2 * Written by Atsushi Murai <amurai@spec.co.jp>
3 * Copyright (c) 1998, System Planning and Engineering Co.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
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.
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
27 * $FreeBSD: src/lib/libalias/alias_nbt.c,v 1.4.2.3 2001/08/01 09:52:26 obrien Exp $
28 * $DragonFly: src/lib/libalias/alias_nbt.c,v 1.4 2006/03/18 19:43:18 swildner Exp $
32 * oConsidering for word alignment for other platform.
35 alias_nbt.c performs special processing for NetBios over TCP/IP
38 Initial version: May, 1998 (Atsushi Murai <amurai@spec.co.jp>)
40 See HISTORY file for record of revisions.
44 #include <sys/param.h>
48 #include <netinet/in_systm.h>
49 #include <netinet/in.h>
50 #include <arpa/inet.h>
51 #include <netinet/ip.h>
52 #include <netinet/udp.h>
53 #include <netinet/tcp.h>
55 #include "alias_local.h"
58 struct in_addr oldaddr;
60 struct in_addr newaddr;
69 struct in_addr source_ip;
83 u_short dir:1, opcode:4, nmflags:7, rcode:4;
99 static void PrintRcode( u_char rcode ) {
103 printf("\nFormat Error.");
105 printf("\nSever failure.");
107 printf("\nUnsupported request error.\n");
109 printf("\nRefused error.\n");
111 printf("\nActive error.\n");
113 printf("\nName in conflict error.\n");
115 printf("\n??\?=%0x\n", rcode );
122 /* Handling Name field */
123 static u_char *AliasHandleName ( u_char *p, char *pmax ) {
131 /* Following length field */
133 if (p == NULL || (char *)p >= pmax)
138 if ((char *)p > pmax)
140 return ((u_char *)p);
142 while ( ( *p & 0x3f) != 0x00 ) {
149 /* Get next length field */
150 p = (u_char *)(p + (*p & 0x3f) + 1);
151 if ((char *)p > pmax) {
159 if ( compress == 1 ) {
161 c = (u_char )(((((*s & 0x0f) << 4) | (*(s+1) & 0x0f)) - 0x11));
165 printf("<0x%02x>", c );
181 /* Set up to out of Name field */
182 if (p == NULL || (char *)p >= pmax)
186 return ((u_char *)p);
190 * NetBios Datagram Handler (IP/UDP)
192 #define DGM_DIRECT_UNIQ 0x10
193 #define DGM_DIRECT_GROUP 0x11
194 #define DGM_BROADCAST 0x12
195 #define DGM_ERROR 0x13
196 #define DGM_QUERY 0x14
197 #define DGM_POSITIVE_RES 0x15
198 #define DGM_NEGATIVE_RES 0x16
200 int AliasHandleUdpNbt(
201 struct ip *pip, /* IP packet to examine/patch */
202 struct alias_link *link,
203 struct in_addr *alias_address,
211 /* Calculate data length of UDP packet */
212 uh = (struct udphdr *) ((char *) pip + (pip->ip_hl << 2));
213 pmax = (char *)uh + ntohs( uh->uh_ulen );
215 ndh = (NbtDataHeader *)((char *)uh + (sizeof (struct udphdr)));
216 if ((char *)(ndh + 1) > pmax)
219 printf("\nType=%02x,", ndh->type );
221 switch ( ndh->type ) {
222 case DGM_DIRECT_UNIQ:
223 case DGM_DIRECT_GROUP:
225 p = (u_char *)ndh + 14;
226 p = AliasHandleName ( p, pmax ); /* Source Name */
227 p = AliasHandleName ( p, pmax ); /* Destination Name */
230 p = (u_char *)ndh + 11;
233 case DGM_POSITIVE_RES:
234 case DGM_NEGATIVE_RES:
235 p = (u_char *)ndh + 10;
236 p = AliasHandleName ( p, pmax ); /* Destination Name */
239 if (p == NULL || (char *)p > pmax)
242 printf("%s:%d-->", inet_ntoa(ndh->source_ip), ntohs(ndh->source_port) );
244 /* Doing a IP address and Port number Translation */
245 if ( uh->uh_sum != 0 ) {
248 acc = ndh->source_port;
