/*      $NetBSD: accessors.c,v 1.3 2016/01/26 23:12:17 pooka Exp $      */

/*
 * Copyright (c) 2007-2011 Antti Kantee.  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 ``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.
 */

/*
 * This file contains various data structure accessor routines.
 * They are meant to help clients that make calls into the depths
 * of the kernel (e.g. at vfs layer) bypassing the syscall layer.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: accessors.c,v 1.3 2016/01/26 23:12:17 pooka Exp $");

#include <sys/param.h>
#include <sys/kauth.h>
#include <sys/kmem.h>
#include <sys/uio.h>

#include <rump-sys/kern.h>

struct uio *
rump_uio_setup(void *buf, size_t bufsize, off_t offset, enum rump_uiorw rw)
{
        struct uio *uio;
        enum uio_rw uiorw;

        switch (rw) {
        case RUMPUIO_READ:
                uiorw = UIO_READ;
                break;
        case RUMPUIO_WRITE:
                uiorw = UIO_WRITE;
                break;
        default:
                panic("%s: invalid rw %d", __func__, rw);
        }

        uio = kmem_alloc(sizeof(struct uio), KM_SLEEP);
        uio->uio_iov = kmem_alloc(sizeof(struct iovec), KM_SLEEP);

        uio->uio_iov->iov_base = buf;
        uio->uio_iov->iov_len = bufsize;

        uio->uio_iovcnt = 1;
        uio->uio_offset = offset;
        uio->uio_resid = bufsize;
        uio->uio_rw = uiorw;
        uio->uio_vmspace = curproc->p_vmspace;

        return uio;
}

size_t
rump_uio_getresid(struct uio *uio)
{

        return uio->uio_resid;
}

off_t
rump_uio_getoff(struct uio *uio)
{

        return uio->uio_offset;
}

size_t
rump_uio_free(struct uio *uio)
{
        size_t resid;

        resid = uio->uio_resid;
        kmem_free(uio->uio_iov, sizeof(*uio->uio_iov));
        kmem_free(uio, sizeof(*uio));

        return resid;
}

kauth_cred_t
rump_cred_create(uid_t uid, gid_t gid, size_t ngroups, gid_t *groups)
{
        kauth_cred_t cred;
        int rv;

        cred = kauth_cred_alloc();
        kauth_cred_setuid(cred, uid);
        kauth_cred_seteuid(cred, uid);
        kauth_cred_setsvuid(cred, uid);
        kauth_cred_setgid(cred, gid);
        kauth_cred_setgid(cred, gid);
        kauth_cred_setegid(cred, gid);
        kauth_cred_setsvgid(cred, gid);
        rv = kauth_cred_setgroups(cred, groups, ngroups, 0, UIO_SYSSPACE);
        /* oh this is silly.  and by "this" I mean kauth_cred_setgroups() */
        assert(rv == 0);

        return cred;
}

void
rump_cred_put(kauth_cred_t cred)
{

        kauth_cred_free(cred);
}