2 * Copyright (c) 2017 SUSE LLC.
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.
15 #ifndef included_vnet_sctp_h
16 #define included_vnet_sctp_h
18 #include <vnet/vnet.h>
19 #include <vnet/ip/ip.h>
20 #include <vnet/sctp/sctp_timer.h>
21 #include <vnet/sctp/sctp_packet.h>
22 #include <vnet/session/transport.h>
23 #include <vnet/session/session.h>
26 #define foreach_sctp_timer \
27 _(T1_INIT, "T1_INIT") \
28 _(T1_COOKIE, "T1_COOKIE") \
29 _(T2_SHUTDOWN, "T2_SHUTDOWN") \
30 _(T3_RXTX, "T3_RXTX") \
31 _(T4_HEARTBEAT, "T4_HB") \
32 _(T5_SHUTDOWN_GUARD, "T5_SHUTDOWN_GUARD")
34 typedef enum _sctp_timers
36 #define _(sym, str) SCTP_TIMER_##sym,
42 #define SCTP_TIMER_HANDLE_INVALID ((u32) ~0)
45 sctp_timer_to_string (u8 timer_id)
49 case SCTP_TIMER_T1_INIT:
50 return "SCTP_TIMER_T1_INIT";
51 case SCTP_TIMER_T1_COOKIE:
52 return "SCTP_TIMER_T1_COOKIE";
53 case SCTP_TIMER_T2_SHUTDOWN:
54 return "SCTP_TIMER_T2_SHUTDOWN";
55 case SCTP_TIMER_T3_RXTX:
56 return "SCTP_TIMER_T3_RXTX";
57 case SCTP_TIMER_T4_HEARTBEAT:
58 return "SCTP_TIMER_T4_HEARTBEAT";
59 case SCTP_TIMER_T5_SHUTDOWN_GUARD:
60 return "SCTP_TIMER_T5_SHUTDOWN_GUARD";
65 typedef enum _sctp_error
67 #define sctp_error(n,s) SCTP_ERROR_##n,
68 #include <vnet/sctp/sctp_error.def>
75 #define IS_T_BIT_SET(var) ((var) & (1))
76 #define IS_E_BIT_SET(var) ((var) & (1))
77 #define IS_B_BIT_SET(var) ((var) & (1<<1))
78 #define IS_U_BIT_SET(var) ((var) & (1<<2))
80 #define MAX_SCTP_CONNECTIONS 8
81 #define MAIN_SCTP_SUB_CONN_IDX 0
83 #if (VLIB_BUFFER_TRACE_TRAJECTORY)
84 #define sctp_trajectory_add_start(b, start) \
86 (*vlib_buffer_trace_trajectory_cb) (b, start); \
89 #define sctp_trajectory_add_start(b, start)
92 enum _sctp_subconn_state
94 SCTP_SUBCONN_STATE_DOWN = 0,
95 SCTP_SUBCONN_STATE_UP,
96 SCTP_SUBCONN_STATE_ALLOW_HB
99 #define SCTP_INITIAL_SSHTRESH 65535
100 typedef struct _sctp_sub_connection
102 transport_connection_t connection; /**< Common transport data. First! */
104 u8 subconn_idx; /**< This indicates the position of this sub-connection in the super-set container of connections pool */
105 u32 error_count; /**< The current error count for this destination. */
106 u32 error_threshold; /**< Current error threshold for this destination,
107 i.e. what value marks the destination down if error count reaches this value. */
108 u32 cwnd; /**< Congestion control window (cwnd, in bytes), which is adjusted by
109 the sender based on observed network conditions. */
110 u32 ssthresh; /**< Slow-start threshold (in bytes), which is used by the
111 sender to distinguish slow-start and congestion avoidance phases. */
113 u32 rtt_ts; /**< USED to hold the timestamp of when the packet has been sent */
115 u32 RTO; /**< The current retransmission timeout value. */
116 u32 SRTT; /**< The current smoothed round-trip time. */
117 f32 RTTVAR; /**< The current RTT variation. */
119 u32 partially_acked_bytes; /**< The tracking method for increase of cwnd when in
120 congestion avoidance mode (see Section 7.2.2).*/
122 u8 state; /**< The current state of this destination, i.e., DOWN, UP, ALLOW-HB, NO-HEARTBEAT, etc. */
124 u16 PMTU; /**< The current known path MTU. */
126 u32 timers[SCTP_N_TIMERS]; /**< A timer used by each destination. */
128 u8 RTO_pending; /**< A flag used to track if one of the DATA chunks sent to
129 this address is currently being used to compute an RTT.
