Beispiel #1
0
static bool canonicalize_connect_path(connection_struct *conn)
{
#ifdef REALPATH_TAKES_NULL
	bool ret;
	char *resolved_name = SMB_VFS_REALPATH(conn,conn->connectpath,NULL);
	if (!resolved_name) {
		return false;
	}
	ret = set_conn_connectpath(conn,resolved_name);
	SAFE_FREE(resolved_name);
	return ret;
#else
        char resolved_name_buf[PATH_MAX+1];
	char *resolved_name = SMB_VFS_REALPATH(conn,conn->connectpath,resolved_name_buf);
	if (!resolved_name) {
		return false;
	}
	return set_conn_connectpath(conn,resolved_name);
#endif /* REALPATH_TAKES_NULL */
}
Beispiel #2
0
static bool canonicalize_connect_path(connection_struct *conn)
{
	bool ret;
	char *resolved_name = SMB_VFS_REALPATH(conn,conn->connectpath);
	if (!resolved_name) {
		return false;
	}
	ret = set_conn_connectpath(conn,resolved_name);
	SAFE_FREE(resolved_name);
	return ret;
}
Beispiel #3
0
connection_struct *make_connection_snum(struct smbd_server_connection *sconn,
					int snum, user_struct *vuser,
					DATA_BLOB password,
					const char *pdev,
					NTSTATUS *pstatus)
{
	connection_struct *conn;
	struct smb_filename *smb_fname_cpath = NULL;
	fstring dev;
	int ret;
	char addr[INET6_ADDRSTRLEN];
	bool on_err_call_dis_hook = false;
	NTSTATUS status;

	fstrcpy(dev, pdev);

	if (NT_STATUS_IS_ERR(*pstatus = share_sanity_checks(snum, dev))) {
		return NULL;
	}	

	conn = conn_new(sconn);
	if (!conn) {
		DEBUG(0,("Couldn't find free connection.\n"));
		*pstatus = NT_STATUS_INSUFFICIENT_RESOURCES;
		return NULL;
	}

	conn->params->service = snum;

	status = create_connection_server_info(sconn,
		conn, snum, vuser ? vuser->server_info : NULL, password,
		&conn->server_info);

	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(1, ("create_connection_server_info failed: %s\n",
			  nt_errstr(status)));
		*pstatus = status;
		conn_free(conn);
		return NULL;
	}

	if ((lp_guest_only(snum)) || (lp_security() == SEC_SHARE)) {
		conn->force_user = true;
	}

	add_session_user(sconn, conn->server_info->unix_name);

	safe_strcpy(conn->client_address,
			client_addr(get_client_fd(),addr,sizeof(addr)), 
			sizeof(conn->client_address)-1);
	conn->num_files_open = 0;
	conn->lastused = conn->lastused_count = time(NULL);
	conn->used = True;
	conn->printer = (strncmp(dev,"LPT",3) == 0);
	conn->ipc = ( (strncmp(dev,"IPC",3) == 0) ||
		      ( lp_enable_asu_support() && strequal(dev,"ADMIN$")) );

	/* Case options for the share. */
	if (lp_casesensitive(snum) == Auto) {
		/* We will be setting this per packet. Set to be case
		 * insensitive for now. */
		conn->case_sensitive = False;
	} else {
		conn->case_sensitive = (bool)lp_casesensitive(snum);
	}

	conn->case_preserve = lp_preservecase(snum);
	conn->short_case_preserve = lp_shortpreservecase(snum);

	conn->encrypt_level = lp_smb_encrypt(snum);

	conn->veto_list = NULL;
	conn->hide_list = NULL;
	conn->veto_oplock_list = NULL;
	conn->aio_write_behind_list = NULL;

	conn->read_only = lp_readonly(SNUM(conn));
	conn->admin_user = False;

	if (*lp_force_user(snum)) {

		/*
		 * Replace conn->server_info with a completely faked up one
		 * from the username we are forced into :-)
		 */

		char *fuser;
		struct auth_serversupplied_info *forced_serverinfo;

		fuser = talloc_string_sub(conn, lp_force_user(snum), "%S",
					  lp_servicename(snum));
		if (fuser == NULL) {
			conn_free(conn);
			*pstatus = NT_STATUS_NO_MEMORY;
			return NULL;
		}

		status = make_serverinfo_from_username(
			conn, fuser, conn->server_info->guest,
			&forced_serverinfo);
		if (!NT_STATUS_IS_OK(status)) {
			conn_free(conn);
			*pstatus = status;
			return NULL;
		}

		TALLOC_FREE(conn->server_info);
		conn->server_info = forced_serverinfo;

		conn->force_user = True;
		DEBUG(3,("Forced user %s\n", fuser));
	}

	/*
	 * If force group is true, then override
	 * any groupid stored for the connecting user.
	 */

	if (*lp_force_group(snum)) {

		status = find_forced_group(
			conn->force_user, snum, conn->server_info->unix_name,
			&conn->server_info->ptok->user_sids[1],
			&conn->server_info->utok.gid);

		if (!NT_STATUS_IS_OK(status)) {
			conn_free(conn);
			*pstatus = status;
			return NULL;
		}

		/*
		 * We need to cache this gid, to use within
 		 * change_to_user() separately from the conn->server_info
 		 * struct. We only use conn->server_info directly if
 		 * "force_user" was set.
 		 */
		conn->force_group_gid = conn->server_info->utok.gid;
	}

	conn->vuid = (vuser != NULL) ? vuser->vuid : UID_FIELD_INVALID;

	{
		char *s = talloc_sub_advanced(talloc_tos(),
					lp_servicename(SNUM(conn)),
					conn->server_info->unix_name,
					conn->connectpath,
					conn->server_info->utok.gid,
					conn->server_info->sanitized_username,
					pdb_get_domain(conn->server_info->sam_account),
					lp_pathname(snum));
		if (!s) {
			conn_free(conn);
			*pstatus = NT_STATUS_NO_MEMORY;
			return NULL;
		}

		if (!set_conn_connectpath(conn,s)) {
			TALLOC_FREE(s);
			conn_free(conn);
			*pstatus = NT_STATUS_NO_MEMORY;
			return NULL;
		}
		DEBUG(3,("Connect path is '%s' for service [%s]\n",s,
			 lp_servicename(snum)));
		TALLOC_FREE(s);
	}

	/*
	 * New code to check if there's a share security descripter
	 * added from NT server manager. This is done after the
	 * smb.conf checks are done as we need a uid and token. JRA.
	 *
	 */

