get_sum_line(),
150 				    "DHCP/BOOTP BOOTREQUEST");
151 				break;
152 			case BOOTREPLY:
153 				(void) sprintf(get_sum_line(),
154 				    "DHCP/BOOTP BOOTREPLY");
155 				break;
156 			}
157 		}
158 	}
159 	if (flags & F_DTAIL) {
160 		show_header("DHCP: ", "Dynamic Host Configuration Protocol",
161 		    len);
162 		show_space();
163 		(void) sprintf(get_line((char *)(uintptr_t)dp->htype -
164 		    dlc_header, 1),
165 		    "Hardware address type (htype) =  %d (%s)", dp->htype,
166 		    show_htype(dp->htype));
167 		(void) sprintf(get_line((char *)(uintptr_t)dp->hlen -
168 		    dlc_header, 1),
169 		    "Hardware address length (hlen) = %d octets", dp->hlen);
170 		(void) sprintf(get_line((char *)(uintptr_t)dp->hops -
171 		    dlc_header, 1),
172 		    "Relay agent hops = %d", dp->hops);
173 		(void) sprintf(get_line((char *)(uintptr_t)dp->xid -
174 		    dlc_header, 4),
175 		    "Transaction ID = 0x%x", ntohl(dp->xid));
176 		(void) sprintf(get_line((char *)(uintptr_t)dp->secs -
177 		    dlc_header, 2),
178 		    "Time since boot = %d seconds", ntohs(dp->secs));
179 		(void) sprintf(get_line((char *)(uintptr_t)dp->flags -
180 		    dlc_header, 2),
181 		    "Flags = 0x%.4x", ntohs(dp->flags));
182 		(void) sprintf(get_line((char *)&dp->ciaddr - dlc_header, 4),
183 		    "Client address (ciaddr) = %s", inet_ntoa(dp->ciaddr));
184 		(void) sprintf(get_line((char *)&dp->yiaddr - dlc_header, 4),
185 		    "Your client address (yiaddr) = %s",
186 		    inet_ntoa(dp->yiaddr));
187 		(void) sprintf(get_line((char *)&dp->siaddr - dlc_header, 4),
188 		    "Next server address (siaddr) = %s",
189 		    inet_ntoa(dp->siaddr));
190 		(void) sprintf(get_line((char *)&dp->giaddr - dlc_header, 4),
191 		    "Relay agent address (giaddr) = %s",
192 		    inet_ntoa(dp->giaddr));
193 		if (dp->htype == 1) {
194 			(void) sprintf(get_line((char *)dp->chaddr -
195 			    dlc_header, dp->hlen),
196 	"Client hardware address (chaddr) = %.2X:%.2X:%.2X:%.2X:%.2X:%.2X",
197 			    dp->chaddr[0],
198 			    dp->chaddr[1],
199 			    dp->chaddr[2],
200 			    dp->chaddr[3],
201 			    dp->chaddr[4],
202 			    dp->chaddr[5]);
203 		}
204 		/*
205 		 * Check cookie, process options
206 		 */
207 		if (memcmp(dp->cookie, bootmagic, sizeof (bootmagic)) != 0) {
208 			(void) sprintf(get_line(0, 0),
209 			    "Unrecognized cookie: 0x%.2X%.2X%.2X%.2X\n",
210 			    dp->cookie[0],
211 			    dp->cookie[1],
212 			    dp->cookie[2],
213 			    dp->cookie[3]);
214 			return (0);
215 		}
216 		show_space();
217 		show_header("DHCP: ", "(Options) field options", len);
218 		show_space();
219 		switch (show_options(dp->options, (len - BASE_PKT_SIZE))) {
220 		case 0:
221 			/* No option overloading */
222 			if (*(unsigned char *)(dp->sname) != '\0') {
223 				(void) sprintf(get_line(0, 0),
224 				    "Server Name = %s", dp->sname);
225 			}
226 			if (*(unsigned char *)(dp->file) != '\0') {
227 				(void) sprintf(get_line(0, 0),
