anotherim/src/eu/siacs/conversations/utils/CryptoHelper.java

105 lines
3.6 KiB
Java

package eu.siacs.conversations.utils;
import java.math.BigInteger;
import java.nio.charset.Charset;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.util.Random;
import eu.siacs.conversations.entities.Account;
import android.util.Base64;
import android.util.Log;
public class CryptoHelper {
final protected static char[] hexArray = "0123456789ABCDEF".toCharArray();
final protected static char[] vowels = "aeiou".toCharArray();
final protected static char[] consonants = "bcdfghjklmnpqrstvwxyz"
.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).toLowerCase();
}
public static String saslPlain(String username, String password) {
String sasl = '\u0000' + username + '\u0000' + password;
return Base64.encodeToString(sasl.getBytes(Charset.defaultCharset()),
Base64.NO_WRAP);
}
private 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;
}
public static String saslDigestMd5(Account account, String challenge) {
try {
Random random = new SecureRandom();
String[] challengeParts = new String(Base64.decode(challenge,
Base64.DEFAULT)).split(",");
String nonce = "";
for (int i = 0; i < challengeParts.length; ++i) {
String[] parts = challengeParts[i].split("=");
if (parts[0].equals("nonce")) {
nonce = parts[1].replace("\"", "");
} else if (parts[0].equals("rspauth")) {
return null;
}
}
String digestUri = "xmpp/"+account.getServer();
String nonceCount = "00000001";
String x = account.getUsername() + ":" + account.getServer() + ":"
+ account.getPassword();
MessageDigest md = MessageDigest.getInstance("MD5");
byte[] y = md
.digest(x.getBytes(Charset.defaultCharset()));
String cNonce = new BigInteger(100, random).toString(32);
byte[] a1 = concatenateByteArrays(y,(":"+nonce+":"+cNonce).getBytes(Charset.defaultCharset()));
String a2 = "AUTHENTICATE:"+digestUri;
String ha1 = bytesToHex(md.digest(a1));
String ha2 = bytesToHex(md.digest(a2.getBytes(Charset
.defaultCharset())));
String kd = ha1 + ":" + nonce + ":"+nonceCount+":" + cNonce + ":auth:"
+ ha2;
String response = bytesToHex(md.digest(kd.getBytes(Charset
.defaultCharset())));
String saslString = "username=\"" + account.getUsername()
+ "\",realm=\"" + account.getServer() + "\",nonce=\""
+ nonce + "\",cnonce=\"" + cNonce
+ "\",nc="+nonceCount+",qop=auth,digest-uri=\""+digestUri+"\",response=" + response
+ ",charset=utf-8";
return Base64.encodeToString(
saslString.getBytes(Charset.defaultCharset()),
Base64.NO_WRAP);
} catch (NoSuchAlgorithmException e) {
return null;
}
}
public static String randomMucName() {
Random random = new SecureRandom();
return randomWord(3, random) + "." + randomWord(7, random);
}
protected static String randomWord(int lenght, Random random) {
StringBuilder builder = new StringBuilder(lenght);
for (int i = 0; i < lenght; ++i) {
if (i % 2 == 0) {
builder.append(consonants[random.nextInt(consonants.length)]);
} else {
builder.append(vowels[random.nextInt(vowels.length)]);
}
}
return builder.toString();
}
}