1 /* 2 * XDR standard data types and function declarations 3 * 4 * Copyright (C) 1995-1997 Olaf Kirch <[email protected]> 5 * 6 * Based on: 7 * RFC 4506 "XDR: External Data Representation Standard", May 2006 8 */ 9 10 #ifndef _SUNRPC_XDR_H_ 11 #define _SUNRPC_XDR_H_ 12 13 #ifdef __KERNEL__ 14 15 #include <linux/uio.h> 16 #include <asm/byteorder.h> 17 #include <asm/unaligned.h> 18 #include <linux/scatterlist.h> 19 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 page ** pages; /* Array of pages */ 55 unsigned int page_base, /* Start of page data */ 56 page_len, /* Length of page data */ 57 flags; /* Flags for data disposition */ 58 #define XDRBUF_READ 0x01 /* target of file read */ 59 #define XDRBUF_WRITE 0x02 /* source of file write */ 60 61 unsigned int buflen, /* Total length of storage buffer */ 62 len; /* Length of XDR encoded message */ 63 }; 64 65 static inline void 66 xdr_buf_init(struct xdr_buf *buf, void *start, size_t len) 67 { 68 buf->head[0].iov_base = start; 69 buf->head[0].iov_len = len; 70 buf->tail[0].iov_len = 0; 71 buf->page_len = 0; 72 buf->flags = 0; 73 buf->len = 0; 74 buf->buflen = len; 75 } 76 77 /* 78 * pre-xdr'ed macros. 79 */ 80 81 #define xdr_zero cpu_to_be32(0) 82 #define xdr_one cpu_to_be32(1) 83 #define xdr_two cpu_to_be32(2) 84 85 #define rpc_success cpu_to_be32(RPC_SUCCESS) 86 #define rpc_prog_unavail cpu_to_be32(RPC_PROG_UNAVAIL) 87 #define rpc_prog_mismatch cpu_to_be32(RPC_PROG_MISMATCH) 88 #define rpc_proc_unavail cpu_to_be32(RPC_PROC_UNAVAIL) 89 #define rpc_garbage_args cpu_to_be32(RPC_GARBAGE_ARGS) 90 #define rpc_system_err cpu_to_be32(RPC_SYSTEM_ERR) 91 #define rpc_drop_reply cpu_to_be32(RPC_DROP_REPLY) 92 93 #define rpc_auth_ok cpu_to_be32(RPC_AUTH_OK) 94 #define rpc_autherr_badcred cpu_to_be32(RPC_AUTH_BADCRED) 95 #define rpc_autherr_rejectedcred cpu_to_be32(RPC_AUTH_REJECTEDCRED) 96 #define rpc_autherr_badverf cpu_to_be32(RPC_AUTH_BADVERF) 97 #define rpc_autherr_rejectedverf cpu_to_be32(RPC_AUTH_REJECTEDVERF) 98 #define rpc_autherr_tooweak cpu_to_be32(RPC_AUTH_TOOWEAK) 99 #define rpcsec_gsserr_credproblem cpu_to_be32(RPCSEC_GSS_CREDPROBLEM) 100 #define rpcsec_gsserr_ctxproblem cpu_to_be32(RPCSEC_GSS_CTXPROBLEM) 101 #define rpc_autherr_oldseqnum cpu_to_be32(101) 102 103 /* 104 * Miscellaneous XDR helper functions 105 */ 106 __be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int len); 107 __be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int len); 108 __be32 *xdr_encode_string(__be32 *p, const char *s); 109 __be32 *xdr_decode_string_inplace(__be32 *p, char **sp, unsigned int *lenp, 110 unsigned int maxlen); 111 __be32 *xdr_encode_netobj(__be32 *p, const struct xdr_netobj *); 112 __be32 *xdr_decode_netobj(__be32 *p, struct xdr_netobj *); 113 114 void xdr_inline_pages(struct xdr_buf *, unsigned int, 115 struct page **, unsigned int, unsigned int); 116 void xdr_terminate_string(struct xdr_buf *, const u32); 117 118 static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len) 119 { 120 return xdr_encode_opaque(p, s, len); 121 } 122 123 /* 124 * Decode 64bit quantities (NFSv3 support) 125 */ 126 static inline __be32 * 127 xdr_encode_hyper(__be32 *p, __u64 val) 128 { 129 put_unaligned_be64(val, p); 130 return p + 2; 131 } 132 133 static inline __be32 * 134 xdr_decode_hyper(__be32 *p, __u64 *valp) 135 { 136 *valp = get_unaligned_be64(p); 137 return p + 2; 138 } 139 140 static inline __be32 * 141 xdr_decode_opaque_fixed(__be32 *p, void *ptr, unsigned int len) 142 { 143 memcpy(ptr, p, len); 144 return p + XDR_QUADLEN(len); 145 } 146 147 /* 148 * Adjust kvec to reflect end of xdr'ed data (RPC client XDR) 149 */ 150 static inline int 151 xdr_adjust_iovec(struct kvec *iov, __be32 *p) 152 { 153 return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base); 154 } 155 156 /* 157 * XDR buffer helper functions 158 */ 159 extern void xdr_shift_buf(struct xdr_buf *, size_t); 160 extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *); 161 extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int); 162 extern void xdr_buf_trim(struct xdr_buf *, unsigned int); 163 extern int xdr_buf_read_netobj(struct xdr_buf *, struct xdr_netobj *, unsigned int); 164 extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int); 165 extern int write_bytes_to_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int); 