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 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 */ 32 33#if defined(LIBC_SCCS) && !defined(lint) 34static char sccsid[] = "@(#)getcap.c 8.3 (Berkeley) 3/25/94"; 35#endif /* LIBC_SCCS and not lint */ 36#include <sys/cdefs.h> 37__FBSDID("$FreeBSD: src/lib/libc/gen/getcap.c,v 1.23 2009/11/25 04:45:45 wollman Exp $"); 38 39#include "xlocale_private.h" 40 41#include "namespace.h" 42#include <sys/types.h> 43 44#include <ctype.h> 45#include <errno.h> 46#include <fcntl.h> 47#include <limits.h> 48#include <stdio.h> 49#include <stdlib.h> 50#include <string.h> 51#include <unistd.h> 52#include "un-namespace.h" 53 54#include <db.h> 55 56#define BFRAG 1024 57#define BSIZE 1024 58#define ESC ('[' & 037) /* ASCII ESC */ 59#define MAX_RECURSION 32 /* maximum getent recursion */ 60#define SFRAG 100 /* cgetstr mallocs in SFRAG chunks */ 61 62#define RECOK (char)0 63#define TCERR (char)1 64#define SHADOW (char)2 65 66static size_t topreclen; /* toprec length */ 67static char *toprec; /* Additional record specified by cgetset() */ 68static int gottoprec; /* Flag indicating retrieval of toprecord */ 69 70static int cdbget(DB *, char **, const char *); 71static int getent(char **, u_int *, char **, int, const char *, int, char *, locale_t); 72static int nfcmp(char *, char *); 73 74/* 75 * Cgetset() allows the addition of a user specified buffer to be added 76 * to the database array, in effect "pushing" the buffer on top of the 77 * virtual database. 0 is returned on success, -1 on failure. 78 */ 79int 80cgetset(const char *ent) 81{ 82 if (ent == NULL) { 83 if (toprec) 84 free(toprec); 85 toprec = NULL; 86 topreclen = 0; 87 return (0); 88 } 89 topreclen = strlen(ent); 90 if ((toprec = malloc (topreclen + 1)) == NULL) { 91 errno = ENOMEM; 92 return (-1); 93 } 94 gottoprec = 0; 95 (void)strcpy(toprec, ent); 96 return (0); 97} 98 99/* 100 * Cgetcap searches the capability record buf for the capability cap with 101 * type `type'. A pointer to the value of cap is returned on success, NULL 102 * if the requested capability couldn't be found. 103 * 104 * Specifying a type of ':' means that nothing should follow cap (:cap:). 105 * In this case a pointer to the terminating ':' or NUL will be returned if 106 * cap is found. 107 * 108 * If (cap, '@') or (cap, terminator, '@') is found before (cap, terminator) 109 * return NULL. 110 */ 111char * 112cgetcap(char *buf, const char *cap, int type) 113{ 114 char *bp; 115 const char *cp; 116 117 bp = buf; 118 for (;;) { 119 /* 120 * Skip past the current capability field - it's either the 121 * name field if this is the first time through the loop, or 122 * the remainder of a field whose name failed to match cap. 123 */ 124 for (;;) 125 if (*bp == '\0') 126 return (NULL); 127 else 128 if (*bp++ == ':') 129 break; 130 131 /* 132 * Try to match (cap, type) in buf. 133 */ 134 for (cp = cap; *cp == *bp && *bp != '\0'; cp++, bp++) 135 continue; 136 if (*cp != '\0') 137 continue; 138 if (*bp == '@') 139 return (NULL); 140 if (type == ':') { 141 if (*bp != '\0' && *bp != ':') 142 continue; 143 return(bp); 144 } 145 if (*bp != type) 146 continue; 147 bp++; 148 return (*bp == '@' ? NULL : bp); 149 } 150 /* NOTREACHED */ 151} 152 153/* 154 * Cgetent extracts the capability record name from the NULL terminated file 155 * array db_array and returns a pointer to a malloc'd copy of it in buf. 156 * Buf must be retained through all subsequent calls to cgetcap, cgetnum, 157 * cgetflag, and cgetstr, but may then be free'd. 0 is returned on success, 158 * -1 if the requested record couldn't be found, -2 if a system error was 159 * encountered (couldn't open/read a file, etc.), and -3 if a potential 160 * reference loop is detected. 161 */ 162int 163cgetent(char **buf, char **db_array, const char *name) 164{ 165 u_int dummy; 166 167 return (getent(buf, &dummy, db_array, -1, name, 0, NULL, __current_locale())); 168} 169 170/* 171 * Getent implements the functions of cgetent. If fd is non-negative, 172 * *db_array has already been opened and fd is the open file descriptor. We 173 * do this to save time and avoid using up file descriptors for tc= 174 * recursions. 175 * 176 * Getent returns the same success/failure codes as cgetent. On success, a 177 * pointer to a malloc'ed capability record with all tc= capabilities fully 178 * expanded and its length (not including trailing ASCII NUL) are left in 179 * *cap and *len. 180 * 181 * Basic algorithm: 182 * + Allocate memory incrementally as needed in chunks of size BFRAG 183 * for capability buffer. 184 * + Recurse for each tc=name and interpolate result. Stop when all 185 * names interpolated, a name can't be found, or depth exceeds 186 * MAX_RECURSION. 187 */ 188static int 189getent(char **cap, u_int *len, char **db_array, int fd, const char *name, 190 int depth, char *nfield, locale_t loc) 191{ 192 DB *capdbp; 193 char *r_end, *rp, **db_p; 194 int myfd, eof, foundit, retval; 195 char *record, *cbuf; 196 int tc_not_resolved; 197 char pbuf[_POSIX_PATH_MAX]; 198 199 /* 200 * Return with ``loop detected'' error if we've recursed more than 201 * MAX_RECURSION times. 202 */ 203 if (depth > MAX_RECURSION) 204 return (-3); 205 206 /* 207 * Check if we have a top record from cgetset(). 208 */ 209 if (depth == 0 && toprec != NULL && cgetmatch(toprec, name) == 0) { 210 if ((record = malloc (topreclen + BFRAG)) == NULL) { 211 errno = ENOMEM; 212 return (-2); 213 } 214 (void)strcpy(record, toprec); 215 myfd = 0; 216 db_p = db_array; 217 rp = record + topreclen + 1; 218 r_end = rp + BFRAG; 219 goto tc_exp; 220 } 221 /* 222 * Allocate first chunk of memory. 223 */ 224 if ((record = malloc(BFRAG)) == NULL) { 225 errno = ENOMEM; 226 return (-2); 227 } 228 r_end = record + BFRAG; 229 foundit = 0; 230 /* 231 * Loop through database array until finding the record. 232 */ 233 234 for (db_p = db_array; *db_p != NULL; db_p++) { 235 eof = 0; 236 237 /* 238 * Open database if not already open. 239 */ 240 241 if (fd >= 0) { 242 (void)lseek(fd, (off_t)0, SEEK_SET); 243 myfd = 0; 244 } else { 245 (void)snprintf(pbuf, sizeof(pbuf), "%s.db", *db_p); 246 if ((capdbp = dbopen(pbuf, O_RDONLY, 0, DB_HASH, 0)) 247 != NULL) { 248 free(record); 249 retval = cdbget(capdbp, &record, name); 250 if (retval < 0) { 251 /* no record available */ 252 (void)capdbp->close(capdbp); 253 return (retval); 254 } 255 /* save the data; close frees it */ 256 cbuf = strdup(record); 257 if (capdbp->close(capdbp) < 0) { 258 free(cbuf); 259 return (-2); 260 } 261 if (cbuf == NULL) { 262 errno = ENOMEM; 263 return (-2); 264 } 265 *len = strlen(cbuf); 266 *cap = cbuf; 267 return (retval); 268 } else { 269 fd = _open(*db_p, O_RDONLY, 0); 270 if (fd < 0) 271 continue; 272 myfd = 1; 273 } 274 } 275 /* 276 * Find the requested capability record ... 