freebsd-nq/lib/libc/gen/getgrent.c
2002-01-30 21:36:57 +00:00

705 lines
14 KiB
C

/* $NetBSD: getgrent.c,v 1.34.2.1 1999/04/27 14:10:58 perry Exp $ */
/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)getgrent.c 8.2 (Berkeley) 3/21/94";
#endif /* LIBC_SCCS and not lint */
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <errno.h>
#include <grp.h>
#include <limits.h>
#include <nsswitch.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#ifdef HESIOD
#include <hesiod.h>
#include <arpa/nameser.h>
#endif
#ifdef YP
#include <rpc/rpc.h>
#include <rpcsvc/yp_prot.h>
#include <rpcsvc/ypclnt.h>
#endif
#if defined(YP) || defined(HESIOD)
#define _GROUP_COMPAT
#endif
static FILE *_gr_fp;
static struct group _gr_group;
static int _gr_stayopen;
static int _gr_filesdone;
static void grcleanup __P((void));
static int grscan __P((int, gid_t, const char *));
static char *getline __P((void));
static int copyline __P((const char*));
static int matchline __P((int, gid_t, const char *));
static int start_gr __P((void));
/* initial size for malloc and increase steps for realloc */
#define MAXGRP 64
#define MAXLINELENGTH 256
#ifdef HESIOD
#if MAXLINELENGTH < NS_MAXLABEL + 1
#error "MAXLINELENGTH must be at least NS_MAXLABEL + 1"
#endif
#endif
static char **members; /* list of group members */
static int maxgrp; /* current length of **members */
static char *line; /* buffer for group line */
static int maxlinelength; /* current length of *line */
/*
* Lines longer than MAXLINELENGTHLIMIT will be counted as an error.
* <= 0 disable check for maximum line length
* 256K is enough for 64,000 uids
*/
#define MAXLINELENGTHLIMIT (256 * 1024)
#ifdef YP
static char *__ypcurrent, *__ypdomain;
static int __ypcurrentlen;
static int _gr_ypdone;
#endif
#ifdef HESIOD
static int _gr_hesnum;
#endif
#ifdef _GROUP_COMPAT
enum _grmode { GRMODE_NONE, GRMODE_FULL, GRMODE_NAME };
static enum _grmode __grmode;
#endif
struct group *
getgrent()
{
if ((!_gr_fp && !start_gr()) || !grscan(0, 0, NULL))
return (NULL);
return &_gr_group;
}
struct group *
getgrnam(name)
const char *name;
{
int rval;
if (!start_gr())
return NULL;
rval = grscan(1, 0, name);
if (!_gr_stayopen)
endgrent();
return (rval) ? &_gr_group : NULL;
}
struct group *
getgrgid(gid)
gid_t gid;
{
int rval;
if (!start_gr())
return NULL;
rval = grscan(1, gid, NULL);
if (!_gr_stayopen)
endgrent();
return (rval) ? &_gr_group : NULL;
}
void
grcleanup()
{
_gr_filesdone = 0;
#ifdef YP
if (__ypcurrent)
free(__ypcurrent);
__ypcurrent = NULL;
_gr_ypdone = 0;
#endif
#ifdef HESIOD
_gr_hesnum = 0;
#endif
#ifdef _GROUP_COMPAT
__grmode = GRMODE_NONE;
#endif
}
static int
start_gr()
{
grcleanup();
if (maxlinelength == 0) {
if ((line = (char *)malloc(MAXLINELENGTH)) == NULL)
return 0;
maxlinelength = MAXLINELENGTH;
}
if (maxgrp == 0) {
if ((members = (char **) malloc(sizeof(char**) *
MAXGRP)) == NULL)
return 0;
maxgrp = MAXGRP;
}
if (_gr_fp) {
rewind(_gr_fp);
return 1;
}
return (_gr_fp = fopen(_PATH_GROUP, "r")) ? 1 : 0;
}
int
setgrent(void)
{
return setgroupent(0);
}
int
setgroupent(stayopen)
int stayopen;
{
if (!start_gr())
return 0;
_gr_stayopen = stayopen;
return 1;
}
void
endgrent()
{
grcleanup();
if (_gr_fp) {
(void)fclose(_gr_fp);
_gr_fp = NULL;
}
}
static int _local_grscan __P((void *, void *, va_list));
/*ARGSUSED*/
static int
_local_grscan(rv, cb_data, ap)
void *rv;
void *cb_data;
va_list ap;
{
int search = va_arg(ap, int);
gid_t gid = va_arg(ap, gid_t);
const char *name = va_arg(ap, const char *);
if (_gr_filesdone)
return NS_NOTFOUND;
for (;;) {
if (getline() == NULL) {
if (!search)
_gr_filesdone = 1;
return NS_NOTFOUND;
}
if (matchline(search, gid, name))
return NS_SUCCESS;
}
/* NOTREACHED */
}
#ifdef HESIOD
