/* 
   Unix SMB/Netbios implementation.
   Version 1.9.
   NBT netbios routines and daemon - version 2
   Copyright (C) Andrew Tridgell 1994-1997
   Copyright (C) Luke Kenneth Casson Leighton 1994-1997 
   Copyright (C) Jeremy Allison 1994-1997
   
   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., 675 Mass Ave, Cambridge, MA 02139, USA.
   
*/

#include "includes.h"
#include "smb.h"

extern int DEBUGLEVEL;
extern pstring scope;
extern struct in_addr ipzero;
extern pstring myname;

/* This is our local master browser list database. */
extern struct browse_cache_record *lmb_browserlist;

static struct work_record *call_work;
static struct subnet_record *call_subrec;

/*******************************************************************
  This is the NetServerEnum callback.
  ******************************************************************/

static void callback(char *sname, uint32 stype, char *comment)
{
  struct work_record *work;

  stype &= ~SV_TYPE_LOCAL_LIST_ONLY;

  if (stype & SV_TYPE_DOMAIN_ENUM) 
  {
    /* See if we can find the workgroup on this subnet. */
    if(( work = find_workgroup_on_subnet( call_subrec, sname )) != NULL)
    {
      /* We already know about this workgroup - update the ttl. */
      update_workgroup_ttl( work, lp_max_ttl() );
    }
    else
    {
      /* Create the workgroup on the subnet. */
      create_workgroup_on_subnet( call_subrec, sname, lp_max_ttl() );
    }
  }
  else
  {
    /* Server entry. */
    struct server_record *servrec;

    work = call_work;

    if(( servrec = find_server_in_workgroup( work, sname )) != NULL)
    {
      /* Check that this is not a locally known server - if so ignore the
         entry. */
      if(!(servrec->serv.type & SV_TYPE_LOCAL_LIST_ONLY))
      {
        /* We already know about this server - update the ttl. */
        update_server_ttl(servrec, lp_max_ttl() );
        /* Update the type. */
        servrec->serv.type = stype;
      }
    }
    else
    {
      /* Create the server in the workgroup. */ 
      create_server_on_workgroup(work, sname,stype,lp_max_ttl(),comment);
    }
  }
}

/*******************************************************************
  Synchronise browse lists with another browse server.
  Log in on the remote server's SMB port to their IPC$ service,
  do a NetServerEnum and update our server and workgroup databases.
******************************************************************/

static void sync_browse_lists(struct subnet_record *subrec, struct work_record *work,
		       char *name, int nm_type, struct in_addr ip, BOOL local)
{
  extern fstring local_machine;
  static struct cli_state cli;
  uint32 local_type = local ? SV_TYPE_LOCAL_LIST_ONLY : 0;

  DEBUG(2,("%s: sync_browse_lists: Sync browse lists with server %s<%02x> at IP %s for workgroup %s\n",
     timestring(), name, nm_type, inet_ntoa(ip), work->work_group ));

  /* Check we're not trying to sync with ourselves. This can happen if we are
     a domain *and* a local master browser. */
  if(ismyip(ip))
  {
    DEBUG(2,("sync_browse_lists: We are both a domain and a local master browser for workgroup %s. \
Do not sync with ourselves.\n", work->work_group ));
    return;
  }

  if (!cli_initialise(&cli) || !cli_connect(&cli, name, &ip))
  {
    DEBUG(0,("sync_browse_lists: Failed to start browse sync with %s\n", name));
    return;
  }

  if (!cli_session_request(&cli, name, nm_type, local_machine))
  {
    DEBUG(0,("sync_browse_lists: %s rejected the browse sync session\n",name));
    cli_shutdown(&cli);
    return;
  }

  if (!cli_negprot(&cli))
  {
    DEBUG(0,("sync_browse_lists: %s rejected the negprot\n",name));
    cli_shutdown(&cli);
    return;
  }

  if (!cli_session_setup(&cli, "", "", 1, "", 0, work->work_group))
  {
    DEBUG(0,("sync_browse_lists: %s rejected the browse sync sessionsetup\n", 
             name));
    cli_shutdown(&cli);
    return;
  }

  if (!cli_send_tconX(&cli, "IPC$", "IPC", "", 1))
  {
    DEBUG(0,("sync_browse_lists: %s refused browse sync IPC$ connect\n", name));
    cli_shutdown(&cli);
    return;
  }

  call_work = work;
  call_subrec = subrec;

  /* Fetch a workgroup list. */
  cli_NetServerEnum(&cli, work->work_group, 
                    local_type|SV_TYPE_DOMAIN_ENUM,
                    callback);

