fixed auth
This commit is contained in:
Daniel Gultsch
parent
ef4cfacaf4
commit
6121217df5
|
|
@ -20,215 +20,214 @@ import eu.siacs.conversations.xml.TagWriter;
|
|||
|
||||
@TargetApi(Build.VERSION_CODES.HONEYCOMB_MR1)
|
||||
abstract class ScramMechanism extends SaslMechanism {
|
||||
// TODO: When channel binding (SCRAM-SHA1-PLUS) is supported in future, generalize this to indicate support and/or usage.
|
||||
private final static String GS2_HEADER = "n,,";
|
||||
private String clientFirstMessageBare;
|
||||
private final String clientNonce;
|
||||
private byte[] serverSignature = null;
|
||||
static HMac HMAC;
|
||||
static Digest DIGEST;
|
||||
private static final byte[] CLIENT_KEY_BYTES = "Client Key".getBytes();
|
||||
private static final byte[] SERVER_KEY_BYTES = "Server Key".getBytes();
|
||||
// TODO: When channel binding (SCRAM-SHA1-PLUS) is supported in future, generalize this to indicate support and/or usage.
|
||||
private final static String GS2_HEADER = "n,,";
|
||||
private static final byte[] CLIENT_KEY_BYTES = "Client Key".getBytes();
|
||||
private static final byte[] SERVER_KEY_BYTES = "Server Key".getBytes();
|
||||
private static final LruCache<String, KeyPair> CACHE;
|
||||
static HMac HMAC;
|
||||
static Digest DIGEST;
|
||||
|
||||
private static class KeyPair {
|
||||
final byte[] clientKey;
|
||||
final byte[] serverKey;
|
||||
static {
|
||||
CACHE = new LruCache<String, KeyPair>(10) {
|
||||
protected KeyPair create(final String k) {
|
||||
// Map keys are "bytesToHex(JID),bytesToHex(password),bytesToHex(salt),iterations,SASL-Mechanism".
|
||||
// Changing any of these values forces a cache miss. `CryptoHelper.bytesToHex()'
|
||||
// is applied to prevent commas in the strings breaking things.
|
||||
final String[] kparts = k.split(",", 5);
|
||||
try {
|
||||
final byte[] saltedPassword, serverKey, clientKey;
|
||||
saltedPassword = hi(CryptoHelper.hexToString(kparts[1]).getBytes(),
|
||||
Base64.decode(CryptoHelper.hexToString(kparts[2]), Base64.DEFAULT), Integer.valueOf(kparts[3]));
|
||||
serverKey = hmac(saltedPassword, SERVER_KEY_BYTES);
|
||||
clientKey = hmac(saltedPassword, CLIENT_KEY_BYTES);
|
||||
|
||||
KeyPair(final byte[] clientKey, final byte[] serverKey) {
|
||||
this.clientKey = clientKey;
|
||||
this.serverKey = serverKey;
|
||||
}
|
||||
}
|
||||
return new KeyPair(clientKey, serverKey);
|
||||
} catch (final InvalidKeyException | NumberFormatException e) {
|
||||
return null;
|
||||
}
|
||||
}
|
||||
};
|
||||
}
|
||||
|
||||
static {
|
||||
CACHE = new LruCache<String, KeyPair>(10) {
|
||||
protected KeyPair create(final String k) {
|
||||
// Map keys are "bytesToHex(JID),bytesToHex(password),bytesToHex(salt),iterations,SASL-Mechanism".
|
||||
// Changing any of these values forces a cache miss. `CryptoHelper.bytesToHex()'
|
||||
// is applied to prevent commas in the strings breaking things.
