Load a RSA private key in Java (algid parse error, not a sequence)

encryption, java, openssl, rsa

Solution

You could still load the keys if necessary,

public static PublicKey bigIntegerToPublicKey(BigInteger e, BigInteger m)  {
    RSAPublicKeySpec keySpec = new RSAPublicKeySpec(m, e);
    KeyFactory fact = KeyFactory.getInstance("RSA");
    PublicKey pubKey = fact.generatePublic(keySpec);
    return pubKey;
}

public static PrivateKey bigIntegerToPrivateKey(BigInteger e, BigInteger m) {
    RSAPrivateKeySpec keySpec = new RSAPrivateKeySpec(m, e);
    KeyFactory fact = KeyFactory.getInstance("RSA");
    PrivateKey privKey = fact.generatePrivate(keySpec);
    return privKey;
}

all you need is the modulus and the exponent.

Problem

I'm trying to load a private RSA key generated with ssl into java, my code is: Generate the key: ``` openssl genrsa -out mykey.pem 1024 ``` Result: ``` -----BEGIN RSA PRIVATE KEY----- MIICXAIBAAKBgQCUibP4fY2PA/sGMKMbU6usuIGcOAqgQjD6c2ylVo05Oz7pgjnE +O0l2MFRUYUGT5KKk/W+0cAXkxaQHE3n8A8X1mHT8eMDmWnzz0PeYjDE8LQmAw8R Y2FnVKFAB36BIjdb5FsZmCk5QYKU5+nWLMqH/j/IR5AyX5wR2SMoslUg2QIDAQAB AoGAeJ1s7638IhLIZtldyRXjRKi6ToFPV50IKodJxOSIXt3WE0V05ZaA84eUSxUY IOzCgRbuqVmnUz1USAdD18AecC8qc7tXTRALLy7q8fxklPwmGPUOvTFmI7gRMUnv cWrq1gySk3SKpj0YmWnuY9Xmd2+xoWLzUeFD1CROY5OTjIECQQDDlp1+Al7+duR0 XyMlkWLIk0nIbkQ5zlTAEipzmaeTSOJi6YG3EMMz3AGuZb7tw6HFxWqeg1hyKJ+T cTM3WTdJAkEAwmrCDKE29n3wFOBKsZZFQbDgVOUXCBs2ubEI+ALe1DJU5BlfnrhJ OINRCNgnwSFNbwxDTkDpR6J6Av2ElAvNEQJAV0dVvk5Wj50Ecz2lFHWdLD41taAn B9igDxnMIcvWcK4cf+ENhmCPiwvJIEa8/aLIBNYErvmTtVWVaBkirrc8KQJABr+z +sJB6S6X/fGHRkDkKJKeRvQo54QiUzHdENbwq0cQAVcMJbNZ/1c3oen2/1JLoNY5 I+dG8dCnEaGBT65VMQJBAIDqH1Kqs5tb51cpt6h9ot31SUVud5pSML/babwp3pRs 1s6poreym4PkAyRug0Dgcj1zVLt25TlOHvrL9r3Swq8= -----END RSA PRIVATE KEY----- ``` Load: ``` String privKeyPEM=readFile("mykey.pem"); privKeyPEM= privKeyPEM.replace("-----BEGIN RSA PRIVATE KEY-----", "").replace("\n", ""); // Remove the first and last lines privKeyPEM = privKeyPEM.replace("-----END RSA PRIVATE KEY-----", ""); System.out.println(privKeyPEM); // Base64 decode the data byte [] encoded = Base64.decode(privKeyPEM); // PKCS8 decode the encoded RSA private key PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(encoded); KeyFactory kf = KeyFactory.getInstance("RSA"); PrivateKey privKey = kf.generatePrivate(keySpec); // Display the results System.out.println(privKey); ``` and it throws an `IOException : algid parse error, not a sequence`. Where is the error? ``` Exception in thread "main" java.security.spec.InvalidKeySpecException: java.security.InvalidKeyException: IOException : algid parse error, not a sequence at sun.security.rsa.RSAKeyFactory.engineGeneratePrivate(Unknown Source) at java.security.KeyFactory.generatePrivate(Unknown Source) at base54.encrypt.RSAToy.main(RSAToy.java:36) Caused by: java.security.InvalidKeyException: IOException : algid parse error, not a sequence at sun.security.pkcs.PKCS8Key.decode(Unknown Source) at sun.security.pkcs.PKCS8Key.decode(Unknown Source) at sun.security.rsa.RSAPrivateCrtKeyImpl.<init>(Unknown Source) at sun.security.rsa.RSAPrivateCrtKeyImpl.newKey(Unknown Source) at sun.security.rsa.RSAKeyFactory.generatePrivate(Unknown Source) ```

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