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  • How do produce a "mucus spreading" effect in a 2D environment?

    - by nathan
    Here is an example of such a mucus spreading. The substance is spread around the source (in this example, the source would be the main alien building). The game is starcraft, the purple substance is called creep. How this kind of substance spreading would be achieved in a top down 2D environment? Recalculating the substance progression and regenerate the effect on the fly each frame or rather use a large collection of tiles or something else?

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  • Can i add friction in air?

    - by Diken
    I have issue regarding speed in air. When i jump and move simultaneously that time speed of player increase.For jump i am using impuls and for movement i am using force.I want to slow speed when player is in air. Thanks in advance Following is my update method ih HUDLayer -(void)update:(ccTime)dt :(b2Body *)ballBody :(CCSprite *)player1 :(b2World *)world { if (moveRight.active==YES) { ballBody->SetActive(true); b2Vec2 locationworld=b2Vec2(maxSpeed,0); double mass=ballBody->GetMass(); ballBody->ApplyForce(mass*locationworld, ballBody->GetWorldCenter()); // ballBody->SetLinearDamping(1.2f); } else if(moveLeft.active==YES) { ballBody->SetActive(true); b2Vec2 locationworld=b2Vec2(-10,0); double mass=ballBody->GetMass(); ballBody->ApplyForce(mass*locationworld, ballBody->GetWorldCenter()); // ballBody->SetLinearDamping(1.2f); } } Following is jump -(void)jump:(b2Body*)ballBody:(ccTime)dt:(BOOL)touch { if (touch) { if (jumpSprte.active==YES) { ballBody->SetActive(true); b2Vec2 locationWorld; //locationWorld=b2Vec2(0.0f,98.0f); locationWorld=b2Vec2(0,32); // double mass=ballBody->GetMass(); ballBody->ApplyLinearImpulse(locationWorld, ballBody->GetWorldCenter()); // ballBody->ApplyForce(mass*locationWorld, ballBody->GetWorldCenter()); ballBody->SetLinearDamping(1.2f); } } } So where i apply logic??

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  • How to auto apply drag and drop effect to dynamically added element ?

    - by Relax
    I use jquery ui to apply a drag and drop effect on a serial of DIVs, for example: <div class="draggable">...</div> <div class="draggable">...</div> <div class="draggable">...</div> <div class="draggable"> this DIV was dynamically added, not draggable </div> The problem is dynamically added DIVs won't have this effect applied, how can i apply this effect on new members too?

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  • Where is rebol fill-pen documented (to get glow effect on a round rectangle) ?

    - by Rebol Tutorial
    There is some discussion here about fill-pen http://www.mail-archive.com/[email protected]/msg02019.html But I can't see documentation about cubic, diamond, etc... effect for fill-pen in rebol's official doc ? I'm trying to draw some round rectangle with glowing effect but don't really understand the parameters I'm playing with so I can't get exactly what I'd like (I'd like the glow effect starting from the center not from the dark left top corner): view layout [ box 278x185 effect [ ; default box face size is 100x100 draw [ anti-alias on ; information for the next draw element (not required) line-width 2.5 ; number of pixels in width of the border pen black ; color of the edge of the next draw element ; fill pen is a little complex: ;fill-pen 10x10 0 90 0 1 1 0.0.0 255.0.0 255.0.255 fill-pen radial 20x20 5 55 5 5 10 0.0.0 55.0.5 55.0.5 ; the draw element box ; another box drawn as an effect 15 ; size of rounding in pixels 0x0 ; upper left corner 278x170 ; lower right corner ] ] ]

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  • Will a Wubi install of Ubuntu effect my Windows installation in anyway? [closed]

    - by Oddysee
    Possible Duplicate: What are the benefits of a disk install vs. Wubi? And can I migrate my settings easily? Having never tried a Linux OS before, I want to dabble and take a look at one. Ubuntu seems like a good distro to go with (due to how popular it is) and I want to use Wubi to try it out. I just wanted to know if anything I do while trying out Ubuntu will effect my Windows Installation or the files pertaining to it in anyway? If so, is it potentially Windows breaking?

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  • How do I implement a "sliding out of / into" effect on a settings menu similar to that in Angry Birds?

    - by VictorB
    I'm trying to implement a settings menu component similar to that in Angry Birds - a button control that makes an options menu slide out of it and back into it when clicked on. I use scene2d.ui to build the UI components: a Button in a Table to implement the button control, a Table to implement the options menu, and a Stack to lay these out one on top of the other and at this moment I have the following behavior: When the user hits the button control for the first time, then the alpha of the table component is set to 1; When the user hits the button control the second time, then the alpha of the table component is set to 0; And so on. Any ideas how I can get the sliding out of and into effect on user clicks with libgdx? Similar to what Angry Birds provides. Maybe using the TweenEngine, actions, interpolations, combinations of these? Thanks in advance.

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  • What is the effect of creating unit tests during development on time to develop as well as time spent in maintenance activities?

    - by jgauffin
    I'm a consultant and I am going to introduce unit tests to all developers at my client site. My goal is to ensure that all new applications should have unit tests for all classes created. The client has a problem with high maintenance costs from fixing bugs in their existing applications. Their applications have a life span from between 5-15 years in which they continuously add new features. I'm quite confident that they will benefit greatly from starting with unit tests. I'm interested in the effect of unit tests on the time and cost of development: How much time will writing unit tests as part of the development process add? How much time will be saved in maintenance activities (testing and debugging) by having good unit tests?

