add (inactive) channel binding end-point code

This commit is contained in:
Daniel Gultsch 2022-09-07 11:08:54 +02:00
parent d4ec1eaf38
commit 018e0d9edf

View file

@ -1,11 +1,24 @@
package eu.siacs.conversations.crypto.sasl;
import android.util.Log;
import org.bouncycastle.jcajce.provider.digest.SHA256;
import org.conscrypt.Conscrypt;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.cert.Certificate;
import java.security.cert.CertificateEncodingException;
import java.security.cert.X509Certificate;
import javax.net.ssl.SSLException;
import javax.net.ssl.SSLPeerUnverifiedException;
import javax.net.ssl.SSLSession;
import javax.net.ssl.SSLSocket;
import eu.siacs.conversations.Config;
import eu.siacs.conversations.entities.Account;
import eu.siacs.conversations.utils.CryptoHelper;
abstract class ScramPlusMechanism extends ScramMechanism {
@ -41,9 +54,59 @@ abstract class ScramPlusMechanism extends ScramMechanism {
"Could not retrieve tls unique. Socket not ready");
}
return unique;
} else if (this.channelBinding == ChannelBinding.TLS_SERVER_END_POINT) {
final byte[] endPoint = getServerEndPointChannelBinding(sslSocket.getSession());
Log.d(Config.LOGTAG, "retrieved endpoint " + CryptoHelper.bytesToHex(endPoint));
return endPoint;
} else {
throw new AuthenticationException(
String.format("%s is not a valid channel binding", ChannelBinding.NONE));
}
}
private byte[] getServerEndPointChannelBinding(final SSLSession session)
throws AuthenticationException {
final Certificate[] certificates;
try {
certificates = session.getPeerCertificates();
} catch (final SSLPeerUnverifiedException e) {
throw new AuthenticationException("Could not verify peer certificates");
}
if (certificates == null || certificates.length == 0) {
throw new AuthenticationException("Could not retrieve peer certificate");
}
final X509Certificate certificate;
if (certificates[0] instanceof X509Certificate) {
certificate = (X509Certificate) certificates[0];
} else {
throw new AuthenticationException("Certificate was not X509");
}
final String algorithm = certificate.getSigAlgName();
final int withIndex = algorithm.indexOf("with");
if (withIndex <= 0) {
throw new AuthenticationException("Unable to parse SigAlgName");
}
final String hashAlgorithm = algorithm.substring(0, withIndex);
final MessageDigest messageDigest;
// https://www.rfc-editor.org/rfc/rfc5929#section-4.1
if ("MD5".equalsIgnoreCase(hashAlgorithm) || "SHA1".equalsIgnoreCase(hashAlgorithm)) {
messageDigest = new SHA256.Digest();
} else {
try {
messageDigest = MessageDigest.getInstance(hashAlgorithm);
} catch (final NoSuchAlgorithmException e) {
throw new AuthenticationException(
"Could not instantiate message digest for " + hashAlgorithm);
}
}
Log.d(Config.LOGTAG, "hashing certificate with " + messageDigest.getAlgorithm());
final byte[] encodedCertificate;
try {
encodedCertificate = certificate.getEncoded();
} catch (final CertificateEncodingException e) {
throw new AuthenticationException("Could not encode certificate");
}
messageDigest.update(encodedCertificate);
return messageDigest.digest();
}
}