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
35 #define TCP_DUPACK_THRESHOLD 3
36 #define TCP_IW_N_SEGMENTS 10
37 #define TCP_ALWAYS_ACK 1 /**< On/off delayed acks */
38 #define TCP_USE_SACKS 1 /**< Disable only for testing */
40 /** TCP FSM state definitions as per RFC793. */
41 #define foreach_tcp_fsm_state \
44 _(SYN_SENT, "SYN_SENT") \
45 _(SYN_RCVD, "SYN_RCVD") \
46 _(ESTABLISHED, "ESTABLISHED") \
47 _(CLOSE_WAIT, "CLOSE_WAIT") \
48 _(FIN_WAIT_1, "FIN_WAIT_1") \
49 _(LAST_ACK, "LAST_ACK") \
50 _(CLOSING, "CLOSING") \
51 _(FIN_WAIT_2, "FIN_WAIT_2") \
52 _(TIME_WAIT, "TIME_WAIT")
54 typedef enum _tcp_state
56 #define _(sym, str) TCP_STATE_##sym,
62 format_function_t format_tcp_state;
63 format_function_t format_tcp_flags;
64 format_function_t format_tcp_sacks;
65 format_function_t format_tcp_rcv_sacks;
68 #define foreach_tcp_timer \
69 _(RETRANSMIT, "RETRANSMIT") \
70 _(DELACK, "DELAYED ACK") \
71 _(PERSIST, "PERSIST") \
72 _(WAITCLOSE, "WAIT CLOSE") \
73 _(RETRANSMIT_SYN, "RETRANSMIT SYN") \
75 typedef enum _tcp_timers
77 #define _(sym, str) TCP_TIMER_##sym,
83 typedef void (timer_expiration_handler) (u32 index);
85 extern timer_expiration_handler tcp_timer_delack_handler;
86 extern timer_expiration_handler tcp_timer_retransmit_handler;
87 extern timer_expiration_handler tcp_timer_persist_handler;
88 extern timer_expiration_handler tcp_timer_retransmit_syn_handler;
90 #define TCP_TIMER_HANDLE_INVALID ((u32) ~0)
92 #define TCP_TIMER_TICK 0.1 /**< Timer tick in seconds */
93 #define TCP_TO_TIMER_TICK TCP_TICK*10 /**< Factor for converting
94 ticks to timer ticks */
96 #define TCP_RTO_MAX 60 * THZ /* Min max RTO (60s) as per RFC6298 */
97 #define TCP_RTO_MIN 0.2 * THZ /* Min RTO (200ms) - lower than standard */
98 #define TCP_RTT_MAX 30 * THZ /* 30s (probably too much) */
99 #define TCP_RTO_SYN_RETRIES 3 /* SYN retries without doubling RTO */
100 #define TCP_RTO_INIT 1 * THZ /* Initial retransmit timer */
101 #define TCP_RTO_BOFF_MAX 8 /* Max number of retries before reset */
102 #define TCP_ESTABLISH_TIME (60 * THZ) /* Connection establish timeout */
104 /** TCP connection flags */
105 #define foreach_tcp_connection_flag \
106 _(SNDACK, "Send ACK") \
107 _(FINSNT, "FIN sent") \
108 _(RECOVERY, "Recovery") \
109 _(FAST_RECOVERY, "Fast Recovery") \
110 _(DCNT_PENDING, "Disconnect pending") \
111 _(HALF_OPEN_DONE, "Half-open completed") \
112 _(FINPNDG, "FIN pending") \
113 _(FRXT_PENDING, "Fast-retransmit pending") \
114 _(FRXT_FIRST, "Fast-retransmit first again") \
115 _(DEQ_PENDING, "Pending dequeue acked") \
116 _(PSH_PENDING, "PSH pending") \
117 _(FINRCVD, "FIN received") \
118 _(RATE_SAMPLE, "Conn does rate sampling") \
119 _(TRACK_BURST, "Track burst") \
120 _(ZERO_RWND_SENT, "Zero RWND sent") \
122 typedef enum _tcp_connection_flag_bits
124 #define _(sym, str) TCP_CONN_##sym##_BIT,
125 foreach_tcp_connection_flag
128 } tcp_connection_flag_bits_e;
130 typedef enum _tcp_connection_flag
132 #define _(sym, str) TCP_CONN_##sym = 1 << TCP_CONN_##sym##_BIT,
133 foreach_tcp_connection_flag
136 } tcp_connection_flags_e;
138 #define TCP_SCOREBOARD_TRACE (0)
139 #define TCP_MAX_SACK_BLOCKS 256 /**< Max number of SACK blocks stored */
140 #define TCP_INVALID_SACK_HOLE_INDEX ((u32)~0)
142 typedef struct _scoreboard_trace_elt
149 } scoreboard_trace_elt_t;
151 typedef struct _sack_scoreboard_hole
153 u32 next; /**< Index for next entry in linked list */
154 u32 prev; /**< Index for previous entry in linked list */
155 u32 start; /**< Start sequence number */
156 u32 end; /**< End sequence number */
157 u8 is_lost; /**< Mark hole as lost */
158 } sack_scoreboard_hole_t;
160 typedef struct _sack_scoreboard
162 sack_scoreboard_hole_t *holes; /**< Pool of holes */
163 u32 head; /**< Index of first entry */
164 u32 tail; /**< Index of last entry */
165 u32 sacked_bytes; /**< Number of bytes sacked in sb */
166 u32 last_sacked_bytes; /**< Number of bytes last sacked */
167 u32 last_bytes_delivered; /**< Sack bytes delivered to app */
168 u32 snd_una_adv; /**< Bytes to add to snd_una */
