xref: /kernel/linux/linux-5.10/fs/nfs/callback_xdr.c (revision 8c2ecf20)
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, ctime, mtime */\
29					 (2 + 2 + 3 + 3) * 4)
30#define CB_OP_RECALL_RES_MAXSZ		(CB_OP_HDR_RES_MAXSZ)
31
32#if defined(CONFIG_NFS_V4_1)
33#define CB_OP_LAYOUTRECALL_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
34#define CB_OP_DEVICENOTIFY_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
35#define CB_OP_SEQUENCE_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ + \
36					 NFS4_MAX_SESSIONID_LEN + \
37					 (1 + 3) * 4) // seqid, 3 slotids
38#define CB_OP_RECALLANY_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
39#define CB_OP_RECALLSLOT_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
40#define CB_OP_NOTIFY_LOCK_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
41#endif /* CONFIG_NFS_V4_1 */
42#ifdef CONFIG_NFS_V4_2
43#define CB_OP_OFFLOAD_RES_MAXSZ		(CB_OP_HDR_RES_MAXSZ)
44#endif /* CONFIG_NFS_V4_2 */
45
46#define NFSDBG_FACILITY NFSDBG_CALLBACK
47
48/* Internal error code */
49#define NFS4ERR_RESOURCE_HDR	11050
50
51struct callback_op {
52	__be32 (*process_op)(void *, void *, struct cb_process_state *);
53	__be32 (*decode_args)(struct svc_rqst *, struct xdr_stream *, void *);
54	__be32 (*encode_res)(struct svc_rqst *, struct xdr_stream *,
55			const void *);
56	long res_maxsize;
57};
58
59static struct callback_op callback_ops[];
60
61static __be32 nfs4_callback_null(struct svc_rqst *rqstp)
62{
63	return htonl(NFS4_OK);
64}
65
66static int nfs4_decode_void(struct svc_rqst *rqstp, __be32 *p)
67{
68	return xdr_argsize_check(rqstp, p);
69}
70
71static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p)
72{
73	return xdr_ressize_check(rqstp, p);
74}
75
76static __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
88static __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
106static __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	return 0;
123}
124
125static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
126{
127	__be32 *p;
128
129	p = xdr_inline_decode(xdr, NFS4_STATEID_SIZE);
130	if (unlikely(p == NULL))
131		return htonl(NFS4ERR_RESOURCE);
132	memcpy(stateid->data, p, NFS4_STATEID_SIZE);
133	return 0;
134}
135
136static __be32 decode_delegation_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
137{
138	stateid->type = NFS4_DELEGATION_STATEID_TYPE;
139	return decode_stateid(xdr, stateid);
140}
141
142static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
143{
144	__be32 *p;
145	__be32 status;
146
147	status = decode_string(xdr, &hdr->taglen, &hdr->tag, CB_OP_TAGLEN_MAXSZ);
148	if (unlikely(status != 0))
149		return status;
150	p = xdr_inline_decode(xdr, 12);
151	if (unlikely(p == NULL))
152		return htonl(NFS4ERR_RESOURCE);
153	hdr->minorversion = ntohl(*p++);
154	/* Check for minor version support */
155	if (hdr->minorversion <= NFS4_MAX_MINOR_VERSION) {
156		hdr->cb_ident = ntohl(*p++); /* ignored by v4.1 and v4.2 */
157	} else {
158		pr_warn_ratelimited("NFS: %s: NFSv4 server callback with "
159			"illegal minor version %u!\n",
160			__func__, hdr->minorversion);
161		return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
162	}
163	hdr->nops = ntohl(*p);
164	return 0;
165}
166
167static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
168{
169	__be32 *p;
170	p = xdr_inline_decode(xdr, 4);
171	if (unlikely(p == NULL))
172		return htonl(NFS4ERR_RESOURCE_HDR);
173	*op = ntohl(*p);
174	return 0;
175}
176
177static __be32 decode_getattr_args(struct svc_rqst *rqstp,
178		struct xdr_stream *xdr, void *argp)
179{
180	struct cb_getattrargs *args = argp;
181	__be32 status;
182
183	status = decode_fh(xdr, &args->fh);
184	if (unlikely(status != 0))
185		return status;
186	return decode_bitmap(xdr, args->bitmap);
187}
188
189static __be32 decode_recall_args(struct svc_rqst *rqstp,
190		struct xdr_stream *xdr, void *argp)
191{
192	struct cb_recallargs *args = argp;
193	__be32 *p;
194	__be32 status;
195
196	status = decode_delegation_stateid(xdr, &args->stateid);
197	if (unlikely(status != 0))
198		return status;
199	p = xdr_inline_decode(xdr, 4);
200	if (unlikely(p == NULL))
201		return htonl(NFS4ERR_RESOURCE);
202	args->truncate = ntohl(*p);
203	return decode_fh(xdr, &args->fh);
204}
205
206#if defined(CONFIG_NFS_V4_1)
207static __be32 decode_layout_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
208{
209	stateid->type = NFS4_LAYOUT_STATEID_TYPE;
210	return decode_stateid(xdr, stateid);
211}
212
213static __be32 decode_layoutrecall_args(struct svc_rqst *rqstp,
214				       struct xdr_stream *xdr, void *argp)
215{
216	struct cb_layoutrecallargs *args = argp;
217	__be32 *p;
218	__be32 status = 0;
219	uint32_t iomode;
220
221	p = xdr_inline_decode(xdr, 4 * sizeof(uint32_t));
222	if (unlikely(p == NULL))
223		return htonl(NFS4ERR_BADXDR);
224
225	args->cbl_layout_type = ntohl(*p++);
226	/* Depite the spec's xdr, iomode really belongs in the FILE switch,
227	 * as it is unusable and ignored with the other types.