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  • Does using a country domain (TLD) negatively effect a site's search ranking if the site content isn't country specific?

    - by Alexizamerican
    I have a website in which the content is not country specific. The TLD is currently .it but the company is hosted and based in the United States. I'm wondering if a .it domain will negatively effect the site's search rankings. Is it better to use a .com TLD? For example (I don't actually own these domains), would the domain love.it have a worse ranking than loveit.com? (Assuming the content of the sites is the same) I've been searching everywhere for an answer with not much luck. Any advice would be very helpful.

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  • Why is a fully transparent pixel still rendered?

    - by Mr Bell
    I am trying to make a pixel shader that achieves an effect similar to this video http://www.youtube.com/watch?v=f1uZvurrhig&feature=related My basic idea is render the scene to a temp render target then Render the previously rendered image with a slight fade on to another temp render target Draw the current scene on top of that Draw the results on to a render target that persists between draws Draw the results on to the screen But I am having problems with the fading portion. If I have my pixel shader return a color with its A component set to 0, shouldn't that basically amount to drawing nothing? (Assuming that sprite batch blend mode is set to AlphaBlend) To test this I have my pixel shader return a transparent red color. Instead of nothing being drawn, it draws a partially transparent red box. I hope that my question makes sense, but if it doesnt please ask me to clarify Here is the drawing code public override void Draw(GameTime gameTime) { GraphicsDevice.SamplerStates[1] = SamplerState.PointWrap; drawImageOnClearedRenderTarget(presentationTarget, tempRenderTarget, fadeEffect); drawImageOnRenderTarget(sceneRenderTarget, tempRenderTarget); drawImageOnClearedRenderTarget(tempRenderTarget, presentationTarget); GraphicsDevice.SetRenderTarget(null); drawImage(backgroundTexture); drawImage(presentationTarget); base.Draw(gameTime); } private void drawImage(Texture2D image, Effect effect = null) { spriteBatch.Begin(0, BlendState.AlphaBlend, SamplerState.PointWrap, null, null, effect); spriteBatch.Draw(image, new Rectangle(0, 0, width, height), Color.White); spriteBatch.End(); } private void drawImageOnRenderTarget(Texture2D image, RenderTarget2D target, Effect effect = null) { GraphicsDevice.SetRenderTarget(target); drawImage(image, effect); } private void drawImageOnClearedRenderTarget(Texture2D image, RenderTarget2D target, Effect effect = null) { GraphicsDevice.SetRenderTarget(target); GraphicsDevice.Clear(Color.Transparent); drawImage(image, effect); } Here is the fade pixel shader sampler TextureSampler : register(s0); float4 PixelShaderFunction(float2 texCoord : TEXCOORD0) : COLOR0 { float4 c = 0; c = tex2D(TextureSampler, texCoord); //c.a = clamp(c.a - 0.05, 0, 1); c.r = 1; c.g = 0; c.b = 0; c.a = 0; return c; } technique Fade { pass Pass1 { PixelShader = compile ps_2_0 PixelShaderFunction(); } }

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  • How to make unit selection circles merge?

    - by MaT
    I would like to know how to make this effect of merged circle selection. Here are images to illustrate: Basically I'm looking for this effect: How the merge effect of the circles can be achieved ? I didn't found any explanation concerning this effect. I know that to project those texture I can develop a decal system but I don't know how to create the merging effect. If possible, I'm looking for purely shaders solution.

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  • Why i can not load a simple pixel shader effect (. fx) file in xna?

    - by Mehdi Bugnard
    I just want to load a simple *.fx file into my project to make a (pixel shader) effect. But whenever I try to compile my project, I get the following error in visual studio Error List: Errors compiling .. ID3DXEffectCompiler: There were no techniques ID3DXEffectCompiler: Compilation failed I already searched on google and found many people with the same problem. And I realized that it was a problem of encoding. With the return lines unrecognized '\ n' . I tried to copy and paste to notepad and save as with ASCII or UTF8 encoding. But the result is always the same. Do you have an idea please ? Thanks a looot :-) Here is my [.fx] file : sampler BaseTexture : register(s0); sampler MaskTexture : register(s1) { addressU = Clamp; addressV = Clamp; }; //All of these variables are pixel values //Feel free to replace with float2 variables float MaskLocationX; float MaskLocationY; float MaskWidth; float MaskHeight; float BaseTextureLocationX; //This is where your texture is to be drawn float BaseTextureLocationY; //texCoord is different, it is the current pixel float BaseTextureWidth; float BaseTextureHeight; float4 main(float2 texCoord : TEXCOORD0) : COLOR0 { //We need to calculate where in terms of percentage to sample from the MaskTexture float maskPixelX = texCoord.x * BaseTextureWidth + BaseTextureLocationX; float maskPixelY = texCoord.y * BaseTextureHeight + BaseTextureLocationY; float2 maskCoord = float2((maskPixelX - MaskLocationX) / MaskWidth, (maskPixelY - MaskLocationY) / MaskHeight); float4 bitMask = tex2D(MaskTexture, maskCoord); float4 tex = tex2D(BaseTexture, texCoord); //It is a good idea to avoid conditional statements in a pixel shader if you can use math instead. return tex * (bitMask.a); //Alternate calculation to invert the mask, you could make this a parameter too if you wanted //return tex * (1.0 - bitMask.a); }

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  • Image 1 becomes image 2 with sliding effect from left to right?

