/* Copyright (c) 2017 LiteSpeed Technologies Inc. See LICENSE. */ /* * lsquic_full_conn.c -- A "full" connection object has full functionality */ #include #include #include #include #include #include #include #include #include #include #include "lsquic_types.h" #include "lsquic.h" #include "lsquic_alarmset.h" #include "lsquic_packet_common.h" #include "lsquic_parse.h" #include "lsquic_packet_in.h" #include "lsquic_packet_out.h" #include "lsquic_rechist.h" #include "lsquic_util.h" #include "lsquic_conn_flow.h" #include "lsquic_sfcw.h" #include "lsquic_stream.h" #include "lsquic_senhist.h" #include "lsquic_rtt.h" #include "lsquic_cubic.h" #include "lsquic_pacer.h" #include "lsquic_send_ctl.h" #include "lsquic_set.h" #include "lsquic_malo.h" #include "lsquic_chsk_stream.h" #include "lsquic_str.h" #include "lsquic_qtags.h" #include "lsquic_handshake.h" #include "lsquic_headers_stream.h" #include "lsquic_frame_common.h" #include "lsquic_frame_reader.h" #include "lsquic_mm.h" #include "lsquic_engine_public.h" #include "lsquic_spi.h" #include "lsquic_ev_log.h" #include "lsquic_version.h" #include "lsquic_hash.h" #include "lsquic_conn.h" #include "lsquic_conn_public.h" #include "lsquic_ver_neg.h" #include "lsquic_full_conn.h" #define LSQUIC_LOGGER_MODULE LSQLM_CONN #define LSQUIC_LOG_CONN_ID conn->fc_conn.cn_cid #include "lsquic_logger.h" enum { STREAM_IF_STD, STREAM_IF_HSK, STREAM_IF_HDR, N_STREAM_IFS }; #define MAX_ANY_PACKETS_SINCE_LAST_ACK 20 #define MAX_RETR_PACKETS_SINCE_LAST_ACK 2 #define ACK_TIMEOUT 25000 #define TIME_BETWEEN_PINGS 15000000 #define IDLE_TIMEOUT 30000000 /* IMPORTANT: Keep values of FC_SERVER and FC_HTTP same as LSENG_SERVER * and LSENG_HTTP. */ enum full_conn_flags { FC_SERVER = LSENG_SERVER, /* Server mode */ FC_HTTP = LSENG_HTTP, /* HTTP mode */ FC_TIMED_OUT = (1 << 2), FC_ERROR = (1 << 3), FC_ABORTED = (1 << 4), FC_CLOSING = (1 << 5), /* Closing */ FC_SEND_PING = (1 << 6), /* PING frame scheduled */ FC_NSTP = (1 << 7), /* NSTP mode */ FC_SEND_GOAWAY = (1 << 8), FC_SEND_WUF = (1 << 9), FC_SEND_STOP_WAITING = (1 <<10), FC_ACK_QUEUED = (1 <<11), FC_ACK_HAD_MISS = (1 <<12), /* Last ACK frame had missing packets. */ FC_CREATED_OK = (1 <<13), FC_RECV_CLOSE = (1 <<14), /* Received CONNECTION_CLOSE frame */ FC_GOING_AWAY = (1 <<15), /* Do not accept or create new streams */ FC_GOAWAY_SENT = (1 <<16), /* Only send GOAWAY once */ FC_SUPPORT_PUSH = (1 <<17), FC_GOT_PRST = (1 <<18), /* Received public reset packet */ FC_FIRST_TICK = (1 <<19), FC_TICK_CLOSE = (1 <<20), /* We returned TICK_CLOSE */ }; #define FC_IMMEDIATE_CLOSE_FLAGS \ (FC_TIMED_OUT|FC_ERROR|FC_ABORTED) #if LSQUIC_KEEP_STREAM_HISTORY #define KEEP_CLOSED_STREAM_HISTORY 0 #endif #if KEEP_CLOSED_STREAM_HISTORY struct stream_history { uint32_t shist_stream_id; enum stream_flags shist_stream_flags; unsigned char shist_hist_buf[1 << SM_HIST_BITS]; }; #define SHIST_BITS 5 #define SHIST_MASK ((1 << SHIST_BITS) - 1) #endif struct full_conn { struct lsquic_conn fc_conn; struct lsquic_hash *fc_streams; struct lsquic_rechist fc_rechist; struct { const struct lsquic_stream_if *stream_if; void *stream_if_ctx; } fc_stream_ifs[N_STREAM_IFS]; lsquic_conn_ctx_t *fc_conn_ctx; struct lsquic_send_ctl fc_send_ctl; struct lsquic_conn_public fc_pub; lsquic_alarmset_t fc_alset; lsquic_set32_t fc_closed_stream_ids[2]; const struct lsquic_engine_settings *fc_settings; struct lsquic_engine_public *fc_enpub; lsquic_packno_t fc_max_ack_packno; lsquic_packno_t fc_max_swf_packno; struct { unsigned max_streams_in; unsigned max_streams_out; unsigned max_conn_send; unsigned max_stream_send; } fc_cfg; enum full_conn_flags fc_flags; /* Number of packets received since last ACK sent: */ unsigned fc_n_slack_all; /* Number ackable packets received since last ACK was sent: */ unsigned fc_n_slack_akbl; unsigned fc_n_delayed_streams; unsigned fc_n_cons_unretx; uint32_t fc_last_stream_id; uint32_t fc_max_peer_stream_id; uint32_t fc_goaway_stream_id; struct ver_neg fc_ver_neg; union { struct client_hsk_ctx client; } fc_hsk_ctx; #if FULL_CONN_STATS struct { unsigned n_all_packets_in, n_packets_out, n_undec_packets, n_dup_packets, n_err_packets; unsigned long stream_data_sz; } fc_stats; #endif #if KEEP_CLOSED_STREAM_HISTORY /* Rolling log of histories of closed streams. Older entries are * overwritten. */ struct stream_history fc_stream_histories[1 << SHIST_BITS]; unsigned fc_stream_hist_idx; #endif }; #define ABORT_WITH_FLAG(conn, flag, errmsg...) do { \ (conn)->fc_flags |= flag; \ LSQ_ERROR("Abort connection: " errmsg); \ } while (0) #define ABORT_ERROR(errmsg...) ABORT_WITH_FLAG(conn, FC_ERROR, errmsg) #define ABORT_TIMEOUT(errmsg...) ABORT_WITH_FLAG(conn, FC_TIMED_OUT, errmsg) static void idle_alarm_expired (void *ctx, lsquic_time_t expiry, lsquic_time_t now); static void ping_alarm_expired (void *ctx, lsquic_time_t expiry, lsquic_time_t now); static void handshake_alarm_expired (void *ctx, lsquic_time_t expiry, lsquic_time_t now); static void ack_alarm_expired (void *ctx, lsquic_time_t expiry, lsquic_time_t now); static lsquic_stream_t * new_stream (struct full_conn *conn, uint32_t stream_id); static void reset_ack_state (struct full_conn *conn); static const struct headers_stream_callbacks headers_callbacks; #if KEEP_CLOSED_STREAM_HISTORY static void save_stream_history (struct full_conn *conn, const lsquic_stream_t *stream) { sm_hist_idx_t idx; struct stream_history *const shist = &conn->fc_stream_histories[ conn->fc_stream_hist_idx++ & SHIST_MASK ]; shist->shist_stream_id = stream->id; shist->shist_stream_flags = stream->stream_flags; idx = stream->sm_hist_idx & SM_HIST_IDX_MASK; if ('\0' == stream->sm_hist_buf[ idx ]) memcpy(shist->shist_hist_buf, stream->sm_hist_buf, idx + 1); else { memcpy(shist->shist_hist_buf, stream->sm_hist_buf + idx, sizeof(stream->sm_hist_buf) - idx); memcpy(shist->shist_hist_buf + sizeof(shist->shist_hist_buf) - idx, stream->sm_hist_buf, idx); } } static const struct stream_history * find_stream_history (const struct full_conn *conn, uint32_t stream_id) { const struct stream_history *shist; const struct stream_history *const shist_end = conn->fc_stream_histories + (1 << SHIST_BITS); for (shist = conn->fc_stream_histories; shist < shist_end; ++shist) if (shist->shist_stream_id == stream_id) return shist; return NULL; } # define SAVE_STREAM_HISTORY(conn, stream) save_stream_history(conn, stream) #else # define SAVE_STREAM_HISTORY(conn, stream) #endif static unsigned highest_bit_set (unsigned sz) { #if __GNUC__ unsigned clz = __builtin_clz(sz); return 31 - clz; #else unsigned n, y; n = 32; y = sz >> 16; if (y) { n -= 16; sz = y; } y = sz >> 8; if (y) { n -= 8; sz = y; } y = sz >> 4; if (y) { n -= 4; sz = y; } y = sz >> 2; if (y) { n -= 2; sz = y; } y = sz >> 1; if (y) return 31 - n + 2; return 31 - n + sz; #endif } static void set_versions (struct full_conn *conn, unsigned versions) { conn->fc_ver_neg.vn_supp = versions; conn->fc_ver_neg.vn_ver = highest_bit_set(versions); conn->fc_ver_neg.vn_buf = lsquic_ver2tag(conn->fc_ver_neg.vn_ver); conn->fc_conn.cn_version = conn->fc_ver_neg.vn_ver; LSQ_DEBUG("negotiating version %s", lsquic_ver2str[conn->fc_ver_neg.vn_ver]); } static void init_ver_neg (struct full_conn *conn, unsigned versions) { set_versions(conn, versions); conn->fc_ver_neg.vn_tag = &conn->fc_ver_neg.vn_buf; conn->fc_ver_neg.vn_state = VN_START; } /* If peer supplies odd values, we abort the connection immediately rather * that wait for it to finish "naturally" due to inability to send things. */ static void conn_on_peer_config (struct full_conn *conn, unsigned peer_cfcw, unsigned peer_sfcw, unsigned max_streams_out) { lsquic_stream_t *stream; struct lsquic_hash_elem *el; LSQ_INFO("Applying peer config: cfcw: %u; sfcw: %u; # streams: %u", peer_cfcw, peer_sfcw, max_streams_out); if (peer_cfcw < conn->fc_pub.conn_cap.cc_sent) { ABORT_ERROR("peer specified CFCW=%u bytes, which is smaller than " "the amount of data already sent on this connection (%"PRIu64 " bytes)", peer_cfcw, conn->fc_pub.conn_cap.cc_sent); return; } conn->fc_cfg.max_streams_out = max_streams_out; conn->fc_pub.conn_cap.cc_max = peer_cfcw; for (el = lsquic_hash_first(conn->fc_streams); el; el = lsquic_hash_next(conn->fc_streams)) { stream = lsquic_hashelem_getdata(el); if (0 != lsquic_stream_set_max_send_off(stream, peer_sfcw)) { ABORT_ERROR("cannot set peer-supplied SFCW=%u on stream %u", peer_sfcw, stream->id); return; } } conn->fc_cfg.max_stream_send = peer_sfcw; } static int send_smhl (const struct full_conn *conn) { uint32_t smhl; return conn->fc_conn.cn_enc_session && (conn->fc_conn.cn_flags & LSCONN_HANDSHAKE_DONE) && 0 == conn->fc_conn.cn_esf->esf_get_peer_setting( conn->fc_conn.cn_enc_session, QTAG_SMHL, &smhl) && 1 == smhl; } /* Once handshake has been completed, send settings to peer if appropriate. */ static void maybe_send_settings (struct full_conn *conn) { struct lsquic_http2_setting settings[2]; unsigned n_settings = 0; if (conn->fc_settings->es_max_header_list_size && send_smhl(conn)) { settings[n_settings].id = SETTINGS_MAX_HEADER_LIST_SIZE; settings[n_settings].value = conn->fc_settings->es_max_header_list_size; LSQ_DEBUG("sending settings SETTINGS_MAX_HEADER_LIST_SIZE=%u", settings[n_settings].value); ++n_settings; } if (!