| /* |
| * net/tipc/node.c: TIPC node management routines |
| * |
| * Copyright (c) 2000-2006, 2012-2015, 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" |
| #include "bcast.h" |
| #include "discover.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); |
| static void tipc_node_timeout(unsigned long data); |
| static void tipc_node_fsm_evt(struct tipc_node *n, int evt); |
| |
| 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.namedq); |
| __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->state = SELF_DOWN_PEER_LEAVING; |
| n_ptr->signature = INVALID_NODE_SIG; |
| n_ptr->active_links[0] = INVALID_BEARER_ID; |
| n_ptr->active_links[1] = INVALID_BEARER_ID; |
| tipc_node_get(n_ptr); |
| setup_timer(&n_ptr->timer, tipc_node_timeout, (unsigned long)n_ptr); |
| n_ptr->keepalive_intv = U32_MAX; |
| exit: |
| spin_unlock_bh(&tn->node_list_lock); |
| return n_ptr; |
| } |
| |
| static void tipc_node_calculate_timer(struct tipc_node *n, struct tipc_link *l) |
| { |
| unsigned long tol = l->tolerance; |
| unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4; |
| unsigned long keepalive_intv = msecs_to_jiffies(intv); |
| |
| /* Link with lowest tolerance determines timer interval */ |
| if (keepalive_intv < n->keepalive_intv) |
| n->keepalive_intv = keepalive_intv; |
| |
| /* Ensure link's abort limit corresponds to current interval */ |
| l->abort_limit = l->tolerance / jiffies_to_msecs(n->keepalive_intv); |
| } |
| |
| 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) { |
| if (del_timer(&node->timer)) |
| tipc_node_put(node); |
| 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_timeout - handle expiration of node timer |
| */ |
| static void tipc_node_timeout(unsigned long data) |
| { |
| struct tipc_node *n = (struct tipc_node *)data; |
| struct sk_buff_head xmitq; |
| struct tipc_link *l; |
| struct tipc_media_addr *maddr; |
| int bearer_id; |
| int rc = 0; |
| |
| __skb_queue_head_init(&xmitq); |
| |
| for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) { |
| tipc_node_lock(n); |
| l = n->links[bearer_id].link; |
| if (l) { |
| /* Link tolerance may change asynchronously: */ |
| tipc_node_calculate_timer(n, l); |
| rc = tipc_link_timeout(l, &xmitq); |
| if (rc & TIPC_LINK_DOWN_EVT) |
| tipc_link_reset(l); |
| } |
| tipc_node_unlock(n); |
| maddr = &n->links[bearer_id].maddr; |
| tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr); |
| } |
| if (!mod_timer(&n->timer, jiffies + n->keepalive_intv)) |
| tipc_node_get(n); |
| tipc_node_put(n); |
| } |
| |
| /** |
| * 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, int bearer_id) |
| { |
| int *slot0 = &n->active_links[0]; |
| int *slot1 = &n->active_links[1]; |
| struct tipc_link_entry *links = n->links; |
| struct tipc_link *l = n->links[bearer_id].link; |
| |
| /* Leave room for tunnel header when returning 'mtu' to users: */ |
| links[bearer_id].mtu = l->mtu - INT_H_SIZE; |
| |
| n->working_links++; |
| n->action_flags |= TIPC_NOTIFY_LINK_UP; |
| n->link_id = l->peer_bearer_id << 16 | l->bearer_id; |
| |
| tipc_bearer_add_dest(n->net, bearer_id, n->addr); |
| |
| pr_debug("Established link <%s> on network plane %c\n", |
| l->name, l->net_plane); |
| |
| /* No active links ? => take both active slots */ |
| if (!tipc_node_is_up(n)) { |
| *slot0 = bearer_id; |
| *slot1 = bearer_id; |
| node_established_contact(n); |
| return; |
| } |
| |
| /* Lower prio than current active ? => no slot */ |
| if (l->priority < links[*slot0].link->priority) { |
| pr_debug("New link <%s> becomes standby\n", l->name); |
| return; |
| } |
| tipc_link_dup_queue_xmit(links[*slot0].link, l); |
| |
| /* Same prio as current active ? => take one slot */ |
| if (l->priority == links[*slot0].link->priority) { |
| *slot0 = bearer_id; |
