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  • Checking for a session variable... returns (Object reference not set to an instance of an object.)

    - by Chocol8
    In the Session_Start i have Sub Session_Start(ByVal sender As Object, ByVal e As EventArgs) Session("login") = False End Sub and in a custom .aspx page i included the following... Public ReadOnly Property GetLoginState() As Boolean Get If Current.Session("login") Is Nothing Then Current.Session("login") = False End If Return Current.Session("login") End Get End Property Why i am getting error the error Object reference not set to an instance of an object. at line If Current.Session("login") Is Nothing Then while checking for the login state as follows? If GetLogin = False Then 'Do something End if I mean i have already created the instance on the Session_Start... Haven't i? What am i doing wrong here?

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  • What does Heroku mean by app[web.1]?

    - by Colonel Panic
    What does Heroku mean by app[web.1] and by <main>:48? I have a crash that happens only on Heroku and not on my computer, I'm trying to identify the precise line causing the crash. These are the logs heroku[web.1]:?[0m Starting process with command `bundle exec rackup config.ru -s thin -p 40103` app[web.1]:?[0m <main>:48:in `method_missing': wrong number of arguments (1 for 2) (ArgumentError) app[web.1]:?[0m from /app/vendor/bundle/ruby/1.9.1/gems/rack-1.4.1/lib/rack/server.rb:265:in `start' ... heroku[web.1]:?[0m Process exited with status 1 heroku[web.1]:?[0m State changed from starting to crashed

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  • DAQ Triggers in Matlab

    - by RidePlanet
    I'm writing a program that detects the speed of a object by hall effect sensors that are run into MATLAB through a DAQ (MCC USB-1408FS) The problem that has arisen is that I'm using a non-stop scan technique to detect the state of one of 3 sensors. Unfortunately this means that unless the object is rotating past each sensor at the exact rate the program runs, I will see an instantaneous speed (done by comparing the time between two sensors) of zero. I need the sensors to signal the program to count when they are hit, instead of constantly scanning for the signal. How can this be done?

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  • where to place browser event (resize/scroll) detection call

    - by karl
    I'm trying to alert a message when the browser is resized or scrolled. I'm detecting the 2 events in the body <body onResize="doDisp();" onScroll="doDisp();" > where doDisp is this inside the <script> tag <script type="text/javascript"> function doDisp(){ alert("browser changing state"); } </script> but isn't it bad practice to have javascript in the body tag? Is there a cross-browser way to keep all the javascript inside the <script> tags?

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  • How to change text via jQuery?

    - by Will Merydith
    I am trying to change the "show more" text depending on the state. This isn't working: <div id="description"> text goes here </div> <div id="more-less-container"> <a href="#" id="more-less">expand / collapse</a> </div> <script> var open = false; $('#more-less').click(function() { if (open) { $('#description').animate({height:'10em'}); $('#more-less').innerHTML ='show less'; } else { $('#description').animate({height:'100%'}); $('#more-less').innerHTML ='show more'; } open = !open; }); </script>

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  • Oracle checking existence before deletion in a trigger

    I have analyzed a hibernate generated oracle database and discovered that a delete of a row from a single table will spawn the firing of 1200+ triggers in order to delete the related rows in child tables. The triggers are all auto-generated the same - an automatic delete of a child row without checking for existence first. As it is impossible to predict which child tables will actually have related rows, I think a viable solution to preventing the firing of the cascaded delete down a deeply branched completely empty limb, would be to check for the existence of a related row before attempting to delete. In other dbms', I could simply state " if exists....." before deleting. Is there a comparable way to do this in oracle?

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  • I have submitted app to app store and app status came like 'Metadata Rejected' and following review status. I do not have login page

    - by user3717465
    We began the review of your app but are not able to continue because we need a demo account to fully access your app features. Please provide demo account details in the Review Notes section of the Version Information for your app. Please ensure that the information you provide includes any data necessary to demonstrate the functionality of your app features. You can provide demo account information, including passwords, in the Review Notes section of your iTunes Connect App Information. While your iTunes Connect Application State shows as Metadata Rejected, we don't require a new binary to correct this issue. Please visit iTunes Connect, Manage Your Applications. Select your app, then click View Details of the desired version. Click the Edit button next to Version Information to edit the Review Notes for your app, then click "Save". how to correct the meta data. because i do not have login account.

