2 * Copyright (c) 2016-2019 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
19 #include <vnet/vnet.h>
20 #include <vnet/ip/ip.h>
21 #include <vnet/tcp/tcp_packet.h>
22 #include <vnet/tcp/tcp_timer.h>
23 #include <vnet/session/transport.h>
24 #include <vnet/session/session.h>
25 #include <vnet/tcp/tcp_debug.h>
27 #define TCP_TICK 0.001 /**< TCP tick period (s) */
28 #define THZ (u32) (1/TCP_TICK) /**< TCP tick frequency */
29 #define TCP_TSTAMP_RESOLUTION TCP_TICK /**< Time stamp resolution */
30 #define TCP_PAWS_IDLE 24 * 24 * 60 * 60 * THZ /**< 24 days */
31 #define TCP_FIB_RECHECK_PERIOD 1 * THZ /**< Recheck every 1s */
32 #define TCP_MAX_OPTION_SPACE 40
33 #define TCP_CC_DATA_SZ 24
34 #define TCP_MAX_GSO_SZ 65536
35 #define TCP_RXT_MAX_BURST 10
37 #define TCP_DUPACK_THRESHOLD 3
38 #define TCP_IW_N_SEGMENTS 10
39 #define TCP_ALWAYS_ACK 1 /**< On/off delayed acks */
40 #define TCP_USE_SACKS 1 /**< Disable only for testing */
42 /** TCP FSM state definitions as per RFC793. */
43 #define foreach_tcp_fsm_state \
46 _(SYN_SENT, "SYN_SENT") \
47 _(SYN_RCVD, "SYN_RCVD") \
48 _(ESTABLISHED, "ESTABLISHED") \
49 _(CLOSE_WAIT, "CLOSE_WAIT") \
50 _(FIN_WAIT_1, "FIN_WAIT_1") \
51 _(LAST_ACK, "LAST_ACK") \
52 _(CLOSING, "CLOSING") \
53 _(FIN_WAIT_2, "FIN_WAIT_2") \
54 _(TIME_WAIT, "TIME_WAIT")
56 typedef enum _tcp_state
58 #define _(sym, str) TCP_STATE_##sym,
64 format_function_t format_tcp_state;
65 format_function_t format_tcp_flags;
66 format_function_t format_tcp_sacks;
67 format_function_t format_tcp_rcv_sacks;
70 #define foreach_tcp_timer \
71 _(RETRANSMIT, "RETRANSMIT") \
72 _(DELACK, "DELAYED ACK") \
73 _(PERSIST, "PERSIST") \
74 _(WAITCLOSE, "WAIT CLOSE") \
75 _(RETRANSMIT_SYN, "RETRANSMIT SYN") \
77 typedef enum _tcp_timers
79 #define _(sym, str) TCP_TIMER_##sym,
85 typedef void (timer_expiration_handler) (u32 index);
87 extern timer_expiration_handler tcp_timer_delack_handler;
88 extern timer_expiration_handler tcp_timer_retransmit_handler;
89 extern timer_expiration_handler tcp_timer_persist_handler;
90 extern timer_expiration_handler tcp_timer_retransmit_syn_handler;
92 #define TCP_TIMER_HANDLE_INVALID ((u32) ~0)
94 #define TCP_TIMER_TICK 0.1 /**< Timer tick in seconds */
95 #define TCP_TO_TIMER_TICK TCP_TICK*10 /**< Factor for converting
96 ticks to timer ticks */
98 #define TCP_RTO_MAX 60 * THZ /* Min max RTO (60s) as per RFC6298 */
99 #define TCP_RTO_MIN 0.2 * THZ /* Min RTO (200ms) - lower than standard */
100 #define TCP_RTT_MAX 30 * THZ /* 30s (probably too much) */
101 #define TCP_RTO_SYN_RETRIES 3 /* SYN retries without doubling RTO */
102 #define TCP_RTO_INIT 1 * THZ /* Initial retransmit timer */
103 #define TCP_RTO_BOFF_MAX 8 /* Max number of retries before reset */
104 #define TCP_ESTABLISH_TIME (60 * THZ) /* Connection establish timeout */
106 /** TCP connection flags */
107 #define foreach_tcp_connection_flag \
108 _(SNDACK, "Send ACK") \
109 _(FINSNT, "FIN sent") \
110 _(RECOVERY, "Recovery") \
111 _(FAST_RECOVERY, "Fast Recovery") \
112 _(DCNT_PENDING, "Disconnect pending") \
113 _(HALF_OPEN_DONE, "Half-open completed") \
114 _(FINPNDG, "FIN pending") \
115 _(RXT_PENDING, "Retransmit pending") \
116 _(FRXT_FIRST, "Fast-retransmit first again") \
117 _(DEQ_PENDING, "Pending dequeue acked") \
118 _(PSH_PENDING, "PSH pending") \
119 _(FINRCVD, "FIN received") \
120 _(RATE_SAMPLE, "Conn does rate sampling") \
121 _(TRACK_BURST, "Track burst") \
122 _(ZERO_RWND_SENT, "Zero RWND sent") \
123 _(NO_CSUM_OFFLOAD, "No Checksum Offload") \
125 typedef enum _tcp_connection_flag_bits
127 #define _(sym, str) TCP_CONN_##sym##_BIT,
128 foreach_tcp_connection_flag
131 } tcp_connection_flag_bits_e;
133 typedef enum _tcp_connection_flag
135 #define _(sym, str) TCP_CONN_##sym = 1 << TCP_CONN_##sym##_BIT,
136 foreach_tcp_connection_flag
139 } tcp_connection_flags_e;
141 #define TCP_SCOREBOARD_TRACE (0)
142 #define TCP_MAX_SACK_BLOCKS 256 /**< Max number of SACK blocks stored */
143 #define TCP_INVALID_SACK_HOLE_INDEX ((u32)~0)
145 typedef struct _scoreboard_trace_elt
152 } scoreboard_trace_elt_t;
154 typedef struct _sack_scoreboard_hole
156 u32 next; /**< Index for next entry in linked list */
157 u32 prev; /**< Index for previous entry in linked list */
158 u32 start; /**< Start sequence number */
159 u32 end; /**< End sequence number */
160 u8 is_lost; /**< Mark hole as lost */
161 } sack_scoreboard_hole_t;
