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/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/* lib/krb5/krb/fwd_tgt.c Definition of krb5_fwd_tgt_creds() routine */
/*
* Copyright 1995 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. Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
* 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 "k5-int.h"
#ifdef HAVE_MEMORY_H
#include <memory.h>
#endif
#include "int-proto.h"
#include "os-proto.h"
/* helper function: convert flags to necessary KDC options */
#define flags2options(flags) (flags & KDC_TKT_COMMON_MASK)
/* Get a TGT for use at the remote host */
krb5_error_code KRB5_CALLCONV
krb5_fwd_tgt_creds(krb5_context context, krb5_auth_context auth_context,
char *rhost, krb5_principal client, krb5_principal server,
krb5_ccache cc, int forwardable, krb5_data *outbuf)
/* Should forwarded TGT also be forwardable? */
{
krb5_replay_data replaydata;
krb5_data * scratch = 0;
krb5_address **addrs = NULL;
krb5_error_code retval;
krb5_creds creds, tgt;
krb5_creds *pcreds;
krb5_flags kdcoptions;
int close_cc = 0;
int free_rhost = 0;
krb5_enctype enctype = 0;
krb5_keyblock *session_key;
krb5_boolean old_use_conf_ktypes = context->use_conf_ktypes;
memset(&creds, 0, sizeof(creds));
memset(&tgt, 0, sizeof(creds));
if (cc == 0) {
if ((retval = krb5int_cc_default(context, &cc)))
goto errout;
close_cc = 1;
}
retval = krb5_auth_con_getkey (context, auth_context, &session_key);
if (retval)
goto errout;
if (session_key) {
enctype = session_key->enctype;
krb5_free_keyblock (context, session_key);
session_key = NULL;
} else if (server) { /* must server be non-NULL when rhost is given? */
/* Try getting credentials to see what the remote side supports.
Not bulletproof, just a heuristic. */
krb5_creds in, *out = 0;
memset (&in, 0, sizeof(in));
retval = krb5_copy_principal (context, server, &in.server);
if (retval)
goto punt;
retval = krb5_copy_principal (context, client, &in.client);
if (retval)
goto punt;
retval = krb5_get_credentials (context, 0, cc, &in, &out);
if (retval)
goto punt;
/* Got the credentials. Okay, now record the enctype and
throw them away. */
enctype = out->keyblock.enctype;
krb5_free_creds (context, out);
punt:
krb5_free_cred_contents (context, &in);
}
if ((retval = krb5_copy_principal(context, client, &creds.client)))
goto errout;
retval = krb5int_tgtname(context, &client->realm, &client->realm,
&creds.server);
if (retval)
goto errout;
/* fetch tgt directly from cache */
context->use_conf_ktypes = 1;
retval = krb5_cc_retrieve_cred (context, cc, KRB5_TC_SUPPORTED_KTYPES,
&creds, &tgt);
context->use_conf_ktypes = old_use_conf_ktypes;
if (retval)
goto errout;
/* tgt->client must be equal to creds.client */
if (!krb5_principal_compare(context, tgt.client, creds.client)) {
retval = KRB5_PRINC_NOMATCH;
goto errout;
}
if (!tgt.ticket.length) {
retval = KRB5_NO_TKT_SUPPLIED;
goto errout;
}
if (tgt.addresses && *tgt.addresses) {
if (rhost == NULL) {
if (krb5_princ_type(context, server) != KRB5_NT_SRV_HST) {
retval = KRB5_FWD_BAD_PRINCIPAL;
goto errout;
}
if (krb5_princ_size(context, server) < 2){
retval = KRB5_CC_BADNAME;
goto errout;
}
rhost = k5memdup0(server->data[1].data, server->data[1].length,
&retval);
if (rhost == NULL)
goto errout;
free_rhost = 1;
}
retval = k5_os_hostaddr(context, rhost, &addrs);
if (retval)
goto errout;
}
creds.keyblock.enctype = enctype;
creds.times = tgt.times;
creds.times.starttime = 0;
kdcoptions = flags2options(tgt.ticket_flags)|KDC_OPT_FORWARDED;
if (!forwardable) /* Reset KDC_OPT_FORWARDABLE */
kdcoptions &= ~(KDC_OPT_FORWARDABLE);
if ((retval = krb5_get_cred_via_tkt(context, &tgt, kdcoptions,
addrs, &creds, &pcreds))) {
if (enctype) {
creds.keyblock.enctype = 0;
if ((retval = krb5_get_cred_via_tkt(context, &tgt, kdcoptions,
addrs, &creds, &pcreds)))
goto errout;
}
else goto errout;
}
retval = krb5_mk_1cred(context, auth_context, pcreds,
&scratch, &replaydata);
krb5_free_creds(context, pcreds);
if (retval) {
if (scratch)
krb5_free_data(context, scratch);
} else {
*outbuf = *scratch;
free(scratch);
}
errout:
if (addrs)
krb5_free_addresses(context, addrs);
if (close_cc)
krb5_cc_close(context, cc);
if (free_rhost)
free(rhost);
krb5_free_cred_contents(context, &creds);
krb5_free_cred_contents(context, &tgt);
return retval;
}
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