1 /* $NetBSD: getcap.c,v 1.32 2000/01/22 22:19:10 mycroft Exp $ */ 2 3 /*- 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Casey Leedom of Lawrence Livermore National Laboratory. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 #if defined(LIBC_SCCS) && !defined(lint) 41 #if 0 42 static char sccsid[] = "@(#)getcap.c 8.3 (Berkeley) 3/25/94"; 43 #else 44 __RCSID("$NetBSD: getcap.c,v 1.32 2000/01/22 22:19:10 mycroft Exp $"); 45 #endif 46 #endif /* LIBC_SCCS and not lint */ 47 48 #include "namespace.h" 49 #include <sys/types.h> 50 51 #include <assert.h> 52 #include <ctype.h> 53 #include <db.h> 54 #include <errno.h> 55 #include <fcntl.h> 56 #include <limits.h> 57 #include <stdio.h> 58 #include <stdlib.h> 59 #include <string.h> 60 #include <unistd.h> 61 62 #ifdef __weak_alias 63 __weak_alias(cgetcap,_cgetcap) 64 __weak_alias(cgetclose,_cgetclose) 65 __weak_alias(cgetent,_cgetent) 66 __weak_alias(cgetfirst,_cgetfirst) 67 __weak_alias(cgetmatch,_cgetmatch) 68 __weak_alias(cgetnext,_cgetnext) 69 __weak_alias(cgetnum,_cgetnum) 70 __weak_alias(cgetset,_cgetset) 71 __weak_alias(cgetstr,_cgetstr) 72 __weak_alias(cgetustr,_cgetustr) 73 #endif 74 75 #define BFRAG 1024 76 #define BSIZE 1024 77 #define ESC ('[' & 037) /* ASCII ESC */ 78 #define MAX_RECURSION 32 /* maximum getent recursion */ 79 #define SFRAG 100 /* cgetstr mallocs in SFRAG chunks */ 80 81 #define RECOK (char)0 82 #define TCERR (char)1 83 #define SHADOW (char)2 84 85 static size_t topreclen; /* toprec length */ 86 static char *toprec; /* Additional record specified by cgetset() */ 87 static int gottoprec; /* Flag indicating retrieval of toprecord */ 88 89 static int cdbget __P((DB *, char **, const char *)); 90 static int getent __P((char **, size_t *, char **, int, const char *, int, char *)); 91 static int nfcmp __P((char *, char *)); 92 93 /* 94 * Cgetset() allows the addition of a user specified buffer to be added 95 * to the database array, in effect "pushing" the buffer on top of the 96 * virtual database. 0 is returned on success, -1 on failure. 97 */ 98 int 99 cgetset(ent) 100 const char *ent; 101 { 102 const char *source, *check; 103 char *dest; 104 105 if (ent == NULL) { 106 if (toprec) 107 free(toprec); 108 toprec = NULL; 109 topreclen = 0; 110 return (0); 111 } 112 topreclen = strlen(ent); 113 if ((toprec = malloc (topreclen + 1)) == NULL) { 114 errno = ENOMEM; 115 return (-1); 116 } 117 gottoprec = 0; 118 119 source=ent; 120 dest=toprec; 121 while (*source) { /* Strip whitespace */ 122 *dest++ = *source++; /* Do not check first field */ 123 while (*source == ':') { 124 check=source+1; 125 while (*check && (isspace((unsigned char)*check) || 126 (*check=='\\' && isspace((unsigned char)check[1])))) 127 ++check; 128 if( *check == ':' ) 129 source=check; 130 else 131 break; 132 133 } 134 } 135 *dest=0; 136 137 return (0); 138 } 139 140 /* 141 * Cgetcap searches the capability record buf for the capability cap with 142 * type `type'. A pointer to the value of cap is returned on success, NULL 143 * if the requested capability couldn't be found. 144 * 145 * Specifying a type of ':' means that nothing should follow cap (:cap:). 146 * In this case a pointer to the terminating ':' or NUL will be returned if 147 * cap is found. 