I'm working on integrating Passkey functionality into my iOS app (targeting iOS 16.0+), and I'm facing an issue where the system dialog still shows the "Save to another device" option during Passkey registration. I want to hide this option to force users to create Passkeys only on the current device.
1. My Current Registration Implementation
Here’s the code I’m using to create a Passkey registration request. I’ve tried to use ASAuthorizationPlatformPublicKeyCredentialProvider (which is supposed to target platform authenticators like Face ID/Touch ID), but the "Save to another device" option still appears:
`// Initialize provider for platform authenticators
let provider = ASAuthorizationPlatformPublicKeyCredentialProvider(relyingPartyIdentifier: domain)
// Create registration request
let registrationRequest = provider.createCredentialRegistrationRequest(
challenge: challenge,
name: username,
userID: userId
)
// Optional configurations (tried these but no effect on "another device" option)
registrationRequest.displayName = "Test Device"
registrationRequest.userVerificationPreference = .required
registrationRequest.attestationPreference = .none
// Set up authorization controller
let authController = ASAuthorizationController(authorizationRequests: [registrationRequest])
let delegate = PasskeyRegistrationDelegate(completion: completion)
authController.delegate = delegate
// Trigger the registration flow
authController.performRequests(options: .preferImmediatelyAvailableCredentials)`
2. Observation from Authentication Flow (Working as Expected)
During the Passkey authentication flow (not registration), I can successfully hide the "Use another device" option by specifying allowedCredentials in the ASAuthorizationPlatformPublicKeyCredentialAssertionRequest. Here’s a simplified example of that working code:
let assertionRequest = provider.createCredentialAssertionRequest(challenge: challenge)
assertionRequest.allowedCredentials = allowedCredentials
After adding allowedCredentials, the system dialog no longer shows cross-device options—this is exactly the behavior I want for registration.
3. My Questions
Is there a similar parameter to allowedCredentials (from authentication) that I can use during registration to hide the "Save to another device" option?
Did I miss any configuration in the registration request (e.g., authenticatorAttachment or other properties) that forces the flow to use only the current device’s platform authenticator?
Are there any system-level constraints or WebAuthn standards I’m overlooking that cause the "Save to another device" option to persist during registration?
Any insights or code examples would be greatly appreciated!
Prioritize user privacy and data security in your app. Discuss best practices for data handling, user consent, and security measures to protect user information.
Selecting any option will automatically load the page
Post
Replies
Boosts
Views
Activity
override func prepareInterface(forPasskeyRegistration registrationRequest: any ASCredentialRequest)
int this function how can i get the "challenge" from user agent, the params "challenge" need to be used in webauthn navigator.credentials.create
Hello, I am currently implementing a biometric authentication registration flow using WebAuthn. I am using ASAuthorizationPlatformPublicKeyCredentialRegistrationRequest, and I would like to know if there is a way to hide the "Save to another device" option that appears during the registration process.
Specifically, I want to guide users to save the passkey only locally on their device, without prompting them to save it to iCloud Keychain or another device.
If there is a way to hide this option or if there is a recommended approach to achieve this, I would greatly appreciate your guidance.
Also, if this is not possible due to iOS version or API limitations, I would be grateful if you could share any best practices for limiting user options in this scenario.
If anyone has experienced a similar issue, your advice would be very helpful. Thank you in advance.
