alias_nbt.c@ 21864

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1	/*-
2	* Written by Atsushi Murai <[email protected]>
3	* Copyright (c) 1998, System Planning and Engineering Co.
4	* All rights reserved.
5	*
6	* Redistribution and use in source and binary forms, with or without
7	* modification, are permitted provided that the following conditions
8	* are met:
9	* 1. Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.
11	* 2. Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.
14	*
15	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18	* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25	* SUCH DAMAGE.
26	* TODO:
27	* oClean up.
28	* oConsidering for word alignment for other platform.
29	*/
30
31	#ifndef VBOX
32	#include <sys/cdefs.h>
33	__FBSDID("$FreeBSD: src/sys/netinet/libalias/alias_nbt.c,v 1.20.8.1 2009/04/15 03:14:26 kensmith Exp $");
34
35	/*
36	alias_nbt.c performs special processing for NetBios over TCP/IP
37	sessions by UDP.
38
39	Initial version: May, 1998 (Atsushi Murai <[email protected]>)
40
41	See HISTORY file for record of revisions.
42	*/
43
44	/* Includes */
45	#ifdef _KERNEL
46	#include <sys/param.h>
47	#include <sys/systm.h>
48	#include <sys/kernel.h>
49	#include <sys/module.h>
50	#else
51	#include <errno.h>
52	#include <sys/types.h>
53	#include <stdio.h>
54	#endif
55
56	#include <netinet/in_systm.h>
57	#include <netinet/in.h>
58	#include <netinet/ip.h>
59	#include <netinet/udp.h>
60
61	#ifdef _KERNEL
62	#include <netinet/libalias/alias_local.h>
63	#include <netinet/libalias/alias_mod.h>
64	#else
65	#include "alias_local.h"
66	#include "alias_mod.h"
67	#endif
68	#else /VBOX/
69	# include <iprt/ctype.h>
70	# include <slirp.h>
71	# include "alias_local.h"
72	# include "alias_mod.h"
73	#endif /VBOX/
74
75	#define NETBIOS_NS_PORT_NUMBER 137
76	#define NETBIOS_DGM_PORT_NUMBER 138
77
78	static int
79	AliasHandleUdpNbt(struct libalias , struct ip , struct alias_link *,
80	struct in_addr *, u_short);
81
82	static int
83	AliasHandleUdpNbtNS(struct libalias , struct ip , struct alias_link *,
84	struct in_addr , u_short , struct in_addr , u_short );
85	static int
86	fingerprint1(struct libalias la, struct ip pip, struct alias_data *ah)
87	{
88
89	if (ah->dport == NULL \|\| ah->sport == NULL \|\| ah->lnk == NULL \|\|
90	ah->aaddr == NULL \|\| ah->aport == NULL)
91	return (-1);
92	if (ntohs(*ah->dport) == NETBIOS_DGM_PORT_NUMBER
93	\|\| ntohs(*ah->sport) == NETBIOS_DGM_PORT_NUMBER)
94	return (0);
95	return (-1);
96	}
97
98	static int
99	protohandler1(struct libalias la, struct ip pip, struct alias_data *ah)
100	{
101
102	AliasHandleUdpNbt(la, pip, ah->lnk, ah->aaddr, *ah->aport);
103	return (0);
104	}
105
106	static int
107	fingerprint2(struct libalias la, struct ip pip, struct alias_data *ah)
108	{
109
110	if (ah->dport == NULL \|\| ah->sport == NULL \|\| ah->lnk == NULL \|\|
111	ah->aaddr == NULL \|\| ah->aport == NULL)
112	return (-1);
113	if (ntohs(*ah->dport) == NETBIOS_NS_PORT_NUMBER
