proto_ldap_sync_ldap.c

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/*
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */
 
/**
 * $Id: 38f2d8280a2713a5b8ba7e043afd2dfac8f18be9 $
 * @file proto_ldap_sync_ldap.c
 * @brief LDAP sync handler.
 *
 * @copyright 2022 Network RADIUS SAS (legal@networkradius.com)
 */
USES_APPLE_DEPRECATED_API
 
#define LOG_PREFIX "proto_ldap_sync_ldap"
 
#include <freeradius-devel/protocol/freeradius/freeradius.internal.h>
#include <freeradius-devel/internal/internal.h>
#include <freeradius-devel/server/protocol.h>
#include <freeradius-devel/server/request.h>
#include <freeradius-devel/io/listen.h>
#include <freeradius-devel/io/application.h>
#include <freeradius-devel/unlang/call.h>
#include <freeradius-devel/util/dbuff.h>
#include <freeradius-devel/ldap/base.h>
#include <freeradius-devel/ldap/conf.h>
 
#include "proto_ldap_sync_ldap.h"
#include "rfc4533.h"
#include "persistent_search.h"
#include "active_directory.h"
 
static fr_internal_encode_ctx_t encode_ctx = { .allow_name_only = true };
 
extern fr_app_io_t proto_ldap_sync_ldap;
extern fr_app_io_t proto_ldap_sync_child;
 
static conf_parser_t const proto_ldap_sync_ldap_config[] = {
        /*
         *      LDAP server definition
         */
        { FR_CONF_OFFSET_FLAGS("server", CONF_FLAG_REQUIRED, proto_ldap_sync_ldap_t, server) },
 
        /*
         *      Common LDAP conf parsers
         */
        FR_LDAP_COMMON_CONF(proto_ldap_sync_ldap_t),
 
        /*
         *      Network tunable parameters
         */
        { FR_CONF_OFFSET_IS_SET("recv_buff", FR_TYPE_UINT32, 0, proto_ldap_sync_ldap_t, recv_buff) },
        { FR_CONF_OFFSET("max_outstanding", proto_ldap_sync_ldap_t, max_outstanding), .dflt = "65536" },
 
        CONF_PARSER_TERMINATOR
};
 
static fr_dict_t const *dict_ldap_sync;
static fr_dict_t const *dict_freeradius;
 
extern fr_dict_autoload_t proto_ldap_sync_ldap_dict[];
fr_dict_autoload_t proto_ldap_sync_ldap_dict[] = {
        { .out = &dict_ldap_sync, .proto = "ldap" },
        { .out = &dict_freeradius, .proto = "freeradius" },
        { NULL }
};
 
static fr_dict_attr_t const *attr_ldap_sync_packet_id;
static fr_dict_attr_t const *attr_ldap_sync_cookie;
static fr_dict_attr_t const *attr_ldap_sync_entry_dn;
static fr_dict_attr_t const *attr_ldap_sync_entry_uuid;
static fr_dict_attr_t const *attr_ldap_sync_orig_dn;
static fr_dict_attr_t const *attr_ldap_sync_root_dn;
static fr_dict_attr_t const *attr_packet_type;
static fr_dict_attr_t const *attr_ldap_sync_base_dn;
 
extern fr_dict_attr_autoload_t proto_ldap_sync_ldap_dict_attr[];
fr_dict_attr_autoload_t proto_ldap_sync_ldap_dict_attr[] = {
        { .out = &attr_ldap_sync_packet_id, .name = "Sync-Packet-ID", .type = FR_TYPE_UINT32, .dict = &dict_ldap_sync },
        { .out = &attr_ldap_sync_cookie, .name = "LDAP-Sync.Cookie", .type = FR_TYPE_OCTETS, .dict = &dict_ldap_sync },
        { .out = &attr_ldap_sync_entry_dn, .name = "LDAP-Sync.Entry-DN", .type = FR_TYPE_STRING, .dict = &dict_ldap_sync },
        { .out = &attr_ldap_sync_entry_uuid, .name = "LDAP-Sync.Entry-UUID", .type = FR_TYPE_OCTETS, .dict = &dict_ldap_sync },
        { .out = &attr_ldap_sync_orig_dn, .name = "LDAP-Sync.Original-DN", .type = FR_TYPE_STRING, .dict = &dict_ldap_sync },
        { .out = &attr_ldap_sync_root_dn, .name = "LDAP-Sync.Directory-Root-DN", .type = FR_TYPE_STRING, .dict = &dict_ldap_sync },
        { .out = &attr_packet_type, .name = "Packet-Type", .type = FR_TYPE_UINT32, .dict = &dict_ldap_sync },
        { .out = &attr_ldap_sync_base_dn, .name = "LDAP-Sync-Base-DN", .type = FR_TYPE_STRING, .dict = &dict_freeradius },
        { NULL }
};
 
extern global_lib_autoinst_t const *proto_ldap_sync_ldap_lib[];
global_lib_autoinst_t const *proto_ldap_sync_ldap_lib[] = {
        &fr_libldap_global_config,
        GLOBAL_LIB_TERMINATOR
};
 
/** Operations performed on entries
 */
fr_table_num_sorted_t const sync_op_table[] = {
        { L("add"),                     SYNC_OP_ADD                     },
        { L("delete"),                  SYNC_OP_DELETE                  },
        { L("modify"),                  SYNC_OP_MODIFY                  },
        { L("present"),                 SYNC_OP_PRESENT                 },
};
size_t sync_op_table_len = NUM_ELEMENTS(sync_op_table);
 
/** Context used when looking up Directory types
 */
typedef struct {
        fr_listen_t             *main_listen;
        fr_listen_t             *child_listen;
        fr_connection_t         *conn;
        int                     msgid;
} proto_ldap_dir_ctx;
 
/** Context for "load Cookie" retry timed event
 */
typedef struct {
        proto_ldap_sync_ldap_thread_t   *thread;
        proto_ldap_sync_ldap_t const    *inst;
        size_t                          sync_no;
} proto_ldap_cookie_load_retry_ctx;
 
/** Compare two sync state structures on msgid
 *
 * @param[in] one first sync to compare.
 * @param[in] two second sync to compare.
 * @return CMP(one, two)
 */
int8_t sync_state_cmp(void const *one, void const *two)
{
        sync_state_t const *a = one, *b = two;
 
        return CMP(a->msgid, b->msgid);
}
 
/** Tell the remote server to stop the sync
 *
 * Terminates the search informing the remote server that we no longer want to receive results
 * for this sync.  A RFC 4511 abandon request is used to inform the server.
 *
 * This allows individual syncs to be stopped without destroying the underlying connection.
 *
 * Removes the sync's msgid from the tree of msgids associated with the connection.
 *
 * @param[in] sync to abandon.
 * @return 0
 */
static int sync_state_free(sync_state_t *sync)
{
        fr_ldap_connection_t    *conn = talloc_get_type_abort(sync->conn, fr_ldap_connection_t);
        fr_rb_tree_t            *tree = talloc_get_type_abort(conn->uctx, fr_rb_tree_t);
 
