xref: /linux/fs/nfsd/nfsctl.c (revision 14b42963f64b98ab61fa9723c03d71aa5ef4f862)
1 /*
2  * linux/fs/nfsd/nfsctl.c
3  *
4  * Syscall interface to knfsd.
5  *
6  * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
7  */
8 
9 #include <linux/module.h>
10 
11 #include <linux/linkage.h>
12 #include <linux/time.h>
13 #include <linux/errno.h>
14 #include <linux/fs.h>
15 #include <linux/fcntl.h>
16 #include <linux/net.h>
17 #include <linux/in.h>
18 #include <linux/syscalls.h>
19 #include <linux/unistd.h>
20 #include <linux/slab.h>
21 #include <linux/proc_fs.h>
22 #include <linux/seq_file.h>
23 #include <linux/pagemap.h>
24 #include <linux/init.h>
25 #include <linux/string.h>
26 
27 #include <linux/nfs.h>
28 #include <linux/nfsd_idmap.h>
29 #include <linux/sunrpc/svc.h>
30 #include <linux/nfsd/nfsd.h>
31 #include <linux/nfsd/cache.h>
32 #include <linux/nfsd/xdr.h>
33 #include <linux/nfsd/syscall.h>
34 #include <linux/nfsd/interface.h>
35 
36 #include <asm/uaccess.h>
37 
38 unsigned int nfsd_versbits = ~0;
39 
40 /*
41  *	We have a single directory with 9 nodes in it.
42  */
43 enum {
44 	NFSD_Root = 1,
45 	NFSD_Svc,
46 	NFSD_Add,
47 	NFSD_Del,
48 	NFSD_Export,
49 	NFSD_Unexport,
50 	NFSD_Getfd,
51 	NFSD_Getfs,
52 	NFSD_List,
53 	NFSD_Fh,
54 	NFSD_Threads,
55 	NFSD_Versions,
56 	/*
57 	 * The below MUST come last.  Otherwise we leave a hole in nfsd_files[]
58 	 * with !CONFIG_NFSD_V4 and simple_fill_super() goes oops
59 	 */
60 #ifdef CONFIG_NFSD_V4
61 	NFSD_Leasetime,
62 	NFSD_RecoveryDir,
63 #endif
64 };
65 
66 /*
67  * write() for these nodes.
68  */
69 static ssize_t write_svc(struct file *file, char *buf, size_t size);
70 static ssize_t write_add(struct file *file, char *buf, size_t size);
71 static ssize_t write_del(struct file *file, char *buf, size_t size);
72 static ssize_t write_export(struct file *file, char *buf, size_t size);
73 static ssize_t write_unexport(struct file *file, char *buf, size_t size);
74 static ssize_t write_getfd(struct file *file, char *buf, size_t size);
75 static ssize_t write_getfs(struct file *file, char *buf, size_t size);
76 static ssize_t write_filehandle(struct file *file, char *buf, size_t size);
77 static ssize_t write_threads(struct file *file, char *buf, size_t size);
78 static ssize_t write_versions(struct file *file, char *buf, size_t size);
79 #ifdef CONFIG_NFSD_V4
80 static ssize_t write_leasetime(struct file *file, char *buf, size_t size);
81 static ssize_t write_recoverydir(struct file *file, char *buf, size_t size);
82 #endif
83 
84 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
85 	[NFSD_Svc] = write_svc,
86 	[NFSD_Add] = write_add,
87 	[NFSD_Del] = write_del,
88 	[NFSD_Export] = write_export,
89 	[NFSD_Unexport] = write_unexport,
90 	[NFSD_Getfd] = write_getfd,
91 	[NFSD_Getfs] = write_getfs,
92 	[NFSD_Fh] = write_filehandle,
93 	[NFSD_Threads] = write_threads,
94 	[NFSD_Versions] = write_versions,
95 #ifdef CONFIG_NFSD_V4
96 	[NFSD_Leasetime] = write_leasetime,
97 	[NFSD_RecoveryDir] = write_recoverydir,
98 #endif
99 };
100 
101 static ssize_t nfsctl_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
102 {
103 	ino_t ino =  file->f_dentry->d_inode->i_ino;
104 	char *data;
105 	ssize_t rv;
106 
107 	if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
108 		return -EINVAL;
109 
110 	data = simple_transaction_get(file, buf, size);
111 	if (IS_ERR(data))
