Here are the patches to bind-4.9.5-P1 to support 
the 'noforward' directive, and instructions for
building and using a modified bind.

1.  You must '#define NOFORWARD' for the modifications 
to be enabled.  The best way to do this is to add it to 
conf/options.h, but you have to do that yourself, by hand.
You can also edit the main Makefile and add '-DNOFORWARD'
to the CPPFLAGS for your platform.

2.  Apply the patches to the files in the 'named' sub-
directory.  Assuming that your current directory is
the 'named' subdirectory and the name of this file
is noforward.patches, the syntax on Digital Unix might be:

  patch -p1 -i noforward.patches

It will, of course, depend on your platform's version of 
the patch utility.  The man pages are highly recommended.

3.  Move to the top level directory and run make.  After
it builds correctly, do a 'make install' or whatever
you need to do to get the modified 'named' executable
put in the right place.

4.  Add one or more 'noforward' directives to named.boot
as required.  For instance, if you wanted to prevent
forwarding for domain 'nutsnbolts.com' (and everything
under it), add the following line to named.boot:

	noforward	nutsnbolts.com

You might also want to exclude address->name maps.  For
example, if nutsnbolts.com corresponds to network 
192.168.0.0, you might add the following:

	noforward	168.192.in-addr.arpa

Note that you can list multiple domains in a single
'noforward' directive:

	noforward	nutsnbolts.com 168.192.in-addr.arpa

5.  Restart your server to load the new config.

That's all there is to it (in a perfect world)!

Todd.Aven@BankersTrust.Com
23 December 1996


The rest of this file is patches...

========================================================================

*** named/ns_defs.h	1996/12/23 16:11:25
--- named/ns_defs.h	1996/12/23 16:44:38
***************
*** 291,296 ****
--- 291,304 ----
  			fwdaddr;
  };
  
+ #ifdef NOFORWARD
+ struct nofwdinfo {
+ 	struct nofwdinfo	*next;
+ 	char	nofwdname[255];
+ };
+ 
+ #endif /* NOFORWARD */
+ 
  enum nameserStats {	nssRcvdR,	/* sent us an answer */
  			nssRcvdNXD,	/* sent us a negative response */
  			nssRcvdFwdR,	/* sent us a response we had to fwd */
*** named/ns_forw.c	1996/12/23 16:11:25
--- named/ns_forw.c	1996/12/23 16:44:38
***************
*** 143,148 ****
--- 143,158 ----
  	qp->q_stream = qsp;
  	qp->q_curaddr = 0;
  	qp->q_fwd = fwdtab;
+ #ifdef NOFORWARD
+ 	if(noforward(dname)) {
+ 	  qp->q_fwd = NULL;
+ 	  if (n == 0) {
+ 	    dprintf(2, (ddt, "forw: no nameservers found\n"));
+ 	    qfree(qp);
+ 	    return (FW_NOSERVER);
+ 	  }
+ 	}
+ #endif /* NOFORWARD */
  	qp->q_dfd = dfd;
  	qp->q_id = id;
  	qp->q_expire = tt.tv_sec + RETRY_TIMEOUT*2;
***************
*** 1087,1089 ****
--- 1097,1150 ----
  	}
  	free((char*)qp);
  }
+ 
+ #ifdef NOFORWARD
+ int
+ noforward(dname)
+   char *dname;
+ {
+   /* Each entry in the 'noforward' list of domains is right-align
+    * compared against the dname arg.  If a match is found, then
+    * return 1.  Otherwise, return 0.
+    * e.g.  noforward(test.dom.x.y), list={x.y} returns 1
+    *                          ^^^         ^^^
+    */
+ 
+   register struct nofwdinfo *nofwdptr;
+   register int dlen, tlen;
+   register char *tname;
+ 
+   /* Protect ourselves from lunacy */
+   if(dname == (char *)NULL) return 0;
+ 
+   /* Announce our presence */
+   dprintf(1, (ddt, "noforward: dname=%s\n", dname));
+ 
+   /* Pre-calculate the length of dname */
+   dlen = strlen(dname);
+   if(dlen == 0) return 0;	/* More lunacy-protection */
+ 
+   /* Search the noforward list (if exists) for self or parent */
+   for(nofwdptr = nofwdtab; nofwdptr; nofwdptr = nofwdptr->next) {
+     tname = nofwdptr->nofwdname;
+     dprintf(1, (ddt, "noforward: compare dname=%s, tname=%s\n",
+ 		dname, tname));
+     /* Get the length of the test name */
+     tlen = strlen(tname);
+ 
+     /* Skip if the tname is longer than the dname */
+     if (tlen > dlen) continue;
+ 
+     /* Make sure the match is only on complete labels */
+     if ((dlen != tlen) && (dname[dlen-tlen-1] != '.')) continue;
+     /* Compare the tname against the dname, right-aligned */
+     if(strcasecmp(tname, (char *)(dname+dlen-tlen)) == 0) {
+       dprintf(1, (ddt, "noforward: %s matches %s\n", dname, tname));
+       return 1;
+     }
+   }
+ 
+   /* Nothing matched */
+   return 0;
+ }
+ #endif /* NOFORWARD */
*** named/ns_glob.h	1996/12/23 16:11:25
--- named/ns_glob.h	1996/12/23 16:44:38
***************
*** 82,87 ****
--- 82,92 ----
  	/* list of forwarding hosts */
  DECL	struct fwdinfo		*fwdtab		INIT(NULL);
  
