Merge remote-tracking branch 'origin/master'

[unleashed/lotheac.git] / usr / src / lib / libsldap / common / ns_standalone.c

/*
 * 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.
 * Copyright 2012 Milan Jurik. All rights reserved.
 * Copyright 2012 Nexenta Systems, Inc. All rights reserved.
 */

#define __STANDALONE_MODULE__

#include <stdio.h>
#include <sys/types.h>
#include <stdlib.h>
#include <libintl.h>
#include <string.h>
#include <ctype.h>

#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <syslog.h>
#include <locale.h>
#include <errno.h>
#include <sys/time.h>

#include <arpa/inet.h>
#include <netdb.h>
#include <strings.h>

#include <thread.h>

#include <nsswitch.h>
#include <nss_dbdefs.h>
#include <nss.h>

#include "ns_cache_door.h"
#include "ns_internal.h"
#include "ns_connmgmt.h"

typedef enum {
        INFO_SERVER_JUST_INITED = -1,
        INFO_SERVER_UNKNOWN     = 0,
        INFO_SERVER_CONNECTING  = 1,
        INFO_SERVER_UP          = 2,
        INFO_SERVER_ERROR       = 3,
        INFO_SERVER_REMOVED     = 4
} dir_server_status_t;

typedef enum {
        INFO_STATUS_NEW         = 2,
        INFO_STATUS_OLD         = 3
} dir_server_info_t;

typedef struct dir_server {
        char                    *ip;
        char                    **controls;
        char                    **saslMech;
        dir_server_status_t     status;
        mutex_t                 updateStatus;
        dir_server_info_t       info;
} dir_server_t;

typedef struct dir_server_list {
        dir_server_t    **nsServers;

        rwlock_t        listDestroyLock;
} dir_server_list_t;

struct {
        /* The local list of the directory servers' root DSEs. */
        dir_server_list_t       *list;
        /* The flag indicating if libsldap is in the 'Standalone' mode. */
        int                     standalone;
        /*
         * The mutex ensuring that only one thread performs
         * the initialization of the list.
         */
        mutex_t                 listReplaceLock;
        /*
         * A flag indicating that a particular thread is
         * in the 'ldap_cachemgr' mode. It is stored by thread as
         * a thread specific data.
         */
        const int               initFlag;
        /*
         * A thread specific key storing
         * the the 'ldap_cachemgr' mode indicator.
         */
        thread_key_t            standaloneInitKey;
} dir_servers = {NULL, 0, DEFAULTMUTEX, '1'};

typedef struct switchDatabase {
        char *conf;
        uint32_t alloced;
} switch_database_t;

static thread_key_t switchConfigKey;

#pragma init(createStandaloneKey)

#define DONT_INCLUDE_ATTR_NAMES 0
#define INCLUDE_ATTR_NAMES      1
#define IS_PROFILE              1
#define NOT_PROFILE             0
/* INET6_ADDRSTRLEN + ":" + <5-digit port> + some round-up */
#define MAX_HOSTADDR_LEN (INET6_ADDRSTRLEN + 6 + 12)

static
void
switch_conf_disposer(void *data)
{
        switch_database_t *localData = (switch_database_t *)data;

        free(localData->conf);
        free(localData);
}

/*
 * This function initializes an indication that a thread obtaining a root DSE
 * will be switched to the 'ldap_cachemgr' mode. Within the thread libsldap
 * will not invoke the __s_api_requestServer function. Instead, the library
 * will establish a connection to the server specified by
 * the __ns_ldap_getRootDSE function.
 * Since  ldap_cachmgr can obtain a DUAProfile and root DSEs at the same time
 * and we do not want to affect a thread obtaining a DUAProfile,
 * the 'ldap_cachemgr' mode is thread private.
 * In addition, this function creates a key holding temporary configuration
 * for the "hosts" and "ipnodes" databases which is used by the "SKIPDB"
 * mechanism (__s_api_ip2hostname() & _s_api_hostname2ip()).
 */
static
void
createStandaloneKey()
{
        if (thr_keycreate(&dir_servers.standaloneInitKey, NULL) != 0) {
                syslog(LOG_ERR, gettext("libsldap: unable to create a thread "
                "key needed for sharing ldap connections"));
        }
        if (thr_keycreate(&switchConfigKey, switch_conf_disposer) != 0) {
                syslog(LOG_ERR, gettext("libsldap: unable to create a thread "
                    "key containing current nsswitch configuration"));
        }
}

/*
 * This function sets the 'ldap_cachemgr' mode indication.
 */
void
__s_api_setInitMode()
{
        (void) thr_setspecific(dir_servers.standaloneInitKey,
            (void *) &dir_servers.initFlag);
}

/*
 * This function unset the 'ldap_cachemgr' mode indication.
 */
void
__s_api_unsetInitMode()
{
        (void) thr_setspecific(dir_servers.standaloneInitKey, NULL);
}

/*
 * This function checks if the 'ldap_cachemgr' mode indication is set.
 */
int
__s_api_isInitializing() {
        int *flag = NULL;

        (void) thr_getspecific(dir_servers.standaloneInitKey, (void **) &flag);

        return (flag != NULL && *flag == dir_servers.initFlag);
}

/*
 * This function checks if the process runs in the 'Standalone' mode.
 * In this mode libsldap will check the local, process private list of root DSEs
 * instead of requesting them via a door call to ldap_cachemgr.
 */
int
__s_api_isStandalone()
{
        int     mode;

        (void) mutex_lock(&dir_servers.listReplaceLock);
        mode = dir_servers.standalone;
        (void) mutex_unlock(&dir_servers.listReplaceLock);

        return (mode);
}


static
int
remove_ldap(char *dst, char *src, int dst_buf_len)
{
        int i = 0;

        if (strlen(src) >= dst_buf_len)
                return (0);

        while (*src != '\0') {
                /* Copy up to one space from source. */
                if (isspace(*src)) {
                        dst[i++] = *src;
                        while (isspace(*src))
                                src++;
                }

                /* If not "ldap", just copy. */
                if (strncmp(src, "ldap", 4) != 0) {
                        while (!isspace(*src)) {
                                dst[i++] = *src++;
                                /* At the end of string? */
                                if (dst[i-1] == '\0')
                                        return (1);
                        }
                        /* Copy up to one space from source. */
                        if (isspace(*src)) {
                                dst[i++] = *src;
                                while (isspace(*src))
                                        src++;
                        }
                        /* Copy also the criteria section */
                        if (*src == '[')
                                while (*src != ']') {
                                        dst[i++] = *src++;
                                        /* Shouln't happen if format is right */
                                        if (dst[i-1] == '\0')
                                                return (1);
                                }
                }

                /* If next part is ldap, skip over it ... */
                if (strncmp(src, "ldap", 4) == 0) {
                        if (isspace(*(src+4)) || *(src+4) == '\0') {
                                src += 4;
                                while (isspace(*src))
                                        src++;
                                if (*src == '[') {
                                        while (*src++ != ']') {
                                                /*
                                                 * See comment above about
                                                 * correct format.
                                                 */
                                                if (*src == '\0') {
                                                        dst[i++] = '\0';
                                                        return (1);
                                                }
                                        }
                                }
                                while (isspace(*src))
                                        src++;
                        }
                }
                if (*src == '\0')
                        dst[i++] = '\0';
        }

        return (1);
}

static
char *
get_db(const char *db_name)
{
        char                    *ptr;
        switch_database_t       *hostService = NULL;
        FILE                    *fp = fopen(__NSW_CONFIG_FILE, "rF");
        char                    *linep, line[NSS_BUFSIZ];

        if (fp == NULL) {
                syslog(LOG_WARNING, gettext("libsldap: can not read %s"),
                    __NSW_CONFIG_FILE);
                return (NULL);
        }

        while ((linep = fgets(line, NSS_BUFSIZ, fp)) != NULL) {
                while (isspace(*linep)) {
                        ++linep;
                }
                if (*linep == '#') {
                        continue;
                }
                if (strncmp(linep, db_name, strlen(db_name)) != 0) {
                        continue;
                }
                if ((linep = strchr(linep, ':')) != NULL) {
                        if (linep[strlen(linep) - 1] == '\n') {
                                linep[strlen(linep) - 1] = '\0';
                        }

                        while (isspace(*++linep))
                                ;

                        if ((ptr = strchr(linep, '#')) != NULL) {
                                while (--ptr >= linep && isspace(*ptr))
                                        ;
                                *(ptr + 1) = '\0';
                        }

                        if (strlen(linep) == 0) {
                                continue;
                        }
                        break;
                }
        }

        (void) fclose(fp);

        if (linep == NULL) {
                syslog(LOG_WARNING,
                    gettext("libsldap: the %s database "
                    "is missing from %s"),
                    db_name,
                    __NSW_CONFIG_FILE);
                return (NULL);
        }

        (void) thr_getspecific(switchConfigKey, (void **) &hostService);
        if (hostService == NULL) {
                hostService = calloc(1, sizeof (switch_database_t));
                if (hostService == NULL) {
                        return (NULL);
                }
                (void) thr_setspecific(switchConfigKey, hostService);
        }

