/*
* net/tipc/link.c: TIPC link code
*
* Copyright (c) 1996-2007, 2012-2016, Ericsson AB
* Copyright (c) 2004-2007, 2010-2013, 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 "subscr.h"
#include "link.h"
#include "bcast.h"
#include "socket.h"
#include "name_distr.h"
#include "discover.h"
#include "netlink.h"
#include "monitor.h"
#include "trace.h"
#include "crypto.h"
#include <linux/pkt_sched.h>
struct tipc_stats {
u32 sent_pkts;
u32 recv_pkts;
u32 sent_states;
u32 recv_states;
u32 sent_probes;
u32 recv_probes;
u32 sent_nacks;
u32 recv_nacks;
u32 sent_acks;
u32 sent_bundled;
u32 sent_bundles;
u32 recv_bundled;
u32 recv_bundles;
u32 retransmitted;
u32 sent_fragmented;
u32 sent_fragments;
u32 recv_fragmented;
u32 recv_fragments;
u32 link_congs; /* # port sends blocked by congestion */
u32 deferred_recv;
u32 duplicates;
u32 max_queue_sz; /* send queue size high water mark */
u32 accu_queue_sz; /* used for send queue size profiling */
u32 queue_sz_counts; /* used for send queue size profiling */
u32 msg_length_counts; /* used for message length profiling */
u32 msg_lengths_total; /* used for message length profiling */
u32 msg_length_profile[7]; /* used for msg. length profiling */
};
/**
* struct tipc_link - TIPC link data structure
* @addr: network address of link's peer node
* @name: link name character string
* @net: pointer to namespace struct
* @peer_session: link session # being used by peer end of link
* @peer_bearer_id: bearer id used by link's peer endpoint
* @bearer_id: local bearer id used by link
* @tolerance: minimum link continuity loss needed to reset link [in ms]
* @abort_limit: # of unacknowledged continuity probes needed to reset link
* @state: current state of link FSM
* @peer_caps: bitmap describing capabilities of peer node
* @silent_intv_cnt: # of timer intervals without any reception from peer
* @priority: current link priority
* @net_plane: current link network plane ('A' through 'H')
* @mon_state: cookie with information needed by link monitor
* @mtu: current maximum packet size for this link
* @advertised_mtu: advertised own mtu when link is being established
* @backlogq: queue for messages waiting to be sent
* @ackers: # of peers that needs to ack each packet before it can be released
* @acked: # last packet acked by a certain peer. Used for broadcast.
* @rcv_nxt: next sequence number to expect for inbound messages
* @inputq: buffer queue for messages to be delivered upwards
* @namedq: buffer queue for name table messages to be delivered upwards
* @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
* @reasm_buf: head of partially reassembled inbound message fragments
* @stats: collects statistics regarding link activity
* @session: session to be used by link
* @snd_nxt_state: next send seq number
* @rcv_nxt_state: next rcv seq number
* @in_session: have received ACTIVATE_MSG from peer
* @active: link is active
* @if_name: associated interface name
* @rst_cnt: link reset counter
* @drop_point: seq number for failover handling (FIXME)
* @failover_reasm_skb: saved failover msg ptr (FIXME)
* @failover_deferdq: deferred message queue for failover processing (FIXME)
* @transmq: the link's transmit queue
* @backlog: link's backlog by priority (importance)
* @snd_nxt: next sequence number to be used
* @rcv_unacked: # messages read by user, but not yet acked back to peer
* @deferdq: deferred receive queue
* @window: sliding window size for congestion handling
* @min_win: minimal send window to be used by link
* @ssthresh: slow start threshold for congestion handling
* @max_win: maximal send window to be used by link
* @cong_acks: congestion acks for congestion avoidance (FIXME)
* @checkpoint: seq number for congestion window size handling
* @reasm_tnlmsg: fragmentation/reassembly area for tunnel protocol message
* @last_gap: last gap ack blocks for bcast (FIXME)
* @last_ga: ptr to gap ack blocks
* @bc_rcvlink: the peer specific link used for broadcast reception
* @bc_sndlink: the namespace global link used for broadcast sending
* @nack_state: bcast nack state
* @bc_peer_is_up: peer has acked the bcast init msg
*/
struct tipc_link {
u32 addr;
char name[TIPC_MAX_LINK_NAME];
struct net *net;
/* Management and link supervision data */
u16 peer_session;
u16 session;
u16 snd_nxt_state;
u16 rcv_nxt_state;
u32 peer_bearer_id;
u32 bearer_id;
u32 tolerance;
u32 abort_limit;
u32 state;
u16 peer_caps;
bool in_session;
bool active;
u32 silent_intv_cnt;
char if_name[TIPC_MAX_IF_NAME];
u32 priority;
char net_plane;
struct tipc_mon_state mon_state;
u16 rst_cnt;
/* Failover/synch */
u16 drop_point;
struct sk_buff *failover_reasm_skb;
struct sk_buff_head failover_deferdq;
/* Max packet negotiation */
u16 mtu;
u16 advertised_mtu;
/* Sending */
struct sk_buff_head transmq;
struct sk_buff_head backlogq;
struct {
u16 len;
u16 limit;
struct sk_buff *target_bskb;
} backlog[5];
u16 snd_nxt;
/* Reception */
u16 rcv_nxt;
u32 rcv_unacked;
struct sk_buff_head deferdq;
struct sk_buff_head *inputq;
struct sk_buff_head *namedq;
/* Congestion handling */
struct sk_buff_head wakeupq;
u16 window;
u16 min_win;
u16 ssthresh;
u16 max_win;
u16 cong_acks;
u16 checkpoint;
/* Fragmentation/reassembly */
struct sk_buff *reasm_buf;
struct sk_buff *reasm_tnlmsg;
/* Broadcast */
u16 ackers;
u16 acked;
u16 last_gap;
struct tipc_gap_ack_blks *last_ga;
struct tipc_link *bc_rcvlink;
struct tipc_link *bc_sndlink;
u8 nack_state;
bool bc_peer_is_up;
/* Statistics */
struct tipc_stats stats;
};
/*
* Error message prefixes
*/
static const char *link_co_err = "Link tunneling error, ";
static const char *link_rst_msg = "Resetting link ";
/* Send states for broadcast NACKs
*/
enum {
BC_NACK_SND_CONDITIONAL,
BC_NACK_SND_UNCONDITIONAL,
BC_NACK_SND_SUPPRESS,
};
#define TIPC_BC_RETR_LIM (jiffies + msecs_to_jiffies(10))
#define TIPC_UC_RETR_TIME (jiffies + msecs_to_jiffies(1))
/* Link FSM states:
*/
enum {
LINK_ESTABLISHED = 0xe,
LINK_ESTABLISHING = 0xe << 4,
LINK_RESET = 0x1 << 8,
LINK_RESETTING = 0x2 << 12,
LINK_PEER_RESET = 0xd << 16,
LINK_FAILINGOVER = 0xf << 20,
LINK_SYNCHING = 0xc << 24
};
static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
struct sk_buff_head *xmitq);
static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
bool probe_reply, u16 rcvgap,
int tolerance, int priority,
struct sk_buff_head *xmitq);
static void link_print(struct tipc_link *l, const char *str);
static int tipc_link_build_nack_msg(struct tipc_link *l,
struct sk_buff_head *xmitq);
static void tipc_link_build_bc_init_msg(struct tipc_link *l,
struct sk_buff_head *xmitq);
static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
struct tipc_link *l, u8 start_index);
static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr);
static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
u16 acked, u16 gap,
struct tipc_gap_ack_blks *ga,
struct sk_buff_head *xmitq,
bool *retransmitted, int *rc);
static void tipc_link_update_cwin(struct tipc_link *l, int released,
bool retransmitted);
/*
* Simple non-static link routines (i.e. referenced outside this file)
*/
bool tipc_link_is_up(struct tipc_link *l)
{
return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
}
bool tipc_link_peer_is_down(struct tipc_link *l)
{
return l->state == LINK_PEER_RESET;
}
bool tipc_link_is_reset(struct tipc_link *l)
{
return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
}
bool tipc_link_is_establishing(struct tipc_link *l)
{
return l->state == LINK_ESTABLISHING;
}
bool tipc_link_is_synching(struct tipc_link *l)
{
return l->state == LINK_SYNCHING;
}
bool tipc_link_is_failingover(struct tipc_link *l)
{
return l->state == LINK_FAILINGOVER;
}
bool tipc_link_is_blocked(struct tipc_link *l)
{
return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
}
static bool link_is_bc_sndlink(struct tipc_link *l)
{
return !l->bc_sndlink;
}
static bool link_is_bc_rcvlink(struct tipc_link *l)
{
return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
}
void tipc_link_set_active(struct tipc_link *l, bool active)
{
l->active = active;
}
u32 tipc_link_id(struct tipc_link *l)
{
return l->peer_bearer_id << 16 | l->bearer_id;
}
int tipc_link_min_win(struct tipc_link *l)
{
return l->min_win;
}
int tipc_link_max_win(struct tipc_link *l)
{
return l->max_win;
}
int tipc_link_prio(struct tipc_link *l)
{
return l->priority;
}
unsigned long tipc_link_tolerance(struct tipc_link *l)
{
return l->tolerance;
}
struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
{
return l->inputq;
}
char tipc_link_plane(struct tipc_link *l)
{
return l->net_plane;
}
struct net *tipc_link_net(struct tipc_link *l)
{
return l->net;
}
void tipc_link_update_caps(struct tipc_link *l, u16 capabilities)
{
l->peer_caps = capabilities;
}
void tipc_link_add_bc_peer(struct tipc_link *snd_l,
struct tipc_link *uc_l,
struct sk_buff_head *xmitq)
{
struct tipc_link *rcv_l = uc_l->bc_rcvlink;
snd_l->ackers++;
rcv_l->acked = snd_l->snd_nxt - 1;
snd_l->state = LINK_ESTABLISHED;
tipc_link_build_bc_init_msg(uc_l, xmitq);
}
void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
struct tipc_link *rcv_l,
struct sk_buff_head *xmitq)
