/*      $NetBSD: getid.c,v 1.10 2014/10/27 21:46:45 christos Exp $      */
/*      from: NetBSD: getpwent.c,v 1.48 2000/10/03 03:22:26 enami Exp */
/*      from: NetBSD: getgrent.c,v 1.41 2002/01/12 23:51:30 lukem Exp */

/*
 * Copyright (c) 1987, 1988, 1989, 1993, 1994, 1995
 *      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.
 */

/*-
 * Copyright (c) 2002 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Luke Mewburn of Wasabi Systems.
 *
 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

#include <sys/param.h>

#include <grp.h>
#include <limits.h>
#include <pwd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

#include "extern.h"

static  struct group *  gi_getgrnam(const char *);
static  struct group *  gi_getgrgid(gid_t);
static  int             gi_setgroupent(int);
static  void            gi_endgrent(void);
static  int             grstart(void);
static  int             grscan(int, gid_t, const char *);
static  int             grmatchline(int, gid_t, const char *);

static  struct passwd * gi_getpwnam(const char *);
static  struct passwd * gi_getpwuid(uid_t);
static  int             gi_setpassent(int);
static  void            gi_endpwent(void);
static  int             pwstart(void);
static  int             pwscan(int, uid_t, const char *);
static  int             pwmatchline(int, uid_t, const char *);

#define MAXGRP          200
#define MAXLINELENGTH   1024

static  FILE            *_gr_fp;
static  struct group    _gr_group;
static  int             _gr_stayopen;
static  int             _gr_filesdone;
static  FILE            *_pw_fp;
static  struct passwd   _pw_passwd;     /* password structure */
static  int             _pw_stayopen;   /* keep fd's open */
static  int             _pw_filesdone;

static  char            grfile[MAXPATHLEN];
static  char            pwfile[MAXPATHLEN];

static  char            *members[MAXGRP];
static  char            grline[MAXLINELENGTH];
static  char            pwline[MAXLINELENGTH];

int
setup_getid(const char *dir)
{
        if (dir == NULL)
                return (0);

                                /* close existing databases */
        gi_endgrent();
        gi_endpwent();

                                /* build paths to new databases */
        snprintf(grfile, sizeof(grfile), "%s/group", dir);
        snprintf(pwfile, sizeof(pwfile), "%s/master.passwd", dir);

                                /* try to open new databases */
        if (!grstart() || !pwstart())
                return (0);

                                /* switch pwcache(3) lookup functions */
        if (pwcache_groupdb(gi_setgroupent, gi_endgrent,
                            gi_getgrnam, gi_getgrgid) == -1
            || pwcache_userdb(gi_setpassent, gi_endpwent,
                            gi_getpwnam, gi_getpwuid) == -1)
                return (0);

        return (1);
}


/*
 * group lookup functions
 */

static struct group *
gi_getgrnam(const char *name)
{
        int rval;

        if (!grstart())
                return NULL;
        rval = grscan(1, 0, name);
        if (!_gr_stayopen)
                endgrent();
        return (rval) ? &_gr_group : NULL;
}

static struct group *
gi_getgrgid(gid_t gid)
{
        int rval;

        if (!grstart())
                return NULL;
        rval = grscan(1, gid, NULL);
        if (!_gr_stayopen)
                endgrent();
        return (rval) ? &_gr_group : NULL;
}

static int
gi_setgroupent(int stayopen)
{

        if (!grstart())
                return 0;
        _gr_stayopen = stayopen;
        return 1;
}

static void
gi_endgrent(void)
{

        _gr_filesdone = 0;
        if (_gr_fp) {
                (void)fclose(_gr_fp);
                _gr_fp = NULL;
        }
}

static int
grstart(void)
{

        _gr_filesdone = 0;
        if (_gr_fp) {
                rewind(_gr_fp);
                return 1;
        }
        if (grfile[0] == '\0')                  /* sanity check */
                return 0;

        _gr_fp = fopen(grfile, "r");
        if (_gr_fp != NULL)
                return 1;
        warn("Can't open `%s'", grfile);
        return 0;
}


static int
grscan(int search, gid_t gid, const char *name)
{

        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;
                }
                /* skip comments */
                if (grline[0] == '#')
                        continue;
                if (grmatchline(search, gid, name))
                        return 1;
        }
        /* NOTREACHED */
}

static int
grmatchline(int search, gid_t gid, const char *name)
{
        unsigned long   id;
        char            **m;
        char            *cp, *bp, *ep;

