1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
|
/* 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 *scert = NULL;
EVP_PKEY *skey = NULL;
PKCS7 *p7 = NULL;
int ret = 1;
/*
* For simple S/MIME signing use PKCS7_DETACHED. On OpenSSL 0.9.9 only:
* for streaming detached set PKCS7_DETACHED|PKCS7_STREAM for streaming
* non-detached set PKCS7_STREAM
*/
int flags = PKCS7_DETACHED | PKCS7_STREAM;
OpenSSL_add_all_algorithms();
ERR_load_crypto_strings();
/* Read in signer certificate and private key */
tbio = BIO_new_file("signer.pem", "r");
if (!tbio)
goto err;
scert = PEM_read_bio_X509(tbio, NULL, 0, NULL);
BIO_reset(tbio);
skey = PEM_read_bio_PrivateKey(tbio, NULL, 0, NULL);
if (!scert || !skey)
goto err;
/* Open content being signed */
in = BIO_new_file("sign.txt", "r");
if (!in)
goto err;
/* Sign content */
p7 = PKCS7_sign(scert, skey, NULL, in, flags);
if (!p7)
goto err;
out = BIO_new_file("smout.txt", "w");
if (!out)
goto err;
if (!(flags & PKCS7_STREAM))
BIO_reset(in);
/* Write out S/MIME message */
if (!SMIME_write_PKCS7(out, p7, in, flags))
goto err;
ret = 0;
err:
if (ret) {
fprintf(stderr, "Error Signing Data\n");
ERR_print_errors_fp(stderr);
}
if (p7)
PKCS7_free(p7);
if (scert)
X509_free(scert);
if (skey)
EVP_PKEY_free(skey);
BIO_free(in);
BIO_free(out);
BIO_free(tbio);
return ret;
}
|