coelner/pico-hsm
1
0
Fork 0
mirror of https://github.com/polhenarejos/pico-hsm.git synced 2024-09-20 11:20:08 +00:00
Code Issues Packages Projects Releases Wiki Activity

Added ECDH key derivation.

Browse Source 
Signed-off-by: Pol Henarejos <pol.henarejos@cttc.es>
This commit is contained in:
Pol Henarejos 2022-03-17 00:28:16 +01:00
parent 23f53a6095
commit ab1490a50b
No known key found for this signature in database
GPG Key ID: C0095B7870A4CCD3
1 changed files with 61 additions and 15 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

76
src/hsm/sc_hsm.c
View File

@ -8,6 +8,7 @@
#include "mbedtls/rsa.h"
#include "mbedtls/ecp.h"
#include "mbedtls/ecdsa.h"
#include "mbedtls/ecdh.h"
#include "version.h"
const uint8_t sc_hsm_aid[] = {
@ -1477,28 +1478,73 @@ static int cmd_key_unwrap() {
static int cmd_decrypt_asym() {
int key_id = P1(apdu);
if (P2(apdu) != ALGO_RSA_DECRYPT)
return SW_WRONG_P1P2();
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();
mbedtls_rsa_context ctx;
mbedtls_rsa_init(&ctx);
int r = load_private_key_rsa(&ctx, ef);
if (r != HSM_OK)
return r;
int key_size = file_read_uint16(ef->data);
if (apdu.cmd_apdu_data_len < key_size) //needs padding
memset(apdu.cmd_apdu_data+apdu.cmd_apdu_data_len, 0, key_size-apdu.cmd_apdu_data_len);
r = mbedtls_rsa_private(&ctx, random_gen, NULL, apdu.cmd_apdu_data, res_APDU);
if (r != 0) {
if (P2(apdu) == ALGO_RSA_DECRYPT) {
mbedtls_rsa_context ctx;
mbedtls_rsa_init(&ctx);
int r = load_private_key_rsa(&ctx, ef);
if (r != HSM_OK)
return r;
int key_size = file_read_uint16(ef->data);
if (apdu.cmd_apdu_data_len < key_size) //needs padding
memset(apdu.cmd_apdu_data+apdu.cmd_apdu_data_len, 0, key_size-apdu.cmd_apdu_data_len);
r = mbedtls_rsa_private(&ctx, random_gen, NULL, apdu.cmd_apdu_data, res_APDU);
if (r != 0) {
mbedtls_rsa_free(&ctx);
return SW_EXEC_ERROR();
}
res_APDU_size = key_size;
mbedtls_rsa_free(&ctx);
return SW_EXEC_ERROR();
}
res_APDU_size = key_size;
mbedtls_rsa_free(&ctx);
else if (P2(apdu) == ALGO_EC_DH) {
mbedtls_ecdh_context ctx;
int key_size = file_read_uint16(ef->data);
if (load_dkek() != HSM_OK)
return SW_EXEC_ERROR();
uint8_t *kdata = (uint8_t *)calloc(1,key_size);
memcpy(kdata, file_read(ef->data+2), key_size);
if (decrypt(tmp_dkek+IV_SIZE, tmp_dkek, kdata, key_size) != 0) {
free(kdata);
return SW_EXEC_ERROR();
}
release_dkek();
mbedtls_ecdh_init(&ctx);
mbedtls_ecp_group_id gid = kdata[0];
int r = 0;
r = mbedtls_ecdh_setup(&ctx, gid);
if (r != 0) {
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);
if (r != 0) {
mbedtls_ecdh_free(&ctx);
free(kdata);
return SW_DATA_INVALID();
}
free(kdata);
r = mbedtls_ecdh_read_public(&ctx, apdu.cmd_apdu_data-1, apdu.cmd_apdu_data_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();
}
res_APDU_size = olen+1;
mbedtls_ecdh_free(&ctx);
}
else
return SW_WRONG_P1P2();
return SW_OK();
}