xref: /openbmc/linux/fs/nfsd/nfsctl.c (revision 87c2ce3b)
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/config.h>
10 #include <linux/module.h>
11 
12 #include <linux/linkage.h>
13 #include <linux/time.h>
14 #include <linux/errno.h>
15 #include <linux/fs.h>
16 #include <linux/fcntl.h>
17 #include <linux/net.h>
18 #include <linux/in.h>
19 #include <linux/syscalls.h>
20 #include <linux/unistd.h>
21 #include <linux/slab.h>
22 #include <linux/proc_fs.h>
23 #include <linux/seq_file.h>
24 #include <linux/pagemap.h>
25 #include <linux/init.h>
26 #include <linux/string.h>
27 
28 #include <linux/nfs.h>
29 #include <linux/nfsd_idmap.h>
30 #include <linux/sunrpc/svc.h>
31 #include <linux/nfsd/nfsd.h>
32 #include <linux/nfsd/cache.h>
33 #include <linux/nfsd/xdr.h>
34 #include <linux/nfsd/syscall.h>
35 #include <linux/nfsd/interface.h>
36 
37 #include <asm/uaccess.h>
38 
39 unsigned int nfsd_versbits = ~0;
40 
41 /*
42  *	We have a single directory with 9 nodes in it.
43  */
44 enum {
45 	NFSD_Root = 1,
46 	NFSD_Svc,
47 	NFSD_Add,
48 	NFSD_Del,
49 	NFSD_Export,
50 	NFSD_Unexport,
51 	NFSD_Getfd,
52 	NFSD_Getfs,
53 	NFSD_List,
54 	NFSD_Fh,
55 	NFSD_Threads,
56 	NFSD_Versions,
57 	/*
58 	 * The below MUST come last.  Otherwise we leave a hole in nfsd_files[]
59 	 * with !CONFIG_NFSD_V4 and simple_fill_super() goes oops
60 	 */
61 #ifdef CONFIG_NFSD_V4
62 	NFSD_Leasetime,
63 	NFSD_RecoveryDir,
64 #endif
65 };
66 
67 /*
68  * write() for these nodes.
69  */
70 static ssize_t write_svc(struct file *file, char *buf, size_t size);
71 static ssize_t write_add(struct file *file, char *buf, size_t size);
72 static ssize_t write_del(struct file *file, char *buf, size_t size);
73 static ssize_t write_export(struct file *file, char *buf, size_t size);
74 static ssize_t write_unexport(struct file *file, char *buf, size_t size);
75 static ssize_t write_getfd(struct file *file, char *buf, size_t size);
76 static ssize_t write_getfs(struct file *file, char *buf, size_t size);
77 static ssize_t write_filehandle(struct file *file, char *buf, size_t size);
78 static ssize_t write_threads(struct file *file, char *buf, size_t size);
79 static ssize_t write_versions(struct file *file, char *buf, size_t size);
80 #ifdef CONFIG_NFSD_V4
81 static ssize_t write_leasetime(struct file *file, char *buf, size_t size);
82 static ssize_t write_recoverydir(struct file *file, char *buf, size_t size);
83 #endif
84 
85 static ssize_t (*write_op[])(struct file *, char *, size_t) = {
86 	[NFSD_Svc] = write_svc,
87 	[NFSD_Add] = write_add,
88 	[NFSD_Del] = write_del,
89 	[NFSD_Export] = write_export,
90 	[NFSD_Unexport] = write_unexport,
91 	[NFSD_Getfd] = write_getfd,
92 	[NFSD_Getfs] = write_getfs,
93 	[NFSD_Fh] = write_filehandle,
94 	[NFSD_Threads] = write_threads,
95 	[NFSD_Versions] = write_versions,
96 #ifdef CONFIG_NFSD_V4
97 	[NFSD_Leasetime] = write_leasetime,
98 	[NFSD_RecoveryDir] = write_recoverydir,
99 #endif
100 };
101 
102 static ssize_t nfsctl_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
103 {
104 	ino_t ino =  file->f_dentry->d_inode->i_ino;
105 	char *data;
106 	ssize_t rv;
107 
108 	if (ino >= sizeof(write_op)/sizeof(write_op[0]) || !write_op[ino])
109 		return -EINVAL;
110 
111 	data = simple_transaction_get(file, buf, size);
112 	if (IS_ERR(data))
113 		return PTR_ERR(data);
114 
115 	rv =  write_op[ino](file, data, size);
