1 /*
2 * S/MIME detached data decrypt 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, *dcont = NULL;
12 X509 *rcert = NULL;
13 EVP_PKEY *rkey = NULL;
14 CMS_ContentInfo *cms = NULL;
15 int ret = 1;
16
17 OpenSSL_add_all_algorithms();
18 ERR_load_crypto_strings();
19
20 /* Read in recipient certificate and private key */
21 tbio = BIO_new_file("signer.pem", "r");
22
23 if (!tbio)
24 goto err;
25
26 rcert = PEM_read_bio_X509(tbio, NULL, 0, NULL);
27
28 BIO_reset(tbio);
29
30 rkey = PEM_read_bio_PrivateKey(tbio, NULL, 0, NULL);
31
32 if (!rcert || !rkey)
33 goto err;
34
35 /* Open PEM file containing enveloped data */
36
37 in = BIO_new_file("smencr.pem", "r");
38
39 if (!in)
40 goto err;
41
42 /* Parse PEM content */
43 cms = PEM_read_bio_CMS(in, NULL, 0, NULL);
44
45 if (!cms)
46 goto err;
47
48 /* Open file containing detached content */
49 dcont = BIO_new_file("smencr.out", "rb");
50
51 if (!in)
52 goto err;
53
54 out = BIO_new_file("encrout.txt", "w");
55 if (!out)
56 goto err;
57
58 /* Decrypt S/MIME message */
59 if (!CMS_decrypt(cms, rkey, rcert, dcont, out, 0))
60 goto err;
61
62 ret = 0;
63
64 err:
65
66 if (ret) {
67 fprintf(stderr, "Error Decrypting Data\n");
68 ERR_print_errors_fp(stderr);
69 }
70
71 if (cms)
72 CMS_ContentInfo_free(cms);
73 if (rcert)
74 X509_free(rcert);
75 if (rkey)
76 EVP_PKEY_free(rkey);
77
78 if (in)
79 BIO_free(in);
80 if (out)
81 BIO_free(out);
82 if (tbio)
83 BIO_free(tbio);
84 if (dcont)
85 BIO_free(dcont);
86
87 return ret;
88
89 }
90