1 /* Simple S/MIME verification example */
2 #include <openssl/pem.h>
3 #include <openssl/pkcs7.h>
4 #include <openssl/err.h>
5
main(int argc,char ** argv)6 int main(int argc, char **argv)
7 {
8 BIO *in = NULL, *out = NULL, *tbio = NULL, *cont = NULL;
9 X509_STORE *st = NULL;
10 X509 *cacert = NULL;
11 PKCS7 *p7 = NULL;
12
13 int ret = 1;
14
15 OpenSSL_add_all_algorithms();
16 ERR_load_crypto_strings();
17
18 /* Set up trusted CA certificate store */
19
20 st = X509_STORE_new();
21
22 /* Read in signer certificate and private key */
23 tbio = BIO_new_file("cacert.pem", "r");
24
25 if (!tbio)
26 goto err;
27
28 cacert = PEM_read_bio_X509(tbio, NULL, 0, NULL);
29
30 if (!cacert)
31 goto err;
32
33 if (!X509_STORE_add_cert(st, cacert))
34 goto err;
35
36 /* Open content being signed */
37
38 in = BIO_new_file("smout.txt", "r");
39
40 if (!in)
41 goto err;
42
43 /* Sign content */
44 p7 = SMIME_read_PKCS7(in, &cont);
45
46 if (!p7)
47 goto err;
48
49 /* File to output verified content to */
50 out = BIO_new_file("smver.txt", "w");
51 if (!out)
52 goto err;
53
54 if (!PKCS7_verify(p7, NULL, st, cont, out, 0)) {
55 fprintf(stderr, "Verification Failure\n");
56 goto err;
57 }
58
59 fprintf(stderr, "Verification Successful\n");
60
61 ret = 0;
62
63 err:
64
65 if (ret) {
66 fprintf(stderr, "Error Verifying Data\n");
67 ERR_print_errors_fp(stderr);
68 }
69
70 if (p7)
71 PKCS7_free(p7);
72
73 if (cacert)
74 X509_free(cacert);
75
76 if (in)
77 BIO_free(in);
78 if (out)
79 BIO_free(out);
80 if (tbio)
81 BIO_free(tbio);
82
83 return ret;
84
85 }
86