cpp-lib/zerostoragecaptcha.cpp

275 lines
8.5 KiB
C++

// 2022 (c) GPLv3, acetone at i2pmail.org
// Zero Storage Captcha
/*
* Copyright (c) 2014 Omkar Kanase
* QtCaptcha: https://github.com/omkar-developer/QtCaptcha
*
* This software is provided 'as-is', without any express or implied
* warranty. In no event will the authors be held liable for any damages
* arising from the use of this software.
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked as such, and must not be
* misrepresented as being the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/
#include "zerostoragecaptcha.h"
#include <QTime>
#include <QBuffer>
#include <QDebug>
#include <QPainter>
#include <random>
bool ZeroStorageCaptcha::m_onlyNumbers = false;
ZeroStorageCaptcha::ZeroStorageCaptcha()
{
if (not ZeroStorageCaptchaCrypto::TimeToken::inited()) ZeroStorageCaptchaCrypto::TimeToken::init();
m_hmod1 = 0.0;
m_hmod2 = 0.0;
m_vmod1 = 0.0;
m_vmod2 = 0.0;
m_font.setStyleStrategy(QFont::ForceOutline);
m_font.setPointSize(50);
m_font.setBold(true);
m_font.setLetterSpacing(QFont::PercentageSpacing, QFont::SemiCondensed);
m_captchaImage = QImage(200, 100, QImage::Format_RGB32);
if (QTime::currentTime().msec() % 2 == 0)
{
m_backColor = Qt::GlobalColor::white;
m_fontColor = Qt::GlobalColor::black;
}
else
{
m_backColor = Qt::GlobalColor::black;
m_fontColor = Qt::GlobalColor::white;
}
m_padding = 5;
setDifficulty(3);
m_captchaText = "NOTSET";
qsrand(static_cast<uint>(QTime::currentTime().msec())); // randomize
}
bool ZeroStorageCaptcha::validate(const QString &answer, const QString &token)
{
return ZeroStorageCaptchaCrypto::KeyHolder::validateCaptchaAnswer(answer, token);
}
ZeroStorageCaptchaContainer ZeroStorageCaptcha::getCaptcha(int length, int difficulty)
{
ZeroStorageCaptcha c;
c.setDifficulty(difficulty);
c.generateText(length);
return ZeroStorageCaptchaContainer (c.captchaPngByteArray(), c.captchaToken(), c.captchaText());
}
QString ZeroStorageCaptcha::captchaToken() const
{
return ZeroStorageCaptchaCrypto::KeyHolder::captchaSecretLine(m_captchaText);
}
QByteArray ZeroStorageCaptcha::captchaPngByteArray() const
{
QByteArray data;
QBuffer buff(&data);
m_captchaImage.save(&buff, "PNG");
return data;
}
void ZeroStorageCaptcha::updateCaptcha()
{
QPainterPath path;
QFontMetrics fm(m_font);
path.addText(m_vmod2 + m_padding, m_hmod2 - m_padding + fm.height(), font(), captchaText());
qreal sinrandomness = (static_cast<qreal>(qrand()) / RAND_MAX) * 5.0;
for (int i = 0; i < path.elementCount(); ++i)
{
const QPainterPath::Element& el = path.elementAt(i);
qreal y = el.y + sin(el.x / m_hmod1 + sinrandomness) * m_hmod2;
qreal x = el.x + sin(el.y / m_vmod1 + sinrandomness) * m_vmod2;
path.setElementPositionAt(i, x, y);
}
m_captchaImage = QImage(static_cast<int>(fm.horizontalAdvance(m_captchaText) + m_vmod2 * 2 + m_padding * 2),
static_cast<int>(fm.height() + m_hmod2 * 2 + m_padding * 2), QImage::Format_RGB32);
m_captchaImage.fill(backColor());
QPainter painter;
painter.begin(&m_captchaImage);
painter.setPen(Qt::NoPen);
painter.setBrush(fontColor());
painter.setRenderHint(QPainter::Antialiasing);
painter.drawPath(path);
if (m_drawLines)
{
painter.setPen(QPen(Qt::black, m_lineWidth));
for (int i = 0; i < m_lineCount; i++)
{
int x1 = static_cast<int>((static_cast<qreal>(qrand()) / RAND_MAX) * m_captchaImage.width());
int y1 = static_cast<int>((static_cast<qreal>(qrand()) / RAND_MAX) * m_captchaImage.height());
int x2 = static_cast<int>((static_cast<qreal>(qrand()) / RAND_MAX) * m_captchaImage.width());
