1 // SPDX-License-Identifier: GPL-2.0
2 /* net/atm/proc.c - ATM /proc interface
3  *
4  * Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA
5  *
6  * seq_file api usage by romieu@fr.zoreil.com
7  *
8  * Evaluating the efficiency of the whole thing if left as an exercise to
9  * the reader.
10  */
11 
12 #include <linux/module.h> /* for EXPORT_SYMBOL */
13 #include <linux/string.h>
14 #include <linux/types.h>
15 #include <linux/mm.h>
16 #include <linux/fs.h>
17 #include <linux/stat.h>
18 #include <linux/proc_fs.h>
19 #include <linux/seq_file.h>
20 #include <linux/errno.h>
21 #include <linux/atm.h>
22 #include <linux/atmdev.h>
23 #include <linux/netdevice.h>
24 #include <linux/atmclip.h>
25 #include <linux/init.h> /* for __init */
26 #include <linux/slab.h>
27 #include <net/net_namespace.h>
28 #include <net/atmclip.h>
29 #include <linux/uaccess.h>
30 #include <linux/param.h> /* for HZ */
31 #include <linux/atomic.h>
32 #include "resources.h"
33 #include "common.h" /* atm_proc_init prototype */
34 #include "signaling.h" /* to get sigd - ugly too */
35 
36 static ssize_t proc_dev_atm_read(struct file *file, char __user *buf,
37 				 size_t count, loff_t *pos);
38 
39 static const struct proc_ops atm_dev_proc_ops = {
40 	.proc_read	= proc_dev_atm_read,
41 	.proc_lseek	= noop_llseek,
42 };
43 
add_stats(struct seq_file * seq,const char * aal,const struct k_atm_aal_stats * stats)44 static void add_stats(struct seq_file *seq, const char *aal,
45   const struct k_atm_aal_stats *stats)
46 {
47 	seq_printf(seq, "%s ( %d %d %d %d %d )", aal,
48 		   atomic_read(&stats->tx), atomic_read(&stats->tx_err),
49 		   atomic_read(&stats->rx), atomic_read(&stats->rx_err),
50 		   atomic_read(&stats->rx_drop));
51 }
52 
atm_dev_info(struct seq_file * seq,const struct atm_dev * dev)53 static void atm_dev_info(struct seq_file *seq, const struct atm_dev *dev)
54 {
55 	int i;
56 
57 	seq_printf(seq, "%3d %-8s", dev->number, dev->type);
58 	for (i = 0; i < ESI_LEN; i++)
59 		seq_printf(seq, "%02x", dev->esi[i]);
60 	seq_puts(seq, "  ");
61 	add_stats(seq, "0", &dev->stats.aal0);
62 	seq_puts(seq, "  ");
63 	add_stats(seq, "5", &dev->stats.aal5);
64 	seq_printf(seq, "\t[%d]", refcount_read(&dev->refcnt));
65 	seq_putc(seq, '\n');
66 }
67 
68 struct vcc_state {
69 	int bucket;
70 	struct sock *sk;
71 };
72 
compare_family(struct sock * sk,int family)73 static inline int compare_family(struct sock *sk, int family)
74 {
75 	return !family || (sk->sk_family == family);
76 }
77 
__vcc_walk(struct sock ** sock,int family,int * bucket,loff_t l)78 static int __vcc_walk(struct sock **sock, int family, int *bucket, loff_t l)
79 {
80 	struct sock *sk = *sock;
81 
82 	if (sk == SEQ_START_TOKEN) {
83 		for (*bucket = 0; *bucket < VCC_HTABLE_SIZE; ++*bucket) {
84 			struct hlist_head *head = &vcc_hash[*bucket];
85 
86 			sk = hlist_empty(head) ? NULL : __sk_head(head);
87 			if (sk)
88 				break;
89 		}
90 		l--;
91 	}
92 try_again:
93 	for (; sk; sk = sk_next(sk)) {
94 		l -= compare_family(sk, family);
95 		if (l < 0)
96 			goto out;
97 	}
98 	if (!sk && ++*bucket < VCC_HTABLE_SIZE) {
99 		sk = sk_head(&vcc_hash[*bucket]);
100 		goto try_again;
101 	}
102 	sk = SEQ_START_TOKEN;
103 out:
104 	*sock = sk;
105 	return (l < 0);
106 }
107 
vcc_walk(struct seq_file * seq,loff_t l)108 static inline void *vcc_walk(struct seq_file *seq, loff_t l)
109 {
110 	struct vcc_state *state = seq->private;
111 	int family = (uintptr_t)(PDE_DATA(file_inode(seq->file)));
112 
113 	return __vcc_walk(&state->sk, family, &state->bucket, l) ?
