Beispiel #1
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 #2
0
static bool check_user_ok(connection_struct *conn,
			uint64_t vuid,
			const struct auth_session_info *session_info,
			int snum)
{
	unsigned int i;
	bool readonly_share = false;
	bool admin_user = false;
	struct vuid_cache_entry *ent = NULL;
	uint32_t share_access = 0;
	NTSTATUS status;

	for (i=0; i<VUID_CACHE_SIZE; i++) {
		ent = &conn->vuid_cache->array[i];
		if (ent->vuid == vuid) {
			if (vuid == UID_FIELD_INVALID) {
				/*
				 * Slow path, we don't care
				 * about the array traversal.
				*/
				continue;
			}
			free_conn_session_info_if_unused(conn);
			conn->session_info = ent->session_info;
			conn->read_only = ent->read_only;
			conn->share_access = ent->share_access;
			return(True);
		}
	}

	status = check_user_share_access(conn,
					session_info,
					&share_access,
					&readonly_share);
	if (!NT_STATUS_IS_OK(status)) {
		return false;
	}

	admin_user = token_contains_name_in_list(
		session_info->unix_info->unix_name,
		session_info->info->domain_name,
		NULL, session_info->security_token, lp_admin_users(snum));

	ent = &conn->vuid_cache->array[conn->vuid_cache->next_entry];

	conn->vuid_cache->next_entry =
		(conn->vuid_cache->next_entry + 1) % VUID_CACHE_SIZE;

	TALLOC_FREE(ent->session_info);

	/*
	 * If force_user was set, all session_info's are based on the same
	 * username-based faked one.
	 */

	ent->session_info = copy_session_info(
		conn, conn->force_user ? conn->session_info : session_info);

	if (ent->session_info == NULL) {
		ent->vuid = UID_FIELD_INVALID;
		return false;
	}

	/*
	 * It's actually OK to call check_user_ok() with
	 * vuid == UID_FIELD_INVALID as called from change_to_user_by_session().
	 * All this will do is throw away one entry in the cache.
	 */

	ent->vuid = vuid;
	ent->read_only = readonly_share;
	ent->share_access = share_access;
	free_conn_session_info_if_unused(conn);
	conn->session_info = ent->session_info;
	if (vuid == UID_FIELD_INVALID) {
		/*
		 * Not strictly needed, just make it really
		 * clear this entry is actually an unused one.
		 */
		ent->read_only = false;
		ent->share_access = 0;
		ent->session_info = NULL;
	}

	conn->read_only = readonly_share;
	conn->share_access = share_access;

	if (admin_user) {
		DEBUG(2,("check_user_ok: user %s is an admin user. "
			"Setting uid as %d\n",
			conn->session_info->unix_info->unix_name,
			sec_initial_uid() ));
		conn->session_info->unix_token->uid = sec_initial_uid();
	}

	return(True);
}