112 		return PTR_ERR(data);
113 
114 	rv =  write_op[ino](file, data, size);
115 	if (rv>0) {
116 		simple_transaction_set(file, rv);
117 		rv = size;
118 	}
119 	return rv;
120 }
121 
122 static ssize_t nfsctl_transaction_read(struct file *file, char __user *buf, size_t size, loff_t *pos)
123 {
124 	if (! file->private_data) {
125 		/* An attempt to read a transaction file without writing
126 		 * causes a 0-byte write so that the file can return
127 		 * state information
128 		 */
129 		ssize_t rv = nfsctl_transaction_write(file, buf, 0, pos);
130 		if (rv < 0)
131 			return rv;
132 	}
133 	return simple_transaction_read(file, buf, size, pos);
134 }
135 
136 static const struct file_operations transaction_ops = {
137 	.write		= nfsctl_transaction_write,
138 	.read		= nfsctl_transaction_read,
139 	.release	= simple_transaction_release,
140 };
141 
142 extern struct seq_operations nfs_exports_op;
143 static int exports_open(struct inode *inode, struct file *file)
144 {
145 	return seq_open(file, &nfs_exports_op);
146 }
147 
148 static const struct file_operations exports_operations = {
149 	.open		= exports_open,
150 	.read		= seq_read,
151 	.llseek		= seq_lseek,
152 	.release	= seq_release,
153 };
154 
155 /*----------------------------------------------------------------------------*/
156 /*
157  * payload - write methods
158  * If the method has a response, the response should be put in buf,
159  * and the length returned.  Otherwise return 0 or and -error.
160  */
161 
162 static ssize_t write_svc(struct file *file, char *buf, size_t size)
163 {
164 	struct nfsctl_svc *data;
165 	if (size < sizeof(*data))
166 		return -EINVAL;
167 	data = (struct nfsctl_svc*) buf;
168 	return nfsd_svc(data->svc_port, data->svc_nthreads);
169 }
170 
171 static ssize_t write_add(struct file *file, char *buf, size_t size)
172 {
173 	struct nfsctl_client *data;
174 	if (size < sizeof(*data))
175 		return -EINVAL;
176 	data = (struct nfsctl_client *)buf;
177 	return exp_addclient(data);
178 }
179 
180 static ssize_t write_del(struct file *file, char *buf, size_t size)
181 {
182 	struct nfsctl_client *data;
183 	if (size < sizeof(*data))
184 		return -EINVAL;
185 	data = (struct nfsctl_client *)buf;
186 	return exp_delclient(data);
187 }
188 
189 static ssize_t write_export(struct file *file, char *buf, size_t size)
190 {
191 	struct nfsctl_export *data;
192 	if (size < sizeof(*data))
193 		return -EINVAL;
194 	data = (struct nfsctl_export*)buf;
195 	return exp_export(data);
196 }
197 
198 static ssize_t write_unexport(struct file *file, char *buf, size_t size)
199 {
200 	struct nfsctl_export *data;
201 
202 	if (size < sizeof(*data))
203 		return -EINVAL;
204 	data = (struct nfsctl_export*)buf;
205 	return exp_unexport(data);
206 }
207 
208 static ssize_t write_getfs(struct file *file, char *buf, size_t size)
209 {
210 	struct nfsctl_fsparm *data;
211 	struct sockaddr_in *sin;
212 	struct auth_domain *clp;
213 	int err = 0;
214 	struct knfsd_fh *res;
215 
216 	if (size < sizeof(*data))
217 		return -EINVAL;
218 	data = (struct nfsctl_fsparm*)buf;
219 	err = -EPROTONOSUPPORT;
220 	if (data->gd_addr.sa_family != AF_INET)
221 		goto out;
222 	sin = (struct sockaddr_in *)&data->gd_addr;
223 	if (data->gd_maxlen > NFS3_FHSIZE)
224 		data->gd_maxlen = NFS3_FHSIZE;
225 
226 	res = (struct knfsd_fh*)buf;
227 
228 	exp_readlock();
229 	if (!(clp = auth_unix_lookup(sin->sin_addr)))
