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 */
242 typedef void (sctp_timer_expiration_handler) (u32 conn_index, u32 timer_id);
244 sctp_connection_t *sctp_connection_new (u8 thread_index);
245 void sctp_sub_connection_add_ip4 (u8 thread_index,
246 sctp_ipv4_addr_param_t * ipv4_addr);
247 void sctp_sub_connection_add_ip6 (u8 thread_index,
248 sctp_ipv6_addr_param_t * ipv6_addr);
249 void sctp_connection_close (sctp_connection_t * sctp_conn);
250 void sctp_connection_cleanup (sctp_connection_t * sctp_conn);
251 void sctp_connection_del (sctp_connection_t * sctp_conn);
253 u32 sctp_push_header (transport_connection_t * tconn, vlib_buffer_t * b);
254 void sctp_send_init (sctp_connection_t * sctp_conn);
255 void sctp_send_shutdown (sctp_connection_t * sctp_conn);
256 void sctp_send_shutdown_ack (sctp_connection_t * sctp_conn, u8 idx,
258 void sctp_send_shutdown_complete (sctp_connection_t * sctp_conn, u8 idx,
260 void sctp_send_heartbeat (sctp_connection_t * sctp_conn);
261 void sctp_flush_frame_to_output (vlib_main_t * vm, u8 thread_index,
263 void sctp_flush_frames_to_output (u8 thread_index);
264 void sctp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add);
266 format_function_t format_sctp_state;
268 u8 *format_sctp_connection_id (u8 * s, va_list * args);
269 u8 *format_sctp_connection (u8 * s, va_list * args);
270 u8 *format_sctp_scoreboard (u8 * s, va_list * args);
271 u8 *format_sctp_header (u8 * s, va_list * args);
272 u8 *format_sctp_tx_trace (u8 * s, va_list * args);
274 clib_error_t *sctp_init (vlib_main_t * vm);
275 void sctp_connection_timers_init (sctp_connection_t * sctp_conn);
276 void sctp_connection_timers_reset (sctp_connection_t * sctp_conn);
277 void sctp_init_snd_vars (sctp_connection_t * sctp_conn);
278 void sctp_init_mss (sctp_connection_t * sctp_conn);
280 void sctp_prepare_initack_chunk (sctp_connection_t * sctp_conn, u8 idx,
281 vlib_buffer_t * b, ip4_address_t * ip4_addr,
282 ip6_address_t * ip6_addr);
283 void sctp_prepare_cookie_echo_chunk (sctp_connection_t * sctp_conn, u8 idx,
285 sctp_state_cookie_param_t * sc);
286 void sctp_prepare_cookie_ack_chunk (sctp_connection_t * sctp_conn, u8 idx,
288 void sctp_prepare_sack_chunk (sctp_connection_t * sctp_conn, u8 idx,
290 void sctp_prepare_heartbeat_ack_chunk (sctp_connection_t * sctp_conn, u8 idx,
293 u16 sctp_check_outstanding_data_chunks (sctp_connection_t * sctp_conn);
295 #define IP_PROTOCOL_SCTP 132
297 /** SSCTP FSM state definitions as per RFC4960. */
298 #define foreach_sctp_fsm_state \
299 _(CLOSED, "CLOSED") \
300 _(COOKIE_WAIT, "COOKIE_WAIT") \
301 _(COOKIE_ECHOED, "COOKIE_ECHOED") \
302 _(ESTABLISHED, "ESTABLISHED") \
303 _(SHUTDOWN_PENDING, "SHUTDOWN_PENDING") \
304 _(SHUTDOWN_SENT, "SHUTDOWN_SENT") \
305 _(SHUTDOWN_RECEIVED, "SHUTDOWN_RECEIVED") \
306 _(SHUTDOWN_ACK_SENT, "SHUTDOWN_ACK_SENT")
308 typedef enum _sctp_state
310 #define _(sym, str) SCTP_STATE_##sym,
311 foreach_sctp_fsm_state
317 sctp_state_to_string (u8 state)
321 case SCTP_STATE_CLOSED:
322 return "SCTP_STATE_CLOSED";
323 case SCTP_STATE_COOKIE_WAIT:
324 return "SCTP_STATE_COOKIE_WAIT";
325 case SCTP_STATE_COOKIE_ECHOED:
326 return "SCTP_STATE_COOKIE_ECHOED";
327 case SCTP_STATE_ESTABLISHED:
328 return "SCTP_STATE_ESTABLISHED";
