source3/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 /* this file handles asynchronous browse synchronisation requests. The
  23    requests are done by forking and putting the result in a file in the
  24    locks directory. We do it this way because we don't want nmbd to be
  25    blocked waiting for some server to respond on a TCP connection. This
  26    also allows us to have more than 1 sync going at once (tridge) */
  27
  28 #include "includes.h"
  29 #include "system/filesys.h"
  30 #include "../librpc/gen_ndr/svcctl.h"
  31 #include "nmbd/nmbd.h"
  32 #include "libsmb/libsmb.h"
  33 #include "libsmb/clirap.h"
  34 #include "../libcli/smb/smbXcli_base.h"
  35
  36 struct sync_record {
  37         struct sync_record *next, *prev;
  38         unstring workgroup;
  39         unstring server;
  40         char *fname;
  41         struct in_addr ip;
  42         pid_t pid;
  43 };
  44
  45 /* a linked list of current sync connections */
  46 static struct sync_record *syncs;
  47
  48 static XFILE *fp;
  49
  50 /*******************************************************************
  51   This is the NetServerEnum callback.
  52   Note sname and comment are in UNIX codepage format.
  53   ******************************************************************/
  54
  55 static void callback(const char *sname, uint32 stype,
  56                      const char *comment, void *state)
  57 {
  58         x_fprintf(fp,"\"%s\" %08X \"%s\"\n", sname, stype, comment);
  59 }
  60
  61 /*******************************************************************
  62   Synchronise browse lists with another browse server.
  63   Log in on the remote server's SMB port to their IPC$ service,
  64   do a NetServerEnum and record the results in fname
  65 ******************************************************************/
  66
  67 static void sync_child(char *name, int nm_type,
  68                        char *workgroup,
  69                        struct in_addr ip, bool local, bool servers,
  70                        char *fname)
  71 {
  72         fstring unix_workgroup;
  73         struct cli_state *cli;
  74         uint32 local_type = local ? SV_TYPE_LOCAL_LIST_ONLY : 0;
  75         struct sockaddr_storage ss;
  76         NTSTATUS status;
  77
  78         /* W2K DMB's return empty browse lists on port 445. Use 139.
  79          * Patch from Andy Levine andyl@epicrealm.com.
  80          */
  81
  82         in_addr_to_sockaddr_storage(&ss, ip);
  83
  84         status = cli_connect_nb(name, &ss, NBT_SMB_PORT, nm_type,
  85                                 get_local_machine_name(), SMB_SIGNING_DEFAULT,
  86                                 0, &cli);
  87         if (!NT_STATUS_IS_OK(status)) {
  88                 return;
  89         }
  90
  91         status = smbXcli_negprot(cli->conn, cli->timeout, PROTOCOL_CORE,
  92                                  PROTOCOL_NT1);
  93         if (!NT_STATUS_IS_OK(status)) {
  94                 cli_shutdown(cli);
  95                 return;
  96         }
  97
  98         if (!NT_STATUS_IS_OK(cli_session_setup(cli, "", "", 1, "", 0,
  99                                                workgroup))) {
 100                 cli_shutdown(cli);
 101                 return;
 102         }
 103
 104         if (!NT_STATUS_IS_OK(cli_tree_connect(cli, "IPC$", "IPC", "", 1))) {
 105                 cli_shutdown(cli);
 106                 return;
 107         }
 108
 109         /* All the cli_XX functions take UNIX character set. */
 110         fstrcpy(unix_workgroup, cli->server_domain ? cli->server_domain : workgroup);
 111
 112         /* Fetch a workgroup list. */
 113         cli_NetServerEnum(cli, unix_workgroup,
 114                           local_type|SV_TYPE_DOMAIN_ENUM,
 115                           callback, NULL);
 116
 117         /* Now fetch a server list. */
 118         if (servers) {
 119                 fstrcpy(unix_workgroup, workgroup);
 120                 cli_NetServerEnum(cli, unix_workgroup,
 121                                   local?SV_TYPE_LOCAL_LIST_ONLY:SV_TYPE_ALL,
 122                                   callback, NULL);
 123         }
 124
 125         cli_shutdown(cli);
 126 }
 127
 128 /*******************************************************************
 129   initialise a browse sync with another browse server.  Log in on the
 130   remote server's SMB port to their IPC$ service, do a NetServerEnum
 131   and record the results
 132 ******************************************************************/
 133
 134 void sync_browse_lists(struct work_record *work,
 135                        char *name, int nm_type,
 136                        struct in_addr ip, bool local, bool servers)
 137 {
 138         struct sync_record *s;
 139         static int counter;
 140
 141         /* Check we're not trying to sync with ourselves. This can
 142            happen if we are a domain *and* a local master browser. */
 143         if (ismyip_v4(ip)) {
 144 done:
 145                 return;
 146         }
 147
 148         s = SMB_MALLOC_P(struct sync_record);
 149         if (!s) goto done;
 150
 151         ZERO_STRUCTP(s);
 152
 153         unstrcpy(s->workgroup, work->work_group);
 154         unstrcpy(s->server, name);
 155         s->ip = ip;
 156
 157         if (asprintf(&s->fname, "%s/sync.%d", lp_lock_directory(), counter++) < 0) {
 158                 SAFE_FREE(s);
 159                 goto done;
 160         }
 161         /* Safe to use as 0 means no size change. */
 162         all_string_sub(s->fname,"//", "/", 0);
 163
 164         DLIST_ADD(syncs, s);
 165
 166         /* the parent forks and returns, leaving the child to do the
 167            actual sync */
 168         CatchChild();
 169         if ((s->pid = fork())) return;
 170
 171         BlockSignals( False, SIGTERM );
 172
 173         DEBUG(2,("Initiating browse sync for %s to %s(%s)\n",
 174                  work->work_group, name, inet_ntoa(ip)));
 175
 176         fp = x_fopen(s->fname,O_WRONLY|O_CREAT|O_TRUNC, 0644);
 177         if (!fp) {
 178                 _exit(1);
 179         }
 180
 181         sync_child(name, nm_type, work->work_group, ip, local, servers,
 182                    s->fname);
 183
 184         x_fclose(fp);
 185         _exit(0);
