1 /* $NetBSD: getcap.c,v 1.56 2014/09/24 13:18:52 christos 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. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 #if HAVE_NBTOOL_CONFIG_H
36 #include "nbtool_config.h"
37 #endif
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 1.56 2014/09/24 13:18:52 christos Exp $");
45 #endif
46 #endif /* LIBC_SCCS and not lint */
47
48 #ifndef SMALL
49 #include "namespace.h"
50 #endif
51 #include <sys/types.h>
52 #include <sys/param.h>
53
54 #include <assert.h>
55 #include <stddef.h>
56 #include <ctype.h>
57 #ifndef SMALL
58 #include <db.h>
59 #endif
60 #include <errno.h>
61 #include <fcntl.h>
62 #include <limits.h>
63 #include <stdio.h>
64 #include <stdlib.h>
65 #include <string.h>
66 #include <unistd.h>
67
68 #if defined(__weak_alias) && !defined(SMALL)
69 __weak_alias(cgetcap,_cgetcap)
70 __weak_alias(cgetclose,_cgetclose)
71 __weak_alias(cgetent,_cgetent)
72 __weak_alias(cgetfirst,_cgetfirst)
73 __weak_alias(cgetmatch,_cgetmatch)
74 __weak_alias(cgetnext,_cgetnext)
75 __weak_alias(cgetnum,_cgetnum)
76 __weak_alias(cgetset,_cgetset)
77 __weak_alias(cgetstr,_cgetstr)
78 __weak_alias(cgetustr,_cgetustr)
79 __weak_alias(csetexpandtc,_csetexpandtc)
80 #endif
81
82 #define BFRAG 1024
83 #define BSIZE 1024
84 #define ESC ('[' & 037) /* ASCII ESC */
85 #define MAX_RECURSION 32 /* maximum getent recursion */
86 #define SFRAG 100 /* cgetstr mallocs in SFRAG chunks */
87
88 #define RECOK (char)0
89 #define TCERR (char)1
90 #define SHADOW (char)2
91
92 static size_t topreclen; /* toprec length */
93 static char *toprec; /* Additional record specified by cgetset() */
94 static int gottoprec; /* Flag indicating retrieval of toprecord */
95 static int expandtc = 1; /* flag to expand tc= or not */
96
97 #ifndef SMALL
98 static int cdbget(DB *, char **, const char *);
99 #endif
100 static int getent(char **, size_t *, const char * const *, int,
101 const char *, int, char *);
102 static int nfcmp(char *, char *);
103
104 /*
105 * Cgetset() allows the addition of a user specified buffer to be added
106 * to the database array, in effect "pushing" the buffer on top of the
107 * virtual database. 0 is returned on success, -1 on failure.
108 */
109 int
cgetset(const char * ent)110 cgetset(const char *ent)
111 {
112 const char *source, *check;
113 char *dest;
114
115 if (ent == NULL) {
116 if (toprec != NULL)
117 free(toprec);
118 toprec = NULL;
119 topreclen = 0;
120 return 0;
121 }
122 topreclen = strlen(ent);
123 if ((toprec = malloc(topreclen + 1)) == NULL) {
124 errno = ENOMEM;
125 return -1;
126 }
127 gottoprec = 0;
128
129 source = ent;
130 dest = toprec;
131 while (*source != '\0') { /* Strip whitespace */
132 *dest++ = *source++; /* Do not check first field */
133 while (*source == ':') {
134 check = source + 1;
135 while (*check && (isspace((unsigned char)*check) ||
136 (*check=='\\' && isspace((unsigned char)check[1]))))
137 ++check;
138 if (*check == ':')
139 source = check;
140 else
141 break;
142
143 }
144 }
145 *dest = 0;
146
147 return 0;
148 }
149
150 /*
151 * Cgetcap searches the capability record buf for the capability cap with
152 * type `type'. A pointer to the value of cap is returned on success, NULL
153 * if the requested capability couldn't be found.
154 *
155 * Specifying a type of ':' means that nothing should follow cap (:cap:).
156 * In this case a pointer to the terminating ':' or NUL will be returned if
157 * cap is found.
158 *
159 * If (cap, '@') or (cap, terminator, '@') is found before (cap, terminator)
160 * return NULL.
