Blowfish encryption in android

Question

cipher = Cipher.getInstance("Blowfish");

This throws an exception java.security.NoSuchAlgorithmException: Cipher Blowfish implementation not found.

I checked both local_policy.jar and US_export_policy.jar exist and they weren't changed from the moment of java installation. What can cause this problem?

Edit:

Object[] o = Security.getAlgorithms("Cipher").toArray();
    for (int i=0; i<o.length; i++) {
        System.out.println((String)o[i]);
    }

When I run this code I get list without "Blowfish" but among algorithm names such as DES or RSA there are some unknown names such as "1.2.840.113549.1.1.7" and like that. Why there's no Blowfish there or is it hidden in those numbers?

Wisniewski

Answer 1

Yeap, I couldn't find the solution and just used the GNU crypto library. It works fine.

Wisniewski

Answer 2

cipher = Cipher.getInstance("Blowfish")

only works with Android 2.3 and higher, so it may be that your target is below Android 2.3?

EDIT: If you want to build to 2.3 or let's say 4.0 ICS but also support lower devices you can add something like this to your Manifest.xml:

<uses-sdk android:minSdkVersion="3" />
<uses-sdk android:targetSdkVersion="14" />

The only problem is you would have to offer Blowfish as an option that would not be a valid choice (unclickable/greyed out) of an encryption method for anyone under 2.3, I'd assume. Test it! Build it, and try it on a variety of SDK versions. Good Luck!

Pentaprism

I use Android 2.1, then how can I use Blowfish in Android 2.1? – Wisniewski

Unfortunately, you cannot. But, you could always target 2.3 but allow lower SDK versions like this. I will post the code in an edit above as a solution. – Pentaprism

that's the problem, I need 2.1 platform – Wisniewski

encrypt and decrypt, I assume? – Pentaprism

groups.google.com/d/msg/android-developers/pDSjk6FI9dM/… and mail-archive.com/[email protected]/… may help as alternatives, then. – Pentaprism

Also, @Wisniewski have you tried to build it with the target 2.3 or above and 2.1 as a minSDK? I think it is absolutely worth a shot. It may work! – Pentaprism

this is strange, even for android 4.0 it's the same exception – Wisniewski

Answer 3

The only solution I can suggest is to an external package if you want complete platform support.

Android comes with a stripped out version of BouncyCastle. Which I believe is having additional functions added as the versions progress.

However, importing the complete BouncyCastle jar into android causes a great many issues as the Android version uses the same names.

The solution I have used is to use SpongyCastle. I have made use of it before, but have not looked through the source code to ensure no changes have been made.

A guide to installing: How to include the Spongy Castle JAR in Android?

Gabbro

Answer 4

local_policy.jar and US_export_policy.jar are not relevant to Android. You need to run your algorithm listing code on Android to get a meaningful result. As others have noted, the Android JCE provider is based on Bouncy Castle, but it does not include all algorithms. You need to bundle the full lib in your app to be able to use all algorithms. Do use Spongy Castle to make this easier. After you do, the only change you will need is to specify the provider as 'SC':

Cipher c = Cipher.getInstance("Blowfish", "SC");

Illusionism

Answer 5

I used blowfish encryption on my android application. I don't know why but the blowfish encryption has been commented out of the bouncy castle library on android.

I had to download the bouncy castle sources, I changed the provider name from BC to BC2 and renamed the package name into bouncycastle2 to avoid a conflict with the one already on the android sdk . Then I added this custom Bouncy Castle jar into my application as a new jar and it works fine !

Ventre