148 * 149 * If (cap, '@') or (cap, terminator, '@') is found before (cap, terminator) 150 * return NULL. 151 */ 152 char * 153 cgetcap(buf, cap, type) 154 char *buf; 155 const char *cap; 156 int type; 157 { 158 char *bp; 159 const char *cp; 160 161 _DIAGASSERT(buf != NULL); 162 _DIAGASSERT(cap != NULL); 163 164 bp = buf; 165 for (;;) { 166 /* 167 * Skip past the current capability field - it's either the 168 * name field if this is the first time through the loop, or 169 * the remainder of a field whose name failed to match cap. 170 */ 171 for (;;) 172 if (*bp == '\0') 173 return (NULL); 174 else 175 if (*bp++ == ':') 176 break; 177 178 /* 179 * Try to match (cap, type) in buf. 180 */ 181 for (cp = cap; *cp == *bp && *bp != '\0'; cp++, bp++) 182 continue; 183 if (*cp != '\0') 184 continue; 185 if (*bp == '@') 186 return (NULL); 187 if (type == ':') { 188 if (*bp != '\0' && *bp != ':') 189 continue; 190 return(bp); 191 } 192 if (*bp != type) 193 continue; 194 bp++; 195 return (*bp == '@' ? NULL : bp); 196 } 197 /* NOTREACHED */ 198 } 199 200 /* 201 * Cgetent extracts the capability record name from the NULL terminated file 202 * array db_array and returns a pointer to a malloc'd copy of it in buf. 203 * Buf must be retained through all subsequent calls to cgetcap, cgetnum, 204 * cgetflag, and cgetstr, but may then be free'd. 0 is returned on success, 205 * -1 if the requested record couldn't be found, -2 if a system error was 206 * encountered (couldn't open/read a file, etc.), and -3 if a potential 207 * reference loop is detected. 208 */ 209 int 210 cgetent(buf, db_array, name) 211 char **buf, **db_array; 212 const char *name; 213 { 214 size_t dummy; 215 216 _DIAGASSERT(buf != NULL); 217 _DIAGASSERT(db_array != NULL); 218 _DIAGASSERT(name != NULL); 219 220 return (getent(buf, &dummy, db_array, -1, name, 0, NULL)); 221 } 222 223 /* 224 * Getent implements the functions of cgetent. If fd is non-negative, 225 * *db_array has already been opened and fd is the open file descriptor. We 226 * do this to save time and avoid using up file descriptors for tc= 227 * recursions. 228 * 229 * Getent returns the same success/failure codes as cgetent. On success, a 230 * pointer to a malloc'ed capability record with all tc= capabilities fully 231 * expanded and its length (not including trailing ASCII NUL) are left in 232 * *cap and *len. 233 * 234 * Basic algorithm: 235 * + Allocate memory incrementally as needed in chunks of size BFRAG 236 * for capability buffer. 237 * + Recurse for each tc=name and interpolate result. Stop when all 238 * names interpolated, a name can't be found, or depth exceeds 239 * MAX_RECURSION. 240 */ 241 static int 242 getent(cap, len, db_array, fd, name, depth, nfield) 243 char **cap, **db_array, *nfield; 244 const char *name; 245 size_t *len; 246 int fd, depth; 247 { 248 DB *capdbp; 249 char *r_end, *rp = NULL, **db_p; /* pacify gcc */ 250 int myfd = 0, eof, foundit, retval; 251 size_t clen; 252 char *record, *cbuf; 253 int tc_not_resolved; 254 char pbuf[_POSIX_PATH_MAX]; 255 256 _DIAGASSERT(cap != NULL); 257 _DIAGASSERT(len != NULL); 258 _DIAGASSERT(db_array != NULL); 259 /* fd may be -1 */ 260 _DIAGASSERT(name != NULL); 261 /* nfield may be NULL */ 262 263 /* 264 * Return with ``loop detected'' error if we've recursed more than 265 * MAX_RECURSION times. 