169 u32 high_sacked; /**< Highest byte sacked (fack) */
170 u32 high_rxt; /**< Highest retransmitted sequence */
171 u32 rescue_rxt; /**< Rescue sequence number */
172 u32 lost_bytes; /**< Bytes lost as per RFC6675 */
173 u32 last_lost_bytes; /**< Number of bytes last lost */
174 u32 cur_rxt_hole; /**< Retransmitting from this hole */
176 #if TCP_SCOREBOARD_TRACE
177 scoreboard_trace_elt_t *trace;
182 #if TCP_SCOREBOARD_TRACE
183 #define tcp_scoreboard_trace_add(_tc, _ack) \
185 static u64 _group = 0; \
186 sack_scoreboard_t *_sb = &_tc->sack_sb; \
187 sack_block_t *_sack, *_sacks; \
188 scoreboard_trace_elt_t *_elt; \
191 _sacks = _tc->rcv_opts.sacks; \
192 for (i = 0; i < vec_len (_sacks); i++) \
194 _sack = &_sacks[i]; \
195 vec_add2 (_sb->trace, _elt, 1); \
196 _elt->start = _sack->start; \
197 _elt->end = _sack->end; \
198 _elt->ack = _elt->end == _ack ? _ack : 0; \
199 _elt->snd_una_max = _elt->end == _ack ? _tc->snd_una_max : 0; \
200 _elt->group = _group; \
204 #define tcp_scoreboard_trace_add(_tc, _ack)
207 sack_scoreboard_hole_t *scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
208 sack_scoreboard_hole_t *
209 start, u8 have_sent_1_smss,
212 sack_scoreboard_hole_t *scoreboard_get_hole (sack_scoreboard_t * sb,
215 sack_scoreboard_hole_t *scoreboard_next_hole (sack_scoreboard_t * sb,
216 sack_scoreboard_hole_t * hole);
217 sack_scoreboard_hole_t *scoreboard_prev_hole (sack_scoreboard_t * sb,
218 sack_scoreboard_hole_t * hole);
219 sack_scoreboard_hole_t *scoreboard_first_hole (sack_scoreboard_t * sb);
220 sack_scoreboard_hole_t *scoreboard_last_hole (sack_scoreboard_t * sb);
221 void scoreboard_clear (sack_scoreboard_t * sb);
222 void scoreboard_init (sack_scoreboard_t * sb);
223 u8 *format_tcp_scoreboard (u8 * s, va_list * args);
225 #define TCP_BTS_INVALID_INDEX ((u32)~0)
227 typedef enum tcp_bts_flags_
230 TCP_BTS_IS_APP_LIMITED = 1 << 1,
231 } __clib_packed tcp_bts_flags_t;
233 typedef struct tcp_bt_sample_
235 u32 next; /**< Next sample index in list */
236 u32 prev; /**< Previous sample index in list */
237 u32 min_seq; /**< Min seq number in sample */
238 u32 max_seq; /**< Max seq number. Set for rxt samples */
239 u64 delivered; /**< Total delivered bytes for sample */
240 f64 delivered_time; /**< Delivered time when sample taken */
241 f64 tx_time; /**< Transmit time for the burst */
242 u64 tx_rate; /**< Tx pacing rate */
243 tcp_bts_flags_t flags; /**< Sample flag */
246 typedef struct tcp_rate_sample_
248 u64 prior_delivered; /**< Delivered of sample used for rate, i.e.,
249 total bytes delivered at prior_time */
250 f64 prior_time; /**< Delivered time of sample used for rate */
251 f64 interval_time; /**< Time to ack the bytes delivered */
252 f64 rtt_time; /**< RTT for sample */
253 u64 tx_rate; /**< Tx pacing rate */
254 u32 delivered; /**< Bytes delivered in interval_time */
255 u32 acked_and_sacked; /**< Bytes acked + sacked now */
256 u32 lost; /**< Bytes lost now */
257 tcp_bts_flags_t flags; /**< Rate sample flags from bt sample */
260 typedef struct tcp_byte_tracker_
262 tcp_bt_sample_t *samples; /**< Pool of samples */
263 rb_tree_t sample_lookup; /**< Rbtree for sample lookup by min_seq */
264 u32 head; /**< Head of samples linked list */
265 u32 tail; /**< Tail of samples linked list */
266 u32 last_ooo; /**< Cached last ooo sample */
267 } tcp_byte_tracker_t;
269 typedef enum _tcp_cc_algorithm_type
273 TCP_CC_LAST = TCP_CC_CUBIC
274 } tcp_cc_algorithm_type_e;
276 typedef struct _tcp_cc_algorithm tcp_cc_algorithm_t;
278 typedef enum _tcp_cc_ack_t
285 typedef enum tcp_cc_event_
291 * As per RFC4898 tcpEStatsStackSoftErrors
293 typedef struct tcp_errors_
295 u32 below_data_wnd; /**< All data in seg is below snd_una */
296 u32 above_data_wnd; /**< Some data in segment is above snd_wnd */
297 u32 below_ack_wnd; /**< Acks for data below snd_una */
298 u32 above_ack_wnd; /**< Acks for data not sent */
301 typedef struct _tcp_connection
303 CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