163 typedef struct _sack_scoreboard
165 sack_scoreboard_hole_t *holes; /**< Pool of holes */
166 u32 head; /**< Index of first entry */
167 u32 tail; /**< Index of last entry */
168 u32 sacked_bytes; /**< Number of bytes sacked in sb */
169 u32 last_sacked_bytes; /**< Number of bytes last sacked */
170 u32 last_bytes_delivered; /**< Sack bytes delivered to app */
171 u32 rxt_sacked; /**< Rxt bytes last delivered */
172 u32 high_sacked; /**< Highest byte sacked (fack) */
173 u32 high_rxt; /**< Highest retransmitted sequence */
174 u32 rescue_rxt; /**< Rescue sequence number */
175 u32 lost_bytes; /**< Bytes lost as per RFC6675 */
176 u32 last_lost_bytes; /**< Number of bytes last lost */
177 u32 cur_rxt_hole; /**< Retransmitting from this hole */
180 #if TCP_SCOREBOARD_TRACE
181 scoreboard_trace_elt_t *trace;
186 #if TCP_SCOREBOARD_TRACE
187 #define tcp_scoreboard_trace_add(_tc, _ack) \
189 static u64 _group = 0; \
190 sack_scoreboard_t *_sb = &_tc->sack_sb; \
191 sack_block_t *_sack, *_sacks; \
192 scoreboard_trace_elt_t *_elt; \
195 _sacks = _tc->rcv_opts.sacks; \
196 for (i = 0; i < vec_len (_sacks); i++) \
198 _sack = &_sacks[i]; \
199 vec_add2 (_sb->trace, _elt, 1); \
200 _elt->start = _sack->start; \
201 _elt->end = _sack->end; \
202 _elt->ack = _elt->end == _ack ? _ack : 0; \
203 _elt->snd_una_max = _elt->end == _ack ? _tc->snd_una_max : 0; \
204 _elt->group = _group; \
208 #define tcp_scoreboard_trace_add(_tc, _ack)
211 sack_scoreboard_hole_t *scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
212 sack_scoreboard_hole_t *
213 start, u8 have_sent_1_smss,
216 sack_scoreboard_hole_t *scoreboard_get_hole (sack_scoreboard_t * sb,
219 sack_scoreboard_hole_t *scoreboard_next_hole (sack_scoreboard_t * sb,
220 sack_scoreboard_hole_t * hole);
221 sack_scoreboard_hole_t *scoreboard_prev_hole (sack_scoreboard_t * sb,
222 sack_scoreboard_hole_t * hole);
223 sack_scoreboard_hole_t *scoreboard_first_hole (sack_scoreboard_t * sb);
224 sack_scoreboard_hole_t *scoreboard_last_hole (sack_scoreboard_t * sb);
226 void scoreboard_clear (sack_scoreboard_t * sb);
227 void scoreboard_clear_reneging (sack_scoreboard_t * sb, u32 start, u32 end);
228 void scoreboard_init (sack_scoreboard_t * sb);
229 void scoreboard_init_rxt (sack_scoreboard_t * sb, u32 snd_una);
230 u8 *format_tcp_scoreboard (u8 * s, va_list * args);
232 #define TCP_BTS_INVALID_INDEX ((u32)~0)
234 typedef enum tcp_bts_flags_
237 TCP_BTS_IS_APP_LIMITED = 1 << 1,
238 } __clib_packed tcp_bts_flags_t;
240 typedef struct tcp_bt_sample_
242 u32 next; /**< Next sample index in list */
243 u32 prev; /**< Previous sample index in list */
244 u32 min_seq; /**< Min seq number in sample */
245 u32 max_seq; /**< Max seq number. Set for rxt samples */
246 u64 delivered; /**< Total delivered bytes for sample */
247 f64 delivered_time; /**< Delivered time when sample taken */
248 f64 tx_time; /**< Transmit time for the burst */
249 f64 first_tx_time; /**< Connection first tx time at tx */
250 tcp_bts_flags_t flags; /**< Sample flag */
253 typedef struct tcp_rate_sample_
255 u64 prior_delivered; /**< Delivered of sample used for rate, i.e.,
256 total bytes delivered at prior_time */
257 f64 prior_time; /**< Delivered time of sample used for rate */
258 f64 interval_time; /**< Time to ack the bytes delivered */
259 f64 rtt_time; /**< RTT for sample */
260 u32 delivered; /**< Bytes delivered in interval_time */
261 u32 acked_and_sacked; /**< Bytes acked + sacked now */
262 u32 lost; /**< Bytes lost now */
263 tcp_bts_flags_t flags; /**< Rate sample flags from bt sample */
266 typedef struct tcp_byte_tracker_
268 tcp_bt_sample_t *samples; /**< Pool of samples */
269 rb_tree_t sample_lookup; /**< Rbtree for sample lookup by min_seq */
270 u32 head; /**< Head of samples linked list */
271 u32 tail; /**< Tail of samples linked list */
272 u32 last_ooo; /**< Cached last ooo sample */
273 } tcp_byte_tracker_t;
275 typedef enum _tcp_cc_algorithm_type
279 TCP_CC_LAST = TCP_CC_CUBIC
280 } tcp_cc_algorithm_type_e;
282 typedef struct _tcp_cc_algorithm tcp_cc_algorithm_t;
284 typedef enum _tcp_cc_ack_t
291 typedef enum tcp_cc_event_
297 * As per RFC4898 tcpEStatsStackSoftErrors
299 typedef struct tcp_errors_
301 u32 below_data_wnd; /**< All data in seg is below snd_una */
302 u32 above_data_wnd; /**< Some data in segment is above snd_wnd */