(conn->fc_flags & FC_SERVER) && !conn->fc_settings->es_support_push) { settings[n_settings].id = SETTINGS_ENABLE_PUSH; settings[n_settings].value = 0; LSQ_DEBUG("sending settings SETTINGS_ENABLE_PUSH=%u", settings[n_settings].value); ++n_settings; } if (n_settings) { if (0 != lsquic_headers_stream_send_settings(conn->fc_pub.hs, settings, n_settings)) ABORT_ERROR("could not send settings"); } else LSQ_DEBUG("not sending any settings"); } static int apply_peer_settings (struct full_conn *conn) { uint32_t cfcw, sfcw, mids; unsigned n; const struct { uint32_t tag; uint32_t *val; const char *tag_str; } tags[] = { { QTAG_CFCW, &cfcw, "CFCW", }, { QTAG_SFCW, &sfcw, "SFCW", }, { QTAG_MIDS, &mids, "MIDS", }, }; #ifndef NDEBUG if (getenv("LSQUIC_TEST_ENGINE_DTOR")) return 0; #endif for (n = 0; n < sizeof(tags) / sizeof(tags[0]); ++n) if (0 != conn->fc_conn.cn_esf->esf_get_peer_setting( conn->fc_conn.cn_enc_session, tags[n].tag, tags[n].val)) { LSQ_INFO("peer did not supply value for %s", tags[n].tag_str); return -1; } LSQ_DEBUG("peer settings: CFCW: %u; SFCW: %u; MIDS: %u", cfcw, sfcw, mids); conn_on_peer_config(conn, cfcw, sfcw, mids); if (conn->fc_flags & FC_HTTP) maybe_send_settings(conn); return 0; } static const struct conn_iface full_conn_iface; static struct full_conn * new_conn_common (lsquic_cid_t cid, struct lsquic_engine_public *enpub, const struct lsquic_stream_if *stream_if, void *stream_if_ctx, unsigned flags, unsigned short max_packet_size) { struct full_conn *conn; lsquic_stream_t *headers_stream; int saved_errno; assert(0 == (flags & ~(FC_SERVER|FC_HTTP))); conn = calloc(1, sizeof(*conn)); if (!conn) return NULL; headers_stream = NULL; conn->fc_conn.cn_cid = cid; conn->fc_conn.cn_pack_size = max_packet_size; conn->fc_flags = flags; conn->fc_enpub = enpub; conn->fc_pub.enpub = enpub; conn->fc_pub.mm = &enpub->enp_mm; conn->fc_pub.lconn = &conn->fc_conn; conn->fc_pub.send_ctl = &conn->fc_send_ctl; conn->fc_pub.packet_out_malo = lsquic_malo_create(sizeof(struct lsquic_packet_out)); conn->fc_stream_ifs[STREAM_IF_STD].stream_if = stream_if; conn->fc_stream_ifs[STREAM_IF_STD].stream_if_ctx = stream_if_ctx; conn->fc_settings = &enpub->enp_settings; /* Calculate maximum number of incoming streams using the same mechanism * and parameters as found in Chrome: */ conn->fc_cfg.max_streams_in = (unsigned) ((float) enpub->enp_settings.es_max_streams_in * 1.1f); if (conn->fc_cfg.max_streams_in < enpub->enp_settings.es_max_streams_in + 10) conn->fc_cfg.max_streams_in = enpub->enp_settings.es_max_streams_in + 10; /* `max_streams_out' gets reset when handshake is complete and we * learn of peer settings. 100 seems like a sane default value * because it is what other implementations use. In server mode, * we do not open any streams until the handshake is complete; in * client mode, we are limited to 98 outgoing requests alongside * handshake and headers streams. */ conn->fc_cfg.max_streams_out = 100; TAILQ_INIT(&conn->fc_pub.sending_streams); TAILQ_INIT(&conn->fc_pub.rw_streams); TAILQ_INIT(&conn->fc_pub.service_streams); lsquic_conn_cap_init(&conn->fc_pub.conn_cap, LSQUIC_MIN_FCW); lsquic_alarmset_init(&conn->fc_alset, cid); lsquic_alarmset_init_alarm(&conn->fc_alset, AL_IDLE, idle_alarm_expired, conn); lsquic_alarmset_init_alarm(&conn->fc_alset, AL_ACK, ack_alarm_expired, conn); lsquic_alarmset_init_alarm(&conn->fc_alset, AL_PING, ping_alarm_expired, conn); lsquic_alarmset_init_alarm(&conn->fc_alset, AL_HANDSHAKE, handshake_alarm_expired, conn); lsquic_set32_init(&conn->fc_closed_stream_ids[0]); lsquic_set32_init(&conn->fc_closed_stream_ids[1]); lsquic_cfcw_init(&conn->fc_pub.cfcw, &conn->fc_pub, conn->fc_settings->es_cfcw); lsquic_send_ctl_init(&conn->fc_send_ctl, &conn->fc_alset, conn->fc_enpub, &conn->fc_ver_neg, &conn->fc_pub, conn->fc_conn.cn_pack_size); conn->fc_streams = lsquic_hash_create(); if (!conn->fc_streams) goto cleanup_on_error; lsquic_rechist_init(&conn->fc_rechist, cid); if (conn->fc_flags & FC_HTTP) { conn->fc_pub.hs = lsquic_headers_stream_new( !!(conn->fc_flags & FC_SERVER), conn->fc_pub.mm, conn->fc_settings, &headers_callbacks, conn); if (!conn->fc_pub.hs) goto cleanup_on_error; conn->fc_stream_ifs[STREAM_IF_HDR].stream_if = lsquic_headers_stream_if; conn->fc_stream_ifs[STREAM_IF_HDR].stream_if_ctx = conn->fc_pub.hs; headers_stream = new_stream(conn, LSQUIC_STREAM_HEADERS); if (!headers_stream) goto cleanup_on_error; } else { conn->fc_stream_ifs[STREAM_IF_HDR].stream_if = stream_if; conn->fc_stream_ifs[STREAM_IF_HDR].stream_if_ctx = stream_if_ctx; } if (conn->fc_settings->es_support_push) conn->fc_flags |= FC_SUPPORT_PUSH; conn->fc_conn.cn_if = &full_conn_iface; return conn; cleanup_on_error: saved_errno = errno; if (conn->fc_streams) lsquic_hash_destroy(conn->fc_streams); lsquic_rechist_cleanup(&conn->fc_rechist); if (conn->fc_flags & FC_HTTP) { if (conn->fc_pub.hs) lsquic_headers_stream_destroy(conn->fc_pub.hs); if (headers_stream) lsquic_stream_destroy(headers_stream); } memset(conn, 0, sizeof(*conn)); free(conn); errno = saved_errno; return NULL; } struct lsquic_conn * full_conn_client_new (struct lsquic_engine_public *enpub, const struct lsquic_stream_if *stream_if, void *stream_if_ctx, unsigned flags, const char *hostname, unsigned short max_packet_size) { struct full_conn *conn; enum lsquic_version version; lsquic_cid_t cid; const struct enc_session_funcs *esf; version = highest_bit_set(enpub->enp_settings.es_versions); esf = select_esf_by_ver(version); cid = esf->esf_generate_cid(); conn = new_conn_common(cid, enpub, stream_if, stream_if_ctx, flags, max_packet_size); if (!conn) return NULL; conn->fc_conn.cn_esf = esf; conn->fc_conn.cn_enc_session = conn->fc_conn.cn_esf->esf_create_client(hostname, cid, conn->fc_enpub); if (!conn->fc_conn.cn_enc_session) { LSQ_WARN("could not create enc session: %s", strerror(errno)); conn->fc_conn.cn_if->ci_destroy(&conn->fc_conn); return NULL; } if (conn->fc_flags & FC_HTTP) conn->fc_last_stream_id = LSQUIC_STREAM_HEADERS; /* Client goes 5, 7, 9.... */ else conn->fc_last_stream_id = LSQUIC_STREAM_HANDSHAKE; conn->fc_hsk_ctx.client.lconn = &conn->fc_conn; conn->fc_hsk_ctx.client.mm = &enpub->enp_mm; conn->fc_hsk_ctx.client.ver_neg = &conn->fc_ver_neg; conn->fc_stream_ifs[STREAM_IF_HSK] .stream_if = &lsquic_client_hsk_stream_if; conn->fc_stream_ifs[STREAM_IF_HSK].stream_if_ctx = &conn->fc_hsk_ctx.client; init_ver_neg(conn, conn->fc_settings->es_versions); conn->fc_conn.cn_pf = select_pf_by_ver(conn->fc_ver_neg.vn_ver); if (conn->fc_settings->es_handshake_to) lsquic_alarmset_set(&conn->fc_alset, AL_HANDSHAKE, lsquic_time_now() + conn->fc_settings->es_handshake_to); if (!new_stream(conn, LSQUIC_STREAM_HANDSHAKE)) { LSQ_WARN("could not create handshake stream: %s", strerror(errno)); conn->fc_conn.cn_if->ci_destroy(&conn->fc_conn); return NULL; } conn->fc_flags |= FC_CREATED_OK; conn->fc_conn_ctx = stream_if->on_new_conn(stream_if_ctx, &conn->fc_conn); LSQ_INFO("Created new client connection"); EV_LOG_CONN_EVENT(cid, "created full connection"); return &conn->fc_conn; } static int is_our_stream (const struct full_conn *conn, const lsquic_stream_t *stream) { int is_server = !!(conn->fc_flags & FC_SERVER); return (1 & stream->id) ^ is_server; } static unsigned count_streams (const struct full_conn *conn, int peer) { const lsquic_stream_t *stream; unsigned count; int ours; int is_server; struct lsquic_hash_elem *el; peer = !!peer; is_server = !!(conn->fc_flags & FC_SERVER); count = 0; for (el = lsquic_hash_first(conn->fc_streams); el; el = lsquic_hash_next(conn->fc_streams)) { stream = lsquic_hashelem_getdata(el); ours = (1 & stream->id) ^ is_server; if (ours ^ peer) count += !lsquic_stream_is_closed(stream); } return count; } static void full_conn_ci_destroy (lsquic_conn_t *lconn) { struct full_conn *conn = (struct full_conn *) lconn; struct lsquic_hash_elem *el; struct lsquic_stream *stream; LSQ_DEBUG("destroy connection"); conn->fc_flags |= FC_CLOSING; lsquic_set32_cleanup(&conn->fc_closed_stream_ids[0]); lsquic_set32_cleanup(&conn->fc_closed_stream_ids[1]); for (el = lsquic_hash_first(conn->fc_streams); el; el = lsquic_hash_next(conn->fc_streams)) { stream = lsquic_hashelem_getdata(el); lsquic_stream_destroy(stream); } lsquic_hash_destroy(conn->fc_streams); if (conn->fc_flags & FC_CREATED_OK) conn->fc_stream_ifs[STREAM_IF_STD].stream_if ->on_conn_closed(&conn->fc_conn); if (conn->fc_pub.hs) lsquic_headers_stream_destroy(conn->fc_pub.hs); lsquic_send_ctl_cleanup(&conn->fc_send_ctl); lsquic_rechist_cleanup(&conn->fc_rechist); if (conn->fc_conn.cn_enc_session) conn->fc_conn.cn_esf->esf_destroy(conn->fc_conn.cn_enc_session); lsquic_malo_destroy(conn->fc_pub.packet_out_malo); #if FULL_CONN_STATS LSQ_NOTICE("received %u packets, of which %u were not decryptable, %u were " "dups and %u were errors; sent %u packets, avg stream data per outgoing" " packet is %lu bytes", conn->fc_stats.n_all_packets_in, conn->fc_stats.n_undec_packets, conn->fc_stats.n_dup_packets, conn->fc_stats.n_err_packets, conn->fc_stats.n_packets_out, conn->fc_stats.stream_data_sz / conn->fc_stats.n_packets_out); #endif EV_LOG_CONN_EVENT(LSQUIC_LOG_CONN_ID, "full connection destroyed"); free(conn); } static void conn_mark_stream_closed (struct full_conn *conn, uint32_t stream_id) { /* Because stream IDs are distributed unevenly -- there is a set of odd * stream IDs and a set of even stream IDs -- it is more efficient to * maintain two sets of closed stream IDs. */ int idx = stream_id & 1; stream_id >>= 1; if (0 != lsquic_set32_add(&conn->fc_closed_stream_ids[idx], stream_id)) ABORT_ERROR("could not add element to set: %s", strerror(errno)); } static int conn_is_stream_closed (struct full_conn *conn, uint32_t stream_id) { int idx = stream_id & 1; stream_id >>= 1; return lsquic_set32_has(&conn->fc_closed_stream_ids[idx], stream_id); } static void set_ack_timer (struct full_conn *conn, lsquic_time_t now) { lsquic_alarmset_set(&conn->fc_alset, AL_ACK, now + ACK_TIMEOUT); LSQ_DEBUG("ACK alarm set to %"PRIu64, now + ACK_TIMEOUT); } static void ack_alarm_expired (void *ctx, lsquic_time_t expiry, lsquic_time_t now) { struct full_conn *conn = ctx; LSQ_DEBUG("ACK timer expired (%"PRIu64" < %"PRIu64"): ACK queued", expiry, now); conn->fc_flags |= FC_ACK_QUEUED; } static void try_queueing_ack (struct full_conn *conn, int was_missing, lsquic_time_t now) { if (conn->fc_n_slack_akbl >= MAX_RETR_PACKETS_SINCE_LAST_ACK || (conn->fc_conn.cn_version < LSQVER_039 /* Since Q039 do not ack ACKs */ && conn->fc_n_slack_all >= MAX_ANY_PACKETS_SINCE_LAST_ACK) || ((conn->fc_flags & FC_ACK_HAD_MISS) && was_missing) || lsquic_send_ctl_n_stop_waiting(&conn->fc_send_ctl) > 1) { lsquic_alarmset_unset(&conn->fc_alset, AL_ACK); lsquic_send_ctl_sanity_check(&conn->fc_send_ctl); conn->fc_flags |= FC_ACK_QUEUED; LSQ_DEBUG("ACK queued: ackable: %u; all: %u; had_miss: %d; " "was_missing: %d; n_stop_waiting: %u", conn->fc_n_slack_akbl, conn->fc_n_slack_all, !!