/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 2009, Sun Microsystems, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions are met:
 * - Redistributions of source code must retain the above copyright notice, 
 *   this list of conditions and the following disclaimer.
 * - 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.
 * - Neither the name of Sun Microsystems, Inc. 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 COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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.
 */

/*
 * netname utility routines convert from unix names to network names and
 * vice-versa This module is operating system dependent! What we define here
 * will work with any unix system that has adopted the sun NIS domain
 * architecture.
 */
#include "namespace.h"
#include <sys/param.h>
#include <rpc/rpc.h>
#include <rpc/rpc_com.h>
#ifdef YP
#include <rpcsvc/yp_prot.h>
#include <rpcsvc/ypclnt.h>
#endif
#include <ctype.h>
#include <stdio.h>
#include <grp.h>
#include <pwd.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include "un-namespace.h"

static char    *OPSYS = "unix";
#ifdef YP
static char    *NETID = "netid.byname";
#endif
static char    *NETIDFILE = "/etc/netid";

static int getnetid( char *, char * );
static int _getgroups( char *, gid_t [NGRPS] );

/*
 * Convert network-name into unix credential
 */
int
netname2user(char netname[MAXNETNAMELEN + 1], uid_t *uidp, gid_t *gidp,
    int *gidlenp, gid_t *gidlist)
{
        char           *p;
        int             gidlen;
        uid_t           uid;
        long            luid;
        struct passwd  *pwd;
        char            val[1024];
        char           *val1, *val2;
        char           *domain;
        int             vallen;
        int             err;

        if (getnetid(netname, val)) {
                char *res = val;

                p = strsep(&res, ":");
                if (p == NULL)
                        return (0);
                *uidp = (uid_t) atol(p);
                p = strsep(&res, "\n,");
                if (p == NULL) {
                        return (0);
                }
                *gidp = (gid_t) atol(p);
                for (gidlen = 0; gidlen < NGRPS; gidlen++) {
                        p = strsep(&res, "\n,");
                        if (p == NULL)
                                break;
                        gidlist[gidlen] = (gid_t) atol(p);
                }
                *gidlenp = gidlen;

                return (1);
        }
        val1 = strchr(netname, '.');
        if (val1 == NULL)
                return (0);
        if (strncmp(netname, OPSYS, (val1-netname)))
                return (0);
        val1++;
        val2 = strchr(val1, '@');
        if (val2 == NULL)
                return (0);
        vallen = val2 - val1;
        if (vallen > (1024 - 1))
                vallen = 1024 - 1;
        (void) strncpy(val, val1, 1024);
        val[vallen] = 0;

        err = __rpc_get_default_domain(&domain);        /* change to rpc */
        if (err)
                return (0);

        if (strcmp(val2 + 1, domain))
                return (0);     /* wrong domain */

        if (sscanf(val, "%ld", &luid) != 1)
                return (0);
        uid = luid;

        /* use initgroups method */
        pwd = getpwuid(uid);
        if (pwd == NULL)
                return (0);
        *uidp = pwd->pw_uid;
        *gidp = pwd->pw_gid;
        *gidlenp = _getgroups(pwd->pw_name, gidlist);
        return (1);
}

/*
 * initgroups
 */

static int
_getgroups(char *uname, gid_t groups[NGRPS])
{
        gid_t           ngroups = 0;
        struct group *grp;
        int    i;
        int    j;
        int             filter;

        setgrent();
        while ((grp = getgrent())) {
                for (i = 0; grp->gr_mem[i]; i++)
                        if (!strcmp(grp->gr_mem[i], uname)) {
                                if (ngroups == NGRPS) {
#ifdef DEBUG
                                        fprintf(stderr,
                                "initgroups: %s is in too many groups\n", uname);
#endif
                                        goto toomany;
                                }
                                /* filter out duplicate group entries */
                                filter = 0;
                                for (j = 0; j < ngroups; j++)
                                        if (groups[j] == grp->gr_gid) {
                                                filter++;
                                                break;
                                        }
                                if (!filter)
                                        groups[ngroups++] = grp->gr_gid;
                        }
        }
toomany:
        endgrent();
        return (ngroups);
}

/*
 * Convert network-name to hostname
 */
int
netname2host(char netname[MAXNETNAMELEN + 1], char *hostname, int hostlen)
{
        int             err;
        char            valbuf[1024];
        char           *val;
        char           *val2;
        int             vallen;
        char           *domain;

        if (getnetid(netname, valbuf)) {
                val = valbuf;
                if ((*val == '0') && (val[1] == ':')) {
                        (void) strncpy(hostname, val + 2, hostlen);
                        return (1);
                }
        }
        val = strchr(netname, '.');
        if (val == NULL)
                return (0);
        if (strncmp(netname, OPSYS, (val - netname)))
                return (0);
        val++;
        val2 = strchr(val, '@');
        if (val2 == NULL)
                return (0);
        vallen = val2 - val;
        if (vallen > (hostlen - 1))
                vallen = hostlen - 1;
        (void) strncpy(hostname, val, vallen);
        hostname[vallen] = 0;

        err = __rpc_get_default_domain(&domain);        /* change to rpc */
        if (err)
                return (0);

        if (strcmp(val2 + 1, domain))
                return (0);     /* wrong domain */
        else
                return (1);
}

/*
 * reads the file /etc/netid looking for a + to optionally go to the
 * network information service.
 */
int
getnetid(char *key, char *ret)
{
        char            buf[1024];      /* big enough */
        char           *res;
        char           *mkey;
        char           *mval;
        FILE           *fd;
#ifdef YP
        char           *domain;
        int             err;
        char           *lookup;
        int             len;
#endif
        int rv;

        rv = 0;

        fd = fopen(NETIDFILE, "r");
        if (fd == NULL) {
#ifdef YP
                res = "+";
                goto getnetidyp;
#else
                return (0);
#endif
        }
        while (fd != NULL) {
                res = fgets(buf, sizeof(buf), fd);
                if (res == NULL) {
                        rv = 0;
                        goto done;
                }
                if (res[0] == '#')
                        continue;
                else if (res[0] == '+') {
#ifdef YP
        getnetidyp:
                        err = yp_get_default_domain(&domain);
                        if (err) {
                                continue;
                        }
                        lookup = NULL;
                        err = yp_match(domain, NETID, key,
                                strlen(key), &lookup, &len);
                        if (err) {
#ifdef DEBUG
                                fprintf(stderr, "match failed error %d\n", err);
#endif
                                continue;
                        }
                        lookup[len] = 0;
                        strcpy(ret, lookup);
                        free(lookup);
                        rv = 2;
                        goto done;
#else   /* YP */
#ifdef DEBUG
                        fprintf(stderr,
"Bad record in %s '+' -- NIS not supported in this library copy\n",
                                NETIDFILE);
#endif
                        continue;
#endif  /* YP */
                } else {
                        mkey = strsep(&res, "\t ");
                        if (mkey == NULL) {
                                fprintf(stderr,
                "Bad record in %s -- %s", NETIDFILE, buf);
                                continue;
                        }
                        do {
                                mval = strsep(&res, " \t#\n");
                        } while (mval != NULL && !*mval);
                        if (mval == NULL) {
                                fprintf(stderr,
                "Bad record in %s val problem - %s", NETIDFILE, buf);
                                continue;
                        }
                        if (strcmp(mkey, key) == 0) {
                                strcpy(ret, mval);
                                rv = 1;
                                goto done;
                        }
                }
        }

done:
        if (fd != NULL)
                fclose(fd);
        return (rv);
}