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 u8 init_retransmit_err; /**< Error counter for the INIT transmission phase */
205 u32 peer_rwnd; /**< Current calculated value of the peer's rwnd. */
207 u32 next_tsn; /**< The next TSN number to be assigned to a new DATA chunk.
208 This is sent in the INIT or INIT ACK chunk to the peer
209 and incremented each time a DATA chunk is assigned a
210 TSN (normally just prior to transmit or during
213 u32 last_unacked_tsn; /** < Last TSN number still unacked */
214 u32 next_tsn_expected; /**< The next TSN number expected to be received. */
216 u32 last_rcvd_tsn; /**< This is the last TSN received in sequence. This value
217 is set initially by taking the peer's initial TSN,
218 received in the INIT or INIT ACK chunk, and
219 subtracting one from it. */
221 u32 out_of_order_map[MAX_INFLIGHT_PACKETS]; /**< An array of bits or bytes indicating which out-of-order
222 TSNs have been received (relative to the Last Rcvd TSN).
223 If no gaps exist, i.e., no out-of-order packets have been received,
224 this array will be set to all zero. */
226 u8 ack_state; /**< This flag indicates if the next received packet is set to be responded to with a SACK.
227 This is initialized to 0. When a packet is received it is incremented.
228 If this value reaches 2 or more, a SACK is sent and the value is reset to 0.
229 Note: This is used only when no DATA chunks are received out-of-order.
230 When DATA chunks are out-of-order, SACKs are not delayed (see Section 6). */
232 u8 smallest_PMTU_idx; /** The index of the sub-connection with the smallest PMTU discovered across all peer's transport addresses. */
234 u8 overall_sending_status; /**< 0 indicates first fragment of a user message
235 1 indicates normal stream
236 2 indicates last fragment of a user message */
238 u8 forming_association_changed; /**< This is a flag indicating whether the original association has been modified during
239 the life-span of the association itself. For instance, a new sub-connection might have been added. */
241 sctp_state_cookie_param_t cookie_param; /**< Temporary location to save cookie information; it can be used to
242 when timeout expires and sending again a COOKIE is require. */
246 typedef void (sctp_timer_expiration_handler) (u32 conn_index, u32 timer_id);
248 sctp_connection_t *sctp_connection_new (u8 thread_index);
251 sctp_sub_connection_add_ip4 (vlib_main_t * vm,
252 ip4_address_t * lcl_addr,
253 ip4_address_t * rmt_addr);
256 sctp_sub_connection_add_ip6 (vlib_main_t * vm,
257 ip6_address_t * lcl_addr,
258 ip6_address_t * rmt_addr);
261 sctp_sub_connection_del_ip4 (ip4_address_t * lcl_addr,
262 ip4_address_t * rmt_addr);
265 sctp_sub_connection_del_ip6 (ip6_address_t * lcl_addr,
266 ip6_address_t * rmt_addr);
268 void sctp_connection_close (sctp_connection_t * sctp_conn);
269 void sctp_connection_cleanup (sctp_connection_t * sctp_conn);
270 void sctp_connection_del (sctp_connection_t * sctp_conn);
272 u32 sctp_push_header (transport_connection_t * tconn, vlib_buffer_t * b);
273 void sctp_send_init (sctp_connection_t * sctp_conn);
274 void sctp_send_cookie_echo (sctp_connection_t * sctp_conn);
