xref: /linux/fs/nfs/callback_xdr.c (revision 55d0969c451159cff86949b38c39171cab962069)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * linux/fs/nfs/callback_xdr.c
4  *
5  * Copyright (C) 2004 Trond Myklebust
6  *
7  * NFSv4 callback encode/decode procedures
8  */
9 #include <linux/kernel.h>
10 #include <linux/sunrpc/svc.h>
11 #include <linux/nfs4.h>
12 #include <linux/nfs_fs.h>
13 #include <linux/ratelimit.h>
14 #include <linux/printk.h>
15 #include <linux/slab.h>
16 #include <linux/sunrpc/bc_xprt.h>
17 #include "nfs4_fs.h"
18 #include "callback.h"
19 #include "internal.h"
20 #include "nfs4session.h"
21 #include "nfs4trace.h"
22 
23 #define CB_OP_TAGLEN_MAXSZ		(512)
24 #define CB_OP_HDR_RES_MAXSZ		(2 * 4) // opcode, status
25 #define CB_OP_GETATTR_BITMAP_MAXSZ	(4 * 4) // bitmap length, 3 bitmaps
26 #define CB_OP_GETATTR_RES_MAXSZ		(CB_OP_HDR_RES_MAXSZ + \
27 					 CB_OP_GETATTR_BITMAP_MAXSZ + \
28 					 /* change, size, atime, ctime,
29 					  * mtime, deleg_atime, deleg_mtime */\
30 					 (2 + 2 + 3 + 3 + 3 + 3 + 3) * 4)
31 #define CB_OP_RECALL_RES_MAXSZ		(CB_OP_HDR_RES_MAXSZ)
32 
33 #if defined(CONFIG_NFS_V4_1)
34 #define CB_OP_LAYOUTRECALL_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
35 #define CB_OP_DEVICENOTIFY_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
36 #define CB_OP_SEQUENCE_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ + \
37 					 NFS4_MAX_SESSIONID_LEN + \
38 					 (1 + 3) * 4) // seqid, 3 slotids
39 #define CB_OP_RECALLANY_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
40 #define CB_OP_RECALLSLOT_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
41 #define CB_OP_NOTIFY_LOCK_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
42 #endif /* CONFIG_NFS_V4_1 */
43 #ifdef CONFIG_NFS_V4_2
44 #define CB_OP_OFFLOAD_RES_MAXSZ		(CB_OP_HDR_RES_MAXSZ)
45 #endif /* CONFIG_NFS_V4_2 */
46 
47 #define NFSDBG_FACILITY NFSDBG_CALLBACK
48 
49 /* Internal error code */
50 #define NFS4ERR_RESOURCE_HDR	11050
51 
52 struct callback_op {
53 	__be32 (*process_op)(void *, void *, struct cb_process_state *);
54 	__be32 (*decode_args)(struct svc_rqst *, struct xdr_stream *, void *);
55 	__be32 (*encode_res)(struct svc_rqst *, struct xdr_stream *,
56 			const void *);
57 	long res_maxsize;
58 };
59 
60 static struct callback_op callback_ops[];
61 
62 static __be32 nfs4_callback_null(struct svc_rqst *rqstp)
63 {
64 	return htonl(NFS4_OK);
65 }
66 
67 /*
68  * svc_process_common() looks for an XDR encoder to know when
69  * not to drop a Reply.
70  */
71 static bool nfs4_encode_void(struct svc_rqst *rqstp, struct xdr_stream *xdr)
72 {
73 	return true;
74 }
75 
76 static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len,
77 		const char **str, size_t maxlen)
78 {
79 	ssize_t err;
80 
81 	err = xdr_stream_decode_opaque_inline(xdr, (void **)str, maxlen);
82 	if (err < 0)
83 		return cpu_to_be32(NFS4ERR_RESOURCE);
84 	*len = err;
85 	return 0;
86 }
87 
88 static __be32 decode_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
89 {
90 	__be32 *p;
91 
92 	p = xdr_inline_decode(xdr, 4);
93 	if (unlikely(p == NULL))
94 		return htonl(NFS4ERR_RESOURCE);
95 	fh->size = ntohl(*p);
96 	if (fh->size > NFS4_FHSIZE)
97 		return htonl(NFS4ERR_BADHANDLE);
98 	p = xdr_inline_decode(xdr, fh->size);
99 	if (unlikely(p == NULL))
100 		return htonl(NFS4ERR_RESOURCE);
101 	memcpy(&fh->data[0], p, fh->size);
102 	memset(&fh->data[fh->size], 0, sizeof(fh->data) - fh->size);
103 	return 0;
104 }
105 
106 static __be32 decode_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
107 {
108 	__be32 *p;
109 	unsigned int attrlen;
110 
111 	p = xdr_inline_decode(xdr, 4);
112 	if (unlikely(p == NULL))
113 		return htonl(NFS4ERR_RESOURCE);
114 	attrlen = ntohl(*p);
115 	p = xdr_inline_decode(xdr, attrlen << 2);
116 	if (unlikely(p == NULL))
117 		return htonl(NFS4ERR_RESOURCE);
118 	if (likely(attrlen > 0))
119 		bitmap[0] = ntohl(*p++);
120 	if (attrlen > 1)
121 		bitmap[1] = ntohl(*p++);
122 	if (attrlen > 2)
123 		bitmap[2] = ntohl(*p);
124 	return 0;
125 }
126 