 186 }
 187
 188 /**********************************************************************
 189  Handle one line from a completed sync file.
 190  **********************************************************************/
 191
 192 static void complete_one(struct sync_record *s,
 193                          char *sname, uint32 stype, char *comment)
 194 {
 195         struct work_record *work;
 196         struct server_record *servrec;
 197
 198         stype &= ~SV_TYPE_LOCAL_LIST_ONLY;
 199
 200         if (stype & SV_TYPE_DOMAIN_ENUM) {
 201                 /* See if we can find the workgroup on this subnet. */
 202                 if((work=find_workgroup_on_subnet(unicast_subnet, sname))) {
 203                         /* We already know about this workgroup -
 204                            update the ttl. */
 205                         update_workgroup_ttl(work,lp_max_ttl());
 206                 } else {
 207                         /* Create the workgroup on the subnet. */
 208                         work = create_workgroup_on_subnet(unicast_subnet,
 209                                                           sname, lp_max_ttl());
 210                         if (work) {
 211                                 /* remember who the master is */
 212                                 unstrcpy(work->local_master_browser_name, comment);
 213                         }
 214                 }
 215                 return;
 216         }
 217
 218         work = find_workgroup_on_subnet(unicast_subnet, s->workgroup);
 219         if (!work) {
 220                 DEBUG(3,("workgroup %s doesn't exist on unicast subnet?\n",
 221                          s->workgroup));
 222                 return;
 223         }
 224
 225         if ((servrec = find_server_in_workgroup( work, sname))) {
 226                 /* Check that this is not a locally known
 227                    server - if so ignore the entry. */
 228                 if(!(servrec->serv.type & SV_TYPE_LOCAL_LIST_ONLY)) {
 229                         /* We already know about this server - update
 230                            the ttl. */
 231                         update_server_ttl(servrec, lp_max_ttl());
 232                         /* Update the type. */
 233                         servrec->serv.type = stype;
 234                 }
 235                 return;
 236         }
 237
 238         /* Create the server in the workgroup. */
 239         create_server_on_workgroup(work, sname,stype, lp_max_ttl(), comment);
 240 }
 241
 242 /**********************************************************************
 243  Read the completed sync info.
 244 **********************************************************************/
 245
 246 static void complete_sync(struct sync_record *s)
 247 {
 248         XFILE *f;
 249         char *server;
 250         char *type_str;
 251         unsigned type;
 252         char *comment;
 253         char line[1024];
 254         const char *ptr;
 255         int count=0;
 256
 257         f = x_fopen(s->fname,O_RDONLY, 0);
 258
 259         if (!f)
 260                 return;
 261
 262         while (!x_feof(f)) {
 263                 TALLOC_CTX *frame = NULL;
 264
 265                 if (!fgets_slash(line,sizeof(line),f))
 266                         continue;
 267
 268                 ptr = line;
 269
 270                 frame = talloc_stackframe();
 271                 if (!next_token_talloc(frame,&ptr,&server,NULL) ||
 272                     !next_token_talloc(frame,&ptr,&type_str,NULL) ||
 273                     !next_token_talloc(frame,&ptr,&comment,NULL)) {
 274                         TALLOC_FREE(frame);
 275                         continue;
 276                 }
 277
 278                 sscanf(type_str, "%X", &type);
 279
 280                 complete_one(s, server, type, comment);
 281
 282                 count++;
 283                 TALLOC_FREE(frame);
 284         }
 285         x_fclose(f);
 286
 287         unlink(s->fname);
 288
 289         DEBUG(2,("sync with %s(%s) for workgroup %s completed (%d records)\n",
 290                  s->server, inet_ntoa(s->ip), s->workgroup, count));
 291 }
 292
 293 /**********************************************************************
 294  Check for completion of any of the child processes.
 295 **********************************************************************/
 296
 297 void sync_check_completion(void)
 298 {
 299         struct sync_record *s, *next;
 300
 301         for (s=syncs;s;s=next) {
 302                 next = s->next;
 303                 if (!process_exists_by_pid(s->pid)) {
 304                         /* it has completed - grab the info */
 305                         complete_sync(s);
 306                         DLIST_REMOVE(syncs, s);
 307                         SAFE_FREE(s->fname);
 308                         SAFE_FREE(s);
 309                 }
 310         }
 311 }