Search Results

Search found 27912 results on 1117 pages for 'computer security'.

Page 214/1117 | < Previous Page | 210 211 212 213 214 215 216 217 218 219 220 221  | Next Page >

• Sanitizing CSS in Rails

  - by Erik

  Hello! I want to allow the users of a web app that I'm building to write their own CSS in order to customize their profile page. However I am aware of this opening up for many security risks, i e background: url('javascript:alert("Got your cookies! " + document.cookies'). Hence I am looking for a solution to sanitize the CSS while still allowing as much CSS functionality as possible for my users. So my questions if anyone anyone knows of a gem or a plugin to handles this? I've googled my brains out already so any tips would be really appreciated!

  Read the article

• "Untrusted packages could compromise your system's security." appears while trying to install anything

  - by maria

  Hi I've freshly installed Ubuntu 10.4 on a new computer. I'm trying to install on it application I need (my old computer is broken and I have to send it to the service). I've managed to install texlive and than I can't install anything else. All software I want to have is what I have succesfuly installed on my old computer (with the same version of Ubuntu), so I don't understand, why terminal says (sorry, the terminal talks half English, half Polish, but I hope it's enough): maria@marysia-ubuntu:~$ sudo aptitude install emacs Czytanie list pakietów... Gotowe Budowanie drzewa zaleznosci Odczyt informacji o stanie... Gotowe Reading extended state information Initializing package states... Gotowe The following NEW packages will be installed: emacs emacs23{a} emacs23-bin-common{a} emacs23-common{a} emacsen-common{a} 0 packages upgraded, 5 newly installed, 0 to remove and 0 not upgraded. Need to get 23,9MB of archives. After unpacking 73,8MB will be used. Do you want to continue? [Y/n/?] Y WARNING: untrusted versions of the following packages will be installed! Untrusted packages could compromise your system's security. You should only proceed with the installation if you are certain that this is what you want to do. emacs emacs23-bin-common emacsen-common emacs23-common emacs23 Do you want to ignore this warning and proceed anyway? To continue, enter "Yes"; to abort, enter "No" I was trying to install other editors as well, with the same result. As I decided that I might be sure that I know the package I want to install is secure, finaly I've entered "Yes". The installation ended succesfuly, but editor don't understand any .tex file (.tex files are for sure fine): this is pdfTeX, Version 3.1415926-1.40.10 (TeX Live 2009/Debian) restricted \write18 enabled. entering extended mode (./Szarfi.tex ! Undefined control sequence. l.2 \documentclass {book} ? What's more, I've realised that in Synaptic Manager there is no package which would be marked as supported by Canonical... Any tips? Thanks in advance

  Read the article

• Mutual Information / Entropy Calculation Help

  - by Fillip

  Hi, Hoping someone can give me some pointers with this entropy problem. Say X is chosen randomly from the uniform integer distribution 0-32 (inclusive). I calculate the entropy, H(X) = 32 bits, as each Xi has equal probability of occurring. Now, say the following pseudocode executes. int r = rand(0,1); // a random integer 0 or 1 r = r * 33 + X; How would I work out the mutual information between the two variables r and X? Mutual Information is defined as I(X; Y) = H(X) - H(X|Y) but I don't really understand how to apply the conditional entropy H(X|Y) to this problem. Thanks

  Read the article

• php Form to Email sanitizing

  - by Jacob

  Hi, im using the following to send a contact us type form, iv looked into security and only found that you need to protect the From: bit of the mail function, as ive hardcoded this does that mean the script is spamproof / un-hijackable $tenantname = $_POST['tenan']; $tenancyaddress = $_POST['tenancy']; $alternativename = $_POST['alternativ //and a few more //then striptags on each variable $to = "[email protected]"; $subject = "hardcoded subject here"; $message = "$tenantname etc rest of posted data"; $from = "[email protected]"; $headers = "From: $from"; mail($to,$subject,$message,$headers);

  Read the article

• How to deal with users who think their computer could think?