127 static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
128 {
129 	__be32 *p;
130 
131 	p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
132 	if (unlikely(p == NULL))
133 		return htonl(NFS4ERR_RESOURCE);
134 	memcpy(stateid->data, p, NFS4_STATEID_SIZE);
135 	return 0;
136 }
137 
138 static __be32 decode_delegation_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
139 {
140 	stateid->type = NFS4_DELEGATION_STATEID_TYPE;
141 	return decode_stateid(xdr, stateid);
142 }
143 
144 static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
145 {
146 	__be32 *p;
147 	__be32 status;
148 
149 	status = decode_string(xdr, &hdr->taglen, &hdr->tag, CB_OP_TAGLEN_MAXSZ);
150 	if (unlikely(status != 0))
151 		return status;
152 	p = xdr_inline_decode(xdr, 12);
153 	if (unlikely(p == NULL))
154 		return htonl(NFS4ERR_RESOURCE);
155 	hdr->minorversion = ntohl(*p++);
156 	/* Check for minor version support */
157 	if (hdr->minorversion <= NFS4_MAX_MINOR_VERSION) {
158 		hdr->cb_ident = ntohl(*p++); /* ignored by v4.1 and v4.2 */
159 	} else {
160 		pr_warn_ratelimited("NFS: %s: NFSv4 server callback with "
161 			"illegal minor version %u!\n",
162 			__func__, hdr->minorversion);
163 		return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
164 	}
165 	hdr->nops = ntohl(*p);
166 	return 0;
167 }
168 
169 static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
170 {
171 	__be32 *p;
172 	p = xdr_inline_decode(xdr, 4);
173 	if (unlikely(p == NULL))
174 		return htonl(NFS4ERR_RESOURCE_HDR);
175 	*op = ntohl(*p);
176 	return 0;
177 }
178 
179 static __be32 decode_getattr_args(struct svc_rqst *rqstp,
180 		struct xdr_stream *xdr, void *argp)
181 {
182 	struct cb_getattrargs *args = argp;
183 	__be32 status;
184 
185 	status = decode_fh(xdr, &args->fh);
186 	if (unlikely(status != 0))
187 		return status;
188 	return decode_bitmap(xdr, args->bitmap);
189 }
190 
191 static __be32 decode_recall_args(struct svc_rqst *rqstp,
192 		struct xdr_stream *xdr, void *argp)
193 {
194 	struct cb_recallargs *args = argp;
195 	__be32 *p;
196 	__be32 status;
197 
198 	status = decode_delegation_stateid(xdr, &args->stateid);
199 	if (unlikely(status != 0))
200 		return status;
201 	p = xdr_inline_decode(xdr, 4);
202 	if (unlikely(p == NULL))
203 		return htonl(NFS4ERR_RESOURCE);
204 	args->truncate = ntohl(*p);
205 	return decode_fh(xdr, &args->fh);
206 }
207 
208 #if defined(CONFIG_NFS_V4_1)
209 static __be32 decode_layout_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
210 {
211 	stateid->type = NFS4_LAYOUT_STATEID_TYPE;
212 	return decode_stateid(xdr, stateid);
213 }
214 
215 static __be32 decode_layoutrecall_args(struct svc_rqst *rqstp,
216 				       struct xdr_stream *xdr, void *argp)
217 {
218 	struct cb_layoutrecallargs *args = argp;
219 	__be32 *p;
220 	__be32 status = 0;
221 	uint32_t iomode;
222 
223 	p = xdr_inline_decode(xdr, 4 * sizeof(uint32_t));
224 	if (unlikely(p == NULL))
225 		return htonl(NFS4ERR_BADXDR);
226 
227 	args->cbl_layout_type = ntohl(*p++);
228 	/* Depite the spec's xdr, iomode really belongs in the FILE switch,
229 	 * as it is unusable and ignored with the other types.
230 	 */
231 	iomode = ntohl(*p++);
232 	args->cbl_layoutchanged = ntohl(*p++);
233 	args->cbl_recall_type = ntohl(*p++);
234 
235 	if (args->cbl_recall_type == RETURN_FILE) {
236 		args->cbl_range.iomode = iomode;
237 		status = decode_fh(xdr, &args->cbl_fh);
238 		if (unlikely(status != 0))
239 			return status;
240 
241 		p = xdr_inline_decode(xdr, 2 * sizeof(uint64_t));
242 		if (unlikely(p == NULL))
243 			return htonl(NFS4ERR_BADXDR);
244 		p = xdr_decode_hyper(p, &args->cbl_range.offset);
245 		p = xdr_decode_hyper(p, &args->cbl_range.length);
246 		return decode_layout_stateid(xdr, &args->cbl_stateid);
247 	} else if (args->cbl_recall_type == RETURN_FSID) {
248 		p = xdr_inline_decode(xdr, 2 * sizeof(uint64_t));
249 		if (unlikely(p == NULL))
250 			return htonl(NFS4ERR_BADXDR);
251 		p = xdr_decode_hyper(p, &args->cbl_fsid.major);
252 		p = xdr_decode_hyper(p, &args->cbl_fsid.minor);
253 	} else if (args->cbl_recall_type != RETURN_ALL)
