Question

I’m trying to use the following code to handle SSL connections in iOS. It works fine on a real device and the certificate is issued by a fully trusted CA. It crashes when I try to run it from a unit test. Anyone else seen this sort of behaviour or know a workaround?

- (BOOL) connection:(NSURLConnection *)aConnection canAuthenticateAgainstProtectionSpace:(NSURLProtectionSpace *)protectionSpace {
    NSString *authenticationMethod = protectionSpace.authenticationMethod;
    NSLog(@"Authentication method: %@", authenticationMethod);
    return [authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust];
}

- (void) connection:(NSURLConnection *)aConnection didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge {
    NSLog(@"Challenge: %@", challenge);
    NSURLCredential *proposedCredential = [challenge proposedCredential];
    NSLog(@"proposedCredential = %@", proposedCredential);

    NSURLProtectionSpace *protectionSpace = challenge.protectionSpace;
    NSLog(@"protectionSpace = %@", protectionSpace);

    NSString *host = protectionSpace.host;
    NSLog(@"Trust host: %@", host);
    id <NSURLAuthenticationChallengeSender> sender = challenge.sender;
    NSLog(@"sender = %@", sender);

    if ([protectionSpace.authenticationMethod isEqualToString:NSURLAuthenticationMethodServerTrust]) {
        if ([trustedHosts containsObject:host]) {
            SecTrustRef trust = protectionSpace.serverTrust;
            NSLog(@"trust %p", trust);
            NSURLCredential *credential = [NSURLCredential credentialForTrust:trust];
            NSLog(@"Credential: %@", credential);


            SecTrustResultType result;
            OSStatus status = SecTrustEvaluate(trust, &result);
            NSLog(@"Trust result: %lu", result);
            NSLog(@"OSStatus = %li", status);

            NSError *error = [challenge error];
            NSLog(@"error = %@", error);

            [sender useCredential:credential forAuthenticationChallenge:challenge];
            NSLog(@"Using credential");
        } else {
            [sender performDefaultHandlingForAuthenticationChallenge:challenge];
        }
    } else {
        [sender performDefaultHandlingForAuthenticationChallenge:challenge];
    }
}

The test case output in AppCode is as follows:

2012-03-06 14:35:09.656 otest[5696:7803] About to login
2012-03-06 14:35:09.656 otest[5696:7803] AccountVerificationService - postAccountInfo
2012-03-06 14:35:09.658 otest[5696:7803] POST url: https://secure.example.com/user/verify
2012-03-06 14:35:09.662 otest[5696:7803] Login called
2012-03-06 14:35:09.949 otest[5696:7803] Authentication method: NSURLAuthenticationMethodServerTrust
2012-03-06 14:35:09.953 otest[5696:7803] Challenge: <NSURLAuthenticationChallenge: 0x1b8ded0>
2012-03-06 14:35:09.956 otest[5696:7803] proposedCredential = (null)
2012-03-06 14:35:09.956 otest[5696:7803] protectionSpace = <NSURLProtectionSpace: 0x1b8df00>
2012-03-06 14:35:09.957 otest[5696:7803] Trust host: secure.example.com
2012-03-06 14:35:09.958 otest[5696:7803] sender = <NSURLConnection: 0x1b8d0d0>
2012-03-06 14:35:09.958 otest[5696:7803] trust 0x1d8fb90
2012-03-06 14:35:09.962 otest[5696:7803] Credential: <NSURLCredential: 0x1b8e460>: (null)
2012-03-06 14:35:09.983 otest[5696:7803] Trust result: 7
2012-03-06 14:35:10.001 otest[5696:7803] OSStatus = 0
2012-03-06 14:35:10.011 otest[5696:7803] error = (null)

