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_
16 #include <linux/uio.h>
17 #include <asm/byteorder.h>
18 #include <asm/unaligned.h>
19 #include <linux/scatterlist.h>
27 #define XDR_QUADLEN(l) (((l) + 3) >> 2)
30 * Generic opaque `network object.' At the kernel level, this type
31 * is used only by lockd.
33 #define XDR_MAX_NETOBJ 1024
40 * Basic structure for transmission/reception of a client XDR message.
41 * Features a header (for a linear buffer containing RPC headers
42 * and the data payload for short messages), and then an array of
44 * The tail iovec allows you to append data after the page array. Its
45 * main interest is for appending padding to the pages in order to
46 * satisfy the int_32-alignment requirements in RFC1832.
48 * For the future, we might want to string several of these together
49 * in a list if anybody wants to make use of NFSv4 COMPOUND
50 * operations and/or has a need for scatter/gather involving pages.
53 struct kvec head[1], /* RPC header + non-page data */
54 tail[1]; /* Appended after page data */
57 struct page ** pages; /* Array of pages */
58 unsigned int page_base, /* Start of page data */
59 page_len, /* Length of page data */
60 flags; /* Flags for data disposition */
61 #define XDRBUF_READ 0x01 /* target of file read */
62 #define XDRBUF_WRITE 0x02 /* source of file write */
63 #define XDRBUF_SPARSE_PAGES 0x04 /* Page array is sparse */
65 unsigned int buflen, /* Total length of storage buffer */
66 len; /* Length of XDR encoded message */
70 xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
72 buf->head[0].iov_base = start;
73 buf->head[0].iov_len = len;
74 buf->tail[0].iov_len = 0;
86 #define xdr_zero cpu_to_be32(0)
87 #define xdr_one cpu_to_be32(1)
88 #define xdr_two cpu_to_be32(2)
90 #define rpc_success cpu_to_be32(RPC_SUCCESS)
91 #define rpc_prog_unavail cpu_to_be32(RPC_PROG_UNAVAIL)
92 #define rpc_prog_mismatch cpu_to_be32(RPC_PROG_MISMATCH)
93 #define rpc_proc_unavail cpu_to_be32(RPC_PROC_UNAVAIL)
94 #define rpc_garbage_args cpu_to_be32(RPC_GARBAGE_ARGS)
95 #define rpc_system_err cpu_to_be32(RPC_SYSTEM_ERR)
96 #define rpc_drop_reply cpu_to_be32(RPC_DROP_REPLY)
98 #define rpc_auth_ok cpu_to_be32(RPC_AUTH_OK)
99 #define rpc_autherr_badcred cpu_to_be32(RPC_AUTH_BADCRED)
100 #define rpc_autherr_rejectedcred cpu_to_be32(RPC_AUTH_REJECTEDCRED)
101 #define rpc_autherr_badverf cpu_to_be32(RPC_AUTH_BADVERF)
102 #define rpc_autherr_rejectedverf cpu_to_be32(RPC_AUTH_REJECTEDVERF)
103 #define rpc_autherr_tooweak cpu_to_be32(RPC_AUTH_TOOWEAK)
104 #define rpcsec_gsserr_credproblem cpu_to_be32(RPCSEC_GSS_CREDPROBLEM)
105 #define rpcsec_gsserr_ctxproblem cpu_to_be32(RPCSEC_GSS_CTXPROBLEM)
106 #define rpc_autherr_oldseqnum cpu_to_be32(101)
109 * Miscellaneous XDR helper functions
111 __be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int len);
112 __be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int len);
113 __be32 *xdr_encode_string(__be32 *p, const char *s);
114 __be32 *xdr_decode_string_inplace(__be32 *p, char **sp, unsigned int *lenp,
115 unsigned int maxlen);
116 __be32 *xdr_encode_netobj(__be32 *p, const struct xdr_netobj *);
117 __be32 *xdr_decode_netobj(__be32 *p, struct xdr_netobj *);
119 void xdr_inline_pages(struct xdr_buf *, unsigned int,
120 struct page **, unsigned int, unsigned int);
121 void xdr_terminate_string(struct xdr_buf *, const u32);
122 size_t xdr_buf_pagecount(struct xdr_buf *buf);
123 int xdr_alloc_bvec(struct xdr_buf *buf, gfp_t gfp);
124 void xdr_free_bvec(struct xdr_buf *buf);
126 static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len)
128 return xdr_encode_opaque(p, s, len);
132 * Decode 64bit quantities (NFSv3 support)
134 static inline __be32 *
135 xdr_encode_hyper(__be32 *p, __u64 val)
137 put_unaligned_be64(val, p);
141 static inline __be32 *
142 xdr_decode_hyper(__be32 *p, __u64 *valp)
144 *valp = get_unaligned_be64(p);
148 static inline __be32 *
149 xdr_decode_opaque_fixed(__be32 *p, void *ptr, unsigned int len)
152 return p + XDR_QUADLEN(len);
156 * Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
159 xdr_adjust_iovec(struct kvec *iov, __be32 *p)
161 return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base);
165 * XDR buffer helper functions
167 extern void xdr_shift_buf(struct xdr_buf *, size_t);
168 extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *);
169 extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
170 extern void xdr_buf_trim(struct xdr_buf *, unsigned int);
171 extern int xdr_buf_read_netobj(struct xdr_buf *, struct xdr_netobj *, unsigned int);
172 extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
173 extern int write_bytes_to_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
176 * Helper structure for copying from an sk_buff.
