/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
 * Copyright 2018 Nexenta Systems, Inc.  All rights reserved.
 * Copyright 2022 RackTop Systems, Inc.
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioccom.h>
#include <sys/corectl.h>
#include <stdio.h>
#include <string.h>
#include <strings.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdarg.h>
#include <fcntl.h>
#include <wait.h>
#include <signal.h>
#include <atomic.h>
#include <libscf.h>
#include <limits.h>
#include <priv_utils.h>
#include <door.h>
#include <errno.h>
#include <pthread.h>
#include <time.h>
#include <libscf.h>
#include <zone.h>
#include <libgen.h>
#include <pwd.h>
#include <grp.h>

#include <smbsrv/smb_door.h>
#include <smbsrv/smb_ioctl.h>
#include <smbsrv/string.h>
#include <smbsrv/libsmb.h>
#include <smbsrv/libsmbns.h>
#include <smbsrv/libmlsvc.h>
#include "smbd.h"

#define SECSPERMIN                      60
#define SMBD_ONLINE_WAIT_INTERVAL       10
#define SMBD_REFRESH_INTERVAL           10
#define SMB_DBDIR "/var/smb"

static int smbd_daemonize_init(void);
static void smbd_daemonize_fini(int, int);
static int smb_init_daemon_priv(int, uid_t, gid_t);

static int smbd_kernel_bind(void);
static void smbd_kernel_unbind(void);
static int smbd_already_running(void);

static int smbd_service_init(void);
static void smbd_service_fini(void);

static int smbd_setup_options(int argc, char *argv[]);
static void smbd_usage(FILE *fp);

static int32_t smbd_gmtoff(void);
static void smbd_localtime_init(void);
static void *smbd_localtime_monitor(void *arg);

static void smbd_dyndns_init(void);
static void smbd_load_shares(void);
static void *smbd_share_loader(void *);

static void smbd_refresh_handler(void);

static int smbd_kernel_start(void);

smbd_t smbd;

/*
 * Use SMF error codes only on return or exit.
 */
int
main(int argc, char *argv[])
{
        sigset_t                set;
        uid_t                   uid;
        int                     pfd = -1;
        int                     sigval;
        struct rlimit           rl;
        int                     orig_limit;

#ifdef  FKSMBD
        fksmbd_init();
#endif
        smbd.s_pname = basename(argv[0]);
        openlog(smbd.s_pname, LOG_PID | LOG_NOWAIT, LOG_DAEMON);

        if (smbd_setup_options(argc, argv) != 0)
                return (SMF_EXIT_ERR_FATAL);

        if ((uid = getuid()) != smbd.s_uid) {
#ifdef  FKSMBD
                /* Can't manipulate privileges in daemonize. */
                if (smbd.s_fg == 0) {
                        smbd.s_fg = 1;
                        smbd_report("user %d (forced -f)", uid);
                }
#else   /* FKSMBD */
                smbd_report("user %d: %s", uid, strerror(EPERM));
                return (SMF_EXIT_ERR_FATAL);
#endif  /* FKSMBD */
        }

        if (is_system_labeled()) {
                smbd_report("Trusted Extensions not supported");
                return (SMF_EXIT_ERR_FATAL);
        }

        if (smbd_already_running())
                return (SMF_EXIT_OK);

        /*
         * Raise the file descriptor limit to accommodate simultaneous user
         * authentications/file access.
         */
        if ((getrlimit(RLIMIT_NOFILE, &rl) == 0) &&
            (rl.rlim_cur < rl.rlim_max)) {
                orig_limit = rl.rlim_cur;
                rl.rlim_cur = rl.rlim_max;
                if (setrlimit(RLIMIT_NOFILE, &rl) != 0)
                        smbd_report("Failed to raise file descriptor limit"
                            " from %d to %d", orig_limit, rl.rlim_cur);
        }

        /*
         * Block async signals in all threads.
         */
        (void) sigemptyset(&set);