304 transport_connection_t connection; /**< Common transport data. First! */
306 u8 state; /**< TCP state as per tcp_state_t */
307 u16 flags; /**< Connection flags (see tcp_conn_flags_e) */
308 u32 timers[TCP_N_TIMERS]; /**< Timer handles into timer wheel */
310 u64 segs_in; /** RFC4022/4898 tcpHCInSegs/tcpEStatsPerfSegsIn */
311 u64 bytes_in; /** RFC4898 tcpEStatsPerfHCDataOctetsIn */
312 u64 segs_out; /** RFC4898 tcpEStatsPerfSegsOut */
313 u64 bytes_out; /** RFC4898 tcpEStatsPerfHCDataOctetsOut */
315 /** Send sequence variables RFC793 */
316 u32 snd_una; /**< oldest unacknowledged sequence number */
317 u32 snd_una_max; /**< newest unacknowledged sequence number + 1*/
318 u32 snd_wnd; /**< send window */
319 u32 snd_wl1; /**< seq number used for last snd.wnd update */
320 u32 snd_wl2; /**< ack number used for last snd.wnd update */
321 u32 snd_nxt; /**< next seq number to be sent */
322 u16 snd_mss; /**< Effective send max seg (data) size */
324 u64 data_segs_in; /** RFC4898 tcpEStatsPerfDataSegsIn */
325 u64 data_segs_out; /** RFC4898 tcpEStatsPerfDataSegsOut */
327 /** Receive sequence variables RFC793 */
328 u32 rcv_nxt; /**< next sequence number expected */
329 u32 rcv_wnd; /**< receive window we expect */
331 u32 rcv_las; /**< rcv_nxt at last ack sent/rcv_wnd update */
332 u32 iss; /**< initial sent sequence */
333 u32 irs; /**< initial remote sequence */
336 u8 snd_opts_len; /**< Tx options len */
337 u8 rcv_wscale; /**< Window scale to advertise to peer */
338 u8 snd_wscale; /**< Window scale to use when sending */
339 u32 tsval_recent; /**< Last timestamp received */
340 u32 tsval_recent_age; /**< When last updated tstamp_recent*/
341 tcp_options_t snd_opts; /**< Tx options for connection */
342 tcp_options_t rcv_opts; /**< Rx options for connection */
344 sack_block_t *snd_sacks; /**< Vector of SACKs to send. XXX Fixed size? */
345 u8 snd_sack_pos; /**< Position in vec of first block to send */
346 sack_block_t *snd_sacks_fl; /**< Vector for building new list */
347 sack_scoreboard_t sack_sb; /**< SACK "scoreboard" that tracks holes */
349 u16 rcv_dupacks; /**< Number of recent DUPACKs received */
350 u32 dupacks_in; /**< RFC4898 tcpEStatsStackDupAcksIn*/
351 u8 pending_dupacks; /**< Number of DUPACKs to be sent */
352 u32 dupacks_out; /**< RFC4898 tcpEStatsPathDupAcksOut */
354 /* Congestion control */
355 u32 cwnd; /**< Congestion window */
356 u32 cwnd_acc_bytes; /**< Bytes accumulated for cwnd increment */
357 u32 ssthresh; /**< Slow-start threshold */
358 u32 prev_ssthresh; /**< ssthresh before congestion */
359 u32 prev_cwnd; /**< ssthresh before congestion */
360 u32 bytes_acked; /**< Bytes acknowledged by current segment */
361 u32 burst_acked; /**< Bytes acknowledged in current burst */
362 u32 snd_rxt_bytes; /**< Retransmitted bytes */
363 u32 snd_rxt_ts; /**< Timestamp when first packet is retransmitted */
364 u32 tsecr_last_ack; /**< Timestamp echoed to us in last healthy ACK */
365 u32 snd_congestion; /**< snd_una_max when congestion is detected */
366 u32 tx_fifo_size; /**< Tx fifo size. Used to constrain cwnd */
367 tcp_cc_algorithm_t *cc_algo; /**< Congestion control algorithm */
368 u8 cc_data[TCP_CC_DATA_SZ]; /**< Congestion control algo private data */
370 u32 fr_occurences; /**< fast-retransmit occurrences RFC4898
371 tcpEStatsStackFastRetran */
372 u32 tr_occurences; /**< timer-retransmit occurrences */
373 u64 bytes_retrans; /**< RFC4898 tcpEStatsPerfOctetsRetrans */
374 u64 segs_retrans; /**< RFC4898 tcpEStatsPerfSegsRetrans*/
377 u32 rto; /**< Retransmission timeout */
378 u32 rto_boff; /**< Index for RTO backoff */
379 u32 srtt; /**< Smoothed RTT */
380 u32 rttvar; /**< Smoothed mean RTT difference. Approximates variance */
381 u32 rtt_seq; /**< Sequence number for tracked ACK */
382 f64 rtt_ts; /**< Timestamp for tracked ACK */
383 f64 mrtt_us; /**< High precision mrtt from tracked acks */
385 u32 psh_seq; /**< Add psh header for seg that includes this */
386 u32 next_node_index; /**< Can be used to control next node in output */
