1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * XDR standard data types and function declarations 4 * 5 * Copyright (C) 1995-1997 Olaf Kirch <[email protected]> 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 19 struct bio_vec; 20 struct 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 38 struct 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 */ 56 struct 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 73 static inline void 74 xdr_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 *); 135 136 void xdr_inline_pages(struct xdr_buf *, unsigned int, 137 struct page **, unsigned int, unsigned int); 138 void xdr_terminate_string(const struct xdr_buf *, const u32); 139 size_t xdr_buf_pagecount(const struct xdr_buf *buf); 140 int xdr_alloc_bvec(struct xdr_buf *buf, gfp_t gfp); 141 void xdr_free_bvec(struct xdr_buf *buf); 142 143 static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len) 144 { 145 return xdr_encode_opaque(p, s, len); 146 } 147 148 /* 149 * Decode 64bit quantities (NFSv3 support) 150 */ 151 static inline __be32 * 152 xdr_encode_hyper(__be32 *p, __u64 val) 153 { 154 put_unaligned_be64(val, p); 155 return p + 2; 156 } 157 158 static inline __be32 * 159 xdr_decode_hyper(__be32 *p, __u64 *valp) 160 { 161 *valp = get_unaligned_be64(p); 162 return p + 2; 163 } 164 165 static inline __be32 * 166 xdr_decode_opaque_fixed(__be32 *p, void *ptr, unsigned int len) 167 { 168 memcpy(ptr, p, len); 169 return p + XDR_QUADLEN(len); 170 } 171 172 static inline void xdr_netobj_dup(struct xdr_netobj *dst, 173 struct xdr_netobj *src, gfp_t gfp_mask) 174 { 175 dst->data = kmemdup(src->data, src->len, gfp_mask); 176 dst->len = src->len; 177 } 178 179 /* 180 * Adjust kvec to reflect end of xdr'ed data (RPC client XDR) 181 */ 182 static inline int 183 xdr_adjust_iovec(struct kvec *iov, __be32 *p) 184 { 185 return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base); 186 } 187 188 /* 189 * XDR buffer helper functions 190 */ 191 extern void xdr_buf_from_iov(const struct kvec *, struct xdr_buf *); 192 extern int xdr_buf_subsegment(const struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int); 193 extern void xdr_buf_trim(struct xdr_buf *, unsigned int); 194 extern int read_bytes_from_xdr_buf(const struct xdr_buf *, unsigned int, void *, unsigned int); 195 extern int write_bytes_to_xdr_buf(const struct xdr_buf *, unsigned int, void *, unsigned int); 196 197 extern int xdr_encode_word(const struct xdr_buf *, unsigned int, u32); 198 extern int xdr_decode_word(const struct xdr_buf *, unsigned int, u32 *); 199 200 struct xdr_array2_desc; 201 typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem); 202 struct xdr_array2_desc { 203 unsigned int elem_size; 204 unsigned int array_len; 205 unsigned int array_maxlen; 206 xdr_xcode_elem_t xcode; 207 }; 208 209 extern int xdr_decode_array2(const struct xdr_buf *buf, unsigned int base, 210 struct xdr_array2_desc *desc); 211 extern int xdr_encode_array2(const struct xdr_buf *buf, unsigned int base, 212 struct xdr_array2_desc *desc); 213 extern void _copy_from_pages(char *p, struct page **pages, size_t pgbase, 214 size_t len); 215 216 /* 217 * Provide some simple tools for XDR buffer overflow-checking etc. 218 */ 219 struct xdr_stream { 220 __be32 *p; /* start of available buffer */ 221 struct xdr_buf *buf; /* XDR buffer to read/write */ 222 223 __be32 *end; /* end of available buffer space */ 224 struct kvec *iov; /* pointer to the current kvec */ 225 struct kvec scratch; /* Scratch buffer */ 226 struct page **page_ptr; /* pointer to the current page */ 227 unsigned int nwords; /* Remaining decode buffer length */ 228 229 struct rpc_rqst *rqst; /* For debugging */ 230 }; 231 232 /* 233 * These are the xdr_stream style generic XDR encode and decode functions. 