Signature not valid according to jwt.io

[drewpitchford]

New Issue Checklist

• I have read and understood the CONTRIBUTING guide
• I have read the Documentation
• I have searched for a similar issue in the project and found none

Issue Info

Info	Value
Platform Name	iOS
Platform Version	11.3
Integration Method	manually
Xcode Version	Xcode 9.3
Repro rate	all the time (100%)

Issue Description and Steps

I am integrating JWT into an SDK I am writing. When attempting to encrypt and sign some info to send to our server, I get errors in the signature. I double checked by pasting the encrypted data into jwt.io's tool. It decrypts the headers and payload fine; the only issue is "Signature is invalid". I've basically copy/pasted the example from the docs and still see this error. Below is my code

- (nullable AuthenticationRequestParameters *)ms_getAuthenticationRequestParameters:(NSError *__autoreleasing  _Nullable *)error {
    
    NSString *deviceData = [ThreeDSv2Service shared].attributeString;
    NSString *alg = @"HS256";
    id<JWTAlgorithmDataHolderProtocol> signHolder = [JWTAlgorithmRSFamilyDataHolder new].algorithmName(alg).secret([[self.sdkEphemeralPrivateKeyJwk dataUsingEncoding:NSUTF8StringEncoding] base64EncodedStringWithOptions:0]);
    JWTCodingBuilder *signBuilder = [JWTEncodingBuilder encodePayload:[FormatHelper JSONObjectWithString:deviceData]].addHolder(signHolder);
    JWTCodingResultType *result = signBuilder.result;
    NSString *deviceDataEncrypted = @"";
    if(result.successResult) {
        
        deviceDataEncrypted = result.successResult.encoded;
        NSLog(@"Device data encrypted: %@", deviceDataEncrypted);
    }
    else {
        
        NSLog(@"Error signing: %@", result.errorResult.error);
    }

    if(localError) {
        
        *error = [NSError errorWithDomain:kErrorDomainDefault
                                     code:SDKRuntimeException
                                 userInfo:@{kSDKErrorUserInfoMessageKey: [[ErrorsHelper shared] descriptionFor:FailedToEncryptDeviceInfo], kSDKErrorUserInfoCodeKey: [[ErrorsHelper shared] codeFor:FailedToEncryptDeviceInfo]}];
        return nil;
    }
    
    NSString *sdkAppID = [ApplicationIDService applicationID];
    AuthenticationRequestParameters *parameters = [[AuthenticationRequestParameters alloc] initWithSDKTransactionId:self.transactionId
                                                                                                         deviceData:deviceDataEncrypted
                                                                                              sdkEphemeralPublicKey:self.sdkEphemeralPublicKeyJwk
                                                                                                           sdkAppID:sdkAppID
                                                                                                 sdkReferenceNumber:k3DSGlobalSDKReferenceNumber
                                                                                                     messageVersion:k3DSGlobalMessageVersion];
    return parameters;
}



Example encrypted output:
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.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.R2eHc8xSQqj0Ou659tsCHIrM847IR/J6nENgtwnmhOY=

Is there something I'm missing here? I'd appreciate any help! Thanks!

[lolgear]

@drewpitchford
Complicated example.
However, check parameters:

    NSString *alg = @"HS256";
    [JWTAlgorithmRSFamilyDataHolder new].algorithmName(alg);

Something wrong here.
Algorithm should be "RS256".

Besides, try to separate code in pieces.

    NSString *alg = @"HS256";
    id<JWTAlgorithmDataHolderProtocol> signHolder = [JWTAlgorithmRSFamilyDataHolder new].algorithmName(alg).secret([[self.sdkEphemeralPrivateKeyJwk dataUsingEncoding:NSUTF8StringEncoding] base64EncodedStringWithOptions:0]);

You can't check here secret that you pass to holder. Also you can't check data from which you create base64 string.

    NSString *alg = @"HS256";
    NSData *secretData = [self.sdkEphemeralPrivateKeyJwk dataUsingEncoding:NSUTF8StringEncoding];
    NSString *secretString = [secretData base64EncodedStringWithOptions:0];
    id<JWTAlgorithmDataHolderProtocol> signHolder = [JWTAlgorithmRSFamilyDataHolder new]
    .algorithmName(alg)
    .secret(secretString);

It becomes a bit readable.

[drewpitchford]

Yes, I agree it's not clean code. It's a proof of concept for now. I'll try RS256.

[drewpitchford]

@lolgear Does this lib support JWE? I don't see any specific mention of it anywhere.

To be clear, JWE format such as x.x.x.x.x rather than JWS 'x.x.x'

[lolgear]

@drewpitchford
No, it doesn't support it yet.