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  • How to write Java-like enums in C++ ?

    - by Rahul G
    Coming from Java background, I find C++'s enums very lame. I wanted to know how to write Java-like enums (the ones in which the enum values are objects, and can have attributes and methods) in C++. As an example, translate the following Java code (a part of it, sufficient to demonstrate the technique) to C++ : public enum Planet { MERCURY (3.303e+23, 2.4397e6), VENUS (4.869e+24, 6.0518e6), EARTH (5.976e+24, 6.37814e6), MARS (6.421e+23, 3.3972e6), JUPITER (1.9e+27, 7.1492e7), SATURN (5.688e+26, 6.0268e7), URANUS (8.686e+25, 2.5559e7), NEPTUNE (1.024e+26, 2.4746e7); private final double mass; // in kilograms private final double radius; // in meters Planet(double mass, double radius) { this.mass = mass; this.radius = radius; } private double mass() { return mass; } private double radius() { return radius; } // universal gravitational constant (m3 kg-1 s-2) public static final double G = 6.67300E-11; double surfaceGravity() { return G * mass / (radius * radius); } double surfaceWeight(double otherMass) { return otherMass * surfaceGravity(); } public static void main(String[] args) { if (args.length != 1) { System.err.println("Usage: java Planet <earth_weight>"); System.exit(-1); } double earthWeight = Double.parseDouble(args[0]); double mass = earthWeight/EARTH.surfaceGravity(); for (Planet p : Planet.values()) System.out.printf("Your weight on %s is %f%n", p, p.surfaceWeight(mass)); } } Any hep would be greatly appreciated! Thanks!

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  • PowerShell Script to Enumerate SharePoint 2010 or 2013 Permissions and Active Directory Group Membership

