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|
/*
* Copyright (c) 2016-2019 Cisco and/or its affiliates.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @file
* @brief TCP host stack utilities
*/
#include <vnet/tcp/tcp.h>
#include <vnet/tcp/tcp_inlines.h>
#include <vnet/session/session.h>
#include <vnet/fib/fib.h>
#include <vnet/dpo/load_balance.h>
#include <math.h>
tcp_main_t tcp_main;
typedef struct
{
fib_protocol_t nh_proto;
vnet_link_t link_type;
ip46_address_t ip;
u32 sw_if_index;
u8 is_add;
} tcp_add_del_adj_args_t;
static void
tcp_add_del_adj_cb (tcp_add_del_adj_args_t * args)
{
u32 ai;
if (args->is_add)
{
adj_nbr_add_or_lock (args->nh_proto, args->link_type, &args->ip,
args->sw_if_index);
}
else
{
ai = adj_nbr_find (FIB_PROTOCOL_IP6, VNET_LINK_IP6, &args->ip,
args->sw_if_index);
if (ai != ADJ_INDEX_INVALID)
adj_unlock (ai);
}
}
static void
tcp_add_del_adjacency (tcp_connection_t * tc, u8 is_add)
{
tcp_add_del_adj_args_t args = {
.nh_proto = FIB_PROTOCOL_IP6,
.link_type = VNET_LINK_IP6,
.ip = tc->c_rmt_ip,
.sw_if_index = tc->sw_if_index,
.is_add = is_add
};
vlib_rpc_call_main_thread (tcp_add_del_adj_cb, (u8 *) & args,
sizeof (args));
}
static void
tcp_cc_init (tcp_connection_t * tc)
{
tc->cc_algo->init (tc);
}
static void
tcp_cc_cleanup (tcp_connection_t * tc)
{
if (tc->cc_algo->cleanup)
tc->cc_algo->cleanup (tc);
}
void
tcp_cc_algo_register (tcp_cc_algorithm_type_e type,
const tcp_cc_algorithm_t * vft)
{
tcp_main_t *tm = vnet_get_tcp_main ();
vec_validate (tm->cc_algos, type);
tm->cc_algos[type] = *vft;
hash_set_mem (tm->cc_algo_by_name, vft->name, type);
}
tcp_cc_algorithm_t *
tcp_cc_algo_get (tcp_cc_algorithm_type_e type)
{
tcp_main_t *tm = vnet_get_tcp_main ();
return &tm->cc_algos[type];
}
tcp_cc_algorithm_type_e
tcp_cc_algo_new_type (const tcp_cc_algorithm_t * vft)
{
tcp_main_t *tm = vnet_get_tcp_main ();
tcp_cc_algo_register (++tm->cc_last_type, vft);
return tm->cc_last_type;
}
static u32
tcp_connection_bind (u32 session_index, transport_endpoint_t * lcl)
{
tcp_main_t *tm = &tcp_main;
tcp_connection_t *listener;
void *iface_ip;
pool_get (tm->listener_pool, listener);
clib_memset (listener, 0, sizeof (*listener));
listener->c_c_index = listener - tm->listener_pool;
listener->c_lcl_port = lcl->port;
/* If we are provided a sw_if_index, bind using one of its ips */
if (ip_is_zero (&lcl->ip, 1) && lcl->sw_if_index != ENDPOINT_INVALID_INDEX)
{
if ((iface_ip = ip_interface_get_first_ip (lcl->sw_if_index,
lcl->is_ip4)))
ip_set (&lcl->ip, iface_ip, lcl->is_ip4);
}
ip_copy (&listener->c_lcl_ip, &lcl->ip, lcl->is_ip4);
listener->c_is_ip4 = lcl->is_ip4;
listener->c_proto = TRANSPORT_PROTO_TCP;
listener->c_s_index = session_index;
listener->c_fib_index = lcl->fib_index;
listener->state = TCP_STATE_LISTEN;
listener->cc_algo = tcp_cc_algo_get (tcp_cfg.cc_algo);
tcp_connection_timers_init (listener);
TCP_EVT (TCP_EVT_BIND, listener);
return listener->c_c_index;
}
static u32
tcp_session_bind (u32 session_index, transport_endpoint_t * tep)
{
return tcp_connection_bind (session_index, tep);
}
static void
tcp_connection_unbind (u32 listener_index)
{
tcp_main_t *tm = vnet_get_tcp_main ();
tcp_connection_t *tc;
tc = pool_elt_at_index (tm->listener_pool, listener_index);
TCP_EVT (TCP_EVT_UNBIND, tc);
/* Poison the entry */
if (CLIB_DEBUG > 0)
clib_memset (tc, 0xFA, sizeof (*tc));
pool_put_index (tm->listener_pool, listener_index);
}
static u32
tcp_session_unbind (u32 listener_index)
{
tcp_connection_unbind (listener_index);
return 0;
}
static transport_connection_t *
tcp_session_get_listener (u32 listener_index)
{
tcp_main_t *tm = vnet_get_tcp_main ();
tcp_connection_t *tc;
tc = pool_elt_at_index (tm->listener_pool, listener_index);
return &tc->connection;
}
/**
* Cleanup half-open connection
*
*/
static void
tcp_half_open_connection_free (tcp_connection_t * tc)
{
tcp_main_t *tm = vnet_get_tcp_main ();
clib_spinlock_lock_if_init (&tm->half_open_lock);
if (CLIB_DEBUG)
clib_memset (tc, 0xFA, sizeof (*tc));
pool_put (tm->half_open_connections, tc);
clib_spinlock_unlock_if_init (&tm->half_open_lock);
}
/**
* Try to cleanup half-open connection
*
* If called from a thread that doesn't own tc, the call won't have any
* effect.
*
* @param tc - connection to be cleaned up
* @return non-zero if cleanup failed.
*/
int
tcp_half_open_connection_cleanup (tcp_connection_t * tc)
{
tcp_worker_ctx_t *wrk;
/* Make sure this is the owning thread */
if (tc->c_thread_index != vlib_get_thread_index ())
return 1;
session_half_open_delete_notify (TRANSPORT_PROTO_TCP, tc->c_s_ho_handle);
wrk = tcp_get_worker (tc->c_thread_index);
tcp_timer_reset (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN);
tcp_half_open_connection_free (tc);
return 0;
}
static tcp_connection_t *
tcp_half_open_connection_new (void)
{
tcp_main_t *tm = vnet_get_tcp_main ();
tcp_connection_t *tc = 0;
ASSERT (vlib_get_thread_index () == 0);
pool_get (tm->half_open_connections, tc);
clib_memset (tc, 0, sizeof (*tc));
tc->c_c_index = tc - tm->half_open_connections;
return tc;
}
/**
* Cleans up connection state.
*
* No notifications.