387 u32 next_node_opaque; /**< Opaque to pass to next node */
388 u32 limited_transmit; /**< snd_nxt when limited transmit starts */
389 u32 sw_if_index; /**< Interface for the connection */
391 /* Delivery rate estimation */
392 u64 delivered; /**< Total bytes delivered to peer */
393 u64 app_limited; /**< Delivered when app-limited detected */
394 f64 delivered_time; /**< Time last bytes were acked */
395 tcp_byte_tracker_t *bt; /**< Tx byte tracker */
397 tcp_errors_t errors; /**< Soft connection errors */
399 f64 start_ts; /**< Timestamp when connection initialized */
400 u32 last_fib_check; /**< Last time we checked fib route for peer */
401 u16 mss; /**< Our max seg size that includes options */
402 u32 timestamp_delta; /**< Offset for timestamp */
406 struct _tcp_cc_algorithm
409 uword (*unformat_cfg) (unformat_input_t * input);
410 void (*init) (tcp_connection_t * tc);
411 void (*cleanup) (tcp_connection_t * tc);
412 void (*rcv_ack) (tcp_connection_t * tc, tcp_rate_sample_t *rs);
413 void (*rcv_cong_ack) (tcp_connection_t * tc, tcp_cc_ack_t ack,
414 tcp_rate_sample_t *rs);
415 void (*congestion) (tcp_connection_t * tc);
416 void (*loss) (tcp_connection_t * tc);
417 void (*recovered) (tcp_connection_t * tc);
418 void (*undo_recovery) (tcp_connection_t * tc);
419 void (*event) (tcp_connection_t *tc, tcp_cc_event_t evt);
423 #define tcp_fastrecovery_on(tc) (tc)->flags |= TCP_CONN_FAST_RECOVERY
424 #define tcp_fastrecovery_off(tc) (tc)->flags &= ~TCP_CONN_FAST_RECOVERY
425 #define tcp_recovery_on(tc) (tc)->flags |= TCP_CONN_RECOVERY
426 #define tcp_recovery_off(tc) (tc)->flags &= ~TCP_CONN_RECOVERY
427 #define tcp_in_fastrecovery(tc) ((tc)->flags & TCP_CONN_FAST_RECOVERY)
428 #define tcp_in_recovery(tc) ((tc)->flags & (TCP_CONN_RECOVERY))
429 #define tcp_in_slowstart(tc) (tc->cwnd < tc->ssthresh)
430 #define tcp_disconnect_pending(tc) ((tc)->flags & TCP_CONN_DCNT_PENDING)
431 #define tcp_disconnect_pending_on(tc) ((tc)->flags |= TCP_CONN_DCNT_PENDING)
432 #define tcp_disconnect_pending_off(tc) ((tc)->flags &= ~TCP_CONN_DCNT_PENDING)
433 #define tcp_fastrecovery_first(tc) ((tc)->flags & TCP_CONN_FRXT_FIRST)
434 #define tcp_fastrecovery_first_on(tc) ((tc)->flags |= TCP_CONN_FRXT_FIRST)
435 #define tcp_fastrecovery_first_off(tc) ((tc)->flags &= ~TCP_CONN_FRXT_FIRST)
437 #define tcp_in_cong_recovery(tc) ((tc)->flags & \
438 (TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY))
441 tcp_cong_recovery_off (tcp_connection_t * tc)
443 tc->flags &= ~(TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY);
444 tcp_fastrecovery_first_off (tc);
447 #define tcp_zero_rwnd_sent(tc) ((tc)->flags & TCP_CONN_ZERO_RWND_SENT)
448 #define tcp_zero_rwnd_sent_on(tc) (tc)->flags |= TCP_CONN_ZERO_RWND_SENT
449 #define tcp_zero_rwnd_sent_off(tc) (tc)->flags &= ~TCP_CONN_ZERO_RWND_SENT
451 typedef enum _tcp_error
453 #define tcp_error(n,s) TCP_ERROR_##n,
454 #include <vnet/tcp/tcp_error.def>
459 typedef struct _tcp_lookup_dispatch
462 } tcp_lookup_dispatch_t;
464 typedef struct tcp_worker_ctx_
466 CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
470 /** worker timer wheel */
471 tw_timer_wheel_16t_2w_512sl_t timer_wheel;
473 /** tx buffer free list */
476 /** tx frames for tcp 4/6 output nodes */
477 vlib_frame_t *tx_frames[2];
479 /** tx frames for ip 4/6 lookup nodes */
480 vlib_frame_t *ip_lookup_tx_frames[2];
482 /** vector of pending ack dequeues */
483 u32 *pending_deq_acked;
485 /** vector of pending disconnect notifications */
486 u32 *pending_disconnects;
488 /** convenience pointer to this thread's vlib main */
491 CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
493 /** cached 'on the wire' options for bursts */
498 typedef struct tcp_iss_seed_
504 typedef struct tcp_configuration_
506 /** Max rx fifo size for a session (in bytes). It is used in to compute the
507 * rfc 7323 window scaling factor */
510 /** Min rx fifo for a session (in bytes) */
513 /** Default MTU to be used when establishing connections */
516 /** Initial CWND multiplier, which multiplies MSS to determine initial CWND.