275 void sctp_send_shutdown (sctp_connection_t * sctp_conn);
276 void sctp_send_shutdown_ack (sctp_connection_t * sctp_conn, u8 idx,
278 void sctp_send_shutdown_complete (sctp_connection_t * sctp_conn, u8 idx,
280 void sctp_send_heartbeat (sctp_connection_t * sctp_conn);
281 void sctp_data_retransmit (sctp_connection_t * sctp_conn);
282 void sctp_flush_frame_to_output (vlib_main_t * vm, u8 thread_index,
284 void sctp_flush_frames_to_output (u8 thread_index);
285 void sctp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add);
287 format_function_t format_sctp_state;
289 u8 *format_sctp_connection_id (u8 * s, va_list * args);
290 u8 *format_sctp_connection (u8 * s, va_list * args);
291 u8 *format_sctp_scoreboard (u8 * s, va_list * args);
292 u8 *format_sctp_header (u8 * s, va_list * args);
293 u8 *format_sctp_tx_trace (u8 * s, va_list * args);
295 clib_error_t *sctp_init (vlib_main_t * vm);
296 void sctp_connection_timers_init (sctp_connection_t * sctp_conn);
297 void sctp_connection_timers_reset (sctp_connection_t * sctp_conn);
298 void sctp_init_snd_vars (sctp_connection_t * sctp_conn);
299 void sctp_init_mss (sctp_connection_t * sctp_conn);
301 void sctp_prepare_initack_chunk (sctp_connection_t * sctp_conn, u8 idx,
302 vlib_buffer_t * b, ip4_address_t * ip4_addr,
303 ip6_address_t * ip6_addr);
305 sctp_prepare_initack_chunk_for_collision (sctp_connection_t * sctp_conn,
306 u8 idx, vlib_buffer_t * b,
307 ip4_address_t * ip4_addr,
308 ip6_address_t * ip6_addr);
309 void sctp_prepare_abort_for_collision (sctp_connection_t * sctp_conn, u8 idx,
311 ip4_address_t * ip4_addr,
312 ip6_address_t * ip6_addr);
314 sctp_prepare_operation_error (sctp_connection_t * sctp_conn, u8 idx,
315 vlib_buffer_t * b, u8 err_cause);
316 void sctp_prepare_cookie_echo_chunk (sctp_connection_t * sctp_conn, u8 idx,
317 vlib_buffer_t * b, u8 reuse_buffer);
318 void sctp_prepare_cookie_ack_chunk (sctp_connection_t * sctp_conn, u8 idx,
320 void sctp_prepare_sack_chunk (sctp_connection_t * sctp_conn, u8 idx,
322 void sctp_prepare_heartbeat_ack_chunk (sctp_connection_t * sctp_conn, u8 idx,
325 u16 sctp_check_outstanding_data_chunks (sctp_connection_t * sctp_conn);
327 void sctp_api_reference (void);
329 #define IP_PROTOCOL_SCTP 132
331 /** SSCTP FSM state definitions as per RFC4960. */
332 #define foreach_sctp_fsm_state \
333 _(CLOSED, "CLOSED") \
334 _(COOKIE_WAIT, "COOKIE_WAIT") \
335 _(COOKIE_ECHOED, "COOKIE_ECHOED") \
336 _(ESTABLISHED, "ESTABLISHED") \
337 _(SHUTDOWN_PENDING, "SHUTDOWN_PENDING") \
338 _(SHUTDOWN_SENT, "SHUTDOWN_SENT") \
339 _(SHUTDOWN_RECEIVED, "SHUTDOWN_RECEIVED") \
340 _(SHUTDOWN_ACK_SENT, "SHUTDOWN_ACK_SENT")
342 typedef enum _sctp_state
344 #define _(sym, str) SCTP_STATE_##sym,
345 foreach_sctp_fsm_state
351 sctp_state_to_string (u8 state)
355 case SCTP_STATE_CLOSED:
356 return "SCTP_STATE_CLOSED";
357 case SCTP_STATE_COOKIE_WAIT:
358 return "SCTP_STATE_COOKIE_WAIT";
359 case SCTP_STATE_COOKIE_ECHOED:
360 return "SCTP_STATE_COOKIE_ECHOED";
361 case SCTP_STATE_ESTABLISHED:
362 return "SCTP_STATE_ESTABLISHED";
363 case SCTP_STATE_SHUTDOWN_PENDING:
364 return "SCTP_STATE_SHUTDOWN_PENDING";
365 case SCTP_STATE_SHUTDOWN_SENT:
366 return "SCTP_STATE_SHUTDOWN_SENT";
