net/tipc/node.c

0001 /*
0002  * net/tipc/node.c: TIPC node management routines
0003  *
0004  * Copyright (c) 2000-2006, 2012-2016, Ericsson AB
0005  * Copyright (c) 2005-2006, 2010-2014, Wind River Systems
0006  * All rights reserved.
0007  *
0008  * Redistribution and use in source and binary forms, with or without
0009  * modification, are permitted provided that the following conditions are met:
0010  *
0011  * 1. Redistributions of source code must retain the above copyright
0012  *    notice, this list of conditions and the following disclaimer.
0013  * 2. Redistributions in binary form must reproduce the above copyright
0014  *    notice, this list of conditions and the following disclaimer in the
0015  *    documentation and/or other materials provided with the distribution.
0016  * 3. Neither the names of the copyright holders nor the names of its
0017  *    contributors may be used to endorse or promote products derived from
0018  *    this software without specific prior written permission.
0019  *
0020  * Alternatively, this software may be distributed under the terms of the
0021  * GNU General Public License ("GPL") version 2 as published by the Free
0022  * Software Foundation.
0023  *
0024  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0025  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0026  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0027  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0028  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0029  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0030  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0031  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0032  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0033  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0034  * POSSIBILITY OF SUCH DAMAGE.
0035  */
0036
0037 #include "core.h"
0038 #include "link.h"
0039 #include "node.h"
0040 #include "name_distr.h"
0041 #include "socket.h"
0042 #include "bcast.h"
0043 #include "monitor.h"
0044 #include "discover.h"
0045 #include "netlink.h"
0046 #include "trace.h"
0047 #include "crypto.h"
0048
0049 #define INVALID_NODE_SIG    0x10000
0050 #define NODE_CLEANUP_AFTER  300000
0051
0052 /* Flags used to take different actions according to flag type
0053  * TIPC_NOTIFY_NODE_DOWN: notify node is down
0054  * TIPC_NOTIFY_NODE_UP: notify node is up
0055  * TIPC_DISTRIBUTE_NAME: publish or withdraw link state name type
0056  */
0057 enum {
0058     TIPC_NOTIFY_NODE_DOWN       = (1 << 3),
0059     TIPC_NOTIFY_NODE_UP     = (1 << 4),
0060     TIPC_NOTIFY_LINK_UP     = (1 << 6),
0061     TIPC_NOTIFY_LINK_DOWN       = (1 << 7)
0062 };
0063
0064 struct tipc_link_entry {
0065     struct tipc_link *link;
0066     spinlock_t lock; /* per link */
0067     u32 mtu;
0068     struct sk_buff_head inputq;
0069     struct tipc_media_addr maddr;
0070 };
0071
0072 struct tipc_bclink_entry {
0073     struct tipc_link *link;
0074     struct sk_buff_head inputq1;
0075     struct sk_buff_head arrvq;
0076     struct sk_buff_head inputq2;
0077     struct sk_buff_head namedq;
0078     u16 named_rcv_nxt;
0079     bool named_open;
0080 };
0081
0082 /**
0083  * struct tipc_node - TIPC node structure
0084  * @addr: network address of node
0085  * @kref: reference counter to node object
0086  * @lock: rwlock governing access to structure
0087  * @net: the applicable net namespace
0088  * @hash: links to adjacent nodes in unsorted hash chain
0089  * @inputq: pointer to input queue containing messages for msg event
0090  * @namedq: pointer to name table input queue with name table messages
0091  * @active_links: bearer ids of active links, used as index into links[] array
0092  * @links: array containing references to all links to node
0093  * @bc_entry: broadcast link entry
0094  * @action_flags: bit mask of different types of node actions
0095  * @state: connectivity state vs peer node
0096  * @preliminary: a preliminary node or not
0097  * @failover_sent: failover sent or not
0098  * @sync_point: sequence number where synch/failover is finished
0099  * @list: links to adjacent nodes in sorted list of cluster's nodes
0100  * @working_links: number of working links to node (both active and standby)
0101  * @link_cnt: number of links to node
0102  * @capabilities: bitmap, indicating peer node's functional capabilities
0103  * @signature: node instance identifier
0104  * @link_id: local and remote bearer ids of changing link, if any
0105  * @peer_id: 128-bit ID of peer
0106  * @peer_id_string: ID string of peer
0107  * @publ_list: list of publications
0108  * @conn_sks: list of connections (FIXME)
0109  * @timer: node's keepalive timer
0110  * @keepalive_intv: keepalive interval in milliseconds
0111  * @rcu: rcu struct for tipc_node
0112  * @delete_at: indicates the time for deleting a down node
0113  * @peer_net: peer's net namespace
0114  * @peer_hash_mix: hash for this peer (FIXME)
0115  * @crypto_rx: RX crypto handler
0116  */
0117 struct tipc_node {
0118     u32 addr;
0119     struct kref kref;
0120     rwlock_t lock;
0121     struct net *net;
0122     struct hlist_node hash;
0123     int active_links[2];
0124     struct tipc_link_entry links[MAX_BEARERS];
0125     struct tipc_bclink_entry bc_entry;
0126     int action_flags;
0127     struct list_head list;
0128     int state;
0129     bool preliminary;
0130     bool failover_sent;
0131     u16 sync_point;
0132     int link_cnt;
0133     u16 working_links;
0134     u16 capabilities;
0135     u32 signature;
0136     u32 link_id;
0137     u8 peer_id[16];
0138     char peer_id_string[NODE_ID_STR_LEN];
0139     struct list_head publ_list;
0140     struct list_head conn_sks;
0141     unsigned long keepalive_intv;
0142     struct timer_list timer;
0143     struct rcu_head rcu;
0144     unsigned long delete_at;
0145     struct net *peer_net;
0146     u32 peer_hash_mix;
0147 #ifdef CONFIG_TIPC_CRYPTO
0148     struct tipc_crypto *crypto_rx;
0149 #endif
0150 };
0151
0152 /* Node FSM states and events:
0153  */
0154 enum {
0155     SELF_DOWN_PEER_DOWN    = 0xdd,
0156     SELF_UP_PEER_UP        = 0xaa,
0157     SELF_DOWN_PEER_LEAVING = 0xd1,
0158     SELF_UP_PEER_COMING    = 0xac,
0159     SELF_COMING_PEER_UP    = 0xca,
0160     SELF_LEAVING_PEER_DOWN = 0x1d,
0161     NODE_FAILINGOVER       = 0xf0,
0162     NODE_SYNCHING          = 0xcc
0163 };
0164
0165 enum {
0166     SELF_ESTABL_CONTACT_EVT = 0xece,
0167     SELF_LOST_CONTACT_EVT   = 0x1ce,
0168     PEER_ESTABL_CONTACT_EVT = 0x9ece,
0169     PEER_LOST_CONTACT_EVT   = 0x91ce,
0170     NODE_FAILOVER_BEGIN_EVT = 0xfbe,
0171     NODE_FAILOVER_END_EVT   = 0xfee,
0172     NODE_SYNCH_BEGIN_EVT    = 0xcbe,
0173     NODE_SYNCH_END_EVT      = 0xcee
0174 };
0175
0176 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
0177                   struct sk_buff_head *xmitq,
0178                   struct tipc_media_addr **maddr);
0179 static void tipc_node_link_down(struct tipc_node *n, int bearer_id,
0180                 bool delete);
0181 static void node_lost_contact(struct tipc_node *n, struct sk_buff_head *inputq);
0182 static void tipc_node_delete(struct tipc_node *node);
0183 static void tipc_node_timeout(struct timer_list *t);
0184 static void tipc_node_fsm_evt(struct tipc_node *n, int evt);
0185 static struct tipc_node *tipc_node_find(struct net *net, u32 addr);
0186 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id);
0187 static bool node_is_up(struct tipc_node *n);
0188 static void tipc_node_delete_from_list(struct tipc_node *node);
0189
0190 struct tipc_sock_conn {
0191     u32 port;
0192     u32 peer_port;
0193     u32 peer_node;
0194     struct list_head list;
0195 };
0196
0197 static struct tipc_link *node_active_link(struct tipc_node *n, int sel)
0198 {
0199     int bearer_id = n->active_links[sel & 1];
0200
0201     if (unlikely(bearer_id == INVALID_BEARER_ID))
0202         return NULL;
0203
0204     return n->links[bearer_id].link;
0205 }
0206
0207 int tipc_node_get_mtu(struct net *net, u32 addr, u32 sel, bool connected)
0208 {
0209     struct tipc_node *n;
0210     int bearer_id;
0211     unsigned int mtu = MAX_MSG_SIZE;
0212
0213     n = tipc_node_find(net, addr);
0214     if (unlikely(!n))
0215         return mtu;
0216
0217     /* Allow MAX_MSG_SIZE when building connection oriented message
0218      * if they are in the same core network
0219      */
0220     if (n->peer_net && connected) {
0221         tipc_node_put(n);
0222         return mtu;
0223     }
0224
0225     bearer_id = n->active_links[sel & 1];
0226     if (likely(bearer_id != INVALID_BEARER_ID))
0227         mtu = n->links[bearer_id].mtu;
0228     tipc_node_put(n);
0229     return mtu;
0230 }
0231
0232 bool tipc_node_get_id(struct net *net, u32 addr, u8 *id)
0233 {
0234     u8 *own_id = tipc_own_id(net);
0235     struct tipc_node *n;
0236
0237     if (!own_id)
0238         return true;
0239
0240     if (addr == tipc_own_addr(net)) {
0241         memcpy(id, own_id, TIPC_NODEID_LEN);
0242         return true;
0243     }
0244     n = tipc_node_find(net, addr);
0245     if (!n)
0246         return false;
0247
0248     memcpy(id, &n->peer_id, TIPC_NODEID_LEN);
0249     tipc_node_put(n);
0250     return true;
0251 }
0252
0253 u16 tipc_node_get_capabilities(struct net *net, u32 addr)
0254 {
0255     struct tipc_node *n;
0256     u16 caps;
0257
0258     n = tipc_node_find(net, addr);
0259     if (unlikely(!n))
0260         return TIPC_NODE_CAPABILITIES;
0261     caps = n->capabilities;
0262     tipc_node_put(n);
0263     return caps;
0264 }
0265
0266 u32 tipc_node_get_addr(struct tipc_node *node)
0267 {
0268     return (node) ? node->addr : 0;
0269 }
0270
0271 char *tipc_node_get_id_str(struct tipc_node *node)
0272 {
0273     return node->peer_id_string;
0274 }
0275
0276 #ifdef CONFIG_TIPC_CRYPTO
0277 /**
0278  * tipc_node_crypto_rx - Retrieve crypto RX handle from node
0279  * @__n: target tipc_node
0280  * Note: node ref counter must be held first!