        (void) sigaddset(&set, SIGHUP);
        (void) sigaddset(&set, SIGINT);
        (void) sigaddset(&set, SIGQUIT);
        (void) sigaddset(&set, SIGPIPE);
        (void) sigaddset(&set, SIGTERM);
        (void) sigaddset(&set, SIGUSR1);
        (void) sigaddset(&set, SIGUSR2);

        (void) sigprocmask(SIG_SETMASK, &set, NULL);

        if (smbd.s_fg) {
                if (smbd_service_init() != 0) {
                        smbd_report("service initialization failed");
                        exit(SMF_EXIT_ERR_FATAL);
                }
        } else {
                /*
                 * "pfd" is a pipe descriptor -- any fatal errors
                 * during subsequent initialization of the child
                 * process should be written to this pipe and the
                 * parent will report this error as the exit status.
                 */
                pfd = smbd_daemonize_init();

                if (smbd_service_init() != 0) {
                        smbd_report("daemon initialization failed");
                        exit(SMF_EXIT_ERR_FATAL);
                }

                smbd_daemonize_fini(pfd, SMF_EXIT_OK);
        }

        while (!smbd.s_shutting_down) {
                sigval = sigwait(&set);

                switch (sigval) {
                case -1:
                        syslog(LOG_DEBUG, "sigwait failed: %s",
                            strerror(errno));
                        break;
                case SIGPIPE:
                        break;

                case SIGHUP:
                        syslog(LOG_DEBUG, "refresh requested");
                        smbd_refresh_handler();
                        break;

                case SIGUSR1:
                        syslog(LOG_DEBUG, "SIGUSR1 ignored");
                        break;

                default:
                        /*
                         * Typically SIGINT or SIGTERM.
                         */
                        smbd.s_shutting_down = B_TRUE;
                        break;
                }
        }

        /*
         * Allow termination signals while shutting down.
         */
        (void) sigemptyset(&set);

        if (smbd.s_fg) {
                (void) sigaddset(&set, SIGHUP);
                (void) sigaddset(&set, SIGINT);
        }
        (void) sigaddset(&set, SIGTERM);

        (void) sigprocmask(SIG_UNBLOCK, &set, NULL);

        smbd_service_fini();
        return ((smbd.s_fatal_error) ? SMF_EXIT_ERR_FATAL : SMF_EXIT_OK);
}

/*
 * This function will fork off a child process,
 * from which only the child will return.
 *
 * Use SMF error codes only on exit.
 */
static int
smbd_daemonize_init(void)
{
        int status, pfds[2];
        sigset_t set, oset;
        pid_t pid;
        int rc;

        /*
         * Reset privileges to the minimum set required. We continue
         * to run as root to create and access files in /var.
         */
        rc = smb_init_daemon_priv(PU_RESETGROUPS, smbd.s_uid, smbd.s_gid);

        if (rc != 0) {
                smbd_report("insufficient privileges");
                exit(SMF_EXIT_ERR_FATAL);
        }

        /*
         * Block all signals prior to the fork and leave them blocked in the
         * parent so we don't get in a situation where the parent gets SIGINT
         * and returns non-zero exit status and the child is actually running.
         * In the child, restore the signal mask once we've done our setsid().
         */
        (void) sigfillset(&set);
        (void) sigdelset(&set, SIGABRT);
        (void) sigprocmask(SIG_BLOCK, &set, &oset);

        if (pipe(pfds) == -1) {
                smbd_report("unable to create pipe");
                exit(SMF_EXIT_ERR_FATAL);
        }

        closelog();

        if ((pid = fork()) == -1) {
                openlog(smbd.s_pname, LOG_PID | LOG_NOWAIT, LOG_DAEMON);
                smbd_report("unable to fork");
                closelog();
                exit(SMF_EXIT_ERR_FATAL);
        }

        /*
         * If we're the parent process, wait for either the child to send us
         * the appropriate exit status over the pipe or for the read to fail
         * (presumably with 0 for EOF if our child terminated abnormally).
         * If the read fails, exit with either the child's exit status if it
         * exited or with SMF_EXIT_ERR_FATAL if it died from a fatal signal.
         */
        if (pid != 0) {
                (void) close(pfds[1]);

                if (read(pfds[0], &status, sizeof (status)) == sizeof (status))
                        _exit(status);

                if (waitpid(pid, &status, 0) == pid && WIFEXITED(status))
                        _exit(WEXITSTATUS(status));

