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
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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 1.5 2005/01/31 22:29:15 dillon 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.
91 topreclen = strlen(ent);
92 if ((toprec = malloc (topreclen + 1)) == NULL) {
97 (void)strcpy(toprec, ent);
102 * Cgetcap searches the capability record buf for the capability cap with
103 * type `type'. A pointer to the value of cap is returned on success, NULL
104 * if the requested capability couldn't be found.
106 * Specifying a type of ':' means that nothing should follow cap (:cap:).
107 * In this case a pointer to the terminating ':' or NUL will be returned if
110 * If (cap, '@') or (cap, terminator, '@') is found before (cap, terminator)
114 cgetcap(buf, cap, type)
123 * Skip past the current capability field - it's either the
124 * name field if this is the first time through the loop, or
125 * the remainder of a field whose name failed to match cap.
135 * Try to match (cap, type) in buf.
137 for (cp = cap; *cp == *bp && *bp != '\0'; cp++, bp++)
144 if (*bp != '\0' && *bp != ':')
151 return (*bp == '@' ? NULL : bp);
157 * Cgetent extracts the capability record name from the NULL terminated file
158 * array db_array and returns a pointer to a malloc'd copy of it in buf.
159 * Buf must be retained through all subsequent calls to cgetcap, cgetnum,
160 * cgetflag, and cgetstr, but may then be free'd. 0 is returned on success,
161 * -1 if the requested record couldn't be found, -2 if a system error was
162 * encountered (couldn't open/read a file, etc.), and -3 if a potential
163 * reference loop is detected.
166 cgetent(buf, db_array, name)
167 char **buf, **db_array, *name;
171 return (getent(buf, &dummy, db_array, -1, name, 0, NULL));
175 * Getent implements the functions of cgetent. If fd is non-negative,
176 * *db_array has already been opened and fd is the open file descriptor. We
177 * do this to save time and avoid using up file descriptors for tc=
180 * Getent returns the same success/failure codes as cgetent. On success, a
181 * pointer to a malloc'ed capability record with all tc= capabilities fully
182 * expanded and its length (not including trailing ASCII NUL) are left in
186 * + Allocate memory incrementally as needed in chunks of size BFRAG
187 * for capability buffer.
188 * + Recurse for each tc=name and interpolate result. Stop when all
189 * names interpolated, a name can't be found, or depth exceeds
193 getent(cap, len, db_array, fd, name, depth, nfield)
194 char **cap, **db_array, *name, *nfield;
199 char *r_end, *rp, **db_p;
200 int myfd, eof, foundit, retval, clen;
203 char pbuf[_POSIX_PATH_MAX];
206 * Return with ``loop detected'' error if we've recursed more than
207 * MAX_RECURSION times.
209 if (depth > MAX_RECURSION)
213 * Check if we have a top record from cgetset().
215 if (depth == 0 && toprec != NULL && cgetmatch(toprec, name) == 0) {
216 if ((record = malloc (topreclen + BFRAG)) == NULL) {
220 (void)strcpy(record, toprec);
223 rp = record + topreclen + 1;
228 * Allocate first chunk of memory.
230 if ((record = malloc(BFRAG)) == NULL) {
234 r_end = record + BFRAG;
237 * Loop through database array until finding the record.
240 for (db_p = db_array; *db_p != NULL; db_p++) {
244 * Open database if not already open.
248 (void)lseek(fd, (off_t)0, SEEK_SET);
251 (void)snprintf(pbuf, sizeof(pbuf), "%s.db", *db_p);
252 if ((capdbp = dbopen(pbuf, O_RDONLY, 0, DB_HASH, 0))
255 retval = cdbget(capdbp, &record, name);
257 /* no record available */
258 (void)capdbp->close(capdbp);
261 /* save the data; close frees it */
262 clen = strlen(record);
263 cbuf = malloc(clen + 1);
264 memcpy(cbuf, record, clen + 1);
265 if (capdbp->close(capdbp) < 0) {
273 fd = _open(*db_p, O_RDONLY, 0);
280 * Find the requested capability record ...
289 * There is always room for one more character in record.
290 * R_end always points just past end of record.
291 * Rp always points just past last character in record.
292 * B_end always points just past last character in buf.
293 * Bp always points at next character in buf.
