[Grey Cat The Flag 2022] flappy-js

1. 개요

브라우저 search in files 문제

 

2. 분석

1) 플로피 버드

접속하면 플로피 버드를 잘 만들어 주셨다.

2) search in files

greyctf 검색했더니 무언가 나옵니다.

 

전체 코드는 이렇습니다.

var game = {
    data: {
        score: 0,
        steps: 0,
        start: !1,
        newHiScore: !1,
        muted: !1
    },
    resources: [{
        name: "bg",
        type: "image",
        src: "data/img/bg.png"
    }, {
        name: "clumsy",
        type: "image",
        src: "data/img/clumsy.png"
    }, {
        name: "pipe",
        type: "image",
        src: "data/img/pipe.png"
    }, {
        name: "logo",
        type: "image",
        src: "data/img/logo.png"
    }, {
        name: "ground",
        type: "image",
        src: "data/img/ground.png"
    }, {
        name: "gameover",
        type: "image",
        src: "data/img/gameover.png"
    }, {
        name: "gameoverbg",
        type: "image",
        src: "data/img/gameoverbg.png"
    }, {
        name: "hit",
        type: "image",
        src: "data/img/hit.png"
    }, {
        name: "getready",
        type: "image",
        src: "data/img/getready.png"
    }, {
        name: "new",
        type: "image",
        src: "data/img/new.png"
    }, {
        name: "share",
        type: "image",
        src: "data/img/share.png"
    }, {
        name: "tweet",
        type: "image",
        src: "data/img/tweet.png"
    }, {
        name: "theme",
        type: "audio",
        src: "data/bgm/"
    }, {
        name: "hit",
        type: "audio",
        src: "data/sfx/"
    }, {
        name: "lose",
        type: "audio",
        src: "data/sfx/"
    }, {
        name: "wing",
        type: "audio",
        src: "data/sfx/"
    }],
    onload: function() {
        return me.video.init(900, 600, {
            wrapper: "screen",
            scale: "auto",
            scaleMethod: "fit"
        }) ? (me.audio.init("mp3,ogg"), void me.loader.preload(game.resources, this.loaded.bind(this))) : void alert("Your browser does not support HTML5 canvas.")
    },
    loaded: function() {
        me.state.set(me.state.MENU, new game.TitleScreen), me.state.set(me.state.PLAY, new game.PlayScreen), me.state.set(me.state.GAME_OVER, new game.GameOverScreen), me.input.bindKey(me.input.KEY.SPACE, "fly", !0), me.input.bindKey(me.input.KEY.M, "mute", !0), me.input.bindPointer(me.input.KEY.SPACE), me.pool.register("clumsy", game.BirdEntity), me.pool.register("pipe", game.PipeEntity, !0), me.pool.register("hit", game.HitEntity, !0), me.pool.register("ground", game.Ground, !0), me.state.change(me.state.MENU)
    }
};
game.BirdEntity = me.Entity.extend({
    init: function(a, b) {
        var c = {};
        c.image = "clumsy", c.width = 85, c.height = 60, this._super(me.Entity, "init", [a, b, c]), this.alwaysUpdate = !0, this.body.gravity = .2, this.maxAngleRotation = Number.prototype.degToRad(-30), this.maxAngleRotationDown = Number.prototype.degToRad(35), this.renderable.addAnimation("flying", [0, 1, 2]), this.renderable.addAnimation("idle", [0]), this.renderable.setCurrentAnimation("flying"), this.body.removeShapeAt(0), this.body.addShape(new me.Ellipse(5, 5, 71, 51)), this.flyTween = new me.Tween(this.pos), this.flyTween.easing(me.Tween.Easing.Exponential.InOut), this.currentAngle = 0, this.angleTween = new me.Tween(this), this.angleTween.easing(me.Tween.Easing.Exponential.InOut), this.endTween = null, this.collided = !1, this.gravityForce = .2
    },
