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 /* 21 * Buffer adjustment 22 */ 23 #define XDR_QUADLEN(l) (((l) + 3) >> 2) 24 25 /* 26 * Generic opaque `network object.' At the kernel level, this type 27 * is used only by lockd. 28 */ 29 #define XDR_MAX_NETOBJ 1024 30 struct xdr_netobj { 31 unsigned int len; 32 u8 * data; 33 }; 34 35 /* 36 * This is the legacy generic XDR function. rqstp is either a rpc_rqst 37 * (client side) or svc_rqst pointer (server side). 38 * Encode functions always assume there's enough room in the buffer. 39 */ 40 typedef int (*kxdrproc_t)(void *rqstp, __be32 *data, void *obj); 41 42 /* 43 * Basic structure for transmission/reception of a client XDR message. 44 * Features a header (for a linear buffer containing RPC headers 45 * and the data payload for short messages), and then an array of 46 * pages. 47 * The tail iovec allows you to append data after the page array. Its 48 * main interest is for appending padding to the pages in order to 49 * satisfy the int_32-alignment requirements in RFC1832. 50 * 51 * For the future, we might want to string several of these together 52 * in a list if anybody wants to make use of NFSv4 COMPOUND 53 * operations and/or has a need for scatter/gather involving pages. 54 */ 55 struct xdr_buf { 56 struct kvec head[1], /* RPC header + non-page data */ 57 tail[1]; /* Appended after page data */ 58 59 struct page ** pages; /* Array of pages */ 60 unsigned int page_base, /* Start of page data */ 61 page_len, /* Length of page data */ 62 flags; /* Flags for data disposition */ 63 #define XDRBUF_READ 0x01 /* target of file read */ 64 #define XDRBUF_WRITE 0x02 /* source of file write */ 65 66 unsigned int buflen, /* Total length of storage buffer */ 67 len; /* Length of XDR encoded message */ 68 }; 69 70 static inline void 71 xdr_buf_init(struct xdr_buf *buf, void *start, size_t len) 72 { 73 buf->head[0].iov_base = start; 74 buf->head[0].iov_len = len; 75 buf->tail[0].iov_len = 0; 76 buf->page_len = 0; 77 buf->flags = 0; 78 buf->len = 0; 79 buf->buflen = len; 80 } 81 82 /* 83 * pre-xdr'ed macros. 84 */ 85 86 #define xdr_zero cpu_to_be32(0) 87 #define xdr_one cpu_to_be32(1) 88 #define xdr_two cpu_to_be32(2) 89 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) 97 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) 107 108 /* 109 * Miscellaneous XDR helper functions 110 */ 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 *); 118 119 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); 122 123 static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len) 124 { 125 return xdr_encode_opaque(p, s, len); 126 } 127 128 /* 129 * Decode 64bit quantities (NFSv3 support) 130 */ 131 static inline __be32 * 132 xdr_encode_hyper(__be32 *p, __u64 val) 133 { 134 put_unaligned_be64(val, p); 135 return p + 2; 136 } 137 138 static inline __be32 * 139 xdr_decode_hyper(__be32 *p, __u64 *valp) 140 { 141 *valp = get_unaligned_be64(p); 142 return p + 2; 143 } 144 145 static inline __be32 * 146 xdr_decode_opaque_fixed(__be32 *p, void *ptr, unsigned int len) 147 { 148 memcpy(ptr, p, len); 149 return p + XDR_QUADLEN(len); 150 } 151 152 /* 153 * Adjust kvec to reflect end of xdr'ed data (RPC client XDR) 154 */ 155 static inline int 156 xdr_adjust_iovec(struct kvec *iov, __be32 *p) 157 { 158 return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base); 159 } 160 161 /* 162 * XDR buffer helper functions 163 */ 164 extern void xdr_shift_buf(struct xdr_buf *, size_t); 165 extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *); 166 extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int); 167 extern void xdr_buf_trim(struct xdr_buf *, unsigned int); 168 extern int xdr_buf_read_netobj(struct xdr_buf *, struct xdr_netobj *, unsigned int); 169 extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int); 