Lua

SSH Public Key Authentication

Demonstrates authenticating with an SSH server using public-key authentication. A private key is loaded into an SshKey object and passed to AuthenticatePk. The matching public key must already be installed on the server for the account.

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

Background: Public-key authentication is the standard for unattended and automated SSH: the private key never leaves the client, the server merely trusts the corresponding public key, and no reusable password crosses the wire. SshKey imports several formats — OpenSSH PEM keys via FromOpenSshPrivateKey and PuTTY .ppk files via FromPuttyPrivateKey — encrypted or not. For an encrypted key, set the Password property before importing. Note that LoadText is only a convenience for reading a text file into a string; it does not itself load the key.

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Lua

local chilkat = require("chilkat")

-- This example requires the Chilkat API to have been previously unlocked.
-- See Global Unlock Sample for sample code.

-- Demonstrates authenticating with an SSH server using public-key authentication.  The matching
-- public key must already be installed on the SSH server for the account.

local ssh = chilkat.Ssh.new()

-- Timeouts, in milliseconds.
ssh.connect_timeout_ms = 5000
ssh.read_timeout_ms = 15000

local hostname = "ssh.example.com"
local port = 22
local success = ssh:connect(hostname, port)
if not success then
    print(ssh.last_error_text)
    return
end

-- LoadText is a convenience method that reads any text file into a string.  It does not itself
-- load the key.
local key = chilkat.SshKey.new()
local privKeyText = key:load_text("qa_data/my_private_key.pem")
if not key.last_method_success then
    print(key.last_error_text)
    return
end

-- Import the private key.  Both OpenSSH and PuTTY formats are supported, encrypted or not.
-- This example loads an unencrypted OpenSSH-format key; for a PuTTY .ppk file, call
-- FromPuttyPrivateKey instead.  For an encrypted key, set key.Password before importing.
success = key:from_open_ssh_private_key(privKeyText)
if not success then
    print(key.last_error_text)
    return
end

success = ssh:authenticate_pk("mySshLogin", key)
if not success then
    print(ssh.last_error_text)
    return
end

print("Public-key authentication successful.")

ssh:disconnect()