text: /*
   * Copyright (c) 2020 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 <openssl/sha.h>
  
  #include "fido.h"
  #include "fido/es256.h"
  
  #define LARGEBLOB_DIGEST_LENGTH	16
  #define LARGEBLOB_NONCE_LENGTH	12
  #define LARGEBLOB_TAG_LENGTH	16
  
  typedef struct largeblob {
  	size_t origsiz;
  	fido_blob_t ciphertext;
  	fido_blob_t nonce;
  } largeblob_t;
  
  static largeblob_t *
  largeblob_new(void)
  {
  	return calloc(1, sizeof(largeblob_t));
  }
  
  static void
  largeblob_reset(largeblob_t *blob)
  {
  	fido_blob_reset(&blob->ciphertext);
  	fido_blob_reset(&blob->nonce);
  	blob->origsiz = 0;
  }
  
  static void
  largeblob_free(largeblob_t **blob_ptr)
  {
  	largeblob_t *blob;
  
  	if (blob_ptr == NULL || (blob = *blob_ptr) == NULL)
  		return;
  	largeblob_reset(blob);
  	free(blob);
  	*blob_ptr = NULL;
  }
  
  static int
  largeblob_aad(fido_blob_t *aad, uint64_t size)
  {
  	uint8_t buf[4 + sizeof(uint64_t)];
  
  	buf[0] = 0x62; /* b */
  	buf[1] = 0x6c; /* l */
  	buf[2] = 0x6f; /* o */
  	buf[3] = 0x62; /* b */
  	size = htole64(size);
  	memcpy(&buf[4], &size, sizeof(uint64_t));
  
  	return fido_blob_set(aad, buf, sizeof(buf));
  }
  
  static fido_blob_t *
  largeblob_decrypt(const largeblob_t *blob, const fido_blob_t *key)
  {
  	fido_blob_t *plaintext = NULL, *aad = NULL;
  	int ok = -1;
  
  	if ((plaintext = fido_blob_new()) == NULL ||
  	    (aad = fido_blob_new()) == NULL) {
  		fido_log_debug("%s: fido_blob_new", __func__);
  		goto fail;
  	}
  	if (largeblob_aad(aad, blob->origsiz) < 0) {
  		fido_log_debug("%s: largeblob_aad", __func__);
  		goto fail;
  	}
  	if (aes256_gcm_dec(key, &blob->nonce, aad, &blob->ciphertext,
  	    plaintext) < 0) {
  		fido_log_debug("%s: aes256_gcm_dec", __func__);
  		goto fail;
  	}
  
  	ok = 0;
  fail:
  	fido_blob_free(&aad);
  
  	if (ok < 0)
  		fido_blob_free(&plaintext);
  
  	return plaintext;
  }
  
  static int
  largeblob_get_nonce(largeblob_t *blob)
  {
  	uint8_t buf[LARGEBLOB_NONCE_LENGTH];
  	int ok = -1;
  
  	if (fido_get_random(buf, sizeof(buf)) < 0) {
  		fido_log_debug("%s: fido_get_random", __func__);
  		goto fail;
  	}
  	if (fido_blob_set(&blob->nonce, buf, sizeof(buf)) < 0) {
  		fido_log_debug("%s: fido_blob_set", __func__);
  		goto fail;
  	}
  
  	ok = 0;
  fail:
  	explicit_bzero(buf, sizeof(buf));
  
  	return ok;
  }
  
  static int
  largeblob_seal(largeblob_t *blob, const fido_blob_t *body,
      const fido_blob_t *key)
  {
  	fido_blob_t *plaintext = NULL, *aad = NULL;
  	int ok = -1;
  
