/*

 * Copyright (C) 2007,2008 Apple Inc. All rights reserved.

 *

 * 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;

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 */

#ifndef SecurityOrigin_h

#define SecurityOrigin_h

#include <wtf/HashSet.h>

#include <wtf/RefCounted.h>

#include <wtf/PassRefPtr.h>

#include <wtf/Threading.h>

#include "PlatformString.h"

#include "StringHash.h"

namespace WebCore {

    typedef HashSet<String, CaseFoldingHash> URLSchemesMap;

    class Document;

    class KURL;

    class SecurityOrigin : public ThreadSafeShared<SecurityOrigin> {

    public:

        static PassRefPtr<SecurityOrigin> createFromDatabaseIdentifier(const String&);

        static PassRefPtr<SecurityOrigin> createFromString(const String&);

        static PassRefPtr<SecurityOrigin> create(const KURL&);

        static PassRefPtr<SecurityOrigin> createEmpty();

        // Create a deep copy of this SecurityOrigin.  This method is useful

        // when marshalling a SecurityOrigin to another thread.

        PassRefPtr<SecurityOrigin> threadsafeCopy();

        // Set the domain property of this security origin to newDomain.  This

        // function does not check whether newDomain is a suffix of the current

        // domain.  The caller is responsible for validating newDomain.

        void setDomainFromDOM(const String& newDomain);

        bool domainWasSetInDOM() const { return m_domainWasSetInDOM; }

        String protocol() const { return m_protocol; }

        String host() const { return m_host; }

        String domain() const { return m_domain; }

        unsigned short port() const { return m_port; }

        // Returns true if this SecurityOrigin can script objects in the given

        // SecurityOrigin.  For example, call this function before allowing

        // script from one security origin to read or write objects from

        // another SecurityOrigin.

        bool canAccess(const SecurityOrigin*) const;

        // Returns true if this SecurityOrigin can read content retrieved from

        // the given URL.  For example, call this function before issuing

        // XMLHttpRequests.

        bool canRequest(const KURL&) const;

        // Returns true if drawing an image from this URL taints a canvas from

        // this security origin.  For example, call this function before

        // drawing an image onto an HTML canvas element with the drawImage API.

        bool taintsCanvas(const KURL&) const;

        // Returns true for any non-local URL. If document parameter is supplied,

        // its local load policy dictates, otherwise if referrer is non-empty and

        // represents a local file, then the local load is allowed.

        static bool canLoad(const KURL&, const String& referrer, Document* document);

        // Returns true if this SecurityOrigin can load local resources, such

        // as images, iframes, and style sheets, and can link to local URLs.

        // For example, call this function before creating an iframe to a

        // file:// URL.

        //

        // Note: A SecurityOrigin might be allowed to load local resources

        //       without being able to issue an XMLHttpRequest for a local URL.

        //       To determine whether the SecurityOrigin can issue an

        //       XMLHttpRequest for a URL, call canRequest(url).

        bool canLoadLocalResources() const { return m_canLoadLocalResources; }

        // Explicitly grant the ability to load local resources to this

        // SecurityOrigin.

        //

        // Note: This method exists only to support backwards compatibility

        //       with older versions of WebKit.

        void grantLoadLocalResources();

        // Explicitly grant the ability to access very other SecurityOrigin.

        //

        // WARNING: This is an extremely powerful ability.  Use with caution!

        void grantUniversalAccess();

        bool isSecureTransitionTo(const KURL&) const;

        // The local SecurityOrigin is the most privileged SecurityOrigin.

        // The local SecurityOrigin can script any document, navigate to local

        // resources, and can set arbitrary headers on XMLHttpRequests.

        bool isLocal() const;

        // The empty SecurityOrigin is the least privileged SecurityOrigin.

        bool isEmpty() const;

        // Convert this SecurityOrigin into a string.  The string

        // representation of a SecurityOrigin is similar to a URL, except it

        // lacks a path component.  The string representation does not encode

        // the value of the SecurityOrigin's domain property.  The empty

        // SecurityOrigin is represented with the string "null".

        String toString() const;

        // Serialize the security origin to a string that could be used as part of

        // file names. This format should be used in storage APIs only.

        String databaseIdentifier() const;

        // This method checks for equality between SecurityOrigins, not whether

        // one origin can access another.  It is used for hash table keys.

        // For access checks, use canAccess().

        // FIXME: If this method is really only useful for hash table keys, it

        // should be refactored into SecurityOriginHash.

        bool equal(const SecurityOrigin*) const;

        // This method checks for equality, ignoring the value of document.domain

        // (and whether it was set) but considering the host. It is used for postMessage.

        bool isSameSchemeHostPort(const SecurityOrigin*) const;

        static void registerURLSchemeAsLocal(const String&);

        static void removeURLSchemeRegisteredAsLocal(const String&);

        static const URLSchemesMap& localURLSchemes();

        static bool shouldTreatURLAsLocal(const String&);

        static bool shouldTreatURLSchemeAsLocal(const String&);

        static bool shouldHideReferrer(const KURL&, const String& referrer);

        enum LocalLoadPolicy {

            AllowLocalLoadsForAll,  // No restriction on local loads.

            AllowLocalLoadsForLocalAndSubstituteData,

            AllowLocalLoadsForLocalOnly,

        };

        static void setLocalLoadPolicy(LocalLoadPolicy);

        static bool restrictAccessToLocal();

        static bool allowSubstituteDataAccessToLocal();

        static void registerURLSchemeAsNoAccess(const String&);

        static bool shouldTreatURLSchemeAsNoAccess(const String&);

        static void whiteListAccessFromOrigin(const SecurityOrigin& sourceOrigin, const String& destinationProtocol, const String& destinationDomains, bool allowDestinationSubdomains);

        static void resetOriginAccessWhiteLists();

        static bool isDefaultPortForProtocol(unsigned short port, const String& protocol);

    private:

        explicit SecurityOrigin(const KURL&);

        explicit SecurityOrigin(const SecurityOrigin*);

        String m_protocol;

        String m_host;

        String m_domain;

        unsigned short m_port;

        bool m_noAccess;

        bool m_universalAccess;

        bool m_domainWasSetInDOM;

        bool m_canLoadLocalResources;

    };

} // namespace WebCore

#endif // SecurityOrigin_h