tcp.h File Reference

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Data Structures
struct	tcp_worker_ctx_

Macros
#define	TCP_TICK   0.001
	TCP tick period (s) More...
#define	THZ   (u32) (1/TCP_TICK)
	TCP tick frequency. More...
#define	TCP_TSTAMP_RESOLUTION   TCP_TICK
	Time stamp resolution. More...
#define	TCP_PAWS_IDLE   24 * 24 * 60 * 60 * THZ
	24 days More...
#define	TCP_FIB_RECHECK_PERIOD   1 * THZ
	Recheck every 1s. More...
#define	TCP_MAX_OPTION_SPACE   40
#define	TCP_DUPACK_THRESHOLD   3
#define	TCP_MAX_RX_FIFO_SIZE   4 << 20
#define	TCP_MIN_RX_FIFO_SIZE   4 << 10
#define	TCP_IW_N_SEGMENTS   10
#define	TCP_ALWAYS_ACK   1
	On/off delayed acks. More...
#define	TCP_USE_SACKS   1
	Disable only for testing. More...
#define	foreach_tcp_fsm_state
	TCP FSM state definitions as per RFC793. More...
#define	foreach_tcp_timer
	TCP timers. More...
#define	TCP_TIMER_HANDLE_INVALID   ((u32) ~0)
#define	TCP_TO_TIMER_TICK
#define	TCP_DELACK_TIME   1 /* 0.1s */
#define	TCP_ESTABLISH_TIME   750 /* 75s */
#define	TCP_SYN_RCVD_TIME   600 /* 60s */
#define	TCP_2MSL_TIME   300 /* 30s */
#define	TCP_CLOSEWAIT_TIME   20 /* 2s */
#define	TCP_TIMEWAIT_TIME   100 /* 10s */
#define	TCP_CLEANUP_TIME   10 /* 1s Time to wait before cleanup */
#define	TCP_TIMER_PERSIST_MIN   2 /* 0.2s */
#define	TCP_RTO_MAX   60 * THZ /* Min max RTO (60s) as per RFC6298 */
#define	TCP_RTO_MIN   0.2 * THZ /* Min RTO (200ms) - lower than standard */
#define	TCP_RTT_MAX   30 * THZ /* 30s (probably too much) */
#define	TCP_RTO_SYN_RETRIES   3 /* SYN retries without doubling RTO */
#define	TCP_RTO_INIT   1 * THZ /* Initial retransmit timer */
#define	foreach_tcp_connection_flag
	TCP connection flags. More...
#define	foreach_tcp_buf_flag
	TCP buffer flags. More...
#define	TCP_SCOREBOARD_TRACE   (0)
#define	TCP_MAX_SACK_BLOCKS   15
	Max number of SACK blocks stored. More...
#define	TCP_INVALID_SACK_HOLE_INDEX   ((u32)~0)
#define	tcp_scoreboard_trace_add(_tc, _ack)
#define	tcp_fastrecovery_on(tc)   (tc)->flags |= TCP_CONN_FAST_RECOVERY
#define	tcp_fastrecovery_off(tc)   (tc)->flags &= ~TCP_CONN_FAST_RECOVERY
#define	tcp_recovery_on(tc)   (tc)->flags |= TCP_CONN_RECOVERY
#define	tcp_recovery_off(tc)   (tc)->flags &= ~TCP_CONN_RECOVERY
#define	tcp_in_fastrecovery(tc)   ((tc)->flags & TCP_CONN_FAST_RECOVERY)
#define	tcp_in_recovery(tc)   ((tc)->flags & (TCP_CONN_RECOVERY))
#define	tcp_in_slowstart(tc)   (tc->cwnd < tc->ssthresh)
#define	tcp_fastrecovery_sent_1_smss(tc)   ((tc)->flags & TCP_CONN_FR_1_SMSS)
#define	tcp_fastrecovery_1_smss_on(tc)   ((tc)->flags |= TCP_CONN_FR_1_SMSS)
#define	tcp_fastrecovery_1_smss_off(tc)   ((tc)->flags &= ~TCP_CONN_FR_1_SMSS)
#define	tcp_in_cong_recovery(tc)
#define	tcp_error(n, s)   TCP_ERROR_##n,
#define	tcp_trajectory_add_start(b, start)
#define	seq_lt(_s1, _s2)   ((i32)((_s1)-(_s2)) < 0)
#define	seq_leq(_s1, _s2)   ((i32)((_s1)-(_s2)) <= 0)
#define	seq_gt(_s1, _s2)   ((i32)((_s1)-(_s2)) > 0)
#define	seq_geq(_s1, _s2)   ((i32)((_s1)-(_s2)) >= 0)
#define	seq_max(_s1, _s2)   (seq_gt((_s1), (_s2)) ? (_s1) : (_s2))
#define	timestamp_lt(_t1, _t2)   ((i32)((_t1)-(_t2)) < 0)
#define	timestamp_leq(_t1, _t2)   ((i32)((_t1)-(_t2)) <= 0)
#define	tcp_validate_txf_size(_tc, _a)

Typedefs
typedef enum _tcp_state	tcp_state_t
typedef enum _tcp_timers	tcp_timers_e
typedef void(	timer_expiration_handler) (u32 index)
typedef enum _tcp_connection_flag_bits	tcp_connection_flag_bits_e
typedef enum _tcp_connection_flag	tcp_connection_flags_e
typedef struct _scoreboard_trace_elt	scoreboard_trace_elt_t
typedef struct _sack_scoreboard_hole	sack_scoreboard_hole_t
typedef struct _sack_scoreboard	sack_scoreboard_t
typedef enum _tcp_cc_algorithm_type	tcp_cc_algorithm_type_e
typedef struct _tcp_cc_algorithm	tcp_cc_algorithm_t
typedef enum _tcp_cc_ack_t	tcp_cc_ack_t
typedef struct _tcp_connection	tcp_connection_t
typedef enum _tcp_error	tcp_error_t
typedef struct _tcp_lookup_dispatch	tcp_lookup_dispatch_t
typedef struct tcp_worker_ctx_	tcp_worker_ctx_t
typedef struct _tcp_main	tcp_main_t