161 */
162 char *
cgetcap(char * buf,const char * cap,int type)163 cgetcap(char *buf, const char *cap, int type)
164 {
165 char *bp;
166 const char *cp;
167
168 _DIAGASSERT(buf != NULL);
169 _DIAGASSERT(cap != NULL);
170
171 bp = buf;
172 for (;;) {
173 /*
174 * Skip past the current capability field - it's either the
175 * name field if this is the first time through the loop, or
176 * the remainder of a field whose name failed to match cap.
177 */
178 for (;;)
179 if (*bp == '\0')
180 return NULL;
181 else if (*bp++ == ':')
182 break;
183
184 /*
185 * Try to match (cap, type) in buf.
186 */
187 for (cp = cap; *cp == *bp && *bp != '\0'; cp++, bp++)
188 continue;
189 if (*cp != '\0')
190 continue;
191 if (*bp == '@')
192 return NULL;
193 if (type == ':') {
194 if (*bp != '\0' && *bp != ':')
195 continue;
196 return bp;
197 }
198 if (*bp != type)
199 continue;
200 bp++;
201 return *bp == '@' ? NULL : bp;
202 }
203 /* NOTREACHED */
204 }
205
206 /*
207 * Cgetent extracts the capability record name from the NULL terminated file
208 * array db_array and returns a pointer to a malloc'd copy of it in buf.
209 * Buf must be retained through all subsequent calls to cgetcap, cgetnum,
210 * cgetflag, and cgetstr, but may then be free'd. 0 is returned on success,
211 * -1 if the requested record couldn't be found, -2 if a system error was
212 * encountered (couldn't open/read a file, etc.), and -3 if a potential
213 * reference loop is detected.
214 */
215 /* coverity[+alloc : arg-*0] */
216 int
cgetent(char ** buf,const char * const * db_array,const char * name)217 cgetent(char **buf, const char * const *db_array, const char *name)
218 {
219 size_t dummy;
220
221 _DIAGASSERT(buf != NULL);
222 _DIAGASSERT(db_array != NULL);
223 _DIAGASSERT(name != NULL);
224
225 return getent(buf, &dummy, db_array, -1, name, 0, NULL);
226 }
227
228 void
csetexpandtc(int etc)229 csetexpandtc(int etc)
230 {
231 expandtc = etc;
232 }
233
234 /*
235 * Getent implements the functions of cgetent. If fd is non-negative,
236 * *db_array has already been opened and fd is the open file descriptor. We
237 * do this to save time and avoid using up file descriptors for tc=
238 * recursions.
239 *
240 * Getent returns the same success/failure codes as cgetent. On success, a
241 * pointer to a malloc'ed capability record with all tc= capabilities fully
242 * expanded and its length (not including trailing ASCII NUL) are left in
243 * *cap and *len.
244 *
245 * Basic algorithm:
246 * + Allocate memory incrementally as needed in chunks of size BFRAG
247 * for capability buffer.
248 * + Recurse for each tc=name and interpolate result. Stop when all
249 * names interpolated, a name can't be found, or depth exceeds
250 * MAX_RECURSION.
251 */
252 /* coverity[+alloc : arg-*0] */
253 static int
getent(char ** cap,size_t * len,const char * const * db_array,int fd,const char * name,int depth,char * nfield)254 getent(char **cap, size_t *len, const char * const *db_array, int fd,
255 const char *name, int depth, char *nfield)
256 {
257 char *record, *newrecord;
258 char *r_end, *rp; /* pacify gcc */
259 const char * const *db_p;
260 int myfd, eof, foundit;
261 int tc_not_resolved;
262
263 _DIAGASSERT(cap != NULL);
264 _DIAGASSERT(len != NULL);
265 _DIAGASSERT(db_array != NULL);
266 /* fd may be -1 */
267 _DIAGASSERT(name != NULL);
268 /* nfield may be NULL */
269
270 myfd = 0;
271 rp = NULL;
272
273 /*
274 * Return with ``loop detected'' error if we've recursed more than
275 * MAX_RECURSION times.
276 */
277 if (depth > MAX_RECURSION)
278 return -3;
279
280 /*
281 * Check if we have a top record from cgetset().