266 */ 267 if (depth > MAX_RECURSION) 268 return (-3); 269 270 /* 271 * Check if we have a top record from cgetset(). 272 */ 273 if (depth == 0 && toprec != NULL && cgetmatch(toprec, name) == 0) { 274 if ((record = malloc (topreclen + BFRAG)) == NULL) { 275 errno = ENOMEM; 276 return (-2); 277 } 278 (void)strcpy(record, toprec); /* XXX: strcpy is safe */ 279 db_p = db_array; 280 rp = record + topreclen + 1; 281 r_end = rp + BFRAG; 282 goto tc_exp; 283 } 284 /* 285 * Allocate first chunk of memory. 286 */ 287 if ((record = malloc(BFRAG)) == NULL) { 288 errno = ENOMEM; 289 return (-2); 290 } 291 r_end = record + BFRAG; 292 foundit = 0; 293 /* 294 * Loop through database array until finding the record. 295 */ 296 297 for (db_p = db_array; *db_p != NULL; db_p++) { 298 eof = 0; 299 300 /* 301 * Open database if not already open. 302 */ 303 304 if (fd >= 0) { 305 (void)lseek(fd, (off_t)0, SEEK_SET); 306 } else { 307 (void)snprintf(pbuf, sizeof(pbuf), "%s.db", *db_p); 308 if ((capdbp = dbopen(pbuf, O_RDONLY, 0, DB_HASH, 0)) 309 != NULL) { 310 free(record); 311 retval = cdbget(capdbp, &record, name); 312 if (retval < 0) { 313 /* no record available */ 314 (void)capdbp->close(capdbp); 315 return (retval); 316 } 317 /* save the data; close frees it */ 318 clen = strlen(record); 319 cbuf = malloc(clen + 1); 320 memmove(cbuf, record, clen + 1); 321 if (capdbp->close(capdbp) < 0) { 322 int serrno = errno; 323 324 free(cbuf); 325 errno = serrno; 326 return (-2); 327 } 328 *len = clen; 329 *cap = cbuf; 330 return (retval); 331 } else { 332 fd = open(*db_p, O_RDONLY, 0); 333 if (fd < 0) { 334 /* No error on unfound file. */ 335 continue; 336 } 337 myfd = 1; 338 } 339 } 340 /* 341 * Find the requested capability record ... 342 */ 343 { 344 char buf[BUFSIZ]; 345 char *b_end, *bp, *cp; 346 int c, slash; 347 348 /* 349 * Loop invariants: 350 * There is always room for one more character in record. 351 * R_end always points just past end of record. 352 * Rp always points just past last character in record. 353 * B_end always points just past last character in buf. 354 * Bp always points at next character in buf. 355 * Cp remembers where the last colon was. 356 */ 357 b_end = buf; 358 bp = buf; 359 cp = 0; 360 slash = 0; 361 for (;;) { 362 363 /* 364 * Read in a line implementing (\, newline) 365 * line continuation. 366 */ 367 rp = record; 368 for (;;) { 369 if (bp >= b_end) { 370 int n; 371 372 n = read(fd, buf, sizeof(buf)); 373 if (n <= 0) { 374 if (myfd) 375 (void)close(fd); 376 if (n < 0) { 377 int serrno = errno; 378 379 free(record); 380 errno = serrno; 381 return (-2); 382 } else { 383 fd = -1; 384 eof = 1; 385 break; 386 } 387 } 388 b_end = buf+n; 389 bp = buf; 390 } 391 392 c = *bp++; 393 if (c == '\n') { 394 if (slash) { 395 slash = 0; 396 rp--; 397 continue; 398 } else 399 break; 400 } 401 if (slash) { 402 slash = 0; 403 cp = 0; 404 } 405 if (c == ':') { 406 /* 407 * If the field was `empty' (i.e. 408 * contained only white space), back up 409 * to the colon (eliminating the 410 * field). 411 */ 412 if (cp) 413 rp = cp; 414 else 415 cp = rp; 416 } else if (c == '\\') { 417 slash = 1; 418 } else if (c != ' ' && c != '\t') { 419 /* 420 * Forget where the colon was, as this 421 * is not an empty field. 