print-bootp.c revision 263830 
1/*
2 * Copyright (c) 1988-1990
3 *      The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that:
7 * 1. Source code distributions retain the above copyright
8 *    notice and this paragraph in its entirety
9 * 2. Distributions including binary code include the above copyright
10 *    notice and this paragraph in its entirety in the documentation
11 *    or other materials provided with the distribution, and
12 * 3. Neither the name of the University nor the names of its contributors
13 *    may be used to endorse or promote products derived from this software
14 *    without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
17 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
18 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
19 *
20 * Format and print bootp packets.
21 *
22 * This file was copied from tcpdump-2.1.1 and modified.
23 * There is an e-mail list for tcpdump: <tcpdump@ee.lbl.gov>
24 *
25 * $FreeBSD: stable/10/libexec/bootpd/tools/bootptest/print-bootp.c 263830 2014-03-27 20:13:53Z brueffer $
26 */
27
28#include <stdio.h>
29
30#include <sys/param.h>
31#include <sys/types.h>
32#include <sys/socket.h>
33
34#include <sys/time.h>	/* for struct timeval in net/if.h */
35#include <net/if.h>
36#include <netinet/in.h>
37
38#include <string.h>
39#include <ctype.h>
40
41#include "bootp.h"
42#include "bootptest.h"
43
44/* These decode the vendor data. */
45extern int printfn();
46static void rfc1048_print();
47static void cmu_print();
48static void other_print();
49static void dump_hex();
50
51/*
52 * Print bootp requests
53 */
54void
55bootp_print(bp, length, sport, dport)
56	struct bootp *bp;
57	int length;
58	u_short sport, dport;
59{
60	static char tstr[] = " [|bootp]";
61	static unsigned char vm_cmu[4] = VM_CMU;
62	static unsigned char vm_rfc1048[4] = VM_RFC1048;
63	u_char *ep;
64	int vdlen;
65
66#define TCHECK(var, l) if ((u_char *)&(var) > ep - l) goto trunc
67
68	/* Note funny sized packets */
69	if (length != sizeof(struct bootp))
70		(void) printf(" [len=%d]", length);
71
72	/* 'ep' points to the end of avaible data. */
73	ep = (u_char *) snapend;
74
75	switch (bp->bp_op) {
76
77	case BOOTREQUEST:
78		/* Usually, a request goes from a client to a server */
79		if (sport != IPPORT_BOOTPC || dport != IPPORT_BOOTPS)
80			printf(" (request)");
81		break;
82
83	case BOOTREPLY:
84		/* Usually, a reply goes from a server to a client */
85		if (sport != IPPORT_BOOTPS || dport != IPPORT_BOOTPC)
86			printf(" (reply)");
87		break;
88
89	default:
90		printf(" bootp-#%d", bp->bp_op);
91	}
92
93	/* The usual hardware address type is 1 (10Mb Ethernet) */
94	if (bp->bp_htype != 1)
95		printf(" htype:%d", bp->bp_htype);
96
97	/* The usual length for 10Mb Ethernet address is 6 bytes */
98	if (bp->bp_hlen != 6)
99		printf(" hlen:%d", bp->bp_hlen);
100
101	/* Client's Hardware address */
102	if (bp->bp_hlen) {
103		register struct ether_header *eh;
104		register char *e;
105
106		TCHECK(bp->bp_chaddr[0], 6);
107		eh = (struct ether_header *) packetp;
108		if (bp->bp_op == BOOTREQUEST)
109			e = (char *) ESRC(eh);
110		else if (bp->bp_op == BOOTREPLY)
111			e = (char *) EDST(eh);
112		else
113			e = 0;
114		if (e == 0 || bcmp((char *) bp->bp_chaddr, e, 6))
115			dump_hex(bp->bp_chaddr, bp->bp_hlen);
116	}
117	/* Only print interesting fields */
118	if (bp->bp_hops)