Greetings,
We are struggling to implement device binding according to your documentation. We are generation a nonce value in backend like this:
public static String generateNonce(int byteLength) {
byte[] randomBytes = new byte[byteLength];
new SecureRandom().nextBytes(randomBytes);
return Base64.getUrlEncoder().withoutPadding().encodeToString(randomBytes);
}
And our mobile client implement the attestation flow like this:
@implementation AppAttestModule
- (NSData *)sha256FromString:(NSString *)input {
const char *str = [input UTF8String];
unsigned char result[CC_SHA256_DIGEST_LENGTH];
CC_SHA256(str, (CC_LONG)strlen(str), result);
return [NSData dataWithBytes:result length:CC_SHA256_DIGEST_LENGTH];
}
RCT_EXPORT_MODULE();
RCT_EXPORT_METHOD(generateAttestation:(NSString *)nonce
resolver:(RCTPromiseResolveBlock)resolve
rejecter:(RCTPromiseRejectBlock)reject)
{
if (@available(iOS 14.0, *)) {
DCAppAttestService *service = [DCAppAttestService sharedService];
if (![service isSupported]) {
reject(@"not_supported", @"App Attest is not supported on this device.", nil);
return;
}
NSData *nonceData = [self sha256FromString:nonce];
NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSString *savedKeyId = [defaults stringForKey:@"AppAttestKeyId"];
NSString *savedAttestation = [defaults stringForKey:@"AppAttestAttestationData"];
void (^resolveWithValues)(NSString *keyId, NSData *assertion, NSString *attestationB64) = ^(NSString *keyId, NSData *assertion, NSString *attestationB64) {
NSString *assertionB64 = [assertion base64EncodedStringWithOptions:0];
resolve(@{
@"nonce": nonce,
@"signature": assertionB64,
@"deviceType": @"IOS",
@"attestationData": attestationB64 ?: @"",
@"keyId": keyId
});
};
void (^handleAssertion)(NSString *keyId, NSString *attestationB64) = ^(NSString *keyId, NSString *attestationB64) {
[service generateAssertion:keyId clientDataHash:nonceData completionHandler:^(NSData *assertion, NSError *assertError) {
if (!assertion) {
reject(@"assertion_error", @"Failed to generate assertion", assertError);
return;
}
resolveWithValues(keyId, assertion, attestationB64);
}];
};
if (savedKeyId && savedAttestation) {
handleAssertion(savedKeyId, savedAttestation);
} else {
[service generateKeyWithCompletionHandler:^(NSString *keyId, NSError *keyError) {
if (!keyId) {
reject(@"keygen_error", @"Failed to generate key", keyError);
return;
}
[service attestKey:keyId clientDataHash:nonceData completionHandler:^(NSData *attestation, NSError *attestError) {
if (!attestation) {
reject(@"attestation_error", @"Failed to generate attestation", attestError);
return;
}
NSString *attestationB64 = [attestation base64EncodedStringWithOptions:0];
[defaults setObject:keyId forKey:@"AppAttestKeyId"];
[defaults setObject:attestationB64 forKey:@"AppAttestAttestationData"];
[defaults synchronize];
handleAssertion(keyId, attestationB64);
}];
}];
}
} else {
reject(@"ios_version", @"App Attest requires iOS 14+", nil);
}
}
@end
For validation we are extracting the nonce from the certificate like this:
private static byte[] extractNonceFromAttestationCert(X509Certificate certificate) throws IOException {
byte[] extensionValue = certificate.getExtensionValue("1.2.840.113635.100.8.2");
if (Objects.isNull(extensionValue)) {
throw new IllegalArgumentException("Apple App Attest nonce extension not found in certificate.");
}
ASN1Primitive extensionPrimitive = ASN1Primitive.fromByteArray(extensionValue);
ASN1OctetString outerOctet = ASN1OctetString.getInstance(extensionPrimitive);
ASN1Sequence sequence = (ASN1Sequence) ASN1Primitive.fromByteArray(outerOctet.getOctets());
ASN1TaggedObject taggedObject = (ASN1TaggedObject) sequence.getObjectAt(0);
ASN1OctetString nonceOctet = ASN1OctetString.getInstance(taggedObject.getObject());
return nonceOctet.getOctets();
}
And for the verification we are using this method:
private OptionalMethodResult<Void> verifyNonce(X509Certificate certificate, String expectedNonce, byte[] authData) {
byte[] expectedNonceHash;
try {
byte[] nonceBytes = MessageDigest.getInstance("SHA-256").digest(expectedNonce.getBytes());
byte[] combined = ByteBuffer.allocate(authData.length + nonceBytes.length).put(authData).put(nonceBytes).array();
expectedNonceHash = MessageDigest.getInstance("SHA-256").digest(combined);
} catch (NoSuchAlgorithmException e) {
log.error("Error while validations iOS attestation: {}", e.getMessage(), e);
return OptionalMethodResult.ofError(deviceBindError.getChallengeNotMatchedError());
}
byte[] actualNonceFromCert;
try {
actualNonceFromCert = extractNonceFromAttestationCert(certificate);
} catch (Exception e) {
log.error("Error while extracting nonce from certificate: {}", e.getMessage(), e);
return OptionalMethodResult.ofError(deviceBindError.getChallengeNotMatchedError());
}
if (!Arrays.equals(expectedNonceHash, actualNonceFromCert)) {
return OptionalMethodResult.ofError(deviceBindError.getChallengeNotMatchedError());
}
return OptionalMethodResult.empty();
}
But the values did not matched. What are we doing wrong here?
