linux/net/tipc/core.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

233 lines
5.9 KiB
C

/*
* net/tipc/core.h: Include file for TIPC global declarations
*
* Copyright (c) 2005-2006, 2013-2018 Ericsson AB
* Copyright (c) 2005-2007, 2010-2013, 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_CORE_H
#define _TIPC_CORE_H
#include <linux/tipc.h>
#include <linux/tipc_config.h>
#include <linux/tipc_netlink.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/mm.h>
#include <linux/timer.h>
#include <linux/string.h>
#include <linux/uaccess.h>
#include <linux/interrupt.h>
#include <linux/atomic.h>
#include <linux/netdevice.h>
#include <linux/in.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/rtnetlink.h>
#include <linux/etherdevice.h>
#include <net/netns/generic.h>
#include <linux/rhashtable.h>
#include <net/genetlink.h>
#include <net/netns/hash.h>
#ifdef pr_fmt
#undef pr_fmt
#endif
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
struct tipc_node;
struct tipc_bearer;
struct tipc_bc_base;
struct tipc_link;
struct tipc_name_table;
struct tipc_topsrv;
struct tipc_monitor;
#ifdef CONFIG_TIPC_CRYPTO
struct tipc_crypto;
#endif
#define TIPC_MOD_VER "2.0.0"
#define NODE_HTABLE_SIZE 512
#define MAX_BEARERS 3
#define TIPC_DEF_MON_THRESHOLD 32
#define NODE_ID_LEN 16
#define NODE_ID_STR_LEN (NODE_ID_LEN * 2 + 1)
extern unsigned int tipc_net_id __read_mostly;
extern int sysctl_tipc_rmem[3] __read_mostly;
extern int sysctl_tipc_named_timeout __read_mostly;
struct tipc_net_work {
struct work_struct work;
struct net *net;
u32 addr;
};
struct tipc_net {
u8 node_id[NODE_ID_LEN];
u32 node_addr;
u32 trial_addr;
unsigned long addr_trial_end;
char node_id_string[NODE_ID_STR_LEN];
int net_id;
int random;
bool legacy_addr_format;
/* Node table and node list */
spinlock_t node_list_lock;
struct hlist_head node_htable[NODE_HTABLE_SIZE];
struct list_head node_list;
u32 num_nodes;
u32 num_links;
/* Neighbor monitoring list */
struct tipc_monitor *monitors[MAX_BEARERS];
int mon_threshold;
/* Bearer list */
struct tipc_bearer __rcu *bearer_list[MAX_BEARERS + 1];
/* Broadcast link */
spinlock_t bclock;
struct tipc_bc_base *bcbase;
struct tipc_link *bcl;
/* Socket hash table */
struct rhashtable sk_rht;
/* Name table */
spinlock_t nametbl_lock;
struct name_table *nametbl;
/* Topology subscription server */
struct tipc_topsrv *topsrv;
atomic_t subscription_count;
/* Cluster capabilities */
u16 capabilities;
/* Tracing of node internal messages */
struct packet_type loopback_pt;
#ifdef CONFIG_TIPC_CRYPTO
/* TX crypto handler */
struct tipc_crypto *crypto_tx;
#endif
/* Work item for net finalize */
struct tipc_net_work final_work;
};
static inline struct tipc_net *tipc_net(struct net *net)
{
return net_generic(net, tipc_net_id);
}
static inline int tipc_netid(struct net *net)
{
return tipc_net(net)->net_id;
}
static inline struct list_head *tipc_nodes(struct net *net)
{
return &tipc_net(net)->node_list;
}
static inline struct name_table *tipc_name_table(struct net *net)
{
return tipc_net(net)->nametbl;
}
static inline struct tipc_topsrv *tipc_topsrv(struct net *net)
{
return tipc_net(net)->topsrv;
}
static inline unsigned int tipc_hashfn(u32 addr)
{
return addr & (NODE_HTABLE_SIZE - 1);
}
static inline u16 mod(u16 x)
{
return x & 0xffffu;
}
static inline int less_eq(u16 left, u16 right)
{
return mod(right - left) < 32768u;
}
static inline int more(u16 left, u16 right)
{
return !less_eq(left, right);
}
static inline int less(u16 left, u16 right)
{
return less_eq(left, right) && (mod(right) != mod(left));
}
static inline int in_range(u16 val, u16 min, u16 max)
{
return !less(val, min) && !more(val, max);
}
static inline u32 tipc_net_hash_mixes(struct net *net, int tn_rand)
{
return net_hash_mix(&init_net) ^ net_hash_mix(net) ^ tn_rand;
}
static inline u32 hash128to32(char *bytes)
{
__be32 *tmp = (__be32 *)bytes;
u32 res;
res = ntohl(tmp[0] ^ tmp[1] ^ tmp[2] ^ tmp[3]);
if (likely(res))
return res;
return ntohl(tmp[0] | tmp[1] | tmp[2] | tmp[3]);
}
#ifdef CONFIG_SYSCTL
int tipc_register_sysctl(void);
void tipc_unregister_sysctl(void);
#else
#define tipc_register_sysctl() 0
#define tipc_unregister_sysctl()
#endif
#endif