*/
void
tcp_connection_cleanup (tcp_connection_t * tc)
{
TCP_EVT (TCP_EVT_DELETE, tc);
/* Cleanup local endpoint if this was an active connect */
if (!(tc->cfg_flags & TCP_CFG_F_NO_ENDPOINT))
transport_endpoint_cleanup (TRANSPORT_PROTO_TCP, &tc->c_lcl_ip,
tc->c_lcl_port);
/* Check if connection is not yet fully established */
if (tc->state == TCP_STATE_SYN_SENT)
{
/* Try to remove the half-open connection. If this is not the owning
* thread, tc won't be removed. Retransmit or establish timers will
* eventually expire and call again cleanup on the right thread. */
if (tcp_half_open_connection_cleanup (tc))
tc->flags |= TCP_CONN_HALF_OPEN_DONE;
}
else
{
/* Make sure all timers are cleared */
tcp_connection_timers_reset (tc);
if (!tc->c_is_ip4 && ip6_address_is_link_local_unicast (&tc->c_rmt_ip6))
tcp_add_del_adjacency (tc, 0);
tcp_cc_cleanup (tc);
vec_free (tc->snd_sacks);
vec_free (tc->snd_sacks_fl);
vec_free (tc->rcv_opts.sacks);
pool_free (tc->sack_sb.holes);
if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
tcp_bt_cleanup (tc);
tcp_connection_free (tc);
}
}
/**
* Connection removal.
*
* This should be called only once connection enters CLOSED state. Note
* that it notifies the session of the removal event, so if the goal is to
* just remove the connection, call tcp_connection_cleanup instead.
*/
void
tcp_connection_del (tcp_connection_t * tc)
{
session_transport_delete_notify (&tc->connection);
tcp_connection_cleanup (tc);
}
tcp_connection_t *
tcp_connection_alloc (u8 thread_index)
{
tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
tcp_connection_t *tc;
pool_get (wrk->connections, tc);
clib_memset (tc, 0, sizeof (*tc));
tc->c_c_index = tc - wrk->connections;
tc->c_thread_index = thread_index;
return tc;
}
tcp_connection_t *
tcp_connection_alloc_w_base (u8 thread_index, tcp_connection_t * base)
{
tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
tcp_connection_t *tc;
pool_get (wrk->connections, tc);
clib_memcpy_fast (tc, base, sizeof (*tc));
tc->c_c_index = tc - wrk->connections;
tc->c_thread_index = thread_index;
return tc;
}
void
tcp_connection_free (tcp_connection_t * tc)
{
tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
if (CLIB_DEBUG)
{
clib_memset (tc, 0xFA, sizeof (*tc));
pool_put (wrk->connections, tc);
return;
}
pool_put (wrk->connections, tc);
}
void
tcp_program_cleanup (tcp_worker_ctx_t * wrk, tcp_connection_t * tc)
{
tcp_cleanup_req_t *req;
clib_time_type_t now;
now = tcp_time_now_us (tc->c_thread_index);
clib_fifo_add2 (wrk->pending_cleanups, req);
req->connection_index = tc->c_c_index;
req->free_time = now + tcp_cfg.cleanup_time;
}
/**
* Begin connection closing procedure.
*
* If at the end the connection is not in CLOSED state, it is not removed.
* Instead, we rely on on TCP to advance through state machine to either
* 1) LAST_ACK (passive close) whereby when the last ACK is received
* tcp_connection_del is called. This notifies session of the delete and
* calls cleanup.
* 2) TIME_WAIT (active close) whereby after 2MSL the 2MSL timer triggers
* and cleanup is called.
*
* N.B. Half-close connections are not supported
*/
void
tcp_connection_close (tcp_connection_t * tc)
{
tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
TCP_EVT (TCP_EVT_CLOSE, tc);
/* Send/Program FIN if needed and switch state */
switch (tc->state)
{
case TCP_STATE_SYN_SENT:
/* Try to cleanup. If not on the right thread, mark as half-open done.
* Connection will be cleaned up when establish timer pops */
tcp_connection_cleanup (tc);
break;
case TCP_STATE_SYN_RCVD:
tcp_connection_timers_reset (tc);
tcp_send_fin (tc);
tcp_connection_set_state (tc, TCP_STATE_FIN_WAIT_1);
tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
tcp_cfg.finwait1_time);
break;
case TCP_STATE_ESTABLISHED:
/* If closing with unread data, reset the connection */
if (transport_max_rx_dequeue (&tc->connection))
{
tcp_send_reset (tc);
tcp_connection_timers_reset (tc);
tcp_connection_set_state (tc, TCP_STATE_CLOSED);
session_transport_closed_notify (&tc->connection);
tcp_program_cleanup (tcp_get_worker (tc->c_thread_index), tc);
tcp_worker_stats_inc (wrk, rst_unread, 1);
break;
}
if (!transport_max_tx_dequeue (&tc->connection))
tcp_send_fin (tc);
else
tc->flags |= TCP_CONN_FINPNDG;
tcp_connection_set_state (tc, TCP_STATE_FIN_WAIT_1);
/* Set a timer in case the peer stops responding. Otherwise the
* connection will be stuck here forever. */
ASSERT (tc->timers[TCP_TIMER_WAITCLOSE] == TCP_TIMER_HANDLE_INVALID);
tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
tcp_cfg.finwait1_time);
break;
case TCP_STATE_CLOSE_WAIT:
if (!transport_max_tx_dequeue (&tc->connection))
{
tcp_send_fin (tc);
tcp_connection_timers_reset (tc);
tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
tcp_cfg.lastack_time);
}
else
tc->flags |= TCP_CONN_FINPNDG;
break;
case TCP_STATE_FIN_WAIT_1:
tcp_timer_update (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
tcp_cfg.finwait1_time);
break;
case TCP_STATE_CLOSED:
/* Cleanup should've been programmed already */
break;
default:
TCP_DBG ("state: %u", tc->state);
}
}
static void
tcp_session_close (u32 conn_index, u32 thread_index)
{
tcp_connection_t *tc;
tc = tcp_connection_get (conn_index, thread_index);
tcp_connection_close (tc);
}
static void
tcp_session_cleanup (u32 conn_index, u32 thread_index)
{
tcp_connection_t *tc;
tc = tcp_connection_get (conn_index, thread_index);
if (!tc)
return;
