Primary verison of NetBIOS over TCP/IP. Now you can connect Windows

DOMAIN as DOMAIN user through NAT function. See also RFC1002 for
futher detail of SMB structure.

Submitted by:	Atsushi Murai <amurai@spec.co.jp>

1 files changed, 576 insertions, 0 deletions

diff --git a/lib/libalias/alias_nbt.c b/lib/libalias/alias_nbt.c
new file mode 100644
index 0000000..f3581a7
--- /dev/null
+++ b/lib/libalias/alias_nbt.c
@@ -0,0 +1,576 @@
+/*
+ * Written by Atsushi Murai <amurai@spec.co.jp>
+ *
+ * Copyright (C) 1998, System Planning and Engineering Co. All rights reserverd.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by the System Planning and Engineering Co.  The name of the
+ * SPEC may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * $Id:$
+ *
+ *  TODO:
+ *       oClean up. 
+ *       oConsidering for word alignment for other platform.
+ */
+/*
+    alias_nbt.c performs special processing for NetBios over TCP/IP
+    sessions by UDP.
+
+    Initial version:  May, 1998  (Atsushi Murai <amurai@spec.co.jp>)
+
+    See HISTORY file for record of revisions.
+*/
+
+/* Includes */
+#include <ctype.h>
+#include <stdio.h> 
+#include <string.h>
+#include <sys/types.h>
+#include <netinet/in_systm.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <netinet/ip.h>
+#include <netinet/udp.h>
+#include <netinet/tcp.h>
+
+#include "alias_local.h"
+
+#define ADJUST_CHECKSUM(acc, cksum) { \
+    acc += cksum; \
+    if (acc < 0) \
+    { \
+        acc = -acc; \
+        acc = (acc >> 16) + (acc & 0xffff); \
+        acc += acc >> 16; \
+        cksum = (u_short) ~acc; \
+    } \
+    else \
+    { \
+        acc = (acc >> 16) + (acc & 0xffff); \
+        acc += acc >> 16; \
+        cksum = (u_short) acc; \
+    } \
+}
+
+typedef struct {
+	struct in_addr		oldaddr;
+	u_short 			oldport;
+	struct in_addr		newaddr;
+	u_short 			newport;
+	u_short 			*uh_sum;
+} NBTArguments;
+
+typedef struct {
+	unsigned char   type;
+	unsigned char   flags;
+	u_short  		id;
+	struct in_addr  source_ip;
+	u_short			source_port;
+	u_short			len;
+	u_short			offset;
+} NbtDataHeader;
+
+#define OpQuery		0
+#define OpUnknown	4
+#define OpRegist	5
+#define OpRelease	6
+#define OpWACK		7
+#define OpRefresh	8
+typedef struct {
+	u_short			nametrid;
+	u_short 		dir:1, opcode:4, nmflags:7, rcode:4;
+	u_short			qdcount;
+	u_short			ancount;
+	u_short			nscount;
+	u_short			arcount;
+} NbtNSHeader;
+
+#define FMT_ERR		0x1
+#define SRV_ERR		0x2
+#define IMP_ERR		0x4
+#define RFS_ERR		0x5
+#define ACT_ERR		0x6
+#define CFT_ERR		0x7
+
+/*******************************************************************
+ * copy an IP address from one buffer to another                   *
+ *******************************************************************/
+void putip(void *dest,void *src)
