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 * Buffer adjustment 24 */ 25 #define XDR_QUADLEN(l) (((l) + 3) >> 2) 26 27 /* 28 * Generic opaque `network object.' At the kernel level, this type 29 * is used only by lockd. 30 */ 31 #define XDR_MAX_NETOBJ 1024 32 struct xdr_netobj { 33 unsigned int len; 34 u8 * data; 35 }; 36 37 /* 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 41 * pages. 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. 45 * 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. 49 */ 50 struct xdr_buf { 51 struct kvec head[1], /* RPC header + non-page data */ 52 tail[1]; /* Appended after page data */ 53 54 struct bio_vec *bvec; 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 */ 62 63 unsigned int buflen, /* Total length of storage buffer */ 64 len; /* Length of XDR encoded message */ 65 }; 66 67 static inline void 68 xdr_buf_init(struct xdr_buf *buf, void *start, size_t len) 69 { 70 buf->head[0].iov_base = start; 71 buf->head[0].iov_len = len; 72 buf->tail[0].iov_len = 0; 73 buf->pages = NULL; 74 buf->page_len = 0; 75 buf->flags = 0; 76 buf->len = 0; 77 buf->buflen = len; 78 } 79 80 /* 81 * pre-xdr'ed macros. 82 */ 83 84 #define xdr_zero cpu_to_be32(0) 85 #define xdr_one cpu_to_be32(1) 86 #define xdr_two cpu_to_be32(2) 87 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) 92 93 #define rpc_call cpu_to_be32(RPC_CALL) 94 #define rpc_reply cpu_to_be32(RPC_REPLY) 95 96 #define rpc_msg_accepted cpu_to_be32(RPC_MSG_ACCEPTED) 97 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) 105 106 #define rpc_mismatch cpu_to_be32(RPC_MISMATCH) 107 #define rpc_auth_error cpu_to_be32(RPC_AUTH_ERROR) 108 109 #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) 117 118 /* 119 * Miscellaneous XDR helper functions 120 */ 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 *); 128 129 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); 135 136 static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len) 137 { 138 return xdr_encode_opaque(p, s, len); 139 } 140 141 /* 142 * Decode 64bit quantities (NFSv3 support) 143 */ 144 static inline __be32 * 145 xdr_encode_hyper(__be32 *p, __u64 val) 146 { 147 put_unaligned_be64(val, p); 148 return p + 2; 149 } 150 151 static inline __be32 * 152 xdr_decode_hyper(__be32 *p, __u64 *valp) 153 { 154 *valp = get_unaligned_be64(p); 155 return p + 2; 156 } 157 158 static inline __be32 * 159 xdr_decode_opaque_fixed(__be32 *p, void *ptr, unsigned int len) 160 { 161 memcpy(ptr, p, len); 162 return p + XDR_QUADLEN(len); 163 } 164 165 static inline void xdr_netobj_dup(struct xdr_netobj *dst, 166 struct xdr_netobj *src, gfp_t gfp_mask) 167 { 168 dst->data = kmemdup(src->data, src->len, gfp_mask); 169 dst->len = src->len; 170 } 171 172 /* 173 * Adjust kvec to reflect end of xdr'ed data (RPC client XDR) 174 */ 175 static inline int 176 xdr_adjust_iovec(struct kvec *iov, __be32 *p) 177 { 178 return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base); 179 } 180 181 /* 182 * XDR buffer helper functions 183 */ 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 int xdr_buf_read_mic(struct xdr_buf *, struct xdr_netobj *, 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); 190 191 /* 192 * Helper structure for copying from an sk_buff. 193 */ 194 struct xdr_skb_reader { 195 struct sk_buff *skb; 196 unsigned int offset; 197 size_t count; 198 __wsum csum; 199 }; 200 201 typedef size_t (*xdr_skb_read_actor)(struct xdr_skb_reader *desc, void *to, size_t len); 202 203 extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *); 204 205 extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32); 206 