1/*
2 * linux/fs/nfs/callback_xdr.c
3 *
4 * Copyright (C) 2004 Trond Myklebust
5 *
6 * NFSv4 callback encode/decode procedures
7 */
8#include <linux/kernel.h>
9#include <linux/sunrpc/svc.h>
10#include <linux/nfs4.h>
11#include <linux/nfs_fs.h>
12#include <linux/ratelimit.h>
13#include <linux/printk.h>
14#include <linux/slab.h>
15#include <linux/sunrpc/bc_xprt.h>
16#include "nfs4_fs.h"
17#include "callback.h"
18#include "internal.h"
19#include "nfs4session.h"
20
21#define CB_OP_TAGLEN_MAXSZ		(512)
22#define CB_OP_HDR_RES_MAXSZ		(2 * 4) // opcode, status
23#define CB_OP_GETATTR_BITMAP_MAXSZ	(4 * 4) // bitmap length, 3 bitmaps
24#define CB_OP_GETATTR_RES_MAXSZ		(CB_OP_HDR_RES_MAXSZ + \
25					 CB_OP_GETATTR_BITMAP_MAXSZ + \
26					 /* change, size, ctime, mtime */\
27					 (2 + 2 + 3 + 3) * 4)
28#define CB_OP_RECALL_RES_MAXSZ		(CB_OP_HDR_RES_MAXSZ)
29
30#if defined(CONFIG_NFS_V4_1)
31#define CB_OP_LAYOUTRECALL_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
32#define CB_OP_DEVICENOTIFY_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
33#define CB_OP_SEQUENCE_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ + \
34					 NFS4_MAX_SESSIONID_LEN + \
35					 (1 + 3) * 4) // seqid, 3 slotids
36#define CB_OP_RECALLANY_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
37#define CB_OP_RECALLSLOT_RES_MAXSZ	(CB_OP_HDR_RES_MAXSZ)
38#endif /* CONFIG_NFS_V4_1 */
39
40#define NFSDBG_FACILITY NFSDBG_CALLBACK
41
42/* Internal error code */
43#define NFS4ERR_RESOURCE_HDR	11050
44
45typedef __be32 (*callback_process_op_t)(void *, void *,
46					struct cb_process_state *);
47typedef __be32 (*callback_decode_arg_t)(struct svc_rqst *, struct xdr_stream *, void *);
48typedef __be32 (*callback_encode_res_t)(struct svc_rqst *, struct xdr_stream *, void *);
49
50
51struct callback_op {
52	callback_process_op_t process_op;
53	callback_decode_arg_t decode_args;
54	callback_encode_res_t encode_res;
55	long res_maxsize;
56};
57
58static struct callback_op callback_ops[];
59
60static __be32 nfs4_callback_null(struct svc_rqst *rqstp, void *argp, void *resp)
61{
62	return htonl(NFS4_OK);
63}
64
65static int nfs4_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
66{
67	return xdr_argsize_check(rqstp, p);
68}
69
70static int nfs4_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
71{
72	return xdr_ressize_check(rqstp, p);
73}
74
75static __be32 *read_buf(struct xdr_stream *xdr, int nbytes)
76{
77	__be32 *p;
78
79	p = xdr_inline_decode(xdr, nbytes);
80	if (unlikely(p == NULL))
81		printk(KERN_WARNING "NFS: NFSv4 callback reply buffer overflowed!\n");
82	return p;
83}
84
85static __be32 decode_string(struct xdr_stream *xdr, unsigned int *len, const char **str)
86{
87	__be32 *p;
88
89	p = read_buf(xdr, 4);
90	if (unlikely(p == NULL))
91		return htonl(NFS4ERR_RESOURCE);
92	*len = ntohl(*p);
93
94	if (*len != 0) {
95		p = read_buf(xdr, *len);
96		if (unlikely(p == NULL))
97			return htonl(NFS4ERR_RESOURCE);
98		*str = (const char *)p;
99	} else
100		*str = NULL;
101
102	return 0;
103}
104
105static __be32 decode_fh(struct xdr_stream *xdr, struct nfs_fh *fh)
106{
107	__be32 *p;
108
109	p = read_buf(xdr, 4);
110	if (unlikely(p == NULL))
111		return htonl(NFS4ERR_RESOURCE);
112	fh->size = ntohl(*p);
113	if (fh->size > NFS4_FHSIZE)
114		return htonl(NFS4ERR_BADHANDLE);
115	p = read_buf(xdr, fh->size);
116	if (unlikely(p == NULL))
117		return htonl(NFS4ERR_RESOURCE);
118	memcpy(&fh->data[0], p, fh->size);
119	memset(&fh->data[fh->size], 0, sizeof(fh->data) - fh->size);
120	return 0;
121}
122
