/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2000-2001 Boris Popov
 * 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 <sys/param.h>
#include <sys/kernel.h>
#include <sys/capsicum.h>
#include <sys/module.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/ioccom.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/file.h>           /* Must come after sys/malloc.h */
#include <sys/filedesc.h>
#include <sys/mbuf.h>
#include <sys/poll.h>
#include <sys/proc.h>
#include <sys/select.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sysctl.h>
#include <sys/uio.h>
#include <sys/vnode.h>

#include <net/if.h>

#include <netsmb/smb.h>
#include <netsmb/smb_conn.h>
#include <netsmb/smb_subr.h>
#include <netsmb/smb_dev.h>

static struct cdev *nsmb_dev;

static d_open_t  nsmb_dev_open;
static d_ioctl_t nsmb_dev_ioctl;

MODULE_DEPEND(netsmb, libiconv, 1, 1, 2);
MODULE_VERSION(netsmb, NSMB_VERSION);

static int smb_version = NSMB_VERSION;
struct sx smb_lock;

SYSCTL_DECL(_net_smb);
SYSCTL_INT(_net_smb, OID_AUTO, version, CTLFLAG_RD, &smb_version, 0, "");

static MALLOC_DEFINE(M_NSMBDEV, "NETSMBDEV", "NET/SMB device");

static struct cdevsw nsmb_cdevsw = {
        .d_version =    D_VERSION,
        .d_open =       nsmb_dev_open,
        .d_ioctl =      nsmb_dev_ioctl,
        .d_name =       NSMB_NAME
};

static int
nsmb_dev_init(void)
{

        nsmb_dev = make_dev(&nsmb_cdevsw, 0, UID_ROOT, GID_OPERATOR,
            0600, "nsmb");
        if (nsmb_dev == NULL)
                return (ENOMEM);  
        return (0);
}

static void 
nsmb_dev_destroy(void)
{

        MPASS(nsmb_dev != NULL);
        destroy_dev(nsmb_dev);
        nsmb_dev = NULL;
}

static struct smb_dev *
smbdev_alloc(struct cdev *dev)
{
        struct smb_dev *sdp;

        sdp = malloc(sizeof(struct smb_dev), M_NSMBDEV, M_WAITOK | M_ZERO);
        sdp->dev = dev; 
        sdp->sd_level = -1;
        sdp->sd_flags |= NSMBFL_OPEN;
        sdp->refcount = 1;
        return (sdp);   
} 

void
sdp_dtor(void *arg)
{
        struct smb_dev *dev;

        dev = (struct smb_dev *)arg;    
        SMB_LOCK();
        sdp_trydestroy(dev);
        SMB_UNLOCK();
}

static int
nsmb_dev_open(struct cdev *dev, int oflags, int devtype, struct thread *td)
{
        struct smb_dev *sdp;
        int error;

        sdp = smbdev_alloc(dev);
        error = devfs_set_cdevpriv(sdp, sdp_dtor);
        if (error) {
                free(sdp, M_NSMBDEV);   
                return (error);
        }
        return (0);
}

void
sdp_trydestroy(struct smb_dev *sdp)
{
        struct smb_vc *vcp;
        struct smb_share *ssp;
        struct smb_cred *scred;

        SMB_LOCKASSERT();
        if (!sdp)
                panic("No smb_dev upon device close");
        MPASS(sdp->refcount > 0);
        sdp->refcount--;
        if (sdp->refcount) 
                return;
        scred = malloc(sizeof(struct smb_cred), M_NSMBDEV, M_WAITOK);
        smb_makescred(scred, curthread, NULL);
        ssp = sdp->sd_share;
        if (ssp != NULL) {
                smb_share_lock(ssp);
                smb_share_rele(ssp, scred);
        }
        vcp = sdp->sd_vc;
        if (vcp != NULL) {
                smb_vc_lock(vcp);
                smb_vc_rele(vcp, scred);
        }
        free(scred, M_NSMBDEV);
        free(sdp, M_NSMBDEV);
        return;
}