0281  */
0282 struct tipc_crypto *tipc_node_crypto_rx(struct tipc_node *__n)
0283 {
0284     return (__n) ? __n->crypto_rx : NULL;
0285 }
0286
0287 struct tipc_crypto *tipc_node_crypto_rx_by_list(struct list_head *pos)
0288 {
0289     return container_of(pos, struct tipc_node, list)->crypto_rx;
0290 }
0291
0292 struct tipc_crypto *tipc_node_crypto_rx_by_addr(struct net *net, u32 addr)
0293 {
0294     struct tipc_node *n;
0295
0296     n = tipc_node_find(net, addr);
0297     return (n) ? n->crypto_rx : NULL;
0298 }
0299 #endif
0300
0301 static void tipc_node_free(struct rcu_head *rp)
0302 {
0303     struct tipc_node *n = container_of(rp, struct tipc_node, rcu);
0304
0305 #ifdef CONFIG_TIPC_CRYPTO
0306     tipc_crypto_stop(&n->crypto_rx);
0307 #endif
0308     kfree(n);
0309 }
0310
0311 static void tipc_node_kref_release(struct kref *kref)
0312 {
0313     struct tipc_node *n = container_of(kref, struct tipc_node, kref);
0314
0315     kfree(n->bc_entry.link);
0316     call_rcu(&n->rcu, tipc_node_free);
0317 }
0318
0319 void tipc_node_put(struct tipc_node *node)
0320 {
0321     kref_put(&node->kref, tipc_node_kref_release);
0322 }
0323
0324 void tipc_node_get(struct tipc_node *node)
0325 {
0326     kref_get(&node->kref);
0327 }
0328
0329 /*
0330  * tipc_node_find - locate specified node object, if it exists
0331  */
0332 static struct tipc_node *tipc_node_find(struct net *net, u32 addr)
0333 {
0334     struct tipc_net *tn = tipc_net(net);
0335     struct tipc_node *node;
0336     unsigned int thash = tipc_hashfn(addr);
0337
0338     rcu_read_lock();
0339     hlist_for_each_entry_rcu(node, &tn->node_htable[thash], hash) {
0340         if (node->addr != addr || node->preliminary)
0341             continue;
0342         if (!kref_get_unless_zero(&node->kref))
0343             node = NULL;
0344         break;
0345     }
0346     rcu_read_unlock();
0347     return node;
0348 }
0349
0350 /* tipc_node_find_by_id - locate specified node object by its 128-bit id
0351  * Note: this function is called only when a discovery request failed
0352  * to find the node by its 32-bit id, and is not time critical
0353  */
0354 static struct tipc_node *tipc_node_find_by_id(struct net *net, u8 *id)
0355 {
0356     struct tipc_net *tn = tipc_net(net);
0357     struct tipc_node *n;
0358     bool found = false;
0359
0360     rcu_read_lock();
0361     list_for_each_entry_rcu(n, &tn->node_list, list) {
0362         read_lock_bh(&n->lock);
0363         if (!memcmp(id, n->peer_id, 16) &&
0364             kref_get_unless_zero(&n->kref))
0365             found = true;
0366         read_unlock_bh(&n->lock);
0367         if (found)
0368             break;
0369     }
0370     rcu_read_unlock();
0371     return found ? n : NULL;
0372 }
0373
0374 static void tipc_node_read_lock(struct tipc_node *n)
0375     __acquires(n->lock)
0376 {
0377     read_lock_bh(&n->lock);
0378 }
0379
0380 static void tipc_node_read_unlock(struct tipc_node *n)
0381     __releases(n->lock)
0382 {
0383     read_unlock_bh(&n->lock);
0384 }
0385
0386 static void tipc_node_write_lock(struct tipc_node *n)
0387     __acquires(n->lock)
0388 {
0389     write_lock_bh(&n->lock);
0390 }
0391
0392 static void tipc_node_write_unlock_fast(struct tipc_node *n)
0393     __releases(n->lock)
0394 {
0395     write_unlock_bh(&n->lock);
0396 }
0397
0398 static void tipc_node_write_unlock(struct tipc_node *n)
0399     __releases(n->lock)
0400 {
0401     struct tipc_socket_addr sk;
0402     struct net *net = n->net;
0403     u32 flags = n->action_flags;
0404     struct list_head *publ_list;
0405     struct tipc_uaddr ua;
0406     u32 bearer_id, node;
0407
0408     if (likely(!flags)) {
0409         write_unlock_bh(&n->lock);
0410         return;
0411     }
0412
0413     tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_NODE_SCOPE,
0414            TIPC_LINK_STATE, n->addr, n->addr);
0415     sk.ref = n->link_id;
0416     sk.node = tipc_own_addr(net);
0417     node = n->addr;
0418     bearer_id = n->link_id & 0xffff;
0419     publ_list = &n->publ_list;
0420
0421     n->action_flags &= ~(TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |
0422                  TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP);
0423
0424     write_unlock_bh(&n->lock);
0425
0426     if (flags & TIPC_NOTIFY_NODE_DOWN)
0427         tipc_publ_notify(net, publ_list, node, n->capabilities);
0428
0429     if (flags & TIPC_NOTIFY_NODE_UP)
0430         tipc_named_node_up(net, node, n->capabilities);
0431
0432     if (flags & TIPC_NOTIFY_LINK_UP) {
0433         tipc_mon_peer_up(net, node, bearer_id);
0434         tipc_nametbl_publish(net, &ua, &sk, sk.ref);
0435     }
0436     if (flags & TIPC_NOTIFY_LINK_DOWN) {
0437         tipc_mon_peer_down(net, node, bearer_id);
0438         tipc_nametbl_withdraw(net, &ua, &sk, sk.ref);
0439     }
0440 }
0441
0442 static void tipc_node_assign_peer_net(struct tipc_node *n, u32 hash_mixes)
0443 {
0444     int net_id = tipc_netid(n->net);
0445     struct tipc_net *tn_peer;
0446     struct net *tmp;
0447     u32 hash_chk;
0448
0449     if (n->peer_net)
0450         return;
0451
0452     for_each_net_rcu(tmp) {
0453         tn_peer = tipc_net(tmp);
0454         if (!tn_peer)
0455             continue;
0456         /* Integrity checking whether node exists in namespace or not */
0457         if (tn_peer->net_id != net_id)
0458             continue;
0459         if (memcmp(n->peer_id, tn_peer->node_id, NODE_ID_LEN))
0460             continue;
0461         hash_chk = tipc_net_hash_mixes(tmp, tn_peer->random);
0462         if (hash_mixes ^ hash_chk)
0463             continue;
0464         n->peer_net = tmp;
0465         n->peer_hash_mix = hash_mixes;
0466         break;
0467     }
0468 }
0469
0470 struct tipc_node *tipc_node_create(struct net *net, u32 addr, u8 *peer_id,
0471                    u16 capabilities, u32 hash_mixes,
0472                    bool preliminary)
0473 {
0474     struct tipc_net *tn = net_generic(net, tipc_net_id);
0475     struct tipc_link *l, *snd_l = tipc_bc_sndlink(net);
0476     struct tipc_node *n, *temp_node;
0477     unsigned long intv;
0478     int bearer_id;
0479     int i;
0480
0481     spin_lock_bh(&tn->node_list_lock);
0482     n = tipc_node_find(net, addr) ?:
0483         tipc_node_find_by_id(net, peer_id);
0484     if (n) {
0485         if (!n->preliminary)
0486             goto update;
0487         if (preliminary)
0488             goto exit;
0489         /* A preliminary node becomes "real" now, refresh its data */
0490         tipc_node_write_lock(n);
0491         if (!tipc_link_bc_create(net, tipc_own_addr(net), addr, peer_id, U16_MAX,
0492                      tipc_link_min_win(snd_l), tipc_link_max_win(snd_l),
0493                      n->capabilities, &n->bc_entry.inputq1,
0494                      &n->bc_entry.namedq, snd_l, &n->bc_entry.link)) {
0495             pr_warn("Broadcast rcv link refresh failed, no memory\n");
0496             tipc_node_write_unlock_fast(n);
0497             tipc_node_put(n);
0498             n = NULL;
0499             goto exit;
0500         }
0501         n->preliminary = false;
0502         n->addr = addr;
0503         hlist_del_rcu(&n->hash);
0504         hlist_add_head_rcu(&n->hash,
0505                    &tn->node_htable[tipc_hashfn(addr)]);
0506         list_del_rcu(&n->list);
0507         list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
0508             if (n->addr < temp_node->addr)
0509                 break;
0510         }
0511         list_add_tail_rcu(&n->list, &temp_node->list);
0512         tipc_node_write_unlock_fast(n);
0513
0514 update:
0515         if (n->peer_hash_mix ^ hash_mixes)
0516             tipc_node_assign_peer_net(n, hash_mixes);
0517         if (n->capabilities == capabilities)
0518             goto exit;
0519         /* Same node may come back with new capabilities */
0520         tipc_node_write_lock(n);
0521         n->capabilities = capabilities;
0522         for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
0523             l = n->links[bearer_id].link;
0524             if (l)
0525                 tipc_link_update_caps(l, capabilities);
0526         }
0527         tipc_node_write_unlock_fast(n);
0528
0529         /* Calculate cluster capabilities */
0530         tn->capabilities = TIPC_NODE_CAPABILITIES;
0531         list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
0532             tn->capabilities &= temp_node->capabilities;
0533         }
0534
0535         tipc_bcast_toggle_rcast(net,
0536                     (tn->capabilities & TIPC_BCAST_RCAST));
0537
0538         goto exit;
0539     }
0540     n = kzalloc(sizeof(*n), GFP_ATOMIC);
0541     if (!n) {
0542         pr_warn("Node creation failed, no memory\n");
0543         goto exit;
0544     }
0545     tipc_nodeid2string(n->peer_id_string, peer_id);
0546 #ifdef CONFIG_TIPC_CRYPTO
0547     if (unlikely(tipc_crypto_start(&n->crypto_rx, net, n))) {
0548         pr_warn("Failed to start crypto RX(%s)!\n", n->peer_id_string);
0549         kfree(n);
0550         n = NULL;
0551         goto exit;
0552     }
0553 #endif
0554     n->addr = addr;
0555     n->preliminary = preliminary;
0556     memcpy(&n->peer_id, peer_id, 16);
0557     n->net = net;
0558     n->peer_net = NULL;
0559     n->peer_hash_mix = 0;
0560     /* Assign kernel local namespace if exists */
0561     tipc_node_assign_peer_net(n, hash_mixes);
0562     n->capabilities = capabilities;
0563     kref_init(&n->kref);
0564     rwlock_init(&n->lock);
0565     INIT_HLIST_NODE(&n->hash);
0566     INIT_LIST_HEAD(&n->list);
0567     INIT_LIST_HEAD(&n->publ_list);
0568     INIT_LIST_HEAD(&n->conn_sks);
0569     skb_queue_head_init(&n->bc_entry.namedq);
0570     skb_queue_head_init(&n->bc_entry.inputq1);
0571     __skb_queue_head_init(&n->bc_entry.arrvq);
0572     skb_queue_head_init(&n->bc_entry.inputq2);
0573     for (i = 0; i < MAX_BEARERS; i++)
0574         spin_lock_init(&n->links[i].lock);
0575     n->state = SELF_DOWN_PEER_LEAVING;
0576     n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
0577     n->signature = INVALID_NODE_SIG;
0578     n->active_links[0] = INVALID_BEARER_ID;
0579     n->active_links[1] = INVALID_BEARER_ID;
0580     if (!preliminary &&
0581         !tipc_link_bc_create(net, tipc_own_addr(net), addr, peer_id, U16_MAX,
0582                  tipc_link_min_win(snd_l), tipc_link_max_win(snd_l),
0583                  n->capabilities, &n->bc_entry.inputq1,
0584                  &n->bc_entry.namedq, snd_l, &n->bc_entry.link)) {
0585         pr_warn("Broadcast rcv link creation failed, no memory\n");
0586         kfree(n);
0587         n = NULL;
0588         goto exit;
0589     }
0590     tipc_node_get(n);
0591     timer_setup(&n->timer, tipc_node_timeout, 0);
0592     /* Start a slow timer anyway, crypto needs it */
0593     n->keepalive_intv = 10000;
0594     intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
0595     if (!mod_timer(&n->timer, intv))
0596         tipc_node_get(n);
0597     hlist_add_head_rcu(&n->hash, &tn->node_htable[tipc_hashfn(addr)]);
0598     list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
0599         if (n->addr < temp_node->addr)
0600             break;
0601     }
0602     list_add_tail_rcu(&n->list, &temp_node->list);
0603     /* Calculate cluster capabilities */
0604     tn->capabilities = TIPC_NODE_CAPABILITIES;
0605     list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
0606         tn->capabilities &= temp_node->capabilities;
0607     }
0608     tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
0609     trace_tipc_node_create(n, true, " ");
0610 exit:
0611     spin_unlock_bh(&tn->node_list_lock);
0612     return n;
0613 }
0614
0615 static void tipc_node_calculate_timer(struct tipc_node *n, struct tipc_link *l)
0616 {
0617     unsigned long tol = tipc_link_tolerance(l);
0618     unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4;
0619
0620     /* Link with lowest tolerance determines timer interval */
0621     if (intv < n->keepalive_intv)
0622         n->keepalive_intv = intv;
0623
0624     /* Ensure link's abort limit corresponds to current tolerance */
0625     tipc_link_set_abort_limit(l, tol / n->keepalive_intv);
0626 }
0627
0628 static void tipc_node_delete_from_list(struct tipc_node *node)
0629 {
0630 #ifdef CONFIG_TIPC_CRYPTO
0631     tipc_crypto_key_flush(node->crypto_rx);
0632 #endif
0633     list_del_rcu(&node->list);
0634     hlist_del_rcu(&node->hash);
0635     tipc_node_put(node);
0636 }
0637
0638 static void tipc_node_delete(struct tipc_node *node)
0639 {
0640     trace_tipc_node_delete(node, true, " ");
0641     tipc_node_delete_from_list(node);
0642
0643     del_timer_sync(&node->timer);
0644     tipc_node_put(node);
0645 }
0646
0647 void tipc_node_stop(struct net *net)
0648 {
0649     struct tipc_net *tn = tipc_net(net);
0650     struct tipc_node *node, *t_node;
0651
0652     spin_lock_bh(&tn->node_list_lock);
0653     list_for_each_entry_safe(node, t_node, &tn->node_list, list)
0654         tipc_node_delete(node);
0655     spin_unlock_bh(&tn->node_list_lock);
0656 }
0657
0658 void tipc_node_subscribe(struct net *net, struct list_head *subscr, u32 addr)
0659 {
0660     struct tipc_node *n;
0661
0662     if (in_own_node(net, addr))
0663         return;
0664
0665     n = tipc_node_find(net, addr);
0666     if (!n) {
0667         pr_warn("Node subscribe rejected, unknown node 0x%x\n", addr);
0668         return;
0669     }
0670     tipc_node_write_lock(n);
0671     list_add_tail(subscr, &n->publ_list);
0672     tipc_node_write_unlock_fast(n);
0673     tipc_node_put(n);
0674 }
0675
0676 void tipc_node_unsubscribe(struct net *net, struct list_head *subscr, u32 addr)
0677 {
0678     struct tipc_node *n;
0679
0680     if (in_own_node(net, addr))
0681         return;
0682
0683     n = tipc_node_find(net, addr);
0684     if (!n) {
0685         pr_warn("Node unsubscribe rejected, unknown node 0x%x\n", addr);
0686         return;
0687     }
0688     tipc_node_write_lock(n);
0689     list_del_init(subscr);
0690     tipc_node_write_unlock_fast(n);
0691     tipc_node_put(n);
0692 }
0693
0694 int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port)
0695 {
0696     struct tipc_node *node;
0697     struct tipc_sock_conn *conn;
0698     int err = 0;
0699
0700     if (in_own_node(net, dnode))
0701         return 0;
0702
0703     node = tipc_node_find(net, dnode);
0704     if (!node) {
0705         pr_warn("Connecting sock to node 0x%x failed\n", dnode);
0706         return -EHOSTUNREACH;
0707     }
0708     conn = kmalloc(sizeof(*conn), GFP_ATOMIC);
0709     if (!conn) {
0710         err = -EHOSTUNREACH;
0711         goto exit;
0712     }
0713     conn->peer_node = dnode;
0714     conn->port = port;
0715     conn->peer_port = peer_port;
0716
0717     tipc_node_write_lock(node);
0718     list_add_tail(&conn->list, &node->conn_sks);
0719     tipc_node_write_unlock(node);
0720 exit:
0721     tipc_node_put(node);
0722     return err;
0723 }
0724
0725 void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port)
0726 {
0727     struct tipc_node *node;
0728     struct tipc_sock_conn *conn, *safe;
0729
0730     if (in_own_node(net, dnode))
0731         return;
0732
0733     node = tipc_node_find(net, dnode);
0734     if (!node)
0735         return;
0736
0737     tipc_node_write_lock(node);
0738     list_for_each_entry_safe(conn, safe, &node->conn_sks, list) {
0739         if (port != conn->port)
0740             continue;
0741         list_del(&conn->list);
0742         kfree(conn);
0743     }
0744     tipc_node_write_unlock(node);
0745     tipc_node_put(node);
0746 }
0747
0748 static void  tipc_node_clear_links(struct tipc_node *node)
0749 {
0750     int i;
0751
0752     for (i = 0; i < MAX_BEARERS; i++) {
0753         struct tipc_link_entry *le = &node->links[i];
0754
0755         if (le->link) {
0756             kfree(le->link);
0757             le->link = NULL;
0758             node->link_cnt--;
0759         }
0760     }
0761 }
0762
0763 /* tipc_node_cleanup - delete nodes that does not
0764  * have active links for NODE_CLEANUP_AFTER time
0765  */
0766 static bool tipc_node_cleanup(struct tipc_node *peer)
0767 {
0768     struct tipc_node *temp_node;
0769     struct tipc_net *tn = tipc_net(peer->net);
0770     bool deleted = false;
0771
0772     /* If lock held by tipc_node_stop() the node will be deleted anyway */
0773     if (!spin_trylock_bh(&tn->node_list_lock))
0774         return false;
0775
0776     tipc_node_write_lock(peer);
0777
0778     if (!node_is_up(peer) && time_after(jiffies, peer->delete_at)) {
0779         tipc_node_clear_links(peer);
0780         tipc_node_delete_from_list(peer);
0781         deleted = true;
0782     }
0783     tipc_node_write_unlock(peer);
0784
0785     if (!deleted) {
0786         spin_unlock_bh(&tn->node_list_lock);
0787         return deleted;
0788     }
0789
0790     /* Calculate cluster capabilities */
0791     tn->capabilities = TIPC_NODE_CAPABILITIES;
0792     list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
0793         tn->capabilities &= temp_node->capabilities;
0794     }
0795     tipc_bcast_toggle_rcast(peer->net,
0796                 (tn->capabilities & TIPC_BCAST_RCAST));
0797     spin_unlock_bh(&tn->node_list_lock);
0798     return deleted;
0799 }
0800
0801 /* tipc_node_timeout - handle expiration of node timer
0802  */
0803 static void tipc_node_timeout(struct timer_list *t)
0804 {
0805     struct tipc_node *n = from_timer(n, t, timer);
0806     struct tipc_link_entry *le;
0807     struct sk_buff_head xmitq;
0808     int remains = n->link_cnt;
0809     int bearer_id;
0810     int rc = 0;
0811
0812     trace_tipc_node_timeout(n, false, " ");
0813     if (!node_is_up(n) && tipc_node_cleanup(n)) {
0814         /*Removing the reference of Timer*/
0815         tipc_node_put(n);
0816         return;
0817     }
0818
0819 #ifdef CONFIG_TIPC_CRYPTO
0820     /* Take any crypto key related actions first */
0821     tipc_crypto_timeout(n->crypto_rx);
0822 #endif
0823     __skb_queue_head_init(&xmitq);
0824
0825     /* Initial node interval to value larger (10 seconds), then it will be
0826      * recalculated with link lowest tolerance
0827      */
0828     tipc_node_read_lock(n);
0829     n->keepalive_intv = 10000;
0830     tipc_node_read_unlock(n);
0831     for (bearer_id = 0; remains && (bearer_id < MAX_BEARERS); bearer_id++) {
0832         tipc_node_read_lock(n);
0833         le = &n->links[bearer_id];
0834         if (le->link) {
0835             spin_lock_bh(&le->lock);
0836             /* Link tolerance may change asynchronously: */
0837             tipc_node_calculate_timer(n, le->link);
0838             rc = tipc_link_timeout(le->link, &xmitq);
0839             spin_unlock_bh(&le->lock);
0840             remains--;
0841         }
0842         tipc_node_read_unlock(n);
0843         tipc_bearer_xmit(n->net, bearer_id, &xmitq, &le->maddr, n);
0844         if (rc & TIPC_LINK_DOWN_EVT)
0845             tipc_node_link_down(n, bearer_id, false);
0846     }
0847     mod_timer(&n->timer, jiffies + msecs_to_jiffies(n->keepalive_intv));
0848 }
0849
0850 /**
0851  * __tipc_node_link_up - handle addition of link
0852  * @n: target tipc_node
0853  * @bearer_id: id of the bearer
0854  * @xmitq: queue for messages to be xmited on
0855  * Node lock must be held by caller
0856  * Link becomes active (alone or shared) or standby, depending on its priority.