tcp_connection_set_state (tc, TCP_STATE_CLOSED);
tcp_connection_cleanup (tc);
}
static void
tcp_session_cleanup_ho (u32 conn_index)
{
tcp_worker_ctx_t *wrk;
tcp_connection_t *tc;
tc = tcp_half_open_connection_get (conn_index);
wrk = tcp_get_worker (tc->c_thread_index);
tcp_timer_reset (&wrk->timer_wheel, tc, TCP_TIMER_RETRANSMIT_SYN);
tcp_half_open_connection_free (tc);
}
static void
tcp_session_reset (u32 conn_index, u32 thread_index)
{
tcp_connection_t *tc;
tc = tcp_connection_get (conn_index, thread_index);
tcp_send_reset (tc);
tcp_connection_timers_reset (tc);
tcp_cong_recovery_off (tc);
tcp_connection_set_state (tc, TCP_STATE_CLOSED);
session_transport_closed_notify (&tc->connection);
tcp_program_cleanup (tcp_get_worker (thread_index), tc);
}
/**
* Initialize all connection timers as invalid
*/
void
tcp_connection_timers_init (tcp_connection_t * tc)
{
int i;
/* Set all to invalid */
for (i = 0; i < TCP_N_TIMERS; i++)
{
tc->timers[i] = TCP_TIMER_HANDLE_INVALID;
}
tc->rto = TCP_RTO_INIT;
}
/**
* Stop all connection timers
*/
void
tcp_connection_timers_reset (tcp_connection_t * tc)
{
tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
int i;
for (i = 0; i < TCP_N_TIMERS; i++)
tcp_timer_reset (&wrk->timer_wheel, tc, i);
}
#if 0
typedef struct ip4_tcp_hdr
{
ip4_header_t ip;
tcp_header_t tcp;
} ip4_tcp_hdr_t;
typedef struct ip6_tcp_hdr
{
ip6_header_t ip;
tcp_header_t tcp;
} ip6_tcp_hdr_t;
static void
tcp_connection_select_lb_bucket (tcp_connection_t * tc, const dpo_id_t * dpo,
dpo_id_t * result)
{
const dpo_id_t *choice;
load_balance_t *lb;
int hash;
lb = load_balance_get (dpo->dpoi_index);
if (tc->c_is_ip4)
{
ip4_tcp_hdr_t hdr;
clib_memset (&hdr, 0, sizeof (hdr));
hdr.ip.protocol = IP_PROTOCOL_TCP;
hdr.ip.address_pair.src.as_u32 = tc->c_lcl_ip.ip4.as_u32;
hdr.ip.address_pair.dst.as_u32 = tc->c_rmt_ip.ip4.as_u32;
hdr.tcp.src_port = tc->c_lcl_port;
hdr.tcp.dst_port = tc->c_rmt_port;
hash = ip4_compute_flow_hash (&hdr.ip, lb->lb_hash_config);
}
else
{
ip6_tcp_hdr_t hdr;
clib_memset (&hdr, 0, sizeof (hdr));
hdr.ip.protocol = IP_PROTOCOL_TCP;
clib_memcpy_fast (&hdr.ip.src_address, &tc->c_lcl_ip.ip6,
sizeof (ip6_address_t));
clib_memcpy_fast (&hdr.ip.dst_address, &tc->c_rmt_ip.ip6,
sizeof (ip6_address_t));
hdr.tcp.src_port = tc->c_lcl_port;
hdr.tcp.dst_port = tc->c_rmt_port;
hash = ip6_compute_flow_hash (&hdr.ip, lb->lb_hash_config);
}
choice = load_balance_get_bucket_i (lb, hash & lb->lb_n_buckets_minus_1);
dpo_copy (result, choice);
}
fib_node_index_t
tcp_lookup_rmt_in_fib (tcp_connection_t * tc)
{
fib_prefix_t prefix;
u32 fib_index;
clib_memcpy_fast (&prefix.fp_addr, &tc->c_rmt_ip, sizeof (prefix.fp_addr));
prefix.fp_proto = tc->c_is_ip4 ? FIB_PROTOCOL_IP4 : FIB_PROTOCOL_IP6;
prefix.fp_len = tc->c_is_ip4 ? 32 : 128;
fib_index = fib_table_find (prefix.fp_proto, tc->c_fib_index);
return fib_table_lookup (fib_index, &prefix);
}
static int
tcp_connection_stack_on_fib_entry (tcp_connection_t * tc)
{
dpo_id_t choice = DPO_INVALID;
u32 output_node_index;
fib_entry_t *fe;
fe = fib_entry_get (tc->c_rmt_fei);
if (fe->fe_lb.dpoi_type != DPO_LOAD_BALANCE)
return -1;
tcp_connection_select_lb_bucket (tc, &fe->fe_lb, &choice);
output_node_index =
tc->c_is_ip4 ? tcp4_output_node.index : tcp6_output_node.index;
dpo_stack_from_node (output_node_index, &tc->c_rmt_dpo, &choice);
return 0;
}
/** Stack tcp connection on peer's fib entry.
*
* This ultimately populates the dpo the connection will use to send packets.
*/
static void
tcp_connection_fib_attach (tcp_connection_t * tc)
{
tc->c_rmt_fei = tcp_lookup_rmt_in_fib (tc);
ASSERT (tc->c_rmt_fei != FIB_NODE_INDEX_INVALID);
tcp_connection_stack_on_fib_entry (tc);
}
#endif /* 0 */
/**
* Generate random iss as per rfc6528
*/
static u32
tcp_generate_random_iss (tcp_connection_t * tc)
{
tcp_main_t *tm = &tcp_main;
u64 tmp;
if (tc->c_is_ip4)
tmp = (u64) tc->c_lcl_ip.ip4.as_u32 << 32 | (u64) tc->c_rmt_ip.ip4.as_u32;
else
tmp = tc->c_lcl_ip.ip6.as_u64[0] ^ tc->c_lcl_ip.ip6.as_u64[1]
^ tc->c_rmt_ip.ip6.as_u64[0] ^ tc->c_rmt_ip.ip6.as_u64[1];
tmp ^= tm->iss_seed.first | ((u64) tc->c_lcl_port << 16 | tc->c_rmt_port);
tmp ^= tm->iss_seed.second;
tmp = clib_xxhash (tmp) + clib_cpu_time_now ();
return ((tmp >> 32) ^ (tmp & 0xffffffff));
}
/**
* Initialize max segment size we're able to process.
*
* The value is constrained by the output interface's MTU and by the size
* of the IP and TCP headers (see RFC6691). It is also what we advertise
* to our peer.
*/
static void
tcp_init_rcv_mss (tcp_connection_t * tc)
{
u8 ip_hdr_len;
/* Already provided at connection init time */
if (tc->mss)
return;
ip_hdr_len = tc->c_is_ip4 ? sizeof (ip4_header_t) : sizeof (ip6_header_t);
tc->mss = tcp_cfg.default_mtu - sizeof (tcp_header_t) - ip_hdr_len;
}
static void
tcp_init_mss (tcp_connection_t * tc)
{
u16 default_min_mss = 536;
tcp_init_rcv_mss (tc);
/* TODO consider PMTU discovery */
tc->snd_mss = clib_min (tc->rcv_opts.mss, tc->mss);
if (tc->snd_mss < 45)
{
/* Assume that at least the min default mss works */
tc->snd_mss = default_min_mss;
tc->rcv_opts.mss = default_min_mss;
}
/* We should have enough space for 40 bytes of options */
ASSERT (tc->snd_mss > 45);
/* If we use timestamp option, account for it and make sure
* the options are 4-byte aligned */
if (tcp_opts_tstamp (&tc->rcv_opts))
tc->snd_mss -= TCP_OPTION_LEN_TIMESTAMP + 2 /* alignment */;
}
/**
* Initialize connection send variables.