170 extern int write_bytes_to_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int); 171 172 /* 173 * Helper structure for copying from an sk_buff. 174 */ 175 struct xdr_skb_reader { 176 struct sk_buff *skb; 177 unsigned int offset; 178 size_t count; 179 __wsum csum; 180 }; 181 182 typedef size_t (*xdr_skb_read_actor)(struct xdr_skb_reader *desc, void *to, size_t len); 183 184 size_t xdr_skb_read_bits(struct xdr_skb_reader *desc, void *to, size_t len); 185 extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *); 186 extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int, 187 struct xdr_skb_reader *, xdr_skb_read_actor); 188 189 extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32); 190 extern int xdr_decode_word(struct xdr_buf *, unsigned int, u32 *); 191 192 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; 199 }; 200 201 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, 206 size_t len); 207 208 /* 209 * Provide some simple tools for XDR buffer overflow-checking etc. 210 */ 211 struct xdr_stream { 212 __be32 *p; /* start of available buffer */ 213 struct xdr_buf *buf; /* XDR buffer to read/write */ 214 215 __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 */ 220 }; 221 222 /* 223 * These are the xdr_stream style generic XDR encode and decode functions. 224 */ 225 typedef void (*kxdreproc_t)(void *rqstp, struct xdr_stream *xdr, void *obj); 226 typedef int (*kxdrdproc_t)(void *rqstp, struct xdr_stream *xdr, void *obj); 227 228 extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p); 229 extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes); 230 extern void xdr_commit_encode(struct xdr_stream *xdr); 231 extern void xdr_truncate_encode(struct xdr_stream *xdr, size_t len); 232 extern int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen); 233 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages, 234 unsigned int base, unsigned int len); 235 extern unsigned int xdr_stream_pos(const struct xdr_stream *xdr); 236 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p); 237 extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf, 238 struct page **pages, unsigned int len); 239 extern void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen); 240 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes); 241 extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len); 242 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len); 243 extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data); 244 245 ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str, 246 size_t maxlen, gfp_t gfp_flags); 247 /** 248 * xdr_align_size - Calculate padded size of an object 249 * @n: Size of an object being XDR encoded (in bytes) 250 * 251 * Return value: 252 * Size (in bytes) of the object including xdr padding 253 */ 254 static inline size_t 255 xdr_align_size(size_t n) 256 { 257 const size_t mask = sizeof(__u32) - 1; 258 259 return (n + mask) & ~mask; 260 } 261 262 /** 263 * xdr_stream_encode_u32 - Encode a 32-bit integer 264 * @xdr: pointer to xdr_stream 265 * @n: integer to encode 266 * 267 * Return values: 268 * On success, returns length in bytes of XDR buffer consumed 269 * %-EMSGSIZE on XDR buffer overflow 270 */ 271 static inline ssize_t 272 xdr_stream_encode_u32(struct xdr_stream *xdr, __u32 n) 273 { 274 const size_t len = sizeof(n); 275 __be32 *p = xdr_reserve_space(xdr, len); 276 277 if (unlikely(!p)) 278 return -EMSGSIZE; 279 *p = cpu_to_be32(n); 280 return len; 281 } 282 283 /** 284 * xdr_stream_encode_u64 - Encode a 64-bit integer 285 * @xdr: pointer to xdr_stream 286 * @n: 64-bit integer to encode 287 * 288 * Return values: 289 * On success, returns length in bytes of XDR buffer consumed 290 * %-EMSGSIZE on XDR buffer overflow 291 */ 292 static inline ssize_t 293 xdr_stream_encode_u64(struct