Files
pico-fido/src/fido/cbor_cred_mgmt.c
Pol Henarejos a59cdef8e6 Merge branch 'main' into development
Signed-off-by: Pol Henarejos <pol.henarejos@cttc.es>

# Conflicts:
#	pico-keys-sdk
2025-10-26 20:12:26 +01:00

473 lines
20 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 Affero 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
* Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include "pico_keys.h"
#include "fido.h"
#include "ctap.h"
#include "hid/ctap_hid.h"
#include "cbor_make_credential.h"
#include "files.h"
#include "apdu.h"
#include "credential.h"
uint8_t rp_counter = 1;
uint8_t rp_total = 0;
uint8_t cred_counter = 1;
uint8_t cred_total = 0;
CborByteString rpIdHashx = { 0 };
int cbor_cred_mgmt(const uint8_t *data, size_t len) {
CborParser parser;
CborValue map;
CborError error = CborNoError;
uint64_t subcommand = 0, pinUvAuthProtocol = 0;
CborByteString pinUvAuthParam = { 0 }, rpIdHash = { 0 };
PublicKeyCredentialDescriptor credentialId = { 0 };
PublicKeyCredentialUserEntity user = { 0 };
size_t resp_size = 0;
CborEncoder encoder, mapEncoder, mapEncoder2;
uint8_t *raw_subpara = NULL;
size_t raw_subpara_len = 0;
bool asserted = false, is_preview = *(data - 1) == 0x41; // Backwards compatibility
CBOR_CHECK(cbor_parser_init(data, len, 0, &parser, &map));
uint64_t val_c = 1;
CBOR_PARSE_MAP_START(map, 1)
{
uint64_t val_u = 0;
CBOR_FIELD_GET_UINT(val_u, 1);
if (val_c <= 1 && 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(subcommand, 1);
}
else if (val_u == 0x02) {
uint64_t subpara = 0;
raw_subpara = (uint8_t *) cbor_value_get_next_byte(&_f1);
CBOR_PARSE_MAP_START(_f1, 2)
{
CBOR_FIELD_GET_UINT(subpara, 2);
if (subpara == 0x01) {
CBOR_FIELD_GET_BYTES(rpIdHash, 2);
}
else if (subpara == 0x02) {
CBOR_PARSE_MAP_START(_f2, 3)
{
CBOR_FIELD_GET_KEY_TEXT(3);
CBOR_FIELD_KEY_TEXT_VAL_BYTES(3, "id", credentialId.id);
CBOR_FIELD_KEY_TEXT_VAL_TEXT(3, "type", credentialId.type);
if (strcmp(_fd3, "transports") == 0) {
CBOR_PARSE_ARRAY_START(_f3, 4)
{
CBOR_FIELD_GET_TEXT(credentialId.transports[credentialId.transports_len], 4);
credentialId.transports_len++;
}
CBOR_PARSE_ARRAY_END(_f3, 4);
}
}
CBOR_PARSE_MAP_END(_f2, 3);
}
else if (subpara == 0x03) {
CBOR_PARSE_MAP_START(_f1, 3)
{
CBOR_FIELD_GET_KEY_TEXT(3);
CBOR_FIELD_KEY_TEXT_VAL_BYTES(3, "id", user.id);
CBOR_FIELD_KEY_TEXT_VAL_TEXT(3, "name", user.parent.name);
CBOR_FIELD_KEY_TEXT_VAL_TEXT(3, "displayName", user.displayName);
}
CBOR_PARSE_MAP_END(_f1, 3);
}
}
CBOR_PARSE_MAP_END(_f1, 2);
raw_subpara_len = cbor_value_get_next_byte(&_f1) - raw_subpara;
}
else if (val_u == 0x03) {
CBOR_FIELD_GET_UINT(pinUvAuthProtocol, 1);
}
else if (val_u == 0x04) { // pubKeyCredParams
CBOR_FIELD_GET_BYTES(pinUvAuthParam, 1);
}
}
CBOR_PARSE_MAP_END(map, 1);
if (subcommand != 0x03 && subcommand != 0x05) {
if (pinUvAuthParam.present == false) {
CBOR_ERROR(CTAP2_ERR_PUAT_REQUIRED);
}
if (pinUvAuthProtocol != 1 && pinUvAuthProtocol != 2) {