        /* name may be NULL if search is nonzero */

        bp = grline;
        memset(&_gr_group, 0, sizeof(_gr_group));
        _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;
        return 1;
}


/*
 * user lookup functions
 */

static struct passwd *
gi_getpwnam(const char *name)
{
        int rval;

        if (!pwstart())
                return NULL;
        rval = pwscan(1, 0, name);
        if (!_pw_stayopen)
                endpwent();
        return (rval) ? &_pw_passwd : NULL;
}

static struct passwd *
gi_getpwuid(uid_t uid)
{
        int rval;

        if (!pwstart())
                return NULL;
        rval = pwscan(1, uid, NULL);
        if (!_pw_stayopen)
                endpwent();
        return (rval) ? &_pw_passwd : NULL;
}

static int
gi_setpassent(int stayopen)
{

        if (!pwstart())
                return 0;
        _pw_stayopen = stayopen;
        return 1;
}

static void
gi_endpwent(void)
{

        _pw_filesdone = 0;
        if (_pw_fp) {
                (void)fclose(_pw_fp);
                _pw_fp = NULL;
        }
}

static int
pwstart(void)
{

        _pw_filesdone = 0;
        if (_pw_fp) {
                rewind(_pw_fp);
                return 1;
        }
        if (pwfile[0] == '\0')                  /* sanity check */
                return 0;
        _pw_fp = fopen(pwfile, "r");
        if (_pw_fp != NULL)
                return 1;
        warn("Can't open `%s'", pwfile);
        return 0;
}


static int
pwscan(int search, uid_t uid, const char *name)
{

        if (_pw_filesdone)
                return 0;
        for (;;) {
                if (!fgets(pwline, sizeof(pwline), _pw_fp)) {
                        if (!search)
                                _pw_filesdone = 1;
                        return 0;
                }
                /* skip lines that are too big */
                if (!strchr(pwline, '\n')) {
                        int ch;

                        while ((ch = getc(_pw_fp)) != '\n' && ch != EOF)
                                ;
                        continue;
                }
                /* skip comments */
                if (pwline[0] == '#')
                        continue;
                if (pwmatchline(search, uid, name))
                        return 1;
        }
        /* NOTREACHED */
}

static int
pwmatchline(int search, uid_t uid, const char *name)
{
        unsigned long   id;
        char            *cp, *bp, *ep;

        /* name may be NULL if search is nonzero */

        bp = pwline;
        memset(&_pw_passwd, 0, sizeof(_pw_passwd));
        _pw_passwd.pw_name = strsep(&bp, ":\n");                /* name */
        if (search && name && strcmp(_pw_passwd.pw_name, name))
                return 0;

        _pw_passwd.pw_passwd = strsep(&bp, ":\n");              /* passwd */

        if (!(cp = strsep(&bp, ":\n")))                         /* uid */
                return 0;
        id = strtoul(cp, &ep, 10);
        if (id > UID_MAX || *ep != '\0')
                return 0;
        _pw_passwd.pw_uid = (uid_t)id;
        if (search && name == NULL && _pw_passwd.pw_uid != uid)
                return 0;

        if (!(cp = strsep(&bp, ":\n")))                         /* gid */
                return 0;
        id = strtoul(cp, &ep, 10);
        if (id > GID_MAX || *ep != '\0')
                return 0;
        _pw_passwd.pw_gid = (gid_t)id;

        if (!(ep = strsep(&bp, ":")))                           /* class */
                return 0;
        if (!(ep = strsep(&bp, ":")))                           /* change */
                return 0;
        if (!(ep = strsep(&bp, ":")))                           /* expire */
                return 0;

        if (!(_pw_passwd.pw_gecos = strsep(&bp, ":\n")))        /* gecos */
                return 0;
        if (!(_pw_passwd.pw_dir = strsep(&bp, ":\n")))          /* directory */
                return 0;
        if (!(_pw_passwd.pw_shell = strsep(&bp, ":\n")))        /* shell */
                return 0;

        if (strchr(bp, ':') != NULL)
                return 0;

        return 1;
}