	{
		bool can_write = False;

		can_write = share_access_check(conn->server_info->ptok,
					       lp_servicename(snum),
					       FILE_WRITE_DATA);

		if (!can_write) {
			if (!share_access_check(conn->server_info->ptok,
						lp_servicename(snum),
						FILE_READ_DATA)) {
				/* No access, read or write. */
				DEBUG(0,("make_connection: connection to %s "
					 "denied due to security "
					 "descriptor.\n",
					  lp_servicename(snum)));
				conn_free(conn);
				*pstatus = NT_STATUS_ACCESS_DENIED;
				return NULL;
			} else {
				conn->read_only = True;
			}
		}
	}
	/* Initialise VFS function pointers */

	if (!smbd_vfs_init(conn)) {
		DEBUG(0, ("vfs_init failed for service %s\n",
			  lp_servicename(snum)));
		conn_free(conn);
		*pstatus = NT_STATUS_BAD_NETWORK_NAME;
		return NULL;
	}

	/*
	 * If widelinks are disallowed we need to canonicalise the connect
	 * path here to ensure we don't have any symlinks in the
	 * connectpath. We will be checking all paths on this connection are
	 * below this directory. We must do this after the VFS init as we
	 * depend on the realpath() pointer in the vfs table. JRA.
	 */
	if (!lp_widelinks(snum)) {
		if (!canonicalize_connect_path(conn)) {
			DEBUG(0, ("canonicalize_connect_path failed "
			"for service %s, path %s\n",
				lp_servicename(snum),
				conn->connectpath));
			conn_free(conn);
			*pstatus = NT_STATUS_BAD_NETWORK_NAME;
			return NULL;
		}
	}

	if ((!conn->printer) && (!conn->ipc)) {
		conn->notify_ctx = notify_init(conn, server_id_self(),
					       smbd_messaging_context(),
					       smbd_event_context(),
					       conn);
	}

/* ROOT Activities: */	
	/*
	 * Enforce the max connections parameter.
	 */

	if ((lp_max_connections(snum) > 0)
	    && (count_current_connections(lp_servicename(SNUM(conn)), True) >=
		lp_max_connections(snum))) {

		DEBUG(1, ("Max connections (%d) exceeded for %s\n",
			  lp_max_connections(snum), lp_servicename(snum)));
		conn_free(conn);
		*pstatus = NT_STATUS_INSUFFICIENT_RESOURCES;
		return NULL;
	}  

	/*
	 * Get us an entry in the connections db
	 */
	if (!claim_connection(conn, lp_servicename(snum), 0)) {
		DEBUG(1, ("Could not store connections entry\n"));
		conn_free(conn);
		*pstatus = NT_STATUS_INTERNAL_DB_ERROR;
		return NULL;
	}  

	/* Preexecs are done here as they might make the dir we are to ChDir
	 * to below */
	/* execute any "root preexec = " line */
	if (*lp_rootpreexec(snum)) {
		char *cmd = talloc_sub_advanced(talloc_tos(),
					lp_servicename(SNUM(conn)),
					conn->server_info->unix_name,
					conn->connectpath,
					conn->server_info->utok.gid,
					conn->server_info->sanitized_username,
					pdb_get_domain(conn->server_info->sam_account),
					lp_rootpreexec(snum));
		DEBUG(5,("cmd=%s\n",cmd));
		ret = smbrun(cmd,NULL);
		TALLOC_FREE(cmd);
		if (ret != 0 && lp_rootpreexec_close(snum)) {
			DEBUG(1,("root preexec gave %d - failing "
				 "connection\n", ret));
			yield_connection(conn, lp_servicename(snum));
			conn_free(conn);
			*pstatus = NT_STATUS_ACCESS_DENIED;
			return NULL;
		}
	}

/* USER Activites: */
	if (!change_to_user(conn, conn->vuid)) {
		/* No point continuing if they fail the basic checks */
		DEBUG(0,("Can't become connected user!\n"));
		yield_connection(conn, lp_servicename(snum));
		conn_free(conn);
		*pstatus = NT_STATUS_LOGON_FAILURE;
		return NULL;
	}

	/* Remember that a different vuid can connect later without these
	 * checks... */
	
	/* Preexecs are done here as they might make the dir we are to ChDir
	 * to below */

	/* execute any "preexec = " line */
	if (*lp_preexec(snum)) {
		char *cmd = talloc_sub_advanced(talloc_tos(),
					lp_servicename(SNUM(conn)),
					conn->server_info->unix_name,
					conn->connectpath,
					conn->server_info->utok.gid,
					conn->server_info->sanitized_username,
					pdb_get_domain(conn->server_info->sam_account),
					lp_preexec(snum));
		ret = smbrun(cmd,NULL);
		TALLOC_FREE(cmd);
		if (ret != 0 && lp_preexec_close(snum)) {
			DEBUG(1,("preexec gave %d - failing connection\n",
				 ret));
			*pstatus = NT_STATUS_ACCESS_DENIED;
			goto err_root_exit;
		}
	}

#ifdef WITH_FAKE_KASERVER
	if (lp_afs_share(snum)) {
		afs_login(conn);
	}
#endif
	
	/* Add veto/hide lists */
	if (!IS_IPC(conn) && !IS_PRINT(conn)) {
		set_namearray( &conn->veto_list, lp_veto_files(snum));
		set_namearray( &conn->hide_list, lp_hide_files(snum));
		set_namearray( &conn->veto_oplock_list, lp_veto_oplocks(snum));
		set_namearray( &conn->aio_write_behind_list,
				lp_aio_write_behind(snum));
	}
	
	/* Invoke VFS make connection hook - do this before the VFS_STAT call
	   to allow any filesystems needing user credentials to initialize
	   themselves. */

	if (SMB_VFS_CONNECT(conn, lp_servicename(snum),
			    conn->server_info->unix_name) < 0) {
		DEBUG(0,("make_connection: VFS make connection failed!\n"));
		*pstatus = NT_STATUS_UNSUCCESSFUL;
		goto err_root_exit;
	}

	/* Any error exit after here needs to call the disconnect hook. */
	on_err_call_dis_hook = true;

	status = create_synthetic_smb_fname(talloc_tos(), conn->connectpath,
					    NULL, NULL, &smb_fname_cpath);
	if (!NT_STATUS_IS_OK(status)) {
		*pstatus = status;
		goto err_root_exit;
	}