static int
nsmb_dev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int flag, struct thread *td)
{
        struct smb_dev *sdp;
        struct smb_vc *vcp;
        struct smb_share *ssp;
        struct smb_cred *scred;
        int error = 0;

        error = devfs_get_cdevpriv((void **)&sdp);
        if (error)
                return (error);
        scred = malloc(sizeof(struct smb_cred), M_NSMBDEV, M_WAITOK);
        SMB_LOCK();
        smb_makescred(scred, td, NULL);
        switch (cmd) {
            case SMBIOC_OPENSESSION:
                if (sdp->sd_vc) {
                        error = EISCONN;
                        goto out;
                }
                error = smb_usr_opensession((struct smbioc_ossn*)data,
                    scred, &vcp);
                if (error)
                        break;
                sdp->sd_vc = vcp;
                smb_vc_unlock(vcp);
                sdp->sd_level = SMBL_VC;
                break;
            case SMBIOC_OPENSHARE:
                if (sdp->sd_share) {
                        error = EISCONN;
                        goto out;
                }
                if (sdp->sd_vc == NULL) {
                        error = ENOTCONN;
                        goto out;
                }
                error = smb_usr_openshare(sdp->sd_vc,
                    (struct smbioc_oshare*)data, scred, &ssp);
                if (error)
                        break;
                sdp->sd_share = ssp;
                smb_share_unlock(ssp);
                sdp->sd_level = SMBL_SHARE;
                break;
            case SMBIOC_REQUEST:
                if (sdp->sd_share == NULL) {
                        error = ENOTCONN;
                        goto out;
                }
                error = smb_usr_simplerequest(sdp->sd_share,
                    (struct smbioc_rq*)data, scred);
                break;
            case SMBIOC_T2RQ:
                if (sdp->sd_share == NULL) {
                        error = ENOTCONN;
                        goto out;
                }
                error = smb_usr_t2request(sdp->sd_share,
                    (struct smbioc_t2rq*)data, scred);
                break;
            case SMBIOC_SETFLAGS: {
                struct smbioc_flags *fl = (struct smbioc_flags*)data;
                int on;

                if (fl->ioc_level == SMBL_VC) {
                        if (fl->ioc_mask & SMBV_PERMANENT) {
                                on = fl->ioc_flags & SMBV_PERMANENT;
                                if ((vcp = sdp->sd_vc) == NULL) {
                                        error = ENOTCONN;
                                        goto out;
                                }
                                error = smb_vc_get(vcp, scred);
                                if (error)
                                        break;
                                if (on && (vcp->obj.co_flags & SMBV_PERMANENT) == 0) {
                                        vcp->obj.co_flags |= SMBV_PERMANENT;
                                        smb_vc_ref(vcp);
                                } else if (!on && (vcp->obj.co_flags & SMBV_PERMANENT)) {
                                        vcp->obj.co_flags &= ~SMBV_PERMANENT;
                                        smb_vc_rele(vcp, scred);
                                }
                                smb_vc_put(vcp, scred);
                        } else
                                error = EINVAL;
                } else if (fl->ioc_level == SMBL_SHARE) {
                        if (fl->ioc_mask & SMBS_PERMANENT) {
                                on = fl->ioc_flags & SMBS_PERMANENT;
                                if ((ssp = sdp->sd_share) == NULL) {
                                        error = ENOTCONN;
                                        goto out;
                                }
                                error = smb_share_get(ssp, scred);
                                if (error)
                                        break;
                                if (on && (ssp->obj.co_flags & SMBS_PERMANENT) == 0) {
                                        ssp->obj.co_flags |= SMBS_PERMANENT;
                                        smb_share_ref(ssp);
                                } else if (!on && (ssp->obj.co_flags & SMBS_PERMANENT)) {
                                        ssp->obj.co_flags &= ~SMBS_PERMANENT;
                                        smb_share_rele(ssp, scred);
                                }
                                smb_share_put(ssp, scred);
                        } else
                                error = EINVAL;
                        break;
                } else
                        error = EINVAL;
                break;
            }
            case SMBIOC_LOOKUP:
                if (sdp->sd_vc || sdp->sd_share) {
                        error = EISCONN;
                        goto out;
                }
                vcp = NULL;
                ssp = NULL;
                error = smb_usr_lookup((struct smbioc_lookup*)data, scred, &vcp, &ssp);
                if (error)
                        break;
                if (vcp) {
                        sdp->sd_vc = vcp;
                        smb_vc_unlock(vcp);
                        sdp->sd_level = SMBL_VC;
                }
                if (ssp) {
                        sdp->sd_share = ssp;
                        smb_share_unlock(ssp);
                        sdp->sd_level = SMBL_SHARE;
                }
                break;
            case SMBIOC_READ: case SMBIOC_WRITE: {
                struct smbioc_rw *rwrq = (struct smbioc_rw*)data;
                struct uio auio;
                struct iovec iov;