0857  */
0858 static void __tipc_node_link_up(struct tipc_node *n, int bearer_id,
0859                 struct sk_buff_head *xmitq)
0860 {
0861     int *slot0 = &n->active_links[0];
0862     int *slot1 = &n->active_links[1];
0863     struct tipc_link *ol = node_active_link(n, 0);
0864     struct tipc_link *nl = n->links[bearer_id].link;
0865
0866     if (!nl || tipc_link_is_up(nl))
0867         return;
0868
0869     tipc_link_fsm_evt(nl, LINK_ESTABLISH_EVT);
0870     if (!tipc_link_is_up(nl))
0871         return;
0872
0873     n->working_links++;
0874     n->action_flags |= TIPC_NOTIFY_LINK_UP;
0875     n->link_id = tipc_link_id(nl);
0876
0877     /* Leave room for tunnel header when returning 'mtu' to users: */
0878     n->links[bearer_id].mtu = tipc_link_mss(nl);
0879
0880     tipc_bearer_add_dest(n->net, bearer_id, n->addr);
0881     tipc_bcast_inc_bearer_dst_cnt(n->net, bearer_id);
0882
0883     pr_debug("Established link <%s> on network plane %c\n",
0884          tipc_link_name(nl), tipc_link_plane(nl));
0885     trace_tipc_node_link_up(n, true, " ");
0886
0887     /* Ensure that a STATE message goes first */
0888     tipc_link_build_state_msg(nl, xmitq);
0889
0890     /* First link? => give it both slots */
0891     if (!ol) {
0892         *slot0 = bearer_id;
0893         *slot1 = bearer_id;
0894         tipc_node_fsm_evt(n, SELF_ESTABL_CONTACT_EVT);
0895         n->action_flags |= TIPC_NOTIFY_NODE_UP;
0896         tipc_link_set_active(nl, true);
0897         tipc_bcast_add_peer(n->net, nl, xmitq);
0898         return;
0899     }
0900
0901     /* Second link => redistribute slots */
0902     if (tipc_link_prio(nl) > tipc_link_prio(ol)) {
0903         pr_debug("Old link <%s> becomes standby\n", tipc_link_name(ol));
0904         *slot0 = bearer_id;
0905         *slot1 = bearer_id;
0906         tipc_link_set_active(nl, true);
0907         tipc_link_set_active(ol, false);
0908     } else if (tipc_link_prio(nl) == tipc_link_prio(ol)) {
0909         tipc_link_set_active(nl, true);
0910         *slot1 = bearer_id;
0911     } else {
0912         pr_debug("New link <%s> is standby\n", tipc_link_name(nl));
0913     }
0914
0915     /* Prepare synchronization with first link */
0916     tipc_link_tnl_prepare(ol, nl, SYNCH_MSG, xmitq);
0917 }
0918
0919 /**
0920  * tipc_node_link_up - handle addition of link
0921  * @n: target tipc_node
0922  * @bearer_id: id of the bearer
0923  * @xmitq: queue for messages to be xmited on
0924  *
0925  * Link becomes active (alone or shared) or standby, depending on its priority.
0926  */
0927 static void tipc_node_link_up(struct tipc_node *n, int bearer_id,
0928                   struct sk_buff_head *xmitq)
0929 {
0930     struct tipc_media_addr *maddr;
0931
0932     tipc_node_write_lock(n);
0933     __tipc_node_link_up(n, bearer_id, xmitq);
0934     maddr = &n->links[bearer_id].maddr;
0935     tipc_bearer_xmit(n->net, bearer_id, xmitq, maddr, n);
0936     tipc_node_write_unlock(n);
0937 }
0938
0939 /**
0940  * tipc_node_link_failover() - start failover in case "half-failover"
0941  *
0942  * This function is only called in a very special situation where link
0943  * failover can be already started on peer node but not on this node.
0944  * This can happen when e.g.::
0945  *
0946  *  1. Both links <1A-2A>, <1B-2B> down
0947  *  2. Link endpoint 2A up, but 1A still down (e.g. due to network
0948  *  disturbance, wrong session, etc.)
0949  *  3. Link <1B-2B> up
0950  *  4. Link endpoint 2A down (e.g. due to link tolerance timeout)
0951  *  5. Node 2 starts failover onto link <1B-2B>
0952  *
0953  *  ==> Node 1 does never start link/node failover!
0954  *
0955  * @n: tipc node structure
0956  * @l: link peer endpoint failingover (- can be NULL)
0957  * @tnl: tunnel link
0958  * @xmitq: queue for messages to be xmited on tnl link later
0959  */
0960 static void tipc_node_link_failover(struct tipc_node *n, struct tipc_link *l,
0961                     struct tipc_link *tnl,
0962                     struct sk_buff_head *xmitq)
0963 {
0964     /* Avoid to be "self-failover" that can never end */
0965     if (!tipc_link_is_up(tnl))
0966         return;
0967
0968     /* Don't rush, failure link may be in the process of resetting */
0969     if (l && !tipc_link_is_reset(l))
0970         return;
0971
0972     tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
0973     tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
0974
0975     n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
0976     tipc_link_failover_prepare(l, tnl, xmitq);
0977
0978     if (l)
0979         tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
0980     tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
0981 }
0982
0983 /**
0984  * __tipc_node_link_down - handle loss of link
0985  * @n: target tipc_node
0986  * @bearer_id: id of the bearer
0987  * @xmitq: queue for messages to be xmited on
0988  * @maddr: output media address of the bearer
0989  */
0990 static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
0991                   struct sk_buff_head *xmitq,
0992                   struct tipc_media_addr **maddr)
0993 {
0994     struct tipc_link_entry *le = &n->links[*bearer_id];
0995     int *slot0 = &n->active_links[0];
0996     int *slot1 = &n->active_links[1];
0997     int i, highest = 0, prio;
0998     struct tipc_link *l, *_l, *tnl;
0999
1000     l = n->links[*bearer_id].link;
1001     if (!l || tipc_link_is_reset(l))
1002         return;
1003
1004     n->working_links--;
1005     n->action_flags |= TIPC_NOTIFY_LINK_DOWN;
1006     n->link_id = tipc_link_id(l);
1007
1008     tipc_bearer_remove_dest(n->net, *bearer_id, n->addr);
1009
1010     pr_debug("Lost link <%s> on network plane %c\n",
1011          tipc_link_name(l), tipc_link_plane(l));
1012
1013     /* Select new active link if any available */
1014     *slot0 = INVALID_BEARER_ID;
1015     *slot1 = INVALID_BEARER_ID;
1016     for (i = 0; i < MAX_BEARERS; i++) {
1017         _l = n->links[i].link;
1018         if (!_l || !tipc_link_is_up(_l))
1019             continue;
1020         if (_l == l)
1021             continue;
1022         prio = tipc_link_prio(_l);
1023         if (prio < highest)
1024             continue;
1025         if (prio > highest) {
1026             highest = prio;
1027             *slot0 = i;
1028             *slot1 = i;
1029             continue;
1030         }
1031         *slot1 = i;
1032     }
1033
1034     if (!node_is_up(n)) {
1035         if (tipc_link_peer_is_down(l))
1036             tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1037         tipc_node_fsm_evt(n, SELF_LOST_CONTACT_EVT);
1038         trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down!");
1039         tipc_link_fsm_evt(l, LINK_RESET_EVT);
1040         tipc_link_reset(l);
1041         tipc_link_build_reset_msg(l, xmitq);
1042         *maddr = &n->links[*bearer_id].maddr;
1043         node_lost_contact(n, &le->inputq);
1044         tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
1045         return;
1046     }
1047     tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id);
1048
1049     /* There is still a working link => initiate failover */
1050     *bearer_id = n->active_links[0];
1051     tnl = n->links[*bearer_id].link;
1052     tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
1053     tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
1054     n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
1055     tipc_link_tnl_prepare(l, tnl, FAILOVER_MSG, xmitq);
1056     trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link down -> failover!");
1057     tipc_link_reset(l);
1058     tipc_link_fsm_evt(l, LINK_RESET_EVT);
1059     tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
1060     tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
1061     *maddr = &n->links[*bearer_id].maddr;
1062 }
1063
1064 static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete)
1065 {
1066     struct tipc_link_entry *le = &n->links[bearer_id];
1067     struct tipc_media_addr *maddr = NULL;
1068     struct tipc_link *l = le->link;
1069     int old_bearer_id = bearer_id;
1070     struct sk_buff_head xmitq;
1071
1072     if (!l)
1073         return;
1074
1075     __skb_queue_head_init(&xmitq);
1076
1077     tipc_node_write_lock(n);
1078     if (!tipc_link_is_establishing(l)) {
1079         __tipc_node_link_down(n, &bearer_id, &xmitq, &maddr);
1080     } else {
1081         /* Defuse pending tipc_node_link_up() */
1082         tipc_link_reset(l);
1083         tipc_link_fsm_evt(l, LINK_RESET_EVT);
1084     }
1085     if (delete) {
1086         kfree(l);
1087         le->link = NULL;
1088         n->link_cnt--;
1089     }
1090     trace_tipc_node_link_down(n, true, "node link down or deleted!");
1091     tipc_node_write_unlock(n);
1092     if (delete)
1093         tipc_mon_remove_peer(n->net, n->addr, old_bearer_id);
1094     if (!skb_queue_empty(&xmitq))
1095         tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr, n);
1096     tipc_sk_rcv(n->net, &le->inputq);
1097 }
1098
1099 static bool node_is_up(struct tipc_node *n)
1100 {
1101     return n->active_links[0] != INVALID_BEARER_ID;
1102 }
1103
1104 bool tipc_node_is_up(struct net *net, u32 addr)
1105 {
1106     struct tipc_node *n;
1107     bool retval = false;
1108
1109     if (in_own_node(net, addr))
1110         return true;
1111
1112     n = tipc_node_find(net, addr);
1113     if (!n)
1114         return false;
1115     retval = node_is_up(n);
1116     tipc_node_put(n);
1117     return retval;
1118 }
1119
1120 static u32 tipc_node_suggest_addr(struct net *net, u32 addr)
1121 {
1122     struct tipc_node *n;
1123
1124     addr ^= tipc_net(net)->random;
1125     while ((n = tipc_node_find(net, addr))) {
1126         tipc_node_put(n);
1127         addr++;
1128     }
1129     return addr;
1130 }
1131
1132 /* tipc_node_try_addr(): Check if addr can be used by peer, suggest other if not
1133  * Returns suggested address if any, otherwise 0
1134  */
1135 u32 tipc_node_try_addr(struct net *net, u8 *id, u32 addr)
1136 {
1137     struct tipc_net *tn = tipc_net(net);
1138     struct tipc_node *n;
1139     bool preliminary;
1140     u32 sugg_addr;
1141
1142     /* Suggest new address if some other peer is using this one */
1143     n = tipc_node_find(net, addr);
1144     if (n) {
1145         if (!memcmp(n->peer_id, id, NODE_ID_LEN))
1146             addr = 0;
1147         tipc_node_put(n);
1148         if (!addr)
1149             return 0;
1150         return tipc_node_suggest_addr(net, addr);
1151     }
1152
1153     /* Suggest previously used address if peer is known */
1154     n = tipc_node_find_by_id(net, id);
1155     if (n) {
1156         sugg_addr = n->addr;
1157         preliminary = n->preliminary;
1158         tipc_node_put(n);
1159         if (!preliminary)
1160             return sugg_addr;
1161     }
1162
1163     /* Even this node may be in conflict */
1164     if (tn->trial_addr == addr)
1165         return tipc_node_suggest_addr(net, addr);
1166
1167     return 0;
1168 }
1169
1170 void tipc_node_check_dest(struct net *net, u32 addr,
1171               u8 *peer_id, struct tipc_bearer *b,
1172               u16 capabilities, u32 signature, u32 hash_mixes,
1173               struct tipc_media_addr *maddr,
1174               bool *respond, bool *dupl_addr)
1175 {
1176     struct tipc_node *n;
1177     struct tipc_link *l;
1178     struct tipc_link_entry *le;
1179     bool addr_match = false;
1180     bool sign_match = false;
1181     bool link_up = false;
1182     bool accept_addr = false;
1183     bool reset = true;
1184     char *if_name;
1185     unsigned long intv;
1186     u16 session;
1187
1188     *dupl_addr = false;
1189     *respond = false;
1190
1191     n = tipc_node_create(net, addr, peer_id, capabilities, hash_mixes,
1192                  false);
1193     if (!n)
1194         return;
1195
1196     tipc_node_write_lock(n);
1197
1198     le = &n->links[b->identity];
1199
1200     /* Prepare to validate requesting node's signature and media address */
1201     l = le->link;
1202     link_up = l && tipc_link_is_up(l);
1203     addr_match = l && !memcmp(&le->maddr, maddr, sizeof(*maddr));
1204     sign_match = (signature == n->signature);
1205
1206     /* These three flags give us eight permutations: */
1207
1208     if (sign_match && addr_match && link_up) {
1209         /* All is fine. Do nothing. */
1210         reset = false;
1211         /* Peer node is not a container/local namespace */
1212         if (!n->peer_hash_mix)
1213             n->peer_hash_mix = hash_mixes;
1214     } else if (sign_match && addr_match && !link_up) {
1215         /* Respond. The link will come up in due time */
1216         *respond = true;
1217     } else if (sign_match && !addr_match && link_up) {
1218         /* Peer has changed i/f address without rebooting.