  	if ((plaintext = fido_blob_new()) == NULL ||
  	    (aad = fido_blob_new()) == NULL) {
  		fido_log_debug("%s: fido_blob_new", __func__);
  		goto fail;
  	}
  	if (fido_compress(plaintext, body) != FIDO_OK) {
  		fido_log_debug("%s: fido_compress", __func__);
  		goto fail;
  	}
  	if (largeblob_aad(aad, body->len) < 0) {
  		fido_log_debug("%s: largeblob_aad", __func__);
  		goto fail;
  	}
  	if (largeblob_get_nonce(blob) < 0) {
  		fido_log_debug("%s: largeblob_get_nonce", __func__);
  		goto fail;
  	}
  	if (aes256_gcm_enc(key, &blob->nonce, aad, plaintext,
  	    &blob->ciphertext) < 0) {
  		fido_log_debug("%s: aes256_gcm_enc", __func__);
  		goto fail;
  	}
  	blob->origsiz = body->len;
  
  	ok = 0;
  fail:
  	fido_blob_free(&plaintext);
  	fido_blob_free(&aad);
  
  	return ok;
  }
  
  static int
  largeblob_get_tx(fido_dev_t *dev, size_t offset, size_t count)
  {
  	fido_blob_t f;
  	cbor_item_t *argv[3];
  	int r;
  
  	memset(argv, 0, sizeof(argv));
  	memset(&f, 0, sizeof(f));
  
  	if ((argv[0] = cbor_build_uint(count)) == NULL ||
  	    (argv[2] = cbor_build_uint(offset)) == NULL) {
  		fido_log_debug("%s: cbor encode", __func__);
  		r = FIDO_ERR_INTERNAL;
  		goto fail;
  	}
  	if (cbor_build_frame(CTAP_CBOR_LARGEBLOB, argv, nitems(argv), &f) < 0 ||
  	    fido_tx(dev, CTAP_CMD_CBOR, f.ptr, f.len) < 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
  parse_largeblob_reply(const cbor_item_t *key, const cbor_item_t *val,
      void *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 fido_blob_decode(val, arg);
  }
  
  static int
  largeblob_get_rx(fido_dev_t *dev, fido_blob_t **chunk, int ms)
  {
  	unsigned char reply[FIDO_MAXMSG];
  	int reply_len, r;
  
  	*chunk = NULL;
  	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;
  	}
  	if ((*chunk = fido_blob_new()) == NULL) {
  		fido_log_debug("%s: fido_blob_new", __func__);
  		return FIDO_ERR_INTERNAL;
  	}
  	if ((r = cbor_parse_reply(reply, (size_t)reply_len, *chunk,
  	    parse_largeblob_reply)) != FIDO_OK) {
  		fido_log_debug("%s: parse_largeblob_reply", __func__);
  		fido_blob_free(chunk);
  		return r;
  	}
  
  	return FIDO_OK;
  }
  
  static cbor_item_t *
  largeblob_array_load(const uint8_t *ptr, size_t len)
  {
  	struct cbor_load_result cbor;
  	cbor_item_t *item;
  
  	if (len < LARGEBLOB_DIGEST_LENGTH) {
  		fido_log_debug("%s: len", __func__);
  		return NULL;
  	}
  	len -= LARGEBLOB_DIGEST_LENGTH;
  	if ((item = cbor_load(ptr, len, &cbor)) == NULL) {
  		fido_log_debug("%s: cbor_load", __func__);
  		return NULL;
  	}
  	if (!cbor_isa_array(item) || !cbor_array_is_definite(item)) {
  		fido_log_debug("%s: cbor type", __func__);
  		cbor_decref(&item);
  		return NULL;
  	}
  
  	return item;
  }
  
  static size_t
  get_chunklen(fido_dev_t *dev)
  {
  	uint64_t maxchunklen;
  
  	if ((maxchunklen = fido_dev_maxmsgsize(dev)) > SIZE_MAX)
  		maxchunklen = SIZE_MAX;
  	if (maxchunklen > FIDO_MAXMSG)
  		maxchunklen = FIDO_MAXMSG;
  	maxchunklen = maxchunklen > 64 ? maxchunklen - 64 : 0;
  