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  • What Design Pattern To Replace 'CurrentStep' Variable

    - by Rob P.
    Tried to search but didn't know how to phrase it. I've got some code that is essentially... Private CurMajorStep as Integer = 0 Private CurMinorStep as Integer = 0 Public Sub PerformNextStep() Select Case iMajorStep Case 0 ThingOne() Case 1 ThingTwo() Case 2 ThingThree() Case 3 ThingFour() Case 4 AnythingElse() Case 5 Finish() End Select End Sub And then, in some of those, the CurMinorStep keeps track of the current state of that particular 'step'. I hope that all makes sense. The code is messy and I know it's going to be problematic to maintain. Can someone point me to a clean OO pattern to handle this?

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  • variable scope in statement blocks

    - by fearofawhackplanet
    for (int i = 0; i < 10; i++) { Foo(); } int i = 10; // error, 'i' already exists ---------------------------------------- for (int i = 0; i < 10; i++) { Foo(); } i = 10; // error, 'i' doesn't exist By my understanding of scope, the first example should be fine. The fact neither of them are allowed seems even more odd. Surely 'i' is either in scope or not. Is there something non-obvious about scope I don't understand which means the compiler genuinely can't resolve this? Or is just a case of nanny-state compilerism?

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  • Considerations when porting a MS VC++ program (single machine) to a rocks cluster

    - by Mel
    I am trying to port a MS VC++ program to run on a rocks cluster! I am not very good with linux but I am eager to learn and I imagine porting it wouldn't be an impossible task for me. However, I do not understand how to take advantage of the cluster nodes. because it seems that the code execute only runs on the front end server (obviously). I have read a little about MPI and its seems like I should use MPI to comminicate between nodes. The program is currently written such that I have a main thread that synchronizes all worker threads. The main thread also recieves commands to manipulate the simulation or query its state. If the simulation is properly setup, communication between executing threads can be significantly minimized. What I don't understand is how do I start the process on the compute nodes and how do I handle failures in nodes? And maybe there should be other things I should also consider when porting my program to run in a cluster?

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  • SQL 2000 Multiple IF Statements

    - by Spidermain50
    I get a error when I try to use multiple IF statements. This is the error... "Msg 156, Level 15, State 1, Procedure fnTNAccidentIndicator, Line 81 Incorrect syntax near the keyword 'END'." This is the structure of my code... USE SS_TNRecords_Accident SET ANSI_NULLS ON GO SET QUOTED_IDENTIFIER ON GO CREATE FUNCTION dbo.fnTNAccidentIndicator ( @inAccidentNumber nvarchar, @inIndicatorMode int ) RETURNS nvarchar AS BEGIN DECLARE @AlcoholInd nvarchar DECLARE @DrugInd nvarchar DECLARE @SpeedInd nvarchar DECLARE @ReturnValue nvarchar SET @AlcoholInd = '1' SET @DrugInd = '2' SET @SpeedInd = '3' SET @ReturnValue = 'N' IF (@inIndicatorMode = @AlcoholInd) BEGIN --select statment IF (@@ROWCOUNT > 0) BEGIN @ReturnValue = 'Y' END END IF (@inIndicatorMode = @DrugInd) BEGIN --select statment IF (@@ROWCOUNT > 0) BEGIN @ReturnValue = 'Y' END END IF (@inIndicatorMode = @SpeedInd) BEGIN --select statment IF (@@ROWCOUNT > 0) BEGIN @ReturnValue = 'Y' END END Return @ReturnValue END GO

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  • [Android] Returning to a ListView with a text filter

    - by sosiouxme
    I enabled text filtering on my ListView in the expected way; adding android:textFilterEnabled=”true” in resource definition and (as I'm using a SimpleCursorAdapter) setting a FilterQueryProvider that provides a filtered cursor like so: public Cursor runQuery(CharSequence constraint) { Cursor cur = mDba.fetchTrackers(mCurrentGroupId, constraint.toString()); startManagingCursor(cur); return cur; } My question is this: once the user selects a list item, goes off to another activity, and returns to this one, how can I control the state of the filter previously applied? What I'm seeing right now is that when I return to the activity, the cursor being used is the unfiltered one set on the filter at creation, but the filter text they typed is still shown (and typing keys causes the filter to be applied). What I'd like to do is either clear the filter, or keep the filtered cursor that the activity was left with.

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  • Help me vaildate these points regarding Ruby

    - by Bragaadeesh
    Hi, I have started learning Ruby for the past 2,3 weeks and I have come up with some findings on the language. Can someone please validate these points. Implemented in many other high level languages such as C, Java, .Net etc., Is slow for the obvious reason that it cannot beat any of the already known high level languages. Should never be compared with any other high level language. Not suitable for large applications. Completely open source and is in a budding state. Has a framework called Rails which claims that it would be good for Agile development Community out there is getting better day by day and finding help immediately should not be a problem as time goes by. Has significant changes between releases which many developers wont welcome right away. Running time cannot be comprehensively estimated since the language has several underlying implementation in several languages. Books are always outdated by the time when you finish them. Thanks.