123static __be32 decode_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
124{
125	__be32 *p;
126	unsigned int attrlen;
127
128	p = read_buf(xdr, 4);
129	if (unlikely(p == NULL))
130		return htonl(NFS4ERR_RESOURCE);
131	attrlen = ntohl(*p);
132	p = read_buf(xdr, attrlen << 2);
133	if (unlikely(p == NULL))
134		return htonl(NFS4ERR_RESOURCE);
135	if (likely(attrlen > 0))
136		bitmap[0] = ntohl(*p++);
137	if (attrlen > 1)
138		bitmap[1] = ntohl(*p);
139	return 0;
140}
141
142static __be32 decode_stateid(struct xdr_stream *xdr, nfs4_stateid *stateid)
143{
144	__be32 *p;
145
146	p = read_buf(xdr, NFS4_STATEID_SIZE);
147	if (unlikely(p == NULL))
148		return htonl(NFS4ERR_RESOURCE);
149	memcpy(stateid, p, NFS4_STATEID_SIZE);
150	return 0;
151}
152
153static __be32 decode_compound_hdr_arg(struct xdr_stream *xdr, struct cb_compound_hdr_arg *hdr)
154{
155	__be32 *p;
156	__be32 status;
157
158	status = decode_string(xdr, &hdr->taglen, &hdr->tag);
159	if (unlikely(status != 0))
160		return status;
161	/* We do not like overly long tags! */
162	if (hdr->taglen > CB_OP_TAGLEN_MAXSZ) {
163		printk("NFS: NFSv4 CALLBACK %s: client sent tag of length %u\n",
164				__func__, hdr->taglen);
165		return htonl(NFS4ERR_RESOURCE);
166	}
167	p = read_buf(xdr, 12);
168	if (unlikely(p == NULL))
169		return htonl(NFS4ERR_RESOURCE);
170	hdr->minorversion = ntohl(*p++);
171	/* Check for minor version support */
172	if (hdr->minorversion <= NFS4_MAX_MINOR_VERSION) {
173		hdr->cb_ident = ntohl(*p++); /* ignored by v4.1 and v4.2 */
174	} else {
175		pr_warn_ratelimited("NFS: %s: NFSv4 server callback with "
176			"illegal minor version %u!\n",
177			__func__, hdr->minorversion);
178		return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
179	}
180	hdr->nops = ntohl(*p);
181	dprintk("%s: minorversion %d nops %d\n", __func__,
182		hdr->minorversion, hdr->nops);
183	return 0;
184}
185
186static __be32 decode_op_hdr(struct xdr_stream *xdr, unsigned int *op)
187{
188	__be32 *p;
189	p = read_buf(xdr, 4);
190	if (unlikely(p == NULL))
191		return htonl(NFS4ERR_RESOURCE_HDR);
192	*op = ntohl(*p);
193	return 0;
194}
195
196static __be32 decode_getattr_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_getattrargs *args)
197{
198	__be32 status;
199
200	status = decode_fh(xdr, &args->fh);
201	if (unlikely(status != 0))
202		goto out;
203	status = decode_bitmap(xdr, args->bitmap);
204out:
205	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
206	return status;
207}
208
209static __be32 decode_recall_args(struct svc_rqst *rqstp, struct xdr_stream *xdr, struct cb_recallargs *args)
210{
211	__be32 *p;
212	__be32 status;
213
214	status = decode_stateid(xdr, &args->stateid);
215	if (unlikely(status != 0))
216		goto out;
217	p = read_buf(xdr, 4);
218	if (unlikely(p == NULL)) {
219		status = htonl(NFS4ERR_RESOURCE);
220		goto out;
221	}
222	args->truncate = ntohl(*p);
223	status = decode_fh(xdr, &args->fh);
224out:
225	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
226	return status;
227}
228
229#if defined(CONFIG_NFS_V4_1)
230
231static __be32 decode_layoutrecall_args(struct svc_rqst *rqstp,
232				       struct xdr_stream *xdr,
233				       struct cb_layoutrecallargs *args)
234{
235	__be32 *p;
236	__be32 status = 0;
237	uint32_t iomode;
238
239	p = read_buf(xdr, 4 * sizeof(uint32_t));
240	if (unlikely(p == NULL)) {
241		status = htonl(NFS4ERR_BADXDR);
242		goto out;
243	}
244
245	args->cbl_layout_type = ntohl(*p++);
246	/* Depite the spec's xdr, iomode really belongs in the FILE switch,
247	 * as it is unusable and ignored with the other types.
