Path: utzoo!attcan!uunet!lll-winken!csd4.milw.wisc.edu!mailrus!tut.cis.ohio-state.edu!bloom-beacon!bu-cs!budd
From: budd@bu-cs.BU.EDU (Philip Budne)
Newsgroups: comp.protocols.appletalk
Subject: Re: UNIX programs for reloading KFPS4s
Summary: code to get NIT interface name
Message-ID: <29629@bu-cs.BU.EDU>
Date: 14 Apr 89 22:06:46 GMT
References: <8904101849.AA00680@laotse.santafe.edu> <1358@muddy.ldgo.columbia.edu> <38612@bbn.COM> <38662@bbn.COM>
Reply-To: budd@buit2.bu.edu (Phil Budne)
Followup-To: comp.protocols.appletalk
Organization: Boston University
Lines: 76

In article <38662@bbn.COM> tappan@BBN.COM (Dan Tappan) writes:
>In article <38612@bbn.COM> tappan@BBN.COM (Dan Tappan) writes:
>>This is the second report I've heard of a crash. I suspect a bug in 
>>early versions of the NIT driver.
I gave you the first report.  The kernel dies in sendto().

>.....
>The reason for this is that the 'nitlib' has hardwired into it to use
>the 'le0' ethernet interface. The 100/200 machines use a 'ie0'
>interface and, if you access 'le0' on them, rather than returning an
>error NIT crashes the machine with a bus error.
>
>The fix is: in nitlib.c change the line
>char *nit_interface = "le0";
>to
>char *nit_interface = "ie0";

Here's a fix to get the default interface name.  Of course you still
get stuck when you have both an ie0 and an ie1.  Perhaps both aarpd
and kboot need "-i" flags?

*** nitlib.c.orig	Sun Mar 12 02:02:56 1989
--- nitlib.c	Fri Apr 14 17:57:31 1989
***************
*** 35,41 ****
  /* Global variables */
  
  /* The name of the interface to NIT on */
! char *nit_interface = "le0";
  
  /* The packet types to receive */
  int nit_type = NT_ALLTYPES;
--- 35,41 ----
  /* Global variables */
  
  /* The name of the interface to NIT on */
! char *nit_interface = NULL;		/* budd - perhaps have -i iface? */
  
  /* The packet types to receive */
  int nit_type = NT_ALLTYPES;
***************
*** 91,97 ****
--- 91,100 ----
    int fd;
    struct ifreq ifr;
    struct hostent *hp;
+   struct ifconf ifc;			/* budd */
+   char ifbuf[ 100 ];			/* budd */
  
+ 
    if (getuid() != 0) {
      fprintf(stderr, "must run as root\n");
      exit(1);
***************
*** 105,110 ****
--- 108,127 ----
      return(0);
    }
  
+   /* budd... */
+   ifc.ifc_len = sizeof( ifbuf );
+   ifc.ifc_buf = ifbuf;
+ 
+   if( nit_interface == NULL ) {
+       /* get default interface name */
+       if( ioctl(nit_socket, SIOCGIFCONF, (char *)&ifc) < 0 ) {
+ 	  perror( "nit ifconf ioctl");
+ 	  return( 0 );
+       }
+       nit_interface = ifc.ifc_req->ifr_name;
+       printf("Using interface %s\n", nit_interface );
+   }
+   /* ...budd */
    strncpy(nit_sockaddr.snit_ifname, nit_interface,
  	  sizeof(nit_sockaddr.snit_ifname));
    if (bind(nit_socket,