+{
+  memcpy(dest,src,4);
+}
+
+void PrintRcode( u_char rcode )  {
+
+	switch (rcode) {
+		case FMT_ERR:
+			printf("\nFormat Error.");
+		case SRV_ERR:
+			printf("\nSever failure.");
+		case IMP_ERR:
+			printf("\nUnsupported request error.\n");
+		case RFS_ERR:
+			printf("\nRefused error.\n");
+		case ACT_ERR:
+			printf("\nActive error.\n");
+		case CFT_ERR:
+			printf("\nName in conflict error.\n");
+		default:
+			printf("\n???=%0x\n", rcode );
+
+	}	
+}
+
+
+/* Handling Name field */
+u_char *AliasHandleName ( u_char *p ) {
+
+	u_char *s;
+	u_char c;
+	int		compress;
+
+	/* Following length field */
+	if (*p & 0xc0 ) {
+		p = p + 2;
+		return ((u_char *)p);
+	}
+	while ( ( *p & 0x3f) != 0x00 ) {
+		s = p + 1;
+		if ( *p == 0x20 )
+			compress = 1;
+		else
+			compress = 0;
+		
+	 	/* Get next length field */
+		p = (u_char *)(p + (*p & 0x3f) + 1);
+#ifdef DEBUG
+		printf(":");
+#endif
+		while (s < p) {
+			if ( compress == 1 ) {
+				c = (u_char )(((((*s & 0x0f) << 4) | (*(s+1) & 0x0f)) - 0x11));
+#ifdef DEBUG
+				if (isprint( c ) )
+					printf("%c", c );
+				else
+					printf("<0x%02x>", c );
+#endif
+				s +=2;
+			} else {
+#ifdef DEBUG
+				printf("%c", *s);
+#endif
+				s++;
+			}
+		}
+#ifdef DEBUG
+		printf(":");
+#endif
+		fflush(stdout);
+    }
+
+	/* Set up to out of Name field */
+	p++;
+	return ((u_char *)p);
+}
+
+/* 
+ * NetBios Datagram Handler (IP/UDP)
+ */
+#define DGM_DIRECT_UNIQ		0x10
+#define DGM_DIRECT_GROUP	0x11
+#define DGM_BROADCAST		0x12
+#define DGM_ERROR			0x13
+#define DGM_QUERY			0x14
+#define DGM_POSITIVE_RES	0x15
+#define DGM_NEGATIVE_RES	0x16
+
+void AliasHandleUdpNbt(
+	struct ip 		  	*pip,	 /* IP packet to examine/patch */
+	struct alias_link 	*link,
+	struct in_addr		*alias_address,
+	u_short 			alias_port )
+{
+    struct udphdr *	uh;
+    NbtDataHeader 	*ndh;
+	u_char			*p;
+        
+    /* Calculate data length of UDP packet */
+    uh =  (struct udphdr *) ((char *) pip + (pip->ip_hl << 2));
+	ndh = (NbtDataHeader *)((char *)uh + (sizeof (struct udphdr)));
+#ifdef DEBUG
+	printf("\nType=%02x,", ndh->type );
+#endif
+	switch ( ndh->type ) {
+		case DGM_DIRECT_UNIQ:
+		case DGM_DIRECT_GROUP:
+		case DGM_BROADCAST:
+			p = (u_char *)ndh + 14;
+			p = AliasHandleName ( p ); /* Source Name */
+			p = AliasHandleName ( p ); /* Destination Name */
+			break;
+		case DGM_ERROR:
+			p = (u_char *)ndh + 11;
+			break;
+		case DGM_QUERY:
+		case DGM_POSITIVE_RES:
+		case DGM_NEGATIVE_RES:
+			p = (u_char *)ndh + 10;
+			p = AliasHandleName ( p ); /* Destination Name */
+			break;
+	}
+#ifdef DEBUG
+	printf("%s:%d-->", inet_ntoa(ndh->source_ip), ntohs(ndh->source_port) );
+#endif
+	/* Doing a IP address and Port number Translation */
+	if ( uh->uh_sum != 0 ) {
+		int				acc;
