/* * Copyright 2022 The OpenSSL Project Authors. All Rights Reserved. * * Licensed under the Apache License 2.0 (the "License"). You may not use * this file except in compliance with the License. You can obtain a copy * in the file LICENSE in the source distribution or at * https://www.openssl.org/source/license.html */ #include "internal/quic_channel.h" #include "internal/quic_error.h" #include "internal/quic_rx_depack.h" #include "../ssl_local.h" #include "quic_channel_local.h" #include /* * NOTE: While this channel implementation currently has basic server support, * this functionality has been implemented for internal testing purposes and is * not suitable for network use. In particular, it does not implement address * validation, anti-amplification or retry logic. * * TODO(QUIC): Implement address validation and anti-amplification * TODO(QUIC): Implement retry logic */ #define INIT_DCID_LEN 8 #define INIT_CRYPTO_BUF_LEN 8192 #define INIT_APP_BUF_LEN 8192 /* * Interval before we force a PING to ensure NATs don't timeout. This is based * on the lowest commonly seen value of 30 seconds as cited in RFC 9000 s. * 10.1.2. */ #define MAX_NAT_INTERVAL (ossl_ms2time(25000)) static void ch_rx_pre(QUIC_CHANNEL *ch); static int ch_rx(QUIC_CHANNEL *ch); static int ch_tx(QUIC_CHANNEL *ch); static void ch_tick(QUIC_TICK_RESULT *res, void *arg, uint32_t flags); static void ch_rx_handle_packet(QUIC_CHANNEL *ch); static OSSL_TIME ch_determine_next_tick_deadline(QUIC_CHANNEL *ch); static int ch_retry(QUIC_CHANNEL *ch, const unsigned char *retry_token, size_t retry_token_len, const QUIC_CONN_ID *retry_scid); static void ch_cleanup(QUIC_CHANNEL *ch); static int ch_generate_transport_params(QUIC_CHANNEL *ch); static int ch_on_transport_params(const unsigned char *params, size_t params_len, void *arg); static int ch_on_handshake_alert(void *arg, unsigned char alert_code); static int ch_on_handshake_complete(void *arg); static int ch_on_handshake_yield_secret(uint32_t enc_level, int direction, uint32_t suite_id, EVP_MD *md, const unsigned char *secret, size_t secret_len, void *arg); static int ch_on_crypto_recv_record(const unsigned char **buf, size_t *bytes_read, void *arg); static int ch_on_crypto_release_record(size_t bytes_read, void *arg); static int crypto_ensure_empty(QUIC_RSTREAM *rstream); static int ch_on_crypto_send(const unsigned char *buf, size_t buf_len, size_t *consumed, void *arg); static OSSL_TIME get_time(void *arg); static uint64_t get_stream_limit(int uni, void *arg); static int rx_early_validate(QUIC_PN pn, int pn_space, void *arg); static int ch_retry(QUIC_CHANNEL *ch, const unsigned char *retry_token, size_t retry_token_len, const QUIC_CONN_ID *retry_scid); static void ch_update_idle(QUIC_CHANNEL *ch); static int ch_discard_el(QUIC_CHANNEL *ch, uint32_t enc_level); static void ch_on_idle_timeout(QUIC_CHANNEL *ch); static void ch_update_idle(QUIC_CHANNEL *ch); static void ch_update_ping_deadline(QUIC_CHANNEL *ch); static void ch_raise_net_error(QUIC_CHANNEL *ch); static void ch_on_terminating_timeout(QUIC_CHANNEL *ch); static void ch_start_terminating(QUIC_CHANNEL *ch, const QUIC_TERMINATE_CAUSE *tcause, int force_immediate); static void ch_default_packet_handler(QUIC_URXE *e, void *arg); static int ch_server_on_new_conn(QUIC_CHANNEL *ch, const BIO_ADDR *peer, const QUIC_CONN_ID *peer_scid, const QUIC_CONN_ID *peer_dcid); static int gen_rand_conn_id(OSSL_LIB_CTX *libctx, size_t len, QUIC_CONN_ID *cid) { if (len > QUIC_MAX_CONN_ID_LEN) return 0; cid->id_len = (unsigned char)len; if (RAND_bytes_ex(libctx, cid->id, len, len * 8) != 1) { cid->id_len = 0; return 0; } return 1; } /* * QUIC Channel Initialization and Teardown * ======================================== */ static int ch_init(QUIC_CHANNEL *ch) { OSSL_QUIC_TX_PACKETISER_ARGS txp_args = {0}; OSSL_QTX_ARGS qtx_args = {0}; OSSL_QRX_ARGS qrx_args = {0}; QUIC_TLS_ARGS tls_args = {0}; uint32_t pn_space; size_t rx_short_cid_len = ch->is_server ? INIT_DCID_LEN : 0; /* For clients, generate our initial DCID. */ if (!ch->is_server && !gen_rand_conn_id(ch->libctx, INIT_DCID_LEN, &ch->init_dcid)) goto err; /* We plug in a network write BIO to the QTX later when we get one. */ qtx_args.libctx = ch->libctx; qtx_args.mdpl = QUIC_MIN_INITIAL_DGRAM_LEN; ch->rx_max_udp_payload_size = qtx_args.mdpl; ch->qtx = ossl_qtx_new(&qtx_args); if (ch->qtx == NULL) goto err; ch->txpim = ossl_quic_txpim_new(); if (ch->txpim == NULL) goto err; ch->cfq = ossl_quic_cfq_new(); if (ch->cfq == NULL) goto err; if (!ossl_quic_txfc_init(&ch->conn_txfc, NULL)) goto err; if (!ossl_quic_rxfc_init(&ch->conn_rxfc, NULL, 2 * 1024 * 1024, 10 * 1024 * 1024, get_time, ch)) goto err; if (!ossl_statm_init(&ch->statm)) goto err; ch->have_statm = 1; ch->cc_method = &ossl_cc_dummy_method; if ((ch->cc_data = ch->cc_method->new(NULL, NULL, NULL)) == NULL) goto err; if ((ch->ackm = ossl_ackm_new(get_time, ch, &ch->statm, ch->cc_method, ch->cc_data)) == NULL) goto err; if (!ossl_quic_stream_map_init(&ch->qsm, get_stream_limit, ch)) goto err; ch->have_qsm = 1; /* We use a zero-length SCID. */ txp_args.cur_dcid = ch->init_dcid; txp_args.ack_delay_exponent = 3; txp_args.qtx = ch->qtx; txp_args.txpim = ch->txpim; txp_args.cfq = ch->cfq; txp_args.ackm = ch->ackm; txp_args.qsm = &ch->qsm; txp_args.conn_txfc = &ch->conn_txfc; txp_args.conn_rxfc = &ch->conn_rxfc; txp_args.cc_method = ch->cc_method; txp_args.cc_data = ch->cc_data; txp_args.now = get_time; txp_args.now_arg = ch; for (pn_space = QUIC_PN_SPACE_INITIAL; pn_space < QUIC_PN_SPACE_NUM; ++pn_space) { ch->crypto_send[pn_space] = ossl_quic_sstream_new(INIT_CRYPTO_BUF_LEN); if (ch->crypto_send[pn_space] == NULL) goto err; txp_args.crypto[pn_space] = ch->crypto_send[pn_space]; } ch->txp = ossl_quic_tx_packetiser_new(&txp_args); if (ch->txp == NULL) goto err; if ((ch->demux = ossl_quic_demux_new(/*BIO=*/NULL, /*Short CID Len=*/rx_short_cid_len, get_time, ch)) == NULL) goto err; /* * If we are a server, setup our handler for packets not corresponding to * any known DCID on our end. This is for handling clients establishing new * connections. */ if (ch->is_server) ossl_quic_demux_set_default_handler(ch->demux, ch_default_packet_handler, ch); qrx_args.libctx = ch->libctx; qrx_args.demux = ch->demux; qrx_args.short_conn_id_len = rx_short_cid_len; qrx_args.max_deferred = 32; if ((ch->qrx = ossl_qrx_new(&qrx_args)) == NULL) goto err; if (!ossl_qrx_set_early_validation_cb(ch->qrx, rx_early_validate, ch)) goto err; if (!ch->is_server && !ossl_qrx_add_dst_conn_id(ch->qrx, &txp_args.cur_scid)) goto err; for (pn_space = QUIC_PN_SPACE_INITIAL; pn_space < QUIC_PN_SPACE_NUM; ++pn_space) { ch->crypto_recv[pn_space] = ossl_quic_rstream_new(NULL, NULL, 0); if (ch->crypto_recv[pn_space] == NULL) goto err; } if ((ch->stream0 = ossl_quic_stream_map_alloc(&ch->qsm, 0, QUIC_STREAM_INITIATOR_CLIENT | QUIC_STREAM_DIR_BIDI)) == NULL) goto err; if ((ch->stream0->sstream = ossl_quic_sstream_new(INIT_APP_BUF_LEN)) == NULL) goto err; if ((ch->stream0->rstream = ossl_quic_rstream_new(NULL, NULL, 