130 If this flag is 0, the next DATA chunk sent to this destination
131 should be used to compute an RTT and this flag should be set.
132 Every time the RTT calculation completes (i.e., the DATA chunk is SACK'd),
135 u32 last_seen; /**< The time to which this destination was last sent a packet to.
136 This can be used to determine if a HEARTBEAT is needed. */
138 u32 last_data_ts; /**< Used to hold the timestamp value of last time we sent a DATA chunk */
140 u8 unacknowledged_hb; /**< Used to track how many unacknowledged heartbeats we had;
141 If more than SCTP_PATH_MAX_RETRANS then connection is considered unreachable. */
143 u8 is_retransmitting; /**< A flag (0 = no, 1 = yes) indicating whether the connection is retransmitting a previous packet */
145 u8 enqueue_state; /**< if set to 1 indicates that DATA is still being handled hence cannot shutdown this connection yet */
147 } sctp_sub_connection_t;
151 u32 a_rwnd; /**< Maximum segment size advertised */
155 /* Useful macros to deal with the out_of_order_map (array of bit) */
156 #define SET_BIT(A,k) ( A[(k/32)] |= (1 << (k%32)) )
157 #define CLEAR_BIT(A,k) ( A[(k/32)] &= ~(1 << (k%32)) )
158 #define TEST_BIT(A,k) ( A[(k/32)] & (1 << (k%32)) )
161 _bytes_swap (void *pv, size_t n)
165 for (lo = 0, hi = n - 1; hi > lo; lo++, hi--)
173 #define ENDIANESS_SWAP(x) _bytes_swap(&x, sizeof(x));
175 #define MAX_INFLIGHT_PACKETS 128
176 #define MAX_ENQUEABLE_SACKS 2
178 /* This parameter indicates to the receiver how much increment in
179 * milliseconds the sender wishes the receiver to add to its default
182 #define SUGGESTED_COOKIE_LIFE_SPAN_INCREMENT 1000
184 typedef struct _sctp_connection
186 sctp_sub_connection_t sub_conn[MAX_SCTP_CONNECTIONS]; /**< Common transport data. First! */
188 u8 state; /**< SCTP state as per sctp_state_t */
189 u16 flags; /**< Chunk flag (see sctp_chunks_common_hdr_t) */
191 u32 local_tag; /**< INIT_TAG generated locally */
192 u32 remote_tag; /**< INIT_TAG generated by the remote peer */
194 u32 local_initial_tsn; /**< Initial TSN generated locally */
195 u32 remote_initial_tsn; /**< Initial TSN generated by the remote-peer */
197 u32 peer_cookie_life_span_increment;
199 u32 overall_err_count; /**< The overall association error count. */
200 u32 overall_err_treshold; /**< The threshold for this association that if the Overall Error Count
201 reaches will cause this association to be torn down. */
203 u32 peer_rwnd; /**< Current calculated value of the peer's rwnd. */
205 u32 next_tsn; /**< The next TSN number to be assigned to a new DATA chunk.
206 This is sent in the INIT or INIT ACK chunk to the peer
207 and incremented each time a DATA chunk is assigned a
208 TSN (normally just prior to transmit or during
211 u32 last_unacked_tsn; /** < Last TSN number still unacked */
212 u32 next_tsn_expected; /**< The next TSN number expected to be received. */
214 u32 last_rcvd_tsn; /**< This is the last TSN received in sequence. This value
215 is set initially by taking the peer's initial TSN,
216 received in the INIT or INIT ACK chunk, and
217 subtracting one from it. */
219 u32 out_of_order_map[MAX_INFLIGHT_PACKETS]; /**< An array of bits or bytes indicating which out-of-order
220 TSNs have been received (relative to the Last Rcvd TSN).
221 If no gaps exist, i.e., no out-of-order packets have been received,
222 this array will be set to all zero. */
224 u8 ack_state; /**< This flag indicates if the next received packet is set to be responded to with a SACK.
