lsquic_engine.c revision 355db7c6
1/* Copyright (c) 2017 - 2018 LiteSpeed Technologies Inc. See LICENSE. */ 2/* 3 * lsquic_engine.c - QUIC engine 4 */ 5 6#include <assert.h> 7#include <errno.h> 8#include <inttypes.h> 9#include <stdint.h> 10#include <stdio.h> 11#include <stdlib.h> 12#include <string.h> 13#include <sys/queue.h> 14#include <time.h> 15#ifndef WIN32 16#include <sys/time.h> 17#include <netinet/in.h> 18#include <sys/types.h> 19#include <sys/stat.h> 20#include <fcntl.h> 21#include <unistd.h> 22#include <netdb.h> 23#endif 24 25 26 27#include "lsquic.h" 28#include "lsquic_types.h" 29#include "lsquic_alarmset.h" 30#include "lsquic_parse.h" 31#include "lsquic_packet_in.h" 32#include "lsquic_packet_out.h" 33#include "lsquic_senhist.h" 34#include "lsquic_rtt.h" 35#include "lsquic_cubic.h" 36#include "lsquic_pacer.h" 37#include "lsquic_send_ctl.h" 38#include "lsquic_set.h" 39#include "lsquic_conn_flow.h" 40#include "lsquic_sfcw.h" 41#include "lsquic_stream.h" 42#include "lsquic_conn.h" 43#include "lsquic_full_conn.h" 44#include "lsquic_util.h" 45#include "lsquic_qtags.h" 46#include "lsquic_str.h" 47#include "lsquic_handshake.h" 48#include "lsquic_mm.h" 49#include "lsquic_conn_hash.h" 50#include "lsquic_engine_public.h" 51#include "lsquic_eng_hist.h" 52#include "lsquic_ev_log.h" 53#include "lsquic_version.h" 54#include "lsquic_hash.h" 55#include "lsquic_attq.h" 56#include "lsquic_min_heap.h" 57 58#define LSQUIC_LOGGER_MODULE LSQLM_ENGINE 59#include "lsquic_logger.h" 60 61 62/* The batch of outgoing packets grows and shrinks dynamically */ 63#define MAX_OUT_BATCH_SIZE 1024 64#define MIN_OUT_BATCH_SIZE 256 65#define INITIAL_OUT_BATCH_SIZE 512 66 67struct out_batch 68{ 69 lsquic_conn_t *conns [MAX_OUT_BATCH_SIZE]; 70 lsquic_packet_out_t *packets[MAX_OUT_BATCH_SIZE]; 71 struct lsquic_out_spec outs [MAX_OUT_BATCH_SIZE]; 72}; 73 74typedef struct lsquic_conn * (*conn_iter_f)(struct lsquic_engine *); 75 76static void 77process_connections (struct lsquic_engine *engine, conn_iter_f iter, 78 lsquic_time_t now); 79 80static void 81engine_incref_conn (lsquic_conn_t *conn, enum lsquic_conn_flags flag); 82 83static lsquic_conn_t * 84engine_decref_conn (lsquic_engine_t *engine, lsquic_conn_t *conn, 85 enum lsquic_conn_flags flag); 86 87static void 88force_close_conn (lsquic_engine_t *engine, lsquic_conn_t *conn); 89 90/* Nested calls to LSQUIC are not supported */ 91#define ENGINE_IN(e) do { \ 92 assert(!((e)->pub.enp_flags & ENPUB_PROC)); \ 93 (e)->pub.enp_flags |= ENPUB_PROC; \ 94} while (0) 95 96#define ENGINE_OUT(e) do { \ 97 assert((e)->pub.enp_flags & ENPUB_PROC); \ 98 (e)->pub.enp_flags &= ~ENPUB_PROC; \ 99} while (0) 100 101/* A connection can be referenced from one of five places: 102 * 103 * 1. Connection hash: a connection starts its life in one of those. 104 * 105 * 2. Outgoing queue. 106 * 107 * 3. Tickable queue 108 * 109 * 4. Advisory Tick Time queue. 110 * 111 * 5. Closing connections queue. This is a transient queue -- it only 112 * exists for the duration of process_connections() function call. 113 * 114 * The idea is to destroy the connection when it is no longer referenced. 115 * For example, a connection tick may return TICK_SEND|TICK_CLOSE. In 116 * that case, the connection is referenced from two places: (2) and (5). 117 * After its packets are sent, it is only referenced in (5), and at the 118 * end of the function call, when it is removed from (5), reference count 119 * goes to zero and the connection is destroyed. If not all packets can 120 * be sent, at the end of the function call, the connection is referenced 121 * by (2) and will only be removed once all outgoing packets have been 122 * sent. 123 */ 124#define CONN_REF_FLAGS (LSCONN_HASHED \ 125 |LSCONN_HAS_OUTGOING \ 126 |LSCONN_TICKABLE \ 127 |LSCONN_CLOSING \ 128 |LSCONN_ATTQ) 129 130 131 132 133struct lsquic_engine 134{ 135 struct lsquic_engine_public pub; 136 enum { 137 ENG_SERVER = LSENG_SERVER, 138 ENG_HTTP = LSENG_HTTP, 139 ENG_COOLDOWN = (1 << 7), /* Cooldown: no new connections */ 140 ENG_PAST_DEADLINE 141 = (1 << 8), /* Previous call to a processing 142 * function went past time threshold. 143 */ 144#ifndef NDEBUG 145 ENG_DTOR = (1 << 26), /* Engine destructor */ 146#endif 147 } flags; 148 const struct lsquic_stream_if *stream_if; 149 void *stream_if_ctx; 150 lsquic_packets_out_f packets_out; 151 void *packets_out_ctx; 152 void *bad_handshake_ctx; 153 struct conn_hash conns_hash; 154 struct min_heap conns_tickable; 155 struct min_heap conns_out; 156 struct eng_hist history; 157 unsigned batch_size; 158 struct attq *attq; 159 /* Track time last time a packet was sent to give new connections 160 * priority lower than that of existing connections. 161 */ 162 lsquic_time_t last_sent; 163 unsigned n_conns; 164 lsquic_time_t deadline; 165 struct out_batch out_batch; 166}; 167 168 169void 170lsquic_engine_init_settings (struct lsquic_engine_settings *settings, 171 unsigned flags) 172{ 173 memset(settings, 0, sizeof(*settings)); 174 settings->es_versions = LSQUIC_DF_VERSIONS; 175 if (flags & ENG_SERVER) 176 { 177 settings->es_cfcw = LSQUIC_DF_CFCW_SERVER; 178 settings->es_sfcw = LSQUIC_DF_SFCW_SERVER; 179 settings->es_support_srej= LSQUIC_DF_SUPPORT_SREJ_SERVER; 180 } 181 else 182 { 183 settings->es_cfcw = LSQUIC_DF_CFCW_CLIENT; 184 settings->es_sfcw = LSQUIC_DF_SFCW_CLIENT; 185 settings->es_support_srej= LSQUIC_DF_SUPPORT_SREJ_CLIENT; 186 } 187 settings->es_max_streams_in = LSQUIC_DF_MAX_STREAMS_IN; 188 settings->es_idle_conn_to = LSQUIC_DF_IDLE_CONN_TO; 189 settings->es_handshake_to = LSQUIC_DF_HANDSHAKE_TO; 190 settings->es_silent_close = LSQUIC_DF_SILENT_CLOSE; 191 settings->es_max_header_list_size 192 = LSQUIC_DF_MAX_HEADER_LIST_SIZE; 193 settings->es_ua = LSQUIC_DF_UA; 194 195 settings->es_pdmd = QTAG_X509; 196 settings->es_aead = QTAG_AESG; 197 settings->es_kexs = QTAG_C255; 198 settings->es_support_push = LSQUIC_DF_SUPPORT_PUSH; 199 settings->es_support_tcid0 = LSQUIC_DF_SUPPORT_TCID0; 200 settings->es_support_nstp = LSQUIC_DF_SUPPORT_NSTP; 201 settings->es_honor_prst = LSQUIC_DF_HONOR_PRST; 202 settings->es_progress_check = LSQUIC_DF_PROGRESS_CHECK; 203 settings->es_rw_once = LSQUIC_DF_RW_ONCE; 204 settings->es_proc_time_thresh= LSQUIC_DF_PROC_TIME_THRESH; 205 settings->es_pace_packets = LSQUIC_DF_PACE_PACKETS; 206} 207 208 209/* Note: if returning an error, err_buf must be valid if non-NULL */ 210int 211lsquic_engine_check_settings (const struct lsquic_engine_settings *settings, 212 unsigned flags, 213 char *err_buf, size_t err_buf_sz) 214{ 215 if (settings->es_cfcw < LSQUIC_MIN_FCW || 216 settings->es_sfcw < LSQUIC_MIN_FCW) 217 { 218 if (err_buf) 219 snprintf(err_buf, err_buf_sz, "%s", 220 "flow control window set too low"); 221 return -1; 222 } 223 if (0 == (settings->es_versions & LSQUIC_SUPPORTED_VERSIONS)) 224 { 225 if (err_buf) 226 snprintf(err_buf, err_buf_sz, "%s", 227 "No supported QUIC versions specified"); 228 return -1; 229 } 230 if (settings->es_versions & ~LSQUIC_SUPPORTED_VERSIONS) 231 { 232 if (err_buf) 233 snprintf(err_buf, err_buf_sz, "%s", 234 "one or more unsupported QUIC version is specified"); 235 return -1; 236 } 237 return 0; 238} 239 240 241static void 242free_packet (void *ctx, unsigned char *packet_data) 243{ 244 free(packet_data); 245} 246 247 248static void * 249malloc_buf (void *ctx, size_t size) 250{ 251 return malloc(size); 252} 253 254 255static const struct lsquic_packout_mem_if stock_pmi = 256{ 257 malloc_buf, (void(*)(void *, void *)) free_packet, 258}; 259 260 261lsquic_engine_t * 262lsquic_engine_new (unsigned flags, 263 const struct lsquic_engine_api *api) 264{ 265 lsquic_engine_t *engine; 266 int tag_buf_len; 267 char err_buf[100]; 268 269 if (!api->ea_packets_out) 270 { 271 LSQ_ERROR("packets_out callback is not specified"); 272 return NULL; 273 } 274 275 if (api->ea_settings && 276 0 != lsquic_engine_check_settings(api->ea_settings, flags, 277 err_buf, sizeof(err_buf))) 278 { 279 LSQ_ERROR("cannot create engine: %s", err_buf); 280 return NULL; 281 } 282 283 engine = calloc(1, sizeof(*engine)); 284 if (!engine) 285 return NULL; 286 if (0 != lsquic_mm_init(&engine->pub.enp_mm)) 287 { 288 free(engine); 289 return NULL; 290 } 291 if (api->ea_settings) 292 engine->pub.enp_settings = *api->ea_settings; 293 else 294 lsquic_engine_init_settings(&engine->pub.enp_settings, flags); 295 tag_buf_len = gen_ver_tags(engine->pub.enp_ver_tags_buf, 296 sizeof(engine->pub.enp_ver_tags_buf), 297 engine->pub.enp_settings.es_versions); 298 if (tag_buf_len <= 0) 299 { 300 LSQ_ERROR("cannot generate version tags buffer"); 301 free(engine); 302 return NULL; 303 } 304 engine->pub.enp_ver_tags_len = tag_buf_len; 305 306 engine->flags = flags; 307 engine->stream_if = api->ea_stream_if; 308 engine->stream_if_ctx = api->ea_stream_if_ctx; 309 engine->packets_out = api->ea_packets_out; 310 engine->packets_out_ctx = api->ea_packets_out_ctx; 311 if (api->ea_pmi) 312 { 313 engine->pub.enp_pmi = api->ea_pmi; 314 engine->pub.enp_pmi_ctx = api->ea_pmi_ctx; 315 } 316 else 317 { 318 engine->pub.enp_pmi = &stock_pmi; 319 engine->pub.enp_pmi_ctx = NULL; 320 } 321 engine->pub.enp_engine = engine; 322 conn_hash_init(&engine->conns_hash); 323 engine->attq = attq_create(); 324 eng_hist_init(&engine->history); 325 engine->batch_size = INITIAL_OUT_BATCH_SIZE; 326 327 328 LSQ_INFO("instantiated engine"); 329 return engine; 330} 331 332 333static void 334grow_batch_size (struct lsquic_engine *engine) 335{ 336 engine->batch_size <<= engine->batch_size < MAX_OUT_BATCH_SIZE; 337} 338 339 340static void 341shrink_batch_size (struct lsquic_engine *engine) 342{ 343 engine->batch_size >>= engine->batch_size > MIN_OUT_BATCH_SIZE; 344} 345 346 347/* Wrapper to make sure important things occur before the connection is 348 * really destroyed. 