                _exit(SMF_EXIT_ERR_FATAL);
        }

        openlog(smbd.s_pname, LOG_PID | LOG_NOWAIT, LOG_DAEMON);
        (void) setsid();
        (void) sigprocmask(SIG_SETMASK, &oset, NULL);
        (void) chdir("/");
        (void) umask(022);
        (void) close(pfds[0]);

        return (pfds[1]);
}

/*
 * This function is based on __init_daemon_priv() and replaces
 * __init_daemon_priv() since we want smbd to have all privileges so that it
 * can execute map/unmap commands with all privileges during share
 * connection/disconnection.  Unused privileges are disabled until command
 * execution.  The permitted and the limit set contains all privileges.  The
 * inheritable set contains no privileges.
 */

static const char root_cp[] = "/core.%f.%t";
static const char daemon_cp[] = "/var/tmp/core.%f.%t";

static int
smb_init_daemon_priv(int flags, uid_t uid, gid_t gid)
{
        priv_set_t *perm = NULL;
        int ret = -1;
        char buf[1024];

        /*
         * This is not a significant failure: it allows us to start programs
         * with sufficient privileges and with the proper uid.   We don't
         * care enough about the extra groups in that case.
         */
        if (flags & PU_RESETGROUPS)
                (void) setgroups(0, NULL);

        if (gid != (gid_t)-1 && setgid(gid) != 0)
                goto end;

        perm = priv_allocset();
        if (perm == NULL)
                goto end;

        /* E = P */
        (void) getppriv(PRIV_PERMITTED, perm);
        (void) setppriv(PRIV_SET, PRIV_EFFECTIVE, perm);

        /* Now reset suid and euid */
        if (uid != (uid_t)-1 && setreuid(uid, uid) != 0)
                goto end;

        /* I = 0 */
        priv_emptyset(perm);
        ret = setppriv(PRIV_SET, PRIV_INHERITABLE, perm);
end:
        priv_freeset(perm);

        if (core_get_process_path(buf, sizeof (buf), getpid()) == 0 &&
            strcmp(buf, "core") == 0) {

                if ((uid == (uid_t)-1 ? geteuid() : uid) == 0) {
                        (void) core_set_process_path(root_cp, sizeof (root_cp),
                            getpid());
                } else {
                        (void) core_set_process_path(daemon_cp,
                            sizeof (daemon_cp), getpid());
                }
        }
        (void) setpflags(__PROC_PROTECT, 0);

        return (ret);
}

/*
 * Most privileges, except the ones that are required for smbd, are turn off
 * in the effective set.  They will be turn on when needed for command
 * execution during share connection/disconnection.
 */
static void
smbd_daemonize_fini(int fd, int exit_status)
{
        priv_set_t *pset;

        /*
         * Now that we're running, if a pipe fd was specified, write an exit
         * status to it to indicate that our parent process can safely detach.
         * Then proceed to loading the remaining non-built-in modules.
         */
        if (fd >= 0)
                (void) write(fd, &exit_status, sizeof (exit_status));

        (void) close(fd);

        pset = priv_allocset();
        if (pset == NULL)
                return;

        priv_basicset(pset);

        /* list of privileges for smbd */
        (void) priv_addset(pset, PRIV_NET_MAC_AWARE);
        (void) priv_addset(pset, PRIV_NET_PRIVADDR);
        (void) priv_addset(pset, PRIV_PROC_AUDIT);
        (void) priv_addset(pset, PRIV_SYS_CONFIG);
        (void) priv_addset(pset, PRIV_SYS_DEVICES);
        (void) priv_addset(pset, PRIV_SYS_SMB);
        (void) priv_addset(pset, PRIV_SYS_MOUNT);

        priv_inverse(pset);

        /* turn off unneeded privileges */
        (void) setppriv(PRIV_OFF, PRIV_EFFECTIVE, pset);

        priv_freeset(pset);