{
u16 ack = snd_l->snd_nxt - 1;
snd_l->ackers--;
rcv_l->bc_peer_is_up = true;
rcv_l->state = LINK_ESTABLISHED;
tipc_link_bc_ack_rcv(rcv_l, ack, 0, NULL, xmitq, NULL);
trace_tipc_link_reset(rcv_l, TIPC_DUMP_ALL, "bclink removed!");
tipc_link_reset(rcv_l);
rcv_l->state = LINK_RESET;
if (!snd_l->ackers) {
trace_tipc_link_reset(snd_l, TIPC_DUMP_ALL, "zero ackers!");
tipc_link_reset(snd_l);
snd_l->state = LINK_RESET;
__skb_queue_purge(xmitq);
}
}
int tipc_link_bc_peers(struct tipc_link *l)
{
return l->ackers;
}
static u16 link_bc_rcv_gap(struct tipc_link *l)
{
struct sk_buff *skb = skb_peek(&l->deferdq);
u16 gap = 0;
if (more(l->snd_nxt, l->rcv_nxt))
gap = l->snd_nxt - l->rcv_nxt;
if (skb)
gap = buf_seqno(skb) - l->rcv_nxt;
return gap;
}
void tipc_link_set_mtu(struct tipc_link *l, int mtu)
{
l->mtu = mtu;
}
int tipc_link_mtu(struct tipc_link *l)
{
return l->mtu;
}
int tipc_link_mss(struct tipc_link *l)
{
#ifdef CONFIG_TIPC_CRYPTO
return l->mtu - INT_H_SIZE - EMSG_OVERHEAD;
#else
return l->mtu - INT_H_SIZE;
#endif
}
u16 tipc_link_rcv_nxt(struct tipc_link *l)
{
return l->rcv_nxt;
}
u16 tipc_link_acked(struct tipc_link *l)
{
return l->acked;
}
char *tipc_link_name(struct tipc_link *l)
{
return l->name;
}
u32 tipc_link_state(struct tipc_link *l)
{
return l->state;
}
/**
* tipc_link_create - create a new link
* @net: pointer to associated network namespace
* @if_name: associated interface name
* @bearer_id: id (index) of associated bearer
* @tolerance: link tolerance to be used by link
* @net_plane: network plane (A,B,c..) this link belongs to
* @mtu: mtu to be advertised by link
* @priority: priority to be used by link
* @min_win: minimal send window to be used by link
* @max_win: maximal send window to be used by link
* @session: session to be used by link
* @peer: node id of peer node
* @peer_caps: bitmap describing peer node capabilities
* @bc_sndlink: the namespace global link used for broadcast sending
* @bc_rcvlink: the peer specific link used for broadcast reception
* @inputq: queue to put messages ready for delivery
* @namedq: queue to put binding table update messages ready for delivery
* @link: return value, pointer to put the created link
* @self: local unicast link id
* @peer_id: 128-bit ID of peer
*
* Return: true if link was created, otherwise false
*/
bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
int tolerance, char net_plane, u32 mtu, int priority,
u32 min_win, u32 max_win, u32 session, u32 self,
u32 peer, u8 *peer_id, u16 peer_caps,
struct tipc_link *bc_sndlink,
struct tipc_link *bc_rcvlink,
struct sk_buff_head *inputq,
struct sk_buff_head *namedq,
struct tipc_link **link)
{
char peer_str[NODE_ID_STR_LEN] = {0,};
char self_str[NODE_ID_STR_LEN] = {0,};
struct tipc_link *l;
l = kzalloc(sizeof(*l), GFP_ATOMIC);
if (!l)
return false;
*link = l;
l->session = session;
/* Set link name for unicast links only */
if (peer_id) {
tipc_nodeid2string(self_str, tipc_own_id(net));
if (strlen(self_str) > 16)
sprintf(self_str, "%x", self);
tipc_nodeid2string(peer_str, peer_id);
if (strlen(peer_str) > 16)
sprintf(peer_str, "%x", peer);
}
/* Peer i/f name will be completed by reset/activate message */
snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown",
self_str, if_name, peer_str);
strcpy(l->if_name, if_name);
l->addr = peer;
l->peer_caps = peer_caps;
l->net = net;
l->in_session = false;
l->bearer_id = bearer_id;
l->tolerance = tolerance;
if (bc_rcvlink)
bc_rcvlink->tolerance = tolerance;
l->net_plane = net_plane;
l->advertised_mtu = mtu;
l->mtu = mtu;
l->priority = priority;
tipc_link_set_queue_limits(l, min_win, max_win);
l->ackers = 1;
l->bc_sndlink = bc_sndlink;
l->bc_rcvlink = bc_rcvlink;
l->inputq = inputq;
l->namedq = namedq;
l->state = LINK_RESETTING;
__skb_queue_head_init(&l->transmq);
__skb_queue_head_init(&l->backlogq);
__skb_queue_head_init(&l->deferdq);
__skb_queue_head_init(&l->failover_deferdq);
skb_queue_head_init(&l->wakeupq);
skb_queue_head_init(l->inputq);
return true;
}
/**
* tipc_link_bc_create - create new link to be used for broadcast
* @net: pointer to associated network namespace
* @mtu: mtu to be used initially if no peers
* @min_win: minimal send window to be used by link
* @max_win: maximal send window to be used by link
* @inputq: queue to put messages ready for delivery
* @namedq: queue to put binding table update messages ready for delivery
* @link: return value, pointer to put the created link
* @ownnode: identity of own node
* @peer: node id of peer node
* @peer_id: 128-bit ID of peer
* @peer_caps: bitmap describing peer node capabilities
* @bc_sndlink: the namespace global link used for broadcast sending
*
* Return: true if link was created, otherwise false
*/
bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer, u8 *peer_id,
int mtu, u32 min_win, u32 max_win, u16 peer_caps,
struct sk_buff_head *inputq,
struct sk_buff_head *namedq,
struct tipc_link *bc_sndlink,
struct tipc_link **link)
{
struct tipc_link *l;
if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, min_win,
max_win, 0, ownnode, peer, NULL, peer_caps,
bc_sndlink, NULL, inputq, namedq, link))
return false;
l = *link;
if (peer_id) {
char peer_str[NODE_ID_STR_LEN] = {0,};
tipc_nodeid2string(peer_str, peer_id);
if (strlen(peer_str) > 16)
sprintf(peer_str, "%x", peer);
/* Broadcast receiver link name: "broadcast-link:<peer>" */
snprintf(l->name, sizeof(l->name), "%s:%s", tipc_bclink_name,
peer_str);
} else {
strcpy(l->name, tipc_bclink_name);
}
trace_tipc_link_reset(l, TIPC_DUMP_ALL, "bclink created!");
tipc_link_reset(l);
l->state = LINK_RESET;
l->ackers = 0;
l->bc_rcvlink = l;
/* Broadcast send link is always up */
if (link_is_bc_sndlink(l))
l->state = LINK_ESTABLISHED;
/* Disable replicast if even a single peer doesn't support it */
if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST))
tipc_bcast_toggle_rcast(net, false);
return true;
}
/**
* tipc_link_fsm_evt - link finite state machine
* @l: pointer to link
* @evt: state machine event to be processed
*/
int tipc_link_fsm_evt(struct tipc_link *l, int evt)
{
int rc = 0;
int old_state = l->state;
switch (l->state) {
case LINK_RESETTING:
switch (evt) {
case LINK_PEER_RESET_EVT:
l->state = LINK_PEER_RESET;
break;
case LINK_RESET_EVT:
l->state = LINK_RESET;
break;
case LINK_FAILURE_EVT:
case LINK_FAILOVER_BEGIN_EVT:
case LINK_ESTABLISH_EVT:
case LINK_FAILOVER_END_EVT:
case LINK_SYNCH_BEGIN_EVT:
case LINK_SYNCH_END_EVT:
default:
goto illegal_evt;
}
break;
case LINK_RESET:
switch (evt) {
case LINK_PEER_RESET_EVT:
l->state = LINK_ESTABLISHING;
break;
case LINK_FAILOVER_BEGIN_EVT:
l->state = LINK_FAILINGOVER;
break;
case LINK_FAILURE_EVT:
case LINK_RESET_EVT:
case LINK_ESTABLISH_EVT:
case LINK_FAILOVER_END_EVT:
break;
case LINK_SYNCH_BEGIN_EVT:
case LINK_SYNCH_END_EVT:
default:
goto illegal_evt;
}
break;
case LINK_PEER_RESET:
switch (evt) {
case LINK_RESET_EVT:
l->state = LINK_ESTABLISHING;
break;
case LINK_PEER_RESET_EVT:
case LINK_ESTABLISH_EVT:
case LINK_FAILURE_EVT:
break;
case LINK_SYNCH_BEGIN_EVT:
case LINK_SYNCH_END_EVT:
case LINK_FAILOVER_BEGIN_EVT:
case LINK_FAILOVER_END_EVT:
default:
goto illegal_evt;
}
break;
case LINK_FAILINGOVER:
switch (evt) {
case LINK_FAILOVER_END_EVT:
l->state = LINK_RESET;
break;
case LINK_PEER_RESET_EVT:
case LINK_RESET_EVT:
case LINK_ESTABLISH_EVT:
case LINK_FAILURE_EVT:
break;
case LINK_FAILOVER_BEGIN_EVT:
case LINK_SYNCH_BEGIN_EVT:
case LINK_SYNCH_END_EVT:
default:
goto illegal_evt;
}
break;
case LINK_ESTABLISHING:
switch (evt) {
case LINK_ESTABLISH_EVT:
l->state = LINK_ESTABLISHED;
break;
case LINK_FAILOVER_BEGIN_EVT:
l->state = LINK_FAILINGOVER;
break;
case LINK_RESET_EVT:
l->state = LINK_RESET;
break;
case LINK_FAILURE_EVT:
case LINK_PEER_RESET_EVT:
case LINK_SYNCH_BEGIN_EVT:
case LINK_FAILOVER_END_EVT:
break;
case LINK_SYNCH_END_EVT:
default:
goto illegal_evt;
}
break;
case LINK_ESTABLISHED:
switch (evt) {
case LINK_PEER_RESET_EVT:
l->state = LINK_PEER_RESET;
rc |= TIPC_LINK_DOWN_EVT;
break;
case LINK_FAILURE_EVT:
l->state = LINK_RESETTING;
rc |= TIPC_LINK_DOWN_EVT;
break;
case LINK_RESET_EVT:
l->state = LINK_RESET;
break;
case LINK_ESTABLISH_EVT:
case LINK_SYNCH_END_EVT:
break;
case LINK_SYNCH_BEGIN_EVT:
l->state = LINK_SYNCHING;
break;
case LINK_FAILOVER_BEGIN_EVT:
case LINK_FAILOVER_END_EVT:
default:
goto illegal_evt;
}
break;
case LINK_SYNCHING:
switch (evt) {
case LINK_PEER_RESET_EVT:
l->state = LINK_PEER_RESET;
rc |= TIPC_LINK_DOWN_EVT;
break;
case LINK_FAILURE_EVT:
l->state = LINK_RESETTING;
rc |= TIPC_LINK_DOWN_EVT;
break;
case LINK_RESET_EVT:
l->state = LINK_RESET;
break;
case LINK_ESTABLISH_EVT:
case LINK_SYNCH_BEGIN_EVT:
break;
case LINK_SYNCH_END_EVT:
l->state = LINK_ESTABLISHED;
break;
case LINK_FAILOVER_BEGIN_EVT:
case LINK_FAILOVER_END_EVT:
default:
goto illegal_evt;
}
break;
default:
pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
}
trace_tipc_link_fsm(l->name, old_state, l->state, evt);
return rc;
illegal_evt:
pr_err("Illegal FSM event %x in state %x on link %s\n",
evt, l->state, l->name);
trace_tipc_link_fsm(l->name, old_state, l->state, evt);
return rc;
}
