/*
* net/tipc/name_table.c: TIPC name table code
*
* Copyright (c) 2000-2006, 2014-2018, Ericsson AB
* Copyright (c) 2004-2008, 2010-2014, 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 <net/sock.h>
#include <linux/list_sort.h>
#include <linux/rbtree_augmented.h>
#include "core.h"
#include "netlink.h"
#include "name_table.h"
#include "name_distr.h"
#include "subscr.h"
#include "bcast.h"
#include "addr.h"
#include "node.h"
#include "group.h"
/**
* struct service_range - container for all bindings of a service range
* @lower: service range lower bound
* @upper: service range upper bound
* @tree_node: member of service range RB tree
* @max: largest 'upper' in this node subtree
* @local_publ: list of identical publications made from this node
* Used by closest_first lookup and multicast lookup algorithm
* @all_publ: all publications identical to this one, whatever node and scope
* Used by round-robin lookup algorithm
*/
struct service_range {
u32 lower;
u32 upper;
struct rb_node tree_node;
u32 max;
struct list_head local_publ;
struct list_head all_publ;
};
/**
* struct tipc_service - container for all published instances of a service type
* @type: 32 bit 'type' value for service
* @publ_cnt: increasing counter for publications in this service
* @ranges: rb tree containing all service ranges for this service
* @service_list: links to adjacent name ranges in hash chain
* @subscriptions: list of subscriptions for this service type
* @lock: spinlock controlling access to pertaining service ranges/publications
* @rcu: RCU callback head used for deferred freeing
*/
struct tipc_service {
u32 type;
u32 publ_cnt;
struct rb_root ranges;
struct hlist_node service_list;
struct list_head subscriptions;
spinlock_t lock; /* Covers service range list */
struct rcu_head rcu;
};
#define service_range_upper(sr) ((sr)->upper)
RB_DECLARE_CALLBACKS_MAX(static, sr_callbacks,
struct service_range, tree_node, u32, max,
service_range_upper)
#define service_range_entry(rbtree_node) \
(container_of(rbtree_node, struct service_range, tree_node))
#define service_range_overlap(sr, start, end) \
((sr)->lower <= (end) && (sr)->upper >= (start))
/**
* service_range_foreach_match - iterate over tipc service rbtree for each
* range match
* @sr: the service range pointer as a loop cursor
* @sc: the pointer to tipc service which holds the service range rbtree
* @start: beginning of the search range (end >= start) for matching
* @end: end of the search range (end >= start) for matching
*/
#define service_range_foreach_match(sr, sc, start, end) \
for (sr = service_range_match_first((sc)->ranges.rb_node, \
start, \
end); \
sr; \
sr = service_range_match_next(&(sr)->tree_node, \
start, \
end))
/**
* service_range_match_first - find first service range matching a range
* @n: the root node of service range rbtree for searching
* @start: beginning of the search range (end >= start) for matching
* @end: end of the search range (end >= start) for matching
*
* Return: the leftmost service range node in the rbtree that overlaps the
* specific range if any. Otherwise, returns NULL.
*/
static struct service_range *service_range_match_first(struct rb_node *n,
u32 start, u32 end)
{
struct service_range *sr;
struct rb_node *l, *r;
/* Non overlaps in tree at all? */
if (!n || service_range_entry(n)->max < start)
return NULL;
while (n) {
l = n->rb_left;
if (l && service_range_entry(l)->max >= start) {
/* A leftmost overlap range node must be one in the left
* subtree. If not, it has lower > end, then nodes on
* the right side cannot satisfy the condition either.
*/
n = l;
continue;
}
/* No one in the left subtree can match, return if this node is
* an overlap i.e. leftmost.
*/
sr = service_range_entry(n);
if (service_range_overlap(sr, start, end))
return sr;
/* Ok, try to lookup on the right side */
r = n->rb_right;
if (sr->lower <= end &&
r && service_range_entry(r)->max >= start) {
n = r;
continue;
}
break;
}
return NULL;
}
/**
* service_range_match_next - find next service range matching a range
* @n: a node in service range rbtree from which the searching starts
* @start: beginning of the search range (end >= start) for matching
* @end: end of the search range (end >= start) for matching
*
* Return: the next service range node to the given node in the rbtree that
* overlaps the specific range if any. Otherwise, returns NULL.
