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 #include "lib/util/string_wrappers.h"
  36 #include "source3/lib/substitute.h"
  37
  38 struct sync_record {
  39         struct sync_record *next, *prev;
  40         unstring workgroup;
  41         unstring server;
  42         char *fname;
  43         struct in_addr ip;
  44         pid_t pid;
  45 };
  46
  47 /* a linked list of current sync connections */
  48 static struct sync_record *syncs;
  49
  50 static FILE *fp;
  51
  52 /*******************************************************************
  53   This is the NetServerEnum callback.
  54   Note sname and comment are in UNIX codepage format.
  55   ******************************************************************/
  56
  57 static void callback(const char *sname, uint32_t stype,
  58                      const char *comment, void *state)
  59 {
  60         fprintf(fp,"\"%s\" %08X \"%s\"\n", sname, stype, comment);
  61 }
  62
  63 /*******************************************************************
  64   Synchronise browse lists with another browse server.
  65   Log in on the remote server's SMB port to their IPC$ service,
  66   do a NetServerEnum and record the results in fname
  67 ******************************************************************/
  68
  69 static void sync_child(char *name, int nm_type,
  70                        char *workgroup,
  71                        struct in_addr ip, bool local, bool servers,
  72                        char *fname)
  73 {
  74         fstring unix_workgroup;
  75         struct cli_state *cli;
  76         uint32_t local_type = local ? SV_TYPE_LOCAL_LIST_ONLY : 0;
  77         struct sockaddr_storage ss;
  78         NTSTATUS status;
  79
  80         /* W2K DMB's return empty browse lists on port 445. Use 139.
  81          * Patch from Andy Levine andyl@epicrealm.com.
  82          */
  83
  84         in_addr_to_sockaddr_storage(&ss, ip);
  85
  86         status = cli_connect_nb(name, &ss, NBT_SMB_PORT, nm_type,
  87                                 get_local_machine_name(), SMB_SIGNING_DEFAULT,
  88                                 0, &cli);
  89         if (!NT_STATUS_IS_OK(status)) {
  90                 return;
  91         }
  92
  93         status = smbXcli_negprot(cli->conn,
  94                                  cli->timeout,
  95                                  PROTOCOL_CORE,
  96                                  PROTOCOL_NT1,
  97                                  NULL,
  98                                  NULL,
  99                                  NULL);
 100         if (!NT_STATUS_IS_OK(status)) {
 101                 cli_shutdown(cli);
 102                 return;
 103         }
 104
 105         status = cli_session_setup_anon(cli);
 106         if (!NT_STATUS_IS_OK(status)) {
 107                 cli_shutdown(cli);
 108                 return;
 109         }
 110
 111         if (!NT_STATUS_IS_OK(cli_tree_connect(cli, "IPC$", "IPC", NULL))) {
 112                 cli_shutdown(cli);
 113                 return;
 114         }
 115
 116         /* All the cli_XX functions take UNIX character set. */
 117         fstrcpy(unix_workgroup, cli->server_domain ? cli->server_domain : workgroup);
 118
 119         /* Fetch a workgroup list. */
 120         cli_NetServerEnum(cli, unix_workgroup,
 121                           local_type|SV_TYPE_DOMAIN_ENUM,
 122                           callback, NULL);
 123
 124         /* Now fetch a server list. */
 125         if (servers) {
 126                 fstrcpy(unix_workgroup, workgroup);
 127                 cli_NetServerEnum(cli, unix_workgroup,
 128                                   local?SV_TYPE_LOCAL_LIST_ONLY:SV_TYPE_ALL,
 129                                   callback, NULL);
 130         }
 131
 132         cli_shutdown(cli);
 133 }
 134
 135 /*******************************************************************
 136   initialise a browse sync with another browse server.  Log in on the
 137   remote server's SMB port to their IPC$ service, do a NetServerEnum
 138   and record the results
 139 ******************************************************************/
 140
 141 void sync_browse_lists(struct work_record *work,
 142                        char *name, int nm_type,
 143                        struct in_addr ip, bool local, bool servers)
 144 {
 145         struct sync_record *s;
 146         static int counter;
 147         int fd;
 148
 149         /* Check we're not trying to sync with ourselves. This can
 150            happen if we are a domain *and* a local master browser. */
 151         if (ismyip_v4(ip)) {
 152 done:
 153                 return;
 154         }
 155
 156         s = SMB_MALLOC_P(struct sync_record);
 157         if (!s) goto done;
 158
 159         ZERO_STRUCTP(s);
 160
 161         unstrcpy(s->workgroup, work->work_group);
 162         unstrcpy(s->server, name);
 163         s->ip = ip;
 164
 165         if (asprintf(&s->fname, "%s/sync.%d", lp_lock_directory(), counter++) < 0) {
 166                 SAFE_FREE(s);
 167                 goto done;
 168         }
 169         /* Safe to use as 0 means no size change. */
 170         all_string_sub(s->fname,"//", "/", 0);
 171
 172         DLIST_ADD(syncs, s);
 173
 174         /* the parent forks and returns, leaving the child to do the
 175            actual sync */
 176         CatchChild();
 177         if ((s->pid = fork())) return;
 178
 179         BlockSignals( False, SIGTERM );
 180
 181         DEBUG(2,("Initiating browse sync for %s to %s(%s)\n",
 182                  work->work_group, name, inet_ntoa(ip)));
 183
 184         fd = open(s->fname, O_WRONLY|O_CREAT|O_TRUNC, 0644);
 185         if (fd == -1) {
 186                 _exit(1);
 187         }
 188
 189         fp = fdopen(fd, "w");
 190         if (!fp) {
 191                 _exit(1);
 192         }
 193         fd = -1;
 194
 195         sync_child(name, nm_type, work->work_group, ip, local, servers,
 196                    s->fname);
 197
 198         fclose(fp);
 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_t 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         FILE *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 = fopen(s->fname, "r");
 272
 273         if (!f)
 274                 return;
 275
 276         while (!feof(f)) {
 277                 TALLOC_CTX *frame = NULL;
 278
 279                 if (!fgets_slash(NULL, 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         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 }