    - by Paul
    I would like to show a second image appearing while a "door" is closing on my character. I've got my character in the middle of the screen and a door coming from the left. When the door passes my character, I would like to have this second image appearing little by little. So far, I've gotten by with fadingOut the character and then fadingIn my second image of the character at the same position when the door is completely closed, but I would like to have both of them at the same time. (the effect that image 1 becomes image 2 when the door is sliding from left to right). Would you know how to do this with Cocos2d? Here are the images : at first, the character is blue, and the door is coming from the left : Then, behind the black door, the character becomes red, but only behind this door, so it stays blue when the door is not on him, and will become completely red when the door passes the character : EDIT : with this code, the black door hides the red and blue rectangles : (And if i add each of my layers at a different depth, and only use GL_LESS, same thing) blue.position = ccp( size.width*0.5 , size.height/2 ); red.position = ccp( size.width*0.46 , size.height/2 ); black.position = ccp( size.width*0.1 , size.height/2 ); glEnable(GL_DEPTH_TEST); [batch addChild:red z:0]; [batch addChild:black z:2]; glDepthFunc(GL_GREATER); [batch addChild:blue z:1]; glDepthFunc(GL_LESS); id action1 = [CCMoveTo actionWithDuration:3 position:ccp(size.width,size.height/2)]; [black runAction: [CCSequence actions:action1, nil]];

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  • Does anybody know of any resources to achieve this particular "2.5D" isometric engine effect?

    - by Craig Whitley
    I understand this is a little vague, but I was hoping somebody might be able to describe a high-level workflow or link to a resource to be able to achieve a specific isometric "2.5D" tile engine effect. I fell in love with http://www.youtube.com/watch?v=-Q6ISVaM5Ww this engine. Especially with the lighting and the shaders! He has a brief description of how he achieved what he did, but I could really use a brief flow of where you would start, what you would read up on and learn and the logical order to implement these things. A few specific questions: 1) Is there a heightmap on the ground texture that lets the light reflect brighter on certain parts of it? 2) "..using a special material which calculates the world-space normal vectors of every pixel.." - is this some "magic" special material he has created himself, or can you hazard a guess at what he means? 3) with relation to the above quote - what does he mean by 'world-space normal vectors of every pixel'? 4) I'm guessing I'm being a little bit optimistic when I ask if there's any 'all-in-one' tutorial out there? :)

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  • Why does Mass Effect 1 run so slow on my machine if I have an XFX NVidia 9400GT video card? [closed]

    - by Papuccino1
    I so sick and tired of having my components pass the minimum requirements of a game and then I get 15 FPS on the game on everything low. Should't PC developers say 'use at least this video card for a smooth 30 FPS'? Here are my specs: Windows 7 2GB DDR2 RAM XFX Nvidia 9400gt Intel Pentium D Dual Core 2.8ghz I should be at LEAST getting 30 FPS on everything low right? Please tell me what I can do to make games run as they should, or is my video card not good for these games? Here are the recommended requirements from the official site: Recommended System Requirements for Mass Effect on the PC Operating System: Windows XP or Vista Processor: 2.6+GHZ Intel or 2.4+GHZ AMD Memory: 2 Gigabyte Ram Video Card: NVIDIA GeForce 7900 GTX or higher. ATI X1800 XL series or higher Hard Drive Space: 12 Gigabytes Sound Card: DirectX 9.0c compatible sound card and drivers – 5.1 sound card recommended My videocard is 9400GT, how is that worse than a 7900GTX? :S Edit 2: I should note, that I get poor frames when running the game in absolute BOTTOM specs. lowest resolution, no particles, etc. etc. Absolute ZERO and getting poor framerates.

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  • How to mass insert/update in linq to sql?

    - by chobo2
    Hi How can I do these 2 scenarios. Currently I am doing something like this public class Repository { private LinqtoSqlContext dbcontext = new LinqtoSqlContext(); public void Update() { // find record // update record // save record ( dbcontext.submitChanges() } public void Insert() { // make a database table object ( ie ProductTable t = new ProductTable() { productname ="something"} // insert record ( dbcontext.ProductTable.insertOnSubmit()) // dbcontext.submitChanges(); } } So now I am trying to load an XML file what has tons of records. First I validate the records one at a time. I then want to insert them into the database but instead of doing submitChanges() after each record I want to do a mass submit at the end. So I have something like this public class Repository { private LinqtoSqlContext dbcontext = new LinqtoSqlContext(); public void Update() { // find record // update record } public void Insert() { // make a database table object ( ie ProductTable t = new ProductTable() { productname ="something"} // insert record ( dbcontext.ProductTable.insertOnSubmit()) } public void SaveToDb() { dbcontext.submitChanges(); } } Then in my service layer I would do like for(int i = 0; i < 100; i++) { validate(); if(valid == true) { update(); insert() } } SaveToDb(); So pretend my for loop is has a count for all the record found in the xml file. I first validate it. If valid then I have to update a table before I insert the record. I then insert the record. After that I want to save everything in one go. I am not sure if I can do a mass save when updating of if that has to be after every time or what. But I thought it would work for sure for the insert one. Nothing seems to crash and I am not sure how to check if the records are being added to the dbcontext.

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  • How can I remove all drivers and other files related to a USB Mass Storage device?

