From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ramon Fried <rfried.dev@gmail.com>
Date: Tue, 2 Feb 2021 21:46:47 +0200
Subject: [PATCH v5] net: tftp: Add client support for RFC 7440
In-Reply-To: <CAHPF-4++Ryep4A8aqoCv1j9y5cf-Lwjw8uJqPpAvmtQnPWXy3A@mail.gmail.com>
References: <20200718203146.317254-1-rfried.dev@gmail.com>
 <20200805202724.GY6965@bill-the-cat>
 <CAHPF-4LU7dSCoSRoy7hJZ-pLJRC_qAbuQdV33jLvPKVt8zEpBQ@mail.gmail.com>
 <CAGi-RUKJ=JNiN+DOBvYqzjzJjUeCMACi65zvKaiQM5Ef1MMhCg@mail.gmail.com>
 <CAGi-RUL=GyuMqcEnOH3AEkc4DuXcu5XWwF0o8-z9uGM=xDjivA@mail.gmail.com>
 <CAHPF-4++Ryep4A8aqoCv1j9y5cf-Lwjw8uJqPpAvmtQnPWXy3A@mail.gmail.com>
Message-ID: <CAGi-RUJhPmt8aHjaL+csLa3Ug=vs+zONtOAmr2Hn-24omYQd4Q@mail.gmail.com>
List-Id: <u-boot.lists.denx.de>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
To: u-boot@lists.denx.de

On Tue, Feb 2, 2021 at 6:02 PM Suneel Garapati <suneelglinux@gmail.com> wrote:
>
> On Mon, Feb 1, 2021 at 2:27 PM Ramon Fried <rfried.dev@gmail.com> wrote:
> >
> > On Sat, Jan 30, 2021 at 11:26 PM Ramon Fried <rfried.dev@gmail.com> wrote:
> > >
> > > On Sat, Jan 30, 2021 at 10:39 PM Suneel Garapati <suneelglinux@gmail.com> wrote:
> > > >
> > > > Hello Ramon,
> > > >
> > > > With TFTP window size as default 1 and enabling TFTPPUT config option
> > > > results in tftpboot command failure.
> > > >
> > > > Attached the pcap files for with and without TFTPPUT enabled.
> > > > Both captures are the same except that the TFTPPUT option enables ICMP handler
> > > > and for the response from the server triggers a restart of netloop
> > > > operation and eventually fails as below.
> > > >
> > > > > tftpboot 0x30000000 192.168.1.1:Image
> > > > Waiting for RPM0 LMAC0 link status... 10G_R [10G]
> > > > Using rvu_pf#0 device
> > > > TFTP from server 192.168.1.1; our IP address is 192.168.1.16
> > > > Filename 'Image'. Load address: 0x30000000
> > > > Loading: ################################################## 15.8 MiB
> > > > 787.1 KiB/s
> > > > done
> > > > TFTP server died; starting again
> > > > >
> > > >
> > > > I see the code issue as below on net/tftp.c [v2020.10] ?
> > > >                 /*
> > > >                  *      Acknowledge the block just received, which will prompt
> > > >                  *      the remote for the next one.
> > > >                  */
> > > >                 if (tftp_cur_block == tftp_next_ack) {
> > > >                         tftp_send();
> > > >                         tftp_next_ack += tftp_windowsize;
> > > >                 }
> > > >
> > > >                 if (len < tftp_block_size) {
> > > >                         //if (tftp_windowsize > 1) [Hack in use for
> > > > now to work around this issue]
> > > >                         tftp_send();                      [ This
> > > > causes extra ACK packet send with same block number and causes server
> > > > to respond with ICMP error]
> > > >                         tftp_complete();
> > > >                 }
> > > >
> > > > I couldn?t try with tftp_windowsize > 1 as the test servers don?t support.
> > > > I tried with all latest commits on net/tftp.c on top of v2020.10 and
> > > > still see the issue.
> > > >
> > > > This change is introduced in
> > > > commit cc6b87ecaa96325577a8fafabc0d5972b816bc6c
> > > > Author: Ramon Fried <rfried.dev@gmail.com>
> > > > Date:   Sat Jul 18 23:31:46 2020 +0300
> > > >
> > > >     net: tftp: Add client support for RFC 7440
> > > >
> > > >     Add support for RFC 7440: "TFTP Windowsize Option".
> > > >
> > > > Reverting this commit on v2020.10 also fixes the issue.
> > > >
> > > > I would like to know if this extra tftp_send is needed at all or only
> > > > for window size > 1
> > RFC7440 is not supported by most TFTP Servers, when adding support for
> > this feature I didn't even consider TFTPPUT.
> > I think that the best thing to do is to only support RFC7440 on TFTPGET.
> > In this case we should remove the tftp_send() when sending a file.
> > I will create a fix, would you mind testing to see if it works for you ?
> > Thanks,
> > Ramon.
> Yes, I can test the fix.
>
> Thanks,
> Suneel
> > > >
> > > > Regards,
> > > > Suneel
> > > Thanks for spotting this, I'll check it out.
Hey Suneel
Now when I dived deeper, I just figured out that __tftpboot__ doesn't
work for you with window size = 1.
This is very strange, my current setup is working also with this configuration.
Can you please check which TFTP server you're using on the other end ?

Thanks,
Ramon.