116 	if (rv>0) {
117 		simple_transaction_set(file, rv);
118 		rv = size;
119 	}
120 	return rv;
121 }
122 
123 static ssize_t nfsctl_transaction_read(struct file *file, char __user *buf, size_t size, loff_t *pos)
124 {
125 	if (! file->private_data) {
126 		/* An attempt to read a transaction file without writing
127 		 * causes a 0-byte write so that the file can return
128 		 * state information
129 		 */
130 		ssize_t rv = nfsctl_transaction_write(file, buf, 0, pos);
131 		if (rv < 0)
132 			return rv;
133 	}
134 	return simple_transaction_read(file, buf, size, pos);
135 }
136 
137 static struct file_operations transaction_ops = {
138 	.write		= nfsctl_transaction_write,
139 	.read		= nfsctl_transaction_read,
140 	.release	= simple_transaction_release,
141 };
142 
143 extern struct seq_operations nfs_exports_op;
144 static int exports_open(struct inode *inode, struct file *file)
145 {
146 	return seq_open(file, &nfs_exports_op);
147 }
148 
149 static struct file_operations exports_operations = {
150 	.open		= exports_open,
151 	.read		= seq_read,
152 	.llseek		= seq_lseek,
153 	.release	= seq_release,
154 };
155 
156 /*----------------------------------------------------------------------------*/
157 /*
158  * payload - write methods
159  * If the method has a response, the response should be put in buf,
160  * and the length returned.  Otherwise return 0 or and -error.
161  */
162 
163 static ssize_t write_svc(struct file *file, char *buf, size_t size)
164 {
165 	struct nfsctl_svc *data;
166 	if (size < sizeof(*data))
167 		return -EINVAL;
168 	data = (struct nfsctl_svc*) buf;
169 	return nfsd_svc(data->svc_port, data->svc_nthreads);
170 }
171 
172 static ssize_t write_add(struct file *file, char *buf, size_t size)
173 {
174 	struct nfsctl_client *data;
175 	if (size < sizeof(*data))
176 		return -EINVAL;
177 	data = (struct nfsctl_client *)buf;
178 	return exp_addclient(data);
179 }
180 
181 static ssize_t write_del(struct file *file, char *buf, size_t size)
182 {
183 	struct nfsctl_client *data;
184 	if (size < sizeof(*data))
185 		return -EINVAL;
186 	data = (struct nfsctl_client *)buf;
187 	return exp_delclient(data);
188 }
189 
190 static ssize_t write_export(struct file *file, char *buf, size_t size)
191 {
192 	struct nfsctl_export *data;
193 	if (size < sizeof(*data))
194 		return -EINVAL;
195 	data = (struct nfsctl_export*)buf;
196 	return exp_export(data);
197 }
198 
199 static ssize_t write_unexport(struct file *file, char *buf, size_t size)
200 {
201 	struct nfsctl_export *data;
202 
203 	if (size < sizeof(*data))
204 		return -EINVAL;
205 	data = (struct nfsctl_export*)buf;
206 	return exp_unexport(data);
207 }
208 
209 static ssize_t write_getfs(struct file *file, char *buf, size_t size)
210 {
211 	struct nfsctl_fsparm *data;
212 	struct sockaddr_in *sin;
213 	struct auth_domain *clp;
214 	int err = 0;
215 	struct knfsd_fh *res;
216 
217 	if (size < sizeof(*data))
218 		return -EINVAL;
219 	data = (struct nfsctl_fsparm*)buf;
220 	err = -EPROTONOSUPPORT;
221 	if (data->gd_addr.sa_family != AF_INET)
222 		goto out;
223 	sin = (struct sockaddr_in *)&data->gd_addr;
224 	if (data->gd_maxlen > NFS3_FHSIZE)
225 		data->gd_maxlen = NFS3_FHSIZE;
226 
227 	res = (struct knfsd_fh*)buf;
228 
229 	exp_readlock();
230 	if (!(clp = auth_unix_lookup(sin->sin_addr)))
231 		err = -EPERM;