    - by Bob
    I have a flash drive here that does not work on one OS on computer - let's call it the desktop Windows 7. It works fine on another computer - laptop Windows 7. It also works fine on Windows 8 on the same desktop computer. Other flash drives work fine under desktop Windows 7. So not a hardware issue, not a generic USB Mass Storage driver issue. It's something specific to this drive. On desktop Windows 7, I can connect the drive but no volume comes up under Windows Explorer. Ditto for Disk Management. With diskpart, loading hangs until I unplug the drive, if I replug it and try list disk it hangs again. If I unplug the drive at this point, list disk prints out all attached drives - including the just removed flash drive. The drive consistently appears under Device Manager, but uninstalling the drivers, restarting and reinstalling the drivers (by inserting the drive) only works for the first insertion. After that it fails again. I get the feeling that the driver files are not actually removed, and are corrupted, meaning every reinstall it's the same corrupted drivers being installed. Is there any way to remove these drivers completely? Or perhaps some other setting Windows 7 retains? Formatting the drive through another computer/OS does not help. I've also tried a complete wipe and rebuild of the MBR and single partition. The allocation unit size makes no difference; neither does a NTFS format. This is a relatively small matter, and I would not like to reinstall the entire OS!

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  • Memory is full with vertex buffer

    - by Christian Frantz
    I'm having a pretty strange problem that I didn't think I'd run into. I was able to store a 50x50 grid in one vertex buffer finally, in hopes of better performance. Before I had each cube have an individual vertex buffer and with 4 50x50 grids, this slowed down my game tremendously. But it still ran. With 4 50x50 grids with my new code, that's only 4 vertex buffers. With the 4 vertex buffers, I get a memory error. When I load the game with 1 grid, it takes forever to load and with my previous version, it started up right away. So I don't know if I'm storing chunks wrong or what but it stumped me -.- for (int x = 0; x < 50; x++) { for (int z = 0; z < 50; z++) { for (int y = 0; y <= map[x, z]; y++) { SetUpVertices(); SetUpIndices(); cubes.Add(new Cube(device, new Vector3(x, map[x, z] - y, z), grass)); } } } vertexBuffer = new VertexBuffer(device, typeof(VertexPositionTexture), vertices.Count(), BufferUsage.WriteOnly); vertexBuffer.SetData<VertexPositionTexture>(vertices.ToArray()); indexBuffer = new IndexBuffer(device, typeof(short), indices.Count(), BufferUsage.WriteOnly); indexBuffer.SetData(indices.ToArray()); Thats how theyre stored. The array I'm reading from is a byte array which defines the coordinates of my map. Now with my old version, I used the same loading from an array so that hasn't changed. The only difference is the one vertex buffer instead of 2500 for a 50x50 grid. cubes is just a normal list that holds all my cubes for the vertex buffer. Another thing that just came to mind would be my draw calls. If I'm setting an effect for each cube in my cube list, that's probably going to take a lot of memory. How can I avoid doing this? I need the foreach method to set my cubes to the right position foreach (Cube block in cube.cubes) { effect.VertexColorEnabled = false; effect.TextureEnabled = true; Matrix center = Matrix.CreateTranslation(new Vector3(-0.5f, -0.5f, -0.5f)); Matrix scale = Matrix.CreateScale(1f); Matrix translate = Matrix.CreateTranslation(block.cubePosition); effect.World = center * scale * translate; effect.View = cam.view; effect.Projection = cam.proj; effect.FogEnabled = false; effect.FogColor = Color.CornflowerBlue.ToVector3(); effect.FogStart = 1.0f; effect.FogEnd = 50.0f; cube.Draw(effect); noc++; }

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  • How to apply effects that occur (or change) over time to characters in a game?

    - by Joshua Harris
    So assume that I have a system that applies Effects to Characters like so: public class Character { private Collection<Effect> _effects; public void AddEffect (Effect e) { e.ApplyTo(this); _effects.Add(e); } public void RemoveEffect (Effect e) { e.RemoveFrom(this); _effects.Remove(e); } } public interface Effect { public void ApplyTo (Character character); public void RemoveFrom (Character character); } Example Effect: Armor Buff for 5 seconds. void someFunction() { // Do Stuff ... Timer armorTimer = new Timer(5 seconds); ArmorBuff armorbuff = new ArmorBuff(); character.AddEffect(armorBuff); armorTimer.Start(); // Do more stuff ... } // Some where else in code public void ArmorTimer_Complete() { character.RemoveEffect(armorBuff); } public class ArmorBuff implements Effect { public void applyTo(Character character) { character.changeArmor(20); } public void removeFrom(Character character) { character.changeArmor(-20); } } Ok, so this example would buff the Characters armor for 5 seconds. Easy to get working. But what about effects that change over the duration of the effect being applied. Two examples come to mind: Damage Over Time: 200 damage every second for 3 seconds. I could mimic this by applying an Effect that lasts for 1 second and has a counter set to 3, then when it is removed it could deal 200 damage, clone itself, decrement the counter of the clone, and apply the clone to the character. If it repeats this until the counter is 0, then you got a damage over time ability. I'm not a huge fan of this approach, but it does describe the behavior exactly. Degenerating Speed Boost: Gain a speed boost that degrades over 3 seconds until you return to your normal speed. This is a bit harder. I can basically do the same thing as above except having timers set to some portion of a second, such that they occur fast enough to give the appearance of degenerating smoothly over time (even though they are really just stepping down incrementally). I feel like you could get away with only 12 steps over a second (maybe less, I would have to test it and see), but this doesn't seem very elegant to me. The only other way to implement this effect would be to change the system so that the Character checks the _effects collection for effects that alter any of the properties any time that they are being used. I could handle this in functions like getCurrentSpeed() and getCurrentArmor(), but you can imagine how much of a hassle it would be to have that kind of overhead every time you want to do a calculation with movement speed (which would be every time you move your character). Is there a better way to deal with these kinds of effects or events?

