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/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
* Copyright 2010 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 <assert.h>
#include "common.h"
static gss_OID_desc mech_krb5_wrong = {
9, "\052\206\110\202\367\022\001\002\002"
};
gss_OID_set_desc mechset_krb5_wrong = { 1, &mech_krb5_wrong };
/*
* Test program for SPNEGO and gss_set_neg_mechs
*
* Example usage:
*
* kinit testuser
* ./t_spnego host/test.host@REALM testhost.keytab
*/
int
main(int argc, char *argv[])
{
OM_uint32 minor, major, flags;
gss_cred_id_t verifier_cred_handle = GSS_C_NO_CREDENTIAL;
gss_cred_id_t initiator_cred_handle = GSS_C_NO_CREDENTIAL;
gss_OID_set actual_mechs = GSS_C_NO_OID_SET;
gss_buffer_desc itok = GSS_C_EMPTY_BUFFER, atok = GSS_C_EMPTY_BUFFER;
gss_ctx_id_t initiator_context, acceptor_context;
gss_name_t target_name, source_name = GSS_C_NO_NAME;
gss_OID mech = GSS_C_NO_OID;
const unsigned char *atok_oid;
if (argc < 2 || argc > 3) {
fprintf(stderr, "Usage: %s target_name [keytab]\n", argv[0]);
exit(1);
}
target_name = import_name(argv[1]);
if (argc >= 3) {
major = krb5_gss_register_acceptor_identity(argv[2]);
check_gsserr("krb5_gss_register_acceptor_identity", major, 0);
}
/* Get default acceptor cred. */
major = gss_acquire_cred(&minor, GSS_C_NO_NAME, GSS_C_INDEFINITE,
&mechset_spnego, GSS_C_ACCEPT,
&verifier_cred_handle, &actual_mechs, NULL);
check_gsserr("gss_acquire_cred", major, minor);
/* Restrict the acceptor to krb5, to exercise the neg_mechs logic. */
major = gss_set_neg_mechs(&minor, verifier_cred_handle, &mechset_krb5);
check_gsserr("gss_set_neg_mechs", major, minor);
flags = GSS_C_REPLAY_FLAG | GSS_C_SEQUENCE_FLAG;
establish_contexts(&mech_spnego, GSS_C_NO_CREDENTIAL, verifier_cred_handle,
target_name, flags, &initiator_context,
&acceptor_context, &source_name, &mech, NULL);
display_canon_name("Source name", source_name, &mech_krb5);
display_oid("Source mech", mech);
(void)gss_delete_sec_context(&minor, &initiator_context, NULL);
(void)gss_delete_sec_context(&minor, &acceptor_context, NULL);
(void)gss_release_name(&minor, &source_name);
(void)gss_release_cred(&minor, &verifier_cred_handle);
(void)gss_release_oid_set(&minor, &actual_mechs);
/*
* Test that the SPNEGO acceptor code properly reflects back the erroneous
* Microsoft mech OID in the supportedMech field of the NegTokenResp
* message. Our initiator code doesn't care (it treats all variants of the
* krb5 mech as equivalent when comparing the supportedMech response to its
* first-choice mech), so we have to look directly at the DER encoding of
* the response token. If we don't request mutual authentication, the
* SPNEGO reply will contain no underlying mech token, so the encoding of
* the correct NegotiationToken response is completely predictable:
*
* A1 14 (choice 1, length 20, meaning negTokenResp)
* 30 12 (sequence, length 18)
* A0 03 (context tag 0, length 3)
* 0A 01 00 (enumerated value 0, meaning accept-completed)
* A1 0B (context tag 1, length 11)
* 06 09 (object identifier, length 9)
* 2A 86 48 82 F7 12 01 02 02 (the erroneous krb5 OID)
*
* So we can just compare the length to 22 and the nine bytes at offset 13
* to the expected OID.
*/
major = gss_acquire_cred(&minor, GSS_C_NO_NAME, GSS_C_INDEFINITE,
&mechset_spnego, GSS_C_INITIATE,
&initiator_cred_handle, NULL, NULL);
check_gsserr("gss_acquire_cred(2)", major, minor);
major = gss_set_neg_mechs(&minor, initiator_cred_handle,
&mechset_krb5_wrong);
check_gsserr("gss_set_neg_mechs(2)", major, minor);
major = gss_init_sec_context(&minor, initiator_cred_handle,
&initiator_context, target_name, &mech_spnego,
flags, GSS_C_INDEFINITE,
GSS_C_NO_CHANNEL_BINDINGS, &atok, NULL, &itok,
NULL, NULL);
check_gsserr("gss_init_sec_context", major, minor);
assert(major == GSS_S_CONTINUE_NEEDED);
major = gss_accept_sec_context(&minor, &acceptor_context,
GSS_C_NO_CREDENTIAL, &itok,
GSS_C_NO_CHANNEL_BINDINGS, NULL,
NULL, &atok, NULL, NULL, NULL);
assert(atok.length == 22);
atok_oid = (unsigned char *)atok.value + 13;
assert(memcmp(atok_oid, mech_krb5_wrong.elements, 9) == 0);
check_gsserr("gss_accept_sec_context", major, minor);
(void)gss_delete_sec_context(&minor, &initiator_context, NULL);
(void)gss_delete_sec_context(&minor, &acceptor_context, NULL);
(void)gss_release_cred(&minor, &initiator_cred_handle);
(void)gss_release_name(&minor, &target_name);
(void)gss_release_buffer(&minor, &itok);
(void)gss_release_buffer(&minor, &atok);
return 0;
}
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