(conn->fc_flags & FC_ACK_HAD_MISS), was_missing, lsquic_send_ctl_n_stop_waiting(&conn->fc_send_ctl)); } else if (conn->fc_n_slack_akbl > 0) set_ack_timer(conn, now); } static void reset_ack_state (struct full_conn *conn) { conn->fc_n_slack_all = 0; conn->fc_n_slack_akbl = 0; lsquic_send_ctl_n_stop_waiting_reset(&conn->fc_send_ctl); conn->fc_flags &= ~FC_ACK_QUEUED; lsquic_alarmset_unset(&conn->fc_alset, AL_ACK); lsquic_send_ctl_sanity_check(&conn->fc_send_ctl); LSQ_DEBUG("ACK state reset"); } static lsquic_stream_t * new_stream_ext (struct full_conn *conn, uint32_t stream_id, int if_idx, enum stream_ctor_flags stream_ctor_flags) { lsquic_stream_t *stream = lsquic_stream_new_ext(stream_id, &conn->fc_pub, conn->fc_stream_ifs[if_idx].stream_if, conn->fc_stream_ifs[if_idx].stream_if_ctx, conn->fc_settings->es_sfcw, conn->fc_cfg.max_stream_send, stream_ctor_flags); if (stream) lsquic_hash_insert(conn->fc_streams, &stream->id, sizeof(stream->id), stream); return stream; } static lsquic_stream_t * new_stream (struct full_conn *conn, uint32_t stream_id) { enum stream_ctor_flags flags; int idx; switch (stream_id) { case LSQUIC_STREAM_HANDSHAKE: idx = STREAM_IF_HSK; flags = SCF_DI_AUTOSWITCH|SCF_CALL_ON_NEW; break; case LSQUIC_STREAM_HEADERS: idx = STREAM_IF_HDR; flags = SCF_DI_AUTOSWITCH|SCF_CALL_ON_NEW; if (!(conn->fc_flags & FC_HTTP) && conn->fc_enpub->enp_settings.es_rw_once) flags |= SCF_DISP_RW_ONCE; break; default: idx = STREAM_IF_STD; flags = SCF_DI_AUTOSWITCH|SCF_CALL_ON_NEW; if (conn->fc_enpub->enp_settings.es_rw_once) flags |= SCF_DISP_RW_ONCE; break; } return new_stream_ext(conn, stream_id, idx, flags); } static uint32_t generate_stream_id (struct full_conn *conn) { conn->fc_last_stream_id += 2; return conn->fc_last_stream_id; } unsigned lsquic_conn_n_pending_streams (const lsquic_conn_t *lconn) { struct full_conn *conn = (struct full_conn *) lconn; return conn->fc_n_delayed_streams; } unsigned lsquic_conn_cancel_pending_streams (lsquic_conn_t *lconn, unsigned n) { struct full_conn *conn = (struct full_conn *) lconn; if (n > conn->fc_n_delayed_streams) conn->fc_n_delayed_streams = 0; else conn->fc_n_delayed_streams -= n; return conn->fc_n_delayed_streams; } static int either_side_going_away (const struct full_conn *conn) { return (conn->fc_flags & FC_GOING_AWAY) || (conn->fc_conn.cn_flags & LSCONN_PEER_GOING_AWAY); } void lsquic_conn_make_stream (lsquic_conn_t *lconn) { struct full_conn *conn = (struct full_conn *) lconn; unsigned stream_count = count_streams(conn, 0); if (stream_count < conn->fc_cfg.max_streams_out) { if (!new_stream(conn, generate_stream_id(conn))) ABORT_ERROR("could not create new stream: %s", strerror(errno)); } else if (either_side_going_away(conn)) (void) conn->fc_stream_ifs[STREAM_IF_STD].stream_if->on_new_stream( conn->fc_stream_ifs[STREAM_IF_STD].stream_if_ctx, NULL); else { ++conn->fc_n_delayed_streams; LSQ_DEBUG("delayed stream creation. Backlog size: %u", conn->fc_n_delayed_streams); } } static lsquic_stream_t * find_stream_by_id (struct full_conn *conn, uint32_t stream_id) { struct lsquic_hash_elem *el; el = lsquic_hash_find(conn->fc_streams, &stream_id, sizeof(stream_id)); if (el) return lsquic_hashelem_getdata(el); else return NULL; } lsquic_stream_t * lsquic_conn_get_stream_by_id (lsquic_conn_t *lconn, uint32_t stream_id) { struct full_conn *conn = (struct full_conn *) lconn; return find_stream_by_id(conn, stream_id); } static unsigned count_zero_bytes (const unsigned char *p, size_t len) { const unsigned char *const end = p + len; while (p < end && 0 == *p) ++p; return len - (end - p); } static unsigned process_padding_frame (struct full_conn *conn, lsquic_packet_in_t *packet_in, const unsigned char *p, size_t len) { if (conn->fc_conn.cn_version >= LSQVER_038) return count_zero_bytes(p, len); if (lsquic_is_zero(p, len)) { EV_LOG_PADDING_FRAME_IN(LSQUIC_LOG_CONN_ID, len); return len; } else return 0; } static unsigned process_ping_frame (struct full_conn *conn, lsquic_packet_in_t *packet_in, const unsigned char *p, size_t len) { /* This frame causes ACK frame to be queued, but nothing to do here; * return the length of this frame. */ EV_LOG_PING_FRAME_IN(LSQUIC_LOG_CONN_ID); LSQ_DEBUG("received PING"); return 1; } static int is_peer_initiated (const struct full_conn *conn, uint32_t stream_id) { unsigned is_server = !!(conn->fc_flags & FC_SERVER); int peer_initiated = (stream_id & 1) == is_server; return peer_initiated; } static unsigned process_stream_frame (struct full_conn *conn, lsquic_packet_in_t *packet_in, const unsigned char *p, size_t len) { stream_frame_t *stream_frame; lsquic_stream_t *stream; int parsed_len; stream_frame = lsquic_malo_get(conn->fc_pub.mm->malo.stream_frame); if (!stream_frame) { LSQ_WARN("could not allocate stream frame: %s", strerror(errno)); return 0; } parsed_len = conn->fc_conn.cn_pf->pf_parse_stream_frame(p, len, stream_frame); if (parsed_len < 0) { lsquic_malo_put(stream_frame); return 0; } EV_LOG_STREAM_FRAME_IN(LSQUIC_LOG_CONN_ID, stream_frame); LSQ_DEBUG("Got stream frame for stream #%u", stream_frame->stream_id); if (conn->fc_flags & FC_CLOSING) { LSQ_DEBUG("Connection closing: ignore frame"); lsquic_malo_put(stream_frame); return parsed_len; } stream = find_stream_by_id(conn, stream_frame->stream_id); if (!stream) { if (conn_is_stream_closed(conn, stream_frame->stream_id)) { LSQ_DEBUG("drop frame for closed stream %u", stream_frame->stream_id); lsquic_malo_put(stream_frame); return parsed_len; } if (is_peer_initiated(conn, stream_frame->stream_id)) { unsigned in_count = count_streams(conn, 1); LSQ_DEBUG("number of peer-initiated streams: %u", in_count); if (in_count >= conn->fc_cfg.max_streams_in) { ABORT_ERROR("incoming stream would exceed limit: %u", conn->fc_cfg.max_streams_in); lsquic_malo_put(stream_frame); return 0; } if ((conn->fc_flags & FC_GOING_AWAY) && stream_frame->stream_id > conn->fc_max_peer_stream_id) { LSQ_DEBUG("going away: drop frame for new stream %u", stream_frame->stream_id); lsquic_malo_put(stream_frame); return parsed_len; } } else { ABORT_ERROR("frame for never-initiated stream"); lsquic_malo_put(stream_frame); return 0; } stream = new_stream(conn, stream_frame->stream_id); if (!stream) { ABORT_ERROR("cannot create new stream: %s", strerror(errno)); lsquic_malo_put(stream_frame); return 0; } if (stream_frame->stream_id > conn->fc_max_peer_stream_id) conn->fc_max_peer_stream_id = stream_frame->stream_id; } stream_frame->packet_in = lsquic_packet_in_get(packet_in); if (0 != lsquic_stream_frame_in(stream, stream_frame)) { ABORT_ERROR("cannot insert stream frame"); return 0; } return parsed_len; } static unsigned process_invalid_frame (struct full_conn *conn, lsquic_packet_in_t *packet_in, const unsigned char *p, size_t len) { ABORT_ERROR("invalid frame"); return 0; } /* Reset locally-initiated streams whose IDs is larger than the stream ID * specified in received GOAWAY frame. */ static void reset_local_streams_over_goaway (struct full_conn *conn) { const unsigned is_server = !!(conn->fc_flags & FC_SERVER); lsquic_stream_t *stream; struct lsquic_hash_elem *el; for (el = lsquic_hash_first(conn->fc_streams); el; el = lsquic_hash_next(conn->fc_streams)) { stream = lsquic_hashelem_getdata(el); if (stream->id > conn->fc_goaway_stream_id && ((stream->id & 1) ^ is_server /* Locally initiated? */)) { lsquic_stream_received_goaway(stream); } } } static unsigned process_goaway_frame (struct full_conn *conn, lsquic_packet_in_t *packet_in, const unsigned char *p, size_t len) { uint32_t error_code, stream_id; uint16_t reason_length; const char *reason; const int parsed_len = conn->fc_conn.cn_pf->pf_parse_goaway_frame(p, len, &error_code, &stream_id, &reason_length, &reason); if (parsed_len < 0) return 0; EV_LOG_GOAWAY_FRAME_IN(LSQUIC_LOG_CONN_ID, error_code, stream_id, reason_length, reason); LSQ_DEBUG("received GOAWAY frame, last good stream ID: %u, error code: 0x%X," " reason: `%.*s'", stream_id, error_code, reason_length, reason); if (0 == (conn->fc_conn.cn_flags & LSCONN_PEER_GOING_AWAY)) { conn->fc_conn.cn_flags |= LSCONN_PEER_GOING_AWAY; conn->fc_goaway_stream_id = stream_id; if (conn->fc_stream_ifs[STREAM_IF_STD].stream_if->on_goaway_received) { LSQ_DEBUG("calling on_goaway_received"); conn->fc_stream_ifs[STREAM_IF_STD].stream_if->on_goaway_received( &conn->fc_conn); } else LSQ_DEBUG("on_goaway_received not registered"); reset_local_streams_over_goaway(conn); } else LSQ_DEBUG("ignore duplicate GOAWAY frame"); return parsed_len; } static void log_invalid_ack_frame (struct full_conn *conn, const unsigned char *p, int parsed_len, const struct ack_info *acki) { char *buf; size_t sz; buf = malloc(0x1000); if (buf) { lsquic_senhist_tostr(&conn->fc_send_ctl.sc_senhist, buf, 0x1000); LSQ_WARN("send history: %s", buf); hexdump(p, parsed_len, buf, 0x1000); LSQ_WARN("raw ACK frame:\n%s", buf); free(buf); } else LSQ_WARN("malloc failed"); buf = acki2str(acki, &sz); if (buf) { LSQ_WARN("parsed ACK frame: %.