248	 */
249	iomode = ntohl(*p++);
250	args->cbl_layoutchanged = ntohl(*p++);
251	args->cbl_recall_type = ntohl(*p++);
252
253	if (args->cbl_recall_type == RETURN_FILE) {
254		args->cbl_range.iomode = iomode;
255		status = decode_fh(xdr, &args->cbl_fh);
256		if (unlikely(status != 0))
257			goto out;
258
259		p = read_buf(xdr, 2 * sizeof(uint64_t));
260		if (unlikely(p == NULL)) {
261			status = htonl(NFS4ERR_BADXDR);
262			goto out;
263		}
264		p = xdr_decode_hyper(p, &args->cbl_range.offset);
265		p = xdr_decode_hyper(p, &args->cbl_range.length);
266		status = decode_stateid(xdr, &args->cbl_stateid);
267		if (unlikely(status != 0))
268			goto out;
269	} else if (args->cbl_recall_type == RETURN_FSID) {
270		p = read_buf(xdr, 2 * sizeof(uint64_t));
271		if (unlikely(p == NULL)) {
272			status = htonl(NFS4ERR_BADXDR);
273			goto out;
274		}
275		p = xdr_decode_hyper(p, &args->cbl_fsid.major);
276		p = xdr_decode_hyper(p, &args->cbl_fsid.minor);
277	} else if (args->cbl_recall_type != RETURN_ALL) {
278		status = htonl(NFS4ERR_BADXDR);
279		goto out;
280	}
281	dprintk("%s: ltype 0x%x iomode %d changed %d recall_type %d\n",
282		__func__,
283		args->cbl_layout_type, iomode,
284		args->cbl_layoutchanged, args->cbl_recall_type);
285out:
286	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
287	return status;
288}
289
290static
291__be32 decode_devicenotify_args(struct svc_rqst *rqstp,
292				struct xdr_stream *xdr,
293				struct cb_devicenotifyargs *args)
294{
295	__be32 *p;
296	__be32 status = 0;
297	u32 tmp;
298	int n, i;
299	args->ndevs = 0;
300
301	/* Num of device notifications */
302	p = read_buf(xdr, sizeof(uint32_t));
303	if (unlikely(p == NULL)) {
304		status = htonl(NFS4ERR_BADXDR);
305		goto out;
306	}
307	n = ntohl(*p++);
308	if (n <= 0)
309		goto out;
310	if (n > ULONG_MAX / sizeof(*args->devs)) {
311		status = htonl(NFS4ERR_BADXDR);
312		goto out;
313	}
314
315	args->devs = kmalloc_array(n, sizeof(*args->devs), GFP_KERNEL);
316	if (!args->devs) {
317		status = htonl(NFS4ERR_DELAY);
318		goto out;
319	}
320
321	/* Decode each dev notification */
322	for (i = 0; i < n; i++) {
323		struct cb_devicenotifyitem *dev = &args->devs[i];
324
325		p = read_buf(xdr, (4 * sizeof(uint32_t)) + NFS4_DEVICEID4_SIZE);
326		if (unlikely(p == NULL)) {
327			status = htonl(NFS4ERR_BADXDR);
328			goto err;
329		}
330
331		tmp = ntohl(*p++);	/* bitmap size */
332		if (tmp != 1) {
333			status = htonl(NFS4ERR_INVAL);
334			goto err;
335		}
336		dev->cbd_notify_type = ntohl(*p++);
337		if (dev->cbd_notify_type != NOTIFY_DEVICEID4_CHANGE &&
338		    dev->cbd_notify_type != NOTIFY_DEVICEID4_DELETE) {
339			status = htonl(NFS4ERR_INVAL);
340			goto err;
341		}
342
343		tmp = ntohl(*p++);	/* opaque size */
344		if (((dev->cbd_notify_type == NOTIFY_DEVICEID4_CHANGE) &&
345		     (tmp != NFS4_DEVICEID4_SIZE + 8)) ||
346		    ((dev->cbd_notify_type == NOTIFY_DEVICEID4_DELETE) &&
347		     (tmp != NFS4_DEVICEID4_SIZE + 4))) {
348			status = htonl(NFS4ERR_INVAL);
349			goto err;
350		}
351		dev->cbd_layout_type = ntohl(*p++);
352		memcpy(dev->cbd_dev_id.data, p, NFS4_DEVICEID4_SIZE);
353		p += XDR_QUADLEN(NFS4_DEVICEID4_SIZE);
354
355		if (dev->cbd_layout_type == NOTIFY_DEVICEID4_CHANGE) {
356			p = read_buf(xdr, sizeof(uint32_t));
357			if (unlikely(p == NULL)) {
358				status = htonl(NFS4ERR_BADXDR);
359				goto err;
360			}
361			dev->cbd_immediate = ntohl(*p++);
362		} else {
363			dev->cbd_immediate = 0;
364		}
365
366		args->ndevs++;
367
368		dprintk("%s: type %d layout 0x%x immediate %d\n",