/* link_profile_stats - update statistical profiling of traffic
*/
static void link_profile_stats(struct tipc_link *l)
{
struct sk_buff *skb;
struct tipc_msg *msg;
int length;
/* Update counters used in statistical profiling of send traffic */
l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
l->stats.queue_sz_counts++;
skb = skb_peek(&l->transmq);
if (!skb)
return;
msg = buf_msg(skb);
length = msg_size(msg);
if (msg_user(msg) == MSG_FRAGMENTER) {
if (msg_type(msg) != FIRST_FRAGMENT)
return;
length = msg_size(msg_inner_hdr(msg));
}
l->stats.msg_lengths_total += length;
l->stats.msg_length_counts++;
if (length <= 64)
l->stats.msg_length_profile[0]++;
else if (length <= 256)
l->stats.msg_length_profile[1]++;
else if (length <= 1024)
l->stats.msg_length_profile[2]++;
else if (length <= 4096)
l->stats.msg_length_profile[3]++;
else if (length <= 16384)
l->stats.msg_length_profile[4]++;
else if (length <= 32768)
l->stats.msg_length_profile[5]++;
else
l->stats.msg_length_profile[6]++;
}
/**
* tipc_link_too_silent - check if link is "too silent"
* @l: tipc link to be checked
*
* Return: true if the link 'silent_intv_cnt' is about to reach the
* 'abort_limit' value, otherwise false
*/
bool tipc_link_too_silent(struct tipc_link *l)
{
return (l->silent_intv_cnt + 2 > l->abort_limit);
}
/* tipc_link_timeout - perform periodic task as instructed from node timeout
*/
int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
{
int mtyp = 0;
int rc = 0;
bool state = false;
bool probe = false;
bool setup = false;
u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
u16 bc_acked = l->bc_rcvlink->acked;
struct tipc_mon_state *mstate = &l->mon_state;
trace_tipc_link_timeout(l, TIPC_DUMP_NONE, " ");
trace_tipc_link_too_silent(l, TIPC_DUMP_ALL, " ");
switch (l->state) {
case LINK_ESTABLISHED:
case LINK_SYNCHING:
mtyp = STATE_MSG;
link_profile_stats(l);
tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
state = bc_acked != bc_snt;
state |= l->bc_rcvlink->rcv_unacked;
state |= l->rcv_unacked;
state |= !skb_queue_empty(&l->transmq);
probe = mstate->probing;
probe |= l->silent_intv_cnt;
if (probe || mstate->monitoring)
l->silent_intv_cnt++;
probe |= !skb_queue_empty(&l->deferdq);
if (l->snd_nxt == l->checkpoint) {
tipc_link_update_cwin(l, 0, 0);
probe = true;
}
l->checkpoint = l->snd_nxt;
break;
case LINK_RESET:
setup = l->rst_cnt++ <= 4;
setup |= !(l->rst_cnt % 16);
mtyp = RESET_MSG;
break;
case LINK_ESTABLISHING:
setup = true;
mtyp = ACTIVATE_MSG;
break;
case LINK_PEER_RESET:
case LINK_RESETTING:
case LINK_FAILINGOVER:
break;
default:
break;
}
if (state || probe || setup)
tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq);
return rc;
}
/**
* link_schedule_user - schedule a message sender for wakeup after congestion
* @l: congested link
* @hdr: header of message that is being sent
* Create pseudo msg to send back to user when congestion abates
*/
static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr)
{
u32 dnode = tipc_own_addr(l->net);
u32 dport = msg_origport(hdr);
struct sk_buff *skb;
/* Create and schedule wakeup pseudo message */
skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
dnode, l->addr, dport, 0, 0);
if (!skb)
return -ENOBUFS;
msg_set_dest_droppable(buf_msg(skb), true);
TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr);
skb_queue_tail(&l->wakeupq, skb);
l->stats.link_congs++;
trace_tipc_link_conges(l, TIPC_DUMP_ALL, "wakeup scheduled!");
return -ELINKCONG;
}
/**
* link_prepare_wakeup - prepare users for wakeup after congestion
* @l: congested link
* Wake up a number of waiting users, as permitted by available space
* in the send queue
*/
static void link_prepare_wakeup(struct tipc_link *l)
{
struct sk_buff_head *wakeupq = &l->wakeupq;
struct sk_buff_head *inputq = l->inputq;
struct sk_buff *skb, *tmp;
struct sk_buff_head tmpq;
int avail[5] = {0,};
int imp = 0;
__skb_queue_head_init(&tmpq);
for (; imp <= TIPC_SYSTEM_IMPORTANCE; imp++)
avail[imp] = l->backlog[imp].limit - l->backlog[imp].len;
skb_queue_walk_safe(wakeupq, skb, tmp) {
imp = TIPC_SKB_CB(skb)->chain_imp;
if (avail[imp] <= 0)
continue;
avail[imp]--;
__skb_unlink(skb, wakeupq);
__skb_queue_tail(&tmpq, skb);
}
spin_lock_bh(&inputq->lock);
skb_queue_splice_tail(&tmpq, inputq);
spin_unlock_bh(&inputq->lock);
}
/**
* tipc_link_set_skb_retransmit_time - set the time at which retransmission of
* the given skb should be next attempted
* @skb: skb to set a future retransmission time for
* @l: link the skb will be transmitted on
*/
static void tipc_link_set_skb_retransmit_time(struct sk_buff *skb,
struct tipc_link *l)
{
if (link_is_bc_sndlink(l))
TIPC_SKB_CB(skb)->nxt_retr = TIPC_BC_RETR_LIM;
else
TIPC_SKB_CB(skb)->nxt_retr = TIPC_UC_RETR_TIME;
}
void tipc_link_reset(struct tipc_link *l)
{
struct sk_buff_head list;
u32 imp;
__skb_queue_head_init(&list);
l->in_session = false;
/* Force re-synch of peer session number before establishing */
l->peer_session--;
l->session++;
l->mtu = l->advertised_mtu;
spin_lock_bh(&l->wakeupq.lock);
skb_queue_splice_init(&l->wakeupq, &list);
spin_unlock_bh(&l->wakeupq.lock);
spin_lock_bh(&l->inputq->lock);
skb_queue_splice_init(&list, l->inputq);
spin_unlock_bh(&l->inputq->lock);
__skb_queue_purge(&l->transmq);
__skb_queue_purge(&l->deferdq);
__skb_queue_purge(&l->backlogq);
__skb_queue_purge(&l->failover_deferdq);
for (imp = 0; imp <= TIPC_SYSTEM_IMPORTANCE; imp++) {
l->backlog[imp].len = 0;
l->backlog[imp].target_bskb = NULL;
}
kfree_skb(l->reasm_buf);
kfree_skb(l->reasm_tnlmsg);
kfree_skb(l->failover_reasm_skb);
l->reasm_buf = NULL;
l->reasm_tnlmsg = NULL;
l->failover_reasm_skb = NULL;
l->rcv_unacked = 0;
l->snd_nxt = 1;
l->rcv_nxt = 1;
l->snd_nxt_state = 1;
l->rcv_nxt_state = 1;
l->acked = 0;
l->last_gap = 0;
kfree(l->last_ga);
l->last_ga = NULL;
l->silent_intv_cnt = 0;
l->rst_cnt = 0;
l->bc_peer_is_up = false;
memset(&l->mon_state, 0, sizeof(l->mon_state));
tipc_link_reset_stats(l);
}
/**
* tipc_link_xmit(): enqueue buffer list according to queue situation
* @l: link to use
* @list: chain of buffers containing message
* @xmitq: returned list of packets to be sent by caller
*
* Consumes the buffer chain.
* Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
* Return: 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
*/
int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
struct sk_buff_head *xmitq)
{
struct sk_buff_head *backlogq = &l->backlogq;
struct sk_buff_head *transmq = &l->transmq;
struct sk_buff *skb, *_skb;
u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
u16 ack = l->rcv_nxt - 1;
u16 seqno = l->snd_nxt;
int pkt_cnt = skb_queue_len(list);
unsigned int mss = tipc_link_mss(l);
unsigned int cwin = l->window;
unsigned int mtu = l->mtu;
struct tipc_msg *hdr;
bool new_bundle;
int rc = 0;
int imp;
if (pkt_cnt <= 0)
return 0;
hdr = buf_msg(skb_peek(list));
if (unlikely(msg_size(hdr) > mtu)) {
pr_warn("Too large msg, purging xmit list %d %d %d %d %d!\n",
skb_queue_len(list), msg_user(hdr),
msg_type(hdr), msg_size(hdr), mtu);
__skb_queue_purge(list);
return -EMSGSIZE;
}
imp = msg_importance(hdr);
/* Allow oversubscription of one data msg per source at congestion */
if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) {
if (imp == TIPC_SYSTEM_IMPORTANCE) {
pr_warn("%s<%s>, link overflow", link_rst_msg, l->name);
return -ENOBUFS;
}
rc = link_schedule_user(l, hdr);
}
if (pkt_cnt > 1) {
l->stats.sent_fragmented++;
l->stats.sent_fragments += pkt_cnt;
}
/* Prepare each packet for sending, and add to relevant queue: */
while ((skb = __skb_dequeue(list))) {
if (likely(skb_queue_len(transmq) < cwin)) {
hdr = buf_msg(skb);
msg_set_seqno(hdr, seqno);
msg_set_ack(hdr, ack);
msg_set_bcast_ack(hdr, bc_ack);
_skb = skb_clone(skb, GFP_ATOMIC);
if (!_skb) {
kfree_skb(skb);
__skb_queue_purge(list);
return -ENOBUFS;
}
__skb_queue_tail(transmq, skb);
tipc_link_set_skb_retransmit_time(skb, l);
__skb_queue_tail(xmitq, _skb);
TIPC_SKB_CB(skb)->ackers = l->ackers;
l->rcv_unacked = 0;
l->stats.sent_pkts++;
seqno++;
continue;
}
if (tipc_msg_try_bundle(l->backlog[imp].target_bskb, &skb,
mss, l->addr, &new_bundle)) {
if (skb) {
/* Keep a ref. to the skb for next try */
l->backlog[imp].target_bskb = skb;
l->backlog[imp].len++;
__skb_queue_tail(backlogq, skb);
} else {
if (new_bundle) {
l->stats.sent_bundles++;
l->stats.sent_bundled++;
}
l->stats.sent_bundled++;
}
continue;
}
l->backlog[imp].target_bskb = NULL;
l->backlog[imp].len += (1 + skb_queue_len(list));
__skb_queue_tail(backlogq, skb);
skb_queue_splice_tail_init(list, backlogq);
}
l->snd_nxt = seqno;
return rc;
}
static void tipc_link_update_cwin(struct tipc_link *l, int released,
bool retransmitted)
{
int bklog_len = skb_queue_len(&l->backlogq);
struct sk_buff_head *txq = &l->transmq;
int txq_len = skb_queue_len(txq);
u16 cwin = l->window;
/* Enter fast recovery */
if (unlikely(retransmitted)) {
l->ssthresh = max_t(u16, l->window / 2, 300);
l->window = min_t(u16, l->ssthresh, l->window);
return;
}
/* Enter slow start */
if (unlikely(!released)) {
l->ssthresh = max_t(u16, l->window / 2, 300);
l->window = l->min_win;
return;
}
/* Don't increase window if no pressure on the transmit queue */
