Get the SSH Server's Authentication Methods

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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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#include <C_CkSsh.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkSsh ssh;
    int sshPort;
    const char *methods;

    success = FALSE;

    //  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".

    ssh = CkSsh_Create();

    //  Connect to the SSH server.  Port 22 is the usual SSH port.
    sshPort = 22;
    success = CkSsh_Connect(ssh,"ssh.example.com",sshPort);
    if (success == FALSE) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        CkSsh_Dispose(ssh);
        return;
    }

    //  Query the advertised authentication methods.  Call after Connect, before authenticating.
    methods = CkSsh_getAuthMethods(ssh);
    if (CkSsh_getLastMethodSuccess(ssh) == FALSE) {
        printf("%s\n",CkSsh_lastErrorText(ssh));
        CkSsh_Dispose(ssh);
        return;
    }

    printf("Server auth methods: %s\n",methods);

    CkSsh_Disconnect(ssh);


    CkSsh_Dispose(ssh);

    }