*/
void
tcp_init_snd_vars (tcp_connection_t * tc)
{
/*
* We use the time to randomize iss and for setting up the initial
* timestamp. Make sure it's updated otherwise syn and ack in the
* handshake may make it look as if time has flown in the opposite
* direction for us.
*/
tcp_update_time_now (tcp_get_worker (vlib_get_thread_index ()));
tcp_init_rcv_mss (tc);
tc->iss = tcp_generate_random_iss (tc);
tc->snd_una = tc->iss;
tc->snd_nxt = tc->iss + 1;
tc->srtt = 0.1 * THZ; /* 100 ms */
if (!tcp_cfg.csum_offload)
tc->cfg_flags |= TCP_CFG_F_NO_CSUM_OFFLOAD;
}
void
tcp_enable_pacing (tcp_connection_t * tc)
{
u32 byte_rate;
byte_rate = tc->cwnd / (tc->srtt * TCP_TICK);
transport_connection_tx_pacer_init (&tc->connection, byte_rate, tc->cwnd);
tc->mrtt_us = (u32) ~ 0;
}
/** Initialize tcp connection variables
*
* Should be called after having received a msg from the peer, i.e., a SYN or
* a SYNACK, such that connection options have already been exchanged. */
void
tcp_connection_init_vars (tcp_connection_t * tc)
{
tcp_connection_timers_init (tc);
tcp_init_mss (tc);
scoreboard_init (&tc->sack_sb);
if (tc->state == TCP_STATE_SYN_RCVD)
tcp_init_snd_vars (tc);
tcp_cc_init (tc);
if (!tc->c_is_ip4 && ip6_address_is_link_local_unicast (&tc->c_rmt_ip6))
tcp_add_del_adjacency (tc, 1);
/* tcp_connection_fib_attach (tc); */
if (transport_connection_is_tx_paced (&tc->connection)
|| tcp_cfg.enable_tx_pacing)
tcp_enable_pacing (tc);
if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
tcp_bt_init (tc);
if (!tcp_cfg.allow_tso)
tc->cfg_flags |= TCP_CFG_F_NO_TSO;
tc->start_ts = tcp_time_now_us (tc->c_thread_index);
}
static int
tcp_alloc_custom_local_endpoint (tcp_main_t * tm, ip46_address_t * lcl_addr,
u16 * lcl_port, u8 is_ip4)
{
int index, port;
if (is_ip4)
{
index = tm->last_v4_addr_rotor++;
if (tm->last_v4_addr_rotor >= vec_len (tcp_cfg.ip4_src_addrs))
tm->last_v4_addr_rotor = 0;
lcl_addr->ip4.as_u32 = tcp_cfg.ip4_src_addrs[index].as_u32;
}
else
{
index = tm->last_v6_addr_rotor++;
if (tm->last_v6_addr_rotor >= vec_len (tcp_cfg.ip6_src_addrs))
tm->last_v6_addr_rotor = 0;
clib_memcpy_fast (&lcl_addr->ip6, &tcp_cfg.ip6_src_addrs[index],
sizeof (ip6_address_t));
}
port = transport_alloc_local_port (TRANSPORT_PROTO_TCP, lcl_addr);
if (port < 1)
return SESSION_E_NOPORT;
*lcl_port = port;
return 0;
}
static int
tcp_session_open (transport_endpoint_cfg_t * rmt)
{
tcp_main_t *tm = vnet_get_tcp_main ();
tcp_connection_t *tc;
ip46_address_t lcl_addr;
u16 lcl_port;
int rv;
/*
* Allocate local endpoint
*/
if ((rmt->is_ip4 && vec_len (tcp_cfg.ip4_src_addrs))
|| (!rmt->is_ip4 && vec_len (tcp_cfg.ip6_src_addrs)))
rv = tcp_alloc_custom_local_endpoint (tm, &lcl_addr, &lcl_port,
rmt->is_ip4);
else
rv = transport_alloc_local_endpoint (TRANSPORT_PROTO_TCP,
rmt, &lcl_addr, &lcl_port);
if (rv)
{
if (rv != SESSION_E_PORTINUSE)
return rv;
if (session_lookup_connection (rmt->fib_index, &lcl_addr, &rmt->ip,
lcl_port, rmt->port, TRANSPORT_PROTO_UDP,
rmt->is_ip4))
return SESSION_E_PORTINUSE;
/* 5-tuple is available so increase lcl endpoint refcount and proceed
* with connection allocation */
transport_share_local_endpoint (TRANSPORT_PROTO_UDP, &lcl_addr,
lcl_port);
}
/*
* Create connection and send SYN
*/
clib_spinlock_lock_if_init (&tm->half_open_lock);
tc = tcp_half_open_connection_new ();
ip_copy (&tc->c_rmt_ip, &rmt->ip, rmt->is_ip4);
ip_copy (&tc->c_lcl_ip, &lcl_addr, rmt->is_ip4);
tc->c_rmt_port = rmt->port;
tc->c_lcl_port = clib_host_to_net_u16 (lcl_port);
tc->c_is_ip4 = rmt->is_ip4;
tc->c_proto = TRANSPORT_PROTO_TCP;
tc->c_fib_index = rmt->fib_index;
tc->cc_algo = tcp_cc_algo_get (tcp_cfg.cc_algo);
/* The other connection vars will be initialized after SYN ACK */
tcp_connection_timers_init (tc);
tc->mss = rmt->mss;
TCP_EVT (TCP_EVT_OPEN, tc);
tc->state = TCP_STATE_SYN_SENT;
tcp_init_snd_vars (tc);
tcp_send_syn (tc);
clib_spinlock_unlock_if_init (&tm->half_open_lock);
return tc->c_c_index;
}
static u8 *
format_tcp_session (u8 * s, va_list * args)
{
u32 tci = va_arg (*args, u32);
u32 thread_index = va_arg (*args, u32);
u32 verbose = va_arg (*args, u32);
tcp_connection_t *tc;
tc = tcp_connection_get (tci, thread_index);
if (tc)
s = format (s, "%U", format_tcp_connection, tc, verbose);
else
s = format (s, "empty\n");
return s;
}
static u8 *
format_tcp_listener_session (u8 * s, va_list * args)
{
u32 tci = va_arg (*args, u32);