114	\|\| ntohs(*ah->sport) == NETBIOS_NS_PORT_NUMBER)
115	return (0);
116	return (-1);
117	}
118
119	static int
120	protohandler2in(struct libalias la, struct ip pip, struct alias_data *ah)
121	{
122
123	AliasHandleUdpNbtNS(la, pip, ah->lnk, ah->aaddr, ah->aport,
124	ah->oaddr, ah->dport);
125	return (0);
126	}
127
128	static int
129	protohandler2out(struct libalias la, struct ip pip, struct alias_data *ah)
130	{
131
132	AliasHandleUdpNbtNS(la, pip, ah->lnk, &pip->ip_src, ah->sport,
133	ah->aaddr, ah->aport);
134	return (0);
135	}
136
137	/* Kernel module definition. */
138	#ifndef VBOX
139	struct proto_handler handlers[] = {
140	{
141	.pri = 130,
142	.dir = IN\|OUT,
143	.proto = UDP,
144	.fingerprint = &fingerprint1,
145	.protohandler = &protohandler1
146	},
147	{
148	.pri = 140,
149	.dir = IN,
150	.proto = UDP,
151	.fingerprint = &fingerprint2,
152	.protohandler = &protohandler2in
153	},
154	{
155	.pri = 140,
156	.dir = OUT,
157	.proto = UDP,
158	.fingerprint = &fingerprint2,
159	.protohandler = &protohandler2out
160	},
161	{ EOH }
162	};
163	#else /* !VBOX */
164	static struct proto_handler handlers[4];
165	#endif /VBOX/
166
167	#ifndef VBOX
168	static int
169	mod_handler(module_t mod, int type, void *data)
170	#else /!VBOX/
171	static int nbt_alias_handler(PNATState pData, int type);
172
173	int
174	nbt_alias_load(PNATState pData)
175	{
176	return nbt_alias_handler(pData, MOD_LOAD);
177	}
178
179	int
180	nbt_alias_unload(PNATState pData)
181	{
182	return nbt_alias_handler(pData, MOD_UNLOAD);
183	}
184	static int
185	nbt_alias_handler(PNATState pData, int type)
186	#endif /VBOX/
187	{
188	int error;
189	#ifdef VBOX
190
191	handlers[0].pri = 130;
192	handlers[0].dir = IN\|OUT;
193	handlers[0].proto = UDP;
194	handlers[0].fingerprint = &fingerprint1;
195	handlers[0].protohandler = &protohandler1;
196
197
198	handlers[1].pri = 140;
199	handlers[1].dir = IN;
200	handlers[1].proto = UDP;
201	handlers[1].fingerprint = &fingerprint2;
202	handlers[1].protohandler = &protohandler2in;
203
204
205	handlers[2].pri = 140;
206	handlers[2].dir = OUT;
207	handlers[2].proto = UDP;
208	handlers[2].fingerprint = &fingerprint2;
209	handlers[2].protohandler = &protohandler2out;
210
211	handlers[3].pri = EOH;
212	#endif /VBOX/
213
214	switch (type) {
215	case MOD_LOAD:
216	error = 0;
217	#ifdef VBOX
218	LibAliasAttachHandlers(pData, handlers);
219	#else
220	LibAliasAttachHandlers(handlers);
221	#endif
222	break;
223	case MOD_UNLOAD:
224	error = 0;
225	#ifdef VBOX
226	LibAliasDetachHandlers(pData, handlers);
227	#else
228	LibAliasDetachHandlers(handlers);
229	#endif
230	break;
231	default:
232	error = EINVAL;
233	}
234	return (error);
235	}
236
237	#ifndef VBOX
238	#ifdef _KERNEL
239	static
240	#endif
241	moduledata_t alias_mod = {
242	"alias_nbt", mod_handler, NULL
243	};
244	#endif /!VBOX/
245
246	#ifdef _KERNEL
247	DECLARE_MODULE(alias_nbt, alias_mod, SI_SUB_DRIVERS, SI_ORDER_SECOND);
248	MODULE_VERSION(alias_nbt, 1);
249	MODULE_DEPEND(alias_nbt, libalias, 1, 1, 1);