367 case SCTP_STATE_SHUTDOWN_RECEIVED:
368 return "SCTP_STATE_SHUTDOWN_RECEIVED";
369 case SCTP_STATE_SHUTDOWN_ACK_SENT:
370 return "SCTP_STATE_SHUTDOWN_ACK_SENT";
376 sctp_chunk_to_string (u8 type)
391 return "HEARTBEAT_ACK";
397 return "SHUTDOWN_ACK";
398 case OPERATION_ERROR:
399 return "OPERATION_ERROR";
401 return "COOKIE_ECHO";
408 case SHUTDOWN_COMPLETE:
409 return "SHUTDOWN_COMPLETE";
415 sctp_optparam_type_to_string (u8 type)
419 case SCTP_IPV4_ADDRESS_TYPE:
420 return "SCTP_IPV4_ADDRESS_TYPE";
421 case SCTP_IPV6_ADDRESS_TYPE:
422 return "SCTP_IPV6_ADDRESS_TYPE";
423 case SCTP_STATE_COOKIE_TYPE:
424 return "SCTP_STATE_COOKIE_TYPE";
425 case SCTP_UNRECOGNIZED_TYPE:
426 return "SCTP_UNRECOGNIZED_TYPE";
427 case SCTP_COOKIE_PRESERVATIVE_TYPE:
428 return "SCTP_COOKIE_PRESERVATIVE_TYPE";
429 case SCTP_HOSTNAME_ADDRESS_TYPE:
430 return "SCTP_HOSTNAME_ADDRESS_TYPE";
431 case SCTP_SUPPORTED_ADDRESS_TYPES:
432 return "SCTP_SUPPORTED_ADDRESS_TYPES";
437 #define SCTP_TICK 0.001 /**< SCTP tick period (s) */
438 #define SHZ (u32) (1/SCTP_TICK) /**< SCTP tick frequency */
439 #define SCTP_TSTAMP_RESOLUTION SCTP_TICK /**< Time stamp resolution */
441 /* As per RFC4960, page 83 */
442 #define SCTP_RTO_INIT 3 * SHZ /* 3 seconds */
443 #define SCTP_RTO_MIN 1 * SHZ /* 1 second */
444 #define SCTP_RTO_MAX 60 * SHZ /* 60 seconds */
445 #define SCTP_RTO_BURST 4
446 #define SCTP_RTO_ALPHA 1/8
447 #define SCTP_RTO_BETA 1/4
448 #define SCTP_VALID_COOKIE_LIFE 60 * SHZ /* 60 seconds */
449 #define SCTP_ASSOCIATION_MAX_RETRANS 10 // the overall connection
450 #define SCTP_PATH_MAX_RETRANS 5 // number of attempts per destination address
451 #define SCTP_MAX_INIT_RETRANS 8 // number of attempts
452 #define SCTP_HB_INTERVAL 30 * SHZ
453 #define SCTP_HB_MAX_BURST 1
455 #define SCTP_DATA_IDLE_INTERVAL 15 * SHZ /* 15 seconds; the time-interval after which the connetion is considered IDLE */
457 #define SCTP_TO_TIMER_TICK SCTP_TICK*10 /* Period for converting from SCTP_TICK */
459 typedef struct _sctp_lookup_dispatch
462 } sctp_lookup_dispatch_t;
464 typedef struct _sctp_main
466 /* Per-worker thread SCTP connection pools */
467 sctp_connection_t **connections;
469 /* Pool of listeners. */
470 sctp_connection_t *listener_pool;
472 /** Dispatch table by state and flags */
473 sctp_lookup_dispatch_t dispatch_table[SCTP_N_STATES][64];
475 u8 log2_tstamp_clocks_per_tick;
476 f64 tstamp_ticks_per_clock;
479 /** per-worker tx buffer free lists */
481 /** per-worker tx frames to SCTP 4/6 output nodes */
482 vlib_frame_t **tx_frames[2];
483 /** per-worker tx frames to ip 4/6 lookup nodes */
484 vlib_frame_t **ip_lookup_tx_frames[2];
486 /* Per worker-thread timer wheel for connections timers */
487 tw_timer_wheel_16t_2w_512sl_t *timer_wheels;
489 /* Pool of half-open connections on which we've sent a SYN */
490 sctp_connection_t *half_open_connections;
491 clib_spinlock_t half_open_lock;
493 /* TODO: Congestion control algorithms registered */
494 /* sctp_cc_algorithm_t *cc_algos; */
496 /* Flag that indicates if stack is on or off */
499 /** Number of preallocated connections */
500 u32 preallocated_connections;
502 /** Transport table (preallocation) size parameters */