  - by DavRob60

  Along my career, I had to deal with users who think their computer could think: My computer hates me! or He just do this so he could laugh at me! This is often a joke, but some users are serious. It's easy when I know the causes of the problem, but when it's unexpected behavior it's more complicated. In those cases, I usually turn it as a joke, putting that on the fault of moon phases and tide, but they are likely to prefer their explanations. Do you have any tricks to deal with those users?

  Read the article

• How do I tell which account is trying to access an ASP.NET web service?

  - by Andrew Lewis

  I'm getting a 401 (access denied) calling a method on an internal web service. I'm calling it from an ASP.NET page on our company intranet. I've checked all the configuration and it should be using integrated security with an account that has access to that service, but I'm trying to figure out how to confirm which account it's connecting under. Unfortunately I can't debug the code on the production network. In our dev environment everything is working fine. I know there has to be a difference in the settings, but I'm at a loss with where to start. Any recommendations?

  Read the article

• how to merge file lines having the same first word in python?

  - by user1377135

  I have written a program to merge lines in a file containing the same first word in python. However I am unable to get the desired output. Can anyone please suggest me the mistake in my program? input "file.txt" line1: a b c line2: a b1 c1 line3: d e f line4: i j k line5: i s t line6: i m n ` output a b c a b1 c1 d e f i j k i s t i m n my code a = [line.split() for line in open('file.txt')] L=[] for i in range(0,len(a)): j=i while True: if a[j][0] == a[j+1][0]: L.append(a[j]) L.append(a[j+1]) j=j+2 else: print a[i] print L break

  Read the article

• Which is the best algorithm to "Estimate and Visulize 2d skeleton using Opencv" from the drawn conto

  - by kumar

  Which is the best algorithm to "Estimate and Visulize 2d skeleton using Opencv" from the drawn contour Is the Recursive Centroid algorithm the Best? any reference links or docs please provide

  Read the article

• How do you avoid an invalid search space in a genetic algorithm?

  - by Dave

  I am developing a GA for a school project and I've noticed that upon evaluating my functions for fitness, an individual is equivalent to its inverse. For example, the set (1, 1, -1, 1) is equivalent to (-1, -1, 1, -1). To shrink my search space and reach a solution more efficiently, how can I avoid my crossovers from searching in this second half of the search space?

  Read the article

• Learning material on SAT (Boolean Satisfiability Problem)

  - by Jules

  What are good documents to read on SAT (Boolean satisfiability problem) solvers. I have not been able to find good material via Google. The documents I found were either birds eye view, too advanced or corrupted PDF files... Which papers/documents do you recommend to learn about the algorithms in modern practical SAT solvers?

  Read the article

• Reliably detect caller domain over cURL request?

  - by Utkanos

  OK so server-side security is not my forte. Basically, I'm building a service which users may use (via an SDK) only on the domain they stipulated when they signed up. The SDK calls my web service over cURL in PHP. Would I be right in thinking I cannot reliably detect the caller domain, i.e. enforce that it is the same domain they stipulated when signing up? cURL of course sends this over headers, but headers can always (?) be faked. Is there a better course of action to enforce domain for this sort of thing? (NB I'm already using an API key, too - it's just I wanted to restrict domain, too) Thanks in advance

  Read the article

• Task vs. process, is there really any difference?

  - by DASKAjA

  Hi there, I'm studying for my final exams in my CS major on the subject distributed systems and operating systems. I'm in the need for a good definition for the terms task, process and threads. So far I'm confident that a process is the representation of running (or suspended, but initiated) program with its own memory, program counter, registers, stack, etc (process control block). Processes can run threads which share memory, so that communication via shared memory is possible in contrast to processes which have to communicate via IPC. But what's the difference between tasks and process. I often read that they're interchangable and that the term task isn't used anymore. Is that really true?

  Read the article

• My computer boots up with Ubuntu: How can I tell what's on my hard disk?