*/
static struct service_range *service_range_match_next(struct rb_node *n,
u32 start, u32 end)
{
struct service_range *sr;
struct rb_node *p, *r;
while (n) {
r = n->rb_right;
if (r && service_range_entry(r)->max >= start)
/* A next overlap range node must be one in the right
* subtree. If not, it has lower > end, then any next
* successor (- an ancestor) of this node cannot
* satisfy the condition either.
*/
return service_range_match_first(r, start, end);
/* No one in the right subtree can match, go up to find an
* ancestor of this node which is parent of a left-hand child.
*/
while ((p = rb_parent(n)) && n == p->rb_right)
n = p;
if (!p)
break;
/* Return if this ancestor is an overlap */
sr = service_range_entry(p);
if (service_range_overlap(sr, start, end))
return sr;
/* Ok, try to lookup more from this ancestor */
if (sr->lower <= end) {
n = p;
continue;
}
break;
}
return NULL;
}
static int hash(int x)
{
return x & (TIPC_NAMETBL_SIZE - 1);
}
/**
* tipc_publ_create - create a publication structure
* @ua: the service range the user is binding to
* @sk: the address of the socket that is bound
* @key: publication key
*/
static struct publication *tipc_publ_create(struct tipc_uaddr *ua,
struct tipc_socket_addr *sk,
u32 key)
{
struct publication *p = kzalloc(sizeof(*p), GFP_ATOMIC);
if (!p)
return NULL;
p->sr = ua->sr;
p->sk = *sk;
p->scope = ua->scope;
p->key = key;
INIT_LIST_HEAD(&p->binding_sock);
INIT_LIST_HEAD(&p->binding_node);
INIT_LIST_HEAD(&p->local_publ);
INIT_LIST_HEAD(&p->all_publ);
INIT_LIST_HEAD(&p->list);
return p;
}
/**
* tipc_service_create - create a service structure for the specified 'type'
* @net: network namespace
* @ua: address representing the service to be bound
*
* Allocates a single range structure and sets it to all 0's.
*/
static struct tipc_service *tipc_service_create(struct net *net,
struct tipc_uaddr *ua)
{
struct name_table *nt = tipc_name_table(net);
struct tipc_service *service;
struct hlist_head *hd;
service = kzalloc(sizeof(*service), GFP_ATOMIC);
if (!service) {
pr_warn("Service creation failed, no memory\n");
return NULL;
}
spin_lock_init(&service->lock);
service->type = ua->sr.type;
service->ranges = RB_ROOT;
INIT_HLIST_NODE(&service->service_list);
INIT_LIST_HEAD(&service->subscriptions);
hd = &nt->services[hash(ua->sr.type)];
hlist_add_head_rcu(&service->service_list, hd);
return service;
}
/* tipc_service_find_range - find service range matching publication parameters
*/
static struct service_range *tipc_service_find_range(struct tipc_service *sc,
struct tipc_uaddr *ua)
{
struct service_range *sr;
service_range_foreach_match(sr, sc, ua->sr.lower, ua->sr.upper) {
/* Look for exact match */
if (sr->lower == ua->sr.lower && sr->upper == ua->sr.upper)
return sr;
}
return NULL;
}
static struct service_range *tipc_service_create_range(struct tipc_service *sc,
struct publication *p)
{
struct rb_node **n, *parent = NULL;
struct service_range *sr;
u32 lower = p->sr.lower;
u32 upper = p->sr.upper;
n = &sc->ranges.rb_node;
while (*n) {
parent = *n;
sr = service_range_entry(parent);
if (lower == sr->lower && upper == sr->upper)
return sr;
if (sr->max < upper)
sr->max = upper;
if (lower <= sr->lower)
n = &parent->rb_left;
else
n = &parent->rb_right;
}
sr = kzalloc(sizeof(*sr), GFP_ATOMIC);
if (!sr)
return NULL;
sr->lower = lower;
sr->upper = upper;
sr->max = upper;
INIT_LIST_HEAD(&sr->local_publ);
INIT_LIST_HEAD(&sr->all_publ);
rb_link_node(&sr->tree_node, parent, n);
rb_insert_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks);
return sr;
}
static bool tipc_service_insert_publ(struct net *net,
struct tipc_service *sc,