303 u32 below_ack_wnd; /**< Acks for data below snd_una */
304 u32 above_ack_wnd; /**< Acks for data not sent */
307 typedef struct _tcp_connection
309 CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
310 transport_connection_t connection; /**< Common transport data. First! */
312 u8 state; /**< TCP state as per tcp_state_t */
313 u8 is_tso; /** is connection could use tso */
314 u16 flags; /**< Connection flags (see tcp_conn_flags_e) */
315 u32 timers[TCP_N_TIMERS]; /**< Timer handles into timer wheel */
317 u64 segs_in; /** RFC4022/4898 tcpHCInSegs/tcpEStatsPerfSegsIn */
318 u64 bytes_in; /** RFC4898 tcpEStatsPerfHCDataOctetsIn */
319 u64 segs_out; /** RFC4898 tcpEStatsPerfSegsOut */
320 u64 bytes_out; /** RFC4898 tcpEStatsPerfHCDataOctetsOut */
322 /** Send sequence variables RFC793 */
323 u32 snd_una; /**< oldest unacknowledged sequence number */
324 u32 snd_una_max; /**< newest unacknowledged sequence number + 1*/
325 u32 snd_wnd; /**< send window */
326 u32 snd_wl1; /**< seq number used for last snd.wnd update */
327 u32 snd_wl2; /**< ack number used for last snd.wnd update */
328 u32 snd_nxt; /**< next seq number to be sent */
329 u16 snd_mss; /**< Effective send max seg (data) size */
331 u64 data_segs_in; /** RFC4898 tcpEStatsPerfDataSegsIn */
332 u64 data_segs_out; /** RFC4898 tcpEStatsPerfDataSegsOut */
334 /** Receive sequence variables RFC793 */
335 u32 rcv_nxt; /**< next sequence number expected */
336 u32 rcv_wnd; /**< receive window we expect */
338 u32 rcv_las; /**< rcv_nxt at last ack sent/rcv_wnd update */
339 u32 iss; /**< initial sent sequence */
340 u32 irs; /**< initial remote sequence */
343 u8 snd_opts_len; /**< Tx options len */
344 u8 rcv_wscale; /**< Window scale to advertise to peer */
345 u8 snd_wscale; /**< Window scale to use when sending */
346 u32 tsval_recent; /**< Last timestamp received */
347 u32 tsval_recent_age; /**< When last updated tstamp_recent*/
348 tcp_options_t snd_opts; /**< Tx options for connection */
349 tcp_options_t rcv_opts; /**< Rx options for connection */
351 sack_block_t *snd_sacks; /**< Vector of SACKs to send. XXX Fixed size? */
352 u8 snd_sack_pos; /**< Position in vec of first block to send */
353 sack_block_t *snd_sacks_fl; /**< Vector for building new list */
354 sack_scoreboard_t sack_sb; /**< SACK "scoreboard" that tracks holes */
356 u16 rcv_dupacks; /**< Number of recent DUPACKs received */
357 u32 dupacks_in; /**< RFC4898 tcpEStatsStackDupAcksIn*/
358 u8 pending_dupacks; /**< Number of DUPACKs to be sent */
359 u32 dupacks_out; /**< RFC4898 tcpEStatsPathDupAcksOut */
361 /* Congestion control */
362 u32 cwnd; /**< Congestion window */
363 u32 cwnd_acc_bytes; /**< Bytes accumulated for cwnd increment */
364 u32 ssthresh; /**< Slow-start threshold */
365 u32 prev_ssthresh; /**< ssthresh before congestion */
366 u32 prev_cwnd; /**< ssthresh before congestion */
367 u32 bytes_acked; /**< Bytes acknowledged by current segment */
368 u32 burst_acked; /**< Bytes acknowledged in current burst */
369 u32 snd_rxt_bytes; /**< Retransmitted bytes during current cc event */
370 u32 snd_rxt_ts; /**< Timestamp when first packet is retransmitted */
371 u32 prr_delivered; /**< RFC6937 bytes delivered during current event */
372 u32 prr_start; /**< snd_una when prr starts */
373 u32 rxt_delivered; /**< Rxt bytes delivered during current cc event */
374 u32 rxt_head; /**< snd_una last time we re rxted the head */
375 u32 tsecr_last_ack; /**< Timestamp echoed to us in last healthy ACK */
376 u32 snd_congestion; /**< snd_una_max when congestion is detected */
377 u32 tx_fifo_size; /**< Tx fifo size. Used to constrain cwnd */
378 tcp_cc_algorithm_t *cc_algo; /**< Congestion control algorithm */
379 u8 cc_data[TCP_CC_DATA_SZ]; /**< Congestion control algo private data */
381 u32 fr_occurences; /**< fast-retransmit occurrences RFC4898
382 tcpEStatsStackFastRetran */
383 u32 tr_occurences; /**< timer-retransmit occurrences */
384 u64 bytes_retrans; /**< RFC4898 tcpEStatsPerfOctetsRetrans */
385 u64 segs_retrans; /**< RFC4898 tcpEStatsPerfSegsRetrans*/
388 u32 rto; /**< Retransmission timeout */
389 u32 rto_boff; /**< Index for RTO backoff */
390 u32 srtt; /**< Smoothed RTT */
391 u32 rttvar; /**< Smoothed mean RTT difference. Approximates variance */
392 u32 rtt_seq; /**< Sequence number for tracked ACK */
393 f64 rtt_ts; /**< Timestamp for tracked ACK */
