release/src/router/samba/source/nmbd/nmbd_winsproxy.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    NBT netbios routines and daemon - version 2
   5
   6    Copyright (C) Jeremy Allison 1994-1998
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21
  22 */
  23
  24 #include "includes.h"
  25
  26 extern int DEBUGLEVEL;
  27
  28 /****************************************************************************
  29 Function called when the name lookup succeeded.
  30 ****************************************************************************/
  31
  32 static void wins_proxy_name_query_request_success( struct subnet_record *subrec,
  33                         struct userdata_struct *userdata,
  34                         struct nmb_name *nmbname, struct in_addr ip, struct res_rec *rrec)
  35 {
  36   struct packet_struct *original_packet;
  37   struct subnet_record *orig_broadcast_subnet;
  38   struct name_record *namerec;
  39   uint16 nb_flags;
  40   int num_ips;
  41   int i;
  42   int ttl = 3600; /* By default one hour in the cache. */
  43   struct in_addr *iplist;
  44
  45   /* Extract the original packet and the original broadcast subnet from
  46      the userdata. */
  47
  48   memcpy( (char *)&orig_broadcast_subnet, userdata->data, sizeof(struct subnet_record *) );
  49   memcpy( (char *)&original_packet, &userdata->data[sizeof(struct subnet_record *)],
  50           sizeof(struct packet_struct *) );
  51
  52   nb_flags = get_nb_flags( rrec->rdata );
  53
  54   num_ips = rrec->rdlength / 6;
  55   if(num_ips == 0)
  56   {
  57     DEBUG(0,("wins_proxy_name_query_request_success: Invalid number of IP records (0) \
  58 returned for name %s.\n", nmb_namestr(nmbname) ));
  59     return;
  60   }
  61
  62   if(num_ips == 1)
  63     iplist = &ip;
  64   else
  65   {
  66     if((iplist = (struct in_addr *)malloc( num_ips * sizeof(struct in_addr) )) == NULL)
  67     {
  68       DEBUG(0,("wins_proxy_name_query_request_success: malloc fail !\n"));
  69       return;
  70     }
  71
  72     for(i = 0; i < num_ips; i++)
  73       putip( (char *)&iplist[i], (char *)&rrec->rdata[ (i*6) + 2]);
  74   }
  75
  76   /* Add the queried name to the original subnet as a WINS_PROXY_NAME. */
  77
  78   if(rrec == PERMANENT_TTL)
  79     ttl = lp_max_ttl();
  80
  81   namerec = add_name_to_subnet( orig_broadcast_subnet, nmbname->name,
  82                                 nmbname->name_type, nb_flags, ttl,
  83                                 WINS_PROXY_NAME, num_ips, iplist );
  84
  85   if(iplist != &ip)
  86     free((char *)iplist);
  87
  88   /*
  89    * Check that none of the IP addresses we are returning is on the
  90    * same broadcast subnet as the original requesting packet. If it
  91    * is then don't reply (although we still need to add the name
  92    * to the cache) as the actual machine will be replying also
  93    * and we don't want two replies to a broadcast query.
  94    */
  95
  96   if(namerec && original_packet->packet.nmb.header.nm_flags.bcast)
  97   {
  98     for( i = 0; i < namerec->data.num_ips; i++)
  99     {
 100       if( same_net( namerec->data.ip[i],
 101                     orig_broadcast_subnet->myip,
 102                     orig_broadcast_subnet->mask_ip ) )
 103       {
 104         DEBUG( 5, ( "wins_proxy_name_query_request_success: name %s is a WINS \
 105 proxy name and is also on the same subnet (%s) as the requestor. \
 106 Not replying.\n",
 107                     nmb_namestr(&namerec->name),
 108                     orig_broadcast_subnet->subnet_name ) );
 109         return;
 110       }
 111     }
 112   }
 113
 114   /* Finally reply to the original name query. */
 115   reply_netbios_packet(original_packet,                /* Packet to reply to. */
 116                        0,                              /* Result code. */
 117                        NMB_QUERY,                      /* nmbd type code. */
 118                        NMB_NAME_QUERY_OPCODE,          /* opcode. */
 119                        ttl,                            /* ttl. */
 120                        rrec->rdata,                    /* data to send. */
 121                        rrec->rdlength);                /* data length. */
 122 }
 123
 124 /****************************************************************************