+		u_short			*sptr;
+		acc  = ndh->source_port;
+		acc -= alias_port;
+		sptr = (u_short *) &(ndh->source_ip);
+		acc += *sptr++;
+		acc += *sptr;
+		sptr = (u_short *) alias_address;
+		acc -= *sptr++;
+		acc -= *sptr;
+		ADJUST_CHECKSUM(acc, uh->uh_sum)
+	}
+    ndh->source_ip = *alias_address;
+    ndh->source_port = alias_port;
+#ifdef DEBUG
+	printf("%s:%d\n", inet_ntoa(ndh->source_ip), ntohs(ndh->source_port) );
+	fflush(stdout);
+#endif
+}
+/* Question Section */
+#define QS_TYPE_NB		0x0020
+#define QS_TYPE_NBSTAT	0x0021
+#define QS_CLAS_IN		0x0001
+typedef struct {
+	u_short	type;	/* The type of Request */
+	u_short	class;	/* The class of Request */
+} NBTNsQuestion;
+
+u_char *AliasHandleQuestion(u_short count,
+							NBTNsQuestion *q,
+							NBTArguments  *nbtarg)
+{
+
+	while ( count != 0 ) {
+		/* Name Filed */
+		q = (NBTNsQuestion *)AliasHandleName((u_char *)q );
+
+		/* Type and Class filed */
+		switch ( ntohs(q->type) ) {
+			case QS_TYPE_NB:
+			case QS_TYPE_NBSTAT:
+				q= q+1;
+			break;
+			default:
+				printf("\nUnknown Type on Question %0x\n", ntohs(q->type) );
+			break;
+		}
+		count--;
+	}
+
+	/* Set up to out of Question Section */
+	return ((u_char *)q);
+}
+
+/* Resource Record */
+#define RR_TYPE_A		0x0001
+#define RR_TYPE_NS		0x0002
+#define RR_TYPE_NULL	0x000a
+#define RR_TYPE_NB		0x0020
+#define RR_TYPE_NBSTAT	0x0021
+#define RR_CLAS_IN		0x0001
+#define SizeOfNsResource	8
+typedef struct {
+ 	u_short type;
+ 	u_short class;
+ 	unsigned int ttl;
+ 	u_short rdlen;
+} NBTNsResource;
+
+#define SizeOfNsRNB			6
+typedef struct {
+	u_short g:1, ont:2, resv:13;
+	struct	in_addr	addr;
+} NBTNsRNB;
+
+u_char *AliasHandleResourceNB( NBTNsResource *q,
+							   NBTArguments  *nbtarg)
+{
+	NBTNsRNB	*nb;
+	u_short bcount;
+
+	/* Check out a length */
+	bcount = ntohs(q->rdlen);
+
+	/* Forward to Resource NB position */
+	nb = (NBTNsRNB *)((u_char *)q + SizeOfNsResource);
+
+	/* Processing all in_addr array */
+#ifdef DEBUG
+	printf("NB rec[%s", inet_ntoa(nbtarg->oldaddr));
+            printf("->%s, %dbytes] ",inet_ntoa(nbtarg->newaddr ), bcount);
+#endif
+	while ( bcount != 0 )  {
+#ifdef DEBUG
+		printf("<%s>", inet_ntoa(nb->addr) );
+#endif
+		if (!bcmp(&nbtarg->oldaddr,&nb->addr, sizeof(struct in_addr) ) ) {
+			if ( *nbtarg->uh_sum != 0 ) {
+            	int acc;
+            	u_short *sptr;
+
+            	sptr = (u_short *) &(nb->addr);
+            	acc = *sptr++;
+            	acc += *sptr;
+            	sptr = (u_short *) &(nbtarg->newaddr);
+            	acc -= *sptr++;
+            	acc -= *sptr;
+            	ADJUST_CHECKSUM(acc, *nbtarg->uh_sum)
+			}
+
+			nb->addr = nbtarg->newaddr;
+#ifdef DEBUG
+			printf("O");
+#endif
+		}
+#ifdef DEBUG
+		 else {
+			printf(".");
+		}
+#endif
