1 files changed, 621 insertions, 0 deletions

diff --git a/net/tipc/node.c b/net/tipc/node.c
new file mode 100644
index 000000000..22c059ad2
--- /dev/null
+++ b/net/tipc/node.c
@@ -0,0 +1,621 @@
+/*
+ * net/tipc/node.c: TIPC node management routines
+ *
+ * Copyright (c) 2000-2006, 2012-2014, Ericsson AB
+ * Copyright (c) 2005-2006, 2010-2014, Wind River Systems
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "core.h"
+#include "link.h"
+#include "node.h"
+#include "name_distr.h"
+#include "socket.h"
+
+static void node_lost_contact(struct tipc_node *n_ptr);
+static void node_established_contact(struct tipc_node *n_ptr);
+static void tipc_node_delete(struct tipc_node *node);
+
+struct tipc_sock_conn {
+	u32 port;
+	u32 peer_port;
+	u32 peer_node;
+	struct list_head list;
+};
+
+static const struct nla_policy tipc_nl_node_policy[TIPC_NLA_NODE_MAX + 1] = {
+	[TIPC_NLA_NODE_UNSPEC]		= { .type = NLA_UNSPEC },
+	[TIPC_NLA_NODE_ADDR]		= { .type = NLA_U32 },
+	[TIPC_NLA_NODE_UP]		= { .type = NLA_FLAG }
+};
+
+/*
+ * A trivial power-of-two bitmask technique is used for speed, since this
+ * operation is done for every incoming TIPC packet. The number of hash table
+ * entries has been chosen so that no hash chain exceeds 8 nodes and will
+ * usually be much smaller (typically only a single node).
+ */
+static unsigned int tipc_hashfn(u32 addr)
+{
+	return addr & (NODE_HTABLE_SIZE - 1);
+}
+
+static void tipc_node_kref_release(struct kref *kref)
+{
+	struct tipc_node *node = container_of(kref, struct tipc_node, kref);
+
+	tipc_node_delete(node);
+}
+
+void tipc_node_put(struct tipc_node *node)
+{
+	kref_put(&node->kref, tipc_node_kref_release);
+}
+
+static void tipc_node_get(struct tipc_node *node)
+{
+	kref_get(&node->kref);
+}
+
+/*
+ * tipc_node_find - locate specified node object, if it exists
+ */
+struct tipc_node *tipc_node_find(struct net *net, u32 addr)
+{
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_node *node;
+
+	if (unlikely(!in_own_cluster_exact(net, addr)))
+		return NULL;
+
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(node, &tn->node_htable[tipc_hashfn(addr)],
+				 hash) {
+		if (node->addr == addr) {
+			tipc_node_get(node);
+			rcu_read_unlock();
+			return node;
+		}
+	}
+	rcu_read_unlock();
+	return NULL;
+}
+
+struct tipc_node *tipc_node_create(struct net *net, u32 addr)
+{
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_node *n_ptr, *temp_node;
+
+	spin_lock_bh(&tn->node_list_lock);
+	n_ptr = tipc_node_find(net, addr);
+	if (n_ptr)
+		goto exit;
+	n_ptr = kzalloc(sizeof(*n_ptr), GFP_ATOMIC);
+	if (!n_ptr) {
+		pr_warn("Node creation failed, no memory\n");
+		goto exit;
+	}
+	n_ptr->addr = addr;
+	n_ptr->net = net;
+	kref_init(&n_ptr->kref);
+	spin_lock_init(&n_ptr->lock);
+	INIT_HLIST_NODE(&n_ptr->hash);
+	INIT_LIST_HEAD(&n_ptr->list);
+	INIT_LIST_HEAD(&n_ptr->publ_list);
+	INIT_LIST_HEAD(&n_ptr->conn_sks);
+	__skb_queue_head_init(&n_ptr->bclink.deferdq);
+	hlist_add_head_rcu(&n_ptr->hash, &tn->node_htable[tipc_hashfn(addr)]);
+	list_for_each_entry_rcu(temp_node, &tn->node_list, list) {
