linux/net/tipc/core.h
Hoang Le f73b12812a tipc: improve throughput between nodes in netns
Currently, TIPC transports intra-node user data messages directly
socket to socket, hence shortcutting all the lower layers of the
communication stack. This gives TIPC very good intra node performance,
both regarding throughput and latency.

We now introduce a similar mechanism for TIPC data traffic across
network namespaces located in the same kernel. On the send path, the
call chain is as always accompanied by the sending node's network name
space pointer. However, once we have reliably established that the
receiving node is represented by a namespace on the same host, we just
replace the namespace pointer with the receiving node/namespace's
ditto, and follow the regular socket receive patch though the receiving
node. This technique gives us a throughput similar to the node internal
throughput, several times larger than if we let the traffic go though
the full network stacks. As a comparison, max throughput for 64k
messages is four times larger than TCP throughput for the same type of
traffic.

To meet any security concerns, the following should be noted.

- All nodes joining a cluster are supposed to have been be certified
and authenticated by mechanisms outside TIPC. This is no different for
nodes/namespaces on the same host; they have to auto discover each
other using the attached interfaces, and establish links which are
supervised via the regular link monitoring mechanism. Hence, a kernel
local node has no other way to join a cluster than any other node, and
have to obey to policies set in the IP or device layers of the stack.

- Only when a sender has established with 100% certainty that the peer
node is located in a kernel local namespace does it choose to let user
data messages, and only those, take the crossover path to the receiving
node/namespace.

- If the receiving node/namespace is removed, its namespace pointer
is invalidated at all peer nodes, and their neighbor link monitoring
will eventually note that this node is gone.

- To ensure the "100% certainty" criteria, and prevent any possible
spoofing, received discovery messages must contain a proof that the
sender knows a common secret. We use the hash mix of the sending
node/namespace for this purpose, since it can be accessed directly by
all other namespaces in the kernel. Upon reception of a discovery
message, the receiver checks this proof against all the local
namespaces'hash_mix:es. If it finds a match, that, along with a
matching node id and cluster id, this is deemed sufficient proof that
the peer node in question is in a local namespace, and a wormhole can
be opened.

- We should also consider that TIPC is intended to be a cluster local
IPC mechanism (just like e.g. UNIX sockets) rather than a network
protocol, and hence we think it can justified to allow it to shortcut the
lower protocol layers.

Regarding traceability, we should notice that since commit 6c9081a391
("tipc: add loopback device tracking") it is possible to follow the node
internal packet flow by just activating tcpdump on the loopback
interface. This will be true even for this mechanism; by activating
tcpdump on the involved nodes' loopback interfaces their inter-name
space messaging can easily be tracked.

v2:
- update 'net' pointer when node left/rejoined
v3:
- grab read/write lock when using node ref obj
v4:
- clone traffics between netns to loopback

Suggested-by: Jon Maloy <jon.maloy@ericsson.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-29 17:55:38 -07:00

202 lines
5.3 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
* 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>
struct tipc_node;
struct tipc_bearer;
struct tipc_bc_base;
struct tipc_link;
struct tipc_name_table;
struct tipc_topsrv;
struct tipc_monitor;
#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 {
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;
/* Name dist queue */
struct list_head dist_queue;
/* 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;
};
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;
}
#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