Fresh install january 2020 - adding SSH/ SFTP source - sad face

Help and Support Vero 4K / Vero 4K +
80

Are there any news on this issue yet? I tried the pending update last night and the sftp error seems to still be in the current build.

81

I still donā€™t have a solution for this at this time.

Sam

82

Thank you for the reply. I am patient.

83

Hello all,

I have had this issue recently. As soon as I specified my SFTP host and credentials, I ended up with a sad face. I started over from a fresh install just to make sure I had not done something wrong. But the issue still persists.

Iā€™ve decided to do an analysis myself and hereā€™s what I came up with:

kodi.bin crashes with the following stack:

#0 0x00000000 in ?? ()
#1 0x70478dd2 in EVP_PKEY_get_raw_public_key ()
from /usr/lib/kodi/addons/vfs.sftp/vfs.sftp.so.1.0.5
#2 0x70432f50 in ssh_client_curve25519_init ()
from /usr/lib/kodi/addons/vfs.sftp/vfs.sftp.so.1.0.5
#3 0x7043204c in ssh_client_connection_callback ()
from /usr/lib/kodi/addons/vfs.sftp/vfs.sftp.so.1.0.5
#4 0x70434880 in ssh_packet_kexinit () from /usr/lib/kodi/addons/vfs.sftp/vfs.sftp.so.1.0.5
#5 0x7043ad16 in ssh_packet_process () from /usr/lib/kodi/addons/vfs.sftp/vfs.sftp.so.1.0.5
#6 0x7043b252 in ssh_packet_socket_callback ()
from /usr/lib/kodi/addons/vfs.sftp/vfs.sftp.so.1.0.5
#7 0x7043ffac in ssh_socket_pollcallback ()
from /usr/lib/kodi/addons/vfs.sftp/vfs.sftp.so.1.0.5
#8 0x70459512 in ssh_poll_ctx_dopoll () from /usr/lib/kodi/addons/vfs.sftp/vfs.sftp.so.1.0.5
#9 0x7043f260 in ssh_handle_packets () from /usr/lib/kodi/addons/vfs.sftp/vfs.sftp.so.1.0.5

It appears that the issue has something to do with Curve25519. I did not dig enough to find out exactly what is going on.

That being said, I was able to make SFTP work by forcing the SSH client to use a different key exchange algorithm.

Here is the list of steps I ran:

  1. SSH as the osmc user to the OSMC platform
  2. Make sure the ~/.ssh directory exists:
    mkdir ~/.ssh
  3. Edit the file ~/.ssh/config (if it does not exist, create it) to add the following directive:
    KexAlgorithms ecdh-sha2-nistp256

You can adapt the KexAlgorithms to match what your SSH server supports. You can specify multiple ones as long as you donā€™t include any 25519 ones.

Iā€™ll be happy to share this analysis to get this problem solved in OSMC.

Hope this will help :slight_smile:

Kind regards,
Olivier

84

I did try to build an unstripped verrsion of kodi.bin to look at this problem further but Samā€™s build environment is a bit (letā€™s say) convoluted and, in spite of my best efforts to hack it, always produced a stripped binary. Each build took 5-6 hours and by the third failed attempt I decided that it was not to be.

So your workaround is very welcome. Thank you.

1 Like
85

You can just remove the ā€˜stripā€™ line at the end of build.sh
A non stripped version is always placed in the debug-osmc.deb package anyway.

86

Hello camel_case,

THANK YOU so much for this fix. I tested it on a vero, vero 4k and raspberry 3. All are working fine with the current osmc release after I put the ssh config in. Now I can finaly update my raspberrys to a current version of osmc.

You helped me a lot.

1 Like
87

After noticing my Vero 4K had an update last week I checked again and the error persists; as soon as a sftp source is specified sad face and reboot.

88

We havenā€™t claimed to have fixed the issue yet.

89

This should now be solved with our support of Debian Buster.

90

Do I need to update to a newer version - or was it included in the june update?

91

It will be solved with the public release of Debian Buster.

1 Like
92

As of Nov 30 itā€™s (SFTP - as served by a Synology box) working for me, having updated my Vero earlier in the week.

1 Like
93

We released Debian Buster a while ago. This should have solved the issue.
Thanks for confirming.