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

void ChilkatSample(void)
    {
    HCkPrivateKey pkey;
    BOOL success;
    const char * pkeyXml;
    HCkRsa rsa;
    const char * strData;
    const char * base64Sig;

    pkey = CkPrivateKey_Create();

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

    //  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("%s\n",CkRsa_lastErrorText(rsa));
        return;
    }

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

    //  OpenSSL uses BigEndian byte ordering:
    CkRsa_putLittleEndian(rsa,FALSE);

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

    //  For simplicity, we're not loading
    //  the data to be signed from a file.  We are instead simply
    //  using a literal string value.

    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".

    base64Sig = CkRsa_signStringENC(rsa,strData,"md5");

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

    printf("Success!\n");


    CkPrivateKey_Dispose(pkey);
    CkRsa_Dispose(rsa);

    }