        /*
         * In a long-living process threads can perform several
         * getXbyY requests. And the windows between those requests
         * can be long. The nsswitch configuration can change from time
         * to time. So instead of allocating/freeing memory every time
         * the API is called, reallocate memory only when the current
         * configuration for the database being used is longer than
         * the previous one.
         */
        if (strlen(linep) >= hostService->alloced) {
                ptr = (char *)realloc((void *)hostService->conf,
                    strlen(linep) + 1);
                if (ptr == NULL) {
                        free((void *)hostService->conf);
                        hostService->conf = NULL;
                        hostService->alloced = 0;
                        return (NULL);
                }
                bzero(ptr, strlen(linep) + 1);
                hostService->conf = ptr;
                hostService->alloced = strlen(linep) + 1;
        }

        if (remove_ldap(hostService->conf, linep, hostService->alloced))
                return (hostService->conf);
        else
                return (NULL);
}

static
void
_initf_ipnodes(nss_db_params_t *p)
{
        char *services = get_db("ipnodes");

        p->name = NSS_DBNAM_IPNODES;
        p->flags |= NSS_USE_DEFAULT_CONFIG;
        p->default_config = services == NULL ? "" : services;
}

static
void
_initf_hosts(nss_db_params_t *p)
{
        char *services = get_db("hosts");

        p->name = NSS_DBNAM_HOSTS;
        p->flags |= NSS_USE_DEFAULT_CONFIG;
        p->default_config = services == NULL ? "" : services;
}

/*
 * This function is an analog of the standard gethostbyaddr_r()
 * function with an exception that it removes the 'ldap' back-end
 * (if any) from the host/ipnodes nsswitch's databases and then
 * looks up using remaining back-ends.
 */
static
struct hostent *
_filter_gethostbyaddr_r(const char *addr, int len, int type,
        struct hostent *result, char *buffer, int buflen,
        int *h_errnop)
{
        DEFINE_NSS_DB_ROOT(db_root_hosts);
        DEFINE_NSS_DB_ROOT(db_root_ipnodes);
        nss_XbyY_args_t arg;
        nss_status_t    res;
        int             (*str2ent)();
        void            (*nss_initf)();
        nss_db_root_t   *nss_db_root;
        int             dbop;

        switch (type) {
        case AF_INET:
                str2ent         = str2hostent;
                nss_initf       = _initf_hosts;
                nss_db_root     = &db_root_hosts;
                dbop            = NSS_DBOP_HOSTS_BYADDR;
                break;
        case AF_INET6:
                str2ent         = str2hostent6;
                nss_initf       = _initf_ipnodes;
                nss_db_root     = &db_root_ipnodes;
                dbop            = NSS_DBOP_IPNODES_BYADDR;
                break;
        default:
                return (NULL);
        }

        NSS_XbyY_INIT(&arg, result, buffer, buflen, str2ent);

        arg.key.hostaddr.addr   = addr;
        arg.key.hostaddr.len    = len;
        arg.key.hostaddr.type   = type;
        arg.stayopen            = 0;
        arg.h_errno             = NETDB_SUCCESS;

        res = nss_search(nss_db_root, nss_initf, dbop, &arg);
        arg.status = res;
        *h_errnop = arg.h_errno;
        return (struct hostent *)NSS_XbyY_FINI(&arg);
}

/*
 * This routine is an analog of gethostbyaddr_r().
 * But in addition __s_api_hostname2ip() performs the "LDAP SKIPDB" activity
 * prior to querying the name services.
 * If the buffer is not big enough to accommodate a returning data,
 * NULL is returned and h_errnop is set to TRY_AGAIN.
 */
struct hostent *
__s_api_hostname2ip(const char *name,
        struct hostent *result, char *buffer, int buflen,
        int *h_errnop)
{
        DEFINE_NSS_DB_ROOT(db_root_ipnodes);
        DEFINE_NSS_DB_ROOT(db_root_hosts);
        nss_XbyY_args_t arg;
        nss_status_t    res;
        struct in_addr  addr;
        struct in6_addr addr6;

        if (inet_pton(AF_INET, name, &addr) > 0) {
                if (buflen < strlen(name) + 1 +
                    sizeof (char *) * 2 + /* The h_aliases member */
                    sizeof (struct in_addr) +
                    sizeof (struct in_addr *) * 2) {
                        *h_errnop = TRY_AGAIN;
                        return (NULL);
                }

                result->h_addrtype = AF_INET;
                result->h_length = sizeof (struct in_addr);
                (void) strncpy(buffer, name, buflen);

                result->h_addr_list = (char **)ROUND_UP(
                    buffer + strlen(name) + 1,
                    sizeof (char *));
                result->h_aliases = (char **)ROUND_UP(result->h_addr_list,
                    sizeof (char *));
                result->h_aliases[0] = buffer;
                result->h_aliases[1] = NULL;
                bcopy(&addr,
                    buffer + buflen - sizeof (struct in_addr),
                    sizeof (struct in_addr));
                result->h_addr_list[0] = buffer + buflen -
                    sizeof (struct in_addr);
                result->h_addr_list[1] = NULL;
                result->h_aliases = result->h_addr_list;
                result->h_name = buffer;

                *h_errnop = NETDB_SUCCESS;
                return (result);
        }
        if (inet_pton(AF_INET6, name, &addr6) > 0) {
                if (buflen < strlen(name) + 1 +
                    sizeof (char *) * 2 + /* The h_aliases member */
                    sizeof (struct in6_addr) +
                    sizeof (struct in6_addr *) * 2) {
                        *h_errnop = TRY_AGAIN;
                        return (NULL);
                }

                result->h_addrtype = AF_INET6;
                result->h_length = sizeof (struct in6_addr);
                (void) strncpy(buffer, name, buflen);

                result->h_addr_list = (char **)ROUND_UP(
                    buffer + strlen(name) + 1,
                    sizeof (char *));
                result->h_aliases = (char **)ROUND_UP(result->h_addr_list,
                    sizeof (char *));
                result->h_aliases[0] = buffer;
                result->h_aliases[1] = NULL;
                bcopy(&addr6,
                    buffer + buflen - sizeof (struct in6_addr),
                    sizeof (struct in6_addr));
                result->h_addr_list[0] = buffer + buflen -
                    sizeof (struct in6_addr);
                result->h_addr_list[1] = NULL;
                result->h_aliases = result->h_addr_list;
                result->h_name = buffer;

                *h_errnop = NETDB_SUCCESS;
                return (result);
        }

        NSS_XbyY_INIT(&arg, result, buffer, buflen, str2hostent);

        arg.key.name = name;
        arg.stayopen = 0;
        arg.h_errno = NETDB_SUCCESS;

        res = nss_search(&db_root_ipnodes, _initf_ipnodes,
            NSS_DBOP_IPNODES_BYNAME, &arg);
        if (res == NSS_NOTFOUND || res == NSS_UNAVAIL) {
                arg.h_errno = NETDB_SUCCESS;
                res = nss_search(&db_root_hosts, _initf_hosts,
                    NSS_DBOP_HOSTS_BYNAME, &arg);
        }
        arg.status = res;
        *h_errnop = arg.h_errno;
        return ((struct hostent *)NSS_XbyY_FINI(&arg));
}

/*
 * Convert an IP to a host name.
 */
ns_ldap_return_code
__s_api_ip2hostname(char *ipaddr, char **hostname) {
        struct in_addr  in;
        struct in6_addr in6;
        struct hostent  *hp = NULL, hostEnt;
        char            buffer[NSS_BUFLEN_HOSTS];
        int             buflen = NSS_BUFLEN_HOSTS;
        char            *start = NULL,
                        *end = NULL,
                        delim = '\0';
        char            *port = NULL,
                        *addr = NULL;
        int             errorNum = 0,
                        len = 0;

        if (ipaddr == NULL || hostname == NULL)
                return (NS_LDAP_INVALID_PARAM);
        *hostname = NULL;
        if ((addr = strdup(ipaddr)) == NULL)
                return (NS_LDAP_MEMORY);

        if (addr[0] == '[') {
                /*
                 * Assume it's [ipv6]:port
                 * Extract ipv6 IP
                 */
                start = &addr[1];
                if ((end = strchr(addr, ']')) != NULL) {
                        *end = '\0';
                        delim = ']';
                        if (*(end + 1) == ':')
                                /* extract port */
                                port = end + 2;
                } else {
                        free(addr);
                        return (NS_LDAP_INVALID_PARAM);
                }
        } else if ((end = strchr(addr, ':')) != NULL) {
                /* assume it's ipv4:port */
                *end = '\0';
                delim = ':';
                start = addr;
                port = end + 1;
        } else
                /* No port */
                start = addr;


        if (inet_pton(AF_INET, start, &in) == 1) {
                /* IPv4 */
                hp = _filter_gethostbyaddr_r((char *)&in,
                    sizeof (in.s_addr),
                    AF_INET,
                    &hostEnt,
                    buffer,
                    buflen,
                    &errorNum);
                if (hp && hp->h_name) {
                        /* hostname + '\0' */
                        len = strlen(hp->h_name) + 1;
                        if (port)
                                /* ':' + port */
                                len += strlen(port) + 1;
                        if ((*hostname = malloc(len)) == NULL) {
                                free(addr);
                                return (NS_LDAP_MEMORY);
                        }

                        if (port)
                                (void) snprintf(*hostname, len, "%s:%s",
                                                hp->h_name, port);
                        else
                                (void) strlcpy(*hostname, hp->h_name, len);

                        free(addr);
                        return (NS_LDAP_SUCCESS);
                } else {
                        free(addr);
                        return (NS_LDAP_NOTFOUND);
                }
        } else if (inet_pton(AF_INET6, start, &in6) == 1) {
                /* IPv6 */
                hp = _filter_gethostbyaddr_r((char *)&in6,
                    sizeof (in6.s6_addr),
                    AF_INET6,
                    &hostEnt,
                    buffer,
                    buflen,
                    &errorNum);
                if (hp && hp->h_name) {
                        /* hostname + '\0' */
                        len = strlen(hp->h_name) + 1;
                        if (port)
                                /* ':' + port */
                                len += strlen(port) + 1;
                        if ((*hostname = malloc(len)) == NULL) {
                                free(addr);
                                return (NS_LDAP_MEMORY);
                        }