|
||||
final String[] kparts = k.split(",", 4);
|
||||
try {
|
||||
final byte[] saltedPassword, serverKey, clientKey;
|
||||
saltedPassword = hi(CryptoHelper.hexToString(kparts[1]).getBytes(),
|
||||
Base64.decode(CryptoHelper.hexToString(kparts[2]), Base64.DEFAULT), Integer.valueOf(kparts[3]));
|
||||
serverKey = hmac(saltedPassword, SERVER_KEY_BYTES);
|
||||
clientKey = hmac(saltedPassword, CLIENT_KEY_BYTES);
|
||||
private final String clientNonce;
|
||||
protected State state = State.INITIAL;
|
||||
private String clientFirstMessageBare;
|
||||
private byte[] serverSignature = null;
|
||||
|
||||
return new KeyPair(clientKey, serverKey);
|
||||
} catch (final InvalidKeyException | NumberFormatException e) {
|
||||
return null;
|
||||
}
|
||||
}
|
||||
};
|
||||
}
|
||||
ScramMechanism(final TagWriter tagWriter, final Account account, final SecureRandom rng) {
|
||||
super(tagWriter, account, rng);
|
||||
|
||||
private static final LruCache<String, KeyPair> CACHE;
|
||||
// This nonce should be different for each authentication attempt.
|
||||
clientNonce = CryptoHelper.random(100, rng);
|
||||
clientFirstMessageBare = "";
|
||||
}
|
||||
|
||||
protected State state = State.INITIAL;
|
||||
private static synchronized byte[] hmac(final byte[] key, final byte[] input)
|
||||
throws InvalidKeyException {
|
||||
HMAC.init(new KeyParameter(key));
|
||||
HMAC.update(input, 0, input.length);
|
||||
final byte[] out = new byte[HMAC.getMacSize()];
|
||||
HMAC.doFinal(out, 0);
|
||||
return out;
|
||||
}
|
||||
|
||||
ScramMechanism(final TagWriter tagWriter, final Account account, final SecureRandom rng) {
|
||||
super(tagWriter, account, rng);
|
||||
public static synchronized byte[] digest(byte[] bytes) {
|
||||
DIGEST.reset();
|
||||
DIGEST.update(bytes, 0, bytes.length);
|
||||
final byte[] out = new byte[DIGEST.getDigestSize()];
|
||||
DIGEST.doFinal(out, 0);
|
||||
return out;
|
||||
}
|
||||
|
||||
// This nonce should be different for each authentication attempt.
|
||||
clientNonce = CryptoHelper.random(100,rng);
|
||||
clientFirstMessageBare = "";
|
||||
}
|
||||
/*
|
||||
* Hi() is, essentially, PBKDF2 [RFC2898] with HMAC() as the
|
||||
* pseudorandom function (PRF) and with dkLen == output length of
|
||||
* HMAC() == output length of H().
|
||||
*/
|
||||
private static synchronized byte[] hi(final byte[] key, final byte[] salt, final int iterations)
|
||||
throws InvalidKeyException {
|
||||
byte[] u = hmac(key, CryptoHelper.concatenateByteArrays(salt, CryptoHelper.ONE));
|
||||
byte[] out = u.clone();
|
||||
for (int i = 1; i < iterations; i++) {
|
||||
u = hmac(key, u);
|
||||
for (int j = 0; j < u.length; j++) {
|
||||
out[j] ^= u[j];
|
||||
}
|
||||
}
|
||||
return out;
|
||||
}
|
||||
|
||||
@Override
|
||||
public String getClientFirstMessage() {
|
||||
if (clientFirstMessageBare.isEmpty() && state == State.INITIAL) {
|
||||
clientFirstMessageBare = "n=" + CryptoHelper.saslEscape(CryptoHelper.saslPrep(account.getUsername())) +
|
||||
",r=" + this.clientNonce;
|
||||
state = State.AUTH_TEXT_SENT;
|
||||
}
|
||||
return Base64.encodeToString(
|
||||
(GS2_HEADER + clientFirstMessageBare).getBytes(Charset.defaultCharset()),
|
||||
Base64.NO_WRAP);
|
||||
}
|
||||
@Override
|
||||
public String getClientFirstMessage() {
|
||||
if (clientFirstMessageBare.isEmpty() && state == State.INITIAL) {
