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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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package sun.security.ssl;
import java.io.*;
import java.security.*;
import javax.crypto.*;
import javax.net.ssl.*;
import sun.security.internal.spec.TlsRsaPremasterSecretParameterSpec;
import sun.security.util.KeyUtil;
/**
* This is the client key exchange message (CLIENT --> SERVER) used with
* all RSA key exchanges; it holds the RSA-encrypted pre-master secret.
*
* The message is encrypted using PKCS #1 block type 02 encryption with the
* server's public key. The padding and resulting message size is a function
* of this server's public key modulus size, but the pre-master secret is
* always exactly 48 bytes.
*
*/
final class RSAClientKeyExchange extends HandshakeMessage {
/*
* The following field values were encrypted with the server's public
* key (or temp key from server key exchange msg) and are presented
* here in DECRYPTED form.
*/
private ProtocolVersion protocolVersion; // preMaster [0,1]
SecretKey preMaster;
private byte[] encrypted; // same size as public modulus
/*
* Client randomly creates a pre-master secret and encrypts it
* using the server's RSA public key; only the server can decrypt
* it, using its RSA private key. Result is the same size as the
* server's public key, and uses PKCS #1 block format 02.
*/
@SuppressWarnings("deprecation")
RSAClientKeyExchange(ProtocolVersion protocolVersion,
ProtocolVersion maxVersion,
SecureRandom generator, PublicKey publicKey) throws IOException {
if (publicKey.getAlgorithm().equals("RSA") == false) {
throw new SSLKeyException("Public key not of type RSA: " +
publicKey.getAlgorithm());
}
this.protocolVersion = protocolVersion;
try {
String s = protocolVersion.useTLS12PlusSpec() ?
"SunTls12RsaPremasterSecret" : "SunTlsRsaPremasterSecret";
KeyGenerator kg = JsseJce.getKeyGenerator(s);
kg.init(new TlsRsaPremasterSecretParameterSpec(
maxVersion.v, protocolVersion.v), generator);
preMaster = kg.generateKey();
Cipher cipher = JsseJce.getCipher(JsseJce.CIPHER_RSA_PKCS1);
cipher.init(Cipher.WRAP_MODE, publicKey, generator);
encrypted = cipher.wrap(preMaster);
} catch (GeneralSecurityException e) {
throw (SSLKeyException)new SSLKeyException
("RSA premaster secret error").initCause(e);
}
}
/*
* Retrieving the cipher's provider name for the debug purposes
* can throw an exception by itself.
*/
private static String safeProviderName(Cipher cipher) {
try {
return cipher.getProvider().toString();
} catch (Exception e) {
if (debug != null && Debug.isOn("handshake")) {
System.out.println("Retrieving The Cipher provider name" +
" caused exception " + e.getMessage());
}
}
try {
return cipher.toString() + " (provider name not available)";
} catch (Exception e) {
if (debug != null && Debug.isOn("handshake")) {
System.out.println("Retrieving The Cipher name" +
" caused exception " + e.getMessage());
}
}
return "(cipher/provider names not available)";
}
/*
* Server gets the PKCS #1 (block format 02) data, decrypts
* it with its private key.
*/
@SuppressWarnings("deprecation")
RSAClientKeyExchange(ProtocolVersion currentVersion,
ProtocolVersion maxVersion,
SecureRandom generator, HandshakeInStream input,
int messageSize, PrivateKey privateKey) throws IOException {
if (privateKey.getAlgorithm().equals("RSA") == false) {
throw new SSLKeyException("Private key not of type RSA: " +
privateKey.getAlgorithm());
}
if (currentVersion.useTLS10PlusSpec()) {
encrypted = input.getBytes16();
} else {
encrypted = new byte [messageSize];
if (input.read(encrypted) != messageSize) {
throw new SSLProtocolException(
"SSL: read PreMasterSecret: short read");
}
}
byte[] encoded = null;
try {
boolean needFailover = false;
Cipher cipher = JsseJce.getCipher(JsseJce.CIPHER_RSA_PKCS1);
try {
// Try UNWRAP_MODE mode firstly.