  	return (size_t)maxchunklen;
  }
  
  static int
  largeblob_do_decode(const cbor_item_t *key, const cbor_item_t *val, void *arg)
  {
  	largeblob_t *blob = arg;
  	uint64_t origsiz;
  
  	if (cbor_isa_uint(key) == false ||
  	    cbor_int_get_width(key) != CBOR_INT_8) {
  		fido_log_debug("%s: cbor type", __func__);
  		return 0; /* ignore */
  	}
  
  	switch (cbor_get_uint8(key)) {
  	case 1: /* ciphertext */
  		if (fido_blob_decode(val, &blob->ciphertext) < 0 ||
  		    blob->ciphertext.len < LARGEBLOB_TAG_LENGTH)
  			return -1;
  		return 0;
  	case 2: /* nonce */
  		if (fido_blob_decode(val, &blob->nonce) < 0 ||
  		    blob->nonce.len != LARGEBLOB_NONCE_LENGTH)
  			return -1;
  		return 0;
  	case 3: /* origSize */
  		if (!cbor_isa_uint(val) ||
  		    (origsiz = cbor_get_int(val)) > SIZE_MAX)
  			return -1;
  		blob->origsiz = (size_t)origsiz;
  		return 0;
  	default: /* ignore */
  		fido_log_debug("%s: cbor type", __func__);
  		return 0;
  	}
  }
  
  static int
  largeblob_decode(largeblob_t *blob, const cbor_item_t *item)
  {
  	if (!cbor_isa_map(item) || !cbor_map_is_definite(item)) {
  		fido_log_debug("%s: cbor type", __func__);
  		return -1;
  	}
  	if (cbor_map_iter(item, blob, largeblob_do_decode) < 0) {
  		fido_log_debug("%s: cbor_map_iter", __func__);
  		return -1;
  	}
  	if (fido_blob_is_empty(&blob->ciphertext) ||
  	    fido_blob_is_empty(&blob->nonce) || blob->origsiz == 0) {
  		fido_log_debug("%s: incomplete blob", __func__);
  		return -1;
  	}
  
  	return 0;
  }
  
  static cbor_item_t *
  largeblob_encode(const fido_blob_t *body, const fido_blob_t *key)
  {
  	largeblob_t *blob;
  	cbor_item_t *argv[3], *item = NULL;
  
  	memset(argv, 0, sizeof(argv));
  	if ((blob = largeblob_new()) == NULL ||
  	    largeblob_seal(blob, body, key) < 0) {
  		fido_log_debug("%s: largeblob_seal", __func__);
  		goto fail;
  	}
  	if ((argv[0] = fido_blob_encode(&blob->ciphertext)) == NULL ||
  	    (argv[1] = fido_blob_encode(&blob->nonce)) == NULL ||
  	    (argv[2] = cbor_build_uint(blob->origsiz)) == NULL) {
  		fido_log_debug("%s: cbor encode", __func__);
  		goto fail;
  	}
  	item = cbor_flatten_vector(argv, nitems(argv));
  fail:
  	cbor_vector_free(argv, nitems(argv));
  	largeblob_free(&blob);
  
  	return item;
  }
  
  static int
  largeblob_array_lookup(fido_blob_t *out, size_t *idx, const cbor_item_t *item,
      const fido_blob_t *key)
  {
  	cbor_item_t **v;
  	fido_blob_t *plaintext = NULL;
  	largeblob_t blob;
  	int r;
  
  	memset(&blob, 0, sizeof(blob));
  	if (idx != NULL)
  		*idx = 0;
  	if ((v = cbor_array_handle(item)) == NULL)
  		return FIDO_ERR_INVALID_ARGUMENT;
  	for (size_t i = 0; i < cbor_array_size(item); i++) {
  		if (largeblob_decode(&blob, v[i]) < 0 ||
  		    (plaintext = largeblob_decrypt(&blob, key)) == NULL) {
  			fido_log_debug("%s: largeblob_decode", __func__);
  			largeblob_reset(&blob);
  			continue;
  		}
  		if (idx != NULL)
  			*idx = i;
  		break;
  	}
  	if (plaintext == NULL) {
  		fido_log_debug("%s: not found", __func__);
  		return FIDO_ERR_NOTFOUND;
  	}
  	if (out != NULL)
  		r = fido_uncompress(out, plaintext, blob.origsiz);
  	else
  		r = FIDO_OK;
  