254 		return htonl(NFS4ERR_BADXDR);
255 	return 0;
256 }
257 
258 static
259 __be32 decode_devicenotify_args(struct svc_rqst *rqstp,
260 				struct xdr_stream *xdr,
261 				void *argp)
262 {
263 	struct cb_devicenotifyargs *args = argp;
264 	uint32_t tmp, n, i;
265 	__be32 *p;
266 	__be32 status = 0;
267 
268 	/* Num of device notifications */
269 	p = xdr_inline_decode(xdr, sizeof(uint32_t));
270 	if (unlikely(p == NULL)) {
271 		status = htonl(NFS4ERR_BADXDR);
272 		goto out;
273 	}
274 	n = ntohl(*p++);
275 	if (n == 0)
276 		goto out;
277 
278 	args->devs = kmalloc_array(n, sizeof(*args->devs), GFP_KERNEL);
279 	if (!args->devs) {
280 		status = htonl(NFS4ERR_DELAY);
281 		goto out;
282 	}
283 
284 	/* Decode each dev notification */
285 	for (i = 0; i < n; i++) {
286 		struct cb_devicenotifyitem *dev = &args->devs[i];
287 
288 		p = xdr_inline_decode(xdr, (4 * sizeof(uint32_t)) +
289 				      NFS4_DEVICEID4_SIZE);
290 		if (unlikely(p == NULL)) {
291 			status = htonl(NFS4ERR_BADXDR);
292 			goto err;
293 		}
294 
295 		tmp = ntohl(*p++);	/* bitmap size */
296 		if (tmp != 1) {
297 			status = htonl(NFS4ERR_INVAL);
298 			goto err;
299 		}
300 		dev->cbd_notify_type = ntohl(*p++);
301 		if (dev->cbd_notify_type != NOTIFY_DEVICEID4_CHANGE &&
302 		    dev->cbd_notify_type != NOTIFY_DEVICEID4_DELETE) {
303 			status = htonl(NFS4ERR_INVAL);
304 			goto err;
305 		}
306 
307 		tmp = ntohl(*p++);	/* opaque size */
308 		if (((dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE) &&
309 		     (tmp != NFS4_DEVICEID4_SIZE + 8)) ||
310 		    ((dev->cbd_notify_type == NOTIFY_DEVICEID4_DELETE) &&
311 		     (tmp != NFS4_DEVICEID4_SIZE + 4))) {
312 			status = htonl(NFS4ERR_INVAL);
313 			goto err;
314 		}
315 		dev->cbd_layout_type = ntohl(*p++);
316 		memcpy(dev->cbd_dev_id.data, p, NFS4_DEVICEID4_SIZE);
317 		p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
318 
319 		if (dev->cbd_layout_type == NOTIFY_DEVICEID4_CHANGE) {
320 			p = xdr_inline_decode(xdr, sizeof(uint32_t));
321 			if (unlikely(p == NULL)) {
322 				status = htonl(NFS4ERR_BADXDR);
323 				goto err;
324 			}
325 			dev->cbd_immediate = ntohl(*p++);
326 		} else {
327 			dev->cbd_immediate = 0;
328 		}
329 
330 		dprintk("%s: type %d layout 0x%x immediate %d\n",
331 			__func__, dev->cbd_notify_type, dev->cbd_layout_type,
332 			dev->cbd_immediate);
333 	}
334 	args->ndevs = n;
335 	dprintk("%s: ndevs %d\n", __func__, args->ndevs);
336 	return 0;
337 err:
338 	kfree(args->devs);
339 out:
340 	args->devs = NULL;
341 	args->ndevs = 0;
342 	dprintk("%s: status %d ndevs %d\n",
343 		__func__, ntohl(status), args->ndevs);
344 	return status;
345 }
346 
347 static __be32 decode_sessionid(struct xdr_stream *xdr,
348 				 struct nfs4_sessionid *sid)
349 {
350 	__be32 *p;
351 
352 	p = xdr_inline_decode(xdr, NFS4_MAX_SESSIONID_LEN);
353 	if (unlikely(p == NULL))
354 		return htonl(NFS4ERR_RESOURCE);
355 
356 	memcpy(sid->data, p, NFS4_MAX_SESSIONID_LEN);
357 	return 0;
358 }
359 
360 static __be32 decode_rc_list(struct xdr_stream *xdr,
361 			       struct referring_call_list *rc_list)
362 {
363 	__be32 *p;
364 	int i;
365 	__be32 status;
366 
367 	status = decode_sessionid(xdr, &rc_list->rcl_sessionid);
368 	if (status)
369 		goto out;
370 
371 	status = htonl(NFS4ERR_RESOURCE);
372 	p = xdr_inline_decode(xdr, sizeof(uint32_t));
373 	if (unlikely(p == NULL))
374 		goto out;
375 
376 	rc_list->rcl_nrefcalls = ntohl(*p++);
377 	if (rc_list->rcl_nrefcalls) {
378 		if (unlikely(rc_list->rcl_nrefcalls > xdr->buf->len))
379 			goto out;
380 		p = xdr_inline_decode(xdr,
381 			     rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
382 		if (unlikely(p == NULL))
383 			goto out;
384 		rc_list->rcl_refcalls = kmalloc_array(rc_list->rcl_nrefcalls,
385 						sizeof(*rc_list->rcl_refcalls),
386 						GFP_KERNEL);
387 		if (unlikely(rc_list->rcl_refcalls == NULL))
388 			goto out;
389 		for (i = 0; i < rc_list->rcl_nrefcalls; i++) {
390 			rc_list->rcl_refcalls[i].rc_sequenceid = ntohl(*p++);