349 */ 350static void 351destroy_conn (struct lsquic_engine *engine, lsquic_conn_t *conn) 352{ 353 --engine->n_conns; 354 conn->cn_flags |= LSCONN_NEVER_TICKABLE; 355 conn->cn_if->ci_destroy(conn); 356} 357 358 359static int 360maybe_grow_conn_heaps (struct lsquic_engine *engine) 361{ 362 struct min_heap_elem *els; 363 unsigned count; 364 365 if (engine->n_conns < lsquic_mh_nalloc(&engine->conns_tickable)) 366 return 0; /* Nothing to do */ 367 368 if (lsquic_mh_nalloc(&engine->conns_tickable)) 369 count = lsquic_mh_nalloc(&engine->conns_tickable) * 2 * 2; 370 else 371 count = 8; 372 373 els = malloc(sizeof(els[0]) * count); 374 if (!els) 375 { 376 LSQ_ERROR("%s: malloc failed", __func__); 377 return -1; 378 } 379 380 LSQ_DEBUG("grew heaps to %u elements", count / 2); 381 memcpy(&els[0], engine->conns_tickable.mh_elems, 382 sizeof(els[0]) * lsquic_mh_count(&engine->conns_tickable)); 383 memcpy(&els[count / 2], engine->conns_out.mh_elems, 384 sizeof(els[0]) * lsquic_mh_count(&engine->conns_out)); 385 free(engine->conns_tickable.mh_elems); 386 engine->conns_tickable.mh_elems = els; 387 engine->conns_out.mh_elems = &els[count / 2]; 388 engine->conns_tickable.mh_nalloc = count / 2; 389 engine->conns_out.mh_nalloc = count / 2; 390 return 0; 391} 392 393 394static lsquic_conn_t * 395new_full_conn_client (lsquic_engine_t *engine, const char *hostname, 396 unsigned short max_packet_size) 397{ 398 lsquic_conn_t *conn; 399 unsigned flags; 400 if (0 != maybe_grow_conn_heaps(engine)) 401 return NULL; 402 flags = engine->flags & (ENG_SERVER|ENG_HTTP); 403 conn = full_conn_client_new(&engine->pub, engine->stream_if, 404 engine->stream_if_ctx, flags, hostname, max_packet_size); 405 if (!conn) 406 return NULL; 407 ++engine->n_conns; 408 if (0 != conn_hash_add(&engine->conns_hash, conn)) 409 { 410 LSQ_WARN("cannot add connection %"PRIu64" to hash - destroy", 411 conn->cn_cid); 412 destroy_conn(engine, conn); 413 return NULL; 414 } 415 assert(!(conn->cn_flags & 416 (CONN_REF_FLAGS 417 & ~LSCONN_TICKABLE /* This flag may be set as effect of user 418 callbacks */ 419 ))); 420 conn->cn_flags |= LSCONN_HASHED; 421 return conn; 422} 423 424 425static lsquic_conn_t * 426find_or_create_conn (lsquic_engine_t *engine, lsquic_packet_in_t *packet_in, 427 struct packin_parse_state *ppstate, const struct sockaddr *sa_peer, 428 void *peer_ctx) 429{ 430 lsquic_conn_t *conn; 431 432 if (lsquic_packet_in_is_prst(packet_in) 433 && !engine->pub.enp_settings.es_honor_prst) 434 { 435 LSQ_DEBUG("public reset packet: discarding"); 436 return NULL; 437 } 438 439 if (!(packet_in->pi_flags & PI_CONN_ID)) 440 { 441 LSQ_DEBUG("packet header does not have connection ID: discarding"); 442 return NULL; 443 } 444 445 conn = conn_hash_find(&engine->conns_hash, packet_in->pi_conn_id); 446 if (conn) 447 { 448 conn->cn_pf->pf_parse_packet_in_finish(packet_in, ppstate); 449 return conn; 450 } 451 452 return conn; 453} 454 455 456#if !defined(NDEBUG) && __GNUC__ 457__attribute__((weak)) 458#endif 459void 460lsquic_engine_add_conn_to_tickable (struct lsquic_engine_public *enpub, 461 lsquic_conn_t *conn) 462{ 463 if (0 == (enpub->enp_flags & ENPUB_PROC) && 464 0 == (conn->cn_flags & (LSCONN_TICKABLE|LSCONN_NEVER_TICKABLE))) 465 { 466 lsquic_engine_t *engine = (lsquic_engine_t *) enpub; 467 lsquic_mh_insert(&engine->conns_tickable, conn, conn->cn_last_ticked); 468 engine_incref_conn(conn, LSCONN_TICKABLE); 469 } 470} 471 472 473void 474lsquic_engine_add_conn_to_attq (struct lsquic_engine_public *enpub, 475 lsquic_conn_t *conn, lsquic_time_t tick_time) 476{ 477 lsquic_engine_t *const engine = (lsquic_engine_t *) enpub; 478 if (conn->cn_flags & LSCONN_TICKABLE) 479 { 480 /* Optimization: no need to add the connection to the Advisory Tick 481 * Time Queue: it is about to be ticked, after which it its next tick 482 * time may be queried again. 