if (txq_len + bklog_len < cwin)
return;
/* Don't increase window if there are holes the transmit queue */
if (txq_len && l->snd_nxt - buf_seqno(skb_peek(txq)) != txq_len)
return;
l->cong_acks += released;
/* Slow start */
if (cwin <= l->ssthresh) {
l->window = min_t(u16, cwin + released, l->max_win);
return;
}
/* Congestion avoidance */
if (l->cong_acks < cwin)
return;
l->window = min_t(u16, ++cwin, l->max_win);
l->cong_acks = 0;
}
static void tipc_link_advance_backlog(struct tipc_link *l,
struct sk_buff_head *xmitq)
{
u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
struct sk_buff_head *txq = &l->transmq;
struct sk_buff *skb, *_skb;
u16 ack = l->rcv_nxt - 1;
u16 seqno = l->snd_nxt;
struct tipc_msg *hdr;
u16 cwin = l->window;
u32 imp;
while (skb_queue_len(txq) < cwin) {
skb = skb_peek(&l->backlogq);
if (!skb)
break;
_skb = skb_clone(skb, GFP_ATOMIC);
if (!_skb)
break;
__skb_dequeue(&l->backlogq);
hdr = buf_msg(skb);
imp = msg_importance(hdr);
l->backlog[imp].len--;
if (unlikely(skb == l->backlog[imp].target_bskb))
l->backlog[imp].target_bskb = NULL;
__skb_queue_tail(&l->transmq, skb);
tipc_link_set_skb_retransmit_time(skb, l);
__skb_queue_tail(xmitq, _skb);
TIPC_SKB_CB(skb)->ackers = l->ackers;
msg_set_seqno(hdr, seqno);
msg_set_ack(hdr, ack);
msg_set_bcast_ack(hdr, bc_ack);
l->rcv_unacked = 0;
l->stats.sent_pkts++;
seqno++;
}
l->snd_nxt = seqno;
}
/**
* link_retransmit_failure() - Detect repeated retransmit failures
* @l: tipc link sender
* @r: tipc link receiver (= l in case of unicast)
* @rc: returned code
*
* Return: true if the repeated retransmit failures happens, otherwise
* false
*/
static bool link_retransmit_failure(struct tipc_link *l, struct tipc_link *r,
int *rc)
{
struct sk_buff *skb = skb_peek(&l->transmq);
struct tipc_msg *hdr;
if (!skb)
return false;
if (!TIPC_SKB_CB(skb)->retr_cnt)
return false;
if (!time_after(jiffies, TIPC_SKB_CB(skb)->retr_stamp +
msecs_to_jiffies(r->tolerance * 10)))
return false;
hdr = buf_msg(skb);
if (link_is_bc_sndlink(l) && !less(r->acked, msg_seqno(hdr)))
return false;
pr_warn("Retransmission failure on link <%s>\n", l->name);
link_print(l, "State of link ");
pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
pr_info("sqno %u, prev: %x, dest: %x\n",
msg_seqno(hdr), msg_prevnode(hdr), msg_destnode(hdr));
pr_info("retr_stamp %d, retr_cnt %d\n",
jiffies_to_msecs(TIPC_SKB_CB(skb)->retr_stamp),
TIPC_SKB_CB(skb)->retr_cnt);
trace_tipc_list_dump(&l->transmq, true, "retrans failure!");
trace_tipc_link_dump(l, TIPC_DUMP_NONE, "retrans failure!");
trace_tipc_link_dump(r, TIPC_DUMP_NONE, "retrans failure!");
if (link_is_bc_sndlink(l)) {
r->state = LINK_RESET;
*rc |= TIPC_LINK_DOWN_EVT;
} else {
*rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
}
return true;
}
/* tipc_data_input - deliver data and name distr msgs to upper layer
*
* Consumes buffer if message is of right type
* Node lock must be held
*/
static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
struct sk_buff_head *inputq)
{
struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq;
struct tipc_msg *hdr = buf_msg(skb);
switch (msg_user(hdr)) {
case TIPC_LOW_IMPORTANCE:
case TIPC_MEDIUM_IMPORTANCE:
case TIPC_HIGH_IMPORTANCE:
case TIPC_CRITICAL_IMPORTANCE:
if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) {
skb_queue_tail(mc_inputq, skb);
return true;
}
fallthrough;
case CONN_MANAGER:
skb_queue_tail(inputq, skb);
return true;
case GROUP_PROTOCOL:
skb_queue_tail(mc_inputq, skb);
return true;
case NAME_DISTRIBUTOR:
l->bc_rcvlink->state = LINK_ESTABLISHED;
skb_queue_tail(l->namedq, skb);
return true;
case MSG_BUNDLER:
case TUNNEL_PROTOCOL:
case MSG_FRAGMENTER:
case BCAST_PROTOCOL:
return false;
#ifdef CONFIG_TIPC_CRYPTO
case MSG_CRYPTO:
if (sysctl_tipc_key_exchange_enabled &&
TIPC_SKB_CB(skb)->decrypted) {
tipc_crypto_msg_rcv(l->net, skb);
return true;
}
fallthrough;
#endif
default:
pr_warn("Dropping received illegal msg type\n");
kfree_skb(skb);
return true;
}
}
/* tipc_link_input - process packet that has passed link protocol check
*
* Consumes buffer
*/
static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
struct sk_buff_head *inputq,
struct sk_buff **reasm_skb)
{
struct tipc_msg *hdr = buf_msg(skb);
struct sk_buff *iskb;
struct sk_buff_head tmpq;
int usr = msg_user(hdr);
int pos = 0;
if (usr == MSG_BUNDLER) {
skb_queue_head_init(&tmpq);
l->stats.recv_bundles++;
l->stats.recv_bundled += msg_msgcnt(hdr);
while (tipc_msg_extract(skb, &iskb, &pos))
tipc_data_input(l, iskb, &tmpq);
tipc_skb_queue_splice_tail(&tmpq, inputq);
return 0;
} else if (usr == MSG_FRAGMENTER) {
l->stats.recv_fragments++;
if (tipc_buf_append(reasm_skb, &skb)) {
l->stats.recv_fragmented++;
tipc_data_input(l, skb, inputq);
} else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
pr_warn_ratelimited("Unable to build fragment list\n");
return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
}
return 0;
} else if (usr == BCAST_PROTOCOL) {
tipc_bcast_lock(l->net);
tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
tipc_bcast_unlock(l->net);
}
kfree_skb(skb);
return 0;
}
/* tipc_link_tnl_rcv() - receive TUNNEL_PROTOCOL message, drop or process the
* inner message along with the ones in the old link's
* deferdq
* @l: tunnel link
* @skb: TUNNEL_PROTOCOL message
* @inputq: queue to put messages ready for delivery
*/
static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb,
struct sk_buff_head *inputq)
{
struct sk_buff **reasm_skb = &l->failover_reasm_skb;
struct sk_buff **reasm_tnlmsg = &l->reasm_tnlmsg;
struct sk_buff_head *fdefq = &l->failover_deferdq;
struct tipc_msg *hdr = buf_msg(skb);
struct sk_buff *iskb;
int ipos = 0;
int rc = 0;
u16 seqno;
if (msg_type(hdr) == SYNCH_MSG) {
kfree_skb(skb);
return 0;
}
/* Not a fragment? */
if (likely(!msg_nof_fragms(hdr))) {
if (unlikely(!tipc_msg_extract(skb, &iskb, &ipos))) {
pr_warn_ratelimited("Unable to extract msg, defq: %d\n",
skb_queue_len(fdefq));
return 0;
}
kfree_skb(skb);
} else {
/* Set fragment type for buf_append */
if (msg_fragm_no(hdr) == 1)
msg_set_type(hdr, FIRST_FRAGMENT);
else if (msg_fragm_no(hdr) < msg_nof_fragms(hdr))
msg_set_type(hdr, FRAGMENT);
else
msg_set_type(hdr, LAST_FRAGMENT);
if (!tipc_buf_append(reasm_tnlmsg, &skb)) {
/* Successful but non-complete reassembly? */
if (*reasm_tnlmsg || link_is_bc_rcvlink(l))
return 0;
pr_warn_ratelimited("Unable to reassemble tunnel msg\n");
return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
}
iskb = skb;
}
do {
seqno = buf_seqno(iskb);
if (unlikely(less(seqno, l->drop_point))) {
kfree_skb(iskb);
continue;
}
if (unlikely(seqno != l->drop_point)) {
__tipc_skb_queue_sorted(fdefq, seqno, iskb);
continue;
}
l->drop_point++;
if (!tipc_data_input(l, iskb, inputq))
rc |= tipc_link_input(l, iskb, inputq, reasm_skb);
if (unlikely(rc))
break;
} while ((iskb = __tipc_skb_dequeue(fdefq, l->drop_point)));
return rc;
}
/**
* tipc_get_gap_ack_blks - get Gap ACK blocks from PROTOCOL/STATE_MSG
* @ga: returned pointer to the Gap ACK blocks if any
* @l: the tipc link
* @hdr: the PROTOCOL/STATE_MSG header
* @uc: desired Gap ACK blocks type, i.e. unicast (= 1) or broadcast (= 0)
*
* Return: the total Gap ACK blocks size
*/
u16 tipc_get_gap_ack_blks(struct tipc_gap_ack_blks **ga, struct tipc_link *l,
struct tipc_msg *hdr, bool uc)
{
struct tipc_gap_ack_blks *p;
u16 sz = 0;
/* Does peer support the Gap ACK blocks feature? */
if (l->peer_caps & TIPC_GAP_ACK_BLOCK) {
p = (struct tipc_gap_ack_blks *)msg_data(hdr);
sz = ntohs(p->len);
/* Sanity check */
if (sz == struct_size(p, gacks, size_add(p->ugack_cnt, p->bgack_cnt))) {
/* Good, check if the desired type exists */
if ((uc && p->ugack_cnt) || (!uc && p->bgack_cnt))
goto ok;
/* Backward compatible: peer might not support bc, but uc? */
} else if (uc && sz == struct_size(p, gacks, p->ugack_cnt)) {
if (p->ugack_cnt) {
p->bgack_cnt = 0;
goto ok;
}
}
}
/* Other cases: ignore! */
p = NULL;
ok:
*ga = p;
return sz;
}
static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
struct tipc_link *l, u8 start_index)
{
struct tipc_gap_ack *gacks = &ga->gacks[start_index];
struct sk_buff *skb = skb_peek(&l->deferdq);
u16 expect, seqno = 0;
u8 n = 0;
if (!skb)
return 0;
expect = buf_seqno(skb);
skb_queue_walk(&l->deferdq, skb) {
seqno = buf_seqno(skb);
if (unlikely(more(seqno, expect))) {
gacks[n].ack = htons(expect - 1);
gacks[n].gap = htons(seqno - expect);
if (++n >= MAX_GAP_ACK_BLKS / 2) {
pr_info_ratelimited("Gacks on %s: %d, ql: %d!\n",
l->name, n,
skb_queue_len(&l->deferdq));
return n;
}
} else if (unlikely(less(seqno, expect))) {
pr_warn("Unexpected skb in deferdq!\n");
continue;
}
expect = seqno + 1;
}
/* last block */
gacks[n].ack = htons(seqno);
gacks[n].gap = 0;
n++;
return n;
}
/* tipc_build_gap_ack_blks - build Gap ACK blocks
* @l: tipc unicast link
* @hdr: the tipc message buffer to store the Gap ACK blocks after built
*
* The function builds Gap ACK blocks for both the unicast & broadcast receiver
* links of a certain peer, the buffer after built has the network data format
* as found at the struct tipc_gap_ack_blks definition.
