freebsd-dev/eBones/lib/libkrb/get_ad_tkt.c
Geoff Rehmet 60643d379b Initial import of eBones.
(Including all changes for FreeBSD - importing the original eBones distribution
would be too complex at this stage, since I don't have access to Piero's 
CVS.)
(If you want to include eBones in your system, don't forget to include
MAKE_EBONES in /etc/make.conf.)
(This stuff is now also suppable from braae.ru.ac.za.)

Bones originally from MIT SIPB.
Original port to FreeBSD 1.x  by Piero Serini.
Moved to FreeBSD 2.0 by Doug Rabson and Geoff Rehmet.
Nice bug fixes from Doug Rabson.
1994-09-30 14:50:09 +00:00

235 lines
6.5 KiB
C

/*
* Copyright 1986, 1987, 1988 by the Massachusetts Institute
* of Technology.
* For copying and distribution information, please see the file
* <Copyright.MIT>.
*
* from: get_ad_tkt.c,v 4.15 89/07/07 15:18:51 jtkohl Exp $
* $Id: get_ad_tkt.c,v 1.2 1994/07/19 19:25:11 g89r4222 Exp $
*/
#ifndef lint
static char rcsid[] =
"$Id: get_ad_tkt.c,v 1.2 1994/07/19 19:25:11 g89r4222 Exp $";
#endif /* lint */
#include <krb.h>
#include <des.h>
#include <prot.h>
#include <strings.h>
#include <stdio.h>
#include <errno.h>
/* use the bsd time.h struct defs for PC too! */
#include <sys/time.h>
#include <sys/types.h>
extern int krb_debug;
struct timeval tt_local = { 0, 0 };
int swap_bytes;
unsigned long rep_err_code;
/*
* get_ad_tkt obtains a new service ticket from Kerberos, using
* the ticket-granting ticket which must be in the ticket file.
* It is typically called by krb_mk_req() when the client side
* of an application is creating authentication information to be
* sent to the server side.
*
* get_ad_tkt takes four arguments: three pointers to strings which
* contain the name, instance, and realm of the service for which the
* ticket is to be obtained; and an integer indicating the desired
* lifetime of the ticket.
*
* It returns an error status if the ticket couldn't be obtained,
* or AD_OK if all went well. The ticket is stored in the ticket
* cache.
*
* The request sent to the Kerberos ticket-granting service looks
* like this:
*
* pkt->dat
*
* TEXT original contents of authenticator+ticket
* pkt->dat built in krb_mk_req call
*
* 4 bytes time_ws always 0 (?)
* char lifetime lifetime argument passed
* string service service name argument
* string sinstance service instance arg.
*
* See "prot.h" for the reply packet layout and definitions of the
* extraction macros like pkt_version(), pkt_msg_type(), etc.
*/
get_ad_tkt(service,sinstance,realm,lifetime)
char *service;
char *sinstance;
char *realm;
int lifetime;
{
static KTEXT_ST pkt_st;
KTEXT pkt = & pkt_st; /* Packet to KDC */
static KTEXT_ST rpkt_st;
KTEXT rpkt = &rpkt_st; /* Returned packet */
static KTEXT_ST cip_st;
KTEXT cip = &cip_st; /* Returned Ciphertext */
static KTEXT_ST tkt_st;
KTEXT tkt = &tkt_st; /* Current ticket */
C_Block ses; /* Session key for tkt */
CREDENTIALS cr;
int kvno; /* Kvno for session key */
char lrealm[REALM_SZ];
C_Block key; /* Key for decrypting cipher */
Key_schedule key_s;
long time_ws = 0;
char s_name[SNAME_SZ];
char s_instance[INST_SZ];
int msg_byte_order;
int kerror;
char rlm[REALM_SZ];
char *ptr;
unsigned long kdc_time; /* KDC time */
if ((kerror = krb_get_tf_realm(TKT_FILE, lrealm)) != KSUCCESS)
return(kerror);
/* Create skeleton of packet to be sent */