369			__func__, dev->cbd_notify_type, dev->cbd_layout_type,
370			dev->cbd_immediate);
371	}
372out:
373	dprintk("%s: status %d ndevs %d\n",
374		__func__, ntohl(status), args->ndevs);
375	return status;
376err:
377	kfree(args->devs);
378	goto out;
379}
380
381static __be32 decode_sessionid(struct xdr_stream *xdr,
382				 struct nfs4_sessionid *sid)
383{
384	__be32 *p;
385
386	p = read_buf(xdr, NFS4_MAX_SESSIONID_LEN);
387	if (unlikely(p == NULL))
388		return htonl(NFS4ERR_RESOURCE);
389
390	memcpy(sid->data, p, NFS4_MAX_SESSIONID_LEN);
391	return 0;
392}
393
394static __be32 decode_rc_list(struct xdr_stream *xdr,
395			       struct referring_call_list *rc_list)
396{
397	__be32 *p;
398	int i;
399	__be32 status;
400
401	status = decode_sessionid(xdr, &rc_list->rcl_sessionid);
402	if (status)
403		goto out;
404
405	status = htonl(NFS4ERR_RESOURCE);
406	p = read_buf(xdr, sizeof(uint32_t));
407	if (unlikely(p == NULL))
408		goto out;
409
410	rc_list->rcl_nrefcalls = ntohl(*p++);
411	if (rc_list->rcl_nrefcalls) {
412		p = read_buf(xdr,
413			     rc_list->rcl_nrefcalls * 2 * sizeof(uint32_t));
414		if (unlikely(p == NULL))
415			goto out;
416		rc_list->rcl_refcalls = kmalloc_array(rc_list->rcl_nrefcalls,
417						sizeof(*rc_list->rcl_refcalls),
418						GFP_KERNEL);
419		if (unlikely(rc_list->rcl_refcalls == NULL))
420			goto out;
421		for (i = 0; i < rc_list->rcl_nrefcalls; i++) {
422			rc_list->rcl_refcalls[i].rc_sequenceid = ntohl(*p++);
423			rc_list->rcl_refcalls[i].rc_slotid = ntohl(*p++);
424		}
425	}
426	status = 0;
427
428out:
429	return status;
430}
431
432static __be32 decode_cb_sequence_args(struct svc_rqst *rqstp,
433					struct xdr_stream *xdr,
434					struct cb_sequenceargs *args)
435{
436	__be32 *p;
437	int i;
438	__be32 status;
439
440	status = decode_sessionid(xdr, &args->csa_sessionid);
441	if (status)
442		goto out;
443
444	status = htonl(NFS4ERR_RESOURCE);
445	p = read_buf(xdr, 5 * sizeof(uint32_t));
446	if (unlikely(p == NULL))
447		goto out;
448
449	args->csa_addr = svc_addr(rqstp);
450	args->csa_sequenceid = ntohl(*p++);
451	args->csa_slotid = ntohl(*p++);
452	args->csa_highestslotid = ntohl(*p++);
453	args->csa_cachethis = ntohl(*p++);
454	args->csa_nrclists = ntohl(*p++);
455	args->csa_rclists = NULL;
456	if (args->csa_nrclists) {
457		args->csa_rclists = kmalloc_array(args->csa_nrclists,
458						  sizeof(*args->csa_rclists),
459						  GFP_KERNEL);
460		if (unlikely(args->csa_rclists == NULL))
461			goto out;
462
463		for (i = 0; i < args->csa_nrclists; i++) {
464			status = decode_rc_list(xdr, &args->csa_rclists[i]);
465			if (status) {
466				args->csa_nrclists = i;
467				goto out_free;
468			}
469		}
470	}
471	status = 0;
472
473	dprintk("%s: sessionid %x:%x:%x:%x sequenceid %u slotid %u "
474		"highestslotid %u cachethis %d nrclists %u\n",
475		__func__,
476		((u32 *)&args->csa_sessionid)[0],
477		((u32 *)&args->csa_sessionid)[1],
478		((u32 *)&args->csa_sessionid)[2],
479		((u32 *)&args->csa_sessionid)[3],
480		args->csa_sequenceid, args->csa_slotid,
481		args->csa_highestslotid, args->csa_cachethis,
482		args->csa_nrclists);
483out:
484	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
485	return status;
486
487out_free:
488	for (i = 0; i < args->csa_nrclists; i++)
489		kfree(args->csa_rclists[i].rcl_refcalls);
490	kfree(args->csa_rclists);
491	goto out;
492}
493
494static __be32 decode_recallany_args(struct svc_rqst *rqstp,
495				      struct xdr_stream *xdr,
496				      struct cb_recallanyargs *args)
497{
498	uint32_t bitmap[2];
