Store RSA keys

[mgarbayo]

Hi,
I´m working on SMS encryption.
I´ve got S60 3rd edition SDK.
I´m using RSA algorithm provided at Symbian Criptography Library. I can encrypt and decrypt but i can´t store de keys that i generate.
First, i tried to write the KeyPair object to a file, redefining the ExternalizeL and InternalizeL methods, but these methods only work when you try to write pre-defined types (such as integer, booleans, descriptors...), and the types I want to store are CRSAPrivateKey and CRSAPublicKey.
Then I found the The unified key store, but it won´t work with my SDK (only works with S60 UIQ).
At least, i tried to write the parameters that create the keys, but It is impossible to obtain the D parameter from de Private Key.
Any idea?
Thank you so much.

[wizard_hu_]

Have you seen http://wiki.forum.nokia.com/index.php/Asymmetric_crypto ?

[bernisheart]

Have you seen http://wiki.forum.nokia.com/index.php/Asymmetric_crypto ?

Yes, but using S60 3rdEdition, you can't include <x509keys.h>.
Also, there are no explanations about how to work and store the private key.
Someone knows where to find more useful information, or any example about how to store in memory the keys?
Thanx

[rbox]

Hi
I have the same problem. Have any resolve this problem.
How to export public key and private key in S60 3rd MR.
Thanks in advance.

[wizard_hu_]

TInteger and RInteger seem to be the relevant classes, and there are TInteger::BufferLC and RInteger::NewL apparently suitable for storing-restoring.

[rbox]

TInteger and RInteger seem to be the relevant classes, and there are TInteger::BufferLC and RInteger::NewL apparently suitable for storing-restoring.

I know that, but how to get the D parameter from the private Key.
This is my problem.

Maybe there is diffrent way to export private and public key. Any suggestion?

[Paul.Todd]

Unfortunatly the API's you require are not in the public SDK, you need to be a Symbian partner to use and obtain them.

There is more information and examples on working with certificates here, and though its UIQ documentation it works with S60 as well.

http://developer.uiq.com/devlib/uiq_....creatingStore

[MobiSecLap]

RSA without sending keys or getting it become with no benfits and what the solution to interest from RSA in symbian.(i generate keys and encrypt and decrypt in the same machine and in the same time and after close program i can't decrypt encrypted message)

[wizard_hu_]

Note that the restriction is about the private key, which is not required for encryption. The use case is that you generate the keys, send the public key to anyone, then the message can be encrypted using the public key, but only you will be able to decrypt it.

[MobiSecLap]

Note that the restriction is about the private key, which is not required for encryption. The use case is that you generate the keys, send the public key to anyone, then the message can be encrypted using the public key, but only you will be able to decrypt it.

yes but private required for decryption so i need to store and i will try the snippet code u give me in the another thread and if this correct and generation of keys with e,n are the same the problem solved

[vaibhavjain]

May be I have understood your question incorrectly. But you can only get the D parameter of an rsa key pair if you have generated the key pair with EStandard flag CRSAKeyPair::NewL(2048,EStandard); . Default is EStandardCRT that uses chinese remainder theorm to speed up computations. D parameter if only valid for standard keys.

If you have standard key then you can cast the PrivateKey() output to CRSAPrivateKeyStandard & to get the D parameter in way similar to code below:

const RInteger & d= ((CRSAPrivateKeyStandard &)generator->PrivateKey()).D();

Once you have the RInteger you can simply store it to a file or any place you need by simply using the RInteger::BufferLC() method.

Hope that helps,
VJ