| return; |
| } |
| |
| /* Higher prio than current active => take both active slots */ |
| pr_debug("Old link <%s> now standby\n", links[*slot0].link->name); |
| *slot0 = bearer_id; |
| *slot1 = bearer_id; |
| } |
| |
| /** |
| * tipc_node_link_down - handle loss of link |
| */ |
| void tipc_node_link_down(struct tipc_node *n, int bearer_id) |
| { |
| int *slot0 = &n->active_links[0]; |
| int *slot1 = &n->active_links[1]; |
| int i, highest = 0; |
| struct tipc_link *l, *_l; |
| |
| l = n->links[bearer_id].link; |
| n->working_links--; |
| n->action_flags |= TIPC_NOTIFY_LINK_DOWN; |
| n->link_id = l->peer_bearer_id << 16 | l->bearer_id; |
| |
| pr_debug("Lost link <%s> on network plane %c\n", |
| l->name, l->net_plane); |
| |
| /* Select new active link if any available */ |
| *slot0 = INVALID_BEARER_ID; |
| *slot1 = INVALID_BEARER_ID; |
| for (i = 0; i < MAX_BEARERS; i++) { |
| _l = n->links[i].link; |
| if (!_l || !tipc_link_is_up(_l)) |
| continue; |
| if (_l->priority < highest) |
| continue; |
| if (_l->priority > highest) { |
| highest = _l->priority; |
| *slot0 = i; |
| *slot1 = i; |
| continue; |
| } |
| *slot1 = i; |
| } |
| if (tipc_node_is_up(n)) |
| tipc_link_failover_send_queue(l); |
| else |
| node_lost_contact(n); |
| } |
| |
| bool tipc_node_is_up(struct tipc_node *n) |
| { |
| return n->active_links[0] != INVALID_BEARER_ID; |
| } |
| |
| void tipc_node_check_dest(struct tipc_node *n, struct tipc_bearer *b, |
| bool *link_up, bool *addr_match, |
| struct tipc_media_addr *maddr) |
| { |
| struct tipc_link *l = n->links[b->identity].link; |
| struct tipc_media_addr *curr = &n->links[b->identity].maddr; |
| |
| *link_up = l && tipc_link_is_up(l); |
| *addr_match = l && !memcmp(curr, maddr, sizeof(*maddr)); |
| } |
| |
| bool tipc_node_update_dest(struct tipc_node *n, struct tipc_bearer *b, |
| struct tipc_media_addr *maddr) |
| { |
| struct tipc_link *l = n->links[b->identity].link; |
| struct tipc_media_addr *curr = &n->links[b->identity].maddr; |
| struct sk_buff_head *inputq = &n->links[b->identity].inputq; |
| |
| if (!l) { |
| l = tipc_link_create(n, b, maddr, inputq, &n->bclink.namedq); |
| if (!l) |
| return false; |
| tipc_node_calculate_timer(n, l); |
| if (n->link_cnt == 1) { |
| if (!mod_timer(&n->timer, jiffies + n->keepalive_intv)) |
| tipc_node_get(n); |
| } |
| } |
| memcpy(&l->media_addr, maddr, sizeof(*maddr)); |
| memcpy(curr, maddr, sizeof(*maddr)); |
| tipc_link_reset(l); |
| return true; |
| } |
| |
| void tipc_node_attach_link(struct tipc_node *n_ptr, struct tipc_link *l_ptr) |
| { |
| n_ptr->links[l_ptr->bearer_id].link = 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].link) |
| continue; |
| n_ptr->links[i].link = NULL; |
| n_ptr->link_cnt--; |
| } |
| } |
| |
| /* tipc_node_fsm_evt - node finite state machine |
| * Determines when contact is allowed with peer node |
| */ |
| static void tipc_node_fsm_evt(struct tipc_node *n, int evt) |
| { |
| int state = n->state; |
| |
| switch (state) { |
| case SELF_DOWN_PEER_DOWN: |
| switch (evt) { |
| case SELF_ESTABL_CONTACT_EVT: |
| state = SELF_UP_PEER_COMING; |
| break; |
| case PEER_ESTABL_CONTACT_EVT: |
| state = SELF_COMING_PEER_UP; |
| break; |
| case SELF_LOST_CONTACT_EVT: |
| case PEER_LOST_CONTACT_EVT: |
| break; |
| default: |
| pr_err("Unknown node fsm evt %x/%x\n", state, evt); |
| } |
| break; |
| case SELF_UP_PEER_UP: |
| switch (evt) { |
| case SELF_LOST_CONTACT_EVT: |
| state = SELF_DOWN_PEER_LEAVING; |
| break; |
| case PEER_LOST_CONTACT_EVT: |
| state = SELF_LEAVING_PEER_DOWN; |
| break; |
| case SELF_ESTABL_CONTACT_EVT: |
| case PEER_ESTABL_CONTACT_EVT: |
| break; |
| default: |
| pr_err("Unknown node fsm evt %x/%x\n", state, evt); |
| } |
| break; |
| case SELF_DOWN_PEER_LEAVING: |