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  • Preventing click event with jQuery drag and drop

    - by Sasha Yanovets
    I have an elements on page that are draggabe with jQuery. These elements have click event wich navigates to another page (ordinary links for example). What is the best way to prevent click from firing on dropping such element, while allowing clicking it in not drag and drop state? I have this problem with sortable elements, but think it is good to have solution for general drag and drop. I've solved the problem for myself. After that found that same solution exists for Scriptaculous, but maybe someone have a better way to achieve that.

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  • How do I display/compare a dynamic value of a mysql row in a if statement?

    - by Ralph The Mouf
    I have a checkboxes on my site that when unchecked, update their row in in the db as unchecked, and if checked,update their row in the db as checked. I am creating an ifstatement that will commence with its command if checked, and not if unchecked. I have echoed the variable and it is holding the proper value (checked or unchecked) but not sure if I am syntactically correct on displaying the state of the row in the db. This is what I am trying and will not work. I am new at php still and thank you very much for any help. if($auth->check_prof == 'checked'){// do the stuff in here}

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  • quickflip + slideshow animation

    - by user288231
    I have been trying to integrate quickflip and a slideshow animation. So everytime when the user hovers over the image, it would pause the animation and "flip to the other side". When the user hovers out, it would then replace its normal state. The problem is here is I do not know how to handle the quickflip code (http://jonraasch.com/blog/quickflip-2-jquery-plugin). I have looked at the sample code and tried to replace it, but at the end the animations would get messed up... Javascript: var interval = setInterval( "slideSwitch()", 3000 ); $('.quickFlip').quickFlip(); $('#slideshow').hover(function () { clearInterval(interval); }, function () { interval = setInterval("slideSwitch()", 3000); });

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  • Poll: What is stopping you from switching (from Java) to Scala ?

    - by Lukasz Lew
    What would make you to switch to Scala ? If you are negative on the switching to Scala, please state the reason as well (or upvote). As with all StackOverflow Poll type Q&As, please make certain your answer is NOT listed already before adding a new answer If it already exists, vote that one up so we see what the most popular answer is, rather than duplicating an existing entry. If you see a duplicate, vote it down. If you have interesting or additional information to add, use a comment or edit the original entry rather than creating a duplicate.

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  • ActionScript - One Button Limit (Exclusive Touch) For Mobile Devices?

    - by TheDarkIn1978
    two years ago, when i was developing an application for the iPhone, i used the following built-in system method on all of my buttons: [button setExclusiveTouch:YES]; essentially, if you had many buttons on screen, this method insured that the application wouldn't be permitted do crazy things when several button events firing at the same time. problematic: ButtonA and ButtonB are available. each button has a mouse up event which fire a specific reorganization/layout of the UI. if both button's events are fired at the same time, their events will likely conflict, causing a strange new layout, perhaps a runtime error. solution: application buttons cancel any current pending mouse up events when said button enters mouse down. private function mouseDownEventHandler(evt:MouseEvent):void { //if other buttons are currently in a mouse down state ready to fire //a mouse up event, cancel them all here. } of course it's simple to manually handle this if there are only a few buttons on stage, but managing buttons becomes more and more complicated / bug-prone if there are several / many buttons available. is there a convenience method available in AIR specifically for this functionality?

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  • C# - Silverlight - Custom control or UserControl ?

    - by cmaduro
    I need a button that is visually completely customizable, but has custom logic to publish events and manage it's visual state based on events it has registered for. When I say visually customizable, I mean I should be able to both create the button in xaml and set it's style by binding to the supplied style. Or I can create an instance of the button and set the style by passing a parameter to an alternate constructor. Or by calling a method on the button class to set the style. I do not plan on substituting the controls template, it should be a button. Can anyone point me to some code samples of this?

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  • Does Jquery UI Dialog Destroy event remove the html too?

    - by chobo2
    Hi I have a dialog that displays a form. When they save or close the dialog I call up the jquery dialog destroy method. However I am not clear if it removes the html div. From the description I would not think so Remove the dialog functionality completely. This will return the element back to its pre-init state. However when looking with firebug I can't see the html container so I am not sure if it gets removed or what. I am not sure if it is because I make the div for the dialog on the fly and use jquery to add it to the page.

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  • RVM 1.9.1 & nokogiri

    - by scaney
    Having trouble installing the nokogiri gem under rvm ruby 1.9.1. gem install nokogiri I'm getting ... /usr/include/libxml2... no libxml2 is missing. try 'port install libxml2' or 'yum install libxml2-devel' *** extconf.rb failed *** but i checked: sudo apt-get install libxml2 and i got: Reading state information... Done libxml2 is already the newest version. is this a root thing perhaps? RVM runs everything in userspace.

