1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * XDR standard data types and function declarations
4 *
5 * Copyright (C) 1995-1997 Olaf Kirch <okir@monad.swb.de>
6 *
7 * Based on:
8 * RFC 4506 "XDR: External Data Representation Standard", May 2006
9 */
10
11#ifndef _SUNRPC_XDR_H_
12#define _SUNRPC_XDR_H_
13
14#include <linux/uio.h>
15#include <asm/byteorder.h>
16#include <asm/unaligned.h>
17#include <linux/scatterlist.h>
18
19struct bio_vec;
20struct rpc_rqst;
21
22/*
23 * Size of an XDR encoding unit in bytes, i.e. 32 bits,
24 * as defined in Section 3 of RFC 4506. All encoded
25 * XDR data items are aligned on a boundary of 32 bits.
26 */
27#define XDR_UNIT sizeof(__be32)
28
29/*
30 * Buffer adjustment
31 */
32#define XDR_QUADLEN(l) (((l) + 3) >> 2)
33
34/*
35 * Generic opaque `network object.'
36 */
37#define XDR_MAX_NETOBJ 1024
38struct xdr_netobj {
39 unsigned int len;
40 u8 * data;
41};
42
43/*
44 * Basic structure for transmission/reception of a client XDR message.
45 * Features a header (for a linear buffer containing RPC headers
46 * and the data payload for short messages), and then an array of
47 * pages.
48 * The tail iovec allows you to append data after the page array. Its
49 * main interest is for appending padding to the pages in order to
50 * satisfy the int_32-alignment requirements in RFC1832.
51 *
52 * For the future, we might want to string several of these together
53 * in a list if anybody wants to make use of NFSv4 COMPOUND
54 * operations and/or has a need for scatter/gather involving pages.
55 */
56struct xdr_buf {
57 struct kvec head[1], /* RPC header + non-page data */
58 tail[1]; /* Appended after page data */
59
60 struct bio_vec *bvec;
61 struct page ** pages; /* Array of pages */
62 unsigned int page_base, /* Start of page data */
63 page_len, /* Length of page data */
64 flags; /* Flags for data disposition */
65#define XDRBUF_READ 0x01 /* target of file read */
66#define XDRBUF_WRITE 0x02 /* source of file write */
67#define XDRBUF_SPARSE_PAGES 0x04 /* Page array is sparse */
68
69 unsigned int buflen, /* Total length of storage buffer */
70 len; /* Length of XDR encoded message */
71};
72
73static inline void
74xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
75{
76 buf->head[0].iov_base = start;
77 buf->head[0].iov_len = len;
78 buf->tail[0].iov_len = 0;
79 buf->pages = NULL;
80 buf->page_len = 0;
81 buf->flags = 0;
82 buf->len = 0;
83 buf->buflen = len;
84}
85
86/*
87 * pre-xdr'ed macros.
88 */
89
90#define xdr_zero cpu_to_be32(0)
91#define xdr_one cpu_to_be32(1)
92#define xdr_two cpu_to_be32(2)
93
94#define rpc_auth_null cpu_to_be32(RPC_AUTH_NULL)
95#define rpc_auth_unix cpu_to_be32(RPC_AUTH_UNIX)
96#define rpc_auth_short cpu_to_be32(RPC_AUTH_SHORT)
97#define rpc_auth_gss cpu_to_be32(RPC_AUTH_GSS)
98#define rpc_auth_tls cpu_to_be32(RPC_AUTH_TLS)
99
100#define rpc_call cpu_to_be32(RPC_CALL)
101#define rpc_reply cpu_to_be32(RPC_REPLY)
102
103#define rpc_msg_accepted cpu_to_be32(RPC_MSG_ACCEPTED)
104
105#define rpc_success cpu_to_be32(RPC_SUCCESS)
106#define rpc_prog_unavail cpu_to_be32(RPC_PROG_UNAVAIL)
107#define rpc_prog_mismatch cpu_to_be32(RPC_PROG_MISMATCH)
108#define rpc_proc_unavail cpu_to_be32(RPC_PROC_UNAVAIL)
109#define rpc_garbage_args cpu_to_be32(RPC_GARBAGE_ARGS)
110#define rpc_system_err cpu_to_be32(RPC_SYSTEM_ERR)
111#define rpc_drop_reply cpu_to_be32(RPC_DROP_REPLY)
112
113#define rpc_mismatch cpu_to_be32(RPC_MISMATCH)
114#define rpc_auth_error cpu_to_be32(RPC_AUTH_ERROR)
115
116#define rpc_auth_ok cpu_to_be32(RPC_AUTH_OK)
117#define rpc_autherr_badcred cpu_to_be32(RPC_AUTH_BADCRED)
