Detached encrypt/decrypt example, fix decrypt sample.

demos/cms/cms_ddec.c

@@ -0,0 +1,89 @@
+/* S/MIME detached data decrypt example: rarely done but
+ * should the need arise this is an example....
+ */
+#include <openssl/pem.h>
+#include <openssl/cms.h>
+#include <openssl/err.h>
+
+int main(int argc, char **argv)
+	{
+	BIO *in = NULL, *out = NULL, *tbio = NULL, *dcont = NULL;
+	X509 *rcert = NULL;
+	EVP_PKEY *rkey = NULL;
+	CMS_ContentInfo *cms = NULL;
+	int ret = 1;
+
+	OpenSSL_add_all_algorithms();
+	ERR_load_crypto_strings();
+
+	/* Read in recipient certificate and private key */
+	tbio = BIO_new_file("signer.pem", "r");
+
+	if (!tbio)
+		goto err;
+
+	rcert = PEM_read_bio_X509(tbio, NULL, 0, NULL);
+
+	BIO_reset(tbio);
+
+	rkey = PEM_read_bio_PrivateKey(tbio, NULL, 0, NULL);
+
+	if (!rcert || !rkey)
+		goto err;
+
+	/* Open PEM file containing enveloped data */
+
+	in = BIO_new_file("smencr.pem", "r");
+
+	if (!in)
+		goto err;
+
+	/* Parse PEM content */
+	cms = PEM_read_bio_CMS(in, NULL, 0, NULL);
+
+	if (!cms)
+		goto err;
+
+	/* Open file containing detached content */
+	dcont = BIO_new_file("smencr.out", "rb");
+
+	if (!in)
+		goto err;
+
+	out = BIO_new_file("encrout.txt", "w");
+	if (!out)
+		goto err;
+
+	/* Decrypt S/MIME message */
+	if (!CMS_decrypt(cms, rkey, rcert, dcont, out, 0))
+		goto err;
+
+	ret = 0;
+
+	err:
+
+	if (ret)
+		{
+		fprintf(stderr, "Error Decrypting Data\n");
+		ERR_print_errors_fp(stderr);
+		}
+
+	if (cms)
+		CMS_ContentInfo_free(cms);
+	if (rcert)
+		X509_free(rcert);
+	if (rkey)
+		EVP_PKEY_free(rkey);
+
+	if (in)
+		BIO_free(in);
+	if (out)
+		BIO_free(out);
+	if (tbio)
+		BIO_free(tbio);
+	if (dcont)
+		BIO_free(dcont);
+
+	return ret;
+
+	}

demos/cms/cms_dec.c

@@ -29,20 +29,20 @@ int main(int argc, char **argv)
 	if (!rcert || !rkey)
 		goto err;
 
-	/* Open content being signed */
+	/* Open S/MIME message to decrypt */
 
 	in = BIO_new_file("smencr.txt", "r");
 
 	if (!in)
 		goto err;
 
-	/* Sign content */
+	/* Parse message */
 	cms = SMIME_read_CMS(in, NULL);
 
 	if (!cms)
 		goto err;
 
-	out = BIO_new_file("encrout.txt", "w");
+	out = BIO_new_file("decout.txt", "w");
 	if (!out)
 		goto err;
 
@@ -56,7 +56,7 @@ int main(int argc, char **argv)
 
 	if (ret)
 		{
-		fprintf(stderr, "Error Signing Data\n");
+		fprintf(stderr, "Error Decrypting Data\n");
 		ERR_print_errors_fp(stderr);
 		}
 

demos/cms/cms_denc.c

@@ -0,0 +1,97 @@
+/* S/MIME detached data encrypt example: rarely done but
+ * should the need arise this is an example....
+ */
+#include <openssl/pem.h>
+#include <openssl/cms.h>
+#include <openssl/err.h>
+
+int main(int argc, char **argv)
+	{
+	BIO *in = NULL, *out = NULL, *tbio = NULL, *dout = NULL;
+	X509 *rcert = NULL;
+	STACK_OF(X509) *recips = NULL;
+	CMS_ContentInfo *cms = NULL;
+	int ret = 1;
+
+	int flags = CMS_STREAM|CMS_DETACHED;
+
+	OpenSSL_add_all_algorithms();
+	ERR_load_crypto_strings();
+
+	/* Read in recipient certificate */
+	tbio = BIO_new_file("signer.pem", "r");
+
+	if (!tbio)
+		goto err;
+
+	rcert = PEM_read_bio_X509(tbio, NULL, 0, NULL);
+
+	if (!rcert)
+		goto err;
+
+	/* Create recipient STACK and add recipient cert to it */
+	recips = sk_X509_new_null();
+
+	if (!recips || !sk_X509_push(recips, rcert))
+		goto err;
+
+	/* sk_X509_pop_free will free up recipient STACK and its contents
+	 * so set rcert to NULL so it isn't freed up twice.
+	 */
+	rcert = NULL;
+
+	/* Open content being encrypted */
+
+	in = BIO_new_file("encr.txt", "r");
+
+	dout = BIO_new_file("smencr.out", "wb");
+
+	if (!in)
+		goto err;
+
+	/* encrypt content */
+	cms = CMS_encrypt(recips, in, EVP_des_ede3_cbc(), flags);
+
+	if (!cms)
+		goto err;
+
+	out = BIO_new_file("smencr.pem", "w");
+	if (!out)
+		goto err;
+
+	if (!CMS_final(cms, in, dout, flags))
+		goto err;
+
+	/* Write out CMS structure without content */
+	if (!PEM_write_bio_CMS(out, cms))
+		goto err;
+
+	ret = 0;
+
+	err:
+
+	if (ret)
+		{
+		fprintf(stderr, "Error Encrypting Data\n");
+		ERR_print_errors_fp(stderr);
+		}
+
+	if (cms)
+		CMS_ContentInfo_free(cms);
+	if (rcert)
+		X509_free(rcert);
+	if (recips)
+		sk_X509_pop_free(recips, X509_free);
+
+	if (in)
+		BIO_free(in);
+	if (out)
+		BIO_free(out);
+	if (dout)
+		BIO_free(dout);
+	if (tbio)
+		BIO_free(tbio);
+
+	return ret;
+
+	}