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-rw-r--r--src/h2load_quic.cc790
1 files changed, 790 insertions, 0 deletions
diff --git a/src/h2load_quic.cc b/src/h2load_quic.cc
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+++ b/src/h2load_quic.cc
@@ -0,0 +1,790 @@
+/*
+ * nghttp2 - HTTP/2 C Library
+ *
+ * Copyright (c) 2019 nghttp2 contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include "h2load_quic.h"
+
+#include <netinet/udp.h>
+
+#include <iostream>
+
+#ifdef HAVE_LIBNGTCP2_CRYPTO_OPENSSL
+# include <ngtcp2/ngtcp2_crypto_openssl.h>
+#endif // HAVE_LIBNGTCP2_CRYPTO_OPENSSL
+#ifdef HAVE_LIBNGTCP2_CRYPTO_BORINGSSL
+# include <ngtcp2/ngtcp2_crypto_boringssl.h>
+#endif // HAVE_LIBNGTCP2_CRYPTO_BORINGSSL
+
+#include <openssl/err.h>
+#include <openssl/rand.h>
+
+#include "h2load_http3_session.h"
+
+namespace h2load {
+
+namespace {
+int handshake_completed(ngtcp2_conn *conn, void *user_data) {
+ auto c = static_cast<Client *>(user_data);
+
+ if (c->quic_handshake_completed() != 0) {
+ return NGTCP2_ERR_CALLBACK_FAILURE;
+ }
+
+ return 0;
+}
+} // namespace
+
+int Client::quic_handshake_completed() { return connection_made(); }
+
+namespace {
+int recv_stream_data(ngtcp2_conn *conn, uint32_t flags, int64_t stream_id,
+ uint64_t offset, const uint8_t *data, size_t datalen,
+ void *user_data, void *stream_user_data) {
+ auto c = static_cast<Client *>(user_data);
+ if (c->quic_recv_stream_data(flags, stream_id, data, datalen) != 0) {
+ // TODO Better to do this gracefully rather than
+ // NGTCP2_ERR_CALLBACK_FAILURE. Perhaps, call
+ // ngtcp2_conn_write_application_close() ?
+ return NGTCP2_ERR_CALLBACK_FAILURE;
+ }
+ return 0;
+}
+} // namespace
+
+int Client::quic_recv_stream_data(uint32_t flags, int64_t stream_id,
+ const uint8_t *data, size_t datalen) {
+ if (worker->current_phase == Phase::MAIN_DURATION) {
+ worker->stats.bytes_total += datalen;
+ }
+
+ auto s = static_cast<Http3Session *>(session.get());
+ auto nconsumed = s->read_stream(flags, stream_id, data, datalen);
+ if (nconsumed == -1) {
+ return -1;
+ }
+
+ ngtcp2_conn_extend_max_stream_offset(quic.conn, stream_id, nconsumed);
+ ngtcp2_conn_extend_max_offset(quic.conn, nconsumed);
+
+ return 0;
+}
+
+namespace {
+int acked_stream_data_offset(ngtcp2_conn *conn, int64_t stream_id,
+ uint64_t offset, uint64_t datalen, void *user_data,
+ void *stream_user_data) {
+ auto c = static_cast<Client *>(user_data);
+ if (c->quic_acked_stream_data_offset(stream_id, datalen) != 0) {
+ return NGTCP2_ERR_CALLBACK_FAILURE;
+ }
+ return 0;
+}
+} // namespace
+
+int Client::quic_acked_stream_data_offset(int64_t stream_id, size_t datalen) {
+ auto s = static_cast<Http3Session *>(session.get());
+ if (s->add_ack_offset(stream_id, datalen) != 0) {
