/*
 * Copyright (C) 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
 * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
 * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer. 
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution. 
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"
#include "PolicyChecker.h"

#include "ContentSecurityPolicy.h"
#include "DocumentLoader.h"
#include "FormState.h"
#include "Frame.h"
#include "FrameLoader.h"
#include "FrameLoaderClient.h"
#include "HTMLFormElement.h"
#include "HTMLFrameOwnerElement.h"
#include "HTMLPlugInElement.h"
#include "SecurityOrigin.h"

namespace WebCore {

static bool isAllowedByContentSecurityPolicy(const KURL& url, const Element* ownerElement, bool didReceiveRedirectResponse)
{
    if (!ownerElement)
        return true;
    auto redirectResponseReceived = didReceiveRedirectResponse ? ContentSecurityPolicy::RedirectResponseReceived::Yes : ContentSecurityPolicy::RedirectResponseReceived::No;
	if (ownerElement->isPluginElement())
        return ownerElement->document()->contentSecurityPolicy()->allowObjectFromSource(url, ownerElement->isInUserAgentShadowTree(), redirectResponseReceived);
    return ownerElement->document()->contentSecurityPolicy()->allowChildFrameFromSource(url, ownerElement->isInUserAgentShadowTree(), redirectResponseReceived);
}

PolicyChecker::PolicyChecker(Frame* frame)
    : m_frame(frame)
    , m_delegateIsDecidingNavigationPolicy(false)
    , m_delegateIsHandlingUnimplementablePolicy(false)
    , m_loadType(FrameLoadTypeStandard)
{
}

void PolicyChecker::checkNavigationPolicy(const ResourceRequest& newRequest, bool didReceiveRedirectResponse, NavigationPolicyDecisionFunction function, void* argument)
{
    checkNavigationPolicy(newRequest, didReceiveRedirectResponse, m_frame->loader()->activeDocumentLoader(), nullptr, function, argument);
}

void PolicyChecker::checkNavigationPolicy(const ResourceRequest& request, bool didReceiveRedirectResponse, DocumentLoader* loader,
    PassRefPtr<FormState> formState, NavigationPolicyDecisionFunction function, void* argument)
{
    NavigationAction action = loader->triggeringAction();
    if (action.isEmpty()) {
        action = NavigationAction(request, NavigationTypeOther);
        loader->setTriggeringAction(action);
    }

    // Don't ask more than once for the same request or if we are loading an empty URL.
    // This avoids confusion on the part of the client.
    if (equalIgnoringHeaderFields(request, loader->lastCheckedRequest()) || (!request.isNull() && request.url().isEmpty())) {
        function(argument, request, nullptr, true);
        loader->setLastCheckedRequest(request);
        return;
    }
    
    // We are always willing to show alternate content for unreachable URLs;
    // treat it like a reload so it maintains the right state for b/f list.
    if (loader->substituteData().isValid() && !loader->substituteData().failingURL().isEmpty()) {
        if (isBackForwardLoadType(m_loadType))
            m_loadType = FrameLoadTypeReload;
        function(argument, request, nullptr, true);
        return;
    }

    if (!isAllowedByContentSecurityPolicy(request.url(), m_frame->ownerElement(), didReceiveRedirectResponse)) {
    	function(argument, request, nullptr, false);
        return;
    }
    
    loader->setLastCheckedRequest(request);

    m_callback.set(request, formState.get(), function, argument);

    m_delegateIsDecidingNavigationPolicy = true;
    m_suggestedFilename = action.downloadAttribute();
    m_frame->loader()->client()->dispatchDecidePolicyForNavigationAction(&PolicyChecker::continueAfterNavigationPolicy,
        action, request, formState);
    m_delegateIsDecidingNavigationPolicy = false;
}

void PolicyChecker::checkNewWindowPolicy(const NavigationAction& action, NewWindowPolicyDecisionFunction function,
    const ResourceRequest& request, PassRefPtr<FormState> formState, const String& frameName, void* argument)
{
    if (m_frame->document() && m_frame->document()->isSandboxed(SandboxPopups))
        return continueAfterNavigationPolicy(PolicyIgnore);

    m_callback.set(request, formState, frameName, action, function, argument);
    m_frame->loader()->client()->dispatchDecidePolicyForNewWindowAction(&PolicyChecker::continueAfterNewWindowPolicy,
        action, request, formState, frameName);
}

void PolicyChecker::checkContentPolicy(const ResourceResponse& response, ContentPolicyDecisionFunction function, void* argument)
{
    m_callback.set(function, argument);
    m_frame->loader()->client()->dispatchDecidePolicyForResponse(&PolicyChecker::continueAfterContentPolicy,
        response, m_frame->loader()->activeDocumentLoader()->request());
}

void PolicyChecker::cancelCheck()
{
    m_frame->loader()->client()->cancelPolicyCheck();
    m_callback.clear();
}

void PolicyChecker::stopCheck()
{
    m_frame->loader()->client()->cancelPolicyCheck();
    PolicyCallback callback = m_callback;
    m_callback.clear();
    callback.cancel();
}

void PolicyChecker::cannotShowMIMEType(const ResourceResponse& response)
{
    handleUnimplementablePolicy(m_frame->loader()->client()->cannotShowMIMETypeError(response));
}

void PolicyChecker::continueLoadAfterWillSubmitForm(PolicyAction)
{
    // See header file for an explaination of why this function
    // isn't like the others.
    m_frame->loader()->continueLoadAfterWillSubmitForm();
}

void PolicyChecker::continueAfterNavigationPolicy(PolicyAction policy)
{
    PolicyCallback callback = m_callback;
    m_callback.clear();

    bool shouldContinue = policy == PolicyUse;

    switch (policy) {
        case PolicyIgnore:
            callback.clearRequest();
            break;
        case PolicyDownload: {
            ResourceRequest request = callback.request();
            m_frame->loader()->setOriginalURLForDownloadRequest(request);
            m_frame->loader()->client()->startDownload(request);
            callback.clearRequest();
            break;
        }
        case PolicyUse: {
            ResourceRequest request(callback.request());

            if (!m_frame->loader()->client()->canHandleRequest(request)) {
                handleUnimplementablePolicy(m_frame->loader()->client()->cannotShowURLError(callback.request()));
                callback.clearRequest();
                shouldContinue = false;
            }
            break;
        }
    }

    callback.call(shouldContinue);
}

void PolicyChecker::continueAfterNewWindowPolicy(PolicyAction policy)
{
    PolicyCallback callback = m_callback;
    m_callback.clear();

    switch (policy) {
        case PolicyIgnore:
            callback.clearRequest();
            break;
        case PolicyDownload:
            m_frame->loader()->client()->startDownload(callback.request(), m_suggestedFilename);
            callback.clearRequest();
            break;
        case PolicyUse:
            break;
    }

    callback.call(policy == PolicyUse);
}

void PolicyChecker::continueAfterContentPolicy(PolicyAction policy)
{
    PolicyCallback callback = m_callback;
    m_callback.clear();
    callback.call(policy);
}

void PolicyChecker::handleUnimplementablePolicy(const ResourceError& error)
{
    m_delegateIsHandlingUnimplementablePolicy = true;
    m_frame->loader()->client()->dispatchUnableToImplementPolicy(error);
    m_delegateIsHandlingUnimplementablePolicy = false;
}

} // namespace WebCore