483 */; 484 } 485 else if (conn->cn_flags & LSCONN_ATTQ) 486 { 487 if (lsquic_conn_adv_time(conn) != tick_time) 488 { 489 attq_remove(engine->attq, conn); 490 if (0 != attq_add(engine->attq, conn, tick_time)) 491 engine_decref_conn(engine, conn, LSCONN_ATTQ); 492 } 493 } 494 else if (0 == attq_add(engine->attq, conn, tick_time)) 495 engine_incref_conn(conn, LSCONN_ATTQ); 496} 497 498 499/* Return 0 if packet is being processed by a connections, otherwise return 1 */ 500static int 501process_packet_in (lsquic_engine_t *engine, lsquic_packet_in_t *packet_in, 502 struct packin_parse_state *ppstate, const struct sockaddr *sa_local, 503 const struct sockaddr *sa_peer, void *peer_ctx) 504{ 505 lsquic_conn_t *conn; 506 507 conn = find_or_create_conn(engine, packet_in, ppstate, sa_peer, peer_ctx); 508 if (!conn) 509 { 510 lsquic_mm_put_packet_in(&engine->pub.enp_mm, packet_in); 511 return 1; 512 } 513 514 if (0 == (conn->cn_flags & LSCONN_TICKABLE)) 515 { 516 lsquic_mh_insert(&engine->conns_tickable, conn, conn->cn_last_ticked); 517 engine_incref_conn(conn, LSCONN_TICKABLE); 518 } 519 lsquic_conn_record_sockaddr(conn, sa_local, sa_peer); 520 lsquic_packet_in_upref(packet_in); 521 conn->cn_peer_ctx = peer_ctx; 522 conn->cn_if->ci_packet_in(conn, packet_in); 523 lsquic_packet_in_put(&engine->pub.enp_mm, packet_in); 524 return 0; 525} 526 527 528void 529lsquic_engine_destroy (lsquic_engine_t *engine) 530{ 531 lsquic_conn_t *conn; 532 533 LSQ_DEBUG("destroying engine"); 534#ifndef NDEBUG 535 engine->flags |= ENG_DTOR; 536#endif 537 538 while ((conn = lsquic_mh_pop(&engine->conns_out))) 539 { 540 assert(conn->cn_flags & LSCONN_HAS_OUTGOING); 541 (void) engine_decref_conn(engine, conn, LSCONN_HAS_OUTGOING); 542 } 543 544 while ((conn = lsquic_mh_pop(&engine->conns_tickable))) 545 { 546 assert(conn->cn_flags & LSCONN_TICKABLE); 547 (void) engine_decref_conn(engine, conn, LSCONN_TICKABLE); 548 } 549 550 for (conn = conn_hash_first(&engine->conns_hash); conn; 551 conn = conn_hash_next(&engine->conns_hash)) 552 force_close_conn(engine, conn); 553 conn_hash_cleanup(&engine->conns_hash); 554 555 assert(0 == engine->n_conns); 556 attq_destroy(engine->attq); 557 558 assert(0 == lsquic_mh_count(&engine->conns_out)); 559 assert(0 == lsquic_mh_count(&engine->conns_tickable)); 560 free(engine->conns_tickable.mh_elems); 561 free(engine); 562} 563 564 565lsquic_conn_t * 566lsquic_engine_connect (lsquic_engine_t *engine, const struct sockaddr *peer_sa, 567 void *peer_ctx, lsquic_conn_ctx_t *conn_ctx, 568 const char *hostname, unsigned short max_packet_size) 569{ 570 lsquic_conn_t *conn; 571 ENGINE_IN(engine); 572 573 if (engine->flags & ENG_SERVER) 574 { 575 LSQ_ERROR("`%s' must only be called in client mode", __func__); 576 goto err; 577 } 578 579 if (0 == max_packet_size) 580 { 581 switch (peer_sa->sa_family) 582 { 583 case AF_INET: 584 max_packet_size = QUIC_MAX_IPv4_PACKET_SZ; 585 break; 586 default: 587 max_packet_size = QUIC_MAX_IPv6_PACKET_SZ; 588 break; 589 } 590 } 591 592 conn = new_full_conn_client(engine, hostname, max_packet_size); 593 if (!conn) 594 goto err; 595 lsquic_mh_insert(&engine->conns_tickable, conn, conn->cn_last_ticked); 596 engine_incref_conn(conn, LSCONN_TICKABLE); 597 lsquic_conn_record_peer_sa(conn, peer_sa); 598 conn->cn_peer_ctx = peer_ctx; 599 lsquic_conn_set_ctx(conn, conn_ctx); 600 full_conn_client_call_on_new(conn); 601 end: 602 ENGINE_OUT(engine); 603 return conn; 604 err: 605 conn = NULL; 606 goto end; 607} 608 609 610static void 611remove_conn_from_hash (lsquic_engine_t *engine, lsquic_conn_t *conn) 612{ 613 conn_hash_remove(&engine->conns_hash, conn); 614 (void) engine_decref_conn(engine, conn, LSCONN_HASHED); 615} 616 617 618static void 619refflags2str (enum lsquic_conn_flags flags, char s[6]) 620{ 621 *s = 'C'; s += !!(flags & LSCONN_CLOSING); 622 *s = 'H'; s += !!(flags & LSCONN_HASHED); 623 *s = 'O'; s += !!(flags & LSCONN_HAS_OUTGOING); 624 *s = 'T'; s += !!(flags & LSCONN_TICKABLE); 625 *s = 'A'; s += !!(flags & LSCONN_ATTQ); 626 *s = '\0'; 627} 628 629 630static void 631engine_incref_conn (lsquic_conn_t *conn, enum lsquic_conn_flags flag) 632{ 633 char str[2][6]; 634 assert(flag & CONN_REF_FLAGS); 635 assert(!(conn->cn_flags & flag)); 636 conn->cn_flags |= flag; 637 LSQ_DEBUG("incref conn %"PRIu64", '%s' -> '%s'", conn->cn_cid, 638 (refflags2str(conn->cn_flags & ~flag, str[0]), str[0]), 639 (refflags2str(conn->cn_flags, str[1]), str[1])); 640} 641 642 643static lsquic_conn_t * 644engine_decref_conn (lsquic_engine_t *engine, lsquic_conn_t *conn, 645 enum lsquic_conn_flags flags) 646{ 647 char str[2][6]; 648 assert(flags & CONN_REF_FLAGS); 649 assert(conn->cn_flags & flags); 650#ifndef NDEBUG 651 if (flags & LSCONN_CLOSING) 652 assert(0 == (conn->cn_flags & LSCONN_HASHED)); 653#endif 654 conn->cn_flags &= ~flags; 655 LSQ_DEBUG("decref conn %"PRIu64", '%s' -> '%s'", conn->cn_cid, 656 (refflags2str(conn->cn_flags | flags, str[0]), str[0]), 657 (refflags2str(conn->cn_flags, str[1]), str[1])); 658 if (0 == (conn->cn_flags & CONN_REF_FLAGS)) 659 { 660 eng_hist_inc(&engine->history, 0, sl_del_full_conns); 661 destroy_conn(engine, conn); 662 return NULL; 663 } 664 else 665 return conn; 666} 667 668 669/* This is not a general-purpose function. Only call from engine dtor. */ 670static void 671force_close_conn (lsquic_engine_t *engine, lsquic_conn_t *conn) 672{ 673 assert(engine->flags & ENG_DTOR); 674 const enum lsquic_conn_flags flags = conn->cn_flags; 675 assert(conn->cn_flags & CONN_REF_FLAGS); 676 assert(!