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/*
* lib/krb5/krb/gc_via_tgt.c
*
* Copyright 1990,1991 by the Massachusetts Institute of Technology.
* All Rights Reserved.
*
* Export of this software from the United States of America may
* 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.
*
*
* Given a tkt, and a target cred, get it.
* Assumes that the kdc_rep has been decrypted.
*/
#include "k5-int.h"
#include "int-proto.h"
#define in_clock_skew(date, now) (labs((date)-(now)) < context->clockskew)
static krb5_error_code
krb5_kdcrep2creds(context, pkdcrep, address, psectkt, ppcreds)
krb5_context context;
krb5_kdc_rep * pkdcrep;
krb5_address *const * address;
krb5_data * psectkt;
krb5_creds ** ppcreds;
{
krb5_error_code retval;
krb5_data *pdata;
if ((*ppcreds = (krb5_creds *)malloc(sizeof(krb5_creds))) == NULL) {
return ENOMEM;
}
memset(*ppcreds, 0, sizeof(krb5_creds));
if ((retval = krb5_copy_principal(context, pkdcrep->client,
&(*ppcreds)->client)))
goto cleanup;
if ((retval = krb5_copy_principal(context, pkdcrep->enc_part2->server,
&(*ppcreds)->server)))
goto cleanup;
if ((retval = krb5_copy_keyblock_contents(context,
pkdcrep->enc_part2->session,
&(*ppcreds)->keyblock)))
goto cleanup;
if ((retval = krb5_copy_data(context, psectkt, &pdata)))
goto cleanup;
(*ppcreds)->second_ticket = *pdata;
krb5_xfree(pdata);
(*ppcreds)->ticket_flags = pkdcrep->enc_part2->flags;
(*ppcreds)->times = pkdcrep->enc_part2->times;
(*ppcreds)->magic = KV5M_CREDS;
(*ppcreds)->authdata = NULL; /* not used */
(*ppcreds)->is_skey = psectkt->length != 0;
if (pkdcrep->enc_part2->caddrs) {
if ((retval = krb5_copy_addresses(context, pkdcrep->enc_part2->caddrs,
&(*ppcreds)->addresses)))
goto cleanup_keyblock;
} else {
/* no addresses in the list means we got what we had */
if ((retval = krb5_copy_addresses(context, address,
&(*ppcreds)->addresses)))
goto cleanup_keyblock;
}
if ((retval = encode_krb5_ticket(pkdcrep->ticket, &pdata)))
goto cleanup_keyblock;
(*ppcreds)->ticket = *pdata;
free(pdata);
return 0;
cleanup_keyblock:
krb5_free_keyblock(context, &(*ppcreds)->keyblock);
cleanup:
free (*ppcreds);
return retval;
}
krb5_error_code
krb5_get_cred_via_tkt (context, tkt, kdcoptions, address, in_cred, out_cred)
krb5_context context;
krb5_creds * tkt;
const krb5_flags kdcoptions;
krb5_address *const * address;
krb5_creds * in_cred;
krb5_creds ** out_cred;
{
krb5_error_code retval;
krb5_kdc_rep *dec_rep;
krb5_error *err_reply;
krb5_response tgsrep;
krb5_enctype *enctypes = 0;
/* tkt->client must be equal to in_cred->client */
if (!krb5_principal_compare(context, tkt->client, in_cred->client))
return KRB5_PRINC_NOMATCH;
if (!tkt->ticket.length)
return KRB5_NO_TKT_SUPPLIED;
if ((kdcoptions & KDC_OPT_ENC_TKT_IN_SKEY) &&
(!in_cred->second_ticket.length))
return(KRB5_NO_2ND_TKT);
/* check if we have the right TGT */
/* tkt->server must be equal to */
/* krbtgt/realmof(cred->server)@realmof(tgt->server) */
/*
{
krb5_principal tempprinc;
if (retval = krb5_tgtname(context,
krb5_princ_realm(context, in_cred->server),
krb5_princ_realm(context, tkt->server), &tempprinc))
return(retval);
if (!krb5_principal_compare(context, tempprinc, tkt->server)) {
krb5_free_principal(context, tempprinc);
return (KRB5_PRINC_NOMATCH);
}
krb5_free_principal(context, tempprinc);
}
*/
if (in_cred->keyblock.enctype) {
enctypes = (krb5_enctype *) malloc(sizeof(krb5_enctype)*2);
if (!enctypes)
return ENOMEM;
enctypes[0] = in_cred->keyblock.enctype;
enctypes[1] = 0;
}
retval = krb5_send_tgs(context, kdcoptions, &in_cred->times, enctypes,
in_cred->server, address, in_cred->authdata,
0, /* no padata */
(kdcoptions & KDC_OPT_ENC_TKT_IN_SKEY) ?
