upload android base code part8
This commit is contained in:
August
parent
841ae54672
commit
5425409085
57075 changed files with 9846578 additions and 0 deletions
265
android/docs/source.android.com/en/security/index.html
Normal file
265
android/docs/source.android.com/en/security/index.html
Normal file
|
|
@ -0,0 +1,265 @@
|
|||
<html devsite>
|
||||
<head>
|
||||
<title>Security</title>
|
||||
<meta name="project_path" value="/_project.yaml" />
|
||||
<meta name="book_path" value="/_book.yaml" />
|
||||
</head>
|
||||
<body>
|
||||
<!--
|
||||
Copyright 2017 The Android Open Source Project
|
||||
|
||||
Licensed under the Apache License, Version 2.0 (the "License");
|
||||
you may not use this file except in compliance with the License.
|
||||
You may obtain a copy of the License at
|
||||
|
||||
http://www.apache.org/licenses/LICENSE-2.0
|
||||
|
||||
Unless required by applicable law or agreed to in writing, software
|
||||
distributed under the License is distributed on an "AS IS" BASIS,
|
||||
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
See the License for the specific language governing permissions and
|
||||
limitations under the License.
|
||||
-->
|
||||
|
||||
|
||||
|
||||
<p>
|
||||
Android incorporates industry-leading security features and works with
|
||||
developers and device implementers to keep the Android platform and ecosystem
|
||||
safe. A robust security model is essential to enable a vigorous ecosystem of
|
||||
applications and devices built on and around the Android platform and supported
|
||||
by cloud services. As a result, through its entire development lifecycle,
|
||||
Android has been subject to a rigorous security program.
|
||||
</p>
|
||||
<p>
|
||||
<strong>Android is designed to be open</strong>. Android applications use
|
||||
advanced hardware and software, as well as local and served data, exposed
|
||||
through the platform to bring innovation and value to consumers. To realize that
|
||||
value, the platform offers an application environment that protects the
|
||||
confidentiality, integrity, and availability of users, data, applications, the
|
||||
device, and the network.
|
||||
</p>
|
||||
<p>
|
||||
Securing an open platform requires a strong security architecture and rigorous
|
||||
security programs. Android was designed with multi-layered security that is
|
||||
flexible enough to support an open platform while still protecting all users of
|
||||
the platform. For information about reporting security issues and the update
|
||||
process, see <a href="/security/overview/updates-resources.html">Security
|
||||
Updates and Resources</a>.
|
||||
</p>
|
||||
<p>
|
||||
<strong>Android is designed for developers</strong>. Security controls were
|
||||
designed to reduce the burden on developers. Security-savvy developers can
|
||||
easily work with and rely on flexible security controls. Developers less
|
||||
familiar with security will be protected by safe defaults.
|
||||
</p>
|
||||
<p>
|
||||
In addition to providing a stable platform to build upon, Android gives
|
||||
additional support to developers in a number of ways. The Android security team
|
||||
looks for potential vulnerabilities in apps and suggests ways to fix those
|
||||
issues. For devices with Google Play, Play Services delivers security updates
|
||||
for critical software libraries, such as OpenSSL, which is used to secure
|
||||
application communications. Android security released a tool for testing SSL
|
||||
(<a href="https://github.com/google/nogotofail">nogotofail</a>) that helps
|
||||
developers find potential security issues on whichever platform they are
|
||||
developing.
|
||||
</p>
|
||||
<p>
|
||||
More information for Android app developers can be found on
|
||||
<a href="https://developer.android.com/training/best-security.html">developer.android.com</a>.
|
||||
</p>
|
||||
<p>
|
||||
<strong>Android is designed for users</strong>. Users are provided visibility
|
||||
into permissions requested by each application and control over those
|
||||
permissions. This design includes the expectation that attackers would attempt
|
||||
to perform common attacks, such as social engineering attacks to convince device
|
||||
users to install malware, and attacks on third-party applications on Android.
|
||||
Android was designed to both reduce the probability of these attacks and greatly
|
||||
limit the impact of the attack in the event it was successful. Android security
|
||||
continues to progress once the device is in the user's hands: Android works with
|
||||
<a href="/security/overview/acknowledgements.html">partners and the
|
||||
public</a> to provide patches for any Android device that is continuing to
|
||||
receive security updates.
|
||||
</p>
|
||||
<p>
|
||||
More information for end users can be found in the <a
|
||||
href="https://support.google.com/nexus/answer/6172890">Nexus help center</a>,
|
||||
<a href="https://support.google.com/pixelphone/answer/6172890">Pixel help center</a>,
|
||||
or your device manufacturer’s help center.