(flags & LSCONN_HAS_OUTGOING)); /* Should be removed already */ 677 assert(!(flags & LSCONN_TICKABLE)); /* Should be removed already */ 678 assert(!(flags & LSCONN_CLOSING)); /* It is in transient queue? */ 679 if (flags & LSCONN_ATTQ) 680 { 681 attq_remove(engine->attq, conn); 682 (void) engine_decref_conn(engine, conn, LSCONN_ATTQ); 683 } 684 if (flags & LSCONN_HASHED) 685 remove_conn_from_hash(engine, conn); 686} 687 688 689/* Iterator for tickable connections (those on the Tickable Queue). Before 690 * a connection is returned, it is removed from the Advisory Tick Time queue 691 * if necessary. 692 */ 693static lsquic_conn_t * 694conn_iter_next_tickable (struct lsquic_engine *engine) 695{ 696 lsquic_conn_t *conn; 697 698 conn = lsquic_mh_pop(&engine->conns_tickable); 699 700 if (conn) 701 conn = engine_decref_conn(engine, conn, LSCONN_TICKABLE); 702 if (conn && (conn->cn_flags & LSCONN_ATTQ)) 703 { 704 attq_remove(engine->attq, conn); 705 conn = engine_decref_conn(engine, conn, LSCONN_ATTQ); 706 } 707 708 return conn; 709} 710 711 712void 713lsquic_engine_process_conns (lsquic_engine_t *engine) 714{ 715 lsquic_conn_t *conn; 716 lsquic_time_t now; 717 718 ENGINE_IN(engine); 719 720 now = lsquic_time_now(); 721 while ((conn = attq_pop(engine->attq, now))) 722 { 723 conn = engine_decref_conn(engine, conn, LSCONN_ATTQ); 724 if (conn && !(conn->cn_flags & LSCONN_TICKABLE)) 725 { 726 lsquic_mh_insert(&engine->conns_tickable, conn, conn->cn_last_ticked); 727 engine_incref_conn(conn, LSCONN_TICKABLE); 728 } 729 } 730 731 process_connections(engine, conn_iter_next_tickable, now); 732 ENGINE_OUT(engine); 733} 734 735 736static int 737generate_header (const lsquic_packet_out_t *packet_out, 738 const struct parse_funcs *pf, lsquic_cid_t cid, 739 unsigned char *buf, size_t bufsz) 740{ 741 return pf->pf_gen_reg_pkt_header(buf, bufsz, 742 packet_out->po_flags & PO_CONN_ID ? &cid : NULL, 743 packet_out->po_flags & PO_VERSION ? &packet_out->po_ver_tag : NULL, 744 packet_out->po_flags & PO_NONCE ? packet_out->po_nonce : NULL, 745 packet_out->po_packno, lsquic_packet_out_packno_bits(packet_out)); 746} 747 748 749static ssize_t 750really_encrypt_packet (const lsquic_conn_t *conn, 751 const lsquic_packet_out_t *packet_out, 752 unsigned char *buf, size_t bufsz) 753{ 754 int enc, header_sz, is_hello_packet; 755 size_t packet_sz; 756 unsigned char header_buf[QUIC_MAX_PUBHDR_SZ]; 757 758 header_sz = generate_header(packet_out, conn->cn_pf, conn->cn_cid, 759 header_buf, sizeof(header_buf)); 760 if (header_sz < 0) 761 return -1; 762 763 is_hello_packet = !!(packet_out->po_flags & PO_HELLO); 764 enc = conn->cn_esf->esf_encrypt(conn->cn_enc_session, conn->cn_version, 0, 765 packet_out->po_packno, header_buf, header_sz, 766 packet_out->po_data, packet_out->po_data_sz, 767 buf, bufsz, &packet_sz, is_hello_packet); 768 if (0 == enc) 769 { 770 LSQ_DEBUG("encrypted packet %"PRIu64"; plaintext is %u bytes, " 771 "ciphertext is %zd bytes", 772 packet_out->po_packno, 773 lsquic_po_header_length(packet_out->po_flags) + 774 packet_out->po_data_sz, 775 packet_sz); 776 return packet_sz; 777 } 778 else 779 return -1; 780} 781 782 783static enum { ENCPA_OK, ENCPA_NOMEM, ENCPA_BADCRYPT, } 784encrypt_packet (lsquic_engine_t *engine, const lsquic_conn_t *conn, 785 lsquic_packet_out_t *packet_out) 786{ 787 ssize_t enc_sz; 788 size_t bufsz; 789 unsigned sent_sz; 790 unsigned char *buf; 791 792 bufsz = lsquic_po_header_length(packet_out->po_flags) + 793 packet_out->po_data_sz + QUIC_PACKET_HASH_SZ; 794 buf = engine->pub.enp_pmi->pmi_allocate(engine->pub.enp_pmi_ctx, bufsz); 795 if (!buf) 796 { 797 LSQ_DEBUG("could not allocate memory for outgoing packet of size %zd", 798 bufsz); 799 return ENCPA_NOMEM; 800 } 801 802 { 803 enc_sz = really_encrypt_packet(conn, packet_out, buf, bufsz); 804 sent_sz = enc_sz; 805 } 806 807 if (enc_sz < 0) 808 { 809 engine->pub.enp_pmi->pmi_release(engine->pub.enp_pmi_ctx, buf); 810 return ENCPA_BADCRYPT; 811 } 812 813 packet_out->po_enc_data = buf; 814 packet_out->po_enc_data_sz = enc_sz; 815 packet_out->po_sent_sz = sent_sz; 816 packet_out->po_flags |= PO_ENCRYPTED|PO_SENT_SZ; 817 818 return ENCPA_OK; 819} 820 821 822STAILQ_HEAD(conns_stailq, lsquic_conn); 823 824 825struct conns_out_iter 826{ 827 struct min_heap *coi_heap; 828 TAILQ_HEAD(, lsquic_conn) coi_active_list, 829 coi_inactive_list; 830 lsquic_conn_t *coi_next; 831#ifndef NDEBUG 832 lsquic_time_t coi_last_sent; 833#endif 834}; 835 836 837static void 838coi_init (struct conns_out_iter *iter, struct lsquic_engine *engine) 839{ 840 iter->coi_heap = &engine->conns_out; 841 iter->coi_next = NULL; 842 