/* 
   Unix SMB/Netbios implementation.
   Version 1.9.
   NBT netbios routines and daemon - version 2
   Copyright (C) Andrew Tridgell 1994-1998
   Copyright (C) Luke Kenneth Casson Leighton 1994-1998
   Copyright (C) Jeremy Allison 1994-1998
   
   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"

extern int DEBUGLEVEL;

extern pstring scope;
extern char **my_netbios_names;

uint16 samba_nb_type = 0; /* samba's NetBIOS name type */


/* ************************************************************************** **
 * Set Samba's NetBIOS name type.
 * ************************************************************************** **
 */
void set_samba_nb_type(void)
  {
  if( lp_wins_support() || (*lp_wins_server()) )
    samba_nb_type = NB_MFLAG;               /* samba is a 'hybrid' node type. */
  else
    samba_nb_type = NB_BFLAG;           /* samba is broadcast-only node type. */
  } /* set_samba_nb_type */

/* ************************************************************************** **
 * Returns True if the netbios name is ^1^2__MSBROWSE__^2^1.
 *
 * Note: This name is registered if as a master browser or backup browser
 * you are responsible for a workgroup (when you announce a domain by
 * broadcasting on your local subnet, you announce it as coming from this
 * name: see announce_host()).
 *
 * ************************************************************************** **
 */
BOOL ms_browser_name( char *name, int type )
  {
  return( strequal( name, MSBROWSE ) && (type == 0x01) );
  } /* ms_browser_name */

/* ************************************************************************** **
 * Convert a NetBIOS name to upper case.
 * ************************************************************************** **
 */
static void upcase_name( struct nmb_name *target, struct nmb_name *source )
  {
  int i;

  if( NULL != source )
    (void)memcpy( target, source, sizeof( struct nmb_name ) );

  strupper( target->name );
  strupper( target->scope );

  /* fudge... We're using a byte-by-byte compare, so we must be sure that
   * unused space doesn't have garbage in it.
   */
  for( i = strlen( target->name ); i < sizeof( target->name ); i++ )
    target->name[i] = '\0';
  for( i = strlen( target->scope ); i < sizeof( target->scope ); i++ )
    target->scope[i] = '\0';
  } /* upcase_name */

/* ************************************************************************** **
 * Add a new or overwrite an existing namelist entry.
 * ************************************************************************** **
 */
static void update_name_in_namelist( struct subnet_record *subrec,
                              struct name_record   *namerec )
  {
  struct name_record *oldrec = NULL;

  (void)ubi_trInsert( subrec->namelist, namerec, &(namerec->name), &oldrec );
  if( oldrec )
    {
    if( oldrec->data.ip )
      free( oldrec->data.ip );
    free( oldrec );
    }
  } /* update_name_in_namelist */

/* ************************************************************************** **
 * Remove a name from the namelist.
 * ************************************************************************** **
 */
void remove_name_from_namelist( struct subnet_record *subrec, 
                                struct name_record   *namerec )
  {
  (void)ubi_trRemove( subrec->namelist, namerec );

  if(namerec->data.ip != NULL)
    free((char *)namerec->data.ip);
  free((char *)namerec);

  subrec->namelist_changed = True;
  } /* remove_name_from_namelist */

/* ************************************************************************** **
 * Find a name in a subnet.
 * ************************************************************************** **
 */
struct name_record *find_name_on_subnet( struct subnet_record *subrec,
                                         struct nmb_name      *nmbname,
                                         BOOL                  self_only )
  {
  struct nmb_name     uc_name[1];
  struct name_record *name_ret;

  upcase_name( uc_name, nmbname );
  name_ret = (struct name_record *)ubi_trFind( subrec->namelist, uc_name );
  if( name_ret )
    {
    /* Self names only - these include permanent names. */
    if( self_only
     && (name_ret->data.source != SELF_NAME)
     && (name_ret->data.source != PERMANENT_NAME) )
      {
      DEBUG( 9, 
             ( "find_name_on_subnet: on subnet %s - self name %s NOT FOUND\n",
               subrec->subnet_name, namestr(nmbname) ) );
      return( NULL );
      }
    DEBUG( 9, ("find_name_on_subnet: on subnet %s - found name %s source=%d\n",
               subrec->subnet_name, namestr(nmbname), name_ret->data.source) );
    return( name_ret );
    }
  DEBUG( 9, 
         ( "find_name_on_subnet: on subnet %s - name %s NOT FOUND\n",
           subrec->subnet_name, namestr(nmbname) ) );
  return( NULL );
  } /* find_name_on_subnet */