232 	else {
233 		err = exp_rootfh(clp, data->gd_path, res, data->gd_maxlen);
234 		auth_domain_put(clp);
235 	}
236 	exp_readunlock();
237 	if (err == 0)
238 		err = res->fh_size + (int)&((struct knfsd_fh*)0)->fh_base;
239  out:
240 	return err;
241 }
242 
243 static ssize_t write_getfd(struct file *file, char *buf, size_t size)
244 {
245 	struct nfsctl_fdparm *data;
246 	struct sockaddr_in *sin;
247 	struct auth_domain *clp;
248 	int err = 0;
249 	struct knfsd_fh fh;
250 	char *res;
251 
252 	if (size < sizeof(*data))
253 		return -EINVAL;
254 	data = (struct nfsctl_fdparm*)buf;
255 	err = -EPROTONOSUPPORT;
256 	if (data->gd_addr.sa_family != AF_INET)
257 		goto out;
258 	err = -EINVAL;
259 	if (data->gd_version < 2 || data->gd_version > NFSSVC_MAXVERS)
260 		goto out;
261 
262 	res = buf;
263 	sin = (struct sockaddr_in *)&data->gd_addr;
264 	exp_readlock();
265 	if (!(clp = auth_unix_lookup(sin->sin_addr)))
266 		err = -EPERM;
267 	else {
268 		err = exp_rootfh(clp, data->gd_path, &fh, NFS_FHSIZE);
269 		auth_domain_put(clp);
270 	}
271 	exp_readunlock();
272 
273 	if (err == 0) {
274 		memset(res,0, NFS_FHSIZE);
275 		memcpy(res, &fh.fh_base, fh.fh_size);
276 		err = NFS_FHSIZE;
277 	}
278  out:
279 	return err;
280 }
281 
282 static ssize_t write_filehandle(struct file *file, char *buf, size_t size)
283 {
284 	/* request is:
285 	 *   domain path maxsize
286 	 * response is
287 	 *   filehandle
288 	 *
289 	 * qword quoting is used, so filehandle will be \x....
290 	 */
291 	char *dname, *path;
292 	int maxsize;
293 	char *mesg = buf;
294 	int len;
295 	struct auth_domain *dom;
296 	struct knfsd_fh fh;
297 
298 	if (buf[size-1] != '\n')
299 		return -EINVAL;
300 	buf[size-1] = 0;
301 
302 	dname = mesg;
303 	len = qword_get(&mesg, dname, size);
304 	if (len <= 0) return -EINVAL;
305 
306 	path = dname+len+1;
307 	len = qword_get(&mesg, path, size);
308 	if (len <= 0) return -EINVAL;
309 
310 	len = get_int(&mesg, &maxsize);
311 	if (len)
312 		return len;
313 
314 	if (maxsize < NFS_FHSIZE)
315 		return -EINVAL;
316 	if (maxsize > NFS3_FHSIZE)
317 		maxsize = NFS3_FHSIZE;
318 
319 	if (qword_get(&mesg, mesg, size)>0)
320 		return -EINVAL;
321 
322 	/* we have all the words, they are in buf.. */
323 	dom = unix_domain_find(dname);
324 	if (!dom)
325 		return -ENOMEM;
326 
327 	len = exp_rootfh(dom, path, &fh,  maxsize);
328 	auth_domain_put(dom);
329 	if (len)
330 		return len;
331 
332 	mesg = buf; len = SIMPLE_TRANSACTION_LIMIT;
333 	qword_addhex(&mesg, &len, (char*)&fh.fh_base, fh.fh_size);
334 	mesg[-1] = '\n';
335 	return mesg - buf;
336 }
337 
338 extern int nfsd_nrthreads(void);
339 
340 static ssize_t write_threads(struct file *file, char *buf, size_t size)
341 {
342 	/* if size > 0, look for a number of threads and call nfsd_svc
343 	 * then write out number of threads as reply
344 	 */
345 	char *mesg = buf;
346 	int rv;
347 	if (size > 0) {
348 		int newthreads;
349 		rv = get_int(&mesg, &newthreads);
350 		if (rv)
351 			return rv;
352 		if (newthreads <0)
353 			return -EINVAL;
354 		rv = nfsd_svc(2049, newthreads);
355 		if (rv)
356 			return rv;
357 	}
358 	sprintf(buf, "%d\n", nfsd_nrthreads());
359 	return strlen(buf);
360 }
361 
362 static ssize_t write_versions(struct file *file, char *buf, size_t size)
363 {
364 	/*
365 	 * Format:
366 	 *   [-/+]vers [-/+]vers ...
