1 /* $NetBSD: xdr_rec.c,v 1.18 2000/07/06 03:10:35 christos Exp $ */ 2 3 /* 4 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for 5 * unrestricted use provided that this legend is included on all tape 6 * media and as a part of the software program in whole or part. Users 7 * may copy or modify Sun RPC without charge, but are not authorized 8 * to license or distribute it to anyone else except as part of a product or 9 * program developed by the user. 10 * 11 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE 12 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR 13 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE. 14 * 15 * Sun RPC is provided with no support and without any obligation on the 16 * part of Sun Microsystems, Inc. to assist in its use, correction, 17 * modification or enhancement. 18 * 19 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE 20 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC 21 * OR ANY PART THEREOF. 22 * 23 * In no event will Sun Microsystems, Inc. be liable for any lost revenue 24 * or profits or other special, indirect and consequential damages, even if 25 * Sun has been advised of the possibility of such damages. 26 * 27 * Sun Microsystems, Inc. 28 * 2550 Garcia Avenue 29 * Mountain View, California 94043 30 */ 31 32 #include <sys/cdefs.h> 33 #if defined(LIBC_SCCS) && !defined(lint) 34 static char *sccsid = "@(#)xdr_rec.c 1.21 87/08/11 Copyr 1984 Sun Micro"; 35 static char *sccsid = "@(#)xdr_rec.c 2.2 88/08/01 4.0 RPCSRC"; 36 #endif 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 /* 41 * xdr_rec.c, Implements TCP/IP based XDR streams with a "record marking" 42 * layer above tcp (for rpc's use). 43 * 44 * Copyright (C) 1984, Sun Microsystems, Inc. 45 * 46 * These routines interface XDRSTREAMS to a tcp/ip connection. 47 * There is a record marking layer between the xdr stream 48 * and the tcp transport level. A record is composed on one or more 49 * record fragments. A record fragment is a thirty-two bit header followed 50 * by n bytes of data, where n is contained in the header. The header 51 * is represented as a htonl(u_long). Thegh order bit encodes 52 * whether or not the fragment is the last fragment of the record 53 * (1 => fragment is last, 0 => more fragments to follow. 54 * The other 31 bits encode the byte length of the fragment. 55 */ 56 57 #include "namespace.h" 58 #include <sys/types.h> 59 60 #include <netinet/in.h> 61 62 #include <err.h> 63 #include <stdio.h> 64 #include <stdlib.h> 65 #include <string.h> 66 67 #include <rpc/types.h> 68 #include <rpc/xdr.h> 69 #include <rpc/auth.h> 70 #include <rpc/svc.h> 71 #include <rpc/clnt.h> 72 #include <sys/stddef.h> 73 #include "un-namespace.h" 74 75 static bool_t xdrrec_getlong(XDR *, long *); 76 static bool_t xdrrec_putlong(XDR *, const long *); 77 static bool_t xdrrec_getbytes(XDR *, char *, u_int); 78 79 static bool_t xdrrec_putbytes(XDR *, const char *, u_int); 80 static u_int xdrrec_getpos(XDR *); 81 static bool_t xdrrec_setpos(XDR *, u_int); 82 static int32_t *xdrrec_inline(XDR *, u_int); 83 static void xdrrec_destroy(XDR *); 84 85 static const struct xdr_ops xdrrec_ops = { 86 xdrrec_getlong, 87 xdrrec_putlong, 88 xdrrec_getbytes, 89 xdrrec_putbytes, 90 xdrrec_getpos, 91 xdrrec_setpos, 92 xdrrec_inline, 93 xdrrec_destroy 94 }; 95 96 /* 97 * A record is composed of one or more record fragments. 