source: branches/samba-3.0/source/nmbd/nmbd_synclists.c@ 612

/* 
   Unix SMB/CIFS implementation.
   NBT netbios routines and daemon - version 2
   Copyright (C) Andrew Tridgell 1994-1998
   Copyright (C) Luke Kenneth Casson Leighton 1994-1998
   Copyright (C) Jeremy Allison 1994-1998
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
   
*/

/* this file handles asynchronous browse synchronisation requests. The
   requests are done by forking and putting the result in a file in the
   locks directory. We do it this way because we don't want nmbd to be
   blocked waiting for some server to respond on a TCP connection. This
   also allows us to have more than 1 sync going at once (tridge) */

#include "includes.h"

extern fstring local_machine;

struct sync_record {
        struct sync_record *next, *prev;
        unstring workgroup;
        unstring server;
        pstring fname;
        struct in_addr ip;
        pid_t pid;
};

/* a linked list of current sync connections */
static struct sync_record *syncs;

static XFILE *fp;

/*******************************************************************
  This is the NetServerEnum callback.
  Note sname and comment are in UNIX codepage format.
  ******************************************************************/

static void callback(const char *sname, uint32 stype, 
                     const char *comment, void *state)
{
        x_fprintf(fp,"\"%s\" %08X \"%s\"\n", sname, stype, comment);
}

/*******************************************************************
  Synchronise browse lists with another browse server.
  Log in on the remote server's SMB port to their IPC$ service,
  do a NetServerEnum and record the results in fname
******************************************************************/

static void sync_child(char *name, int nm_type, 
                       char *workgroup,
                       struct in_addr ip, BOOL local, BOOL servers,
                       char *fname)
{
        fstring unix_workgroup;
        struct cli_state *cli;
        uint32 local_type = local ? SV_TYPE_LOCAL_LIST_ONLY : 0;
        struct nmb_name called, calling;
        NTSTATUS status;

        /* W2K DMB's return empty browse lists on port 445. Use 139.
         * Patch from Andy Levine [email protected].
         */

        cli = cli_initialise();
        if (!cli) {
                return;
        }

        if (!cli_set_port(cli, 139)) {
                return;
        }

        status = cli_connect(cli, name, &ip);
        if (!NT_STATUS_IS_OK(status)) {
                return;
        }

        make_nmb_name(&calling, local_machine, 0x0);
        make_nmb_name(&called , name, nm_type);

        if (!cli_session_request(cli, &calling, &called)) {
                cli_shutdown(cli);
                return;
        }

        if (!cli_negprot(cli)) {
                cli_shutdown(cli);
                return;
        }

        if (!NT_STATUS_IS_OK(cli_session_setup(cli, "", "", 1, "", 0,
                                               workgroup))) {
                cli_shutdown(cli);
                return;
        }

        if (!cli_send_tconX(cli, "IPC$", "IPC", "", 1)) {
                cli_shutdown(cli);
                return;
        }

        /* All the cli_XX functions take UNIX character set. */
        fstrcpy(unix_workgroup, cli->server_domain ? cli->server_domain : workgroup);

        /* Fetch a workgroup list. */
        cli_NetServerEnum(cli, unix_workgroup,
                          local_type|SV_TYPE_DOMAIN_ENUM, 
                          callback, NULL);
        
        /* Now fetch a server list. */
        if (servers) {
                fstrcpy(unix_workgroup, workgroup);
                cli_NetServerEnum(cli, unix_workgroup, 
                                  local?SV_TYPE_LOCAL_LIST_ONLY:SV_TYPE_ALL,
                                  callback, NULL);
        }
        
        cli_shutdown(cli);
}

/*******************************************************************
  initialise a browse sync with another browse server.  Log in on the
  remote server's SMB port to their IPC$ service, do a NetServerEnum
  and record the results
******************************************************************/

void sync_browse_lists(struct work_record *work,
                       char *name, int nm_type, 
                       struct in_addr ip, BOOL local, BOOL servers)
{
        struct sync_record *s;
        static int counter;

        START_PROFILE(sync_browse_lists);
        /* Check we're not trying to sync with ourselves. This can
           happen if we are a domain *and* a local master browser. */
        if (ismyip(ip)) {
done:
                END_PROFILE(sync_browse_lists);
                return;
        }

        s = SMB_MALLOC_P(struct sync_record);
        if (!s) goto done;