422 */ 423 cp = 0; 424 } 425 *rp++ = c; 426 427 /* 428 * Enforce loop invariant: if no room 429 * left in record buffer, try to get 430 * some more. 431 */ 432 if (rp >= r_end) { 433 u_int pos; 434 size_t newsize; 435 436 pos = rp - record; 437 newsize = r_end - record + BFRAG; 438 record = realloc(record, newsize); 439 if (record == NULL) { 440 if (myfd) 441 (void)close(fd); 442 errno = ENOMEM; 443 return (-2); 444 } 445 r_end = record + newsize; 446 rp = record + pos; 447 } 448 } 449 /* Eliminate any white space after the last colon. */ 450 if (cp) 451 rp = cp + 1; 452 /* Loop invariant lets us do this. */ 453 *rp++ = '\0'; 454 455 /* 456 * If encountered eof check next file. 457 */ 458 if (eof) 459 break; 460 461 /* 462 * Toss blank lines and comments. 463 */ 464 if (*record == '\0' || *record == '#') 465 continue; 466 467 /* 468 * See if this is the record we want ... 469 */ 470 if (cgetmatch(record, name) == 0) { 471 if (nfield == NULL || !nfcmp(nfield, record)) { 472 foundit = 1; 473 break; /* found it! */ 474 } 475 } 476 } 477 } 478 if (foundit) 479 break; 480 } 481 482 if (!foundit) 483 return (-1); 484 485 /* 486 * Got the capability record, but now we have to expand all tc=name 487 * references in it ... 488 */ 489 tc_exp: { 490 char *newicap, *s; 491 size_t ilen, newilen; 492 int diff, iret, tclen; 493 char *icap, *scan, *tc, *tcstart, *tcend; 494 495 /* 496 * Loop invariants: 497 * There is room for one more character in record. 498 * R_end points just past end of record. 499 * Rp points just past last character in record. 500 * Scan points at remainder of record that needs to be 501 * scanned for tc=name constructs. 502 */ 503 scan = record; 504 tc_not_resolved = 0; 505 for (;;) { 506 if ((tc = cgetcap(scan, "tc", '=')) == NULL) 507 break; 508 509 /* 510 * Find end of tc=name and stomp on the trailing `:' 511 * (if present) so we can use it to call ourselves. 512 */ 513 s = tc; 514 for (;;) 515 if (*s == '\0') 516 break; 517 else 518 if (*s++ == ':') { 519 *(s - 1) = '\0'; 520 break; 521 } 522 tcstart = tc - 3; 523 tclen = s - tcstart; 524 tcend = s; 525 526 iret = getent(&icap, &ilen, db_p, fd, tc, depth+1, 527 NULL); 528 newicap = icap; /* Put into a register. */ 529 newilen = ilen; 530 if (iret != 0) { 531 /* an error */ 532 if (iret < -1) { 533 if (myfd) 534 (void)close(fd); 535 free(record); 536 return (iret); 537 } 538 if (iret == 1) 539 tc_not_resolved = 1; 540 /* couldn't resolve tc */ 541 if (iret == -1) { 542 *(s - 1) = ':'; 543 scan = s - 1; 544 tc_not_resolved = 1; 545 continue; 546 547 } 548 } 549 /* not interested in name field of tc'ed record */ 550 s = newicap; 551 for (;;) 552 if (*s == '\0') 553 break; 554 else 555 if (*s++ == ':') 556 break; 557 newilen -= s - newicap; 558 newicap = s; 559 560 /* make sure interpolated record is `:'-terminated */ 561 s += newilen; 562 if (*(s-1) != ':') { 563 *s = ':'; /* overwrite NUL with : */ 564 newilen++; 565 } 566 567 /* 568 * Make sure there's enough room to insert the 569 * new record. 