391 			rc_list->rcl_refcalls[i].rc_slotid = ntohl(*p++);
392 		}
393 	}
394 	status = 0;
395 
396 out:
397 	return status;
398 }
399 
400 static __be32 decode_cb_sequence_args(struct svc_rqst *rqstp,
401 					struct xdr_stream *xdr,
402 					void *argp)
403 {
404 	struct cb_sequenceargs *args = argp;
405 	__be32 *p;
406 	int i;
407 	__be32 status;
408 
409 	status = decode_sessionid(xdr, &args->csa_sessionid);
410 	if (status)
411 		return status;
412 
413 	p = xdr_inline_decode(xdr, 5 * sizeof(uint32_t));
414 	if (unlikely(p == NULL))
415 		return htonl(NFS4ERR_RESOURCE);
416 
417 	args->csa_addr = svc_addr(rqstp);
418 	args->csa_sequenceid = ntohl(*p++);
419 	args->csa_slotid = ntohl(*p++);
420 	args->csa_highestslotid = ntohl(*p++);
421 	args->csa_cachethis = ntohl(*p++);
422 	args->csa_nrclists = ntohl(*p++);
423 	args->csa_rclists = NULL;
424 	if (args->csa_nrclists) {
425 		args->csa_rclists = kmalloc_array(args->csa_nrclists,
426 						  sizeof(*args->csa_rclists),
427 						  GFP_KERNEL);
428 		if (unlikely(args->csa_rclists == NULL))
429 			return htonl(NFS4ERR_RESOURCE);
430 
431 		for (i = 0; i < args->csa_nrclists; i++) {
432 			status = decode_rc_list(xdr, &args->csa_rclists[i]);
433 			if (status) {
434 				args->csa_nrclists = i;
435 				goto out_free;
436 			}
437 		}
438 	}
439 	return 0;
440 
441 out_free:
442 	for (i = 0; i < args->csa_nrclists; i++)
443 		kfree(args->csa_rclists[i].rcl_refcalls);
444 	kfree(args->csa_rclists);
445 	return status;
446 }
447 
448 static __be32 decode_recallany_args(struct svc_rqst *rqstp,
449 				      struct xdr_stream *xdr,
450 				      void *argp)
451 {
452 	struct cb_recallanyargs *args = argp;
453 	uint32_t bitmap[3];
454 	__be32 *p, status;
455 
456 	p = xdr_inline_decode(xdr, 4);
457 	if (unlikely(p == NULL))
458 		return htonl(NFS4ERR_BADXDR);
459 	args->craa_objs_to_keep = ntohl(*p++);
460 	status = decode_bitmap(xdr, bitmap);
461 	if (unlikely(status))
462 		return status;
463 	args->craa_type_mask = bitmap[0];
464 
465 	return 0;
466 }
467 
468 static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
469 					struct xdr_stream *xdr,
470 					void *argp)
471 {
472 	struct cb_recallslotargs *args = argp;
473 	__be32 *p;
474 
475 	p = xdr_inline_decode(xdr, 4);
476 	if (unlikely(p == NULL))
477 		return htonl(NFS4ERR_BADXDR);
478 	args->crsa_target_highest_slotid = ntohl(*p++);
479 	return 0;
480 }
481 
482 static __be32 decode_lockowner(struct xdr_stream *xdr, struct cb_notify_lock_args *args)
483 {
484 	__be32		*p;
485 	unsigned int	len;
486 
487 	p = xdr_inline_decode(xdr, 12);
488 	if (unlikely(p == NULL))
489 		return htonl(NFS4ERR_BADXDR);
490 
491 	p = xdr_decode_hyper(p, &args->cbnl_owner.clientid);
492 	len = be32_to_cpu(*p);
493 
494 	p = xdr_inline_decode(xdr, len);
495 	if (unlikely(p == NULL))
496 		return htonl(NFS4ERR_BADXDR);
497 
498 	/* Only try to decode if the length is right */
499 	if (len == 20) {
500 		p += 2;	/* skip "lock id:" */
501 		args->cbnl_owner.s_dev = be32_to_cpu(*p++);
502 		xdr_decode_hyper(p, &args->cbnl_owner.id);
503 		args->cbnl_valid = true;
504 	} else {
505 		args->cbnl_owner.s_dev = 0;
506 		args->cbnl_owner.id = 0;
507 		args->cbnl_valid = false;
508 	}
509 	return 0;
510 }
511 
512 static __be32 decode_notify_lock_args(struct svc_rqst *rqstp,
513 		struct xdr_stream *xdr, void *argp)
514 {
515 	struct cb_notify_lock_args *args = argp;
516 	__be32 status;
517 
518 	status = decode_fh(xdr, &args->cbnl_fh);
519 	if (unlikely(status != 0))
520 		return status;
521 	return decode_lockowner(xdr, args);
522 }
523 
524 #endif /* CONFIG_NFS_V4_1 */
525 #ifdef CONFIG_NFS_V4_2
526 static __be32 decode_write_response(struct xdr_stream *xdr,
527 					struct cb_offloadargs *args)
528 {
529 	__be32 *p;
530 
531 	/* skip the always zero field */
532 	p = xdr_inline_decode(xdr, 4);
533 	if (unlikely(!p))
534 		goto out;
535 	p++;
536 
537 	/* decode count, stable_how, verifier */
538 	p = xdr_inline_decode(xdr, 8 + 4);
539 	if (unlikely(!p))
540 		goto out;
541 	p = xdr_decode_hyper(p, &args->wr_count);
