Duplicate openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

Demonstrates how to duplicate the creation of an RSA signature produced by this OpenSSL command:

openssl dgst -md5 -sign myKey.pem something.txt | openssl enc -base64 -A

Downloads:

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 <CkPrivateKey.h>
#include <CkRsa.h>

void ChilkatSample(void)
    {
    CkPrivateKey pkey;

    //  Load the private key from an RSA PEM file:
    pkey.LoadPemFile("myKey.pem");

    bool success;

    const char * pkeyXml;

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

    CkRsa rsa;

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

    success = rsa.UnlockComponent("30-day trial");
    if (success != true) {
        printf("%s\n",rsa.lastErrorText());
        return;
    }

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

    //  OpenSSL uses BigEndian byte ordering:
    rsa.put_LittleEndian(false);

    //  The resulting signature will be a Base64 string:
    rsa.put_EncodingMode("base64");

    //  For simplicity, we're not loading
    //  the data to be signed from a file.  We are instead simply
    //  using a literal string value.
    const char * strData;
    strData = "This is the text to be signed.";

    //  Hash the input using MD5, and then sign the hash:
    //  Other valid hash algorithm choices are "md2" and "sha-1".
    const char * base64Sig;
    base64Sig = rsa.signStringENC(strData,"md5");

    printf("%s\n",base64Sig);

    printf("Success!\n");

    }