        DEBUG3("Abandoning sync base dn \"%s\", filter \"%s\"", sync->config->base_dn, sync->config->filter);
 
        trigger_exec(NULL, sync->config->cs, "ldap_sync.stop", true, &sync->trigger_args);
 
        if (!sync->conn->handle) return 0;      /* Handled already closed? */
 
        /*
         *      Tell the remote server to stop sending results
         */
        if (sync->msgid >= 0) ldap_abandon_ext(sync->conn->handle, sync->msgid, NULL, NULL);
        fr_rb_delete(tree, &(sync_state_t){.msgid = sync->msgid});
 
        return 0;
}
 
/** Allocate a sync state
 *
 * @param[in] ctx       to allocate the sync state in.
 * @param[in] conn      which the sync will run on.
 * @param[in] inst      module instance for the sync.
 * @param[in] sync_no   number of the sync in the array of configs.
 * @param[in] config    for the sync.
 * @return new sync state.
 */
sync_state_t *sync_state_alloc(TALLOC_CTX *ctx, fr_ldap_connection_t *conn, proto_ldap_sync_t const *inst,
                               size_t sync_no, sync_config_t const *config)
{
        sync_state_t            *sync;
        fr_pair_t               *vp;
 
        MEM(sync = talloc_zero(ctx, sync_state_t));
        sync->conn = conn;
        sync->inst = inst;
        sync->config = config;
        sync->sync_no = sync_no;
        sync->phase = SYNC_PHASE_INIT;
 
        fr_dlist_talloc_init(&sync->pending, sync_packet_ctx_t, entry);
 
        /*
         *      Create arguments to pass to triggers
         */
        fr_pair_list_init(&sync->trigger_args);
        fr_pair_list_append_by_da_len(sync, vp, &sync->trigger_args, attr_ldap_sync_base_dn, config->base_dn,
                                      talloc_array_length(config->base_dn) - 1, false);
 
        /*
         *      If the connection is freed, all the sync state is also freed
         */
        talloc_set_destructor(sync, sync_state_free);
 
        return sync;
}
 
/** Add a new cookie packet ctx to the pending list
 *
 * Does not actually send the packet.
 *
 * @param[in] sync      the cookie was received for.
 * @param[in] refresh   the sync after storing this cookie.
 * @return
 *      - 0 on success.
 *      - -1 on failure
 */
int ldap_sync_cookie_store(sync_state_t *sync, bool refresh)
{
        sync_packet_ctx_t               *sync_packet_ctx = NULL;
        uint8_t                         *cookie = sync->cookie;
 
        MEM(sync_packet_ctx = talloc_zero(sync, sync_packet_ctx_t));
        sync_packet_ctx->sync = sync;
 
        sync_packet_ctx->type = SYNC_PACKET_TYPE_COOKIE;
        if (cookie) sync_packet_ctx->cookie = talloc_memdup(sync_packet_ctx, cookie, talloc_array_length(cookie));
        sync_packet_ctx->refresh = refresh;
 
        if (fr_dlist_insert_tail(&sync->pending, sync_packet_ctx) < 0) {
                talloc_free(sync_packet_ctx);
                return -1;
        }
        sync->pending_cookies++;
 
        return 0;
}
 
/** Event to handle storing of cookies on a timed basis
 *
 * Looks at the head of the list of pending sync packets for a cookie.
 * A cookie at the head says that all the previous changes have been
 * completed, so the cookie can be sent.
 */
void ldap_sync_cookie_event(fr_event_list_t *el, UNUSED fr_time_t now, void *uctx)
{
        sync_state_t            *sync = talloc_get_type_abort(uctx, sync_state_t);
        sync_packet_ctx_t       *sync_packet_ctx;
 
        if (sync->pending_cookies == 0) goto finish;
 
        /*
         *      Check the head entry in the list - is it a pending cookie
         */
        sync_packet_ctx = fr_dlist_head(&sync->pending);
        if ((sync_packet_ctx->type != SYNC_PACKET_TYPE_COOKIE) ||
            (sync_packet_ctx->status != SYNC_PACKET_PENDING)) goto finish;
 
        ldap_sync_cookie_send(sync_packet_ctx);
 
finish:
        (void) fr_event_timer_in(sync, el, &sync->cookie_ev, sync->inst->cookie_interval, ldap_sync_cookie_event, sync);
}
 
/** Enqueue a new cookie store packet
 *
 * Create a new internal packet containing the cookie we received from the LDAP server.
 * This allows the administrator to store the cookie and provide it on a future call to
 * load Cookie.
 *
 * @param[in] sync_packet_ctx   packet context containing the cookie to store.
 * @return
 *      - 0 on success.
 *      - -1 on failure.
*/
int ldap_sync_cookie_send(sync_packet_ctx_t *sync_packet_ctx)
{
        sync_state_t                    *sync = sync_packet_ctx->sync;
        proto_ldap_sync_ldap_thread_t   *thread = talloc_get_type_abort(sync->config->user_ctx, proto_ldap_sync_ldap_thread_t);
        fr_dbuff_t                      *dbuff;
        fr_pair_list_t                  pairs;
        fr_pair_t                       *vp;
        TALLOC_CTX                      *local = NULL;
        uint8_t                         *cookie = sync_packet_ctx->cookie;
 
        if (sync_packet_ctx->status != SYNC_PACKET_PENDING) return 0;
        sync_packet_ctx->status = SYNC_PACKET_PREPARING;
 
        FR_DBUFF_TALLOC_THREAD_LOCAL(&dbuff, 1024, 4096);
 
        local = talloc_new(NULL);
        fr_pair_list_init(&pairs);
        if (fr_pair_list_copy(local, &pairs, &sync->config->sync_pairs) < 0) {
        error:
                talloc_free(local);
                return -1;
        }
 
        fr_pair_list_append_by_da(local, vp, &pairs, attr_packet_type, (uint32_t)FR_LDAP_SYNC_CODE_COOKIE_STORE, true);
        if (!vp) goto error;
 
        fr_pair_list_append_by_da(local, vp, &pairs, attr_ldap_sync_packet_id, (uint32_t)sync->sync_no, true);
        if (!vp) goto error;
 