250	#endif
251
252	typedef struct {
253	struct in_addr oldaddr;
254	u_short oldport;
255	struct in_addr newaddr;
256	u_short newport;
257	u_short *uh_sum;
258	} NBTArguments;
259
260	typedef struct {
261	unsigned char type;
262	unsigned char flags;
263	u_short id;
264	struct in_addr source_ip;
265	u_short source_port;
266	u_short len;
267	u_short offset;
268	} NbtDataHeader;
269
270	#define OpQuery 0
271	#define OpUnknown 4
272	#define OpRegist 5
273	#define OpRelease 6
274	#define OpWACK 7
275	#define OpRefresh 8
276	typedef struct {
277	u_short nametrid;
278	u_short dir: 1, opcode:4, nmflags:7, rcode:4;
279	u_short qdcount;
280	u_short ancount;
281	u_short nscount;
282	u_short arcount;
283	} NbtNSHeader;
284
285	#define FMT_ERR 0x1
286	#define SRV_ERR 0x2
287	#define IMP_ERR 0x4
288	#define RFS_ERR 0x5
289	#define ACT_ERR 0x6
290	#define CFT_ERR 0x7
291
292
293	#ifdef LIBALIAS_DEBUG
294	static void
295	PrintRcode(u_char rcode)
296	{
297
298	switch (rcode) {
299	case FMT_ERR:
300	printf("\nFormat Error.");
301	case SRV_ERR:
302	printf("\nSever failure.");
303	case IMP_ERR:
304	printf("\nUnsupported request error.\n");
305	case RFS_ERR:
306	printf("\nRefused error.\n");
307	case ACT_ERR:
308	printf("\nActive error.\n");
309	case CFT_ERR:
310	printf("\nName in conflict error.\n");
311	default:
312	printf("\n?%c?=%0x\n", '?', rcode);
313
314	}
315	}
316
317	#endif
318
319
320	/* Handling Name field */
321	static u_char *
322	AliasHandleName(u_char * p, char *pmax)
323	{
324
325	u_char *s;
326	u_char c;
327	int compress;
328
329	/* Following length field */
330
331	if (p == NULL \|\| (char *)p >= pmax)
332	return (NULL);
333
334	if (*p & 0xc0) {
335	p = p + 2;
336	if ((char *)p > pmax)
337	return (NULL);
338	return ((u_char *) p);
339	}
340	while ((*p & 0x3f) != 0x00) {
341	s = p + 1;
342	if (*p == 0x20)
343	compress = 1;
344	else
345	compress = 0;
346
347	/* Get next length field */
348	p = (u_char ) (p + (p & 0x3f) + 1);
349	if ((char *)p > pmax) {
350	p = NULL;
351	break;
352	}
353	#ifdef LIBALIAS_DEBUG
354	printf(":");
355	#endif
356	while (s < p) {
357	if (compress == 1) {
358	c = (u_char) (((((s & 0x0f) << 4) \| ((s + 1) & 0x0f)) - 0x11));
359	#ifdef LIBALIAS_DEBUG
360	if (isprint(c))
361	printf("%c", c);
362	else
363	printf("<0x%02x>", c);
364	#endif
365	s += 2;
366	} else {
367	#ifdef LIBALIAS_DEBUG
368	printf("%c", *s);
369	#endif
370	s++;
371	}
372	}
373	#ifdef LIBALIAS_DEBUG
374	printf(":");
375	fflush(stdout);
376	#endif
377	}
378
379	/* Set up to out of Name field */
380	if (p == NULL \|\| (char *)p >= pmax)
381	p = NULL;
382	else
383	p++;
384	return ((u_char *) p);
385	}
386
387	/*
388	* NetBios Datagram Handler (IP/UDP)
389	*/
390	#define DGM_DIRECT_UNIQ 0x10
391	#define DGM_DIRECT_GROUP 0x11
392	#define DGM_BROADCAST 0x12
393	#define DGM_ERROR 0x13
394	#define DGM_QUERY 0x14
395	#define DGM_POSITIVE_RES 0x15
396	#define DGM_NEGATIVE_RES 0x16
397
398	static int
399	AliasHandleUdpNbt(
400	struct libalias *la,