+		if (n_ptr->addr < temp_node->addr)
+			break;
+	}
+	list_add_tail_rcu(&n_ptr->list, &temp_node->list);
+	n_ptr->action_flags = TIPC_WAIT_PEER_LINKS_DOWN;
+	n_ptr->signature = INVALID_NODE_SIG;
+	tipc_node_get(n_ptr);
+exit:
+	spin_unlock_bh(&tn->node_list_lock);
+	return n_ptr;
+}
+
+static void tipc_node_delete(struct tipc_node *node)
+{
+	list_del_rcu(&node->list);
+	hlist_del_rcu(&node->hash);
+	kfree_rcu(node, rcu);
+}
+
+void tipc_node_stop(struct net *net)
+{
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_node *node, *t_node;
+
+	spin_lock_bh(&tn->node_list_lock);
+	list_for_each_entry_safe(node, t_node, &tn->node_list, list)
+		tipc_node_put(node);
+	spin_unlock_bh(&tn->node_list_lock);
+}
+
+int tipc_node_add_conn(struct net *net, u32 dnode, u32 port, u32 peer_port)
+{
+	struct tipc_node *node;
+	struct tipc_sock_conn *conn;
+	int err = 0;
+
+	if (in_own_node(net, dnode))
+		return 0;
+
+	node = tipc_node_find(net, dnode);
+	if (!node) {
+		pr_warn("Connecting sock to node 0x%x failed\n", dnode);
+		return -EHOSTUNREACH;
+	}
+	conn = kmalloc(sizeof(*conn), GFP_ATOMIC);
+	if (!conn) {
+		err = -EHOSTUNREACH;
+		goto exit;
+	}
+	conn->peer_node = dnode;
+	conn->port = port;
+	conn->peer_port = peer_port;
+
+	tipc_node_lock(node);
+	list_add_tail(&conn->list, &node->conn_sks);
+	tipc_node_unlock(node);
+exit:
+	tipc_node_put(node);
+	return err;
+}
+
+void tipc_node_remove_conn(struct net *net, u32 dnode, u32 port)
+{
+	struct tipc_node *node;
+	struct tipc_sock_conn *conn, *safe;
+
+	if (in_own_node(net, dnode))
+		return;
+
+	node = tipc_node_find(net, dnode);
+	if (!node)
+		return;
+
+	tipc_node_lock(node);
+	list_for_each_entry_safe(conn, safe, &node->conn_sks, list) {
+		if (port != conn->port)
+			continue;
+		list_del(&conn->list);
+		kfree(conn);
+	}
+	tipc_node_unlock(node);
+	tipc_node_put(node);
+}
+
+/**
+ * tipc_node_link_up - handle addition of link
+ *
+ * Link becomes active (alone or shared) or standby, depending on its priority.
+ */
+void tipc_node_link_up(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
+{
+	struct tipc_link **active = &n_ptr->active_links[0];
+
+	n_ptr->working_links++;
+	n_ptr->action_flags |= TIPC_NOTIFY_LINK_UP;
+	n_ptr->link_id = l_ptr->peer_bearer_id << 16 | l_ptr->bearer_id;
+
+	pr_debug("Established link <%s> on network plane %c\n",
+		 l_ptr->name, l_ptr->net_plane);
+
+	if (!active[0]) {
+		active[0] = active[1] = l_ptr;
+		node_established_contact(n_ptr);
+		goto exit;
+	}
+	if (l_ptr->priority < active[0]->priority) {
+		pr_debug("New link <%s> becomes standby\n", l_ptr->name);
+		goto exit;
+	}
+	tipc_link_dup_queue_xmit(active[0], l_ptr);
+	if (l_ptr->priority == active[0]->priority) {
+		active[0] = l_ptr;
+		goto exit;
+	}
+	pr_debug("Old link <%s> becomes standby\n", active[0]->name);
+	if (active[1] != active[0])
+		pr_debug("Old link <%s> becomes standby\n", active[1]->name);
+	active[0] = active[1] = l_ptr;
+exit:
+	/* Leave room for changeover header when returning 'mtu' to users: */