499	__be32 *p, status;
500
501	p = read_buf(xdr, 4);
502	if (unlikely(p == NULL))
503		return htonl(NFS4ERR_BADXDR);
504	args->craa_objs_to_keep = ntohl(*p++);
505	status = decode_bitmap(xdr, bitmap);
506	if (unlikely(status))
507		return status;
508	args->craa_type_mask = bitmap[0];
509
510	return 0;
511}
512
513static __be32 decode_recallslot_args(struct svc_rqst *rqstp,
514					struct xdr_stream *xdr,
515					struct cb_recallslotargs *args)
516{
517	__be32 *p;
518
519	p = read_buf(xdr, 4);
520	if (unlikely(p == NULL))
521		return htonl(NFS4ERR_BADXDR);
522	args->crsa_target_highest_slotid = ntohl(*p++);
523	return 0;
524}
525
526#endif /* CONFIG_NFS_V4_1 */
527
528static __be32 encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
529{
530	__be32 *p;
531
532	p = xdr_reserve_space(xdr, 4 + len);
533	if (unlikely(p == NULL))
534		return htonl(NFS4ERR_RESOURCE);
535	xdr_encode_opaque(p, str, len);
536	return 0;
537}
538
539#define CB_SUPPORTED_ATTR0 (FATTR4_WORD0_CHANGE|FATTR4_WORD0_SIZE)
540#define CB_SUPPORTED_ATTR1 (FATTR4_WORD1_TIME_METADATA|FATTR4_WORD1_TIME_MODIFY)
541static __be32 encode_attr_bitmap(struct xdr_stream *xdr, const uint32_t *bitmap, __be32 **savep)
542{
543	__be32 bm[2];
544	__be32 *p;
545
546	bm[0] = htonl(bitmap[0] & CB_SUPPORTED_ATTR0);
547	bm[1] = htonl(bitmap[1] & CB_SUPPORTED_ATTR1);
548	if (bm[1] != 0) {
549		p = xdr_reserve_space(xdr, 16);
550		if (unlikely(p == NULL))
551			return htonl(NFS4ERR_RESOURCE);
552		*p++ = htonl(2);
553		*p++ = bm[0];
554		*p++ = bm[1];
555	} else if (bm[0] != 0) {
556		p = xdr_reserve_space(xdr, 12);
557		if (unlikely(p == NULL))
558			return htonl(NFS4ERR_RESOURCE);
559		*p++ = htonl(1);
560		*p++ = bm[0];
561	} else {
562		p = xdr_reserve_space(xdr, 8);
563		if (unlikely(p == NULL))
564			return htonl(NFS4ERR_RESOURCE);
565		*p++ = htonl(0);
566	}
567	*savep = p;
568	return 0;
569}
570
571static __be32 encode_attr_change(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t change)
572{
573	__be32 *p;
574
575	if (!(bitmap[0] & FATTR4_WORD0_CHANGE))
576		return 0;
577	p = xdr_reserve_space(xdr, 8);
578	if (unlikely(!p))
579		return htonl(NFS4ERR_RESOURCE);
580	p = xdr_encode_hyper(p, change);
581	return 0;
582}
583
584static __be32 encode_attr_size(struct xdr_stream *xdr, const uint32_t *bitmap, uint64_t size)
585{
586	__be32 *p;
587
588	if (!(bitmap[0] & FATTR4_WORD0_SIZE))
589		return 0;
590	p = xdr_reserve_space(xdr, 8);
591	if (unlikely(!p))
592		return htonl(NFS4ERR_RESOURCE);
593	p = xdr_encode_hyper(p, size);
594	return 0;
595}
596
597static __be32 encode_attr_time(struct xdr_stream *xdr, const struct timespec *time)
598{
599	__be32 *p;
600
601	p = xdr_reserve_space(xdr, 12);
602	if (unlikely(!p))
603		return htonl(NFS4ERR_RESOURCE);
604	p = xdr_encode_hyper(p, time->tv_sec);
605	*p = htonl(time->tv_nsec);
606	return 0;
607}
608
609static __be32 encode_attr_ctime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
610{
611	if (!(bitmap[1] & FATTR4_WORD1_TIME_METADATA))
612		return 0;
613	return encode_attr_time(xdr,time);
614}
615
616static __be32 encode_attr_mtime(struct xdr_stream *xdr, const uint32_t *bitmap, const struct timespec *time)
617{
618	if (!(bitmap[1] & FATTR4_WORD1_TIME_MODIFY))
619		return 0;
620	return encode_attr_time(xdr,time);
621}
622
623static __be32 encode_compound_hdr_res(struct xdr_stream *xdr, struct cb_compound_hdr_res *hdr)
624{
625	__be32 status;
626
627	hdr->status = xdr_reserve_space(xdr, 4);
628	if (unlikely(hdr->status == NULL))
629		return htonl(NFS4ERR_RESOURCE);
