Files
pico-fido/src/fido/cbor_client_pin.c
Pol Henarejos 23c7e16e6e Fix counting PIN retries.
Signed-off-by: Pol Henarejos <pol.henarejos@cttc.es>
2022-11-23 16:42:49 +01:00

554 lines
21 KiB
C

/*
* This file is part of the Pico FIDO distribution (https://github.com/polhenarejos/pico-fido).
* Copyright (c) 2022 Pol Henarejos.
*
* 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, version 3.
*
* 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 <http://www.gnu.org/licenses/>.
*/
#include "common.h"
#include "mbedtls/ecp.h"
#include "mbedtls/ecdh.h"
#include "mbedtls/sha256.h"
#include "mbedtls/hkdf.h"
#include "cbor.h"
#include "ctap.h"
#include "ctap2_cbor.h"
#include "bsp/board.h"
#include "fido.h"
#include "files.h"
#include "random.h"
#include "crypto_utils.h"
#include "hsm.h"
#include "apdu.h"
uint8_t permissions_rp_id = 0, permission_set = 0;
uint32_t usage_timer = 0, initial_usage_time_limit = 0;
uint32_t max_usage_time_period = 600*1000;
bool needs_power_cycle = false;
static mbedtls_ecdh_context hkey;
static bool hkey_init = false;
int beginUsingPinUvAuthToken(bool userIsPresent) {
paut.user_present = userIsPresent;
paut.user_verified = true;
initial_usage_time_limit = board_millis();
usage_timer = board_millis();
paut.in_use = true;
return 0;
}
void clearUserPresentFlag() {
if (paut.in_use == true)
paut.user_present = false;
}
void clearUserVerifiedFlag() {
if (paut.in_use == true)
paut.user_verified = false;
}
void clearPinUvAuthTokenPermissionsExceptLbw() {
if (paut.in_use == true)
paut.permissions = FIDO2_PERMISSION_LBW;
}
void stopUsingPinUvAuthToken() {
permissions_rp_id = 0;
paut.permissions = 0;
usage_timer = 0;
paut.in_use = false;
memset(paut.rp_id_hash, 0, sizeof(paut.rp_id_hash));
initial_usage_time_limit = 0;
paut.user_present = paut.user_verified = false;
user_present_time_limit = 0;
}
bool getUserPresentFlagValue() {
if (paut.in_use != true)
paut.user_present = false;
return paut.user_present;
}
bool getUserVerifiedFlagValue() {
if (paut.in_use != true)
paut.user_verified = false;
return paut.user_verified;
}
int regenerate() {
if (hkey_init == true)
mbedtls_ecdh_free(&hkey);
mbedtls_ecdh_init(&hkey);
hkey_init = true;
mbedtls_ecdh_setup(&hkey, MBEDTLS_ECP_DP_SECP256R1);
int ret = mbedtls_ecdh_gen_public(&hkey.ctx.mbed_ecdh.grp, &hkey.ctx.mbed_ecdh.d, &hkey.ctx.mbed_ecdh.Q, random_gen, NULL);
mbedtls_mpi_lset(&hkey.ctx.mbed_ecdh.Qp.Z, 1);
if (ret != 0)
return ret;
return 0;
}
int kdf(uint8_t protocol, const mbedtls_mpi *z, uint8_t *sharedSecret) {
int ret = 0;
uint8_t buf[32];
ret = mbedtls_mpi_write_binary(z, buf, sizeof(buf));
if (ret != 0)
return ret;
if (protocol == 1) {
return mbedtls_md(mbedtls_md_info_from_type(MBEDTLS_MD_SHA256), buf, sizeof(buf), sharedSecret);
}
else if (protocol == 2) {
const mbedtls_md_info_t *md_info = mbedtls_md_info_from_type(MBEDTLS_MD_SHA256);
ret = mbedtls_hkdf(md_info, NULL, 0, buf, sizeof(buf), (uint8_t *)"CTAP2 HMAC key", 14, sharedSecret, 32);
if (ret != 0)
return ret;