118#define rpc_autherr_rejectedcred cpu_to_be32(RPC_AUTH_REJECTEDCRED)
119#define rpc_autherr_badverf cpu_to_be32(RPC_AUTH_BADVERF)
120#define rpc_autherr_rejectedverf cpu_to_be32(RPC_AUTH_REJECTEDVERF)
121#define rpc_autherr_tooweak cpu_to_be32(RPC_AUTH_TOOWEAK)
122#define rpcsec_gsserr_credproblem cpu_to_be32(RPCSEC_GSS_CREDPROBLEM)
123#define rpcsec_gsserr_ctxproblem cpu_to_be32(RPCSEC_GSS_CTXPROBLEM)
124
125/*
126 * Miscellaneous XDR helper functions
127 */
128__be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int len);
129__be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int len);
130__be32 *xdr_encode_string(__be32 *p, const char *s);
131__be32 *xdr_decode_string_inplace(__be32 *p, char **sp, unsigned int *lenp,
132 unsigned int maxlen);
133__be32 *xdr_encode_netobj(__be32 *p, const struct xdr_netobj *);
134__be32 *xdr_decode_netobj(__be32 *p, struct xdr_netobj *);
135
136void xdr_inline_pages(struct xdr_buf *, unsigned int,
137 struct page **, unsigned int, unsigned int);
138void xdr_terminate_string(const struct xdr_buf *, const u32);
139size_t xdr_buf_pagecount(const struct xdr_buf *buf);
140int xdr_alloc_bvec(struct xdr_buf *buf, gfp_t gfp);
141void xdr_free_bvec(struct xdr_buf *buf);
142unsigned int xdr_buf_to_bvec(struct bio_vec *bvec, unsigned int bvec_size,
143 const struct xdr_buf *xdr);
144
145static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len)
146{
147 return xdr_encode_opaque(p, ptr: s, len);
148}
149
150/*
151 * Decode 64bit quantities (NFSv3 support)
152 */
153static inline __be32 *
154xdr_encode_hyper(__be32 *p, __u64 val)
155{
156 put_unaligned_be64(val, p);
157 return p + 2;
158}
159
160static inline __be32 *
161xdr_decode_hyper(__be32 *p, __u64 *valp)
162{
163 *valp = get_unaligned_be64(p);
164 return p + 2;
165}
166
167static inline __be32 *
168xdr_decode_opaque_fixed(__be32 *p, void *ptr, unsigned int len)
169{
170 memcpy(ptr, p, len);
171 return p + XDR_QUADLEN(len);
172}
173
174static inline void xdr_netobj_dup(struct xdr_netobj *dst,
175 struct xdr_netobj *src, gfp_t gfp_mask)
176{
177 dst->data = kmemdup(p: src->data, size: src->len, gfp: gfp_mask);
178 dst->len = src->len;
179}
180
181/*
182 * Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
183 */
184static inline int
185xdr_adjust_iovec(struct kvec *iov, __be32 *p)
186{
187 return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base);
188}
189
190/*
191 * XDR buffer helper functions
192 */
193extern void xdr_buf_from_iov(const struct kvec *, struct xdr_buf *);
194extern int xdr_buf_subsegment(const struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
195extern void xdr_buf_trim(struct xdr_buf *, unsigned int);
196extern int read_bytes_from_xdr_buf(const struct xdr_buf *, unsigned int, void *, unsigned int);
197extern int write_bytes_to_xdr_buf(const struct xdr_buf *, unsigned int, void *, unsigned int);
198
199extern int xdr_encode_word(const struct xdr_buf *, unsigned int, u32);
200extern int xdr_decode_word(const struct xdr_buf *, unsigned int, u32 *);
201
202struct xdr_array2_desc;
203typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
204struct xdr_array2_desc {
205 unsigned int elem_size;
206 unsigned int array_len;
207 unsigned int array_maxlen;
208 xdr_xcode_elem_t xcode;
209};
210
211extern int xdr_decode_array2(const struct xdr_buf *buf, unsigned int base,
212 struct xdr_array2_desc *desc);
213extern int xdr_encode_array2(const struct xdr_buf *buf, unsigned int base,
214 struct xdr_array2_desc *desc);
215extern void _copy_from_pages(char *p, struct page **pages, size_t pgbase,
216 size_t len);
217
218/*
219 * Provide some simple tools for XDR buffer overflow-checking etc.
