an example of scp in golang

go_scp.go

// https://blogs.oracle.com/janp/entry/how_the_scp_protocol_works
package main

import (
	"fmt"

	"golang.org/x/crypto/ssh"
)

const privateKey = `content of id_rsa`

func main() {
	signer, _ := ssh.ParsePrivateKey([]byte(privateKey))
	clientConfig := &ssh.ClientConfig{
		User: "jedy",
		Auth: []ssh.AuthMethod{
			ssh.PublicKeys(signer),
		},
	}
	client, err := ssh.Dial("tcp", "127.0.0.1:22", clientConfig)
	if err != nil {
		panic("Failed to dial: " + err.Error())
	}
	session, err := client.NewSession()
	if err != nil {
		panic("Failed to create session: " + err.Error())
	}
	defer session.Close()
	go func() {
		w, _ := session.StdinPipe()
		defer w.Close()
		content := "123456789\n"
		fmt.Fprintln(w, "D0755", 0, "testdir") // mkdir
		fmt.Fprintln(w, "C0644", len(content), "testfile1")
		fmt.Fprint(w, content)
		fmt.Fprint(w, "\x00") // transfer end with \x00
		fmt.Fprintln(w, "C0644", len(content), "testfile2")
		fmt.Fprint(w, content)
		fmt.Fprint(w, "\x00")
	}()
	if err := session.Run("/usr/bin/scp -tr ./"); err != nil {
		panic("Failed to run: " + err.Error())
	}
}

Thank you for great job !

How can I determine "command" to send in Stdin ?

• D0775 : D for directory (?) and next chars for permissions
• C0644 : C for… create (?) and next chars for permissions

Do you have any links about theses instructions ? I searched in scp manual with no success.

[UPDATE]

I can found this post (thanks Web Archive) which gives commands availables. More, after few research it seems that SCP commands are not defined in any RFC.

@baptistedonaux God bless you! Helped me a lot!

Awesome! ty

This is working for me, and the file is copied over correctly, but the call to Run always returns an error: Process exited with status 1

session.Run("/usr/bin/scp -tr /tmp/")

anyone have any clues as to why this would be?

Got it!
I was writing a binary file, so I need this in-place of fmt.Fprint(w, content):

io.Copy(w, bytes.NewReader(galaArchive))