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 "link.h" 45#include "netlink.h" 46#include "monitor.h" 47 48/* 49 * The TIPC locking policy is designed to ensure a very fine locking 50 * granularity, permitting complete parallel access to individual 51 * port and node/link instances. The code consists of four major 52 * locking domains, each protected with their own disjunct set of locks. 53 * 54 * 1: The bearer level. 55 * RTNL lock is used to serialize the process of configuring bearer 56 * on update side, and RCU lock is applied on read side to make 57 * bearer instance valid on both paths of message transmission and 58 * reception. 59 * 60 * 2: The node and link level. 61 * All node instances are saved into two tipc_node_list and node_htable 62 * lists. The two lists are protected by node_list_lock on write side, 63 * and they are guarded with RCU lock on read side. Especially node 64 * instance is destroyed only when TIPC module is removed, and we can 65 * confirm that there has no any user who is accessing the node at the 66 * moment. Therefore, Except for iterating the two lists within RCU 67 * protection, it's no needed to hold RCU that we access node instance 68 * in other places. 69 * 70 * In addition, all members in node structure including link instances 71 * are protected by node spin lock. 72 * 73 * 3: The transport level of the protocol. 74 * This consists of the structures port, (and its user level 75 * representations, such as user_port and tipc_sock), reference and 76 * tipc_user (port.c, reg.c, socket.c). 77 * 78 * This layer has four different locks: 79 * - The tipc_port spin_lock. This is protecting each port instance 80 * from parallel data access and removal. Since we can not place 81 * this lock in the port itself, it has been placed in the 82 * corresponding reference table entry, which has the same life 83 * cycle as the module. This entry is difficult to access from 84 * outside the TIPC core, however, so a pointer to the lock has 85 * been added in the port instance, -to be used for unlocking 86 * only. 87 * - A read/write lock to protect the reference table itself (teg.c). 88 * (Nobody is using read-only access to this, so it can just as 89 * well be changed to a spin_lock) 90 * - A spin lock to protect the registry of kernel/driver users (reg.c) 91 * - A global spin_lock (tipc_port_lock), which only task is to ensure 92 * consistency where more than one port is involved in an operation, 93 * i.e., when a port is part of a linked list of ports. 94 * There are two such lists; 'port_list', which is used for management, 95 * and 'wait_list', which is used to queue ports during congestion. 96 * 97 * 4: The name table (name_table.c, name_distr.c, subscription.c) 98 * - There is one big read/write-lock (tipc_nametbl_lock) protecting the 99 * overall name table structure. Nothing must be added/removed to 100 * this structure without holding write access to it. 101 * - There is one local spin_lock per sub_sequence, which can be seen 102 * as a sub-domain to the tipc_nametbl_lock domain. It is used only 103 * for translation operations, and is needed because a translation 104 * steps the root of the 'publication' linked list between each lookup. 105 * This is always used within the scope of a tipc_nametbl_lock(read). 106 * - A local spin_lock protecting the queue of subscriber events. 107*/ 108 109static void tipc_net_finalize(struct net *net, u32 addr); 110 111int tipc_net_init(struct net *net, u8 *node_id, u32 addr) 112{ 113 if (tipc_own_id(net)) { 114 pr_info("Cannot configure node identity twice\n"); 115 return -1; 116 } 117 pr_info("Started in network mode\n"); 118 119 if (node_id) 120 tipc_set_node_id(net, node_id); 121 if (addr) 122 tipc_net_finalize(net, addr); 123 return 0; 124} 125 126static void tipc_net_finalize(struct net *net, u32 addr) 127{ 128 struct tipc_net *tn = tipc_net(net); 129 struct tipc_socket_addr sk = {0, addr}; 130 struct tipc_uaddr ua; 131 132 tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_CLUSTER_SCOPE, 133 TIPC_NODE_STATE, addr, addr); 134 135 if (cmpxchg(&tn->node_addr, 0, addr)) 136 return; 137 tipc_set_node_addr(net, addr); 138 tipc_named_reinit(net); 139 tipc_sk_reinit(net); 140 tipc_mon_reinit_self(net); 141 tipc_nametbl_publish(net, &ua, &sk, addr); 142} 143 144void tipc_net_finalize_work(struct work_struct *work) 145{ 146 struct tipc_net *tn = container_of(work, struct tipc_net, work); 147 148 tipc_net_finalize(tipc_link_net(tn->bcl), tn->trial_addr); 149} 150 151void tipc_net_stop(struct