return mbedtls_hkdf(md_info, NULL, 0, buf, sizeof(buf), (uint8_t *)"CTAP2 AES key", 13, sharedSecret+32, 32);
}
return -1;
}
int ecdh(uint8_t protocol, const mbedtls_ecp_point *Q, uint8_t *sharedSecret) {
mbedtls_mpi z;
mbedtls_mpi_init(&z);
int ret = mbedtls_ecdh_compute_shared(&hkey.ctx.mbed_ecdh.grp, &z, Q, &hkey.ctx.mbed_ecdh.d, random_gen, NULL);
ret = kdf(protocol, &z, sharedSecret);
mbedtls_mpi_free(&z);
return ret;
}
int resetPinUvAuthToken() {
uint8_t t[32];
random_gen(NULL, t, sizeof(t));
flash_write_data_to_file(ef_authtoken, t, sizeof(t));
paut.permissions = 0;
paut.data = file_get_data(ef_authtoken);
paut.len = file_get_size(ef_authtoken);
low_flash_available();
return 0;
}
int encrypt(uint8_t protocol, const uint8_t *key, const uint8_t *in, size_t in_len, uint8_t *out) {
if (protocol == 1) {
memcpy(out, in, in_len);
return aes_encrypt(key, NULL, 32*8, HSM_AES_MODE_CBC, out, in_len);
}
else if (protocol == 2) {
random_gen(NULL, out, IV_SIZE);
memcpy(out + IV_SIZE, in, in_len);
return aes_encrypt(key+32, out, 32*8, HSM_AES_MODE_CBC, out+IV_SIZE, in_len);
}
return -1;
}
int decrypt(uint8_t protocol, const uint8_t *key, const uint8_t *in, size_t in_len, uint8_t *out) {
if (protocol == 1) {
memcpy(out, in, in_len);
return aes_decrypt(key, NULL, 32*8, HSM_AES_MODE_CBC, out, in_len);
}
else if (protocol == 2) {
memcpy(out, in+IV_SIZE, in_len);
return aes_decrypt(key+32, in, 32*8, HSM_AES_MODE_CBC, out, in_len-IV_SIZE);
}
return -1;
}
int authenticate(uint8_t protocol, const uint8_t *key, const uint8_t *data, size_t len, uint8_t *sign) {
uint8_t hmac[32];
int ret = mbedtls_md_hmac(mbedtls_md_info_from_type(MBEDTLS_MD_SHA256), key, 32, data, len, hmac);
if (ret != 0)
return ret;
if (protocol == 1) {
memcpy(sign, hmac, 16);
}
else if (protocol == 2) {
memcpy(sign, hmac, 32);
}
else
return -1;
return 0;
}
int verify(uint8_t protocol, const uint8_t *key, const uint8_t *data, size_t len, uint8_t *sign) {
uint8_t hmac[32];
//if (paut.in_use == false)
// return -2;
int ret = mbedtls_md_hmac(mbedtls_md_info_from_type(MBEDTLS_MD_SHA256), key, 32, data, len, hmac);
if (ret != 0)
return ret;
if (protocol == 1)
return memcmp(sign, hmac, 16);
else if (protocol == 2)
return memcmp(sign, hmac, 32);
return -1;
}
int initialize() {
regenerate();
return resetPinUvAuthToken();
}
int getPublicKey() {
return 0;
}
int pinUvAuthTokenUsageTimerObserver() {
if (usage_timer == 0)
return -1;
if (usage_timer+max_usage_time_period > board_millis()) {
if (user_present_time_limit == 0 || user_present_time_limit+TRANSPORT_TIME_LIMIT < board_millis())
clearUserPresentFlag();
if (paut.in_use == true) {
if (initial_usage_time_limit == 0 || initial_usage_time_limit+TRANSPORT_TIME_LIMIT < board_millis()) {
stopUsingPinUvAuthToken();
return 1;
}
}
// TO DO: implement a rolling timer
}
return 0;
}
uint8_t new_pin_mismatches = 0;
int cbor_client_pin(const uint8_t *data, size_t len) {
size_t resp_size = 0;
uint64_t subcommand = 0x0, pinUvAuthProtocol = 0, permissions = 0;
int64_t kty = 0, alg = 0, crv = 0;