98 * A record fragment is a four-byte header followed by zero to 99 * 2**32-1 bytes. The header is treated as a long unsigned and is 100 * encode/decoded to the network via htonl/ntohl. The low order 31 bits 101 * are a byte count of the fragment. The highest order bit is a boolean: 102 * 1 => this fragment is the last fragment of the record, 103 * 0 => this fragment is followed by more fragment(s). 104 * 105 * The fragment/record machinery is not general; it is constructed to 106 * meet the needs of xdr and rpc based on tcp. 107 */ 108 109 #define LAST_FRAG ((u_int32_t)(1 << 31)) 110 111 typedef struct rec_strm { 112 char *tcp_handle; 113 /* 114 * out-goung bits 115 */ 116 int (*writeit)(void *, void *, int); 117 char *out_base; /* output buffer (points to frag header) */ 118 char *out_finger; /* next output position */ 119 char *out_boundry; /* data cannot up to this address */ 120 u_int32_t *frag_header; /* beginning of curren fragment */ 121 bool_t frag_sent; /* true if buffer sent in middle of record */ 122 /* 123 * in-coming bits 124 */ 125 int (*readit)(void *, void *, int); 126 u_long in_size; /* fixed size of the input buffer */ 127 char *in_base; 128 char *in_finger; /* location of next byte to be had */ 129 char *in_boundry; /* can read up to this location */ 130 long fbtbc; /* fragment bytes to be consumed */ 131 bool_t last_frag; 132 u_int sendsize; 133 u_int recvsize; 134 135 bool_t nonblock; 136 bool_t in_haveheader; 137 u_int32_t in_header; 138 char *in_hdrp; 139 int in_hdrlen; 140 int in_reclen; 141 int in_received; 142 int in_maxrec; 143 } RECSTREAM; 144 145 static u_int fix_buf_size(u_int); 146 static bool_t flush_out(RECSTREAM *, bool_t); 147 static bool_t fill_input_buf(RECSTREAM *); 148 static bool_t get_input_bytes(RECSTREAM *, char *, int); 149 static bool_t set_input_fragment(RECSTREAM *); 150 static bool_t skip_input_bytes(RECSTREAM *, long); 151 static bool_t realloc_stream(RECSTREAM *, int); 152 153 154 /* 155 * Create an xdr handle for xdrrec 156 * xdrrec_create fills in xdrs. Sendsize and recvsize are 157 * send and recv buffer sizes (0 => use default). 158 * tcp_handle is an opaque handle that is passed as the first parameter to 159 * the procedures readit and writeit. Readit and writeit are read and 160 * write respectively. They are like the system 161 * calls expect that they take an opaque handle rather than an fd. 162 */ 163 void 164 xdrrec_create(xdrs, sendsize, recvsize, tcp_handle, readit, writeit) 165 XDR *xdrs; 166 u_int sendsize; 167 u_int recvsize; 168 void *tcp_handle; 169 /* like read, but pass it a tcp_handle, not sock */ 170 int (*readit)(void *, void *, int); 171 /* like write, but pass it a tcp_handle, not sock */ 172 int (*writeit)(void *, void *, int); 173 { 174 RECSTREAM *rstrm = mem_alloc(sizeof(RECSTREAM)); 175 176 if (rstrm == NULL) { 177 warnx("xdrrec_create: out of memory"); 178 /* 179 * This is bad. Should rework xdrrec_create to 180 * return a