220 */
221struct xdr_stream {
222 __be32 *p; /* start of available buffer */
223 struct xdr_buf *buf; /* XDR buffer to read/write */
224
225 __be32 *end; /* end of available buffer space */
226 struct kvec *iov; /* pointer to the current kvec */
227 struct kvec scratch; /* Scratch buffer */
228 struct page **page_ptr; /* pointer to the current page */
229 void *page_kaddr; /* kmapped address of the current page */
230 unsigned int nwords; /* Remaining decode buffer length */
231
232 struct rpc_rqst *rqst; /* For debugging */
233};
234
235/*
236 * These are the xdr_stream style generic XDR encode and decode functions.
237 */
238typedef void (*kxdreproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
239 const void *obj);
240typedef int (*kxdrdproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
241 void *obj);
242
243extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf,
244 __be32 *p, struct rpc_rqst *rqst);
245extern void xdr_init_encode_pages(struct xdr_stream *xdr, struct xdr_buf *buf,
246 struct page **pages, struct rpc_rqst *rqst);
247extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
248extern int xdr_reserve_space_vec(struct xdr_stream *xdr, size_t nbytes);
249extern void __xdr_commit_encode(struct xdr_stream *xdr);
250extern void xdr_truncate_encode(struct xdr_stream *xdr, size_t len);
251extern void xdr_truncate_decode(struct xdr_stream *xdr, size_t len);
252extern int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen);
253extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
254 unsigned int base, unsigned int len);
255extern unsigned int xdr_stream_pos(const struct xdr_stream *xdr);
256extern unsigned int xdr_page_pos(const struct xdr_stream *xdr);
257extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf,
258 __be32 *p, struct rpc_rqst *rqst);
259extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf,
260 struct page **pages, unsigned int len);
261extern void xdr_finish_decode(struct xdr_stream *xdr);
262extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
263extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
264extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
265extern int xdr_process_buf(const struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
266extern void xdr_set_pagelen(struct xdr_stream *, unsigned int len);
267extern bool xdr_stream_subsegment(struct xdr_stream *xdr, struct xdr_buf *subbuf,
268 unsigned int len);
269extern unsigned int xdr_stream_move_subsegment(struct xdr_stream *xdr, unsigned int offset,
270 unsigned int target, unsigned int length);
271extern unsigned int xdr_stream_zero(struct xdr_stream *xdr, unsigned int offset,
272 unsigned int length);
273
274/**
275 * xdr_set_scratch_buffer - Attach a scratch buffer for decoding data.
276 * @xdr: pointer to xdr_stream struct
277 * @buf: pointer to an empty buffer
278 * @buflen: size of 'buf'
279 *
280 * The scratch buffer is used when decoding from an array of pages.
281 * If an xdr_inline_decode() call spans across page boundaries, then
282 * we copy the data into the scratch buffer in order to allow linear
283 * access.
284 */
285static inline void
286xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen)
287{
288 xdr->scratch.iov_base = buf;
289 xdr->scratch.iov_len = buflen;
290}
291
292/**
293 * xdr_set_scratch_page - Attach a scratch buffer for decoding data
294 * @xdr: pointer to xdr_stream struct
295 * @page: an anonymous page
296 *
297 * See xdr_set_scratch_buffer().
298 */
299static inline void
300xdr_set_scratch_page(struct xdr_stream *xdr, struct page *page)
301{
302 xdr_set_scratch_buffer(xdr, page_address(page), PAGE_SIZE);
303}
304
305/**
306 * xdr_reset_scratch_buffer - Clear scratch buffer information
307 * @xdr: pointer to xdr_stream struct
308 *
309 * See xdr_set_scratch_buffer().
