RSA/ECB/PKCS1Padding

[chandrakant-kshirsagar]

@whyoleg How to use the below code here.

Cipher cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");

[whyoleg]

Hey! Sorry, but RSA with PKCS1 encryption is not yet supported. Only RSA OAEP is supported for now.

Could you please describe why do you need this specific algorithm? Is it needed to community with some old software? I'm asking this, because generally, RSA with PKCS1 encryption is not supposed to be used for new applications, so that's why I delayed adding it, providing more robust algorithms first.

[chandrakant-kshirsagar]

@whyoleg thanks for the information.

Currently, I am converting my old code to compose-multiplatform, which uses RSA/ECB/PKCS1Padding encryption. Should I migrate my code to RSA OAEP or is there any further plan for RSA with PKCS1?

[whyoleg]

Yeah, if you control server part and so could use RSA OAEP for your use case - then it's better to do it. RSA with PKCS1 encryption probable will be supported in upcoming release, but there is no date yet - may be in a couple of months - hard to predict my workload right now.

[chandrakant-kshirsagar]

@whyoleg I will discuss with my backend team about changing the encryption to RSA OAEP. Thank you for your support.👍

[e9ab98e991ab]

import java.security.KeyFactory import java.security.spec.X509EncodedKeySpec import android.util.Base64 import javax.crypto.Cipher

actual object RSAUtils {
    actual fun encryptData(str: String, key: String): String { 
        val keyBytes = Base64.decode(key,Base64.NO_WRAP)
        val pubKeySpec = X509EncodedKeySpec(keyBytes)
        val keyFactory = KeyFactory.getInstance("RSA")
        val pubKey = keyFactory.generatePublic(pubKeySpec)
 
        val cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding")
        cipher.init(Cipher.ENCRYPT_MODE, pubKey)
        val encryptedBytes = cipher.doFinal(str.toByteArray())
        // NO_WRAP 表示不在结果中加上换行和空格
        return URLEncoder.encode(Base64.encodeToString(encryptedBytes,Base64.NO_WRAP), "UTF-8")
    }
}

Android is implemented in KMM. I don't know how to write iOS. The hard author wrote the code of iOS and merged into the library

[ivanpataki]

Hi, Plus one here, unfortunately I cannot change the server side encryption, so looking forward to 0.4.0! Thanks!

[jvondermarck]

I would also have the use case to use AES ECB encryption for an old app that cannot be migrated to a safer encryption. So it would be great in the future to implement it.

[whyoleg]

AES.ECB, RSA.RAW (jdk: RSA/ECB/NoPadding) and RSA.PKCS1 encryption (RSA/ECB/PKCS1Padding) are available in main branch and so in 0.4.0 snapshots. No date for release yet as I need to finish other things. API is a bit clattered for those legacy RSA algorithms (e.g digest is required, but is not used). It will be definitely changed before 1.0 someday.

[whyoleg]

0.4.0 was just released! RSA encryption with PKCS1 padding and without padding are available now.