329 case SCTP_STATE_SHUTDOWN_PENDING:
330 return "SCTP_STATE_SHUTDOWN_PENDING";
331 case SCTP_STATE_SHUTDOWN_SENT:
332 return "SCTP_STATE_SHUTDOWN_SENT";
333 case SCTP_STATE_SHUTDOWN_RECEIVED:
334 return "SCTP_STATE_SHUTDOWN_RECEIVED";
335 case SCTP_STATE_SHUTDOWN_ACK_SENT:
336 return "SCTP_STATE_SHUTDOWN_ACK_SENT";
342 sctp_chunk_to_string (u8 type)
357 return "HEARTBEAT_ACK";
363 return "SHUTDOWN_ACK";
364 case OPERATION_ERROR:
365 return "OPERATION_ERROR";
367 return "COOKIE_ECHO";
374 case SHUTDOWN_COMPLETE:
375 return "SHUTDOWN_COMPLETE";
381 sctp_optparam_type_to_string (u8 type)
385 case SCTP_IPV4_ADDRESS_TYPE:
386 return "SCTP_IPV4_ADDRESS_TYPE";
387 case SCTP_IPV6_ADDRESS_TYPE:
388 return "SCTP_IPV6_ADDRESS_TYPE";
389 case SCTP_STATE_COOKIE_TYPE:
390 return "SCTP_STATE_COOKIE_TYPE";
391 case SCTP_UNRECOGNIZED_TYPE:
392 return "SCTP_UNRECOGNIZED_TYPE";
393 case SCTP_COOKIE_PRESERVATIVE_TYPE:
394 return "SCTP_COOKIE_PRESERVATIVE_TYPE";
395 case SCTP_HOSTNAME_ADDRESS_TYPE:
396 return "SCTP_HOSTNAME_ADDRESS_TYPE";
397 case SCTP_SUPPORTED_ADDRESS_TYPES:
398 return "SCTP_SUPPORTED_ADDRESS_TYPES";
403 #define SCTP_TICK 0.001 /**< SCTP tick period (s) */
404 #define SHZ (u32) (1/SCTP_TICK) /**< SCTP tick frequency */
405 #define SCTP_TSTAMP_RESOLUTION SCTP_TICK /**< Time stamp resolution */
407 /* As per RFC4960, page 83 */
408 #define SCTP_RTO_INIT 3 * SHZ /* 3 seconds */
409 #define SCTP_RTO_MIN 1 * SHZ /* 1 second */
410 #define SCTP_RTO_MAX 60 * SHZ /* 60 seconds */
411 #define SCTP_RTO_BURST 4
412 #define SCTP_RTO_ALPHA 1/8
413 #define SCTP_RTO_BETA 1/4
414 #define SCTP_VALID_COOKIE_LIFE 60 * SHZ /* 60 seconds */
415 #define SCTP_ASSOCIATION_MAX_RETRANS 10 // the overall connection
416 #define SCTP_PATH_MAX_RETRANS 5 // number of attempts per destination address
417 #define SCTP_MAX_INIT_RETRANS 8 // number of attempts
418 #define SCTP_HB_INTERVAL 30 * SHZ
419 #define SCTP_HB_MAX_BURST 1
421 #define SCTP_DATA_IDLE_INTERVAL 15 * SHZ /* 15 seconds; the time-interval after which the connetion is considered IDLE */
423 #define SCTP_TO_TIMER_TICK SCTP_TICK*10 /* Period for converting from SCTP_TICK */
425 typedef struct _sctp_lookup_dispatch
428 } sctp_lookup_dispatch_t;
430 typedef struct _sctp_main
432 /* Per-worker thread SCTP connection pools */
433 sctp_connection_t **connections;
435 /* Pool of listeners. */
436 sctp_connection_t *listener_pool;
438 /** Dispatch table by state and flags */
439 sctp_lookup_dispatch_t dispatch_table[SCTP_N_STATES][64];
441 u8 log2_tstamp_clocks_per_tick;
442 f64 tstamp_ticks_per_clock;
445 /** per-worker tx buffer free lists */
447 /** per-worker tx frames to SCTP 4/6 output nodes */
448 vlib_frame_t **tx_frames[2];
449 /** per-worker tx frames to ip 4/6 lookup nodes */
450 vlib_frame_t **ip_lookup_tx_frames[2];
452 /* Per worker-thread timer wheel for connections timers */
453 tw_timer_wheel_16t_2w_512sl_t *timer_wheels;
455 /* Pool of half-open connections on which we've sent a SYN */
456 sctp_connection_t *half_open_connections;
457 clib_spinlock_t half_open_lock;
459 /* TODO: Congestion control algorithms registered */
460 /* sctp_cc_algorithm_t *cc_algos; */
462 /* Flag that indicates if stack is on or off */
465 /** Number of preallocated connections */
