1 files changed, 107 insertions, 0 deletions
diff --git a/src/authkey.c b/src/authkey.c
new file mode 100644
index 0000000..761562b
--- /dev/null
+++ b/src/authkey.c
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 2018-2022 Yubico AB. All rights reserved.
+ * Use of this source code is governed by a BSD-style
+ * license that can be found in the LICENSE file.
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include "fido.h"
+
+static int
+parse_authkey(const cbor_item_t *key, const cbor_item_t *val, void *arg)
+{
+	es256_pk_t *authkey = arg;
+
+	if (cbor_isa_uint(key) == false ||
+	    cbor_int_get_width(key) != CBOR_INT_8 ||
+	    cbor_get_uint8(key) != 1) {
+		fido_log_debug("%s: cbor type", __func__);
+		return (0); /* ignore */
+	}
+
+	return (es256_pk_decode(val, authkey));
+}
+
+static int
+fido_dev_authkey_tx(fido_dev_t *dev, int *ms)
+{
+	fido_blob_t	 f;
+	cbor_item_t	*argv[2];
+	int		 r;
+
+	fido_log_debug("%s: dev=%p", __func__, (void *)dev);
+
+	memset(&f, 0, sizeof(f));
+	memset(argv, 0, sizeof(argv));
+
+	/* add command parameters */
+	if ((argv[0] = cbor_encode_pin_opt(dev)) == NULL ||
+	    (argv[1] = cbor_build_uint8(2)) == NULL) {
+		fido_log_debug("%s: cbor_build", __func__);
+		r = FIDO_ERR_INTERNAL;
+		goto fail;
+	}
+
+	/* frame and transmit */
+	if (cbor_build_frame(CTAP_CBOR_CLIENT_PIN, argv, nitems(argv),
+	    &f) < 0 || fido_tx(dev, CTAP_CMD_CBOR, f.ptr, f.len, ms) < 0) {
+		fido_log_debug("%s: fido_tx", __func__);
+		r = FIDO_ERR_TX;
+		goto fail;
+	}
+
+	r = FIDO_OK;
+fail:
+	cbor_vector_free(argv, nitems(argv));
+	free(f.ptr);
+
+	return (r);
+}
+
+static int
+fido_dev_authkey_rx(fido_dev_t *dev, es256_pk_t *authkey, int *ms)
+{
+	unsigned char	*msg;
+	int		 msglen;
+	int		 r;
+
+	fido_log_debug("%s: dev=%p, authkey=%p, ms=%d", __func__, (void *)dev,
+	    (void *)authkey, *ms);
+
+	memset(authkey, 0, sizeof(*authkey));
+
+	if ((msg = malloc(FIDO_MAXMSG)) == NULL) {
+		r = FIDO_ERR_INTERNAL;
+		goto out;
+	}
+
+	if ((msglen = fido_rx(dev, CTAP_CMD_CBOR, msg, FIDO_MAXMSG, ms)) < 0) {
+		fido_log_debug("%s: fido_rx", __func__);
+		r = FIDO_ERR_RX;
+		goto out;
+	}
+
+	r = cbor_parse_reply(msg, (size_t)msglen, authkey, parse_authkey);
+out:
+	freezero(msg, FIDO_MAXMSG);
+
+	return (r);
+}
+
+static int
+fido_dev_authkey_wait(fido_dev_t *dev, es256_pk_t *authkey, int *ms)
+{
+	int r;
+
+	if ((r = fido_dev_authkey_tx(dev, ms)) != FIDO_OK ||
+	    (r = fido_dev_authkey_rx(dev, authkey, ms)) != FIDO_OK)
+		return (r);
+
+	return (FIDO_OK);
+}
+
+int
+fido_dev_authkey(fido_dev_t *dev, es256_pk_t *authkey, int *ms)
+{
+	return (fido_dev_authkey_wait(dev, authkey, ms));
+}