net *net) 152{ 153 if (!tipc_own_id(net)) 154 return; 155 156 rtnl_lock(); 157 tipc_bearer_stop(net); 158 tipc_node_stop(net); 159 rtnl_unlock(); 160 161 pr_info("Left network mode\n"); 162} 163 164static int __tipc_nl_add_net(struct net *net, struct tipc_nl_msg *msg) 165{ 166 struct tipc_net *tn = net_generic(net, tipc_net_id); 167 u64 *w0 = (u64 *)&tn->node_id[0]; 168 u64 *w1 = (u64 *)&tn->node_id[8]; 169 struct nlattr *attrs; 170 void *hdr; 171 172 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family, 173 NLM_F_MULTI, TIPC_NL_NET_GET); 174 if (!hdr) 175 return -EMSGSIZE; 176 177 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NET); 178 if (!attrs) 179 goto msg_full; 180 181 if (nla_put_u32(msg->skb, TIPC_NLA_NET_ID, tn->net_id)) 182 goto attr_msg_full; 183 if (nla_put_u64_64bit(msg->skb, TIPC_NLA_NET_NODEID, *w0, 0)) 184 goto attr_msg_full; 185 if (nla_put_u64_64bit(msg->skb, TIPC_NLA_NET_NODEID_W1, *w1, 0)) 186 goto attr_msg_full; 187 nla_nest_end(msg->skb, attrs); 188 genlmsg_end(msg->skb, hdr); 189 190 return 0; 191 192attr_msg_full: 193 nla_nest_cancel(msg->skb, attrs); 194msg_full: 195 genlmsg_cancel(msg->skb, hdr); 196 197 return -EMSGSIZE; 198} 199 200int tipc_nl_net_dump(struct sk_buff *skb, struct netlink_callback *cb) 201{ 202 struct net *net = sock_net(skb->sk); 203 int err; 204 int done = cb->args[0]; 205 struct tipc_nl_msg msg; 206 207 if (done) 208 return 0; 209 210 msg.skb = skb; 211 msg.portid = NETLINK_CB(cb->skb).portid; 212 msg.seq = cb->nlh->nlmsg_seq; 213 214 err = __tipc_nl_add_net(net, &msg); 215 if (err) 216 goto out; 217 218 done = 1; 219out: 220 cb->args[0] = done; 221 222 return skb->len; 223} 224 225int __tipc_nl_net_set(struct sk_buff *skb, struct genl_info *info) 226{ 227 struct nlattr *attrs[TIPC_NLA_NET_MAX + 1]; 228 struct net *net = sock_net(skb->sk); 229 struct tipc_net *tn = tipc_net(net); 230 int err; 231 232 if (!info->attrs[TIPC_NLA_NET]) 233 return -EINVAL; 234 235 err = nla_parse_nested_deprecated(attrs, TIPC_NLA_NET_MAX, 236 info->attrs[TIPC_NLA_NET], 237 tipc_nl_net_policy, info->extack); 238 239 if (err) 240 return err; 241 242 /* Can't change net id once TIPC has joined a network */ 243 if (tipc_own_addr(net)) 244 return -EPERM; 245 246 if (attrs[TIPC_NLA_NET_ID]) { 247 u32 val; 248 249 val = nla_get_u32(attrs[TIPC_NLA_NET_ID]); 250 if (val < 1 || val > 9999) 251 return -EINVAL; 252 253 tn->net_id = val; 254 } 255 256 if (attrs[TIPC_NLA_NET_ADDR]) { 257 u32 addr; 258 259 addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]); 260 if (!addr) 261 return -EINVAL; 262 tn->legacy_addr_format = true; 263 tipc_net_init(net, NULL, addr); 264 } 265 266 if (attrs[TIPC_NLA_NET_NODEID]) { 267 u8 node_id[NODE_ID_LEN]; 268 u64 *w0 = (u64 *)&node_id[0]; 269 u64 *w1 = (u64 *)&node_id[8]; 270 271 if (!attrs[TIPC_NLA_NET_NODEID_W1]) 272 return -EINVAL; 273 *w0 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID]); 274 *w1 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID_W1]); 275 tipc_net_init(net, node_id, 0); 276 } 277 return 0; 278} 279 280int tipc_nl_net_set(struct sk_buff *skb, struct genl_info *info) 281{ 282 int err; 283 284 rtnl_lock(); 285 err = __tipc_nl_net_set(skb, info); 286 rtnl_unlock(); 287 288 return err; 289} 290 291static int __tipc_nl_addr_legacy_get(struct net *net, struct tipc_nl_msg *msg) 292{ 293 struct tipc_net *tn = tipc_net(net); 294 struct nlattr *attrs; 295 void *hdr; 296 297 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family, 298 0, TIPC_NL_ADDR_LEGACY_GET); 299 if (!hdr) 300 return -EMSGSIZE; 301 302 attrs = nla_nest_start(msg->skb, TIPC_NLA_NET); 303 if (!attrs) 304 goto msg_full; 305 306 if (tn->legacy_addr_format) 307 if (nla_put_flag(msg->skb, TIPC_NLA_NET_ADDR_LEGACY)) 308 goto attr_msg_full; 309 310 nla_nest_end(msg->skb, attrs); 311 genlmsg_end(msg->skb, hdr); 312 313 return 0; 314 315attr_msg_full: 316 nla_nest_cancel(msg->skb, attrs); 317msg_full: 318 genlmsg_cancel(msg->skb, hdr); 319 320 return -EMSGSIZE; 321} 322 323int tipc_nl_net_addr_legacy_get(struct sk_buff *skb, struct genl_info *info) 324{ 325 struct net *net = sock_net(skb->sk); 326 struct tipc_nl_msg msg; 327 struct sk_buff *rep; 328 int err; 329 330 rep = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); 331 if (!rep) 332 return -ENOMEM; 333 334 msg.skb = rep; 335 msg.portid = info->snd_portid; 336 msg.seq = info->snd_seq; 337 338 err = __tipc_nl_addr_legacy_get(net, &msg); 339 if (err) { 340 nlmsg_free(msg.skb); 341 return err; 342 } 343 344 return genlmsg_reply(msg.skb, info); 345} 346