2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1992, 1993
5 * The Regents of the University of California. All rights reserved.
7 * This code is derived from software contributed to Berkeley by
8 * Casey Leedom of Lawrence Livermore National Laboratory.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
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.
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
35 #if defined(LIBC_SCCS) && !defined(lint)
36 static char sccsid[] = "@(#)getcap.c 8.3 (Berkeley) 3/25/94";
37 #endif /* LIBC_SCCS and not lint */
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
41 #include "namespace.h"
42 #include <sys/types.h>
52 #include "un-namespace.h"
58 #define ESC ('[' & 037) /* ASCII ESC */
59 #define MAX_RECURSION 32 /* maximum getent recursion */
60 #define SFRAG 100 /* cgetstr mallocs in SFRAG chunks */
64 #define SHADOW (char)2
66 static size_t topreclen; /* toprec length */
67 static char *toprec; /* Additional record specified by cgetset() */
68 static int gottoprec; /* Flag indicating retrieval of toprecord */
70 static int cdbget(DB *, char **, const char *);
71 static int getent(char **, u_int *, char **, int, const char *, int, char *);
72 static int nfcmp(char *, char *);
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.
80 cgetset(const char *ent)
89 topreclen = strlen(ent);
90 if ((toprec = malloc (topreclen + 1)) == NULL) {
95 (void)strcpy(toprec, ent);
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.
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
108 * If (cap, '@') or (cap, terminator, '@') is found before (cap, terminator)
112 cgetcap(char *buf, const 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, const 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, const char *name,
190 int depth, char *nfield)
193 char *r_end, *rp, **db_p;
194 int myfd, eof, foundit, retval;
197 char pbuf[_POSIX_PATH_MAX];
200 * Return with ``loop detected'' error if we've recursed more than
201 * MAX_RECURSION times.
203 if (depth > MAX_RECURSION)
207 * Check if we have a top record from cgetset().
209 if (depth == 0 && toprec != NULL && cgetmatch(toprec, name) == 0) {
210 if ((record = malloc (topreclen + BFRAG)) == NULL) {
214 (void)strcpy(record, toprec);
217 rp = record + topreclen + 1;
222 * Allocate first chunk of memory.
224 if ((record = malloc(BFRAG)) == NULL) {
228 r_end = record + BFRAG;
231 * Loop through database array until finding the record.
234 for (db_p = db_array; *db_p != NULL; db_p++) {
238 * Open database if not already open.
242 (void)lseek(fd, (off_t)0, SEEK_SET);
245 (void)snprintf(pbuf, sizeof(pbuf), "%s.db", *db_p);
246 if ((capdbp = dbopen(pbuf, O_RDONLY, 0, DB_HASH, 0))
249 retval = cdbget(capdbp, &record, name);
251 /* no record available */
252 (void)capdbp->close(capdbp);
255 /* save the data; close frees it */
256 cbuf = strdup(record);
257 if (capdbp->close(capdbp) < 0) {
269 fd = _open(*db_p, O_RDONLY | O_CLOEXEC, 0);
276 * Find the requested capability record ...
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.
296 * Read in a line implementing (\, newline)
304 n = _read(fd, buf, sizeof(buf));
323 if (rp > record && *(rp-1) == '\\') {
332 * Enforce loop invariant: if no room
333 * left in record buffer, try to get
341 newsize = r_end - record + BFRAG;
342 record = reallocf(record, newsize);
343 if (record == NULL) {
349 r_end = record + newsize;
353 /* loop invariant let's us do this */
357 * If encountered eof check next file.
363 * Toss blank lines and comments.
365 if (*record == '\0' || *record == '#')
369 * See if this is the record we want ...
371 if (cgetmatch(record, name) == 0) {
372 if (nfield == NULL || !nfcmp(nfield, record)) {
374 break; /* found it! */
389 * Got the capability record, but now we have to expand all tc=name
390 * references in it ...
396 int diff, iret, tclen;
397 char *icap, *scan, *tc, *tcstart, *tcend;
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.