u32 __clib_unused thread_index = va_arg (*args, u32);
u32 verbose = va_arg (*args, u32);
tcp_connection_t *tc = tcp_listener_get (tci);
s = format (s, "%-" SESSION_CLI_ID_LEN "U", format_tcp_connection_id, tc);
if (verbose)
s = format (s, "%-" SESSION_CLI_STATE_LEN "U", format_tcp_state,
tc->state);
return s;
}
static u8 *
format_tcp_half_open_session (u8 * s, va_list * args)
{
u32 tci = va_arg (*args, u32);
u32 __clib_unused thread_index = va_arg (*args, u32);
tcp_connection_t *tc = tcp_half_open_connection_get (tci);
return format (s, "%U", format_tcp_connection_id, tc);
}
static transport_connection_t *
tcp_session_get_transport (u32 conn_index, u32 thread_index)
{
tcp_connection_t *tc = tcp_connection_get (conn_index, thread_index);
if (PREDICT_FALSE (!tc))
return 0;
return &tc->connection;
}
static transport_connection_t *
tcp_half_open_session_get_transport (u32 conn_index)
{
tcp_connection_t *tc = tcp_half_open_connection_get (conn_index);
return &tc->connection;
}
static int
tcp_set_attribute (tcp_connection_t *tc, transport_endpt_attr_t *attr)
{
int rv = 0;
switch (attr->type)
{
case TRANSPORT_ENDPT_ATTR_NEXT_OUTPUT_NODE:
tc->next_node_index = attr->next_output_node & 0xffffffff;
tc->next_node_opaque = attr->next_output_node >> 32;
break;
case TRANSPORT_ENDPT_ATTR_MSS:
tc->mss = attr->mss;
tc->snd_mss = clib_min (tc->snd_mss, tc->mss);
break;
case TRANSPORT_ENDPT_ATTR_FLAGS:
if (attr->flags & TRANSPORT_ENDPT_ATTR_F_CSUM_OFFLOAD)
tc->cfg_flags |= TCP_CFG_F_NO_CSUM_OFFLOAD;
else
tc->cfg_flags &= ~TCP_CFG_F_NO_CSUM_OFFLOAD;
if (attr->flags & TRANSPORT_ENDPT_ATTR_F_GSO)
{
if (!(tc->cfg_flags & TCP_CFG_F_TSO))
tcp_check_gso (tc);
tc->cfg_flags &= ~TCP_CFG_F_NO_TSO;
}
else
{
tc->cfg_flags |= TCP_CFG_F_NO_TSO;
tc->cfg_flags &= ~TCP_CFG_F_TSO;
}
if (attr->flags & TRANSPORT_ENDPT_ATTR_F_RATE_SAMPLING)
{
if (!(tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE))
tcp_bt_init (tc);
tc->cfg_flags |= TCP_CFG_F_RATE_SAMPLE;
}
else
{
if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
tcp_bt_cleanup (tc);
tc->cfg_flags &= ~TCP_CFG_F_RATE_SAMPLE;
}
break;
case TRANSPORT_ENDPT_ATTR_CC_ALGO:
if (tc->cc_algo == tcp_cc_algo_get (attr->cc_algo))
break;
tcp_cc_cleanup (tc);
tc->cc_algo = tcp_cc_algo_get (attr->cc_algo);
tcp_cc_init (tc);
break;
default:
rv = -1;
break;
}
return rv;
}
static int
tcp_get_attribute (tcp_connection_t *tc, transport_endpt_attr_t *attr)
{
int rv = 0;
u64 non;
switch (attr->type)
{
case TRANSPORT_ENDPT_ATTR_NEXT_OUTPUT_NODE:
non = (u64) tc->next_node_opaque << 32 | tc->next_node_index;
attr->next_output_node = non;
break;
case TRANSPORT_ENDPT_ATTR_MSS:
attr->mss = tc->snd_mss;
break;
case TRANSPORT_ENDPT_ATTR_FLAGS:
attr->flags = 0;
if (!(tc->cfg_flags & TCP_CFG_F_NO_CSUM_OFFLOAD))
attr->flags |= TRANSPORT_ENDPT_ATTR_F_CSUM_OFFLOAD;
if (tc->cfg_flags & TCP_CFG_F_TSO)
attr->flags |= TRANSPORT_ENDPT_ATTR_F_GSO;
if (tc->cfg_flags & TCP_CFG_F_RATE_SAMPLE)
attr->flags |= TRANSPORT_ENDPT_ATTR_F_RATE_SAMPLING;
break;
case TRANSPORT_ENDPT_ATTR_CC_ALGO:
attr->cc_algo = tc->cc_algo - tcp_main.cc_algos;
break;
default:
rv = -1;
break;
}
return rv;
}
static int
tcp_session_attribute (u32 conn_index, u32 thread_index, u8 is_get,
transport_endpt_attr_t *attr)
{
tcp_connection_t *tc = tcp_connection_get (conn_index, thread_index);
if (PREDICT_FALSE (!tc))
return -1;
if (is_get)
return tcp_get_attribute (tc, attr);
else
return tcp_set_attribute (tc, attr);
}
static u16
tcp_session_cal_goal_size (tcp_connection_t * tc)
{
u16 goal_size = tc->snd_mss;
goal_size = tcp_cfg.max_gso_size - tc->snd_mss % tcp_cfg.max_gso_size;
goal_size = clib_min (goal_size, tc->snd_wnd / 2);
return goal_size > tc->snd_mss ? goal_size : tc->snd_mss;
}
always_inline u32
tcp_round_snd_space (tcp_connection_t * tc, u32 snd_space)
{
if (PREDICT_FALSE (tc->snd_wnd < tc->snd_mss))
{
return tc->snd_wnd <= snd_space ? tc->snd_wnd : 0;
}
/* If not snd_wnd constrained and we can't write at least a segment,
* don't try at all */
if (PREDICT_FALSE (snd_space < tc->snd_mss))
return snd_space < tc->cwnd ? 0 : snd_space;
/* round down to mss multiple */
return snd_space - (snd_space % tc->snd_mss);
}
/**
* Compute tx window session is allowed to fill.
*
* Takes into account available send space, snd_mss and the congestion
* state of the connection. If possible, the value returned is a multiple
* of snd_mss.