*s", (int) sz, buf); free(buf); } else LSQ_WARN("malloc failed"); } static unsigned process_ack_frame (struct full_conn *conn, lsquic_packet_in_t *packet_in, const unsigned char *p, size_t len) { const int parsed_len = conn->fc_conn.cn_pf->pf_parse_ack_frame(p, len, conn->fc_pub.mm->acki); if (parsed_len < 0) return 0; if (packet_in->pi_packno > conn->fc_max_ack_packno) { EV_LOG_ACK_FRAME_IN(LSQUIC_LOG_CONN_ID, conn->fc_pub.mm->acki); if (0 == lsquic_send_ctl_got_ack(&conn->fc_send_ctl, conn->fc_pub.mm->acki, packet_in->pi_received)) { conn->fc_max_ack_packno = packet_in->pi_packno; if (lsquic_send_ctl_largest_ack2ed(&conn->fc_send_ctl)) lsquic_rechist_stop_wait(&conn->fc_rechist, lsquic_send_ctl_largest_ack2ed(&conn->fc_send_ctl) + 1); } else { log_invalid_ack_frame(conn, p, parsed_len, conn->fc_pub.mm->acki); ABORT_ERROR("Received invalid ACK"); } } else LSQ_DEBUG("Ignore old ack (max %"PRIu64")", conn->fc_max_ack_packno); return parsed_len; } static unsigned process_stop_waiting_frame (struct full_conn *conn, lsquic_packet_in_t *packet_in, const unsigned char *p, size_t len) { lsquic_packno_t least, cutoff; enum lsquic_packno_bits bits; int parsed_len; bits = lsquic_packet_in_packno_bits(packet_in); if (conn->fc_flags & FC_NSTP) { LSQ_DEBUG("NSTP on: ignore STOP_WAITING frame"); parsed_len = conn->fc_conn.cn_pf->pf_skip_stop_waiting_frame(len, bits); if (parsed_len > 0) return (unsigned) parsed_len; else return 0; } parsed_len = conn->fc_conn.cn_pf->pf_parse_stop_waiting_frame(p, len, packet_in->pi_packno, bits, &least); if (parsed_len < 0) return 0; if (packet_in->pi_packno <= conn->fc_max_swf_packno) { LSQ_DEBUG("ignore old STOP_WAITING frame"); return parsed_len; } LSQ_DEBUG("Got STOP_WAITING frame, least unacked: %"PRIu64, least); EV_LOG_STOP_WAITING_FRAME_IN(LSQUIC_LOG_CONN_ID, least); if (least > packet_in->pi_packno) { ABORT_ERROR("received invalid STOP_WAITING: %"PRIu64" is larger " "than the packet number%"PRIu64, least, packet_in->pi_packno); return 0; } cutoff = lsquic_rechist_cutoff(&conn->fc_rechist); if (cutoff && least < cutoff) { ABORT_ERROR("received invalid STOP_WAITING: %"PRIu64" is smaller " "than the cutoff %"PRIu64, least, cutoff); return 0; } conn->fc_max_swf_packno = packet_in->pi_packno; lsquic_rechist_stop_wait(&conn->fc_rechist, least); return parsed_len; } static unsigned process_blocked_frame (struct full_conn *conn, lsquic_packet_in_t *packet_in, const unsigned char *p, size_t len) { uint32_t stream_id; const int parsed_len = conn->fc_conn.cn_pf->pf_parse_blocked_frame(p, len, &stream_id); if (parsed_len < 0) return 0; EV_LOG_BLOCKED_FRAME_IN(LSQUIC_LOG_CONN_ID, stream_id); LSQ_DEBUG("Peer reports stream %u as blocked", stream_id); return parsed_len; } static unsigned process_connection_close_frame (struct full_conn *conn, lsquic_packet_in_t *packet_in, const unsigned char *p, size_t len) { lsquic_stream_t *stream; struct lsquic_hash_elem *el; uint32_t error_code; uint16_t reason_len; uint8_t reason_off; int parsed_len; parsed_len = conn->fc_conn.cn_pf->pf_parse_connect_close_frame(p, len, &error_code, &reason_len, &reason_off); if (parsed_len < 0) return 0; EV_LOG_CONNECTION_CLOSE_FRAME_IN(LSQUIC_LOG_CONN_ID, error_code, (int) reason_len, (const char *) p + reason_off); LSQ_INFO("Received CONNECTION_CLOSE frame (code: %u; reason: %.*s)", error_code, (int) reason_len, (const char *) p + reason_off); conn->fc_flags |= FC_RECV_CLOSE; if (!(conn->fc_flags & FC_CLOSING)) { for (el = lsquic_hash_first(conn->fc_streams); el; el = lsquic_hash_next(conn->fc_streams)) { stream = lsquic_hashelem_getdata(el); lsquic_stream_shutdown_internal(stream); } conn->fc_flags |= FC_CLOSING; } return parsed_len; } static unsigned process_rst_stream_frame (struct full_conn *conn, lsquic_packet_in_t *packet_in, const unsigned char *p, size_t len) { uint32_t stream_id, error_code; uint64_t offset; lsquic_stream_t *stream; const int parsed_len = conn->fc_conn.cn_pf->pf_parse_rst_frame(p, len, &stream_id, &offset, &error_code); if (parsed_len < 0) return 0; EV_LOG_RST_STREAM_FRAME_IN(LSQUIC_LOG_CONN_ID, stream_id, offset, error_code); LSQ_DEBUG("Got RST_STREAM; stream: %u; offset: 0x%"PRIX64, stream_id, offset); if (0 == stream_id) { /* Follow reference implementation and ignore this apparently * invalid frame. */ return parsed_len; } if (LSQUIC_STREAM_HANDSHAKE == stream_id || ((conn->fc_flags & FC_HTTP) && LSQUIC_STREAM_HEADERS == stream_id)) { ABORT_ERROR("received reset on static stream %u", stream_id); return 0; } stream = find_stream_by_id(conn, stream_id); if (!stream) { if (conn_is_stream_closed(conn, stream_id)) { LSQ_DEBUG("got reset frame for closed stream %u", stream_id); return parsed_len; } if (!is_peer_initiated(conn, stream_id)) { ABORT_ERROR("received reset for never-initiated stream %u", stream_id); return 0; } stream = new_stream(conn, stream_id); if (!stream) { ABORT_ERROR("cannot create new stream: %s", strerror(errno)); return 0; } if (stream_id > conn->fc_max_peer_stream_id) conn->fc_max_peer_stream_id = stream_id; } if (0 != lsquic_stream_rst_in(stream, offset, error_code)) { ABORT_ERROR("received invalid RST_STREAM"); return 0; } lsquic_send_ctl_reset_stream(&conn->fc_send_ctl, stream_id); return parsed_len; } static unsigned process_window_update_frame (struct full_conn *conn, lsquic_packet_in_t *packet_in, const unsigned char *p, size_t len) { uint32_t stream_id; uint64_t offset; const int parsed_len = conn->fc_conn.cn_pf->pf_parse_window_update_frame(p, len, &stream_id, &offset); if (parsed_len < 0) return 0; EV_LOG_WINDOW_UPDATE_FRAME_IN(LSQUIC_LOG_CONN_ID, stream_id, offset); if (stream_id) { lsquic_stream_t *stream = find_stream_by_id(conn, stream_id); if (stream) { LSQ_DEBUG("Got window update frame, stream: %u; offset: 0x%"PRIX64, stream_id, offset); lsquic_stream_window_update(stream, offset); } else /* Perhaps a result of lost packets? */ LSQ_DEBUG("Got window update frame for non-existing stream %u " "(offset: 0x%"PRIX64")", stream_id, offset); } else if (offset > conn->fc_pub.conn_cap.cc_max) { conn->fc_pub.conn_cap.cc_max = offset; assert(conn->fc_pub.conn_cap.cc_max >= conn->fc_pub.conn_cap.cc_sent); LSQ_DEBUG("Connection WUF, new offset 0x%"PRIX64, offset); } else LSQ_DEBUG("Throw ouw duplicate connection WUF"); return parsed_len; } typedef unsigned (*process_frame_f)( struct full_conn *, lsquic_packet_in_t *, const unsigned char *p, size_t); static process_frame_f const process_frames[N_QUIC_FRAMES] = { [QUIC_FRAME_ACK] = process_ack_frame, [QUIC_FRAME_BLOCKED] = process_blocked_frame, [QUIC_FRAME_CONNECTION_CLOSE] = process_connection_close_frame, [QUIC_FRAME_GOAWAY] = process_goaway_frame, [QUIC_FRAME_INVALID] = process_invalid_frame, [QUIC_FRAME_PADDING] = process_padding_frame, [QUIC_FRAME_PING] = process_ping_frame, [QUIC_FRAME_RST_STREAM] = process_rst_stream_frame, [QUIC_FRAME_STOP_WAITING] = process_stop_waiting_frame, [QUIC_FRAME_STREAM] = process_stream_frame, [QUIC_FRAME_WINDOW_UPDATE] = process_window_update_frame, }; static unsigned process_packet_frame (struct full_conn *conn, lsquic_packet_in_t *packet_in, const unsigned char *p, size_t len) { enum QUIC_FRAME_TYPE type = conn->fc_conn.cn_pf->pf_parse_frame_type(p[0]); packet_in->pi_frame_types |= 1 << type; return process_frames[type](conn, packet_in, p, len); } static void process_ver_neg_packet (struct full_conn *conn, lsquic_packet_in_t *packet_in) { int s; struct ver_iter vi; lsquic_ver_tag_t ver_tag; enum lsquic_version version; unsigned versions = 0; LSQ_DEBUG("Processing version-negotiation packet"); if (conn->fc_ver_neg.vn_state != VN_START) { LSQ_DEBUG("ignore a likely duplicate version negotiation packet"); return; } for (s = packet_in_ver_first(packet_in, &vi, &ver_tag); s; s = packet_in_ver_next(&vi, &ver_tag)) { version = lsquic_tag2ver(ver_tag); if (version < N_LSQVER) { versions |= 1 << version; LSQ_DEBUG("server supports version %s", lsquic_ver2str[version]); } } if (versions & (1 << conn->fc_ver_neg.vn_ver)) { ABORT_ERROR("server replied with version we support: %s", lsquic_ver2str[conn->fc_ver_neg.vn_ver]); return; } versions &= conn->fc_ver_neg.vn_supp; if (0 == versions) { ABORT_ERROR("client does not support any of the server-specified " "versions"); return; } set_versions(conn, versions); conn->fc_ver_neg.vn_state = VN_IN_PROGRESS; lsquic_send_ctl_expire_all(&conn->fc_send_ctl); } static void reconstruct_packet_number (struct full_conn *conn, lsquic_packet_in_t *packet_in) { lsquic_packno_t cur_packno, max_packno; enum lsquic_packno_bits bits; cur_packno = packet_in->pi_packno; max_packno = lsquic_rechist_largest_packno(&conn->fc_rechist); bits = lsquic_packet_in_packno_bits(packet_in); packet_in->pi_packno = restore_packno(cur_packno, bits, max_packno); LSQ_DEBUG("reconstructed (bits: %u, packno: %"PRIu64", max: %"PRIu64") " "to %"PRIu64"", bits, cur_packno, max_packno, packet_in->pi_packno); } static int conn_decrypt_packet (struct full_conn *conn, lsquic_packet_in_t *packet_in) { return lsquic_conn_decrypt_packet(&conn->fc_conn, conn->fc_enpub, packet_in); } static void parse_regular_packet (struct full_conn *conn, lsquic_packet_in_t *packet_in) { const unsigned char *p, *pend; unsigned len; p = packet_in->pi_data + packet_in->pi_header_sz; pend = packet_in->pi_data + packet_in->pi_data_sz; while (p < pend) { len = process_packet_frame(conn, packet_in, p, pend - p); if (len > 0) p += len; else { ABORT_ERROR("Error parsing frame"); break; } } } static int process_regular_packet (struct full_conn *conn, lsquic_packet_in_t *packet_in) { enum received_st st; int was_missing; reconstruct_packet_number(conn, packet_in); EV_LOG_PACKET_IN(LSQUIC_LOG_CONN_ID, packet_in); #if FULL_CONN_STATS ++conn->fc_stats.n_all_packets_in; #endif /* The packet is decrypted before receive history is updated. This is * done to make sure that a bad packet won't occupy a slot in receive * history and subsequent good packet won't be marked as a duplicate. */ if (0 == (packet_in->pi_flags & PI_DECRYPTED) && 0 != conn_decrypt_packet(conn, packet_in)) { LSQ_INFO("could not decrypt packet"); #if FULL_CONN_STATS ++conn->fc_stats.n_undec_packets; #endif return 0; } st = lsquic_rechist_received(&conn->fc_rechist, packet_in->pi_packno, packet_in->pi_received); switch (st) { case REC_ST_OK: parse_regular_packet(conn, packet_in); if (0 == (conn->fc_flags & FC_ACK_QUEUED)) { was_missing = packet_in->pi_packno != lsquic_rechist_largest_packno(&conn->fc_rechist); conn->fc_n_slack_all += 1; conn->fc_n_slack_akbl += !!