401	struct ip pip, / IP packet to examine/patch */
402	struct alias_link *lnk,
403	struct in_addr *alias_address,
404	u_short alias_port
405	)
406	{
407	struct udphdr *uh;
408	NbtDataHeader *ndh;
409	u_char *p = NULL;
410	char *pmax;
411
412	(void)la;
413	(void)lnk;
414
415	/* Calculate data length of UDP packet */
416	uh = (struct udphdr *)ip_next(pip);
417	pmax = (char *)uh + ntohs(uh->uh_ulen);
418
419	ndh = (NbtDataHeader *)udp_next(uh);
420	if ((char *)(ndh + 1) > pmax)
421	return (-1);
422	#ifdef LIBALIAS_DEBUG
423	printf("\nType=%02x,", ndh->type);
424	#endif
425	switch (ndh->type) {
426	case DGM_DIRECT_UNIQ:
427	case DGM_DIRECT_GROUP:
428	case DGM_BROADCAST:
429	p = (u_char *) ndh + 14;
430	p = AliasHandleName(p, pmax); /* Source Name */
431	p = AliasHandleName(p, pmax); /* Destination Name */
432	break;
433	case DGM_ERROR:
434	p = (u_char *) ndh + 11;
435	break;
436	case DGM_QUERY:
437	case DGM_POSITIVE_RES:
438	case DGM_NEGATIVE_RES:
439	p = (u_char *) ndh + 10;
440	p = AliasHandleName(p, pmax); /* Destination Name */
441	break;
442	}
443	if (p == NULL \|\| (char *)p > pmax)
444	p = NULL;
445	#ifdef LIBALIAS_DEBUG
446	printf("%s:%d-->", inet_ntoa(ndh->source_ip), ntohs(ndh->source_port));
447	#endif
448	/* Doing an IP address and Port number Translation */
449	if (uh->uh_sum != 0) {
450	int acc;
451	u_short *sptr;
452
453	acc = ndh->source_port;
454	acc -= alias_port;
455	sptr = (u_short *) & (ndh->source_ip);
456	acc += *sptr++;
457	acc += *sptr;
458	sptr = (u_short *) alias_address;
459	acc -= *sptr++;
460	acc -= *sptr;
461	ADJUST_CHECKSUM(acc, uh->uh_sum);
462	}
463	ndh->source_ip = *alias_address;
464	ndh->source_port = alias_port;
465	#ifdef LIBALIAS_DEBUG
466	printf("%s:%d\n", inet_ntoa(ndh->source_ip), ntohs(ndh->source_port));
467	fflush(stdout);
468	#endif
469	return ((p == NULL) ? -1 : 0);
470	}
471
472	/* Question Section */
473	#define QS_TYPE_NB 0x0020
474	#define QS_TYPE_NBSTAT 0x0021
475	#define QS_CLAS_IN 0x0001
476	typedef struct {
477	u_short type; /* The type of Request */
478	u_short class; /* The class of Request */
479	} NBTNsQuestion;
480
481	static u_char *
482	AliasHandleQuestion(
483	u_short count,
484	NBTNsQuestion * q,
485	char *pmax,
486	NBTArguments * nbtarg)
487	{
488
489	(void)nbtarg;
490
491	while (count != 0) {
492	/* Name Filed */
493	q = (NBTNsQuestion ) AliasHandleName((u_char ) q, pmax);
494
495	if (q == NULL \|\| (char *)(q + 1) > pmax) {
496	q = NULL;
497	break;
498	}
499	/* Type and Class filed */
500	switch (ntohs(q->type)) {
501	case QS_TYPE_NB:
502	case QS_TYPE_NBSTAT:
503	q = q + 1;
504	break;
505	default:
506	#ifdef LIBALIAS_DEBUG
507	printf("\nUnknown Type on Question %0x\n", ntohs(q->type));
508	#endif
509	break;
510	}
511	count--;
512	}
513
514	/* Set up to out of Question Section */
515	return ((u_char *) q);
516	}
517
518	/* Resource Record */
519	#define RR_TYPE_A 0x0001
520	#define RR_TYPE_NS 0x0002
521	#define RR_TYPE_NULL 0x000a
522	#define RR_TYPE_NB 0x0020
523	#define RR_TYPE_NBSTAT 0x0021