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
}
}
cbor_encoder_init(&encoder, ctap_resp->init.data + 1, CTAP_MAX_CBOR_PAYLOAD, 0);
if (subcommand == 0x01) {
if (verify((uint8_t)pinUvAuthProtocol, ppaut.data, (const uint8_t *) "\x01", 1, pinUvAuthParam.data) == CborNoError) {
if (!(ppaut.permissions & CTAP_PERMISSION_PCMR)) {
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
}
else {
if (verify((uint8_t)pinUvAuthProtocol, paut.data, (const uint8_t *) "\x01", 1, pinUvAuthParam.data) != CborNoError) {
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
if (is_preview == false &&
(!(paut.permissions & CTAP_PERMISSION_CM) || paut.has_rp_id == true)) {
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
}
uint8_t existing = 0;
for (int i = 0; i < MAX_RESIDENT_CREDENTIALS; i++) {
if (file_has_data(search_dynamic_file((uint16_t)(EF_CRED + i)))) {
existing++;
}
}
CBOR_CHECK(cbor_encoder_create_map(&encoder, &mapEncoder, 2));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x01));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, existing));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x02));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, MAX_RESIDENT_CREDENTIALS - existing));
}
else if (subcommand == 0x02 || subcommand == 0x03) {
file_t *rp_ef = NULL;
if (subcommand == 0x02) {
if (verify((uint8_t)pinUvAuthProtocol, ppaut.data, (const uint8_t *) "\x02", 1, pinUvAuthParam.data) == CborNoError) {
if (!(ppaut.permissions & CTAP_PERMISSION_PCMR)) {
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
}
else {
if (verify((uint8_t)pinUvAuthProtocol, paut.data, (const uint8_t *) "\x02", 1, pinUvAuthParam.data) != CborNoError) {
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
if (is_preview == false && (!(paut.permissions & CTAP_PERMISSION_CM) || paut.has_rp_id == true)) {
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
}
rp_counter = 1;
rp_total = 0;
}
else {
if (rp_counter > rp_total) {
CBOR_ERROR(CTAP2_ERR_NOT_ALLOWED);
}
}
uint8_t skip = 0;
for (int i = 0; i < MAX_RESIDENT_CREDENTIALS; i++) {
file_t *tef = search_dynamic_file((uint16_t)(EF_RP + i));
if (file_has_data(tef) && *file_get_data(tef) > 0) {
if (++skip == rp_counter) {
if (rp_ef == NULL) {
rp_ef = tef;
}
if (subcommand == 0x03) {
break;
}
}
if (subcommand == 0x02) {
rp_total++;
}
}
}
if (rp_ef == NULL) {
CBOR_ERROR(CTAP2_ERR_NO_CREDENTIALS);
}
rp_counter++;
CBOR_CHECK(cbor_encoder_create_map(&encoder, &mapEncoder, subcommand == 0x02 ? 3 : 2));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x03));
CBOR_CHECK(cbor_encoder_create_map(&mapEncoder, &mapEncoder2, 1));
CBOR_CHECK(cbor_encode_text_stringz(&mapEncoder2, "id"));
CBOR_CHECK(cbor_encode_text_string(&mapEncoder2, (char *) file_get_data(rp_ef) + 33,
file_get_size(rp_ef) - 33));
CBOR_CHECK(cbor_encoder_close_container(&mapEncoder, &mapEncoder2));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x04));