Process finished with exit code 138

Debug backtrace:

  thread #4: tid = 0x3603, 0x0039a841 CoreFoundation`CFArrayGetCount + 17, stop reason = EXC_BAD_ACCESS (code=2, address=0x0)
    frame #0: 0x0039a841 CoreFoundation`CFArrayGetCount + 17
    frame #1: 0x00dad4f4 Security`SecTrustCopyExceptions + 35
    frame #2: 0x00b318e4 CFNetwork`SocketStream::securityAcceptPeerTrust_NoLock(unsigned char) + 150
    frame #3: 0x00b3a154 CFNetwork`SocketStream::setProperty(void const*, __CFString const*, void const*) + 2754
    frame #4: 0x00b39688 CFNetwork`virtual thunk to SocketStream::setProperty(void const*, __CFString const*, void const*) + 43
    frame #5: 0x00b3ad3b CFNetwork`ReadStreamCallbacks::_setProperty(__CFReadStream*, __CFString const*, void const*, void*) + 53
    frame #6: 0x00429b40 CoreFoundation`CFReadStreamSetProperty + 160
    frame #7: 0x00b3acee CFNetwork`HTTPReadFilter::streamSetProperty(__CFReadStream*, __CFString const*, void const*) + 266
    frame #8: 0x00bd4381 CFNetwork`non-virtual thunk to HTTPReadFilter::streamSetProperty(__CFReadStream*, __CFString const*, void const*) + 41
    frame #9: 0x00b37488 CFNetwork`CFNetworkReadStream::httpStreamSetProperty(__CFReadStream*, __CFString const*, void const*, void*) + 38
    frame #10: 0x00429b40 CoreFoundation`CFReadStreamSetProperty + 160
    frame #11: 0x00b41b88 CFNetwork`HTTPNetStreamInfo::streamSetProperty(__CFReadStream*, __CFString const*, void const*) + 404
    frame #12: 0x00b419ec CFNetwork`non-virtual thunk to HTTPNetStreamInfo::streamSetProperty(__CFReadStream*, __CFString const*, void const*) + 41
    frame #13: 0x00b37488 CFNetwork`CFNetworkReadStream::httpStreamSetProperty(__CFReadStream*, __CFString const*, void const*, void*) + 38
    frame #14: 0x00429b40 CoreFoundation`CFReadStreamSetProperty + 160
    frame #15: 0x00be3e7b CFNetwork`HTTPProtocol::useCredential(_CFURLCredential const*, _CFURLAuthChallenge*) + 125
    frame #16: 0x00bfa9e3 CFNetwork`URLConnectionLoader::loaderUseCredential(_CFURLCredential const*) + 117
    frame #17: 0x00bfa4ce CFNetwork`URLConnectionLoader::LoaderConnectionEventQueue::processAllEventsAndConsumePayload(XConnectionEventInfo<XLoaderEvent, XLoaderEventParams>*, long) + 140
    frame #18: 0x00b228b7 CFNetwork`URLConnectionLoader::processEvents() + 107
    frame #19: 0x00bf716b CFNetwork`non-virtual thunk to URLConnectionInstanceData::multiplexerClientPerform() + 21
    frame #20: 0x00b21137 CFNetwork`MultiplexerSource::perform() + 259
    frame #21: 0x0045e97f CoreFoundation`__CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 15
    frame #22: 0x003c1b73 CoreFoundation`__CFRunLoopDoSources0 + 243
    frame #23: 0x003c1454 CoreFoundation`__CFRunLoopRun + 1012
    frame #24: 0x003c0db4 CoreFoundation`CFRunLoopRunSpecific + 212
    frame #25: 0x003c0ccb CoreFoundation`CFRunLoopRunInMode + 123
    frame #26: 0x00108e40 Foundation`+[NSURLConnection(Loader) _resourceLoadLoop:] + 398
    frame #27: 0x0001a4e6 Foundation`-[NSThread main] + 76
    frame #28: 0x0001a457 Foundation`__NSThread__main__ + 1258
    frame #29: 0x94d8fed9 libsystem_c.dylib`_pthread_start + 335

Answer 1

The problem seems to have resolved itself through some combination of iOS 5.1, Xcode 4.3.1 and AppCode 1.5.15 EAP.