(packet_in->pi_frame_types & QFRAME_ACKABLE_MASK); try_queueing_ack(conn, was_missing, packet_in->pi_received); } return 0; case REC_ST_DUP: #if FULL_CONN_STATS ++conn->fc_stats.n_dup_packets; #endif LSQ_INFO("packet %"PRIu64" is a duplicate", packet_in->pi_packno); return 0; default: assert(0); /* Fall through */ case REC_ST_ERR: #if FULL_CONN_STATS ++conn->fc_stats.n_err_packets; #endif LSQ_INFO("error processing packet %"PRIu64, packet_in->pi_packno); return -1; } } static int process_incoming_packet (struct full_conn *conn, lsquic_packet_in_t *packet_in) { LSQ_DEBUG("Processing packet %"PRIu64, packet_in->pi_packno); /* See flowchart in Section 4.1 of [draft-ietf-quic-transport-00]. We test * for the common case first. */ const unsigned flags = lsquic_packet_in_public_flags(packet_in); if (0 == (flags & (PACKET_PUBLIC_FLAGS_RST|PACKET_PUBLIC_FLAGS_VERSION))) { if (conn->fc_ver_neg.vn_tag) { assert(conn->fc_ver_neg.vn_state != VN_END); conn->fc_ver_neg.vn_state = VN_END; conn->fc_ver_neg.vn_tag = NULL; conn->fc_conn.cn_version = conn->fc_ver_neg.vn_ver; conn->fc_conn.cn_flags |= LSCONN_VER_SET; if (conn->fc_conn.cn_version >= LSQVER_037) { assert(!(conn->fc_flags & FC_NSTP)); /* This bit off at start */ if (conn->fc_settings->es_support_nstp) { conn->fc_flags |= FC_NSTP; lsquic_send_ctl_turn_nstp_on(&conn->fc_send_ctl); } } LSQ_DEBUG("end of version negotiation: agreed upon %s", lsquic_ver2str[conn->fc_ver_neg.vn_ver]); } return process_regular_packet(conn, packet_in); } else if (flags & PACKET_PUBLIC_FLAGS_RST) { LSQ_INFO("received public reset packet: aborting connection"); conn->fc_flags |= FC_GOT_PRST; return -1; } else { if (conn->fc_flags & FC_SERVER) return process_regular_packet(conn, packet_in); else if (conn->fc_ver_neg.vn_tag) { process_ver_neg_packet(conn, packet_in); return 0; } else { LSQ_DEBUG("unexpected version negotiation packet: ignore it"); return 0; } } } static void idle_alarm_expired (void *ctx, lsquic_time_t expiry, lsquic_time_t now) { struct full_conn *conn = ctx; LSQ_DEBUG("connection timed out"); conn->fc_flags |= FC_TIMED_OUT; } static void handshake_alarm_expired (void *ctx, lsquic_time_t expiry, lsquic_time_t now) { struct full_conn *conn = ctx; LSQ_DEBUG("connection timed out: handshake timed out"); conn->fc_flags |= FC_TIMED_OUT; } static void ping_alarm_expired (void *ctx, lsquic_time_t expiry, lsquic_time_t now) { struct full_conn *conn = ctx; LSQ_DEBUG("Ping alarm rang: schedule PING frame to be generated"); conn->fc_flags |= FC_SEND_PING; } static void zero_pad_packet (lsquic_packet_out_t *packet_out) { memset(packet_out->po_data + packet_out->po_data_sz, 0, packet_out->po_n_alloc - packet_out->po_data_sz); packet_out->po_data_sz = packet_out->po_n_alloc; packet_out->po_frame_types |= 1 << QUIC_FRAME_PADDING; } #define MAX_STREAM_FRAME_HEADER (1 + 4 + 8 + 2) #define MIN_STREAM_FRAME_PAYLOAD 10 /* Some sane value */ #define MIN(a, b) ((a) < (b) ? (a) : (b)) static lsquic_packet_out_t * get_writeable_packet (struct full_conn *conn, unsigned need_at_least) { lsquic_packet_out_t *packet_out; int is_err; assert(need_at_least <= QUIC_MAX_PAYLOAD_SZ); packet_out = lsquic_send_ctl_get_writeable_packet(&conn->fc_send_ctl, need_at_least, &is_err); if (!packet_out && is_err) ABORT_ERROR("cannot allocate packet: %s", strerror(errno)); return packet_out; } static int generate_wuf_stream (struct full_conn *conn, lsquic_stream_t *stream) { lsquic_packet_out_t *packet_out = get_writeable_packet(conn, QUIC_WUF_SZ); if (!packet_out) return 0; const uint64_t recv_off = lsquic_stream_fc_recv_off(stream); int sz = conn->fc_conn.cn_pf->pf_gen_window_update_frame( packet_out->po_data + packet_out->po_data_sz, lsquic_packet_out_avail(packet_out), stream->id, recv_off); if (sz < 0) { ABORT_ERROR("gen_window_update_frame failed"); return 0; } packet_out->po_data_sz += sz; packet_out->po_frame_types |= 1 << QUIC_FRAME_WINDOW_UPDATE; LSQ_DEBUG("wrote WUF: stream %u; offset 0x%"PRIX64, stream->id, recv_off); return 1; } static void generate_wuf_conn (struct full_conn *conn) { assert(conn->fc_flags & FC_SEND_WUF); lsquic_packet_out_t *packet_out = get_writeable_packet(conn, QUIC_WUF_SZ); if (!packet_out) return; const uint64_t recv_off = lsquic_cfcw_get_fc_recv_off(&conn->fc_pub.cfcw); int sz = conn->fc_conn.cn_pf->pf_gen_window_update_frame( packet_out->po_data + packet_out->po_data_sz, lsquic_packet_out_avail(packet_out), 0, recv_off); if (sz < 0) { ABORT_ERROR("gen_window_update_frame failed"); return; } packet_out->po_data_sz += sz; packet_out->po_frame_types |= 1 << QUIC_FRAME_WINDOW_UPDATE; conn->fc_flags &= ~FC_SEND_WUF; LSQ_DEBUG("wrote connection WUF: offset 0x%"PRIX64, recv_off); } static void generate_goaway_frame (struct full_conn *conn) { int reason_len = 0; lsquic_packet_out_t *packet_out = get_writeable_packet(conn, QUIC_GOAWAY_FRAME_SZ + reason_len); if (!packet_out) return; int sz = conn->fc_conn.cn_pf->pf_gen_goaway_frame( packet_out->po_data + packet_out->po_data_sz, lsquic_packet_out_avail(packet_out), 0, conn->fc_max_peer_stream_id, NULL, reason_len); if (sz < 0) { ABORT_ERROR("gen_goaway_frame failed"); return; } packet_out->po_data_sz += sz; packet_out->po_frame_types |= 1 << QUIC_FRAME_GOAWAY; conn->fc_flags &= ~FC_SEND_GOAWAY; conn->fc_flags |= FC_GOAWAY_SENT; LSQ_DEBUG("wrote GOAWAY frame: stream id: %u", conn->fc_max_peer_stream_id); } static void generate_connection_close_packet (struct full_conn *conn) { lsquic_packet_out_t *packet_out; packet_out = lsquic_send_ctl_new_packet_out(&conn->fc_send_ctl, 0); if (!packet_out) { ABORT_ERROR("cannot allocate packet: %s", strerror(errno)); return; } lsquic_send_ctl_scheduled_one(&conn->fc_send_ctl, packet_out); int sz = conn->fc_conn.cn_pf->pf_gen_connect_close_frame(packet_out->po_data + packet_out->po_data_sz, lsquic_packet_out_avail(packet_out), 16 /* PEER_GOING_AWAY */, NULL, 0); if (sz < 0) { ABORT_ERROR("generate_connection_close_packet failed"); return; } packet_out->po_data_sz += sz; packet_out->po_frame_types |= 1 << QUIC_FRAME_CONNECTION_CLOSE; LSQ_DEBUG("generated CONNECTION_CLOSE frame in its own packet"); } static int generate_blocked_frame (struct full_conn *conn, uint32_t stream_id) { lsquic_packet_out_t *packet_out = get_writeable_packet(conn, QUIC_BLOCKED_FRAME_SZ); if (!packet_out) return 0; int sz = conn->fc_conn.cn_pf->pf_gen_blocked_frame( packet_out->po_data + packet_out->po_data_sz, lsquic_packet_out_avail(packet_out), stream_id); if (sz < 0) { ABORT_ERROR("gen_blocked_frame failed"); return 0; } packet_out->po_data_sz += sz; packet_out->po_frame_types |= 1 << QUIC_FRAME_BLOCKED; LSQ_DEBUG("wrote blocked frame: stream %u", stream_id); return 1; } static int generate_stream_blocked_frame (struct full_conn *conn, lsquic_stream_t *stream) { if (generate_blocked_frame(conn, stream->id)) { lsquic_stream_blocked_frame_sent(stream); return 1; } else return 0; } static int generate_rst_stream_frame (struct full_conn *conn, lsquic_stream_t *stream) { lsquic_packet_out_t *packet_out; int sz, s; packet_out = get_writeable_packet(conn, QUIC_RST_STREAM_SZ); if (!packet_out) return 0; sz = conn->fc_conn.cn_pf->pf_gen_rst_frame( packet_out->po_data + packet_out->po_data_sz, lsquic_packet_out_avail(packet_out), stream->id, stream->tosend_off, stream->error_code); if (sz < 0) { ABORT_ERROR("gen_rst_frame failed"); return 0; } packet_out->po_data_sz += sz; packet_out->po_frame_types |= 1 << QUIC_FRAME_RST_STREAM; s = lsquic_packet_out_add_stream(packet_out, conn->fc_pub.mm, stream, QUIC_FRAME_RST_STREAM, 0); if (s != 0) { ABORT_ERROR("adding stream to packet failed: %s", strerror(errno)); return 0; } lsquic_stream_rst_frame_sent(stream); LSQ_DEBUG("wrote RST: stream %u; offset 0x%"PRIX64"; error code 0x%X", stream->id, stream->tosend_off, stream->error_code); return 1; } static void generate_ping_frame (struct full_conn *conn) { lsquic_packet_out_t *packet_out = get_writeable_packet(conn, 1); if (!packet_out) { LSQ_DEBUG("cannot get writeable packet for PING frame"); return; } int sz = conn->fc_conn.cn_pf->pf_gen_ping_frame( packet_out->po_data + packet_out->po_data_sz, lsquic_packet_out_avail(packet_out)); if (sz < 0) { ABORT_ERROR("gen_blocked_frame failed"); return; } packet_out->po_data_sz += sz; packet_out->po_frame_types |= 1 << QUIC_FRAME_PING; LSQ_DEBUG("wrote PING frame"); } static void generate_stop_waiting_frame (struct full_conn *conn) { assert(conn->fc_flags & FC_SEND_STOP_WAITING); int sz; unsigned packnum_len; lsquic_packno_t least_unacked; lsquic_packet_out_t *packet_out; /* Get packet that has room for the minimum size STOP_WAITING frame: */ packet_out = get_writeable_packet(conn, 1 + packno_bits2len(PACKNO_LEN_1)); if (!packet_out) return; /* Now calculate number of bytes we really need. If there is not enough * room in the current packet, get a new one. */ packnum_len = packno_bits2len(lsquic_packet_out_packno_bits(packet_out)); if ((unsigned) lsquic_packet_out_avail(packet_out) < 