handle, and in this case return NULL 181 */ 182 return; 183 } 184 rstrm->sendsize = sendsize = fix_buf_size(sendsize); 185 rstrm->out_base = mem_alloc(rstrm->sendsize); 186 if (rstrm->out_base == NULL) { 187 warnx("xdrrec_create: out of memory"); 188 mem_free(rstrm, sizeof(RECSTREAM)); 189 return; 190 } 191 rstrm->recvsize = recvsize = fix_buf_size(recvsize); 192 rstrm->in_base = mem_alloc(recvsize); 193 if (rstrm->in_base == NULL) { 194 warnx("xdrrec_create: out of memory"); 195 mem_free(rstrm->out_base, sendsize); 196 mem_free(rstrm, sizeof(RECSTREAM)); 197 return; 198 } 199 /* 200 * now the rest ... 201 */ 202 xdrs->x_ops = &xdrrec_ops; 203 xdrs->x_private = rstrm; 204 rstrm->tcp_handle = tcp_handle; 205 rstrm->readit = readit; 206 rstrm->writeit = writeit; 207 rstrm->out_finger = rstrm->out_boundry = rstrm->out_base; 208 rstrm->frag_header = (u_int32_t *)(void *)rstrm->out_base; 209 rstrm->out_finger += sizeof(u_int32_t); 210 rstrm->out_boundry += sendsize; 211 rstrm->frag_sent = FALSE; 212 rstrm->in_size = recvsize; 213 rstrm->in_boundry = rstrm->in_base; 214 rstrm->in_finger = (rstrm->in_boundry += recvsize); 215 rstrm->fbtbc = 0; 216 rstrm->last_frag = TRUE; 217 rstrm->in_haveheader = FALSE; 218 rstrm->in_hdrlen = 0; 219 rstrm->in_hdrp = (char *)(void *)&rstrm->in_header; 220 rstrm->nonblock = FALSE; 221 rstrm->in_reclen = 0; 222 rstrm->in_received = 0; 223 } 224 225 226 /* 227 * The reoutines defined below are the xdr ops which will go into the 228 * xdr handle filled in by xdrrec_create. 229 */ 230 231 static bool_t 232 xdrrec_getlong(xdrs, lp) 233 XDR *xdrs; 234 long *lp; 235 { 236 RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); 237 int32_t *buflp = (int32_t *)(void *)(rstrm->in_finger); 238 int32_t mylong; 239 240 /* first try the inline, fast case */ 241 if ((rstrm->fbtbc >= sizeof(int32_t)) && 242 (((long)rstrm->in_boundry - (long)buflp) >= sizeof(int32_t))) { 243 *lp = (long)ntohl((u_int32_t)(*buflp)); 244 rstrm->fbtbc -= sizeof(int32_t); 245 rstrm->in_finger += sizeof(int32_t); 246 } else { 247 if (! xdrrec_getbytes(xdrs, (char *)(void *)&mylong, 248 sizeof(int32_t))) 249 return (FALSE); 250 *lp = (long)ntohl((u_int32_t)mylong); 251 } 252 return (TRUE); 253 } 254 255 static bool_t 256 xdrrec_putlong(xdrs, lp) 257 XDR *xdrs; 258 const long *lp; 259 { 260 RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); 261 int32_t *dest_lp = ((int32_t *)(void *)(rstrm->out_finger)); 262 263 if ((rstrm->out_finger += sizeof(int32_t)) > rstrm->out_boundry) { 264 /* 265 * this case should almost never happen so the code is 266 * inefficient 267 */ 268 rstrm->out_finger -= sizeof(int32_t); 269 rstrm->frag_sent = TRUE; 270 if (! flush_out(rstrm, FALSE)) 271 return (FALSE); 272 dest_lp = ((int32_t *)(void *)(rstrm->out_finger)); 273 rstrm->out_finger += sizeof(int32_t); 274 } 275 *dest_lp = (int32_t)htonl((u_int32_t)(*lp)); 276 return (TRUE); 277 } 278 279 static bool_t /* must manage buffers, fragments, and records */ 280 xdrrec_getbytes(xdrs, addr, len) 281 XDR *xdrs; 282 char *addr; 283 u_int len; 284 { 285 RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); 286 int current; 287 288 while (len > 0) { 289 