Enumerations
enum	{ TCP_N_BUF_BITS }
enum	{ foreach_tcp_buf_flag }

Functions
sack_scoreboard_hole_t *	scoreboard_next_rxt_hole (sack_scoreboard_t *sb, sack_scoreboard_hole_t *start, u8 have_sent_1_smss, u8 *can_rescue, u8 *snd_limited)
	Figure out the next hole to retransmit. More...
sack_scoreboard_hole_t *	scoreboard_get_hole (sack_scoreboard_t *sb, u32 index)
sack_scoreboard_hole_t *	scoreboard_next_hole (sack_scoreboard_t *sb, sack_scoreboard_hole_t *hole)
sack_scoreboard_hole_t *	scoreboard_prev_hole (sack_scoreboard_t *sb, sack_scoreboard_hole_t *hole)
sack_scoreboard_hole_t *	scoreboard_first_hole (sack_scoreboard_t *sb)
sack_scoreboard_hole_t *	scoreboard_last_hole (sack_scoreboard_t *sb)
void	scoreboard_clear (sack_scoreboard_t *sb)
void	scoreboard_init (sack_scoreboard_t *sb)
u8 *	format_tcp_scoreboard (u8 *s, va_list *args)
static void	tcp_cong_recovery_off (tcp_connection_t *tc)
static tcp_main_t *	vnet_get_tcp_main ()
static tcp_header_t *	tcp_buffer_hdr (vlib_buffer_t *b)
clib_error_t *	vnet_tcp_enable_disable (vlib_main_t *vm, u8 is_en)
void	tcp_punt_unknown (vlib_main_t *vm, u8 is_ip4, u8 is_add)
static tcp_connection_t *	tcp_connection_get (u32 conn_index, u32 thread_index)
static tcp_connection_t *	tcp_connection_get_if_valid (u32 conn_index, u32 thread_index)
static tcp_connection_t *	tcp_get_connection_from_transport (transport_connection_t *tconn)
void	tcp_connection_close (tcp_connection_t *tc)
	Begin connection closing procedure. More...
void	tcp_connection_cleanup (tcp_connection_t *tc)
	Cleans up connection state. More...
void	tcp_connection_del (tcp_connection_t *tc)
	Connection removal. More...
int	tcp_half_open_connection_cleanup (tcp_connection_t *tc)
	Try to cleanup half-open connection. More...
tcp_connection_t *	tcp_connection_new (u8 thread_index)
void	tcp_connection_reset (tcp_connection_t *tc)
	Notify session that connection has been reset. More...
int	tcp_configure_v4_source_address_range (vlib_main_t *vm, ip4_address_t *start, ip4_address_t *end, u32 table_id)
	Configure an ipv4 source address range. More...
int	tcp_configure_v6_source_address_range (vlib_main_t *vm, ip6_address_t *start, ip6_address_t *end, u32 table_id)
	Configure an ipv6 source address range. More...
void	tcp_api_reference (void)
u8 *	format_tcp_connection (u8 *s, va_list *args)
static tcp_connection_t *	tcp_listener_get (u32 tli)
static tcp_connection_t *	tcp_half_open_connection_get (u32 conn_index)
void	tcp_make_ack (tcp_connection_t *ts, vlib_buffer_t *b)
	Convert buffer to ACK. More...
void	tcp_make_fin (tcp_connection_t *tc, vlib_buffer_t *b)
	Convert buffer to FIN-ACK. More...
void	tcp_make_synack (tcp_connection_t *ts, vlib_buffer_t *b)
	Convert buffer to SYN-ACK. More...
void	tcp_send_reset_w_pkt (tcp_connection_t *tc, vlib_buffer_t *pkt, u8 is_ip4)
	Send reset without reusing existing buffer. More...
void	tcp_send_reset (tcp_connection_t *tc)
	Build and set reset packet for connection. More...
void	tcp_send_syn (tcp_connection_t *tc)
	Send SYN. More...
void	tcp_send_fin (tcp_connection_t *tc)
	Send FIN. More...
void	tcp_init_mss (tcp_connection_t *tc)
void	tcp_update_burst_snd_vars (tcp_connection_t *tc)
	Update burst send vars. More...
void	tcp_update_rto (tcp_connection_t *tc)
void	tcp_flush_frame_to_output (vlib_main_t *vm, u8 thread_index, u8 is_ip4)
	Flush tx frame populated by retransmits and timer pops. More...
void	tcp_flush_frames_to_output (u8 thread_index)
	Flush v4 and v6 tcp and ip-lookup tx frames for thread index. More...
static u32	tcp_end_seq (tcp_header_t *th, u32 len)
static u32	tcp_bytes_out (const tcp_connection_t *tc)
	Our estimate of the number of bytes that have left the network. More...
static u32	tcp_flight_size (const tcp_connection_t *tc)
	Our estimate of the number of bytes in flight (pipe size) More...
static u32	tcp_initial_cwnd (const tcp_connection_t *tc)
	Initial cwnd as per RFC5681. More...
static u32	tcp_loss_wnd (const tcp_connection_t *tc)
static u32	tcp_available_snd_wnd (const tcp_connection_t *tc)
static u32	tcp_available_output_snd_space (const tcp_connection_t *tc)
static u32	tcp_available_cc_snd_space (const tcp_connection_t *tc)
	Estimate of how many bytes we can still push into the network. More...
static u8	tcp_is_lost_fin (tcp_connection_t *tc)
void	tcp_retransmit_first_unacked (tcp_connection_t *tc)
	Retransmit first unacked segment. More...
void	tcp_fast_retransmit_no_sack (tcp_connection_t *tc)
	Fast retransmit without SACK info. More...
void	tcp_fast_retransmit_sack (tcp_connection_t *tc)
	Do fast retransmit with SACKs. More...
void	tcp_fast_retransmit (tcp_connection_t *tc)
	Do fast retransmit. More...
void	tcp_cc_init_congestion (tcp_connection_t *tc)
	Init loss recovery/fast recovery. More...
void	tcp_cc_fastrecovery_exit (tcp_connection_t *tc)
fib_node_index_t	tcp_lookup_rmt_in_fib (tcp_connection_t *tc)
void	tcp_update_sack_list (tcp_connection_t *tc, u32 start, u32 end)
	Build SACK list as per RFC2018. More...
u32	tcp_sack_list_bytes (tcp_connection_t *tc)
static u32	tcp_time_now (void)
static u32	tcp_set_time_now (u32 thread_index)
u32	tcp_push_header (tcp_connection_t *tconn, vlib_buffer_t *b)
void	tcp_connection_timers_init (tcp_connection_t *tc)
	Initialize all connection timers as invalid. More...
void	tcp_connection_timers_reset (tcp_connection_t *tc)
	Stop all connection timers. More...
void	tcp_init_snd_vars (tcp_connection_t *tc)
	Initialize connection send variables. More...
void	tcp_connection_init_vars (tcp_connection_t *tc)
	Initialize tcp connection variables. More...
static void	tcp_connection_force_ack (tcp_connection_t *tc, vlib_buffer_t *b)
static void	tcp_timer_set (tcp_connection_t *tc, u8 timer_id, u32 interval)
static void	tcp_timer_reset (tcp_connection_t *tc, u8 timer_id)
static void	tcp_timer_update (tcp_connection_t *tc, u8 timer_id, u32 interval)
static void	tcp_retransmit_timer_set (tcp_connection_t *tc)
static void	tcp_retransmit_timer_reset (tcp_connection_t *tc)
static void	tcp_retransmit_timer_force_update (tcp_connection_t *tc)
static void	tcp_persist_timer_set (tcp_connection_t *tc)
static void	tcp_persist_timer_update (tcp_connection_t *tc)
static void	tcp_persist_timer_reset (tcp_connection_t *tc)
static void	tcp_retransmit_timer_update (tcp_connection_t *tc)
static u8	tcp_timer_is_active (tcp_connection_t *tc, tcp_timers_e timer)
void	tcp_rcv_sacks (tcp_connection_t *tc, u32 ack)
u8 *	tcp_scoreboard_replay (u8 *s, tcp_connection_t *tc, u8 verbose)
void	tcp_cc_algo_register (tcp_cc_algorithm_type_e type, const tcp_cc_algorithm_t *vft)
tcp_cc_algorithm_t *	tcp_cc_algo_get (tcp_cc_algorithm_type_e type)
static void *	vlib_buffer_push_tcp_net_order (vlib_buffer_t *b, u16 sp, u16 dp, u32 seq, u32 ack, u8 tcp_hdr_opts_len, u8 flags, u16 wnd)
	Push TCP header to buffer. More...
static void *	vlib_buffer_push_tcp (vlib_buffer_t *b, u16 sp_net, u16 dp_net, u32 seq, u32 ack, u8 tcp_hdr_opts_len, u8 flags, u16 wnd)
	Push TCP header to buffer. More...