+	n_ptr->act_mtus[0] = active[0]->mtu - INT_H_SIZE;
+	n_ptr->act_mtus[1] = active[1]->mtu - INT_H_SIZE;
+}
+
+/**
+ * node_select_active_links - select active link
+ */
+static void node_select_active_links(struct tipc_node *n_ptr)
+{
+	struct tipc_link **active = &n_ptr->active_links[0];
+	u32 i;
+	u32 highest_prio = 0;
+
+	active[0] = active[1] = NULL;
+
+	for (i = 0; i < MAX_BEARERS; i++) {
+		struct tipc_link *l_ptr = n_ptr->links[i];
+
+		if (!l_ptr || !tipc_link_is_up(l_ptr) ||
+		    (l_ptr->priority < highest_prio))
+			continue;
+
+		if (l_ptr->priority > highest_prio) {
+			highest_prio = l_ptr->priority;
+			active[0] = active[1] = l_ptr;
+		} else {
+			active[1] = l_ptr;
+		}
+	}
+}
+
+/**
+ * tipc_node_link_down - handle loss of link
+ */
+void tipc_node_link_down(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
+{
+	struct tipc_net *tn = net_generic(n_ptr->net, tipc_net_id);
+	struct tipc_link **active;
+
+	n_ptr->working_links--;
+	n_ptr->action_flags |= TIPC_NOTIFY_LINK_DOWN;
+	n_ptr->link_id = l_ptr->peer_bearer_id << 16 | l_ptr->bearer_id;
+
+	if (!tipc_link_is_active(l_ptr)) {
+		pr_debug("Lost standby link <%s> on network plane %c\n",
+			 l_ptr->name, l_ptr->net_plane);
+		return;
+	}
+	pr_debug("Lost link <%s> on network plane %c\n",
+		 l_ptr->name, l_ptr->net_plane);
+
+	active = &n_ptr->active_links[0];
+	if (active[0] == l_ptr)
+		active[0] = active[1];
+	if (active[1] == l_ptr)
+		active[1] = active[0];
+	if (active[0] == l_ptr)
+		node_select_active_links(n_ptr);
+	if (tipc_node_is_up(n_ptr))
+		tipc_link_failover_send_queue(l_ptr);
+	else
+		node_lost_contact(n_ptr);
+
+	/* Leave room for changeover header when returning 'mtu' to users: */
+	if (active[0]) {
+		n_ptr->act_mtus[0] = active[0]->mtu - INT_H_SIZE;
+		n_ptr->act_mtus[1] = active[1]->mtu - INT_H_SIZE;
+		return;
+	}
+	/* Loopback link went down? No fragmentation needed from now on. */
+	if (n_ptr->addr == tn->own_addr) {
+		n_ptr->act_mtus[0] = MAX_MSG_SIZE;
+		n_ptr->act_mtus[1] = MAX_MSG_SIZE;
+	}
+}
+
+int tipc_node_active_links(struct tipc_node *n_ptr)
+{
+	return n_ptr->active_links[0] != NULL;
+}
+
+int tipc_node_is_up(struct tipc_node *n_ptr)
+{
+	return tipc_node_active_links(n_ptr);
+}
+
+void tipc_node_attach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
+{
+	n_ptr->links[l_ptr->bearer_id] = l_ptr;
+	n_ptr->link_cnt++;
+}
+
+void tipc_node_detach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr)
+{
+	int i;
+
+	for (i = 0; i < MAX_BEARERS; i++) {
+		if (l_ptr != n_ptr->links[i])
+			continue;
+		n_ptr->links[i] = NULL;
+		n_ptr->link_cnt--;
+	}
+}
+
+static void node_established_contact(struct tipc_node *n_ptr)
+{
+	n_ptr->action_flags |= TIPC_NOTIFY_NODE_UP;
+	n_ptr->bclink.oos_state = 0;
+	n_ptr->bclink.acked = tipc_bclink_get_last_sent(n_ptr->net);
+	tipc_bclink_add_node(n_ptr->net, n_ptr->addr);
+}
+
+static void node_lost_contact(struct tipc_node *n_ptr)
+{
+	char addr_string[16];
+	struct tipc_sock_conn *conn, *safe;
+	struct list_head *conns = &n_ptr->conn_sks;
+	struct sk_buff *skb;