+		nb=(NBTNsRNB *)((u_char *)nb + SizeOfNsRNB);
+	 	bcount -= SizeOfNsRNB;
+	}
+
+	return ((u_char *)nb);
+}
+
+#define SizeOfResourceA		6
+typedef struct {
+	struct	in_addr	addr;
+} NBTNsResourceA;
+
+u_char *AliasHandleResourceA( NBTNsResource *q,
+						 	  NBTArguments  *nbtarg)
+{
+	NBTNsResourceA	*a;
+	u_short bcount;
+
+	/* Forward to Resource A position */
+	a = (NBTNsResourceA *)( (u_char *)q + sizeof(NBTNsResource) );
+
+	/* Check out of length */
+	bcount = ntohs(q->rdlen);
+
+	/* Processing all in_addr array */
+#ifdef DEBUG
+	printf("Arec [%s", inet_ntoa(nbtarg->oldaddr));
+        printf("->%s]",inet_ntoa(nbtarg->newaddr ));
+#endif
+	while ( bcount != 0 )  {
+#ifdef DEBUG
+		printf("..%s", inet_ntoa(a->addr) );
+#endif
+		if ( !bcmp(&nbtarg->oldaddr, &a->addr, sizeof(struct in_addr) ) ) {
+			if ( *nbtarg->uh_sum != 0 ) {
+            	int acc;
+            	u_short *sptr;
+
+            	sptr = (u_short *) &(a->addr);		 /* Old */
+            	acc = *sptr++;
+            	acc += *sptr;
+            	sptr = (u_short *) &nbtarg->newaddr; /* New */
+            	acc -= *sptr++;
+            	acc -= *sptr;
+            	ADJUST_CHECKSUM(acc, *nbtarg->uh_sum)
+			}
+
+			a->addr = nbtarg->newaddr;
+		}
+		a++;	/*XXXX*/
+		bcount -= SizeOfResourceA;
+	}
+	return ((u_char *)a);
+}
+
+typedef struct {
+	u_short opcode:4, flags:8, resv:4;
+} NBTNsResourceNULL;
+
+u_char *AliasHandleResourceNULL( NBTNsResource *q,
+						 	     NBTArguments  *nbtarg)
+{
+	NBTNsResourceNULL	*n;
+	u_short bcount;
+
+	/* Forward to Resource NULL position */
+	n = (NBTNsResourceNULL *)( (u_char *)q + sizeof(NBTNsResource) );
+
+	/* Check out of length */
+	bcount = ntohs(q->rdlen);
+
+	/* Processing all in_addr array */
+	while ( bcount != 0 )  {
+		n++;
+		bcount -= sizeof(NBTNsResourceNULL);
+	}
+
+	return ((u_char *)n);
+}
+
+u_char *AliasHandleResourceNS( NBTNsResource *q,
+						 	     NBTArguments  *nbtarg)
+{
+	NBTNsResourceNULL	*n;
+	u_short bcount;
+
+	/* Forward to Resource NULL position */
+	n = (NBTNsResourceNULL *)( (u_char *)q + sizeof(NBTNsResource) );
+
+	/* Check out of length */
+	bcount = ntohs(q->rdlen);
+
+	/* Resource Record Name Filed */
+	q = (NBTNsResource *)AliasHandleName( (u_char *)n ); /* XXX */
+
+	return ((u_char *)n + bcount);
+}
+
+typedef struct {
+	u_short	numnames;
+} NBTNsResourceNBSTAT;
+
+u_char *AliasHandleResourceNBSTAT( NBTNsResource *q,
+						 	       NBTArguments  *nbtarg)
+{
+	NBTNsResourceNBSTAT	*n;
+	u_short bcount;
+
+	/* Forward to Resource NBSTAT position */
+	n = (NBTNsResourceNBSTAT *)( (u_char *)q + sizeof(NBTNsResource) );
+
+	/* Check out of length */
+	bcount = ntohs(q->rdlen);
+
+	return ((u_char *)n + bcount);
+}
+
+u_char *AliasHandleResource(u_short count,
+							NBTNsResource *q,