struct publication *p)
{
struct tipc_subscription *sub, *tmp;
struct service_range *sr;
struct publication *_p;
u32 node = p->sk.node;
bool first = false;
bool res = false;
u32 key = p->key;
spin_lock_bh(&sc->lock);
sr = tipc_service_create_range(sc, p);
if (!sr)
goto exit;
first = list_empty(&sr->all_publ);
/* Return if the publication already exists */
list_for_each_entry(_p, &sr->all_publ, all_publ) {
if (_p->key == key && (!_p->sk.node || _p->sk.node == node)) {
pr_debug("Failed to bind duplicate %u,%u,%u/%u:%u/%u\n",
p->sr.type, p->sr.lower, p->sr.upper,
node, p->sk.ref, key);
goto exit;
}
}
if (in_own_node(net, p->sk.node))
list_add(&p->local_publ, &sr->local_publ);
list_add(&p->all_publ, &sr->all_publ);
p->id = sc->publ_cnt++;
/* Any subscriptions waiting for notification? */
list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
tipc_sub_report_overlap(sub, p, TIPC_PUBLISHED, first);
}
res = true;
exit:
if (!res)
pr_warn("Failed to bind to %u,%u,%u\n",
p->sr.type, p->sr.lower, p->sr.upper);
spin_unlock_bh(&sc->lock);
return res;
}
/**
* tipc_service_remove_publ - remove a publication from a service
* @r: service_range to remove publication from
* @sk: address publishing socket
* @key: target publication key
*/
static struct publication *tipc_service_remove_publ(struct service_range *r,
struct tipc_socket_addr *sk,
u32 key)
{
struct publication *p;
u32 node = sk->node;
list_for_each_entry(p, &r->all_publ, all_publ) {
if (p->key != key || (node && node != p->sk.node))
continue;
list_del(&p->all_publ);
list_del(&p->local_publ);
return p;
}
return NULL;
}
/*
* Code reused: time_after32() for the same purpose
*/
#define publication_after(pa, pb) time_after32((pa)->id, (pb)->id)
static int tipc_publ_sort(void *priv, const struct list_head *a,
const struct list_head *b)
{
struct publication *pa, *pb;
pa = container_of(a, struct publication, list);
pb = container_of(b, struct publication, list);
return publication_after(pa, pb);
}
/**
* tipc_service_subscribe - attach a subscription, and optionally
* issue the prescribed number of events if there is any service
* range overlapping with the requested range
* @service: the tipc_service to attach the @sub to
* @sub: the subscription to attach
*/
static void tipc_service_subscribe(struct tipc_service *service,
struct tipc_subscription *sub)
{
struct publication *p, *first, *tmp;
struct list_head publ_list;
struct service_range *sr;
u32 filter, lower, upper;
filter = sub->s.filter;
lower = sub->s.seq.lower;
upper = sub->s.seq.upper;
tipc_sub_get(sub);
list_add(&sub->service_list, &service->subscriptions);
if (filter & TIPC_SUB_NO_STATUS)
return;
INIT_LIST_HEAD(&publ_list);
service_range_foreach_match(sr, service, lower, upper) {
first = NULL;
list_for_each_entry(p, &sr->all_publ, all_publ) {
if (filter & TIPC_SUB_PORTS)
list_add_tail(&p->list, &publ_list);
else if (!first || publication_after(first, p))
/* Pick this range's *first* publication */
first = p;
}
if (first)
list_add_tail(&first->list, &publ_list);
}
/* Sort the publications before reporting */
list_sort(NULL, &publ_list, tipc_publ_sort);
list_for_each_entry_safe(p, tmp, &publ_list, list) {
tipc_sub_report_overlap(sub, p, TIPC_PUBLISHED, true);
list_del_init(&p->list);
}
}
static struct tipc_service *tipc_service_find(struct net *net,
struct tipc_uaddr *ua)
{
struct name_table *nt = tipc_name_table(net);
struct hlist_head *service_head;
struct tipc_service *service;
service_head = &nt->services[hash(ua->sr.type)];
hlist_for_each_entry_rcu(service, service_head, service_list) {
if (service->type == ua->sr.type)
return service;
}
return NULL;
};
