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/*
* Copyright 1985, 1986, 1987, 1988 by the Massachusetts Institute
* of Technology.
* For copying and distribution information, please see the file
* <Copyright.MIT>.
*
* from: kt.c,v 4.9 89/10/25 19:03:35 qjb Exp $
* $Id$
*/
#if 0
#ifndef lint
static char rcsid[] =
"$Id$";
#endif /* lint */
#endif
#include <unistd.h>
#include <string.h>
#include <stdio.h>
#include <krb.h>
#include <sys/file.h>
#include <sys/fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#ifdef TKT_SHMEM
#include <sys/param.h>
#endif
extern int krb_debug;
/*
* in_tkt() is used to initialize the ticket store. It creates the
* file to contain the tickets and writes the given user's name "pname"
* and instance "pinst" in the file. in_tkt() returns KSUCCESS on
* success, or KFAILURE if something goes wrong.
*/
int
in_tkt(pname,pinst)
char *pname;
char *pinst;
{
int tktfile;
uid_t me, metoo;
struct stat buf;
int count;
char *file = TKT_FILE;
int fd;
register int i;
char charbuf[BUFSIZ];
#ifdef TKT_SHMEM
char shmidname[MAXPATHLEN];
#endif /* TKT_SHMEM */
me = getuid ();
metoo = geteuid();
if (lstat(file,&buf) == 0) {
if (buf.st_uid != me && me == 0) {
unlink(file);
} else {
if (buf.st_uid != me || !(buf.st_mode & S_IFREG) ||
buf.st_mode & 077) {
if (krb_debug)
fprintf(stderr,"Error initializing %s",file);
return(KFAILURE);
}
/* file already exists, and permissions appear ok, so nuke it */
if ((fd = open(file, O_RDWR, 0)) < 0)
goto out; /* can't zero it, but we can still try truncating it */
bzero(charbuf, sizeof(charbuf));
for (i = 0; i < buf.st_size; i += sizeof(charbuf))
if (write(fd, charbuf, sizeof(charbuf)) != sizeof(charbuf)) {
(void) fsync(fd);
(void) close(fd);
goto out;
}
(void) fsync(fd);
(void) close(fd);
}
}
out:
/* arrange so the file is owned by the ruid
(swap real & effective uid if necessary).
This isn't a security problem, since the ticket file, if it already
exists, has the right uid (== ruid) and mode. */
if (me != metoo) {
if (setreuid(metoo, me) < 0) {
/* can't switch??? barf! */
if (krb_debug)
perror("in_tkt: setreuid");
return(KFAILURE);
} else
if (krb_debug)
printf("swapped UID's %d and %d\n",metoo,me);
}
if ((tktfile = open(file,O_CREAT | O_TRUNC | O_WRONLY,0600)) < 0) {
if (krb_debug)
fprintf(stderr,"Error initializing %s",TKT_FILE);
return(KFAILURE);
}
if (me != metoo) {
if (setreuid(me, metoo) < 0) {
/* can't switch??? barf! */
if (krb_debug)
perror("in_tkt: setreuid2");
return(KFAILURE);
} else
if (krb_debug)
printf("swapped UID's %d and %d\n",me,metoo);
}
if (lstat(file,&buf) < 0) {
if (krb_debug)
fprintf(stderr,"Error initializing %s",TKT_FILE);
return(KFAILURE);
}
if (buf.st_uid != me || !(buf.st_mode & S_IFREG) ||
buf.st_mode & 077) {
if (krb_debug)
fprintf(stderr,"Error initializing %s",TKT_FILE);
return(KFAILURE);
}
count = strlen(pname)+1;
if (write(tktfile,pname,count) != count) {
(void) close(tktfile);
return(KFAILURE);
}
count = strlen(pinst)+1;
if (write(tktfile,pinst,count) != count) {
(void) close(tktfile);
return(KFAILURE);
}
(void) close(tktfile);
#ifdef TKT_SHMEM
(void) strcpy(shmidname, file);
(void) strcat(shmidname, ".shm");
return(krb_shm_create(shmidname));
#else /* !TKT_SHMEM */
return(KSUCCESS);
#endif /* TKT_SHMEM */
}
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