    update: function(a) {
        var b = this;
        if (this.pos.x = 60, !game.data.start) return this._super(me.Entity, "update", [a]);
        if (this.renderable.currentTransform.identity(), me.input.isKeyPressed("fly")) {
            me.audio.play("wing"), this.gravityForce = .2;
            var c = this.pos.y;
            this.angleTween.stop(), this.flyTween.stop(), this.flyTween.to({
                y: c - 72
            }, 50), this.flyTween.start(), this.angleTween.to({
                currentAngle: b.maxAngleRotation
            }, 50).onComplete(function(a) {
                b.renderable.currentTransform.rotate(b.maxAngleRotation)
            }), this.angleTween.start()
        } else this.gravityForce += .2, this.pos.y += me.timer.tick * this.gravityForce, this.currentAngle += Number.prototype.degToRad(3), this.currentAngle >= this.maxAngleRotationDown && (this.renderable.currentTransform.identity(), this.currentAngle = this.maxAngleRotationDown);
        this.renderable.currentTransform.rotate(this.currentAngle), me.Rect.prototype.updateBounds.apply(this);
        var d = -80;
        return this.pos.y <= d || this.collided ? (game.data.start = !1, me.audio.play("lose"), this.endAnimation(), !1) : (me.collision.check(this), !0)
    },
    onCollision: function(a) {
        var b = a.b;
        ("pipe" === b.type || "ground" === b.type) && (me.device.vibrate(500), this.collided = !0), "hit" === b.type && (me.game.world.removeChildNow(b), game.data.steps++, me.audio.play("hit"))
    },
    endAnimation: function() {
        me.game.viewport.fadeOut("#fff", 100);
        var a = this.pos.y;
        this.endTween = new me.Tween(this.pos), this.endTween.easing(me.Tween.Easing.Exponential.InOut), this.flyTween.stop(), this.renderable.currentTransform.identity(), this.renderable.currentTransform.rotate(Number.prototype.degToRad(90));
        var b = me.game.viewport.height - this.renderable.width / 2 - 96;
        this.endTween.to({
            y: a
        }, 1e3).to({
            y: b
        }, 1e3).onComplete(function() {
            me.state.change(me.state.GAME_OVER)
        }), this.endTween.start()
    }
}), game.PipeEntity = me.Entity.extend({
    init: function(a, b) {
        var c = {};
        c.image = this.image = me.loader.getImage("pipe"), c.width = 148, c.height = 1664, c.framewidth = 148, c.frameheight = 1664, this._super(me.Entity, "init", [a, b, c]), this.alwaysUpdate = !0, this.body.gravity = 0, this.body.vel.set(-5, 0), this.type = "pipe"
    },
    update: function(a) {
        return game.data.start ? (this.pos.add(this.body.vel), this.pos.x < -this.image.width && me.game.world.removeChild(this), me.Rect.prototype.updateBounds.apply(this), this._super(me.Entity, "update", [a]), !0) : this._super(me.Entity, "update", [a])
    }
}), game.PipeGenerator = me.Renderable.extend({
    init: function() {
        this._super(me.Renderable, "init", [0, me.game.viewport.width, me.game.viewport.height, 92]), this.alwaysUpdate = !0, this.generate = 0, this.pipeFrequency = 92, this.pipeHoleSize = 1240, this.posX = me.game.viewport.width
    },
    update: function(a) {
        if (this.generate++ % this.pipeFrequency == 0) {
            var b = Number.prototype.random(me.video.renderer.getHeight() - 100, 200),
                c = b - me.game.viewport.height - this.pipeHoleSize,
                d = new me.pool.pull("pipe", this.posX, b),