                        if (port)
                                (void) snprintf(*hostname, len, "%s:%s",
                                                hp->h_name, port);
                        else
                                (void) strlcpy(*hostname, hp->h_name, len);

                        free(addr);
                        return (NS_LDAP_SUCCESS);
                } else {
                        free(addr);
                        return (NS_LDAP_NOTFOUND);
                }
        } else {
                /*
                 * A hostname
                 * Return it as is
                 */
                if (end)
                        *end = delim;
                *hostname = addr;
                return (NS_LDAP_SUCCESS);
        }
}

/*
 * This function obtains data returned by an LDAP search request and puts it
 * in a string in the ldap_cachmgr(1) door call format.
 *
 * INPUT:
 *     ld - a pointer to an LDAP structure used for a search operation,
 *     result_msg - a pointer to an LDAPMessage returned by the search,
 *     include_names - if set to INCLUDE_ATTR_NAMES, the output buffer will
 *                     contain attribute names.
 *                     Otherwise, only values will be return.
 *
 * OUTPUT:
 *      a buffer containing server info in the following format:
 *         [<attribute name>=]value [DOORLINESEP [<attribute name>=]value ]...]
 *      Should be free'ed by the caller.
 */
static
ns_ldap_return_code
convert_to_door_line(LDAP* ld,
                LDAPMessage *result_msg,
                int include_names,
                int is_profile,
                char **door_line)
{
        uint32_t        total_length = 0, attr_len = 0, i;
        LDAPMessage     *e;
        char            *a, **vals;
        BerElement      *ber;
        int             seen_objectclass = 0, rewind = 0;

        if (!door_line) {
                return (NS_LDAP_INVALID_PARAM);
        }
        *door_line = NULL;

        if ((e = ldap_first_entry(ld, result_msg)) == NULL) {
                return (NS_LDAP_NOTFOUND);
        }

        /* calculate length of received data */
        for (a = ldap_first_attribute(ld, e, &ber);
            a != NULL;
            a = ldap_next_attribute(ld, e, ber)) {

                if ((vals = ldap_get_values(ld, e, a)) != NULL) {
                        for (i = 0; vals[i] != NULL; i++) {
                                total_length += (include_names ?
                                    strlen(a) : 0) +
                                    strlen(vals[i]) +
                                    strlen(DOORLINESEP) +1;
                        }
                        ldap_value_free(vals);
                }
                ldap_memfree(a);
        }
        if (ber != NULL) {
                ber_free(ber, 0);
        }

        if (total_length == 0) {
                return (NS_LDAP_NOTFOUND);
        }

        /* copy the data */
        /* add 1 for the last '\0' */
        *door_line  = (char *)malloc(total_length + 1);
        if (*door_line == NULL) {
                return (NS_LDAP_MEMORY);
        }

        /* make it an empty string first */
        **door_line = '\0';
        a = ldap_first_attribute(ld, e, &ber);
        while (a != NULL) {
                if (is_profile) {
                        /*
                         * If we're processing DUAConfigProfile, we need to make
                         * sure we put objectclass attribute first.
                         * __s_api_create_config_door_str depends on that.
                         */
                        if (seen_objectclass) {
                                if (strcasecmp(a, "objectclass") == 0) {
                                        /* Skip objectclass now. */
                                        a = ldap_next_attribute(ld, e, ber);
                                        continue;
                                }
                        } else {
                                if (strcasecmp(a, "objectclass") == 0) {
                                        seen_objectclass = 1;
                                        rewind = 1;
                                } else {
                                        /* Skip all but objectclass first. */
                                        a = ldap_next_attribute(ld, e, ber);
                                        continue;
                                }
                        }
                }

                if ((vals = ldap_get_values(ld, e, a)) != NULL) {
                        for (i = 0; vals[i] != NULL; i++) {
                                if (include_names) {
                                        attr_len += strlen(a);
                                }
                                attr_len += strlen(vals[i]) +
                                    strlen(DOORLINESEP) + 2;
                                if (include_names) {
                                        (void) snprintf(*door_line +
                                            strlen(*door_line),
                                            attr_len,
                                            "%s=%s%s",
                                            a, vals[i],
                                            DOORLINESEP);
                                } else {
                                        (void) snprintf(*door_line +
                                            strlen(*door_line),
                                            attr_len,
                                            "%s%s",
                                            vals[i],
                                            DOORLINESEP);
                                }
                        }
                        ldap_value_free(vals);
                }
                ldap_memfree(a);

                /* Rewind */
                if (rewind) {
                        if (ber != NULL) {
                                ber_free(ber, 0);
                        }
                        a = ldap_first_attribute(ld, e, &ber);
                        rewind = 0;
                } else {
                        a = ldap_next_attribute(ld, e, ber);
                }
        }
        if (ber != NULL) {
                ber_free(ber, 0);
        }

        if (e != result_msg) {
                (void) ldap_msgfree(e);
        }

        return (NS_LDAP_SUCCESS);
}

/*
 * This function looks up the base DN of a directory serving
 * a specified domain name.
 *
 * INPUT:
 *     ld - a pointer to an LDAP structure used for the search operation,
 *     domain_name - the name of a domain.
 *
 * OUTPUT:
 *     a buffer containing a directory's base DN found.
 *     Should be free'ed by the caller.
 */
static
ns_ldap_return_code
getDirBaseDN(LDAP *ld, const char *domain_name, char **dir_base_dn)
{
        struct timeval          tv = {NS_DEFAULT_SEARCH_TIMEOUT, 0};
        char                    *attrs[2], *DNlist, *rest, *ptr;
        char                    filter[BUFSIZ], *a = NULL;
        int                     ldap_rc;
        LDAPMessage             *resultMsg = NULL;
        ns_ldap_return_code     ret_code;

        /* Get the whole list of naming contexts residing on the server */
        attrs[0] = "namingcontexts";
        attrs[1] = NULL;
        ldap_rc = ldap_search_ext_s(ld, "", LDAP_SCOPE_BASE, "(objectclass=*)",
            attrs, 0, NULL, NULL, &tv, 0, &resultMsg);
        switch (ldap_rc) {
                /* If successful, the root DSE was found. */
                case LDAP_SUCCESS:
                        break;
                /*
                 * If the root DSE was not found, the server does
                 * not comply with the LDAP v3 protocol.
                 */
                default:
                        if (resultMsg) {
                                (void) ldap_msgfree(resultMsg);
                                resultMsg = NULL;
                        }

                        return (NS_LDAP_OP_FAILED);
        }

        if ((ret_code = convert_to_door_line(ld,
            resultMsg,
            DONT_INCLUDE_ATTR_NAMES,
            NOT_PROFILE,
            &DNlist)) != NS_LDAP_SUCCESS) {
                if (resultMsg) {
                        (void) ldap_msgfree(resultMsg);
                        resultMsg = NULL;
                }
                return (ret_code);
        }

        if (resultMsg) {
                (void) ldap_msgfree(resultMsg);
                resultMsg = NULL;
        }

        if (DNlist == NULL ||
            (ptr = strtok_r(DNlist, DOORLINESEP, &rest)) == NULL) {
                return (NS_LDAP_NOTFOUND);
        }
        attrs[0] = "dn";
        do {
                /*
                 * For each context try to find a NIS domain object
                 * which 'nisdomain' attribute's value matches the domain name
                 */
                (void) snprintf(filter,
                    BUFSIZ,
                    "(&(objectclass=nisDomainObject)"
                    "(nisdomain=%s))",
                    domain_name);
                ldap_rc = ldap_search_ext_s(ld,
                    ptr,
                    LDAP_SCOPE_SUBTREE,
                    filter,
                    attrs,
                    0,
                    NULL,
                    NULL,
                    &tv,
                    0,
                    &resultMsg);
                if (ldap_rc != LDAP_SUCCESS) {
                        if (resultMsg) {
                                (void) ldap_msgfree(resultMsg);
                                resultMsg = NULL;
                        }
                        continue;
                }
                if ((a = ldap_get_dn(ld, resultMsg)) != NULL) {
                        *dir_base_dn = strdup(a);
                        ldap_memfree(a);

                        if (resultMsg) {
                                (void) ldap_msgfree(resultMsg);
                                resultMsg = NULL;
                        }

                        if (!*dir_base_dn) {
                                free(DNlist);
                                return (NS_LDAP_MEMORY);
                        }
                        break;
                }

                if (resultMsg) {
                        (void) ldap_msgfree(resultMsg);
                        resultMsg = NULL;
                }
        } while (ptr = strtok_r(NULL, DOORLINESEP, &rest));

        free(DNlist);

        if (!*dir_base_dn) {
                return (NS_LDAP_NOTFOUND);
        }

        return (NS_LDAP_SUCCESS);
}

/*
 * This function parses the results of a search operation
 * requesting a DUAProfile.
 *
 * INPUT:
 *     ld - a pointer to an LDAP structure used for the search operation,
 *     dir_base_dn - the name of a directory's base DN,
 *     profile_name - the name of a DUAProfile to be obtained.
 *
 * OUTPUT:
 *      a buffer containing the DUAProfile in the following format:
 *        [<attribute name>=]value [DOORLINESEP [<attribute name>=]value ]...]
 *      Should be free'ed by the caller.
 */
static
ns_ldap_return_code
getDUAProfile(LDAP *ld,
                const char *dir_base_dn,
                const char *profile_name,
                char **profile)
{
        char                    searchBaseDN[BUFSIZ], filter[BUFSIZ];
        LDAPMessage             *resultMsg = NULL;
        struct timeval          tv = {NS_DEFAULT_SEARCH_TIMEOUT, 0};
        int                     ldap_rc;
        ns_ldap_return_code     ret_code;

        (void) snprintf(searchBaseDN, BUFSIZ, "ou=profile,%s", dir_base_dn);
        (void) snprintf(filter,
            BUFSIZ,
            _PROFILE_FILTER,
            _PROFILE1_OBJECTCLASS,
            _PROFILE2_OBJECTCLASS,
            profile_name);
        ldap_rc = ldap_search_ext_s(ld,
            searchBaseDN,
            LDAP_SCOPE_SUBTREE,
            filter,
            NULL,
            0,
            NULL,
            NULL,
            &tv,
            0,
            &resultMsg);

        switch (ldap_rc) {
                /* If successful, the DUA profile was found. */
                case LDAP_SUCCESS:
                        break;
                /*
                 * If the root DSE was not found, the server does
                 * not comply with the LDAP v3 protocol.
                 */
                default:
                        if (resultMsg) {
                                (void) ldap_msgfree(resultMsg);
                                resultMsg = NULL;
                        }

                        return (NS_LDAP_OP_FAILED);
        }

        ret_code = convert_to_door_line(ld,
            resultMsg,
            INCLUDE_ATTR_NAMES,
            IS_PROFILE,
            profile);
        if (resultMsg) {
                (void) ldap_msgfree(resultMsg);
                resultMsg = NULL;
        }
        return (ret_code);
}

/*
 * This function derives the directory's base DN from a provided domain name.
 *
 * INPUT:
 *     domain_name - the name of a domain to be converted into a base DN,
 *     buffer - contains the derived base DN,
 *     buf_len - the length of the buffer.
 *
 * OUTPUT:
 *     The function returns the address of the buffer or NULL.
 */
static
char *
domainname2baseDN(char *domain_name, char *buffer, uint16_t buf_len)
{
        char            *nextDC, *chr;
        uint16_t        i, length;

        if (!domain_name || !buffer || buf_len == 0) {
                return (NULL);
        }

        buffer[0] = '\0';
        nextDC = chr = domain_name;
        length = strlen(domain_name);
        for (i = 0; i < length + 1; ++i, ++chr) {
                /* Simply replace dots with "dc=" */
                if (*chr != '.' && *chr != '\0') {
                        continue;
                }
                *chr = '\0';
                if (strlcat(buffer, "dc=", buf_len) >= buf_len)
                        return (NULL);
                if (strlcat(buffer, nextDC, buf_len) >= buf_len)
                        return (NULL);
                if (i < length) {
                        /*
                         * The end of the domain name
                         * has not been reached yet
                         */
                        if (strlcat(buffer, ",", buf_len) >= buf_len)
                                return (NULL);
                        nextDC = chr + 1;
                        *chr = '.';
                }
        }

        return (buffer);
}

/*
 * This function obtains the directory's base DN and a DUAProfile
 * from a specified server.
 *
 * INPUT:
 *     server - a structure describing a server to connect to and
 *              a DUAProfile to be obtained from the server,
 *     cred - credentials to be used during establishing connections to
 *            the server.
 *
 * OUTPUT:
 *     dua_profile - a buffer containing the DUAProfile in the following format:
 *        [<attribute name>=]value [DOORLINESEP [<attribute name>=]value ]...]
 *     dir_base_dn - a buffer containing the base DN,
 *     errorp - an error object describing an error, if any.
 *
 *     All the output data structures should be free'ed by the caller.
 */
ns_ldap_return_code
__ns_ldap_getConnectionInfoFromDUA(const ns_dir_server_t *server,
        const ns_cred_t *cred,
        char **dua_profile,
        char **dir_base_dn,
        ns_ldap_error_t **errorp)
{
        char                    serverAddr[MAX_HOSTADDR_LEN];
        char                    *dirBaseDN = NULL, *duaProfile = NULL;
        ns_cred_t               default_cred;
        ns_ldap_return_code     ret_code;

        ns_config_t             *config_struct = __s_api_create_config();
        ConnectionID            sessionId = 0;
        Connection              *session = NULL;
        char                    errmsg[MAXERROR];
        char                    buffer[NSS_BUFLEN_HOSTS];
        ns_conn_user_t          *cu = NULL;

        if (errorp == NULL) {
                __s_api_destroy_config(config_struct);
                return (NS_LDAP_INVALID_PARAM);
        }

        *errorp = NULL;

        if (server == NULL) {
                __s_api_destroy_config(config_struct);
                return (NS_LDAP_INVALID_PARAM);
        }

        if (config_struct == NULL) {
                return (NS_LDAP_MEMORY);
        }

        /*
         * If no credentials are specified, try to establish a connection
         * as anonymous.
         */
        if (!cred) {
                default_cred.cred.unix_cred.passwd = NULL;
                default_cred.cred.unix_cred.userID = NULL;
                default_cred.auth.type = NS_LDAP_AUTH_NONE;
        }

        /* Now create a default LDAP configuration */

        (void) strncpy(buffer, server->server, sizeof (buffer));
        if (__ns_ldap_setParamValue(config_struct, NS_LDAP_SERVERS_P, buffer,
            errorp) != NS_LDAP_SUCCESS) {
                __s_api_destroy_config(config_struct);
                return (NS_LDAP_CONFIG);
        }

        /* Put together the address and the port specified by the user app. */
        if (server->port > 0) {
                (void) snprintf(serverAddr,
                    sizeof (serverAddr),
                    "%s:%hu",
                    buffer,
                    server->port);
        } else {
                (void) strncpy(serverAddr, buffer, sizeof (serverAddr));
        }

        /*
         * There is no default value for the 'Default Search Base DN' attribute.
         * Derive one from the domain name to make __s_api_crosscheck() happy.
         */
        if (domainname2baseDN(server->domainName ?
            server->domainName : config_struct->domainName,
            buffer, NSS_BUFLEN_HOSTS) == NULL) {
                (void) snprintf(errmsg,
                    sizeof (errmsg),
                    gettext("Can not convert %s into a base DN name"),
                    server->domainName ?
                    server->domainName : config_struct->domainName);
                MKERROR(LOG_ERR,
                    *errorp,
                    NS_LDAP_INTERNAL,
                    strdup(errmsg),
                    NS_LDAP_MEMORY);
                __s_api_destroy_config(config_struct);
                return (NS_LDAP_INTERNAL);
        }
        if (__ns_ldap_setParamValue(config_struct, NS_LDAP_SEARCH_BASEDN_P,
            buffer, errorp) != NS_LDAP_SUCCESS) {
                __s_api_destroy_config(config_struct);
                return (NS_LDAP_CONFIG);
        }

        if (__s_api_crosscheck(config_struct, errmsg, B_FALSE) != NS_SUCCESS) {
                __s_api_destroy_config(config_struct);
                return (NS_LDAP_CONFIG);
        }

        __s_api_init_config(config_struct);

        __s_api_setInitMode();

        cu = __s_api_conn_user_init(NS_CONN_USER_SEARCH, NULL, B_FALSE);
        if (cu == NULL) {
                return (NS_LDAP_INTERNAL);
        }

        if ((ret_code = __s_api_getConnection(serverAddr,
            NS_LDAP_NEW_CONN,
            cred ? cred : &default_cred,
            &sessionId,
            &session,
            errorp,
            0,
            0,
            cu)) != NS_LDAP_SUCCESS) {
                __s_api_conn_user_free(cu);
                __s_api_unsetInitMode();
                return (ret_code);
        }

        __s_api_unsetInitMode();

        if ((ret_code = getDirBaseDN(session->ld,
            server->domainName ?
            server->domainName :
            config_struct->domainName,
            &dirBaseDN)) != NS_LDAP_SUCCESS) {
                (void) snprintf(errmsg,
                    sizeof (errmsg),
                    gettext("Can not find the "
                    "nisDomainObject for domain %s\n"),
                    server->domainName ?
                    server->domainName : config_struct->domainName);
                MKERROR(LOG_ERR,
                    *errorp,
                    ret_code,
                    strdup(errmsg),
                    NS_LDAP_MEMORY);
                __s_api_conn_user_free(cu);
                DropConnection(sessionId, NS_LDAP_NEW_CONN);
                return (ret_code);
        }

        /*
         * And here obtain a DUAProfile which will be used
         * as a real configuration.
         */
        if ((ret_code = getDUAProfile(session->ld,
            dirBaseDN,
            server->profileName ?
            server->profileName : "default",
            &duaProfile)) != NS_LDAP_SUCCESS) {
                (void) snprintf(errmsg,
                    sizeof (errmsg),
                    gettext("Can not find the "
                    "%s DUAProfile\n"),
                    server->profileName ?
                    server->profileName : "default");
                MKERROR(LOG_ERR,
                    *errorp,
                    ret_code,
                    strdup(errmsg),
                    NS_LDAP_MEMORY);
                __s_api_conn_user_free(cu);
                DropConnection(sessionId, NS_LDAP_NEW_CONN);
                return (ret_code);
        }

        if (dir_base_dn) {
                *dir_base_dn = dirBaseDN;
        } else {
                free(dirBaseDN);
        }

        if (dua_profile) {
                *dua_profile = duaProfile;
        } else {
                free(duaProfile);
        }

        __s_api_conn_user_free(cu);
        DropConnection(sessionId, NS_LDAP_NEW_CONN);

        return (NS_LDAP_SUCCESS);
}

/*
 * This function obtains the root DSE from a specified server.
 *
 * INPUT:
 *     server_addr - an adress of a server to be connected to.
 *
 * OUTPUT:
 *     root_dse - a buffer containing the root DSE in the following format:
 *          [<attribute name>=]value [DOORLINESEP [<attribute name>=]value ]...]
 *        For example: ( here | used as DOORLINESEP for visual purposes)
 *          supportedControl=1.1.1.1|supportedSASLmechanisms=EXTERNAL
 *        Should be free'ed by the caller.
 */
ns_ldap_return_code
__ns_ldap_getRootDSE(const char *server_addr,
                char **root_dse,
                ns_ldap_error_t **errorp,
                int anon_fallback)
{
        char                    errmsg[MAXERROR];
        ns_ldap_return_code     ret_code;