234 */ 235 typedef void (*kxdreproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 236 const void *obj); 237 typedef int (*kxdrdproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 238 void *obj); 239 240 extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, 241 __be32 *p, struct rpc_rqst *rqst); 242 extern void xdr_init_encode_pages(struct xdr_stream *xdr, struct xdr_buf *buf, 243 struct page **pages, struct rpc_rqst *rqst); 244 extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes); 245 extern int xdr_reserve_space_vec(struct xdr_stream *xdr, struct kvec *vec, 246 size_t nbytes); 247 extern void __xdr_commit_encode(struct xdr_stream *xdr); 248 extern void xdr_truncate_encode(struct xdr_stream *xdr, size_t len); 249 extern void xdr_truncate_decode(struct xdr_stream *xdr, size_t len); 250 extern int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen); 251 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, 252 unsigned int base, unsigned int len); 253 extern unsigned int xdr_stream_pos(const struct xdr_stream *xdr); 254 extern unsigned int xdr_page_pos(const struct xdr_stream *xdr); 255 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, 256 __be32 *p, struct rpc_rqst *rqst); 257 extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf, 258 struct page **pages, unsigned int len); 259 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes); 260 extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len); 261 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len); 262 extern int xdr_process_buf(const struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data); 263 extern void xdr_set_pagelen(struct xdr_stream *, unsigned int len); 264 extern bool xdr_stream_subsegment(struct xdr_stream *xdr, struct xdr_buf *subbuf, 265 unsigned int len); 266 extern unsigned int xdr_stream_move_subsegment(struct xdr_stream *xdr, unsigned int offset, 267 unsigned int target, unsigned int length); 268 extern unsigned int xdr_stream_zero(struct xdr_stream *xdr, unsigned int offset, 269 unsigned int length); 270 271 /** 272 * xdr_set_scratch_buffer - Attach a scratch buffer for decoding data. 273 * @xdr: pointer to xdr_stream struct 274 * @buf: pointer to an empty buffer 275 * @buflen: size of 'buf' 276 * 277 * The scratch buffer is used when decoding from an array of pages. 278 * If an xdr_inline_decode() call spans across page boundaries, then 279 * we copy the data into the scratch buffer in order to allow linear 280 * access. 281 */ 282 static inline void 283 xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen) 284 { 285 xdr->scratch.iov_base = buf; 286 xdr->scratch.iov_len = buflen; 287 } 288 289 /** 290 * xdr_set_scratch_page - Attach a scratch buffer for decoding data 291 * @xdr: pointer to xdr_stream struct 292 * @page: an anonymous page 293 * 294 * See xdr_set_scratch_buffer(). 295 */ 296 static inline void 297 xdr_set_scratch_page(struct xdr_stream *xdr, struct page *page) 298 { 299 xdr_set_scratch_buffer(xdr, page_address(page), PAGE_SIZE); 300 } 301 302 /** 303 * xdr_reset_scratch_buffer - Clear scratch buffer information 304 * @xdr: pointer to xdr_stream struct 305 * 306 * See xdr_set_scratch_buffer(). 