<!--
Copyright 2020 The Chromium Authors
Use of this source code is governed by a BSD-style license that can be
found in the LICENSE file.
-->

<!--
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along with a detailed description for each histogram.

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Please follow the instructions in the OWNERS file in this directory to find a
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<histogram-configuration>

<histograms>

<histogram name="Security.ClientAuth.CertificateSelectionSource"
    enum="ClientCertSelectionResult" expires_after="2020-08-16">
  <owner>jdeblasio@chromium.org</owner>
  <summary>
    When TLS client authentication is requested by the server, Chrome must
    choose whether to return a certificate or to abort the handshake. This
    histogram records how this determination was made, either as a result of
    user action, or as chosen automatically due to content settings. It only
    records when a fresh certificate selection would be attempted (and thus
    ignores cache hits). This histogram is recorded in SSLClientAuthObserver for
    user-selected outcomes and in ChromeContentBrowserClient for policy
    outcomes. This histogram does not cover mobile, as certificate handling is
    not handled by Chrome on Android nor iOS.
  </summary>
</histogram>

<histogram name="Security.DataDecoder.Image.DecodingTime" units="ms"
    expires_after="2023-07-16">
  <owner>lukasza@chromium.org</owner>
  <owner>rsesek@chromium.org</owner>
  <summary>
    Logged once for every invocation of `data_decoder::DecodeImage` and/or
    `data_decoder::DecodeImageIsolated`. Logs the time that has elapsed while
    decoding the image (typically this happens in the Utility process). The time
    is recorded in all the cases (including empty input which don't require
    actual image decoding).
  </summary>
</histogram>

<histogram name="Security.DataDecoder.Image.Isolated.EndToEndTime" units="ms"
    expires_after="2023-04-23">
  <owner>lukasza@chromium.org</owner>
  <owner>rsesek@chromium.org</owner>
  <summary>
    Logged once for every invocation of `data_decoder::DecodeImageIsolated`.
    Logs the time that has elapsed between 1) invocation of DecodeImageIsolated
    and 2) calling the completion callback (both of these events happen in the
    Browser process). The elapsed time covers A) spawning the utility process,
    B) decoding the image, C) IPC overhead.

    Note that there are 2 sets of similar metrics:
    Security.DataDecoder.Image.Isolated. and
    Security.DataDecoder.Image.Reusable. In the Isolated case a Utility process
    is spawned for each image decoding operation and the ...End2End and
    ...ProcessOverhead metrics always include process spawning overhead. In the
    Reusable case a Utility process may get reused when decoding a batch of
    images, and the ...End2End and ...ProcessOverhead metrics may or may not
    include process spawning overhead (the process will only need to be spawned
    for the first image in a batch + after the process has been shut down due to
    inactivity).
  </summary>
</histogram>

<histogram name="Security.DataDecoder.Image.Isolated.ProcessOverhead"
    units="ms" expires_after="2023-08-27">
  <owner>lukasza@chromium.org</owner>
  <owner>rsesek@chromium.org</owner>
  <summary>
    Logged once for every invocation of `data_decoder::DecodeImageIsolated`.
    Logs the overhead of using a separate process for decoding the images by
    calculating the difference between ...Image.Isolated.EndToEndTime and the
    ...Image.DecodingTime metrics.

    Note that there are 2 sets of similar metrics:
    Security.DataDecoder.Image.Isolated. and
    Security.DataDecoder.Image.Reusable. In the Isolated case a Utility process
    is spawned for each image decoding operation and the ...End2End and
    ...ProcessOverhead metrics always include process spawning overhead. In the
    Reusable case a Utility process may get reused when decoding a batch of
    images, and the ...End2End and ...ProcessOverhead metrics may or may not
    include process spawning overhead (the process will only need to be spawned
    for the first image in a batch + after the process has been shut down due to
    inactivity).
  </summary>
</histogram>

<histogram name="Security.DataDecoder.Image.Reusable.EndToEndTime" units="ms"
    expires_after="2023-04-23">
  <owner>lukasza@chromium.org</owner>
  <owner>rsesek@chromium.org</owner>
  <summary>
    Logged once for every invocation of `data_decoder::DecodeImage`. Logs the
    time that has elapsed between 1) invocation of DecodeImage and 2) calling
    the completion callback (both of these events happen in the Browser
    process). The elapsed time covers A) spawning the utility process (if
    needed), B) decoding the image, C) IPC overhead.

    Note that there are 2 sets of similar metrics:
    Security.DataDecoder.Image.Isolated. and
    Security.DataDecoder.Image.Reusable. In the Isolated case a Utility process
    is spawned for each image decoding operation and the ...End2End and
    ...ProcessOverhead metrics always include process spawning overhead. In the
    Reusable case a Utility process may get reused when decoding a batch of
    images, and the ...End2End and ...ProcessOverhead metrics may or may not
    include process spawning overhead (the process will only need to be spawned
    for the first image in a batch + after the process has been shut down due to
    inactivity).
  </summary>
</histogram>

<histogram name="Security.DataDecoder.Image.Reusable.ProcessOverhead"
    units="ms" expires_after="2023-08-27">
  <owner>lukasza@chromium.org</owner>
  <owner>rsesek@chromium.org</owner>
  <summary>
    Logged once for every invocation of `data_decoder::DecodeImage`. Logs the
    overhead of using a separate process for decoding the images by calculating
    the difference between ...Image.Reusable.EndToEndTime and the
    ...Image.DecodingTime metrics.