current = (int)rstrm->fbtbc; 290 if (current == 0) { 291 if (rstrm->last_frag) 292 return (FALSE); 293 if (! set_input_fragment(rstrm)) 294 return (FALSE); 295 continue; 296 } 297 current = (len < current) ? len : current; 298 if (! get_input_bytes(rstrm, addr, current)) 299 return (FALSE); 300 addr += current; 301 rstrm->fbtbc -= current; 302 len -= current; 303 } 304 return (TRUE); 305 } 306 307 static bool_t 308 xdrrec_putbytes(xdrs, addr, len) 309 XDR *xdrs; 310 const char *addr; 311 u_int len; 312 { 313 RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); 314 size_t current; 315 316 while (len > 0) { 317 current = (size_t)((u_long)rstrm->out_boundry - 318 (u_long)rstrm->out_finger); 319 current = (len < current) ? len : current; 320 memmove(rstrm->out_finger, addr, current); 321 rstrm->out_finger += current; 322 addr += current; 323 len -= current; 324 if (rstrm->out_finger == rstrm->out_boundry) { 325 rstrm->frag_sent = TRUE; 326 if (! flush_out(rstrm, FALSE)) 327 return (FALSE); 328 } 329 } 330 return (TRUE); 331 } 332 333 static u_int 334 xdrrec_getpos(xdrs) 335 XDR *xdrs; 336 { 337 RECSTREAM *rstrm = (RECSTREAM *)xdrs->x_private; 338 off_t pos; 339 340 pos = lseek((int)(u_long)rstrm->tcp_handle, (off_t)0, 1); 341 if (pos != -1) 342 switch (xdrs->x_op) { 343 344 case XDR_ENCODE: 345 pos += rstrm->out_finger - rstrm->out_base; 346 break; 347 348 case XDR_DECODE: 349 pos -= rstrm->in_boundry - rstrm->in_finger; 350 break; 351 352 default: 353 pos = (off_t) -1; 354 break; 355 } 356 return ((u_int) pos); 357 } 358 359 static bool_t 360 xdrrec_setpos(xdrs, pos) 361 XDR *xdrs; 362 u_int pos; 363 { 364 RECSTREAM *rstrm = (RECSTREAM *)xdrs->x_private; 365 u_int currpos = xdrrec_getpos(xdrs); 366 int delta = currpos - pos; 367 char *newpos; 368 369 if ((int)currpos != -1) 370 switch (xdrs->x_op) { 371 372 case XDR_ENCODE: 373 newpos = rstrm->out_finger - delta; 374 if ((newpos > (char *)(void *)(rstrm->frag_header)) && 375 (newpos < rstrm->out_boundry)) { 376 rstrm->out_finger = newpos; 377 return (TRUE); 378 } 379 break; 380 381 case XDR_DECODE: 382 newpos = rstrm->in_finger - delta; 383 if ((delta < (int)(rstrm->fbtbc)) && 384 (newpos <= rstrm->in_boundry) && 385 (newpos >= rstrm->in_base)) { 386 rstrm->in_finger = newpos; 387 rstrm->fbtbc -= delta; 388 return (TRUE); 389 } 390 break; 391 392 case XDR_FREE: 393 break; 394 } 395 return (FALSE); 396 } 397 398 static int32_t * 399 xdrrec_inline(xdrs, len) 400 XDR *xdrs; 401 u_int len; 402 { 403 RECSTREAM *rstrm = (RECSTREAM *)xdrs->x_private; 404 int32_t *buf = NULL; 405 406 switch (xdrs->x_op) { 407 408 case XDR_ENCODE: 409 if ((rstrm->out_finger + len) <= rstrm->out_boundry) { 410 buf = (int32_t *)(void *)rstrm->out_finger; 411 rstrm->out_finger += len; 412 } 413 break; 414 415 case XDR_DECODE: 416 if ((len <= rstrm->fbtbc) && 417 ((rstrm->in_finger + len) <= rstrm->in_boundry)) { 418 buf = (int32_t *)(void *)rstrm->in_finger; 419 rstrm->fbtbc -= len; 420 rstrm->in_finger += len; 421 } 422 break; 423 424 case XDR_FREE: 425 break; 426 } 427 return (buf); 428 } 429 430 static void 431 xdrrec_destroy(xdrs) 432 XDR *xdrs; 433 { 434 RECSTREAM *rstrm = (RECSTREAM *)xdrs->x_private; 435 436 mem_free(rstrm->out_base, rstrm->sendsize); 437 mem_free(rstrm->in_base, rstrm->recvsize); 438 mem_free(rstrm, sizeof(RECSTREAM)); 439 } 440 441 442 /* 443 * Exported routines to manage xdr records 444 */ 445 446 /* 447 * Before reading (deserializing from the stream, one should always call 448 * this procedure to guarantee proper record alignment. 