wireshark/ui/qt/widgets/capture_filter_edit.cpp

/* capture_filter_edit.cpp
 *
 * Wireshark - Network traffic analyzer
 * By Gerald Combs <gerald@wireshark.org>
 * Copyright 1998 Gerald Combs
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 */

#include "config.h"

#include <glib.h>

#include <epan/proto.h>

#include "capture_opts.h"

#include <ui/capture_globals.h>
#include <wsutil/filter_files.h>
#include <wsutil/utf8_entities.h>

#include <ui/qt/widgets/capture_filter_edit.h>
#include "capture_filter_syntax_worker.h"
#include "filter_dialog.h"
#include <ui/qt/widgets/stock_icon_tool_button.h>
#include "main_application.h"

#include <QComboBox>
#include <QCompleter>
#include <QMenu>
#include <QMessageBox>
#include <QPainter>
#include <QStringListModel>
#include <QStyleOptionFrame>

#include <ui/qt/utils/qt_ui_utils.h>

// To do:
// - This duplicates some DisplayFilterEdit code.
// - We need simplified (button- and dropdown-free) versions for use in dialogs and field-only checking.

static const QString libpcap_primitive_chars_ = "-0123456789abcdefghijklmnopqrstuvwxyz";

// Primitives are from pcap-filter.manmisc
static const QStringList libpcap_primitives_ = QStringList()
        // "Abbreviations for..."
        << "ether proto"
        << "ip" << "ip6" << "arp" << "rarp" << "atalk" << "aarp" << "decnet" << "iso" << "stp" << "ipx" << "netbeui"
        << "moprc" << "mopdl"
        // ip proto
        << "tcp" << "udp" << "icmp"
        // iso proto
        << "clnp" << "esis" << "isis"
        // IS‐IS PDU types
        << "l1" << "l2" << "iih" << "lsp" << "snp" << "csnp" << "psnp"

        // grep -E '^\.IP "\\fB.*\\f(R"|P)$' pcap-filter.manmisc | sed -e 's/^\.IP "\\fB/<< "/' -e 's/ *\\f.*/"/' | sort -u
        << "action"
        << "clnp"
        << "decnet dst"
        << "decnet host"
        << "decnet src"
        << "dir"
        << "dst host"
        << "dst net"
        << "dst port"
        << "dst portrange"
        << "ether broadcast"
        << "ether dst"
        << "ether host"
        << "ether multicast"
        << "ether src"
        << "gateway"
        << "greater"
        << "host"
        << "ifname"
        << "ip broadcast"
        << "ip multicast"
        << "ip proto"
        << "ip protochain"
        << "ip6 multicast"
        << "ip6 proto"
        << "ip6 protochain"
        << "iso proto"
        << "l1"
        << "lat"
        << "less"
        << "mpls"
        << "net"
        << "on"
        << "port"
        << "portrange"
        << "reason"
        << "rnr"
        << "rset"
        << "rulenum"
        << "ruleset"
        << "src host"
        << "src net"
        << "src port"
        << "src portrange"
        << "srnr"
        << "subrulenum"
        << "subtype"
        << "type"
        << "vlan"
        << "wlan addr1"
        << "wlan addr2"
        << "wlan addr3"
        << "wlan addr4"
        << "wlan ra"
        << "wlan ta"
           ;

CaptureFilterEdit::CaptureFilterEdit(QWidget *parent, bool plain) :
    SyntaxLineEdit(parent),
    plain_(plain),
    field_name_only_(false),
    enable_save_action_(false),
    save_action_(NULL),
    remove_action_(NULL),
    actions_(Q_NULLPTR),
    bookmark_button_(NULL),
    clear_button_(NULL),
    apply_button_(NULL)
{
    setAccessibleName(tr("Capture filter entry"));

    completion_model_ = new QStringListModel(this);
    setCompleter(new QCompleter(completion_model_, this));
    setCompletionTokenChars(libpcap_primitive_chars_);

