1 /* SPDX-License-Identifier: GPL-2.0 */
3 * XDR standard data types and function declarations
5 * Copyright (C) 1995-1997 Olaf Kirch <okir@monad.swb.de>
8 * RFC 4506 "XDR: External Data Representation Standard", May 2006
11 #ifndef _SUNRPC_XDR_H_
12 #define _SUNRPC_XDR_H_
14 #include <linux/uio.h>
15 #include <asm/byteorder.h>
16 #include <asm/unaligned.h>
17 #include <linux/scatterlist.h>
25 #define XDR_QUADLEN(l) (((l) + 3) >> 2)
28 * Generic opaque `network object.' At the kernel level, this type
29 * is used only by lockd.
31 #define XDR_MAX_NETOBJ 1024
38 * Basic structure for transmission/reception of a client XDR message.
39 * Features a header (for a linear buffer containing RPC headers
40 * and the data payload for short messages), and then an array of
42 * The tail iovec allows you to append data after the page array. Its
43 * main interest is for appending padding to the pages in order to
44 * satisfy the int_32-alignment requirements in RFC1832.
46 * For the future, we might want to string several of these together
47 * in a list if anybody wants to make use of NFSv4 COMPOUND
48 * operations and/or has a need for scatter/gather involving pages.
51 struct kvec head[1], /* RPC header + non-page data */
52 tail[1]; /* Appended after page data */
55 struct page ** pages; /* Array of pages */
56 unsigned int page_base, /* Start of page data */
57 page_len, /* Length of page data */
58 flags; /* Flags for data disposition */
59 #define XDRBUF_READ 0x01 /* target of file read */
60 #define XDRBUF_WRITE 0x02 /* source of file write */
61 #define XDRBUF_SPARSE_PAGES 0x04 /* Page array is sparse */
63 unsigned int buflen, /* Total length of storage buffer */
64 len; /* Length of XDR encoded message */
68 xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
70 buf->head[0].iov_base = start;
71 buf->head[0].iov_len = len;
72 buf->tail[0].iov_len = 0;
84 #define xdr_zero cpu_to_be32(0)
85 #define xdr_one cpu_to_be32(1)
86 #define xdr_two cpu_to_be32(2)
88 #define rpc_auth_null cpu_to_be32(RPC_AUTH_NULL)
89 #define rpc_auth_unix cpu_to_be32(RPC_AUTH_UNIX)
90 #define rpc_auth_short cpu_to_be32(RPC_AUTH_SHORT)
91 #define rpc_auth_gss cpu_to_be32(RPC_AUTH_GSS)
93 #define rpc_call cpu_to_be32(RPC_CALL)
94 #define rpc_reply cpu_to_be32(RPC_REPLY)
96 #define rpc_msg_accepted cpu_to_be32(RPC_MSG_ACCEPTED)
98 #define rpc_success cpu_to_be32(RPC_SUCCESS)
99 #define rpc_prog_unavail cpu_to_be32(RPC_PROG_UNAVAIL)
100 #define rpc_prog_mismatch cpu_to_be32(RPC_PROG_MISMATCH)
101 #define rpc_proc_unavail cpu_to_be32(RPC_PROC_UNAVAIL)
102 #define rpc_garbage_args cpu_to_be32(RPC_GARBAGE_ARGS)
103 #define rpc_system_err cpu_to_be32(RPC_SYSTEM_ERR)
104 #define rpc_drop_reply cpu_to_be32(RPC_DROP_REPLY)
106 #define rpc_mismatch cpu_to_be32(RPC_MISMATCH)
107 #define rpc_auth_error cpu_to_be32(RPC_AUTH_ERROR)
109 #define rpc_auth_ok cpu_to_be32(RPC_AUTH_OK)
110 #define rpc_autherr_badcred cpu_to_be32(RPC_AUTH_BADCRED)
111 #define rpc_autherr_rejectedcred cpu_to_be32(RPC_AUTH_REJECTEDCRED)
112 #define rpc_autherr_badverf cpu_to_be32(RPC_AUTH_BADVERF)
113 #define rpc_autherr_rejectedverf cpu_to_be32(RPC_AUTH_REJECTEDVERF)
114 #define rpc_autherr_tooweak cpu_to_be32(RPC_AUTH_TOOWEAK)
115 #define rpcsec_gsserr_credproblem cpu_to_be32(RPCSEC_GSS_CREDPROBLEM)
116 #define rpcsec_gsserr_ctxproblem cpu_to_be32(RPCSEC_GSS_CTXPROBLEM)
119 * Miscellaneous XDR helper functions
121 __be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int len);
122 __be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int len);
123 __be32 *xdr_encode_string(__be32 *p, const char *s);
124 __be32 *xdr_decode_string_inplace(__be32 *p, char **sp, unsigned int *lenp,
125 unsigned int maxlen);
126 __be32 *xdr_encode_netobj(__be32 *p, const struct xdr_netobj *);
127 __be32 *xdr_decode_netobj(__be32 *p, struct xdr_netobj *);
129 void xdr_inline_pages(struct xdr_buf *, unsigned int,
130 struct page **, unsigned int, unsigned int);
131 void xdr_terminate_string(struct xdr_buf *, const u32);
132 size_t xdr_buf_pagecount(struct xdr_buf *buf);
133 int xdr_alloc_bvec(struct xdr_buf *buf, gfp_t gfp);
134 void xdr_free_bvec(struct xdr_buf *buf);
136 static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len)
138 return xdr_encode_opaque(p, s, len);
142 * Decode 64bit quantities (NFSv3 support)
144 static inline __be32 *
145 xdr_encode_hyper(__be32 *p, __u64 val)
147 put_unaligned_be64(val, p);
151 static inline __be32 *
152 xdr_decode_hyper(__be32 *p, __u64 *valp)