(void) gettimeofday(&tt_local,(struct timezone *) 0);
pkt->length = 0;
/*
* Look for the session key (and other stuff we don't need)
* in the ticket file for krbtgt.realm@lrealm where "realm"
* is the service's realm (passed in "realm" argument) and
* lrealm is the realm of our initial ticket. If we don't
* have this, we will try to get it.
*/
if ((kerror = krb_get_cred("krbtgt",realm,lrealm,&cr)) != KSUCCESS) {
/*
* If realm == lrealm, we have no hope, so let's not even try.
*/
if ((strncmp(realm, lrealm, REALM_SZ)) == 0)
return(AD_NOTGT);
else{
if ((kerror =
get_ad_tkt("krbtgt",realm,lrealm,lifetime)) != KSUCCESS)
return(kerror);
if ((kerror = krb_get_cred("krbtgt",realm,lrealm,&cr)) != KSUCCESS)
return(kerror);
}
}
/*
* Make up a request packet to the "krbtgt.realm@lrealm".
* Start by calling krb_mk_req() which puts ticket+authenticator
* into "pkt". Then tack other stuff on the end.
*/
kerror = krb_mk_req(pkt,"krbtgt",realm,lrealm,0L);
if (kerror)
return(AD_NOTGT);
/* timestamp */
bcopy((char *) &time_ws,(char *) (pkt->dat+pkt->length),4);
pkt->length += 4;
*(pkt->dat+(pkt->length)++) = (char) lifetime;
(void) strcpy((char *) (pkt->dat+pkt->length),service);
pkt->length += 1 + strlen(service);
(void) strcpy((char *)(pkt->dat+pkt->length),sinstance);
pkt->length += 1 + strlen(sinstance);
rpkt->length = 0;
/* Send the request to the local ticket-granting server */
if (kerror = send_to_kdc(pkt, rpkt, realm)) return(kerror);
/* check packet version of the returned packet */
if (pkt_version(rpkt) != KRB_PROT_VERSION )
return(INTK_PROT);
/* Check byte order */
msg_byte_order = pkt_msg_type(rpkt) & 1;
swap_bytes = 0;
if (msg_byte_order != HOST_BYTE_ORDER)
swap_bytes++;
switch (pkt_msg_type(rpkt) & ~1) {
case AUTH_MSG_KDC_REPLY:
break;
case AUTH_MSG_ERR_REPLY:
bcopy(pkt_err_code(rpkt), (char *) &rep_err_code, 4);
if (swap_bytes)
swap_u_long(rep_err_code);
return(rep_err_code);
default:
return(INTK_PROT);
}
/* Extract the ciphertext */
cip->length = pkt_clen(rpkt); /* let clen do the swap */
bcopy((char *) pkt_cipher(rpkt),(char *) (cip->dat),cip->length);
#ifndef NOENCRYPTION
key_sched(cr.session,key_s);
pcbc_encrypt((C_Block *)cip->dat,(C_Block *)cip->dat,(long)cip->length,
key_s,cr.session,DECRYPT);
#endif
/* Get rid of all traces of key */
bzero((char *) cr.session, sizeof(key));
bzero((char *) key_s, sizeof(key_s));
ptr = (char *) cip->dat;
bcopy(ptr,(char *)ses,8);
ptr += 8;
(void) strcpy(s_name,ptr);
ptr += strlen(s_name) + 1;
(void) strcpy(s_instance,ptr);
ptr += strlen(s_instance) + 1;
(void) strcpy(rlm,ptr);
ptr += strlen(rlm) + 1;
lifetime = (unsigned long) ptr[0];
kvno = (unsigned long) ptr[1];
tkt->length = (int) ptr[2];
ptr += 3;
bcopy(ptr,(char *)(tkt->dat),tkt->length);
ptr += tkt->length;
if (strcmp(s_name, service) || strcmp(s_instance, sinstance) ||
strcmp(rlm, realm)) /* not what we asked for */
return(INTK_ERR); /* we need a better code here XXX */
/* check KDC time stamp */
bcopy(ptr,(char *)&kdc_time,4); /* Time (coarse) */
if (swap_bytes) swap_u_long(kdc_time);
ptr += 4;
(void) gettimeofday(&tt_local,(struct timezone *) 0);
if (abs((int)(tt_local.tv_sec - kdc_time)) > CLOCK_SKEW) {
return(RD_AP_TIME); /* XXX should probably be better
code */
}
if (kerror = save_credentials(s_name,s_instance,rlm,ses,lifetime,
kvno,tkt,tt_local.tv_sec))
return(kerror);
return(AD_OK);
}