/* * net/tipc/net.c: TIPC network routing code * * Copyright (c) 1995-2006, 2014, Ericsson AB * Copyright (c) 2005, 2010-2011, 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. */ #include "core.h"#include "net.h"#include "name_distr.h"#include "subscr.h"#include "socket.h"#include "node.h"#include "bcast.h"#include "link.h"#include "netlink.h"#include "monitor.h" /* * The TIPC locking policy is designed to ensure a very fine locking * granularity, permitting complete parallel access to individual * port and node/link instances. The code consists of four major * locking domains, each protected with their own disjunct set of locks. * * 1: The bearer level. *    RTNL lock is used to serialize the process of configuring bearer *    on update side, and RCU lock is applied on read side to make *    bearer instance valid on both paths of message transmission and *    reception. * * 2: The node and link level. *    All node instances are saved into two tipc_node_list and node_htable *    lists. The two lists are protected by node_list_lock on write side, *    and they are guarded with RCU lock on read side. Especially node *    instance is destroyed only when TIPC module is removed, and we can *    confirm that there has no any user who is accessing the node at the *    moment. Therefore, Except for iterating the two lists within RCU *    protection, it's no needed to hold RCU that we access node instance *    in other places. * *    In addition, all members in node structure including link instances *    are protected by node spin lock. * * 3: The transport level of the protocol. *    This consists of the structures port, (and its user level *    representations, such as user_port and tipc_sock), reference and *    tipc_user (port.c, reg.c, socket.c). * *    This layer has four different locks: *     - The tipc_port spin_lock. This is protecting each port instance *       from parallel data access and removal. Since we can not place *       this lock in the port itself, it has been placed in the *       corresponding reference table entry, which has the same life *       cycle as the module. This entry is difficult to access from *       outside the TIPC core, however, so a pointer to the lock has *       been added in the port instance, -to be used for unlocking *       only. *     - A read/write lock to protect the reference table itself (teg.c). *       (Nobody is using read-only access to this, so it can just as *       well be changed to a spin_lock) *     - A spin lock to protect the registry of kernel/driver users (reg.c) *     - A global spin_lock (tipc_port_lock), which only task is to ensure *       consistency where more than one port is involved in an operation, *       i.e., when a port is part of a linked list of ports. *       There are two such lists; 'port_list', which is used for management, *       and 'wait_list', which is used to queue ports during congestion. * *  4: The name table (name_table.c, name_distr.c, subscription.c) *     - There is one big read/write-lock (tipc_nametbl_lock) protecting the *       overall name table structure. Nothing must be added/removed to *       this structure without holding write access to it. *     - There is one local spin_lock per sub_sequence, which can be seen *       as a sub-domain to the tipc_nametbl_lock domain. It is used only *       for translation operations, and is needed because a translation *       steps the root of the 'publication' linked list between each lookup. *       This is always used within the scope of a tipc_nametbl_lock(read). *     - A local spin_lock protecting the queue of subscriber events.