310 */
311static inline void
312xdr_reset_scratch_buffer(struct xdr_stream *xdr)
313{
314 xdr_set_scratch_buffer(xdr, NULL, buflen: 0);
315}
316
317/**
318 * xdr_commit_encode - Ensure all data is written to xdr->buf
319 * @xdr: pointer to xdr_stream
320 *
321 * Handle encoding across page boundaries by giving the caller a
322 * temporary location to write to, then later copying the data into
323 * place. __xdr_commit_encode() does that copying.
324 */
325static inline void xdr_commit_encode(struct xdr_stream *xdr)
326{
327 if (unlikely(xdr->scratch.iov_len))
328 __xdr_commit_encode(xdr);
329}
330
331/**
332 * xdr_stream_remaining - Return the number of bytes remaining in the stream
333 * @xdr: pointer to struct xdr_stream
334 *
335 * Return value:
336 * Number of bytes remaining in @xdr before xdr->end
337 */
338static inline size_t
339xdr_stream_remaining(const struct xdr_stream *xdr)
340{
341 return xdr->nwords << 2;
342}
343
344ssize_t xdr_stream_decode_opaque(struct xdr_stream *xdr, void *ptr,
345 size_t size);
346ssize_t xdr_stream_decode_opaque_dup(struct xdr_stream *xdr, void **ptr,
347 size_t maxlen, gfp_t gfp_flags);
348ssize_t xdr_stream_decode_string(struct xdr_stream *xdr, char *str,
349 size_t size);
350ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str,
351 size_t maxlen, gfp_t gfp_flags);
352ssize_t xdr_stream_decode_opaque_auth(struct xdr_stream *xdr, u32 *flavor,
353 void **body, unsigned int *body_len);
354ssize_t xdr_stream_encode_opaque_auth(struct xdr_stream *xdr, u32 flavor,
355 void *body, unsigned int body_len);
356
357/**
358 * xdr_align_size - Calculate padded size of an object
359 * @n: Size of an object being XDR encoded (in bytes)
360 *
361 * Return value:
362 * Size (in bytes) of the object including xdr padding
363 */
364static inline size_t
365xdr_align_size(size_t n)
366{
367 const size_t mask = XDR_UNIT - 1;
368
369 return (n + mask) & ~mask;
370}
371
372/**
373 * xdr_pad_size - Calculate size of an object's pad
374 * @n: Size of an object being XDR encoded (in bytes)
375 *
376 * This implementation avoids the need for conditional
377 * branches or modulo division.
378 *
379 * Return value:
380 * Size (in bytes) of the needed XDR pad
381 */
382static inline size_t xdr_pad_size(size_t n)
383{
384 return xdr_align_size(n) - n;
385}
386
387/**
388 * xdr_stream_encode_item_present - Encode a "present" list item
389 * @xdr: pointer to xdr_stream
390 *
391 * Return values:
392 * On success, returns length in bytes of XDR buffer consumed
393 * %-EMSGSIZE on XDR buffer overflow
394 */
395static inline ssize_t xdr_stream_encode_item_present(struct xdr_stream *xdr)
396{
397 const size_t len = XDR_UNIT;
398 __be32 *p = xdr_reserve_space(xdr, nbytes: len);
399
400 if (unlikely(!p))
401 return -EMSGSIZE;
402 *p = xdr_one;
403 return len;
404}
405
406/**
407 * xdr_stream_encode_item_absent - Encode a "not present" list item
408 * @xdr: pointer to xdr_stream
409 *
410 * Return values:
411 * On success, returns length in bytes of XDR buffer consumed
412 * %-EMSGSIZE on XDR buffer overflow
413 */
414static inline int xdr_stream_encode_item_absent(struct xdr_stream *xdr)
415{
416 const size_t len = XDR_UNIT;
417 __be32 *p = xdr_reserve_space(xdr, nbytes: len);
418
419 if (unlikely(!p))
420 return -EMSGSIZE;
421 *p = xdr_zero;
422 return len;
423}
424
425/**
426 * xdr_encode_bool - Encode a boolean item
427 * @p: address in a buffer into which to encode
428 * @n: boolean value to encode
429 *