+	struct tipc_net *tn = net_generic(n_ptr->net, tipc_net_id);
+	uint i;
+
+	pr_debug("Lost contact with %s\n",
+		 tipc_addr_string_fill(addr_string, n_ptr->addr));
+
+	/* Flush broadcast link info associated with lost node */
+	if (n_ptr->bclink.recv_permitted) {
+		__skb_queue_purge(&n_ptr->bclink.deferdq);
+
+		if (n_ptr->bclink.reasm_buf) {
+			kfree_skb(n_ptr->bclink.reasm_buf);
+			n_ptr->bclink.reasm_buf = NULL;
+		}
+
+		tipc_bclink_remove_node(n_ptr->net, n_ptr->addr);
+		tipc_bclink_acknowledge(n_ptr, INVALID_LINK_SEQ);
+
+		n_ptr->bclink.recv_permitted = false;
+	}
+
+	/* Abort any ongoing link failover */
+	for (i = 0; i < MAX_BEARERS; i++) {
+		struct tipc_link *l_ptr = n_ptr->links[i];
+		if (!l_ptr)
+			continue;
+		l_ptr->flags &= ~LINK_FAILINGOVER;
+		l_ptr->failover_checkpt = 0;
+		l_ptr->failover_pkts = 0;
+		kfree_skb(l_ptr->failover_skb);
+		l_ptr->failover_skb = NULL;
+		tipc_link_reset_fragments(l_ptr);
+	}
+
+	n_ptr->action_flags &= ~TIPC_WAIT_OWN_LINKS_DOWN;
+
+	/* Prevent re-contact with node until cleanup is done */
+	n_ptr->action_flags |= TIPC_WAIT_PEER_LINKS_DOWN;
+
+	/* Notify publications from this node */
+	n_ptr->action_flags |= TIPC_NOTIFY_NODE_DOWN;
+
+	/* Notify sockets connected to node */
+	list_for_each_entry_safe(conn, safe, conns, list) {
+		skb = tipc_msg_create(TIPC_CRITICAL_IMPORTANCE, TIPC_CONN_MSG,
+				      SHORT_H_SIZE, 0, tn->own_addr,
+				      conn->peer_node, conn->port,
+				      conn->peer_port, TIPC_ERR_NO_NODE);
+		if (likely(skb)) {
+			skb_queue_tail(n_ptr->inputq, skb);
+			n_ptr->action_flags |= TIPC_MSG_EVT;
+		}
+		list_del(&conn->list);
+		kfree(conn);
+	}
+}
+
+/**
+ * tipc_node_get_linkname - get the name of a link
+ *
+ * @bearer_id: id of the bearer
+ * @node: peer node address
+ * @linkname: link name output buffer
+ *
+ * Returns 0 on success
+ */
+int tipc_node_get_linkname(struct net *net, u32 bearer_id, u32 addr,
+			   char *linkname, size_t len)
+{
+	struct tipc_link *link;
+	int err = -EINVAL;
+	struct tipc_node *node = tipc_node_find(net, addr);
+
+	if (!node)
+		return err;
+
+	if (bearer_id >= MAX_BEARERS)
+		goto exit;
+
+	tipc_node_lock(node);
+	link = node->links[bearer_id];
+	if (link) {
+		strncpy(linkname, link->name, len);
+		err = 0;
+	}
+exit:
+	tipc_node_unlock(node);
+	tipc_node_put(node);
+	return err;
+}
+
+void tipc_node_unlock(struct tipc_node *node)
+{
+	struct net *net = node->net;
+	u32 addr = 0;
+	u32 flags = node->action_flags;
+	u32 link_id = 0;
+	struct list_head *publ_list;
+	struct sk_buff_head *inputq = node->inputq;
+	struct sk_buff_head *namedq;
+
+	if (likely(!flags || (flags == TIPC_MSG_EVT))) {
+		node->action_flags = 0;
+		spin_unlock_bh(&node->lock);
+		if (flags == TIPC_MSG_EVT)
+			tipc_sk_rcv(net, inputq);
+		return;
+	}
+
+	addr = node->addr;
+	link_id = node->link_id;
+	namedq = node->namedq;
+	publ_list = &node->publ_list;
+
+	node->action_flags &= ~(TIPC_MSG_EVT |
+				TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP |
+				TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP |
+				TIPC_WAKEUP_BCAST_USERS | TIPC_BCAST_MSG_EVT |
+				TIPC_NAMED_MSG_EVT | TIPC_BCAST_RESET);
+
+	spin_unlock_bh(&node->lock);
+
+	if (flags & TIPC_NOTIFY_NODE_DOWN)
+		tipc_publ_notify(net, publ_list, addr);
+
+	if (flags & TIPC_WAKEUP_BCAST_USERS)
+		tipc_bclink_wakeup_users(net);
+
+	if (flags & TIPC_NOTIFY_NODE_UP)
+		tipc_named_node_up(net, addr);
+
+	if (flags & TIPC_NOTIFY_LINK_UP)
+		tipc_nametbl_publish(net, TIPC_LINK_STATE, addr, addr,
+				     TIPC_NODE_SCOPE, link_id, addr);
+
+	if (flags & TIPC_NOTIFY_LINK_DOWN)
+		tipc_nametbl_withdraw(net, TIPC_LINK_STATE, addr,
+				      link_id, addr);
+
+	if (flags & TIPC_MSG_EVT)
+		tipc_sk_rcv(net, inputq);
+
+	if (flags & TIPC_NAMED_MSG_EVT)
+		tipc_named_rcv(net, namedq);
+
+	if (flags & TIPC_BCAST_MSG_EVT)
+		tipc_bclink_input(net);
+
+	if (flags & TIPC_BCAST_RESET)
+		tipc_link_reset_all(node);
+}
+
+/* Caller should hold node lock for the passed node */
+static int __tipc_nl_add_node(struct tipc_nl_msg *msg, struct tipc_node *node)
+{
+	void *hdr;
+	struct nlattr *attrs;
+
+	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
+			  NLM_F_MULTI, TIPC_NL_NODE_GET);
+	if (!hdr)
+		return -EMSGSIZE;
+
+	attrs = nla_nest_start(msg->skb, TIPC_NLA_NODE);
+	if (!attrs)
+		goto msg_full;
+
+	if (nla_put_u32(msg->skb, TIPC_NLA_NODE_ADDR, node->addr))
+		goto attr_msg_full;
+	if (tipc_node_is_up(node))
+		if (nla_put_flag(msg->skb, TIPC_NLA_NODE_UP))
+			goto attr_msg_full;
+
+	nla_nest_end(msg->skb, attrs);
+	genlmsg_end(msg->skb, hdr);
+
+	return 0;
+
+attr_msg_full:
+	nla_nest_cancel(msg->skb, attrs);
+msg_full:
+	genlmsg_cancel(msg->skb, hdr);
+
+	return -EMSGSIZE;
+}
+
+int tipc_nl_node_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	int err;
+	struct net *net = sock_net(skb->sk);
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	int done = cb->args[0];
+	int last_addr = cb->args[1];
+	struct tipc_node *node;
+	struct tipc_nl_msg msg;
+
+	if (done)
+		return 0;
+
+	msg.skb = skb;
+	msg.portid = NETLINK_CB(cb->skb).portid;
+	msg.seq = cb->nlh->nlmsg_seq;
+
+	rcu_read_lock();
+	if (last_addr) {
+		node = tipc_node_find(net, last_addr);
+		if (!node) {
+			rcu_read_unlock();
+			/* We never set seq or call nl_dump_check_consistent()
+			 * this means that setting prev_seq here will cause the
+			 * consistence check to fail in the netlink callback
+			 * handler. Resulting in the NLMSG_DONE message having
+			 * the NLM_F_DUMP_INTR flag set if the node state
+			 * changed while we released the lock.
+			 */
+			cb->prev_seq = 1;
+			return -EPIPE;
+		}
+		tipc_node_put(node);
+	}
+
+	list_for_each_entry_rcu(node, &tn->node_list, list) {
+		if (last_addr) {
+			if (node->addr == last_addr)
+				last_addr = 0;
+			else
+				continue;
+		}
+
+		tipc_node_lock(node);
+		err = __tipc_nl_add_node(&msg, node);
+		if (err) {
+			last_addr = node->addr;
+			tipc_node_unlock(node);
+			goto out;
+		}
+
+		tipc_node_unlock(node);
+	}
+	done = 1;
+out:
+	cb->args[0] = done;
+	cb->args[1] = last_addr;
+	rcu_read_unlock();
+
+	return skb->len;
+}