NetBSD-5.0.2/distrib/utils/libhack/getgrent.c
/* $NetBSD: getgrent.c,v 1.12 2005/09/14 15:54:53 drochner Exp $ */
/*
* Copyright (c) 1989, 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* Portions Copyright (c) 1994, Jason Downs. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* Copied from: lib/libc/gen/getgrent.c
* NetBSD: getgrent.c,v 1.46 2003/02/17 00:11:54 simonb Exp
* and then gutted, leaving only /etc/group support.
*/
#include <sys/cdefs.h>
#ifdef __weak_alias
#define endgrent _endgrent
#define getgrent _getgrent
#define getgrgid _getgrgid
#define getgrnam _getgrnam
#define getgrnam_r _getgrnam_r
#define setgrent _setgrent
#define setgroupent _setgroupent
#define getgrouplist _getgrouplist
__weak_alias(endgrent,_endgrent)
__weak_alias(getgrent,_getgrent)
__weak_alias(getgrgid,_getgrgid)
__weak_alias(getgrnam,_getgrnam)
__weak_alias(getgrnam_r,_getgrnam_r)
__weak_alias(setgrent,_setgrent)
__weak_alias(setgroupent,_setgroupent)
__weak_alias(getgrouplist,_getgrouplist)
#endif
#include <sys/param.h>
#include <grp.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
static FILE *_gr_fp;
static struct group _gr_group;
static int _gr_stayopen;
static int _gr_filesdone;
static int grscan(int, gid_t, const char *, const char *);
static int grstart(void);
static int grmatchline(int, gid_t, const char *, const char *);
#define MAXGRP 200
#define MAXLINELENGTH 1024
static __aconst char *members[MAXGRP];
static char grline[MAXLINELENGTH];
struct group *
getgrent(void)
{
if ((!_gr_fp && !grstart()) || !grscan(0, 0, NULL, NULL))
return (NULL);
return &_gr_group;
}
int
getgrnam_r(const char *name, struct group *grp, char *buffer,
size_t buflen, struct group **result)
{
struct group *gp, *bgp;
/*
* We blatantly cheat (don't provide reentrancy)
* and hope to get away with it
*/
*result = NULL;
bgp = (struct group*)buffer;
if (buflen < sizeof(struct group))
return ENOMEM;
gp = getgrnam(name);
if (gp) {
*bgp = *gp;
*result = bgp;
}
return (gp) ? ENOENT : 0;
}
struct group *
getgrnam(const char *name)
{
int rval;
if (!grstart())
return NULL;
rval = grscan(1, 0, name, NULL);
if (!_gr_stayopen)
endgrent();
return (rval) ? &_gr_group : NULL;
}
struct group *
getgrgid(gid_t gid)
{
int rval;
if (!grstart())
return NULL;
rval = grscan(1, gid, NULL, NULL);
if (!_gr_stayopen)
endgrent();
return (rval) ? &_gr_group : NULL;
}
static int
grstart(void)
{
_gr_filesdone = 0;
if (_gr_fp) {
rewind(_gr_fp);
return 1;
}
return (_gr_fp = fopen(_PATH_GROUP, "r")) ? 1 : 0;
}
void
setgrent(void)
{
(void) setgroupent(0);
}
int
setgroupent(int stayopen)
{
if (!grstart())
return 0;
_gr_stayopen = stayopen;
return 1;
}
void
endgrent(void)
{
_gr_filesdone = 0;
if (_gr_fp) {
(void)fclose(_gr_fp);
_gr_fp = NULL;
}
}
int
getgrouplist(const char *uname, gid_t agroup,
gid_t *groups, int *grpcnt)
{
struct group *grp;
int maxgroups, i, ngroups, ret;
maxgroups = *grpcnt;
ret = 0;
ngroups = 0;
/*
* install primary group
*/
if (ngroups < maxgroups)
groups[ngroups] = agroup;
else
ret = -1;
ngroups++;
/*
* Scan the group file to find additional groups.
*/
setgrent();
nextgroup:
while ((grp = getgrent()) != NULL) {
if (grp->gr_gid == agroup)
continue;
for (i = 0; grp->gr_mem[i]; i++) {
if (strcmp(grp->gr_mem[i], uname) != 0)
continue;
for (i = 0; i < MIN(ngroups, maxgroups); i++) {
if (grp->gr_gid == groups[i])
goto nextgroup;
}
if (ngroups < maxgroups)
groups[ngroups] = grp->gr_gid;
else
ret = -1;
ngroups++;
break;
}
}
endgrent();
*grpcnt = ngroups;
return ret;
}
static int
grscan(int search, gid_t gid, const char *name, const char *user)
{
if (_gr_filesdone)
return 0;
for (;;) {
if (!fgets(grline, sizeof(grline), _gr_fp)) {
if (!search)
_gr_filesdone = 1;
return 0;
}
/* skip lines that are too big */
if (!strchr(grline, '\n')) {
int ch;
while ((ch = getc(_gr_fp)) != '\n' && ch != EOF)
;
continue;
}
if (grmatchline(search, gid, name, user))
return 1;
}
/* NOTREACHED */
}
static int
grmatchline(int search, gid_t gid, const char *name, const char *user)
{
unsigned long id;
__aconst char **m;
char *cp, *bp, *ep;
/* name may be NULL if search is nonzero */
bp = grline;
_gr_group.gr_name = strsep(&bp, ":\n");
if (search && name && strcmp(_gr_group.gr_name, name))
return 0;
_gr_group.gr_passwd = strsep(&bp, ":\n");
if (!(cp = strsep(&bp, ":\n")))
return 0;
id = strtoul(cp, &ep, 10);
if (id > GID_MAX || *ep != '\0')
return 0;
_gr_group.gr_gid = (gid_t)id;
if (search && name == NULL && _gr_group.gr_gid != gid)
return 0;
cp = NULL;
if (bp == NULL)
return 0;
for (_gr_group.gr_mem = m = members;; bp++) {
if (m == &members[MAXGRP - 1])
break;
if (*bp == ',') {
if (cp) {
*bp = '\0';
*m++ = cp;
cp = NULL;
}
} else if (*bp == '\0' || *bp == '\n' || *bp == ' ') {
if (cp) {
*bp = '\0';
*m++ = cp;
}
break;
} else if (cp == NULL)
cp = bp;
}
*m = NULL;
if (user) {
for (m = members; *m; m++)
if (!strcmp(user, *m))
return 1;
return 0;
}
return 1;
}