1// SPDX-License-Identifier: GPL-2.0
2/* ATM ioctl handling */
3
4/* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
5/* 2003 John Levon  <levon@movementarian.org> */
6
7#define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
8
9#include <linux/module.h>
10#include <linux/kmod.h>
11#include <linux/net.h>		/* struct socket, struct proto_ops */
12#include <linux/atm.h>		/* ATM stuff */
13#include <linux/atmdev.h>
14#include <linux/atmclip.h>	/* CLIP_*ENCAP */
15#include <linux/atmarp.h>	/* manifest constants */
16#include <linux/capability.h>
17#include <linux/sonet.h>	/* for ioctls */
18#include <linux/atmsvc.h>
19#include <linux/atmmpc.h>
20#include <net/atmclip.h>
21#include <linux/atmlec.h>
22#include <linux/mutex.h>
23#include <asm/ioctls.h>
24#include <net/compat.h>
25
26#include "resources.h"
27#include "signaling.h"		/* for WAITING and sigd_attach */
28#include "common.h"
29
30
31static DEFINE_MUTEX(ioctl_mutex);
32static LIST_HEAD(ioctl_list);
33
34
35void register_atm_ioctl(struct atm_ioctl *ioctl)
36{
37	mutex_lock(&ioctl_mutex);
38	list_add_tail(&ioctl->list, &ioctl_list);
39	mutex_unlock(&ioctl_mutex);
40}
41EXPORT_SYMBOL(register_atm_ioctl);
42
43void deregister_atm_ioctl(struct atm_ioctl *ioctl)
44{
45	mutex_lock(&ioctl_mutex);
46	list_del(&ioctl->list);
47	mutex_unlock(&ioctl_mutex);
48}
49EXPORT_SYMBOL(deregister_atm_ioctl);
50
51static int do_vcc_ioctl(struct socket *sock, unsigned int cmd,
52			unsigned long arg, int compat)
53{
54	struct sock *sk = sock->sk;
55	struct atm_vcc *vcc;
56	int error;
57	struct list_head *pos;
58	void __user *argp = (void __user *)arg;
59	void __user *buf;
60	int __user *len;
61
62	vcc = ATM_SD(sock);
63	switch (cmd) {
64	case SIOCOUTQ:
65		if (sock->state != SS_CONNECTED ||
66		    !test_bit(ATM_VF_READY, &vcc->flags)) {
67			error =  -EINVAL;
68			goto done;
69		}
70		error = put_user(sk->sk_sndbuf - sk_wmem_alloc_get(sk),
71				 (int __user *)argp) ? -EFAULT : 0;
72		goto done;
73	case SIOCINQ:
74	{
75		struct sk_buff *skb;
76		int amount;
77
78		if (sock->state != SS_CONNECTED) {
79			error = -EINVAL;
80			goto done;
81		}
82		spin_lock_irq(&sk->sk_receive_queue.lock);
83		skb = skb_peek(&sk->sk_receive_queue);
84		amount = skb ? skb->len : 0;
85		spin_unlock_irq(&sk->sk_receive_queue.lock);
86		error = put_user(amount, (int __user *)argp) ? -EFAULT : 0;
87		goto done;
88	}
89	case ATM_SETSC:
90		net_warn_ratelimited("ATM_SETSC is obsolete; used by %s:%d\n",
91				     current->comm, task_pid_nr(current));
92		error = 0;
93		goto done;
94	case ATMSIGD_CTRL:
95		if (!capable(CAP_NET_ADMIN)) {
96			error = -EPERM;
97			goto done;
98		}
99		/*
100		 * The user/kernel protocol for exchanging signalling
101		 * info uses kernel pointers as opaque references,
102		 * so the holder of the file descriptor can scribble
103		 * on the kernel... so we should make sure that we
104		 * have the same privileges that /proc/kcore needs
105		 */
106		if (!capable(CAP_SYS_RAWIO)) {
107			error = -EPERM;
108			goto done;
109		}
110#ifdef CONFIG_COMPAT
111		/* WTF? I don't even want to _think_ about making this
112		   work for 32-bit userspace. TBH I don't really want
113		   to think about it at all. dwmw2. */
114		if (compat) {
115			net_warn_ratelimited("32-bit task cannot be atmsigd\n");
116			error = -EINVAL;
117			goto done;
118		}
119#endif
120		error = sigd_attach(vcc);
121		if (!error)
122			sock->state = SS_CONNECTED;
123		goto done;
124	case ATM_SETBACKEND:
125	case ATM_NEWBACKENDIF:
126	{