394 f64 mrtt_us; /**< High precision mrtt from tracked acks */
396 u32 psh_seq; /**< Add psh header for seg that includes this */
397 u32 next_node_index; /**< Can be used to control next node in output */
398 u32 next_node_opaque; /**< Opaque to pass to next node */
399 u32 limited_transmit; /**< snd_nxt when limited transmit starts */
400 u32 sw_if_index; /**< Interface for the connection */
402 /* Delivery rate estimation */
403 u64 delivered; /**< Total bytes delivered to peer */
404 u64 app_limited; /**< Delivered when app-limited detected */
405 f64 delivered_time; /**< Time last bytes were acked */
406 f64 first_tx_time; /**< Send time for recently delivered/sent */
407 tcp_byte_tracker_t *bt; /**< Tx byte tracker */
409 tcp_errors_t errors; /**< Soft connection errors */
411 f64 start_ts; /**< Timestamp when connection initialized */
412 u32 last_fib_check; /**< Last time we checked fib route for peer */
413 u16 mss; /**< Our max seg size that includes options */
414 u32 timestamp_delta; /**< Offset for timestamp */
418 struct _tcp_cc_algorithm
421 uword (*unformat_cfg) (unformat_input_t * input);
422 void (*init) (tcp_connection_t * tc);
423 void (*cleanup) (tcp_connection_t * tc);
424 void (*rcv_ack) (tcp_connection_t * tc, tcp_rate_sample_t *rs);
425 void (*rcv_cong_ack) (tcp_connection_t * tc, tcp_cc_ack_t ack,
426 tcp_rate_sample_t *rs);
427 void (*congestion) (tcp_connection_t * tc);
428 void (*loss) (tcp_connection_t * tc);
429 void (*recovered) (tcp_connection_t * tc);
430 void (*undo_recovery) (tcp_connection_t * tc);
431 void (*event) (tcp_connection_t *tc, tcp_cc_event_t evt);
432 u64 (*get_pacing_rate) (tcp_connection_t *tc);
436 #define tcp_fastrecovery_on(tc) (tc)->flags |= TCP_CONN_FAST_RECOVERY
437 #define tcp_fastrecovery_off(tc) (tc)->flags &= ~TCP_CONN_FAST_RECOVERY
438 #define tcp_recovery_on(tc) (tc)->flags |= TCP_CONN_RECOVERY
439 #define tcp_recovery_off(tc) (tc)->flags &= ~TCP_CONN_RECOVERY
440 #define tcp_in_fastrecovery(tc) ((tc)->flags & TCP_CONN_FAST_RECOVERY)
441 #define tcp_in_recovery(tc) ((tc)->flags & (TCP_CONN_RECOVERY))
442 #define tcp_in_slowstart(tc) (tc->cwnd < tc->ssthresh)
443 #define tcp_disconnect_pending(tc) ((tc)->flags & TCP_CONN_DCNT_PENDING)
444 #define tcp_disconnect_pending_on(tc) ((tc)->flags |= TCP_CONN_DCNT_PENDING)
445 #define tcp_disconnect_pending_off(tc) ((tc)->flags &= ~TCP_CONN_DCNT_PENDING)
446 #define tcp_fastrecovery_first(tc) ((tc)->flags & TCP_CONN_FRXT_FIRST)
447 #define tcp_fastrecovery_first_on(tc) ((tc)->flags |= TCP_CONN_FRXT_FIRST)
448 #define tcp_fastrecovery_first_off(tc) ((tc)->flags &= ~TCP_CONN_FRXT_FIRST)
450 #define tcp_in_cong_recovery(tc) ((tc)->flags & \
451 (TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY))
454 tcp_cong_recovery_off (tcp_connection_t * tc)
456 tc->flags &= ~(TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY);
457 tcp_fastrecovery_first_off (tc);
460 #define tcp_zero_rwnd_sent(tc) ((tc)->flags & TCP_CONN_ZERO_RWND_SENT)
461 #define tcp_zero_rwnd_sent_on(tc) (tc)->flags |= TCP_CONN_ZERO_RWND_SENT
462 #define tcp_zero_rwnd_sent_off(tc) (tc)->flags &= ~TCP_CONN_ZERO_RWND_SENT
464 typedef enum _tcp_error
466 #define tcp_error(n,s) TCP_ERROR_##n,
467 #include <vnet/tcp/tcp_error.def>
472 typedef struct _tcp_lookup_dispatch
475 } tcp_lookup_dispatch_t;
477 typedef struct tcp_worker_ctx_
479 CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
483 /** worker timer wheel */
484 tw_timer_wheel_16t_2w_512sl_t timer_wheel;
486 /** tx buffer free list */
489 /** tx frames for tcp 4/6 output nodes */
490 vlib_frame_t *tx_frames[2];
492 /** tx frames for ip 4/6 lookup nodes */
493 vlib_frame_t *ip_lookup_tx_frames[2];
495 /** vector of pending ack dequeues */
496 u32 *pending_deq_acked;
498 /** vector of pending disconnect notifications */
499 u32 *pending_disconnects;
501 /** convenience pointer to this thread's vlib main */
504 CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
506 /** cached 'on the wire' options for bursts */
511 typedef struct tcp_iss_seed_
517 typedef struct tcp_configuration_
519 /** Max rx fifo size for a session (in bytes). It is used in to compute the
520 * rfc 7323 window scaling factor */
523 /** Min rx fifo for a session (in bytes) */
526 /** Default MTU to be used when establishing connections */
529 /** Initial CWND multiplier, which multiplies MSS to determine initial CWND.
