// SPDX-License-Identifier: GPL-2.0

  /* ATM ioctl handling */
  
  /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
  /* 2003 John Levon  <levon@movementarian.org> */

  #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__

  #include <linux/module.h>
  #include <linux/kmod.h>
  #include <linux/net.h>		/* struct socket, struct proto_ops */
  #include <linux/atm.h>		/* ATM stuff */
  #include <linux/atmdev.h>
  #include <linux/atmclip.h>	/* CLIP_*ENCAP */
  #include <linux/atmarp.h>	/* manifest constants */

  #include <linux/capability.h>

  #include <linux/sonet.h>	/* for ioctls */
  #include <linux/atmsvc.h>
  #include <linux/atmmpc.h>
  #include <net/atmclip.h>
  #include <linux/atmlec.h>

  #include <linux/mutex.h>

  #include <asm/ioctls.h>

  #include <net/compat.h>

  
  #include "resources.h"
  #include "signaling.h"		/* for WAITING and sigd_attach */

  #include "common.h"

  static DEFINE_MUTEX(ioctl_mutex);

  static LIST_HEAD(ioctl_list);
  
  
  void register_atm_ioctl(struct atm_ioctl *ioctl)
  {

  	mutex_lock(&ioctl_mutex);

  	list_add_tail(&ioctl->list, &ioctl_list);

  	mutex_unlock(&ioctl_mutex);

  }

  EXPORT_SYMBOL(register_atm_ioctl);

  
  void deregister_atm_ioctl(struct atm_ioctl *ioctl)
  {

  	mutex_lock(&ioctl_mutex);

  	list_del(&ioctl->list);

  	mutex_unlock(&ioctl_mutex);

  }

  EXPORT_SYMBOL(deregister_atm_ioctl);

  static int do_vcc_ioctl(struct socket *sock, unsigned int cmd,
  			unsigned long arg, int compat)

  {
  	struct sock *sk = sock->sk;
  	struct atm_vcc *vcc;
  	int error;

  	struct list_head *pos;

  	void __user *argp = (void __user *)arg;
  
  	vcc = ATM_SD(sock);
  	switch (cmd) {

  	case SIOCOUTQ:
  		if (sock->state != SS_CONNECTED ||
  		    !test_bit(ATM_VF_READY, &vcc->flags)) {
  			error =  -EINVAL;
  			goto done;
  		}
  		error = put_user(sk->sk_sndbuf - sk_wmem_alloc_get(sk),
  				 (int __user *)argp) ? -EFAULT : 0;
  		goto done;
  	case SIOCINQ:
  	{
  		struct sk_buff *skb;
  
  		if (sock->state != SS_CONNECTED) {
  			error = -EINVAL;

  			goto done;

  		}
  		skb = skb_peek(&sk->sk_receive_queue);
  		error = put_user(skb ? skb->len : 0,
  				 (int __user *)argp) ? -EFAULT : 0;
  		goto done;
  	}

  	case ATM_SETSC:

  		net_warn_ratelimited("ATM_SETSC is obsolete; used by %s:%d
  ",
  				     current->comm, task_pid_nr(current));

  		error = 0;
  		goto done;
  	case ATMSIGD_CTRL:
  		if (!capable(CAP_NET_ADMIN)) {
  			error = -EPERM;

  			goto done;

  		}
  		/*
  		 * The user/kernel protocol for exchanging signalling
  		 * info uses kernel pointers as opaque references,
  		 * so the holder of the file descriptor can scribble
  		 * on the kernel... so we should make sure that we
  		 * have the same privileges that /proc/kcore needs
  		 */
  		if (!capable(CAP_SYS_RAWIO)) {
  			error = -EPERM;

  			goto done;

  		}

  #ifdef CONFIG_COMPAT

  		/* WTF? I don't even want to _think_ about making this
  		   work for 32-bit userspace. TBH I don't really want
  		   to think about it at all. dwmw2. */
  		if (compat) {

  			net_warn_ratelimited("32-bit task cannot be atmsigd
  ");

  			error = -EINVAL;
  			goto done;
  		}

  #endif

  		error = sigd_attach(vcc);
  		if (!error)
  			sock->state = SS_CONNECTED;
  		goto done;
  	case ATM_SETBACKEND:
  	case ATM_NEWBACKENDIF:
  	{
  		atm_backend_t backend;
  		error = get_user(backend, (atm_backend_t __user *)argp);
  		if (error)

  			goto done;

  		switch (backend) {
  		case ATM_BACKEND_PPP:
  			request_module("pppoatm");

  			break;

  		case ATM_BACKEND_BR2684:
  			request_module("br2684");

  			break;

