1 /*
2 * net/tipc/net.c: TIPC network routing code
3 *
4 * Copyright (c) 1995-2006, 2014, Ericsson AB
5 * Copyright (c) 2005, 2010-2011, Wind River Systems
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
19 *
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
35 */
36
37 #include "core.h"
38 #include "net.h"
39 #include "name_distr.h"
40 #include "subscr.h"
41 #include "socket.h"
42 #include "node.h"
43 #include "bcast.h"
44 #include "netlink.h"
45 #include "monitor.h"
46
47 /*
48 * The TIPC locking policy is designed to ensure a very fine locking
49 * granularity, permitting complete parallel access to individual
50 * port and node/link instances. The code consists of four major
51 * locking domains, each protected with their own disjunct set of locks.
52 *
53 * 1: The bearer level.
54 * RTNL lock is used to serialize the process of configuring bearer
55 * on update side, and RCU lock is applied on read side to make
56 * bearer instance valid on both paths of message transmission and
57 * reception.
58 *
59 * 2: The node and link level.
60 * All node instances are saved into two tipc_node_list and node_htable
61 * lists. The two lists are protected by node_list_lock on write side,
62 * and they are guarded with RCU lock on read side. Especially node
63 * instance is destroyed only when TIPC module is removed, and we can
64 * confirm that there has no any user who is accessing the node at the
65 * moment. Therefore, Except for iterating the two lists within RCU
66 * protection, it's no needed to hold RCU that we access node instance
67 * in other places.
68 *
69 * In addition, all members in node structure including link instances
70 * are protected by node spin lock.
71 *
72 * 3: The transport level of the protocol.
73 * This consists of the structures port, (and its user level
74 * representations, such as user_port and tipc_sock), reference and
75 * tipc_user (port.c, reg.c, socket.c).
76 *
77 * This layer has four different locks:
78 * - The tipc_port spin_lock. This is protecting each port instance
79 * from parallel data access and removal. Since we can not place
80 * this lock in the port itself, it has been placed in the
81 * corresponding reference table entry, which has the same life
82 * cycle as the module. This entry is difficult to access from
83 * outside the TIPC core, however, so a pointer to the lock has
84 * been added in the port instance, -to be used for unlocking
85 * only.
86 * - A read/write lock to protect the reference table itself (teg.c).
87 * (Nobody is using read-only access to this, so it can just as
88 * well be changed to a spin_lock)
89 * - A spin lock to protect the registry of kernel/driver users (reg.c)
90 * - A global spin_lock (tipc_port_lock), which only task is to ensure
91 * consistency where more than one port is involved in an operation,
92 * i.e., whe a port is part of a linked list of ports.
93 * There are two such lists; 'port_list', which is used for management,
94 * and 'wait_list', which is used to queue ports during congestion.
95 *
96 * 4: The name table (name_table.c, name_distr.c, subscription.c)
97 * - There is one big read/write-lock (tipc_nametbl_lock) protecting the
98 * overall name table structure. Nothing must be added/removed to
99 * this structure without holding write access to it.
100 * - There is one local spin_lock per sub_sequence, which can be seen
101 * as a sub-domain to the tipc_nametbl_lock domain. It is used only
102 * for translation operations, and is needed because a translation
103 * steps the root of the 'publication' linked list between each lookup.
104 * This is always used within the scope of a tipc_nametbl_lock(read).
105 * - A local spin_lock protecting the queue of subscriber events.
106 */
107
108 static void tipc_net_finalize(struct net *net, u32 addr);
109
tipc_net_init(struct net * net,u8 * node_id,u32 addr)110 int tipc_net_init(struct net *net, u8 *node_id, u32 addr)
111 {
112 if (tipc_own_id(net)) {
113 pr_info("Cannot configure node identity twice\n");
114 return -1;
115 }
116 pr_info("Started in network mode\n");
117
118 if (node_id)
119 tipc_set_node_id(net, node_id);
120 if (addr)
121 tipc_net_finalize(net, addr);
122 return 0;
123 }
124
tipc_net_finalize(struct net * net,u32 addr)125 static void tipc_net_finalize(struct net *net, u32 addr)
126 {
127 struct tipc_net *tn = tipc_net(net);
128
