From nobody Sat Dec 04 21:54:44 2021 X-Original-To: freebsd-net@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id A805D18978F9 for ; Sat, 4 Dec 2021 21:54:58 +0000 (UTC) (envelope-from dmarquess@gmail.com) Received: from mail-ed1-x52e.google.com (mail-ed1-x52e.google.com [IPv6:2a00:1450:4864:20::52e]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1D4" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4J63Q96xt7z3qQd for ; Sat, 4 Dec 2021 21:54:57 +0000 (UTC) (envelope-from dmarquess@gmail.com) Received: by mail-ed1-x52e.google.com with SMTP id l25so26409745eda.11 for ; Sat, 04 Dec 2021 13:54:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:from:date:message-id:subject:to; bh=Q/9xBmk+iUFm017DIJ+lnSxH8THnGHdFcAU+CdLpmJk=; b=InB9GhuXfE3FVe0y70e+Vf/q9LQoEHplWXlOwjduysJkfhEpRT639wjkIw4fLvKKSF SFIGL/4wyGq+9khq/dADXhvAHNTFVEYGcJBDbiPtJ+bcgRxNR+f3qo4hyrDQ2sIuNYkd tkEhWWyIXhYDiSDBkiK/0Z4VNaUE4rOwMMB4Z1g2WiN9JQM6VcTNhK7m2fNOnQA7o45v yun6pBdNdyO/QpBFqoq4GWzOYj+VaYi8FtcpnALTrO+/8NfZCzvsje9xdvW9Vcx7xUGP VKZjfH7iToispsYoPyZzvzZkUsdy9OnnFKzOh/lW7mxIBkKZV6Tq1UGaK9b7btM1+xLh A0DA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=Q/9xBmk+iUFm017DIJ+lnSxH8THnGHdFcAU+CdLpmJk=; b=v7yHHVTFNlcaO1zudUYJLRJuASKS5TePh9hFqCPefElzqxtrd1b97gmXyaDxVahTXJ uljAcLiFfxD3saG6N9muATF0kY2HLwuIMNv40X6jMeJtEG93HjRLbHYXCxtAYX5T27xN HWOZw/PzWsNHGuErp+WpbXoRECDH7TlD5SwUOLI3Ea2LlJPfiLeCnlXW6DOyVNPC7N81 A1PYhENJpr9eHwtwGgxH5z5/k3wR6tKmaQzQIH98HKqcaVXCnPXyUTp/ZptPNBA1P8/M gKjl/7n37zELNjdw7G74u3Mk05r/NUFEk9lL7yCZQFq1CseKCgTescHiQjWCC703+p8b IAhA== X-Gm-Message-State: AOAM531yfiA+/KvcS58OXzkecAEFmCAkjD9kS30At5fd9mg6/nh5Jxi2 yEa6RoTL1ssPINIGQbgL1EFcCo+YGSalqGfGA/ypWSwBjdKi1Q== X-Google-Smtp-Source: ABdhPJz3WnV4UUeh7r4Pi3MGJ4WHBf4h0lPumWOICDIAAg6J6oVzg5bQvw8rrsy+PmTxTwxOfjrbPOjVuB+011lhDoA= X-Received: by 2002:a17:906:398:: with SMTP id b24mr34134382eja.49.1638654896540; Sat, 04 Dec 2021 13:54:56 -0800 (PST) List-Id: Networking and TCP/IP with FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-net List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-net@freebsd.org MIME-Version: 1.0 From: Dustin Marquess Date: Sat, 4 Dec 2021 15:54:44 -0600 Message-ID: Subject: Weirdness with same-host IPv6 packets To: freebsd-net@freebsd.org Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: 4J63Q96xt7z3qQd X-Spamd-Bar: - Authentication-Results: mx1.freebsd.org; dkim=pass header.d=gmail.com header.s=20210112 header.b=InB9GhuX; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (mx1.freebsd.org: domain of dmarquess@gmail.com designates 2a00:1450:4864:20::52e as permitted sender) smtp.mailfrom=dmarquess@gmail.com X-Spamd-Result: default: False [-1.99 / 15.00]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-0.99)[-0.993]; R_DKIM_ALLOW(-0.20)[gmail.com:s=20210112]; FROM_HAS_DN(0.00)[]; FREEMAIL_FROM(0.00)[gmail.com]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; PREVIOUSLY_DELIVERED(0.00)[freebsd-net@freebsd.org]; TO_DN_NONE(0.00)[]; RCPT_COUNT_ONE(0.00)[1]; MID_RHS_MATCH_FROMTLD(0.00)[]; R_SPF_ALLOW(-0.20)[+ip6:2a00:1450:4000::/36]; DKIM_TRACE(0.00)[gmail.com:+]; DMARC_POLICY_ALLOW(-0.50)[gmail.com,none]; RCVD_IN_DNSWL_NONE(0.00)[2a00:1450:4864:20::52e:from]; NEURAL_HAM_SHORT(-1.00)[-0.999]; NEURAL_SPAM_LONG(1.00)[0.999]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; FREEMAIL_ENVFROM(0.00)[gmail.com]; ASN(0.00)[asn:15169, ipnet:2a00:1450::/32, country:US]; RCVD_COUNT_TWO(0.00)[2]; RCVD_TLS_ALL(0.00)[]; DWL_DNSWL_NONE(0.00)[gmail.com:dkim] X-ThisMailContainsUnwantedMimeParts: N I'm seeing a weird issue with -CURRENT that I don't recall seeing before. It started at least a couple of weeks back and a new build from yesterday still shows it. UDP packets inside a host using the host's non-loopback address seems to get dropped. TCP does work, however there's a delay, almost like the first packet or two also got dropped. I don't have any firewalling active, and stopping the VNET jails didn't have any effect. I've been using the machine's local IPv6 IP in /etc/resolv.conf for a while. I noticed that logins were taking longer than usual and tracked it down to unbound not responding. If I change /etc/resolv.conf to use ::1 or the host's IPv4 IP, then it works fine. The host's IPv6 IP does work from outside the host, however. I thought it was maybe a weird unbound bug, so I did some testing with netcat. Current ifconfg (other interfaces removed for brevity): lo0: flags=8049 metric 0 mtu 16384 options=680003 inet6 ::1 prefixlen 128 inet6 fe80::1%lo0 prefixlen 64 scopeid 0xb inet 127.0.0.1 netmask 0xff000000 nd6 options=21 groups: lo bridge2: flags=8843 metric 0 mtu 9000 ether 58:9c:fc:10:f4:55 inet 192.168.4.101 netmask 0xffffff00 broadcast 192.168.4.255 inet 192.168.4.12 netmask 0xffffffff broadcast 192.168.4.12 inet6 2001:470:bc52:4::101 prefixlen 64 id 00:00:00:00:00:00 priority 32768 hellotime 2 fwddelay 15 maxage 20 holdcnt 6 proto rstp maxaddr 2000 timeout 1200 root id 00:00:00:00:00:00 priority 32768 ifcost 0 port 0 member: tap2 flags=143 ifmaxaddr 0 port 16 priority 128 path cost 2000000 member: lagg0 flags=143 ifmaxaddr 0 port 12 priority 128 path cost 2000000 nd6 options=1 groups: bridge Routing table: Internet: Destination Gateway Flags Netif Expire default 192.168.4.1 UGS bridge2 127.0.0.1 link#11 UH lo0 192.168.4.0/24 link#19 U bridge2 192.168.4.12 link#19 UH lo0 192.168.4.101 link#19 UHS lo0 Internet6: Destination Gateway Flags Netif Expire ::/96 ::1 UGRS lo0 default 2001:470:bc52:4::1 UGS bridge2 ::1 link#11 UHS lo0 ::ffff:0.0.0.0/96 ::1 UGRS lo0 2001:470:bc52:4::/64 link#19 U bridge2 2001:470:bc52:4::101 link#19 UHS lo0 fe80::/10 ::1 UGRS lo0 fe80::%lo0/64 link#11 U lo0 fe80::1%lo0 link#11 UHS lo0 ff02::/16 ::1 UGRS lo0 Testing: I started a listener: $ nc -6 -u -l 5555 And in another window, did: $ echo testing | nc -6 -u ::1 5555 <-- Works $ echo testing | nc -6 -u 2001:470:bc52:4::101 5555 <-- Never receives the packet [ Previous command from a different host DOES work, however] Switching to TCP: $ echo testing | nc -6 ::1 5555 <--- Works $ echo testing | nc -6 2001:470:bc52:4::101 5555 <-- Works, after a delay however Trying IPv4: $ echo testing | nc -u 127.0.0.1 5555 <--- Works $ echo testing | nc -u 192.168.4.101 5555 <--- Works, no delay So IPv4 is working fine, which is strange. Has anybody else seen this and have any insight? -Dustin