simple_ssh_copy

Transfer files to and from small or old POSIX-like devices over SSH.

This package intentionally avoids SFTP/SCP subsystems. It only needs a working SSH login and a few basic POSIX shell commands, so it is useful for minimal Linux systems, embedded devices, rescue environments, and older SSH servers.

Features

• Upload a local file to a remote host.
• Download a remote file to the local machine.
• Download a remote directory recursively.
• Aborts with a yellow warning when the remote system is detected as Windows.
• Prints the remote architecture detected with uname -m before transfers.
• Password, empty-password, SSH agent, ~/.ssh key, and explicit private-key authentication.
• Broad SSH algorithm compatibility enabled by default. During Paramiko transport setup, the client allows every currently supported key exchange, cipher, MAC/digest, server host key, and public-key signature algorithm that can be used by the active Paramiko transport.

For implementation notes, transfer flow, block sizes, and compatibility details, see Technical Details.

Install

pip install simple_ssh_copy

For local development:

pip install -e .

Command Line

Upload a file:

python -m simple_ssh_copy ./test-file.txt root@192.168.1.10:/home/root/test-file.txt

Download a file:

python -m simple_ssh_copy root@192.168.1.10:/home/root/test-file.txt ./test-file.txt

Use a non-default port:

python -m simple_ssh_copy ./test-file.txt root@192.168.1.10:2222:/home/root/test-file.txt

Use an explicit private key:

python -m simple_ssh_copy -i ~/.ssh/id_rsa ./test-file.txt root@192.168.1.10:/home/root/test-file.txt

On Windows:

python -m simple_ssh_copy -i C:\Users\neko\.ssh\id_rsa .\test-file.txt root@169.254.115.127:/home/root/test-file.txt

Increase the SSH timeout:

python -m simple_ssh_copy --timeout 60 ./test-file.txt root@192.168.1.10:/home/root/test-file.txt

When prompted for a password, press Enter for empty-password or key-only login. In that case the client also tries SSH agent and keys discoverable in ~/.ssh.

Python API

import simple_ssh_copy

hostname = "192.168.1.10"
username = "root"
password = ""

simple_ssh_copy.upload(
    hostname=hostname,
    username=username,
    password=password,
    files=[("./test-file.txt", "/home/root/test-file.txt")],
    key_filename="~/.ssh/id_rsa",
)

simple_ssh_copy.download(
    hostname=hostname,
    username=username,
    password=password,
    files=[("/home/root/test-file.txt", "./test-file.txt")],
    key_filename="~/.ssh/id_rsa",
)

simple_ssh_copy.download_dir(
    hostname=hostname,
    username=username,
    password=password,
    remote_dir="/home/root/logs",
    local_dir="./logs",
    key_filename="~/.ssh/id_rsa",
)

Run a remote command with the low-level client:

from simple_ssh_copy import SimpleSSHClient

with SimpleSSHClient(
    hostname="192.168.1.10",
    username="root",
    password="",
    key_filename="~/.ssh/id_rsa",
) as ssh:
    code, stdout, stderr = ssh.exec_cmd("uname -a")

SSH Algorithm Compatibility

Some old devices require options like:

ssh -o HostKeyAlgorithms=+ssh-rsa \
    -o MACs=+hmac-sha1-96,hmac-sha1,hmac-md5 \
    -i ~/.ssh/id_rsa root@192.168.1.10

simple_ssh_copy enables a broader Paramiko-side compatibility mode by default. It advertises all key exchange, cipher, MAC/digest, server host key, and public-key signature algorithms registered by the active Paramiko transport, while preserving Paramiko's default preference order first. It also restores ssh-rsa host keys and RSA public-key signatures when Paramiko can use them.

The matching file-transfer command is usually:

python -m simple_ssh_copy -i ~/.ssh/id_rsa ./file root@192.168.1.10:/tmp/file

If you need stricter modern SSH behavior, pass allow_ssh_rsa_host_key=False from the Python API. The parameter name is kept for API compatibility, but disabling it skips the broader compatibility transport setup.

Path Format

Remote paths use one of these formats:

user@host:/remote/path
user@host:port:/remote/path

Only local-to-remote and remote-to-local transfers are supported. Remote-to- remote transfers are not supported.

Limitations

• The remote host must provide a POSIX-like shell.
• Non-POSIX SSH servers, such as Windows command-shell SSH sessions, are not supported. Windows remotes are detected after SSH connection setup and abort with a yellow warning before file operations begin.
• Transfer startup reports the remote architecture with uname -m.
• Upload uses mkdir and base64 on the remote host.
• Upload sends base64 fragments through bounded remote commands, then decodes the assembled temporary file on the remote host.
• Download uses stat, dd, and find for directory downloads.
• Directory upload is not implemented.
• Very large uploads may be slower than real SCP/SFTP because data is written through remote shell commands.