Variables
format_function_t	format_tcp_state
format_function_t	format_tcp_flags
format_function_t	format_tcp_sacks
format_function_t	format_tcp_rcv_sacks
timer_expiration_handler	tcp_timer_delack_handler
timer_expiration_handler	tcp_timer_retransmit_handler
timer_expiration_handler	tcp_timer_persist_handler
timer_expiration_handler	tcp_timer_retransmit_syn_handler
tcp_main_t	tcp_main
vlib_node_registration_t	tcp4_input_node
	(constructor) VLIB_REGISTER_NODE (tcp4_input_node) More...
vlib_node_registration_t	tcp6_input_node
	(constructor) VLIB_REGISTER_NODE (tcp6_input_node) More...
vlib_node_registration_t	tcp4_output_node
	(constructor) VLIB_REGISTER_NODE (tcp4_output_node) More...
vlib_node_registration_t	tcp6_output_node
	(constructor) VLIB_REGISTER_NODE (tcp6_output_node) More...

Macro Definition Documentation

#define foreach_tcp_buf_flag

Value:

_ (ACK)       /**< Sending ACK. */                    \
  _ (DUPACK)

TCP buffer flags.

Sending DUPACK.

Definition at line 141 of file tcp.h.

#define foreach_tcp_connection_flag

Value:

_(SNDACK, "Send ACK")                         \
  _(FINSNT, "FIN sent")                         \
  _(SENT_RCV_WND0, "Sent 0 rcv_wnd")            \
  _(RECOVERY, "Recovery")                       \
  _(FAST_RECOVERY, "Fast Recovery")             \
  _(FR_1_SMSS, "Sent 1 SMSS")                   \
  _(HALF_OPEN_DONE, "Half-open completed")      \
  _(FINPNDG, "FIN pending")                     \

TCP connection flags.

Definition at line 114 of file tcp.h.