517 * Set 0 to determine the initial CWND by another way */
518 u16 initial_cwnd_multiplier;
520 /** Enable tx pacing for new connections */
523 /** Default congestion control algorithm type */
524 tcp_cc_algorithm_type_e cc_algo;
526 /** Delayed ack time (disabled) */
529 /** Timer ticks to wait for close from app */
532 /** Timer ticks to wait in time-wait. Also known as 2MSL */
535 /** Timer ticks to wait in fin-wait1 to send fin and rcv fin-ack */
538 /** Timer ticks to wait in last ack for ack */
541 /** Timer ticks to wait in fin-wait2 for fin */
544 /** Timer ticks to wait in closing for fin ack */
547 /** Timer ticks to wait before cleaning up the connection */
550 /** Number of preallocated connections */
551 u32 preallocated_connections;
553 /** Number of preallocated half-open connections */
554 u32 preallocated_half_open_connections;
556 /** Vectors of src addresses. Optional unless one needs > 63K active-opens */
557 ip4_address_t *ip4_src_addrs;
558 ip6_address_t *ip6_src_addrs;
560 /** Fault-injection. Debug only */
561 f64 buffer_fail_fraction;
562 } tcp_configuration_t;
564 typedef struct _tcp_main
566 /* Per-worker thread tcp connection pools */
567 tcp_connection_t **connections;
569 /* Pool of listeners. */
570 tcp_connection_t *listener_pool;
572 /** Dispatch table by state and flags */
573 tcp_lookup_dispatch_t dispatch_table[TCP_N_STATES][64];
575 u8 log2_tstamp_clocks_per_tick;
576 f64 tstamp_ticks_per_clock;
578 /** per-worker context */
579 tcp_worker_ctx_t *wrk_ctx;
581 /** Pool of half-open connections on which we've sent a SYN */
582 tcp_connection_t *half_open_connections;
583 clib_spinlock_t half_open_lock;
585 /** vlib buffer size */
586 u32 bytes_per_buffer;
588 /** Seed used to generate random iss */
589 tcp_iss_seed_t iss_seed;
591 /** Congestion control algorithms registered */
592 tcp_cc_algorithm_t *cc_algos;
594 /** Hash table of cc algorithms by name */
595 uword *cc_algo_by_name;
597 /** Last cc algo registered */
598 tcp_cc_algorithm_type_e cc_last_type;
600 /** Flag that indicates if stack is on or off */
603 /** Flag that indicates if v4 punting is enabled */
606 /** Flag that indicates if v6 punting is enabled */
609 /** Rotor for v4 source addresses */
610 u32 last_v4_addr_rotor;
612 /** Rotor for v6 source addresses */
613 u32 last_v6_addr_rotor;
615 /** Protocol configuration */
616 tcp_configuration_t cfg;
619 extern tcp_main_t tcp_main;
620 extern vlib_node_registration_t tcp4_input_node;
621 extern vlib_node_registration_t tcp6_input_node;
622 extern vlib_node_registration_t tcp4_output_node;
623 extern vlib_node_registration_t tcp6_output_node;
624 extern vlib_node_registration_t tcp4_established_node;
625 extern vlib_node_registration_t tcp6_established_node;
626 extern vlib_node_registration_t tcp4_syn_sent_node;
627 extern vlib_node_registration_t tcp6_syn_sent_node;
628 extern vlib_node_registration_t tcp4_rcv_process_node;
629 extern vlib_node_registration_t tcp6_rcv_process_node;
630 extern vlib_node_registration_t tcp4_listen_node;
631 extern vlib_node_registration_t tcp6_listen_node;
633 #define tcp_cfg tcp_main.cfg
634 #define tcp_node_index(node_id, is_ip4) \
635 ((is_ip4) ? tcp4_##node_id##_node.index : tcp6_##node_id##_node.index)
637 always_inline tcp_main_t *
643 always_inline tcp_worker_ctx_t *
644 tcp_get_worker (u32 thread_index)
646 return &tcp_main.wrk_ctx[thread_index];
649 always_inline tcp_header_t *
650 tcp_buffer_hdr (vlib_buffer_t * b)
652 ASSERT ((signed) b->current_data >= (signed) -VLIB_BUFFER_PRE_DATA_SIZE);
653 return (tcp_header_t *) (b->data + b->current_data
654 + vnet_buffer (b)->tcp.hdr_offset);
657 #if (VLIB_BUFFER_TRACE_TRAJECTORY)
658 #define tcp_trajectory_add_start(b, start) \
660 (*vlib_buffer_trace_trajectory_cb) (b, start); \
663 #define tcp_trajectory_add_start(b, start)
666 clib_error_t *vnet_tcp_enable_disable (vlib_main_t * vm, u8 is_en);
668 void tcp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add);
670 always_inline tcp_connection_t *
671 tcp_connection_get (u32 conn_index, u32 thread_index)
674 (pool_is_free_index (tcp_main.connections[thread_index], conn_index)))
676 return pool_elt_at_index (tcp_main.connections[thread_index], conn_index);
679 always_inline tcp_connection_t *
680 tcp_connection_get_if_valid (u32 conn_index, u32 thread_index)
682 if (tcp_main.connections[thread_index] == 0)
684 if (pool_is_free_index (tcp_main.connections[thread_index], conn_index))
686 return pool_elt_at_index (tcp_main.connections[thread_index], conn_index);
689 always_inline tcp_connection_t *
690 tcp_get_connection_from_transport (transport_connection_t * tconn)
692 return (tcp_connection_t *) tconn;
696 tcp_connection_set_state (tcp_connection_t * tc, tcp_state_t state)