CborParser parser;
CborEncoder encoder, mapEncoder;
CborValue map;
CborError error = CborNoError;
CborByteString pinUvAuthParam = {0}, newPinEnc = {0}, pinHashEnc = {0}, kax = {0}, kay = {0};
CborCharString rpId = {0};
CBOR_CHECK(cbor_parser_init(data, len, 0, &parser, &map));
uint64_t val_c = 1;
if (hkey_init == false)
initialize();
CBOR_PARSE_MAP_START(map, 1)
{
uint64_t val_u = 0;
CBOR_FIELD_GET_UINT(val_u, 1);
if (val_c <= 2 && val_c != val_u)
CBOR_ERROR(CTAP2_ERR_MISSING_PARAMETER);
if (val_u < val_c)
CBOR_ERROR(CTAP2_ERR_INVALID_CBOR);
val_c = val_u + 1;
if (val_u == 0x01) {
CBOR_FIELD_GET_UINT(pinUvAuthProtocol, 1);
}
else if (val_u == 0x02) {
CBOR_FIELD_GET_UINT(subcommand, 1);
}
else if (val_u == 0x03) {
int64_t key = 0;
CBOR_PARSE_MAP_START(_f1, 2) {
CBOR_FIELD_GET_INT(key, 2);
if (key == 1) {
CBOR_FIELD_GET_INT(kty, 2);
}
else if (key == 3) {
CBOR_FIELD_GET_INT(alg, 2);
}
else if (key == -1) {
CBOR_FIELD_GET_INT(crv, 2);
}
else if (key == -2) {
CBOR_FIELD_GET_BYTES(kax, 2);
}
else if (key == -3) {
CBOR_FIELD_GET_BYTES(kay, 2);
}
else
CBOR_ADVANCE(2);
}
CBOR_PARSE_MAP_END(_f1, 2);
}
else if (val_u == 0x04) {
CBOR_FIELD_GET_BYTES(pinUvAuthParam, 1);
}
else if (val_u == 0x05) {
CBOR_FIELD_GET_BYTES(newPinEnc, 1);
}
else if (val_u == 0x06) {
CBOR_FIELD_GET_BYTES(pinHashEnc, 1);
}
else if (val_u == 0x09) {
CBOR_FIELD_GET_UINT(permissions, 1);
}
else if (val_u == 0x0A) {
CBOR_FIELD_GET_TEXT(rpId, 1);
}
}
CBOR_PARSE_MAP_END(map, 1);
cbor_encoder_init(&encoder, ctap_resp->init.data + 1, CTAP_MAX_PACKET_SIZE, 0);
if (subcommand == 0x0)
CBOR_ERROR(CTAP2_ERR_MISSING_PARAMETER);
else if (subcommand == 0x1) { //getPINRetries
CBOR_CHECK(cbor_encoder_create_map(&encoder, &mapEncoder, needs_power_cycle ? 2 : 1));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x03));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, (uint64_t)*file_get_data(ef_pin)));
if (needs_power_cycle) {
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x04));
CBOR_CHECK(cbor_encode_boolean(&mapEncoder, true));
}
}
else if (subcommand == 0x2) { //getKeyAgreement
if (pinUvAuthProtocol == 1 || pinUvAuthProtocol == 2) {
CborEncoder mapEncoder2;
CBOR_CHECK(cbor_encoder_create_map(&encoder, &mapEncoder, 1));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x01));
CBOR_CHECK(cbor_encoder_create_map(&mapEncoder, &mapEncoder2, 5));
CBOR_CHECK(cbor_encode_uint(&mapEncoder2, 1));
CBOR_CHECK(cbor_encode_uint(&mapEncoder2, 2));
CBOR_CHECK(cbor_encode_uint(&mapEncoder2, 3));
CBOR_CHECK(cbor_encode_negative_int(&mapEncoder2, -FIDO2_ALG_ECDH_ES_HKDF_256));
CBOR_CHECK(cbor_encode_negative_int(&mapEncoder2, 1));
CBOR_CHECK(cbor_encode_uint(&mapEncoder2, FIDO2_CURVE_P256));
CBOR_CHECK(cbor_encode_negative_int(&mapEncoder2, 2));
uint8_t pkey[32];
mbedtls_mpi_write_binary(&hkey.ctx.mbed_ecdh.Q.X, pkey, 32);
CBOR_CHECK(cbor_encode_byte_string(&mapEncoder2, pkey, 32));
CBOR_CHECK(cbor_encode_negative_int(&mapEncoder2, 3));
mbedtls_mpi_write_binary(&hkey.ctx.mbed_ecdh.Q.Y, pkey, 32);