630	status = encode_string(xdr, hdr->taglen, hdr->tag);
631	if (unlikely(status != 0))
632		return status;
633	hdr->nops = xdr_reserve_space(xdr, 4);
634	if (unlikely(hdr->nops == NULL))
635		return htonl(NFS4ERR_RESOURCE);
636	return 0;
637}
638
639static __be32 encode_op_hdr(struct xdr_stream *xdr, uint32_t op, __be32 res)
640{
641	__be32 *p;
642
643	p = xdr_reserve_space(xdr, 8);
644	if (unlikely(p == NULL))
645		return htonl(NFS4ERR_RESOURCE_HDR);
646	*p++ = htonl(op);
647	*p = res;
648	return 0;
649}
650
651static __be32 encode_getattr_res(struct svc_rqst *rqstp, struct xdr_stream *xdr, const struct cb_getattrres *res)
652{
653	__be32 *savep = NULL;
654	__be32 status = res->status;
655
656	if (unlikely(status != 0))
657		goto out;
658	status = encode_attr_bitmap(xdr, res->bitmap, &savep);
659	if (unlikely(status != 0))
660		goto out;
661	status = encode_attr_change(xdr, res->bitmap, res->change_attr);
662	if (unlikely(status != 0))
663		goto out;
664	status = encode_attr_size(xdr, res->bitmap, res->size);
665	if (unlikely(status != 0))
666		goto out;
667	status = encode_attr_ctime(xdr, res->bitmap, &res->ctime);
668	if (unlikely(status != 0))
669		goto out;
670	status = encode_attr_mtime(xdr, res->bitmap, &res->mtime);
671	*savep = htonl((unsigned int)((char *)xdr->p - (char *)(savep+1)));
672out:
673	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
674	return status;
675}
676
677#if defined(CONFIG_NFS_V4_1)
678
679static __be32 encode_sessionid(struct xdr_stream *xdr,
680				 const struct nfs4_sessionid *sid)
681{
682	__be32 *p;
683
684	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN);
685	if (unlikely(p == NULL))
686		return htonl(NFS4ERR_RESOURCE);
687
688	memcpy(p, sid, NFS4_MAX_SESSIONID_LEN);
689	return 0;
690}
691
692static __be32 encode_cb_sequence_res(struct svc_rqst *rqstp,
693				       struct xdr_stream *xdr,
694				       const struct cb_sequenceres *res)
695{
696	__be32 *p;
697	__be32 status = res->csr_status;
698
699	if (unlikely(status != 0))
700		goto out;
701
702	status = encode_sessionid(xdr, &res->csr_sessionid);
703	if (status)
704		goto out;
705
706	p = xdr_reserve_space(xdr, 4 * sizeof(uint32_t));
707	if (unlikely(p == NULL))
708		return htonl(NFS4ERR_RESOURCE);
709
710	*p++ = htonl(res->csr_sequenceid);
711	*p++ = htonl(res->csr_slotid);
712	*p++ = htonl(res->csr_highestslotid);
713	*p++ = htonl(res->csr_target_highestslotid);
714out:
715	dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
716	return status;
717}
718
719static __be32
720preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
721{
722	if (op_nr == OP_CB_SEQUENCE) {
723		if (nop != 0)
724			return htonl(NFS4ERR_SEQUENCE_POS);
725	} else {
726		if (nop == 0)
727			return htonl(NFS4ERR_OP_NOT_IN_SESSION);
728	}
729
730	switch (op_nr) {
731	case OP_CB_GETATTR:
732	case OP_CB_RECALL:
733	case OP_CB_SEQUENCE:
734	case OP_CB_RECALL_ANY:
735	case OP_CB_RECALL_SLOT:
736	case OP_CB_LAYOUTRECALL:
737	case OP_CB_NOTIFY_DEVICEID:
738		*op = &callback_ops[op_nr];
739		break;
740
741	case OP_CB_NOTIFY:
742	case OP_CB_PUSH_DELEG:
743	case OP_CB_RECALLABLE_OBJ_AVAIL:
744	case OP_CB_WANTS_CANCELLED:
745	case OP_CB_NOTIFY_LOCK:
746		return htonl(NFS4ERR_NOTSUPP);
747
748	default:
749		return htonl(NFS4ERR_OP_ILLEGAL);
750	}
751
752	return htonl(NFS_OK);
753}
754
755static void nfs4_callback_free_slot(struct nfs4_session *session)
756{
757	struct nfs4_slot_table *tbl = &session->bc_slot_table;
758
759	spin_lock(&tbl->slot_tbl_lock);
760	/*
761	 * Let the state manager know callback processing done.