*
* @param tc tcp connection
* @return number of bytes session is allowed to write
*/
static inline u32
tcp_snd_space_inline (tcp_connection_t * tc)
{
int snd_space;
/* Fast path is disabled when recovery is on. @ref tcp_session_custom_tx
* controls both retransmits and the sending of new data while congested
*/
if (PREDICT_FALSE (tcp_in_cong_recovery (tc)
|| tc->state == TCP_STATE_CLOSED))
return 0;
snd_space = tcp_available_output_snd_space (tc);
/* If we got dupacks or sacked bytes but we're not yet in recovery, try
* to force the peer to send enough dupacks to start retransmitting as
* per Limited Transmit (RFC3042)
*/
if (PREDICT_FALSE (tc->rcv_dupacks || tc->sack_sb.sacked_bytes))
{
int snt_limited, n_pkts;
n_pkts = tcp_opts_sack_permitted (&tc->rcv_opts)
? tc->sack_sb.reorder - 1 : 2;
if ((seq_lt (tc->limited_transmit, tc->snd_nxt - n_pkts * tc->snd_mss)
|| seq_gt (tc->limited_transmit, tc->snd_nxt)))
tc->limited_transmit = tc->snd_nxt;
ASSERT (seq_leq (tc->limited_transmit, tc->snd_nxt));
snt_limited = tc->snd_nxt - tc->limited_transmit;
snd_space = clib_max (n_pkts * tc->snd_mss - snt_limited, 0);
}
return tcp_round_snd_space (tc, snd_space);
}
u32
tcp_snd_space (tcp_connection_t * tc)
{
return tcp_snd_space_inline (tc);
}
static int
tcp_session_send_params (transport_connection_t * trans_conn,
transport_send_params_t * sp)
{
tcp_connection_t *tc = (tcp_connection_t *) trans_conn;
/* Ensure snd_mss does accurately reflect the amount of data we can push
* in a segment. This also makes sure that options are updated according to
* the current state of the connection. */
tcp_update_burst_snd_vars (tc);
if (PREDICT_FALSE (tc->cfg_flags & TCP_CFG_F_TSO))
sp->snd_mss = tcp_session_cal_goal_size (tc);
else
sp->snd_mss = tc->snd_mss;
sp->snd_space = clib_min (tcp_snd_space_inline (tc),
tc->snd_wnd - (tc->snd_nxt - tc->snd_una));
ASSERT (seq_geq (tc->snd_nxt, tc->snd_una));
/* This still works if fast retransmit is on */
sp->tx_offset = tc->snd_nxt - tc->snd_una;
sp->flags = sp->snd_space ? 0 : TRANSPORT_SND_F_DESCHED;
return 0;
}
static void
tcp_timer_waitclose_handler (tcp_connection_t * tc)
{
tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
switch (tc->state)
{
case TCP_STATE_CLOSE_WAIT:
tcp_connection_timers_reset (tc);
/* App never returned with a close */
if (!(tc->flags & TCP_CONN_FINPNDG))
{
tcp_connection_set_state (tc, TCP_STATE_CLOSED);
session_transport_closed_notify (&tc->connection);
tcp_program_cleanup (wrk, tc);
tcp_worker_stats_inc (wrk, to_closewait, 1);
break;
}
/* Send FIN either way and switch to LAST_ACK. */
tcp_cong_recovery_off (tc);
/* Make sure we don't try to send unsent data */
tc->snd_nxt = tc->snd_una;
tcp_send_fin (tc);
tcp_connection_set_state (tc, TCP_STATE_LAST_ACK);
session_transport_closed_notify (&tc->connection);
/* Make sure we don't wait in LAST ACK forever */
tcp_timer_set (&wrk->timer_wheel, tc, TCP_TIMER_WAITCLOSE,
tcp_cfg.lastack_time);
tcp_worker_stats_inc (wrk, to_closewait2, 1);
/* Don't delete the connection yet */
break;
case TCP_STATE_FIN_WAIT_1:
tcp_connection_timers_reset (tc);
if (tc->flags & TCP_CONN_FINPNDG)
{
/* If FIN pending, we haven't sent everything, but we did try.
* Notify session layer that transport is closed. */
tcp_connection_set_state (tc, TCP_STATE_CLOSED);
tcp_send_reset (tc);
tcp_program_cleanup (wrk, tc);
}
else
{
/* We've sent the fin but no progress. Close the connection and
* to make sure everything is flushed, setup a cleanup timer */
tcp_connection_set_state (tc, TCP_STATE_CLOSED);
tcp_program_cleanup (wrk, tc);
}
session_transport_closed_notify (&tc->connection);
tcp_worker_stats_inc (wrk, to_finwait1, 1);
break;
case TCP_STATE_LAST_ACK:
tcp_connection_timers_reset (tc);
tcp_connection_set_state (tc, TCP_STATE_CLOSED);
session_transport_closed_notify (&tc->connection);
tcp_program_cleanup (wrk, tc);
tcp_worker_stats_inc (wrk, to_lastack, 1);
break;
case TCP_STATE_CLOSING:
tcp_connection_timers_reset (tc);
tcp_connection_set_state (tc, TCP_STATE_CLOSED);
session_transport_closed_notify (&tc->connection);
tcp_program_cleanup (wrk, tc);
tcp_worker_stats_inc (wrk, to_closing, 1);
break;
case TCP_STATE_FIN_WAIT_2:
tcp_send_reset (tc);
tcp_connection_timers_reset (tc);
tcp_connection_set_state (tc, TCP_STATE_CLOSED);
session_transport_closed_notify (&tc->connection);
tcp_program_cleanup (wrk, tc);
tcp_worker_stats_inc (wrk, to_finwait2, 1);
break;
case TCP_STATE_TIME_WAIT:
tcp_connection_set_state (tc, TCP_STATE_CLOSED);
tcp_program_cleanup (wrk, tc);
break;
default:
clib_warning ("waitclose in state: %U", format_tcp_state, tc->state);
break;
}
}
/* *INDENT-OFF* */
static timer_expiration_handler *timer_expiration_handlers[TCP_N_TIMERS] =
{
tcp_timer_retransmit_handler,
tcp_timer_persist_handler,
tcp_timer_waitclose_handler,
tcp_timer_retransmit_syn_handler,
};
/* *INDENT-ON* */
static void
tcp_dispatch_pending_timers (tcp_worker_ctx_t * wrk)
