Sign extension for assert.

Yubico · Nov 7, 2024 · 3018ae2 · 3018ae2
1 parent a2e92d9
commit 3018ae2
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Showing 2 changed files with 71 additions and 39 deletions.
diff --git a/YubiKit/YubiKit/Connections/Shared/Sessions/FIDO2/YKFFIDO2Session.m b/YubiKit/YubiKit/Connections/Shared/Sessions/FIDO2/YKFFIDO2Session.m
@@ -500,33 +500,55 @@ - (void)getAssertionWithClientDataHash:(NSData *)clientDataHash
     }
 
     // Extensions, client authenticator input
-    if (extensions && extensions[@"prf"] && extensions[@"prf"][@"eval"]) {
-        NSString *base64EncodedFirst = extensions[@"prf"][@"eval"][@"first"];
-        NSString *base64EncodedSecond = extensions[@"prf"][@"eval"][@"second"];
-
-        NSData *first = [[[NSData alloc] initWithBase64EncodedString:base64EncodedFirst options:0] ykf_prfSaltData];
-        NSData *second = [[[NSData alloc] initWithBase64EncodedString:base64EncodedSecond options:0] ykf_prfSaltData];
-
-        if (first.length != 32 || (second && second.length != 32)) {
-            [NSException raise:@"Invalid input" format:@"Salt is not 32 bytes long."];
-        }
+    if (extensions) {
         [self executeGetSharedSecretWithCompletion:^(NSData * _Nullable sharedSecret, YKFCBORMap * _Nullable cosePlatformPublicKey, NSError * _Nullable error) {
-            NSMutableData *salts = [NSMutableData new];
-            [salts appendData:first];
-            if (second) {
-                [salts appendData:second];
-            }
-
-            NSData *saltEnc = [salts ykf_aes256EncryptedDataWithKey:sharedSecret];
-            NSData *saltAuth = [saltEnc ykf_fido2HMACWithKey:sharedSecret];
-            NSMutableDictionary *hmacSecretInput = [NSMutableDictionary new];
-            hmacSecretInput[YKFCBORInteger(1)] = cosePlatformPublicKey;
-            hmacSecretInput[YKFCBORInteger(2)] = YKFCBORByteString(saltEnc);
-                                hmacSecretInput[YKFCBORInteger(3)] = YKFCBORByteString([saltAuth subdataWithRange:NSMakeRange(0, 16)]);
-            hmacSecretInput[YKFCBORInteger(4)] = YKFCBORInteger(1); // pin uv auth protocol version
             NSMutableDictionary *authenticatorInputs = [NSMutableDictionary new];
-            authenticatorInputs[YKFCBORTextString(@"hmac-secret")] = YKFCBORMap(hmacSecretInput);
-
+            if (extensions[@"prf"] && extensions[@"prf"][@"eval"]) {
+                NSString *base64EncodedFirst = extensions[@"prf"][@"eval"][@"first"];
+                NSString *base64EncodedSecond = extensions[@"prf"][@"eval"][@"second"];
+
+                NSData *first = [[[NSData alloc] initWithBase64EncodedString:base64EncodedFirst options:0] ykf_prfSaltData];
+                NSData *second = [[[NSData alloc] initWithBase64EncodedString:base64EncodedSecond options:0] ykf_prfSaltData];
+
+                if (first.length != 32 || (second && second.length != 32)) {
+                    [NSException raise:@"Invalid input" format:@"Salt is not 32 bytes long."];
+                }
+                NSMutableData *salts = [NSMutableData new];
+                [salts appendData:first];
+                if (second) {
+                    [salts appendData:second];
+                }
+
+                NSData *saltEnc = [salts ykf_aes256EncryptedDataWithKey:sharedSecret];
+                NSData *saltAuth = [saltEnc ykf_fido2HMACWithKey:sharedSecret];
+                NSMutableDictionary *hmacSecretInput = [NSMutableDictionary new];
+                hmacSecretInput[YKFCBORInteger(1)] = cosePlatformPublicKey;
+                hmacSecretInput[YKFCBORInteger(2)] = YKFCBORByteString(saltEnc);
+                hmacSecretInput[YKFCBORInteger(3)] = YKFCBORByteString([saltAuth subdataWithRange:NSMakeRange(0, 16)]);
+                hmacSecretInput[YKFCBORInteger(4)] = YKFCBORInteger(1); // pin uv auth protocol version
+                authenticatorInputs[YKFCBORTextString(@"hmac-secret")] = YKFCBORMap(hmacSecretInput);
+            }
+            if (extensions[@"sign"] && extensions[@"sign"][@"sign"]) {
+                NSString *phDataString =  extensions[@"sign"][@"sign"][@"phData"];
+                NSData *phData = [[NSData alloc] ykf_initWithWebsafeBase64EncodedString:phDataString dataLength:phDataString.length];
+                NSDictionary *keyHandleDict = extensions[@"sign"][@"sign"][@"keyHandleByCredential"];
+                NSMutableDictionary *decodedKeyHandleDict = [NSMutableDictionary new];
+                for (id key in keyHandleDict) {
+                    decodedKeyHandleDict[key] = [[NSData alloc] ykf_initWithWebsafeBase64EncodedString:keyHandleDict[key] dataLength:((NSString *)keyHandleDict[key]).length];
+                }
+                if (allowList.count == 0) {
+                    [NSException raise:@"Invalid input" format:@"Allow list can not be empty."];
+                }
+                NSString *credentialId = [((YKFFIDO2PublicKeyCredentialDescriptor *) allowList.firstObject).credentialId ykf_websafeBase64EncodedString];
+
+                NSData *keyHandle = decodedKeyHandleDict[credentialId];
+
+                NSMutableDictionary *output = [NSMutableDictionary new];
+                output[YKFCBORInteger(0)] = YKFCBORByteString(phData);
+                output[YKFCBORInteger(5)] = YKFCBORArray(@[YKFCBORByteString(keyHandle)]);
+                authenticatorInputs[YKFCBORTextString(@"sign")] = YKFCBORMap(output);
+            }
+
             YKFFIDO2GetAssertionAPDU *apdu = [[YKFFIDO2GetAssertionAPDU alloc] initWithClientDataHash:clientDataHash
                                                                                                  rpId:rpId
                                                                                             allowList:allowList

