2 * Copyright (c) 1992, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
6 * Casey Leedom of Lawrence Livermore National Laboratory.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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.
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
36 * $FreeBSD: src/lib/libc/gen/getcap.c,v 1.11.2.2 2001/01/15 06:48:09 gad Exp $
37 * $DragonFly: src/lib/libc/gen/getcap.c,v 1.7 2005/11/19 22:32:53 swildner Exp $
39 * @(#)getcap.c 8.3 (Berkeley) 3/25/94
42 #include "namespace.h"
43 #include <sys/types.h>
53 #include "un-namespace.h"
59 #define ESC ('[' & 037) /* ASCII ESC */
60 #define MAX_RECURSION 32 /* maximum getent recursion */
61 #define SFRAG 100 /* cgetstr mallocs in SFRAG chunks */
65 #define SHADOW (char)2
67 static size_t topreclen; /* toprec length */
68 static char *toprec; /* Additional record specified by cgetset() */
69 static int gottoprec; /* Flag indicating retrieval of toprecord */
71 static int cdbget (DB *, char **, char *);
72 static int getent (char **, u_int *, char **, int, char *, int, char *);
73 static int nfcmp (char *, char *);
76 * Cgetset() allows the addition of a user specified buffer to be added
77 * to the database array, in effect "pushing" the buffer on top of the
78 * virtual database. 0 is returned on success, -1 on failure.
90 topreclen = strlen(ent);
91 if ((toprec = malloc (topreclen + 1)) == NULL) {
101 * Cgetcap searches the capability record buf for the capability cap with
102 * type `type'. A pointer to the value of cap is returned on success, NULL
103 * if the requested capability couldn't be found.
105 * Specifying a type of ':' means that nothing should follow cap (:cap:).
106 * In this case a pointer to the terminating ':' or NUL will be returned if
109 * If (cap, '@') or (cap, terminator, '@') is found before (cap, terminator)
113 cgetcap(char *buf, char *cap, int type)
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.
132 * Try to match (cap, type) in buf.
134 for (cp = cap; *cp == *bp && *bp != '\0'; cp++, bp++)
141 if (*bp != '\0' && *bp != ':')
148 return (*bp == '@' ? NULL : bp);
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.
163 cgetent(char **buf, char **db_array, char *name)
167 return (getent(buf, &dummy, db_array, -1, name, 0, NULL));
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=
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
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
189 getent(char **cap, u_int *len, char **db_array, int fd, char *name, int depth,
193 char *r_end, *rp, **db_p;
194 int myfd, eof, foundit, retval, clen;
197 char pbuf[_POSIX_PATH_MAX];
203 * Return with ``loop detected'' error if we've recursed more than
204 * MAX_RECURSION times.
206 if (depth > MAX_RECURSION)
210 * Check if we have a top record from cgetset().
212 if (depth == 0 && toprec != NULL && cgetmatch(toprec, name) == 0) {
213 if ((record = malloc (topreclen + BFRAG)) == NULL) {
217 strcpy(record, toprec);
220 rp = record + topreclen + 1;
225 * Allocate first chunk of memory.
227 if ((record = malloc(BFRAG)) == NULL) {
231 r_end = record + BFRAG;
234 * Loop through database array until finding the record.
237 for (db_p = db_array; *db_p != NULL; db_p++) {
241 * Open database if not already open.
245 lseek(fd, (off_t)0, SEEK_SET);
248 snprintf(pbuf, sizeof(pbuf), "%s.db", *db_p);
249 if ((capdbp = dbopen(pbuf, O_RDONLY, 0, DB_HASH, 0))
252 retval = cdbget(capdbp, &record, name);
254 /* no record available */
255 capdbp->close(capdbp);
258 /* save the data; close frees it */
259 clen = strlen(record);
260 cbuf = malloc(clen + 1);
261 memcpy(cbuf, record, clen + 1);
262 if (capdbp->close(capdbp) < 0) {
270 fd = _open(*db_p, O_RDONLY, 0);
277 * Find the requested capability record ...
286 * There is always room for one more character in record.
287 * R_end always points just past end of record.
288 * Rp always points just past last character in record.
289 * B_end always points just past last character in buf.
290 * Bp always points at next character in buf.
297 * Read in a line implementing (\, newline)
305 n = _read(fd, buf, sizeof(buf));
324 if (rp > record && *(rp-1) == '\\') {
333 * Enforce loop invariant: if no room
334 * left in record buffer, try to get
342 newsize = r_end - record + BFRAG;
343 record = reallocf(record, newsize);
344 if (record == NULL) {
350 r_end = record + newsize;
354 /* loop invariant let's us do this */
358 * If encountered eof check next file.
364 * Toss blank lines and comments.