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  • Running lmgrd on ubuntu 14.04 LTS

    - by SumanBhatR
    I have installed Xilinx 14.7 in ubuntu 14.04 LTS machine(i386 - 64bit). But I am unable to run lmgrd (for starting the license server). When I googled this problem, I found that lsb-core package needs to be installed. But the package is having many dependencies, I want to know how to install lsb-core package with all the necessary dependencies. Thanks for the help On running sudo apt-get install lsb-core I got the following output Reading package lists... Done Building dependency tree Reading state information... Done Package lsb-core is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source E: Package 'lsb-core' has no installation candidate So I downloaded lsb-core package from http://packages.ubuntu.com/trusty/misc/lsb-core site and used "sudo dpkg -i ./lsb-core_4.1+Debian11ubuntu6_i386.deb" to install it By doing it, I got the following output Selecting previously unselected package lsb-core. (Reading database ... 163205 files and directories currently installed.) Preparing to unpack .../lsb-core_4.1+Debian11ubuntu6_i386.deb ... Unpacking lsb-core (4.1+Debian11ubuntu6) ... dpkg: dependency problems prevent configuration of lsb-core: lsb-core depends on libc6 ( 2.3.5). lsb-core depends on libz1. lsb-core depends on libncurses5. lsb-core depends on libpam0g. lsb-core depends on lsb-invalid-mta (= 4.1+Debian11ubuntu6) | mail-transport-agent. lsb-core depends on at. lsb-core depends on binutils. lsb-core depends on cron | cron-daemon. lsb-core depends on libc6-dev | libc-dev. lsb-core depends on locales. lsb-core depends on m4. lsb-core depends on mailx | mailutils. lsb-core depends on ncurses-term. lsb-core depends on pax. lsb-core depends on psmisc. lsb-core depends on alien (= 8.36). lsb-core depends on python3. lsb-core depends on lsb-security (= 4.1+Debian11ubuntu6). lsb-core depends on time. dpkg: error processing package lsb-core (--install): dependency problems - leaving unconfigured Processing triggers for man-db (2.6.7.1-1) ... Errors were encountered while processing: lsb-core So I want to know how to install lsb-core package with all the necessary dependencies in one go. Thanks for the help

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  • SQL SERVER – Fix : Error 3623 – An invalid floating point operation occurred

    - by pinaldave
    Going back in time, I always had a problem with mathematics. It was a great subject and I loved it a lot but I only mastered it after practices a lot. I learned that mathematics problems should be addressed systematically and being verbose is not a trick, I learned to solve any problem. Recently one of reader sent me an email with the title “Mathematics problem – please help!” and I was a bit scared. I was good at mathematics but not the best. When I opened the email I was relieved as it was Mathematics problem with SQL Server. My friend received following error while working with SQL Server. Msg 3623, Level 16, State 1, Line 1 An invalid floating point operation occurred. The reasons for the error is simply that invalid usage of the mathematical function is attempted. Let me give you a few examples of the same. SELECT SQRT(-5); SELECT ACOS(-3); SELECT LOG(-9); If you run any of the above functions they will give you an error related to invalid floating point. Honestly there is no workaround except passing the function appropriate values. SQRT of a negative number will give you result in real numbers which is not supported at this point of time as well LOG of a negative number is not possible (because logarithm is the inverse function of an exponential function and the exponential function is NEVER negative). When I send above reply to my friend he did understand that he was passing incorrect value to the function. As mentioned earlier the only way to fix this issue is finding incorrect value and avoid passing it to the function. Every mathematics function is different and there is not a single solution to identify erroneous value passed. If you are facing this error and not able to figure out the solution. Post a comment and I will do my best to figure out the solution. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Error Messages, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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  • Turn Non-Resizeable Windows into Rezieable Windows

