/*
* net/tipc/name_distr.c: TIPC name distribution code
*
* Copyright (c) 2000-2006, 2014-2019, Ericsson AB
* Copyright (c) 2005, 2010-2011, Wind River Systems
* Copyright (c) 2020-2021, Red Hat Inc
* 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 "name_distr.h"
int sysctl_tipc_named_timeout __read_mostly = 2000;
/**
* publ_to_item - add publication info to a publication message
* @p: publication info
* @i: location of item in the message
*/
static void publ_to_item(struct distr_item *i, struct publication *p)
{
i->type = htonl(p->sr.type);
i->lower = htonl(p->sr.lower);
i->upper = htonl(p->sr.upper);
i->port = htonl(p->sk.ref);
i->key = htonl(p->key);
}
/**
* named_prepare_buf - allocate & initialize a publication message
* @net: the associated network namespace
* @type: message type
* @size: payload size
* @dest: destination node
*
* The buffer returned is of size INT_H_SIZE + payload size
*/
static struct sk_buff *named_prepare_buf(struct net *net, u32 type, u32 size,
u32 dest)
{
struct sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size, GFP_ATOMIC);
u32 self = tipc_own_addr(net);
struct tipc_msg *msg;
if (buf != NULL) {
msg = buf_msg(buf);
tipc_msg_init(self, msg, NAME_DISTRIBUTOR,
type, INT_H_SIZE, dest);
msg_set_size(msg, INT_H_SIZE + size);
}
return buf;
}
/**
* tipc_named_publish - tell other nodes about a new publication by this node
* @net: the associated network namespace
* @p: the new publication
*/
struct sk_buff *tipc_named_publish(struct net *net, struct publication *p)
{
struct name_table *nt = tipc_name_table(net);
struct distr_item *item;
struct sk_buff *skb;
if (p->scope == TIPC_NODE_SCOPE) {
list_add_tail_rcu(&p->binding_node, &nt->node_scope);
return NULL;
}
write_lock_bh(&nt->cluster_scope_lock);
list_add_tail(&p->binding_node, &nt->cluster_scope);
write_unlock_bh(&nt->cluster_scope_lock);
skb = named_prepare_buf(net, PUBLICATION, ITEM_SIZE, 0);
if (!skb) {
pr_warn("Publication distribution failure\n");
return NULL;
}
msg_set_named_seqno(buf_msg(skb), nt->snd_nxt++);
msg_set_non_legacy(buf_msg(skb));
item = (struct distr_item *)msg_data(buf_msg(skb));
publ_to_item(item, p);
return skb;
}
/**
* tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
* @net: the associated network namespace
* @p: the withdrawn publication
*/
struct sk_buff *tipc_named_withdraw(struct net *net, struct publication *p)
{
struct name_table *nt = tipc_name_table(net);
struct distr_item *item;
struct sk_buff *skb;
write_lock_bh(&nt->cluster_scope_lock);
list_del(&p->binding_node);
write_unlock_bh(&nt->cluster_scope_lock);
if (p->scope == TIPC_NODE_SCOPE)
return NULL;
skb = named_prepare_buf(net, WITHDRAWAL, ITEM_SIZE, 0);
if (!skb) {
pr_warn("Withdrawal distribution failure\n");
return NULL;
}
msg_set_named_seqno(buf_msg(skb), nt->snd_nxt++);
msg_set_non_legacy(buf_msg(skb));
item = (struct distr_item *)msg_data(buf_msg(skb));
publ_to_item(item, p);
return skb;
}
/**
* named_distribute - prepare name info for bulk distribution to another node
* @net: the associated network namespace
* @list: list of messages (buffers) to be returned from this function
* @dnode: node to be updated
* @pls: linked list of publication items to be packed into buffer chain
* @seqno: sequence number for this message
*/
static void named_distribute(struct net *net, struct sk_buff_head *list,
