We are in the process of writing a native windows app (MFC) that will be uploading some data to our web app. Windows app will allow user to login and after that it will periodically upload some data to our web app. Upload will be done via simple HTTP POST to our web app. The concern I'm having is how can we ensure that the upload actually came from our app, and not from curl or something like that. I guess we're looking at some kind of public/private key encryption here. But I'm not sure if we can somehow just embed a public key in our win app executable and be done with it. Or would that public key be too easy to extract and use outside of our app?
Anyway, we're building both sides (client and server) so pretty much anything is an option, but it has to work through HTTP(S). However, we do not control the execution environment of win (client) app, plus the user that is running the app on his/her system is the only one that stands to gain something by gaming the system.
Ultimately, it's not possible to prove the identity of an application this way when it's running on a machine you don't own. You could embed keys, play with hashes and checksums, but at the end of the day, anything that relies on code running on somebody else's machine can be faked. Keys can be extracted, code can be reverse-engineered- it's all security through obscurity.
Spend your time working on validation and data cleanup, and if you really want to secure something, secure the end-user with a client certificate. Anything else is just a waste of time and a false sense of security.
About the best you could do would be to use HTTPS with client certificates. Presumably with WinHTTP's interface.
But I'm not sure if we can somehow just embed a public key in our win app executable and be done with it.
If the client is to be identifying itself to the server, it would have to be the private key embedded.
Or would that be too easy to extract and use outside of our app?
If you don't control the client app's execution environment, anything your app can do can be analysed, automated and reproduced by an attacker that does control that environment.
You can put obfuscatory layers around the communications procedure if you must, but you'll never fix the problem. Multiplayer games have been trying to do this for years to combat cheating, but in the end it's just an obfuscation arms race that can never be won. Blizzard have way more resources than you, and they can't manage it either.
You have no control over the binaries once your app is distributed. If all the signing and encryption logic reside in your executable it can be extracted. Clever coders will figure out the code and build interoperable systems when there's enough motivation to do so. That's why DRM doesn't work.
A complex system tying a key to the MAC address of a PC for instance is sure to fail.
Don't trust a particular executable or system but trust your users. Entrust each of them with a private key file protected by a passphrase and explain to them how that key identify them as submitters of contents on your service.
Since you're controlling the client, you might as well embed the key in the application, and make sure the users don't have read access to the application image - you'll need to separate the logic to 2 tiers - 1 that the user runs, the other that connects to the service over HTTP(S) - since the user will always have read access to an application he's running.
If I understand correctly, the data is sent automatically after the user logs on - this sounds like only the service part is needed.
Related
I have experience developing software and web applications and I have decided to do some freelance work on the side. Well, I met with my first client and they are requesting a relatively simple, custom system that (without being long winded) tracks client’s paperwork as it progresses through the business’s different manual processes. It is a small business that has about 10 employees, but all of the employees will interact with the client’s paperwork, therefore everyone would need access to the new system. When I say ‘track’ I literally mean that the employees will ‘check as complete’ on a simple page the increases a progress bar at different stages for the paperwork. Now I am %110 capable of coding the custom system that meets their needs, but I am unsure about how I should go about doing it.
The information that is being tracked in the new system and stored in the DB is confidential information that they are very protective of. My main question is how should I be developing this to be as secure as I can?
-They have their own server in house, so should I develop an application (VB and SQL) for the server and require employees to log on remotely to use it? Can more than one person access/use the application at a time?
-Or should I develop a web application (ASP.Net/VB and SQL) that is only accessible on their network to their employees? They plan to expand offices, could they set up a VPN to access the site?
I’m leaning towards a web application, but I have not done too much in term of security. Basically I’m looking for pros and cons for either option or any suggestions on what I should.
PS, stackoverflow is awesome! Long time user, first time poster!
If you want to develop using vb & sql you have to consider that:
You need to have real ip
Your system will communicate threw certain port and you have to handle the security measure for letting certain port opened in your server.