166 167 /* 168 * Helper structure for copying from an sk_buff. 169 */ 170 struct xdr_skb_reader { 171 struct sk_buff *skb; 172 unsigned int offset; 173 size_t count; 174 __wsum csum; 175 }; 176 177 typedef size_t (*xdr_skb_read_actor)(struct xdr_skb_reader *desc, void *to, size_t len); 178 179 size_t xdr_skb_read_bits(struct xdr_skb_reader *desc, void *to, size_t len); 180 extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *); 181 extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int, 182 struct xdr_skb_reader *, xdr_skb_read_actor); 183 184 extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32); 185 extern int xdr_decode_word(struct xdr_buf *, unsigned int, u32 *); 186 187 struct xdr_array2_desc; 188 typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem); 189 struct xdr_array2_desc { 190 unsigned int elem_size; 191 unsigned int array_len; 192 unsigned int array_maxlen; 193 xdr_xcode_elem_t xcode; 194 }; 195 196 extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base, 197 struct xdr_array2_desc *desc); 198 extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base, 199 struct xdr_array2_desc *desc); 200 extern void _copy_from_pages(char *p, struct page **pages, size_t pgbase, 201 size_t len); 202 203 /* 204 * Provide some simple tools for XDR buffer overflow-checking etc. 205 */ 206 struct xdr_stream { 207 __be32 *p; /* start of available buffer */ 208 struct xdr_buf *buf; /* XDR buffer to read/write */ 209 210 __be32 *end; /* end of available buffer space */ 211 struct kvec *iov; /* pointer to the current kvec */ 212 struct kvec scratch; /* Scratch buffer */ 213 struct page **page_ptr; /* pointer to the current page */ 214 unsigned int nwords; /* Remaining decode buffer length */ 215 }; 216 217 /* 218 * These are the xdr_stream style generic XDR encode and decode functions. 219 */ 220 typedef void (*kxdreproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 221 const void *obj); 222 typedef int (*kxdrdproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr, 223 void *obj); 224 225 extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p); 226 extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes); 227 extern void xdr_commit_encode(struct xdr_stream *xdr); 228 extern void xdr_truncate_encode(struct xdr_stream *xdr, size_t len); 229 extern int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen); 230 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, 231 unsigned int base, unsigned int len); 232 extern unsigned int xdr_stream_pos(const struct xdr_stream *xdr); 233 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p); 234 extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf, 235 struct page **pages, unsigned int len); 236 extern void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen); 237 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes); 238 extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len); 239 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len); 240 extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data); 241 242 /** 243 * xdr_stream_remaining - Return the number of bytes remaining in the stream 244 * @xdr: pointer to struct xdr_stream 245 * 246 * Return value: 247 * Number of bytes remaining in @xdr before xdr->end 248 */ 249 static inline size_t 250 xdr_stream_remaining(const struct xdr_stream *xdr) 251 { 252 return xdr->nwords << 2; 253 } 254 255 ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str, 256 size_t maxlen, gfp_t gfp_flags); 257 /** 258 * xdr_align_size - Calculate padded size of an object 259 * @n: Size of an object being XDR encoded (in bytes) 260 * 261 * Return value: 262 * Size (in bytes) of the object including xdr padding 263 */ 264 static inline size_t 265 xdr_align_size(size_t n) 266 { 267 const size_t mask = sizeof(__u32) - 1; 268 269 return (n + mask) & ~mask; 270 } 271 272 /** 273 * xdr_stream_encode_u32 - Encode a 32-bit integer 274 * @xdr: pointer to xdr_stream 275 * @n: integer to encode 276 * 277 * Return values: 278 * On success, returns length in bytes of XDR buffer consumed 279 * %-EMSGSIZE on XDR buffer overflow 280 */ 281 static inline ssize_t 282 xdr_stream_encode_u32(struct xdr_stream *xdr, __u32 n) 283 { 284 const size_t len = sizeof(n); 285 __be32 *p = xdr_reserve_space(xdr, len); 286 287 if (unlikely(!p)) 288 return -EMSGSIZE; 289 *p = cpu_to_be32(n); 290 return len; 291 } 292 293 /** 294 * xdr_stream_encode_u64 - Encode a 64-bit integer 295 * @xdr: pointer to xdr_stream 296 * @n: 64-bit integer to encode 297 * 298 * Return values: 299 * On success, returns length in bytes of XDR buffer consumed 300 * %-EMSGSIZE on XDR buffer overflow 301 */ 302 static inline ssize_t 303 xdr_stream_encode_u64(struct xdr_stream *xdr, __u64 n) 304 { 305 const size_t len = sizeof(n); 306 __be32 *p = xdr_reserve_space(xdr, len); 307 308 if (unlikely(!p)) 309 return -EMSGSIZE; 310 xdr_encode_hyper(p, n); 311 return len; 312 } 313 314 /** 315 * xdr_stream_encode_opaque_fixed - Encode fixed length opaque xdr data 316 * @xdr: pointer to xdr_stream 317 * @ptr: pointer to opaque data object 318 * @len: size of object pointed to by @ptr 319 * 320 * Return values: 321 * On success, returns length in bytes of XDR buffer consumed 322 * %-EMSGSIZE on XDR buffer overflow 323 */ 324 static inline ssize_t 325 xdr_stream_encode_opaque_fixed(struct xdr_stream *xdr, const void *ptr, size_t len) 326 { 327 __be32 *p = xdr_reserve_space(xdr, len); 328 329 if (unlikely(!p)) 330 return -EMSGSIZE; 331 xdr_encode_opaque_fixed(p, ptr, len); 332 return xdr_align_size(len); 333 } 334 335 /** 336 * xdr_stream_encode_opaque - Encode variable length opaque xdr data 337 * @xdr: pointer to xdr_stream 338 * @ptr: pointer to opaque data object 339 * @len: size of object pointed to by @ptr 340 * 341 * Return values: 342 * On success, returns length in bytes of XDR buffer consumed 343 * %-EMSGSIZE on XDR buffer overflow 344 */ 345 static inline ssize_t 346 xdr_stream_encode_opaque(struct xdr_stream *xdr, const void *ptr, size_t len) 347 { 348 size_t count = sizeof(__u32) + xdr_align_size(len); 349 __be32 *p = xdr_reserve_space(xdr, count); 350 351 if (unlikely(!p)) 352 return -EMSGSIZE; 353 xdr_encode_opaque(p, ptr, len); 354 return count; 355 } 356 357 /** 358 * xdr_stream_decode_u32 - Decode a 32-bit integer 359 * @xdr: pointer to xdr_stream 360 * @ptr: location to store integer 361 * 362 * Return values: 363 * %0 on success 364 * %-EBADMSG on XDR buffer overflow 365 */ 366 static inline ssize_t 367 xdr_stream_decode_u32(struct xdr_stream *xdr, __u32 *ptr) 368 { 369 const size_t count = sizeof(*ptr); 370 __be32 *p = xdr_inline_decode(xdr, count); 371 372 if (unlikely(!p)) 373 return -EBADMSG; 374 *ptr = be32_to_cpup(p); 375 return 0; 376 } 377 378 /** 379 * xdr_stream_decode_opaque_fixed - Decode fixed length opaque xdr data 380 * @xdr: pointer to xdr_stream 381 * @ptr: location to store data 382 * @len: size of buffer pointed to by @ptr 383 * 384 * Return values: 385 * On success, returns size of object stored in @ptr 386 * %-EBADMSG on XDR buffer overflow 387 */ 388 static inline ssize_t 389 xdr_stream_decode_opaque_fixed(struct xdr_stream *xdr, void *ptr, size_t len) 390 { 391 __be32 *p = xdr_inline_decode(xdr, len); 392 393 if (unlikely(!p)) 394 return -EBADMSG; 395 xdr_decode_opaque_fixed(p, ptr, len); 396 return len; 397 } 398 399 /** 400 * xdr_stream_decode_opaque_inline - Decode variable length opaque xdr data 401 * @xdr: pointer to xdr_stream 402 * @ptr: location to store pointer to opaque data 403 * @maxlen: maximum acceptable object size 404 * 405 * Note: the pointer stored in @ptr cannot be assumed valid after the XDR 406 * buffer has been destroyed, or even after calling xdr_inline_decode() 407 * on @xdr. It is therefore expected that the object it points to should 408 * be processed immediately. 409 * 410 * Return values: 411 * On success, returns size of object stored in *@ptr 412 * %-EBADMSG on XDR buffer overflow 413 * %-EMSGSIZE if the size of the object would exceed @maxlen 414 */ 415 static inline ssize_t 416 xdr_stream_decode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t maxlen) 417 { 418 __be32 *p; 419 __u32 len; 420 421 *ptr = NULL; 422 if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0)) 423 return -EBADMSG; 424 if (len != 0) { 425 p = xdr_inline_decode(xdr, len); 426 if (unlikely(!p)) 427 return -EBADMSG; 428 if (unlikely(len > maxlen)) 429 return -EMSGSIZE; 430 *ptr = p; 431 } 432 return len; 433 } 434 #endif /* __KERNEL__ */ 435 436 #endif /* _SUNRPC_XDR_H_ */ 437