Thanks.
Hi Community,
We've implemented Sign In with Apple in our application. Our domains are properly registered in the developer console, but we're experiencing inconsistent email functionality with Apple's privacy email service.
Some domains work correctly while others show delivery problems, even though all domains have identical configurations. Apple's console displays green verification status for all domains, yet testing reveals that emails to privacy-protected accounts don't arrive as expected.
We're using SendGrid as our email service provider, and all domains have valid authentication records (SPF, DKIM, DMARC) in place.
Has anyone encountered similar inconsistencies with Apple's privacy email service? Would appreciate any configuration tips or troubleshooting guidance.
Thanks.
I have a custom NSWindow that I want to exclude from screen capture by setting its sharing state to kCGWindowSharingStateSharingNone. The goal is to prevent this window from appearing in the content captured by ScreenCaptureKit.
[window setSharingType:NSWindowSharingType::NSWindowSharingNone];
However, on macOS 15.4+ (Sequoia), the window is still captured by ScreenCaptureKit and appears in the shared content.
Does anyone know if kCGWindowSharingStateSharingNone is still effective with ScreenCaptureKit on macOS 15.4 and later?
Hello.
Some of my users are signing in using "Sign in with Apple" and choosing the "Hide My Email" option. As expected, Apple generates a private relay email address. However, emails that we send to these addresses are not being delivered — the users report that they are not receiving anything.
We’ve configured our email sending domains in the Apple Developer portal, and all domains have been successfully verified with SPF records marked as OK.
Our system is sending the emails as usual, and we're not receiving any bounce-back or error messages. Everything looks fine on our end.
Is there something specific we need to configure to ensure emails sent to privaterelay.appleid.com addresses are delivered correctly?
Are there any known limitations or additional requirements for using Apple's private relay service?
Thank you!
I cannot find any reference to this within the Apple developer documents (or certainly searching for multiple possible keywords yields no results).
The only reference I can find is to documents written in support of its announcement in 2002: https://developer.apple.com/news/?id=huqjyh7k.
Is there any further documentation on implementing or has the capability been deprecated?
Topic:
Privacy & Security
SubTopic:
General
Hi! Is it possible to disable the option for users to 'Sign in with Another Device'? I encounter this message during the authentication process and I want to prevent it from appearing. I appreciate your help and look forward to your response.
I want iOS device identifier for a framework that is used in multiple vendor's apps.
I'm developing a framework to control a peripheral. The framework has to send unique information to register the device with the peripheral.
My naive idea was to use IdentifierForVendor. But this API provides the device identifier for the same vendor's apps, not the framework. (The framework will be used by multiple vendors.)
Is there a usable device identifier for the framework, regardless of app vendor?
Please tell me any solution.
I am working on a SDK which helps identify the device authenticity. I am in need of something which can confirm the firmware/Hardware/OS is signed by Apple and is authentic. There will be no tempering to device?
Hi,
ASCredentialProvider had been almost identically implemented on both iOS and macOS so far, but the ProvidesTextToInsert feature was only added to iOS. It would have been a crucial point to make Credential Providers available in all textfields, without users having to rely on developers correctly setting roles for their Text Fields.
It's right now impossible to paste credentials into Notes, or some other non-password text box both in web and desktop apps for example, in a seamless, OS-supported way without abusing Accessibility APIs which are understandably disallowed in Mac App Store apps. Or just pasting an SSH key, or anything. On macOS this has so many possibilities. It could even have a terminal command.
It's even more interesting that "Passwords..." is an option in macOS's AutoFill context menu, just like on iOS, however Credential Providers did not gain this feature on macOS, only on iOS.
Is this an upcoming feature, or should we find alternatives? Or should I file a feature request? If it's already in the works, it's pointless to file it.
Hi,
Our App relies on a keychain to store certificates and key-value pairs. However, when we upgraded from an older XCode 15.2 (1 year old) app version to a newer version XCode 16.2 (with identical keychain-groups entitlement), we found that the newer ipa cannot see the older keychain group anymore...
We tried Testflight builds, but limited to only generating newer versions, we tried using the older App's code, cast as a newer App version, and then upgraded to the newer code (with an even newer app version!). Surprisingly we were able to see the older keychain group.
So it seems that there's something different between the packaging/profile of the older (1 year) and newer (current) App versions that seems to cause the new version to not see the old keychainGroup...
Any ideas?