129 if (cmpxchg(&tn->node_addr, 0, addr))
130 return;
131 tipc_set_node_addr(net, addr);
132 tipc_named_reinit(net);
133 tipc_sk_reinit(net);
134 tipc_mon_reinit_self(net);
135 tipc_nametbl_publish(net, TIPC_CFG_SRV, addr, addr,
136 TIPC_CLUSTER_SCOPE, 0, addr);
137 }
138
tipc_net_finalize_work(struct work_struct * work)139 void tipc_net_finalize_work(struct work_struct *work)
140 {
141 struct tipc_net_work *fwork;
142
143 fwork = container_of(work, struct tipc_net_work, work);
144 tipc_net_finalize(fwork->net, fwork->addr);
145 }
146
tipc_sched_net_finalize(struct net * net,u32 addr)147 void tipc_sched_net_finalize(struct net *net, u32 addr)
148 {
149 struct tipc_net *tn = tipc_net(net);
150
151 tn->final_work.net = net;
152 tn->final_work.addr = addr;
153 schedule_work(&tn->final_work.work);
154 }
155
tipc_net_stop(struct net * net)156 void tipc_net_stop(struct net *net)
157 {
158 if (!tipc_own_id(net))
159 return;
160
161 rtnl_lock();
162 tipc_bearer_stop(net);
163 tipc_node_stop(net);
164 rtnl_unlock();
165
166 pr_info("Left network mode\n");
167 }
168
__tipc_nl_add_net(struct net * net,struct tipc_nl_msg * msg)169 static int __tipc_nl_add_net(struct net *net, struct tipc_nl_msg *msg)
170 {
171 struct tipc_net *tn = net_generic(net, tipc_net_id);
172 u64 *w0 = (u64 *)&tn->node_id[0];
173 u64 *w1 = (u64 *)&tn->node_id[8];
174 struct nlattr *attrs;
175 void *hdr;
176
177 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
178 NLM_F_MULTI, TIPC_NL_NET_GET);
179 if (!hdr)
180 return -EMSGSIZE;
181
182 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NET);
183 if (!attrs)
184 goto msg_full;
185
186 if (nla_put_u32(msg->skb, TIPC_NLA_NET_ID, tn->net_id))
187 goto attr_msg_full;
188 if (nla_put_u64_64bit(msg->skb, TIPC_NLA_NET_NODEID, *w0, 0))
189 goto attr_msg_full;
190 if (nla_put_u64_64bit(msg->skb, TIPC_NLA_NET_NODEID_W1, *w1, 0))
191 goto attr_msg_full;
192 nla_nest_end(msg->skb, attrs);
193 genlmsg_end(msg->skb, hdr);
194
195 return 0;
196
197 attr_msg_full:
198 nla_nest_cancel(msg->skb, attrs);
199 msg_full:
200 genlmsg_cancel(msg->skb, hdr);
201
202 return -EMSGSIZE;
203 }
204
tipc_nl_net_dump(struct sk_buff * skb,struct netlink_callback * cb)205 int tipc_nl_net_dump(struct sk_buff *skb, struct netlink_callback *cb)
206 {
207 struct net *net = sock_net(skb->sk);
208 int err;
209 int done = cb->args[0];
210 struct tipc_nl_msg msg;
211
212 if (done)
213 return 0;
214
215 msg.skb = skb;
216 msg.portid = NETLINK_CB(cb->skb).portid;
217 msg.seq = cb->nlh->nlmsg_seq;
218
219 err = __tipc_nl_add_net(net, &msg);
220 if (err)
221 goto out;
222
223 done = 1;
224 out:
225 cb->args[0] = done;
226
227 return skb->len;
228 }
229
__tipc_nl_net_set(struct sk_buff * skb,struct genl_info * info)230 int __tipc_nl_net_set(struct sk_buff *skb, struct genl_info *info)
231 {
232 struct nlattr *attrs[TIPC_NLA_NET_MAX + 1];
233 struct net *net = sock_net(skb->sk);
234 struct tipc_net *tn = tipc_net(net);
235 int err;
236
237 if (!info->attrs[TIPC_NLA_NET])
238 return -EINVAL;
239
240 err = nla_parse_nested_deprecated(attrs, TIPC_NLA_NET_MAX,
241 info->attrs[TIPC_NLA_NET],
242 tipc_nl_net_policy, info->extack);
243
244 if (err)
245 return err;
246
247 /* Can't change net id once TIPC has joined a network */
248 if (tipc_own_addr(net))
249 return -EPERM;
250
251 if (attrs[TIPC_NLA_NET_ID]) {
252 u32 val;
253
254 val = nla_get_u32(attrs[TIPC_NLA_NET_ID]);
255 if (val < 1 || val > 9999)
256 return -EINVAL;
257
258 tn->net_id = val;
259 }
260
261 if (attrs[TIPC_NLA_NET_ADDR]) {
262 u32 addr;
263
264 addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);
265 if (!addr)
266 return -EINVAL;
267 tn->legacy_addr_format = true;
268 tipc_net_init(net, NULL, addr);
269 }
270
271 if (attrs[TIPC_NLA_NET_NODEID]) {
272 u8 node_id[NODE_ID_LEN];
273 u64 *w0 = (u64 *)&node_id[0];
274 u64 *w1 = (u64 *)&node_id[8];
275
276 if (!attrs[TIPC_NLA_NET_NODEID_W1])
277 return -EINVAL;
278 *w0 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID]);
279 *w1 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID_W1]);
280 tipc_net_init(net, node_id, 0);
281 }
282 return 0;
283 }
284
tipc_nl_net_set(struct sk_buff * skb,struct genl_info * info)285 int tipc_nl_net_set(struct sk_buff *skb, struct genl_info *info)
286 {
287 int err;
288
289 rtnl_lock();
290 err = __tipc_nl_net_set(skb, info);
291 rtnl_unlock();
292
293 return err;
294 }
295