    - by Brian T. Jackett
    Originally posted on: http://geekswithblogs.net/bjackett/archive/2013/07/01/powershell-script-to-enumerate-sharepoint-2010-or-2013-permissions-and.aspx   In this post I will present a script to enumerate SharePoint 2010 or 2013 permissions across the entire farm down to the site (SPWeb) level.  As a bonus this script also recursively expands the membership of any Active Directory (AD) group including nested groups which you wouldn’t be able to find through the SharePoint UI.   History     Back in 2009 (over 4 years ago now) I published one my most read blog posts about enumerating SharePoint 2007 permissions.  I finally got around to updating that script to remove deprecated APIs, supporting the SharePoint 2010 commandlets, and fixing a few bugs.  There are 2 things that script did that I had to remove due to major architectural or procedural changes in the script. Indenting the XML output Ability to search for a specific user    I plan to add back the ability to search for a specific user but wanted to get this version published first.  As for indenting the XML that could be added but would take some effort.  If there is user demand for it (let me know in the comments or email me using the contact button at top of blog) I’ll move it up in priorities.    As a side note you may also notice that I’m not using the Active Directory commandlets.  This was a conscious decision since not all environments have them available.  Instead I’m relying on the older [ADSI] type accelerator and APIs.  It does add a significant amount of code to the script but it is necessary for compatibility.  Hopefully in a few years if I need to update again I can remove that legacy code.   Solution    Below is the script to enumerate SharePoint 2010 and 2013 permissions down to site level.  You can also download it from my SkyDrive account or my posting on the TechNet Script Center Repository. SkyDrive TechNet Script Center Repository http://gallery.technet.microsoft.com/scriptcenter/Enumerate-SharePoint-2010-35976bdb   001 002 003 004 005 006 007 008 009 010 011 012 013 014 015 016 017 018 019 020 021 022 023 024 025 026 027 028 029 030 031 032 033 034 035 036 037 038 039 040 041 042 043 044 045 046 047 048 049 050 051 052 053 054 055 056 057 058 059 060 061 062 063 064 065 066 067 068 069 070 071 072 073 074 075 076 077 078 079 080 081 082 083 084 085 086 087 088 089 090 091 092 093 094 095 096 097 098 099 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 ########################################################### #DisplaySPWebApp8.ps1 # #Author: Brian T. Jackett #Last Modified Date: 2013-07-01 # #Traverse the entire web app site by site to display # hierarchy and users with permissions to site. ########################################################### function Expand-ADGroupMembership {     Param     (         [Parameter(Mandatory=$true,                    Position=0)]         [string]         $ADGroupName,         [Parameter(Position=1)]         [string]         $RoleBinding     )     Process     {         $roleBindingText = ""         if(-not [string]::IsNullOrEmpty($RoleBinding))         {             $roleBindingText = " RoleBindings=`"$roleBindings`""         }         Write-Output "<ADGroup Name=`"$($ADGroupName)`"$roleBindingText>"         $domain = $ADGroupName.substring(0, $ADGroupName.IndexOf("\") + 1)         $groupName = $ADGroupName.Remove(0, $ADGroupName.IndexOf("\") + 1)                                     #BEGIN - CODE ADAPTED FROM SCRIPT CENTER SAMPLE CODE REPOSITORY         #http://www.microsoft.com/technet/scriptcenter/scripts/powershell/search/users/srch106.mspx         #GET AD GROUP FROM DIRECTORY SERVICES SEARCH         $strFilter = "(&(objectCategory=Group)(name="+($groupName)+"))"         $objDomain = New-Object System.DirectoryServices.DirectoryEntry         $objSearcher = New-Object System.DirectoryServices.DirectorySearcher         $objSearcher.SearchRoot = $objDomain         $objSearcher.Filter = $strFilter         # specify properties to be returned         $colProplist = ("name","member","objectclass")         foreach ($i in $colPropList)         {             $catcher = $objSearcher.PropertiesToLoad.Add($i)         }         $colResults = $objSearcher.FindAll()         #END - CODE ADAPTED FROM SCRIPT CENTER SAMPLE CODE REPOSITORY         foreach ($objResult in $colResults)         {             if($objResult.Properties["Member"] -ne $null)             {                 foreach ($member in $objResult.Properties["Member"])                 {                     $indMember = [adsi] "LDAP://$member"                     $fullMemberName = $domain + ($indMember.Name)                                         #if($indMember["objectclass"]                         # if child AD group continue down chain                         if(($indMember | Select-Object -ExpandProperty objectclass) -contains "group")                         {                             Expand-ADGroupMembership -ADGroupName $fullMemberName                         }                         elseif(($indMember | Select-Object -ExpandProperty objectclass) -contains "user")                         {                             Write-Output "<ADUser>$fullMemberName</ADUser>"                         }                 }             }         }                 Write-Output "</ADGroup>"     } } #end Expand-ADGroupMembership # main portion of script if((Get-PSSnapin -Name microsoft.sharepoint.powershell) -eq $null) {     Add-PSSnapin Microsoft.SharePoint.PowerShell } $farm = Get-SPFarm Write-Output "<Farm Guid=`"$($farm.Id)`">" $webApps = Get-SPWebApplication foreach($webApp in $webApps) {     Write-Output "<WebApplication URL=`"$($webApp.URL)`" Name=`"$($webApp.Name)`">"     foreach($site in $webApp.Sites)     {         Write-Output "<SiteCollection URL=`"$($site.URL)`">"                 foreach($web in $site.AllWebs)         {             Write-Output "<Site URL=`"$($web.URL)`">"             # if site inherits permissions from parent then stop processing             if($web.HasUniqueRoleAssignments -eq $false)             {                 Write-Output "<!-- Inherits role assignments from parent -->"             }             # else site has unique permissions             else             {                 foreach($assignment in $web.RoleAssignments)                 {                     if(-not [string]::IsNullOrEmpty($assignment.Member.Xml))                     {                         $roleBindings = ($assignment.RoleDefinitionBindings | Select-Object -ExpandProperty name) -join ","                         # check if assignment is SharePoint Group                         if($assignment.Member.XML.StartsWith('<Group') -eq "True")                         {                             Write-Output "<SPGroup Name=`"$($assignment.Member.Name)`" RoleBindings=`"$roleBindings`">"                             foreach($SPGroupMember in $assignment.Member.Users)                             {                                 # if SharePoint group member is an AD Group                                 if($SPGroupMember.IsDomainGroup)                                 {                                     Expand-ADGroupMembership -ADGroupName $SPGroupMember.Name                                 }                                 # else SharePoint group member is an AD User                                 else                                 {                                     # remove claim portion of user login                                     #Write-Output "<ADUser>$($SPGroupMember.UserLogin.Remove(0,$SPGroupMember.UserLogin.IndexOf("|") + 1))</ADUser>"                                     Write-Output "<ADUser>$($SPGroupMember.UserLogin)</ADUser>"                                 }                             }                             Write-Output "</SPGroup>"                         }                         # else an indivdually listed AD group or user                         else                         {                             if($assignment.Member.IsDomainGroup)                             {                                 Expand-ADGroupMembership -ADGroupName $assignment.Member.Name -RoleBinding $roleBindings                             }                             else                             {                                 # remove claim portion of user login                                 #Write-Output "<ADUser>$($assignment.Member.UserLogin.Remove(0,$assignment.Member.UserLogin.IndexOf("|") + 1))</ADUser>"                                                                 Write-Output "<ADUser RoleBindings=`"$roleBindings`">$($assignment.Member.UserLogin)</ADUser>"                             }                         }                     }                 }             }             Write-Output "</Site>"             $web.Dispose()         }         Write-Output "</SiteCollection>"         $site.Dispose()     }     Write-Output "</WebApplication>" } Write-Output "</Farm>"      The output from the script can be sent to an XML which you can then explore using the [XML] type accelerator.  This lets you explore the XML structure however you see fit.  See the screenshot below for an example.      If you do view the XML output through a text editor (Notepad++ for me) notice the format.  Below we see a SharePoint site that has a SharePoint group Demo Members with Edit permissions assigned.  Demo Members has an AD group corp\developers as a member.  corp\developers has a child AD group called corp\DevelopersSub with 1 AD user in that sub group.  As you can see the script recursively expands the AD hierarchy.   Conclusion    It took me 4 years to finally update this script but I‘m happy to get this published.  I was able to fix a number of errors and smooth out some rough edges.  I plan to develop this into a more full fledged tool over the next year with more features and flexibility (copy permissions, search for individual user or group, optional enumerate lists / items, etc.).  If you have any feedback, feature requests, or issues running it please let me know.  Enjoy the script!         -Frog Out