u32 dnode, struct list_head *pls, u16 seqno)
{
struct publication *publ;
struct sk_buff *skb = NULL;
struct distr_item *item = NULL;
u32 msg_dsz = ((tipc_node_get_mtu(net, dnode, 0, false) - INT_H_SIZE) /
ITEM_SIZE) * ITEM_SIZE;
u32 msg_rem = msg_dsz;
struct tipc_msg *hdr;
list_for_each_entry(publ, pls, binding_node) {
/* Prepare next buffer: */
if (!skb) {
skb = named_prepare_buf(net, PUBLICATION, msg_rem,
dnode);
if (!skb) {
pr_warn("Bulk publication failure\n");
return;
}
hdr = buf_msg(skb);
msg_set_bc_ack_invalid(hdr, true);
msg_set_bulk(hdr);
msg_set_non_legacy(hdr);
item = (struct distr_item *)msg_data(hdr);
}
/* Pack publication into message: */
publ_to_item(item, publ);
item++;
msg_rem -= ITEM_SIZE;
/* Append full buffer to list: */
if (!msg_rem) {
__skb_queue_tail(list, skb);
skb = NULL;
msg_rem = msg_dsz;
}
}
if (skb) {
hdr = buf_msg(skb);
msg_set_size(hdr, INT_H_SIZE + (msg_dsz - msg_rem));
skb_trim(skb, INT_H_SIZE + (msg_dsz - msg_rem));
__skb_queue_tail(list, skb);
}
hdr = buf_msg(skb_peek_tail(list));
msg_set_last_bulk(hdr);
msg_set_named_seqno(hdr, seqno);
}
/**
* tipc_named_node_up - tell specified node about all publications by this node
* @net: the associated network namespace
* @dnode: destination node
* @capabilities: peer node's capabilities
*/
void tipc_named_node_up(struct net *net, u32 dnode, u16 capabilities)
{
struct name_table *nt = tipc_name_table(net);
struct tipc_net *tn = tipc_net(net);
struct sk_buff_head head;
u16 seqno;
__skb_queue_head_init(&head);
spin_lock_bh(&tn->nametbl_lock);
if (!(capabilities & TIPC_NAMED_BCAST))
nt->rc_dests++;
seqno = nt->snd_nxt;
spin_unlock_bh(&tn->nametbl_lock);
read_lock_bh(&nt->cluster_scope_lock);
named_distribute(net, &head, dnode, &nt->cluster_scope, seqno);
tipc_node_xmit(net, &head, dnode, 0);
read_unlock_bh(&nt->cluster_scope_lock);
}
/**
* tipc_publ_purge - remove publication associated with a failed node
* @net: the associated network namespace
* @p: the publication to remove
* @addr: failed node's address
*
* Invoked for each publication issued by a newly failed node.
* Removes publication structure from name table & deletes it.
*/
static void tipc_publ_purge(struct net *net, struct publication *p, u32 addr)
{
struct tipc_net *tn = tipc_net(net);
struct publication *_p;
struct tipc_uaddr ua;
tipc_uaddr(&ua, TIPC_SERVICE_RANGE, p->scope, p->sr.type,
p->sr.lower, p->sr.upper);
spin_lock_bh(&tn->nametbl_lock);
_p = tipc_nametbl_remove_publ(net, &ua, &p->sk, p->key);
if (_p)
tipc_node_unsubscribe(net, &_p->binding_node, addr);
spin_unlock_bh(&tn->nametbl_lock);
if (_p)
kfree_rcu(_p, rcu);
}
void tipc_publ_notify(struct net *net, struct list_head *nsub_list,
u32 addr, u16 capabilities)
{
struct name_table *nt = tipc_name_table(net);
struct tipc_net *tn = tipc_net(net);
struct publication *publ, *tmp;
list_for_each_entry_safe(publ, tmp, nsub_list, binding_node)
tipc_publ_purge(net, publ, addr);
spin_lock_bh(&tn->nametbl_lock);
if (!(capabilities & TIPC_NAMED_BCAST))
nt->rc_dests--;
spin_unlock_bh(&tn->nametbl_lock);
}
/**
* tipc_update_nametbl - try to process a nametable update and notify
* subscribers
* @net: the associated network namespace
* @i: location of item in the message
* @node: node address
* @dtype: name distributor message type
*
* tipc_nametbl_lock must be held.
* Return: the publication item if successful, otherwise NULL.