    - by Asian Angel
    Are you frustrated with Windows app windows that can not be resized at all? Now you can apply some “attitude adjustment” and resize those windows with ResizeEnable. Before Everyone is familiar with the many app windows in their Windows OS that simply can not be resized. What you need is cooperation, not attitude. For our example we chose the “Taskbar and Start Menu Properties Window”…notice the cursor in the lower right corner. No resizing satisfaction available at all… After The program comes in a zip file with three files as shown here. Once you have unzipped the program place it in an appropriate “Program Files Folder”, create a shortcut, and you are ready to go. There will be a “System Tray Icon” with only two “Context Menu” items…“About & Quit”. Here is a quick look at the “About Window” that tells you exactly what ResizeEnable does. Notice that it does state that you may occasionally have a window that may not respond correctly. Now back to our “Taskbar and Start Menu Properties Window”. Notice the resizing cursor in the lower right corner….time for some fun! During our test the “Taskbar and Start Menu Properties Window” was suddenly a dream to resize. Daring to stretch the window even further…now that is what you call “stretching” the window out in comparison to its’ original size! Think of all the windows that will be much easier to work with now… Conclusion If you have been frustrated with non-resizeable windows then ResizeEnable will certainly bring a smile to your face as you watch those windows suddenly become a lot more cooperative. This is definitely one app that is worth adding to your system. Links Download ResizeEnable (zip file) Similar Articles Productive Geek Tips Quick Tip: Resize Any Textbox or Textarea in FirefoxTurn on Remote Desktop in Windows 7 or VistaSave 1-4% More Battery Life With Windows Vista Battery SaverQuick Tip: Disable Search History Display in Windows 7Turn Off Windows Explorer Click Sounds in Windows 7 or Vista TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional New Stinger from McAfee Helps Remove ‘FakeAlert’ Threats Google Apps Marketplace: Tools & Services For Google Apps Users Get News Quick and Precise With Newser Scan for Viruses in Ubuntu using ClamAV Replace Your Windows Task Manager With System Explorer Create Talking Photos using Fotobabble