1 + packnum_len) { packet_out = get_writeable_packet(conn, 1 + packnum_len); if (!packet_out) return; /* Here, a new packet has been allocated, The number of bytes needed * to represent packet number in the STOP_WAITING frame may have * increased. However, this does not matter, because the newly * allocated packet must have room for a STOP_WAITING frame of any * size. */ } least_unacked = lsquic_send_ctl_smallest_unacked(&conn->fc_send_ctl); sz = conn->fc_conn.cn_pf->pf_gen_stop_waiting_frame( packet_out->po_data + packet_out->po_data_sz, lsquic_packet_out_avail(packet_out), packet_out->po_packno, lsquic_packet_out_packno_bits(packet_out), least_unacked); if (sz < 0) { ABORT_ERROR("gen_stop_waiting_frame failed"); return; } packet_out->po_data_sz += sz; packet_out->po_regen_sz += sz; packet_out->po_frame_types |= 1 << QUIC_FRAME_STOP_WAITING; conn->fc_flags &= ~FC_SEND_STOP_WAITING; LSQ_DEBUG("wrote STOP_WAITING frame: least unacked: %"PRIu64, least_unacked); EV_LOG_GENERATED_STOP_WAITING_FRAME(LSQUIC_LOG_CONN_ID, least_unacked); } static int generate_stream_frame (struct full_conn *conn, lsquic_stream_t *stream) { lsquic_packet_out_t *packet_out; size_t n_to_send, need_at_least; int len, s; unsigned short off; /* Send one packet's worth */ n_to_send = lsquic_stream_tosend_sz(stream); assert(n_to_send > 0 || lsquic_stream_tosend_fin(stream)); /* Otherwise, why are we called? */ need_at_least = MAX_STREAM_FRAME_HEADER + MIN(MIN_STREAM_FRAME_PAYLOAD, n_to_send); packet_out = get_writeable_packet(conn, need_at_least); if (!packet_out) return 0; off = packet_out->po_data_sz; len = conn->fc_conn.cn_pf->pf_gen_stream_frame( packet_out->po_data + packet_out->po_data_sz, lsquic_packet_out_avail(packet_out), stream->id, lsquic_stream_tosend_offset(stream), (gsf_fin_f) lsquic_stream_tosend_fin, (gsf_size_f) lsquic_stream_tosend_sz, (gsf_read_f) lsquic_stream_tosend_read, stream); if (len < 0) { ABORT_ERROR("gen_stream_frame failed"); return 0; } #if FULL_CONN_STATS conn->fc_stats.stream_data_sz += len - conn->fc_conn.cn_pf->pf_parse_stream_frame_header_sz( packet_out->po_data[packet_out->po_data_sz]); #endif EV_LOG_GENERATED_STREAM_FRAME(LSQUIC_LOG_CONN_ID, conn->fc_conn.cn_pf, packet_out->po_data + packet_out->po_data_sz, len); packet_out->po_data_sz += len; packet_out->po_frame_types |= 1 << QUIC_FRAME_STREAM; s = lsquic_packet_out_add_stream(packet_out, conn->fc_pub.mm, stream, QUIC_FRAME_STREAM, off); if (s != 0) { ABORT_ERROR("adding stream to packet failed: %s", strerror(errno)); return 0; } lsquic_stream_stream_frame_sent(stream); LSQ_DEBUG("Put %d bytes of data from stream %u into packet on outgoing " "queue", len, stream->id); return 1; } /* TODO I think we can separate this function into two functions: one that * processes STREAM_SEND_WUF, STREAM_SEND_BLOCKED, and STREAM_SEND_RST * queues, and one that processes STREAM_SEND_DATA queue, as the four flags * are not dependent upon each other. Double-check this and implement. */ static int process_stream_ready_to_send (struct full_conn *conn, lsquic_stream_t *stream, int send_data) { int r = 1, written; if (stream->stream_flags & STREAM_SEND_WUF) r &= generate_wuf_stream(conn, stream); if (send_data && (stream->stream_flags & STREAM_SEND_DATA)) { if (LSQUIC_STREAM_HANDSHAKE == stream->id) { /* Handshake messages are sent in brand-new packets. If handshake * is not complete, the packet is zero-padded. */ lsquic_packet_out_t *packet_out = get_writeable_packet(conn, 0); written = generate_stream_frame(conn, stream); r &= written; if (written) { packet_out->po_flags |= PO_HELLO; LSQ_DEBUG("packet %"PRIu64" is carrying CHLO data", packet_out->po_packno); if (!(conn->fc_conn.cn_flags & LSCONN_HANDSHAKE_DONE)) { zero_pad_packet(packet_out); LSQ_DEBUG("zero-padded packet %"PRIu64, packet_out->po_packno); } } assert(packet_out == lsquic_send_ctl_last_scheduled(&conn->fc_send_ctl)); } else r &= generate_stream_frame(conn, stream); } if (stream->stream_flags & STREAM_SEND_BLOCKED) r &= generate_stream_blocked_frame(conn, stream); if (stream->stream_flags & STREAM_SEND_RST) r &= generate_rst_stream_frame(conn, stream); return r; } /* Return 1 if any STREAM frames were packetized, 0 otherwise. */ static int process_streams_ready_to_send (struct full_conn *conn) { lsquic_stream_t *stream; struct stream_prio_iter spi; int stream_frames_packetized; assert(!TAILQ_EMPTY(&conn->fc_pub.sending_streams)); lsquic_spi_init(&spi, TAILQ_FIRST(&conn->fc_pub.sending_streams), TAILQ_LAST(&conn->fc_pub.sending_streams, lsquic_streams_tailq), (uintptr_t) &TAILQ_NEXT((lsquic_stream_t *) NULL, next_send_stream), STREAM_SENDING_FLAGS, conn->fc_conn.cn_cid, "send"); /* The first iteration takes care of all WINDOW_UPDATE, BLOCKED, and * RST_STREAM frames. After that, we turn on priority level exhaustion * mechanism in the iterator and send data. */ for (stream = lsquic_spi_first(&spi); stream; stream = lsquic_spi_next(&spi)) if (!process_stream_ready_to_send(conn, stream, 0)) return 0; lsquic_spi_exhaust_on(&spi); stream_frames_packetized = 0; for (stream = lsquic_spi_first(&spi); stream; stream = lsquic_spi_next(&spi)) if (process_stream_ready_to_send(conn, stream, 1)) ++stream_frames_packetized; else break; return stream_frames_packetized > 0; } static void service_streams (struct full_conn *conn) { struct lsquic_hash_elem *el; lsquic_stream_t *stream, *next; int n_our_destroyed = 0; for (stream = TAILQ_FIRST(&conn->fc_pub.service_streams); stream; stream = next) { next = TAILQ_NEXT(stream, next_service_stream); if (stream->stream_flags & STREAM_CALL_ONCLOSE) lsquic_stream_call_on_close(stream); if (stream->stream_flags & STREAM_FREE_STREAM) { n_our_destroyed += is_our_stream(conn, stream); TAILQ_REMOVE(&conn->fc_pub.service_streams, stream, next_service_stream); el = lsquic_hash_find(conn->fc_streams, &stream->id, sizeof(stream->id)); if (el) lsquic_hash_erase(conn->fc_streams, el); conn_mark_stream_closed(conn, stream->id); SAVE_STREAM_HISTORY(conn, stream); lsquic_stream_destroy(stream); } } if (either_side_going_away(conn)) while (conn->fc_n_delayed_streams) { --conn->fc_n_delayed_streams; LSQ_DEBUG("goaway mode: delayed stream results in null ctor"); (void) conn->fc_stream_ifs[STREAM_IF_STD].stream_if->on_new_stream( conn->fc_stream_ifs[STREAM_IF_STD].stream_if_ctx, NULL); } else while (n_our_destroyed && conn->fc_n_delayed_streams) { --n_our_destroyed; --conn->fc_n_delayed_streams; LSQ_DEBUG("creating delayed stream"); if (!new_stream(conn, generate_stream_id(conn))) { ABORT_ERROR("%s: cannot create new stream: %s", __func__, strerror(errno)); break; } assert(count_streams(conn, 0) <= conn->fc_cfg.max_streams_out); } } struct filter_stream_ctx { struct full_conn *conn; uint32_t last_stream_id, max_peer_stream_id; }; static int filter_out_old_streams (void *ctx, lsquic_stream_t *stream) { struct filter_stream_ctx *const fctx = ctx; return ((!((stream->id ^ fctx->last_stream_id) & 1) && stream->id > fctx->last_stream_id) || (!((stream->id ^ fctx->max_peer_stream_id) & 1) && stream->id > fctx->max_peer_stream_id)); } static int dispatch_stream_rw_events (struct full_conn *conn, lsquic_stream_t *stream) { struct stream_rw_prog_status saved_status; int is_reset, progress_made; is_reset = lsquic_stream_is_reset(stream); lsquic_stream_get_rw_prog_status(stream, &saved_status); lsquic_stream_dispatch_rw_events(stream); progress_made = lsquic_stream_progress_was_made(stream, &saved_status); if (!is_reset && lsquic_stream_is_reset(stream)) lsquic_send_ctl_reset_stream(&conn->fc_send_ctl, stream->id); return progress_made; } /* Return 1 if progress was made, 0 otherwise */ static int process_streams_rw_events (struct full_conn *conn) { lsquic_stream_t *stream; struct filter_stream_ctx fctx; struct stream_prio_iter spi; int progress_count; if (TAILQ_EMPTY(&conn->fc_pub.rw_streams)) return 0; progress_count = 0; fctx.last_stream_id = conn->fc_last_stream_id; fctx.max_peer_stream_id = conn->fc_max_peer_stream_id; lsquic_spi_init(&spi, TAILQ_FIRST(&conn->fc_pub.rw_streams), TAILQ_LAST(&conn->fc_pub.rw_streams, lsquic_streams_tailq), (uintptr_t) &TAILQ_NEXT((lsquic_stream_t *) NULL, next_rw_stream), STREAM_RW_EVENT_FLAGS, conn->fc_conn.cn_cid, "rw-1"); for (stream = lsquic_spi_first(&spi); stream; stream = lsquic_spi_next(&spi)) progress_count += dispatch_stream_rw_events(conn, stream); /* If new streams were created as result of the RW dispatching above, * process these new streams. */ if (fctx.last_stream_id < conn->fc_last_stream_id || fctx.max_peer_stream_id < conn->fc_max_peer_stream_id) { fctx.conn = conn; lsquic_spi_init_ext(&spi, TAILQ_FIRST(&conn->fc_pub.rw_streams), TAILQ_LAST(&conn->fc_pub.rw_streams, lsquic_streams_tailq), (uintptr_t) &TAILQ_NEXT((lsquic_stream_t *) NULL, next_rw_stream), STREAM_RW_EVENT_FLAGS, filter_out_old_streams, &fctx, conn->fc_conn.cn_cid, "rw-2"); for (stream = lsquic_spi_first(&spi); stream; stream = lsquic_spi_next(&spi)) progress_count += dispatch_stream_rw_events(conn, stream); } return progress_count > 0; } /* Return 1 if progress was made, 0 otherwise. */ static int process_hsk_stream_rw_events (struct full_conn *conn) { lsquic_stream_t *stream; TAILQ_FOREACH(stream, &conn->fc_pub.rw_streams, next_rw_stream) if (LSQUIC_STREAM_HANDSHAKE == stream->id) return dispatch_stream_rw_events(conn, stream); return 0; } #if 1 # define verify_ack_frame(a, b, c) #else static void verify_ack_frame (struct full_conn *conn, const unsigned char *buf, int bufsz) { unsigned i; int parsed_len; struct ack_info *ack_info; const struct lsquic_packno_range *range; char ack_buf[512]; unsigned buf_off = 0; int nw; ack_info = conn->fc_pub.mm->acki; parsed_len = parse_ack_frame(buf, bufsz, ack_info); assert(parsed_len == bufsz); for (range = lsquic_rechist_first(&conn->fc_rechist), i = 0; range; range = lsquic_rechist_next(&conn->fc_rechist), ++i) { assert(i < ack_info->n_ranges); assert(range->high == ack_info->ranges[i].high); assert(range->low == ack_info->ranges[i].low); if (LSQ_LOG_ENABLED(LSQ_LOG_DEBUG)) { nw = snprintf(ack_buf + buf_off, sizeof(ack_buf) - buf_off, "[%"PRIu64"-%"PRIu64"]", range->high, range->low); assert(nw >= 0); buf_off += nw; } } assert(i == ack_info->n_ranges); LSQ_DEBUG("Sent ACK frame %s", ack_buf); } #endif static void generate_ack_frame (struct full_conn *conn) { lsquic_packet_out_t *packet_out; lsquic_time_t now; int has_missing, w; packet_out = lsquic_send_ctl_new_packet_out(&conn->fc_send_ctl, 0); if (!packet_out) { ABORT_ERROR("cannot allocate packet: %s", strerror(errno)); return; } lsquic_send_ctl_scheduled_one(&conn->fc_send_ctl, packet_out); now = lsquic_time_now(); w = conn->fc_conn.cn_pf->pf_gen_ack_frame( packet_out->po_data + packet_out->po_data_sz, lsquic_packet_out_avail(packet_out), (gaf_rechist_first_f) lsquic_rechist_first, (gaf_rechist_next_f) lsquic_rechist_next, (gaf_rechist_largest_recv_f) lsquic_rechist_largest_recv, &conn->fc_rechist, now, &has_missing); if (w < 0) { ABORT_ERROR("generating ACK frame failed: %d", errno); return; } EV_LOG_GENERATED_ACK_FRAME(LSQUIC_LOG_CONN_ID, conn->fc_conn.cn_pf, packet_out->po_data + packet_out->po_data_sz, w); verify_ack_frame(conn, packet_out->po_data + packet_out->po_data_sz, w); lsquic_send_ctl_scheduled_ack(&conn->fc_send_ctl); packet_out->po_frame_types |= 1 << QUIC_FRAME_ACK; packet_out->po_data_sz += w; packet_out->po_regen_sz += w; if (has_missing) conn->fc_flags |= FC_ACK_HAD_MISS; else conn->fc_flags &= ~FC_ACK_HAD_MISS; LSQ_DEBUG("Put %d bytes of ACK frame into packet on outgoing queue", w); if (conn->fc_conn.cn_version >= LSQVER_039 && conn->fc_n_cons_unretx >= 20 && !lsquic_send_ctl_have_outgoing_retx_frames(&conn->fc_send_ctl)) { LSQ_DEBUG("schedule WINDOW_UPDATE frame after %u non-retx " "packets sent", conn->fc_n_cons_unretx); conn->fc_flags |= FC_SEND_WUF; } } static int conn_ok_to_close (const struct full_conn *conn) { assert(conn->fc_flags & FC_CLOSING); return !(conn->fc_flags & FC_SERVER) || (conn->fc_flags & FC_RECV_CLOSE) || ( !lsquic_send_ctl_have_outgoing_stream_frames(&conn->fc_send_ctl) && lsquic_hash_count(conn->fc_streams) == 0 && lsquic_send_ctl_have_unacked_stream_frames(&conn->fc_send_ctl) == 0); } static enum tick_st immediate_close (struct full_conn *conn) { lsquic_packet_out_t *packet_out; const char *error_reason; unsigned error_code; int sz; if (conn->fc_flags & (FC_TICK_CLOSE|FC_GOT_PRST)) return TICK_CLOSE; conn->fc_flags |= FC_TICK_CLOSE; /* No reason to send anything that's been scheduled if connection is * being closed immedately. This also ensures that packet numbers * sequence is always increasing. */ lsquic_send_ctl_drop_scheduled(&conn->fc_send_ctl); if ((conn->fc_flags & FC_TIMED_OUT) && conn->fc_settings->es_silent_close) return TICK_CLOSE; packet_out = lsquic_send_ctl_new_packet_out(&conn->fc_send_ctl, 0); if (!packet_out) { LSQ_WARN("cannot allocate packet: %s", strerror(errno)); return TICK_CLOSE; } assert(conn->fc_flags & (FC_ERROR|FC_ABORTED|FC_TIMED_OUT)); if (conn->fc_flags & FC_ERROR) { error_code = 0x01; /* QUIC_INTERNAL_ERROR */ error_reason = "connection error"; } else if (conn->fc_flags & FC_ABORTED) { error_code = 0x10; /* QUIC_PEER_GOING_AWAY */ error_reason = "user aborted connection"; } else if (conn->fc_flags & FC_TIMED_OUT) { error_code = 0x19; /* QUIC_NETWORK_IDLE_TIMEOUT */ error_reason = "connection timed out"; } else { error_code = 0x10; /* QUIC_PEER_GOING_AWAY */ error_reason = NULL; } lsquic_send_ctl_scheduled_one(&conn->fc_send_ctl, packet_out); sz = conn->fc_conn.cn_pf->pf_gen_connect_close_frame( packet_out->po_data + packet_out->po_data_sz, lsquic_packet_out_avail(packet_out), error_code, error_reason, error_reason ? strlen(error_reason) : 0); if (sz < 0) { LSQ_WARN("%s failed", __func__); return TICK_CLOSE; } packet_out->po_data_sz += sz; packet_out->po_frame_types |= 1 << QUIC_FRAME_CONNECTION_CLOSE; LSQ_DEBUG("generated CONNECTION_CLOSE frame in its own packet"); return TICK_SEND|TICK_CLOSE; } static enum tick_st full_conn_ci_tick (lsquic_conn_t *lconn, lsquic_time_t now) { struct full_conn *conn = (struct full_conn *) lconn; lsquic_packet_out_t *last_packet_out; int have_delayed_packets; unsigned n; int progress_made; enum tick_st progress_tick = 0; #define CLOSE_IF_NECESSARY() do { \ if (conn->fc_flags & FC_IMMEDIATE_CLOSE_FLAGS) \ return progress_tick | immediate_close(conn); \ } while (0) #define RETURN_IF_OUT_OF_PACKETS() do { \ if (!lsquic_send_ctl_can_send(&conn->fc_send_ctl)) \ { \ if (0 == lsquic_send_ctl_n_scheduled(&conn->fc_send_ctl)) \ { \ LSQ_DEBUG("used up packet allowance, quiet now (line %d)", \ __LINE__); \ return progress_tick | TICK_QUIET; \ } \ else \ { \ LSQ_DEBUG("used up packet allowance, sending now (line %d)",\ __LINE__); \ return progress_tick | TICK_SEND; \ } \ } \ } while (0) assert(!(conn->fc_conn.cn_flags & LSCONN_RW_PENDING)); lsquic_send_ctl_tick(&conn->fc_send_ctl, now); CLOSE_IF_NECESSARY(); if (!(conn->fc_flags & FC_SERVER)) { lsquic_alarmset_unset(&conn->fc_alset, AL_PING); lsquic_send_ctl_sanity_check(&conn->fc_send_ctl); } lsquic_alarmset_ring_expired(&conn->fc_alset, now); CLOSE_IF_NECESSARY(); /* To make things simple, only stream 1 is active until the handshake * has been completed. This will be adjusted in the future: the client * does not want to wait if it has the server information. */ if (conn->fc_conn.cn_flags & LSCONN_HANDSHAKE_DONE) progress_made = process_streams_rw_events(conn); else progress_made = process_hsk_stream_rw_events(conn); progress_tick |= progress_made << TICK_BIT_PROGRESS; CLOSE_IF_NECESSARY(); if (conn->fc_flags & FC_FIRST_TICK) { conn->fc_flags &= ~FC_FIRST_TICK; have_delayed_packets = 0; } else /* If there are any scheduled packets at this point, it means that * they were not sent during previous tick; in other words, they * are delayed. When there are delayed packets, the only packet * we sometimes add is a packet with an ACK frame, and we add it * to the *front* of the queue. */ have_delayed_packets = lsquic_send_ctl_squeeze_sched( &conn->fc_send_ctl); if ((conn->fc_flags & FC_ACK_QUEUED) || lsquic_send_ctl_lost_ack(&conn->fc_send_ctl)) { if (have_delayed_packets) lsquic_send_ctl_reset_packnos(&conn->fc_send_ctl); /* ACK frame generation fails with an error if it does not fit into * a single packet (it always should fit). */ generate_ack_frame(conn); CLOSE_IF_NECESSARY(); reset_ack_state(conn); /* Try to send STOP_WAITING frame at the same time we send an ACK * This follows reference implementation. */ if (!(conn->fc_flags & FC_NSTP)) conn->fc_flags |= FC_SEND_STOP_WAITING; if (have_delayed_packets) { if (conn->fc_flags & FC_SEND_STOP_WAITING) { /* TODO: ensure that STOP_WAITING frame is in the same packet * as the ACK frame in delayed packet mode. */ generate_stop_waiting_frame(conn); CLOSE_IF_NECESSARY(); } lsquic_send_ctl_ack_to_front(&conn->fc_send_ctl); } } if (have_delayed_packets) /* The reason for not adding STOP_WAITING and other frames below * to the packet carrying ACK frame generated when there are delayed * packets is so that if the ACK packet itself is delayed, it can be * dropped and replaced by new ACK packet. This way, we are never * more than 1 packet over CWND. */ return progress_tick | TICK_SEND; RETURN_IF_OUT_OF_PACKETS(); /* Try to fit any of the following three frames -- STOP_WAITING, * WINDOW_UPDATE, and GOAWAY -- before checking if we have run * out of packets. If either of them does not fit, it will be * tried next time around. */ if (conn->fc_flags & FC_SEND_STOP_WAITING) { generate_stop_waiting_frame(conn); CLOSE_IF_NECESSARY(); } if (lsquic_cfcw_fc_offsets_changed(&conn->fc_pub.cfcw) || (conn->fc_flags & FC_SEND_WUF)) { conn->fc_flags |= FC_SEND_WUF; generate_wuf_conn(conn); CLOSE_IF_NECESSARY(); } if (conn->fc_flags & FC_SEND_GOAWAY) { generate_goaway_frame(conn); CLOSE_IF_NECESSARY(); } n = lsquic_send_ctl_reschedule_packets(&conn->fc_send_ctl); if (n > 0) CLOSE_IF_NECESSARY(); RETURN_IF_OUT_OF_PACKETS(); if (conn->fc_conn.cn_flags & LSCONN_SEND_BLOCKED) { if (generate_blocked_frame(conn, 0)) conn->fc_conn.cn_flags &= ~LSCONN_SEND_BLOCKED; else RETURN_IF_OUT_OF_PACKETS(); } if (!TAILQ_EMPTY(&conn->fc_pub.sending_streams)) { progress_made = process_streams_ready_to_send(conn); progress_tick |= progress_made << TICK_BIT_PROGRESS; /* If last packet on the queue contains a stream-related frame, mark it * unwriteable to force a new packet allocation on the next tick. This * is to prevent more than one STREAM or RST_STREAM frame from the same * stream to be written to the same packet. */ last_packet_out = lsquic_send_ctl_last_scheduled(&conn->fc_send_ctl); if (last_packet_out && (last_packet_out->po_frame_types & ((1 << QUIC_FRAME_STREAM)|(1 << QUIC_FRAME_RST_STREAM)))) last_packet_out->po_flags &= ~PO_WRITEABLE; } CLOSE_IF_NECESSARY(); service_streams(conn); RETURN_IF_OUT_OF_PACKETS(); if ((conn->fc_flags & FC_CLOSING) && conn_ok_to_close(conn)) { LSQ_DEBUG("connection is OK to close"); /* This is normal termination sequence. * * Generate CONNECTION_CLOSE frame if we are responding to one, have * packets scheduled to send, or silent close flag is not set. */ conn->fc_flags |= FC_TICK_CLOSE; if ((conn->fc_flags & FC_RECV_CLOSE) || 0 != lsquic_send_ctl_n_scheduled(&conn->fc_send_ctl) || !conn->fc_settings->es_silent_close) { generate_connection_close_packet(conn); return progress_tick | TICK_SEND|TICK_CLOSE; } else return progress_tick | TICK_CLOSE; } if (0 == lsquic_send_ctl_n_scheduled(&conn->fc_send_ctl)) { if (conn->fc_flags & FC_SEND_PING) { conn->fc_flags &= ~FC_SEND_PING; generate_ping_frame(conn); CLOSE_IF_NECESSARY(); assert(lsquic_send_ctl_n_scheduled(&conn->fc_send_ctl) != 0); } else return progress_tick | TICK_QUIET; } else if (!