linux/net/tipc/socket.h
Jon Maloy 72671b355f tipc: add stricter control of reserved service types
TIPC reserves 64 service types for current and future internal use.
Therefore, the bind() function is meant to block regular user sockets
from being bound to these values, while it should let through such
bindings from internal users.

However, since we at the design moment saw no way to distinguish
between regular and internal users the filter function ended up
with allowing all bindings of the reserved types which were really
in use ([0,1]), and block all the rest ([2,63]).

This is risky, since a regular user may bind to the service type
representing the topology server (TIPC_TOP_SRV == 1) or the one used
for indicating neighboring node status (TIPC_CFG_SRV == 0), and wreak
havoc for users of those services, i.e., most users.

The reality is however that TIPC_CFG_SRV never is bound through the
bind() function, since it doesn't represent a regular socket, and
TIPC_TOP_SRV can also be made to bypass the checks in tipc_bind()
by introducing a different entry function, tipc_sk_bind().

It should be noted that although this is a change of the API semantics,
there is no risk we will break any currently working applications by
doing this. Any application trying to bind to the values in question
would be badly broken from the outset, so there is no chance we would
find any such applications in real-world production systems.

v2: Added warning printout when a user is blocked from binding,
    as suggested by Jakub Kicinski

Acked-by: Yung Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jmaloy@redhat.com>
Link: https://lore.kernel.org/r/20201030012938.489557-1-jmaloy@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-30 08:19:18 -07:00

81 lines
3.6 KiB
C

/* net/tipc/socket.h: Include file for TIPC socket code
*
* Copyright (c) 2014-2016, Ericsson AB
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the names of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _TIPC_SOCK_H
#define _TIPC_SOCK_H
#include <net/sock.h>
#include <net/genetlink.h>
/* Compatibility values for deprecated message based flow control */
#define FLOWCTL_MSG_WIN 512
#define FLOWCTL_MSG_LIM ((FLOWCTL_MSG_WIN * 2 + 1) * SKB_TRUESIZE(MAX_MSG_SIZE))
#define FLOWCTL_BLK_SZ 1024
/* Socket receive buffer sizes */
#define RCVBUF_MIN (FLOWCTL_BLK_SZ * 512)
#define RCVBUF_DEF (FLOWCTL_BLK_SZ * 1024 * 2)
#define RCVBUF_MAX (FLOWCTL_BLK_SZ * 1024 * 16)
struct tipc_sock;
int tipc_socket_init(void);
void tipc_socket_stop(void);
void tipc_sk_rcv(struct net *net, struct sk_buff_head *inputq);
void tipc_sk_mcast_rcv(struct net *net, struct sk_buff_head *arrvq,
struct sk_buff_head *inputq);
void tipc_sk_reinit(struct net *net);
int tipc_sk_rht_init(struct net *net);
void tipc_sk_rht_destroy(struct net *net);
int tipc_nl_sk_dump(struct sk_buff *skb, struct netlink_callback *cb);
int tipc_nl_publ_dump(struct sk_buff *skb, struct netlink_callback *cb);
int tipc_sk_fill_sock_diag(struct sk_buff *skb, struct netlink_callback *cb,
struct tipc_sock *tsk, u32 sk_filter_state,
u64 (*tipc_diag_gen_cookie)(struct sock *sk));
int tipc_nl_sk_walk(struct sk_buff *skb, struct netlink_callback *cb,
int (*skb_handler)(struct sk_buff *skb,
struct netlink_callback *cb,
struct tipc_sock *tsk));
int tipc_dump_start(struct netlink_callback *cb);
int __tipc_dump_start(struct netlink_callback *cb, struct net *net);
int tipc_dump_done(struct netlink_callback *cb);
u32 tipc_sock_get_portid(struct sock *sk);
bool tipc_sk_overlimit1(struct sock *sk, struct sk_buff *skb);
bool tipc_sk_overlimit2(struct sock *sk, struct sk_buff *skb);
int tipc_sk_bind(struct socket *sock, struct sockaddr *skaddr, int alen);
int tsk_set_importance(struct sock *sk, int imp);
#endif