430 * Return value:
431 * Address of item following the encoded boolean
432 */
433static inline __be32 *xdr_encode_bool(__be32 *p, u32 n)
434{
435 *p++ = n ? xdr_one : xdr_zero;
436 return p;
437}
438
439/**
440 * xdr_stream_encode_bool - Encode a boolean item
441 * @xdr: pointer to xdr_stream
442 * @n: boolean value to encode
443 *
444 * Return values:
445 * On success, returns length in bytes of XDR buffer consumed
446 * %-EMSGSIZE on XDR buffer overflow
447 */
448static inline int xdr_stream_encode_bool(struct xdr_stream *xdr, __u32 n)
449{
450 const size_t len = XDR_UNIT;
451 __be32 *p = xdr_reserve_space(xdr, nbytes: len);
452
453 if (unlikely(!p))
454 return -EMSGSIZE;
455 xdr_encode_bool(p, n);
456 return len;
457}
458
459/**
460 * xdr_stream_encode_u32 - Encode a 32-bit integer
461 * @xdr: pointer to xdr_stream
462 * @n: integer to encode
463 *
464 * Return values:
465 * On success, returns length in bytes of XDR buffer consumed
466 * %-EMSGSIZE on XDR buffer overflow
467 */
468static inline ssize_t
469xdr_stream_encode_u32(struct xdr_stream *xdr, __u32 n)
470{
471 const size_t len = sizeof(n);
472 __be32 *p = xdr_reserve_space(xdr, nbytes: len);
473
474 if (unlikely(!p))
475 return -EMSGSIZE;
476 *p = cpu_to_be32(n);
477 return len;
478}
479
480/**
481 * xdr_stream_encode_be32 - Encode a big-endian 32-bit integer
482 * @xdr: pointer to xdr_stream
483 * @n: integer to encode
484 *
485 * Return values:
486 * On success, returns length in bytes of XDR buffer consumed
487 * %-EMSGSIZE on XDR buffer overflow
488 */
489static inline ssize_t
490xdr_stream_encode_be32(struct xdr_stream *xdr, __be32 n)
491{
492 const size_t len = sizeof(n);
493 __be32 *p = xdr_reserve_space(xdr, nbytes: len);
494
495 if (unlikely(!p))
496 return -EMSGSIZE;
497 *p = n;
498 return len;
499}
500
501/**
502 * xdr_stream_encode_u64 - Encode a 64-bit integer
503 * @xdr: pointer to xdr_stream
504 * @n: 64-bit integer to encode
505 *
506 * Return values:
507 * On success, returns length in bytes of XDR buffer consumed
508 * %-EMSGSIZE on XDR buffer overflow
509 */
510static inline ssize_t
511xdr_stream_encode_u64(struct xdr_stream *xdr, __u64 n)
512{
513 const size_t len = sizeof(n);
514 __be32 *p = xdr_reserve_space(xdr, nbytes: len);
515
516 if (unlikely(!p))
517 return -EMSGSIZE;
518 xdr_encode_hyper(p, val: n);
519 return len;
520}
521
522/**
523 * xdr_stream_encode_opaque_inline - Encode opaque xdr data
524 * @xdr: pointer to xdr_stream
525 * @ptr: pointer to void pointer
526 * @len: size of object
527 *
528 * Return values:
529 * On success, returns length in bytes of XDR buffer consumed
530 * %-EMSGSIZE on XDR buffer overflow
531 */
532static inline ssize_t
533xdr_stream_encode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t len)
534{
535 size_t count = sizeof(__u32) + xdr_align_size(n: len);
536 __be32 *p = xdr_reserve_space(xdr, nbytes: count);
537
538 if (unlikely(!p)) {
539 *ptr = NULL;
540 return -EMSGSIZE;
541 }
542 xdr_encode_opaque(p, NULL, len);
543 *ptr = ++p;
544 return count;
545}
546
547/**
548 * xdr_stream_encode_opaque_fixed - Encode fixed length opaque xdr data
549 * @xdr: pointer to xdr_stream
550 * @ptr: pointer to opaque data object
551 * @len: size of object pointed to by @ptr
552 *
553 * Return values:
554 * On success, returns length in bytes of XDR buffer consumed
555 * %-EMSGSIZE on XDR buffer overflow
556 */
557static inline ssize_t
558xdr_stream_encode_opaque_fixed(struct xdr_stream *xdr, const void *ptr, size_t len)