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  • Toorcon14

    - by danx
    Toorcon 2012 Information Security Conference San Diego, CA, http://www.toorcon.org/ Dan Anderson, October 2012 It's almost Halloween, and we all know what that means—yes, of course, it's time for another Toorcon Conference! Toorcon is an annual conference for people interested in computer security. This includes the whole range of hackers, computer hobbyists, professionals, security consultants, press, law enforcement, prosecutors, FBI, etc. We're at Toorcon 14—see earlier blogs for some of the previous Toorcon's I've attended (back to 2003). This year's "con" was held at the Westin on Broadway in downtown San Diego, California. The following are not necessarily my views—I'm just the messenger—although I could have misquoted or misparaphrased the speakers. Also, I only reviewed some of the talks, below, which I attended and interested me. MalAndroid—the Crux of Android Infections, Aditya K. Sood Programming Weird Machines with ELF Metadata, Rebecca "bx" Shapiro Privacy at the Handset: New FCC Rules?, Valkyrie Hacking Measured Boot and UEFI, Dan Griffin You Can't Buy Security: Building the Open Source InfoSec Program, Boris Sverdlik What Journalists Want: The Investigative Reporters' Perspective on Hacking, Dave Maas & Jason Leopold Accessibility and Security, Anna Shubina Stop Patching, for Stronger PCI Compliance, Adam Brand McAfee Secure & Trustmarks — a Hacker's Best Friend, Jay James & Shane MacDougall MalAndroid—the Crux of Android Infections Aditya K. Sood, IOActive, Michigan State PhD candidate Aditya talked about Android smartphone malware. There's a lot of old Android software out there—over 50% Gingerbread (2.3.x)—and most have unpatched vulnerabilities. Of 9 Android vulnerabilities, 8 have known exploits (such as the old Gingerbread Global Object Table exploit). Android protection includes sandboxing, security scanner, app permissions, and screened Android app market. The Android permission checker has fine-grain resource control, policy enforcement. Android static analysis also includes a static analysis app checker (bouncer), and a vulnerablity checker. What security problems does Android have? User-centric security, which depends on the user to grant permission and make smart decisions. But users don't care or think about malware (the're not aware, not paranoid). All they want is functionality, extensibility, mobility Android had no "proper" encryption before Android 3.0 No built-in protection against social engineering and web tricks Alternative Android app markets are unsafe. Simply visiting some markets can infect Android Aditya classified Android Malware types as: Type A—Apps. These interact with the Android app framework. For example, a fake Netflix app. Or Android Gold Dream (game), which uploads user files stealthy manner to a remote location. Type K—Kernel. Exploits underlying Linux libraries or kernel Type H—Hybrid. These use multiple layers (app framework, libraries, kernel). These are most commonly used by Android botnets, which are popular with Chinese botnet authors What are the threats from Android malware? These incude leak info (contacts), banking fraud, corporate network attacks, malware advertising, malware "Hackivism" (the promotion of social causes. For example, promiting specific leaders of the Tunisian or Iranian revolutions. Android malware is frequently "masquerated". That is, repackaged inside a legit app with malware. To avoid detection, the hidden malware is not unwrapped until runtime. The malware payload can be hidden in, for example, PNG files. Less common are Android bootkits—there's not many around. What they do is hijack the Android init framework—alteering system programs and daemons, then deletes itself. For example, the DKF Bootkit (China). Android App Problems: no code signing! all self-signed native code execution permission sandbox — all or none alternate market places no robust Android malware detection at network level delayed patch process Programming Weird Machines with ELF Metadata Rebecca "bx" Shapiro, Dartmouth College, NH https://github.com/bx/elf-bf-tools @bxsays on twitter Definitions. "ELF" is an executable file format used in linking and loading executables (on UNIX/Linux-class machines). "Weird machine" uses undocumented computation sources (I think of them as unintended virtual machines). Some examples of "weird machines" are those that: return to weird location, does SQL injection, corrupts the heap. Bx then talked about using ELF metadata as (an uintended) "weird machine". Some ELF background: A compiler takes source code and generates a ELF object file (hello.o). A static linker makes an ELF executable from the object file. A runtime linker and loader takes ELF executable and loads and relocates it in memory. The ELF file has symbols to relocate functions and variables. ELF has two relocation tables—one at link time and another one at loading time: .rela.dyn (link time) and .dynsym (dynamic table). GOT: Global Offset Table of addresses for dynamically-linked functions. PLT: Procedure Linkage Tables—works with GOT. The memory layout of a process (not the ELF file) is, in order: program (+ heap), dynamic libraries, libc, ld.so, stack (which includes the dynamic table loaded into memory) For ELF, the "weird machine" is found and exploited in the loader. ELF can be crafted for executing viruses, by tricking runtime into executing interpreted "code" in the ELF symbol table. One can inject parasitic "code" without modifying the actual ELF code portions. Think of the ELF symbol table as an "assembly language" interpreter. It has these elements: instructions: Add, move, jump if not 0 (jnz) Think of symbol table entries as "registers" symbol table value is "contents" immediate values are constants direct values are addresses (e.g., 0xdeadbeef) move instruction: is a relocation table entry add instruction: relocation table "addend" entry jnz instruction: takes multiple relocation table entries The ELF weird machine exploits the loader by relocating relocation table entries. The loader will go on forever until told to stop. It stores state on stack at "end" and uses IFUNC table entries (containing function pointer address). The ELF weird machine, called "Brainfu*k" (BF) has: 8 instructions: pointer inc, dec, inc indirect, dec indirect, jump forward, jump backward, print. Three registers - 3 registers Bx showed example BF source code that implemented a Turing machine printing "hello, world". More interesting was the next demo, where bx modified ping. Ping runs suid as root, but quickly drops privilege. BF modified the loader to disable the library function call dropping privilege, so it remained as root. Then BF modified the ping -t argument