TAILQ_INIT(&iter->coi_active_list); 843 TAILQ_INIT(&iter->coi_inactive_list); 844#ifndef NDEBUG 845 iter->coi_last_sent = 0; 846#endif 847} 848 849 850static lsquic_conn_t * 851coi_next (struct conns_out_iter *iter) 852{ 853 lsquic_conn_t *conn; 854 855 if (lsquic_mh_count(iter->coi_heap) > 0) 856 { 857 conn = lsquic_mh_pop(iter->coi_heap); 858 TAILQ_INSERT_TAIL(&iter->coi_active_list, conn, cn_next_out); 859 conn->cn_flags |= LSCONN_COI_ACTIVE; 860#ifndef NDEBUG 861 if (iter->coi_last_sent) 862 assert(iter->coi_last_sent <= conn->cn_last_sent); 863 iter->coi_last_sent = conn->cn_last_sent; 864#endif 865 return conn; 866 } 867 else if (!TAILQ_EMPTY(&iter->coi_active_list)) 868 { 869 conn = iter->coi_next; 870 if (!conn) 871 conn = TAILQ_FIRST(&iter->coi_active_list); 872 if (conn) 873 iter->coi_next = TAILQ_NEXT(conn, cn_next_out); 874 return conn; 875 } 876 else 877 return NULL; 878} 879 880 881static void 882coi_deactivate (struct conns_out_iter *iter, lsquic_conn_t *conn) 883{ 884 if (!(conn->cn_flags & LSCONN_EVANESCENT)) 885 { 886 assert(!TAILQ_EMPTY(&iter->coi_active_list)); 887 TAILQ_REMOVE(&iter->coi_active_list, conn, cn_next_out); 888 conn->cn_flags &= ~LSCONN_COI_ACTIVE; 889 TAILQ_INSERT_TAIL(&iter->coi_inactive_list, conn, cn_next_out); 890 conn->cn_flags |= LSCONN_COI_INACTIVE; 891 } 892} 893 894 895static void 896coi_remove (struct conns_out_iter *iter, lsquic_conn_t *conn) 897{ 898 assert(conn->cn_flags & LSCONN_COI_ACTIVE); 899 if (conn->cn_flags & LSCONN_COI_ACTIVE) 900 { 901 TAILQ_REMOVE(&iter->coi_active_list, conn, cn_next_out); 902 conn->cn_flags &= ~LSCONN_COI_ACTIVE; 903 } 904} 905 906 907static void 908coi_reactivate (struct conns_out_iter *iter, lsquic_conn_t *conn) 909{ 910 assert(conn->cn_flags & LSCONN_COI_INACTIVE); 911 TAILQ_REMOVE(&iter->coi_inactive_list, conn, cn_next_out); 912 conn->cn_flags &= ~LSCONN_COI_INACTIVE; 913 TAILQ_INSERT_TAIL(&iter->coi_active_list, conn, cn_next_out); 914 conn->cn_flags |= LSCONN_COI_ACTIVE; 915} 916 917 918static void 919coi_reheap (struct conns_out_iter *iter, lsquic_engine_t *engine) 920{ 921 lsquic_conn_t *conn; 922 while ((conn = TAILQ_FIRST(&iter->coi_active_list))) 923 { 924 TAILQ_REMOVE(&iter->coi_active_list, conn, cn_next_out); 925 conn->cn_flags &= ~LSCONN_COI_ACTIVE; 926 lsquic_mh_insert(iter->coi_heap, conn, conn->cn_last_sent); 927 } 928 while ((conn = TAILQ_FIRST(&iter->coi_inactive_list))) 929 { 930 TAILQ_REMOVE(&iter->coi_inactive_list, conn, cn_next_out); 931 conn->cn_flags &= ~LSCONN_COI_INACTIVE; 932 (void) engine_decref_conn(engine, conn, LSCONN_HAS_OUTGOING); 933 } 934} 935 936 937static unsigned 938send_batch (lsquic_engine_t *engine, struct conns_out_iter *conns_iter, 939 struct out_batch *batch, unsigned n_to_send) 940{ 941 int n_sent, i; 942 lsquic_time_t now; 943 944 /* Set sent time before the write to avoid underestimating RTT */ 945 now = lsquic_time_now(); 946 for (i = 0; i < (int) n_to_send; ++i) 947 batch->packets[i]->po_sent = now; 948 n_sent = engine->packets_out(engine->packets_out_ctx, batch->outs, 949 n_to_send); 950 if (n_sent >= 0) 951 LSQ_DEBUG("packets out returned %d (out of %u)", n_sent, n_to_send); 952 else 953 { 954 LSQ_DEBUG("packets out returned an error: %s", strerror(errno)); 955 n_sent = 0; 956 } 957 if (n_sent > 0) 958 engine->last_sent = now + n_sent; 959 for (i = 0; i < n_sent; ++i) 960 { 961 eng_hist_inc(&engine->history, now, sl_packets_out); 962 EV_LOG_PACKET_SENT(batch->conns[i]->cn_cid, batch->packets[i]); 963 batch->conns[i]->cn_if->ci_packet_sent(batch->conns[i], 964 batch->packets[i]); 965 /* `i' is added to maintain relative order */ 966 batch->conns[i]->cn_last_sent = now + i; 967 /* Release packet out buffer as soon as the packet is sent 968 * successfully. If not successfully sent, we hold on to 969 * this buffer until the packet sending is attempted again 970 * or until it times out and regenerated. 971 */ 972 if (batch->packets[i]->po_flags & PO_ENCRYPTED) 973 { 974 batch->packets[i]->po_flags &= ~PO_ENCRYPTED; 975 engine->pub.enp_pmi->pmi_release(engine->pub.enp_pmi_ctx, 976 batch->packets[i]->po_enc_data); 977 batch->packets[i]->po_enc_data = NULL; /* JIC */ 978 } 979 } 980 if (LSQ_LOG_ENABLED_EXT(LSQ_LOG_DEBUG, LSQLM_EVENT)) 981 for ( ; i < (int) n_to_send; ++i) 982 EV_LOG_PACKET_NOT_SENT(batch->conns[i]->cn_cid, batch->packets[i]); 983 /* Return packets to the connection in reverse order so that the packet 984 * ordering is maintained. 985 */ 986 for (i = (int) n_to_send - 1; i >= n_sent; --i) 987 { 988 batch->conns[i]->cn_if->ci_packet_not_sent(batch->conns[i], 989 batch->packets[i]); 990 if (!