        /*
         *      Add the cookie to the packet, if set.
         *      If the server has indicated a refresh is required it can do so
         *      with no cookie set - so we store a blank cookie to clear anything
         *      which was previously stored.
         */
        if (cookie) {
                fr_pair_list_append_by_da_parent_len(local, vp, &pairs, attr_ldap_sync_cookie,
                                                     cookie, talloc_array_length(cookie), true);
                if (!vp) goto error;
        }
 
        if (fr_internal_encode_list(dbuff, &pairs, &encode_ctx) < 0) goto error;
        talloc_free(local);
 
        if (fr_network_listen_send_packet(thread->nr, thread->li, thread->li, fr_dbuff_buff(dbuff),
                                          fr_dbuff_used(dbuff), fr_time(), sync_packet_ctx) < 0) {
                sync_packet_ctx->status = SYNC_PACKET_PENDING;
                return -1;
        }
 
        sync_packet_ctx->status = SYNC_PACKET_PROCESSING;
 
        return 0;
}
 
/** Send a change packet to the workers
 *
 * Called each time a change packet is received and also from a
 * timer event retrying packets which previously failed to send.
 *
 * @param sync_packet_ctx Packet to send
 * @return
 *      - 0 on success.
 *      - -1 on failure.
 */
static int ldap_sync_entry_send_network(sync_packet_ctx_t *sync_packet_ctx)
{
        proto_ldap_sync_ldap_thread_t   *thread = talloc_get_type_abort(sync_packet_ctx->sync->config->user_ctx,
                                                                        proto_ldap_sync_ldap_thread_t);
        fr_dbuff_t                      *dbuff;
 
        FR_DBUFF_TALLOC_THREAD_LOCAL(&dbuff, 1024, 4096);
 
        if (fr_internal_encode_list(dbuff, &sync_packet_ctx->pairs, &encode_ctx) < 0) return -1;
        if (fr_network_listen_send_packet(thread->nr, thread->li, thread->li, fr_dbuff_buff(dbuff),
                                          fr_dbuff_used(dbuff), fr_time(), sync_packet_ctx) < 0) return -1;
 
        sync_packet_ctx->status = SYNC_PACKET_PROCESSING;
        fr_pair_list_free(&sync_packet_ctx->pairs);
 
        return 0;
}
 
/** Event to handle sending of any change packets which failed to send.
 *
 * Looks at the head of the list of pending sync packets for unsent
 * change packets and sends any up to the first cookie.
 */
static void ldap_sync_retry_event(fr_event_list_t *el, UNUSED fr_time_t now, void *uctx)
{
        sync_state_t            *sync = talloc_get_type_abort(uctx, sync_state_t);
        sync_packet_ctx_t       *sync_packet_ctx = NULL;
 
        while ((sync_packet_ctx = fr_dlist_next(&sync->pending, sync_packet_ctx))) {
                if (sync_packet_ctx->type != SYNC_PACKET_TYPE_CHANGE) break;
                if (sync_packet_ctx->status != SYNC_PACKET_PENDING) continue;
 
                /*
                 *      Retry sending packet.  Don't try any more if it fails.
                 */
                if (ldap_sync_entry_send_network(sync_packet_ctx) < 0) break;
        }
 
        /*
         *      We didn't run through the whole list, so there may be other pending
         *      packets - reschedule a retry event.
         */
        if (sync_packet_ctx) {
                (void) fr_event_timer_in(sync, el, &sync->retry_ev, sync->inst->retry_interval,
                                         ldap_sync_retry_event, sync);
        }
}
 
static fr_ldap_sync_packet_code_t const sync_packet_code_table[4] = {
        FR_LDAP_SYNC_CODE_PRESENT,
        FR_LDAP_SYNC_CODE_ADD,
        FR_LDAP_SYNC_CODE_MODIFY,
        FR_LDAP_SYNC_CODE_DELETE
};
 
/** Enqueue a new entry change packet.
 *
 * @param[in] sync      notification has arrived for.
 * @param[in] uuid      of the entry (RFC 4533 only).
 * @param[in] orig_dn   original DN of the entry - provided by those directories
 *                      implementing persistent search, when an entry is renamed.
 * @param[in] msg       containing the entry.
 * @param[in] op        The type of modification we need to perform to our
 *                      representation of the entry.
 * @return
 *      - 0 on success.
 *      - -1 on failure.
 */
int ldap_sync_entry_send(sync_state_t *sync, uint8_t const uuid[SYNC_UUID_LENGTH], struct berval *orig_dn,
                        LDAPMessage *msg, sync_op_t op)
{
        fr_ldap_sync_packet_code_t      pcode;
        fr_pair_list_t                  *pairs;
        fr_pair_t                       *vp;
        sync_packet_ctx_t               *sync_packet_ctx = NULL;
 
        MEM(sync_packet_ctx = talloc_zero(sync, sync_packet_ctx_t));
        sync_packet_ctx->sync = sync;
 
        fr_pair_list_init(&sync_packet_ctx->pairs);
        pairs = &sync_packet_ctx->pairs;
 
        if (fr_pair_list_copy(sync_packet_ctx, pairs, &sync->config->sync_pairs) < 0) {
        error:
                if (msg) ldap_msgfree(msg);
                talloc_free(sync_packet_ctx);
                return -1;
        }
 
        pcode = sync_packet_code_table[op];
 
        fr_pair_list_append_by_da(sync_packet_ctx, vp, pairs, attr_packet_type, (uint32_t)pcode, false);
        if (!vp) goto error;
 
        fr_pair_list_append_by_da(sync_packet_ctx, vp, pairs, attr_ldap_sync_packet_id, (uint32_t)sync->sync_no, false);
        if (!vp) goto error;
 
        /*
         *      Add the UUID if provided
         */
        if (uuid) {
                fr_pair_list_append_by_da_parent_len(sync_packet_ctx, vp, pairs, attr_ldap_sync_entry_uuid,
                                                     uuid, SYNC_UUID_LENGTH, true);
                if (!vp) goto error;
        }
 
        /*
         *      Add the original DN if provided
         */
        if (orig_dn && (orig_dn->bv_len > 0)) {
                fr_pair_list_append_by_da_parent_len(sync_packet_ctx, vp, pairs, attr_ldap_sync_orig_dn,
                                                     orig_dn->bv_val, orig_dn->bv_len, true);
                if (!vp) goto error;
        }
 
        /*
         *      Add the entry DN if there is an LDAP message to read
         */
        if (msg) {
                char                    *entry_dn = ldap_get_dn(sync->conn->handle, msg);
                map_t const             *map = NULL;
                struct berval           **values;
                int                     count, i;
 
                fr_pair_list_append_by_da_parent_len(sync_packet_ctx, vp, pairs, attr_ldap_sync_entry_dn,
                                                     entry_dn, strlen(entry_dn), true);
                if (!vp) goto error;
 
                ldap_memfree(entry_dn);
 
                /*
                 *  Map LDAP returned attributes to pairs as per update map
                 */
                while ((map = map_list_next(&sync->config->entry_map, map))) {
                        values = ldap_get_values_len(fr_ldap_handle_thread_local(), msg, map->rhs->name);
                        if (!values) goto next;
 
                        count = ldap_count_values_len(values);
 
                        for (i = 0; i < count; i++) {
                                if (values[i]->bv_len == 0) continue;
 
