I have developed a tool that loads in an configuration file at runtime. Some of the values are encrypted with an AES key.
The tool will be scheduled to run on a regular basis from a remote machine. What is an acceptable way to provide the decryption key to the program. It has a command line interface which I can pass it through. I can currently see three options
Provide the full key via CLI, meaning the key is available in the clear at OS config level (i.e. CronJob)
Hardcode the key into the binary via source code. Not a good idea for a number of reasons. (Decompiling and less portable)
Use a combination of 1 and 2 i.e. Have a base key in exe and then accept partial key via CLI. This way I can use the same build for multiple machines, but it doesn't solve the problem of decompiling the exe.
It is worth noting that I am not too worried about decompiling the exe to get key. If i'm sure there are ways I could address via obfuscation etc.
Ultimately if I was really conscious I wouldn't be storing the password anywhere.
I'd like to hear what is considered best practice. Thanks.
I have added the Go tag because the tool is written in Go, just in case there is a magical Go package that might help, other than that, this question is not specific to a technology really.
UPDATE:: I am trying to protect the key from external attackers. Not the regular physical user of the machine.
Best practice for this kind of system is one of two things:
A sysadmin authenticates during startup, providing a password at the console. This is often extremely inconvenient, but is pretty easy to implement.
A hardware device is used to hold the credential. The most common and effective are called HSMs (Hardware Security Modules). They come in all kinds of formats, from USB keys to plug-in boards to external rack-mounted devices. HSMs come with their own API that you would need to interface with. The main feature of an HSM is that it never divulges its key, and it has physical safeguards to protect against it being extracted. Your app sends it some data and it signs the data and returns it. That proves that that the hardware module was connected to this machine.
For specific OSes, you can make use of the local secure credential storage, which can provide some reasonable protection. Windows and OS X in particular have these, generally keyed to some credential the admin is required to type at startup. I'm not aware of a particularly effective one for Linux, and in general this is pretty inconvenient in a server setting (because of manual sysadmin intervention).
In every case that I've worked on, an HSM was the best solution in the end. For simple uses (like starting an application), you can get them for a few hundred bucks. For a little more "roll-your-own," I've seen them as cheap as $50. (I'm not reviewing these particularly. I've mostly worked with a bit more expensive ones, but the basic idea is the same.)
Related
One suggested way to run jobs is to save context parameters in properties files.
Like this one:
#
#Wed Dec 16 18:23:03 CET 2015
MySQL_AdditionalParams=noDatetimeStringSync\=true
MySQL_Port=3306
MySQL_Login=root
MySQL_Password=secret_password_to_cipher
MySQL_Database=talend MySQL_Server=localhost
This is really easy and useful, but the issue with this is that passwords are saved in clear.
So I'm looking for ways to do easily ciphering.
Here are 2 very insteresting questions already discussed in Stack overflow about password ciphering technics:
Encrypt passwords in configuration files
Securing passwords in properties file
But they are Java native and I'm searching for a better Talend integration. I've already tried different ways in my Talend jobs:
Simple obfuscation using base64 encoding of passwords
Using tEncrypt and tDecrypt components from the forge
Using Jasypt ot JavaXCrypto librairies
Using pwdstore routine from the forge
All these technics are described in a tutorial (in french, sorry) explaining how to crypt passwords in Talend
But another issue is encountered: keys used to cipher/uncipher are always in clear, so if you know good ways to address this point I'll be glad to experiment it.
Fundamentally, anything an application can reach can be reached by somebody breaking in into the system/taking over control of the application.
Even if you use obfuscation (such as base64 or more advanced), or real encryption where the keys are available (even if they too might be obfuscated).
So essentially there is no good enough way to do what you seek to do and worse: it simply cannot exist.
So what do you do instead ?
1. Limit the rights
MySQL_Login=root is a big problem ... a compromise of the application will lead to an immediate compromise of the database (and its data).
So, limit the rights to what is absolutely needed for the application.
This should really be done and is quite easy to achieve.
2. Separate user and admin level access
If certain things are only needed after user interaction, you can use secrets provided by the user (e.g. a password of the user can give a hash and that can be xor-ed with and get you a key that's not always present in the application nor configuration files).