 125 Function called when the name lookup failed.
 126 ****************************************************************************/
 127
 128 static void wins_proxy_name_query_request_fail(struct subnet_record *subrec,
 129                                     struct response_record *rrec,
 130                                     struct nmb_name *question_name, int fail_code)
 131 {
 132   DEBUG(4,("wins_proxy_name_query_request_fail: WINS server returned error code %d for lookup \
 133 of name %s.\n", fail_code, nmb_namestr(question_name) ));
 134 }
 135
 136 /****************************************************************************
 137 Function to make a deep copy of the userdata we will need when the WINS
 138 proxy query returns.
 139 ****************************************************************************/
 140
 141 static struct userdata_struct *wins_proxy_userdata_copy_fn(struct userdata_struct *userdata)
 142 {
 143   struct packet_struct *p, *copy_of_p;
 144   struct userdata_struct *new_userdata =
 145         (struct userdata_struct *)malloc( userdata->userdata_len );
 146
 147   if(new_userdata == NULL)
 148     return NULL;
 149
 150   new_userdata->copy_fn = userdata->copy_fn;
 151   new_userdata->free_fn = userdata->free_fn;
 152   new_userdata->userdata_len = userdata->userdata_len;
 153
 154   /* Copy the subnet_record pointer. */
 155   memcpy( new_userdata->data, userdata->data, sizeof(struct subnet_record *) );
 156
 157   /* Extract the pointer to the packet struct */
 158   memcpy((char *)&p, &userdata->data[sizeof(struct subnet_record *)],
 159          sizeof(struct packet_struct *) );
 160
 161   /* Do a deep copy of the packet. */
 162   if((copy_of_p = copy_packet(p)) == NULL)
 163   {
 164     free((char *)new_userdata);
 165     return NULL;
 166   }
 167
 168   /* Lock the copy. */
 169   copy_of_p->locked = True;
 170
 171   memcpy( &new_userdata->data[sizeof(struct subnet_record *)], (char *)&copy_of_p,
 172           sizeof(struct packet_struct *) );
 173
 174   return new_userdata;
 175 }
 176
 177 /****************************************************************************
 178 Function to free the deep copy of the userdata we used when the WINS
 179 proxy query returned.
 180 ****************************************************************************/
 181
 182 static void wins_proxy_userdata_free_fn(struct userdata_struct *userdata)
 183 {
 184   struct packet_struct *p;
 185
 186   /* Extract the pointer to the packet struct */
 187   memcpy((char *)&p, &userdata->data[sizeof(struct subnet_record *)],
 188          sizeof(struct packet_struct *));
 189
 190   /* Unlock the packet. */
 191   p->locked = False;
 192
 193   free_packet(p);
 194   ZERO_STRUCTP(userdata);
 195   free((char *)userdata);
 196 }
 197
 198 /****************************************************************************
 199  Make a WINS query on behalf of a broadcast client name query request.
 200 ****************************************************************************/
 201
 202 void make_wins_proxy_name_query_request( struct subnet_record *subrec,
 203                                          struct packet_struct *incoming_packet,
 204                                          struct nmb_name *question_name)
 205 {
 206   long *ud[(sizeof(struct userdata_struct) + sizeof(struct subrec *) +
 207           sizeof(struct packet_struct *))/sizeof(long *) + 1];
 208   struct userdata_struct *userdata = (struct userdata_struct *)ud;
 209
 210   memset(ud, '\0', sizeof(ud));
 211
 212   userdata->copy_fn = wins_proxy_userdata_copy_fn;
 213   userdata->free_fn = wins_proxy_userdata_free_fn;
 214   userdata->userdata_len = sizeof(ud);
 215   memcpy( userdata->data, (char *)&subrec, sizeof(struct subnet_record *));
 216   memcpy( &userdata->data[sizeof(struct subnet_record *)], (char *)&incoming_packet,
 217           sizeof(struct packet_struct *));
 218
 219   /* Now use the unicast subnet to query the name with the WINS server. */
 220   query_name( unicast_subnet, question_name->name, question_name->name_type,
 221               wins_proxy_name_query_request_success,
 222               wins_proxy_name_query_request_fail,
 223               userdata);
 224 }