367 	 */
368 	char *mesg = buf;
369 	char *vers, sign;
370 	int len, num;
371 	ssize_t tlen = 0;
372 	char *sep;
373 
374 	if (size>0) {
375 		if (nfsd_serv)
376 			return -EBUSY;
377 		if (buf[size-1] != '\n')
378 			return -EINVAL;
379 		buf[size-1] = 0;
380 
381 		vers = mesg;
382 		len = qword_get(&mesg, vers, size);
383 		if (len <= 0) return -EINVAL;
384 		do {
385 			sign = *vers;
386 			if (sign == '+' || sign == '-')
387 				num = simple_strtol((vers+1), NULL, 0);
388 			else
389 				num = simple_strtol(vers, NULL, 0);
390 			switch(num) {
391 			case 2:
392 			case 3:
393 			case 4:
394 				if (sign != '-')
395 					NFSCTL_VERSET(nfsd_versbits, num);
396 				else
397 					NFSCTL_VERUNSET(nfsd_versbits, num);
398 				break;
399 			default:
400 				return -EINVAL;
401 			}
402 			vers += len + 1;
403 			tlen += len;
404 		} while ((len = qword_get(&mesg, vers, size)) > 0);
405 		/* If all get turned off, turn them back on, as
406 		 * having no versions is BAD
407 		 */
408 		if ((nfsd_versbits & NFSCTL_VERALL)==0)
409 			nfsd_versbits = NFSCTL_VERALL;
410 	}
411 	/* Now write current state into reply buffer */
412 	len = 0;
413 	sep = "";
414 	for (num=2 ; num <= 4 ; num++)
415 		if (NFSCTL_VERISSET(NFSCTL_VERALL, num)) {
416 			len += sprintf(buf+len, "%s%c%d", sep,
417 				       NFSCTL_VERISSET(nfsd_versbits, num)?'+':'-',
418 				       num);
419 			sep = " ";
420 		}
421 	len += sprintf(buf+len, "\n");
422 	return len;
423 }
424 
425 #ifdef CONFIG_NFSD_V4
426 extern time_t nfs4_leasetime(void);
427 
428 static ssize_t write_leasetime(struct file *file, char *buf, size_t size)
429 {
430 	/* if size > 10 seconds, call
431 	 * nfs4_reset_lease() then write out the new lease (seconds) as reply
432 	 */
433 	char *mesg = buf;
434 	int rv;
435 
436 	if (size > 0) {
437 		int lease;
438 		rv = get_int(&mesg, &lease);
439 		if (rv)
440 			return rv;
441 		if (lease < 10 || lease > 3600)
442 			return -EINVAL;
443 		nfs4_reset_lease(lease);
444 	}
445 	sprintf(buf, "%ld\n", nfs4_lease_time());
446 	return strlen(buf);
447 }
448 
449 static ssize_t write_recoverydir(struct file *file, char *buf, size_t size)
450 {
451 	char *mesg = buf;
452 	char *recdir;
453 	int len, status;
454 
455 	if (size > PATH_MAX || buf[size-1] != '\n')
456 		return -EINVAL;
457 	buf[size-1] = 0;
458 
459 	recdir = mesg;
460 	len = qword_get(&mesg, recdir, size);
461 	if (len <= 0)
462 		return -EINVAL;
463 
464 	status = nfs4_reset_recoverydir(recdir);
465 	return strlen(buf);
466 }
467 #endif
468 
469 /*----------------------------------------------------------------------------*/
470 /*
471  *	populating the filesystem.
