print-bootp.c revision 1.22 
1/*	$OpenBSD: print-bootp.c,v 1.22 2015/12/22 21:01:07 mmcc Exp $	*/
2
3/*
4 * Copyright (c) 1990, 1991, 1993, 1994, 1995, 1996, 1997
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that: (1) source code distributions
9 * retain the above copyright notice and this paragraph in its entirety, (2)
10 * distributions including binary code include the above copyright notice and
11 * this paragraph in its entirety in the documentation or other materials
12 * provided with the distribution, and (3) all advertising materials mentioning
13 * features or use of this software display the following acknowledgement:
14 * ``This product includes software developed by the University of California,
15 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
16 * the University nor the names of its contributors may be used to endorse
17 * or promote products derived from this software without specific prior
18 * written permission.
19 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
20 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
21 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
22 *
23 * Format and print bootp packets.
24 */
25#include <sys/time.h>
26#include <sys/socket.h>
27
28struct mbuf;
29struct rtentry;
30#include <net/if.h>
31
32#include <netinet/in.h>
33#include <netinet/if_ether.h>
34
35#include <ctype.h>
36#include <stdio.h>
37#include <string.h>
38
39#include "interface.h"
40#include "addrtoname.h"
41#include "bootp.h"
42
43static void rfc1048_print(const u_char *, u_int);
44static void cmu_print(const u_char *, u_int);
45
46static char tstr[] = " [|bootp]";
47
48/*
49 * Print bootp requests
50 */
51void
52bootp_print(const u_char *cp, u_int length,
53	    u_short sport, u_short dport)
54{
55	const struct bootp *bp;
56	static u_char vm_cmu[4] = VM_CMU;
57	static u_char vm_rfc1048[4] = VM_RFC1048;
58
59	bp = (struct bootp *)cp;
60	TCHECK(bp->bp_op);
61	switch (bp->bp_op) {
62
63	case BOOTREQUEST:
64		/* Usually, a request goes from a client to a server */
65		if (sport != IPPORT_BOOTPC || dport != IPPORT_BOOTPS)
66			printf(" (request)");
67		break;
68
69	case BOOTREPLY:
70		/* Usually, a reply goes from a server to a client */
71		if (sport != IPPORT_BOOTPS || dport != IPPORT_BOOTPC)
72			printf(" (reply)");
73		break;
74
75	default:
76		printf(" bootp-#%d", bp->bp_op);
77	}
78
79	TCHECK(bp->bp_flags);
80
81	/* The usual hardware address type is 1 (10Mb Ethernet) */
82	if (bp->bp_htype != 1)
83		printf(" htype-#%d", bp->bp_htype);
84
85	/* The usual length for 10Mb Ethernet address is 6 bytes */
86	if (bp->bp_htype != 1 || bp->bp_hlen != 6)
87		printf(" hlen:%d", bp->bp_hlen);
88
89	/* Only print interesting fields */
90	if (bp->bp_hops)
91		printf(" hops:%d", bp->bp_hops);
92	if (bp->bp_xid)
93		printf(" xid:0x%x", (u_int32_t)ntohl(bp->bp_xid));
94	if (bp->bp_secs)
95		printf(" secs:%d", ntohs(bp->bp_secs));
96	if (bp->bp_flags)
97		printf(" flags:0x%x", ntohs(bp->bp_flags));
98
99	/* Client's ip address */
100	TCHECK(bp->bp_ciaddr);
101	if (bp->bp_ciaddr.s_addr)
102		printf(" C:%s", ipaddr_string(&bp->bp_ciaddr));
103
104	/* 'your' ip address (bootp client) */
105	TCHECK(bp->bp_yiaddr);
106	if (bp->bp_yiaddr.s_addr)