277 */ 278 { 279 char buf[BUFSIZ]; 280 char *b_end, *bp; 281 int c; 282 283 /* 284 * Loop invariants: 285 * There is always room for one more character in record. 286 * R_end always points just past end of record. 287 * Rp always points just past last character in record. 288 * B_end always points just past last character in buf. 289 * Bp always points at next character in buf. 290 */ 291 b_end = buf; 292 bp = buf; 293 for (;;) { 294 295 /* 296 * Read in a line implementing (\, newline) 297 * line continuation. 298 */ 299 rp = record; 300 for (;;) { 301 if (bp >= b_end) { 302 int n; 303 304 n = _read(fd, buf, sizeof(buf)); 305 if (n <= 0) { 306 if (myfd) 307 (void)_close(fd); 308 if (n < 0) { 309 free(record); 310 return (-2); 311 } else { 312 fd = -1; 313 eof = 1; 314 break; 315 } 316 } 317 b_end = buf+n; 318 bp = buf; 319 } 320 321 c = *bp++; 322 if (c == '\n') { 323 if (rp > record && *(rp-1) == '\\') { 324 rp--; 325 continue; 326 } else 327 break; 328 } 329 *rp++ = c; 330 331 /* 332 * Enforce loop invariant: if no room 333 * left in record buffer, try to get 334 * some more. 335 */ 336 if (rp >= r_end) { 337 u_int pos; 338 size_t newsize; 339 340 pos = rp - record; 341 newsize = r_end - record + BFRAG; 342 record = reallocf(record, newsize); 343 if (record == NULL) { 344 errno = ENOMEM; 345 if (myfd) 346 (void)_close(fd); 347 return (-2); 348 } 349 r_end = record + newsize; 350 rp = record + pos; 351 } 352 } 353 /* loop invariant let's us do this */ 354 *rp++ = '\0'; 355 356 /* 357 * If encountered eof check next file. 358 */ 359 if (eof) 360 break; 361 362 /* 363 * Toss blank lines and comments. 364 */ 365 if (*record == '\0' || *record == '#') 366 continue; 367 368 /* 369 * See if this is the record we want ... 370 */ 371 if (cgetmatch(record, name) == 0) { 372 if (nfield == NULL || !nfcmp(nfield, record)) { 373 foundit = 1; 374 break; /* found it! */ 375 } 376 } 377 } 378 } 379 if (foundit) 380 break; 381 } 382 383 if (!foundit) { 384 free(record); 385 return (-1); 386 } 387 388 /* 389 * Got the capability record, but now we have to expand all tc=name 390 * references in it ... 391 */ 392tc_exp: { 393 char *newicap, *s; 394 int newilen; 395 u_int ilen; 396 int diff, iret, tclen; 397 char *icap, *scan, *tc, *tcstart, *tcend; 398 399 /* 400 * Loop invariants: 401 * There is room for one more character in record. 402 * R_end points just past end of record. 403 * Rp points just past last character in record. 404 * Scan points at remainder of record that needs to be 405 * scanned for tc=name constructs. 406 */ 407 scan = record; 408 tc_not_resolved = 0; 409 for (;;) { 410 if ((tc = cgetcap(scan, "tc", '=')) == NULL) 411 break; 412 413 /* 414 * Find end of tc=name and stomp on the trailing `:' 415 * (if present) so we can use it to call ourselves. 