762	 * A single slot, so highest used slotid is either 0 or -1
763	 */
764	tbl->highest_used_slotid = NFS4_NO_SLOT;
765	nfs4_slot_tbl_drain_complete(tbl);
766	spin_unlock(&tbl->slot_tbl_lock);
767}
768
769static void nfs4_cb_free_slot(struct cb_process_state *cps)
770{
771	if (cps->slotid != NFS4_NO_SLOT)
772		nfs4_callback_free_slot(cps->clp->cl_session);
773}
774
775#else /* CONFIG_NFS_V4_1 */
776
777static __be32
778preprocess_nfs41_op(int nop, unsigned int op_nr, struct callback_op **op)
779{
780	return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
781}
782
783static void nfs4_cb_free_slot(struct cb_process_state *cps)
784{
785}
786#endif /* CONFIG_NFS_V4_1 */
787
788#ifdef CONFIG_NFS_V4_2
789static __be32
790preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
791{
792	__be32 status = preprocess_nfs41_op(nop, op_nr, op);
793	if (status != htonl(NFS4ERR_OP_ILLEGAL))
794		return status;
795
796	if (op_nr == OP_CB_OFFLOAD)
797		return htonl(NFS4ERR_NOTSUPP);
798	return htonl(NFS4ERR_OP_ILLEGAL);
799}
800#else /* CONFIG_NFS_V4_2 */
801static __be32
802preprocess_nfs42_op(int nop, unsigned int op_nr, struct callback_op **op)
803{
804	return htonl(NFS4ERR_MINOR_VERS_MISMATCH);
805}
806#endif /* CONFIG_NFS_V4_2 */
807
808static __be32
809preprocess_nfs4_op(unsigned int op_nr, struct callback_op **op)
810{
811	switch (op_nr) {
812	case OP_CB_GETATTR:
813	case OP_CB_RECALL:
814		*op = &callback_ops[op_nr];
815		break;
816	default:
817		return htonl(NFS4ERR_OP_ILLEGAL);
818	}
819
820	return htonl(NFS_OK);
821}
822
823static __be32 process_op(int nop, struct svc_rqst *rqstp,
824		struct xdr_stream *xdr_in, void *argp,
825		struct xdr_stream *xdr_out, void *resp,
826		struct cb_process_state *cps)
827{
828	struct callback_op *op = &callback_ops[0];
829	unsigned int op_nr;
830	__be32 status;
831	long maxlen;
832	__be32 res;
833
834	dprintk("%s: start\n", __func__);
835	status = decode_op_hdr(xdr_in, &op_nr);
836	if (unlikely(status))
837		return status;
838
839	dprintk("%s: minorversion=%d nop=%d op_nr=%u\n",
840		__func__, cps->minorversion, nop, op_nr);
841
842	switch (cps->minorversion) {
843	case 0:
844		status = preprocess_nfs4_op(op_nr, &op);
845		break;
846	case 1:
847		status = preprocess_nfs41_op(nop, op_nr, &op);
848		break;
849	case 2:
850		status = preprocess_nfs42_op(nop, op_nr, &op);
851		break;
852	default:
853		status = htonl(NFS4ERR_MINOR_VERS_MISMATCH);
854	}
855
856	if (status == htonl(NFS4ERR_OP_ILLEGAL))
857		op_nr = OP_CB_ILLEGAL;
858	if (status)
859		goto encode_hdr;
860
861	if (cps->drc_status) {
862		status = cps->drc_status;
863		goto encode_hdr;
864	}
865
866	maxlen = xdr_out->end - xdr_out->p;
867	if (maxlen > 0 && maxlen < PAGE_SIZE) {
868		status = op->decode_args(rqstp, xdr_in, argp);
869		if (likely(status == 0))
870			status = op->process_op(argp, resp, cps);
871	} else
872		status = htonl(NFS4ERR_RESOURCE);
873
874encode_hdr:
875	res = encode_op_hdr(xdr_out, op_nr, status);
876	if (unlikely(res))
877		return res;
878	if (op->encode_res != NULL && status == 0)
879		status = op->encode_res(rqstp, xdr_out, resp);
880	dprintk("%s: done, status = %d\n", __func__, ntohl(status));
881	return status;
882}
883
884/*
885 * Decode, process and encode a COMPOUND
886 */
887static __be32 nfs4_callback_compound(struct svc_rqst *rqstp, void *argp, void *resp)
888{
889	struct cb_compound_hdr_arg hdr_arg = { 0 };
890	struct cb_compound_hdr_res hdr_res = { NULL };
891	struct xdr_stream xdr_in, xdr_out;
892	__be32 *p, status;
893	struct cb_process_state cps = {
894		.drc_status = 0,
895		.clp = NULL,
896		.slotid = NFS4_NO_SLOT,
897		.net = SVC_NET(rqstp),
898	};
899	unsigned int nops = 0;
900
901	dprintk("%s: start\n", __func__);
902
903	xdr_init_decode(&xdr_in, &rqstp->rq_arg, rqstp->rq_arg.head[0].iov_base);
904
905	p = (__be32*)((char *)rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len);
906	xdr_init_encode(&xdr_out, &rqstp->rq_res, p);
907
908	status = decode_compound_hdr_arg(&xdr_in, &hdr_arg);
909	if (status == htonl(NFS4ERR_RESOURCE))
910		return rpc_garbage_args;
911
912	if (hdr_arg.minorversion == 0) {
913		cps.clp = nfs4_find_client_ident(SVC_NET(rqstp), hdr_arg.cb_ident);
914		if (!cps.clp || !check_gss_callback_principal(cps.clp, rqstp))
915			return rpc_drop_reply;
916	}
917
918	cps.minorversion = hdr_arg.minorversion;
919	hdr_res.taglen = hdr_arg.taglen;
920	hdr_res.tag = hdr_arg.tag;
921	if (encode_compound_hdr_res(&xdr_out, &hdr_res) != 0)
922		return rpc_system_err;
923
924	while (status == 0 && nops != hdr_arg.nops) {
925		status = process_op(nops, rqstp, &xdr_in,
926				    argp, &xdr_out, resp, &cps);
927		nops++;
928	}
929
930	/* Buffer overflow in decode_ops_hdr or encode_ops_hdr. Return
931	* resource error in cb_compound status without returning op */
932	if (unlikely(status == htonl(NFS4ERR_RESOURCE_HDR))) {
933		status = htonl(NFS4ERR_RESOURCE);
934		nops--;
935	}
936
937	*hdr_res.status = status;
938	*hdr_res.nops = htonl(nops);
939	nfs4_cb_free_slot(&cps);
940	nfs_put_client(cps.clp);
941	dprintk("%s: done, status = %u\n", __func__, ntohl(status));
942	return rpc_success;
943}
944
945/*
946 * Define NFS4 callback COMPOUND ops.