+ return -1;
+ }
+ return 0;
+}
+
+namespace {
+int stream_close(ngtcp2_conn *conn, uint32_t flags, int64_t stream_id,
+ uint64_t app_error_code, void *user_data,
+ void *stream_user_data) {
+ auto c = static_cast<Client *>(user_data);
+
+ if (!(flags & NGTCP2_STREAM_CLOSE_FLAG_APP_ERROR_CODE_SET)) {
+ app_error_code = NGHTTP3_H3_NO_ERROR;
+ }
+
+ if (c->quic_stream_close(stream_id, app_error_code) != 0) {
+ return NGTCP2_ERR_CALLBACK_FAILURE;
+ }
+ return 0;
+}
+} // namespace
+
+int Client::quic_stream_close(int64_t stream_id, uint64_t app_error_code) {
+ auto s = static_cast<Http3Session *>(session.get());
+ if (s->close_stream(stream_id, app_error_code) != 0) {
+ return -1;
+ }
+ return 0;
+}
+
+namespace {
+int stream_reset(ngtcp2_conn *conn, int64_t stream_id, uint64_t final_size,
+ uint64_t app_error_code, void *user_data,
+ void *stream_user_data) {
+ auto c = static_cast<Client *>(user_data);
+ if (c->quic_stream_reset(stream_id, app_error_code) != 0) {
+ return NGTCP2_ERR_CALLBACK_FAILURE;
+ }
+ return 0;
+}
+} // namespace
+
+int Client::quic_stream_reset(int64_t stream_id, uint64_t app_error_code) {
+ auto s = static_cast<Http3Session *>(session.get());
+ if (s->shutdown_stream_read(stream_id) != 0) {
+ return -1;
+ }
+ return 0;
+}
+
+namespace {
+int stream_stop_sending(ngtcp2_conn *conn, int64_t stream_id,
+ uint64_t app_error_code, void *user_data,
+ void *stream_user_data) {
+ auto c = static_cast<Client *>(user_data);
+ if (c->quic_stream_stop_sending(stream_id, app_error_code) != 0) {
+ return NGTCP2_ERR_CALLBACK_FAILURE;
+ }
+ return 0;
+}
+} // namespace
+
+int Client::quic_stream_stop_sending(int64_t stream_id,
+ uint64_t app_error_code) {
+ auto s = static_cast<Http3Session *>(session.get());
+ if (s->shutdown_stream_read(stream_id) != 0) {
+ return -1;
+ }
+ return 0;
+}
+
+namespace {
+int extend_max_local_streams_bidi(ngtcp2_conn *conn, uint64_t max_streams,
+ void *user_data) {
+ auto c = static_cast<Client *>(user_data);
+
+ if (c->quic_extend_max_local_streams() != 0) {
+ return NGTCP2_ERR_CALLBACK_FAILURE;
+ }
+
+ return 0;
+}
+} // namespace
+
+int Client::quic_extend_max_local_streams() {
+ auto s = static_cast<Http3Session *>(session.get());
+ if (s->extend_max_local_streams() != 0) {
+ return NGTCP2_ERR_CALLBACK_FAILURE;
+ }
+ return 0;
+}
+
+namespace {
+int get_new_connection_id(ngtcp2_conn *conn, ngtcp2_cid *cid, uint8_t *token,
+ size_t cidlen, void *user_data) {
+ if (RAND_bytes(cid->data, cidlen) != 1) {
+ return NGTCP2_ERR_CALLBACK_FAILURE;
+ }
+
+ cid->datalen = cidlen;
+
+ if (RAND_bytes(token, NGTCP2_STATELESS_RESET_TOKENLEN) != 1) {
+ return NGTCP2_ERR_CALLBACK_FAILURE;
+ }
+
+ return 0;
+}
+} // namespace
+
+namespace {
+void debug_log_printf(void *user_data, const char *fmt, ...) {
+ va_list ap;
+
+ va_start(ap, fmt);
+ vfprintf(stderr, fmt, ap);
+ va_end(ap);
+
+ fprintf(stderr, "\n");
+}
+} // namespace
+
+namespace {
+int generate_cid(ngtcp2_cid &dest) {
+ dest.datalen = 8;
+
+ if (RAND_bytes(dest.data, dest.datalen) != 1) {
+ return -1;
+ }
+
+ return 0;
+}
+} // namespace
+
+namespace {
+ngtcp2_tstamp timestamp(struct ev_loop *loop) {
+ return ev_now(loop) * NGTCP2_SECONDS;
+}
+} // namespace
+
+// qlog write callback -- excerpted from ngtcp2/examples/client_base.cc
+namespace {
+void qlog_write_cb(void *user_data, uint32_t flags, const void *data,
+ size_t datalen) {
+ auto c = static_cast<Client *>(user_data);
+ c->quic_write_qlog(data, datalen);
+}
+} // namespace
+
+void Client::quic_write_qlog(const void *data, size_t datalen) {
+ assert(quic.qlog_file != nullptr);
+ fwrite(data, 1, datalen, quic.qlog_file);
+}
+
+namespace {
+void rand(uint8_t *dest, size_t destlen, const ngtcp2_rand_ctx *rand_ctx) {
+ util::random_bytes(dest, dest + destlen,
+ *static_cast<std::mt19937 *>(rand_ctx->native_handle));
+}
+} // namespace
+
+namespace {
+int recv_rx_key(ngtcp2_conn *conn, ngtcp2_crypto_level level, void *user_data) {
+ if (level != NGTCP2_CRYPTO_LEVEL_APPLICATION) {
+ return 0;
+ }
+
+ auto c = static_cast<Client *>(user_data);
+
+ if (c->quic_make_http3_session() != 0) {
+ return NGTCP2_ERR_CALLBACK_FAILURE;
+ }
+
+ return 0;
+}
+} // namespace
+
+int Client::quic_make_http3_session() {
+ auto s = std::make_unique<Http3Session>(this);
+ if (s->init_conn() == -1) {
+ return -1;
+ }
+ session = std::move(s);
+
+ return 0;
+}
+
+namespace {
+ngtcp2_conn *get_conn(ngtcp2_crypto_conn_ref *conn_ref) {
+ auto c = static_cast<Client *>(conn_ref->user_data);
+ return c->quic.conn;
+}
+} // namespace
+
+int Client::quic_init(const sockaddr *local_addr, socklen_t local_addrlen,
+ const sockaddr *remote_addr, socklen_t remote_addrlen) {
+ int rv;
+
+ if (!ssl) {
+ ssl = SSL_new(worker->ssl_ctx);
+
+ quic.conn_ref.get_conn = get_conn;
+ quic.conn_ref.user_data = this;
+
+ SSL_set_app_data(ssl, &quic.conn_ref);
+ SSL_set_connect_state(ssl);
+ SSL_set_quic_use_legacy_codepoint(ssl, 0);
+ }
+
+ auto callbacks = ngtcp2_callbacks{
+ ngtcp2_crypto_client_initial_cb,
+ nullptr, // recv_client_initial
+ ngtcp2_crypto_recv_crypto_data_cb,
+ h2load::handshake_completed,
+ nullptr, // recv_version_negotiation
+ ngtcp2_crypto_encrypt_cb,
+ ngtcp2_crypto_decrypt_cb,
+ ngtcp2_crypto_hp_mask_cb,
+ h2load::recv_stream_data,
+ h2load::acked_stream_data_offset,
+ nullptr, // stream_open
+ h2load::stream_close,
+ nullptr, // recv_stateless_reset
+ ngtcp2_crypto_recv_retry_cb,
+ h2load::extend_max_local_streams_bidi,
+ nullptr, // extend_max_local_streams_uni
