source3/nmbd/nmbd_responserecordsdb.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    NBT netbios library routines
   4    Copyright (C) Andrew Tridgell 1994-1998
   5    Copyright (C) Luke Kenneth Casson Leighton 1994-1998
   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 3 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, see <http://www.gnu.org/licenses/>.
  20
  21 */
  22
  23 #include "includes.h"
  24
  25 int num_response_packets = 0;
  26
  27 /***************************************************************************
  28   Add an expected response record into the list
  29   **************************************************************************/
  30
  31 static void add_response_record(struct subnet_record *subrec,
  32                                 struct response_record *rrec)
  33 {
  34         num_response_packets++; /* count of total number of packets still around */
  35
  36         DEBUG(4,("add_response_record: adding response record id:%hu to subnet %s. num_records:%d\n",
  37                 rrec->response_id, subrec->subnet_name, num_response_packets));
  38
  39         DLIST_ADD_END(subrec->responselist, rrec, struct response_record *);
  40 }
  41
  42 /***************************************************************************
  43   Remove an expected response record from the list
  44   **************************************************************************/
  45
  46 void remove_response_record(struct subnet_record *subrec,
  47                                 struct response_record *rrec)
  48 {
  49         /* It is possible this can be called twice,
  50            with a rrec pointer that has been freed. So
  51            before we inderect into rrec, search for it
  52            on the responselist first. Bug #3617. JRA. */
  53
  54         struct response_record *p = NULL;
  55
  56         for (p = subrec->responselist; p; p = p->next) {
  57                 if (p == rrec) {
  58                         break;
  59                 }
  60         }
  61
  62         if (p == NULL) {
  63                 /* We didn't find rrec on the list. */
  64                 return;
  65         }
  66
  67         DLIST_REMOVE(subrec->responselist, rrec);
  68
  69         if(rrec->userdata) {
  70                 if(rrec->userdata->free_fn) {
  71                         (*rrec->userdata->free_fn)(rrec->userdata);
  72                 } else {
  73                         ZERO_STRUCTP(rrec->userdata);
  74                         SAFE_FREE(rrec->userdata);
  75                 }
  76         }
  77
  78         /* Ensure we can delete. */
  79         rrec->packet->locked = False;
  80         free_packet(rrec->packet);
  81
  82         ZERO_STRUCTP(rrec);
  83         SAFE_FREE(rrec);
  84
  85         num_response_packets--; /* count of total number of packets still around */
  86 }
  87
  88 /****************************************************************************
  89   Create a response record for an outgoing packet.
  90   **************************************************************************/
  91
  92 struct response_record *make_response_record( struct subnet_record *subrec,
  93                                               struct packet_struct *p,
  94                                               response_function resp_fn,
  95                                               timeout_response_function timeout_fn,
  96                                               success_function success_fn,
  97                                               fail_function fail_fn,
  98                                               struct userdata_struct *userdata)
  99 {
 100         struct response_record *rrec;
 101         struct nmb_packet *nmb = &p->packet.nmb;
 102
 103         if (!(rrec = SMB_MALLOC_P(struct response_record))) {
 104                 DEBUG(0,("make_response_queue_record: malloc fail for response_record.\n"));
 105                 return NULL;
 106         }
 107
 108         memset((char *)rrec, '\0', sizeof(*rrec));
 109
 110         rrec->response_id = nmb->header.name_trn_id;
 111
 112         rrec->resp_fn = resp_fn;
 113         rrec->timeout_fn = timeout_fn;
 114         rrec->success_fn = success_fn;
 115         rrec->fail_fn = fail_fn;
 116
 117         rrec->packet = p;
 118
 119         if(userdata) {
 120                 /* Intelligent userdata. */
 121                 if(userdata->copy_fn) {
 122                         if((rrec->userdata = (*userdata->copy_fn)(userdata)) == NULL) {
 123                                 DEBUG(0,("make_response_queue_record: copy fail for userdata.\n"));
 124                                 ZERO_STRUCTP(rrec);
 125                                 SAFE_FREE(rrec);
 126                                 return NULL;
 127                         }
 128                 } else {
 129                         /* Primitive userdata, do a memcpy. */
 130                         if((rrec->userdata = (struct userdata_struct *)
 131                                         SMB_MALLOC(sizeof(struct userdata_struct)+userdata->userdata_len)) == NULL) {
