smbsrv/smbd/smbd_main.c

	smbd_main.c revision da6c28aaf62fa55f0fdb8004aa40f88f23bf53f0
/*
 * 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 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioccom.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 <libscf.h>
#include <limits.h>
#include <priv_utils.h>
#include <door.h>
#include <errno.h>
#include <syslog.h>
#include <pthread.h>
#include <time.h>
#include <libscf.h>
#include <zone.h>
#include <tzfile.h>
#include <libgen.h>
#include <pwd.h>
#include <grp.h>

#include <smbsrv/smb_door_svc.h>
#include <smbsrv/smb_ioctl.h>
#include <smbsrv/libsmb.h>
#include <smbsrv/libsmbns.h>
#include <smbsrv/libsmbrdr.h>
#include <smbsrv/libmlsvc.h>

#include "smbd.h"

#define DRV_DEVICE_PATH "/devices/pseudo/smbsrv@0:smbsrv"
#define SMB_CACHEDIR "/var/run/smb"
#define SMB_DBDIR "/var/smb"

extern void smb_netbios_name_reconfig();
extern void smb_browser_config();

static int smbd_daemonize_init(void);
static void smbd_daemonize_fini(int, int);

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 void smbd_report(const char *fmt, ...);

static void smbd_sig_handler(int sig);

static int smbd_localtime_init(void);
static void *smbd_localtime_monitor(void *arg);

extern time_t altzone;

static pthread_t localtime_thr;

static int smbd_refresh_init(void);
static void smbd_refresh_fini(void);
static void *smbd_refresh_monitor(void *);
static pthread_t refresh_thr;
static pthread_cond_t refresh_cond;
static pthread_mutex_t refresh_mutex;

static smbd_t smbd;

/*
 * smbd user land daemon
 *
 * Use SMF error codes only on return or exit.
 */
int
main(int argc, char *argv[])
{
    struct sigaction act;
    sigset_t set;
    uid_t uid;
    int pfd = -1;

    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) {
        smbd_report("user %d: %s", uid, strerror(EPERM));
        return (SMF_EXIT_ERR_FATAL);
    }

    if (getzoneid() != GLOBAL_ZONEID) {
        smbd_report("non-global zones are not supported");
        return (SMF_EXIT_ERR_FATAL);
    }

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

    if (smbd_already_running())
        return (SMF_EXIT_OK);

    (void) sigfillset(&set);
    (void) sigdelset(&set, SIGABRT);

    (void) sigfillset(&act.sa_mask);
    act.sa_handler = smbd_sig_handler;
    act.sa_flags = 0;

    (void) sigaction(SIGTERM, &act, NULL);
    (void) sigaction(SIGHUP, &act, NULL);
    (void) sigaction(SIGINT, &act, NULL);
    (void) sigaction(SIGPIPE, &act, NULL);

    (void) sigdelset(&set, SIGTERM);
    (void) sigdelset(&set, SIGHUP);
    (void) sigdelset(&set, SIGINT);
    (void) sigdelset(&set, SIGPIPE);

    if (smbd.s_fg) {
        (void) sigdelset(&set, SIGTSTP);
        (void) sigdelset(&set, SIGTTIN);
        (void) sigdelset(&set, SIGTTOU);

        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);
    }

    (void) atexit(smbd_service_fini);

    while (!smbd.s_shutdown_flag) {
        (void) sigsuspend(&set);

        switch (smbd.s_sigval) {
        case 0:
            break;

        case SIGPIPE:
            break;

        case SIGHUP:
            /* Refresh config was triggered */
            if (smbd.s_fg)
                smbd_report("reconfiguration requested");
            (void) pthread_cond_signal(&refresh_cond);
            break;

        default:
            /*
             * Typically SIGINT or SIGTERM.
             */
            smbd.s_shutdown_flag = 1;
            break;
        }

        smbd.s_sigval = 0;
    }

    smbd_service_fini();
    closelog();
    return (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 = __init_daemon_priv(PU_RESETGROUPS | PU_LIMITPRIVS,
        smbd.s_uid, smbd.s_gid,
        PRIV_NET_MAC_AWARE, PRIV_NET_PRIVADDR, PRIV_PROC_AUDIT,
        PRIV_SYS_DEVICES, PRIV_SYS_SMB, NULL);

    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);
    smbd.s_pid = getpid();
    (void) setsid();
    (void) sigprocmask(SIG_SETMASK, &oset, NULL);
    (void) chdir("/");
    (void) umask(022);
    (void) close(pfds[0]);

    return (pfds[1]);
}

static void
smbd_daemonize_fini(int fd, int exit_status)
{
    /*
     * 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);

    if ((fd = open("/dev/null", O_RDWR)) >= 0) {
        (void) fcntl(fd, F_DUP2FD, STDIN_FILENO);
        (void) fcntl(fd, F_DUP2FD, STDOUT_FILENO);
        (void) fcntl(fd, F_DUP2FD, STDERR_FILENO);
        (void) close(fd);
    }

