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freebsd/lib/libc/gen/getpwent.c
Bill Paul d34ef3d62b As per Justin T. Gibbs's request, agument the +@netgroup/-@netgroup
remapping mechanism in the following manner: if given an entry +@foo
and there is no netgroup named 'foo,' try searching for a regular
user group called 'foo' and build the cache using the members of
group 'foo' instead. If both a netgroup 'foo' and a user group 'foo'
exist, the 'foo' netgroup takes precedence, since we're primarily
interested in netgroup matching anyway.

This allows access control schemes based on ordinary user groups
(which are also available via NIS) rather than netgroups, since
netgroups on some systems are limited in really brain-damaged ways.
1995-03-24 05:46:47 +00:00

724 lines
17 KiB
C

/*
* Copyright (c) 1988, 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. 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[] = "@(#)getpwent.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
#include <sys/param.h>
#include <fcntl.h>
#include <db.h>
#include <syslog.h>
#include <pwd.h>
#include <utmp.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>
static struct passwd _pw_passwd; /* password structure */
static DB *_pw_db; /* password database */
static int _pw_keynum; /* key counter */
static int _pw_stayopen; /* keep fd's open */
#ifdef YP
struct _namelist {
char *name;
struct _namelist *next;
};
static struct passwd _pw_copy;
struct _pw_cache {
struct passwd pw_entry;
struct _namelist *namelist;
struct _pw_cache *next;
};
static int _pluscnt, _minuscnt;
static struct _pw_cache *_plushead = NULL, *_minushead = NULL;
static void _createcaches(), _freecaches();
static int _yp_enabled; /* set true when yp enabled */
static int _pw_stepping_yp; /* set true when stepping thru map */
#endif
static int __hashpw(), __initdb();
static int _havemaster(const char *);
static int _getyppass(struct passwd *, const char *, const char *);
static int _nextyppass(struct passwd *);
struct passwd *
getpwent()
{
DBT key;
char bf[sizeof(_pw_keynum) + 1];
int rv;
if (!_pw_db && !__initdb())
return((struct passwd *)NULL);
#ifdef YP
if(_pw_stepping_yp) {
_pw_passwd = _pw_copy;
return (_nextyppass(&_pw_passwd) ? &_pw_passwd : 0);
}
#endif
tryagain:
++_pw_keynum;
bf[0] = _PW_KEYBYNUM;
bcopy((char *)&_pw_keynum, bf + 1, sizeof(_pw_keynum));
key.data = (u_char *)bf;
key.size = sizeof(_pw_keynum) + 1;
rv = __hashpw(&key);
if(!rv) return (struct passwd *)NULL;
#ifdef YP
if (_yp_enabled) {
if(_pw_passwd.pw_name[0] == '+' || _pw_passwd.pw_name[0] == '-')
goto tryagain;
else {
_pw_copy = _pw_passwd;
return (_nextyppass(&_pw_passwd) ? &_pw_passwd : 0);
}
}
#else
/* Ignore YP password file entries when YP is disabled. */
if(_pw_passwd.pw_name[0] == '+') {
goto tryagain;
}
#endif
return(&_pw_passwd);
}
struct passwd *
getpwnam(name)
const char *name;
{
DBT key;
int len, rval;
char bf[UT_NAMESIZE + 2];
if (!_pw_db && !__initdb())
return((struct passwd *)NULL);
bf[0] = _PW_KEYBYNAME;
len = strlen(name);
bcopy(name, bf + 1, MIN(len, UT_NAMESIZE));
key.data = (u_char *)bf;
key.size = len + 1;
rval = __hashpw(&key);
#ifdef YP
if (!rval && _yp_enabled)
rval = _getyppass(&_pw_passwd, name, "passwd.byname");
#endif
/*
* Prevent login attempts when YP is not enabled but YP entries
* are in /etc/master.passwd.