699 TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc);
702 void tcp_connection_close (tcp_connection_t * tc);
703 void tcp_connection_cleanup (tcp_connection_t * tc);
704 void tcp_connection_del (tcp_connection_t * tc);
705 int tcp_half_open_connection_cleanup (tcp_connection_t * tc);
706 tcp_connection_t *tcp_connection_alloc (u8 thread_index);
707 void tcp_connection_free (tcp_connection_t * tc);
708 void tcp_connection_reset (tcp_connection_t * tc);
709 int tcp_configure_v4_source_address_range (vlib_main_t * vm,
710 ip4_address_t * start,
711 ip4_address_t * end, u32 table_id);
712 int tcp_configure_v6_source_address_range (vlib_main_t * vm,
713 ip6_address_t * start,
714 ip6_address_t * end, u32 table_id);
715 void tcp_api_reference (void);
716 u8 *format_tcp_connection (u8 * s, va_list * args);
718 always_inline tcp_connection_t *
719 tcp_listener_get (u32 tli)
721 return pool_elt_at_index (tcp_main.listener_pool, tli);
724 always_inline tcp_connection_t *
725 tcp_half_open_connection_get (u32 conn_index)
727 tcp_connection_t *tc = 0;
728 clib_spinlock_lock_if_init (&tcp_main.half_open_lock);
729 if (!pool_is_free_index (tcp_main.half_open_connections, conn_index))
730 tc = pool_elt_at_index (tcp_main.half_open_connections, conn_index);
731 clib_spinlock_unlock_if_init (&tcp_main.half_open_lock);
735 void tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b);
736 void tcp_make_synack (tcp_connection_t * ts, vlib_buffer_t * b);
737 void tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
738 u32 thread_index, u8 is_ip4);
739 void tcp_send_reset (tcp_connection_t * tc);
740 void tcp_send_syn (tcp_connection_t * tc);
741 void tcp_send_synack (tcp_connection_t * tc);
742 void tcp_send_fin (tcp_connection_t * tc);
743 void tcp_init_mss (tcp_connection_t * tc);
744 void tcp_update_burst_snd_vars (tcp_connection_t * tc);
745 void tcp_update_rto (tcp_connection_t * tc);
746 void tcp_flush_frame_to_output (tcp_worker_ctx_t * wrk, u8 is_ip4);
747 void tcp_flush_frames_to_output (tcp_worker_ctx_t * wrk);
748 void tcp_send_window_update_ack (tcp_connection_t * tc);
750 void tcp_program_ack (tcp_connection_t * tc);
751 void tcp_program_dupack (tcp_connection_t * tc);
752 void tcp_program_fastretransmit (tcp_connection_t * tc);
759 * Byte tracker initialize
761 * @param tc connection for which the byte tracker should be allocated and
764 void tcp_bt_init (tcp_connection_t * tc);
766 * Byte tracker cleanup
768 * @param tc connection for which the byte tracker should be cleaned up
770 void tcp_bt_cleanup (tcp_connection_t * tc);
772 * Flush byte tracker samples
774 * @param tc tcp connection for which samples should be flushed
776 void tcp_bt_flush_samples (tcp_connection_t * tc);
778 * Track a tcp tx burst
780 * @param tc tcp connection
782 void tcp_bt_track_tx (tcp_connection_t * tc);
784 * Track a tcp retransmission
786 * @param tc tcp connection
787 * @param start start sequence number
788 * @param end end sequence number
790 void tcp_bt_track_rxt (tcp_connection_t * tc, u32 start, u32 end);
792 * Generate a delivery rate sample from recently acked bytes
794 * @param tc tcp connection
795 * @param rs resulting rate sample
797 void tcp_bt_sample_delivery_rate (tcp_connection_t * tc,
798 tcp_rate_sample_t * rs);
800 * Check if sample to be generated is app limited
802 * @param tc tcp connection
804 void tcp_bt_check_app_limited (tcp_connection_t * tc);
806 * Check if the byte tracker is in sane state
808 * Should be used only for testing
810 * @param bt byte tracker
812 int tcp_bt_is_sane (tcp_byte_tracker_t * bt);
815 tcp_end_seq (tcp_header_t * th, u32 len)
817 return th->seq_number + tcp_is_syn (th) + tcp_is_fin (th) + len;
820 /* Modulo arithmetic for TCP sequence numbers */
821 #define seq_lt(_s1, _s2) ((i32)((_s1)-(_s2)) < 0)
822 #define seq_leq(_s1, _s2) ((i32)((_s1)-(_s2)) <= 0)
823 #define seq_gt(_s1, _s2) ((i32)((_s1)-(_s2)) > 0)
824 #define seq_geq(_s1, _s2) ((i32)((_s1)-(_s2)) >= 0)
825 #define seq_max(_s1, _s2) (seq_gt((_s1), (_s2)) ? (_s1) : (_s2))
827 /* Modulo arithmetic for timestamps */
828 #define timestamp_lt(_t1, _t2) ((i32)((_t1)-(_t2)) < 0)
829 #define timestamp_leq(_t1, _t2) ((i32)((_t1)-(_t2)) <= 0)
832 * Our estimate of the number of bytes that have left the network
835 tcp_bytes_out (const tcp_connection_t * tc)
837 if (tcp_opts_sack_permitted (&tc->rcv_opts))
838 return tc->sack_sb.sacked_bytes + tc->sack_sb.lost_bytes;
840 return tc->rcv_dupacks * tc->snd_mss;
844 * Our estimate of the number of bytes in flight (pipe size)
847 tcp_flight_size (const tcp_connection_t * tc)
851 flight_size = (int) (tc->snd_nxt - tc->snd_una) - tcp_bytes_out (tc)
858 ("Negative: %u %u %u dupacks %u sacked bytes %u flags %d",
859 tc->snd_una_max - tc->snd_una, tcp_bytes_out (tc),