530 * Set 0 to determine the initial CWND by another way */
531 u16 initial_cwnd_multiplier;
533 /** Enable tx pacing for new connections */
536 /** Default congestion control algorithm type */
537 tcp_cc_algorithm_type_e cc_algo;
539 /** Min rwnd, as number of snd_mss segments, for update ack to be sent after
540 * a zero rwnd advertisement */
541 u32 rwnd_min_update_ack;
543 /** Delayed ack time (disabled) */
546 /** Timer ticks to wait for close from app */
549 /** Timer ticks to wait in time-wait. Also known as 2MSL */
552 /** Timer ticks to wait in fin-wait1 to send fin and rcv fin-ack */
555 /** Timer ticks to wait in last ack for ack */
558 /** Timer ticks to wait in fin-wait2 for fin */
561 /** Timer ticks to wait in closing for fin ack */
564 /** Timer ticks to wait before cleaning up the connection */
567 /** Number of preallocated connections */
568 u32 preallocated_connections;
570 /** Number of preallocated half-open connections */
571 u32 preallocated_half_open_connections;
573 /** Vectors of src addresses. Optional unless one needs > 63K active-opens */
574 ip4_address_t *ip4_src_addrs;
575 ip6_address_t *ip6_src_addrs;
577 /** Fault-injection. Debug only */
578 f64 buffer_fail_fraction;
579 } tcp_configuration_t;
581 typedef struct _tcp_main
583 /* Per-worker thread tcp connection pools */
584 tcp_connection_t **connections;
586 /* Pool of listeners. */
587 tcp_connection_t *listener_pool;
589 /** Dispatch table by state and flags */
590 tcp_lookup_dispatch_t dispatch_table[TCP_N_STATES][64];
592 u8 log2_tstamp_clocks_per_tick;
593 f64 tstamp_ticks_per_clock;
595 /** per-worker context */
596 tcp_worker_ctx_t *wrk_ctx;
598 /** Pool of half-open connections on which we've sent a SYN */
599 tcp_connection_t *half_open_connections;
600 clib_spinlock_t half_open_lock;
602 /** vlib buffer size */
603 u32 bytes_per_buffer;
605 /** Seed used to generate random iss */
606 tcp_iss_seed_t iss_seed;
608 /** Congestion control algorithms registered */
609 tcp_cc_algorithm_t *cc_algos;
611 /** Hash table of cc algorithms by name */
612 uword *cc_algo_by_name;
614 /** Last cc algo registered */
615 tcp_cc_algorithm_type_e cc_last_type;
617 /** Flag that indicates if stack is on or off */
620 /** Flag that indicates if v4 punting is enabled */
623 /** Flag that indicates if v6 punting is enabled */
626 /** Rotor for v4 source addresses */
627 u32 last_v4_addr_rotor;
629 /** Rotor for v6 source addresses */
630 u32 last_v6_addr_rotor;
632 /** Protocol configuration */
633 tcp_configuration_t cfg;
636 extern tcp_main_t tcp_main;
637 extern vlib_node_registration_t tcp4_input_node;
638 extern vlib_node_registration_t tcp6_input_node;
639 extern vlib_node_registration_t tcp4_output_node;
640 extern vlib_node_registration_t tcp6_output_node;
641 extern vlib_node_registration_t tcp4_established_node;
642 extern vlib_node_registration_t tcp6_established_node;
643 extern vlib_node_registration_t tcp4_syn_sent_node;
644 extern vlib_node_registration_t tcp6_syn_sent_node;
645 extern vlib_node_registration_t tcp4_rcv_process_node;
646 extern vlib_node_registration_t tcp6_rcv_process_node;
647 extern vlib_node_registration_t tcp4_listen_node;
648 extern vlib_node_registration_t tcp6_listen_node;
650 #define tcp_cfg tcp_main.cfg
651 #define tcp_node_index(node_id, is_ip4) \
652 ((is_ip4) ? tcp4_##node_id##_node.index : tcp6_##node_id##_node.index)
654 always_inline tcp_main_t *
660 always_inline tcp_worker_ctx_t *
661 tcp_get_worker (u32 thread_index)
663 return &tcp_main.wrk_ctx[thread_index];
666 always_inline tcp_header_t *
667 tcp_buffer_hdr (vlib_buffer_t * b)
669 ASSERT ((signed) b->current_data >= (signed) -VLIB_BUFFER_PRE_DATA_SIZE);
670 return (tcp_header_t *) (b->data + b->current_data
671 + vnet_buffer (b)->tcp.hdr_offset);
674 #if (VLIB_BUFFER_TRACE_TRAJECTORY)
675 #define tcp_trajectory_add_start(b, start) \
677 (*vlib_buffer_trace_trajectory_cb) (b, start); \
680 #define tcp_trajectory_add_start(b, start)
683 clib_error_t *vnet_tcp_enable_disable (vlib_main_t * vm, u8 is_en);
685 void tcp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add);
687 always_inline tcp_connection_t *
688 tcp_connection_get (u32 conn_index, u32 thread_index)
691 (pool_is_free_index (tcp_main.connections[thread_index], conn_index)))
693 return pool_elt_at_index (tcp_main.connections[thread_index], conn_index);
696 always_inline tcp_connection_t *
697 tcp_connection_get_if_valid (u32 conn_index, u32 thread_index)
699 if (tcp_main.connections[thread_index] == 0)
701 if (pool_is_free_index (tcp_main.connections[thread_index], conn_index))
703 return pool_elt_at_index (tcp_main.connections[thread_index], conn_index);
706 always_inline tcp_connection_t *
707 tcp_get_connection_from_transport (transport_connection_t * tconn)
709 return (tcp_connection_t *) tconn;