107		printf(" Y:%s", ipaddr_string(&bp->bp_yiaddr));
108
109	/* Server's ip address */
110	TCHECK(bp->bp_siaddr);
111	if (bp->bp_siaddr.s_addr)
112		printf(" S:%s", ipaddr_string(&bp->bp_siaddr));
113
114	/* Gateway's ip address */
115	TCHECK(bp->bp_giaddr);
116	if (bp->bp_giaddr.s_addr)
117		printf(" G:%s", ipaddr_string(&bp->bp_giaddr));
118
119	/* Client's Ethernet address */
120	if (bp->bp_htype == 1 && bp->bp_hlen == 6) {
121		const struct ether_header *eh;
122		const char *e;
123
124		TCHECK2(bp->bp_chaddr[0], 6);
125		eh = (struct ether_header *)packetp;
126		if (bp->bp_op == BOOTREQUEST)
127			e = (const char *)ESRC(eh);
128		else if (bp->bp_op == BOOTREPLY)
129			e = (const char *)EDST(eh);
130		else
131			e = NULL;
132		if (e == 0 || memcmp((char *)bp->bp_chaddr, e, 6) != 0)
133			printf(" ether %s", etheraddr_string(bp->bp_chaddr));
134	}
135
136	TCHECK2(bp->bp_sname[0], 1);		/* check first char only */
137	if (*bp->bp_sname) {
138		printf(" sname \"");
139		if (fn_print(bp->bp_sname, snapend)) {
140			putchar('"');
141			fputs(tstr + 1, stdout);
142			return;
143		}
144		putchar('"');
145	}
146	TCHECK2(bp->bp_file[0], 1);		/* check first char only */
147	if (*bp->bp_file) {
148		printf(" file \"");
149		if (fn_print(bp->bp_file, snapend)) {
150			putchar('"');
151			fputs(tstr + 1, stdout);
152			return;
153		}
154		putchar('"');
155	}
156
157	/* Decode the vendor buffer */
158	TCHECK2(bp->bp_vend[0], sizeof(u_int32_t));
159	length -= sizeof(*bp) - sizeof(bp->bp_vend);
160	if (memcmp((char *)bp->bp_vend, (char *)vm_rfc1048,
161		 sizeof(u_int32_t)) == 0)
162		rfc1048_print(bp->bp_vend, length);
163	else if (memcmp((char *)bp->bp_vend, (char *)vm_cmu,
164		      sizeof(u_int32_t)) == 0)
165		cmu_print(bp->bp_vend, length);
166	else {
167		u_int32_t ul;
168
169		memcpy((char *)&ul, (char *)bp->bp_vend, sizeof(ul));
170		if (ul != 0)
171			printf("vend-#0x%x", ul);
172	}
173
174	return;
175trunc:
176	fputs(tstr, stdout);
177}
178
179/* The first character specifies the format to print */
180static struct tok tag2str[] = {
181/* RFC1048 tags */
182	{ TAG_PAD,		" PAD" },
183	{ TAG_SUBNET_MASK,	"iSM" },	/* subnet mask (RFC950) */
184	{ TAG_TIME_OFFSET,	"lTZ" },	/* seconds from UTC */
185	{ TAG_GATEWAY,		"iDG" },	/* default gateway */
186	{ TAG_TIME_SERVER,	"iTS" },	/* time servers (RFC868) */
187	{ TAG_NAME_SERVER,	"iIEN" },	/* IEN name servers (IEN116) */
188	{ TAG_DOMAIN_SERVER,	"iNS" },	/* domain name (RFC1035) */
189	{ TAG_LOG_SERVER,	"iLOG" },	/* MIT log servers */
190	{ TAG_COOKIE_SERVER,	"iCS" },	/* cookie servers (RFC865) */
191	{ TAG_LPR_SERVER,	"iLPR" },	/* lpr server (RFC1179) */
192	{ TAG_IMPRESS_SERVER,	"iIM" },	/* impress servers (Imagen) */
193	{ TAG_RLP_SERVER,	"iRL" },	/* resource location (RFC887) */
194	{ TAG_HOSTNAME,		"aHN" },	/* ascii hostname */
195	{ TAG_BOOTSIZE,		"sBS" },	/* 512 byte blocks */
196	{ TAG_END,		" END" },
197/* RFC1497 tags */
198	{ TAG_DUMPPATH,		"aDP" },
199	{ TAG_DOMAINNAME,	"aDN" },
200	{ TAG_SWAP_SERVER,	"iSS" },
201	{ TAG_ROOTPATH,		"aRP" },
202	{ TAG_EXTPATH,		"aEP" },
203/* RFC2132 tags */
204	{ TAG_IP_FORWARD,	"BIPF" },
205	{ TAG_NL_SRCRT,		"BSRT" },
206	{ TAG_PFILTERS,		"pPF" },
207	{ TAG_REASS_SIZE,	"sRSZ" },
