(C) RSA Decrypt using PEM

This example demonstrates decryping RSA encrypted data that is base64 encoded. It uses a private key loaded from a PEM file.

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

void ChilkatSample(void)
    {
    HCkRsa rsa;
    HCkPrivateKey key;
    BOOL success;
    const char *encryptedStr;
    BOOL usePrivateKey;
    const char *decryptedStr;

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

    rsa = CkRsa_Create();

    key = CkPrivateKey_Create();

    // Load an RSA private key from an unencrypted PEM file:
    // (To load from an encrypted PEM file, call LoadEncryptedPemFile instead.)

    success = CkPrivateKey_LoadPemFile(key,"qa_data/rsa/decryptTest/priv.pem");
    if (success != TRUE) {
        printf("%s\n",CkPrivateKey_lastErrorText(key));
        CkRsa_Dispose(rsa);
        CkPrivateKey_Dispose(key);
        return;
    }

    // Make the key available to the RSA object
    success = CkRsa_ImportPrivateKeyObj(rsa,key);
    if (success != TRUE) {
        printf("%s\n",CkRsa_lastErrorText(rsa));
        CkRsa_Dispose(rsa);
        CkPrivateKey_Dispose(key);
        return;
    }

    encryptedStr = "pP9XFJEsGgxPNHEgNiLB5H5ksCOXDk/G49BPTog1jKLAhYofV4UTH5k2TOYiqRnDnKs8+8uPoN/IxdiGXvuYG8HRzN0HtkhoZO/AxeyaB9S7eddCUlT0Pl2PEB2yQ9HG5rM7jqYOD6MAM4cuX7hqT8fa8tbzJzmBwdfFDBz94bwQjULHiO+gklIBC4vhkXT4yjuvEjxTAKU6tJeZYkBooJNdS/vE5RZRpuF6bGZU41Qc17qFR+iReBq+9f8IMmw8WR8fMbOCaygOfFS1nw7JVsIMGsAIXS8rUaJ/2DfGPfQx5HCiVtTOreGYRUI3esAQjnvUCnavZyQgs53nl7e2aA==";

    CkRsa_putEncodingMode(rsa,"base64");

    usePrivateKey = TRUE;
    decryptedStr = CkRsa_decryptStringENC(rsa,encryptedStr,usePrivateKey);

    printf("Decrypted:\n");
    printf("%s\n",decryptedStr);


    CkRsa_Dispose(rsa);
    CkPrivateKey_Dispose(key);

    }