+ h2load::rand,
+ get_new_connection_id,
+ nullptr, // remove_connection_id
+ ngtcp2_crypto_update_key_cb,
+ nullptr, // path_validation
+ nullptr, // select_preferred_addr
+ h2load::stream_reset,
+ nullptr, // extend_max_remote_streams_bidi
+ nullptr, // extend_max_remote_streams_uni
+ nullptr, // extend_max_stream_data
+ nullptr, // dcid_status
+ nullptr, // handshake_confirmed
+ nullptr, // recv_new_token
+ ngtcp2_crypto_delete_crypto_aead_ctx_cb,
+ ngtcp2_crypto_delete_crypto_cipher_ctx_cb,
+ nullptr, // recv_datagram
+ nullptr, // ack_datagram
+ nullptr, // lost_datagram
+ ngtcp2_crypto_get_path_challenge_data_cb,
+ h2load::stream_stop_sending,
+ nullptr, // version_negotiation
+ h2load::recv_rx_key,
+ nullptr, // recv_tx_key
+ };
+
+ ngtcp2_cid scid, dcid;
+ if (generate_cid(scid) != 0) {
+ return -1;
+ }
+ if (generate_cid(dcid) != 0) {
+ return -1;
+ }
+
+ auto config = worker->config;
+
+ ngtcp2_settings settings;
+ ngtcp2_settings_default(&settings);
+ if (config->verbose) {
+ settings.log_printf = debug_log_printf;
+ }
+ settings.initial_ts = timestamp(worker->loop);
+ settings.rand_ctx.native_handle = &worker->randgen;
+ if (!config->qlog_file_base.empty()) {
+ assert(quic.qlog_file == nullptr);
+ auto path = config->qlog_file_base;
+ path += '.';
+ path += util::utos(worker->id);
+ path += '.';
+ path += util::utos(id);
+ path += ".sqlog";
+ quic.qlog_file = fopen(path.c_str(), "w");
+ if (quic.qlog_file == nullptr) {
+ std::cerr << "Failed to open a qlog file: " << path << std::endl;
+ return -1;
+ }
+ settings.qlog.write = qlog_write_cb;
+ }
+ if (config->max_udp_payload_size) {
+ settings.max_tx_udp_payload_size = config->max_udp_payload_size;
+ settings.no_tx_udp_payload_size_shaping = 1;
+ }
+
+ ngtcp2_transport_params params;
+ ngtcp2_transport_params_default(&params);
+ auto max_stream_data =
+ std::min((1 << 26) - 1, (1 << config->window_bits) - 1);
+ params.initial_max_stream_data_bidi_local = max_stream_data;
+ params.initial_max_stream_data_uni = max_stream_data;
+ params.initial_max_data = (1 << config->connection_window_bits) - 1;
+ params.initial_max_streams_bidi = 0;
+ params.initial_max_streams_uni = 100;
+ params.max_idle_timeout = 30 * NGTCP2_SECONDS;
+
+ auto path = ngtcp2_path{
+ {
+ const_cast<sockaddr *>(local_addr),
+ local_addrlen,
+ },
+ {
+ const_cast<sockaddr *>(remote_addr),
+ remote_addrlen,
+ },
+ };
+
+ assert(config->npn_list.size());
+
+ uint32_t quic_version;
+
+ if (config->npn_list[0] == NGHTTP3_ALPN_H3) {
+ quic_version = NGTCP2_PROTO_VER_V1;
+ } else {
+ quic_version = NGTCP2_PROTO_VER_MIN;
+ }
+
+ rv = ngtcp2_conn_client_new(&quic.conn, &dcid, &scid, &path, quic_version,
+ &callbacks, &settings, &params, nullptr, this);
+ if (rv != 0) {
+ return -1;
+ }
