cheogram/src/main/java/eu/siacs/conversations/utils/CryptoHelper.java

286 lines
11 KiB
Java

package eu.siacs.conversations.utils;
import android.os.Bundle;
import android.util.Base64;
import android.util.Pair;
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.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.cert.CertificateEncodingException;
import java.security.cert.CertificateParsingException;
import java.security.cert.X509Certificate;
import java.text.Normalizer;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.regex.Pattern;
import eu.siacs.conversations.Config;
import eu.siacs.conversations.R;
import eu.siacs.conversations.entities.Account;
import eu.siacs.conversations.entities.Message;
import eu.siacs.conversations.xmpp.Jid;
public final class CryptoHelper {
public static final Pattern UUID_PATTERN = Pattern.compile("[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}");
final public static byte[] ONE = new byte[]{0, 0, 0, 1};
private static final char[] CHARS = "ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz123456789+-/#$!?".toCharArray();
private static final int PW_LENGTH = 12;
private static final char[] VOWELS = "aeiou".toCharArray();
private static final char[] CONSONANTS = "bcfghjklmnpqrstvwxyz".toCharArray();
private final static char[] hexArray = "0123456789abcdef".toCharArray();
public static String bytesToHex(byte[] bytes) {
char[] hexChars = new char[bytes.length * 2];
for (int j = 0; j < bytes.length; j++) {
int v = bytes[j] & 0xFF;
hexChars[j * 2] = hexArray[v >>> 4];
hexChars[j * 2 + 1] = hexArray[v & 0x0F];
}
return new String(hexChars);
}
public static String createPassword(SecureRandom random) {
StringBuilder builder = new StringBuilder(PW_LENGTH);
for (int i = 0; i < PW_LENGTH; ++i) {
builder.append(CHARS[random.nextInt(CHARS.length - 1)]);
}
return builder.toString();
}
public static String pronounceable(SecureRandom random) {
final int rand = random.nextInt(4);
char[] output = new char[rand * 2 + (5 - rand)];
boolean vowel = random.nextBoolean();
for (int i = 0; i < output.length; ++i) {
output[i] = vowel ? VOWELS[random.nextInt(VOWELS.length)] : CONSONANTS[random.nextInt(CONSONANTS.length)];
vowel = !vowel;
}
return String.valueOf(output);
}
public static byte[] hexToBytes(String hexString) {
int len = hexString.length();
byte[] array = new byte[len / 2];
for (int i = 0; i < len; i += 2) {
array[i / 2] = (byte) ((Character.digit(hexString.charAt(i), 16) << 4) + Character
.digit(hexString.charAt(i + 1), 16));
}
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);
System.arraycopy(b, 0, result, a.length, b.length);
return result;
}
/**
* Escapes usernames or passwords for SASL.
*/
public static String saslEscape(final String s) {
final StringBuilder sb = new StringBuilder((int) (s.length() * 1.1));
for (int i = 0; i < s.length(); i++) {
char c = s.charAt(i);
switch (c) {
case ',':
sb.append("=2C");
break;
case '=':
sb.append("=3D");
break;
default:
sb.append(c);
break;
}
}
return sb.toString();
}
public static String saslPrep(final String s) {
return Normalizer.normalize(s, Normalizer.Form.NFKC);
}
public static String random(int length, SecureRandom random) {
final byte[] bytes = new byte[length];
random.nextBytes(bytes);
return Base64.encodeToString(bytes, Base64.NO_PADDING | Base64.NO_WRAP | Base64.URL_SAFE);
}
public static String prettifyFingerprint(String fingerprint) {
if (fingerprint == null) {
return "";
} else if (fingerprint.length() < 40) {
return fingerprint;
}
StringBuilder builder = new StringBuilder(fingerprint);
for (int i = 8; i < builder.length(); i += 9) {
builder.insert(i, ' ');
}
return builder.toString();
}
public static String prettifyFingerprintCert(String fingerprint) {
StringBuilder builder = new StringBuilder(fingerprint);
for (int i = 2; i < builder.length(); i += 3) {
builder.insert(i, ':');
}
return builder.toString();
}
public static String[] getOrderedCipherSuites(final String[] platformSupportedCipherSuites) {
final Collection<String> cipherSuites = new LinkedHashSet<>(Arrays.asList(Config.ENABLED_CIPHERS));
final List<String> platformCiphers = Arrays.asList(platformSupportedCipherSuites);
cipherSuites.retainAll(platformCiphers);