  	fido_blob_free(&plaintext);
  	largeblob_reset(&blob);
  
  	return r;
  }
  
  static int
  largeblob_array_digest(u_char out[LARGEBLOB_DIGEST_LENGTH], const u_char *data,
      size_t len)
  {
  	u_char dgst[SHA256_DIGEST_LENGTH];
  
  	if (data == NULL || len == 0)
  		return -1;
  	if (SHA256(data, len, dgst) != dgst)
  		return -1;
  	memcpy(out, dgst, LARGEBLOB_DIGEST_LENGTH);
  
  	return 0;
  }
  
  static int
  largeblob_array_check(const fido_blob_t *array)
  {
  	u_char expected_hash[LARGEBLOB_DIGEST_LENGTH];
  	size_t body_len;
  
  	fido_log_xxd(array->ptr, array->len, __func__);
  	if (array->len < sizeof(expected_hash)) {
  		fido_log_debug("%s: len %zu", __func__, array->len);
  		return -1;
  	}
  	body_len = array->len - sizeof(expected_hash);
  	if (largeblob_array_digest(expected_hash, array->ptr, body_len) < 0) {
  		fido_log_debug("%s: largeblob_array_digest", __func__);
  		return -1;
  	}
  
  	return timingsafe_bcmp(expected_hash, array->ptr + body_len,
  	    sizeof(expected_hash));
  }
  
  static int
  largeblob_get_array(fido_dev_t *dev, cbor_item_t **item)
  {
  	fido_blob_t *array, *chunk = NULL;
  	size_t n;
  	int r;
  
  	*item = NULL;
  	if ((n = get_chunklen(dev)) == 0)
  		return FIDO_ERR_INVALID_ARGUMENT;
  	if ((array = fido_blob_new()) == NULL)
  		return FIDO_ERR_INTERNAL;
  	do {
  		fido_blob_free(&chunk);
  		if ((r = largeblob_get_tx(dev, array->len, n)) != FIDO_OK ||
  		    (r = largeblob_get_rx(dev, &chunk, -1)) != FIDO_OK) {
  			fido_log_debug("%s: largeblob_get_wait %zu/%zu",
  			    __func__, array->len, n);
  			goto fail;
  		}
  		if (fido_blob_append(array, chunk->ptr, chunk->len) < 0) {
  			fido_log_debug("%s: fido_blob_append", __func__);
  			r = FIDO_ERR_INTERNAL;
  			goto fail;
  		}
  	} while (chunk->len == n);
  
  	if (largeblob_array_check(array) != 0)
  		*item = cbor_new_definite_array(0); /* per spec */
  	else
  		*item = largeblob_array_load(array->ptr, array->len);
  	if (*item == NULL)
  		r = FIDO_ERR_INTERNAL;
  	else
  		r = FIDO_OK;
  fail:
  	fido_blob_free(&array);
  	fido_blob_free(&chunk);
  
  	return r;
  }
  
  static int
  prepare_hmac(size_t offset, const u_char *data, size_t len, fido_blob_t *hmac)
  {
  	uint8_t buf[32 + 2 + sizeof(uint32_t) + SHA256_DIGEST_LENGTH];
  	uint32_t u32_offset;
  
  	if (data == NULL || len == 0) {
  		fido_log_debug("%s: invalid data=%p, len=%zu", __func__,
  		    (const void *)data, len);
  		return -1;
  	}
  	if (offset > UINT32_MAX) {
  		fido_log_debug("%s: invalid offset=%zu", __func__, offset);
  		return -1;
  	}
  
  	memset(buf, 0xff, 32);
  	buf[32] = CTAP_CBOR_LARGEBLOB;
  	buf[33] = 0x00;
  	u32_offset = htole32((uint32_t)offset);
  	memcpy(&buf[34], &u32_offset, sizeof(uint32_t));
  	if (SHA256(data, len, &buf[38]) != &buf[38]) {
  		fido_log_debug("%s: SHA256", __func__);
  		return -1;
  	}
  
  	return fido_blob_set(hmac, buf, sizeof(buf));
  }
  
  static int
  largeblob_set_tx(fido_dev_t *dev, const fido_blob_t *token, const u_char *chunk,
      size_t chunk_len, size_t offset, size_t totalsiz)
  {
  	fido_blob_t *hmac = NULL, f;
  	cbor_item_t *argv[6];
  	int r;
  
  	memset(argv, 0, sizeof(argv));
  	memset(&f, 0, sizeof(f));
  
  	if ((argv[1] = cbor_build_bytestring(chunk, chunk_len)) == NULL ||
  	    (argv[2] = cbor_build_uint(offset)) == NULL ||
  	    (offset == 0 && (argv[3] = cbor_build_uint(totalsiz)) == NULL)) {
  		fido_log_debug("%s: cbor encode", __func__);
  		r = FIDO_ERR_INTERNAL;
  		goto fail;
  	}
  	if (token != NULL) {
  		if ((hmac = fido_blob_new()) == NULL ||
  		    prepare_hmac(offset, chunk, chunk_len, hmac) < 0 ||
  		    (argv[4] = cbor_encode_pin_auth(dev, token, hmac)) == NULL ||
  		    (argv[5] = cbor_encode_pin_opt(dev)) == NULL) {
  			fido_log_debug("%s: cbor_encode_pin_auth", __func__);
  			r = FIDO_ERR_INTERNAL;
  			goto fail;
  		}
  	}
  	if (cbor_build_frame(CTAP_CBOR_LARGEBLOB, argv, nitems(argv), &f) < 0 ||
  	    fido_tx(dev, CTAP_CMD_CBOR, f.ptr, f.len) < 0) {
  		fido_log_debug("%s: fido_tx", __func__);
  		r = FIDO_ERR_TX;
  		goto fail;
  	}
  
  	r = FIDO_OK;
  fail:
  	cbor_vector_free(argv, nitems(argv));
  	fido_blob_free(&hmac);
  	free(f.ptr);
  
  	return r;
  }
  
  static int
  largeblob_get_uv_token(fido_dev_t *dev, const char *pin, fido_blob_t **token)
  {
  	es256_pk_t *pk = NULL;
  	fido_blob_t *ecdh = NULL;
  	int r;
  
  	*token = NULL;
  	if ((*token = fido_blob_new()) == NULL)
  		return FIDO_ERR_INTERNAL;
  	if ((r = fido_do_ecdh(dev, &pk, &ecdh)) != FIDO_OK) {
  		fido_log_debug("%s: fido_do_ecdh", __func__);
  		goto fail;
  	}
  	if ((r = fido_dev_get_uv_token(dev, CTAP_CBOR_LARGEBLOB, pin, ecdh, pk,
  	    NULL, *token)) != FIDO_OK) {
  		fido_log_debug("%s: fido_dev_get_uv_token", __func__);
  		goto fail;
  	}
  
  	r = FIDO_OK;
  fail:
  	if (r != FIDO_OK)
  		fido_blob_free(token);
  
  	fido_blob_free(&ecdh);
  	es256_pk_free(&pk);
  
  	return r;
  }
  
  static int
  largeblob_set_array(fido_dev_t *dev, const cbor_item_t *item, const char *pin)
  {
  	unsigned char dgst[SHA256_DIGEST_LENGTH];
  	fido_blob_t cbor, *token = NULL;
  	size_t chunklen, maxchunklen, totalsize;
  	int r;
  
  	memset(&cbor, 0, sizeof(cbor));
  
  	if ((maxchunklen = get_chunklen(dev)) == 0) {
  		fido_log_debug("%s: maxchunklen=%zu", __func__, maxchunklen);
  		r = FIDO_ERR_INVALID_ARGUMENT;
  		goto fail;
  	}
  	if (!cbor_isa_array(item) || !cbor_array_is_definite(item)) {
  		fido_log_debug("%s: cbor type", __func__);
  		r = FIDO_ERR_INVALID_ARGUMENT;
  		goto fail;
  	}
  	if ((fido_blob_serialise(&cbor, item)) < 0) {
  		fido_log_debug("%s: fido_blob_serialise", __func__);
  		r = FIDO_ERR_INTERNAL;
  		goto fail;
  	}
  	if (cbor.len > SIZE_MAX - sizeof(dgst)) {
  		fido_log_debug("%s: cbor.len=%zu", __func__, cbor.len);
  		r = FIDO_ERR_INVALID_ARGUMENT;
  		goto fail;
  	}
  	if (SHA256(cbor.ptr, cbor.len, dgst) != dgst) {
  		fido_log_debug("%s: SHA256", __func__);
  		r = FIDO_ERR_INTERNAL;
  		goto fail;
  	}
  	totalsize = cbor.len + sizeof(dgst) - 16; /* the first 16 bytes only */
  	if (fido_dev_can_get_uv_token(dev, pin, FIDO_OPT_OMIT) == true &&
  	    (r = largeblob_get_uv_token(dev, pin, &token)) != FIDO_OK) {
  		fido_log_debug("%s: largeblob_get_uv_token", __func__);
  		goto fail;
  	}
  	for (size_t offset = 0; offset < cbor.len; offset += chunklen) {
  		if ((chunklen = cbor.len - offset) > maxchunklen)
  			chunklen = maxchunklen;
  		if ((r = largeblob_set_tx(dev, token, cbor.ptr + offset,
  		    chunklen, offset, totalsize)) != FIDO_OK ||
  		    (r = fido_rx_cbor_status(dev, -1)) != FIDO_OK) {
  			fido_log_debug("%s: body", __func__);
  			goto fail;
  		}
  	}
  	if ((r = largeblob_set_tx(dev, token, dgst, sizeof(dgst) - 16, cbor.len,
  	    totalsize)) != FIDO_OK ||
  	    (r = fido_rx_cbor_status(dev, -1)) != FIDO_OK) {
  		fido_log_debug("%s: dgst", __func__);
  		goto fail;
  	}
  
  	r = FIDO_OK;
  fail:
  	fido_blob_free(&token);
  	fido_blob_reset(&cbor);
  
  	return r;
  }
  
  static int
  largeblob_add(fido_dev_t *dev, const fido_blob_t *key, cbor_item_t *item,
      const char *pin)
  {
  	cbor_item_t *array = NULL;
  	size_t idx;
  	int r;
  
  	if ((r = largeblob_get_array(dev, &array)) != FIDO_OK) {
  		fido_log_debug("%s: largeblob_get_array", __func__);
  		goto fail;
  	}
  
  	switch (r = largeblob_array_lookup(NULL, &idx, array, key)) {
  	case FIDO_OK:
  		if (!cbor_array_replace(array, idx, item)) {
  			r = FIDO_ERR_INTERNAL;
  			goto fail;
  		}
  		break;
  	case FIDO_ERR_NOTFOUND:
  		if (cbor_array_append(&array, item) < 0) {
  			r = FIDO_ERR_INTERNAL;
  			goto fail;
  		}
  		break;
  	default:
  		fido_log_debug("%s: largeblob_array_lookup", __func__);
  		goto fail;
  	}
  
  	if ((r = largeblob_set_array(dev, array, pin)) != FIDO_OK) {
  		fido_log_debug("%s: largeblob_set_array", __func__);
  		goto fail;
  	}
  
  	r = FIDO_OK;
  fail:
  	if (array != NULL)
  		cbor_decref(&array);
  