127		atm_backend_t backend;
128		error = get_user(backend, (atm_backend_t __user *)argp);
129		if (error)
130			goto done;
131		switch (backend) {
132		case ATM_BACKEND_PPP:
133			request_module("pppoatm");
134			break;
135		case ATM_BACKEND_BR2684:
136			request_module("br2684");
137			break;
138		}
139		break;
140	}
141	case ATMMPC_CTRL:
142	case ATMMPC_DATA:
143		request_module("mpoa");
144		break;
145	case ATMARPD_CTRL:
146		request_module("clip");
147		break;
148	case ATMLEC_CTRL:
149		request_module("lec");
150		break;
151	}
152
153	error = -ENOIOCTLCMD;
154
155	mutex_lock(&ioctl_mutex);
156	list_for_each(pos, &ioctl_list) {
157		struct atm_ioctl *ic = list_entry(pos, struct atm_ioctl, list);
158		if (try_module_get(ic->owner)) {
159			error = ic->ioctl(sock, cmd, arg);
160			module_put(ic->owner);
161			if (error != -ENOIOCTLCMD)
162				break;
163		}
164	}
165	mutex_unlock(&ioctl_mutex);
166
167	if (error != -ENOIOCTLCMD)
168		goto done;
169
170	if (cmd == ATM_GETNAMES) {
171		if (IS_ENABLED(CONFIG_COMPAT) && compat) {
172#ifdef CONFIG_COMPAT
173			struct compat_atm_iobuf __user *ciobuf = argp;
174			compat_uptr_t cbuf;
175			len = &ciobuf->length;
176			if (get_user(cbuf, &ciobuf->buffer))
177				return -EFAULT;
178			buf = compat_ptr(cbuf);
179#endif
180		} else {
181			struct atm_iobuf __user *iobuf = argp;
182			len = &iobuf->length;
183			if (get_user(buf, &iobuf->buffer))
184				return -EFAULT;
185		}
186		error = atm_getnames(buf, len);
187	} else {
188		int number;
189
190		if (IS_ENABLED(CONFIG_COMPAT) && compat) {
191#ifdef CONFIG_COMPAT
192			struct compat_atmif_sioc __user *csioc = argp;
193			compat_uptr_t carg;
194
195			len = &csioc->length;
196			if (get_user(carg, &csioc->arg))
197				return -EFAULT;
198			buf = compat_ptr(carg);
199			if (get_user(number, &csioc->number))
200				return -EFAULT;
201#endif
202		} else {
203			struct atmif_sioc __user *sioc = argp;
204
205			len = &sioc->length;
206			if (get_user(buf, &sioc->arg))
207				return -EFAULT;
208			if (get_user(number, &sioc->number))
209				return -EFAULT;
210		}
211		error = atm_dev_ioctl(cmd, buf, len, number, compat);
212	}
213
214done:
215	return error;
216}
217
218int vcc_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
219{
220	return do_vcc_ioctl(sock, cmd, arg, 0);
221}
222
223#ifdef CONFIG_COMPAT
224/*
225 * FIXME:
226 * The compat_ioctl handling is duplicated, using both these conversion
227 * routines and the compat argument to the actual handlers. Both
228 * versions are somewhat incomplete and should be merged, e.g. by
229 * moving the ioctl number translation into the actual handlers and
230 * killing the conversion code.
231 *
232 * -arnd, November 2009
233 */
234#define ATM_GETLINKRATE32 _IOW('a', ATMIOC_ITF+1, struct compat_atmif_sioc)
235#define ATM_GETNAMES32    _IOW('a', ATMIOC_ITF+3, struct compat_atm_iobuf)
236#define ATM_GETTYPE32     _IOW('a', ATMIOC_ITF+4, struct compat_atmif_sioc)
237#define ATM_GETESI32	  _IOW('a', ATMIOC_ITF+5, struct compat_atmif_sioc)
238#define ATM_GETADDR32	  _IOW('a', ATMIOC_ITF+6, struct compat_atmif_sioc)
239#define ATM_RSTADDR32	  _IOW('a', ATMIOC_ITF+7, struct compat_atmif_sioc)
240#define ATM_ADDADDR32	  _IOW('a', ATMIOC_ITF+8, struct compat_atmif_sioc)
241#define ATM_DELADDR32	  _IOW('a', ATMIOC_ITF+9, struct compat_atmif_sioc)
242#define ATM_GETCIRANGE32  _IOW('a', ATMIOC_ITF+10, struct compat_atmif_sioc)
243#define ATM_SETCIRANGE32  _IOW('a', ATMIOC_ITF+11, struct compat_atmif_sioc)
