Hello , Sorry my code is working very well, i didn't see i was using again the public key to decrypt. it's working only with RSA/ECB.PKCS1 , not with RSA/NONE/PKCS11. Now we wil make the authentication with our Tomcat server , during this phase some messages sended by the server are more than 128 bytes, i think i will use RSA to send a 3DES key in order to crypt the message, or i have too a 64 ko card that support the RSA 2048, so i don't really need to use the 3DES if i just want to crypt a message of about 150 bytes, what do you think thanks kind regards , Franck
Michael StJohns-2 wrote: > > > Sorry - I forgot that from your original posts. > > I do suggest exporting the private key and doing a manual decrypt to find > out how the card encrypts the data. > > byte[] ciphertext (after the card encrypts your data) > byte[] privateModulus > byte[] privateExponent > > BigInteger cipherBig = new BigInteger (1, ciphertext); > BigInteger modBig = new BigInteger (1, privateModulus); > BigInteger expBig = new BigInteger (1, privateExponent); > > BigInteger plaintextBig = cipherBig.modpow(expBig, modBig); > > The last 4 octets of plaintextBig.toByteArray() should be your 01 02 03 04 > bytes. The rest should be the padding. > > Mike > > > At 12:27 PM 5/1/2009, jose85 wrote: > >>No my initial text was only 4 bytes array, like in the first post, >>but once it is crypted by the card the length is 128 bytes . >> >> >>OK - I think I see one more possibility for the problem. If you're using >>padding, then the plain text MUST be shorter than the key length to allow >>for the addition of padding. Reduce the cipher text by 20 octets and try >>again. >> >>Mike >> >> >>-- >>View this message in context: http://www.nabble.com/Export-RSA-public-key-out-of-the-card-tp23239829p23335864.html >>Sent from the MuscleCard mailing list archive at Nabble.com. >> >>_______________________________________________ >>Muscle mailing list >>[email protected] >>http://lists.drizzle.com/mailman/listinfo/muscle > > > _______________________________________________ > Muscle mailing list > [email protected] > http://lists.drizzle.com/mailman/listinfo/muscle > > -- View this message in context: http://www.nabble.com/Export-RSA-public-key-out-of-the-card-tp23239829p23385523.html Sent from the MuscleCard mailing list archive at Nabble.com. _______________________________________________ Muscle mailing list [email protected] http://lists.drizzle.com/mailman/listinfo/muscle