*
* returns the actual allocated memory size
*/
static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr)
{
struct tipc_link *bcl = l->bc_rcvlink;
struct tipc_gap_ack_blks *ga;
u16 len;
ga = (struct tipc_gap_ack_blks *)msg_data(hdr);
/* Start with broadcast link first */
tipc_bcast_lock(bcl->net);
msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
ga->bgack_cnt = __tipc_build_gap_ack_blks(ga, bcl, 0);
tipc_bcast_unlock(bcl->net);
/* Now for unicast link, but an explicit NACK only (???) */
ga->ugack_cnt = (msg_seq_gap(hdr)) ?
__tipc_build_gap_ack_blks(ga, l, ga->bgack_cnt) : 0;
/* Total len */
len = struct_size(ga, gacks, size_add(ga->bgack_cnt, ga->ugack_cnt));
ga->len = htons(len);
return len;
}
/* tipc_link_advance_transmq - advance TIPC link transmq queue by releasing
* acked packets, also doing retransmissions if
* gaps found
* @l: tipc link with transmq queue to be advanced
* @r: tipc link "receiver" i.e. in case of broadcast (= "l" if unicast)
* @acked: seqno of last packet acked by peer without any gaps before
* @gap: # of gap packets
* @ga: buffer pointer to Gap ACK blocks from peer
* @xmitq: queue for accumulating the retransmitted packets if any
* @retransmitted: returned boolean value if a retransmission is really issued
* @rc: returned code e.g. TIPC_LINK_DOWN_EVT if a repeated retransmit failures
* happens (- unlikely case)
*
* Return: the number of packets released from the link transmq
*/
static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
u16 acked, u16 gap,
struct tipc_gap_ack_blks *ga,
struct sk_buff_head *xmitq,
bool *retransmitted, int *rc)
{
struct tipc_gap_ack_blks *last_ga = r->last_ga, *this_ga = NULL;
struct tipc_gap_ack *gacks = NULL;
struct sk_buff *skb, *_skb, *tmp;
struct tipc_msg *hdr;
u32 qlen = skb_queue_len(&l->transmq);
u16 nacked = acked, ngap = gap, gack_cnt = 0;
u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
u16 ack = l->rcv_nxt - 1;
u16 seqno, n = 0;
u16 end = r->acked, start = end, offset = r->last_gap;
u16 si = (last_ga) ? last_ga->start_index : 0;
bool is_uc = !link_is_bc_sndlink(l);
bool bc_has_acked = false;
trace_tipc_link_retrans(r, acked + 1, acked + gap, &l->transmq);
/* Determine Gap ACK blocks if any for the particular link */
if (ga && is_uc) {
/* Get the Gap ACKs, uc part */
gack_cnt = ga->ugack_cnt;
gacks = &ga->gacks[ga->bgack_cnt];
} else if (ga) {
/* Copy the Gap ACKs, bc part, for later renewal if needed */
this_ga = kmemdup(ga, struct_size(ga, gacks, ga->bgack_cnt),
GFP_ATOMIC);
if (likely(this_ga)) {
this_ga->start_index = 0;
/* Start with the bc Gap ACKs */
gack_cnt = this_ga->bgack_cnt;
gacks = &this_ga->gacks[0];
} else {
/* Hmm, we can get in trouble..., simply ignore it */
pr_warn_ratelimited("Ignoring bc Gap ACKs, no memory\n");
}
}
/* Advance the link transmq */
skb_queue_walk_safe(&l->transmq, skb, tmp) {
seqno = buf_seqno(skb);
next_gap_ack:
if (less_eq(seqno, nacked)) {
if (is_uc)
goto release;
/* Skip packets peer has already acked */
if (!more(seqno, r->acked))
continue;
/* Get the next of last Gap ACK blocks */
while (more(seqno, end)) {
if (!last_ga || si >= last_ga->bgack_cnt)
break;
start = end + offset + 1;
end = ntohs(last_ga->gacks[si].ack);
offset = ntohs(last_ga->gacks[si].gap);
si++;
WARN_ONCE(more(start, end) ||
(!offset &&
si < last_ga->bgack_cnt) ||
si > MAX_GAP_ACK_BLKS,
"Corrupted Gap ACK: %d %d %d %d %d\n",
start, end, offset, si,
last_ga->bgack_cnt);
}
/* Check against the last Gap ACK block */
if (tipc_in_range(seqno, start, end))
continue;
/* Update/release the packet peer is acking */
bc_has_acked = true;
if (--TIPC_SKB_CB(skb)->ackers)
continue;
release:
/* release skb */
__skb_unlink(skb, &l->transmq);
kfree_skb(skb);
} else if (less_eq(seqno, nacked + ngap)) {
/* First gap: check if repeated retrans failures? */
if (unlikely(seqno == acked + 1 &&
link_retransmit_failure(l, r, rc))) {
/* Ignore this bc Gap ACKs if any */
kfree(this_ga);
this_ga = NULL;
break;
}
/* retransmit skb if unrestricted*/
if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr))
continue;
tipc_link_set_skb_retransmit_time(skb, l);
_skb = pskb_copy(skb, GFP_ATOMIC);
if (!_skb)
continue;
hdr = buf_msg(_skb);
msg_set_ack(hdr, ack);
msg_set_bcast_ack(hdr, bc_ack);
_skb->priority = TC_PRIO_CONTROL;
__skb_queue_tail(xmitq, _skb);
l->stats.retransmitted++;
if (!is_uc)
r->stats.retransmitted++;
*retransmitted = true;
/* Increase actual retrans counter & mark first time */
if (!TIPC_SKB_CB(skb)->retr_cnt++)
TIPC_SKB_CB(skb)->retr_stamp = jiffies;
} else {
/* retry with Gap ACK blocks if any */
if (n >= gack_cnt)
break;
nacked = ntohs(gacks[n].ack);
ngap = ntohs(gacks[n].gap);
n++;
goto next_gap_ack;
}
}
/* Renew last Gap ACK blocks for bc if needed */
if (bc_has_acked) {
if (this_ga) {
kfree(last_ga);
r->last_ga = this_ga;
r->last_gap = gap;
} else if (last_ga) {
if (less(acked, start)) {
si--;
offset = start - acked - 1;
} else if (less(acked, end)) {
acked = end;
}
if (si < last_ga->bgack_cnt) {
last_ga->start_index = si;
r->last_gap = offset;
} else {
kfree(last_ga);
r->last_ga = NULL;
r->last_gap = 0;
}
} else {
r->last_gap = 0;
}
r->acked = acked;
} else {
kfree(this_ga);
}
return qlen - skb_queue_len(&l->transmq);
}
/* tipc_link_build_state_msg: prepare link state message for transmission
*
* Note that sending of broadcast ack is coordinated among nodes, to reduce
* risk of ack storms towards the sender
*/
int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
{
if (!l)
return 0;
/* Broadcast ACK must be sent via a unicast link => defer to caller */
if (link_is_bc_rcvlink(l)) {
if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
return 0;
l->rcv_unacked = 0;
/* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
l->snd_nxt = l->rcv_nxt;
return TIPC_LINK_SND_STATE;
}
/* Unicast ACK */
l->rcv_unacked = 0;
l->stats.sent_acks++;
tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
return 0;
}
/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
*/
void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
{
int mtyp = RESET_MSG;
struct sk_buff *skb;
if (l->state == LINK_ESTABLISHING)
mtyp = ACTIVATE_MSG;
tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq);
/* Inform peer that this endpoint is going down if applicable */
skb = skb_peek_tail(xmitq);
if (skb && (l->state == LINK_RESET))
msg_set_peer_stopping(buf_msg(skb), 1);
}
/* tipc_link_build_nack_msg: prepare link nack message for transmission
* Note that sending of broadcast NACK is coordinated among nodes, to
* reduce the risk of NACK storms towards the sender
*/
static int tipc_link_build_nack_msg(struct tipc_link *l,
struct sk_buff_head *xmitq)
{
u32 def_cnt = ++l->stats.deferred_recv;
struct sk_buff_head *dfq = &l->deferdq;
u32 defq_len = skb_queue_len(dfq);
int match1, match2;
if (link_is_bc_rcvlink(l)) {
match1 = def_cnt & 0xf;
match2 = tipc_own_addr(l->net) & 0xf;
if (match1 == match2)
return TIPC_LINK_SND_STATE;
return 0;
}
if (defq_len >= 3 && !((defq_len - 3) % 16)) {
u16 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
tipc_link_build_proto_msg(l, STATE_MSG, 0, 0,
rcvgap, 0, 0, xmitq);
}
return 0;
}
/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
* @l: the link that should handle the message
* @skb: TIPC packet
* @xmitq: queue to place packets to be sent after this call
*/
int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
struct sk_buff_head *xmitq)
{
struct sk_buff_head *defq = &l->deferdq;
struct tipc_msg *hdr = buf_msg(skb);
u16 seqno, rcv_nxt, win_lim;
int released = 0;
int rc = 0;
/* Verify and update link state */
if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
return tipc_link_proto_rcv(l, skb, xmitq);
/* Don't send probe at next timeout expiration */
l->silent_intv_cnt = 0;
do {
hdr = buf_msg(skb);
seqno = msg_seqno(hdr);
rcv_nxt = l->rcv_nxt;
win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
if (unlikely(!tipc_link_is_up(l))) {
if (l->state == LINK_ESTABLISHING)
rc = TIPC_LINK_UP_EVT;
kfree_skb(skb);
break;
}
/* Drop if outside receive window */
if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
l->stats.duplicates++;
kfree_skb(skb);
break;
}
released += tipc_link_advance_transmq(l, l, msg_ack(hdr), 0,
NULL, NULL, NULL, NULL);
/* Defer delivery if sequence gap */
if (unlikely(seqno != rcv_nxt)) {
if (!__tipc_skb_queue_sorted(defq, seqno, skb))
l->stats.duplicates++;
rc |= tipc_link_build_nack_msg(l, xmitq);