559{
560 __be32 *p = xdr_reserve_space(xdr, nbytes: len);
561
562 if (unlikely(!p))
563 return -EMSGSIZE;
564 xdr_encode_opaque_fixed(p, ptr, len);
565 return xdr_align_size(n: len);
566}
567
568/**
569 * xdr_stream_encode_opaque - Encode variable length opaque xdr data
570 * @xdr: pointer to xdr_stream
571 * @ptr: pointer to opaque data object
572 * @len: size of object pointed to by @ptr
573 *
574 * Return values:
575 * On success, returns length in bytes of XDR buffer consumed
576 * %-EMSGSIZE on XDR buffer overflow
577 */
578static inline ssize_t
579xdr_stream_encode_opaque(struct xdr_stream *xdr, const void *ptr, size_t len)
580{
581 size_t count = sizeof(__u32) + xdr_align_size(n: len);
582 __be32 *p = xdr_reserve_space(xdr, nbytes: count);
583
584 if (unlikely(!p))
585 return -EMSGSIZE;
586 xdr_encode_opaque(p, ptr, len);
587 return count;
588}
589
590/**
591 * xdr_stream_encode_uint32_array - Encode variable length array of integers
592 * @xdr: pointer to xdr_stream
593 * @array: array of integers
594 * @array_size: number of elements in @array
595 *
596 * Return values:
597 * On success, returns length in bytes of XDR buffer consumed
598 * %-EMSGSIZE on XDR buffer overflow
599 */
600static inline ssize_t
601xdr_stream_encode_uint32_array(struct xdr_stream *xdr,
602 const __u32 *array, size_t array_size)
603{
604 ssize_t ret = (array_size+1) * sizeof(__u32);
605 __be32 *p = xdr_reserve_space(xdr, nbytes: ret);
606
607 if (unlikely(!p))
608 return -EMSGSIZE;
609 *p++ = cpu_to_be32(array_size);
610 for (; array_size > 0; p++, array++, array_size--)
611 *p = cpu_to_be32p(p: array);
612 return ret;
613}
614
615/**
616 * xdr_item_is_absent - symbolically handle XDR discriminators
617 * @p: pointer to undecoded discriminator
618 *
619 * Return values:
620 * %true if the following XDR item is absent
621 * %false if the following XDR item is present
622 */
623static inline bool xdr_item_is_absent(const __be32 *p)
624{
625 return *p == xdr_zero;
626}
627
628/**
629 * xdr_item_is_present - symbolically handle XDR discriminators
630 * @p: pointer to undecoded discriminator
631 *
632 * Return values:
633 * %true if the following XDR item is present
634 * %false if the following XDR item is absent
635 */
636static inline bool xdr_item_is_present(const __be32 *p)
637{
638 return *p != xdr_zero;
639}
640
641/**
642 * xdr_stream_decode_bool - Decode a boolean
643 * @xdr: pointer to xdr_stream
644 * @ptr: pointer to a u32 in which to store the result
645 *
646 * Return values:
647 * %0 on success
648 * %-EBADMSG on XDR buffer overflow
649 */
650static inline ssize_t
651xdr_stream_decode_bool(struct xdr_stream *xdr, __u32 *ptr)
652{
653 const size_t count = sizeof(*ptr);
654 __be32 *p = xdr_inline_decode(xdr, nbytes: count);
655
656 if (unlikely(!p))
657 return -EBADMSG;
658 *ptr = (*p != xdr_zero);
659 return 0;
660}
661
662/**
663 * xdr_stream_decode_u32 - Decode a 32-bit integer
664 * @xdr: pointer to xdr_stream
665 * @ptr: location to store integer
666 *
667 * Return values:
668 * %0 on success
669 * %-EBADMSG on XDR buffer overflow
670 */
671static inline ssize_t
672xdr_stream_decode_u32(struct xdr_stream *xdr, __u32 *ptr)
673{
674 const size_t count = sizeof(*ptr);
675 __be32 *p = xdr_inline_decode(xdr, nbytes: count);
676
677 if (unlikely(!p))
678 return -EBADMSG;
679 *ptr = be32_to_cpup(p);
680 return 0;
681}
682
683/**
684 * xdr_stream_decode_u64 - Decode a 64-bit integer
685 * @xdr: pointer to xdr_stream