228	 */
229	iomode = ntohl(*p++);
230	args->cbl_layoutchanged = ntohl(*p++);
231	args->cbl_recall_type = ntohl(*p++);
232
233	if (args->cbl_recall_type == RETURN_FILE) {
234		args->cbl_range.iomode = iomode;
235		status = decode_fh(xdr, &args->cbl_fh);
236		if (unlikely(status != 0))
237			return status;
238
239		p = xdr_inline_decode(xdr, 2 * sizeof(uint64_t));
240		if (unlikely(p == NULL))
241			return htonl(NFS4ERR_BADXDR);
242		p = xdr_decode_hyper(p, &args->cbl_range.offset);
243		p = xdr_decode_hyper(p, &args->cbl_range.length);
244		return decode_layout_stateid(xdr, &args->cbl_stateid);
245	} else if (args->cbl_recall_type == RETURN_FSID) {
246		p = xdr_inline_decode(xdr, 2 * sizeof(uint64_t));
247		if (unlikely(p == NULL))
248			return htonl(NFS4ERR_BADXDR);
249		p = xdr_decode_hyper(p, &args->cbl_fsid.major);
250		p = xdr_decode_hyper(p, &args->cbl_fsid.minor);
251	} else if (args->cbl_recall_type != RETURN_ALL)
252		return htonl(NFS4ERR_BADXDR);
253	return 0;
254}
255
256static
257__be32 decode_devicenotify_args(struct svc_rqst *rqstp,
258				struct xdr_stream *xdr,
259				void *argp)
260{
261	struct cb_devicenotifyargs *args = argp;
262	uint32_t tmp, n, i;
263	__be32 *p;
264	__be32 status = 0;
265
266	/* Num of device notifications */
267	p = xdr_inline_decode(xdr, sizeof(uint32_t));
268	if (unlikely(p == NULL)) {
269		status = htonl(NFS4ERR_BADXDR);
270		goto out;
271	}
272	n = ntohl(*p++);
273	if (n == 0)
274		goto out;
275
276	args->devs = kmalloc_array(n, sizeof(*args->devs), GFP_KERNEL);
277	if (!args->devs) {
278		status = htonl(NFS4ERR_DELAY);
279		goto out;
280	}
281
282	/* Decode each dev notification */
283	for (i = 0; i < n; i++) {
284		struct cb_devicenotifyitem *dev = &args->devs[i];
285
286		p = xdr_inline_decode(xdr, (4 * sizeof(uint32_t)) +
287				      NFS4_DEVICEID4_SIZE);
288		if (unlikely(p == NULL)) {
289			status = htonl(NFS4ERR_BADXDR);
290			goto err;
291		}
292
293		tmp = ntohl(*p++);	/* bitmap size */
294		if (tmp != 1) {
295			status = htonl(NFS4ERR_INVAL);
296			goto err;
297		}
298		dev->cbd_notify_type = ntohl(*p++);
299		if (dev->cbd_notify_type != NOTIFY_DEVICEID4_CHANGE &&
300		    dev->cbd_notify_type != NOTIFY_DEVICEID4_DELETE) {
301			status = htonl(NFS4ERR_INVAL);
302			goto err;
303		}
304
305		tmp = ntohl(*p++);	/* opaque size */
306		if (((dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE) &&
307		     (tmp != NFS4_DEVICEID4_SIZE + 8)) ||
308		    ((dev->cbd_notify_type == NOTIFY_DEVICEID4_DELETE) &&
309		     (tmp != NFS4_DEVICEID4_SIZE + 4))) {
310			status = htonl(NFS4ERR_INVAL);
311			goto err;
312		}
313		dev->cbd_layout_type = ntohl(*p++);
314		memcpy(dev->cbd_dev_id.data, p, NFS4_DEVICEID4_SIZE);
315		p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
316
317		if (dev->cbd_layout_type == NOTIFY_DEVICEID4_CHANGE) {
318			p = xdr_inline_decode(xdr, sizeof(uint32_t));
319			if (unlikely(p == NULL)) {
320				status = htonl(NFS4ERR_BADXDR);
321				goto err;
322			}
323			dev->cbd_immediate = ntohl(*p++);
324		} else {
325			dev->cbd_immediate = 0;
326		}
327
328		dprintk("%s: type %d layout 0x%x immediate %d\n",
329			__func__, dev->cbd_notify_type, dev->cbd_layout_type,
330			dev->cbd_immediate);
331	}
332	args->ndevs = n;
333	dprintk("%s: ndevs %d\n", __func__, args->ndevs);
334	return 0;
335err:
336	kfree(args->devs);
337out:
338	args->devs = NULL;
339	args->ndevs = 0;
340	dprintk("%s: status %d ndevs %d\n",