503 u32 local_endpoints_table_memory;
504 u32 local_endpoints_table_buckets;
506 /** Vectors of src addresses. Optional unless one needs > 63K active-opens */
507 ip4_address_t *ip4_src_addresses;
508 u32 last_v4_address_rotor;
509 u32 last_v6_address_rotor;
510 ip6_address_t *ip6_src_addresses;
512 /** vlib buffer size */
513 u32 bytes_per_buffer;
520 extern sctp_main_t sctp_main;
521 extern vlib_node_registration_t sctp4_input_node;
522 extern vlib_node_registration_t sctp6_input_node;
523 extern vlib_node_registration_t sctp4_output_node;
524 extern vlib_node_registration_t sctp6_output_node;
526 always_inline sctp_main_t *
527 vnet_get_sctp_main ()
532 always_inline sctp_header_t *
533 sctp_buffer_hdr (vlib_buffer_t * b)
535 ASSERT ((signed) b->current_data >= (signed) -VLIB_BUFFER_PRE_DATA_SIZE);
536 return (sctp_header_t *) (b->data + b->current_data
537 + vnet_buffer (b)->sctp.hdr_offset);
540 clib_error_t *vnet_sctp_enable_disable (vlib_main_t * vm, u8 is_en);
542 always_inline sctp_connection_t *
543 sctp_half_open_connection_get (u32 conn_index)
545 sctp_connection_t *tc = 0;
546 clib_spinlock_lock_if_init (&sctp_main.half_open_lock);
547 if (!pool_is_free_index (sctp_main.half_open_connections, conn_index))
548 tc = pool_elt_at_index (sctp_main.half_open_connections, conn_index);
549 tc->sub_conn[MAIN_SCTP_SUB_CONN_IDX].subconn_idx = MAIN_SCTP_SUB_CONN_IDX;
550 clib_spinlock_unlock_if_init (&sctp_main.half_open_lock);
555 * Cleanup half-open connection
559 sctp_half_open_connection_del (sctp_connection_t * tc)
561 sctp_main_t *sctp_main = vnet_get_sctp_main ();
562 clib_spinlock_lock_if_init (&sctp_main->half_open_lock);
563 pool_put_index (sctp_main->half_open_connections,
564 tc->sub_conn[MAIN_SCTP_SUB_CONN_IDX].c_c_index);
566 memset (tc, 0xFA, sizeof (*tc));
567 clib_spinlock_unlock_if_init (&sctp_main->half_open_lock);
571 sctp_set_time_now (u32 thread_index)
573 sctp_main.time_now[thread_index] = clib_cpu_time_now ()
574 * sctp_main.tstamp_ticks_per_clock;
575 return sctp_main.time_now[thread_index];
579 sctp_timer_set (sctp_connection_t * tc, u8 conn_idx, u8 timer_id,
582 ASSERT (tc->sub_conn[conn_idx].connection.thread_index ==
583 vlib_get_thread_index ());
584 ASSERT (tc->sub_conn[conn_idx].timers[timer_id] ==
585 SCTP_TIMER_HANDLE_INVALID);
587 sctp_sub_connection_t *sub = &tc->sub_conn[conn_idx];
588 sub->timers[timer_id] =
589 tw_timer_start_16t_2w_512sl (&sctp_main.timer_wheels[sub->c_thread_index],
590 sub->c_c_index, timer_id, interval);
594 sctp_timer_reset (sctp_connection_t * tc, u8 conn_idx, u8 timer_id)
596 ASSERT (tc->sub_conn[conn_idx].c_thread_index == vlib_get_thread_index ());
597 if (tc->sub_conn[conn_idx].timers[timer_id] == SCTP_TIMER_HANDLE_INVALID)
600 sctp_sub_connection_t *sub = &tc->sub_conn[conn_idx];
602 tw_timer_stop_16t_2w_512sl (&sctp_main.timer_wheels[sub->c_thread_index],
603 sub->timers[timer_id]);
604 sub->timers[timer_id] = SCTP_TIMER_HANDLE_INVALID;
608 * Try to cleanup half-open connection
610 * If called from a thread that doesn't own tc, the call won't have any
613 * @param tc - connection to be cleaned up
614 * @return non-zero if cleanup failed.
