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/* -*- mode: c; indent-tabs-mode: nil -*- */
/* tests/gssapi/t_s4u2proxy_deleg.c - Test S4U2Proxy after krb5 auth */
/*
* Copyright 2011 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 <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "common.h"
/*
* Usage: ./t_s4u2proxy_krb5 [--spnego] client_cache storage_cache
* [accname|-] service1 service2
*
* This program performs a regular Kerberos or SPNEGO authentication from the
* default principal of client_cache to service1. If that authentication
* yields delegated credentials, the program stores those credentials in
* sorage_ccache and uses that cache to perform a second authentication to
* service2 using S4U2Proxy.
*
* The default keytab must contain keys for service1 and service2. The default
* ccache must contain a TGT for service1. This program assumes that krb5 or
* SPNEGO authentication requires only one token exchange.
*/
int
main(int argc, char *argv[])
{
const char *client_ccname, *storage_ccname, *accname, *service1, *service2;
krb5_context context = NULL;
krb5_error_code ret;
krb5_boolean use_spnego = FALSE;
krb5_ccache storage_ccache = NULL;
krb5_principal client_princ = NULL;
OM_uint32 minor, major, flags;
gss_buffer_desc buf = GSS_C_EMPTY_BUFFER;
gss_OID mech;
gss_OID_set mechs;
gss_name_t acceptor_name = GSS_C_NO_NAME, client_name = GSS_C_NO_NAME;
gss_name_t service1_name = GSS_C_NO_NAME, service2_name = GSS_C_NO_NAME;
gss_cred_id_t service1_cred = GSS_C_NO_CREDENTIAL;
gss_cred_id_t deleg_cred = GSS_C_NO_CREDENTIAL;
gss_ctx_id_t initiator_context, acceptor_context;
/* Parse arguments. */
if (argc >= 2 && strcmp(argv[1], "--spnego") == 0) {
use_spnego = TRUE;
argc--;
argv++;
}
if (argc != 6) {
fprintf(stderr, "./t_s4u2proxy_krb5 [--spnego] client_ccache "
"storage_ccache [accname|-] service1 service2\n");
return 1;
}
client_ccname = argv[1];
storage_ccname = argv[2];
accname = argv[3];
service1 = argv[4];
service2 = argv[5];
mech = use_spnego ? &mech_spnego : &mech_krb5;
mechs = use_spnego ? &mechset_spnego : &mechset_krb5;
ret = krb5_init_context(&context);
check_k5err(context, "krb5_init_context", ret);
/* Get GSS_C_BOTH acceptor credentials, using the default ccache. */
acceptor_name = GSS_C_NO_NAME;
if (strcmp(accname, "-") != 0)
acceptor_name = import_name(service1);
major = gss_acquire_cred(&minor, acceptor_name, GSS_C_INDEFINITE,
mechs, GSS_C_BOTH, &service1_cred, NULL, NULL);
check_gsserr("gss_acquire_cred(service1)", major, minor);
/* Establish contexts using the client ccache. */
service1_name = import_name(service1);
major = gss_krb5_ccache_name(&minor, client_ccname, NULL);
check_gsserr("gss_krb5_ccache_name(1)", major, minor);
flags = GSS_C_REPLAY_FLAG | GSS_C_SEQUENCE_FLAG;
establish_contexts(mech, GSS_C_NO_CREDENTIAL, service1_cred, service1_name,
flags, &initiator_context, &acceptor_context,
&client_name, NULL, &deleg_cred);
/* Display and remember the client principal. */
major = gss_display_name(&minor, client_name, &buf, NULL);
check_gsserr("gss_display_name(1)", major, minor);
printf("auth1: %.*s\n", (int)buf.length, (char *)buf.value);
/* Assumes buffer is null-terminated, which in our implementation it is. */
ret = krb5_parse_name(context, buf.value, &client_princ);
check_k5err(context, "krb5_parse_name", ret);
(void)gss_release_buffer(&minor, &buf);
if (deleg_cred == GSS_C_NO_CREDENTIAL) {
printf("no credential delegated.\n");
goto cleanup;
}
/* Take the opportunity to test cred export/import on the synthesized
* S4U2Proxy delegated cred. */
export_import_cred(&deleg_cred);
/* Store the delegated credentials. */
ret = krb5_cc_resolve(context, storage_ccname, &storage_ccache);
check_k5err(context, "krb5_cc_resolve", ret);
ret = krb5_cc_initialize(context, storage_ccache, client_princ);
check_k5err(context, "krb5_cc_initialize", ret);
major = gss_krb5_copy_ccache(&minor, deleg_cred, storage_ccache);
check_gsserr("gss_krb5_copy_ccache", major, minor);
ret = krb5_cc_close(context, storage_ccache);
check_k5err(context, "krb5_cc_close", ret);
(void)gss_delete_sec_context(&minor, &initiator_context, GSS_C_NO_BUFFER);
(void)gss_delete_sec_context(&minor, &acceptor_context, GSS_C_NO_BUFFER);
/* Establish contexts using the storage ccache. */
service2_name = import_name(service2);
major = gss_krb5_ccache_name(&minor, storage_ccname, NULL);
check_gsserr("gss_krb5_ccache_name(2)", major, minor);
establish_contexts(mech, GSS_C_NO_CREDENTIAL, GSS_C_NO_CREDENTIAL,
service2_name, flags, &initiator_context,
&acceptor_context, &client_name, NULL, &deleg_cred);
major = gss_display_name(&minor, client_name, &buf, NULL);
check_gsserr("gss_display_name(2)", major, minor);
printf("auth2: %.*s\n", (int)buf.length, (char *)buf.value);
(void)gss_release_buffer(&minor, &buf);
cleanup:
(void)gss_release_name(&minor, &acceptor_name);
(void)gss_release_name(&minor, &client_name);
(void)gss_release_name(&minor, &service1_name);
(void)gss_release_name(&minor, &service2_name);
(void)gss_release_cred(&minor, &service1_cred);
(void)gss_release_cred(&minor, &deleg_cred);
(void)gss_delete_sec_context(&minor, &initiator_context, GSS_C_NO_BUFFER);
(void)gss_delete_sec_context(&minor, &acceptor_context, GSS_C_NO_BUFFER);
krb5_free_principal(context, client_princ);
krb5_free_context(context);
return 0;
}
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