+							NBTArguments  *nbtarg)
+{
+	while ( count != 0 ) {
+		/* Resource Record Name Filed */
+		q = (NBTNsResource *)AliasHandleName( (u_char *)q );
+#ifdef DEBUG
+		printf("type=%02x, count=%d\n", ntohs(q->type), count );
+#endif
+
+		/* Type and Class filed */
+		switch ( ntohs(q->type) ) {
+			case RR_TYPE_NB:
+				q = (NBTNsResource *)AliasHandleResourceNB( q, nbtarg );
+				break;
+			case RR_TYPE_A: 
+				q = (NBTNsResource *)AliasHandleResourceA( q, nbtarg );
+				break;
+			case RR_TYPE_NS:
+				q = (NBTNsResource *)AliasHandleResourceNS( q, nbtarg );
+				break;
+			case RR_TYPE_NULL:
+				q = (NBTNsResource *)AliasHandleResourceNULL( q, nbtarg );
+				break;
+			case RR_TYPE_NBSTAT:
+				q = (NBTNsResource *)AliasHandleResourceNBSTAT( q, nbtarg );
+				break;
+			default: printf("\nUnknown Type of Resource %0x\n",
+								 ntohs(q->type) );
+				break;
+		}
+		count--;
+	}
+	fflush(stdout);
+	return ((u_char *)q);
+}
+
+void AliasHandleUdpNbtNS(
+	struct ip 		  	*pip,	 /* IP packet to examine/patch */
+	struct alias_link 	*link,
+	struct in_addr		*alias_address,
+	u_short 			*alias_port,
+	struct in_addr		*original_address,
+	u_short 			*original_port )
+{
+    struct udphdr *	uh;
+	NbtNSHeader	  * nsh;
+	u_short		    dlen;
+	u_char		  * p;
+	NBTArguments    nbtarg;
+
+	/* Set up Common Parameter */	
+	nbtarg.oldaddr	=	*alias_address;
+	nbtarg.oldport	=	*alias_port;
+	nbtarg.newaddr	=	*original_address;
+	nbtarg.newport	=	*original_port;
+
+    /* Calculate data length of UDP packet */
+    uh =  (struct udphdr *) ((char *) pip + (pip->ip_hl << 2));
+	nbtarg.uh_sum	=	&(uh->uh_sum);
+    dlen = ntohs( uh->uh_ulen );
+	nsh = (NbtNSHeader *)((char *)uh + (sizeof(struct udphdr)));
+	p = (u_char *)(nsh + 1);
+
+#ifdef DEBUG
+	printf(" [%s] ID=%02x, op=%01x, flag=%02x, rcode=%01x, qd=%04x, an=%04x, ns=%04x, ar=%04x, [%d]-->", 
+		nsh->dir ? "Response": "Request",
+		nsh->nametrid,
+		nsh->opcode,
+		nsh->nmflags,
+		nsh->rcode,
+		ntohs(nsh->qdcount),
+		ntohs(nsh->ancount),
+		ntohs(nsh->nscount),
+		ntohs(nsh->arcount),
+		(u_char *)p -(u_char *)nsh);
+#endif
+
+	/* Question Entries */
+	if (ntohs(nsh->qdcount) !=0 ) {
+	p = AliasHandleQuestion(ntohs(nsh->qdcount), (NBTNsQuestion *)p, &nbtarg );
+	}
+
+	/* Answer Resource Records */
+	if (ntohs(nsh->ancount) !=0 ) {
+	p = AliasHandleResource(ntohs(nsh->ancount), (NBTNsResource *)p, &nbtarg );
+	}
+
+	/* Authority Resource Recodrs */
+	if (ntohs(nsh->nscount) !=0 ) {
+	p = AliasHandleResource(ntohs(nsh->nscount), (NBTNsResource *)p, &nbtarg );
+	}
+
+	/* Additional Resource Recodrs */
+	if (ntohs(nsh->arcount) !=0 ) {
+	p = AliasHandleResource(ntohs(nsh->arcount), (NBTNsResource *)p, &nbtarg );
+	}
+
+#ifdef DEBUG
+	 	PrintRcode(nsh->rcode);
+#endif
+	return;
+}