break;
}
/* Deliver packet */
l->rcv_nxt++;
l->stats.recv_pkts++;
if (unlikely(msg_user(hdr) == TUNNEL_PROTOCOL))
rc |= tipc_link_tnl_rcv(l, skb, l->inputq);
else if (!tipc_data_input(l, skb, l->inputq))
rc |= tipc_link_input(l, skb, l->inputq, &l->reasm_buf);
if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
rc |= tipc_link_build_state_msg(l, xmitq);
if (unlikely(rc & ~TIPC_LINK_SND_STATE))
break;
} while ((skb = __tipc_skb_dequeue(defq, l->rcv_nxt)));
/* Forward queues and wake up waiting users */
if (released) {
tipc_link_update_cwin(l, released, 0);
tipc_link_advance_backlog(l, xmitq);
if (unlikely(!skb_queue_empty(&l->wakeupq)))
link_prepare_wakeup(l);
}
return rc;
}
static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
bool probe_reply, u16 rcvgap,
int tolerance, int priority,
struct sk_buff_head *xmitq)
{
struct tipc_mon_state *mstate = &l->mon_state;
struct sk_buff_head *dfq = &l->deferdq;
struct tipc_link *bcl = l->bc_rcvlink;
struct tipc_msg *hdr;
struct sk_buff *skb;
bool node_up = tipc_link_is_up(bcl);
u16 glen = 0, bc_rcvgap = 0;
int dlen = 0;
void *data;
/* Don't send protocol message during reset or link failover */
if (tipc_link_is_blocked(l))
return;
if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
return;
if ((probe || probe_reply) && !skb_queue_empty(dfq))
rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
tipc_max_domain_size + MAX_GAP_ACK_BLKS_SZ,
l->addr, tipc_own_addr(l->net), 0, 0, 0);
if (!skb)
return;
hdr = buf_msg(skb);
data = msg_data(hdr);
msg_set_session(hdr, l->session);
msg_set_bearer_id(hdr, l->bearer_id);
msg_set_net_plane(hdr, l->net_plane);
msg_set_next_sent(hdr, l->snd_nxt);
msg_set_ack(hdr, l->rcv_nxt - 1);
msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
msg_set_bc_ack_invalid(hdr, !node_up);
msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
msg_set_link_tolerance(hdr, tolerance);
msg_set_linkprio(hdr, priority);
msg_set_redundant_link(hdr, node_up);
msg_set_seq_gap(hdr, 0);
msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
if (mtyp == STATE_MSG) {
if (l->peer_caps & TIPC_LINK_PROTO_SEQNO)
msg_set_seqno(hdr, l->snd_nxt_state++);
msg_set_seq_gap(hdr, rcvgap);
bc_rcvgap = link_bc_rcv_gap(bcl);
msg_set_bc_gap(hdr, bc_rcvgap);
msg_set_probe(hdr, probe);
msg_set_is_keepalive(hdr, probe || probe_reply);
if (l->peer_caps & TIPC_GAP_ACK_BLOCK)
glen = tipc_build_gap_ack_blks(l, hdr);
tipc_mon_prep(l->net, data + glen, &dlen, mstate, l->bearer_id);
msg_set_size(hdr, INT_H_SIZE + glen + dlen);
skb_trim(skb, INT_H_SIZE + glen + dlen);
l->stats.sent_states++;
l->rcv_unacked = 0;
} else {
/* RESET_MSG or ACTIVATE_MSG */
if (mtyp == ACTIVATE_MSG) {
msg_set_dest_session_valid(hdr, 1);
msg_set_dest_session(hdr, l->peer_session);
}
msg_set_max_pkt(hdr, l->advertised_mtu);
strcpy(data, l->if_name);
msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
}
if (probe)
l->stats.sent_probes++;
if (rcvgap)
l->stats.sent_nacks++;
if (bc_rcvgap)
bcl->stats.sent_nacks++;
skb->priority = TC_PRIO_CONTROL;
__skb_queue_tail(xmitq, skb);
trace_tipc_proto_build(skb, false, l->name);
}
void tipc_link_create_dummy_tnl_msg(struct tipc_link *l,
struct sk_buff_head *xmitq)
{
u32 onode = tipc_own_addr(l->net);
struct tipc_msg *hdr, *ihdr;
struct sk_buff_head tnlq;
struct sk_buff *skb;
u32 dnode = l->addr;
__skb_queue_head_init(&tnlq);
skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG,
INT_H_SIZE, BASIC_H_SIZE,
dnode, onode, 0, 0, 0);
if (!skb) {
pr_warn("%sunable to create tunnel packet\n", link_co_err);
return;
}
hdr = buf_msg(skb);
msg_set_msgcnt(hdr, 1);
msg_set_bearer_id(hdr, l->peer_bearer_id);
ihdr = (struct tipc_msg *)msg_data(hdr);
tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
BASIC_H_SIZE, dnode);
msg_set_errcode(ihdr, TIPC_ERR_NO_PORT);
__skb_queue_tail(&tnlq, skb);
tipc_link_xmit(l, &tnlq, xmitq);
}
/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
* with contents of the link's transmit and backlog queues.
*/
void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
int mtyp, struct sk_buff_head *xmitq)
{
struct sk_buff_head *fdefq = &tnl->failover_deferdq;
struct sk_buff *skb, *tnlskb;
struct tipc_msg *hdr, tnlhdr;
struct sk_buff_head *queue = &l->transmq;
struct sk_buff_head tmpxq, tnlq, frags;
u16 pktlen, pktcnt, seqno = l->snd_nxt;
bool pktcnt_need_update = false;
u16 syncpt;
int rc;
if (!tnl)
return;
__skb_queue_head_init(&tnlq);
/* Link Synching:
* From now on, send only one single ("dummy") SYNCH message
* to peer. The SYNCH message does not contain any data, just
* a header conveying the synch point to the peer.
*/
if (mtyp == SYNCH_MSG && (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
tnlskb = tipc_msg_create(TUNNEL_PROTOCOL, SYNCH_MSG,
INT_H_SIZE, 0, l->addr,
tipc_own_addr(l->net),
0, 0, 0);
if (!tnlskb) {
pr_warn("%sunable to create dummy SYNCH_MSG\n",
link_co_err);
return;
}
hdr = buf_msg(tnlskb);
syncpt = l->snd_nxt + skb_queue_len(&l->backlogq) - 1;
msg_set_syncpt(hdr, syncpt);
msg_set_bearer_id(hdr, l->peer_bearer_id);
__skb_queue_tail(&tnlq, tnlskb);
tipc_link_xmit(tnl, &tnlq, xmitq);
return;
}
__skb_queue_head_init(&tmpxq);
__skb_queue_head_init(&frags);
/* At least one packet required for safe algorithm => add dummy */
skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
0, 0, TIPC_ERR_NO_PORT);
if (!skb) {
pr_warn("%sunable to create tunnel packet\n", link_co_err);
return;
}
__skb_queue_tail(&tnlq, skb);
tipc_link_xmit(l, &tnlq, &tmpxq);
__skb_queue_purge(&tmpxq);
/* Initialize reusable tunnel packet header */
tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
mtyp, INT_H_SIZE, l->addr);
if (mtyp == SYNCH_MSG)
pktcnt = l->snd_nxt - buf_seqno(skb_peek(&l->transmq));
else
pktcnt = skb_queue_len(&l->transmq);
pktcnt += skb_queue_len(&l->backlogq);
msg_set_msgcnt(&tnlhdr, pktcnt);
msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
tnl:
/* Wrap each packet into a tunnel packet */
skb_queue_walk(queue, skb) {
hdr = buf_msg(skb);
if (queue == &l->backlogq)
msg_set_seqno(hdr, seqno++);
pktlen = msg_size(hdr);
/* Tunnel link MTU is not large enough? This could be
* due to:
* 1) Link MTU has just changed or set differently;
* 2) Or FAILOVER on the top of a SYNCH message
*
* The 2nd case should not happen if peer supports
* TIPC_TUNNEL_ENHANCED
*/
if (pktlen > tnl->mtu - INT_H_SIZE) {
if (mtyp == FAILOVER_MSG &&
(tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
rc = tipc_msg_fragment(skb, &tnlhdr, tnl->mtu,
&frags);
if (rc) {
pr_warn("%sunable to frag msg: rc %d\n",
link_co_err, rc);
return;
}
pktcnt += skb_queue_len(&frags) - 1;
pktcnt_need_update = true;
skb_queue_splice_tail_init(&frags, &tnlq);
continue;
}
/* Unluckily, peer doesn't have TIPC_TUNNEL_ENHANCED
* => Just warn it and return!
*/
pr_warn_ratelimited("%stoo large msg <%d, %d>: %d!\n",
link_co_err, msg_user(hdr),
msg_type(hdr), msg_size(hdr));
return;
}
msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
if (!tnlskb) {
pr_warn("%sunable to send packet\n", link_co_err);
return;
}
skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
__skb_queue_tail(&tnlq, tnlskb);
}
if (queue != &l->backlogq) {
queue = &l->backlogq;
goto tnl;
}
if (pktcnt_need_update)
skb_queue_walk(&tnlq, skb) {
hdr = buf_msg(skb);
msg_set_msgcnt(hdr, pktcnt);
}
tipc_link_xmit(tnl, &tnlq, xmitq);
if (mtyp == FAILOVER_MSG) {
tnl->drop_point = l->rcv_nxt;
tnl->failover_reasm_skb = l->reasm_buf;
l->reasm_buf = NULL;
/* Failover the link's deferdq */
if (unlikely(!skb_queue_empty(fdefq))) {
pr_warn("Link failover deferdq not empty: %d!\n",
skb_queue_len(fdefq));
__skb_queue_purge(fdefq);
}
skb_queue_splice_init(&l->deferdq, fdefq);
}
}
/**
* tipc_link_failover_prepare() - prepare tnl for link failover
*
* This is a special version of the precursor - tipc_link_tnl_prepare(),
* see the tipc_node_link_failover() for details
*
* @l: failover link
* @tnl: tunnel link
* @xmitq: queue for messages to be xmited
*/
void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl,
struct sk_buff_head *xmitq)
{
struct sk_buff_head *fdefq = &tnl->failover_deferdq;
tipc_link_create_dummy_tnl_msg(tnl, xmitq);
/* This failover link endpoint was never established before,
* so it has not received anything from peer.
* Otherwise, it must be a normal failover situation or the
* node has entered SELF_DOWN_PEER_LEAVING and both peer nodes
* would have to start over from scratch instead.