  /* Now fetch a server list. */
  cli_NetServerEnum(&cli, work->work_group, 
                    local?SV_TYPE_LOCAL_LIST_ONLY:SV_TYPE_ALL,
                    callback);

  cli_shutdown(&cli);
}

/****************************************************************************
As a domain master browser, do a sync with a local master browser.
**************************************************************************/

static void sync_with_lmb(struct browse_cache_record *browc)
{                     
  struct work_record *work;

  if (!(work = find_workgroup_on_subnet(unicast_subnet, browc->work_group))) {
      DEBUG(0, ("sync_with_lmb: failed to get a \
workgroup for a local master browser cache entry workgroup %s, server %s\n", 
                browc->work_group, browc->lmb_name));
      return;
  }

  /* We should only be doing this if we are a domain master browser for
     the given workgroup. Ensure this is so. */

  if(!AM_DOMAIN_MASTER_BROWSER(work))
  {
    DEBUG(0,("sync_with_lmb: We are trying to sync with a local master browser %s \
for workgroup %s and we are not a domain master browser on this workgroup. Error !\n",
        browc->lmb_name, browc->work_group));
    return;
  }

  DEBUG(2, ("sync_with_lmb: Initiating sync with local master browser %s<0x20> at IP %s for \
workgroup %s\n", browc->lmb_name, inet_ntoa(browc->ip), browc->work_group));

  sync_browse_lists(unicast_subnet, work, browc->lmb_name, 0x20, browc->ip, True);

  browc->sync_time += (CHECK_TIME_DMB_TO_LMB_SYNC * 60);
}

/****************************************************************************
Sync or expire any local master browsers.
**************************************************************************/

void dmb_expire_and_sync_browser_lists(time_t t)
{
  static time_t last_run = 0;
  struct browse_cache_record *browc;

  /* Only do this every 20 seconds. */  
  if (t - last_run < 20) 
   return;

  last_run = t;

  expire_lmb_browsers(t);

  for (browc = lmb_browserlist; browc; browc = browc->next)
  {
    if (browc->sync_time < t)
      sync_with_lmb(browc);
  }
}

/****************************************************************************
As a local master browser, send an announce packet to the domain master browser.
**************************************************************************/

static void announce_local_master_browser_to_domain_master_browser( struct work_record *work)
{
  pstring outbuf;
  char *p;

  if(ismyip(work->dmb_addr))
  {
    DEBUG(2,("announce_local_master_browser_to_domain_master_browser: We are both a domain \
and a local master browser for workgroup %s. \
Do not announce to ourselves.\n", work->work_group ));
    return;
  }

  bzero(outbuf,sizeof(outbuf));
  p = outbuf;
  CVAL(p,0) = ANN_MasterAnnouncement;
  p++;

  StrnCpy(p,myname,15);
  strupper(p);
  p = skip_string(p,1);

  DEBUG(4,("announce_local_master_browser_to_domain_master_browser: Sending local master announce \
to %s for workgroup %s.\n", namestr(&work->dmb_name), work->work_group ));

  send_mailslot(True, BROWSE_MAILSLOT, outbuf,PTR_DIFF(p,outbuf),
          myname, 0x0, work->dmb_name.name, 0x20, work->dmb_addr, FIRST_SUBNET->myip);

}

/****************************************************************************
As a local master browser, do a sync with a domain master browser.
**************************************************************************/

static void sync_with_dmb(struct work_record *work)
{
  DEBUG(2, ("sync_with_dmb: Initiating sync with domain master browser %s at IP %s for \
workgroup %s\n", namestr(&work->dmb_name), inet_ntoa(work->dmb_addr), work->work_group));

  sync_browse_lists(unicast_subnet, work, work->dmb_name.name, work->dmb_name.name_type, 
                    work->dmb_addr, False);
}

/****************************************************************************
  Function called when a node status query to a domain master browser IP succeeds.
****************************************************************************/

static void domain_master_node_status_success(struct subnet_record *subrec,
                                              struct userdata_struct *userdata,
                                              struct res_rec *answers,
                                              struct in_addr from_ip)
{
  struct work_record *work = find_workgroup_on_subnet( subrec, userdata->data);

  if(work == NULL)
  {
    DEBUG(0,("domain_master_node_status_success: Unable to find workgroup %s on subnet %s.\n",
              userdata->data, subrec->subnet_name));
    return;
  }

  DEBUG(3,("domain_master_node_status_success: Success in node status for workgroup %s from ip %s\n",
            work->work_group, inet_ntoa(from_ip) ));

  /* Go through the list of names found at answers->rdata and look for
     the first SERVER<0x20> name. */

  if(answers->rdata != NULL)
  {
    char *p = answers->rdata;
    int numnames = CVAL(p, 0);

    p += 1;

    while (numnames--)
    {
      char qname[17];
      uint16 nb_flags;
      int name_type;

      StrnCpy(qname,p,15);
      name_type = CVAL(p,15);
      nb_flags = get_nb_flags(&p[16]);
      trim_string(qname,NULL," ");

      p += 18;

      if(!(nb_flags & NB_GROUP) && (name_type == 0x20))
      {
        struct nmb_name nmbname;

        make_nmb_name(&nmbname, qname, name_type, scope);

