/*      $NetBSD: rusers_proc.c,v 1.29 2018/03/01 06:24:12 snj Exp $     */

/*-
 *  Copyright (c) 1993 John Brezak
 *  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. The name of the author may not be used to endorse or promote products
 *     derived from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR `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 AUTHOR 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/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: rusers_proc.c,v 1.29 2018/03/01 06:24:12 snj Exp $");
#endif /* not lint */

#include <sys/types.h>
#include <sys/time.h>
#include <sys/socket.h>
#include <sys/param.h>
#include <sys/stat.h>

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
#include <signal.h>
#include <syslog.h>
#include <utmp.h>

#include <rpc/rpc.h>

#include "rusers_proc.h"
#include "utmpentry.h"

#include <rpcsvc/rusers.h>      /* New version */
static size_t maxusers3 = 0;
static struct rusers_utmp *utmps;

#include <rpcsvc/rnusers.h>     /* Old version */
static size_t maxusers2 = 0;
static struct utmpidle **utmp_idlep;
static struct utmpidle *utmp_idle;

typedef char *(*rusersproc)(void *, struct svc_req *);

#ifndef _PATH_DEV
#define _PATH_DEV "/dev"
#endif


extern int from_inetd;

static int getarrays2(int);
static int getarrays3(int);
static int getidle(const char *, char *);
static int *rusers_num_svc(void *, struct svc_req *);
static utmp_array *do_names_3(int);
static struct utmpidlearr *do_names_2(int);

/* XXX */
struct utmpidlearr *rusersproc_names_2_svc(void *, struct svc_req *);
struct utmpidlearr *rusersproc_allnames_2_svc(void *, struct svc_req *);


static int
getarrays2(int ne)
{
        struct utmpidle **nutmp_idlep;
        struct utmpidle *nutmp_idle;

        /* Limit to MAXUSERS for version 2 */
        if (ne > MAXUSERS)
                ne = MAXUSERS;

        if (maxusers2 == 0) {
                nutmp_idlep = malloc(sizeof(*nutmp_idlep) * ne);
                nutmp_idle = malloc(sizeof(*nutmp_idle) * ne);
        } else {
                nutmp_idlep = realloc(utmp_idlep, sizeof(*nutmp_idlep) * ne);
                nutmp_idle = realloc(utmp_idle, sizeof(*nutmp_idle) * ne);
        }

        if (nutmp_idlep == NULL || nutmp_idle == NULL) {
                syslog(LOG_WARNING, "Cannot allocate data for %u users (%m)",
                    ne);
                free(nutmp_idlep);
                free(nutmp_idle);
                return 0;
        }

        utmp_idlep = nutmp_idlep;
        utmp_idle = nutmp_idle;
        return maxusers2 = ne;
}

static int
getarrays3(int ne)
{
        struct rusers_utmp *nutmps;

        if (maxusers3 == 0) {
                nutmps = malloc(sizeof(*nutmps) * ne);
        } else {
                nutmps = realloc(utmps, sizeof(*nutmps) * ne);
        }

        if (nutmps == NULL) {
                syslog(LOG_WARNING, "Cannot allocate data for %u users (%m)",
                    ne);
                return 0;
        }

        utmps = nutmps;
        return maxusers3 = ne;
}

static int
/*ARGUSED*/
getidle(const char *tty, char *display)
{
        struct stat st;
        char dev_name[PATH_MAX];
        time_t now;
        long idle;
        
        idle = 0;
        if (*tty == 'X') {
                long kbd_idle, mouse_idle;
#if !defined(i386)
                kbd_idle = getidle("kbd", NULL);
#else
                /*
                 * XXX Icky i386 console hack.
                 */
                kbd_idle = getidle("vga", NULL);
#endif
                mouse_idle = getidle("mouse", NULL);
                idle = (kbd_idle < mouse_idle) ? kbd_idle : mouse_idle;
        } else {
                snprintf(dev_name, sizeof dev_name, "%s/%s", _PATH_DEV, tty);
                if (stat(dev_name, &st) == -1) {
                        syslog(LOG_WARNING, "Cannot stat %s (%m)", dev_name);
                        return 0;
                }
                (void)time(&now);
#ifdef DEBUG
                printf("%s: now=%ld atime=%ld\n", dev_name,
                    (long)now, (long)st.st_atime);
#endif
                idle = now - st.st_atime;
                idle = (idle + 30) / 60; /* secs->mins */
        }
        if (idle < 0)
                idle = 0;

        return idle;
}
        
static struct utmpentry *ue = NULL;
static int nusers = 0;

static int *
/*ARGSUSED*/
rusers_num_svc(void *arg, struct svc_req *rqstp)
{
        nusers = getutentries(NULL, &ue);
        return &nusers;
}

static utmp_array *
do_names_3(int all)
{
        static utmp_array ut;
        struct utmpentry *e;
        size_t nu;
        int idle;

        nusers = getutentries(NULL, &ue);
        nusers = getarrays3(nusers);