282 */
283 if (depth == 0 && toprec != NULL && cgetmatch(toprec, name) == 0) {
284 if ((record = malloc(topreclen + BFRAG)) == NULL) {
285 errno = ENOMEM;
286 return -2;
287 }
288 (void)strcpy(record, toprec); /* XXX: strcpy is safe */
289 db_p = db_array;
290 rp = record + topreclen + 1;
291 r_end = rp + BFRAG;
292 goto tc_exp;
293 }
294 /*
295 * Allocate first chunk of memory.
296 */
297 if ((record = malloc(BFRAG)) == NULL) {
298 errno = ENOMEM;
299 return -2;
300 }
301 r_end = record + BFRAG;
302 foundit = 0;
303 /*
304 * Loop through database array until finding the record.
305 */
306
307 for (db_p = db_array; *db_p != NULL; db_p++) {
308 eof = 0;
309
310 /*
311 * Open database if not already open.
312 */
313
314 if (fd >= 0) {
315 (void)lseek(fd, (off_t)0, SEEK_SET);
316 } else {
317 #ifndef SMALL
318 DB *capdbp;
319 char pbuf[MAXPATHLEN];
320 char *cbuf;
321 int retval;
322 size_t clen;
323
324 (void)snprintf(pbuf, sizeof(pbuf), "%s.db", *db_p);
325 if ((capdbp = dbopen(pbuf, O_RDONLY | O_CLOEXEC, 0,
326 DB_HASH, 0)) != NULL) {
327 free(record);
328 retval = cdbget(capdbp, &record, name);
329 if (retval < 0) {
330 /* no record available */
331 (void)capdbp->close(capdbp);
332 return retval;
333 }
334 /* save the data; close frees it */
335 clen = strlen(record);
336 if ((cbuf = malloc(clen + 1)) == NULL) {
337 (void)capdbp->close(capdbp);
338 errno = ENOMEM;
339 return -2;
340 }
341 memmove(cbuf, record, clen + 1);
342 if (capdbp->close(capdbp) < 0) {
343 int serrno = errno;
344
345 free(cbuf);
346 errno = serrno;
347 return -2;
348 }
349 *len = clen;
350 *cap = cbuf;
351 return retval;
352 } else
353 #endif
354 {
355 fd = open(*db_p, O_RDONLY | O_CLOEXEC, 0);
356 if (fd < 0) {
357 /* No error on unfound file. */
358 continue;
359 }
360 myfd = 1;
361 }
362 }
363 /*
364 * Find the requested capability record ...
365 */
366 {
367 char buf[BUFSIZ];
368 char *b_end, *bp, *cp;
369 int c, slash;
370
371 /*
372 * Loop invariants:
373 * There is always room for one more character in record.
374 * R_end always points just past end of record.
375 * Rp always points just past last character in record.
376 * B_end always points just past last character in buf.
377 * Bp always points at next character in buf.
378 * Cp remembers where the last colon was.
379 */
380 b_end = buf;
381 bp = buf;
382 cp = NULL;
383 slash = 0;
384 for (;;) {
385 /*
386 * Read in a line implementing (\, newline)
387 * line continuation.
388 */
389 rp = record;
390 for (;;) {
391 if (bp >= b_end) {
392 ssize_t n;
393
394 n = read(fd, buf, sizeof(buf));
395 if (n <= 0) {
396 if (myfd)
397 (void)close(fd);
398 if (n < 0) {
399 int serrno = errno;
400
401 free(record);
402 errno = serrno;
403 return -2;
404 } else {
405 fd = -1;
406 eof = 1;
407 break;
408 }
409 }
410 b_end = buf+n;
411 bp = buf;
412 }
413
414 c = *bp++;
415 if (c == '\n') {
416 if (slash) {
417 slash = 0;
418 rp--;
419 continue;
420 } else
421 break;
422 }
423 if (slash) {
424 slash = 0;
425 cp = 0;
426 }
427 if (c == ':') {
428 /*
429 * If the field was `empty' (i.e.
430 * contained only white space), back up
431 * to the colon (eliminating the
432 * field).
433 */
434 if (cp != NULL)
435 rp = cp;
436 else
437 cp = rp;
438 } else if (c == '\\') {
439 slash = 1;
440 } else if (c != ' ' && c != '\t') {
441 /*
442 * Forget where the colon was, as this
443 * is not an empty field.