114 	       state : NULL;
115 }
116 
vcc_seq_start(struct seq_file * seq,loff_t * pos)117 static void *vcc_seq_start(struct seq_file *seq, loff_t *pos)
118 	__acquires(vcc_sklist_lock)
119 {
120 	struct vcc_state *state = seq->private;
121 	loff_t left = *pos;
122 
123 	read_lock(&vcc_sklist_lock);
124 	state->sk = SEQ_START_TOKEN;
125 	return left ? vcc_walk(seq, left) : SEQ_START_TOKEN;
126 }
127 
vcc_seq_stop(struct seq_file * seq,void * v)128 static void vcc_seq_stop(struct seq_file *seq, void *v)
129 	__releases(vcc_sklist_lock)
130 {
131 	read_unlock(&vcc_sklist_lock);
132 }
133 
vcc_seq_next(struct seq_file * seq,void * v,loff_t * pos)134 static void *vcc_seq_next(struct seq_file *seq, void *v, loff_t *pos)
135 {
136 	v = vcc_walk(seq, 1);
137 	(*pos)++;
138 	return v;
139 }
140 
pvc_info(struct seq_file * seq,struct atm_vcc * vcc)141 static void pvc_info(struct seq_file *seq, struct atm_vcc *vcc)
142 {
143 	static const char *const class_name[] = {
144 		"off", "UBR", "CBR", "VBR", "ABR"};
145 	static const char *const aal_name[] = {
146 		"---",	"1",	"2",	"3/4",	/*  0- 3 */
147 		"???",	"5",	"???",	"???",	/*  4- 7 */
148 		"???",	"???",	"???",	"???",	/*  8-11 */
149 		"???",	"0",	"???",	"???"};	/* 12-15 */
150 
151 	seq_printf(seq, "%3d %3d %5d %-3s %7d %-5s %7d %-6s",
152 		   vcc->dev->number, vcc->vpi, vcc->vci,
153 		   vcc->qos.aal >= ARRAY_SIZE(aal_name) ? "err" :
154 		   aal_name[vcc->qos.aal], vcc->qos.rxtp.min_pcr,
155 		   class_name[vcc->qos.rxtp.traffic_class],
156 		   vcc->qos.txtp.min_pcr,
157 		   class_name[vcc->qos.txtp.traffic_class]);
158 	if (test_bit(ATM_VF_IS_CLIP, &vcc->flags)) {
159 		struct clip_vcc *clip_vcc = CLIP_VCC(vcc);
160 		struct net_device *dev;
161 
162 		dev = clip_vcc->entry ? clip_vcc->entry->neigh->dev : NULL;
163 		seq_printf(seq, "CLIP, Itf:%s, Encap:",
164 		    dev ? dev->name : "none?");
165 		seq_printf(seq, "%s", clip_vcc->encap ? "LLC/SNAP" : "None");
166 	}
167 	seq_putc(seq, '\n');
168 }
169 
vcc_state(struct atm_vcc * vcc)170 static const char *vcc_state(struct atm_vcc *vcc)
171 {
172 	static const char *const map[] = { ATM_VS2TXT_MAP };
173 
174 	return map[ATM_VF2VS(vcc->flags)];
175 }
176 
vcc_info(struct seq_file * seq,struct atm_vcc * vcc)177 static void vcc_info(struct seq_file *seq, struct atm_vcc *vcc)
178 {
179 	struct sock *sk = sk_atm(vcc);
180 
181 	seq_printf(seq, "%pK ", vcc);
182 	if (!vcc->dev)
183 		seq_printf(seq, "Unassigned    ");
184 	else
185 		seq_printf(seq, "%3d %3d %5d ", vcc->dev->number, vcc->vpi,
186 			vcc->vci);
187 	switch (sk->sk_family) {
188 	case AF_ATMPVC:
189 		seq_printf(seq, "PVC");
190 		break;
191 	case AF_ATMSVC:
192 		seq_printf(seq, "SVC");
193 		break;
194 	default:
195 		seq_printf(seq, "%3d", sk->sk_family);
196 	}
197 	seq_printf(seq, " %04lx  %5d %7d/%7d %7d/%7d [%d]\n",
198 		   vcc->flags, sk->sk_err,
199 		   sk_wmem_alloc_get(sk), sk->sk_sndbuf,
200 		   sk_rmem_alloc_get(sk), sk->sk_rcvbuf,
201 		   refcount_read(&sk->sk_refcnt));
202 }
203 
svc_info(struct seq_file * seq,struct atm_vcc * vcc)204 static void svc_info(struct seq_file *seq, struct atm_vcc *vcc)
205 {
206 	if (!vcc->dev)
207 		seq_printf(seq, sizeof(void *) == 4 ?