230 		err = -EPERM;
231 	else {
232 		err = exp_rootfh(clp, data->gd_path, res, data->gd_maxlen);
233 		auth_domain_put(clp);
234 	}
235 	exp_readunlock();
236 	if (err == 0)
237 		err = res->fh_size + (int)&((struct knfsd_fh*)0)->fh_base;
238  out:
239 	return err;
240 }
241 
242 static ssize_t write_getfd(struct file *file, char *buf, size_t size)
243 {
244 	struct nfsctl_fdparm *data;
245 	struct sockaddr_in *sin;
246 	struct auth_domain *clp;
247 	int err = 0;
248 	struct knfsd_fh fh;
249 	char *res;
250 
251 	if (size < sizeof(*data))
252 		return -EINVAL;
253 	data = (struct nfsctl_fdparm*)buf;
254 	err = -EPROTONOSUPPORT;
255 	if (data->gd_addr.sa_family != AF_INET)
256 		goto out;
257 	err = -EINVAL;
258 	if (data->gd_version < 2 || data->gd_version > NFSSVC_MAXVERS)
259 		goto out;
260 
261 	res = buf;
262 	sin = (struct sockaddr_in *)&data->gd_addr;
263 	exp_readlock();
264 	if (!(clp = auth_unix_lookup(sin->sin_addr)))
265 		err = -EPERM;
266 	else {
267 		err = exp_rootfh(clp, data->gd_path, &fh, NFS_FHSIZE);
268 		auth_domain_put(clp);
269 	}
270 	exp_readunlock();
271 
272 	if (err == 0) {
273 		memset(res,0, NFS_FHSIZE);
274 		memcpy(res, &fh.fh_base, fh.fh_size);
275 		err = NFS_FHSIZE;
276 	}
277  out:
278 	return err;
279 }
280 
281 static ssize_t write_filehandle(struct file *file, char *buf, size_t size)
282 {
283 	/* request is:
284 	 *   domain path maxsize
285 	 * response is
286 	 *   filehandle
287 	 *
288 	 * qword quoting is used, so filehandle will be \x....
289 	 */
290 	char *dname, *path;
291 	int maxsize;
292 	char *mesg = buf;
293 	int len;
294 	struct auth_domain *dom;
295 	struct knfsd_fh fh;
296 
297 	if (buf[size-1] != '\n')
298 		return -EINVAL;
299 	buf[size-1] = 0;
300 
301 	dname = mesg;
302 	len = qword_get(&mesg, dname, size);
303 	if (len <= 0) return -EINVAL;
304 
305 	path = dname+len+1;
306 	len = qword_get(&mesg, path, size);
307 	if (len <= 0) return -EINVAL;
308 
309 	len = get_int(&mesg, &maxsize);
310 	if (len)
311 		return len;
312 
313 	if (maxsize < NFS_FHSIZE)
314 		return -EINVAL;
315 	if (maxsize > NFS3_FHSIZE)
316 		maxsize = NFS3_FHSIZE;
317 
318 	if (qword_get(&mesg, mesg, size)>0)
319 		return -EINVAL;
320 
321 	/* we have all the words, they are in buf.. */
322 	dom = unix_domain_find(dname);
323 	if (!dom)
324 		return -ENOMEM;
325 
326 	len = exp_rootfh(dom, path, &fh,  maxsize);
327 	auth_domain_put(dom);
328 	if (len)
329 		return len;
330 
331 	mesg = buf; len = SIMPLE_TRANSACTION_LIMIT;
332 	qword_addhex(&mesg, &len, (char*)&fh.fh_base, fh.fh_size);
333 	mesg[-1] = '\n';
334 	return mesg - buf;
335 }
336 
337 extern int nfsd_nrthreads(void);
338 
339 static ssize_t write_threads(struct file *file, char *buf, size_t size)
340 {
341 	/* if size > 0, look for a number of threads and call nfsd_svc
342 	 * then write out number of threads as reply
343 	 */
344 	char *mesg = buf;
345 	int rv;
346 	if (size > 0) {
347 		int newthreads;
348 		rv = get_int(&mesg, &newthreads);
349 		if (rv)
350 			return rv;
351 		if (newthreads <0)
352 			return -EINVAL;
353 		rv = nfsd_svc(2049, newthreads);
354 		if (rv)
355 			return rv;
356 	}
357 	sprintf(buf, "%d\n", nfsd_nrthreads());
358 	return strlen(buf);
359 }
360 
361 static ssize_t write_versions(struct file *file, char *buf, size_t size)
362 {
363 	/*
364 	 * Format:
365 	 *   [-/+]vers [-/+]vers ...
