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C++

Generate RSA SSH Key

See more SSH Key Examples

Generates an RSA SSH key and saves to various public and private key file formats (OpenSSH and PuTTY).

Chilkat C++ Downloads

C++
#include <CkSshKey.h>

void ChilkatSample(void)
    {
    bool success = false;

    CkSshKey key;

    // numBits may range from 384 to 4096.  Typical values are
    // 1024 or 2048.  (must be a multiple of 64)
    // A good choice for the exponent is 65537.  Chilkat recommends
    // always using this value.
    int numBits = 2048;
    int exponent = 65537;
    success = key.GenerateRsaKey(numBits,exponent);
    if (success != true) {
        std::cout << "Bad params passed to RSA key generation method." << "\r\n";
        return;
    }

    // Note: Generating a public/private key pair is CPU intensive
    // and may take a short amount of time (more than few seconds,
    // but less than a minute).

    const char *exportedKey = 0;
    bool exportEncrypted;

    // Export the RSA private key to OpenSSH, PuTTY, and XML and save. 
    exportEncrypted = false;
    exportedKey = key.toOpenSshPrivateKey(exportEncrypted);
    // Chilkat provides a SaveText method for convenience...
    success = key.SaveText(exportedKey,"privkey_openssh_unencrypted.pem");

    // Export with encryption to OpenSSH private key format:
    key.put_Password("secret");
    exportEncrypted = true;
    exportedKey = key.toOpenSshPrivateKey(exportEncrypted);
    success = key.SaveText(exportedKey,"privkey_openssh_encrypted.pem");

    // Export the RSA private key to unencrypted PuTTY format:
    exportEncrypted = false;
    exportedKey = key.toPuttyPrivateKey(exportEncrypted);
    success = key.SaveText(exportedKey,"privkey_putty_unencrypted.ppk");

    // Export the RSA private key to encrypted PuTTY format:
    key.put_Password("secret");
    exportEncrypted = true;
    exportedKey = key.toPuttyPrivateKey(exportEncrypted);
    success = key.SaveText(exportedKey,"privkey_putty_encrypted.ppk");

    // Export private key to XML:
    exportedKey = key.toXml();
    success = key.SaveText(exportedKey,"privkey.xml");

    // ----------------------------------------------------
    // Now for the public key....
    // ----------------------------------------------------

    // The Secure Shell (SSH) Public Key File Format
    // is documented in RFC 4716.
    exportedKey = key.toRfc4716PublicKey();
    success = key.SaveText(exportedKey,"pubkey_rfc4716.pub");

    // OpenSSH has a separate public-key file format, which 
    // is also supported by Chilkat SshKey:
    exportedKey = key.toOpenSshPublicKey();
    success = key.SaveText(exportedKey,"pubkey_openSsh.pub");

    std::cout << "Finished." << "\r\n";
    }