Tcl

Get the SSH Server's Authentication Methods

Demonstrates the Chilkat Ssh.GetAuthMethods method, which queries a connected but unauthenticated SSH server for the authentication methods it advertises. It takes no arguments and returns a lowercase, comma-separated list such as publickey,password,keyboard-interactive. Call it after Connect and before authenticating.

Background: Knowing what the server accepts lets a client choose the right authentication path — for example, falling back to keyboard-interactive when password auth is not offered. Note the documented connection side effect: querying methods advances the SSH authentication state, so call it at the correct point in the sequence.

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Tcl


load ./chilkat.dll

set success 0

#  Demonstrates the Ssh.GetAuthMethods method, which queries a connected but unauthenticated SSH
#  server for the authentication methods it advertises.  It takes no arguments and returns a
#  lowercase, comma-separated list such as "publickey,password,keyboard-interactive".

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
}

#  Query the advertised authentication methods.  Call after Connect, before authenticating.
set methods [CkSsh_getAuthMethods $ssh]
if {[CkSsh_get_LastMethodSuccess $ssh] == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

puts "Server auth methods: $methods"

CkSsh_Disconnect $ssh

delete_CkSsh $ssh