1219          * If so, the link will reset soon, and the next
1220          * discovery will be accepted. So we can ignore it.
1221          * It may also be a cloned or malicious peer having
1222          * chosen the same node address and signature as an
1223          * existing one.
1224          * Ignore requests until the link goes down, if ever.
1225          */
1226         *dupl_addr = true;
1227     } else if (sign_match && !addr_match && !link_up) {
1228         /* Peer link has changed i/f address without rebooting.
1229          * It may also be a cloned or malicious peer; we can't
1230          * distinguish between the two.
1231          * The signature is correct, so we must accept.
1232          */
1233         accept_addr = true;
1234         *respond = true;
1235     } else if (!sign_match && addr_match && link_up) {
1236         /* Peer node rebooted. Two possibilities:
1237          *  - Delayed re-discovery; this link endpoint has already
1238          *    reset and re-established contact with the peer, before
1239          *    receiving a discovery message from that node.
1240          *    (The peer happened to receive one from this node first).
1241          *  - The peer came back so fast that our side has not
1242          *    discovered it yet. Probing from this side will soon
1243          *    reset the link, since there can be no working link
1244          *    endpoint at the peer end, and the link will re-establish.
1245          *  Accept the signature, since it comes from a known peer.
1246          */
1247         n->signature = signature;
1248     } else if (!sign_match && addr_match && !link_up) {
1249         /*  The peer node has rebooted.
1250          *  Accept signature, since it is a known peer.
1251          */
1252         n->signature = signature;
1253         *respond = true;
1254     } else if (!sign_match && !addr_match && link_up) {
1255         /* Peer rebooted with new address, or a new/duplicate peer.
1256          * Ignore until the link goes down, if ever.
1257          */
1258         *dupl_addr = true;
1259     } else if (!sign_match && !addr_match && !link_up) {
1260         /* Peer rebooted with new address, or it is a new peer.
1261          * Accept signature and address.
1262          */
1263         n->signature = signature;
1264         accept_addr = true;
1265         *respond = true;
1266     }
1267
1268     if (!accept_addr)
1269         goto exit;
1270
1271     /* Now create new link if not already existing */
1272     if (!l) {
1273         if (n->link_cnt == 2)
1274             goto exit;
1275
1276         if_name = strchr(b->name, ':') + 1;
1277         get_random_bytes(&session, sizeof(u16));
1278         if (!tipc_link_create(net, if_name, b->identity, b->tolerance,
1279                       b->net_plane, b->mtu, b->priority,
1280                       b->min_win, b->max_win, session,
1281                       tipc_own_addr(net), addr, peer_id,
1282                       n->capabilities,
1283                       tipc_bc_sndlink(n->net), n->bc_entry.link,
1284                       &le->inputq,
1285                       &n->bc_entry.namedq, &l)) {
1286             *respond = false;
1287             goto exit;
1288         }
1289         trace_tipc_link_reset(l, TIPC_DUMP_ALL, "link created!");
1290         tipc_link_reset(l);
1291         tipc_link_fsm_evt(l, LINK_RESET_EVT);
1292         if (n->state == NODE_FAILINGOVER)
1293             tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
1294         le->link = l;
1295         n->link_cnt++;
1296         tipc_node_calculate_timer(n, l);
1297         if (n->link_cnt == 1) {
1298             intv = jiffies + msecs_to_jiffies(n->keepalive_intv);
1299             if (!mod_timer(&n->timer, intv))
1300                 tipc_node_get(n);
1301         }
1302     }
1303     memcpy(&le->maddr, maddr, sizeof(*maddr));
1304 exit:
1305     tipc_node_write_unlock(n);
1306     if (reset && l && !tipc_link_is_reset(l))
1307         tipc_node_link_down(n, b->identity, false);
1308     tipc_node_put(n);
1309 }
1310
1311 void tipc_node_delete_links(struct net *net, int bearer_id)
1312 {
1313     struct tipc_net *tn = net_generic(net, tipc_net_id);
1314     struct tipc_node *n;
1315
1316     rcu_read_lock();
1317     list_for_each_entry_rcu(n, &tn->node_list, list) {
1318         tipc_node_link_down(n, bearer_id, true);
1319     }
1320     rcu_read_unlock();
1321 }
1322
1323 static void tipc_node_reset_links(struct tipc_node *n)
1324 {
1325     int i;
1326
1327     pr_warn("Resetting all links to %x\n", n->addr);
1328
1329     trace_tipc_node_reset_links(n, true, " ");
1330     for (i = 0; i < MAX_BEARERS; i++) {
1331         tipc_node_link_down(n, i, false);
1332     }
1333 }
1334
1335 /* tipc_node_fsm_evt - node finite state machine
1336  * Determines when contact is allowed with peer node
1337  */
1338 static void tipc_node_fsm_evt(struct tipc_node *n, int evt)
1339 {
1340     int state = n->state;
1341
1342     switch (state) {
1343     case SELF_DOWN_PEER_DOWN:
1344         switch (evt) {
1345         case SELF_ESTABL_CONTACT_EVT:
1346             state = SELF_UP_PEER_COMING;
1347             break;
1348         case PEER_ESTABL_CONTACT_EVT:
1349             state = SELF_COMING_PEER_UP;
1350             break;
1351         case SELF_LOST_CONTACT_EVT:
1352         case PEER_LOST_CONTACT_EVT:
1353             break;
1354         case NODE_SYNCH_END_EVT:
1355         case NODE_SYNCH_BEGIN_EVT:
1356         case NODE_FAILOVER_BEGIN_EVT:
1357         case NODE_FAILOVER_END_EVT:
1358         default:
1359             goto illegal_evt;
1360         }
1361         break;
1362     case SELF_UP_PEER_UP:
1363         switch (evt) {
1364         case SELF_LOST_CONTACT_EVT:
1365             state = SELF_DOWN_PEER_LEAVING;
1366             break;
1367         case PEER_LOST_CONTACT_EVT:
1368             state = SELF_LEAVING_PEER_DOWN;
1369             break;
1370         case NODE_SYNCH_BEGIN_EVT:
1371             state = NODE_SYNCHING;
1372             break;
1373         case NODE_FAILOVER_BEGIN_EVT:
1374             state = NODE_FAILINGOVER;
1375             break;
1376         case SELF_ESTABL_CONTACT_EVT:
1377         case PEER_ESTABL_CONTACT_EVT:
1378         case NODE_SYNCH_END_EVT:
1379         case NODE_FAILOVER_END_EVT:
1380             break;
1381         default:
1382             goto illegal_evt;
1383         }
1384         break;
1385     case SELF_DOWN_PEER_LEAVING:
1386         switch (evt) {
1387         case PEER_LOST_CONTACT_EVT:
1388             state = SELF_DOWN_PEER_DOWN;
1389             break;
1390         case SELF_ESTABL_CONTACT_EVT:
1391         case PEER_ESTABL_CONTACT_EVT:
1392         case SELF_LOST_CONTACT_EVT:
1393             break;
1394         case NODE_SYNCH_END_EVT:
1395         case NODE_SYNCH_BEGIN_EVT:
1396         case NODE_FAILOVER_BEGIN_EVT:
1397         case NODE_FAILOVER_END_EVT:
1398         default:
1399             goto illegal_evt;
1400         }
1401         break;
1402     case SELF_UP_PEER_COMING:
1403         switch (evt) {
1404         case PEER_ESTABL_CONTACT_EVT:
1405             state = SELF_UP_PEER_UP;
1406             break;
1407         case SELF_LOST_CONTACT_EVT:
1408             state = SELF_DOWN_PEER_DOWN;
1409             break;
1410         case SELF_ESTABL_CONTACT_EVT:
1411         case PEER_LOST_CONTACT_EVT:
1412         case NODE_SYNCH_END_EVT:
1413         case NODE_FAILOVER_BEGIN_EVT:
1414             break;
1415         case NODE_SYNCH_BEGIN_EVT:
1416         case NODE_FAILOVER_END_EVT:
1417         default:
1418             goto illegal_evt;
1419         }
1420         break;
1421     case SELF_COMING_PEER_UP:
1422         switch (evt) {
1423         case SELF_ESTABL_CONTACT_EVT:
1424             state = SELF_UP_PEER_UP;
1425             break;
1426         case PEER_LOST_CONTACT_EVT:
1427             state = SELF_DOWN_PEER_DOWN;
1428             break;
1429         case SELF_LOST_CONTACT_EVT:
1430         case PEER_ESTABL_CONTACT_EVT:
1431             break;
1432         case NODE_SYNCH_END_EVT:
1433         case NODE_SYNCH_BEGIN_EVT:
1434         case NODE_FAILOVER_BEGIN_EVT:
1435         case NODE_FAILOVER_END_EVT:
1436         default:
1437             goto illegal_evt;
1438         }
1439         break;
1440     case SELF_LEAVING_PEER_DOWN:
1441         switch (evt) {
1442         case SELF_LOST_CONTACT_EVT:
1443             state = SELF_DOWN_PEER_DOWN;
1444             break;
1445         case SELF_ESTABL_CONTACT_EVT:
1446         case PEER_ESTABL_CONTACT_EVT:
1447         case PEER_LOST_CONTACT_EVT:
1448             break;
1449         case NODE_SYNCH_END_EVT:
1450         case NODE_SYNCH_BEGIN_EVT:
1451         case NODE_FAILOVER_BEGIN_EVT:
1452         case NODE_FAILOVER_END_EVT:
1453         default:
1454             goto illegal_evt;
1455         }
1456         break;
1457     case NODE_FAILINGOVER:
1458         switch (evt) {
1459         case SELF_LOST_CONTACT_EVT:
1460             state = SELF_DOWN_PEER_LEAVING;
1461             break;
1462         case PEER_LOST_CONTACT_EVT:
1463             state = SELF_LEAVING_PEER_DOWN;
1464             break;
1465         case NODE_FAILOVER_END_EVT:
1466             state = SELF_UP_PEER_UP;
1467             break;
1468         case NODE_FAILOVER_BEGIN_EVT:
1469         case SELF_ESTABL_CONTACT_EVT:
1470         case PEER_ESTABL_CONTACT_EVT:
1471             break;
1472         case NODE_SYNCH_BEGIN_EVT:
1473         case NODE_SYNCH_END_EVT:
1474         default:
1475             goto illegal_evt;
1476         }
1477         break;
1478     case NODE_SYNCHING:
1479         switch (evt) {
1480         case SELF_LOST_CONTACT_EVT:
1481             state = SELF_DOWN_PEER_LEAVING;
1482             break;
1483         case PEER_LOST_CONTACT_EVT:
1484             state = SELF_LEAVING_PEER_DOWN;
1485             break;
1486         case NODE_SYNCH_END_EVT:
1487             state = SELF_UP_PEER_UP;
1488             break;
1489         case NODE_FAILOVER_BEGIN_EVT:
1490             state = NODE_FAILINGOVER;
1491             break;
1492         case NODE_SYNCH_BEGIN_EVT:
1493         case SELF_ESTABL_CONTACT_EVT:
1494         case PEER_ESTABL_CONTACT_EVT:
1495             break;
1496         case NODE_FAILOVER_END_EVT:
1497         default:
1498             goto illegal_evt;
1499         }
1500         break;
1501     default:
1502         pr_err("Unknown node fsm state %x\n", state);
1503         break;
1504     }
1505     trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1506     n->state = state;
1507     return;
1508
1509 illegal_evt:
1510     pr_err("Illegal node fsm evt %x in state %x\n", evt, state);
1511     trace_tipc_node_fsm(n->peer_id, n->state, state, evt);
1512 }
1513
1514 static void node_lost_contact(struct tipc_node *n,
1515                   struct sk_buff_head *inputq)
1516 {
1517     struct tipc_sock_conn *conn, *safe;
1518     struct tipc_link *l;
1519     struct list_head *conns = &n->conn_sks;
1520     struct sk_buff *skb;
1521     uint i;
1522
1523     pr_debug("Lost contact with %x\n", n->addr);
1524     n->delete_at = jiffies + msecs_to_jiffies(NODE_CLEANUP_AFTER);
1525     trace_tipc_node_lost_contact(n, true, " ");
1526
1527     /* Clean up broadcast state */
1528     tipc_bcast_remove_peer(n->net, n->bc_entry.link);
1529     skb_queue_purge(&n->bc_entry.namedq);
1530
1531     /* Abort any ongoing link failover */
1532     for (i = 0; i < MAX_BEARERS; i++) {
1533         l = n->links[i].link;
1534         if (l)
1535             tipc_link_fsm_evt(l, LINK_FAILOVER_END_EVT);
1536     }
1537
1538     /* Notify publications from this node */
1539     n->action_flags |= TIPC_NOTIFY_NODE_DOWN;
1540     n->peer_net = NULL;
1541     n->peer_hash_mix = 0;
1542     /* Notify sockets connected to node */
1543     list_for_each_entry_safe(conn, safe, conns, list) {
1544         skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG,
1545                       SHORT_H_SIZE, 0, tipc_own_addr(n->net),
1546                       conn->peer_node, conn->port,
1547                       conn->peer_port, TIPC_ERR_NO_NODE);
1548         if (likely(skb))
1549             skb_queue_tail(inputq, skb);
1550         list_del(&conn->list);
1551         kfree(conn);
1552     }
1553 }
1554
1555 /**
1556  * tipc_node_get_linkname - get the name of a link
1557  *
1558  * @net: the applicable net namespace
1559  * @bearer_id: id of the bearer
1560  * @addr: peer node address
1561  * @linkname: link name output buffer
1562  * @len: size of @linkname output buffer
1563  *
1564  * Return: 0 on success
1565  */
1566 int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 addr,
1567                char *linkname, size_t len)
1568 {
1569     struct tipc_link *link;
1570     int err = -EINVAL;
1571     struct tipc_node *node = tipc_node_find(net, addr);
1572
1573     if (!node)
1574         return err;
1575
1576     if (bearer_id >= MAX_BEARERS)
1577         goto exit;
1578
1579     tipc_node_read_lock(node);
1580     link = node->links[bearer_id].link;
1581     if (link) {
1582         strncpy(linkname, tipc_link_name(link), len);
1583         err = 0;
1584     }
1585     tipc_node_read_unlock(node);
1586 exit:
1587     tipc_node_put(node);
1588     return err;
1589 }
1590
1591 /* Caller should hold node lock for the passed node */
1592 static int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node)
1593 {
1594     void *hdr;
1595     struct nlattr *attrs;
1596
1597     hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1598               NLM_F_MULTI, TIPC_NL_NODE_GET);
1599     if (!hdr)