228 				    "Boot File Name = %s", dp->file);
229 			}
230 			break;
231 		case 1:
232 			/* file field used */
233 			if (*(unsigned char *)(dp->sname) != '\0') {
234 				(void) sprintf(get_line(0, 0),
235 				    "Server Name = %s", dp->sname);
236 			}
237 			show_space();
238 			show_header("DHCP: ", "(File) field options", len);
239 			show_space();
240 			(void) show_options(dp->file, 128);
241 			break;
242 		case 2:
243 			/* sname field used for options */
244 			if (*(unsigned char *)(dp->file) != '\0') {
245 				(void) sprintf(get_line(0, 0),
246 				    "Boot File Name = %s", dp->file);
247 			}
248 			show_space();
249 			show_header("DHCP: ", "(Sname) field options", len);
250 			show_space();
251 			(void) show_options(dp->sname, 64);
252 			break;
253 		case 3:
254 			show_space();
255 			show_header("DHCP: ", "(File) field options", len);
256 			show_space();
257 			(void) show_options(dp->file, 128);
258 			show_space();
259 			show_header("DHCP: ", "(Sname) field options", len);
260 			show_space();
261 			(void) show_options(dp->sname, 64);
262 			break;
263 		};
264 	}
265 	return (len);
266 }
267 static int
268 show_options(unsigned char  *cp, int len)
269 {
270 	char *prmpt;
271 	unsigned char *end, *vend;
272 	unsigned char *start, save;
273 	int items, i;
274 	int nooverload = 0;
275 	ushort_t	s_buf;
276 	struct in_addr	tmp;
277 	char scratch[128];
278 	dhcp_symbol_t *entry;
279 	char *decoded_opt;
280 	int opt_len;
281 
282 	start = cp;
283 	end = (unsigned char *)cp + len;
284 
285 	while (start < end) {
286 		if (*start == CD_PAD) {
287 			start++;
288 			continue;
289 		}
290 		if (*start == CD_END)
291 			break;	/* done */
292 
293 		save = *start++;
294 		switch (save) {
295 		/* Network order IP address(es) */
296 		case CD_SUBNETMASK:
297 		case CD_ROUTER_SOLICIT_SERV:
298 		case CD_BROADCASTADDR:
299 		case CD_REQUESTED_IP_ADDR:
300 		case CD_SERVER_ID:
301 			/* Single IP address */
302 			if (*start != 4) {
303 				(void) sprintf(get_line(0, 0),
304 				    "Error: Bad %s", option_types[save]);
305 			} else {
306 				start++;
307 				display_ip(1, "%s = %s", option_types[save],
308 				    &start);
309 			}
310 			break;
311 		case CD_ROUTER:
312 		case CD_TIMESERV:
313 		case CD_IEN116_NAME_SERV:
314 		case CD_DNSSERV:
315 		case CD_LOG_SERV:
316 		case CD_COOKIE_SERV:
317 		case CD_LPR_SERV:
318 		case CD_IMPRESS_SERV:
319 		case CD_RESOURCE_SERV:
320 		case CD_SWAP_SERV:
321 		case CD_NIS_SERV:
322 		case CD_NTP_SERV:
323 		case CD_NETBIOS_NAME_SERV:
324 		case CD_NETBIOS_DIST_SERV:
325 		case CD_XWIN_FONT_SERV:
326 		case CD_XWIN_DISP_SERV:
327 		case CD_NISPLUS_SERVS:
328 		case CD_MOBILE_IP_AGENT:
329 		case CD_SMTP_SERVS:
330 		case CD_POP3_SERVS:
331 		case CD_NNTP_SERVS:
332 		case CD_WWW_SERVS:
333 		case CD_FINGER_SERVS:
334 		case CD_IRC_SERVS:
335 		case CD_STREETTALK_SERVS:
336 		case CD_STREETTALK_DA_SERVS:
337 			/* Multiple IP addresses */
338 			if ((*start % 4) != 0) {