    Note that there are 2 sets of similar metrics:
    Security.DataDecoder.Image.Isolated. and
    Security.DataDecoder.Image.Reusable. In the Isolated case a Utility process
    is spawned for each image decoding operation and the ...End2End and
    ...ProcessOverhead metrics always include process spawning overhead. In the
    Reusable case a Utility process may get reused when decoding a batch of
    images, and the ...End2End and ...ProcessOverhead metrics may or may not
    include process spawning overhead (the process will only need to be spawned
    for the first image in a batch + after the process has been shut down due to
    inactivity).
  </summary>
</histogram>

<histogram name="Security.GwpAsan.CrashAnalysisResult.{Allocator}"
    enum="GwpAsanCrashAnalysisResult" expires_after="2023-09-27">
  <owner>glazunov@google.com</owner>
  <owner>mpdenton@chromium.org</owner>
  <owner>chrome-memory-tok@google.com</owner>
  <summary>
    Reports the GWP-ASan crash analysis result. That can either be a
    determination that the crash was related to GWP-ASan, not related to
    GWP-ASan, or an error making that determination. Recorded with every crash.
  </summary>
  <token key="Allocator">
    <variant name="Malloc"/>
    <variant name="PartitionAlloc"/>
  </token>
</histogram>

<histogram name="Security.HttpsFirstMode.NavigationEvent"
    enum="HttpsFirstModeNavigationEvent" expires_after="2023-09-10">
  <owner>cthomp@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Events for navigations that are upgraded from HTTP to HTTPS by HTTPS-First
    Mode. Recorded for eligible navigations (HTTP main frame navigations that
    are not allowlisted), if the profile is opted in to HTTPS-First Mode.
  </summary>
</histogram>

<histogram name="Security.HttpsFirstMode.SettingChanged" enum="BooleanEnabled"
    expires_after="2023-09-10">
  <owner>cthomp@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records the HTTPS-First Mode preference state when it changes for a profile.
    Recorded for regular profiles only (not for Incognito, Guest, or Sign-in
    profiles).
  </summary>
</histogram>

<histogram name="Security.HttpsFirstMode.SettingEnabledAtStartup"
    enum="BooleanEnabled" expires_after="2023-09-10">
  <owner>cthomp@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records whether the HTTPS-First Mode preference is enabled at profile
    startup. Recorded for regular profiles only (not for Incognito, Guest, or
    Sign-in profiles).
  </summary>
</histogram>

<histogram
    name="Security.HttpsFirstModeWithEngagementHeuristic.AccumulatedHostCount"
    units="hostnames" expires_after="2023-09-10">
  <owner>meacer@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records the accumulated number of host that have HFM enabled at some point
    due to the site engagement heuristic. Includes hosts that have HTTP allowed.
    Recorded at the time of navigation when HFM upgrades trigger.
  </summary>
</histogram>

<histogram name="Security.HttpsFirstModeWithEngagementHeuristic.Duration"
    units="seconds" expires_after="2023-09-10">
  <owner>meacer@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records the duration a host has HFM enabled due to the site engagement
    heuristic. Only recorded for hosts removed from the HFM list. Recorded at
    the time of navigation when HFM upgrades trigger.
  </summary>
</histogram>

<histogram name="Security.HttpsFirstModeWithEngagementHeuristic.HostCount"
    units="hostnames" expires_after="2023-09-10">
  <owner>meacer@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records the current number of host that have HFM enabled due to the site
    engagement heuristic. Includes hosts that have HTTP allowed. Recorded at the
    time of navigation when HFM upgrades trigger.
  </summary>
</histogram>

<histogram
    name="Security.HttpsFirstModeWithEngagementHeuristic.NavigationEvent"
    enum="HttpsFirstModeNavigationEvent" expires_after="2023-09-10">
  <owner>meacer@chromium.org</owner>
  <owner>cthomp@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Same as Security.HttpsFirstMode.NavigationEvent but only recorded iff HFM is
    disabled by the UI setting and enabled by the Site Engagement Heuristic
    because the site's HTTPS score is high and HTTP score is low.
  </summary>
</histogram>

<histogram name="Security.HttpsFirstModeWithEngagementHeuristic.State"
    enum="SiteEngagementHeuristicState" expires_after="2023-09-10">
  <owner>meacer@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records whether the HTTPS-First Mode got enabled or disabled on a site due
    to its HTTP and HTTPS site engagement scores. Only recorded if the enabled
    state changes. Recorded even for sites allowlisted to load over HTTP.
  </summary>
</histogram>

<histogram name="Security.JSONParser.ChromiumExtensionUsage"
    enum="JsonParserExtension" expires_after="2023-09-10">
  <owner>rsesek@chromium.org</owner>
  <owner>chrome-platform-security@google.com</owner>
  <summary>
    Records the usage of the base::JSONParser's non-RFC-8259-conforming
    extensions when parsing JSON documents. This histogram is emitted each time
    an instance of non-conforming syntax is detected in a document.
  </summary>
</histogram>