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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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  • 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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  • Which is more maintainable -- boolean assignment via if/else or boolean expression?

    - by Bret Walker
    Which would be considered more maintainable? if (a == b) c = true; else c = false; or c = (a == b); I've tried looking in Code Complete, but can't find an answer. I think the first is more readable (you can literally read it out loud), which I also think makes it more maintainable. The second one certainly makes more sense and reduces code, but I'm not sure it's as maintainable for C# developers (I'd expect to see this idiom more in, for example, Python).

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  • What type of command can I use for shortcut assignment?

    - by navie
    We all know that Ubuntu 12 has a shortcut mapper under "Keyboard" utility. I wonder when it asks for "command" in the new shortcut dialog, what type of command can I use? I used to think that commands in terminal can also be used here, but it seems xdotool is not like that. btw, if xdotool is not the right solution, how to map a key combination to a another key? for e.g.: alt+j to Down arrow key Thank you

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  • Why is the value of __name__ changing after assignment to sys.modules[__name__]?

    - by martineau
    While trying to do something similar to what's in the ActiveState recipe titled Constants in Python by Alex Martelli, I ran into an unexpected side-effect that assigning a class instance to an entry in sys.modules apparently has in Python 2.7 -- namely that doing so apparent changes the value of __name__ to None as illustrated in the following code fragment: class _test(object): pass import sys print '__name__: %r' % __name__ # __name__: '__main__' sys.modules[__name__] = _test() print '__name__: %r' % __name__ # __name__: None if __name__ == '__main__': # never executes... import test print "done" I'd like to understand why this is happening. I don't believe it was that way in Python 2.6 and earlier versions since I have some older code where apparently the if __name__ == '__main__': conditional worked as expected following the assignment (but no longer does). FWIW, I also noticed that the name _class is getting rebound from a class object to None, too, after the assignment. Also seems odd to me that they're being rebound to 'None' rather than disappearing altogether... Update: I'd like to add that any workarounds for achieving the effect of if __name__ == '__main__':, given what happens would be greatly appreciated. TIA!

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  • Can KVM CPU assignment count differ from physical hosts CPU count?

    - by javano
    I have read this question. I knew already that I could for example, have a quad core machine with four guests each having two vCPUs. As they don't all be require 100% CPU usage all the time, the scheduler would handle this for me. My question is about how this relates to a fail-over or migration situation; If host1 has two dual-core CPUs, and I assign guest1 four vCPUs (so it accessed all four physical cores), what will happen if I try and migrate it to host2 which only has one dual-core CPU? Can qemu-kvm emulate more vCPUs than there are physical? Or would I have to shut down the virtual machine, change the CPU assignment, migrate it, and then boot it back up (so no live migration)? Many thanks.

