doc-xml/smbdotconf: fix server [min|max] protocol documentation

[Samba/gebeck_regimport.git] / source4 / wrepl_server / wrepl_out_helpers.c

/* 
   Unix SMB/CIFS implementation.
   
   WINS Replication server
   
   Copyright (C) Stefan Metzmacher      2005
   
   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 3 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, see <http://www.gnu.org/licenses/>.
*/

#include "includes.h"
#include "lib/events/events.h"
#include "lib/socket/socket.h"
#include "smbd/service_task.h"
#include "smbd/service_stream.h"
#include "librpc/gen_ndr/winsrepl.h"
#include "wrepl_server/wrepl_server.h"
#include "nbt_server/wins/winsdb.h"
#include "libcli/composite/composite.h"
#include "libcli/wrepl/winsrepl.h"
#include "libcli/resolve/resolve.h"
#include "param/param.h"

enum wreplsrv_out_connect_stage {
        WREPLSRV_OUT_CONNECT_STAGE_WAIT_SOCKET,
        WREPLSRV_OUT_CONNECT_STAGE_WAIT_ASSOC_CTX,
        WREPLSRV_OUT_CONNECT_STAGE_DONE
};

struct wreplsrv_out_connect_state {
        enum wreplsrv_out_connect_stage stage;
        struct composite_context *c;
        struct wrepl_associate assoc_io;
        enum winsrepl_partner_type type;
        struct wreplsrv_out_connection *wreplconn;
        struct tevent_req *subreq;
};

static void wreplsrv_out_connect_handler_treq(struct tevent_req *subreq);

static NTSTATUS wreplsrv_out_connect_wait_socket(struct wreplsrv_out_connect_state *state)
{
        NTSTATUS status;

        status = wrepl_connect_recv(state->subreq);
        TALLOC_FREE(state->subreq);
        NT_STATUS_NOT_OK_RETURN(status);

        state->subreq = wrepl_associate_send(state,
                                             state->wreplconn->service->task->event_ctx,
                                             state->wreplconn->sock, &state->assoc_io);
        NT_STATUS_HAVE_NO_MEMORY(state->subreq);

        tevent_req_set_callback(state->subreq,
                                wreplsrv_out_connect_handler_treq,
                                state);

        state->stage = WREPLSRV_OUT_CONNECT_STAGE_WAIT_ASSOC_CTX;

        return NT_STATUS_OK;
}

static NTSTATUS wreplsrv_out_connect_wait_assoc_ctx(struct wreplsrv_out_connect_state *state)
{
        NTSTATUS status;

        status = wrepl_associate_recv(state->subreq, &state->assoc_io);
        TALLOC_FREE(state->subreq);
        NT_STATUS_NOT_OK_RETURN(status);

        state->wreplconn->assoc_ctx.peer_ctx = state->assoc_io.out.assoc_ctx;
        state->wreplconn->assoc_ctx.peer_major = state->assoc_io.out.major_version;

        if (state->type == WINSREPL_PARTNER_PUSH) {
                if (state->wreplconn->assoc_ctx.peer_major >= 5) {
                        state->wreplconn->partner->push.wreplconn = state->wreplconn;
                        talloc_steal(state->wreplconn->partner, state->wreplconn);
                } else {
                        state->type = WINSREPL_PARTNER_NONE;
                }
        } else if (state->type == WINSREPL_PARTNER_PULL) {
                state->wreplconn->partner->pull.wreplconn = state->wreplconn;
                talloc_steal(state->wreplconn->partner, state->wreplconn);
        }

        state->stage = WREPLSRV_OUT_CONNECT_STAGE_DONE;

        return NT_STATUS_OK;
}

static void wreplsrv_out_connect_handler(struct wreplsrv_out_connect_state *state)
{
        struct composite_context *c = state->c;

        switch (state->stage) {
        case WREPLSRV_OUT_CONNECT_STAGE_WAIT_SOCKET:
                c->status = wreplsrv_out_connect_wait_socket(state);
                break;
        case WREPLSRV_OUT_CONNECT_STAGE_WAIT_ASSOC_CTX:
                c->status = wreplsrv_out_connect_wait_assoc_ctx(state);
                c->state  = COMPOSITE_STATE_DONE;
                break;
        case WREPLSRV_OUT_CONNECT_STAGE_DONE:
                c->status = NT_STATUS_INTERNAL_ERROR;
        }

        if (!NT_STATUS_IS_OK(c->status)) {
                c->state = COMPOSITE_STATE_ERROR;
        }

        if (c->state >= COMPOSITE_STATE_DONE && c->async.fn) {
                c->async.fn(c);
        }
}

static void wreplsrv_out_connect_handler_treq(struct tevent_req *subreq)
{
        struct wreplsrv_out_connect_state *state = tevent_req_callback_data(subreq,
                                                   struct wreplsrv_out_connect_state);
        wreplsrv_out_connect_handler(state);
        return;
}

static struct composite_context *wreplsrv_out_connect_send(struct wreplsrv_partner *partner,
                                                           enum winsrepl_partner_type type,
                                                           struct wreplsrv_out_connection *wreplconn)
{
        struct composite_context *c = NULL;
        struct wreplsrv_service *service = partner->service;
        struct wreplsrv_out_connect_state *state = NULL;
        struct wreplsrv_out_connection **wreplconnp = &wreplconn;
        bool cached_connection = false;