  	return r;
  }
  
  static int
  largeblob_drop(fido_dev_t *dev, const fido_blob_t *key, const char *pin)
  {
  	cbor_item_t *array = NULL;
  	size_t idx;
  	int r;
  
  	if ((r = largeblob_get_array(dev, &array)) != FIDO_OK) {
  		fido_log_debug("%s: largeblob_get_array", __func__);
  		goto fail;
  	}
  	if ((r = largeblob_array_lookup(NULL, &idx, array, key)) != FIDO_OK) {
  		fido_log_debug("%s: largeblob_array_lookup", __func__);
  		goto fail;
  	}
  	if (cbor_array_drop(&array, idx) < 0) {
  		fido_log_debug("%s: cbor_array_drop", __func__);
  		r = FIDO_ERR_INTERNAL;
  		goto fail;
  	}
  	if ((r = largeblob_set_array(dev, array, pin)) != FIDO_OK) {
  		fido_log_debug("%s: largeblob_set_array", __func__);
  		goto fail;
  	}
  
  	r = FIDO_OK;
  fail:
  	if (array != NULL)
  		cbor_decref(&array);
  
  	return r;
  }
  
  int
  fido_dev_largeblob_get(fido_dev_t *dev, const unsigned char *key_ptr,
      size_t key_len, unsigned char **blob_ptr, size_t *blob_len)
  {
  	cbor_item_t *item = NULL;
  	fido_blob_t key, body;
  	int r;
  
  	memset(&key, 0, sizeof(key));
  	memset(&body, 0, sizeof(body));
  
  	if (key_len != 32) {
  		fido_log_debug("%s: invalid key len %zu", __func__, key_len);
  		return FIDO_ERR_INVALID_ARGUMENT;
  	}
  	if (blob_ptr == NULL || blob_len == NULL) {
  		fido_log_debug("%s: invalid blob_ptr=%p, blob_len=%p", __func__,
  		    (const void *)blob_ptr, (const void *)blob_len);
  		return FIDO_ERR_INVALID_ARGUMENT;
  	}
  	*blob_ptr = NULL;
  	*blob_len = 0;
  	if (fido_blob_set(&key, key_ptr, key_len) < 0) {
  		fido_log_debug("%s: fido_blob_set", __func__);
  		return FIDO_ERR_INTERNAL;
  	}
  	if ((r = largeblob_get_array(dev, &item)) != FIDO_OK) {
  		fido_log_debug("%s: largeblob_get_array", __func__);
  		goto fail;
  	}
  	if ((r = largeblob_array_lookup(&body, NULL, item, &key)) != FIDO_OK)
  		fido_log_debug("%s: largeblob_array_lookup", __func__);
  	else {
  		*blob_ptr = body.ptr;
  		*blob_len = body.len;
  	}
  fail:
  	if (item != NULL)
  		cbor_decref(&item);
  
  	fido_blob_reset(&key);
  
  	return r;
  }
  
  int
  fido_dev_largeblob_set(fido_dev_t *dev, const unsigned char *key_ptr,
      size_t key_len, const unsigned char *blob_ptr, size_t blob_len,
      const char *pin)
  {
  	cbor_item_t *item = NULL;
  	fido_blob_t key, body;
  	int r;
  
  	memset(&key, 0, sizeof(key));
  	memset(&body, 0, sizeof(body));
  
