1*4724848cSchristos /*
2*4724848cSchristos * Copyright 2008-2016 The OpenSSL Project Authors. All Rights Reserved.
3*4724848cSchristos *
4*4724848cSchristos * Licensed under the OpenSSL license (the "License"). You may not use
5*4724848cSchristos * this file except in compliance with the License. You can obtain a copy
6*4724848cSchristos * in the file LICENSE in the source distribution or at
7*4724848cSchristos * https://www.openssl.org/source/license.html
8*4724848cSchristos */
9*4724848cSchristos
10c9496f6bSchristos /* Simple S/MIME signing example */
11c9496f6bSchristos #include <openssl/pem.h>
12c9496f6bSchristos #include <openssl/cms.h>
13c9496f6bSchristos #include <openssl/err.h>
14c9496f6bSchristos
main(int argc,char ** argv)15c9496f6bSchristos int main(int argc, char **argv)
16c9496f6bSchristos {
17c9496f6bSchristos BIO *in = NULL, *out = NULL, *tbio = NULL;
18c9496f6bSchristos X509 *scert = NULL;
19c9496f6bSchristos EVP_PKEY *skey = NULL;
20c9496f6bSchristos CMS_ContentInfo *cms = NULL;
21c9496f6bSchristos int ret = 1;
22c9496f6bSchristos
23c9496f6bSchristos /*
24c9496f6bSchristos * For simple S/MIME signing use CMS_DETACHED. On OpenSSL 1.0.0 only: for
25c9496f6bSchristos * streaming detached set CMS_DETACHED|CMS_STREAM for streaming
26c9496f6bSchristos * non-detached set CMS_STREAM
27c9496f6bSchristos */
28c9496f6bSchristos int flags = CMS_DETACHED | CMS_STREAM;
29c9496f6bSchristos
30c9496f6bSchristos OpenSSL_add_all_algorithms();
31c9496f6bSchristos ERR_load_crypto_strings();
32c9496f6bSchristos
33c9496f6bSchristos /* Read in signer certificate and private key */
34c9496f6bSchristos tbio = BIO_new_file("signer.pem", "r");
35c9496f6bSchristos
36c9496f6bSchristos if (!tbio)
37c9496f6bSchristos goto err;
38c9496f6bSchristos
39c9496f6bSchristos scert = PEM_read_bio_X509(tbio, NULL, 0, NULL);
40c9496f6bSchristos
41c9496f6bSchristos BIO_reset(tbio);
42c9496f6bSchristos
43c9496f6bSchristos skey = PEM_read_bio_PrivateKey(tbio, NULL, 0, NULL);
44c9496f6bSchristos
45c9496f6bSchristos if (!scert || !skey)
46c9496f6bSchristos goto err;
47c9496f6bSchristos
48c9496f6bSchristos /* Open content being signed */
49c9496f6bSchristos
50c9496f6bSchristos in = BIO_new_file("sign.txt", "r");
51c9496f6bSchristos
52c9496f6bSchristos if (!in)
53c9496f6bSchristos goto err;
54c9496f6bSchristos
55c9496f6bSchristos /* Sign content */
56c9496f6bSchristos cms = CMS_sign(scert, skey, NULL, in, flags);
57c9496f6bSchristos
58c9496f6bSchristos if (!cms)
59c9496f6bSchristos goto err;
60c9496f6bSchristos
61c9496f6bSchristos out = BIO_new_file("smout.txt", "w");
62c9496f6bSchristos if (!out)
63c9496f6bSchristos goto err;
64c9496f6bSchristos
65c9496f6bSchristos if (!(flags & CMS_STREAM))
66c9496f6bSchristos BIO_reset(in);
67c9496f6bSchristos
68c9496f6bSchristos /* Write out S/MIME message */
69c9496f6bSchristos if (!SMIME_write_CMS(out, cms, in, flags))
70c9496f6bSchristos goto err;
71c9496f6bSchristos
72c9496f6bSchristos ret = 0;
73c9496f6bSchristos
74c9496f6bSchristos err:
75c9496f6bSchristos
76c9496f6bSchristos if (ret) {
77c9496f6bSchristos fprintf(stderr, "Error Signing Data\n");
78c9496f6bSchristos ERR_print_errors_fp(stderr);
79c9496f6bSchristos }
80c9496f6bSchristos
81c9496f6bSchristos CMS_ContentInfo_free(cms);
82c9496f6bSchristos X509_free(scert);
83c9496f6bSchristos EVP_PKEY_free(skey);
84c9496f6bSchristos BIO_free(in);
85c9496f6bSchristos BIO_free(out);
86c9496f6bSchristos BIO_free(tbio);
87c9496f6bSchristos return ret;
88c9496f6bSchristos }
89