1package eu.siacs.conversations.crypto;
2
3import android.util.Log;
4import android.util.Pair;
5
6import org.bouncycastle.asn1.ASN1Primitive;
7import org.bouncycastle.asn1.DERIA5String;
8import org.bouncycastle.asn1.DERTaggedObject;
9import org.bouncycastle.asn1.DERUTF8String;
10import org.bouncycastle.asn1.DLSequence;
11import org.bouncycastle.asn1.x500.RDN;
12import org.bouncycastle.asn1.x500.X500Name;
13import org.bouncycastle.asn1.x500.style.BCStyle;
14import org.bouncycastle.asn1.x500.style.IETFUtils;
15import org.bouncycastle.cert.jcajce.JcaX509CertificateHolder;
16
17import java.io.IOException;
18import java.security.cert.Certificate;
19import java.security.cert.X509Certificate;
20import java.util.ArrayList;
21import java.util.Collection;
22import java.util.List;
23
24import javax.net.ssl.HostnameVerifier;
25import javax.net.ssl.SSLSession;
26
27import de.duenndns.ssl.DomainHostnameVerifier;
28
29public class XmppDomainVerifier implements DomainHostnameVerifier {
30
31 private static final String LOGTAG = "XmppDomainVerifier";
32
33 private final String SRVName = "1.3.6.1.5.5.7.8.7";
34 private final String xmppAddr = "1.3.6.1.5.5.7.8.5";
35
36 @Override
37 public boolean verify(String domain, String hostname, SSLSession sslSession) {
38 try {
39 Certificate[] chain = sslSession.getPeerCertificates();
40 if (chain.length == 0 || !(chain[0] instanceof X509Certificate)) {
41 return false;
42 }
43 X509Certificate certificate = (X509Certificate) chain[0];
44 Collection<List<?>> alternativeNames = certificate.getSubjectAlternativeNames();
45 List<String> xmppAddrs = new ArrayList<>();
46 List<String> srvNames = new ArrayList<>();
47 List<String> domains = new ArrayList<>();
48 if (alternativeNames != null) {
49 for (List<?> san : alternativeNames) {
50 Integer type = (Integer) san.get(0);
51 if (type == 0) {
52 Pair<String, String> otherName = parseOtherName((byte[]) san.get(1));
53 if (otherName != null) {
54 switch (otherName.first) {
55 case SRVName:
56 srvNames.add(otherName.second);
57 break;
58 case xmppAddr:
59 xmppAddrs.add(otherName.second);
60 break;
61 default:
62 Log.d(LOGTAG, "oid: " + otherName.first + " value: " + otherName.second);
63 }
64 }
65 } else if (type == 2) {
66 Object value = san.get(1);
67 if (value instanceof String) {
68 domains.add((String) value);
69 }
70 }
71 }
72 }
73 if (srvNames.size() == 0 && xmppAddrs.size() == 0 && domains.size() == 0) {
74 X500Name x500name = new JcaX509CertificateHolder(certificate).getSubject();
75 RDN[] rdns = x500name.getRDNs(BCStyle.CN);
76 for (int i = 0; i < rdns.length; ++i) {
77 domains.add(IETFUtils.valueToString(x500name.getRDNs(BCStyle.CN)[i].getFirst().getValue()));
78 }
79 }
80 Log.d(LOGTAG, "searching for " + domain + " in srvNames: " + srvNames + " xmppAddrs: " + xmppAddrs + " domains:" + domains);
81 if (hostname != null) {
82 Log.d(LOGTAG,"also trying to verify hostname "+hostname);
83 }
84 return xmppAddrs.contains(domain)
85 || srvNames.contains("_xmpp-client." + domain)
86 || matchDomain(domain, domains)
87 || (hostname != null && matchDomain(hostname,domains));
88 } catch (Exception e) {
89 return false;
90 }
91 }
92
93 private static Pair<String, String> parseOtherName(byte[] otherName) {
94 try {
95 ASN1Primitive asn1Primitive = ASN1Primitive.fromByteArray(otherName);
96 if (asn1Primitive instanceof DERTaggedObject) {
97 ASN1Primitive inner = ((DERTaggedObject) asn1Primitive).getObject();
98 if (inner instanceof DLSequence) {
99 DLSequence sequence = (DLSequence) inner;
100 if (sequence.size() >= 2 && sequence.getObjectAt(1) instanceof DERTaggedObject) {
101 String oid = sequence.getObjectAt(0).toString();
102 ASN1Primitive value = ((DERTaggedObject) sequence.getObjectAt(1)).getObject();
103 if (value instanceof DERUTF8String) {
104 return new Pair<>(oid, ((DERUTF8String) value).getString());
105 } else if (value instanceof DERIA5String) {
106 return new Pair<>(oid, ((DERIA5String) value).getString());
107 }
108 }
109 }
110 }
111 return null;
112 } catch (IOException e) {
113 return null;
114 }
115 }
116
117 private static boolean matchDomain(String needle, List<String> haystack) {
118 for (String entry : haystack) {
119 if (entry.startsWith("*.")) {
120 int i = needle.indexOf('.');
121 Log.d(LOGTAG, "comparing " + needle.substring(i) + " and " + entry.substring(1));
122 if (i != -1 && needle.substring(i).equals(entry.substring(1))) {
123 Log.d(LOGTAG, "domain " + needle + " matched " + entry);
124 return true;
125 }
126 } else {
127 if (entry.equals(needle)) {
128 Log.d(LOGTAG, "domain " + needle + " matched " + entry);
129 return true;
130 }
131 }
132 }
133 return false;
134 }
135
136 @Override
137 public boolean verify(String domain, SSLSession sslSession) {
138 return verify(domain,null,sslSession);
139 }
140}