570 */ 571 diff = newilen - tclen; 572 if (diff >= r_end - rp) { 573 u_int pos, tcpos, tcposend; 574 size_t newsize; 575 576 pos = rp - record; 577 newsize = r_end - record + diff + BFRAG; 578 tcpos = tcstart - record; 579 tcposend = tcend - record; 580 record = realloc(record, newsize); 581 if (record == NULL) { 582 if (myfd) 583 (void)close(fd); 584 free(icap); 585 errno = ENOMEM; 586 return (-2); 587 } 588 r_end = record + newsize; 589 rp = record + pos; 590 tcstart = record + tcpos; 591 tcend = record + tcposend; 592 } 593 594 /* 595 * Insert tc'ed record into our record. 596 */ 597 s = tcstart + newilen; 598 memmove(s, tcend, (size_t)(rp - tcend)); 599 memmove(tcstart, newicap, newilen); 600 rp += diff; 601 free(icap); 602 603 /* 604 * Start scan on `:' so next cgetcap works properly 605 * (cgetcap always skips first field). 606 */ 607 scan = s-1; 608 } 609 610 } 611 /* 612 * Close file (if we opened it), give back any extra memory, and 613 * return capability, length and success. 614 */ 615 if (myfd) 616 (void)close(fd); 617 *len = rp - record - 1; /* don't count NUL */ 618 if (r_end > rp) 619 if ((record = 620 realloc(record, (size_t)(rp - record))) == NULL) { 621 errno = ENOMEM; 622 return (-2); 623 } 624 625 *cap = record; 626 if (tc_not_resolved) 627 return (1); 628 return (0); 629 } 630 631 static int 632 cdbget(capdbp, bp, name) 633 DB *capdbp; 634 char **bp; 635 const char *name; 636 { 637 DBT key; 638 DBT data; 639 640 _DIAGASSERT(capdbp != NULL); 641 _DIAGASSERT(bp != NULL); 642 _DIAGASSERT(name != NULL); 643 644 /* LINTED key is not modified */ 645 key.data = (char *)name; 646 key.size = strlen(name); 647 648 for (;;) { 649 /* Get the reference. */ 650 switch(capdbp->get(capdbp, &key, &data, 0)) { 651 case -1: 652 return (-2); 653 case 1: 654 return (-1); 655 } 656 657 /* If not an index to another record, leave. */ 658 if (((char *)data.data)[0] != SHADOW) 659 break; 660 661 key.data = (char *)data.data + 1; 662 key.size = data.size - 1; 663 } 664 665 *bp = (char *)data.data + 1; 666 return (((char *)(data.data))[0] == TCERR ? 1 : 0); 667 } 668 669 /* 670 * Cgetmatch will return 0 if name is one of the names of the capability 671 * record buf, -1 if not. 672 */ 673 int 674 cgetmatch(buf, name) 675 const char *buf, *name; 676 { 677 const char *np, *bp; 678 679 _DIAGASSERT(buf != NULL); 680 _DIAGASSERT(name != NULL); 681 682 /* 683 * Start search at beginning of record. 684 */ 685 bp = buf; 686 for (;;) { 687 /* 688 * Try to match a record name. 689 */ 690 np = name; 691 for (;;) 692 if (*np == '\0') { 693 if (*bp == '|' || *bp == ':' || *bp == '\0') 694 return (0); 695 else 696 break; 697 } else 698 if (*bp++ != *np++) 699 break; 700 701 /* 702 * Match failed, skip to next name in record. 703 */ 704 bp--; /* a '|' or ':' may have stopped the match */ 705 for (;;) 706 if (*bp == '\0' || *bp == ':') 707 return (-1); /* match failed totally */ 708 else 709 if (*bp++ == '|') 710 break; /* found next name */ 711 } 712 } 713 714 int 715 cgetfirst(buf, db_array) 716 char **buf, **db_array; 717 { 718 719 _DIAGASSERT(buf != NULL); 720 _DIAGASSERT(db_array != NULL); 721 722 (void)cgetclose(); 723 return (cgetnext(buf, db_array)); 724 } 725 726 static FILE *pfp; 727 static int slash; 728 static char **dbp; 729 730 int 731 cgetclose() 732 { 733 if (pfp != NULL) { 734 (void)fclose(pfp); 735 pfp = NULL; 736 } 737 dbp = NULL; 738 gottoprec = 0; 739 slash = 0; 740 return(0); 741 } 742 743 /* 744 * Cgetnext() gets either the first or next entry in the logical database 745 * specified by db_array. It returns 0 upon completion of the database, 1 746 * upon returning an entry with more remaining, and -1 if an error occurs. 