444 */
445 cp = 0;
446 }
447 *rp++ = c;
448
449 /*
450 * Enforce loop invariant: if no room
451 * left in record buffer, try to get
452 * some more.
453 */
454 if (rp >= r_end) {
455 ptrdiff_t pos;
456 size_t newsize;
457
458 pos = rp - record;
459 newsize = r_end - record + BFRAG;
460 newrecord = realloc(record, newsize);
461 if (newrecord == NULL) {
462 free(record);
463 if (myfd)
464 (void)close(fd);
465 errno = ENOMEM;
466 return -2;
467 }
468 record = newrecord;
469 r_end = record + newsize;
470 rp = record + pos;
471 }
472 }
473 /* Eliminate any white space after the last colon. */
474 if (cp)
475 rp = cp + 1;
476 /* Loop invariant lets us do this. */
477 *rp++ = '\0';
478
479 /*
480 * If encountered eof check next file.
481 */
482 if (eof)
483 break;
484
485 /*
486 * Toss blank lines and comments.
487 */
488 if (*record == '\0' || *record == '#')
489 continue;
490
491 /*
492 * See if this is the record we want ...
493 */
494 if (cgetmatch(record, name) == 0)
495 if (nfield == NULL || !nfcmp(nfield, record)) {
496 foundit = 1;
497 break; /* found it! */
498 }
499 }
500 }
501 if (foundit)
502 break;
503 }
504
505 if (!foundit)
506 return -1;
507
508 /*
509 * Got the capability record, but now we have to expand all tc=name
510 * references in it ...
511 */
512 tc_exp:
513 tc_not_resolved = 0;
514 if (expandtc) {
515 char *newicap, *s;
516 size_t ilen, newilen;
517 int iret;
518 ptrdiff_t diff, tclen;
519 char *icap, *scan, *tc, *tcstart, *tcend;
520
521 /*
522 * Loop invariants:
523 * There is room for one more character in record.
524 * R_end points just past end of record.
525 * Rp points just past last character in record.
526 * Scan points at remainder of record that needs to be
527 * scanned for tc=name constructs.
528 */
529 scan = record;
530 for (;;) {
531 if ((tc = cgetcap(scan, "tc", '=')) == NULL)
532 break;
533
534 /*
535 * Find end of tc=name and stomp on the trailing `:'
536 * (if present) so we can use it to call ourselves.
537 */
538 s = tc;
539 for (;;)
540 if (*s == '\0')
541 break;
542 else
543 if (*s++ == ':') {
544 *(s - 1) = '\0';
545 break;
546 }
547 tcstart = tc - 3;
548 tclen = s - tcstart;
549 tcend = s;
550
551 iret = getent(&icap, &ilen, db_p, fd, tc, depth+1,
552 NULL);
553 newicap = icap; /* Put into a register. */
554 newilen = ilen;
555 if (iret != 0) {
556 /* an error */
557 if (iret < -1) {
558 if (myfd)
559 (void)close(fd);
560 free(record);
561 return iret;
562 }
563 if (iret == 1)
564 tc_not_resolved = 1;
565 /* couldn't resolve tc */
566 if (iret == -1) {
567 *(s - 1) = ':';
568 scan = s - 1;
569 tc_not_resolved = 1;
570 continue;
571
572 }
573 }
574 /* not interested in name field of tc'ed record */
575 s = newicap;
576 for (;;)
577 if (*s == '\0')
578 break;
579 else if (*s++ == ':')
580 break;
581 newilen -= s - newicap;
582 newicap = s;
583
584 /* make sure interpolated record is `:'-terminated */
585 s += newilen;
586 if (*(s - 1) != ':') {
587 *s = ':'; /* overwrite NUL with : */
588 newilen++;
589 }
590
591 /*
592 * Make sure there's enough room to insert the
593 * new record.
594 */
595 diff = newilen - tclen;
596 if (diff >= r_end - rp) {
597 ptrdiff_t pos, tcpos, tcposend;
598 size_t newsize;
599
600 pos = rp - record;
601 newsize = r_end - record + diff + BFRAG;
602 tcpos = tcstart - record;
603 tcposend = tcend - record;
604 newrecord = realloc(record, newsize);
605 if (newrecord == NULL) {
606 free(record);
607 if (myfd)
608 (void)close(fd);
609 free(icap);
610 errno = ENOMEM;
611 return -2;
612 }
613 record = newrecord;
614 r_end = record + newsize;
615 rp = record + pos;
616 tcstart = record + tcpos;
617 tcend = record + tcposend;
618 }
619
620 /*
621 * Insert tc'ed record into our record.
