linux/net/tipc/node.h
Tuong Lien 1ef6f7c939 tipc: add automatic session key exchange
With support from the master key option in the previous commit, it
becomes easy to make frequent updates/exchanges of session keys between
authenticated cluster nodes.
Basically, there are two situations where the key exchange will take in
place:

- When a new node joins the cluster (with the master key), it will need
  to get its peer's TX key, so that be able to decrypt further messages
  from that peer.

- When a new session key is generated (by either user manual setting or
  later automatic rekeying feature), the key will be distributed to all
  peer nodes in the cluster.

A key to be exchanged is encapsulated in the data part of a 'MSG_CRYPTO
/KEY_DISTR_MSG' TIPC v2 message, then xmit-ed as usual and encrypted by
using the master key before sending out. Upon receipt of the message it
will be decrypted in the same way as regular messages, then attached as
the sender's RX key in the receiver node.

In this way, the key exchange is reliable by the link layer, as well as
security, integrity and authenticity by the crypto layer.

Also, the forward security will be easily achieved by user changing the
master key actively but this should not be required very frequently.

The key exchange feature is independent on the presence of a master key
Note however that the master key still is needed for new nodes to be
able to join the cluster. It is also optional, and can be turned off/on
via the sysfs: 'net/tipc/key_exchange_enabled' [default 1: enabled].

Backward compatibility is guaranteed because for nodes that do not have
master key support, key exchange using master key ie. tx_key = 0 if any
will be shortly discarded at the message validation step. In other
words, the key exchange feature will be automatically disabled to those
nodes.

v2: fix the "implicit declaration of function 'tipc_crypto_key_flush'"
error in node.c. The function only exists when built with the TIPC
"CONFIG_TIPC_CRYPTO" option.

v3: use 'info->extack' for a message emitted due to netlink operations
instead (- David's comment).

Reported-by: kernel test robot <lkp@intel.com>
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-18 13:58:37 -07:00

132 lines
5.8 KiB
C

/*
* net/tipc/node.h: Include file for TIPC node management routines
*
* Copyright (c) 2000-2006, 2014-2016, Ericsson AB
* Copyright (c) 2005, 2010-2014, Wind River Systems
* 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_NODE_H
#define _TIPC_NODE_H
#include "addr.h"
#include "net.h"
#include "bearer.h"
#include "msg.h"
/* Optional capabilities supported by this code version
*/
enum {
TIPC_SYN_BIT = (1),
TIPC_BCAST_SYNCH = (1 << 1),
TIPC_BCAST_STATE_NACK = (1 << 2),
TIPC_BLOCK_FLOWCTL = (1 << 3),
TIPC_BCAST_RCAST = (1 << 4),
TIPC_NODE_ID128 = (1 << 5),
TIPC_LINK_PROTO_SEQNO = (1 << 6),
TIPC_MCAST_RBCTL = (1 << 7),
TIPC_GAP_ACK_BLOCK = (1 << 8),
TIPC_TUNNEL_ENHANCED = (1 << 9),
TIPC_NAGLE = (1 << 10),
TIPC_NAMED_BCAST = (1 << 11)
};
#define TIPC_NODE_CAPABILITIES (TIPC_SYN_BIT | \
TIPC_BCAST_SYNCH | \
TIPC_BCAST_STATE_NACK | \
TIPC_BCAST_RCAST | \
TIPC_BLOCK_FLOWCTL | \
TIPC_NODE_ID128 | \
TIPC_LINK_PROTO_SEQNO | \
TIPC_MCAST_RBCTL | \
TIPC_GAP_ACK_BLOCK | \
TIPC_TUNNEL_ENHANCED | \
TIPC_NAGLE | \
TIPC_NAMED_BCAST)
#define INVALID_BEARER_ID -1
void tipc_node_stop(struct net *net);
bool tipc_node_get_id(struct net *net, u32 addr, u8 *id);
u32 tipc_node_get_addr(struct tipc_node *node);
char *tipc_node_get_id_str(struct tipc_node *node);
void tipc_node_put(struct tipc_node *node);
void tipc_node_get(struct tipc_node *node);
struct tipc_node *tipc_node_create(struct net *net, u32 addr, u8 *peer_id,
u16 capabilities, u32 hash_mixes,
bool preliminary);
#ifdef CONFIG_TIPC_CRYPTO
struct tipc_crypto *tipc_node_crypto_rx(struct tipc_node *__n);
struct tipc_crypto *tipc_node_crypto_rx_by_list(struct list_head *pos);
struct tipc_crypto *tipc_node_crypto_rx_by_addr(struct net *net, u32 addr);
#endif
u32 tipc_node_try_addr(struct net *net, u8 *id, u32 addr);
void tipc_node_check_dest(struct net *net, u32 onode, u8 *peer_id128,
struct tipc_bearer *bearer,
u16 capabilities, u32 signature, u32 hash_mixes,
struct tipc_media_addr *maddr,
bool *respond, bool *dupl_addr);
void tipc_node_delete_links(struct net *net, int bearer_id);
void tipc_node_apply_property(struct net *net, struct tipc_bearer *b, int prop);
int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 node,
char *linkname, size_t len);
int tipc_node_xmit(struct net *net, struct sk_buff_head *list, u32 dnode,
int selector);
int tipc_node_distr_xmit(struct net *net, struct sk_buff_head *list);
int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dest,
u32 selector);
void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr);
void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr);
void tipc_node_broadcast(struct net *net, struct sk_buff *skb, int rc_dests);
int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port);
void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port);
int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel, bool connected);
bool tipc_node_is_up(struct net *net, u32 addr);
u16 tipc_node_get_capabilities(struct net *net, u32 addr);
int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb);
int tipc_nl_node_dump_link(struct sk_buff *skb, struct netlink_callback *cb);
int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info);
int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info);
int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info);
int tipc_nl_peer_rm(struct sk_buff *skb, struct genl_info *info);
int tipc_nl_node_set_monitor(struct sk_buff *skb, struct genl_info *info);
int tipc_nl_node_get_monitor(struct sk_buff *skb, struct genl_info *info);
int tipc_nl_node_dump_monitor(struct sk_buff *skb, struct netlink_callback *cb);
int tipc_nl_node_dump_monitor_peer(struct sk_buff *skb,
struct netlink_callback *cb);
#ifdef CONFIG_TIPC_CRYPTO
int tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info);
int tipc_nl_node_flush_key(struct sk_buff *skb, struct genl_info *info);
#endif
void tipc_node_pre_cleanup_net(struct net *exit_net);
#endif