1600         return -EMSGSIZE;
1601
1602     attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NODE);
1603     if (!attrs)
1604         goto msg_full;
1605
1606     if (nla_put_u32(msg->skb, TIPC_NLA_NODE_ADDR, node->addr))
1607         goto attr_msg_full;
1608     if (node_is_up(node))
1609         if (nla_put_flag(msg->skb, TIPC_NLA_NODE_UP))
1610             goto attr_msg_full;
1611
1612     nla_nest_end(msg->skb, attrs);
1613     genlmsg_end(msg->skb, hdr);
1614
1615     return 0;
1616
1617 attr_msg_full:
1618     nla_nest_cancel(msg->skb, attrs);
1619 msg_full:
1620     genlmsg_cancel(msg->skb, hdr);
1621
1622     return -EMSGSIZE;
1623 }
1624
1625 static void tipc_lxc_xmit(struct net *peer_net, struct sk_buff_head *list)
1626 {
1627     struct tipc_msg *hdr = buf_msg(skb_peek(list));
1628     struct sk_buff_head inputq;
1629
1630     switch (msg_user(hdr)) {
1631     case TIPC_LOW_IMPORTANCE:
1632     case TIPC_MEDIUM_IMPORTANCE:
1633     case TIPC_HIGH_IMPORTANCE:
1634     case TIPC_CRITICAL_IMPORTANCE:
1635         if (msg_connected(hdr) || msg_named(hdr) ||
1636             msg_direct(hdr)) {
1637             tipc_loopback_trace(peer_net, list);
1638             spin_lock_init(&list->lock);
1639             tipc_sk_rcv(peer_net, list);
1640             return;
1641         }
1642         if (msg_mcast(hdr)) {
1643             tipc_loopback_trace(peer_net, list);
1644             skb_queue_head_init(&inputq);
1645             tipc_sk_mcast_rcv(peer_net, list, &inputq);
1646             __skb_queue_purge(list);
1647             skb_queue_purge(&inputq);
1648             return;
1649         }
1650         return;
1651     case MSG_FRAGMENTER:
1652         if (tipc_msg_assemble(list)) {
1653             tipc_loopback_trace(peer_net, list);
1654             skb_queue_head_init(&inputq);
1655             tipc_sk_mcast_rcv(peer_net, list, &inputq);
1656             __skb_queue_purge(list);
1657             skb_queue_purge(&inputq);
1658         }
1659         return;
1660     case GROUP_PROTOCOL:
1661     case CONN_MANAGER:
1662         tipc_loopback_trace(peer_net, list);
1663         spin_lock_init(&list->lock);
1664         tipc_sk_rcv(peer_net, list);
1665         return;
1666     case LINK_PROTOCOL:
1667     case NAME_DISTRIBUTOR:
1668     case TUNNEL_PROTOCOL:
1669     case BCAST_PROTOCOL:
1670         return;
1671     default:
1672         return;
1673     }
1674 }
1675
1676 /**
1677  * tipc_node_xmit() - general link level function for message sending
1678  * @net: the applicable net namespace
1679  * @list: chain of buffers containing message
1680  * @dnode: address of destination node
1681  * @selector: a number used for deterministic link selection
1682  * Consumes the buffer chain.
1683  * Return: 0 if success, otherwise: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE,-ENOBUF
1684  */
1685 int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
1686            u32 dnode, int selector)
1687 {
1688     struct tipc_link_entry *le = NULL;
1689     struct tipc_node *n;
1690     struct sk_buff_head xmitq;
1691     bool node_up = false;
1692     int bearer_id;
1693     int rc;
1694
1695     if (in_own_node(net, dnode)) {
1696         tipc_loopback_trace(net, list);
1697         spin_lock_init(&list->lock);
1698         tipc_sk_rcv(net, list);
1699         return 0;
1700     }
1701
1702     n = tipc_node_find(net, dnode);
1703     if (unlikely(!n)) {
1704         __skb_queue_purge(list);
1705         return -EHOSTUNREACH;
1706     }
1707
1708     tipc_node_read_lock(n);
1709     node_up = node_is_up(n);
1710     if (node_up && n->peer_net && check_net(n->peer_net)) {
1711         /* xmit inner linux container */
1712         tipc_lxc_xmit(n->peer_net, list);
1713         if (likely(skb_queue_empty(list))) {
1714             tipc_node_read_unlock(n);
1715             tipc_node_put(n);
1716             return 0;
1717         }
1718     }
1719
1720     bearer_id = n->active_links[selector & 1];
1721     if (unlikely(bearer_id == INVALID_BEARER_ID)) {
1722         tipc_node_read_unlock(n);
1723         tipc_node_put(n);
1724         __skb_queue_purge(list);
1725         return -EHOSTUNREACH;
1726     }
1727
1728     __skb_queue_head_init(&xmitq);
1729     le = &n->links[bearer_id];
1730     spin_lock_bh(&le->lock);
1731     rc = tipc_link_xmit(le->link, list, &xmitq);
1732     spin_unlock_bh(&le->lock);
1733     tipc_node_read_unlock(n);
1734
1735     if (unlikely(rc == -ENOBUFS))
1736         tipc_node_link_down(n, bearer_id, false);
1737     else
1738         tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
1739
1740     tipc_node_put(n);
1741
1742     return rc;
1743 }
1744
1745 /* tipc_node_xmit_skb(): send single buffer to destination
1746  * Buffers sent via this function are generally TIPC_SYSTEM_IMPORTANCE
1747  * messages, which will not be rejected
1748  * The only exception is datagram messages rerouted after secondary
1749  * lookup, which are rare and safe to dispose of anyway.
1750  */
1751 int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode,
1752                u32 selector)
1753 {
1754     struct sk_buff_head head;
1755
1756     __skb_queue_head_init(&head);
1757     __skb_queue_tail(&head, skb);
1758     tipc_node_xmit(net, &head, dnode, selector);
1759     return 0;
1760 }
1761
1762 /* tipc_node_distr_xmit(): send single buffer msgs to individual destinations
1763  * Note: this is only for SYSTEM_IMPORTANCE messages, which cannot be rejected
1764  */
1765 int tipc_node_distr_xmit(struct net *net, struct sk_buff_head *xmitq)
1766 {
1767     struct sk_buff *skb;
1768     u32 selector, dnode;
1769
1770     while ((skb = __skb_dequeue(xmitq))) {
1771         selector = msg_origport(buf_msg(skb));
1772         dnode = msg_destnode(buf_msg(skb));
1773         tipc_node_xmit_skb(net, skb, dnode, selector);
1774     }
1775     return 0;
1776 }
1777
1778 void tipc_node_broadcast(struct net *net, struct sk_buff *skb, int rc_dests)
1779 {
1780     struct sk_buff_head xmitq;
1781     struct sk_buff *txskb;
1782     struct tipc_node *n;
1783     u16 dummy;
1784     u32 dst;
1785
1786     /* Use broadcast if all nodes support it */
1787     if (!rc_dests && tipc_bcast_get_mode(net) != BCLINK_MODE_RCAST) {
1788         __skb_queue_head_init(&xmitq);
1789         __skb_queue_tail(&xmitq, skb);
1790         tipc_bcast_xmit(net, &xmitq, &dummy);
1791         return;
1792     }
1793
1794     /* Otherwise use legacy replicast method */
1795     rcu_read_lock();
1796     list_for_each_entry_rcu(n, tipc_nodes(net), list) {
1797         dst = n->addr;
1798         if (in_own_node(net, dst))
1799             continue;
1800         if (!node_is_up(n))
1801             continue;
1802         txskb = pskb_copy(skb, GFP_ATOMIC);
1803         if (!txskb)
1804             break;
1805         msg_set_destnode(buf_msg(txskb), dst);
1806         tipc_node_xmit_skb(net, txskb, dst, 0);
1807     }
1808     rcu_read_unlock();
1809     kfree_skb(skb);
1810 }
1811
1812 static void tipc_node_mcast_rcv(struct tipc_node *n)
1813 {
1814     struct tipc_bclink_entry *be = &n->bc_entry;
1815
1816     /* 'arrvq' is under inputq2's lock protection */
1817     spin_lock_bh(&be->inputq2.lock);
1818     spin_lock_bh(&be->inputq1.lock);
1819     skb_queue_splice_tail_init(&be->inputq1, &be->arrvq);
1820     spin_unlock_bh(&be->inputq1.lock);
1821     spin_unlock_bh(&be->inputq2.lock);
1822     tipc_sk_mcast_rcv(n->net, &be->arrvq, &be->inputq2);
1823 }
1824
1825 static void tipc_node_bc_sync_rcv(struct tipc_node *n, struct tipc_msg *hdr,
1826                   int bearer_id, struct sk_buff_head *xmitq)
1827 {
1828     struct tipc_link *ucl;
1829     int rc;
1830
1831     rc = tipc_bcast_sync_rcv(n->net, n->bc_entry.link, hdr, xmitq);
1832
1833     if (rc & TIPC_LINK_DOWN_EVT) {
1834         tipc_node_reset_links(n);
1835         return;
1836     }
1837
1838     if (!(rc & TIPC_LINK_SND_STATE))
1839         return;
1840
1841     /* If probe message, a STATE response will be sent anyway */
1842     if (msg_probe(hdr))
1843         return;
1844
1845     /* Produce a STATE message carrying broadcast NACK */
1846     tipc_node_read_lock(n);
1847     ucl = n->links[bearer_id].link;
1848     if (ucl)
1849         tipc_link_build_state_msg(ucl, xmitq);
1850     tipc_node_read_unlock(n);
1851 }
1852
1853 /**
1854  * tipc_node_bc_rcv - process TIPC broadcast packet arriving from off-node
1855  * @net: the applicable net namespace
1856  * @skb: TIPC packet
1857  * @bearer_id: id of bearer message arrived on
1858  *
1859  * Invoked with no locks held.
1860  */
1861 static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id)
1862 {
1863     int rc;
1864     struct sk_buff_head xmitq;
1865     struct tipc_bclink_entry *be;
1866     struct tipc_link_entry *le;
1867     struct tipc_msg *hdr = buf_msg(skb);
1868     int usr = msg_user(hdr);
1869     u32 dnode = msg_destnode(hdr);
1870     struct tipc_node *n;
1871
1872     __skb_queue_head_init(&xmitq);
1873
1874     /* If NACK for other node, let rcv link for that node peek into it */
1875     if ((usr == BCAST_PROTOCOL) && (dnode != tipc_own_addr(net)))
1876         n = tipc_node_find(net, dnode);
1877     else
1878         n = tipc_node_find(net, msg_prevnode(hdr));
1879     if (!n) {
1880         kfree_skb(skb);
1881         return;
1882     }
1883     be = &n->bc_entry;
1884     le = &n->links[bearer_id];
1885
1886     rc = tipc_bcast_rcv(net, be->link, skb);
1887
1888     /* Broadcast ACKs are sent on a unicast link */
1889     if (rc & TIPC_LINK_SND_STATE) {
1890         tipc_node_read_lock(n);
1891         tipc_link_build_state_msg(le->link, &xmitq);
1892         tipc_node_read_unlock(n);
1893     }
1894
1895     if (!skb_queue_empty(&xmitq))
1896         tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
1897
1898     if (!skb_queue_empty(&be->inputq1))
1899         tipc_node_mcast_rcv(n);
1900
1901     /* Handle NAME_DISTRIBUTOR messages sent from 1.7 nodes */
1902     if (!skb_queue_empty(&n->bc_entry.namedq))
1903         tipc_named_rcv(net, &n->bc_entry.namedq,
1904                    &n->bc_entry.named_rcv_nxt,
1905                    &n->bc_entry.named_open);
1906
1907     /* If reassembly or retransmission failure => reset all links to peer */
1908     if (rc & TIPC_LINK_DOWN_EVT)
1909         tipc_node_reset_links(n);
1910
1911     tipc_node_put(n);
1912 }
1913
1914 /**
1915  * tipc_node_check_state - check and if necessary update node state
1916  * @n: target tipc_node
1917  * @skb: TIPC packet
1918  * @bearer_id: identity of bearer delivering the packet
1919  * @xmitq: queue for messages to be xmited on
1920  * Return: true if state and msg are ok, otherwise false
1921  */
1922 static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb,
1923                   int bearer_id, struct sk_buff_head *xmitq)
1924 {
1925     struct tipc_msg *hdr = buf_msg(skb);
1926     int usr = msg_user(hdr);
1927     int mtyp = msg_type(hdr);
1928     u16 oseqno = msg_seqno(hdr);
1929     u16 exp_pkts = msg_msgcnt(hdr);
1930     u16 rcv_nxt, syncpt, dlv_nxt, inputq_len;
1931     int state = n->state;
1932     struct tipc_link *l, *tnl, *pl = NULL;
1933     struct tipc_media_addr *maddr;
1934     int pb_id;
1935
1936     if (trace_tipc_node_check_state_enabled()) {
1937         trace_tipc_skb_dump(skb, false, "skb for node state check");
1938         trace_tipc_node_check_state(n, true, " ");
1939     }
1940     l = n->links[bearer_id].link;
1941     if (!l)
1942         return false;
1943     rcv_nxt = tipc_link_rcv_nxt(l);
1944
1945
1946     if (likely((state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL)))
1947         return true;
1948
1949     /* Find parallel link, if any */
1950     for (pb_id = 0; pb_id < MAX_BEARERS; pb_id++) {
1951         if ((pb_id != bearer_id) && n->links[pb_id].link) {
1952             pl = n->links[pb_id].link;
1953             break;
1954         }
1955     }
1956
1957     if (!tipc_link_validate_msg(l, hdr)) {
1958         trace_tipc_skb_dump(skb, false, "PROTO invalid (2)!");
1959         trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (2)!");
1960         return false;
1961     }
1962
1963     /* Check and update node accesibility if applicable */
1964     if (state == SELF_UP_PEER_COMING) {
1965         if (!tipc_link_is_up(l))
1966             return true;
1967         if (!msg_peer_link_is_up(hdr))
1968             return true;
1969         tipc_node_fsm_evt(n, PEER_ESTABL_CONTACT_EVT);
1970     }
1971
1972     if (state == SELF_DOWN_PEER_LEAVING) {
1973         if (msg_peer_node_is_up(hdr))
1974             return false;
1975         tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT);
1976         return true;
1977     }
1978
1979     if (state == SELF_LEAVING_PEER_DOWN)
1980         return false;
1981
1982     /* Ignore duplicate packets */
1983     if ((usr != LINK_PROTOCOL) && less(oseqno, rcv_nxt))
1984         return true;
1985
1986     /* Initiate or update failover mode if applicable */
1987     if ((usr == TUNNEL_PROTOCOL) && (mtyp == FAILOVER_MSG)) {
1988         syncpt = oseqno + exp_pkts - 1;
1989         if (pl && !tipc_link_is_reset(pl)) {
1990             __tipc_node_link_down(n, &pb_id, xmitq, &maddr);
1991             trace_tipc_node_link_down(n, true,
1992                           "node link down <- failover!");
1993             tipc_skb_queue_splice_tail_init(tipc_link_inputq(pl),
1994                             tipc_link_inputq(l));
1995         }
1996
1997         /* If parallel link was already down, and this happened before
1998          * the tunnel link came up, node failover was never started.