339 				(void) sprintf(get_line(0, 0),
340 				    "Error: Bad %s address",
341 				    option_types[save]);
342 			} else {
343 				items = *start++ / 4;
344 				display_ip(items, "%s at = %s",
345 				    option_types[save], &start);
346 			}
347 			break;
348 		case CD_TFTP_SERV_NAME:
349 		case CD_HOSTNAME:
350 		case CD_DUMP_FILE:
351 		case CD_DNSDOMAIN:
352 		case CD_ROOT_PATH:
353 		case CD_NIS_DOMAIN:
354 		case CD_NETBIOS_SCOPE:
355 		case CD_MESSAGE:
356 		case CD_NISPLUS_DMAIN:
357 		case CD_OPT_BOOTFILE_NAME:
358 		case CD_USER_CLASS_ID:
359 			/* Ascii strings */
360 			display_ascii("%s = %s", option_types[save], &start);
361 			break;
362 		case CD_TIMEOFFSET:
363 		case CD_IPTTL:
364 		case CD_PATH_MTU_TIMEOUT:
365 		case CD_ARP_TIMEOUT:
366 		case CD_TCP_TTL:
367 		case CD_TCP_KALIVE_INTVL:
368 		case CD_T1_TIME:
369 		case CD_T2_TIME:
370 		case CD_LEASE_TIME:
371 			/* Number: seconds */
372 			display_number("%s = %d seconds", option_types[save],
373 			    &start);
374 			break;
375 		case CD_IP_FORWARDING_ON:
376 		case CD_NON_LCL_ROUTE_ON:
377 		case CD_ALL_SUBNETS_LCL_ON:
378 		case CD_MASK_DISCVRY_ON:
379 		case CD_MASK_SUPPLIER_ON:
380 		case CD_ROUTER_DISCVRY_ON:
381 		case CD_TRAILER_ENCAPS_ON:
382 		case CD_ETHERNET_ENCAPS_ON:
383 		case CD_TCP_KALIVE_GRBG_ON:
384 			/* Number:  hex flag */
385 			display_number("%s flag = 0x%x", option_types[save],
386 			    &start);
387 			break;
388 		case CD_MAXIPSIZE:
389 		case CD_MTU:
390 		case CD_MAX_DHCP_SIZE:
391 			/* Number: bytes */
392 			display_number("%s = %d bytes", option_types[save],
393 			    &start);
394 			break;
395 		case CD_CLASS_ID:
396 		case CD_CLIENT_ID:
397 		case CD_NW_IP_DOMAIN:
398 		case CD_NW_IP_OPTIONS:
399 			/* Hex ascii strings */
400 			display_ascii_hex(option_types[save], &start);
401 			break;
402 		case CD_BOOT_SIZE:
403 			display_number("%s = %d 512 byte blocks",
404 			    "Boot file size", &start);
405 			break;
406 		case CD_POLICY_FILTER:
407 			if ((*start % 8) != 0) {
408 				(void) sprintf(get_line(0, 0),
409 				    "Error: Bad Policy Filter option");
410 			} else {
411 				items = *start++ / 8;
412 				for (i = 0; i < items; i++) {
413 					display_ip(1,
414 					    "%s = %s",
415 					    "Policy Destination",
416 					    &start);
417 					display_ip(1, "%s = %s", "Mask",
418 					    &start);
419 				}
420 			}
421 			break;
422 		case CD_PATH_MTU_TABLE_SZ:
423 			if (*start % 2 != 0) {
424 				(void) sprintf(get_line(0, 0),
425 				    "Error: Bad Path MTU Table");
426 			} else {
427 				(void) sprintf(get_line(0, 0),
428 				    "\tPath MTU Plateau Table:");
429 				(void) sprintf(get_line(0, 0),
430 				    "\t=======================");
431 				items = *start / sizeof (ushort_t);
432 				++start;
433 				for (i = 0; i < items; i++) {
434 					if (IS_P2ALIGNED(start,
435 							sizeof (ushort_t))) {
436 						/* LINTED: improper alignment */
437 						s_buf = *(ushort_t *)start;
438 					} else {