CBOR_CHECK(cbor_encode_byte_string(&mapEncoder2, pkey, 32));
CBOR_CHECK(cbor_encoder_close_container(&mapEncoder, &mapEncoder2));
}
else if (pinUvAuthProtocol == 0)
CBOR_ERROR(CTAP2_ERR_MISSING_PARAMETER);
else
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
}
else if (subcommand == 0x3) { //setPIN
if (kax.present == false || kay.present == false || pinUvAuthProtocol == 0 || newPinEnc.present == false || pinUvAuthParam.present == false || alg == 0)
CBOR_ERROR(CTAP2_ERR_MISSING_PARAMETER);
if (pinUvAuthProtocol != 1 && pinUvAuthProtocol != 2)
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
if (file_has_data(ef_pin))
CBOR_ERROR(CTAP2_ERR_NOT_ALLOWED);
if ((pinUvAuthProtocol == 1 && newPinEnc.len != 64) || (pinUvAuthProtocol == 2 && newPinEnc.len != 64+IV_SIZE))
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
if (mbedtls_mpi_read_binary(&hkey.ctx.mbed_ecdh.Qp.X, kax.data, kax.len) != 0) {
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
}
if (mbedtls_mpi_read_binary(&hkey.ctx.mbed_ecdh.Qp.Y, kay.data, kay.len) != 0) {
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
}
uint8_t sharedSecret[64];
int ret = ecdh(pinUvAuthProtocol, &hkey.ctx.mbed_ecdh.Qp, sharedSecret);
if (ret != 0) {
mbedtls_platform_zeroize(sharedSecret, sizeof(sharedSecret));
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
}
if (verify(pinUvAuthProtocol, sharedSecret, newPinEnc.data, newPinEnc.len, pinUvAuthParam.data) != 0) {
mbedtls_platform_zeroize(sharedSecret, sizeof(sharedSecret));
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
uint8_t paddedNewPin[64];
ret = decrypt(pinUvAuthProtocol, sharedSecret, newPinEnc.data, newPinEnc.len, paddedNewPin);
mbedtls_platform_zeroize(sharedSecret, sizeof(sharedSecret));
if (ret != 0)
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
if (paddedNewPin[63] != 0)
CBOR_ERROR(CTAP2_ERR_PIN_POLICY_VIOLATION);
uint8_t pin_len = 0;
while (paddedNewPin[pin_len] != 0 && pin_len < sizeof(paddedNewPin))
pin_len++;
if (pin_len < 4)
CBOR_ERROR(CTAP2_ERR_PIN_POLICY_VIOLATION);
uint8_t hsh[34];
hsh[0] = MAX_PIN_RETRIES;
hsh[1] = pin_len;
mbedtls_md(mbedtls_md_info_from_type(MBEDTLS_MD_SHA256), paddedNewPin, pin_len, hsh + 2);
flash_write_data_to_file(ef_pin, hsh, 2+16);
low_flash_available();
goto err; //No return
}
else if (subcommand == 0x4) { //changePIN
if (kax.present == false || kay.present == false || pinUvAuthProtocol == 0 || newPinEnc.present == false || pinUvAuthParam.present == false || alg == 0 || pinHashEnc.present == false)
CBOR_ERROR(CTAP2_ERR_MISSING_PARAMETER);
if (pinUvAuthProtocol != 1 && pinUvAuthProtocol != 2)
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
if (!file_has_data(ef_pin))
CBOR_ERROR(CTAP2_ERR_PIN_NOT_SET);
if (*file_get_data(ef_pin) == 0)
CBOR_ERROR(CTAP2_ERR_PIN_BLOCKED);
if ((pinUvAuthProtocol == 1 && (newPinEnc.len != 64 || pinHashEnc.len != 16)) || (pinUvAuthProtocol == 2 && (newPinEnc.len != 64+IV_SIZE || pinHashEnc.len != 16+IV_SIZE)))
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