Hello everyone,
We recently transferred our iOS app from one Apple Developer account to another, and after the transfer, we encountered a serious issue where all previously stored Keychain data and the local database became inaccessible.
As a result, all users are automatically logged out and lose access to their locally stored data (such as chat history) once they update to the new version signed with the new Team ID.
We understand that Keychain items are tied to the App ID prefix (Team ID), which changes during an app transfer. However, we’re looking for possible workarounds or best practices to avoid user data loss.
Questions:
Is there any reliable method to maintain or migrate access to old Keychain data after an app transfer?
Would reverting the app back to the original developer account and releasing an update from there (to persist or migrate data) before transferring it again be a viable solution?
Has anyone faced a similar issue and found a practical way to handle data persistence during an app transfer?
Any guidance, technical suggestions, or shared experiences would be highly appreciated. This issue is causing major impact for our users, so we’re hoping to find a safe and supported approach.
Thank you,
Mohammed Hassan
Hi everyone,
I'm looking for a way to configure Passkey on iOS so that authentication is only possible using FaceID or TouchID. Specifically, I want to disable the use of passcodes and QR codes for authentication. Additionally, is there a method to detect if the authentication was done using a passcode or QR code?
Thanks for your help!
For security reasons, my application needs to prohibit external devices. If it is determined that the current phone is connected to any external devices, including non MFI authenticated devices, the app will exit. Please tell me how to do it? Thanks for your help.
We are experiencing a significant issue with macOS security alerts that began on July 9th, at approximately 4:40 AM UTC. This alert is incorrectly identifying output files from our snippet tests as malware, causing these files to be blocked and moved to the Trash. This is completely disrupting our automated testing workflows.
Issue Description:
Alert: We are seeing the "Malware Blocked and Moved to Trash" popup window.
Affected Files: The security alert triggers when attempting to execute .par files generated as outputs from our snippet tests. These .par files are unique to each individual test run; they are not a single, static tool.
System-Wide Impact: This issue is impacting multiple macOS hosts across our testing infrastructure.
Timeline: The issue began abruptly on July 9th, at approximately 4:40 AM UTC. Before that time, our tests were functioning correctly.
macOS Versions: The problem is occurring on hosts running both macOS 14.x and 15.x.
Experimental Host: Even after upgrading an experimental host to macOS 15.6 beta 2, the issue persisted.
Local execution: The issue can be reproduced locally.
Observations:
The security system is consistently flagging these snippet test output files as malware.
Since each test generates a new .par file, and this issue is impacting all generated files, the root cause doesn't appear to be specific to the code within the .par files themselves.
This issue is impacting all the snippet tests, making us believe that the root cause is not related to our code.
The sudden and widespread nature of the issue strongly suggests a change in a security database or rule, rather than a change in our testing code.
Questions:
Could a recent update to the XProtect database be the cause of this false positive?
Are there any known issues or recent changes in macOS security mechanisms that could cause this kind of widespread and sudden impact?
What is the recommended way to diagnose and resolve this kind of false positive?
We appreciate any guidance or assistance you can provide. Thank you.
Hi everyone,
I am trying to use ASWebAuthenticationSession to authorize user using OAuth2.
Service Webcredentials is set.
/.well-known/apple-app-site-association file is set.
When using API for iOS > 17.4 using new init with callback: .https(...) everything works as expected, however i cannot make .init(url: ,callbackURLScheme: ....) to work.
How can i intercept callback using iOS <17.4?
Do I really need to use universal links?
callbackURL = https://mydomain.com/auth/callback
The header documentation for the (deprecated) LAContext.evaluatedPolicyDomainState property contains the following:
@warning Please note that the value returned by this property can change exceptionally between major OS versions even if the state of biometry has not changed.
I noticed that the documentation for the new LAContext.domainState property does not contain a similar warning. I also found this related thread from 2016/17.
Is the domainState property not susceptible to changes between major OS versions? Or is this generally not an issue anymore?
Like many/most developers, I gave Connect the info required to comply with the DSA. Perhaps unlike most, I always give unique email addresses so that I can easily track the source of abuse. Yesterday I finally had a phish come in to my DSA address claiming "Message blocked" and doing the standard click-to-login-for-details FOMO bait.
So, yep, DSA just becomes yet another public database that malicious actors can use to target you.
It would be really nice if Apple provided a way to supply our contact info only for legitimate business purposes. Mail Privacy Protection (or similar) for this would be a start.