439 						memcpy((char *)&s_buf,
440 						    start, sizeof (short));
441 					}
442 					(void) sprintf(get_line(0, 0),
443 					    "\t\tEntry %d:\t\t%d", i,
444 					    ntohs(s_buf));
445 					start += sizeof (ushort_t);
446 				}
447 			}
448 			break;
449 		case CD_STATIC_ROUTE:
450 			if ((*start % 8) != 0) {
451 				(void) sprintf(get_line(0, 0),
452 				    "Error: Bad Static Route option: %d",
453 				    *start);
454 			} else {
455 				items = *start++ / 8;
456 				for (i = 0; i < items; i++) {
457 					memcpy((char *)&tmp, start,
458 					    sizeof (struct in_addr));
459 					(void) strcpy(scratch, inet_ntoa(tmp));
460 					start += sizeof (ulong_t);
461 					memcpy((char *)&tmp, start,
462 					    sizeof (struct in_addr));
463 					(void) sprintf(get_line(0, 0),
464 					    "Static route from %s to %s",
465 					    scratch, inet_ntoa(tmp));
466 					start += sizeof (ulong_t);
467 				}
468 			}
469 			break;
470 		case CD_VENDOR_SPEC:
471 			i = *start++;
472 			(void) sprintf(get_line(0, 0),
473 			    "Vendor-specific Options (%d total octets):", i);
474 			/*
475 			 * We don't know what these things are, so just
476 			 * display the option number, length, and value
477 			 * (hex).
478 			 */
479 			vend = (uchar_t *)((uchar_t *)start + i);
480 			while (start < vend && *start != CD_END) {
481 				if (*start == CD_PAD) {
482 					start++;
483 					continue;
484 				}
485 				(void) sprintf(scratch,
486 				    "\t(%.2d) %.2d octets", *start,
487 				    *(uchar_t *)((uchar_t *)start + 1));
488 				start++;
489 				display_ascii_hex(scratch, &start);
490 			}
491 			start = vend;	/* in case CD_END found */
492 			break;
493 		case CD_NETBIOS_NODE_TYPE:
494 			if (*start != 1) {
495 				(void) sprintf(get_line(0, 0),
496 				    "Error: Bad '%s' parameter",
497 				    option_types[CD_NETBIOS_NODE_TYPE]);
498 			} else {
499 				char *type;
500 				start++;
501 				switch (*start) {
502 				case 0x1:
503 					type = "Broadcast Node";
504 					break;
505 				case 0x2:
506 					type = "Point To Point Node";
507 					break;
508 				case 0x4:
509 					type = "Mixed Mode Node";
510 					break;
511 				case 0x8:
512 					type = "Hybrid Node";
513 					break;
514 				default:
515 					type = "??? Node";
516 					break;
517 				};
518 				(void) sprintf(get_line(0, 0),
519 				    "%s = %s (%d)",
520 				    option_types[CD_NETBIOS_NODE_TYPE],
521 				    type, *start);
522 				start++;
523 			}
524 			break;
525 		case CD_OPTION_OVERLOAD:
526 			if (*start != 1) {
527 				(void) sprintf(get_line(0, 0),
528 				    "Bad Option Overload value.");
529 			} else {
530 				start++;
531 				nooverload = *start++;
532 			}
533 			break;
534 		case CD_DHCP_TYPE:
535 			if (*start < 1 || *start > 7) {
536 				(void) sprintf(get_line(0, 0),
537 				    "Bad DHCP Message Type.");
538 			} else {
539 				start++;
540 				(void) sprintf(get_line(0, 0),
541 				    "Message type = %s",
542 				    show_msgtype(*start));
543 				start++;