341		__func__, ntohl(status), args->ndevs);
342	return status;
343}
344
345static __be32 decode_sessionid(struct xdr_stream *xdr,
346				 struct nfs4_sessionid *sid)
347{
348	__be32 *p;
349
350	p = xdr_inline_decode(xdr, NFS4_MAX_SESSIONID_LEN);
351	if (unlikely(p == NULL))
352		return htonl(NFS4ERR_RESOURCE);
353
354	memcpy(sid->data, p, NFS4_MAX_SESSIONID_LEN);
355	return 0;
356}
357
358static __be32 decode_rc_list(struct xdr_stream *xdr,
359			       struct referring_call_list *rc_list)
360{
361	__be32 *p;
362	int i;
363	__be32 status;
364
365	status = decode_sessionid(xdr, &rc_list->rcl_sessionid);
366	if (status)
367		goto out;
368
369	status = htonl(NFS4ERR_RESOURCE);
370	p = xdr_inline_decode(xdr, sizeof(uint32_t));
371	if (unlikely(p == NULL))
372		goto out;
373
374	rc_list->rcl_nrefcalls = ntohl(*p++);
375	if (rc_list->rcl_nrefcalls) {
376		p = xdr_inline_decode(xdr,
377			     rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
378		if (unlikely(p == NULL))
379			goto out;
380		rc_list->rcl_refcalls = kmalloc_array(rc_list->rcl_nrefcalls,
381						sizeof(*rc_list->rcl_refcalls),
382						GFP_KERNEL);
383		if (unlikely(rc_list->rcl_refcalls == NULL))
384			goto out;
385		for (i = 0; i < rc_list->rcl_nrefcalls; i++) {
386			rc_list->rcl_refcalls[i].rc_sequenceid = ntohl(*p++);
387			rc_list->rcl_refcalls[i].rc_slotid = ntohl(*p++);
388		}
389	}
390	status = 0;
391
392out:
393	return status;
394}
395
396static __be32 decode_cb_sequence_args(struct svc_rqst *rqstp,
397					struct xdr_stream *xdr,
398					void *argp)
399{
400	struct cb_sequenceargs *args = argp;
401	__be32 *p;
402	int i;
403	__be32 status;
404
405	status = decode_sessionid(xdr, &args->csa_sessionid);
406	if (status)
407		return status;
408
409	p = xdr_inline_decode(xdr, 5 * sizeof(uint32_t));
410	if (unlikely(p == NULL))
411		return htonl(NFS4ERR_RESOURCE);
412
413	args->csa_addr = svc_addr(rqstp);
414	args->csa_sequenceid = ntohl(*p++);
415	args->csa_slotid = ntohl(*p++);
416	args->csa_highestslotid = ntohl(*p++);
417	args->csa_cachethis = ntohl(*p++);
418	args->csa_nrclists = ntohl(*p++);
419	args->csa_rclists = NULL;
420	if (args->csa_nrclists) {
421		args->csa_rclists = kmalloc_array(args->csa_nrclists,
422						  sizeof(*args->csa_rclists),
423						  GFP_KERNEL);
424		if (unlikely(args->csa_rclists == NULL))
425			return htonl(NFS4ERR_RESOURCE);
426
427		for (i = 0; i < args->csa_nrclists; i++) {
428			status = decode_rc_list(xdr, &args->csa_rclists[i]);
429			if (status) {
430				args->csa_nrclists = i;
431				goto out_free;
432			}
433		}
434	}
435	return 0;
436
437out_free:
438	for (i = 0; i < args->csa_nrclists; i++)
439		kfree(args->csa_rclists[i].rcl_refcalls);
440	kfree(args->csa_rclists);
441	return status;
442}
443
444static __be32 decode_recallany_args(struct svc_rqst *rqstp,
445				      struct xdr_stream *xdr,
446				      void *argp)
447{
448	struct cb_recallanyargs *args = argp;
449	uint32_t bitmap[2];
450	__be32 *p, status;
451
452	p = xdr_inline_decode(xdr, 4);
453	if (unlikely(p == NULL))
454		return htonl(NFS4ERR_BADXDR);
455	args->craa_objs_to_keep = ntohl(*p++);
456	status = decode_bitmap(xdr, bitmap);
457	if (unlikely(status))
458		return status;
459	args->craa_type_mask = bitmap[0];
460
461	return 0;
462}
463
464static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
465					struct xdr_stream *xdr,
466					void *argp)
467{
468	struct cb_recallslotargs *args = argp;
469	__be32 *p;
470
