private IRubyObject setKeySpecComponent(int index, IRubyObject value) {
BigInteger[] vals;
// illegal to set if we already have a key for this component
// FIXME: allow changes after keys are created? MRI doesn't prevent it...
if (this.pubKey != null
|| this.privKey != null
|| (vals = this.specValues) != null && vals[index] != null) {
throw newDSAError(getRuntime(), "illegal modification");
}
// get the BigInteger value
BigInteger bival = BN.getBigInteger(value);
if (vals != null) {
// we already have some vals stored, store this one, too
vals[index] = bival;
// check to see if we have all values yet
for (int i = vals.length; --i >= 0; ) {
if (vals[i] == null) {
// still missing components, return
return value;
}
}
// we now have all components. create the key.
DSAPublicKeySpec spec =
new DSAPublicKeySpec(vals[SPEC_Y], vals[SPEC_P], vals[SPEC_Q], vals[SPEC_G]);
try {
this.pubKey = (DSAPublicKey) KeyFactory.getInstance("DSA").generatePublic(spec);
} catch (InvalidKeySpecException e) {
throw newDSAError(getRuntime(), "invalid keyspec");
} catch (NoSuchAlgorithmException e) {
throw newDSAError(getRuntime(), "unsupported key algorithm (DSA)");
}
// clear out the specValues
this.specValues = null;
} else {
// first value received, save
this.specValues = new BigInteger[4];
this.specValues[index] = bival;
}
return value;
}