<histogram name="Security.NavigationRequestSecurityLevel"
    enum="NavigationRequestSecurityLevel" expires_after="2024-03-01">
  <owner>jdeblasio@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records the security level (e.g. secure, not secure, etc.) of each HTTP
    request, recording one histogram per fetch (i.e. including redirects).
  </summary>
</histogram>

<histogram base="true" name="Security.PageEndReason" enum="PageEndReason"
    expires_after="2023-09-10">
  <owner>cthomp@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records the reason the page visit ended (e.g., reload, tab closed, new
    navigation, etc.) for page loads that committed.
  </summary>
</histogram>

<histogram name="Security.PageInfo.AboutThisSiteInteraction"
    enum="AboutThisSiteInteraction" expires_after="2023-09-17">
  <owner>dullweber@chromium.org</owner>
  <owner>olesiamarukhno@chromium.org</owner>
  <summary>
    Tracks interactions with the AboutThisSite feature. Recorded when PageInfo
    is opened and when the user interacts with the AboutThisSite row.
  </summary>
</histogram>

<histogram name="Security.PageInfo.AboutThisSiteLanguageSupported"
    enum="Boolean" expires_after="2023-10-22">
  <owner>dullweber@chromium.org</owner>
  <owner>olesiamarukhno@chromium.org</owner>
  <summary>
    Tracks whether AboutThisSite is available for the user's application locale.
    Recorded every time PageInfo is opened.
  </summary>
</histogram>

<histogram name="Security.PageInfo.AboutThisSiteStatus"
    enum="AboutThisSiteStatus" expires_after="2023-08-27">
  <owner>dullweber@chromium.org</owner>
  <owner>olesiamarukhno@chromium.org</owner>
  <summary>
    Tracks status of AboutThisSite queries. Recorded every time PageInfo is
    opened and information about a site is requested.
  </summary>
</histogram>

<histogram name="Security.PageInfo.AdPersonalizationRowShown" enum="Boolean"
    expires_after="2023-09-10">
  <owner>dullweber@chromium.org</owner>
  <owner>sauski@google.com</owner>
  <summary>
    Tracks whether the Ads Personalization section was shown. Recorded every
    time PageInfo is opened.
  </summary>
</histogram>

<histogram name="Security.PageInfo.Cookies.HasFPSInfo" enum="Boolean"
    expires_after="M119">
  <owner>tommasin@chromium.org</owner>
  <owner>sauski@google.com</owner>
  <owner>olesiamarukhno@google.com</owner>
  <summary>
    Tracks whether the FPS section was shown in the Cookies subpage. Recorded
    every time Cookie subpage from PageInfo is opened.
  </summary>
</histogram>

<histogram name="Security.PageInfo.TimeOpen" units="ms"
    expires_after="2023-07-09">
  <owner>cthomp@chromium.org</owner>
  <owner>security-enamel@chromium.org</owner>
  <summary>
    Records the amount of time the Page Info bubble is open before the user
    closes it or takes an action which closes it.
  </summary>
</histogram>

<histogram name="Security.PageInfo.TimeOpen.Action" units="ms"
    expires_after="2023-09-10">
  <owner>cthomp@chromium.org</owner>
  <owner>security-enamel@chromium.org</owner>
  <summary>
    Records the amount of time the Page Info bubble is open before the user
    closes it, for cases where the user has performed an action inside it.
  </summary>
</histogram>

<histogram name="Security.PageInfo.TimeOpen.NoAction" units="ms"
    expires_after="2023-09-10">
  <owner>cthomp@chromium.org</owner>
  <owner>security-enamel@chromium.org</owner>
  <summary>
    Records the amount of time the Page Info bubble is open before the user
    closes it, for cases where the user performed no action inside it.
  </summary>
</histogram>

<histogram name="Security.PrivateNetworkAccess.CachedResourceCheckResult"
    enum="PrivateNetworkAccessCheckResult" expires_after="2023-07-09">
  <owner>titouan@chromium.org</owner>
  <owner>clamy@chromium.org</owner>
  <owner>mkwst@chromium.org</owner>
  <summary>
    Same as `Security.PrivateNetworkAccess.CheckResult`, but only recorded when
    the resource is loaded from the HTTP cache.
  </summary>
</histogram>

<histogram name="Security.PrivateNetworkAccess.CheckResult"
    enum="PrivateNetworkAccessCheckResult" expires_after="2023-10-22">
  <owner>titouan@chromium.org</owner>
  <owner>clamy@chromium.org</owner>
  <owner>mkwst@chromium.org</owner>
  <summary>
    Result of the Private Network Access Check on a new connection. Recorded
    once per call to network::URLLoader::OnConnected(), which may be more than
    once per URL request.
  </summary>
</histogram>

<histogram
    name="Security.PrivateNetworkAccess.MismatchedAddressSpacesDuringRequest"
    enum="Boolean" expires_after="2023-07-09">
  <owner>titouan@chromium.org</owner>
  <owner>clamy@chromium.org</owner>
  <owner>mkwst@chromium.org</owner>
  <summary>
    Recorded once per network::URLLoader instantiation. True if the request
    connected multiple times to different transports (e.g. for a
    partially-cached range request) and not all the computed IP address spaces
    were the same.
  </summary>
</histogram>

