alistair23-linux/net/tipc/addr.h
Jon Maloy 5f75e0a0e9 tipc: make node number calculation reproducible
The 32-bit node number, aka node hash or node address, is calculated
based on the 128-bit node identity when it is not set explicitly by
the user. In future commits we will need to perform this hash operation
on peer nodes while feeling safe that we obtain the same result.

We do this by interpreting the initial hash as a network byte order
number. Whenever we need to use the number locally on a node
we must therefore translate it to host byte order to obtain an
architecure independent result.

Furthermore, given the context where we use this number, we must not
allow it to be zero unless the node identity also is zero. Hence, in
the rare cases when the xor-ed hash value may end up as zero we replace
it with a fix number, knowing that the code anyway is capable of
handling hash collisions.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-27 17:34:01 -08:00

93 lines
3 KiB
C

/*
* net/tipc/addr.h: Include file for TIPC address utility routines
*
* Copyright (c) 2000-2006, 2018, Ericsson AB
* Copyright (c) 2004-2005, Wind River Systems
* Copyright (c) 2020, Red Hat Inc
* 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_ADDR_H
#define _TIPC_ADDR_H
#include <linux/types.h>
#include <linux/tipc.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>
#include "core.h"
static inline u32 tipc_own_addr(struct net *net)
{
return tipc_net(net)->node_addr;
}
static inline u8 *tipc_own_id(struct net *net)
{
struct tipc_net *tn = tipc_net(net);
if (!strlen(tn->node_id_string))
return NULL;
return tn->node_id;
}
static inline char *tipc_own_id_string(struct net *net)
{
return tipc_net(net)->node_id_string;
}
static inline u32 tipc_cluster_mask(u32 addr)
{
return addr & TIPC_ZONE_CLUSTER_MASK;
}
static inline int tipc_node2scope(u32 node)
{
return node ? TIPC_NODE_SCOPE : TIPC_CLUSTER_SCOPE;
}
static inline int tipc_scope2node(struct net *net, int sc)
{
return sc != TIPC_NODE_SCOPE ? 0 : tipc_own_addr(net);
}
static inline int in_own_node(struct net *net, u32 addr)
{
return addr == tipc_own_addr(net) || !addr;
}
bool tipc_in_scope(bool legacy_format, u32 domain, u32 addr);
void tipc_set_node_id(struct net *net, u8 *id);
void tipc_set_node_addr(struct net *net, u32 addr);
char *tipc_nodeid2string(char *str, u8 *id);
u32 tipc_node_id2hash(u8 *id128);
#endif