        c = talloc_zero(partner, struct composite_context);
        if (!c) goto failed;

        state = talloc_zero(c, struct wreplsrv_out_connect_state);
        if (!state) goto failed;
        state->c        = c;
        state->type     = type;

        c->state        = COMPOSITE_STATE_IN_PROGRESS;
        c->event_ctx    = service->task->event_ctx;
        c->private_data = state;

        if (type == WINSREPL_PARTNER_PUSH) {
                cached_connection       = true;
                wreplconn               = partner->push.wreplconn;
                wreplconnp              = &partner->push.wreplconn;
        } else if (type == WINSREPL_PARTNER_PULL) {
                cached_connection       = true;
                wreplconn               = partner->pull.wreplconn;
                wreplconnp              = &partner->pull.wreplconn;
        }

        /* we have a connection already, so use it */
        if (wreplconn) {
                if (wrepl_socket_is_connected(wreplconn->sock)) {
                        state->stage    = WREPLSRV_OUT_CONNECT_STAGE_DONE;
                        state->wreplconn= wreplconn;
                        composite_done(c);
                        return c;
                } else if (!cached_connection) {
                        state->stage    = WREPLSRV_OUT_CONNECT_STAGE_DONE;
                        state->wreplconn= NULL;
                        composite_done(c);
                        return c;
                } else {
                        talloc_free(wreplconn);
                        *wreplconnp = NULL;
                }
        }

        wreplconn = talloc_zero(state, struct wreplsrv_out_connection);
        if (!wreplconn) goto failed;

        wreplconn->service      = service;
        wreplconn->partner      = partner;
        wreplconn->sock         = wrepl_socket_init(wreplconn, service->task->event_ctx);
        if (!wreplconn->sock) goto failed;

        state->stage    = WREPLSRV_OUT_CONNECT_STAGE_WAIT_SOCKET;
        state->wreplconn= wreplconn;
        state->subreq   = wrepl_connect_send(state,
                                             service->task->event_ctx,
                                             wreplconn->sock,
                                             partner->our_address?partner->our_address:wrepl_best_ip(service->task->lp_ctx, partner->address),
                                             partner->address);
        if (!state->subreq) goto failed;

        tevent_req_set_callback(state->subreq,
                                wreplsrv_out_connect_handler_treq,
                                state);

        return c;
failed:
        talloc_free(c);
        return NULL;
}

static NTSTATUS wreplsrv_out_connect_recv(struct composite_context *c, TALLOC_CTX *mem_ctx,
                                          struct wreplsrv_out_connection **wreplconn)
{
        NTSTATUS status;

        status = composite_wait(c);

        if (NT_STATUS_IS_OK(status)) {
                struct wreplsrv_out_connect_state *state = talloc_get_type(c->private_data,
                                                           struct wreplsrv_out_connect_state);
                if (state->wreplconn) {
                        *wreplconn = talloc_reference(mem_ctx, state->wreplconn);
                        if (!*wreplconn) status = NT_STATUS_NO_MEMORY;
                } else {
                        status = NT_STATUS_CONNECTION_DISCONNECTED;
                }
        }

        talloc_free(c);
        return status;
        
}

struct wreplsrv_pull_table_io {
        struct {
                struct wreplsrv_partner *partner;
                uint32_t num_owners;
                struct wrepl_wins_owner *owners;
        } in;
        struct {
                uint32_t num_owners;
                struct wrepl_wins_owner *owners;
        } out;
};

enum wreplsrv_pull_table_stage {
        WREPLSRV_PULL_TABLE_STAGE_WAIT_CONNECTION,
        WREPLSRV_PULL_TABLE_STAGE_WAIT_TABLE_REPLY,
        WREPLSRV_PULL_TABLE_STAGE_DONE
};

struct wreplsrv_pull_table_state {
        enum wreplsrv_pull_table_stage stage;
        struct composite_context *c;
        struct wrepl_pull_table table_io;
        struct wreplsrv_pull_table_io *io;
        struct composite_context *creq;
        struct wreplsrv_out_connection *wreplconn;
        struct tevent_req *subreq;
};

static void wreplsrv_pull_table_handler_treq(struct tevent_req *subreq);

static NTSTATUS wreplsrv_pull_table_wait_connection(struct wreplsrv_pull_table_state *state)
{
        NTSTATUS status;

        status = wreplsrv_out_connect_recv(state->creq, state, &state->wreplconn);
        NT_STATUS_NOT_OK_RETURN(status);

        state->table_io.in.assoc_ctx = state->wreplconn->assoc_ctx.peer_ctx;
        state->subreq = wrepl_pull_table_send(state,
                                              state->wreplconn->service->task->event_ctx,
                                              state->wreplconn->sock, &state->table_io);
        NT_STATUS_HAVE_NO_MEMORY(state->subreq);

        tevent_req_set_callback(state->subreq,
                                wreplsrv_pull_table_handler_treq,
                                state);

        state->stage = WREPLSRV_PULL_TABLE_STAGE_WAIT_TABLE_REPLY;

        return NT_STATUS_OK;
}

static NTSTATUS wreplsrv_pull_table_wait_table_reply(struct wreplsrv_pull_table_state *state)
{
        NTSTATUS status;

        status = wrepl_pull_table_recv(state->subreq, state, &state->table_io);
        TALLOC_FREE(state->subreq);
        NT_STATUS_NOT_OK_RETURN(status);

        state->stage = WREPLSRV_PULL_TABLE_STAGE_DONE;

        return NT_STATUS_OK;
}

static void wreplsrv_pull_table_handler(struct wreplsrv_pull_table_state *state)
{
        struct composite_context *c = state->c;

        switch (state->stage) {
        case WREPLSRV_PULL_TABLE_STAGE_WAIT_CONNECTION:
                c->status = wreplsrv_pull_table_wait_connection(state);
                break;
        case WREPLSRV_PULL_TABLE_STAGE_WAIT_TABLE_REPLY:
                c->status = wreplsrv_pull_table_wait_table_reply(state);
                c->state  = COMPOSITE_STATE_DONE;
                break;
        case WREPLSRV_PULL_TABLE_STAGE_DONE:
                c->status = NT_STATUS_INTERNAL_ERROR;
        }

        if (!NT_STATUS_IS_OK(c->status)) {
                c->state = COMPOSITE_STATE_ERROR;
        }

        if (c->state >= COMPOSITE_STATE_DONE && c->async.fn) {
                c->async.fn(c);
        }
}

static void wreplsrv_pull_table_handler_creq(struct composite_context *creq)
{
        struct wreplsrv_pull_table_state *state = talloc_get_type(creq->async.private_data,
                                                  struct wreplsrv_pull_table_state);
        wreplsrv_pull_table_handler(state);
        return;
}

static void wreplsrv_pull_table_handler_treq(struct tevent_req *subreq)
{
        struct wreplsrv_pull_table_state *state = tevent_req_callback_data(subreq,
                                                  struct wreplsrv_pull_table_state);
        wreplsrv_pull_table_handler(state);
        return;
}

static struct composite_context *wreplsrv_pull_table_send(TALLOC_CTX *mem_ctx, struct wreplsrv_pull_table_io *io)
{
        struct composite_context *c = NULL;
        struct wreplsrv_service *service = io->in.partner->service;
        struct wreplsrv_pull_table_state *state = NULL;

        c = talloc_zero(mem_ctx, struct composite_context);
        if (!c) goto failed;

        state = talloc_zero(c, struct wreplsrv_pull_table_state);
        if (!state) goto failed;
        state->c        = c;
        state->io       = io;

        c->state        = COMPOSITE_STATE_IN_PROGRESS;
        c->event_ctx    = service->task->event_ctx;
        c->private_data = state;

        if (io->in.num_owners) {
                state->table_io.out.num_partners        = io->in.num_owners;
                state->table_io.out.partners            = io->in.owners;
                state->stage                            = WREPLSRV_PULL_TABLE_STAGE_DONE;
                composite_done(c);
                return c;
        }

        state->stage    = WREPLSRV_PULL_TABLE_STAGE_WAIT_CONNECTION;
        state->creq     = wreplsrv_out_connect_send(io->in.partner, WINSREPL_PARTNER_PULL, NULL);
        if (!state->creq) goto failed;

        state->creq->async.fn           = wreplsrv_pull_table_handler_creq;
        state->creq->async.private_data = state;

        return c;
failed:
        talloc_free(c);
        return NULL;
}

static NTSTATUS wreplsrv_pull_table_recv(struct composite_context *c, TALLOC_CTX *mem_ctx,
                                         struct wreplsrv_pull_table_io *io)
{
        NTSTATUS status;

        status = composite_wait(c);

        if (NT_STATUS_IS_OK(status)) {
                struct wreplsrv_pull_table_state *state = talloc_get_type(c->private_data,
                                                          struct wreplsrv_pull_table_state);
                io->out.num_owners      = state->table_io.out.num_partners;
                io->out.owners          = talloc_reference(mem_ctx, state->table_io.out.partners);
        }

        talloc_free(c);
        return status;  
}

struct wreplsrv_pull_names_io {
        struct {
                struct wreplsrv_partner *partner;
                struct wreplsrv_out_connection *wreplconn;
                struct wrepl_wins_owner owner;
        } in;
        struct {
                uint32_t num_names;
                struct wrepl_name *names;
        } out;
};

enum wreplsrv_pull_names_stage {
        WREPLSRV_PULL_NAMES_STAGE_WAIT_CONNECTION,
        WREPLSRV_PULL_NAMES_STAGE_WAIT_SEND_REPLY,
        WREPLSRV_PULL_NAMES_STAGE_DONE
};

struct wreplsrv_pull_names_state {
        enum wreplsrv_pull_names_stage stage;
        struct composite_context *c;
        struct wrepl_pull_names pull_io;
        struct wreplsrv_pull_names_io *io;
        struct composite_context *creq;
        struct wreplsrv_out_connection *wreplconn;
        struct tevent_req *subreq;
};

static void wreplsrv_pull_names_handler_treq(struct tevent_req *subreq);

static NTSTATUS wreplsrv_pull_names_wait_connection(struct wreplsrv_pull_names_state *state)
{
        NTSTATUS status;