                                if (pair_append_by_tmpl_parent(sync_packet_ctx, &vp, pairs, map->lhs, true) < 0) break;
                                if (fr_value_box_from_str(vp, &vp->data, vp->vp_type, NULL, values[i]->bv_val,
                                                          values[i]->bv_len, NULL, true) < 0) {
                                        fr_pair_remove(pairs, vp);
                                        talloc_free(vp);
                                }
 
                                /*  Only += operator adds multiple values */
                                if (map->op != T_OP_ADD_EQ) break;
                        }
                next:
                        ldap_value_free_len(values);
                }
        }
 
        if (fr_dlist_insert_tail(&sync->pending, sync_packet_ctx) < 0) goto error;
 
        ldap_msgfree(msg);
 
        /*
         *      Send the packet and if it fails to send add a retry event
         */
        if ((ldap_sync_entry_send_network(sync_packet_ctx) < 0) &&
            (fr_event_timer_in(sync, sync->conn->conn->el, &sync->retry_ev,
                               sync->inst->retry_interval, ldap_sync_retry_event, sync) < 0)) {
                PERROR("Inserting LDAP sync retry timer failed");
        }
 
        return 0;
}
 
static void _proto_ldap_socket_init(fr_connection_t *conn, UNUSED fr_connection_state_t prev,
                                    UNUSED fr_connection_state_t state, void *uctx);
 
static void _proto_ldap_socket_open_connected(fr_connection_t *conn, UNUSED fr_connection_state_t prev,
                                              UNUSED fr_connection_state_t state, void *uctx);
 
/** Attempt to (re)initialise a connection
 *
 * Performs complete re-initialization of a connection.  Called during socket_open
 * to create the initial connection and again any time we need to reopen the connection.
 *
 * @param[in] el        the event list managing listen event.
 * @param[in] now       current time.
 * @param[in] user_ctx  Listener.
 */
static void proto_ldap_connection_init(UNUSED fr_event_list_t *el, UNUSED fr_time_t now, void *user_ctx)
{
        fr_listen_t                     *listen = talloc_get_type_abort(user_ctx, fr_listen_t);
        proto_ldap_sync_ldap_thread_t   *thread = talloc_get_type_abort(listen->thread_instance, proto_ldap_sync_ldap_thread_t);
        proto_ldap_sync_ldap_t const    *inst = talloc_get_type_abort_const(thread->inst, proto_ldap_sync_ldap_t);
 
        if (thread->conn) talloc_free(thread->conn);
 
        /*
         *      Allocate an outbound LDAP connection
         */
        thread->conn = fr_ldap_connection_state_alloc(thread, thread->el, &inst->handle_config, "ldap_sync");
 
        if (!thread->conn) {
                PERROR("Failed (re)initialising connection, will retry in %pV seconds",
                       fr_box_time_delta(inst->handle_config.reconnection_delay));
 
                if (fr_event_timer_in(thread, thread->el, &thread->conn_retry_ev,
                                      inst->handle_config.reconnection_delay,
                                      proto_ldap_connection_init, listen) < 0) {
                        FATAL("Failed inserting event: %s", fr_strerror());
                }
        }
 
        /*
         *      Add watch functions on the LDAP connection
         */
        fr_connection_add_watch_post(thread->conn, FR_CONNECTION_STATE_INIT,
                                     _proto_ldap_socket_init, true, thread);
 
        fr_connection_add_watch_post(thread->conn, FR_CONNECTION_STATE_CONNECTED,
                                     _proto_ldap_socket_open_connected, true, thread);
 
        /*
         *      Signal the connection to start
         */
        fr_connection_signal_init(thread->conn);
 
        return;
}
 
/** Child listener mod_close
 *
 * Ensures the LDAP connection is signalled to close gracefully when
 * the listener is closed.
 */
static int proto_ldap_child_mod_close(fr_listen_t *li)
{
        proto_ldap_sync_ldap_thread_t   *thread = talloc_get_type_abort(li->thread_instance, proto_ldap_sync_ldap_thread_t);
 
        fr_connection_signal_shutdown(thread->conn);
        return 0;
}
 
/** LDAP sync mod_read for child listener
 *
 * Called when there is data to read on the LDAP connection
 *
 * Actual packets are created by the various callbacks since a single LDAP
 * message can result in multiple packets to process e.g.:
 *
 *   - Sync Info Message with syncInfoValue of syncIdSet can reference
 *     multiple directory entries.
 *   - Various sync related messages can include a new cookie in
 *     addition to their other data.
 */
static ssize_t proto_ldap_child_mod_read(fr_listen_t *li, UNUSED void **packet_ctx, UNUSED fr_time_t *recv_time_p, UNUSED uint8_t *buffer,
                                         UNUSED size_t buffer_len, UNUSED size_t *leftover)
{
        proto_ldap_sync_ldap_thread_t   *thread = talloc_get_type_abort(li->thread_instance, proto_ldap_sync_ldap_thread_t);
        fr_ldap_connection_t            *conn = talloc_get_type_abort(thread->conn->h, fr_ldap_connection_t);
        struct  timeval                 poll = { 1, 0 };
        LDAPMessage                     *msg = NULL;
        int                             ret = 0;
        fr_ldap_rcode_t                 rcode;
        sync_state_t                    *sync = NULL;
        fr_rb_tree_t                    *tree;
        int                             type, msgid;
        LDAPControl                     **ctrls = NULL;
        sync_msg_t                      callback = NULL;
 
        fr_assert(conn);
 
        /*
         *      If there are already too many outstanding requests just return.
         *      This will (potentially) cause the TCP buffer to fill and push the
         *      backpressure back to the LDAP server.
         */
        if (fr_network_listen_outstanding(thread->nr, li) >= thread->inst->max_outstanding) return 0;
 
        tree = talloc_get_type_abort(conn->uctx, fr_rb_tree_t);
 
        /*
         *      Pull the next outstanding message from this connection.
         *      We process one message at a time so that the message can be
         *      passed to the worker, and freed once the request has been
         *      handled.
         */
        ret = ldap_result(conn->handle, LDAP_RES_ANY, LDAP_MSG_ONE, &poll, &msg);
 
        switch (ret) {
        case 0: /*
                 *      Timeout - this has been observed if changes are being
                 *      processed slowly, the TCP receive buffer fills and
                 *      the LDAP directory pauses sending data for a period.
                 *      Then all pending changes are processed and the receive buffer
                 *      is emptied.
                 *      The situation resolves when the directory starts sending
                 *      data again.
                 */
                return 0;
 
        case -1:
                rcode = fr_ldap_error_check(NULL, conn, NULL, NULL);
                if (rcode == LDAP_PROC_BAD_CONN) return -2;
                return -1;
 
        default:
                break;
        }
 
        /*
         *      De-multiplex based on msgid
         */
        if (!msg) return 0;
 
        msgid = ldap_msgid(msg);
        type = ldap_msgtype(msg);
 
        ret = 0;
        if (msgid == 0) {
                WARN("Ignoring unsolicited %s message",
                     fr_table_str_by_value(sync_ldap_msg_table, type, "<invalid>"));
        free_msg:
                if (ctrls) ldap_controls_free(ctrls);
                ldap_msgfree(msg);
                return ret;
        }
 
        sync = fr_rb_find(tree, &(sync_state_t){.msgid = msgid});
        if (!sync) {
                WARN("Ignoring msgid %i, doesn't match any outstanding syncs", msgid);
                goto free_msg;
        }
 
