Generating an X.509 certificate filled with raw data in Java - java

Basically, what I'm trying to achieve is making a private key/public certificate pair in order to export it to a pkcs12 repo. Certificate fields are to be populated with data that a user inserts through standard input or a GUI. This is a problem because I've only been able to find ways of loading an existing certificate and getting its v3 extensions, but not setting them. Additionaly, I would like to avoid using any external libraries such as BouncyCastle.
So far I've been able to produce a certificate using sun.security.tools.keytool.CertAndKeyGen class and X500Name object but I haven't found any method for feeding it an E-mail info since the X500Name doesn't have an appropriate constructor, as well as version 3 extensions (specifically basic constraints, alternative issuer name and key usage).
On the other hand, I have been looking into java.security.cert.CertificateFactory and its generateCertificate() method. It expects an InputStream of a base64 encoded existing certificate as an argument. So, to fullfill my requirements of generating a certificate and not loading an existing one, I've found a way of getting an InputStream from a String:
InputStream stream = new ByteArrayInputStream(exampleString.getBytes("UTF-8"));
I know that this string should begin with BEGIN CERTIFICATE and end with END CERTIFICATE to mimic an actual certificate but I don't know how to generate it from raw data.
So, to summarize my question: Is there a way to programatically populate an empty X.509 certificate with fields including e-mail and v3 extensions without using external libraries such as BouncyCastle?
Thanks in advance.

Related

Java & Windows-MY keystore - duplicated aliases

I'm implementing a mutual authentication with a web server in Java on Windows.
I have a certificate on a SmartCard which is supposed to be used to authenticate me (or other user).
So far I've figured out that I can access the certificates using Windows-MY key store.
I do it like that:
KeyStore keyStore = KeyStore.getInstance("Windows-MY");
keyStore.init(null, null);
This works. I can see all certificates inside keystoreSpi (in debugger). One of them is the one which I need to use - I confirmed that.
The problem is as follows:
KeyStore api allows me to get a certificate only by using it's alias. e.g. keyStore.getCertificate("alias") or keystore.getCertificateChain("alias")
I noticed that there are multiple different certificates with the same alias in this keystore. I cannot change the aliases. I just physicaly got the smartcard with given certificates.
When I call one of the mentioned methods, keystore returns just the first certificate in the list with given alias. (generally, in the implementation there is a map where aliases are it's keys, so all duplicated aliases are ignored).
Unfortunately first certificate's purpose is "email encryption", etc. The second certificate's purpose is "SmartCard Logon" and this one I need to use. I confirmed that by going into debugger and manually hacking the list of certificates.
The question is: how do I get a proper certificate using the API (eg. the second one) when there are duplicated aliases?
If this can be done by external libraries, I can opt for that.
More details which may be useful:
I use KeyStore, then create KeyStoreManager.
I initialize SSLContext with given keyStoreManager sslContext.init(keyManagerFactory.getKeyManagers(), ...)
I create HttpsUrlConnection with given ssl context, which is my objective.
This has been fixed a while ago. Just update to a recent JRE. For more information see here: https://bugs.java.com/bugdatabase/view_bug.do?bug_id=6483657

Keystore's password management

A keystore (no matter if it's used for "keystores" or "truststores") is initialized after creation using the load() method. One version expects an InputStream corresponding to the keystore file, and the password to decrypt the file. Providing the password to the method programmatically seems strange to me.
For example, a server uses a keystore to store its private keys and the associated certificates. The information present in the keystore is sensible so it is protected by a password. What are the problems of passing the password to the load() method programmatically? What is the best practice?
The other example, but for now concerning truststores. The client has a truststore where it stores the certificates of trusted CAs. As I understand it, the truststore doesn't contain the certificate of the server but only the certificates of the CAs that allow verifying the server's certificate. One truststore example I see is the one present with the JRE (in the security folder - cacerts). By looking at the configuration, I can see it is protected by the default password changeit. I understand that a truststore is implemented using a keystore, so it has (or maybe it's optional?) to be encrypted using a password. But, since truststores generally store public information (trusted CA's certificates) in the file, why changing the password is recommended?
Thanks
Providing the password to the method programmatically seems strange to
me.
I'm not sure why this would be strange. The application will need to be able to get hold of the content of the keystore at one point or another. The password will need to be passed to it, somehow. Passing it to the load() method doesn't make less sense than other solutions (avoid hard-coding, of course). Alternatively, you can use the method that uses a callback instead. If you don't think that's suitable, you can use a PKCS#11 provider and a hardware token (although you'll still need to enter the password/PIN somewhere) or use something like the Apple KeychainStore (where the password isn't used, but the OS keychain service takes care of that).
Regarding the truststore, there are in fact two passwords in use. They can be different, when using the JKS format. One protects the keystore itself, and one protects access to the private entries (getKey). In this case, the keystore password is used to prevent unauthorised parties from altering the truststore (and adding their own CA or server certificates).