diff --git a/YubiKitTests/Tests/FIDO2Tests.swift b/YubiKitTests/Tests/FIDO2Tests.swift
@@ -69,7 +69,7 @@ class FIDO2Tests: XCTestCase {
                 connection.fido2TestSession { session in
                     session.setPin("123456") { _ in
                         session.verifyPin("123456") { error in
-                            session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmES256, options: [YKFFIDO2OptionRK: false]) { response in
+                            session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmES256, options: [YKFFIDO2OptionRK: false]) { response, _ in
                                 print("✅ Created new FIDO2 credential: \(response)")
                                 session.getAssertionAndAssert(response: response, options: [YKFFIDO2OptionUP: true]) { response in
                                     // https://www.w3.org/TR/webauthn/#authenticator-data
@@ -98,7 +98,7 @@ class FIDO2Tests: XCTestCase {
                 connection.fido2TestSession { session in
                     session.setPin("123456") { _ in
                         session.verifyPin("123456") { error in
-                            session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmES256, options: [YKFFIDO2OptionRK: false]) { response in
+                            session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmES256, options: [YKFFIDO2OptionRK: false]) { response, _ in
                                 session.clearUserVerification()
                                 session.getAssertion(response: response, options: [YKFFIDO2OptionUP: true]) { response, error in
                                     if let response = response {
@@ -171,7 +171,7 @@ class FIDO2Tests: XCTestCase {
     func testCreateECCNonRKCredential() {
         runYubiKitTest { connection, completion in
             connection.fido2TestSession { session in
-                session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmES256, options: [YKFFIDO2OptionRK: false]) { response in
+                session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmES256, options: [YKFFIDO2OptionRK: false]) { response, _ in
                     print("✅ New FIDO2 credential: \(response)")
                     completion()
                 }
@@ -182,7 +182,7 @@ class FIDO2Tests: XCTestCase {
     func testCreateEdSANonRKCredential() {
         runYubiKitTest { connection, completion in
             connection.fido2TestSession { session in
-                session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmEdDSA, options: [YKFFIDO2OptionRK: false]) { response in
+                session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmEdDSA, options: [YKFFIDO2OptionRK: false]) { response, _ in
                     print("✅ Created new FIDO2 credential: \(response)")
                     completion()
                 }
@@ -193,7 +193,7 @@ class FIDO2Tests: XCTestCase {
     func testCreateECCNonRKCredentialAndAssert() {
         runYubiKitTest { connection, completion in
             connection.fido2TestSession { session in
-                session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmES256, options: [YKFFIDO2OptionRK: false]) { response in
+                session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmES256, options: [YKFFIDO2OptionRK: false]) { response, _ in
                     print("✅ Created new FIDO2 credential: \(response)")
                     session.getAssertionAndAssert(response: response, options: [YKFFIDO2OptionUP: true]) { response in
                         print("✅ Asserted FIDO2 credential: \(response)")
@@ -207,7 +207,7 @@ class FIDO2Tests: XCTestCase {
     func testCreateEdDSANonRKCredentialAndAssert() {
         runYubiKitTest { connection, completion in
             connection.fido2TestSession { session in
-                session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmEdDSA, options: [YKFFIDO2OptionRK: false]) { response in
+                session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmEdDSA, options: [YKFFIDO2OptionRK: false]) { response, _ in
                     print("✅ Created new FIDO2 credential: \(response)")
                     session.getAssertionAndAssert(response: response, options: [YKFFIDO2OptionUP: true]) { response in
                         print("✅ Asserted FIDO2 credential: \(response)")
@@ -221,7 +221,7 @@ class FIDO2Tests: XCTestCase {
     func testCreateEdDSARKCredentialAndAssert() {
         runYubiKitTest { connection, completion in
             connection.fido2TestSession { session in
-                session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmEdDSA, options: [YKFFIDO2OptionRK: true]) { response in
+                session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmEdDSA, options: [YKFFIDO2OptionRK: true]) { response, _ in
                     print("✅ Created new FIDO2 credential: \(response)")
                     session.getAssertionAndAssert(response: response, options: [YKFFIDO2OptionUP: true]) { response in
                         print("✅ Asserted FIDO2 credential: \(response)")
@@ -235,7 +235,7 @@ class FIDO2Tests: XCTestCase {
     func testCreateEdDSARKCredentialAndAssertWithoutUP() {
         runYubiKitTest { connection, completion in
             connection.fido2TestSession { session in
-                session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmEdDSA, options: [YKFFIDO2OptionRK: true]) { response in
+                session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmEdDSA, options: [YKFFIDO2OptionRK: true]) { response, _ in
                     print("✅ Created new FIDO2 credential: \(response)")
                     session.getAssertionAndAssert(response: response, options: [YKFFIDO2OptionUP: false]) { response in
                         print("✅ Asserted FIDO2 credential: \(response)")
@@ -250,9 +250,19 @@ class FIDO2Tests: XCTestCase {
         runYubiKitTest { connection, completion in
             connection.fido2TestSession { session in
                 let createExtensions = ["sign" : ["generateKey": ["algorithms": [-65539]]]]
-                session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmES256, options: [YKFFIDO2OptionRK: false, YKFFIDO2OptionUV: false], extensions: createExtensions) { response in
+                session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmES256, options: [YKFFIDO2OptionRK: false, YKFFIDO2OptionUV: false], extensions: createExtensions) { response, extensionResponse in
                     print(response.authenticatorData)
-                    print("✅ Created new FIDO2 credential: \(response)")
+                    print("✅ Created new FIDO2 credential: \(response), \(extensionResponse)")
+
+                    let credentialId = (response.authenticatorData!.credentialId! as NSData).ykf_websafeBase64EncodedString()
+                    let sign = (extensionResponse!["sign"] as! [String: Any])
+                    let generatedKey = sign["generatedKey"] as! [String: Any]
+                    let keyHandle = generatedKey["keyHandle"] as! String
+                    let assertExtensions = ["sign" : ["sign" : ["phData" : "Mp80eo3FdxJ2hLtD7HHQO5hhzjyDD57Kdvuqi_weTGE", "keyHandleByCredential" : [credentialId: keyHandle]]]]
+                    session.getAssertionAndAssert(response: response, options: [YKFFIDO2OptionUP: true, YKFFIDO2OptionUV: false], extensions: assertExtensions) { response in
+                        print("✅ Asserted FIDO2 credential: \(response)")
+                        completion()
+                    }
                 }
             }
         }
@@ -264,7 +274,7 @@ class FIDO2Tests: XCTestCase {
                 session.verifyPin("123456") { error in
                     if let error { XCTFail("verifyPin failed with: \(error)"); return }
                     let createExtensions = ["prf" : []]
-                    session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmES256, options: [YKFFIDO2OptionRK: true], extensions: createExtensions) { response in
+                    session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmES256, options: [YKFFIDO2OptionRK: true], extensions: createExtensions) { response, _ in
                         print(response.authenticatorData)
                         print("✅ Created new FIDO2 credential: \(response)")
 