416 */ 417 s = tc; 418 for (;;) 419 if (*s == '\0') 420 break; 421 else 422 if (*s++ == ':') { 423 *(s - 1) = '\0'; 424 break; 425 } 426 tcstart = tc - 3; 427 tclen = s - tcstart; 428 tcend = s; 429 430 iret = getent(&icap, &ilen, db_p, fd, tc, depth+1, 431 NULL, loc); 432 newicap = icap; /* Put into a register. */ 433 newilen = ilen; 434 if (iret != 0) { 435 /* an error */ 436 if (iret < -1) { 437 if (myfd) 438 (void)_close(fd); 439 free(record); 440 return (iret); 441 } 442 if (iret == 1) 443 tc_not_resolved = 1; 444 /* couldn't resolve tc */ 445 if (iret == -1) { 446 *(s - 1) = ':'; 447 scan = s - 1; 448 tc_not_resolved = 1; 449 continue; 450 451 } 452 } 453 /* not interested in name field of tc'ed record */ 454 s = newicap; 455 for (;;) 456 if (*s == '\0') 457 break; 458 else 459 if (*s++ == ':') 460 break; 461 newilen -= s - newicap; 462 newicap = s; 463 464 /* make sure interpolated record is `:'-terminated */ 465 s += newilen; 466 if (*(s-1) != ':') { 467 *s = ':'; /* overwrite NUL with : */ 468 newilen++; 469 } 470 471 /* 472 * Make sure there's enough room to insert the 473 * new record. 474 */ 475 diff = newilen - tclen; 476 if (diff >= r_end - rp) { 477 u_int pos, tcpos, tcposend; 478 size_t newsize; 479 480 pos = rp - record; 481 newsize = r_end - record + diff + BFRAG; 482 tcpos = tcstart - record; 483 tcposend = tcend - record; 484 record = reallocf(record, newsize); 485 if (record == NULL) { 486 errno = ENOMEM; 487 if (myfd) 488 (void)_close(fd); 489 free(icap); 490 return (-2); 491 } 492 r_end = record + newsize; 493 rp = record + pos; 494 tcstart = record + tcpos; 495 tcend = record + tcposend; 496 } 497 498 /* 499 * Insert tc'ed record into our record. 500 */ 501 s = tcstart + newilen; 502 bcopy(tcend, s, rp - tcend); 503 bcopy(newicap, tcstart, newilen); 504 rp += diff; 505 free(icap); 506 507 /* 508 * Start scan on `:' so next cgetcap works properly 509 * (cgetcap always skips first field). 510 */ 511 scan = s-1; 512 } 513 514 } 515 /* 516 * Close file (if we opened it), give back any extra memory, and 517 * return capability, length and success. 518 */ 519 if (myfd) 520 (void)_close(fd); 521 *len = rp - record - 1; /* don't count NUL */ 522 if (r_end > rp) 523 if ((record = 524 reallocf(record, (size_t)(rp - record))) == NULL) { 525 errno = ENOMEM; 526 return (-2); 527 } 528 529 *cap = record; 530 if (tc_not_resolved) 531 return (1); 532 return (0); 533} 534 535static int 536cdbget(DB *capdbp, char **bp, const char *name) 537{ 538 DBT key, data; 539 char *namebuf; 540 541 namebuf = strdup(name); 542 if (namebuf == NULL) 543 return (-2); 544 key.data = namebuf; 545 key.size = strlen(namebuf); 546 547 for (;;) { 548 /* Get the reference. */ 549 switch(capdbp->get(capdbp, &key, &data, 0)) { 550 case -1: 551 free(namebuf); 552 return (-2); 553 case 1: 554 free(namebuf); 555 return (-1); 556 } 557 558 /* If not an index to another record, leave. */ 559 if (((char *)data.data)[0] != SHADOW) 560 break; 561 562 key.data = (char *)data.data + 1; 563 key.size = data.size - 1; 564 } 565 566 *bp = (char *)data.data + 1; 567 free(namebuf); 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 */ 575int 576cgetmatch(const char *buf, const char *name) 577{ 578 const char *np, *bp; 579 580 if (name == NULL || *name == '\0') 581 return -1; 582 583 /* 584 * Start search at beginning of record. 