        status = wreplsrv_out_connect_recv(state->creq, state, &state->wreplconn);
        NT_STATUS_NOT_OK_RETURN(status);

        state->pull_io.in.assoc_ctx     = state->wreplconn->assoc_ctx.peer_ctx;
        state->pull_io.in.partner       = state->io->in.owner;
        state->subreq = wrepl_pull_names_send(state,
                                              state->wreplconn->service->task->event_ctx,
                                              state->wreplconn->sock,
                                              &state->pull_io);
        NT_STATUS_HAVE_NO_MEMORY(state->subreq);

        tevent_req_set_callback(state->subreq,
                                wreplsrv_pull_names_handler_treq,
                                state);

        state->stage = WREPLSRV_PULL_NAMES_STAGE_WAIT_SEND_REPLY;

        return NT_STATUS_OK;
}

static NTSTATUS wreplsrv_pull_names_wait_send_reply(struct wreplsrv_pull_names_state *state)
{
        NTSTATUS status;

        status = wrepl_pull_names_recv(state->subreq, state, &state->pull_io);
        TALLOC_FREE(state->subreq);
        NT_STATUS_NOT_OK_RETURN(status);

        state->stage = WREPLSRV_PULL_NAMES_STAGE_DONE;

        return NT_STATUS_OK;
}

static void wreplsrv_pull_names_handler(struct wreplsrv_pull_names_state *state)
{
        struct composite_context *c = state->c;

        switch (state->stage) {
        case WREPLSRV_PULL_NAMES_STAGE_WAIT_CONNECTION:
                c->status = wreplsrv_pull_names_wait_connection(state);
                break;
        case WREPLSRV_PULL_NAMES_STAGE_WAIT_SEND_REPLY:
                c->status = wreplsrv_pull_names_wait_send_reply(state);
                c->state  = COMPOSITE_STATE_DONE;
                break;
        case WREPLSRV_PULL_NAMES_STAGE_DONE:
                c->status = NT_STATUS_INTERNAL_ERROR;
        }

        if (!NT_STATUS_IS_OK(c->status)) {
                c->state = COMPOSITE_STATE_ERROR;
        }

        if (c->state >= COMPOSITE_STATE_DONE && c->async.fn) {
                c->async.fn(c);
        }
}

static void wreplsrv_pull_names_handler_creq(struct composite_context *creq)
{
        struct wreplsrv_pull_names_state *state = talloc_get_type(creq->async.private_data,
                                                  struct wreplsrv_pull_names_state);
        wreplsrv_pull_names_handler(state);
        return;
}

static void wreplsrv_pull_names_handler_treq(struct tevent_req *subreq)
{
        struct wreplsrv_pull_names_state *state = tevent_req_callback_data(subreq,
                                                  struct wreplsrv_pull_names_state);
        wreplsrv_pull_names_handler(state);
        return;
}

static struct composite_context *wreplsrv_pull_names_send(TALLOC_CTX *mem_ctx, struct wreplsrv_pull_names_io *io)
{
        struct composite_context *c = NULL;
        struct wreplsrv_service *service = io->in.partner->service;
        struct wreplsrv_pull_names_state *state = NULL;
        enum winsrepl_partner_type partner_type = WINSREPL_PARTNER_PULL;

        if (io->in.wreplconn) partner_type = WINSREPL_PARTNER_NONE;

        c = talloc_zero(mem_ctx, struct composite_context);
        if (!c) goto failed;

        state = talloc_zero(c, struct wreplsrv_pull_names_state);
        if (!state) goto failed;
        state->c        = c;
        state->io       = io;

        c->state        = COMPOSITE_STATE_IN_PROGRESS;
        c->event_ctx    = service->task->event_ctx;
        c->private_data = state;

        state->stage    = WREPLSRV_PULL_NAMES_STAGE_WAIT_CONNECTION;
        state->creq     = wreplsrv_out_connect_send(io->in.partner, partner_type, io->in.wreplconn);
        if (!state->creq) goto failed;

        state->creq->async.fn           = wreplsrv_pull_names_handler_creq;
        state->creq->async.private_data = state;

        return c;
failed:
        talloc_free(c);
        return NULL;
}

static NTSTATUS wreplsrv_pull_names_recv(struct composite_context *c, TALLOC_CTX *mem_ctx,
                                         struct wreplsrv_pull_names_io *io)
{
        NTSTATUS status;

        status = composite_wait(c);

        if (NT_STATUS_IS_OK(status)) {
                struct wreplsrv_pull_names_state *state = talloc_get_type(c->private_data,
                                                          struct wreplsrv_pull_names_state);
                io->out.num_names       = state->pull_io.out.num_names;
                io->out.names           = talloc_reference(mem_ctx, state->pull_io.out.names);
        }

        talloc_free(c);
        return status;
        