686 * @ptr: location to store 64-bit integer
687 *
688 * Return values:
689 * %0 on success
690 * %-EBADMSG on XDR buffer overflow
691 */
692static inline ssize_t
693xdr_stream_decode_u64(struct xdr_stream *xdr, __u64 *ptr)
694{
695 const size_t count = sizeof(*ptr);
696 __be32 *p = xdr_inline_decode(xdr, nbytes: count);
697
698 if (unlikely(!p))
699 return -EBADMSG;
700 xdr_decode_hyper(p, valp: ptr);
701 return 0;
702}
703
704/**
705 * xdr_stream_decode_opaque_fixed - Decode fixed length opaque xdr data
706 * @xdr: pointer to xdr_stream
707 * @ptr: location to store data
708 * @len: size of buffer pointed to by @ptr
709 *
710 * Return values:
711 * On success, returns size of object stored in @ptr
712 * %-EBADMSG on XDR buffer overflow
713 */
714static inline ssize_t
715xdr_stream_decode_opaque_fixed(struct xdr_stream *xdr, void *ptr, size_t len)
716{
717 __be32 *p = xdr_inline_decode(xdr, nbytes: len);
718
719 if (unlikely(!p))
720 return -EBADMSG;
721 xdr_decode_opaque_fixed(p, ptr, len);
722 return len;
723}
724
725/**
726 * xdr_stream_decode_opaque_inline - Decode variable length opaque xdr data
727 * @xdr: pointer to xdr_stream
728 * @ptr: location to store pointer to opaque data
729 * @maxlen: maximum acceptable object size
730 *
731 * Note: the pointer stored in @ptr cannot be assumed valid after the XDR
732 * buffer has been destroyed, or even after calling xdr_inline_decode()
733 * on @xdr. It is therefore expected that the object it points to should
734 * be processed immediately.
735 *
736 * Return values:
737 * On success, returns size of object stored in *@ptr
738 * %-EBADMSG on XDR buffer overflow
739 * %-EMSGSIZE if the size of the object would exceed @maxlen
740 */
741static inline ssize_t
742xdr_stream_decode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t maxlen)
743{
744 __be32 *p;
745 __u32 len;
746
747 *ptr = NULL;
748 if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0))
749 return -EBADMSG;
750 if (len != 0) {
751 p = xdr_inline_decode(xdr, nbytes: len);
752 if (unlikely(!p))
753 return -EBADMSG;
754 if (unlikely(len > maxlen))
755 return -EMSGSIZE;
756 *ptr = p;
757 }
758 return len;
759}
760
761/**
762 * xdr_stream_decode_uint32_array - Decode variable length array of integers
763 * @xdr: pointer to xdr_stream
764 * @array: location to store the integer array or NULL
765 * @array_size: number of elements to store
766 *
767 * Return values:
768 * On success, returns number of elements stored in @array
769 * %-EBADMSG on XDR buffer overflow
770 * %-EMSGSIZE if the size of the array exceeds @array_size
771 */
772static inline ssize_t
773xdr_stream_decode_uint32_array(struct xdr_stream *xdr,
774 __u32 *array, size_t array_size)
775{
776 __be32 *p;
777 __u32 len;
778 ssize_t retval;
779
780 if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0))
781 return -EBADMSG;
782 if (U32_MAX >= SIZE_MAX / sizeof(*p) && len > SIZE_MAX / sizeof(*p))
783 return -EBADMSG;
784 p = xdr_inline_decode(xdr, nbytes: len * sizeof(*p));
785 if (unlikely(!p))
786 return -EBADMSG;
787 if (array == NULL)
788 return len;
789 if (len <= array_size) {
790 if (len < array_size)
791 memset(array+len, 0, (array_size-len)*sizeof(*array));
792 array_size = len;
793 retval = len;
794 } else
795 retval = -EMSGSIZE;
796 for (; array_size > 0; p++, array++, array_size--)
797 *array = be32_to_cpup(p);
798 return retval;
799}
800
801#endif /* _SUNRPC_XDR_H_ */
802

source code of linux/include/linux/sunrpc/xdr.h