*/
if (rval && _pw_passwd.pw_name[0] == '+') rval = 0;
endpwent();
return(rval ? &_pw_passwd : (struct passwd *)NULL);
}
struct passwd *
#ifdef __STDC__
getpwuid(uid_t uid)
#else
getpwuid(uid)
int uid;
#endif
{
DBT key;
int keyuid, rval;
char bf[sizeof(keyuid) + 1];
if (!_pw_db && !__initdb())
return((struct passwd *)NULL);
bf[0] = _PW_KEYBYUID;
keyuid = uid;
bcopy(&keyuid, bf + 1, sizeof(keyuid));
key.data = (u_char *)bf;
key.size = sizeof(keyuid) + 1;
rval = __hashpw(&key);
#ifdef YP
if (!rval && _yp_enabled) {
char ypbuf[16]; /* big enough for 32-bit uids and then some */
snprintf(ypbuf, sizeof ypbuf, "%u", (unsigned)uid);
rval = _getyppass(&_pw_passwd, ypbuf, "passwd.byuid");
}
#endif
endpwent();
return(rval ? &_pw_passwd : (struct passwd *)NULL);
}
int
setpassent(stayopen)
int stayopen;
{
_pw_keynum = 0;
#ifdef YP
_pw_stepping_yp = 0;
#endif
_pw_stayopen = stayopen;
return(1);
}
int
setpwent()
{
_pw_keynum = 0;
#ifdef YP
_pw_stepping_yp = 0;
#endif
_pw_stayopen = 0;
return(1);
}
void
endpwent()
{
_pw_keynum = 0;
#ifdef YP
_pw_stepping_yp = 0;
#endif
if (_pw_db) {
(void)(_pw_db->close)(_pw_db);
_pw_db = (DB *)NULL;
#ifdef YP
_freecaches();
#endif
}
}
static
__initdb()
{
static int warned;
char *p;
p = (geteuid()) ? _PATH_MP_DB : _PATH_SMP_DB;
_pw_db = dbopen(p, O_RDONLY, 0, DB_HASH, NULL);
if (_pw_db) {
#ifdef YP
DBT key, data;
char buf[] = { _PW_KEYYPENABLED };
key.data = buf;
key.size = 1;
if ((_pw_db->get)(_pw_db, &key, &data, 0)) {
_yp_enabled = 0;
} else {
_yp_enabled = (int)*((char *)data.data) - 2;
_createcaches();
}
#endif
return(1);
}
if (!warned)
syslog(LOG_ERR, "%s: %m", p);
return(0);
}
static
__hashpw(key)
DBT *key;
{
register char *p, *t;
static u_int max;
static char *line;
DBT data;
if ((_pw_db->get)(_pw_db, key, &data, 0))
return(0);
p = (char *)data.data;
if (data.size > max && !(line = realloc(line, max += 1024)))
return(0);
t = line;
#define EXPAND(e) e = t; while (*t++ = *p++);
EXPAND(_pw_passwd.pw_name);
EXPAND(_pw_passwd.pw_passwd);
bcopy(p, (char *)&_pw_passwd.pw_uid, sizeof(int));
p += sizeof(int);
bcopy(p, (char *)&_pw_passwd.pw_gid, sizeof(int));
p += sizeof(int);
bcopy(p, (char *)&_pw_passwd.pw_change, sizeof(time_t));
p += sizeof(time_t);
EXPAND(_pw_passwd.pw_class);
EXPAND(_pw_passwd.pw_gecos);
EXPAND(_pw_passwd.pw_dir);
EXPAND(_pw_passwd.pw_shell);
bcopy(p, (char *)&_pw_passwd.pw_expire, sizeof(time_t));
p += sizeof(time_t);
bcopy(p, (char *)&_pw_passwd.pw_fields, sizeof _pw_passwd.pw_fields);
p += sizeof _pw_passwd.pw_fields;
return(1);
}
#ifdef YP
/*
* Build special +@netgroup and -@netgroup caches. We also handle ordinary
* +user/-user entries, *and* +@group/-@group entries, which are special
* cases of the +@netgroup/-@netgroup substitutions: if we can't find
* netgroup 'foo', we look for a regular user group called 'foo' and
* match against that instead. The netgroup takes precedence since the
* +group/-group support is basically just a hack to make Justin T. Gibbs
* happy. :) Sorting out all the funny business here lets us have a
* yp_enabled flag with a simple on or off value instead of the somewhat
* bogus setup we had before.