366 	 */
367 	char *mesg = buf;
368 	char *vers, sign;
369 	int len, num;
370 	ssize_t tlen = 0;
371 	char *sep;
372 
373 	if (size>0) {
374 		if (nfsd_serv)
375 			return -EBUSY;
376 		if (buf[size-1] != '\n')
377 			return -EINVAL;
378 		buf[size-1] = 0;
379 
380 		vers = mesg;
381 		len = qword_get(&mesg, vers, size);
382 		if (len <= 0) return -EINVAL;
383 		do {
384 			sign = *vers;
385 			if (sign == '+' || sign == '-')
386 				num = simple_strtol((vers+1), NULL, 0);
387 			else
388 				num = simple_strtol(vers, NULL, 0);
389 			switch(num) {
390 			case 2:
391 			case 3:
392 			case 4:
393 				if (sign != '-')
394 					NFSCTL_VERSET(nfsd_versbits, num);
395 				else
396 					NFSCTL_VERUNSET(nfsd_versbits, num);
397 				break;
398 			default:
399 				return -EINVAL;
400 			}
401 			vers += len + 1;
402 			tlen += len;
403 		} while ((len = qword_get(&mesg, vers, size)) > 0);
404 		/* If all get turned off, turn them back on, as
405 		 * having no versions is BAD
406 		 */
407 		if ((nfsd_versbits & NFSCTL_VERALL)==0)
408 			nfsd_versbits = NFSCTL_VERALL;
409 	}
410 	/* Now write current state into reply buffer */
411 	len = 0;
412 	sep = "";
413 	for (num=2 ; num <= 4 ; num++)
414 		if (NFSCTL_VERISSET(NFSCTL_VERALL, num)) {
415 			len += sprintf(buf+len, "%s%c%d", sep,
416 				       NFSCTL_VERISSET(nfsd_versbits, num)?'+':'-',
417 				       num);
418 			sep = " ";
419 		}
420 	len += sprintf(buf+len, "\n");
421 	return len;
422 }
423 
424 #ifdef CONFIG_NFSD_V4
425 extern time_t nfs4_leasetime(void);
426 
427 static ssize_t write_leasetime(struct file *file, char *buf, size_t size)
428 {
429 	/* if size > 10 seconds, call
430 	 * nfs4_reset_lease() then write out the new lease (seconds) as reply
431 	 */
432 	char *mesg = buf;
433 	int rv;
434 
435 	if (size > 0) {
436 		int lease;
437 		rv = get_int(&mesg, &lease);
438 		if (rv)
439 			return rv;
440 		if (lease < 10 || lease > 3600)
441 			return -EINVAL;
442 		nfs4_reset_lease(lease);
443 	}
444 	sprintf(buf, "%ld\n", nfs4_lease_time());
445 	return strlen(buf);
446 }
447 
448 static ssize_t write_recoverydir(struct file *file, char *buf, size_t size)
449 {
450 	char *mesg = buf;
451 	char *recdir;
452 	int len, status;
453 
454 	if (size > PATH_MAX || buf[size-1] != '\n')
455 		return -EINVAL;
456 	buf[size-1] = 0;
457 
458 	recdir = mesg;
459 	len = qword_get(&mesg, recdir, size);
460 	if (len <= 0)
461 		return -EINVAL;
462 
463 	status = nfs4_reset_recoverydir(recdir);
464 	return strlen(buf);
465 }
466 #endif
467 
468 /*----------------------------------------------------------------------------*/
469 /*
470  *	populating the filesystem.
