1/* Simple S/MIME encrypt example */
2#include <openssl/pem.h>
3#include <openssl/pkcs7.h>
4#include <openssl/err.h>
5
6int main(int argc, char **argv)
7	{
8	BIO *in = NULL, *out = NULL, *tbio = NULL;
9	X509 *rcert = NULL;
10	STACK_OF(X509) *recips = NULL;
11	PKCS7 *p7 = NULL;
12	int ret = 1;
13
14	/*
15	 * On OpenSSL 0.9.9 only:
16	 * for streaming set PKCS7_STREAM
17	 */
18	int flags = PKCS7_STREAM;
19
20	OpenSSL_add_all_algorithms();
21	ERR_load_crypto_strings();
22
23	/* Read in recipient certificate */
24	tbio = BIO_new_file("signer.pem", "r");
25
26	if (!tbio)
27		goto err;
28
29	rcert = PEM_read_bio_X509(tbio, NULL, 0, NULL);
30
31	if (!rcert)
32		goto err;
33
34	/* Create recipient STACK and add recipient cert to it */
35	recips = sk_X509_new_null();
36
37	if (!recips || !sk_X509_push(recips, rcert))
38		goto err;
39
40	/* sk_X509_pop_free will free up recipient STACK and its contents
41	 * so set rcert to NULL so it isn't freed up twice.
42	 */
43	rcert = NULL;
44
45	/* Open content being encrypted */
46
47	in = BIO_new_file("encr.txt", "r");
48
49	if (!in)
50		goto err;
51
52	/* encrypt content */
53	p7 = PKCS7_encrypt(recips, in, EVP_des_ede3_cbc(), flags);
54
55	if (!p7)
56		goto err;
57
58	out = BIO_new_file("smencr.txt", "w");
59	if (!out)
60		goto err;
61
62	/* Write out S/MIME message */
63	if (!SMIME_write_PKCS7(out, p7, in, flags))
64		goto err;
65
66	ret = 0;
67
68	err:
69
70	if (ret)
71		{
72		fprintf(stderr, "Error Encrypting Data\n");
73		ERR_print_errors_fp(stderr);
74		}
75
76	if (p7)
77		PKCS7_free(p7);
78	if (rcert)
79		X509_free(rcert);
80	if (recips)
81		sk_X509_pop_free(recips, X509_free);
82
83	if (in)
84		BIO_free(in);
85	if (out)
86		BIO_free(out);
87	if (tbio)
88		BIO_free(tbio);
89
90	return ret;
91
92	}
93