Coverage Report

Created: 2025-06-13 06:55

/src/openssl/ssl/quic/quic_statm.c
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Source (jump to first uncovered line)
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/*
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 * Copyright 2022-2023 The OpenSSL Project Authors. All Rights Reserved.
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 *
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 * Licensed under the Apache License 2.0 (the "License").  You may not use
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 * this file except in compliance with the License.  You can obtain a copy
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 * in the file LICENSE in the source distribution or at
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 * https://www.openssl.org/source/license.html
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 */
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#include "internal/quic_statm.h"
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void ossl_statm_update_rtt(OSSL_STATM *statm,
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                           OSSL_TIME ack_delay,
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                           OSSL_TIME override_latest_rtt)
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0
{
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    OSSL_TIME adjusted_rtt, latest_rtt = override_latest_rtt;
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    /* Use provided RTT value, or else last RTT value. */
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    if (ossl_time_is_zero(latest_rtt))
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        latest_rtt = statm->latest_rtt;
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    else
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        statm->latest_rtt = latest_rtt;
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    if (!statm->have_first_sample) {
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        statm->min_rtt              = latest_rtt;
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        statm->smoothed_rtt         = latest_rtt;
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        statm->rtt_variance         = ossl_time_divide(latest_rtt, 2);
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        statm->have_first_sample    = 1;
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        return;
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    }
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    /* Update minimum RTT. */
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    if (ossl_time_compare(latest_rtt, statm->min_rtt) < 0)
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        statm->min_rtt = latest_rtt;
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    /*
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     * Enforcement of max_ack_delay is the responsibility of
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     * the caller as it is context-dependent.
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     */
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    adjusted_rtt = latest_rtt;
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    if (ossl_time_compare(latest_rtt, ossl_time_add(statm->min_rtt, ack_delay)) >= 0)
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        adjusted_rtt = ossl_time_subtract(latest_rtt, ack_delay);
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    statm->rtt_variance = ossl_time_divide(ossl_time_add(ossl_time_multiply(statm->rtt_variance, 3),
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                                                         ossl_time_abs_difference(statm->smoothed_rtt,
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                                                                              adjusted_rtt)), 4);
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    statm->smoothed_rtt = ossl_time_divide(ossl_time_add(ossl_time_multiply(statm->smoothed_rtt, 7),
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                                                         adjusted_rtt), 8);
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}
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/* RFC 9002 kInitialRtt value. RFC recommended value. */
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#define K_INITIAL_RTT               ossl_ms2time(333)
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int ossl_statm_init(OSSL_STATM *statm)
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0
{
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    statm->smoothed_rtt             = K_INITIAL_RTT;
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    statm->latest_rtt               = ossl_time_zero();
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    statm->min_rtt                  = ossl_time_infinite();
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    statm->rtt_variance             = ossl_time_divide(K_INITIAL_RTT, 2);
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    statm->have_first_sample        = 0;
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    return 1;
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}
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void ossl_statm_destroy(OSSL_STATM *statm)
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{
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    /* No-op. */
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0
}
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void ossl_statm_get_rtt_info(OSSL_STATM *statm, OSSL_RTT_INFO *rtt_info)
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{
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    rtt_info->min_rtt           = statm->min_rtt;
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    rtt_info->latest_rtt        = statm->latest_rtt;
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    rtt_info->smoothed_rtt      = statm->smoothed_rtt;
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    rtt_info->rtt_variance      = statm->rtt_variance;
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}