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, size_t nbytes); 246 extern void __xdr_commit_encode(struct xdr_stream *xdr); 247 extern void xdr_truncate_encode(struct xdr_stream *xdr, size_t len); 248 extern void xdr_truncate_decode(struct xdr_stream *xdr, size_t len); 249 extern int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen); 250 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, 251 unsigned int base, unsigned int len); 252 extern unsigned int xdr_stream_pos(const struct xdr_stream *xdr); 253 extern unsigned int xdr_page_pos(const struct xdr_stream *xdr); 254 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, 255 __be32 *p, struct rpc_rqst *rqst); 256 extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf, 257 struct page **pages, unsigned int len); 258 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes); 259 extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len); 260 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len); 261 extern int xdr_process_buf(const struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data); 262 extern void xdr_set_pagelen(struct xdr_stream *, unsigned int len); 263 extern bool xdr_stream_subsegment(struct xdr_stream *xdr, struct xdr_buf *subbuf, 264 unsigned int len); 265 extern unsigned int xdr_stream_move_subsegment(struct xdr_stream *xdr, unsigned int offset, 266 unsigned int target, unsigned int length); 267 extern unsigned int xdr_stream_zero(struct xdr_stream *xdr, unsigned int offset, 268 unsigned int length); 269 270 /** 271 * xdr_set_scratch_buffer - Attach a scratch buffer for decoding data. 272 * @xdr: pointer to xdr_stream struct 273 * @buf: pointer to an empty buffer 274 * @buflen: size of 'buf' 275 * 276 * The scratch buffer is used when decoding from an array of pages. 277 * If an xdr_inline_decode() call spans across page boundaries, then 278 * we copy the data into the scratch buffer in order to allow linear 279 * access. 280 */ 281 static inline void 282 xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen) 283 { 284 xdr->scratch.iov_base = buf; 285 xdr->scratch.iov_len = buflen; 286 } 287 288 /** 289 * xdr_set_scratch_page - Attach a scratch buffer for decoding data 290 * @xdr: pointer to xdr_stream struct 291 * @page: an anonymous page 292 * 293 * See xdr_set_scratch_buffer(). 294 */ 295 static inline void 296 xdr_set_scratch_page(struct xdr_stream *xdr, struct page *page) 297 { 298 xdr_set_scratch_buffer(xdr, page_address(page), PAGE_SIZE); 299 } 300 301 /** 302 * xdr_reset_scratch_buffer - Clear scratch buffer information 303 * @xdr: pointer to xdr_stream struct 304 * 305 * See xdr_set_scratch_buffer(). 306 */ 307 static inline void 308 xdr_reset_scratch_buffer(struct xdr_stream *xdr) 309 { 310 xdr_set_scratch_buffer(xdr, NULL, 0); 311 } 312 313 /** 314 * xdr_commit_encode - Ensure all data is written to xdr->buf 315 * @xdr: pointer to xdr_stream 316 * 317 * Handle encoding across page boundaries by giving the caller a 318 * temporary location to write to, then later copying the data into 319 * place. __xdr_commit_encode() does that copying. 