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87 		net_warn_ratelimited("ATM_SETSC is obsolete; used by %s:%d\n",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