struct publication *tipc_nametbl_insert_publ(struct net *net,
struct tipc_uaddr *ua,
struct tipc_socket_addr *sk,
u32 key)
{
struct tipc_service *sc;
struct publication *p;
p = tipc_publ_create(ua, sk, key);
if (!p)
return NULL;
sc = tipc_service_find(net, ua);
if (!sc)
sc = tipc_service_create(net, ua);
if (sc && tipc_service_insert_publ(net, sc, p))
return p;
kfree(p);
return NULL;
}
struct publication *tipc_nametbl_remove_publ(struct net *net,
struct tipc_uaddr *ua,
struct tipc_socket_addr *sk,
u32 key)
{
struct tipc_subscription *sub, *tmp;
struct publication *p = NULL;
struct service_range *sr;
struct tipc_service *sc;
bool last;
sc = tipc_service_find(net, ua);
if (!sc)
goto exit;
spin_lock_bh(&sc->lock);
sr = tipc_service_find_range(sc, ua);
if (!sr)
goto unlock;
p = tipc_service_remove_publ(sr, sk, key);
if (!p)
goto unlock;
/* Notify any waiting subscriptions */
last = list_empty(&sr->all_publ);
list_for_each_entry_safe(sub, tmp, &sc->subscriptions, service_list) {
tipc_sub_report_overlap(sub, p, TIPC_WITHDRAWN, last);
}
/* Remove service range item if this was its last publication */
if (list_empty(&sr->all_publ)) {
rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks);
kfree(sr);
}
/* Delete service item if no more publications and subscriptions */
if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
hlist_del_init_rcu(&sc->service_list);
kfree_rcu(sc, rcu);
}
unlock:
spin_unlock_bh(&sc->lock);
exit:
if (!p) {
pr_err("Failed to remove unknown binding: %u,%u,%u/%u:%u/%u\n",
ua->sr.type, ua->sr.lower, ua->sr.upper,
sk->node, sk->ref, key);
}
return p;
}
/**
* tipc_nametbl_lookup_anycast - perform service instance to socket translation
* @net: network namespace
* @ua: service address to look up
* @sk: address to socket we want to find
*
* On entry, a non-zero 'sk->node' indicates the node where we want lookup to be
* performed, which may not be this one.
*
* On exit:
*
* - If lookup is deferred to another node, leave 'sk->node' unchanged and
* return 'true'.
* - If lookup is successful, set the 'sk->node' and 'sk->ref' (== portid) which
* represent the bound socket and return 'true'.
* - If lookup fails, return 'false'
*
* Note that for legacy users (node configured with Z.C.N address format) the
* 'closest-first' lookup algorithm must be maintained, i.e., if sk.node is 0
* we must look in the local binding list first
*/
bool tipc_nametbl_lookup_anycast(struct net *net,
struct tipc_uaddr *ua,
struct tipc_socket_addr *sk)
{
struct tipc_net *tn = tipc_net(net);
bool legacy = tn->legacy_addr_format;
u32 self = tipc_own_addr(net);
u32 inst = ua->sa.instance;
struct service_range *r;
struct tipc_service *sc;
struct publication *p;
struct list_head *l;
bool res = false;
if (!tipc_in_scope(legacy, sk->node, self))
return true;
rcu_read_lock();
sc = tipc_service_find(net, ua);
if (unlikely(!sc))
goto exit;
spin_lock_bh(&sc->lock);
service_range_foreach_match(r, sc, inst, inst) {
/* Select lookup algo: local, closest-first or round-robin */
if (sk->node == self) {
l = &r->local_publ;
if (list_empty(l))
continue;
p = list_first_entry(l, struct publication, local_publ);
list_move_tail(&p->local_publ, &r->local_publ);
} else if (legacy && !sk->node && !list_empty(&r->local_publ)) {
l = &r->local_publ;
p = list_first_entry(l, struct publication, local_publ);
list_move_tail(&p->local_publ, &r->local_publ);
} else {
l = &r->all_publ;
p = list_first_entry(l, struct publication, all_publ);
list_move_tail(&p->all_publ, &r->all_publ);
}
*sk = p->sk;
res = true;
/* Todo: as for legacy, pick the first matching range only, a
* "true" round-robin will be performed as needed.