154 *valp = get_unaligned_be64(p);
158 static inline __be32 *
159 xdr_decode_opaque_fixed(__be32 *p, void *ptr, unsigned int len)
162 return p + XDR_QUADLEN(len);
165 static inline void xdr_netobj_dup(struct xdr_netobj *dst,
166 struct xdr_netobj *src, gfp_t gfp_mask)
168 dst->data = kmemdup(src->data, src->len, gfp_mask);
173 * Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
176 xdr_adjust_iovec(struct kvec *iov, __be32 *p)
178 return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base);
182 * XDR buffer helper functions
184 extern void xdr_shift_buf(struct xdr_buf *, size_t);
185 extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *);
186 extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
187 extern void xdr_buf_trim(struct xdr_buf *, unsigned int);
188 extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
189 extern int write_bytes_to_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
191 extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32);
192 extern int xdr_decode_word(struct xdr_buf *, unsigned int, u32 *);
194 struct xdr_array2_desc;
195 typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
196 struct xdr_array2_desc {
197 unsigned int elem_size;
198 unsigned int array_len;
199 unsigned int array_maxlen;
200 xdr_xcode_elem_t xcode;
203 extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
204 struct xdr_array2_desc *desc);
205 extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
206 struct xdr_array2_desc *desc);
207 extern void _copy_from_pages(char *p, struct page **pages, size_t pgbase,
211 * Provide some simple tools for XDR buffer overflow-checking etc.
214 __be32 *p; /* start of available buffer */
215 struct xdr_buf *buf; /* XDR buffer to read/write */
217 __be32 *end; /* end of available buffer space */
218 struct kvec *iov; /* pointer to the current kvec */
219 struct kvec scratch; /* Scratch buffer */
220 struct page **page_ptr; /* pointer to the current page */
221 unsigned int nwords; /* Remaining decode buffer length */
223 struct rpc_rqst *rqst; /* For debugging */
227 * These are the xdr_stream style generic XDR encode and decode functions.
229 typedef void (*kxdreproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
231 typedef int (*kxdrdproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
234 extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf,
235 __be32 *p, struct rpc_rqst *rqst);
236 extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
237 extern void xdr_commit_encode(struct xdr_stream *xdr);
238 extern void xdr_truncate_encode(struct xdr_stream *xdr, size_t len);
239 extern int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen);
240 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
241 unsigned int base, unsigned int len);
242 extern unsigned int xdr_stream_pos(const struct xdr_stream *xdr);
243 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf,
244 __be32 *p, struct rpc_rqst *rqst);
245 extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf,
246 struct page **pages, unsigned int len);
247 extern void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen);
248 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
249 extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
250 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
251 extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
254 * xdr_stream_remaining - Return the number of bytes remaining in the stream
255 * @xdr: pointer to struct xdr_stream
258 * Number of bytes remaining in @xdr before xdr->end
261 xdr_stream_remaining(const struct xdr_stream *xdr)
263 return xdr->nwords << 2;
266 ssize_t xdr_stream_decode_opaque(struct xdr_stream *xdr, void *ptr,
268 ssize_t xdr_stream_decode_opaque_dup(struct xdr_stream *xdr, void **ptr,
269 size_t maxlen, gfp_t gfp_flags);
270 ssize_t xdr_stream_decode_string(struct xdr_stream *xdr, char *str,
272 ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str,
273 size_t maxlen, gfp_t gfp_flags);
275 * xdr_align_size - Calculate padded size of an object
276 * @n: Size of an object being XDR encoded (in bytes)
279 * Size (in bytes) of the object including xdr padding
282 xdr_align_size(size_t n)
284 const size_t mask = sizeof(__u32) - 1;
286 return (n + mask) & ~mask;
290 * xdr_pad_size - Calculate size of an object's pad
291 * @n: Size of an object being XDR encoded (in bytes)
293 * This implementation avoids the need for conditional
294 * branches or modulo division.
