


#include <openssl/pem.h>
#include <openssl/cms.h>
#include <openssl/err.h>

int main(int argc, char **argv)
{
    BIO *in = NULL, *out = NULL, *tbio = NULL, *dcont = NULL;
    X509 *rcert = NULL;
    EVP_PKEY *rkey = NULL;
    CMS_ContentInfo *cms = NULL;
    int ret = EXIT_FAILURE;

    OpenSSL_add_all_algorithms();
    ERR_load_crypto_strings();

    
    tbio = BIO_new_file("signer.pem", "r");

    if (!tbio)
        goto err;

    rcert = PEM_read_bio_X509(tbio, NULL, 0, NULL);

    if (BIO_reset(tbio) < 0)
        goto err;

    rkey = PEM_read_bio_PrivateKey(tbio, NULL, 0, NULL);

    if (!rcert || !rkey)
        goto err;

    

    in = BIO_new_file("smencr.pem", "r");

    if (!in)
        goto err;

    
    cms = PEM_read_bio_CMS(in, NULL, 0, NULL);

    if (!cms)
        goto err;

    
    dcont = BIO_new_file("smencr.out", "rb");

    if (!in)
        goto err;

    out = BIO_new_file("encrout.txt", "w");
    if (!out)
        goto err;

    
    if (!CMS_decrypt(cms, rkey, rcert, dcont, out, 0))
        goto err;

    ret = EXIT_SUCCESS;

 err:

    if (ret != EXIT_SUCCESS) {
        fprintf(stderr, "Error Decrypting Data\n");
        ERR_print_errors_fp(stderr);
    }

    CMS_ContentInfo_free(cms);
    X509_free(rcert);
    EVP_PKEY_free(rkey);
    BIO_free(in);
    BIO_free(out);
    BIO_free(tbio);
    BIO_free(dcont);
    return ret;
}