542 	args->wr_writeverf.committed = be32_to_cpup(p);
543 	p = xdr_inline_decode(xdr, NFS4_VERIFIER_SIZE);
544 	if (likely(p)) {
545 		memcpy(&args->wr_writeverf.verifier.data[0], p,
546 			NFS4_VERIFIER_SIZE);
547 		return 0;
548 	}
549 out:
550 	return htonl(NFS4ERR_RESOURCE);
551 }
552 
553 static __be32 decode_offload_args(struct svc_rqst *rqstp,
554 					struct xdr_stream *xdr,
555 					void *data)
556 {
557 	struct cb_offloadargs *args = data;
558 	__be32 *p;
559 	__be32 status;
560 
561 	/* decode fh */
562 	status = decode_fh(xdr, &args->coa_fh);
563 	if (unlikely(status != 0))
564 		return status;
565 
566 	/* decode stateid */
567 	status = decode_stateid(xdr, &args->coa_stateid);
568 	if (unlikely(status != 0))
569 		return status;
570 
571 	/* decode status */
572 	p = xdr_inline_decode(xdr, 4);
573 	if (unlikely(!p))
574 		goto out;
575 	args->error = ntohl(*p++);
576 	if (!args->error) {
577 		status = decode_write_response(xdr, args);
578 		if (unlikely(status != 0))
579 			return status;
580 	} else {
581 		p = xdr_inline_decode(xdr, 8);
582 		if (unlikely(!p))
583 			goto out;
584 		p = xdr_decode_hyper(p, &args->wr_count);
585 	}
586 	return 0;
587 out:
588 	return htonl(NFS4ERR_RESOURCE);
589 }
590 #endif /* CONFIG_NFS_V4_2 */
591 static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
592 {
593 	if (unlikely(xdr_stream_encode_opaque(xdr, str, len) < 0))
594 		return cpu_to_be32(NFS4ERR_RESOURCE);
595 	return 0;
596 }
597 
598 static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, size_t sz)
599 {
600 	if (xdr_stream_encode_uint32_array(xdr, bitmap, sz) < 0)
601 		return cpu_to_be32(NFS4ERR_RESOURCE);
602 	return 0;
603 }
604 
605 static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
606 {
607 	__be32 *p;
608 
609 	if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
610 		return 0;
611 	p = xdr_reserve_space(xdr, 8);
612 	if (unlikely(!p))
613 		return htonl(NFS4ERR_RESOURCE);
614 	p = xdr_encode_hyper(p, change);
615 	return 0;
616 }
617 
618 static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
619 {
620 	__be32 *p;
621 
622 	if (!(bitmap[0] & FATTR4_WORD0_SIZE))
623 		return 0;
624 	p = xdr_reserve_space(xdr, 8);
625 	if (unlikely(!p))
626 		return htonl(NFS4ERR_RESOURCE);
627 	p = xdr_encode_hyper(p, size);
628 	return 0;
629 }
630 
631 static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec64 *time)
632 {
633 	__be32 *p;
634 
635 	p = xdr_reserve_space(xdr, 12);
636 	if (unlikely(!p))
637 		return htonl(NFS4ERR_RESOURCE);
638 	p = xdr_encode_hyper(p, time->tv_sec);
639 	*p = htonl(time->tv_nsec);
640 	return 0;
641 }
642 
643 static __be32 encode_attr_atime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec64 *time)
644 {
645 	if (!(bitmap[1] & FATTR4_WORD1_TIME_ACCESS))
646 		return 0;
647 	return encode_attr_time(xdr,time);
648 }
649 
650 static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec64 *time)
651 {
652 	if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
653 		return 0;
654 	return encode_attr_time(xdr,time);
655 }
656 
657 static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec64 *time)
658 {
659 	if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
660 		return 0;
661 	return encode_attr_time(xdr,time);
662 }
663 
664 static __be32 encode_attr_delegatime(struct xdr_stream *xdr,
665 				     const uint32_t *bitmap,
666 				     const struct timespec64 *time)
667 {
668 	if (!(bitmap[2] & FATTR4_WORD2_TIME_DELEG_ACCESS))
669 		return 0;
670 	return encode_attr_time(xdr,time);
671 }
672 
673 static __be32 encode_attr_delegmtime(struct xdr_stream *xdr,
674 				     const uint32_t *bitmap,
675 				     const struct timespec64 *time)
676 {
677 	if (!(bitmap[2] & FATTR4_WORD2_TIME_DELEG_MODIFY))
678 		return 0;
679 	return encode_attr_time(xdr,time);
680 }
681 
682 static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
683 {
684 	__be32 status;
685 
686 	hdr->status = xdr_reserve_space(xdr, 4);
687 	if (unlikely(hdr->status == NULL))
688 		return htonl(NFS4ERR_RESOURCE);
689 	status = encode_string(xdr, hdr->taglen, hdr->tag);