@@ -286,7 +296,7 @@ class FIDO2Tests: XCTestCase {
                     if let error { XCTFail("verifyPin failed with: \(error)"); return }
                     //                    let extensions = ["largeBlobKey" : ["support": "required"]]
                     //                    session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmEdDSA, options: [YKFFIDO2OptionRK: true], extensions: extensions) { response in
-                    session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmEdDSA, options: [YKFFIDO2OptionRK: true]) { response in
+                    session.addCredentialAndAssert(algorithm: YKFFIDO2PublicKeyAlgorithmEdDSA, options: [YKFFIDO2OptionRK: true]) { response, _ in
                         print("✅ Created new FIDO2 credential: \(response)")
                         session.getAssertionAndAssert(response: response, options: [YKFFIDO2OptionUP: true]) { response in
                             print("✅ Asserted FIDO2 credential: \(response)")
@@ -300,15 +310,15 @@ class FIDO2Tests: XCTestCase {
 }
 
 extension YKFFIDO2Session {
-    func addCredentialAndAssert(algorithm: Int, options: [String: Any]? = nil, extensions: [String: Any]? = nil, completion: @escaping (_ response: YKFFIDO2MakeCredentialResponse) -> Void) {
+    func addCredentialAndAssert(algorithm: Int, options: [String: Any]? = nil, extensions: [String: Any]? = nil, completion: @escaping (_ response: YKFFIDO2MakeCredentialResponse, _ clientExtensionResults: [AnyHashable: Any]?) -> Void) {
         addCredential(algorithm: algorithm, options: options, extensions: extensions) { response, clientExtensionResults, error in
             if let clientExtensionResults {
                 let jsonData = try! JSONSerialization.data(withJSONObject: clientExtensionResults)
                 let jsonString = String(data: jsonData, encoding: .utf8)
                 print(jsonString as Any)
             }
             guard let response = response else { XCTAssertTrue(false, "🔴 Failed making FIDO2 credential: \(error!)"); return }
-            completion(response)
+            completion(response, clientExtensionResults)
         }
     }