	/* win2000 does not check the permissions on the directory
	   during the tree connect, instead relying on permission
	   check during individual operations. To match this behaviour
	   I have disabled this chdir check (tridge) */
	/* the alternative is just to check the directory exists */
	if ((ret = SMB_VFS_STAT(conn, smb_fname_cpath)) != 0 ||
	    !S_ISDIR(smb_fname_cpath->st.st_ex_mode)) {
		if (ret == 0 && !S_ISDIR(smb_fname_cpath->st.st_ex_mode)) {
			DEBUG(0,("'%s' is not a directory, when connecting to "
				 "[%s]\n", conn->connectpath,
				 lp_servicename(snum)));
		} else {
			DEBUG(0,("'%s' does not exist or permission denied "
				 "when connecting to [%s] Error was %s\n",
				 conn->connectpath, lp_servicename(snum),
				 strerror(errno) ));
		}
		*pstatus = NT_STATUS_BAD_NETWORK_NAME;
		goto err_root_exit;
	}

	string_set(&conn->origpath,conn->connectpath);

#if SOFTLINK_OPTIMISATION
	/* resolve any soft links early if possible */
	if (vfs_ChDir(conn,conn->connectpath) == 0) {
		TALLOC_CTX *ctx = talloc_tos();
		char *s = vfs_GetWd(ctx,s);
		if (!s) {
			*status = map_nt_error_from_unix(errno);
			goto err_root_exit;
		}
		if (!set_conn_connectpath(conn,s)) {
			*status = NT_STATUS_NO_MEMORY;
			goto err_root_exit;
		}
		vfs_ChDir(conn,conn->connectpath);
	}
#endif

	if (lp_unix_extensions() && lp_widelinks(snum)) {
		DEBUG(0,("Share '%s' has wide links and unix extensions enabled. "
			"These parameters are incompatible. "
			"Disabling wide links for this share.\n",
			lp_servicename(snum) ));
		lp_do_parameter(snum, "wide links", "False");
	}

	/* Figure out the characteristics of the underlying filesystem. This
	 * assumes that all the filesystem mounted withing a share path have
	 * the same characteristics, which is likely but not guaranteed.
	 */

	conn->fs_capabilities = SMB_VFS_FS_CAPABILITIES(conn, &conn->ts_res);

	/*
	 * Print out the 'connected as' stuff here as we need
	 * to know the effective uid and gid we will be using
	 * (at least initially).
	 */

	if( DEBUGLVL( IS_IPC(conn) ? 3 : 1 ) ) {
		dbgtext( "%s (%s) ", get_remote_machine_name(),
			 conn->client_address );
		dbgtext( "%s", srv_is_signing_active(smbd_server_conn) ? "signed " : "");
		dbgtext( "connect to service %s ", lp_servicename(snum) );
		dbgtext( "initially as user %s ",
			 conn->server_info->unix_name );
		dbgtext( "(uid=%d, gid=%d) ", (int)geteuid(), (int)getegid() );
		dbgtext( "(pid %d)\n", (int)sys_getpid() );
	}

	/* we've finished with the user stuff - go back to root */
	change_to_root_user();
	return(conn);

  err_root_exit:
	TALLOC_FREE(smb_fname_cpath);
	change_to_root_user();
	if (on_err_call_dis_hook) {
		/* Call VFS disconnect hook */
		SMB_VFS_DISCONNECT(conn);
	}
	yield_connection(conn, lp_servicename(snum));
	conn_free(conn);
	return NULL;
}
Beispiel #4
0
static NTSTATUS make_connection_snum(struct smbXsrv_connection *xconn,
					connection_struct *conn,
					int snum, struct user_struct *vuser,
					const char *pdev)
{
	struct smbd_server_connection *sconn = xconn->client->sconn;
	struct smb_filename *smb_fname_cpath = NULL;
	fstring dev;
	int ret;
	bool on_err_call_dis_hook = false;
	uid_t effuid;
	gid_t effgid;
	NTSTATUS status;

	fstrcpy(dev, pdev);

	status = share_sanity_checks(sconn->remote_address,
				       sconn->remote_hostname,
				       snum,
				       dev);
	if (NT_STATUS_IS_ERR(status)) {
		goto err_root_exit;
	}

	conn->params->service = snum;

	status = create_connection_session_info(sconn,
		conn, snum, vuser->session_info,
		&conn->session_info);

	if (!NT_STATUS_IS_OK(status)) {
		DEBUG(1, ("create_connection_session_info failed: %s\n",
			  nt_errstr(status)));
		goto err_root_exit;
	}

	if (lp_guest_only(snum)) {
		conn->force_user = true;
	}

	conn->num_files_open = 0;
	conn->lastused = conn->lastused_count = time(NULL);
	conn->printer = (strncmp(dev,"LPT",3) == 0);
	conn->ipc = ( (strncmp(dev,"IPC",3) == 0) ||
		      ( lp_enable_asu_support() && strequal(dev,"ADMIN$")) );

	/* Case options for the share. */
	if (lp_case_sensitive(snum) == Auto) {
		/* We will be setting this per packet. Set to be case
		 * insensitive for now. */
		conn->case_sensitive = False;
	} else {
		conn->case_sensitive = (bool)lp_case_sensitive(snum);
	}

	conn->case_preserve = lp_preserve_case(snum);
	conn->short_case_preserve = lp_short_preserve_case(snum);

	conn->encrypt_level = lp_smb_encrypt(snum);

	conn->veto_list = NULL;
	conn->hide_list = NULL;
	conn->veto_oplock_list = NULL;
	conn->aio_write_behind_list = NULL;

	conn->read_only = lp_read_only(SNUM(conn));

	status = set_conn_force_user_group(conn, snum);
	if (!NT_STATUS_IS_OK(status)) {
		goto err_root_exit;
	}

	conn->vuid = vuser->vuid;

	{
		char *s = talloc_sub_advanced(talloc_tos(),
					lp_servicename(talloc_tos(), SNUM(conn)),
					conn->session_info->unix_info->unix_name,
					conn->connectpath,
					conn->session_info->unix_token->gid,
					conn->session_info->unix_info->sanitized_username,
					conn->session_info->info->domain_name,
					lp_path(talloc_tos(), snum));
		if (!s) {
			status = NT_STATUS_NO_MEMORY;
			goto err_root_exit;
		}

		if (!set_conn_connectpath(conn,s)) {
			TALLOC_FREE(s);
			status = NT_STATUS_NO_MEMORY;
			goto err_root_exit;
		}
		DEBUG(3,("Connect path is '%s' for service [%s]\n",s,
			 lp_servicename(talloc_tos(), snum)));
		TALLOC_FREE(s);
	}

