>Number:         1851
>Category:       misc
>Synopsis:       Patch that adds ability to zero out a user's skey key
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    misc-bug-people (Misc Bug People)
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Tue Dec 19 16:50:02 1995
>Last-Modified:
>Originator:     Todd C. Miller
>Organization:
Todd C. Miller   Sysadmin--University of Colorado   Todd.Miller@cs.colorado.edu
>Release:        NetBSD-current as of 12/17/95
>Environment:
System: NetBSD scrap.cs.colorado.edu 1.1A NetBSD 1.1A (PEECEE) #1: Mon Dec 18 15:09:44 MST 1995 millert@scrap.cs.colorado.edu:/usr/src/sys/arch/i386/compile/PEECEE i386
libskey.a
skeyinit

>Description:
	There is no way to remove a key from the skeykeys database
	without editing the file directly.  The enclosed patch adds
	a "-z" (zero) flag to skeyinit allowing users to zero out
	their keys (it actually just comments out the entries).
	The prevous patch I sent in did the wrong thing if the
	user had no entry in /etc/skeykeys.  Please disregard the
	older patch.
>How-To-Repeat:
	n/a
>Fix:
*** src/usr.bin/skeyinit/skeyinit.1.DIST	Fri Oct 13 21:24:50 1995
--- src/usr.bin/skeyinit/skeyinit.1	Tue Dec 19 13:44:20 1995
***************
*** 10,15 ****
--- 10,16 ----
  .Sh SYNOPSIS
  .Nm skeyinit
  .Op Fl s
+ .Op Fl z
  .Op Ar user
  .Sh DESCRIPTION
  .Nm skeyinit
***************
*** 28,33 ****
--- 29,36 ----
  in another window to generate the correct 6 english words
  for that count and seed.
  You can then "cut-and-paste" or type the words into the skeyinit window.
+ .It Fl z
+ allows the user to zero their S/Key entry.
  .It Ar user
  the username to be changed/added. By default the current user is
  operated on.
*** src/usr.bin/skeyinit/skeyinit.c.DIST	Fri Oct 13 21:24:51 1995
--- src/usr.bin/skeyinit/skeyinit.c	Tue Dec 19 14:11:16 1995
***************
*** 29,41 ****
  #define NAMELEN 2
  
  int skeylookup __ARGS((struct skey * mp, char *name));
  
  int
  main(argc, argv)
  	int     argc;
  	char   *argv[];
  {
! 	int     rval, n, nn, i, defaultsetup, l;
  	time_t  now;
  	char	hostname[MAXHOSTNAMELEN];
  	char    seed[18], tmp[80], key[8], defaultseed[17];
--- 29,42 ----
  #define NAMELEN 2
  
  int skeylookup __ARGS((struct skey * mp, char *name));
+ int skeyzero __ARGS((struct skey * mp, char *name));
  
  int
  main(argc, argv)
  	int     argc;
  	char   *argv[];
  {
! 	int     rval, n, nn, i, defaultsetup, l, zerokey = 0;
  	time_t  now;
  	char	hostname[MAXHOSTNAMELEN];
  	char    seed[18], tmp[80], key[8], defaultseed[17];
***************
*** 63,76 ****
  		err(1, "Who are you?");
  
  	defaultsetup = 1;
! 	if (argc > 1) {
! 		if (strcmp("-s", argv[1]) == 0)
  			defaultsetup = 0;
! 		else
! 			pp = getpwnam(argv[1]);
! 
! 		if (argc > 2)
! 			pp = getpwnam(argv[2]);
  	}
  	if (pp == NULL) {
  		err(1, "User unknown");
--- 64,78 ----
  		err(1, "Who are you?");
  
  	defaultsetup = 1;
! 	for (i=1; i < argc; i++) {
! 		if (strcmp("-s", argv[i]) == 0)
  			defaultsetup = 0;
! 		else if (strcmp("-z", argv[i]) == 0)
! 			zerokey = 1;
! 		else {
! 			pp = getpwnam(argv[i]);
! 			break;
! 		}
  	}
  	if (pp == NULL) {
  		err(1, "User unknown");
***************
*** 104,109 ****
--- 106,115 ----
  	case -1:
  		err(1, "cannot open database");
  	case 0:
+ 		/* comment out user if asked to */
+ 		if (zerokey)
+ 			exit(skeyzero(&skey, pp->pw_name));
+ 
  		printf("[Updating %s]\n", pp->pw_name);
  		printf("Old key: %s\n", skey.seed);
  
***************
*** 127,132 ****
--- 133,142 ----
  		}
  		break;
  	case 1:
+ 		if (zerokey) {
+ 			printf("You have no entry to zero.\n");
+ 			exit(1);
+ 		}
  		printf("[Adding %s]\n", pp->pw_name);
  		break;
  	}
*** src/lib/libskey/skeylogin.c.DIST	Fri Oct 13 19:03:42 1995
--- src/lib/libskey/skeylogin.c	Mon Dec 18 22:39:20 1995
***************
*** 364,366 ****
--- 364,394 ----
  	}
  	return -1;
  }
+ 
+ /* Comment out user's entry in the s/key database
+  *
+  * Return codes:
+  * -1: Write error; database unchanged
+  *  0:  Database updated
+  *
+  * The database file is always closed by this call.
+  */
+ int
+ skeyzero(mp,response)
+ 	struct skey *mp;
+ 	char *response;
+ {
+ 	/*
+ 	 * Seek to the right place and write comment character
+ 	 * which effectively zero's out the entry.
+ 	 */
+ 	fseek(mp->keyfile,mp->recstart,0);
+ 	if (fputc('#', mp->keyfile) == EOF) {
+ 		fclose(mp->keyfile);
+ 		return -1;
+ 	}
+ 
+ 	fclose(mp->keyfile);
+ 	
+ 	return 0;
+ }
>Audit-Trail:
>Unformatted: