/*
 * Copyright (c) 2018 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.
 */

#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   reply[FIDO_MAXMSG];
        int             reply_len;

        fido_log_debug("%s: dev=%p, authkey=%p, ms=%d", __func__, (void *)dev,
            (void *)authkey, *ms);

        memset(authkey, 0, sizeof(*authkey));

        if ((reply_len = fido_rx(dev, CTAP_CMD_CBOR, &reply, sizeof(reply),
            ms)) < 0) {
                fido_log_debug("%s: fido_rx", __func__);
                return (FIDO_ERR_RX);
        }

        return (cbor_parse_reply(reply, (size_t)reply_len, authkey,
            parse_authkey));
}

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));
}