        /* Copy the dmb name and IP address
           into the workgroup struct. */

        work->dmb_name = nmbname;
        putip((char *)&work->dmb_addr, &from_ip);

        /* Do the local master browser announcement to the domain
           master browser name and IP. */
        announce_local_master_browser_to_domain_master_browser( work );

        /* Now synchronise lists with the domain master browser. */
        sync_with_dmb(work);
        break;
      }
    }
  }
  else
    DEBUG(0,("domain_master_node_status_success: Failed to find a SERVER<0x20> \
name in reply from IP %s.\n", inet_ntoa(from_ip) ));
}

/****************************************************************************
  Function called when a node status query to a domain master browser IP fails.
****************************************************************************/

static void domain_master_node_status_fail(struct subnet_record *subrec,
                       struct response_record *rrec)
{
  struct userdata_struct *userdata = rrec->userdata;

  DEBUG(0,("domain_master_node_status_fail: Doing a node status request to \
the domain master browser for workgroup %s at IP %s failed. Cannot sync browser \
lists.\n", userdata->data, inet_ntoa(rrec->packet->ip) ));

}

/****************************************************************************
  Function called when a query for a WORKGROUP<1b> name succeeds.
****************************************************************************/

static void find_domain_master_name_query_success(struct subnet_record *subrec,
                        struct userdata_struct *userdata_in,
                        struct nmb_name *q_name, struct in_addr answer_ip, struct res_rec *rrec)
{
  /* 
   * Unfortunately, finding the IP address of the Domain Master Browser,
   * as we have here, is not enough. We need to now do a sync to the
   * SERVERNAME<0x20> NetBIOS name, as only recent NT servers will
   * respond to the SMBSERVER name. To get this name from IP
   * address we do a Node status request, and look for the first
   * NAME<0x20> in the response, and take that as the server name.
   * We also keep a cache of the Domain Master Browser name for this
   * workgroup in the Workgroup struct, so that if the same IP addess
   * is returned every time, we don't need to do the node status
   * request.
   */

  struct work_record *work;
  struct nmb_name nmbname;
  struct userdata_struct *userdata;
  char ud[sizeof(struct userdata_struct) + sizeof(fstring)+1];

  if (!(work = find_workgroup_on_subnet(subrec, q_name->name))) {
      DEBUG(0, ("find_domain_master_name_query_success: failed to find \
workgroup %s\n", q_name->name ));
    return;
  }

  /* First check if we already have a dmb for this workgroup. */

  if(!ip_equal(work->dmb_addr, ipzero) && ip_equal(work->dmb_addr, answer_ip))
  {
    /* Do the local master browser announcement to the domain
       master browser name and IP. */
    announce_local_master_browser_to_domain_master_browser( work );

    /* Now synchronise lists with the domain master browser. */
    sync_with_dmb(work);
    return;
  }
  else
    putip((char *)&work->dmb_addr, &ipzero);

  /* Now initiate the node status request. */
  bzero((char *)&nmbname, sizeof(nmbname));
  nmbname.name[0] = '*';

  /* Put the workgroup name into the userdata so we know
     what workgroup we're talking to when the reply comes
     back. */

  /* Setup the userdata_struct - this is copied so we can use
     a stack variable for this. */
  userdata = (struct userdata_struct *)ud;

  userdata->copy_fn = NULL;
  userdata->free_fn = NULL;
  userdata->userdata_len = strlen(work->work_group)+1;
  strcpy(userdata->data, work->work_group);

  node_status( subrec, &nmbname, answer_ip, 
               domain_master_node_status_success,
               domain_master_node_status_fail,
               userdata);
}

/****************************************************************************
  Function called when a query for a WORKGROUP<1b> name fails.
  ****************************************************************************/
static void find_domain_master_name_query_fail(struct subnet_record *subrec,
                                    struct response_record *rrec,
                                    struct nmb_name *question_name, int fail_code)
{
  DEBUG(0,("find_domain_master_name_query_fail: Unable to find the Domain Master \
Browser name %s for the workgroup %s. Unable to sync browse lists in this workgroup.\n",
        namestr(question_name), question_name->name ));
}

/****************************************************************************
As a local master browser for a workgroup find the domain master browser
name, announce ourselves as local master browser to it and then pull the
full domain browse lists from it onto the given subnet.
**************************************************************************/

void announce_and_sync_with_domain_master_browser( struct subnet_record *subrec,
                                                   struct work_record *work)
{
  struct nmb_name nmbname;

  make_nmb_name(&nmbname,work->work_group,0x1b,scope);

  /* First, query for the WORKGROUP<1b> name from the WINS server. */
  query_name(unicast_subnet, nmbname.name, nmbname.name_type,
             find_domain_master_name_query_success,
             find_domain_master_name_query_fail,
             NULL);

}