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Diffstat (limited to 'net/tipc/link.c')
| -rw-r--r-- | net/tipc/link.c | 3009 |
1 files changed, 3009 insertions, 0 deletions
diff --git a/net/tipc/link.c b/net/tipc/link.c new file mode 100644 index 000000000..8715c9b05 --- /dev/null +++ b/net/tipc/link.c @@ -0,0 +1,3009 @@ +/* + * 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 + * @media_addr: media address to use when sending messages over link + * @timer: link timer + * @net: pointer to namespace struct + * @refcnt: reference counter for permanent references (owner node & timer) + * @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 + * @proto_msg: template for control messages generated by link + * @pmsg: convenience pointer to "proto_msg" field + * @priority: current link priority + * @net_plane: current link network plane ('A' through 'H') + * @mon_state: cookie with information needed by link monitor + * @backlog_limit: backlog queue congestion thresholds (indexed by importance) + * @exp_msg_count: # of tunnelled messages expected during link changeover + * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset + * @mtu: current maximum packet size for this link + * @advertised_mtu: advertised own mtu when link is being established + * @transmitq: queue for sent, non-acked messages + * @backlogq: queue for messages waiting to be sent + * @snt_nxt: next sequence number to use for outbound messages + * @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 + * @deferred_queue: deferred queue saved OOS b'cast message received from node + * @unacked_window: # of inbound messages rx'd without ack'ing back to peer + * @inputq: buffer queue for messages to be delivered upwards + * @namedq: buffer queue for name table messages to be delivered upwards + * @next_out: ptr to first unsent outbound message in queue + * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate + * @long_msg_seq_no: next identifier to use for outbound fragmented messages + * @reasm_buf: head of partially reassembled inbound message fragments + * @bc_rcvr: marks that this is a broadcast receiver link + * @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 +}; + +/* Link FSM state checking routines + */ +static int link_is_up(struct tipc_link *l) +{ + return l->state & (LINK_ESTABLISHED | LINK_SYNCHING); +} + +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 link_is_up(l); +} + +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 (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(!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 = 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 (!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 (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 (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 || !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 (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) && + 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 (!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 (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 (!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 (!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 (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; +} |