300 * Read in a line implementing (\, newline)
308 n = _read(fd, buf, sizeof(buf));
327 if (rp > record && *(rp-1) == '\\') {
336 * Enforce loop invariant: if no room
337 * left in record buffer, try to get
345 newsize = r_end - record + BFRAG;
346 record = reallocf(record, newsize);
347 if (record == NULL) {
353 r_end = record + newsize;
357 /* loop invariant let's us do this */
361 * If encountered eof check next file.
367 * Toss blank lines and comments.
369 if (*record == '\0' || *record == '#')
373 * See if this is the record we want ...
375 if (cgetmatch(record, name) == 0) {
376 if (nfield == NULL || !nfcmp(nfield, record)) {
378 break; /* found it! */
393 * Got the capability record, but now we have to expand all tc=name
394 * references in it ...
400 int diff, iret, tclen;
401 char *icap, *scan, *tc, *tcstart, *tcend;
405 * There is room for one more character in record.
406 * R_end points just past end of record.
407 * Rp points just past last character in record.
408 * Scan points at remainder of record that needs to be
409 * scanned for tc=name constructs.
414 if ((tc = cgetcap(scan, "tc", '=')) == NULL)
418 * Find end of tc=name and stomp on the trailing `:'
419 * (if present) so we can use it to call ourselves.
434 iret = getent(&icap, &ilen, db_p, fd, tc, depth+1,
436 newicap = icap; /* Put into a register. */
448 /* couldn't resolve tc */
457 /* not interested in name field of tc'ed record */
465 newilen -= s - newicap;
468 /* make sure interpolated record is `:'-terminated */
471 *s = ':'; /* overwrite NUL with : */
476 * Make sure there's enough room to insert the
479 diff = newilen - tclen;
480 if (diff >= r_end - rp) {
481 u_int pos, tcpos, tcposend;
485 newsize = r_end - record + diff + BFRAG;
486 tcpos = tcstart - record;
487 tcposend = tcend - record;
488 record = reallocf(record, newsize);
489 if (record == NULL) {
496 r_end = record + newsize;
498 tcstart = record + tcpos;
499 tcend = record + tcposend;
503 * Insert tc'ed record into our record.
505 s = tcstart + newilen;
506 bcopy(tcend, s, rp - tcend);
507 bcopy(newicap, tcstart, newilen);
512 * Start scan on `:' so next cgetcap works properly
513 * (cgetcap always skips first field).
520 * Close file (if we opened it), give back any extra memory, and
521 * return capability, length and success.
525 *len = rp - record - 1; /* don't count NUL */
528 reallocf(record, (size_t)(rp - record))) == NULL) {
540 cdbget(capdbp, bp, name)
547 key.size = strlen(name);
550 /* Get the reference. */
551 switch(capdbp->get(capdbp, &key, &data, 0)) {
558 /* If not an index to another record, leave. */
559 if (((char *)data.data)[0] != SHADOW)
562 key.data = (char *)data.data + 1;
563 key.size = data.size - 1;
566 *bp = (char *)data.data + 1;
567 return (((char *)(data.data))[0] == TCERR ? 1 : 0);
571 * Cgetmatch will return 0 if name is one of the names of the capability
572 * record buf, -1 if not.
581 * Start search at beginning of record.
586 * Try to match a record name.
591 if (*bp == '|' || *bp == ':' || *bp == '\0')
600 * Match failed, skip to next name in record.
602 bp--; /* a '|' or ':' may have stopped the match */
604 if (*bp == '\0' || *bp == ':')
605 return (-1); /* match failed totally */
608 break; /* found next name */
617 cgetfirst(buf, db_array)
618 char **buf, **db_array;
621 return (cgetnext(buf, db_array));
642 * Cgetnext() gets either the first or next entry in the logical database
643 * specified by db_array. It returns 0 upon completion of the database, 1
644 * upon returning an entry with more remaining, and -1 if an error occurs.
647 cgetnext(bp, db_array)
652 int done, hadreaderr, i, savederrno, status;
653 char *cp, *line, *rp, *np, buf[BSIZE], nbuf[BSIZE];
659 if (pfp == NULL && (pfp = fopen(*dbp, "r")) == NULL) {
664 if (toprec && !gottoprec) {
668 line = fgetln(pfp, &len);
669 if (line == NULL && pfp) {
670 hadreaderr = ferror(pfp);
680 if (*++dbp == NULL) {
684 fopen(*dbp, "r")) == NULL) {
691 line[len - 1] = '\0';
696 if (isspace((unsigned char)*line) ||
697 *line == ':' || *line == '#' || slash) {
698 if (line[len - 2] == '\\')
704 if (line[len - 2] == '\\')
712 * Line points to a name line.