*/
break;
}
spin_unlock_bh(&sc->lock);
exit:
rcu_read_unlock();
return res;
}
/* tipc_nametbl_lookup_group(): lookup destinaton(s) in a communication group
* Returns a list of one (== group anycast) or more (== group multicast)
* destination socket/node pairs matching the given address.
* The requester may or may not want to exclude himself from the list.
*/
bool tipc_nametbl_lookup_group(struct net *net, struct tipc_uaddr *ua,
struct list_head *dsts, int *dstcnt,
u32 exclude, bool mcast)
{
u32 self = tipc_own_addr(net);
u32 inst = ua->sa.instance;
struct service_range *sr;
struct tipc_service *sc;
struct publication *p;
*dstcnt = 0;
rcu_read_lock();
sc = tipc_service_find(net, ua);
if (unlikely(!sc))
goto exit;
spin_lock_bh(&sc->lock);
/* Todo: a full search i.e. service_range_foreach_match() instead? */
sr = service_range_match_first(sc->ranges.rb_node, inst, inst);
if (!sr)
goto no_match;
list_for_each_entry(p, &sr->all_publ, all_publ) {
if (p->scope != ua->scope)
continue;
if (p->sk.ref == exclude && p->sk.node == self)
continue;
tipc_dest_push(dsts, p->sk.node, p->sk.ref);
(*dstcnt)++;
if (mcast)
continue;
list_move_tail(&p->all_publ, &sr->all_publ);
break;
}
no_match:
spin_unlock_bh(&sc->lock);
exit:
rcu_read_unlock();
return !list_empty(dsts);
}
/* tipc_nametbl_lookup_mcast_sockets(): look up node local destinaton sockets
* matching the given address
* Used on nodes which have received a multicast/broadcast message
* Returns a list of local sockets
*/
void tipc_nametbl_lookup_mcast_sockets(struct net *net, struct tipc_uaddr *ua,
struct list_head *dports)
{
struct service_range *sr;
struct tipc_service *sc;
struct publication *p;
u8 scope = ua->scope;
rcu_read_lock();
sc = tipc_service_find(net, ua);
if (!sc)
goto exit;
spin_lock_bh(&sc->lock);
service_range_foreach_match(sr, sc, ua->sr.lower, ua->sr.upper) {
list_for_each_entry(p, &sr->local_publ, local_publ) {
if (scope == p->scope || scope == TIPC_ANY_SCOPE)
tipc_dest_push(dports, 0, p->sk.ref);
}
}
spin_unlock_bh(&sc->lock);
exit:
rcu_read_unlock();
}
/* tipc_nametbl_lookup_mcast_nodes(): look up all destination nodes matching
* the given address. Used in sending node.
* Used on nodes which are sending out a multicast/broadcast message
* Returns a list of nodes, including own node if applicable
*/
void tipc_nametbl_lookup_mcast_nodes(struct net *net, struct tipc_uaddr *ua,
struct tipc_nlist *nodes)
{
struct service_range *sr;
struct tipc_service *sc;
struct publication *p;
rcu_read_lock();
sc = tipc_service_find(net, ua);
if (!sc)
goto exit;
spin_lock_bh(&sc->lock);
service_range_foreach_match(sr, sc, ua->sr.lower, ua->sr.upper) {
list_for_each_entry(p, &sr->all_publ, all_publ) {
tipc_nlist_add(nodes, p->sk.node);
}
}
spin_unlock_bh(&sc->lock);
exit:
rcu_read_unlock();
}
/* tipc_nametbl_build_group - build list of communication group members
*/
void tipc_nametbl_build_group(struct net *net, struct tipc_group *grp,
struct tipc_uaddr *ua)
{
struct service_range *sr;
struct tipc_service *sc;
struct publication *p;
struct rb_node *n;
rcu_read_lock();
sc = tipc_service_find(net, ua);
if (!sc)
goto exit;
spin_lock_bh(&sc->lock);
for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
sr = container_of(n, struct service_range, tree_node);
list_for_each_entry(p, &sr->all_publ, all_publ) {
if (p->scope != ua->scope)
continue;