#define foreach_tcp_fsm_state

Value:

_(CLOSED, "CLOSED")           \
  _(LISTEN, "LISTEN")           \
  _(SYN_SENT, "SYN_SENT")       \
  _(SYN_RCVD, "SYN_RCVD")       \
  _(ESTABLISHED, "ESTABLISHED") \
  _(CLOSE_WAIT, "CLOSE_WAIT")   \
  _(FIN_WAIT_1, "FIN_WAIT_1")   \
  _(LAST_ACK, "LAST_ACK")       \
  _(CLOSING, "CLOSING")         \
  _(FIN_WAIT_2, "FIN_WAIT_2")   \
  _(TIME_WAIT, "TIME_WAIT")

TCP FSM state definitions as per RFC793.

Definition at line 42 of file tcp.h.

#define foreach_tcp_timer

Value:

_(RETRANSMIT, "RETRANSMIT")           \
  _(DELACK, "DELAYED ACK")              \
  _(PERSIST, "PERSIST")                 \
  _(KEEP, "KEEP")                       \
  _(WAITCLOSE, "WAIT CLOSE")            \
  _(RETRANSMIT_SYN, "RETRANSMIT SYN")   \
  _(ESTABLISH, "ESTABLISH")

TCP timers.

Definition at line 69 of file tcp.h.

#define seq_geq	(		_s1,
			_s2
	)		((i32)((_s1)-(_s2)) >= 0)

Definition at line 549 of file tcp.h.

#define seq_gt	(		_s1,
			_s2
	)		((i32)((_s1)-(_s2)) > 0)

Definition at line 548 of file tcp.h.

#define seq_leq	(		_s1,
			_s2
	)		((i32)((_s1)-(_s2)) <= 0)

Definition at line 547 of file tcp.h.

#define seq_lt	(		_s1,
			_s2
	)		((i32)((_s1)-(_s2)) < 0)

Definition at line 546 of file tcp.h.

#define seq_max	(		_s1,
			_s2
	)		(seq_gt((_s1), (_s2)) ? (_s1) : (_s2))

Definition at line 550 of file tcp.h.

#define TCP_2MSL_TIME   300 /* 30s */

Definition at line 101 of file tcp.h.

#define TCP_ALWAYS_ACK   1

On/off delayed acks.

Definition at line 38 of file tcp.h.

#define TCP_CLEANUP_TIME   10 /* 1s Time to wait before cleanup */

Definition at line 104 of file tcp.h.

#define TCP_CLOSEWAIT_TIME   20 /* 2s */

Definition at line 102 of file tcp.h.

#define TCP_DELACK_TIME   1 /* 0.1s */

Definition at line 98 of file tcp.h.

#define TCP_DUPACK_THRESHOLD   3

Definition at line 34 of file tcp.h.

#define tcp_error	(		n,
			s
	)		TCP_ERROR_##n,

Definition at line 362 of file tcp.h.

#define TCP_ESTABLISH_TIME   750 /* 75s */

Definition at line 99 of file tcp.h.

#define tcp_fastrecovery_1_smss_off

(

tc

)

((tc)->flags &= ~TCP_CONN_FR_1_SMSS)

Definition at line 348 of file tcp.h.

#define tcp_fastrecovery_1_smss_on

(

tc

)

((tc)->flags |= TCP_CONN_FR_1_SMSS)

Definition at line 347 of file tcp.h.

#define tcp_fastrecovery_off

(

tc

)

(tc)->flags &= ~TCP_CONN_FAST_RECOVERY

Definition at line 340 of file tcp.h.

#define tcp_fastrecovery_on

(

tc

)

(tc)->flags |= TCP_CONN_FAST_RECOVERY

Definition at line 339 of file tcp.h.

#define tcp_fastrecovery_sent_1_smss

(

tc

)

((tc)->flags & TCP_CONN_FR_1_SMSS)

Definition at line 346 of file tcp.h.

#define TCP_FIB_RECHECK_PERIOD   1 * THZ

Recheck every 1s.

Definition at line 31 of file tcp.h.

#define tcp_in_cong_recovery

(

tc

)

Value:

((tc)->flags &          \
          (TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY))

Definition at line 350 of file tcp.h.

#define tcp_in_fastrecovery

(

tc

)

((tc)->flags & TCP_CONN_FAST_RECOVERY)

Definition at line 343 of file tcp.h.

#define tcp_in_recovery

(

tc

)

((tc)->flags & (TCP_CONN_RECOVERY))

Definition at line 344 of file tcp.h.

#define tcp_in_slowstart

(

tc

)

(tc->cwnd < tc->ssthresh)

Definition at line 345 of file tcp.h.

#define TCP_INVALID_SACK_HOLE_INDEX   ((u32)~0)

Definition at line 163 of file tcp.h.

#define TCP_IW_N_SEGMENTS   10

Definition at line 37 of file tcp.h.

#define TCP_MAX_OPTION_SPACE   40

Definition at line 32 of file tcp.h.

#define TCP_MAX_RX_FIFO_SIZE   4 << 20

Definition at line 35 of file tcp.h.

#define TCP_MAX_SACK_BLOCKS   15

Max number of SACK blocks stored.

Definition at line 162 of file tcp.h.

#define TCP_MIN_RX_FIFO_SIZE   4 << 10

Definition at line 36 of file tcp.h.

#define TCP_PAWS_IDLE   24 * 24 * 60 * 60 * THZ

24 days

Definition at line 30 of file tcp.h.

#define tcp_recovery_off

(

tc

)

(tc)->flags &= ~TCP_CONN_RECOVERY

Definition at line 342 of file tcp.h.

#define tcp_recovery_on

(

tc

)

(tc)->flags |= TCP_CONN_RECOVERY

Definition at line 341 of file tcp.h.

#define TCP_RTO_INIT   1 * THZ /* Initial retransmit timer */

Definition at line 111 of file tcp.h.

#define TCP_RTO_MAX   60 * THZ /* Min max RTO (60s) as per RFC6298 */

Definition at line 107 of file tcp.h.