static int _dns_grscan __P((void *, void *, va_list));
/*ARGSUSED*/
static int
_dns_grscan(rv, cb_data, ap)
void *rv;
void *cb_data;
va_list ap;
{
int search = va_arg(ap, int);
gid_t gid = va_arg(ap, gid_t);
const char *name = va_arg(ap, const char *);
char **hp;
void *context;
int r;
size_t sz;
r = NS_UNAVAIL;
if (!search && _gr_hesnum == -1)
return NS_NOTFOUND;
if (hesiod_init(&context) == -1)
return (r);
for (;;) {
if (search) {
if (name)
strlcpy(line, name, maxlinelength);
else
snprintf(line, maxlinelength, "%u",
(unsigned int)gid);
} else {
snprintf(line, maxlinelength, "group-%u", _gr_hesnum);
_gr_hesnum++;
}
hp = hesiod_resolve(context, line, "group");
if (hp == NULL) {
if (errno == ENOENT) {
if (!search)
_gr_hesnum = -1;
r = NS_NOTFOUND;
}
break;
}
/* only check first elem */
if (copyline(hp[0]) == 0)
return NS_UNAVAIL;
hesiod_free_list(context, hp);
if (matchline(search, gid, name)) {
r = NS_SUCCESS;
break;
} else if (search) {
r = NS_NOTFOUND;
break;
}
}
hesiod_end(context);
return (r);
}
#endif
#ifdef YP
static int _nis_grscan __P((void *, void *, va_list));
/*ARGSUSED*/
static int
_nis_grscan(rv, cb_data, ap)
void *rv;
void *cb_data;
va_list ap;
{
int search = va_arg(ap, int);
gid_t gid = va_arg(ap, gid_t);
const char *name = va_arg(ap, const char *);
char *key, *data;
int keylen, datalen;
int r;
size_t sz;
if(__ypdomain == NULL) {
switch (yp_get_default_domain(&__ypdomain)) {
case 0:
break;
case YPERR_RESRC:
return NS_TRYAGAIN;
default:
return NS_UNAVAIL;
}
}
if (search) { /* specific group or gid */
if (name)
strlcpy(line, name, maxlinelength);
else
snprintf(line, maxlinelength, "%u", (unsigned int)gid);
data = NULL;
r = yp_match(__ypdomain,
(name) ? "group.byname" : "group.bygid",
line, (int)strlen(line), &data, &datalen);
switch (r) {
case 0:
break;
case YPERR_KEY:
if (data)
free(data);
return NS_NOTFOUND;
default:
if (data)
free(data);
return NS_UNAVAIL;
}
data[datalen] = '\0'; /* clear trailing \n */
if (copyline(data) == 0)
return NS_UNAVAIL;
free(data);
if (matchline(search, gid, name))
return NS_SUCCESS;
else
return NS_NOTFOUND;
}
/* ! search */
if (_gr_ypdone)
return NS_NOTFOUND;
for (;;) {
data = NULL;
if(__ypcurrent) {
key = NULL;
r = yp_next(__ypdomain, "group.byname",
__ypcurrent, __ypcurrentlen,
&key, &keylen, &data, &datalen);
free(__ypcurrent);
switch (r) {
case 0:
break;
case YPERR_NOMORE:
__ypcurrent = NULL;
if (key)
free(key);
if (data)
free(data);
_gr_ypdone = 1;
return NS_NOTFOUND;
default:
if (key)
free(key);
if (data)
free(data);
return NS_UNAVAIL;
}
__ypcurrent = key;
__ypcurrentlen = keylen;
} else {
if (yp_first(__ypdomain, "group.byname",
&__ypcurrent, &__ypcurrentlen,
&data, &datalen)) {
if (data)
free(data);
return NS_UNAVAIL;
}
}
data[datalen] = '\0'; /* clear trailing \n */
if (copyline(data) == 0)
return NS_UNAVAIL;
free(data);
if (matchline(search, gid, name))
return NS_SUCCESS;
}
/* NOTREACHED */
}
#endif
#ifdef _GROUP_COMPAT
/*
* log an error if "files" or "compat" is specified in group_compat database
*/
static int _bad_grscan __P((void *, void *, va_list));
/*ARGSUSED*/
static int
_bad_grscan(rv, cb_data, ap)
void *rv;
void *cb_data;
va_list ap;
{
static int warned;
if (!warned) {
syslog(LOG_ERR,
"nsswitch.conf group_compat database can't use '%s'",
(char *)cb_data);
}
warned = 1;
return NS_UNAVAIL;
}
/*
* when a name lookup in compat mode is required, look it up in group_compat
* nsswitch database. only Hesiod and NIS is supported - it doesn't make
* sense to lookup compat names from 'files' or 'compat'
*/
static int __grscancompat __P((int, gid_t, const char *));
static int
__grscancompat(search, gid, name)
int search;
gid_t gid;
const char *name;
{
static const ns_dtab dtab[] = {
NS_FILES_CB(_bad_grscan, "files")