        ConnectionID            sessionId = 0;
        Connection              *session = NULL;

        struct timeval          tv = {NS_DEFAULT_SEARCH_TIMEOUT, 0};
        char                    *attrs[3];
        int                     ldap_rc, ldaperrno = 0;
        LDAPMessage             *resultMsg = NULL;
        void                    **paramVal = NULL;

        ns_cred_t               anon;
        ns_conn_user_t          *cu = NULL;

        if (errorp == NULL) {
                return (NS_LDAP_INVALID_PARAM);
        }

        *errorp = NULL;

        if (!root_dse) {
                return (NS_LDAP_INVALID_PARAM);
        }

        if (!server_addr) {
                return (NS_LDAP_INVALID_PARAM);
        }

        __s_api_setInitMode();

        cu = __s_api_conn_user_init(NS_CONN_USER_SEARCH, NULL, B_FALSE);
        if (cu == NULL) {
                return (NS_LDAP_INTERNAL);
        }

        /*
         * All the credentials will be taken from the current
         * libsldap configuration.
         */
        if ((ret_code = __s_api_getConnection(server_addr,
            NS_LDAP_NEW_CONN,
            NULL,
            &sessionId,
            &session,
            errorp,
            0,
            0,
            cu)) != NS_LDAP_SUCCESS) {
                /* Fallback to anonymous mode is disabled. Stop. */
                if (anon_fallback == 0) {
                        syslog(LOG_WARNING,
                            gettext("libsldap: can not get the root DSE from "
                            " the %s server: %s. "
                            "Falling back to anonymous disabled.\n"),
                            server_addr,
                            errorp && *errorp && (*errorp)->message ?
                            (*errorp)->message : "");
                        if (errorp != NULL && *errorp != NULL) {
                                (void) __ns_ldap_freeError(errorp);
                        }
                        __s_api_unsetInitMode();
                        return (ret_code);
                }

                /*
                 * Fallback to anonymous, non-SSL mode for backward
                 * compatibility reasons. This mode should only be used when
                 * this function (__ns_ldap_getRootDSE) is called from
                 * ldap_cachemgr(8).
                 */
                syslog(LOG_WARNING,
                    gettext("libsldap: Falling back to anonymous, non-SSL"
                    " mode for __ns_ldap_getRootDSE. %s\n"),
                    errorp && *errorp && (*errorp)->message ?
                    (*errorp)->message : "");

                /* Setup the anon credential for anonymous connection. */
                (void) memset(&anon, 0, sizeof (ns_cred_t));
                anon.auth.type = NS_LDAP_AUTH_NONE;

                if (*errorp != NULL) {
                        (void) __ns_ldap_freeError(errorp);
                }
                *errorp = NULL;

                ret_code = __s_api_getConnection(server_addr,
                    NS_LDAP_NEW_CONN,
                    &anon,
                    &sessionId,
                    &session,
                    errorp,
                    0,
                    0,
                    cu);

                if (ret_code != NS_LDAP_SUCCESS) {
                        __s_api_conn_user_free(cu);
                        __s_api_unsetInitMode();
                        return (ret_code);
                }
        }

        __s_api_unsetInitMode();

        /* get search timeout value */
        (void) __ns_ldap_getParam(NS_LDAP_SEARCH_TIME_P, &paramVal, errorp);
        if (paramVal != NULL && *paramVal != NULL) {
                tv.tv_sec = **((int **)paramVal);
                (void) __ns_ldap_freeParam(&paramVal);
        }
        if (*errorp != NULL) {
                (void) __ns_ldap_freeError(errorp);
        }

        /* Get root DSE from the server specified by the caller. */
        attrs[0] = "supportedControl";
        attrs[1] = "supportedsaslmechanisms";
        attrs[2] = NULL;
        ldap_rc = ldap_search_ext_s(session->ld,
            "",
            LDAP_SCOPE_BASE,
            "(objectclass=*)",
            attrs,
            0,
            NULL,
            NULL,
            &tv,
            0,
            &resultMsg);

        if (ldap_rc != LDAP_SUCCESS) {
                /*
                 * If the root DSE was not found, the server does
                 * not comply with the LDAP v3 protocol.
                 */
                (void) ldap_get_option(session->ld,
                    LDAP_OPT_ERROR_NUMBER,
                    &ldaperrno);
                (void) snprintf(errmsg,
                    sizeof (errmsg),
                    gettext(ldap_err2string(ldaperrno)));
                MKERROR(LOG_ERR,
                    *errorp,
                    NS_LDAP_OP_FAILED,
                    strdup(errmsg),
                    NS_LDAP_MEMORY);

                if (resultMsg) {
                        (void) ldap_msgfree(resultMsg);
                        resultMsg = NULL;
                }

                __s_api_conn_user_free(cu);
                DropConnection(sessionId, NS_LDAP_NEW_CONN);
                return (NS_LDAP_OP_FAILED);
        }
        __s_api_conn_user_free(cu);

        ret_code = convert_to_door_line(session->ld,
            resultMsg,
            INCLUDE_ATTR_NAMES,
            NOT_PROFILE,
            root_dse);
        if (ret_code == NS_LDAP_NOTFOUND) {
                (void) snprintf(errmsg,
                    sizeof (errmsg),
                    gettext("No root DSE data "
                    "for server %s returned."),
                    server_addr);
                MKERROR(LOG_ERR,
                    *errorp,
                    NS_LDAP_NOTFOUND,
                    strdup(errmsg),
                    NS_LDAP_MEMORY);
        }

        if (resultMsg) {
                (void) ldap_msgfree(resultMsg);
                resultMsg = NULL;
        }

        DropConnection(sessionId, NS_LDAP_NEW_CONN);

        return (ret_code);
}

/*
 * This function destroys the local list of root DSEs. The input parameter is
 * a pointer to the list to be erased.
 * The type of the pointer passed to this function should be
 * (dir_server_list_t *).
 */
static
void *
disposeOfOldList(void *param)
{
        dir_server_list_t       *old_list = (dir_server_list_t *)param;
        long                    i = 0, j;

        (void) rw_wrlock(&old_list->listDestroyLock);
        /* Destroy the old list */
        while (old_list->nsServers[i]) {
                free(old_list->nsServers[i]->ip);
                j = 0;
                while (old_list->nsServers[i]->controls &&
                    old_list->nsServers[i]->controls[j]) {
                        free(old_list->nsServers[i]->controls[j]);
                        ++j;
                }
                free(old_list->nsServers[i]->controls);
                j = 0;
                while (old_list->nsServers[i]->saslMech &&
                    old_list->nsServers[i]->saslMech[j]) {
                        free(old_list->nsServers[i]->saslMech[j]);
                        ++j;
                }
                free(old_list->nsServers[i]->saslMech);
                ++i;
        }
        /*
         * All the structures pointed by old_list->nsServers were allocated
         * in one chunck. The nsServers[0] pointer points to the beginning
         * of that chunck.
         */
        free(old_list->nsServers[0]);
        free(old_list->nsServers);
        (void) rw_unlock(&old_list->listDestroyLock);
        (void) rwlock_destroy(&old_list->listDestroyLock);
        free(old_list);

        return (NULL);
}

/*
 * This function cancels the Standalone mode and destroys the list of root DSEs.
 */
void
__ns_ldap_cancelStandalone(void)
{
        dir_server_list_t       *old_list;

        (void) mutex_lock(&dir_servers.listReplaceLock);
        dir_servers.standalone = 0;
        if (!dir_servers.list) {
                (void) mutex_unlock(&dir_servers.listReplaceLock);
                return;
        }
        old_list = dir_servers.list;
        dir_servers.list = NULL;
        (void) mutex_unlock(&dir_servers.listReplaceLock);

        (void) disposeOfOldList(old_list);
}


static
void*
create_ns_servers_entry(void *param)
{
#define CHUNK_SIZE 16

        dir_server_t            *server = (dir_server_t *)param;
        ns_ldap_return_code     *retCode = calloc(1,
            sizeof (ns_ldap_return_code));
        uint32_t                sc_counter = 0, sm_counter = 0;
        uint32_t                sc_mem_blocks = 1, sm_mem_blocks = 1;
        char                    *rootDSE = NULL, *attr, *val, *rest, **ptr;
        ns_ldap_error_t         *error = NULL;

        if (retCode == NULL) {
                return (NULL);
        }

        /*
         * We call this function in non anon-fallback mode because we
         * want the whole procedure to fail as soon as possible to
         * indicate there are problems with connecting to the server.
         */
        *retCode = __ns_ldap_getRootDSE(server->ip,
            &rootDSE,
            &error,
            SA_ALLOW_FALLBACK);

        if (*retCode == NS_LDAP_MEMORY) {
                free(retCode);
                return (NULL);
        }

        /*
         * If the root DSE can not be obtained, log an error and keep the
         * server.
         */
        if (*retCode != NS_LDAP_SUCCESS) {
                server->status = INFO_SERVER_ERROR;
                syslog(LOG_WARNING,
                    gettext("libsldap (\"standalone\" mode): "
                    "can not obtain the root DSE from %s. %s"),
                    server->ip,
                    error && error->message ? error->message : "");
                if (error) {
                        (void) __ns_ldap_freeError(&error);
                }
                return (retCode);
        }