<histogram name="Security.PrivateNetworkAccess.PrivateIpInferrable"
    enum="Boolean" expires_after="2023-12-31">
  <owner>titouan@chromium.org</owner>
  <owner>lyf@chromium.org</owner>
  <owner>clamy@chromium.org</owner>
  <summary>
    Records whether a failed PNA check could have been avoided by inferring the
    request's target IP address space by recognizing that the request URL's host
    is a literal private IP address. Recorded at most once per URL request.
  </summary>
</histogram>

<histogram name="Security.PrivateNetworkAccess.PrivateIpResolveMatch"
    enum="Boolean" expires_after="2023-12-31">
  <owner>titouan@chromium.org</owner>
  <owner>lyf@chromium.org</owner>
  <owner>clamy@chromium.org</owner>
  <summary>
    Records whether a request to a literal private IP address resolved to that
    private IP address. Recorded at most once per call to
    `network::URLLoader::OnConnected()`, which may be more than once per URL
    request.
  </summary>
</histogram>

<histogram name="Security.SafetyTips.GetDomainInfoTime" units="ms"
    expires_after="2023-06-04">
  <owner>jdeblasio@chromium.org</owner>
  <owner>estark@chromium.org</owner>
  <owner>blundell@chromium.org</owner>
  <summary>
    Records the time duration that a check for the reputation status of a site
    spent in getting the domain info of the site on the main thread, or 0 if the
    domain info was obtained off of the main thread. Recorded on every check.
  </summary>
</histogram>

<histogram name="Security.SafetyTips.GetReputationStatusWithEngagedSitesTime"
    units="ms" expires_after="2023-10-08">
  <owner>jdeblasio@chromium.org</owner>
  <owner>estark@chromium.org</owner>
  <owner>blundell@chromium.org</owner>
  <summary>
    Records the time duration of a check for the reputation status of a site on
    the main thread. Recorded on every check.
  </summary>
</histogram>

<histogram name="Security.SafetyTips.Interaction" enum="SafetyTipInteraction"
    expires_after="2023-06-18">
  <owner>jdeblasio@chromium.org</owner>
  <owner>estark@chromium.org</owner>
  <summary>
    Records a user's interaction with a Safety Tip. Recorded every time a user
    uses one of the Safety Tip's buttons or dismisses it explicitly. Can be
    normalized against Security.SafetyTips.SafetyTipShown, filtered to users
    with the feature enabled to show the UI.
  </summary>
</histogram>

<histogram name="Security.SafetyTips.SafetyTipIgnoredPageLoad"
    enum="SafetyTipStatus" expires_after="2023-08-27">
  <owner>jdeblasio@chromium.org</owner>
  <owner>src/chrome/browser/lookalikes/OWNERS</owner>
  <summary>
    Records the Safety Tip status of a page after navigation commit for a page
    where the Safety Tip has previously been ignored.

    Note: This histogram was expired from 2021-12-26 until 2023-01-19.
  </summary>
</histogram>

<histogram name="Security.SafetyTips.SafetyTipShown" enum="SafetyTipStatus"
    expires_after="2023-09-17">
  <owner>jdeblasio@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records the Safety Tip status of a page after navigation commit or page
    visibility change.
  </summary>
</histogram>

<histogram name="Security.SCTAuditing.NumPersistedReportsLoaded"
    units="reports" expires_after="2023-09-10">
  <owner>cthomp@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records the number of persisted SCT auditing reports that were loaded and
    deserialized from disk, if SCT auditing is enabled. Invalid persisted
    reports are not counted. Recorded once shortly after browser startup (or
    when the network service restarts).
  </summary>
</histogram>

<histogram name="Security.SCTAuditing.OptIn.DedupeCacheHWM" units="reports"
    expires_after="2023-01-15">
  <owner>cthomp@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records the high-water-mark of the number of entries in the SCT auditing
    dedupe cache. Recorded on a timer hourly, if SCT auditing is enabled.
  </summary>
</histogram>

<histogram name="Security.SCTAuditing.OptIn.ReportCompletionStatus"
    enum="SCTAuditingReportCompletionStatus" expires_after="2023-10-08">
  <owner>cthomp@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records the final status of an SCT auditing report, when it has been
    successfully received or it has run out of retries.
  </summary>
</histogram>

<histogram name="Security.SCTAuditing.OptIn.ReportDeduplicated" enum="Boolean"
    expires_after="2023-09-17">
  <owner>cthomp@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records whether a report was deduplicated (i.e., the SCTs were already in
    the cache) or not. Recorded on each new report seen by the SCT auditing
    cache (i.e., on each connection using certificate transparency).
  </summary>
</histogram>

<histogram name="Security.SCTAuditing.OptIn.ReportersHWM" units="reporters"
    expires_after="2023-09-17">
  <owner>cthomp@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records the high-water-mark of the number of pending reporters in the SCT
    auditing cache. Recorded on a timer hourly, if SCT auditing is enabled.
  </summary>
</histogram>

