iOS上的RSA加密（RSA / ECB / PKCS1Padding）

Question

I need to encrypt a NSString using a public key from a webserver certificate on iOS. This is what I am doing on Android (works fine):

public byte[] Encrypt(String plain) throws NoSuchAlgorithmException,
            NoSuchPaddingException, InvalidKeyException,
            IllegalBlockSizeException, BadPaddingException {

        publicKey = "MyPublicKeyStringExtractedFromACertificate"

        cipher = Cipher.getInstance("RSA/ECB/PKCS1Padding");
        cipher.init(Cipher.ENCRYPT_MODE, publicKey);
        encryptedBytes = cipher.doFinal(plain.getBytes());

        return encryptedBytes;
}

This is what I am trying on iOS:

NSString *publicKey = @"MyPublicKeyStringExtractedFromACertificate"; // Base64 encoded key from my webserver certificate
NSData *keyData = [[NSData alloc] initWithBase64EncodedString:publicKey options:NSDataBase64DecodingIgnoreUnknownCharacters];
SecCertificateRef certificate = SecCertificateCreateWithData(kCFAllocatorDefault, ( __bridge CFDataRef) keyData); // this is returning nil

The publickey comes from a webservice certificate (on my app bundle).

What I am doing wrong? How could i use SecKeyEncrypt?

Answer 1

MIHCrypto has everything i need. https://github.com/hohl/MIHCrypto

Answer 2

You can't encrypt with Java Cipher using a string as the public key. You need a PublicKey object. For example:

X509EncodedKeySpec publicSpec = new X509EncodedKeySpec(der_bytes);
KeyFactory keyFactory = KeyFactory.getInstance("RSA");
PublicKey publicKey = keyFactory.generatePublic(publicSpec);

der_bytes needs to be in DER form, not PEM form, here.