*/
tnl->drop_point = 1;
tnl->failover_reasm_skb = NULL;
/* Initiate the link's failover deferdq */
if (unlikely(!skb_queue_empty(fdefq))) {
pr_warn("Link failover deferdq not empty: %d!\n",
skb_queue_len(fdefq));
__skb_queue_purge(fdefq);
}
}
/* tipc_link_validate_msg(): validate message against current link state
* Returns true if message should be accepted, otherwise false
*/
bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr)
{
u16 curr_session = l->peer_session;
u16 session = msg_session(hdr);
int mtyp = msg_type(hdr);
if (msg_user(hdr) != LINK_PROTOCOL)
return true;
switch (mtyp) {
case RESET_MSG:
if (!l->in_session)
return true;
/* Accept only RESET with new session number */
return more(session, curr_session);
case ACTIVATE_MSG:
if (!l->in_session)
return true;
/* Accept only ACTIVATE with new or current session number */
return !less(session, curr_session);
case STATE_MSG:
/* Accept only STATE with current session number */
if (!l->in_session)
return false;
if (session != curr_session)
return false;
/* Extra sanity check */
if (!tipc_link_is_up(l) && msg_ack(hdr))
return false;
if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO))
return true;
/* Accept only STATE with new sequence number */
return !less(msg_seqno(hdr), l->rcv_nxt_state);
default:
return false;
}
}
/* tipc_link_proto_rcv(): receive link level protocol message :
* Note that network plane id propagates through the network, and may
* change at any time. The node with lowest numerical id determines
* network plane
*/
static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
struct sk_buff_head *xmitq)
{
struct tipc_msg *hdr = buf_msg(skb);
struct tipc_gap_ack_blks *ga = NULL;
bool reply = msg_probe(hdr), retransmitted = false;
u32 dlen = msg_data_sz(hdr), glen = 0, msg_max;
u16 peers_snd_nxt = msg_next_sent(hdr);
u16 peers_tol = msg_link_tolerance(hdr);
u16 peers_prio = msg_linkprio(hdr);
u16 gap = msg_seq_gap(hdr);
u16 ack = msg_ack(hdr);
u16 rcv_nxt = l->rcv_nxt;
u16 rcvgap = 0;
int mtyp = msg_type(hdr);
int rc = 0, released;
char *if_name;
void *data;
trace_tipc_proto_rcv(skb, false, l->name);
if (dlen > U16_MAX)
goto exit;
if (tipc_link_is_blocked(l) || !xmitq)
goto exit;
if (tipc_own_addr(l->net) > msg_prevnode(hdr))
l->net_plane = msg_net_plane(hdr);
if (skb_linearize(skb))
goto exit;
hdr = buf_msg(skb);
data = msg_data(hdr);
if (!tipc_link_validate_msg(l, hdr)) {
trace_tipc_skb_dump(skb, false, "PROTO invalid (1)!");
trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (1)!");
goto exit;
}
switch (mtyp) {
case RESET_MSG:
case ACTIVATE_MSG:
msg_max = msg_max_pkt(hdr);
if (msg_max < tipc_bearer_min_mtu(l->net, l->bearer_id))
break;
/* Complete own link name with peer's interface name */
if_name = strrchr(l->name, ':') + 1;
if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
break;
if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
break;
strncpy(if_name, data, TIPC_MAX_IF_NAME);
/* Update own tolerance if peer indicates a non-zero value */
if (tipc_in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
l->tolerance = peers_tol;
l->bc_rcvlink->tolerance = peers_tol;
}
/* Update own priority if peer's priority is higher */
if (tipc_in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
l->priority = peers_prio;
/* If peer is going down we want full re-establish cycle */
if (msg_peer_stopping(hdr)) {
rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
break;
}
/* If this endpoint was re-created while peer was ESTABLISHING
* it doesn't know current session number. Force re-synch.
*/
if (mtyp == ACTIVATE_MSG && msg_dest_session_valid(hdr) &&
l->session != msg_dest_session(hdr)) {
if (less(l->session, msg_dest_session(hdr)))
l->session = msg_dest_session(hdr) + 1;
break;
}
/* ACTIVATE_MSG serves as PEER_RESET if link is already down */
if (mtyp == RESET_MSG || !tipc_link_is_up(l))
rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
/* ACTIVATE_MSG takes up link if it was already locally reset */
if (mtyp == ACTIVATE_MSG && l->state == LINK_ESTABLISHING)
rc = TIPC_LINK_UP_EVT;
l->peer_session = msg_session(hdr);
l->in_session = true;
l->peer_bearer_id = msg_bearer_id(hdr);
if (l->mtu > msg_max)
l->mtu = msg_max;
break;
case STATE_MSG:
/* Validate Gap ACK blocks, drop if invalid */
glen = tipc_get_gap_ack_blks(&ga, l, hdr, true);
if (glen > dlen)
break;
l->rcv_nxt_state = msg_seqno(hdr) + 1;
/* Update own tolerance if peer indicates a non-zero value */
if (tipc_in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
l->tolerance = peers_tol;
l->bc_rcvlink->tolerance = peers_tol;
}
/* Update own prio if peer indicates a different value */
if ((peers_prio != l->priority) &&
tipc_in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
l->priority = peers_prio;
rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
}
l->silent_intv_cnt = 0;
l->stats.recv_states++;
if (msg_probe(hdr))
l->stats.recv_probes++;
if (!tipc_link_is_up(l)) {
if (l->state == LINK_ESTABLISHING)
rc = TIPC_LINK_UP_EVT;
break;
}
tipc_mon_rcv(l->net, data + glen, dlen - glen, l->addr,
&l->mon_state, l->bearer_id);
/* Send NACK if peer has sent pkts we haven't received yet */
if ((reply || msg_is_keepalive(hdr)) &&
more(peers_snd_nxt, rcv_nxt) &&
!tipc_link_is_synching(l) &&
skb_queue_empty(&l->deferdq))
rcvgap = peers_snd_nxt - l->rcv_nxt;
if (rcvgap || reply)
tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
rcvgap, 0, 0, xmitq);
released = tipc_link_advance_transmq(l, l, ack, gap, ga, xmitq,
&retransmitted, &rc);
if (gap)
l->stats.recv_nacks++;
if (released || retransmitted)
tipc_link_update_cwin(l, released, retransmitted);
if (released)
tipc_link_advance_backlog(l, xmitq);
if (unlikely(!skb_queue_empty(&l->wakeupq)))
link_prepare_wakeup(l);
}
exit:
kfree_skb(skb);
return rc;
}
/* tipc_link_build_bc_proto_msg() - create broadcast protocol message
*/
static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
u16 peers_snd_nxt,
struct sk_buff_head *xmitq)
{
struct sk_buff *skb;
struct tipc_msg *hdr;
struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
u16 ack = l->rcv_nxt - 1;
u16 gap_to = peers_snd_nxt - 1;
skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
if (!skb)
return false;
hdr = buf_msg(skb);
msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
msg_set_bcast_ack(hdr, ack);
msg_set_bcgap_after(hdr, ack);
if (dfrd_skb)
gap_to = buf_seqno(dfrd_skb) - 1;
msg_set_bcgap_to(hdr, gap_to);
msg_set_non_seq(hdr, bcast);
__skb_queue_tail(xmitq, skb);
return true;
}
/* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
*
* Give a newly added peer node the sequence number where it should
* start receiving and acking broadcast packets.
*/
static void tipc_link_build_bc_init_msg(struct tipc_link *l,
struct sk_buff_head *xmitq)
{
struct sk_buff_head list;
__skb_queue_head_init(&list);
if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
return;
msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
tipc_link_xmit(l, &list, xmitq);
}
/* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
*/
void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
{
int mtyp = msg_type(hdr);
u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
if (tipc_link_is_up(l))
return;
if (msg_user(hdr) == BCAST_PROTOCOL) {
l->rcv_nxt = peers_snd_nxt;
l->state = LINK_ESTABLISHED;
return;
}
if (l->peer_caps & TIPC_BCAST_SYNCH)
return;
if (msg_peer_node_is_up(hdr))
return;
/* Compatibility: accept older, less safe initial synch data */
if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
l->rcv_nxt = peers_snd_nxt;
}
/* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
*/
int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
struct sk_buff_head *xmitq)
{
u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
int rc = 0;
if (!tipc_link_is_up(l))
return rc;
if (!msg_peer_node_is_up(hdr))
return rc;
/* Open when peer acknowledges our bcast init msg (pkt #1) */
if (msg_ack(hdr))
l->bc_peer_is_up = true;
if (!l->bc_peer_is_up)
return rc;
/* Ignore if peers_snd_nxt goes beyond receive window */
if (more(peers_snd_nxt, l->rcv_nxt + l->window))
return rc;
l->snd_nxt = peers_snd_nxt;
if (link_bc_rcv_gap(l))
rc |= TIPC_LINK_SND_STATE;
/* Return now if sender supports nack via STATE messages */
if (l->peer_caps & TIPC_BCAST_STATE_NACK)
return rc;
/* Otherwise, be backwards compatible */
if (!more(peers_snd_nxt, l->rcv_nxt)) {
l->nack_state = BC_NACK_SND_CONDITIONAL;
return 0;
}
/* Don't NACK if one was recently sent or peeked */
if (l->nack_state == BC_NACK_SND_SUPPRESS) {
l->nack_state = BC_NACK_SND_UNCONDITIONAL;
return 0;
}
/* Conditionally delay NACK sending until next synch rcv */
if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
l->nack_state = BC_NACK_SND_UNCONDITIONAL;
if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
return 0;
}
/* Send NACK now but suppress next one */
tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
l->nack_state = BC_NACK_SND_SUPPRESS;
return 0;
}
int tipc_link_bc_ack_rcv(struct tipc_link *r, u16 acked, u16 gap,
struct tipc_gap_ack_blks *ga,
struct sk_buff_head *xmitq,
struct sk_buff_head *retrq)
{
struct tipc_link *l = r->bc_sndlink;
bool unused = false;
int rc = 0;
if (!tipc_link_is_up(r) || !r->bc_peer_is_up)
return 0;
if (gap) {
l->stats.recv_nacks++;
r->stats.recv_nacks++;
}
if (less(acked, r->acked) || (acked == r->acked && !gap && !ga))
return 0;
trace_tipc_link_bc_ack(r, acked, gap, &l->transmq);
tipc_link_advance_transmq(l, r, acked, gap, ga, retrq, &unused, &rc);
tipc_link_advance_backlog(l, xmitq);
if (unlikely(!skb_queue_empty(&l->wakeupq)))
link_prepare_wakeup(l);
return rc;
}
/* tipc_link_bc_nack_rcv(): receive broadcast nack message
* This function is here for backwards compatibility, since
* no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
*/
int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
struct sk_buff_head *xmitq)
{
struct tipc_msg *hdr = buf_msg(skb);
u32 dnode = msg_destnode(hdr);
int mtyp = msg_type(hdr);
u16 acked = msg_bcast_ack(hdr);
u16 from = acked + 1;
u16 to = msg_bcgap_to(hdr);
u16 peers_snd_nxt = to + 1;
int rc = 0;
kfree_skb(skb);
if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
return 0;
if (mtyp != STATE_MSG)
return 0;
if (dnode == tipc_own_addr(l->net)) {
rc = tipc_link_bc_ack_rcv(l, acked, to - acked, NULL, xmitq,
xmitq);
l->stats.recv_nacks++;
return rc;
}
/* Msg for other node => suppress own NACK at next sync if applicable */
if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
l->nack_state = BC_NACK_SND_SUPPRESS;
return 0;
}
void tipc_link_set_queue_limits(struct tipc_link *l, u32 min_win, u32 max_win)
{
int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
l->min_win = min_win;
l->ssthresh = max_win;
l->max_win = max_win;
l->window = min_win;
l->backlog[TIPC_LOW_IMPORTANCE].limit = min_win * 2;
l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = min_win * 4;
l->backlog[TIPC_HIGH_IMPORTANCE].limit = min_win * 6;
l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = min_win * 8;
l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
}
/**
* tipc_link_reset_stats - reset link statistics
* @l: pointer to link
*/
void tipc_link_reset_stats(struct tipc_link *l)
{
memset(&l->stats, 0, sizeof(l->stats));
}
static void link_print(struct tipc_link *l, const char *str)
{
struct sk_buff *hskb = skb_peek(&l->transmq);
u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
u16 tail = l->snd_nxt - 1;
pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
skb_queue_len(&l->transmq), head, tail,
skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
}
/* Parse and validate nested (link) properties valid for media, bearer and link
*/
int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
{
int err;