}

enum wreplsrv_pull_cycle_stage {
        WREPLSRV_PULL_CYCLE_STAGE_WAIT_TABLE_REPLY,
        WREPLSRV_PULL_CYCLE_STAGE_WAIT_SEND_REPLIES,
        WREPLSRV_PULL_CYCLE_STAGE_WAIT_STOP_ASSOC,
        WREPLSRV_PULL_CYCLE_STAGE_DONE
};

struct wreplsrv_pull_cycle_state {
        enum wreplsrv_pull_cycle_stage stage;
        struct composite_context *c;
        struct wreplsrv_pull_cycle_io *io;
        struct wreplsrv_pull_table_io table_io;
        uint32_t current;
        struct wreplsrv_pull_names_io names_io;
        struct composite_context *creq;
        struct wrepl_associate_stop assoc_stop_io;
        struct tevent_req *subreq;
};

static void wreplsrv_pull_cycle_handler_creq(struct composite_context *creq);
static void wreplsrv_pull_cycle_handler_treq(struct tevent_req *subreq);

static NTSTATUS wreplsrv_pull_cycle_next_owner_do_work(struct wreplsrv_pull_cycle_state *state)
{
        struct wreplsrv_owner *current_owner=NULL;
        struct wreplsrv_owner *local_owner;
        uint32_t i;
        uint64_t old_max_version = 0;
        bool do_pull = false;

        for (i=state->current; i < state->table_io.out.num_owners; i++) {
                current_owner = wreplsrv_find_owner(state->io->in.partner->service,
                                                    state->io->in.partner->pull.table,
                                                    state->table_io.out.owners[i].address);

                local_owner = wreplsrv_find_owner(state->io->in.partner->service,
                                                  state->io->in.partner->service->table,
                                                  state->table_io.out.owners[i].address);
                /*
                 * this means we are ourself the current owner,
                 * and we don't want replicate ourself
                 */
                if (!current_owner) continue;

                /*
                 * this means we don't have any records of this owner
                 * so fetch them
                 */
                if (!local_owner) {
                        do_pull         = true;
                        
                        break;
                }

                /*
                 * this means the remote partner has some new records of this owner
                 * fetch them
                 */
                if (current_owner->owner.max_version > local_owner->owner.max_version) {
                        do_pull         = true;
                        old_max_version = local_owner->owner.max_version;
                        break;
                }
        }
        state->current = i;

        if (do_pull) {
                state->names_io.in.partner              = state->io->in.partner;
                state->names_io.in.wreplconn            = state->io->in.wreplconn;
                state->names_io.in.owner                = current_owner->owner;
                state->names_io.in.owner.min_version    = old_max_version + 1;
                state->creq = wreplsrv_pull_names_send(state, &state->names_io);
                NT_STATUS_HAVE_NO_MEMORY(state->creq);

                state->creq->async.fn           = wreplsrv_pull_cycle_handler_creq;
                state->creq->async.private_data = state;

                return STATUS_MORE_ENTRIES;
        }

        return NT_STATUS_OK;
}

static NTSTATUS wreplsrv_pull_cycle_next_owner_wrapper(struct wreplsrv_pull_cycle_state *state)
{
        NTSTATUS status;

        status = wreplsrv_pull_cycle_next_owner_do_work(state);
        if (NT_STATUS_IS_OK(status)) {
                state->stage = WREPLSRV_PULL_CYCLE_STAGE_DONE;
        } else if (NT_STATUS_EQUAL(STATUS_MORE_ENTRIES, status)) {
                state->stage = WREPLSRV_PULL_CYCLE_STAGE_WAIT_SEND_REPLIES;
                status = NT_STATUS_OK;
        }

        if (state->stage == WREPLSRV_PULL_CYCLE_STAGE_DONE && state->io->in.wreplconn) {
                state->assoc_stop_io.in.assoc_ctx       = state->io->in.wreplconn->assoc_ctx.peer_ctx;
                state->assoc_stop_io.in.reason          = 0;
                state->subreq = wrepl_associate_stop_send(state,
                                                          state->io->in.wreplconn->service->task->event_ctx,
                                                          state->io->in.wreplconn->sock,
                                                          &state->assoc_stop_io);
                NT_STATUS_HAVE_NO_MEMORY(state->subreq);

                tevent_req_set_callback(state->subreq,
                                        wreplsrv_pull_cycle_handler_treq,
                                        state);

                state->stage = WREPLSRV_PULL_CYCLE_STAGE_WAIT_STOP_ASSOC;
        }

        return status;
}

static NTSTATUS wreplsrv_pull_cycle_wait_table_reply(struct wreplsrv_pull_cycle_state *state)
{
        NTSTATUS status;
        uint32_t i;

        status = wreplsrv_pull_table_recv(state->creq, state, &state->table_io);
        NT_STATUS_NOT_OK_RETURN(status);

        /* update partner table */
        for (i=0; i < state->table_io.out.num_owners; i++) {
                status = wreplsrv_add_table(state->io->in.partner->service,
                                            state->io->in.partner, 
                                            &state->io->in.partner->pull.table,
                                            state->table_io.out.owners[i].address,
                                            state->table_io.out.owners[i].max_version);
                NT_STATUS_NOT_OK_RETURN(status);
        }

        status = wreplsrv_pull_cycle_next_owner_wrapper(state);
        NT_STATUS_NOT_OK_RETURN(status);

        return status;
}

static NTSTATUS wreplsrv_pull_cycle_apply_records(struct wreplsrv_pull_cycle_state *state)
{
        NTSTATUS status;

        status = wreplsrv_apply_records(state->io->in.partner,
                                        &state->names_io.in.owner,
                                        state->names_io.out.num_names,
                                        state->names_io.out.names);
        NT_STATUS_NOT_OK_RETURN(status);

        talloc_free(state->names_io.out.names);
        ZERO_STRUCT(state->names_io);

        return NT_STATUS_OK;
}

static NTSTATUS wreplsrv_pull_cycle_wait_send_replies(struct wreplsrv_pull_cycle_state *state)
{
        NTSTATUS status;

        status = wreplsrv_pull_names_recv(state->creq, state, &state->names_io);
        NT_STATUS_NOT_OK_RETURN(status);