You can use this e.g. to separate out permissions in two levels: the normal user level which only has the bare minimal rights to make the application work for the average user, (but e.g. not the application management rights that allow managing the application itself), and use the secrets kept by the user to keep (pert of) the key outside of the application while there's no admin logged in into the administrative part of the application.
This is rarely done to be honest, nor all that easy.
But even with all that you essentially have to consider the access to e.g. the database to be compromised if the application is compromised.
That's also why data such as application user password should not (must not) be stored in the database without proper precautions.
what's the proper way to capture biometric information (pressure, speed...) by signing with a stylus on a canvas developed in a JSP web Page
Alright, since no one else has attempted to answer this question, I shall elaborate on my comment and opefully it will serve as an answer to others as well.
First, Java Server Pages (JSP) is a server-side language. It is meant to run on the web-server and not on the user's browser. The same goes for other server-side languages like PHP and ASP.
So a server-side language is not able to directly interact with devices (keyboard, scanners, cameras, etc). Only when the data is submitted by the browser or client program, the server receives it for processing.
For a device to receive input, there are two key pieces of software needed.
The device driver: which must be installed on the user's machine
The application program to capture inputs and do any processing.
If either one is missing, the device cannot function. And then there's another issues. Depending on the device, there's various feedback from the driver/API that should go back to the application that reads it. For example, if a fingerprint scan was not very successful for some reason, the scanner should tell this to the user. So again, there's the need for interactivity between the device and the user's application.
Thus, using any server-side language is out of the question for such applicatoins.
Now, in order to make this possible, you may use a client-side program. Here are some options.
A native application in VB, C/C++, Pascal or other language. If this is an option, the user must install this application on their computer.
A browser-based program. This can be a program created using JAVA (not Javascript or JSP), or ActiveX component. ActiveX is largely OS/browser dependent. And the TRUTH is that even Java is not truly platform independent when it comes to different operating systems. There are some technical differences that you'll need to look into. But for the most part of interactivity and high-level operations, yes, Java is more platform-independent than the others. But on a personal note, Java is my worst language. I try not to use it anywhere anymore. That's a different story.
In both options above, every client machine must have their own proprietory drivers and often some sort of API for browser integration.
A year or so ago, I had to program a Bio-Mini fingerprint scanner using VB. It was all sweet in the beginning. Then due to the restrictions of networkability and concurrent usage, the drivers/SDK could not take the load and things were going wrong. By the way, the drivers/SDK were meant for MS-Access. Knowing that the DB was the problem, I started to port this to MySQL. And it was a severe climb from there. I had to do a near-rewrite of the SDK for capturing and comparing data using arrays in VB. And to make things worst, the device was changed and things went wrong again. But do note that the new device was from the same manufacturer.
So keep in mind that even a simple change like that can cause a problem.
My program needs to decrypt an encrypted file after it starts up to load data it requires to function. This data cannot be available to the user.
I'm not a cryptography expert, so what is the best way to protect hardcoded passphrases and other tidbits of data from users, debugging software and disassembling software?
I understand that this is probably bad practice but it's essential for me (at least for now).
If there are other ways to protect my data from the above 3, could you let me know what those are?
Short answer: you can't. Once the software is on the user's disk, a sufficiently smart and determined user will be able to extract the secret data from it.
For a longer answer, see "Storing secrets in software" on the security.SE blog.
what is the best way to protect hardcoded passphrases and other
tidbits of data from users, debugging software and disassembling
software?
Request the password from the user and don't hardcode the passphrase. This is the ONLY way to be safe.
If you can't do that and must be hardcoded in the app then all bets are off.
The simplest thing you can do (if you don't have the luxury to do something elaborate which will only delay the inevidable) is to delegate the responsibility to the user of the system.
I mean explicitely state that you software is as secure as the "machine" it runs.
If the attacker has access to start pocking around the file system then your app would be the user's least of concerns
In my experience this type of questions are often motivated by either of four reasons:
Your application is connecting to a restricted remote service, such as a database server.
You do not want your users to mess with configuration settings, which in turn do not really have to be kept confidential as long as they are unmodified.
Copy protection of your own software.
Copy protection of data.
Like Illmari Karonen wrote in his answer, you can't do exactly what you are asking for, and this means in particular that 3 & 4 cannot be solved by cryptography alone.
However, if your reason for asking is either 1 or 2, you have ended up asking the questions you do, because you have made some bad decisions earlier in your design process. For instance, in case of 1, you should not make a restricted service accessible from systems you do not trust completely. The typical safe solution is to introduce a middle tier that is the only client to your restricted resource, and which you can make public.
