Tcl

SSH Authenticate with Password and Private Key

Demonstrates the Chilkat Ssh.AuthenticatePwPk method, which authenticates with a server that requires both a password and a private key. The first argument is the username, the second is the password, and the third is an SshKey private key.

Note: The private-key path is relative to the application's current working directory. Supply the path to your own key file.

Background: Most servers require either a password or a public key, not both — but some high-security configurations mandate multi-factor SSH, combining something you know (the password) with something you have (the key). This method satisfies that policy in one call. As always, the password should come from a secure source rather than a literal in code.

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Tcl


load ./chilkat.dll

set success 0

#  Demonstrates the Ssh.AuthenticatePwPk method, which authenticates with a server that requires
#  BOTH a password and a private key.  The 1st argument is the username, the 2nd is the
#  password, and the 3rd is an SshKey private key.

set ssh [new_CkSsh]

#  Connect to the SSH server.  Port 22 is the usual SSH port.
set sshPort 22
set success [CkSsh_Connect $ssh "ssh.example.com" $sshPort]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

#  Normally you would not hard-code the password in source.  You should instead obtain it
#  from an interactive prompt, environment variable, or a secrets vault.
set password "mySshPassword"

#  Load the SSH private key.  LoadText reads the file's text, which is then imported.
set privKey [new_CkSshKey]

set keyStr [CkSshKey_loadText $privKey "qa_data/id_rsa"]
if {[CkSshKey_get_LastMethodSuccess $privKey] == 0} then {
    puts [CkSshKey_lastErrorText $privKey]
    delete_CkSsh $ssh
    delete_CkSshKey $privKey
    exit
}

set success [CkSshKey_FromOpenSshPrivateKey $privKey $keyStr]
if {$success == 0} then {
    puts [CkSshKey_lastErrorText $privKey]
    delete_CkSsh $ssh
    delete_CkSshKey $privKey
    exit
}

set success [CkSsh_AuthenticatePwPk $ssh "mySshLogin" $password $privKey]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkSshKey $privKey
    exit
}

puts "Authenticated with password and private key."

CkSsh_Disconnect $ssh

delete_CkSsh $ssh
delete_CkSshKey $privKey