        /*
         * TODO: this should maybe an async call,
         *       because we may need some network access
         *       for conflict resolving
         */
        status = wreplsrv_pull_cycle_apply_records(state);
        NT_STATUS_NOT_OK_RETURN(status);

        status = wreplsrv_pull_cycle_next_owner_wrapper(state);
        NT_STATUS_NOT_OK_RETURN(status);

        return status;
}

static NTSTATUS wreplsrv_pull_cycle_wait_stop_assoc(struct wreplsrv_pull_cycle_state *state)
{
        NTSTATUS status;

        status = wrepl_associate_stop_recv(state->subreq, &state->assoc_stop_io);
        TALLOC_FREE(state->subreq);
        NT_STATUS_NOT_OK_RETURN(status);

        state->stage = WREPLSRV_PULL_CYCLE_STAGE_DONE;

        return status;
}

static void wreplsrv_pull_cycle_handler(struct wreplsrv_pull_cycle_state *state)
{
        struct composite_context *c = state->c;

        switch (state->stage) {
        case WREPLSRV_PULL_CYCLE_STAGE_WAIT_TABLE_REPLY:
                c->status = wreplsrv_pull_cycle_wait_table_reply(state);
                break;
        case WREPLSRV_PULL_CYCLE_STAGE_WAIT_SEND_REPLIES:
                c->status = wreplsrv_pull_cycle_wait_send_replies(state);
                break;
        case WREPLSRV_PULL_CYCLE_STAGE_WAIT_STOP_ASSOC:
                c->status = wreplsrv_pull_cycle_wait_stop_assoc(state);
                break;
        case WREPLSRV_PULL_CYCLE_STAGE_DONE:
                c->status = NT_STATUS_INTERNAL_ERROR;
        }

        if (state->stage == WREPLSRV_PULL_CYCLE_STAGE_DONE) {
                c->state  = COMPOSITE_STATE_DONE;
        }

        if (!NT_STATUS_IS_OK(c->status)) {
                c->state = COMPOSITE_STATE_ERROR;
        }

        if (c->state >= COMPOSITE_STATE_DONE && c->async.fn) {
                c->async.fn(c);
        }
}

static void wreplsrv_pull_cycle_handler_creq(struct composite_context *creq)
{
        struct wreplsrv_pull_cycle_state *state = talloc_get_type(creq->async.private_data,
                                                  struct wreplsrv_pull_cycle_state);
        wreplsrv_pull_cycle_handler(state);
        return;
}

static void wreplsrv_pull_cycle_handler_treq(struct tevent_req *subreq)
{
        struct wreplsrv_pull_cycle_state *state = tevent_req_callback_data(subreq,
                                                  struct wreplsrv_pull_cycle_state);
        wreplsrv_pull_cycle_handler(state);
        return;
}

struct composite_context *wreplsrv_pull_cycle_send(TALLOC_CTX *mem_ctx, struct wreplsrv_pull_cycle_io *io)
{
        struct composite_context *c = NULL;
        struct wreplsrv_service *service = io->in.partner->service;
        struct wreplsrv_pull_cycle_state *state = NULL;

        c = talloc_zero(mem_ctx, struct composite_context);
        if (!c) goto failed;

        state = talloc_zero(c, struct wreplsrv_pull_cycle_state);
        if (!state) goto failed;
        state->c        = c;
        state->io       = io;

        c->state        = COMPOSITE_STATE_IN_PROGRESS;
        c->event_ctx    = service->task->event_ctx;
        c->private_data = state;

        state->stage    = WREPLSRV_PULL_CYCLE_STAGE_WAIT_TABLE_REPLY;
        state->table_io.in.partner      = io->in.partner;
        state->table_io.in.num_owners   = io->in.num_owners;
        state->table_io.in.owners       = io->in.owners;
        state->creq = wreplsrv_pull_table_send(state, &state->table_io);
        if (!state->creq) goto failed;

        state->creq->async.fn           = wreplsrv_pull_cycle_handler_creq;
        state->creq->async.private_data = state;

        return c;
failed:
        talloc_free(c);
        return NULL;
}

NTSTATUS wreplsrv_pull_cycle_recv(struct composite_context *c)
{
        NTSTATUS status;

        status = composite_wait(c);

        talloc_free(c);
        return status;
}

enum wreplsrv_push_notify_stage {
        WREPLSRV_PUSH_NOTIFY_STAGE_WAIT_CONNECT,
        WREPLSRV_PUSH_NOTIFY_STAGE_WAIT_UPDATE,
        WREPLSRV_PUSH_NOTIFY_STAGE_WAIT_INFORM,
        WREPLSRV_PUSH_NOTIFY_STAGE_DONE
};