544 			}
545 			break;
546 		case CD_REQUEST_LIST:
547 			opt_len = *start++;
548 			(void) sprintf(get_line(0, 0),
549 			    "Requested Options:");
550 			for (i = 0; i < opt_len; i++) {
551 				entry = NULL;
552 				if (*start < OPTIONS_ARRAY_SIZE) {
553 					prmpt = option_types[*start];
554 				} else {
555 					entry = inittab_getbycode(
556 						ITAB_CAT_STANDARD|ITAB_CAT_SITE,
557 						ITAB_CONS_SNOOP, *start);
558 					if (entry == NULL) {
559 						if (*start >= DHCP_SITE_OPT &&
560 						    *start <= DHCP_END_SITE) {
561 							prmpt = "Site Option";
562 						} else {
563 							prmpt = "Unrecognized "
564 								"Option";
565 						}
566 					} else {
567 						prmpt = entry->ds_name;
568 					}
569 				}
570 				(void) sprintf(get_line(0, 0),
571 				    "\t%2d (%s)", *start, prmpt);
572 				start++;
573 				free(entry);
574 			}
575 			break;
576 		default:
577 			opt_len = *start++;
578 			entry = inittab_getbycode(
579 					ITAB_CAT_STANDARD|ITAB_CAT_SITE,
580 					ITAB_CONS_SNOOP, save);
581 			if (entry == NULL) {
582 				if (save >= DHCP_SITE_OPT &&
583 				    save <= DHCP_END_SITE)
584 					prmpt = "Site";
585 				else
586 					prmpt = "Unrecognized";
587 				decoded_opt = NULL;
588 			} else {
589 				if (save < OPTIONS_ARRAY_SIZE) {
590 					prmpt = option_types[save];
591 				} else {
592 					prmpt = entry->ds_name;
593 				}
594 				decoded_opt = inittab_decode(entry, start,
595 						opt_len, B_TRUE);
596 			}
597 			if (decoded_opt == NULL) {
598 				(void) sprintf(get_line(0, 0),
599 				    "%s Option = %d, length = %d octets",
600 				    prmpt, save, opt_len);
601 				start--;
602 				display_ascii_hex("\tValue =", &start);
603 			} else {
604 				(void) sprintf(get_line(0, 0), "%s = %s", prmpt,
605 					decoded_opt);
606 				start += opt_len;
607 				free(decoded_opt);
608 			}
609 			free(entry);
610 			break;
611 		};
612 	}
613 	return (nooverload);
614 }
615 static char *
616 show_htype(int t)
617 {
618 	switch (t) {
619 	case 1:
620 		return ("Ethernet (10Mb)");
621 	case 2:
622 		return ("Experimental Ethernet (3MB)");
623 	case 3:
624 		return ("Amateur Radio AX.25");
625 	case 4:
626 		return ("Proteon ProNET Token Ring");
627 	case 5:
628 		return ("Chaos");
629 	case 6:
630 		return ("IEEE 802");
631 	case 7:
632 		return ("ARCNET");
633 	case 8:
634 		return ("Hyperchannel");
635 	case 9:
636 		return ("Lanstar");
637 	case 10:
638 		return ("Autonet");
639 	case 11:
640 		return ("LocalTalk");
641 	case 12:
642 		return ("LocalNet");
643 	case 13:
644 		return ("Ultra Link");
645 	case 14:
646 		return ("SMDS");
647 	case 15:
648 		return ("Frame Relay");
649 	case 16:
650 		return ("ATM");
651 	case ARPHRD_IB:
652 		return ("IPIB");
653 	};
654 	return ("UNKNOWN");
655 }
656 static const char *
657 show_msgtype(unsigned char type)
658 {
659 	/*
660 	 * note: the ordering here allows direct indexing of the table
661 	 *	 based on the RFC2131 packet type value passed in.
