1 files changed, 88 insertions, 0 deletions
diff --git a/openssl/demos/smime/smsign.c b/openssl/demos/smime/smsign.c
new file mode 100644
index 0000000..c7bf86d
--- /dev/null
+++ b/openssl/demos/smime/smsign.c
@@ -0,0 +1,88 @@
+/* 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);
+
+    if (in)
+        BIO_free(in);
+    if (out)
+        BIO_free(out);
+    if (tbio)
+        BIO_free(tbio);
+
+    return ret;
+
+}