225 This is initialized to 0. When a packet is received it is incremented.
226 If this value reaches 2 or more, a SACK is sent and the value is reset to 0.
227 Note: This is used only when no DATA chunks are received out-of-order.
228 When DATA chunks are out-of-order, SACKs are not delayed (see Section 6). */
230 u8 smallest_PMTU_idx; /** The index of the sub-connection with the smallest PMTU discovered across all peer's transport addresses. */
232 u8 overall_sending_status; /**< 0 indicates first fragment of a user message
233 1 indicates normal stream
234 2 indicates last fragment of a user message */
236 sctp_options_t snd_opts;
238 u8 next_avail_sub_conn; /**< Represent the index of the next free slot in sub_conn */
240 u8 forming_association_changed; /**< This is a flag indicating whether the original association has been modified during
241 the life-span of the association itself. For instance, a new sub-connection might have been added. */
245 typedef void (sctp_timer_expiration_handler) (u32 conn_index, u32 timer_id);
247 sctp_connection_t *sctp_connection_new (u8 thread_index);
248 void sctp_sub_connection_add_ip4 (u8 thread_index,
249 sctp_ipv4_addr_param_t * ipv4_addr);
250 void sctp_sub_connection_add_ip6 (u8 thread_index,
251 sctp_ipv6_addr_param_t * ipv6_addr);
252 void sctp_connection_close (sctp_connection_t * sctp_conn);
253 void sctp_connection_cleanup (sctp_connection_t * sctp_conn);
254 void sctp_connection_del (sctp_connection_t * sctp_conn);
256 u32 sctp_push_header (transport_connection_t * tconn, vlib_buffer_t * b);
257 void sctp_send_init (sctp_connection_t * sctp_conn);
258 void sctp_send_shutdown (sctp_connection_t * sctp_conn);
259 void sctp_send_shutdown_ack (sctp_connection_t * sctp_conn, u8 idx,
261 void sctp_send_shutdown_complete (sctp_connection_t * sctp_conn, u8 idx,
263 void sctp_send_heartbeat (sctp_connection_t * sctp_conn);
264 void sctp_flush_frame_to_output (vlib_main_t * vm, u8 thread_index,
266 void sctp_flush_frames_to_output (u8 thread_index);
267 void sctp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add);
269 format_function_t format_sctp_state;
271 u8 *format_sctp_connection_id (u8 * s, va_list * args);
272 u8 *format_sctp_connection (u8 * s, va_list * args);
273 u8 *format_sctp_scoreboard (u8 * s, va_list * args);
274 u8 *format_sctp_header (u8 * s, va_list * args);
275 u8 *format_sctp_tx_trace (u8 * s, va_list * args);
277 clib_error_t *sctp_init (vlib_main_t * vm);
278 void sctp_connection_timers_init (sctp_connection_t * sctp_conn);
279 void sctp_connection_timers_reset (sctp_connection_t * sctp_conn);
280 void sctp_init_snd_vars (sctp_connection_t * sctp_conn);
281 void sctp_init_mss (sctp_connection_t * sctp_conn);
283 void sctp_prepare_initack_chunk (sctp_connection_t * sctp_conn, u8 idx,
284 vlib_buffer_t * b, ip4_address_t * ip4_addr,
285 ip6_address_t * ip6_addr);
287 sctp_prepare_initack_chunk_for_collision (sctp_connection_t * sctp_conn,
288 u8 idx, vlib_buffer_t * b,
289 ip4_address_t * ip4_addr,
290 ip6_address_t * ip6_addr);
291 void sctp_prepare_abort_for_collision (sctp_connection_t * sctp_conn, u8 idx,