	/*
	 * Set up the share security descriptor.
	 * NOTE - we use the *INCOMING USER* session_info
	 * here, as does (indirectly) change_to_user(),
	 * which can be called on any incoming packet.
	 * This way we set up the share access based
	 * on the authenticated user, not the forced
	 * user. See bug:
	 *
	 * https://bugzilla.samba.org/show_bug.cgi?id=9878
	 */

	status = check_user_share_access(conn,
					vuser->session_info,
					&conn->share_access,
					&conn->read_only);
	if (!NT_STATUS_IS_OK(status)) {
		goto err_root_exit;
	}

	/* Initialise VFS function pointers */

	if (!smbd_vfs_init(conn)) {
		DEBUG(0, ("vfs_init failed for service %s\n",
			  lp_servicename(talloc_tos(), snum)));
		status = NT_STATUS_BAD_NETWORK_NAME;
		goto err_root_exit;
	}

/* ROOT Activities: */
	/* explicitly check widelinks here so that we can correctly warn
	 * in the logs. */
	widelinks_warning(snum);

	/*
	 * Enforce the max connections parameter.
	 */

	if ((lp_max_connections(snum) > 0)
	    && (count_current_connections(lp_servicename(talloc_tos(), SNUM(conn)), True) >=
		lp_max_connections(snum))) {

		DEBUG(1, ("Max connections (%d) exceeded for %s\n",
			  lp_max_connections(snum),
			  lp_servicename(talloc_tos(), snum)));
		status = NT_STATUS_INSUFFICIENT_RESOURCES;
		goto err_root_exit;
	}

	/* Invoke VFS make connection hook - this must be the first
	   filesystem operation that we do. */

	if (SMB_VFS_CONNECT(conn, lp_servicename(talloc_tos(), snum),
			    conn->session_info->unix_info->unix_name) < 0) {
		DBG_WARNING("SMB_VFS_CONNECT for service '%s' at '%s' failed: %s\n",
			    lp_servicename(talloc_tos(), snum), conn->connectpath,
			    strerror(errno));
		status = NT_STATUS_UNSUCCESSFUL;
		goto err_root_exit;
	}

	/* Any error exit after here needs to call the disconnect hook. */
	on_err_call_dis_hook = true;

	if ((!conn->printer) && (!conn->ipc) &&
	    lp_change_notify()) {
		if (sconn->notify_ctx == NULL) {
			sconn->notify_ctx = notify_init(
				sconn, sconn->msg_ctx, sconn->ev_ctx);
			status = messaging_register(
				sconn->msg_ctx, sconn,
				MSG_SMB_NOTIFY_CANCEL_DELETED,
				smbd_notify_cancel_deleted);
		}
		if (sconn->sys_notify_ctx == NULL) {
			sconn->sys_notify_ctx = sys_notify_context_create(
				sconn, sconn->ev_ctx);
		}
	}

	if (lp_kernel_oplocks(snum)) {
		init_kernel_oplocks(conn->sconn);
	}

	/*
	 * Fix compatibility issue pointed out by Volker.
	 * We pass the conn->connectpath to the preexec
	 * scripts as a parameter, so attempt to canonicalize
	 * it here before calling the preexec scripts.
	 * We ignore errors here, as it is possible that
	 * the conn->connectpath doesn't exist yet and
	 * the preexec scripts will create them.
	 */

	(void)canonicalize_connect_path(conn);

	/* Preexecs are done here as they might make the dir we are to ChDir
	 * to below */
	/* execute any "root preexec = " line */
	if (*lp_root_preexec(talloc_tos(), snum)) {
		char *cmd = talloc_sub_advanced(talloc_tos(),
					lp_servicename(talloc_tos(), SNUM(conn)),
					conn->session_info->unix_info->unix_name,
					conn->connectpath,
					conn->session_info->unix_token->gid,
					conn->session_info->unix_info->sanitized_username,
					conn->session_info->info->domain_name,
					lp_root_preexec(talloc_tos(), snum));
		DEBUG(5,("cmd=%s\n",cmd));
		ret = smbrun(cmd,NULL);
		TALLOC_FREE(cmd);
		if (ret != 0 && lp_root_preexec_close(snum)) {
			DEBUG(1,("root preexec gave %d - failing "
				 "connection\n", ret));
			status = NT_STATUS_ACCESS_DENIED;
			goto err_root_exit;
		}
	}

/* USER Activites: */
	if (!change_to_user(conn, conn->vuid)) {
		/* No point continuing if they fail the basic checks */
		DEBUG(0,("Can't become connected user!\n"));
		status = NT_STATUS_LOGON_FAILURE;
		goto err_root_exit;
	}

	effuid = geteuid();
	effgid = getegid();

	/* Remember that a different vuid can connect later without these
	 * checks... */

	/* Preexecs are done here as they might make the dir we are to ChDir
	 * to below */

	/* execute any "preexec = " line */
	if (*lp_preexec(talloc_tos(), snum)) {
		char *cmd = talloc_sub_advanced(talloc_tos(),
					lp_servicename(talloc_tos(), SNUM(conn)),
					conn->session_info->unix_info->unix_name,
					conn->connectpath,
					conn->session_info->unix_token->gid,
					conn->session_info->unix_info->sanitized_username,
					conn->session_info->info->domain_name,
					lp_preexec(talloc_tos(), snum));
		ret = smbrun(cmd,NULL);
		TALLOC_FREE(cmd);
		if (ret != 0 && lp_preexec_close(snum)) {
			DEBUG(1,("preexec gave %d - failing connection\n",
				 ret));
			status = NT_STATUS_ACCESS_DENIED;
			goto err_root_exit;
		}
	}

#ifdef WITH_FAKE_KASERVER
	if (lp_afs_share(snum)) {
		afs_login(conn);
	}
#endif

	/*
	 * we've finished with the user stuff - go back to root
	 * so the SMB_VFS_STAT call will only fail on path errors,
	 * not permission problems.
	 */
	change_to_root_user();
/* ROOT Activites: */

	/*
	 * If widelinks are disallowed we need to canonicalise the connect
	 * path here to ensure we don't have any symlinks in the
	 * connectpath. We will be checking all paths on this connection are
	 * below this directory. We must do this after the VFS init as we
	 * depend on the realpath() pointer in the vfs table. JRA.
	 */
	if (!lp_widelinks(snum)) {
		if (!canonicalize_connect_path(conn)) {
			DEBUG(0, ("canonicalize_connect_path failed "
			"for service %s, path %s\n",
				lp_servicename(talloc_tos(), snum),
				conn->connectpath));
			status = NT_STATUS_BAD_NETWORK_NAME;
			goto err_root_exit;
		}
	}