JBoss/Java and SSL

Hi I'm a bit lost and hope you'll get me out of here. I'll try to be as clear as possible since I don't really understand/know how I should use certificates.
I've got an application that is supposed to communicate with another one using webservices and SSL. We both asked our main "Certificate Authority" to get certificates.
They sent us 4 files and a password for the .P12 file:
.csr, .cer, .key, .P12
Here is what I did :
* Configure JBoss to use SSL on 8443 and used the P12 file as the keystore
To test this I did a small Java class that call a webservices on this server, using :
props.setProperty("javax.net.ssl.trustStore", "/.../.../certif.p12");
props.setProperty("javax.net.ssl.trustStorePassword", "XXXXXXXXX");
props.setProperty("javax.net.ssl.trustStoreType", "PKCS12");
The connection works, but I think I'm missing something as I did not use the other files.
If I send my .P12 file and the password to the application that is supposed to call my Webservices will it be ok/enough ?
Edit :
I forgot to mention that I should call a Webservice on the other application too, so it should be the other way around, do I only need a .P12 and pass ?
I've read a lot of thing about public key, private key, keytool but it's a bit messy in my head right now.
Thanks for any information !
They sent us 4 files and a password for the .P12 file: .csr, .cer,
.key, .P12
Ideally, you should have generated the private key (in .key) and CSR (in .csr) yourself and the CA should have come back with the certificate (typically in .cer) based on the CSR, which you would have assembled together to build your PKCS#12 file (.p12).
At this stage, you can discard the CSR. The PKCS#12 file should now contain the private key, its associated certificate and possibly the certificate chain attached. You could extract the .key and .cer files from that .p12 file later again. I guess you were given all these files because of the way they have been generated (using intermediate files), or for convenience, not to have to convert them yourself.
The Java terminology isn't ideal, but keystore and truststore are two entities of type keystore, but with a different purpose. The difference between the KeyManager and TrustManager (and thus between javax.net.ssl.keyStore and javax.net.ssl.trustStore) is as follows (quoted from the JSSE ref guide):
TrustManager: Determines whether the remote authentication credentials (and thus the connection) should be trusted.
KeyManager: Determines which authentication credentials to send to the remote host.
The javax.net.ssl.trustStore* properties are one way of configuring the TrustManager. The javax.net.ssl.keyStore* properties are one way of configuring the KeyManager.
Typically, there is no need for private key material in a trust store (unless you also use the same as a keystore). It's often better to use a separate truststore, which you'd be able to copy freely across machine, without worrying about leaking private key material.
What would make sense would be to build a new keystore (JKS) that you would use as a truststore, using the CA certificates (not sure if you've been provided with them).
You're not doing mutual authentication by setting the truststore only (there are no default values for the keystore, so they need to specify these parameters explicitly). If you want to use your client-certificate to connect to a remote party, you need to set it in the keystore (for example, using the javax.net.ssl.keyStore* properties in the same way you've done it for the trust store).
You could point both the keystore and truststore to the same .p12 file. The side effect is that other connections made by your service to other places (e.g https://www.google.com) would not be trusted, since it wouldn't contain the CA for those. That's why it might be better to create a separate "truststore keystore" (JKS might be easier) for the CA certificates. You could make a copy of the default cacerts (in the JRE directory), import your CA's certificate into it and use that.
I've got an application that is supposed to communicate with another
one using webservices and SSL.
Ok, stop here. Communicate how? I mean is it only server authentication i.e. your client application will authenticate the web service or mutual authentication and the web service will also request your applications certificate?
This is important as the files you present by the names seem to suggest the latter i.e. that mutual authentication is expected while your code you show is only setting SSL library for server authentication.
Since you are not providing context here I would say that:
.key has your private key
.p12 has your private key along with your signed certificate or perhaps the CA's root certificate (?)
cer could have your signed certificate or perhaps the root's CA
signing certificate that is considered as trusted in the domain and
has probably also signed the web service you want to communicate with
certificate (well that is a possibility/guess here since you don't
say much)
csr is your certificate signing request
I did a small Java class that call a webservices on this server, using
What you do in the code is setting the p12 as the truststore.
If you say this works then there is no mutual authentication only server side authentication and you are authenticating the web service using whatever is in the p12.
In this case the rest are not needed for communication.It is for you to keep especially the key file since this could be your private key and if you lose/someone steals this then your private certificate is useless/compromised.
I am not sure what your requirements on security are here, but it seems to me that you should probably look into it more.
Even for this question I just tried to do an educated guess based on the file names.....
I hope this puts you in some track to read.