int y2 = static_cast<int>((static_cast<qreal>(qrand()) / RAND_MAX) * m_captchaImage.height());
painter.drawLine(x1, y1, x2, y2);
}
painter.setPen(Qt::NoPen);
}
if (m_drawEllipses)
{
for (int i = 0; i < m_ellipseCount; i++)
{
int x1 = static_cast<int>(m_ellipseMaxRadius / 2.0 + (static_cast<qreal>(qrand()) / RAND_MAX) * (m_captchaImage.width() - m_ellipseMaxRadius));
int y1 = static_cast<int>(m_ellipseMaxRadius / 2.0 + (static_cast<qreal>(qrand()) / RAND_MAX) * (m_captchaImage.height() - m_ellipseMaxRadius));
int rad1 = static_cast<int>(m_ellipseMinRadius + (static_cast<qreal>(qrand()) / RAND_MAX) * (m_ellipseMaxRadius - m_ellipseMinRadius));
int rad2 = static_cast<int>(m_ellipseMinRadius + (static_cast<qreal>(qrand()) / RAND_MAX) * (m_ellipseMaxRadius - m_ellipseMinRadius));
if (backColor() == Qt::GlobalColor::black)
{
painter.setBrush(fontColor());
painter.setCompositionMode(QPainter::CompositionMode_Difference);
} else {
painter.setBrush(backColor());
painter.setCompositionMode(QPainter::CompositionMode_Exclusion);
}
painter.drawEllipse(QPoint(x1, y1), rad1, rad2);
}
}
if (m_drawNoise)
{
for (int i = 0; i < m_noiseCount; i++)
{
int x1 = static_cast<int>(static_cast<qreal>(qrand()) / RAND_MAX * m_captchaImage.width());
int y1 = static_cast<int>(static_cast<qreal>(qrand()) / RAND_MAX * m_captchaImage.height());
QColor col = backColor() == Qt::GlobalColor::black ? Qt::GlobalColor::white : Qt::GlobalColor::black;
painter.setPen(QPen(col, m_noisePointSize));
painter.setCompositionMode(QPainter::CompositionMode_SourceOver);
painter.drawPoint(x1, y1);
}
}
painter.end();
}
void ZeroStorageCaptcha::setSinDeform(qreal hAmplitude, qreal hFrequency, qreal vAmplitude, qreal vFrequency)
{
m_hmod1 = hFrequency;
m_hmod2 = hAmplitude;
m_vmod1 = vFrequency;
m_vmod2 = vAmplitude;
}
void ZeroStorageCaptcha::setDifficulty(int val)
{
if (val < 0 or val > 5)
{
qInfo().noquote() << QString(__PRETTY_FUNCTION__) << "Min difficulty is 0, maximal is 5";
}
if (val < 1)
{
m_drawLines = false;
m_drawEllipses = false;
m_drawNoise = false;
setSinDeform(10, 10, 5, 20);
}
else if (val == 1)
{
m_drawLines = true;
m_lineWidth = 3;
m_lineCount = 5;
m_drawEllipses = false;
m_drawNoise = false;
setSinDeform(10, 15, 5, 20);
}
else if (val == 2)
{
m_drawLines = true;
m_lineWidth = 2;
m_lineCount = 5;
m_drawEllipses = true;
m_ellipseCount = 1;
m_ellipseMinRadius = 20;
m_ellipseMaxRadius = 40;
m_drawNoise = false;
setSinDeform(10, 15, 5, 15);
}
else if (val == 3)
{
m_drawLines = true;
m_lineWidth = 2;
m_lineCount = 3;
m_drawEllipses = true;
m_ellipseCount = 1;
m_ellipseMinRadius = 20;
m_ellipseMaxRadius = 50;
m_drawNoise = true;
m_noiseCount = 100;
m_noisePointSize = 3;
setSinDeform(8, 13, 5, 15);
}
else if (val == 4)
{
m_drawLines = true;
m_lineWidth = 3;
m_lineCount = 5;
m_drawEllipses = true;
m_ellipseCount = 2;
m_ellipseMinRadius = 20;
m_ellipseMaxRadius = 40;
m_drawNoise = true;
m_noiseCount = 100;
m_noisePointSize = 3;
setSinDeform(8, 13, 5, 15);
}
else
{
m_drawLines = true;
m_lineWidth = 4;
m_lineCount = 7;
m_drawEllipses = true;
m_ellipseCount = 1;
m_ellipseMinRadius = 20;
m_ellipseMaxRadius = 40;
m_drawNoise = true;
m_noiseCount = 200;
m_noisePointSize = 3;
setSinDeform(8, 10, 5, 10);
}
}
void ZeroStorageCaptcha::generateText(int length)
{
if (length <= 0)
{
qInfo() << QString(__PRETTY_FUNCTION__) << "Invalid number of characters. Set to 5.";
length = 5;
}
m_captchaText = ZeroStorageCaptchaCrypto::random(length, m_onlyNumbers);
updateCaptcha();
}