diff options
Diffstat (limited to 'src/main/java/eu/siacs/conversations/utils/CryptoHelper.java')
| -rw-r--r-- | src/main/java/eu/siacs/conversations/utils/CryptoHelper.java | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/src/main/java/eu/siacs/conversations/utils/CryptoHelper.java b/src/main/java/eu/siacs/conversations/utils/CryptoHelper.java new file mode 100644 index 00000000..1ef5fb3f --- /dev/null +++ b/src/main/java/eu/siacs/conversations/utils/CryptoHelper.java @@ -0,0 +1,211 @@ +package eu.siacs.conversations.utils; + +import android.os.Bundle; +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.security.MessageDigest; +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.Locale; + +import eu.siacs.conversations.Config; +import eu.siacs.conversations.R; +import eu.siacs.conversations.entities.Message; +import eu.siacs.conversations.xmpp.jid.InvalidJidException; +import eu.siacs.conversations.xmpp.jid.Jid; + +public final class CryptoHelper { + public static final String FILETRANSFER = "?FILETRANSFERv1:"; + private final static char[] hexArray = "0123456789abcdef".toCharArray(); + final public static byte[] ONE = new byte[] { 0, 0, 0, 1 }; + + 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 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 prettifyFingerprint(String fingerprint) { + if (fingerprint==null) { + return ""; + } else if (fingerprint.length() < 40) { + return fingerprint; + } + StringBuilder builder = new StringBuilder(fingerprint.toLowerCase(Locale.US).replaceAll("\\s", "")); + 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); + 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, InvalidJidException, 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) { + emails.add(IETFUtils.valueToString(x500name.getRDNs(BCStyle.EmailAddress)[0].getFirst().getValue())); + } + String name = IETFUtils.valueToString(x500name.getRDNs(BCStyle.CN)[0].getFirst().getValue()); + if (emails.size() >= 1) { + return new Pair<>(Jid.fromString(emails.get(0)), name); + } else { + 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 { + MessageDigest md = MessageDigest.getInstance("SHA-1"); + byte[] fingerprint = md.digest(certificate.getEncoded()); + information.putString("sha1", prettifyFingerprintCert(bytesToHex(fingerprint))); + } catch (Exception e) { + + } + return information; + } catch (CertificateEncodingException e) { + return information; + } + } + + public static int encryptionTypeToText(int encryption) { + switch (encryption) { + case Message.ENCRYPTION_OTR: + return R.string.encryption_choice_otr; + case Message.ENCRYPTION_AXOLOTL: + return R.string.encryption_choice_omemo; + case Message.ENCRYPTION_NONE: + return R.string.encryption_choice_unencrypted; + default: + return R.string.encryption_choice_pgp; + } + } +} |