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  • CodeModel help needed for right-hand singleton.getinstance() assignment.

    - by antarti
    I've been able to generate 99% of what I need with the CodeModel API, but I am stumped here... Using the various "directXX" methods does not add import statements to the generated code, and I can work without the "directXXX" type of methods except for one place in a generated class. Suppose I desire a generated method like: /** * Copies data from this Value-Obj instance, to the returned PERSON instance. * * @return PERSON * */ public PERSON mapVOToPERSON() throws MappingException { Mapper mapper = (com.blah.util.MapperSingleton.getMapperInstance()); return mapper.map(this, PERSON.class); } You can see the right hand of the Mapper assignment in parens. Emitting the entire package+class was the only way I could find to just declare "SomeSingleton.someMethod()" on the right hand side and have the generated code compile. Without the MapperSingleton being added to the object model, there is no import generated... Questions: 1) Is there a way to force an import to be generated? 2) How to declare an expression that gives me the right side of the Mapper assignment within the object model (so that an import of MapperSingleton gets generated. Any help appreciated...

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  • In this example where is the C++ assignment operator used rather than the copy constructor ?

    - by Bill Forster
    As part of an ongoing process of trying to upgrade my C++ skills, I am trying to break some old habits. My old school C programmer inclination is to write this; void func( Widget &ref ) { Widget w; // default constructor int i; for( i=0; i<10; i++ ) { w = ref; // assignment operator // do stuff that modifies w } } This works well. But I think the following is closer to best practice; void func( Widget &ref ) { for( int i=0; i<10; i++ ) { Widget w = ref; // ?? // do stuff that modifies w } } With my Widget class at least, this works fine. But I don't fully understand why. I have two theories; 1) The copy constructor runs 10 times. 2) The copy constructor runs once then the assignment operator runs 9 times. Both of these trouble me a little. 2) in particular seems artificial and wrong. Is there a third possibility that I am missing ?

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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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  • Bullet Physic: Transform body after adding

    - by Mathias Hölzl
    I would like to transform a rigidbody after adding it to the btDiscreteDynamicsWorld. When I use the CF_KINEMATIC_OBJECT flag I am able to transform it but it's static (no collision response/gravity). When I don't use the CF_KINEMATIC_OBJECT flag the transform doesn't gets applied. So how to I transform non-static objects in bullet? DemoCode: btBoxShape* colShape = new btBoxShape(btVector3(SCALING*1,SCALING*1,SCALING*1)); /// Create Dynamic Objects btTransform startTransform; startTransform.setIdentity(); btScalar mass(1.f); //rigidbody is dynamic if and only if mass is non zero, otherwise static bool isDynamic = (mass != 0.f); btVector3 localInertia(0,0,0); if (isDynamic) colShape->calculateLocalInertia(mass,localInertia); btDefaultMotionState* myMotionState = new btDefaultMotionState(); btRigidBody::btRigidBodyConstructionInfo rbInfo(mass,myMotionState,colShape,localInertia); btRigidBody* body = new btRigidBody(rbInfo); body->setCollisionFlags(body->getCollisionFlags()|btCollisionObject::CF_KINEMATIC_OBJECT); body->setActivationState(DISABLE_DEACTIVATION); m_dynamicsWorld->addRigidBody(body); startTransform.setOrigin(SCALING*btVector3( btScalar(0), btScalar(20), btScalar(0) )); body->getMotionState()->setWorldTransform(startTransform);

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  • Opposite Force to Apply to a Collided Rigid Body?