| switch (evt) { |
| case PEER_LOST_CONTACT_EVT: |
| state = SELF_DOWN_PEER_DOWN; |
| break; |
| case SELF_ESTABL_CONTACT_EVT: |
| case PEER_ESTABL_CONTACT_EVT: |
| case SELF_LOST_CONTACT_EVT: |
| break; |
| default: |
| pr_err("Unknown node fsm evt %x/%x\n", state, evt); |
| } |
| break; |
| case SELF_UP_PEER_COMING: |
| switch (evt) { |
| case PEER_ESTABL_CONTACT_EVT: |
| state = SELF_UP_PEER_UP; |
| break; |
| case SELF_LOST_CONTACT_EVT: |
| state = SELF_DOWN_PEER_LEAVING; |
| break; |
| case SELF_ESTABL_CONTACT_EVT: |
| case PEER_LOST_CONTACT_EVT: |
| break; |
| default: |
| pr_err("Unknown node fsm evt %x/%x\n", state, evt); |
| } |
| break; |
| case SELF_COMING_PEER_UP: |
| switch (evt) { |
| case SELF_ESTABL_CONTACT_EVT: |
| state = SELF_UP_PEER_UP; |
| break; |
| case PEER_LOST_CONTACT_EVT: |
| state = SELF_LEAVING_PEER_DOWN; |
| break; |
| case SELF_LOST_CONTACT_EVT: |
| case PEER_ESTABL_CONTACT_EVT: |
| break; |
| default: |
| pr_err("Unknown node fsm evt %x/%x\n", state, evt); |
| } |
| break; |
| case SELF_LEAVING_PEER_DOWN: |
| switch (evt) { |
| case SELF_LOST_CONTACT_EVT: |
| state = SELF_DOWN_PEER_DOWN; |
| break; |
| case SELF_ESTABL_CONTACT_EVT: |
| case PEER_ESTABL_CONTACT_EVT: |
| case PEER_LOST_CONTACT_EVT: |
| break; |
| default: |
| pr_err("Unknown node fsm evt %x/%x\n", state, evt); |
| } |
| break; |
| default: |
| pr_err("Unknown node fsm state %x\n", state); |
| break; |
| } |
| |
| n->state = state; |
| } |
| |
| bool tipc_node_filter_skb(struct tipc_node *n, struct tipc_link *l, |
| struct tipc_msg *hdr) |
| { |
| int state = n->state; |
| |
| if (likely(state == SELF_UP_PEER_UP)) |
| return true; |
| |
| if (state == SELF_DOWN_PEER_DOWN) |
| return true; |
| |
| if (state == SELF_UP_PEER_COMING) { |
| /* If not traffic msg, peer may still be ESTABLISHING */ |
| if (tipc_link_is_up(l) && msg_is_traffic(hdr)) |
| tipc_node_fsm_evt(n, PEER_ESTABL_CONTACT_EVT); |
| return true; |
| } |
| |
| if (state == SELF_COMING_PEER_UP) |
| return true; |
| |
| if (state == SELF_LEAVING_PEER_DOWN) |
| return false; |
| |
| if (state == SELF_DOWN_PEER_LEAVING) { |
| if (msg_peer_is_up(hdr)) |
| return false; |
| tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT); |
| return true; |
| } |
| return false; |
| } |
| |
| static void node_established_contact(struct tipc_node *n_ptr) |
| { |
| tipc_node_fsm_evt(n_ptr, SELF_ESTABL_CONTACT_EVT); |
| 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].link; |
| if (!l_ptr) |
| continue; |
| l_ptr->exec_mode = TIPC_LINK_OPEN; |
| 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); |
| } |
| /* Prevent re-contact with node until cleanup is done */ |
| tipc_node_fsm_evt(n_ptr, SELF_LOST_CONTACT_EVT); |
| |
| /* 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].link; |
| 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; |
| } |
| |
| static struct tipc_link *tipc_node_select_link(struct tipc_node *n, int sel, |
| int *bearer_id, |
| struct tipc_media_addr **maddr) |
| { |
| int id = n->active_links[sel & 1]; |
| |
| if (unlikely(id < 0)) |
| return NULL; |
| |
| *bearer_id = id; |
| *maddr = &n->links[id].maddr; |
| return n->links[id].link; |
| } |
| |
| /** |
| * tipc_node_xmit() is the general link level function for message sending |
| * @net: the applicable net namespace |
| * @list: chain of buffers containing message |
| * @dnode: address of destination node |
| * @selector: a number used for deterministic link selection |
| * Consumes the buffer chain, except when returning -ELINKCONG |
| * Returns 0 if success, otherwise errno: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE |
| */ |
| int tipc_node_xmit(struct net *net, struct sk_buff_head *list, |
| u32 dnode, int selector) |
| { |
| struct tipc_link *l = NULL; |