        /* reenable core dumps */
        __fini_daemon_priv(NULL);
}

/*
 * smbd_service_init
 */
static int
smbd_service_init(void)
{
        static struct dir {
                char    *name;
                int     perm;
        } dir[] = {
                { SMB_DBDIR,    0700 },
                { SMB_CVOL,     0755 },
                { SMB_SYSROOT,  0755 },
                { SMB_SYSTEM32, 0755 },
                { SMB_VSS,      0755 },
                { SMB_PIPE_DIR, 0755 },
                { "/var/smb/lipc", 0755 },
        };
        int     rc, i;

        smbd.s_pid = getpid();

        /*
         * Stop for a debugger attach here, which is after the
         * fork() etc. in smb_daemonize_init()
         */
        if (smbd.s_dbg_stop) {
                smbd_report("pid %d stop for debugger attach", smbd.s_pid);
                (void) kill(smbd.s_pid, SIGSTOP);
        }
        smbd_report("smbd starting, pid %d", smbd.s_pid);

        for (i = 0; i < sizeof (dir)/sizeof (dir[0]); ++i) {
                if ((mkdir(dir[i].name, dir[i].perm) < 0) &&
                    (errno != EEXIST)) {
                        smbd_report("mkdir %s: %s", dir[i].name,
                            strerror(errno));
                        return (-1);
                }
        }

        /*
         * This environment variable tells mech_krb5 to give us
         * MS-compatible behavior.
         */
        (void) putenv("MS_INTEROP=1");

        if ((rc = smb_ccache_init(SMB_VARRUN_DIR, SMB_CCACHE_FILE)) != 0) {
                if (rc == -1)
                        smbd_report("mkdir %s: %s", SMB_VARRUN_DIR,
                            strerror(errno));
                else
                        smbd_report("unable to set KRB5CCNAME");
                return (-1);
        }

#ifndef FKSMBD
        /* Upgrade SMF settings, if necessary. */
        smb_config_upgrade();
#endif

        smb_codepage_init();

        rc = smbd_cups_init();
        if (smb_config_getbool(SMB_CI_PRINT_ENABLE))
                smbd_report("print service %savailable", (rc == 0) ? "" : "un");

        if (smbd_nicmon_start(SMBD_DEFAULT_INSTANCE_FMRI) != 0)
                smbd_report("NIC monitor failed to start");

        smbd_dyndns_init();
        smb_ipc_init();

        if (smb_config_getbool(SMB_CI_NETBIOS_ENABLE) == 0)
                smbd_report("NetBIOS services disabled");
        else if (smb_netbios_start() != 0)
                smbd_report("NetBIOS services failed to start");
        else
                smbd_report("NetBIOS services started");

        smbd.s_secmode = smb_config_get_secmode();
        if ((rc = smb_domain_init(smbd.s_secmode)) != 0) {
                if (rc == SMB_DOMAIN_NOMACHINE_SID) {
                        smbd_report(
                            "no machine SID: check idmap configuration");
                        return (-1);
                }
        }

        if (smbd_dc_monitor_init() != 0)
                smbd_report("DC monitor initialization failed %s",
                    strerror(errno));

        if (smbd_pipesvc_start() != 0) {
                smbd_report("pipesvc initialization failed");
                return (-1);
        }

        if (smbd_authsvc_start() != 0) {
                smbd_report("authsvc initialization failed");
                return (-1);
        }

        smbd.s_door_srv = smbd_door_start();
        if (smbd.s_door_srv < 0) {
                smbd_report("door initialization failed %s", strerror(errno));
                return (-1);
        }

        dyndns_update_zones();
        smbd_localtime_init();
        (void) smb_lgrp_start();
        smb_pwd_init(B_TRUE);

        if (smb_shr_start() != 0) {
                smbd_report("share initialization failed: %s", strerror(errno));
                return (-1);
        }

        smbd.s_door_lmshr = smbd_share_start();
        if (smbd.s_door_lmshr < 0)
                smbd_report("share initialization failed");

