diff options
Diffstat (limited to 'net/tipc/node.c')
| -rw-r--r-- | net/tipc/node.c | 1402 |
1 files changed, 1402 insertions, 0 deletions
diff --git a/net/tipc/node.c b/net/tipc/node.c new file mode 100644 index 000000000000..2df0b98d4a32 --- /dev/null +++ b/net/tipc/node.c @@ -0,0 +1,1402 @@ +/* + * 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" + +/* Node FSM states and events: + */ +enum { + SELF_DOWN_PEER_DOWN = 0xdd, + SELF_UP_PEER_UP = 0xaa, + SELF_DOWN_PEER_LEAVING = 0xd1, + SELF_UP_PEER_COMING = 0xac, + SELF_COMING_PEER_UP = 0xca, + SELF_LEAVING_PEER_DOWN = 0x1d, + NODE_FAILINGOVER = 0xf0, + NODE_SYNCHING = 0xcc +}; + +enum { + SELF_ESTABL_CONTACT_EVT = 0xece, + SELF_LOST_CONTACT_EVT = 0x1ce, + PEER_ESTABL_CONTACT_EVT = 0x9ece, + PEER_LOST_CONTACT_EVT = 0x91ce, + NODE_FAILOVER_BEGIN_EVT = 0xfbe, + NODE_FAILOVER_END_EVT = 0xfee, + NODE_SYNCH_BEGIN_EVT = 0xcbe, + NODE_SYNCH_END_EVT = 0xcee +}; + +static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id, + struct sk_buff_head *xmitq, + struct tipc_media_addr **maddr); +static void tipc_node_link_down(struct tipc_node *n, int bearer_id, + bool delete); +static void node_lost_contact(struct tipc_node *n, struct sk_buff_head *inputq); +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 *n = container_of(kref, struct tipc_node, kref); + + kfree(n->bc_entry.link); + kfree_rcu(n, rcu); +} + +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, u16 capabilities) +{ + 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; + n_ptr->capabilities = capabilities; + 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->bc_entry.namedq); + skb_queue_head_init(&n_ptr->bc_entry.inputq1); + __skb_queue_head_init(&n_ptr->bc_entry.arrvq); + skb_queue_head_init(&n_ptr->bc_entry.inputq2); + 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; + if (!tipc_link_bc_create(net, tipc_own_addr(net), n_ptr->addr, + U16_MAX, tipc_bc_sndlink(net)->window, + n_ptr->capabilities, + &n_ptr->bc_entry.inputq1, + &n_ptr->bc_entry.namedq, + tipc_bc_sndlink(net), + &n_ptr->bc_entry.link)) { + pr_warn("Broadcast rcv link creation failed, no memory\n"); + kfree(n_ptr); + n_ptr = NULL; + goto exit; + } + tipc_node_get(n_ptr); + setup_timer(&n_ptr->timer, tipc_node_timeout, (unsigned long)n_ptr); + n_ptr->keepalive_intv = U32_MAX; + 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); +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); + tipc_node_put(node); + + del_timer_sync(&node->timer); + tipc_node_put(node); +} + +void tipc_node_stop(struct net *net) +{ + struct tipc_net *tn = tipc_net(net); + 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_delete(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 tipc_link_entry *le; + struct sk_buff_head xmitq; + 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); + le = &n->links[bearer_id]; + if (le->link) { + /* Link tolerance may change asynchronously: */ + tipc_node_calculate_timer(n, le->link); + rc = tipc_link_timeout(le->link, &xmitq); + } + tipc_node_unlock(n); + tipc_bearer_xmit(n->net, bearer_id, &xmitq, &le->maddr); + if (rc & TIPC_LINK_DOWN_EVT) + tipc_node_link_down(n, bearer_id, false); + } + mod_timer(&n->timer, jiffies + n->keepalive_intv); +} + +/** + * __tipc_node_link_up - handle addition of link + * Node lock must be held by caller + * Link becomes active (alone or shared) or standby, depending on its priority. + */ +static void __tipc_node_link_up(struct tipc_node *n, int bearer_id, + struct sk_buff_head *xmitq) +{ + int *slot0 = &n->active_links[0]; + int *slot1 = &n->active_links[1]; + struct tipc_link *ol = node_active_link(n, 0); + struct tipc_link *nl = n->links[bearer_id].link; + + if (!nl) + return; + + tipc_link_fsm_evt(nl, LINK_ESTABLISH_EVT); + if (!tipc_link_is_up(nl)) + return; + + n->working_links++; + n->action_flags |= TIPC_NOTIFY_LINK_UP; + n->link_id = nl->peer_bearer_id << 16 | bearer_id; + + /* Leave room for tunnel header when returning 'mtu' to users: */ + n->links[bearer_id].mtu = nl->mtu - INT_H_SIZE; + + tipc_bearer_add_dest(n->net, bearer_id, n->addr); + tipc_bcast_inc_bearer_dst_cnt(n->net, bearer_id); + + pr_debug("Established link <%s> on network plane %c\n", + nl->name, nl->net_plane); + + /* First link? => give it both slots */ + if (!ol) { + *slot0 = bearer_id; + *slot1 = bearer_id; + tipc_node_fsm_evt(n, SELF_ESTABL_CONTACT_EVT); + n->action_flags |= TIPC_NOTIFY_NODE_UP; + tipc_bcast_add_peer(n->net, nl, xmitq); + return; + } + + /* Second link => redistribute slots */ + if (nl->priority > ol->priority) { + pr_debug("Old link <%s> becomes standby\n", ol->name); + *slot0 = bearer_id; + *slot1 = bearer_id; + tipc_link_set_active(nl, true); + tipc_link_set_active(ol, false); + } else if (nl->priority == ol->priority) { + tipc_link_set_active(nl, true); + *slot1 = bearer_id; + } else { + pr_debug("New link <%s> is standby\n", nl->name); + } + + /* Prepare synchronization with first link */ + tipc_link_tnl_prepare(ol, nl, SYNCH_MSG, xmitq); +} + +/** + * tipc_node_link_up - handle addition of link + * + * Link becomes active (alone or shared) or standby, depending on its priority. + */ +static void tipc_node_link_up(struct tipc_node *n, int bearer_id, + struct sk_buff_head *xmitq) +{ + tipc_node_lock(n); + __tipc_node_link_up(n, bearer_id, xmitq); + tipc_node_unlock(n); +} + +/** + * __tipc_node_link_down - handle loss of link + */ +static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id, + struct sk_buff_head *xmitq, + struct tipc_media_addr **maddr) +{ + struct tipc_link_entry *le = &n->links[*bearer_id]; + int *slot0 = &n->active_links[0]; + int *slot1 = &n->active_links[1]; + int i, highest = 0; + struct tipc_link *l, *_l, *tnl; + + l = n->links[*bearer_id].link; + if (!l || tipc_link_is_reset(l)) + return; + + n->working_links--; + n->action_flags |= TIPC_NOTIFY_LINK_DOWN; + n->link_id = l->peer_bearer_id << 16 | *bearer_id; + + tipc_bearer_remove_dest(n->net, *bearer_id, n->addr); + + 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 == 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)) { + if (tipc_link_peer_is_down(l)) + tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT); + tipc_node_fsm_evt(n, SELF_LOST_CONTACT_EVT); + tipc_link_fsm_evt(l, LINK_RESET_EVT); + tipc_link_reset(l); + tipc_link_build_reset_msg(l, xmitq); + *maddr = &n->links[*bearer_id].maddr; + node_lost_contact(n, &le->inputq); + tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id); + return; + } + tipc_bcast_dec_bearer_dst_cnt(n->net, *bearer_id); + + /* There is still a working link => initiate failover */ + tnl = node_active_link(n, 0); + tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT); + tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT); + n->sync_point = tnl->rcv_nxt + (U16_MAX / 2 - 