libsmb/common/smb_domain.c

	smb_domain.c revision bbf6f00c25b6a2bed23c35eac6d62998ecdb338c
/*
 * 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 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * This file defines the domain environment values and the domain
 * database interface. The database is a single linked list of
 * structures containing domain type, name and SID information.
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <sys/list.h>
#include <stdio.h>
#include <strings.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <synch.h>
#include <pwd.h>
#include <grp.h>
#include <assert.h>

#include <smbsrv/smbinfo.h>
#include <smbsrv/string.h>
#include <smbsrv/smb_sid.h>
#include <smbsrv/libsmb.h>

#define SMB_DOMAINS_FILE    "domains"

#define SMB_DCACHE_UPDATE_WAIT  45  /* seconds */

/*
 * Domain cache states
 */
#define SMB_DCACHE_STATE_NONE       0
#define SMB_DCACHE_STATE_READY      1
#define SMB_DCACHE_STATE_UPDATING   2
#define SMB_DCACHE_STATE_DESTROYING 3

/*
 * Cache lock modes
 */
#define SMB_DCACHE_RDLOCK   0
#define SMB_DCACHE_WRLOCK   1

typedef struct smb_domain_cache {
    list_t      dc_cache;
    rwlock_t    dc_cache_lck;
    mutex_t     dc_mtx;
    cond_t      dc_cv;
    uint32_t    dc_state;
    uint32_t    dc_nops;
    char        dc_server[MAXHOSTNAMELEN];
} smb_domain_cache_t;

static smb_domain_cache_t smb_dcache;

static uint32_t smb_domain_add(smb_domain_type_t, smb_domain_t *);
static uint32_t smb_domain_add_local(void);
static uint32_t smb_domain_add_primary(uint32_t);
static void smb_domain_unlink(void);

static void smb_dcache_create(void);
static void smb_dcache_destroy(void);
static uint32_t smb_dcache_lock(int);
static void smb_dcache_unlock(void);
static void smb_dcache_remove(smb_domain_t *);
static uint32_t smb_dcache_add(smb_domain_t *);
static void smb_dcache_getdc(char *, size_t);
static void smb_dcache_setdc(char *);
static boolean_t smb_dcache_wait(void);
static uint32_t smb_dcache_updating(void);
static void smb_dcache_ready(void);

/*
 * domain cache one time initialization. This function should
 * only be called during service startup.
 *
 * Returns 0 on success and an error code on failure.
 */
int
smb_domain_init(uint32_t secmode)
{
    smb_domain_t di;
    int rc;

    smb_dcache_create();

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

    smb_domain_set_basic_info(NT_BUILTIN_DOMAIN_SIDSTR, "BUILTIN", "", &di);
    (void) smb_domain_add(SMB_DOMAIN_BUILTIN, &di);

    return (smb_domain_add_primary(secmode));
}

/*
 * Destroys the cache upon service termination
 */
void
smb_domain_fini(void)
{
    smb_dcache_destroy();
    smb_domain_unlink();
}

/*
 * Add a domain structure to domain cache. There is no checking
 * for duplicates.
 */
static uint32_t
smb_domain_add(smb_domain_type_t type, smb_domain_t *di)
{
    uint32_t res;

    if ((di == NULL) || (di->di_sid == NULL))
        return (SMB_DOMAIN_INVALID_ARG);

    if ((res = smb_dcache_lock(SMB_DCACHE_WRLOCK)) == SMB_DOMAIN_SUCCESS) {
        di->di_type = type;
        res = smb_dcache_add(di);
        smb_dcache_unlock();
    }

    return (res);
}

/*
 * Lookup a domain by its name. The passed name is the NETBIOS or fully
 * qualified DNS name or non-qualified DNS name.
 *
 * If the requested domain is found and given 'di' pointer is not NULL
 * it'll be filled with the domain information and B_TRUE is returned.
 * If the caller only needs to check a domain existence it can pass
 * NULL for 'di' and just check the return value.
 *
 * If the domain is not in the cache B_FALSE is returned.
 */
boolean_t
smb_domain_lookup_name(char *name, smb_domain_t *di)
{
    boolean_t found = B_FALSE;
    smb_domain_t *dcnode;
    char *p;

    bzero(di, sizeof (smb_domain_t));

