谷歌“新宠” Rust

{"type":"doc","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"近日，谷歌宣布 Android 开源项目（AOSP）现已支持使用 Rust 编程语言来开发 OS。这一举动让正火的 Rust 语言热度再次上涨。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"要用 Rust 解决什么问题？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"目前，Android项目主要用两种语言构建。Java(以及最近出现的与jvm兼容的语言，如Kotlin)已被用于操作系统的上层部分，如UI部分；在内核、驱动程序等 OS 的基础层面，则通常用C编写，有时也会使用C++。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"为了更适合OS的底层编程，这些语言在设计时，考虑到了可控和可预测性等特性，可以提供对底层系统资源和硬件的访问。同时，它们的资源需求相对轻量，可预测性更强。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"因此，C语言，甚至C++，都被认为非常适用于系统级编程，因为它们某种程度上提供了接近底层硬件的功能，这是一些高级语言都很难实现的。"}]},{"type":"image","attrs":{"src":"https:\/\/static001.geekbang.org\/infoq\/0d\/0d55ae9feefe1419dc5e8a37ae4c6aca.png","alt":null,"title":null,"style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":null,"fromPaste":true,"pastePass":true}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"但这种灵活性是一把双刃剑。目前，C 和 C++ 的内存安全问题仍然很难解决。由于没有可依赖的垃圾收集，看似简单的内存管理，经常导致严重的安全问题，如缓冲区溢出等。有分析指出，内存安全漏洞占Android开源项目中发现的所有严重安全漏洞的70%。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"Rust 由 Mozilla 推出，最初是被设计为C和C++更安全的替代语言。尽管Rust并没有被广泛用于应用开发，但它已经迅速成为最受青睐的系统开发语言之一。Rust不像C那样依赖手动内存管理，但也缺少带有Java风格的垃圾收集器。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"谷歌方面认为，Rust 使用编译时检查（强制执行对象生命周期 \/ 所有权）和运行时检查（确保内存访问有效）的组合来提供内存安全保证。提供这种安全性的同时，Rust 的性能表现足以匹敌 C 和 C++。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"除了Rust 编程语言的安全性能外，谷歌认为使用Rust 也可以减少成本投入。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"据悉，目前所有 Android 进程均已沙箱化。它们通过遵循“三选二”规则（Rule of 2）来确定功能是否需要额外的隔离和特权。这种规则很简单：给定三个选项，开发人员只能选择以下三个选项中的两个。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https:\/\/static001.geekbang.org\/infoq\/d5\/d5aa78bad467c40c8f1407bb55442c68.png","alt":null,"title":null,"style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":null,"fromPaste":true,"pastePass":true}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"对 Android 来说，这意味着如果代码是用 C\/C++ 编写并解析了不可靠的输入，则应将其放入一个严格受限和无特权的沙箱中。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"虽然这个规则可以有效降低安全漏洞的严重性和暴露程度，但 IPC（进程间通信） 和额外的内存占用，也会使其需要的新进程带来额外的开销并引入延迟。同时，高漏洞密度会降低其有效性，让攻击者可以将多个漏洞连接在一起。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"像 Rust 这样的内存安全语言，可以降低代码中错误的密度，提高当前沙箱的效率，并且可以减少谷歌对沙箱的需求，从而引入更安全、更省资源的新特性。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"Rust的核心理念是所有权。简而言之，每个值都有一个所有者。当该所有者超出范围时，该值将被删除。这限制了基于内存的安全漏洞风险，同时也限制了为确保安全而需要编写的代码数量。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"根据谷歌的分析，大多数内存错误出现在新的或最近修改的代码中，大约 50％的错误出现时间还不到一年。谷歌方面认为，在内存安全语言方面，最好是专注于新开发的代码，而不是重写成熟的 C\/C++ 代码。"}]},{"type":"image","attrs":{"src":"https:\/\/static001.geekbang.org\/infoq\/0b\/0b0c3f5808151f84a4cd6f622c7d0bb7.png","alt":null,"title":null,"style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":null,"fromPaste":true,"pastePass":true}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" “当然，引入一种新的编程语言并不能解决现有 C\/C++ 代码中的错误问题。即便我们重新分配 Android 团队中所有软件工程师的工作，重写几千万行代码也是不可能的。”谷歌表示，旧代码并不是亟需改进的。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"该消息宣布后，一些开发者表示希望可以做NDK，但据Android开发者关系团队的一名成员透露，谷歌目前没有发布Rust NDK的计划，支持应用程序开发的语言将继续是Kotlin、Java、C和C++。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"Rust，谷歌“新宠”"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"在过去的18个月中，谷歌一直在Android开源项目中添加Rust支持，但将Rust扩展到更多的OS会是一个艰巨且耗时很久的项目。除了要维护一些工具链和依赖关系，测试基础设施和工具必须同步更新，开发人员也需要接受培训。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"去年7月，Android平台安全负责人Sudhi Herle表示，将继续在Rust上进行投资，看看哪些系统组件用Rust编写会更好。“我们相信，Rust将最终从根本上让我们所有的用户都能安全地使用这个平台。”"