410 if ((tc = cgetcap(scan, "tc", '=')) == NULL)
414 * Find end of tc=name and stomp on the trailing `:'
415 * (if present) so we can use it to call ourselves.
430 iret = getent(&icap, &ilen, db_p, fd, tc, depth+1,
432 newicap = icap; /* Put into a register. */
444 /* couldn't resolve tc */
453 /* not interested in name field of tc'ed record */
461 newilen -= s - newicap;
464 /* make sure interpolated record is `:'-terminated */
467 *s = ':'; /* overwrite NUL with : */
472 * Make sure there's enough room to insert the
475 diff = newilen - tclen;
476 if (diff >= r_end - rp) {
477 u_int pos, tcpos, tcposend;
481 newsize = r_end - record + diff + BFRAG;
482 tcpos = tcstart - record;
483 tcposend = tcend - record;
484 record = reallocf(record, newsize);
485 if (record == NULL) {
492 r_end = record + newsize;
494 tcstart = record + tcpos;
495 tcend = record + tcposend;
499 * Insert tc'ed record into our record.
501 s = tcstart + newilen;
502 bcopy(tcend, s, rp - tcend);
503 bcopy(newicap, tcstart, newilen);
508 * Start scan on `:' so next cgetcap works properly
509 * (cgetcap always skips first field).
516 * Close file (if we opened it), give back any extra memory, and
517 * return capability, length and success.
521 *len = rp - record - 1; /* don't count NUL */
524 reallocf(record, (size_t)(rp - record))) == NULL) {
536 cdbget(DB *capdbp, char **bp, const char *name)
541 namebuf = strdup(name);
545 key.size = strlen(namebuf);
548 /* Get the reference. */
549 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;
568 return (((char *)(data.data))[0] == TCERR ? 1 : 0);
572 * Cgetmatch will return 0 if name is one of the names of the capability
573 * record buf, -1 if not.
576 cgetmatch(const char *buf, const char *name)
580 if (name == NULL || *name == '\0')
584 * Start search at beginning of record.
589 * Try to match a record name.
594 if (*bp == '|' || *bp == ':' || *bp == '\0')
603 * Match failed, skip to next name in record.
605 bp--; /* a '|' or ':' may have stopped the match */
607 if (*bp == '\0' || *bp == ':')
608 return (-1); /* match failed totally */
611 break; /* found next name */
620 cgetfirst(char **buf, char **db_array)
623 return (cgetnext(buf, db_array));
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.
649 cgetnext(char **bp, char **db_array)
652 int done, hadreaderr, savederrno, status;
653 char *cp, *line, *rp, *np, buf[BSIZE], nbuf[BSIZE];
659 if (pfp == NULL && (pfp = fopen(*dbp, "re")) == 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, "re")) == 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.
717 for (cp = line; *cp != '\0'; cp++) {
730 } else { /* name field extends beyond the line */
731 line = fgetln(pfp, &len);
732 if (line == NULL && pfp) {
733 /* Name extends beyond the EOF! */
734 hadreaderr = ferror(pfp);
748 line[len - 1] = '\0';
752 for(cp = nbuf; *cp != '\0'; cp++)
753 if (*cp == '|' || *cp == ':')
761 * Last argument of getent here should be nbuf if we want true
762 * sequential access in the case of duplicates.
763 * With NULL, getent will return the first entry found
764 * rather than the duplicate entry record. This is a
765 * matter of semantics that should be resolved.
767 status = getent(bp, &dummy, db_array, -1, buf, 0, NULL);
768 if (status == -2 || status == -3)
777 * Cgetstr retrieves the value of the string capability cap from the
778 * capability record pointed to by buf. A pointer to a decoded, NUL
779 * terminated, malloc'd copy of the string is returned in the char *
780 * pointed to by str. The length of the string not including the trailing
781 * NUL is returned on success, -1 if the requested string capability
782 * couldn't be found, -2 if a system error was encountered (storage
783 * allocation failure).