713 tcp_connection_set_state (tcp_connection_t * tc, tcp_state_t state)
716 TCP_EVT (TCP_EVT_STATE_CHANGE, tc);
719 void tcp_connection_close (tcp_connection_t * tc);
720 void tcp_connection_cleanup (tcp_connection_t * tc);
721 void tcp_connection_del (tcp_connection_t * tc);
722 int tcp_half_open_connection_cleanup (tcp_connection_t * tc);
723 tcp_connection_t *tcp_connection_alloc (u8 thread_index);
724 tcp_connection_t *tcp_connection_alloc_w_base (u8 thread_index,
725 tcp_connection_t * base);
726 void tcp_connection_free (tcp_connection_t * tc);
727 void tcp_connection_reset (tcp_connection_t * tc);
728 int tcp_configure_v4_source_address_range (vlib_main_t * vm,
729 ip4_address_t * start,
730 ip4_address_t * end, u32 table_id);
731 int tcp_configure_v6_source_address_range (vlib_main_t * vm,
732 ip6_address_t * start,
733 ip6_address_t * end, u32 table_id);
734 void tcp_api_reference (void);
735 u8 *format_tcp_connection (u8 * s, va_list * args);
737 always_inline tcp_connection_t *
738 tcp_listener_get (u32 tli)
740 return pool_elt_at_index (tcp_main.listener_pool, tli);
743 always_inline tcp_connection_t *
744 tcp_half_open_connection_get (u32 conn_index)
746 tcp_connection_t *tc = 0;
747 clib_spinlock_lock_if_init (&tcp_main.half_open_lock);
748 if (!pool_is_free_index (tcp_main.half_open_connections, conn_index))
749 tc = pool_elt_at_index (tcp_main.half_open_connections, conn_index);
750 clib_spinlock_unlock_if_init (&tcp_main.half_open_lock);
754 void tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b);
755 void tcp_make_synack (tcp_connection_t * ts, vlib_buffer_t * b);
756 void tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
757 u32 thread_index, u8 is_ip4);
758 void tcp_send_reset (tcp_connection_t * tc);
759 void tcp_send_syn (tcp_connection_t * tc);
760 void tcp_send_synack (tcp_connection_t * tc);
761 void tcp_send_fin (tcp_connection_t * tc);
762 void tcp_update_burst_snd_vars (tcp_connection_t * tc);
763 void tcp_update_rto (tcp_connection_t * tc);
764 void tcp_flush_frame_to_output (tcp_worker_ctx_t * wrk, u8 is_ip4);
765 void tcp_flush_frames_to_output (tcp_worker_ctx_t * wrk);
766 void tcp_send_window_update_ack (tcp_connection_t * tc);
768 void tcp_program_ack (tcp_connection_t * tc);
769 void tcp_program_dupack (tcp_connection_t * tc);
770 void tcp_program_retransmit (tcp_connection_t * tc);
777 * Byte tracker initialize
779 * @param tc connection for which the byte tracker should be allocated and
782 void tcp_bt_init (tcp_connection_t * tc);
784 * Byte tracker cleanup
786 * @param tc connection for which the byte tracker should be cleaned up
788 void tcp_bt_cleanup (tcp_connection_t * tc);
790 * Flush byte tracker samples
792 * @param tc tcp connection for which samples should be flushed
794 void tcp_bt_flush_samples (tcp_connection_t * tc);
796 * Track a tcp tx burst
798 * @param tc tcp connection
800 void tcp_bt_track_tx (tcp_connection_t * tc);
802 * Track a tcp retransmission
804 * @param tc tcp connection
805 * @param start start sequence number
806 * @param end end sequence number
808 void tcp_bt_track_rxt (tcp_connection_t * tc, u32 start, u32 end);
810 * Generate a delivery rate sample from recently acked bytes
812 * @param tc tcp connection
813 * @param rs resulting rate sample
815 void tcp_bt_sample_delivery_rate (tcp_connection_t * tc,
816 tcp_rate_sample_t * rs);
818 * Check if sample to be generated is app limited
820 * @param tc tcp connection
822 void tcp_bt_check_app_limited (tcp_connection_t * tc);
824 * Check if the byte tracker is in sane state
826 * Should be used only for testing
828 * @param bt byte tracker
830 int tcp_bt_is_sane (tcp_byte_tracker_t * bt);
833 tcp_end_seq (tcp_header_t * th, u32 len)
835 return th->seq_number + tcp_is_syn (th) + tcp_is_fin (th) + len;
838 /* Modulo arithmetic for TCP sequence numbers */
839 #define seq_lt(_s1, _s2) ((i32)((_s1)-(_s2)) < 0)
840 #define seq_leq(_s1, _s2) ((i32)((_s1)-(_s2)) <= 0)
841 #define seq_gt(_s1, _s2) ((i32)((_s1)-(_s2)) > 0)
842 #define seq_geq(_s1, _s2) ((i32)((_s1)-(_s2)) >= 0)
843 #define seq_max(_s1, _s2) (seq_gt((_s1), (_s2)) ? (_s1) : (_s2))
845 /* Modulo arithmetic for timestamps */
846 #define timestamp_lt(_t1, _t2) ((i32)((_t1)-(_t2)) < 0)
847 #define timestamp_leq(_t1, _t2) ((i32)((_t1)-(_t2)) <= 0)
850 * Our estimate of the number of bytes that have left the network
853 tcp_bytes_out (const tcp_connection_t * tc)
855 if (tcp_opts_sack_permitted (&tc->rcv_opts))
856 return tc->sack_sb.sacked_bytes + tc->sack_sb.lost_bytes;
858 return tc->rcv_dupacks * tc->snd_mss;
862 * Our estimate of the number of bytes in flight (pipe size)
865 tcp_flight_size (const tcp_connection_t * tc)
869 flight_size = (int) (tc->snd_nxt - tc->snd_una) - tcp_bytes_out (tc)
870 + tc->snd_rxt_bytes - tc->rxt_delivered;
872 ASSERT (flight_size >= 0);
