Scala - Illegal base64 character 5c-CodePudding

I have a base64 string like this:

MIIEpAIBAAKCAQEAtp/Uo28kOjROL50aajnpK25CJoVoic2bqqu6OS2baWWD9fT2\nESqq8mbFxYN3O7JXbs 74YpTdg1jSUALOz9zj/H2eCF71QYvoHmdoi0iiQuy3gS1\n6YczVvBvinSwfEnO6Wi/Xx6AC8urdreUR0c 5cNNSqI9oyrwA4m/XrFwR6ptT9oy\nyahrVJdjA2Wdf O4/0lW jrMw s\nQptfu4QslKhDnRUFu4ALqm3nypD/ojGjFCEl5poiBMMztqIpE7f9t IBY/zJbOBP\nI sHVgwH/pJbi0CqIiDNIEiXsLDERTldzvA4DQIDAQABAoIBAFu IVlVLRLcUebT\neoCgxQUfZ7XoUSLhGnF7wZqV0bv51ngJ7k jaqtJe9MEfzKLHic5zn24OsNUaGtU\n9A94ibpnaFTjJU1XxTdNwSXGnNHSAbJNFYHSfLURJkec5Uga4Aobp//F17eVQnbq\nNGA2Z1 PZFW4 VPt7xMn8O5GH0ywdFhj4PI z UT0j1ezebjzDM2FoKwjfvA0wHg\nbZuyFjb0EBNsaW9y1quh2sSaHAFATYoTLG3ArM/Ue4Fr/Qom0/5N3uusifMdWEcA\nw7/yiI9D7Q4XsqoZ9gqAhXOcWgJmjvsx66zqUbArw/HmqIy5/vQfoZV78ux2iyZP\nO9n68AECgYEA6GP5Ns8Zfgm9Y7J5OxjgGwwQYZziKGysnYIe2N6y9jbjXdjsTtTH\nJKeeM eHL3Mq2yrYj9m3bACE/uNQ/4o V hvVQusN bMpY5YGHm4KiGL0ieNYs3B\nA6LLGni7itMY5SC9g7Rm5tlAvUmv38NTKcS47Wz1YKrnhId4x5eWPAECgYEAyS2J\nB8/6 C3jowJWJoguLKWWeEF5sPe9IWTqWxoUuJRLaSoKTWl0VKPB60DZZEpbPh2n\nuQlfaRnbt/YZBIeBqnrZzqiO5iTDDtw8zOa0B DLv9OX9I4dzbQ PtH/CRH6cDst\nhrMUUqW5K56za gH8iiyvBAxjJG11QctUdIh0GZdgdhkW2YFYO\nClWYyCaqhfWOeJOjtQNgBGleXRF/4EJRNJP8wTuXVK Vnrynq6dk2tyb77TyLRTZ\nF5ZsrQKBgQCaNIpP1tGYpYTfFny5xQ8aY5e6Bd3/aC5Ays8wYb8oAPYwH9AeqWY2\nsistzq9ARRbvwXzl45HzRKYoWVd1D0D5yOwxFOW  VD3luXH1UpEB1bvxHrpIwbD\ngg9jhO9K1yri6JGA5ENx5InrvKsqodP/llszVJysBlUeAcwMo2gjNA==

Please note that above string is private key so some characters have been purposely removed.

And I am trying to convert it in bytes:

def convertToBase64(privateKeyB64: String) = {
    val bytesArray = java.util.Base64.getDecoder.decode(privateKeyB64.replaceAll("\\r\\n|\\r|\\n", ""))
    import java.security.KeyFactory
    import java.security.spec.PKCS8EncodedKeySpec
    val spec = new PKCS8EncodedKeySpec(bytesArray)
    // create key form spec
    val keyFactory = KeyFactory.getInstance("RSA")
    keyFactory.generatePrivate(spec)

  }

The above code fails at the step: val bytesArray = java.util.Base64.getDecoder.decode(privateKeyB64.replaceAll("\\r\\n|\\r|\\n", "")) with the error:

Exception in thread "main" java.lang.IllegalArgumentException: Illegal base64 character 5c

I am not sure what is it complaining about exactly? What does 5c mean in base64?

CodePudding user response：

Perhaps you should double check the encoding of your Base64 data. Base64 data can come encoded in different formats as defined in RFC 4648 and RFC 2045. Java has different implementations for three different types of encoding as documented in the java.util.Base64 JavaDoc, Basic, MIME and URL-safe. From a couple of experiments it looks like yours is in the MIME format, so the following should work:

def convertToBase64(privateKeyB64: String) = {
  val bytesArray = java.util.Base64.getMimeDecoder.decode(privateKeyB64)
  val spec = new java.security.spec.PKCS8EncodedKeySpec(bytesArray)
  java.security.KeyFactory.getInstance("RSA").generatePrivate(spec)
}

I tried to run it locally but now the problem shifts towards generating the private key, so there may be some mismatch between the key you are generating and the expected format. Perhaps it's not a valid PKCS#8?