+
+ ngtcp2_conn_set_tls_native_handle(quic.conn, ssl);
+
+ return 0;
+}
+
+void Client::quic_free() {
+ ngtcp2_conn_del(quic.conn);
+ if (quic.qlog_file != nullptr) {
+ fclose(quic.qlog_file);
+ quic.qlog_file = nullptr;
+ }
+}
+
+void Client::quic_close_connection() {
+ if (!quic.conn) {
+ return;
+ }
+
+ std::array<uint8_t, NGTCP2_MAX_UDP_PAYLOAD_SIZE> buf;
+ ngtcp2_path_storage ps;
+ ngtcp2_path_storage_zero(&ps);
+
+ auto nwrite = ngtcp2_conn_write_connection_close(
+ quic.conn, &ps.path, nullptr, buf.data(), buf.size(), &quic.last_error,
+ timestamp(worker->loop));
+
+ if (nwrite <= 0) {
+ return;
+ }
+
+ write_udp(reinterpret_cast<sockaddr *>(ps.path.remote.addr),
+ ps.path.remote.addrlen, buf.data(), nwrite, 0);
+}
+
+int Client::quic_write_client_handshake(ngtcp2_crypto_level level,
+ const uint8_t *data, size_t datalen) {
+ int rv;
+
+ assert(level < 2);
+
+ rv = ngtcp2_conn_submit_crypto_data(quic.conn, level, data, datalen);
+ if (rv != 0) {
+ std::cerr << "ngtcp2_conn_submit_crypto_data: " << ngtcp2_strerror(rv)
+ << std::endl;
+ return -1;
+ }
+
+ return 0;
+}
+
+void quic_pkt_timeout_cb(struct ev_loop *loop, ev_timer *w, int revents) {
+ auto c = static_cast<Client *>(w->data);
+
+ if (c->quic_pkt_timeout() != 0) {
+ c->fail();
+ c->worker->free_client(c);
+ delete c;
+ return;
+ }
+}
+
+int Client::quic_pkt_timeout() {
+ int rv;
+ auto now = timestamp(worker->loop);
+
+ rv = ngtcp2_conn_handle_expiry(quic.conn, now);
+ if (rv != 0) {
+ ngtcp2_connection_close_error_set_transport_error_liberr(&quic.last_error,
+ rv, nullptr, 0);
+ return -1;
+ }
+
+ return write_quic();
+}
+
+void Client::quic_restart_pkt_timer() {
+ auto expiry = ngtcp2_conn_get_expiry(quic.conn);
+ auto now = timestamp(worker->loop);
+ auto t = expiry > now ? static_cast<ev_tstamp>(expiry - now) / NGTCP2_SECONDS
+ : 1e-9;
+ quic.pkt_timer.repeat = t;
+ ev_timer_again(worker->loop, &quic.pkt_timer);
+}
+
+int Client::read_quic() {
+ std::array<uint8_t, 65536> buf;
+ sockaddr_union su;
+ socklen_t addrlen = sizeof(su);
+ int rv;
+ size_t pktcnt = 0;
+ ngtcp2_pkt_info pi{};
+
+ for (;;) {
+ auto nread =
+ recvfrom(fd, buf.data(), buf.size(), MSG_DONTWAIT, &su.sa, &addrlen);
+ if (nread == -1) {
+ return 0;
+ }
+
+ assert(quic.conn);
+
+ ++worker->stats.udp_dgram_recv;
+
+ auto path = ngtcp2_path{
+ {
+ &local_addr.su.sa,
+ static_cast<socklen_t>(local_addr.len),
+ },
+ {
+ &su.sa,
+ addrlen,
+ },
+ };
+
+ rv = ngtcp2_conn_read_pkt(quic.conn, &path, &pi, buf.data(), nread,
+ timestamp(worker->loop));
+ if (rv != 0) {
+ std::cerr << "ngtcp2_conn_read_pkt: " << ngtcp2_strerror(rv) << std::endl;
+
+ if (!quic.last_error.error_code) {
+ if (rv == NGTCP2_ERR_CRYPTO) {
+ ngtcp2_connection_close_error_set_transport_error_tls_alert(