struct wreplsrv_push_notify_state {
        enum wreplsrv_push_notify_stage stage;
        struct composite_context *c;
        struct wreplsrv_push_notify_io *io;
        enum wrepl_replication_cmd command;
        bool full_table;
        struct wrepl_send_ctrl ctrl;
        struct wrepl_packet req_packet;
        struct wrepl_packet *rep_packet;
        struct composite_context *creq;
        struct wreplsrv_out_connection *wreplconn;
        struct tevent_req *subreq;
};

static void wreplsrv_push_notify_handler_creq(struct composite_context *creq);
static void wreplsrv_push_notify_handler_treq(struct tevent_req *subreq);

static NTSTATUS wreplsrv_push_notify_update(struct wreplsrv_push_notify_state *state)
{
        struct wreplsrv_service *service = state->io->in.partner->service;
        struct wrepl_packet *req = &state->req_packet;
        struct wrepl_replication *repl_out = &state->req_packet.message.replication;
        struct wrepl_table *table_out = &state->req_packet.message.replication.info.table;
        NTSTATUS status;

        /* prepare the outgoing request */
        req->opcode     = WREPL_OPCODE_BITS;
        req->assoc_ctx  = state->wreplconn->assoc_ctx.peer_ctx;
        req->mess_type  = WREPL_REPLICATION;

        repl_out->command = state->command;

        status = wreplsrv_fill_wrepl_table(service, state, table_out,
                                           service->wins_db->local_owner, state->full_table);
        NT_STATUS_NOT_OK_RETURN(status);

        /* queue the request */
        state->subreq = wrepl_request_send(state,
                                           state->wreplconn->service->task->event_ctx,
                                           state->wreplconn->sock, req, NULL);
        NT_STATUS_HAVE_NO_MEMORY(state->subreq);

        tevent_req_set_callback(state->subreq,
                                wreplsrv_push_notify_handler_treq,
                                state);

        state->stage = WREPLSRV_PUSH_NOTIFY_STAGE_WAIT_UPDATE;

        return NT_STATUS_OK;
}

static NTSTATUS wreplsrv_push_notify_inform(struct wreplsrv_push_notify_state *state)
{
        struct wreplsrv_service *service = state->io->in.partner->service;
        struct wrepl_packet *req = &state->req_packet;
        struct wrepl_replication *repl_out = &state->req_packet.message.replication;
        struct wrepl_table *table_out = &state->req_packet.message.replication.info.table;
        NTSTATUS status;

        req->opcode     = WREPL_OPCODE_BITS;
        req->assoc_ctx  = state->wreplconn->assoc_ctx.peer_ctx;
        req->mess_type  = WREPL_REPLICATION;

        repl_out->command = state->command;

        status = wreplsrv_fill_wrepl_table(service, state, table_out,
                                           service->wins_db->local_owner, state->full_table);
        NT_STATUS_NOT_OK_RETURN(status);

        /* we won't get a reply to a inform message */
        state->ctrl.send_only           = true;

        state->subreq = wrepl_request_send(state,
                                           state->wreplconn->service->task->event_ctx,
                                           state->wreplconn->sock, req, &state->ctrl);
        NT_STATUS_HAVE_NO_MEMORY(state->subreq);

        tevent_req_set_callback(state->subreq,
                                wreplsrv_push_notify_handler_treq,
                                state);

        state->stage = WREPLSRV_PUSH_NOTIFY_STAGE_WAIT_INFORM;

        return NT_STATUS_OK;
}

static NTSTATUS wreplsrv_push_notify_wait_connect(struct wreplsrv_push_notify_state *state)
{
        NTSTATUS status;

        status = wreplsrv_out_connect_recv(state->creq, state, &state->wreplconn);
        NT_STATUS_NOT_OK_RETURN(status);

        /* is the peer doesn't support inform fallback to update */
        switch (state->command) {
        case WREPL_REPL_INFORM:
                if (state->wreplconn->assoc_ctx.peer_major < 5) {
                        state->command = WREPL_REPL_UPDATE;
                }
                break;
        case WREPL_REPL_INFORM2:
                if (state->wreplconn->assoc_ctx.peer_major < 5) {
                        state->command = WREPL_REPL_UPDATE2;
                }
                break;
        default:
                break;
        }

        switch (state->command) {
        case WREPL_REPL_UPDATE:
                state->full_table = true;
                return wreplsrv_push_notify_update(state);
        case WREPL_REPL_UPDATE2:
                state->full_table = false;
                return wreplsrv_push_notify_update(state);
        case WREPL_REPL_INFORM:
                state->full_table = true;
                return wreplsrv_push_notify_inform(state);
        case WREPL_REPL_INFORM2:
                state->full_table = false;
                return wreplsrv_push_notify_inform(state);
        default:
                return NT_STATUS_INTERNAL_ERROR;
        }
}

static NTSTATUS wreplsrv_push_notify_wait_update(struct wreplsrv_push_notify_state *state)
{
        struct wreplsrv_in_connection *wrepl_in;
        struct tstream_context *stream;
        NTSTATUS status;

        status = wrepl_request_recv(state->subreq, state, NULL);
        TALLOC_FREE(state->subreq);
        NT_STATUS_NOT_OK_RETURN(status);