tipc_group_add_member(grp, p->sk.node, p->sk.ref,
p->sr.lower);
}
}
spin_unlock_bh(&sc->lock);
exit:
rcu_read_unlock();
}
/* tipc_nametbl_publish - add service binding to name table
*/
struct publication *tipc_nametbl_publish(struct net *net, struct tipc_uaddr *ua,
struct tipc_socket_addr *sk, u32 key)
{
struct name_table *nt = tipc_name_table(net);
struct tipc_net *tn = tipc_net(net);
struct publication *p = NULL;
struct sk_buff *skb = NULL;
u32 rc_dests;
spin_lock_bh(&tn->nametbl_lock);
if (nt->local_publ_count >= TIPC_MAX_PUBL) {
pr_warn("Bind failed, max limit %u reached\n", TIPC_MAX_PUBL);
goto exit;
}
p = tipc_nametbl_insert_publ(net, ua, sk, key);
if (p) {
nt->local_publ_count++;
skb = tipc_named_publish(net, p);
}
rc_dests = nt->rc_dests;
exit:
spin_unlock_bh(&tn->nametbl_lock);
if (skb)
tipc_node_broadcast(net, skb, rc_dests);
return p;
}
/**
* tipc_nametbl_withdraw - withdraw a service binding
* @net: network namespace
* @ua: service address/range being unbound
* @sk: address of the socket being unbound from
* @key: target publication key
*/
void tipc_nametbl_withdraw(struct net *net, struct tipc_uaddr *ua,
struct tipc_socket_addr *sk, u32 key)
{
struct name_table *nt = tipc_name_table(net);
struct tipc_net *tn = tipc_net(net);
struct sk_buff *skb = NULL;
struct publication *p;
u32 rc_dests;
spin_lock_bh(&tn->nametbl_lock);
p = tipc_nametbl_remove_publ(net, ua, sk, key);
if (p) {
nt->local_publ_count--;
skb = tipc_named_withdraw(net, p);
list_del_init(&p->binding_sock);
kfree_rcu(p, rcu);
}
rc_dests = nt->rc_dests;
spin_unlock_bh(&tn->nametbl_lock);
if (skb)
tipc_node_broadcast(net, skb, rc_dests);
}
/**
* tipc_nametbl_subscribe - add a subscription object to the name table
* @sub: subscription to add
*/
bool tipc_nametbl_subscribe(struct tipc_subscription *sub)
{
struct tipc_net *tn = tipc_net(sub->net);
u32 type = sub->s.seq.type;
struct tipc_service *sc;
struct tipc_uaddr ua;
bool res = true;
tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_NODE_SCOPE, type,
sub->s.seq.lower, sub->s.seq.upper);
spin_lock_bh(&tn->nametbl_lock);
sc = tipc_service_find(sub->net, &ua);
if (!sc)
sc = tipc_service_create(sub->net, &ua);
if (sc) {
spin_lock_bh(&sc->lock);
tipc_service_subscribe(sc, sub);
spin_unlock_bh(&sc->lock);
} else {
pr_warn("Failed to subscribe for {%u,%u,%u}\n",
type, sub->s.seq.lower, sub->s.seq.upper);
res = false;
}
spin_unlock_bh(&tn->nametbl_lock);
return res;
}
/**
* tipc_nametbl_unsubscribe - remove a subscription object from name table
* @sub: subscription to remove
*/
void tipc_nametbl_unsubscribe(struct tipc_subscription *sub)
{
struct tipc_net *tn = tipc_net(sub->net);
struct tipc_service *sc;
struct tipc_uaddr ua;
tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_NODE_SCOPE,
sub->s.seq.type, sub->s.seq.lower, sub->s.seq.upper);
spin_lock_bh(&tn->nametbl_lock);
sc = tipc_service_find(sub->net, &ua);
if (!sc)
goto exit;
spin_lock_bh(&sc->lock);
list_del_init(&sub->service_list);
tipc_sub_put(sub);
/* Delete service item if no more publications and subscriptions */
if (RB_EMPTY_ROOT(&sc->ranges) && list_empty(&sc->subscriptions)) {
hlist_del_init_rcu(&sc->service_list);
kfree_rcu(sc, rcu);
}
spin_unlock_bh(&sc->lock);
exit:
spin_unlock_bh(&tn->nametbl_lock);
}
int tipc_nametbl_init(struct net *net)
{
struct tipc_net *tn = tipc_net(net);
struct name_table *nt;
int i;