471	p = xdr_inline_decode(xdr, 4);
472	if (unlikely(p == NULL))
473		return htonl(NFS4ERR_BADXDR);
474	args->crsa_target_highest_slotid = ntohl(*p++);
475	return 0;
476}
477
478static __be32 decode_lockowner(struct xdr_stream *xdr, struct cb_notify_lock_args *args)
479{
480	__be32		*p;
481	unsigned int	len;
482
483	p = xdr_inline_decode(xdr, 12);
484	if (unlikely(p == NULL))
485		return htonl(NFS4ERR_BADXDR);
486
487	p = xdr_decode_hyper(p, &args->cbnl_owner.clientid);
488	len = be32_to_cpu(*p);
489
490	p = xdr_inline_decode(xdr, len);
491	if (unlikely(p == NULL))
492		return htonl(NFS4ERR_BADXDR);
493
494	/* Only try to decode if the length is right */
495	if (len == 20) {
496		p += 2;	/* skip "lock id:" */
497		args->cbnl_owner.s_dev = be32_to_cpu(*p++);
498		xdr_decode_hyper(p, &args->cbnl_owner.id);
499		args->cbnl_valid = true;
500	} else {
501		args->cbnl_owner.s_dev = 0;
502		args->cbnl_owner.id = 0;
503		args->cbnl_valid = false;
504	}
505	return 0;
506}
507
508static __be32 decode_notify_lock_args(struct svc_rqst *rqstp,
509		struct xdr_stream *xdr, void *argp)
510{
511	struct cb_notify_lock_args *args = argp;
512	__be32 status;
513
514	status = decode_fh(xdr, &args->cbnl_fh);
515	if (unlikely(status != 0))
516		return status;
517	return decode_lockowner(xdr, args);
518}
519
520#endif /* CONFIG_NFS_V4_1 */
521#ifdef CONFIG_NFS_V4_2
522static __be32 decode_write_response(struct xdr_stream *xdr,
523					struct cb_offloadargs *args)
524{
525	__be32 *p;
526
527	/* skip the always zero field */
528	p = xdr_inline_decode(xdr, 4);
529	if (unlikely(!p))
530		goto out;
531	p++;
532
533	/* decode count, stable_how, verifier */
534	p = xdr_inline_decode(xdr, 8 + 4);
535	if (unlikely(!p))
536		goto out;
537	p = xdr_decode_hyper(p, &args->wr_count);
538	args->wr_writeverf.committed = be32_to_cpup(p);
539	p = xdr_inline_decode(xdr, NFS4_VERIFIER_SIZE);
540	if (likely(p)) {
541		memcpy(&args->wr_writeverf.verifier.data[0], p,
542			NFS4_VERIFIER_SIZE);
543		return 0;
544	}
545out:
546	return htonl(NFS4ERR_RESOURCE);
547}
548
549static __be32 decode_offload_args(struct svc_rqst *rqstp,
550					struct xdr_stream *xdr,
551					void *data)
552{
553	struct cb_offloadargs *args = data;
554	__be32 *p;
555	__be32 status;
556
557	/* decode fh */
558	status = decode_fh(xdr, &args->coa_fh);
559	if (unlikely(status != 0))
560		return status;
561
562	/* decode stateid */
563	status = decode_stateid(xdr, &args->coa_stateid);
564	if (unlikely(status != 0))
565		return status;
566
567	/* decode status */
568	p = xdr_inline_decode(xdr, 4);
569	if (unlikely(!p))
570		goto out;
571	args->error = ntohl(*p++);
572	if (!args->error) {
573		status = decode_write_response(xdr, args);
574		if (unlikely(status != 0))
575			return status;
576	} else {
577		p = xdr_inline_decode(xdr, 8);
578		if (unlikely(!p))
579			goto out;
580		p = xdr_decode_hyper(p, &args->wr_count);
581	}
582	return 0;
583out:
584	return htonl(NFS4ERR_RESOURCE);
585}
586#endif /* CONFIG_NFS_V4_2 */
587static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
588{
589	if (unlikely(xdr_stream_encode_opaque(xdr, str, len) < 0))
590		return cpu_to_be32(NFS4ERR_RESOURCE);
591	return 0;
592}
593
594static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, size_t sz)
595{
596	if (xdr_stream_encode_uint32_array(xdr, bitmap, sz) < 0)
597		return cpu_to_be32(NFS4ERR_RESOURCE);
598	return 0;
599}
600
601static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
602{