+ #ifdef NOFORWARD
+ 	/* list of zones for which we ignore forwarders */
+ DECL	struct nofwdinfo	*nofwdtab	INIT(NULL);
+ #endif /* NOFORWARD */
+ 
  	/* datagram socket */
  DECL	int			ds		INIT(-1);
  
*** named/ns_init.c	1996/12/23 16:11:25
--- named/ns_init.c	1996/12/23 16:44:38
***************
*** 83,88 ****
--- 83,92 ----
  #ifdef DEBUG
  			content_zone __P((int)),
  #endif
+ #ifdef NOFORWARD
+ 			get_noforward __P((FILE *)),
+ 			free_noforward __P((void)),
+ #endif /* NOFORWARD */
  			do_reload __P((char *, int, int)),
  			free_forwarders __P((void)),
  			ns_limit __P((const char *name, int value)),
***************
*** 169,174 ****
--- 173,181 ----
  		}
  #endif
  		free_forwarders();
+ #ifdef NOFORWARD
+ 		free_noforward();
+ #endif /* NOFORWARD */
  		free_netlist(enettab);
  #ifdef XFRNETS
  		free_netlist(&xfrnets);
***************
*** 294,299 ****
--- 301,311 ----
  		} else if (strcasecmp(buf, "forwarders") == 0) {
  			get_forwarders(fp);
  			continue;
+ #ifdef NOFORWARD
+                 } else if (strcasecmp(buf, "noforward") == 0) {
+ 			get_noforward(fp);
+ 			continue;
+ #endif /* NOFORWARD */
  		} else if (strcasecmp(buf, "slave") == 0) {
  			forward_only++;
  			continue;
***************
*** 775,780 ****
--- 787,854 ----
  	fwdtab = NULL;
  }
  
+ #ifdef NOFORWARD
+ static void
+ get_noforward(fp)
+ 	FILE *fp;
+ {
+ 	char buf[BUFSIZ];
+ 	register struct nofwdinfo *fip = NULL, *ftp = NULL;
+ 
+ 	dprintf(1, (ddt, "noforward "));
+ 
+ 	/* on mulitple noforward lines, move to end of the list */
+ 	if (nofwdtab != NULL) {
+ 		for (fip = nofwdtab; fip->next != NULL; fip = fip->next) {
+ 			;
+ 		}
+ 	}
+ 
+ 	while (getword(buf, sizeof(buf), fp, 0)) {
+ 		if (strlen(buf) == 0)
+ 			break;
+ 		dprintf(1, (ddt," %s",buf));
+ 		if (ftp == NULL)
+ 			ftp = (struct nofwdinfo *)malloc(sizeof(struct nofwdinfo));
+ 		/*TSA- Should check size of buf before copying */
+ 		strcpy(ftp->nofwdname, buf);
+ 		ftp->next = NULL;
+ 		if (nofwdtab == NULL)
+ 			nofwdtab = ftp;	/* First time only */
+ 		else
+ 			fip->next = ftp;
+ 		fip = ftp;
+ 		ftp = NULL;
+ 	}
+ 	if (ftp)
+ 		free((char *)ftp);
+ 	
+ 	dprintf(1, (ddt, "\n"));
+ #ifdef DEBUG
+ 	if (debug > 2) {
+ 		for (ftp = nofwdtab; ftp != NULL; ftp = ftp->next) {
+ 			fprintf(ddt,"ftp x%x [%s] next x%x\n",
+ 				ftp,
+ 				ftp->nofwdname,
+ 				ftp->next);
+ 		}
+ 	}
+ #endif
+ }
+ 
+ static void
+ free_noforward()
+ {
+ 	register struct nofwdinfo *ftp, *fnext;
+ 
+ 	for (ftp = nofwdtab; ftp != NULL; ftp = fnext) {
+ 		fnext = ftp->next;
+ 		free((char *)ftp);
+ 	}
+ 	nofwdtab = NULL;
+ }
+ #endif /* NOFORWARD */
+ 
  static struct zoneinfo *
  find_zone(name, type, class) 
  	char *name;
*** named/ns_resp.c	1996/12/23 16:11:25
--- named/ns_resp.c	1996/12/23 16:44:38
***************
*** 1098,1103 ****
--- 1098,1106 ----
  	qp->q_naddr = 0;
  	qp->q_curaddr = 0;
  	qp->q_fwd = fwdtab;
+ #ifdef NOFORWARD
+ 	if(noforward(dname)) qp->q_fwd = NULL;
+ #endif /* NOFORWARD */
  
  	getname(np, tmpdomain, sizeof tmpdomain);
  	qp->q_domain = strdup(tmpdomain);
***************
*** 2015,2020 ****
--- 2018,2026 ----
  		qp->q_fwd = NULL;
  	else
  		qp->q_fwd = fwdtab;
+ #ifdef NOFORWARD
+ 	if(noforward(dname)) qp->q_fwd = NULL;
+ #endif /* NOFORWARD */
  	qp->q_expire = tt.tv_sec + RETRY_TIMEOUT*2;
  	qp->q_flags |= Q_SYSTEM;