TLS/SSL client authentication using a client certificate which comes available at runtime Android/Java

Suppose I have an application which in some way retrieves a client certificate (private/public key pair) at runtime via a secure channel (so I don't have this client certificate at build time).
How can I use this client certificate for client authentication without using keytool and not using some on persistent/ondisk keystore. So I do not want (actually I can't) to import it using a command line keytool?
Actually I want to replicate the functionality done in libcurl. You just set the client certificate (with private key) and your done. It doesn't involve a keystore.
All this has to be done in Java/Android.
You can do it in Java by defining your own KeyManager as described in the JSSE Reference Guide. I can't speak for Android.
I just got this working and I dont think you'll be very happy with my answer but it does work :)
So the hard part is to get the pkcs12 certificate you need to perform client authentication, if your certificate is already in pkcs12 then you've got all the hard stuff out of the way and you can refer to the second answer on SSL client authentication in Android to see how to use that certificate.
if you just have a public private key pair and not a pkcs12 certificate then you will need to make one. As far as I could tell there is no way in java/android to create this certificate so you need to use the android NDK and openssl.
if you download the openssl-android project from https://github.com/guardianproject/openssl-android you can use it to build openssl. By default it compiles as a .so shared object but only some of the android devices I tried to run this code on were able to link against libcrypto, so, although im sure there is a better way I went into the Android.mk files and replaced include $(BUILD_SHARED_LIBRARY) with include $(BUILD_STATIC_LIBRARY) in a few places so that I could compile a .a static library.
I then used the info from Android NDK: Link using a pre-compiled static library to link the libcrypto.a I compiled to my native code.
This native code uses openssl to first create an X509 certificate and then uses it to create a PKCS12 file which can be used in the manner I mentioned before located at SSL client authentication in Android
first you need to get your public and private keys into native land as EVP_PKEY pointers which can happen in a variety of ways based on what format your keys are in then you can use the following code to create an X509 certificate
X509 *public_key_cert = X509_new();
X509_gmtime_adj(X509_get_notBefore(public_key_cert),0);
X509_gmtime_adj(X509_get_notAfter(public_key_cert), (long) 60*60*24*365);
X509_set_pubkey(public_key_cert,evp_pub_key);
This creates the most minimally valid X509 certificate which is valid for 1 year. You may want to do other stuff like sign the certificate if you are going to run your own certificate authority, or set any of a large set of headers which contain various bits of information.
next you need to create the pkcs12 certificate using the X509 cert like this:
PKCS12 *pkcs12 = PKCS12_create(password, "Some Sort of Friendly Name", evp_priv_key, public_key_cert, NULL, 0, 0, 0, 0, 0);
password is a char* containing the password which will be used to encrypt the private key using triple-DES
Now that you have a pkcs12 certificate you can go over to SSL client authentication in Android and get client authentication going.
Good Luck!

Adding certificates used by URL.openStream

I have some code on Android that makes use of URL.openStream. For internal test purposes I need to be able to point it to a server that uses a private CA. We already have our CA bundles in PEM format (as we're also using libcurl from NDK), and would like to be able to just read the PEM files directly into whatever KeyStore (or similar) that URL.openStream uses.
So this question is a multi-part thing:
How do you get the key storage used by URL.openStream? Or should I just be using HttpClient directly?
How do you add a PEM certificate to said key storage? (even if using HttpClient)
Thanks.
I can't speak for Android specifically, but at least standard desktop Java has a default keystore that is used by all instances of the JVM, located at /lib/security/cacerts.
In many cases, this file should not be modified globally for all instances of the JVM, but on a case-by-case basis, as you already eluded to. To do this, you can't call .openStream directly. Instead, get a HttpsURLConnnection by calling URLConnection.openConnection() (and casting it do a HttpsURLConnection). Before performing any other operations on this connection, set a custom SSLSocketFactory by calling HttpsURLConnection.setSSLSocketFactory. From here, you'll need to work with a custom SSLContext and TrustManagers.
Some additional details around this are already answered at How can I use different certificates on specific connections?.
If you want to use HttpClient, additional references are available at http://hc.apache.org/httpclient-3.x/sslguide.html and How to handle invalid SSL certificates with Apache HttpClient?.

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