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Unicode C++

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

See more RSA Examples

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

Chilkat Unicode C++ Downloads

Unicode C++
#include <CkPrivateKeyW.h>
#include <CkRsaW.h>

void ChilkatSample(void)
    {
    bool success = false;

    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkPrivateKeyW pkey;

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

    CkRsaW rsa;

    // Import the private key into the RSA component:
    success = rsa.UsePrivateKey(pkey);
    if (success == false) {
        wprintf(L"%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(L"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 wchar_t *strData = L"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 wchar_t *base64Sig = rsa.signStringENC(strData,L"md5");

    wprintf(L"%s\n",base64Sig);

    wprintf(L"Success!\n");
    }