  		}
  		break;
  	}
  	case ATMMPC_CTRL:
  	case ATMMPC_DATA:
  		request_module("mpoa");
  		break;
  	case ATMARPD_CTRL:
  		request_module("clip");
  		break;
  	case ATMLEC_CTRL:
  		request_module("lec");
  		break;

  	}

  	error = -ENOIOCTLCMD;

  	mutex_lock(&ioctl_mutex);

  	list_for_each(pos, &ioctl_list) {

  		struct atm_ioctl *ic = list_entry(pos, struct atm_ioctl, list);

  		if (try_module_get(ic->owner)) {
  			error = ic->ioctl(sock, cmd, arg);
  			module_put(ic->owner);
  			if (error != -ENOIOCTLCMD)
  				break;
  		}
  	}

  	mutex_unlock(&ioctl_mutex);

  
  	if (error != -ENOIOCTLCMD)
  		goto done;

  	error = atm_dev_ioctl(cmd, argp, compat);

  
  done:
  	return error;
  }

  int vcc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
  {
  	return do_vcc_ioctl(sock, cmd, arg, 0);
  }
  
  #ifdef CONFIG_COMPAT

  /*
   * FIXME:
   * The compat_ioctl handling is duplicated, using both these conversion
   * routines and the compat argument to the actual handlers. Both
   * versions are somewhat incomplete and should be merged, e.g. by
   * moving the ioctl number translation into the actual handlers and
   * killing the conversion code.
   *
   * -arnd, November 2009
   */
  #define ATM_GETLINKRATE32 _IOW('a', ATMIOC_ITF+1, struct compat_atmif_sioc)
  #define ATM_GETNAMES32    _IOW('a', ATMIOC_ITF+3, struct compat_atm_iobuf)
  #define ATM_GETTYPE32     _IOW('a', ATMIOC_ITF+4, struct compat_atmif_sioc)
  #define ATM_GETESI32	  _IOW('a', ATMIOC_ITF+5, struct compat_atmif_sioc)
  #define ATM_GETADDR32	  _IOW('a', ATMIOC_ITF+6, struct compat_atmif_sioc)
  #define ATM_RSTADDR32	  _IOW('a', ATMIOC_ITF+7, struct compat_atmif_sioc)
  #define ATM_ADDADDR32	  _IOW('a', ATMIOC_ITF+8, struct compat_atmif_sioc)
  #define ATM_DELADDR32	  _IOW('a', ATMIOC_ITF+9, struct compat_atmif_sioc)
  #define ATM_GETCIRANGE32  _IOW('a', ATMIOC_ITF+10, struct compat_atmif_sioc)
  #define ATM_SETCIRANGE32  _IOW('a', ATMIOC_ITF+11, struct compat_atmif_sioc)
  #define ATM_SETESI32      _IOW('a', ATMIOC_ITF+12, struct compat_atmif_sioc)
  #define ATM_SETESIF32     _IOW('a', ATMIOC_ITF+13, struct compat_atmif_sioc)
  #define ATM_GETSTAT32     _IOW('a', ATMIOC_SARCOM+0, struct compat_atmif_sioc)
  #define ATM_GETSTATZ32    _IOW('a', ATMIOC_SARCOM+1, struct compat_atmif_sioc)
  #define ATM_GETLOOP32	  _IOW('a', ATMIOC_SARCOM+2, struct compat_atmif_sioc)
  #define ATM_SETLOOP32	  _IOW('a', ATMIOC_SARCOM+3, struct compat_atmif_sioc)
  #define ATM_QUERYLOOP32	  _IOW('a', ATMIOC_SARCOM+4, struct compat_atmif_sioc)
  
  static struct {
  	unsigned int cmd32;
  	unsigned int cmd;
  } atm_ioctl_map[] = {
  	{ ATM_GETLINKRATE32, ATM_GETLINKRATE },
  	{ ATM_GETNAMES32,    ATM_GETNAMES },
  	{ ATM_GETTYPE32,     ATM_GETTYPE },
  	{ ATM_GETESI32,	     ATM_GETESI },
  	{ ATM_GETADDR32,     ATM_GETADDR },
  	{ ATM_RSTADDR32,     ATM_RSTADDR },
  	{ ATM_ADDADDR32,     ATM_ADDADDR },
  	{ ATM_DELADDR32,     ATM_DELADDR },
  	{ ATM_GETCIRANGE32,  ATM_GETCIRANGE },
  	{ ATM_SETCIRANGE32,  ATM_SETCIRANGE },
  	{ ATM_SETESI32,	     ATM_SETESI },
  	{ ATM_SETESIF32,     ATM_SETESIF },
  	{ ATM_GETSTAT32,     ATM_GETSTAT },
  	{ ATM_GETSTATZ32,    ATM_GETSTATZ },
  	{ ATM_GETLOOP32,     ATM_GETLOOP },
  	{ ATM_SETLOOP32,     ATM_SETLOOP },
  	{ ATM_QUERYLOOP32,   ATM_QUERYLOOP },
  };
  