293 ip4_address_t * ip4_addr,
294 ip6_address_t * ip6_addr);
296 void sctp_prepare_cookie_echo_chunk (sctp_connection_t * sctp_conn, u8 idx,
298 sctp_state_cookie_param_t * sc);
299 void sctp_prepare_cookie_ack_chunk (sctp_connection_t * sctp_conn, u8 idx,
301 void sctp_prepare_sack_chunk (sctp_connection_t * sctp_conn, u8 idx,
303 void sctp_prepare_heartbeat_ack_chunk (sctp_connection_t * sctp_conn, u8 idx,
306 u16 sctp_check_outstanding_data_chunks (sctp_connection_t * sctp_conn);
308 #define IP_PROTOCOL_SCTP 132
310 /** SSCTP FSM state definitions as per RFC4960. */
311 #define foreach_sctp_fsm_state \
312 _(CLOSED, "CLOSED") \
313 _(COOKIE_WAIT, "COOKIE_WAIT") \
314 _(COOKIE_ECHOED, "COOKIE_ECHOED") \
315 _(ESTABLISHED, "ESTABLISHED") \
316 _(SHUTDOWN_PENDING, "SHUTDOWN_PENDING") \
317 _(SHUTDOWN_SENT, "SHUTDOWN_SENT") \
318 _(SHUTDOWN_RECEIVED, "SHUTDOWN_RECEIVED") \
319 _(SHUTDOWN_ACK_SENT, "SHUTDOWN_ACK_SENT")
321 typedef enum _sctp_state
323 #define _(sym, str) SCTP_STATE_##sym,
324 foreach_sctp_fsm_state
330 sctp_state_to_string (u8 state)
334 case SCTP_STATE_CLOSED:
335 return "SCTP_STATE_CLOSED";
336 case SCTP_STATE_COOKIE_WAIT:
337 return "SCTP_STATE_COOKIE_WAIT";
338 case SCTP_STATE_COOKIE_ECHOED:
339 return "SCTP_STATE_COOKIE_ECHOED";
340 case SCTP_STATE_ESTABLISHED:
341 return "SCTP_STATE_ESTABLISHED";
342 case SCTP_STATE_SHUTDOWN_PENDING:
343 return "SCTP_STATE_SHUTDOWN_PENDING";
344 case SCTP_STATE_SHUTDOWN_SENT:
345 return "SCTP_STATE_SHUTDOWN_SENT";
346 case SCTP_STATE_SHUTDOWN_RECEIVED:
347 return "SCTP_STATE_SHUTDOWN_RECEIVED";
348 case SCTP_STATE_SHUTDOWN_ACK_SENT:
349 return "SCTP_STATE_SHUTDOWN_ACK_SENT";
355 sctp_chunk_to_string (u8 type)
370 return "HEARTBEAT_ACK";
376 return "SHUTDOWN_ACK";
377 case OPERATION_ERROR:
378 return "OPERATION_ERROR";
380 return "COOKIE_ECHO";
387 case SHUTDOWN_COMPLETE:
388 return "SHUTDOWN_COMPLETE";
394 sctp_optparam_type_to_string (u8 type)
398 case SCTP_IPV4_ADDRESS_TYPE:
399 return "SCTP_IPV4_ADDRESS_TYPE";
400 case SCTP_IPV6_ADDRESS_TYPE:
401 return "SCTP_IPV6_ADDRESS_TYPE";
402 case SCTP_STATE_COOKIE_TYPE:
403 return "SCTP_STATE_COOKIE_TYPE";
404 case SCTP_UNRECOGNIZED_TYPE:
405 return "SCTP_UNRECOGNIZED_TYPE";
406 case SCTP_COOKIE_PRESERVATIVE_TYPE:
407 return "SCTP_COOKIE_PRESERVATIVE_TYPE";
408 case SCTP_HOSTNAME_ADDRESS_TYPE:
409 return "SCTP_HOSTNAME_ADDRESS_TYPE";
410 case SCTP_SUPPORTED_ADDRESS_TYPES:
411 return "SCTP_SUPPORTED_ADDRESS_TYPES";
416 #define SCTP_TICK 0.001 /**< SCTP tick period (s) */
417 #define SHZ (u32) (1/SCTP_TICK) /**< SCTP tick frequency */
418 #define SCTP_TSTAMP_RESOLUTION SCTP_TICK /**< Time stamp resolution */
420 /* As per RFC4960, page 83 */
421 #define SCTP_RTO_INIT 3 * SHZ /* 3 seconds */
422 #define SCTP_RTO_MIN 1 * SHZ /* 1 second */
423 #define SCTP_RTO_MAX 60 * SHZ /* 60 seconds */
424 #define SCTP_RTO_BURST 4
425 #define SCTP_RTO_ALPHA 1/8
426 #define SCTP_RTO_BETA 1/4
427 #define SCTP_VALID_COOKIE_LIFE 60 * SHZ /* 60 seconds */
428 #define SCTP_ASSOCIATION_MAX_RETRANS 10 // the overall connection