466 u32 preallocated_connections;
468 /** Transport table (preallocation) size parameters */
469 u32 local_endpoints_table_memory;
470 u32 local_endpoints_table_buckets;
472 /** Vectors of src addresses. Optional unless one needs > 63K active-opens */
473 ip4_address_t *ip4_src_addresses;
474 u32 last_v4_address_rotor;
475 u32 last_v6_address_rotor;
476 ip6_address_t *ip6_src_addresses;
478 /** vlib buffer size */
479 u32 bytes_per_buffer;
486 extern sctp_main_t sctp_main;
487 extern vlib_node_registration_t sctp4_input_node;
488 extern vlib_node_registration_t sctp6_input_node;
489 extern vlib_node_registration_t sctp4_output_node;
490 extern vlib_node_registration_t sctp6_output_node;
492 always_inline sctp_main_t *
493 vnet_get_sctp_main ()
498 always_inline sctp_header_t *
499 sctp_buffer_hdr (vlib_buffer_t * b)
501 ASSERT ((signed) b->current_data >= (signed) -VLIB_BUFFER_PRE_DATA_SIZE);
502 return (sctp_header_t *) (b->data + b->current_data
503 + vnet_buffer (b)->sctp.hdr_offset);
506 clib_error_t *vnet_sctp_enable_disable (vlib_main_t * vm, u8 is_en);
508 always_inline sctp_connection_t *
509 sctp_half_open_connection_get (u32 conn_index)
511 sctp_connection_t *tc = 0;
512 clib_spinlock_lock_if_init (&sctp_main.half_open_lock);
513 if (!pool_is_free_index (sctp_main.half_open_connections, conn_index))
514 tc = pool_elt_at_index (sctp_main.half_open_connections, conn_index);
515 tc->sub_conn[MAIN_SCTP_SUB_CONN_IDX].subconn_idx = MAIN_SCTP_SUB_CONN_IDX;
516 clib_spinlock_unlock_if_init (&sctp_main.half_open_lock);
521 * Cleanup half-open connection
525 sctp_half_open_connection_del (sctp_connection_t * tc)
527 sctp_main_t *sctp_main = vnet_get_sctp_main ();
528 clib_spinlock_lock_if_init (&sctp_main->half_open_lock);
529 pool_put_index (sctp_main->half_open_connections,
530 tc->sub_conn[MAIN_SCTP_SUB_CONN_IDX].c_c_index);
532 memset (tc, 0xFA, sizeof (*tc));
533 clib_spinlock_unlock_if_init (&sctp_main->half_open_lock);
537 sctp_set_time_now (u32 thread_index)
539 sctp_main.time_now[thread_index] = clib_cpu_time_now ()
540 * sctp_main.tstamp_ticks_per_clock;
541 return sctp_main.time_now[thread_index];
545 sctp_timer_set (sctp_connection_t * tc, u8 conn_idx, u8 timer_id,
548 ASSERT (tc->sub_conn[conn_idx].connection.thread_index ==
549 vlib_get_thread_index ());
550 ASSERT (tc->sub_conn[conn_idx].timers[timer_id] ==
551 SCTP_TIMER_HANDLE_INVALID);
553 sctp_sub_connection_t *sub = &tc->sub_conn[conn_idx];
554 sub->timers[timer_id] =
555 tw_timer_start_16t_2w_512sl (&sctp_main.timer_wheels[sub->c_thread_index],
556 sub->c_c_index, timer_id, interval);
560 sctp_timer_reset (sctp_connection_t * tc, u8 conn_idx, u8 timer_id)
562 ASSERT (tc->sub_conn[conn_idx].c_thread_index == vlib_get_thread_index ());
563 if (tc->sub_conn[conn_idx].timers[timer_id] == SCTP_TIMER_HANDLE_INVALID)
566 sctp_sub_connection_t *sub = &tc->sub_conn[conn_idx];
568 tw_timer_stop_16t_2w_512sl (&sctp_main.timer_wheels[sub->c_thread_index],
569 sub->timers[timer_id]);
570 sub->timers[timer_id] = SCTP_TIMER_HANDLE_INVALID;
574 * Try to cleanup half-open connection
576 * If called from a thread that doesn't own tc, the call won't have any
579 * @param tc - connection to be cleaned up
580 * @return non-zero if cleanup failed.