690 	if (unlikely(status != 0))
691 		return status;
692 	hdr->nops = xdr_reserve_space(xdr, 4);
693 	if (unlikely(hdr->nops == NULL))
694 		return htonl(NFS4ERR_RESOURCE);
695 	return 0;
696 }
697 
698 static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
699 {
700 	__be32 *p;
701 
702 	p = xdr_reserve_space(xdr, 8);
703 	if (unlikely(p == NULL))
704 		return htonl(NFS4ERR_RESOURCE_HDR);
705 	*p++ = htonl(op);
706 	*p = res;
707 	return 0;
708 }
709 
710 static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr,
711 		const void *resp)
712 {
713 	const struct cb_getattrres *res = resp;
714 	__be32 *savep = NULL;
715 	__be32 status = res->status;
716 
717 	if (unlikely(status != 0))
718 		goto out;
719 	status = encode_attr_bitmap(xdr, res->bitmap, ARRAY_SIZE(res->bitmap));
720 	if (unlikely(status != 0))
721 		goto out;
722 	status = cpu_to_be32(NFS4ERR_RESOURCE);
723 	savep = xdr_reserve_space(xdr, sizeof(*savep));
724 	if (unlikely(!savep))
725 		goto out;
726 	status = encode_attr_change(xdr, res->bitmap, res->change_attr);
727 	if (unlikely(status != 0))
728 		goto out;
729 	status = encode_attr_size(xdr, res->bitmap, res->size);
730 	if (unlikely(status != 0))
731 		goto out;
732 	status = encode_attr_atime(xdr, res->bitmap, &res->atime);
733 	if (unlikely(status != 0))
734 		goto out;
735 	status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
736 	if (unlikely(status != 0))
737 		goto out;
738 	status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
739 	if (unlikely(status != 0))
740 		goto out;
741 	status = encode_attr_delegatime(xdr, res->bitmap, &res->atime);
742 	if (unlikely(status != 0))
743 		goto out;
744 	status = encode_attr_delegmtime(xdr, res->bitmap, &res->mtime);
745 	*savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
746 out:
747 	return status;
748 }
749 
750 #if defined(CONFIG_NFS_V4_1)
751 
752 static __be32 encode_sessionid(struct xdr_stream *xdr,
753 				 const struct nfs4_sessionid *sid)
754 {
755 	__be32 *p;
756 
757 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN);
758 	if (unlikely(p == NULL))
759 		return htonl(NFS4ERR_RESOURCE);
760 
761 	memcpy(p, sid, NFS4_MAX_SESSIONID_LEN);
762 	return 0;
763 }
764 
765 static __be32 encode_cb_sequence_res(struct svc_rqst *rqstp,
766 				       struct xdr_stream *xdr,
767 				       const void *resp)
768 {
769 	const struct cb_sequenceres *res = resp;
770 	__be32 *p;
771 	__be32 status = res->csr_status;
772 
773 	if (unlikely(status != 0))
774 		return status;
775 
776 	status = encode_sessionid(xdr, &res->csr_sessionid);
777 	if (status)
778 		return status;
779 
780 	p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
781 	if (unlikely(p == NULL))
782 		return htonl(NFS4ERR_RESOURCE);
783 
784 	*p++ = htonl(res->csr_sequenceid);
785 	*p++ = htonl(res->csr_slotid);
786 	*p++ = htonl(res->csr_highestslotid);
787 	*p++ = htonl(res->csr_target_highestslotid);
788 	return 0;
789 }
790 
791 static __be32
792 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
793 {
794 	if (op_nr == OP_CB_SEQUENCE) {
795 		if (nop != 0)
796 			return htonl(NFS4ERR_SEQUENCE_POS);
797 	} else {
798 		if (nop == 0)
799 			return htonl(NFS4ERR_OP_NOT_IN_SESSION);
800 	}
801 
802 	switch (op_nr) {
803 	case OP_CB_GETATTR:
804 	case OP_CB_RECALL:
805 	case OP_CB_SEQUENCE:
806 	case OP_CB_RECALL_ANY:
807 	case OP_CB_RECALL_SLOT:
808 	case OP_CB_LAYOUTRECALL:
809 	case OP_CB_NOTIFY_DEVICEID:
810 	case OP_CB_NOTIFY_LOCK:
811 		*op = &callback_ops[op_nr];
812 		break;
813 
814 	case OP_CB_NOTIFY:
815 	case OP_CB_PUSH_DELEG:
816 	case OP_CB_RECALLABLE_OBJ_AVAIL:
817 	case OP_CB_WANTS_CANCELLED:
818 		return htonl(NFS4ERR_NOTSUPP);
819 
820 	default:
821 		return htonl(NFS4ERR_OP_ILLEGAL);
822 	}
823 
824 	return htonl(NFS_OK);
825 }
826 
827 static void nfs4_callback_free_slot(struct nfs4_session *session,
828 		struct nfs4_slot *slot)
829 {
830 	struct nfs4_slot_table *tbl = &session->bc_slot_table;
831 
832 	spin_lock(&tbl->slot_tbl_lock);
833 	/*
834 	 * Let the state manager know callback processing done.