if (mbedtls_mpi_read_binary(&hkey.ctx.mbed_ecdh.Qp.X, kax.data, kax.len) != 0) {
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
}
if (mbedtls_mpi_read_binary(&hkey.ctx.mbed_ecdh.Qp.Y, kay.data, kay.len) != 0) {
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
}
uint8_t sharedSecret[64];
int ret = ecdh(pinUvAuthProtocol, &hkey.ctx.mbed_ecdh.Qp, sharedSecret);
if (ret != 0) {
mbedtls_platform_zeroize(sharedSecret, sizeof(sharedSecret));
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
}
uint8_t tmp[80 + 32];
memcpy(tmp, newPinEnc.data, newPinEnc.len);
memcpy(tmp + newPinEnc.len, pinHashEnc.data, pinHashEnc.len);
if (verify(pinUvAuthProtocol, sharedSecret, tmp, newPinEnc.len+pinHashEnc.len, pinUvAuthParam.data) != 0) {
mbedtls_platform_zeroize(sharedSecret, sizeof(sharedSecret));
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
uint8_t pin_data[18];
memcpy(pin_data, file_get_data(ef_pin), 18);
pin_data[0] -= 1;
flash_write_data_to_file(ef_pin, pin_data, sizeof(pin_data));
low_flash_available();
uint8_t retries = pin_data[0];
uint8_t paddedNewPin[64];
ret = decrypt(pinUvAuthProtocol, sharedSecret, pinHashEnc.data, pinHashEnc.len, paddedNewPin);
if (ret != 0) {
mbedtls_platform_zeroize(sharedSecret, sizeof(sharedSecret));
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
if (memcmp(paddedNewPin, file_get_data(ef_pin)+2, 16) != 0) {
regenerate();
mbedtls_platform_zeroize(sharedSecret, sizeof(sharedSecret));
if (retries == 0) {
CBOR_ERROR(CTAP2_ERR_PIN_BLOCKED);
}
if (++new_pin_mismatches >= 3) {
needs_power_cycle = true;
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_BLOCKED);
}
else
CBOR_ERROR(CTAP2_ERR_PIN_INVALID);
}
pin_data[0] = MAX_PIN_RETRIES;
flash_write_data_to_file(ef_pin, pin_data, sizeof(pin_data));
low_flash_available();
new_pin_mismatches = 0;
ret = decrypt(pinUvAuthProtocol, sharedSecret, newPinEnc.data, newPinEnc.len, paddedNewPin);
mbedtls_platform_zeroize(sharedSecret, sizeof(sharedSecret));
if (ret != 0) {
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
if (paddedNewPin[63] != 0)
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
uint8_t pin_len = 0;
while (paddedNewPin[pin_len] != 0 && pin_len < sizeof(paddedNewPin))
pin_len++;
if (pin_len < 4)
CBOR_ERROR(CTAP2_ERR_PIN_POLICY_VIOLATION);
uint8_t hsh[33];
hsh[0] = MAX_PIN_RETRIES;
hsh[1] = pin_len;
mbedtls_md(mbedtls_md_info_from_type(MBEDTLS_MD_SHA256), paddedNewPin, pin_len, hsh + 2);
flash_write_data_to_file(ef_pin, hsh, 2+16);
low_flash_available();
resetPinUvAuthToken();
goto err; // No return
}
else if (subcommand == 0x9 || subcommand == 0x5) { //getPinUvAuthTokenUsingPinWithPermissions
if (kax.present == false || kay.present == false || pinUvAuthProtocol == 0 || alg == 0 || pinHashEnc.present == false)
CBOR_ERROR(CTAP2_ERR_MISSING_PARAMETER);
if (pinUvAuthProtocol != 1 && pinUvAuthProtocol != 2)
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
if (subcommand == 0x5 && (permissions != 0 || rpId.present == true))
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
