1:5.5p1-4ubuntu4 (scp <host>:ns_sys_config) problem

[Damjan Zajc]

My configuration is:
Ubuntu 10.10 (maverick) i386, 2.6.35-22-generic

When I want to download a configuration of device I get a this report (command is: scp -v 172.30.250.14:ns_sys_config test.cfg):

Executing: program /usr/bin/ssh host 172.30.250.14, user (unspecified), command scp -v -f -- ns_sys_config
OpenSSH_5.5p1 Debian-4ubuntu4, OpenSSL 0.9.8o 01 Jun 2010
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Applying options for *
debug1: Connecting to 172.30.250.14 [172.30.250.14] port 22.
debug1: Connection established.
debug1: identity file /home/zajcd/.ssh/id_rsa type 1
debug1: Checking blacklist file /usr/share/ssh/blacklist.RSA-2048
debug1: Checking blacklist file /etc/ssh/blacklist.RSA-2048
debug1: identity file /home/zajcd/.ssh/id_rsa-cert type -1
debug1: identity file /home/zajcd/.ssh/id_dsa type 2
debug1: Checking blacklist file /usr/share/ssh/blacklist.DSA-1024
debug1: Checking blacklist file /etc/ssh/blacklist.DSA-1024
debug1: identity file /home/zajcd/.ssh/id_dsa-cert type -1
debug1: Remote protocol version 2.0, remote software version NetScreen
debug1: no match: NetScreen
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.5p1 Debian-4ubuntu4
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client 3des-cbc hmac-sha1 none
debug1: kex: client->server 3des-cbc hmac-sha1 none
debug1: sending SSH2_MSG_KEXDH_INIT
debug1: expecting SSH2_MSG_KEXDH_REPLY
debug1: Host '172.30.250.14' is known and matches the DSA host key.
debug1: Found key in /home/zajcd/.ssh/known_hosts:24
debug1: ssh_dss_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey,password
debug1: Next authentication method: publickey
debug1: Offering public key: /home/zajcd/.ssh/id_dsa
debug1: Server accepts key: pkalg ssh-dss blen 435
debug1: Authentication succeeded (publickey).
debug1: channel 0: new [client-session]
debug1: Entering interactive session.
debug1: Sending environment.
debug1: Sending env LANG = en_US.utf8
debug1: Sending command: scp -v -f -- ns_sys_config
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug1: channel 0: free: client-session, nchannels 1
debug1: fd 0 clearing O_NONBLOCK
debug1: fd 1 clearing O_NONBLOCK
Transferred: sent 2384, received 1464 bytes, in 0.1 seconds
Bytes per second: sent 29048.0, received 17838.2
debug1: Exit status 1

The problem is: Download configuration shall not be made.
In older version hat command works fine.

In older Ubuntu version is different line:
Ubuntu 10.10: debug1: Sending command: scp -v -f -- ns_sys_config
Ubuntu 10.04: debug1: Sending command: scp -v -f ns_sys_config

[Chuck Short (zulcss)]

What OS is the computer you are trying to copy the file from?

chuck

[Damjan Zajc (dzajc21)]

Computer OS whitch do copy is Juniper routers.

Dx3

[Launchpad Janitor (janitor)]

[Expired for openssh (Ubuntu) because there has been no activity for 60 days.]

[Mike Mackintosh (mike-mackintosh)]

I am able to duplicate this issue, with Ubuntu 11.04 and 11.10, it is also affecting Debian Sarge and Squeeze.

debug1: Authentication succeeded (password).
debug1: channel 0: new [client-session]
debug1: Entering interactive session.
debug1: Sending environment.
debug1: Sending env LANG = en_US.UTF-8
debug1: Sending command: scp -v -f -- /ns_sys_config
debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
debug1: channel 0: free: client-session, nchannels 1
debug1: fd 0 clearing O_NONBLOCK
debug1: fd 1 clearing O_NONBLOCK

The issue is that the remote devices are not full SSH/SCP capable devices and register the -- after -f as a filename, which does not exist.

[Mike Mackintosh (mike-mackintosh)]

I downloaded the enw version of SSH:

http://filedump.se.rit.edu/pub/OpenBSD/OpenSSH/portable/openssh-5.9p1.tar.gz

I extracted and searched the source for `-f --`

The -f is a hidden flag to tell the host to expect a file, but I cannot find any documentation as to what the -- is for.

i did a search and replace on -f -- to -f in scp.c in the extracted directory.

I ran make and make install.

From the new SCP binary, the -f -- no longer was issued, only -f.

Issue was resolved for me. I can submit a patch in a moment.

[Mike Mackintosh (mike-mackintosh)]

Patch submitted to remove -- from scp -v -f -- <file name>

Some systems read the -- as being part of the file name.

[Mike Mackintosh (mike-mackintosh)]

To apply patch use the following

In the source code directory:

patch -p1 -i scp.patch

[Javier Domingo (txomon)]

which is the actual state of the bug? Is there any way to fix it definitely?

[Mike Mackintosh (mike-mackintosh)]

No. OpenSSH will not apply a fix to this since the above is working as desired. This issue is actually related to netssh code, which Juniper has fixed it in 6.2.0r11.

Changelog shows:

585314— SCP to the firewall failed from an UNIX machine and displayed the error "unknown file '--ns_sys_config."

[Mike Mackintosh (mike-mackintosh)]

This is an issue with a 3rd party system.

[Mike Mackintosh (mike-mackintosh)]

Bug with 3rd party system.