    if (name == NULL || *name == '\0')
        return (B_FALSE);

    if (smb_dcache_lock(SMB_DCACHE_RDLOCK) != SMB_DOMAIN_SUCCESS)
        return (B_FALSE);

    dcnode = list_head(&smb_dcache.dc_cache);
    while (dcnode) {
        found = (smb_strcasecmp(dcnode->di_nbname, name, 0) == 0) ||
            (smb_strcasecmp(dcnode->di_fqname, name, 0) == 0);

        if (found) {
            if (di)
                *di = *dcnode;
            break;
        }

        if ((p = strchr(dcnode->di_fqname, '.')) != NULL) {
            *p = '\0';
            found = (smb_strcasecmp(dcnode->di_fqname, name,
                0) == 0);
            *p = '.';
            if (found) {
                if (di)
                    *di = *dcnode;
                break;
            }
        }

        dcnode = list_next(&smb_dcache.dc_cache, dcnode);
    }

    smb_dcache_unlock();
    return (found);
}

/*
 * Lookup a domain by its SID.
 *
 * If the requested domain is found and given 'di' pointer is not NULL
 * it'll be filled with the domain information and B_TRUE is returned.
 * If the caller only needs to check a domain existence it can pass
 * NULL for 'di' and just check the return value.
 *
 * If the domain is not in the cache B_FALSE is returned.
 */
boolean_t
smb_domain_lookup_sid(smb_sid_t *sid, smb_domain_t *di)
{
    boolean_t found = B_FALSE;
    smb_domain_t *dcnode;
    char sidstr[SMB_SID_STRSZ];

    bzero(di, sizeof (smb_domain_t));

    if (sid == NULL)
        return (B_FALSE);

    smb_sid_tostr(sid, sidstr);

    if (smb_dcache_lock(SMB_DCACHE_RDLOCK) != SMB_DOMAIN_SUCCESS)
        return (B_FALSE);

    dcnode = list_head(&smb_dcache.dc_cache);
    while (dcnode) {
        found = (strcmp(dcnode->di_sid, sidstr) == 0);
        if (found) {
            if (di)
                *di = *dcnode;
            break;
        }

        dcnode = list_next(&smb_dcache.dc_cache, dcnode);
    }

    smb_dcache_unlock();
    return (found);
}

/*
 * Lookup a domain by its type.
 *
 * If the requested domain is found and given 'di' pointer is not NULL
 * it'll be filled with the domain information and B_TRUE is returned.
 * If the caller only needs to check a domain existence it can pass
 * NULL for 'di' and just check the return value.
 *
 * If the domain is not in the cache B_FALSE is returned.
 */
boolean_t
smb_domain_lookup_type(smb_domain_type_t type, smb_domain_t *di)
{
    boolean_t found = B_FALSE;
    smb_domain_t *dcnode;

    bzero(di, sizeof (smb_domain_t));

    if (smb_dcache_lock(SMB_DCACHE_RDLOCK) != SMB_DOMAIN_SUCCESS)
        return (B_FALSE);

    dcnode = list_head(&smb_dcache.dc_cache);
    while (dcnode) {
        if (dcnode->di_type == type) {
            found = B_TRUE;
            if (di)
                *di = *dcnode;
            break;
        }

        dcnode = list_next(&smb_dcache.dc_cache, dcnode);
    }

    smb_dcache_unlock();
    return (found);
}

/*
 * Returns primary domain information plus the name of
 * the selected domain controller.
 */
boolean_t
smb_domain_getinfo(smb_domainex_t *dxi)
{
    boolean_t success;

    success = smb_domain_lookup_type(SMB_DOMAIN_PRIMARY, &dxi->d_primary);
    if (success)
        smb_dcache_getdc(dxi->d_dc, sizeof (dxi->d_dc));

    return (success);
}

/*
 * Transfer the cache to updating state.
 * In this state any request for reading the cache would
 * be blocked until the update is finished.
 */
uint32_t
smb_domain_start_update(void)
{
    return (smb_dcache_updating());
}

/*
 * Transfer the cache from updating to ready state.
 */
void
smb_domain_end_update(void)
{
    smb_dcache_ready();
}