CBOR_CHECK(cbor_encode_byte_string(&mapEncoder, file_get_data(rp_ef) + 1, 32));
if (subcommand == 0x02) {
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x05));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, rp_total));
}
}
else if (subcommand == 0x04 || subcommand == 0x05) {
if (subcommand == 0x04 && rpIdHash.present == false) {
CBOR_ERROR(CTAP2_ERR_MISSING_PARAMETER);
}
if (subcommand == 0x04) {
*(raw_subpara - 1) = 0x04;
if (verify((uint8_t)pinUvAuthProtocol, ppaut.data, raw_subpara - 1, (uint16_t)(raw_subpara_len + 1), pinUvAuthParam.data) == CborNoError) {
if (!(ppaut.permissions & CTAP_PERMISSION_PCMR)) {
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
}
else {
if (verify((uint8_t)pinUvAuthProtocol, paut.data, raw_subpara - 1, (uint16_t)(raw_subpara_len + 1), pinUvAuthParam.data) != CborNoError) {
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
if (is_preview == false &&
(!(paut.permissions & CTAP_PERMISSION_CM) ||
(paut.has_rp_id == true && memcmp(paut.rp_id_hash, rpIdHash.data, 32) != 0))) {
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
}
cred_counter = 1;
cred_total = 0;
}
else {
if (cred_counter > cred_total) {
CBOR_ERROR(CTAP2_ERR_NOT_ALLOWED);
}
rpIdHash = rpIdHashx;
}
file_t *cred_ef = NULL;
uint8_t skip = 0;
for (int i = 0; i < MAX_RESIDENT_CREDENTIALS; i++) {
file_t *tef = search_dynamic_file((uint16_t)(EF_CRED + i));
if (file_has_data(tef) && memcmp(file_get_data(tef), rpIdHash.data, 32) == 0) {
if (++skip == cred_counter) {
if (cred_ef == NULL) {
cred_ef = tef;
}
if (subcommand == 0x05) {
break;
}
}
if (subcommand == 0x04) {
cred_total++;
}
}
}
if (!file_has_data(cred_ef)) {
CBOR_ERROR(CTAP2_ERR_NO_CREDENTIALS);
}
Credential cred = { 0 };
if (credential_load_resident(cred_ef, rpIdHash.data, &cred) != 0) {
CBOR_ERROR(CTAP2_ERR_NOT_ALLOWED);
}
mbedtls_ecp_keypair key;
mbedtls_ecp_keypair_init(&key);
if (fido_load_key((int)cred.curve, cred.id.data, &key) != 0) {
credential_free(&cred);
mbedtls_ecp_keypair_free(&key);
CBOR_ERROR(CTAP2_ERR_NOT_ALLOWED);
}
cred_counter++;
uint8_t l = 4;
if (subcommand == 0x04) {
l++;
}
if (cred.extensions.present == true) {
if (cred.extensions.credProtect > 0) {
l++;
}
if (cred.extensions.largeBlobKey == ptrue) {
l++;
}
}
CBOR_CHECK(cbor_encoder_create_map(&encoder, &mapEncoder, l));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x06));
l = 0;
if (cred.userId.present == true) {
l++;
}
if (cred.userName.present == true) {
l++;
}
if (cred.userDisplayName.present == true) {
l++;
}
CBOR_CHECK(cbor_encoder_create_map(&mapEncoder, &mapEncoder2, l));
if (cred.userId.present == true) {
CBOR_CHECK(cbor_encode_text_stringz(&mapEncoder2, "id"));
CBOR_CHECK(cbor_encode_byte_string(&mapEncoder2, cred.userId.data, cred.userId.len));
}
if (cred.userName.present == true) {
CBOR_CHECK(cbor_encode_text_stringz(&mapEncoder2, "name"));
CBOR_CHECK(cbor_encode_text_string(&mapEncoder2, cred.userName.data, cred.userName.len));