{
u32 n_timers, connection_index, timer_id, thread_index, timer_handle;
tcp_connection_t *tc;
int i;
if (!(n_timers = clib_fifo_elts (wrk->pending_timers)))
return;
thread_index = wrk->vm->thread_index;
for (i = 0; i < clib_min (n_timers, wrk->max_timers_per_loop); i++)
{
clib_fifo_sub1 (wrk->pending_timers, timer_handle);
connection_index = timer_handle & 0x0FFFFFFF;
timer_id = timer_handle >> 28;
if (PREDICT_TRUE (timer_id != TCP_TIMER_RETRANSMIT_SYN))
tc = tcp_connection_get (connection_index, thread_index);
else
tc = tcp_half_open_connection_get (connection_index);
if (PREDICT_FALSE (!tc))
continue;
/* Skip if the timer is not pending. Probably it was reset while
* waiting for dispatch */
if (PREDICT_FALSE (!(tc->pending_timers & (1 << timer_id))))
continue;
tc->pending_timers &= ~(1 << timer_id);
/* Skip timer if it was rearmed while pending dispatch */
if (PREDICT_FALSE (tc->timers[timer_id] != TCP_TIMER_HANDLE_INVALID))
continue;
(*timer_expiration_handlers[timer_id]) (tc);
}
if (thread_index == 0 && clib_fifo_elts (wrk->pending_timers))
session_queue_run_on_main_thread (wrk->vm);
}
static void
tcp_handle_cleanups (tcp_worker_ctx_t * wrk, clib_time_type_t now)
{
u32 thread_index = wrk->vm->thread_index;
tcp_cleanup_req_t *req;
tcp_connection_t *tc;
while (clib_fifo_elts (wrk->pending_cleanups))
{
req = clib_fifo_head (wrk->pending_cleanups);
if (req->free_time > now)
break;
clib_fifo_sub2 (wrk->pending_cleanups, req);
tc = tcp_connection_get (req->connection_index, thread_index);
if (PREDICT_FALSE (!tc))
continue;
session_transport_delete_notify (&tc->connection);
tcp_connection_cleanup (tc);
}
}
static void
tcp_update_time (f64 now, u8 thread_index)
{
tcp_worker_ctx_t *wrk = tcp_get_worker (thread_index);
tcp_set_time_now (wrk, now);
tcp_handle_cleanups (wrk, now);
tcp_timer_expire_timers (&wrk->timer_wheel, now);
tcp_dispatch_pending_timers (wrk);
}
static void
tcp_session_flush_data (transport_connection_t * tconn)
{
tcp_connection_t *tc = (tcp_connection_t *) tconn;
if (tc->flags & TCP_CONN_PSH_PENDING)
return;
tc->flags |= TCP_CONN_PSH_PENDING;
tc->psh_seq = tc->snd_una + transport_max_tx_dequeue (tconn) - 1;
}
static int
tcp_session_app_rx_evt (transport_connection_t *conn)
{
tcp_connection_t *tc = (tcp_connection_t *) conn;
u32 min_free, lo = 4 << 10, hi = 128 << 10;
if (!(tc->flags & TCP_CONN_ZERO_RWND_SENT))
return 0;
min_free = clib_clamp (transport_rx_fifo_size (conn) >> 3, lo, hi);
if (transport_max_rx_enqueue (conn) < min_free)
{
transport_rx_fifo_req_deq_ntf (conn);
return 0;
}
tcp_send_ack (tc);
return 0;
}
/* *INDENT-OFF* */
const static transport_proto_vft_t tcp_proto = {
.enable = vnet_tcp_enable_disable,
.start_listen = tcp_session_bind,
.stop_listen = tcp_session_unbind,
.push_header = tcp_session_push_header,
.get_connection = tcp_session_get_transport,
.get_listener = tcp_session_get_listener,
.get_half_open = tcp_half_open_session_get_transport,
.attribute = tcp_session_attribute,
.connect = tcp_session_open,
.close = tcp_session_close,
.cleanup = tcp_session_cleanup,
.cleanup_ho = tcp_session_cleanup_ho,
.reset = tcp_session_reset,
.send_params = tcp_session_send_params,
.update_time = tcp_update_time,
.flush_data = tcp_session_flush_data,
.custom_tx = tcp_session_custom_tx,
.app_rx_evt = tcp_session_app_rx_evt,
.format_connection = format_tcp_session,
.format_listener = format_tcp_listener_session,
.format_half_open = format_tcp_half_open_session,
.transport_options = {
.name = "tcp",
.short_name = "T",
.tx_type = TRANSPORT_TX_PEEK,
.service_type = TRANSPORT_SERVICE_VC,
},
};
/* *INDENT-ON* */
void
tcp_connection_tx_pacer_update (tcp_connection_t * tc)
{
if (!transport_connection_is_tx_paced (&tc->connection))
return;
f64 srtt = clib_min ((f64) tc->srtt * TCP_TICK, tc->mrtt_us);
transport_connection_tx_pacer_update (&tc->connection,
tcp_cc_get_pacing_rate (tc),
srtt * CLIB_US_TIME_FREQ);
}
void
tcp_connection_tx_pacer_reset (tcp_connection_t * tc, u32 window,
u32 start_bucket)
{
f64 srtt = clib_min ((f64) tc->srtt * TCP_TICK, tc->mrtt_us);
transport_connection_tx_pacer_reset (&tc->connection,
tcp_cc_get_pacing_rate (tc),
start_bucket,
srtt * CLIB_US_TIME_FREQ);
}
void
tcp_reschedule (tcp_connection_t * tc)
{
if (tcp_in_cong_recovery (tc) || tcp_snd_space_inline (tc))
transport_connection_reschedule (&tc->connection);
}
static void
tcp_expired_timers_dispatch (u32 * expired_timers)
{
u32 thread_index = vlib_get_thread_index (), n_left, max_per_loop;
u32 connection_index, timer_id, n_expired, max_loops;
tcp_worker_ctx_t *wrk;
tcp_connection_t *tc;
int i;
wrk = tcp_get_worker (thread_index);
n_expired = vec_len (expired_timers);
tcp_worker_stats_inc (wrk, timer_expirations, n_expired);
n_left = clib_fifo_elts (wrk->pending_timers);
/*
* Invalidate all timer handles before dispatching. This avoids dangling
* index references to timer wheel pool entries that have been freed.