297 * Size (in bytes) of the needed XDR pad
299 static inline size_t xdr_pad_size(size_t n)
301 return xdr_align_size(n) - n;
305 * xdr_stream_encode_item_present - Encode a "present" list item
306 * @xdr: pointer to xdr_stream
309 * On success, returns length in bytes of XDR buffer consumed
310 * %-EMSGSIZE on XDR buffer overflow
312 static inline ssize_t xdr_stream_encode_item_present(struct xdr_stream *xdr)
314 const size_t len = sizeof(__be32);
315 __be32 *p = xdr_reserve_space(xdr, len);
324 * xdr_stream_encode_item_absent - Encode a "not present" list item
325 * @xdr: pointer to xdr_stream
328 * On success, returns length in bytes of XDR buffer consumed
329 * %-EMSGSIZE on XDR buffer overflow
331 static inline int xdr_stream_encode_item_absent(struct xdr_stream *xdr)
333 const size_t len = sizeof(__be32);
334 __be32 *p = xdr_reserve_space(xdr, len);
343 * xdr_stream_encode_u32 - Encode a 32-bit integer
344 * @xdr: pointer to xdr_stream
345 * @n: integer to encode
348 * On success, returns length in bytes of XDR buffer consumed
349 * %-EMSGSIZE on XDR buffer overflow
351 static inline ssize_t
352 xdr_stream_encode_u32(struct xdr_stream *xdr, __u32 n)
354 const size_t len = sizeof(n);
355 __be32 *p = xdr_reserve_space(xdr, len);
364 * xdr_stream_encode_u64 - Encode a 64-bit integer
365 * @xdr: pointer to xdr_stream
366 * @n: 64-bit integer to encode
369 * On success, returns length in bytes of XDR buffer consumed
370 * %-EMSGSIZE on XDR buffer overflow
372 static inline ssize_t
373 xdr_stream_encode_u64(struct xdr_stream *xdr, __u64 n)
375 const size_t len = sizeof(n);
376 __be32 *p = xdr_reserve_space(xdr, len);
380 xdr_encode_hyper(p, n);
385 * xdr_stream_encode_opaque_inline - Encode opaque xdr data
386 * @xdr: pointer to xdr_stream
387 * @ptr: pointer to void pointer
388 * @len: size of object
391 * On success, returns length in bytes of XDR buffer consumed
392 * %-EMSGSIZE on XDR buffer overflow
394 static inline ssize_t
395 xdr_stream_encode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t len)
397 size_t count = sizeof(__u32) + xdr_align_size(len);
398 __be32 *p = xdr_reserve_space(xdr, count);
404 xdr_encode_opaque(p, NULL, len);
410 * xdr_stream_encode_opaque_fixed - Encode fixed length opaque xdr data
411 * @xdr: pointer to xdr_stream
412 * @ptr: pointer to opaque data object
413 * @len: size of object pointed to by @ptr
416 * On success, returns length in bytes of XDR buffer consumed
417 * %-EMSGSIZE on XDR buffer overflow
419 static inline ssize_t
420 xdr_stream_encode_opaque_fixed(struct xdr_stream *xdr, const void *ptr, size_t len)
422 __be32 *p = xdr_reserve_space(xdr, len);
426 xdr_encode_opaque_fixed(p, ptr, len);
427 return xdr_align_size(len);
431 * xdr_stream_encode_opaque - Encode variable length opaque xdr data
432 * @xdr: pointer to xdr_stream
433 * @ptr: pointer to opaque data object
434 * @len: size of object pointed to by @ptr
437 * On success, returns length in bytes of XDR buffer consumed
438 * %-EMSGSIZE on XDR buffer overflow
440 static inline ssize_t
441 xdr_stream_encode_opaque(struct xdr_stream *xdr, const void *ptr, size_t len)
443 size_t count = sizeof(__u32) + xdr_align_size(len);
444 __be32 *p = xdr_reserve_space(xdr, count);
448 xdr_encode_opaque(p, ptr, len);
453 * xdr_stream_encode_uint32_array - Encode variable length array of integers
454 * @xdr: pointer to xdr_stream
455 * @array: array of integers
456 * @array_size: number of elements in @array
459 * On success, returns length in bytes of XDR buffer consumed