        /*
         *      Check for errors contained within the message.
         *      This has to be per message, as multiple syncs
         *      are multiplexed together on one connection.
         */
        switch (fr_ldap_error_check(&ctrls, conn, msg, sync->config->base_dn)) {
        case LDAP_PROC_SUCCESS:
                break;
 
        /*
         *      The e-syncRefresRequired result code is the server informing us that
         *      the query needs to be restarted for a new refresh phase to run.
         *      It is sent as the result code for a SearchResultsDone message.
         */
        case LDAP_PROC_REFRESH_REQUIRED:
                if (type != LDAP_RES_SEARCH_RESULT) {
                        PERROR("e-syncRefreshRequired result code received on wrong message type");
                        ret = -1;
                        goto free_msg;
                }
 
                DEBUG2("LDAP Server returned e-syncRefreshRequired");
                if (sync->config->refresh) {
                        return sync->config->refresh(sync, msg, ctrls);
                }
                goto free_msg;
 
        /*
         *      Don't think this should happen... but libldap
         *      is wonky sometimes...
         */
        case LDAP_PROC_BAD_CONN:
                PERROR("Connection unusable");
                ret = -2;
                goto free_msg;
 
        default:
        sync_error:
                PERROR("Sync error");
                ret = -1;
                goto free_msg;
        }
 
        DEBUG3("Got %s message for sync (msgid %i)",
               fr_table_str_by_value(sync_ldap_msg_table, type, "<invalid>"), sync->msgid);
 
        switch (type) {
        case LDAP_RES_SEARCH_REFERENCE:
        case LDAP_RES_SEARCH_ENTRY:
                callback = sync->config->entry;
                break;
 
        case LDAP_RES_INTERMEDIATE:
                callback = sync->config->intermediate;
                break;
 
        default:
                WARN("Ignoring unexpected message type (%i)", type);
                ret = 0;
                goto free_msg;
        }
 
        if (callback) {
                ret = callback(sync, msg, ctrls);
        } else {
        /*
         *      Callbacks are responsible for freeing the msg
         *      so if there is no callback, free it.
         */
                ldap_msgfree(msg);
        }
        if (ret < 0) goto sync_error;
 
        ldap_controls_free(ctrls);
 
        return 0;
}
 
/** Send a fake packet to run the "load Cookie" section
 *
 * @param ctx           Context to allocate temporary pairs in.
 * @param inst          LDAP sync configuration.
 * @param sync_no       Id of the sync whose.
 * @param thread        Thread specific LDAP sync data.
 * @return
 *      - 0 on success
 *      - -1 on failure
 */
static int proto_ldap_cookie_load_send(TALLOC_CTX *ctx, proto_ldap_sync_ldap_t const *inst, size_t sync_no,
                                       proto_ldap_sync_ldap_thread_t *thread) {
        size_t                  j, len;
        sync_config_t           *config = inst->parent->sync_config[sync_no];
        fr_pair_list_t          pairs;
        fr_pair_t               *vp;
        fr_dbuff_t              *dbuff;
        fr_ldap_connection_t    *ldap_conn = thread->conn->h;
 
        fr_pair_list_init(&pairs);
        if (unlikely(fr_pair_list_copy(ctx, &pairs, &config->sync_pairs) < 0)) return -1;
 
        /*
         *      Ensure we have access to the thread instance
         *      in for the demux callbacks
         */
        inst->parent->sync_config[sync_no]->user_ctx = thread;
 
        /*
         *      Assess the namingContext which applies to this sync
         */
        for (j = 0; j < talloc_array_length(ldap_conn->directory->naming_contexts); j++) {
                len = strlen(ldap_conn->directory->naming_contexts[j]);
                if (strlen(config->base_dn) < len) continue;
 
                if (strncasecmp(&config->base_dn[strlen(config->base_dn)-len],
                                ldap_conn->directory->naming_contexts[j],
                                strlen(ldap_conn->directory->naming_contexts[j])) == 0) {
                        config->root_dn = ldap_conn->directory->naming_contexts[j];
                        break;
                }
        }
 
        /*
         *      Set up callbacks based on directory type.
         */
        switch (ldap_conn->directory->sync_type) {
        case FR_LDAP_SYNC_RFC4533:
                config->init = rfc4533_sync_init;
                config->entry = rfc4533_sync_search_entry;
                config->intermediate = rfc4533_sync_intermediate;
                config->refresh = rfc4533_sync_refresh_required;
                break;
 
        case FR_LDAP_SYNC_PERSISTENT_SEARCH:
                config->init = persistent_sync_state_init;
                config->entry = persistent_sync_search_entry;
                break;
 
        case FR_LDAP_SYNC_ACTIVE_DIRECTORY:
                config->init = active_directory_sync_state_init;
                config->entry = active_directory_sync_search_entry;
                break;
 
        default:
                fr_assert(0);
        }
 
        fr_pair_list_append_by_da(ctx, vp, &pairs, attr_packet_type,
                                  (uint32_t)FR_LDAP_SYNC_CODE_COOKIE_LOAD, false);
        if (!vp) return -1;
        fr_pair_list_append_by_da(ctx, vp, &pairs, attr_ldap_sync_packet_id, (uint32_t)sync_no, false);
        if (!vp) return -1;
 
        if (config->root_dn) {
                fr_pair_list_append_by_da_parent_len(ctx, vp, &pairs, attr_ldap_sync_root_dn,
                                                     config->root_dn, strlen(config->root_dn), false);
                if (!vp) return -1;
        }
 
        FR_DBUFF_TALLOC_THREAD_LOCAL(&dbuff, 1024, 4096);
 
        if (fr_internal_encode_list(dbuff, &pairs, &encode_ctx) < 0) return -1;
 
        if (fr_network_listen_send_packet(thread->nr, thread->li, thread->li,
                                          fr_dbuff_buff(dbuff), fr_dbuff_used(dbuff),
                                          fr_time(), NULL) < 0) return -1;
        fr_pair_list_free(&pairs);
        return 0;
}
 
/** Timer event to retry running "load Cookie" on failures
 *
 */
static void proto_ldap_cookie_load_retry(fr_event_list_t *el, UNUSED fr_time_t now, void *uctx) {
        proto_ldap_cookie_load_retry_ctx  *retry_ctx = talloc_get_type_abort(uctx, proto_ldap_cookie_load_retry_ctx);
 