472  */
473 
474 static int nfsd_fill_super(struct super_block * sb, void * data, int silent)
475 {
476 	static struct tree_descr nfsd_files[] = {
477 		[NFSD_Svc] = {".svc", &transaction_ops, S_IWUSR},
478 		[NFSD_Add] = {".add", &transaction_ops, S_IWUSR},
479 		[NFSD_Del] = {".del", &transaction_ops, S_IWUSR},
480 		[NFSD_Export] = {".export", &transaction_ops, S_IWUSR},
481 		[NFSD_Unexport] = {".unexport", &transaction_ops, S_IWUSR},
482 		[NFSD_Getfd] = {".getfd", &transaction_ops, S_IWUSR|S_IRUSR},
483 		[NFSD_Getfs] = {".getfs", &transaction_ops, S_IWUSR|S_IRUSR},
484 		[NFSD_List] = {"exports", &exports_operations, S_IRUGO},
485 		[NFSD_Fh] = {"filehandle", &transaction_ops, S_IWUSR|S_IRUSR},
486 		[NFSD_Threads] = {"threads", &transaction_ops, S_IWUSR|S_IRUSR},
487 		[NFSD_Versions] = {"versions", &transaction_ops, S_IWUSR|S_IRUSR},
488 #ifdef CONFIG_NFSD_V4
489 		[NFSD_Leasetime] = {"nfsv4leasetime", &transaction_ops, S_IWUSR|S_IRUSR},
490 		[NFSD_RecoveryDir] = {"nfsv4recoverydir", &transaction_ops, S_IWUSR|S_IRUSR},
491 #endif
492 		/* last one */ {""}
493 	};
494 	return simple_fill_super(sb, 0x6e667364, nfsd_files);
495 }
496 
497 static struct super_block *nfsd_get_sb(struct file_system_type *fs_type,
498 	int flags, const char *dev_name, void *data)
499 {
500 	return get_sb_single(fs_type, flags, data, nfsd_fill_super);
501 }
502 
503 static struct file_system_type nfsd_fs_type = {
504 	.owner		= THIS_MODULE,
505 	.name		= "nfsd",
506 	.get_sb		= nfsd_get_sb,
507 	.kill_sb	= kill_litter_super,
508 };
509 
510 static int __init init_nfsd(void)
511 {
512 	int retval;
513 	printk(KERN_INFO "Installing knfsd (copyright (C) 1996 okir@monad.swb.de).\n");
514 
515 	nfsd_stat_init();	/* Statistics */
516 	nfsd_cache_init();	/* RPC reply cache */
517 	nfsd_export_init();	/* Exports table */
518 	nfsd_lockd_init();	/* lockd->nfsd callbacks */
519 	nfs4_state_init();	/* NFSv4 locking state */
520 	nfsd_idmap_init();      /* Name to ID mapping */
521 	if (proc_mkdir("fs/nfs", NULL)) {
522 		struct proc_dir_entry *entry;
523 		entry = create_proc_entry("fs/nfs/exports", 0, NULL);
524 		if (entry)
525 			entry->proc_fops =  &exports_operations;
526 	}
527 	retval = register_filesystem(&nfsd_fs_type);
528 	if (retval) {
529 		nfsd_export_shutdown();
530 		nfsd_cache_shutdown();
531 		remove_proc_entry("fs/nfs/exports", NULL);
532 		remove_proc_entry("fs/nfs", NULL);
533 		nfsd_stat_shutdown();
534 		nfsd_lockd_shutdown();
535 	}
536 	return retval;
537 }
538 
539 static void __exit exit_nfsd(void)
540 {
541 	nfsd_export_shutdown();
542 	nfsd_cache_shutdown();
543 	remove_proc_entry("fs/nfs/exports", NULL);
544 	remove_proc_entry("fs/nfs", NULL);
545 	nfsd_stat_shutdown();
546 	nfsd_lockd_shutdown();
547 	nfsd_idmap_shutdown();
548 	unregister_filesystem(&nfsd_fs_type);
549 }
550 
551 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
552 MODULE_LICENSE("GPL");
553 module_init(init_nfsd)
554 module_exit(exit_nfsd)
555