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Unicode C

SFTP Public-Key Authentication (id_ed25519)

See more SFTP Examples

Demonstrates how to authenticate with an SSH/SFTP server using publickey authentication with an Ed25519 private key (id_ed25519).

Chilkat Unicode C Downloads

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

void ChilkatSample(void)
    {
    BOOL success;
    HCkSshKeyW key;
    const wchar_t *privKeyText;
    HCkSFtpW sftp;
    const wchar_t *hostname;
    int port;

    success = FALSE;

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

    key = CkSshKeyW_Create();

    // The id_ed25519 file should contain something like this:
    // (You can open it in a text editor..)

    // -----BEGIN OPENSSH PRIVATE KEY-----
    // b3BlbnNzaC1rZXktdjEAAAAACmFlczI1Ni1jdHIAAAAGYmNyeXB0AAAAGAAAABDIeK9+Xw
    // 6Do9gnhtrJu5iJAAAAZAAAAAEAAAAzAAAAC3NzaC1lZDI1NTE5AAAAIMh/Ge7fjQCssmVd
    // BqjYZbRAI0pY8IrnB6J1yLetq34OAAAAoMVP7cvy4hTiAINA3I4v55OonkpKza8mzfUW18
    // RDQeYL3ovCVaAYOGcCpf/SW3QiY6tnXq+5WDEfJ7Z/kQ0nl2+1wSLOytxpyO+IY0rRtLrX
    // 6e/agR4nbZpt/MFG6xqcNASbtDgg+9IWGvDrtXOLFofx07/zml+UjFL0tXRpCjOxeqKyXH
    // t8SRgdT97d9/bYPwapaXY+b2DVVy5/LVx4Sq8=
    // -----END OPENSSH PRIVATE KEY-----

    privKeyText = CkSshKeyW_loadText(key,L"c:/temp/id_ed25519");
    if (CkSshKeyW_getLastMethodSuccess(key) != TRUE) {
        wprintf(L"%s\n",CkSshKeyW_lastErrorText(key));
        CkSshKeyW_Dispose(key);
        return;
    }

    // If your private key was saved encrypted, then you'll need the password.
    // In this example, the password "blahblah" is valid for the above key -- which is a real Ed25519 key generated/saved from puttygen.
    CkSshKeyW_putPassword(key,L"blahblah");

    success = CkSshKeyW_FromOpenSshPrivateKey(key,privKeyText);
    if (success != TRUE) {
        wprintf(L"%s\n",CkSshKeyW_lastErrorText(key));
        CkSshKeyW_Dispose(key);
        return;
    }

    sftp = CkSFtpW_Create();

    // Set some timeouts, in milliseconds:
    CkSFtpW_putConnectTimeoutMs(sftp,5000);
    CkSFtpW_putIdleTimeoutMs(sftp,15000);

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

    // Authenticate with the SSH server.  Chilkat SFTP supports
    // both password-based authenication as well as public-key
    // authentication.  
    success = CkSFtpW_AuthenticatePk(sftp,L"myLogin",key);
    if (success != TRUE) {
        wprintf(L"%s\n",CkSFtpW_lastErrorText(sftp));
        CkSshKeyW_Dispose(key);
        CkSFtpW_Dispose(sftp);
        return;
    }

    wprintf(L"%s\n",CkSFtpW_lastErrorText(sftp));
    wprintf(L"Public-Key Authentication Successful!\n");

    // Now go do whatever you're app needs to do...


    CkSshKeyW_Dispose(key);
    CkSFtpW_Dispose(sftp);

    }