    setConflict(false);

    if (!plain_) {
        bookmark_button_ = new StockIconToolButton(this, "x-capture-filter-bookmark");
        bookmark_button_->setCursor(Qt::ArrowCursor);
        bookmark_button_->setMenu(new QMenu(bookmark_button_));
        bookmark_button_->setPopupMode(QToolButton::InstantPopup);
        bookmark_button_->setToolTip(tr("Manage saved bookmarks."));
        bookmark_button_->setIconSize(QSize(14, 14));
        bookmark_button_->setStyleSheet(
                    "QToolButton {"
                    "  border: none;"
                    "  background: transparent;" // Disables platform style on Windows.
                    "  padding: 0 0 0 0;"
                    "}"
                    "QToolButton::menu-indicator { image: none; }"
            );
        connect(bookmark_button_, &StockIconToolButton::clicked, this, &CaptureFilterEdit::bookmarkClicked);

        clear_button_ = new StockIconToolButton(this, "x-filter-clear");
        clear_button_->setCursor(Qt::ArrowCursor);
        clear_button_->setToolTip(QString());
        clear_button_->setIconSize(QSize(14, 14));
        clear_button_->setStyleSheet(
                "QToolButton {"
                "  border: none;"
                "  background: transparent;" // Disables platform style on Windows.
                "  padding: 0 0 0 0;"
                "  margin-left: 1px;"
                "}"
                );
        connect(clear_button_, &StockIconToolButton::clicked, this, &CaptureFilterEdit::clearFilter);
    }

    connect(this, &CaptureFilterEdit::textChanged, this,
            static_cast<void (CaptureFilterEdit::*)(const QString &)>(&CaptureFilterEdit::checkFilter));

#if 0
    // Disable the apply button for now
    if (!plain_) {
        apply_button_ = new StockIconToolButton(this, "x-filter-apply");
        apply_button_->setCursor(Qt::ArrowCursor);
        apply_button_->setEnabled(false);
        apply_button_->setToolTip(tr("Apply this filter string to the display."));
        apply_button_->setIconSize(QSize(24, 14));
        apply_button_->setStyleSheet(
                "QToolButton {"
                "  border: none;"
                "  background: transparent;" // Disables platform style on Windows.
                "  padding: 0 0 0 0;"
                "}"
                );
        connect(apply_button_, &StockIconToolButton::clicked, this, &CaptureFilterEdit::applyCaptureFilter);
    }
#endif
    connect(this, &CaptureFilterEdit::returnPressed, this, &CaptureFilterEdit::applyCaptureFilter);

    int frameWidth = style()->pixelMetric(QStyle::PM_DefaultFrameWidth);
    QSize bksz;
    if (bookmark_button_) bksz = bookmark_button_->sizeHint();
    QSize cbsz;
    if (clear_button_) cbsz = clear_button_->sizeHint();
    QSize apsz;
    if (apply_button_) apsz = apply_button_->sizeHint();

    setStyleSheet(QString(
            "CaptureFilterEdit {"
            "  padding-left: %1px;"
            "  margin-left: %2px;"
            "  margin-right: %3px;"
            "}"
            )
            .arg(frameWidth + 1)
            .arg(bksz.width())
            .arg(cbsz.width() + apsz.width() + frameWidth + 1)
            );

