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