&in_cred->second_ticket : NULL,
tkt, &tgsrep);
if (enctypes)
free(enctypes);
if (retval)
return retval;
switch (tgsrep.message_type) {
case KRB5_TGS_REP:
break;
case KRB5_ERROR:
default:
if (krb5_is_krb_error(&tgsrep.response))
retval = decode_krb5_error(&tgsrep.response, &err_reply);
else
retval = KRB5KRB_AP_ERR_MSG_TYPE;
if (retval) /* neither proper reply nor error! */
goto error_4;
retval = err_reply->error + ERROR_TABLE_BASE_krb5;
krb5_free_error(context, err_reply);
goto error_4;
}
if ((retval = krb5_decode_kdc_rep(context, &tgsrep.response,
&tkt->keyblock, &dec_rep)))
goto error_4;
if (dec_rep->msg_type != KRB5_TGS_REP) {
retval = KRB5KRB_AP_ERR_MSG_TYPE;
goto error_3;
}
/* make sure the response hasn't been tampered with..... */
retval = 0;
if (!krb5_principal_compare(context, dec_rep->client, tkt->client))
retval = KRB5_KDCREP_MODIFIED;
if (!krb5_principal_compare(context, dec_rep->enc_part2->server, in_cred->server))
retval = KRB5_KDCREP_MODIFIED;
if (!krb5_principal_compare(context, dec_rep->ticket->server, in_cred->server))
retval = KRB5_KDCREP_MODIFIED;
if (dec_rep->enc_part2->nonce != tgsrep.expected_nonce)
retval = KRB5_KDCREP_MODIFIED;
if ((kdcoptions & KDC_OPT_POSTDATED) &&
(in_cred->times.starttime != 0) &&
(in_cred->times.starttime != dec_rep->enc_part2->times.starttime))
retval = KRB5_KDCREP_MODIFIED;
if ((in_cred->times.endtime != 0) &&
(dec_rep->enc_part2->times.endtime > in_cred->times.endtime))
retval = KRB5_KDCREP_MODIFIED;
if ((kdcoptions & KDC_OPT_RENEWABLE) &&
(in_cred->times.renew_till != 0) &&
(dec_rep->enc_part2->times.renew_till > in_cred->times.renew_till))
retval = KRB5_KDCREP_MODIFIED;
if ((kdcoptions & KDC_OPT_RENEWABLE_OK) &&
(dec_rep->enc_part2->flags & KDC_OPT_RENEWABLE) &&
(in_cred->times.endtime != 0) &&
(dec_rep->enc_part2->times.renew_till > in_cred->times.endtime))
retval = KRB5_KDCREP_MODIFIED;
if (retval != 0)
goto error_3;
if (!in_cred->times.starttime &&
!in_clock_skew(dec_rep->enc_part2->times.starttime,
tgsrep.request_time)) {
retval = KRB5_KDCREP_SKEW;
goto error_3;
}
retval = krb5_kdcrep2creds(context, dec_rep, address,
&in_cred->second_ticket, out_cred);
error_3:;
memset(dec_rep->enc_part2->session->contents, 0,
dec_rep->enc_part2->session->length);
krb5_free_kdc_rep(context, dec_rep);
error_4:;
free(tgsrep.response.data);
return retval;
}
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