603	__be32 *p;
604
605	if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
606		return 0;
607	p = xdr_reserve_space(xdr, 8);
608	if (unlikely(!p))
609		return htonl(NFS4ERR_RESOURCE);
610	p = xdr_encode_hyper(p, change);
611	return 0;
612}
613
614static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
615{
616	__be32 *p;
617
618	if (!(bitmap[0] & FATTR4_WORD0_SIZE))
619		return 0;
620	p = xdr_reserve_space(xdr, 8);
621	if (unlikely(!p))
622		return htonl(NFS4ERR_RESOURCE);
623	p = xdr_encode_hyper(p, size);
624	return 0;
625}
626
627static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec64 *time)
628{
629	__be32 *p;
630
631	p = xdr_reserve_space(xdr, 12);
632	if (unlikely(!p))
633		return htonl(NFS4ERR_RESOURCE);
634	p = xdr_encode_hyper(p, time->tv_sec);
635	*p = htonl(time->tv_nsec);
636	return 0;
637}
638
639static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec64 *time)
640{
641	if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
642		return 0;
643	return encode_attr_time(xdr,time);
644}
645
646static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec64 *time)
647{
648	if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
649		return 0;
650	return encode_attr_time(xdr,time);
651}
652
653static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
654{
655	__be32 status;
656
657	hdr->status = xdr_reserve_space(xdr, 4);
658	if (unlikely(hdr->status == NULL))
659		return htonl(NFS4ERR_RESOURCE);
660	status = encode_string(xdr, hdr->taglen, hdr->tag);
661	if (unlikely(status != 0))
662		return status;
663	hdr->nops = xdr_reserve_space(xdr, 4);
664	if (unlikely(hdr->nops == NULL))
665		return htonl(NFS4ERR_RESOURCE);
666	return 0;
667}
668
669static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
670{
671	__be32 *p;
672
673	p = xdr_reserve_space(xdr, 8);
674	if (unlikely(p == NULL))
675		return htonl(NFS4ERR_RESOURCE_HDR);
676	*p++ = htonl(op);
677	*p = res;
678	return 0;
679}
680
681static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr,
682		const void *resp)
683{
684	const struct cb_getattrres *res = resp;
685	__be32 *savep = NULL;
686	__be32 status = res->status;
687
688	if (unlikely(status != 0))
689		goto out;
690	status = encode_attr_bitmap(xdr, res->bitmap, ARRAY_SIZE(res->bitmap));
691	if (unlikely(status != 0))
692		goto out;
693	status = cpu_to_be32(NFS4ERR_RESOURCE);
694	savep = xdr_reserve_space(xdr, sizeof(*savep));
695	if (unlikely(!savep))
696		goto out;
697	status = encode_attr_change(xdr, res->bitmap, res->change_attr);
698	if (unlikely(status != 0))
699		goto out;
700	status = encode_attr_size(xdr, res->bitmap, res->size);
701	if (unlikely(status != 0))
702		goto out;
703	status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
704	if (unlikely(status != 0))
705		goto out;
706	status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
707	*savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
708out:
709	return status;
710}
711
712#if defined(CONFIG_NFS_V4_1)
713
714static __be32 encode_sessionid(struct xdr_stream *xdr,
715				 const struct nfs4_sessionid *sid)
716{
717	__be32 *p;
718
719	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN);
720	if (unlikely(p == NULL))
721		return htonl(NFS4ERR_RESOURCE);
722
723	memcpy(p, sid, NFS4_MAX_SESSIONID_LEN);
724	return 0;
725}
726
727static __be32 encode_cb_sequence_res(struct svc_rqst *rqstp,
728				       struct xdr_stream *xdr,
729				       const void *resp)
730{