622 */
623 s = tcstart + newilen;
624 memmove(s, tcend, (size_t)(rp - tcend));
625 memmove(tcstart, newicap, newilen);
626 rp += diff;
627 free(icap);
628
629 /*
630 * Start scan on `:' so next cgetcap works properly
631 * (cgetcap always skips first field).
632 */
633 scan = s - 1;
634 }
635
636 }
637 /*
638 * Close file (if we opened it), give back any extra memory, and
639 * return capability, length and success.
640 */
641 if (myfd)
642 (void)close(fd);
643 *len = rp - record - 1; /* don't count NUL */
644 if (r_end > rp) {
645 if ((newrecord =
646 realloc(record, (size_t)(rp - record))) == NULL) {
647 free(record);
648 errno = ENOMEM;
649 return -2;
650 }
651 record = newrecord;
652 }
653
654 *cap = record;
655 if (tc_not_resolved)
656 return 1;
657 return 0;
658 }
659
660 #ifndef SMALL
661 static int
cdbget(DB * capdbp,char ** bp,const char * name)662 cdbget(DB *capdbp, char **bp, const char *name)
663 {
664 DBT key;
665 DBT data;
666
667 _DIAGASSERT(capdbp != NULL);
668 _DIAGASSERT(bp != NULL);
669 _DIAGASSERT(name != NULL);
670
671 key.data = __UNCONST(name);
672 key.size = strlen(name);
673
674 for (;;) {
675 /* Get the reference. */
676 switch(capdbp->get(capdbp, &key, &data, 0)) {
677 case -1:
678 return -2;
679 case 1:
680 return -1;
681 }
682
683 /* If not an index to another record, leave. */
684 if (((char *)data.data)[0] != SHADOW)
685 break;
686
687 key.data = (char *)data.data + 1;
688 key.size = data.size - 1;
689 }
690
691 *bp = (char *)data.data + 1;
692 return ((char *)(data.data))[0] == TCERR ? 1 : 0;
693 }
694 #endif
695
696 /*
697 * Cgetmatch will return 0 if name is one of the names of the capability
698 * record buf, -1 if not.
699 */
700 int
cgetmatch(const char * buf,const char * name)701 cgetmatch(const char *buf, const char *name)
702 {
703 const char *np, *bp;
704
705 _DIAGASSERT(buf != NULL);
706 _DIAGASSERT(name != NULL);
707
708 /*
709 * Start search at beginning of record.
710 */
711 bp = buf;
712 for (;;) {
713 /*
714 * Try to match a record name.
715 */
716 np = name;
717 for (;;)
718 if (*np == '\0') {
719 if (*bp == '|' || *bp == ':' || *bp == '\0')
720 return 0;
721 else
722 break;
723 } else if (*bp++ != *np++)
724 break;
725
726 /*
727 * Match failed, skip to next name in record.
728 */
729 if (bp > buf)
730 bp--; /* a '|' or ':' may have stopped the match */
731 else
732 return -1;
733 for (;;)
734 if (*bp == '\0' || *bp == ':')
735 return -1; /* match failed totally */
736 else if (*bp++ == '|')
737 break; /* found next name */
738 }
739 }
740
741 int
cgetfirst(char ** buf,const char * const * db_array)742 cgetfirst(char **buf, const char * const *db_array)
743 {
744
745 _DIAGASSERT(buf != NULL);
746 _DIAGASSERT(db_array != NULL);
747
748 (void)cgetclose();
749 return cgetnext(buf, db_array);
750 }
751
752 static FILE *pfp;
753 static int slash;
754 static const char * const *dbp;
755
756 int
cgetclose(void)757 cgetclose(void)
758 {
759 if (pfp != NULL) {
760 (void)fclose(pfp);
761 pfp = NULL;
762 }
763 dbp = NULL;
764 gottoprec = 0;
765 slash = 0;
766 return 0;
767 }
768
769 /*
770 * Cgetnext() gets either the first or next entry in the logical database
771 * specified by db_array. It returns 0 upon completion of the database, 1
772 * upon returning an entry with more remaining, and -1 if an error occurs.
