diff options
| -rw-r--r-- | src/main/java/eu/siacs/conversations/crypto/sasl/ScramSha1.java | 57 | ||||
| -rw-r--r-- | src/main/java/eu/siacs/conversations/utils/CryptoHelper.java | 4 |
2 files changed, 51 insertions, 10 deletions
diff --git a/src/main/java/eu/siacs/conversations/crypto/sasl/ScramSha1.java b/src/main/java/eu/siacs/conversations/crypto/sasl/ScramSha1.java index f3589fa2..f5765cf1 100644 --- a/src/main/java/eu/siacs/conversations/crypto/sasl/ScramSha1.java +++ b/src/main/java/eu/siacs/conversations/crypto/sasl/ScramSha1.java @@ -1,6 +1,7 @@ package eu.siacs.conversations.crypto.sasl; import android.util.Base64; +import android.util.LruCache; import org.bouncycastle.crypto.Digest; import org.bouncycastle.crypto.digests.SHA1Digest; @@ -28,9 +29,40 @@ public class ScramSha1 extends SaslMechanism { 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.saslPrep(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; @@ -118,15 +150,20 @@ public class ScramSha1 extends SaslMechanism { final byte[] authMessage = (clientFirstMessageBare + ',' + new String(serverFirstMessage) + ',' + clientFinalMessageWithoutProof).getBytes(); - // TODO: In future, cache the clientKey and serverKey and re-use them on re-auth. - final byte[] saltedPassword, clientSignature, serverKey, clientKey; + // 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 { - saltedPassword = hi(CryptoHelper.saslPrep(account.getPassword()).getBytes(), - Base64.decode(salt, Base64.DEFAULT), iterationCount); - serverKey = hmac(saltedPassword, SERVER_KEY_BYTES); - serverSignature = hmac(serverKey, authMessage); - clientKey = hmac(saltedPassword, CLIENT_KEY_BYTES); - final byte[] storedKey = digest(clientKey); + serverSignature = hmac(keys.serverKey, authMessage); + final byte[] storedKey = digest(keys.clientKey); clientSignature = hmac(storedKey, authMessage); @@ -134,10 +171,10 @@ public class ScramSha1 extends SaslMechanism { throw new AuthenticationException(e); } - final byte[] clientProof = new byte[clientKey.length]; + final byte[] clientProof = new byte[keys.clientKey.length]; for (int i = 0; i < clientProof.length; i++) { - clientProof[i] = (byte) (clientKey[i] ^ clientSignature[i]); + clientProof[i] = (byte) (keys.clientKey[i] ^ clientSignature[i]); } diff --git a/src/main/java/eu/siacs/conversations/utils/CryptoHelper.java b/src/main/java/eu/siacs/conversations/utils/CryptoHelper.java index bcc54a26..f7126a2f 100644 --- a/src/main/java/eu/siacs/conversations/utils/CryptoHelper.java +++ b/src/main/java/eu/siacs/conversations/utils/CryptoHelper.java @@ -30,6 +30,10 @@ public class CryptoHelper { return array; } + public static String hexToString(final String hexString) { + return new String(hexToBytes(hexString)); + } + public static byte[] concatenateByteArrays(byte[] a, byte[] b) { byte[] result = new byte[a.length + b.length]; System.arraycopy(a, 0, result, 0, a.length); |