Linux – How to copy a file without using scp inside an ssh session

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I have logged on to a system with ssh and there is no scp present on both the systems. How to copy a file without using the scp program.

Best Answer

To send a file:

cat file | ssh ajw@dogmatix "cat > remote"

Or:

ssh ajw@dogmatix "cat > remote" < file

To receive a file:

ssh ajw@dogmatix "cat remote" > copy

Related Solutions

SSH Configuration – Can SSH Be Used Without SCP?

Apparently, it is possible (according to post #3 at that link). The trick is in the authorized_keys file format. There are several options that allow the server to restrict SSH features based on what key was used to authenticate. The "command=" option allows the server administrator to attach a restriction on the public key -- something like

"any incoming connections that authenticate with this key will execute this command, regardless of what command might have been requested by the user".

It might prevent the execution of standard SCP and SFTP, but if it provides an interactive shell there's probably a way around it:

$ ssh user@host 'cat /some/where/whatiwant.txt' > igotit.txt

How using ssh/scp between non-public machines

You want to set up port forwarding. When you SSH from machine A to machine B add a tunnel, i.e. add -L 1234:A:22 when tunnelling to B. Then SSH to machine C and scp the files to B on port 1234 (i.e. add -P 1234 to scp). This will actually route to port 22 on machine A which is the ssh port and hence it'll transfer directly.

I don't have three machines with which to try this right now but I think this should work.

Best Answer

Related Solutions

SSH Configuration – Can SSH Be Used Without SCP?

How using ssh/scp between non-public machines

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