                e = new me.pool.pull("pipe", this.posX, c),
                f = b - 100,
                g = new me.pool.pull("hit", this.posX, f);
            d.renderable.currentTransform.scaleY(-1), me.game.world.addChild(d, 10), me.game.world.addChild(e, 10), me.game.world.addChild(g, 11)
        }
        this._super(me.Entity, "update", [a])
    }
}), game.HitEntity = me.Entity.extend({
    init: function(a, b) {
        var c = {};
        c.image = this.image = me.loader.getImage("hit"), c.width = 148, c.height = 60, c.framewidth = 148, c.frameheight = 60, this._super(me.Entity, "init", [a, b, c]), this.alwaysUpdate = !0, this.body.gravity = 0, this.updateTime = !1, this.renderable.alpha = 0, this.body.accel.set(-5, 0), this.body.removeShapeAt(0), this.body.addShape(new me.Rect(0, 0, c.width - 30, c.height - 30)), this.type = "hit"
    },
    update: function(a) {
        return this.pos.add(this.body.accel), this.pos.x < -this.image.width && me.game.world.removeChild(this), me.Rect.prototype.updateBounds.apply(this), this._super(me.Entity, "update", [a]), !0
    }
}), game.Ground = me.Entity.extend({
    init: function(a, b) {
        var c = {};
        c.image = me.loader.getImage("ground"), c.width = 900, c.height = 96, this._super(me.Entity, "init", [a, b, c]), this.alwaysUpdate = !0, this.body.gravity = 0, this.body.vel.set(-4, 0), this.type = "ground"
    },
    update: function(a) {
        return this.pos.add(this.body.vel), this.pos.x < -this.renderable.width && (this.pos.x = me.video.renderer.getWidth() - 10), me.Rect.prototype.updateBounds.apply(this), this._super(me.Entity, "update", [a])
    }
}), game.HUD = game.HUD || {}, game.HUD.Container = me.Container.extend({
    init: function() {
        this._super(me.Container, "init"), this.isPersistent = !0, this.collidable = !1, this.z = 1 / 0, this.name = "HUD", this.addChild(new game.HUD.ScoreItem(5, 5))
    }
}), game.HUD.ScoreItem = me.Renderable.extend({
    init: function(a, b) {
        this._super(me.Renderable, "init", [a, b, 10, 10]), this.stepsFont = new me.Font("gamefont", 80, "#000", "center"), this.floating = !0, this.flag = ""
    },
    draw: function(a) {
        game.data.start && me.state.isCurrent(me.state.PLAY) && (this.stepsFont.draw(a, game.data.steps, me.game.viewport.width / 2, 10), game.data.steps >= 31337 && (0 == this.flag.length && (this.flag = genFlag()), this.flagFont = new me.Font("roboto", 35, "#000", "center"), this.flagFont.draw(a, "greyctf{" + this.flag + "}", me.game.viewport.width / 2, 110)))
    }
});
var BackgroundLayer = me.ImageLayer.extend({
        init: function(a, b, c) {
            var d = {};
            d.name = a, d.width = 900, d.height = 600, d.image = a, d.z = b, d.ratio = 1, this._super(me.ImageLayer, "init", [0, 0, d])
        },
        update: function() {
            return me.input.isKeyPressed("mute") && (game.data.muted = !game.data.muted, game.data.muted ? me.audio.disable() : me.audio.enable()), !0
        }
    }),
    genFlag = function() {
        var a = "AzhkZTRlYB0GDT0NAhItAQw4LR4DEzkABjkbAwM5DywDOCFlAhIfEgY5DwMDZgQiAxETNDZkGyYPEzEbAz4lDAIDDz4HZWAmAjsfPAc5Dw0DPx87MDkxAg8RBz4YEQMsAQMDAjQSAyQEAT5o";
        a = atob(a);
        var b = "";
        for (var c in a) b += String.fromCharCode(85 ^ a.charCodeAt(c));
        return b = b.substring(0, b.indexOf("=") + 1), b = atob(b), b = atob(b), b = atob(b), b = atob(b), b = atob(b), b = atob(b)
    };
game.TitleScreen = me.ScreenObject.extend({