731	const struct cb_sequenceres *res = resp;
732	__be32 *p;
733	__be32 status = res->csr_status;
734
735	if (unlikely(status != 0))
736		return status;
737
738	status = encode_sessionid(xdr, &res->csr_sessionid);
739	if (status)
740		return status;
741
742	p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
743	if (unlikely(p == NULL))
744		return htonl(NFS4ERR_RESOURCE);
745
746	*p++ = htonl(res->csr_sequenceid);
747	*p++ = htonl(res->csr_slotid);
748	*p++ = htonl(res->csr_highestslotid);
749	*p++ = htonl(res->csr_target_highestslotid);
750	return 0;
751}
752
753static __be32
754preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
755{
756	if (op_nr == OP_CB_SEQUENCE) {
757		if (nop != 0)
758			return htonl(NFS4ERR_SEQUENCE_POS);
759	} else {
760		if (nop == 0)
761			return htonl(NFS4ERR_OP_NOT_IN_SESSION);
762	}
763
764	switch (op_nr) {
765	case OP_CB_GETATTR:
766	case OP_CB_RECALL:
767	case OP_CB_SEQUENCE:
768	case OP_CB_RECALL_ANY:
769	case OP_CB_RECALL_SLOT:
770	case OP_CB_LAYOUTRECALL:
771	case OP_CB_NOTIFY_DEVICEID:
772	case OP_CB_NOTIFY_LOCK:
773		*op = &callback_ops[op_nr];
774		break;
775
776	case OP_CB_NOTIFY:
777	case OP_CB_PUSH_DELEG:
778	case OP_CB_RECALLABLE_OBJ_AVAIL:
779	case OP_CB_WANTS_CANCELLED:
780		return htonl(NFS4ERR_NOTSUPP);
781
782	default:
783		return htonl(NFS4ERR_OP_ILLEGAL);
784	}
785
786	return htonl(NFS_OK);
787}
788
789static void nfs4_callback_free_slot(struct nfs4_session *session,
790		struct nfs4_slot *slot)
791{
792	struct nfs4_slot_table *tbl = &session->bc_slot_table;
793
794	spin_lock(&tbl->slot_tbl_lock);
795	/*
796	 * Let the state manager know callback processing done.
797	 * A single slot, so highest used slotid is either 0 or -1
798	 */
799	nfs4_free_slot(tbl, slot);
800	spin_unlock(&tbl->slot_tbl_lock);
801}
802
803static void nfs4_cb_free_slot(struct cb_process_state *cps)
804{
805	if (cps->slot) {
806		nfs4_callback_free_slot(cps->clp->cl_session, cps->slot);
807		cps->slot = NULL;
808	}
809}
810
811#else /* CONFIG_NFS_V4_1 */
812
813static __be32
814preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
815{
816	return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
817}
818
819static void nfs4_cb_free_slot(struct cb_process_state *cps)
820{
821}
822#endif /* CONFIG_NFS_V4_1 */
823
824#ifdef CONFIG_NFS_V4_2
825static __be32
826preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
827{
828	__be32 status = preprocess_nfs41_op(nop, op_nr, op);
829	if (status != htonl(NFS4ERR_OP_ILLEGAL))
830		return status;
831
832	if (op_nr == OP_CB_OFFLOAD) {
833		*op = &callback_ops[op_nr];
834		return htonl(NFS_OK);
835	} else
836		return htonl(NFS4ERR_NOTSUPP);
837	return htonl(NFS4ERR_OP_ILLEGAL);
838}
839#else /* CONFIG_NFS_V4_2 */
840static __be32
841preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
842{
843	return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
844}
845#endif /* CONFIG_NFS_V4_2 */
846
847static __be32
848preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
849{
850	switch (op_nr) {
851	case OP_CB_GETATTR:
852	case OP_CB_RECALL:
853		*op = &callback_ops[op_nr];
854		break;
855	default:
856		return htonl(NFS4ERR_OP_ILLEGAL);
857	}
858
859	return htonl(NFS_OK);
860}
861
862static __be32 process_op(int nop, struct svc_rqst *rqstp,
863		struct xdr_stream *xdr_in, void *argp,
864		struct xdr_stream *xdr_out, void *resp,
865		struct cb_process_state *cps)
866{
867	struct callback_op *op = &callback_ops[0];