#define TCP_RTO_MIN   0.2 * THZ /* Min RTO (200ms) - lower than standard */

Definition at line 108 of file tcp.h.

#define TCP_RTO_SYN_RETRIES   3 /* SYN retries without doubling RTO */

Definition at line 110 of file tcp.h.

#define TCP_RTT_MAX   30 * THZ /* 30s (probably too much) */

Definition at line 109 of file tcp.h.

#define TCP_SCOREBOARD_TRACE   (0)

Definition at line 161 of file tcp.h.

#define tcp_scoreboard_trace_add	(		_tc,
			_ack
	)

Definition at line 226 of file tcp.h.

#define TCP_SYN_RCVD_TIME   600 /* 60s */

Definition at line 100 of file tcp.h.

#define TCP_TICK   0.001

TCP tick period (s)

Definition at line 27 of file tcp.h.

#define TCP_TIMER_HANDLE_INVALID   ((u32) ~0)

Definition at line 93 of file tcp.h.

#define TCP_TIMER_PERSIST_MIN   2 /* 0.2s */

Definition at line 105 of file tcp.h.

#define TCP_TIMEWAIT_TIME   100 /* 10s */

Definition at line 103 of file tcp.h.

#define TCP_TO_TIMER_TICK

Value:

TCP_TICK*10     /* Period for converting from TCP
                                                 * ticks to timer units */

Definition at line 96 of file tcp.h.

#define tcp_trajectory_add_start	(		b,
			start
	)

Definition at line 461 of file tcp.h.

#define TCP_TSTAMP_RESOLUTION   TCP_TICK

Time stamp resolution.

Definition at line 29 of file tcp.h.

#define TCP_USE_SACKS   1

Disable only for testing.

Definition at line 39 of file tcp.h.

#define tcp_validate_txf_size	(		_tc,
			_a
	)

Value:

ASSERT(_tc->state != TCP_STATE_ESTABLISHED                              \
         || session_tx_fifo_max_dequeue (&_tc->connection) >= _a)

Definition at line 799 of file tcp.h.

#define THZ   (u32) (1/TCP_TICK)

TCP tick frequency.

Definition at line 28 of file tcp.h.

#define timestamp_leq	(		_t1,
			_t2
	)		((i32)((_t1)-(_t2)) <= 0)

Definition at line 554 of file tcp.h.

#define timestamp_lt	(		_t1,
			_t2
	)		((i32)((_t1)-(_t2)) < 0)

Definition at line 553 of file tcp.h.

Typedef Documentation

typedef struct _sack_scoreboard_hole sack_scoreboard_hole_t

typedef struct _sack_scoreboard sack_scoreboard_t

typedef struct _scoreboard_trace_elt scoreboard_trace_elt_t

typedef enum _tcp_cc_ack_t tcp_cc_ack_t

typedef struct _tcp_cc_algorithm tcp_cc_algorithm_t

Definition at line 252 of file tcp.h.

typedef enum _tcp_cc_algorithm_type tcp_cc_algorithm_type_e

typedef enum _tcp_connection_flag_bits tcp_connection_flag_bits_e

typedef enum _tcp_connection_flag tcp_connection_flags_e

typedef struct _tcp_connection tcp_connection_t

typedef enum _tcp_error tcp_error_t

typedef struct _tcp_lookup_dispatch tcp_lookup_dispatch_t

typedef struct _tcp_main tcp_main_t

typedef enum _tcp_state tcp_state_t

typedef enum _tcp_timers tcp_timers_e

typedef struct tcp_worker_ctx_ tcp_worker_ctx_t

typedef void( timer_expiration_handler) (u32 index)

Definition at line 86 of file tcp.h.

Enumeration Type Documentation

anonymous enum

Enumerator
TCP_N_BUF_BITS

Definition at line 146 of file tcp.h.

anonymous enum

Enumerator
foreach_tcp_buf_flag

Definition at line 154 of file tcp.h.

Function Documentation

u8* format_tcp_connection	(	u8 *	s,
		va_list *	args
	)

Definition at line 822 of file tcp.c.

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u8* format_tcp_scoreboard	(	u8 *	s,
		va_list *	args
	)

Definition at line 933 of file tcp.c.

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void scoreboard_clear

(

sack_scoreboard_t *

sb

)

Definition at line 783 of file tcp_input.c.

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sack_scoreboard_hole_t* scoreboard_first_hole

(

sack_scoreboard_t *

sb

)

Definition at line 575 of file tcp_input.c.

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sack_scoreboard_hole_t* scoreboard_get_hole	(	sack_scoreboard_t *	sb,
		u32	index
	)

Definition at line 551 of file tcp_input.c.

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void scoreboard_init

(

sack_scoreboard_t *

sb

)

Definition at line 775 of file tcp_input.c.

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sack_scoreboard_hole_t* scoreboard_last_hole

(

sack_scoreboard_t *

sb

)

Definition at line 583 of file tcp_input.c.

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sack_scoreboard_hole_t* scoreboard_next_hole	(	sack_scoreboard_t *	sb,
		sack_scoreboard_hole_t *	hole
	)

Definition at line 559 of file tcp_input.c.

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sack_scoreboard_hole_t* scoreboard_next_rxt_hole	(	sack_scoreboard_t *	sb,
		sack_scoreboard_hole_t *	start,
		u8	have_sent_1_smss,
		u8 *	can_rescue,
		u8 *	snd_limited
	)

Figure out the next hole to retransmit.

Follows logic proposed in RFC6675 Sec. 4, NextSeg()

Definition at line 707 of file tcp_input.c.

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sack_scoreboard_hole_t* scoreboard_prev_hole	(	sack_scoreboard_t *	sb,
		sack_scoreboard_hole_t *	hole
	)

Definition at line 567 of file tcp_input.c.

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void tcp_api_reference

(

void

)

Definition at line 109 of file tcp_api.c.