460 * %-EMSGSIZE on XDR buffer overflow
462 static inline ssize_t
463 xdr_stream_encode_uint32_array(struct xdr_stream *xdr,
464 const __u32 *array, size_t array_size)
466 ssize_t ret = (array_size+1) * sizeof(__u32);
467 __be32 *p = xdr_reserve_space(xdr, ret);
471 *p++ = cpu_to_be32(array_size);
472 for (; array_size > 0; p++, array++, array_size--)
473 *p = cpu_to_be32p(array);
478 * xdr_item_is_absent - symbolically handle XDR discriminators
479 * @p: pointer to undecoded discriminator
482 * %true if the following XDR item is absent
483 * %false if the following XDR item is present
485 static inline bool xdr_item_is_absent(const __be32 *p)
487 return *p == xdr_zero;
491 * xdr_item_is_present - symbolically handle XDR discriminators
492 * @p: pointer to undecoded discriminator
495 * %true if the following XDR item is present
496 * %false if the following XDR item is absent
498 static inline bool xdr_item_is_present(const __be32 *p)
500 return *p != xdr_zero;
504 * xdr_stream_decode_u32 - Decode a 32-bit integer
505 * @xdr: pointer to xdr_stream
506 * @ptr: location to store integer
510 * %-EBADMSG on XDR buffer overflow
512 static inline ssize_t
513 xdr_stream_decode_u32(struct xdr_stream *xdr, __u32 *ptr)
515 const size_t count = sizeof(*ptr);
516 __be32 *p = xdr_inline_decode(xdr, count);
520 *ptr = be32_to_cpup(p);
525 * xdr_stream_decode_opaque_fixed - Decode fixed length opaque xdr data
526 * @xdr: pointer to xdr_stream
527 * @ptr: location to store data
528 * @len: size of buffer pointed to by @ptr
531 * On success, returns size of object stored in @ptr
532 * %-EBADMSG on XDR buffer overflow
534 static inline ssize_t
535 xdr_stream_decode_opaque_fixed(struct xdr_stream *xdr, void *ptr, size_t len)
537 __be32 *p = xdr_inline_decode(xdr, len);
541 xdr_decode_opaque_fixed(p, ptr, len);
546 * xdr_stream_decode_opaque_inline - Decode variable length opaque xdr data
547 * @xdr: pointer to xdr_stream
548 * @ptr: location to store pointer to opaque data
549 * @maxlen: maximum acceptable object size
551 * Note: the pointer stored in @ptr cannot be assumed valid after the XDR
552 * buffer has been destroyed, or even after calling xdr_inline_decode()
553 * on @xdr. It is therefore expected that the object it points to should
554 * be processed immediately.
557 * On success, returns size of object stored in *@ptr
558 * %-EBADMSG on XDR buffer overflow
559 * %-EMSGSIZE if the size of the object would exceed @maxlen
561 static inline ssize_t
562 xdr_stream_decode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t maxlen)
568 if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0))
571 p = xdr_inline_decode(xdr, len);
574 if (unlikely(len > maxlen))
582 * xdr_stream_decode_uint32_array - Decode variable length array of integers
583 * @xdr: pointer to xdr_stream
584 * @array: location to store the integer array or NULL
585 * @array_size: number of elements to store
588 * On success, returns number of elements stored in @array
589 * %-EBADMSG on XDR buffer overflow
590 * %-EMSGSIZE if the size of the array exceeds @array_size
592 static inline ssize_t
593 xdr_stream_decode_uint32_array(struct xdr_stream *xdr,
594 __u32 *array, size_t array_size)
600 if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0))
602 p = xdr_inline_decode(xdr, len * sizeof(*p));
607 if (len <= array_size) {
608 if (len < array_size)
609 memset(array+len, 0, (array_size-len)*sizeof(*array));
614 for (; array_size > 0; p++, array++, array_size--)
615 *array = be32_to_cpup(p);
619 #endif /* _SUNRPC_XDR_H_ */