|
||||
clientFirstMessageBare = "n=" + CryptoHelper.saslEscape(CryptoHelper.saslPrep(account.getUsername())) +
|
||||
",r=" + this.clientNonce;
|
||||
state = State.AUTH_TEXT_SENT;
|
||||
}
|
||||
return Base64.encodeToString(
|
||||
(GS2_HEADER + clientFirstMessageBare).getBytes(Charset.defaultCharset()),
|
||||
Base64.NO_WRAP);
|
||||
}
|
||||
|
||||
@Override
|
||||
public String getResponse(final String challenge) throws AuthenticationException {
|
||||
switch (state) {
|
||||
case AUTH_TEXT_SENT:
|
||||
if (challenge == null) {
|
||||
throw new AuthenticationException("challenge can not be null");
|
||||
}
|
||||
byte[] serverFirstMessage;
|
||||
try {
|
||||
serverFirstMessage = Base64.decode(challenge, Base64.DEFAULT);
|
||||
} catch (IllegalArgumentException e) {
|
||||
throw new AuthenticationException("Unable to decode server challenge",e);
|
||||
}
|
||||
final Tokenizer tokenizer = new Tokenizer(serverFirstMessage);
|
||||
String nonce = "";
|
||||
int iterationCount = -1;
|
||||
String salt = "";
|
||||
for (final String token : tokenizer) {
|
||||
if (token.charAt(1) == '=') {
|
||||
switch (token.charAt(0)) {
|
||||
case 'i':
|
||||
try {
|
||||
iterationCount = Integer.parseInt(token.substring(2));
|
||||
} catch (final NumberFormatException e) {
|
||||
throw new AuthenticationException(e);
|
||||
}
|
||||
break;
|
||||
case 's':
|
||||
salt = token.substring(2);
|
||||
break;
|
||||
case 'r':
|
||||
nonce = token.substring(2);
|
||||
break;
|
||||
case 'm':
|
||||
/*
|
||||
* RFC 5802:
|
||||
* m: This attribute is reserved for future extensibility. In this
|
||||
* version of SCRAM, its presence in a client or a server message
|
||||
* MUST cause authentication failure when the attribute is parsed by
|
||||
* the other end.
|
||||
*/
|
||||
throw new AuthenticationException("Server sent reserved token: `m'");
|
||||
}
|
||||
}
|
||||
}
|
||||
@Override
|
||||
public String getResponse(final String challenge) throws AuthenticationException {
|
||||
switch (state) {
|
||||
case AUTH_TEXT_SENT:
|
||||
if (challenge == null) {
|
||||
throw new AuthenticationException("challenge can not be null");
|
||||
}
|
||||
byte[] serverFirstMessage;
|
||||
try {
|
||||
serverFirstMessage = Base64.decode(challenge, Base64.DEFAULT);
|
||||
} catch (IllegalArgumentException e) {
|
||||
throw new AuthenticationException("Unable to decode server challenge", e);
|
||||
}
|
||||
final Tokenizer tokenizer = new Tokenizer(serverFirstMessage);
|
||||
String nonce = "";
|
||||
int iterationCount = -1;
|
||||
String salt = "";
|
||||
for (final String token : tokenizer) {
|
||||
if (token.charAt(1) == '=') {
|
||||
switch (token.charAt(0)) {
|
||||
case 'i':
|
||||
try {
|
||||
iterationCount = Integer.parseInt(token.substring(2));
|
||||
} catch (final NumberFormatException e) {
|
||||
throw new AuthenticationException(e);
|
||||
}
|
||||
break;
|
||||
case 's':
|
||||
salt = token.substring(2);
|
||||
break;
|
||||
case 'r':
|
||||
nonce = token.substring(2);
|
||||
break;
|
||||
case 'm':
|
||||
/*
|
||||
* RFC 5802:
|
||||
* m: This attribute is reserved for future extensibility. In this
|
||||
* version of SCRAM, its presence in a client or a server message
|
||||
* MUST cause authentication failure when the attribute is parsed by
|
||||
* the other end.