    QComboBox *cf_combo = qobject_cast<QComboBox *>(parent);
    if (cf_combo) {
#if QT_VERSION >= QT_VERSION_CHECK(5, 15, 0)
        connect(cf_combo, static_cast<void (QComboBox::*)(const QString &)>(&QComboBox::textActivated),
                this, &CaptureFilterEdit::textEdited);
#else
        connect(cf_combo, static_cast<void (QComboBox::*)(const QString &)>(&QComboBox::activated),
                this, &CaptureFilterEdit::textEdited);
#endif
    }

    syntax_thread_ = new QThread;
    syntax_worker_ = new CaptureFilterSyntaxWorker;
    syntax_worker_->moveToThread(syntax_thread_);
    connect(mainApp, &MainApplication::appInitialized, this, &CaptureFilterEdit::updateBookmarkMenu);
    connect(mainApp, &MainApplication::captureFilterListChanged, this, &CaptureFilterEdit::updateBookmarkMenu);
    connect(syntax_thread_, &QThread::started, this,
            static_cast<void (CaptureFilterEdit::*)()>(&CaptureFilterEdit::checkFilter));
    connect(syntax_worker_, &CaptureFilterSyntaxWorker::syntaxResult,
            this, &CaptureFilterEdit::setFilterSyntaxState);
    connect(this, &CaptureFilterEdit::captureFilterChanged, syntax_worker_, &CaptureFilterSyntaxWorker::checkFilter);
    syntax_thread_->start();
    updateBookmarkMenu();
}

CaptureFilterEdit::~CaptureFilterEdit()
{
    syntax_thread_->quit();
    syntax_thread_->wait();
    delete syntax_thread_;
    delete syntax_worker_;
}

void CaptureFilterEdit::paintEvent(QPaintEvent *evt) {
    SyntaxLineEdit::paintEvent(evt);

    if (bookmark_button_) {
        // Draw the right border by hand. We could try to do this in the
        // style sheet but it's a pain.
#ifdef Q_OS_MAC
        QColor divider_color = Qt::gray;
#else
        QColor divider_color = palette().shadow().color();
#endif
        QPainter painter(this);
        painter.setPen(divider_color);
        QRect cr = contentsRect();
        QSize bksz = bookmark_button_->size();
        painter.drawLine(bksz.width(), cr.top(), bksz.width(), cr.bottom() + 1);
    }
}

void CaptureFilterEdit::resizeEvent(QResizeEvent *)
{
    QSize cbsz;
    if (clear_button_) cbsz = clear_button_->sizeHint();
    QSize apsz;
    if (apply_button_) apsz = apply_button_->sizeHint();

    int frameWidth = style()->pixelMetric(QStyle::PM_DefaultFrameWidth);
    if (clear_button_) {
        clear_button_->move(contentsRect().right() - frameWidth - cbsz.width() - apsz.width(),
                            contentsRect().top());
        clear_button_->setMinimumHeight(contentsRect().height());
        clear_button_->setMaximumHeight(contentsRect().height());
    }
    if (apply_button_) {
        apply_button_->move(contentsRect().right() - frameWidth - apsz.width(),
                            contentsRect().top());
        apply_button_->setMinimumHeight(contentsRect().height());
        apply_button_->setMaximumHeight(contentsRect().height());
    }
    if (bookmark_button_) {
        bookmark_button_->setMinimumHeight(contentsRect().height());
        bookmark_button_->setMaximumHeight(contentsRect().height());
    }
}

void CaptureFilterEdit::setConflict(bool conflict)
{
    if (conflict) {
        //: This is a very long concept that needs to fit into a short space.
        placeholder_text_ = tr("Multiple filters selected. Override them here or leave this blank to preserve them.");
        setToolTip(tr("<p>The interfaces you have selected have different capture filters."
                      " Typing a filter here will override them. Doing nothing will"
                      " preserve them.</p>"));
    } else {
        placeholder_text_ = QString(tr("Enter a capture filter %1")).arg(UTF8_HORIZONTAL_ELLIPSIS);
        setToolTip(QString());
    }
    setPlaceholderText(placeholder_text_);
}