/*
 * Updates the cache with given information for the primary
 * domain, possible trusted domains and the selected domain
 * controller.
 *
 * Before adding the new entries existing entries of type
 * primary and trusted will be removed from cache.
 */
void
smb_domain_update(smb_domainex_t *dxi)
{
    smb_domain_t *dcnode;
    int i;

    if (smb_dcache_lock(SMB_DCACHE_WRLOCK) != SMB_DOMAIN_SUCCESS)
        return;

    dcnode = list_head(&smb_dcache.dc_cache);
    while (dcnode) {
        if ((dcnode->di_type == SMB_DOMAIN_PRIMARY) ||
            (dcnode->di_type == SMB_DOMAIN_TRUSTED)) {
            smb_dcache_remove(dcnode);
            dcnode = list_head(&smb_dcache.dc_cache);
        } else {
            dcnode = list_next(&smb_dcache.dc_cache, dcnode);
        }
    }

    if (smb_dcache_add(&dxi->d_primary) == SMB_DOMAIN_SUCCESS) {
        for (i = 0; i < dxi->d_trusted.td_num; i++)
            (void) smb_dcache_add(&dxi->d_trusted.td_domains[i]);

        smb_dcache_setdc(dxi->d_dc);
    }

    smb_dcache_unlock();
}

/*
 * Write the list of domains to /var/run/smb/domains.
 */
void
smb_domain_save(void)
{
    char        fname[MAXPATHLEN];
    char        tag;
    smb_domain_t    *domain;
    FILE        *fp;
    struct passwd   *pwd;
    struct group    *grp;
    uid_t       uid;
    gid_t       gid;

    (void) snprintf(fname, MAXPATHLEN, "%s/%s",
        SMB_VARRUN_DIR, SMB_DOMAINS_FILE);

    if ((fp = fopen(fname, "w")) == NULL)
        return;

    pwd = getpwnam("root");
    grp = getgrnam("sys");
    uid = (pwd == NULL) ? 0 : pwd->pw_uid;
    gid = (grp == NULL) ? 3 : grp->gr_gid;

    (void) lockf(fileno(fp), F_LOCK, 0);
    (void) fchmod(fileno(fp), 0600);
    (void) fchown(fileno(fp), uid, gid);

    if (smb_dcache_lock(SMB_DCACHE_RDLOCK) != SMB_DOMAIN_SUCCESS)
        return;

    domain = list_head(&smb_dcache.dc_cache);
    while (domain) {
        switch (domain->di_type) {
        case SMB_DOMAIN_PRIMARY:
            tag = '*';
            break;

        case SMB_DOMAIN_TRUSTED:
        case SMB_DOMAIN_UNTRUSTED:
            tag = '-';
            break;

        case SMB_DOMAIN_LOCAL:
            tag = '.';
            break;
        default:
            domain = list_next(&smb_dcache.dc_cache, domain);
            continue;
        }

        (void) fprintf(fp, "[%c] [%s] [%s]\n",
            tag, domain->di_nbname, domain->di_sid);

        domain = list_next(&smb_dcache.dc_cache, domain);
    }

    smb_dcache_unlock();
    (void) lockf(fileno(fp), F_ULOCK, 0);
    (void) fclose(fp);
}

/*
 * List the domains in /var/run/smb/domains.
 */
void
smb_domain_show(void)
{
    char buf[MAXPATHLEN];
    char *p;
    FILE *fp;

    (void) snprintf(buf, MAXPATHLEN, "%s/%s",
        SMB_VARRUN_DIR, SMB_DOMAINS_FILE);

    if ((fp = fopen(buf, "r")) != NULL) {
        (void) lockf(fileno(fp), F_LOCK, 0);

        while (fgets(buf, MAXPATHLEN, fp) != NULL) {
            if ((p = strchr(buf, '\n')) != NULL)
                *p = '\0';
            (void) printf("%s\n", buf);
        }

        (void) lockf(fileno(fp), F_ULOCK, 0);
        (void) fclose(fp);
    }
}

void
smb_domain_set_basic_info(char *sid, char *nb_domain, char *fq_domain,
    smb_domain_t *di)
{
    if (sid == NULL || nb_domain == NULL || fq_domain == NULL ||
        di == NULL)
        return;