429 #define SCTP_PATH_MAX_RETRANS 5 // number of attempts per destination address
430 #define SCTP_MAX_INIT_RETRANS 8 // number of attempts
431 #define SCTP_HB_INTERVAL 30 * SHZ
432 #define SCTP_HB_MAX_BURST 1
434 #define SCTP_DATA_IDLE_INTERVAL 15 * SHZ /* 15 seconds; the time-interval after which the connetion is considered IDLE */
436 #define SCTP_TO_TIMER_TICK SCTP_TICK*10 /* Period for converting from SCTP_TICK */
438 typedef struct _sctp_lookup_dispatch
441 } sctp_lookup_dispatch_t;
443 typedef struct _sctp_main
445 /* Per-worker thread SCTP connection pools */
446 sctp_connection_t **connections;
448 /* Pool of listeners. */
449 sctp_connection_t *listener_pool;
451 /** Dispatch table by state and flags */
452 sctp_lookup_dispatch_t dispatch_table[SCTP_N_STATES][64];
454 u8 log2_tstamp_clocks_per_tick;
455 f64 tstamp_ticks_per_clock;
458 /** per-worker tx buffer free lists */
460 /** per-worker tx frames to SCTP 4/6 output nodes */
461 vlib_frame_t **tx_frames[2];
462 /** per-worker tx frames to ip 4/6 lookup nodes */
463 vlib_frame_t **ip_lookup_tx_frames[2];
465 /* Per worker-thread timer wheel for connections timers */
466 tw_timer_wheel_16t_2w_512sl_t *timer_wheels;
468 /* Pool of half-open connections on which we've sent a SYN */
469 sctp_connection_t *half_open_connections;
470 clib_spinlock_t half_open_lock;
472 /* TODO: Congestion control algorithms registered */
473 /* sctp_cc_algorithm_t *cc_algos; */
475 /* Flag that indicates if stack is on or off */
478 /** Number of preallocated connections */
479 u32 preallocated_connections;
481 /** Transport table (preallocation) size parameters */
482 u32 local_endpoints_table_memory;
483 u32 local_endpoints_table_buckets;
485 /** Vectors of src addresses. Optional unless one needs > 63K active-opens */
486 ip4_address_t *ip4_src_addresses;
487 u32 last_v4_address_rotor;
488 u32 last_v6_address_rotor;
489 ip6_address_t *ip6_src_addresses;
491 /** vlib buffer size */
492 u32 bytes_per_buffer;
499 extern sctp_main_t sctp_main;
500 extern vlib_node_registration_t sctp4_input_node;
501 extern vlib_node_registration_t sctp6_input_node;
502 extern vlib_node_registration_t sctp4_output_node;
503 extern vlib_node_registration_t sctp6_output_node;
505 always_inline sctp_main_t *
506 vnet_get_sctp_main ()
511 always_inline sctp_header_t *
512 sctp_buffer_hdr (vlib_buffer_t * b)
514 ASSERT ((signed) b->current_data >= (signed) -VLIB_BUFFER_PRE_DATA_SIZE);
515 return (sctp_header_t *) (b->data + b->current_data
516 + vnet_buffer (b)->sctp.hdr_offset);
519 clib_error_t *vnet_sctp_enable_disable (vlib_main_t * vm, u8 is_en);
521 always_inline sctp_connection_t *
522 sctp_half_open_connection_get (u32 conn_index)
524 sctp_connection_t *tc = 0;
525 clib_spinlock_lock_if_init (&sctp_main.half_open_lock);
526 if (!pool_is_free_index (sctp_main.half_open_connections, conn_index))
527 tc = pool_elt_at_index (sctp_main.half_open_connections, conn_index);
528 tc->sub_conn[MAIN_SCTP_SUB_CONN_IDX].subconn_idx = MAIN_SCTP_SUB_CONN_IDX;
529 clib_spinlock_unlock_if_init (&sctp_main.half_open_lock);