    __fini_daemon_priv(PRIV_PROC_FORK, PRIV_PROC_EXEC, PRIV_PROC_SESSION,
        PRIV_FILE_LINK_ANY, PRIV_PROC_INFO, NULL);
}

static int
smbd_service_init(void)
{
    static char *dir[] = {
        SMB_DBDIR,      /* smbpasswd */
        SMB_CACHEDIR        /* KRB credential cache */
    };

    int rc;
    int ddns_enabled;
    uint32_t mode;
    char resource_domain[SMB_PI_MAX_DOMAIN];
    int i;

    smbd.s_drv_fd = -1;

    for (i = 0; i < (sizeof (dir)/sizeof (dir[0])); ++i) {
        errno = 0;

        if ((mkdir(dir[i], 0700) < 0) && (errno != EEXIST)) {
            smbd_report("mkdir %s: %s", dir[i], strerror(errno));
            return (1);
        }
    }

    /*
     * Set KRB5CCNAME (for the SMB credential cache) in the environment.
     */
    if (putenv("KRB5CCNAME=" SMB_CACHEDIR "/ccache") != 0) {
        smbd_report("unable to set KRB5CCNAME");
        return (1);
    }

    (void) oem_language_set("english");

    if (!nt_builtin_init()) {
        smbd_report("out of memory");
        return (1);
    }

    /*
     * Need to load the configuration data prior to getting the
     * interface information.
     */
    if (smb_config_load() != 0) {
        smbd_report("failed to load configuration data");
        return (1);
    }

    smb_resolver_init();
    (void) smb_nicmon_start();

    smbrdr_init();

    smb_netbios_start();
    if (smb_netlogon_init() != 0) {
        smbd_report("netlogon initialization failed");
        return (1);
    }

    smb_config_rdlock();
    resource_domain[0] = '\0';
    (void) strlcpy(resource_domain,
        smb_config_getstr(SMB_CI_DOMAIN_NAME), SMB_PI_MAX_DOMAIN);
    (void) utf8_strupr(resource_domain);
    smb_config_unlock();

    mode = smb_get_security_mode();

    if (mode == SMB_SECMODE_DOMAIN)
        (void) locate_resource_pdc(resource_domain);

    /* Get the ID map client handle */
    if ((rc = smb_idmap_start()) != 0) {
        smbd_report("no idmap handle");
        return (rc);
    }

    if ((rc = nt_domain_init(resource_domain, mode)) != 0) {
        if (rc == SMB_DOMAIN_NOMACHINE_SID)
            smbd_report("No Security Identifier (SID) has been "
                "generated for this system.\n"
                "Check idmap service configuration.");

        if (rc == SMB_DOMAIN_NODOMAIN_SID) {
            /* Get the domain sid from domain controller */
            if ((rc = lsa_query_primary_domain_info()) != 0)
                smbd_report("Failed to get the Security "
                    "Identifier (SID) of domain %s",
                    resource_domain);
            }
        return (rc);
    }

    if ((rc = mlsvc_init()) != 0) {
        smbd_report("msrpc initialization failed");
        return (rc);
    }

    if (rc = smb_mlsvc_srv_start()) {
        smbd_report("msrpc door initialization failed: %d", rc);
        return (rc);
    }

    if (smb_lmshrd_srv_start() != 0) {
        smbd_report("share initialization failed");
    }

    /* XXX following will get removed */
    (void) smb_doorsrv_start();
    if ((rc = smb_door_srv_start()) != 0)
        return (rc);

    if ((rc = smbd_refresh_init()) != 0)
        return (rc);

    /* Call dyndns update - Just in case its configured to refresh DNS */
    smb_config_rdlock();
    ddns_enabled = smb_config_getyorn(SMB_CI_DYNDNS_ENABLE);
    smb_config_unlock();
    if (ddns_enabled) {
        (void) dyndns_update();
    }

    if ((rc = smbd_kernel_bind()) != 0)
        smbd_report("kernel bind error: %s", strerror(errno));

    (void) smbd_localtime_init();

    return (lmshare_start());
}

/*
 * Close the kernel service and shutdown smbd services.
 * This function is registered with atexit(): ensure that anything
 * called from here is safe to be called multiple times.
 */
static void
smbd_service_fini(void)
{
    nt_builtin_fini();
    smbd_refresh_fini();
    smbd_kernel_unbind();
    smb_door_srv_stop();
    smb_doorsrv_stop();
    smb_lmshrd_srv_stop();
    lmshare_stop();
    smb_mlsvc_srv_stop();
    smb_nicmon_stop();
    smb_resolver_close();
    smb_idmap_stop();
}