|
||||
</p>
|
||||
<p>
|
||||
This documentation outlines the goals of the Android security program, describes
|
||||
the fundamentals of the Android security architecture, and answers the most
|
||||
pertinent questions for system architects and security analysts. It focuses on
|
||||
the security features of Android's core platform and does not discuss security
|
||||
issues that are unique to specific applications, such as those related to the
|
||||
browser or SMS application.
|
||||
</p>
|
||||
|
||||
<h2 id="background">Background</h2>
|
||||
<p>
|
||||
Android provides an open source platform and application environment for mobile
|
||||
devices.
|
||||
</p>
|
||||
<p>
|
||||
The sections and pages below describe the security features of the Android
|
||||
platform. <em>Figure 1</em> summarizes the security components and
|
||||
considerations of the various levels of the Android software stack. Each
|
||||
component assumes that the components below are properly secured. With the
|
||||
exception of a small amount of Android OS code running as root, all code above
|
||||
the Linux Kernel is restricted by the Application Sandbox.
|
||||
</p>
|
||||
|
||||
<p><img alt="Figure 1: Android software stack" src="images/android_software_stack.png" /></p>
|
||||
<p class="img-caption">
|
||||
<strong>Figure 1</strong>. Android software stack.
|
||||
</p>
|
||||
<p>
|
||||
The main Android platform building blocks are:
|
||||
</p>
|
||||
<ul>
|
||||
<li><strong>Device hardware</strong>: Android runs on a wide range of hardware
|
||||
configurations including smart phones, tablets, watches, automobiles, smart TVs,
|
||||
OTT gaming boxes, and set-top-boxes. Android is processor-agnostic, but it does
|
||||
take advantage of some hardware-specific security capabilities such as ARM
|
||||
eXecute-Never.</li>
|
||||
<li><strong>Android operating system</strong>: The core operating system is
|
||||
built on top of the Linux kernel. All device resources, like camera functions,
|
||||
GPS data, Bluetooth functions, telephony functions, network connections, etc.
|
||||
are accessed through the operating system.</li>
|
||||
<li><strong>Android Application Runtime</strong>: Android applications are most
|
||||
often written in the Java programming language and run in the Android runtime
|
||||
(ART). However, many applications, including core Android services and
|
||||
applications, are native applications or include native libraries. Both ART and
|
||||
native applications run within the same security environment, contained within
|
||||
the Application Sandbox. Applications get a dedicated part of the filesystem in
|
||||
which they can write private data, including databases and raw files.</li>
|
||||
</ul>
|
||||
<p>
|
||||
Android applications extend the core Android operating system. There are two
|
||||
primary sources for applications:
|
||||
</p>
|
||||
<ul>
|
||||
<li><strong>Pre-installed applications</strong>: Android includes a set of
|
||||
pre-installed applications including phone, email, calendar, web browser, and
|
||||
contacts. These function both as user applications and to provide key device
|
||||
capabilities that can be accessed by other applications. Pre-installed
|
||||
applications may be part of the open source Android platform, or they may be
|
||||
developed by a device manufacturer for a specific device.</li>
|
||||
<li><strong>User-installed applications</strong>: Android provides an open
|
||||
development environment that supports any third-party application. Google Play
|
||||
offers users hundreds of thousands of applications.</li>
|
||||
</ul>
|
||||
|
||||
<h2 id="google-security-services">Google security services</h2>
|
||||
<p>
|
||||
Google provides a set of cloud-based services that are available to compatible
|
||||
Android devices with <a href="https://www.android.com/gms/">Google Mobile
|
||||
Services</a>. While these services are not part of the Android Open Source
|
||||
Project, they are included on many Android devices. For more information on
|
||||
some of these services, see Android Security’s
|
||||
<a href="/security/reports/Google_Android_Security_2015_Report_Final.pdf">2015
|
||||
Year in Review</a>.
|
||||
</p>
|
||||
<p>
|
||||
The primary Google security services are:
|
||||
</p>
|
||||
<ul>
|
||||
<li><strong>Google Play</strong>: Google Play is a collection of services that
|
||||
allow users to discover, install, and purchase applications from their Android
|
||||
device or the web. Google Play makes it easy for developers to reach Android
|
||||
users and potential customers. Google Play also provides community review,
|
||||
application
|
||||
<a href="https://developer.android.com/guide/publishing/licensing.html">license
|
||||
verification</a>, application security scanning, and other security services.</li>
|
||||
<li><strong>Android updates</strong>: The Android update service delivers new
|
||||
capabilities and security updates to selected Android devices, including updates
|
||||
through the web or over the air (OTA).</li>
|
||||
<li><strong>Application services</strong>: Frameworks that allow Android
|
||||
applications to use cloud capabilities such as (<a
|
||||
href="https://developer.android.com/guide/topics/data/backup.html">backing
|
||||
up</a>) application data and settings and cloud-to-device messaging
|
||||
(<a href="https://developers.google.com/cloud-messaging/">C2DM</a>) for push
|
||||
messaging.</li>
|
||||
<li><strong>Verify Apps</strong>: Warn or automatically block the installation
|
||||
of harmful applications, and continually scan applications on the device,
|
||||
warning about or removing
|
||||
<a href="https://support.google.com/accounts/answer/2812853">harmful apps</a>.