<histogram name="Security.SCTAuditing.OptIn.ReportSampled" enum="Boolean"
    expires_after="2023-09-17">
  <owner>cthomp@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records whether a report was sampled to be sent to Safe Browsing. Recorded
    for each new report seen by the SCT auditing cache that was not
    deduplicated.
  </summary>
</histogram>

<histogram name="Security.SCTAuditing.OptIn.ReportSize" units="bytes"
    expires_after="2023-09-17">
  <owner>cthomp@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records the size of an SCT auditing report that will be sent to Safe
    Browsing (i.e., was not deduplicated and was sampled).
  </summary>
</histogram>

<histogram name="Security.SCTAuditing.OptIn.ReportSucceeded" enum="Boolean"
    expires_after="2023-09-17">
  <owner>cthomp@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records whether sending an SCT auditing report succeeded or not. This is
    recorded after we receive the headers from the server (or we stop due to a
    connection error).
  </summary>
</histogram>

<histogram name="Security.SCTAuditing.OptOut.DroppedDueToLogNotFound"
    enum="Boolean" expires_after="2023-09-17">
  <owner>cthomp@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records whether a hashdance report was dropped due to not finding the log
    metadata for the selected SCT. Recorded once when creating a new auditing
    report, but before the report is sampled or deduplicated.
  </summary>
</histogram>

<histogram name="Security.SCTAuditing.OptOut.LookupQueryResult"
    enum="SCTLookupQueryResult" expires_after="2023-09-17">
  <owner>cthomp@chromium.org</owner>
  <owner>nsatragno@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records the result of a hashdance lookup query. Recorded once per query
    regardless of whether the query succeeded, failed, or is a retry.
  </summary>
</histogram>

<histogram name="Security.SCTAuditing.OptOut.PopularSCTSkipped" enum="Boolean"
    expires_after="2023-09-17">
  <owner>cthomp@chromium.org</owner>
  <owner>nsatragno@chromium.org</owner>
  <owner>trusty-transport@chromium.org</owner>
  <summary>
    Records whether an SCT selected for a hashdance lookup query was skipped
    because it was found on the Popular SCTs list. Recorded once when creating a
    new auditing report, but before the report is sampled or deduplicated.
  </summary>
</histogram>

<histogram name="Security.SCTAuditing.OptOut.ReportCount" units="reports"
    expires_after="2023-09-17">
  <owner>cthomp@chromium.org</owner>
  <owner>jdeblasio@chromium.org</owner>
  <summary>
    Records how many full SCT auditing reports the client has sent (i.e., after
    a successful hashdance lookup query resulting in kSCTSuffixNotFound). This
    count is tracked per-client in a pref to limit how many full reports a
    client can send. This metric is emitted every time this count is checked by
    the SCT auditing code, after sampling is performed, and only once per report
    (including across browser restarts). This metric is only emitted for SCT
    auditing hashdance users.
  </summary>
</histogram>

<histogram name="Security.SecurityLevel.DownloadStarted" enum="SecurityLevel"
    expires_after="2023-06-30">
  <owner>cthomp@chromium.org</owner>
  <owner>security-enamel@chromium.org</owner>
  <summary>
    Records the security level of the page that initiated a download (rather
    than the security state of the connection to the download URL itself). The
    recorded security level is the level of the page the download was initiated
    from, not that of the download URL. This histogram is not recorded for
    downloads that are initiated in a new tab or window, as the security level
    of the initiating page cannot be tracked.
  </summary>
</histogram>

<histogram name="Security.SecurityLevel.FormSubmission" enum="SecurityLevel"
    expires_after="2023-06-30">
  <owner>carlosil@chromium.org</owner>
  <owner>cthomp@chromium.org</owner>
  <summary>
    Records the security level of a page when submitting a form. This histogram
    is recorded whenever a form submission navigation begins. The recorded
    security level is the level of the page the form was submitted from, not the
    one that the form targets.
  </summary>
</histogram>

<histogram name="Security.SecurityLevel.InsecureMainFrameFormSubmission"
    enum="SecurityLevel" expires_after="2023-08-14">
  <owner>estark@chromium.org</owner>
  <owner>carlosil@chromium.org</owner>
  <summary>
    Records the security level of a page when submitting a form on a top-frame
    navigation with a non-cryptographic scheme. This histogram is recorded
    whenever a form submission navigation begins. The recorded security level is
    the level of the page the form was submitted from, not the one that the form
    targets.
  </summary>
</histogram>

<histogram name="Security.SecurityLevel.OnCommit" enum="SecurityLevel"
    expires_after="2023-09-03">
  <owner>cthomp@chromium.org</owner>
  <owner>security-enamel@chromium.org</owner>
  <summary>
    Records the security level of a page at the time the navigation commits.
    Note that the security level of a page can change after commit time, so this
    histogram should often be compared against
    Security.SecurityLevel.OnComplete.
  </summary>
</histogram>

<histogram name="Security.SecurityLevel.OnComplete" enum="SecurityLevel"
    expires_after="2023-09-03">
  <owner>cthomp@chromium.org</owner>
  <owner>security-enamel@chromium.org</owner>
  <summary>
    Records the security level of a page at the end of the page visit (i.e.,
    navigating away from the page, reloading the page, clicking a link, closing
    the tab, etc.). Note that this security level can be different than the
    initial security level of the page, so this histogram should often be
    compared against Security.SecuritLevel.OnCommit.
  </summary>
</histogram>