178 struct xdr_skb_reader {
185 typedef size_t (*xdr_skb_read_actor)(struct xdr_skb_reader *desc, void *to, size_t len);
187 extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *);
189 extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32);
190 extern int xdr_decode_word(struct xdr_buf *, unsigned int, u32 *);
192 struct xdr_array2_desc;
193 typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
194 struct xdr_array2_desc {
195 unsigned int elem_size;
196 unsigned int array_len;
197 unsigned int array_maxlen;
198 xdr_xcode_elem_t xcode;
201 extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
202 struct xdr_array2_desc *desc);
203 extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
204 struct xdr_array2_desc *desc);
205 extern void _copy_from_pages(char *p, struct page **pages, size_t pgbase,
209 * Provide some simple tools for XDR buffer overflow-checking etc.
212 __be32 *p; /* start of available buffer */
213 struct xdr_buf *buf; /* XDR buffer to read/write */
215 __be32 *end; /* end of available buffer space */
216 struct kvec *iov; /* pointer to the current kvec */
217 struct kvec scratch; /* Scratch buffer */
218 struct page **page_ptr; /* pointer to the current page */
219 unsigned int nwords; /* Remaining decode buffer length */
223 * These are the xdr_stream style generic XDR encode and decode functions.
225 typedef void (*kxdreproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
227 typedef int (*kxdrdproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
230 extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
231 extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
232 extern void xdr_commit_encode(struct xdr_stream *xdr);
233 extern void xdr_truncate_encode(struct xdr_stream *xdr, size_t len);
234 extern int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen);
235 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
236 unsigned int base, unsigned int len);
237 extern unsigned int xdr_stream_pos(const struct xdr_stream *xdr);
238 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
239 extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf,
240 struct page **pages, unsigned int len);
241 extern void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen);
242 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
243 extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
244 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
245 extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
248 * xdr_stream_remaining - Return the number of bytes remaining in the stream
249 * @xdr: pointer to struct xdr_stream
252 * Number of bytes remaining in @xdr before xdr->end
255 xdr_stream_remaining(const struct xdr_stream *xdr)
257 return xdr->nwords << 2;
260 ssize_t xdr_stream_decode_opaque(struct xdr_stream *xdr, void *ptr,
262 ssize_t xdr_stream_decode_opaque_dup(struct xdr_stream *xdr, void **ptr,
263 size_t maxlen, gfp_t gfp_flags);
264 ssize_t xdr_stream_decode_string(struct xdr_stream *xdr, char *str,
266 ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str,
267 size_t maxlen, gfp_t gfp_flags);
269 * xdr_align_size - Calculate padded size of an object
270 * @n: Size of an object being XDR encoded (in bytes)
273 * Size (in bytes) of the object including xdr padding
276 xdr_align_size(size_t n)
278 const size_t mask = sizeof(__u32) - 1;
280 return (n + mask) & ~mask;
284 * xdr_stream_encode_u32 - Encode a 32-bit integer
285 * @xdr: pointer to xdr_stream
286 * @n: integer to encode
289 * On success, returns length in bytes of XDR buffer consumed
290 * %-EMSGSIZE on XDR buffer overflow
292 static inline ssize_t
293 xdr_stream_encode_u32(struct xdr_stream *xdr, __u32 n)
295 const size_t len = sizeof(n);
296 __be32 *p = xdr_reserve_space(xdr, len);
305 * xdr_stream_encode_u64 - Encode a 64-bit integer
306 * @xdr: pointer to xdr_stream
307 * @n: 64-bit integer to encode
310 * On success, returns length in bytes of XDR buffer consumed
311 * %-EMSGSIZE on XDR buffer overflow
313 static inline ssize_t
314 xdr_stream_encode_u64(struct xdr_stream *xdr, __u64 n)
316 const size_t len = sizeof(n);
317 __be32 *p = xdr_reserve_space(xdr, len);
321 xdr_encode_hyper(p, n);
326 * xdr_stream_encode_opaque_inline - Encode opaque xdr data
327 * @xdr: pointer to xdr_stream
328 * @ptr: pointer to void pointer
329 * @len: size of object
332 * On success, returns length in bytes of XDR buffer consumed
333 * %-EMSGSIZE on XDR buffer overflow
335 static inline ssize_t