0)) == NULL) goto err; if (!ossl_quic_txfc_init(&ch->stream0->txfc, &ch->conn_txfc)) goto err; if (!ossl_quic_rxfc_init(&ch->stream0->rxfc, &ch->conn_rxfc, 1 * 1024 * 1024, 5 * 1024 * 1024, get_time, ch)) goto err; /* Plug in the TLS handshake layer. */ tls_args.s = ch->tls; tls_args.crypto_send_cb = ch_on_crypto_send; tls_args.crypto_send_cb_arg = ch; tls_args.crypto_recv_rcd_cb = ch_on_crypto_recv_record; tls_args.crypto_recv_rcd_cb_arg = ch; tls_args.crypto_release_rcd_cb = ch_on_crypto_release_record; tls_args.crypto_release_rcd_cb_arg = ch; tls_args.yield_secret_cb = ch_on_handshake_yield_secret; tls_args.yield_secret_cb_arg = ch; tls_args.got_transport_params_cb = ch_on_transport_params; tls_args.got_transport_params_cb_arg= ch; tls_args.handshake_complete_cb = ch_on_handshake_complete; tls_args.handshake_complete_cb_arg = ch; tls_args.alert_cb = ch_on_handshake_alert; tls_args.alert_cb_arg = ch; tls_args.is_server = ch->is_server; if ((ch->qtls = ossl_quic_tls_new(&tls_args)) == NULL) goto err; ch->rx_max_ack_delay = QUIC_DEFAULT_MAX_ACK_DELAY; ch->rx_ack_delay_exp = QUIC_DEFAULT_ACK_DELAY_EXP; ch->rx_active_conn_id_limit = QUIC_MIN_ACTIVE_CONN_ID_LIMIT; ch->max_idle_timeout = QUIC_DEFAULT_IDLE_TIMEOUT; ch->tx_enc_level = QUIC_ENC_LEVEL_INITIAL; ch->rx_enc_level = QUIC_ENC_LEVEL_INITIAL; /* * Determine the QUIC Transport Parameters and serialize the transport * parameters block. (For servers, we do this later as we must defer * generation until we have received the client's transport parameters.) */ if (!ch->is_server && !ch_generate_transport_params(ch)) goto err; ch_update_idle(ch); ossl_quic_reactor_init(&ch->rtor, ch_tick, ch, ch_determine_next_tick_deadline(ch)); return 1; err: ch_cleanup(ch); return 0; } static void ch_cleanup(QUIC_CHANNEL *ch) { uint32_t pn_space; if (ch->ackm != NULL) for (pn_space = QUIC_PN_SPACE_INITIAL; pn_space < QUIC_PN_SPACE_NUM; ++pn_space) ossl_ackm_on_pkt_space_discarded(ch->ackm, pn_space); ossl_quic_tx_packetiser_free(ch->txp); ossl_quic_txpim_free(ch->txpim); ossl_quic_cfq_free(ch->cfq); ossl_qtx_free(ch->qtx); if (ch->cc_data != NULL) ch->cc_method->free(ch->cc_data); if (ch->have_statm) ossl_statm_destroy(&ch->statm); ossl_ackm_free(ch->ackm); if (ch->stream0 != NULL) { assert(ch->have_qsm); ossl_quic_stream_map_release(&ch->qsm, ch->stream0); /* frees sstream */ } if (ch->have_qsm) ossl_quic_stream_map_cleanup(&ch->qsm); for (pn_space = QUIC_PN_SPACE_INITIAL; pn_space < QUIC_PN_SPACE_NUM; ++pn_space) { ossl_quic_sstream_free(ch->crypto_send[pn_space]); ossl_quic_rstream_free(ch->crypto_recv[pn_space]); } ossl_qrx_pkt_release(ch->qrx_pkt); ch->qrx_pkt = NULL; ossl_quic_tls_free(ch->qtls); ossl_qrx_free(ch->qrx); ossl_quic_demux_free(ch->demux); OPENSSL_free(ch->local_transport_params); } QUIC_CHANNEL *ossl_quic_channel_new(const QUIC_CHANNEL_ARGS *args) { QUIC_CHANNEL *ch = NULL; if ((ch = OPENSSL_zalloc(sizeof(*ch))) == NULL) return NULL; ch->libctx = args->libctx; ch->propq = args->propq; ch->is_server = args->is_server; ch->tls = args->tls; ch->mutex = args->mutex; ch->now_cb = args->now_cb; ch->now_cb_arg = args->now_cb_arg; if (!ch_init(ch)) { OPENSSL_free(ch); return NULL; } return ch; } void ossl_quic_channel_free(QUIC_CHANNEL *ch) { if (ch == NULL) return; ch_cleanup(ch); OPENSSL_free(ch); } /* Set mutator callbacks for test framework support */ int ossl_quic_channel_set_mutator(QUIC_CHANNEL *ch, ossl_mutate_packet_cb mutatecb, ossl_finish_mutate_cb finishmutatecb, void *mutatearg) { if (ch->qtx == NULL) return 0; ossl_qtx_set_mutator(ch->qtx, mutatecb, finishmutatecb, mutatearg); return 1; } int ossl_quic_channel_get_peer_addr(QUIC_CHANNEL *ch, BIO_ADDR *peer_addr) { *peer_addr = ch->cur_peer_addr; return 1; } int ossl_quic_channel_set_peer_addr(QUIC_CHANNEL *ch, const BIO_ADDR *peer_addr) { ch->cur_peer_addr = *peer_addr; return 1; } QUIC_REACTOR *ossl_quic_channel_get_reactor(QUIC_CHANNEL *ch) { return &ch->rtor; } QUIC_STREAM_MAP *ossl_quic_channel_get_qsm(QUIC_CHANNEL *ch) { return &ch->qsm; } OSSL_STATM *ossl_quic_channel_get_statm(QUIC_CHANNEL *ch) { return &ch->statm; } QUIC_STREAM *ossl_quic_channel_get_stream_by_id(QUIC_CHANNEL *ch, uint64_t stream_id) { return ossl_quic_stream_map_get_by_id(&ch->qsm, stream_id); } int ossl_quic_channel_is_active(const QUIC_CHANNEL *ch) { return ch != NULL && ch->state == QUIC_CHANNEL_STATE_ACTIVE; } int ossl_quic_channel_is_terminating(const QUIC_CHANNEL *ch) { if (ch->state == QUIC_CHANNEL_STATE_TERMINATING_CLOSING || ch->state == QUIC_CHANNEL_STATE_TERMINATING_DRAINING) return 1; return 0; } int ossl_quic_channel_is_terminated(const QUIC_CHANNEL *ch) { if (ch->state == QUIC_CHANNEL_STATE_TERMINATED) return 1; return 0; } int ossl_quic_channel_is_term_any(const QUIC_CHANNEL *ch) { return ossl_quic_channel_is_terminating(ch) || ossl_quic_channel_is_terminated(ch); } QUIC_TERMINATE_CAUSE ossl_quic_channel_get_terminate_cause(const QUIC_CHANNEL *ch) { return ch->terminate_cause; } int ossl_quic_channel_is_handshake_complete(const QUIC_CHANNEL *ch) { return ch->handshake_complete; } int ossl_quic_channel_is_handshake_confirmed(const QUIC_CHANNEL *ch) { return ch->handshake_confirmed; } QUIC_DEMUX *ossl_quic_channel_get0_demux(QUIC_CHANNEL *ch) { return ch->demux; } CRYPTO_MUTEX *ossl_quic_channel_get_mutex(QUIC_CHANNEL *ch) { return ch->mutex; } /* * QUIC Channel: Callbacks from Miscellaneous Subsidiary Components * ================================================================ */ /* Used by various components. */ static OSSL_TIME get_time(void *arg) { QUIC_CHANNEL *ch = arg; if (ch->now_cb == NULL) return ossl_time_now(); return ch->now_cb(ch->now_cb_arg); } /* Used by QSM. */ static uint64_t get_stream_limit(int uni, void *arg) { QUIC_CHANNEL *ch = arg; return uni ? ch->max_local_streams_uni : ch->max_local_streams_bidi; } /* * Called by QRX to determine if a packet is potentially invalid before trying * to decrypt it. */ static int rx_early_validate(QUIC_PN pn, int pn_space, void *arg) { QUIC_CHANNEL *ch = arg; /* Potential duplicates should not be processed. */ if (!ossl_ackm_is_rx_pn_processable(ch->ackm, pn, pn_space)) return 0; return 1; } /* * QUIC Channel: Handshake Layer Event Handling * ============================================ */ static int ch_on_crypto_send(const unsigned char *buf, size_t buf_len, size_t *consumed, void *arg) { int ret; QUIC_CHANNEL *ch = arg; uint32_t enc_level = ch->tx_enc_level; uint32_t pn_space = ossl_quic_enc_level_to_pn_space(enc_level); QUIC_SSTREAM *sstream = ch->crypto_send[pn_space]; if (!ossl_assert(sstream != NULL)) return 0; ret = ossl_quic_sstream_append(sstream, buf, buf_len, consumed); return ret; } static int crypto_ensure_empty(QUIC_RSTREAM *rstream) { size_t avail = 0; int is_fin = 0; if (rstream == NULL) return 1; if (!ossl_quic_rstream_available(rstream, &avail, &is_fin)) return 0; return avail == 0; } static int ch_on_crypto_recv_record(const unsigned char **buf, size_t *bytes_read, void *arg) { QUIC_CHANNEL *ch = arg; QUIC_RSTREAM *rstream; int is_fin = 