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static u32 tcp_available_cc_snd_space ( const tcp_connection_t *  tc )

inlinestatic

Estimate of how many bytes we can still push into the network.

Definition at line 635 of file tcp.h.

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static u32 tcp_available_output_snd_space ( const tcp_connection_t *  tc )

inlinestatic

Definition at line 620 of file tcp.h.

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static u32 tcp_available_snd_wnd ( const tcp_connection_t *  tc )

inlinestatic

Definition at line 614 of file tcp.h.

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static tcp_header_t* tcp_buffer_hdr ( vlib_buffer_t *  b )

inlinestatic

Definition at line 448 of file tcp.h.

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static u32 tcp_bytes_out ( const tcp_connection_t *  tc )

inlinestatic

Our estimate of the number of bytes that have left the network.

Definition at line 560 of file tcp.h.

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tcp_cc_algorithm_t* tcp_cc_algo_get

(

tcp_cc_algorithm_type_e

type

)

Definition at line 525 of file tcp.c.

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void tcp_cc_algo_register	(	tcp_cc_algorithm_type_e	type,
		const tcp_cc_algorithm_t *	vft
	)

Definition at line 515 of file tcp.c.

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void tcp_cc_fastrecovery_exit

(

tcp_connection_t *

tc

)

Definition at line 1051 of file tcp_input.c.

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void tcp_cc_init_congestion

(

tcp_connection_t *

tc

)

Init loss recovery/fast recovery.

Triggered by dup acks as opposed to timer timeout. Note that cwnd is updated in tcp_cc_handle_event after fast retransmit

Definition at line 1030 of file tcp_input.c.

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int tcp_configure_v4_source_address_range	(	vlib_main_t *	vm,
		ip4_address_t *	start,
		ip4_address_t *	end,
		u32	table_id
	)

Configure an ipv4 source address range.

Parameters

vm	vlib_main_t pointer
start	first ipv4 address in the source address range
end	last ipv4 address in the source address range
table_id	VRF / table ID, 0 for the default FIB

Returns

0 if all OK, else an error indication from api_errno.h

Definition at line 1421 of file tcp.c.

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int tcp_configure_v6_source_address_range	(	vlib_main_t *	vm,
		ip6_address_t *	start,
		ip6_address_t *	end,
		u32	table_id
	)

Configure an ipv6 source address range.

Parameters

vm	vlib_main_t pointer
start	first ipv6 address in the source address range
end	last ipv6 address in the source address range
table_id	VRF / table ID, 0 for the default FIB

Returns

0 if all OK, else an error indication from api_errno.h

Definition at line 1513 of file tcp.c.

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static void tcp_cong_recovery_off ( tcp_connection_t *  tc )

inlinestatic

Definition at line 354 of file tcp.h.

void tcp_connection_cleanup

(

tcp_connection_t *

tc

)

Cleans up connection state.

No notifications.

Definition at line 199 of file tcp.c.

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void tcp_connection_close

(

tcp_connection_t *

tc

)

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

Definition at line 314 of file tcp.c.

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void tcp_connection_del

(

tcp_connection_t *

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.

Definition at line 240 of file tcp.c.

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static void tcp_connection_force_ack ( tcp_connection_t *  tc, vlib_buffer_t *  b  )

inlinestatic

Definition at line 689 of file tcp.h.

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static tcp_connection_t* tcp_connection_get ( u32  conn_index, u32  thread_index  )

inlinestatic

Definition at line 469 of file tcp.h.

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static tcp_connection_t* tcp_connection_get_if_valid ( u32  conn_index, u32  thread_index  )

inlinestatic

Definition at line 478 of file tcp.h.

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void tcp_connection_init_vars

(

tcp_connection_t *

tc

)

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.

Definition at line 560 of file tcp.c.

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tcp_connection_t* tcp_connection_new

(

u8

thread_index

)

Definition at line 248 of file tcp.c.

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void tcp_connection_reset

(

tcp_connection_t *

tc

)

Notify session that connection has been reset.

Switch state to closed and wait for session to call cleanup.

Definition at line 265 of file tcp.c.

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void tcp_connection_timers_init

(

tcp_connection_t *

tc

)

Initialize all connection timers as invalid.

Definition at line 384 of file tcp.c.

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void tcp_connection_timers_reset

(

tcp_connection_t *

tc

)

Stop all connection timers.

Definition at line 401 of file tcp.c.

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static u32 tcp_end_seq ( tcp_header_t *  th, u32  len  )

inlinestatic

Definition at line 540 of file tcp.h.

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void tcp_fast_retransmit

(

tcp_connection_t *

tc

)

Do fast retransmit.

Definition at line 1805 of file tcp_output.c.

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void tcp_fast_retransmit_no_sack

(

tcp_connection_t *

tc

)

Fast retransmit without SACK info.

Definition at line 1768 of file tcp_output.c.

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void tcp_fast_retransmit_sack

(

tcp_connection_t *

tc

)

Do fast retransmit with SACKs.

Definition at line 1685 of file tcp_output.c.

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static u32 tcp_flight_size ( const tcp_connection_t *  tc )

inlinestatic

Our estimate of the number of bytes in flight (pipe size)

Definition at line 572 of file tcp.h.

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void tcp_flush_frame_to_output	(	vlib_main_t *	vm,
		u8	thread_index,
		u8	is_ip4
	)

Flush tx frame populated by retransmits and timer pops.

Definition at line 1022 of file tcp_output.c.

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void tcp_flush_frames_to_output

(

u8

thread_index

)

Flush v4 and v6 tcp and ip-lookup tx frames for thread index.

Definition at line 1057 of file tcp_output.c.

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static tcp_connection_t* tcp_get_connection_from_transport ( transport_connection_t *  tconn )

inlinestatic

Definition at line 488 of file tcp.h.

