Facebook 的招募狀況

Facebook 的各種醜聞知道招募變難 (而且醜聞沒停過),但變得多困難則是第一次看到報導:「Facebook has struggled to hire talent since the Cambridge Analytica scandal, according to recruiters who worked there」。

新鮮人的接受從 85% 掉到 35%~55%,依據不同的學校而有差異:

Among top schools, Facebook’s acceptance rate for full-time positions offered to new graduates has fallen from an average of 85% for the 2017-2018 school year to between 35% and 55% as of December.

Among top schools, such as Stanford, Carnegie Mellon and Ivy League universities, Facebook’s acceptance rate for full-time positions offered to new graduates has fallen from an average of 85% for the 2017-2018 school year to between 35% and 55% as of December, according to former Facebook recruiters. The biggest decline came from Carnegie Mellon University, where the acceptance rate for new recruits dropped to 35%.

工程師則是從 90% 掉到 50%:

The company has seen a decline in its job offer acceptance rates to software engineer candidates from nearly 90% in late 2016 to almost 50% in early 2019.

Facebook 發言人 Anthony Harrison 否認,不過沒有給出說明:

After the publication of this story, Harrison contacted CNBC to say "these numbers are totally wrong."

Facebook disputed the accuracy of the recruiters' accounts, but declined to point out any specific points that were wrong.

Hacker News 上的討論也蠻有趣的:「https://news.ycombinator.com/item?id=19931977」,有不少其他的觀察。

AWS 香港區開放

Twitter 上看到 AWS 公開了香港區的消息:「Announcing the AWS Asia Pacific (Hong Kong) Region」,他們總算是想起來有這區了:

有三個 AZ:

The AWS Asia Pacific (Hong Kong) Region consists of three Availability Zones and with this launch, the AWS Global Infrastructure now offers 64 Availability Zones worldwide, serving customers in over 190 countries.

不過在 Region Table 裡面還沒出現,雖然上面已經標「Last updated: April 24, 2019」了... 從「AWS Regions and Endpoints」可以看到區域代碼是 ap-east-1,然後可以看到 S3 的部分是這樣寫:

You must enable this Region before you can use it.

加上之前的一些傳言,可以猜測一些事情?

Anyway,本來是說 2018 年的時候要開 (參考 2017 年的「AWS 香港區 2018 開台」這篇),總算在 2019 年開了...

Let's Encrypt 從七月開始將會改用自己的 Root 簽發憑證

Let's Encrypt 宣佈了以後的憑證的簽發計畫:「Transitioning to ISRG's Root」。

主要的改變是 2019/07/08 之後提供的 intermediate CA 會改變,從現在的 cross-sign 變成只有自己的 Root CA:

On July 8, 2019, we will change the default intermediate certificate we provide via ACME. Most subscribers don’t need to do anything. Subscribers who support very old TLS/SSL clients may want to manually configure the older intermediate to increase backwards compatibility.

目前的簽發用的兩個中介憑證 (Let's Encrypt Authority X3Let's Encrypt Authority X4) 是由 Let's Encrypt 自己的 ISRG Root X1IdenTrustDST Root CA X3 所 共同簽署的:

這是因為 IdenTrust 的 DST Root CA X3 憑證很久前就被各家瀏覽器信任 (像是 Mozilla 的「Request to add two additional IdenTrust root CA certificates」這篇,可以看到 2007 年就被放進去了),而 Let's Encrypt 當時為了更快把可用的產品推出,所以跟 IdenTrust 合作,採用 cross sign 的方式讓 Let's Encrypt 簽出來的憑證被一般瀏覽器與函式庫所信任。

現在差不多過了三年半,Let's Encrypt 成為目前世界上最大的 SSL Certificate 發放單位,加上自己的 Root CA (ISRG Root X1) 也都差不多被整合進各家系統內了,所以打算要獨立自己簽了。

不過系統上可以設定,使用者如果有遇到相容性問題 (太舊的系統可能還是不包含 Let's Encrypt 自家的 ISRG Root X1),還是可以設定使用有 cross-sign 的版本 (維持現狀)。與 IdenTrust 的 cross-sign 會維持到 2021 年九月,大約再兩年多一些:

Our current cross-signature from IdenTrust expires on March 17, 2021. The IdenTrust root that we are cross-signed from expires on September 30, 2021. Within the next year we will obtain a new cross-signature that is valid until September 29, 2021. This means that our subscribers will have the option to manually configure a certificate chain that uses IdenTrust until September 29, 2021.

對於自用來說應該沒什麼大影響,主要是企業用戶要注意相容性...

擋廣告的 Pi-hole

Pi-hole 最近愈來愈紅的一個計畫,技術上是透過 DNS 把不想要的網域名稱擋掉,通常就是擋掉各種 tracking 與廣告系統。

因為是透過 DNS 擋,當然沒有像 uBlock Origin 直接 parse 網頁內容來的有效,但對於方便性來說則是大勝,只需要在網路設備上設一次,所有的裝置都可以用到。

剛剛看到「How a Single Raspberry Pi made my Home Network Faster」這篇,可以看到 Pi-hole 有不錯的介面可以看 (讓你自我感覺良好?XD):

文章作者跑了一個月後,也直言還是有些東西會壞掉,需要設定一些白名單讓他動:

Review after 1 month in operation
The Pi-Hole has been running for 1 month now on my home network. I have had to whitelist 1 or 2 URLs which was blocking a reset of an Alexa which had an issue, and a video conferencing system had all sorts of tracking and metrics built in which were causing some havoc until I whitelisted them. Otherwise, the Pi has been chugging along at 8% memory utilization, and the network is considerably faster when surfing the web.