  - by Larry Harson

  I've acquired an old laptop (Acer TravelMate 4050 with an Italian keyboard) that boots up with the following options: Ubuntu, with Linux 3.0.0-12-generic Ubuntu, with Linux 3.0.0-12-generic (recovery mode) Memory test (memtest86+) Memory test (memtest86+, serial console 115200) When I choose the first option, the screen just goes blank with a flashing cursor. But I can go into grub command mode by typing 'c'. Now, I want to know what operating system is installed, and the files stored on my computer, so how do I do this? What can I do to maximise the use of this computer in its current state?

  Read the article

• What is the best way to implement this composite GetHashCode()

  - by Frank Krueger

  I have a simple class: public class TileName { int Zoom, X, Y; public override bool Equals (object obj) { var o = obj as TileName; return (o != null) && (o.Zoom == Zoom) && (o.X == X) && (o.Y == Y); } public override int GetHashCode () { return (Zoom + X + Y).GetHashCode(); } } I was curious if I would get a better distribution of hash codes if I instead did something like: public override int GetHashCode () { return Zoom.GetHashCode() + X.GetHashCode() + Y.GetHashCode(); } This class is going to be used as a Dictionary key, so I do want to make sure there is a decent distribution.

  Read the article

• Good way to identify similar images?

  - by Nick

  I've developed a simple and fast algorithm in PHP to compare images for similarity. Its fast (~40 per second for 800x600 images) to hash and a unoptimised search algorithm can go through 3,000 images in 22 mins comparing each one against the others (3/sec). The basic overview is you get a image, rescale it to 8x8 and then convert those pixels for HSV. The Hue, Saturation and Value are then truncated to 4 bits and it becomes one big hex string. Comparing images basically walks along two strings, and then adds the differences it finds. If the total number is below 64 then its the same image. Different images are usually around 600 - 800. Below 20 and extremely similar. Are there any improvements upon this model I can use? I havent looked at how relevant the different components (hue, saturation and value) are to the comparison. Hue is probably quite important but the others? To speed up searches I could probably split the 4 bits from each part in half, and put the most significant bits first so if they fail the check then the lsb doesnt need to be checked at all. I dont know a efficient way to store bits like that yet still allow them to be searched and compared easily. I've been using a dataset of 3,000 photos (mostly unique) and there havent been any false positives. Its completely immune to resizes and fairly resistant to brightness and contrast changes.

  Read the article

• Html encoding in MVC input

  - by fearofawhackplanet

  I'm working through NerdDinner and I'm a bit confused about the following section... First they've added a form for creating a new dinner, with a bunch of textboxes delcared like: <%= Html.TextArea("Description") %> They then show two ways of binding form input to the model: [AcceptVerbs(HttpVerbs.Post)] public ActionResult Create() { Dinner dinner = new Dinner(); UpdateModel(dinner); ... } or: [AcceptVerbs(HttpVerbs.Post)] public ActionResult Create(Dinner dinner) { ... } Ok, great, that all looks really easy so far. Then a bit later on they say: It is important to always be paranoid about security when accepting any user input, and this is also true when binding objects to form input. You should be careful to always HTML encode any user-entered values to avoid HTML and JavaScript injection attacks Huh? MVC is managing the data binding for us. Where/how are you supposed to do the HTML encoding?

  Read the article

• Reason to use more cookies than just a session hash for authentication?

  - by dierre

  I usually hang out in a community using vBulletin as its bulletin board. I was looking at what this software saves as cookie in my browser. As you can see it saves 6 cookies. Amongst them, what I consider to be important for authentification are: ngivbsessionhash: hash of the current session ngivbpassword: hash of the password ngivbuserid: user's id Those are my assumptions of course. I don't know for sure if ngilastactivity and ngilastvisit are used for the same reason. My question is: why use all these cookie for authentication? My guess would be that maybe generating a session hash would be to easy so using the hashedpassword and userid adds security but what about cookie spoofing? I'm basically leaving on the client all fundamental informations. What do you think?