  	if (key_len != 32) {
  		fido_log_debug("%s: invalid key len %zu", __func__, key_len);
  		return FIDO_ERR_INVALID_ARGUMENT;
  	}
  	if (blob_ptr == NULL || blob_len == 0) {
  		fido_log_debug("%s: invalid blob_ptr=%p, blob_len=%zu", __func__,
  		    (const void *)blob_ptr, blob_len);
  		return FIDO_ERR_INVALID_ARGUMENT;
  	}
  	if (fido_blob_set(&key, key_ptr, key_len) < 0 ||
  	    fido_blob_set(&body, blob_ptr, blob_len) < 0) {
  		fido_log_debug("%s: fido_blob_set", __func__);
  		r = FIDO_ERR_INTERNAL;
  		goto fail;
  	}
  	if ((item = largeblob_encode(&body, &key)) == NULL) {
  		fido_log_debug("%s: largeblob_encode", __func__);
  		r = FIDO_ERR_INTERNAL;
  		goto fail;
  	}
  	if ((r = largeblob_add(dev, &key, item, pin)) != FIDO_OK)
  		fido_log_debug("%s: largeblob_add", __func__);
  fail:
  	if (item != NULL)
  		cbor_decref(&item);
  
  	fido_blob_reset(&key);
  	fido_blob_reset(&body);
  
  	return r;
  }
  
  int
  fido_dev_largeblob_remove(fido_dev_t *dev, const unsigned char *key_ptr,
      size_t key_len, const char *pin)
  {
  	fido_blob_t key;
  	int r;
  
  	memset(&key, 0, sizeof(key));
  
  	if (key_len != 32) {
  		fido_log_debug("%s: invalid key len %zu", __func__, key_len);
  		return FIDO_ERR_INVALID_ARGUMENT;
  	}
  	if (fido_blob_set(&key, key_ptr, key_len) < 0) {
  		fido_log_debug("%s: fido_blob_set", __func__);
  		return FIDO_ERR_INTERNAL;
  	}
  	if ((r = largeblob_drop(dev, &key, pin)) != FIDO_OK)
  		fido_log_debug("%s: largeblob_drop", __func__);
  
  	fido_blob_reset(&key);
  
  	return r;
  }
  
  int
  fido_dev_largeblob_get_array(fido_dev_t *dev, unsigned char **cbor_ptr,
      size_t *cbor_len)
  {
  	cbor_item_t *item = NULL;
  	fido_blob_t cbor;
  	int r;
  
  	memset(&cbor, 0, sizeof(cbor));
  
  	if (cbor_ptr == NULL || cbor_len == NULL) {
  		fido_log_debug("%s: invalid cbor_ptr=%p, cbor_len=%p", __func__,
  		    (const void *)cbor_ptr, (const void *)cbor_len);
  		return FIDO_ERR_INVALID_ARGUMENT;
  	}
  	*cbor_ptr = NULL;
  	*cbor_len = 0;
  	if ((r = largeblob_get_array(dev, &item)) != FIDO_OK) {
  		fido_log_debug("%s: largeblob_get_array", __func__);
  		return r;
  	}
  	if (fido_blob_serialise(&cbor, item) < 0) {
  		fido_log_debug("%s: fido_blob_serialise", __func__);
  		r = FIDO_ERR_INTERNAL;
  	} else {
  		*cbor_ptr = cbor.ptr;
  		*cbor_len = cbor.len;
  	}
  
  	cbor_decref(&item);
  
  	return r;
  }
  
  int
  fido_dev_largeblob_set_array(fido_dev_t *dev, const unsigned char *cbor_ptr,
      size_t cbor_len, const char *pin)
  {
  	cbor_item_t *item = NULL;
  	struct cbor_load_result cbor_result;
  	int r;
  
  	if (cbor_ptr == NULL || cbor_len == 0) {
  		fido_log_debug("%s: invalid cbor_ptr=%p, cbor_len=%zu", __func__,
  		    (const void *)cbor_ptr, cbor_len);
  		return FIDO_ERR_INVALID_ARGUMENT;
  	}
  	if ((item = cbor_load(cbor_ptr, cbor_len, &cbor_result)) == NULL) {
  		fido_log_debug("%s: cbor_load", __func__);
  		return FIDO_ERR_INVALID_ARGUMENT;
  	}
  	if ((r = largeblob_set_array(dev, item, pin)) != FIDO_OK)
  		fido_log_debug("%s: largeblob_set_array", __func__);
  
  	cbor_decref(&item);
  
  	return r;
  }
  