otp auto picker in php
public class AppSignatureHelper extends ContextWrapper {
private static final String TAG = "AppSignatureHelper";
private static final String HASH_TYPE = "SHA-256";
public static final int NUM_HASHED_BYTES = 9;
public static final int NUM_BASE64_CHAR = 11;
public AppSignatureHelper(Context context) {
super(context);
}
/**
* Get the app signatures for the your current package
*/
public ArrayList<String> getAppSignatures() {
ArrayList<String> appCodes = new ArrayList<>();
try {
// Get all package signatures for the current package
String packageName = getPackageName();
PackageManager packageManager = getPackageManager();
Signature[] signatures = packageManager.getPackageInfo(packageName,
PackageManager.GET_SIGNATURES).signatures;
// For each signature create a compatible hash
for (Signature signature : signatures) {
String hash = hash(packageName, signature.toCharsString());
if (hash != null) {
appCodes.add(String.format("%s", hash));
}
}
} catch (PackageManager.NameNotFoundException e) {
Log.e(TAG, "Unable to find package to obtain hash.", e);
}
return appCodes;
}
private static String hash(String packageName, String signature) {
String appInfo = packageName + " " + signature;
try {
MessageDigest messageDigest = MessageDigest.getInstance(HASH_TYPE);
messageDigest.update(appInfo.getBytes(StandardCharsets.UTF_8));
byte[] hashSignature = messageDigest.digest();
// truncated into NUM_HASHED_BYTES
hashSignature = Arrays.copyOfRange(hashSignature, 0, NUM_HASHED_BYTES);
// encode into Base64
String base64Hash = Base64.encodeToString(hashSignature, Base64.NO_PADDING | Base64.NO_WRAP);
base64Hash = base64Hash.substring(0, NUM_BASE64_CHAR);
Log.d(TAG, String.format("pkg: %s -- hash: %s", packageName, base64Hash));
return base64Hash;
} catch (NoSuchAlgorithmException e) {
Log.e(TAG, "hash:NoSuchAlgorithm", e);
}
return null;
}
}