/* ************************************************************************** **
 * Find a name over all known broadcast subnets.
 * ************************************************************************** **
 */
struct name_record *find_name_for_remote_broadcast_subnet(
                                                   struct nmb_name *nmbname,
                                                   BOOL             self_only )
  {
  struct subnet_record *subrec;
  struct name_record   *namerec = NULL;

  for( subrec = FIRST_SUBNET;
       subrec;
       subrec = NEXT_SUBNET_EXCLUDING_UNICAST(subrec) )
    {
    if( NULL != (namerec = find_name_on_subnet(subrec, nmbname, self_only)) )
      break;
    }

  return( namerec );
  } /* find_name_for_remote_broadcast_subnet */
  
/* ************************************************************************** **
 * Update the ttl of an entry in a subnet name list.
 * ************************************************************************** **
 */
void update_name_ttl( struct name_record *namerec, int ttl )
{
  time_t time_now = time(NULL);

  if( namerec->data.death_time != PERMANENT_TTL )
    namerec->data.death_time = time_now + ttl;

  namerec->data.refresh_time = time_now + (ttl/2);

  namerec->subnet->namelist_changed = True;
} /* update_name_ttl */

/* ************************************************************************** **
 * Add an entry to a subnet name list.
 * ************************************************************************** **
 */
struct name_record *add_name_to_subnet( struct subnet_record *subrec,
                                        char                 *name,
                                        int                   type,
                                        uint16                nb_flags,
                                        int                   ttl,
                                        enum name_source      source,
                                        int                   num_ips,
                                        struct in_addr       *iplist)
{
  struct name_record *namerec;
  time_t time_now = time(NULL);

  namerec = (struct name_record *)malloc( sizeof(*namerec) );
  if( NULL == namerec )
  {
    DEBUG( 0, ( "add_name_to_subnet: malloc fail.\n" ) );
    return( NULL );
  }

  bzero( (char *)namerec, sizeof(*namerec) );
  namerec->data.ip = (struct in_addr *)malloc( sizeof(struct in_addr) 
                                               * num_ips );
  if( NULL == namerec->data.ip )
  {
     DEBUG( 0, ( "add_name_to_subnet: malloc fail when creating ip_flgs.\n" ) );
     free( (char *)namerec );
     return NULL;
  }

  namerec->subnet = subrec;

  make_nmb_name( &namerec->name, name, type, scope );
  upcase_name( &namerec->name, NULL );

  /* Enter the name as active. */
  namerec->data.nb_flags = nb_flags | NB_ACTIVE;

  /* If it's our primary name, flag it as so. */
  if( strequal( my_netbios_names[0], name ) )
    namerec->data.nb_flags |= NB_PERM;

  /* Copy the IPs. */
  namerec->data.num_ips = num_ips;
  memcpy( (namerec->data.ip), iplist, num_ips * sizeof(struct in_addr) );

  /* Data source. */
  namerec->data.source = source;

  /* Setup the death_time and refresh_time. */
  if( ttl == PERMANENT_TTL )
    namerec->data.death_time = PERMANENT_TTL;
  else
    namerec->data.death_time = time_now + ttl;

  namerec->data.refresh_time = time_now + (ttl/2);

  /* Now add the record to the name list. */    
  update_name_in_namelist( subrec, namerec );