|
||||
*/
|
||||
throw new AuthenticationException("Server sent reserved token: `m'");
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
if (iterationCount < 0) {
|
||||
throw new AuthenticationException("Server did not send iteration count");
|
||||
}
|
||||
if (nonce.isEmpty() || !nonce.startsWith(clientNonce)) {
|
||||
throw new AuthenticationException("Server nonce does not contain client nonce: " + nonce);
|
||||
}
|
||||
if (salt.isEmpty()) {
|
||||
throw new AuthenticationException("Server sent empty salt");
|
||||
}
|
||||
if (iterationCount < 0) {
|
||||
throw new AuthenticationException("Server did not send iteration count");
|
||||
}
|
||||
if (nonce.isEmpty() || !nonce.startsWith(clientNonce)) {
|
||||
throw new AuthenticationException("Server nonce does not contain client nonce: " + nonce);
|
||||
}
|
||||
if (salt.isEmpty()) {
|
||||
throw new AuthenticationException("Server sent empty salt");
|
||||
}
|
||||
|
||||
final String clientFinalMessageWithoutProof = "c=" + Base64.encodeToString(
|
||||
GS2_HEADER.getBytes(), Base64.NO_WRAP) + ",r=" + nonce;
|
||||
final byte[] authMessage = (clientFirstMessageBare + ',' + new String(serverFirstMessage) + ','
|
||||
+ clientFinalMessageWithoutProof).getBytes();
|
||||
final String clientFinalMessageWithoutProof = "c=" + Base64.encodeToString(
|
||||
GS2_HEADER.getBytes(), Base64.NO_WRAP) + ",r=" + nonce;
|
||||
final byte[] authMessage = (clientFirstMessageBare + ',' + new String(serverFirstMessage) + ','
|
||||
+ clientFinalMessageWithoutProof).getBytes();
|
||||
|
||||
// Map keys are "bytesToHex(JID),bytesToHex(password),bytesToHex(salt),iterations,SASL-Mechanism".
|
||||
final KeyPair keys = CACHE.get(
|
||||
CryptoHelper.bytesToHex(account.getJid().asBareJid().toString().getBytes()) + ","
|
||||
+ CryptoHelper.bytesToHex(account.getPassword().getBytes()) + ","
|
||||
+ CryptoHelper.bytesToHex(salt.getBytes()) + ","
|
||||
+ String.valueOf(iterationCount)
|
||||
+ getMechanism()
|
||||
);
|
||||
if (keys == null) {
|
||||
throw new AuthenticationException("Invalid keys generated");
|
||||
}
|
||||
final byte[] clientSignature;
|
||||
try {
|
||||
serverSignature = hmac(keys.serverKey, authMessage);
|
||||
final byte[] storedKey = digest(keys.clientKey);
|
||||
// Map keys are "bytesToHex(JID),bytesToHex(password),bytesToHex(salt),iterations,SASL-Mechanism".
|
||||
final KeyPair keys = CACHE.get(
|
||||
CryptoHelper.bytesToHex(account.getJid().asBareJid().toString().getBytes()) + ","
|
||||
+ CryptoHelper.bytesToHex(account.getPassword().getBytes()) + ","
|
||||
+ CryptoHelper.bytesToHex(salt.getBytes()) + ","
|
||||
+ String.valueOf(iterationCount) + ","
|
||||
+ getMechanism()
|
||||
);
|
||||
if (keys == null) {
|
||||
throw new AuthenticationException("Invalid keys generated");
|
||||
}
|
||||
final byte[] clientSignature;
|
||||
try {
|
||||
serverSignature = hmac(keys.serverKey, authMessage);
|
||||
final byte[] storedKey = digest(keys.clientKey);
|
||||
|
||||
clientSignature = hmac(storedKey, authMessage);
|
||||
clientSignature = hmac(storedKey, authMessage);
|
||||
|
||||
} catch (final InvalidKeyException e) {
|
||||
throw new AuthenticationException(e);
|
||||
}
|
||||
} catch (final InvalidKeyException e) {
|
||||
throw new AuthenticationException(e);
|
||||
}
|
||||
|
||||
final byte[] clientProof = new byte[keys.clientKey.length];
|
||||
final byte[] clientProof = new byte[keys.clientKey.length];
|
||||
|
||||
for (int i = 0; i < clientProof.length; i++) {