878 * Initial cwnd as per RFC5681
881 tcp_initial_cwnd (const tcp_connection_t * tc)
883 if (tcp_cfg.initial_cwnd_multiplier > 0)
884 return tcp_cfg.initial_cwnd_multiplier * tc->snd_mss;
886 if (tc->snd_mss > 2190)
887 return 2 * tc->snd_mss;
888 else if (tc->snd_mss > 1095)
889 return 3 * tc->snd_mss;
891 return 4 * tc->snd_mss;
895 * Accumulate acked bytes for cwnd increase
897 * Once threshold bytes are accumulated, snd_mss bytes are added
901 tcp_cwnd_accumulate (tcp_connection_t * tc, u32 thresh, u32 bytes)
903 tc->cwnd_acc_bytes += bytes;
904 if (tc->cwnd_acc_bytes >= thresh)
906 u32 inc = tc->cwnd_acc_bytes / thresh;
907 tc->cwnd_acc_bytes -= inc * thresh;
908 tc->cwnd += inc * tc->snd_mss;
909 tc->cwnd = clib_min (tc->cwnd, tc->tx_fifo_size);
914 tcp_loss_wnd (const tcp_connection_t * tc)
916 /* Whatever we have in flight + the packet we're about to send */
917 return tcp_flight_size (tc) + tc->snd_mss;
921 tcp_available_snd_wnd (const tcp_connection_t * tc)
923 return clib_min (tc->cwnd, tc->snd_wnd);
927 tcp_available_output_snd_space (const tcp_connection_t * tc)
929 u32 available_wnd = tcp_available_snd_wnd (tc);
930 int flight_size = (int) (tc->snd_nxt - tc->snd_una);
932 if (available_wnd <= flight_size)
935 return available_wnd - flight_size;
939 * Estimate of how many bytes we can still push into the network
942 tcp_available_cc_snd_space (const tcp_connection_t * tc)
944 u32 available_wnd = tcp_available_snd_wnd (tc);
945 u32 flight_size = tcp_flight_size (tc);
947 if (available_wnd <= flight_size)
950 return available_wnd - flight_size;
954 tcp_is_lost_fin (tcp_connection_t * tc)
956 if ((tc->flags & TCP_CONN_FINSNT) && (tc->snd_una_max - tc->snd_una == 1))
961 u32 tcp_snd_space (tcp_connection_t * tc);
962 int tcp_fastrecovery_prr_snd_space (tcp_connection_t * tc);
964 fib_node_index_t tcp_lookup_rmt_in_fib (tcp_connection_t * tc);
966 /* Made public for unit testing only */
967 void tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end);
968 u32 tcp_sack_list_bytes (tcp_connection_t * tc);
973 return tcp_main.wrk_ctx[vlib_get_thread_index ()].time_now;
977 tcp_time_now_w_thread (u32 thread_index)
979 return tcp_main.wrk_ctx[thread_index].time_now;
983 * Generate timestamp for tcp connection
986 tcp_tstamp (tcp_connection_t * tc)
988 return (tcp_main.wrk_ctx[tc->c_thread_index].time_now -
989 tc->timestamp_delta);
993 tcp_time_now_us (u32 thread_index)
995 return transport_time_now (thread_index);
999 tcp_set_time_now (tcp_worker_ctx_t * wrk)
1001 wrk->time_now = clib_cpu_time_now () * tcp_main.tstamp_ticks_per_clock;
1002 return wrk->time_now;
1005 u32 tcp_session_push_header (transport_connection_t * tconn,
1007 int tcp_session_custom_tx (void *conn, u32 max_burst_size);
1009 void tcp_connection_timers_init (tcp_connection_t * tc);
1010 void tcp_connection_timers_reset (tcp_connection_t * tc);
1011 void tcp_init_snd_vars (tcp_connection_t * tc);
1012 void tcp_connection_init_vars (tcp_connection_t * tc);
1013 void tcp_connection_tx_pacer_update (tcp_connection_t * tc);
1014 void tcp_connection_tx_pacer_reset (tcp_connection_t * tc, u32 window,
1018 tcp_cc_rcv_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
1020 tc->cc_algo->rcv_ack (tc, rs);
1021 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
1025 tcp_cc_rcv_cong_ack (tcp_connection_t * tc, tcp_cc_ack_t ack_type,
1026 tcp_rate_sample_t * rs)
1028 tc->cc_algo->rcv_cong_ack (tc, ack_type, rs);
1032 tcp_cc_congestion (tcp_connection_t * tc)
1034 tc->cc_algo->congestion (tc);
1038 tcp_cc_loss (tcp_connection_t * tc)
1040 tc->cc_algo->loss (tc);
1044 tcp_cc_recovered (tcp_connection_t * tc)
1046 tc->cc_algo->recovered (tc);
1050 tcp_cc_undo_recovery (tcp_connection_t * tc)
1052 if (tc->cc_algo->undo_recovery)
1053 tc->cc_algo->undo_recovery (tc);
1057 tcp_cc_event (tcp_connection_t * tc, tcp_cc_event_t evt)
1059 if (tc->cc_algo->event)
1060 tc->cc_algo->event (tc, evt);
1064 tcp_cc_get_pacing_rate (tcp_connection_t * tc)
1066 if (tc->cc_algo->get_pacing_rate)
1067 return tc->cc_algo->get_pacing_rate (tc);
1069 f64 srtt = clib_min ((f64) tc->srtt * TCP_TICK, tc->mrtt_us);
1071 /* TODO should constrain to interface's max throughput but
1072 * we don't have link speeds for sw ifs ..*/
1073 return ((f64) tc->cwnd / srtt);
1077 tcp_timer_set (tcp_connection_t * tc, u8 timer_id, u32 interval)
1079 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
1080 ASSERT (tc->timers[timer_id] == TCP_TIMER_HANDLE_INVALID);
1081 tc->timers[timer_id] =
1082 tw_timer_start_16t_2w_512sl (&tcp_main.
1083 wrk_ctx[tc->c_thread_index].timer_wheel,
1084 tc->c_c_index, timer_id, interval);
1088 tcp_timer_reset (tcp_connection_t * tc, u8 timer_id)
1090 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
1091 if (tc->timers[timer_id] == TCP_TIMER_HANDLE_INVALID)
1094 tw_timer_stop_16t_2w_512sl (&tcp_main.