662 	 */
663 
664 	static const char *types[] = {
665 		"BOOTP",
666 		"DHCPDISCOVER", "DHCPOFFER",   "DHCPREQUEST", "DHCPDECLINE",
667 		"DHCPACK",    "DHCPNAK",      "DHCPRELEASE", "DHCPINFORM"
668 	};
669 
670 	if (type > (sizeof (types) / sizeof (*types)) || types[type] == NULL)
671 		return ("UNKNOWN");
672 
673 	return (types[type]);
674 }
675 static void
676 display_ip(int items, char *fmt, char *msg, unsigned char **opt)
677 {
678 	struct in_addr tmp;
679 	int i;
680 
681 	for (i = 0; i < items; i++) {
682 		memcpy((char *)&tmp, *opt, sizeof (struct in_addr));
683 		(void) sprintf(get_line(0, 0), fmt, msg, inet_ntoa(tmp));
684 		*opt += 4;
685 	}
686 }
687 static void
688 display_ascii(char *fmt, char *msg, unsigned char **opt)
689 {
690 	static unsigned char buf[256];
691 	int len = **opt;
692 	unsigned char slen = len;
693 
694 	if (len >= sizeof (buf))
695 		len = sizeof (buf) - 1;
696 	(*opt)++;
697 	memcpy(buf, *opt, len);
698 	*(unsigned char *)(buf + len) = '\0';
699 	(void) sprintf(get_line(0, 0), fmt, msg, buf);
700 	(*opt) += slen;
701 }
702 static void
703 display_number(char *fmt, char *msg, unsigned char **opt)
704 {
705 	int len = **opt;
706 	unsigned long l_buf = 0;
707 	unsigned short s_buf = 0;
708 
709 	if (len > 4) {
710 		(*opt)++;
711 		(void) sprintf(get_line(0, 0), fmt, msg, 0xdeadbeef);
712 		return;
713 	}
714 	switch (len) {
715 	case sizeof (uchar_t):
716 		(*opt)++;
717 		(void) sprintf(get_line(0, 0), fmt, msg, **opt);
718 		break;
719 	case sizeof (ushort_t):
720 		(*opt)++;
721 		if (IS_P2ALIGNED(*opt, sizeof (ushort_t)))
722 			/* LINTED: improper alignment */
723 			s_buf = *(unsigned short *)*opt;
724 		else
725 			memcpy((char *)&s_buf, *opt, len);
726 		(void) sprintf(get_line(0, 0), fmt, msg, ntohs(s_buf));
727 		break;
728 	case sizeof (ulong_t):
729 		(*opt)++;
730 		if (IS_P2ALIGNED(*opt, sizeof (ulong_t)))
731 			/* LINTED: improper alignment */
732 			l_buf = *(unsigned long *)*opt;
733 		else
734 			memcpy((char *)&l_buf, *opt, len);
735 		(void) sprintf(get_line(0, 0), fmt, msg, ntohl(l_buf));
736 		break;
737 	}
738 	(*opt) += len;
739 }
740 static void
741 display_ascii_hex(char *msg, unsigned char **opt)
742 {
743 	int printable;
744 	char	buffer[512];
745 	char  *line, *tmp, *ap, *fmt;
746 	int	i, j, len = **opt;
747 
748 	line = get_line(0, 0);
749 
750 	(*opt)++;
751 
752 	if (len >= 255) {
753 		(void) sprintf(line, "\t%s <TOO LONG>", msg);
754 		return;
755 	}
756 
757 	for (printable = 1, tmp = (char *)(*opt), ap = buffer;
758 	    tmp < (char *)&((*opt)[len]); tmp++) {
759 		if (isprint(*tmp))
760 			*ap++ = *tmp;
761 		else {
762 			*ap++ = '.';
763 			printable = 0;
764 		}
765 	}
766 	*ap = '\0';
767 
768 	if (!printable) {
769 		for (tmp = (char *)(*opt), ap = buffer;
770 		    (tmp < (char *)&((*opt)[len])) && (ap < &buffer[512]);
771 		    tmp++) {
772 			ap += sprintf(ap, "0x%02X ", *(uchar_t *)(tmp));
773 		}
774 		*(--ap) = '\0';
775 		i = ap - buffer;
776 		fmt = "%s\t%s (unprintable)";
777 	} else {
778 		i = strlen(buffer);
779 		fmt = "%s\t\"%s\"";
780 	}
781 	(*opt) += len;
782 	j = strlen(msg) + (MAXLINE / 2) - 30;
783 	if (i > j) {
784 		buffer[j - 1] = '.';
785 		buffer[j - 2] = '.';
786 		buffer[j - 3] = '.';
787 		buffer[j] = '\0';
788 	}
789 	(void) sprintf(line, fmt, msg, buffer);
790 }
791