835 	 * A single slot, so highest used slotid is either 0 or -1
836 	 */
837 	nfs4_free_slot(tbl, slot);
838 	spin_unlock(&tbl->slot_tbl_lock);
839 }
840 
841 static void nfs4_cb_free_slot(struct cb_process_state *cps)
842 {
843 	if (cps->slot) {
844 		nfs4_callback_free_slot(cps->clp->cl_session, cps->slot);
845 		cps->slot = NULL;
846 	}
847 }
848 
849 #else /* CONFIG_NFS_V4_1 */
850 
851 static __be32
852 preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
853 {
854 	return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
855 }
856 
857 static void nfs4_cb_free_slot(struct cb_process_state *cps)
858 {
859 }
860 #endif /* CONFIG_NFS_V4_1 */
861 
862 #ifdef CONFIG_NFS_V4_2
863 static __be32
864 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
865 {
866 	__be32 status = preprocess_nfs41_op(nop, op_nr, op);
867 	if (status != htonl(NFS4ERR_OP_ILLEGAL))
868 		return status;
869 
870 	if (op_nr == OP_CB_OFFLOAD) {
871 		*op = &callback_ops[op_nr];
872 		return htonl(NFS_OK);
873 	} else
874 		return htonl(NFS4ERR_NOTSUPP);
875 	return htonl(NFS4ERR_OP_ILLEGAL);
876 }
877 #else /* CONFIG_NFS_V4_2 */
878 static __be32
879 preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
880 {
881 	return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
882 }
883 #endif /* CONFIG_NFS_V4_2 */
884 
885 static __be32
886 preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
887 {
888 	switch (op_nr) {
889 	case OP_CB_GETATTR:
890 	case OP_CB_RECALL:
891 		*op = &callback_ops[op_nr];
892 		break;
893 	default:
894 		return htonl(NFS4ERR_OP_ILLEGAL);
895 	}
896 
897 	return htonl(NFS_OK);
898 }
899 
900 static __be32 process_op(int nop, struct svc_rqst *rqstp,
901 			 struct cb_process_state *cps)
902 {
903 	struct xdr_stream *xdr_out = &rqstp->rq_res_stream;
904 	struct callback_op *op = &callback_ops[0];
905 	unsigned int op_nr;
906 	__be32 status;
907 	long maxlen;
908 	__be32 res;
909 
910 	status = decode_op_hdr(&rqstp->rq_arg_stream, &op_nr);
911 	if (unlikely(status))
912 		return status;
913 
914 	switch (cps->minorversion) {
915 	case 0:
916 		status = preprocess_nfs4_op(op_nr, &op);
917 		break;
918 	case 1:
919 		status = preprocess_nfs41_op(nop, op_nr, &op);
920 		break;
921 	case 2:
922 		status = preprocess_nfs42_op(nop, op_nr, &op);
923 		break;
924 	default:
925 		status = htonl(NFS4ERR_MINOR_VERS_MISMATCH);
926 	}
927 
928 	if (status == htonl(NFS4ERR_OP_ILLEGAL))
929 		op_nr = OP_CB_ILLEGAL;
930 	if (status)
931 		goto encode_hdr;
932 
933 	if (cps->drc_status) {
934 		status = cps->drc_status;
935 		goto encode_hdr;
936 	}
937 
938 	maxlen = xdr_out->end - xdr_out->p;
939 	if (maxlen > 0 && maxlen < PAGE_SIZE) {
940 		status = op->decode_args(rqstp, &rqstp->rq_arg_stream,
941 					 rqstp->rq_argp);
942 		if (likely(status == 0))
943 			status = op->process_op(rqstp->rq_argp, rqstp->rq_resp,
944 						cps);
945 	} else
946 		status = htonl(NFS4ERR_RESOURCE);
947 
948 encode_hdr:
949 	res = encode_op_hdr(xdr_out, op_nr, status);
950 	if (unlikely(res))
951 		return res;
952 	if (op->encode_res != NULL && status == 0)
953 		status = op->encode_res(rqstp, xdr_out, rqstp->rq_resp);
954 	return status;
955 }
956 
957 /*
958  * Decode, process and encode a COMPOUND
959  */
960 static __be32 nfs4_callback_compound(struct svc_rqst *rqstp)
961 {
962 	struct cb_compound_hdr_arg hdr_arg = { 0 };
963 	struct cb_compound_hdr_res hdr_res = { NULL };
964 	struct cb_process_state cps = {
965 		.drc_status = 0,
966 		.clp = NULL,
967 		.net = SVC_NET(rqstp),
968 	};
969 	unsigned int nops = 0;
970 	__be32 status;
971 
972 	status = decode_compound_hdr_arg(&rqstp->rq_arg_stream, &hdr_arg);
973 	if (status == htonl(NFS4ERR_RESOURCE))
974 		return rpc_garbage_args;
975 
976 	if (hdr_arg.minorversion == 0) {
977 		cps.clp = nfs4_find_client_ident(SVC_NET(rqstp), hdr_arg.cb_ident);
978 		if (!cps.clp) {
979 			trace_nfs_cb_no_clp(rqstp->rq_xid, hdr_arg.cb_ident);
980 			goto out_invalidcred;
981 		}
982 		if (!check_gss_callback_principal(cps.clp, rqstp)) {
983 			trace_nfs_cb_badprinc(rqstp->rq_xid, hdr_arg.cb_ident);
984 			nfs_put_client(cps.clp);
985 			goto out_invalidcred;
986 		}
987 	}
988 
989 	cps.minorversion = hdr_arg.minorversion;
990 	hdr_res.taglen = hdr_arg.taglen;
991 	hdr_res.tag = hdr_arg.tag;
992 	if (encode_compound_hdr_res(&rqstp->rq_res_stream, &hdr_res) != 0) {
993 		if (cps.clp)
994 			nfs_put_client(cps.clp);
995 		return rpc_system_err;
996 	}
997 	while (status == 0 && nops != hdr_arg.nops) {
998 		status = process_op(nops, rqstp, &cps);
999 		nops++;
1000 	}
1001 
1002 	/* Buffer overflow in decode_ops_hdr or encode_ops_hdr. Return
1003 	* resource error in cb_compound status without returning op */
1004 	if (unlikely(status == htonl(NFS4ERR_RESOURCE_HDR))) {
1005 		status = htonl(NFS4ERR_RESOURCE);
1006 		nops--;
1007 	}
1008 
1009 	if (svc_is_backchannel(rqstp) && cps.clp) {
1010 		rqstp->bc_to_initval = cps.clp->cl_rpcclient->cl_timeout->to_initval;
1011 		rqstp->bc_to_retries = cps.clp->cl_rpcclient->cl_timeout->to_retries;
1012 	}
1013 
1014 	*hdr_res.status = status;
1015 	*hdr_res.nops = htonl(nops);
1016 	nfs4_cb_free_slot(&cps);
1017 	nfs_put_client(cps.clp);
1018 	return rpc_success;
1019 
1020 out_invalidcred:
1021 	pr_warn_ratelimited("NFS: NFSv4 callback contains invalid cred\n");
1022 	rqstp->rq_auth_stat = rpc_autherr_badcred;
1023 	return rpc_success;
1024 }
1025 
1026 static int
1027 nfs_callback_dispatch(struct svc_rqst *rqstp)
1028 {
1029 	const struct svc_procedure *procp = rqstp->rq_procinfo;
1030 
1031 	*rqstp->rq_accept_statp = procp->pc_func(rqstp);
1032 	return 1;
1033 }
1034 
1035 /*
1036  * Define NFS4 callback COMPOUND ops.