  DEBUG( 3, ( "add_name_to_subnet: Added netbios name %s with first IP %s \
ttl=%d nb_flags=%2x to subnet %s\n",
	    namestr( &namerec->name ),
            inet_ntoa( *iplist ),
            ttl,
            (unsigned int)nb_flags,
            subrec->subnet_name ) );

  subrec->namelist_changed = True;

  return(namerec);
}

/*******************************************************************
 Utility function automatically called when a name refresh or register 
 succeeds. By definition this is a SELF_NAME (or we wouldn't be registering
 it).
 ******************************************************************/

void standard_success_register(struct subnet_record *subrec, 
                             struct userdata_struct *userdata,
                             struct nmb_name *nmbname, uint16 nb_flags, int ttl,
                             struct in_addr registered_ip)
{
  struct name_record *namerec;

  namerec = find_name_on_subnet( subrec, nmbname, FIND_SELF_NAME );
  if( NULL == namerec )
    (void)add_name_to_subnet( subrec, nmbname->name, nmbname->name_type,
                              nb_flags, ttl, SELF_NAME, 1, &registered_ip );
  else
    update_name_ttl( namerec, ttl );
}

/*******************************************************************
 Utility function automatically called when a name refresh or register 
 fails.
 ******************************************************************/

void standard_fail_register( struct subnet_record   *subrec,
                             struct response_record *rrec,
                             struct nmb_name        *nmbname )
{
  struct name_record *namerec;

  namerec = find_name_on_subnet( subrec, nmbname, FIND_SELF_NAME );

  DEBUG( 0, ( "standard_fail_register: Failed to register/refresh name %s \
on subnet %s\n",
            namestr(nmbname), subrec->subnet_name) );

  /* Remove the name from the subnet. */
  if( namerec )
    remove_name_from_namelist(subrec, namerec);
}

/*******************************************************************
 Utility function to remove an IP address from a name record.
 ******************************************************************/

static void remove_nth_ip_in_record( struct name_record *namerec, int ind)
{
  if( ind != namerec->data.num_ips )
    memmove( (char *)(&namerec->data.ip[ind]),
             (char *)(&namerec->data.ip[ind+1]), 
             ( namerec->data.num_ips - ind - 1) * sizeof(struct in_addr) );

  namerec->data.num_ips--;
  namerec->subnet->namelist_changed = True;
}

/*******************************************************************
 Utility function to check if an IP address exists in a name record.
 ******************************************************************/

BOOL find_ip_in_name_record( struct name_record *namerec, struct in_addr ip )
{
  int i;

  for(i = 0; i < namerec->data.num_ips; i++)
    if(ip_equal( namerec->data.ip[i], ip))
      return True;

  return False;
}

/*******************************************************************
 Utility function to add an IP address to a name record.
 ******************************************************************/

void add_ip_to_name_record( struct name_record *namerec, struct in_addr new_ip )
{
  struct in_addr *new_list;

  /* Don't add one we already have. */
  if( find_ip_in_name_record( namerec, new_ip ) )
    return;
  
  new_list = (struct in_addr *)malloc( (namerec->data.num_ips + 1)
                                       * sizeof(struct in_addr) );
  if( NULL == new_list )
  {
    DEBUG(0,("add_ip_to_name_record: Malloc fail !\n"));
    return;
  }

  memcpy( (char *)new_list,
          (char *)namerec->data.ip,
          namerec->data.num_ips * sizeof(struct in_addr) );
  new_list[namerec->data.num_ips] = new_ip;

  free((char *)namerec->data.ip);
  namerec->data.ip = new_list;
  namerec->data.num_ips += 1;

  namerec->subnet->namelist_changed = True;
}

/*******************************************************************
 Utility function to remove an IP address from a name record.
 ******************************************************************/

void remove_ip_from_name_record( struct name_record *namerec,
                                 struct in_addr      remove_ip )
{
  /* Try and find the requested ip address - remove it. */
  int i;
  int orig_num = namerec->data.num_ips;

  for(i = 0; i < orig_num; i++)
    if( ip_equal( remove_ip, namerec->data.ip[i]) )
    {
      remove_nth_ip_in_record( namerec, i);
      break;
    }
}