	/* Add veto/hide lists */
	if (!IS_IPC(conn) && !IS_PRINT(conn)) {
		set_namearray( &conn->veto_list,
			       lp_veto_files(talloc_tos(), snum));
		set_namearray( &conn->hide_list,
			       lp_hide_files(talloc_tos(), snum));
		set_namearray( &conn->veto_oplock_list,
			       lp_veto_oplock_files(talloc_tos(), snum));
		set_namearray( &conn->aio_write_behind_list,
				lp_aio_write_behind(talloc_tos(), snum));
	}
	smb_fname_cpath = synthetic_smb_fname(talloc_tos(), conn->connectpath,
					      NULL, NULL);
	if (smb_fname_cpath == NULL) {
		status = NT_STATUS_NO_MEMORY;
		goto err_root_exit;
	}

	/* win2000 does not check the permissions on the directory
	   during the tree connect, instead relying on permission
	   check during individual operations. To match this behaviour
	   I have disabled this chdir check (tridge) */
	/* the alternative is just to check the directory exists */

	if ((ret = SMB_VFS_STAT(conn, smb_fname_cpath)) != 0 ||
	    !S_ISDIR(smb_fname_cpath->st.st_ex_mode)) {
		if (ret == 0 && !S_ISDIR(smb_fname_cpath->st.st_ex_mode)) {
			DEBUG(0,("'%s' is not a directory, when connecting to "
				 "[%s]\n", conn->connectpath,
				 lp_servicename(talloc_tos(), snum)));
		} else {
			DEBUG(0,("'%s' does not exist or permission denied "
				 "when connecting to [%s] Error was %s\n",
				 conn->connectpath,
				 lp_servicename(talloc_tos(), snum),
				 strerror(errno) ));
		}
		status = NT_STATUS_BAD_NETWORK_NAME;
		goto err_root_exit;
	}
	conn->base_share_dev = smb_fname_cpath->st.st_ex_dev;

	talloc_free(conn->origpath);
	conn->origpath = talloc_strdup(conn, conn->connectpath);

	/* Figure out the characteristics of the underlying filesystem. This
	 * assumes that all the filesystem mounted withing a share path have
	 * the same characteristics, which is likely but not guaranteed.
	 */

	conn->fs_capabilities = SMB_VFS_FS_CAPABILITIES(conn, &conn->ts_res);

	/*
	 * Print out the 'connected as' stuff here as we need
	 * to know the effective uid and gid we will be using
	 * (at least initially).
	 */

	if( DEBUGLVL( IS_IPC(conn) ? 3 : 2 ) ) {
		dbgtext( "%s (%s) ", get_remote_machine_name(),
			 tsocket_address_string(conn->sconn->remote_address,
						talloc_tos()) );
		dbgtext( "%s", srv_is_signing_active(xconn) ? "signed " : "");
		dbgtext( "connect to service %s ",
			 lp_servicename(talloc_tos(), snum) );
		dbgtext( "initially as user %s ",
			 conn->session_info->unix_info->unix_name );
		dbgtext( "(uid=%d, gid=%d) ", (int)effuid, (int)effgid );
		dbgtext( "(pid %d)\n", (int)getpid() );
	}

	return status;

  err_root_exit:

	TALLOC_FREE(smb_fname_cpath);
	/* We must exit this function as root. */
	if (geteuid() != 0) {
		change_to_root_user();
	}
	if (on_err_call_dis_hook) {
		/* Call VFS disconnect hook */
		SMB_VFS_DISCONNECT(conn);
	}
	return status;
}
Beispiel #5
0
static connection_struct *make_connection_snum(int snum, user_struct *vuser,
					       DATA_BLOB password, 
					       const char *pdev,
					       NTSTATUS *status)
{
	struct passwd *pass = NULL;
	BOOL guest = False;
	connection_struct *conn;
	SMB_STRUCT_STAT st;
	fstring user;
	fstring dev;
	int ret;
	struct timespec atime_ts, mtime_ts, ctime_ts;

	*user = 0;
	fstrcpy(dev, pdev);
	SET_STAT_INVALID(st);

	if (NT_STATUS_IS_ERR(*status = share_sanity_checks(snum, dev))) {
		return NULL;
	}	

	conn = conn_new();
	if (!conn) {
		DEBUG(0,("Couldn't find free connection.\n"));
		*status = NT_STATUS_INSUFFICIENT_RESOURCES;
		return NULL;
	}

	conn->params->service = snum;
	conn->nt_user_token = NULL;

	if (lp_guest_only(snum)) {
		const char *guestname = lp_guestaccount();
		NTSTATUS status2;
		char *found_username = NULL;

		guest = True;
		pass = getpwnam_alloc(NULL, guestname);
		if (!pass) {
			DEBUG(0,("make_connection_snum: Invalid guest "
				 "account %s??\n",guestname));
			conn_free(conn);
			*status = NT_STATUS_NO_SUCH_USER;
			return NULL;
		}
		status2 = create_token_from_username(conn->mem_ctx, pass->pw_name, True,
						     &conn->uid, &conn->gid,
						     &found_username,
						     &conn->nt_user_token);
		if (!NT_STATUS_IS_OK(status2)) {
			TALLOC_FREE(pass);
			conn_free(conn);
			*status = status2;
			return NULL;
		}
		fstrcpy(user, found_username);
		string_set(&conn->user,user);
		conn->force_user = True;
		TALLOC_FREE(found_username);
		TALLOC_FREE(pass);
		DEBUG(3,("Guest only user %s\n",user));
	} else if (vuser) {
		if (vuser->guest) {
			if (!lp_guest_ok(snum)) {
				DEBUG(2, ("guest user (from session setup) "
					  "not permitted to access this share "
					  "(%s)\n", lp_servicename(snum)));
				      conn_free(conn);
				      *status = NT_STATUS_ACCESS_DENIED;
				      return NULL;
			}
		} else {
			if (!user_ok_token(vuser->user.unix_name,
					   vuser->nt_user_token, snum)) {
				DEBUG(2, ("user '%s' (from session setup) not "
					  "permitted to access this share "
					  "(%s)\n", vuser->user.unix_name,
					  lp_servicename(snum)));
				conn_free(conn);
				*status = NT_STATUS_ACCESS_DENIED;
				return NULL;
			}
		}
		conn->vuid = vuser->vuid;
		conn->uid = vuser->uid;
		conn->gid = vuser->gid;
		string_set(&conn->user,vuser->user.unix_name);
		fstrcpy(user,vuser->user.unix_name);
		guest = vuser->guest; 
	} else if (lp_security() == SEC_SHARE) {
		NTSTATUS status2;
		char *found_username = NULL;