320 */ 321 static inline void xdr_commit_encode(struct xdr_stream *xdr) 322 { 323 if (unlikely(xdr->scratch.iov_len)) 324 __xdr_commit_encode(xdr); 325 } 326 327 /** 328 * xdr_stream_remaining - Return the number of bytes remaining in the stream 329 * @xdr: pointer to struct xdr_stream 330 * 331 * Return value: 332 * Number of bytes remaining in @xdr before xdr->end 333 */ 334 static inline size_t 335 xdr_stream_remaining(const struct xdr_stream *xdr) 336 { 337 return xdr->nwords << 2; 338 } 339 340 ssize_t xdr_stream_decode_opaque(struct xdr_stream *xdr, void *ptr, 341 size_t size); 342 ssize_t xdr_stream_decode_opaque_dup(struct xdr_stream *xdr, void **ptr, 343 size_t maxlen, gfp_t gfp_flags); 344 ssize_t xdr_stream_decode_string(struct xdr_stream *xdr, char *str, 345 size_t size); 346 ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str, 347 size_t maxlen, gfp_t gfp_flags); 348 ssize_t xdr_stream_decode_opaque_auth(struct xdr_stream *xdr, u32 *flavor, 349 void **body, unsigned int *body_len); 350 ssize_t xdr_stream_encode_opaque_auth(struct xdr_stream *xdr, u32 flavor, 351 void *body, unsigned int body_len); 352 353 /** 354 * xdr_align_size - Calculate padded size of an object 355 * @n: Size of an object being XDR encoded (in bytes) 356 * 357 * Return value: 358 * Size (in bytes) of the object including xdr padding 359 */ 360 static inline size_t 361 xdr_align_size(size_t n) 362 { 363 const size_t mask = XDR_UNIT - 1; 364 365 return (n + mask) & ~mask; 366 } 367 368 /** 369 * xdr_pad_size - Calculate size of an object's pad 370 * @n: Size of an object being XDR encoded (in bytes) 371 * 372 * This implementation avoids the need for conditional 373 * branches or modulo division. 374 * 375 * Return value: 376 * Size (in bytes) of the needed XDR pad 377 */ 378 static inline size_t xdr_pad_size(size_t n) 379 { 380 return xdr_align_size(n) - n; 381 } 382 383 /** 384 * xdr_stream_encode_item_present - Encode a "present" list item 385 * @xdr: pointer to xdr_stream 386 * 387 * Return values: 388 * On success, returns length in bytes of XDR buffer consumed 389 * %-EMSGSIZE on XDR buffer overflow 390 */ 391 static inline ssize_t xdr_stream_encode_item_present(struct xdr_stream *xdr) 392 { 393 const size_t len = XDR_UNIT; 394 __be32 *p = xdr_reserve_space(xdr, len); 395 396 if (unlikely(!p)) 397 return -EMSGSIZE; 398 *p = xdr_one; 399 return len; 400 } 401 402 /** 403 * xdr_stream_encode_item_absent - Encode a "not present" list item 404 * @xdr: pointer to xdr_stream 405 * 406 * Return values: 407 * On success, returns length in bytes of XDR buffer consumed 408 * %-EMSGSIZE on XDR buffer overflow 409 */ 410 static inline int xdr_stream_encode_item_absent(struct xdr_stream *xdr) 411 { 412 const size_t len = XDR_UNIT; 413 __be32 *p = xdr_reserve_space(xdr, len); 414 415 if (unlikely(!p)) 416 return -EMSGSIZE; 417 *p = xdr_zero; 418 return len; 419 } 420 421 /** 422 * xdr_encode_bool - Encode a boolean item 423 * @p: address in a buffer into which to encode 424 * @n: boolean value to encode 425 * 426 * Return value: 427 * Address of item following the encoded boolean 428 */ 429 static inline __be32 *xdr_encode_bool(__be32 *p, u32 n) 430 { 431 *p++ = n ? xdr_one : xdr_zero; 432 return p; 433 } 434 435 /** 436 * xdr_stream_encode_bool - Encode a boolean item 437 * @xdr: pointer to xdr_stream 438 * @n: boolean value to encode 439 * 440 * Return values: 441 * On success, returns length in bytes of XDR buffer consumed 442 * %-EMSGSIZE on XDR buffer overflow 443 */ 444 static inline int xdr_stream_encode_bool(struct xdr_stream *xdr, __u32 n) 445 { 446 const size_t len = XDR_UNIT; 447 __be32 *p = xdr_reserve_space(xdr, len); 448 449 if (unlikely(!p)) 450 return -EMSGSIZE; 451 xdr_encode_bool(p, n); 452 return len; 453 } 454 455 /** 456 * xdr_stream_encode_u32 - Encode a 32-bit integer 457 * @xdr: pointer to xdr_stream 458 * @n: integer to encode 459 * 460 * Return values: 461 * On success, returns length in bytes of XDR buffer consumed 462 * %-EMSGSIZE on XDR buffer overflow 463 */ 464 static inline ssize_t 465 xdr_stream_encode_u32(struct xdr_stream *xdr, __u32 n) 466 { 467 const size_t len = sizeof(n); 468 __be32 *p = xdr_reserve_space(xdr, len); 469 470 if (unlikely(!p)) 471 return -EMSGSIZE; 472 *p = cpu_to_be32(n); 473 return len; 474 } 475 476 /** 477 * xdr_stream_encode_be32 - Encode a big-endian 32-bit integer 478 * @xdr: pointer to xdr_stream 479 * @n: integer to encode 480 * 481 * Return values: 482 * On success, returns length in bytes of XDR buffer consumed 483 * %-EMSGSIZE on XDR buffer overflow 484 */ 485 static inline ssize_t 486 xdr_stream_encode_be32(struct xdr_stream *xdr, __be32 n) 487 { 488 const size_t len = sizeof(n); 489 __be32 *p = xdr_reserve_space(xdr, len); 490 491 if (unlikely(!p)) 492 return -EMSGSIZE; 493 *p = n; 494 return len; 495 } 496 497 /** 498 * xdr_stream_encode_u64 - Encode a 64-bit integer 499 * @xdr: pointer to xdr_stream 500 * @n: 64-bit integer to encode 501 * 502 * Return values: 503 * On success, returns length in bytes of XDR buffer consumed 504 * %-EMSGSIZE on XDR buffer overflow 505 */ 506 static inline ssize_t 507 xdr_stream_encode_u64(struct xdr_stream *xdr, __u64 n) 508 { 509 const size_t len = sizeof(n); 510 __be32 *p = xdr_reserve_space(xdr, len); 511 512 if (unlikely(!p)) 513 return -EMSGSIZE; 514 xdr_encode_hyper(p, n); 515 return len; 516 } 517 518 /** 519 * xdr_stream_encode_opaque_inline - Encode opaque xdr data 520 * @xdr: pointer to xdr_stream 521 * @ptr: pointer to void pointer 522 * @len: size of object 523 * 524 * Return values: 525 * On success, returns length in bytes of XDR buffer consumed 526 * %-EMSGSIZE on XDR buffer overflow 527 */ 528 static inline ssize_t 529 xdr_stream_encode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t len) 530 { 531 size_t count = sizeof(__u32) + xdr_align_size(len); 532 __be32 *p = xdr_reserve_space(xdr, count); 533 534 if (unlikely(!p)) { 535 *ptr = NULL; 536 return -EMSGSIZE; 537 } 538 xdr_encode_opaque(p, NULL, len); 539 *ptr = ++p; 540 return count; 541 } 542 543 /** 544 * xdr_stream_encode_opaque_fixed - Encode fixed length opaque xdr data 545 * @xdr: pointer to xdr_stream 546 * @ptr: pointer to opaque data object 547 * @len: size of object pointed to by @ptr 548 * 549 * Return values: 550 * On success, returns length in bytes of XDR buffer consumed 551 * %-EMSGSIZE on XDR buffer overflow 552 */ 553 static inline ssize_t 554 xdr_stream_encode_opaque_fixed(struct xdr_stream *xdr, const void *ptr, size_t len) 555 { 556 __be32 *p = xdr_reserve_space(xdr, len); 557 558 if (unlikely(!p)) 559 return -EMSGSIZE; 560 xdr_encode_opaque_fixed(p, ptr, len); 561 return xdr_align_size(len); 562 } 563 564 /** 565 * xdr_stream_encode_opaque - Encode variable