307 */ 308 static inline void 309 xdr_reset_scratch_buffer(struct xdr_stream *xdr) 310 { 311 xdr_set_scratch_buffer(xdr, NULL, 0); 312 } 313 314 /** 315 * xdr_commit_encode - Ensure all data is written to xdr->buf 316 * @xdr: pointer to xdr_stream 317 * 318 * Handle encoding across page boundaries by giving the caller a 319 * temporary location to write to, then later copying the data into 320 * place. __xdr_commit_encode() does that copying. 321 */ 322 static inline void xdr_commit_encode(struct xdr_stream *xdr) 323 { 324 if (unlikely(xdr->scratch.iov_len)) 325 __xdr_commit_encode(xdr); 326 } 327 328 /** 329 * xdr_stream_remaining - Return the number of bytes remaining in the stream 330 * @xdr: pointer to struct xdr_stream 331 * 332 * Return value: 333 * Number of bytes remaining in @xdr before xdr->end 334 */ 335 static inline size_t 336 xdr_stream_remaining(const struct xdr_stream *xdr) 337 { 338 return xdr->nwords << 2; 339 } 340 341 ssize_t xdr_stream_decode_opaque(struct xdr_stream *xdr, void *ptr, 342 size_t size); 343 ssize_t xdr_stream_decode_opaque_dup(struct xdr_stream *xdr, void **ptr, 344 size_t maxlen, gfp_t gfp_flags); 345 ssize_t xdr_stream_decode_string(struct xdr_stream *xdr, char *str, 346 size_t size); 347 ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str, 348 size_t maxlen, gfp_t gfp_flags); 349 ssize_t xdr_stream_decode_opaque_auth(struct xdr_stream *xdr, u32 *flavor, 350 void **body, unsigned int *body_len); 351 ssize_t xdr_stream_encode_opaque_auth(struct xdr_stream *xdr, u32 flavor, 352 void *body, unsigned int body_len); 353 354 /** 355 * xdr_align_size - Calculate padded size of an object 356 * @n: Size of an object being XDR encoded (in bytes) 357 * 358 * Return value: 359 * Size (in bytes) of the object including xdr padding 360 */ 361 static inline size_t 362 xdr_align_size(size_t n) 363 { 364 const size_t mask = XDR_UNIT - 1; 365 366 return (n + mask) & ~mask; 367 } 368 369 /** 370 * xdr_pad_size - Calculate size of an object's pad 371 * @n: Size of an object being XDR encoded (in bytes) 372 * 373 * This implementation avoids the need for conditional 374 * branches or modulo division. 375 * 376 * Return value: 377 * Size (in bytes) of the needed XDR pad 378 */ 379 static inline size_t xdr_pad_size(size_t n) 380 { 381 return xdr_align_size(n) - n; 382 } 383 384 /** 385 * xdr_stream_encode_item_present - Encode a "present" list item 386 * @xdr: pointer to xdr_stream 387 * 388 * Return values: 389 * On success, returns length in bytes of XDR buffer consumed 390 * %-EMSGSIZE on XDR buffer overflow 391 */ 392 static inline ssize_t xdr_stream_encode_item_present(struct xdr_stream *xdr) 393 { 394 const size_t len = XDR_UNIT; 395 __be32 *p = xdr_reserve_space(xdr, len); 396 397 if (unlikely(!p)) 398 return -EMSGSIZE; 399 *p = xdr_one; 400 return len; 401 } 402 403 /** 404 * xdr_stream_encode_item_absent - Encode a "not present" list item 405 * @xdr: pointer to xdr_stream 406 * 407 * Return values: 408 * On success, returns length in bytes of XDR buffer consumed 409 * %-EMSGSIZE on XDR buffer overflow 410 */ 411 static inline int xdr_stream_encode_item_absent(struct xdr_stream *xdr) 412 { 413 const size_t len = XDR_UNIT; 414 __be32 *p = xdr_reserve_space(xdr, len); 415 416 if (unlikely(!p)) 417 return -EMSGSIZE; 418 *p = xdr_zero; 419 return len; 420 } 421 422 /** 423 * xdr_encode_bool - Encode a boolean item 