cipher.init(Cipher.UNWRAP_MODE, privateKey,
new TlsRsaPremasterSecretParameterSpec(
maxVersion.v, currentVersion.v),
generator);
// The provider selection can be delayed, please don't call
// any Cipher method before the call to Cipher.init().
needFailover = !KeyUtil.isOracleJCEProvider(
cipher.getProvider().getName());
} catch (InvalidKeyException | UnsupportedOperationException iue) {
if (debug != null && Debug.isOn("handshake")) {
System.out.println("The Cipher provider "
+ safeProviderName(cipher)
+ " caused exception: " + iue.getMessage());
}
needFailover = true;
}
if (needFailover) {
// The cipher might be spoiled by unsuccessful call to init(),
// so request a fresh instance
cipher = JsseJce.getCipher(JsseJce.CIPHER_RSA_PKCS1);
// Use DECRYPT_MODE and dispose the previous initialization.
cipher.init(Cipher.DECRYPT_MODE, privateKey);
boolean failed = false;
try {
encoded = cipher.doFinal(encrypted);
} catch (BadPaddingException bpe) {
// Note: encoded == null
failed = true;
}
encoded = KeyUtil.checkTlsPreMasterSecretKey(
maxVersion.v, currentVersion.v,
generator, encoded, failed);
preMaster = generatePreMasterSecret(
maxVersion.v, currentVersion.v,
encoded, generator);
} else {
// the cipher should have been initialized
preMaster = (SecretKey)cipher.unwrap(encrypted,
"TlsRsaPremasterSecret", Cipher.SECRET_KEY);
}
} catch (InvalidKeyException ibk) {
// the message is too big to process with RSA
throw new SSLException(
"Unable to process PreMasterSecret", ibk);
} catch (Exception e) {
// unlikely to happen, otherwise, must be a provider exception
if (debug != null && Debug.isOn("handshake")) {
System.out.println("RSA premaster secret decryption error:");
e.printStackTrace(System.out);
}
throw new RuntimeException("Could not generate dummy secret", e);
}
}
// generate a premaster secret with the specified version number
@SuppressWarnings("deprecation")
private static SecretKey generatePreMasterSecret(
int clientVersion, int serverVersion,
byte[] encodedSecret, SecureRandom generator) {
if (debug != null && Debug.isOn("handshake")) {
System.out.println("Generating a premaster secret");
}
try {
String s = ((clientVersion >= ProtocolVersion.TLS12.v) ?
"SunTls12RsaPremasterSecret" : "SunTlsRsaPremasterSecret");
KeyGenerator kg = JsseJce.getKeyGenerator(s);
kg.init(new TlsRsaPremasterSecretParameterSpec(
clientVersion, serverVersion, encodedSecret),
generator);
return kg.generateKey();
} catch (InvalidAlgorithmParameterException |
NoSuchAlgorithmException iae) {
// unlikely to happen, otherwise, must be a provider exception
if (debug != null && Debug.isOn("handshake")) {
System.out.println("RSA premaster secret generation error:");
iae.printStackTrace(System.out);
}
throw new RuntimeException("Could not generate premaster secret", iae);
}
}
@Override
int messageType() {
return ht_client_key_exchange;
}
@Override
int messageLength() {
if (protocolVersion.useTLS10PlusSpec()) {
return encrypted.length + 2;
} else {
return encrypted.length;
}
}
@Override
void send(HandshakeOutStream s) throws IOException {
if (protocolVersion.useTLS10PlusSpec()) {
s.putBytes16(encrypted);
} else {
s.write(encrypted);
}
}
@Override
void print(PrintStream s) throws IOException {
String version = "version not available/extractable";
byte[] ba = preMaster.getEncoded();
if (ba != null && ba.length >= 2) {
version = ProtocolVersion.valueOf(ba[0], ba[1]).name;
}
s.println("*** ClientKeyExchange, RSA PreMasterSecret, " + version);
}
}