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/*
* Copyright (c) 2020-2021 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 <assert.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "../openbsd-compat/openbsd-compat.h"
#include "mutator_aux.h"
#include "dummy.h"
extern int fido_hid_get_usage(const uint8_t *, size_t, uint32_t *);
extern int fido_hid_get_report_len(const uint8_t *, size_t, size_t *, size_t *);
extern void set_udev_parameters(const char *, const struct blob *);
struct param {
int seed;
char uevent[MAXSTR];
struct blob report_descriptor;
struct blob netlink_wiredata;
};
/*
* Sample HID report descriptor from the FIDO HID interface of a YubiKey 5.
*/
static const uint8_t dummy_report_descriptor[] = {
0x06, 0xd0, 0xf1, 0x09, 0x01, 0xa1, 0x01, 0x09,
0x20, 0x15, 0x00, 0x26, 0xff, 0x00, 0x75, 0x08,
0x95, 0x40, 0x81, 0x02, 0x09, 0x21, 0x15, 0x00,
0x26, 0xff, 0x00, 0x75, 0x08, 0x95, 0x40, 0x91,
0x02, 0xc0
};
/*
* Sample uevent file from a Yubico Security Key.
*/
static const char dummy_uevent[] =
"DRIVER=hid-generic\n"
"HID_ID=0003:00001050:00000120\n"
"HID_NAME=Yubico Security Key by Yubico\n"
"HID_PHYS=usb-0000:00:14.0-3/input0\n"
"HID_UNIQ=\n"
"MODALIAS=hid:b0003g0001v00001050p00000120\n";
struct param *
unpack(const uint8_t *ptr, size_t len)
{
cbor_item_t *item = NULL, **v;
struct cbor_load_result cbor;
struct param *p;
int ok = -1;
if ((p = calloc(1, sizeof(*p))) == NULL ||
(item = cbor_load(ptr, len, &cbor)) == NULL ||
cbor.read != len ||
cbor_isa_array(item) == false ||
cbor_array_is_definite(item) == false ||
cbor_array_size(item) != 4 ||
(v = cbor_array_handle(item)) == NULL)
goto fail;
if (unpack_int(v[0], &p->seed) < 0 ||
unpack_string(v[1], p->uevent) < 0 ||
unpack_blob(v[2], &p->report_descriptor) < 0 ||
unpack_blob(v[3], &p->netlink_wiredata) < 0)
goto fail;
ok = 0;
fail:
if (ok < 0) {
free(p);
p = NULL;
}
if (item)
cbor_decref(&item);
return p;
}
size_t
pack(uint8_t *ptr, size_t len, const struct param *p)
{
cbor_item_t *argv[4], *array = NULL;
size_t cbor_alloc_len, cbor_len = 0;
unsigned char *cbor = NULL;
memset(argv, 0, sizeof(argv));
if ((array = cbor_new_definite_array(4)) == NULL ||
(argv[0] = pack_int(p->seed)) == NULL ||
(argv[1] = pack_string(p->uevent)) == NULL ||
(argv[2] = pack_blob(&p->report_descriptor)) == NULL ||
(argv[3] = pack_blob(&p->netlink_wiredata)) == NULL)
goto fail;
for (size_t i = 0; i < 4; i++)
if (cbor_array_push(array, argv[i]) == false)
goto fail;
if ((cbor_len = cbor_serialize_alloc(array, &cbor,
&cbor_alloc_len)) == 0 || cbor_len > len) {
cbor_len = 0;
goto fail;
}
memcpy(ptr, cbor, cbor_len);
fail:
for (size_t i = 0; i < 4; i++)
if (argv[i])
cbor_decref(&argv[i]);
if (array)
cbor_decref(&array);
free(cbor);
return cbor_len;
}
size_t
pack_dummy(uint8_t *ptr, size_t len)
{
struct param dummy;
uint8_t blob[MAXCORPUS];
size_t blob_len;
memset(&dummy, 0, sizeof(dummy));
dummy.report_descriptor.len = sizeof(dummy_report_descriptor);
strlcpy(dummy.uevent, dummy_uevent, sizeof(dummy.uevent));
memcpy(&dummy.report_descriptor.body, &dummy_report_descriptor,
dummy.report_descriptor.len);
dummy.netlink_wiredata.len = sizeof(dummy_netlink_wiredata);
memcpy(&dummy.netlink_wiredata.body, &dummy_netlink_wiredata,
dummy.netlink_wiredata.len);
assert((blob_len = pack(blob, sizeof(blob), &dummy)) != 0);
if (blob_len > len)
blob_len = len;
memcpy(ptr, blob, blob_len);
return blob_len;
}
static void
get_usage(const struct param *p)
{
uint32_t usage_page = 0;
fido_hid_get_usage(p->report_descriptor.body, p->report_descriptor.len,
&usage_page);
consume(&usage_page, sizeof(usage_page));
}
static void
get_report_len(const struct param *p)
{
size_t report_in_len = 0;
size_t report_out_len = 0;
fido_hid_get_report_len(p->report_descriptor.body,
p->report_descriptor.len, &report_in_len, &report_out_len);
consume(&report_in_len, sizeof(report_in_len));
consume(&report_out_len, sizeof(report_out_len));
}
static void
manifest(const struct param *p)
{
size_t ndevs, nfound;
fido_dev_info_t *devlist = NULL, *devlist_set = NULL;
int16_t vendor_id, product_id;
fido_dev_io_t io;
fido_dev_transport_t t;
memset(&io, 0, sizeof(io));
memset(&t, 0, sizeof(t));
set_netlink_io_functions(fd_read, fd_write);
set_wire_data(p->netlink_wiredata.body, p->netlink_wiredata.len);
set_udev_parameters(p->uevent, &p->report_descriptor);
ndevs = uniform_random(64);
if ((devlist = fido_dev_info_new(ndevs)) == NULL ||
(devlist_set = fido_dev_info_new(1)) == NULL ||
fido_dev_info_manifest(devlist, ndevs, &nfound) != FIDO_OK)
goto out;
for (size_t i = 0; i < nfound; i++) {
const fido_dev_info_t *di = fido_dev_info_ptr(devlist, i);
consume_str(fido_dev_info_path(di));
consume_str(fido_dev_info_manufacturer_string(di));
consume_str(fido_dev_info_product_string(di));
vendor_id = fido_dev_info_vendor(di);
product_id = fido_dev_info_product(di);
consume(&vendor_id, sizeof(vendor_id));
consume(&product_id, sizeof(product_id));
fido_dev_info_set(devlist_set, 0, fido_dev_info_path(di),
fido_dev_info_manufacturer_string(di),
fido_dev_info_product_string(di), &io, &t);
}
out:
fido_dev_info_free(&devlist, ndevs);
fido_dev_info_free(&devlist_set, 1);
}
void
test(const struct param *p)
{
prng_init((unsigned int)p->seed);
fuzz_clock_reset();
fido_init(FIDO_DEBUG);
fido_set_log_handler(consume_str);
get_usage(p);
get_report_len(p);
manifest(p);
}
void
mutate(struct param *p, unsigned int seed, unsigned int flags) NO_MSAN
{
if (flags & MUTATE_SEED)
p->seed = (int)seed;
if (flags & MUTATE_PARAM) {
mutate_blob(&p->report_descriptor);
mutate_string(p->uevent);
}
if (flags & MUTATE_WIREDATA)
mutate_blob(&p->netlink_wiredata);
}
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