source/nmbd/nmbd_synclists.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    NBT netbios routines and daemon - version 2
   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 /* this file handles asynchronous browse synchronisation requests. The
  24    requests are done by forking and putting the result in a file in the
  25    locks directory. We do it this way because we don't want nmbd to be
  26    blocked waiting for some server to respond on a TCP connection. This
  27    also allows us to have more than 1 sync going at once (tridge) */
  28
  29 #include "includes.h"
  30
  31 struct sync_record {
  32         struct sync_record *next, *prev;
  33         unstring workgroup;
  34         unstring server;
  35         char *fname;
  36         struct in_addr ip;
  37         pid_t pid;
  38 };
  39
  40 /* a linked list of current sync connections */
  41 static struct sync_record *syncs;
  42
  43 static XFILE *fp;
  44
  45 /*******************************************************************
  46   This is the NetServerEnum callback.
  47   Note sname and comment are in UNIX codepage format.
  48   ******************************************************************/
  49
  50 static void callback(const char *sname, uint32 stype,
  51                      const char *comment, void *state)
  52 {
  53         x_fprintf(fp,"\"%s\" %08X \"%s\"\n", sname, stype, comment);
  54 }
  55
  56 /*******************************************************************
  57   Synchronise browse lists with another browse server.
  58   Log in on the remote server's SMB port to their IPC$ service,
  59   do a NetServerEnum and record the results in fname
  60 ******************************************************************/
  61
  62 static void sync_child(char *name, int nm_type,
  63                        char *workgroup,
  64                        struct in_addr ip, bool local, bool servers,
  65                        char *fname)
  66 {
  67         fstring unix_workgroup;
  68         struct cli_state *cli;
  69         uint32 local_type = local ? SV_TYPE_LOCAL_LIST_ONLY : 0;
  70         struct nmb_name called, calling;
  71         struct sockaddr_storage ss;
  72         NTSTATUS status;
  73
  74         /* W2K DMB's return empty browse lists on port 445. Use 139.
  75          * Patch from Andy Levine andyl@epicrealm.com.
  76          */
  77
  78         cli = cli_initialise();
  79         if (!cli) {
  80                 return;
  81         }
  82
  83         if (!cli_set_port(cli, 139)) {
  84                 cli_shutdown(cli);
  85                 return;
  86         }
  87
  88         in_addr_to_sockaddr_storage(&ss, ip);
  89         status = cli_connect(cli, name, &ss);
  90         if (!NT_STATUS_IS_OK(status)) {
  91                 cli_shutdown(cli);
  92                 return;
  93         }
  94
  95         make_nmb_name(&calling, get_local_machine_name(), 0x0);
  96         make_nmb_name(&called , name, nm_type);
  97
  98         if (!cli_session_request(cli, &calling, &called)) {
  99                 cli_shutdown(cli);
 100                 return;
 101         }
 102
 103         if (!cli_negprot(cli)) {
 104                 cli_shutdown(cli);
 105                 return;
 106         }
 107
 108         if (!NT_STATUS_IS_OK(cli_session_setup(cli, "", "", 1, "", 0,
 109                                                workgroup))) {
 110                 cli_shutdown(cli);
 111                 return;
 112         }
 113
 114         if (!cli_send_tconX(cli, "IPC$", "IPC", "", 1)) {
 115                 cli_shutdown(cli);
 116                 return;
 117         }
 118
 119         /* All the cli_XX functions take UNIX character set. */
 120         fstrcpy(unix_workgroup, cli->server_domain ? cli->server_domain : workgroup);
 121
 122         /* Fetch a workgroup list. */
 123         cli_NetServerEnum(cli, unix_workgroup,
 124                           local_type|SV_TYPE_DOMAIN_ENUM,
 125                           callback, NULL);
 126
 127         /* Now fetch a server list. */
 128         if (servers) {
 129                 fstrcpy(unix_workgroup, workgroup);
 130                 cli_NetServerEnum(cli, unix_workgroup,
 131                                   local?SV_TYPE_LOCAL_LIST_ONLY:SV_TYPE_ALL,
 132                                   callback, NULL);
 133         }
 134
 135         cli_shutdown(cli);
 136 }
 137
 138 /*******************************************************************
 139   initialise a browse sync with another browse server.  Log in on the
 140   remote server's SMB port to their IPC$ service, do a NetServerEnum
 141   and record the results
 142 ******************************************************************/
 143
 144 void sync_browse_lists(struct work_record *work,
 145                        char *name, int nm_type,
 146                        struct in_addr ip, bool local, bool servers)
 147 {
 148         struct sync_record *s;
 149         static int counter;
 150
 151         START_PROFILE(sync_browse_lists);
 152         /* Check we're not trying to sync with ourselves. This can
 153            happen if we are a domain *and* a local master browser. */
 154         if (ismyip_v4(ip)) {
 155 done:
 156                 END_PROFILE(sync_browse_lists);
 157                 return;
 158         }
 159
 160         s = SMB_MALLOC_P(struct sync_record);
 161         if (!s) goto done;
 162
 163         ZERO_STRUCTP(s);
 164
 165         unstrcpy(s->workgroup, work->work_group);
 166         unstrcpy(s->server, name);
 167         s->ip = ip;
 168
 169         if (asprintf(&s->fname, "%s/sync.%d", lp_lockdir(), counter++) < 0) {
 170                 SAFE_FREE(s);
 171                 goto done;
 172         }
 173         /* Safe to use as 0 means no size change. */
 174         all_string_sub(s->fname,"//", "/", 0);
 175
 176         DLIST_ADD(syncs, s);
 177
 178         /* the parent forks and returns, leaving the child to do the
 179            actual sync and call END_PROFILE*/
 180         CatchChild();
 181         if ((s->pid = sys_fork())) return;
 182
 183         BlockSignals( False, SIGTERM );
 184
 185         DEBUG(2,("Initiating browse sync for %s to %s(%s)\n",
 186                  work->work_group, name, inet_ntoa(ip)));
 187
 188         fp = x_fopen(s->fname,O_WRONLY|O_CREAT|O_TRUNC, 0644);
 189         if (!fp) {
 190                 END_PROFILE(sync_browse_lists);
 191                 _exit(1);
 192         }
 193
 194         sync_child(name, nm_type, work->work_group, ip, local, servers,
 195                    s->fname);
 196
 197         x_fclose(fp);
 198         END_PROFILE(sync_browse_lists);
 199         _exit(0);
