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 "lib/util/util_file.h"
  37 #include "source3/lib/substitute.h"
  38
  39 struct sync_record {
  40         struct sync_record *next, *prev;
  41         unstring workgroup;
  42         unstring server;
  43         char *fname;
  44         struct in_addr ip;
  45         pid_t pid;
  46 };
  47
  48 /* a linked list of current sync connections */
  49 static struct sync_record *syncs;
  50
  51 static FILE *fp;
  52
  53 /*******************************************************************
  54   This is the NetServerEnum callback.
  55   Note sname and comment are in UNIX codepage format.
  56   ******************************************************************/
  57
  58 static void callback(const char *sname, uint32_t stype,
  59                      const char *comment, void *state)
  60 {
  61         fprintf(fp,"\"%s\" %08X \"%s\"\n", sname, stype, comment);
  62 }
  63
  64 /*******************************************************************
  65   Synchronise browse lists with another browse server.
  66   Log in on the remote server's SMB port to their IPC$ service,
  67   do a NetServerEnum and record the results in fname
  68 ******************************************************************/
  69
  70 static void sync_child(char *name, int nm_type,
  71                        char *workgroup,
  72                        struct in_addr ip, bool local, bool servers,
  73                        char *fname)
  74 {
  75         fstring unix_workgroup;
  76         struct cli_state *cli;
  77         uint32_t local_type = local ? SV_TYPE_LOCAL_LIST_ONLY : 0;
  78         struct sockaddr_storage ss;
  79         NTSTATUS status;
  80
  81         /* W2K DMB's return empty browse lists on port 445. Use 139.
  82          * Patch from Andy Levine andyl@epicrealm.com.
  83          */
  84
  85         in_addr_to_sockaddr_storage(&ss, ip);
  86
  87         status = cli_connect_nb(talloc_tos(),
  88                                 name,
  89                                 &ss,
  90                                 NBT_SMB_PORT,
  91                                 nm_type,
  92                                 get_local_machine_name(),
  93                                 SMB_SIGNING_DEFAULT,
  94                                 0,
  95                                 &cli);
  96         if (!NT_STATUS_IS_OK(status)) {
  97                 return;
  98         }
  99
 100         status = smbXcli_negprot(cli->conn,
 101                                  cli->timeout,
 102                                  PROTOCOL_CORE,
 103                                  PROTOCOL_NT1,
 104                                  NULL,
 105                                  NULL,
 106                                  NULL);
 107         if (!NT_STATUS_IS_OK(status)) {
 108                 cli_shutdown(cli);
 109                 return;
 110         }
 111
 112         status = cli_session_setup_anon(cli);
 113         if (!NT_STATUS_IS_OK(status)) {
 114                 cli_shutdown(cli);
 115                 return;
 116         }
 117
 118         if (!NT_STATUS_IS_OK(cli_tree_connect(cli, "IPC$", "IPC", NULL))) {
 119                 cli_shutdown(cli);
 120                 return;
 121         }
 122
 123         /* All the cli_XX functions take UNIX character set. */
 124         fstrcpy(unix_workgroup, cli->server_domain ? cli->server_domain : workgroup);
 125
 126         /* Fetch a workgroup list. */
 127         cli_NetServerEnum(cli, unix_workgroup,
 128                           local_type|SV_TYPE_DOMAIN_ENUM,
 129                           callback, NULL);
 130
 131         /* Now fetch a server list. */
 132         if (servers) {
 133                 fstrcpy(unix_workgroup, workgroup);
 134                 cli_NetServerEnum(cli, unix_workgroup,
 135                                   local?SV_TYPE_LOCAL_LIST_ONLY:SV_TYPE_ALL,
 136                                   callback, NULL);
 137         }
 138
 139         cli_shutdown(cli);
 140 }
 141
 142 /*******************************************************************
 143   initialise a browse sync with another browse server.  Log in on the
 144   remote server's SMB port to their IPC$ service, do a NetServerEnum
 145   and record the results
 146 ******************************************************************/
 147
 148 void sync_browse_lists(struct work_record *work,
 149                        char *name, int nm_type,
 150                        struct in_addr ip, bool local, bool servers)
 151 {
 152         struct sync_record *s;
 153         static int counter;
 154         int fd;
 155
 156         /* Check we're not trying to sync with ourselves. This can
 157            happen if we are a domain *and* a local master browser. */
 158         if (ismyip_v4(ip)) {
 159 done:
 160                 return;
 161         }
 162
 163         s = SMB_MALLOC_P(struct sync_record);
 164         if (!s) goto done;
 165
 166         ZERO_STRUCTP(s);
 167
 168         unstrcpy(s->workgroup, work->work_group);
 169         unstrcpy(s->server, name);
 170         s->ip = ip;
 171
 172         if (asprintf(&s->fname, "%s/sync.%d", lp_lock_directory(), counter++) < 0) {
 173                 SAFE_FREE(s);
 174                 goto done;
 175         }
 176         /* Safe to use as 0 means no size change. */
 177         all_string_sub(s->fname,"//", "/", 0);
 178
 179         DLIST_ADD(syncs, s);
 180
 181         /* the parent forks and returns, leaving the child to do the
 182            actual sync */
 183         CatchChild();
 184         if ((s->pid = fork())) return;
 185
 186         BlockSignals( False, SIGTERM );
 187
 188         DEBUG(2,("Initiating browse sync for %s to %s(%s)\n",
 189                  work->work_group, name, inet_ntoa(ip)));
 190
 191         fd = open(s->fname, O_WRONLY|O_CREAT|O_TRUNC, 0644);
 192         if (fd == -1) {
 193                 _exit(1);
 194         }
 195
 196         fp = fdopen(fd, "w");
 197         if (!fp) {
 198                 _exit(1);
 199         }
 200         fd = -1;
 201
 202         sync_child(name, nm_type, work->work_group, ip, local, servers,
 203                    s->fname);
 204
 205         fclose(fp);
 206         _exit(0);