		/* add it as a possible user name if we 
		   are in share mode security */
		add_session_user(lp_servicename(snum));
		/* shall we let them in? */
		if (!authorise_login(snum,user,password,&guest)) {
			DEBUG( 2, ( "Invalid username/password for [%s]\n", 
				    lp_servicename(snum)) );
			conn_free(conn);
			*status = NT_STATUS_WRONG_PASSWORD;
			return NULL;
		}
		pass = Get_Pwnam(user);
		status2 = create_token_from_username(conn->mem_ctx, pass->pw_name, True,
						     &conn->uid, &conn->gid,
						     &found_username,
						     &conn->nt_user_token);
		if (!NT_STATUS_IS_OK(status2)) {
			conn_free(conn);
			*status = status2;
			return NULL;
		}
		fstrcpy(user, found_username);
		string_set(&conn->user,user);
		TALLOC_FREE(found_username);
		conn->force_user = True;
	} else {
		DEBUG(0, ("invalid VUID (vuser) but not in security=share\n"));
		conn_free(conn);
		*status = NT_STATUS_ACCESS_DENIED;
		return NULL;
	}

	add_session_user(user);

	safe_strcpy(conn->client_address, client_addr(), 
		    sizeof(conn->client_address)-1);
	conn->num_files_open = 0;
	conn->lastused = conn->lastused_count = time(NULL);
	conn->used = True;
	conn->printer = (strncmp(dev,"LPT",3) == 0);
	conn->ipc = ( (strncmp(dev,"IPC",3) == 0) ||
		      ( lp_enable_asu_support() && strequal(dev,"ADMIN$")) );
	conn->dirptr = NULL;

	/* Case options for the share. */
	if (lp_casesensitive(snum) == Auto) {
		/* We will be setting this per packet. Set to be case
		 * insensitive for now. */
		conn->case_sensitive = False;
	} else {
		conn->case_sensitive = (BOOL)lp_casesensitive(snum);
	}

	conn->case_preserve = lp_preservecase(snum);
	conn->short_case_preserve = lp_shortpreservecase(snum);

	conn->veto_list = NULL;
	conn->hide_list = NULL;
	conn->veto_oplock_list = NULL;
	conn->aio_write_behind_list = NULL;
	string_set(&conn->dirpath,"");
	string_set(&conn->user,user);

	conn->read_only = lp_readonly(SNUM(conn));
	conn->admin_user = False;

	/*
	 * If force user is true, then store the given userid and the gid of
	 * the user we're forcing.
	 * For auxiliary groups see below.
	 */
	
	if (*lp_force_user(snum)) {
		NTSTATUS status2;

		status2 = find_forced_user(conn,
				(vuser != NULL) && vuser->guest,
				user);
		if (!NT_STATUS_IS_OK(status2)) {
			conn_free(conn);
			*status = status2;
			return NULL;
		}
		string_set(&conn->user,user);
		conn->force_user = True;
		DEBUG(3,("Forced user %s\n",user));	  
	}

	/*
	 * If force group is true, then override
	 * any groupid stored for the connecting user.
	 */
	
	if (*lp_force_group(snum)) {
		NTSTATUS status2;
		DOM_SID group_sid;

		status2 = find_forced_group(conn->force_user,
					    snum, user,
					    &group_sid, &conn->gid);
		if (!NT_STATUS_IS_OK(status2)) {
			conn_free(conn);
			*status = status2;
			return NULL;
		}

		if ((conn->nt_user_token == NULL) && (vuser != NULL)) {

			/* Not force user and not security=share, but force
			 * group. vuser has a token to copy */
			
			conn->nt_user_token = dup_nt_token(
				NULL, vuser->nt_user_token);
			if (conn->nt_user_token == NULL) {
				DEBUG(0, ("dup_nt_token failed\n"));
				conn_free(conn);
				*status = NT_STATUS_NO_MEMORY;
				return NULL;
			}
		}

		/* If conn->nt_user_token is still NULL, we have
		 * security=share. This means ignore the SID, as we had no
		 * vuser to copy from */

		if (conn->nt_user_token != NULL) {
			/* Overwrite the primary group sid */
			sid_copy(&conn->nt_user_token->user_sids[1],
				 &group_sid);

		}
		conn->force_group = True;
	}

	if (conn->nt_user_token != NULL) {
		size_t i;

		/* We have a share-specific token from force [user|group].
		 * This means we have to create the list of unix groups from
		 * the list of sids. */

		conn->ngroups = 0;
		conn->groups = NULL;

		for (i=0; i<conn->nt_user_token->num_sids; i++) {
			gid_t gid;
			DOM_SID *sid = &conn->nt_user_token->user_sids[i];

			if (!sid_to_gid(sid, &gid)) {
				DEBUG(10, ("Could not convert SID %s to gid, "
					   "ignoring it\n",
					   sid_string_static(sid)));
				continue;
			}
			if (!add_gid_to_array_unique(conn->mem_ctx, gid, &conn->groups,
						&conn->ngroups)) {
				DEBUG(0, ("add_gid_to_array_unique failed\n"));
				conn_free(conn);
				*status = NT_STATUS_NO_MEMORY;
				return NULL;
			}
		}
	}

	{
		pstring s;
		pstrcpy(s,lp_pathname(snum));
		standard_sub_advanced(lp_servicename(SNUM(conn)), conn->user,
				      conn->connectpath, conn->gid,
				      get_current_username(),
				      current_user_info.domain,
				      s, sizeof(s));

		if (s[0] == '\0') {
			DEBUG(6, ("service [%s] did not resolve to a path\n",
				lp_servicename(snum)));
			conn_free(conn);
			*status = NT_STATUS_BAD_NETWORK_NAME;
			return NULL;
		}

		set_conn_connectpath(conn,s);
		DEBUG(3,("Connect path is '%s' for service [%s]\n",s,
			 lp_servicename(snum)));
	}

	/*
	 * New code to check if there's a share security descripter
	 * added from NT server manager. This is done after the
	 * smb.conf checks are done as we need a uid and token. JRA.
	 *
	 */

	{
		BOOL can_write = False;
		NT_USER_TOKEN *token = conn->nt_user_token ?
			conn->nt_user_token :
			(vuser ? vuser->nt_user_token : NULL);