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int tcp_half_open_connection_cleanup

(

tcp_connection_t *

tc

)

Try to cleanup half-open connection.

If called from a thread that doesn't own tc, the call won't have any effect.

Parameters

tc	- connection to be cleaned up

Returns

non-zero if cleanup failed.

Definition at line 170 of file tcp.c.

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static tcp_connection_t* tcp_half_open_connection_get ( u32  conn_index )

inlinestatic

Definition at line 515 of file tcp.h.

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void tcp_init_mss

(

tcp_connection_t *

tc

)

Definition at line 436 of file tcp_output.c.

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void tcp_init_snd_vars

(

tcp_connection_t *

tc

)

Initialize connection send variables.

Definition at line 536 of file tcp.c.

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static u32 tcp_initial_cwnd ( const tcp_connection_t *  tc )

inlinestatic

Initial cwnd as per RFC5681.

Definition at line 597 of file tcp.h.

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static u8 tcp_is_lost_fin ( tcp_connection_t *  tc )

inlinestatic

Definition at line 647 of file tcp.h.

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static tcp_connection_t* tcp_listener_get ( u32  tli )

inlinestatic

Definition at line 509 of file tcp.h.

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fib_node_index_t tcp_lookup_rmt_in_fib

(

tcp_connection_t *

tc

)

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static u32 tcp_loss_wnd ( const tcp_connection_t *  tc )

inlinestatic

Definition at line 608 of file tcp.h.

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void tcp_make_ack	(	tcp_connection_t *	ts,
		vlib_buffer_t *	b
	)

Convert buffer to ACK.

Definition at line 558 of file tcp_output.c.

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void tcp_make_fin	(	tcp_connection_t *	tc,
		vlib_buffer_t *	b
	)

Convert buffer to FIN-ACK.

Definition at line 573 of file tcp_output.c.

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void tcp_make_synack	(	tcp_connection_t *	ts,
		vlib_buffer_t *	b
	)

Convert buffer to SYN-ACK.

Definition at line 616 of file tcp_output.c.

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static void tcp_persist_timer_reset ( tcp_connection_t *  tc )

inlinestatic

Definition at line 774 of file tcp.h.

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static void tcp_persist_timer_set ( tcp_connection_t *  tc )

inlinestatic

Definition at line 757 of file tcp.h.

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static void tcp_persist_timer_update ( tcp_connection_t *  tc )

inlinestatic

Definition at line 766 of file tcp.h.

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void tcp_punt_unknown	(	vlib_main_t *	vm,
		u8	is_ip4,
		u8	is_add
	)

Definition at line 1346 of file tcp.c.

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u32 tcp_push_header	(	tcp_connection_t *	tconn,
		vlib_buffer_t *	b
	)

Definition at line 1185 of file tcp_output.c.

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void tcp_rcv_sacks	(	tcp_connection_t *	tc,
		u32	ack
	)

Definition at line 817 of file tcp_input.c.

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void tcp_retransmit_first_unacked

(

tcp_connection_t *

tc

)

Retransmit first unacked segment.

Definition at line 1662 of file tcp_output.c.

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static void tcp_retransmit_timer_force_update ( tcp_connection_t *  tc )

inlinestatic

Definition at line 750 of file tcp.h.

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static void tcp_retransmit_timer_reset ( tcp_connection_t *  tc )

inlinestatic

Definition at line 744 of file tcp.h.

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static void tcp_retransmit_timer_set ( tcp_connection_t *  tc )

inlinestatic

Definition at line 736 of file tcp.h.

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static void tcp_retransmit_timer_update ( tcp_connection_t *  tc )

inlinestatic

Definition at line 780 of file tcp.h.

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u32 tcp_sack_list_bytes

(

tcp_connection_t *

tc

)

Definition at line 1484 of file tcp_input.c.

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u8* tcp_scoreboard_replay	(	u8 *	s,
		tcp_connection_t *	tc,
		u8	verbose
	)

Definition at line 1737 of file tcp.c.

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void tcp_send_fin

(

tcp_connection_t *

tc

)

Send FIN.

Definition at line 1070 of file tcp_output.c.

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void tcp_send_reset

(

tcp_connection_t *

tc

)

Build and set reset packet for connection.

Definition at line 909 of file tcp_output.c.

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void tcp_send_reset_w_pkt	(	tcp_connection_t *	tc,
		vlib_buffer_t *	pkt,
		u8	is_ip4
	)

Send reset without reusing existing buffer.

It extracts connection info out of original packet

Definition at line 830 of file tcp_output.c.

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void tcp_send_syn

(

tcp_connection_t *

tc

)

Send SYN.

Builds a SYN packet for a half-open connection and sends it to ipx_lookup. The packet is not forwarded through tcpx_output to avoid doing lookups in the half_open pool.

Definition at line 986 of file tcp_output.c.

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static u32 tcp_set_time_now ( u32  thread_index )

inlinestatic

Definition at line 674 of file tcp.h.

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static u32 tcp_time_now ( void  )

inlinestatic

Definition at line 668 of file tcp.h.

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static u8 tcp_timer_is_active ( tcp_connection_t *  tc, tcp_timers_e  timer  )

inlinestatic

Definition at line 794 of file tcp.h.

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static void tcp_timer_reset ( tcp_connection_t *  tc, u8  timer_id  )

inlinestatic

Definition at line 708 of file tcp.h.

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static void tcp_timer_set ( tcp_connection_t *  tc, u8  timer_id, u32  interval  )

inlinestatic

Definition at line 697 of file tcp.h.

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static void tcp_timer_update ( tcp_connection_t *  tc, u8  timer_id, u32  interval  )

inlinestatic

Definition at line 721 of file tcp.h.

