UserMediaPermissionRequestManagerProxy.mm   [plain text]

/*
 * Copyright (C) 2020 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.
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 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. 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 INC. OR ITS CONTRIBUTORS
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 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
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#import "config.h"
#import "UserMediaPermissionRequestManagerProxy.h"

#import "SandboxUtilities.h"
#import "TCCSPI.h"
#import "WebPageProxy.h"
#import "WebPreferences.h"
#import <WebCore/RuntimeApplicationChecks.h>
#import <wtf/BlockPtr.h>
#import <wtf/cocoa/RuntimeApplicationChecksCocoa.h>

#import <pal/cocoa/AVFoundationSoftLink.h>
#import <wtf/spi/darwin/SandboxSPI.h>

SOFT_LINK_PRIVATE_FRAMEWORK(TCC)
SOFT_LINK(TCC, TCCAccessPreflight, TCCAccessPreflightResult, (CFStringRef service, CFDictionaryRef options), (service, options))
SOFT_LINK(TCC, TCCAccessPreflightWithAuditToken, TCCAccessPreflightResult, (CFStringRef service, audit_token_t token, CFDictionaryRef options), (service, token, options))
SOFT_LINK_CONSTANT(TCC, kTCCServiceMicrophone, CFStringRef)
SOFT_LINK_CONSTANT(TCC, kTCCServiceCamera, CFStringRef)

namespace WebKit {

bool UserMediaPermissionRequestManagerProxy::permittedToCaptureAudio()
{
#if ENABLE(MEDIA_STREAM)

#if PLATFORM(MAC)
    static std::once_flag onceFlag;
    static bool entitled = true;
    std::call_once(onceFlag, [] {
        if (!currentProcessIsSandboxed())
            return;

        int result = sandbox_check(getpid(), "device-microphone", SANDBOX_FILTER_NONE);
        entitled = !result;
        if (result == -1)
            WTFLogAlways("Error checking 'device-microphone' sandbox access, errno=%ld", (long)errno);
    });
    if (!entitled)
        return false;
#endif // PLATFORM(MAC)

    static TCCAccessPreflightResult access = TCCAccessPreflight(getkTCCServiceMicrophone(), NULL);
    if (access == kTCCAccessPreflightGranted)
        return true;

    static bool isPermitted = dynamic_objc_cast<NSString>(NSBundle.mainBundle.infoDictionary[@"NSMicrophoneUsageDescription"]).length;
    return isPermitted;
#else
    return false;
#endif
}

bool UserMediaPermissionRequestManagerProxy::permittedToCaptureVideo()
{
#if ENABLE(MEDIA_STREAM)

#if PLATFORM(MAC)
    static std::once_flag onceFlag;
    static bool entitled = true;
    std::call_once(onceFlag, [] {
        if (!currentProcessIsSandboxed())
            return;

        int result = sandbox_check(getpid(), "device-camera", SANDBOX_FILTER_NONE);
        entitled = !result;
        if (result == -1)
            WTFLogAlways("Error checking 'device-camera' sandbox access, errno=%ld", (long)errno);
    });
    if (!entitled)
        return false;
#endif // PLATFORM(MAC)

    static TCCAccessPreflightResult access = TCCAccessPreflight(getkTCCServiceCamera(), NULL);
    if (access == kTCCAccessPreflightGranted)
        return true;

    static bool isPermitted = dynamic_objc_cast<NSString>(NSBundle.mainBundle.infoDictionary[@"NSCameraUsageDescription"]).length;
    return isPermitted;
#else
    return false;
#endif
}

#if ENABLE(MEDIA_STREAM)
static void requestAVCaptureAccessForMediaType(CompletionHandler<void(BOOL authorized)>&& completionHandler, AVMediaType type)
{
    auto decisionHandler = makeBlockPtr([completionHandler = WTFMove(completionHandler)](BOOL authorized) mutable {
        if (!isMainThread()) {
            callOnMainThread([completionHandler = WTFMove(completionHandler), authorized]() mutable {
                completionHandler(authorized);
            });
            return;
        }
        completionHandler(authorized);
    });
    [PAL::getAVCaptureDeviceClass() requestAccessForMediaType:type completionHandler:decisionHandler.get()];
}

void UserMediaPermissionRequestManagerProxy::requestSystemValidation(const WebPageProxy& page, UserMediaPermissionRequestProxy& request, CompletionHandler<void(bool)>&& callback)
{
    if (page.preferences().mockCaptureDevicesEnabled()) {
        callback(true);
        return;
    }

    // FIXME: Add TCC entitlement check for screensharing.
    bool requiresAudioCapture = request.requiresAudioCapture();
    bool requiresVideoCapture = request.requiresVideoCapture();

    auto microphoneAuthorizationStatus = !requiresAudioCapture ? AVAuthorizationStatusAuthorized : [PAL::getAVCaptureDeviceClass() authorizationStatusForMediaType:AVMediaTypeAudio];
    if (microphoneAuthorizationStatus == AVAuthorizationStatusDenied || microphoneAuthorizationStatus == AVAuthorizationStatusRestricted) {
        callback(false);
        return;
    }

    auto cameraAuthorizationStatus = !requiresVideoCapture ? AVAuthorizationStatusAuthorized : [PAL::getAVCaptureDeviceClass() authorizationStatusForMediaType:AVMediaTypeVideo];
    if (cameraAuthorizationStatus == AVAuthorizationStatusDenied || cameraAuthorizationStatus == AVAuthorizationStatusRestricted) {
        callback(false);
        return;
    }

    bool requiresVideoTCCPrompt = requiresVideoCapture && cameraAuthorizationStatus == AVAuthorizationStatusNotDetermined;
    auto completionHandler = requiresVideoTCCPrompt ? [request = makeRef(request), callback = WTFMove(callback)](bool isOK) mutable {
        if (!isOK) {
            callback(false);
            return;
        }
        requestAVCaptureAccessForMediaType(WTFMove(callback), AVMediaTypeVideo);
    } : WTFMove(callback);

    bool requiresAudioTCCPrompt = requiresAudioCapture && microphoneAuthorizationStatus == AVAuthorizationStatusNotDetermined;
    if (!requiresAudioTCCPrompt) {
        completionHandler(true);
        return;
    }
    requestAVCaptureAccessForMediaType(WTFMove(completionHandler), AVMediaTypeAudio);
}
#endif // ENABLE(MEDIA_STREAM)

} // namespace WebKit