		/*
		 * I don't believe this can happen. But the
		 * logic above is convoluted enough to confuse
		 * automated checkers, so be sure. JRA.
		 */

		if (token == NULL) {
			DEBUG(0,("make_connection: connection to %s "
				 "denied due to missing "
				 "NT token.\n",
				  lp_servicename(snum)));
			conn_free(conn);
			*status = NT_STATUS_ACCESS_DENIED;
			return NULL;
		}

		can_write = share_access_check(token,
						    lp_servicename(snum),
						    FILE_WRITE_DATA);

		if (!can_write) {
			if (!share_access_check(token,
						lp_servicename(snum),
						FILE_READ_DATA)) {
				/* No access, read or write. */
				DEBUG(0,("make_connection: connection to %s "
					 "denied due to security "
					 "descriptor.\n",
					  lp_servicename(snum)));
				conn_free(conn);
				*status = NT_STATUS_ACCESS_DENIED;
				return NULL;
			} else {
				conn->read_only = True;
			}
		}
	}
	/* Initialise VFS function pointers */

	if (!smbd_vfs_init(conn)) {
		DEBUG(0, ("vfs_init failed for service %s\n",
			  lp_servicename(snum)));
		conn_free(conn);
		*status = NT_STATUS_BAD_NETWORK_NAME;
		return NULL;
	}

	/*
	 * If widelinks are disallowed we need to canonicalise the connect
	 * path here to ensure we don't have any symlinks in the
	 * connectpath. We will be checking all paths on this connection are
	 * below this directory. We must do this after the VFS init as we
	 * depend on the realpath() pointer in the vfs table. JRA.
	 */
	if (!lp_widelinks(snum)) {
		pstring s;
		pstrcpy(s,conn->connectpath);
		canonicalize_path(conn, s);
		set_conn_connectpath(conn,s);
	}

	if ((!conn->printer) && (!conn->ipc)) {
		conn->notify_ctx = notify_init(conn->mem_ctx, server_id_self(),
					       smbd_messaging_context(),
					       smbd_event_context(),
					       conn);
	}

/* ROOT Activities: */	
	/* check number of connections */
	if (!claim_connection(conn,
			      lp_servicename(snum),
			      lp_max_connections(snum),
			      False,0)) {
		DEBUG(1,("too many connections - rejected\n"));
		conn_free(conn);
		*status = NT_STATUS_INSUFFICIENT_RESOURCES;
		return NULL;
	}  

	/* Preexecs are done here as they might make the dir we are to ChDir
	 * to below */
	/* execute any "root preexec = " line */
	if (*lp_rootpreexec(snum)) {
		pstring cmd;
		pstrcpy(cmd,lp_rootpreexec(snum));
		standard_sub_advanced(lp_servicename(SNUM(conn)), conn->user,
				      conn->connectpath, conn->gid,
				      get_current_username(),
				      current_user_info.domain,
				      cmd, sizeof(cmd));
		DEBUG(5,("cmd=%s\n",cmd));
		ret = smbrun(cmd,NULL);
		if (ret != 0 && lp_rootpreexec_close(snum)) {
			DEBUG(1,("root preexec gave %d - failing "
				 "connection\n", ret));
			yield_connection(conn, lp_servicename(snum));
			conn_free(conn);
			*status = NT_STATUS_ACCESS_DENIED;
			return NULL;
		}
	}

/* USER Activites: */
	if (!change_to_user(conn, conn->vuid)) {
		/* No point continuing if they fail the basic checks */
		DEBUG(0,("Can't become connected user!\n"));
		yield_connection(conn, lp_servicename(snum));
		conn_free(conn);
		*status = NT_STATUS_LOGON_FAILURE;
		return NULL;
	}

	/* Remember that a different vuid can connect later without these
	 * checks... */
	
	/* Preexecs are done here as they might make the dir we are to ChDir
	 * to below */

	/* execute any "preexec = " line */
	if (*lp_preexec(snum)) {
		pstring cmd;
		pstrcpy(cmd,lp_preexec(snum));
		standard_sub_advanced(lp_servicename(SNUM(conn)), conn->user,
				      conn->connectpath, conn->gid,
				      get_current_username(),
				      current_user_info.domain,
				      cmd, sizeof(cmd));
		ret = smbrun(cmd,NULL);
		if (ret != 0 && lp_preexec_close(snum)) {
			DEBUG(1,("preexec gave %d - failing connection\n",
				 ret));
			change_to_root_user();
			yield_connection(conn, lp_servicename(snum));
			conn_free(conn);
			*status = NT_STATUS_ACCESS_DENIED;
			return NULL;
		}
	}

#ifdef WITH_FAKE_KASERVER
	if (lp_afs_share(snum)) {
		afs_login(conn);
	}
#endif
	
	/* Add veto/hide lists */
	if (!IS_IPC(conn) && !IS_PRINT(conn)) {
		set_namearray( &conn->veto_list, lp_veto_files(snum));
		set_namearray( &conn->hide_list, lp_hide_files(snum));
		set_namearray( &conn->veto_oplock_list, lp_veto_oplocks(snum));
	}
	
	/* Invoke VFS make connection hook - do this before the VFS_STAT call
	   to allow any filesystems needing user credentials to initialize
	   themselves. */

	if (SMB_VFS_CONNECT(conn, lp_servicename(snum), user) < 0) {
		DEBUG(0,("make_connection: VFS make connection failed!\n"));
		change_to_root_user();
		yield_connection(conn, lp_servicename(snum));
		conn_free(conn);
		*status = NT_STATUS_UNSUCCESSFUL;
		return NULL;
	}

	/* win2000 does not check the permissions on the directory
	   during the tree connect, instead relying on permission
	   check during individual operations. To match this behaviour
	   I have disabled this chdir check (tridge) */
	/* the alternative is just to check the directory exists */
	if ((ret = SMB_VFS_STAT(conn, conn->connectpath, &st)) != 0 ||
	    !S_ISDIR(st.st_mode)) {
		if (ret == 0 && !S_ISDIR(st.st_mode)) {
			DEBUG(0,("'%s' is not a directory, when connecting to "
				 "[%s]\n", conn->connectpath,
				 lp_servicename(snum)));
		} else {
			DEBUG(0,("'%s' does not exist or permission denied "
				 "when connecting to [%s] Error was %s\n",
				 conn->connectpath, lp_servicename(snum),
				 strerror(errno) ));
		}
		change_to_root_user();
		/* Call VFS disconnect hook */    
		SMB_VFS_DISCONNECT(conn);
		yield_connection(conn, lp_servicename(snum));
		conn_free(conn);
		*status = NT_STATUS_BAD_NETWORK_NAME;
		return NULL;
	}

	string_set(&conn->origpath,conn->connectpath);

	mtime_ts = get_mtimespec(&st);
	ctime_ts = get_ctimespec(&st);
	atime_ts = get_atimespec(&st);

	conn->ts_res = TIMESTAMP_SET_SECONDS;

	if (mtime_ts.tv_nsec ||
			atime_ts.tv_nsec ||
			ctime_ts.tv_nsec) {
		/* If any of the normal UNIX directory timestamps
		 * have a non-zero tv_nsec component assume
		 * we might be able to set sub-second timestamps.
		 * See what filetime set primitives we have.
		 */
#if defined(HAVE_UTIMES)
		/* utimes allows msec timestamps to be set. */
		conn->ts_res = TIMESTAMP_SET_MSEC;
#elif defined(HAVE_UTIME)
		/* utime only allows sec timestamps to be set. */
		conn->ts_res = TIMESTAMP_SET_SECONDS;
#endif