You should have good knowledge in network programming
If you want to develop using asp.net you have to consider that:
in case only office employees will use the system, you can develop against users in Active Directory and for outside users with username and password with SSL connection or vpn
for preventing more than one person access the file you can simply add column 'locked' in case file is being used.
Well im not a web fan (I suck) ive seen too many security issues go with it...i.e Lulzsec, but i do very much love VB apps.
So I would definetely recommend a VB app connected to a MSSQL database (coz it's easy to configure and havent seen any security exploits yet),my Chinese friend told me there is a way to access MySQL free databases.Now, allow remote access but make sure your Windows Firewall is also configured properly do look at all angles of security.
If I remember well there is an option in MSSQL to specify the IP addresses or is it MAC addresses that can access the DB so maybe input all of the 10 employees' IP addresses assuming they are static,if they are dynamic (DHCP) don't bother. And ask them to make the IP address of the server where you will host the DB on static.
If only 10 employees use the DB then limit the connections to 10. For now develop this when it comes to VPN you can make a Remote version of the App im sure that will come later right now focus on the basics. Also use Dotfuscator when you are publishing the app I heard it is very good.N also im suggesting the document/work order is received at the reception so that user will check in the document with specifics...if they are passing on the work order to the next user they should select the user and then THAT user may enter some sort of verification code unique to the user...im sure you can envision the rest from here. Now do I also get a cut from this?lol
I've been doing the same for years now, and I always take the website side, this days I go width ASP.NET MVC 4, it's easier, everything in their place and extremely easier to test and maintain.
The web application has a very big advantage to any standalone windows application, you deploy and upgrade only one application instead to maintain all the different versions once you start deploying windows apps, and they are harder to debug once you start to having different machines with different versions and so on...
so, Web or Win app = Web app, always!
All you need is a server that run IIS and set it up for using Active Directory (Visual Studio has that project already, simply create an ASP.NET MVC and choose the "intranet" template), it will set up everything for you, and all you need later is tweak the Active Directory connection string.
I also use a self-signed SSL to protect data between client and server, as I also make the apps available outside the office without VPN needed, as long as they login with their secure AD credentials.
And... audit everything into a secondary database, every action performed by a user since they login until they logout, every view, update or creating data witch .NET makes it simple if you create your Logging method to simple log messages and Stack messages on errors.
This will greatly benefit your employer and you when something goes wrong.
I would say to go with web application. Advantage using web application is, if they want to expand bussiness .. same can you do with you WebApp. But choose .Net over VB, going with latest techonology will help you resolve current challanges.
I am developing a flex 4.5 web based application and I need to make sure if the client chooses a certain level of security, each user can log only from an authorized computer.
So the question is how can I get some unique computer information? Anything like HDD serial number, CPU specifications, motherboard information, even the user that is logged into the Operating System can do.
So far the information on the web isn't giving me much hope that this can be achieved, but I had to ask.
Thanks in advance.
I suppose the only option available for web application is to create unique id from fields of flash.system.Capabilities class.
Other strategy which can be used is to generate unique UID in process of computer's authorization and then store it in local storage using SharedObject. Then web app tries to read authorization data from SharedObject on web app start. If there is no such data computer isn't authorized.
Richard is right. For security, unique identifying information is not available for applications running through Flash Player. You could write an Active X control (for IE) or a plugin (for Mozilla based browsers) to obtain additional information for your app if users (and their IT administrators) allow it. Information available will vary depending on the browser and operating system the user is running.
Adobe Air, on the other hand, allows access to additional network information including MAC address in the NetworkInfo class. Maybe it's worth considering an installed client app for users who require the additional security. Take a look at: http://www.adobe.com/devnet/air/flex/articles/retrieving_network_interfaces.html
This is not easy using a browser based Flex application, but there are some workarounds.
The browser based Flash Player can communicate with an AIR app on the desktop using localconnection. So, you could create an AIR app that utilizes NativeProcess to retrieve your machine specific information.
You could also use NativeProcess from a AIR app without using the browser at all.
A third option would be to install an application server on the client machine and have the browser based app communicate with the server to retrieve the client information.