534 * Cleanup half-open connection
538 sctp_half_open_connection_del (sctp_connection_t * tc)
540 sctp_main_t *sctp_main = vnet_get_sctp_main ();
541 clib_spinlock_lock_if_init (&sctp_main->half_open_lock);
542 pool_put_index (sctp_main->half_open_connections,
543 tc->sub_conn[MAIN_SCTP_SUB_CONN_IDX].c_c_index);
545 memset (tc, 0xFA, sizeof (*tc));
546 clib_spinlock_unlock_if_init (&sctp_main->half_open_lock);
550 sctp_set_time_now (u32 thread_index)
552 sctp_main.time_now[thread_index] = clib_cpu_time_now ()
553 * sctp_main.tstamp_ticks_per_clock;
554 return sctp_main.time_now[thread_index];
558 sctp_timer_set (sctp_connection_t * tc, u8 conn_idx, u8 timer_id,
561 ASSERT (tc->sub_conn[conn_idx].connection.thread_index ==
562 vlib_get_thread_index ());
563 ASSERT (tc->sub_conn[conn_idx].timers[timer_id] ==
564 SCTP_TIMER_HANDLE_INVALID);
566 sctp_sub_connection_t *sub = &tc->sub_conn[conn_idx];
567 sub->timers[timer_id] =
568 tw_timer_start_16t_2w_512sl (&sctp_main.timer_wheels[sub->c_thread_index],
569 sub->c_c_index, timer_id, interval);
573 sctp_timer_reset (sctp_connection_t * tc, u8 conn_idx, u8 timer_id)
575 ASSERT (tc->sub_conn[conn_idx].c_thread_index == vlib_get_thread_index ());
576 if (tc->sub_conn[conn_idx].timers[timer_id] == SCTP_TIMER_HANDLE_INVALID)
579 sctp_sub_connection_t *sub = &tc->sub_conn[conn_idx];
581 tw_timer_stop_16t_2w_512sl (&sctp_main.timer_wheels[sub->c_thread_index],
582 sub->timers[timer_id]);
583 sub->timers[timer_id] = SCTP_TIMER_HANDLE_INVALID;
587 * Try to cleanup half-open connection
589 * If called from a thread that doesn't own tc, the call won't have any
592 * @param tc - connection to be cleaned up
593 * @return non-zero if cleanup failed.
596 sctp_half_open_connection_cleanup (sctp_connection_t * tc)
598 /* Make sure this is the owning thread */
599 if (tc->sub_conn[MAIN_SCTP_SUB_CONN_IDX].c_thread_index !=
600 vlib_get_thread_index ())
602 sctp_timer_reset (tc, MAIN_SCTP_SUB_CONN_IDX, SCTP_TIMER_T1_INIT);
603 sctp_half_open_connection_del (tc);
610 return sizeof (sctp_header_t);
613 always_inline sctp_connection_t *
614 sctp_get_connection_from_transport (transport_connection_t * tconn)
616 ASSERT (tconn != NULL);
618 sctp_sub_connection_t *sub = (sctp_sub_connection_t *) tconn;
621 SCTP_ADV_DBG ("sub == NULL");
622 if (sub->parent == NULL)
623 SCTP_ADV_DBG ("sub->parent == NULL");
625 if (sub->subconn_idx > 0)
626 return (sctp_connection_t *) sub -
627 (sizeof (sctp_sub_connection_t) * (sub->subconn_idx - 1));
629 return (sctp_connection_t *) sub;
635 return sctp_main.time_now[vlib_get_thread_index ()];
638 #define ABS(x) ((x) > 0) ? (x) : -(x);
641 sctp_calculate_rto (sctp_connection_t * sctp_conn, u8 conn_idx)
643 /* See RFC4960, 6.3.1. RTO Calculation */
646 u32 now = sctp_time_now ();
647 u32 prev_ts = sctp_conn->sub_conn[conn_idx].rtt_ts;
648 u32 R = prev_ts - now;
650 if (sctp_conn->sub_conn[conn_idx].RTO == 0) // C1: Let's initialize our RTO
652 sctp_conn->sub_conn[conn_idx].RTO = SCTP_RTO_MIN;
656 if (sctp_conn->sub_conn[conn_idx].RTO == SCTP_RTO_MIN && sctp_conn->sub_conn[conn_idx].SRTT == 0) // C2: First RTT calculation