        ZERO_STRUCTP(s);
        
        unstrcpy(s->workgroup, work->work_group);
        unstrcpy(s->server, name);
        s->ip = ip;

        slprintf(s->fname, sizeof(pstring)-1,
                 "%s/sync.%d", lp_lockdir(), counter++);
        all_string_sub(s->fname,"//", "/", 0);
        
        DLIST_ADD(syncs, s);

        /* the parent forks and returns, leaving the child to do the
           actual sync and call END_PROFILE*/
        CatchChild();
        if ((s->pid = sys_fork())) return;

        BlockSignals( False, SIGTERM );

        DEBUG(2,("Initiating browse sync for %s to %s(%s)\n",
                 work->work_group, name, inet_ntoa(ip)));

        fp = x_fopen(s->fname,O_WRONLY|O_CREAT|O_TRUNC, 0644);
        if (!fp) {
                END_PROFILE(sync_browse_lists);
                _exit(1);       
        }

        sync_child(name, nm_type, work->work_group, ip, local, servers,
                   s->fname);

        x_fclose(fp);
        END_PROFILE(sync_browse_lists);
        _exit(0);
}

/**********************************************************************
 Handle one line from a completed sync file.
 **********************************************************************/

static void complete_one(struct sync_record *s, 
                         char *sname, uint32 stype, char *comment)
{
        struct work_record *work;
        struct server_record *servrec;

        stype &= ~SV_TYPE_LOCAL_LIST_ONLY;

        if (stype & SV_TYPE_DOMAIN_ENUM) {
                /* See if we can find the workgroup on this subnet. */
                if((work=find_workgroup_on_subnet(unicast_subnet, sname))) {
                        /* We already know about this workgroup -
                           update the ttl. */
                        update_workgroup_ttl(work,lp_max_ttl());
                } else {
                        /* Create the workgroup on the subnet. */
                        work = create_workgroup_on_subnet(unicast_subnet, 
                                                          sname, lp_max_ttl());
                        if (work) {
                                /* remember who the master is */
                                unstrcpy(work->local_master_browser_name, comment);
                        }
                }
                return;
        } 

        work = find_workgroup_on_subnet(unicast_subnet, s->workgroup);
        if (!work) {
                DEBUG(3,("workgroup %s doesn't exist on unicast subnet?\n",
                         s->workgroup));
                return;
        }

        if ((servrec = find_server_in_workgroup( work, sname))) {
                /* Check that this is not a locally known
                   server - if so ignore the entry. */
                if(!(servrec->serv.type & SV_TYPE_LOCAL_LIST_ONLY)) {
                        /* We already know about this server - update
                           the ttl. */
                        update_server_ttl(servrec, lp_max_ttl());
                        /* Update the type. */
                        servrec->serv.type = stype;
                }
                return;
        } 

        /* Create the server in the workgroup. */ 
        create_server_on_workgroup(work, sname,stype, lp_max_ttl(), comment);
}
                
/**********************************************************************
 Read the completed sync info.
**********************************************************************/

static void complete_sync(struct sync_record *s)
{
        XFILE *f;
        unstring server, type_str;
        unsigned type;
        pstring comment;
        pstring line;
        const char *ptr;
        int count=0;

        f = x_fopen(s->fname,O_RDONLY, 0);

        if (!f)
                return;
        
        while (!x_feof(f)) {
                
                if (!fgets_slash(line,sizeof(pstring),f))
                        continue;
                
                ptr = line;

                if (!next_token(&ptr,server,NULL,sizeof(server)) ||
                    !next_token(&ptr,type_str,NULL, sizeof(type_str)) ||
                    !next_token(&ptr,comment,NULL, sizeof(comment))) {
                        continue;
                }

                sscanf(type_str, "%X", &type);

                complete_one(s, server, type, comment);

                count++;
        }

        x_fclose(f);

        unlink(s->fname);

        DEBUG(2,("sync with %s(%s) for workgroup %s completed (%d records)\n",
                 s->server, inet_ntoa(s->ip), s->workgroup, count));
}

/**********************************************************************
 Check for completion of any of the child processes.
**********************************************************************/

void sync_check_completion(void)
{
        struct sync_record *s, *next;

        for (s=syncs;s;s=next) {
                next = s->next;
                if (!process_exists_by_pid(s->pid)) {
                        /* it has completed - grab the info */
                        complete_sync(s);
                        DLIST_REMOVE(syncs, s);
                        ZERO_STRUCTP(s);
                        SAFE_FREE(s);
                }
        }
}