Re: bin/56129 (ftp(1) should keep control session during large xfer)

[RVP <rvp%SDF.ORG@localhost>]

The following reply was made to PR bin/56129; it has been noted by GNATS.

From: RVP <rvp%SDF.ORG@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: lukem%netbsd.org@localhost, tsutsui%ceres.dti.ne.jp@localhost
Subject: Re: bin/56129 (ftp(1) should keep control session during large
 xfer)
Date: Sun, 20 Jun 2021 20:38:24 +0000 (UTC)

 On Sat, 19 Jun 2021, RVP wrote:
 
 > I'm inclined to blame the FTP NAT impl. on my ISP-provided DSL-router.
 >
 
 In my case it definitely is the broken FTP NAT in my DSL-router:
 
 In the previous FTP download tests, since:
 
 base.tar.xz -> DL time = 42313304 bytes received in 23:44 -> ctl. conn OK
 comp.tar.xz -> DL time = 60781064 bytes received in 34:06 -> ctl. conn closed
 
 I set TCP keepalive to 20 mins:
 
 $ sudo sysctl -w net.inet.tcp.keepidle=$(( (20*60) * $(sysctl -n net.inet.tcp.slowhz) ))
 
 And, using NetBSD-ftp 20210603, all the files came through without a
 hitch:
 
 -----
 $ ftp -T get,30000 -d ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-9.2/amd64/binary/sets/*.xz
 Get transfer rate throttle: on; maximum: 30000; increment 1024.
 isipv6addr: got 0 for ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-9.2/amd64/binary/sets/*.xz
 fetch_ftp: `ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-9.2/amd64/binary/sets/*.xz'
 parse_url: URL `ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-9.2/amd64/binary/sets/*.xz'
 parse_url: user `<null>' pass `<null>' host ftp.netbsd.org port ftp(21) path `pub/NetBSD/NetBSD-9.2/amd64/binary/sets/*.xz'
 fetch_ftp: user `<null>' pass `<null>' host ftp.netbsd.org port ftp path `pub/NetBSD/NetBSD-9.2/amd64/binary/sets' dir `pub/NetBSD/NetBSD-9.2/amd64/binary/sets' file `*.xz'
 Trying [2001:470:a085:999::21]:21 ...
 setupsockbufsize: rcvbuf_size determined as 32768
 setupsockbufsize: sndbuf_size determined as 32768
 ftp: Can't connect to `2001:470:a085:999::21:21': No route to host
 Trying 199.233.217.201:21 ...
 Connected to ftp.netbsd.org.
 220 ftp.NetBSD.org FTP server (NetBSD-ftpd 20180428) ready.
 ftp_login: user `<null>' pass `<null>' host `ftp.netbsd.org'
 ---> USER anonymous
 331 Guest login ok, type your name as password.
 ---> PASS XXXX
 230-
 
 ...
 
 19703048 bytes received in 11:08 (28.79 KiB/s)
 ---> MDTM xserver.tar.xz
 213 20210512195146
 remotemodtime: parsed time `20210512195146' as 1620849106, Wed, 12 May 2021 19:51:46 +0000
 ---> QUIT
 221-
      Data traffic for this session was 696130340 bytes in 21 files.
      Total traffic for this session was 696140384 bytes in 22 transfers.
 221 Thank you for using the FTP service on ftp.NetBSD.org.
 $ 
 -----
 
 Reinforcing my notion that my DSL router has a flawed FTP NAT impl.,
 I see that NetBSD sending a RST packet after the ctl. conn. is closed:
 
 -----
 08:49:51.192501 IP 192.168.68.121.65314 > 199.233.217.201.21: Flags [F.], seq 321, ack 4693, win 4197, options [nop,nop,TS val 23453 ecr 21360], length 0
 08:50:55.192257 IP 192.168.68.121.65314 > 199.233.217.201.21: Flags [F.], seq 321, ack 4693, win 4197, options [nop,nop,TS val 23581 ecr 21360], length 0
 08:51:59.192000 IP 192.168.68.121.65314 > 199.233.217.201.21: Flags [F.], seq 321, ack 4693, win 4197, options [nop,nop,TS val 23709 ecr 21360], length 0
 08:53:03.191753 IP 192.168.68.121.65314 > 199.233.217.201.21: Flags [F.], seq 321, ack 4693, win 4197, options [nop,nop,TS val 23837 ecr 21360], length 0
 08:54:07.191498 IP 192.168.68.121.65314 > 199.233.217.201.21: Flags [R.], seq 322, ack 4693, win 4197, length 0
 -----
 
 causes my wired connection to the wireless extender to drop its
 carrier (this happens pretty consistently, though god knows why):
 
 -----
 Jun 20 08:55:58 x202e dhcpcd[444]: alc0: carrier lost - roaming
 Jun 20 08:56:17 x202e dhcpcd[444]: alc0: carrier acquired
 Jun 20 08:56:17 x202e dhcpcd[444]: alc0: IAID 5d:32:67:54
 Jun 20 08:56:18 x202e dhcpcd[444]: alc0: soliciting an IPv6 router
 Jun 20 08:56:19 x202e dhcpcd[444]: alc0: Router Advertisement from fe80::da47:32ff:fea8:b288
 Jun 20 08:56:19 x202e dhcpcd[444]: alc0: no global addresses for default route
 Jun 20 08:56:19 x202e dhcpcd[444]: alc0: soliciting a DHCPv6 lease
 Jun 20 08:57:18 x202e dhcpcd[444]: alc0: carrier lost - roaming
 Jun 20 08:57:35 x202e dhcpcd[444]: alc0: carrier acquired
 Jun 20 08:57:35 x202e dhcpcd[444]: alc0: IAID 5d:32:67:54
 Jun 20 08:57:36 x202e dhcpcd[444]: alc0: soliciting an IPv6 router
 Jun 20 08:57:36 x202e dhcpcd[444]: alc0: Router Advertisement from fe80::da47:32ff:fea8:b288
 Jun 20 08:57:36 x202e dhcpcd[444]: alc0: no global addresses for default route
 Jun 20 08:57:36 x202e dhcpcd[444]: alc0: soliciting a DHCPv6 lease
 -----
 
 -RVP