*
* We cache everything here in one shot so that we only have to scan
* each netgroup/group once. The alternative is to use innetgr() inside the
* NIS lookup functions, which would make retrieving the whole password
* database though getpwent() very slow. +user/-user entries are treated
* like @groups/@netgroups with only one member.
*/
#include <grp.h>
static void
_createcaches()
{
DBT key, data;
int i;
char bf[UT_NAMESIZE + 2];
char entry[UT_NAMESIZE];
struct _pw_cache *p, *m;
struct _namelist *n, *namehead;
char *user, *host, *domain;
struct group *grp;
/*
* Assume that the database has already been initialized
* but be paranoid and check that YP is in fact enabled.
*/
if (!_yp_enabled)
return;
/*
* For the plus list, we have to store both the linked list of
* names and the +entries from the password database so we can
* do the substitution later if we find a match.
*/
bf[0] = _PW_KEYPLUSCNT;
key.data = (u_char*)bf;
key.size = 1;
if (!(_pw_db->get)(_pw_db, &key, &data, 0)) {
_pluscnt = (int)*((char *)data.data);
for (i = 0; i < _pluscnt; i++) {
bf[0] = _PW_KEYPLUSBYNUM;
bcopy(&i, bf + 1, sizeof(i) + 1);
key.size = (sizeof(i)) + 1;
if (__hashpw(&key)) {
p = (struct _pw_cache *)malloc(sizeof (struct _pw_cache));
if (strlen(_pw_passwd.pw_name) > 2 && _pw_passwd.pw_name[1] == '@') {
setnetgrent(_pw_passwd.pw_name+2);
namehead = NULL;
while(getnetgrent(&host, &user, &domain)) {
n = (struct _namelist *)malloc(sizeof (struct _namelist));
n->name = strdup(user);
n->next = namehead;
namehead = n;
}
/*
* If netgroup 'foo' doesn't exist,
* try group 'foo' instead.
*/
if (namehead == NULL && (grp = getgrnam(_pw_passwd.pw_name+2)) != NULL) {
while(*grp->gr_mem) {
n = (struct _namelist *)malloc(sizeof (struct _namelist));
n->name = strdup(*grp->gr_mem);
n->next = namehead;
namehead = n;
grp->gr_mem++;
}
}
} else {
if (_pw_passwd.pw_name[1] != '@') {
namehead = (struct _namelist *)malloc(sizeof (struct _namelist));
namehead->name = strdup(_pw_passwd.pw_name+1);
namehead->next = NULL;
}
}
p->namelist = namehead;
p->pw_entry.pw_name = strdup(_pw_passwd.pw_name);
p->pw_entry.pw_passwd = strdup(_pw_passwd.pw_passwd);
p->pw_entry.pw_uid = _pw_passwd.pw_uid;
p->pw_entry.pw_gid = _pw_passwd.pw_gid;
p->pw_entry.pw_expire = _pw_passwd.pw_expire;
p->pw_entry.pw_change = _pw_passwd.pw_change;
p->pw_entry.pw_class = strdup(_pw_passwd.pw_class);
p->pw_entry.pw_gecos = strdup(_pw_passwd.pw_gecos);
p->pw_entry.pw_dir = strdup(_pw_passwd.pw_dir);
p->pw_entry.pw_shell = strdup(_pw_passwd.pw_shell);
p->pw_entry.pw_fields = _pw_passwd.pw_fields;
p->next = _plushead;
_plushead = p;
}
}
}
/*
* All we need for the minuslist is the usernames.
* The actual -entries data can be ignored since no substitution
* will be done: anybody on the minus list is treated like a
* non-person.