773 */
774 /* coverity[+alloc : arg-*0] */
775 int
cgetnext(char ** bp,const char * const * db_array)776 cgetnext(char **bp, const char * const *db_array)
777 {
778 size_t len = 0;
779 int status, done;
780 char *cp, *line, *rp, *np, buf[BSIZE], nbuf[BSIZE];
781 size_t dummy;
782
783 _DIAGASSERT(bp != NULL);
784 _DIAGASSERT(db_array != NULL);
785
786 if (dbp == NULL)
787 dbp = db_array;
788
789 if (pfp == NULL && (pfp = fopen(*dbp, "re")) == NULL) {
790 (void)cgetclose();
791 return -1;
792 }
793 for (;;) {
794 if (toprec != NULL && !gottoprec) {
795 gottoprec = 1;
796 line = toprec;
797 } else {
798 line = fgetln(pfp, &len);
799 if (line == NULL) {
800 if (pfp == NULL)
801 return -1;
802 if (ferror(pfp)) {
803 (void)cgetclose();
804 return -1;
805 } else {
806 (void)fclose(pfp);
807 pfp = NULL;
808 if (*++dbp == NULL) {
809 (void)cgetclose();
810 return 0;
811 } else if ((pfp =
812 fopen(*dbp, "re")) == NULL) {
813 (void)cgetclose();
814 return -1;
815 } else
816 continue;
817 }
818 } else
819 line[len - 1] = '\0';
820 if (len == 1) {
821 slash = 0;
822 continue;
823 }
824 if (isspace((unsigned char)*line) ||
825 *line == ':' || *line == '#' || slash) {
826 if (line[len - 2] == '\\')
827 slash = 1;
828 else
829 slash = 0;
830 continue;
831 }
832 if (line[len - 2] == '\\')
833 slash = 1;
834 else
835 slash = 0;
836 }
837
838
839 /*
840 * Line points to a name line.
841 */
842 if (len > sizeof(nbuf))
843 return -1;
844 done = 0;
845 np = nbuf;
846 for (;;) {
847 for (cp = line; *cp != '\0'; cp++) {
848 if (*cp == ':') {
849 *np++ = ':';
850 done = 1;
851 break;
852 }
853 if (*cp == '\\')
854 break;
855 *np++ = *cp;
856 }
857 if (done) {
858 *np = '\0';
859 break;
860 } else { /* name field extends beyond the line */
861 line = fgetln(pfp, &len);
862 if (line == NULL && pfp) {
863 if (ferror(pfp)) {
864 (void)cgetclose();
865 return -1;
866 }
867 (void)fclose(pfp);
868 pfp = NULL;
869 *np = '\0';
870 break;
871 } else
872 line[len - 1] = '\0';
873 }
874 }
875 if (len > sizeof(buf))
876 return -1;
877 rp = buf;
878 for (cp = nbuf; *cp != '\0'; cp++)
879 if (*cp == '|' || *cp == ':')
880 break;
881 else
882 *rp++ = *cp;
883
884 *rp = '\0';
885 /*
886 * XXX
887 * Last argument of getent here should be nbuf if we want true
888 * sequential access in the case of duplicates.
889 * With NULL, getent will return the first entry found
890 * rather than the duplicate entry record. This is a
891 * matter of semantics that should be resolved.
892 */
893 status = getent(bp, &dummy, db_array, -1, buf, 0, NULL);
894 if (status == -2 || status == -3)
895 (void)cgetclose();
896
897 return status + 1;
898 }
899 /* NOTREACHED */
900 }
901
902 /*
903 * Cgetstr retrieves the value of the string capability cap from the
904 * capability record pointed to by buf. A pointer to a decoded, NUL
905 * terminated, malloc'd copy of the string is returned in the char *
906 * pointed to by str. The length of the string not including the trailing
907 * NUL is returned on success, -1 if the requested string capability
908 * couldn't be found, -2 if a system error was encountered (storage
909 * allocation failure).
