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/* Simple S/MIME encrypt 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;
STACK_OF(X509) *recips = NULL;
PKCS7 *p7 = NULL;
int ret = 1;
/*
* On OpenSSL 0.9.9 only:
* for streaming set PKCS7_STREAM
*/
int flags = PKCS7_STREAM;
OpenSSL_add_all_algorithms();
ERR_load_crypto_strings();
/* Read in recipient certificate */
tbio = BIO_new_file("signer.pem", "r");
if (!tbio)
goto err;
rcert = PEM_read_bio_X509(tbio, NULL, 0, NULL);
if (!rcert)
goto err;
/* Create recipient STACK and add recipient cert to it */
recips = sk_X509_new_null();
if (!recips || !sk_X509_push(recips, rcert))
goto err;
/*
* sk_X509_pop_free will free up recipient STACK and its contents so set
* rcert to NULL so it isn't freed up twice.
*/
rcert = NULL;
/* Open content being encrypted */
in = BIO_new_file("encr.txt", "r");
if (!in)
goto err;
/* encrypt content */
p7 = PKCS7_encrypt(recips, in, EVP_des_ede3_cbc(), flags);
if (!p7)
goto err;
out = BIO_new_file("smencr.txt", "w");
if (!out)
goto err;
/* Write out S/MIME message */
if (!SMIME_write_PKCS7(out, p7, in, flags))
goto err;
ret = 0;
err:
if (ret) {
fprintf(stderr, "Error Encrypting Data\n");
ERR_print_errors_fp(stderr);
}
if (p7)
PKCS7_free(p7);
if (rcert)
X509_free(rcert);
if (recips)
sk_X509_pop_free(recips, X509_free);
BIO_free(in);
BIO_free(out);
BIO_free(tbio);
return ret;
}
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