PureBasic

SSH Tunnel Authenticate with Password and Private Key

Demonstrates the Chilkat SshTunnel.AuthenticatePwPk method, which authenticates with a server that requires both a password and a private key. The arguments are the username, the password, and an SshKey private key.

Note: The private-key path is relative to the application's current working directory. Absolute paths may also be used. 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 deployments mandate two-factor SSH. This method satisfies that policy in one call, combining something you know (the password) with something you have (the key). The password should come from a secure source rather than a literal.

Chilkat PureBasic Downloads

Download Chilkat for PureBasic

PureBasic

IncludeFile "CkSshTunnel.pb"
IncludeFile "CkSshKey.pb"

Procedure ChilkatExample()

    success.i = 0

    ;  Demonstrates the SshTunnel.AuthenticatePwPk method, which authenticates with an SSH 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.

    tunnel.i = CkSshTunnel::ckCreate()
    If tunnel.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ;  The tunnel forwards accepted local connections to this destination through the SSH server.
    CkSshTunnel::setCkDestHostname(tunnel, "db.internal.example.com")
    CkSshTunnel::setCkDestPort(tunnel, 5432)

    ;  Connect to the SSH server.  This performs the TCP/proxy connection and SSH handshake, but
    ;  does not authenticate yet.
    sshPort.i = 22
    success = CkSshTunnel::ckConnect(tunnel,"ssh.example.com",sshPort)
    If success = 0
        Debug CkSshTunnel::ckLastErrorText(tunnel)
        CkSshTunnel::ckDispose(tunnel)
        ProcedureReturn
    EndIf

    ;  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.
    password.s = "mySshPassword"

    ;  Load the SSH private key.  LoadText reads the file's text, which is then imported.
    privKey.i = CkSshKey::ckCreate()
    If privKey.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    keyText.s = CkSshKey::ckLoadText(privKey,"qa_data/id_rsa")
    If CkSshKey::ckLastMethodSuccess(privKey) = 0
        Debug CkSshKey::ckLastErrorText(privKey)
        CkSshTunnel::ckDispose(tunnel)
        CkSshKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    success = CkSshKey::ckFromOpenSshPrivateKey(privKey,keyText)
    If success = 0
        Debug CkSshKey::ckLastErrorText(privKey)
        CkSshTunnel::ckDispose(tunnel)
        CkSshKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    success = CkSshTunnel::ckAuthenticatePwPk(tunnel,"mySshLogin",password,privKey)
    If success = 0
        Debug CkSshTunnel::ckLastErrorText(tunnel)
        CkSshTunnel::ckDispose(tunnel)
        CkSshKey::ckDispose(privKey)
        ProcedureReturn
    EndIf

    Debug "Authenticated with a password and a private key."

    ;  After authenticating, call BeginAccepting to start listening for local connections to forward.

    waitForThreadExit.i = 1
    success = CkSshTunnel::ckCloseTunnel(tunnel,waitForThreadExit)
    If success = 0
        Debug CkSshTunnel::ckLastErrorText(tunnel)
        CkSshTunnel::ckDispose(tunnel)
        CkSshKey::ckDispose(privKey)
        ProcedureReturn
    EndIf



    CkSshTunnel::ckDispose(tunnel)
    CkSshKey::ckDispose(privKey)


    ProcedureReturn
EndProcedure