 200 }
 201
 202 /**********************************************************************
 203  Handle one line from a completed sync file.
 204  **********************************************************************/
 205
 206 static void complete_one(struct sync_record *s,
 207                          char *sname, uint32 stype, char *comment)
 208 {
 209         struct work_record *work;
 210         struct server_record *servrec;
 211
 212         stype &= ~SV_TYPE_LOCAL_LIST_ONLY;
 213
 214         if (stype & SV_TYPE_DOMAIN_ENUM) {
 215                 /* See if we can find the workgroup on this subnet. */
 216                 if((work=find_workgroup_on_subnet(unicast_subnet, sname))) {
 217                         /* We already know about this workgroup -
 218                            update the ttl. */
 219                         update_workgroup_ttl(work,lp_max_ttl());
 220                 } else {
 221                         /* Create the workgroup on the subnet. */
 222                         work = create_workgroup_on_subnet(unicast_subnet,
 223                                                           sname, lp_max_ttl());
 224                         if (work) {
 225                                 /* remember who the master is */
 226                                 unstrcpy(work->local_master_browser_name, comment);
 227                         }
 228                 }
 229                 return;
 230         }
 231
 232         work = find_workgroup_on_subnet(unicast_subnet, s->workgroup);
 233         if (!work) {
 234                 DEBUG(3,("workgroup %s doesn't exist on unicast subnet?\n",
 235                          s->workgroup));
 236                 return;
 237         }
 238
 239         if ((servrec = find_server_in_workgroup( work, sname))) {
 240                 /* Check that this is not a locally known
 241                    server - if so ignore the entry. */
 242                 if(!(servrec->serv.type & SV_TYPE_LOCAL_LIST_ONLY)) {
 243                         /* We already know about this server - update
 244                            the ttl. */
 245                         update_server_ttl(servrec, lp_max_ttl());
 246                         /* Update the type. */
 247                         servrec->serv.type = stype;
 248                 }
 249                 return;
 250         }
 251
 252         /* Create the server in the workgroup. */
 253         create_server_on_workgroup(work, sname,stype, lp_max_ttl(), comment);
 254 }
 255
 256 /**********************************************************************
 257  Read the completed sync info.
 258 **********************************************************************/
 259
 260 static void complete_sync(struct sync_record *s)
 261 {
 262         XFILE *f;
 263         char *server;
 264         char *type_str;
 265         unsigned type;
 266         char *comment;
 267         char line[1024];
 268         const char *ptr;
 269         int count=0;
 270
 271         f = x_fopen(s->fname,O_RDONLY, 0);
 272
 273         if (!f)
 274                 return;
 275
 276         while (!x_feof(f)) {
 277                 TALLOC_CTX *frame = NULL;
 278
 279                 if (!fgets_slash(line,sizeof(line),f))
 280                         continue;
 281
 282                 ptr = line;
 283
 284                 frame = talloc_stackframe();
 285                 if (!next_token_talloc(frame,&ptr,&server,NULL) ||
 286                     !next_token_talloc(frame,&ptr,&type_str,NULL) ||
 287                     !next_token_talloc(frame,&ptr,&comment,NULL)) {
 288                         TALLOC_FREE(frame);
 289                         continue;
 290                 }
 291
 292                 sscanf(type_str, "%X", &type);
 293
 294                 complete_one(s, server, type, comment);
 295
 296                 count++;
 297                 TALLOC_FREE(frame);
 298         }
 299         x_fclose(f);
 300
 301         unlink(s->fname);
 302
 303         DEBUG(2,("sync with %s(%s) for workgroup %s completed (%d records)\n",
 304                  s->server, inet_ntoa(s->ip), s->workgroup, count));
 305 }
 306
 307 /**********************************************************************
 308  Check for completion of any of the child processes.
 309 **********************************************************************/
 310
 311 void sync_check_completion(void)
 312 {
 313         struct sync_record *s, *next;
 314
 315         for (s=syncs;s;s=next) {
 316                 next = s->next;
 317                 if (!process_exists_by_pid(s->pid)) {
 318                         /* it has completed - grab the info */
 319                         complete_sync(s);
 320                         DLIST_REMOVE(syncs, s);
 321                         SAFE_FREE(s->fname);
 322                         SAFE_FREE(s);
 323                 }
 324         }
 325 }