718 for (cp = line; *cp != '\0'; cp++) {
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);
749 line[len - 1] = '\0';
753 for(cp = nbuf; *cp != '\0'; cp++)
754 if (*cp == '|' || *cp == ':')
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.
768 status = getent(bp, &dummy, db_array, -1, buf, 0, NULL);
769 if (status == -2 || status == -3)
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).
787 cgetstr(buf, cap, str)
797 * Find string capability cap
799 bp = cgetcap(buf, cap, '=');
804 * Conversion / storage allocation loop ... Allocate memory in
805 * chunks SFRAG in size.
807 if ((mem = malloc(SFRAG)) == NULL) {
809 return (-2); /* couldn't even allocate the first fragment */
814 while (*bp != ':' && *bp != '\0') {
817 * There is always room for one more character in mem.
818 * Mp always points just past last character in mem.
819 * Bp always points at next character in buf.
823 if (*bp == ':' || *bp == '\0')
824 break; /* drop unfinished escape */
830 } else if (*bp == '\\') {
832 if (*bp == ':' || *bp == '\0')
833 break; /* drop unfinished escape */
834 if ('0' <= *bp && *bp <= '7') {
838 i = 3; /* maximum of three octal digits */
840 n = n * 8 + (*bp++ - '0');
841 } while (--i && '0' <= *bp && *bp <= '7');
844 else switch (*bp++) {
868 * Catches '\', '^', and
879 * Enforce loop invariant: if no room left in current
880 * buffer, try to get some more.
883 size_t size = mp - mem;
885 if ((mem = reallocf(mem, size + SFRAG)) == NULL)
891 *mp++ = '\0'; /* loop invariant let's us do this */
896 * Give back any extra memory and return value and success.
899 if ((mem = reallocf(mem, (size_t)(mp - mem))) == NULL)
906 * Cgetustr retrieves the value of the string capability cap from the
907 * capability record pointed to by buf. The difference between cgetustr()
908 * and cgetstr() is that cgetustr does not decode escapes but rather treats
909 * all characters literally. A pointer to a NUL terminated malloc'd
910 * copy of the string is returned in the char pointed to by str. The
911 * length of the string not including the trailing NUL is returned on success,
912 * -1 if the requested string capability couldn't be found, -2 if a system
913 * error was encountered (storage allocation failure).
916 cgetustr(buf, cap, str)
917 char *buf, *cap, **str;
925 * Find string capability cap
927 if ((bp = cgetcap(buf, cap, '=')) == NULL)
931 * Conversion / storage allocation loop ... Allocate memory in
932 * chunks SFRAG in size.
934 if ((mem = malloc(SFRAG)) == NULL) {
936 return (-2); /* couldn't even allocate the first fragment */
941 while (*bp != ':' && *bp != '\0') {
944 * There is always room for one more character in mem.
945 * Mp always points just past last character in mem.
946 * Bp always points at next character in buf.
952 * Enforce loop invariant: if no room left in current
953 * buffer, try to get some more.
956 size_t size = mp - mem;
958 if ((mem = reallocf(mem, size + SFRAG)) == NULL)
964 *mp++ = '\0'; /* loop invariant let's us do this */
969 * Give back any extra memory and return value and success.
972 if ((mem = reallocf(mem, (size_t)(mp - mem))) == NULL)
979 * Cgetnum retrieves the value of the numeric capability cap from the
980 * capability record pointed to by buf. The numeric value is returned in
981 * the long pointed to by num. 0 is returned on success, -1 if the requested
982 * numeric capability couldn't be found.
985 cgetnum(buf, cap, num)
994 * Find numeric capability cap
996 bp = cgetcap(buf, cap, '#');
1001 * Look at value and determine numeric base:
1002 * 0x... or 0X... hexadecimal,
1008 if (*bp == 'x' || *bp == 'X') {
1017 * Conversion loop ...
1021 if ('0' <= *bp && *bp <= '9')
1023 else if ('a' <= *bp && *bp <= 'f')
1024 digit = 10 + *bp - 'a';
1025 else if ('A' <= *bp && *bp <= 'F')
1026 digit = 10 + *bp - 'A';
1033 n = n * base + digit;
1038 * Return value and success.
1046 * Compare name field of record.
1055 for (cp = rec; *cp != ':'; cp++)
1060 ret = strcmp(nf, rec);