947 */
948static struct callback_op callback_ops[] = {
949	[0] = {
950		.res_maxsize = CB_OP_HDR_RES_MAXSZ,
951	},
952	[OP_CB_GETATTR] = {
953		.process_op = (callback_process_op_t)nfs4_callback_getattr,
954		.decode_args = (callback_decode_arg_t)decode_getattr_args,
955		.encode_res = (callback_encode_res_t)encode_getattr_res,
956		.res_maxsize = CB_OP_GETATTR_RES_MAXSZ,
957	},
958	[OP_CB_RECALL] = {
959		.process_op = (callback_process_op_t)nfs4_callback_recall,
960		.decode_args = (callback_decode_arg_t)decode_recall_args,
961		.res_maxsize = CB_OP_RECALL_RES_MAXSZ,
962	},
963#if defined(CONFIG_NFS_V4_1)
964	[OP_CB_LAYOUTRECALL] = {
965		.process_op = (callback_process_op_t)nfs4_callback_layoutrecall,
966		.decode_args =
967			(callback_decode_arg_t)decode_layoutrecall_args,
968		.res_maxsize = CB_OP_LAYOUTRECALL_RES_MAXSZ,
969	},
970	[OP_CB_NOTIFY_DEVICEID] = {
971		.process_op = (callback_process_op_t)nfs4_callback_devicenotify,
972		.decode_args =
973			(callback_decode_arg_t)decode_devicenotify_args,
974		.res_maxsize = CB_OP_DEVICENOTIFY_RES_MAXSZ,
975	},
976	[OP_CB_SEQUENCE] = {
977		.process_op = (callback_process_op_t)nfs4_callback_sequence,
978		.decode_args = (callback_decode_arg_t)decode_cb_sequence_args,
979		.encode_res = (callback_encode_res_t)encode_cb_sequence_res,
980		.res_maxsize = CB_OP_SEQUENCE_RES_MAXSZ,
981	},
982	[OP_CB_RECALL_ANY] = {
983		.process_op = (callback_process_op_t)nfs4_callback_recallany,
984		.decode_args = (callback_decode_arg_t)decode_recallany_args,
985		.res_maxsize = CB_OP_RECALLANY_RES_MAXSZ,
986	},
987	[OP_CB_RECALL_SLOT] = {
988		.process_op = (callback_process_op_t)nfs4_callback_recallslot,
989		.decode_args = (callback_decode_arg_t)decode_recallslot_args,
990		.res_maxsize = CB_OP_RECALLSLOT_RES_MAXSZ,
991	},
992#endif /* CONFIG_NFS_V4_1 */
993};
994
995/*
996 * Define NFS4 callback procedures
997 */
998static struct svc_procedure nfs4_callback_procedures1[] = {
999	[CB_NULL] = {
1000		.pc_func = nfs4_callback_null,
1001		.pc_decode = (kxdrproc_t)nfs4_decode_void,
1002		.pc_encode = (kxdrproc_t)nfs4_encode_void,
1003		.pc_xdrressize = 1,
1004	},
1005	[CB_COMPOUND] = {
1006		.pc_func = nfs4_callback_compound,
1007		.pc_encode = (kxdrproc_t)nfs4_encode_void,
1008		.pc_argsize = 256,
1009		.pc_ressize = 256,
1010		.pc_xdrressize = NFS4_CALLBACK_BUFSIZE,
1011	}
1012};
1013
1014struct svc_version nfs4_callback_version1 = {
1015	.vs_vers = 1,
1016	.vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1017	.vs_proc = nfs4_callback_procedures1,
1018	.vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1019	.vs_dispatch = NULL,
1020	.vs_hidden = 1,
1021};
1022
1023struct svc_version nfs4_callback_version4 = {
1024	.vs_vers = 4,
1025	.vs_nproc = ARRAY_SIZE(nfs4_callback_procedures1),
1026	.vs_proc = nfs4_callback_procedures1,
1027	.vs_xdrsize = NFS4_CALLBACK_XDRSIZE,
1028	.vs_dispatch = NULL,
1029	.vs_hidden = 1,
1030};
1031