0; /* crypto stream is never finished, so we don't use this */ uint32_t i; /* * After we move to a later EL we must not allow our peer to send any new * bytes in the crypto stream on a previous EL. Retransmissions of old bytes * are allowed. * * In practice we will only move to a new EL when we have consumed all bytes * which should be sent on the crypto stream at a previous EL. For example, * the Handshake EL should not be provisioned until we have completely * consumed a TLS 1.3 ServerHello. Thus when we provision an EL the output * of ossl_quic_rstream_available() should be 0 for all lower ELs. Thus if a * given EL is available we simply ensure we have not received any further * bytes at a lower EL. */ for (i = QUIC_ENC_LEVEL_INITIAL; i < ch->rx_enc_level; ++i) if (i != QUIC_ENC_LEVEL_0RTT && !crypto_ensure_empty(ch->crypto_recv[ossl_quic_enc_level_to_pn_space(i)])) { /* Protocol violation (RFC 9001 s. 4.1.3) */ ossl_quic_channel_raise_protocol_error(ch, QUIC_ERR_PROTOCOL_VIOLATION, OSSL_QUIC_FRAME_TYPE_CRYPTO, "crypto stream data in wrong EL"); return 0; } rstream = ch->crypto_recv[ossl_quic_enc_level_to_pn_space(ch->rx_enc_level)]; if (rstream == NULL) return 0; return ossl_quic_rstream_get_record(rstream, buf, bytes_read, &is_fin); } static int ch_on_crypto_release_record(size_t bytes_read, void *arg) { QUIC_CHANNEL *ch = arg; QUIC_RSTREAM *rstream; rstream = ch->crypto_recv[ossl_quic_enc_level_to_pn_space(ch->rx_enc_level)]; if (rstream == NULL) return 0; return ossl_quic_rstream_release_record(rstream, bytes_read); } static int ch_on_handshake_yield_secret(uint32_t enc_level, int direction, uint32_t suite_id, EVP_MD *md, const unsigned char *secret, size_t secret_len, void *arg) { QUIC_CHANNEL *ch = arg; uint32_t i; if (enc_level < QUIC_ENC_LEVEL_HANDSHAKE || enc_level >= QUIC_ENC_LEVEL_NUM) /* Invalid EL. */ return 0; if (direction) { /* TX */ if (enc_level <= ch->tx_enc_level) /* * Does not make sense for us to try and provision an EL we have already * attained. */ return 0; if (!ossl_qtx_provide_secret(ch->qtx, enc_level, suite_id, md, secret, secret_len)) return 0; ch->tx_enc_level = enc_level; } else { /* RX */ if (enc_level <= ch->rx_enc_level) /* * Does not make sense for us to try and provision an EL we have already * attained. */ return 0; /* * Ensure all crypto streams for previous ELs are now empty of available * data. */ for (i = QUIC_ENC_LEVEL_INITIAL; i < enc_level; ++i) if (!crypto_ensure_empty(ch->crypto_recv[ossl_quic_enc_level_to_pn_space(i)])) { /* Protocol violation (RFC 9001 s. 4.1.3) */ ossl_quic_channel_raise_protocol_error(ch, QUIC_ERR_PROTOCOL_VIOLATION, OSSL_QUIC_FRAME_TYPE_CRYPTO, "crypto stream data in wrong EL"); return 0; } if (!ossl_qrx_provide_secret(ch->qrx, enc_level, suite_id, md, secret, secret_len)) return 0; ch->have_new_rx_secret = 1; ch->rx_enc_level = enc_level; } return 1; } static int ch_on_handshake_complete(void *arg) { QUIC_CHANNEL *ch = arg; if (!ossl_assert(!ch->handshake_complete)) return 0; /* this should not happen twice */ if (!ossl_assert(ch->tx_enc_level == QUIC_ENC_LEVEL_1RTT)) return 0; if (!ch->got_remote_transport_params) { /* * Was not a valid QUIC handshake if we did not get valid transport * params. */ ossl_quic_channel_raise_protocol_error(ch, QUIC_ERR_PROTOCOL_VIOLATION, OSSL_QUIC_FRAME_TYPE_CRYPTO, "no transport parameters received"); return 0; } /* Don't need transport parameters anymore. */ OPENSSL_free(ch->local_transport_params); ch->local_transport_params = NULL; /* Tell TXP the handshake is complete. */ ossl_quic_tx_packetiser_notify_handshake_complete(ch->txp); ch->handshake_complete = 1; if (ch->is_server) { /* * On the server, the handshake is confirmed as soon as it is complete. */ ossl_quic_channel_on_handshake_confirmed(ch); ossl_quic_tx_packetiser_schedule_handshake_done(ch->txp); } return 1; } static int ch_on_handshake_alert(void *arg, unsigned char alert_code) { QUIC_CHANNEL *ch = arg; ossl_quic_channel_raise_protocol_error(ch, QUIC_ERR_CRYPTO_ERR_BEGIN + alert_code, 0, "handshake alert"); return 1; } /* * QUIC Channel: Transport Parameter Handling * ========================================== */ /* * Called by handshake layer when we receive QUIC Transport Parameters from the * peer. Note that these are not authenticated until the handshake is marked * as complete. */ #define TP_REASON_SERVER_ONLY(x) \ x " may not be sent by a client" #define TP_REASON_DUP(x) \ x " appears multiple times" #define TP_REASON_MALFORMED(x) \ x " is malformed" #define TP_REASON_EXPECTED_VALUE(x) \ x " does not match expected value" #define TP_REASON_NOT_RETRY(x) \ x " sent when not performing a retry" #define TP_REASON_REQUIRED(x) \ x " was not sent but is required" static int ch_on_transport_params(const unsigned char *params, size_t params_len, void *arg) { QUIC_CHANNEL *ch = arg; PACKET pkt; uint64_t id, v; size_t len; const unsigned char *body; int got_orig_dcid = 0; int got_initial_scid = 0; int got_retry_scid = 0; int got_initial_max_data = 0; int got_initial_max_stream_data_bidi_local = 0; int got_initial_max_stream_data_bidi_remote = 0; int got_initial_max_stream_data_uni = 0; int got_initial_max_streams_bidi = 0; int got_initial_max_streams_uni = 0; int got_ack_delay_exp = 0; int got_max_ack_delay = 0; int got_max_udp_payload_size = 0; int got_max_idle_timeout = 0; int got_active_conn_id_limit = 0; QUIC_CONN_ID cid; const char *reason = "bad transport parameter"; if (ch->got_remote_transport_params) goto malformed; if (!PACKET_buf_init(&pkt, params, params_len)) return 0; while (PACKET_remaining(&pkt) > 0) { if (!ossl_quic_wire_peek_transport_param(&pkt, &id)) goto malformed; switch (id) { case QUIC_TPARAM_ORIG_DCID: if (got_orig_dcid) { reason = TP_REASON_DUP("ORIG_DCID"); goto malformed; } if (ch->is_server) { reason = TP_REASON_SERVER_ONLY("ORIG_DCID"); goto malformed; } if (!ossl_quic_wire_decode_transport_param_cid(&pkt, NULL, &cid)) { reason = TP_REASON_MALFORMED("ORIG_DCID"); goto malformed; } /* Must match our initial DCID. */ if (!ossl_quic_conn_id_eq(&ch->init_dcid, &cid)) { reason = TP_REASON_EXPECTED_VALUE("ORIG_DCID"); goto malformed; } got_orig_dcid = 1; break; case QUIC_TPARAM_RETRY_SCID: if (ch->is_server) { reason = TP_REASON_SERVER_ONLY("RETRY_SCID"); goto malformed; } if (got_retry_scid) { reason = TP_REASON_DUP("RETRY_SCID"); goto malformed; } if (!ch->doing_retry) { reason = TP_REASON_NOT_RETRY("RETRY_SCID"); goto malformed; } if (!ossl_quic_wire_decode_transport_param_cid(&pkt, NULL, &cid)) { reason = TP_REASON_MALFORMED("RETRY_SCID"); goto malformed; } /* Must match Retry packet SCID. */ if (!ossl_quic_conn_id_eq(&ch->retry_scid, &cid)) { reason = TP_REASON_EXPECTED_VALUE("RETRY_SCID"); goto malformed; } got_retry_scid = 1; break; case QUIC_TPARAM_INITIAL_SCID: if (got_initial_scid) { /* must not appear more than once */ reason = TP_REASON_DUP("INITIAL_SCID"); goto malformed; } if (!ossl_quic_wire_decode_transport_param_cid(&pkt, NULL, &cid)) { reason = TP_REASON_MALFORMED("INITIAL_SCID"); goto malformed; } /* Must