I consider most of these options too difficult to be practical, but it depends on how important this feature is to you.
The Flash Player security sandbox will not let you read anything unique about the system on which the SWF is running, so I'm afraid this is not possible. The closest you will get is likely Capabilities.serverString along with maybe IP address, but the serverString property just lists all the capabilities of the client, which is obviously not a unique thing, and also might change from time to time for the same computer.
Warning: my knowledge of server-side scripting is limited to say the least.
This isn't a technical solution, but rather a different approach to your problem.
An alternative solution to would be to inspect the raw packet at the server in order to obtain data such as the IP and MAC address. Based on this the server can then deny or allow the login attempt.
I am used to working on embedded web servers running on micro controllers where C-based black magic is rather common, so I am not sure if this is possible or practical in a more traditional environment.
So I'm making a app for a bank, but it doesnt manage very important data. I have two problems, it will run over a VERY large LAN network protected by all kinds of security(antivirus and firewalls) and the bandwidth in certain regions is as low as 56kbps.(Its a desktop app with a web server backend connected by web services)
From the security point of view all I want is to prevent someone from executing the web services from some other source or app results in change in the database . I'm thinking of each desktop app installed with a install code, this will be hashed and required as a parameter for every function call and will act as an authentication ticket? Is this good enough? Are they better SIMPLER means?
For performance, how do I measure or know if the web service will send and receive data at a decent rate?
Thanks
Gideon
Assuming you are on a windows domain. You could configure the server to use windows authentication and restrict the users which can access the web service.
For performance measuring - asp.net will show you a sample request and response if you hit the web service from a browser, you can work out the site of a message and use the bandwidth to calculate how long it should take. You could also call the web service and use the stopwatch class to measure the time it takes.
I would prefer assigning usernames and passwords. Either way, the user can disclose their code to someone else. And either the user or a recipient can access the app using other programs (there's no way to prevent someone extracting an install code). But if you assign usernames, they are more likely to take personal responsibility for what happens using the authorization.
I want to make a secure website using ASP.NET, but when I publish it, the domain administrator can see all the data stored in my database (SQL Server). I want to hide my data and code from the domain administrator too. Are there any procedures to do that? Please give me the address of a good domain I can use, which will give me all administrative power of my website (Domain owner also cannot access my databases and files.) Thanks for your suggestion.
Have you looked at: SQL Server 2008 Transparent Data Encryption?
Also:
SQL Server 2008 Transparent Data Encryption
Understanding Transparent Data Encryption (TDE)
Have you considered using a Virtual Private Server? I believe with a VPS you should be able to have complete control over who has access to what at the operating system level.
You can encrypt data, but there's no way to protect code (especially not web-facing code), but frankly the question doesn't make sense - if you have trust issues with someone you have an implicit trust relationship with then you need to find a different provider.
If you don't trust anyone (personal psychology not withstanding) you need to host it yourself.
Addendum: look at it from the other way round, why would you host something for someone without being able to inspect it for security and even legal concerns?
If you want total security there's quite a few things you need to implement:
As others have said you need physical encryption of your database. Merely blocking them from accessing the database is not enough because they have access to the physical database files and can use tools on them to access the data directly.
You will want to use web.config encryption
Walkthrough: Encrypting Configuration Information Using Protected Configuration
How To: Encrypt Configuration Sections in ASP.NET 2.0 Using DPAPI
This is rather questionable security however since it requires a key container to be installed upon the server it would be arguably achievable for a nefarious administration to copy your key and then use it to manually decrypt your web.config. To protect yourself further than that you would need to create a secured web service (secured both for message transport, SSL, and secured message that the content itself is encrypted inside the SSL transport tunnel, see WCF services security) that your application constantly talks to for protected data like the login users for the sql server database and then apply rotating passwords to make it if they intercepted one password that it might not be valid anymore if it's been rotated.
After this point you will need to use source code protection that includes decompilation protection and code obfuscation. This will add a layer of protection from prohibiting viewing the source of your application directly for information about how else you protect your application (this will only go so far to stop a sophisticated cracker though).