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  • How to create a hover effect in a newsletter?

    - by Moak
    I'm creating a newsletter, and i want to have panels that change background-color on mouse over. Seeing as the newsletter wont have a head, I am defining all styles inline. I'm pretty sure most popular mail clients will block JS. So I was wondering if I can define a hover effect in the style attribute. Or is there any other solution to achieve this effect? Peace

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  • Avoid being blocked by web mail companies for mass/bulk emailing ?

    - by Johannes
    Our company is sending out a lot of emails per day and planning to send even more in future. (thousands) Also there are mass mailouts as well in the ten thousands every now and then. Anybody has experience with hotmail, yahoo (web.de, gmx.net) and similar webmail companies blocking your emails because "too many from the same source in a period of time" have been sent to them? What can be done about it? Spreading email mailouts over a whole day/night? At what rate? (we are talking about legal emailing just to make sure...)

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  • How do I avoid nesting forms when offering inline editing of lists with checkboxes for mass updates.

    - by adam
    A lot of sites offer the ability to edit lists of items inline as well as allowing multiple items to be selected via checkboxes and have an action performed all at once e.g. delete, mark as spam etc. But how do you implement this without violating html rules. I need one form for the checkboxes with individual submit_tags for the mass actions. But after a user clicks on an item in the list, another form via Ajax will be inserted within the checkbox form. How do I avoid doing this? I'm using rails and jQuery.

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  • Toorcon 15 (2013)