(conn->fc_flags & FC_SERVER)) { lsquic_alarmset_unset(&conn->fc_alset, AL_PING); lsquic_send_ctl_sanity_check(&conn->fc_send_ctl); conn->fc_flags &= ~FC_SEND_PING; /* It may have rung */ } now = lsquic_time_now(); lsquic_alarmset_set(&conn->fc_alset, AL_IDLE, now + conn->fc_settings->es_idle_conn_to); /* From the spec: * " The PING frame should be used to keep a connection alive when * " a stream is open. */ if (0 == (conn->fc_flags & FC_SERVER) && lsquic_hash_count(conn->fc_streams) > 0) lsquic_alarmset_set(&conn->fc_alset, AL_PING, now + TIME_BETWEEN_PINGS); return progress_tick | TICK_SEND; } static void full_conn_ci_packet_in (lsquic_conn_t *lconn, lsquic_packet_in_t *packet_in) { struct full_conn *conn = (struct full_conn *) lconn; lsquic_alarmset_set(&conn->fc_alset, AL_IDLE, packet_in->pi_received + conn->fc_settings->es_idle_conn_to); if (0 == (conn->fc_flags & FC_ERROR)) if (0 != process_incoming_packet(conn, packet_in)) conn->fc_flags |= FC_ERROR; } static lsquic_packet_out_t * full_conn_ci_next_packet_to_send (lsquic_conn_t *lconn) { struct full_conn *conn = (struct full_conn *) lconn; return lsquic_send_ctl_next_packet_to_send(&conn->fc_send_ctl); } static void full_conn_ci_packet_sent (lsquic_conn_t *lconn, lsquic_packet_out_t *packet_out) { struct full_conn *conn = (struct full_conn *) lconn; int s; if (packet_out->po_frame_types & QFRAME_RETRANSMITTABLE_MASK) { conn->fc_n_cons_unretx = 0; lsquic_alarmset_set(&conn->fc_alset, AL_IDLE, packet_out->po_sent + conn->fc_settings->es_idle_conn_to); } else ++conn->fc_n_cons_unretx; s = lsquic_send_ctl_sent_packet(&conn->fc_send_ctl, packet_out); if (s != 0) ABORT_ERROR("sent packet failed: %s", strerror(errno)); #if FULL_CONN_STATS ++conn->fc_stats.n_packets_out; #endif } static void full_conn_ci_packet_not_sent (lsquic_conn_t *lconn, lsquic_packet_out_t *packet_out) { struct full_conn *conn = (struct full_conn *) lconn; lsquic_send_ctl_delayed_one(&conn->fc_send_ctl, packet_out); } static void full_conn_ci_handshake_done (lsquic_conn_t *lconn) { struct full_conn *conn = (struct full_conn *) lconn; LSQ_DEBUG("handshake reportedly done"); lsquic_alarmset_unset(&conn->fc_alset, AL_HANDSHAKE); if (0 == apply_peer_settings(conn)) lconn->cn_flags |= LSCONN_HANDSHAKE_DONE; else conn->fc_flags |= FC_ERROR; } static int full_conn_ci_user_wants_read (lsquic_conn_t *lconn) { struct full_conn *conn = (struct full_conn *) lconn; const lsquic_stream_t *stream; TAILQ_FOREACH(stream, &conn->fc_pub.rw_streams, next_rw_stream) if (stream->stream_flags & STREAM_WANT_READ) return 1; return 0; } void lsquic_conn_abort (lsquic_conn_t *lconn) { struct full_conn *conn = (struct full_conn *) lconn; LSQ_INFO("User aborted connection"); conn->fc_flags |= FC_ABORTED; } void full_conn_close_internal (lsquic_conn_t *lconn, int is_user) { struct full_conn *conn = (struct full_conn *) lconn; lsquic_stream_t *stream; struct lsquic_hash_elem *el; if (!(conn->fc_flags & FC_CLOSING)) { if (is_user) LSQ_INFO("User closed connection"); for (el = lsquic_hash_first(conn->fc_streams); el; el = lsquic_hash_next(conn->fc_streams)) { stream = lsquic_hashelem_getdata(el); lsquic_stream_shutdown_internal(stream); } conn->fc_flags |= FC_CLOSING; if (!(conn->fc_flags & FC_GOAWAY_SENT)) conn->fc_flags |= FC_SEND_GOAWAY; } } void lsquic_conn_close (lsquic_conn_t *lconn) { full_conn_close_internal(lconn, 1); } void lsquic_conn_going_away (lsquic_conn_t *lconn) { struct full_conn *conn = (struct full_conn *) lconn; if (!(conn->fc_flags & (FC_CLOSING|FC_GOING_AWAY))) { LSQ_INFO("connection marked as going away"); assert(!(conn->fc_flags & FC_SEND_GOAWAY)); conn->fc_flags |= FC_GOING_AWAY; if (!(conn->fc_flags & FC_GOAWAY_SENT)) conn->fc_flags |= FC_SEND_GOAWAY; } } /* Find stream when stream ID is read in from HEADERS stream. If stream * cannot be found or created, the connection is aborted. */ #if __GNUC__ __attribute__((nonnull(3))) #endif static lsquic_stream_t * find_stream_on_headers (struct full_conn *conn, uint32_t stream_id, const char *what) { lsquic_stream_t *stream = find_stream_by_id(conn, stream_id); if (!stream) { if (conn_is_stream_closed(conn, stream_id)) { LSQ_DEBUG("drop incoming %s for closed stream %u", what, stream_id); return NULL; } if (is_peer_initiated(conn, stream_id)) { unsigned in_count = count_streams(conn, 1); LSQ_DEBUG("number of peer-initiated streams: %u", in_count); if (in_count >= conn->fc_cfg.max_streams_in) { ABORT_ERROR("incoming %s for stream %u would exceed " "limit: %u", what, stream_id, conn->fc_cfg.max_streams_in); return NULL; } if ((conn->fc_flags & FC_GOING_AWAY) && stream_id > conn->fc_max_peer_stream_id) { LSQ_DEBUG("going away: drop headers for new stream %u", stream_id); return NULL; } } else { ABORT_ERROR("frame for never-initiated stream (push promise?)"); return NULL; } stream = new_stream(conn, stream_id); if (!stream) { ABORT_ERROR("cannot create new stream: %s", strerror(errno)); return NULL; } if (stream_id > conn->fc_max_peer_stream_id) conn->fc_max_peer_stream_id = stream_id; } return stream; } static void headers_stream_on_conn_error (void *ctx) { struct full_conn *conn = ctx; ABORT_ERROR("connection error reported by HEADERS stream"); } static void headers_stream_on_stream_error (void *ctx, uint32_t stream_id) { struct full_conn *conn = ctx; lsquic_stream_t *stream = find_stream_on_headers(conn, stream_id, "error"); if (stream) { LSQ_DEBUG("resetting stream %u due to error", stream_id); /* We use code 1, which is QUIC_INTERNAL_ERROR (see * [draft-hamilton-quic-transport-protocol-01], Section 10), for all * errors. There does not seem to be a good reason to figure out * and send more specific error codes. */ lsquic_stream_reset_ext(stream, 1, 0); } } static void headers_stream_on_enable_push (void *ctx, int enable_push) { struct full_conn *conn = ctx; if (0 == enable_push) { LSQ_DEBUG("server push %d -> 0", !!(conn->fc_flags & FC_SUPPORT_PUSH)); conn->fc_flags &= ~FC_SUPPORT_PUSH; } else if (conn->fc_settings->es_support_push) { LSQ_DEBUG("server push %d -> 1", !!(conn->fc_flags & FC_SUPPORT_PUSH)); conn->fc_flags |= FC_SUPPORT_PUSH; } else LSQ_INFO("not enabling server push that's disabled in engine settings"); } static void headers_stream_on_incoming_headers (void *ctx, struct uncompressed_headers *uh) { struct full_conn *conn = ctx; lsquic_stream_t *stream; LSQ_DEBUG("incoming headers for stream %u", uh->uh_stream_id); stream = find_stream_on_headers(conn, uh->uh_stream_id, "headers"); if (!stream) { free(uh); return; } if (0 != lsquic_stream_uh_in(stream, uh)) { ABORT_ERROR("stream %u refused incoming headers", uh->uh_stream_id); free(uh); } } static void headers_stream_on_push_promise (void *ctx, struct uncompressed_headers *uh) { struct full_conn *conn = ctx; lsquic_stream_t *stream; assert(!(conn->fc_flags & FC_SERVER)); LSQ_DEBUG("push promise for stream %u in response to %u", uh->uh_oth_stream_id, uh->uh_stream_id); if (0 == (uh->uh_stream_id & 1) || 0 != (uh->uh_oth_stream_id & 1)) { ABORT_ERROR("invalid push promise stream IDs: %u, %u", uh->uh_oth_stream_id, uh->uh_stream_id); free(uh); return; } if (!(conn_is_stream_closed(conn, uh->uh_stream_id) || find_stream_by_id(conn, uh->uh_stream_id))) { ABORT_ERROR("invalid push promise original stream ID %u never " "initiated", uh->uh_stream_id); free(uh); return; } if (conn_is_stream_closed(conn, uh->uh_oth_stream_id) || find_stream_by_id(conn, uh->uh_oth_stream_id)) { ABORT_ERROR("invalid promised stream ID %u already used", uh->uh_oth_stream_id); free(uh); return; } stream = new_stream_ext(conn, uh->uh_oth_stream_id, STREAM_IF_STD, SCF_DI_AUTOSWITCH|(conn->fc_enpub->enp_settings.es_rw_once ? SCF_DISP_RW_ONCE : 0)); if (!stream) { ABORT_ERROR("cannot create stream: %s", strerror(errno)); free(uh); return; } lsquic_stream_push_req(stream, uh); lsquic_stream_call_on_new(stream, conn->fc_stream_ifs[STREAM_IF_STD].stream_if_ctx); return; } static void headers_stream_on_priority (void *ctx, uint32_t stream_id, int exclusive, uint32_t dep_stream_id, unsigned weight) { struct full_conn *conn = ctx; lsquic_stream_t *stream; LSQ_DEBUG("got priority frame for stream %u: (ex: %d; dep stream: %u; " "weight: %u)", stream_id, exclusive, dep_stream_id, weight); stream = find_stream_on_headers(conn, stream_id, "priority"); if (stream) lsquic_stream_set_priority_internal(stream, weight); } int lsquic_conn_is_push_enabled(lsquic_conn_t *c) { return ((struct full_conn *)c)->fc_flags & FC_SUPPORT_PUSH; } lsquic_conn_ctx_t * lsquic_conn_get_ctx (const lsquic_conn_t *lconn) { struct full_conn *const conn = (struct full_conn *) lconn; return conn->fc_conn_ctx; } static const struct headers_stream_callbacks headers_callbacks = { .hsc_on_headers = headers_stream_on_incoming_headers, .hsc_on_push_promise = headers_stream_on_push_promise, .hsc_on_priority = headers_stream_on_priority, .hsc_on_stream_error = headers_stream_on_stream_error, .hsc_on_conn_error = headers_stream_on_conn_error, .hsc_on_enable_push = headers_stream_on_enable_push, }; static const struct conn_iface full_conn_iface = { .ci_destroy = full_conn_ci_destroy, .ci_handshake_done = full_conn_ci_handshake_done, .ci_next_packet_to_send = full_conn_ci_next_packet_to_send, .ci_packet_in = full_conn_ci_packet_in, .ci_packet_not_sent = full_conn_ci_packet_not_sent, .ci_packet_sent = full_conn_ci_packet_sent, .ci_tick = full_conn_ci_tick, .ci_user_wants_read = full_conn_ci_user_wants_read, };