Official Document for How to Read QR code data from Secure QR code of UIDAI Aadhaar card: https://uidai.gov.in/images/resource/User_manulal_QR_Code_15032019.pdf
Have used zxing scanner to scan Secure QR code, And was able to get details of aadhar card with the help of follow project in Github: https://github.com/dimagi/AadharUID
Some how I figured out how to extract photo and bit_indicator_value from converted byte array with the help of instructions on document
But I am unable to get hashed exact hashed value of email and mobile from Secure QR code of Aadhar card byte array to verify
I am bit confused from this line of above mentioned document in page no 6:
- Post getting signature value, check the value of Email_mobile_present_bit_indicator_value:
- if its 3 then first read mobile from index (Byte array length – 1-256) and then email from index (Byte array length – 1- 256- 32) in reverse order. Each value will be of fix size of 32 byte.
- If Email_mobile_present_bit_indicator_value is 1 then only mobile is present.
- If Email_mobile_present_bit_indicator_value is 2 then only email is present.
- If Email_mobile_present_bit_indicator_value is 0 then no mobile or email present.
- Email and Mobile value will available in byte. Convert into Hexadecimal String. .
I have also prepared last step in document page no 6 but the users mobile/email hash value and documents mobile/email byte arrays hash value never matches
Code snippet:
public ScanResult(String input) {
rawString = input;
// copied from http://www.java-samples.com/showtutorial.php?tutorialid=152
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
Document dom;
try {
//Using factory get an instance of document builder
DocumentBuilder db = dbf.newDocumentBuilder();
// Replace </?xml... with <?xml...
if (input.startsWith("</?")) {
input = input.replaceFirst("</\\?", "<?");
}
// Replace <?xml...?"> with <?xml..."?>
input = input.replaceFirst("^<\\?xml ([^>]+)\\?\">", "<?xml $1\"?>");
//parse using builder to get DOM representation of the XML file
dom = db.parse(new ByteArrayInputStream(input.getBytes("UTF-8")));
} catch (ParserConfigurationException | SAXException | IOException e) {
dom = null;
}
if (rawString.matches("[0-9]*")) {
type = QR_CODE_TYPE_SECURE;
byte[] msgInBytes = null;
try {
msgInBytes = decompressByteArray(new BigInteger(rawString).toByteArray());
} catch (IOException e) {
e.printStackTrace();
}
if (msgInBytes != null) {
int[] delimiters = locateDelimiters(msgInBytes);
String referenceId = getValueInRange(msgInBytes, delimiters[0] + 1, delimiters[1]);
uid = referenceId.substring(0, 4);
name = getValueInRange(msgInBytes, delimiters[1] + 1, delimiters[2]);
dob = formatDate(getValueInRange(msgInBytes, delimiters[2] + 1, delimiters[3]),
new String[] {"dd-MM-yyyy", "dd/MM/yyyy"});
yob = dob.substring(0, 4);
gender = getValueInRange(msgInBytes, delimiters[3] + 1, delimiters[4]);
co = getValueInRange(msgInBytes, delimiters[4] + 1, delimiters[5]);
dist = getValueInRange(msgInBytes, delimiters[5] + 1, delimiters[6]);
lm = getValueInRange(msgInBytes, delimiters[6] + 1, delimiters[7]);
house = getValueInRange(msgInBytes, delimiters[7] + 1, delimiters[8]);
loc = getValueInRange(msgInBytes, delimiters[8] + 1, delimiters[9]);
pc = getValueInRange(msgInBytes, delimiters[9] + 1, delimiters[10]);
po = getValueInRange(msgInBytes, delimiters[10] + 1, delimiters[11]);
state = getValueInRange(msgInBytes, delimiters[11] + 1, delimiters[12]);
street = getValueInRange(msgInBytes, delimiters[12] + 1, delimiters[13]);