    - by danx
    The Toorcon gang (senior staff): h1kari (founder), nfiltr8, and Geo Introduction to Toorcon 15 (2013) A Tale of One Software Bypass of MS Windows 8 Secure Boot Breaching SSL, One Byte at a Time Running at 99%: Surviving an Application DoS Security Response in the Age of Mass Customized Attacks x86 Rewriting: Defeating RoP and other Shinanighans Clowntown Express: interesting bugs and running a bug bounty program Active Fingerprinting of Encrypted VPNs Making Attacks Go Backwards Mask Your Checksums—The Gorry Details Adventures with weird machines thirty years after "Reflections on Trusting Trust" Introduction to Toorcon 15 (2013) Toorcon 15 is the 15th annual security conference held in San Diego. I've attended about a third of them and blogged about previous conferences I attended here starting in 2003. As always, I've only summarized the talks I attended and interested me enough to write about them. Be aware that I may have misrepresented the speaker's remarks and that they are not my remarks or opinion, or those of my employer, so don't quote me or them. Those seeking further details may contact the speakers directly or use The Google. For some talks, I have a URL for further information. A Tale of One Software Bypass of MS Windows 8 Secure Boot Andrew Furtak and Oleksandr Bazhaniuk Yuri Bulygin, Oleksandr ("Alex") Bazhaniuk, and (not present) Andrew Furtak Yuri and Alex talked about UEFI and Bootkits and bypassing MS Windows 8 Secure Boot, with vendor recommendations. They previously gave this talk at the BlackHat 2013 conference. MS Windows 8 Secure Boot Overview UEFI (Unified Extensible Firmware Interface) is interface between hardware and OS. UEFI is processor and architecture independent. Malware can replace bootloader (bootx64.efi, bootmgfw.efi). Once replaced can modify kernel. Trivial to replace bootloader. Today many legacy bootkits—UEFI replaces them most of them. MS Windows 8 Secure Boot verifies everything you load, either through signatures or hashes. UEFI firmware relies on secure update (with signed update). You would think Secure Boot would rely on ROM (such as used for phones0, but you can't do that for PCs—PCs use writable memory with signatures DXE core verifies the UEFI boat loader(s) OS Loader (winload.efi, winresume.efi) verifies the OS kernel A chain of trust is established with a root key (Platform Key, PK), which is a cert belonging to the platform vendor. Key Exchange Keys (KEKs) verify an "authorized" database (db), and "forbidden" database (dbx). X.509 certs with SHA-1/SHA-256 hashes. Keys are stored in non-volatile (NV) flash-based NVRAM. Boot Services (BS) allow adding/deleting keys (can't be accessed once OS starts—which uses Run-Time (RT)). Root cert uses RSA-2048 public keys and PKCS#7 format signatures. SecureBoot — enable disable image signature checks SetupMode — update keys, self-signed keys, and secure boot variables CustomMode — allows updating keys Secure Boot policy settings are: always execute, never execute, allow execute on security violation, defer execute on security violation, deny execute on security violation, query user on security violation Attacking MS Windows 8 Secure Boot Secure Boot does NOT protect from physical access. Can disable from console. Each BIOS vendor implements Secure Boot differently. There are several platform and BIOS vendors. It becomes a "zoo" of implementations—which can be taken advantage of. Secure Boot is secure only when all vendors implement it correctly. Allow only UEFI firmware signed updates protect UEFI firmware from direct modification in flash memory protect FW update components program SPI controller securely protect secure boot policy settings in nvram protect runtime api disable compatibility support module which allows unsigned legacy Can corrupt the Platform Key (PK) EFI root certificate variable in SPI flash. If PK is not found, FW enters setup mode wich secure boot turned off. Can also exploit TPM in a similar manner. One is not supposed to be able to directly modify the PK in SPI flash from the OS though. But they found a bug that they can exploit from User Mode (undisclosed) and demoed the exploit. It loaded and ran their own bootkit. The exploit requires a reboot. Multiple vendors are vulnerable. They will disclose this exploit to vendors in the future. Recommendations: allow only signed updates protect UEFI fw in ROM protect EFI variable store in ROM Breaching SSL, One Byte at a Time Yoel Gluck and Angelo Prado Angelo Prado and Yoel Gluck, Salesforce.com CRIME is software that performs a "compression oracle attack." This is possible because the SSL protocol doesn't hide length, and because SSL compresses the header. CRIME requests with every possible character and measures the ciphertext length. Look for the plaintext which compresses the most and looks for the cookie one byte-at-a-time. SSL Compression uses LZ77 to reduce redundancy. Huffman coding replaces common byte sequences with shorter codes. US CERT thinks the SSL compression problem is fixed, but it isn't. They convinced CERT that it wasn't fixed and they issued a CVE. BREACH, breachattrack.com BREACH exploits the SSL response body (Accept-Encoding response, Content-Encoding). It takes advantage of the fact that the response is not compressed. BREACH uses gzip and needs fairly "stable" pages that are static for ~30 seconds. It needs attacker-supplied content (say from a web form or added to a URL parameter). BREACH listens to a session's requests and responses, then inserts extra requests and responses. Eventually, BREACH guesses a session's secret key. Can use compression to guess contents one byte at-a-time. For example, "Supersecret SupersecreX" (a wrong guess) compresses 10 bytes, and "Supersecret Supersecret" (a correct guess) compresses 11 bytes, so it can find each character by guessing every character. To start the guess, BREACH needs at least three known initial characters in the response sequence. Compression length then "leaks" information. Some roadblocks include no winners (all guesses wrong) or too many winners (multiple possibilities that compress the same). The solutions include: lookahead (guess 2 or 3 characters at-a-time instead of 1 character). Expensive rollback to last known conflict check compression ratio can brute-force first 3 "bootstrap" characters, if needed (expensive) block ciphers hide exact plain text length. Solution is to align response in advance to block size Mitigations length: use variable padding secrets: dynamic CSRF tokens per request secret: change over time separate secret to input-less servlets Future work eiter understand DEFLATE/GZIP HTTPS extensions Running at 99%: Surviving an Application DoS Ryan Huber Ryan Huber, Risk I/O Ryan first discussed various ways to do a denial of service (DoS) attack against web services. One usual method is to find a slow web page and do several wgets. Or download large files. Apache is not well suited at handling a large number of connections, but one can put something in front of it Can use Apache alternatives, such as nginx How to identify malicious hosts short, sudden web requests user-agent is obvious (curl, python) same url requested repeatedly no web page referer (not normal) hidden links. hide a link and see if a bot gets it restricted access if not your geo IP (unless the website is global) missing common headers in request regular timing first seen IP at beginning of attack count requests per hosts (usually a very large number) Use of captcha can mitigate attacks, but you'll lose a lot of genuine users. Bouncer, goo.gl/c2vyEc and www.github.com/rawdigits/Bouncer