/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* 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/. */

/* Defines the abstract interface for a principal. */

#include "nsISerializable.idl"

%{C++
struct JSContext;
struct JSPrincipals;
%}

interface nsIURI;
interface nsIContentSecurityPolicy;

[ptr] native JSContext(JSContext);
[ptr] native JSPrincipals(JSPrincipals);

[scriptable, uuid(42ba6a38-d619-49ab-8248-3d247e959d5e)]
interface nsIPrincipal : nsISerializable
{
    /**
     * Values of capabilities for each principal. Order is
     * significant: if an operation is performed on a set
     * of capabilities, the minimum is computed.
     */
    const short ENABLE_DENIED                = 1;
    const short ENABLE_UNKNOWN               = 2;
    const short ENABLE_WITH_USER_PERMISSION  = 3;
    const short ENABLE_GRANTED               = 4;

    /**
     * Returns the security preferences associated with this principal.
     * prefBranch will be set to the pref branch to which these preferences
     * pertain.  id is a pseudo-unique identifier, pertaining to either the
     * fingerprint or the origin.  subjectName is a name that identifies the
     * entity this principal represents (may be empty).  grantedList and
     * deniedList are space-separated lists of capabilities which were
     * explicitly granted or denied by a pref.  isTrusted is a boolean that
     * indicates whether this is a codebaseTrusted certificate.
     */
    void getPreferences(out string prefBranch, out string id,
                        out string subjectName, out string grantedList,
                        out string deniedList, out boolean isTrusted);

    /**
     * Returns whether the other principal is equivalent to this principal.
     * Principals are considered equal if they are the same principal,
     * they have the same origin, or have the same certificate fingerprint ID
     */
    boolean equals(in nsIPrincipal other);

    /**
     * Like equals, but doesn't take document.domain changes into account.
     */
    boolean equalsIgnoringDomain(in nsIPrincipal other);

    /**
     * Returns a hash value for the principal.
     */
    [noscript] readonly attribute unsigned long hashValue;

    /**
     * The domain security policy of the principal.
     */
    // XXXcaa should this be here?  The script security manager is the only
    // thing that should care about this.  Wouldn't storing this data in one
    // of the hashtables in nsScriptSecurityManager be better?
    // XXXbz why is this writable?  Who should have write access to this?  What
    // happens if this principal is in our hashtable and we pass it out of the
    // security manager and someone writes to this field?  Especially if they
    // write garbage?  If we need to give someone other than the security
    // manager a way to set this (which I question, since it can increase the
    // permissions of a page) it should be a |void clearSecurityPolicy()|
    // method.
    [noscript] attribute voidPtr securityPolicy;

    // XXXcaa probably should be turned into {get|set}CapabilityFlags
    // XXXbz again, what if this lives in our hashtable and someone
    // messes with it?  Is that OK?
    [noscript] short canEnableCapability(in string capability);
    [noscript] boolean isCapabilityEnabled(in string capability,
                                           in voidPtr annotation);
    [noscript] void enableCapability(in string capability,
                                     inout voidPtr annotation);
    /**
     * The codebase URI to which this principal pertains.  This is
     * generally the document URI.
     */
    readonly attribute nsIURI URI;

    /**
     * The domain URI to which this principal pertains.
     * This is congruent with HTMLDocument.domain, and may be null.
     * Setting this has no effect on the URI.
     */
    [noscript] attribute nsIURI domain;

    /**
     * The origin of this principal's codebase URI.
     * An origin is defined as: scheme + host + port.
     */
    // XXXcaa this should probably be turned into an nsIURI.
    // The system principal's origin should be some caps namespace
    // with a chrome URI.  All of chrome should probably be the same.
    readonly attribute string origin;

    /**
     * Whether this principal is associated with a certificate.
     */
    readonly attribute boolean hasCertificate;

    /**
     * The fingerprint ID of this principal's certificate.
     * Throws if there is no certificate associated with this principal.
     */
    // XXXcaa kaie says this may not be unique.  We should probably
    // consider using something else for this....
    readonly attribute AUTF8String fingerprint;

    /**
     * The pretty name for the certificate.  This sort of (but not really)
     * identifies the subject of the certificate (the entity that stands behind
     * the certificate).  Note that this may be empty; prefer to get the
     * certificate itself and get this information from it, since that may
     * provide more information.
     *
     * Throws if there is no certificate associated with this principal.
     */
    readonly attribute AUTF8String prettyName;

    /**
     * Returns whether the other principal is equal to or weaker than this
     * principal.  Principals are equal if they are the same object, they
     * have the same origin, or they have the same certificate ID.
     *
     * Thus a principal always subsumes itself.
     *
     * The system principal subsumes itself and all other principals.
     *
     * A null principal (corresponding to an unknown, hence assumed minimally
     * privileged, security context) is not equal to any other principal
     * (including other null principals), and therefore does not subsume
     * anything but itself.
     *
     * Both codebase and certificate principals are subsumed by the system
     * principal, but no codebase or certificate principal yet subsumes any
     * other codebase or certificate principal.  This may change in a future
     * release; note that nsIPrincipal is unfrozen, not slated to be frozen.
     *
     * XXXbz except see bug 147145!
     *
     * Note for the future: Perhaps we should consider a certificate principal
     * for a given URI subsuming a codebase principal for the same URI?  Not
     * sure what the immediate benefit would be, but I think the setup could
     * make some code (e.g. MaybeDowngradeToCodebase) clearer.
     */
    boolean subsumes(in nsIPrincipal other);

    /**
     * Same as the previous method, subsumes(), but for codebase principals
     * ignores changes to document.domain.
     */
    boolean subsumesIgnoringDomain(in nsIPrincipal other);

    /**
     * Checks whether this principal is allowed to load the network resource
     * located at the given URI under the same-origin policy. This means that
     * codebase principals are only allowed to load resources from the same
     * domain, the system principal is allowed to load anything, and null
     * principals are not allowed to load anything.
     *
     * If the load is allowed this function does nothing. If the load is not
     * allowed the function throws NS_ERROR_DOM_BAD_URI.
     *
     * NOTE: Other policies might override this, such as the Access-Control
     *       specification.
     * NOTE: The 'domain' attribute has no effect on the behaviour of this
     *       function.
     *
     *
     * @param uri    The URI about to be loaded.
     * @param report If true, will report a warning to the console service
     *               if the load is not allowed.
     * @throws NS_ERROR_DOM_BAD_URI if the load is not allowed.
     */
    void checkMayLoad(in nsIURI uri, in boolean report);

    /**
     * The subject name for the certificate.  This actually identifies the
     * subject of the certificate.  This may well not be a string that would
     * mean much to a typical user on its own (e.g. it may have a number of
     * different names all concatenated together with some information on what
     * they mean in between).
     *
     * Throws if there is no certificate associated with this principal.
     */
    readonly attribute AUTF8String subjectName;

    /**
     * The certificate associated with this principal, if any.  If there isn't
     * one, this will return null.  Getting this attribute never throws.
     */
    readonly attribute nsISupports certificate;

    /**
     * A Content Security Policy associated with this principal.
     */
    [noscript] attribute nsIContentSecurityPolicy csp;
};