*/
for (i = 0; i < n_expired; i++)
{
connection_index = expired_timers[i] & 0x0FFFFFFF;
timer_id = expired_timers[i] >> 28;
if (timer_id != TCP_TIMER_RETRANSMIT_SYN)
tc = tcp_connection_get (connection_index, thread_index);
else
tc = tcp_half_open_connection_get (connection_index);
TCP_EVT (TCP_EVT_TIMER_POP, connection_index, timer_id);
tc->timers[timer_id] = TCP_TIMER_HANDLE_INVALID;
tc->pending_timers |= (1 << timer_id);
}
clib_fifo_add (wrk->pending_timers, expired_timers, n_expired);
max_loops = clib_max (1, 0.5 * TCP_TIMER_TICK * wrk->vm->loops_per_second);
max_per_loop = clib_max ((n_left + n_expired) / max_loops, 10);
max_per_loop = clib_min (max_per_loop, VLIB_FRAME_SIZE);
wrk->max_timers_per_loop = clib_max (n_left ? wrk->max_timers_per_loop : 0,
max_per_loop);
if (thread_index == 0)
session_queue_run_on_main_thread (wrk->vm);
}
static void
tcp_initialize_iss_seed (tcp_main_t * tm)
{
u32 default_seed = random_default_seed ();
u64 time_now = clib_cpu_time_now ();
tm->iss_seed.first = (u64) random_u32 (&default_seed) << 32;
tm->iss_seed.second = random_u64 (&time_now);
}
static clib_error_t *
tcp_main_enable (vlib_main_t * vm)
{
vlib_thread_main_t *vtm = vlib_get_thread_main ();
u32 num_threads, n_workers, prealloc_conn_per_wrk;
tcp_connection_t *tc __attribute__ ((unused));
tcp_main_t *tm = vnet_get_tcp_main ();
tcp_worker_ctx_t *wrk;
clib_error_t *error = 0;
int thread;
if ((error = vlib_call_init_function (vm, ip_main_init)))
return error;
if ((error = vlib_call_init_function (vm, ip4_lookup_init)))
return error;
if ((error = vlib_call_init_function (vm, ip6_lookup_init)))
return error;
/*
* Registrations
*/
ip4_register_protocol (IP_PROTOCOL_TCP, tcp4_input_node.index);
ip6_register_protocol (IP_PROTOCOL_TCP, tcp6_input_node.index);
/*
* Initialize data structures
*/
num_threads = 1 /* main thread */ + vtm->n_threads;
vec_validate (tm->wrk_ctx, num_threads - 1);
n_workers = num_threads == 1 ? 1 : vtm->n_threads;
prealloc_conn_per_wrk = tcp_cfg.preallocated_connections / n_workers;
wrk = &tm->wrk_ctx[0];
wrk->tco_next_node[0] = vlib_node_get_next (vm, session_queue_node.index,
tcp4_output_node.index);
wrk->tco_next_node[1] = vlib_node_get_next (vm, session_queue_node.index,
tcp6_output_node.index);
for (thread = 0; thread < num_threads; thread++)
{
wrk = &tm->wrk_ctx[thread];
vec_validate (wrk->pending_deq_acked, 255);
vec_validate (wrk->pending_disconnects, 255);
vec_validate (wrk->pending_resets, 255);
vec_reset_length (wrk->pending_deq_acked);
vec_reset_length (wrk->pending_disconnects);
vec_reset_length (wrk->pending_resets);
wrk->vm = vlib_get_main_by_index (thread);
wrk->max_timers_per_loop = 10;
if (thread > 0)
{
wrk->tco_next_node[0] = tm->wrk_ctx[0].tco_next_node[0];
wrk->tco_next_node[1] = tm->wrk_ctx[0].tco_next_node[1];
}
/*
* Preallocate connections. Assume that thread 0 won't
* use preallocated threads when running multi-core
*/
if ((thread > 0 || num_threads == 1) && prealloc_conn_per_wrk)
pool_init_fixed (wrk->connections, prealloc_conn_per_wrk);
tcp_timer_initialize_wheel (&wrk->timer_wheel,
tcp_expired_timers_dispatch,
vlib_time_now (vm));
}
/*
* Use a preallocated half-open connection pool?
*/
if (tcp_cfg.preallocated_half_open_connections)
pool_init_fixed (tm->half_open_connections,
tcp_cfg.preallocated_half_open_connections);
if (num_threads > 1)
{
clib_spinlock_init (&tm->half_open_lock);
}
tcp_initialize_iss_seed (tm);
tm->bytes_per_buffer = vlib_buffer_get_default_data_size (vm);
tm->cc_last_type = TCP_CC_LAST;
tm->ipl_next_node[0] = vlib_node_get_next (vm, session_queue_node.index,
ip4_lookup_node.index);
tm->ipl_next_node[1] = vlib_node_get_next (vm, session_queue_node.index,
ip6_lookup_node.index);
return error;
}
clib_error_t *
vnet_tcp_enable_disable (vlib_main_t * vm, u8 is_en)
{
if (is_en)
{
if (tcp_main.is_enabled)
return 0;
return tcp_main_enable (vm);
}
else
{
tcp_main.is_enabled = 0;
}
return 0;
}
void
tcp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add)
{
tcp_main_t *tm = &tcp_main;
if (is_ip4)
tm->punt_unknown4 = is_add;
else
tm->punt_unknown6 = is_add;
}
/**
* Initialize default values for tcp parameters
*/
static void
tcp_configuration_init (void)
{
/* Initial wnd for SYN. Fifos are not allocated at that point so use some
* predefined value. For SYN-ACK we still want the scale to be computed in
* the same way */
tcp_cfg.max_rx_fifo = 32 << 20;
tcp_cfg.min_rx_fifo = 4 << 10;
tcp_cfg.default_mtu = 1500;
tcp_cfg.initial_cwnd_multiplier = 0;
tcp_cfg.enable_tx_pacing = 1;
tcp_cfg.allow_tso = 0;
tcp_cfg.csum_offload = 1;
tcp_cfg.cc_algo = TCP_CC_CUBIC;
tcp_cfg.rwnd_min_update_ack = 1;
tcp_cfg.max_gso_size = TCP_MAX_GSO_SZ;
/* Time constants defined as timer tick (100us) multiples */
tcp_cfg.closewait_time = 20000; /* 2s */
tcp_cfg.timewait_time = 100000; /* 10s */
tcp_cfg.finwait1_time = 600000; /* 60s */
tcp_cfg.lastack_time = 300000; /* 30s */
tcp_cfg.finwait2_time = 300000; /* 30s */
tcp_cfg.closing_time = 300000; /* 30s */
/* This value is seconds */
tcp_cfg.cleanup_time = 0.1; /* 100ms */
}
static clib_error_t *
tcp_init (vlib_main_t * vm)
{
tcp_main_t *tm = vnet_get_tcp_main ();
ip_main_t *im = &ip_main;
ip_protocol_info_t *pi;
/* Session layer, and by implication tcp, are disabled by default */
tm->is_enabled = 0;
/* Register with IP for header parsing */
pi = ip_get_protocol_info (im, IP_PROTOCOL_TCP);
if (pi == 0)
return clib_error_return (0, "TCP protocol info AWOL");
pi->format_header = format_tcp_header;
pi->unformat_pg_edit = unformat_pg_tcp_header;
/* Register as transport with session layer */
transport_register_protocol (TRANSPORT_PROTO_TCP, &tcp_proto,
FIB_PROTOCOL_IP4, tcp4_output_node.index);
transport_register_protocol (TRANSPORT_PROTO_TCP, &tcp_proto,
FIB_PROTOCOL_IP6, tcp6_output_node.index);
tcp_configuration_init ();
tm->cc_algo_by_name = hash_create_string (0, sizeof (uword));
return 0;
}
VLIB_INIT_FUNCTION (tcp_init);
/*
* fd.io coding-style-patch-verification: ON
*
* Local Variables:
* eval: (c-set-style "gnu")
* End:
*/
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