我正在尝试使用模数和指数为RSA生成公钥的应用程序。但是,有一个问题,模数和指数都可能是十六进制值。这是我用于生成密钥的代码,标记为 - <的行是错误发生的位置。错误:RSA密钥长度必须至少为512位?
RSAPublicKeySpec spec = new RSAPublicKeySpec(new BigInteger(1,hexToByte(rsaJSON.publickey_exp)),new BigInteger(1,hexToByte(rsaJSON.publickey_mod)));
KeyFactory factory = KeyFactory.getInstance("RSA");
PublicKey pub = factory.generatePublic(spec); <---
Cipher cipher = cipher = Cipher.getInstance("RSA/None/OAEPWithSHA1AndMGF1Padding", "BC");
cipher.init(Cipher.ENCRYPT_MODE, pub);
.....
String HEXES = "ABCDEF";
public static String byteToHex(byte [] raw) {
if (raw == null) {
return null;
}
final StringBuilder hex = new StringBuilder(2 * raw.length);
for (final byte b : raw) {
hex.append(HEXES.charAt((b & 0xF0) >> 4))
.append(HEXES.charAt((b & 0x0F)));
}
return hex.toString();
}
public static byte[] hexToByte(String hexString){
int len = hexString.length();
byte[] ba = new byte[len/2];
for (int i = 0; i < len; i += 2) {
ba[i/2] = (byte) ((Character.digit(hexString.charAt(i), 16) << 4) + Character.digit(hexString.charAt(i+1), 16));
}
return ba;
}
一个例子模数和指数将被投入这如下:
modulus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
exponent:"010001"
堆栈跟踪,在大多数情况下:
java.security.spec.InvalidKeySpecException: java.security.InvalidKeyException: RSA keys must be at least 512 bits long
at sun.security.rsa.RSAKeyFactory.engineGeneratePublic(Unknown Source)
at java.security.KeyFactory.generatePublic(Unknown Source)
.....
我不会假装我知道为什么这个错误发生,因为我的知识才智h RSA加密是有限的。如果有人能帮我弄清楚为什么这个错误会持续出现,那将非常有帮助:)
非常感谢!我扭转了这些论点,并按照你说的方式进行了转换,它的工作:) – VoidWhisperer