<histogram base="true" name="Security.SiteEngagement" units="units"
    expires_after="2023-09-03">
  <owner>cthomp@chromium.org</owner>
  <owner>security-enamel@chromium.org</owner>
  <summary>
    The final Site Engagement score (0 to 100) of a URL during a visit to a
    page. Recorded when the user closes the page or initiates a new navigation.
  </summary>
</histogram>

<histogram base="true" name="Security.TimeOnPage2" units="ms"
    expires_after="2023-09-03">
  <owner>cthomp@chromium.org</owner>
  <owner>security-enamel@chromium.org</owner>
  <summary>
    Records the time spent on the page (the time that the page was in the
    foreground from the start of the navigation to the page visit completing due
    to a new navigation or the tab being closed). This aggregates all foreground
    time over the entire visit (multiple times in the foreground are added
    together).
  </summary>
</histogram>

<histogram name="SiteIsolation.BrowsingInstance.MaxCountPerProcess"
    units="units" expires_after="2023-06-18">
  <owner>wjmaclean@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <summary>
    The maximum number of BrowsingInstances seen in a RenderProcessHost over its
    lifetime. Recorded once when
    ChildProcessImpl::SecurityState::~SecurityState() is invoked.
  </summary>
</histogram>

<histogram name="SiteIsolation.BrowsingInstanceCount" units="units"
    expires_after="2023-08-27">
  <owner>alexmos@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <summary>
    The count of all current BrowsingInstances. Recorded once per UMA ping.
  </summary>
</histogram>

<histogram base="true" name="SiteIsolation.CORBProtection.CacheHeuristic"
    enum="CrossOriginProtectionDecision" expires_after="M83">
  <owner>krstnmnlsn@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <summary>
    The blocking decision CORB would have made on the response, if the request
    was cross-origin. Reported if the response looked sensitive under the cache
    heuristic (i.e. had Cache-Control: Private and Vary: Origin response
    headers).
  </summary>
</histogram>

<histogram base="true"
    name="SiteIsolation.CORBProtection.CacheHeuristic.ProtectedMimeType"
    enum="BooleanSupported" expires_after="M83">
<!-- suffixed with Block*WithRangeSupport -->

  <owner>krstnmnlsn@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <summary>
    True if the response has an Accept-Ranges header, which indicates the server
    supports range requests on the resource and could be used to bypass CORB.
    Only reported if the resource looked sensitive under the Cache heuristic and
    was a protected MIME type.
  </summary>
</histogram>

<histogram base="true" name="SiteIsolation.CORBProtection.CORSHeuristic"
    enum="CrossOriginProtectionDecision" expires_after="M83">
  <owner>krstnmnlsn@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <summary>
    The blocking decision CORB would have made on the response, if the request
    was cross-origin. Reported if the response looked sensitive under the CORS
    heuristic (i.e. had the Access-Control-Allow-Origin header with a value
    other than * or null).
  </summary>
</histogram>

<histogram base="true"
    name="SiteIsolation.CORBProtection.CORSHeuristic.ProtectedMimeType"
    enum="BooleanSupported" expires_after="M83">
<!-- suffixed with Block*WithRangeSupport -->

  <owner>krstnmnlsn@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <summary>
    True if the response has an Accept-Ranges header, which indicates the server
    supports range requests on the resource and could be used to bypass CORB.
    Only reported if the resource looked sensitive under the CORS heuristic and
    was a protected MIME type.
  </summary>
</histogram>

<histogram base="true"
    name="SiteIsolation.CORBProtection.ProtectedMimeType.BlockedWithoutSniffing.HasNoSniff"
    enum="BooleanHasNoSniff" expires_after="M83">
  <owner>krstnmnlsn@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <summary>
    True if the response has a nosniff header. If the nosniff header is not
    present, then CORB must have decided to block without sniffing due to a
    partial response, or because the MIME type was a never sniff type. Only
    reported on resources CORB would have blocked/protected without sniffing
    that have a protected MIME type.
  </summary>
</histogram>

<histogram name="SiteIsolation.CORBProtection.SensitiveResource"
    enum="BooleanSensitive" expires_after="M83">
  <owner>krstnmnlsn@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <summary>
    True if the resource was found to be sensitive by either the CORS or Cache
    heuristics. Recorded for every resource CORB sees.
  </summary>
</histogram>

<histogram name="SiteIsolation.CORBProtection.SensitiveWithRangeSupport"
    enum="BooleanSupported" expires_after="M83">
  <owner>krstnmnlsn@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <summary>
    True if the response has an Accept-Ranges header, which indicates the server
    supports range requests on the resource. Only reported if the response
    looked sensitive under the cache or CORS heuristics.
  </summary>
</histogram>

<histogram name="SiteIsolation.IsolatableSandboxedIframes" units="processes"
    expires_after="2023-05-09">
  <owner>wjmaclean@chromium.org</owner>
  <owner>alexmos@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <summary>
    The number of sandboxed iframes that (i) are same-site (and therefore not
    already process-isolated) and (ii) eligible to be process isolated if
    SiteIsolationPolicy::AreIsolatedSandboxedIframesEnabled() is true. A
    sandboxed iframe is eligible for process-isolation so long as it doesn't
    have `allow-same-origin` among its sandbox permissions, and it isn't an
    about:blank url. This metric measures the upper bound on the process
    overhead of isolating sandboxed iframes, namely the case where every
    sandboxed iframe is placed in its own process. Note that the computation of
    this metric is independent of the current process model. Recorded once per
    UMA ping.
  </summary>
</histogram>