(batch->conns[i]->cn_flags & (LSCONN_COI_ACTIVE|LSCONN_EVANESCENT))) 991 coi_reactivate(conns_iter, batch->conns[i]); 992 } 993 return n_sent; 994} 995 996 997/* Return 1 if went past deadline, 0 otherwise */ 998static int 999check_deadline (lsquic_engine_t *engine) 1000{ 1001 if (engine->pub.enp_settings.es_proc_time_thresh && 1002 lsquic_time_now() > engine->deadline) 1003 { 1004 LSQ_INFO("went past threshold of %u usec, stop sending", 1005 engine->pub.enp_settings.es_proc_time_thresh); 1006 engine->flags |= ENG_PAST_DEADLINE; 1007 return 1; 1008 } 1009 else 1010 return 0; 1011} 1012 1013 1014static void 1015send_packets_out (struct lsquic_engine *engine, 1016 struct conns_stailq *closed_conns) 1017{ 1018 unsigned n, w, n_sent, n_batches_sent; 1019 lsquic_packet_out_t *packet_out; 1020 lsquic_conn_t *conn; 1021 struct out_batch *const batch = &engine->out_batch; 1022 struct conns_out_iter conns_iter; 1023 int shrink, deadline_exceeded; 1024 1025 coi_init(&conns_iter, engine); 1026 n_batches_sent = 0; 1027 n_sent = 0, n = 0; 1028 shrink = 0; 1029 deadline_exceeded = 0; 1030 1031 while ((conn = coi_next(&conns_iter))) 1032 { 1033 packet_out = conn->cn_if->ci_next_packet_to_send(conn); 1034 if (!packet_out) { 1035 LSQ_DEBUG("batched all outgoing packets for conn %"PRIu64, 1036 conn->cn_cid); 1037 coi_deactivate(&conns_iter, conn); 1038 continue; 1039 } 1040 if (!(packet_out->po_flags & (PO_ENCRYPTED|PO_NOENCRYPT))) 1041 { 1042 switch (encrypt_packet(engine, conn, packet_out)) 1043 { 1044 case ENCPA_NOMEM: 1045 /* Send what we have and wait for a more opportune moment */ 1046 conn->cn_if->ci_packet_not_sent(conn, packet_out); 1047 goto end_for; 1048 case ENCPA_BADCRYPT: 1049 /* This is pretty bad: close connection immediately */ 1050 conn->cn_if->ci_packet_not_sent(conn, packet_out); 1051 LSQ_INFO("conn %"PRIu64" has unsendable packets", conn->cn_cid); 1052 if (!(conn->cn_flags & LSCONN_EVANESCENT)) 1053 { 1054 if (!(conn->cn_flags & LSCONN_CLOSING)) 1055 { 1056 STAILQ_INSERT_TAIL(closed_conns, conn, cn_next_closed_conn); 1057 engine_incref_conn(conn, LSCONN_CLOSING); 1058 if (conn->cn_flags & LSCONN_HASHED) 1059 remove_conn_from_hash(engine, conn); 1060 } 1061 coi_remove(&conns_iter, conn); 1062 } 1063 continue; 1064 case ENCPA_OK: 1065 break; 1066 } 1067 } 1068 LSQ_DEBUG("batched packet %"PRIu64" for connection %"PRIu64, 1069 packet_out->po_packno, conn->cn_cid); 1070 assert(conn->cn_flags & LSCONN_HAS_PEER_SA); 1071 if (packet_out->po_flags & PO_ENCRYPTED) 1072 { 1073 batch->outs[n].buf = packet_out->po_enc_data; 1074 batch->outs[n].sz = packet_out->po_enc_data_sz; 1075 } 1076 else 1077 { 1078 batch->outs[n].buf = packet_out->po_data; 1079 batch->outs[n].sz = packet_out->po_data_sz; 1080 } 1081 batch->outs [n].peer_ctx = conn->cn_peer_ctx; 1082 batch->outs [n].local_sa = (struct sockaddr *) conn->cn_local_addr; 1083 batch->outs [n].dest_sa = (struct sockaddr *) conn->cn_peer_addr; 1084 batch->conns [n] = conn; 1085 batch->packets[n] = packet_out; 1086 ++n; 1087 if (n == engine->batch_size) 1088 { 1089 n = 0; 1090 w = send_batch(engine, &conns_iter, batch, engine->batch_size); 1091 ++n_batches_sent; 1092 n_sent += w; 1093 if (w < engine->batch_size) 1094 { 1095 shrink = 1; 1096 break; 1097 } 1098 deadline_exceeded = check_deadline(engine); 1099 if (deadline_exceeded) 1100 break; 1101 grow_batch_size(engine); 1102 } 1103 } 1104 end_for: 1105 1106 if (n > 0) { 1107 w = send_batch(engine, &conns_iter, batch, n); 1108 n_sent += w; 1109 shrink = w < n; 1110 ++n_batches_sent; 1111 deadline_exceeded = check_deadline(engine); 1112 } 1113 1114 if (shrink) 1115 shrink_batch_size(engine); 1116 else if (n_batches_sent > 1 && !deadline_exceeded) 1117 grow_batch_size(engine); 1118 1119 coi_reheap(&conns_iter, engine); 1120 1121 LSQ_DEBUG("%s: sent %u packet%.*s", __func__, n_sent, n_sent != 1, "s"); 1122} 1123 1124 1125int 1126lsquic_engine_has_unsent_packets (lsquic_engine_t *engine) 1127{ 1128 return lsquic_mh_count(&engine->conns_out) > 0 1129 ; 1130} 1131 1132 1133static void 1134reset_deadline (lsquic_engine_t *engine, lsquic_time_t now) 1135{ 1136 engine->deadline = now + engine->pub.enp_settings.es_proc_time_thresh; 1137 engine->flags &= ~ENG_PAST_DEADLINE; 1138} 1139 1140 1141/* TODO: this is a user-facing function, account for load */ 1142void 1143lsquic_engine_send_unsent_packets (lsquic_engine_t *engine) 1144{ 1145 lsquic_conn_t *conn; 1146 struct conns_stailq closed_conns; 1147 1148 STAILQ_INIT(&closed_conns); 1149 reset_deadline(engine, lsquic_time_now()); 1150 1151 send_packets_out(engine, &closed_conns); 1152 1153 while ((conn = STAILQ_FIRST(&closed_conns))) { 1154 STAILQ_REMOVE_HEAD(&closed_conns, cn_next_closed_conn); 1155 (void) engine_decref_conn(engine, conn, LSCONN_CLOSING); 1156 } 1157 1158} 1159 1160 1161static void 1162process_connections (lsquic_engine_t *engine, conn_iter_f next_conn, 1163 lsquic_time_t now) 1164{ 1165 lsquic_conn_t *conn; 1166 enum tick_st tick_st; 1167 unsigned i; 1168 lsquic_time_t next_tick_time; 1169 struct conns_stailq closed_conns, ticked_conns; 1170 1171 eng_hist_tick(&engine->history, now); 1172 1173 STAILQ_INIT(&closed_conns); 1174 STAILQ_INIT(&ticked_conns); 1175 reset_deadline(engine, now); 1176 1177 i = 0; 1178 while ((conn = next_conn(engine)) 1179 ) 1180 { 1181 tick_st = conn->cn_if->ci_tick(conn, now); 1182 conn->cn_last_ticked = now + i /* Maintain relative order */ ++; 1183 if (tick_st & TICK_SEND) 1184 { 1185 if (!