208	{ TAG_DEF_TTL,		"bTTL" },
209	{ TAG_MTU_TIMEOUT,	"lMA" },
210	{ TAG_MTU_TABLE,	"sMT" },
211	{ TAG_INT_MTU,		"sMTU" },
212	{ TAG_LOCAL_SUBNETS,	"BLSN" },
213	{ TAG_BROAD_ADDR,	"iBR" },
214	{ TAG_DO_MASK_DISC,	"BMD" },
215	{ TAG_SUPPLY_MASK,	"BMS" },
216	{ TAG_DO_RDISC,		"BRD" },
217	{ TAG_RTR_SOL_ADDR,	"iRSA" },
218	{ TAG_STATIC_ROUTE,	"pSR" },
219	{ TAG_USE_TRAILERS,	"BUT" },
220	{ TAG_ARP_TIMEOUT,	"lAT" },
221	{ TAG_ETH_ENCAP,	"BIE" },
222	{ TAG_TCP_TTL,		"bTT" },
223	{ TAG_TCP_KEEPALIVE,	"lKI" },
224	{ TAG_KEEPALIVE_GO,	"BKG" },
225	{ TAG_NIS_DOMAIN,	"aYD" },
226	{ TAG_NIS_SERVERS,	"iYS" },
227	{ TAG_NTP_SERVERS,	"iNTP" },
228	{ TAG_VENDOR_OPTS,	"bVO" },
229	{ TAG_NETBIOS_NS,	"iWNS" },
230	{ TAG_NETBIOS_DDS,	"iWDD" },
231	{ TAG_NETBIOS_NODE,	"bWNT" },
232	{ TAG_NETBIOS_SCOPE,	"aWSC" },
233	{ TAG_XWIN_FS,		"iXFS" },
234	{ TAG_XWIN_DM,		"iXDM" },
235	{ TAG_NIS_P_DOMAIN,	"sN+D" },
236	{ TAG_NIS_P_SERVERS,	"iN+S" },
237	{ TAG_MOBILE_HOME,	"iMH" },
238	{ TAG_SMPT_SERVER,	"iSMTP" },
239	{ TAG_POP3_SERVER,	"iPOP3" },
240	{ TAG_NNTP_SERVER,	"iNNTP" },
241	{ TAG_WWW_SERVER,	"iWWW" },
242	{ TAG_FINGER_SERVER,	"iFG" },
243	{ TAG_IRC_SERVER,	"iIRC" },
244	{ TAG_STREETTALK_SRVR,	"iSTS" },
245	{ TAG_STREETTALK_STDA,	"iSTDA" },
246	{ TAG_REQUESTED_IP,	"iRQ" },
247	{ TAG_IP_LEASE,		"lLT" },
248	{ TAG_OPT_OVERLOAD,	"bOO" },
249	{ TAG_TFTP_SERVER,	"aTFTP" },
250	{ TAG_BOOTFILENAME,	"aBF" },
251	{ TAG_DHCP_MESSAGE,	" DHCP" },
252	{ TAG_SERVER_ID,	"iSID" },
253	{ TAG_PARM_REQUEST,	"bPR" },
254	{ TAG_MESSAGE,		"aMSG" },
255	{ TAG_MAX_MSG_SIZE,	"sMSZ" },
256	{ TAG_RENEWAL_TIME,	"lRN" },
257	{ TAG_REBIND_TIME,	"lRB" },
258	{ TAG_VENDOR_CLASS,	"bVC" },
259	{ TAG_CLIENT_ID,	"bCID" },
260	{ 0,			NULL }
261};
262
263static void
264rfc1048_print(const u_char *bp, u_int length)
265{
266	u_char tag;
267	u_int len, size;
268	const char *cp;
269	u_char c;
270	int first;
271	u_int32_t ul;
272	u_short us;
273
274	printf(" vend-rfc1048");
275
276	/* Step over magic cookie */
277	bp += sizeof(int32_t);
278
279	/* Loop while we there is a tag left in the buffer */
280	while (bp + 1 < snapend) {
281		tag = *bp++;
282		if (tag == TAG_PAD)
283			continue;
284		if (tag == TAG_END)
285			return;
286		cp = tok2str(tag2str, "?T%d", tag);
287		c = *cp++;
288		printf(" %s:", cp);
289
290		/* Get the length; check for truncation */
291		if (bp + 1 >= snapend) {
292			fputs(tstr, stdout);
293			return;
294		}
295		len = *bp++;
296		if (bp + len >= snapend) {
297			fputs(tstr, stdout);
298			return;
299		}
300
301		if (tag == TAG_DHCP_MESSAGE && len == 1) {
302			c = *bp++;
303			switch (c) {
304			case DHCPDISCOVER:	printf("DISCOVER");	break;
305			case DHCPOFFER:		printf("OFFER");	break;
306			case DHCPREQUEST:	printf("REQUEST");	break;
307			case DHCPDECLINE:	printf("DECLINE");	break;
308			case DHCPACK:		printf("ACK");		break;
309			case DHCPNAK:		printf("NACK");		break;
310			case DHCPRELEASE:	printf("RELEASE");	break;
311			case DHCPINFORM:	printf("INFORM");	break;
312			default:		printf("%u", c);	break;
313			}
314			continue;
315		}
316
317		if (tag == TAG_PARM_REQUEST) {
318			first = 1;
319			while (len-- > 0) {
320				c = *bp++;
321				cp = tok2str(tag2str, "?%d", c);
322				if (!first)