/*******************************************************************
 Utility function that release_name callers can plug into as the
 success function when a name release is successful. Used to save
 duplication of success_function code.
 ******************************************************************/

void standard_success_release( struct subnet_record   *subrec,
                               struct userdata_struct *userdata,
                               struct nmb_name        *nmbname,
                               struct in_addr          released_ip )
{
  struct name_record *namerec;

  namerec = find_name_on_subnet( subrec, nmbname, FIND_ANY_NAME );

  if( namerec == NULL )
  {
    DEBUG( 0, ( "standard_success_release: Name release for name %s IP %s \
on subnet %s. Name was not found on subnet.\n",
                namestr(nmbname),
                inet_ntoa(released_ip),
                subrec->subnet_name) );
    return;
  }
  else
  {
    int orig_num = namerec->data.num_ips;

    remove_ip_from_name_record( namerec, released_ip );

    if( namerec->data.num_ips == orig_num )
      DEBUG( 0, ( "standard_success_release: Name release for name %s IP %s \
on subnet %s. This ip is not known for this name.\n",
                namestr(nmbname),
                inet_ntoa(released_ip),
                subrec->subnet_name ) );
  }

  if( namerec->data.num_ips == 0 )
    remove_name_from_namelist( subrec, namerec );
}

/*******************************************************************
  Expires old names in a subnet namelist.
  ******************************************************************/

void expire_names_on_subnet(struct subnet_record *subrec, time_t t)
{
  struct name_record *namerec;
  struct name_record *next_namerec;

  for( namerec = (struct name_record *)ubi_trFirst( subrec->namelist );
       namerec;
       namerec = next_namerec )
  {
    next_namerec = (struct name_record *)ubi_trNext( namerec );
    if( (namerec->data.death_time != PERMANENT_TTL)
     && (namerec->data.death_time < t) )
    {
      if( namerec->data.source == SELF_NAME )
      {
        DEBUG( 3, ( "expire_names_on_subnet: Subnet %s not expiring SELF \
name %s\n", 
                    subrec->subnet_name, namestr(&namerec->name) ) );
        namerec->data.death_time += 300;
        namerec->subnet->namelist_changed = True;
        continue;
      }
      DEBUG(3,("expire_names_on_subnet: Subnet %s - removing expired name %s\n",
                 subrec->subnet_name, namestr(&namerec->name)));
  
      remove_name_from_namelist( subrec, namerec );
    }
  }
}

/*******************************************************************
  Expires old names in all subnet namelists.
  ******************************************************************/

void expire_names(time_t t)
{
  struct subnet_record *subrec;

  for( subrec = FIRST_SUBNET;
       subrec;
       subrec = NEXT_SUBNET_INCLUDING_UNICAST(subrec) )
  {
    expire_names_on_subnet( subrec, t );
  }
}

/****************************************************************************
  Add the magic samba names, useful for finding samba servers.
  These go directly into the name list for a particular subnet,
  without going through the normal registration process.
  When adding them to the unicast subnet, add them as a list of
  all broadcast subnet IP addresses.
**************************************************************************/

void add_samba_names_to_subnet( struct subnet_record *subrec )
{
  struct in_addr *iplist = &subrec->myip;
  int num_ips = 1;

  /* These names are added permanently (ttl of zero) and will NOT be
     refreshed.  */

  if( (subrec == unicast_subnet)
   || (subrec == wins_server_subnet)
   || (subrec == remote_broadcast_subnet) )
  {
    struct subnet_record *bcast_subrecs;
    int i;
    /* Create an IP list containing all our known subnets. */

    num_ips = iface_count();
    iplist = (struct in_addr *)malloc( num_ips * sizeof(struct in_addr) );
    if( NULL == iplist )
    {
      DEBUG(0,("add_samba_names_to_subnet: Malloc fail !\n"));
      return;
    }

    for( bcast_subrecs = FIRST_SUBNET, i = 0;
         bcast_subrecs; 
         bcast_subrecs = NEXT_SUBNET_EXCLUDING_UNICAST(bcast_subrecs), i++ )
      iplist[i] = bcast_subrecs->myip;