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"目前，Android的新蓝牙堆栈重写代码“ "},{"type":"link","attrs":{"href":"https:\/\/android.googlesource.com\/platform\/system\/bt\/+\/master\/gd\/rust\/","title":null,"type":null},"content":[{"type":"text","text":"Gabeldorsche"}],"marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}]},{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" ”已经使用Rust编写。Gabeldorsche的研发工作始于Android 11，但至今仍未投入使用。Android的Keystore 2.0模块是用Rust编写的，Android的IPC驱动程序binder的用户空间部分也是如此。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"Rust 正在成为谷歌“新宠”，不仅表现在Android开发上。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"今年2月，Rust Core 团队宣布了新成立的 Rust 基金会，创始成员中就包括谷歌。同月，谷歌宣布与 Internet Security Research Group 合作用 Rust 语言重新实现安全组件，包括用 Rust 为 curl 开发 HTTP 和 TLS 后端，为 Apache httpd 项目开发 TLS 库。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"谷歌有望取代Android的全新操作系统Fuchsia的新网络栈也使用了Rust编写。此外，ChromeOS中使用的"},{"type":"link","attrs":{"href":"https:\/\/chromium.googlesource.com\/chromiumos\/platform\/crosvm\/","title":null,"type":null},"content":[{"type":"text","text":"crosvm"}],"marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}]},{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"虚拟机监视器和驱动程序、用于支持FIDO安全密钥的固件等都在使用Rust。谷歌还对Rust开源项目"},{"type":"link","attrs":{"href":"https:\/\/www.mercurial-scm.org\/wiki\/OxidationPlan","title":null,"type":null},"content":[{"type":"text","text":"Mercurial"}],"marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}]},{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"的控制系统也作出了贡献。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"谷歌高级软件工程师兼 Rust 核心团队成员Manish Goregaokar 表示，谷歌选择 Rust 语言，部分原因是它能够与其他语言轻松集成。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"过去几个月，谷歌、Amazon、Facebook、微软以及等科技巨头正疯狂吸纳人才市场上的 Rust 语言程序员，各方都在着力筹备组建 Rust 团队。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"去年 8 月的一轮裁员之后，Mozilla 遣散了约 250 名员工，其中包括不少原 Rust 团队的活跃开发人员，谷歌聘请了此轮裁员中的 Mozilla 前员工 Lars Bergstrom担任工程技术总监。Goregaokar 也来自Mozilla，他目前主要任务是构建一套国际化 Rust 库，并有意继续在该语言的开源项目开发中投入精力。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"开发者表示欢迎"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"对于谷歌的这一决定，很多开发者表示很兴奋。在"},{"type":"link","attrs":{"href":"https:\/\/news.ycombinator.com\/news","title":null,"type":null},"content":[{"type":"text","text":"Hacker News"}],"marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}]},{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"上，一位开发者留言表示："}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"我很高兴看到Rust在越来越多的项目中发挥作用。我在几周前开始学习，感觉与C++相比，Rust 更加简单，快速，它有一个熟悉的注册表。它适用于嵌入式、web,、Wasm、一些快速脚本，CLIs。我的背景主要是JavaScript、Dart和Java，但现在我很兴奋地尝试一些更低层次的东西，唯一的问题是我需要找到一种方法过渡到一个好的Rust项目。"}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"另外，也有开发者提出了一个疑问：在Java\/Kotlin应用程序中添加Rust代码，应用程序将不断地在Java和本机代码之间切换，虽然可以但对性能不是很友好。但值得庆幸的是，Chrome和Firefox并没有完全编译成字节码，JIT和渲染代码是用本机代码编写的。Mozilla在浏览器中使用了Rust，这意味着至少Android上已经有一个相当大的Rust运行库了。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":"Kotlin和Java都很棒，在这一点上，开发者们几乎没有什么分歧，但有开发者表示“Java太沉重了，使用Rust会带来新体验。”随着Rust的应用越来越广，已经有开发者讨论，谷歌将来会不会发布一个可以用来写Rust的应用程序。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}},{"type":"strong"}],"text":"参考链接："}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}],"text":" "}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"link","attrs":{"href":"https:\/\/security.googleblog.com\/2021\/04\/rust-in-android-platform.html","title":null,"type":null},"content":[{"type":"text","text":"https:\/\/security.googleblog.com\/2021\/04\/rust-in-android-platform.html"}],"marks":[{"type":"color","attrs":{"color":"#494949","name":"user"}}]}]}]}