        /* Get the first attribute of the root DSE. */
        attr = strtok_r(rootDSE, DOORLINESEP, &rest);
        if (attr == NULL) {
                free(rootDSE);
                server->status = INFO_SERVER_ERROR;
                syslog(LOG_WARNING,
                    gettext("libsldap (\"standalone\" mode): "
                    "the root DSE from %s is empty or corrupted."),
                    server->ip);
                *retCode = NS_LDAP_INTERNAL;
                return (retCode);
        }

        server->controls = (char **)calloc(CHUNK_SIZE, sizeof (char *));
        server->saslMech = (char **)calloc(CHUNK_SIZE, sizeof (char *));
        if (server->controls == NULL || server->saslMech == NULL) {
                free(rootDSE);
                free(retCode);
                return (NULL);
        }

        do {
                if ((val = strchr(attr, '=')) == NULL) {
                        continue;
                }
                ++val;

                if (strncasecmp(attr,
                    _SASLMECHANISM,
                    _SASLMECHANISM_LEN) == 0) {
                        if (sm_counter == CHUNK_SIZE * sm_mem_blocks - 1) {
                                ptr = (char **)reallocarray(server->saslMech,
                                    CHUNK_SIZE * ++sm_mem_blocks,
                                    sizeof (char *));
                                if (ptr == NULL) {
                                        *retCode = NS_LDAP_MEMORY;
                                        break;
                                }
                                bzero((char *)ptr +
                                    (sm_counter + 1) *
                                    sizeof (char *),
                                    CHUNK_SIZE *
                                    sm_mem_blocks *
                                    sizeof (char *) -
                                    (sm_counter + 1) *
                                    sizeof (char *));
                                server->saslMech = ptr;
                        }
                        server->saslMech[sm_counter] = strdup(val);
                        if (server->saslMech[sm_counter] == NULL) {
                                *retCode = NS_LDAP_MEMORY;
                                break;
                        }
                        ++sm_counter;
                        continue;
                }
                if (strncasecmp(attr,
                    _SUPPORTEDCONTROL,
                    _SUPPORTEDCONTROL_LEN) == 0) {
                        if (sc_counter == CHUNK_SIZE * sc_mem_blocks - 1) {
                                ptr = (char **)reallocarray(server->controls,
                                    CHUNK_SIZE * ++sc_mem_blocks,
                                    sizeof (char *));
                                if (ptr == NULL) {
                                        *retCode = NS_LDAP_MEMORY;
                                        break;
                                }
                                bzero((char *)ptr +
                                    (sc_counter + 1) *
                                    sizeof (char *),
                                    CHUNK_SIZE *
                                    sc_mem_blocks *
                                    sizeof (char *) -
                                    (sc_counter + 1) *
                                    sizeof (char *));
                                server->controls = ptr;
                        }

                        server->controls[sc_counter] = strdup(val);
                        if (server->controls[sc_counter] == NULL) {
                                *retCode = NS_LDAP_MEMORY;
                                break;
                        }
                        ++sc_counter;
                        continue;
                }

        } while (attr = strtok_r(NULL, DOORLINESEP, &rest));

        free(rootDSE);

        if (*retCode == NS_LDAP_MEMORY) {
                free(retCode);
                return (NULL);
        }

        server->controls[sc_counter] = NULL;
        server->saslMech[sm_counter] = NULL;

        server->status = INFO_SERVER_UP;

        return (retCode);
#undef CHUNK_SIZE
}


/*
 * This function creates a new local list of root DSEs from all the servers
 * mentioned in the DUAProfile (or local NS BEC) and returns
 * a pointer to the list.
 */
static
ns_ldap_return_code
createDirServerList(dir_server_list_t **new_list,
                ns_ldap_error_t **errorp)
{
        char                    **serverList;
        ns_ldap_return_code     retCode = NS_LDAP_SUCCESS;
        dir_server_t            *tmpSrvArray;
        long                    srvListLength, i;
        thread_t                *thrPool, thrID;
        void                    *status = NULL;

        if (errorp == NULL) {
                return (NS_LDAP_INVALID_PARAM);
        }

        *errorp = NULL;

        if (new_list == NULL) {
                return (NS_LDAP_INVALID_PARAM);
        }

        retCode = __s_api_getServers(&serverList, errorp);
        if (retCode != NS_LDAP_SUCCESS || serverList == NULL) {
                return (retCode);
        }

        for (i = 0; serverList[i]; ++i) {
                ;
        }
        srvListLength = i;

        thrPool = calloc(srvListLength, sizeof (thread_t));
        if (thrPool == NULL) {
                __s_api_free2dArray(serverList);
                return (NS_LDAP_MEMORY);
        }

        *new_list = (dir_server_list_t *)calloc(1,
            sizeof (dir_server_list_t));
        if (*new_list == NULL) {
                __s_api_free2dArray(serverList);
                free(thrPool);
                return (NS_LDAP_MEMORY);
        }
        (void) rwlock_init(&(*new_list)->listDestroyLock, USYNC_THREAD, NULL);

        (*new_list)->nsServers = (dir_server_t **)calloc(srvListLength + 1,
            sizeof (dir_server_t *));
        if ((*new_list)->nsServers == NULL) {
                free(*new_list);
                *new_list = NULL;
                __s_api_free2dArray(serverList);
                free(thrPool);
                return (NS_LDAP_MEMORY);
        }

        /*
         * Allocate a set of dir_server_t structures as an array,
         * with one alloc call and then initialize the nsServers pointers
         * with the addresses of the array's members.
         */
        tmpSrvArray = (dir_server_t *)calloc(srvListLength,
            sizeof (dir_server_t));
        for (i = 0; i < srvListLength; ++i) {
                (*new_list)->nsServers[i] = &tmpSrvArray[i];

                (*new_list)->nsServers[i]->info = INFO_STATUS_NEW;
                (void) mutex_init(&(*new_list)->nsServers[i]->updateStatus,
                    USYNC_THREAD,
                    NULL);

                (*new_list)->nsServers[i]->ip = strdup(serverList[i]);
                if ((*new_list)->nsServers[i]->ip == NULL) {
                        retCode = NS_LDAP_MEMORY;
                        break;
                }

                (*new_list)->nsServers[i]->status = INFO_SERVER_CONNECTING;

                switch (thr_create(NULL,
                    0,
                    create_ns_servers_entry,
                    (*new_list)->nsServers[i],
                    0,
                    &thrID)) {
                case EAGAIN:
                        (*new_list)->nsServers[i]->status =
                            INFO_SERVER_ERROR;
                        continue;
                case ENOMEM:
                        (*new_list)->nsServers[i]->status =
                            INFO_SERVER_ERROR;
                        continue;
                default:
                        thrPool[i] = thrID;
                        continue;
                }
        }

        for (i = 0; i < srvListLength; ++i) {
                if (thrPool[i] != 0 &&
                    thr_join(thrPool[i], NULL, &status) == 0) {
                        if (status == NULL) {
                                /*
                                 * Some memory allocation problems occured. Just
                                 * ignore the server and hope there will be some
                                 * other good ones.
                                 */
                                (*new_list)->nsServers[i]->status =
                                    INFO_SERVER_ERROR;
                        }
                        free(status);
                }
        }

        __s_api_free2dArray(serverList);
        free(thrPool);

        if (retCode == NS_LDAP_MEMORY) {
                (void) disposeOfOldList(*new_list);
                return (NS_LDAP_MEMORY);
        }

        return (NS_LDAP_SUCCESS);
}

/*
 * This functions replaces the local list of root DSEs with a new one and starts
 * a thread destroying the old list. There is no need for other threads to wait
 * until the old list will be destroyed.
 * Since it is possible that more than one thread can start creating the list,
 * this function should be protected by mutexes to be sure that only one thread
 * performs the initialization.
 */
static
ns_ldap_return_code
initGlobalList(ns_ldap_error_t **error)
{
        dir_server_list_t       *new_list, *old_list;
        ns_ldap_return_code     ret_code;
        thread_t                tid;

        ret_code = createDirServerList(&new_list, error);
        if (ret_code != NS_LDAP_SUCCESS) {
                return (ret_code);
        }

        old_list = dir_servers.list;
        dir_servers.list = new_list;

        if (old_list) {
                (void) thr_create(NULL,
                    0,
                    disposeOfOldList,
                    old_list,
                    THR_DETACHED,
                    &tid);
        }

        return (NS_LDAP_SUCCESS);
}

static
struct {
        char *authMech;
        ns_auth_t auth;
} authArray[] = {{"none", {NS_LDAP_AUTH_NONE,
                        NS_LDAP_TLS_NONE,
                        NS_LDAP_SASL_NONE,
                        NS_LDAP_SASLOPT_NONE}},
                {"simple", {NS_LDAP_AUTH_SIMPLE,
                        NS_LDAP_TLS_NONE,
                        NS_LDAP_SASL_NONE,
                        NS_LDAP_SASLOPT_NONE}},
                {"tls:simple", {NS_LDAP_AUTH_TLS,
                        NS_LDAP_TLS_SIMPLE,
                        NS_LDAP_SASL_NONE,
                        NS_LDAP_SASLOPT_NONE}},
                {"tls:sasl/CRAM-MD5", {NS_LDAP_AUTH_TLS,
                        NS_LDAP_TLS_SASL,
                        NS_LDAP_SASL_CRAM_MD5,
                        NS_LDAP_SASLOPT_NONE}},
                {"tls:sasl/DIGEST-MD5", {NS_LDAP_AUTH_TLS,
                        NS_LDAP_TLS_SASL,
                        NS_LDAP_SASL_DIGEST_MD5,
                        NS_LDAP_SASLOPT_NONE}},
                {"sasl/CRAM-MD5", {NS_LDAP_AUTH_SASL,
                        NS_LDAP_TLS_SASL,
                        NS_LDAP_SASL_CRAM_MD5,
                        NS_LDAP_SASLOPT_NONE}},
                {"sasl/DIGEST-MD5", {NS_LDAP_AUTH_SASL,
                        NS_LDAP_TLS_SASL,
                        NS_LDAP_SASL_DIGEST_MD5,
                        NS_LDAP_SASLOPT_NONE}},
                {"sasl/GSSAPI", {NS_LDAP_AUTH_SASL,
                        NS_LDAP_TLS_SASL,
                        NS_LDAP_SASL_GSSAPI,
                        NS_LDAP_SASLOPT_PRIV | NS_LDAP_SASLOPT_INT}},
                {NULL, {NS_LDAP_AUTH_NONE,
                        NS_LDAP_TLS_NONE,
                        NS_LDAP_SASL_NONE,
                        NS_LDAP_SASLOPT_NONE}}};