860 tc->snd_rxt_bytes, tc->rcv_dupacks, tc->sack_sb.sacked_bytes,
869 * Initial cwnd as per RFC5681
872 tcp_initial_cwnd (const tcp_connection_t * tc)
874 if (tcp_cfg.initial_cwnd_multiplier > 0)
875 return tcp_cfg.initial_cwnd_multiplier * tc->snd_mss;
877 if (tc->snd_mss > 2190)
878 return 2 * tc->snd_mss;
879 else if (tc->snd_mss > 1095)
880 return 3 * tc->snd_mss;
882 return 4 * tc->snd_mss;
886 * Accumulate acked bytes for cwnd increase
888 * Once threshold bytes are accumulated, snd_mss bytes are added
892 tcp_cwnd_accumulate (tcp_connection_t * tc, u32 thresh, u32 bytes)
894 tc->cwnd_acc_bytes += bytes;
895 if (tc->cwnd_acc_bytes >= thresh)
897 u32 inc = tc->cwnd_acc_bytes / thresh;
898 tc->cwnd_acc_bytes -= inc * thresh;
899 tc->cwnd += inc * tc->snd_mss;
900 tc->cwnd = clib_min (tc->cwnd, tc->tx_fifo_size);
905 tcp_loss_wnd (const tcp_connection_t * tc)
911 tcp_available_snd_wnd (const tcp_connection_t * tc)
913 return clib_min (tc->cwnd, tc->snd_wnd);
917 tcp_available_output_snd_space (const tcp_connection_t * tc)
919 u32 available_wnd = tcp_available_snd_wnd (tc);
920 int flight_size = (int) (tc->snd_nxt - tc->snd_una);
922 if (available_wnd <= flight_size)
925 return available_wnd - flight_size;
929 * Estimate of how many bytes we can still push into the network
932 tcp_available_cc_snd_space (const tcp_connection_t * tc)
934 u32 available_wnd = tcp_available_snd_wnd (tc);
935 u32 flight_size = tcp_flight_size (tc);
937 if (available_wnd <= flight_size)
940 return available_wnd - flight_size;
944 tcp_is_lost_fin (tcp_connection_t * tc)
946 if ((tc->flags & TCP_CONN_FINSNT) && tc->snd_una_max - tc->snd_una == 1)
951 u32 tcp_snd_space (tcp_connection_t * tc);
952 int tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk,
953 tcp_connection_t * tc);
954 int tcp_fast_retransmit_no_sack (tcp_worker_ctx_t * wrk,
955 tcp_connection_t * tc, u32 burst_size);
956 int tcp_fast_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
958 int tcp_fast_retransmit (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
960 void tcp_cc_init_congestion (tcp_connection_t * tc);
961 void tcp_cc_fastrecovery_clear (tcp_connection_t * tc);
963 fib_node_index_t tcp_lookup_rmt_in_fib (tcp_connection_t * tc);
965 /* Made public for unit testing only */
966 void tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end);
967 u32 tcp_sack_list_bytes (tcp_connection_t * tc);
972 return tcp_main.wrk_ctx[vlib_get_thread_index ()].time_now;
976 tcp_time_now_w_thread (u32 thread_index)
978 return tcp_main.wrk_ctx[thread_index].time_now;
982 * Generate timestamp for tcp connection
985 tcp_tstamp (tcp_connection_t * tc)
987 return (tcp_main.wrk_ctx[tc->c_thread_index].time_now -
988 tc->timestamp_delta);
992 tcp_time_now_us (u32 thread_index)
994 return transport_time_now (thread_index);
998 tcp_set_time_now (tcp_worker_ctx_t * wrk)
1000 wrk->time_now = clib_cpu_time_now () * tcp_main.tstamp_ticks_per_clock;
1001 return wrk->time_now;
1004 u32 tcp_session_push_header (transport_connection_t * tconn,
1006 int tcp_session_custom_tx (void *conn, u32 max_burst_size);
1008 void tcp_connection_timers_init (tcp_connection_t * tc);
1009 void tcp_connection_timers_reset (tcp_connection_t * tc);
1010 void tcp_init_snd_vars (tcp_connection_t * tc);
1011 void tcp_connection_init_vars (tcp_connection_t * tc);
1012 void tcp_connection_tx_pacer_update (tcp_connection_t * tc);
1013 void tcp_connection_tx_pacer_reset (tcp_connection_t * tc, u32 window,
1017 tcp_cc_rcv_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
1019 tc->cc_algo->rcv_ack (tc, rs);
1020 tc->tsecr_last_ack = tc->rcv_opts.tsecr;
1024 tcp_cc_rcv_cong_ack (tcp_connection_t * tc, tcp_cc_ack_t ack_type,
1025 tcp_rate_sample_t * rs)
1027 tc->cc_algo->rcv_cong_ack (tc, ack_type, rs);
1031 tcp_cc_loss (tcp_connection_t * tc)
1033 tc->cc_algo->loss (tc);
1037 tcp_cc_recovered (tcp_connection_t * tc)
1039 tc->cc_algo->recovered (tc);
1043 tcp_cc_undo_recovery (tcp_connection_t * tc)
1045 if (tc->cc_algo->undo_recovery)
1046 tc->cc_algo->undo_recovery (tc);
1050 tcp_cc_event (tcp_connection_t * tc, tcp_cc_event_t evt)
1052 if (tc->cc_algo->event)
1053 tc->cc_algo->event (tc, evt);
1057 tcp_timer_set (tcp_connection_t * tc, u8 timer_id, u32 interval)
1059 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
1060 ASSERT (tc->timers[timer_id] == TCP_TIMER_HANDLE_INVALID);
1061 tc->timers[timer_id] =
1062 tw_timer_start_16t_2w_512sl (&tcp_main.
1063 wrk_ctx[tc->c_thread_index].timer_wheel,
1064 tc->c_c_index, timer_id, interval);
1068 tcp_timer_reset (tcp_connection_t * tc, u8 timer_id)
1070 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
1071 if (tc->timers[timer_id] == TCP_TIMER_HANDLE_INVALID)
1074 tw_timer_stop_16t_2w_512sl (&tcp_main.