if (subcommand == 0x9) {
if (permissions == 0)
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
if ((permissions & CTAP_PERMISSION_BE) || (permissions & CTAP_PERMISSION_LBW)) // Not supported yet
CBOR_ERROR(CTAP2_ERR_UNAUTHORIZED_PERMISSION);
}
if (!file_has_data(ef_pin))
CBOR_ERROR(CTAP2_ERR_PIN_NOT_SET);
if (*file_get_data(ef_pin) == 0)
CBOR_ERROR(CTAP2_ERR_PIN_BLOCKED);
if (mbedtls_mpi_read_binary(&hkey.ctx.mbed_ecdh.Qp.X, kax.data, kax.len) != 0) {
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
}
if (mbedtls_mpi_read_binary(&hkey.ctx.mbed_ecdh.Qp.Y, kay.data, kay.len) != 0) {
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
}
uint8_t sharedSecret[64];
int ret = ecdh(pinUvAuthProtocol, &hkey.ctx.mbed_ecdh.Qp, sharedSecret);
if (ret != 0) {
mbedtls_platform_zeroize(sharedSecret, sizeof(sharedSecret));
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
}
uint8_t pin_data[18];
memcpy(pin_data, file_get_data(ef_pin), 18);
pin_data[0] -= 1;
flash_write_data_to_file(ef_pin, pin_data, sizeof(pin_data));
low_flash_available();
uint8_t retries = pin_data[0];
uint8_t paddedNewPin[64], poff = (pinUvAuthProtocol-1)*IV_SIZE;
ret = decrypt(pinUvAuthProtocol, sharedSecret, pinHashEnc.data, pinHashEnc.len, paddedNewPin);
if (ret != 0) {
mbedtls_platform_zeroize(sharedSecret, sizeof(sharedSecret));
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
if (memcmp(paddedNewPin, file_get_data(ef_pin)+1, 16) != 0) {
regenerate();
mbedtls_platform_zeroize(sharedSecret, sizeof(sharedSecret));
if (retries == 0) {
CBOR_ERROR(CTAP2_ERR_PIN_BLOCKED);
}
if (++new_pin_mismatches >= 3) {
needs_power_cycle = true;
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_BLOCKED);
}
else
CBOR_ERROR(CTAP2_ERR_PIN_INVALID);
}
pin_data[0] = MAX_PIN_RETRIES;
new_pin_mismatches = 0;
flash_write_data_to_file(ef_pin, pin_data, sizeof(pin_data));
low_flash_available();
beginUsingPinUvAuthToken(false);
if (subcommand == 0x05)
permissions = CTAP_PERMISSION_MC | CTAP_PERMISSION_GA;
paut.permissions = permissions;
if (rpId.present == true) {
memcpy(paut.rp_id_hash, rpId.data, 32);
paut.has_rp_id = true;
}
uint8_t pinUvAuthToken_enc[32+IV_SIZE];
encrypt(pinUvAuthProtocol, sharedSecret, paut.data, 32, pinUvAuthToken_enc);
CBOR_CHECK(cbor_encoder_create_map(&encoder, &mapEncoder, 1));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x02));
CBOR_CHECK(cbor_encode_byte_string(&mapEncoder, pinUvAuthToken_enc, 32+poff));
}
else
CBOR_ERROR(CTAP2_ERR_UNSUPPORTED_OPTION);
CBOR_CHECK(cbor_encoder_close_container(&encoder, &mapEncoder));
resp_size = cbor_encoder_get_buffer_size(&encoder, ctap_resp->init.data + 1);
err:
CBOR_FREE_BYTE_STRING(pinUvAuthParam);
CBOR_FREE_BYTE_STRING(newPinEnc);
CBOR_FREE_BYTE_STRING(pinHashEnc);
CBOR_FREE_BYTE_STRING(kax);
CBOR_FREE_BYTE_STRING(kay);
CBOR_FREE_BYTE_STRING(rpId);
if (error != CborNoError) {
if (error == CborErrorImproperValue)
return CTAP2_ERR_CBOR_UNEXPECTED_TYPE;
return error;
}
res_APDU_size = resp_size;
return 0;
}