/*
 * Copyright (c) 2003-2004 Kungliga Tekniska Högskolan
 * (Royal Institute of Technology, Stockholm, Sweden).
 * 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.
 *
 * 3. Neither the name of KTH nor the names of its contributors may be
 *    used to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY KTH AND ITS 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 KTH OR ITS 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.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <roken.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <gssapi.h>
#include <gssapi_krb5.h>
#include <gssapi_spnego.h>
#include <err.h>
#include <getarg.h>

static void
gss_print_errors (int min_stat)
{
    OM_uint32 new_stat;
    OM_uint32 msg_ctx = 0;
    gss_buffer_desc status_string;
    OM_uint32 ret;

    do {
        ret = gss_display_status (&new_stat,
                                  min_stat,
                                  GSS_C_MECH_CODE,
                                  GSS_C_NO_OID,
                                  &msg_ctx,
                                  &status_string);
        if (!GSS_ERROR(ret)) {
            fprintf (stderr, "%.*s\n", (int)status_string.length,
                                        (char *)status_string.value);
            gss_release_buffer (&new_stat, &status_string);
        }
    } while (!GSS_ERROR(ret) && msg_ctx != 0);
}

static void
gss_err(int exitval, int status, const char *fmt, ...)
{
    va_list args;

    va_start(args, fmt);
    vwarnx (fmt, args);
    gss_print_errors (status);
    va_end(args);
    exit (exitval);
}

static void
acquire_release_loop(gss_name_t name, int counter, gss_cred_usage_t usage)
{
    OM_uint32 maj_stat, min_stat;
    gss_cred_id_t cred;
    int i;

    for (i = 0; i < counter; i++) {
        maj_stat = gss_acquire_cred(&min_stat, name,
                                    GSS_C_INDEFINITE,
                                    GSS_C_NO_OID_SET,
                                    usage,
                                    &cred,
                                    NULL,
                                    NULL);
        if (maj_stat != GSS_S_COMPLETE)
            gss_err(1, min_stat, "aquire %d %d != GSS_S_COMPLETE",
                    i, (int)maj_stat);

        maj_stat = gss_release_cred(&min_stat, &cred);
        if (maj_stat != GSS_S_COMPLETE)
            gss_err(1, min_stat, "release %d %d != GSS_S_COMPLETE",
                    i, (int)maj_stat);
    }
}


static void
acquire_add_release_add(gss_name_t name, gss_cred_usage_t usage)
{
    OM_uint32 maj_stat, min_stat;
    gss_cred_id_t cred, cred2, cred3;

    maj_stat = gss_acquire_cred(&min_stat, name,
                                GSS_C_INDEFINITE,
                                GSS_C_NO_OID_SET,
                                usage,
                                &cred,
                                NULL,
                                NULL);
    if (maj_stat != GSS_S_COMPLETE)
        gss_err(1, min_stat, "aquire %d != GSS_S_COMPLETE", (int)maj_stat);

    maj_stat = gss_add_cred(&min_stat,
                            cred,
                            GSS_C_NO_NAME,
                            GSS_KRB5_MECHANISM,
                            usage,
                            GSS_C_INDEFINITE,
                            GSS_C_INDEFINITE,
                            &cred2,
                            NULL,
                            NULL,
                            NULL);

    if (maj_stat != GSS_S_COMPLETE)
        gss_err(1, min_stat, "add_cred %d != GSS_S_COMPLETE", (int)maj_stat);

    maj_stat = gss_release_cred(&min_stat, &cred);
    if (maj_stat != GSS_S_COMPLETE)
        gss_err(1, min_stat, "release %d != GSS_S_COMPLETE", (int)maj_stat);

    maj_stat = gss_add_cred(&min_stat,
                            cred2,
                            GSS_C_NO_NAME,
                            GSS_KRB5_MECHANISM,
                            GSS_C_BOTH,
                            GSS_C_INDEFINITE,
                            GSS_C_INDEFINITE,
                            &cred3,
                            NULL,
                            NULL,
                            NULL);

    maj_stat = gss_release_cred(&min_stat, &cred2);
    if (maj_stat != GSS_S_COMPLETE)
        gss_err(1, min_stat, "release 2 %d != GSS_S_COMPLETE", (int)maj_stat);

    maj_stat = gss_release_cred(&min_stat, &cred3);
    if (maj_stat != GSS_S_COMPLETE)
        gss_err(1, min_stat, "release 2 %d != GSS_S_COMPLETE", (int)maj_stat);
}

static int version_flag = 0;
static int help_flag    = 0;

static struct getargs args[] = {
    {"version", 0,      arg_flag,       &version_flag, "print version", NULL },
    {"help",    0,      arg_flag,       &help_flag,  NULL, NULL }
};

static void
usage (int ret)
{
    arg_printusage (args, sizeof(args)/sizeof(*args),
                    NULL, "service@host");
    exit (ret);
}


int
main(int argc, char **argv)
{
    struct gss_buffer_desc_struct name_buffer;
    OM_uint32 maj_stat, min_stat;
    gss_name_t name;
    int optidx = 0;

    setprogname(argv[0]);
    if(getarg(args, sizeof(args) / sizeof(args[0]), argc, argv, &optidx))
        usage(1);

    if (help_flag)
        usage (0);

    if(version_flag){
        print_version(NULL);
        exit(0);
    }

    argc -= optidx;
    argv += optidx;

    if (argc < 1)
        errx(1, "argc < 1");

    name_buffer.value = argv[0];
    name_buffer.length = strlen(argv[0]);

    maj_stat = gss_import_name(&min_stat, &name_buffer,
                               GSS_C_NT_HOSTBASED_SERVICE,
                               &name);
    if (maj_stat != GSS_S_COMPLETE)
        errx(1, "import name error");

    acquire_release_loop(name, 100, GSS_C_ACCEPT);
    acquire_release_loop(name, 100, GSS_C_INITIATE);
    acquire_release_loop(name, 100, GSS_C_BOTH);

    acquire_add_release_add(name, GSS_C_ACCEPT);
    acquire_add_release_add(name, GSS_C_INITIATE);
    acquire_add_release_add(name, GSS_C_BOTH);

    gss_release_name(&min_stat, &name);

    return 0;
}