From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS4713 221.184.0.0/13 X-Spam-Status: No, score=-3.1 required=3.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, FORGED_GMAIL_RCVD,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED, SPF_PASS,WEIRD_PORT shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from neon.ruby-lang.org (neon.ruby-lang.org [221.186.184.75]) by dcvr.yhbt.net (Postfix) with ESMTP id ABC0920248 for ; Thu, 28 Feb 2019 11:51:26 +0000 (UTC) Received: from neon.ruby-lang.org (localhost [IPv6:::1]) by neon.ruby-lang.org (Postfix) with ESMTP id 02FA6121FEA; Thu, 28 Feb 2019 20:51:22 +0900 (JST) Received: from o1678916x28.outbound-mail.sendgrid.net (o1678916x28.outbound-mail.sendgrid.net [167.89.16.28]) by neon.ruby-lang.org (Postfix) with ESMTPS id 45218121F81 for ; Thu, 28 Feb 2019 20:51:21 +0900 (JST) Received: by filter0064p3iad2.sendgrid.net with SMTP id filter0064p3iad2-8544-5C77CB36-1B 2019-02-28 11:51:18.550650187 +0000 UTC m=+365715.767905750 Received: from herokuapp.com (ec2-35-153-142-167.compute-1.amazonaws.com [35.153.142.167]) by ismtpd0012p1iad1.sendgrid.net (SG) with ESMTP id HXZDDtT0SFKc-PzmYgQKbQ for ; Thu, 28 Feb 2019 11:51:18.275 +0000 (UTC) Date: Thu, 28 Feb 2019 11:51:19 +0000 (UTC) From: aditya.prakash132@gmail.com To: ruby-core@ruby-lang.org Message-ID: References: Mime-Version: 1.0 X-Redmine-MailingListIntegration-Message-Ids: 67091 X-Redmine-Project: ruby-trunk X-Redmine-Issue-Id: 15628 X-Redmine-Issue-Author: sonalkr132 X-Redmine-Sender: sonalkr132 X-Mailer: Redmine X-Redmine-Host: bugs.ruby-lang.org X-Redmine-Site: Ruby Issue Tracking System X-Auto-Response-Suppress: All Auto-Submitted: auto-generated X-SG-EID: ync6xU2WACa70kv/Ymy4QrNMhiuLXJG8OTL2vJD1yS48Udw8tpSbgdX9jjPVjOG9yieZVl50KF5JaL 0ze/STGwVEXgmidgL34BbFGovNXCLvwWIuvswh1K+42Ks3qrIKV0CyjYdRTqqtg84bLmdoujFknA5a 21kxgqnQ7a6Q76lylrAudr+4mpr3TAa5V8qPVSWN3zjP0pOxc4YxknSE1g== X-ML-Name: ruby-core X-Mail-Count: 91641 Subject: [ruby-core:91641] [Ruby trunk Feature#15628] init_inetsock_internal should fallback to IPv4 if IPv6 is unreachable X-BeenThere: ruby-core@ruby-lang.org X-Mailman-Version: 2.1.15 Precedence: list Reply-To: Ruby developers List-Id: Ruby developers List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ruby-core-bounces@ruby-lang.org Sender: "ruby-core" Issue #15628 has been reported by sonalkr132 (Aditya Prakash). ---------------------------------------- Feature #15628: init_inetsock_internal should fallback to IPv4 if IPv6 is unreachable https://bugs.ruby-lang.org/issues/15628 * Author: sonalkr132 (Aditya Prakash) * Status: Open * Priority: Normal * Assignee: * Target version: ---------------------------------------- Hi, This is not really bug but more of a missing feature. Let me layout steps to reproduce what I am trying to achieve: * Add local entries for `example.com` ``` $ echo "::1 example.com www.example.com 127.0.0.1 example.com www.example.com" | sudo tee --append /etc/hosts ``` * Add rule to `DROP` ipv6 packets: `sudo ip6tables -P INPUT DROP` * Start a server: `ruby -rwebrick -e 'WEBrick::HTTPServer.new(Port: 8000).start'` * Making request using Net:HTTP with timeout (`Net::OpenTimeout`) after after 60 seconds: `ruby -rnet/http -e "Net::HTTP.get(URI('http://example.com:8000'))"` As far as I understand, [init_inetsock_internal](https://github.com/ruby/ruby/blob/4444025d16ae1a586eee6a0ac9bdd09e33833f3c/ext/socket/ipsocket.c#L42) needs to fallback to ipv4 for Net::HTTP.get to work. IPv6 route being broke is expected and hence, [RFC8305](https://tools.ietf.org/html/rfc8305) recommends fallback to IPv4. Support for IPv6 fallback is spotty across languages and http clients, for example, [golang supports it](https://github.com/golang/go/blob/master/src/net/dial.go#L47) but python doesn't, making request with `curl` works but `wget` hangs. -- https://bugs.ruby-lang.org/