585 */ 586 bp = buf; 587 for (;;) { 588 /* 589 * Try to match a record name. 590 */ 591 np = name; 592 for (;;) 593 if (*np == '\0') 594 if (*bp == '|' || *bp == ':' || *bp == '\0') 595 return (0); 596 else 597 break; 598 else 599 if (*bp++ != *np++) 600 break; 601 602 /* 603 * Match failed, skip to next name in record. 604 */ 605 bp--; /* a '|' or ':' may have stopped the match */ 606 for (;;) 607 if (*bp == '\0' || *bp == ':') 608 return (-1); /* match failed totally */ 609 else 610 if (*bp++ == '|') 611 break; /* found next name */ 612 } 613} 614 615 616 617 618 619int 620cgetfirst(char **buf, char **db_array) 621{ 622 (void)cgetclose(); 623 return (cgetnext(buf, db_array)); 624} 625 626static FILE *pfp; 627static int slash; 628static char **dbp; 629 630int 631cgetclose(void) 632{ 633 if (pfp != NULL) { 634 (void)fclose(pfp); 635 pfp = NULL; 636 } 637 dbp = NULL; 638 gottoprec = 0; 639 slash = 0; 640 return(0); 641} 642 643/* 644 * Cgetnext() gets either the first or next entry in the logical database 645 * specified by db_array. It returns 0 upon completion of the database, 1 646 * upon returning an entry with more remaining, and -1 if an error occurs. 647 */ 648int 649cgetnext(char **bp, char **db_array) 650{ 651 size_t len; 652 int done, hadreaderr, savederrno, status; 653 char *cp, *line, *rp, *np, buf[BSIZE], nbuf[BSIZE]; 654 u_int dummy; 655 locale_t loc = __current_locale(); 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_l((unsigned char)*line, loc) || 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 done = 0; 716 np = nbuf; 717 for (;;) { 718 for (cp = line; *cp != '\0'; cp++) { 719 if (*cp == ':') { 720 *np++ = ':'; 721 done = 1; 722 break; 723 } 724 if (*cp == '\\') 725 break; 726 *np++ = *cp; 727 } 728 if (done) { 729 *np = '\0'; 730 break; 731 } else { /* name field extends beyond the line */ 732 line = fgetln(pfp, &len); 733 if (line == NULL && pfp) { 734 /* Name extends beyond the EOF! */ 735 hadreaderr = ferror(pfp); 736 if (hadreaderr) 737 savederrno = errno; 738 fclose(pfp); 739 pfp = NULL; 740 if (hadreaderr) { 741 cgetclose(); 742 errno = savederrno; 743 return (-1); 744 } else { 745 cgetclose(); 746 return (-1); 747 } 748 } else 749 line[len - 1] = '\0'; 750 } 751 } 752 rp = buf; 753 for(cp = nbuf; *cp != '\0'; cp++) 754 if (*cp == '|' || *cp == ':') 755 break; 756 else 757 *rp++ = *cp; 758 759 *rp = '\0'; 760 /* 761 * XXX 762 * Last argument of getent here should be nbuf if we want true 763 * sequential access in the case of duplicates. 764 * With NULL, getent will return the first entry found 765 * rather than the duplicate entry record. This is a 766 * matter of semantics that should be resolved. 767 */ 768 status = getent(bp, &dummy, db_array, -1, buf, 0, NULL, loc); 769 if (status == -2 || status == -3) 770 (void)cgetclose(); 771 772 return (status + 1); 773 } 774 /* NOTREACHED */ 775} 776 777/* 778 * Cgetstr retrieves the value of the string capability cap from the 779 * capability record pointed to by buf. A pointer to a decoded, NUL 780 * terminated, malloc'd copy of the string is returned in the char * 781 * pointed to by str. The length of the string not including the trailing 782 * NUL is returned on success, -1 if the requested string capability 783 * couldn't be found, -2 if a system error was encountered (storage 784 * allocation failure). 