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 #include "nmbd/nmbd.h"
  25
  26 int num_response_packets = 0;
  27
  28 /***************************************************************************
  29   Add an expected response record into the list
  30   **************************************************************************/
  31
  32 static void add_response_record(struct subnet_record *subrec,
  33                                 struct response_record *rrec)
  34 {
  35         num_response_packets++; /* count of total number of packets still around */
  36
  37         DEBUG(4,("add_response_record: adding response record id:%hu to subnet %s. num_records:%d\n",
  38                 rrec->response_id, subrec->subnet_name, num_response_packets));
  39
  40         DLIST_ADD_END(subrec->responselist, rrec);
  41 }
  42
  43 /***************************************************************************
  44   Remove an expected response record from the list
  45   **************************************************************************/
  46
  47 void remove_response_record(struct subnet_record *subrec,
  48                                 struct response_record *rrec)
  49 {
  50         /* It is possible this can be called twice,
  51            with a rrec pointer that has been freed. So
  52            before we indirect into rrec, search for it
  53            on the responselist first. Bug #3617. JRA. */
  54
  55         struct response_record *p = NULL;
  56
  57         for (p = subrec->responselist; p; p = p->next) {
  58                 if (p == rrec) {
  59                         break;
  60                 }
  61         }
  62
  63         if (p == NULL) {
  64                 /* We didn't find rrec on the list. */
  65                 return;
  66         }
  67
  68         DLIST_REMOVE(subrec->responselist, rrec);
  69
  70         if(rrec->userdata) {
  71                 if(rrec->userdata->free_fn) {
  72                         (*rrec->userdata->free_fn)(rrec->userdata);
  73                 } else {
  74                         ZERO_STRUCTP(rrec->userdata);
  75                         SAFE_FREE(rrec->userdata);
  76                 }
  77         }
  78
  79         /* Ensure we can delete. */
  80         rrec->packet->locked = False;
  81         free_packet(rrec->packet);
  82
  83         ZERO_STRUCTP(rrec);
  84         SAFE_FREE(rrec);
  85
  86         num_response_packets--; /* count of total number of packets still around */
  87 }
  88
  89 /****************************************************************************
  90   Create a response record for an outgoing packet.
  91   **************************************************************************/
  92
  93 struct response_record *make_response_record( struct subnet_record *subrec,
  94                                               struct packet_struct *p,
  95                                               response_function resp_fn,
  96                                               timeout_response_function timeout_fn,
  97                                               success_function success_fn,
  98                                               fail_function fail_fn,
  99                                               struct userdata_struct *userdata)
 100 {
 101         struct response_record *rrec;
 102         struct nmb_packet *nmb = &p->packet.nmb;
 103
 104         if (!(rrec = SMB_MALLOC_P(struct response_record))) {
 105                 DEBUG(0,("make_response_queue_record: malloc fail for response_record.\n"));
 106                 return NULL;
 107         }
 108
 109         memset((char *)rrec, '\0', sizeof(*rrec));
 110
 111         rrec->response_id = nmb->header.name_trn_id;
 112
 113         rrec->resp_fn = resp_fn;
 114         rrec->timeout_fn = timeout_fn;
 115         rrec->success_fn = success_fn;
 116         rrec->fail_fn = fail_fn;
 117
 118         rrec->packet = p;
 119
 120         if(userdata) {
 121                 /* Intelligent userdata. */
 122                 if(userdata->copy_fn) {
 123                         if((rrec->userdata = (*userdata->copy_fn)(userdata)) == NULL) {
 124                                 DEBUG(0,("make_response_queue_record: copy fail for userdata.\n"));
 125                                 ZERO_STRUCTP(rrec);
 126                                 SAFE_FREE(rrec);
 127                                 return NULL;
 128                         }
 129                 } else {
 130                         /* Primitive userdata, do a memcpy. */
 131                         if((rrec->userdata = (struct userdata_struct *)
 132                                         SMB_MALLOC(sizeof(struct userdata_struct)+userdata->userdata_len)) == NULL) {
 133                                 DEBUG(0,("make_response_queue_record: malloc fail for userdata.\n"));
 134                                 ZERO_STRUCTP(rrec);
 135                                 SAFE_FREE(rrec);
 136                                 return NULL;
 137                         }
 138                         rrec->userdata->copy_fn = userdata->copy_fn;
 139                         rrec->userdata->free_fn = userdata->free_fn;
 140                         rrec->userdata->userdata_len = userdata->userdata_len;
 141                         memcpy(rrec->userdata->data, userdata->data, userdata->userdata_len);
 142                 }
 143         } else {
 144                 rrec->userdata = NULL;
 145         }
 146
 147         rrec->num_msgs = 0;
 148
 149         if(!nmb->header.nm_flags.bcast)
 150                 rrec->repeat_interval = 5; /* 5 seconds for unicast packets. */
 151         else
 152                 rrec->repeat_interval = 1; /* XXXX should be in ms */
 153         rrec->repeat_count = 3; /* 3 retries */
 154         rrec->repeat_time = time(NULL) + rrec->repeat_interval; /* initial retry time */
 155
 156         /* This packet is not being processed. */
 157         rrec->in_expiration_processing = False;
 158
 159         /* Lock the packet so we won't lose it while it's on the list. */
 160         p->locked = True;
 161
 162         add_response_record(subrec, rrec);
 163
 164         return rrec;
 165 }
 166
 167 /****************************************************************************
