/*	$OpenBSD: get_cred.c,v 1.4 1997/12/22 15:02:05 art Exp $	*/
/* $KTH: get_cred.c,v 1.6 1997/05/30 17:38:29 bg Exp $ */

/*
 * This software may now be redistributed outside the US.
 *
 */

/* 
 *  Copyright (C) 1989 by the Massachusetts Institute of Technology
 *
 *  Export of this software from the United States of America is assumed
 *  to require a specific license from the United States Government.
 *  It is the responsibility of any person or organization contemplating
 *  export to obtain such a license before exporting.
 *
 * WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
 * distribute this software and its documentation for any purpose and
 * without fee is hereby granted, provided that the above copyright
 * notice appear in all copies and that both that copyright notice and
 * this permission notice appear in supporting documentation, and that
 * the name of M.I.T. not be used in advertising or publicity pertaining
 * to distribution of the software without specific, written prior
 * permission.  M.I.T. makes no representations about the suitability of
 * this software for any purpose.  It is provided "as is" without express
 * or implied warranty.
 *
 */


#include "krb_locl.h"

/*
 * krb_get_cred takes a service name, instance, and realm, and a
 * structure of type CREDENTIALS to be filled in with ticket
 * information.  It then searches the ticket file for the appropriate
 * ticket and fills in the structure with the corresponding
 * information from the file.  If successful, it returns KSUCCESS.
 * On failure it returns a Kerberos error code.
 */

int
krb_get_cred(char *service,	/* Service name */
	     char *instance,	/* Instance */
	     char *realm,	/* Auth domain */
	     CREDENTIALS *c)	/* Credentials struct */
{
    int tf_status;              /* return value of tf function calls */
    CREDENTIALS cr;

    if (c == NULL)
        c = &cr;

    /* Open ticket file and lock it for shared reading */
    if ((tf_status = tf_init(TKT_FILE, R_TKT_FIL)) != KSUCCESS)
	return(tf_status);

    /* Copy principal's name and instance into the CREDENTIALS struc c */

    if ( (tf_status = tf_get_pname(c->pname)) != KSUCCESS ||
    	 (tf_status = tf_get_pinst(c->pinst)) != KSUCCESS )
	return (tf_status);

    /* Search for requested service credentials and copy into c */
       
    while ((tf_status = tf_get_cred(c)) == KSUCCESS) {
	if ((strcmp(c->service,service) == 0) &&
           (strcmp(c->instance,instance) == 0) &&
           (strcmp(c->realm,realm) == 0))
		   break;
    }
    tf_close();

    if (tf_status == EOF)
	return (GC_NOTKT);
    return(tf_status);
}