err = nla_parse_nested_deprecated(props, TIPC_NLA_PROP_MAX, prop,
tipc_nl_prop_policy, NULL);
if (err)
return err;
if (props[TIPC_NLA_PROP_PRIO]) {
u32 prio;
prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
if (prio > TIPC_MAX_LINK_PRI)
return -EINVAL;
}
if (props[TIPC_NLA_PROP_TOL]) {
u32 tol;
tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
return -EINVAL;
}
if (props[TIPC_NLA_PROP_WIN]) {
u32 max_win;
max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
if (max_win < TIPC_DEF_LINK_WIN || max_win > TIPC_MAX_LINK_WIN)
return -EINVAL;
}
return 0;
}
static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
{
int i;
struct nlattr *stats;
struct nla_map {
u32 key;
u32 val;
};
struct nla_map map[] = {
{TIPC_NLA_STATS_RX_INFO, 0},
{TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
{TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
{TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
{TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
{TIPC_NLA_STATS_TX_INFO, 0},
{TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
{TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
{TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
{TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
{TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
s->msg_length_counts : 1},
{TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
{TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
{TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
{TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
{TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
{TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
{TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
{TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
{TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
{TIPC_NLA_STATS_RX_STATES, s->recv_states},
{TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
{TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
{TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
{TIPC_NLA_STATS_TX_STATES, s->sent_states},
{TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
{TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
{TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
{TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
{TIPC_NLA_STATS_DUPLICATES, s->duplicates},
{TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
{TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
{TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
(s->accu_queue_sz / s->queue_sz_counts) : 0}
};
stats = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
if (!stats)
return -EMSGSIZE;
for (i = 0; i < ARRAY_SIZE(map); i++)
if (nla_put_u32(skb, map[i].key, map[i].val))
goto msg_full;
nla_nest_end(skb, stats);
return 0;
msg_full:
nla_nest_cancel(skb, stats);
return -EMSGSIZE;
}
/* Caller should hold appropriate locks to protect the link */
int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
struct tipc_link *link, int nlflags)
{
u32 self = tipc_own_addr(net);
struct nlattr *attrs;
struct nlattr *prop;
void *hdr;
int err;
hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
nlflags, TIPC_NL_LINK_GET);
if (!hdr)
return -EMSGSIZE;
attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
if (!attrs)
goto msg_full;
if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
goto attr_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self)))
goto attr_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
goto attr_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
goto attr_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
goto attr_msg_full;
if (tipc_link_is_up(link))
if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
goto attr_msg_full;
if (link->active)
if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
goto attr_msg_full;
prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
if (!prop)
goto attr_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
goto prop_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
goto prop_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
link->window))
goto prop_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
goto prop_msg_full;
nla_nest_end(msg->skb, prop);
err = __tipc_nl_add_stats(msg->skb, &link->stats);
if (err)
goto attr_msg_full;
nla_nest_end(msg->skb, attrs);
genlmsg_end(msg->skb, hdr);
return 0;
prop_msg_full:
nla_nest_cancel(msg->skb, prop);
attr_msg_full:
nla_nest_cancel(msg->skb, attrs);
msg_full:
genlmsg_cancel(msg->skb, hdr);
return -EMSGSIZE;
}
static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
struct tipc_stats *stats)
{
int i;
struct nlattr *nest;
struct nla_map {
__u32 key;
__u32 val;
};
struct nla_map map[] = {
{TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
{TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
{TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
{TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
{TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
{TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
{TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
{TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
{TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
{TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
{TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
{TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
{TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
{TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
{TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
{TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
{TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
{TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
{TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
(stats->accu_queue_sz / stats->queue_sz_counts) : 0}
};
nest = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
if (!nest)
return -EMSGSIZE;
for (i = 0; i < ARRAY_SIZE(map); i++)
if (nla_put_u32(skb, map[i].key, map[i].val))
goto msg_full;
nla_nest_end(skb, nest);
return 0;
msg_full:
nla_nest_cancel(skb, nest);
return -EMSGSIZE;
}
int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg,
struct tipc_link *bcl)
{
int err;
void *hdr;
struct nlattr *attrs;
struct nlattr *prop;
u32 bc_mode = tipc_bcast_get_mode(net);
u32 bc_ratio = tipc_bcast_get_broadcast_ratio(net);
if (!bcl)
return 0;
tipc_bcast_lock(net);
hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
NLM_F_MULTI, TIPC_NL_LINK_GET);
if (!hdr) {
tipc_bcast_unlock(net);
return -EMSGSIZE;
}
attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
if (!attrs)
goto msg_full;
/* The broadcast link is always up */
if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
goto attr_msg_full;
if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
goto attr_msg_full;
if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
goto attr_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
goto attr_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
goto attr_msg_full;
prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
if (!prop)
goto attr_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->max_win))
goto prop_msg_full;
if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST, bc_mode))
goto prop_msg_full;
if (bc_mode & BCLINK_MODE_SEL)
if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST_RATIO,
bc_ratio))
goto prop_msg_full;
nla_nest_end(msg->skb, prop);
err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
if (err)
goto attr_msg_full;
tipc_bcast_unlock(net);
nla_nest_end(msg->skb, attrs);
genlmsg_end(msg->skb, hdr);
return 0;
prop_msg_full:
nla_nest_cancel(msg->skb, prop);
attr_msg_full:
nla_nest_cancel(msg->skb, attrs);
msg_full:
tipc_bcast_unlock(net);
genlmsg_cancel(msg->skb, hdr);
return -EMSGSIZE;
}
void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
struct sk_buff_head *xmitq)
{
l->tolerance = tol;
if (l->bc_rcvlink)
l->bc_rcvlink->tolerance = tol;
if (tipc_link_is_up(l))
tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
}
void tipc_link_set_prio(struct tipc_link *l, u32 prio,
struct sk_buff_head *xmitq)
{
l->priority = prio;
tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq);
}
void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
{
l->abort_limit = limit;
}
/**
* tipc_link_dump - dump TIPC link data
* @l: tipc link to be dumped
* @dqueues: bitmask to decide if any link queue to be dumped?
* - TIPC_DUMP_NONE: don't dump link queues
* - TIPC_DUMP_TRANSMQ: dump link transmq queue
* - TIPC_DUMP_BACKLOGQ: dump link backlog queue
* - TIPC_DUMP_DEFERDQ: dump link deferd queue
* - TIPC_DUMP_INPUTQ: dump link input queue
* - TIPC_DUMP_WAKEUP: dump link wakeup queue
* - TIPC_DUMP_ALL: dump all the link queues above
* @buf: returned buffer of dump data in format
*/
int tipc_link_dump(struct tipc_link *l, u16 dqueues, char *buf)
{
int i = 0;
size_t sz = (dqueues) ? LINK_LMAX : LINK_LMIN;
struct sk_buff_head *list;
struct sk_buff *hskb, *tskb;
u32 len;
if (!l) {
i += scnprintf(buf, sz, "link data: (null)\n");
return i;
}
i += scnprintf(buf, sz, "link data: %x", l->addr);
i += scnprintf(buf + i, sz - i, " %x", l->state);
i += scnprintf(buf + i, sz - i, " %u", l->in_session);
i += scnprintf(buf + i, sz - i, " %u", l->session);
i += scnprintf(buf + i, sz - i, " %u", l->peer_session);
i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt);
i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt);
i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt_state);
i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt_state);
i += scnprintf(buf + i, sz - i, " %x", l->peer_caps);
i += scnprintf(buf + i, sz - i, " %u", l->silent_intv_cnt);
i += scnprintf(buf + i, sz - i, " %u", l->rst_cnt);
i += scnprintf(buf + i, sz - i, " %u", 0);
i += scnprintf(buf + i, sz - i, " %u", 0);
i += scnprintf(buf + i, sz - i, " %u", l->acked);
list = &l->transmq;
len = skb_queue_len(list);
hskb = skb_peek(list);
tskb = skb_peek_tail(list);
i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
(hskb) ? msg_seqno(buf_msg(hskb)) : 0,
(tskb) ? msg_seqno(buf_msg(tskb)) : 0);
list = &l->deferdq;
len = skb_queue_len(list);
hskb = skb_peek(list);
tskb = skb_peek_tail(list);
i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
(hskb) ? msg_seqno(buf_msg(hskb)) : 0,
(tskb) ? msg_seqno(buf_msg(tskb)) : 0);
list = &l->backlogq;
len = skb_queue_len(list);
hskb = skb_peek(list);
tskb = skb_peek_tail(list);
i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
(hskb) ? msg_seqno(buf_msg(hskb)) : 0,
(tskb) ? msg_seqno(buf_msg(tskb)) : 0);
list = l->inputq;
len = skb_queue_len(list);
hskb = skb_peek(list);
tskb = skb_peek_tail(list);
i += scnprintf(buf + i, sz - i, " | %u %u %u\n", len,
(hskb) ? msg_seqno(buf_msg(hskb)) : 0,
(tskb) ? msg_seqno(buf_msg(tskb)) : 0);
if (dqueues & TIPC_DUMP_TRANSMQ) {
i += scnprintf(buf + i, sz - i, "transmq: ");
i += tipc_list_dump(&l->transmq, false, buf + i);
}
if (dqueues & TIPC_DUMP_BACKLOGQ) {
i += scnprintf(buf + i, sz - i,
"backlogq: <%u %u %u %u %u>, ",
l->backlog[TIPC_LOW_IMPORTANCE].len,
l->backlog[TIPC_MEDIUM_IMPORTANCE].len,
l->backlog[TIPC_HIGH_IMPORTANCE].len,
l->backlog[TIPC_CRITICAL_IMPORTANCE].len,
l->backlog[TIPC_SYSTEM_IMPORTANCE].len);
i += tipc_list_dump(&l->backlogq, false, buf + i);
}
if (dqueues & TIPC_DUMP_DEFERDQ) {
i += scnprintf(buf + i, sz - i, "deferdq: ");
i += tipc_list_dump(&l->deferdq, false, buf + i);
}
if (dqueues & TIPC_DUMP_INPUTQ) {
i += scnprintf(buf + i, sz - i, "inputq: ");
i += tipc_list_dump(l->inputq, false, buf + i);
}
if (dqueues & TIPC_DUMP_WAKEUP) {
i += scnprintf(buf + i, sz - i, "wakeup: ");
i += tipc_list_dump(&l->wakeupq, false, buf + i);
}
return i;
}
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