1 /*
2 * S/MIME detached data encrypt example: rarely done but should the need
3 * arise this is an example....
4 */
5 #include <openssl/pem.h>
6 #include <openssl/cms.h>
7 #include <openssl/err.h>
8
main(int argc,char ** argv)9 int main(int argc, char **argv)
10 {
11 BIO *in = NULL, *out = NULL, *tbio = NULL, *dout = NULL;
12 X509 *rcert = NULL;
13 STACK_OF(X509) *recips = NULL;
14 CMS_ContentInfo *cms = NULL;
15 int ret = 1;
16
17 int flags = CMS_STREAM | CMS_DETACHED;
18
19 OpenSSL_add_all_algorithms();
20 ERR_load_crypto_strings();
21
22 /* Read in recipient certificate */
23 tbio = BIO_new_file("signer.pem", "r");
24
25 if (!tbio)
26 goto err;
27
28 rcert = PEM_read_bio_X509(tbio, NULL, 0, NULL);
29
30 if (!rcert)
31 goto err;
32
33 /* Create recipient STACK and add recipient cert to it */
34 recips = sk_X509_new_null();
35
36 if (!recips || !sk_X509_push(recips, rcert))
37 goto err;
38
39 /*
40 * sk_X509_pop_free will free up recipient STACK and its contents so set
41 * 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 dout = BIO_new_file("smencr.out", "wb");
50
51 if (!in)
52 goto err;
53
54 /* encrypt content */
55 cms = CMS_encrypt(recips, in, EVP_des_ede3_cbc(), flags);
56
57 if (!cms)
58 goto err;
59
60 out = BIO_new_file("smencr.pem", "w");
61 if (!out)
62 goto err;
63
64 if (!CMS_final(cms, in, dout, flags))
65 goto err;
66
67 /* Write out CMS structure without content */
68 if (!PEM_write_bio_CMS(out, cms))
69 goto err;
70
71 ret = 0;
72
73 err:
74
75 if (ret) {
76 fprintf(stderr, "Error Encrypting Data\n");
77 ERR_print_errors_fp(stderr);
78 }
79
80 if (cms)
81 CMS_ContentInfo_free(cms);
82 if (rcert)
83 X509_free(rcert);
84 if (recips)
85 sk_X509_pop_free(recips, X509_free);
86
87 if (in)
88 BIO_free(in);
89 if (out)
90 BIO_free(out);
91 if (dout)
92 BIO_free(dout);
93 if (tbio)
94 BIO_free(tbio);
95
96 return ret;
97
98 }
99