1999          * Ensure that a FAILOVER_MSG is sent to get peer out of
2000          * NODE_FAILINGOVER state, also this node must accept
2001          * TUNNEL_MSGs from peer.
2002          */
2003         if (n->state != NODE_FAILINGOVER)
2004             tipc_node_link_failover(n, pl, l, xmitq);
2005
2006         /* If pkts arrive out of order, use lowest calculated syncpt */
2007         if (less(syncpt, n->sync_point))
2008             n->sync_point = syncpt;
2009     }
2010
2011     /* Open parallel link when tunnel link reaches synch point */
2012     if ((n->state == NODE_FAILINGOVER) && tipc_link_is_up(l)) {
2013         if (!more(rcv_nxt, n->sync_point))
2014             return true;
2015         tipc_node_fsm_evt(n, NODE_FAILOVER_END_EVT);
2016         if (pl)
2017             tipc_link_fsm_evt(pl, LINK_FAILOVER_END_EVT);
2018         return true;
2019     }
2020
2021     /* No syncing needed if only one link */
2022     if (!pl || !tipc_link_is_up(pl))
2023         return true;
2024
2025     /* Initiate synch mode if applicable */
2026     if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG) && (oseqno == 1)) {
2027         if (n->capabilities & TIPC_TUNNEL_ENHANCED)
2028             syncpt = msg_syncpt(hdr);
2029         else
2030             syncpt = msg_seqno(msg_inner_hdr(hdr)) + exp_pkts - 1;
2031         if (!tipc_link_is_up(l))
2032             __tipc_node_link_up(n, bearer_id, xmitq);
2033         if (n->state == SELF_UP_PEER_UP) {
2034             n->sync_point = syncpt;
2035             tipc_link_fsm_evt(l, LINK_SYNCH_BEGIN_EVT);
2036             tipc_node_fsm_evt(n, NODE_SYNCH_BEGIN_EVT);
2037         }
2038     }
2039
2040     /* Open tunnel link when parallel link reaches synch point */
2041     if (n->state == NODE_SYNCHING) {
2042         if (tipc_link_is_synching(l)) {
2043             tnl = l;
2044         } else {
2045             tnl = pl;
2046             pl = l;
2047         }
2048         inputq_len = skb_queue_len(tipc_link_inputq(pl));
2049         dlv_nxt = tipc_link_rcv_nxt(pl) - inputq_len;
2050         if (more(dlv_nxt, n->sync_point)) {
2051             tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
2052             tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
2053             return true;
2054         }
2055         if (l == pl)
2056             return true;
2057         if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG))
2058             return true;
2059         if (usr == LINK_PROTOCOL)
2060             return true;
2061         return false;
2062     }
2063     return true;
2064 }
2065
2066 /**
2067  * tipc_rcv - process TIPC packets/messages arriving from off-node
2068  * @net: the applicable net namespace
2069  * @skb: TIPC packet
2070  * @b: pointer to bearer message arrived on
2071  *
2072  * Invoked with no locks held. Bearer pointer must point to a valid bearer
2073  * structure (i.e. cannot be NULL), but bearer can be inactive.
2074  */
2075 void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
2076 {
2077     struct sk_buff_head xmitq;
2078     struct tipc_link_entry *le;
2079     struct tipc_msg *hdr;
2080     struct tipc_node *n;
2081     int bearer_id = b->identity;
2082     u32 self = tipc_own_addr(net);
2083     int usr, rc = 0;
2084     u16 bc_ack;
2085 #ifdef CONFIG_TIPC_CRYPTO
2086     struct tipc_ehdr *ehdr;
2087
2088     /* Check if message must be decrypted first */
2089     if (TIPC_SKB_CB(skb)->decrypted || !tipc_ehdr_validate(skb))
2090         goto rcv;
2091
2092     ehdr = (struct tipc_ehdr *)skb->data;
2093     if (likely(ehdr->user != LINK_CONFIG)) {
2094         n = tipc_node_find(net, ntohl(ehdr->addr));
2095         if (unlikely(!n))
2096             goto discard;
2097     } else {
2098         n = tipc_node_find_by_id(net, ehdr->id);
2099     }
2100     tipc_crypto_rcv(net, (n) ? n->crypto_rx : NULL, &skb, b);
2101     if (!skb)
2102         return;
2103
2104 rcv:
2105 #endif
2106     /* Ensure message is well-formed before touching the header */
2107     if (unlikely(!tipc_msg_validate(&skb)))
2108         goto discard;
2109     __skb_queue_head_init(&xmitq);
2110     hdr = buf_msg(skb);
2111     usr = msg_user(hdr);
2112     bc_ack = msg_bcast_ack(hdr);
2113
2114     /* Handle arrival of discovery or broadcast packet */
2115     if (unlikely(msg_non_seq(hdr))) {
2116         if (unlikely(usr == LINK_CONFIG))
2117             return tipc_disc_rcv(net, skb, b);
2118         else
2119             return tipc_node_bc_rcv(net, skb, bearer_id);
2120     }
2121
2122     /* Discard unicast link messages destined for another node */
2123     if (unlikely(!msg_short(hdr) && (msg_destnode(hdr) != self)))
2124         goto discard;
2125
2126     /* Locate neighboring node that sent packet */
2127     n = tipc_node_find(net, msg_prevnode(hdr));
2128     if (unlikely(!n))
2129         goto discard;
2130     le = &n->links[bearer_id];
2131
2132     /* Ensure broadcast reception is in synch with peer's send state */
2133     if (unlikely(usr == LINK_PROTOCOL)) {
2134         if (unlikely(skb_linearize(skb))) {
2135             tipc_node_put(n);
2136             goto discard;
2137         }
2138         hdr = buf_msg(skb);
2139         tipc_node_bc_sync_rcv(n, hdr, bearer_id, &xmitq);
2140     } else if (unlikely(tipc_link_acked(n->bc_entry.link) != bc_ack)) {
2141         tipc_bcast_ack_rcv(net, n->bc_entry.link, hdr);
2142     }
2143
2144     /* Receive packet directly if conditions permit */
2145     tipc_node_read_lock(n);
2146     if (likely((n->state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL))) {
2147         spin_lock_bh(&le->lock);
2148         if (le->link) {
2149             rc = tipc_link_rcv(le->link, skb, &xmitq);
2150             skb = NULL;
2151         }
2152         spin_unlock_bh(&le->lock);
2153     }
2154     tipc_node_read_unlock(n);
2155
2156     /* Check/update node state before receiving */
2157     if (unlikely(skb)) {
2158         if (unlikely(skb_linearize(skb)))
2159             goto out_node_put;
2160         tipc_node_write_lock(n);
2161         if (tipc_node_check_state(n, skb, bearer_id, &xmitq)) {
2162             if (le->link) {
2163                 rc = tipc_link_rcv(le->link, skb, &xmitq);
2164                 skb = NULL;
2165             }
2166         }
2167         tipc_node_write_unlock(n);
2168     }
2169
2170     if (unlikely(rc & TIPC_LINK_UP_EVT))
2171         tipc_node_link_up(n, bearer_id, &xmitq);
2172
2173     if (unlikely(rc & TIPC_LINK_DOWN_EVT))
2174         tipc_node_link_down(n, bearer_id, false);
2175
2176     if (unlikely(!skb_queue_empty(&n->bc_entry.namedq)))
2177         tipc_named_rcv(net, &n->bc_entry.namedq,
2178                    &n->bc_entry.named_rcv_nxt,
2179                    &n->bc_entry.named_open);
2180
2181     if (unlikely(!skb_queue_empty(&n->bc_entry.inputq1)))
2182         tipc_node_mcast_rcv(n);
2183
2184     if (!skb_queue_empty(&le->inputq))
2185         tipc_sk_rcv(net, &le->inputq);
2186
2187     if (!skb_queue_empty(&xmitq))
2188         tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr, n);
2189
2190 out_node_put:
2191     tipc_node_put(n);
2192 discard:
2193     kfree_skb(skb);
2194 }
2195
2196 void tipc_node_apply_property(struct net *net, struct tipc_bearer *b,
2197                   int prop)
2198 {
2199     struct tipc_net *tn = tipc_net(net);
2200     int bearer_id = b->identity;
2201     struct sk_buff_head xmitq;
2202     struct tipc_link_entry *e;
2203     struct tipc_node *n;
2204
2205     __skb_queue_head_init(&xmitq);
2206
2207     rcu_read_lock();
2208
2209     list_for_each_entry_rcu(n, &tn->node_list, list) {
2210         tipc_node_write_lock(n);
2211         e = &n->links[bearer_id];
2212         if (e->link) {
2213             if (prop == TIPC_NLA_PROP_TOL)
2214                 tipc_link_set_tolerance(e->link, b->tolerance,
2215                             &xmitq);
2216             else if (prop == TIPC_NLA_PROP_MTU)
2217                 tipc_link_set_mtu(e->link, b->mtu);
2218
2219             /* Update MTU for node link entry */
2220             e->mtu = tipc_link_mss(e->link);
2221         }
2222
2223         tipc_node_write_unlock(n);
2224         tipc_bearer_xmit(net, bearer_id, &xmitq, &e->maddr, NULL);
2225     }
2226
2227     rcu_read_unlock();
2228 }
2229
2230 int tipc_nl_peer_rm(struct sk_buff *skb, struct genl_info *info)
2231 {
2232     struct net *net = sock_net(skb->sk);
2233     struct tipc_net *tn = net_generic(net, tipc_net_id);
2234     struct nlattr *attrs[TIPC_NLA_NET_MAX + 1];
2235     struct tipc_node *peer, *temp_node;
2236     u8 node_id[NODE_ID_LEN];
2237     u64 *w0 = (u64 *)&node_id[0];
2238     u64 *w1 = (u64 *)&node_id[8];
2239     u32 addr;
2240     int err;
2241
2242     /* We identify the peer by its net */
2243     if (!info->attrs[TIPC_NLA_NET])
2244         return -EINVAL;
2245
2246     err = nla_parse_nested_deprecated(attrs, TIPC_NLA_NET_MAX,
2247                       info->attrs[TIPC_NLA_NET],
2248                       tipc_nl_net_policy, info->extack);
2249     if (err)
2250         return err;
2251
2252     /* attrs[TIPC_NLA_NET_NODEID] and attrs[TIPC_NLA_NET_ADDR] are
2253      * mutually exclusive cases
2254      */
2255     if (attrs[TIPC_NLA_NET_ADDR]) {
2256         addr = nla_get_u32(attrs[TIPC_NLA_NET_ADDR]);
2257         if (!addr)
2258             return -EINVAL;
2259     }
2260
2261     if (attrs[TIPC_NLA_NET_NODEID]) {
2262         if (!attrs[TIPC_NLA_NET_NODEID_W1])
2263             return -EINVAL;
2264         *w0 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID]);
2265         *w1 = nla_get_u64(attrs[TIPC_NLA_NET_NODEID_W1]);
2266         addr = hash128to32(node_id);
2267     }
2268
2269     if (in_own_node(net, addr))
2270         return -ENOTSUPP;
2271
2272     spin_lock_bh(&tn->node_list_lock);
2273     peer = tipc_node_find(net, addr);
2274     if (!peer) {
2275         spin_unlock_bh(&tn->node_list_lock);
2276         return -ENXIO;
2277     }
2278
2279     tipc_node_write_lock(peer);
2280     if (peer->state != SELF_DOWN_PEER_DOWN &&
2281         peer->state != SELF_DOWN_PEER_LEAVING) {
2282         tipc_node_write_unlock(peer);
2283         err = -EBUSY;
2284         goto err_out;
2285     }
2286
2287     tipc_node_clear_links(peer);
2288     tipc_node_write_unlock(peer);
2289     tipc_node_delete(peer);
2290
2291     /* Calculate cluster capabilities */
2292     tn->capabilities = TIPC_NODE_CAPABILITIES;
2293     list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
2294         tn->capabilities &= temp_node->capabilities;
2295     }
2296     tipc_bcast_toggle_rcast(net, (tn->capabilities & TIPC_BCAST_RCAST));
2297     err = 0;
2298 err_out:
2299     tipc_node_put(peer);
2300     spin_unlock_bh(&tn->node_list_lock);
2301
2302     return err;
2303 }
2304
2305 int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb)
2306 {
2307     int err;
2308     struct net *net = sock_net(skb->sk);
2309     struct tipc_net *tn = net_generic(net, tipc_net_id);
2310     int done = cb->args[0];
2311     int last_addr = cb->args[1];
2312     struct tipc_node *node;
2313     struct tipc_nl_msg msg;
2314
2315     if (done)
2316         return 0;
2317
2318     msg.skb = skb;
2319     msg.portid = NETLINK_CB(cb->skb).portid;
2320     msg.seq = cb->nlh->nlmsg_seq;
2321
2322     rcu_read_lock();
2323     if (last_addr) {
2324         node = tipc_node_find(net, last_addr);
2325         if (!node) {
2326             rcu_read_unlock();
2327             /* We never set seq or call nl_dump_check_consistent()
2328              * this means that setting prev_seq here will cause the
2329              * consistence check to fail in the netlink callback
2330              * handler. Resulting in the NLMSG_DONE message having
2331              * the NLM_F_DUMP_INTR flag set if the node state
2332              * changed while we released the lock.