In case of 2, the best solution is often to use exactly the same logic for checking your configuration files (or registry settings or what ever) when they are loaded at start up, as you use for checking consistency when the user enters them using your preferred configuration user interface. If you spot an inconsistency, just bring up your configuration UI and highlight the problem.
I know there are plenty of questions here already about this topic (I've read through as many as I could find), but I haven't yet been able to figure out how best to satisfy my particular criteria. Here are the goals:
The ASP.NET application will run on a few different web servers, including localhost workstations for development. This means encrypting web.config using a machine key is out. Each "type" or environment of web server (dev, test, prod) has its own corresponding database (dev, test, prod). We want to separate these connection strings so that a developer working on the "dev" code is not able to see any "prod" connection string passwords, nor allow these production passwords to ever get deployed to the wrong server or committed to SVN.
The application will should be able to decide which connection string to attempt to use based on the server name (using a switch statement). For example, "localhost" and "dev.example.com" will should know to use the DevDatabaseConnectionString, "test.example.com" will use the TestDatabaseConnectionString, and "www.example.com" will use the ProdDatabaseConnectionString, for example. The reason for this is to limit the chance for any deployment accidents, where the wrong type of web server connects to the wrong database.
Ideally, the exact same executables and web.config should be able to run on any of these environments, without needing to tailor or configure each environment separately every time that we deploy (something that seems like it would be easy to forget/mess up one day during a deployment, which is why we moved away from having just one connectionstring that has to be changed on each target). Deployment is currently accomplished via FTP. Update: Using "build events " and revising our deployment procedures is probably not a bad idea.
We will not have command-line access to the production web server. This means using aspnet_regiis.exe to encrypt the web.config is out. Update: We can do this programmatically so this point is moot.
We would prefer to not have to recompile the application whenever a password changes, so using web.config (or db.config or whatever) seems to make the most sense.
A developer should not be able to get to the production database password. If a developer checks the source code out onto their localhost laptop (which would determine that it should be using the DevDatabaseConnectionString, remember?) and the laptop gets lost or stolen, it should not be possible to get at the other connection strings. Thus, having a single RSA private key to un-encrypt all three passwords cannot be considered. (Contrary to #3 above, it does seem like we'd need to have three separate key files if we went this route; these could be installed once per machine, and should the wrong key file get deployed to the wrong server, the worst that should happen is that the app can't decrypt anything---and not allow the wrong host to access the wrong database!)
UPDATE/ADDENDUM: The app has several separate web-facing components to it: a classic ASMX Web Services project, an ASPX Web Forms app, and a newer MVC app. In order to not go mad having the same connection string configured in each of these separate projects for each separate environment, it would be nice to have this only appear in one place. (Probably in our DAL class library or in a single linked config file.)
I know this is probably a subjective question (asking for a "best" way to do something), but given the criteria I've mentioned, I'm hoping that a single best answer will indeed arise.
Thank you!
Integrated authentication/windows authentication is a good option. No passwords, at least none that need be stored in the web.config. In fact, it's the option I prefer unless admins have explicity taken it away from me.
Personally, for anything that varies by machine (which isn't just connection string) I put in a external reference from the web.config using this technique: http://www.devx.com/vb2themax/Tip/18880
When I throw code over the fence to the production server admin, he gets a new web.config, but doesn't get the external file-- he uses the one he had earlier.
you can have multiple web servers with the same encrypted key. you would do this in machine config just ensure each key is the same.
..
one common practice, is to store first connection string encrypted somewhere on the machine such as registry. after the server connects using that string, it will than retrieve all other connection strings which would be managed in the database (also encrypted). that way connection strings can be dynamically generated based on authorization requirements (requestor, application being used, etc) for example the same tables can be accessed with different rights depending on context and users/groups
i believe this scenario addresses all (or most?) of your points..
(First, Wow, I think 2 or 3 "quick paragraphs" turned out a little longer than I'd thought! Here I go...)