449 */ 450 bool_t 451 xdrrec_skiprecord(xdrs) 452 XDR *xdrs; 453 { 454 RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); 455 enum xprt_stat xstat; 456 457 if (rstrm->nonblock) { 458 if (__xdrrec_getrec(xdrs, &xstat, FALSE)) { 459 rstrm->fbtbc = 0; 460 return TRUE; 461 } 462 if (rstrm->in_finger == rstrm->in_boundry && 463 xstat == XPRT_MOREREQS) { 464 rstrm->fbtbc = 0; 465 return TRUE; 466 } 467 return FALSE; 468 } 469 470 while (rstrm->fbtbc > 0 || (! rstrm->last_frag)) { 471 if (! skip_input_bytes(rstrm, rstrm->fbtbc)) 472 return (FALSE); 473 rstrm->fbtbc = 0; 474 if ((! rstrm->last_frag) && (! set_input_fragment(rstrm))) 475 return (FALSE); 476 } 477 rstrm->last_frag = FALSE; 478 return (TRUE); 479 } 480 481 /* 482 * Look ahead function. 483 * Returns TRUE iff there is no more input in the buffer 484 * after consuming the rest of the current record. 485 */ 486 bool_t 487 xdrrec_eof(xdrs) 488 XDR *xdrs; 489 { 490 RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); 491 enum xprt_stat xstat; 492 493 if (rstrm->nonblock) { 494 if (__xdrrec_getrec(xdrs, &xstat, FALSE)) 495 return FALSE; 496 if (!rstrm->in_haveheader && xstat == XPRT_IDLE) 497 return TRUE; 498 return FALSE; 499 } 500 501 while (rstrm->fbtbc > 0 || (! rstrm->last_frag)) { 502 if (! skip_input_bytes(rstrm, rstrm->fbtbc)) 503 return (TRUE); 504 rstrm->fbtbc = 0; 505 if ((! rstrm->last_frag) && (! set_input_fragment(rstrm))) 506 return (TRUE); 507 } 508 if (rstrm->in_finger == rstrm->in_boundry) 509 return (TRUE); 510 return (FALSE); 511 } 512 513 /* 514 * The client must tell the package when an end-of-record has occurred. 515 * The second paraemters tells whether the record should be flushed to the 516 * (output) tcp stream. (This let's the package support batched or 517 * pipelined procedure calls.) TRUE => immmediate flush to tcp connection. 518 */ 519 bool_t 520 xdrrec_endofrecord(xdrs, sendnow) 521 XDR *xdrs; 522 bool_t sendnow; 523 { 524 RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); 525 u_long len; /* fragment length */ 526 527 if (sendnow || rstrm->frag_sent || 528 ((u_long)rstrm->out_finger + sizeof(u_int32_t) >= 529 (u_long)rstrm->out_boundry)) { 530 rstrm->frag_sent = FALSE; 531 return (flush_out(rstrm, TRUE)); 532 } 533 len = (u_long)(rstrm->out_finger) - (u_long)(rstrm->frag_header) - 534 sizeof(u_int32_t); 535 *(rstrm->frag_header) = htonl((u_int32_t)len | LAST_FRAG); 536 rstrm->frag_header = (u_int32_t *)(void *)rstrm->out_finger; 537 rstrm->out_finger += sizeof(u_int32_t); 538 return (TRUE); 539 } 540 541 /* 542 * Fill the stream buffer with a record for a non-blocking connection. 