        /* Open the driver, load the kernel config. */
        if (smbd_kernel_bind() != 0) {
                return (-1);
        }

        smbd_load_shares();
        smbd_load_printers();
        smbd_spool_start();

        smbd.s_initialized = B_TRUE;
        smbd_report("service initialized");

        return (0);
}

/*
 * Shutdown smbd and smbsrv kernel services.
 *
 * Called only by the main thread.
 */
static void
smbd_service_fini(void)
{

        smbd.s_shutting_down = B_TRUE;
        smbd_report("service shutting down");

        smb_kmod_stop();
        smb_logon_abort();
        smb_lgrp_stop();
        smbd_pipesvc_stop();
        smbd_door_stop();
        smbd_authsvc_stop();
        smbd_spool_stop();
        smbd_kernel_unbind();
        smbd_share_stop();
        smb_shr_unload();
        smb_shr_stop();
        dyndns_stop();
        smbd_nicmon_stop();
        smb_ccache_remove(SMB_CCACHE_PATH);
        smb_pwd_fini();
        smb_domain_fini();
        mlsvc_fini();
        smb_netbios_stop();
        smbd_cups_fini();

        smbd.s_initialized = B_FALSE;
        smbd_report("service terminated");
        closelog();
}

/*
 * Called when SMF sends us a SIGHUP.  Update the smbd configuration
 * from SMF and check for changes that require service reconfiguration.
 */
static void
smbd_refresh_handler()
{
        int new_debug;

        if (smbd.s_shutting_down)
                return;

        smbd.s_refreshes++;

        new_debug = smb_config_get_debug();
        if (smbd.s_debug || new_debug)
                smbd_report("debug=%d", new_debug);
        smbd.s_debug = new_debug;

        smbd_spool_stop();
        smbd_dc_monitor_refresh();
        smb_ccache_remove(SMB_CCACHE_PATH);

        /*
         * Clear the DNS zones for the existing interfaces
         * before updating the NIC interface list.
         */
        dyndns_clear_zones();

        if (smbd_nicmon_refresh() != 0)
                smbd_report("NIC monitor refresh failed");

        smb_netbios_name_reconfig();
        smb_browser_reconfig();
        dyndns_update_zones();

        /* This reloads the in-kernel config. */
        (void) smbd_kernel_bind();

        /* On refresh load share properties only, not the shares themselves */
        smb_shr_load_execinfo();

        smbd_load_printers();
        smbd_spool_start();
}

void
smbd_set_secmode(int secmode)
{
        switch (secmode) {
        case SMB_SECMODE_WORKGRP:
        case SMB_SECMODE_DOMAIN:
                (void) smb_config_set_secmode(secmode);
                smbd.s_secmode = secmode;
                break;

        default:
                syslog(LOG_ERR, "invalid security mode: %d", secmode);
                syslog(LOG_ERR, "entering maintenance mode");
                (void) smb_smf_maintenance_mode();
        }
}

/*
 * The service is online if initialization is complete and shutdown
 * has not begun.
 */
boolean_t
smbd_online(void)
{
        return (smbd.s_initialized && !smbd.s_shutting_down);
}

/*
 * Wait until the service is online.  Provided for threads that
 * should wait until the service has been fully initialized before
 * they start performing operations.
 */
void
smbd_online_wait(const char *text)
{
        while (!smbd_online())
                (void) sleep(SMBD_ONLINE_WAIT_INTERVAL);

        if (text != NULL) {
                syslog(LOG_DEBUG, "%s: online", text);
                (void) fprintf(stderr, "%s: online\n", text);
        }
}

/*
 * If the door has already been opened by another process (non-zero pid
 * in target), we assume that another smbd is already running.  If there
 * is a race here, it will be caught later when smbsrv is opened because
 * only one process is allowed to open the device at a time.
 */
static int
smbd_already_running(void)
{
        door_info_t     info;
        char            *door_name;
        int             door;

        door_name = getenv("SMBD_DOOR_NAME");
        if (door_name == NULL)
                door_name = SMBD_DOOR_NAME;

        if ((door = open(door_name, O_RDONLY)) < 0)
                return (0);

        if (door_info(door, &info) < 0)
                return (0);

        if (info.di_target > 0) {
                smbd_report("already running: pid %ld\n", info.di_target);
                (void) close(door);
                return (1);
        }

