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Hacker News 的潛規則

在「A List of Hacker News's Undocumented Features and Behaviors」這邊列了不少 Hacker News 的潛規則,看過後其實比較重要的是「當你需要自己實做一個類似的系統時,有哪些歷史教訓是人家已經走過的」。

像是 Anti-Voting Manipulation 與 Flame-War Detector 都是蠻常見的情境,Shadowbanning 則是防治廣告機制中比較軟性的一環。Green Usernames 也算是軟性的機制...

另外產品面上,Hacker News 也設計一些常見的 list 讓使用者除了首頁以外的選擇。

GitHub 在 2/28 遭受的攻擊...

GitHub 在 2/28 遭受 DDoS 攻擊,蠻快就把事故報告丟出來了:「February 28th DDoS Incident Report」。

不過跟 GitHub 其他文章不太一樣,這篇算是 PR 稿吧,簡單來說就是花錢買 Akamai Prolexic 的過濾服務解決... Akamai 方的 PR 稿則是在「Memcached-fueled 1.3 Tbps attacks - The Akamai Blog」這邊可以看到。

17:21 UTC 發現問題,然後判斷超過 100Gbps,所以 17:26 決定讓 Akamai Prolexic 接管過濾:

At 17:21 UTC our network monitoring system detected an anomaly in the ratio of ingress to egress traffic and notified the on-call engineer and others in our chat system. This graph shows inbound versus outbound throughput over transit links:

Given the increase in inbound transit bandwidth to over 100Gbps in one of our facilities, the decision was made to move traffic to Akamai, who could help provide additional edge network capacity. At 17:26 UTC the command was initiated via our ChatOps tooling to withdraw BGP announcements over transit providers and announce AS36459 exclusively over our links to Akamai. Routes reconverged in the next few minutes and access control lists mitigated the attack at their border. Monitoring of transit bandwidth levels and load balancer response codes indicated a full recovery at 17:30 UTC. At 17:34 UTC routes to internet exchanges were withdrawn as a follow-up to shift an additional 40Gbps away from our edge.

就這樣而已,完全就是 PR 稿 XDDD

義大利政府的反貪組織用 Tor 的 Onion (Hidden Service) 接受檢舉

在「Italian Anti-Corruption Authority (ANAC) Adopts Onion Services」這邊看到,義大利政府因為法令要求必須保護告密者,而不只是在需要提供身份的階段才保護:

Many national laws (such as Italian Dlgs. 231/2001) require companies to adopt corporate governance structures and risk prevention systems, which can include allowing whistleblowing submissions. However, most whistleblowing laws only protect whistleblowers when their identity is disclosed, which can put the person reporting corruption at risk.

In 2016, the International Standards Organization (ISO) released a new model for organizations setting up and operating anti-bribery management systems, ISO 37001:2016. To meet ISO standards, organizations or companies implementing anti-corruption procedures must allow anonymous reporting, as explicitly indicated in point 8.9 of section C of ISO 37001:2016.

Furthermore, national laws (such as recent Italian 179/2017) require the adoption of IT systems for whistleblowing, leading to the practical integration and use of Tor for its technological anonymity features.

而義大利政府的系統選擇用 Tor 的 Onion (Hidden Service) 提供服務接受檢舉:

To comply with these standards, the Italian Anti-Corruption Authority (ANAC), an administrative watchdog, just launched their national online whistleblowing platform using onion services, giving whistleblowers who come forward a secure way to report illegal activity while protecting their identities.

這使用了 hidden service 的特性,讓伺服器端完全無法得知 client 的位置,對於使用有足夠保護的 browser 來說 (像是 Tor Browser),這可以完全讓 server 端無法得知身份,即使政府的伺服器都入侵也沒辦法知道告密者是誰。

這點頗先進的...

GitHub 的 Gist 要移除匿名發表的功能了...

GitHubGist 變成要註冊使用者才能貼了:「Deprecation notice: Removing anonymous gist creation」。主要的原因也還是因為太多 spam 之類的訊息:

In 30 days, we'll be deprecating anonymous gist creation—a decision we made after a lot of deliberation. Anonymous gists are a handy tool for quickly putting a code snippet online, but as the only way to create anonymous content on GitHub, they also see a large volume of spam. In addition, many people already have a combination of tools authenticated with GitHub that allow them to create gists they own.

預定是 3/19 關閉... 只好繼續貼 Pastebin 了... XD

nginx 的 HTTP/2 要支援 Server Push 了

Twitter 上看到 nginx 的 HTTP/2 也要支援 server push 的消息了:

看起來是只要送出對應的 HTTP Header,後續 nginx 就會幫你處理...

這功能總算是要進 nginx 了... 像是透過 cookie 判斷使用者是第一次瀏覽,就透過 server push 預先把 css/js 丟出去,加速頁面呈現。

Googlebot 的 Math.random()

Hacker News Daily 上看到「Googlebot’s Javascript random() function is deterministic」這則有趣的發現。作者發現 Googlebot 的 Math.random() 並不隨機,甚至是固定的:

The first time Googlebot calls Math.random() the result will always be 0.14881141134537756, the second call will always be 0.19426893815398216. The script I linked to above simply uses this fact but obfuscates it a little and ‘seed’ it with something that doesn’t look too arbitrary.

需要無法預測的 random number (有安全性需求的) 應該用 RandomSource.getRandomValues() 這類函數,而不是用 Math.random(),所以這點倒是還好...

SSL Certificate 的認證方式限縮

在「Ballot 218 - Remove validation methods 1 and 5 - CAB Forum」看到「Ballot 218: Remove validation methods #1 and #5」這則議案以 78% 的同意票通過,限縮 SSL Certificate 的認證方式。眼睛瞄到中華電信投下反對票:

14 Yes votes: CFCA, Cisco, Comodo CA, D-TRUST, DigiCert, GDCA, GlobalSign, GoDaddy, Izenpe, Let’s Encrypt, Logius PKIoverheid, SSL.com, TrustCor, Trustwave

4 No votes: Buypass, Chunghwa Telecom, Entrust Datacard, SwissSign

4 Abstain: Actalis, Disig, HARICA, OATI

78% of voting CAs voted in favor

找了一下在 BR (Baseline Requirements) 的 3.2.2.4.1 與 3.2.2.4.5,其中前者是透過註冊商認證:

3.2.2.4.1 Validating the Applicant as a Domain Contact

Confirming the Applicant's control over the FQDN by validating the Applicant is the Domain Contact directly with the Domain Name Registrar.

後者是透過文件認證:

3.2.2.4.5 Domain Authorization Document

Confirming the Applicant's control over the FQDN by relying upon the attestation to the authority of the Applicant to request a Certificate contained in a Domain Authorization Document.

在想投下反對的原因,會不會是因為中華自己的 domain 應該都是透過後者方式發的?透過內部公文系統...

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