*/
bf[0] = _PW_KEYMINUSCNT;
key.data = (u_char*)bf;
key.size = 1;
if (!(_pw_db->get)(_pw_db, &key, &data, 0)) {
_minuscnt = (int)*((char *)data.data);
for (i = 0; i < _minuscnt; i++) {
bf[0] = _PW_KEYMINUSBYNUM;
bcopy(&i, bf + 1, sizeof(i) + 1);
key.size = (sizeof(i)) + 1;
if (__hashpw(&key)) {
m = (struct _pw_cache *)malloc(sizeof (struct _pw_cache));
if (strlen (_pw_passwd.pw_name) > 2 && _pw_passwd.pw_name[1] == '@') {
namehead = NULL;
setnetgrent(_pw_passwd.pw_name+2);
while(getnetgrent(&host, &user, &domain)) {
n = (struct _namelist *)malloc(sizeof (struct _namelist));
n->name = strdup(user);
n->next = namehead;
namehead = n;
}
/*
* If netgroup 'foo' doesn't exist,
* try group 'foo' instead.
*/
if (namehead == NULL && (grp = getgrnam(_pw_passwd.pw_name+2)) != NULL) {
while(*grp->gr_mem) {
n = (struct _namelist *)malloc(sizeof (struct _namelist));
n->name = strdup(*grp->gr_mem);
n->next = namehead;
namehead = n;
grp->gr_mem++;
}
}
} else {
if (_pw_passwd.pw_name[1] != '@') {
namehead = (struct _namelist *)malloc(sizeof (struct _namelist));
namehead->name = strdup(_pw_passwd.pw_name+1);
namehead->next = NULL;
}
}
m->namelist = namehead;
m->next = _minushead;
_minushead = m;
}
}
}
}
/*
* Free the +@netgroup/-@netgroup caches. Should be called
* from endpwent(). We have to blow away both the list of
* netgroups and the attached linked lists of usernames.
*/
static void
_freecaches()
{
struct _pw_cache *p, *m;
struct _namelist *n;
while (_plushead) {
while(_plushead->namelist) {
n = _plushead->namelist->next;
free(_plushead->namelist);
_plushead->namelist = n;
}
p = _plushead->next;
free(_plushead);
_plushead = p;
}
while(_minushead) {
while(_minushead->namelist) {
n = _minushead->namelist->next;
free(_minushead->namelist);
_minushead->namelist = n;
}
m = _minushead->next;
free(_minushead);
_minushead = m;
}
_pluscnt = _minuscnt = 0;
}
static void
_pw_breakout_yp(struct passwd *pw, char *result, int master)
{
char *s;
s = strsep(&result, ":"); /* name */
if(!(pw->pw_fields & _PWF_NAME) || (pw->pw_name[0] == '+')) {
pw->pw_name = s;
pw->pw_fields |= _PWF_NAME;
}
s = strsep(&result, ":"); /* password */
if(!(pw->pw_fields & _PWF_PASSWD)) {
pw->pw_passwd = s;
pw->pw_fields |= _PWF_PASSWD;
}
s = strsep(&result, ":"); /* uid */
if(!(pw->pw_fields & _PWF_UID)) {
pw->pw_uid = atoi(s);
pw->pw_fields |= _PWF_UID;
}
s = strsep(&result, ":"); /* gid */
if(!(pw->pw_fields & _PWF_GID)) {
pw->pw_gid = atoi(s);
pw->pw_fields |= _PWF_GID;
}
if (master) {
s = strsep(&result, ":"); /* class */
if(!(pw->pw_fields & _PWF_CLASS)) {
pw->pw_class = s;
pw->pw_fields |= _PWF_CLASS;
}
s = strsep(&result, ":"); /* change */
if(!(pw->pw_fields & _PWF_CHANGE)) {
pw->pw_change = atol(s);
pw->pw_fields |= _PWF_CHANGE;
}
s = strsep(&result, ":"); /* expire */
if(!(pw->pw_fields & _PWF_EXPIRE)) {
pw->pw_expire = atol(s);
pw->pw_fields |= _PWF_EXPIRE;
}
}
s = strsep(&result, ":"); /* gecos */
if(!(pw->pw_fields & _PWF_GECOS)) {
pw->pw_gecos = s;
pw->pw_fields |= _PWF_GECOS;
}
s = strsep(&result, ":"); /* dir */
if(!(pw->pw_fields & _PWF_DIR)) {
pw->pw_dir = s;
pw->pw_fields |= _PWF_DIR;
}
s = strsep(&result, ":"); /* shell */