|
||||
</li>
|
||||
<li><strong>SafetyNet</strong>: A privacy preserving intrusion detection system
|
||||
to assist Google tracking and mitigating known security threats in addition to
|
||||
identifying new security threats.</li>
|
||||
<li><strong>SafetyNet Attestation</strong>: Third-party API to determine
|
||||
whether the device is CTS compatible. <a
|
||||
href="http://developer.android.com/training/safetynet/index.html">Attestation</a>
|
||||
can also assist identify the Android app communicating with the app server.</li>
|
||||
<li><strong>Android Device Manager</strong>: A
|
||||
<a href="https://www.google.com/android/devicemanager">web app</a> and
|
||||
<a href="https://play.google.com/store/apps/details?id=com.google.android.apps.adm">Android
|
||||
app</a> to locate lost or stolen device.</li>
|
||||
</ul>
|
||||
|
||||
<h2 id="security-program-overview">Security program overview</h2>
|
||||
<p>
|
||||
The key components of the Android Security Program include:
|
||||
</p>
|
||||
<ul>
|
||||
<li><strong>Design review</strong>: The Android security process begins early in
|
||||
the development lifecycle with the creation of a rich and configurable security
|
||||
model and design. Each major feature of the platform is reviewed by engineering
|
||||
and security resources, with appropriate security controls integrated into the
|
||||
architecture of the system.</li>
|
||||
<li><strong>Penetration testing and code review</strong>: During the development
|
||||
of the platform, Android-created and open source components are subject to
|
||||
vigorous security reviews. These reviews are performed by the Android Security
|
||||
Team, Google’s Information Security Engineering team, and independent security
|
||||
consultants. The goal of these reviews is to identify weaknesses and possible
|
||||
vulnerabilities well before major releases, and to simulate the types of
|
||||
analysis that will be performed by external security experts upon release.</li>
|
||||
<li><strong>Open source and community review</strong>: The Android Open Source
|
||||
Project enables broad security review by any interested party. Android also uses
|
||||
open source technologies that have undergone significant external security
|
||||
review, such as the Linux kernel. Google Play provides a forum for users and
|
||||
companies to provide information about specific applications directly to users.</li>
|
||||
<li><strong>Incident Response</strong>: Even with all of these precautions,
|
||||
security issues may occur after shipping, which is why the Android project has
|
||||
created a comprehensive security response process. Full-time Android security
|
||||
team members monitor Android-specific and the general security community for
|
||||
discussion of potential vulnerabilities and review
|
||||
<a href="/security/overview/updates-resources.html#android_security_bug_lifecycle">security
|
||||
bugs</a> filed on the Android bug database. Upon the discovery of legitimate
|
||||
issues, the Android team has a response process that enables the rapid
|
||||
mitigation of vulnerabilities to ensure that potential risk to all Android users
|
||||
is minimized. These cloud-supported responses can include updating the Android
|
||||
platform (over-the-air updates), removing applications from Google Play, and
|
||||
removing applications from devices in the field.</li>
|
||||
<li><strong>Monthly security updates</strong>: The Android security team
|
||||
provides <a href="/security/bulletin/index.html">monthly
|
||||
updates</a> to Google Nexus devices and all of our device manufacturing
|
||||
partners.</li>
|
||||
</ul>
|
||||
|
||||
<h2 id="platform-security-architecture">Platform security architecture</h2>
|
||||
<p>
|
||||
Android seeks to be the most secure and usable operating system for mobile
|
||||
platforms by re-purposing traditional operating system security controls to:
|
||||
</p>
|
||||
<ul>
|
||||
<li>Protect application and user data</li>
|
||||
<li>Protect system resources (including the network)</li>
|
||||
<li>Provide application isolation from the system, other applications, and from
|
||||
the user</li>
|
||||
</ul>
|
||||
<p>
|
||||
To achieve these objectives, Android provides these key security features:
|
||||
</p>
|
||||
<ul>
|
||||
<li>Robust security at the OS level through the Linux kernel</li>
|
||||
<li>Mandatory application sandbox for all applications</li>
|
||||
<li>Secure interprocess communication</li>
|
||||
<li>Application signing</li>
|
||||
<li>Application-defined and user-granted permissions</li>
|
||||
</ul>
|
||||
|
||||
</body>
|
||||
</html>
|
||||
Loading…
Add table
Add a link
Reference in a new issue