usr/src/lib/libc/gen/getpwent.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 */
static int __hashpw(), __initdb();

struct passwd *
getpwent()
{
        DBT key;
        char bf[sizeof(_pw_keynum) + 1];

        if (!_pw_db && !__initdb())
                return((struct passwd *)NULL);

        ++_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;
        return(__hashpw(&key) ? &_pw_passwd : (struct passwd *)NULL);
}

struct passwd *
getpwnam(name)
        const char *name;
{
        DBT key;
        int len, rval;
        char bf[UT_NAMESIZE + 1];

        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);

        if (!_pw_stayopen) {
                (void)(_pw_db->close)(_pw_db);
                _pw_db = (DB *)NULL;
        }
        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);

        if (!_pw_stayopen) {
                (void)(_pw_db->close)(_pw_db);
                _pw_db = (DB *)NULL;
        }
        return(rval ? &_pw_passwd : (struct passwd *)NULL);
}

int
setpassent(stayopen)
        int stayopen;
{
        _pw_keynum = 0;
        _pw_stayopen = stayopen;
        return(1);
}

int
setpwent()
{
        _pw_keynum = 0;
        _pw_stayopen = 0;
        return(1);
}

void
endpwent()
{
        _pw_keynum = 0;
        if (_pw_db) {
                (void)(_pw_db->close)(_pw_db);
                _pw_db = (DB *)NULL;
        }
}

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)
                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);
        return(1);
}