 207 }
 208
 209 /**********************************************************************
 210  Handle one line from a completed sync file.
 211  **********************************************************************/
 212
 213 static void complete_one(struct sync_record *s,
 214                          char *sname, uint32_t stype, char *comment)
 215 {
 216         struct work_record *work;
 217         struct server_record *servrec;
 218
 219         stype &= ~SV_TYPE_LOCAL_LIST_ONLY;
 220
 221         if (stype & SV_TYPE_DOMAIN_ENUM) {
 222                 /* See if we can find the workgroup on this subnet. */
 223                 if((work=find_workgroup_on_subnet(unicast_subnet, sname))) {
 224                         /* We already know about this workgroup -
 225                            update the ttl. */
 226                         update_workgroup_ttl(work,lp_max_ttl());
 227                 } else {
 228                         /* Create the workgroup on the subnet. */
 229                         work = create_workgroup_on_subnet(unicast_subnet,
 230                                                           sname, lp_max_ttl());
 231                         if (work) {
 232                                 /* remember who the master is */
 233                                 unstrcpy(work->local_master_browser_name, comment);
 234                         }
 235                 }
 236                 return;
 237         }
 238
 239         work = find_workgroup_on_subnet(unicast_subnet, s->workgroup);
 240         if (!work) {
 241                 DEBUG(3,("workgroup %s doesn't exist on unicast subnet?\n",
 242                          s->workgroup));
 243                 return;
 244         }
 245
 246         if ((servrec = find_server_in_workgroup( work, sname))) {
 247                 /* Check that this is not a locally known
 248                    server - if so ignore the entry. */
 249                 if(!(servrec->serv.type & SV_TYPE_LOCAL_LIST_ONLY)) {
 250                         /* We already know about this server - update
 251                            the ttl. */
 252                         update_server_ttl(servrec, lp_max_ttl());
 253                         /* Update the type. */
 254                         servrec->serv.type = stype;
 255                 }
 256                 return;
 257         }
 258
 259         /* Create the server in the workgroup. */
 260         create_server_on_workgroup(work, sname,stype, lp_max_ttl(), comment);
 261 }
 262
 263 /**********************************************************************
 264  Read the completed sync info.
 265 **********************************************************************/
 266
 267 static void complete_sync(struct sync_record *s)
 268 {
 269         FILE *f;
 270         char *server;
 271         char *type_str;
 272         unsigned type;
 273         char *comment;
 274         char line[1024];
 275         const char *ptr;
 276         int count=0;
 277
 278         f = fopen(s->fname, "r");
 279
 280         if (!f)
 281                 return;
 282
 283         while (!feof(f)) {
 284                 TALLOC_CTX *frame = NULL;
 285
 286                 if (!fgets_slash(NULL, line, sizeof(line), f))
 287                         continue;
 288
 289                 ptr = line;
 290
 291                 frame = talloc_stackframe();
 292                 if (!next_token_talloc(frame,&ptr,&server,NULL) ||
 293                     !next_token_talloc(frame,&ptr,&type_str,NULL) ||
 294                     !next_token_talloc(frame,&ptr,&comment,NULL)) {
 295                         TALLOC_FREE(frame);
 296                         continue;
 297                 }
 298
 299                 sscanf(type_str, "%X", &type);
 300
 301                 complete_one(s, server, type, comment);
 302
 303                 count++;
 304                 TALLOC_FREE(frame);
 305         }
 306         fclose(f);
 307
 308         unlink(s->fname);
 309
 310         DEBUG(2,("sync with %s(%s) for workgroup %s completed (%d records)\n",
 311                  s->server, inet_ntoa(s->ip), s->workgroup, count));
 312 }
 313
 314 /**********************************************************************
 315  Check for completion of any of the child processes.
 316 **********************************************************************/
 317
 318 void sync_check_completion(void)
 319 {
 320         struct sync_record *s, *next;
 321
 322         for (s=syncs;s;s=next) {
 323                 next = s->next;
 324                 if (!process_exists_by_pid(s->pid)) {
 325                         /* it has completed - grab the info */
 326                         complete_sync(s);
 327                         DLIST_REMOVE(syncs, s);
 328                         SAFE_FREE(s->fname);
 329                         SAFE_FREE(s);
 330                 }
 331         }
 332 }