/*
 * smbd_refresh_init()
 *
 * SMB service refresh thread initialization.  This thread waits for a
 * refresh event and updates the daemon's view of the configuration
 * before going back to sleep.
 */
static int
smbd_refresh_init()
{
    pthread_attr_t tattr;
    pthread_condattr_t cattr;
    int rc;

    (void) pthread_condattr_init(&cattr);
    (void) pthread_cond_init(&refresh_cond, &cattr);
    (void) pthread_condattr_destroy(&cattr);

    (void) pthread_mutex_init(&refresh_mutex, NULL);

    (void) pthread_attr_init(&tattr);
    (void) pthread_attr_setdetachstate(&tattr, PTHREAD_CREATE_DETACHED);
    rc = pthread_create(&refresh_thr, &tattr, smbd_refresh_monitor, 0);
    (void) pthread_attr_destroy(&tattr);
    return (rc);

}

/*
 * smbd_refresh_fini()
 *
 * Stop the refresh thread.
 */
static void
smbd_refresh_fini()
{
    (void) pthread_cancel(refresh_thr);

    (void) pthread_cond_destroy(&refresh_cond);
    (void) pthread_mutex_destroy(&refresh_mutex);
}

/*
 * smbd_refresh_monitor()
 *
 * Wait for a refresh event. When this thread wakes up, update the
 * smbd configuration from the SMF config information then go back to
 * wait for the next refresh.
 */
/*ARGSUSED*/
static void *
smbd_refresh_monitor(void *arg)
{
    int dummy = 0;

    (void) pthread_mutex_lock(&refresh_mutex);
    while (pthread_cond_wait(&refresh_cond, &refresh_mutex) == 0) {
        /*
         * We've been woken up by a refresh event so go do
         * what is necessary.
         */
        (void) smb_config_load();
        smb_nic_build_info();
        (void) smb_netbios_name_reconfig();
        (void) smb_browser_config();
        if (ioctl(smbd.s_drv_fd, SMB_IOC_CONFIG_REFRESH, &dummy) < 0) {
            smbd_report("configuration update ioctl: %s",
                strerror(errno));
        }
    }
    return (NULL);
}


/*
 * 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;
    int door;

    if ((door = open(SMBD_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);
}

static int
smbd_kernel_bind(void)
{
    if (smbd.s_drv_fd != -1)
        (void) close(smbd.s_drv_fd);

    if ((smbd.s_drv_fd = open(DRV_DEVICE_PATH, 0)) < 0) {
        smbd.s_drv_fd = -1;
        return (1);
    }
    return (0);
}


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

int
smbd_localtime_init(void)
{
    pthread_attr_t tattr;
    int rc;

    (void) pthread_attr_init(&tattr);
    (void) pthread_attr_setdetachstate(&tattr, PTHREAD_CREATE_DETACHED);
    rc = pthread_create(&localtime_thr, &tattr, smbd_localtime_monitor, 0);
    (void) pthread_attr_destroy(&tattr);
    return (rc);
}

/*
 * Local time thread to kernel land.
 * Send local gmtoff to kernel module one time at startup
 * and each time it changes (up to twice a year).
 * Local gmtoff is checked once every 15 minutes and
 * since some timezones are aligned on half and qtr hour boundaries,
 * once an hour would likely suffice.
 */

/*ARGSUSED*/
static void *
smbd_localtime_monitor(void *arg)
{
    struct tm local_tm;
    time_t secs, gmtoff;
    time_t last_gmtoff = -1;
    int timeout;

    for (;;) {
        gmtoff = -altzone;

        if ((last_gmtoff != gmtoff) && (smbd.s_drv_fd != -1)) {
            if (ioctl(smbd.s_drv_fd, SMB_IOC_GMTOFF, &gmtoff) < 0) {
                smbd_report("localtime ioctl: %s",
                    strerror(errno));
            }
        }

        /*
         * 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);
}


static void
smbd_kernel_unbind(void)
{
    if (smbd.s_drv_fd != -1) {
        (void) close(smbd.s_drv_fd);
        smbd.s_drv_fd = -1;
    }
}

static void
smbd_sig_handler(int sigval)
{
    if (smbd.s_sigval == 0)
        smbd.s_sigval = sigval;
}

/*
 * 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_fg = smb_get_fg_flag();

    while ((c = getopt(argc, argv, ":f")) != -1) {
        switch (c) {
        case 'f':
            smbd.s_fg = 1;
            break;

        case ':':
        case '?':
        default:
            smbd_usage(stderr);
            return (-1);
        }
    }

    return (0);
}

static void
smbd_usage(FILE *fp)
{
    static char *help[] = {
        "-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]);
}

static 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);
}

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

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