nt = kzalloc(sizeof(*nt), GFP_KERNEL);
if (!nt)
return -ENOMEM;
for (i = 0; i < TIPC_NAMETBL_SIZE; i++)
INIT_HLIST_HEAD(&nt->services[i]);
INIT_LIST_HEAD(&nt->node_scope);
INIT_LIST_HEAD(&nt->cluster_scope);
rwlock_init(&nt->cluster_scope_lock);
tn->nametbl = nt;
spin_lock_init(&tn->nametbl_lock);
return 0;
}
/**
* tipc_service_delete - purge all publications for a service and delete it
* @net: the associated network namespace
* @sc: tipc_service to delete
*/
static void tipc_service_delete(struct net *net, struct tipc_service *sc)
{
struct service_range *sr, *tmpr;
struct publication *p, *tmp;
spin_lock_bh(&sc->lock);
rbtree_postorder_for_each_entry_safe(sr, tmpr, &sc->ranges, tree_node) {
list_for_each_entry_safe(p, tmp, &sr->all_publ, all_publ) {
tipc_service_remove_publ(sr, &p->sk, p->key);
kfree_rcu(p, rcu);
}
rb_erase_augmented(&sr->tree_node, &sc->ranges, &sr_callbacks);
kfree(sr);
}
hlist_del_init_rcu(&sc->service_list);
spin_unlock_bh(&sc->lock);
kfree_rcu(sc, rcu);
}
void tipc_nametbl_stop(struct net *net)
{
struct name_table *nt = tipc_name_table(net);
struct tipc_net *tn = tipc_net(net);
struct hlist_head *service_head;
struct tipc_service *service;
u32 i;
/* Verify name table is empty and purge any lingering
* publications, then release the name table
*/
spin_lock_bh(&tn->nametbl_lock);
for (i = 0; i < TIPC_NAMETBL_SIZE; i++) {
if (hlist_empty(&nt->services[i]))
continue;
service_head = &nt->services[i];
hlist_for_each_entry_rcu(service, service_head, service_list) {
tipc_service_delete(net, service);
}
}
spin_unlock_bh(&tn->nametbl_lock);
synchronize_net();
kfree(nt);
}
static int __tipc_nl_add_nametable_publ(struct tipc_nl_msg *msg,
struct tipc_service *service,
struct service_range *sr,
u32 *last_key)
{
struct publication *p;
struct nlattr *attrs;
struct nlattr *b;
void *hdr;
if (*last_key) {
list_for_each_entry(p, &sr->all_publ, all_publ)
if (p->key == *last_key)
break;
if (list_entry_is_head(p, &sr->all_publ, all_publ))
return -EPIPE;
} else {
p = list_first_entry(&sr->all_publ,
struct publication,
all_publ);
}
list_for_each_entry_from(p, &sr->all_publ, all_publ) {
*last_key = p->key;
hdr = genlmsg_put(msg->skb, msg->portid, msg->seq,
&tipc_genl_family, NLM_F_MULTI,
TIPC_NL_NAME_TABLE_GET);
if (!hdr)
return -EMSGSIZE;
attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE);
if (!attrs)
goto msg_full;
b = nla_nest_start_noflag(msg->skb, TIPC_NLA_NAME_TABLE_PUBL);
if (!b)
goto attr_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_TYPE, service->type))
goto publ_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_LOWER, sr->lower))
goto publ_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_UPPER, sr->upper))
goto publ_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_SCOPE, p->scope))
goto publ_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_NODE, p->sk.node))
goto publ_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_REF, p->sk.ref))
goto publ_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_PUBL_KEY, p->key))
goto publ_msg_full;
nla_nest_end(msg->skb, b);
nla_nest_end(msg->skb, attrs);
genlmsg_end(msg->skb, hdr);
}
*last_key = 0;
return 0;
publ_msg_full:
nla_nest_cancel(msg->skb, b);
attr_msg_full:
nla_nest_cancel(msg->skb, attrs);
msg_full:
genlmsg_cancel(msg->skb, hdr);
return -EMSGSIZE;
}
static int __tipc_nl_service_range_list(struct tipc_nl_msg *msg,