<histogram name="SiteIsolation.IsolatableSandboxedIframes.UniqueOrigins"
    units="processes" expires_after="2023-05-09">
  <owner>wjmaclean@chromium.org</owner>
  <owner>alexmos@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <summary>
    The number of unique origins among the sandboxed iframes reported in
    SiteIsolation.IsolatableSandboxedIframes. Used to estimate the potential
    process overhead if a per-origin process model is used for isolating the
    sandboxed iframes instead of the (current) per-site process model. Note that
    the computation of this metric is independent of the current process model.
    Recorded once per UMA ping.
  </summary>
</histogram>

<histogram name="SiteIsolation.IsolatableSandboxedIframes.UniqueSites"
    units="processes" expires_after="2023-05-09">
  <owner>wjmaclean@chromium.org</owner>
  <owner>alexmos@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <summary>
    The number of unique sites among the sandboxed iframes reported in
    SiteIsolation.IsolatableSandboxedIframes. Note that the computation of this
    metric is independent of the current process model. Recorded once per UMA
    ping.
  </summary>
</histogram>

<histogram name="SiteIsolation.IsPasswordFormSubmittedInDedicatedProcess"
    enum="SiteIsolationIsDedicatedProcess" expires_after="2023-08-07">
  <owner>alexmos@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <summary>
    Logs whether or not a password form was submitted from a site-isolated
    process that's dedicated to a single site. Recorded when a password form is
    submitted.
  </summary>
</histogram>

<histogram name="SiteIsolation.ORB.BlockingReason"
    enum="OrbBlockingDecisionReason" expires_after="2023-08-08">
  <owner>creis@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <owner>vogelheim@chromium.org</owner>
  <summary>
    Logs why ORB has reached a blocking decision.

    Logged for each response processed by OpaqueResponseBlockingAnalyzer.
  </summary>
</histogram>

<histogram name="SiteIsolation.ORB.CorbVsOrb" enum="CorbVsOrb"
    expires_after="2023-10-08">
  <owner>creis@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <owner>vogelheim@chromium.org</owner>
  <summary>
    Logs whether ORB and CORB would take the same allow-vs-block decision. This
    should help assess the backcompatibility risk of shipping ORB.

    Logged at the end of lifetime of the ResponseAnalyzer (i.e. after processing
    each response that is subject to CORB - most NetworkService responses, but
    also CORB-covered web bundles).
  </summary>
</histogram>

<histogram name="SiteIsolation.ORB.CorbVsOrb.OrbBlockedAndCorbDidnt.Reason"
    enum="OrbBlockingDecisionReason" expires_after="2023-10-08">
  <owner>creis@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <owner>vogelheim@chromium.org</owner>
  <summary>
    Logs why ORB has reached a blocking decision.

    Logged when it turned out that CORB wouldn't have blocked the response, but
    ORB blocked the response.
  </summary>
</histogram>

<histogram name="SiteIsolation.ORB.ResponseHeadersHeuristic.Decision"
    enum="OpaqueResponseBlocking_ResponseHeadersHeuristic" expires_after="M92">
  <obsolete>
    Removed in Feb 2022 / M100.

    Old results are preserved in
    https://docs.google.com/document/d/1LkF7a-_RXg0uQQdk86FQHq7CMW5pKozPDmmbnJJRhY8/edit#heading=h.6labqs212jfn
  </obsolete>
  <owner>creis@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <summary>
    The approximation of a route that Opaque Response Blocking (ORB) algorithm
    would have taken to decide whether to block the response or not. The logged
    value is based on heuristics that only look at the HTTP response headers,
    and attempt to approximate if the full ORB algorithm would need to parse the
    response body as Javascript (vs also reaching a decision purely based on the
    HTTP response headers).

    Note that only partial ORB algorithm is used for logging the UMA (e.g. no
    multimedia sniffing and/or 206-response processing is done). This means that
    the results overestimate how many responses need Javascript parsing.

    Logged for each final HTTP/HTTPS response processed by the NetworkService.
  </summary>
</histogram>

<histogram name="SiteIsolation.ORB.ResponseHeadersHeuristic.{OrbDecision}"
    enum="RequestDestination" expires_after="M92">
  <obsolete>
    Removed in Feb 2022 / M100.

    Old results are preserved in
    https://docs.google.com/document/d/1LkF7a-_RXg0uQQdk86FQHq7CMW5pKozPDmmbnJJRhY8/edit#heading=h.6labqs212jfn
  </obsolete>
  <owner>creis@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <summary>
    The request destination (e.g. script vs image) of a response that Opaque
    Response Blocking (ORB) algorithm processed {OrbDecision}.

    Note that only partial ORB algorithm is used for logging the UMA (e.g. no
    multimedia sniffing and/or 206-response processing is done). This means that
    the results overestimate how many responses need Javascript parsing.