}
if (cred.userDisplayName.present == true) {
CBOR_CHECK(cbor_encode_text_stringz(&mapEncoder2, "displayName"));
CBOR_CHECK(cbor_encode_text_string(&mapEncoder2, cred.userDisplayName.data, cred.userDisplayName.len));
}
CBOR_CHECK(cbor_encoder_close_container(&mapEncoder, &mapEncoder2));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x07));
CBOR_CHECK(cbor_encoder_create_map(&mapEncoder, &mapEncoder2, 2));
CBOR_CHECK(cbor_encode_text_stringz(&mapEncoder2, "id"));
uint8_t cred_idr[CRED_RESIDENT_LEN] = {0};
credential_derive_resident(cred.id.data, cred.id.len, cred_idr);
CBOR_CHECK(cbor_encode_byte_string(&mapEncoder2, cred_idr, sizeof(cred_idr)));
CBOR_CHECK(cbor_encode_text_stringz(&mapEncoder2, "type"));
CBOR_CHECK(cbor_encode_text_stringz(&mapEncoder2, "public-key"));
CBOR_CHECK(cbor_encoder_close_container(&mapEncoder, &mapEncoder2));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x08));
CBOR_CHECK(COSE_key(&key, &mapEncoder, &mapEncoder2));
if (subcommand == 0x04) {
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x09));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, cred_total));
}
if (cred_counter <= cred_total) {
asserted = true;
rpIdHashx = rpIdHash;
}
if (cred.extensions.present == true) {
if (cred.extensions.credProtect > 0) {
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x0A));
CBOR_CHECK(cbor_encode_uint(&mapEncoder, cred.extensions.credProtect));
}
if (cred.extensions.largeBlobKey == ptrue) {
uint8_t largeBlobKey[32];
int ret = credential_derive_large_blob_key(cred.id.data, cred.id.len, largeBlobKey);
if (ret != 0) {
CBOR_ERROR(CTAP2_ERR_PROCESSING);
}
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x0B));
CBOR_CHECK(cbor_encode_byte_string(&mapEncoder, largeBlobKey, sizeof(largeBlobKey)));
mbedtls_platform_zeroize(largeBlobKey, sizeof(largeBlobKey));
}
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x0C));
CBOR_CHECK(cbor_encode_boolean(&mapEncoder, cred.extensions.thirdPartyPayment == ptrue));
}
else {
CBOR_CHECK(cbor_encode_uint(&mapEncoder, 0x0C));
CBOR_CHECK(cbor_encode_boolean(&mapEncoder, false));
}
credential_free(&cred);
mbedtls_ecp_keypair_free(&key);
}
else if (subcommand == 0x06) {
if (credentialId.id.present == false) {
CBOR_ERROR(CTAP2_ERR_MISSING_PARAMETER);
}
*(raw_subpara - 1) = 0x06;
if (verify((uint8_t)pinUvAuthProtocol, paut.data, raw_subpara - 1, (uint16_t)(raw_subpara_len + 1), pinUvAuthParam.data) != CborNoError) {
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
if (is_preview == false &&
(!(paut.permissions & CTAP_PERMISSION_CM) ||
(paut.has_rp_id == true && memcmp(paut.rp_id_hash, rpIdHash.data, 32) != 0))) {
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
for (int i = 0; i < MAX_RESIDENT_CREDENTIALS; i++) {
file_t *ef = search_dynamic_file((uint16_t)(EF_CRED + i));
if (file_has_data(ef) && memcmp(file_get_data(ef) + 32, credentialId.id.data, CRED_RESIDENT_LEN) == 0) {