struct tipc_service *sc,
u32 *last_lower, u32 *last_key)
{
struct service_range *sr;
struct rb_node *n;
int err;
for (n = rb_first(&sc->ranges); n; n = rb_next(n)) {
sr = container_of(n, struct service_range, tree_node);
if (sr->lower < *last_lower)
continue;
err = __tipc_nl_add_nametable_publ(msg, sc, sr, last_key);
if (err) {
*last_lower = sr->lower;
return err;
}
}
*last_lower = 0;
return 0;
}
static int tipc_nl_service_list(struct net *net, struct tipc_nl_msg *msg,
u32 *last_type, u32 *last_lower, u32 *last_key)
{
struct tipc_net *tn = tipc_net(net);
struct tipc_service *service = NULL;
struct hlist_head *head;
struct tipc_uaddr ua;
int err;
int i;
if (*last_type)
i = hash(*last_type);
else
i = 0;
for (; i < TIPC_NAMETBL_SIZE; i++) {
head = &tn->nametbl->services[i];
if (*last_type ||
(!i && *last_key && (*last_lower == *last_key))) {
tipc_uaddr(&ua, TIPC_SERVICE_RANGE, TIPC_NODE_SCOPE,
*last_type, *last_lower, *last_lower);
service = tipc_service_find(net, &ua);
if (!service)
return -EPIPE;
} else {
hlist_for_each_entry_rcu(service, head, service_list)
break;
if (!service)
continue;
}
hlist_for_each_entry_from_rcu(service, service_list) {
spin_lock_bh(&service->lock);
err = __tipc_nl_service_range_list(msg, service,
last_lower,
last_key);
if (err) {
*last_type = service->type;
spin_unlock_bh(&service->lock);
return err;
}
spin_unlock_bh(&service->lock);
}
*last_type = 0;
}
return 0;
}
int tipc_nl_name_table_dump(struct sk_buff *skb, struct netlink_callback *cb)
{
struct net *net = sock_net(skb->sk);
u32 last_type = cb->args[0];
u32 last_lower = cb->args[1];
u32 last_key = cb->args[2];
int done = cb->args[3];
struct tipc_nl_msg msg;
int err;
if (done)
return 0;
msg.skb = skb;
msg.portid = NETLINK_CB(cb->skb).portid;
msg.seq = cb->nlh->nlmsg_seq;
rcu_read_lock();
err = tipc_nl_service_list(net, &msg, &last_type,
&last_lower, &last_key);
if (!err) {
done = 1;
} else if (err != -EMSGSIZE) {
/* 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
* we got an error.
*/
cb->prev_seq = 1;
}
rcu_read_unlock();
cb->args[0] = last_type;
cb->args[1] = last_lower;
cb->args[2] = last_key;
cb->args[3] = done;
return skb->len;
}
struct tipc_dest *tipc_dest_find(struct list_head *l, u32 node, u32 port)
{
struct tipc_dest *dst;
list_for_each_entry(dst, l, list) {
if (dst->node == node && dst->port == port)
return dst;
}
return NULL;
}
bool tipc_dest_push(struct list_head *l, u32 node, u32 port)
{
struct tipc_dest *dst;
if (tipc_dest_find(l, node, port))
return false;
dst = kmalloc(sizeof(*dst), GFP_ATOMIC);
if (unlikely(!dst))
return false;
dst->node = node;
dst->port = port;
list_add(&dst->list, l);
return true;
}
bool tipc_dest_pop(struct list_head *l, u32 *node, u32 *port)
{
struct tipc_dest *dst;
if (list_empty(l))
return false;
dst = list_first_entry(l, typeof(*dst), list);
if (port)
*port = dst->port;
if (node)
*node = dst->node;
list_del(&dst->list);
kfree(dst);
return true;
}
bool tipc_dest_del(struct list_head *l, u32 node, u32 port)
{
struct tipc_dest *dst;
dst = tipc_dest_find(l, node, port);
if (!dst)
return false;
list_del(&dst->list);
kfree(dst);
return true;
}
void tipc_dest_list_purge(struct list_head *l)
{
struct tipc_dest *dst, *tmp;
list_for_each_entry_safe(dst, tmp, l, list) {
list_del(&dst->list);
kfree(dst);
}
}
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