583 sctp_half_open_connection_cleanup (sctp_connection_t * tc)
585 /* Make sure this is the owning thread */
586 if (tc->sub_conn[MAIN_SCTP_SUB_CONN_IDX].c_thread_index !=
587 vlib_get_thread_index ())
589 sctp_timer_reset (tc, MAIN_SCTP_SUB_CONN_IDX, SCTP_TIMER_T1_INIT);
590 sctp_half_open_connection_del (tc);
597 return sizeof (sctp_header_t);
600 always_inline sctp_connection_t *
601 sctp_get_connection_from_transport (transport_connection_t * tconn)
603 ASSERT (tconn != NULL);
605 sctp_sub_connection_t *sub = (sctp_sub_connection_t *) tconn;
608 SCTP_ADV_DBG ("sub == NULL");
609 if (sub->parent == NULL)
610 SCTP_ADV_DBG ("sub->parent == NULL");
612 if (sub->subconn_idx > 0)
613 return (sctp_connection_t *) sub -
614 (sizeof (sctp_sub_connection_t) * (sub->subconn_idx - 1));
616 return (sctp_connection_t *) sub;
622 return sctp_main.time_now[vlib_get_thread_index ()];
625 #define ABS(x) ((x) > 0) ? (x) : -(x);
628 sctp_calculate_rto (sctp_connection_t * sctp_conn, u8 conn_idx)
630 /* See RFC4960, 6.3.1. RTO Calculation */
633 u32 now = sctp_time_now ();
634 u32 prev_ts = sctp_conn->sub_conn[conn_idx].rtt_ts;
635 u32 R = prev_ts - now;
637 if (sctp_conn->sub_conn[conn_idx].RTO == 0) // C1: Let's initialize our RTO
639 sctp_conn->sub_conn[conn_idx].RTO = SCTP_RTO_MIN;
643 if (sctp_conn->sub_conn[conn_idx].RTO == SCTP_RTO_MIN && sctp_conn->sub_conn[conn_idx].SRTT == 0) // C2: First RTT calculation
645 sctp_conn->sub_conn[conn_idx].SRTT = R;
649 RTTVAR = 100e-3; /* 100 ms */
651 sctp_conn->sub_conn[conn_idx].RTTVAR = RTTVAR;
653 else // C3: RTT already exists; let's recalculate
655 RTTVAR = (1 - SCTP_RTO_BETA) * sctp_conn->sub_conn[conn_idx].RTTVAR +
656 SCTP_RTO_BETA * ABS (sctp_conn->sub_conn[conn_idx].SRTT - R);
659 RTTVAR = 100e-3; /* 100 ms */
661 sctp_conn->sub_conn[conn_idx].RTTVAR = RTTVAR;
663 sctp_conn->sub_conn[conn_idx].SRTT =
664 (1 - SCTP_RTO_ALPHA) * sctp_conn->sub_conn[conn_idx].SRTT +
669 sctp_conn->sub_conn[conn_idx].SRTT +
670 4 * sctp_conn->sub_conn[conn_idx].RTTVAR;
671 if (RTO < SCTP_RTO_MIN) // C6
674 if (RTO > SCTP_RTO_MAX) // C7
677 sctp_conn->sub_conn[conn_idx].RTO = RTO;
681 sctp_timer_update (sctp_connection_t * tc, u8 conn_idx, u8 timer_id,
684 ASSERT (tc->sub_conn[conn_idx].connection.thread_index ==
685 vlib_get_thread_index ());
686 sctp_sub_connection_t *sub = &tc->sub_conn[conn_idx];
688 if (tc->sub_conn[conn_idx].timers[timer_id] != SCTP_TIMER_HANDLE_INVALID)
689 tw_timer_stop_16t_2w_512sl (&sctp_main.timer_wheels[sub->c_thread_index],