    init: function() {
        this._super(me.ScreenObject, "init"), this.font = null, this.ground1 = null, this.ground2 = null, this.logo = null
    },
    onResetEvent: function() {
        me.audio.stop("theme"), game.data.newHiScore = !1, me.game.world.addChild(new BackgroundLayer("bg", 1)), me.input.bindKey(me.input.KEY.ENTER, "enter", !0), me.input.bindKey(me.input.KEY.SPACE, "enter", !0), me.input.bindPointer(me.input.pointer.LEFT, me.input.KEY.ENTER), this.handler = me.event.subscribe(me.event.KEYDOWN, function(a, b, c) {
            "enter" === a && me.state.change(me.state.PLAY)
        }), this.logo = new me.Sprite(me.game.viewport.width / 2, me.game.viewport.height / 2 - 20, {
            image: "logo"
        }), me.game.world.addChild(this.logo, 10);
        me.pool.pull("me.Tween", this.logo.pos).to({
            y: me.game.viewport.height / 2 - 100
        }, 1e3).easing(me.Tween.Easing.Exponential.InOut).start();
        this.ground1 = me.pool.pull("ground", 0, me.video.renderer.getHeight() - 96), this.ground2 = me.pool.pull("ground", me.video.renderer.getWidth(), me.video.renderer.getHeight() - 96), me.game.world.addChild(this.ground1, 11), me.game.world.addChild(this.ground2, 11), me.game.world.addChild(new(me.Renderable.extend({
            init: function() {
                this._super(me.Renderable, "init", [0, 0, 100, 100]), this.text = me.device.touch ? "Tap to start" : 'PRESS SPACE OR CLICK LEFT MOUSE BUTTON TO START \n											PRESS "M" TO MUTE SOUND', this.font = new me.Font("gamefont", 20, "#000")
            },
            draw: function(a) {
                var b = this.font.measureText(a, this.text),
                    c = me.game.viewport.width / 2 - b.width / 2,
                    d = me.game.viewport.height / 2 + 50;
                this.font.draw(a, this.text, c, d)
            }
        })), 12)
    },
    onDestroyEvent: function() {
        me.event.unsubscribe(this.handler), me.input.unbindKey(me.input.KEY.ENTER), me.input.unbindKey(me.input.KEY.SPACE), me.input.unbindPointer(me.input.pointer.LEFT), this.ground1 = null, this.ground2 = null, me.game.world.removeChild(this.logo), this.logo = null
    }
}), game.PlayScreen = me.ScreenObject.extend({
    init: function() {
        me.audio.play("theme", !0);
        var a = -1 !== me.device.ua.indexOf("Firefox") ? .3 : .5;
        me.audio.setVolume(a), this._super(me.ScreenObject, "init")
    },
    onResetEvent: function() {
        me.game.reset(), me.audio.stop("theme"), game.data.muted || me.audio.play("theme", !0), me.input.bindKey(me.input.KEY.SPACE, "fly", !0), game.data.score = 0, game.data.steps = 0, game.data.start = !1, game.data.newHiscore = !1, me.game.world.addChild(new BackgroundLayer("bg", 1)), this.ground1 = me.pool.pull("ground", 0, me.game.viewport.height - 96), this.ground2 = me.pool.pull("ground", me.game.viewport.width, me.game.viewport.height - 96), me.game.world.addChild(this.ground1, 11), me.game.world.addChild(this.ground2, 11), this.HUD = new game.HUD.Container, me.game.world.addChild(this.HUD, 11), this.bird = me.pool.pull("clumsy", 60, me.game.viewport.height / 2 - 100), me.game.world.addChild(this.bird, 10), me.input.bindPointer(me.input.pointer.LEFT, me.input.KEY.SPACE), this.getReady = new me.Sprite(me.game.viewport.width / 2, me.game.viewport.height / 2, {
            image: "getready"
        }), me.game.world.addChild(this.getReady, 11);