617 sctp_half_open_connection_cleanup (sctp_connection_t * tc)
619 /* Make sure this is the owning thread */
620 if (tc->sub_conn[MAIN_SCTP_SUB_CONN_IDX].c_thread_index !=
621 vlib_get_thread_index ())
623 sctp_timer_reset (tc, MAIN_SCTP_SUB_CONN_IDX, SCTP_TIMER_T1_INIT);
624 sctp_half_open_connection_del (tc);
631 return sizeof (sctp_header_t);
634 always_inline sctp_connection_t *
635 sctp_get_connection_from_transport (transport_connection_t * tconn)
637 ASSERT (tconn != NULL);
639 sctp_sub_connection_t *sub = (sctp_sub_connection_t *) tconn;
642 SCTP_ADV_DBG ("sub == NULL");
643 if (sub->parent == NULL)
644 SCTP_ADV_DBG ("sub->parent == NULL");
646 if (sub->subconn_idx > 0)
647 return (sctp_connection_t *) sub -
648 (sizeof (sctp_sub_connection_t) * (sub->subconn_idx - 1));
650 return (sctp_connection_t *) sub;
656 return sctp_main.time_now[vlib_get_thread_index ()];
659 #define ABS(x) ((x) > 0) ? (x) : -(x);
662 sctp_calculate_rto (sctp_connection_t * sctp_conn, u8 conn_idx)
664 /* See RFC4960, 6.3.1. RTO Calculation */
667 u32 now = sctp_time_now ();
668 u32 prev_ts = sctp_conn->sub_conn[conn_idx].rtt_ts;
669 u32 R = prev_ts - now;
671 if (sctp_conn->sub_conn[conn_idx].RTO == 0) // C1: Let's initialize our RTO
673 sctp_conn->sub_conn[conn_idx].RTO = SCTP_RTO_MIN;
677 if (sctp_conn->sub_conn[conn_idx].RTO == SCTP_RTO_MIN && sctp_conn->sub_conn[conn_idx].SRTT == 0) // C2: First RTT calculation
679 sctp_conn->sub_conn[conn_idx].SRTT = R;
683 RTTVAR = 100e-3; /* 100 ms */
685 sctp_conn->sub_conn[conn_idx].RTTVAR = RTTVAR;
687 else // C3: RTT already exists; let's recalculate
689 RTTVAR = (1 - SCTP_RTO_BETA) * sctp_conn->sub_conn[conn_idx].RTTVAR +
690 SCTP_RTO_BETA * ABS (sctp_conn->sub_conn[conn_idx].SRTT - R);
693 RTTVAR = 100e-3; /* 100 ms */
695 sctp_conn->sub_conn[conn_idx].RTTVAR = RTTVAR;
697 sctp_conn->sub_conn[conn_idx].SRTT =
698 (1 - SCTP_RTO_ALPHA) * sctp_conn->sub_conn[conn_idx].SRTT +
703 sctp_conn->sub_conn[conn_idx].SRTT +
704 4 * sctp_conn->sub_conn[conn_idx].RTTVAR;
705 if (RTO < SCTP_RTO_MIN) // C6
708 if (RTO > SCTP_RTO_MAX) // C7
711 sctp_conn->sub_conn[conn_idx].RTO = RTO;
715 sctp_timer_update (sctp_connection_t * tc, u8 conn_idx, u8 timer_id,
718 ASSERT (tc->sub_conn[conn_idx].connection.thread_index ==
719 vlib_get_thread_index ());
720 sctp_sub_connection_t *sub = &tc->sub_conn[conn_idx];
722 if (tc->sub_conn[conn_idx].timers[timer_id] != SCTP_TIMER_HANDLE_INVALID)
723 tw_timer_stop_16t_2w_512sl (&sctp_main.timer_wheels[sub->c_thread_index],
724 sub->timers[timer_id]);
726 tc->sub_conn[conn_idx].timers[timer_id] =