to execute the -t filename as root. It's best to show what this modified ping does with an example: $ whoami bx $ ping localhost -t backdoor.sh # executes backdoor $ whoami root $ The modified code increased from 285948 bytes to 290209 bytes. A BF tool compiles "executable" by modifying the symbol table in an existing ELF executable. The tool modifies .dynsym and .rela.dyn table, but not code or data. Privacy at the Handset: New FCC Rules? "Valkyrie" (Christie Dudley, Santa Clara Law JD candidate) Valkyrie talked about mobile handset privacy. Some background: Senator Franken (also a comedian) became alarmed about CarrierIQ, where the carriers track their customers. Franken asked the FCC to find out what obligations carriers think they have to protect privacy. The carriers' response was that they are doing just fine with self-regulation—no worries! Carriers need to collect data, such as missed calls, to maintain network quality. But carriers also sell data for marketing. Verizon sells customer data and enables this with a narrow privacy policy (only 1 month to opt out, with difficulties). The data sold is not individually identifiable and is aggregated. But Verizon recommends, as an aggregation workaround to "recollate" data to other databases to identify customers indirectly. The FCC has regulated telephone privacy since 1934 and mobile network privacy since 2007. Also, the carriers say mobile phone privacy is a FTC responsibility (not FCC). FTC is trying to improve mobile app privacy, but FTC has no authority over carrier / customer relationships. As a side note, Apple iPhones are unique as carriers have extra control over iPhones they don't have with other smartphones. As a result iPhones may be more regulated. Who are the consumer advocates? Everyone knows EFF, but EPIC (Electrnic Privacy Info Center), although more obsecure, is more relevant. What to do? Carriers must be accountable. Opt-in and opt-out at any time. Carriers need incentive to grant users control for those who want it, by holding them liable and responsible for breeches on their clock. Location information should be added current CPNI privacy protection, and require "Pen/trap" judicial order to obtain (and would still be a lower standard than 4th Amendment). Politics are on a pro-privacy swing now, with many senators and the Whitehouse. There will probably be new regulation soon, and enforcement will be a problem, but consumers will still have some benefit. Hacking Measured Boot and UEFI Dan Griffin, JWSecure, Inc., Seattle, @JWSdan Dan talked about hacking measured UEFI boot. First some terms: UEFI is a boot technology that is replacing BIOS (has whitelisting and blacklisting). UEFI protects devices against rootkits. TPM - hardware security device to store hashs and hardware-protected keys "secure boot" can control at firmware level what boot images can boot "measured boot" OS feature that tracks hashes (from BIOS, boot loader, krnel, early drivers). "remote attestation" allows remote validation and control based on policy on a remote attestation server. Microsoft pushing TPM (Windows 8 required), but Google is not. Intel TianoCore is the only open source for UEFI. Dan has Measured Boot Tool at http://mbt.codeplex.com/ with a demo where you can also view TPM data. TPM support already on enterprise-class machines. UEFI Weaknesses. UEFI toolkits are evolving rapidly, but UEFI has weaknesses: assume user is an ally trust TPM implicitly, and attached to computer hibernate file is unprotected (disk encryption protects against this) protection migrating from hardware to firmware delays in patching and whitelist updates will UEFI really be adopted by the mainstream (smartphone hardware support, bank support, apathetic consumer support) You Can't Buy Security: Building the Open Source InfoSec Program Boris Sverdlik, ISDPodcast.com co-host Boris talked about problems typical with current security audits. "IT Security" is an oxymoron—IT exists to enable buiness, uptime, utilization, reporting, but don't care about security—IT has conflict of interest. There's no Magic Bullet ("blinky box"), no one-size-fits-all solution (e.g., Intrusion Detection Systems (IDSs)). Regulations don't make you secure. The cloud is not secure (because of shared data and admin access). Defense and pen testing is not sexy. Auditors are not solution (security not a checklist)—what's needed is experience and adaptability—need soft skills. Step 1: First thing is to Google and learn the company end-to-end before you start. Get to know the management team (not IT team), meet as many people as you can. Don't use arbitrary values such as CISSP scores. Quantitive risk assessment is a myth (e.g. AV*EF-SLE). Learn different Business Units, legal/regulatory obligations, learn the business and where the money is made, verify company is protected from script kiddies (easy), learn sensitive information (IP, internal use only), and start with low-hanging fruit (customer service reps and social engineering). Step 2: Policies. Keep policies short and relevant. Generic SANS "security" boilerplate policies don't make sense and are not followed. Focus on acceptable use, data usage, communications, physical security. Step 3: Implementation: keep it simple stupid. Open source, although useful, is not free (implementation cost). Access controls with authentication & authorization for local and remote access. MS Windows has it, otherwise use OpenLDAP, OpenIAM, etc. Application security Everyone tries to reinvent the wheel—use existing static analysis tools. Review high-risk apps and major revisions. Don't run different risk level apps on same system. Assume host/client compromised and use app-level security control. Network security VLAN != segregated because there's too many workarounds. Use explicit firwall rules, active and passive network monitoring (snort is free), disallow end user access to production environment, have a proxy instead of direct Internet access. Also, SSL certificates are not good two-factor auth and SSL does not mean "safe." Operational Controls Have change, patch, asset, & vulnerability management (OSSI is free). For change management, always review code before pushing to production For logging, have centralized security logging for business-critical systems, separate security logging from administrative/IT logging, and lock down log (as it has everything). Monitor with OSSIM (open source). Use intrusion detection, but not just to fulfill a checkbox: build rules from a whitelist perspective (snort). OSSEC has 95% of what you need. Vulnerability management is a QA function when done right: OpenVas and Seccubus are free. Security awareness The reality is users will always click everything. Build real awareness, not compliance driven checkbox, and