424 * @p: address in a buffer into which to encode 425 * @n: boolean value to encode 426 * 427 * Return value: 428 * Address of item following the encoded boolean 429 */ 430 static inline __be32 *xdr_encode_bool(__be32 *p, u32 n) 431 { 432 *p++ = n ? xdr_one : xdr_zero; 433 return p; 434 } 435 436 /** 437 * xdr_stream_encode_bool - Encode a boolean item 438 * @xdr: pointer to xdr_stream 439 * @n: boolean value to encode 440 * 441 * Return values: 442 * On success, returns length in bytes of XDR buffer consumed 443 * %-EMSGSIZE on XDR buffer overflow 444 */ 445 static inline int xdr_stream_encode_bool(struct xdr_stream *xdr, __u32 n) 446 { 447 const size_t len = XDR_UNIT; 448 __be32 *p = xdr_reserve_space(xdr, len); 449 450 if (unlikely(!p)) 451 return -EMSGSIZE; 452 xdr_encode_bool(p, n); 453 return len; 454 } 455 456 /** 457 * xdr_stream_encode_u32 - Encode a 32-bit integer 458 * @xdr: pointer to xdr_stream 459 * @n: integer to encode 460 * 461 * Return values: 462 * On success, returns length in bytes of XDR buffer consumed 463 * %-EMSGSIZE on XDR buffer overflow 464 */ 465 static inline ssize_t 466 xdr_stream_encode_u32(struct xdr_stream *xdr, __u32 n) 467 { 468 const size_t len = sizeof(n); 469 __be32 *p = xdr_reserve_space(xdr, len); 470 471 if (unlikely(!p)) 472 return -EMSGSIZE; 473 *p = cpu_to_be32(n); 474 return len; 475 } 476 477 /** 478 * xdr_stream_encode_be32 - Encode a big-endian 32-bit integer 479 * @xdr: pointer to xdr_stream 480 * @n: integer to encode 481 * 482 * Return values: 483 * On success, returns length in bytes of XDR buffer consumed 484 * %-EMSGSIZE on XDR buffer overflow 485 */ 486 static inline ssize_t 487 xdr_stream_encode_be32(struct xdr_stream *xdr, __be32 n) 488 { 489 const size_t len = sizeof(n); 490 __be32 *p = xdr_reserve_space(xdr, len); 491 492 if (unlikely(!p)) 493 return -EMSGSIZE; 494 *p = n; 495 return len; 496 } 497 498 /** 499 * xdr_stream_encode_u64 - Encode a 64-bit integer 500 * @xdr: pointer to xdr_stream 501 * @n: 64-bit integer to encode 502 * 503 * Return values: 504 * On success, returns length in bytes of XDR buffer consumed 505 * %-EMSGSIZE on XDR buffer overflow 506 */ 507 static inline ssize_t 508 xdr_stream_encode_u64(struct xdr_stream *xdr, __u64 n) 509 { 510 const size_t len = sizeof(n); 511 __be32 *p = xdr_reserve_space(xdr, len); 512 513 if (unlikely(!p)) 514 return -EMSGSIZE; 515 xdr_encode_hyper(p, n); 516 return len; 517 } 518 519 /** 520 * xdr_stream_encode_opaque_inline - Encode opaque xdr data 521 * @xdr: pointer to xdr_stream 522 * @ptr: pointer to void pointer 523 * @len: size of object 524 * 525 * Return values: 526 * On success, returns length in bytes of XDR buffer consumed 527 * %-EMSGSIZE on XDR buffer overflow 528 */ 529 static inline ssize_t 530 xdr_stream_encode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t len) 531 { 532 size_t count = sizeof(__u32) + xdr_align_size(len); 533 __be32 *p = xdr_reserve_space(xdr, count); 534 535 if (unlikely(!p)) { 536 *ptr = NULL; 537 return -EMSGSIZE; 538 } 539 xdr_encode_opaque(p, NULL, len); 540 *ptr = ++p; 541 return count; 542 } 543 544 /** 545 * xdr_stream_encode_opaque_fixed - Encode fixed length opaque xdr data 546 * @xdr: pointer to xdr_stream 547 * @ptr: pointer to opaque data object 548 * @len: size of object pointed to by @ptr 549 * 550 * Return values: 551 * On success, returns length in bytes of XDR buffer consumed 552 * %-EMSGSIZE on XDR buffer overflow 553 */ 554 static