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/* Simple S/MIME signing example */
#include <openssl/pem.h>
#include <openssl/pkcs7.h>
#include <openssl/err.h>
int main(int argc, char **argv)
{
BIO *in = NULL, *out = NULL, *tbio = NULL;
X509 *rcert = NULL;
EVP_PKEY *rkey = NULL;
PKCS7 *p7 = NULL;
int ret = 1;
OpenSSL_add_all_algorithms();
ERR_load_crypto_strings();
/* Read in recipient certificate and private key */
tbio = BIO_new_file("signer.pem", "r");
if (!tbio)
goto err;
rcert = PEM_read_bio_X509(tbio, NULL, 0, NULL);
BIO_reset(tbio);
rkey = PEM_read_bio_PrivateKey(tbio, NULL, 0, NULL);
if (!rcert || !rkey)
goto err;
/* Open content being signed */
in = BIO_new_file("smencr.txt", "r");
if (!in)
goto err;
/* Sign content */
p7 = SMIME_read_PKCS7(in, NULL);
if (!p7)
goto err;
out = BIO_new_file("encrout.txt", "w");
if (!out)
goto err;
/* Decrypt S/MIME message */
if (!PKCS7_decrypt(p7, rkey, rcert, out, 0))
goto err;
ret = 0;
err:
if (ret)
{
fprintf(stderr, "Error Signing Data\n");
ERR_print_errors_fp(stderr);
}
if (p7)
PKCS7_free(p7);
if (rcert)
X509_free(rcert);
if (rkey)
EVP_PKEY_free(rkey);
if (in)
BIO_free(in);
if (out)
BIO_free(out);
if (tbio)
BIO_free(tbio);
return ret;
}
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