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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 C Downloads

C
#include <C_CkSshKey.h>
#include <C_CkSFtp.h>
#include <C_CkJsonObject.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkSshKey key;
    HCkSFtp sftp;
    HCkJsonObject 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 = CkSshKey_Create();
    CkSshKey_putPassword(key,"key_password");

    success = CkSshKey_FromOpenSshPrivateKey(key,CkSshKey_loadText(key,"qa_data/my_private_key_file"));
    if (success == FALSE) {
        printf("%s\n",CkSshKey_lastErrorText(key));
        CkSshKey_Dispose(key);
        return;
    }

    sftp = CkSFtp_Create();

    success = CkSFtp_Connect(sftp,"sftp.example.com",22);
    if (success == FALSE) {
        printf("%s\n",CkSFtp_lastErrorText(sftp));
        CkSshKey_Dispose(key);
        CkSFtp_Dispose(sftp);
        return;
    }

    // Authenticate using both a password and private key.
    success = CkSFtp_AuthenticatePwPk(sftp,"myLogin","myPassword",key);
    if (success == TRUE) {
        printf("Authentication is successful!\n");
        CkSshKey_Dispose(key);
        CkSFtp_Dispose(sftp);
        return;
    }

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

    json = CkJsonObject_Create();
    CkSFtp_GetLastJsonData(sftp,json);

    CkJsonObject_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:
    printf("authResult: %s\n",CkJsonObject_stringOf(json,"authResult"));
    printf("authFailReason: %s\n",CkJsonObject_stringOf(json,"authFailReason"));


    CkSshKey_Dispose(key);
    CkSFtp_Dispose(sftp);
    CkJsonObject_Dispose(json);

    }