785 */ 786int 787cgetstr(char *buf, const char *cap, char **str) 788{ 789 u_int m_room; 790 char *bp, *mp; 791 int len; 792 char *mem; 793 794 /* 795 * Find string capability cap 796 */ 797 bp = cgetcap(buf, cap, '='); 798 if (bp == NULL) 799 return (-1); 800 801 /* 802 * Conversion / storage allocation loop ... Allocate memory in 803 * chunks SFRAG in size. 804 */ 805 if ((mem = malloc(SFRAG)) == NULL) { 806 errno = ENOMEM; 807 return (-2); /* couldn't even allocate the first fragment */ 808 } 809 m_room = SFRAG; 810 mp = mem; 811 812 while (*bp != ':' && *bp != '\0') { 813 /* 814 * Loop invariants: 815 * There is always room for one more character in mem. 816 * Mp always points just past last character in mem. 817 * Bp always points at next character in buf. 818 */ 819 if (*bp == '^') { 820 bp++; 821 if (*bp == ':' || *bp == '\0') 822 break; /* drop unfinished escape */ 823 if (*bp == '?') { 824 *mp++ = '\177'; 825 bp++; 826 } else 827 *mp++ = *bp++ & 037; 828 } else if (*bp == '\\') { 829 bp++; 830 if (*bp == ':' || *bp == '\0') 831 break; /* drop unfinished escape */ 832 if ('0' <= *bp && *bp <= '7') { 833 int n, i; 834 835 n = 0; 836 i = 3; /* maximum of three octal digits */ 837 do { 838 n = n * 8 + (*bp++ - '0'); 839 } while (--i && '0' <= *bp && *bp <= '7'); 840 *mp++ = n; 841 } 842 else switch (*bp++) { 843 case 'b': case 'B': 844 *mp++ = '\b'; 845 break; 846 case 't': case 'T': 847 *mp++ = '\t'; 848 break; 849 case 'n': case 'N': 850 *mp++ = '\n'; 851 break; 852 case 'f': case 'F': 853 *mp++ = '\f'; 854 break; 855 case 'r': case 'R': 856 *mp++ = '\r'; 857 break; 858 case 'e': case 'E': 859 *mp++ = ESC; 860 break; 861 case 'c': case 'C': 862 *mp++ = ':'; 863 break; 864 default: 865 /* 866 * Catches '\', '^', and 867 * everything else. 868 */ 869 *mp++ = *(bp-1); 870 break; 871 } 872 } else 873 *mp++ = *bp++; 874 m_room--; 875 876 /* 877 * Enforce loop invariant: if no room left in current 878 * buffer, try to get some more. 879 */ 880 if (m_room == 0) { 881 size_t size = mp - mem; 882 883 if ((mem = reallocf(mem, size + SFRAG)) == NULL) 884 return (-2); 885 m_room = SFRAG; 886 mp = mem + size; 887 } 888 } 889 *mp++ = '\0'; /* loop invariant let's us do this */ 890 m_room--; 891 len = mp - mem - 1; 892 893 /* 894 * Give back any extra memory and return value and success. 895 */ 896 if (m_room != 0) 897 if ((mem = reallocf(mem, (size_t)(mp - mem))) == NULL) 898 return (-2); 899 *str = mem; 900 return (len); 901} 902 903/* 904 * Cgetustr retrieves the value of the string capability cap from the 905 * capability record pointed to by buf. The difference between cgetustr() 906 * and cgetstr() is that cgetustr does not decode escapes but rather treats 907 * all characters literally. A pointer to a NUL terminated malloc'd 908 * copy of the string is returned in the char pointed to by str. The 909 * length of the string not including the trailing NUL is returned on success, 910 * -1 if the requested string capability couldn't be found, -2 if a system 911 * error was encountered (storage allocation failure). 