xref: /third_party/openssl/demos/cms/cms_denc.c (revision e1051a39)
1/*
2 * Copyright 2008-2016 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License").  You may not use
5 * this file except in compliance with the License.  You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10/*
11 * S/MIME detached data encrypt example: rarely done but should the need
12 * arise this is an example....
13 */
14#include <openssl/pem.h>
15#include <openssl/cms.h>
16#include <openssl/err.h>
17
18int main(int argc, char **argv)
19{
20    BIO *in = NULL, *out = NULL, *tbio = NULL, *dout = NULL;
21    X509 *rcert = NULL;
22    STACK_OF(X509) *recips = NULL;
23    CMS_ContentInfo *cms = NULL;
24    int ret = 1;
25
26    int flags = CMS_STREAM | CMS_DETACHED;
27
28    OpenSSL_add_all_algorithms();
29    ERR_load_crypto_strings();
30
31    /* Read in recipient certificate */
32    tbio = BIO_new_file("signer.pem", "r");
33
34    if (!tbio)
35        goto err;
36
37    rcert = PEM_read_bio_X509(tbio, NULL, 0, NULL);
38
39    if (!rcert)
40        goto err;
41
42    /* Create recipient STACK and add recipient cert to it */
43    recips = sk_X509_new_null();
44
45    if (!recips || !sk_X509_push(recips, rcert))
46        goto err;
47
48    /*
49     * sk_X509_pop_free will free up recipient STACK and its contents so set
50     * rcert to NULL so it isn't freed up twice.
51     */
52    rcert = NULL;
53
54    /* Open content being encrypted */
55
56    in = BIO_new_file("encr.txt", "r");
57
58    dout = BIO_new_file("smencr.out", "wb");
59
60    if (!in)
61        goto err;
62
63    /* encrypt content */
64    cms = CMS_encrypt(recips, in, EVP_des_ede3_cbc(), flags);
65
66    if (!cms)
67        goto err;
68
69    out = BIO_new_file("smencr.pem", "w");
70    if (!out)
71        goto err;
72
73    if (!CMS_final(cms, in, dout, flags))
74        goto err;
75
76    /* Write out CMS structure without content */
77    if (!PEM_write_bio_CMS(out, cms))
78        goto err;
79
80    ret = 0;
81
82 err:
83
84    if (ret) {
85        fprintf(stderr, "Error Encrypting Data\n");
86        ERR_print_errors_fp(stderr);
87    }
88
89    CMS_ContentInfo_free(cms);
90    X509_free(rcert);
91    sk_X509_pop_free(recips, X509_free);
92    BIO_free(in);
93    BIO_free(out);
94    BIO_free(dout);
95    BIO_free(tbio);
96    return ret;
97}
98