  Read the article

• Approximate timings for various operations on a "typical desktop PC" anno 2010

  - by knorv

  In the article "Teach Yourself Programming in Ten Years" Peter Norvig (Director of Research, Google) gives the following approximate timings for various operations on a typical 1GHz PC back in 2001: execute single instruction = 1 nanosec = (1/1,000,000,000) sec fetch word from L1 cache memory = 2 nanosec fetch word from main memory = 10 nanosec fetch word from consecutive disk location = 200 nanosec fetch word from new disk location (seek) = 8,000,000 nanosec = 8 millisec What would the corresponding timings be for your definition of a typical PC desktop anno 2010?

  Read the article

• Are .NET's regular expressions Turing complete?

  - by Robert

  Regular expressions are often pointed to as the classical example of a language that is not Turning complete. For example "regular expressions" is given in as the answer to this SO question looking for languages that are not Turing complete. In my, perhaps somewhat basic, understanding of the notion of Turning completeness, this means that regular expressions cannot be used check for patterns that are "balanced". Balanced meaning have an equal number of opening characters as closing characters. This is because to do this would require you to have some kind of state, to allow you to match the opening and closing characters. However the .NET implementation of regular expressions introduces the notion of a balanced group. This construct is designed to let you backtrack and see if a previous group was matched. This means that a .NET regular expressions: ^(?<p>a)*(?<-p>b)*(?(p)(?!))$ Could match a pattern that: ab aabb aaabbb aaaabbbb ... etc. ... Does this means .NET's regular expressions are Turing complete? Or are there other things that are missing that would be required for the language to be Turing complete?

  Read the article

• Detecting Markers Using OpenCV

  - by Hamza Yerlikaya

  I am trying to detect various objects containing colored markers, so a red blue green marker identifies object A, and a red blue red marker identifies object B. My problem is I can't use template matching cause objects can be rotated, currently I am thinking about check for each color then find the object by checking the distance between colors but it seems inefficient, so my question is there a better way to do this?

  Read the article

• What is the function from which all other functions can be derived?

  - by ChrisD

  I seem to remember reading about a function that could be used to make all other functions. Does anyone know what it is? And how could such a function be used? I can't remember where I read it and my google-fu is not strong enough.

  Read the article

• Why are GPUs cheaper than CPUs? [closed]

  - by Lucas

  What are the technological reasons whereby GPUs are cheaper than CPUs?

  Read the article

• How to do motion tracking of a object using video

  - by Niroshan

  Could someone direct me to a tutorial or guide me how to track motion of a object moving with 6 DOF. I am planing to use a video stream of a moving toy car. I want to calculate displacement and rotation angle of the toy car. I came across some research papers but couldn't find any libraries to the job. Is there a way to do this using OpenCV or Matlab or some other freely available software? Thank you

  Read the article

• How are CD Keys generated?

  - by The Rook

  CD Keys are the defacto-standard as an anti-piracy measure. To be honest this strikes me as Security Though Obscurity, although I really have no idea how CD Keys are generated. What is a good (secure) example of CD Key generation? What cryptographic primitive (if any) are they using? Is it a message digest? If so what data would they be hashing? What methods do developers employ to make it difficult for crackers to build their own key generators?

  Read the article

• Disadvantages of hard coding credentials? What's the resolution?

  - by SeeBees

  I am building a Sharepoint web part that will be used by all users. The web part connects to a web service which needs credentials with higher privileges than common users. I hard coded credentials in the web part's code. query.Credentials = new System.Net.NetworkCredential("username", "password", "domain"); query is an instance of the web service class This may not be a good approach. In regard with security, source code of the web apart is available to people who are not allowed to see the credential. This is bad enough, But is there any other drawback of this approach? How to prevent hard coding credentials into the source code? Thanks

  Read the article

< Previous Page | 210 211 212 213 214 215 216 217 218 219 220 221  | Next Page >