747 */ 748 int 749 cgetnext(bp, db_array) 750 char **bp; 751 char **db_array; 752 { 753 size_t len; 754 int status, done; 755 char *cp, *line, *rp, *np, buf[BSIZE], nbuf[BSIZE]; 756 size_t dummy; 757 758 _DIAGASSERT(bp != NULL); 759 _DIAGASSERT(db_array != NULL); 760 761 if (dbp == NULL) 762 dbp = db_array; 763 764 if (pfp == NULL && (pfp = fopen(*dbp, "r")) == NULL) { 765 (void)cgetclose(); 766 return (-1); 767 } 768 for(;;) { 769 if (toprec && !gottoprec) { 770 gottoprec = 1; 771 line = toprec; 772 } else { 773 line = fgetln(pfp, &len); 774 if (line == NULL && pfp) { 775 if (ferror(pfp)) { 776 (void)cgetclose(); 777 return (-1); 778 } else { 779 (void)fclose(pfp); 780 pfp = NULL; 781 if (*++dbp == NULL) { 782 (void)cgetclose(); 783 return (0); 784 } else if ((pfp = 785 fopen(*dbp, "r")) == NULL) { 786 (void)cgetclose(); 787 return (-1); 788 } else 789 continue; 790 } 791 } else 792 line[len - 1] = '\0'; 793 if (len == 1) { 794 slash = 0; 795 continue; 796 } 797 if (isspace((unsigned char)*line) || 798 *line == ':' || *line == '#' || slash) { 799 if (line[len - 2] == '\\') 800 slash = 1; 801 else 802 slash = 0; 803 continue; 804 } 805 if (line[len - 2] == '\\') 806 slash = 1; 807 else 808 slash = 0; 809 } 810 811 812 /* 813 * Line points to a name line. 814 */ 815 done = 0; 816 np = nbuf; 817 for (;;) { 818 for (cp = line; *cp != '\0'; cp++) { 819 if (*cp == ':') { 820 *np++ = ':'; 821 done = 1; 822 break; 823 } 824 if (*cp == '\\') 825 break; 826 *np++ = *cp; 827 } 828 if (done) { 829 *np = '\0'; 830 break; 831 } else { /* name field extends beyond the line */ 832 line = fgetln(pfp, &len); 833 if (line == NULL && pfp) { 834 if (ferror(pfp)) { 835 (void)cgetclose(); 836 return (-1); 837 } 838 (void)fclose(pfp); 839 pfp = NULL; 840 *np = '\0'; 841 break; 842 } else 843 line[len - 1] = '\0'; 844 } 845 } 846 rp = buf; 847 for(cp = nbuf; *cp != '\0'; cp++) 848 if (*cp == '|' || *cp == ':') 849 break; 850 else 851 *rp++ = *cp; 852 853 *rp = '\0'; 854 /* 855 * XXX 856 * Last argument of getent here should be nbuf if we want true 857 * sequential access in the case of duplicates. 858 * With NULL, getent will return the first entry found 859 * rather than the duplicate entry record. This is a 860 * matter of semantics that should be resolved. 861 */ 862 status = getent(bp, &dummy, db_array, -1, buf, 0, NULL); 863 if (status == -2 || status == -3) 864 (void)cgetclose(); 865 866 return (status + 1); 867 } 868 /* NOTREACHED */ 869 } 870 871 /* 872 * Cgetstr retrieves the value of the string capability cap from the 873 * capability record pointed to by buf. A pointer to a decoded, NUL 874 * terminated, malloc'd copy of the string is returned in the char * 875 * pointed to by str. The length of the string not including the trailing 876 * NUL is returned on success, -1 if the requested string capability 877 * couldn't be found, -2 if a system error was encountered (storage 878 * allocation failure). 