		/* TODO. Add a configure test for the Linux
		 * nsec timestamp set system call, and use it
		 * if available....
		 */
		DEBUG(10,("make_connection_snum: timestamp "
			"resolution of %s "
			"available on share %s, directory %s\n",
			conn->ts_res == TIMESTAMP_SET_MSEC ? "msec" : "sec",
			lp_servicename(conn->cnum),
			conn->connectpath ));
	}

#if SOFTLINK_OPTIMISATION
	/* resolve any soft links early if possible */
	if (vfs_ChDir(conn,conn->connectpath) == 0) {
		pstring s;
		pstrcpy(s,conn->connectpath);
		vfs_GetWd(conn,s);
		set_conn_connectpath(conn,s);
		vfs_ChDir(conn,conn->connectpath);
	}
#endif
	
	if (lp_unix_extensions() && lp_widelinks(snum)) {
		DEBUG(0,("Share '%s' has wide links and unix extensions enabled. "
			"These parameters are incompatible. "
			"Disabling wide links for this share.\n",
			lp_servicename(snum) ));
		lp_do_parameter(snum, "wide links", "False");
	}

	/*
	 * Print out the 'connected as' stuff here as we need
	 * to know the effective uid and gid we will be using
	 * (at least initially).
	 */

	if( DEBUGLVL( IS_IPC(conn) ? 3 : 1 ) ) {
		dbgtext( "%s (%s) ", get_remote_machine_name(),
			 conn->client_address );
		dbgtext( "%s", srv_is_signing_active() ? "signed " : "");
		dbgtext( "connect to service %s ", lp_servicename(snum) );
		dbgtext( "initially as user %s ", user );
		dbgtext( "(uid=%d, gid=%d) ", (int)geteuid(), (int)getegid() );
		dbgtext( "(pid %d)\n", (int)sys_getpid() );
	}
	
	/* we've finished with the user stuff - go back to root */
	change_to_root_user();
	return(conn);
}
Beispiel #6
0
static NTSTATUS create_conn_struct_as_root(TALLOC_CTX *ctx,
			    struct tevent_context *ev,
			    struct messaging_context *msg,
			    connection_struct **pconn,
			    int snum,
			    const char *path,
			    const struct auth_session_info *session_info)
{
	connection_struct *conn;
	char *connpath;
	const char *vfs_user;
	struct smbd_server_connection *sconn;
	const char *servicename = lp_const_servicename(snum);

	sconn = talloc_zero(ctx, struct smbd_server_connection);
	if (sconn == NULL) {
		return NT_STATUS_NO_MEMORY;
	}

	sconn->ev_ctx = ev;
	sconn->msg_ctx = msg;
	sconn->sock = -1;
	sconn->smb1.echo_handler.trusted_fd = -1;
	sconn->smb1.echo_handler.socket_lock_fd = -1;

	conn = conn_new(sconn);
	if (conn == NULL) {
		TALLOC_FREE(sconn);
		return NT_STATUS_NO_MEMORY;
	}

	/* Now we have conn, we need to make sconn a child of conn,
	 * for a proper talloc tree */
	talloc_steal(conn, sconn);

	if (snum == -1 && servicename == NULL) {
		servicename = "Unknown Service (snum == -1)";
	}

	connpath = talloc_strdup(conn, path);
	if (!connpath) {
		TALLOC_FREE(conn);
		return NT_STATUS_NO_MEMORY;
	}
	connpath = talloc_string_sub(conn,
				     connpath,
				     "%S",
				     servicename);
	if (!connpath) {
		TALLOC_FREE(conn);
		return NT_STATUS_NO_MEMORY;
	}

	/* needed for smbd_vfs_init() */

	conn->params->service = snum;
	conn->cnum = TID_FIELD_INVALID;

	if (session_info != NULL) {
		conn->session_info = copy_session_info(conn, session_info);
		if (conn->session_info == NULL) {
			DEBUG(0, ("copy_serverinfo failed\n"));
			TALLOC_FREE(conn);
			return NT_STATUS_NO_MEMORY;
		}
		vfs_user = conn->session_info->unix_info->unix_name;
	} else {
		/* use current authenticated user in absence of session_info */
		vfs_user = get_current_username();
	}

	set_conn_connectpath(conn, connpath);

	/*
	 * New code to check if there's a share security descripter
	 * added from NT server manager. This is done after the
	 * smb.conf checks are done as we need a uid and token. JRA.
	 *
	 */
	if (conn->session_info) {
		share_access_check(conn->session_info->security_token,
				   servicename,
				   MAXIMUM_ALLOWED_ACCESS,
				   &conn->share_access);

		if ((conn->share_access & FILE_WRITE_DATA) == 0) {
			if ((conn->share_access & FILE_READ_DATA) == 0) {
				/* No access, read or write. */
				DEBUG(0,("create_conn_struct: connection to %s "
					 "denied due to security "
					 "descriptor.\n",
					 servicename));
				conn_free(conn);
				return NT_STATUS_ACCESS_DENIED;
			} else {
				conn->read_only = true;
			}
		}
	} else {
		conn->share_access = 0;
		conn->read_only = true;
	}

	if (!smbd_vfs_init(conn)) {
		NTSTATUS status = map_nt_error_from_unix(errno);
		DEBUG(0,("create_conn_struct: smbd_vfs_init failed.\n"));
		conn_free(conn);
		return status;
	}

	/* this must be the first filesystem operation that we do */
	if (SMB_VFS_CONNECT(conn, servicename, vfs_user) < 0) {
		DEBUG(0,("VFS connect failed!\n"));
		conn_free(conn);
		return NT_STATUS_UNSUCCESSFUL;
	}

	conn->fs_capabilities = SMB_VFS_FS_CAPABILITIES(conn, &conn->ts_res);
	*pconn = conn;

	return NT_STATUS_OK;
}