910 */
911 int
cgetstr(char * buf,const char * cap,char ** str)912 cgetstr(char *buf, const char *cap, char **str)
913 {
914 u_int m_room;
915 const char *bp;
916 char *mp;
917 ptrdiff_t len;
918 char *mem, *newmem;
919
920 _DIAGASSERT(buf != NULL);
921 _DIAGASSERT(cap != NULL);
922 _DIAGASSERT(str != NULL);
923
924 /*
925 * Find string capability cap
926 */
927 bp = cgetcap(buf, cap, '=');
928 if (bp == 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 if (*bp == '^') {
950 bp++;
951 if (*bp == ':' || *bp == '\0')
952 break; /* drop unfinished escape */
953 *mp++ = *bp++ & 037;
954 } else if (*bp == '\\') {
955 bp++;
956 if (*bp == ':' || *bp == '\0')
957 break; /* drop unfinished escape */
958 if ('0' <= *bp && *bp <= '7') {
959 int n, i;
960
961 n = 0;
962 i = 3; /* maximum of three octal digits */
963 do {
964 n = n * 8 + (*bp++ - '0');
965 } while (--i && '0' <= *bp && *bp <= '7');
966 *mp++ = n;
967 }
968 else switch (*bp++) {
969 case 'b': case 'B':
970 *mp++ = '\b';
971 break;
972 case 't': case 'T':
973 *mp++ = '\t';
974 break;
975 case 'n': case 'N':
976 *mp++ = '\n';
977 break;
978 case 'f': case 'F':
979 *mp++ = '\f';
980 break;
981 case 'r': case 'R':
982 *mp++ = '\r';
983 break;
984 case 'e': case 'E':
985 *mp++ = ESC;
986 break;
987 case 'c': case 'C':
988 *mp++ = ':';
989 break;
990 default:
991 /*
992 * Catches '\', '^', and
993 * everything else.
994 */
995 *mp++ = *(bp-1);
996 break;
997 }
998 } else
999 *mp++ = *bp++;
1000 m_room--;
1001
1002 /*
1003 * Enforce loop invariant: if no room left in current
1004 * buffer, try to get some more.
1005 */
1006 if (m_room == 0) {
1007 size_t size = mp - mem;
1008
1009 if ((newmem = realloc(mem, size + SFRAG)) == NULL) {
1010 free(mem);
1011 return -2;
1012 }
1013 mem = newmem;
1014 m_room = SFRAG;
1015 mp = mem + size;
1016 }
1017 }
1018 *mp++ = '\0'; /* loop invariant let's us do this */
1019 m_room--;
1020 len = mp - mem - 1;
1021
1022 /*
1023 * Give back any extra memory and return value and success.
1024 */
1025 if (m_room != 0) {
1026 if ((newmem = realloc(mem, (size_t)(mp - mem))) == NULL) {
1027 free(mem);
1028 return -2;
1029 }
1030 mem = newmem;
1031 }
1032 *str = mem;
1033 _DIAGASSERT(__type_fit(int, len));
1034 return (int)len;
1035 }
1036
1037 /*
1038 * Cgetustr retrieves the value of the string capability cap from the
1039 * capability record pointed to by buf. The difference between cgetustr()
1040 * and cgetstr() is that cgetustr does not decode escapes but rather treats
1041 * all characters literally. A pointer to a NUL terminated malloc'd
1042 * copy of the string is returned in the char pointed to by str. The
1043 * length of the string not including the trailing NUL is returned on success,
1044 * -1 if the requested string capability couldn't be found, -2 if a system
1045 * error was encountered (storage allocation failure).
1046 */
1047 int
cgetustr(char * buf,const char * cap,char ** str)1048 cgetustr(char *buf, const char *cap, char **str)
1049 {
1050 u_int m_room;
1051 const char *bp;
1052 char *mp;
1053 size_t len;
1054 char *mem, *newmem;
1055
1056 _DIAGASSERT(buf != NULL);
1057 _DIAGASSERT(cap != NULL);
1058 _DIAGASSERT(str != NULL);
1059
1060 /*
1061 * Find string capability cap
1062 */
1063 if ((bp = cgetcap(buf, cap, '=')) == NULL)
1064 return -1;
1065
1066 /*
1067 * Conversion / storage allocation loop ... Allocate memory in
1068 * chunks SFRAG in size.