543 * Return true if a record is available in the buffer, false if not. 544 */ 545 bool_t 546 __xdrrec_getrec(xdrs, statp, expectdata) 547 XDR *xdrs; 548 enum xprt_stat *statp; 549 bool_t expectdata; 550 { 551 RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); 552 ssize_t n; 553 int fraglen; 554 555 if (!rstrm->in_haveheader) { 556 n = rstrm->readit(rstrm->tcp_handle, rstrm->in_hdrp, 557 (int)sizeof (rstrm->in_header) - rstrm->in_hdrlen); 558 if (n == 0) { 559 *statp = expectdata ? XPRT_DIED : XPRT_IDLE; 560 return FALSE; 561 } 562 if (n < 0) { 563 *statp = XPRT_DIED; 564 return FALSE; 565 } 566 rstrm->in_hdrp += n; 567 rstrm->in_hdrlen += n; 568 if (rstrm->in_hdrlen < sizeof (rstrm->in_header)) { 569 *statp = XPRT_MOREREQS; 570 return FALSE; 571 } 572 rstrm->in_header = ntohl(rstrm->in_header); 573 fraglen = (int)(rstrm->in_header & ~LAST_FRAG); 574 if (fraglen == 0 || fraglen > rstrm->in_maxrec || 575 (rstrm->in_reclen + fraglen) > rstrm->in_maxrec) { 576 *statp = XPRT_DIED; 577 return FALSE; 578 } 579 rstrm->in_reclen += fraglen; 580 if (rstrm->in_reclen > rstrm->recvsize) 581 realloc_stream(rstrm, rstrm->in_reclen); 582 if (rstrm->in_header & LAST_FRAG) { 583 rstrm->in_header &= ~LAST_FRAG; 584 rstrm->last_frag = TRUE; 585 } 586 } 587 588 n = rstrm->readit(rstrm->tcp_handle, 589 rstrm->in_base + rstrm->in_received, 590 (rstrm->in_reclen - rstrm->in_received)); 591 592 if (n < 0) { 593 *statp = XPRT_DIED; 594 return FALSE; 595 } 596 597 if (n == 0) { 598 *statp = expectdata ? XPRT_DIED : XPRT_IDLE; 599 return FALSE; 600 } 601 602 rstrm->in_received += n; 603 604 if (rstrm->in_received == rstrm->in_reclen) { 605 rstrm->in_haveheader = FALSE; 606 rstrm->in_hdrp = (char *)(void *)&rstrm->in_header; 607 rstrm->in_hdrlen = 0; 608 if (rstrm->last_frag) { 609 rstrm->fbtbc = rstrm->in_reclen; 610 rstrm->in_boundry = rstrm->in_base + rstrm->in_reclen; 611 rstrm->in_finger = rstrm->in_base; 612 rstrm->in_reclen = rstrm->in_received = 0; 613 *statp = XPRT_MOREREQS; 614 return TRUE; 615 } 616 } 617 618 *statp = XPRT_MOREREQS; 619 return FALSE; 620 } 621 622 bool_t 623 __xdrrec_setnonblock(xdrs, maxrec) 624 XDR *xdrs; 625 int maxrec; 626 { 627 RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private); 628 629 rstrm->nonblock = TRUE; 630 if (maxrec == 0) 631 maxrec = rstrm->recvsize; 632 rstrm->in_maxrec = maxrec; 633 return TRUE; 634 } 635 636 /* 637 * Internal useful routines 638 */ 639 static bool_t 640 flush_out(rstrm, eor) 641 RECSTREAM *rstrm; 642 bool_t eor; 643 { 644 u_int32_t eormask = (eor == TRUE) ? LAST_FRAG : 0; 645 u_int32_t len = (u_int32_t)((u_long)(rstrm->out_finger) - 646 (u_long)(rstrm->frag_header) - sizeof(u_int32_t)); 647 648 *(rstrm->frag_header) = htonl(len | eormask); 649 len = (u_int32_t)((u_long)(rstrm->out_finger) - 650 (u_long)(rstrm->out_base)); 651 if ((*(rstrm->writeit))(rstrm->tcp_handle, rstrm->out_base, (int)len) 652 != (int)len) 653 return (FALSE); 654 rstrm->frag_header = (u_int32_t *)(void *)rstrm->out_base; 655 rstrm->out_finger = (char *)rstrm->out_base + sizeof(u_int32_t); 656 return (TRUE); 657 } 658 659 static bool_t /* knows nothing about records! Only about input buffers */ 660 fill_input_buf(rstrm) 661 RECSTREAM *rstrm; 662 { 663 char *where; 664 u_int32_t i; 665 int len; 666 667 if (rstrm->nonblock) 668 return FALSE; 669 670 where = rstrm->in_base; 671 i = (u_int32_t)((u_long)rstrm->in_boundry % BYTES_PER_XDR_UNIT); 672 where += i; 673 len = (u_int32_t)(rstrm->in_size - i); 674 if ((len = (*(rstrm->readit))(rstrm->tcp_handle, where, len)) == -1) 675 return (FALSE); 676 rstrm->in_finger = where; 677 where += len; 678 rstrm->in_boundry = where; 679 return (TRUE); 680 } 681 682 static bool_t /* knows nothing about records! Only about input buffers */ 683 get_input_bytes(rstrm, addr, len) 684 RECSTREAM *rstrm; 685 char *addr; 686 int len; 687 { 688 size_t current; 689 690 if (rstrm->nonblock) { 691 if (len > (int)(rstrm->in_boundry - rstrm->in_finger)) 692 return FALSE; 693 memcpy(addr, rstrm->in_finger, (size_t)len); 694 rstrm->in_finger += len; 695 return TRUE; 696 } 697 698 while (len > 0) { 699 current = (size_t)((long)rstrm->in_boundry - 700 (long)rstrm->in_finger); 701 if (current == 0) { 702 if (! fill_input_buf(rstrm)) 703 return (FALSE); 704 continue; 705 } 706 current = (len < current) ? len : current; 707 memmove(addr, rstrm->in_finger, current); 708 rstrm->in_finger += current; 709 addr += current; 710 len -= current; 711 } 712 return (TRUE); 713 } 714 715 static bool_t /* next two bytes of the input stream are treated as a header */ 716 set_input_fragment(rstrm) 717 RECSTREAM *rstrm; 718 { 719 u_int32_t header; 720 721 if (! get_input_bytes(rstrm, (char *)(void *)&header, sizeof(header))) 722 return (FALSE); 723 header = ntohl(header); 724 rstrm->last_frag = ((header & LAST_FRAG) == 0) ? FALSE : TRUE; 725 /* 726 * Sanity check. Try not to accept wildly incorrect 727 * record sizes. Unfortunately, the only record size 728 * we can positively identify as being 'wildly incorrect' 729 * is zero. Ridiculously large record sizes may look wrong, 730 * but we don't have any way to be certain that they aren't 731 * what the client actually intended to send us. 732 */ 733 if (header == 0) 734 return(FALSE); 735 rstrm->fbtbc = header & (~LAST_FRAG); 736 return (TRUE); 737 } 738 739 static bool_t /* consumes input bytes; knows nothing about records! */ 740 skip_input_bytes(rstrm, cnt) 741 RECSTREAM *rstrm; 742 long cnt; 743 { 744 u_int32_t current; 745 746 while (cnt > 0) { 747 current = (size_t)((long)rstrm->in_boundry - 748 (long)rstrm->in_finger); 749 if (current == 0) { 750 if (! fill_input_buf(rstrm)) 751 return (FALSE); 752 continue; 753 } 754 current = (u_int32_t)((cnt < current) ? cnt : current); 755 rstrm->in_finger += current; 756 cnt -= current; 757 } 758 return (TRUE); 759 } 760 761 static u_int 762 fix_buf_size(s) 763 u_int s; 764 { 765 766 if (s < 100) 767 s = 4000; 768 return (RNDUP(s)); 769 } 770 771 /* 772 * Reallocate the input buffer for a non-block stream. 773 */ 774 static bool_t 775 realloc_stream(rstrm, size) 776 RECSTREAM *rstrm; 777 int size; 778 { 779 ptrdiff_t diff; 780 char *buf; 781 782 if (size > rstrm->recvsize) { 783 buf = realloc(rstrm->in_base, (size_t)size); 784 if (buf == NULL) 785 return FALSE; 786 diff = buf - rstrm->in_base; 787 rstrm->in_finger += diff; 788 rstrm->in_base = buf; 789 rstrm->in_boundry = buf + size; 790 rstrm->recvsize = size; 791 rstrm->in_size = size; 792 } 793 794 return TRUE; 795 } 796