match SCID of first Initial packet from server. */ if (!ossl_quic_conn_id_eq(&ch->init_scid, &cid)) { reason = TP_REASON_EXPECTED_VALUE("INITIAL_SCID"); goto malformed; } got_initial_scid = 1; break; case QUIC_TPARAM_INITIAL_MAX_DATA: if (got_initial_max_data) { /* must not appear more than once */ reason = TP_REASON_DUP("INITIAL_MAX_DATA"); goto malformed; } if (!ossl_quic_wire_decode_transport_param_int(&pkt, &id, &v)) { reason = TP_REASON_MALFORMED("INITIAL_MAX_DATA"); goto malformed; } ossl_quic_txfc_bump_cwm(&ch->conn_txfc, v); got_initial_max_data = 1; break; case QUIC_TPARAM_INITIAL_MAX_STREAM_DATA_BIDI_LOCAL: if (got_initial_max_stream_data_bidi_local) { /* must not appear more than once */ reason = TP_REASON_DUP("INITIAL_MAX_STREAM_DATA_BIDI_LOCAL"); goto malformed; } if (!ossl_quic_wire_decode_transport_param_int(&pkt, &id, &v)) { reason = TP_REASON_MALFORMED("INITIAL_MAX_STREAM_DATA_BIDI_LOCAL"); goto malformed; } /* * This is correct; the BIDI_LOCAL TP governs streams created by * the endpoint which sends the TP, i.e., our peer. */ ch->init_max_stream_data_bidi_remote = v; got_initial_max_stream_data_bidi_local = 1; break; case QUIC_TPARAM_INITIAL_MAX_STREAM_DATA_BIDI_REMOTE: if (got_initial_max_stream_data_bidi_remote) { /* must not appear more than once */ reason = TP_REASON_DUP("INITIAL_MAX_STREAM_DATA_BIDI_REMOTE"); goto malformed; } if (!ossl_quic_wire_decode_transport_param_int(&pkt, &id, &v)) { reason = TP_REASON_MALFORMED("INITIAL_MAX_STREAM_DATA_BIDI_REMOTE"); goto malformed; } /* * This is correct; the BIDI_REMOTE TP governs streams created * by the endpoint which receives the TP, i.e., us. */ ch->init_max_stream_data_bidi_local = v; /* Apply to stream 0. */ ossl_quic_txfc_bump_cwm(&ch->stream0->txfc, v); got_initial_max_stream_data_bidi_remote = 1; break; case QUIC_TPARAM_INITIAL_MAX_STREAM_DATA_UNI: if (got_initial_max_stream_data_uni) { /* must not appear more than once */ reason = TP_REASON_DUP("INITIAL_MAX_STREAM_DATA_UNI"); goto malformed; } if (!ossl_quic_wire_decode_transport_param_int(&pkt, &id, &v)) { reason = TP_REASON_MALFORMED("INITIAL_MAX_STREAM_DATA_UNI"); goto malformed; } ch->init_max_stream_data_uni_remote = v; got_initial_max_stream_data_uni = 1; break; case QUIC_TPARAM_ACK_DELAY_EXP: if (got_ack_delay_exp) { /* must not appear more than once */ reason = TP_REASON_DUP("ACK_DELAY_EXP"); goto malformed; } if (!ossl_quic_wire_decode_transport_param_int(&pkt, &id, &v) || v > QUIC_MAX_ACK_DELAY_EXP) { reason = TP_REASON_MALFORMED("ACK_DELAY_EXP"); goto malformed; } ch->rx_ack_delay_exp = (unsigned char)v; got_ack_delay_exp = 1; break; case QUIC_TPARAM_MAX_ACK_DELAY: if (got_max_ack_delay) { /* must not appear more than once */ reason = TP_REASON_DUP("MAX_ACK_DELAY"); return 0; } if (!ossl_quic_wire_decode_transport_param_int(&pkt, &id, &v) || v >= (((uint64_t)1) << 14)) { reason = TP_REASON_MALFORMED("MAX_ACK_DELAY"); goto malformed; } ch->rx_max_ack_delay = v; got_max_ack_delay = 1; break; case QUIC_TPARAM_INITIAL_MAX_STREAMS_BIDI: if (got_initial_max_streams_bidi) { /* must not appear more than once */ reason = TP_REASON_DUP("INITIAL_MAX_STREAMS_BIDI"); return 0; } if (!ossl_quic_wire_decode_transport_param_int(&pkt, &id, &v) || v > (((uint64_t)1) << 60)) { reason = TP_REASON_MALFORMED("INITIAL_MAX_STREAMS_BIDI"); goto malformed; } assert(ch->max_local_streams_bidi == 0); ch->max_local_streams_bidi = v; got_initial_max_streams_bidi = 1; break; case QUIC_TPARAM_INITIAL_MAX_STREAMS_UNI: if (got_initial_max_streams_uni) { /* must not appear more than once */ reason = TP_REASON_DUP("INITIAL_MAX_STREAMS_UNI"); goto malformed; } if (!ossl_quic_wire_decode_transport_param_int(&pkt, &id, &v) || v > (((uint64_t)1) << 60)) { reason = TP_REASON_MALFORMED("INITIAL_MAX_STREAMS_UNI"); goto malformed; } assert(ch->max_local_streams_uni == 0); ch->max_local_streams_uni = v; got_initial_max_streams_uni = 1; break; case QUIC_TPARAM_MAX_IDLE_TIMEOUT: if (got_max_idle_timeout) { /* must not appear more than once */ reason = TP_REASON_DUP("MAX_IDLE_TIMEOUT"); goto malformed; } if (!ossl_quic_wire_decode_transport_param_int(&pkt, &id, &v)) { reason = TP_REASON_MALFORMED("MAX_IDLE_TIMEOUT"); goto malformed; } if (v > 0 && v < ch->max_idle_timeout) ch->max_idle_timeout = v; ch_update_idle(ch); got_max_idle_timeout = 1; break; case QUIC_TPARAM_MAX_UDP_PAYLOAD_SIZE: if (got_max_udp_payload_size) { /* must not appear more than once */ reason = TP_REASON_DUP("MAX_UDP_PAYLOAD_SIZE"); goto malformed; } if (!ossl_quic_wire_decode_transport_param_int(&pkt, &id, &v) || v < QUIC_MIN_INITIAL_DGRAM_LEN) { reason = TP_REASON_MALFORMED("MAX_UDP_PAYLOAD_SIZE"); goto malformed; } ch->rx_max_udp_payload_size = v; got_max_udp_payload_size = 1; break; case QUIC_TPARAM_ACTIVE_CONN_ID_LIMIT: if (got_active_conn_id_limit) { /* must not appear more than once */ reason = TP_REASON_DUP("ACTIVE_CONN_ID_LIMIT"); goto malformed; } if (!ossl_quic_wire_decode_transport_param_int(&pkt, &id, &v) || v < QUIC_MIN_ACTIVE_CONN_ID_LIMIT) { reason = TP_REASON_MALFORMED("ACTIVE_CONN_ID_LIMIT"); goto malformed; } ch->rx_active_conn_id_limit = v; got_active_conn_id_limit = 1; break; case QUIC_TPARAM_STATELESS_RESET_TOKEN: /* TODO(QUIC): Handle stateless reset tokens. */ /* * We ignore these for now, but we must ensure a client doesn't * send them. */ if (ch->is_server) { reason = TP_REASON_SERVER_ONLY("STATELESS_RESET_TOKEN"); goto malformed; } body = ossl_quic_wire_decode_transport_param_bytes(&pkt, &id, &len); if (body == NULL || len != QUIC_STATELESS_RESET_TOKEN_LEN) { reason = TP_REASON_MALFORMED("STATELESS_RESET_TOKEN"); goto malformed; } break; case QUIC_TPARAM_PREFERRED_ADDR: /* TODO(QUIC): Handle preferred address. */ if (ch->is_server) { reason = TP_REASON_SERVER_ONLY("PREFERRED_ADDR"); goto malformed; } body = ossl_quic_wire_decode_transport_param_bytes(&pkt, &id, &len); if (body == NULL) { reason = TP_REASON_MALFORMED("PREFERRED_ADDR"); goto malformed; } break; case QUIC_TPARAM_DISABLE_ACTIVE_MIGRATION: /* We do not currently handle migration, so nothing to do. */ default: /* Skip over and ignore. */ body = ossl_quic_wire_decode_transport_param_bytes(&pkt, &id, &len); if (body == NULL) goto malformed; break; } } if (!got_initial_scid) { reason = TP_REASON_REQUIRED("INITIAL_SCID"); goto malformed; } if (!ch->is_server) { if (!got_orig_dcid) { reason = TP_REASON_REQUIRED("ORIG_DCID"); goto malformed; } if (ch->doing_retry && !got_retry_scid) { reason = TP_REASON_REQUIRED("RETRY_SCID"); goto malformed; } } ch->got_remote_transport_params = 1; if (got_initial_max_data || got_initial_max_stream_data_bidi_remote || got_initial_max_streams_bidi || got_initial_max_streams_uni) /* If FC credit was bumped, we may now be able to send. */ ossl_quic_stream_map_update_state(&ch->qsm, ch->stream0); /* If we are a server, we now generate our own transport parameters. */ if (ch->is_server && !ch_generate_transport_params(ch)) { ossl_quic_channel_raise_protocol_error(ch, QUIC_ERR_INTERNAL_ERROR, 0, "internal error"); return 0; } return 1; malformed: ossl_quic_channel_raise_protocol_error(ch, QUIC_ERR_TRANSPORT_PARAMETER_ERROR, 0, reason); return 0; } /* * Called when we want to generate transport parameters. This is called * immediately at instantiation time for a client and after we receive the * client's transport parameters for a server. */ static int ch_generate_transport_params(QUIC_CHANNEL *ch) { int ok = 0; BUF_MEM *buf_mem = NULL; WPACKET wpkt; int wpkt_valid = 0; size_t buf_len = 0; if (ch->local_transport_params != NULL) goto err; if ((buf_mem = BUF_MEM_new()) == NULL) goto err; if (!WPACKET_init(&wpkt, buf_mem)) goto err; wpkt_valid = 1; if (ossl_quic_wire_encode_transport_param_bytes(&wpkt, QUIC_TPARAM_DISABLE_ACTIVE_MIGRATION, NULL, 0) == NULL) goto err; if (ch->is_server) { if (!ossl_quic_wire_encode_transport_param_cid(&wpkt, QUIC_TPARAM_ORIG_DCID, &ch->init_dcid)) goto err; if (!ossl_quic_wire_encode_transport_param_cid(&wpkt, QUIC_TPARAM_INITIAL_SCID, &ch->cur_local_dcid)) goto err; } else { /* Client always uses an empty SCID. */ if (ossl_quic_wire_encode_transport_param_bytes(&wpkt, QUIC_TPARAM_INITIAL_SCID, NULL, 0) == NULL) goto err; } if (!ossl_quic_wire_encode_transport_param_int(&wpkt, QUIC_TPARAM_MAX_IDLE_TIMEOUT, ch->max_idle_timeout)) goto err; if (!ossl_quic_wire_encode_transport_param_int(&wpkt, QUIC_TPARAM_MAX_UDP_PAYLOAD_SIZE, QUIC_MIN_INITIAL_DGRAM_LEN)) goto err; if (!ossl_quic_wire_encode_transport_param_int(&wpkt, QUIC_TPARAM_ACTIVE_CONN_ID_LIMIT, 4)) goto err; if (!ossl_quic_wire_encode_transport_param_int(&wpkt, QUIC_TPARAM_INITIAL_MAX_DATA, ossl_quic_rxfc_get_cwm(&ch->conn_rxfc))) goto err; /* * We actually want the default CWM for a new RXFC, but here we just use * stream0 as a representative specimen. TODO(QUIC): revisit this when we * support multiple streams. */ if (!ossl_quic_wire_encode_transport_param_int(&wpkt, QUIC_TPARAM_INITIAL_MAX_STREAM_DATA_BIDI_LOCAL, ossl_quic_rxfc_get_cwm(&ch->stream0->rxfc))) goto err; if (!ossl_quic_wire_encode_transport_param_int(&wpkt, QUIC_TPARAM_INITIAL_MAX_STREAM_DATA_BIDI_REMOTE, ossl_quic_rxfc_get_cwm(&ch->stream0->rxfc))) goto err; if (!ossl_quic_wire_encode_transport_param_int(&wpkt, QUIC_TPARAM_INITIAL_MAX_STREAM_DATA_UNI, ossl_quic_rxfc_get_cwm(&ch->stream0->rxfc))) goto err; if (!ossl_quic_wire_encode_transport_param_int(&wpkt, QUIC_TPARAM_INITIAL_MAX_STREAMS_BIDI, ch->is_server ? 1 : 0)) goto err; if (!ossl_quic_wire_encode_transport_param_int(&wpkt, QUIC_TPARAM_INITIAL_MAX_STREAMS_UNI, 0)) goto err; if (!WPACKET_get_total_written(&wpkt, &buf_len)) goto err; ch->local_transport_params = (unsigned char *)buf_mem->data; buf_mem->data = NULL; if (!WPACKET_finish(&wpkt)) goto err; wpkt_valid = 0; if (!ossl_quic_tls_set_transport_params(ch->qtls, ch->local_transport_params, buf_len)) goto err; ok = 1; err: if (wpkt_valid) WPACKET_cleanup(&wpkt); BUF_MEM_free(buf_mem); return ok; } /* * QUIC Channel: Ticker-Mutator * ============================ */ /* * The central ticker function called by the reactor. This does everything, or * at least everything network I/O related. Best effort - not allowed to fail * "loudly". */ static void ch_tick(QUIC_TICK_RESULT *res, void *arg, uint32_t flags) { OSSL_TIME now, deadline; QUIC_CHANNEL *ch = arg; int channel_only = (flags & QUIC_REACTOR_TICK_FLAG_CHANNEL_ONLY) != 0; /* * When we tick the QUIC connection, we do everything we need to do * periodically. In order, we: * * - handle any incoming data from the network; * - handle any timer events which are due to fire (ACKM, etc.) * - write any data to the network due to be sent, to the extent * possible; * - determine the time at which we should next be ticked. */ /* If we are in the TERMINATED state, there is nothing to do. */ if (ossl_quic_channel_is_terminated(ch)) { res->net_read_desired = 0; res->net_write_desired = 0; res->tick_deadline = ossl_time_infinite(); return; } /* * If we are in the TERMINATING state, check if the terminating timer has * expired. */ if (ossl_quic_channel_is_terminating(ch)) { now = get_time(ch); if (ossl_time_compare(now, ch->terminate_deadline) >= 0) { ch_on_terminating_timeout(ch); res->net_read_desired = 0; res->net_write_desired = 0; res->tick_deadline = ossl_time_infinite(); return; /* abort normal processing, nothing to do */ } } /* Handle any incoming data from network. */ ch_rx_pre(ch); do { /* Process queued incoming packets. */ ch_rx(ch); /* * Allow the handshake layer to check for any new incoming data and generate * new outgoing data. */ ch->have_new_rx_secret = 0; if (!channel_only) ossl_quic_tls_tick(ch->qtls); /* * If the handshake layer gave us a new secret, we need to do RX again * because packets that were not previously processable and were * deferred might now be processable. * * TODO(QUIC): Consider handling this in the yield_secret callback. */ } while (ch->have_new_rx_secret); /* * Handle any timer events which are due to fire; namely, the loss detection * deadline and the idle timeout. * * ACKM ACK generation deadline is polled by TXP, so we don't need to handle * it here. */ now = get_time(ch); if (ossl_time_compare(now, ch->idle_deadline) >= 0) { /* * Idle timeout differs from normal protocol violation because we do not * send a CONN_CLOSE frame; go straight to TERMINATED. */ ch_on_idle_timeout(ch); res->net_read_desired = 0; res->net_write_desired = 0; res->tick_deadline = ossl_time_infinite(); return; } deadline = ossl_ackm_get_loss_detection_deadline(ch->ackm); if (!ossl_time_is_zero(deadline) && ossl_time_compare(now, deadline) >= 0) ossl_ackm_on_timeout(ch->ackm); /* If a ping is due, inform TXP. */ if (ossl_time_compare(now, ch->ping_deadline) >= 0) { int pn_space = ossl_quic_enc_level_to_pn_space(ch->tx_enc_level); ossl_quic_tx_packetiser_schedule_ack_eliciting(ch->txp, pn_space); } /* Write any data to the network due to be sent. */ ch_tx(ch); /* Determine the time at which we should next be ticked. */ res->tick_deadline = ch_determine_next_tick_deadline(ch); /* * Always process network input unless we are now terminated. * Although we had not terminated at the beginning of this tick, network * errors in ch_rx_pre() or ch_tx() may have caused us to transition to the * Terminated state. */ res->net_read_desired = !ossl_quic_channel_is_terminated(ch); /* We want to write to the network if we have any in our queue. */ res->net_write_desired = (!ossl_quic_channel_is_terminated(ch) && ossl_qtx_get_queue_len_datagrams(ch->qtx) > 0); } /* Process incoming datagrams, if any. */ static void ch_rx_pre(QUIC_CHANNEL *ch) { int ret; if (!ch->is_server && !ch->have_sent_any_pkt) return; /* * Get DEMUX to BIO_recvmmsg from the network and queue incoming datagrams * to the appropriate QRX instance. */ ret = ossl_quic_demux_pump(ch->demux); if (ret == QUIC_DEMUX_PUMP_RES_PERMANENT_FAIL) /* * We don't care about transient failure, but permanent failure means we * should tear down the connection as though a protocol violation * occurred. Skip straight to the Terminating state as there is no point * trying to send CONNECTION_CLOSE frames if