if(!(pw->pw_fields & _PWF_SHELL)) {
pw->pw_shell = s;
pw->pw_fields |= _PWF_SHELL;
}
}
static char *_pw_yp_domain;
static int
_havemaster(const char *_pw_yp_domain)
{
char *result;
static char *key;
int resultlen;
static int keylen;
if (yp_first(_pw_yp_domain, "master.passwd.byname",
&key, &keylen, &result, &resultlen))
return 0;
return 1;
}
static int
_getyppass(struct passwd *pw, const char *name, const char *map)
{
char *result, *s;
static char resultbuf[1024];
int resultlen;
char mastermap[1024];
int gotmaster = 0;
struct _pw_cache *m, *p;
struct _namelist *n;
if(!_pw_yp_domain) {
if(yp_get_default_domain(&_pw_yp_domain))
return 0;
}
sprintf(mastermap,"%s",map);
/* Don't even bother with this if we aren't root. */
if (!geteuid())
if (_havemaster(_pw_yp_domain)) {
sprintf(mastermap,"master.%s", map);
gotmaster++;
}
if(yp_match(_pw_yp_domain, &mastermap, name, strlen(name),
&result, &resultlen))
return 0;
s = strchr(result, '\n');
if(s) *s = '\0';
if(resultlen >= sizeof resultbuf) return 0;
strcpy(resultbuf, result);
s = strsep(&result,":");
_pw_passwd.pw_fields = 0;
if (_minuscnt && _minushead) {
m = _minushead;
while (m) {
n = m->namelist;
while (n) {
if (!strcmp(n->name, s) || *n->name == '\0') {
free(result);
return (0);
}
n = n->next;
}
m = m->next;
}
}
if (_pluscnt && _plushead) {
p = _plushead;
while (p) {
n = p->namelist;
while (n) {
if (!strcmp(n->name, s) || *n->name == '\0')
bcopy((char *)&p->pw_entry,
(char *)&_pw_passwd, sizeof(p->pw_entry));
n = n->next;
}
p = p->next;
}
}
free(result);
result = resultbuf;
_pw_breakout_yp(pw, resultbuf, gotmaster);
return 1;
}
static int
_nextyppass(struct passwd *pw)
{
static char *key, *s;
static int keylen;
char *lastkey, *result;
static char resultbuf[1024];
int resultlen;
int rv;
char *map = "passwd.byname";
int gotmaster = 0;
struct _pw_cache *m, *p;
struct _namelist *n;
if(!_pw_yp_domain) {
if(yp_get_default_domain(&_pw_yp_domain))
return 0;
}
/* Don't even bother with this if we aren't root. */
if (!geteuid())
if(_havemaster(_pw_yp_domain)) {
map = "master.passwd.byname";
gotmaster++;
}
if(!_pw_stepping_yp) {
if(key) free(key);
rv = yp_first(_pw_yp_domain, map,
&key, &keylen, &result, &resultlen);
if(rv) {
return 0;
}
_pw_stepping_yp = 1;
goto unpack;
} else {
tryagain:
lastkey = key;
rv = yp_next(_pw_yp_domain, map, key, keylen,
&key, &keylen, &result, &resultlen);
free(lastkey);
unpack:
if(rv) {
_pw_stepping_yp = 0;
return 0;
}
if(resultlen > sizeof(resultbuf)) {
free(result);
goto tryagain;
}
strcpy(resultbuf, result);
s = strsep(&result,":");
_pw_passwd.pw_fields = 0;
if (_minuscnt && _minushead) {
m = _minushead;
while (m) {
n = m->namelist;
while (n) {
if (!strcmp(n->name, s) || *n->name == '\0') {
free(result);
goto tryagain;
}
n = n->next;
}
m = m->next;
}
}
if (_pluscnt && _plushead) {
p = _plushead;
while (p) {
n = p->namelist;
while (n) {
if (!strcmp(n->name, s) || *n->name == '\0')
bcopy((char *)&p->pw_entry,
(char*)&_pw_passwd, sizeof(p->pw_entry));
n = n->next;
}
p = p->next;
}
}
free(result);
if(result = strchr(resultbuf, '\n')) *result = '\0';
_pw_breakout_yp(pw, resultbuf, gotmaster);
}
return 1;
}
#endif /* YP */