    (void) strlcpy(di->di_sid, sid, SMB_SID_STRSZ);
    (void) strlcpy(di->di_nbname, nb_domain, NETBIOS_NAME_SZ);
    (void) smb_strupr(di->di_nbname);
    (void) strlcpy(di->di_fqname, fq_domain, MAXHOSTNAMELEN);
    di->di_binsid = NULL;
}

void
smb_domain_set_dns_info(char *sid, char *nb_domain, char *fq_domain,
    char *forest, char *guid, smb_domain_t *di)
{
    if (di == NULL || forest == NULL || guid == NULL)
        return;

    smb_domain_set_basic_info(sid, nb_domain, fq_domain, di);
    (void) strlcpy(di->di_u.di_dns.ddi_forest, forest, MAXHOSTNAMELEN);
    (void) strlcpy(di->di_u.di_dns.ddi_guid, guid,
        UUID_PRINTABLE_STRING_LENGTH);
}

void
smb_domain_set_trust_info(char *sid, char *nb_domain, char *fq_domain,
    uint32_t trust_dir, uint32_t trust_type, uint32_t trust_attrs,
    smb_domain_t *di)
{
    smb_domain_trust_t *ti;

    if (di == NULL)
        return;

    di->di_type = SMB_DOMAIN_TRUSTED;
    ti = &di->di_u.di_trust;
    smb_domain_set_basic_info(sid, nb_domain, fq_domain, di);
    ti->dti_trust_direction = trust_dir;
    ti->dti_trust_type = trust_type;
    ti->dti_trust_attrs = trust_attrs;
}

/*
 * Remove the /var/run/smb/domains file.
 */
static void
smb_domain_unlink(void)
{
    char fname[MAXPATHLEN];

    (void) snprintf(fname, MAXPATHLEN, "%s/%s",
        SMB_VARRUN_DIR, SMB_DOMAINS_FILE);
    (void) unlink(fname);
}

/*
 * Add an entry for the local domain to the domain cache
 */
static uint32_t
smb_domain_add_local(void)
{
    char *lsidstr;
    char hostname[NETBIOS_NAME_SZ];
    char fq_name[MAXHOSTNAMELEN];
    smb_domain_t di;

    if ((lsidstr = smb_config_get_localsid()) == NULL)
        return (SMB_DOMAIN_NOMACHINE_SID);

    if (smb_getnetbiosname(hostname, NETBIOS_NAME_SZ) != 0) {
        free(lsidstr);
        return (SMB_DOMAIN_NOMACHINE_SID);
    }

    *fq_name = '\0';
    (void) smb_getfqhostname(fq_name, MAXHOSTNAMELEN);
    smb_domain_set_basic_info(lsidstr, hostname, fq_name, &di);
    (void) smb_domain_add(SMB_DOMAIN_LOCAL, &di);

    free(lsidstr);
    return (SMB_DOMAIN_SUCCESS);
}

/*
 * Add an entry for the primary domain to the domain cache
 */
static uint32_t
smb_domain_add_primary(uint32_t secmode)
{
    char sidstr[SMB_SID_STRSZ];
    char fq_name[MAXHOSTNAMELEN];
    char nb_name[NETBIOS_NAME_SZ];
    smb_domain_t di;
    int rc;

    if (secmode != SMB_SECMODE_DOMAIN)
        return (SMB_DOMAIN_SUCCESS);

    rc = smb_config_getstr(SMB_CI_DOMAIN_SID, sidstr, sizeof (sidstr));
    if (rc != SMBD_SMF_OK)
        return (SMB_DOMAIN_NODOMAIN_SID);

    rc = smb_config_getstr(SMB_CI_DOMAIN_NAME, nb_name, NETBIOS_NAME_SZ);
    if ((rc != SMBD_SMF_OK) || (*nb_name == '\0'))
        return (SMB_DOMAIN_NODOMAIN_NAME);

    (void) smb_getfqdomainname(fq_name, MAXHOSTNAMELEN);
    smb_domain_set_basic_info(sidstr, nb_name, fq_name, &di);
    (void) smb_domain_add(SMB_DOMAIN_PRIMARY, &di);
    return (SMB_DOMAIN_SUCCESS);
}