323					putchar('+');
324				printf("%s", cp + 1);
325				first = 0;
326			}
327			continue;
328		}
329
330		/* Print data */
331		size = len;
332		if (c == '?') {
333			/* Base default formats for unknown tags on data size */
334			if (size & 1)
335				c = 'b';
336			else if (size & 2)
337				c = 's';
338			else
339				c = 'l';
340		}
341		first = 1;
342		switch (c) {
343
344		case 'a':
345			/* ascii strings */
346			putchar('"');
347			(void)fn_printn(bp, size, NULL);
348			putchar('"');
349			bp += size;
350			size = 0;
351			break;
352
353		case 'i':
354		case 'l':
355			/* ip addresses/32-bit words */
356			while (size >= sizeof(ul)) {
357				if (!first)
358					putchar(',');
359				memcpy((char *)&ul, (char *)bp, sizeof(ul));
360				if (c == 'i')
361					printf("%s", ipaddr_string(&ul));
362				else
363					printf("%u", ntohl(ul));
364				bp += sizeof(ul);
365				size -= sizeof(ul);
366				first = 0;
367			}
368			break;
369
370		case 'p':
371			/* IP address pairs */
372			while (size >= 2*sizeof(ul)) {
373				if (!first)
374					putchar(',');
375				memcpy((char *)&ul, (char *)bp, sizeof(ul));
376				printf("(%s:", ipaddr_string(&ul));
377				bp += sizeof(ul);
378				memcpy((char *)&ul, (char *)bp, sizeof(ul));
379				printf("%s)", ipaddr_string(&ul));
380				bp += sizeof(ul);
381				size -= 2*sizeof(ul);
382				first = 0;
383			}
384			break;
385
386		case 's':
387			/* shorts */
388			while (size >= sizeof(us)) {
389				if (!first)
390					putchar(',');
391				memcpy((char *)&us, (char *)bp, sizeof(us));
392				printf("%u", ntohs(us));
393				bp += sizeof(us);
394				size -= sizeof(us);
395				first = 0;
396			}
397			break;
398
399		case 'B':
400			/* boolean */
401			while (size > 0) {
402				if (!first)
403					putchar(',');
404				switch (*bp) {
405				case 0:
406					putchar('N');
407					break;
408				case 1:
409					putchar('Y');
410					break;
411				default:
412					printf("%d?", *bp);
413					break;
414				}
415				++bp;
416				--size;
417				first = 0;
418			}
419			break;
420
421		case 'b':
422		default:
423			/* Bytes */
424			while (size > 0) {
425				if (!first)
426					putchar('.');
427				printf("%d", *bp);
428				++bp;
429				--size;
430				first = 0;
431			}
432			break;
433		}
434		/* Data left over? */
435		if (size)
436			printf("[len %d]", len);
437	}
438}
439
440static void
441cmu_print(const u_char *bp, u_int length)
442{
443	const struct cmu_vend *cmu;
444	static const char fmt[] = " %s:%s";
445
446#define PRINTCMUADDR(m, s) { TCHECK(cmu->m); \
447    if (cmu->m.s_addr != 0) \
448	printf(fmt, s, ipaddr_string(&cmu->m.s_addr)); }
449
450	printf(" vend-cmu");
451	cmu = (struct cmu_vend *)bp;
452
453	/* Only print if there are unknown bits */
454	TCHECK(cmu->v_flags);
455	if ((cmu->v_flags & ~(VF_SMASK)) != 0)
456		printf(" F:0x%x", cmu->v_flags);
457	PRINTCMUADDR(v_dgate, "DG");
458	PRINTCMUADDR(v_smask, cmu->v_flags & VF_SMASK ? "SM" : "SM*");
459	PRINTCMUADDR(v_dns1, "NS1");
460	PRINTCMUADDR(v_dns2, "NS2");
461	PRINTCMUADDR(v_ins1, "IEN1");
462	PRINTCMUADDR(v_ins2, "IEN2");
463	PRINTCMUADDR(v_ts1, "TS1");
464	PRINTCMUADDR(v_ts2, "TS2");
465	return;
466
467trunc:
468	fputs(tstr, stdout);
469#undef PRINTCMUADDR
470}
471