inline ssize_t 555 xdr_stream_encode_opaque_fixed(struct xdr_stream *xdr, const void *ptr, size_t len) 556 { 557 __be32 *p = xdr_reserve_space(xdr, len); 558 559 if (unlikely(!p)) 560 return -EMSGSIZE; 561 xdr_encode_opaque_fixed(p, ptr, len); 562 return xdr_align_size(len); 563 } 564 565 /** 566 * xdr_stream_encode_opaque - Encode variable length opaque xdr data 567 * @xdr: pointer to xdr_stream 568 * @ptr: pointer to opaque data object 569 * @len: size of object pointed to by @ptr 570 * 571 * Return values: 572 * On success, returns length in bytes of XDR buffer consumed 573 * %-EMSGSIZE on XDR buffer overflow 574 */ 575 static inline ssize_t 576 xdr_stream_encode_opaque(struct xdr_stream *xdr, const void *ptr, size_t len) 577 { 578 size_t count = sizeof(__u32) + xdr_align_size(len); 579 __be32 *p = xdr_reserve_space(xdr, count); 580 581 if (unlikely(!p)) 582 return -EMSGSIZE; 583 xdr_encode_opaque(p, ptr, len); 584 return count; 585 } 586 587 /** 588 * xdr_stream_encode_uint32_array - Encode variable length array of integers 589 * @xdr: pointer to xdr_stream 590 * @array: array of integers 591 * @array_size: number of elements in @array 592 * 593 * Return values: 594 * On success, returns length in bytes of XDR buffer consumed 595 * %-EMSGSIZE on XDR buffer overflow 596 */ 597 static inline ssize_t 598 xdr_stream_encode_uint32_array(struct xdr_stream *xdr, 599 const __u32 *array, size_t array_size) 600 { 601 ssize_t ret = (array_size+1) * sizeof(__u32); 602 __be32 *p = xdr_reserve_space(xdr, ret); 603 604 if (unlikely(!p)) 605 return -EMSGSIZE; 606 *p++ = cpu_to_be32(array_size); 607 for (; array_size > 0; p++, array++, array_size--) 608 *p = cpu_to_be32p(array); 609 return ret; 610 } 611 612 /** 613 * xdr_item_is_absent - symbolically handle XDR discriminators 614 * @p: pointer to undecoded discriminator 615 * 616 * Return values: 617 * %true if the following XDR item is absent 618 * %false if the following XDR item is present 619 */ 620 static inline bool xdr_item_is_absent(const __be32 *p) 621 { 622 return *p == xdr_zero; 623 } 624 625 /** 626 * xdr_item_is_present - symbolically handle XDR discriminators 627 * @p: pointer to undecoded discriminator 628 * 629 * Return values: 630 * %true if the following XDR item is present 631 * %false if the following XDR item is absent 632 */ 633 static inline bool xdr_item_is_present(const __be32 *p) 634 { 635 return *p != xdr_zero; 636 } 637 638 /** 639 * xdr_stream_decode_bool - Decode a boolean 640 * @xdr: pointer to xdr_stream 641 * @ptr: pointer to a u32 in which to store the result 642 * 643 * Return values: 644 * %0 on success 645 * %-EBADMSG on XDR buffer overflow 646 */ 647 static inline ssize_t 648 xdr_stream_decode_bool(struct xdr_stream *xdr, __u32 *ptr) 649 { 650 const size_t count = sizeof(*ptr); 651 __be32 *p = xdr_inline_decode(xdr, count); 652 653 if (unlikely(!p)) 654 return -EBADMSG; 655 *ptr = (*p != xdr_zero); 656 return 0; 657 } 658 659 /** 660 * xdr_stream_decode_u32 - Decode a 32-bit integer 661 * @xdr: pointer to xdr_stream 662 * @ptr: location to store integer 663 * 664 * Return values: 665 * %0 on success 666 * %-EBADMSG on XDR buffer overflow 667 */ 668 static inline ssize_t 669 xdr_stream_decode_u32(struct xdr_stream *xdr, __u32 *ptr) 670 { 671 const size_t count = sizeof(*ptr); 672 __be32 *p = xdr_inline_decode(xdr, count); 673 674 if (unlikely(!p)) 675 return -EBADMSG; 676 *ptr = be32_to_cpup(p); 677 return 0; 678 } 679 680 /** 681 * xdr_stream_decode_u64 - Decode a 64-bit integer 682 * @xdr: pointer to xdr_stream 683 * @ptr: location to store 64-bit integer 684 * 685 * Return values: 686 * %0 on success 687 * %-EBADMSG on XDR buffer overflow 688 */ 689 static inline ssize_t 690 xdr_stream_decode_u64(struct xdr_stream *xdr, __u64 *ptr) 691 { 692 const size_t count = sizeof(*ptr); 693 __be32 *p = xdr_inline_decode(xdr, count); 694 695 if (unlikely(!p)) 696 return -EBADMSG; 697 xdr_decode_hyper(p, ptr); 698 return 0; 699 } 700 701 /** 702 * xdr_stream_decode_opaque_fixed - Decode fixed length opaque xdr data 703 * @xdr: pointer to xdr_stream 704 * @ptr: location to store data 705 * @len: size of buffer pointed to by @ptr 706 * 707 * Return values: 708 * On success, returns size of object stored in @ptr 709 * %-EBADMSG on XDR buffer overflow 710 */ 711 static inline ssize_t 712 xdr_stream_decode_opaque_fixed(struct xdr_stream *xdr, void *ptr, size_t len) 713 { 714 __be32 *p = xdr_inline_decode(xdr, len); 715 716 if (unlikely(!p)) 717 return -EBADMSG; 718 xdr_decode_opaque_fixed(p, ptr, len); 719 return len; 720 } 721 722 /** 723 * xdr_stream_decode_opaque_inline - Decode variable length opaque xdr data 724 * @xdr: pointer to xdr_stream 725 * @ptr: location to store pointer to opaque data 726 * @maxlen: maximum acceptable object size 727 * 728 * Note: the pointer stored in @ptr cannot be assumed valid after the XDR 729 * buffer has been destroyed, or even after calling xdr_inline_decode() 730 * on @xdr. It is therefore expected that the object it points to should 731 * be processed immediately. 732 * 733 * Return values: 734 * On success, returns size of object stored in *@ptr 735 * %-EBADMSG on XDR buffer overflow 736 * %-EMSGSIZE if the size of the object would exceed @maxlen 737 */ 738 static inline ssize_t 739 xdr_stream_decode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t maxlen) 740 { 741 __be32 *p; 742 __u32 len; 743 744 *ptr = NULL; 745 if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0)) 746 return -EBADMSG; 747 if (len != 0) { 748 p = xdr_inline_decode(xdr, len); 749 if (unlikely(!p)) 750 return -EBADMSG; 751 if (unlikely(len > maxlen)) 752 return -EMSGSIZE; 753 *ptr = p; 754 } 755 return len; 756 } 757 758 /** 759 * xdr_stream_decode_uint32_array - Decode variable length array of integers 760 * @xdr: pointer to xdr_stream 761 * @array: location to store the integer array or NULL 762 * @array_size: number of elements to store 763 * 764 * Return values: 765 * On success, returns number of elements stored in @array 766 * %-EBADMSG on XDR buffer overflow 767 * %-EMSGSIZE if the size of the array exceeds @array_size 768 */ 769 static inline ssize_t 770 xdr_stream_decode_uint32_array(struct xdr_stream *xdr, 771 __u32 *array, size_t array_size) 772 { 773 __be32 *p; 774 __u32 len; 775 ssize_t retval; 776 777 if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0)) 778 return -EBADMSG; 779 if (len > SIZE_MAX / sizeof(*p)) 780 return -EBADMSG; 781 p = xdr_inline_decode(xdr, len * sizeof(*p)); 782 if (unlikely(!p)) 783 return -EBADMSG; 784 if (array == NULL) 785 return len; 786 if (len <= array_size) { 787 if (len < array_size) 788 memset(array+len, 0, (array_size-len)*sizeof(*array)); 789 array_size = len; 790 retval = len; 791 } else 792 retval = -EMSGSIZE; 793 for (; array_size > 0; p++, array++, array_size--) 794 *array = be32_to_cpup(p); 795 return retval; 796 } 797 798 #endif /* _SUNRPC_XDR_H_ */ 799