1037  */
1038 static struct callback_op callback_ops[] = {
1039 	[0] = {
1040 		.res_maxsize = CB_OP_HDR_RES_MAXSZ,
1041 	},
1042 	[OP_CB_GETATTR] = {
1043 		.process_op = nfs4_callback_getattr,
1044 		.decode_args = decode_getattr_args,
1045 		.encode_res = encode_getattr_res,
1046 		.res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
1047 	},
1048 	[OP_CB_RECALL] = {
1049 		.process_op = nfs4_callback_recall,
1050 		.decode_args = decode_recall_args,
1051 		.res_maxsize = CB_OP_RECALL_RES_MAXSZ,
1052 	},
1053 #if defined(CONFIG_NFS_V4_1)
1054 	[OP_CB_LAYOUTRECALL] = {
1055 		.process_op = nfs4_callback_layoutrecall,
1056 		.decode_args = decode_layoutrecall_args,
1057 		.res_maxsize = CB_OP_LAYOUTRECALL_RES_MAXSZ,
1058 	},
1059 	[OP_CB_NOTIFY_DEVICEID] = {
1060 		.process_op = nfs4_callback_devicenotify,
1061 		.decode_args = decode_devicenotify_args,
1062 		.res_maxsize = CB_OP_DEVICENOTIFY_RES_MAXSZ,
1063 	},
1064 	[OP_CB_SEQUENCE] = {
1065 		.process_op = nfs4_callback_sequence,
1066 		.decode_args = decode_cb_sequence_args,
1067 		.encode_res = encode_cb_sequence_res,
1068 		.res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
1069 	},
1070 	[OP_CB_RECALL_ANY] = {
1071 		.process_op = nfs4_callback_recallany,
1072 		.decode_args = decode_recallany_args,
1073 		.res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
1074 	},
1075 	[OP_CB_RECALL_SLOT] = {
1076 		.process_op = nfs4_callback_recallslot,
1077 		.decode_args = decode_recallslot_args,
1078 		.res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
1079 	},
1080 	[OP_CB_NOTIFY_LOCK] = {
1081 		.process_op = nfs4_callback_notify_lock,
1082 		.decode_args = decode_notify_lock_args,
1083 		.res_maxsize = CB_OP_NOTIFY_LOCK_RES_MAXSZ,
1084 	},
1085 #endif /* CONFIG_NFS_V4_1 */
1086 #ifdef CONFIG_NFS_V4_2
1087 	[OP_CB_OFFLOAD] = {
1088 		.process_op = nfs4_callback_offload,
1089 		.decode_args = decode_offload_args,
1090 		.res_maxsize = CB_OP_OFFLOAD_RES_MAXSZ,
1091 	},
1092 #endif /* CONFIG_NFS_V4_2 */
1093 };
1094 
1095 /*
1096  * Define NFS4 callback procedures
1097  */
1098 static const struct svc_procedure nfs4_callback_procedures1[] = {
1099 	[CB_NULL] = {
1100 		.pc_func = nfs4_callback_null,
1101 		.pc_encode = nfs4_encode_void,
1102 		.pc_xdrressize = 1,
1103 		.pc_name = "NULL",
1104 	},
1105 	[CB_COMPOUND] = {
1106 		.pc_func = nfs4_callback_compound,
1107 		.pc_encode = nfs4_encode_void,
1108 		.pc_argsize = 256,
1109 		.pc_argzero = 256,
1110 		.pc_ressize = 256,
1111 		.pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
1112 		.pc_name = "COMPOUND",
1113 	}
1114 };
1115 
1116 static DEFINE_PER_CPU_ALIGNED(unsigned long,
1117 			      nfs4_callback_count1[ARRAY_SIZE(nfs4_callback_procedures1)]);
1118 const struct svc_version nfs4_callback_version1 = {
1119 	.vs_vers = 1,
1120 	.vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1121 	.vs_proc = nfs4_callback_procedures1,
1122 	.vs_count = nfs4_callback_count1,
1123 	.vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1124 	.vs_dispatch = nfs_callback_dispatch,
1125 	.vs_hidden = true,
1126 	.vs_need_cong_ctrl = true,
1127 };
1128 
1129 static DEFINE_PER_CPU_ALIGNED(unsigned long,
1130 			      nfs4_callback_count4[ARRAY_SIZE(nfs4_callback_procedures1)]);
1131 const struct svc_version nfs4_callback_version4 = {
1132 	.vs_vers = 4,
1133 	.vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1134 	.vs_proc = nfs4_callback_procedures1,
1135 	.vs_count = nfs4_callback_count4,
1136 	.vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1137 	.vs_dispatch = nfs_callback_dispatch,
1138 	.vs_hidden = true,
1139 	.vs_need_cong_ctrl = true,
1140 };
1141