diff options
Diffstat (limited to 'src/m_im/ImSettingsPage.cpp')
| -rw-r--r-- | src/m_im/ImSettingsPage.cpp | 300 |
1 files changed, 300 insertions, 0 deletions
diff --git a/src/m_im/ImSettingsPage.cpp b/src/m_im/ImSettingsPage.cpp new file mode 100644 index 0000000..a2f1d84 --- /dev/null +++ b/src/m_im/ImSettingsPage.cpp @@ -0,0 +1,300 @@ +/** + * Copyright (C) 2021-2024 Saturneric <[email protected]> + * + * This file is part of GpgFrontend. + * + * GpgFrontend is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * GpgFrontend is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with GpgFrontend. If not, see <https://www.gnu.org/licenses/>. + * + * The initial version of the source code is inherited from + * the gpg4usb project, which is under GPL-3.0-or-later. + * + * All the source code of GpgFrontend was modified and released by + * Saturneric <[email protected]> starting on May 12, 2021. + * + * SPDX-License-Identifier: GPL-3.0-or-later + * + */ + +#include "ImSettingsPage.h" + +#include <GFSDK.hpp> + +#include <QtWidgets> + +#include "ImCodec.h" +#include "ImToken.h" + +namespace { + +/// Typing pause before the (memory-hard) fingerprint derivation is worth doing. +constexpr int kFingerprintDebounceMs = 500; + +/// A phrase pasted from a chat app may arrive wrapped across lines; it is one +/// unbroken word, so every kind of whitespace simply comes back out. +auto CleanPhrase(const QString& text) -> QString { + QString out; + out.reserve(text.size()); + for (const auto c : text) { + if (!c.isSpace()) out.append(c); + } + return out; +} + +/// Starts from the widget's own font on purpose, so the token and the +/// fingerprint keep the size of the page around them and only change family. +auto MonospaceFont(const QWidget* widget) -> QFont { + auto font = widget->font(); + font.setFamilies( + QFontDatabase::systemFont(QFontDatabase::FixedFont).families()); + return font; +} + +auto Tr(const char* text) -> QString { + return QCoreApplication::translate("GTrC", text); +} + +/// Where the phrase lives: the module's own secret store. +constexpr auto kPhraseKey = "book_phrase"; + +} // namespace + +ImSettingsPage::ImSettingsPage(QWidget* parent) : QWidget(parent) { + // ---- the phrase itself ------------------------------------------------- + // The Message Book phrase whitens every instant-messaging token: its bytes + // derive the shuffle + XOR that hide the message, so without the same phrase + // a token is indistinguishable from random text. + auto* book_box = new QGroupBox(Tr("Message Book Phrase"), this); + auto* book_layout = new QVBoxLayout(book_box); + + auto* intro = new QLabel( + Tr("A long secret you share with one friend. It makes your messages look " + "like random text, so nobody can tell they are PGP at all. You and " + "your friend must use exactly the same phrase."), + book_box); + intro->setWordWrap(true); + book_layout->addWidget(intro); + + // A generated phrase is 256 characters, far too long for a one-line field, + // so it gets a wrapping box the user can see and select in full. + phrase_edit_ = new QPlainTextEdit(book_box); + phrase_edit_->setFont(MonospaceFont(this)); + phrase_edit_->setLineWrapMode(QPlainTextEdit::WidgetWidth); + phrase_edit_->setPlaceholderText( + Tr("No phrase set. Messages use the built-in default book.")); + phrase_edit_->setVerticalScrollBarPolicy(Qt::ScrollBarAsNeeded); + phrase_edit_->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff); + phrase_edit_->setFixedHeight(phrase_edit_->fontMetrics().lineSpacing() * 5 + + 12); + connect(phrase_edit_, &QPlainTextEdit::textChanged, this, [this]() { + if (syncing_ || !revealed_) return; + set_phrase(CleanPhrase(phrase_edit_->toPlainText())); + }); + book_layout->addWidget(phrase_edit_); + + phrase_state_label_ = new QLabel(book_box); + phrase_state_label_->setWordWrap(true); + + // One click gives a phrase no one will ever guess; the user's only job is to + // get it to their friend privately. + auto* generate_button = new QPushButton(Tr("Generate"), book_box); + generate_button->setToolTip( + Tr("Create a new random phrase. Share it with your friend so you both " + "use the same one.")); + connect(generate_button, &QPushButton::clicked, this, [this]() { + const auto phrase = ImToken::GeneratePhrase(); + if (phrase.isEmpty()) return; + set_phrase(phrase); + // A fresh phrase has to be seen to be shared. + set_revealed(true); + }); + + reveal_button_ = new QPushButton(Tr("Show"), book_box); + reveal_button_->setToolTip(Tr("Show or hide the phrase.")); + connect(reveal_button_, &QPushButton::clicked, this, + [this]() { set_revealed(!revealed_); }); + + auto* copy_button = new QPushButton(Tr("Copy"), book_box); + copy_button->setToolTip(Tr("Copy the phrase to the clipboard.")); + connect(copy_button, &QPushButton::clicked, this, + [this]() { QApplication::clipboard()->setText(phrase_); }); + + auto* paste_button = new QPushButton(Tr("Paste"), book_box); + paste_button->setToolTip( + Tr("Replace the phrase with the one on the clipboard.")); + connect(paste_button, &QPushButton::clicked, this, [this]() { + const auto text = CleanPhrase(QApplication::clipboard()->text()); + if (!text.isEmpty()) set_phrase(text); + }); + + auto* clear_button = new QPushButton(Tr("Clear"), book_box); + clear_button->setToolTip( + Tr("Remove the phrase and fall back to the default book.")); + connect(clear_button, &QPushButton::clicked, this, + [this]() { set_phrase({}); }); + + // The buttons keep their natural width on the right; the state line gets a + // row of its own so it never squeezes them into a narrow column. + auto* button_row = new QHBoxLayout(); + button_row->setContentsMargins(0, 0, 0, 0); + button_row->addStretch(1); + button_row->addWidget(generate_button); + button_row->addWidget(reveal_button_); + button_row->addWidget(copy_button); + button_row->addWidget(paste_button); + button_row->addWidget(clear_button); + book_layout->addWidget(phrase_state_label_); + book_layout->addLayout(button_row); + + // ---- checking both sides agree ----------------------------------------- + auto* check_box = new QGroupBox(Tr("Book Fingerprint"), this); + auto* check_layout = new QVBoxLayout(check_box); + + auto* check_note = new QLabel( + Tr("A short code made from your phrase. Read it out with your friend to " + "be sure you both have the same one. Unlike the phrase, this code is " + "safe to say out loud."), + check_box); + check_note->setWordWrap(true); + check_layout->addWidget(check_note); + + fingerprint_label_ = new QLabel(check_box); + auto fpr_font = MonospaceFont(this); + fpr_font.setBold(true); + fpr_font.setPointSize(fpr_font.pointSize() + 2); + fingerprint_label_->setFont(fpr_font); + fingerprint_label_->setTextInteractionFlags(Qt::TextSelectableByMouse); + + auto* copy_fpr_button = new QPushButton(Tr("Copy"), check_box); + copy_fpr_button->setToolTip(Tr("Copy the fingerprint to the clipboard.")); + connect(copy_fpr_button, &QPushButton::clicked, this, + [this]() { QApplication::clipboard()->setText(fingerprint_); }); + + auto* fpr_row = new QHBoxLayout(); + fpr_row->setContentsMargins(0, 0, 0, 0); + fpr_row->addWidget(fingerprint_label_); + fpr_row->addStretch(1); + fpr_row->addWidget(copy_fpr_button); + check_layout->addLayout(fpr_row); + + auto* storage_note = new QLabel( + Tr("The phrase is stored in the encrypted cache, never in the settings " + "file. Send it to your friend over a private channel."), + this); + storage_note->setWordWrap(true); + + auto* layout = new QVBoxLayout(this); + layout->addWidget(book_box); + layout->addWidget(check_box); + layout->addWidget(storage_note); + layout->addStretch(1); + setLayout(layout); + + // Deriving a fingerprint costs one Argon2id (64 MiB), so wait for a pause in + // typing rather than doing it per keystroke. + fingerprint_timer_ = new QTimer(this); + fingerprint_timer_->setSingleShot(true); + fingerprint_timer_->setInterval(kFingerprintDebounceMs); + connect(fingerprint_timer_, &QTimer::timeout, this, + &ImSettingsPage::start_fingerprint_update); + + ImSettingsPage::LoadSettings(); +} + +void ImSettingsPage::LoadSettings() { + set_phrase(ImBookPhrase()); + // Nothing to hide when there is no phrase yet. + set_revealed(phrase_.isEmpty()); +} + +auto ImSettingsPage::ApplySettings() -> bool { + if (phrase_ != ImBookPhrase()) ImSetBookPhrase(phrase_); + return true; +} + +void ImSettingsPage::set_revealed(bool revealed) { + revealed_ = revealed; + reveal_button_->setText(revealed ? Tr("Hide") : Tr("Show")); + + const QScopedValueRollback<bool> guard(syncing_, true); + // Masked, the box is a placeholder rather than an editor: editing dots + // would only destroy the phrase behind them. + phrase_edit_->setReadOnly(!revealed); + phrase_edit_->setPlainText(revealed || phrase_.isEmpty() + ? phrase_ + : QString(phrase_.size(), QChar(u'•'))); +} + +void ImSettingsPage::set_phrase(const QString& phrase) { + phrase_ = phrase; + + if (phrase_edit_->toPlainText() != phrase_) { + const QScopedValueRollback<bool> guard(syncing_, true); + phrase_edit_->setPlainText(phrase_); + } + + phrase_state_label_->setText( + phrase_.isEmpty() ? Tr("No phrase set. Using the built-in default.") + : Tr("Phrase set. %1 characters.").arg(phrase_.size())); + + schedule_fingerprint_update(); +} + +void ImSettingsPage::schedule_fingerprint_update() { + // Invalidate any derivation already in flight: its result is for an older + // phrase and must not overwrite what we are about to compute. + ++fingerprint_request_; + set_fingerprint({}); + fingerprint_label_->setText(Tr("Calculating…")); + fingerprint_timer_->start(); +} + +void ImSettingsPage::start_fingerprint_update() { + const auto phrase = phrase_; + const auto request = fingerprint_request_; + QPointer<ImSettingsPage> self(this); + + // One Argon2id (64 MiB): off the GUI thread, back to it with the answer, + // and dropped if the page is gone or the phrase changed meanwhile. + QThreadPool::globalInstance()->start([self, phrase, request]() { + const auto result = ImToken::BookFingerprintOf(phrase); + if (self.isNull()) return; + QMetaObject::invokeMethod( + self.data(), + [self, result, request]() { + if (self.isNull() || self->fingerprint_request_ != request) return; + self->set_fingerprint(result); + }, + Qt::QueuedConnection); + }); +} + +void ImSettingsPage::set_fingerprint(const QString& fingerprint) { + fingerprint_ = fingerprint; + fingerprint_label_->setText(fingerprint.isEmpty() ? QString("...") + : fingerprint); +} + + +auto ImBookPhrase() -> QString { + return ImCodec::DecodePhraseBlob( + gf::sdk::CacheText(GFModuleSdkContext(), GF_STORE_SECURE_DURABLE, + kPhraseKey) + .toUtf8()); +} + +void ImSetBookPhrase(const QString& phrase) { + gf::sdk::SetCacheText( + GFModuleSdkContext(), GF_STORE_SECURE_DURABLE, kPhraseKey, + QString::fromUtf8(ImCodec::EncodePhraseBlob(phrase))); +} |