1075 wrk_ctx[tc->c_thread_index].timer_wheel,
1076 tc->timers[timer_id]);
1077 tc->timers[timer_id] = TCP_TIMER_HANDLE_INVALID;
1081 tcp_timer_update (tcp_connection_t * tc, u8 timer_id, u32 interval)
1083 ASSERT (tc->c_thread_index == vlib_get_thread_index ());
1084 if (tc->timers[timer_id] != TCP_TIMER_HANDLE_INVALID)
1085 tw_timer_update_16t_2w_512sl (&tcp_main.
1086 wrk_ctx[tc->c_thread_index].timer_wheel,
1087 tc->timers[timer_id], interval);
1089 tc->timers[timer_id] =
1090 tw_timer_start_16t_2w_512sl (&tcp_main.
1091 wrk_ctx[tc->c_thread_index].timer_wheel,
1092 tc->c_c_index, timer_id, interval);
1096 tcp_retransmit_timer_set (tcp_connection_t * tc)
1098 ASSERT (tc->snd_una != tc->snd_una_max);
1099 tcp_timer_set (tc, TCP_TIMER_RETRANSMIT,
1100 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1104 tcp_retransmit_timer_reset (tcp_connection_t * tc)
1106 tcp_timer_reset (tc, TCP_TIMER_RETRANSMIT);
1110 tcp_retransmit_timer_force_update (tcp_connection_t * tc)
1112 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
1113 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1117 tcp_persist_timer_set (tcp_connection_t * tc)
1119 /* Reuse RTO. It's backed off in handler */
1120 tcp_timer_set (tc, TCP_TIMER_PERSIST,
1121 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1125 tcp_persist_timer_update (tcp_connection_t * tc)
1127 tcp_timer_update (tc, TCP_TIMER_PERSIST,
1128 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1132 tcp_persist_timer_reset (tcp_connection_t * tc)
1134 tcp_timer_reset (tc, TCP_TIMER_PERSIST);
1138 tcp_retransmit_timer_update (tcp_connection_t * tc)
1140 if (tc->snd_una == tc->snd_nxt)
1142 tcp_retransmit_timer_reset (tc);
1143 if (tc->snd_wnd < tc->snd_mss)
1144 tcp_persist_timer_update (tc);
1147 tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
1148 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
1152 tcp_timer_is_active (tcp_connection_t * tc, tcp_timers_e timer)
1154 return tc->timers[timer] != TCP_TIMER_HANDLE_INVALID;
1157 #define tcp_validate_txf_size(_tc, _a) \
1158 ASSERT(_tc->state != TCP_STATE_ESTABLISHED \
1159 || transport_max_tx_dequeue (&_tc->connection) >= _a)
1161 void tcp_rcv_sacks (tcp_connection_t * tc, u32 ack);
1162 u8 *tcp_scoreboard_replay (u8 * s, tcp_connection_t * tc, u8 verbose);
1165 * Register exiting cc algo type
1167 void tcp_cc_algo_register (tcp_cc_algorithm_type_e type,
1168 const tcp_cc_algorithm_t * vft);
1171 * Register new cc algo type
1173 tcp_cc_algorithm_type_e tcp_cc_algo_new_type (const tcp_cc_algorithm_t * vft);
1174 tcp_cc_algorithm_t *tcp_cc_algo_get (tcp_cc_algorithm_type_e type);
1176 static inline void *
1177 tcp_cc_data (tcp_connection_t * tc)
1179 return (void *) tc->cc_data;
1182 void newreno_rcv_cong_ack (tcp_connection_t * tc, tcp_cc_ack_t ack_type,
1183 tcp_rate_sample_t * rs);
1186 * Push TCP header to buffer
1188 * @param vm - vlib_main
1189 * @param b - buffer to write the header to
1190 * @param sp_net - source port net order
1191 * @param dp_net - destination port net order
1192 * @param seq - sequence number net order
1193 * @param ack - ack number net order
1194 * @param tcp_hdr_opts_len - header and options length in bytes
1195 * @param flags - header flags
1196 * @param wnd - window size
1198 * @return - pointer to start of TCP header
1200 always_inline void *
1201 vlib_buffer_push_tcp_net_order (vlib_buffer_t * b, u16 sp, u16 dp, u32 seq,
1202 u32 ack, u8 tcp_hdr_opts_len, u8 flags,
1207 th = vlib_buffer_push_uninit (b, tcp_hdr_opts_len);
1211 th->seq_number = seq;
1212 th->ack_number = ack;
1213 th->data_offset_and_reserved = (tcp_hdr_opts_len >> 2) << 4;
1217 th->urgent_pointer = 0;
1222 * Push TCP header to buffer
1224 * @param b - buffer to write the header to
1225 * @param sp_net - source port net order
1226 * @param dp_net - destination port net order
1227 * @param seq - sequence number host order
1228 * @param ack - ack number host order
1229 * @param tcp_hdr_opts_len - header and options length in bytes
1230 * @param flags - header flags
1231 * @param wnd - window size
1233 * @return - pointer to start of TCP header
1235 always_inline void *
1236 vlib_buffer_push_tcp (vlib_buffer_t * b, u16 sp_net, u16 dp_net, u32 seq,
1237 u32 ack, u8 tcp_hdr_opts_len, u8 flags, u16 wnd)
1239 return vlib_buffer_push_tcp_net_order (b, sp_net, dp_net,
1240 clib_host_to_net_u32 (seq),
1241 clib_host_to_net_u32 (ack),
1242 tcp_hdr_opts_len, flags,
1243 clib_host_to_net_u16 (wnd));
1246 #endif /* _vnet_tcp_h_ */
1249 * fd.io coding-style-patch-verification: ON
1252 * eval: (c-set-style "gnu")