the network BIO is not * operating correctly. */ ch_raise_net_error(ch); } /* Process queued incoming packets and handle frames, if any. */ static int ch_rx(QUIC_CHANNEL *ch) { int handled_any = 0; if (!ch->is_server && !ch->have_sent_any_pkt) /* * We have not sent anything yet, therefore there is no need to check * for incoming data. */ return 1; for (;;) { assert(ch->qrx_pkt == NULL); if (!ossl_qrx_read_pkt(ch->qrx, &ch->qrx_pkt)) break; if (!handled_any) ch_update_idle(ch); ch_rx_handle_packet(ch); /* best effort */ /* * Regardless of the outcome of frame handling, unref the packet. * This will free the packet unless something added another * reference to it during frame processing. */ ossl_qrx_pkt_release(ch->qrx_pkt); ch->qrx_pkt = NULL; ch->have_sent_ack_eliciting_since_rx = 0; handled_any = 1; } /* * When in TERMINATING - CLOSING, generate a CONN_CLOSE frame whenever we * process one or more incoming packets. */ if (handled_any && ch->state == QUIC_CHANNEL_STATE_TERMINATING_CLOSING) ch->conn_close_queued = 1; return 1; } /* Handles the packet currently in ch->qrx_pkt->hdr. */ static void ch_rx_handle_packet(QUIC_CHANNEL *ch) { uint32_t enc_level; assert(ch->qrx_pkt != NULL); if (ossl_quic_pkt_type_is_encrypted(ch->qrx_pkt->hdr->type)) { if (!ch->have_received_enc_pkt) { ch->init_scid = ch->qrx_pkt->hdr->src_conn_id; ch->have_received_enc_pkt = 1; /* * We change to using the SCID in the first Initial packet as the * DCID. */ ossl_quic_tx_packetiser_set_cur_dcid(ch->txp, &ch->init_scid); } enc_level = ossl_quic_pkt_type_to_enc_level(ch->qrx_pkt->hdr->type); if ((ch->el_discarded & (1U << enc_level)) != 0) /* Do not process packets from ELs we have already discarded. */ return; } /* Handle incoming packet. */ switch (ch->qrx_pkt->hdr->type) { case QUIC_PKT_TYPE_RETRY: if (ch->doing_retry || ch->is_server) /* * It is not allowed to ask a client to do a retry more than * once. Clients may not send retries. */ return; if (ch->qrx_pkt->hdr->len <= QUIC_RETRY_INTEGRITY_TAG_LEN) /* Packets with zero-length Retry Tokens are invalid. */ return; /* * TODO(QUIC): Theoretically this should probably be in the QRX. * However because validation is dependent on context (namely the * client's initial DCID) we can't do this cleanly. In the future we * should probably add a callback to the QRX to let it call us (via * the DEMUX) and ask us about the correct original DCID, rather * than allow the QRX to emit a potentially malformed packet to the * upper layers. However, special casing this will do for now. */ if (!ossl_quic_validate_retry_integrity_tag(ch->libctx, ch->propq, ch->qrx_pkt->hdr, &ch->init_dcid)) /* Malformed retry packet, ignore. */ return; ch_retry(ch, ch->qrx_pkt->hdr->data, ch->qrx_pkt->hdr->len - QUIC_RETRY_INTEGRITY_TAG_LEN, &ch->qrx_pkt->hdr->src_conn_id); break; case QUIC_PKT_TYPE_0RTT: if (!ch->is_server) /* Clients should never receive 0-RTT packets. */ return; /* * TODO(QUIC): Implement 0-RTT on the server side. We currently do * not need to implement this as a client can only do 0-RTT if we * have given it permission to in a previous session. */ break; case QUIC_PKT_TYPE_INITIAL: case QUIC_PKT_TYPE_HANDSHAKE: case QUIC_PKT_TYPE_1RTT: if (ch->qrx_pkt->hdr->type == QUIC_PKT_TYPE_HANDSHAKE) /* * We automatically drop INITIAL EL keys when first successfully * decrypting a HANDSHAKE packet, as per the RFC. */ ch_discard_el(ch, QUIC_ENC_LEVEL_INITIAL); /* This packet contains frames, pass to the RXDP. */ ossl_quic_handle_frames(ch, ch->qrx_pkt); /* best effort */ break; default: assert(0); break; } } /* * This is called by the demux when we get a packet not destined for any known * DCID. */ static void ch_default_packet_handler(QUIC_URXE *e, void *arg) { QUIC_CHANNEL *ch = arg; PACKET pkt; QUIC_PKT_HDR hdr; if (!ossl_assert(ch->is_server)) goto undesirable; /* * We only support one connection to our server currently, so if we already * started one, ignore any new connection attempts. */ if (ch->state != QUIC_CHANNEL_STATE_IDLE) goto undesirable; /* * We have got a packet for an unknown DCID. This might be an attempt to * open a new connection. */ if (e->data_len < QUIC_MIN_INITIAL_DGRAM_LEN) goto undesirable; if (!PACKET_buf_init(&pkt, ossl_quic_urxe_data(e), e->data_len)) goto err; /* * We set short_conn_id_len to SIZE_MAX here which will cause the decode * operation to fail if we get a 1-RTT packet. This is fine since we only * care about Initial packets. */ if (!ossl_quic_wire_decode_pkt_hdr(&pkt, SIZE_MAX, 1, &hdr, NULL)) goto undesirable; switch (hdr.version) { case QUIC_VERSION_1: break; case QUIC_VERSION_NONE: default: /* Unknown version or proactive version negotiation request, bail. */ /* TODO(QUIC): Handle version negotiation on server side */ goto undesirable; } /* * We only care about Initial packets which might be trying to establish a * connection. */ if (hdr.type != QUIC_PKT_TYPE_INITIAL) goto undesirable; /* * Assume this is a valid attempt to initiate a connection. * * We do not register the DCID in the initial packet we received and that * DCID is not actually used again, thus after provisioning the correct * Initial keys derived from it (which is done in the call below) we pass * the received packet directly to the QRX so that it can process it as a * one-time thing, instead of going through the usual DEMUX DCID-based * routing. */ if (!ch_server_on_new_conn(ch, &e->peer, &hdr.src_conn_id, &hdr.dst_conn_id)) goto err; ossl_qrx_inject_urxe(ch->qrx, e); return; err: ossl_quic_channel_raise_protocol_error(ch, QUIC_ERR_INTERNAL_ERROR, 0, "internal error"); undesirable: ossl_quic_demux_release_urxe(ch->demux, e); } /* Try to generate packets and if possible, flush them to the network. */ static int ch_tx(QUIC_CHANNEL *ch) { int sent_ack_eliciting = 0; if (ch->state == QUIC_CHANNEL_STATE_TERMINATING_CLOSING) { /* * While closing, only send CONN_CLOSE if we've received more traffic * from the peer. Once we tell the TXP to generate CONN_CLOSE, all * future calls to it generate CONN_CLOSE frames, so otherwise we would * just constantly generate CONN_CLOSE frames. */ if (!ch->conn_close_queued) return 0; ch->conn_close_queued = 0; } /* * Send a packet, if we need to. Best effort. The TXP consults the CC and * applies any limitations imposed by it, so we don't need to do it here. * * Best effort. In particular if TXP fails for some reason we should still * flush any queued packets which we already generated. */ switch (ossl_quic_tx_packetiser_generate(ch->txp, TX_PACKETISER_ARCHETYPE_NORMAL, &sent_ack_eliciting)) { case TX_PACKETISER_RES_SENT_PKT: ch->have_sent_any_pkt = 1; /* Packet was sent */ /* * RFC 9000 s. 10.1. 