/*
 * Initialize the domain cache.
 * This function does not populate the cache.
 */
static void
smb_dcache_create(void)
{
    (void) mutex_lock(&smb_dcache.dc_mtx);
    if (smb_dcache.dc_state != SMB_DCACHE_STATE_NONE) {
        (void) mutex_unlock(&smb_dcache.dc_mtx);
        return;
    }

    list_create(&smb_dcache.dc_cache, sizeof (smb_domain_t),
        offsetof(smb_domain_t, di_lnd));

    smb_dcache.dc_nops = 0;
    *smb_dcache.dc_server = '\0';
    smb_dcache.dc_state = SMB_DCACHE_STATE_READY;
    (void) mutex_unlock(&smb_dcache.dc_mtx);
}

/*
 * Removes and frees all the cache entries
 */
static void
smb_dcache_flush(void)
{
    smb_domain_t *di;

    (void) rw_wrlock(&smb_dcache.dc_cache_lck);
    while ((di = list_head(&smb_dcache.dc_cache)) != NULL)
        smb_dcache_remove(di);
    (void) rw_unlock(&smb_dcache.dc_cache_lck);
}

/*
 * Destroys the cache.
 */
static void
smb_dcache_destroy(void)
{
    (void) mutex_lock(&smb_dcache.dc_mtx);
    if ((smb_dcache.dc_state == SMB_DCACHE_STATE_READY) ||
        (smb_dcache.dc_state == SMB_DCACHE_STATE_UPDATING)) {
        smb_dcache.dc_state = SMB_DCACHE_STATE_DESTROYING;
        while (smb_dcache.dc_nops > 0)
            (void) cond_wait(&smb_dcache.dc_cv,
                &smb_dcache.dc_mtx);

        smb_dcache_flush();
        list_destroy(&smb_dcache.dc_cache);

        smb_dcache.dc_state = SMB_DCACHE_STATE_NONE;
    }
    (void) mutex_unlock(&smb_dcache.dc_mtx);
}

/*
 * Lock the cache with the specified mode.
 * If the cache is in updating state and a read lock is
 * requested, the lock won't be granted until either the
 * update is finished or SMB_DCACHE_UPDATE_WAIT has passed.
 *
 * Whenever a lock is granted, the number of inflight cache
 * operations is incremented.
 */
static uint32_t
smb_dcache_lock(int mode)
{
    (void) mutex_lock(&smb_dcache.dc_mtx);
    switch (smb_dcache.dc_state) {
    case SMB_DCACHE_STATE_NONE:
    case SMB_DCACHE_STATE_DESTROYING:
        (void) mutex_unlock(&smb_dcache.dc_mtx);
        return (SMB_DOMAIN_INTERNAL_ERR);

    case SMB_DCACHE_STATE_UPDATING:
        if (mode == SMB_DCACHE_RDLOCK) {
            /*
             * Read operations should wait until the update
             * is completed.
             */
            if (!smb_dcache_wait()) {
                (void) mutex_unlock(&smb_dcache.dc_mtx);
                return (SMB_DOMAIN_INTERNAL_ERR);
            }
        }

    default:
        smb_dcache.dc_nops++;
        break;
    }
    (void) mutex_unlock(&smb_dcache.dc_mtx);

    /*
     * Lock has to be taken outside the mutex otherwise
     * there could be a deadlock
     */
    if (mode == SMB_DCACHE_RDLOCK)
        (void) rw_rdlock(&smb_dcache.dc_cache_lck);
    else
        (void) rw_wrlock(&smb_dcache.dc_cache_lck);

    return (SMB_DOMAIN_SUCCESS);
}

/*
 * Decrement the number of inflight operations and then unlock.
 */
static void
smb_dcache_unlock(void)
{
    (void) mutex_lock(&smb_dcache.dc_mtx);
    assert(smb_dcache.dc_nops > 0);
    smb_dcache.dc_nops--;
    (void) cond_broadcast(&smb_dcache.dc_cv);
    (void) mutex_unlock(&smb_dcache.dc_mtx);

    (void) rw_unlock(&smb_dcache.dc_cache_lck);
}

static uint32_t
smb_dcache_add(smb_domain_t *di)
{
    smb_domain_t *dcnode;

    if ((dcnode = malloc(sizeof (smb_domain_t))) == NULL)
        return (SMB_DOMAIN_NO_MEMORY);