Bouncer is software written by Ryan in netflow. Bouncer has a small, unobtrusive footprint and detects DoS attempts. It closes blacklisted sockets immediately (not nice about it, no proper close connection). Aggregator collects requests and controls your web proxies. Need NTP on the front end web servers for clean data for use by bouncer. Bouncer is also useful for a popularity storm ("Slashdotting") and scraper storms. Future features: gzip collection data, documentation, consumer library, multitask, logging destroyed connections. Takeaways: DoS mitigation is easier with a complete picture Bouncer designed to make it easier to detect and defend DoS—not a complete cure Security Response in the Age of Mass Customized Attacks Peleus Uhley and Karthik Raman Peleus Uhley and Karthik Raman, Adobe ASSET, blogs.adobe.com/asset/ Peleus and Karthik talked about response to mass-customized exploits. Attackers behave much like a business. "Mass customization" refers to concept discussed in the book Future Perfect by Stan Davis of Harvard Business School. Mass customization is differentiating a product for an individual customer, but at a mass production price. For example, the same individual with a debit card receives basically the same customized ATM experience around the world. Or designing your own PC from commodity parts. Exploit kits are another example of mass customization. The kits support multiple browsers and plugins, allows new modules. Exploit kits are cheap and customizable. Organized gangs use exploit kits. A group at Berkeley looked at 77,000 malicious websites (Grier et al., "Manufacturing Compromise: The Emergence of Exploit-as-a-Service", 2012). They found 10,000 distinct binaries among them, but derived from only a dozen or so exploit kits. Characteristics of Mass Malware: potent, resilient, relatively low cost Technical characteristics: multiple OS, multipe payloads, multiple scenarios, multiple languages, obfuscation Response time for 0-day exploits has gone down from ~40 days 5 years ago to about ~10 days now. So the drive with malware is towards mass customized exploits, to avoid detection There's plenty of evicence that exploit development has Project Manager bureaucracy. They infer from the malware edicts to: support all versions of reader support all versions of windows support all versions of flash support all browsers write large complex, difficult to main code (8750 lines of JavaScript for example Exploits have "loose coupling" of multipe versions of software (adobe), OS, and browser. This allows specific attacks against specific versions of multiple pieces of software. Also allows exploits of more obscure software/OS/browsers and obscure versions. Gave examples of exploits that exploited 2, 3, 6, or 14 separate bugs. However, these complete exploits are more likely to be buggy or fragile in themselves and easier to defeat. Future research includes normalizing malware and Javascript. Conclusion: The coming trend is that mass-malware with mass zero-day attacks will result in mass customization of attacks. x86 Rewriting: Defeating RoP and other Shinanighans Richard Wartell Richard Wartell The attack vector we are addressing here is: First some malware causes a buffer overflow. The malware has no program access, but input access and buffer overflow code onto stack Later the stack became non-executable. The workaround malware used was to write a bogus return address to the stack jumping to malware Later came ASLR (Address Space Layout Randomization) to randomize memory layout and make addresses non-deterministic. The workaround malware used was to jump t existing code segments in the program that can be used in bad ways "RoP" is Return-oriented Programming attacks. RoP attacks use your own code and write return address on stack to (existing) expoitable code found in program ("gadgets"). Pinkie Pie was paid $60K last year for a RoP attack. One solution is using anti-RoP compilers that compile source code with NO return instructions. ASLR does not randomize address space, just "gadgets". IPR/ILR ("Instruction Location Randomization") randomizes each instruction with a virtual machine. Richard's goal was to randomize a binary with no source code access. He created "STIR" (Self-Transofrming Instruction Relocation). STIR disassembles binary and operates on "basic blocks" of code. The STIR disassembler is conservative in what to disassemble. Each basic block is moved to a random location in memory. Next, STIR writes new code sections with copies of "basic blocks" of code in randomized locations. The old code is copied and rewritten with jumps to new code. the original code sections in the file is marked non-executible. STIR has better entropy than ASLR in location of code. Makes brute force attacks much harder. STIR runs on MS Windows (PEM) and Linux (ELF). It eliminated 99.96% or more "gadgets" (i.e., moved the address). Overhead usually 5-10% on MS Windows, about 1.5-4% on Linux (but some code actually runs faster!). The unique thing about STIR is it requires no source access and the modified binary fully works! Current work is to rewrite code to enforce security policies. For example, don't create a *.{exe,msi,bat} file. Or don't connect to the network after reading from the disk. Clowntown Express: interesting bugs and running a bug bounty program Collin Greene Collin Greene, Facebook Collin talked about Facebook's bug bounty program. Background at FB: FB has good security frameworks, such as security teams, external audits, and cc'ing on diffs. But there's lots of "deep, dark, forgotten" parts of legacy FB code. Collin gave several examples of bountied bugs. Some bounty submissions were on software purchased from a third-party (but bounty claimers don't know and don't care). We use security questions, as does everyone else, but they are basically insecure (often easily discoverable). Collin didn't expect many bugs from the bounty program, but they ended getting 20+ good bugs in first 24 hours and good submissions continue to come in. Bug bounties bring people in with different perspectives, and are paid only for success. Bug bounty is a better use of a fixed amount of time and money versus just code review or static code analysis. The Bounty program started July 2011 and paid out $1.5 million to date. 14% of the submissions have been high priority problems that needed to be fixed immediately. The best bugs come from a small % of submitters (as with everything else)—the top paid submitters are paid 6 figures a year. Spammers like to backstab competitors. The youngest sumitter was 13. Some submitters have been hired. Bug bounties also allows to see bugs that were missed by tools or reviews, allowing improvement in the process. Bug bounties might not work for traditional software companies where the product has release cycle or is not on Internet. Active Fingerprinting of Encrypted VPNs Anna Shubina Anna Shubina, Dartmouth Institute for Security, Technology, and Society (I missed the start of her talk because another track went overtime. But I have the DVD of the talk, so I'll expand later) IPsec leaves fingerprints. Using netcat, one can easily visually distinguish various crypto chaining modes just from packet timing on a chart (example, DES-CBC versus AES-CBC) One can tell a lot about VPNs just from ping roundtrips (such as what router is used) Delayed packets are not informative about a network, especially if far away from the network More needed to explore about how TCP works in real life with respect to timing Making Attacks Go Backwards Fuzzynop FuzzyNop, Mandiant This talk is not about