2333              */
2334             cb->prev_seq = 1;
2335             return -EPIPE;
2336         }
2337         tipc_node_put(node);
2338     }
2339
2340     list_for_each_entry_rcu(node, &tn->node_list, list) {
2341         if (node->preliminary)
2342             continue;
2343         if (last_addr) {
2344             if (node->addr == last_addr)
2345                 last_addr = 0;
2346             else
2347                 continue;
2348         }
2349
2350         tipc_node_read_lock(node);
2351         err = __tipc_nl_add_node(&msg, node);
2352         if (err) {
2353             last_addr = node->addr;
2354             tipc_node_read_unlock(node);
2355             goto out;
2356         }
2357
2358         tipc_node_read_unlock(node);
2359     }
2360     done = 1;
2361 out:
2362     cb->args[0] = done;
2363     cb->args[1] = last_addr;
2364     rcu_read_unlock();
2365
2366     return skb->len;
2367 }
2368
2369 /* tipc_node_find_by_name - locate owner node of link by link's name
2370  * @net: the applicable net namespace
2371  * @name: pointer to link name string
2372  * @bearer_id: pointer to index in 'node->links' array where the link was found.
2373  *
2374  * Returns pointer to node owning the link, or 0 if no matching link is found.
2375  */
2376 static struct tipc_node *tipc_node_find_by_name(struct net *net,
2377                         const char *link_name,
2378                         unsigned int *bearer_id)
2379 {
2380     struct tipc_net *tn = net_generic(net, tipc_net_id);
2381     struct tipc_link *l;
2382     struct tipc_node *n;
2383     struct tipc_node *found_node = NULL;
2384     int i;
2385
2386     *bearer_id = 0;
2387     rcu_read_lock();
2388     list_for_each_entry_rcu(n, &tn->node_list, list) {
2389         tipc_node_read_lock(n);
2390         for (i = 0; i < MAX_BEARERS; i++) {
2391             l = n->links[i].link;
2392             if (l && !strcmp(tipc_link_name(l), link_name)) {
2393                 *bearer_id = i;
2394                 found_node = n;
2395                 break;
2396             }
2397         }
2398         tipc_node_read_unlock(n);
2399         if (found_node)
2400             break;
2401     }
2402     rcu_read_unlock();
2403
2404     return found_node;
2405 }
2406
2407 int tipc_nl_node_set_link(struct sk_buff *skb, struct genl_info *info)
2408 {
2409     int err;
2410     int res = 0;
2411     int bearer_id;
2412     char *name;
2413     struct tipc_link *link;
2414     struct tipc_node *node;
2415     struct sk_buff_head xmitq;
2416     struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2417     struct net *net = sock_net(skb->sk);
2418
2419     __skb_queue_head_init(&xmitq);
2420
2421     if (!info->attrs[TIPC_NLA_LINK])
2422         return -EINVAL;
2423
2424     err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2425                       info->attrs[TIPC_NLA_LINK],
2426                       tipc_nl_link_policy, info->extack);
2427     if (err)
2428         return err;
2429
2430     if (!attrs[TIPC_NLA_LINK_NAME])
2431         return -EINVAL;
2432
2433     name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2434
2435     if (strcmp(name, tipc_bclink_name) == 0)
2436         return tipc_nl_bc_link_set(net, attrs);
2437
2438     node = tipc_node_find_by_name(net, name, &bearer_id);
2439     if (!node)
2440         return -EINVAL;
2441
2442     tipc_node_read_lock(node);
2443
2444     link = node->links[bearer_id].link;
2445     if (!link) {
2446         res = -EINVAL;
2447         goto out;
2448     }
2449
2450     if (attrs[TIPC_NLA_LINK_PROP]) {
2451         struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
2452
2453         err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], props);
2454         if (err) {
2455             res = err;
2456             goto out;
2457         }
2458
2459         if (props[TIPC_NLA_PROP_TOL]) {
2460             u32 tol;
2461
2462             tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2463             tipc_link_set_tolerance(link, tol, &xmitq);
2464         }
2465         if (props[TIPC_NLA_PROP_PRIO]) {
2466             u32 prio;
2467
2468             prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2469             tipc_link_set_prio(link, prio, &xmitq);
2470         }
2471         if (props[TIPC_NLA_PROP_WIN]) {
2472             u32 max_win;
2473
2474             max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2475             tipc_link_set_queue_limits(link,
2476                            tipc_link_min_win(link),
2477                            max_win);
2478         }
2479     }
2480
2481 out:
2482     tipc_node_read_unlock(node);
2483     tipc_bearer_xmit(net, bearer_id, &xmitq, &node->links[bearer_id].maddr,
2484              NULL);
2485     return res;
2486 }
2487
2488 int tipc_nl_node_get_link(struct sk_buff *skb, struct genl_info *info)
2489 {
2490     struct net *net = genl_info_net(info);
2491     struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2492     struct tipc_nl_msg msg;
2493     char *name;
2494     int err;
2495
2496     msg.portid = info->snd_portid;
2497     msg.seq = info->snd_seq;
2498
2499     if (!info->attrs[TIPC_NLA_LINK])
2500         return -EINVAL;
2501
2502     err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2503                       info->attrs[TIPC_NLA_LINK],
2504                       tipc_nl_link_policy, info->extack);
2505     if (err)
2506         return err;
2507
2508     if (!attrs[TIPC_NLA_LINK_NAME])
2509         return -EINVAL;
2510
2511     name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2512
2513     msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2514     if (!msg.skb)
2515         return -ENOMEM;
2516
2517     if (strcmp(name, tipc_bclink_name) == 0) {
2518         err = tipc_nl_add_bc_link(net, &msg, tipc_net(net)->bcl);
2519         if (err)
2520             goto err_free;
2521     } else {
2522         int bearer_id;
2523         struct tipc_node *node;
2524         struct tipc_link *link;
2525
2526         node = tipc_node_find_by_name(net, name, &bearer_id);
2527         if (!node) {
2528             err = -EINVAL;
2529             goto err_free;
2530         }
2531
2532         tipc_node_read_lock(node);
2533         link = node->links[bearer_id].link;
2534         if (!link) {
2535             tipc_node_read_unlock(node);
2536             err = -EINVAL;
2537             goto err_free;
2538         }
2539
2540         err = __tipc_nl_add_link(net, &msg, link, 0);
2541         tipc_node_read_unlock(node);
2542         if (err)
2543             goto err_free;
2544     }
2545
2546     return genlmsg_reply(msg.skb, info);
2547
2548 err_free:
2549     nlmsg_free(msg.skb);
2550     return err;
2551 }
2552
2553 int tipc_nl_node_reset_link_stats(struct sk_buff *skb, struct genl_info *info)
2554 {
2555     int err;
2556     char *link_name;
2557     unsigned int bearer_id;
2558     struct tipc_link *link;
2559     struct tipc_node *node;
2560     struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2561     struct net *net = sock_net(skb->sk);
2562     struct tipc_net *tn = tipc_net(net);
2563     struct tipc_link_entry *le;
2564
2565     if (!info->attrs[TIPC_NLA_LINK])
2566         return -EINVAL;
2567
2568     err = nla_parse_nested_deprecated(attrs, TIPC_NLA_LINK_MAX,
2569                       info->attrs[TIPC_NLA_LINK],
2570                       tipc_nl_link_policy, info->extack);
2571     if (err)
2572         return err;
2573
2574     if (!attrs[TIPC_NLA_LINK_NAME])
2575         return -EINVAL;
2576
2577     link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2578
2579     err = -EINVAL;
2580     if (!strcmp(link_name, tipc_bclink_name)) {
2581         err = tipc_bclink_reset_stats(net, tipc_bc_sndlink(net));
2582         if (err)
2583             return err;
2584         return 0;
2585     } else if (strstr(link_name, tipc_bclink_name)) {
2586         rcu_read_lock();
2587         list_for_each_entry_rcu(node, &tn->node_list, list) {
2588             tipc_node_read_lock(node);
2589             link = node->bc_entry.link;
2590             if (link && !strcmp(link_name, tipc_link_name(link))) {
2591                 err = tipc_bclink_reset_stats(net, link);
2592                 tipc_node_read_unlock(node);
2593                 break;
2594             }
2595             tipc_node_read_unlock(node);
2596         }
2597         rcu_read_unlock();
2598         return err;
2599     }
2600
2601     node = tipc_node_find_by_name(net, link_name, &bearer_id);
2602     if (!node)
2603         return -EINVAL;
2604
2605     le = &node->links[bearer_id];
2606     tipc_node_read_lock(node);
2607     spin_lock_bh(&le->lock);
2608     link = node->links[bearer_id].link;
2609     if (!link) {
2610         spin_unlock_bh(&le->lock);
2611         tipc_node_read_unlock(node);
2612         return -EINVAL;
2613     }
2614     tipc_link_reset_stats(link);
2615     spin_unlock_bh(&le->lock);
2616     tipc_node_read_unlock(node);
2617     return 0;
2618 }
2619
2620 /* Caller should hold node lock  */
2621 static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
2622                     struct tipc_node *node, u32 *prev_link,
2623                     bool bc_link)
2624 {
2625     u32 i;
2626     int err;
2627
2628     for (i = *prev_link; i < MAX_BEARERS; i++) {
2629         *prev_link = i;
2630
2631         if (!node->links[i].link)
2632             continue;
2633
2634         err = __tipc_nl_add_link(net, msg,
2635                      node->links[i].link, NLM_F_MULTI);
2636         if (err)
2637             return err;
2638     }
2639
2640     if (bc_link) {
2641         *prev_link = i;
2642         err = tipc_nl_add_bc_link(net, msg, node->bc_entry.link);
2643         if (err)
2644             return err;
2645     }
2646
2647     *prev_link = 0;
2648
2649     return 0;
2650 }
2651
2652 int tipc_nl_node_dump_link(struct sk_buff *skb, struct netlink_callback *cb)
2653 {
2654     struct net *net = sock_net(skb->sk);
2655     struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
2656     struct nlattr *link[TIPC_NLA_LINK_MAX + 1];
2657     struct tipc_net *tn = net_generic(net, tipc_net_id);
2658     struct tipc_node *node;
2659     struct tipc_nl_msg msg;
2660     u32 prev_node = cb->args[0];
2661     u32 prev_link = cb->args[1];
2662     int done = cb->args[2];
2663     bool bc_link = cb->args[3];
2664     int err;
2665
2666     if (done)
2667         return 0;
2668
2669     if (!prev_node) {
2670         /* Check if broadcast-receiver links dumping is needed */
2671         if (attrs && attrs[TIPC_NLA_LINK]) {
2672             err = nla_parse_nested_deprecated(link,
2673                               TIPC_NLA_LINK_MAX,
2674                               attrs[TIPC_NLA_LINK],
2675                               tipc_nl_link_policy,
2676                               NULL);
2677             if (unlikely(err))
2678                 return err;
2679             if (unlikely(!link[TIPC_NLA_LINK_BROADCAST]))
2680                 return -EINVAL;
2681             bc_link = true;
2682         }
2683     }
2684
2685     msg.skb = skb;
2686     msg.portid = NETLINK_CB(cb->skb).portid;
2687     msg.seq = cb->nlh->nlmsg_seq;
2688
2689     rcu_read_lock();
2690     if (prev_node) {
2691         node = tipc_node_find(net, prev_node);
2692         if (!node) {
2693             /* We never set seq or call nl_dump_check_consistent()
2694              * this means that setting prev_seq here will cause the
2695              * consistence check to fail in the netlink callback
2696              * handler. Resulting in the last NLMSG_DONE message
2697              * having the NLM_F_DUMP_INTR flag set.
