1 files changed, 140 insertions, 0 deletions
diff --git a/src/libdnssec/key/privkey.c b/src/libdnssec/key/privkey.c
new file mode 100644
index 0000000..abe968a
--- /dev/null
+++ b/src/libdnssec/key/privkey.c
@@ -0,0 +1,140 @@
+/*  Copyright (C) 2018 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <gnutls/abstract.h>
+#include <gnutls/gnutls.h>
+
+#include "libdnssec/binary.h"
+#include "libdnssec/error.h"
+#include "libdnssec/key/algorithm.h"
+#include "libdnssec/key/convert.h"
+#include "libdnssec/key/dnskey.h"
+#include "libdnssec/key/internal.h"
+#include "libdnssec/key/privkey.h"
+#include "libdnssec/shared/shared.h"
+#include "libdnssec/shared/binary_wire.h"
+
+/* -- internal functions --------------------------------------------------- */
+
+/*!
+ * Check if the algorithm number is valid for given DNSKEY.
+ */
+static bool valid_algorithm(dnssec_key_t *key, gnutls_privkey_t privkey)
+{
+	uint8_t current = dnssec_key_get_algorithm(key);
+	int gnu_algorithm = gnutls_privkey_get_pk_algorithm(privkey, NULL);
+
+	return (gnu_algorithm == algorithm_to_gnutls(current));
+}
+
+/*!
+ * Create GnuTLS public key from private key.
+ */
+static int public_from_private(gnutls_privkey_t privkey, gnutls_pubkey_t *pubkey)
+{
+	assert(privkey);
+	assert(pubkey);
+
+	gnutls_pubkey_t new_key = NULL;
+	int result = gnutls_pubkey_init(&new_key);
+	if (result != GNUTLS_E_SUCCESS) {
+		return DNSSEC_ENOMEM;
+	}
+
+	result = gnutls_pubkey_import_privkey(new_key, privkey, 0, 0);
+	if (result != GNUTLS_E_SUCCESS) {
+		gnutls_pubkey_deinit(new_key);
+		return DNSSEC_KEY_IMPORT_ERROR;
+	}
+
+	*pubkey = new_key;
+
+	return DNSSEC_EOK;
+}
+
+/*!
+ * Create public key (GnuTLS and DNSKEY RDATA) from a private key.
+ */
+static int create_public_key(gnutls_privkey_t privkey,
+			     gnutls_pubkey_t *pubkey_ptr,
+			     dnssec_binary_t *rdata)
+{
+	assert(privkey);
+	assert(pubkey_ptr);
+	assert(rdata);
+
+	// crypto public key
+
+	gnutls_pubkey_t pubkey = NULL;
+	int result = public_from_private(privkey, &pubkey);
+	if (result != DNSSEC_EOK) {
+		return result;
+	}
+
+	// dnssec public key
+
+	_cleanup_binary_ dnssec_binary_t rdata_pubkey = { 0 };
+	result = convert_pubkey_to_dnskey(pubkey, &rdata_pubkey);
+	if (result != DNSSEC_EOK) {
+		gnutls_pubkey_deinit(pubkey);
+		return result;
+	}
+
+	size_t rdata_size = DNSKEY_RDATA_OFFSET_PUBKEY + rdata_pubkey.size;
+	result = dnssec_binary_resize(rdata, rdata_size);
+	if (result != DNSSEC_EOK) {
+		gnutls_pubkey_deinit(pubkey);
+		return result;
+	}
+
+	// updated RDATA
+
+	wire_ctx_t wire = binary_init(rdata);
+	wire_ctx_set_offset(&wire, DNSKEY_RDATA_OFFSET_PUBKEY);
+	binary_write(&wire, &rdata_pubkey);
+	assert(wire_ctx_offset(&wire) == rdata->size);
+
+	*pubkey_ptr = pubkey;
+
+	return DNSSEC_EOK;
+}
+
+/* -- internal API --------------------------------------------------------- */
+
+/*!
+ * Load a private key into a DNSSEC key, create a public part if necessary.
+ */
+int key_set_private_key(dnssec_key_t *key, gnutls_privkey_t privkey)
+{
+	assert(key);
+	assert(privkey);
+	assert(key->private_key == NULL);
+
+	if (!valid_algorithm(key, privkey)) {
+		return DNSSEC_INVALID_KEY_ALGORITHM;
+	}
+
+	if (!key->public_key) {
+		int r = create_public_key(privkey, &key->public_key, &key->rdata);
+		if (r != DNSSEC_EOK) {
+			return r;
+		}
+	}
+
+	key->private_key = privkey;
+
+	return DNSSEC_EOK;
+}