 132                                 DEBUG(0,("make_response_queue_record: malloc fail for userdata.\n"));
 133                                 ZERO_STRUCTP(rrec);
 134                                 SAFE_FREE(rrec);
 135                                 return NULL;
 136                         }
 137                         rrec->userdata->copy_fn = userdata->copy_fn;
 138                         rrec->userdata->free_fn = userdata->free_fn;
 139                         rrec->userdata->userdata_len = userdata->userdata_len;
 140                         memcpy(rrec->userdata->data, userdata->data, userdata->userdata_len);
 141                 }
 142         } else {
 143                 rrec->userdata = NULL;
 144         }
 145
 146         rrec->num_msgs = 0;
 147
 148         if(!nmb->header.nm_flags.bcast)
 149                 rrec->repeat_interval = 5; /* 5 seconds for unicast packets. */
 150         else
 151                 rrec->repeat_interval = 1; /* XXXX should be in ms */
 152         rrec->repeat_count = 3; /* 3 retries */
 153         rrec->repeat_time = time(NULL) + rrec->repeat_interval; /* initial retry time */
 154
 155         /* This packet is not being processed. */
 156         rrec->in_expiration_processing = False;
 157
 158         /* Lock the packet so we won't lose it while it's on the list. */
 159         p->locked = True;
 160
 161         add_response_record(subrec, rrec);
 162
 163         return rrec;
 164 }
 165
 166 /****************************************************************************
 167   Find a response in a subnet's name query response list.
 168   **************************************************************************/
 169
 170 static struct response_record *find_response_record_on_subnet(
 171                                 struct subnet_record *subrec, uint16 id)
 172 {
 173         struct response_record *rrec = NULL;
 174
 175         for (rrec = subrec->responselist; rrec; rrec = rrec->next) {
 176                 if (rrec->response_id == id) {
 177                         DEBUG(4, ("find_response_record: found response record id = %hu on subnet %s\n",
 178                                 id, subrec->subnet_name));
 179                         break;
 180                 }
 181         }
 182         return rrec;
 183 }
 184
 185 /****************************************************************************
 186   Find a response in any subnet's name query response list.
 187   **************************************************************************/
 188
 189 struct response_record *find_response_record(struct subnet_record **ppsubrec,
 190                                 uint16 id)
 191 {
 192         struct response_record *rrec = NULL;
 193
 194         for ((*ppsubrec) = FIRST_SUBNET; (*ppsubrec);
 195                                 (*ppsubrec) = NEXT_SUBNET_INCLUDING_UNICAST(*ppsubrec)) {
 196                 if((rrec = find_response_record_on_subnet(*ppsubrec, id)) != NULL)
 197                         return rrec;
 198         }
 199
 200         /* There should never be response records on the remote_broadcast subnet.
 201                         Sanity check to ensure this is so. */
 202         if(remote_broadcast_subnet->responselist != NULL) {
 203                 DEBUG(0,("find_response_record: response record found on subnet %s. This should \
 204 never happen !\n", remote_broadcast_subnet->subnet_name));
 205         }
 206
 207         /* Now check the WINS server subnet if it exists. */
 208         if(wins_server_subnet != NULL) {
 209                 *ppsubrec = wins_server_subnet;
 210                 if((rrec = find_response_record_on_subnet(*ppsubrec, id))!= NULL)
 211                         return rrec;
 212         }
 213
 214         DEBUG(3,("find_response_record: response packet id %hu received with no \
 215 matching record.\n", id));
 216
 217         *ppsubrec = NULL;
 218
 219         return NULL;
 220 }
 221
 222 /****************************************************************************
 223   Check if a refresh is queued for a particular name on a particular subnet.
 224   **************************************************************************/
 225
 226 bool is_refresh_already_queued(struct subnet_record *subrec, struct name_record *namerec)
 227 {
 228         struct response_record *rrec = NULL;
 229
 230         for (rrec = subrec->responselist; rrec; rrec = rrec->next) {
 231                 struct packet_struct *p = rrec->packet;
 232                 struct nmb_packet *nmb = &p->packet.nmb;
 233
 234                 if((nmb->header.opcode == NMB_NAME_REFRESH_OPCODE_8) ||
 235                                 (nmb->header.opcode == NMB_NAME_REFRESH_OPCODE_9)) {
 236                         /* Yes it's a queued refresh - check if the name is correct. */
 237                         if(nmb_name_equal(&nmb->question.question_name, &namerec->name))
 238                         return True;
 239                 }
 240         }
 241
 242         return False;
 243 }