727 tw_timer_start_16t_2w_512sl (&sctp_main.timer_wheels[sub->c_thread_index],
728 sub->c_c_index, timer_id, interval);
731 always_inline sctp_connection_t *
732 sctp_listener_get (u32 tli)
734 return pool_elt_at_index (sctp_main.listener_pool, tli);
739 always_inline sctp_connection_t *
740 sctp_connection_get (u32 conn_index, u32 thread_index)
743 (pool_is_free_index (sctp_main.connections[thread_index], conn_index)))
745 return pool_elt_at_index (sctp_main.connections[thread_index], conn_index);
748 #define SELECT_MAX_RETRIES 8
751 sctp_data_subconn_select (sctp_connection_t * sctp_conn)
753 u32 sub = MAIN_SCTP_SUB_CONN_IDX;
754 u8 i, cwnd = sctp_conn->sub_conn[MAIN_SCTP_SUB_CONN_IDX].cwnd;
755 for (i = 1; i < MAX_SCTP_CONNECTIONS; i++)
757 if (sctp_conn->sub_conn[i].state == SCTP_SUBCONN_STATE_DOWN)
760 if (sctp_conn->sub_conn[i].cwnd > cwnd)
763 cwnd = sctp_conn->sub_conn[i].cwnd;
770 sctp_sub_conn_id_via_ip6h (sctp_connection_t * sctp_conn, ip6_header_t * ip6h)
774 for (i = 0; i < MAX_SCTP_CONNECTIONS; i++)
776 if (sctp_conn->sub_conn[i].connection.lcl_ip.ip6.as_u64[0] ==
777 ip6h->dst_address.as_u64[0] &&
778 sctp_conn->sub_conn[i].connection.lcl_ip.ip6.as_u64[1] ==
779 ip6h->dst_address.as_u64[1] &&
780 sctp_conn->sub_conn[i].connection.rmt_ip.ip6.as_u64[0] ==
781 ip6h->src_address.as_u64[0] &&
782 sctp_conn->sub_conn[i].connection.rmt_ip.ip6.as_u64[1] ==
783 ip6h->src_address.as_u64[1])
786 clib_warning ("Did not find a sub-connection; defaulting to %u",
787 MAIN_SCTP_SUB_CONN_IDX);
788 return MAIN_SCTP_SUB_CONN_IDX;
792 sctp_sub_conn_id_via_ip4h (sctp_connection_t * sctp_conn, ip4_header_t * ip4h)
796 for (i = 0; i < MAX_SCTP_CONNECTIONS; i++)
798 if (sctp_conn->sub_conn[i].connection.lcl_ip.ip4.as_u32 ==
799 ip4h->dst_address.as_u32
800 && sctp_conn->sub_conn[i].connection.rmt_ip.ip4.as_u32 ==
801 ip4h->src_address.as_u32)
804 clib_warning ("Did not find a sub-connection; defaulting to %u",
805 MAIN_SCTP_SUB_CONN_IDX);
806 return MAIN_SCTP_SUB_CONN_IDX;
810 * Push SCTP header to buffer
812 * @param vm - vlib_main
813 * @param b - buffer to write the header to
814 * @param sp_net - source port net order
815 * @param dp_net - destination port net order
816 * @param sctp_hdr_opts_len - header and options length in bytes
818 * @return - pointer to start of SCTP header
821 vlib_buffer_push_sctp_net_order (vlib_buffer_t * b, u16 sp, u16 dp,
822 u8 sctp_hdr_opts_len)
824 sctp_full_hdr_t *full_hdr;
826 full_hdr = vlib_buffer_push_uninit (b, sctp_hdr_opts_len);
828 full_hdr->hdr.src_port = sp;
829 full_hdr->hdr.dst_port = dp;
830 full_hdr->hdr.checksum = 0;