        DEBUG2("Retrying \"load Cookie\" for sync no %ld", retry_ctx->sync_no);
        if (proto_ldap_cookie_load_send(retry_ctx, retry_ctx->inst, retry_ctx->sync_no,
                                        retry_ctx->thread) < 0) {
                ERROR("Failed retrying \"load Cookie\".  Will try again in %pV seconds",
                      fr_box_time_delta(retry_ctx->inst->handle_config.reconnection_delay));
                (void) fr_event_timer_in(retry_ctx->thread->conn->h, el,
                                         &retry_ctx->inst->parent->sync_config[retry_ctx->sync_no]->ev,
                                         retry_ctx->inst->handle_config.reconnection_delay,
                                         proto_ldap_cookie_load_retry, retry_ctx);
                return;
        }
        talloc_free(retry_ctx);
}
 
/** LDAP sync mod_write for child listener
 *
 * Handle any returned data after the worker has processed the packet and,
 * for packets where tracking structures were used, ensure they are freed.
 */
static ssize_t proto_ldap_child_mod_write(fr_listen_t *li, void *packet_ctx, UNUSED fr_time_t request_time,
                                          uint8_t *buffer, size_t buffer_len, UNUSED size_t written)
{
        proto_ldap_sync_ldap_thread_t   *thread = talloc_get_type_abort(li->thread_instance, proto_ldap_sync_ldap_thread_t);
        proto_ldap_sync_ldap_t const    *inst = talloc_get_type_abort_const(thread->inst, proto_ldap_sync_ldap_t);
        fr_dbuff_t                      dbuff;
        fr_ldap_sync_packet_code_t      pcode;
        uint32_t                        packet_id;
        fr_pair_list_t                  tmp;
        fr_pair_t                       *vp = NULL;
        ssize_t                         ret;
        TALLOC_CTX                      *local;
        sync_packet_ctx_t               *sync_packet_ctx = NULL;
 
        local = talloc_new(NULL);
        fr_dbuff_init(&dbuff, buffer, buffer_len);
 
        if (packet_ctx) sync_packet_ctx = talloc_get_type_abort(packet_ctx, sync_packet_ctx_t);
 
        /*
         *      Extract returned attributes into a temporary list
         */
        fr_pair_list_init(&tmp);
 
        ret = fr_internal_decode_list_dbuff(local, &tmp, fr_dict_root(dict_ldap_sync), &dbuff, NULL);
        if (ret < 0) goto finish;
 
        /*
         *      There should always be a packet ID and code
         */
        vp = fr_pair_find_by_da(&tmp, NULL, attr_ldap_sync_packet_id);
        fr_assert(vp);
        packet_id = vp->vp_uint32;
 
        vp = fr_pair_find_by_da(&tmp, NULL, attr_packet_type);
        fr_assert(vp);
        pcode = vp->vp_uint32;
 
        switch (pcode) {
        case FR_LDAP_SYNC_CODE_COOKIE_LOAD_RESPONSE:
        {
                uint8_t *cookie = NULL;
 
                /*
                 *      If the received packet ID is greater than the number of syncs
                 *      we have then something very bad has happened
                 */
                fr_assert (packet_id <= talloc_array_length(inst->parent->sync_config));
 
                /*
                 *      Look for the returned cookie.
                 */
                vp = fr_pair_find_by_da_nested(&tmp, NULL, attr_ldap_sync_cookie);
                if (vp) cookie = talloc_memdup(inst, vp->vp_octets, vp->vp_length);
 
                if (inst->parent->sync_config[packet_id]->init(thread->conn->h, packet_id, inst->parent, cookie) < 0) {
                        ret = -1;
                        goto finish;
                }
        }
                break;
 
        case FR_LDAP_SYNC_CODE_ENTRY_RESPONSE:
                break;
 
        case FR_LDAP_SYNC_CODE_COOKIE_STORE_RESPONSE:
        {
                sync_config_t const     *sync_config;
 
                if (!sync_packet_ctx || !sync_packet_ctx->refresh) break;
 
                /*
                 *      Abandon the old sync and start a new one with the relevant cookie.
                 */
                sync_config = sync_packet_ctx->sync->config;
                DEBUG3("Restarting sync with base %s", sync_config->base_dn);
                talloc_free(sync_packet_ctx->sync);
                if (inst->parent->sync_config[packet_id]->init(thread->conn->h, packet_id, inst->parent,
                                                                  sync_packet_ctx->cookie) < 0) {
                        ret = -1;
                        goto finish;
                }
        }
                break;
 
        case FR_LDAP_SYNC_CODE_COOKIE_LOAD_FAIL:
        {
                proto_ldap_cookie_load_retry_ctx *retry_ctx;
 
                ERROR("Load Cookie failed for sync %d, retrying in %pV seconds", packet_id,
                      fr_box_time_delta(inst->handle_config.reconnection_delay));
 
                MEM(retry_ctx = talloc(thread, proto_ldap_cookie_load_retry_ctx));
                *retry_ctx = (proto_ldap_cookie_load_retry_ctx){
                        .thread = thread,
                        .inst = inst,
                        .sync_no = packet_id,
                };
 
                (void) fr_event_timer_in(thread->conn->h, thread->el, &inst->parent->sync_config[packet_id]->ev,
                                         inst->handle_config.reconnection_delay,
                                         proto_ldap_cookie_load_retry, retry_ctx);
        }
                break;
 
        default:
                ERROR("Invalid packet type returned %d", pcode);
                break;
        }
 
        if (sync_packet_ctx) {
                sync_state_t            *sync = sync_packet_ctx->sync;
                sync_packet_ctx_t       *pc;
                proto_ldap_sync_t       *ldap_sync = inst->parent;
 
                sync_packet_ctx->status = SYNC_PACKET_COMPLETE;
 
                /*
                 *      A cookie has been stored, reset the counter of changes
                 */
                if (sync_packet_ctx->type == SYNC_PACKET_TYPE_COOKIE) sync->changes_since_cookie = 0;
 
                /*
                 *      Pop any processed updates from the head of the list
                 */
                while ((pc = fr_dlist_head(&sync->pending))) {
                        /*
                         *      If the head entry in the list is a pending cookie but we have
                         *      not processed enough entries and there are more pending
                         *      cookies, mark this one as processed.
                         */
                        if ((pc->type == SYNC_PACKET_TYPE_COOKIE) && (pc->status == SYNC_PACKET_PENDING) &&
                            (sync->changes_since_cookie < ldap_sync->cookie_changes) &&
                             (sync->pending_cookies > 1)) pc->status = SYNC_PACKET_COMPLETE;
 
                        if (pc->status != SYNC_PACKET_COMPLETE) break;
 