*/ static void tipc_net_finalize(struct net *net, u32 addr); int tipc_net_init(struct net *net, u8 *node_id, u32 addr){	if (tipc_own_id(net)) {		pr_info("Cannot configure node identity twice\n");		return -1;	}	pr_info("Started in network mode\n"); 	if (node_id)		tipc_set_node_id(net, node_id);	if (addr)		tipc_net_finalize(net, addr);	return 0;} static void tipc_net_finalize(struct net *net, u32 addr){	struct tipc_net *tn = tipc_net(net);	struct tipc_socket_addr sk = {0, addr};	struct tipc_uaddr ua; 	tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_CLUSTER_SCOPE,		   TIPC_NODE_STATE, addr, addr); 	if (cmpxchg(&tn->node_addr, 0, addr))		return;	tipc_set_node_addr(net, addr);	tipc_named_reinit(net);	tipc_sk_reinit(net);	tipc_mon_reinit_self(net);	tipc_nametbl_publish(net, &ua, &sk, addr);} void tipc_net_finalize_work(struct work_struct *work){	struct tipc_net *tn = container_of(work, struct tipc_net, work); 	rtnl_lock();	tipc_net_finalize(tipc_link_net(tn->bcl), tn->trial_addr);	rtnl_unlock();} void tipc_net_stop(struct net *net){	if (!tipc_own_id(net))		return; 	rtnl_lock();	tipc_bearer_stop(net);	tipc_node_stop(net);	rtnl_unlock(); 	pr_info("Left network mode\n");} static int __tipc_nl_add_net(struct net *net, struct tipc_nl_msg *msg){	struct tipc_net *tn = net_generic(net, tipc_net_id);	u64 *w0 = (u64 *)&tn->node_id[0];	u64 *w1 = (u64 *)&tn->node_id[8];	struct nlattr *attrs;	void *hdr; 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,			  NLM_F_MULTI, TIPC_NL_NET_GET);	if (!hdr)		return -EMSGSIZE; 	attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NET);	if (!attrs)		goto msg_full; 	if (nla_put_u32(msg->skb, TIPC_NLA_NET_ID, tn->net_id))		goto attr_msg_full;	if (nla_put_u64_64bit(msg->skb, TIPC_NLA_NET_NODEID, *w0, 0))		goto attr_msg_full;	if (nla_put_u64_64bit(msg->skb, TIPC_NLA_NET_NODEID_W1, *w1, 0))		goto attr_msg_full;	nla_nest_end(msg->skb, attrs);	genlmsg_end(msg->skb, hdr); 	return 0; attr_msg_full:	nla_nest_cancel(msg->skb, attrs);msg_full:	genlmsg_cancel(msg->skb, hdr); 	return -EMSGSIZE;} int tipc_nl_net_dump(struct sk_buff *skb, struct netlink_callback *cb){	struct net *net = sock_net(skb->sk);	int err;	int done = cb->args[0];	struct tipc_nl_msg msg; 	if (done)		return 0; 	msg.skb = skb;	msg.portid = NETLINK_CB(cb->skb).portid;	msg.seq = cb->nlh->nlmsg_seq; 	err = __tipc_nl_add_net(net, &msg);	if (err)		goto out; 	done = 1;out:	cb->args[0] = done; 	return skb->len;} int __tipc_nl_net_set(struct sk_buff *skb, struct genl_info *info){	struct nlattr *attrs[TIPC_NLA_NET_MAX + 1];	struct net *net = sock_net(skb->sk);	struct tipc_net *tn = tipc_net(net);	int err; 	if (!info->attrs[TIPC_NLA_NET])		return -EINVAL; 	err = nla_parse_nested_deprecated(attrs, TIPC_NLA_NET_MAX,					  info->attrs[TIPC_NLA_NET],					  tipc_nl_net_policy, info->extack); 	if (err)		return err; 	/* Can't change net id once TIPC has joined a network */	if (tipc_own_addr(net))		return -EPERM; 	if (attrs[TIPC_NLA_NET_ID]) {		u32 val; 		val = nla_get_u32(attrs[TIPC_NLA_NET_ID]);		if (val < 1 || val > 9999)			return -EINVAL; 		tn->net_id = val;	} 	if (attrs[TIPC_NLA_NET_ADDR]) {		u32 addr; 		addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);		if (!addr)			return -EINVAL;		tn->legacy_addr_format = true;		tipc_net_init(net, NULL, addr);	} 	if (attrs[TIPC_NLA_NET_NODEID]) {		u8 node_id[NODE_ID_LEN];		u64 *w0 = (u64 *)&node_id[0];		u64 *w1 = (u64 *)&node_id[8]; 		if (!attrs[TIPC_NLA_NET_NODEID_W1])			return -EINVAL;		*w0 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID]);		*w1 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID_W1]);		tipc_net_init(net, node_id, 0);	}	return 0;} int tipc_nl_net_set(struct sk_buff *skb, struct genl_info *info){	int err; 	rtnl_lock();	err = __tipc_nl_net_set(skb, info);	rtnl_unlock(); 	return err;} static int __tipc_nl_addr_legacy_get(struct net *net, struct tipc_nl_msg *msg){	struct tipc_net *tn = tipc_net(net);	struct nlattr *attrs;	void *hdr; 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,			  0, TIPC_NL_ADDR_LEGACY_GET);	if (!hdr)		return -EMSGSIZE; 	attrs = nla_nest_start(msg->skb, TIPC_NLA_NET);	if (!attrs)		goto msg_full; 	if (tn->legacy_addr_format)		if (nla_put_flag(msg->skb, TIPC_NLA_NET_ADDR_LEGACY))			goto attr_msg_full; 	nla_nest_end(msg->skb, attrs);	genlmsg_end(msg->skb, hdr); 	return 0; attr_msg_full:	nla_nest_cancel(msg->skb, attrs);msg_full:	genlmsg_cancel(msg->skb, hdr); 	return -EMSGSIZE;} int tipc_nl_net_addr_legacy_get(struct sk_buff *skb, struct genl_info *info){	struct net *net = sock_net(skb->sk);	struct tipc_nl_msg msg;	struct sk_buff *rep;	int err; 	rep = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);	if (!rep)		return -ENOMEM; 	msg.skb = rep;	msg.portid = info->snd_portid;	msg.seq = info->snd_seq; 	err = __tipc_nl_addr_legacy_get(net, &msg);	if (err) {		nlmsg_free(msg.skb);		return err;	} 	return genlmsg_reply(msg.skb, info);}