868	unsigned int op_nr;
869	__be32 status;
870	long maxlen;
871	__be32 res;
872
873	status = decode_op_hdr(xdr_in, &op_nr);
874	if (unlikely(status))
875		return status;
876
877	switch (cps->minorversion) {
878	case 0:
879		status = preprocess_nfs4_op(op_nr, &op);
880		break;
881	case 1:
882		status = preprocess_nfs41_op(nop, op_nr, &op);
883		break;
884	case 2:
885		status = preprocess_nfs42_op(nop, op_nr, &op);
886		break;
887	default:
888		status = htonl(NFS4ERR_MINOR_VERS_MISMATCH);
889	}
890
891	if (status == htonl(NFS4ERR_OP_ILLEGAL))
892		op_nr = OP_CB_ILLEGAL;
893	if (status)
894		goto encode_hdr;
895
896	if (cps->drc_status) {
897		status = cps->drc_status;
898		goto encode_hdr;
899	}
900
901	maxlen = xdr_out->end - xdr_out->p;
902	if (maxlen > 0 && maxlen < PAGE_SIZE) {
903		status = op->decode_args(rqstp, xdr_in, argp);
904		if (likely(status == 0))
905			status = op->process_op(argp, resp, cps);
906	} else
907		status = htonl(NFS4ERR_RESOURCE);
908
909encode_hdr:
910	res = encode_op_hdr(xdr_out, op_nr, status);
911	if (unlikely(res))
912		return res;
913	if (op->encode_res != NULL && status == 0)
914		status = op->encode_res(rqstp, xdr_out, resp);
915	return status;
916}
917
918/*
919 * Decode, process and encode a COMPOUND
920 */
921static __be32 nfs4_callback_compound(struct svc_rqst *rqstp)
922{
923	struct cb_compound_hdr_arg hdr_arg = { 0 };
924	struct cb_compound_hdr_res hdr_res = { NULL };
925	struct xdr_stream xdr_in, xdr_out;
926	__be32 *p, status;
927	struct cb_process_state cps = {
928		.drc_status = 0,
929		.clp = NULL,
930		.net = SVC_NET(rqstp),
931	};
932	unsigned int nops = 0;
933
934	xdr_init_decode(&xdr_in, &rqstp->rq_arg,
935			rqstp->rq_arg.head[0].iov_base, NULL);
936
937	p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
938	xdr_init_encode(&xdr_out, &rqstp->rq_res, p, NULL);
939
940	status = decode_compound_hdr_arg(&xdr_in, &hdr_arg);
941	if (status == htonl(NFS4ERR_RESOURCE))
942		return rpc_garbage_args;
943
944	if (hdr_arg.minorversion == 0) {
945		cps.clp = nfs4_find_client_ident(SVC_NET(rqstp), hdr_arg.cb_ident);
946		if (!cps.clp) {
947			trace_nfs_cb_no_clp(rqstp->rq_xid, hdr_arg.cb_ident);
948			goto out_invalidcred;
949		}
950		if (!check_gss_callback_principal(cps.clp, rqstp)) {
951			trace_nfs_cb_badprinc(rqstp->rq_xid, hdr_arg.cb_ident);
952			nfs_put_client(cps.clp);
953			goto out_invalidcred;
954		}
955	}
956
957	cps.minorversion = hdr_arg.minorversion;
958	hdr_res.taglen = hdr_arg.taglen;
959	hdr_res.tag = hdr_arg.tag;
960	if (encode_compound_hdr_res(&xdr_out, &hdr_res) != 0) {
961		if (cps.clp)
962			nfs_put_client(cps.clp);
963		return rpc_system_err;
964	}
965	while (status == 0 && nops != hdr_arg.nops) {
966		status = process_op(nops, rqstp, &xdr_in,
967				    rqstp->rq_argp, &xdr_out, rqstp->rq_resp,
968				    &cps);
969		nops++;
970	}
971
972	/* Buffer overflow in decode_ops_hdr or encode_ops_hdr. Return
973	* resource error in cb_compound status without returning op */
974	if (unlikely(status == htonl(NFS4ERR_RESOURCE_HDR))) {
975		status = htonl(NFS4ERR_RESOURCE);
976		nops--;
977	}
978
979	*hdr_res.status = status;
980	*hdr_res.nops = htonl(nops);
981	nfs4_cb_free_slot(&cps);
982	nfs_put_client(cps.clp);
983	return rpc_success;
984
985out_invalidcred:
986	pr_warn_ratelimited("NFS: NFSv4 callback contains invalid cred\n");
987	return svc_return_autherr(rqstp, rpc_autherr_badcred);
988}
989
990/*
991 * Define NFS4 callback COMPOUND ops.