        var a = this;
        new me.Tween(this.getReady).to({
            alpha: 0
        }, 2e3).easing(me.Tween.Easing.Linear.None).onComplete(function() {
            game.data.start = !0, me.game.world.addChild(new game.PipeGenerator, 0), me.game.world.removeChild(a.getReady)
        }).start()
    },
    onDestroyEvent: function() {
        me.audio.stopTrack("theme"), this.HUD = null, this.bird = null, this.ground1 = null, this.ground2 = null, me.input.unbindKey(me.input.KEY.SPACE), me.input.unbindPointer(me.input.pointer.LEFT)
    }
}), game.GameOverScreen = me.ScreenObject.extend({
    init: function() {
        this.savedData = null, this.handler = null
    },
    onResetEvent: function() {
        this.savedData = {
            score: game.data.score,
            steps: game.data.steps
        }, me.save.add(this.savedData), me.save.topSteps || me.save.add({
            topSteps: game.data.steps
        }), game.data.steps > me.save.topSteps && (me.save.topSteps = game.data.steps, game.data.newHiScore = !0), me.input.bindKey(me.input.KEY.ENTER, "enter", !0), me.input.bindKey(me.input.KEY.SPACE, "enter", !1), me.input.bindPointer(me.input.pointer.LEFT, me.input.KEY.ENTER), this.handler = me.event.subscribe(me.event.KEYDOWN, function(a, b, c) {
            "enter" === a && me.state.change(me.state.MENU)
        }), me.game.world.addChild(new me.Sprite(me.game.viewport.width / 2, me.game.viewport.height / 2 - 100, {
            image: "gameover"
        }), 12);
        var a = new me.Sprite(me.game.viewport.width / 2, me.game.viewport.height / 2, {
            image: "gameoverbg"
        });
        if (me.game.world.addChild(a, 10), me.game.world.addChild(new BackgroundLayer("bg", 1)), this.ground1 = me.pool.pull("ground", 0, me.game.viewport.height - 96), this.ground2 = me.pool.pull("ground", me.game.viewport.width, me.video.renderer.getHeight() - 96), me.game.world.addChild(this.ground1, 11), me.game.world.addChild(this.ground2, 11), game.data.newHiScore) {
            var b = new me.Sprite(a.width / 2, a.height / 2, {
                image: "new"
            });
            me.game.world.addChild(b, 12)
        }
        this.dialog = new(me.Renderable.extend({
            init: function() {
                this._super(me.Renderable, "init", [0, 0, me.game.viewport.width / 2, me.game.viewport.height / 2]), this.font = new me.Font("gamefont", 40, "black", "left"), this.steps = "Steps: " + game.data.steps.toString(), this.topSteps = "Higher Step: " + me.save.topSteps.toString()
            },
            draw: function(a) {
                var b = this.font.measureText(a, this.steps);
                this.font.measureText(a, this.topSteps), this.font.measureText(a, this.score);
                this.font.draw(a, this.steps, me.game.viewport.width / 2 - b.width / 2 - 60, me.game.viewport.height / 2), this.font.draw(a, this.topSteps, me.game.viewport.width / 2 - b.width / 2 - 60, me.game.viewport.height / 2 + 50)
            }
        })), me.game.world.addChild(this.dialog, 12)
    },
    onDestroyEvent: function() {
        me.event.unsubscribe(this.handler), me.input.unbindKey(me.input.KEY.ENTER), me.input.unbindKey(me.input.KEY.SPACE), me.input.unbindPointer(me.input.pointer.LEFT), this.ground1 = null, this.ground2 = null, this.font = null, me.audio.stop("theme")
    }
});

3. exploit

1) genFlag() 

플래그 생성하는 함수 같습니다.

2) 문자열 합성

백틱 사용해서 제출하기 좋게 만듭니다.

`greyctf{${genFlag()}}`