524	#define RR_CLAS_IN 0x0001
525	#define SizeOfNsResource 8
526	typedef struct {
527	u_short type;
528	u_short class;
529	unsigned int ttl;
530	u_short rdlen;
531	} NBTNsResource;
532
533	#define SizeOfNsRNB 6
534	typedef struct {
535	u_short g: 1 , ont:2, resv:13;
536	struct in_addr addr;
537	} NBTNsRNB;
538
539	static u_char *
540	AliasHandleResourceNB(
541	NBTNsResource * q,
542	char *pmax,
543	NBTArguments * nbtarg)
544	{
545	NBTNsRNB *nb;
546	u_short bcount;
547
548	if (q == NULL \|\| (char *)(q + 1) > pmax)
549	return (NULL);
550	/* Check out a length */
551	bcount = ntohs(q->rdlen);
552
553	/* Forward to Resource NB position */
554	nb = (NBTNsRNB ) ((u_char ) q + SizeOfNsResource);
555
556	/* Processing all in_addr array */
557	#ifdef LIBALIAS_DEBUG
558	printf("NB rec[%s", inet_ntoa(nbtarg->oldaddr));
559	printf("->%s, %dbytes] ", inet_ntoa(nbtarg->newaddr), bcount);
560	#endif
561	while (nb != NULL && bcount != 0) {
562	if ((char *)(nb + 1) > pmax) {
563	nb = NULL;
564	break;
565	}
566	#ifdef LIBALIAS_DEBUG
567	printf("<%s>", inet_ntoa(nb->addr));
568	#endif
569	if (!bcmp(&nbtarg->oldaddr, &nb->addr, sizeof(struct in_addr))) {
570	if (*nbtarg->uh_sum != 0) {
571	int acc;
572	u_short *sptr;
573
574	sptr = (u_short *) & (nb->addr);
575	acc = *sptr++;
576	acc += *sptr;
577	sptr = (u_short *) & (nbtarg->newaddr);
578	acc -= *sptr++;
579	acc -= *sptr;
580	ADJUST_CHECKSUM(acc, *nbtarg->uh_sum);
581	}
582	nb->addr = nbtarg->newaddr;
583	#ifdef LIBALIAS_DEBUG
584	printf("O");
585	#endif
586	}
587	#ifdef LIBALIAS_DEBUG
588	else {
589	printf(".");
590	}
591	#endif
592	nb = (NBTNsRNB ) ((u_char ) nb + SizeOfNsRNB);
593	bcount -= SizeOfNsRNB;
594	}
595	if (nb == NULL \|\| (char *)(nb + 1) > pmax) {
596	nb = NULL;
597	}
598	return ((u_char *) nb);
599	}
600
601	#define SizeOfResourceA 6
602	typedef struct {
603	struct in_addr addr;
604	} NBTNsResourceA;
605
606	static u_char *
607	AliasHandleResourceA(
608	NBTNsResource * q,
609	char *pmax,
610	NBTArguments * nbtarg)
611	{
612	NBTNsResourceA *a;
613	u_short bcount;
614
615	if (q == NULL \|\| (char *)(q + 1) > pmax)
616	return (NULL);
617
618	/* Forward to Resource A position */
619	a = (NBTNsResourceA ) ((u_char ) q + sizeof(NBTNsResource));
620
621	/* Check out of length */
622	bcount = ntohs(q->rdlen);
623
624	/* Processing all in_addr array */
625	#ifdef LIBALIAS_DEBUG
626	printf("Arec [%s", inet_ntoa(nbtarg->oldaddr));
627	printf("->%s]", inet_ntoa(nbtarg->newaddr));
628	#endif
629	while (bcount != 0) {
630	if (a == NULL \|\| (char *)(a + 1) > pmax)
631	return (NULL);
632	#ifdef LIBALIAS_DEBUG
633	printf("..%s", inet_ntoa(a->addr));
634	#endif
635	if (!bcmp(&nbtarg->oldaddr, &a->addr, sizeof(struct in_addr))) {
636	if (*nbtarg->uh_sum != 0) {
637	int acc;
638	u_short *sptr;
639
640	sptr = (u_short ) & (a->addr); / Old */
641	acc = *sptr++;
642	acc += *sptr;
643	sptr = (u_short ) & nbtarg->newaddr; / New */
644	acc -= *sptr++;
645	acc -= *sptr;
646	ADJUST_CHECKSUM(acc, *nbtarg->uh_sum);