786 cgetstr(char *buf, const char *cap, char **str)
794 * Find string capability cap
796 bp = cgetcap(buf, cap, '=');
801 * Conversion / storage allocation loop ... Allocate memory in
802 * chunks SFRAG in size.
804 if ((mem = malloc(SFRAG)) == NULL) {
806 return (-2); /* couldn't even allocate the first fragment */
811 while (*bp != ':' && *bp != '\0') {
814 * There is always room for one more character in mem.
815 * Mp always points just past last character in mem.
816 * Bp always points at next character in buf.
820 if (*bp == ':' || *bp == '\0')
821 break; /* drop unfinished escape */
827 } else if (*bp == '\\') {
829 if (*bp == ':' || *bp == '\0')
830 break; /* drop unfinished escape */
831 if ('0' <= *bp && *bp <= '7') {
835 i = 3; /* maximum of three octal digits */
837 n = n * 8 + (*bp++ - '0');
838 } while (--i && '0' <= *bp && *bp <= '7');
841 else switch (*bp++) {
865 * Catches '\', '^', and
876 * Enforce loop invariant: if no room left in current
877 * buffer, try to get some more.
880 size_t size = mp - mem;
882 if ((mem = reallocf(mem, size + SFRAG)) == NULL)
888 *mp++ = '\0'; /* loop invariant let's us do this */
893 * Give back any extra memory and return value and success.
896 if ((mem = reallocf(mem, (size_t)(mp - mem))) == NULL)
903 * Cgetustr retrieves the value of the string capability cap from the
904 * capability record pointed to by buf. The difference between cgetustr()
905 * and cgetstr() is that cgetustr does not decode escapes but rather treats
906 * all characters literally. A pointer to a NUL terminated malloc'd
907 * copy of the string is returned in the char pointed to by str. The
908 * length of the string not including the trailing NUL is returned on success,
909 * -1 if the requested string capability couldn't be found, -2 if a system
910 * error was encountered (storage allocation failure).
913 cgetustr(char *buf, const char *cap, char **str)
921 * Find string capability cap
923 if ((bp = cgetcap(buf, cap, '=')) == NULL)
927 * Conversion / storage allocation loop ... Allocate memory in
928 * chunks SFRAG in size.
930 if ((mem = malloc(SFRAG)) == NULL) {
932 return (-2); /* couldn't even allocate the first fragment */
937 while (*bp != ':' && *bp != '\0') {
940 * There is always room for one more character in mem.
941 * Mp always points just past last character in mem.
942 * Bp always points at next character in buf.
948 * Enforce loop invariant: if no room left in current
949 * buffer, try to get some more.
952 size_t size = mp - mem;
954 if ((mem = reallocf(mem, size + SFRAG)) == NULL)
960 *mp++ = '\0'; /* loop invariant let's us do this */
965 * Give back any extra memory and return value and success.
968 if ((mem = reallocf(mem, (size_t)(mp - mem))) == NULL)
975 * Cgetnum retrieves the value of the numeric capability cap from the
976 * capability record pointed to by buf. The numeric value is returned in
977 * the long pointed to by num. 0 is returned on success, -1 if the requested
978 * numeric capability couldn't be found.
981 cgetnum(char *buf, const char *cap, long *num)
988 * Find numeric capability cap
990 bp = cgetcap(buf, cap, '#');
995 * Look at value and determine numeric base:
996 * 0x... or 0X... hexadecimal,
1002 if (*bp == 'x' || *bp == 'X') {
1011 * Conversion loop ...
1015 if ('0' <= *bp && *bp <= '9')
1017 else if ('a' <= *bp && *bp <= 'f')
1018 digit = 10 + *bp - 'a';
1019 else if ('A' <= *bp && *bp <= 'F')
1020 digit = 10 + *bp - 'A';
1027 n = n * base + digit;
1032 * Return value and success.
1040 * Compare name field of record.
1043 nfcmp(char *nf, char *rec)
1048 for (cp = rec; *cp != ':'; cp++)
1053 ret = strcmp(nf, rec);