208 			   "N/A@%pK%10s" : "N/A@%pK%2s", vcc, "");
209 	else
210 		seq_printf(seq, "%3d %3d %5d         ",
211 			   vcc->dev->number, vcc->vpi, vcc->vci);
212 	seq_printf(seq, "%-10s ", vcc_state(vcc));
213 	seq_printf(seq, "%s%s", vcc->remote.sas_addr.pub,
214 	    *vcc->remote.sas_addr.pub && *vcc->remote.sas_addr.prv ? "+" : "");
215 	if (*vcc->remote.sas_addr.prv) {
216 		int i;
217 
218 		for (i = 0; i < ATM_ESA_LEN; i++)
219 			seq_printf(seq, "%02x", vcc->remote.sas_addr.prv[i]);
220 	}
221 	seq_putc(seq, '\n');
222 }
223 
atm_dev_seq_show(struct seq_file * seq,void * v)224 static int atm_dev_seq_show(struct seq_file *seq, void *v)
225 {
226 	static char atm_dev_banner[] =
227 		"Itf Type    ESI/\"MAC\"addr "
228 		"AAL(TX,err,RX,err,drop) ...               [refcnt]\n";
229 
230 	if (v == &atm_devs)
231 		seq_puts(seq, atm_dev_banner);
232 	else {
233 		struct atm_dev *dev = list_entry(v, struct atm_dev, dev_list);
234 
235 		atm_dev_info(seq, dev);
236 	}
237 	return 0;
238 }
239 
240 static const struct seq_operations atm_dev_seq_ops = {
241 	.start	= atm_dev_seq_start,
242 	.next	= atm_dev_seq_next,
243 	.stop	= atm_dev_seq_stop,
244 	.show	= atm_dev_seq_show,
245 };
246 
pvc_seq_show(struct seq_file * seq,void * v)247 static int pvc_seq_show(struct seq_file *seq, void *v)
248 {
249 	static char atm_pvc_banner[] =
250 		"Itf VPI VCI   AAL RX(PCR,Class) TX(PCR,Class)\n";
251 
252 	if (v == SEQ_START_TOKEN)
253 		seq_puts(seq, atm_pvc_banner);
254 	else {
255 		struct vcc_state *state = seq->private;
256 		struct atm_vcc *vcc = atm_sk(state->sk);
257 
258 		pvc_info(seq, vcc);
259 	}
260 	return 0;
261 }
262 
263 static const struct seq_operations pvc_seq_ops = {
264 	.start	= vcc_seq_start,
265 	.next	= vcc_seq_next,
266 	.stop	= vcc_seq_stop,
267 	.show	= pvc_seq_show,
268 };
269 
vcc_seq_show(struct seq_file * seq,void * v)270 static int vcc_seq_show(struct seq_file *seq, void *v)
271 {
272 	if (v == SEQ_START_TOKEN) {
273 		seq_printf(seq, sizeof(void *) == 4 ? "%-8s%s" : "%-16s%s",
274 			"Address ", "Itf VPI VCI   Fam Flags Reply "
275 			"Send buffer     Recv buffer      [refcnt]\n");
276 	} else {
277 		struct vcc_state *state = seq->private;
278 		struct atm_vcc *vcc = atm_sk(state->sk);
279 
280 		vcc_info(seq, vcc);
281 	}
282 	return 0;
283 }
284 
285 static const struct seq_operations vcc_seq_ops = {
286 	.start	= vcc_seq_start,
287 	.next	= vcc_seq_next,
288 	.stop	= vcc_seq_stop,
289 	.show	= vcc_seq_show,
290 };
291 
svc_seq_show(struct seq_file * seq,void * v)292 static int svc_seq_show(struct seq_file *seq, void *v)
293 {
294 	static const char atm_svc_banner[] =
295 		"Itf VPI VCI           State      Remote\n";
296 
297 	if (v == SEQ_START_TOKEN)
298 		seq_puts(seq, atm_svc_banner);
299 	else {
300 		struct vcc_state *state = seq->private;