879 */ 880 int 881 cgetstr(buf, cap, str) 882 char *buf; 883 const char *cap; 884 char **str; 885 { 886 u_int m_room; 887 const char *bp; 888 char *mp; 889 int len; 890 char *mem; 891 892 _DIAGASSERT(buf != NULL); 893 _DIAGASSERT(cap != NULL); 894 _DIAGASSERT(str != NULL); 895 896 /* 897 * Find string capability cap 898 */ 899 bp = cgetcap(buf, cap, '='); 900 if (bp == NULL) 901 return (-1); 902 903 /* 904 * Conversion / storage allocation loop ... Allocate memory in 905 * chunks SFRAG in size. 906 */ 907 if ((mem = malloc(SFRAG)) == NULL) { 908 errno = ENOMEM; 909 return (-2); /* couldn't even allocate the first fragment */ 910 } 911 m_room = SFRAG; 912 mp = mem; 913 914 while (*bp != ':' && *bp != '\0') { 915 /* 916 * Loop invariants: 917 * There is always room for one more character in mem. 918 * Mp always points just past last character in mem. 919 * Bp always points at next character in buf. 920 */ 921 if (*bp == '^') { 922 bp++; 923 if (*bp == ':' || *bp == '\0') 924 break; /* drop unfinished escape */ 925 *mp++ = *bp++ & 037; 926 } else if (*bp == '\\') { 927 bp++; 928 if (*bp == ':' || *bp == '\0') 929 break; /* drop unfinished escape */ 930 if ('0' <= *bp && *bp <= '7') { 931 int n, i; 932 933 n = 0; 934 i = 3; /* maximum of three octal digits */ 935 do { 936 n = n * 8 + (*bp++ - '0'); 937 } while (--i && '0' <= *bp && *bp <= '7'); 938 *mp++ = n; 939 } 940 else switch (*bp++) { 941 case 'b': case 'B': 942 *mp++ = '\b'; 943 break; 944 case 't': case 'T': 945 *mp++ = '\t'; 946 break; 947 case 'n': case 'N': 948 *mp++ = '\n'; 949 break; 950 case 'f': case 'F': 951 *mp++ = '\f'; 952 break; 953 case 'r': case 'R': 954 *mp++ = '\r'; 955 break; 956 case 'e': case 'E': 957 *mp++ = ESC; 958 break; 959 case 'c': case 'C': 960 *mp++ = ':'; 961 break; 962 default: 963 /* 964 * Catches '\', '^', and 965 * everything else. 966 */ 967 *mp++ = *(bp-1); 968 break; 969 } 970 } else 971 *mp++ = *bp++; 972 m_room--; 973 974 /* 975 * Enforce loop invariant: if no room left in current 976 * buffer, try to get some more. 977 */ 978 if (m_room == 0) { 979 size_t size = mp - mem; 980 981 if ((mem = realloc(mem, size + SFRAG)) == NULL) 982 return (-2); 983 m_room = SFRAG; 984 mp = mem + size; 985 } 986 } 987 *mp++ = '\0'; /* loop invariant let's us do this */ 988 m_room--; 989 len = mp - mem - 1; 990 991 /* 992 * Give back any extra memory and return value and success. 993 */ 994 if (m_room != 0) 995 if ((mem = realloc(mem, (size_t)(mp - mem))) == NULL) 996 return (-2); 997 *str = mem; 998 return (len); 999 } 1000 1001 /* 1002 * Cgetustr retrieves the value of the string capability cap from the 1003 * capability record pointed to by buf. The difference between cgetustr() 1004 * and cgetstr() is that cgetustr does not decode escapes but rather treats 1005 * all characters literally. A pointer to a NUL terminated malloc'd 1006 * copy of the string is returned in the char pointed to by str. The 1007 * length of the string not including the trailing NUL is returned on success, 1008 * -1 if the requested string capability couldn't be found, -2 if a system 1009 * error was encountered (storage allocation failure). 