xdr_stream *xdr, __u64 n) 294 { 295 const size_t len = sizeof(n); 296 __be32 *p = xdr_reserve_space(xdr, len); 297 298 if (unlikely(!p)) 299 return -EMSGSIZE; 300 xdr_encode_hyper(p, n); 301 return len; 302 } 303 304 /** 305 * xdr_stream_encode_opaque_fixed - Encode fixed length opaque xdr data 306 * @xdr: pointer to xdr_stream 307 * @ptr: pointer to opaque data object 308 * @len: size of object pointed to by @ptr 309 * 310 * Return values: 311 * On success, returns length in bytes of XDR buffer consumed 312 * %-EMSGSIZE on XDR buffer overflow 313 */ 314 static inline ssize_t 315 xdr_stream_encode_opaque_fixed(struct xdr_stream *xdr, const void *ptr, size_t len) 316 { 317 __be32 *p = xdr_reserve_space(xdr, len); 318 319 if (unlikely(!p)) 320 return -EMSGSIZE; 321 xdr_encode_opaque_fixed(p, ptr, len); 322 return xdr_align_size(len); 323 } 324 325 /** 326 * xdr_stream_encode_opaque - Encode variable length opaque xdr data 327 * @xdr: pointer to xdr_stream 328 * @ptr: pointer to opaque data object 329 * @len: size of object pointed to by @ptr 330 * 331 * Return values: 332 * On success, returns length in bytes of XDR buffer consumed 333 * %-EMSGSIZE on XDR buffer overflow 334 */ 335 static inline ssize_t 336 xdr_stream_encode_opaque(struct xdr_stream *xdr, const void *ptr, size_t len) 337 { 338 size_t count = sizeof(__u32) + xdr_align_size(len); 339 __be32 *p = xdr_reserve_space(xdr, count); 340 341 if (unlikely(!p)) 342 return -EMSGSIZE; 343 xdr_encode_opaque(p, ptr, len); 344 return count; 345 } 346 347 /** 348 * xdr_stream_decode_u32 - Decode a 32-bit integer 349 * @xdr: pointer to xdr_stream 350 * @ptr: location to store integer 351 * 352 * Return values: 353 * %0 on success 354 * %-EBADMSG on XDR buffer overflow 355 */ 356 static inline ssize_t 357 xdr_stream_decode_u32(struct xdr_stream *xdr, __u32 *ptr) 358 { 359 const size_t count = sizeof(*ptr); 360 __be32 *p = xdr_inline_decode(xdr, count); 361 362 if (unlikely(!p)) 363 return -EBADMSG; 364 *ptr = be32_to_cpup(p); 365 return 0; 366 } 367 368 /** 369 * xdr_stream_decode_opaque_fixed - Decode fixed length opaque xdr data 370 * @xdr: pointer to xdr_stream 371 * @ptr: location to store data 372 * @len: size of buffer pointed to by @ptr 373 * 374 * Return values: 375 * On success, returns size of object stored in @ptr 376 * %-EBADMSG on XDR buffer overflow 377 */ 378 static inline ssize_t 379 xdr_stream_decode_opaque_fixed(struct xdr_stream *xdr, void *ptr, size_t len) 380 { 381 __be32 *p = xdr_inline_decode(xdr, len); 382 383 if (unlikely(!p)) 384 return -EBADMSG; 385 xdr_decode_opaque_fixed(p, ptr, len); 386 return len; 387 } 388 389 /** 390 * xdr_stream_decode_opaque_inline - Decode variable length opaque xdr data 391 * @xdr: pointer to xdr_stream 392 * @ptr: location to store pointer to opaque data 393 * @maxlen: maximum acceptable object size 394 * 395 * Note: the pointer stored in @ptr cannot be assumed valid after the XDR 396 * buffer has been destroyed, or even after calling xdr_inline_decode() 397 * on @xdr. It is therefore expected that the object it points to should 398 * be processed immediately. 399 * 400 * Return values: 401 * On success, returns size of object stored in *@ptr 402 * %-EBADMSG on XDR buffer overflow 403 * %-EMSGSIZE if the size of the object would exceed @maxlen 404 */ 405 static inline ssize_t 406 xdr_stream_decode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t maxlen) 407 { 408 __be32 *p; 409 __u32 len; 410 411 *ptr = NULL; 412 if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0)) 413 return -EBADMSG; 414 if (len != 0) { 415 p = xdr_inline_decode(xdr, len); 416 if (unlikely(!p)) 417 return -EBADMSG; 418 if (unlikely(len > maxlen)) 419 return -EMSGSIZE; 420 *ptr = p; 421 } 422 return len; 423 } 424 #endif /* __KERNEL__ */ 425 426 #endif /* _SUNRPC_XDR_H_ */ 427