| struct tipc_node *n; |
| struct sk_buff_head xmitq; |
| struct tipc_media_addr *maddr; |
| int bearer_id; |
| int rc = -EHOSTUNREACH; |
| |
| __skb_queue_head_init(&xmitq); |
| n = tipc_node_find(net, dnode); |
| if (likely(n)) { |
| tipc_node_lock(n); |
| l = tipc_node_select_link(n, selector, &bearer_id, &maddr); |
| if (likely(l)) |
| rc = tipc_link_xmit(l, list, &xmitq); |
| if (unlikely(rc == -ENOBUFS)) |
| tipc_link_reset(l); |
| tipc_node_unlock(n); |
| tipc_node_put(n); |
| } |
| if (likely(!rc)) { |
| tipc_bearer_xmit(net, bearer_id, &xmitq, maddr); |
| return 0; |
| } |
| if (likely(in_own_node(net, dnode))) { |
| tipc_sk_rcv(net, list); |
| return 0; |
| } |
| return rc; |
| } |
| |
| /* tipc_node_xmit_skb(): send single buffer to destination |
| * Buffers sent via this functon are generally TIPC_SYSTEM_IMPORTANCE |
| * messages, which will not be rejected |
| * The only exception is datagram messages rerouted after secondary |
| * lookup, which are rare and safe to dispose of anyway. |
| * TODO: Return real return value, and let callers use |
| * tipc_wait_for_sendpkt() where applicable |
| */ |
| int tipc_node_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode, |
| u32 selector) |
| { |
| struct sk_buff_head head; |
| int rc; |
| |
| skb_queue_head_init(&head); |
| __skb_queue_tail(&head, skb); |
| rc = tipc_node_xmit(net, &head, dnode, selector); |
| if (rc == -ELINKCONG) |
| kfree_skb(skb); |
| return 0; |
| } |
| |
| /** |
| * tipc_rcv - process TIPC packets/messages arriving from off-node |
| * @net: the applicable net namespace |
| * @skb: TIPC packet |
| * @bearer: pointer to bearer message arrived on |
| * |
| * Invoked with no locks held. Bearer pointer must point to a valid bearer |
| * structure (i.e. cannot be NULL), but bearer can be inactive. |
| */ |
| void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b) |
| { |
| struct sk_buff_head xmitq; |
| struct tipc_node *n; |
| struct tipc_link *l; |
| struct tipc_msg *hdr; |
| struct tipc_media_addr *maddr; |
| int bearer_id = b->identity; |
| int rc = 0; |
| |
| __skb_queue_head_init(&xmitq); |
| |
| /* Ensure message is well-formed */ |
| if (unlikely(!tipc_msg_validate(skb))) |
| goto discard; |
| |
| /* Handle arrival of a non-unicast link packet */ |
| hdr = buf_msg(skb); |
| if (unlikely(msg_non_seq(hdr))) { |
| if (msg_user(hdr) == LINK_CONFIG) |
| tipc_disc_rcv(net, skb, b); |
| else |
| tipc_bclink_rcv(net, skb); |
| return; |
| } |
| |
| /* Locate neighboring node that sent packet */ |
| n = tipc_node_find(net, msg_prevnode(hdr)); |
| if (unlikely(!n)) |
| goto discard; |
| tipc_node_lock(n); |
| |
| /* Locate link endpoint that should handle packet */ |
| l = n->links[bearer_id].link; |
| if (unlikely(!l)) |
| goto unlock; |
| |
| /* Is reception of this packet permitted at the moment ? */ |
| if (unlikely(n->state != SELF_UP_PEER_UP)) |
| if (!tipc_node_filter_skb(n, l, hdr)) |
| goto unlock; |
| |
| if (unlikely(msg_user(hdr) == LINK_PROTOCOL)) |
| tipc_bclink_sync_state(n, hdr); |
| |
| /* Release acked broadcast messages */ |
| if (unlikely(n->bclink.acked != msg_bcast_ack(hdr))) |
| tipc_bclink_acknowledge(n, msg_bcast_ack(hdr)); |
| |
| /* Check protocol and update link state */ |
| rc = tipc_link_rcv(l, skb, &xmitq); |
| |
| if (unlikely(rc & TIPC_LINK_UP_EVT)) |
| tipc_node_link_up(n, bearer_id); |
| if (unlikely(rc & TIPC_LINK_DOWN_EVT)) |
| tipc_link_reset(l); |
| skb = NULL; |
| unlock: |
| tipc_node_unlock(n); |
| tipc_sk_rcv(net, &n->links[bearer_id].inputq); |
| maddr = &n->links[bearer_id].maddr; |
| tipc_bearer_xmit(net, bearer_id, &xmitq, maddr); |
| tipc_node_put(n); |
| discard: |
| kfree_skb(skb); |
| } |
| |
| 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; |
| } |