/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set ts=8 sts=2 et sw=2 tw=80: */

/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef mozilla_dom_ContentVerifier_h

#define mozilla_dom_ContentVerifier_h

#include "nsCOMPtr.h"

#include "nsIContentSignatureVerifier.h"

#include "nsIObserver.h"

#include "nsIStreamListener.h"

#include "nsString.h"

#include "nsTArray.h"

/**

 * Mediator intercepting OnStartRequest in nsHttpChannel, blocks until all

 * data is read from the input stream, verifies the content signature and

 * releases the request to the next listener if the verification is successful.

 * If the verification fails or anything else goes wrong, a

 * NS_ERROR_INVALID_SIGNATURE is thrown.

 */

class ContentVerifier : public nsIStreamListener

                      , public nsIContentSignatureReceiverCallback

{

public:

  NS_DECL_ISUPPORTS

  NS_DECL_NSISTREAMLISTENER

  NS_DECL_NSIREQUESTOBSERVER

  NS_DECL_NSICONTENTSIGNATURERECEIVERCALLBACK

  explicit ContentVerifier(nsIStreamListener* aMediatedListener,

                           nsISupports* aMediatedContext)

    : mNextListener(aMediatedListener)

    , mContextCreated(false)

    , mContentRead(false) {}

  nsresult Init(const nsACString& aContentSignatureHeader, nsIRequest* aRequest,

                nsISupports* aContext);

protected:

  virtual ~ContentVerifier() {}

private:

  void FinishSignature();

  // buffered content to verify

  FallibleTArray<nsCString> mContent;

  // content and next listener for nsIStreamListener

  nsCOMPtr<nsIStreamListener> mNextListener;

  // the verifier

  nsCOMPtr<nsIContentSignatureVerifier> mVerifier;

  // holding a pointer to the content request and context to resume/cancel it

  nsCOMPtr<nsIRequest> mContentRequest;

  nsCOMPtr<nsISupports> mContentContext;

  // Semaphors to indicate that the verifying context was created, the entire

  // content was read resp. The context gets created by ContentSignatureVerifier

  // and mContextCreated is set in the ContextCreated callback. The content is

  // read, i.e. mContentRead is set, when the content OnStopRequest is called.

  bool mContextCreated;

  bool mContentRead;

};

#endif /* mozilla_dom_ContentVerifier_h */