366 if (*record == '\0' || *record == '#')
370 * See if this is the record we want ...
372 if (cgetmatch(record, name) == 0) {
373 if (nfield == NULL || !nfcmp(nfield, record)) {
375 break; /* found it! */
390 * Got the capability record, but now we have to expand all tc=name
391 * references in it ...
397 int diff, iret, tclen;
398 char *icap, *scan, *tc, *tcstart, *tcend;
402 * There is room for one more character in record.
403 * R_end points just past end of record.
404 * Rp points just past last character in record.
405 * Scan points at remainder of record that needs to be
406 * scanned for tc=name constructs.
411 if ((tc = cgetcap(scan, "tc", '=')) == NULL)
415 * Find end of tc=name and stomp on the trailing `:'
416 * (if present) so we can use it to call ourselves.
431 iret = getent(&icap, &ilen, db_p, fd, tc, depth+1,
433 newicap = icap; /* Put into a register. */
445 /* couldn't resolve tc */
454 /* not interested in name field of tc'ed record */
462 newilen -= s - newicap;
465 /* make sure interpolated record is `:'-terminated */
468 *s = ':'; /* overwrite NUL with : */
473 * Make sure there's enough room to insert the
476 diff = newilen - tclen;
477 if (diff >= r_end - rp) {
478 u_int pos, tcpos, tcposend;
482 newsize = r_end - record + diff + BFRAG;
483 tcpos = tcstart - record;
484 tcposend = tcend - record;
485 record = reallocf(record, newsize);
486 if (record == NULL) {
493 r_end = record + newsize;
495 tcstart = record + tcpos;
496 tcend = record + tcposend;
500 * Insert tc'ed record into our record.
502 s = tcstart + newilen;
503 bcopy(tcend, s, rp - tcend);
504 bcopy(newicap, tcstart, newilen);
509 * Start scan on `:' so next cgetcap works properly
510 * (cgetcap always skips first field).
517 * Close file (if we opened it), give back any extra memory, and
518 * return capability, length and success.
522 *len = rp - record - 1; /* don't count NUL */
525 reallocf(record, (size_t)(rp - record))) == NULL) {
537 cdbget(DB *capdbp, char **bp, char *name)
542 key.size = strlen(name);
545 /* Get the reference. */
546 switch(capdbp->get(capdbp, &key, &data, 0)) {
553 /* If not an index to another record, leave. */
554 if (((char *)data.data)[0] != SHADOW)
557 key.data = (char *)data.data + 1;
558 key.size = data.size - 1;
561 *bp = (char *)data.data + 1;
562 return (((char *)(data.data))[0] == TCERR ? 1 : 0);
566 * Cgetmatch will return 0 if name is one of the names of the capability
567 * record buf, -1 if not.
570 cgetmatch(char *buf, char *name)
575 * Start search at beginning of record.
580 * Try to match a record name.
585 if (*bp == '|' || *bp == ':' || *bp == '\0')
594 * Match failed, skip to next name in record.
596 bp--; /* a '|' or ':' may have stopped the match */
598 if (*bp == '\0' || *bp == ':')
599 return (-1); /* match failed totally */
602 break; /* found next name */
611 cgetfirst(char **buf, char **db_array)
614 return (cgetnext(buf, db_array));
635 * Cgetnext() gets either the first or next entry in the logical database
636 * specified by db_array. It returns 0 upon completion of the database, 1
637 * upon returning an entry with more remaining, and -1 if an error occurs.
640 cgetnext(char **bp, char **db_array)
643 int done, hadreaderr, i, savederrno, status;
644 char *cp, *line, *rp, *np, buf[BSIZE], nbuf[BSIZE];
652 if (pfp == NULL && (pfp = fopen(*dbp, "r")) == NULL) {
657 if (toprec && !gottoprec) {
661 line = fgetln(pfp, &len);
662 if (line == NULL && pfp) {
663 hadreaderr = ferror(pfp);
673 if (*++dbp == NULL) {
677 fopen(*dbp, "r")) == NULL) {
684 line[len - 1] = '\0';
689 if (isspace((unsigned char)*line) ||
690 *line == ':' || *line == '#' || slash) {
691 if (line[len - 2] == '\\')
697 if (line[len - 2] == '\\')
705 * Line points to a name line.
711 for (cp = line; *cp != '\0'; cp++) {
724 } else { /* name field extends beyond the line */
725 line = fgetln(pfp, &len);
726 if (line == NULL && pfp) {
727 /* Name extends beyond the EOF! */
728 hadreaderr = ferror(pfp);
742 line[len - 1] = '\0';
746 for(cp = nbuf; *cp != '\0'; cp++)
747 if (*cp == '|' || *cp == ':')
755 * Last argument of getent here should be nbuf if we want true
756 * sequential access in the case of duplicates.