690 sub->timers[timer_id]);
692 tc->sub_conn[conn_idx].timers[timer_id] =
693 tw_timer_start_16t_2w_512sl (&sctp_main.timer_wheels[sub->c_thread_index],
694 sub->c_c_index, timer_id, interval);
697 always_inline sctp_connection_t *
698 sctp_listener_get (u32 tli)
700 return pool_elt_at_index (sctp_main.listener_pool, tli);
705 always_inline sctp_connection_t *
706 sctp_connection_get (u32 conn_index, u32 thread_index)
709 (pool_is_free_index (sctp_main.connections[thread_index], conn_index)))
711 return pool_elt_at_index (sctp_main.connections[thread_index], conn_index);
714 #define SELECT_MAX_RETRIES 8
717 sctp_data_subconn_select (sctp_connection_t * sctp_conn)
719 u32 sub = MAIN_SCTP_SUB_CONN_IDX;
720 u8 i, cwnd = sctp_conn->sub_conn[MAIN_SCTP_SUB_CONN_IDX].cwnd;
721 for (i = 1; i < MAX_SCTP_CONNECTIONS; i++)
723 if (sctp_conn->sub_conn[i].state == SCTP_SUBCONN_STATE_DOWN)
726 if (sctp_conn->sub_conn[i].cwnd > cwnd)
729 cwnd = sctp_conn->sub_conn[i].cwnd;
736 sctp_sub_conn_id_via_ip6h (sctp_connection_t * sctp_conn, ip6_header_t * ip6h)
740 for (i = 0; i < MAX_SCTP_CONNECTIONS; i++)
742 if (sctp_conn->sub_conn[i].connection.lcl_ip.ip6.as_u64[0] ==
743 ip6h->dst_address.as_u64[0] &&
744 sctp_conn->sub_conn[i].connection.lcl_ip.ip6.as_u64[1] ==
745 ip6h->dst_address.as_u64[1] &&
746 sctp_conn->sub_conn[i].connection.rmt_ip.ip6.as_u64[0] ==
747 ip6h->src_address.as_u64[0] &&
748 sctp_conn->sub_conn[i].connection.rmt_ip.ip6.as_u64[1] ==
749 ip6h->src_address.as_u64[1])
752 clib_warning ("Did not find a sub-connection; defaulting to %u",
753 MAIN_SCTP_SUB_CONN_IDX);
754 return MAIN_SCTP_SUB_CONN_IDX;
758 sctp_sub_conn_id_via_ip4h (sctp_connection_t * sctp_conn, ip4_header_t * ip4h)
762 for (i = 0; i < MAX_SCTP_CONNECTIONS; i++)
764 if (sctp_conn->sub_conn[i].connection.lcl_ip.ip4.as_u32 ==
765 ip4h->dst_address.as_u32
766 && sctp_conn->sub_conn[i].connection.rmt_ip.ip4.as_u32 ==
767 ip4h->src_address.as_u32)
770 clib_warning ("Did not find a sub-connection; defaulting to %u",
771 MAIN_SCTP_SUB_CONN_IDX);
772 return MAIN_SCTP_SUB_CONN_IDX;
776 * Push SCTP header to buffer
778 * @param vm - vlib_main
779 * @param b - buffer to write the header to
780 * @param sp_net - source port net order
781 * @param dp_net - destination port net order
782 * @param sctp_hdr_opts_len - header and options length in bytes
784 * @return - pointer to start of SCTP header
787 vlib_buffer_push_sctp_net_order (vlib_buffer_t * b, u16 sp, u16 dp,
788 u8 sctp_hdr_opts_len)
790 sctp_full_hdr_t *full_hdr;