    *dcnode = *di;
    dcnode->di_binsid = smb_sid_fromstr(dcnode->di_sid);
    if (dcnode->di_binsid == NULL) {
        free(dcnode);
        return (SMB_DOMAIN_NO_MEMORY);
    }

    list_insert_tail(&smb_dcache.dc_cache, dcnode);
    return (SMB_DOMAIN_SUCCESS);
}

static void
smb_dcache_remove(smb_domain_t *di)
{
    list_remove(&smb_dcache.dc_cache, di);
    smb_sid_free(di->di_binsid);
    free(di);
}

static void
smb_dcache_setdc(char *dc)
{
    (void) mutex_lock(&smb_dcache.dc_mtx);
    (void) strlcpy(smb_dcache.dc_server, dc, sizeof (smb_dcache.dc_server));
    (void) mutex_unlock(&smb_dcache.dc_mtx);
}

static void
smb_dcache_getdc(char *buf, size_t buflen)
{
    (void) mutex_lock(&smb_dcache.dc_mtx);
    (void) strlcpy(buf, smb_dcache.dc_server, buflen);
    (void) mutex_unlock(&smb_dcache.dc_mtx);
}

/*
 * Waits for SMB_DCACHE_UPDATE_WAIT seconds if cache is in
 * UPDATING state. Upon wake up returns true if cache is
 * ready to be used, otherwise it returns false.
 */
static boolean_t
smb_dcache_wait(void)
{
    timestruc_t to;
    int err;

    to.tv_sec = SMB_DCACHE_UPDATE_WAIT;
    to.tv_nsec = 0;
    while (smb_dcache.dc_state == SMB_DCACHE_STATE_UPDATING) {
        err = cond_reltimedwait(&smb_dcache.dc_cv,
            &smb_dcache.dc_mtx, &to);
        if (err == ETIME)
            break;
    }

    return (smb_dcache.dc_state == SMB_DCACHE_STATE_READY);
}

/*
 * Transfers the cache into UPDATING state, this will ensure
 * any read access to the cache will be stalled until the
 * update is finished. This is to avoid providing incomplete,
 * inconsistent or stale information.
 *
 * If another thread is already updating the cache, other
 * callers will wait until cache is no longer in UPDATING
 * state. The return code is decided based on the new
 * state of the cache.
 */
static uint32_t
smb_dcache_updating(void)
{
    uint32_t rc;

    (void) mutex_lock(&smb_dcache.dc_mtx);
    switch (smb_dcache.dc_state) {
    case SMB_DCACHE_STATE_READY:
        smb_dcache.dc_state = SMB_DCACHE_STATE_UPDATING;
        rc = SMB_DOMAIN_SUCCESS;
        break;

    case SMB_DCACHE_STATE_UPDATING:
        while (smb_dcache.dc_state == SMB_DCACHE_STATE_UPDATING)
            (void) cond_wait(&smb_dcache.dc_cv,
                &smb_dcache.dc_mtx);

        if (smb_dcache.dc_state == SMB_DCACHE_STATE_READY) {
            smb_dcache.dc_state = SMB_DCACHE_STATE_UPDATING;
            rc = SMB_DOMAIN_SUCCESS;
        } else {
            rc = SMB_DOMAIN_NO_CACHE;
        }
        break;

    case SMB_DCACHE_STATE_NONE:
    case SMB_DCACHE_STATE_DESTROYING:
        rc = SMB_DOMAIN_NO_CACHE;
        break;

    default:
        break;
    }

    (void) mutex_unlock(&smb_dcache.dc_mtx);
    return (rc);
}

/*
 * Transfers the cache from UPDATING to READY state.
 *
 * Nothing will happen if the cache is no longer available
 * or it is being destroyed.
 */
static void
smb_dcache_ready(void)
{
    (void) mutex_lock(&smb_dcache.dc_mtx);
    switch (smb_dcache.dc_state) {
    case SMB_DCACHE_STATE_UPDATING:
        smb_dcache.dc_state = SMB_DCACHE_STATE_READY;
        (void) cond_broadcast(&smb_dcache.dc_cv);
        break;

    case SMB_DCACHE_STATE_NONE:
    case SMB_DCACHE_STATE_DESTROYING:
        break;

    default:
        assert(0);
    }
    (void) mutex_unlock(&smb_dcache.dc_mtx);
}