        (void) close(door);
        return (0);
}

/*
 * smbd_kernel_bind
 *
 * If smbsrv is already bound, reload the configuration and update smbsrv.
 * Otherwise, open the smbsrv device and start the kernel service.
 */
static int
smbd_kernel_bind(void)
{
        smb_kmod_cfg_t  cfg;
        int             rc;

        if (smbd.s_kbound) {
                smb_load_kconfig(&cfg);
                smbd_get_authconf(&cfg);
                rc = smb_kmod_setcfg(&cfg);
                if (rc < 0)
                        smbd_report("kernel configuration update failed: %s",
                            strerror(rc));
                return (rc);
        }

        if (smb_kmod_isbound())
                smbd_kernel_unbind();

        if ((rc = smb_kmod_bind(B_TRUE)) == 0) {
                rc = smbd_kernel_start();
                if (rc != 0)
                        smb_kmod_unbind();
                else
                        smbd.s_kbound = B_TRUE;
        } else {
                smbd_report("kernel bind error: %s", strerror(rc));
        }

        return (rc);
}

static int
smbd_kernel_start(void)
{
        smb_kmod_cfg_t  cfg;
        int             rc;

        smb_load_kconfig(&cfg);
        smbd_get_authconf(&cfg);
        rc = smb_kmod_setcfg(&cfg);
        if (rc != 0) {
                smbd_report("kernel config ioctl error: %s", strerror(rc));
                return (rc);
        }

        rc = smb_kmod_setgmtoff(smbd_gmtoff());
        if (rc != 0) {
                smbd_report("kernel gmtoff ioctl error: %s", strerror(rc));
                return (rc);
        }

        rc = smb_kmod_start(smbd.s_door_opipe, smbd.s_door_lmshr,
            smbd.s_door_srv);

        if (rc != 0) {
                smbd_report("kernel start ioctl error: %s", strerror(rc));
                return (rc);
        }

        return (0);
}

/*
 * smbd_kernel_unbind
 */
static void
smbd_kernel_unbind(void)
{
        smb_kmod_unbind();
        smbd.s_kbound = B_FALSE;
}

/*
 * Create the Dynamic DNS publisher thread.
 */
static void
smbd_dyndns_init(void)
{
        pthread_t       tid;
        pthread_attr_t  attr;
        int             rc;

        dyndns_start();

        (void) pthread_attr_init(&attr);
        (void) pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
        rc = pthread_create(&tid, &attr, dyndns_publisher, NULL);
        (void) pthread_attr_destroy(&attr);

        if (rc != 0)
                smbd_report("unable to start dyndns publisher: %s",
                    strerror(errno));
}

/*
 * Launches a thread to populate the share cache by share information
 * stored in sharemgr
 */
static void
smbd_load_shares(void)
{
        pthread_t       tid;
        pthread_attr_t  attr;
        int             rc;

        (void) pthread_attr_init(&attr);
        (void) pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
        rc = pthread_create(&tid, &attr, smbd_share_loader, NULL);
        (void) pthread_attr_destroy(&attr);

        if (rc != 0)
                smbd_report("unable to load disk shares: %s", strerror(errno));
}

/*
 * This wrapper function is used to avoid casting smb_shr_load() in
 * pthread_create() above. It is called very infrequently.
 */
static void *
smbd_share_loader(void *args)
{
        (void) smb_shr_load(args);
        return (NULL);
}

/*
 * Initialization of the localtime thread.
 * Returns 0 on success, an error number if thread creation fails.
 */

static void
smbd_localtime_init(void)
{
        pthread_attr_t  attr;
        int             rc;

        (void) pthread_attr_init(&attr);
        (void) pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
        rc = pthread_create(&smbd.s_localtime_tid, &attr,
            smbd_localtime_monitor, NULL);
        (void) pthread_attr_destroy(&attr);

        if (rc != 0)
                smbd_report("unable to monitor localtime: %s", strerror(errno));
}