*/
static bool tipc_update_nametbl(struct net *net, struct distr_item *i,
u32 node, u32 dtype)
{
struct publication *p = NULL;
struct tipc_socket_addr sk;
struct tipc_uaddr ua;
u32 key = ntohl(i->key);
tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_CLUSTER_SCOPE,
ntohl(i->type), ntohl(i->lower), ntohl(i->upper));
sk.ref = ntohl(i->port);
sk.node = node;
if (dtype == PUBLICATION) {
p = tipc_nametbl_insert_publ(net, &ua, &sk, key);
if (p) {
tipc_node_subscribe(net, &p->binding_node, node);
return true;
}
} else if (dtype == WITHDRAWAL) {
p = tipc_nametbl_remove_publ(net, &ua, &sk, key);
if (p) {
tipc_node_unsubscribe(net, &p->binding_node, node);
kfree_rcu(p, rcu);
return true;
}
pr_warn_ratelimited("Failed to remove binding %u,%u from %u\n",
ua.sr.type, ua.sr.lower, node);
} else {
pr_warn_ratelimited("Unknown name table message received\n");
}
return false;
}
static struct sk_buff *tipc_named_dequeue(struct sk_buff_head *namedq,
u16 *rcv_nxt, bool *open)
{
struct sk_buff *skb, *tmp;
struct tipc_msg *hdr;
u16 seqno;
spin_lock_bh(&namedq->lock);
skb_queue_walk_safe(namedq, skb, tmp) {
if (unlikely(skb_linearize(skb))) {
__skb_unlink(skb, namedq);
kfree_skb(skb);
continue;
}
hdr = buf_msg(skb);
seqno = msg_named_seqno(hdr);
if (msg_is_last_bulk(hdr)) {
*rcv_nxt = seqno;
*open = true;
}
if (msg_is_bulk(hdr) || msg_is_legacy(hdr)) {
__skb_unlink(skb, namedq);
spin_unlock_bh(&namedq->lock);
return skb;
}
if (*open && (*rcv_nxt == seqno)) {
(*rcv_nxt)++;
__skb_unlink(skb, namedq);
spin_unlock_bh(&namedq->lock);
return skb;
}
if (less(seqno, *rcv_nxt)) {
__skb_unlink(skb, namedq);
kfree_skb(skb);
continue;
}
}
spin_unlock_bh(&namedq->lock);
return NULL;
}
/**
* tipc_named_rcv - process name table update messages sent by another node
* @net: the associated network namespace
* @namedq: queue to receive from
* @rcv_nxt: store last received seqno here
* @open: last bulk msg was received (FIXME)
*/
void tipc_named_rcv(struct net *net, struct sk_buff_head *namedq,
u16 *rcv_nxt, bool *open)
{
struct tipc_net *tn = tipc_net(net);
struct distr_item *item;
struct tipc_msg *hdr;
struct sk_buff *skb;
u32 count, node;
spin_lock_bh(&tn->nametbl_lock);
while ((skb = tipc_named_dequeue(namedq, rcv_nxt, open))) {
hdr = buf_msg(skb);
node = msg_orignode(hdr);
item = (struct distr_item *)msg_data(hdr);
count = msg_data_sz(hdr) / ITEM_SIZE;
while (count--) {
tipc_update_nametbl(net, item, node, msg_type(hdr));
item++;
}
kfree_skb(skb);
}
spin_unlock_bh(&tn->nametbl_lock);
}
/**
* tipc_named_reinit - re-initialize local publications
* @net: the associated network namespace
*
* This routine is called whenever TIPC networking is enabled.
* All name table entries published by this node are updated to reflect
* the node's new network address.
*/
void tipc_named_reinit(struct net *net)
{
struct name_table *nt = tipc_name_table(net);
struct tipc_net *tn = tipc_net(net);
struct publication *p;
u32 self = tipc_own_addr(net);
spin_lock_bh(&tn->nametbl_lock);
list_for_each_entry_rcu(p, &nt->node_scope, binding_node)
p->sk.node = self;
list_for_each_entry_rcu(p, &nt->cluster_scope, binding_node)
p->sk.node = self;
nt->rc_dests = 0;
spin_unlock_bh(&tn->nametbl_lock);
}
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