        /*
         * now we need to convert the wrepl_socket (client connection)
         * into a wreplsrv_in_connection (server connection), because
         * we'll act as a server on this connection after the WREPL_REPL_UPDATE*
         * message is received by the peer.
         */

        status = wrepl_socket_split_stream(state->wreplconn->sock, state, &stream);
        NT_STATUS_NOT_OK_RETURN(status);

        /*
         * now create a wreplsrv_in_connection,
         * on which we act as server
         *
         * NOTE: stream will be stolen by
         *       wreplsrv_in_connection_merge()
         */
        status = wreplsrv_in_connection_merge(state->io->in.partner,
                                              state->wreplconn->assoc_ctx.peer_ctx,
                                              &stream,
                                              &wrepl_in);
        NT_STATUS_NOT_OK_RETURN(status);

        /* now we can free the wreplsrv_out_connection */
        TALLOC_FREE(state->wreplconn);

        state->stage = WREPLSRV_PUSH_NOTIFY_STAGE_DONE;
        return NT_STATUS_OK;
}

static NTSTATUS wreplsrv_push_notify_wait_inform(struct wreplsrv_push_notify_state *state)
{
        NTSTATUS status;

        status = wrepl_request_recv(state->subreq, state, NULL);
        TALLOC_FREE(state->subreq);
        NT_STATUS_NOT_OK_RETURN(status);

        state->stage = WREPLSRV_PUSH_NOTIFY_STAGE_DONE;
        return status;
}

static void wreplsrv_push_notify_handler(struct wreplsrv_push_notify_state *state)
{
        struct composite_context *c = state->c;

        switch (state->stage) {
        case WREPLSRV_PUSH_NOTIFY_STAGE_WAIT_CONNECT:
                c->status = wreplsrv_push_notify_wait_connect(state);
                break;
        case WREPLSRV_PUSH_NOTIFY_STAGE_WAIT_UPDATE:
                c->status = wreplsrv_push_notify_wait_update(state);
                break;
        case WREPLSRV_PUSH_NOTIFY_STAGE_WAIT_INFORM:
                c->status = wreplsrv_push_notify_wait_inform(state);
                break;
        case WREPLSRV_PUSH_NOTIFY_STAGE_DONE:
                c->status = NT_STATUS_INTERNAL_ERROR;
        }

        if (state->stage == WREPLSRV_PUSH_NOTIFY_STAGE_DONE) {
                c->state  = COMPOSITE_STATE_DONE;
        }

        if (!NT_STATUS_IS_OK(c->status)) {
                c->state = COMPOSITE_STATE_ERROR;
        }

        if (c->state >= COMPOSITE_STATE_DONE && c->async.fn) {
                c->async.fn(c);
        }
}

static void wreplsrv_push_notify_handler_creq(struct composite_context *creq)
{
        struct wreplsrv_push_notify_state *state = talloc_get_type(creq->async.private_data,
                                                   struct wreplsrv_push_notify_state);
        wreplsrv_push_notify_handler(state);
        return;
}

static void wreplsrv_push_notify_handler_treq(struct tevent_req *subreq)
{
        struct wreplsrv_push_notify_state *state = tevent_req_callback_data(subreq,
                                                   struct wreplsrv_push_notify_state);
        wreplsrv_push_notify_handler(state);
        return;
}

struct composite_context *wreplsrv_push_notify_send(TALLOC_CTX *mem_ctx, struct wreplsrv_push_notify_io *io)
{
        struct composite_context *c = NULL;
        struct wreplsrv_service *service = io->in.partner->service;
        struct wreplsrv_push_notify_state *state = NULL;
        enum winsrepl_partner_type partner_type;

        c = talloc_zero(mem_ctx, struct composite_context);
        if (!c) goto failed;

        state = talloc_zero(c, struct wreplsrv_push_notify_state);
        if (!state) goto failed;
        state->c        = c;
        state->io       = io;

        if (io->in.inform) {
                /* we can cache the connection in partner->push->wreplconn */
                partner_type = WINSREPL_PARTNER_PUSH;
                if (io->in.propagate) {
                        state->command  = WREPL_REPL_INFORM2;
                } else {
                        state->command  = WREPL_REPL_INFORM;
                }
        } else {
                /* we can NOT cache the connection */
                partner_type = WINSREPL_PARTNER_NONE;
                if (io->in.propagate) {
                        state->command  = WREPL_REPL_UPDATE2;
                } else {
                        state->command  = WREPL_REPL_UPDATE;
                }       
        }

        c->state        = COMPOSITE_STATE_IN_PROGRESS;
        c->event_ctx    = service->task->event_ctx;
        c->private_data = state;

        state->stage    = WREPLSRV_PUSH_NOTIFY_STAGE_WAIT_CONNECT;
        state->creq     = wreplsrv_out_connect_send(io->in.partner, partner_type, NULL);
        if (!state->creq) goto failed;

        state->creq->async.fn           = wreplsrv_push_notify_handler_creq;
        state->creq->async.private_data = state;

        return c;
failed:
        talloc_free(c);
        return NULL;
}

NTSTATUS wreplsrv_push_notify_recv(struct composite_context *c)
{
        NTSTATUS status;

        status = composite_wait(c);

        talloc_free(c);
        return status;
}