+ &quic.last_error, ngtcp2_conn_get_tls_alert(quic.conn), nullptr,
+ 0);
+ } else {
+ ngtcp2_connection_close_error_set_transport_error_liberr(
+ &quic.last_error, rv, nullptr, 0);
+ }
+ }
+
+ return -1;
+ }
+
+ if (++pktcnt == 100) {
+ break;
+ }
+ }
+
+ return 0;
+}
+
+int Client::write_quic() {
+ int rv;
+
+ ev_io_stop(worker->loop, &wev);
+
+ if (quic.close_requested) {
+ return -1;
+ }
+
+ if (quic.tx.send_blocked) {
+ rv = send_blocked_packet();
+ if (rv != 0) {
+ return -1;
+ }
+
+ if (quic.tx.send_blocked) {
+ return 0;
+ }
+ }
+
+ std::array<nghttp3_vec, 16> vec;
+ size_t pktcnt = 0;
+ auto max_udp_payload_size =
+ ngtcp2_conn_get_max_tx_udp_payload_size(quic.conn);
+#ifdef UDP_SEGMENT
+ auto path_max_udp_payload_size =
+ ngtcp2_conn_get_path_max_tx_udp_payload_size(quic.conn);
+#endif // UDP_SEGMENT
+ auto max_pktcnt =
+ ngtcp2_conn_get_send_quantum(quic.conn) / max_udp_payload_size;
+ uint8_t *bufpos = quic.tx.data.get();
+ ngtcp2_path_storage ps;
+ size_t gso_size = 0;
+
+ ngtcp2_path_storage_zero(&ps);
+
+ auto s = static_cast<Http3Session *>(session.get());
+
+ for (;;) {
+ int64_t stream_id = -1;
+ int fin = 0;
+ ssize_t sveccnt = 0;
+
+ if (session && ngtcp2_conn_get_max_data_left(quic.conn)) {
+ sveccnt = s->write_stream(stream_id, fin, vec.data(), vec.size());
+ if (sveccnt == -1) {
+ return -1;
+ }
+ }
+
+ ngtcp2_ssize ndatalen;
+ auto v = vec.data();
+ auto vcnt = static_cast<size_t>(sveccnt);
+
+ uint32_t flags = NGTCP2_WRITE_STREAM_FLAG_MORE;
+ if (fin) {
+ flags |= NGTCP2_WRITE_STREAM_FLAG_FIN;
+ }
+
+ auto nwrite = ngtcp2_conn_writev_stream(
+ quic.conn, &ps.path, nullptr, bufpos, max_udp_payload_size, &ndatalen,
+ flags, stream_id, reinterpret_cast<const ngtcp2_vec *>(v), vcnt,
+ timestamp(worker->loop));
+ if (nwrite < 0) {
+ switch (nwrite) {
+ case NGTCP2_ERR_STREAM_DATA_BLOCKED:
+ assert(ndatalen == -1);
+ s->block_stream(stream_id);
+ continue;
+ case NGTCP2_ERR_STREAM_SHUT_WR:
+ assert(ndatalen == -1);
+ s->shutdown_stream_write(stream_id);
+ continue;
+ case NGTCP2_ERR_WRITE_MORE:
+ assert(ndatalen >= 0);
+ if (s->add_write_offset(stream_id, ndatalen) != 0) {
+ return -1;
+ }
+ continue;
+ }
+
+ ngtcp2_connection_close_error_set_transport_error_liberr(
+ &quic.last_error, nwrite, nullptr, 0);
+ return -1;
+ } else if (ndatalen >= 0 && s->add_write_offset(stream_id, ndatalen) != 0) {
+ return -1;
+ }
+
+ quic_restart_pkt_timer();
+
+ if (nwrite == 0) {
+ if (bufpos - quic.tx.data.get()) {
+ auto data = quic.tx.data.get();
+ auto datalen = bufpos - quic.tx.data.get();
+ rv = write_udp(ps.path.remote.addr, ps.path.remote.addrlen, data,
+ datalen, gso_size);
+ if (rv == 1) {
+ on_send_blocked(ps.path.remote, data, datalen, gso_size);
+ signal_write();
+ return 0;
+ }