NS_DNS_CB(_dns_grscan, NULL)
NS_NIS_CB(_nis_grscan, NULL)
NS_COMPAT_CB(_bad_grscan, "compat")
{ 0 }
};
static const ns_src defaultnis[] = {
{ NSSRC_NIS, NS_SUCCESS },
{ 0 }
};
return (nsdispatch(NULL, dtab, NSDB_GROUP_COMPAT, "grscancompat",
defaultnis, search, gid, name));
}
#endif
static int _compat_grscan __P((void *, void *, va_list));
/*ARGSUSED*/
static int
_compat_grscan(rv, cb_data, ap)
void *rv;
void *cb_data;
va_list ap;
{
int search = va_arg(ap, int);
gid_t gid = va_arg(ap, gid_t);
const char *name = va_arg(ap, const char *);
#ifdef _GROUP_COMPAT
static char *grname = NULL;
#endif
for (;;) {
#ifdef _GROUP_COMPAT
if(__grmode != GRMODE_NONE) {
int r;
switch(__grmode) {
case GRMODE_FULL:
r = __grscancompat(search, gid, name);
if (r == NS_SUCCESS)
return r;
__grmode = GRMODE_NONE;
break;
case GRMODE_NAME:
if(grname == (char *)NULL) {
__grmode = GRMODE_NONE;
break;
}
r = __grscancompat(1, 0, grname);
free(grname);
grname = (char *)NULL;
if (r != NS_SUCCESS)
break;
if (!search)
return NS_SUCCESS;
if (name) {
if (! strcmp(_gr_group.gr_name, name))
return NS_SUCCESS;
} else {
if (_gr_group.gr_gid == gid)
return NS_SUCCESS;
}
break;
case GRMODE_NONE:
abort();
}
continue;
}
#endif /* _GROUP_COMPAT */
if (getline() == NULL)
return NS_NOTFOUND;
#ifdef _GROUP_COMPAT
if (line[0] == '+') {
char *tptr, *bp;
switch(line[1]) {
case ':':
case '\0':
case '\n':
__grmode = GRMODE_FULL;
break;
default:
__grmode = GRMODE_NAME;
bp = line;
tptr = strsep(&bp, ":\n");
grname = strdup(tptr + 1);
break;
}
continue;
}
#endif /* _GROUP_COMPAT */
if (matchline(search, gid, name))
return NS_SUCCESS;
}
/* NOTREACHED */
}
static int
grscan(search, gid, name)
int search;
gid_t gid;
const char *name;
{
int r;
static const ns_dtab dtab[] = {
NS_FILES_CB(_local_grscan, NULL)
NS_DNS_CB(_dns_grscan, NULL)
NS_NIS_CB(_nis_grscan, NULL)
NS_COMPAT_CB(_compat_grscan, NULL)
{ 0 }
};
static const ns_src compatsrc[] = {
{ NSSRC_COMPAT, NS_SUCCESS },
{ 0 }
};
r = nsdispatch(NULL, dtab, NSDB_GROUP, "grscan", compatsrc,
search, gid, name);
return (r == NS_SUCCESS) ? 1 : 0;
}
static int
matchline(search, gid, name)
int search;
gid_t gid;
const char *name;
{
unsigned long id;
char **m;
char *cp, *bp, *ep;
if (line[0] == '+')
return 0; /* sanity check to prevent recursion */
bp = line;
_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 (*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]) {
members = (char **) reallocf(members, sizeof(char **) *
(maxgrp + MAXGRP));
if (members == NULL)
return 0;
_gr_group.gr_mem = members;
m = &members[maxgrp - 1];
maxgrp += MAXGRP;
}
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;
return 1;
}
static char *
getline(void)
{
const char *cp;
tryagain:
if (fgets(line, maxlinelength, _gr_fp) == NULL)
return NULL;
if (index(line, '\n') == NULL) {
do {
if (feof(_gr_fp))
return NULL;
if (MAXLINELENGTHLIMIT > 0 &&
maxlinelength >= MAXLINELENGTHLIMIT)
return NULL;
line = (char *)reallocf(line, maxlinelength +
MAXLINELENGTH);
if (line == NULL)
return NULL;
if (fgets(line + maxlinelength - 1,
MAXLINELENGTH + 1, _gr_fp) == NULL)
return NULL;
maxlinelength += MAXLINELENGTH;
} while (index(line + maxlinelength - MAXLINELENGTH - 1,
'\n') == NULL);
}
/*
* Ignore comments: ^[ \t]*#
*/
for (cp = line; *cp != '\0'; cp++)
if (*cp != ' ' && *cp != '\t')
break;
if (*cp == '#' || *cp == '\0')
goto tryagain;
if (cp != line) /* skip white space at beginning of line */
bcopy(cp, line, strlen(cp));
return line;
}
static int
copyline(const char *src)
{
size_t sz;
sz = strlen(src);
if (sz > maxlinelength - 1) {
sz = ((sz/MAXLINELENGTH)+1) * MAXLINELENGTH;
if ((line = (char *) reallocf(line, sz)) == NULL)
return 0;
maxlinelength = sz;
}
strlcpy(line, src, maxlinelength);
return 1;
}