301 		struct atm_vcc *vcc = atm_sk(state->sk);
302 
303 		svc_info(seq, vcc);
304 	}
305 	return 0;
306 }
307 
308 static const struct seq_operations svc_seq_ops = {
309 	.start	= vcc_seq_start,
310 	.next	= vcc_seq_next,
311 	.stop	= vcc_seq_stop,
312 	.show	= svc_seq_show,
313 };
314 
proc_dev_atm_read(struct file * file,char __user * buf,size_t count,loff_t * pos)315 static ssize_t proc_dev_atm_read(struct file *file, char __user *buf,
316 				 size_t count, loff_t *pos)
317 {
318 	struct atm_dev *dev;
319 	unsigned long page;
320 	int length;
321 
322 	if (count == 0)
323 		return 0;
324 	page = get_zeroed_page(GFP_KERNEL);
325 	if (!page)
326 		return -ENOMEM;
327 	dev = PDE_DATA(file_inode(file));
328 	if (!dev->ops->proc_read)
329 		length = -EINVAL;
330 	else {
331 		length = dev->ops->proc_read(dev, pos, (char *)page);
332 		if (length > count)
333 			length = -EINVAL;
334 	}
335 	if (length >= 0) {
336 		if (copy_to_user(buf, (char *)page, length))
337 			length = -EFAULT;
338 		(*pos)++;
339 	}
340 	free_page(page);
341 	return length;
342 }
343 
344 struct proc_dir_entry *atm_proc_root;
345 EXPORT_SYMBOL(atm_proc_root);
346 
347 
atm_proc_dev_register(struct atm_dev * dev)348 int atm_proc_dev_register(struct atm_dev *dev)
349 {
350 	int error;
351 
352 	/* No proc info */
353 	if (!dev->ops->proc_read)
354 		return 0;
355 
356 	error = -ENOMEM;
357 	dev->proc_name = kasprintf(GFP_KERNEL, "%s:%d", dev->type, dev->number);
358 	if (!dev->proc_name)
359 		goto err_out;
360 
361 	dev->proc_entry = proc_create_data(dev->proc_name, 0, atm_proc_root,
362 					   &atm_dev_proc_ops, dev);
363 	if (!dev->proc_entry)
364 		goto err_free_name;
365 	return 0;
366 
367 err_free_name:
368 	kfree(dev->proc_name);
369 err_out:
370 	return error;
371 }
372 
atm_proc_dev_deregister(struct atm_dev * dev)373 void atm_proc_dev_deregister(struct atm_dev *dev)
374 {
375 	if (!dev->ops->proc_read)
376 		return;
377 
378 	remove_proc_entry(dev->proc_name, atm_proc_root);
379 	kfree(dev->proc_name);
380 }
381 
atm_proc_init(void)382 int __init atm_proc_init(void)
383 {
384 	atm_proc_root = proc_net_mkdir(&init_net, "atm", init_net.proc_net);
385 	if (!atm_proc_root)
386 		return -ENOMEM;
387 	proc_create_seq("devices", 0444, atm_proc_root, &atm_dev_seq_ops);
388 	proc_create_seq_private("pvc", 0444, atm_proc_root, &pvc_seq_ops,
389 			sizeof(struct vcc_state), (void *)(uintptr_t)PF_ATMPVC);
390 	proc_create_seq_private("svc", 0444, atm_proc_root, &svc_seq_ops,
391 			sizeof(struct vcc_state), (void *)(uintptr_t)PF_ATMSVC);
392 	proc_create_seq_private("vc", 0444, atm_proc_root, &vcc_seq_ops,
393 			sizeof(struct vcc_state), NULL);
394 	return 0;
395 }
396 
atm_proc_exit(void)397 void atm_proc_exit(void)
398 {
399 	remove_proc_subtree("atm", init_net.proc_net);
400 }
401