792 full_hdr = vlib_buffer_push_uninit (b, sctp_hdr_opts_len);
794 full_hdr->hdr.src_port = sp;
795 full_hdr->hdr.dst_port = dp;
796 full_hdr->hdr.checksum = 0;
801 * Push SCTP header to buffer
803 * @param b - buffer to write the header to
804 * @param sp_net - source port net order
805 * @param dp_net - destination port net order
806 * @param sctp_hdr_opts_len - header and options length in bytes
808 * @return - pointer to start of SCTP header
811 vlib_buffer_push_sctp (vlib_buffer_t * b, u16 sp_net, u16 dp_net,
812 u8 sctp_hdr_opts_len)
814 return vlib_buffer_push_sctp_net_order (b, sp_net, dp_net,
819 update_smallest_pmtu_idx (sctp_connection_t * sctp_conn)
822 u8 smallest_pmtu_index = MAIN_SCTP_SUB_CONN_IDX;
824 for (i = 1; i < MAX_SCTP_CONNECTIONS; i++)
826 if (sctp_conn->sub_conn[i].state != SCTP_SUBCONN_STATE_DOWN)
828 if (sctp_conn->sub_conn[i].PMTU <
829 sctp_conn->sub_conn[smallest_pmtu_index].PMTU)
830 smallest_pmtu_index = i;
834 sctp_conn->smallest_PMTU_idx = smallest_pmtu_index;
837 /* As per RFC4960; section 7.2.1: Slow-Start */
839 sctp_init_cwnd (sctp_connection_t * sctp_conn)
842 for (i = 0; i < MAX_SCTP_CONNECTIONS; i++)
844 /* Section 7.2.1; point (1) */
845 sctp_conn->sub_conn[i].cwnd =
846 clib_min (4 * sctp_conn->sub_conn[i].PMTU,
847 clib_max (2 * sctp_conn->sub_conn[i].PMTU, 4380));
849 /* Section 7.2.1; point (3) */
850 sctp_conn->sub_conn[i].ssthresh = SCTP_INITIAL_SSHTRESH;
852 /* Section 7.2.2; point (1) */
853 sctp_conn->sub_conn[i].partially_acked_bytes = 0;
858 sctp_in_cong_recovery (sctp_connection_t * sctp_conn, u8 idx)
864 cwnd_fully_utilized (sctp_connection_t * sctp_conn, u8 idx)
869 /* As per RFC4960; section 7.2.1: Slow-Start */
871 update_cwnd (sctp_connection_t * sctp_conn)
875 for (i = 0; i < MAX_SCTP_CONNECTIONS; i++)
877 /* Section 7.2.1; point (2) */
878 if (sctp_conn->sub_conn[i].is_retransmitting)
880 sctp_conn->sub_conn[i].cwnd = 1 * sctp_conn->sub_conn[i].PMTU;
884 /* Section 7.2.2; point (4) */
885 if (sctp_conn->sub_conn[i].last_data_ts >
886 sctp_time_now () + SCTP_DATA_IDLE_INTERVAL)
888 sctp_conn->sub_conn[i].cwnd =
889 clib_max (sctp_conn->sub_conn[i].cwnd / 2,
890 4 * sctp_conn->sub_conn[i].PMTU);
894 /* Section 7.2.1; point (5) */
895 if (sctp_conn->sub_conn[i].cwnd <= sctp_conn->sub_conn[i].ssthresh)
897 if (!cwnd_fully_utilized (sctp_conn, i))
900 if (sctp_in_cong_recovery (sctp_conn, i))
903 sctp_conn->sub_conn[i].cwnd =
904 clib_min (sctp_conn->sub_conn[i].PMTU, 1);
910 * fd.io coding-style-patch-verification: ON
913 * eval: (c-set-style "gnu")