對於手癢自己玩應該還可以,拿到辦公室的話應該會有不少東西掛掉... (不過文章作者好像想這樣做)

Gmail 宣佈支援 MTA-STS

Gmail 宣佈支援 MTA-STS:「Gmail making email more secure with MTA-STS standard」。這邊提到的 MTA-STS 是透過某些設定,讓 SMTP 送信時強制使用 TLS 的機制,可以參考「SMTP 的強加密連線機制」這篇。

可以看到有 TXT,也有 .well-known 檔案:

;; ANSWER SECTION:
_mta-sts.gmail.com.     300     IN      TXT     "v=STSv1; id=20171114T070707;"

$ curl https://mta-sts.gmail.com/.well-known/mta-sts.txt
version: STSv1
mode: testing
mx: gmail-smtp-in.l.google.com
mx: *.gmail-smtp-in.l.google.com
max_age: 86400

如果要自己設定的話可以參考 Google 提供的「About MTA-STS and TLS Reporting」這篇,不過目前中文版文件還沒有更新,請切到英文版...

PHP 終止 mirror 站台計畫

Twitter 上看到的公告:

本來 PHP 開放讓各地區的自願者提供頻寬,使用 PHP 的網域名稱 (像是 tw.php.net 這樣),現在則是全部都收回,由官方統一提供有 HTTPS 的網頁版本 https://www.php.net/

目前看起來 latency 頗高,都是到美東的伺服器上?下載也都還是指在 https://www.php.net/ 上,不知道 CDN 是用在哪裡...

Cloudflare 打算再推出 VPN 服務

去年在四月一日推出 1.1.1.1 服務的 Cloudflare 打算更進一步保護連線內容,提供 Wrap 服務 (就是 VPN):「Introducing Warp: Fixing Mobile Internet Performance and Security」。

不過這樣在 privacy 上的保護就變弱了,因為 Cloudflare 手上就拿到更多流量資訊可以交叉比對... 大概會申請起來放著在外面用,而不會平常就開著。

申請是透過 app 申請,Android 的在「1.1.1.1: Faster & Safer Internet」這邊,而 iOS 的在「1.1.1.1: Faster Internet」這邊。

目前申請後需看到排隊的編號,像是這樣:

FTC 找了七家 ISP 業者要研究隱私問題...

FTC 要研究 ISP 手上有哪些客戶的資料,然後提供給誰:「FTC Seeks to Examine the Privacy Practices of Broadband Providers」。

The Federal Trade Commission issued orders to seven U.S. Internet broadband providers and related entities seeking information the agency will use to examine how broadband companies collect, retain, use, and disclose information about consumers and their devices.

包括了這七家,裡面的六家都算大業者,被 FTC 納入不算意外,第七家包括了 Google Fiber Inc.,到時候不知道會有什麼資訊出來:

The orders were sent to: AT&T Inc., AT&T Mobility LLC, Comcast Cable Communications doing business as Xfinity, Google Fiber Inc., T-Mobile US Inc., Verizon Communications Inc., and Cellco Partnership doing business as Verizon Wireless.

看了一下 PDF,應該是 45 天後要回覆,加上整理的時間,應該是下半年會看到一些整理?

Cloudflare 自己用 Rust 寫了一套相容 WireGuard 協定的軟體

Cloudflare 發現目前符合他們條件的 WireGuard 軟體效能不夠好,所以就用 Rust 寫了一套出來:「BoringTun, a userspace WireGuard implementation in Rust」,軟體在「BoringTun」這邊可以看到。

Cloudflare 的條件是 userspace 以及多平台,市面上有 wireguard-go 符合這兩個條件,但效能不太好,所以就下去寫了。

GitHub 的頁面上可以看出還在剛開始的階段,很多頁面都還只有個雛型... 等這幾天陸陸續續更新後再回來看好了。

Facebook 員工爆料內部密碼存了明碼

Krebs on Security 這邊看到的:「Facebook Stored Hundreds of Millions of User Passwords in Plain Text for Years」,Facebook 官方的回應在「Keeping Passwords Secure」這邊。

幾個重點,第一個是範圍,目前已經有看到 2012 的資料都有在內:

The Facebook source said the investigation so far indicates between 200 million and 600 million Facebook users may have had their account passwords stored in plain text and searchable by more than 20,000 Facebook employees. The source said Facebook is still trying to determine how many passwords were exposed and for how long, but so far the inquiry has uncovered archives with plain text user passwords dating back to 2012.

另外的重點是這些資料已經被內部拿來大量搜尋 (喔喔):

My Facebook insider said access logs showed some 2,000 engineers or developers made approximately nine million internal queries for data elements that contained plain text user passwords.

另外是 Legal 與 PR 都已經啟動處理了,對外新聞稿會美化數字,降低傷害:

“The longer we go into this analysis the more comfortable the legal people [at Facebook] are going with the lower bounds” of affected users, the source said. “Right now they’re working on an effort to reduce that number even more by only counting things we have currently in our data warehouse.”

另外也會淡化後續的程序:

Renfro said the company planned to alert affected Facebook users, but that no password resets would be required.

去年的另外一則新聞可以交叉看:「Facebook’s security chief is leaving, and no one’s going to replace him」:

Instead of building out a dedicated security team, Facebook has dissolved it and is instead embedding security engineers within its other divisions. “We are not naming a new CSO, since earlier this year we embedded our security engineers, analysts, investigators, and other specialists in our product and engineering teams to better address the emerging security threats we face,” a Facebook spokesman said in an email. Facebook will “continue to evaluate what kind of structure works best” to protect users’ security, he said.

看起來又要再換一次密碼了... (還好已經習慣用 Password Manager,所以每個站都有不同密碼?)

喔對,另外補充一個概念,當他們說「我們沒有證據有人存取了...」的時候,比較正確的表達應該是「我們沒有稽核這塊... 所以沒有證據」。