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Unicode C

SFTP Auth Failure Reason (AuthenticatePwPk)

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This example demonstrates how to determine the failure reason for the case where both a password and private key are required for authentication. If authentication fails, was it because of an invalid private key, or an invalid password?

Chilkat Unicode C Downloads

Unicode C
#include <C_CkSshKeyW.h>
#include <C_CkSFtpW.h>
#include <C_CkJsonObjectW.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkSshKeyW key;
    HCkSFtpW sftp;
    HCkJsonObjectW json;

    success = FALSE;

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

    // Load a private key to be used for SSH authentication.
    key = CkSshKeyW_Create();
    CkSshKeyW_putPassword(key,L"key_password");

    success = CkSshKeyW_FromOpenSshPrivateKey(key,CkSshKeyW_loadText(key,L"qa_data/my_private_key_file"));
    if (success == FALSE) {
        wprintf(L"%s\n",CkSshKeyW_lastErrorText(key));
        CkSshKeyW_Dispose(key);
        return;
    }

    sftp = CkSFtpW_Create();

    success = CkSFtpW_Connect(sftp,L"sftp.example.com",22);
    if (success == FALSE) {
        wprintf(L"%s\n",CkSFtpW_lastErrorText(sftp));
        CkSshKeyW_Dispose(key);
        CkSFtpW_Dispose(sftp);
        return;
    }

    // Authenticate using both a password and private key.
    success = CkSFtpW_AuthenticatePwPk(sftp,L"myLogin",L"myPassword",key);
    if (success == TRUE) {
        wprintf(L"Authentication is successful!\n");
        CkSshKeyW_Dispose(key);
        CkSFtpW_Dispose(sftp);
        return;
    }

    // If we get here, it means the authentication failed.
    // Examine the last JSON data..

    json = CkJsonObjectW_Create();
    CkSFtpW_GetLastJsonData(sftp,json);

    CkJsonObjectW_putEmitCompact(json,FALSE);

    // This is the JSON if the key is correct, but the password is incorrect:

    // {
    //   "public_key_type": "rsa",
    //   "partialAuthResult": "publickey success. continue to authenticate with password...",
    //   "authResult": "failed",
    //   "authFailReason": "Password is incorrect"
    // }

    // This is the JSON if the key is incorrect.  We won't know if the password is also incorrect until
    // the key is made correct so that authentication proceeds to check the password.

    // {
    //   "public_key_type": "rsa",
    //   "authResult": "failed",
    //   "authFailReason": "Key is incorrect"
    // }

    // To get the authResult anbd authFailReason:
    wprintf(L"authResult: %s\n",CkJsonObjectW_stringOf(json,L"authResult"));
    wprintf(L"authFailReason: %s\n",CkJsonObjectW_stringOf(json,L"authFailReason"));


    CkSshKeyW_Dispose(key);
    CkSFtpW_Dispose(sftp);
    CkJsonObjectW_Dispose(json);

    }