992 */
993static struct callback_op callback_ops[] = {
994	[0] = {
995		.res_maxsize = CB_OP_HDR_RES_MAXSZ,
996	},
997	[OP_CB_GETATTR] = {
998		.process_op = nfs4_callback_getattr,
999		.decode_args = decode_getattr_args,
1000		.encode_res = encode_getattr_res,
1001		.res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
1002	},
1003	[OP_CB_RECALL] = {
1004		.process_op = nfs4_callback_recall,
1005		.decode_args = decode_recall_args,
1006		.res_maxsize = CB_OP_RECALL_RES_MAXSZ,
1007	},
1008#if defined(CONFIG_NFS_V4_1)
1009	[OP_CB_LAYOUTRECALL] = {
1010		.process_op = nfs4_callback_layoutrecall,
1011		.decode_args = decode_layoutrecall_args,
1012		.res_maxsize = CB_OP_LAYOUTRECALL_RES_MAXSZ,
1013	},
1014	[OP_CB_NOTIFY_DEVICEID] = {
1015		.process_op = nfs4_callback_devicenotify,
1016		.decode_args = decode_devicenotify_args,
1017		.res_maxsize = CB_OP_DEVICENOTIFY_RES_MAXSZ,
1018	},
1019	[OP_CB_SEQUENCE] = {
1020		.process_op = nfs4_callback_sequence,
1021		.decode_args = decode_cb_sequence_args,
1022		.encode_res = encode_cb_sequence_res,
1023		.res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
1024	},
1025	[OP_CB_RECALL_ANY] = {
1026		.process_op = nfs4_callback_recallany,
1027		.decode_args = decode_recallany_args,
1028		.res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
1029	},
1030	[OP_CB_RECALL_SLOT] = {
1031		.process_op = nfs4_callback_recallslot,
1032		.decode_args = decode_recallslot_args,
1033		.res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
1034	},
1035	[OP_CB_NOTIFY_LOCK] = {
1036		.process_op = nfs4_callback_notify_lock,
1037		.decode_args = decode_notify_lock_args,
1038		.res_maxsize = CB_OP_NOTIFY_LOCK_RES_MAXSZ,
1039	},
1040#endif /* CONFIG_NFS_V4_1 */
1041#ifdef CONFIG_NFS_V4_2
1042	[OP_CB_OFFLOAD] = {
1043		.process_op = nfs4_callback_offload,
1044		.decode_args = decode_offload_args,
1045		.res_maxsize = CB_OP_OFFLOAD_RES_MAXSZ,
1046	},
1047#endif /* CONFIG_NFS_V4_2 */
1048};
1049
1050/*
1051 * Define NFS4 callback procedures
1052 */
1053static const struct svc_procedure nfs4_callback_procedures1[] = {
1054	[CB_NULL] = {
1055		.pc_func = nfs4_callback_null,
1056		.pc_decode = nfs4_decode_void,
1057		.pc_encode = nfs4_encode_void,
1058		.pc_xdrressize = 1,
1059	},
1060	[CB_COMPOUND] = {
1061		.pc_func = nfs4_callback_compound,
1062		.pc_encode = nfs4_encode_void,
1063		.pc_argsize = 256,
1064		.pc_ressize = 256,
1065		.pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
1066	}
1067};
1068
1069static unsigned int nfs4_callback_count1[ARRAY_SIZE(nfs4_callback_procedures1)];
1070const struct svc_version nfs4_callback_version1 = {
1071	.vs_vers = 1,
1072	.vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1073	.vs_proc = nfs4_callback_procedures1,
1074	.vs_count = nfs4_callback_count1,
1075	.vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1076	.vs_dispatch = NULL,
1077	.vs_hidden = true,
1078	.vs_need_cong_ctrl = true,
1079};
1080
1081static unsigned int nfs4_callback_count4[ARRAY_SIZE(nfs4_callback_procedures1)];
1082const struct svc_version nfs4_callback_version4 = {
1083	.vs_vers = 4,
1084	.vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1085	.vs_proc = nfs4_callback_procedures1,
1086	.vs_count = nfs4_callback_count4,
1087	.vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1088	.vs_dispatch = NULL,
1089	.vs_hidden = true,
1090	.vs_need_cong_ctrl = true,
1091};
1092