(conn->cn_flags & LSCONN_HAS_OUTGOING)) 1186 { 1187 lsquic_mh_insert(&engine->conns_out, conn, conn->cn_last_sent); 1188 engine_incref_conn(conn, LSCONN_HAS_OUTGOING); 1189 } 1190 } 1191 if (tick_st & TICK_CLOSE) 1192 { 1193 STAILQ_INSERT_TAIL(&closed_conns, conn, cn_next_closed_conn); 1194 engine_incref_conn(conn, LSCONN_CLOSING); 1195 if (conn->cn_flags & LSCONN_HASHED) 1196 remove_conn_from_hash(engine, conn); 1197 } 1198 else 1199 STAILQ_INSERT_TAIL(&ticked_conns, conn, cn_next_ticked); 1200 } 1201 1202 if (lsquic_engine_has_unsent_packets(engine)) 1203 send_packets_out(engine, &closed_conns); 1204 1205 while ((conn = STAILQ_FIRST(&closed_conns))) { 1206 STAILQ_REMOVE_HEAD(&closed_conns, cn_next_closed_conn); 1207 (void) engine_decref_conn(engine, conn, LSCONN_CLOSING); 1208 } 1209 1210 /* TODO Heapification can be optimized by switching to the Floyd method: 1211 * https://en.wikipedia.org/wiki/Binary_heap#Building_a_heap 1212 */ 1213 while ((conn = STAILQ_FIRST(&ticked_conns))) 1214 { 1215 STAILQ_REMOVE_HEAD(&ticked_conns, cn_next_ticked); 1216 if (!(conn->cn_flags & LSCONN_TICKABLE) 1217 && conn->cn_if->ci_is_tickable(conn)) 1218 { 1219 lsquic_mh_insert(&engine->conns_tickable, conn, conn->cn_last_ticked); 1220 engine_incref_conn(conn, LSCONN_TICKABLE); 1221 } 1222 else if (!(conn->cn_flags & LSCONN_ATTQ)) 1223 { 1224 next_tick_time = conn->cn_if->ci_next_tick_time(conn); 1225 if (next_tick_time) 1226 { 1227 if (0 == attq_add(engine->attq, conn, next_tick_time)) 1228 engine_incref_conn(conn, LSCONN_ATTQ); 1229 } 1230 else 1231 assert(0); 1232 } 1233 } 1234 1235} 1236 1237 1238/* Return 0 if packet is being processed by a real connection, 1 if the 1239 * packet was processed, but not by a connection, and -1 on error. 1240 */ 1241int 1242lsquic_engine_packet_in (lsquic_engine_t *engine, 1243 const unsigned char *packet_in_data, size_t packet_in_size, 1244 const struct sockaddr *sa_local, const struct sockaddr *sa_peer, 1245 void *peer_ctx) 1246{ 1247 struct packin_parse_state ppstate; 1248 lsquic_packet_in_t *packet_in; 1249 1250 if (packet_in_size > QUIC_MAX_PACKET_SZ) 1251 { 1252 LSQ_DEBUG("Cannot handle packet_in_size(%zd) > %d packet incoming " 1253 "packet's header", packet_in_size, QUIC_MAX_PACKET_SZ); 1254 errno = E2BIG; 1255 return -1; 1256 } 1257 1258 packet_in = lsquic_mm_get_packet_in(&engine->pub.enp_mm); 1259 if (!packet_in) 1260 return -1; 1261 1262 /* Library does not modify packet_in_data, it is not referenced after 1263 * this function returns and subsequent release of pi_data is guarded 1264 * by PI_OWN_DATA flag. 1265 */ 1266 packet_in->pi_data = (unsigned char *) packet_in_data; 1267 if (0 != parse_packet_in_begin(packet_in, packet_in_size, 1268 engine->flags & ENG_SERVER, &ppstate)) 1269 { 1270 LSQ_DEBUG("Cannot parse incoming packet's header"); 1271 lsquic_mm_put_packet_in(&engine->pub.enp_mm, packet_in); 1272 errno = EINVAL; 1273 return -1; 1274 } 1275 1276 packet_in->pi_received = lsquic_time_now(); 1277 eng_hist_inc(&engine->history, packet_in->pi_received, sl_packets_in); 1278 return process_packet_in(engine, packet_in, &ppstate, sa_local, sa_peer, 1279 peer_ctx); 1280} 1281 1282 1283#if __GNUC__ && !defined(NDEBUG) 1284__attribute__((weak)) 1285#endif 1286unsigned 1287lsquic_engine_quic_versions (const lsquic_engine_t *engine) 1288{ 1289 return engine->pub.enp_settings.es_versions; 1290} 1291 1292 1293int 1294lsquic_engine_earliest_adv_tick (lsquic_engine_t *engine, int *diff) 1295{ 1296 const lsquic_time_t *next_time; 1297 lsquic_time_t now; 1298 1299 if (((engine->flags & ENG_PAST_DEADLINE) 1300 && lsquic_mh_count(&engine->conns_out)) 1301 || lsquic_mh_count(&engine->conns_tickable)) 1302 { 1303 *diff = 0; 1304 return 1; 1305 } 1306 1307 next_time = attq_next_time(engine->attq); 1308 if (!next_time) 1309 return 0; 1310 1311 now = lsquic_time_now(); 1312 *diff = (int) ((int64_t) *next_time - (int64_t) now); 1313 return 1; 1314} 1315 1316 1317unsigned 1318lsquic_engine_count_attq (lsquic_engine_t *engine, int from_now) 1319{ 1320 lsquic_time_t now; 1321 now = lsquic_time_now(); 1322 if (from_now < 0) 1323 now -= from_now; 1324 else 1325 now += from_now; 1326 return attq_count_before(engine->attq, now); 1327} 1328