cipherSuites.addAll(platformCiphers);
filterWeakCipherSuites(cipherSuites);
cipherSuites.remove("TLS_FALLBACK_SCSV");
return cipherSuites.toArray(new String[cipherSuites.size()]);
}
private static void filterWeakCipherSuites(final Collection<String> cipherSuites) {
final Iterator<String> it = cipherSuites.iterator();
while (it.hasNext()) {
String cipherName = it.next();
// remove all ciphers with no or very weak encryption or no authentication
for (String weakCipherPattern : Config.WEAK_CIPHER_PATTERNS) {
if (cipherName.contains(weakCipherPattern)) {
it.remove();
break;
}
}
}
}
public static Pair<Jid, String> extractJidAndName(X509Certificate certificate) throws CertificateEncodingException, IllegalArgumentException, CertificateParsingException {
Collection<List<?>> alternativeNames = certificate.getSubjectAlternativeNames();
List<String> emails = new ArrayList<>();
if (alternativeNames != null) {
for (List<?> san : alternativeNames) {
Integer type = (Integer) san.get(0);
if (type == 1) {
emails.add((String) san.get(1));
}
}
}
X500Name x500name = new JcaX509CertificateHolder(certificate).getSubject();
if (emails.size() == 0 && x500name.getRDNs(BCStyle.EmailAddress).length > 0) {
emails.add(IETFUtils.valueToString(x500name.getRDNs(BCStyle.EmailAddress)[0].getFirst().getValue()));
}
String name = x500name.getRDNs(BCStyle.CN).length > 0 ? IETFUtils.valueToString(x500name.getRDNs(BCStyle.CN)[0].getFirst().getValue()) : null;
if (emails.size() >= 1) {
return new Pair<>(Jid.of(emails.get(0)), name);
} else if (name != null) {
try {
Jid jid = Jid.of(name);
if (jid.isBareJid() && jid.getLocal() != null) {
return new Pair<>(jid, null);
}
} catch (IllegalArgumentException e) {
return null;
}
}
return null;
}
public static Bundle extractCertificateInformation(X509Certificate certificate) {
Bundle information = new Bundle();
try {
JcaX509CertificateHolder holder = new JcaX509CertificateHolder(certificate);
X500Name subject = holder.getSubject();
try {
information.putString("subject_cn", subject.getRDNs(BCStyle.CN)[0].getFirst().getValue().toString());
} catch (Exception e) {
//ignored
}
try {
information.putString("subject_o", subject.getRDNs(BCStyle.O)[0].getFirst().getValue().toString());
} catch (Exception e) {
//ignored
}
X500Name issuer = holder.getIssuer();
try {
information.putString("issuer_cn", issuer.getRDNs(BCStyle.CN)[0].getFirst().getValue().toString());
} catch (Exception e) {
//ignored
}
try {
information.putString("issuer_o", issuer.getRDNs(BCStyle.O)[0].getFirst().getValue().toString());
} catch (Exception e) {
//ignored
}
try {
information.putString("sha1", getFingerprintCert(certificate.getEncoded()));
} catch (Exception e) {
}
return information;
} catch (CertificateEncodingException e) {
return information;
}
}
public static String getFingerprintCert(byte[] input) throws NoSuchAlgorithmException {
MessageDigest md = MessageDigest.getInstance("SHA-1");
byte[] fingerprint = md.digest(input);
return prettifyFingerprintCert(bytesToHex(fingerprint));
}
public static String getFingerprint(Jid jid, String androidId) {
return getFingerprint(jid.toEscapedString() + "\00" + androidId);
}
public static String getAccountFingerprint(Account account, String androidId) {
return getFingerprint(account.getJid().asBareJid(), androidId);
}
public static String getFingerprint(String value) {
try {
MessageDigest md = MessageDigest.getInstance("SHA-1");
return bytesToHex(md.digest(value.getBytes(StandardCharsets.UTF_8)));
} catch (Exception e) {
return "";
}
}
public static int encryptionTypeToText(int encryption) {
switch (encryption) {
case Message.ENCRYPTION_OTR:
return R.string.encryption_choice_otr;
case Message.ENCRYPTION_AXOLOTL:
case Message.ENCRYPTION_AXOLOTL_NOT_FOR_THIS_DEVICE:
case Message.ENCRYPTION_AXOLOTL_FAILED:
return R.string.encryption_choice_omemo;
case Message.ENCRYPTION_NONE:
return R.string.encryption_choice_unencrypted;
default:
return R.string.encryption_choice_pgp;
}
}
public static boolean isPgpEncryptedUrl(String url) {
if (url == null) {
return false;
}
final String u = url.toLowerCase();
return !u.contains(" ") && (u.startsWith("https://") || u.startsWith("http://") || u.startsWith("p1s3://")) && u.endsWith(".pgp");
}
}