250 sptr = (u_short *) &(ndh->source_ip);
253 sptr = (u_short *) alias_address;
256 ADJUST_CHECKSUM(acc, uh->uh_sum);
258 ndh->source_ip = *alias_address;
259 ndh->source_port = alias_port;
261 printf("%s:%d\n", inet_ntoa(ndh->source_ip), ntohs(ndh->source_port) );
264 return((p == NULL) ? -1 : 0);
266 /* Question Section */
267 #define QS_TYPE_NB 0x0020
268 #define QS_TYPE_NBSTAT 0x0021
269 #define QS_CLAS_IN 0x0001
271 u_short type; /* The type of Request */
272 u_short class; /* The class of Request */
280 NBTArguments *nbtarg)
283 while ( count != 0 ) {
285 q = (NBTNsQuestion *)AliasHandleName((u_char *)q, pmax);
287 if (q == NULL || (char *)(q + 1) > pmax) {
292 /* Type and Class filed */
293 switch ( ntohs(q->type) ) {
300 printf("\nUnknown Type on Question %0x\n", ntohs(q->type) );
307 /* Set up to out of Question Section */
308 return ((u_char *)q);
311 /* Resource Record */
312 #define RR_TYPE_A 0x0001
313 #define RR_TYPE_NS 0x0002
314 #define RR_TYPE_NULL 0x000a
315 #define RR_TYPE_NB 0x0020
316 #define RR_TYPE_NBSTAT 0x0021
317 #define RR_CLAS_IN 0x0001
318 #define SizeOfNsResource 8
326 #define SizeOfNsRNB 6
328 u_short g:1, ont:2, resv:13;
333 AliasHandleResourceNB(
336 NBTArguments *nbtarg)
341 if (q == NULL || (char *)(q + 1) > pmax)
343 /* Check out a length */
344 bcount = ntohs(q->rdlen);
346 /* Forward to Resource NB position */
347 nb = (NBTNsRNB *)((u_char *)q + SizeOfNsResource);
349 /* Processing all in_addr array */
351 printf("NB rec[%s", inet_ntoa(nbtarg->oldaddr));
352 printf("->%s, %dbytes] ",inet_ntoa(nbtarg->newaddr ), bcount);
354 while ( nb != NULL && bcount != 0 ) {
355 if ((char *)(nb + 1) > pmax) {
360 printf("<%s>", inet_ntoa(nb->addr) );
362 if (!bcmp(&nbtarg->oldaddr,&nb->addr, sizeof(struct in_addr) ) ) {
363 if ( *nbtarg->uh_sum != 0 ) {
367 sptr = (u_short *) &(nb->addr);
370 sptr = (u_short *) &(nbtarg->newaddr);
373 ADJUST_CHECKSUM(acc, *nbtarg->uh_sum);
376 nb->addr = nbtarg->newaddr;
386 nb=(NBTNsRNB *)((u_char *)nb + SizeOfNsRNB);
387 bcount -= SizeOfNsRNB;
389 if (nb == NULL || (char *)(nb + 1) > pmax) {
393 return ((u_char *)nb);
396 #define SizeOfResourceA 6
402 AliasHandleResourceA(
405 NBTArguments *nbtarg)
410 if (q == NULL || (char *)(q + 1) > pmax)
413 /* Forward to Resource A position */
414 a = (NBTNsResourceA *)( (u_char *)q + sizeof(NBTNsResource) );
416 /* Check out of length */
417 bcount = ntohs(q->rdlen);
419 /* Processing all in_addr array */
421 printf("Arec [%s", inet_ntoa(nbtarg->oldaddr));
422 printf("->%s]",inet_ntoa(nbtarg->newaddr ));
424 while ( bcount != 0 ) {
425 if (a == NULL || (char *)(a + 1) > pmax)
428 printf("..%s", inet_ntoa(a->addr) );
430 if ( !bcmp(&nbtarg->oldaddr, &a->addr, sizeof(struct in_addr) ) ) {
431 if ( *nbtarg->uh_sum != 0 ) {
435 sptr = (u_short *) &(a->addr); /* Old */
438 sptr = (u_short *) &nbtarg->newaddr; /* New */
441 ADJUST_CHECKSUM(acc, *nbtarg->uh_sum);
444 a->addr = nbtarg->newaddr;
447 bcount -= SizeOfResourceA;
449 if (a == NULL || (char *)(a + 1) > pmax)
451 return ((u_char *)a);
455 u_short opcode:4, flags:8, resv:4;
459 AliasHandleResourceNULL(
462 NBTArguments *nbtarg)
464 NBTNsResourceNULL *n;
467 if (q == NULL || (char *)(q + 1) > pmax)
470 /* Forward to Resource NULL position */