912 */ 913int 914cgetustr(char *buf, const char *cap, char **str) 915{ 916 u_int m_room; 917 char *bp, *mp; 918 int len; 919 char *mem; 920 921 /* 922 * Find string capability cap 923 */ 924 if ((bp = cgetcap(buf, cap, '=')) == NULL) 925 return (-1); 926 927 /* 928 * Conversion / storage allocation loop ... Allocate memory in 929 * chunks SFRAG in size. 930 */ 931 if ((mem = malloc(SFRAG)) == NULL) { 932 errno = ENOMEM; 933 return (-2); /* couldn't even allocate the first fragment */ 934 } 935 m_room = SFRAG; 936 mp = mem; 937 938 while (*bp != ':' && *bp != '\0') { 939 /* 940 * Loop invariants: 941 * There is always room for one more character in mem. 942 * Mp always points just past last character in mem. 943 * Bp always points at next character in buf. 944 */ 945 *mp++ = *bp++; 946 m_room--; 947 948 /* 949 * Enforce loop invariant: if no room left in current 950 * buffer, try to get some more. 951 */ 952 if (m_room == 0) { 953 size_t size = mp - mem; 954 955 if ((mem = reallocf(mem, size + SFRAG)) == NULL) 956 return (-2); 957 m_room = SFRAG; 958 mp = mem + size; 959 } 960 } 961 *mp++ = '\0'; /* loop invariant let's us do this */ 962 m_room--; 963 len = mp - mem - 1; 964 965 /* 966 * Give back any extra memory and return value and success. 967 */ 968 if (m_room != 0) 969 if ((mem = reallocf(mem, (size_t)(mp - mem))) == NULL) 970 return (-2); 971 *str = mem; 972 return (len); 973} 974 975/* 976 * Cgetnum retrieves the value of the numeric capability cap from the 977 * capability record pointed to by buf. The numeric value is returned in 978 * the long pointed to by num. 0 is returned on success, -1 if the requested 979 * numeric capability couldn't be found. 980 */ 981int 982cgetnum(char *buf, const char *cap, long *num) 983{ 984 long n; 985 int base, digit; 986 char *bp; 987 988 /* 989 * Find numeric capability cap 990 */ 991 bp = cgetcap(buf, cap, '#'); 992 if (bp == NULL) 993 return (-1); 994 995 /* 996 * Look at value and determine numeric base: 997 * 0x... or 0X... hexadecimal, 998 * else 0... octal, 999 * else decimal. 1000 */ 1001 if (*bp == '0') { 1002 bp++; 1003 if (*bp == 'x' || *bp == 'X') { 1004 bp++; 1005 base = 16; 1006 } else 1007 base = 8; 1008 } else 1009 base = 10; 1010 1011 /* 1012 * Conversion loop ... 1013 */ 1014 n = 0; 1015 for (;;) { 1016 if ('0' <= *bp && *bp <= '9') 1017 digit = *bp - '0'; 1018 else if ('a' <= *bp && *bp <= 'f') 1019 digit = 10 + *bp - 'a'; 1020 else if ('A' <= *bp && *bp <= 'F') 1021 digit = 10 + *bp - 'A'; 1022 else 1023 break; 1024 1025 if (digit >= base) 1026 break; 1027 1028 n = n * base + digit; 1029 bp++; 1030 } 1031 1032 /* 1033 * Return value and success. 1034 */ 1035 *num = n; 1036 return (0); 1037} 1038 1039 1040/* 1041 * Compare name field of record. 1042 */ 1043static int 1044nfcmp(char *nf, char *rec) 1045{ 1046 char *cp, tmp; 1047 int ret; 1048 1049 for (cp = rec; *cp != ':'; cp++) 1050 ; 1051 1052 tmp = *(cp + 1); 1053 *(cp + 1) = '\0'; 1054 ret = strcmp(nf, rec); 1055 *(cp + 1) = tmp; 1056 1057 return (ret); 1058} 1059