/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2005 Doug Rabson
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <gssapi/gssapi.h>
#include <stdlib.h>
#include <errno.h>

#include "mech_switch.h"
#include "name.h"
#include "cred.h"

OM_uint32
gss_acquire_cred(OM_uint32 *minor_status,
    const gss_name_t desired_name,
    OM_uint32 time_req,
    const gss_OID_set desired_mechs,
    gss_cred_usage_t cred_usage,
    gss_cred_id_t *output_cred_handle,
    gss_OID_set *actual_mechs,
    OM_uint32 *time_rec)
{
        OM_uint32 major_status;
        gss_OID_set mechs = desired_mechs;
        gss_OID_set_desc set;
        struct _gss_name *name = (struct _gss_name *) desired_name;
        struct _gss_mech_switch *m;
        struct _gss_cred *cred;
        struct _gss_mechanism_cred *mc;
        struct _gss_mechanism_name *mn;
        OM_uint32 min_time, cred_time;
        size_t i;

        *minor_status = 0;
        if (output_cred_handle)
                *output_cred_handle = GSS_C_NO_CREDENTIAL;
        if (actual_mechs)
                *actual_mechs = GSS_C_NO_OID_SET;
        if (time_rec)
                *time_rec = 0;

        _gss_load_mech();

        /*
         * First make sure that at least one of the requested
         * mechanisms is one that we support.
         */
        if (mechs) {
                for (i = 0; i < mechs->count; i++) {
                        int t;
                        gss_test_oid_set_member(minor_status,
                            &mechs->elements[i], _gss_mech_oids, &t);
                        if (t)
                                break;
                }
                if (i == mechs->count) {
                        *minor_status = 0;
                        return (GSS_S_BAD_MECH);
                }
        } else {
                mechs = _gss_mech_oids;
        }

        if (actual_mechs) {
                major_status = gss_create_empty_oid_set(minor_status,
                    actual_mechs);
                if (major_status)
                        return (major_status);
        }

        cred = malloc(sizeof(struct _gss_cred));
        if (!cred) {
                if (actual_mechs)
                        gss_release_oid_set(minor_status, actual_mechs);
                *minor_status = ENOMEM;
                return (GSS_S_FAILURE);
        }
        SLIST_INIT(&cred->gc_mc);

        set.count = 1;
        min_time = GSS_C_INDEFINITE;
        for (i = 0; i < mechs->count; i++) {
                m = _gss_find_mech_switch(&mechs->elements[i]);
                if (!m)
                        continue;

                if (desired_name != GSS_C_NO_NAME) {
                        major_status = _gss_find_mn(minor_status, name,
                                                    &mechs->elements[i], &mn);
                        if (major_status != GSS_S_COMPLETE)
                                continue;
                }

                mc = malloc(sizeof(struct _gss_mechanism_cred));
                if (!mc) {
                        continue;
                }
                mc->gmc_mech = m;
                mc->gmc_mech_oid = &m->gm_mech_oid;

                /*
                 * XXX Probably need to do something with actual_mechs.
                 */
                set.elements = &mechs->elements[i];
                major_status = m->gm_acquire_cred(minor_status,
                    (desired_name != GSS_C_NO_NAME
                        ? mn->gmn_name : GSS_C_NO_NAME),
                    time_req, &set, cred_usage,
                    &mc->gmc_cred, NULL, &cred_time);
                if (major_status) {
                        free(mc);
                        continue;
                }
                if (cred_time < min_time)
                        min_time = cred_time;

                if (actual_mechs) {
                        major_status = gss_add_oid_set_member(minor_status,
                            mc->gmc_mech_oid, actual_mechs);
                        if (major_status) {
                                m->gm_release_cred(minor_status,
                                    &mc->gmc_cred);
                                free(mc);
                                continue;
                        }
                }

                SLIST_INSERT_HEAD(&cred->gc_mc, mc, gmc_link);
        }

        /*
         * If we didn't manage to create a single credential, return
         * an error.
         */
        if (!SLIST_FIRST(&cred->gc_mc)) {
                free(cred);
                if (actual_mechs)
                        gss_release_oid_set(minor_status, actual_mechs);
                *minor_status = 0;
                return (GSS_S_NO_CRED);
        }

        if (time_rec)
                *time_rec = min_time;
        *output_cred_handle = (gss_cred_id_t) cred;
        *minor_status = 0;
        return (GSS_S_COMPLETE);
}