1); + tipc_link_tnl_prepare(l, tnl, FAILOVER_MSG, xmitq); + tipc_link_reset(l); + tipc_link_fsm_evt(l, LINK_RESET_EVT); + tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT); + tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT); + *maddr = &n->links[tnl->bearer_id].maddr; + *bearer_id = tnl->bearer_id; +} + +static void tipc_node_link_down(struct tipc_node *n, int bearer_id, bool delete) +{ + struct tipc_link_entry *le = &n->links[bearer_id]; + struct tipc_link *l = le->link; + struct tipc_media_addr *maddr; + struct sk_buff_head xmitq; + + if (!l) + return; + + __skb_queue_head_init(&xmitq); + + tipc_node_lock(n); + if (!tipc_link_is_establishing(l)) { + __tipc_node_link_down(n, &bearer_id, &xmitq, &maddr); + if (delete) { + kfree(l); + le->link = NULL; + n->link_cnt--; + } + } else { + /* Defuse pending tipc_node_link_up() */ + tipc_link_fsm_evt(l, LINK_RESET_EVT); + } + tipc_node_unlock(n); + tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr); + tipc_sk_rcv(n->net, &le->inputq); +} + +bool tipc_node_is_up(struct tipc_node *n) +{ + return n->active_links[0] != INVALID_BEARER_ID; +} + +void tipc_node_check_dest(struct net *net, u32 onode, + struct tipc_bearer *b, + u16 capabilities, u32 signature, + struct tipc_media_addr *maddr, + bool *respond, bool *dupl_addr) +{ + struct tipc_node *n; + struct tipc_link *l; + struct tipc_link_entry *le; + bool addr_match = false; + bool sign_match = false; + bool link_up = false; + bool accept_addr = false; + bool reset = true; + char *if_name; + + *dupl_addr = false; + *respond = false; + + n = tipc_node_create(net, onode, capabilities); + if (!n) + return; + + tipc_node_lock(n); + + le = &n->links[b->identity]; + + /* Prepare to validate requesting node's signature and media address */ + l = le->link; + link_up = l && tipc_link_is_up(l); + addr_match = l && !memcmp(&le->maddr, maddr, sizeof(*maddr)); + sign_match = (signature == n->signature); + + /* These three flags give us eight permutations: */ + + if (sign_match && addr_match && link_up) { + /* All is fine. Do nothing. */ + reset = false; + } else if (sign_match && addr_match && !link_up) { + /* Respond. The link will come up in due time */ + *respond = true; + } else if (sign_match && !addr_match && link_up) { + /* Peer has changed i/f address without rebooting. + * If so, the link will reset soon, and the next + * discovery will be accepted. So we can ignore it. + * It may also be an cloned or malicious peer having + * chosen the same node address and signature as an + * existing one. + * Ignore requests until the link goes down, if ever. + */ + *dupl_addr = true; + } else if (sign_match && !addr_match && !link_up) { + /* Peer link has changed i/f address without rebooting. + * It may also be a cloned or malicious peer; we can't + * distinguish between the two. + * The signature is correct, so we must accept. + */ + accept_addr = true; + *respond = true; + } else if (!sign_match && addr_match && link_up) { + /* Peer node rebooted. Two possibilities: + * - Delayed re-discovery; this link endpoint has already + * reset and re-established contact with the peer, before + * receiving a discovery message from that node. + * (The peer happened to receive one from this node first). + * - The peer came back so fast that our side has not + * discovered it yet. Probing from this side will soon + * reset the link, since there can be no working link + * endpoint at the peer end, and the