1095 wrk_ctx[tc->c_thread_index].timer_wheel,
1096 tc->timers[timer_id]);
1097 tc->timers[timer_id] = TCP_TIMER_HANDLE_INVALID;
1101 tcp_timer_update (tcp_connection_t * tc, u8 timer_id, u32 interval)
1103 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
1104 if (tc->timers[timer_id] != TCP_TIMER_HANDLE_INVALID)
1105 tw_timer_update_16t_2w_512sl (&tcp_main.
1106 wrk_ctx[tc->c_thread_index].timer_wheel,
1107 tc->timers[timer_id], interval);
1109 tc->timers[timer_id] =
1110 tw_timer_start_16t_2w_512sl (&tcp_main.
1111 wrk_ctx[tc->c_thread_index].timer_wheel,
1112 tc->c_c_index, timer_id, interval);
1116 tcp_retransmit_timer_set (tcp_connection_t * tc)
1118 ASSERT (tc->snd_una != tc->snd_una_max);
1119 tcp_timer_set (tc, TCP_TIMER_RETRANSMIT,
1120 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1124 tcp_retransmit_timer_reset (tcp_connection_t * tc)
1126 tcp_timer_reset (tc, TCP_TIMER_RETRANSMIT);
1130 tcp_retransmit_timer_force_update (tcp_connection_t * tc)
1132 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
1133 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1137 tcp_persist_timer_set (tcp_connection_t * tc)
1139 /* Reuse RTO. It's backed off in handler */
1140 tcp_timer_set (tc, TCP_TIMER_PERSIST,
1141 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1145 tcp_persist_timer_update (tcp_connection_t * tc)
1147 tcp_timer_update (tc, TCP_TIMER_PERSIST,
1148 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1152 tcp_persist_timer_reset (tcp_connection_t * tc)
1154 tcp_timer_reset (tc, TCP_TIMER_PERSIST);
1158 tcp_retransmit_timer_update (tcp_connection_t * tc)
1160 if (tc->snd_una == tc->snd_nxt)
1162 tcp_retransmit_timer_reset (tc);
1163 if (tc->snd_wnd < tc->snd_mss)
1164 tcp_persist_timer_update (tc);
1167 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
1168 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1172 tcp_timer_is_active (tcp_connection_t * tc, tcp_timers_e timer)
1174 return tc->timers[timer] != TCP_TIMER_HANDLE_INVALID;
1177 #define tcp_validate_txf_size(_tc, _a) \
1178 ASSERT(_tc->state != TCP_STATE_ESTABLISHED \
1179 || transport_max_tx_dequeue (&_tc->connection) >= _a)
1181 void tcp_rcv_sacks (tcp_connection_t * tc, u32 ack);
1182 u8 *tcp_scoreboard_replay (u8 * s, tcp_connection_t * tc, u8 verbose);
1185 * Register exiting cc algo type
1187 void tcp_cc_algo_register (tcp_cc_algorithm_type_e type,
1188 const tcp_cc_algorithm_t * vft);
1191 * Register new cc algo type
1193 tcp_cc_algorithm_type_e tcp_cc_algo_new_type (const tcp_cc_algorithm_t * vft);
1194 tcp_cc_algorithm_t *tcp_cc_algo_get (tcp_cc_algorithm_type_e type);
1196 static inline void *
1197 tcp_cc_data (tcp_connection_t * tc)
1199 return (void *) tc->cc_data;
1202 void newreno_rcv_cong_ack (tcp_connection_t * tc, tcp_cc_ack_t ack_type,
1203 tcp_rate_sample_t * rs);
1206 * Push TCP header to buffer
1208 * @param vm - vlib_main
1209 * @param b - buffer to write the header to
1210 * @param sp_net - source port net order
1211 * @param dp_net - destination port net order
1212 * @param seq - sequence number net order
1213 * @param ack - ack number net order
1214 * @param tcp_hdr_opts_len - header and options length in bytes
1215 * @param flags - header flags
1216 * @param wnd - window size
1218 * @return - pointer to start of TCP header
1220 always_inline void *
1221 vlib_buffer_push_tcp_net_order (vlib_buffer_t * b, u16 sp, u16 dp, u32 seq,
1222 u32 ack, u8 tcp_hdr_opts_len, u8 flags,
1227 th = vlib_buffer_push_uninit (b, tcp_hdr_opts_len);
1231 th->seq_number = seq;
1232 th->ack_number = ack;
1233 th->data_offset_and_reserved = (tcp_hdr_opts_len >> 2) << 4;
1237 th->urgent_pointer = 0;
1238 vnet_buffer (b)->l4_hdr_offset = (u8 *) th - b->data;
1239 b->flags |= VNET_BUFFER_F_L4_HDR_OFFSET_VALID;
1244 * Push TCP header to buffer
1246 * @param b - buffer to write the header to
1247 * @param sp_net - source port net order
1248 * @param dp_net - destination port net order
1249 * @param seq - sequence number host order
1250 * @param ack - ack number host order
1251 * @param tcp_hdr_opts_len - header and options length in bytes
1252 * @param flags - header flags
1253 * @param wnd - window size
1255 * @return - pointer to start of TCP header
1257 always_inline void *
1258 vlib_buffer_push_tcp (vlib_buffer_t * b, u16 sp_net, u16 dp_net, u32 seq,
1259 u32 ack, u8 tcp_hdr_opts_len, u8 flags, u16 wnd)
1261 return vlib_buffer_push_tcp_net_order (b, sp_net, dp_net,
1262 clib_host_to_net_u32 (seq),
1263 clib_host_to_net_u32 (ack),
1264 tcp_hdr_opts_len, flags,
1265 clib_host_to_net_u16 (wnd));
1268 #endif /* _vnet_tcp_h_ */
1271 * fd.io coding-style-patch-verification: ON
1274 * eval: (c-set-style "gnu")