subdist = getValueInRange(msgInBytes, delimiters[13] + 1, delimiters[14]);
vtc = getValueInRange(msgInBytes, delimiters[14] + 1, delimiters[15]);
statusCode = STATUS_SUCCESS;
} else {
statusCode = STATUS_PARSE_ERROR;
uid = "";
name = "";
gender = "";
yob = "";
co = "";
house = "";
street = "";
lm = "";
loc = "";
vtc = "";
po = "";
dist = "";
subdist = "";
state = "";
pc = "";
dob = "";
}
} else {
type = QR_CODE_TYPE_UNKNOWN;
statusCode = STATUS_PARSE_ERROR;
uid = "";
name = "";
gender = "";
yob = "";
co = "";
house = "";
street = "";
lm = "";
loc = "";
vtc = "";
po = "";
dist = "";
subdist = "";
state = "";
pc = "";
dob = "";
}
dobGuess = getDobGuess(dob, yob);
statusText = getStatusText(statusCode);
}
private static int[] locateDelimiters(byte[] msgInBytes) {
int[] delimiters = new int[NUMBER_OF_PARAMS_IN_SECURE_QR_CODE + 1];
int index = 0;
int delimiterIndex;
for (int i = 0; i <= NUMBER_OF_PARAMS_IN_SECURE_QR_CODE; i++) {
delimiterIndex = getNextDelimiterIndex(msgInBytes, index);
delimiters[i] = delimiterIndex;
index = delimiterIndex + 1;
}
return delimiters;
}
private static String getValueInRange(byte[] msgInBytes, int start, int end) {
return new String(Arrays.copyOfRange(msgInBytes, start, end), Charset.forName("ISO-8859-1"));
}
private static int getNextDelimiterIndex(byte[] msgInBytes, int index) {
int i = index;
for (; i < msgInBytes.length; i++) {
if (msgInBytes[i] == -1) {
break;
}
}
return i;
}
private static byte[] decompressByteArray(byte[] bytes) throws IOException {
java.io.ByteArrayInputStream bytein = new ByteArrayInputStream(bytes);
java.util.zip.GZIPInputStream gzin = new GZIPInputStream(bytein);
java.io.ByteArrayOutputStream byteout = new ByteArrayOutputStream();
int res = 0;
byte buf[] = new byte[1024];
while (res >= 0) {
res = gzin.read(buf, 0, buf.length);
if (res > 0) {
byteout.write(buf, 0, res);
}
}
return byteout.toByteArray();
}
private String formatDate(String rawDateString, String[] possibleFormats) {
if (rawDateString.equals("")) {
return "";
}
SimpleDateFormat toFormat = new SimpleDateFormat("yyyy-MM-dd");
Date date = null;
ParseException parseException = null;
for (String fromFormatPattern : possibleFormats) {
try {
SimpleDateFormat fromFormat = new SimpleDateFormat(fromFormatPattern);
date = fromFormat.parse(rawDateString);
break;
} catch (ParseException e) {
parseException = e;
}
}
if (date != null) {
return toFormat.format(date);
} else if (parseException != null) {
System.err.println("Expected dob to be in dd/mm/yyyy or yyyy-mm-dd format, got " + rawDateString);
return rawDateString;
} else {
throw new AssertionError("This code is unreachable");
}
}
@NonNull
protected String formatGender(String gender) throws ParseException {
String lowercaseGender = gender.toLowerCase();
if (lowercaseGender.equals("male") || lowercaseGender.equals("m")) {
return "M";
} else if (lowercaseGender.equals("female") || lowercaseGender.equals("f")) {
return "F";
} else if (lowercaseGender.equals("other") || lowercaseGender.equals("o")) {
return "O";
} else {
throw new ParseException("404 gender not found", 0);
}
}
@NonNull
private String getStatusText(int statusCode) {
switch (statusCode) {
case ScanResult.STATUS_SUCCESS:
return "✓";
default:
return "✗";
}
}
@NonNull
private String getDobGuess(String dob, String yob) {
if (dob.equals("")) {
Integer yearInt;
try {
yearInt = Integer.parseInt(yob);
} catch (NumberFormatException e) {
return "";
}
// June 1 of the year
return Integer.toString(yearInt) + "-06-01";
} else {
return dob;
}
}