link will re-establish. + * Accept the signature, since it comes from a known peer. + */ + n->signature = signature; + } else if (!sign_match && addr_match && !link_up) { + /* The peer node has rebooted. + * Accept signature, since it is a known peer. + */ + n->signature = signature; + *respond = true; + } else if (!sign_match && !addr_match && link_up) { + /* Peer rebooted with new address, or a new/duplicate peer. + * Ignore until the link goes down, if ever. + */ + *dupl_addr = true; + } else if (!sign_match && !addr_match && !link_up) { + /* Peer rebooted with new address, or it is a new peer. + * Accept signature and address. + */ + n->signature = signature; + accept_addr = true; + *respond = true; + } + + if (!accept_addr) + goto exit; + + /* Now create new link if not already existing */ + if (!l) { + if (n->link_cnt == 2) { + pr_warn("Cannot establish 3rd link to %x\n", n->addr); + goto exit; + } + if_name = strchr(b->name, ':') + 1; + if (!tipc_link_create(net, if_name, b->identity, b->tolerance, + b->net_plane, b->mtu, b->priority, + b->window, mod(tipc_net(net)->random), + tipc_own_addr(net), onode, + n->capabilities, + tipc_bc_sndlink(n->net), n->bc_entry.link, + &le->inputq, + &n->bc_entry.namedq, &l)) { + *respond = false; + goto exit; + } + tipc_link_reset(l); + tipc_link_fsm_evt(l, LINK_RESET_EVT); + if (n->state == NODE_FAILINGOVER) + tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT); + le->link = l; + n->link_cnt++; + 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(&le->maddr, maddr, sizeof(*maddr)); +exit: + tipc_node_unlock(n); + if (reset && !tipc_link_is_reset(l)) + tipc_node_link_down(n, b->identity, false); + tipc_node_put(n); +} + +void tipc_node_delete_links(struct net *net, int bearer_id) +{ + struct tipc_net *tn = net_generic(net, tipc_net_id); + struct tipc_node *n; + + rcu_read_lock(); + list_for_each_entry_rcu(n, &tn->node_list, list) { + tipc_node_link_down(n, bearer_id, true); + } + rcu_read_unlock(); +} + +static void tipc_node_reset_links(struct tipc_node *n) +{ + char addr_string[16]; + int i; + + pr_warn("Resetting all links to %s\n", + tipc_addr_string_fill(addr_string, n->addr)); + + for (i = 0; i < MAX_BEARERS; i++) { + tipc_node_link_down(n, i, false); + } +} + +/* 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; + case NODE_SYNCH_END_EVT: + case NODE_SYNCH_BEGIN_EVT: + case NODE_FAILOVER_BEGIN_EVT: + case NODE_FAILOVER_END_EVT: + default: + goto illegal_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 NODE_SYNCH_BEGIN_EVT: + state = NODE_SYNCHING; + break; + case NODE_FAILOVER_BEGIN_EVT: + state = NODE_FAILINGOVER; + break; + case SELF_ESTABL_CONTACT_EVT: + case PEER_ESTABL_CONTACT_EVT: + case NODE_SYNCH_END_EVT: + case NODE_FAILOVER_END_EVT: + break; + default: + goto illegal_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; + case NODE_SYNCH_END_EVT: + case NODE_SYNCH_BEGIN_EVT: + case NODE_FAILOVER_BEGIN_EVT: + case NODE_FAILOVER_END_EVT: + default: + goto illegal_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_DOWN; + break; + case SELF_ESTABL_CONTACT_EVT: + case PEER_LOST_CONTACT_EVT: + case NODE_SYNCH_END_EVT: + case NODE_FAILOVER_BEGIN_EVT: + break; + case NODE_SYNCH_BEGIN_EVT: + case NODE_FAILOVER_END_EVT: + default: + goto illegal_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_DOWN_PEER_DOWN; + break; + case SELF_LOST_CONTACT_EVT: + case PEER_ESTABL_CONTACT_EVT: + break; + case NODE_SYNCH_END_EVT: + case NODE_SYNCH_BEGIN_EVT: + case NODE_FAILOVER_BEGIN_EVT: + case NODE_FAILOVER_END_EVT: + default: + goto illegal_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; + case NODE_SYNCH_END_EVT: + case NODE_SYNCH_BEGIN_EVT: + case NODE_FAILOVER_BEGIN_EVT: + case NODE_FAILOVER_END_EVT: + default: + goto illegal_evt; + } + break; + case NODE_FAILINGOVER: + 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 NODE_FAILOVER_END_EVT: + state = SELF_UP_PEER_UP; + break; + case NODE_FAILOVER_BEGIN_EVT: + case SELF_ESTABL_CONTACT_EVT: + case PEER_ESTABL_CONTACT_EVT: + break; + case NODE_SYNCH_BEGIN_EVT: + case NODE_SYNCH_END_EVT: + default: + goto illegal_evt; + } + break; + case NODE_SYNCHING: + 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 NODE_SYNCH_END_EVT: + state = SELF_UP_PEER_UP; + break; + case NODE_FAILOVER_BEGIN_EVT: + state = NODE_FAILINGOVER; + break; + case NODE_SYNCH_BEGIN_EVT: + case SELF_ESTABL_CONTACT_EVT: + case PEER_ESTABL_CONTACT_EVT: + break; + case NODE_FAILOVER_END_EVT: + default: + goto illegal_evt; + } + break; + default: + pr_err("Unknown node fsm state %x\n", state); + break; + } + n->state = state; + return; + +illegal_evt: + pr_err("Illegal node fsm evt %x in state %x\n", evt, state); +} + +bool tipc_node_filter_pkt(struct tipc_node *n, struct tipc_msg *hdr) +{ + int state = n->state; + + if (likely(state == SELF_UP_PEER_UP)) + return true; + + if (state == SELF_LEAVING_PEER_DOWN) + return false; + + if (state == SELF_DOWN_PEER_LEAVING) { + if (msg_peer_node_is_up(hdr)) + return false; + } + + return true; +} + +static void node_lost_contact(struct tipc_node *n, + struct sk_buff_head *inputq) +{ + char addr_string[16]; + struct tipc_sock_conn *conn, *safe; + struct tipc_link *l; + struct list_head *conns = &n->conn_sks; + struct sk_buff *skb; + uint i; + + pr_debug("Lost contact with %s\n", + tipc_addr_string_fill(addr_string, n->addr)); + + /* Clean up broadcast state */ + tipc_bcast_remove_peer(n->net, n->bc_entry.link); + + /* Abort any ongoing link failover */ + for (i = 0; i < MAX_BEARERS; i++) { + l = n->links[i].link; + if (l) + tipc_link_fsm_evt(l, LINK_FAILOVER_END_EVT); + } + + /* Notify publications from this node */ + n->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, tipc_own_addr(n->net), + conn->peer_node, conn->port, + conn->peer_port, TIPC_ERR_NO_NODE); + if (likely(skb)) + skb_queue_tail(inputq, skb); + 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; + + if (likely(!flags)) { + spin_unlock_bh(&node->lock); + return; + } + + addr = node->addr; + link_id = node->link_id; + publ_list = &node->publ_list; + + node->action_flags &= ~(TIPC_NOTIFY_NODE_DOWN | TIPC_NOTIFY_NODE_UP | + TIPC_NOTIFY_LINK_DOWN | TIPC_NOTIFY_LINK_UP); + + spin_unlock_bh(&node->lock); + + if (flags & TIPC_NOTIFY_NODE_DOWN) + tipc_publ_notify(net, publ_list, addr); + + 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); + +} + +/* 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); + tipc_node_unlock(n); + if (unlikely(rc == -ENOBUFS)) + tipc_node_link_down(n, bearer_id, false); + 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_node_bc_rcv - process TIPC broadcast packet arriving from off-node + * @net: the applicable net namespace + * @skb: TIPC packet + * @bearer_id: id of bearer message arrived on + * + * Invoked with no locks held. + */ +static void