658 sctp_conn->sub_conn[conn_idx].SRTT = R;
662 RTTVAR = 100e-3; /* 100 ms */
664 sctp_conn->sub_conn[conn_idx].RTTVAR = RTTVAR;
666 else // C3: RTT already exists; let's recalculate
668 RTTVAR = (1 - SCTP_RTO_BETA) * sctp_conn->sub_conn[conn_idx].RTTVAR +
669 SCTP_RTO_BETA * ABS (sctp_conn->sub_conn[conn_idx].SRTT - R);
672 RTTVAR = 100e-3; /* 100 ms */
674 sctp_conn->sub_conn[conn_idx].RTTVAR = RTTVAR;
676 sctp_conn->sub_conn[conn_idx].SRTT =
677 (1 - SCTP_RTO_ALPHA) * sctp_conn->sub_conn[conn_idx].SRTT +
682 sctp_conn->sub_conn[conn_idx].SRTT +
683 4 * sctp_conn->sub_conn[conn_idx].RTTVAR;
684 if (RTO < SCTP_RTO_MIN) // C6
687 if (RTO > SCTP_RTO_MAX) // C7
690 sctp_conn->sub_conn[conn_idx].RTO = RTO;
694 sctp_timer_update (sctp_connection_t * tc, u8 conn_idx, u8 timer_id,
697 ASSERT (tc->sub_conn[conn_idx].connection.thread_index ==
698 vlib_get_thread_index ());
699 sctp_sub_connection_t *sub = &tc->sub_conn[conn_idx];
701 if (tc->sub_conn[conn_idx].timers[timer_id] != SCTP_TIMER_HANDLE_INVALID)
702 tw_timer_stop_16t_2w_512sl (&sctp_main.timer_wheels[sub->c_thread_index],
703 sub->timers[timer_id]);
705 tc->sub_conn[conn_idx].timers[timer_id] =
706 tw_timer_start_16t_2w_512sl (&sctp_main.timer_wheels[sub->c_thread_index],
707 sub->c_c_index, timer_id, interval);
710 always_inline sctp_connection_t *
711 sctp_listener_get (u32 tli)
713 return pool_elt_at_index (sctp_main.listener_pool, tli);
718 always_inline sctp_connection_t *
719 sctp_connection_get (u32 conn_index, u32 thread_index)
722 (pool_is_free_index (sctp_main.connections[thread_index], conn_index)))
724 return pool_elt_at_index (sctp_main.connections[thread_index], conn_index);
727 #define SELECT_MAX_RETRIES 8
730 sctp_data_subconn_select (sctp_connection_t * sctp_conn)
732 u32 sub = MAIN_SCTP_SUB_CONN_IDX;
733 u8 i, cwnd = sctp_conn->sub_conn[MAIN_SCTP_SUB_CONN_IDX].cwnd;
734 for (i = 1; i < MAX_SCTP_CONNECTIONS; i++)
736 if (sctp_conn->sub_conn[i].state == SCTP_SUBCONN_STATE_DOWN)
739 if (sctp_conn->sub_conn[i].cwnd > cwnd)
742 cwnd = sctp_conn->sub_conn[i].cwnd;
749 sctp_sub_conn_id_via_ip6h (sctp_connection_t * sctp_conn, ip6_header_t * ip6h)
753 for (i = 0; i < MAX_SCTP_CONNECTIONS; i++)
755 if (sctp_conn->sub_conn[i].connection.lcl_ip.ip6.as_u64[0] ==
756 ip6h->dst_address.as_u64[0] &&
757 sctp_conn->sub_conn[i].connection.lcl_ip.ip6.as_u64[1] ==
758 ip6h->dst_address.as_u64[1] &&
759 sctp_conn->sub_conn[i].connection.rmt_ip.ip6.as_u64[0] ==
760 ip6h->src_address.as_u64[0] &&
761 sctp_conn->sub_conn[i].connection.rmt_ip.ip6.as_u64[1] ==
762 ip6h->src_address.as_u64[1])
765 clib_warning ("Did not find a sub-connection; defaulting to %u",
766 MAIN_SCTP_SUB_CONN_IDX);
767 return MAIN_SCTP_SUB_CONN_IDX;
771 sctp_sub_conn_id_via_ip4h (sctp_connection_t * sctp_conn, ip4_header_t * ip4h)
775 for (i = 0; i < MAX_SCTP_CONNECTIONS; i++)
777 if (sctp_conn->sub_conn[i].connection.lcl_ip.ip4.as_u32 ==
778 ip4h->dst_address.as_u32
779 && sctp_conn->sub_conn[i].connection.rmt_ip.ip4.as_u32 ==
780 ip4h->src_address.as_u32)