    - by Milo
    I'm working on the physics for my GTA2-like game so I can learn more about game physics. The collision detection and resolution are working great. I'm now just unsure how to compute the force to apply to a body after it collides with a wall. My rigid body looks like this: /our simulation object class RigidBody extends Entity { //linear private Vector2D velocity = new Vector2D(); private Vector2D forces = new Vector2D(); private float mass; private Vector2D v = new Vector2D(); //angular private float angularVelocity; private float torque; private float inertia; //graphical private Vector2D halfSize = new Vector2D(); private Bitmap image; private Matrix mat = new Matrix(); private float[] Vector2Ds = new float[2]; private Vector2D tangent = new Vector2D(); private static Vector2D worldRelVec = new Vector2D(); private static Vector2D relWorldVec = new Vector2D(); private static Vector2D pointVelVec = new Vector2D(); private static Vector2D acceleration = new Vector2D(); public RigidBody() { //set these defaults so we don't get divide by zeros mass = 1.0f; inertia = 1.0f; setLayer(LAYER_OBJECTS); } protected void rectChanged() { if(getWorld() != null) { getWorld().updateDynamic(this); } } //intialize out parameters public void initialize(Vector2D halfSize, float mass, Bitmap bitmap) { //store physical parameters this.halfSize = halfSize; this.mass = mass; image = bitmap; inertia = (1.0f / 20.0f) * (halfSize.x * halfSize.x) * (halfSize.y * halfSize.y) * mass; RectF rect = new RectF(); float scalar = 10.0f; rect.left = (int)-halfSize.x * scalar; rect.top = (int)-halfSize.y * scalar; rect.right = rect.left + (int)(halfSize.x * 2.0f * scalar); rect.bottom = rect.top + (int)(halfSize.y * 2.0f * scalar); setRect(rect); } public void setLocation(Vector2D position, float angle) { getRect().set(position.x,position.y, getWidth(), getHeight(), angle); rectChanged(); } public Vector2D getPosition() { return getRect().getCenter(); } @Override public void update(float timeStep) { doUpdate(timeStep); } public void doUpdate(float timeStep) { //integrate physics //linear acceleration.x = forces.x / mass; acceleration.y = forces.y / mass; velocity.x += (acceleration.x * timeStep); velocity.y += (acceleration.y * timeStep); //velocity = Vector2D.add(velocity, Vector2D.scalarMultiply(acceleration, timeStep)); Vector2D c = getRect().getCenter(); v.x = getRect().getCenter().getX() + (velocity.x * timeStep); v.y = getRect().getCenter().getY() + (velocity.y * timeStep); setCenter(v.x, v.y); forces.x = 0; //clear forces forces.y = 0; //angular float angAcc = torque / inertia; angularVelocity += angAcc * timeStep; setAngle(getAngle() + angularVelocity * timeStep); torque = 0; //clear torque } //take a relative Vector2D and make it a world Vector2D public Vector2D relativeToWorld(Vector2D relative) { mat.reset(); Vector2Ds[0] = relative.x; Vector2Ds[1] = relative.y; mat.postRotate(JMath.radToDeg(getAngle())); mat.mapVectors(Vector2Ds); relWorldVec.x = Vector2Ds[0]; relWorldVec.y = Vector2Ds[1]; return relWorldVec; } //take a world Vector2D and make it a relative Vector2D public Vector2D worldToRelative(Vector2D world) { mat.reset(); Vector2Ds[0] = world.x; Vector2Ds[1] = world.y; mat.postRotate(JMath.radToDeg(-getAngle())); mat.mapVectors(Vector2Ds); worldRelVec.x = Vector2Ds[0]; worldRelVec.y = Vector2Ds[1]; return worldRelVec; } //velocity of a point on body public Vector2D pointVelocity(Vector2D worldOffset) { tangent.x = -worldOffset.y; tangent.y = worldOffset.x; pointVelVec.x = (tangent.x * angularVelocity) + velocity.x; pointVelVec.y = (tangent.y * angularVelocity) + velocity.y; return pointVelVec; } public void applyForce(Vector2D worldForce, Vector2D worldOffset) { //add linear force forces.x += worldForce.x; forces.y += worldForce.y; //add associated torque torque += Vector2D.cross(worldOffset, worldForce); } @Override public void draw( GraphicsContext c) { c.drawRotatedScaledBitmap(image, getPosition().x, getPosition().y, getWidth(), getHeight(), getAngle()); } public Vector2D getVelocity() { return velocity; } public void setVelocity(Vector2D velocity) { this.velocity = velocity; } } The way it is given force is by the applyForce method, this method considers angular torque. I'm just not sure how to come up with the vectors in the case where: RigidBody hits static entity RigidBody hits other RigidBody that may or may not be in motion. Would anyone know a way (without too complex math) that I could figure out the opposite force I need to apply to the car? I know the normal it is colliding with and how deep it collided. My main goal is so that say I hit a building from the side, well the car should not just stay there, it should slowly rotate out of it if I'm more than 45 degrees. Right now when I hit a wall I only change the velocity directly which does not consider angular force. Thanks!

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  • juju bootstrap key error?