 168   Find a response in a subnet's name query response list.
 169   **************************************************************************/
 170
 171 static struct response_record *find_response_record_on_subnet(
 172                                 struct subnet_record *subrec, uint16_t id)
 173 {
 174         struct response_record *rrec = NULL;
 175
 176         for (rrec = subrec->responselist; rrec; rrec = rrec->next) {
 177                 if (rrec->response_id == id) {
 178                         DEBUG(4, ("find_response_record: found response record id = %hu on subnet %s\n",
 179                                 id, subrec->subnet_name));
 180                         break;
 181                 }
 182         }
 183         return rrec;
 184 }
 185
 186 /****************************************************************************
 187   Find a response in any subnet's name query response list.
 188   **************************************************************************/
 189
 190 struct response_record *find_response_record(struct subnet_record **ppsubrec,
 191                                 uint16_t id)
 192 {
 193         struct response_record *rrec = NULL;
 194
 195         for ((*ppsubrec) = FIRST_SUBNET; (*ppsubrec);
 196                                 (*ppsubrec) = NEXT_SUBNET_INCLUDING_UNICAST(*ppsubrec)) {
 197                 if((rrec = find_response_record_on_subnet(*ppsubrec, id)) != NULL)
 198                         return rrec;
 199         }
 200
 201         /* There should never be response records on the remote_broadcast subnet.
 202                         Sanity check to ensure this is so. */
 203         if(remote_broadcast_subnet->responselist != NULL) {
 204                 DEBUG(0,("find_response_record: response record found on subnet %s. This should \
 205 never happen !\n", remote_broadcast_subnet->subnet_name));
 206         }
 207
 208         /* Now check the WINS server subnet if it exists. */
 209         if(wins_server_subnet != NULL) {
 210                 *ppsubrec = wins_server_subnet;
 211                 if((rrec = find_response_record_on_subnet(*ppsubrec, id))!= NULL)
 212                         return rrec;
 213         }
 214
 215         DEBUG(3,("find_response_record: response packet id %hu received with no \
 216 matching record.\n", id));
 217
 218         *ppsubrec = NULL;
 219
 220         return NULL;
 221 }
 222
 223 /****************************************************************************
 224   Check if a refresh is queued for a particular name on a particular subnet.
 225   **************************************************************************/
 226
 227 bool is_refresh_already_queued(struct subnet_record *subrec, struct name_record *namerec)
 228 {
 229         struct response_record *rrec = NULL;
 230
 231         for (rrec = subrec->responselist; rrec; rrec = rrec->next) {
 232                 struct packet_struct *p = rrec->packet;
 233                 struct nmb_packet *nmb = &p->packet.nmb;
 234
 235                 if((nmb->header.opcode == NMB_NAME_REFRESH_OPCODE_8) ||
 236                                 (nmb->header.opcode == NMB_NAME_REFRESH_OPCODE_9)) {
 237                         /* Yes it's a queued refresh - check if the name is correct. */
 238                         if(nmb_name_equal(&nmb->question.question_name, &namerec->name))
 239                         return True;
 240                 }
 241         }
 242
 243         return False;
 244 }