471  */
472 
473 static int nfsd_fill_super(struct super_block * sb, void * data, int silent)
474 {
475 	static struct tree_descr nfsd_files[] = {
476 		[NFSD_Svc] = {".svc", &transaction_ops, S_IWUSR},
477 		[NFSD_Add] = {".add", &transaction_ops, S_IWUSR},
478 		[NFSD_Del] = {".del", &transaction_ops, S_IWUSR},
479 		[NFSD_Export] = {".export", &transaction_ops, S_IWUSR},
480 		[NFSD_Unexport] = {".unexport", &transaction_ops, S_IWUSR},
481 		[NFSD_Getfd] = {".getfd", &transaction_ops, S_IWUSR|S_IRUSR},
482 		[NFSD_Getfs] = {".getfs", &transaction_ops, S_IWUSR|S_IRUSR},
483 		[NFSD_List] = {"exports", &exports_operations, S_IRUGO},
484 		[NFSD_Fh] = {"filehandle", &transaction_ops, S_IWUSR|S_IRUSR},
485 		[NFSD_Threads] = {"threads", &transaction_ops, S_IWUSR|S_IRUSR},
486 		[NFSD_Versions] = {"versions", &transaction_ops, S_IWUSR|S_IRUSR},
487 #ifdef CONFIG_NFSD_V4
488 		[NFSD_Leasetime] = {"nfsv4leasetime", &transaction_ops, S_IWUSR|S_IRUSR},
489 		[NFSD_RecoveryDir] = {"nfsv4recoverydir", &transaction_ops, S_IWUSR|S_IRUSR},
490 #endif
491 		/* last one */ {""}
492 	};
493 	return simple_fill_super(sb, 0x6e667364, nfsd_files);
494 }
495 
496 static int nfsd_get_sb(struct file_system_type *fs_type,
497 	int flags, const char *dev_name, void *data, struct vfsmount *mnt)
498 {
499 	return get_sb_single(fs_type, flags, data, nfsd_fill_super, mnt);
500 }
501 
502 static struct file_system_type nfsd_fs_type = {
503 	.owner		= THIS_MODULE,
504 	.name		= "nfsd",
505 	.get_sb		= nfsd_get_sb,
506 	.kill_sb	= kill_litter_super,
507 };
508 
509 static int __init init_nfsd(void)
510 {
511 	int retval;
512 	printk(KERN_INFO "Installing knfsd (copyright (C) 1996 okir@monad.swb.de).\n");
513 
514 	nfsd_stat_init();	/* Statistics */
515 	nfsd_cache_init();	/* RPC reply cache */
516 	nfsd_export_init();	/* Exports table */
517 	nfsd_lockd_init();	/* lockd->nfsd callbacks */
518 	nfs4_state_init();	/* NFSv4 locking state */
519 	nfsd_idmap_init();      /* Name to ID mapping */
520 	if (proc_mkdir("fs/nfs", NULL)) {
521 		struct proc_dir_entry *entry;
522 		entry = create_proc_entry("fs/nfs/exports", 0, NULL);
523 		if (entry)
524 			entry->proc_fops =  &exports_operations;
525 	}
526 	retval = register_filesystem(&nfsd_fs_type);
527 	if (retval) {
528 		nfsd_export_shutdown();
529 		nfsd_cache_shutdown();
530 		remove_proc_entry("fs/nfs/exports", NULL);
531 		remove_proc_entry("fs/nfs", NULL);
532 		nfsd_stat_shutdown();
533 		nfsd_lockd_shutdown();
534 	}
535 	return retval;
536 }
537 
538 static void __exit exit_nfsd(void)
539 {
540 	nfsd_export_shutdown();
541 	nfsd_cache_shutdown();
542 	remove_proc_entry("fs/nfs/exports", NULL);
543 	remove_proc_entry("fs/nfs", NULL);
544 	nfsd_stat_shutdown();
545 	nfsd_lockd_shutdown();
546 	nfsd_idmap_shutdown();
547 	unregister_filesystem(&nfsd_fs_type);
548 }
549 
550 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
551 MODULE_LICENSE("GPL");
552 module_init(init_nfsd)
553 module_exit(exit_nfsd)
554