783 clib_warning ("Did not find a sub-connection; defaulting to %u",
784 MAIN_SCTP_SUB_CONN_IDX);
785 return MAIN_SCTP_SUB_CONN_IDX;
789 * Push SCTP header to buffer
791 * @param vm - vlib_main
792 * @param b - buffer to write the header to
793 * @param sp_net - source port net order
794 * @param dp_net - destination port net order
795 * @param sctp_hdr_opts_len - header and options length in bytes
797 * @return - pointer to start of SCTP header
800 vlib_buffer_push_sctp_net_order (vlib_buffer_t * b, u16 sp, u16 dp,
801 u8 sctp_hdr_opts_len)
803 sctp_full_hdr_t *full_hdr;
805 full_hdr = vlib_buffer_push_uninit (b, sctp_hdr_opts_len);
807 full_hdr->hdr.src_port = sp;
808 full_hdr->hdr.dst_port = dp;
809 full_hdr->hdr.checksum = 0;
814 * Push SCTP header to buffer
816 * @param b - buffer to write the header to
817 * @param sp_net - source port net order
818 * @param dp_net - destination port net order
819 * @param sctp_hdr_opts_len - header and options length in bytes
821 * @return - pointer to start of SCTP header
824 vlib_buffer_push_sctp (vlib_buffer_t * b, u16 sp_net, u16 dp_net,
825 u8 sctp_hdr_opts_len)
827 return vlib_buffer_push_sctp_net_order (b, sp_net, dp_net,
832 update_smallest_pmtu_idx (sctp_connection_t * sctp_conn)
835 u8 smallest_pmtu_index = MAIN_SCTP_SUB_CONN_IDX;
837 for (i = 1; i < MAX_SCTP_CONNECTIONS; i++)
839 if (sctp_conn->sub_conn[i].state != SCTP_SUBCONN_STATE_DOWN)
841 if (sctp_conn->sub_conn[i].PMTU <
842 sctp_conn->sub_conn[smallest_pmtu_index].PMTU)
843 smallest_pmtu_index = i;
847 sctp_conn->smallest_PMTU_idx = smallest_pmtu_index;
850 /* As per RFC4960; section 7.2.1: Slow-Start */
852 sctp_init_cwnd (sctp_connection_t * sctp_conn)
855 for (i = 0; i < MAX_SCTP_CONNECTIONS; i++)
857 /* Section 7.2.1; point (1) */
858 sctp_conn->sub_conn[i].cwnd =
859 clib_min (4 * sctp_conn->sub_conn[i].PMTU,
860 clib_max (2 * sctp_conn->sub_conn[i].PMTU, 4380));
862 /* Section 7.2.1; point (3) */
863 sctp_conn->sub_conn[i].ssthresh = SCTP_INITIAL_SSHTRESH;
865 /* Section 7.2.2; point (1) */
866 sctp_conn->sub_conn[i].partially_acked_bytes = 0;
871 sctp_in_cong_recovery (sctp_connection_t * sctp_conn, u8 idx)
877 cwnd_fully_utilized (sctp_connection_t * sctp_conn, u8 idx)
882 /* As per RFC4960; section 7.2.1: Slow-Start */
884 update_cwnd (sctp_connection_t * sctp_conn)
888 for (i = 0; i < MAX_SCTP_CONNECTIONS; i++)
890 /* Section 7.2.1; point (2) */
891 if (sctp_conn->sub_conn[i].is_retransmitting)
893 sctp_conn->sub_conn[i].cwnd = 1 * sctp_conn->sub_conn[i].PMTU;
897 /* Section 7.2.2; point (4) */
898 if (sctp_conn->sub_conn[i].last_data_ts >
899 sctp_time_now () + SCTP_DATA_IDLE_INTERVAL)
901 sctp_conn->sub_conn[i].cwnd =
902 clib_max (sctp_conn->sub_conn[i].cwnd / 2,
903 4 * sctp_conn->sub_conn[i].PMTU);
907 /* Section 7.2.1; point (5) */
908 if (sctp_conn->sub_conn[i].cwnd <= sctp_conn->sub_conn[i].ssthresh)
910 if (!cwnd_fully_utilized (sctp_conn, i))
913 if (sctp_in_cong_recovery (sctp_conn, i))
916 sctp_conn->sub_conn[i].cwnd =
917 clib_min (sctp_conn->sub_conn[i].PMTU, 1);
923 * fd.io coding-style-patch-verification: ON
926 * eval: (c-set-style "gnu")