    Logged for each final HTTP/HTTPS response processed by the NetworkService.
  </summary>
  <token key="OrbDecision">
    <variant name="ProcessedBasedOnHeaders"
        summary="based on HTTP response headers"/>
    <variant name="RequiresJavascriptParsing"
        summary="with required Javascript parsing"/>
  </token>
</histogram>

<histogram name="SiteIsolation.OutOfProcessIframes" units="oopifs"
    expires_after="2023-09-17">
  <owner>alexmos@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <owner>nasko@chromium.org</owner>
  <summary>
    The count of all out-of-process iframes. Recorded once per UMA ping.
  </summary>
</histogram>

<histogram name="SiteIsolation.OutOfProcessInnerFrameTrees" units="frame trees"
    expires_after="2024-03-14">
  <owner>alexmos@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <owner>nasko@chromium.org</owner>
  <summary>
    The count of all out-of-process inner frame trees. Recorded once per UMA
    ping.
  </summary>
</histogram>

<histogram name="SiteIsolation.ProxyCount" units="proxies"
    expires_after="2023-09-10">
  <owner>alexmos@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <summary>
    The count of all RenderFrameProxyHosts. Recorded once per UMA ping.
  </summary>
</histogram>

<histogram name="SiteIsolation.ProxyCountPerBrowsingInstance" units="units"
    expires_after="2023-07-09">
  <owner>alexmos@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <summary>
    The count of RenderFrameProxyHosts in each BrowsingInstance. Recorded each
    UMA ping, once per BrowsingInstance.
  </summary>
</histogram>

<histogram name="SiteIsolation.ReusePendingOrCommittedSite.CouldReuse2"
    enum="ReusePendingOrCommittedSiteEnum" expires_after="2023-06-04">
  <owner>clamy@chromium.org</owner>
  <summary>
    Whether SiteInstances with a ProcessReusePolicy of
    REUSE_PENDING_OR_COMMITTED_SITE could reuse an existing RenderProcessHost or
    they had to create a new one. True when they reused an existing process,
    false when they created a new one.

    (Was expired between M77 and M105 before moving on to V2.)
  </summary>
</histogram>

<histogram
    name="SiteIsolation.ReusePendingOrCommittedSite.TimeSinceReusableProcessDestroyed"
    units="ms" expires_after="2023-06-25">
  <owner>jessemckenna@google.com</owner>
  <owner>olivierli@chromium.org</owner>
  <summary>
    Recorded on navigations with a ProcessReusePolicy of
    REUSE_PENDING_OR_COMMITTED_SITE (mostly subframe navigations). Measures the
    time since a RenderProcessHost hosting the destination URL was last
    destroyed, up to 10 seconds. If no host matching the destination was
    recently destroyed, a sentinel value of 20 seconds is used.
  </summary>
</histogram>

<histogram name="SiteIsolation.SavedOAuthSites.Size" units="origins"
    expires_after="2023-08-20">
  <owner>alexmos@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <summary>
    The number of currently saved sites that had been isolated due to OAuth.
    This is only used by Site Isolation on Android. Recorded once on browser
    startup.
  </summary>
</histogram>

<histogram name="SiteIsolation.SavedUserTriggeredIsolatedOrigins.Size"
    units="origins" expires_after="2023-08-20">
  <owner>alexmos@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <summary>
    The number of currently saved user-triggered isolated sites. This includes
    sites where the user has entered a password while using Site Isolation for
    password sites (which is a currently active site isolation mode on Android).
    Recorded once on browser startup.
  </summary>
</histogram>

<histogram name="SiteIsolation.SavedWebTriggeredIsolatedOrigins.Size"
    units="origins" expires_after="2023-08-20">
  <owner>alexmos@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <summary>
    The number of currently saved web-triggered isolated sites. This includes
    sites that were isolated due to Cross-Origin-Opener-Policy headers, which is
    a heuristic used for site isolation on Android. Recorded once on browser
    startup.
  </summary>
</histogram>

<histogram name="SiteIsolation.SiteInstancesPerBrowsingInstance" units="units"
    expires_after="2023-09-03">
  <owner>alexmos@chromium.org</owner>
  <owner>creis@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <owner>nasko@chromium.org</owner>
  <summary>
    The count of SiteInstances in a single BrowsingInstance. Recorded each UMA
    ping, once per BrowsingInstance.
  </summary>
</histogram>

<histogram name="SiteIsolation.XSD.Browser.Action"
    enum="SiteIsolationResponseAction" expires_after="2020-06-01">
  <owner>creis@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <summary>
    Various actions related to cross-site document blocking in the browser
    process, indicating whether the response was blocked from the renderer.
    Recorded as the response is processed in the network stack.
  </summary>
</histogram>

<histogram name="SiteIsolation.XSD.Browser.Blocked.CanonicalMimeType"
    enum="CorbCanonicalMimeType" expires_after="M81">
  <owner>creis@chromium.org</owner>
  <owner>lukasza@chromium.org</owner>
  <summary>
    The total count of responses that were blocked by the cross-site document
    blocking logic in the browser process. Recorded with a canonical MIME type
    when the response is blocked.
  </summary>
</histogram>

</histograms>

</histogram-configuration>