'An endpoint also restarts its idle timer when * sending an ack-eliciting packet if no other ack-eliciting packets * have been sent since last receiving and processing a packet.' */ if (sent_ack_eliciting && !ch->have_sent_ack_eliciting_since_rx) { ch_update_idle(ch); ch->have_sent_ack_eliciting_since_rx = 1; } ch_update_ping_deadline(ch); break; case TX_PACKETISER_RES_NO_PKT: break; /* No packet was sent */ default: ossl_quic_channel_raise_protocol_error(ch, QUIC_ERR_INTERNAL_ERROR, 0, "internal error"); break; /* Internal failure (e.g. allocation, assertion) */ } /* Flush packets to network. */ switch (ossl_qtx_flush_net(ch->qtx)) { case QTX_FLUSH_NET_RES_OK: case QTX_FLUSH_NET_RES_TRANSIENT_FAIL: /* Best effort, done for now. */ break; case QTX_FLUSH_NET_RES_PERMANENT_FAIL: default: /* Permanent underlying network BIO, start terminating. */ ch_raise_net_error(ch); break; } return 1; } /* Determine next tick deadline. */ static OSSL_TIME ch_determine_next_tick_deadline(QUIC_CHANNEL *ch) { OSSL_TIME deadline; uint32_t pn_space; if (ossl_quic_channel_is_terminated(ch)) return ossl_time_infinite(); deadline = ossl_ackm_get_loss_detection_deadline(ch->ackm); if (ossl_time_is_zero(deadline)) deadline = ossl_time_infinite(); for (pn_space = QUIC_PN_SPACE_INITIAL; pn_space < QUIC_PN_SPACE_NUM; ++pn_space) deadline = ossl_time_min(deadline, ossl_ackm_get_ack_deadline(ch->ackm, pn_space)); /* When will CC let us send more? */ if (ossl_quic_tx_packetiser_has_pending(ch->txp, TX_PACKETISER_ARCHETYPE_NORMAL, TX_PACKETISER_BYPASS_CC)) deadline = ossl_time_min(deadline, ch->cc_method->get_next_credit_time(ch->cc_data)); /* Is the terminating timer armed? */ if (ossl_quic_channel_is_terminating(ch)) deadline = ossl_time_min(deadline, ch->terminate_deadline); else if (!ossl_time_is_infinite(ch->idle_deadline)) deadline = ossl_time_min(deadline, ch->idle_deadline); /* * When do we need to send an ACK-eliciting packet to reset the idle * deadline timer for the peer? */ if (!ossl_time_is_infinite(ch->ping_deadline)) deadline = ossl_time_min(deadline, ch->ping_deadline); return deadline; } /* * QUIC Channel: Network BIO Configuration * ======================================= */ /* Determines whether we can support a given poll descriptor. */ static int validate_poll_descriptor(const BIO_POLL_DESCRIPTOR *d) { if (d->type == BIO_POLL_DESCRIPTOR_TYPE_SOCK_FD && d->value.fd < 0) return 0; return 1; } BIO *ossl_quic_channel_get_net_rbio(QUIC_CHANNEL *ch) { return ch->net_rbio; } BIO *ossl_quic_channel_get_net_wbio(QUIC_CHANNEL *ch) { return ch->net_wbio; } /* * QUIC_CHANNEL does not ref any BIO it is provided with, nor is any ref * transferred to it. The caller (i.e., QUIC_CONNECTION) is responsible for * ensuring the BIO lasts until the channel is freed or the BIO is switched out * for another BIO by a subsequent successful call to this function. */ int ossl_quic_channel_set_net_rbio(QUIC_CHANNEL *ch, BIO *net_rbio) { BIO_POLL_DESCRIPTOR d = {0}; if (ch->net_rbio == net_rbio) return 1; if (net_rbio != NULL) { if (!BIO_get_rpoll_descriptor(net_rbio, &d)) /* Non-pollable BIO */ d.type = BIO_POLL_DESCRIPTOR_TYPE_NONE; if (!validate_poll_descriptor(&d)) return 0; } ossl_quic_reactor_set_poll_r(&ch->rtor, &d); ossl_quic_demux_set_bio(ch->demux, net_rbio); ch->net_rbio = net_rbio; return 1; } int ossl_quic_channel_set_net_wbio(QUIC_CHANNEL *ch, BIO *net_wbio) { BIO_POLL_DESCRIPTOR d = {0}; if (ch->net_wbio == net_wbio) return 1; if (net_wbio != NULL) { if (!BIO_get_wpoll_descriptor(net_wbio, &d)) /* Non-pollable BIO */ d.type = BIO_POLL_DESCRIPTOR_TYPE_NONE; if (!validate_poll_descriptor(&d)) return 0; } ossl_quic_reactor_set_poll_w(&ch->rtor, &d); ossl_qtx_set_bio(ch->qtx, net_wbio); ch->net_wbio = net_wbio; return 1; } /* * QUIC Channel: Lifecycle Events * ============================== */ int ossl_quic_channel_start(QUIC_CHANNEL *ch) { if (ch->is_server) /* * This is not used by the server. The server moves to active * automatically on receiving an incoming connection. */ return 0; if (ch->state != QUIC_CHANNEL_STATE_IDLE) /* Calls to connect are idempotent */ return 1; /* Inform QTX of peer address. */ if (!ossl_quic_tx_packetiser_set_peer(ch->txp, &ch->cur_peer_addr)) return 0; /* Plug in secrets for the Initial EL. */ if (!ossl_quic_provide_initial_secret(ch->libctx, ch->propq, &ch->init_dcid, ch->is_server, ch->qrx, ch->qtx)) return 0; /* Change state. */ ch->state = QUIC_CHANNEL_STATE_ACTIVE; ch->doing_proactive_ver_neg = 0; /* not currently supported */ /* Handshake layer: start (e.g. send CH). */ if (!ossl_quic_tls_tick(ch->qtls)) return 0; ossl_quic_reactor_tick(&ch->rtor, 0); /* best effort */ return 1; } /* Start a locally initiated connection shutdown. */ void ossl_quic_channel_local_close(QUIC_CHANNEL *ch, uint64_t app_error_code) { QUIC_TERMINATE_CAUSE tcause = {0}; if (ossl_quic_channel_is_term_any(ch)) return; tcause.app = 1; tcause.error_code = app_error_code; ch_start_terminating(ch, &tcause, 0); } static void free_token(const unsigned char *buf, size_t buf_len, void *arg) { OPENSSL_free((unsigned char *)buf); } /* Called when a server asks us to do a retry. */ static int ch_retry(QUIC_CHANNEL *ch, const unsigned char *retry_token, size_t retry_token_len, const QUIC_CONN_ID *retry_scid) { void *buf; /* We change to using the SCID in the Retry packet as the DCID. */ if (!ossl_quic_tx_packetiser_set_cur_dcid(ch->txp, retry_scid)) return 0; /* * Now we retry. We will release the Retry packet immediately, so copy * the token. */ if ((buf = OPENSSL_memdup(retry_token, retry_token_len)) == NULL) return 0; ossl_quic_tx_packetiser_set_initial_token(ch->txp, buf, retry_token_len, free_token, NULL); ch->retry_scid = *retry_scid; ch->doing_retry = 1; /* * We need to stimulate the Initial EL to generate the first CRYPTO frame * again. We can do this most cleanly by simply forcing the ACKM to consider * the first Initial packet as lost, which it effectively was as the server * hasn't processed it. This also maintains the desired behaviour with e.g. * PNs not resetting and so on. * * The PN we used initially is always zero, because QUIC does not allow * repeated retries. */ if (!ossl_ackm_mark_packet_pseudo_lost(ch->ackm, QUIC_PN_SPACE_INITIAL, /*PN=*/0)) return 0; /* * Plug in new secrets for the Initial EL. This is the only time we change * the secrets for an EL after we already provisioned it. */ if (!ossl_quic_provide_initial_secret(ch->libctx, ch->propq, &ch->retry_scid, /*is_server=*/0, ch->qrx, ch->qtx)) return 0; return 1; } /* Called when an EL is to be discarded. */ static int ch_discard_el(QUIC_CHANNEL *ch, uint32_t enc_level) { if (!ossl_assert(enc_level < QUIC_ENC_LEVEL_1RTT)) return 0; if ((ch->el_discarded & (1U << enc_level)) != 0) /* Already done. */ return 1; /* Best effort for all of these. */ ossl_quic_tx_packetiser_discard_enc_level(ch->txp, enc_level); ossl_qrx_discard_enc_level(ch->qrx, enc_level); ossl_qtx_discard_enc_level(ch->qtx, enc_level); if (enc_level != QUIC_ENC_LEVEL_0RTT) { uint32_t pn_space = ossl_quic_enc_level_to_pn_space(enc_level); ossl_ackm_on_pkt_space_discarded(ch->ackm, pn_space); /* We should still have crypto streams at this point. */ if (!ossl_assert(ch->crypto_send[pn_space] != NULL) || !ossl_assert(ch->crypto_recv[pn_space] != NULL)) return 0; /* Get rid of the crypto stream state for the EL. */ ossl_quic_sstream_free(ch->crypto_send[pn_space]); ch->crypto_send[pn_space] = NULL; ossl_quic_rstream_free(ch->crypto_recv[pn_space]); ch->crypto_recv[pn_space] = NULL; } ch->el_discarded |= (1U << enc_level); return 1; } /* Intended to be called by the RXDP. */ int ossl_quic_channel_on_handshake_confirmed(QUIC_CHANNEL *ch) { if (ch->handshake_confirmed) return 1; if (!ch->handshake_complete) { /* * Does not make sense for handshake to be confirmed before it is * completed. */ ossl_quic_channel_raise_protocol_error(ch, QUIC_ERR_PROTOCOL_VIOLATION, OSSL_QUIC_FRAME_TYPE_HANDSHAKE_DONE, "handshake cannot be confirmed " "before it is completed"); return 0; } ch_discard_el(ch, QUIC_ENC_LEVEL_HANDSHAKE); ch->handshake_confirmed = 1; return 1; } /* * Master function used when we want to start tearing down a connection: * * - If the connection is still IDLE we can go straight to TERMINATED; * * - If we are already TERMINATED this is a no-op. * * - If we are TERMINATING - CLOSING and we have now got a CONNECTION_CLOSE * from the peer (tcause->remote == 1), we move to TERMINATING - DRAINING. * * - If we are TERMINATING - DRAINING, we remain here until the terminating * timer expires. * * - Otherwise, we are in ACTIVE and move to TERMINATING - CLOSING. * if we caused the termination (e.g. we have sent a CONNECTION_CLOSE). Note * that we are considered to have caused a termination if we sent the first * CONNECTION_CLOSE frame, even if it is caused by a peer protocol * violation. If the peer sent the first CONNECTION_CLOSE frame, we move to * TERMINATING - DRAINING. * * We record the termination cause structure passed on the first call only. * Any successive calls have their termination cause data discarded; * once we start sending a CONNECTION_CLOSE frame, we don't change the details * in it. */ static void ch_start_terminating(QUIC_CHANNEL *ch, const QUIC_TERMINATE_CAUSE *tcause, int force_immediate) { switch (ch->state) { default: case QUIC_CHANNEL_STATE_IDLE: ch->terminate_cause = *tcause; ch_on_terminating_timeout(ch); break; case QUIC_CHANNEL_STATE_ACTIVE: ch->terminate_cause = *tcause; if (!force_immediate) { ch->state = tcause->remote ? QUIC_CHANNEL_STATE_TERMINATING_DRAINING : QUIC_CHANNEL_STATE_TERMINATING_CLOSING; ch->terminate_deadline = ossl_time_add(get_time(ch), ossl_time_multiply(ossl_ackm_get_pto_duration(ch->ackm), 3)); if (!tcause->remote) { OSSL_QUIC_FRAME_CONN_CLOSE f = {0}; /* best effort */ f.error_code = ch->terminate_cause.error_code; f.frame_type = ch->terminate_cause.frame_type; f.is_app = ch->terminate_cause.app; ossl_quic_tx_packetiser_schedule_conn_close(ch->txp, &f); ch->conn_close_queued = 1; } } else { ch_on_terminating_timeout(ch); } break; case QUIC_CHANNEL_STATE_TERMINATING_CLOSING: if (force_immediate) ch_on_terminating_timeout(ch); else if (tcause->remote) ch->state = QUIC_CHANNEL_STATE_TERMINATING_DRAINING; break; case QUIC_CHANNEL_STATE_TERMINATING_DRAINING: /* * Other than in the force-immediate case, we remain here until the * timout expires. */ if (force_immediate) ch_on_terminating_timeout(ch); break; case QUIC_CHANNEL_STATE_TERMINATED: /* No-op. */ break; } } /* For RXDP use. */ void ossl_quic_channel_on_remote_conn_close(QUIC_CHANNEL *ch, OSSL_QUIC_FRAME_CONN_CLOSE *f) { QUIC_TERMINATE_CAUSE tcause = {0}; if (!ossl_quic_channel_is_active(ch)) return; tcause.remote = 1; tcause.app = f->is_app; tcause.error_code = f->error_code; tcause.frame_type = f->frame_type; ch_start_terminating(ch, &tcause, 0); } static void ch_raise_net_error(QUIC_CHANNEL *ch) { QUIC_TERMINATE_CAUSE tcause = {0}; tcause.error_code = QUIC_ERR_INTERNAL_ERROR; /* * Skip Terminating state and go directly to Terminated, no point trying to * send CONNECTION_CLOSE if we cannot communicate. */ ch_start_terminating(ch, &tcause, 1); } void ossl_quic_channel_raise_protocol_error(QUIC_CHANNEL *ch, uint64_t error_code, uint64_t frame_type, const char *reason) { QUIC_TERMINATE_CAUSE tcause = {0}; tcause.error_code = error_code; tcause.frame_type = frame_type; ch_start_terminating(ch, &tcause, 0); } /* * Called once the terminating timer expires, meaning we move from TERMINATING * to TERMINATED. */ static void ch_on_terminating_timeout(QUIC_CHANNEL *ch) { ch->state = QUIC_CHANNEL_STATE_TERMINATED; } /* * Updates our idle deadline. Called when an event happens which should bump the * idle timeout. */ static void ch_update_idle(QUIC_CHANNEL *ch) { if (ch->max_idle_timeout == 0) ch->idle_deadline = ossl_time_infinite(); else ch->idle_deadline = ossl_time_add(get_time(ch), ossl_ms2time(ch->max_idle_timeout)); } /* * Updates our ping deadline, which determines when we next generate a ping if * we don't have any other ACK-eliciting frames to send. */ static void ch_update_ping_deadline(QUIC_CHANNEL *ch) { if (ch->max_idle_timeout > 0) { /* * Maximum amount of time without traffic before we send a PING to keep * the connection open. Usually we use max_idle_timeout/2, but ensure * the period never exceeds the assumed NAT interval to ensure NAT * devices don't have their state time out (RFC 9000 s. 10.1.2). */ OSSL_TIME max_span = ossl_time_divide(ossl_ms2time(ch->max_idle_timeout), 2); max_span = ossl_time_min(max_span, MAX_NAT_INTERVAL); ch->ping_deadline = ossl_time_add(get_time(ch), max_span); } else { ch->ping_deadline = ossl_time_infinite(); } } /* Called when the idle timeout expires. */ static void ch_on_idle_timeout(QUIC_CHANNEL *ch) { /* * Idle timeout does not have an error code associated with it because a * CONN_CLOSE is never sent for it. We shouldn't use this data once we reach * TERMINATED anyway. */ ch->terminate_cause.app = 0; ch->terminate_cause.error_code = UINT64_MAX; ch->terminate_cause.frame_type = 0; ch->state = QUIC_CHANNEL_STATE_TERMINATED; } /* Called when we, as a server, get a new incoming connection. */ static int ch_server_on_new_conn(QUIC_CHANNEL *ch, const BIO_ADDR *peer, const QUIC_CONN_ID *peer_scid, const QUIC_CONN_ID *peer_dcid) { if (!ossl_assert(ch->state == QUIC_CHANNEL_STATE_IDLE && ch->is_server)) return 0; /* Generate a SCID we will use for the connection. */ if (!gen_rand_conn_id(ch->libctx, INIT_DCID_LEN, &ch->cur_local_dcid)) return 0; /* Note our newly learnt peer address and CIDs. */ ch->cur_peer_addr = *peer; ch->init_dcid = *peer_dcid; ch->cur_remote_dcid = *peer_scid; /* Inform QTX of peer address. */ if (!ossl_quic_tx_packetiser_set_peer(ch->txp, &ch->cur_peer_addr)) return 0; /* Inform TXP of desired CIDs. */ if (!ossl_quic_tx_packetiser_set_cur_dcid(ch->txp, &ch->cur_remote_dcid)) return 0; if (!ossl_quic_tx_packetiser_set_cur_scid(ch->txp, &ch->cur_local_dcid)) return 0; /* Plug in secrets for the Initial EL. */ if (!ossl_quic_provide_initial_secret(ch->libctx, ch->propq, &ch->init_dcid, /*is_server=*/1, ch->qrx, ch->qtx)) return 0; /* Register our local DCID in the DEMUX. */ if (!ossl_qrx_add_dst_conn_id(ch->qrx, &ch->cur_local_dcid)) return 0; /* Change state. */ ch->state = QUIC_CHANNEL_STATE_ACTIVE; ch->doing_proactive_ver_neg = 0; /* not currently supported */ return 1; } SSL *ossl_quic_channel_get0_ssl(QUIC_CHANNEL *ch) { return ch->tls; }