+ }
+ return 0;
+ }
+
+ bufpos += nwrite;
+
+#ifdef UDP_SEGMENT
+ if (worker->config->no_udp_gso) {
+#endif // UDP_SEGMENT
+ auto data = quic.tx.data.get();
+ auto datalen = bufpos - quic.tx.data.get();
+ rv = write_udp(ps.path.remote.addr, ps.path.remote.addrlen, data, datalen,
+ 0);
+ if (rv == 1) {
+ on_send_blocked(ps.path.remote, data, datalen, 0);
+ signal_write();
+ return 0;
+ }
+
+ if (++pktcnt == max_pktcnt) {
+ signal_write();
+ return 0;
+ }
+
+ bufpos = quic.tx.data.get();
+
+#ifdef UDP_SEGMENT
+ continue;
+ }
+#endif // UDP_SEGMENT
+
+#ifdef UDP_SEGMENT
+ if (pktcnt == 0) {
+ gso_size = nwrite;
+ } else if (static_cast<size_t>(nwrite) > gso_size ||
+ (gso_size > path_max_udp_payload_size &&
+ static_cast<size_t>(nwrite) != gso_size)) {
+ auto data = quic.tx.data.get();
+ auto datalen = bufpos - quic.tx.data.get() - nwrite;
+ rv = write_udp(ps.path.remote.addr, ps.path.remote.addrlen, data, datalen,
+ gso_size);
+ if (rv == 1) {
+ on_send_blocked(ps.path.remote, data, datalen, gso_size);
+ on_send_blocked(ps.path.remote, bufpos - nwrite, nwrite, 0);
+ } else {
+ auto data = bufpos - nwrite;
+ rv = write_udp(ps.path.remote.addr, ps.path.remote.addrlen, data,
+ nwrite, 0);
+ if (rv == 1) {
+ on_send_blocked(ps.path.remote, data, nwrite, 0);
+ }
+ }
+
+ signal_write();
+ return 0;
+ }
+
+ // Assume that the path does not change.
+ if (++pktcnt == max_pktcnt || static_cast<size_t>(nwrite) < gso_size) {
+ auto data = quic.tx.data.get();
+ auto datalen = bufpos - quic.tx.data.get();
+ rv = write_udp(ps.path.remote.addr, ps.path.remote.addrlen, data, datalen,
+ gso_size);
+ if (rv == 1) {
+ on_send_blocked(ps.path.remote, data, datalen, gso_size);
+ }
+ signal_write();
+ return 0;
+ }
+#endif // UDP_SEGMENT
+ }
+}
+
+void Client::on_send_blocked(const ngtcp2_addr &remote_addr,
+ const uint8_t *data, size_t datalen,
+ size_t gso_size) {
+ assert(quic.tx.num_blocked || !quic.tx.send_blocked);
+ assert(quic.tx.num_blocked < 2);
+
+ quic.tx.send_blocked = true;
+
+ auto &p = quic.tx.blocked[quic.tx.num_blocked++];
+
+ memcpy(&p.remote_addr.su, remote_addr.addr, remote_addr.addrlen);
+
+ p.remote_addr.len = remote_addr.addrlen;
+ p.data = data;
+ p.datalen = datalen;
+ p.gso_size = gso_size;
+}
+
+int Client::send_blocked_packet() {
+ int rv;
+
+ assert(quic.tx.send_blocked);
+
+ for (; quic.tx.num_blocked_sent < quic.tx.num_blocked;
+ ++quic.tx.num_blocked_sent) {
+ auto &p = quic.tx.blocked[quic.tx.num_blocked_sent];
+
+ rv = write_udp(&p.remote_addr.su.sa, p.remote_addr.len, p.data, p.datalen,
+ p.gso_size);
+ if (rv == 1) {
+ signal_write();
+
+ return 0;
+ }
+ }
+
+ quic.tx.send_blocked = false;
+ quic.tx.num_blocked = 0;
+ quic.tx.num_blocked_sent = 0;
+
+ return 0;
+}
+
+} // namespace h2load