                        /*
                         *      Update counters depending on entry type
                         */
                        if (pc->type == SYNC_PACKET_TYPE_COOKIE) {
                                sync->pending_cookies--;
                        } else {
                                sync->changes_since_cookie++;
                        }
                        pc = fr_dlist_pop_head(&sync->pending);
                        talloc_free(pc);
                }
 
                /*
                 *      If the head of the list is a cookie which has not yet
                 *      been processed and sufficient changes have been recorded
                 *      send the cookie.
                 */
                if (pc && (pc->type == SYNC_PACKET_TYPE_COOKIE) && (pc->status == SYNC_PACKET_PENDING) &&
                    (sync->changes_since_cookie >= ldap_sync->cookie_changes)) ldap_sync_cookie_send(pc);
        }
 
finish:
        fr_pair_list_free(&tmp);
        talloc_free(local);
 
        return ret;
}
 
/** Callback for socket errors when running initial root query
 */
static void _proto_ldap_socket_open_error(UNUSED fr_event_list_t *el, UNUSED int fd, UNUSED int flags,
                                          UNUSED int fd_errno, void *uctx)
{
        proto_ldap_dir_ctx      *dir_ctx = talloc_get_type_abort(uctx, proto_ldap_dir_ctx);
        fr_ldap_connection_t    *ldap_conn = talloc_get_type_abort(dir_ctx->conn->h, fr_ldap_connection_t);
 
        talloc_free(dir_ctx);
        fr_ldap_state_error(ldap_conn);
}
 
/** Callback to process results of initial root query, identifying directory type
 */
static void _proto_ldap_socket_open_read(fr_event_list_t *el, int fd, UNUSED int flags, void *uctx)
{
        proto_ldap_dir_ctx              *dir_ctx = talloc_get_type_abort(uctx, proto_ldap_dir_ctx);
        fr_ldap_connection_t            *ldap_conn = talloc_get_type_abort(dir_ctx->conn->h, fr_ldap_connection_t);
        proto_ldap_sync_ldap_t const    *inst = talloc_get_type_abort_const(dir_ctx->main_listen->app_io_instance,
                                                                            proto_ldap_sync_ldap_t);
        proto_ldap_sync_ldap_thread_t   *thread = talloc_get_type_abort(dir_ctx->main_listen->thread_instance,
                                                                        proto_ldap_sync_ldap_thread_t);
        fr_ldap_rcode_t                 status;
        LDAPMessage                     *result;
 
        size_t                          i;
        TALLOC_CTX                      *local = NULL;
 
        /*
         *      Fetch the result.  Setting the timeout to 0 here means use
         *      res_timeout from the configuration.
         */
        status = fr_ldap_result(&result, NULL, ldap_conn, dir_ctx->msgid, LDAP_MSG_ALL, NULL, fr_time_delta_from_msec(0));
        if (status != LDAP_PROC_SUCCESS) {
                PERROR("Failed querying for directory type");
                if (result) ldap_msgfree(result);
        error:
                talloc_free(dir_ctx);
                if (local) talloc_free(local);
                fr_connection_signal_reconnect(ldap_conn->conn, FR_CONNECTION_FAILED);
                return;
        }
 
        fr_ldap_directory_result_parse(ldap_conn->directory, ldap_conn->handle, result, ldap_conn->config->name);
        ldap_msgfree(result);
 
        /*
         *      If the server does not support any of the relevant controls, we just
         *      tidy up - no point in signalling to reconnect.
         */
        if (ldap_conn->directory->sync_type == FR_LDAP_SYNC_NONE) {
                ERROR("LDAP sync configured for directory which does not support any suitable control");
                talloc_free(dir_ctx);
                fr_connection_signal_halt(ldap_conn->conn);
                return;
        }
 
        /*
         *      We've done all the preparation work on the LDAP connection, now
         *      use normal network event listeners.
         */
        fr_event_fd_delete(el, fd, FR_EVENT_FILTER_IO);
        fr_network_listen_add(thread->nr, thread->li);
 
        DEBUG2("Starting sync(s)");
 
        local = talloc_new(NULL);
 
        /*
         *      Sync operations start by sending a fake packet to run
         *      the load Cookie section in order to retrieve the cookie
         */
        for (i = 0; i < talloc_array_length(inst->parent->sync_config); i++) {
                if (proto_ldap_cookie_load_send(local, inst, i, thread) < 0) goto error;
        }
 
        talloc_free(dir_ctx);
        talloc_free(local);
}
 
/** Allocate a child listener
 *
 * Called as a watch function when the LDAP connection enters the INIT state
 */
static void _proto_ldap_socket_init(fr_connection_t *conn, UNUSED fr_connection_state_t prev,
                                    UNUSED fr_connection_state_t state, void *uctx)
{
        proto_ldap_sync_ldap_thread_t   *thread = talloc_get_type_abort(uctx, proto_ldap_sync_ldap_thread_t);
        fr_listen_t                     *li;
 
        MEM(li = talloc_zero(conn, fr_listen_t));
 
        thread->li = li;
        li->thread_instance = thread;
 
        li->app_io = &proto_ldap_sync_child;
        li->name = li->app_io->common.name;
        li->default_message_size = li->app_io->default_message_size;
 
        /*
         *      Use the app from the parent listener to access
         *      the encoder / decoder functions
         */
        li->app = thread->parent->app;
        li->app_instance = thread->parent->app_instance;
        li->server_cs = thread->inst->parent->server_cs;
}
 
/** Callback for closure of LDAP connection
 *
 * Schedules re-start of the connection if appropriate
 */
static void _proto_ldap_socket_closed(UNUSED fr_connection_t *conn, fr_connection_state_t prev,
                                      UNUSED fr_connection_state_t state, void *uctx)
{
        fr_listen_t                     *listen = talloc_get_type_abort(uctx, fr_listen_t);
        proto_ldap_sync_ldap_thread_t   *thread = talloc_get_type_abort(listen->thread_instance, proto_ldap_sync_ldap_thread_t);
        proto_ldap_sync_ldap_t const    *inst = thread->inst;
 
        if (fr_event_loop_exiting(thread->el)) return;
 
        if (prev == FR_CONNECTION_STATE_CONNECTED) {
                ERROR("LDAP connection closed.  Scheduling restart in %pVs",
                       fr_box_time_delta(inst->handle_config.reconnection_delay));
                if (fr_event_timer_in(thread, thread->el, &thread->conn_retry_ev,
                                      inst->handle_config.reconnection_delay,
                                      proto_ldap_connection_init, listen) < 0) {
                        FATAL("Failed inserting event: %s", fr_strerror());
                }
        }
}
 