2698              */
2699             cb->prev_seq = 1;
2700             goto out;
2701         }
2702         tipc_node_put(node);
2703
2704         list_for_each_entry_continue_rcu(node, &tn->node_list,
2705                          list) {
2706             tipc_node_read_lock(node);
2707             err = __tipc_nl_add_node_links(net, &msg, node,
2708                                &prev_link, bc_link);
2709             tipc_node_read_unlock(node);
2710             if (err)
2711                 goto out;
2712
2713             prev_node = node->addr;
2714         }
2715     } else {
2716         err = tipc_nl_add_bc_link(net, &msg, tn->bcl);
2717         if (err)
2718             goto out;
2719
2720         list_for_each_entry_rcu(node, &tn->node_list, list) {
2721             tipc_node_read_lock(node);
2722             err = __tipc_nl_add_node_links(net, &msg, node,
2723                                &prev_link, bc_link);
2724             tipc_node_read_unlock(node);
2725             if (err)
2726                 goto out;
2727
2728             prev_node = node->addr;
2729         }
2730     }
2731     done = 1;
2732 out:
2733     rcu_read_unlock();
2734
2735     cb->args[0] = prev_node;
2736     cb->args[1] = prev_link;
2737     cb->args[2] = done;
2738     cb->args[3] = bc_link;
2739
2740     return skb->len;
2741 }
2742
2743 int tipc_nl_node_set_monitor(struct sk_buff *skb, struct genl_info *info)
2744 {
2745     struct nlattr *attrs[TIPC_NLA_MON_MAX + 1];
2746     struct net *net = sock_net(skb->sk);
2747     int err;
2748
2749     if (!info->attrs[TIPC_NLA_MON])
2750         return -EINVAL;
2751
2752     err = nla_parse_nested_deprecated(attrs, TIPC_NLA_MON_MAX,
2753                       info->attrs[TIPC_NLA_MON],
2754                       tipc_nl_monitor_policy,
2755                       info->extack);
2756     if (err)
2757         return err;
2758
2759     if (attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]) {
2760         u32 val;
2761
2762         val = nla_get_u32(attrs[TIPC_NLA_MON_ACTIVATION_THRESHOLD]);
2763         err = tipc_nl_monitor_set_threshold(net, val);
2764         if (err)
2765             return err;
2766     }
2767
2768     return 0;
2769 }
2770
2771 static int __tipc_nl_add_monitor_prop(struct net *net, struct tipc_nl_msg *msg)
2772 {
2773     struct nlattr *attrs;
2774     void *hdr;
2775     u32 val;
2776
2777     hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2778               0, TIPC_NL_MON_GET);
2779     if (!hdr)
2780         return -EMSGSIZE;
2781
2782     attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_MON);
2783     if (!attrs)
2784         goto msg_full;
2785
2786     val = tipc_nl_monitor_get_threshold(net);
2787
2788     if (nla_put_u32(msg->skb, TIPC_NLA_MON_ACTIVATION_THRESHOLD, val))
2789         goto attr_msg_full;
2790
2791     nla_nest_end(msg->skb, attrs);
2792     genlmsg_end(msg->skb, hdr);
2793
2794     return 0;
2795
2796 attr_msg_full:
2797     nla_nest_cancel(msg->skb, attrs);
2798 msg_full:
2799     genlmsg_cancel(msg->skb, hdr);
2800
2801     return -EMSGSIZE;
2802 }
2803
2804 int tipc_nl_node_get_monitor(struct sk_buff *skb, struct genl_info *info)
2805 {
2806     struct net *net = sock_net(skb->sk);
2807     struct tipc_nl_msg msg;
2808     int err;
2809
2810     msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2811     if (!msg.skb)
2812         return -ENOMEM;
2813     msg.portid = info->snd_portid;
2814     msg.seq = info->snd_seq;
2815
2816     err = __tipc_nl_add_monitor_prop(net, &msg);
2817     if (err) {
2818         nlmsg_free(msg.skb);
2819         return err;
2820     }
2821
2822     return genlmsg_reply(msg.skb, info);
2823 }
2824
2825 int tipc_nl_node_dump_monitor(struct sk_buff *skb, struct netlink_callback *cb)
2826 {
2827     struct net *net = sock_net(skb->sk);
2828     u32 prev_bearer = cb->args[0];
2829     struct tipc_nl_msg msg;
2830     int bearer_id;
2831     int err;
2832
2833     if (prev_bearer == MAX_BEARERS)
2834         return 0;
2835
2836     msg.skb = skb;
2837     msg.portid = NETLINK_CB(cb->skb).portid;
2838     msg.seq = cb->nlh->nlmsg_seq;
2839
2840     rtnl_lock();
2841     for (bearer_id = prev_bearer; bearer_id < MAX_BEARERS; bearer_id++) {
2842         err = __tipc_nl_add_monitor(net, &msg, bearer_id);
2843         if (err)
2844             break;
2845     }
2846     rtnl_unlock();
2847     cb->args[0] = bearer_id;
2848
2849     return skb->len;
2850 }
2851
2852 int tipc_nl_node_dump_monitor_peer(struct sk_buff *skb,
2853                    struct netlink_callback *cb)
2854 {
2855     struct net *net = sock_net(skb->sk);
2856     u32 prev_node = cb->args[1];
2857     u32 bearer_id = cb->args[2];
2858     int done = cb->args[0];
2859     struct tipc_nl_msg msg;
2860     int err;
2861
2862     if (!prev_node) {
2863         struct nlattr **attrs = genl_dumpit_info(cb)->attrs;
2864         struct nlattr *mon[TIPC_NLA_MON_MAX + 1];
2865
2866         if (!attrs[TIPC_NLA_MON])
2867             return -EINVAL;
2868
2869         err = nla_parse_nested_deprecated(mon, TIPC_NLA_MON_MAX,
2870                           attrs[TIPC_NLA_MON],
2871                           tipc_nl_monitor_policy,
2872                           NULL);
2873         if (err)
2874             return err;
2875
2876         if (!mon[TIPC_NLA_MON_REF])
2877             return -EINVAL;
2878
2879         bearer_id = nla_get_u32(mon[TIPC_NLA_MON_REF]);
2880
2881         if (bearer_id >= MAX_BEARERS)
2882             return -EINVAL;
2883     }
2884
2885     if (done)
2886         return 0;
2887
2888     msg.skb = skb;
2889     msg.portid = NETLINK_CB(cb->skb).portid;
2890     msg.seq = cb->nlh->nlmsg_seq;
2891
2892     rtnl_lock();
2893     err = tipc_nl_add_monitor_peer(net, &msg, bearer_id, &prev_node);
2894     if (!err)
2895         done = 1;
2896
2897     rtnl_unlock();
2898     cb->args[0] = done;
2899     cb->args[1] = prev_node;
2900     cb->args[2] = bearer_id;
2901
2902     return skb->len;
2903 }
2904
2905 #ifdef CONFIG_TIPC_CRYPTO
2906 static int tipc_nl_retrieve_key(struct nlattr **attrs,
2907                 struct tipc_aead_key **pkey)
2908 {
2909     struct nlattr *attr = attrs[TIPC_NLA_NODE_KEY];
2910     struct tipc_aead_key *key;
2911
2912     if (!attr)
2913         return -ENODATA;
2914
2915     if (nla_len(attr) < sizeof(*key))
2916         return -EINVAL;
2917     key = (struct tipc_aead_key *)nla_data(attr);
2918     if (key->keylen > TIPC_AEAD_KEYLEN_MAX ||
2919         nla_len(attr) < tipc_aead_key_size(key))
2920         return -EINVAL;
2921
2922     *pkey = key;
2923     return 0;
2924 }
2925
2926 static int tipc_nl_retrieve_nodeid(struct nlattr **attrs, u8 **node_id)
2927 {
2928     struct nlattr *attr = attrs[TIPC_NLA_NODE_ID];
2929
2930     if (!attr)
2931         return -ENODATA;
2932
2933     if (nla_len(attr) < TIPC_NODEID_LEN)
2934         return -EINVAL;
2935
2936     *node_id = (u8 *)nla_data(attr);
2937     return 0;
2938 }
2939
2940 static int tipc_nl_retrieve_rekeying(struct nlattr **attrs, u32 *intv)
2941 {
2942     struct nlattr *attr = attrs[TIPC_NLA_NODE_REKEYING];
2943
2944     if (!attr)
2945         return -ENODATA;
2946
2947     *intv = nla_get_u32(attr);
2948     return 0;
2949 }
2950
2951 static int __tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
2952 {
2953     struct nlattr *attrs[TIPC_NLA_NODE_MAX + 1];
2954     struct net *net = sock_net(skb->sk);
2955     struct tipc_crypto *tx = tipc_net(net)->crypto_tx, *c = tx;
2956     struct tipc_node *n = NULL;
2957     struct tipc_aead_key *ukey;
2958     bool rekeying = true, master_key = false;
2959     u8 *id, *own_id, mode;
2960     u32 intv = 0;
2961     int rc = 0;
2962
2963     if (!info->attrs[TIPC_NLA_NODE])
2964         return -EINVAL;
2965
2966     rc = nla_parse_nested(attrs, TIPC_NLA_NODE_MAX,
2967                   info->attrs[TIPC_NLA_NODE],
2968                   tipc_nl_node_policy, info->extack);
2969     if (rc)
2970         return rc;
2971
2972     own_id = tipc_own_id(net);
2973     if (!own_id) {
2974         GENL_SET_ERR_MSG(info, "not found own node identity (set id?)");
2975         return -EPERM;
2976     }
2977
2978     rc = tipc_nl_retrieve_rekeying(attrs, &intv);
2979     if (rc == -ENODATA)
2980         rekeying = false;
2981
2982     rc = tipc_nl_retrieve_key(attrs, &ukey);
2983     if (rc == -ENODATA && rekeying)
2984         goto rekeying;
2985     else if (rc)
2986         return rc;
2987
2988     rc = tipc_aead_key_validate(ukey, info);
2989     if (rc)
2990         return rc;
2991
2992     rc = tipc_nl_retrieve_nodeid(attrs, &id);
2993     switch (rc) {
2994     case -ENODATA:
2995         mode = CLUSTER_KEY;
2996         master_key = !!(attrs[TIPC_NLA_NODE_KEY_MASTER]);
2997         break;
2998     case 0:
2999         mode = PER_NODE_KEY;
3000         if (memcmp(id, own_id, NODE_ID_LEN)) {
3001             n = tipc_node_find_by_id(net, id) ?:
3002                 tipc_node_create(net, 0, id, 0xffffu, 0, true);
3003             if (unlikely(!n))
3004                 return -ENOMEM;
3005             c = n->crypto_rx;
3006         }
3007         break;
3008     default:
3009         return rc;
3010     }
3011
3012     /* Initiate the TX/RX key */
3013     rc = tipc_crypto_key_init(c, ukey, mode, master_key);
3014     if (n)
3015         tipc_node_put(n);
3016
3017     if (unlikely(rc < 0)) {
3018         GENL_SET_ERR_MSG(info, "unable to initiate or attach new key");
3019         return rc;
3020     } else if (c == tx) {
3021         /* Distribute TX key but not master one */
3022         if (!master_key && tipc_crypto_key_distr(tx, rc, NULL))
3023             GENL_SET_ERR_MSG(info, "failed to replicate new key");
3024 rekeying:
3025         /* Schedule TX rekeying if needed */
3026         tipc_crypto_rekeying_sched(tx, rekeying, intv);
3027     }
3028
3029     return 0;
3030 }
3031
3032 int tipc_nl_node_set_key(struct sk_buff *skb, struct genl_info *info)
3033 {
3034     int err;
3035
3036     rtnl_lock();
3037     err = __tipc_nl_node_set_key(skb, info);
3038     rtnl_unlock();
3039
3040     return err;
3041 }
3042
3043 static int __tipc_nl_node_flush_key(struct sk_buff *skb,
3044                     struct genl_info *info)
3045 {
3046     struct net *net = sock_net(skb->sk);
3047     struct tipc_net *tn = tipc_net(net);
3048     struct tipc_node *n;
3049
3050     tipc_crypto_key_flush(tn->crypto_tx);
3051     rcu_read_lock();
3052     list_for_each_entry_rcu(n, &tn->node_list, list)
3053         tipc_crypto_key_flush(n->crypto_rx);
3054     rcu_read_unlock();
3055
3056     return 0;
3057 }
3058
3059 int tipc_nl_node_flush_key(struct sk_buff *skb, struct genl_info *info)
3060 {
3061     int err;
3062
3063     rtnl_lock();
3064     err = __tipc_nl_node_flush_key(skb, info);
3065     rtnl_unlock();
3066
3067     return err;
3068 }
3069 #endif
3070
3071 /**
3072  * tipc_node_dump - dump TIPC node data
3073  * @n: tipc node to be dumped
3074  * @more: dump more?
3075  *        - false: dump only tipc node data
3076  *        - true: dump node link data as well
3077  * @buf: returned buffer of dump data in format
3078  */
3079 int tipc_node_dump(struct tipc_node *n, bool more, char *buf)
3080 {
3081     int i = 0;
3082     size_t sz = (more) ? NODE_LMAX : NODE_LMIN;
3083
3084     if (!n) {
3085         i += scnprintf(buf, sz, "node data: (null)\n");
3086         return i;
3087     }
3088
3089     i += scnprintf(buf, sz, "node data: %x", n->addr);
3090     i += scnprintf(buf + i, sz - i, " %x", n->state);
3091     i += scnprintf(buf + i, sz - i, " %d", n->active_links[0]);
3092     i += scnprintf(buf + i, sz - i, " %d", n->active_links[1]);
3093     i += scnprintf(buf + i, sz - i, " %x", n->action_flags);
3094     i += scnprintf(buf + i, sz - i, " %u", n->failover_sent);
3095     i += scnprintf(buf + i, sz - i, " %u", n->sync_point);
3096     i += scnprintf(buf + i, sz - i, " %d", n->link_cnt);
3097     i += scnprintf(buf + i, sz - i, " %u", n->working_links);
3098     i += scnprintf(buf + i, sz - i, " %x", n->capabilities);
3099     i += scnprintf(buf + i, sz - i, " %lu\n", n->keepalive_intv);
3100
3101     if (!more)
3102         return i;
3103
3104     i += scnprintf(buf + i, sz - i, "link_entry[0]:\n");
3105     i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[0].mtu);
3106     i += scnprintf(buf + i, sz - i, " media: ");
3107     i += tipc_media_addr_printf(buf + i, sz - i, &n->links[0].maddr);
3108     i += scnprintf(buf + i, sz - i, "\n");
3109     i += tipc_link_dump(n->links[0].link, TIPC_DUMP_NONE, buf + i);
3110     i += scnprintf(buf + i, sz - i, " inputq: ");
3111     i += tipc_list_dump(&n->links[0].inputq, false, buf + i);
3112
3113     i += scnprintf(buf + i, sz - i, "link_entry[1]:\n");
3114     i += scnprintf(buf + i, sz - i, " mtu: %u\n", n->links[1].mtu);
3115     i += scnprintf(buf + i, sz - i, " media: ");
3116     i += tipc_media_addr_printf(buf + i, sz - i, &n->links[1].maddr);
3117     i += scnprintf(buf + i, sz - i, "\n");
3118     i += tipc_link_dump(n->links[1].link, TIPC_DUMP_NONE, buf + i);
3119     i += scnprintf(buf + i, sz - i, " inputq: ");
3120     i += tipc_list_dump(&n->links[1].inputq, false, buf + i);
3121
3122     i += scnprintf(buf + i, sz - i, "bclink:\n ");
3123     i += tipc_link_dump(n->bc_entry.link, TIPC_DUMP_NONE, buf + i);
3124
3125     return i;
3126 }
3127
3128 void tipc_node_pre_cleanup_net(struct net *exit_net)
3129 {
3130     struct tipc_node *n;
3131     struct tipc_net *tn;
3132     struct net *tmp;
3133
3134     rcu_read_lock();
3135     for_each_net_rcu(tmp) {
3136         if (tmp == exit_net)
3137             continue;
3138         tn = tipc_net(tmp);
3139         if (!tn)
3140             continue;
3141         spin_lock_bh(&tn->node_list_lock);
3142         list_for_each_entry_rcu(n, &tn->node_list, list) {
3143             if (!n->peer_net)
3144                 continue;
3145             if (n->peer_net != exit_net)
3146                 continue;
3147             tipc_node_write_lock(n);
3148             n->peer_net = NULL;
3149             n->peer_hash_mix = 0;
3150             tipc_node_write_unlock_fast(n);
3151             break;
3152         }
3153         spin_unlock_bh(&tn->node_list_lock);
3154     }
3155     rcu_read_unlock();
3156 }