ns_ldap_return_code
__ns_ldap_initAuth(const char *auth_mech,
                ns_auth_t *auth,
                ns_ldap_error_t **errorp)
{
        uint32_t        i;
        char            errmsg[MAXERROR];

        if (auth_mech == NULL) {
                (void) snprintf(errmsg,
                    sizeof (errmsg),
                    gettext("Invalid authentication method specified\n"));
                MKERROR(LOG_WARNING,
                    *errorp,
                    NS_LDAP_INTERNAL,
                    strdup(errmsg),
                    NS_LDAP_MEMORY);
                return (NS_LDAP_INTERNAL);
        }

        for (i = 0; authArray[i].authMech != NULL; ++i) {
                if (strcasecmp(auth_mech, authArray[i].authMech) == 0) {
                        *auth = authArray[i].auth;
                        return (NS_LDAP_SUCCESS);
                }
        }

        (void) snprintf(errmsg,
            sizeof (errmsg),
            gettext("Invalid authentication method specified\n"));
        MKERROR(LOG_WARNING,
            *errorp,
            NS_LDAP_INTERNAL,
            strdup(errmsg),
            NS_LDAP_MEMORY);
        return (NS_LDAP_INTERNAL);
}

/*
 * This function "informs" libsldap that a client application has specified
 * a directory to use. The function obtains a DUAProfile, credentials,
 * and naming context. During all further operations on behalf
 * of the application requested a standalone schema libsldap will use
 * the information obtained by __ns_ldap_initStandalone() instead of
 * door_call(3C)ing ldap_cachemgr(8).
 *
 * INPUT:
 *     sa_conf - a structure describing where and in which way to obtain all
 *               the configuration describing how to communicate to
 *               a choosen LDAP directory,
 *     errorp - an error object describing an error occured.
 */
ns_ldap_return_code
__ns_ldap_initStandalone(const ns_standalone_conf_t *sa_conf,
                        ns_ldap_error_t **errorp) {

        ns_cred_t       user_cred = {{NS_LDAP_AUTH_NONE,
                                        NS_LDAP_TLS_NONE,
                                        NS_LDAP_SASL_NONE,
                                        NS_LDAP_SASLOPT_NONE},
                                        NULL,
                                        {NULL, NULL}};
        char            *dua_profile = NULL;
        char            errmsg[MAXERROR];
        ns_config_t     *cfg;
        int             ret_code;

        if (sa_conf->SA_BIND_DN == NULL && sa_conf->SA_BIND_PWD != NULL ||
            sa_conf->SA_BIND_DN != NULL && sa_conf->SA_BIND_PWD == NULL) {
                (void) snprintf(errmsg,
                    sizeof (errmsg),
                    gettext("Bind DN and bind password"
                    " must both be provided\n"));
                MKERROR(LOG_ERR,
                    *errorp,
                    NS_CONFIG_NOTLOADED,
                    strdup(errmsg),
                    NS_LDAP_MEMORY);
                return (NS_LDAP_INTERNAL);
        }

        switch (sa_conf->type) {
        case NS_LDAP_SERVER:
                if (sa_conf->SA_BIND_DN != NULL) {
                        user_cred.cred.unix_cred.userID = sa_conf->SA_BIND_DN;
                        user_cred.auth.type = NS_LDAP_AUTH_SIMPLE;
                }

                if (sa_conf->SA_BIND_PWD != NULL) {
                        user_cred.cred.unix_cred.passwd = sa_conf->SA_BIND_PWD;
                }

                if (sa_conf->SA_AUTH != NULL) {
                        user_cred.auth.type = sa_conf->SA_AUTH->type;
                        user_cred.auth.tlstype = sa_conf->SA_AUTH->tlstype;
                        user_cred.auth.saslmech = sa_conf->SA_AUTH->saslmech;
                        user_cred.auth.saslopt = sa_conf->SA_AUTH->saslopt;
                }

                if (sa_conf->SA_CERT_PATH != NULL) {
                        user_cred.hostcertpath = sa_conf->SA_CERT_PATH;
                }

                ret_code = __ns_ldap_getConnectionInfoFromDUA(
                    &sa_conf->ds_profile.server,
                    &user_cred,
                    &dua_profile,
                    NULL,
                    errorp);
                if (ret_code != NS_LDAP_SUCCESS) {
                        return (ret_code);
                }

                cfg = __s_api_create_config_door_str(dua_profile, errorp);
                if (cfg == NULL) {
                        free(dua_profile);
                        return (NS_LDAP_CONFIG);
                }

                if (sa_conf->SA_CERT_PATH != NULL) {
                        char            *certPathAttr;
                        ParamIndexType  type;

                        switch (cfg->version) {
                        case NS_LDAP_V1:
                                certPathAttr = "NS_LDAP_CERT_PATH";
                                break;
                        default:        /* Version 2 */
                                certPathAttr = "NS_LDAP_HOST_CERTPATH";
                                break;
                        }

                        if (__s_api_get_versiontype(cfg,
                                                certPathAttr,
                                                &type) == 0 &&
                            (ret_code = __ns_ldap_setParamValue(cfg,
                                                type,
                                                sa_conf->SA_CERT_PATH,
                                                errorp)) != NS_LDAP_SUCCESS) {
                                __s_api_destroy_config(cfg);
                                return (ret_code);
                        }
                }

                if (sa_conf->SA_BIND_DN != NULL &&
                    sa_conf->SA_BIND_PWD != NULL) {
                        char *authMethods;

                        authMethods = __s_api_strValue(cfg, NS_LDAP_AUTH_P,
                            NS_FILE_FMT);
                        if (authMethods != NULL &&
                            strstr(authMethods, "sasl/GSSAPI") != NULL) {
                                /*
                                 * The received DUAProfile specifies
                                 * sasl/GSSAPI as an auth. mechanism.
                                 * The bind DN and password will be
                                 * ignored.
                                 */
                                syslog(LOG_INFO, gettext("sasl/GSSAPI will be "
                                    "used as an authentication method. "
                                    "The bind DN and password will "
                                    "be ignored.\n"));
                                free(authMethods);
                                break;
                        }

                        free(authMethods);

                        if (__ns_ldap_setParamValue(cfg,
                                                NS_LDAP_BINDDN_P,
                                                sa_conf->SA_BIND_DN,
                                                errorp) != NS_LDAP_SUCCESS) {
                                __s_api_destroy_config(cfg);
                                return (NS_LDAP_CONFIG);
                        }

                        if (__ns_ldap_setParamValue(cfg,
                            NS_LDAP_BINDPASSWD_P,
                            sa_conf->SA_BIND_PWD,
                            errorp) != NS_LDAP_SUCCESS) {
                                __s_api_destroy_config(cfg);
                                return (NS_LDAP_CONFIG);
                        }
                }

                break;
        default:        /* NS_CACHEMGR */
                return (NS_LDAP_SUCCESS);
        }

        __s_api_init_config(cfg);
        /* Connection management should use the new config now. */
        __s_api_reinit_conn_mgmt_new_config(cfg);
        __ns_ldap_setServer(TRUE);

        (void) mutex_lock(&dir_servers.listReplaceLock);
        if ((ret_code = initGlobalList(errorp)) != NS_SUCCESS) {
                (void) mutex_unlock(&dir_servers.listReplaceLock);
                return (ret_code);
        }
        dir_servers.standalone = 1;
        (void) mutex_unlock(&dir_servers.listReplaceLock);

        return (NS_LDAP_SUCCESS);
}

/*
 * INPUT:
 *     serverAddr is the address of a server and
 *     request is one of the following:
 *     NS_CACHE_NEW:    get a new server address, addr is ignored.
 *     NS_CACHE_NORESP: get the next one, remove addr from list.
 *     NS_CACHE_NEXT:   get the next one, keep addr on list.
 *     NS_CACHE_WRITE:  get a non-replica server, if possible, if not, same
 *                      as NS_CACHE_NEXT.
 *     addrType:
 *     NS_CACHE_ADDR_IP: return server address as is, this is default.
 *     NS_CACHE_ADDR_HOSTNAME: return server addess as FQDN format, only
 *                             self credential case requires such format.
 * OUTPUT:
 *     ret
 *
 *     a structure of type ns_server_info_t containing the server address
 *     or name, server controls and supported SASL mechanisms.
 *     NOTE: Caller should allocate space for the structure and free
 *     all the space allocated by the function for the information contained
 *     in the structure.
 *
 *     error - an error object describing an error, if any.
 */
ns_ldap_return_code
__s_api_findRootDSE(const char *request,
                const char *serverAddr,
                const char *addrType,
                ns_server_info_t *ret,
                ns_ldap_error_t **error)
{
        dir_server_list_t       *current_list = NULL;
        ns_ldap_return_code     ret_code;
        long                    i = 0;
        int                     matched = FALSE;
        dir_server_t            *server = NULL;
        char                    errmsg[MAXERROR];

