1 files changed, 113 insertions, 0 deletions
diff --git a/src/main/java/eu/siacs/conversations/crypto/XmppDomainVerifier.java b/src/main/java/eu/siacs/conversations/crypto/XmppDomainVerifier.java
new file mode 100644
index 00000000..0052998e
--- /dev/null
+++ b/src/main/java/eu/siacs/conversations/crypto/XmppDomainVerifier.java
@@ -0,0 +1,113 @@
+package eu.siacs.conversations.crypto;
+
+import android.util.Log;
+
+import org.bouncycastle.asn1.ASN1Primitive;
+import org.bouncycastle.asn1.DERIA5String;
+import org.bouncycastle.asn1.DERTaggedObject;
+import org.bouncycastle.asn1.DERUTF8String;
+import org.bouncycastle.asn1.DLSequence;
+import org.bouncycastle.asn1.x500.RDN;
+import org.bouncycastle.asn1.x500.X500Name;
+import org.bouncycastle.asn1.x500.style.BCStyle;
+import org.bouncycastle.asn1.x500.style.IETFUtils;
+import org.bouncycastle.cert.jcajce.JcaX509CertificateHolder;
+
+import java.io.IOException;
+import java.security.cert.X509Certificate;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+
+import javax.net.ssl.HostnameVerifier;
+import javax.net.ssl.SSLSession;
+
+public class XmppDomainVerifier implements HostnameVerifier {
+
+	private final String LOGTAG = "XmppDomainVerifier";
+
+	@Override
+	public boolean verify(String domain, SSLSession sslSession) {
+		try {
+			X509Certificate[] chain = (X509Certificate[]) sslSession.getPeerCertificates();
+			Collection<List<?>> alternativeNames = chain[0].getSubjectAlternativeNames();
+			List<String> xmppAddrs = new ArrayList<>();
+			List<String> srvNames = new ArrayList<>();
+			List<String> domains = new ArrayList<>();
+			if (alternativeNames != null) {
+				for(List<?> san : alternativeNames) {
+					Integer type = (Integer) san.get(0);
+					if (type == 0) {
+						try {
+							ASN1Primitive asn1Primitive = ASN1Primitive.fromByteArray((byte[]) san.get(1));
+							if (asn1Primitive instanceof  DERTaggedObject) {
+								ASN1Primitive inner = ((DERTaggedObject) asn1Primitive).getObject();
+								if (inner instanceof  DLSequence) {
+									DLSequence sequence = (DLSequence) inner;
+									if (sequence.size() >= 2 && sequence.getObjectAt(1) instanceof DERTaggedObject) {
+										String oid = sequence.getObjectAt(0).toString();
+										ASN1Primitive value  = ((DERTaggedObject) sequence.getObjectAt(1)).getObject();
+										switch (oid) {
+											case "1.3.6.1.5.5.7.8.5":
+												if (value instanceof DERUTF8String) {
+													xmppAddrs.add(((DERUTF8String) value).getString());
+												} else if (value instanceof DERIA5String) {
+													xmppAddrs.add(((DERIA5String) value).getString());
+												}
+												break;
+											case "1.3.6.1.5.5.7.8.7":
+												if (value instanceof DERUTF8String) {
+													srvNames.add(((DERUTF8String) value).getString());
+												} else if (value instanceof DERIA5String) {
+													srvNames.add(((DERIA5String) value).getString());
+												}
+												break;
+											default:
+												Log.d(LOGTAG,"value was of type:"+value.getClass().getName()+ " oid was:"+oid);
+										}
+									}
+								}
+							}
+						} catch (IOException e) {
+							//ignored
+						}
+					} else if (type == 2) {
+						Object value = san.get(1);
+						if (value instanceof String) {
+							domains.add((String) value);
+						}
+					}
+				}
+			}
+			if (srvNames.size() == 0 && xmppAddrs.size() == 0 && domains.size() == 0) {
+				X500Name x500name = new JcaX509CertificateHolder(chain[0]).getSubject();
+				RDN[] rdns = x500name.getRDNs(BCStyle.CN);
+				for(int i = 0; i < rdns.length; ++i) {
+					domains.add(IETFUtils.valueToString(x500name.getRDNs(BCStyle.CN)[i].getFirst().getValue()));
+				}
+			}
+			Log.d(LOGTAG, "searching for " + domain + " in srvNames: " + srvNames + " xmppAddrs: " + xmppAddrs + " domains:" + domains);
+			return xmppAddrs.contains(domain) || srvNames.contains("_xmpp-client."+domain) || matchDomain(domain, domains);
+		} catch (Exception e) {
+			return false;
+		}
+	}
+
+	private boolean matchDomain(String needle, List<String> haystack) {
+		for(String entry : haystack) {
+			if (entry.startsWith("*.")) {
+				int i = needle.indexOf('.');
+				if (i != -1 && needle.substring(i).equals(entry.substring(2))) {
+					Log.d(LOGTAG,"domain "+needle+" matched "+entry);
+					return true;
+				}
+			} else {
+				if (entry.equals(needle)) {
+					Log.d(LOGTAG,"domain "+needle+" matched "+entry);
+					return true;
+				}
+			}
+		}
+		return false;
+	}
+}