have it integrated into the culture. Pen test by crowd sourcing—test with logging COSSP http://www.cossp.org/ - Comprehensive Open Source Security Project What Journalists Want: The Investigative Reporters' Perspective on Hacking Dave Maas, San Diego CityBeat Jason Leopold, Truthout.org The difference between hackers and investigative journalists: For hackers, the motivation varies, but method is same, technological specialties. For investigative journalists, it's about one thing—The Story, and they need broad info-gathering skills. J-School in 60 Seconds: Generic formula: Person or issue of pubic interest, new info, or angle. Generic criteria: proximity, prominence, timeliness, human interest, oddity, or consequence. Media awareness of hackers and trends: journalists becoming extremely aware of hackers with congressional debates (privacy, data breaches), demand for data-mining Journalists, use of coding and web development for Journalists, and Journalists busted for hacking (Murdock). Info gathering by investigative journalists include Public records laws. Federal Freedom of Information Act (FOIA) is good, but slow. California Public Records Act is a lot stronger. FOIA takes forever because of foot-dragging—it helps to be specific. Often need to sue (especially FBI). CPRA is faster, and requests can be vague. Dumps and leaks (a la Wikileaks) Journalists want: leads, protecting ourselves, our sources, and adapting tools for news gathering (Google hacking). Anonomity is important to whistleblowers. They want no digital footprint left behind (e.g., email, web log). They don't trust encryption, want to feel safe and secure. Whistleblower laws are very weak—there's no upside for whistleblowers—they have to be very passionate to do it. Accessibility and Security or: How I Learned to Stop Worrying and Love the Halting Problem Anna Shubina, Dartmouth College Anna talked about how accessibility and security are related. Accessibility of digital content (not real world accessibility). mostly refers to blind users and screenreaders, for our purpose. Accessibility is about parsing documents, as are many security issues. "Rich" executable content causes accessibility to fail, and often causes security to fail. For example MS Word has executable format—it's not a document exchange format—more dangerous than PDF or HTML. Accessibility is often the first and maybe only sanity check with parsing. They have no choice because someone may want to read what you write. Google, for example, is very particular about web browser you use and are bad at supporting other browsers. Uses JavaScript instead of links, often requiring mouseover to display content. PDF is a security nightmare. Executible format, embedded flash, JavaScript, etc. 15 million lines of code. Google Chrome doesn't handle PDF correctly, causing several security bugs. PDF has an accessibility checker and PDF tagging, to help with accessibility. But no PDF checker checks for incorrect tags, untagged content, or validates lists or tables. None check executable content at all. The "Halting Problem" is: can one decide whether a program will ever stop? The answer, in general, is no (Rice's theorem). The same holds true for accessibility checkers. Language-theoretic Security says complicated data formats are hard to parse and cannot be solved due to the Halting Problem. W3C Web Accessibility Guidelines: "Perceivable, Operable, Understandable, Robust" Not much help though, except for "Robust", but here's some gems: * all information should be parsable (paraphrasing) * if not parsable, cannot be converted to alternate formats * maximize compatibility in new document formats Executible webpages are bad for security and accessibility. They say it's for a better web experience. But is it necessary to stuff web pages with JavaScript for a better experience? A good example is The Drudge Report—it has hand-written HTML with no JavaScript, yet drives a lot of web traffic due to good content. A bad example is Google News—hidden scrollbars, guessing user input. Solutions: Accessibility and security problems come from same source Expose "better user experience" myth Keep your corner of Internet parsable Remember "Halting Problem"—recognize false solutions (checking and verifying tools) Stop Patching, for Stronger PCI Compliance Adam Brand, protiviti @adamrbrand, http://www.picfun.com/ Adam talked about PCI compliance for retail sales. Take an example: for PCI compliance, 50% of Brian's time (a IT guy), 960 hours/year was spent patching POSs in 850 restaurants. Often applying some patches make no sense (like fixing a browser vulnerability on a server). "Scanner worship" is overuse of vulnerability scanners—it gives a warm and fuzzy and it's simple (red or green results—fix reds). Scanners give a false sense of security. In reality, breeches from missing patches are uncommon—more common problems are: default passwords, cleartext authentication, misconfiguration (firewall ports open). Patching Myths: Myth 1: install within 30 days of patch release (but PCI §6.1 allows a "risk-based approach" instead). Myth 2: vendor decides what's critical (also PCI §6.1). But §6.2 requires user ranking of vulnerabilities instead. Myth 3: scan and rescan until it passes. But PCI §11.2.1b says this applies only to high-risk vulnerabilities. Adam says good recommendations come from NIST 800-40. Instead use sane patching and focus on what's really important. From NIST 800-40: Proactive: Use a proactive vulnerability management process: use change control, configuration management, monitor file integrity. Monitor: start with NVD and other vulnerability alerts, not scanner results. Evaluate: public-facing system? workstation? internal server? (risk rank) Decide:on action and timeline Test: pre-test patches (stability, functionality, rollback) for change control Install: notify, change control, tickets McAfee Secure & Trustmarks — a Hacker's Best Friend Jay James, Shane MacDougall, Tactical Intelligence Inc., Canada "McAfee Secure Trustmark" is a website seal marketed by McAfee. A website gets this badge if they pass their remote scanning. The problem is a removal of trustmarks act as flags that you're vulnerable. Easy to view status change by viewing McAfee list on website or on Google. "Secure TrustGuard" is similar to McAfee. Jay and Shane wrote Perl scripts to gather sites from McAfee and search engines. If their certification image changes to a 1x1 pixel image, then they are longer certified. Their scripts take deltas of scans to see what changed daily. The bottom line is change in TrustGuard status is a flag for hackers to attack your site. Entire idea of seals is silly—you're raising a flag saying if you're vulnerable.

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