eid_nfc

Reads electronic identity documents through the NFC of an Android phone or an iPhone: the eid transport for the flutter_nfc_kit plugin. With eid_icao, it reads passports and identity cards.

Install

dependencies:
  eid_nfc: ^0.1.0
  eid_icao: ^0.1.0

Platform	Setup
Android 7 and later	minSdk = 24; the NFC permission comes with the plugin
iOS 13 and later, iPhone 7 and later	The NFC entitlement and two Info.plist keys, below

On a computer, a contactless reader is a PC/SC reader: use eid_ccid. No browser can read an identity document: Web NFC, in Chrome on Android, reads NDEF tags but sends no ISO 7816 command.

iOS

In Xcode, add the Near Field Communication Tag Reading capability, which creates Runner.entitlements with:

<key>com.apple.developer.nfc.readersession.formats</key>
<array>
  <string>TAG</string>
</array>

Then, in Info.plist, a reason shown to the user and the application of ICAO documents, without which iOS does not let the chip be read:

<key>NFCReaderUsageDescription</key>
<string>Reads the chip of your passport or identity card.</string>
<key>com.apple.developer.nfc.readersession.iso7816.select-identifiers</key>
<array>
  <string>A0000002471001</string>
</array>

Read a document

import 'package:eid_icao/eid_icao.dart';
import 'package:eid_nfc/eid_nfc.dart';

if (await NfcTransport.availability() != NfcAvailability.available) return;

final transport = await NfcTransport.connect(); // waits for the document
try {
  final document = await IcaoReader(transport).read(
    access: IcaoAccessKey.can('123456'),
    onProgress: (f) => transport.setIosMessage('Reading… ${(f * 100).round()} %'),
  );
  await transport.finish(iosMessage: 'Done');
} on Exception {
  await transport.finish(iosError: 'Could not read the document');
  rethrow;
}

connect throws an NfcCancelledException when the user closes the iOS sheet, and a CardTransportException when no document comes in time (20 seconds by default, on Android) or the tag is not an identity document.

NfcTransport.cancel() stops a wait or a read under way, for a Cancel button: the wait throws an NfcCancelledException, the read fails at its next command with a CardTransportException.

The phone holds one NFC session at a time: a new connect ends the previous one. On iOS the system sheet stays up while connected, a minute at most: finish as soon as the read is done.

Watch

final watcher = IcaoWatcher(
  NfcTerminal(onCancelled: showTryAgainButton),
  accessPrompt: askForCan,
)..start();

NfcTerminal waits for documents one after the other, which suits Android. On iOS each wait opens the system sheet: when the user closes it, the terminal pauses until resume(). A read button calling NfcTransport.connect usually suits iOS better.

Tips

• Hold the document still against the back of the phone, or the top of an iPhone, until the read ends: the face takes a few seconds.
• Some phones do not take extended length commands. Reading works anyway, except Active Authentication with a 2048-bit RSA key, which then fails with a CardTransportException.
• transceiveTimeout (5 seconds) is how long one command may take on Android.

Example

example/ reads a document with its CAN or MRZ, shows the face and the checks, and copies the command log.

License

Released under the MIT licence.

More from COMAPPS

Electronic identity cards in Dart:

Package	What it does
eid	APDUs, ISO 7816-4 file reading and the values national cards share.
eid_belgium	The Belgian eID, Kids ID and residence cards, through their contact chip.
eid_icao	Passports and identity cards with an ICAO 9303 chip.
eid_ccid	The transport for a USB or PC/SC card reader.

Every package COMAPPS publishes is listed at packages.comapps.be.