        (void)memset(&ut, 0, sizeof(ut));
        ut.utmp_array_val = utmps;

        for (nu = 0, e = ue; e != NULL && nu < (size_t)nusers; e = e->next) {
                if ((idle = getidle(e->line, e->host)) > 0 && !all)
                        continue;
                utmps[nu].ut_type = RUSERS_USER_PROCESS;
                utmps[nu].ut_time = e->tv.tv_sec;
                utmps[nu].ut_idle = idle;
                utmps[nu].ut_line = e->line;
                utmps[nu].ut_user = e->name;
                utmps[nu].ut_host = e->host;
                nu++;
        }

        ut.utmp_array_len = nu;

        return &ut;
}

utmp_array *
/*ARGSUSED*/
rusersproc_names_3_svc(void *arg, struct svc_req *rqstp)
{

        return do_names_3(0);
}

utmp_array *
/*ARGSUSED*/
rusersproc_allnames_3_svc(void *arg, struct svc_req *rqstp)
{

        return do_names_3(1);
}

static struct utmpidlearr *
do_names_2(int all)
{
        static struct utmpidlearr ut;
        struct utmpentry *e;
        size_t nu;
        int idle;

        nusers = getutentries(NULL, &ue);
        nusers = getarrays2(nusers);
        (void)memset(&ut, 0, sizeof(ut));
        ut.uia_arr = utmp_idlep;
        ut.uia_cnt = 0;
        
        for (nu = 0, e = ue; e != NULL && nu < (size_t)nusers; e = e->next) {
                if ((idle = getidle(e->line, e->host)) > 0 && !all)
                        continue;
                utmp_idlep[nu] = &utmp_idle[nu];
                utmp_idle[nu].ui_utmp.ut_time = e->tv.tv_sec;
                utmp_idle[nu].ui_idle = idle;
                (void)strncpy(utmp_idle[nu].ui_utmp.ut_line, e->line,
                    sizeof(utmp_idle[nu].ui_utmp.ut_line));
                (void)strncpy(utmp_idle[nu].ui_utmp.ut_name, e->name,
                    sizeof(utmp_idle[nu].ui_utmp.ut_name));
                (void)strncpy(utmp_idle[nu].ui_utmp.ut_host, e->host,
                    sizeof(utmp_idle[nu].ui_utmp.ut_host));
                nu++;
        }

        ut.uia_cnt = nu;
        return &ut;
}

struct utmpidlearr *
/*ARGSUSED*/
rusersproc_names_2_svc(void *arg, struct svc_req *rqstp)
{
        return do_names_2(0);
}

struct utmpidlearr *
/*ARGSUSED*/
rusersproc_allnames_2_svc(void *arg, struct svc_req *rqstp)
{
        return do_names_2(1);
}

void
rusers_service(struct svc_req *rqstp, SVCXPRT *transp)
{
        union {
                int fill;
        } argument;
        char *result;
        xdrproc_t xdr_argument, xdr_result;
        rusersproc local;

        switch (rqstp->rq_proc) {
        case NULLPROC:
                (void)svc_sendreply(transp, (xdrproc_t)xdr_void, NULL);
                goto leave;

        case RUSERSPROC_NUM:
                xdr_argument = (xdrproc_t)xdr_void;
                xdr_result = (xdrproc_t)xdr_int;
                switch (rqstp->rq_vers) {
                case RUSERSVERS_3:
                case RUSERSVERS_IDLE:
                        local = (char *(*)(void *, struct svc_req *))
                            rusers_num_svc;
                        break;
                default:
                        svcerr_progvers(transp, RUSERSVERS_IDLE, RUSERSVERS_3);
                        goto leave;
                        /*NOTREACHED*/
                }
                break;

        case RUSERSPROC_NAMES:
                xdr_argument = (xdrproc_t)xdr_void;
                xdr_result = (xdrproc_t)xdr_utmp_array;
                switch (rqstp->rq_vers) {
                case RUSERSVERS_3:
                        local = (rusersproc)rusersproc_names_3_svc;
                        break;

                case RUSERSVERS_IDLE:
                        xdr_result = (xdrproc_t)xdr_utmpidlearr;
                        local = (rusersproc)rusersproc_names_2_svc;
                        break;

                default:
                        svcerr_progvers(transp, RUSERSVERS_IDLE, RUSERSVERS_3);
                        goto leave;
                        /*NOTREACHED*/
                }
                break;

        case RUSERSPROC_ALLNAMES:
                xdr_argument = (xdrproc_t)xdr_void;
                xdr_result = (xdrproc_t)xdr_utmp_array;
                switch (rqstp->rq_vers) {
                case RUSERSVERS_3:
                        local = (rusersproc)rusersproc_allnames_3_svc;
                        break;

                case RUSERSVERS_IDLE:
                        xdr_result = (xdrproc_t)xdr_utmpidlearr;
                        local = (rusersproc)rusersproc_allnames_2_svc;
                        break;

                default:
                        svcerr_progvers(transp, RUSERSVERS_IDLE, RUSERSVERS_3);
                        goto leave;
                        /*NOTREACHED*/
                }
                break;

        default:
                svcerr_noproc(transp);
                goto leave;
        }
        (void)memset(&argument, 0, sizeof(argument));
        if (!svc_getargs(transp, xdr_argument, (caddr_t)(void *)&argument)) {
                svcerr_decode(transp);
                goto leave;
        }
        result = (*local)(&argument, rqstp);
        if (result != NULL && !svc_sendreply(transp, xdr_result, result)) {
                svcerr_systemerr(transp);
        }
        if (!svc_freeargs(transp, xdr_argument, (caddr_t)(void *)&argument)) {
                syslog(LOG_ERR, "unable to free arguments");
                exit(1);
        }
leave:
        if (from_inetd)
                exit(0);
}