    - by mxdog
    I followed the guides the best as i could. there is some information missing like do as root or as regular user ..formatting, quotes no quotes..what the password or paraphrase for ssh should be ..couple other trivial things. that im sure add up to where im at (stuck!) so i have a working mass server on mx-nas-01 and 3 nodes and have been trying to get juju to start. I have tried this as both root and my regular account, sudo no-sudo and here is the output i get from juju bootstrap (however i try it) I don't know if this could be a host,domain,account issue or what i will mention i did have to shut off my dhcp server and install masq (all defaults) to get the maas pxe to work for the nodes mxdog@mx-nas-01:/$ juju bootstrap Traceback (most recent call last): File "/usr/bin/juju", line 8, in main(sys.argv[1:]) File "/usr/lib/python2.7/dist-packages/juju/control/init.py", line 183, in main env_config.load_or_write_sample() File "/usr/lib/python2.7/dist-packages/juju/environment/config.py", line 229, in load_or_write_sample self.load() File "/usr/lib/python2.7/dist-packages/juju/environment/config.py", line 115, in load self.parse(file.read(), path) File "/usr/lib/python2.7/dist-packages/juju/environment/config.py", line 138, in parse config = SCHEMA.coerce(config, []) File "/usr/lib/python2.7/dist-packages/juju/lib/schema.py", line 266, in coerce new_dict[k] = self.schema[k].coerce(v, path) File "/usr/lib/python2.7/dist-packages/juju/lib/schema.py", line 233, in coerce new_subvalue = self.value_schema.coerce(subvalue, value_path) File "/usr/lib/python2.7/dist-packages/juju/lib/schema.py", line 301, in coerce return self.schemas[selected].coerce(value, path) KeyError: 'mass' environments: maas: type: mass mass-server: http://192.168.0.30:80/MAAS mass-oauth: tDRdtJeEKVARBh93eT:N5dK5HSZBsA45cBdx9:S8wMNrfkT9PeYvQN9YrnbHGxmKARv8vb admin-secret: ########## default-series: precise

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  • Elliptical orbit modeling

    - by Nathon
    I'm playing with orbits in a simple 2-d game where a ship flies around in space and is attracted to massive things. The ship's velocity is stored in a vector and acceleration is applied to it every frame as appropriate given Newton's law of universal gravitation. The point masses don't move (there's only 1 right now) so I would expect an elliptical orbit. Instead, I see this: I've tried with nearly circular orbits, and I've tried making the masses vastly different (a factor of a million) but I always get this rotated orbit. Here's some (D) code, for context: void accelerate(Vector delta) { velocity = velocity + delta; // Velocity is a member of the ship class. } // This function is called every frame with the fixed mass. It's a // method of the ship's. void fall(Well well) { // f=(m1 * m2)/(r**2) // a=f/m // Ship mass is 1, so a = f. float mass = 1; Vector delta = well.position - loc; float rSquared = delta.magSquared; float force = well.mass/rSquared; accelerate(delta * force * mass); }

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  • Best practise to send mass email within application (ASP.NET MVC 2, C#)?

    - by gurdan
    Whats the best way to implement mass email sending feature within web app? Two major cases: Email messages for separate registered users depending on their activities (just sending short reminders to user for ex about new posts in his created topic) "Send email for all registered users" functionality, it will be nice to have feature for system administrator to send some messages for all registered users. Of course adding all emails to recipient isn't the way we can go, because email addresses for each user are anonimous. As i understand for case nr1 there is no problem just create some email message via System.Net.Mail by creating new mail message and sending it... but what about case nr 2??? i guess smth like this: foreach(var emailAddress in emailAddresses) { MailMessage mail = new MailMessage(); mail.From = new MailAddress("[email protected]"); mail.To.Add(emailAddress); mail.Subject = "test"; mail.Body = "test"; SmtpClient smtp = new SmtpClient("smtp.gmail.com", 587); smtp.Send(mail); } isn't the good way :) so the question is what is the best way to achieve this ? btw we have no possiblity to deploy some serive for email sending, this should be integrated into web application.

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  • Array inside of Arrays; Java (Help with Lab Assignment)

    - by Adam
    We are working on a lab assignment for my CS&E class and I think I can ask this question without going into detail of the entire lab requirements, but is it possible for an array to be inside of an array? For example, would this work: int [] arrayOne = new int[3]; arrayOne[0] = Start of an array If this is possible how do you go about doing it?

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