647	}
648	a->addr = nbtarg->newaddr;
649	}
650	a++; /* XXXX */
651	bcount -= SizeOfResourceA;
652	}
653	if (a == NULL \|\| (char *)(a + 1) > pmax)
654	a = NULL;
655	return ((u_char *) a);
656	}
657
658	typedef struct {
659	u_short opcode:4, flags:8, resv:4;
660	} NBTNsResourceNULL;
661
662	static u_char *
663	AliasHandleResourceNULL(
664	NBTNsResource * q,
665	char *pmax,
666	NBTArguments * nbtarg)
667	{
668	NBTNsResourceNULL *n;
669	u_short bcount;
670
671	(void)nbtarg;
672
673	if (q == NULL \|\| (char *)(q + 1) > pmax)
674	return (NULL);
675
676	/* Forward to Resource NULL position */
677	n = (NBTNsResourceNULL ) ((u_char ) q + sizeof(NBTNsResource));
678
679	/* Check out of length */
680	bcount = ntohs(q->rdlen);
681
682	/* Processing all in_addr array */
683	while (bcount != 0) {
684	if ((char *)(n + 1) > pmax) {
685	n = NULL;
686	break;
687	}
688	n++;
689	bcount -= sizeof(NBTNsResourceNULL);
690	}
691	if ((char *)(n + 1) > pmax)
692	n = NULL;
693
694	return ((u_char *) n);
695	}
696
697	static u_char *
698	AliasHandleResourceNS(
699	NBTNsResource * q,
700	char *pmax,
701	NBTArguments * nbtarg)
702	{
703	NBTNsResourceNULL *n;
704	u_short bcount;
705
706	(void)nbtarg;
707
708	if (q == NULL \|\| (char *)(q + 1) > pmax)
709	return (NULL);
710
711	/* Forward to Resource NULL position */
712	n = (NBTNsResourceNULL ) ((u_char ) q + sizeof(NBTNsResource));
713
714	/* Check out of length */
715	bcount = ntohs(q->rdlen);
716
717	/* Resource Record Name Filed */
718	q = (NBTNsResource ) AliasHandleName((u_char ) n, pmax); /* XXX */
719
720	if (q == NULL \|\| (char )((u_char ) n + bcount) > pmax)
721	return (NULL);
722	else
723	return ((u_char *) n + bcount);
724	}
725
726	typedef struct {
727	u_short numnames;
728	} NBTNsResourceNBSTAT;
729
730	static u_char *
731	AliasHandleResourceNBSTAT(
732	NBTNsResource * q,
733	char *pmax,
734	NBTArguments * nbtarg)
735	{
736	NBTNsResourceNBSTAT *n;
737	u_short bcount;
738
739	(void)nbtarg;
740
741	if (q == NULL \|\| (char *)(q + 1) > pmax)
742	return (NULL);
743
744	/* Forward to Resource NBSTAT position */
745	n = (NBTNsResourceNBSTAT ) ((u_char ) q + sizeof(NBTNsResource));
746
747	/* Check out of length */
748	bcount = ntohs(q->rdlen);
749
750	if (q == NULL \|\| (char )((u_char ) n + bcount) > pmax)
751	return (NULL);
752	else
753	return ((u_char *) n + bcount);
754	}
755
756	static u_char *
757	AliasHandleResource(
758	u_short count,
759	NBTNsResource * q,
760	char *pmax,
761	NBTArguments
762	* nbtarg)
763	{
764	while (count != 0) {
765	/* Resource Record Name Filed */
766	q = (NBTNsResource ) AliasHandleName((u_char ) q, pmax);
767
768	if (q == NULL \|\| (char *)(q + 1) > pmax)
769	break;
770	#ifdef LIBALIAS_DEBUG
771	printf("type=%02x, count=%d\n", ntohs(q->type), count);
772	#endif
773
774	/* Type and Class filed */
775	switch (ntohs(q->type)) {
776	case RR_TYPE_NB:
777	q = (NBTNsResource *) AliasHandleResourceNB(
778	q,
779	pmax,
780	nbtarg
781	);
782	break;
783	case RR_TYPE_A:
784	q = (NBTNsResource *) AliasHandleResourceA(
785	q,
786	pmax,
787	nbtarg
788	);
789	break;
790	case RR_TYPE_NS:
791	q = (NBTNsResource *) AliasHandleResourceNS(
792	q,
793	pmax,
794	nbtarg
795	);
796	break;
797	case RR_TYPE_NULL:
798	q = (NBTNsResource *) AliasHandleResourceNULL(
799	q,
800	pmax,
801	nbtarg
802	);
803	break;
804	case RR_TYPE_NBSTAT:
805	q = (NBTNsResource *) AliasHandleResourceNBSTAT(
806	q,
807	pmax,
808	nbtarg
809	);
810	break;
811	default:
812	#ifdef LIBALIAS_DEBUG
813	printf(
814	"\nUnknown Type of Resource %0x\n",
815	ntohs(q->type)
816	);
817	fflush(stdout);
818	#endif
819	break;
820	}
821	count--;
822	}
823	return ((u_char *) q);
824	}
825
826	static int
827	AliasHandleUdpNbtNS(
828	struct libalias *la,
829	struct ip pip, / IP packet to examine/patch */
830	struct alias_link *lnk,
831	struct in_addr *alias_address,
832	u_short * alias_port,
833	struct in_addr *original_address,
834	u_short * original_port)
835	{
836	struct udphdr *uh;
837	NbtNSHeader *nsh;
838	u_char *p;
839	char *pmax;
840	NBTArguments nbtarg;
841
842	(void)la;
843	(void)lnk;
844
845	/* Set up Common Parameter */
846	nbtarg.oldaddr = *alias_address;
847	nbtarg.oldport = *alias_port;
848	nbtarg.newaddr = *original_address;
849	nbtarg.newport = *original_port;
850
851	/* Calculate data length of UDP packet */
852	uh = (struct udphdr *)ip_next(pip);
853	nbtarg.uh_sum = &(uh->uh_sum);
854	nsh = (NbtNSHeader *)udp_next(uh);
855	p = (u_char *) (nsh + 1);
856	pmax = (char *)uh + ntohs(uh->uh_ulen);
857
858	if ((char *)(nsh + 1) > pmax)
859	return (-1);
860
861	#ifdef LIBALIAS_DEBUG
862	printf(" [%s] ID=%02x, op=%01x, flag=%02x, rcode=%01x, qd=%04x"
863	", an=%04x, ns=%04x, ar=%04x, [%d]-->",
864	nsh->dir ? "Response" : "Request",
865	nsh->nametrid,
866	nsh->opcode,
867	nsh->nmflags,
868	nsh->rcode,
869	ntohs(nsh->qdcount),
870	ntohs(nsh->ancount),
871	ntohs(nsh->nscount),
872	ntohs(nsh->arcount),
873	(u_char ) p - (u_char ) nsh
874	);
875	#endif
876
877	/* Question Entries */
878	if (ntohs(nsh->qdcount) != 0) {
879	p = AliasHandleQuestion(
880	ntohs(nsh->qdcount),
881	(NBTNsQuestion *) p,
882	pmax,
883	&nbtarg
884	);
885	}
886	/* Answer Resource Records */
887	if (ntohs(nsh->ancount) != 0) {
888	p = AliasHandleResource(
889	ntohs(nsh->ancount),
890	(NBTNsResource *) p,
891	pmax,
892	&nbtarg
893	);
894	}
895	/* Authority Resource Recodrs */
896	if (ntohs(nsh->nscount) != 0) {
897	p = AliasHandleResource(
898	ntohs(nsh->nscount),
899	(NBTNsResource *) p,
900	pmax,
901	&nbtarg
902	);
903	}
904	/* Additional Resource Recodrs */
905	if (ntohs(nsh->arcount) != 0) {
906	p = AliasHandleResource(
907	ntohs(nsh->arcount),
908	(NBTNsResource *) p,
909	pmax,
910	&nbtarg
911	);
912	}
913	#ifdef LIBALIAS_DEBUG
914	PrintRcode(nsh->rcode);
915	#endif
916	return ((p == NULL) ? -1 : 0);
917	}

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source: vbox/trunk/src/VBox/Devices/Network/slirp/libalias/alias_nbt.c@ 21864

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