                if ((ssp = sdp->sd_share) == NULL) {
                        error = ENOTCONN;
                        goto out;
                }
                iov.iov_base = rwrq->ioc_base;
                iov.iov_len = rwrq->ioc_cnt;
                auio.uio_iov = &iov;
                auio.uio_iovcnt = 1;
                auio.uio_offset = rwrq->ioc_offset;
                auio.uio_resid = rwrq->ioc_cnt;
                auio.uio_segflg = UIO_USERSPACE;
                auio.uio_rw = (cmd == SMBIOC_READ) ? UIO_READ : UIO_WRITE;
                auio.uio_td = td;
                if (cmd == SMBIOC_READ)
                        error = smb_read(ssp, rwrq->ioc_fh, &auio, scred);
                else
                        error = smb_write(ssp, rwrq->ioc_fh, &auio, scred);
                rwrq->ioc_cnt -= auio.uio_resid;
                break;
            }
            default:
                error = ENODEV;
        }
out:
        free(scred, M_NSMBDEV);
        SMB_UNLOCK();
        return error;
}

static int
nsmb_dev_load(module_t mod, int cmd, void *arg)
{
        int error = 0;

        switch (cmd) {
            case MOD_LOAD:
                error = smb_sm_init();
                if (error)
                        break;
                error = smb_iod_init();
                if (error) {
                        smb_sm_done();
                        break;
                }
                error = nsmb_dev_init();
                if (error)
                        break;
                sx_init(&smb_lock, "samba device lock");
                break;
            case MOD_UNLOAD:
                smb_iod_done();
                error = smb_sm_done();
                if (error)
                        break;
                nsmb_dev_destroy();
                sx_destroy(&smb_lock);
                break;
            default:
                error = EINVAL;
                break;
        }
        return error;
}

DEV_MODULE (dev_netsmb, nsmb_dev_load, 0);

int
smb_dev2share(int fd, int mode, struct smb_cred *scred,
        struct smb_share **sspp, struct smb_dev **ssdp)
{
        struct file *fp, *fptmp;
        struct smb_dev *sdp;
        struct smb_share *ssp;
        struct thread *td;
        int error;

        td = curthread;
        error = fget(td, fd, &cap_read_rights, &fp);
        if (error)
                return (error);
        fptmp = td->td_fpop;
        td->td_fpop = fp;
        error = devfs_get_cdevpriv((void **)&sdp);
        td->td_fpop = fptmp;
        fdrop(fp, td);
        if (error || sdp == NULL)
                return (error);
        SMB_LOCK();
        *ssdp = sdp;
        ssp = sdp->sd_share;
        if (ssp == NULL) {
                SMB_UNLOCK();
                return (ENOTCONN);
        }
        error = smb_share_get(ssp, scred);
        if (error == 0) {
                sdp->refcount++;
                *sspp = ssp;
        }
        SMB_UNLOCK();
        return error;
}