dearsky/pico-hsm
1
0
Fork 0
Code Issues 17 Pull Requests 4 Actions Packages Projects Releases 26 Wiki Activity

Splitting cmd_xxx() functions in separate files.

Browse Source 
Signed-off-by: Pol Henarejos <pol.henarejos@cttc.es>
This commit is contained in:
Pol Henarejos
2022-08-13 14:59:27 +02:00
parent 87feed1222
commit e6f082d512
30 changed files with 2703 additions and 2004 deletions
Download Patch File Download Diff File Expand all files Collapse all files

170
src/hsm/cmd_decrypt_asym.c Normal file
View File

@@ -0,0 +1,170 @@
/*
* This file is part of the Pico HSM distribution (https://github.com/polhenarejos/pico-hsm).
* 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/ecdh.h"
#include "crypto_utils.h"
#include "sc_hsm.h"
#include "kek.h"
#include "files.h"
#include "asn1.h"
#include "cvc.h"
#include "random.h"
#include "oid.h"
int cmd_decrypt_asym() {
int key_id = P1(apdu);
uint8_t p2 = P2(apdu);
if (!isUserAuthenticated)
return SW_SECURITY_STATUS_NOT_SATISFIED();
file_t *ef = search_dynamic_file((KEY_PREFIX << 8) | key_id);
if (!ef)
return SW_FILE_NOT_FOUND();
if (get_key_counter(ef) == 0)
return SW_FILE_FULL();
if (key_has_purpose(ef, p2) == false)
return SW_CONDITIONS_NOT_SATISFIED();
if (p2 >= ALGO_RSA_DECRYPT && p2 <= ALGO_RSA_DECRYPT_OEP) {
mbedtls_rsa_context ctx;
mbedtls_rsa_init(&ctx);
if (p2 == ALGO_RSA_DECRYPT_OEP)
mbedtls_rsa_set_padding(&ctx, MBEDTLS_RSA_PKCS_V21, MBEDTLS_MD_NONE);
int r = load_private_key_rsa(&ctx, ef);
if (r != CCID_OK) {
mbedtls_rsa_free(&ctx);
if (r == CCID_VERIFICATION_FAILED)
return SW_SECURE_MESSAGE_EXEC_ERROR();
return SW_EXEC_ERROR();
}
int key_size = file_get_size(ef);
if (apdu.nc < key_size) //needs padding
memset(apdu.data+apdu.nc, 0, key_size-apdu.nc);
if (p2 == ALGO_RSA_DECRYPT_PKCS1 || p2 == ALGO_RSA_DECRYPT_OEP) {
size_t olen = apdu.nc;
r = mbedtls_rsa_pkcs1_decrypt(&ctx, random_gen, NULL, &olen, apdu.data, res_APDU, 512);
if (r == 0)
res_APDU_size = olen;
}
else {
r = mbedtls_rsa_private(&ctx, random_gen, NULL, apdu.data, res_APDU);
if (r == 0)
res_APDU_size = key_size;
}
if (r != 0) {
mbedtls_rsa_free(&ctx);
return SW_EXEC_ERROR();
}
mbedtls_rsa_free(&ctx);
}
else if (p2 == ALGO_EC_DH || p2 == ALGO_EC_DH_XKEK) {
mbedtls_ecdh_context ctx;
if (wait_button() == true) //timeout
return SW_SECURE_MESSAGE_EXEC_ERROR();
int key_size = file_get_size(ef);
uint8_t *kdata = (uint8_t *)calloc(1,key_size);
memcpy(kdata, file_get_data(ef), key_size);
if (mkek_decrypt(kdata, key_size) != 0) {
mbedtls_platform_zeroize(kdata, key_size);
free(kdata);
return SW_EXEC_ERROR();
}
mbedtls_ecdh_init(&ctx);
mbedtls_ecp_group_id gid = kdata[0];
int r = 0;
r = mbedtls_ecdh_setup(&ctx, gid);
if (r != 0) {
mbedtls_platform_zeroize(kdata, key_size);
mbedtls_ecdh_free(&ctx);
free(kdata);
return SW_DATA_INVALID();
}
r = mbedtls_mpi_read_binary(&ctx.ctx.mbed_ecdh.d, kdata+1, key_size-1);
mbedtls_platform_zeroize(kdata, key_size);
free(kdata);
if (r != 0) {
mbedtls_ecdh_free(&ctx);
return SW_DATA_INVALID();
}
r = -1;
if (p2 == ALGO_EC_DH)
r = mbedtls_ecdh_read_public(&ctx, apdu.data-1, apdu.nc+1);
else if (p2 == ALGO_EC_DH_XKEK) {
size_t pub_len = 0;
const uint8_t *pub = cvc_get_pub(apdu.data, apdu.nc, &pub_len);
if (pub) {
size_t t86_len = 0;
const uint8_t *t86 = cvc_get_field(pub, pub_len, &t86_len, 0x86);
if (t86) {
r = mbedtls_ecdh_read_public(&ctx, t86-1, t86_len+1);
}
}
}
if (r != 0) {
mbedtls_ecdh_free(&ctx);
return SW_DATA_INVALID();
}
size_t olen = 0;
res_APDU[0] = 0x04;
r = mbedtls_ecdh_calc_secret(&ctx, &olen, res_APDU+1, MBEDTLS_ECP_MAX_BYTES, random_gen, NULL);
if (r != 0) {
mbedtls_ecdh_free(&ctx);
return SW_EXEC_ERROR();
}
if (p2 == ALGO_EC_DH)
res_APDU_size = olen+1;
else {
res_APDU_size = 0;
size_t ext_len = 0;
const uint8_t *ext = NULL;
if ((ext = cvc_get_ext(apdu.data, apdu.nc, &ext_len)) == NULL)
return SW_WRONG_DATA();
uint8_t *p = NULL, *tag_data = NULL, *kdom_uid = NULL;
uint16_t tag = 0;
size_t tag_len = 0, kdom_uid_len = 0;
while (walk_tlv(ext, ext_len, &p, &tag, &tag_len, &tag_data)) {
if (tag == 0x73) {
size_t oid_len = 0;
uint8_t *oid_data = NULL;
if (asn1_find_tag(tag_data, tag_len, 0x6, &oid_len, &oid_data) == true && oid_len == strlen(OID_ID_KEY_DOMAIN_UID) && memcmp(oid_data, OID_ID_KEY_DOMAIN_UID, strlen(OID_ID_KEY_DOMAIN_UID)) == 0) {
if (asn1_find_tag(tag_data, tag_len, 0x80, &kdom_uid_len, &kdom_uid) == false)
return SW_WRONG_DATA();
break;
}
}
}
if (kdom_uid_len == 0 || kdom_uid == NULL)
return SW_WRONG_DATA();
for (int n = 0; n < MAX_KEY_DOMAINS; n++) {
file_t *tf = search_dynamic_file(EF_XKEK+n);
if (tf) {
if (file_get_size(tf) == kdom_uid_len && memcmp(file_get_data(tf), kdom_uid, kdom_uid_len) == 0) {
file_new(EF_DKEK+n);
if (store_dkek_key(n, res_APDU+1) != CCID_OK)
return SW_EXEC_ERROR();
return SW_OK();
}
}
}
return SW_REFERENCE_NOT_FOUND();
}
mbedtls_ecdh_free(&ctx);
}
else
return SW_WRONG_P1P2();
decrement_key_counter(ef);
return SW_OK();
}