It crashes on MKCertificate *cert = [[conn peerCertificates] objectAtIndex:0];

[fbartolom]

When running both the stand-alone app or embedding the library in another project, it crashes in - (void) connection:(MKConnection *)conn trustFailureInCertificateChain:(NSArray *)chain when it tries to take the first object of [conn peerCertificates] as the function returns nil. I peeped inside the function:

// Returns the certificates of the peer of connection. That is, the server's certificate chain.

• (NSArray *) peerCertificates {
  if (_peerCertificates != nil) {
  return _peerCertificates;
  }
  NSArray *secCerts = (NSArray *) CFWriteStreamCopyProperty((CFWriteStreamRef) _outputStream, kCFStreamSocketSecurityLevelSSLv3);
  _peerCertificates = [[NSMutableArray alloc] initWithCapacity:[secCerts count]];
  [secCerts enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
  NSData *data = (NSData *) SecCertificateCopyData((SecCertificateRef)obj);
  [_peerCertificates addObject:[MKCertificate certificateWithCertificate:data privateKey:nil]];
  [data release];
  }];
  [secCerts release];

  return _peerCertificates;
  }
  and I noticed it not even entered the enumeration.

[fbartolom]

As a matter of fact it was due to an attempt to remove the warning on kCFStreamPropertySSLPeerCertificates. Apparently the value I used was not the correct one. What should one employ instead.