119		printf(" hops:%d", bp->bp_hops);
120
121	if (bp->bp_xid)
122		printf(" xid:%ld", (long)ntohl(bp->bp_xid));
123
124	if (bp->bp_secs)
125		printf(" secs:%d", ntohs(bp->bp_secs));
126
127	/* Client's ip address */
128	TCHECK(bp->bp_ciaddr, sizeof(bp->bp_ciaddr));
129	if (bp->bp_ciaddr.s_addr)
130		printf(" C:%s", ipaddr_string(&bp->bp_ciaddr));
131
132	/* 'your' ip address (bootp client) */
133	TCHECK(bp->bp_yiaddr, sizeof(bp->bp_yiaddr));
134	if (bp->bp_yiaddr.s_addr)
135		printf(" Y:%s", ipaddr_string(&bp->bp_yiaddr));
136
137	/* Server's ip address */
138	TCHECK(bp->bp_siaddr, sizeof(bp->bp_siaddr));
139	if (bp->bp_siaddr.s_addr)
140		printf(" S:%s", ipaddr_string(&bp->bp_siaddr));
141
142	/* Gateway's ip address */
143	TCHECK(bp->bp_giaddr, sizeof(bp->bp_giaddr));
144	if (bp->bp_giaddr.s_addr)
145		printf(" G:%s", ipaddr_string(&bp->bp_giaddr));
146
147	TCHECK(bp->bp_sname[0], sizeof(bp->bp_sname));
148	if (*bp->bp_sname) {
149		printf(" sname:");
150		if (printfn(bp->bp_sname, ep)) {
151			fputs(tstr + 1, stdout);
152			return;
153		}
154	}
155	TCHECK(bp->bp_file[0], sizeof(bp->bp_file));
156	if (*bp->bp_file) {
157		printf(" file:");
158		if (printfn(bp->bp_file, ep)) {
159			fputs(tstr + 1, stdout);
160			return;
161		}
162	}
163	/* Don't try to decode the vendor buffer unless we're verbose */
164	if (vflag <= 0)
165		return;
166
167	vdlen = sizeof(bp->bp_vend);
168	/* Vendor data can extend to the end of the packet. */
169	if (vdlen < (ep - bp->bp_vend))
170		vdlen = (ep - bp->bp_vend);
171
172	TCHECK(bp->bp_vend[0], vdlen);
173	printf(" vend");
174	if (!bcmp(bp->bp_vend, vm_rfc1048, sizeof(u_int32)))
175		rfc1048_print(bp->bp_vend, vdlen);
176	else if (!bcmp(bp->bp_vend, vm_cmu, sizeof(u_int32)))
177		cmu_print(bp->bp_vend, vdlen);
178	else
179		other_print(bp->bp_vend, vdlen);
180
181	return;
182 trunc:
183	fputs(tstr, stdout);
184#undef TCHECK
185}
186
187/*
188 * Option description data follows.
189 * These are described in: RFC-1048, RFC-1395, RFC-1497, RFC-1533
190 *
191 * The first char of each option string encodes the data format:
192 * ?: unknown
193 * a: ASCII
194 * b: byte (8-bit)
195 * i: inet address
196 * l: int32
197 * s: short (16-bit)
198 */
199char *
200rfc1048_opts[] = {
201	/* Originally from RFC-1048: */
202	"?PAD",				/*  0: Padding - special, no data. */
203	"iSM",				/*  1: subnet mask (RFC950)*/
204	"lTZ",				/*  2: time offset, seconds from UTC */
205	"iGW",				/*  3: gateways (or routers) */
206	"iTS",				/*  4: time servers (RFC868) */
207	"iINS",				/*  5: IEN name servers (IEN116) */
208	"iDNS",				/*  6: domain name servers (RFC1035)(1034?) */
209	"iLOG",				/*  7: MIT log servers */
210	"iCS",				/*  8: cookie servers (RFC865) */
211	"iLPR",				/*  9: lpr server (RFC1179) */
212	"iIPS",				/* 10: impress servers (Imagen) */
213	"iRLP",				/* 11: resource location servers (RFC887) */
214	"aHN",				/* 12: host name (ASCII) */
215	"sBFS",				/* 13: boot file size (in 512 byte blocks) */
216
217	/* Added by RFC-1395: */
218	"aDUMP",			/* 14: Merit Dump File */
219	"aDNAM",			/* 15: Domain Name (for DNS) */
220	"iSWAP",			/* 16: Swap Server */
221	"aROOT",			/* 17: Root Path */
222
223	/* Added by RFC-1497: */
224	"aEXTF",			/* 18: Extensions Path (more options) */
225
226	/* Added by RFC-1533: (many, many options...) */
227#if 1	/* These might not be worth recognizing by name. */
228
