RSA Sign with PKCS8 Encrypted Key

Demonstrates how to load a private key from an encrypted PKCS8 file and create an RSA digital signature.

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MS Windows Visual C/C++ Libraries

Linux/CentOS C/C++ Libraries

MAC OS X C/C++ Libraries

Solaris C/C++ Libraries

C++ Builder Libraries

#include <C_CkPrivateKey.h>
#include <C_CkRsa.h>

void ChilkatSample(void)
    {
    HCkPrivateKey pkey;
    BOOL success;
    const char * pkeyXml;
    HCkRsa rsa;
    const char * strData;
    const char * hexSig;

    pkey = CkPrivateKey_Create();

    //  Load the private key from an RSA PEM file:
    CkPrivateKey_LoadPkcs8EncryptedFile(pkey,"privateKey.key","myPassword");

    //  Get the private key in XML format:
    pkeyXml = CkPrivateKey_getXml(pkey);

    rsa = CkRsa_Create();

    //  Any string argument automatically begins the 30-day trial.

    success = CkRsa_UnlockComponent(rsa,"30-day trial");
    if (success != TRUE) {
        printf("RSA component unlock failed\n");
        return;
    }

    //  Import the private key into the RSA component:
    success = CkRsa_ImportPrivateKey(rsa,pkeyXml);
    if (success != TRUE) {
        printf("%s\n",CkRsa_lastErrorText(rsa));
        return;
    }

    //  This example will sign a string, and receive the signature
    //  in a hex-encoded string.  Therefore, set the encoding mode
    //  to "hex":
    CkRsa_putEncodingMode(rsa,"hex");

    //  If some other non-Chilkat application or web service is going to be verifying
    //  the signature, it is important to match the byte-ordering.
    //  The LittleEndian property may be set to TRUE
    //  for little-endian byte ordering,
    //  or FALSE  for big-endian byte ordering.
    //  Microsoft apps typically use little-endian, while
    //  OpenSSL and other services (such as Amazon CloudFront)
    //  use big-endian.
    CkRsa_putLittleEndian(rsa,FALSE);

    strData = "This is the string to be signed.";

    //  Sign the string using the sha-1 hash algorithm.
    //  Other valid choices are "md2", "sha256", "sha384", "sha512",  and "md5".

    hexSig = CkRsa_signStringENC(rsa,strData,"sha-1");

    printf("%s\n",hexSig);

    CkPrivateKey_Dispose(pkey);
    CkRsa_Dispose(rsa);

    }