/*
 * Send local gmtoff to the kernel module one time at startup and each
 * time it changes (up to twice a year).
 * Local gmtoff is checked once every 15 minutes since some timezones
 * are aligned on half and quarter hour boundaries.
 */
/*ARGSUSED*/
static void *
smbd_localtime_monitor(void *arg)
{
        struct tm local_tm;
        time_t secs;
        int32_t gmtoff, last_gmtoff = -1;
        int timeout;
        int error;

        smbd_online_wait("smbd_localtime_monitor");

        for (;;) {
                gmtoff = smbd_gmtoff();

                if ((last_gmtoff != gmtoff) && smbd.s_kbound) {
                        error = smb_kmod_setgmtoff(gmtoff);
                        if (error != 0)
                                smbd_report("localtime set failed: %s",
                                    strerror(error));
                }

                /*
                 * Align the next iteration on a fifteen minute boundary.
                 */
                secs = time(0);
                (void) localtime_r(&secs, &local_tm);
                timeout = ((15 - (local_tm.tm_min % 15)) * SECSPERMIN);
                (void) sleep(timeout);

                last_gmtoff = gmtoff;
        }

        /*NOTREACHED*/
        return (NULL);
}

/*
 * smbd_gmtoff
 *
 * Determine offset from GMT. If daylight saving time use altzone,
 * otherwise use timezone.
 */
static int32_t
smbd_gmtoff(void)
{
        time_t clock_val;
        struct tm *atm;
        int32_t gmtoff;

        (void) time(&clock_val);
        atm = localtime(&clock_val);

        gmtoff = (atm->tm_isdst) ? altzone : timezone;

        return (gmtoff);
}

/*
 * Set up configuration options and parse the command line.
 * This function will determine if we will run as a daemon
 * or in the foreground.
 *
 * Failure to find a uid or gid results in using the default (0).
 */
static int
smbd_setup_options(int argc, char *argv[])
{
        struct passwd *pwd;
        struct group *grp;
        int c;

        if ((pwd = getpwnam("root")) != NULL)
                smbd.s_uid = pwd->pw_uid;

        if ((grp = getgrnam("sys")) != NULL)
                smbd.s_gid = grp->gr_gid;

        smbd.s_debug = smb_config_get_debug();
        smbd.s_fg = smb_config_get_fg_flag();

        while ((c = getopt(argc, argv, ":dfs")) != -1) {
                switch (c) {
                case 'd':
                        smbd.s_debug++;
                        break;
                case 'f':
                        smbd.s_fg = 1;
                        break;
                case 's':
                        smbd.s_dbg_stop = 1;
                        break;
                case ':':
                case '?':
                default:
                        smbd_usage(stderr);
                        return (-1);
                }
        }

        return (0);
}

static void
smbd_usage(FILE *fp)
{
        static char *help[] = {
                "-d  enable debug messages"
                "-f  run program in foreground"
        };

        int i;

        (void) fprintf(fp, "Usage: %s [-f]\n", smbd.s_pname);

        for (i = 0; i < sizeof (help)/sizeof (help[0]); ++i)
                (void) fprintf(fp, "    %s\n", help[i]);
}

void
smbd_report(const char *fmt, ...)
{
        char buf[128];
        va_list ap;

        if (fmt == NULL)
                return;

        va_start(ap, fmt);
        (void) vsnprintf(buf, 128, fmt, ap);
        va_end(ap);

        (void) fprintf(stderr, "smbd: %s\n", buf);
}

/*
 * Once we're out of memory, we're not likely to recover
 * without a restart. Let SMF restart this service.
 */
void
smbd_nomem(void)
{
        smbd_report(strerror(ENOMEM));
        if (smbd.s_debug)
                abort();
        exit(1);
}

/*
 * Enable libumem debugging by default on DEBUG builds.
 */
#ifdef DEBUG
const char *
_umem_debug_init(void)
{
        return ("default,verbose"); /* $UMEM_DEBUG setting */
}

const char *
_umem_logging_init(void)
{
        return ("fail,contents"); /* $UMEM_LOGGING setting */
}
#endif