diff options
Diffstat (limited to 'src/main/java/de/pixart/messenger/crypto/sasl/ScramSha1.java')
| -rw-r--r-- | src/main/java/de/pixart/messenger/crypto/sasl/ScramSha1.java | 423 |
1 files changed, 212 insertions, 211 deletions
diff --git a/src/main/java/de/pixart/messenger/crypto/sasl/ScramSha1.java b/src/main/java/de/pixart/messenger/crypto/sasl/ScramSha1.java index abff542d4..d21cad37d 100644 --- a/src/main/java/de/pixart/messenger/crypto/sasl/ScramSha1.java +++ b/src/main/java/de/pixart/messenger/crypto/sasl/ScramSha1.java @@ -18,221 +18,222 @@ import de.pixart.messenger.utils.CryptoHelper; import de.pixart.messenger.xml.TagWriter; public class ScramSha1 extends SaslMechanism { - // TODO: When channel binding (SCRAM-SHA1-PLUS) is supported in future, generalize this to indicate support and/or usage. - final private static String GS2_HEADER = "n,,"; - private String clientFirstMessageBare; - final private String clientNonce; - private byte[] serverSignature = null; - private static HMac HMAC; - private static Digest DIGEST; - private static final byte[] CLIENT_KEY_BYTES = "Client Key".getBytes(); - private static final byte[] SERVER_KEY_BYTES = "Server Key".getBytes(); - - public static class KeyPair { - final public byte[] clientKey; - final public byte[] serverKey; - - public KeyPair(final byte[] clientKey, final byte[] serverKey) { - this.clientKey = clientKey; - this.serverKey = serverKey; - } - } - - private static final LruCache<String, KeyPair> CACHE; - - static { - DIGEST = new SHA1Digest(); - HMAC = new HMac(new SHA1Digest()); - CACHE = new LruCache<String, KeyPair>(10) { - protected KeyPair create(final String k) { - // Map keys are "bytesToHex(JID),bytesToHex(password),bytesToHex(salt),iterations". - // 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); - - return new KeyPair(clientKey, serverKey); - } catch (final InvalidKeyException | NumberFormatException e) { - return null; - } - } - }; - } - - private State state = State.INITIAL; - - public ScramSha1(final TagWriter tagWriter, final Account account, final SecureRandom rng) { - super(tagWriter, account, rng); - - // This nonce should be different for each authentication attempt. - clientNonce = new BigInteger(100, this.rng).toString(32); - clientFirstMessageBare = ""; - } - - @Override - public int getPriority() { - return 20; - } - - @Override - public String getMechanism() { - return "SCRAM-SHA-1"; - } - - @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 = Base64.decode(challenge, Base64.DEFAULT); - 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': - /* + // TODO: When channel binding (SCRAM-SHA1-PLUS) is supported in future, generalize this to indicate support and/or usage. + final private static String GS2_HEADER = "n,,"; + private String clientFirstMessageBare; + final private String clientNonce; + private byte[] serverSignature = null; + private static HMac HMAC; + private static Digest DIGEST; + private static final byte[] CLIENT_KEY_BYTES = "Client Key".getBytes(); + private static final byte[] SERVER_KEY_BYTES = "Server Key".getBytes(); + + public static class KeyPair { + final public byte[] clientKey; + final public byte[] serverKey; + + public KeyPair(final byte[] clientKey, final byte[] serverKey) { + this.clientKey = clientKey; + this.serverKey = serverKey; + } + } + + private static final LruCache<String, KeyPair> CACHE; + + static { + DIGEST = new SHA1Digest(); + HMAC = new HMac(new SHA1Digest()); + CACHE = new LruCache<String, KeyPair>(10) { + protected KeyPair create(final String k) { + // Map keys are "bytesToHex(JID),bytesToHex(password),bytesToHex(salt),iterations". + // 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); + + return new KeyPair(clientKey, serverKey); + } catch (final InvalidKeyException | NumberFormatException e) { + return null; + } + } + }; + } + + private State state = State.INITIAL; + + public ScramSha1(final TagWriter tagWriter, final Account account, final SecureRandom rng) { + super(tagWriter, account, rng); + + // This nonce should be different for each authentication attempt. + clientNonce = new BigInteger(100, this.rng).toString(32); + clientFirstMessageBare = ""; + } + + @Override + public int getPriority() { + return 20; + } + + @Override + public String getMechanism() { + return "SCRAM-SHA-1"; + } + + @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 = Base64.decode(challenge, Base64.DEFAULT); + 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"); - } - - 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". - final KeyPair keys = CACHE.get( - CryptoHelper.bytesToHex(account.getJid().toBareJid().toString().getBytes()) + "," - + CryptoHelper.bytesToHex(account.getPassword().getBytes()) + "," - + CryptoHelper.bytesToHex(salt.getBytes()) + "," - + String.valueOf(iterationCount) - ); - 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); - - } catch (final InvalidKeyException e) { - throw new AuthenticationException(e); - } - - final byte[] clientProof = new byte[keys.clientKey.length]; - - 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); - } - } - - public 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; - } - - 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; - } + 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"); + } + + 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". + final KeyPair keys = CACHE.get( + CryptoHelper.bytesToHex(account.getJid().toBareJid().toString().getBytes()) + "," + + CryptoHelper.bytesToHex(account.getPassword().getBytes()) + "," + + CryptoHelper.bytesToHex(salt.getBytes()) + "," + + String.valueOf(iterationCount) + ); + 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); + + } catch (final InvalidKeyException e) { + throw new AuthenticationException(e); + } + + final byte[] clientProof = new byte[keys.clientKey.length]; + + 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); + } + } + + public 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; + } + + 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; + } } |