835 * Push SCTP header to buffer
837 * @param b - buffer to write the header to
838 * @param sp_net - source port net order
839 * @param dp_net - destination port net order
840 * @param sctp_hdr_opts_len - header and options length in bytes
842 * @return - pointer to start of SCTP header
845 vlib_buffer_push_sctp (vlib_buffer_t * b, u16 sp_net, u16 dp_net,
846 u8 sctp_hdr_opts_len)
848 return vlib_buffer_push_sctp_net_order (b, sp_net, dp_net,
853 sctp_next_avail_subconn (sctp_connection_t * sctp_conn)
857 for (i = 0; i < MAX_SCTP_CONNECTIONS; i++)
859 if (sctp_conn->sub_conn[i].state == SCTP_SUBCONN_STATE_DOWN)
862 return MAX_SCTP_CONNECTIONS;
866 update_smallest_pmtu_idx (sctp_connection_t * sctp_conn)
869 u8 smallest_pmtu_index = MAIN_SCTP_SUB_CONN_IDX;
871 for (i = 1; i < MAX_SCTP_CONNECTIONS; i++)
873 if (sctp_conn->sub_conn[i].state != SCTP_SUBCONN_STATE_DOWN)
875 if (sctp_conn->sub_conn[i].PMTU <
876 sctp_conn->sub_conn[smallest_pmtu_index].PMTU)
877 smallest_pmtu_index = i;
881 sctp_conn->smallest_PMTU_idx = smallest_pmtu_index;
884 /* As per RFC4960; section 7.2.1: Slow-Start */
886 sctp_init_cwnd (sctp_connection_t * sctp_conn)
889 for (i = 0; i < MAX_SCTP_CONNECTIONS; i++)
891 /* Section 7.2.1; point (1) */
892 sctp_conn->sub_conn[i].cwnd =
893 clib_min (4 * sctp_conn->sub_conn[i].PMTU,
894 clib_max (2 * sctp_conn->sub_conn[i].PMTU, 4380));
896 /* Section 7.2.1; point (3) */
897 sctp_conn->sub_conn[i].ssthresh = SCTP_INITIAL_SSHTRESH;
899 /* Section 7.2.2; point (1) */
900 sctp_conn->sub_conn[i].partially_acked_bytes = 0;
905 sctp_in_cong_recovery (sctp_connection_t * sctp_conn, u8 idx)
911 cwnd_fully_utilized (sctp_connection_t * sctp_conn, u8 idx)
916 /* As per RFC4960; section 7.2.1: Slow-Start */
918 update_cwnd (sctp_connection_t * sctp_conn)
922 for (i = 0; i < MAX_SCTP_CONNECTIONS; i++)
924 /* Section 7.2.1; point (2) */
925 if (sctp_conn->sub_conn[i].is_retransmitting)
927 sctp_conn->sub_conn[i].cwnd = 1 * sctp_conn->sub_conn[i].PMTU;
931 /* Section 7.2.2; point (4) */
932 if (sctp_conn->sub_conn[i].last_data_ts >
933 sctp_time_now () + SCTP_DATA_IDLE_INTERVAL)
935 sctp_conn->sub_conn[i].cwnd =
936 clib_max (sctp_conn->sub_conn[i].cwnd / 2,
937 4 * sctp_conn->sub_conn[i].PMTU);
941 /* Section 7.2.1; point (5) */
942 if (sctp_conn->sub_conn[i].cwnd <= sctp_conn->sub_conn[i].ssthresh)
944 if (!cwnd_fully_utilized (sctp_conn, i))
947 if (sctp_in_cong_recovery (sctp_conn, i))
950 sctp_conn->sub_conn[i].cwnd =
951 clib_min (sctp_conn->sub_conn[i].PMTU, 1);
957 * fd.io coding-style-patch-verification: ON
960 * eval: (c-set-style "gnu")