229	/* IP Layer Parameters, per-host (RFC-1533, sect. 4) */
230	"bIP-forward",		/* 19: IP Forwarding flag */
231	"bIP-srcroute",		/* 20: IP Source Routing Enable flag */
232	"iIP-filters",		/* 21: IP Policy Filter (addr pairs) */
233	"sIP-maxudp",		/* 22: IP Max-UDP reassembly size */
234	"bIP-ttlive",		/* 23: IP Time to Live */
235	"lIP-pmtuage",		/* 24: IP Path MTU aging timeout */
236	"sIP-pmtutab",		/* 25: IP Path MTU plateau table */
237
238	/* IP parameters, per-interface (RFC-1533, sect. 5) */
239	"sIP-mtu-sz",		/* 26: IP MTU size */
240	"bIP-mtu-sl",		/* 27: IP MTU all subnets local */
241	"bIP-bcast1",		/* 28: IP Broadcast Addr ones flag */
242	"bIP-mask-d",		/* 29: IP do mask discovery */
243	"bIP-mask-s",		/* 30: IP do mask supplier */
244	"bIP-rt-dsc",		/* 31: IP do router discovery */
245	"iIP-rt-sa",		/* 32: IP router solicitation addr */
246	"iIP-routes",		/* 33: IP static routes (dst,router) */
247
248	/* Link Layer parameters, per-interface (RFC-1533, sect. 6) */
249	"bLL-trailer",		/* 34: do tralier encapsulation */
250	"lLL-arp-tmo",		/* 35: ARP cache timeout */
251	"bLL-ether2",		/* 36: Ethernet version 2 (IEEE 802.3) */
252
253	/* TCP parameters (RFC-1533, sect. 7) */
254	"bTCP-def-ttl",		/* 37: default time to live */
255	"lTCP-KA-tmo",		/* 38: keepalive time interval */
256	"bTCP-KA-junk",		/* 39: keepalive sends extra junk */
257
258	/* Application and Service Parameters (RFC-1533, sect. 8) */
259	"aNISDOM",			/* 40: NIS Domain (Sun YP) */
260	"iNISSRV",			/* 41: NIS Servers */
261	"iNTPSRV",			/* 42: NTP (time) Servers (RFC 1129) */
262	"?VSINFO",			/* 43: Vendor Specific Info (encapsulated) */
263	"iNBiosNS",			/* 44: NetBIOS Name Server (RFC-1001,1..2) */
264	"iNBiosDD",			/* 45: NetBIOS Datagram Dist. Server. */
265	"bNBiosNT",			/* 46: NetBIOS Note Type */
266	"?NBiosS",			/* 47: NetBIOS Scope */
267	"iXW-FS",			/* 48: X Window System Font Servers */
268	"iXW-DM",			/* 49: X Window System Display Managers */
269
270	/* DHCP extensions (RFC-1533, sect. 9) */
271#endif
272};
273#define	KNOWN_OPTIONS (sizeof(rfc1048_opts) / sizeof(rfc1048_opts[0]))
274
275static void
276rfc1048_print(bp, length)
277	register u_char *bp;
278	int length;
279{
280	u_char tag;
281	u_char *ep;
282	register int len;
283	u_int32 ul;
284	u_short us;
285	struct in_addr ia;
286	char *optstr;
287
288	printf("-rfc1395");
289
290	/* Step over magic cookie */
291	bp += sizeof(int32);
292	/* Setup end pointer */
293	ep = bp + length;
294	while (bp < ep) {
295		tag = *bp++;
296		/* Check for tags with no data first. */
297		if (tag == TAG_PAD)
298			continue;
299		if (tag == TAG_END)
300			return;
301		if (tag < KNOWN_OPTIONS) {
302			optstr = rfc1048_opts[tag];
303			printf(" %s:", optstr + 1);
304		} else {
305			printf(" T%d:", tag);
306			optstr = "?";
307		}
308		/* Now scan the length byte. */
309		len = *bp++;
310		if (bp + len > ep) {
311			/* truncated option */
312			printf(" |(%d>%td)", len, ep - bp);
313			return;
314		}
315		/* Print the option value(s). */
316		switch (optstr[0]) {
317
318		case 'a':				/* ASCII string */
319			printfn(bp, bp + len);
320			bp += len;
321			len = 0;
322			break;
323
324		case 's':				/* Word formats */
325			while (len >= 2) {
326				bcopy((char *) bp, (char *) &us, 2);
327				printf("%d", ntohs(us));
328				bp += 2;
329				len -= 2;
330				if (len) printf(",");
331			}
332			if (len) printf("(junk=%d)", len);