threat attribution (finding who), product solutions, politics, or sales pitches. But who are making these malware threats? It's not a single person or group—they have diverse skill levels. There's a lot of fat-fingered fumblers out there. Always look for low-hanging fruit first: "hiding" malware in the temp, recycle, or root directories creation of unnamed scheduled tasks obvious names of files and syscalls ("ClearEventLog") uncleared event logs. Clearing event log in itself, and time of clearing, is a red flag and good first clue to look for on a suspect system Reverse engineering is hard. Disassembler use takes practice and skill. A popular tool is IDA Pro, but it takes multiple interactive iterations to get a clean disassembly. Key loggers are used a lot in targeted attacks. They are typically custom code or built in a backdoor. A big tip-off is that non-printable characters need to be printed out (such as "[Ctrl]" "[RightShift]") or time stamp printf strings. Look for these in files. Presence is not proof they are used. Absence is not proof they are not used. Java exploits. Can parse jar file with idxparser.py and decomile Java file. Java typially used to target tech companies. Backdoors are the main persistence mechanism (provided externally) for malware. Also malware typically needs command and control. Application of Artificial Intelligence in Ad-Hoc Static Code Analysis John Ashaman John Ashaman, Security Innovation Initially John tried to analyze open source files with open source static analysis tools, but these showed thousands of false positives. Also tried using grep, but tis fails to find anything even mildly complex. So next John decided to write his own tool. His approach was to first generate a call graph then analyze the graph. However, the problem is that making a call graph is really hard. For example, one problem is "evil" coding techniques, such as passing function pointer. First the tool generated an Abstract Syntax Tree (AST) with the nodes created from method declarations and edges created from method use. Then the tool generated a control flow graph with the goal to find a path through the AST (a maze) from source to sink. The algorithm is to look at adjacent nodes to see if any are "scary" (a vulnerability), using heuristics for search order. The tool, called "Scat" (Static Code Analysis Tool), currently looks for C# vulnerabilities and some simple PHP. Later, he plans to add more PHP, then JSP and Java. For more information see his posts in Security Innovation blog and NRefactory on GitHub. Mask Your Checksums—The Gorry Details Eric (XlogicX) Davisson Eric (XlogicX) Davisson Sometimes in emailing or posting TCP/IP packets to analyze problems, you may want to mask the IP address. But to do this correctly, you need to mask the checksum too, or you'll leak information about the IP. Problem reports found in stackoverflow.com, sans.org, and pastebin.org are usually not masked, but a few companies do care. If only the IP is masked, the IP may be guessed from checksum (that is, it leaks data). Other parts of packet may leak more data about the IP. TCP and IP checksums both refer to the same data, so can get more bits of information out of using both checksums than just using one checksum. Also, one can usually determine the OS from the TTL field and ports in a packet header. If we get hundreds of possible results (16x each masked nibble that is unknown), one can do other things to narrow the results, such as look at packet contents for domain or geo information. With hundreds of results, can import as CSV format into a spreadsheet. Can corelate with geo data and see where each possibility is located. Eric then demoed a real email report with a masked IP packet attached. Was able to find the exact IP address, given the geo and university of the sender. Point is if you're going to mask a packet, do it right. Eric wouldn't usually bother, but do it correctly if at all, to not create a false impression of security. Adventures with weird machines thirty years after "Reflections on Trusting Trust" Sergey Bratus Sergey Bratus, Dartmouth College (and Julian Bangert and Rebecca Shapiro, not present) "Reflections on Trusting Trust" refers to Ken Thompson's classic 1984 paper. "You can't trust code that you did not totally create yourself." There's invisible links in the chain-of-trust, such as "well-installed microcode bugs" or in the compiler, and other planted bugs. Thompson showed how a compiler can introduce and propagate bugs in unmodified source. But suppose if there's no bugs and you trust the author, can you trust the code? Hell No! There's too many factors—it's Babylonian in nature. Why not? Well, Input is not well-defined/recognized (code's assumptions about "checked" input will be violated (bug/vunerabiliy). For example, HTML is recursive, but Regex checking is not recursive. Input well-formed but so complex there's no telling what it does For example, ELF file parsing is complex and has multiple ways of parsing. Input is seen differently by different pieces of program or toolchain Any Input is a program input executes on input handlers (drives state changes & transitions) only a well-defined execution model can be trusted (regex/DFA, PDA, CFG) Input handler either is a "recognizer" for the inputs as a well-defined language (see langsec.org) or it's a "virtual machine" for inputs to drive into pwn-age ELF ABI (UNIX/Linux executible file format) case study. Problems can arise from these steps (without planting bugs): compiler linker loader ld.so/rtld relocator DWARF (debugger info) exceptions The problem is you can't really automatically analyze code (it's the "halting problem" and undecidable). Only solution is to freeze code and sign it. But you can't freeze everything! Can't freeze ASLR or loading—must have tables and metadata. Any sufficiently complex input data is the same as VM byte code Example, ELF relocation entries + dynamic symbols == a Turing Complete Machine (TM). @bxsays created a Turing machine in Linux from relocation data (not code) in an ELF file. For more information, see Rebecca "bx" Shapiro's presentation from last year's Toorcon, "Programming Weird Machines with ELF Metadata" @bxsays did same thing with Mach-O bytecode Or a DWARF exception handling data .eh_frame + glibc == Turning Machine X86 MMU (IDT, GDT, TSS): used address translation to create a Turning Machine. Page handler reads and writes (on page fault) memory. Uses a page table, which can be used as Turning Machine byte code. Example on Github using this TM that will fly a glider across the screen Next Sergey talked about "Parser Differentials". That having one input format, but two parsers, will create confusion and opportunity for exploitation. For example, CSRs are parsed during creation by cert requestor and again by another parser at the CA. Another example is ELF—several parsers in OS tool chain, which are all different. Can have two different Program Headers (PHDRs) because ld.so parses multiple PHDRs. The second PHDR can completely transform the executable. This is described in paper in the first issue of International Journal of PoC. Conclusions trusting computers not only about bugs! Bugs are part of a problem, but no by far all of it complex data formats means bugs no "chain of trust" in Babylon! (that is, with parser differentials) we need to squeeze complexity out of data until data stops being "code equivalent" Further information See and langsec.org. USENIX WOOT 2013 (Workshop on Offensive Technologies) for "weird machines" papers and videos.

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