SFTP Authenticate with Password and Private Key

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Demonstrates the Chilkat SFtp.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. 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, 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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#include <C_CkSFtp.h>
#include <C_CkSshKey.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkSFtp sftp;
    int port;
    const char *password;
    HCkSshKey privKey;
    const char *keyText;

    success = FALSE;

    //  Demonstrates the SFtp.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.

    sftp = CkSFtp_Create();

    //  Step 1: Connect the SSH transport.  Port 22 is the usual port.
    port = 22;
    success = CkSFtp_Connect(sftp,"sftp.example.com",port);
    if (success == FALSE) {
        printf("%s\n",CkSFtp_lastErrorText(sftp));
        CkSFtp_Dispose(sftp);
        return;
    }

    //  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 = "mySshPassword";

    //  Load the SSH private key.  LoadText reads the file's text, which is then imported.
    privKey = CkSshKey_Create();
    keyText = CkSshKey_loadText(privKey,"qa_data/id_rsa");
    if (CkSshKey_getLastMethodSuccess(privKey) == FALSE) {
        printf("%s\n",CkSshKey_lastErrorText(privKey));
        CkSFtp_Dispose(sftp);
        CkSshKey_Dispose(privKey);
        return;
    }

    success = CkSshKey_FromOpenSshPrivateKey(privKey,keyText);
    if (success == FALSE) {
        printf("%s\n",CkSshKey_lastErrorText(privKey));
        CkSFtp_Dispose(sftp);
        CkSshKey_Dispose(privKey);
        return;
    }

    success = CkSFtp_AuthenticatePwPk(sftp,"mySshLogin",password,privKey);
    if (success == FALSE) {
        printf("%s\n",CkSFtp_lastErrorText(sftp));
        CkSFtp_Dispose(sftp);
        CkSshKey_Dispose(privKey);
        return;
    }

    //  Step 3: Open the SFTP subsystem.  This must be done after authentication and before any
    //  file or directory operations.
    success = CkSFtp_InitializeSftp(sftp);
    if (success == FALSE) {
        printf("%s\n",CkSFtp_lastErrorText(sftp));
        CkSFtp_Dispose(sftp);
        CkSshKey_Dispose(privKey);
        return;
    }

    printf("Authenticated with a password and a private key.\n");

    CkSFtp_Disconnect(sftp);


    CkSFtp_Dispose(sftp);
    CkSshKey_Dispose(privKey);

    }