        (void) mutex_lock(&dir_servers.listReplaceLock);
        if (dir_servers.list == NULL) {
                (void) mutex_unlock(&dir_servers.listReplaceLock);
                (void) snprintf(errmsg,
                    sizeof (errmsg),
                    gettext("The list of root DSEs is empty: "
                    "the Standalone mode was not properly initialized"));
                MKERROR(LOG_ERR,
                    *error,
                    NS_CONFIG_NOTLOADED,
                    strdup(errmsg),
                    NS_LDAP_MEMORY);
                return (NS_LDAP_INTERNAL);
        }

        current_list = dir_servers.list;
        (void) rw_rdlock(&current_list->listDestroyLock);
        (void) mutex_unlock(&dir_servers.listReplaceLock);

        /*
         * The code below is mostly the clone of the
         * ldap_cachemgr::cachemgr_getldap.c::getldap_get_serverInfo() function.
         * Currently we have two different server lists: one is maintained
         * by libsldap ('standalone' mode), the other is in ldap_cachemgr
         * (a part of its standard functionality).
         */

        /*
         * If NS_CACHE_NEW, or the server info is new,
         * starts from the beginning of the list.
         */
        (void) mutex_lock(&current_list->nsServers[0]->updateStatus);
        if (strcmp(request, NS_CACHE_NEW) == 0 ||
            current_list->nsServers[0]->info == INFO_STATUS_NEW) {
                matched = TRUE;
        }
        (void) mutex_unlock(&current_list->nsServers[i]->updateStatus);

        for (i = 0; current_list->nsServers[i]; ++i) {
                /*
                 * Lock the updateStatus mutex to
                 * make sure the server status stays the same
                 * while the data is being processed.
                 */
                if (matched == FALSE &&
                    strcmp(current_list->nsServers[i]->ip,
                    serverAddr) == 0) {
                        matched = TRUE;
                        if (strcmp(request, NS_CACHE_NORESP) == 0) {

                                /*
                                 * if the server has already been removed,
                                 * don't bother.
                                 */
                                (void) mutex_lock(&current_list->
                                    nsServers[i]->updateStatus);
                                if (current_list->nsServers[i]->status ==
                                    INFO_SERVER_REMOVED) {
                                        (void) mutex_unlock(&current_list->
                                            nsServers[i]->
                                            updateStatus);
                                        continue;
                                }
                                (void) mutex_unlock(&current_list->
                                    nsServers[i]->
                                    updateStatus);

                                /*
                                 * if the information is new,
                                 * give this server one more chance.
                                 */
                                (void) mutex_lock(&current_list->
                                    nsServers[i]->
                                    updateStatus);
                                if (current_list->nsServers[i]->info ==
                                    INFO_STATUS_NEW &&
                                    current_list->nsServers[i]->status  ==
                                    INFO_SERVER_UP) {
                                        server = current_list->nsServers[i];
                                        (void) mutex_unlock(&current_list->
                                            nsServers[i]->
                                            updateStatus);
                                        break;
                                } else {
                                        /*
                                         * it is recommended that
                                         * before removing the
                                         * server from the list,
                                         * the server should be
                                         * contacted one more time
                                         * to make sure that it is
                                         * really unavailable.
                                         * For now, just trust the client
                                         * (i.e., the sldap library)
                                         * that it knows what it is
                                         * doing and would not try
                                         * to mess up the server
                                         * list.
                                         */
                                        current_list->nsServers[i]->status =
                                            INFO_SERVER_REMOVED;
                                        (void) mutex_unlock(&current_list->
                                            nsServers[i]->
                                            updateStatus);
                                        continue;
                                }
                        } else {
                                /*
                                 * req == NS_CACHE_NEXT or NS_CACHE_WRITE
                                 */
                                continue;
                        }
                }

                if (matched) {
                        if (strcmp(request, NS_CACHE_WRITE) == 0) {
                                /*
                                 * ldap_cachemgr checks here if the server
                                 * is not a non-replica server (a server
                                 * of type INFO_RW_WRITEABLE). But currently
                                 * it considers all the servers in its list
                                 * as those.
                                 */
                                (void) mutex_lock(&current_list->
                                    nsServers[i]->
                                    updateStatus);
                                if (current_list->nsServers[i]->status  ==
                                    INFO_SERVER_UP) {
                                        (void) mutex_unlock(&current_list->
                                            nsServers[i]->
                                            updateStatus);
                                        server = current_list->nsServers[i];
                                        break;
                                }
                        } else {
                                (void) mutex_lock(&current_list->
                                    nsServers[i]->
                                    updateStatus);
                                if (current_list->nsServers[i]->status ==
                                    INFO_SERVER_UP) {
                                        (void) mutex_unlock(&current_list->
                                            nsServers[i]->
                                            updateStatus);
                                        server = current_list->nsServers[i];
                                        break;
                                }
                        }

                        (void) mutex_unlock(&current_list->
                            nsServers[i]->
                            updateStatus);
                }
        }

        if (server == NULL) {
                (void) rw_unlock(&current_list->listDestroyLock);
                (void) snprintf(errmsg,
                    sizeof (errmsg),
                    gettext("No servers are available"));
                MKERROR(LOG_ERR,
                    *error,
                    NS_CONFIG_NOTLOADED,
                    strdup(errmsg),
                    NS_LDAP_MEMORY);
                return (NS_LDAP_NOTFOUND);
        }

        (void) mutex_lock(&server->updateStatus);
        server->info = INFO_STATUS_OLD;
        (void) mutex_unlock(&server->updateStatus);

        if (ret == NULL) {
                (void) rw_unlock(&current_list->listDestroyLock);
                return (NS_LDAP_SUCCESS);
        }

        if (strcmp(addrType, NS_CACHE_ADDR_HOSTNAME) == 0) {
                ret_code = __s_api_ip2hostname(server->ip, &ret->serverFQDN);
                if (ret_code != NS_LDAP_SUCCESS) {
                        (void) snprintf(errmsg,
                            sizeof (errmsg),
                            gettext("The %s address "
                            "can not be resolved into "
                            "a host name. Returning "
                            "the address as it is."),
                            server->ip);
                        MKERROR(LOG_ERR,
                            *error,
                            NS_CONFIG_NOTLOADED,
                            strdup(errmsg),
                            NS_LDAP_MEMORY);
                        return (NS_LDAP_INTERNAL);
                }
        }

        ret->server = strdup(server->ip);

        ret->controls = __s_api_cp2dArray(server->controls);
        ret->saslMechanisms = __s_api_cp2dArray(server->saslMech);

        (void) rw_unlock(&current_list->listDestroyLock);

        return (NS_LDAP_SUCCESS);
}

/*
 * This function iterates through the list of the configured LDAP servers
 * and "pings" those which are marked as removed or if any error occurred
 * during the previous receiving of the server's root DSE. If the
 * function is able to reach such a server and get its root DSE, it
 * marks the server as on-line. Otherwise, the server's status is set
 * to "Error".
 * For each server the function tries to connect to, it fires up
 * a separate thread and then waits until all the treads finish.
 * The function returns NS_LDAP_INTERNAL if the Standalone mode was not
 * initialized or was canceled prior to an invocation of
 * __ns_ldap_pingOfflineServers().
 */
ns_ldap_return_code
__ns_ldap_pingOfflineServers(void)
{
        dir_server_list_t       *current_list = NULL;
        ns_ldap_return_code     retCode = NS_LDAP_SUCCESS;
        long                    srvListLength, i = 0;
        thread_t                *thrPool, thrID;
        void                    *status = NULL;

        (void) mutex_lock(&dir_servers.listReplaceLock);
        if (dir_servers.list == NULL) {
                (void) mutex_unlock(&dir_servers.listReplaceLock);
                return (NS_LDAP_INTERNAL);
        }

        current_list = dir_servers.list;
        (void) rw_wrlock(&current_list->listDestroyLock);
        (void) mutex_unlock(&dir_servers.listReplaceLock);

        while (current_list->nsServers[i] != NULL) {
                ++i;
        }
        srvListLength = i;

        thrPool = calloc(srvListLength, sizeof (thread_t));
        if (thrPool == NULL) {
                (void) rw_unlock(&current_list->listDestroyLock);
                return (NS_LDAP_MEMORY);
        }

        for (i = 0; i < srvListLength; ++i) {
                if (current_list->nsServers[i]->status != INFO_SERVER_REMOVED &&
                    current_list->nsServers[i]->status != INFO_SERVER_ERROR) {
                        continue;
                }
                current_list->nsServers[i]->status = INFO_SERVER_CONNECTING;
                current_list->nsServers[i]->info = INFO_STATUS_NEW;

                __s_api_free2dArray(current_list->nsServers[i]->controls);
                current_list->nsServers[i]->controls = NULL;
                __s_api_free2dArray(current_list->nsServers[i]->saslMech);
                current_list->nsServers[i]->saslMech = NULL;

                switch (thr_create(NULL,
                    0,
                    create_ns_servers_entry,
                    current_list->nsServers[i],
                    0,
                    &thrID)) {
                case EAGAIN:
                        current_list->nsServers[i]->status = INFO_SERVER_ERROR;
                        continue;
                case ENOMEM:
                        current_list->nsServers[i]->status = INFO_SERVER_ERROR;
                        retCode = NS_LDAP_MEMORY;
                        break;
                default:
                        thrPool[i] = thrID;
                        continue;
                }
                /* A memory allocation error has occured */
                break;

        }

        for (i = 0; i < srvListLength; ++i) {
                if (thrPool[i] != 0 &&
                    thr_join(thrPool[i], NULL, &status) == 0) {
                        if (status == NULL) {
                                current_list->nsServers[i]->status =
                                    INFO_SERVER_ERROR;
                                retCode = NS_LDAP_MEMORY;
                        }
                        free(status);
                }
        }

        (void) rw_unlock(&current_list->listDestroyLock);

        free(thrPool);

        return (retCode);
}