I've come to the conclusion (perhaps you'll disagree with me on this) that the ability to "protect" the web.config whilst on the server (or by using aspnet_iisreg) has only limited benefit, and is perhaps maybe not such a good thing as it may possibly give a false sense of security. My theory is that if someone is able to obtain access to the filesystem in order to read this web.config in the first place, then they also probably have access to create their own simple ASPX file which can "unprotect" it and reveal its secrets to them. But if unauthorized people are trouncing around in your filesystem—well… then you have bigger problems at hand, so my whole concern is now moot! 1
I also realize that there isn’t a foolproof way to securely hide passwords within a DLL either, as they can eventually be disassembled and discovered, perhaps by using something like ILDASM. 2 An additional measure of security obscurity can be obtained by obfuscating and encrypting your binaries, such as by using Dotfuscator, but this isn’t to be considered “secure.” And again, if someone has read access (and likely write access too) to your binaries and filesystem, you’ve again got bigger problems at hand methinks.
To address the concerns I mentioned about not wanting the passwords to live on developer laptops or in SVN: solving this through a separate “.config” file that does not live in SVN is (now!) the blindingly obvious choice. Web.config can live happily in source control, while just the secret parts do not. However---and this is why I’m following up on my own question with such a long response---there are still a few extra steps I’ve taken to try and make this if not any more secure, then at least a little bit more obscure.
Connection strings we want to try to keep secret (those other than the development passwords) won’t ever live as plain text in any files. These are now encrypted first with a secret (symmetric) key---using, of course, the new ridiculous Encryptinator(TM)! utility built just for this purpose---before they get placed in a copy of a “db.config” file. The db.config is then just uploaded only to its respective server. The secret key is compiled directly into the DAL’s dll, which itself would then (ideally!) be further obfuscated and encrypted with something like Dotfuscator. This will hopefully keep out any casual curiosity at the least.
I’m not going to worry much at all about the symmetric "DbKey" living in the DLLs or SVN or on developer laptops. It’s the passwords themselves I’ll keep out. We do still need to have a “db.config” file in the project in order to develop and debug, but it has all fake passwords in it except for development ones. Actual servers have actual copies with just their own proper secrets. The db.config file is typically reverted (using SVN) to a safe state and never stored with real secrets in our subversion repository.
With all this said, I know it’s not a perfect solution (does one exist?), and one that does still require a post-it note with some deployment reminders on it, but it does seem like enough of an extra layer of hassle that might very well keep out all but the most clever and determined attackers. I’ve had to resign myself to "good-enough" security which isn’t perfect, but does let me get back to work after feeling alright about having given it the ol’ "College Try!"
1. Per my comment on June 15 here http://www.dotnetcurry.com/ShowArticle.aspx?ID=185 - let me know if I'm off-base! -and some more good commentary here Encrypting connection strings so other devs can't decrypt, but app still has access here Is encrypting web.config pointless? and here Encrypting web.config using Protected Configuration pointless?
2. Good discussion and food for thought on a different subject but very-related concepts here: Securely store a password in program code? - what really hit home is the Pidgin FAQ linked from the selected answer: If someone has your program, they can get to its secrets.
Is there a way to get a unique machine-specific system ID in a Flex application running in a browser, so that is can be used for example to determine if the machine is properly licensed to run the application?
I can't think of any way to do this based off the users machine or OS. The whole point of browser applications is to have them able to run anywhere, any time via a browser. To my knowledge Flash provides no information that could reasonable be converted into a unique machine ID for licensing purposes, not even the MAC address of a network card on the machine.
Personally, I think you'd be better off requiring a username/password for users to log in, and then using a session key stored in a cookie to allow the user to skip that step (e.g. a 'remember me on this computer' type of feature, such as GMail has). This has the advantage of the user being able to run the application from any PC they like.
Create a UUID inside flex
import mx.utils.UIDUtil;
var myUUID:string = UIDUtil.createUID();
I suppose if you want to get really clever you could encrypt this string with a locally known salt and generate some encrypted license key that can't be shared. You could change the salts or keys at regular intervals to enforce license expiration.
You will need to manage the key data on a backend somehow.
ILog Elixir does this, but they do it through a traditional install process. The swc files are watermarked, but when you enter your valid serial number unmarked swc files are unlocked and the source code is made available.
I don't have any details as to how they actually go about this, but it isn't directly through flex. Perhaps researching traditional software installation processes and unlocking encrypted data that way would produce the answer you are looking for.
You cannot really access machine specific information like MAC address or other ID's from a flex app. You should probably use some other technique like using ASP.NET or JSP.