333			break;
334
335		case 'l':				/* Long words */
336			while (len >= 4) {
337				bcopy((char *) bp, (char *) &ul, 4);
338				printf("%ld", (long)ntohl(ul));
339				bp += 4;
340				len -= 4;
341				if (len) printf(",");
342			}
343			if (len) printf("(junk=%d)", len);
344			break;
345
346		case 'i':				/* INET addresses */
347			while (len >= 4) {
348				bcopy((char *) bp, (char *) &ia, 4);
349				printf("%s", ipaddr_string(&ia));
350				bp += 4;
351				len -= 4;
352				if (len) printf(",");
353			}
354			if (len) printf("(junk=%d)", len);
355			break;
356
357		case 'b':
358		default:
359			break;
360
361		}						/* switch */
362
363		/* Print as characters, if appropriate. */
364		if (len) {
365			dump_hex(bp, len);
366			if (isascii(*bp) && isprint(*bp)) {
367				printf("(");
368				printfn(bp, bp + len);
369				printf(")");
370			}
371			bp += len;
372			len = 0;
373		}
374	} /* while bp < ep */
375}
376
377static void
378cmu_print(bp, length)
379	register u_char *bp;
380	int length;
381{
382	struct cmu_vend *v;
383	u_char *ep;
384
385	printf("-cmu");
386
387	v = (struct cmu_vend *) bp;
388	if (length < sizeof(*v)) {
389		printf(" |L=%d", length);
390		return;
391	}
392	/* Setup end pointer */
393	ep = bp + length;
394
395	/* Subnet mask */
396	if (v->v_flags & VF_SMASK) {
397		printf(" SM:%s", ipaddr_string(&v->v_smask));
398	}
399	/* Default gateway */
400	if (v->v_dgate.s_addr)
401		printf(" GW:%s", ipaddr_string(&v->v_dgate));
402
403	/* Domain name servers */
404	if (v->v_dns1.s_addr)
405		printf(" DNS1:%s", ipaddr_string(&v->v_dns1));
406	if (v->v_dns2.s_addr)
407		printf(" DNS2:%s", ipaddr_string(&v->v_dns2));
408
409	/* IEN-116 name servers */
410	if (v->v_ins1.s_addr)
411		printf(" INS1:%s", ipaddr_string(&v->v_ins1));
412	if (v->v_ins2.s_addr)
413		printf(" INS2:%s", ipaddr_string(&v->v_ins2));
414
415	/* Time servers */
416	if (v->v_ts1.s_addr)
417		printf(" TS1:%s", ipaddr_string(&v->v_ts1));
418	if (v->v_ts2.s_addr)
419		printf(" TS2:%s", ipaddr_string(&v->v_ts2));
420
421}
422
423
424/*
425 * Print out arbitrary, unknown vendor data.
426 */
427
428static void
429other_print(bp, length)
430	register u_char *bp;
431	int length;
432{
433	u_char *ep;					/* end pointer */
434	u_char *zp;					/* points one past last non-zero byte */
435
436	/* Setup end pointer */
437	ep = bp + length;
438
439	/* Find the last non-zero byte. */
440	for (zp = ep; zp > bp; zp--) {
441		if (zp[-1] != 0)
442			break;
443	}
444
445	/* Print the all-zero case in a compact representation. */
446	if (zp == bp) {
447		printf("-all-zero");
448		return;
449	}
450	printf("-unknown");
451
452	/* Are there enough trailing zeros to make "00..." worthwhile? */
453	if (zp + 2 > ep)
454		zp = ep;				/* print them all normally */
455
456	/* Now just print all the non-zero data. */
457	while (bp < zp) {
458		printf(".%02X", *bp);
459		bp++;
460	}
461
462	if (zp < ep)
463		printf(".00...");
464
465	return;
466}
467
468static void
469dump_hex(bp, len)
470	u_char *bp;
471	int len;
472{
473	while (len > 0) {
474		printf("%02X", *bp);
475		bp++;
476		len--;
477		if (len) printf(".");
478	}
479}
480
481/*
482 * Local Variables:
483 * tab-width: 4
484 * c-indent-level: 4
485 * c-argdecl-indent: 4
486 * c-continued-statement-offset: 4
487 * c-continued-brace-offset: -4
488 * c-label-offset: -4
489 * c-brace-offset: 0
490 * End:
491 */
492