Sample code for 30+ languages & platforms
C++

Convert PuTTY Private Key (ppk) to OpenSSH (pem)

See more SSH Key Examples

Convert a PuTTY format private key file (.ppk) to OpenSSH (.pem).

Chilkat C++ Downloads

C++
#include <CkSshKey.h>

void ChilkatSample(void)
    {
    bool success = false;

    CkSshKey key;

    // Load an unencrypted or encrypted PuTTY private key.

    // If  your PuTTY private key is encrypted, set the Password
    // property before calling FromPuttyPrivateKey.
    // If your PuTTY private key is not encrypted, it makes no diffference
    // if Password is set or not set.
    key.put_Password("secret");

    // First load the .ppk file into a string:
    const char *keyStr = 0;
    keyStr = key.loadText("putty_private_key.ppk");

    // Import into the SSH key object:
    success = key.FromPuttyPrivateKey(keyStr);
    if (success != true) {
        std::cout << key.lastErrorText() << "\r\n";
        return;
    }

    // Convert to an encrypted or unencrypted OpenSSH key.

    // First demonstrate converting to an unencrypted OpenSSH key
    const char *unencryptedKeyStr = 0;
    bool bEncrypt = false;
    unencryptedKeyStr = key.toOpenSshPrivateKey(bEncrypt);
    success = key.SaveText(unencryptedKeyStr,"unencrypted_openssh.pem");
    if (success != true) {
        std::cout << key.lastErrorText() << "\r\n";
        return;
    }

    // Save to an encrypted OpenSSH PEM file:
    const char *encryptedKeyStr = 0;
    bEncrypt = true;
    key.put_Password("myPassword");
    encryptedKeyStr = key.toOpenSshPrivateKey(bEncrypt);
    success = key.SaveText(encryptedKeyStr,"encrypted_openssh.pem");
    if (success != true) {
        std::cout << key.lastErrorText() << "\r\n";
        return;
    }

    std::cout << "Done!" << "\r\n";
    }