// XXX Make this private along with setConflict.
QPair<const QString, bool> CaptureFilterEdit::getSelectedFilter()
{
    QString user_filter;
    bool filter_conflict = false;
#ifdef HAVE_LIBPCAP
    int selected_devices = 0;

    for (guint i = 0; i < global_capture_opts.all_ifaces->len; i++) {
        interface_t *device = &g_array_index(global_capture_opts.all_ifaces, interface_t, i);
        if (device->selected) {
            selected_devices++;
            if (selected_devices == 1) {
                user_filter = device->cfilter;
            } else {
                if (user_filter.compare(device->cfilter)) {
                    filter_conflict = true;
                }
            }
        }
    }
#endif // HAVE_LIBPCAP
    return QPair<const QString, bool>(user_filter, filter_conflict);
}

void CaptureFilterEdit::checkFilter(const QString& filter)
{
    if (text().length() == 0 && actions_ && actions_->checkedAction())
        actions_->checkedAction()->setChecked(false);

    setSyntaxState(Busy);
    mainApp->popStatus(MainApplication::FilterSyntax);
    setToolTip(QString());
    bool empty = filter.isEmpty();

    setConflict(false);
    if (bookmark_button_) {
        bool match = false;

        FilterListModel model(FilterListModel::Capture);
        QModelIndex idx = model.findByExpression(text());
        if (idx.isValid()) {
            match = true;

            bookmark_button_->setStockIcon("x-filter-matching-bookmark");
            if (remove_action_) {
                remove_action_->setData(text());
                remove_action_->setEnabled(true);
            }
        } else {
            bookmark_button_->setStockIcon("x-capture-filter-bookmark");
            if (remove_action_) {
                remove_action_->setEnabled(false);
            }
        }

        enable_save_action_ = (!match && !filter.isEmpty());
        if (save_action_) {
            save_action_->setEnabled(false);
        }
    }

    if (apply_button_) {
        apply_button_->setEnabled(false);
    }

    if (clear_button_) {
        clear_button_->setVisible(!empty);
    }

    if (empty) {
        setFilterSyntaxState(filter, Empty, QString());
    } else {
        emit captureFilterChanged(filter);
    }
}

void CaptureFilterEdit::checkFilter()
{
    checkFilter(text());
}

void CaptureFilterEdit::updateBookmarkMenu()
{
    if (!bookmark_button_)
        return;

    QMenu *bb_menu = bookmark_button_->menu();
    bb_menu->clear();

    save_action_ = bb_menu->addAction(tr("Save this filter"));
    connect(save_action_, &QAction::triggered, this, &CaptureFilterEdit::saveFilter);
    remove_action_ = bb_menu->addAction(tr("Remove this filter"));
    connect(remove_action_, &QAction::triggered, this, &CaptureFilterEdit::removeFilter);
    QAction *manage_action = bb_menu->addAction(tr("Manage Capture Filters"));
    connect(manage_action, &QAction::triggered, this, &CaptureFilterEdit::showFilters);
    bb_menu->addSeparator();

    FilterListModel model(FilterListModel::Capture);
    QModelIndex idx = model.findByExpression(text());

    int one_em = bb_menu->fontMetrics().height();

    if (! actions_)
        actions_ = new QActionGroup(this);

    for (int row = 0; row < model.rowCount(); row++)
    {
        QModelIndex nameIdx = model.index(row, FilterListModel::ColumnName);
        QString name = nameIdx.data().toString();
        QString expr = model.index(row, FilterListModel::ColumnExpression).data().toString();
        QString prep_text = QString("%1: %2").arg(name).arg(expr);

        prep_text = bb_menu->fontMetrics().elidedText(prep_text, Qt::ElideRight, one_em * 40);
        QAction * prep_action = bb_menu->addAction(prep_text);
        prep_action->setCheckable(true);
        if (nameIdx == idx)
            prep_action->setChecked(true);

        actions_->addAction(prep_action);
        prep_action->setProperty("capture_filter", expr);
        connect(prep_action, &QAction::triggered, this, &CaptureFilterEdit::prepareFilter);
    }