tipc_node_bc_rcv(struct net *net, struct sk_buff *skb, int bearer_id) +{ + int rc; + struct sk_buff_head xmitq; + struct tipc_bclink_entry *be; + struct tipc_link_entry *le; + struct tipc_msg *hdr = buf_msg(skb); + int usr = msg_user(hdr); + u32 dnode = msg_destnode(hdr); + struct tipc_node *n; + + __skb_queue_head_init(&xmitq); + + /* If NACK for other node, let rcv link for that node peek into it */ + if ((usr == BCAST_PROTOCOL) && (dnode != tipc_own_addr(net))) + n = tipc_node_find(net, dnode); + else + n = tipc_node_find(net, msg_prevnode(hdr)); + if (!n) { + kfree_skb(skb); + return; + } + be = &n->bc_entry; + le = &n->links[bearer_id]; + + rc = tipc_bcast_rcv(net, be->link, skb); + + /* Broadcast link reset may happen at reassembly failure */ + if (rc & TIPC_LINK_DOWN_EVT) + tipc_node_reset_links(n); + + /* Broadcast ACKs are sent on a unicast link */ + if (rc & TIPC_LINK_SND_BC_ACK) { + tipc_node_lock(n); + tipc_link_build_ack_msg(le->link, &xmitq); + tipc_node_unlock(n); + } + + if (!skb_queue_empty(&xmitq)) + tipc_bearer_xmit(net, bearer_id, &xmitq, &le->maddr); + + /* Deliver. 'arrvq' is under inputq2's lock protection */ + if (!skb_queue_empty(&be->inputq1)) { + spin_lock_bh(&be->inputq2.lock); + spin_lock_bh(&be->inputq1.lock); + skb_queue_splice_tail_init(&be->inputq1, &be->arrvq); + spin_unlock_bh(&be->inputq1.lock); + spin_unlock_bh(&be->inputq2.lock); + tipc_sk_mcast_rcv(net, &be->arrvq, &be->inputq2); + } + tipc_node_put(n); +} + +/** + * tipc_node_check_state - check and if necessary update node state + * @skb: TIPC packet + * @bearer_id: identity of bearer delivering the packet + * Returns true if state is ok, otherwise consumes buffer and returns false + */ +static bool tipc_node_check_state(struct tipc_node *n, struct sk_buff *skb, + int bearer_id, struct sk_buff_head *xmitq) +{ + struct tipc_msg *hdr = buf_msg(skb); + int usr = msg_user(hdr); + int mtyp = msg_type(hdr); + u16 oseqno = msg_seqno(hdr); + u16 iseqno = msg_seqno(msg_get_wrapped(hdr)); + u16 exp_pkts = msg_msgcnt(hdr); + u16 rcv_nxt, syncpt, dlv_nxt; + int state = n->state; + struct tipc_link *l, *tnl, *pl = NULL; + struct tipc_media_addr *maddr; + int i, pb_id; + + l = n->links[bearer_id].link; + if (!l) + return false; + rcv_nxt = l->rcv_nxt; + + + if (likely((state == SELF_UP_PEER_UP) && (usr != TUNNEL_PROTOCOL))) + return true; + + /* Find parallel link, if any */ + for (i = 0; i < MAX_BEARERS; i++) { + if ((i != bearer_id) && n->links[i].link) { + pl = n->links[i].link; + break; + } + } + + /* Update node accesibility if applicable */ + if (state == SELF_UP_PEER_COMING) { + if (!tipc_link_is_up(l)) + return true; + if (!msg_peer_link_is_up(hdr)) + return true; + tipc_node_fsm_evt(n, PEER_ESTABL_CONTACT_EVT); + } + + if (state == SELF_DOWN_PEER_LEAVING) { + if (msg_peer_node_is_up(hdr)) + return false; + tipc_node_fsm_evt(n, PEER_LOST_CONTACT_EVT); + } + + /* Ignore duplicate packets */ + if ((usr != LINK_PROTOCOL) && less(oseqno, rcv_nxt)) + return true; + + /* Initiate or update failover mode if applicable */ + if ((usr == TUNNEL_PROTOCOL) && (mtyp == FAILOVER_MSG)) { + syncpt = oseqno + exp_pkts - 1; + if (pl && tipc_link_is_up(pl)) { + pb_id = pl->bearer_id; + __tipc_node_link_down(n, &pb_id, xmitq, &maddr); + tipc_skb_queue_splice_tail_init(pl->inputq, l->inputq); + } + /* If pkts arrive out of order, use lowest calculated syncpt */ + if (less(syncpt, n->sync_point)) + n->sync_point = syncpt; + } + + /* Open parallel link when tunnel link reaches synch point */ + if ((n->state == NODE_FAILINGOVER) && tipc_link_is_up(l)) { + if (!more(rcv_nxt, n->sync_point)) + return true; + tipc_node_fsm_evt(n, NODE_FAILOVER_END_EVT); + if (pl) + tipc_link_fsm_evt(pl, LINK_FAILOVER_END_EVT); + return true; + } + + /* No synching needed if only one link */ + if (!pl || !tipc_link_is_up(pl)) + return true; + + /* Initiate synch mode if applicable */ + if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG) && (oseqno == 1)) { + syncpt = iseqno + exp_pkts - 1; + if (!tipc_link_is_up(l)) { + tipc_link_fsm_evt(l, LINK_ESTABLISH_EVT); + __tipc_node_link_up(n, bearer_id, xmitq); + } + if (n->state == SELF_UP_PEER_UP) { + n->sync_point = syncpt; + tipc_link_fsm_evt(l, LINK_SYNCH_BEGIN_EVT); + tipc_node_fsm_evt(n, NODE_SYNCH_BEGIN_EVT); + } + if (less(syncpt, n->sync_point)) + n->sync_point = syncpt; + } + + /* Open tunnel link when parallel link reaches synch point */ + if ((n->state == NODE_SYNCHING) && tipc_link_is_synching(l)) { + if (tipc_link_is_synching(l)) { + tnl = l; + } else { + tnl = pl; + pl = l; + } + dlv_nxt = pl->rcv_nxt - mod(skb_queue_len(pl->inputq)); + if (more(dlv_nxt, n->sync_point)) { + tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT); + tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT); + return true; + } + if (l == pl) + return true; + if ((usr == TUNNEL_PROTOCOL) && (mtyp == SYNCH_MSG)) + return true; + if (usr == LINK_PROTOCOL) + return true; + return false; + } + return true; +} + +/** + * 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_msg *hdr = buf_msg(skb); + int usr = msg_user(hdr); + int bearer_id = b->identity; + struct tipc_link_entry *le; + u16 bc_ack = msg_bcast_ack(hdr); + int rc = 0; + + __skb_queue_head_init(&xmitq); + + /* Ensure message is well-formed */ + if (unlikely(!tipc_msg_validate(skb))) + goto discard; + + /* Handle arrival of discovery or broadcast packet */ + if (unlikely(msg_non_seq(hdr))) { + if (unlikely(usr == LINK_CONFIG)) + return tipc_disc_rcv(net, skb, b); + else + return tipc_node_bc_rcv(net, skb, bearer_id); + } + + /* Locate neighboring node that sent packet */ + n = tipc_node_find(net, msg_prevnode(hdr)); + if (unlikely(!n)) + goto discard; + le = &n->links[bearer_id]; + + /* Ensure broadcast reception is in synch with peer's send state */ + if (unlikely(usr == LINK_PROTOCOL)) + tipc_bcast_sync_rcv(net, n->bc_entry.link, hdr); + else if (unlikely(n->bc_entry.link->acked != bc_ack)) + tipc_bcast_ack_rcv(net, n->bc_entry.link, bc_ack); + + tipc_node_lock(n); + + /* Is reception permitted at the moment ? */ + if (!tipc_node_filter_pkt(n, hdr)) + goto unlock; + + /* Check and if necessary update node state */ + if (likely(tipc_node_check_state(n, skb, bearer_id, &xmitq))) { + rc = tipc_link_rcv(le->link, skb, &xmitq); + skb = NULL; + } +unlock: + tipc_node_unlock(n); + + if (unlikely(rc & TIPC_LINK_UP_EVT)) + tipc_node_link_up(n, bearer_id, &xmitq); + + if (unlikely(rc & TIPC_LINK_DOWN_EVT)) + tipc_node_link_down(n, bearer_id, false); + + if (unlikely(!skb_queue_empty(&n->bc_entry.namedq))) + tipc_named_rcv(net, &n->bc_entry.namedq); + + if (!skb_queue_empty(&le->inputq)) + tipc_sk_rcv(net, &le->inputq); + + if (!skb_queue_empty(&xmitq)) + tipc_bearer_xmit(net, bearer_id, &xmitq, &le->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; +} |