extern int xdr_decode_word(struct xdr_buf *, unsigned int, u32 *); 207 208 struct xdr_array2_desc; 209 typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem); 210 struct xdr_array2_desc { 211 unsigned int elem_size; 212 unsigned int array_len; 213 unsigned int array_maxlen; 214 xdr_xcode_elem_t xcode; 215 }; 216 217 extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base, 218 struct xdr_array2_desc *desc); 219 extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base, 220 struct xdr_array2_desc *desc); 221 extern void _copy_from_pages(char *p, struct page **pages, size_t pgbase, 222 size_t len); 223 224 /* 225 * Provide some simple tools for XDR buffer overflow-checking etc. 226 */ 227 struct xdr_stream { 228 __be32 *p; /* start of available buffer */ 229 struct xdr_buf *buf; /* XDR buffer to read/write */ 230 231 __be32 *end; /* end of available buffer space */ 232 struct kvec *iov; /* pointer to the current kvec */ 233 struct kvec scratch; /* Scratch buffer */ 234 struct page **page_ptr; /* pointer to the current page */ 235 unsigned int nwords; /* Remaining decode buffer length */ 236 237 struct rpc_rqst *rqst; /* For debugging */ 238 }; 239 240 /* 241 * These are the xdr_stream style generic XDR encode and decode functions. 242 */ 243 typedef void (*kxdreproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 244 const void *obj); 245 typedef int (*kxdrdproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 246 void *obj); 247 248 extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, 249 __be32 *p, struct rpc_rqst *rqst); 250 extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes); 251 extern void xdr_commit_encode(struct xdr_stream *xdr); 252 extern void xdr_truncate_encode(struct xdr_stream *xdr, size_t len); 253 extern int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen); 254 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, 255 unsigned int base, unsigned int len); 256 extern unsigned int xdr_stream_pos(const struct xdr_stream *xdr); 257 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, 258 __be32 *p, struct rpc_rqst *rqst); 259 extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf, 260 struct page **pages, unsigned int len); 261 extern void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen); 262 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes); 263 extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len); 264 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len); 265 extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data); 266 267 /** 268 * xdr_stream_remaining - Return the number of bytes remaining in the stream 269 * @xdr: pointer to struct xdr_stream 270 * 271 * Return value: 272 * Number of bytes remaining in @xdr before xdr->end 273 */ 274 static inline size_t 275 xdr_stream_remaining(const struct xdr_stream *xdr) 276 { 277 return xdr->nwords << 2; 278 } 279 280 ssize_t xdr_stream_decode_opaque(struct xdr_stream *xdr, void *ptr, 281 size_t size); 282 ssize_t xdr_stream_decode_opaque_dup(struct xdr_stream *xdr, void **ptr, 283 size_t maxlen, gfp_t gfp_flags); 284 ssize_t xdr_stream_decode_string(struct xdr_stream *xdr, char *str, 285 size_t size); 286 ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str, 287 size_t maxlen, gfp_t gfp_flags); 288 /** 289 * xdr_align_size - Calculate padded size of an object 290 * @n: Size of an object being XDR encoded (in bytes) 291 * 292 * Return value: 293 * Size (in bytes) of the object including xdr padding 294 */ 295 static inline size_t 296 xdr_align_size(size_t n) 297 { 298 const size_t mask = sizeof(__u32) - 1; 299 300 return (n + mask) & ~mask; 301 } 302 303 /** 304 * xdr_stream_encode_u32 - Encode a 32-bit integer 305 * @xdr: pointer to xdr_stream 306 * @n: integer to encode 307 * 308 * Return values: 309 * On success, returns length in bytes of XDR buffer consumed 310 * %-EMSGSIZE on XDR buffer overflow 311 */ 312 static inline ssize_t 313 xdr_stream_encode_u32(struct xdr_stream *xdr, __u32 n) 314 { 315 const size_t len = sizeof(n); 316 __be32 *p = xdr_reserve_space(xdr, len); 317 318 if (unlikely(!p)) 319 return -EMSGSIZE; 320 *p = cpu_to_be32(n); 321 return len; 322 } 323 324 /** 325 * xdr_stream_encode_u64 - Encode a 64-bit integer 326 * @xdr: pointer to xdr_stream 327 * @n: 64-bit integer to encode 328 * 329 * Return values: 330 * On success, returns length in bytes of XDR buffer consumed 331 * %-EMSGSIZE on XDR buffer overflow 332 */ 333 static inline ssize_t 334 xdr_stream_encode_u64(struct xdr_stream *xdr, __u64 n) 335 { 336 const size_t len = sizeof(n); 337 __be32 *p = xdr_reserve_space(xdr, len); 338 339 if (unlikely(!p)) 340 return -EMSGSIZE; 341 xdr_encode_hyper(p, n); 342 return len; 343 } 344 345 /** 346 * xdr_stream_encode_opaque_inline - Encode opaque xdr data 347 * @xdr: pointer to xdr_stream 348 * @ptr: pointer to void pointer 349 * @len: size of object 350 * 351 * Return values: 352 * On success, returns length in bytes of XDR buffer consumed 353 * %-EMSGSIZE on XDR buffer overflow 354 */ 355 static inline ssize_t 356 xdr_stream_encode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t len) 357 { 358 size_t count = sizeof(__u32) + xdr_align_size(len); 359 __be32 *p = xdr_reserve_space(xdr, count); 360 361 if (unlikely(!p)) { 362 *ptr = NULL; 363 return -EMSGSIZE; 364 } 365 xdr_encode_opaque(p, NULL, len); 366 *ptr = ++p; 367 return count; 368 } 369 370 /** 371 * xdr_stream_encode_opaque_fixed - Encode fixed length opaque xdr data 372 * @xdr: pointer to xdr_stream 373 * @ptr: pointer to opaque data object 374 * @len: size of object pointed to by @ptr 375 * 376 * Return values: 377 * On success, returns length in bytes of XDR buffer consumed 378 * %-EMSGSIZE on XDR buffer overflow 379 */ 380 static inline ssize_t 381 xdr_stream_encode_opaque_fixed(struct xdr_stream *xdr, const void *ptr, size_t len) 382 { 383 __be32 *p = xdr_reserve_space(xdr, len); 384 385 if (unlikely(!p)) 386 return -EMSGSIZE; 387 xdr_encode_opaque_fixed(p, ptr, len); 388 return xdr_align_size(len); 389 } 390 391 /** 392 * xdr_stream_encode_opaque - Encode variable length opaque xdr data 393 * @xdr: pointer to xdr_stream 394 * @ptr: pointer to opaque data object 395 * @len: size of object pointed to by @ptr 396 * 397 * Return values: 398 * On success, returns length in bytes of XDR buffer consumed 399 * %-EMSGSIZE on XDR buffer overflow 400 */ 401 static inline ssize_t 402 xdr_stream_encode_opaque(struct xdr_stream *xdr, const void *ptr, size_t len) 403 { 404 size_t count = sizeof(__u32) + xdr_align_size(len); 405 __be32 *p = xdr_reserve_space(xdr, count); 406 407 if (unlikely(!p)) 408 return -EMSGSIZE; 409 xdr_encode_opaque(p, ptr, len); 410 return count; 411 } 412 413 /** 414 * xdr_stream_encode_uint32_array - Encode variable length array of integers 415 * @xdr: pointer to xdr_stream 416 * @array: array of integers 417 * @array_size: number of elements in @array 418 * 419 * Return values: 420 * On success, returns length in bytes of XDR buffer consumed 421 * %-EMSGSIZE on XDR buffer overflow 422 */ 423 static inline ssize_t 424 xdr_stream_encode_uint32_array(struct xdr_stream *xdr, 425 const __u32 *array, size_t array_size) 426 { 427 ssize_t ret = (array_size+1) * sizeof(__u32); 428 __be32 *p = xdr_reserve_space(xdr, ret); 429 430 if (unlikely(!p)) 431 return -EMSGSIZE; 432 *p++ = cpu_to_be32(array_size); 433 for (; array_size > 0; p++, array++, array_size--) 434 *p = cpu_to_be32p(array); 435 return ret; 436 } 437 438 /** 439 * xdr_stream_decode_u32 - Decode a 32-bit integer 440 * @xdr: pointer to xdr_stream 441 * @ptr: location to store integer 442 * 443 * Return values: 444 * %0 on success 445 * %-EBADMSG on XDR buffer overflow 446 */ 447 static inline ssize_t 448 xdr_stream_decode_u32(struct xdr_stream *xdr, __u32 *ptr) 449 { 450 const size_t count = sizeof(*ptr); 451 __be32 *p = xdr_inline_decode(xdr, count); 452 453 if (unlikely(!p)) 454 return -EBADMSG; 455 *ptr = be32_to_cpup(p); 456 return 0; 457 } 458 459 /** 460 * xdr_stream_decode_opaque_fixed - Decode fixed length opaque xdr data 461 * @xdr: pointer to xdr_stream 462 * @ptr: location to store data 463 * @len: size of buffer pointed to by @ptr 464 * 465 * Return values: 466 * On success, returns size of object stored in @ptr 467 * %-EBADMSG on XDR buffer overflow 468 */ 469 static inline ssize_t 470 xdr_stream_decode_opaque_fixed(struct xdr_stream *xdr, void *ptr, size_t len) 471 { 472 __be32 *p = xdr_inline_decode(xdr, len); 473 474 if (unlikely(!p)) 475 return -EBADMSG; 476 xdr_decode_opaque_fixed(p, ptr, len); 477 return len; 478 } 479 480 /** 481 * xdr_stream_decode_opaque_inline - Decode variable length opaque xdr data 482 * @xdr: pointer to xdr_stream 483 * @ptr: location to store pointer to opaque data 484 * @maxlen: maximum acceptable object size 485 * 486 * Note: the pointer stored in @ptr cannot be assumed valid after the XDR 487 * buffer has been destroyed, or even after calling xdr_inline_decode() 488 * on @xdr. It is therefore expected that the object it points to should 489 * be processed immediately. 490 * 491 * Return values: 492 * On success, returns size of object stored in *@ptr 493 * %-EBADMSG on XDR buffer overflow 494 * %-EMSGSIZE if the size of the object would exceed @maxlen 495 */ 496 static inline ssize_t 497 xdr_stream_decode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t maxlen) 498 { 499 __be32 *p; 500 __u32 len; 501 502 *ptr = NULL; 503 if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0)) 504 return -EBADMSG; 505 if (len != 0) { 506 p = xdr_inline_decode(xdr, len); 507 if (unlikely(!p)) 508 return -EBADMSG; 509 if (unlikely(len > maxlen)) 510 return -EMSGSIZE; 511 *ptr = p; 512 } 513 return len; 514 } 515 516 /** 517 * xdr_stream_decode_uint32_array - Decode variable length array of integers 518 * @xdr: pointer to xdr_stream 519 * @array: location to store the integer array or NULL 520 * @array_size: number of elements to store 521 * 522 * Return values: 523 * On success, returns number of elements stored in @array 524 * %-EBADMSG on XDR buffer overflow 525 * %-EMSGSIZE if the size of the array exceeds @array_size 526 */ 527 static inline ssize_t 528 xdr_stream_decode_uint32_array(struct xdr_stream *xdr, 529 __u32 *array, size_t array_size) 530 { 531 __be32 *p; 532 __u32 len; 533 ssize_t retval; 534 535 if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0)) 536 return -EBADMSG; 537 p = xdr_inline_decode(xdr, len * sizeof(*p)); 538 if (unlikely(!p)) 539 return -EBADMSG; 540 if (array == NULL) 541 return len; 542 if (len <= array_size) { 543 if (len < array_size) 544 memset(array+len, 0, (array_size-len)*sizeof(*array)); 545 array_size = len; 546 retval = len; 547 } else 548 retval = -EMSGSIZE; 549 for (; array_size > 0; p++, array++, array_size--) 550 *array = be32_to_cpup(p); 551 return retval; 552 } 553 554 #endif /* _SUNRPC_XDR_H_ */ 555