471 n = (NBTNsResourceNULL *)( (u_char *)q + sizeof(NBTNsResource) );
473 /* Check out of length */
474 bcount = ntohs(q->rdlen);
476 /* Processing all in_addr array */
477 while ( bcount != 0 ) {
478 if ((char *)(n + 1) > pmax) {
483 bcount -= sizeof(NBTNsResourceNULL);
485 if ((char *)(n + 1) > pmax)
488 return ((u_char *)n);
492 AliasHandleResourceNS(
495 NBTArguments *nbtarg)
497 NBTNsResourceNULL *n;
500 if (q == NULL || (char *)(q + 1) > pmax)
503 /* Forward to Resource NULL position */
504 n = (NBTNsResourceNULL *)( (u_char *)q + sizeof(NBTNsResource) );
506 /* Check out of length */
507 bcount = ntohs(q->rdlen);
509 /* Resource Record Name Filed */
510 q = (NBTNsResource *)AliasHandleName( (u_char *)n, pmax ); /* XXX */
512 if (q == NULL || (char *)((u_char *)n + bcount) > pmax)
515 return ((u_char *)n + bcount);
520 } NBTNsResourceNBSTAT;
523 AliasHandleResourceNBSTAT(
526 NBTArguments *nbtarg)
528 NBTNsResourceNBSTAT *n;
531 if (q == NULL || (char *)(q + 1) > pmax)
534 /* Forward to Resource NBSTAT position */
535 n = (NBTNsResourceNBSTAT *)( (u_char *)q + sizeof(NBTNsResource) );
537 /* Check out of length */
538 bcount = ntohs(q->rdlen);
540 if (q == NULL || (char *)((u_char *)n + bcount) > pmax)
543 return ((u_char *)n + bcount);
554 while ( count != 0 ) {
555 /* Resource Record Name Filed */
556 q = (NBTNsResource *)AliasHandleName( (u_char *)q, pmax );
558 if (q == NULL || (char *)(q + 1) > pmax)
561 printf("type=%02x, count=%d\n", ntohs(q->type), count );
564 /* Type and Class filed */
565 switch ( ntohs(q->type) ) {
567 q = (NBTNsResource *)AliasHandleResourceNB(
574 q = (NBTNsResource *)AliasHandleResourceA(
581 q = (NBTNsResource *)AliasHandleResourceNS(
588 q = (NBTNsResource *)AliasHandleResourceNULL(
595 q = (NBTNsResource *)AliasHandleResourceNBSTAT(
604 "\nUnknown Type of Resource %0x\n",
613 return ((u_char *)q);
616 int AliasHandleUdpNbtNS(
617 struct ip *pip, /* IP packet to examine/patch */
618 struct alias_link *link,
619 struct in_addr *alias_address,
621 struct in_addr *original_address,
622 u_short *original_port )
630 /* Set up Common Parameter */
631 nbtarg.oldaddr = *alias_address;
632 nbtarg.oldport = *alias_port;
633 nbtarg.newaddr = *original_address;
634 nbtarg.newport = *original_port;
636 /* Calculate data length of UDP packet */
637 uh = (struct udphdr *) ((char *) pip + (pip->ip_hl << 2));
638 nbtarg.uh_sum = &(uh->uh_sum);
639 nsh = (NbtNSHeader *)((char *)uh + (sizeof(struct udphdr)));
640 p = (u_char *)(nsh + 1);
641 pmax = (char *)uh + ntohs( uh->uh_ulen );
643 if ((char *)(nsh + 1) > pmax)
647 printf(" [%s] ID=%02x, op=%01x, flag=%02x, rcode=%01x, qd=%04x"
648 ", an=%04x, ns=%04x, ar=%04x, [%d]-->",
649 nsh->dir ? "Response": "Request",
658 (u_char *)p -(u_char *)nsh
662 /* Question Entries */
663 if (ntohs(nsh->qdcount) !=0 ) {
664 p = AliasHandleQuestion(
672 /* Answer Resource Records */
673 if (ntohs(nsh->ancount) !=0 ) {
674 p = AliasHandleResource(
682 /* Authority Resource Recodrs */
683 if (ntohs(nsh->nscount) !=0 ) {
684 p = AliasHandleResource(
692 /* Additional Resource Recodrs */
693 if (ntohs(nsh->arcount) !=0 ) {
694 p = AliasHandleResource(
703 PrintRcode(nsh->rcode);
705 return ((p == NULL) ? -1 : 0);