|
||||
clientProof[i] = (byte) (keys.clientKey[i] ^ clientSignature[i]);
|
||||
}
|
||||
for (int i = 0; i < clientProof.length; i++) {
|
||||
clientProof[i] = (byte) (keys.clientKey[i] ^ clientSignature[i]);
|
||||
}
|
||||
|
||||
|
||||
final String clientFinalMessage = clientFinalMessageWithoutProof + ",p=" +
|
||||
Base64.encodeToString(clientProof, Base64.NO_WRAP);
|
||||
state = State.RESPONSE_SENT;
|
||||
return Base64.encodeToString(clientFinalMessage.getBytes(), Base64.NO_WRAP);
|
||||
case RESPONSE_SENT:
|
||||
try {
|
||||
final String clientCalculatedServerFinalMessage = "v=" +
|
||||
Base64.encodeToString(serverSignature, Base64.NO_WRAP);
|
||||
if (!clientCalculatedServerFinalMessage.equals(new String(Base64.decode(challenge, Base64.DEFAULT)))) {
|
||||
throw new Exception();
|
||||
}
|
||||
state = State.VALID_SERVER_RESPONSE;
|
||||
return "";
|
||||
} catch(Exception e) {
|
||||
throw new AuthenticationException("Server final message does not match calculated final message");
|
||||
}
|
||||
default:
|
||||
throw new InvalidStateException(state);
|
||||
}
|
||||
}
|
||||
final String clientFinalMessage = clientFinalMessageWithoutProof + ",p=" +
|
||||
Base64.encodeToString(clientProof, Base64.NO_WRAP);
|
||||
state = State.RESPONSE_SENT;
|
||||
return Base64.encodeToString(clientFinalMessage.getBytes(), Base64.NO_WRAP);
|
||||
case RESPONSE_SENT:
|
||||
try {
|
||||
final String clientCalculatedServerFinalMessage = "v=" +
|
||||
Base64.encodeToString(serverSignature, Base64.NO_WRAP);
|
||||
if (!clientCalculatedServerFinalMessage.equals(new String(Base64.decode(challenge, Base64.DEFAULT)))) {
|
||||
throw new Exception();
|
||||
}
|
||||
state = State.VALID_SERVER_RESPONSE;
|
||||
return "";
|
||||
} catch (Exception e) {
|
||||
throw new AuthenticationException("Server final message does not match calculated final message");
|
||||
}
|
||||
default:
|
||||
throw new InvalidStateException(state);
|
||||
}
|
||||
}
|
||||
|
||||
private static synchronized byte[] hmac(final byte[] key, final byte[] input)
|
||||
throws InvalidKeyException {
|
||||
HMAC.init(new KeyParameter(key));
|
||||
HMAC.update(input, 0, input.length);
|
||||
final byte[] out = new byte[HMAC.getMacSize()];
|
||||
HMAC.doFinal(out, 0);
|
||||
return out;
|
||||
}
|
||||
private static class KeyPair {
|
||||
final byte[] clientKey;
|
||||
final byte[] serverKey;
|
||||
|
||||
public static synchronized byte[] digest(byte[] bytes) {
|
||||
DIGEST.reset();
|
||||
DIGEST.update(bytes, 0, bytes.length);
|
||||
final byte[] out = new byte[DIGEST.getDigestSize()];
|
||||
DIGEST.doFinal(out, 0);
|
||||
return out;
|
||||
}
|
||||
|
||||
/*
|
||||
* Hi() is, essentially, PBKDF2 [RFC2898] with HMAC() as the
|
||||
* pseudorandom function (PRF) and with dkLen == output length of
|
||||
* HMAC() == output length of H().
|
||||
*/
|
||||
private static synchronized byte[] hi(final byte[] key, final byte[] salt, final int iterations)
|
||||
throws InvalidKeyException {
|
||||
byte[] u = hmac(key, CryptoHelper.concatenateByteArrays(salt, CryptoHelper.ONE));
|
||||
byte[] out = u.clone();
|
||||
for (int i = 1; i < iterations; i++) {
|
||||
u = hmac(key, u);
|
||||
for (int j = 0; j < u.length; j++) {
|
||||
out[j] ^= u[j];
|
||||
}
|
||||
}
|
||||
return out;
|
||||
}
|
||||
KeyPair(final byte[] clientKey, final byte[] serverKey) {
|
||||
this.clientKey = clientKey;
|
||||
this.serverKey = serverKey;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in New Issue