1010 */ 1011 int 1012 cgetustr(buf, cap, str) 1013 char *buf; 1014 const char *cap; 1015 char **str; 1016 { 1017 u_int m_room; 1018 const char *bp; 1019 char *mp; 1020 int len; 1021 char *mem; 1022 1023 _DIAGASSERT(buf != NULL); 1024 _DIAGASSERT(cap != NULL); 1025 _DIAGASSERT(str != NULL); 1026 1027 /* 1028 * Find string capability cap 1029 */ 1030 if ((bp = cgetcap(buf, cap, '=')) == NULL) 1031 return (-1); 1032 1033 /* 1034 * Conversion / storage allocation loop ... Allocate memory in 1035 * chunks SFRAG in size. 1036 */ 1037 if ((mem = malloc(SFRAG)) == NULL) { 1038 errno = ENOMEM; 1039 return (-2); /* couldn't even allocate the first fragment */ 1040 } 1041 m_room = SFRAG; 1042 mp = mem; 1043 1044 while (*bp != ':' && *bp != '\0') { 1045 /* 1046 * Loop invariants: 1047 * There is always room for one more character in mem. 1048 * Mp always points just past last character in mem. 1049 * Bp always points at next character in buf. 1050 */ 1051 *mp++ = *bp++; 1052 m_room--; 1053 1054 /* 1055 * Enforce loop invariant: if no room left in current 1056 * buffer, try to get some more. 1057 */ 1058 if (m_room == 0) { 1059 size_t size = mp - mem; 1060 1061 if ((mem = realloc(mem, size + SFRAG)) == NULL) 1062 return (-2); 1063 m_room = SFRAG; 1064 mp = mem + size; 1065 } 1066 } 1067 *mp++ = '\0'; /* loop invariant let's us do this */ 1068 m_room--; 1069 len = mp - mem - 1; 1070 1071 /* 1072 * Give back any extra memory and return value and success. 1073 */ 1074 if (m_room != 0) 1075 if ((mem = realloc(mem, (size_t)(mp - mem))) == NULL) 1076 return (-2); 1077 *str = mem; 1078 return (len); 1079 } 1080 1081 /* 1082 * Cgetnum retrieves the value of the numeric capability cap from the 1083 * capability record pointed to by buf. The numeric value is returned in 1084 * the long pointed to by num. 0 is returned on success, -1 if the requested 1085 * numeric capability couldn't be found. 1086 */ 1087 int 1088 cgetnum(buf, cap, num) 1089 char *buf; 1090 const char *cap; 1091 long *num; 1092 { 1093 long n; 1094 int base, digit; 1095 const char *bp; 1096 1097 _DIAGASSERT(buf != NULL); 1098 _DIAGASSERT(cap != NULL); 1099 _DIAGASSERT(num != NULL); 1100 1101 /* 1102 * Find numeric capability cap 1103 */ 1104 bp = cgetcap(buf, cap, '#'); 1105 if (bp == NULL) 1106 return (-1); 1107 1108 /* 1109 * Look at value and determine numeric base: 1110 * 0x... or 0X... hexadecimal, 1111 * else 0... octal, 1112 * else decimal. 1113 */ 1114 if (*bp == '0') { 1115 bp++; 1116 if (*bp == 'x' || *bp == 'X') { 1117 bp++; 1118 base = 16; 1119 } else 1120 base = 8; 1121 } else 1122 base = 10; 1123 1124 /* 1125 * Conversion loop ... 1126 */ 1127 n = 0; 1128 for (;;) { 1129 if ('0' <= *bp && *bp <= '9') 1130 digit = *bp - '0'; 1131 else if ('a' <= *bp && *bp <= 'f') 1132 digit = 10 + *bp - 'a'; 1133 else if ('A' <= *bp && *bp <= 'F') 1134 digit = 10 + *bp - 'A'; 1135 else 1136 break; 1137 1138 if (digit >= base) 1139 break; 1140 1141 n = n * base + digit; 1142 bp++; 1143 } 1144 1145 /* 1146 * Return value and success. 1147 */ 1148 *num = n; 1149 return (0); 1150 } 1151 1152 1153 /* 1154 * Compare name field of record. 1155 */ 1156 static int 1157 nfcmp(nf, rec) 1158 char *nf, *rec; 1159 { 1160 char *cp, tmp; 1161 int ret; 1162 1163 _DIAGASSERT(nf != NULL); 1164 _DIAGASSERT(rec != NULL); 1165 1166 for (cp = rec; *cp != ':'; cp++) 1167 ; 1168 1169 tmp = *(cp + 1); 1170 *(cp + 1) = '\0'; 1171 ret = strcmp(nf, rec); 1172 *(cp + 1) = tmp; 1173 1174 return (ret); 1175 } 1176