length opaque xdr data 566 * @xdr: pointer to xdr_stream 567 * @ptr: pointer to opaque data object 568 * @len: size of object pointed to by @ptr 569 * 570 * Return values: 571 * On success, returns length in bytes of XDR buffer consumed 572 * %-EMSGSIZE on XDR buffer overflow 573 */ 574 static inline ssize_t 575 xdr_stream_encode_opaque(struct xdr_stream *xdr, const void *ptr, size_t len) 576 { 577 size_t count = sizeof(__u32) + xdr_align_size(len); 578 __be32 *p = xdr_reserve_space(xdr, count); 579 580 if (unlikely(!p)) 581 return -EMSGSIZE; 582 xdr_encode_opaque(p, ptr, len); 583 return count; 584 } 585 586 /** 587 * xdr_stream_encode_uint32_array - Encode variable length array of integers 588 * @xdr: pointer to xdr_stream 589 * @array: array of integers 590 * @array_size: number of elements in @array 591 * 592 * Return values: 593 * On success, returns length in bytes of XDR buffer consumed 594 * %-EMSGSIZE on XDR buffer overflow 595 */ 596 static inline ssize_t 597 xdr_stream_encode_uint32_array(struct xdr_stream *xdr, 598 const __u32 *array, size_t array_size) 599 { 600 ssize_t ret = (array_size+1) * sizeof(__u32); 601 __be32 *p = xdr_reserve_space(xdr, ret); 602 603 if (unlikely(!p)) 604 return -EMSGSIZE; 605 *p++ = cpu_to_be32(array_size); 606 for (; array_size > 0; p++, array++, array_size--) 607 *p = cpu_to_be32p(array); 608 return ret; 609 } 610 611 /** 612 * xdr_item_is_absent - symbolically handle XDR discriminators 613 * @p: pointer to undecoded discriminator 614 * 615 * Return values: 616 * %true if the following XDR item is absent 617 * %false if the following XDR item is present 618 */ 619 static inline bool xdr_item_is_absent(const __be32 *p) 620 { 621 return *p == xdr_zero; 622 } 623 624 /** 625 * xdr_item_is_present - symbolically handle XDR discriminators 626 * @p: pointer to undecoded discriminator 627 * 628 * Return values: 629 * %true if the following XDR item is present 630 * %false if the following XDR item is absent 631 */ 632 static inline bool xdr_item_is_present(const __be32 *p) 633 { 634 return *p != xdr_zero; 635 } 636 637 /** 638 * xdr_stream_decode_bool - Decode a boolean 639 * @xdr: pointer to xdr_stream 640 * @ptr: pointer to a u32 in which to store the result 641 * 642 * Return values: 643 * %0 on success 644 * %-EBADMSG on XDR buffer overflow 645 */ 646 static inline ssize_t 647 xdr_stream_decode_bool(struct xdr_stream *xdr, __u32 *ptr) 648 { 649 const size_t count = sizeof(*ptr); 650 __be32 *p = xdr_inline_decode(xdr, count); 651 652 if (unlikely(!p)) 653 return -EBADMSG; 654 *ptr = (*p != xdr_zero); 655 return 0; 656 } 657 658 /** 659 * xdr_stream_decode_u32 - Decode a 32-bit integer 660 * @xdr: pointer to xdr_stream 661 * @ptr: location to store integer 662 * 663 * Return values: 664 * %0 on success 665 * %-EBADMSG on XDR buffer overflow 666 */ 667 static inline ssize_t 668 xdr_stream_decode_u32(struct xdr_stream *xdr, __u32 *ptr) 669 { 670 const size_t count = sizeof(*ptr); 671 __be32 *p = xdr_inline_decode(xdr, count); 672 673 if (unlikely(!p)) 674 return -EBADMSG; 675 *ptr = be32_to_cpup(p); 676 return 0; 677 } 678 679 /** 680 * xdr_stream_decode_u64 - Decode a 64-bit integer 681 * @xdr: pointer to xdr_stream 682 * @ptr: location to store 64-bit integer 683 * 684 * Return values: 685 * %0 