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void tcp_update_burst_snd_vars

(

tcp_connection_t *

tc

)

Update burst send vars.

• Updates snd_mss to reflect the effective segment size that we can send by taking into account all TCP options, including SACKs.
• Cache 'on the wire' options for reuse
• Updates receive window which can be reused for a burst.

This should only be called when doing bursts

Definition at line 416 of file tcp_output.c.

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void tcp_update_rto

(

tcp_connection_t *

tc

)

Definition at line 431 of file tcp_input.c.

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void tcp_update_sack_list	(	tcp_connection_t *	tc,
		u32	start,
		u32	end
	)

Build SACK list as per RFC2018.

Makes sure the first block contains the segment that generated the current ACK and the following ones are the ones most recently reported in SACK blocks.

Parameters

tc	TCP connection for which the SACK list is updated
start	Start sequence number of the newest SACK block
end	End sequence of the newest SACK block

Definition at line 1430 of file tcp_input.c.

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static void* vlib_buffer_push_tcp ( vlib_buffer_t *  b, u16  sp_net, u16  dp_net, u32  seq, u32  ack, u8  tcp_hdr_opts_len, u8  flags, u16  wnd  )

inlinestatic

Push TCP header to buffer.

Parameters

b	- buffer to write the header to
sp_net	- source port net order
dp_net	- destination port net order
seq	- sequence number host order
ack	- ack number host order
tcp_hdr_opts_len	- header and options length in bytes
flags	- header flags
wnd	- window size

Returns

- pointer to start of TCP header

Definition at line 862 of file tcp.h.

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static void* vlib_buffer_push_tcp_net_order ( vlib_buffer_t *  b, u16  sp, u16  dp, u32  seq, u32  ack, u8  tcp_hdr_opts_len, u8  flags, u16  wnd  )

inlinestatic

Push TCP header to buffer.

Parameters

vm	- vlib_main
b	- buffer to write the header to
sp_net	- source port net order
dp_net	- destination port net order
seq	- sequence number net order
ack	- ack number net order
tcp_hdr_opts_len	- header and options length in bytes
flags	- header flags
wnd	- window size

Returns

- pointer to start of TCP header

Definition at line 827 of file tcp.h.

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static tcp_main_t* vnet_get_tcp_main ( )

inlinestatic

Definition at line 442 of file tcp.h.

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clib_error_t* vnet_tcp_enable_disable	(	vlib_main_t *	vm,
		u8	is_en
	)

Definition at line 1328 of file tcp.c.

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Variable Documentation

format_function_t format_tcp_flags

Definition at line 64 of file tcp.h.

format_function_t format_tcp_rcv_sacks

Definition at line 66 of file tcp.h.

format_function_t format_tcp_sacks

Definition at line 65 of file tcp.h.

format_function_t format_tcp_state

Definition at line 63 of file tcp.h.

vlib_node_registration_t tcp4_input_node

Initial value:

=
{
  .function = tcp4_input,
  .name = "tcp4-input",
  
  .vector_size = sizeof (u32),
  .n_errors = TCP_N_ERROR,
  .error_strings = tcp_error_strings,
  .n_next_nodes = TCP_INPUT_N_NEXT,
  .next_nodes =
  {
#define _(s,n) 
    foreach_tcp4_input_next

  },
  .format_buffer = format_tcp_header,
  .format_trace = format_tcp_rx_trace,
}

(constructor) VLIB_REGISTER_NODE (tcp4_input_node)

Definition at line 3364 of file tcp_input.c.

vlib_node_registration_t tcp4_output_node

Initial value:

=
{
  .function = tcp4_output,.name = "tcp4-output",
    
    .vector_size = sizeof (u32),
    .n_errors = TCP_N_ERROR,
    .error_strings = tcp_error_strings,
    .n_next_nodes = TCP_OUTPUT_N_NEXT,
    .next_nodes = {
#define _(s,n) 
    foreach_tcp4_output_next

    },
    .format_buffer = format_tcp_header,
    .format_trace = format_tcp_tx_trace,
}

(constructor) VLIB_REGISTER_NODE (tcp4_output_node)

Definition at line 2038 of file tcp_output.c.

vlib_node_registration_t tcp6_input_node

Initial value:

=
{
  .function = tcp6_input,
  .name = "tcp6-input",
  
  .vector_size = sizeof (u32),
  .n_errors = TCP_N_ERROR,
  .error_strings = tcp_error_strings,
  .n_next_nodes = TCP_INPUT_N_NEXT,
  .next_nodes =
  {
#define _(s,n) 
    foreach_tcp6_input_next

  },
  .format_buffer = format_tcp_header,
  .format_trace = format_tcp_rx_trace,
}

(constructor) VLIB_REGISTER_NODE (tcp6_input_node)

Definition at line 3387 of file tcp_input.c.

vlib_node_registration_t tcp6_output_node

Initial value:

=
{
  .function = tcp6_output,
  .name = "tcp6-output",
    
  .vector_size = sizeof (u32),
  .n_errors = TCP_N_ERROR,
  .error_strings = tcp_error_strings,
  .n_next_nodes = TCP_OUTPUT_N_NEXT,
  .next_nodes = {
#define _(s,n) 
    foreach_tcp6_output_next

  },
  .format_buffer = format_tcp_header,
  .format_trace = format_tcp_tx_trace,
}

(constructor) VLIB_REGISTER_NODE (tcp6_output_node)

Definition at line 2059 of file tcp_output.c.

tcp_main_t tcp_main

Definition at line 29 of file tcp.c.

timer_expiration_handler tcp_timer_delack_handler

timer_expiration_handler tcp_timer_persist_handler

timer_expiration_handler tcp_timer_retransmit_handler

timer_expiration_handler tcp_timer_retransmit_syn_handler