244#define ATM_SETESI32      _IOW('a', ATMIOC_ITF+12, struct compat_atmif_sioc)
245#define ATM_SETESIF32     _IOW('a', ATMIOC_ITF+13, struct compat_atmif_sioc)
246#define ATM_GETSTAT32     _IOW('a', ATMIOC_SARCOM+0, struct compat_atmif_sioc)
247#define ATM_GETSTATZ32    _IOW('a', ATMIOC_SARCOM+1, struct compat_atmif_sioc)
248#define ATM_GETLOOP32	  _IOW('a', ATMIOC_SARCOM+2, struct compat_atmif_sioc)
249#define ATM_SETLOOP32	  _IOW('a', ATMIOC_SARCOM+3, struct compat_atmif_sioc)
250#define ATM_QUERYLOOP32	  _IOW('a', ATMIOC_SARCOM+4, struct compat_atmif_sioc)
251
252static struct {
253	unsigned int cmd32;
254	unsigned int cmd;
255} atm_ioctl_map[] = {
256	{ ATM_GETLINKRATE32, ATM_GETLINKRATE },
257	{ ATM_GETNAMES32,    ATM_GETNAMES },
258	{ ATM_GETTYPE32,     ATM_GETTYPE },
259	{ ATM_GETESI32,	     ATM_GETESI },
260	{ ATM_GETADDR32,     ATM_GETADDR },
261	{ ATM_RSTADDR32,     ATM_RSTADDR },
262	{ ATM_ADDADDR32,     ATM_ADDADDR },
263	{ ATM_DELADDR32,     ATM_DELADDR },
264	{ ATM_GETCIRANGE32,  ATM_GETCIRANGE },
265	{ ATM_SETCIRANGE32,  ATM_SETCIRANGE },
266	{ ATM_SETESI32,	     ATM_SETESI },
267	{ ATM_SETESIF32,     ATM_SETESIF },
268	{ ATM_GETSTAT32,     ATM_GETSTAT },
269	{ ATM_GETSTATZ32,    ATM_GETSTATZ },
270	{ ATM_GETLOOP32,     ATM_GETLOOP },
271	{ ATM_SETLOOP32,     ATM_SETLOOP },
272	{ ATM_QUERYLOOP32,   ATM_QUERYLOOP },
273};
274
275#define NR_ATM_IOCTL ARRAY_SIZE(atm_ioctl_map)
276
277static int do_atm_iobuf(struct socket *sock, unsigned int cmd,
278			unsigned long arg)
279{
280	struct compat_atm_iobuf __user *iobuf32 = compat_ptr(arg);
281	u32 data;
282
283	if (get_user(data, &iobuf32->buffer))
284		return -EFAULT;
285
286	return atm_getnames(&iobuf32->length, compat_ptr(data));
287}
288
289static int do_atmif_sioc(struct socket *sock, unsigned int cmd,
290			 unsigned long arg)
291{
292	struct compat_atmif_sioc __user *sioc32 = compat_ptr(arg);
293	int number;
294	u32 data;
295
296	if (get_user(data, &sioc32->arg) || get_user(number, &sioc32->number))
297		return -EFAULT;
298	return atm_dev_ioctl(cmd, compat_ptr(data), &sioc32->length, number, 0);
299}
300
301static int do_atm_ioctl(struct socket *sock, unsigned int cmd32,
302			unsigned long arg)
303{
304	int i;
305	unsigned int cmd = 0;
306
307	switch (cmd32) {
308	case SONET_GETSTAT:
309	case SONET_GETSTATZ:
310	case SONET_GETDIAG:
311	case SONET_SETDIAG:
312	case SONET_CLRDIAG:
313	case SONET_SETFRAMING:
314	case SONET_GETFRAMING:
315	case SONET_GETFRSENSE:
316		return do_atmif_sioc(sock, cmd32, arg);
317	}
318
319	for (i = 0; i < NR_ATM_IOCTL; i++) {
320		if (cmd32 == atm_ioctl_map[i].cmd32) {
321			cmd = atm_ioctl_map[i].cmd;
322			break;
323		}
324	}
325	if (i == NR_ATM_IOCTL)
326		return -EINVAL;
327
328	switch (cmd) {
329	case ATM_GETNAMES:
330		return do_atm_iobuf(sock, cmd, arg);
331
332	case ATM_GETLINKRATE:
333	case ATM_GETTYPE:
334	case ATM_GETESI:
335	case ATM_GETADDR:
336	case ATM_RSTADDR:
337	case ATM_ADDADDR:
338	case ATM_DELADDR:
339	case ATM_GETCIRANGE:
340	case ATM_SETCIRANGE:
341	case ATM_SETESI:
342	case ATM_SETESIF:
343	case ATM_GETSTAT:
344	case ATM_GETSTATZ:
345	case ATM_GETLOOP:
346	case ATM_SETLOOP:
347	case ATM_QUERYLOOP:
348		return do_atmif_sioc(sock, cmd, arg);
349	}
350
351	return -EINVAL;
352}
353
354int vcc_compat_ioctl(struct socket *sock, unsigned int cmd,
355		     unsigned long arg)
356{
357	int ret;
358
359	ret = do_vcc_ioctl(sock, cmd, arg, 1);
360	if (ret != -ENOIOCTLCMD)
361		return ret;
362
363	return do_atm_ioctl(sock, cmd, arg);
364}
365#endif
366