uint8_t *rp_id_hash = file_get_data(ef);
if (delete_file(ef) != 0) {
CBOR_ERROR(CTAP2_ERR_NOT_ALLOWED);
}
for (int j = 0; j < MAX_RESIDENT_CREDENTIALS; j++) {
file_t *rp_ef = search_dynamic_file((uint16_t)(EF_RP + j));
if (file_has_data(rp_ef) && memcmp(file_get_data(rp_ef) + 1, rp_id_hash, 32) == 0) {
uint8_t *rp_data = (uint8_t *) calloc(1, file_get_size(rp_ef));
memcpy(rp_data, file_get_data(rp_ef), file_get_size(rp_ef));
rp_data[0] -= 1;
if (rp_data[0] == 0) {
delete_file(rp_ef);
}
else {
file_put_data(rp_ef, rp_data, file_get_size(rp_ef));
}
free(rp_data);
break;
}
}
low_flash_available();
goto err; //no error
}
}
CBOR_ERROR(CTAP2_ERR_NO_CREDENTIALS);
}
else if (subcommand == 0x07) {
if (credentialId.id.present == false || user.id.present == false) {
CBOR_ERROR(CTAP2_ERR_MISSING_PARAMETER);
}
*(raw_subpara - 1) = 0x07;
if (verify((uint8_t)pinUvAuthProtocol, paut.data, raw_subpara - 1, (uint16_t)(raw_subpara_len + 1), pinUvAuthParam.data) != CborNoError) {
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
if (is_preview == false &&
(!(paut.permissions & CTAP_PERMISSION_CM) ||
(paut.has_rp_id == true && memcmp(paut.rp_id_hash, rpIdHash.data, 32) != 0))) {
CBOR_ERROR(CTAP2_ERR_PIN_AUTH_INVALID);
}
for (int i = 0; i < MAX_RESIDENT_CREDENTIALS; i++) {
file_t *ef = search_dynamic_file((uint16_t)(EF_CRED + i));
if (file_has_data(ef) && memcmp(file_get_data(ef) + 32, credentialId.id.data, CRED_RESIDENT_LEN) == 0) {
Credential cred = { 0 };
uint8_t *rp_id_hash = file_get_data(ef);
if (credential_load_resident(ef, rp_id_hash, &cred) != 0) {
CBOR_ERROR(CTAP2_ERR_NOT_ALLOWED);
}
if (memcmp(user.id.data, cred.userId.data, MIN(user.id.len, cred.userId.len)) != 0) {
credential_free(&cred);
CBOR_ERROR(CTAP1_ERR_INVALID_PARAMETER);
}
uint8_t newcred[MAX_CRED_ID_LENGTH];
uint16_t newcred_len = 0;
if (credential_create(&cred.rpId, &cred.userId, &user.parent.name,
&user.displayName, &cred.opts, &cred.extensions,
cred.use_sign_count, (int)cred.alg,
(int)cred.curve, newcred, &newcred_len) != 0) {
credential_free(&cred);
CBOR_ERROR(CTAP2_ERR_NOT_ALLOWED);
}
credential_free(&cred);
if (credential_store(newcred, newcred_len, rp_id_hash) != 0) {
CBOR_ERROR(CTAP2_ERR_NOT_ALLOWED);
}
low_flash_available();
goto err; //no error
}
}
CBOR_ERROR(CTAP2_ERR_NO_CREDENTIALS);
}
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);
if (asserted == false) {
CBOR_FREE_BYTE_STRING(rpIdHash);
}
CBOR_FREE_BYTE_STRING(user.id);
CBOR_FREE_BYTE_STRING(user.displayName);
CBOR_FREE_BYTE_STRING(user.parent.name);
CBOR_FREE_BYTE_STRING(credentialId.type);
CBOR_FREE_BYTE_STRING(credentialId.id);
for (size_t n = 0; n < credentialId.transports_len; n++) {
CBOR_FREE_BYTE_STRING(credentialId.transports[n]);
}
if (error != CborNoError) {
if (error == CborErrorImproperValue) {
return CTAP2_ERR_CBOR_UNEXPECTED_TYPE;
}
return error;
}
res_APDU_size = (uint16_t)resp_size;
return 0;
}