    checkFilter();
}

void CaptureFilterEdit::setFilterSyntaxState(QString filter, int state, QString err_msg)
{
    if (filter.compare(text()) == 0) { // The user hasn't changed the filter
        setSyntaxState((SyntaxState)state);
        if (!err_msg.isEmpty()) {
            mainApp->pushStatus(MainApplication::FilterSyntax, err_msg);
            setToolTip(err_msg);
        }
    }

    bool valid = (state != Invalid);

    if (valid) {
        if (save_action_) {
            save_action_->setEnabled(enable_save_action_);
        }
        if (apply_button_) {
            apply_button_->setEnabled(true);
        }
    }

    emit captureFilterSyntaxChanged(valid);
}

void CaptureFilterEdit::bookmarkClicked()
{
    emit addBookmark(text());
}

void CaptureFilterEdit::clearFilter()
{
    clear();
    emit textEdited(text());
}

void CaptureFilterEdit::buildCompletionList(const QString &primitive_word, const QString &preamble _U_)
{
    if (primitive_word.length() < 1) {
        completion_model_->setStringList(QStringList());
        return;
    }

    // Grab matching capture filters from our parent combo and from the
    // saved capture filters file. Skip ones that look like single fields
    // and assume they will be added below.
    QStringList complex_list;
    QComboBox *cf_combo = qobject_cast<QComboBox *>(parent());
    if (cf_combo) {
        for (int i = 0; i < cf_combo->count() ; i++) {
            QString recent_filter = cf_combo->itemText(i);

            if (isComplexFilter(recent_filter)) {
                complex_list << recent_filter;
            }
        }
    }
    FilterListModel model(FilterListModel::Capture);
    for (int row = 0; row < model.rowCount(); row++)
    {
        QString saved_filter = model.index(row, FilterListModel::ColumnExpression).data().toString();

        if (isComplexFilter(saved_filter) && !complex_list.contains(saved_filter)) {
            complex_list << saved_filter;
        }
    }

    // libpcap has a small number of primitives so we just add the whole list
    // sans the current word.
    QStringList primitive_list = libpcap_primitives_;
    primitive_list.removeAll(primitive_word);

    completion_model_->setStringList(complex_list + primitive_list);
    completer()->setCompletionPrefix(primitive_word);
}

void CaptureFilterEdit::applyCaptureFilter()
{
    if (syntaxState() == Invalid) {
        return;
    }

    emit startCapture();
}

void CaptureFilterEdit::saveFilter()
{
    FilterDialog *capture_filter_dlg = new FilterDialog(window(), FilterDialog::CaptureFilter, text());
    capture_filter_dlg->setWindowModality(Qt::ApplicationModal);
    capture_filter_dlg->setAttribute(Qt::WA_DeleteOnClose);
    capture_filter_dlg->show();
}

void CaptureFilterEdit::removeFilter()
{
    if (! actions_ || ! actions_->checkedAction())
        return;

    QAction *ra = actions_->checkedAction();
    if (ra->property("capture_filter").toString().isEmpty())
        return;

    QString remove_filter = ra->property("capture_filter").toString();

    FilterListModel model(FilterListModel::Capture);
    QModelIndex idx = model.findByExpression(remove_filter);
    if (idx.isValid())
    {
        model.removeFilter(idx);
        model.saveList();
    }

    updateBookmarkMenu();
}

void CaptureFilterEdit::showFilters()
{
    FilterDialog *capture_filter_dlg = new FilterDialog(window(), FilterDialog::CaptureFilter);
    capture_filter_dlg->setWindowModality(Qt::ApplicationModal);
    capture_filter_dlg->setAttribute(Qt::WA_DeleteOnClose);
    capture_filter_dlg->show();
}

void CaptureFilterEdit::prepareFilter()
{
    QAction *pa = qobject_cast<QAction*>(sender());
    if (! pa || pa->property("capture_filter").toString().isEmpty())
        return;

    QString filter = pa->property("capture_filter").toString();
    setText(filter);

    emit textEdited(filter);
}