/** Query an LDAP server to establish its type
 *
 * Called as a watch function once the LDAP connection enters the CONNECTED state
 *
 * There are three different forms of LDAP sync/persistent search - so we need
 * to know what we're dealing with, and whether the relevant options have been enabled.
 */
static void _proto_ldap_socket_open_connected(fr_connection_t *conn, UNUSED fr_connection_state_t prev,
                                              UNUSED fr_connection_state_t state, void *uctx)
{
        proto_ldap_sync_ldap_thread_t   *thread = talloc_get_type_abort(uctx, proto_ldap_sync_ldap_thread_t);
        fr_listen_t                     *listen = talloc_get_type_abort(thread->parent, fr_listen_t);
        proto_ldap_sync_ldap_t const    *inst = talloc_get_type_abort_const(thread->inst,
                                                                            proto_ldap_sync_ldap_t);
        fr_ldap_connection_t            *ldap_conn = talloc_get_type_abort(conn->h, fr_ldap_connection_t);
 
        proto_ldap_dir_ctx              *dir_ctx;
 
        if (ldap_conn->fd < 0) {
        connection_failed:
                if (fr_event_timer_in(thread, thread->el, &thread->conn_retry_ev,
                                      inst->handle_config.reconnection_delay,
                                      proto_ldap_connection_init, listen) < 0) {
                        FATAL("Failed inserting event: %s", fr_strerror());
                }
                return;
        }
 
        thread->li->fd = ldap_conn->fd;
 
        MEM(dir_ctx = talloc_zero(inst, proto_ldap_dir_ctx));
        if (!dir_ctx) goto connection_failed;
 
        dir_ctx->main_listen = listen;
        dir_ctx->conn = conn;
        dir_ctx->child_listen = thread->li;
 
#ifdef SO_RCVBUF
        if (inst->recv_buff_is_set) {
                int opt;
 
                opt = inst->recv_buff;
                if (setsockopt(ldap_conn->fd, SOL_SOCKET, SO_RCVBUF, &opt, sizeof(int)) < 0) {
                        WARN("Failed setting 'recv_buff': %s", fr_syserror(errno));
                }
        }
#endif
 
        /*
         *      Set the callback which will handle the results of this query
         */
        if (fr_event_fd_insert(conn, NULL, conn->el, ldap_conn->fd,
                               _proto_ldap_socket_open_read,
                               NULL,
                               _proto_ldap_socket_open_error,
                               dir_ctx) < 0) {
                                        goto connection_failed;
        }
 
        /*
         *      Allocate the directory structure and send the query
         */
        dir_ctx->msgid = fr_ldap_conn_directory_alloc_async(ldap_conn);
 
        if (dir_ctx->msgid < 0) {
                talloc_free(dir_ctx);
                goto connection_failed;
        }
 
        /*
         *      Add a watch to catch closed LDAP connections
         */
        fr_connection_add_watch_post(thread->conn, FR_CONNECTION_STATE_CLOSED,
                                     _proto_ldap_socket_closed, true, listen);
}
 
/** Callback triggered when parent listener app_io has its event list set
 *
 * Initiates the actual outbound LDAP connection
 *
 * @param[in] li        The parent listener.
 * @param[in] el        Event list for this listener.
 * @param[in] nr        Network handler.
 */
static void mod_event_list_set(fr_listen_t *li, fr_event_list_t *el, void *nr)
{
        proto_ldap_sync_ldap_t const    *inst = talloc_get_type_abort_const(li->app_io_instance, proto_ldap_sync_ldap_t);
        proto_ldap_sync_ldap_thread_t   *thread = talloc_get_type_abort(li->thread_instance, proto_ldap_sync_ldap_thread_t);
 
        /*
         *      Set up thread data
         */
        thread->name = inst->handle_config.name;
        thread->parent = li;
        thread->el = el;
        thread->nr = nr;
        thread->inst = inst;
 
        /*
         *      Initialise the connection
         */
        proto_ldap_connection_init(el, fr_event_list_time(el), li);
}
 
static int mod_instantiate(module_inst_ctx_t const *mctx)
{
        proto_ldap_sync_ldap_t  *inst = talloc_get_type_abort(mctx->inst->data, proto_ldap_sync_ldap_t);
        CONF_SECTION            *conf = mctx->inst->conf;
        char const              *server;
 
        /*
         *      Verify that the LDAP server configuration is valid, either
         *      distinct server and port or an LDAP url.
         */
        fr_assert(inst->server);
 
        server = inst->server;
        inst->handle_config.server = talloc_strdup(inst, "");
 
        if (ldap_is_ldap_url(server)) {
                if (fr_ldap_server_url_check(&inst->handle_config, server, conf) < 0) return -1;
        } else {
                if (fr_ldap_server_config_check(&inst->handle_config, server, conf) < 0) return -1;
        }
 
        inst->handle_config.server[talloc_array_length(inst->handle_config.server) - 1] = '\0';
 
        inst->handle_config.name = talloc_typed_asprintf(inst, "proto_ldap_conn (%s)",
                                                         cf_section_name(cf_item_to_section(cf_parent(cf_parent(conf)))));
 
        return 0;
}
 
static int mod_bootstrap(module_inst_ctx_t const *mctx)
{
        proto_ldap_sync_ldap_t  *inst = talloc_get_type_abort(mctx->inst->data, proto_ldap_sync_ldap_t);
        CONF_SECTION            *conf = mctx->inst->conf;
        dl_module_inst_t const  *dl_inst;
 
        dl_inst = dl_module_instance_by_data(inst);
        fr_assert(dl_inst);
 
        inst->parent = talloc_get_type_abort(dl_inst->parent->data, proto_ldap_sync_t);
        inst->cs = conf;
 
        if (inst->recv_buff_is_set) {
                FR_INTEGER_BOUND_CHECK("recv_buff", inst->recv_buff, >=, 32);
                FR_INTEGER_BOUND_CHECK("recv_buff", inst->recv_buff, <=, INT_MAX);
        }
 
        return 0;
}
 
fr_app_io_t proto_ldap_sync_child = {
        .common = {
                .magic                  = MODULE_MAGIC_INIT,
                .name                   = "ldap_sync_child"
        },
        .read                   = proto_ldap_child_mod_read,
        .write                  = proto_ldap_child_mod_write,
        .close                  = proto_ldap_child_mod_close,
 
        .default_message_size   = 4096,
        .track_duplicates       = false,
};
 
fr_app_io_t proto_ldap_sync_ldap = {
        .common = {
                .magic                  = MODULE_MAGIC_INIT,
                .name                   = "ldap_sync_ldap",
                .config                 = proto_ldap_sync_ldap_config,
                .inst_size              = sizeof(proto_ldap_sync_ldap_t),
                .thread_inst_size       = sizeof(proto_ldap_sync_ldap_thread_t),
 
                .bootstrap              = mod_bootstrap,
                .instantiate            = mod_instantiate
        },
 
        .default_message_size   = 4096,
        .track_duplicates       = false,
 
        .event_list_set         = mod_event_list_set,
};