All in all at this point you've achieved nearly the highest level of code/data security you can inside a hosted environment but this goes back to the core problem. If you have concerns that the system operator is nefarious then all of these protections even can still be beaten if the admin is skilled enough and has enough motivation to do it.
If you need protection above and behind this you would really want to look at colocation hosting or at the very least dedicated server hosting that would allow you to apply encryption at the operating system level as this protects you from the most effective brute strength attacks which involve just ripping out hard drives from a machine and spraying ram with air duster upside down to freeze it and then attempt to steal encryption keys from the ram itself disconnected from the server.
Having security that makes you immune (or nearly immune) to this kind of attack basically requires using TrueCrypt for native encryption of your file system where you do not have it cache the keys/key files in memory. At this point the only last part of security left is to host at a reputable data center like ThePlanet or Rackspace that has 24/7 electronic surveillance that it would be nearly impossible for a nefarious employee to be able to compromise your server without video recordings of it occuring.
Remove the BUILTIN\Administrators group from the sysadmin role - obviously this can only be done by a server admin, but in a proper environment, it is possible for domain admins to only be able to maintain servers nad not see data.
In 2008, the default is to not include this.
As for code, you can obfuscate your DLLs, but there is no complete way to hide code from someone who can access the filesystem.
You won't be able to hide the source code, but you do have some options to make it less inviting to admins:
obfuscate - deter people from knowing what is happening syntactically. While they can follow the code and eventually figure it out (if they want), it requires more effort. After all, with enough effort and know-how, anything can be cracked.
encrypt - because the web page needs to be decrypted by the server, the server needs to have a key to decrypt it. This key needs to be stored in a file that the server (and thus admin) has access to. Using some obfuscation, you can try and hide this (again), but any places there is a symmetric encryption, a superuser has the ability to get at it.
Note:
Any time something is encrypted, it will most likely require a decrypt to use/view. The process will be a negative performance impact.
When things are encrypted, especially from an admin perspective, it is essentially an invitation calling for alarm; it creates curiosity. If it's data, that's one thing, but code should not need to be encrypted where there is trust. It's like saying that you have something you want to hide, generally meaning something "bad" that you don't want found out.
My company has a website product (ASP.NET) which is sold to customers. It means we don't host the website. They install it on their server and run it in the intranet.
I need to implement some sort of copy protection mechanism so that not everyone ends up installing the website. It has following aspects:
It has to be completely software based (no dongles).
Hiding usage information in registry or some folder in c:\ (basically outside virtual directory) is not an option for a website
Please can you suggest any scheme/method?
One suggestion is to use some kind of web service running, of course you need to have a main server to do so. In this server you can have some of your clients servers data (IP of the authorized servers, CPU and Motherboard ID's, and other important data).
This web service has to run some important logic of the program and return a value to the authorized servers. If the data of autorization sent by the client doesn't match, the server do will not execute the routine.
Of course I assume that this side of the logic is included in a DLL in the application and not in plain code.
A technique that worked well for a buddy of mine was to install a web bug on an administrative page which would report back to their server. You can monitor when and where the application is installed. It could be easily removed, but won't by most customers.
Simple, easy to do, and works relatively well.
Something you could try. Compile binaries for each client, obfuscate the code, lock the site down to a single domain. If its an internal app the domain might be something like "productname.clientname.internal". The app checks the domain of all the incoming requests, refuses anything that doesn't match.
As already pointed out by jeffamaphone: people will find ways around it, but it's enough to 'slow down' those not super determined.
[disclaimer]I sell the product I am recommending.[/disclaimer]
Take a look at DeployLX. You can add licensing to your web based application to require one of a couple different options.
Hardware based locking so it can only be used on one machine.
Domain based locking so it's tied to a specific domain name.
IP based locking to tie it to an IP address.
License server locking to that your app checks in periodically with a centralized web service.
It's pretty flexible and should let you create a balance between protection and not frustrating your users.