on success 686 * %-EBADMSG on XDR buffer overflow 687 */ 688 static inline ssize_t 689 xdr_stream_decode_u64(struct xdr_stream *xdr, __u64 *ptr) 690 { 691 const size_t count = sizeof(*ptr); 692 __be32 *p = xdr_inline_decode(xdr, count); 693 694 if (unlikely(!p)) 695 return -EBADMSG; 696 xdr_decode_hyper(p, ptr); 697 return 0; 698 } 699 700 /** 701 * xdr_stream_decode_opaque_fixed - Decode fixed length opaque xdr data 702 * @xdr: pointer to xdr_stream 703 * @ptr: location to store data 704 * @len: size of buffer pointed to by @ptr 705 * 706 * Return values: 707 * On success, returns size of object stored in @ptr 708 * %-EBADMSG on XDR buffer overflow 709 */ 710 static inline ssize_t 711 xdr_stream_decode_opaque_fixed(struct xdr_stream *xdr, void *ptr, size_t len) 712 { 713 __be32 *p = xdr_inline_decode(xdr, len); 714 715 if (unlikely(!p)) 716 return -EBADMSG; 717 xdr_decode_opaque_fixed(p, ptr, len); 718 return len; 719 } 720 721 /** 722 * xdr_stream_decode_opaque_inline - Decode variable length opaque xdr data 723 * @xdr: pointer to xdr_stream 724 * @ptr: location to store pointer to opaque data 725 * @maxlen: maximum acceptable object size 726 * 727 * Note: the pointer stored in @ptr cannot be assumed valid after the XDR 728 * buffer has been destroyed, or even after calling xdr_inline_decode() 729 * on @xdr. It is therefore expected that the object it points to should 730 * be processed immediately. 731 * 732 * Return values: 733 * On success, returns size of object stored in *@ptr 734 * %-EBADMSG on XDR buffer overflow 735 * %-EMSGSIZE if the size of the object would exceed @maxlen 736 */ 737 static inline ssize_t 738 xdr_stream_decode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t maxlen) 739 { 740 __be32 *p; 741 __u32 len; 742 743 *ptr = NULL; 744 if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0)) 745 return -EBADMSG; 746 if (len != 0) { 747 p = xdr_inline_decode(xdr, len); 748 if (unlikely(!p)) 749 return -EBADMSG; 750 if (unlikely(len > maxlen)) 751 return -EMSGSIZE; 752 *ptr = p; 753 } 754 return len; 755 } 756 757 /** 758 * xdr_stream_decode_uint32_array - Decode variable length array of integers 759 * @xdr: pointer to xdr_stream 760 * @array: location to store the integer array or NULL 761 * @array_size: number of elements to store 762 * 763 * Return values: 764 * On success, returns number of elements stored in @array 765 * %-EBADMSG on XDR buffer overflow 766 * %-EMSGSIZE if the size of the array exceeds @array_size 767 */ 768 static inline ssize_t 769 xdr_stream_decode_uint32_array(struct xdr_stream *xdr, 770 __u32 *array, size_t array_size) 771 { 772 __be32 *p; 773 __u32 len; 774 ssize_t retval; 775 776 if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0)) 777 return -EBADMSG; 778 if (len > SIZE_MAX / sizeof(*p)) 779 return -EBADMSG; 780 p = xdr_inline_decode(xdr, len * sizeof(*p)); 781 if (unlikely(!p)) 782 return -EBADMSG; 783 if (array == NULL) 784 return len; 785 if (len <= array_size) { 786 if (len < array_size) 787 memset(array+len, 0, (array_size-len)*sizeof(*array)); 788 array_size = len; 789 retval = len; 790 } else 791 retval = -EMSGSIZE; 792 for (; array_size > 0; p++, array++, array_size--) 793 *array = be32_to_cpup(p); 794 return retval; 795 } 796 797 #endif /* _SUNRPC_XDR_H_ */ 798