  #define NR_ATM_IOCTL ARRAY_SIZE(atm_ioctl_map)
  
  static int do_atm_iobuf(struct socket *sock, unsigned int cmd,
  			unsigned long arg)
  {
  	struct atm_iobuf __user *iobuf;
  	struct compat_atm_iobuf __user *iobuf32;
  	u32 data;
  	void __user *datap;
  	int len, err;
  
  	iobuf = compat_alloc_user_space(sizeof(*iobuf));
  	iobuf32 = compat_ptr(arg);
  
  	if (get_user(len, &iobuf32->length) ||
  	    get_user(data, &iobuf32->buffer))
  		return -EFAULT;
  	datap = compat_ptr(data);
  	if (put_user(len, &iobuf->length) ||
  	    put_user(datap, &iobuf->buffer))
  		return -EFAULT;
  
  	err = do_vcc_ioctl(sock, cmd, (unsigned long) iobuf, 0);
  
  	if (!err) {
  		if (copy_in_user(&iobuf32->length, &iobuf->length,
  				 sizeof(int)))
  			err = -EFAULT;
  	}
  
  	return err;
  }
  
  static int do_atmif_sioc(struct socket *sock, unsigned int cmd,
  			 unsigned long arg)
  {
  	struct atmif_sioc __user *sioc;
  	struct compat_atmif_sioc __user *sioc32;
  	u32 data;
  	void __user *datap;
  	int err;
  
  	sioc = compat_alloc_user_space(sizeof(*sioc));
  	sioc32 = compat_ptr(arg);

  	if (copy_in_user(&sioc->number, &sioc32->number, 2 * sizeof(int)) ||
  	    get_user(data, &sioc32->arg))

  		return -EFAULT;
  	datap = compat_ptr(data);
  	if (put_user(datap, &sioc->arg))
  		return -EFAULT;
  
  	err = do_vcc_ioctl(sock, cmd, (unsigned long) sioc, 0);
  
  	if (!err) {
  		if (copy_in_user(&sioc32->length, &sioc->length,
  				 sizeof(int)))
  			err = -EFAULT;
  	}
  	return err;
  }
  
  static int do_atm_ioctl(struct socket *sock, unsigned int cmd32,
  			unsigned long arg)
  {
  	int i;
  	unsigned int cmd = 0;
  
  	switch (cmd32) {
  	case SONET_GETSTAT:
  	case SONET_GETSTATZ:
  	case SONET_GETDIAG:
  	case SONET_SETDIAG:
  	case SONET_CLRDIAG:
  	case SONET_SETFRAMING:
  	case SONET_GETFRAMING:
  	case SONET_GETFRSENSE:
  		return do_atmif_sioc(sock, cmd32, arg);
  	}
  
  	for (i = 0; i < NR_ATM_IOCTL; i++) {
  		if (cmd32 == atm_ioctl_map[i].cmd32) {
  			cmd = atm_ioctl_map[i].cmd;
  			break;
  		}
  	}
  	if (i == NR_ATM_IOCTL)
  		return -EINVAL;
  
  	switch (cmd) {
  	case ATM_GETNAMES:
  		return do_atm_iobuf(sock, cmd, arg);
  
  	case ATM_GETLINKRATE:
  	case ATM_GETTYPE:
  	case ATM_GETESI:
  	case ATM_GETADDR:
  	case ATM_RSTADDR:
  	case ATM_ADDADDR:
  	case ATM_DELADDR:
  	case ATM_GETCIRANGE:
  	case ATM_SETCIRANGE:
  	case ATM_SETESI:
  	case ATM_SETESIF:
  	case ATM_GETSTAT:
  	case ATM_GETSTATZ:
  	case ATM_GETLOOP:
  	case ATM_SETLOOP:
  	case ATM_QUERYLOOP:
  		return do_atmif_sioc(sock, cmd, arg);
  	}
  
  	return -EINVAL;
  }
  
  int vcc_compat_ioctl(struct socket *sock, unsigned int cmd,
  		     unsigned long arg)

  {

  	int ret;
  
  	ret = do_vcc_ioctl(sock, cmd, arg, 1);
  	if (ret != -ENOIOCTLCMD)
  		return ret;
  
  	return do_atm_ioctl(sock, cmd, arg);

  }
  #endif