757 * With NULL, getent will return the first entry found
758 * rather than the duplicate entry record. This is a
759 * matter of semantics that should be resolved.
761 status = getent(bp, &dummy, db_array, -1, buf, 0, NULL);
762 if (status == -2 || status == -3)
771 * Cgetstr retrieves the value of the string capability cap from the
772 * capability record pointed to by buf. A pointer to a decoded, NUL
773 * terminated, malloc'd copy of the string is returned in the char *
774 * pointed to by str. The length of the string not including the trailing
775 * NUL is returned on success, -1 if the requested string capability
776 * couldn't be found, -2 if a system error was encountered (storage
777 * allocation failure).
780 cgetstr(char *buf, char *cap, char **str)
788 * Find string capability cap
790 bp = cgetcap(buf, cap, '=');
795 * Conversion / storage allocation loop ... Allocate memory in
796 * chunks SFRAG in size.
798 if ((mem = malloc(SFRAG)) == NULL) {
800 return (-2); /* couldn't even allocate the first fragment */
805 while (*bp != ':' && *bp != '\0') {
808 * There is always room for one more character in mem.
809 * Mp always points just past last character in mem.
810 * Bp always points at next character in buf.
814 if (*bp == ':' || *bp == '\0')
815 break; /* drop unfinished escape */
821 } else if (*bp == '\\') {
823 if (*bp == ':' || *bp == '\0')
824 break; /* drop unfinished escape */
825 if ('0' <= *bp && *bp <= '7') {
829 i = 3; /* maximum of three octal digits */
831 n = n * 8 + (*bp++ - '0');
832 } while (--i && '0' <= *bp && *bp <= '7');
835 else switch (*bp++) {
859 * Catches '\', '^', and
870 * Enforce loop invariant: if no room left in current
871 * buffer, try to get some more.
874 size_t size = mp - mem;
876 if ((mem = reallocf(mem, size + SFRAG)) == NULL)
882 *mp++ = '\0'; /* loop invariant let's us do this */
887 * Give back any extra memory and return value and success.
890 if ((mem = reallocf(mem, (size_t)(mp - mem))) == NULL)
897 * Cgetustr retrieves the value of the string capability cap from the
898 * capability record pointed to by buf. The difference between cgetustr()
899 * and cgetstr() is that cgetustr does not decode escapes but rather treats
900 * all characters literally. A pointer to a NUL terminated malloc'd
901 * copy of the string is returned in the char pointed to by str. The
902 * length of the string not including the trailing NUL is returned on success,
903 * -1 if the requested string capability couldn't be found, -2 if a system
904 * error was encountered (storage allocation failure).
907 cgetustr(char *buf, char *cap, char **str)
915 * Find string capability cap
917 if ((bp = cgetcap(buf, cap, '=')) == NULL)
921 * Conversion / storage allocation loop ... Allocate memory in
922 * chunks SFRAG in size.
924 if ((mem = malloc(SFRAG)) == NULL) {
926 return (-2); /* couldn't even allocate the first fragment */
931 while (*bp != ':' && *bp != '\0') {
934 * There is always room for one more character in mem.
935 * Mp always points just past last character in mem.
936 * Bp always points at next character in buf.
942 * Enforce loop invariant: if no room left in current
943 * buffer, try to get some more.
946 size_t size = mp - mem;
948 if ((mem = reallocf(mem, size + SFRAG)) == NULL)
954 *mp++ = '\0'; /* loop invariant let's us do this */
959 * Give back any extra memory and return value and success.
962 if ((mem = reallocf(mem, (size_t)(mp - mem))) == NULL)
969 * Cgetnum retrieves the value of the numeric capability cap from the
970 * capability record pointed to by buf. The numeric value is returned in
971 * the long pointed to by num. 0 is returned on success, -1 if the requested
972 * numeric capability couldn't be found.
975 cgetnum(char *buf, char *cap, long *num)
982 * Find numeric capability cap
984 bp = cgetcap(buf, cap, '#');
989 * Look at value and determine numeric base:
990 * 0x... or 0X... hexadecimal,
996 if (*bp == 'x' || *bp == 'X') {
1005 * Conversion loop ...
1009 if ('0' <= *bp && *bp <= '9')
1011 else if ('a' <= *bp && *bp <= 'f')
1012 digit = 10 + *bp - 'a';
1013 else if ('A' <= *bp && *bp <= 'F')
1014 digit = 10 + *bp - 'A';
1021 n = n * base + digit;
1026 * Return value and success.
1034 * Compare name field of record.
1037 nfcmp(char *nf, char *rec)
1042 for (cp = rec; *cp != ':'; cp++)
1047 ret = strcmp(nf, rec);