336 xdr_stream_encode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t len)
338 size_t count = sizeof(__u32) + xdr_align_size(len);
339 __be32 *p = xdr_reserve_space(xdr, count);
345 xdr_encode_opaque(p, NULL, len);
351 * xdr_stream_encode_opaque_fixed - Encode fixed length opaque xdr data
352 * @xdr: pointer to xdr_stream
353 * @ptr: pointer to opaque data object
354 * @len: size of object pointed to by @ptr
357 * On success, returns length in bytes of XDR buffer consumed
358 * %-EMSGSIZE on XDR buffer overflow
360 static inline ssize_t
361 xdr_stream_encode_opaque_fixed(struct xdr_stream *xdr, const void *ptr, size_t len)
363 __be32 *p = xdr_reserve_space(xdr, len);
367 xdr_encode_opaque_fixed(p, ptr, len);
368 return xdr_align_size(len);
372 * xdr_stream_encode_opaque - Encode variable length opaque xdr data
373 * @xdr: pointer to xdr_stream
374 * @ptr: pointer to opaque data object
375 * @len: size of object pointed to by @ptr
378 * On success, returns length in bytes of XDR buffer consumed
379 * %-EMSGSIZE on XDR buffer overflow
381 static inline ssize_t
382 xdr_stream_encode_opaque(struct xdr_stream *xdr, const void *ptr, size_t len)
384 size_t count = sizeof(__u32) + xdr_align_size(len);
385 __be32 *p = xdr_reserve_space(xdr, count);
389 xdr_encode_opaque(p, ptr, len);
394 * xdr_stream_encode_uint32_array - Encode variable length array of integers
395 * @xdr: pointer to xdr_stream
396 * @array: array of integers
397 * @array_size: number of elements in @array
400 * On success, returns length in bytes of XDR buffer consumed
401 * %-EMSGSIZE on XDR buffer overflow
403 static inline ssize_t
404 xdr_stream_encode_uint32_array(struct xdr_stream *xdr,
405 const __u32 *array, size_t array_size)
407 ssize_t ret = (array_size+1) * sizeof(__u32);
408 __be32 *p = xdr_reserve_space(xdr, ret);
412 *p++ = cpu_to_be32(array_size);
413 for (; array_size > 0; p++, array++, array_size--)
414 *p = cpu_to_be32p(array);
419 * xdr_stream_decode_u32 - Decode a 32-bit integer
420 * @xdr: pointer to xdr_stream
421 * @ptr: location to store integer
425 * %-EBADMSG on XDR buffer overflow
427 static inline ssize_t
428 xdr_stream_decode_u32(struct xdr_stream *xdr, __u32 *ptr)
430 const size_t count = sizeof(*ptr);
431 __be32 *p = xdr_inline_decode(xdr, count);
435 *ptr = be32_to_cpup(p);
440 * xdr_stream_decode_opaque_fixed - Decode fixed length opaque xdr data
441 * @xdr: pointer to xdr_stream
442 * @ptr: location to store data
443 * @len: size of buffer pointed to by @ptr
446 * On success, returns size of object stored in @ptr
447 * %-EBADMSG on XDR buffer overflow
449 static inline ssize_t
450 xdr_stream_decode_opaque_fixed(struct xdr_stream *xdr, void *ptr, size_t len)
452 __be32 *p = xdr_inline_decode(xdr, len);
456 xdr_decode_opaque_fixed(p, ptr, len);
461 * xdr_stream_decode_opaque_inline - Decode variable length opaque xdr data
462 * @xdr: pointer to xdr_stream
463 * @ptr: location to store pointer to opaque data
464 * @maxlen: maximum acceptable object size
466 * Note: the pointer stored in @ptr cannot be assumed valid after the XDR
467 * buffer has been destroyed, or even after calling xdr_inline_decode()
468 * on @xdr. It is therefore expected that the object it points to should
469 * be processed immediately.
472 * On success, returns size of object stored in *@ptr
473 * %-EBADMSG on XDR buffer overflow
474 * %-EMSGSIZE if the size of the object would exceed @maxlen
476 static inline ssize_t
477 xdr_stream_decode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t maxlen)
483 if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0))
486 p = xdr_inline_decode(xdr, len);
489 if (unlikely(len > maxlen))
497 * xdr_stream_decode_uint32_array - Decode variable length array of integers
498 * @xdr: pointer to xdr_stream
499 * @array: location to store the integer array or NULL
500 * @array_size: number of elements to store
503 * On success, returns number of elements stored in @array
504 * %-EBADMSG on XDR buffer overflow
505 * %-EMSGSIZE if the size of the array exceeds @array_size
507 static inline ssize_t
508 xdr_stream_decode_uint32_array(struct xdr_stream *xdr,
509 __u32 *array, size_t array_size)
515 if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0))
517 p = xdr_inline_decode(xdr, len * sizeof(*p));
522 if (len <= array_size) {
523 if (len < array_size)
524 memset(array+len, 0, (array_size-len)*sizeof(*array));
529 for (; array_size > 0; p++, array++, array_size--)
530 *array = be32_to_cpup(p);
533 #endif /* __KERNEL__ */
535 #endif /* _SUNRPC_XDR_H_ */