  }

  (void)add_name_to_subnet(subrec,"*",0x0,samba_nb_type, PERMANENT_TTL,
                           PERMANENT_NAME, num_ips, iplist);
  (void)add_name_to_subnet(subrec,"*",0x20,samba_nb_type,PERMANENT_TTL,
                           PERMANENT_NAME, num_ips, iplist);
  (void)add_name_to_subnet(subrec,"__SAMBA__",0x20,samba_nb_type,PERMANENT_TTL,
                           PERMANENT_NAME, num_ips, iplist);
  (void)add_name_to_subnet(subrec,"__SAMBA__",0x00,samba_nb_type,PERMANENT_TTL,
                           PERMANENT_NAME, num_ips, iplist);

  if(iplist != &subrec->myip)
    free((char *)iplist);
}

/****************************************************************************
 Dump the contents of the namelists on all the subnets (including unicast)
 into a file. Initiated by SIGHUP - used to debug the state of the namelists.
**************************************************************************/

static void dump_subnet_namelist( struct subnet_record *subrec, FILE *fp)
{
  struct name_record *namerec;
  char *src_type;
  struct tm *tm;
  int i;

  fprintf(fp, "Subnet %s\n----------------------\n", subrec->subnet_name);
  for( namerec = (struct name_record *)ubi_trFirst( subrec->namelist );
       namerec;
       namerec = (struct name_record *)ubi_trNext( namerec ) )
  {
    fprintf(fp,"\tName = %s\t", namestr(&namerec->name));
    switch(namerec->data.source)
    {
      case LMHOSTS_NAME:
        src_type = "LMHOSTS_NAME";
        break;
      case WINS_PROXY_NAME:
        src_type = "WINS_PROXY_NAME";
        break;
      case REGISTER_NAME:
        src_type = "REGISTER_NAME";
        break;
      case SELF_NAME:
        src_type = "SELF_NAME";
        break;
      case DNS_NAME:
        src_type = "DNS_NAME";
        break;
      case DNSFAIL_NAME:
        src_type = "DNSFAIL_NAME";
        break;
      case PERMANENT_NAME:
        src_type = "PERMANENT_NAME";
        break;
      default:
        src_type = "unknown!";
        break;
    }
    fprintf(fp,"Source = %s\nb_flags = %x\t", src_type, namerec->data.nb_flags);

    if(namerec->data.death_time != PERMANENT_TTL)
    {
      tm = LocalTime(&namerec->data.death_time);
      fprintf(fp, "death_time = %s\t", asctime(tm));
    }
    else
      fprintf(fp, "death_time = PERMANENT\t");

    if(namerec->data.refresh_time != PERMANENT_TTL)
    {
      tm = LocalTime(&namerec->data.refresh_time);
      fprintf(fp, "refresh_time = %s\n", asctime(tm));
    }
    else
      fprintf(fp, "refresh_time = PERMANENT\n");

    fprintf(fp, "\t\tnumber of IPS = %d", namerec->data.num_ips);
    for(i = 0; i < namerec->data.num_ips; i++)
      fprintf(fp, "\t%s", inet_ntoa(namerec->data.ip[i]));

    fprintf(fp, "\n\n");
  }
}

/****************************************************************************
 Dump the contents of the namelists on all the subnets (including unicast)
 into a file. Initiated by SIGHUP - used to debug the state of the namelists.
**************************************************************************/

void dump_all_namelists(void)
{
  pstring fname;
  FILE *fp; 
  struct subnet_record *subrec;

  pstrcpy(fname,lp_lockdir());
  trim_string(fname,NULL,"/");
  pstrcat(fname,"/"); 
  pstrcat(fname,"namelist.debug");

  fp = fopen(fname,"w");
     
  if (!fp)
  { 
    DEBUG(0,("dump_all_namelists: Can't open file %s. Error was %s\n",
              fname,strerror(errno)));
    return;
  }
      
  for( subrec = FIRST_SUBNET;
       subrec;
       subrec = NEXT_SUBNET_INCLUDING_UNICAST(subrec) )
    dump_subnet_namelist( subrec, fp );

  if( !we_are_a_wins_client() )
    dump_subnet_namelist( unicast_subnet, fp );

  if( remote_broadcast_subnet->namelist != NULL )
    dump_subnet_namelist( remote_broadcast_subnet, fp );

  if( wins_server_subnet != NULL )
    dump_subnet_namelist( wins_server_subnet, fp );
  fclose( fp );
}