1069 */
1070 if ((mem = malloc(SFRAG)) == NULL) {
1071 errno = ENOMEM;
1072 return -2; /* couldn't even allocate the first fragment */
1073 }
1074 m_room = SFRAG;
1075 mp = mem;
1076
1077 while (*bp != ':' && *bp != '\0') {
1078 /*
1079 * Loop invariants:
1080 * There is always room for one more character in mem.
1081 * Mp always points just past last character in mem.
1082 * Bp always points at next character in buf.
1083 */
1084 *mp++ = *bp++;
1085 m_room--;
1086
1087 /*
1088 * Enforce loop invariant: if no room left in current
1089 * buffer, try to get some more.
1090 */
1091 if (m_room == 0) {
1092 size_t size = mp - mem;
1093
1094 if ((newmem = realloc(mem, size + SFRAG)) == NULL) {
1095 free(mem);
1096 return -2;
1097 }
1098 mem = newmem;
1099 m_room = SFRAG;
1100 mp = mem + size;
1101 }
1102 }
1103 *mp++ = '\0'; /* loop invariant let's us do this */
1104 m_room--;
1105 len = mp - mem - 1;
1106
1107 /*
1108 * Give back any extra memory and return value and success.
1109 */
1110 if (m_room != 0) {
1111 if ((newmem = realloc(mem, (size_t)(mp - mem))) == NULL) {
1112 free(mem);
1113 return -2;
1114 }
1115 mem = newmem;
1116 }
1117 *str = mem;
1118 _DIAGASSERT(__type_fit(int, len));
1119 return (int)len;
1120 }
1121
1122 /*
1123 * Cgetnum retrieves the value of the numeric capability cap from the
1124 * capability record pointed to by buf. The numeric value is returned in
1125 * the long pointed to by num. 0 is returned on success, -1 if the requested
1126 * numeric capability couldn't be found.
1127 */
1128 int
cgetnum(char * buf,const char * cap,long * num)1129 cgetnum(char *buf, const char *cap, long *num)
1130 {
1131 long n;
1132 int base, digit;
1133 const char *bp;
1134
1135 _DIAGASSERT(buf != NULL);
1136 _DIAGASSERT(cap != NULL);
1137 _DIAGASSERT(num != NULL);
1138
1139 /*
1140 * Find numeric capability cap
1141 */
1142 bp = cgetcap(buf, cap, '#');
1143 if (bp == NULL)
1144 return -1;
1145
1146 /*
1147 * Look at value and determine numeric base:
1148 * 0x... or 0X... hexadecimal,
1149 * else 0... octal,
1150 * else decimal.
1151 */
1152 if (*bp == '0') {
1153 bp++;
1154 if (*bp == 'x' || *bp == 'X') {
1155 bp++;
1156 base = 16;
1157 } else
1158 base = 8;
1159 } else
1160 base = 10;
1161
1162 /*
1163 * Conversion loop ...
1164 */
1165 n = 0;
1166 for (;;) {
1167 if ('0' <= *bp && *bp <= '9')
1168 digit = *bp - '0';
1169 else if ('a' <= *bp && *bp <= 'f')
1170 digit = 10 + *bp - 'a';
1171 else if ('A' <= *bp && *bp <= 'F')
1172 digit = 10 + *bp - 'A';
1173 else
1174 break;
1175
1176 if (digit >= base)
1177 break;
1178
1179 n = n * base + digit;
1180 bp++;
1181 }
1182
1183 /*
1184 * Return value and success.
1185 */
1186 *num = n;
1187 return 0;
1188 }
1189
1190
1191 /*
1192 * Compare name field of record.
1193 */
1194 static int
nfcmp(char * nf,char * rec)1195 nfcmp(char *nf, char *rec)
1196 {
1197 char *cp, tmp;
1198 int ret;
1199
1200 _DIAGASSERT(nf != NULL);
1201 _DIAGASSERT(rec != NULL);
1202
1203 for (cp = rec; *cp != ':'; cp++)
1204 continue;
1205
1206 tmp = *(cp + 1);
1207 *(cp + 1) = '\0';
1208 ret = strcmp(nf, rec);
1209 *(cp + 1) = tmp;
1210
1211 return ret;
1212 }
1213